DOE Office of Scientific and Technical Information (OSTI.GOV)
Lekov, Alex; Thompson, Lisa; McKane, Aimee
2009-05-11
This report summarizes the Lawrence Berkeley National Laboratory's research to date in characterizing energy efficiency and open automated demand response opportunities for industrial refrigerated warehouses in California. The report describes refrigerated warehouses characteristics, energy use and demand, and control systems. It also discusses energy efficiency and open automated demand response opportunities and provides analysis results from three demand response studies. In addition, several energy efficiency, load management, and demand response case studies are provided for refrigerated warehouses. This study shows that refrigerated warehouses can be excellent candidates for open automated demand response and that facilities which have implemented energy efficiencymore » measures and have centralized control systems are well-suited to shift or shed electrical loads in response to financial incentives, utility bill savings, and/or opportunities to enhance reliability of service. Control technologies installed for energy efficiency and load management purposes can often be adapted for open automated demand response (OpenADR) at little additional cost. These improved controls may prepare facilities to be more receptive to OpenADR due to both increased confidence in the opportunities for controlling energy cost/use and access to the real-time data.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lekov, Alex; Thompson, Lisa; McKane, Aimee
This report summarizes the Lawrence Berkeley National Laboratory?s research to date in characterizing energy efficiency and automated demand response opportunities for wastewater treatment facilities in California. The report describes the characteristics of wastewater treatment facilities, the nature of the wastewater stream, energy use and demand, as well as details of the wastewater treatment process. It also discusses control systems and energy efficiency and automated demand response opportunities. In addition, several energy efficiency and load management case studies are provided for wastewater treatment facilities.This study shows that wastewater treatment facilities can be excellent candidates for open automated demand response and thatmore » facilities which have implemented energy efficiency measures and have centralized control systems are well-suited to shift or shed electrical loads in response to financial incentives, utility bill savings, and/or opportunities to enhance reliability of service. Control technologies installed for energy efficiency and load management purposes can often be adapted for automated demand response at little additional cost. These improved controls may prepare facilities to be more receptive to open automated demand response due to both increased confidence in the opportunities for controlling energy cost/use and access to the real-time data.« less
Aggregate modeling of fast-acting demand response and control under real-time pricing
Chassin, David P.; Rondeau, Daniel
2016-08-24
This paper develops and assesses the performance of a short-term demand response (DR) model for utility load control with applications to resource planning and control design. Long term response models tend to underestimate short-term demand response when induced by prices. This has two important consequences. First, planning studies tend to undervalue DR and often overlook its benefits in utility demand management program development. Second, when DR is not overlooked, the open-loop DR control gain estimate may be too low. This can result in overuse of load resources, control instability and excessive price volatility. Our objective is therefore to develop amore » more accurate and better performing short-term demand response model. We construct the model from first principles about the nature of thermostatic load control and show that the resulting formulation corresponds exactly to the Random Utility Model employed in economics to study consumer choice. The model is tested against empirical data collected from field demonstration projects and is shown to perform better than alternative models commonly used to forecast demand in normal operating conditions. Finally, the results suggest that (1) existing utility tariffs appear to be inadequate to incentivize demand response, particularly in the presence of high renewables, and (2) existing load control systems run the risk of becoming unstable if utilities close the loop on real-time prices.« less
Aggregate modeling of fast-acting demand response and control under real-time pricing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chassin, David P.; Rondeau, Daniel
This paper develops and assesses the performance of a short-term demand response (DR) model for utility load control with applications to resource planning and control design. Long term response models tend to underestimate short-term demand response when induced by prices. This has two important consequences. First, planning studies tend to undervalue DR and often overlook its benefits in utility demand management program development. Second, when DR is not overlooked, the open-loop DR control gain estimate may be too low. This can result in overuse of load resources, control instability and excessive price volatility. Our objective is therefore to develop amore » more accurate and better performing short-term demand response model. We construct the model from first principles about the nature of thermostatic load control and show that the resulting formulation corresponds exactly to the Random Utility Model employed in economics to study consumer choice. The model is tested against empirical data collected from field demonstration projects and is shown to perform better than alternative models commonly used to forecast demand in normal operating conditions. Finally, the results suggest that (1) existing utility tariffs appear to be inadequate to incentivize demand response, particularly in the presence of high renewables, and (2) existing load control systems run the risk of becoming unstable if utilities close the loop on real-time prices.« less
Aggregate modeling of fast-acting demand response and control under real-time pricing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chassin, David P.; Rondeau, Daniel
This paper develops and assesses the performance of a short-term demand response (DR) model for utility load control with applications to resource planning and control design. Long term response models tend to underestimate short-term demand response when induced by prices. This has two important consequences. First, planning studies tend to undervalue DR and often overlook its benefits in utility demand management program development. Second, when DR is not overlooked, the open-loop DR control gain estimate may be too low. This can result in overuse of load resources, control instability and excessive price volatility. Our objective is therefore to develop amore » more accurate and better performing short-term demand response model. We construct the model from first principles about the nature of thermostatic load control and show that the resulting formulation corresponds exactly to the Random Utility Model employed in economics to study consumer choice. The model is tested against empirical data collected from field demonstration projects and is shown to perform better than alternative models commonly used to forecast demand in normal operating conditions. The results suggest that (1) existing utility tariffs appear to be inadequate to incentivize demand response, particularly in the presence of high renewables, and (2) existing load control systems run the risk of becoming unstable if utilities close the loop on real-time prices.« less
Centralized and Decentralized Control for Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lu, Shuai; Samaan, Nader A.; Diao, Ruisheng
2011-04-29
Demand response has been recognized as an essential element of the smart grid. Frequency response, regulation and contingency reserve functions performed traditionally by generation resources are now starting to involve demand side resources. Additional benefits from demand response include peak reduction and load shifting, which will defer new infrastructure investment and improve generator operation efficiency. Technical approaches designed to realize these functionalities can be categorized into centralized control and decentralized control, depending on where the response decision is made. This paper discusses these two control philosophies and compares their relative advantages and disadvantages in terms of delay time, predictability, complexity,more » and reliability. A distribution system model with detailed household loads and controls is built to demonstrate the characteristics of the two approaches. The conclusion is that the promptness and reliability of decentralized control should be combined with the predictability and simplicity of centralized control to achieve the best performance of the smart grid.« less
Opportunities for Automated Demand Response in California’s Dairy Processing Industry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Homan, Gregory K.; Aghajanzadeh, Arian; McKane, Aimee
During periods of peak electrical demand on the energy grid or when there is a shortage of supply, the stability of the grid may be compromised or the cost of supplying electricity may rise dramatically, respectively. Demand response programs are designed to mitigate the severity of these problems and improve reliability by reducing the demand on the grid during such critical times. In 2010, the Demand Response Research Center convened a group of industry experts to suggest potential industries that would be good demand response program candidates for further review. The dairy industry was suggested due to the perception thatmore » the industry had suitable flexibility and automatic controls in place. The purpose of this report is to provide an initial description of the industry with regard to demand response potential, specifically automated demand response. This report qualitatively describes the potential for participation in demand response and automated demand response by dairy processing facilities in California, as well as barriers to widespread participation. The report first describes the magnitude, timing, location, purpose, and manner of energy use. Typical process equipment and controls are discussed, as well as common impediments to participation in demand response and automated demand response programs. Two case studies of demand response at dairy facilities in California and across the country are reviewed. Finally, recommendations are made for future research that can enhance the understanding of demand response potential in this industry.« less
Pupillary Response to Cognitive Demand in Parkinson’s Disease: A Pilot Study
Kahya, Melike; Moon, Sanghee; Lyons, Kelly E.; Pahwa, Rajesh; Akinwuntan, Abiodun E.; Devos, Hannes
2018-01-01
Previous studies have shown that pupillary response, a physiological measure of cognitive workload, reflects cognitive demand in healthy younger and older adults. However, the relationship between cognitive workload and cognitive demand in Parkinson’s disease (PD) remains unclear. The aim of this pilot study was to examine the pupillary response to cognitive demand in a letter-number sequencing (LNS) task between 16 non-demented individuals with PD (age, median (Q1–Q3): 68 (62–72); 10 males) and 10 control participants (age: 63 (59–67); 2 males), matched for age, education, and Montreal Cognitive Assessment (MOCA) scores. A mixed model analysis was employed to investigate cognitive workload changes as a result of incremental cognitive demand for both groups. As expected, no differences were found in cognitive scores on the LNS between groups. Cognitive workload, exemplified by greater pupil dilation, increased with incremental cognitive demand in both groups (p = 0.003). No significant between-group (p = 0.23) or interaction effects were found (p = 0.45). In addition, individuals who achieved to complete the task at higher letter-number (LN) load responded differently to increased cognitive demand compared with those who completed at lower LN load (p < 0.001), regardless of disease status. Overall, the findings indicated that pupillary response reflects incremental cognitive demand in non-demented people with PD and healthy controls. Further research is needed to investigate the pupillary response to incremental cognitive demand of PD patients with dementia compared to non-demented PD and healthy controls. Highlights -Pupillary response reflects cognitive demand in both non-demented people with PD and healthy controls-Although not significant due to insufficient power, non-demented individuals with PD had increased cognitive workload compared to the healthy controls throughout the testing-Pupillary response may be a valid measure of cognitive demand in non-demented individuals with PD-In future, pupillary response might be used to detect cognitive impairment in individuals with PD PMID:29692720
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Joyce Jihyun; Yin, Rongxin; Kiliccote, Sila
Open Automated Demand Response (OpenADR), an XML-based information exchange model, is used to facilitate continuous price-responsive operation and demand response participation for large commercial buildings in New York who are subject to the default day-ahead hourly pricing. We summarize the existing demand response programs in New York and discuss OpenADR communication, prioritization of demand response signals, and control methods. Building energy simulation models are developed and field tests are conducted to evaluate continuous energy management and demand response capabilities of two commercial buildings in New York City. Preliminary results reveal that providing machine-readable prices to commercial buildings can facilitate bothmore » demand response participation and continuous energy cost savings. Hence, efforts should be made to develop more sophisticated algorithms for building control systems to minimize customer's utility bill based on price and reliability information from the electricity grid.« less
Electric Water Heater Modeling and Control Strategies for Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Diao, Ruisheng; Lu, Shuai; Elizondo, Marcelo A.
2012-07-22
Abstract— Demand response (DR) has a great potential to provide balancing services at normal operating conditions and emergency support when a power system is subject to disturbances. Effective control strategies can significantly relieve the balancing burden of conventional generators and reduce investment on generation and transmission expansion. This paper is aimed at modeling electric water heaters (EWH) in households and tests their response to control strategies to implement DR. The open-loop response of EWH to a centralized signal is studied by adjusting temperature settings to provide regulation services; and two types of decentralized controllers are tested to provide frequency supportmore » following generator trips. EWH models are included in a simulation platform in DIgSILENT to perform electromechanical simulation, which contains 147 households in a distribution feeder. Simulation results show the dependence of EWH response on water heater usage . These results provide insight suggestions on the need of control strategies to achieve better performance for demand response implementation. Index Terms— Centralized control, decentralized control, demand response, electrical water heater, smart grid« less
Opportunities for Automated Demand Response in California Wastewater Treatment Facilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aghajanzadeh, Arian; Wray, Craig; McKane, Aimee
Previous research over a period of six years has identified wastewater treatment facilities as good candidates for demand response (DR), automated demand response (Auto-DR), and Energy Efficiency (EE) measures. This report summarizes that work, including the characteristics of wastewater treatment facilities, the nature of the wastewater stream, energy used and demand, as well as details of the wastewater treatment process. It also discusses control systems and automated demand response opportunities. Furthermore, this report summarizes the DR potential of three wastewater treatment facilities. In particular, Lawrence Berkeley National Laboratory (LBNL) has collected data at these facilities from control systems, submetered processmore » equipment, utility electricity demand records, and governmental weather stations. The collected data were then used to generate a summary of wastewater power demand, factors affecting that demand, and demand response capabilities. These case studies show that facilities that have implemented energy efficiency measures and that have centralized control systems are well suited to shed or shift electrical loads in response to financial incentives, utility bill savings, and/or opportunities to enhance reliability of service. In summary, municipal wastewater treatment energy demand in California is large, and energy-intensive equipment offers significant potential for automated demand response. In particular, large load reductions were achieved by targeting effluent pumps and centrifuges. One of the limiting factors to implementing demand response is the reaction of effluent turbidity to reduced aeration at an earlier stage of the process. Another limiting factor is that cogeneration capabilities of municipal facilities, including existing power purchase agreements and utility receptiveness to purchasing electricity from cogeneration facilities, limit a facility’s potential to participate in other DR activities.« less
Venkatraman, Vinod; Rosati, Alexandra G; Taren, Adrienne A; Huettel, Scott A
2009-10-21
The dorsomedial prefrontal cortex (DMPFC) plays a central role in aspects of cognitive control and decision making. Here, we provide evidence for an anterior-to-posterior topography within the DMPFC using tasks that evoke three distinct forms of control demands--response, decision, and strategic--each of which could be mapped onto independent behavioral data. Specifically, we identify three spatially distinct regions within the DMPFC: a posterior region associated with control demands evoked by multiple incompatible responses, a middle region associated with control demands evoked by the relative desirability of decision options, and an anterior region that predicts control demands related to deviations from an individual's preferred decision-making strategy. These results provide new insight into the functional organization of DMPFC and suggest how recent controversies about its role in complex decision making and response mapping can be reconciled.
Venkatraman, Vinod; Rosati, Alexandra G.; Taren, Adrienne A.; Huettel, Scott A.
2009-01-01
The dorsomedial prefrontal cortex (DMPFC) plays a central role in aspects of cognitive control and decision making. Here, we provide evidence for an anterior-to-posterior topography within the DMPFC using tasks that evoke three distinct forms of control demands – response, decision, and strategic – each of which could be mapped on to independent behavioral data. Specifically, we identify three spatially distinct regions within the DMPFC: a posterior region associated with control demands evoked by multiple incompatible responses, a middle region associated with control demands evoked by the relative desirability of decision options, and an anterior region that predicts control demands related to deviations from an individual's preferred decision-making strategy. These results provide new insight into the functional organization of DMPFC, and suggest how recent controversies about its role in complex decision making and response mapping can be reconciled. PMID:19846703
NASA Astrophysics Data System (ADS)
Cui, Gaoying; Fan, Jie; Qin, Yuchen; Wang, Dong; Chen, Guangyan
2017-05-01
In order to promote the effective use of demand response load side resources, promote the interaction between supply and demand, enhance the level of customer service and achieve the overall utilization of energy, this paper briefly explain the background significance of design demand response information platform and current situation of domestic and foreign development; Analyse the new demand of electricity demand response combined with the application of Internet and big data technology; Design demand response information platform architecture, construct demand responsive system, analyse process of demand response strategy formulate and intelligent execution implement; study application which combined with the big data, Internet and demand response technology; Finally, from information interaction architecture, control architecture and function design perspective design implementation of demand response information platform, illustrate the feasibility of the proposed platform design scheme implemented in a certain extent.
Smart Buildings and Demand Response
NASA Astrophysics Data System (ADS)
Kiliccote, Sila; Piette, Mary Ann; Ghatikar, Girish
2011-11-01
Advances in communications and control technology, the strengthening of the Internet, and the growing appreciation of the urgency to reduce demand side energy use are motivating the development of improvements in both energy efficiency and demand response (DR) systems in buildings. This paper provides a framework linking continuous energy management and continuous communications for automated demand response (Auto-DR) in various times scales. We provide a set of concepts for monitoring and controls linked to standards and procedures such as Open Automation Demand Response Communication Standards (OpenADR). Basic building energy science and control issues in this approach begin with key building components, systems, end-uses and whole building energy performance metrics. The paper presents a framework about when energy is used, levels of services by energy using systems, granularity of control, and speed of telemetry. DR, when defined as a discrete event, requires a different set of building service levels than daily operations. We provide examples of lessons from DR case studies and links to energy efficiency.
Automated Demand Response for Energy Sustainability
2015-05-01
project’s stated performance objectives. Emerging opportunities to participate in wholesale electricity markets can provide important economic, energy, and...Response in Wholesale Electricity Markets ..................................................... 7 Figure 5. Demand Bidding Communication and Control...resource in response to market or reliability conditions Demand Bidding Program DR programs that encourage customers to bid into an electricity market
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piette, Mary Ann
California needs new, responsive, demand-side energy technologies to ensure that periods of tight electricity supply on the grid don't turn into power outages. Led by Berkeley Lab's Mary Ann Piette, the California Energy Commission (through its Public Interest Energy Research Program) has established a Demand Response Research Center that addresses two motivations for adopting demand responsiveness: reducing average electricity prices and preventing future electricity crises. The research seeks to understand factors that influence "what works" in Demand Response. Piette's team is investigating the two types of demand response, load response and price response, that may influence and reduce the usemore » of peak electric power through automated controls, peak pricing, advanced communications, and other strategies.« less
Saving Power at Peak Hours (LBNL Science at the Theater)
Piette, Mary Ann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2018-05-23
California needs new, responsive, demand-side energy technologies to ensure that periods of tight electricity supply on the grid don't turn into power outages. Led by Berkeley Lab's Mary Ann Piette, the California Energy Commission (through its Public Interest Energy Research Program) has established a Demand Response Research Center that addresses two motivations for adopting demand responsiveness: reducing average electricity prices and preventing future electricity crises. The research seeks to understand factors that influence "what works" in Demand Response. Piette's team is investigating the two types of demand response, load response and price response, that may influence and reduce the use of peak electric power through automated controls, peak pricing, advanced communications, and other strategies.
Fedota, John R; Matous, Allison L; Salmeron, Betty Jo; Gu, Hong; Ross, Thomas J; Stein, Elliot A
2016-09-01
Deficits in cognitive control processes are a primary characteristic of nicotine addiction. However, while network-based connectivity measures of dysfunction have frequently been observed, empirical evidence of task-based dysfunction in these processes has been inconsistent. Here, in a sample of smokers (n=35) and non-smokers (n=21), a previously validated parametric flanker task is employed to characterize addiction-related alterations in responses to varying (ie, high, intermediate, and low) demands for cognitive control. This approach yields a demand-response curve that aims to characterize potential non-linear responses to increased demand for control, including insensitivities or lags in fully activating the cognitive control network. We further used task-based differences in activation between groups as seeds for resting-state analysis of network dysfunction in an effort to more closely link prior inconsistencies in task-related activation with evidence of impaired network connectivity in smokers. For both smokers and non-smokers, neuroimaging results showed similar increases in activation in brain areas associated with cognitive control. However, reduced activation in right insula was seen only in smokers and only when processing intermediate demand for cognitive control. Further, in smokers, this task-modulated right insula showed weaker functional connectivity with the superior frontal gyrus, a component of the task-positive executive control network. These results demonstrate that the neural instantiation of salience attribution in smokers is both more effortful to fully activate and has more difficulty communicating with the exogenous, task-positive, executive control network. Together, these findings further articulate the cognitive control dysfunction associated with smoking and illustrate a specific brain circuit potentially responsible.
Effects of Demand Response on Retail and Wholesale Power Markets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chassin, David P.; Kalsi, Karanjit
2012-07-26
Demand response has grown to be a part of the repertoire of resources used by utilities to manage the balance between generation and load. In recent years, advances in communications and control technology have enabled utilities to consider continuously controlling demand response to meet generation, rather than the other way around. This paper discusses the economic applications of a general method for load resource analysis that parallels the approach used to analyze generation resources and uses the method to examine the results of the US Department of Energy’s Olympic Peninsula Demonstration Testbed. A market-based closed-loop system of controllable assets ismore » discussed with necessary and sufficient conditions on system controllability, observability and stability derived.« less
End-User Tools Towards AN Efficient Electricity Consumption: the Dynamic Smart Grid
NASA Astrophysics Data System (ADS)
Kamel, Fouad; Kist, Alexander A.
2010-06-01
Growing uncontrolled electrical demands have caused increased supply requirements. This causes volatile electrical markets and has detrimental unsustainable environmental impacts. The market is presently characterized by regular daily peak demand conditions associated with high electricity prices. A demand-side response system can limit peak demands to an acceptable level. The proposed scheme is based on energy demand and price information which is available online. An online server is used to communicate the information of electricity suppliers to users, who are able to use the information to manage and control their own demand. A configurable, intelligent switching system is used to control local loads during peak events and mange the loads at other times as necessary. The aim is to shift end user loads towards periods where energy demand and therefore also prices are at the lowest. As a result, this will flatten the load profile and avoiding load peeks which are costly for suppliers. The scheme is an endeavour towards achieving a dynamic smart grid demand-side-response environment using information-based communication and computer-controlled switching. Diffusing the scheme shall lead to improved electrical supply services and controlled energy consumption and prices.
Key Residential Building Equipment Technologies for Control and Grid Support PART I (Residential)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Starke, Michael R; Onar, Omer C; DeVault, Robert C
2011-09-01
Electrical energy consumption of the residential sector is a crucial area of research that has in the past primarily focused on increasing the efficiency of household devices such as water heaters, dishwashers, air conditioners, and clothes washer and dryer units. However, the focus of this research is shifting as objectives such as developing the smart grid and ensuring that the power system remains reliable come to the fore, along with the increasing need to reduce energy use and costs. Load research has started to focus on mechanisms to support the power system through demand reduction and/or reliability services. The powermore » system relies on matching generation and load, and day-ahead and real-time energy markets capture most of this need. However, a separate set of grid services exist to address the discrepancies in load and generation arising from contingencies and operational mismatches, and to ensure that the transmission system is available for delivery of power from generation to load. Currently, these grid services are mostly provided by generation resources. The addition of renewable resources with their inherent variability can complicate the issue of power system reliability and lead to the increased need for grid services. Using load as a resource, through demand response programs, can fill the additional need for flexible resources and even reduce costly energy peaks. Loads have been shown to have response that is equal to or better than generation in some cases. Furthermore, price-incentivized demand response programs have been shown to reduce the peak energy requirements, thereby affecting the wholesale market efficiency and overall energy prices. The residential sector is not only the largest consumer of electrical energy in the United States, but also has the highest potential to provide demand reduction and power system support, as technological advancements in load control, sensor technologies, and communication are made. The prevailing loads based on the largest electrical energy consumers in the residential sector are space heating and cooling, washer and dryer, water heating, lighting, computers and electronics, dishwasher and range, and refrigeration. As the largest loads, these loads provide the highest potential for delivering demand response and reliability services. Many residential loads have inherent flexibility that is related to the purpose of the load. Depending on the load type, electric power consumption levels can either be ramped, changed in a step-change fashion, or completely removed. Loads with only on-off capability (such as clothes washers and dryers) provide less flexibility than resources that can be ramped or step-changed. Add-on devices may be able to provide extra demand response capabilities. Still, operating residential loads effectively requires awareness of the delicate balance of occupants health and comfort and electrical energy consumption. This report is Phase I of a series of reports aimed at identifying gaps in automated home energy management systems for incorporation of building appliances, vehicles, and renewable adoption into a smart grid, specifically with the intent of examining demand response and load factor control for power system support. The objective is to capture existing gaps in load control, energy management systems, and sensor technology with consideration of PHEV and renewable technologies to establish areas of research for the Department of Energy. In this report, (1) data is collected and examined from state of the art homes to characterize the primary residential loads as well as PHEVs and photovoltaic for potential adoption into energy management control strategies; and (2) demand response rules and requirements across the various demand response programs are examined for potential participation of residential loads. This report will be followed by a Phase II report aimed at identifying the current state of technology of energy management systems, sensors, and communication technologies for demand response and load factor control applications for the residential sector. The purpose is to cover the gaps that exist in the information captured by the sensors for energy management system to be able to provide demand response and load factor control. The vision is the development of an energy management system or other controlling enterprise hardware and software that is not only able to control loads, PHEVs, and renewable generation for demand response and load factor control, but also to do so with consumer comforts in mind and in an optimal fashion.« less
APPARATUS FOR CONTROL OF A BOILING REACTOR RESPONSIVE TO STEAM DEMAND
Treshow, M.
1963-07-23
A method of controlling a fuel-rod-in-tube-type boilingwater reactor having nozzles at the point of water entry into the tube is described. Water is pumped into the nozzles by an auxiliary pump operated by steam from an interstage position of the associated turbine, so that the pumping speed is responsive to turbine demand. (AEC)
Effects of Working Memory Demand on Neural Mechanisms of Motor Response Selection and Control
Barber, Anita D.; Caffo, Brian S.; Pekar, James J.; Mostofsky, Stewart H.
2013-01-01
Inhibitory control commonly recruits a number of frontal regions: pre-supplementary motor area (pre-SMA), frontal eye fields (FEFs), and right-lateralized posterior inferior frontal gyrus (IFG), dorsal anterior insula (DAI), dorsolateral prefrontal cortex (DLPFC), and inferior frontal junction (IFJ). These regions may directly implement inhibitory motor control or may be more generally involved in executive control functions. Two go/no-go tasks were used to distinguish regions specifically recruited for inhibition from those that additionally show increased activity with working memory demand. The pre-SMA and IFG were recruited for inhibition in both tasks and did not have greater activation for working memory demand on no-go trials, consistent with a role in inhibitory control. Activation in pre-SMA also responded to response selection demand and was increased with working memory on go trials specifically. The bilateral FEF and right DAI were commonly active for no-go trials. The FEF was also recruited to a greater degree with working memory demand on go trials and may bias top–down information when stimulus–response mappings change. The DAI, additionally responded to increased working memory demand on both go and no-go trials and may be involved in accessing sustained task information, alerting, or autonomic changes when cognitive demands increase. DLPFC activation was consistent with a role in working memory retrieval on both go and no-go trials. The inferior frontal junction, on the other hand, had greater activation with working memory specifically for no-go trials and may detect salient stimuli when the task requires frequent updating of working memory representations. PMID:23530923
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Joyce Jihyun; Schetrit, Oren; Yin, Rongxin
Demand response (DR) – allowing customers to respond to reliability requests and market prices by changing electricity use from their normal consumption pattern – continues to be seen as an attractive means of demand-side management and a fundamental smart-grid improvement that links supply and demand. From October 2011 to December 2013, the Demand Response Research Center at Lawrence Berkeley National Laboratory, the New York State Energy Research and Development Authority, and partners Honeywell and Akuacom, have conducted a demonstration project enabling Automated Demand Response (Auto-DR) in large commercial buildings located in New York City using Open Automated Demand Response (OpenADR)more » communication protocols. In particular, this project focuses on demonstrating how the OpenADR platform, enabled by Akuacom, can automate and simplify interactions between buildings and various stakeholders in New York State and enable the automation of customers’ price response to yield bill savings under dynamic pricing. In this paper, the cost control opportunities under day-ahead hourly pricing and Auto-DR control strategies are presented for four demonstration buildings; present the breakdown of Auto-DR enablement costs; summarize the field test results and their load impact; and show potential bill savings by enabling automated price response under Consolidated Edison’s Mandatory Hourly Pricing (MHP) tariff. For one of the sites, the potential bill savings at the site’s current retail rate are shown. Facility managers were given granular equipment-level opt-out capability to ensure full control of the sites during the Auto-DR implementation. The expected bill savings ranged from 1.1% to 8.0% of the total MHP bill. The automation and enablement costs ranged from $70 to $725 per kW shed. The results show that OpenADR can facilitate the automation of price response, deliver savings to the customers and opt-out capability of the implementation retains control of the sites by facility managers.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Di; Lian, Jianming; Sun, Yannan
Demand response is representing a significant but largely untapped resource that can greatly enhance the flexibility and reliability of power systems. In this paper, a hierarchical control framework is proposed to facilitate the integrated coordination between distributed energy resources and demand response. The proposed framework consists of coordination and device layers. In the coordination layer, various resource aggregations are optimally coordinated in a distributed manner to achieve the system-level objectives. In the device layer, individual resources are controlled in real time to follow the optimal power generation or consumption dispatched from the coordination layer. For the purpose of practical applications,more » a method is presented to determine the utility functions of controllable loads by taking into account the real-time load dynamics and the preferences of individual customers. The effectiveness of the proposed framework is validated by detailed simulation studies.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broeer, Torsten; Fuller, Jason C.; Tuffner, Francis K.
2014-01-31
Electricity generation from wind power and other renewable energy sources is increasing, and their variability introduces new challenges to the power system. The emergence of smart grid technologies in recent years has seen a paradigm shift in redefining the electrical system of the future, in which controlled response of the demand side is used to balance fluctuations and intermittencies from the generation side. This paper presents a modeling framework for an integrated electricity system where loads become an additional resource. The agent-based model represents a smart grid power system integrating generators, transmission, distribution, loads and market. The model incorporates generatormore » and load controllers, allowing suppliers and demanders to bid into a Real-Time Pricing (RTP) electricity market. The modeling framework is applied to represent a physical demonstration project conducted on the Olympic Peninsula, Washington, USA, and validation simulations are performed using actual dynamic data. Wind power is then introduced into the power generation mix illustrating the potential of demand response to mitigate the impact of wind power variability, primarily through thermostatically controlled loads. The results also indicate that effective implementation of Demand Response (DR) to assist integration of variable renewable energy resources requires a diversity of loads to ensure functionality of the overall system.« less
Teuchmann, K; Totterdell, P; Parker, S K
1999-01-01
Experience sampling methodology was used to examine how work demands translate into acute changes in affective response and thence into chronic response. Seven accountants reported their reactions 3 times a day for 4 weeks on pocket computers. Aggregated analysis showed that mood and emotional exhaustion fluctuated in parallel with time pressure over time. Disaggregated time-series analysis confirmed the direct impact of high-demand periods on the perception of control, time pressure, and mood and the indirect impact on emotional exhaustion. A curvilinear relationship between time pressure and emotional exhaustion was shown. The relationships between work demands and emotional exhaustion changed between high-demand periods and normal working periods. The results suggest that enhancing perceived control may alleviate the negative effects of time pressure.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-30
... to Demands in Legal Proceedings Among Private Litigants AGENCY: Office of the General Counsel, HUD... forms of information technology, e.g., permitting electronic submission of responses. This Notice also... Response to Demands in Legal Proceedings Among Private Litigants. OMB Control Number, if applicable: 2501...
Schaubroeck, J; Lam, S S; Xie, J L
2000-08-01
This study examined how cultural differences and efficacy perceptions influence the role of job control in coping with job demands. Perceiving higher control mitigated the effects of demands on psychological health symptoms and turnover intentions only among American bank tellers reporting high job self-efficacy. Among American tellers reporting low job self-efficacy, perceived control exacerbated the effects of demands. However, in a matched Hong Kong sample, collective efficacy interacted in the same way with control and demands as job self-efficacy had in the American sample. These differences appear to be explained by the individual attributes of idiocentrism and allocentrism that are linked to the societal norms of individualism and collectivism, respectively.
Schechter, J; Green, L W; Olsen, L; Kruse, K; Cargo, M
1997-01-01
To apply Karasek's Job Content Model to an analysis of the relationships between job type and perceived stress and stress behaviors in a large company during a period of reorganization and downsizing. Cross-sectional mail-out, mail-back survey. A large Canadian telephone/telecommunications company. Stratified random sample (stratified by job category) of 2200 out of 13,000 employees with a response rate of 48.8%. Responses to 25 of Karasek's core questions were utilized to define four job types: low-demand and high control = "relaxed"; high demand and high control = "active"; low demand and low control = "passive", and high demand and low control = "high strain." These job types were compared against self-reported stress levels, perceived general level of health, absenteeism, alcohol use, exercise level, and use of medications and drugs. Similar analyses were performed to assess the influence of shift work. Employees with "passive" or "high strain" job types reported higher levels of stress (trend test p < .0001); poorer health (trend test P = .006); and higher levels of absenteeism (trend test p < .0001). More shift workers reported themselves in poor or fair health (chi-square p = .018) and reported high levels of stress at home (chi-square p = .002) than nonshift workers. The relationships between job type and levels of stress, health and absenteeism, however, held for nonshift workers as well. Job types with high demand and low control were associated with increased stress, increased absenteeism, and poorer self-concept of health. The demand/control model of Karasek and Theorell was validated in this setting with respect to stress and some stress-associated attitudes and behaviors.
de Croon, E M; Blonk, R; de Zwart, B C H; Frings-Dresen, M; Broersen, J
2002-01-01
Objectives: Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers. Methods: From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. Results: The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. Conclusions: Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work. PMID:12040108
de Croon, E M; Blonk, R W B; de Zwart, B C H; Frings-Dresen, M H W; Broersen, J P J
2002-06-01
Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers. From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work.
Transactive Control of Commercial Buildings for Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hao, He; Corbin, Charles D.; Kalsi, Karanjit
Transactive control is a type of distributed control strategy that uses market mechanism to engage self-interested responsive loads to achieve power balance in the electrical power grid. In this paper, we propose a transactive control approach of commercial building Heating, Ventilation, and Air- Conditioning (HVAC) systems for demand response. We first describe the system models, and identify their model parameters using data collected from Systems Engineering Building (SEB) located on our Pacific Northwest National Laboratory (PNNL) campus. We next present a transactive control market structure for commercial building HVAC system, and describe its agent bidding and market clearing strategies. Severalmore » case studies are performed in a simulation environment using Building Control Virtual Test Bed (BCVTB) and calibrated SEB EnergyPlus model. We show that the proposed transactive control approach is very effective at peak clipping, load shifting, and strategic conservation for commercial building HVAC systems.« less
Context-specific adjustment of cognitive control: Transfer of adaptive control sets.
Surrey, Caroline; Dreisbach, Gesine; Fischer, Rico
2017-11-01
Cognitive control protects processing of relevant information from interference by irrelevant information. The level of this processing selectivity can be flexibly adjusted to different control demands (e.g., frequency of conflict) associated with a certain context, leading to the formation of specific context-control associations. In the present study we investigated the robustness and transferability of the acquired context-control demands to new situations. In three experiments, we used a version of the context-specific proportion congruence (CSPC) paradigm, in which each context (e.g., location) is associated with a specific conflict frequency, determining high and low control demands. In a learning phase, associations between context and control demands were established. In a subsequent transfer block, stimulus-response mappings, whole task sets, or context-control demands changed. Results showed an impressive robustness of context-control associations, as context-specific adjustments of control from the learning phase were virtually unaffected by new stimuli and tasks in the transfer block. Only a change of the context-control demand eliminated the context-specific adjustment of control. These findings suggest that context-control associations that have proven to be adaptive in the past are continuously applied despite major changes in the task structure as long as the context-control associations remain the same.
Gaschler, Robert; Marewski, Julian N.; Wenke, Dorit; Frensch, Peter A.
2014-01-01
After incidentally learning about a hidden regularity, participants can either continue to solve the task as instructed or, alternatively, apply a shortcut. Past research suggests that the amount of conflict implied by adopting a shortcut seems to bias the decision for vs. against continuing instruction-coherent task processing. We explored whether this decision might transfer from one incidental learning task to the next. Theories that conceptualize strategy change in incidental learning as a learning-plus-decision phenomenon suggest that high demands to adhere to instruction-coherent task processing in Task 1 will impede shortcut usage in Task 2, whereas low control demands will foster it. We sequentially applied two established incidental learning tasks differing in stimuli, responses and hidden regularity (the alphabet verification task followed by the serial reaction task, SRT). While some participants experienced a complete redundancy in the task material of the alphabet verification task (low demands to adhere to instructions), for others the redundancy was only partial. Thus, shortcut application would have led to errors (high demands to follow instructions). The low control demand condition showed the strongest usage of the fixed and repeating sequence of responses in the SRT. The transfer results are in line with the learning-plus-decision view of strategy change in incidental learning, rather than with resource theories of self-control. PMID:25506336
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schetrit, Oren; Kim, Joyce; Yin, Rongxin
2014-08-01
Automated demand response (Auto-DR) is expected to close the loop between buildings and the grid by providing machine-to-machine communications to curtail loads without the need for human intervention. Hence, it can offer more reliable and repeatable demand response results to the grid than the manual approach and make demand response participation a hassle-free experience for customers. However, many building operators misunderstand Auto-DR and are afraid of losing control over their building operation. To ease the transition from manual to Auto-DR, we designed and implemented granular control of Auto-DR systems so that building operators could modify or opt out of individualmore » load-shed strategies whenever they wanted. This paper reports the research findings from this effort demonstrated through a field study in large commercial buildings located in New York City. We focused on (1) understanding how providing granular control affects building operators’ perspective on Auto-DR, and (2) evaluating the usefulness of granular control by examining their interaction with the Auto-DR user interface during test events. Through trend log analysis, interviews, and surveys, we found that: (1) the opt-out capability during Auto-DR events can remove the feeling of being forced into load curtailments and increase their willingness to adopt Auto-DR; (2) being able to modify individual load-shed strategies allows flexible Auto-DR participation that meets the building’s changing operational requirements; (3) a clear display of automation strategies helps building operators easily identify how Auto-DR is functioning and can build trust in Auto-DR systems.« less
Effect of Cognitive Demand on Functional Visual Field Performance in Senior Drivers with Glaucoma
Gangeddula, Viswa; Ranchet, Maud; Akinwuntan, Abiodun E.; Bollinger, Kathryn; Devos, Hannes
2017-01-01
Purpose: To investigate the effect of cognitive demand on functional visual field performance in drivers with glaucoma. Method: This study included 20 drivers with open-angle glaucoma and 13 age- and sex-matched controls. Visual field performance was evaluated under different degrees of cognitive demand: a static visual field condition (C1), dynamic visual field condition (C2), and dynamic visual field condition with active driving (C3) using an interactive, desktop driving simulator. The number of correct responses (accuracy) and response times on the visual field task were compared between groups and between conditions using Kruskal–Wallis tests. General linear models were employed to compare cognitive workload, recorded in real-time through pupillometry, between groups and conditions. Results: Adding cognitive demand (C2 and C3) to the static visual field test (C1) adversely affected accuracy and response times, in both groups (p < 0.05). However, drivers with glaucoma performed worse than did control drivers when the static condition changed to a dynamic condition [C2 vs. C1 accuracy; glaucoma: median difference (Q1–Q3) 3 (2–6.50) vs. controls: 2 (0.50–2.50); p = 0.05] and to a dynamic condition with active driving [C3 vs. C1 accuracy; glaucoma: 2 (2–6) vs. controls: 1 (0.50–2); p = 0.02]. Overall, drivers with glaucoma exhibited greater cognitive workload than controls (p = 0.02). Conclusion: Cognitive demand disproportionately affects functional visual field performance in drivers with glaucoma. Our results may inform the development of a performance-based visual field test for drivers with glaucoma. PMID:28912712
Feeding styles and child weight status among recent immigrant mother-child dyads.
Tovar, Alison; Hennessy, Erin; Pirie, Alex; Must, Aviva; Gute, David M; Hyatt, Raymond R; Kamins, Christina Luongo; Hughes, Sheryl O; Boulos, Rebecca; Sliwa, Sarah; Galvão, Heloisa; Economos, Christina D
2012-05-29
Research has shown that parental feeding styles may influence children's food consumption, energy intake, and ultimately, weight status. We examine this relationship, among recent immigrants to the US. Given that immigrant parents and children are at greater risk for becoming overweight/obese with increased time in the US, identification of risk factors for weight gain is critical. Baseline data was collected on 383 mother-child dyads enrolled in Live Well, a community-based, participatory, randomized controlled lifestyle intervention to prevent weight gain in recent immigrant mothers. Socio-demographic information together with heights and weights were collected for both mother and child. Acculturation, behavioral data, and responses to the Caregiver's Feeding Styles Questionnaire (CFSQ) were also obtained from the mother. The children's average age was 6.2 ± 2.7 years, 58% male. Mothers had been in the country for an average of 6.0 ± 3.3 years, and are Brazilian (36%), Haitian (34%) and Latino (30%). Seventy-two percent of the mothers were overweight/obese, while 43% of the children were overweight/obese. Fifteen percent of mothers reported their feeding style as being high demanding/high responsive; 32% as being high demanding/low responsive; 34% as being low demanding/high responsive and 18% as being low demanding/low responsive. In bivariate analyses, feeding styles significantly differed by child BMIz-score, ethnic group, and mother's perceived stress. In multiple linear regression, a low demanding/high responsive feeding style was found to be positively associated (ß = 0.56) with a higher child weight as compared to high demanding/high responsive, controlling for known covariates (p = 0.01). Most mothers report having a low demanding/high responsive feeding style, which is associated with higher child weight status in this diverse immigrant population. This finding adds to the growing literature that suggests this type of feeding style may be a risk factor for childhood obesity. Further research is needed to help understand the larger socio-cultural context and its influence on feeding dynamics among immigrant families and families of lower incomes. How parents establish a certain feeding style in their home country compared to when they move to the US "obesogenic" environment, should also be explored.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marks, Gary; Wilcox, Edmund; Olsen, Daniel
California agricultural irrigation consumes more than ten billion kilowatt hours of electricity annually and has significant potential for contributing to a reduction of stress on the grid through demand response, permanent load shifting, and energy efficiency measures. To understand this potential, a scoping study was initiated for the purpose of determining the associated opportunities, potential, and adoption challenges in California agricultural irrigation. The primary research for this study was conducted in two ways. First, data was gathered and parsed from published sources that shed light on where the best opportunities for load shifting and demand response lie within the agriculturalmore » irrigation sector. Secondly, a small limited survey was conducted as informal face-to-face interviews with several different California growers to get an idea of their ability and willingness to participate in permanent load shifting and/or demand response programs. Analysis of the data obtained from published sources and the survey reveal demand response and permanent load shifting opportunities by growing region, irrigation source, irrigation method, grower size, and utility coverage. The study examines some solutions for demand response and permanent load shifting in agricultural irrigation, which include adequate irrigation system capacity, automatic controls, variable frequency drives, and the contribution from energy efficiency measures. The study further examines the potential and challenges for grower acceptance of demand response and permanent load shifting in California agricultural irrigation. As part of the examination, the study considers to what extent permanent load shifting, which is already somewhat accepted within the agricultural sector, mitigates the need or benefit of demand response for agricultural irrigation. Recommendations for further study include studies on how to gain grower acceptance of demand response as well as other related studies such as conducting a more comprehensive survey of California growers.« less
Wheaton, Michael G; Fitzgerald, Daniel A; Phan, K Luan; Klumpp, Heide
2014-09-01
Generalized social anxiety disorder (gSAD) is associated with impoverished anterior cingulate cortex (ACC) engagement during attentional control. Attentional Control Theory proposes such deficiencies may be offset when demands on resources are increased to execute goals. To test the hypothesis attentional demands affect ACC response 23 patients with gSAD and 24 matched controls performed an fMRI task involving a target letter in a string of identical targets (low load) or a target letter in a mixed letter string (high load) superimposed on fearful, angry, and neutral face distractors. Regardless of load condition, groups were similar in accuracy and reaction time. Under low load gSAD patients showed deficient rostral ACC recruitment to fearful (vs. neutral) distractors. For high load, increased activation to fearful (vs. neutral) distractors was observed in gSAD suggesting a compensatory function. Results remained after controlling for group differences in depression level. Findings indicate perceptual demand modulates ACC in gSAD. Copyright © 2014 Elsevier B.V. All rights reserved.
Ventral Fronto-Temporal Pathway Supporting Cognitive Control of Episodic Memory Retrieval
Barredo, Jennifer; Öztekin, Ilke; Badre, David
2015-01-01
Achieving our goals often requires guiding access to relevant information from memory. Such goal-directed retrieval requires interactions between systems supporting cognitive control, including ventrolateral prefrontal cortex (VLPFC), and those supporting declarative memory, such as the medial temporal lobes (MTL). However, the pathways by which VLPFC interacts with MTL during retrieval are underspecified. Prior neuroanatomical evidence suggests that a polysynaptic ventral fronto-temporal pathway may support VLPFC–MTL interactions. To test this hypothesis, human participants were scanned using fMRI during performance of a source-monitoring task. The strength of source information was varied via repetition during encoding. Single encoding events should produce a weaker memory trace, thus recovering source information about these items should demand greater cognitive control. Results demonstrated that cortical targets along the ventral path—anterior VLPFC, temporal pole, anterior parahippocampus, and hippocampus—exhibited increases in univariate BOLD response correlated with increases in controlled retrieval demand, independent of factors related to response selection. Further, a functional connectivity analysis indicated that these regions functionally couple and are distinguishable from a dorsal pathway related to response selection demands. These data support a ventral retrieval pathway linking PFC and MTL. PMID:24177990
Demand Response Advanced Controls Framework and Assessment of Enabling Technology Costs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Potter, Jennifer; Cappers, Peter
The Demand Response Advanced Controls Framework and Assessment of Enabling Technology Costs research describe a variety of DR opportunities and the various bulk power system services they can provide. The bulk power system services are mapped to a generalized taxonomy of DR “service types”, which allows us to discuss DR opportunities and bulk power system services in fewer yet broader categories that share similar technological requirements which mainly drive DR enablement costs. The research presents a framework for the costs to automate DR and provides descriptions of the various elements that drive enablement costs. The report introduces the various DRmore » enabling technologies and end-uses, identifies the various services that each can provide to the grid and provides the cost assessment for each enabling technology. In addition to a report, this research includes a Demand Response Advanced Controls Database and User Manual. They are intended to provide users with the data that underlies this research and instructions for how to use that database more effectively and efficiently.« less
A Hybrid Demand Response Simulator Version 1.0
DOE Office of Scientific and Technical Information (OSTI.GOV)
2012-05-02
A hybrid demand response simulator is developed to test different control algorithms for centralized and distributed demand response (DR) programs in a small distribution power grid. The HDRS is designed to model a wide variety of DR services such as peak having, load shifting, arbitrage, spinning reserves, load following, regulation, emergency load shedding, etc. The HDRS does not model the dynamic behaviors of the loads, rather, it simulates the load scheduling and dispatch process. The load models include TCAs (water heaters, air conditioners, refrigerators, freezers, etc) and non-TCAs (lighting, washer, dishwasher, etc.) The ambient temperature changes, thermal resistance, capacitance, andmore » the unit control logics can be modeled for TCA loads. The use patterns of the non-TCA can be modeled by probability of use and probabilistic durations. Some of the communication network characteristics, such as delays and errors, can also be modeled. Most importantly, because the simulator is modular and greatly simplified the thermal models for TCA loads, it is very easy and fast to be used to test and validate different control algorithms in a simulated environment.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Behboodi, Sahand; Chassin, David P.; Djilali, Ned
Coordinated operation of distributed thermostatic loads such as heat pumps and air conditioners can reduce energy costs and prevents grid congestion, while maintaining room temperatures in the comfort range set by consumers. This paper furthers efforts towards enabling thermostatically controlled loads (TCLs) to participate in real-time retail electricity markets under a transactive control paradigm. An agent-based approach is used to develop an effective and low complexity demand response control scheme for TCLs. The proposed scheme adjusts aggregated thermostatic loads according to real-time grid conditions under both heating and cooling modes. Here, a case study is presented showing the method reducesmore » consumer electricity costs by over 10% compared to uncoordinated operation.« less
Behboodi, Sahand; Chassin, David P.; Djilali, Ned; ...
2017-07-29
Coordinated operation of distributed thermostatic loads such as heat pumps and air conditioners can reduce energy costs and prevents grid congestion, while maintaining room temperatures in the comfort range set by consumers. This paper furthers efforts towards enabling thermostatically controlled loads (TCLs) to participate in real-time retail electricity markets under a transactive control paradigm. An agent-based approach is used to develop an effective and low complexity demand response control scheme for TCLs. The proposed scheme adjusts aggregated thermostatic loads according to real-time grid conditions under both heating and cooling modes. Here, a case study is presented showing the method reducesmore » consumer electricity costs by over 10% compared to uncoordinated operation.« less
Stein, Jeffrey S; Tegge, Allison N; Turner, Jamie K; Bickel, Warren K
2018-04-01
Episodic future thinking (EFT), an intervention involving mental simulation of future events, has been shown to reduce both delay discounting and cigarette self-administration. In the present study, we extended these findings by showing that EFT in a web-based sample of smokers reduces delay discounting and intensity of demand for cigarettes (ad libitum consumption) in a hypothetical purchase task. No effect was observed on elasticity of demand (sensitivity to price) or cigarette craving. We also explored whether demand characteristics (specifically, the "good-subject" effect) might be responsible for observed effects. EFT participants were significantly better able than control participants to discern the experimental hypothesis. However, EFT participants were not better than controls at identifying whether they had been assigned to the experimental group and, likewise, showed no differences in attitudes about the experiment and experimenter. Importantly, effects of EFT on delay discounting and demand remained significant even when controlling for measures of demand characteristics, indicating that EFT's effects are independent of participants' perceptions about the experiment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piette, Mary Ann; Sezgen, Osman; Watson, David S.
This report describes the results of a research project to develop and evaluate the performance of new Automated Demand Response (Auto-DR) hardware and software technology in large facilities. Demand Response (DR) is a set of activities to reduce or shift electricity use to improve electric grid reliability, manage electricity costs, and ensure that customers receive signals that encourage load reduction during times when the electric grid is near its capacity. The two main drivers for widespread demand responsiveness are the prevention of future electricity crises and the reduction of electricity prices. Additional goals for price responsiveness include equity through costmore » of service pricing, and customer control of electricity usage and bills. The technology developed and evaluated in this report could be used to support numerous forms of DR programs and tariffs. For the purpose of this report, we have defined three levels of Demand Response automation. Manual Demand Response involves manually turning off lights or equipment; this can be a labor-intensive approach. Semi-Automated Response involves the use of building energy management control systems for load shedding, where a preprogrammed load shedding strategy is initiated by facilities staff. Fully-Automated Demand Response is initiated at a building or facility through receipt of an external communications signal--facility staff set up a pre-programmed load shedding strategy which is automatically initiated by the system without the need for human intervention. We have defined this approach to be Auto-DR. An important concept in Auto-DR is that a facility manager is able to ''opt out'' or ''override'' an individual DR event if it occurs at a time when the reduction in end-use services is not desirable. This project sought to improve the feasibility and nature of Auto-DR strategies in large facilities. The research focused on technology development, testing, characterization, and evaluation relating to Auto-DR. This evaluation also included the related decisionmaking perspectives of the facility owners and managers. Another goal of this project was to develop and test a real-time signal for automated demand response that provided a common communication infrastructure for diverse facilities. The six facilities recruited for this project were selected from the facilities that received CEC funds for new DR technology during California's 2000-2001 electricity crises (AB970 and SB-5X).« less
Tablet based distributed intelligent load management
Lu, Yan; Zhou, Siyuan
2018-01-09
A facility is connected to an electricity utility and is responsive to Demand Response Events. A plurality of devices is each individually connected to the electricity grid via an addressable switch connected to a secure network that is enabled to be individually switched off by a server. An occupant of a room in control of the plurality of devices provides via a Human Machine Interface on a tablet a preferred order of switching off the plurality of devices in case of a Demand Response Event. A configuration file based at least partially on the preferred order and on a severity of the Demand Response Events determines which devices which of the plurality devices will be switched off. The server accesses the configuration file and switches off the devices included in the configuration file.
Systems and methods for energy cost optimization in a building system
Turney, Robert D.; Wenzel, Michael J.
2016-09-06
Methods and systems to minimize energy cost in response to time-varying energy prices are presented for a variety of different pricing scenarios. A cascaded model predictive control system is disclosed comprising an inner controller and an outer controller. The inner controller controls power use using a derivative of a temperature setpoint and the outer controller controls temperature via a power setpoint or power deferral. An optimization procedure is used to minimize a cost function within a time horizon subject to temperature constraints, equality constraints, and demand charge constraints. Equality constraints are formulated using system model information and system state information whereas demand charge constraints are formulated using system state information and pricing information. A masking procedure is used to invalidate demand charge constraints for inactive pricing periods including peak, partial-peak, off-peak, critical-peak, and real-time.
Identifying Demand Responses to Illegal Drug Supply Interdictions.
Cunningham, Scott; Finlay, Keith
2016-10-01
Successful supply-side interdictions into illegal drug markets are predicated on the responsiveness of drug prices to enforcement and the price elasticity of demand for addictive drugs. We present causal estimates that targeted interventions aimed at methamphetamine input markets ('precursor control') can temporarily increase retail street prices, but methamphetamine consumption is weakly responsive to higher drug prices. After the supply interventions, purity-adjusted prices increased then quickly returned to pre-treatment levels within 6-12 months, demonstrating the short-term effects of precursor control. The price elasticity of methamphetamine demand is -0.13 to -0.21 for self-admitted drug treatment admissions and between -0.24 and -0.28 for hospital inpatient admissions. We find some evidence of a positive cross-price effect for cocaine, but we do not find robust evidence that increases in methamphetamine prices increased heroin, alcohol, or marijuana drug use. This study can inform policy discussions regarding other synthesized drugs, including illicit use of pharmaceuticals. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
California DREAMing: The design of residential demand responsive technology with people in mind
NASA Astrophysics Data System (ADS)
Peffer, Therese Evelyn
Electrical utilities worldwide are exploring "demand response" programs to reduce electricity consumption during peak periods. Californian electrical utilities would like to pass the higher cost of peak demand to customers to offset costs, increase reliability, and reduce peak consumption. Variable pricing strategies require technology to communicate a dynamic price to customers and respond to that price. However, evidence from thermostat and energy display studies as well as research regarding energy-saving behaviors suggests that devices cannot effect residential demand response without the sanction and participation of people. This study developed several technologies to promote or enable residential demand response. First, along with a team of students and professors, I designed and tested the Demand Response Electrical Appliance Manager (DREAM). This wireless network of sensors, actuators, and controller with a user interface provides information to intelligently control a residential heating and cooling system and to inform people of their energy usage. We tested the system with computer simulation and in the laboratory and field. Secondly, as part of my contribution to the team, I evaluated machine-learning to predict a person's seasonal temperature preferences by analyzing existing data from office workers. The third part of the research involved developing an algorithm that generated temperature setpoints based on outdoor temperature. My study compared the simulated energy use using these setpoints to that using the setpoints of a programmable thermostat. Finally, I developed and tested a user interface for a thermostat and in-home energy display. This research tested the effects of both energy versus price information and the context of sponsorship on the behavior of subjects. I also surveyed subjects on the usefulness of various displays. The wireless network succeeded in providing detailed data to enable an intelligent controller and provide feedback to the users. The learning algorithm showed mixed results. The adaptive temperature setpoints saved energy in both annual and summertime simulations. The context in which I introduced the DREAM interface affected behavior, but the type of information displayed did not. The subjects responded that appliance-level feedback and tools that provided choices would be useful in a dynamic tariff environment.
Wallis, D J; Hetherington, M M
2004-08-01
Restrained and emotional eaters overeat in response to stress. To compare differential effects of cognitive demand and ego-threatening stressors on subsequent chocolate intake, 38 females completed a neutral (control), an ego threatening and an incongruent Stroop colour-naming task on three separate occasions. Participants were assigned to four groups based on median-split scores on the restrained and emotional eating scales of the Dutch Eating Behaviour Questionnaire-high restraint/high emotional, high restraint/low emotional, low restraint/high emotional and low restraint/low emotional. Higher response latencies were observed in the incongruent task, confirming its greater cognitive (attentional) demand. Overall intake was enhanced by 23% after ego-threat and 15% after the incongruent Stroop task relative to control. Restraint was associated with greater intake after both ego-threat and the incongruent task than in the control condition. In contrast, emotional eating was associated with greater intake after only the ego-threat, relative to control. A positive association between reaction time and subsequent intake in all conditions for high restraint/low emotional eaters provided support for the limited capacity hypothesis. Enhanced intake in emotional eaters is proposed to relate to escape from self-awareness. These findings demonstrate differential effects of threat and demand on stress-related eating in restrained and emotional eaters.
Feeding styles and child weight status among recent immigrant mother-child dyads
2012-01-01
Background Research has shown that parental feeding styles may influence children’s food consumption, energy intake, and ultimately, weight status. We examine this relationship, among recent immigrants to the US. Given that immigrant parents and children are at greater risk for becoming overweight/obese with increased time in the US, identification of risk factors for weight gain is critical. Methods Baseline data was collected on 383 mother-child dyads enrolled in Live Well, a community-based, participatory, randomized controlled lifestyle intervention to prevent weight gain in recent immigrant mothers. Socio-demographic information together with heights and weights were collected for both mother and child. Acculturation, behavioral data, and responses to the Caregiver’s Feeding Styles Questionnaire (CFSQ) were also obtained from the mother. Results The children’s average age was 6.2 ± 2.7 years, 58% male. Mothers had been in the country for an average of 6.0 ± 3.3 years, and are Brazilian (36%), Haitian (34%) and Latino (30%). Seventy-two percent of the mothers were overweight/obese, while 43% of the children were overweight/obese. Fifteen percent of mothers reported their feeding style as being high demanding/high responsive; 32% as being high demanding/low responsive; 34% as being low demanding/high responsive and 18% as being low demanding/low responsive. In bivariate analyses, feeding styles significantly differed by child BMIz-score, ethnic group, and mother’s perceived stress. In multiple linear regression, a low demanding/high responsive feeding style was found to be positively associated (ß = 0.56) with a higher child weight as compared to high demanding/high responsive, controlling for known covariates (p = 0.01). Conclusions Most mothers report having a low demanding/high responsive feeding style, which is associated with higher child weight status in this diverse immigrant population. This finding adds to the growing literature that suggests this type of feeding style may be a risk factor for childhood obesity. Further research is needed to help understand the larger socio-cultural context and its influence on feeding dynamics among immigrant families and families of lower incomes. How parents establish a certain feeding style in their home country compared to when they move to the US “obesogenic” environment, should also be explored. PMID:22642962
Effect of Cognitive Demand on Functional Visual Field Performance in Senior Drivers with Glaucoma.
Gangeddula, Viswa; Ranchet, Maud; Akinwuntan, Abiodun E; Bollinger, Kathryn; Devos, Hannes
2017-01-01
Purpose: To investigate the effect of cognitive demand on functional visual field performance in drivers with glaucoma. Method: This study included 20 drivers with open-angle glaucoma and 13 age- and sex-matched controls. Visual field performance was evaluated under different degrees of cognitive demand: a static visual field condition (C1), dynamic visual field condition (C2), and dynamic visual field condition with active driving (C3) using an interactive, desktop driving simulator. The number of correct responses (accuracy) and response times on the visual field task were compared between groups and between conditions using Kruskal-Wallis tests. General linear models were employed to compare cognitive workload, recorded in real-time through pupillometry, between groups and conditions. Results: Adding cognitive demand (C2 and C3) to the static visual field test (C1) adversely affected accuracy and response times, in both groups ( p < 0.05). However, drivers with glaucoma performed worse than did control drivers when the static condition changed to a dynamic condition [C2 vs. C1 accuracy; glaucoma: median difference (Q1-Q3) 3 (2-6.50) vs. 2 (0.50-2.50); p = 0.05] and to a dynamic condition with active driving [C3 vs. C1 accuracy; glaucoma: 2 (2-6) vs. 1 (0.50-2); p = 0.02]. Overall, drivers with glaucoma exhibited greater cognitive workload than controls ( p = 0.02). Conclusion: Cognitive demand disproportionately affects functional visual field performance in drivers with glaucoma. Our results may inform the development of a performance-based visual field test for drivers with glaucoma.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Xiangqi; Wang, Jiyu; Mulcahy, David
This paper presents a voltage-load sensitivity matrix (VLSM) based voltage control method to deploy demand response resources for controlling voltage in high solar penetration distribution feeders. The IEEE 123-bus system in OpenDSS is used for testing the performance of the preliminary VLSM-based voltage control approach. A load disaggregation process is applied to disaggregate the total load profile at the feeder head to each load nodes along the feeder so that loads are modeled at residential house level. Measured solar generation profiles are used in the simulation to model the impact of solar power on distribution feeder voltage profiles. Different casemore » studies involving various PV penetration levels and installation locations have been performed. Simulation results show that the VLSM algorithm performance meets the voltage control requirements and is an effective voltage control strategy.« less
Harding, Ian H; Yücel, Murat; Harrison, Ben J; Pantelis, Christos; Breakspear, Michael
2015-02-01
Cognitive control and working memory rely upon a common fronto-parietal network that includes the inferior frontal junction (IFJ), dorsolateral prefrontal cortex (dlPFC), pre-supplementary motor area/dorsal anterior cingulate cortex (pSMA/dACC), and intraparietal sulcus (IPS). This network is able to flexibly adapt its function in response to changing behavioral goals, mediating a wide range of cognitive demands. Here we apply dynamic causal modeling to functional magnetic resonance imaging data to characterize task-related alterations in the strength of network interactions across distinct cognitive processes. Evidence in favor of task-related connectivity dynamics was accrued across a very large space of possible network structures. Cognitive control and working memory demands were manipulated using a factorial combination of the multi-source interference task and a verbal 2-back working memory task, respectively. Both were found to alter the sensitivity of the IFJ to perceptual information, and to increase IFJ-to-pSMA/dACC connectivity. In contrast, increased connectivity from the pSMA/dACC to the IPS, as well as from the dlPFC to the IFJ, was uniquely driven by cognitive control demands; a task-induced negative influence of the dlPFC on the pSMA/dACC was specific to working memory demands. These results reflect a system of both shared and unique context-dependent dynamics within the fronto-parietal network. Mechanisms supporting cognitive engagement, response selection, and action evaluation may be shared across cognitive domains, while dynamic updating of task and context representations within this network are potentially specific to changing demands on cognitive control. Copyright © 2014 Elsevier Inc. All rights reserved.
Rey, Gwladys; Desseilles, Martin; Favre, Sophie; Dayer, Alexandre; Piguet, Camille; Aubry, Jean-Michel; Vuilleumier, Patrik
2014-08-30
We used functional magnetic resonance imaging (fMRI) to examine affective control longitudinally in a group of patients with bipolar disorder (BD). Participants comprised 12 BD patients who underwent repeated fMRI scans in euthymic (n=11), depressed (n=9), or hypomanic (n=9) states, and were compared with 12 age-matched healthy controls. During fMRI, participants performed an emotional face-word interference task with either low or high attentional demands. Relative to healthy controls, patients showed decreased activation of the cognitive control network normally associated with conflict processing, more severely during hypomania than during depression, but regardless of level of task demand in both cases. During euthymia, a decreased response to conflict was observed only during the high load condition. Additionally, unlike healthy participants, patients exhibited deactivation in several key areas in response to emotion-conflict trials - including the rostral anterior cingulate cortex during euthymia, the hippocampus during depression, and the posterior cingulate cortex during hypomania. Our results indicate that the ability of BD patients to recruit control networks when processing affective conflict, and the abnormal suppression of activity in distinct components of the default mode network, may depend on their current clinical state and attentional demand. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands.
Setoh, Peipei; Scott, Rose M; Baillargeon, Renée
2016-11-22
When tested with traditional false-belief tasks, which require answering a standard question about the likely behavior of an agent with a false belief, children perform below chance until age 4 y or later. When tested without such questions, however, children give evidence of false-belief understanding much earlier. Are traditional tasks difficult because they tap a more advanced form of false-belief understanding (fundamental-change view) or because they impose greater processing demands (processing-demands view)? Evidence that young children succeed at traditional false-belief tasks when processing demands are reduced would support the latter view. In prior research, reductions in inhibitory-control demands led to improvements in young children's performance, but often only to chance (instead of below-chance) levels. Here we examined whether further reductions in processing demands might lead to success. We speculated that: (i) young children could respond randomly in a traditional low-inhibition task because their limited information-processing resources are overwhelmed by the total concurrent processing demands in the task; and (ii) these demands include those from the response-generation process activated by the standard question. This analysis suggested that 2.5-y-old toddlers might succeed at a traditional low-inhibition task if response-generation demands were also reduced via practice trials. As predicted, toddlers performed above chance following two response-generation practice trials; toddlers failed when these trials either were rendered less effective or were used in a high-inhibition task. These results support the processing-demands view: Even toddlers succeed at a traditional false-belief task when overall processing demands are reduced.
Cognitive Load Differentially Impacts Response Control in Girls and Boys with ADHD
Mostofsky, Stewart H.; Rosch, Keri S.
2015-01-01
Children with attention-deficit hyperactivity disorder (ADHD) consistently show impaired response control, including deficits in response inhibition and increased intrasubject variability (ISV) compared to typically-developing (TD) children. However, significantly less research has examined factors that may influence response control in individuals with ADHD, such as task or participant characteristics. The current study extends the literature by examining the impact of increasing cognitive demands on response control in a large sample of 81children with ADHD (40 girls) and 100 TD children (47 girls), ages 8–12 years. Participants completed a simple Go/No-Go (GNG) task with minimal cognitive demands, and a complex GNG task with increased cognitive load. Results showed that increasing cognitive load differentially impacted response control (commission error rate and tau, an ex-Gaussian measure of ISV) for girls, but not boys, with ADHD compared to same-sex TD children. Specifically, a sexually dimorphic pattern emerged such that boys with ADHD demonstrated higher commission error rate and tau on both the simple and complex GNG tasks as compared to TD boys, whereas girls with ADHD did not differ from TD girls on the simple GNG task, but showed higher commission error rate and tau on the complex GNG task. These findings suggest that task complexity influences response control in children with ADHD in a sexually dimorphic manner. The findings have substantive implications for the pathophysiology of ADHD in boys versus girls with ADHD. PMID:25624066
A Validity-Based Approach to Quality Control and Assurance of Automated Scoring
ERIC Educational Resources Information Center
Bejar, Isaac I.
2011-01-01
Automated scoring of constructed responses is already operational in several testing programmes. However, as the methodology matures and the demand for the utilisation of constructed responses increases, the volume of automated scoring is likely to increase at a fast pace. Quality assurance and control of the scoring process will likely be more…
Approaches to Enable Demand Response by Industrial Loads for Ancillary Services Provision
NASA Astrophysics Data System (ADS)
Zhang, Xiao
Demand response has gained significant attention in recent years as it demonstrates potentials to enhance the power system's operational flexibility in a cost-effective way. Industrial loads such as aluminum smelters, steel manufacturers, and cement plants demonstrate advantages in supporting power system operation through demand response programs, because of their intensive power consumption, already existing advanced monitoring and control infrastructure, and the strong economic incentive due to the high energy costs. In this thesis, we study approaches to efficiently integrate each of these types of manufacturing processes as demand response resources. The aluminum smelting process is able to change its power consumption both accurately and quickly by controlling the pots' DC voltage, without affecting the production quality. Hence, an aluminum smelter has both the motivation and the ability to participate in demand response. First, we focus on determining the optimal regulation capacity that such a manufacturing plant should provide. Next, we focus on determining its optimal bidding strategy in the day-ahead energy and ancillary services markets. Electric arc furnaces (EAFs) in steel manufacturing consume a large amount of electric energy. However, a steel plant can take advantage of time-based electricity prices by optimally arranging energy-consuming activities to avoid peak hours. We first propose scheduling methods that incorporate the EAFs' flexibilities to reduce the electricity cost. We then propose methods to make the computations more tractable. Finally, we extend the scheduling formulations to enable the provision of spinning reserve. Cement plants are able to quickly adjust their power consumption rate by switching on/off the crushers. However, switching on/off the loading units only achieves discrete power changes, which restricts the load from offering valuable ancillary services such as regulation and load following, as continuous power changes are required for these services. We propose methods that enable these services with the support of an on-site energy storage device. As demonstrated by the case studies, the proposed approaches are effective and can generate practical production instructions for the industrial loads. This thesis not only provides methods to enable demand response by industrial loads but also potentially encourages industrial loads to be active in electricity markets.
Vagal and sympathetic activity in burnouts during a mentally demanding workday.
Zanstra, Ydwine J; Schellekens, Jan M H; Schaap, Cas; Kooistra, Libbe
2006-01-01
We study differences in task performance and related sympathetic-vagal reaction patterns between burnouts and controls during a mentally demanding workday. Thirty-nine adults with burnout and 40 healthy controls performed mental tasks during a simulated workday. At pretest, just before lunch (lunch test) and at the end of the day (posttest), a Stroop color word task was administered as a probe task. Efficiency (the relation between performance and effort during the probe task), performance (reaction time and errors), and effort (self-report) were measured, as well as cardiovascular indices of sympathetic (blood pressure) and vagal (respiratory sinus arrhythmia) activity. Performance and effort investment of both burnouts and controls did not differ during pretest. As the day progressed the performance of controls improved more than the performance of burnouts. Moreover, the control group showed a decrease of blood pressure in response to mental task demands, a decrease in respiratory sinus arrhythmia activity, and no change in experienced effort. In the burnout group, no change could be demonstrated in blood pressure, suggesting a sympathetic predominance in the sympathetic-vagal balance. Burnouts experienced an increase in effort and were more tired at the end of the workday. Burnouts and healthy controls differ in their pattern of sympathetic-vagal activity only after long-lasting work demands. Findings give limited support to Porges's view that in healthy subjects, the vagal system is more responsive to challenging task situations than in chronically stressed individuals. The distinction between two phases in the burnout on the basis of behavioral and physiological characteristics is discussed.
Fitzgerald, Daniel A.; Piejko, Katherine; Roberts, Julia; Kennedy, Amy E.; Phan, K. Luan
2016-01-01
Generalized social anxiety disorder (gSAD) is associated with aberrant anterior cingulate cortex (ACC) response to threat distractors. Perceptual load has been shown to modulate ACC activity such that under high load, when demands on processing capacity is restricted, individuals with gSAD exhibit compensatory activation to threat distractors yet under low load, there is evidence of reduced activation. It is not known if neural predictors of response to cognitive behavioral therapy (CBT), based on such emotional conflict resolution, interact with demands on controlled processes. Prior to CBT, 32 patients with gSAD completed an fMRI task involving a target letter in a string of identical targets (low perceptual load) or a target letter in a mixed letter string (high perceptual load) superimposed on fearful, angry and neutral face distractors. Whole-brain voxel-wise analyses revealed better CBT outcome was predicted by more frontopartial activity that included dorsal ACC (dACC) and insula to threat (vs neutral) distractors during high, but not low, perceptual load. Psychophysiological interaction analysis with dACC as the seed region revealed less connectivity with dorsolateral prefrontal cortex to threat distractors during high load. Results indicate patients with less regulatory capability when demands on higher-order control are great may benefit more from CBT. PMID:26634281
The role of the anterior cingulate cortex in the affective evaluation of conflict
Braem, Senne; King, Joseph A.; Korb, Franziska M.; Krebs, Ruth M.; Notebaert, Wim; Egner, Tobias
2017-01-01
An influential theory of anterior cingulate cortex (ACC) function argues that this brain region plays a crucial role in the affective evaluation of performance monitoring and control demands. Specifically, control-demanding processes such as response conflict, are thought to be registered as aversive signals by the ACC, which in turn triggers processing adjustments to support avoidance-learning. In support of conflict being treated as an aversive event, recent behavioural studies demonstrated that incongruent (i.e., conflict-inducing) relative to congruent stimuli can speed up subsequent negative relative to positive affective picture processing. Here, we used functional magnetic resonance imaging (fMRI) to investigate directly whether ACC activity in response to negative versus positive pictures is modulated by preceding control demands, consisting of conflict and task-switching conditions. The results show that negative relative to positive pictures elicited higher ACC activation following congruent relative to incongruent trials, suggesting that the ACC’s response to negative (positive) pictures was indeed affectively primed by incongruent (congruent) trials. Interestingly, this pattern of results was observed on task repetitions, but disappeared on task alternations. Our findings support the proposal that conflict induces negative affect, and are the first to show that this affective signal is reflected in ACC activation. PMID:27575278
dos Santos, Karoliny; Gulart, Aline A.; Munari, Anelise B.; Karloh, Manuela; Mayer, Anamaria F.
2016-01-01
ABSTRACT Background Airflow limitation frequently leads to the interruption of activities of daily living (ADL) in patients with Chronic Obstructive Pulmonary Disease (COPD). These patients commonly show absence of ventilatory reserve, reduced inspiratory reserve volume, and dynamic hyperinflation (DH). Objective To investigate ventilatory response and DH induced by three ADL-based protocols in COPD patients and compare them to healthy subjects. Method Cross-sectional study. COPD group: 23 patients (65±6 years, FEV1 37.2±15.4%pred); control group: 14 healthy subjects (64±4 years) matched for age, sex, and body mass index. Both groups performed all three tests: Glittre-ADL test; an activity test that involved moving objects on a shelf (TSHELF); and a modified shelf protocol isolating activity with upper limbs (TSHELF-M). Ventilatory response and inspiratory capacity were evaluated. Results Baseline ventilatory variables were similar between groups (p>0.05). The ventilatory demand increased and the inspiratory capacity decreased significantly at the end of the tests in the COPD group. Ventilatory demand and DH were higher (p<0.05) in the TSHELF than in the TSHELF–M in the COPD group (p<0.05). There were no differences in DH between the three tests in the control group (p>0.05) and ventilatory demand increased at the end of the tests (p<0.05) but to a lower extent than the COPD group. Conclusion The TSHELF induces similar ventilatory responses to the Glittre-ADL test in COPD patients with higher ventilatory demand and DH. In contrast, the ventilatory response was attenuated in the TSHELF-M, suggesting that squatting and bending down during the Glittre-ADL test could trigger significant ventilatory overload. PMID:27333482
Medaglia, John D; Harvey, Denise Y; White, Nicole; Kelkar, Apoorva; Zimmerman, Jared; Bassett, Danielle S; Hamilton, Roy H
2018-06-08
In language production, humans are confronted with considerable word selection demands. Often, we must select a word from among similar, acceptable, and competing alternative words in order to construct a sentence that conveys an intended meaning. In recent years, the left inferior frontal gyrus (LIFG) has been identified as critical to this ability. Despite a recent emphasis on network approaches to understanding language, how the LIFG interacts with the brain's complex networks to facilitate controlled language performance remains unknown. Here, we take a novel approach to understand word selection as a network control process in the brain. Using an anatomical brain network derived from high-resolution diffusion spectrum imaging (DSI), we computed network controllability underlying the site of transcranial magnetic stimulation in the LIFG between administrations of language tasks that vary in response (cognitive control) demands: open-response (word generation) vs. closed-response (number naming) tasks. We find that a statistic that quantifies the LIFG's theoretically predicted control of communication across modules in the human connectome explains TMS-induced changes in open-response language task performance only. Moreover, we find that a statistic that quantifies the LIFG's theoretically predicted control of difficult-to-reach states explains vulnerability to TMS in the closed-ended (but not open-ended) response task. These findings establish a link between network controllability, cognitive function, and TMS effects. SIGNIFICANCE STATEMENT This work illustrates that network control statistics applied to anatomical connectivity data demonstrate relationships with cognitive variability during controlled language tasks and TMS effects. Copyright © 2018 the authors.
Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands
Scott, Rose M.; Baillargeon, Renée
2016-01-01
When tested with traditional false-belief tasks, which require answering a standard question about the likely behavior of an agent with a false belief, children perform below chance until age 4 y or later. When tested without such questions, however, children give evidence of false-belief understanding much earlier. Are traditional tasks difficult because they tap a more advanced form of false-belief understanding (fundamental-change view) or because they impose greater processing demands (processing-demands view)? Evidence that young children succeed at traditional false-belief tasks when processing demands are reduced would support the latter view. In prior research, reductions in inhibitory-control demands led to improvements in young children’s performance, but often only to chance (instead of below-chance) levels. Here we examined whether further reductions in processing demands might lead to success. We speculated that: (i) young children could respond randomly in a traditional low-inhibition task because their limited information-processing resources are overwhelmed by the total concurrent processing demands in the task; and (ii) these demands include those from the response-generation process activated by the standard question. This analysis suggested that 2.5-y-old toddlers might succeed at a traditional low-inhibition task if response-generation demands were also reduced via practice trials. As predicted, toddlers performed above chance following two response-generation practice trials; toddlers failed when these trials either were rendered less effective or were used in a high-inhibition task. These results support the processing-demands view: Even toddlers succeed at a traditional false-belief task when overall processing demands are reduced. PMID:27821728
Zhang, Haoyun; Eppes, Anna; Beatty-Martínez, Anne; Navarro-Torres, Christian; Diaz, Michele T
2018-06-19
Language production and cognitive control are complex processes that involve distinct yet interacting brain networks. However, the extent to which these processes interact and their neural bases have not been thoroughly examined. Here, we investigated the neural and behavioral bases of language production and cognitive control via a phonological go/no-go picture-naming task. Naming difficulty and cognitive control demands (i.e., conflict monitoring and response inhibition) were manipulated by varying the proportion of naming trials (go trials) and inhibition trials (no-go trials) across task runs. The results demonstrated that as task demands increased, participants' behavioral performance declined (i.e., longer reaction times on naming trials, more commission errors on inhibition trials) whereas brain activation generally increased. Increased activation was found not only within the language network but also in domain-general control regions. Additionally, right superior and inferior frontal and left supramarginal gyri were sensitive to increased task difficulty during both language production and response inhibition. We also found both positive and negative brain-behavior correlations. Most notably, increased activation in sensorimotor regions, such as precentral and postcentral gyri, was associated with better behavioral performance, in both successful picture naming and successful inhibition. Moreover, comparing the strength of correlations across conditions indicated that the brain-behavior correlations in sensorimotor regions that were associated with improved performance became stronger as task demands increased. Overall, our results suggest that cognitive control demands affect language production, and that successfully coping with increases in task difficulty relies on both language-specific and domain-general cognitive control regions.
ERIC Educational Resources Information Center
Dreisbach, Gesine; Fischer, Rico
2012-01-01
Theories of human action control deal with the question of how cognitive control is dynamically adjusted to task demands. The conflict monitoring theory of anterior cingulate (ACC) function suggests that the ACC monitors for response conflicts in the ongoing processing stream thereby triggering the mobilization of cognitive control. Alternatively,…
Evaluating Job Demands and Control Measures for Use in Farm Worker Health Surveillance.
Alterman, Toni; Gabbard, Susan; Grzywacz, Joseph G; Shen, Rui; Li, Jia; Nakamoto, Jorge; Carroll, Daniel J; Muntaner, Carles
2015-10-01
Workplace stress likely plays a role in health disparities; however, applying standard measures to studies of immigrants requires thoughtful consideration. The goal of this study was to determine the appropriateness of two measures of occupational stressors ('decision latitude' and 'job demands') for use with mostly immigrant Latino farm workers. Cross-sectional data from a pilot module containing a four-item measure of decision latitude and a two-item measure of job demands were obtained from a subsample (N = 409) of farm workers participating in the National Agricultural Workers Survey. Responses to items for both constructs were clustered toward the low end of the structured response-set. Percentages of responses of 'very often' and 'always' for each of the items were examined by educational attainment, birth country, dominant language spoken, task, and crop. Cronbach's α, when stratified by subgroups of workers, for the decision latitude items were (0.65-0.90), but were less robust for the job demands items (0.25-0.72). The four-item decision latitude scale can be applied to occupational stress research with immigrant farm workers, and potentially other immigrant Latino worker groups. The short job demands scale requires further investigation and evaluation before suggesting widespread use.
On-demand control of microfluidic flow via capillary-tuned solenoid microvalve suction.
Zhang, Qiang; Zhang, Peiran; Su, Yetian; Mou, Chunbo; Zhou, Teng; Yang, Menglong; Xu, Jian; Ma, Bo
2014-12-21
A simple, low-cost and on-demand microfluidic flow controlling platform was developed based on a unique capillary-tuned solenoid microvalve suction effect without any outer pressure source. The suction effect was innovatively employed as a stable and controllable driving force for the manipulation of the microfluidic system by connecting a piece of capillary between the microvalve and the microfluidic chip, which caused significant hydrodynamic resistance differences among the solenoid valve ports and changed the flowing mode inside the valve. The volume of sucked liquid could be controlled from microliters even down to picoliters either by decreasing the valve energized duration (from a maximum energized duration to the valve response time of 20 ms) or by increasing the inserted capillary length (i.e., its hydrodynamic resistance). Several important microfluidic unit operations such as cell/droplet sorting and on-demand size-controllable droplet generation have been demonstrated on the developed platform and both simulations and experiments confirmed that this platform has good controllability and stability.
X-ray Radiation-Controlled NO-Release for On-Demand Depth-Independent Hypoxic Radiosensitization.
Fan, Wenpei; Bu, Wenbo; Zhang, Zhen; Shen, Bo; Zhang, Hui; He, Qianjun; Ni, Dalong; Cui, Zhaowen; Zhao, Kuaile; Bu, Jiwen; Du, Jiulin; Liu, Jianan; Shi, Jianlin
2015-11-16
Multifunctional stimuli-responsive nanotheranostic systems are highly desirable for realizing simultaneous biomedical imaging and on-demand therapy with minimized adverse effects. Herein, we present the construction of an intelligent X-ray-controlled NO-releasing upconversion nanotheranostic system (termed as PEG-USMSs-SNO) by engineering UCNPs with S-nitrosothiol (R-SNO)-grafted mesoporous silica. The PEG-USMSs-SNO is designed to respond sensitively to X-ray radiation for breaking down the S-N bond of SNO to release NO, which leads to X-ray dose-controlled NO release for on-demand hypoxic radiosensitization besides upconversion luminescent imaging through UCNPs in vitro and in vivo. Thanks to the high live-body permeability of X-ray, our developed PEG-USMSs-SNO may provide a new technique for achieving depth-independent controlled NO release and positioned radiotherapy enhancement against deep-seated solid tumors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, Jacob; Edgar, Thomas W.; Daily, Jeffrey A.
With an ever-evolving power grid, concerns regarding how to maintain system stability, efficiency, and reliability remain constant because of increasing uncertainties and decreasing rotating inertia. To alleviate some of these concerns, demand response represents a viable solution and is virtually an untapped resource in the current power grid. This work describes a hierarchical control framework that allows coordination between distributed energy resources and demand response. This control framework is composed of two control layers: a coordination layer that ensures aggregations of resources are coordinated to achieve system objectives and a device layer that controls individual resources to assure the predeterminedmore » power profile is tracked in real time. Large-scale simulations are executed to study the hierarchical control, requiring advancements in simulation capabilities. Technical advancements necessary to investigate and answer control interaction questions, including the Framework for Network Co-Simulation platform and Arion modeling capability, are detailed. Insights into the interdependencies of controls across a complex system and how they must be tuned, as well as validation of the effectiveness of the proposed control framework, are yielded using a large-scale integrated transmission system model coupled with multiple distribution systems.« less
NASA Technical Reports Server (NTRS)
Wickens, C.; Gill, R.; Kramer, A.; Ross, W.; Donchin, E.
1981-01-01
Three experiments are described in which tracking difficulty is varied in the presence of a covert tone discrimination task. Event related brain potentials (ERPs) elicited by the tones are employed as an index of the resource demands of tracking. The ERP measure reflected the control order variation, and this variable was thereby assumed to compete for perceptual/central processing resources. A fine-grained analysis of the results suggested that the primary demands of second order tracking involve the central processing operations of maintaining a more complex internal model of the dynamic system, rather than the perceptual demands of higher derivative perception. Experiment 3 varied tracking bandwidth in random input tracking, and the ERP was unaffected. Bandwidth was then inferred to compete for response-related processing resources that are independent of the ERP.
Cyber Physical System Modelling of Distribution Power Systems for Dynamic Demand Response
NASA Astrophysics Data System (ADS)
Chu, Xiaodong; Zhang, Rongxiang; Tang, Maosen; Huang, Haoyi; Zhang, Lei
2018-01-01
Dynamic demand response (DDR) is a package of control methods to enhance power system security. A CPS modelling and simulation platform for DDR in distribution power systems is presented in this paper. CPS modelling requirements of distribution power systems are analyzed. A coupled CPS modelling platform is built for assessing DDR in the distribution power system, which combines seamlessly modelling tools of physical power networks and cyber communication networks. Simulations results of IEEE 13-node test system demonstrate the effectiveness of the modelling and simulation platform.
Raising Competent Kids: The Authoritative Parenting Style. For Parents Particularly.
ERIC Educational Resources Information Center
Ballantine, Jeanne
2001-01-01
Suggests that the authoritative parenting style without physical punishment produces more positive results and fewest children's problems. Identifies age-appropriate authoritative responses: demanding and responsive; controlling but not restrictive; high parent involvement; participating actively with child's life; communicating openly; following…
The effects of arousal reappraisal on stress responses, performance and attention.
Sammy, Nadine; Anstiss, Paul A; Moore, Lee J; Freeman, Paul; Wilson, Mark R; Vine, Samuel J
2017-11-01
This study examined the effects of arousal reappraisal on cardiovascular responses, demand and resource evaluations, self-confidence, performance and attention under pressurized conditions. A recent study by Moore et al. [2015. Reappraising threat: How to optimize performance under pressure. Journal of Sport and Exercise Psychology, 37(3), 339-343. doi: 10.1123/jsep.2014-0186 ] suggested that arousal reappraisal is beneficial to the promotion of challenge states and leads to improvements in single-trial performance. This study aimed to further the work of Moore and colleagues (2015) by examining the effects of arousal reappraisal on cardiovascular responses, demand and resource evaluations, self-confidence, performance and attention in a multi-trial pressurized performance situation. Participants were randomly assigned to either an arousal reappraisal intervention or control condition, and completed a pressurized dart throwing task. The intervention encouraged participants to view their physiological arousal as facilitative rather than debilitative to performance. Measures of cardiovascular reactivity, demand and resource evaluations, self-confidence, task performance and attention were recorded. The reappraisal group displayed more favorable cardiovascular reactivity and reported higher resource evaluations and higher self-confidence than the control group but no task performance or attention effects were detected. These findings demonstrate the strength of arousal reappraisal in promoting adaptive stress responses, perceptions of resources and self-confidence.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Auslander, David; Culler, David; Wright, Paul
The goal of the 2.5 year Distributed Intelligent Automated Demand Response (DIADR) project was to reduce peak electricity load of Sutardja Dai Hall at UC Berkeley by 30% while maintaining a healthy, comfortable, and productive environment for the occupants. We sought to bring together both central and distributed control to provide “deep” demand response1 at the appliance level of the building as well as typical lighting and HVAC applications. This project brought together Siemens Corporate Research and Siemens Building Technology (the building has a Siemens Apogee Building Automation System (BAS)), Lawrence Berkeley National Laboratory (leveraging their Open Automated Demand Responsemore » (openADR), Auto-Demand Response, and building modeling expertise), and UC Berkeley (related demand response research including distributed wireless control, and grid-to-building gateway development). Sutardja Dai Hall houses the Center for Information Technology Research in the Interest of Society (CITRIS), which fosters collaboration among industry and faculty and students of four UC campuses (Berkeley, Davis, Merced, and Santa Cruz). The 141,000 square foot building, occupied in 2009, includes typical office spaces and a nanofabrication laboratory. Heating is provided by a district heating system (steam from campus as a byproduct of the campus cogeneration plant); cooling is provided by one of two chillers: a more typical electric centrifugal compressor chiller designed for the cool months (Nov- March) and a steam absorption chiller for use in the warm months (April-October). Lighting in the open office areas is provided by direct-indirect luminaries with Building Management System-based scheduling for open areas, and occupancy sensors for private office areas. For the purposes of this project, we focused on the office portion of the building. Annual energy consumption is approximately 8053 MWh; the office portion is estimated as 1924 MWh. The maximum peak load during the study period was 1175 kW. Several new tools facilitated this work, such as the Smart Energy Box, the distributed load controller or Energy Information Gateway, the web-based DR controller (dubbed the Central Load-Shed Coordinator or CLSC), and the Demand Response Capacity Assessment & Operation Assistance Tool (DRCAOT). In addition, an innovative data aggregator called sMAP (simple Measurement and Actuation Profile) allowed data from different sources collected in a compact form and facilitated detailed analysis of the building systems operation. A smart phone application (RAP or Rapid Audit Protocol) facilitated an inventory of the building’s plug loads. Carbon dioxide sensors located in conference rooms and classrooms allowed demand controlled ventilation. The extensive submetering and nimble access to this data provided great insight into the details of the building operation as well as quick diagnostics and analyses of tests. For example, students discovered a short-cycling chiller, a stuck damper, and a leaking cooling coil in the first field tests. For our final field tests, we were able to see how each zone was affected by the DR strategies (e.g., the offices on the 7th floor grew very warm quickly) and fine-tune the strategies accordingly.« less
Umehara, Katsura; Ohya, Yukihiro; Kawakami, Norito; Tsutsumi, Akizumi; Fujimura, Masanori
2007-11-01
A cross-sectional study was conducted to explore what work-related factors were associated with job stress among pediatricians in Japan, as determined by the demand-control-support model and psychosomatic symptoms. We sent an anonymous questionnaire to a random sample of 3,000 members selected from the nationwide register of the Japan Pediatric Society and received 850 responses (response rate, 28%). Data from the 590 respondents who worked more than 35 h per week as a pediatrician and had no missing responses in the questionnaire were analyzed. We measured workload-related variables (e.g. working hours, work schedule) and recovery-related variables (e.g. workdays with no overtime, days off with no work in the past month) as exposure variables, and psychosocial job stressors (the Brief Job Stress Questionnaire) and psychosomatic symptoms as outcome variables. Longer working hours per week was significantly associated with greater job demand, lower job control and more psychosomatic symptoms (p<0.05). After adjusting for working hours, more workdays with no overtime was significantly associated with lower job demand, greater job control and fewer psychosomatic symptoms (p<0.05). Our findings suggest that long working hours is a risk factor for job stressors and psychosomatic symptoms, and that workdays with no overtime is a protective factor which may facilitate recovery. Controlling working hours and encouraging non-overtime workdays may be important for reducing job stressors and psychosomatic symptoms among pediatricians in Japan.
A leptin-regulated circuit controls glucose mobilization during noxious stimuli.
Flak, Jonathan N; Arble, Deanna; Pan, Warren; Patterson, Christa; Lanigan, Thomas; Goforth, Paulette B; Sacksner, Jamie; Joosten, Maja; Morgan, Donald A; Allison, Margaret B; Hayes, John; Feldman, Eva; Seeley, Randy J; Olson, David P; Rahmouni, Kamal; Myers, Martin G
2017-08-01
Adipocytes secrete the hormone leptin to signal the sufficiency of energy stores. Reductions in circulating leptin concentrations reflect a negative energy balance, which augments sympathetic nervous system (SNS) activation in response to metabolically demanding emergencies. This process ensures adequate glucose mobilization despite low energy stores. We report that leptin receptor-expressing neurons (LepRb neurons) in the periaqueductal gray (PAG), the largest population of LepRb neurons in the brain stem, mediate this process. Application of noxious stimuli, which often signal the need to mobilize glucose to support an appropriate response, activated PAG LepRb neurons, which project to and activate parabrachial nucleus (PBN) neurons that control SNS activation and glucose mobilization. Furthermore, activating PAG LepRb neurons increased SNS activity and blood glucose concentrations, while ablating LepRb in PAG neurons augmented glucose mobilization in response to noxious stimuli. Thus, decreased leptin action on PAG LepRb neurons augments the autonomic response to noxious stimuli, ensuring sufficient glucose mobilization during periods of acute demand in the face of diminished energy stores.
Dissociating response conflict and error likelihood in anterior cingulate cortex.
Yeung, Nick; Nieuwenhuis, Sander
2009-11-18
Neuroimaging studies consistently report activity in anterior cingulate cortex (ACC) in conditions of high cognitive demand, leading to the view that ACC plays a crucial role in the control of cognitive processes. According to one prominent theory, the sensitivity of ACC to task difficulty reflects its role in monitoring for the occurrence of competition, or "conflict," between responses to signal the need for increased cognitive control. However, a contrasting theory proposes that ACC is the recipient rather than source of monitoring signals, and that ACC activity observed in relation to task demand reflects the role of this region in learning about the likelihood of errors. Response conflict and error likelihood are typically confounded, making the theories difficult to distinguish empirically. The present research therefore used detailed computational simulations to derive contrasting predictions regarding ACC activity and error rate as a function of response speed. The simulations demonstrated a clear dissociation between conflict and error likelihood: fast response trials are associated with low conflict but high error likelihood, whereas slow response trials show the opposite pattern. Using the N2 component as an index of ACC activity, an EEG study demonstrated that when conflict and error likelihood are dissociated in this way, ACC activity tracks conflict and is negatively correlated with error likelihood. These findings support the conflict-monitoring theory and suggest that, in speeded decision tasks, ACC activity reflects current task demands rather than the retrospective coding of past performance.
Optimal Load-Side Control for Frequency Regulation in Smart Grids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Changhong; Mallada, Enrique; Low, Steven
Frequency control rebalances supply and demand while maintaining the network state within operational margins. It is implemented using fast ramping reserves that are expensive and wasteful, and which are expected to become increasingly necessary with the current acceleration of renewable penetration. The most promising solution to this problem is the use of demand response, i.e., load participation in frequency control. Yet it is still unclear how to efficiently integrate load participation without introducing instabilities and violating operational constraints. In this paper, we present a comprehensive load-side frequency control mechanism that can maintain the grid within operational constraints. In particular, ourmore » controllers can rebalance supply and demand after disturbances, restore the frequency to its nominal value, and preserve interarea power flows. Furthermore, our controllers are distributed (unlike the currently implemented frequency control), can allocate load updates optimally, and can maintain line flows within thermal limits. We prove that such a distributed load-side control is globally asymptotically stable and robust to unknown load parameters. We illustrate its effectiveness through simulations.« less
An adaptive load-following control system for a space nuclear power system
NASA Astrophysics Data System (ADS)
Metzger, John D.; El-Genk, Mohamed S.
An adaptive load-following control system is proposed for a space nuclear power system. The conceptual design of the SP-100 space nuclear power system proposes operating the nuclear reactor at a base thermal power and accommodating changes in the electrical power demand with a shunt regulator. It is necessary to increase the reactor thermal power if the payload electrical demand exceeds the peak system electrical output for the associated reactor power. When it is necessary to change the nuclear reactor power to meet a change in the power demand, the power ascension or descension must be accomplished in a predetermined manner to avoid thermal stresses in the system and to achieve the desired reactor period. The load-following control system described has the ability to adapt to changes in the system and to changes in the satellite environment. The application is proposed of the model reference adaptive control (MRAC). The adaptive control system has the ability to control the dynamic response of nonlinear systems. Three basic subsets of adaptive control are: (1) gain scheduling, (2) self-tuning regulators, and (3) model reference adaptive control.
Analysis of Discrete Stated Responses to Parking Pricing Based Transportation Control Measures
DOT National Transportation Integrated Search
1997-01-01
The realization that one can no longer build out of congestion while preserving the urban environment has led to an increasing interest in the potential application of transportation control measures (TCM) for curbing travel demand. One such TCM that...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hale, Elaine
Demand response may be a valuable flexible resource for low-carbon electric power grids. However, there are as many types of possible demand response as there are ways to use electricity, making demand response difficult to study at scale in realistic settings. This talk reviews our state of knowledge regarding the potential value of demand response in several example systems as a function of increasing levels of wind and solar power, sometimes drawing on the analogy between demand response and storage. Overall, we find demand response to be promising, but its potential value is very system dependent. Furthermore, demand response, likemore » storage, can easily saturate ancillary service markets.« less
Slay, Christopher E; Enok, Sanne; Hicks, James W; Wang, Tobias
2014-05-15
Physiological cardiac hypertrophy is characterized by reversible enlargement of cardiomyocytes and changes in chamber architecture, which increase stroke volume and via augmented convective oxygen transport. Cardiac hypertrophy is known to occur in response to repeated elevations of O2 demand and/or reduced O2 supply in several species of vertebrate ectotherms, including postprandial Burmese pythons (Python bivittatus). Recent data suggest postprandial cardiac hypertrophy in P. bivittatus is a facultative rather than obligatory response to digestion, though the triggers of this response are unknown. Here, we hypothesized that an O2 supply-demand mismatch stimulates postprandial cardiac enlargement in Burmese pythons. To test this hypothesis, we rendered animals anemic prior to feeding, essentially halving blood oxygen content during the postprandial period. Fed anemic animals had heart rates 126% higher than those of fasted controls, which, coupled with a 71% increase in mean arterial pressure, suggests fed anemic animals were experiencing significantly elevated cardiac work. We found significant cardiac hypertrophy in fed anemic animals, which exhibited ventricles 39% larger than those of fasted controls and 28% larger than in fed controls. These findings support our hypothesis that those animals with a greater magnitude of O2 supply-demand mismatch exhibit the largest hearts. The 'low O2 signal' stimulating postprandial cardiac hypertrophy is likely mediated by elevated ventricular wall stress associated with postprandial hemodynamics. © 2014. Published by The Company of Biologists Ltd.
Zuurbier, C J; Ince, C
2002-03-01
This study examined whether different durations of ischaemia (I) and reperfusion (R) altered the kinetics of O(2) consumption-to-demand matching and the contribution of changes in calcium and metabolic pathways to possible alterations. The response time of mitochondrial O(2) consumption (t(mito)) to a step in heart rate in isolated rat hearts was used as index for the response time of O(2) consumption-to-demand matching. At baseline, t(mito) was 8.9 +/- 0.4 s for all groups. At 5 min reperfusion, after both reversible (I=5 or I=15 min) or irreversible (I=25 min) ischaemia, matching was accelerated (t(mito) relative to baseline: 53 +/- 8%, 64 +/- 8%, 51+/- 6% and 100 +/- 5% for I=5, 15, 25 min and control). At late reperfusion (>30 min), reversible ischaemia resulted in a slowing of the matching, whereas after irreversible ischaemia t(mito) recovered to control values (156 +/- 16%, 153 +/- 13%, 92 +/- 7%, 114 +/- 6%, for I=5,15, 25 min and control, respectively). High perfusate Ca(2+) mimicked (t(mito): 44 +/- 11%), whereas blocking mitochondrial Ca(2+) uptake attenuated the acceleration observed at early reperfusion (t(mito): 7 +/- 5%). Replacing glucose with substrates used downstream of glycolysis (11 mM lactate or 11 mM pyruvate) abolished the reversible ischaemia-induced slowing of the matching at late reperfusion. It is concluded that I/R-induced changes in the kinetics of O(2) consumption-to demand matching depend critically on the duration of ischaemia and reperfusion. The data indicate that I/R-induced increases in Ca(2+) may, at least partly, explain the faster kinetics at early reperfusion, whereas I/R-induced increases in glycolysis from exogenous glucose result in slower matching of O(2) consumption-to-demand at late reperfusion.
Opportunities for Automated Demand Response in California Agricultural Irrigation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olsen, Daniel; Aghajanzadeh, Arian; McKane, Aimee
Pumping water for agricultural irrigation represents a significant share of California’s annual electricity use and peak demand. It also represents a large source of potential flexibility, as farms possess a form of storage in their wetted soil. By carefully modifying their irrigation schedules, growers can participate in demand response without adverse effects on their crops. This report describes the potential for participation in demand response and automated demand response by agricultural irrigators in California, as well as barriers to widespread participation. The report first describes the magnitude, timing, location, purpose, and manner of energy use in California. Typical on-farm controlsmore » are discussed, as well as common impediments to participation in demand response and automated demand response programs. Case studies of demand response programs in California and across the country are reviewed, and their results along with overall California demand estimates are used to estimate statewide demand response potential. Finally, recommendations are made for future research that can enhance the understanding of demand response potential in this industry.« less
Interpersonal interactions, job demands and work-related outcomes in pharmacy.
Gaither, Caroline A; Nadkarni, Anagha
2012-04-01
Objectives The objective of this study was to examine the interaction between job demands of pharmacists and resources in the form of interpersonal interactions and its association with work-related outcomes such as organizational and professional commitment, job burnout, professional identity and job satisfaction. The job demands-resources (JD-R) model served as the theoretical framework. Methods Subjects for the study were drawn from the Pharmacy Manpower Project Database (n = 1874). A 14-page mail-in survey measured hospital pharmacists' responses on the frequency of occurrence of various job-related scenarios as well as work-related outcomes. The study design was a 2 × 2 factorial design. Responses were collected on a Likert scale. Descriptive statistics, reliability analyses and correlational and multiple regression analyses were conducted using SPSS version 17 (SPSS, Chicago, IL, USA). Key findings The 566 pharmacists (30% response rate) who responded to the survey indicated that high-demand/pleasant encounters and low-demand/pleasant encounters occurred more frequently in the workplace. The strongest correlations were found between high-demand/unpleasant encounters and frequency and intensity of emotional exhaustion. Multiple regression analyses indicated that when controlling for demographic factors high-demand/unpleasant encounters were negatively related to affective organizational commitment and positively related to frequency and intensity of emotional exhaustion. Low-demand/pleasant encounters were positively related to frequency and intensity of personal accomplishment. Low-demand/unpleasant encounters were significantly and negatively related to professional commitment, job satisfaction and frequency and intensity of emotional exhaustion, while high-demand/pleasant encounters were also related to frequency and intensity of emotional exhaustion Conclusion Support was found for the JD-R model and the proposed interaction effects. Study results suggest that adequate attention must be paid to the interplay between demands on the job and interactions with healthcare professionals to improve the quality of the pharmacist's work life. Future research should examine other types of job demands and resources. © 2011 The Authors. IJPP © 2011 Royal Pharmaceutical Society.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piette, Mary Ann; Kiliccote, Sila; Ghatikar, Girish
2014-08-01
The need for and concepts behind demand response are evolving. As the electric system changes with more intermittent renewable electric supply systems, there is a need to allow buildings to provide more flexible demand. This paper presents results from field studies and pilots, as well as engineering estimates of the potential capabilities of fast load responsiveness in commercial buildings. We present a sector wide analysis of flexible loads in commercial buildings, which was conducted to improve resource planning and determine which loads to evaluate in future demonstrations. These systems provide important capabilities for future transactional systems. The field analysis ismore » based on results from California, plus projects in the northwest and east coast. End-uses considered include heating, ventilation, air conditioning and lighting. The timescales of control include day-ahead, as well as day-of, 10-minute ahead and even faster response. This technology can provide DR signals on different times scales to interact with responsive building loads. We describe the latency of the control systems in the building and the round trip communications with the wholesale grid operators.« less
Chassin, David P [Pasco, WA; Donnelly, Matthew K [Kennewick, WA; Dagle, Jeffery E [Richland, WA
2011-12-06
Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.
Chassin, David P.; Donnelly, Matthew K.; Dagle, Jeffery E.
2006-12-12
Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.
Mackillop, James; Murphy, Cara M.; Martin, Rosemarie A.; Stojek, Monika; Tidey, Jennifer W.; Colby, Suzanne M.
2016-01-01
Abstract Introduction: A cigarette purchase task (CPT) is a behavioral economic measure of the reinforcing value of smoking in monetary terms (ie, cigarette demand). This study investigated whether cigarette demand predicted response to contingent monetary rewards for abstinence among individuals with substance use disorders. It also sought to replicate evidence for greater price sensitivity at whole-dollar pack price transitions (ie, left-digit effects). Methods: Participants ( N = 338) were individuals in residential substance use disorder treatment who participated in a randomized controlled trial that compared contingent vouchers to noncontingent vouchers for smoking abstinence. Baseline demand indices were used to predict number of abstinent days during the 14-day voucher period (after the reduction lead-in) and at 1 and 3 months afterward. Results: Demand indices correlated with measures of smoking and nicotine dependence. As measured by elasticity, intensity and Omax , higher demand significantly predicted fewer abstinent exhaled carbon monoxide readings during voucher period for individuals in the noncontingent vouchers condition. Breakpoint exhibited a trend-level association with abstinent exhaled carbon monoxide readings. Demand indices did not predict abstinence in the contingent vouchers group, and did not predict abstinence at 1- and 3-month follow-ups. Left-digit price transitions were associated with significantly greater reductions in consumption. Conclusions: The association of cigarette demand with smoking behavior only in the group for whom abstinence was not incentivized indicates that CPT assesses the value of smoking more than the value of money per se and that vouchers counteract the effects of the intrinsic reinforcing value of cigarettes. Results provide initial short-term evidence of predictive validity for the CPT indices. Implications: This study provides the first evidence of the validity of the CPT for predicting early response to brief advice for smoking cessation plus nicotine replacement in smokers with substance dependence. However, demand for cigarettes did not predict voucher-based treatment response, indicating that incentives serve as a powerful motivator not to smoke that acts in opposition to the intrinsic reinforcing value of cigarettes and that the indices reflect the value of smoking more than the value of money per se. PMID:26498173
Careers in Water Pollution Control.
ERIC Educational Resources Information Center
Water Pollution Control Federation, Washington, DC.
Described are the activities, responsibilities, and educational and training requirements of the major occupations directly concerned with water pollution control. Also provided is an overview of employment trends, salaries, and projected demand for employees. Included in the appendix is a list of colleges and universities which offer…
Pilot Testing of Commercial Refrigeration-Based Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hirsch, Adam; Clark, Jordan; Deru, Michael
Supermarkets potentially offer a substantial demand response (DR) resource because of their high energy intensity and use patterns. This report describes a pilot project conducted to better estimate supermarket DR potential. Previous work has analyzed supermarket DR using heating, ventilating, and air conditioning (HVAC), lighting, and anti-condensate heaters. This project was concerned with evaluating DR using the refrigeration system and quantifying the DR potential inherent in supermarket refrigeration systems. Ancillary aims of the project were to identify practical barriers to the implementation of DR programs in supermarkets and to determine which high-level control strategies were most appropriate for achieving certainmore » DR objectives. The scope of this project does not include detailed control strategy development for DR or development of a strategy for regional implementation of DR in supermarkets.« less
NASA Astrophysics Data System (ADS)
Abdulaal, Ahmed
The work in this study addresses the current limitations of the price-driven demand response (DR) approach. Mainly, the dependability on consumers to respond in an energy aware conduct, the response timeliness, the difficulty of applying DR in a busy industrial environment, and the problem of load synchronization are of utmost concern. In order to conduct a simulation study, realistic price simulation model and consumers' building load models are created using real data. DR action is optimized using an autonomous control method, which eliminates the dependency on frequent consumer engagement. Since load scheduling and long-term planning approaches are infeasible in the industrial environment, the proposed method utilizes instantaneous DR in response to hour-ahead price signals (RTP-HA). Preliminary simulation results concluded savings at the consumer-side at the cost of increased supplier-side burden due to the aggregate effect of the universal DR policies. Therefore, a consumer disaggregation strategy is briefly discussed. Finally, a refined discrete-continuous control system is presented, which utilizes multi-objective Pareto optimization, evolutionary programming, utility functions, and bidirectional loads. Demonstrated through a virtual testbed fit with real data, the new system achieves momentary optimized DR in real-time while maximizing the consumer's wellbeing.
Effect of Response Reduction Factor on Peak Floor Acceleration Demand in Mid-Rise RC Buildings
NASA Astrophysics Data System (ADS)
Surana, Mitesh; Singh, Yogendra; Lang, Dominik H.
2017-06-01
Estimation of Peak Floor Acceleration (PFA) demand along the height of a building is crucial for the seismic safety of nonstructural components. The effect of the level of inelasticity, controlled by the response reduction factor (strength ratio), is studied using incremental dynamic analysis. A total of 1120 nonlinear dynamic analyses, using a suite of 30 recorded ground motion time histories, are performed on mid-rise reinforced-concrete (RC) moment-resisting frame buildings covering a wide range in terms of their periods of vibration. The obtained PFA demands are compared with some of the major national seismic design and retrofit codes (IS 1893 draft version, ASCE 41, EN 1998, and NZS 1170.4). It is observed that the PFA demand at the building's roof level decreases with increasing period of vibration as well as with strength ratio. However, current seismic building codes do not account for these effects thereby producing very conservative estimates of PFA demands. Based on the identified parameters affecting the PFA demand, a model to obtain the PFA distribution along the height of a building is proposed. The proposed model is validated with spectrum-compatible time history analyses of the considered buildings with different strength ratios.
Acute stress shifts the balance between controlled and automatic processes in prospective memory.
Möschl, Marcus; Walser, Moritz; Plessow, Franziska; Goschke, Thomas; Fischer, Rico
2017-10-01
In everyday life we frequently rely on our abilities to postpone intentions until later occasions (prospective memory; PM) and to deactivate completed intentions even in stressful situations. Yet, little is known about the effects of acute stress on these abilities. In the present work we investigated the impact of acute stress on PM functioning under high task demands. (1) Different from previous studies, in which intention deactivation required mostly low processing demands, we used salient focal PM cues to induce high processing demands during intention-deactivation phases. (2) We systematically manipulated PM-monitoring demands in a nonfocal PM task that required participants to monitor for either one or six specific syllables that could occur in ongoing-task words. Eighty participants underwent the Trier Social Stress Test, a standardized stress induction protocol, or a standardized control situation, before performing a computerized PM task. Our primary interests were whether PM performance, PM-monitoring costs, aftereffects of completed intentions and/or commission-error risk would differ between stressed and non-stressed individuals and whether these effects would differ under varying task demands. Results revealed that PM performance and aftereffects of completed intentions during subsequent performance were not affected by acute stress induction, replicating previous findings. Under high demands on intention deactivation (focal condition), however, acute stress produced a nominal increase in erroneous PM responses after intention completion (commission errors). Most importantly, under high demands on PM monitoring (nonfocal condition), acute stress led to a substantial reduction in PM-monitoring costs. These findings support ideas of selective and demand-dependent effects of acute stress on cognitive functioning. Under high task demands, acute stress might induce a shift in processing strategy towards resource-saving behavior, which seems to increase the efficiency of PM performance (reduced monitoring costs), but might increase initial susceptibility to automatic response activation after intention completion. Copyright © 2017 Elsevier Inc. All rights reserved.
Badre, David; Wagner, Anthony D
2004-02-05
Prefrontal cortex (PFC) supports flexible behavior by mediating cognitive control, though the elemental forms of control supported by PFC remain a central debate. Dorsolateral PFC (DLPFC) is thought to guide response selection under conditions of response conflict or, alternatively, may refresh recently active representations within working memory. Lateral frontopolar cortex (FPC) may also adjudicate response conflict, though others propose that FPC supports higher order control processes such as subgoaling and integration. Anterior cingulate cortex (ACC) is hypothesized to upregulate response selection by detecting response conflict; it remains unclear whether ACC functions generalize beyond monitoring response conflict. The present fMRI experiment directly tested these competing theories regarding the functional roles of DLPFC, FPC, and ACC. Results reveal dissociable control processes in PFC, with mid-DLPFC selectively mediating resolution of response conflict and FPC further mediating subgoaling/integration. ACC demonstrated a broad sensitivity to control demands, suggesting a generalized role in modulating cognitive control.
Energy Efficiency and Demand Response for Residential Applications
NASA Astrophysics Data System (ADS)
Wellons, Christopher J., II
The purpose of this thesis is to analyze the costs, feasibility and benefits of implementing energy efficient devices and demand response programs to a residential consumer environment. Energy efficiency and demand response are important for many reasons, including grid stabilization. With energy demand increasing, as the years' pass, the drain on the grid is going up. There are two key solutions to this problem, increasing supply by building more power plants and decreasing demand during peak periods, by increasing participation in demand response programs and by upgrading residential and commercial customers to energy efficient devices, to lower demand throughout the day. This thesis focuses on utilizing demand response methods and energy efficient device to reduce demand. Four simulations were created to analyze these methods. These simulations show the importance of energy efficiency and demand response participation to help stabilize the grid, integrate more alternative energy resources, and reduce emissions from fossil fuel generating facilities. The results of these numerical analyses show that demand response and energy efficiency can be beneficial to consumers and utilities. With demand response being the most beneficial to the utility and energy efficiency, specifically LED lighting, providing the most benefits to the consumer.
Characteristics of an electro-rheological fluid valve used in an inkjet printhead
NASA Astrophysics Data System (ADS)
Lee, C. Y.; Liao, W. C.
2000-12-01
The demand for non-impact printers has grown considerably with the advent of personal computers. For entry-level mass production, two drop-on-demand techniques have dominated the market - piezoelectric impulse and thermal-bubble types. However, the high cost of the piezoelectric printhead and the thermal problems encountered by the thermal-bubble jet printhead have restrained the use of these techniques in an array-type printhead. In this study, we propose a new design of printhead with an electro-rheological (ER) fluid acting as a control medium. The ER fluid valve controls the ink ejection. As a first step toward developing this new printhead, the characteristics of an ER fluid valve which controls the deflection of the elastic diaphragm are investigated. First, the response of a prototype is tested experimentally to prove the feasibility of using this ER valve for the inkjet printhead. Then, the discretized governing equation of the ER valve is derived. Finally, the prototype of the ER valve is fabricated. The experimental measurement based on the sinusoidal response verifies both the theoretical analysis and the controllability of the response of the ER valve by the applied electric field.
Lindheimer, Jacob B; OʼConnor, Patrick J; McCully, Kevin K; Dishman, Rod K
Prior attempts to measure psychological responses to exercise are potentially limited by a failure to account for participants' expectations, the absence of a valid exercise placebo, and demand characteristics. The purpose of this study was to explore the main and interactive effects of a manipulation designed to increase expectations about the psychological benefits of an acute bout of active, light-intensity (treatment), and passive (placebo) cycling on mood and cognition. Demand characteristics were attenuated during recruitment, informed consent, and interactions with test administrators by communicating to participants that the study purpose was to assess the effects of active and passive cycling on respiration, heart rate, and muscle activation. A repeated-measures, randomized, placebo-controlled design (n = 60) was used with cycling (active, passive) and information (informed, not informed) as between-subjects factors. State anxiety, feelings of energy, and working memory (percent accuracy and reaction time for correct responses) were measured at baseline (time 1), immediately after cycling (time 2) and 20 minutes after cycling (time 3). Most participants did not guess the purpose of the study (~92%) or expect a reduction in state anxiety (85%) or an increase in energy (80%) or cognitive performance (~93%). Mood and cognitive performance were not improved by active or passive cycling (all p values ≥ .12). The methods used here to disguise the experimental hypotheses provide a potential framework for reducing demand characteristics and placebo responses in future investigations of psychological responses to exercise.
Controller for thermostatically controlled loads
Lu, Ning; Zhang, Yu; Du, Pengwei; Makarov, Yuri V.
2016-06-07
A system and method of controlling aggregated thermostatically controlled appliances (TCAs) for demand response is disclosed. A targeted load profile is formulated and a forecasted load profile is generated. The TCAs within an "on" or "off" control group are prioritized based on their operating temperatures. The "on" or "off" status of the TCAs is determined. Command signals are sent to turn on or turn off the TCAs.
Ad libitum or demand/semi-demand feeding versus scheduled interval feeding for preterm infants.
McCormick, Felicia M; Tosh, Karen; McGuire, William
2010-02-17
Scheduled interval feeding of prescribed enteral volumes is current standard practice for preterm infants. However, feeding preterm infants in response to their hunger and satiation cues (ad libitum or demand/semi demand) rather than at scheduled intervals might help in the establishment of independent oral feeding, increase nutrient intake and growth rates, and allow earlier hospital discharge. To assess the effect of a policy of feeding preterm infants on an ad libitum or demand/semi-demand basis versus feeding prescribed volumes at scheduled intervals on growth rates and the time to hospital discharge. We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2009), MEDLINE (1966 to Oct 2009), EMBASE (1980 to Oct 2009), CINAHL (1982 to Oct 2009), conference proceedings, and previous reviews. Randomised or quasi-randomised controlled trials (including cluster randomised trials) that compared a policy of feeding preterm infants on an ad libitum or demand/semi-demand basis versus feeding at scheduled intervals. We used the standard methods of the Cochrane Neonatal Review Group with separate evaluation of trial quality and data extraction by two review authors. We found eight randomised controlled trials that compared ad libitum or demand/semi-demand regimens with scheduled interval regimes in preterm infants in the transition phase from intragastric tube to oral feeding. The trials were generally small and of variable methodological quality. The duration of the intervention and the duration of data collection and follow-up in most of the trials was not likely to have allowed detection of measurable effects on growth. Three trials reported that feeding preterm infants using an ad libitum or demand/semi-demand feeding regimen allowed earlier discharge from hospital (by about two to four days) but other trials did not confirm this finding. Limited evidence exists that feeding preterm infants with ad libitum or demand/semi-demand regimens allows earlier attainment of full oral feeding and earlier hospital discharge. This finding should be interpreted cautiously because of methodological weaknesses in the included trials. A large randomised controlled trial is needed to confirm this finding and to determine if ad libitum of demand/semi-demand feeding of preterm infants affects other clinically important outcomes.
Schmidt, Klaus-Helmut; Diestel, Stefan
2011-03-01
According to the influential Job Demands-Control (JD-C) model developed by Karasek (1979; Karasek and Theorell, 1990), job strain is expected to result from high job demands and low job control as well as an interaction between both job characteristics. Previous research, however, has found such an interaction only rarely or inconsistently.It has been suggested that the conceptualization of the control variable (formerly referred to as decision latitude) may be particularly responsible for the lack of supportive findings. The present study aimed at clarifying this issue by contrasting a focused measure of control with a traditional measure of decision latitude in their relations to job strain of health care workers. The measure of decision latitude encompassed a wide range of job characteristics including control, task variety, and learning opportunities. A cross-sectional questionnaire survey was conducted with job satisfaction, psychosomatic complaints and emotional exhaustion as criterion measures of job strain. A supra-regional organization for residential elderly care with 11 nursing homes located in a federal state in Germany. Questionnaires were distributed to the whole nursing staff, of which 379 filled in the questionnaire during normal working hours (68% participation rate). In addition to confirmatory factor analyses, descriptive statistics, and bivariate correlations, hierarchical multiple regression analyses were performed for testing the corresponding interaction effects. Findings confirmed the assumption that the focused measure of control and the traditional measure of decision latitude represent distinct, yet correlated factors. Furthermore, findings revealed a significant interaction effect between job demands and control on all outcomes considered. By way of contrast, there was no equivalent interaction effect between job demands and decision latitude. In line with the JD-C model, the adverse influence of increasing demands on job satisfaction, psychosomatic complaints and emotional exhaustion were reduced with increasing job control. Extending the opportunities of health care workers to control work scheduling and the way of performing given tasks can make them less vulnerable against the adverse effects of high job demands. Copyright © 2010 Elsevier Ltd. All rights reserved.
Wesley, Michael J; Lile, Joshua A; Fillmore, Mark T; Porrino, Linda J
2017-06-01
Determining the neurobehavioral profiles that differentiate heavy drinkers who are and are not alcohol dependent will inform treatment efforts. Working memory is linked to substance use disorders and can serve as a representation of the demand placed on the neurophysiology associated with cognitive control. Behavior and brain activity (via fMRI) were recorded during an N-Back working memory task in controls (CTRL), nondependent heavy drinkers (A-ND) and dependent heavy drinkers (A-D). Typical and novel step-wise analyses examined profiles of working memory load and increasing task demand, respectively. Performance was significantly decreased in A-D during high working memory load (2-Back), compared to CTRL and A-ND. Analysis of brain activity during high load (0-Back vs. 2- Back) showed greater responses in the dorsal lateral and medial prefrontal cortices of A-D than CTRL, suggesting increased but failed compensation. The step-wise analysis revealed that the transition to Low Demand (0-Back to 1-Back) was associated with robust increases and decreases in cognitive control and default-mode brain regions, respectively, in A-D and A-ND but not CTRL. The transition to High Demand (1-Back to 2-Back) resulted in additional engagement of these networks in A-ND and CTRL, but not A-D. Heavy drinkers engaged working memory neural networks at lower demand than controls. As demand increased, nondependent heavy drinkers maintained control performance but relied on additional neurophysiological resources, and dependent heavy drinkers did not display further resource engagement and had poorer performance. These results support targeting these brain areas for treatment interventions. Copyright © 2017 Elsevier B.V. All rights reserved.
A Method for Exploiting Redundancy to Accommodate Actuator Limits in Multivariable Systems
NASA Technical Reports Server (NTRS)
Litt, Jonathan; Roulette, Greg
1995-01-01
This paper introduces a new method for accommodating actuator saturation in a multivariable system with actuator redundancy. Actuator saturation can cause significant deterioration in control system performance because unmet demand may result in sluggish transients and oscillations in response to setpoint changes. To help compensate for this problem, a technique has been developed which takes advantage of redundancy in multivariable systems to redistribute the unmet control demand over the remaining useful effectors. This method is not a redesign procedure, rather it modifies commands to the unlimited effectors to compensate for those which are limited, thereby exploiting the built-in redundancy. The original commands are modified by the increments due to unmet demand, but when a saturated effector comes off its limit, the incremental commands disappear and the original unmodified controller remains intact. This scheme provides a smooth transition between saturated and unsaturated modes as it divides up the unmet requirement over any available actuators. This way, if there is sufficiently redundant control authority, performance can be maintained.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hudgins, Andrew P.; Carrillo, Ismael M.; Jin, Xin
This document is the final report of a two-year development, test, and demonstration project, 'Cohesive Application of Standards- Based Connected Devices to Enable Clean Energy Technologies.' The project was part of the National Renewable Energy Laboratory's (NREL's) Integrated Network Testbed for Energy Grid Research and Technology (INTEGRATE) initiative hosted at Energy Systems Integration Facility (ESIF). This project demonstrated techniques to control distribution grid events using the coordination of traditional distribution grid devices and high-penetration renewable resources and demand response. Using standard communication protocols and semantic standards, the project examined the use cases of high/low distribution voltage, requests for volt-ampere-reactive (VAR)more » power support, and transactive energy strategies using Volttron. Open source software, written by EPRI to control distributed energy resources (DER) and demand response (DR), was used by an advanced distribution management system (ADMS) to abstract the resources reporting to a collection of capabilities rather than needing to know specific resource types. This architecture allows for scaling both horizontally and vertically. Several new technologies were developed and tested. Messages from the ADMS based on the common information model (CIM) were developed to control the DER and DR management systems. The OpenADR standard was used to help manage grid events by turning loads off and on. Volttron technology was used to simulate a homeowner choosing the price at which to enter the demand response market. Finally, the ADMS used newly developed algorithms to coordinate these resources with a capacitor bank and voltage regulator to respond to grid events.« less
Shannon, R.H.; Williamson, H.E.
1962-10-30
A boiling water type nuclear reactor power system having improved means of control is described. These means include provisions for either heating the coolant-moderator prior to entry into the reactor or shunting the coolantmoderator around the heating means in response to the demand from the heat engine. These provisions are in addition to means for withdrawing the control rods from the reactor. (AEC)
Taxonomy for Modeling Demand Response Resources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olsen, Daniel; Kiliccote, Sila; Sohn, Michael
2014-08-01
Demand response resources are an important component of modern grid management strategies. Accurate characterizations of DR resources are needed to develop systems of optimally managed grid operations and to plan future investments in generation, transmission, and distribution. The DOE Demand Response and Energy Storage Integration Study (DRESIS) project researched the degree to which demand response (DR) and energy storage can provide grid flexibility and stability in the Western Interconnection. In this work, DR resources were integrated with traditional generators in grid forecasting tools, specifically a production cost model of the Western Interconnection. As part of this study, LBNL developed amore » modeling framework for characterizing resource availability and response attributes of DR resources consistent with the governing architecture of the simulation modeling platform. In this report, we identify and describe the following response attributes required to accurately characterize DR resources: allowable response frequency, maximum response duration, minimum time needed to achieve load changes, necessary pre- or re-charging of integrated energy storage, costs of enablement, magnitude of controlled resources, and alignment of availability. We describe a framework for modeling these response attributes, and apply this framework to characterize 13 DR resources including residential, commercial, and industrial end-uses. We group these end-uses into three broad categories based on their response capabilities, and define a taxonomy for classifying DR resources within these categories. The three categories of resources exhibit different capabilities and differ in value to the grid. Results from the production cost model of the Western Interconnection illustrate that minor differences in resource attributes can have significant impact on grid utilization of DR resources. The implications of these findings will be explored in future DR valuation studies.« less
Stock, Ann-Kathrin; Steenbergen, Laura; Colzato, Lorenza; Beste, Christian
2016-12-01
Cognitive control is adaptive in the sense that it inhibits automatic processes to optimize goal-directed behavior, but high levels of control may also have detrimental effects in case they suppress beneficial automatisms. Until now, the system neurophysiological mechanisms and functional neuroanatomy underlying these adverse effects of cognitive control have remained elusive. This question was examined by analyzing the automatic exploitation of a beneficial implicit predictive feature under conditions of high versus low cognitive control demands, combining event-related potentials (ERPs) and source localization. It was found that cognitive control prohibits the beneficial automatic exploitation of additional implicit information when task demands are high. Bottom-up perceptual and attentional selection processes (P1 and N1 ERPs) are not modulated by this, but the automatic exploitation of beneficial predictive information in case of low cognitive control demands was associated with larger response-locked P3 amplitudes and stronger activation of the right inferior frontal gyrus (rIFG, BA47). This suggests that the rIFG plays a key role in the detection of relevant task cues, the exploitation of alternative task sets, and the automatic (bottom-up) implementation and reprogramming of action plans. Moreover, N450 amplitudes were larger under high cognitive control demands, which was associated with activity differences in the right medial frontal gyrus (BA9). This most likely reflects a stronger exploitation of explicit task sets which hinders the exploration of the implicit beneficial information in case of high cognitive control demands. Hum Brain Mapp 37:4511-4522, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Johannessen, Håkon A; Tynes, Tore; Sterud, Tom
2013-06-01
To examine the impact of occupational role conflict and emotional demands on subsequent psychological distress. A randomly drawn cohort from the general Norwegian working-age population was followed up for 3 years (n = 12,550; response rate = 67%). Eligible respondents were in paid work during the reference week in 2006 and 2009 or temporarily absent from such work (n = 6,745; response rate = 68%). In the fully adjusted model, both high role conflict (odds ratios = 1.53; 95% CI = 1.15 to 2.03) and high emotional demands (odds ratios = 1.38; 95% CI = 1.13 to 1.69) were significant predictors of psychological distress. Additional significant predictors were low job control, bullying/harassment, and job insecurity (P < 0.05). Considering all of the evaluated work-related factors, role conflict and emotional demands contributed the most to the population risk of developing psychological distress.
NASA Astrophysics Data System (ADS)
Rajagopalan, K.; Chinnayakanahalli, K. J.; Stockle, C. O.; Nelson, R. L.; Kruger, C. E.; Brady, M. P.; Malek, K.; Dinesh, S. T.; Barber, M. E.; Hamlet, A. F.; Yorgey, G. G.; Adam, J. C.
2018-03-01
Adaptation to a changing climate is critical to address future global food and water security challenges. While these challenges are global, successful adaptation strategies are often generated at regional scales; therefore, regional-scale studies are critical to inform adaptation decision making. While climate change affects both water supply and demand, water demand is relatively understudied, especially at regional scales. The goal of this work is to address this gap, and characterize the direct impacts of near-term (for the 2030s) climate change and elevated CO2 levels on regional-scale crop yields and irrigation demands for the Columbia River basin (CRB). This question is addressed through a coupled crop-hydrology model that accounts for site-specific and crop-specific characteristics that control regional-scale response to climate change. The overall near-term outlook for agricultural production in the CRB is largely positive, with yield increases for most crops and small overall increases in irrigation demand. However, there are crop-specific and location-specific negative impacts as well, and the aggregate regional response of irrigation demands to climate change is highly sensitive to the spatial crop mix. Low-value pasture/hay varieties of crops—typically not considered in climate change assessments—play a significant role in determining the regional response of irrigation demands to climate change, and thus cannot be overlooked. While, the overall near-term outlook for agriculture in the region is largely positive, there may be potential for a negative outlook further into the future, and it is important to consider this in long-term planning.
Cognitive Control Reflects Context Monitoring, Not Motoric Stopping, in Response Inhibition
Chatham, Christopher H.; Claus, Eric D.; Kim, Albert; Curran, Tim; Banich, Marie T.; Munakata, Yuko
2012-01-01
The inhibition of unwanted behaviors is considered an effortful and controlled ability. However, inhibition also requires the detection of contexts indicating that old behaviors may be inappropriate – in other words, inhibition requires the ability to monitor context in the service of goals, which we refer to as context-monitoring. Using behavioral, neuroimaging, electrophysiological and computational approaches, we tested whether motoric stopping per se is the cognitively-controlled process supporting response inhibition, or whether context-monitoring may fill this role. Our results demonstrate that inhibition does not require control mechanisms beyond those involved in context-monitoring, and that such control mechanisms are the same regardless of stopping demands. These results challenge dominant accounts of inhibitory control, which posit that motoric stopping is the cognitively-controlled process of response inhibition, and clarify emerging debates on the frontal substrates of response inhibition by replacing the centrality of controlled mechanisms for motoric stopping with context-monitoring. PMID:22384038
Liu, Guo-Tian; Xu, Hong-Guo; Wang, Li-Jun; Li, Shao-Hua
2013-01-01
Background The decline of photosynthesis in plants under low sink demand is well known. Previous studies focused on the relationship between stomatal conductance (g s) and net photosynthetic rate (P n). These studies investigated the effect of changes in Photosystem II (PSII) function on the P n decline under low sink demand. However, little is known about its effects on different limiting steps of electron transport chain in PSII under this condition. Methodology/Principal Finding Two-month-old bean plants were processed by removing pods and flowers (low sink demand). On the 1st day after low sink demand treatment, a decline of P n was accompanied by a decrease in g s and internal-to-ambient CO2 concentration ratio (C i/C a). From the 3rd to 9th day, P n and g s declined continuously while C i/C a ratio remained stable in the treatment. Moreover, these values were lower than that of control. Wk (a parameter reflecting the damage to oxygen evolving complex of the donor side of PSII) values in the treatment were significantly higher than their corresponding control values. However, RCQA (a parameter reflecting the number of active RCs per excited cross-section of PSII) values in the treatment were significantly lower than control from the 5th day. From the 11th to 21st day, P n and g s of the treatment continued to decline and were lower than control. This was accompanied by a decrease of RCQA, and an increase of Wk. Furthermore, the quantum yield parameters φ Po, φ Eo and ψ Eo in the treatment were lower than in control; however, C i/C a values in the treatment gradually increased and were significantly higher than control on the 21st day. Conclusions Stomatal limitation during the early stage, whereas a combination of stomatal and non-stomatal limitation during the middle stage might be responsible for the reduction of P n under low sink demand. Non-stomatal limitation during the late stages after the removal of the sink of roots and pods may also cause P n reduction. The non-stomatal limitation was associated with the inhibition of PSII electron transport chain. Our data suggests that the donor side of PSII was the most sensitive to low sink demand followed by the reaction center of PSII. The acceptor side of PSII may be the least sensitive. PMID:24324626
NASA Astrophysics Data System (ADS)
Pourmousavi Kani, Seyyed Ali
Future power systems (known as smart grid) will experience a high penetration level of variable distributed energy resources to bring abundant, affordable, clean, efficient, and reliable electric power to all consumers. However, it might suffer from the uncertain and variable nature of these generations in terms of reliability and especially providing required balancing reserves. In the current power system structure, balancing reserves (provided by spinning and non-spinning power generation units) usually are provided by conventional fossil-fueled power plants. However, such power plants are not the favorite option for the smart grid because of their low efficiency, high amount of emissions, and expensive capital investments on transmission and distribution facilities, to name a few. Providing regulation services in the presence of variable distributed energy resources would be even more difficult for islanded microgrids. The impact and effectiveness of demand response are still not clear at the distribution and transmission levels. In other words, there is no solid research reported in the literature on the evaluation of the impact of DR on power system dynamic performance. In order to address these issues, a real-time demand response approach along with real-time power management (specifically for microgrids) is proposed in this research. The real-time demand response solution is utilized at the transmission (through load-frequency control model) and distribution level (both in the islanded and grid-tied modes) to provide effective and fast regulation services for the stable operation of the power system. Then, multiple real-time power management algorithms for grid-tied and islanded microgrids are proposed to economically and effectively operate microgrids. Extensive dynamic modeling of generation, storage, and load as well as different controller design are considered and developed throughout this research to provide appropriate models and simulation environment to evaluate the effectiveness of the proposed methodologies. Simulation results revealed the effectiveness of the proposed methods in providing balancing reserves and microgrids' economic and stable operation. The proposed tools and approaches can significantly enhance the application of microgrids and demand response in the smart grid era. They will also help to increase the penetration level of variable distributed generation resources in the smart grid.
Upper Limb Absence: Predictors of Work Participation and Work Productivity.
Postema, Sietke G; Bongers, Raoul M; Brouwers, Michael A; Burger, Helena; Norling-Hermansson, Liselotte M; Reneman, Michiel F; Dijkstra, Pieter U; van der Sluis, Corry K
2016-06-01
To analyze work participation, work productivity, contributing factors, and physical work demands of individuals with upper limb absence (ULA). Cross-sectional study: postal survey (response rate, 45%). Twelve rehabilitation centers and orthopedic workshops. Individuals (n=207) with unilateral transverse upper limb reduction deficiency (RD) or acquired amputation (AA), at or proximal to the carpal level, between the ages of 18 and 65 years, and a convenience sample of control subjects (n=90) matched on age and sex. Not applicable. Employment status, self-reported work productivity measured with the Quality-Quantity method, and self-reported upper extremity work demands measured with the Upper Extremity Work Demands scale. Seventy-four percent of the individuals with RD and 57% of the individuals with AA were employed (vs 82% of the control group and 66% of the general population). Male sex, younger age, a medium or higher level of education, prosthesis use, and good general health were predictors of work participation. Work productivity was similar to that of the control group. Higher work productivity was inversely related to musculoskeletal complaint-related pain. When having predominantly mentally demanding work, individuals with ULA perceived higher upper extremity work demands compared with controls. Work participation of individuals with RD was slightly higher compared with that of the general population, whereas employment rates of individuals with AA were slightly lower. Furthermore, work productivity did not differ between individuals with RD, AA, and controls. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Day, Arla; Paquet, Stephanie; Scott, Natasha; Hambley, Laura
2012-10-01
Although many employees are using more information communication technology (ICT) as part of their jobs, few studies have examined the impact of ICT on their well-being, and there is a lack of validated measures designed to assess the ICT factors that may impact employee well-being. Therefore, we developed and validated a measure of ICT demands and supports. Using Exploratory Structural Equation Modeling, we found support for 8 ICT demands (i.e., availability, communication, ICT control, ICT hassles, employee monitoring, learning, response expectations, and workload) and two facets of ICT support (personal assistance and resources/upgrades support). Jointly, the ICT demands were associated with increased strain, stress, and burnout and were still associated with stress and strain after controlling for demographics, job variables, and job demands. The two types of ICT support were associated with lower stress, strain, and burnout. Resources/upgrades support moderated the relationship between learning expectations and most strain outcomes and between ICT hassles and strain. Personal assistance support moderated the relationship between ICT hassles and strain.
Dynamic management of integrated residential energy systems
NASA Astrophysics Data System (ADS)
Muratori, Matteo
This study combines principles of energy systems engineering and statistics to develop integrated models of residential energy use in the United States, to include residential recharging of electric vehicles. These models can be used by government, policymakers, and the utility industry to provide answers and guidance regarding the future of the U.S. energy system. Currently, electric power generation must match the total demand at each instant, following seasonal patterns and instantaneous fluctuations. Thus, one of the biggest drivers of costs and capacity requirement is the electricity demand that occurs during peak periods. These peak periods require utility companies to maintain operational capacity that often is underutilized, outdated, expensive, and inefficient. In light of this, flattening the demand curve has long been recognized as an effective way of cutting the cost of producing electricity and increasing overall efficiency. The problem is exacerbated by expected widespread adoption of non-dispatchable renewable power generation. The intermittent nature of renewable resources and their non-dispatchability substantially limit the ability of electric power generation of adapting to the fluctuating demand. Smart grid technologies and demand response programs are proposed as a technical solution to make the electric power demand more flexible and able to adapt to power generation. Residential demand response programs offer different incentives and benefits to consumers in response to their flexibility in the timing of their electricity consumption. Understanding interactions between new and existing energy technologies, and policy impacts therein, is key to driving sustainable energy use and economic growth. Comprehensive and accurate models of the next-generation power system allow for understanding the effects of new energy technologies on the power system infrastructure, and can be used to guide policy, technology, and economic decisions. This dissertation presents a bottom-up highly resolved model of a generic residential energy eco-system in the United States. The model is able to capture the entire energy footprint of an individual household, to include all appliances, space conditioning systems, in-home charging of plug-in electric vehicles, and any other energy needs, viewing residential and transportation energy needs as an integrated continuum. The residential energy eco-system model is based on a novel bottom-up approach that quantifies consumer energy use behavior. The incorporation of stochastic consumer behaviors allows capturing the electricity consumption of each residential specific end-use, providing an accurate estimation of the actual amount of available controllable resources, and for a better understanding of the potential of residential demand response programs. A dynamic energy management framework is then proposed to manage electricity consumption inside each residential energy eco-system. Objective of the dynamic energy management framework is to optimize the scheduling of all the controllable appliances and in-home charging of plug-in electric vehicles to minimize cost. Such an automated energy management framework is used to simulate residential demand response programs, and evaluate their impact on the electric power infrastructure. For instance, time-varying electricity pricing might lead to synchronization of the individual residential demands, creating pronounced rebound peaks in the aggregate demand that are higher and steeper than the original demand peaks that the time-varying electricity pricing structure intended to eliminate. The modeling tools developed in this study can serve as a virtual laboratory for investigating fundamental economic and policy-related questions regarding the interplay of individual consumers with energy use. The models developed allow for evaluating the impact of different energy policies, technology adoption, and electricity price structures on the total residential electricity demand. In particular, two case studies are reported in this dissertation to illustrate application of the tools developed. The first considers the impact of market penetration of plug-in electric vehicles on the electric power infrastructure. The second provides a quantitative comparison of the impact of different electricity price structures on residential demand response. Simulation results and an electricity price structure, called Multi-TOU, aimed at solving the rebound peak issue, are presented.
Stressful working conditions and poor self-rated health among financial services employees.
Silva, Luiz Sérgio; Barreto, Sandhi Maria
2012-06-01
To assess the association between exposure to adverse psychosocial working conditions and poor self-rated health among bank employees. A cross-sectional study including a sample of 2,054 employees of a government bank was conducted in 2008. Self-rated health was assessed by a single question: "In general, would you say your health is (...)." Exposure to adverse psychosocial working conditions was evaluated by the effort-reward imbalance model and the demand-control model. Information on other independent variables was obtained through a self-administered semi-structured questionnaire. A multiple logistic regression analysis was performed and odds ratio calculated to assess independent associations between adverse psychosocial working conditions and poor self-rated health. The overall prevalence of poor self-rated health was 9%, with no significant gender difference. Exposure to high demand and low control environment at work was associated with poor self-rated health. Employees with high effort-reward imbalance and overcommitment also reported poor self-rated health, with a dose-response relationship. Social support at work was inversely related to poor self-rated health, with a dose-response relationship. Exposure to adverse psychosocial work factors assessed based on the effort-reward imbalance model and the demand-control model is independently associated with poor self-rated health among the workers studied.
Firing Costs and Flexibility: Evidence from Firms’ Employment Responses to Shocks in India*
Adhvaryu, Achyuta; Chari, A. V.; Sharma, Siddharth
2013-01-01
A key prediction of dynamic labor demand models is that firing restrictions attenuate firms’ employment responses to economic fluctuations. We provide the first direct test of this prediction using data from India. We exploit the fact that rainfall fluctuations, through their effects on agricultural productivity, generate variation in local demand within districts over time. Consistent with the theory, we find that industrial employment is more sensitive to shocks where labor regulation is less restrictive. Our results are robust to controlling for endogenous firm placement and vary across factory size in a pattern consistent with institutional features of Indian labor law. PMID:24357882
Inhibitory Processes in Young Children and Individual Variation in Short-Term Memory
Espy, Kimberly Andrews; Bull, Rebecca
2009-01-01
A precise definition of executive control remains elusive, related in part to the variations among executive tasks in the nature of the task demands, which complicate the identification of test-specific versus construct-specific performance. In this study, tasks were chosen that varied in the nature of the stimulus (verbal, nonverbal), response (naming, somatic motor), conflict type (proactive interference, distraction), and inhibitory process (attention control, response suppression) required. Then performance differences were examined in 184 young children (age range = 3 years 6 months to 6 years 1 month), comparing those with high (5 or more digits) and low (3 or fewer digits) spans to determine the dependence on short-term memory. Results indicated that there was communality in inhibitory task demands across instruments, although the specific pattern of task intercorrelations varied in children with high and low spans. Furthermore, only performance on attention control tasks—that is, that require cognitive engagement/disengagement among an internally represented rule or response set that was previously active versus those currently active—differed between children of high and low spans. In contrast, there were differences neither between children with high and low spans on response suppression tasks nor on tasks when considered by type of stimulus, response, or conflict. Individual differences in well-regulated thought may rest in variations in the ability to maintain information in an active, quickly retrievable state that subserve controlling attention in a goal-relevant fashion. PMID:16144432
Chiu, Yu-Chin; Egner, Tobias
2015-08-26
Response inhibition is a key component of executive control, but its relation to other cognitive processes is not well understood. We recently documented the "inhibition-induced forgetting effect": no-go cues are remembered more poorly than go cues. We attributed this effect to central-resource competition, whereby response inhibition saps attention away from memory encoding. However, this proposal is difficult to test with behavioral means alone. We therefore used fMRI in humans to test two neural predictions of the "common resource hypothesis": (1) brain regions associated with response inhibition should exhibit greater resource demands during encoding of subsequently forgotten than remembered no-go cues; and (2) this higher inhibitory resource demand should lead to memory encoding regions having less resources available during encoding of subsequently forgotten no-go cues. Participants categorized face stimuli by gender in a go/no-go task and, following a delay, performed a surprise recognition memory test for those faces. Replicating previous findings, memory was worse for no-go than for go stimuli. Crucially, forgetting of no-go cues was predicted by high inhibitory resource demand, as quantified by the trial-by-trial ratio of activity in neural "no-go" versus "go" networks. Moreover, this index of inhibitory demand exhibited an inverse trial-by-trial relationship with activity in brain regions responsible for the encoding of no-go cues into memory, notably the ventrolateral prefrontal cortex. This seesaw pattern between the neural resource demand of response inhibition and activity related to memory encoding directly supports the hypothesis that response inhibition temporarily saps attentional resources away from stimulus processing. Recent behavioral experiments showed that inhibiting a motor response to a stimulus (a "no-go cue") impairs subsequent memory for that cue. Here, we used fMRI to test whether this "inhibition-induced forgetting effect" is caused by competition for neural resources between the processes of response inhibition and memory encoding. We found that trial-by-trial variations in neural inhibitory resource demand predicted subsequent forgetting of no-go cues and that higher inhibitory demand was furthermore associated with lower concurrent activation in brain regions responsible for successful memory encoding of no-go cues. Thus, motor inhibition and stimulus encoding appear to compete with each other: when more resources have to be devoted to inhibiting action, less are available for encoding sensory stimuli. Copyright © 2015 the authors 0270-6474/15/3511936-10$15.00/0.
ERIC Educational Resources Information Center
Law, Sui-Heung; Lo, Sing Kai; Chow, Susanna; Cheing, Gladys L.Y.
2011-01-01
Excessive grip force (GF) is often found in children with developmental coordination disorder (DCD). However, their GF control may vary when task constraints are imposed upon their motor performance. This study aimed to investigate how their GF control changes in response to task demands, and to examine their tactile sensitivity. Twenty-one…
The Environmental Assessment and Management (TEAM) Guide: Idaho Supplement
2010-02-01
rsons u nder common control ). Pollutant-emitting activities shall be considered as part of the same industrial grouping if they belong to the same...area ASTM American Society for Testing and Materials AWWA American Water Works Association BACT best available control technology BOD...biochemical oxygen demand BTEX benzene, toluene, elthylbenzene, xylene CAR control area responsible party CAS Chemical Abstract Service CEM continuous
A Study of Energy Management Systems and its Failure Modes in Smart Grid Power Distribution
NASA Astrophysics Data System (ADS)
Musani, Aatif
The subject of this thesis is distribution level load management using a pricing signal in a smart grid infrastructure. The project relates to energy management in a spe-cialized distribution system known as the Future Renewable Electric Energy Delivery and Management (FREEDM) system. Energy management through demand response is one of the key applications of smart grid. Demand response today is envisioned as a method in which the price could be communicated to the consumers and they may shift their loads from high price periods to the low price periods. The development and deployment of the FREEDM system necessitates controls of energy and power at the point of end use. In this thesis, the main objective is to develop the control model of the Energy Management System (EMS). The energy and power management in the FREEDM system is digitally controlled therefore all signals containing system states are discrete. The EMS is modeled as a discrete closed loop transfer function in the z-domain. A breakdown of power and energy control devices such as EMS components may result in energy con-sumption error. This leads to one of the main focuses of the thesis which is to identify and study component failures of the designed control system. Moreover, H-infinity ro-bust control method is applied to ensure effectiveness of the control architecture. A focus of the study is cyber security attack, specifically bad data detection in price. Test cases are used to illustrate the performance of the EMS control design, the effect of failure modes and the application of robust control technique. The EMS was represented by a linear z-domain model. The transfer function be-tween the pricing signal and the demand response was designed and used as a test bed. EMS potential failure modes were identified and studied. Three bad data detection meth-odologies were implemented and a voting policy was used to declare bad data. The run-ning mean and standard deviation analysis method proves to be the best method to detect bad data. An H-infinity robust control technique was applied for the first time to design discrete EMS controller for the FREEDM system.
Enabling Automated Dynamic Demand Response: From Theory to Practice
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frincu, Marc; Chelmis, Charalampos; Aman, Saima
2015-07-14
Demand response (DR) is a technique used in smart grids to shape customer load during peak hours. Automated DR offers utilities a fine grained control and a high degree of confidence in the outcome. However the impact on the customer's comfort means this technique is more suited for industrial and commercial settings than for residential homes. In this paper we propose a system for achieving automated controlled DR in a heterogeneous environment. We present some of the main issues arising in building such a system, including privacy, customer satisfiability, reliability, and fast decision turnaround, with emphasis on the solutions wemore » proposed. Based on the lessons we learned from empirical results we describe an integrated automated system for controlled DR on the USC microgrid. Results show that while on a per building per event basis the accuracy of our prediction and customer selection techniques varies, it performs well on average when considering several events and buildings.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-14
... industries can afford controls costing 10% of profits or more without impacting economic viability. EJ..., economic impact on each sector of the industry, output demand elasticity, etc. Response to EJ #4: Paragraph... useful information, but we also acknowledge that additional economic information could be helpful and...
Towards a Theory of Psychosocial Development and Fertility Control.
ERIC Educational Resources Information Center
Cvetkovich, George
It is popularly held that the low rate of birth control use among sexually-active American teenagers is primarily due to their immaturity. Many teenagers are commencing their sexual careers prior to acquisition of the social and cognitive abilities demanded by responsible contraceptive use. A general decision-making framework can be used to create…
Work and Health among Latina Mothers in Farmworker Families
Arcury, Thomas A.; Trejo, Grisel; Suerken, Cynthia K.; Grzywacz, Joseph G.; Ip, Edward H.; Quandt, Sara A.
2014-01-01
Background Work organization is important for the health of vulnerable workers, particularly women. This analysis describes work organization for Latinas in farmworker families and delineates the associations of work organization with health indicators. Methods 220 Latino women in farmworker families completed interviews from October 2012 - July 2013. Interviews addressed job structure, job demand, job control, and job support. Health measures included stress, depressive symptoms, physical activity, family conflict, and family economic security. Results Three-fifths of the women were employed. Several work organization dimensions, including shift, psychological demand, work safety climate, and benefits, were associated with participant health as expected, based on the work organization and job demands-control-support models. Conclusions Research should address women's health and specific work responsibilities. Occupational safety policy must consider the importance of work organization in the health of vulnerable workers. PMID:25742536
Design of demand side response model in energy internet demonstration park
NASA Astrophysics Data System (ADS)
Zhang, Q.; Liu, D. N.
2017-08-01
The implementation of demand side response can bring a lot of benefits to the power system, users and society, but there are still many problems in the actual operation. Firstly, this paper analyses the current situation and problems of demand side response. On this basis, this paper analyses the advantages of implementing demand side response in the energy Internet demonstration park. Finally, the paper designs three kinds of feasible demand side response modes in the energy Internet demonstration park.
Sekhar, P C; Mishra, S
2016-08-01
This paper proposes a novel, smart energy management scheme for a microgrid, consisting of a diesel generator and power electronic converter interfaced renewable energy-based generators, such as photovoltaic (PV) and fuel cell, for frequency regulation without any storage. In the proposed strategy, output of the PV is controlled in coordination with other generators using neurofuzzy controller, either only for transient frequency regulation or for both transient and steady-state frequency regulation, depending on the load demand, thereby eliminating the huge storage requirements. The option of demand response control is also explored along with the generation control. For accurate and quick tracking of maximum power point and its associated reserve power from the PV generator, this paper also proposes a novel adaptive-predictor-corrector-based tracking mechanism.
Robust Unit Commitment Considering Uncertain Demand Response
Liu, Guodong; Tomsovic, Kevin
2014-09-28
Although price responsive demand response has been widely accepted as playing an important role in the reliable and economic operation of power system, the real response from demand side can be highly uncertain due to limited understanding of consumers' response to pricing signals. To model the behavior of consumers, the price elasticity of demand has been explored and utilized in both research and real practice. However, the price elasticity of demand is not precisely known and may vary greatly with operating conditions and types of customers. To accommodate the uncertainty of demand response, alternative unit commitment methods robust to themore » uncertainty of the demand response require investigation. In this paper, a robust unit commitment model to minimize the generalized social cost is proposed for the optimal unit commitment decision taking into account uncertainty of the price elasticity of demand. By optimizing the worst case under proper robust level, the unit commitment solution of the proposed model is robust against all possible realizations of the modeled uncertain demand response. Numerical simulations on the IEEE Reliability Test System show the e ectiveness of the method. Finally, compared to unit commitment with deterministic price elasticity of demand, the proposed robust model can reduce the average Locational Marginal Prices (LMPs) as well as the price volatility.« less
Hierarchical Decentralized Control Strategy for Demand-Side Primary Frequency Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lian, Jianming; Hansen, Jacob; Marinovici, Laurentiu D.
The Grid Friendlymore » $$^\\textrm{TM}$$ Appliance~(GFA) controller, developed at Pacific Northwest National Laboratory, was designed for the purpose of autonomously switching off appliances by detecting under-frequency events. In this paper, a new frequency responsive load~(FRL) controller is first proposed by extending the functionality of the original GFA controller. The proposed FRL controller can autonomously switch on (or off) end-use loads by detecting over-frequency (or under-frequency) events through local frequency measurement. Then, a hierarchical decentralized control framework is developed for engaging the end-use loads to provide primary frequency response with the proposed FRL controller. The developed framework has several important features that are desirable in terms of providing primary frequency control. It not only exclusively maintains the autonomous operation of the end-use loads, but also effectively overcomes the stability issue associated with high penetration of FRLs. The simulation results illustrate the effectiveness of the developed hierarchical control framework for providing primary frequency response with the proposed FRL controller.« less
Kossek, Ellen Ernst; Thompson, Rebecca J; Lawson, Katie M; Bodner, Todd; Perrigino, Matthew B; Hammer, Leslie B; Buxton, Orfeu M; Almeida, David M; Moen, Phyllis; Hurtado, David A; Wipfli, Brad; Berkman, Lisa F; Bray, Jeremy W
2017-12-07
Although job stress models suggest that changing the work social environment to increase job resources improves psychological health, many intervention studies have weak designs and overlook influences of family caregiving demands. We tested the effects of an organizational intervention designed to increase supervisor social support for work and nonwork roles, and job control in a results-oriented work environment on the stress and psychological distress of health care employees who care for the elderly, while simultaneously considering their own family caregiving responsibilities. Using a group-randomized organizational field trial with an intent-to-treat design, 420 caregivers in 15 intervention extended-care nursing facilities were compared with 511 caregivers in 15 control facilities at 4 measurement times: preintervention and 6, 12, and 18 months. There were no main intervention effects showing improvements in stress and psychological distress when comparing intervention with control sites. Moderation analyses indicate that the intervention was more effective in reducing stress and psychological distress for caregivers who were also caring for other family members off the job (those with elders and those "sandwiched" with both child and elder caregiving responsibilities) compared with employees without caregiving demands. These findings extend previous studies by showing that the effect of organizational interventions designed to increase job resources to improve psychological health varies according to differences in nonwork caregiving demands. This research suggests that caregivers, especially those with "double-duty" elder caregiving at home and work and "triple-duty" responsibilities, including child care, may benefit from interventions designed to increase work-nonwork social support and job control. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Parker, Stacey L; Laurie, Kaitlan R; Newton, Cameron J; Jimmieson, Nerina L
2014-12-01
This experiment examined whether trait regulatory focus moderates the effects of task control on stress reactions during a demanding work simulation. Regulatory focus describes two ways in which individuals self-regulate toward desired goals: promotion and prevention. As highly promotion-focused individuals are oriented toward growth and challenge, it was expected that they would show better adaptation to demanding work under high task control. In contrast, as highly prevention-focused individuals are oriented toward safety and responsibility they were expected to show better adaptation under low task control. Participants (N=110) completed a measure of trait regulatory focus and then three trials of a demanding inbox activity under either low, neutral, or high task control. Heart rate variability (HRV), affective reactions (anxiety & task dissatisfaction), and task performance were measured at each trial. As predicted, highly promotion-focused individuals found high (compared to neutral) task control stress-buffering for performance. Moreover, highly prevention-focused individuals found high (compared to low) task control stress-exacerbating for dissatisfaction. In addition, highly prevention-focused individuals found low task control stress-buffering for dissatisfaction, performance, and HRV. However, these effects of low task control for highly prevention-focused individuals depended on their promotion focus. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Behboodi, Sahand; Chassin, David P.; Djilali, Ned
This study describes a new approach for solving the multi-area electricity resource allocation problem when considering both intermittent renewables and demand response. The method determines the hourly inter-area export/import set that maximizes the interconnection (global) surplus satisfying transmission, generation and load constraints. The optimal inter-area transfer set effectively makes the electricity price uniform over the interconnection apart from constrained areas, which overall increases the consumer surplus more than it decreases the producer surplus. The method is computationally efficient and suitable for use in simulations that depend on optimal scheduling models. The method is demonstrated on a system that represents Northmore » America Western Interconnection for the planning year of 2024. Simulation results indicate that effective use of interties reduces the system operation cost substantially. Excluding demand response, both the unconstrained and the constrained scheduling solutions decrease the global production cost (and equivalently increase the global economic surplus) by 12.30B and 10.67B per year, respectively, when compared to the standalone case in which each control area relies only on its local supply resources. This cost saving is equal to 25% and 22% of the annual production cost. Including 5% demand response, the constrained solution decreases the annual production cost by 10.70B, while increases the annual surplus by 9.32B in comparison to the standalone case.« less
Behboodi, Sahand; Chassin, David P.; Djilali, Ned; ...
2016-12-23
This study describes a new approach for solving the multi-area electricity resource allocation problem when considering both intermittent renewables and demand response. The method determines the hourly inter-area export/import set that maximizes the interconnection (global) surplus satisfying transmission, generation and load constraints. The optimal inter-area transfer set effectively makes the electricity price uniform over the interconnection apart from constrained areas, which overall increases the consumer surplus more than it decreases the producer surplus. The method is computationally efficient and suitable for use in simulations that depend on optimal scheduling models. The method is demonstrated on a system that represents Northmore » America Western Interconnection for the planning year of 2024. Simulation results indicate that effective use of interties reduces the system operation cost substantially. Excluding demand response, both the unconstrained and the constrained scheduling solutions decrease the global production cost (and equivalently increase the global economic surplus) by 12.30B and 10.67B per year, respectively, when compared to the standalone case in which each control area relies only on its local supply resources. This cost saving is equal to 25% and 22% of the annual production cost. Including 5% demand response, the constrained solution decreases the annual production cost by 10.70B, while increases the annual surplus by 9.32B in comparison to the standalone case.« less
Bus operators' responses to job strain: An experimental test of the job demand-control model.
Cendales-Ayala, Boris; Useche, Sergio Alejandro; Gómez-Ortiz, Viviola; Bocarejo, Juan Pablo
2017-10-01
The research aim was to test the Job Demand-Control (JDC) Model demands × Control interaction (or buffering) hypothesis in a simulated bus driving experiment. The buffering hypothesis was tested using a 2 (low and high demands) × 2 (low and high decision latitude) design with repeated measures on the second factor. A sample of 80 bus operators were randomly assigned to the low (n = 40) and high demands (n = 40) conditions. Demands were manipulated by increasing or reducing the number of stops to pick up passengers, and decision latitude by imposing or removing restrictions on the Rapid Transit Bus (BRT) operators' pace of work. Outcome variables include physiological markers (heart rate [HR], heart rate variability [HRV], breathing rate [BR], electromyography [EMG], and skin conductance [SC]), objective driving performance and self-report measurements of psychological wellbeing (psychological distress, interest/enjoyment [I/E], perceived competence, effort/importance [E/I], and pressure/tension [P/T]). It was found that job decision latitude moderates the effect of job demands on both physiological arousal (BR: F(1, 74) = 4.680, p = .034, SC: F(1, 75) = 6.769, p = .011, and EMG: F(1, 75) = 6.550, p = .013) and psychological well-being (P/T: F(1, 75) = 4.289, p = .042 and I/E: F(1, 74) = 4.548, p = .036). Consistently with the JDC model buffering hypothesis, the experimental findings suggest that increasing job decision latitude can moderate the negative effect of job demands on different psychophysiological outcomes. This finding is useful for designing organizational and clinical interventions in an occupational group at high risk of work stress-related disease. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Demand Response Resource Quantification with Detailed Building Energy Models
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hale, Elaine; Horsey, Henry; Merket, Noel
Demand response is a broad suite of technologies that enables changes in electrical load operations in support of power system reliability and efficiency. Although demand response is not a new concept, there is new appetite for comprehensively evaluating its technical potential in the context of renewable energy integration. The complexity of demand response makes this task difficult -- we present new methods for capturing the heterogeneity of potential responses from buildings, their time-varying nature, and metrics such as thermal comfort that help quantify likely acceptability of specific demand response actions. Computed with an automated software framework, the methods are scalable.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doebber, Ian; Deru, Michael; Trenbath, Kim
NREL worked with the Bonneville Power Administration's Technology Innovation Office to demonstrate a turnkey, retrofit technology that combines demand response (DR) and energy efficiency (EE) benefits for HVAC and lighting in retail buildings. As a secondary benefit, we also controlled various plug loads and electric hot water heaters (EHWH). The technology demonstrated was Transformative Wave's eIQ Building Management System (BMS) automatically responding to DR signals. The BMS controlled the HVAC rooftop units (RTU) using the CATALYST retrofit solution also developed by Transformative Wave. The non-HVAC loads were controlled using both hardwired and ZigBee wireless communication. The wireless controllers, manufactured bymore » Autani, were used when the building's electrical layout was too disorganized to leverage less expensive hardwired control. The six demonstration locations are within the Seattle metro area. Based on the assets curtailed by the BMS at each location, we projected the DR resource. We were targeting a 1.7 W/ft2 shed for the summer Day-Ahead events and a 0.7 W/ft2 shed for the winter events. While summarized in Table ES-1, only one summer DR event was conducted at Casino #2.« less
Code of Federal Regulations, 2014 CFR
2014-10-01
... public entities operating a demand responsive system for the general public. 37.77 Section 37.77...-rail vehicles by public entities operating a demand responsive system for the general public. (a) Except as provided in this section, a public entity operating a demand responsive system for the general...
Code of Federal Regulations, 2010 CFR
2010-10-01
... public entities operating a demand responsive system for the general public. 37.77 Section 37.77...-rail vehicles by public entities operating a demand responsive system for the general public. (a) Except as provided in this section, a public entity operating a demand responsive system for the general...
Code of Federal Regulations, 2011 CFR
2011-10-01
... public entities operating a demand responsive system for the general public. 37.77 Section 37.77...-rail vehicles by public entities operating a demand responsive system for the general public. (a) Except as provided in this section, a public entity operating a demand responsive system for the general...
Code of Federal Regulations, 2012 CFR
2012-10-01
... public entities operating a demand responsive system for the general public. 37.77 Section 37.77...-rail vehicles by public entities operating a demand responsive system for the general public. (a) Except as provided in this section, a public entity operating a demand responsive system for the general...
Schulte, Tilman; Müller-Oehring, Eva M; Sullivan, Edith V; Pfefferbaum, Adolf
2012-02-01
Alcohol dependence is associated with inhibitory control deficits, possibly related to abnormalities in frontoparietal cortical and midbrain function and connectivity. We examined functional connectivity and microstructural fiber integrity between frontoparietal and midbrain structures using a Stroop Match-to-Sample task with functional magnetic resonance imaging and diffusion tensor imaging in 18 alcoholic and 17 control subjects. Manipulation of color cues and response repetition sequences modulated cognitive demands during Stroop conflict. Despite similar lateral frontoparietal activity and functional connectivity in alcoholic and control subjects when processing conflict, control subjects deactivated the posterior cingulate cortex (PCC), whereas alcoholic subjects did not. Posterior cingulum fiber integrity predicted the degree of PCC deactivation in control but not alcoholic subjects. Also, PCC activity was modulated by executive control demands: activated during response switching and deactivated during response repetition. Alcoholics showed the opposite pattern: activation during repetition and deactivation during switching. Here, in alcoholic subjects, greater deviations from the normal PCC activity correlated with higher amounts of lifetime alcohol consumption. A functional dissociation of brain network connectivity between the groups further showed that control subjects exhibited greater corticocortical connectivity among middle cingulate, posterior cingulate, and medial prefrontal cortices than alcoholic subjects. In contrast, alcoholic subjects exhibited greater midbrain-orbitofrontal cortical network connectivity than control subjects. Degree of microstructural fiber integrity predicted robustness of functional connectivity. Thus, even subtle compromise of microstructural connectivity in alcoholism can influence modulation of functional connectivity and underlie alcohol-related cognitive impairment. Copyright © 2012 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
O'Donnell, Emma; Landolt, Kathleen; Hazi, Agnes; Dragano, Nico; Wright, Bradley J
2015-01-01
We assessed in an experimental design whether the stress response towards a work task was moderated by the autonomy to choose a break during the assigned time to complete the task. This setting is defined in accordance with the theoretical framework of the job-demand-control (JDC) model of work related stress. The findings from naturalistic investigations of a stress-buffering effect of autonomy (or 'buffer hypothesis') are equivocal and the experimental evidence is limited, especially with relation to physiological indices of stress. Our objective was to investigate if increased autonomy in a particular domain (break time control) was related with adaptive physiology using objective physiological markers of stress; heart rate variability (HRV) and salivary alpha amylase (sAA). We used a within-subject design and the 60 female participants were randomly assigned to an autonomy (free timing of break) and standard conditions (fixed timing of break) of a word processing task in a simulated office environment in a random order. Participants reported increased perceptions of autonomy, no difference in demand and performed worse in the task in the break-time autonomy versus the standard condition. The results revealed support for the manipulation of increased autonomy, but in the opposing direction. Increased autonomy was related with dysregulated physiological reactivity, synonymous with typical increased stress responses. Potentially, our findings may indicate that autonomy is not necessary a resource but could become an additional stressor when it adds additional complexity while the amount of work (demands) remains unchanged. Further, our findings underscore the need to collect objective physiological evidence of stress to supplement self-reported information. Self-report biases may partially explain the inconsistent findings with the buffer hypothesis. Copyright © 2014 Elsevier Ltd. All rights reserved.
Evaluating Job Demands and Control Measures for Use in Farm Worker Health Surveillance
Alterman, Toni; Gabbard, Susan; Grzywacz, Joseph G.; Shen, Rui; Li, Jia; Nakamoto, Jorge; Carroll, Daniel J.; Muntaner, Carles
2015-01-01
Workplace stress likely plays a role in health disparities; however, applying standard measures to studies of immigrants requires thoughtful consideration. The goal of this study was to determine the appropriateness of two measures of occupational stressors (‘decision latitude’ and ‘job demands’) for use with mostly immigrant Latino farm workers. Cross-sectional data from a pilot module containing a four-item measure of decision latitude and a two-item measure of job demands were obtained from a subsample (N = 409) of farm workers participating in the National Agricultural Workers Survey. Responses to items for both constructs were clustered toward the low end of the structured response-set. Percentages of responses of ‘very often’ and ‘always’ for each of the items were examined by educational attainment, birth country, dominant language spoken, task, and crop. Cronbach’s α, when stratified by subgroups of workers, for the decision latitude items were (0.65–0.90), but were less robust for the job demands items (0.25–0.72). The four-item decision latitude scale can be applied to occupational stress research with immigrant farm workers, and potentially other immigrant Latino worker groups. The short job demands scale requires further investigation and evaluation before suggesting widespread use. PMID:25138138
Krizman, Jennifer; Skoe, Erika; Marian, Viorica; Kraus, Nina
2014-01-01
Auditory processing is presumed to be influenced by cognitive processes – including attentional control – in a top-down manner. In bilinguals, activation of both languages during daily communication hones inhibitory skills, which subsequently bolster attentional control. We hypothesize that the heightened attentional demands of bilingual communication strengthens connections between cognitive (i.e., attentional control) and auditory processing, leading to greater across-trial consistency in the auditory evoked response (i.e., neural consistency) in bilinguals. To assess this, we collected passively-elicited auditory evoked responses to the syllable [da] and separately obtained measures of attentional control and language ability in adolescent Spanish-English bilinguals and English monolinguals. Bilinguals demonstrated enhanced attentional control and more consistent brainstem and cortical responses. In bilinguals, but not monolinguals, brainstem consistency tracked with language proficiency and attentional control. We interpret these enhancements in neural consistency as the outcome of strengthened attentional control that emerged from experience communicating in two languages. PMID:24413593
Recent advances in light-responsive on-demand drug-delivery systems
Linsley, Chase S; Wu, Benjamin M
2017-01-01
The convergence of wearable sensors and personalized medicine enhance the ability to sense and control the drug composition and dosage, as well as location and timing of administration. To date, numerous stimuli-triggered smart drug-delivery systems have been developed to detect changes in light, pH, temperature, biomolecules, electric field, magnetic field, ultrasound and mechanical forces. This review examines the major advances within the last 5 years for the three most common light-responsive drug delivery-on-demand strategies: photochemical, photoisomerization and photothermal. Examples are highlighted to illustrate progress of each strategy in drug delivery applications, and key limitations are identified to motivate future research to advance this important field. PMID:28088880
Recent advances in light-responsive on-demand drug-delivery systems.
Linsley, Chase S; Wu, Benjamin M
2017-02-01
The convergence of wearable sensors and personalized medicine enhance the ability to sense and control the drug composition and dosage, as well as location and timing of administration. To date, numerous stimuli-triggered smart drug-delivery systems have been developed to detect changes in light, pH, temperature, biomolecules, electric field, magnetic field, ultrasound and mechanical forces. This review examines the major advances within the last 5 years for the three most common light-responsive drug delivery-on-demand strategies: photochemical, photoisomerization and photothermal. Examples are highlighted to illustrate progress of each strategy in drug delivery applications, and key limitations are identified to motivate future research to advance this important field.
Attention Demand and Postural Control in Children with Hearing Deficit
ERIC Educational Resources Information Center
Derlich, Malgorzata; Krecisz, Krzysztof; Kuczynski, Michal
2011-01-01
To elucidate the mechanisms responsible for deteriorated postural control in children with hearing deficit (CwHD), we measured center-of-pressure (COP) variability, mean velocity and entropy in bipedal quiet stance (feet together) with or without the concurrent cognitive task (reaction to visual stimulus) on hard or foam surface in 29 CwHD and a…
Price Elasticity of Alcohol Demand in India.
Kumar, Santosh
2017-05-01
Using a household survey conducted in 2014, this study estimates price elasticity of demand (PED) for beer, country liquor and spirits in India. Ordinary least-square models were used to estimate the responsiveness in alcohol demand due to price change. A large number of control variables were included to adjust for potential confounding in the model. Inter-district variation in alcohol consumption is adjusted for by including district fixed effects. Alcohol prices are negatively associated with demand for alcoholic beverages. The PED ranged from -0.14 for spirits to -0.46 for country liquor. Low level of education was positively associated with spirits consumption. The magnitude of elasticity varied by rural-urban, education and gender. Results indicate that a policy mix of price controls and awareness campaigns would be most effective in tackling the adverse effects of harmful drinking in India. The demand for beer, country liquor and spirits is negatively associated with its own price. The elasticity estimates ranged from -0.14 for spirits to -0.44 for country liquor. The elasticity estimates varied by rural-urban, gender and by education levels of the drinkers. © The Author 2017. Medical Council on Alcohol and Oxford University Press. All rights reserved
DOT National Transportation Integrated Search
2016-08-01
The objective of this study is to develop a model for estimating demand for rural demand-response transit services for the general public. Lack of data for demand-response service characteristics and geographic coverage has limited the development of...
Hartman, J M; Kelder, H C; Ackerstaff, R G A; Swieten, H A; Vermeulen, F E E; Bogers, A J J C
2007-02-01
To correlate supraclavicular ultrasonography with angiographically patent and string sign left internal mammary artery (LIMA) to left anterior descending artery (LAD) grafts. Sixteen patients with a single LIMA anastomosis to the LAD were prospectively entered in a follow-up study. The supraclavicular ultrasonography of the LIMA origin was studied preoperatively and at 5.3+/-3.6 months and 1.7+/-0.4 year postoperatively. At the late postoperative ultrasonography electrocardiographically controlled hyperemic response was also studied for 6 min. Control angiography was performed at 1.5+/-0.8 year. Differences within groups were tested with a paired t-test and between groups with an unpaired t-test. Control angiography showed in 13 patients (group I) a patent LIMA graft and in 3 patients (group II) a string sign LIMA graft. Preoperative blood velocities were not significantly different between groups. Postoperatively, both groups revealed higher diastolic and lower systolic blood velocities compared to preoperative values. The blood velocities at rest did not change in group I and all velocities decreased in group II in time postoperatively. The blood velocities in maximal hyperemic response increased significantly within the groups and were not significantly different between the groups. No ischemia could be detected electrocardiographically during hyperemic response and no patient presented angina. Both groups showed a shift towards coronary type diastolic blood velocities at rest and at hyperaemic response. Significant hyperemic response was also present in string sign LIMA grafts and demonstrates response capacity to increased myocardial oxygen demand.
The effect of nicotine pre-exposure on demand for cocaine and sucrose in male rats.
Schwartz, Lindsay P; Kearns, David N; Silberberg, Alan
2018-06-01
The aim of the present study was to determine how nicotine pre-exposure affects the elasticity of demand for intravenous cocaine and for sucrose pellets in adult male rats. In Experiment 1, demand for cocaine was assessed in rats that had nicotine in their drinking water. Nicotine pre-exposure significantly decreased rats' willingness to defend cocaine consumption as the price (measured as the number of responses per cocaine infusion) increased compared with a control group with no nicotine pre-exposure. That is, nicotine increased the elasticity of demand for cocaine infusions. Experiment 2 repeated the first experiment, but with rats working for sucrose pellets instead of cocaine. Nicotine pre-exposure had no effect on the elasticity of demand for sucrose. This pattern of results suggests that nicotine pre-exposure can reduce the reinforcing effects of cocaine, but not sucrose, in adult male rats.
On-call work and physicians' turnover intention: the moderating effect of job strain.
Heponiemi, Tarja; Presseau, Justin; Elovainio, Marko
2016-01-01
Physician shortage and turnover are major problems worldwide. On-call duties may be among the risk factors of high turnover rates among physicians. We investigated whether having on-call duties is associated with physicians' turnover intention and whether job strain variables moderate this association. The present study was a cross-sectional questionnaire study among 3324 (61.6% women) Finnish physicians. The analyses were conducted using analyses of covariance adjusted for age, gender, response format, specialization status and employment sector. The results showed that job strain moderated the association between being on-call and turnover intention. The highest levels of turnover intention were among those who had on-call duties and high level of job strain characterized by high demands and low control opportunities. The lowest levels of turnover intention were among those who were not on-call and who had low strain involving low demands and high control. Also, job demands moderated the association between being on-call and turnover intention; turnover intention levels were higher among those with on-call duties and high demands than those being on-call and low demands. To conclude, working on-call was related to physicians' turnover intention particularly in those with high job strain. Health care organizations should focus more attention on working arrangements and scheduling of on-call work, provide a suitable working pace and implement means to increase physicians' participation and control over their job.
Pulkki-Råback, Laura; Elovainio, Marko; Virtanen, Marianna; Kivimäki, Mika; Hintsanen, Mirka; Hintsa, Taina; Jokela, Markus; Puttonen, Sampsa; Joensuu, Matti; Lipsanen, Jari; Raitakari, Olli T; Keltikangas-Järvinen, Liisa
2016-10-01
There have been calls to know more about vulnerability factors that may predispose to adverse health outcomes at work. We examined if childhood adverse experiences would affect vulnerability to psychosocial stress factors at work. A nationally representative sample of 1546 Finnish men and women was followed up from childhood to adulthood. Childhood adverse experiences consisted of socioeconomic and emotional factors. Job demands and job control were measured 21 years later, and depressive symptoms were measured 21 and 27 years after the childhood measurements. Job demands predicted depressive symptoms over 6 years, and the association was modified by childhood emotional adversity. Participants with three or more emotional adversities in childhood had more depressive symptoms in response to high job demands compared with participants with zero or one emotional adversities in childhood (Betas = -1.40 and -2.01, ps < 0.05 and <0.01). No such moderating effect by childhood adverse experiences was found for the association between job control and depressive symptoms. Although modest in effect size, these findings provide a developmental viewpoint for understanding the role of childhood experiences in work-related stress factors. Such knowledge can enhance understanding of individual differences in vulnerability to the demands of working life. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Auditory biological marker of concussion in children
Kraus, Nina; Thompson, Elaine C.; Krizman, Jennifer; Cook, Katherine; White-Schwoch, Travis; LaBella, Cynthia R.
2016-01-01
Concussions carry devastating potential for cognitive, neurologic, and socio-emotional disease, but no objective test reliably identifies a concussion and its severity. A variety of neurological insults compromise sound processing, particularly in complex listening environments that place high demands on brain processing. The frequency-following response captures the high computational demands of sound processing with extreme granularity and reliably reveals individual differences. We hypothesize that concussions disrupt these auditory processes, and that the frequency-following response indicates concussion occurrence and severity. Specifically, we hypothesize that concussions disrupt the processing of the fundamental frequency, a key acoustic cue for identifying and tracking sounds and talkers, and, consequently, understanding speech in noise. Here we show that children who sustained a concussion exhibit a signature neural profile. They have worse representation of the fundamental frequency, and smaller and more sluggish neural responses. Neurophysiological responses to the fundamental frequency partially recover to control levels as concussion symptoms abate, suggesting a gain in biological processing following partial recovery. Neural processing of sound correctly identifies 90% of concussion cases and clears 95% of control cases, suggesting this approach has practical potential as a scalable biological marker for sports-related concussion and other types of mild traumatic brain injuries. PMID:28005070
[Description of psychosocial risk factors in four companies].
Benavides, F G; Gimeno, D; Benach, J; Martínez, J M; Jarque, S; Berra, A; Devesa, J
2002-01-01
To describe the distribution of work-related psychosocial risk factor scores in four companies according to the personal and occupational characteristics of the workers. Cross-sectional study of a sample of 890 workers in four companies who participated in this study voluntarily. The overall response rate was 34.5%. A self-administrated questionnaire was used to measure the presence of demand, control and social support according to the workers' perceptions. Statistical analyses were performed using median and dispersion measures of psychosocial risk factors for each company separately, as well as description of their distribution according to personal and occupational variables. The median score for social support was almost always equal to 5 for all four companies. However, there was greater variability in psychological demand (between 13 and 16), and for control (between 20 and 26). Comparison of the scores for social and occupational variables revealed similar values for social support but not for control and demand, which showed greater variation according to sex (men), age group (less than 40 years) and occupation (clerks). Although the low response rate could limit the validity of our results, this is the first study to value the distribution of work-related psychosocial risk factor scores in four companies in Spain. Variability among companies for different groups of workers was found. This study could be useful for future studies exploring the feasibility of defining reference values for use in preventive measures.
29 CFR 20.55 - Second and subsequent notifications.
Code of Federal Regulations, 2010 CFR
2010-07-01
... second and subsequent demands for payment, if payment or other appropriate response is not received within the time specified by the initial demand. Unless a response to the first or second demand indicates that a further demand would be futile or the debtor's response does not require rebuttal, the...
Dramatic Demand Reduction In The Desert Southwest
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boehm, Robert; Hsieh, Sean; Lee, Joon
This report summarizes a project that was funded to the University of Nevada Las Vegas (UNLV), with subcontractors Pulte Homes and NV Energy. The project was motivated by the fact that locations in the Desert Southwest portion of the US demonstrate very high peak electrical demands, typically in the late afternoons in the summer. These high demands often require high priced power to supply the needs, and the large loads can cause grid supply problems. An approach was proposed through this contact that would reduce the peak electrical demands to an anticipated 65% of what code-built houses of the similarmore » size would have. It was proposed to achieve energy reduction through four approaches applied to a development of 185 homes in northwest part of Las Vegas named Villa Trieste. First, the homes would all be highly energy efficient. Secondly, each house would have a PV array installed on it. Third, an advanced demand response technique would be developed to allow the resident to have some control over the energy used. Finally, some type of battery storage would be used in the project. Pulte Homes designed the houses. The company considered initial cost vs. long-term savings and chose options that had relatively short paybacks. HERS (Home Energy Rating Service) ratings for the homes are approximately 43 on this scale. On this scale, code-built homes rate at 100, zero energy homes rate a 0, and Energy Star homes are 85. In addition a 1.764 Wp (peak Watt) rated PV array was used on each house. This was made up of solar shakes that were in visual harmony with the roofing material used. A demand response tool was developed to control the amount of electricity used during times of peak demand. While demand response techniques have been used in the utility industry for some time, this particular approach is designed to allow the customer to decide the degree of participation in the response activity. The temperature change in the residence can be decided by the residents by adjusting settings. In a sense the customer can choose between greater comfort and greater money savings during demand response circumstances. Finally a battery application was to be considered. Initially it was thought that a large battery (probably a sodium-sulfur type) would be installed. However, after the contract was awarded, it was determined that a single, centrally-located battery system would not be appropriate for many reasons, including that with the build out plan there would not be any location to put it. The price had risen substantially since the budget for the project was put together. Also, that type of battery has to be kept hot all the time, but its use was only sought for summer operation. Hence, individual house batteries would be used, and these are discussed at the end of this report. Many aspects of the energy use for climate control in selected houses were monitored before residents moved in. This was done both to understand the magnitude of the energy flows but also to have data that could be compared to the computer simulations. The latter would be used to evaluate various aspects of our plan. It was found that good agreement existed between actual energy use and computed energy use. Hence, various studies were performed via simulations. Performance simulations showed the impact on peak energy usage between a code built house of same size and shape compared to the Villa Trieste homes with and without the PV arrays on the latter. Computations were also used to understand the effect of varying orientations of the houses in this typical housing development, including the effect of PV electrical generation. Energy conservation features of the Villa Trieste homes decreased the energy use during peak times (as well as all others), but the resulting decreased peak occurred at about the same time as the code-built houses. Consideration of the PV generation decreases the grid energy use further during daylight hours, but did not extend long enough many days to decrease the peak. Hence, a demand response approach, as planned, was needed. With participation of the residents in the demand response program developed does enable the houses to reduce the peak demand between 66% and 72%, depending on the built years. This was addressed fully in the latter part the study and is described in the latter part of this report.« less
Larradet, Fanny; Barresi, Giacinto; Mattos, Leonardo S
2017-07-01
Eye-tracking (ET) is one of the most intuitive solutions for enabling people with severe motor impairments to control devices. Nevertheless, even such an effective assistive solution can detrimentally affect user experience during demanding tasks because of, for instance, the user's mental workload - using gaze-based controls for an extensive period of time can generate fatigue and cause frustration. Thus, it is necessary to design novel solutions for ET contexts able to improve the user experience, with particular attention to its aspects related to workload. In this paper, a pilot study evaluates the effects of a relaxation biofeedback system on the user experience in the context of a gaze-controlled task that is mentally and temporally demanding: ET-based gaming. Different aspects of the subjects' experience were investigated under two conditions of a gaze-controlled game. In the Biofeedback group (BF), the user triggered a command by means of voluntary relaxation, monitored through Galvanic Skin Response (GSR) and represented by visual feedback. In the No Biofeedback group (NBF), the same feedback was timed according to the average frequency of commands in BF. After the experiment, each subject filled out a user experience questionnaire. The results showed a general appreciation for BF, with a significant between-group difference in the perceived session time duration, with the latter being shorter for subjects in BF than for the ones in NBF. This result implies a lower mental workload for BF than for NBF subjects. Other results point toward a potential role of user's engagement in the improvement of user experience in BF. Such an effect highlights the value of relaxation biofeedback for improving the user experience in a demanding gaze-controlled task.
Nonlinear electro-optic tuning of plasmonic nano-filter
NASA Astrophysics Data System (ADS)
Kotb, Rehab; Ismail, Yehea; Swillam, Mohamed A.
2015-03-01
Efficient, easy and accurate tuning techniques to a plasmonic nano-filter are investigated. The proposed filter supports both blue and red shift in the resonance wavelength. By varying the refractive index with a very small change (in the order of 10-3), the resonance wavelength can be controlled efficiently. Using Pockels material, an electrical tuning to the response of the filter is demonstrated. In addition, the behavior of the proposed filter can be controlled optically using Kerr material. A new approach of multi-stage electro-optic controlling is introduced. By cascading two stages and filling the first stage with pockels material and the second stage with kerr material, the output response of the second stage can be controlled by controlling the output response of the first stage electrically. Due to the sharp response of the proposed filter, 60nm shift in the resonance wavelength per 10 voltages is achieved. This nano-filter has compact size, low loss, sharp response and wide range of tunabilty which is highly demandable in many biological and sensing applications.
Assessment of Optimal Flexibility in Ensemble of Frequency Responsive Loads
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kundu, Soumya; Hansen, Jacob; Lian, Jianming
2018-04-19
Potential of electrical loads in providing grid ancillary services is often limited due to the uncertainties associated with the load behavior. A knowledge of the expected uncertainties with a load control program would invariably yield to better informed control policies, opening up the possibility of extracting the maximal load control potential without affecting grid operations. In the context of frequency responsive load control, a probabilistic uncertainty analysis framework is presented to quantify the expected error between the target and actual load response, under uncertainties in the load dynamics. A closed-form expression of an optimal demand flexibility, minimizing the expected errormore » in actual and committed flexibility, is provided. Analytical results are validated through Monte Carlo simulations of ensembles of electric water heaters.« less
Jacobson, Lisa A.; Ryan, Matthew; Denckla, Martha B.; Mostofsky, Stewart H.; Mahone, E. Mark
2013-01-01
Children with Attention-Deficit/Hyperactivity Disorder (ADHD) demonstrate increased response variability compared with controls, which is thought to be associated with deficits in attention regulation and response control that subsequently affect performance of more cognitively demanding tasks, such as reading. The present study examined response variability during a computerized simple reaction time (RT) task in 67 children. Ex-Gaussian analyses separated the response time distribution into normal (mu and sigma) and exponential (tau) components; the association of each with reading fluency was examined. Children with ADHD had significantly slower, more variable, and more skewed RTs compared with controls. After controlling for ADHD symptom severity, tau (but not mu or mean RT) was significantly associated with reduced reading fluency, but not with single word reading accuracy. These data support the growing evidence that RT variability, but not simply slower mean response speed, is the characteristic of youth with ADHD and that longer response time latencies (tau) may be implicated in the poorer academic performance associated with ADHD. PMID:23838684
Jacobson, Lisa A; Ryan, Matthew; Denckla, Martha B; Mostofsky, Stewart H; Mahone, E Mark
2013-11-01
Children with Attention-Deficit/Hyperactivity Disorder (ADHD) demonstrate increased response variability compared with controls, which is thought to be associated with deficits in attention regulation and response control that subsequently affect performance of more cognitively demanding tasks, such as reading. The present study examined response variability during a computerized simple reaction time (RT) task in 67 children. Ex-Gaussian analyses separated the response time distribution into normal (mu and sigma) and exponential (tau) components; the association of each with reading fluency was examined. Children with ADHD had significantly slower, more variable, and more skewed RTs compared with controls. After controlling for ADHD symptom severity, tau (but not mu or mean RT) was significantly associated with reduced reading fluency, but not with single word reading accuracy. These data support the growing evidence that RT variability, but not simply slower mean response speed, is the characteristic of youth with ADHD and that longer response time latencies (tau) may be implicated in the poorer academic performance associated with ADHD.
12 CFR 602.23 - Responses to demands served on FCA employees.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Responses to demands served on FCA employees. 602.23 Section 602.23 Banks and Banking FARM CREDIT ADMINISTRATION ADMINISTRATIVE PROVISIONS RELEASING....23 Responses to demands served on FCA employees. (a) An employee served with a demand or a subpoena...
A longitudinal test of the demand-control model using specific job demands and specific job control.
de Jonge, Jan; van Vegchel, Natasja; Shimazu, Akihito; Schaufeli, Wilmar; Dormann, Christian
2010-06-01
Supportive studies of the demand-control (DC) model were more likely to measure specific demands combined with a corresponding aspect of control. A longitudinal test of Karasek's (Adm Sci Q. 24:285-308, 1) job strain hypothesis including specific measures of job demands and job control, and both self-report and objectively recorded well-being. Job strain hypothesis was tested among 267 health care employees from a two-wave Dutch panel survey with a 2-year time lag. Significant demand/control interactions were found for mental and emotional demands, but not for physical demands. The association between job demands and job satisfaction was positive in case of high job control, whereas this association was negative in case of low job control. In addition, the relation between job demands and psychosomatic health symptoms/sickness absence was negative in case of high job control and positive in case of low control. Longitudinal support was found for the core assumption of the DC model with specific measures of job demands and job control as well as self-report and objectively recorded well-being.
Thermal Control Technologies for Complex Spacecraft
NASA Technical Reports Server (NTRS)
Swanson, Theodore D.
2004-01-01
Thermal control is a generic need for all spacecraft. In response to ever more demanding science and exploration requirements, spacecraft are becoming ever more complex, and hence their thermal control systems must evolve. This paper briefly discusses the process of technology development, the state-of-the-art in thermal control, recent experiences with on-orbit two-phase systems, and the emerging thermal control technologies to meet these evolving needs. Some "lessons learned" based on experience with on-orbit systems are also presented.
Brashier, Nadia M.
2015-01-01
The human brain encodes experience in an integrative fashion by binding together the various features of an event (i.e., stimuli and responses) into memory “event files.” A subsequent reoccurrence of an event feature can then cue the retrieval of the memory file to “prime” cognition and action. Intriguingly, recent behavioral studies indicate that, in addition to linking concrete stimulus and response features, event coding may also incorporate more abstract, “internal” event features such as attentional control states. In the present study, we used fMRI in healthy human volunteers to determine the neural mechanisms supporting this type of holistic event binding. Specifically, we combined fMRI with a task protocol that dissociated the expression of event feature-binding effects pertaining to concrete stimulus and response features, stimulus categories, and attentional control demands. Using multivariate neural pattern classification, we show that the hippocampus and putamen integrate event attributes across all of these levels in conjunction with other regions representing concrete-feature-selective (primarily visual cortex), category-selective (posterior frontal cortex), and control demand-selective (insula, caudate, anterior cingulate, and parietal cortex) event information. Together, these results suggest that the hippocampus and putamen are involved in binding together holistic event memories that link physical stimulus and response characteristics with internal representations of stimulus categories and attentional control states. These bindings then presumably afford shortcuts to adaptive information processing and response selection in the face of recurring events. SIGNIFICANCE STATEMENT Memory binds together the different features of our experience, such as an observed stimulus and concurrent motor responses, into so-called event files. Recent behavioral studies suggest that the observer's internal attentional state might also become integrated into the event memory. Here, we used fMRI to determine the brain areas responsible for binding together event information pertaining to concrete stimulus and response features, stimulus categories, and internal attentional control states. We found that neural signals in the hippocampus and putamen contained information about all of these event attributes and could predict behavioral priming effects stemming from these features. Therefore, medial temporal lobe and dorsal striatum structures appear to be involved in binding internal control states to event memories. PMID:26538657
Age-Related Brain Activation Changes during Rule Repetition in Word-Matching.
Methqal, Ikram; Pinsard, Basile; Amiri, Mahnoush; Wilson, Maximiliano A; Monchi, Oury; Provost, Jean-Sebastien; Joanette, Yves
2017-01-01
Objective: The purpose of this study was to explore the age-related brain activation changes during a word-matching semantic-category-based task, which required either repeating or changing a semantic rule to be applied. In order to do so, a word-semantic rule-based task was adapted from the Wisconsin Sorting Card Test, involving the repeated feedback-driven selection of given pairs of words based on semantic category-based criteria. Method: Forty healthy adults (20 younger and 20 older) performed a word-matching task while undergoing a fMRI scan in which they were required to pair a target word with another word from a group of three words. The required pairing is based on three word-pair semantic rules which correspond to different levels of semantic control demands: functional relatedness, moderately typical-relatedness (which were considered as low control demands), and atypical-relatedness (high control demands). The sorting period consisted of a continuous execution of the same sorting rule and an inferred trial-by-trial feedback was given. Results: Behavioral performance revealed increases in response times and decreases of correct responses according to the level of semantic control demands (functional vs. typical vs. atypical) for both age groups (younger and older) reflecting graded differences in the repetition of the application of a given semantic rule. Neuroimaging findings of significant brain activation showed two main results: (1) Greater task-related activation changes for the repetition of the application of atypical rules relative to typical and functional rules, and (2) Changes (older > younger) in the inferior prefrontal regions for functional rules and more extensive and bilateral activations for typical and atypical rules. Regarding the inter-semantic rules comparison, only task-related activation differences were observed for functional > typical (e.g., inferior parietal and temporal regions bilaterally) and atypical > typical (e.g., prefrontal, inferior parietal, posterior temporal, and subcortical regions). Conclusion: These results suggest that healthy cognitive aging relies on the adaptive changes of inferior prefrontal resources involved in the repetitive execution of semantic rules, thus reflecting graded differences in support of task demands.
Dong, Debo; Wang, Yulin; Jackson, Todd; Chen, Shuaiyu; Wang, Yu; Zhou, Feng; Chen, Hong
2016-10-01
Theory and associated research indicate that people with elevated restrained eating (RE) scores have higher risk for binge eating, future bulimic symptom onset and weight gain. Previous imaging studies have suggested hyper-responsive reward brain area activation in response to food cues contributes to this risk but little is known about associated neural impulse control mechanisms, especially when considering links between depleted cognitive resources related to unsuccessful RE. Towards illuminating this issue, we used a chocolate-specific delayed discounting (DD) task to investigate relations between RE scores, behavior impulsivity, and corresponding neural impulse control correlates in a functional magnetic resonance imaging (fMRI) study of 27 young women. Specifically, participants were required to choose between more immediate, smaller versus delayed, larger hypothetical chocolate rewards following initial consumption of a chocolate. As predicted, RE scores were correlated positively with behavior impulse control levels. More critically, higher RE scores were associated with stronger activation in impulse control region, the dorsal-lateral prefrontal cortex (DLPFC) during the completion of difficult decision trials reflecting higher cognitive demands and resource depletion relative to easy decision trials. Exploratory analyses revealed a positive correlation between RE scores and activity in a reward system hub, the right striatum. Moreover, a positive correlation between left DLPFC and striatum activation was posited to reflect, in part, impulse control region compensation in response to stronger reward signal among women with RE elevations. Findings suggested impulse control lapses may contribute to difficulties in maintaining RE, particularly when cognitive demands are high. Copyright © 2016. Published by Elsevier Ltd.
Heart rate variability and cognitive processing: The autonomic response to task demands.
Luque-Casado, Antonio; Perales, José C; Cárdenas, David; Sanabria, Daniel
2016-01-01
This study investigated variations in heart rate variability (HRV) as a function of cognitive demands. Participants completed an execution condition including the psychomotor vigilance task, a working memory task and a duration discrimination task. The control condition consisted of oddball versions (participants had to detect the rare event) of the tasks from the execution condition, designed to control for the effect of the task parameters (stimulus duration and stimulus rate) on HRV. The NASA-TLX questionnaire was used as a subjective measure of cognitive workload across tasks and conditions. Three major findings emerged from this study. First, HRV varied as a function of task demands (with the lowest values in the working memory task). Second, and crucially, we found similar HRV values when comparing each of the tasks with its oddball control equivalent, and a significant decrement in HRV as a function of time-on-task. Finally, the NASA-TLX results showed larger cognitive workload in the execution condition than in the oddball control condition, and scores variations as a function of task. Taken together, our results suggest that HRV is highly sensitive to overall demands of sustained attention over and above the influence of other cognitive processes suggested by previous literature. In addition, our study highlights a potential dissociation between objective and subjective measures of mental workload, with important implications in applied settings. Copyright © 2015 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lu, Shuai; Elizondo, Marcelo A.; Samaan, Nader A.
2011-10-10
The focus of this paper is to design control strategies for distributed energy resources (DERs) to maximize the use of wind power in a rural microgrid. In such a system, it may be economical to harness wind power to reduce the consumption of fossil fuels for electricity production. In this work, we develop control strategies for DERs, including diesel generators, energy storage and demand response, to achieve high penetration of wind energy in a rural microgrid. Combinations of centralized (direct control) and decentralized (autonomous response) control strategies are investigated. Detailed dynamic models for a rural microgrid are built to conductmore » simulations. The system response to large disturbances and frequency regulation are tested. It is shown that optimal control coordination of DERs can be achieved to maintain system frequency while maximizing wind power usage and reducing the wear and tear on fossil fueled generators.« less
Gutowski, Stacie M.; Shoemaker, James T.; Templeman, Kellie L.; Wei, Yang; Latour, Robert A.; Bellamkonda, Ravi V.; LaPlaca, Michelle C.; García, Andrés J.
2015-01-01
Neural electrodes are an important part of brain-machine interface devices that can restore functionality to patients with sensory and movement disorders. Chronically implanted neural electrodes induce an unfavorable tissue response which includes inflammation, scar formation, and neuronal cell death, eventually causing loss of electrode function. We developed a poly(ethylene glycol) hydrogel coating for neural electrodes with non-fouling characteristics, incorporated an anti-inflammatory agent, and engineered a stimulus-responsive degradable portion for on-demand release of the anti-inflammatory agent in response to inflammatory stimuli. This coating reduces in vitro glial cell adhesion, cell spreading, and cytokine release compared to uncoated controls. We also analyzed the in vivo tissue response using immunohistochemistry and microarray qRT-PCR. Although no differences were observed among coated and uncoated electrodes for inflammatory cell markers, lower IgG penetration into the tissue around PEG+IL-1Ra coated electrodes indicates an improvement in blood-brain barrier integrity. Gene expression analysis showed higher expression of IL-6 and MMP-2 around PEG+IL-1Ra samples, as well as an increase in CNTF expression, an important marker for neuronal survival. Importantly, increased neuronal survival around coated electrodes compared to uncoated controls was observed. Collectively, these results indicate promising findings for an engineered coating to increase neuronal survival and improve tissue response around implanted neural electrodes. PMID:25617126
NASA Technical Reports Server (NTRS)
1974-01-01
The transient and steady state response of the respiratory control system for variations in volumetric fractions of inspired gases and special system parameters are modeled. The program contains the capability to change workload. The program is based on Grodins' respiratory control model and can be envisioned as a feedback control system comprised of a plant (the controlled system) and the regulating component (controlling system). The controlled system is partitioned into 3 compartments corresponding to lungs, brain, and tissue with a fluid interconnecting patch representing the blood.
FORESEE™ User-Centric Energy Automation
DOE Office of Scientific and Technical Information (OSTI.GOV)
FORESEE™ is a home energy management system (HEMS) that provides a user centric energy automation solution for residential building occupants. Built upon advanced control and machine learning algorithms, FORESEE intelligently manages the home appliances and distributed energy resources (DERs) such as photovoltaics and battery storage in a home. Unlike existing HEMS in the market, FORESEE provides a tailored home automation solution for individual occupants by learning and adapting to their preferences on cost, comfort, convenience and carbon. FORESEE improves not only the energy efficiency of the home but also its capability to provide grid services such as demand response. Highlymore » reliable demand response services are likely to be incentivized by utility companies, making FORESEE economically viable for most homes.« less
Is youth smoking responsive to cigarette prices? Evidence from low- and middle-income countries.
Kostova, Deliana; Ross, Hana; Blecher, Evan; Markowitz, Sara
2011-11-01
To estimate the price elasticity of cigarette demand among youth in low- and middle-income countries (LMIC). The Global Youth Tobacco Survey was used to obtain data on the smoking behaviour of 315,353 adolescents from 17 LMIC. Two-part model of cigarette demand with country fixed effects. The first part estimates the impact of prices on smoking participation while the second part estimates the impact of prices on the number of cigarettes smoked among current smokers. Besides controlling for individual characteristics such as Age, Gender, Parental Smoking and availability of Pocket Money, the authors control for confounding environmental factors such as anti-smoking sentiment, the prevalence of cigarette advertising and anti-tobacco media messAges, and ease of purchasing cigarettes. All countries in this study are represented with at least two observations over time, which allows us to control for unobserved country characteristics and/or policies that may influence smoking patterns within countries. Cigarette price is an important determinant of smoking. The estimated price elasticity of smoking participation is -0.74, and the estimated price elasticity of conditional cigarette demand is approximately -1.37. The total price elasticity of cigarette demand is -2.11, implying that an increase in price of 10% would reduce youth cigarette consumption by 21.1% at the mean.
Burnout and engagement at work as a function of demands and control.
Demerouti, E; Bakker, A B; de Jonge, J; Janssen, P P; Schaufeli, W B
2001-08-01
The present study was designed to test the demand-control model using indicators of both health impairment and active learning or motivation. A total of 381 insurance company employees participated in the study. Discriminant analysis was used to examine the relationship between job demands and job control on one hand and health impairment and active learning on the other. The amount of demands and control could be predicted on the basis of employees' perceived health impairment (exhaustion and health complaints) and active learning (engagement and commitment). Each of the four combinations of demand and control differentially affected the perception of strain or active learning. Job demands were the most clearly related to health impairment, whereas job control was the most clearly associated with active learning. These findings partly contradict the demand-control model, especially with respect to the validity of the interaction between demand and control. Job demands and job control seem to initiate two essentially independent processes, and this occurrence is consistent with the recently proposed job demands-resources model.
Influences of Plant Traits on Immune Responses of Specialist and Generalist Herbivores
Lampert, Evan
2012-01-01
Specialist and generalist insect herbivore species often differ in how they respond to host plant traits, particularly defensive traits, and these responses can include weakened or strengthened immune responses to pathogens and parasites. Accurate methods to measure immune response in the presence and absence of pathogens and parasites are necessary to determine whether susceptibility to these natural enemies is reduced or increased by host plant traits. Plant chemical traits are particularly important in that host plant metabolites may function as antioxidants beneficial to the immune response, or interfere with the immune response of both specialist and generalist herbivores. Specialist herbivores that are adapted to process and sometimes accumulate specific plant compounds may experience high metabolic demands that may decrease immune response, whereas the metabolic demands of generalist species differ due to more broad-substrate enzyme systems. However, the direct deleterious effects of plant compounds on generalist herbivores may weaken their immune responses. Further research in this area is important given that the ecological relevance of plant traits to herbivore immune responses is equally important in natural systems and agroecosystems, due to potential incompatibility of some host plant species and cultivars with biological control agents of herbivorous pests. PMID:26466545
DOT National Transportation Integrated Search
1963-11-01
Subjects were exposed to a 10-day habituation series of 200 CW accelerations in total darkness while performing attention-demanding tasks. Decelerations were sub-threshold. Preliminary and post-tests indicated that slow-phase nystagmus and duration o...
In-group biases and oculomotor responses: beyond simple approach motivation.
Moradi, Zahra Zargol; Manohar, Sanjay; Duta, Mihaela; Enock, Florence; Humphreys, Glyn W
2018-05-01
An in-group bias describes an individual's bias towards a group that they belong to. Previous studies suggest that in-group bias facilitates approach motor responses, but disrupts avoidance ones. Such motor biases are shown to be more robust when the out-group is threatening. We investigated whether, under controlled visual familiarity and complexity, in-group biases still promote pro-saccade and hinder anti-saccades oculomotor responses. Participants first learned to associate an in-group or out-group label with an arbitrary shape. They were then instructed to listen to the group-relevant auditory cue (name of own and a rival university) followed by one of the shapes. Half of the participants were instructed to look towards the visual target if it matched the preceding group-relevant auditory cue and to look away from it if it did not match. The other half of the participants received reversed instructions. This design allowed us to orthogonally manipulate the effect of in-group bias and cognitive control demand on oculomotor responses. Both pro- and anti-saccades were faster and more accurate following the in-group auditory cue. Independently, pro-saccades were performed better than anti-saccades, and match judgements were faster and more accurate than non-match judgements. Our findings indicate that under higher cognitive control demands individuals' oculomotor responses improved following the motivationally salient cue (in-group). Our findings have important implications for learning and cognitive control in a social context. As we included rival groups, our results might to some extent reflect the effects of out-group threat. Future studies could extend our findings using non-threatening out-groups instead.
Price elasticity of on- and off-premises demand for alcoholic drinks: A Tobit analysis.
Jiang, Heng; Livingston, Michael; Room, Robin; Callinan, Sarah
2016-06-01
Understanding how price policies will affect alcohol consumption requires estimates of the impact of price on consumption among different types of drinkers and across different consumption settings. This study aims to estimate how changes in price could affect alcohol demand across different beverages, different settings (on-premise, e.g., bars, restaurants and off-premise, e.g., liquor stores, supermarkets), and different levels of drinking and income. Tobit analysis is employed to estimate own- and cross-price elasticities of alcohol demand among 11 subcategories of beverage based on beverage type and on- or off-premise supply, using cross-sectional data from the Australian arm of the International Alcohol Control Survey 2013. Further elasticity estimates were derived for sub-groups of drinkers based on their drinking and income levels. The results suggest that demand for nearly every subcategory of alcohol significantly responds to its own price change, except for on-premise spirits and ready-to-drink spirits. The estimated demand for off-premise beverages is more strongly affected by own price changes than the same beverages in on-premise settings. Demand for off-premise regular beer and off-premise cask wine is more price responsive than demand for other beverages. Harmful drinkers and lower income groups appear more price responsive than moderate drinkers and higher income groups. Our findings suggest that alcohol price policies, such as increasing alcohol taxes or introducing a minimum unit price, can reduce alcohol demand. Price appears to be particularly effective for reducing consumption and as well as alcohol-related harm among harmful drinkers and lower income drinkers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Photosynthesis of young apple trees in response to low sink demand under different air temperatures.
Fan, Pei G; Li, Lian S; Duan, Wei; Li, Wei D; Li, Shao H
2010-03-01
Gas exchange, chlorophyll fluorescence, photosynthetic end products and related enzymes in source leaves in response to low sink demand after girdling to remove the root sink were assessed in young apple trees (Malus pumila) grown in two greenhouses with different air temperatures for 5 days. Compared with the non-girdled control in the low-temperature greenhouse (diurnal maximum air temperature <32 degrees C), low sink demand resulted in lower net photosynthetic rate (P(n)), stomatal conductance (g(s)) and transpiration rate (E) but higher leaf temperature on Day 5, while in the high-temperature greenhouse (diurnal maximum air temperature >36 degrees C), P(n), g(s) and E declined from Day 3 onwards. Moreover, gas exchange responded more to low sink demand in the high-temperature greenhouse than in the low-temperature greenhouse. Decreased P(n) at low sink demand was accompanied by lower intercellular CO(2) concentrations in the low-temperature greenhouse. However, decreased maximal photochemical efficiency, potential activity, efficiency of excitation capture, actual efficiency and photochemical quenching, with increased minimal fluorescence and non-photochemical quenching of photosystem II (PSII), were observed in low sink demand leaves only in the high-temperature greenhouse. In addition, low sink demand increased leaf starch and soluble carbohydrate content in both greenhouses but did not result in lower activity of enzymes involved in metabolism. Thus, decreased P(n) under low sink demand was independent of a direct effect of end-product feedback but rather depended on a high temperature threshold. The lower P(n) was likely due to stomatal limitation in the low-temperature greenhouse, but mainly due to non-stomatal limitation in the high-temperature greenhouse.
75 FR 15362 - Demand Response Compensation in Organized Wholesale Energy Markets
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-29
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission 18 CFR Part 35 [Docket No. RM10-17-000... FERC ] 61,213, PJM Interconnection, LLC, Docket No. EL09-68-000 Notice of Proposed Rulemaking Table of... Emergency Demand Response; NYISO's Emergency Demand Response Program; PJM's Emergency Load Response; and ISO...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Starke, Michael R; Kirby, Brendan J; Kueck, John D
2009-02-01
Demand response is the largest underutilized reliability resource in North America. Historic demand response programs have focused on reducing overall electricity consumption (increasing efficiency) and shaving peaks but have not typically been used for immediate reliability response. Many of these programs have been successful but demand response remains a limited resource. The Federal Energy Regulatory Commission (FERC) report, 'Assessment of Demand Response and Advanced Metering' (FERC 2006) found that only five percent of customers are on some form of demand response program. Collectively they represent an estimated 37,000 MW of response potential. These programs reduce overall energy consumption, lower greenmore » house gas emissions by allowing fossil fuel generators to operate at increased efficiency and reduce stress on the power system during periods of peak loading. As the country continues to restructure energy markets with sophisticated marginal cost models that attempt to minimize total energy costs, the ability of demand response to create meaningful shifts in the supply and demand equations is critical to creating a sustainable and balanced economic response to energy issues. Restructured energy market prices are set by the cost of the next incremental unit of energy, so that as additional generation is brought into the market, the cost for the entire market increases. The benefit of demand response is that it reduces overall demand and shifts the entire market to a lower pricing level. This can be very effective in mitigating price volatility or scarcity pricing as the power system responds to changing demand schedules, loss of large generators, or loss of transmission. As a global producer of alumina, primary aluminum, and fabricated aluminum products, Alcoa Inc., has the capability to provide demand response services through its manufacturing facilities and uniquely through its aluminum smelting facilities. For a typical aluminum smelter, electric power accounts for 30% to 40% of the factory cost of producing primary aluminum. In the continental United States, Alcoa Inc. currently owns and/or operates ten aluminum smelters and many associated fabricating facilities with a combined average load of over 2,600 MW. This presents Alcoa Inc. with a significant opportunity to respond in areas where economic opportunities exist to help mitigate rising energy costs by supplying demand response services into the energy system. This report is organized into seven chapters. The first chapter is the introduction and discusses the intention of this report. The second chapter contains the background. In this chapter, topics include: the motivation for Alcoa to provide demand response; ancillary service definitions; the basics behind aluminum smelting; and a discussion of suggested ancillary services that would be particularly useful for Alcoa to supply. Chapter 3 is concerned with the independent system operator, the Midwest ISO. Here the discussion examines the evolving Midwest ISO market structure including specific definitions, requirements, and necessary components to provide ancillary services. This section is followed by information concerning the Midwest ISO's classifications of demand response parties. Chapter 4 investigates the available opportunities at Alcoa's Warrick facility. Chapter 5 involves an in-depth discussion of the regulation service that Alcoa's Warrick facility can provide and the current interactions with Midwest ISO. Chapter 6 reviews future plans and expectations for Alcoa providing ancillary services into the market. Last, chapter 7, details the conclusion and recommendations of this paper.« less
Ad libitum or demand/semi-demand feeding versus scheduled interval feeding for preterm infants.
Tosh, K; McGuire, W
2006-07-19
Feeding preterm infants in response to their hunger and satiation cues (ad libitum or demand/semi demand) rather than at scheduled intervals might help in the establishment of independent oral feeding, increase nutrient intake and growth rates, and allow earlier hospital discharge. To assess the effect of a policy of feeding preterm infants on an ad libitum or demand/semi-demand basis versus feeding prescribed volumes at scheduled intervals on growth rates and the time to hospital discharge. We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2006), MEDLINE (1966 - March 2006), EMBASE (1980 - March 2006), CINAHL (1982 - March 2006), conference proceedings, and previous reviews. Randomised or quasi-randomised controlled trials (including cluster randomised trials) that compared a policy of feeding preterm infants on an ad libitum or demand/semi-demand basis versus feeding at scheduled intervals. The standard methods of the Cochrane Neonatal Review Group with separate evaluation of trial quality and data extraction by two review authors. The primary outcomes of interest were growth rates and age at hospital discharge. We found seven randomised controlled trials that compared ad libitum or demand/semi-demand regimes with scheduled interval regimes in preterm infants in the transition phase from intragastric tube to oral feeding. The trials were generally small and of variable methodological quality. The duration of the intervention and the duration of data collection and follow up in most of the trials is not likely to have allowed detection of measurable effects on growth. The single trial that assessed growth for longer than one week found that the rate of weight gain was lower in the ad libitum fed infants [mean difference -3.30 (95% confidence interval -6.2 to -0.4) grams per kilogram per day]. Two trials reported that feeding preterm infants using an ad libitum or demand/semi-demand feeding regime allowed earlier discharge from hospital, but the other trials did not confirm this finding. We were not able to undertake meta-analyses because of differences in study design and in the way the findings were reported. There are insufficient data at present to guide clinical practice. A large randomised controlled trial is needed to determine if ad libitum of demand/semi-demand feeding of preterm infants affects clinically important outcomes. This trial should focus on infants in the transition phase from intragastric tube to oral feeding and should be of sufficient duration to assess effects on growth and time to oral feeding and hospital discharge.
Dynamic goal states: adjusting cognitive control without conflict monitoring.
Scherbaum, Stefan; Dshemuchadse, Maja; Ruge, Hannes; Goschke, Thomas
2012-10-15
A central topic in the cognitive sciences is how cognitive control is adjusted flexibly to changing environmental demands at different time scales to produce goal-oriented behavior. According to an influential account, the context-sensitive recruitment of cognitive control is mediated by a specialized conflict monitoring process that registers current conflict and signals the demand for enhanced control in subsequent trials. This view has been immensely successful not least due to supporting evidence from neuroimaging studies suggesting that the conflict monitoring function is localized within the anterior cingulate cortex (ACC) which, in turn, signals the demand for enhanced control to the prefrontal cortex (PFC). In this article, we propose an alternative model of the adaptive regulation of cognitive control based on multistable goal attractor network dynamics and adjustments of cognitive control within a conflict trial. Without incorporation of an explicit conflict monitoring module, the model mirrors behavior in conflict tasks accounting for effects of response congruency, sequential conflict adaptation, and proportion of incongruent trials. Importantly, the model also mirrors frequency tagged EEG data indicating continuous conflict adaptation and suggests a reinterpretation of the correlation between ACC and the PFC BOLD data reported in previous imaging studies. Together, our simulation data propose an alternative interpretation of both behavioral data as well as imaging data that have previously been interpreted in favor of a specialized conflict monitoring process in the ACC. Copyright © 2012 Elsevier Inc. All rights reserved.
Control and Coordination of Frequency Responsive Residential Water Heaters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Williams, Tess L.; Kalsi, Karanjit; Elizondo, Marcelo A.
2016-07-31
Demand-side frequency control can complement traditional generator controls to maintain the stability of large electric systems in the face of rising uncertainty and variability associated with renewable energy resources. This paper presents a hierarchical frequency-based load control strategy that uses a supervisor to flexibly adjust control gains that a population of end-use loads respond to in a decentralized manner to help meet the NERC BAL-003-1 frequency response standard at both the area level and interconnection level. The load model is calibrated and used to model populations of frequency-responsive water heaters in a PowerWorld simulation of the U.S. Western Interconnection (WECC).more » The proposed design is implemented and demonstrated on physical water heaters in a laboratory setting. A significant fraction of the required frequency response in the WECC could be supplied by electric water heaters alone at penetration levels of less than 15%, while contributing to NERC requirements at the interconnection and area levels.« less
NASA Astrophysics Data System (ADS)
Wang, Qiming; Gossweiler, Gregory R.; Craig, Stephen L.; Zhao, Xuanhe
2014-09-01
Cephalopods can display dazzling patterns of colours by selectively contracting muscles to reversibly activate chromatophores - pigment-containing cells under their skins. Inspired by this novel colouring strategy found in nature, we design an electro-mechano-chemically responsive elastomer system that can exhibit a wide variety of fluorescent patterns under the control of electric fields. We covalently couple a stretchable elastomer with mechanochromic molecules, which emit strong fluorescent signals if sufficiently deformed. We then use electric fields to induce various patterns of large deformation on the elastomer surface, which displays versatile fluorescent patterns including lines, circles and letters on demand. Theoretical models are further constructed to predict the electrically induced fluorescent patterns and to guide the design of this class of elastomers and devices. The material and method open promising avenues for creating flexible devices in soft/wet environments that combine deformation, colorimetric and fluorescent response with topological and chemical changes in response to a single remote signal.
Horwood, A M; Turner, J E; Houston, S M; Riddell, P M
2001-11-01
A remote haploscopic photorefractor, designed for assessment of accommodation and convergence in infants and clinical groups, was used to determine heterophoria accommodative convergence/accommodation (AC/A) ratios in normal naïve adults. These were compared with conventional clinical measures. Twenty-one naïve subjects were used to compare occluded and unoccluded prism cover test responses with the remote haploscopic photorefractor using a text and picture target. Although luminance was generally low for both targets, binocular vergences were appropriate for target demand in both studies. Binocular accommodation showed greater lag for the highest target accommodative demand and the less demanding target. Occlusion not only reduced vergence response, but also frequently caused a marked reduction in accommodation, especially to the picture target. Normal mean AC/A values were found, but with wide variations between individual subjects. Although mean accommodation, vergence, and AC/A values were comparable with published data, we suggest that in these conditions using naïve subjects, accommodation is frequently inaccurate, especially on occlusion, without concomitant loss of vergence, at least at low light levels. Accommodative convergence may play a less important part in, and other cues contribute more to, the near reflex than has been previously suggested.
Electrospun nanofibers-mediated on-demand drug release.
Chen, Menglin; Li, Yan-Fang; Besenbacher, Flemming
2014-11-01
A living system has a complex and accurate regulation system with intelligent sensor-processor-effector components to enable the release of vital bioactive substances on demand at a specific site and time. Stimuli-responsive polymers mimic biological systems in a crude way where an external stimulus results in a change in conformation, solubility, or alternation of the hydrophilic/hydrophobic balance, and consequently release of a bioactive substance. Electrospinning is a straightforward and robust method to produce nanofibers with the potential to incorporate drugs in a simple, rapid, and reproducible process. This feature article emphasizes an emerging area using an electrospinning technique to generate biomimetic nanofibers as drug delivery devices that are responsive to different stimuli, such as temperature, pH, light, and electric/magnetic field for controlled release of therapeutic substances. Although at its infancy, the mimicry of these stimuli-responsive nanofibers to the function of the living systems includes both the fibrous structural feature and bio-regulation function as an on demand drug release depot. The electrospun nanofibers with extracellular matrix morphology intrinsically guide cellular drug uptake, which will be highly desired to translate the promise of drug delivery for the clinical success. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Pisanti, Renato; van der Doef, Margot; Maes, Stan; Lombardo, Caterina; Lazzari, David; Violani, Cristiano
2015-01-01
Aim: The main purpose of the present study was to extend the Job Demand Control Support (JDCS) model analyzing the direct and interactive role of occupational coping self-efficacy (OCSE) beliefs. Background: OCSE refers to an individual’s beliefs about their ability to cope with occupational stressors. The interplay between occupational stressors, job resources, and self-efficacy beliefs is poorly investigated. The present research attempts to address this gap. Design: Cross-sectional survey. Method: Questionnaire data from 1479 nurses (65% response) were analyzed. Hierarchical regression analyses were used to test the direct and moderating role of OCSE in conjunction with job demands (i.e., time pressure), and two job resources: job control (i.e., decision latitude and skill discretion) and social support (i.e., supervisor support and coworker support) in predicting psychological distress and well-being. Results: Our findings indicated that high demands, low job control, and low social support additively predicted the distress/well-being outcomes (job satisfaction, emotional exhaustion, depersonalization, psychological distress, and somatic complaints). Beyond the main effects, no significant interactive effects of demands, control, and support were found. OCSE accounted for an additional 1–4% of the variance in the outcomes, after controlling for the JDCS variables. In addition, the results indicate that OCSE buffers the association between low job control and the distress dimensions emotional exhaustion, depersonalization, and psychological distress. Low control was detrimental only for nurses with low OCSE. Conclusion: Our results suggest expanding the JDCS model incorporating individual characteristics such as OCSE beliefs, for predicting psychological distress and well-being. Limitations of the study and practical implications are discussed. PMID:26300827
Intravascular ATP and the regulation of blood flow and oxygen delivery in humans.
Crecelius, Anne R; Kirby, Brett S; Dinenno, Frank A
2015-01-01
Regulation of vascular tone is a complex response that integrates multiple signals that allow for blood flow and oxygen supply to match oxygen demand appropriately. Here, we discuss the potential role of intravascular adenosine triphosphate (ATP) as a primary factor in these responses and put forth the hypothesis that deficient ATP release contributes to impairments in vascular control exhibited in aged and diseased populations.
Demand Response and Energy Storage Integration Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, Ookie; Cheung, Kerry; Olsen, Daniel J.
2016-03-01
Demand response and energy storage resources present potentially important sources of bulk power system services that can aid in integrating variable renewable generation. While renewable integration studies have evaluated many of the challenges associated with deploying large amounts of variable wind and solar generation technologies, integration analyses have not yet fully incorporated demand response and energy storage resources. This report represents an initial effort in analyzing the potential integration value of demand response and energy storage, focusing on the western United States. It evaluates two major aspects of increased deployment of demand response and energy storage: (1) Their operational valuemore » in providing bulk power system services and (2) Market and regulatory issues, including potential barriers to deployment.« less
Demand Response and Energy Storage Integration Study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, Ookie; Cheung, Kerry
Demand response and energy storage resources present potentially important sources of bulk power system services that can aid in integrating variable renewable generation. While renewable integration studies have evaluated many of the challenges associated with deploying large amounts of variable wind and solar generation technologies, integration analyses have not yet fully incorporated demand response and energy storage resources. This report represents an initial effort in analyzing the potential integration value of demand response and energy storage, focusing on the western United States. It evaluates two major aspects of increased deployment of demand response and energy storage: (1) Their operational valuemore » in providing bulk power system services and (2) Market and regulatory issues, including potential barriers to deployment.« less
Uncertainty and operational considerations in mass prophylaxis workforce planning.
Hupert, Nathaniel; Xiong, Wei; King, Kathleen; Castorena, Michelle; Hawkins, Caitlin; Wu, Cindie; Muckstadt, John A
2009-12-01
The public health response to an influenza pandemic or other large-scale health emergency may include mass prophylaxis using multiple points of dispensing (PODs) to deliver countermeasures rapidly to affected populations. Computer models created to date to determine "optimal" staffing levels at PODs typically assume stable patient demand for service. The authors investigated POD function under dynamic and uncertain operational environments. The authors constructed a Monte Carlo simulation model of mass prophylaxis (the Dynamic POD Simulator, or D-PODS) to assess the consequences of nonstationary patient arrival patterns on POD function under a variety of POD layouts and staffing plans. Compared are the performance of a standard POD layout under steady-state and variable patient arrival rates that may mimic real-life variation in patient demand. To achieve similar performance, PODs functioning under nonstationary patient arrival rates require higher staffing levels than would be predicted using the assumption of stationary arrival rates. Furthermore, PODs may develop severe bottlenecks unless staffing levels vary over time to meet changing patient arrival patterns. Efficient POD networks therefore require command and control systems capable of dynamically adjusting intra- and inter-POD staff levels to meet demand. In addition, under real-world operating conditions of heightened uncertainty, fewer large PODs will require a smaller total staff than many small PODs to achieve comparable performance. Modeling environments that capture the effects of fundamental uncertainties in public health disasters are essential for the realistic evaluation of response mechanisms and policies. D-PODS quantifies POD operational efficiency under more realistic conditions than have been modeled previously. The authors' experiments demonstrate that effective POD staffing plans must be responsive to variation and uncertainty in POD arrival patterns. These experiments highlight the need for command and control systems to be created to manage emergency response successfully.
Demand curves for hypothetical cocaine in cocaine-dependent individuals.
Bruner, Natalie R; Johnson, Matthew W
2014-03-01
Drug purchasing tasks have been successfully used to examine demand for hypothetical consumption of abused drugs including heroin, nicotine, and alcohol. In these tasks, drug users make hypothetical choices whether to buy drugs, and if so, at what quantity, at various potential prices. These tasks allow for behavioral economic assessment of that drug's intensity of demand (preferred level of consumption at extremely low prices) and demand elasticity (sensitivity of consumption to price), among other metrics. However, a purchasing task for cocaine in cocaine-dependent individuals has not been investigated. This study examined a novel Cocaine Purchasing Task and the relation between resulting demand metrics and self-reported cocaine use data. Participants completed a questionnaire assessing hypothetical purchases of cocaine units at prices ranging from $0.01 to $1,000. Demand curves were generated from responses on the Cocaine Purchasing Task. Correlations compared metrics from the demand curve to measures of real-world cocaine use. Group and individual data were well modeled by a demand curve function. The validity of the Cocaine Purchasing Task was supported by a significant correlation between the demand curve metrics of demand intensity and O max (determined from Cocaine Purchasing Task data) and self-reported measures of cocaine use. Partial correlations revealed that after controlling for demand intensity, demand elasticity and the related measure, P max, were significantly correlated with real-world cocaine use. Results indicate that the Cocaine Purchasing Task produces orderly demand curve data, and that these data relate to real-world measures of cocaine use.
Lazarinis, Nikolaos; Jørgensen, Leif; Ekström, Tommy; Bjermer, Leif; Dahlén, Barbro; Pullerits, Teet; Hedlin, Gunilla; Carlsen, Kai-Håkon; Larsson, Kjell
2014-01-01
Background In mild asthma exercise-induced bronchoconstriction (EIB) is usually treated with inhaled short-acting β2 agonists (SABAs) on demand. Objective The hypothesis was that a combination of budesonide and formoterol on demand diminishes EIB equally to regular inhalation of budesonide and is more effective than terbutaline inhaled on demand. Methods Sixty-six patients with asthma (>12 years of age) with verified EIB were randomised to terbutaline (0.5 mg) on demand, regular budesonide (400 μg) and terbutaline (0.5 mg) on demand, or a combination of budesonide (200 μg) + formoterol (6 μg) on demand in a 6-week, double-blind, parallel-group study (ClinicalTrials.gov identifier: NCT00989833). The patients were instructed to perform three to four working sessions per week. The main outcome was EIB 24 h after the last dosing of study medication. Results After 6 weeks of treatment with regular budesonide or budesonide+formoterol on demand the maximum post-exercise forced expiratory volume in 1 s fall, 24 h after the last medication, was 6.6% (mean; 95% CI −10.3 to −3.0) and 5.4% (−8.9 to −1.8) smaller, respectively. This effect was superior to inhalation of terbutaline on demand (+1.5%; −2.1 to +5.1). The total budesonide dose was approximately 2.5 times lower in the budesonide+formoterol group than in the regular budesonide group. The need for extra medication was similar in the three groups. Conclusions The combination of budesonide and formoterol on demand improves asthma control by reducing EIB in the same order of magnitude as regular budesonide treatment despite a substantially lower total steroid dose. Both these treatments were superior to terbutaline on demand, which did not alter the bronchial response to exercise. The results question the recommendation of prescribing SABAs as the only treatment for EIB in mild asthma. PMID:24092567
Currently, nations around the globe are facing striking concerns regarding energy consumption. In the United States, we face increasing demands that will cause increasing fuel prices thus ultimately higher-energy cost. The future could be eased by reduce energy consumption ...
Public Libraries: Responding to Demand.
ERIC Educational Resources Information Center
Annichiarico, Mark; And Others
1993-01-01
Discussion of problems library wholesalers/distributors face trying to fulfill public libraries' needs while adjusting to a changing industry is based on responses by librarians to a survey on library jobbers. Increased services to libraries, electronic ordering, timeliness, stock management, and quality control are addressed; and a chart of…
NASA Astrophysics Data System (ADS)
Abad Lopez, Carlos Adrian
Current electricity infrastructure is being stressed from several directions -- high demand, unreliable supply, extreme weather conditions, accidents, among others. Infrastructure planners have, traditionally, focused on only the cost of the system; today, resilience and sustainability are increasingly becoming more important. In this dissertation, we develop computational tools for efficiently managing electricity resources to help create a more reliable and sustainable electrical grid. The tools we present in this work will help electric utilities coordinate demand to allow the smooth and large scale integration of renewable sources of energy into traditional grids, as well as provide infrastructure planners and operators in developing countries a framework for making informed planning and control decisions in the presence of uncertainty. Demand-side management is considered as the most viable solution for maintaining grid stability as generation from intermittent renewable sources increases. Demand-side management, particularly demand response (DR) programs that attempt to alter the energy consumption of customers either by using price-based incentives or up-front power interruption contracts, is more cost-effective and sustainable in addressing short-term supply-demand imbalances when compared with the alternative that involves increasing fossil fuel-based fast spinning reserves. An essential step in compensating participating customers and benchmarking the effectiveness of DR programs is to be able to independently detect the load reduction from observed meter data. Electric utilities implementing automated DR programs through direct load control switches are also interested in detecting the reduction in demand to efficiently pinpoint non-functioning devices to reduce maintenance costs. We develop sparse optimization methods for detecting a small change in the demand for electricity of a customer in response to a price change or signal from the utility, dynamic learning methods for scheduling the maintenance of direct load control switches whose operating state is not directly observable and can only be inferred from the metered electricity consumption, and machine learning methods for accurately forecasting the load of hundreds of thousands of residential, commercial and industrial customers. These algorithms have been implemented in the software system provided by AutoGrid, Inc., and this system has helped several utilities in the Pacific Northwest, Oklahoma, California and Texas, provide more reliable power to their customers at significantly reduced prices. Providing power to widely spread out communities in developing countries using the conventional power grid is not economically feasible. The most attractive alternative source of affordable energy for these communities is solar micro-grids. We discuss risk-aware robust methods to optimally size and operate solar micro-grids in the presence of uncertain demand and uncertain renewable generation. These algorithms help system operators to increase their revenue while making their systems more resilient to inclement weather conditions.
Selective and sustained attention in children with spina bifida myelomeningocele.
Caspersen, Ida Dyhr; Habekost, Thomas
2013-01-01
Spina bifida myelomeningocele (SBM) is a neural tube defect that has been related to deficits in several cognitive domains including attention. Attention function in children with SBM has often been studied using tasks that are confounded by complex motor demands or tasks that do not clearly distinguish perceptual from response-related components of attention. We used a verbal-report paradigm based on the Theory of Visual Attention (Bundesen, 1990) and a new continuous performance test, the Dual Attention to Response Task (Dockree et al., 2006), for measuring parameters of selective and sustained attention in 6 children with SBM and 18 healthy control children. The two tasks had minimal motor demands, were functionally specific and were sensitive to minor deficits. As a group, the children with SBM were significantly less efficient at filtering out irrelevant stimuli. Moreover, they exhibited frequent failures of sustained attention and response control in terms of omission errors, premature responses, and prolonged inhibition responses. All 6 children with SBM showed deficits in one or more parameters of attention; for example, three patients had elevated visual perception thresholds, but large individual variation was evident in their performance patterns, which highlights the relevance of an effective case-based assessment method in this patient group. Overall, the study demonstrates the strengths of a new testing approach for evaluating attention function in children with SBM.
Photosynthetic capacity regulation is uncoupled from nutrient limitation
NASA Astrophysics Data System (ADS)
Smith, N. G.; Keenan, T. F.; Prentice, I. C.; Wang, H.
2017-12-01
Ecosystem and Earth system models need information on leaf-level photosynthetic capacity, but to date typically rely on empirical estimates and an assumed dependence on nitrogen supply. Recent evidence suggests that leaf nitrogen is actively controlled though plant responses to photosynthetic demand. Here, we propose and test a theory of demand-driven coordination of photosynthetic processes, and use it to assess the relative roles of nutrient supply and photosynthetic demand. The theory captured 63% of observed variability in a global dataset of Rubisco carboxylation capacity (Vcmax; 3,939 values at 219 sites), suggesting that environmentally regulated biophysical costs and light availability are the first-order drivers of photosynthetic capacity. Leaf nitrogen, on the other hand, was a weak secondary driver of Vcmax, explaining less than 6% of additional observed variability. We conclude that leaf nutrient allocation is primarily driven by demand. Our theory offers a simple, robust strategy for dynamically predicting leaf-level photosynthetic capacity in global models.
Nemeth, Endre; Kovacs, Eniko; Racz, Kristof; Soltesz, Adam; Szigeti, Szabolcs; Kiss, Nikolett; Csikos, Gergely; Koritsanszky, Kinga B; Berzsenyi, Viktor; Trembickij, Gabor; Fabry, Szabolcs; Prohaszka, Zoltan; Merkely, Bela; Gal, Janos
2018-04-01
The aim of this study was to assess the influence of intraoperative cytokine adsorption on the perioperative vasoplegia, inflammatory response and outcome during orthotopic heart transplantation (OHT). Eighty-four OHT patients were separated into the cytokine adsorption (CA)-treated group or controls. Vasopressor demand, inflammatory response described by procalcitonin and C-reactive protein, and postoperative outcome were assessed performing propensity score matching. In the 16 matched pairs, the median noradrenaline requirement was significantly less in the CA-treated patients than in the controls on the first and second postoperative days (0.14 vs 0.3 μg*kg -1 *min -1 , P = .039 and 0.06 vs 0.32 μg*kg -1 *min -1 , P = .047). The inflammatory responses were similar in the two groups. There was a trend toward shorter length of mechanical ventilation and intensive care unit (ICU) stay in the CA-treated group compared to the controls. No difference in adverse events was observed between the two groups. However, the frequency of renal replacement therapy was significantly less in the CA-treated patients than in the controls (P = .031). Intraoperative CA treatment was associated with reduced vasopressor demand and less frequent renal replacement therapy with a favorable tendency in length of mechanical ventilation and ICU stay. CA treatment was not linked to higher rates of adverse events. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Nozawa, Takayuki; Sugiura, Motoaki; Yokoyama, Ryoichi; Ihara, Mizuki; Kotozaki, Yuka; Miyauchi, Carlos Makoto; Kanno, Akitake; Kawashima, Ryuta
2014-01-01
Can ongoing fMRI BOLD signals predict fluctuations in swiftness of a person's response to sporadic cognitive demands? This is an important issue because it clarifies whether intrinsic brain dynamics, for which spatio-temporal patterns are expressed as temporally coherent networks (TCNs), have effects not only on sensory or motor processes, but also on cognitive processes. Predictivity has been affirmed, although to a limited extent. Expecting a predictive effect on executive performance for a wider range of TCNs constituting the cingulo-opercular, fronto-parietal, and default mode networks, we conducted an fMRI study using a version of the color-word Stroop task that was specifically designed to put a higher load on executive control, with the aim of making its fluctuations more detectable. We explored the relationships between the fluctuations in ongoing pre-trial activity in TCNs and the task response time (RT). The results revealed the existence of TCNs in which fluctuations in activity several seconds before the onset of the trial predicted RT fluctuations for the subsequent trial. These TCNs were distributed in the cingulo-opercular and fronto-parietal networks, as well as in perceptual and motor networks. Our results suggest that intrinsic brain dynamics in these networks constitute "cognitive readiness," which plays an active role especially in situations where information for anticipatory attention control is unavailable. Fluctuations in these networks lead to fluctuations in executive control performance.
Interoperability of Demand Response Resources Demonstration in NY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wellington, Andre
2014-03-31
The Interoperability of Demand Response Resources Demonstration in NY (Interoperability Project) was awarded to Con Edison in 2009. The objective of the project was to develop and demonstrate methodologies to enhance the ability of customer sited Demand Response resources to integrate more effectively with electric delivery companies and regional transmission organizations.
A Longitudinal Test of the Demand–Control Model Using Specific Job Demands and Specific Job Control
van Vegchel, Natasja; Shimazu, Akihito; Schaufeli, Wilmar; Dormann, Christian
2010-01-01
Background Supportive studies of the demand–control (DC) model were more likely to measure specific demands combined with a corresponding aspect of control. Purpose A longitudinal test of Karasek’s (Adm Sci Q. 24:285–308, 1) job strain hypothesis including specific measures of job demands and job control, and both self-report and objectively recorded well-being. Method Job strain hypothesis was tested among 267 health care employees from a two-wave Dutch panel survey with a 2-year time lag. Results Significant demand/control interactions were found for mental and emotional demands, but not for physical demands. The association between job demands and job satisfaction was positive in case of high job control, whereas this association was negative in case of low job control. In addition, the relation between job demands and psychosomatic health symptoms/sickness absence was negative in case of high job control and positive in case of low control. Conclusion Longitudinal support was found for the core assumption of the DC model with specific measures of job demands and job control as well as self-report and objectively recorded well-being. PMID:20195810
Code of Federal Regulations, 2011 CFR
2011-07-01
... designee) of the creditor Labor Department agency shall send appropriate written demands to the debtor in... written demands at not more than 30-day intervals will normally be made unless a response to the first or second demand indicates that a further demand would be futile and the debtor's response does not require...
Code of Federal Regulations, 2010 CFR
2010-07-01
... designee) of the creditor Labor Department agency shall send appropriate written demands to the debtor in... written demands at not more than 30-day intervals will normally be made unless a response to the first or second demand indicates that a further demand would be futile and the debtor's response does not require...
USDA-ARS?s Scientific Manuscript database
Haemonchus contortus is a blood-sucking abomasal parasite of small ruminants that is responsible for major losses to producers worldwide. Resistance of this nematode to commercial anthelmintics has produced a demand for alternative control methods. Artemisia annua is the sole commercial source of ...
Environmental Stress and Biobehavioral Antecedents of Coronary Heart Disease.
ERIC Educational Resources Information Center
Krantz, David S.; And Others
1988-01-01
Provides an overview of research on the biobehavioral antecedents of coronary heart disease, including stressful occupational settings characterized by high demands and little control over the job, and the Type A pattern, particularly hostility and mode of anger expression (anger-in). Discusses research on physiologic responsiveness (reactivity)…
Implications for Veterinary Medical Education: Preprofessional and Professional Education.
ERIC Educational Resources Information Center
Vaughan, J. T.
1980-01-01
The need to boost the productivity curve for production of animal protein and the demand for specialists in all areas of animal agriculture are discussed. Legislative action and academic priorities must be initiated to assume the responsibility for the control of disease, promotion of health, and efficiency of production. (MLW)
NASA Astrophysics Data System (ADS)
Huang, Y.; Liu, B. Z.; Wang, K. Y.; Ai, X.
2017-12-01
In response to the new requirements of the operation mode of wind-storage combined system and demand side response for transmission network planning, this paper presents a joint planning of energy storage and transmission considering wind-storage combined system and demand side response. Firstly, the charge-discharge strategy of energy storage system equipped at the outlet of wind farm and demand side response strategy are analysed to achieve the best comprehensive benefits through the coordination of the two. Secondly, in the general transmission network planning model with wind power, both energy storage cost and demand side response cost are added to the objective function. Not only energy storage operation constraints and but also demand side response constraints are introduced into the constraint condition. Based on the classical formulation of TEP, a new formulation is developed considering the simultaneous addition of the charge-discharge strategy of energy storage system equipped at the outlet of the wind farm and demand side response strategy, which belongs to a typical mixed integer linear programming model that can be solved by mature optimization software. The case study based on the Garver-6 bus system shows that the validity of the proposed model is verified by comparison with general transmission network planning model. Furthermore, the results demonstrate that the joint planning model can gain more economic benefits through setting up different cases.
Renewable Energy Resources Portfolio Optimization in the Presence of Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Behboodi, Sahand; Chassin, David P.; Crawford, Curran
In this paper we introduce a simple cost model of renewable integration and demand response that can be used to determine the optimal mix of generation and demand response resources. The model includes production cost, demand elasticity, uncertainty costs, capacity expansion costs, retirement and mothballing costs, and wind variability impacts to determine the hourly cost and revenue of electricity delivery. The model is tested on the 2024 planning case for British Columbia and we find that cost is minimized with about 31% renewable generation. We also find that demand responsive does not have a significant impact on cost at themore » hourly level. The results suggest that the optimal level of renewable resource is not sensitive to a carbon tax or demand elasticity, but it is highly sensitive to the renewable resource installation cost.« less
Wetherell, Mark A; Atherton, Katie; Grainger, Jessica; Brosnan, Robert; Scholey, Andrew B
2012-03-01
Cannabis and 3,4-methylenedioxymethamphetamine (MDMA) use is associated with psychobiological and neurocognitive deficits. Assessments of the latter typically include tests of memory and everyday cognitive functioning. However, to date, little attention has been paid to effects of drug use on psychological stress reactivity. We report three studies examining the effects of recreational use of cannabis and MDMA on mood and psychological responses to multitasking using a cognitively demanding laboratory stressor that provides an analogue for everyday situations involving responses to multiple stimuli. The effects of the multitasking framework on mood and perceived workload were assessed in cannabis (N=25), younger (N=18) and older (N=20) MDMA users and compared with non-target drug controls. Compared with respective control groups, cannabis users became less alert and content, and both MDMA groups became less calm following acute stress. Unexpectedly, the stressor increased ratings of calm in cannabis users. Users also scored higher than their controls with respect to ratings of resources needed to complete the multitasking framework. These findings show, for the first time, that recreational use of cannabis and MDMA, beyond the period of intoxication, can negatively influence psychological responses to a multitasking stressor, and this may have implications for real-life situations which place high demands on cognitive resources. Copyright © 2012 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Wang, Kunpeng; Tan, Handong
2017-11-01
Controlled-source audio-frequency magnetotellurics (CSAMT) has developed rapidly in recent years and are widely used in the area of mineral and oil resource exploration as well as other fields. The current theory, numerical simulation, and inversion research are based on the assumption that the underground media have resistivity isotropy. However a large number of rock and mineral physical property tests show the resistivity of underground media is generally anisotropic. With the increasing application of CSAMT, the demand for probe accuracy of practical exploration to complex targets continues to increase. The question of how to evaluate the influence of anisotropic resistivity to CSAMT response is becoming important. To meet the demand for CSAMT response research of resistivity anisotropic media, this paper examines the CSAMT electric equations, derives and realizes a three-dimensional (3D) staggered-grid finite difference numerical simulation method of CSAMT resistivity axial anisotropy. Through building a two-dimensional (2D) resistivity anisotropy geoelectric model, we validate the 3D computation result by comparing it to the result of controlled-source electromagnetic method (CSEM) resistivity anisotropy 2D finite element program. Through simulating a 3D resistivity axial anisotropy geoelectric model, we compare and analyze the responses of equatorial configuration, axial configuration, two oblique sources and tensor source. The research shows that the tensor source is suitable for CSAMT to recognize the anisotropic effect of underground structure.
Reduced-Order Models for Load Management in the Power Grid
NASA Astrophysics Data System (ADS)
Alizadeh, Mahnoosh
In recent years, considerable research efforts have been directed towards designing control schemes that can leverage the inherent flexibility of electricity demand that is not tapped into in today's electricity markets. It is expected that these control schemes will be carried out by for-profit entities referred to as aggregators that operate at the edge of the power grid network. While the aggregator control problem is receiving much attention, more high-level questions of how these aggregators should plan their market participation, interact with the main grid and with each other, remain rather understudied. Answering these questions requires a large-scale model for the aggregate flexibility that can be harnessed from the a population of customers, particularly for residences and small businesses. The contribution of this thesis towards this goal is divided into three parts: In Chapter 3, a reduced-order model for a large population of heterogeneous appliances is provided by clustering load profiles that share similar degrees of freedom together. The use of such reduced-order model for system planning and optimal market decision making requires a foresighted approximation of the number of appliances that will join each cluster. Thus, Chapter 4 provides a systematic framework to generate such forecasts for the case of Electric Vehicles, based on real-world battery charging data. While these two chapters set aside the economic side that is naturally involved with participation in demand response programs and mainly focus on the control problem, Chapter 5 is dedicated to the study of optimal pricing mechanisms in order to recruit heterogeneous customers in a demand response program in which an aggregator can directly manage their appliances' load under their specified preferences. Prices are proportional to the wholesale market savings that can result from each recruitment event.
Foresee: A user-centric home energy management system for energy efficiency and demand response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin, Xin; Baker, Kyri A.; Christensen, Dane T.
This paper presents foresee, a user-centric home energy management system that can help optimize how a home operates to concurrently meet users' needs, achieve energy efficiency and commensurate utility cost savings, and reliably deliver grid services based on utility signals. Foresee is built on a multiobjective model predictive control framework, wherein the objectives consist of energy cost, thermal comfort, user convenience, and carbon emission. Foresee learns user preferences on different objectives and acts on their behalf to operate building equipment, such as home appliances, photovoltaic systems, and battery storage. In this work, machine-learning algorithms were used to derive data-driven appliancemore » models and usage patterns to predict the home's future energy consumption. This approach enables highly accurate predictions of comfort needs, energy costs, environmental impacts, and grid service availability. Simulation studies were performed on field data from a residential building stock data set collected in the Pacific Northwest. Results indicated that foresee generated up to 7.6% whole-home energy savings without requiring substantial behavioral changes. When responding to demand response events, foresee was able to provide load forecasts upon receipt of event notifications and delivered the committed demand response services with 10% or fewer errors. Foresee fully utilized the potential of the battery storage and controllable building loads and delivered up to 7.0-kW load reduction and 13.5-kW load increase. As a result, these benefits are provided while maintaining the occupants' thermal comfort or convenience in using their appliances.« less
Foresee: A user-centric home energy management system for energy efficiency and demand response
Jin, Xin; Baker, Kyri A.; Christensen, Dane T.; ...
2017-08-23
This paper presents foresee, a user-centric home energy management system that can help optimize how a home operates to concurrently meet users' needs, achieve energy efficiency and commensurate utility cost savings, and reliably deliver grid services based on utility signals. Foresee is built on a multiobjective model predictive control framework, wherein the objectives consist of energy cost, thermal comfort, user convenience, and carbon emission. Foresee learns user preferences on different objectives and acts on their behalf to operate building equipment, such as home appliances, photovoltaic systems, and battery storage. In this work, machine-learning algorithms were used to derive data-driven appliancemore » models and usage patterns to predict the home's future energy consumption. This approach enables highly accurate predictions of comfort needs, energy costs, environmental impacts, and grid service availability. Simulation studies were performed on field data from a residential building stock data set collected in the Pacific Northwest. Results indicated that foresee generated up to 7.6% whole-home energy savings without requiring substantial behavioral changes. When responding to demand response events, foresee was able to provide load forecasts upon receipt of event notifications and delivered the committed demand response services with 10% or fewer errors. Foresee fully utilized the potential of the battery storage and controllable building loads and delivered up to 7.0-kW load reduction and 13.5-kW load increase. As a result, these benefits are provided while maintaining the occupants' thermal comfort or convenience in using their appliances.« less
Leue, Anja; Weber, Bernd; Beauducel, André
2014-01-01
Conflict monitoring is a process of stimulus evaluation and a pre-requisite for subsequent recruitment of cognitive control and behavioral adaptations. This study investigated how experimentally manipulated working-memory-related cognitive demand and aversive reinforcement modulate individual differences of conflict monitoring intensity and behavioral adjustments. Individual differences were assessed by means of an anxiety-related trait dimension (trait-BIS) and by means of reasoning abilities—a core determinant of intelligence. Moreover, we investigated the special role of verbal reasoning ability and figural reasoning ability for the modulation of the conflict monitoring intensity. Ninety participants performed a go/nogo task with four conditions each comprising a combination of low vs. high working-memory-related cognitive demand and low vs. high aversive reinforcement. No effect of aversive reinforcement was observed for the N2 amplitude. The fronto-central nogo N2 amplitude was more pronounced for high demand vs. low demand suggesting that cognitive demand served as an aversive costly event. Higher total reasoning abilities were associated with more intense conflict monitoring and shorter response times with increasing aversive reinforcement (defined as verbal error-feedback vs. monetary loss). Individuals with higher trait-BIS scores demonstrated a more intense conflict monitoring even in conditions with low aversive reinforcement and also a more cautious responding (i.e., response times slowing) with increasing aversive reinforcement indicating a focus on negative feedback prevention. The findings provide evidence for the conflict monitoring theory and suggest that working-memory-related demand overrules the impact of aversive reinforcement on conflict monitoring intensity. Reasoning abilities and anxiety-related traits go along with an intensification of conflict monitoring but differences in the flexibility of behavioral adjustment. PMID:24782739
The behavioral economics of driving after drinking among college drinkers.
Teeters, Jenni B; Murphy, James G
2015-05-01
Driving after drinking (DAD) among college students is a significant public health concern, yet little is known about specific theoretical risk factors for DAD, beyond drinking level, among college student drinkers. This study had the following aims: (i) to examine the associations between elevated alcohol demand and DAD, (ii) to determine whether demand decreases in response to a hypothetical driving scenario, (iii) to determine whether drivers who report DAD in the past 3 months would show less of a reduction in demand in response to the hypothetical driving scenario, and (iv) to determine whether delayed reward discounting (DRD) is associated with DAD. Participants were 419 college students who reported at least 1 day of past-month alcohol use. Participants completed 2 alcohol purchase tasks (APTs) that assessed hypothetical alcohol consumption across 17 drink prices with and without a driving scenario, a delay-discounting task, and a series of questions regarding DAD. In logistic regression models that controlled for drinking level, demographics, and sensation seeking, participants reporting higher demand intensity (95% confidence interval [95% CI] [1.04, 2.34]), breakpoint (95% CI [1.23, 2.28]), Omax (95% CI [1.03, 1.53]), and lower elasticity (95% CI [0.15, 1.02]) were more likely to report DAD. Additionally, in analyses of covariance, DAD(+) participants exhibited significantly less of a reduction in demand between the standard and the driving APT (intensity, p < 0.01, breakpoint, p = 0.05, and Omax , p < 0.01). A binary logistic regression model with identical covariates revealed that DRD is not associated with DAD. DAD is associated with elevated/inelastic demand and less sensitivity to a hypothetical driving scenario. Drinkers with elevated demand should be prioritized for DAD intervention efforts. Copyright © 2015 by the Research Society on Alcoholism.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Geller, Drew Adam; Backhaus, Scott N.
Control of consumer electrical devices for providing electrical grid services is expanding in both the scope and the diversity of loads that are engaged in control, but there are few experimentally-based models of these devices suitable for control designs and for assessing the cost of control. A laboratory-scale test system is developed to experimentally evaluate the use of a simple window-mount air conditioner for electrical grid regulation services. The experimental test bed is a single, isolated air conditioner embedded in a test system that both emulates the thermodynamics of an air conditioned room and also isolates the air conditioner frommore » the real-world external environmental and human variables that perturb the careful measurements required to capture a model that fully characterizes both the control response functions and the cost of control. The control response functions and cost of control are measured using harmonic perturbation of the temperature set point and a test protocol that further isolates the air conditioner from low frequency environmental variability.« less
Cognitive control predicted by color vision, and vice versa.
Colzato, Lorenza S; Sellaro, Roberta; Hulka, Lea M; Quednow, Boris B; Hommel, Bernhard
2014-09-01
One of the most important functions of cognitive control is to continuously adapt cognitive processes to changing and often conflicting demands of the environment. Dopamine (DA) has been suggested to play a key role in the signaling and resolution of such response conflict. Given that DA is found in high concentration in the retina, color vision discrimination has been suggested as an index of DA functioning and in particular blue-yellow color vision impairment (CVI) has been used to indicate a central hypodopaminergic state. We used color discrimination (indexed by the total color distance score; TCDS) to predict individual differences in the cognitive control of response conflict, as reflected by conflict-resolution efficiency in an auditory Simon task. As expected, participants showing better color discrimination were more efficient in resolving response conflict. Interestingly, participants showing a blue-yellow CVI were associated with less efficiency in handling response conflict. Our findings indicate that color vision discrimination might represent a promising predictor of cognitive controlability in healthy individuals. Copyright © 2014 Elsevier Ltd. All rights reserved.
Nelson, Timothy D.; Nelson, Jennifer Mize; James, Tiffany D.; Clark, Caron A.C.; Kidwell, Katherine M.; Espy, Kimberly Andrews
2017-01-01
The transition to elementary school is accompanied by increasing demands for children to regulate their attention and behavior within the classroom setting. Executive control (EC) may be critical for meeting these demands; however, few studies have rigorously examined the association between EC and observed classroom behavior. This study examined EC in preschool (age 5 years, 3 months) as a predictor of classroom learning engagement behaviors in first grade, using a battery of performance-based EC tasks and live classroom observations in a longitudinal sample of 313 children. Multilevel modeling results indicated that stronger EC predicted more focused engagement and fewer task management and competing responses, controlling for socioeconomic status, child sex, and age at observations. Results suggest that early EC may support subsequent classroom engagement behaviors that are critical for successful transition to elementary school and long-term learning trajectories. PMID:28358540
Calatayud, Joaquin; Jakobsen, Markus D; Sundstrup, Emil; Casaña, Jose; Andersen, Lars L
2015-12-01
Regular physical activity is important for longevity and health, but knowledge about the optimal dose of physical activity for maintaining good work ability is unknown. This study investigates the association between intensity and duration of physical activity during leisure time and work ability in relation to physical demands of the job. From the 2010 round of the Danish Work Environment Cohort Study, currently employed wage earners with physically demanding work (n = 2952) replied to questions about work, lifestyle and health. Excellent (100 points), very good (75 points), good (50 points), fair (25 points) and poor (0 points) work ability in relation to the physical demands of the job was experienced by 18%, 40%, 30%, 10% and 2% of the respondents, respectively. General linear models that controlled for gender, age, physical and psychosocial work factors, lifestyle and chronic disease showed that the duration of high-intensity physical activity during leisure was positively associated with work ability, in a dose-response fashion (p < 0.001). Those performing ⩾ 5 hours of high-intensity physical activity per week had on average 8 points higher work ability than those not performing such activities. The duration of low-intensity leisure-time physical activity was not associated with work ability (p = 0.5668). The duration of high-intensity physical activity during leisure time is associated in a dose-response fashion with work ability, in workers with physically demanding jobs. © 2015 the Nordic Societies of Public Health.
Reinforcement learning techniques for controlling resources in power networks
NASA Astrophysics Data System (ADS)
Kowli, Anupama Sunil
As power grids transition towards increased reliance on renewable generation, energy storage and demand response resources, an effective control architecture is required to harness the full functionalities of these resources. There is a critical need for control techniques that recognize the unique characteristics of the different resources and exploit the flexibility afforded by them to provide ancillary services to the grid. The work presented in this dissertation addresses these needs. Specifically, new algorithms are proposed, which allow control synthesis in settings wherein the precise distribution of the uncertainty and its temporal statistics are not known. These algorithms are based on recent developments in Markov decision theory, approximate dynamic programming and reinforcement learning. They impose minimal assumptions on the system model and allow the control to be "learned" based on the actual dynamics of the system. Furthermore, they can accommodate complex constraints such as capacity and ramping limits on generation resources, state-of-charge constraints on storage resources, comfort-related limitations on demand response resources and power flow limits on transmission lines. Numerical studies demonstrating applications of these algorithms to practical control problems in power systems are discussed. Results demonstrate how the proposed control algorithms can be used to improve the performance and reduce the computational complexity of the economic dispatch mechanism in a power network. We argue that the proposed algorithms are eminently suitable to develop operational decision-making tools for large power grids with many resources and many sources of uncertainty.
Industrial Scale Energy Systems Integration; NREL (National Renewable Energy Laboratory)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ruth, Mark
2015-07-28
The industrial sector consumes 25% of the total energy in the U.S. and produces 18% of the greenhouse gas (GHG) emissions. Energy Systems Integration (ESI) opportunities can reduce those values and increase the profitability of that sector. This presentation outlines several options. Combined heat and power (CHP) is an option that is available today for many applications. In some cases, it can be extended to trigeneration by adding absorbtion cooling. Demand response is another option in use by the industrial sector - in 2012, industry provided 47% of demand response capacity. A longer term option that combines the benefits ofmore » CHP with those of demand response is hybrid energy systems (HESs). Two possible HESs are described and development implications discussed. extended to trigeneration by adding absorbtion cooling. Demand response is another option in use by the industrial sector - in 2012, industry provided 47% of demand response capacity. A longer term option that combines the benefits of CHP with those of demand response is hybrid energy systems (HESs). Two possible HESs are described and development implications discussed.« less
Flynn, Niamh; James, Jack E
2009-05-01
The hypothesis that work control has beneficial effects on well-being is the basis of the widely applied, yet inconsistently supported, Job Demand Control (JDC) Model [Karasek, R.A., 1979. Job demands, job decision latitude and mental strain: Implications for job redesign. Adm. Sci. Q. 24, 285-308.; Karasek, R., Theorell, T., 1990. Healthy Work: Stress, Productivity, and the Reconstruction of Working Life. Basic Books, Oxford]. The model was tested in an experiment (N=60) using a cognitive stressor paradigm that sought to prevent confounding between demand and control. High-demand was found to be associated with deleterious effects on physiological, subjective, and performance outcomes. In contrast, few main effects were found for control. Evidence for the buffer interpretation of the JDC Model was limited to a significant demand-control interaction for performance accuracy, whereas substantial support was found for the strain interpretation of the model [van der Doef, M., Maes, S., 1998. The job demand-control(-support) model and physical health outcomes: A review of the strain and buffer hypotheses. Psychol. Health 13, 909-936., van der Doef, M., Maes, S., 1999. The Job Demand-Control(-Support) model and psychological well-being: A review of 20 years of empirical research. Work Stress 13, 87-114]. Manipulation checks revealed that objective control altered perceptions of control but not perceptions of demand. It is suggested that beneficial effects of work-related control are unlikely to occur in the absence of reductions in perceived demand. Thus, contrary to the propositions of Karasek and colleagues, demand and control do not appear to be independent factors.
Development of robust building energy demand-side control strategy under uncertainty
NASA Astrophysics Data System (ADS)
Kim, Sean Hay
The potential of carbon emission regulations applied to an individual building will encourage building owners to purchase utility-provided green power or to employ onsite renewable energy generation. As both cases are based on intermittent renewable energy sources, demand side control is a fundamental precondition for maximizing the effectiveness of using renewable energy sources. Such control leads to a reduction in peak demand and/or in energy demand variability, therefore, such reduction in the demand profile eventually enhances the efficiency of an erratic supply of renewable energy. The combined operation of active thermal energy storage and passive building thermal mass has shown substantial improvement in demand-side control performance when compared to current state-of-the-art demand-side control measures. Specifically, "model-based" optimal control for this operation has the potential to significantly increase performance and bring economic advantages. However, due to the uncertainty in certain operating conditions in the field its control effectiveness could be diminished and/or seriously damaged, which results in poor performance. This dissertation pursues improvements of current demand-side controls under uncertainty by proposing a robust supervisory demand-side control strategy that is designed to be immune from uncertainty and perform consistently under uncertain conditions. Uniqueness and superiority of the proposed robust demand-side controls are found as below: a. It is developed based on fundamental studies about uncertainty and a systematic approach to uncertainty analysis. b. It reduces variability of performance under varied conditions, and thus avoids the worst case scenario. c. It is reactive in cases of critical "discrepancies" observed caused by the unpredictable uncertainty that typically scenario uncertainty imposes, and thus it increases control efficiency. This is obtainable by means of i) multi-source composition of weather forecasts including both historical archive and online sources and ii) adaptive Multiple model-based controls (MMC) to mitigate detrimental impacts of varying scenario uncertainties. The proposed robust demand-side control strategy verifies its outstanding demand-side control performance in varied and non-indigenous conditions compared to the existing control strategies including deterministic optimal controls. This result reemphasizes importance of the demand-side control for a building in the global carbon economy. It also demonstrates a capability of risk management of the proposed robust demand-side controls in highly uncertain situations, which eventually attains the maximum benefit in both theoretical and practical perspectives.
Speech-based E-mail and driver behavior: effects of an in-vehicle message system interface.
Jamson, A Hamish; Westerman, Stephen J; Hockey, G Robert J; Carsten, Oliver M J
2004-01-01
As mobile office technology becomes more advanced, drivers have increased opportunity to process information "on the move." Although speech-based interfaces can minimize direct interference with driving, the cognitive demands associated with such systems may still cause distraction. We studied the effects on driving performance of an in-vehicle simulated "E-mail" message system; E-mails were either system controlled or driver controlled. A high-fidelity, fixed-base driving simulator was used to test 19 participants on a car-following task. Virtual traffic scenarios varying in driving demand. Drivers compensated for the secondary task by adopting longer headways but showed reduced anticipation of braking requirements and shorter time to collision. Drivers were also less reactive when processing E-mails, demonstrated by a reduction in steering wheel inputs. In most circumstances, there were advantages in providing drivers with control over when E-mails were opened. However, during periods without E-mail interaction in demanding traffic scenarios, drivers showed reduced braking anticipation. This may be a result of increased cognitive costs associated with the decision making process when using a driver-controlled interface when the task of scheduling E-mail acceptance is added to those of driving and E-mail response. Actual or potential applications of this research include the design of speech-based in-vehicle messaging systems.
Vaurio, Rebecca G; Simmonds, Daniel J; Mostofsky, Stewart H
2009-10-01
One of the most consistent findings in children with ADHD is increased moment-to-moment variability in reaction time (RT). The source of increased RT variability can be examined using ex-Gaussian analyses that divide variability into normal and exponential components and Fast Fourier transform (FFT) that allow for detailed examination of the frequency of responses in the exponential distribution. Prior studies of ADHD using these methods have produced variable results, potentially related to differences in task demand. The present study sought to examine the profile of RT variability in ADHD using two Go/No-go tasks with differing levels of cognitive demand. A total of 140 children (57 with ADHD and 83 typically developing controls), ages 8-13 years, completed both a "simple" Go/No-go task and a more "complex" Go/No-go task with increased working memory load. Repeated measures ANOVA of ex-Gaussian functions revealed for both tasks children with ADHD demonstrated increased variability in both the normal/Gaussian (significantly elevated sigma) and the exponential (significantly elevated tau) components. In contrast, FFT analysis of the exponential component revealed a significant task x diagnosis interaction, such that infrequent slow responses in ADHD differed depending on task demand (i.e., for the simple task, increased power in the 0.027-0.074 Hz frequency band; for the complex task, decreased power in the 0.074-0.202 Hz band). The ex-Gaussian findings revealing increased variability in both the normal (sigma) and exponential (tau) components for the ADHD group, suggest that both impaired response preparation and infrequent "lapses in attention" contribute to increased variability in ADHD. FFT analyses reveal that the periodicity of intermittent lapses of attention in ADHD varies with task demand. The findings provide further support for intra-individual variability as a candidate intermediate endophenotype of ADHD.
Sustainable IT and IT for Sustainability
NASA Astrophysics Data System (ADS)
Liu, Zhenhua
Energy and sustainability have become one of the most critical issues of our generation. While the abundant potential of renewable energy such as solar and wind provides a real opportunity for sustainability, their intermittency and uncertainty present a daunting operating challenge. This thesis aims to develop analytical models, deployable algorithms, and real systems to enable efficient integration of renewable energy into complex distributed systems with limited information. The first thrust of the thesis is to make IT systems more sustainable by facilitating the integration of renewable energy into these systems. IT represents the fastest growing sectors in energy usage and greenhouse gas pollution. Over the last decade there are dramatic improvements in the energy efficiency of IT systems, but the efficiency improvements do not necessarily lead to reduction in energy consumption because more servers are demanded. Further, little effort has been put in making IT more sustainable, and most of the improvements are from improved "engineering" rather than improved "algorithms". In contrast, my work focuses on developing algorithms with rigorous theoretical analysis that improve the sustainability of IT. In particular, this thesis seeks to exploit the flexibilities of cloud workloads both (i) in time by scheduling delay-tolerant workloads and (ii) in space by routing requests to geographically diverse data centers. These opportunities allow data centers to adaptively respond to renewable availability, varying cooling efficiency, and fluctuating energy prices, while still meeting performance requirements. The design of the enabling algorithms is however very challenging because of limited information, non-smooth objective functions and the need for distributed control. Novel distributed algorithms are developed with theoretically provable guarantees to enable the "follow the renewables" routing. Moving from theory to practice, I helped HP design and implement industry's first Net-zero Energy Data Center. The second thrust of this thesis is to use IT systems to improve the sustainability and efficiency of our energy infrastructure through data center demand response. The main challenges as we integrate more renewable sources to the existing power grid come from the fluctuation and unpredictability of renewable generation. Although energy storage and reserves can potentially solve the issues, they are very costly. One promising alternative is to make the cloud data centers demand responsive. The potential of such an approach is huge. To realize this potential, we need adaptive and distributed control of cloud data centers and new electricity market designs for distributed electricity resources. My work is progressing in both directions. In particular, I have designed online algorithms with theoretically guaranteed performance for data center operators to deal with uncertainties under popular demand response programs. Based on local control rules of customers, I have further designed new pricing schemes for demand response to align the interests of customers, utility companies, and the society to improve social welfare.
NASA Technical Reports Server (NTRS)
Sellers, J. F.
1973-01-01
The transient performance of two concepts for control of vertical takeoff aircraft remote lift fans is analyzed and discussed. Both concepts employ flow transfer between pairs of lift fans located in separate parts of the aircraft in order to obtain attitude control moments for hover and low-speed flight. The results presented are from a digital computer, dynamic analysis of the YJ97/LF460 remote drive turbofan. The transient responses of the two systems are presented for step demands in lift and moment.
Demand Curves for Hypothetical Cocaine in Cocaine-Dependent Individuals
Bruner, Natalie R.; Johnson, Matthew W.
2013-01-01
Rationale Drug purchasing tasks have been successfully used to examine demand for hypothetical consumption of abused drugs including heroin, nicotine, and alcohol. In these tasks drug users make hypothetical choices whether to buy drugs, and if so, at what quantity, at various potential prices. These tasks allow for behavioral economic assessment of that drug's intensity of demand (preferred level of consumption at extremely low prices) and demand elasticity (sensitivity of consumption to price), among other metrics. However, a purchasing task for cocaine in cocaine-dependent individuals has not been investigated. Objectives This study examined a novel Cocaine Purchasing Task and the relation between resulting demand metrics and self-reported cocaine use data. Methods Participants completed a questionnaire assessing hypothetical purchases of cocaine units at prices ranging from $0.01 to $1,000. Demand curves were generated from responses on the Cocaine Purchasing Task. Correlations compared metrics from the demand curve to measures of real-world cocaine use. Results Group and individual data were well modeled by a demand curve function. The validity of the Cocaine Purchasing Task was supported by a significant correlation between the demand curve metrics of demand intensity and Omax (determined from Cocaine Purchasing Task data) and self-reported measures of cocaine use. Partial correlations revealed that after controlling for demand intensity, demand elasticity and the related measure, Pmax, were significantly correlated with real-world cocaine use. Conclusions Results indicate that the Cocaine Purchasing Task produces orderly demand curve data, and that these data relate to real-world measures of cocaine use. PMID:24217899
Tobacco excise and declining tobacco consumption: the case of Papua New Guinea.
Chapman, S; Richardson, J
1990-01-01
Excise elasticities of demand for non-cigarette tobacco and cigarettes were calculated for Papua New Guinea for the 14 years 1973-86. Respectively, these were -0.50 and -0.71. This means that 10 percent increases in cigarette and non-cigarette tobacco excise are associated with an estimated 7.1 percent fall in demand for cigarettes and a 5 percent decrease in the demand for tobacco. As tax (excise) elasticities would normally be significantly smaller than price elasticities, these results imply that the consumption of cigarettes and tobacco in Papua New Guinea are more responsive to prices than in the United States and other Western countries. The level of excise is therefore an important and practical instrument for the control of consumption. These elasticities appear to be the first reported for a developing country. It is suggested that if they are indicative of consumer behavior in lower income countries then increasing tobacco and cigarette excise should be considered as an important strategy for the control of smoking in these countries which, because of their large populations, are huge markets for tobacco products and thus major targets for tobacco control measures. PMID:2327528
The Role of Demand Response in Reducing Water-Related Power Plant Vulnerabilities
NASA Astrophysics Data System (ADS)
Macknick, J.; Brinkman, G.; Zhou, E.; O'Connell, M.; Newmark, R. L.; Miara, A.; Cohen, S. M.
2015-12-01
The electric sector depends on readily available water supplies for reliable and efficient operation. Elevated water temperatures or low water levels can trigger regulatory or plant-level decisions to curtail power generation, which can affect system cost and reliability. In the past decade, dozens of power plants in the U.S. have curtailed generation due to water temperatures and water shortages. Curtailments occur during the summer, when temperatures are highest and there is greatest demand for electricity. Climate change could alter the availability and temperature of water resources, exacerbating these issues. Constructing alternative cooling systems to address vulnerabilities can be capital intensive and can also affect power plant efficiencies. Demand response programs are being implemented by electric system planners and operators to reduce and shift electricity demands from peak usage periods to other times of the day. Demand response programs can also play a role in reducing water-related power sector vulnerabilities during summer months. Traditionally, production cost modeling and demand response analyses do not include water resources. In this effort, we integrate an electricity production cost modeling framework with water-related impacts on power plants in a test system to evaluate the impacts of demand response measures on power system costs and reliability. Specifically, we i) quantify the cost and reliability implications of incorporating water resources into production cost modeling, ii) evaluate the impacts of demand response measures on reducing system costs and vulnerabilities, and iii) consider sensitivity analyses with cooling systems to highlight a range of potential benefits of demand response measures. Impacts from climate change on power plant performance and water resources are discussed. Results provide key insights to policymakers and practitioners for reducing water-related power plant vulnerabilities via lower cost methods.
Luiselli, J K
2000-07-01
A 3-year-old child with multiple medical disorders and chronic food refusal was treated successfully using a program that incorporated antecedent control procedures combined with positive reinforcement. The antecedent manipulations included visual cueing of a criterion number of self-feeding responses that were required during meals to receive reinforcement and a gradual increase in the imposed criterion (demand fading) that was based on improved frequency of oral consumption. As evaluated in a changing criterion design, the child learned to feed himself as an outcome of treatment. One year following intervention, he was consuming a variety of foods and had gained weight. Advantages of antecedent control methods for the treatment of chronic food refusal are discussed.
Spatial effects, sampling errors, and task specialization in the honey bee.
Johnson, B R
2010-05-01
Task allocation patterns should depend on the spatial distribution of work within the nest, variation in task demand, and the movement patterns of workers, however, relatively little research has focused on these topics. This study uses a spatially explicit agent based model to determine whether such factors alone can generate biases in task performance at the individual level in the honey bees, Apis mellifera. Specialization (bias in task performance) is shown to result from strong sampling error due to localized task demand, relatively slow moving workers relative to nest size, and strong spatial variation in task demand. To date, specialization has been primarily interpreted with the response threshold concept, which is focused on intrinsic (typically genotypic) differences between workers. Response threshold variation and sampling error due to spatial effects are not mutually exclusive, however, and this study suggests that both contribute to patterns of task bias at the individual level. While spatial effects are strong enough to explain some documented cases of specialization; they are relatively short term and not explanatory for long term cases of specialization. In general, this study suggests that the spatial layout of tasks and fluctuations in their demand must be explicitly controlled for in studies focused on identifying genotypic specialists.
Bifurcation Analysis of a DC-DC Bidirectional Power Converter Operating with Constant Power Loads
NASA Astrophysics Data System (ADS)
Cristiano, Rony; Pagano, Daniel J.; Benadero, Luis; Ponce, Enrique
Direct current (DC) microgrids (MGs) are an emergent option to satisfy new demands for power quality and integration of renewable resources in electrical distribution systems. This work addresses the large-signal stability analysis of a DC-DC bidirectional converter (DBC) connected to a storage device in an islanding MG. This converter is responsible for controlling the balance of power (load demand and generation) under constant power loads (CPLs). In order to control the DC bus voltage through a DBC, we propose a robust sliding mode control (SMC) based on a washout filter. Dynamical systems techniques are exploited to assess the quality of this switching control strategy. In this sense, a bifurcation analysis is performed to study the nonlinear stability of a reduced model of this system. The appearance of different bifurcations when load parameters and control gains are changed is studied in detail. In the specific case of Teixeira Singularity (TS) bifurcation, some experimental results are provided, confirming the mathematical predictions. Both a deeper insight in the dynamic behavior of the controlled system and valuable design criteria are obtained.
The active learning hypothesis of the job-demand-control model: an experimental examination.
Häusser, Jan Alexander; Schulz-Hardt, Stefan; Mojzisch, Andreas
2014-01-01
The active learning hypothesis of the job-demand-control model [Karasek, R. A. 1979. "Job Demands, Job Decision Latitude, and Mental Strain: Implications for Job Redesign." Administration Science Quarterly 24: 285-307] proposes positive effects of high job demands and high job control on performance. We conducted a 2 (demands: high vs. low) × 2 (control: high vs. low) experimental office workplace simulation to examine this hypothesis. Since performance during a work simulation is confounded by the boundaries of the demands and control manipulations (e.g. time limits), we used a post-test, in which participants continued working at their task, but without any manipulation of demands and control. This post-test allowed for examining active learning (transfer) effects in an unconfounded fashion. Our results revealed that high demands had a positive effect on quantitative performance, without affecting task accuracy. In contrast, high control resulted in a speed-accuracy tradeoff, that is participants in the high control conditions worked slower but with greater accuracy than participants in the low control conditions.
Group size adjustment to ecological demand in a cooperative breeder.
Zöttl, Markus; Frommen, Joachim G; Taborsky, Michael
2013-04-07
Environmental factors can determine which group size will maximize the fitness of group members. This is particularly important in cooperative breeders, where group members often serve different purposes. Experimental studies are yet lacking to check whether ecologically mediated need for help will change the propensity of dominant group members to accept immigrants. Here, we manipulated the perceived risk of predation for dominant breeders of the cooperatively breeding cichlid fish Neolamprologus pulcher to test their response to unrelated and previously unknown immigrants. Potential immigrants were more readily accepted if groups were exposed to fish predators or egg predators than to herbivorous fish or control situations lacking predation risk. Our data are consistent with both risk dilution and helping effects. Egg predators were presented before spawning, which might suggest that the fish adjust acceptance rates also to a potential future threat. Dominant group members of N. pulcher apparently consider both present and future need of help based on ecological demand. This suggests that acceptance of immigrants and, more generally, tolerance of group members on demand could be a widespread response to ecological conditions in cooperatively breeding animals.
Energy manager design for microgrids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Firestone, Ryan; Marnay, Chris
2005-01-01
On-site energy production, known as distributed energy resources (DER), offers consumers many benefits, such as bill savings and predictability, improved system efficiency, improved reliability, control over power quality, and in many cases, greener electricity. Additionally, DER systems can benefit electric utilities by reducing congestion on the grid, reducing the need for new generation and transmission capacity, and offering ancillary services such as voltage support and emergency demand response. Local aggregations of distributed energy resources (DER) that may include active control of on-site end-use energy devices can be called microgrids. Microgrids require control to ensure safe operation and to make dispatchmore » decisions that achieve system objectives such as cost minimization, reliability, efficiency and emissions requirements, while abiding by system constraints and regulatory rules. This control is performed by an energy manager (EM). Preferably, an EM will achieve operation reasonably close to the attainable optimum, it will do this by means robust to deviations from expected conditions, and it will not itself incur insupportable capital or operation and maintenance costs. Also, microgrids can include supervision over end-uses, such as curtailing or rescheduling certain loads. By viewing a unified microgrid as a system of supply and demand, rather than simply a system of on-site generation devices, the benefits of integrated supply and demand control can be exploited, such as economic savings and improved system energy efficiency.« less
78 FR 21928 - Demand Response Coalition v. PJM Interconnection, L.L.C.; Notice of Complaint
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-12
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL13-57-000] Demand Response Coalition v. PJM Interconnection, L.L.C.; Notice of Complaint Take notice that on April 3, 2013, pursuant to... Demand Response Coalition \\1\\ (Complainant) filed a formal complaint against the PJM Interconnection, L.L...
Näswall, Katharina; Burt, Christopher D B; Pearce, Megan
2015-01-01
This study investigated the impact of workload demands on perceived job risk using the Job Demand-Control model as a research framework. The primary objective was to test the hypothesis that employee control over work scheduling and overtime would moderate the relationship between workload demands and perceived job risk. Ninety-six participants working in a variety of industries completed measures of workload demands, and of control over work scheduling and overtime, and a measure of perceived job risk. Workload demands predicted higher perceptions of job risk. However, the results also suggest that control over overtime moderated this relationship, where those with the combination of high workload demands and low control over overtime reported higher levels of perceived risk. The results indicate that the JDC model is applicable to safety research. The results suggest that employee control over workload demands is an important variable to consider in terms of managing workplace safety. The present study also points to important areas for future research to explore in order to further understand the connection between demands and safety.
ERIC Educational Resources Information Center
Kwok, Percy Lai Yin
2010-01-01
Based on some longitudinal studies of private tutoring in twelve cities, towns, municipalities and provinces of China, the paper endeavours to depict demand intensity, articulate market parameters and reflect on policy responses towards the demand-supply mechanism of the vast shadowy educational phenomena at primary and secondary levels. Such…
Integrated Platform for Automated Sustainable Demand Response in Smart Grids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zois, Vassilis; Frincu, Marc; Prasanna, Viktor K.
2014-10-08
Demand Response(DR) is a common practice used by utility providers to regulate energy demand. It is used at periods of high demand to minimize the peak to average consumption ratio. Several methods have been Demand Response(DR) is a common praon using information about the baseline consumption and the consumption during DR. Our goal is to provide a sustainable reduction to ensure the elimination of peaks in demand. The proposed system includes an adaptation mechanism for when the provided solution does not meet the DR requirements. We conducted a series of experiments using consumption data from a real life micro gridmore » to evaluate the efficiency as well as the robustness of our solution.« less
Schmitt, Antje; Den Hartog, Deanne N; Belschak, Frank D
2015-10-01
This study investigates the relationship between outcome responsibility and employees' well-being in terms of emotional exhaustion. Outcome responsibility is a job demand implying that employees' decisions at work have high material and/or nonmaterial consequences. Previous research indicates that outcome responsibility can have both positive and negative effects on employee well-being. Based on the person-job fit approach we hypothesize that whether or not outcome responsibility is positively or negatively related to emotional exhaustion depends on whether employees' behavioral style fits with this job demand. We investigate the role of proactive behavior as a personal resource that fits with high responsibility. We test our hypothesis in a multisource study among 138 employee-colleague dyads. Results of hierarchical moderated regression analysis reveal that peer-rated proactive behavior moderates the relationship between outcome responsibility and emotional exhaustion, such that the relationship is negative for employees showing high and nonsignificant for employees showing low proactivity. This finding holds also when controlling for trait positive and negative affect. The current study contributes to previous research on job design, proactivity, and occupational well-being and offers practical implications in terms of selection and training of employees for jobs high in outcome responsibility. (c) 2015 APA, all rights reserved).
Stimuli-responsive chitosan-based nanocarriers for cancer therapy
Fathi, Marziyeh; Sahandi Zangabad, Parham; Majidi, Sima; Barar, Jaleh; Erfan-Niya, Hamid
2017-01-01
Introduction: Stimuli-responsive nanocarriers offer unique advantages over the traditional drug delivery systems (DDSs) in terms of targeted drug delivery and on-demand release of cargo drug molecules. Of these, chitosan (CS)-based DDSs offer several advantages such as high compatibility with biological settings. Methods: In this study, we surveyed the literature in terms of the stimuli-responsive nanocarriers and discussed the most recent advancements in terms of CS-based nanosystems and their applications in cancer therapy and diagnosis. Results: These advanced DDSs are able to release the entrapped drugs in response to a specific endogenous stimulus (e.g., pH, glutathione concentration or certain enzymes) or exogenous stimulus (e.g., temperature, light, ultrasound, and magnetic field) at the desired time and target site. Dual-responsive nanocarriers by the combination of different stimuli have also been developed as efficient and improved DDSs. Among the stimuli-responsive nanocarriers, CS-based DDSs offer several advantages, including biocompatibility and biodegradability, antibacterial activity, ease of modification and functionalization, and non-immunogenicity. They are as one of the most ideal smart multifunction DDSs. Conclusion: The CS-based stimuli-responsive multifunctional nanosystems (NSs) offer unique potential for the targeted delivery of anticancer agents and provide great potential for on-demand and controlled-release of anticancer agents in response to diverse external/internal stimuli. PMID:29435435
Stimuli-responsive chitosan-based nanocarriers for cancer therapy.
Fathi, Marziyeh; Sahandi Zangabad, Parham; Majidi, Sima; Barar, Jaleh; Erfan-Niya, Hamid; Omidi, Yadollah
2017-01-01
Introduction: Stimuli-responsive nanocarriers offer unique advantages over the traditional drug delivery systems (DDSs) in terms of targeted drug delivery and on-demand release of cargo drug molecules. Of these, chitosan (CS)-based DDSs offer several advantages such as high compatibility with biological settings. Methods: In this study, we surveyed the literature in terms of the stimuli-responsive nanocarriers and discussed the most recent advancements in terms of CS-based nanosystems and their applications in cancer therapy and diagnosis. Results: These advanced DDSs are able to release the entrapped drugs in response to a specific endogenous stimulus (e.g., pH, glutathione concentration or certain enzymes) or exogenous stimulus (e.g., temperature, light, ultrasound, and magnetic field) at the desired time and target site. Dual-responsive nanocarriers by the combination of different stimuli have also been developed as efficient and improved DDSs. Among the stimuli-responsive nanocarriers, CS-based DDSs offer several advantages, including biocompatibility and biodegradability, antibacterial activity, ease of modification and functionalization, and non-immunogenicity. They are as one of the most ideal smart multifunction DDSs. Conclusion: The CS-based stimuli-responsive multifunctional nanosystems (NSs) offer unique potential for the targeted delivery of anticancer agents and provide great potential for on-demand and controlled-release of anticancer agents in response to diverse external/internal stimuli.
2015-05-07
Yerkes, R.M., and Dodson, J.D. (1908). The relation of strength of stimulus to rapidity of habit -formation. Journal of comparative neurology and psychology 18, 459-482. ...the amount of mental effort exerted (Kahneman, 1973; Beatty & Lucero-Wagoner, 2000; Andreassi, 2007). The vast majority of these studies , however...of this initial study , the authors were interested in investigating whether pupillometry data collected in a realistic UAV supervisory control
Parents and Adolescents Making Time Choices: "Choosing a Relationship"
ERIC Educational Resources Information Center
Ashbourne, Lynda M.; Daly, Kerry J.
2010-01-01
Drawing on 20 qualitative family interviews with mothers, fathers, and adolescents (aged 16 to 19 years), this study explores the time choices of parents and adolescents. Adolescents and their parents talk about having varying degrees of control over their time in response to external demands. They identify that they initiate time together and…
76 FR 67259 - Frequency Regulation Compensation in the Organized Wholesale Power Markets
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-31
... rapid action of turbine governor control to change a generator's output and of demand response resources... generators (e.g., water, steam and combustion turbines) that are specially equipped for this purpose... as adding a combustion turbine to the system for regulation purposes.'' \\54\\ \\53\\ Makarov, Y.V., Ma...
Dynamic alterations of hepatocellular function by on-demand elasticity and roughness modulation.
Uto, K; Aoyagi, T; DeForest, C A; Ebara, M
2018-05-01
Temperature-responsive cell culture substrates reported here can be dynamically programmed to induce bulk softening and surface roughness changes in the presence of living cells. Alterations in hepatocellular function following temporally controlled substrate softening depend on the extent of stiff mechanical priming prior to user-induced material transition.
The Use of Latex Gloves in the School Setting
ERIC Educational Resources Information Center
Purcell, Cathy Koeppen
2006-01-01
In 1987, when the U.S. Centers for Disease Control and Prevention recommended the use of universal precautions in response to the HIV/AIDS epidemic, the demand for medical gloves dramatically increased. Unfortunately, the manufacturing techniques for the most widely-used gloves--natural rubber latex--also changed, in order to expedite production.…
Oshio, Takashi; Tsutsumi, Akizumi; Inoue, Akiomi; Suzuki, Tomoko; Miyaki, Koichi
2017-11-25
Sickness presenteeism (SP) is postulated as workers' response to their general state of health; hence, SP is expected to affect workers' future health. In the present study, we examined the reciprocal relationship between SP and health in response to job stressors, with specific reference to psychological distress (PD) as workers' state of health. We conducted mediation analysis, using data from a three-wave cohort occupational survey conducted at 1-year intervals in Japan; it involved 1,853 employees (1,661 men and 192 women) of a manufacturing firm. We measured SP and PD, using the World Health Organization Health and Work Performance Questionnaire and Kessler 6 score, respectively. For job stressors, we considered job demands and control, effort and reward, and procedural and interactional justice. PD mediated 11.5%-36.2% of the impact of job control, reward, and procedural and interactional justice on SP, whereas SP mediated their impact on PD, albeit to a much lesser extent in the range of 3.4%-11.3%. Unlike in the cases of these job stressors related to job resources, neither SP nor PD mediated the impact of job demands or effort. Our results confirmed the reciprocal relationship between SP and PD in response to selected types of job stressors, emphasizing the need for more in-depth analysis of the dynamics of these associations.
Multivariate analysis of sludge disintegration by microwave-hydrogen peroxide pretreatment process.
Ya-Wei, Wang; Cheng-Min, Gui; Xiao-Tang, Ni; Mei-Xue, Chen; Yuan-Song, Wei
2015-01-01
Microwave irradiation (with H2O2) has been shown to offer considerable advantages owing to its flexible control, low overall cost, and resulting higher soluble chemical oxygen demand (SCOD); accordingly, the method has been proposed recently as a means of improving sludge disintegration. However, the key factor controlling this sludge pretreatment process, pH, has received insufficient attention to date. To address this, the response surface approach (central composite design) was applied to evaluate the effects of total suspended solids (TSS, 2-20 g/L), pH (4-10), and H2O2 dosage (0-2 w/w) and their interactions on 16 response variables (e.g., SCODreleased, pH, H2O2remaining). The results demonstrated that all three factors affect sludge disintegration significantly, and no pronounced interactions between response variables were observed during disintegration, except for three variables (TCOD, TSSremaining, and H2O2 remaining). Quadratic predictive models were constructed for all 16 response variables (R(2): 0.871-0.991). Taking soluble chemical oxygen demand (SCOD) as an example, the model and coefficients derived above were able to predict the performance of microwave pretreatment (enhanced by H2O2 and pH adjustment) from previously published studies. The predictive models developed were able to optimize the treatment process for multiple disintegration objectives. Copyright © 2014 Elsevier B.V. All rights reserved.
Hardware-in-the-Loop Co-simulation of Distribution Grid for Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rotger-Griful, Sergi; Chatzivasileiadis, Spyros; Jacobsen, Rune H.
2016-06-20
In modern power systems, co-simulation is proposed as an enabler for analyzing the interactions between disparate systems. This paper introduces the co-simulation platform Virtual Grid Integration Laboratory (VirGIL) including Hardware-in-the-Loop testing, and demonstrates its potential to assess demand response strategies. VirGIL is based on a modular architecture using the Functional Mock-up Interface industrial standard to integrate new simulators. VirGIL combines state-of-the-art simulators in power systems, communications, buildings, and control. In this work, VirGIL is extended with a Hardware-in-the-Loop component to control the ventilation system of a real 12-story building in Denmark. VirGIL capabilities are illustrated in three scenarios: load following,more » primary reserves and load following aggregation. Experimental results show that the system can track one minute changing signals and it can provide primary reserves for up-regulation. Furthermore, the potential of aggregating several ventilation systems is evaluated considering the impact at distribution grid level and the communications protocol effect.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin, Xin; Baker, Kyri A.; Christensen, Dane T.
This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility andmore » reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin, Xin; Baker, Kyri A; Isley, Steven C
This paper presents a user-preference-driven home energy management system (HEMS) for demand response (DR) with residential building loads and battery storage. The HEMS is based on a multi-objective model predictive control algorithm, where the objectives include energy cost, thermal comfort, and carbon emission. A multi-criterion decision making method originating from social science is used to quickly determine user preferences based on a brief survey and derive the weights of different objectives used in the optimization process. Besides the residential appliances used in the traditional DR programs, a home battery system is integrated into the HEMS to improve the flexibility andmore » reliability of the DR resources. Simulation studies have been performed on field data from a residential building stock data set. Appliance models and usage patterns were learned from the data to predict the DR resource availability. Results indicate the HEMS was able to provide a significant amount of load reduction with less than 20% prediction error in both heating and cooling cases.« less
Do job demands and job control affect problem-solving?
Bergman, Peter N; Ahlberg, Gunnel; Johansson, Gun; Stoetzer, Ulrich; Aborg, Carl; Hallsten, Lennart; Lundberg, Ingvar
2012-01-01
The Job Demand Control model presents combinations of working conditions that may facilitate learning, the active learning hypothesis, or have detrimental effects on health, the strain hypothesis. To test the active learning hypothesis, this study analysed the effects of job demands and job control on general problem-solving strategies. A population-based sample of 4,636 individuals (55% women, 45% men) with the same job characteristics measured at two times with a three year time lag was used. Main effects of demands, skill discretion, task authority and control, and the combined effects of demands and control were analysed in logistic regressions, on four outcomes representing general problem-solving strategies. Those reporting high on skill discretion, task authority and control, as well as those reporting high demand/high control and low demand/high control job characteristics were more likely to state using problem solving strategies. Results suggest that working conditions including high levels of control may affect how individuals cope with problems and that workplace characteristics may affect behaviour in the non-work domain.
Railing for safety: job demands, job control, and safety citizenship role definition.
Turner, Nick; Chmiel, Nik; Walls, Melanie
2005-10-01
This study investigated job demands and job control as predictors of safety citizenship role definition, that is, employees' role orientation toward improving workplace safety. Data from a survey of 334 trackside workers were framed in the context of R. A. Karasek's (1979) job demands-control model. High job demands were negatively related to safety citizenship role definition, whereas high job control was positively related to this construct. Safety citizenship role definition of employees with high job control was buffered from the influence of high job demands, unlike that of employees with low job control, for whom high job demands were related to lower levels of the construct. Employees facing both high job demands and low job control were less likely than other employees to view improving safety as part of their role orientation. Copyright (c) 2005 APA, all rights reserved.
Cui, Borui; Gao, Dian-ce; Xiao, Fu; ...
2016-12-23
This article provides a method in comprehensive evaluation of cost-saving potential of active cool thermal energy storage (CTES) integrated with HVAC system for demand management in non-residential building. The active storage is beneficial by shifting peak demand for peak load management (PLM) as well as providing longer duration and larger capacity of demand response (DR). In this research, a model-based optimal design method using genetic algorithm is developed to optimize the capacity of active CTES aiming for maximizing the life-cycle cost saving concerning capital cost associated with storage capacity as well as incentives from both fast DR and PLM. Inmore » the method, the active CTES operates under a fast DR control strategy during DR events while under the storage-priority operation mode to shift peak demand during normal days. The optimal storage capacities, maximum annual net cost saving and corresponding power reduction set-points during DR event are obtained by using the proposed optimal design method. Lastly, this research provides guidance in comprehensive evaluation of cost-saving potential of CTES integrated with HVAC system for building demand management including both fast DR and PLM.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cui, Borui; Gao, Dian-ce; Xiao, Fu
This article provides a method in comprehensive evaluation of cost-saving potential of active cool thermal energy storage (CTES) integrated with HVAC system for demand management in non-residential building. The active storage is beneficial by shifting peak demand for peak load management (PLM) as well as providing longer duration and larger capacity of demand response (DR). In this research, a model-based optimal design method using genetic algorithm is developed to optimize the capacity of active CTES aiming for maximizing the life-cycle cost saving concerning capital cost associated with storage capacity as well as incentives from both fast DR and PLM. Inmore » the method, the active CTES operates under a fast DR control strategy during DR events while under the storage-priority operation mode to shift peak demand during normal days. The optimal storage capacities, maximum annual net cost saving and corresponding power reduction set-points during DR event are obtained by using the proposed optimal design method. Lastly, this research provides guidance in comprehensive evaluation of cost-saving potential of CTES integrated with HVAC system for building demand management including both fast DR and PLM.« less
Auditory-Motor Processing of Speech Sounds
Möttönen, Riikka; Dutton, Rebekah; Watkins, Kate E.
2013-01-01
The motor regions that control movements of the articulators activate during listening to speech and contribute to performance in demanding speech recognition and discrimination tasks. Whether the articulatory motor cortex modulates auditory processing of speech sounds is unknown. Here, we aimed to determine whether the articulatory motor cortex affects the auditory mechanisms underlying discrimination of speech sounds in the absence of demanding speech tasks. Using electroencephalography, we recorded responses to changes in sound sequences, while participants watched a silent video. We also disrupted the lip or the hand representation in left motor cortex using transcranial magnetic stimulation. Disruption of the lip representation suppressed responses to changes in speech sounds, but not piano tones. In contrast, disruption of the hand representation had no effect on responses to changes in speech sounds. These findings show that disruptions within, but not outside, the articulatory motor cortex impair automatic auditory discrimination of speech sounds. The findings provide evidence for the importance of auditory-motor processes in efficient neural analysis of speech sounds. PMID:22581846
Light responsive hybrid nanofibres for on-demand therapeutic drug and cell delivery.
Li, Yan-Fang; Slemming-Adamsen, Peter; Wang, Jing; Song, Jie; Wang, Xueqin; Yu, Ying; Dong, Mingdong; Chen, Chunying; Besenbacher, Flemming; Chen, Menglin
2017-08-01
Smart materials for on-demand delivery of therapeutically active agents are challenging in pharmaceutical and biomaterials science. In the present study, we report hybrid nanofibres capable of being reversibly controlled to pulsatile deliver both therapeutic drugs and cells on-demand of near-infrared (NIR) light. The nanofibres, fabricated by co-electrospinning of poly (N-isopropylacrylamide), silica-coated gold nanorods and polyhedral oligomeric silsesquinoxanes have, for the first time, demonstrated rapid, reversible large-volume changes of 83% on-demand with NIR stimulation, with retained nanofibrous morphology. Combining with the extracellular matrix-mimicking fibrillary properties, the nanofibres achieved accelerated release of model drug or cells on demand with NIR triggering. The release of the model drug doxorubicin demonstrated normal anti-cancer efficacy by reducing the viability of human cervical cancer HeLa cells by 97% in 48 h. In parallel, the fibres allowed model cell NIH3T3 fibroblast entrapment, adhesion, proliferation, differentiation and, upon NIR irradiation, cell release with undisturbed cellular function. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
12 CFR 602.24 - Responses to demands served on non-FCA employees or entities.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Responses to demands served on non-FCA employees or entities. 602.24 Section 602.24 Banks and Banking FARM CREDIT ADMINISTRATION ADMINISTRATIVE... Not a Named Party § 602.24 Responses to demands served on non-FCA employees or entities. If you are...
Jagtap, Pranav; Diwadkar, Vaibhav A.
2016-01-01
Frontal-thalamic interactions are crucial for bottom-up gating and top-down control, yet have not been well studied from brain network perspectives. We applied network modeling of fMRI signals (Dynamic Causal Modeling; DCM) to investigate frontal-thalamic interactions during an attention task with parametrically varying levels of demand. fMRI was collected while subjects participated in a sustained continuous performance task with low and high attention demands. 162 competing model architectures were employed in DCM to evaluate hypotheses on bilateral frontal-thalamic connections and their modulation by attention demand, selected at a second level using Bayesian Model Selection. The model architecture evinced significant contextual modulation by attention of ascending (thalamus → dPFC) and descending (dPFC → thalamus) pathways. However, modulation of these pathways was asymmetric: While positive modulation of the ascending pathway was comparable across attention demand, modulation of the descending pathway was significantly greater when attention demands were increased. Increased modulation of the (dPFC → thalamus) pathway in response to increased attention demand constitutes novel evidence of attention-related gain in the connectivity of the descending attention pathway. By comparison demand-independent modulation of the ascending (thalamus → dPFC) pathway suggests unbiased thalamic inputs to the cortex in the context of the paradigm. PMID:27145923
Ethical and legal issues in the control of drug abuse and drug trafficking: the Nigerian case.
Obot, I S
1992-08-01
This paper presents a general review of drug law and policy in Nigeria beginning with the international attempts to control the traffic in liquor during the pre-colonial and colonial periods. The paper assesses the impact of penal policy on trafficking and use of illicit drugs at different stages in the transformation of Nigeria from a colonial outpost to an independent nation. One persistent feature of drug control mechanisms in Nigeria has been the emphasis on the reduction of supply with the imposition of harsh though inconsistent punishment including, at one time, the death penalty for trafficking. Consequently, initiatives aimed at demand reduction through education, treatment and rehabilitation have been neglected. One reason for this is that, to a great extent, drug control strategy in modern Nigeria has been a response to international demands; another is that they were formulated under military regimes with an overriding concern for law and order. Other features of the Nigerian drug problem are presented and the need for the reform of current laws is stressed. It is argued that an enduring solution lies in the implementation of a comprehensive but clearly defined policy aimed both at the control of supply and reduction of demand. While the state has the duty and the right to protect its citizens from drug-related harm, it is an ethical imperative to institute control measures which do no harm to the citizens they are meant to protect.
Essays on Mathematical Optimization for Residential Demand Response in the Energy Sector
NASA Astrophysics Data System (ADS)
Palaparambil Dinesh, Lakshmi
In the electric utility industry, it could be challenging to adjust supply to match demand due to large generator ramp up times, high generation costs and insufficient in-house generation capacity. Demand response (DR) is a technique for adjusting the demand for electric power instead of the supply. Direct Load Control (DLC) is one of the ways to implement DR. DLC program participants sign up for power interruption contracts and are given financial incentives for curtailing electricity usage during peak demand time periods. This dissertation studies a DLC program for residential air conditioners using mathematical optimization models. First, we develop a model that determines what contract parameters to use in designing contracts between the provider and residential customers, when to turn which power unit on or off and how much power to cut during peak demand hours. The model uses information on customer preferences for choice of contract parameters such as DLC financial incentives and energy usage curtailment. In numerical experiments, the proposed model leads to projected cost savings of the order of 20%, compared to a current benchmark model used in practice. We also quantify the impact of factors leading to cost savings and study characteristics of customers picked by different contracts. Second, we study a DLC program in a macro economic environment using a Computable General Equilibrium (CGE) model. A CGE model is used to study the impact of external factors such as policy and technology changes on different economic sectors. Here we differentiate customers based on their preference for DLC programs by using different values for price elasticity of demand for electricity commodity. Consequently, DLC program customers could substitute demand for electricity commodity with other commodities such as transportation sector. Price elasticity of demand is calculated using a novel methodology that incorporates customer preferences for DLC contracts from the first model. The calculation of elasticity based on our methodology is useful since the prices of commodities are not only determined by aggregate demand and supply but also by customers' relative preferences for commodities. In addition to this we quantify the indirect substitution and rebound effects on sectoral activity levels, incomes and prices based on customer differences, when DLC is implemented.
Static and Dynamic Measurements of Accommodation in Individuals with Down Syndrome
Manny, Ruth E.; Glasser, Adrian; Stuebing, Karla K.
2011-01-01
Purpose. To identify whether static and dynamic aspects of accommodation other than accuracy are deficient in individuals with Down syndrome (DS) and whether poor accommodation is related to sensory or motor pathway deficits. Methods. Static aspects of accommodation (maximum accommodative response and lag) were measured with an autorefractor for both proximal and minus lens demands. Dynamic aspects of accommodation (latency, peak velocity, microfluctuations) were recorded at 30 Hz with a custom-built photorefractor as subjects viewed a movie switching between 11 m and 50, 33, 25, or 20 cm. Thirty-six subjects with DS were recruited (age 3 to 39 years), and 24 (67%) had useable responses for at least one study measurement for comparison with 140 controls (3 to 40 years) from a previously published cohort. Results. DS subjects had lower maximum accommodative responses (mean = 2.52 ± 1.66 D) and higher lags (1.81 ± 1.30 D for 33 cm demand) than controls for both proximal and minus lens stimuli. DS subjects had greater microfluctuations (one-way ANCOVA, P < 0.001), and a small percentage of the total number of latency measurements (17% accommodative and 16% disaccommodative) were longer than controls. Peak velocities of accommodation and disaccommodation were not different between groups (one-way ANCOVA, P = 0.143). Conclusions. Peak velocities of accommodation and disaccommodation (primarily motor aspects) did not differ between controls and DS subjects; however, latencies (primarily sensory) and microfluctuations (combined motor and sensory) were poorer in DS subjects. These results suggest that poor accommodative accuracy in individuals with DS may be predominantly related to sensory deficits. PMID:20739471
[Investigation on job stress of pediatricians and nurses working in pediatric department].
Yao, San-qiao; Tian, Ling; Pang, Bao-dong; Bai, Yu-ping; Fan, Xue-yun; Shen, Fu-hai; Jin, Yu-lan
2008-09-01
To investigate the occupational stressors and modifiers of pediatricians and nurses in order to find the measurements for control of the job stress. 427 pediatricians and nurses working in five hospitals of a city served as subjects. Of them, the staff in section of pharmacy and toll offices in each hospital mentioned above served as control group. The General Job Stress Questionnaire was used to investigate the job stress by self-assessment. The scores of job demand, job risk, drug using, daily job stress, positive feelings, patient A behavior, physical environment and feeling balance in pediatricians and nurses were higher than those of control group, but the scores of job-person conflict, environmental control, technology utility, mental health, responsibility on things were lower than those of control group (P<0.05). The points of job future, job locus of control, self-esteem, job satisfaction, job load variance, depression in nurses were higher than those of pediatricians, and non-work activities, job risk and daily life stress were lower than those of doctors (P<0.05). The main affecting factors on job strain of pediatric staff included job monotony, higher job demand, more non-work job, lower job control, more job risk, job future ambiguous, poorer social support, lower job locus control and lower self-esteem. The stress degree of pediatric staff is higher than that of controls. The pediatricians have more job stress than that of nurses. The main stressors of pediatric staff are job monotony, higher job demand, more non-worker activity, lower job control, higher job risk and ambiguous job future. The main modifiers are good social support, external job locus of control and higher self-esteem.
Research on electricity market operation mechanism and its benefit of demand side participation
NASA Astrophysics Data System (ADS)
Han, Shuai; Yan, Xu; Qin, Li-juan; Lin, Xi-qiao; Zeng, Bo
2017-08-01
Demand response plays an important role in maintaining the economic stability of the system, and has the characteristics of high efficiency, low cost, fast response, good environmental benefits and so on. Demand side resource is an important part of electricity market. The research of demand side resources in our country is still in the initial stage, but the opening of the electricity sales side provides a broad prospect for the development of electricity market. This paper summarizes the main types of demand side resources in our country, analyzes the economic principle of demand response from the micro perspective, puts forward some suggestions on the operation mechanism of China’s demand side resources participating in the electricity market under the condition of electricity sales side opening, analyzes the current situation of pricing in the electricity wholesale market and sets up the pricing strategy of the centralized wholesale market with the demand side power supply participating in quotation, which makes the social and economic benefits reach the maximum.
NASA Technical Reports Server (NTRS)
Edwards, Tamsyn El; Martin, Lynne; Bienert, Nancy; Mercer, Joey
2017-01-01
In air traffic control, task demand and workload have important implications for the safety and efficiency of air traffic. Task demand is dynamic, however, research on demand transitions and associated controller perception and performance is limited. In addition, there is a comparatively restricted understanding of the influence of task demand transitions on workload and performance, in association with automation. This study used an air traffic control simulation to investigate the influence of task demand transitions and two conditions of varying automation, on workload and efficiency-related performance. Findings showed that a both the direction of the task demand variation, and the amount of automation, influenced the relationship between workload and performance. Further research is needed to enhance understanding of demand transition and workload history effects on operator experience and performance, in both air traffic control and other safety-critical domains.
Alejo, Teresa; Andreu, Vanesa; Mendoza, Gracia; Sebastian, Victor; Arruebo, Manuel
2018-08-01
Near-infrared (NIR) responsive nanoparticles are of great interest in the biomedical field as antennas for photothermal therapy and also as triggers for on-demand drug delivery. The present work reports the preparation of hollow gold nanoparticles (HGNPs) with plasmonic absorption in the NIR region covalently bound to a thermoresponsive polymeric shell that can be used as an on-demand drug delivery system for the release of analgesic drugs. The photothermal heating induced by the nanoparticles is able to produce the collapse of the polymeric shell thus generating the release of the local anesthetic bupivacaine in a spatiotemporally controlled way. Those HGNPs contain a 10 wt.% of polymer and present excellent reversible heating under NIR light excitation. Bupivacaine released at physiological temperature (37 °C) showed a pseudo-zero order release that could be spatiotemporally modified on-demand after applying several pulses of light/temperature above and below the lower critical solution temperature (LCST) of the polymeric shell. Furthermore, the nanomaterials obtained did not displayed detrimental effects on four mammalian cell lines at doses up to 0.2 mg/mL. From the results obtained it can be concluded than this type of hybrid thermoresponsive nanoparticle can be used as an externally activated on-demand drug delivery system. Copyright © 2018 Elsevier Inc. All rights reserved.
González Gómez, M P; Marín Arribas, S L; Vargas-Chacoff, L
2016-07-01
This study looks at how low infestation loads of adult Caligus rogercresseyi and other stressors affect the physiology of Salmo salar. Experimental fish groups were with (infested) or without (control) exposure to the parasite. The parasite cohort was followed for 78 days post-infestation (dpi), and only adult lice were observed. Additional stressors were applied at 60 and 75 dpi. The analysis included measurements of fish physiology and weight. Low-level infestations by adult C. rogercresseyi for more than 50 dpi induced moderate stress in S. salar as well as a high energy demand and increased small skin mucous cells. Threshold lice loads were identified, and above those loads, a high stress response was observed. Additional stressors altered fish physiology, inducing downregulation of the cortisol response after the first stressor and upregulation after the second stressor, but infested fish responded more strongly. Parasitism by C. rogercresseyi is energetically demanding, affecting the primary and secondary responses (e.g. cortisol and glucose levels), as well as the tertiary response (fish weight). © 2015 John Wiley & Sons Ltd.
Kane, Michael J; Core, Tammy J; Hunt, R Reed
2010-04-01
Psychological change is difficult to assess, in part because self-reported beliefs and attitudes may be biased or distorted. The present study probed belief change, in an educational context, by using the hindsight bias to counter another bias that generally plagues assessment of subjective change. Although research has indicated that skepticism courses reduce paranormal beliefs, those findings may reflect demand characteristics (biases toward desired, skeptical responses). Our hindsight-bias procedure circumvented demand by asking students, following semester-long skepticism (and control) courses, to recall their precourse levels of paranormal belief. People typically remember themselves as previously thinking, believing, and acting as they do now, so current skepticism should provoke false recollections of previous skepticism. Given true belief change, therefore, skepticism students should have remembered themselves as having been more skeptical than they were. They did, at least about paranormal topics that were covered most extensively in the course. Our findings thus show hindsight to be useful in evaluating cognitive change beyond demand characteristics.
Kuusio, Hannamaria; Heponiemi, Tarja; Sinervo, Timo; Elovainio, Marko
2010-06-01
To examine whether general practitioners (GP) working in primary health care have lower organizational commitment compared with physicians working in other health sectors. The authors also tested whether psychosocial factors (job demands, job control, and colleague consultation) explain these differences in commitment between GPs and other physicians. Cross-sectional postal questionnaire. Setting and participants. A postal questionnaire was sent to a random sample of physicians (n = 5000) drawn from the Finnish Association database in 2006. A total of 2841 physicians (response rate 57%) returned the questionnaire, of which 2657 (545 GPs and 2090 other physicians) fulfilled all the participant criteria. Organizational commitment was measured with two different indicators: intention to change jobs and low affective commitment. GPs were less committed to their organizations than other physicians. Work-related psychosocial factors (high job demands, low job control, and poor colleague consultation) were all significant risk factors for low organizational commitment. The evidence collected suggests that policies that reduce psychological demands, such as job demands and low control, may contribute to better organizational commitment and, thus, alleviate the shortages of physicians in primary care. Furthermore, giving GPs a stronger say in decisions concerning their work and providing them with more variety in work tasks may even improve the quality of primary care. The strategies for workplace development should focus on redesigning jobs and identifying GPs at higher risk, such as those with especially high job strain.
Field Testing of Telemetry for Demand Response Control of Small Loads
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lanzisera, Steven; Weber, Adam; Liao, Anna
The electricity system in California, from generation through loads, must be prepared for high renewable penetration and increased electrification of end uses while providing increased resilience and lower operating cost. California has an aggressive renewable portfolio standard that is complemented by world-leading greenhouse gas goals. The goal of this project was to evaluate methods of enabling fast demand response (DR) signaling to small loads for low-cost site enablement. We used OpenADR 2.0 to meet telemetry requirements for providing ancillary services, and we used a variety of low-cost devices coupled with open-source software to enable an end-to-end fast DR. The devices,more » architecture, implementation, and testing of the system is discussed in this report. We demonstrate that the emerging Internet of Things (IoT) and Smart Home movements provide an opportunity for diverse small loads to provide fast, low-cost demand response. We used Internet-connected lights, thermostats, load interruption devices, and water heaters to demonstrate an ecosystem of controllable devices. The system demonstrated is capable of providing fast load shed for between 20 dollars and $300 per kilowatt (kW) of available load. The wide range results from some loads may have very low cost but also very little shed capability (a 10 watt [W] LED light can only shed a maximum of 10 W) while some loads (e.g., water heaters or air conditioners) can shed several kilowatts but have a higher initial cost. These costs, however, compare well with other fast demand response costs, with typically are over $100/kilowatt of shed. We contend these loads are even more attractive than their price suggests because many of them will be installed for energy efficiency or non-energy benefits (e.g., improved lighting quality or controllability), and the ability to use them for fast DR is a secondary benefit. Therefore the cost of enabling them for DR may approach zero if a software-only solution can be deployed to enable fast DR after devices are installed for other reasons. We recommend that the DR research community continue to engage with the IoT community to encourage the use of documented and open development interfaces. A library of device drivers and machine-readable interface specifications would significantly reduce the burden on users or system integrators for deploying systems in large numbers of buildings in California.« less
Jahanshahi, Marjan
2013-01-01
Inhibition of inappropriate, habitual or prepotent responses is an essential component of executive control and a cornerstone of self-control. Via the hyperdirect pathway, the subthalamic nucleus (STN) receives inputs from frontal areas involved in inhibition and executive control. Evidence is reviewed from our own work and the literature suggesting that in Parkinson's disease (PD), deep brain stimulation (DBS) of the STN has an impact on executive control during attention-demanding tasks or in situations of conflict when habitual or prepotent responses have to be inhibited. These results support a role for the STN in an inter-related set of processes: switching from automatic to controlled processing, inhibitory and executive control, adjusting response thresholds and influencing speed-accuracy trade-offs. Such STN DBS-induced deficits in inhibitory and executive control may contribute to some of the psychiatric problems experienced by a proportion of operated cases after STN DBS surgery in PD. However, as no direct evidence for such a link is currently available, there is a need to provide direct evidence for such a link between STN DBS-induced deficits in inhibitory and executive control and post-surgical psychiatric complications experienced by operated patients. PMID:24399941
McVay, Jennifer C; Kane, Michael J
2009-01-01
On the basis of the executive-attention theory of working memory capacity (WMC; e.g., M. J. Kane, A. R. A. Conway, D. Z. Hambrick, & R. W. Engle, 2007), the authors tested the relations among WMC, mind wandering, and goal neglect in a sustained attention to response task (SART; a go/no-go task). In 3 SART versions, making conceptual versus perceptual processing demands, subjects periodically indicated their thought content when probed following rare no-go targets. SART processing demands did not affect mind-wandering rates, but mind-wandering rates varied with WMC and predicted goal-neglect errors in the task; furthermore, mind-wandering rates partially mediated the WMC-SART relation, indicating that WMC-related differences in goal neglect were due, in part, to variation in the control of conscious thought.
Optimal Control of Distributed Energy Resources using Model Predictive Control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mayhorn, Ebony T.; Kalsi, Karanjit; Elizondo, Marcelo A.
2012-07-22
In an isolated power system (rural microgrid), Distributed Energy Resources (DERs) such as renewable energy resources (wind, solar), energy storage and demand response can be used to complement fossil fueled generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation. The problem is formulated as a multi-objective optimization problem with the goals of minimizing fuel costs and changes in power output of diesel generators, minimizingmore » costs associated with low battery life of energy storage and maintaining system frequency at the nominal operating value. Two control modes are considered for controlling the energy storage to compensate either net load variability or wind variability. Model predictive control (MPC) is used to solve the aforementioned problem and the performance is compared to an open-loop look-ahead dispatch problem. Simulation studies using high and low wind profiles, as well as, different MPC prediction horizons demonstrate the efficacy of the closed-loop MPC in compensating for uncertainties in wind and demand.« less
Taris, Toon W; Feij, Jan A
2004-11-01
The present 3-wave longitudinal study was an examination of job-related learning and strain as a function of job demand and job control. The participants were 311 newcomers to their jobs. On the basis of R. A. Karasek and T. Theorell's (1990) demand-control model, the authors predicted that high demand and high job control would lead to high levels of learning; low demand and low job control should lead to low levels of learning; high demand and low job control should lead to high levels of strain; and low demand and high job control should lead to low levels of strain. The relation between strain and learning was also examined. The authors tested the hypotheses using ANCOVA and structural equation modeling. The results revealed that high levels of strain have an adverse effect on learning; the reverse effect was not confirmed. It appears that Karasek and Theorell's model is very relevant when examining work socialization processes.
Ensemble of Thermostatically Controlled Loads: Statistical Physics Approach.
Chertkov, Michael; Chernyak, Vladimir
2017-08-17
Thermostatically controlled loads, e.g., air conditioners and heaters, are by far the most widespread consumers of electricity. Normally the devices are calibrated to provide the so-called bang-bang control - changing from on to off, and vice versa, depending on temperature. We considered aggregation of a large group of similar devices into a statistical ensemble, where the devices operate following the same dynamics, subject to stochastic perturbations and randomized, Poisson on/off switching policy. Using theoretical and computational tools of statistical physics, we analyzed how the ensemble relaxes to a stationary distribution and established a relationship between the relaxation and the statistics of the probability flux associated with devices' cycling in the mixed (discrete, switch on/off, and continuous temperature) phase space. This allowed us to derive the spectrum of the non-equilibrium (detailed balance broken) statistical system and uncover how switching policy affects oscillatory trends and the speed of the relaxation. Relaxation of the ensemble is of practical interest because it describes how the ensemble recovers from significant perturbations, e.g., forced temporary switching off aimed at utilizing the flexibility of the ensemble to provide "demand response" services to change consumption temporarily to balance a larger power grid. We discuss how the statistical analysis can guide further development of the emerging demand response technology.
Ensemble of Thermostatically Controlled Loads: Statistical Physics Approach
Chertkov, Michael; Chernyak, Vladimir
2017-01-17
Thermostatically Controlled Loads (TCL), e.g. air-conditioners and heaters, are by far the most wide-spread consumers of electricity. Normally the devices are calibrated to provide the so-called bang-bang control of temperature - changing from on to off , and vice versa, depending on temperature. Aggregation of a large group of similar devices into a statistical ensemble is considered, where the devices operate following the same dynamics subject to stochastic perturbations and randomized, Poisson on/off switching policy. We analyze, using theoretical and computational tools of statistical physics, how the ensemble relaxes to a stationary distribution and establish relation between the re- laxationmore » and statistics of the probability flux, associated with devices' cycling in the mixed (discrete, switch on/off , and continuous, temperature) phase space. This allowed us to derive and analyze spec- trum of the non-equilibrium (detailed balance broken) statistical system. and uncover how switching policy affects oscillatory trend and speed of the relaxation. Relaxation of the ensemble is of a practical interest because it describes how the ensemble recovers from significant perturbations, e.g. forceful temporary switching o aimed at utilizing flexibility of the ensemble in providing "demand response" services relieving consumption temporarily to balance larger power grid. We discuss how the statistical analysis can guide further development of the emerging demand response technology.« less
Ensemble of Thermostatically Controlled Loads: Statistical Physics Approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chertkov, Michael; Chernyak, Vladimir
Thermostatically Controlled Loads (TCL), e.g. air-conditioners and heaters, are by far the most wide-spread consumers of electricity. Normally the devices are calibrated to provide the so-called bang-bang control of temperature - changing from on to off , and vice versa, depending on temperature. Aggregation of a large group of similar devices into a statistical ensemble is considered, where the devices operate following the same dynamics subject to stochastic perturbations and randomized, Poisson on/off switching policy. We analyze, using theoretical and computational tools of statistical physics, how the ensemble relaxes to a stationary distribution and establish relation between the re- laxationmore » and statistics of the probability flux, associated with devices' cycling in the mixed (discrete, switch on/off , and continuous, temperature) phase space. This allowed us to derive and analyze spec- trum of the non-equilibrium (detailed balance broken) statistical system. and uncover how switching policy affects oscillatory trend and speed of the relaxation. Relaxation of the ensemble is of a practical interest because it describes how the ensemble recovers from significant perturbations, e.g. forceful temporary switching o aimed at utilizing flexibility of the ensemble in providing "demand response" services relieving consumption temporarily to balance larger power grid. We discuss how the statistical analysis can guide further development of the emerging demand response technology.« less
Seismic Response Control Of Structures Using Semi-Active and Passive Variable Stiffness Devices
NASA Astrophysics Data System (ADS)
Salem, Mohamed M. A.
Controllable devices such as Magneto-Rheological Fluid Dampers, Electro-Rheological Dampers, and controllable friction devices have been studied extensively with limited implementation in real structures. Such devices have shown great potential in reducing seismic demands, either as smart base isolation systems, or as smart devices for multistory structures. Although variable stiffness devices can be used for seismic control of structures, the vast majority of research effort has been given to the control of damping. The primary focus of this dissertation is to evaluate the seismic control of structures using semi-active and passive variable stiffness characteristics. Smart base isolation systems employing variable stiffness devices have been studied, and two semi-active control strategies are proposed. The control algorithms were designed to reduce the superstructure and base accelerations of seismically isolated structures subject to near-fault and far-field ground motions. Computational simulations of the proposed control algorithms on the benchmark structure have shown that excessive base displacements associated with the near-fault ground motions may be better mitigated with the use of variable stiffness devices. However, the device properties must be controllable to produce a wide range of stiffness changes for an effective control of the base displacements. The potential of controllable stiffness devices in limiting the base displacement due to near-fault excitation without compromising the performance of conventionally isolated structures, is illustrated. The application of passive variable stiffness devices for seismic response mitigation of multistory structures is also investigated. A stiffening bracing system (SBS) is proposed to replace the conventional bracing systems of braced frames. An optimization process for the SBS parameters has been developed. The main objective of the design process is to maintain a uniform inter-story drift angle over the building's height, which in turn would evenly distribute the seismic demand over the building. This behavior is particularly essential so that any possible damage is not concentrated in a single story. Furthermore, the proposed design ensures that additional damping devices distributed over the building's height work efficiently with their maximum design capacity, leading to a cost efficient design. An integrated and comprehensive design procedure that can be readily adopted by the current seismic design codes is proposed. An equivalent lateral force distribution is developed that shows a good agreement with the response history analyses in terms of seismic performance and demand prediction. This lateral force pattern explicitly accounts for the higher mode effect, the dynamic characteristics of the structure, the supplemental damping, and the site specific seismic hazard. Therefore, the proposed design procedure is considered as a standalone method for the design of SBS equipped buildings.
Jiang, Jiefeng; Beck, Jeffrey; Heller, Katherine; Egner, Tobias
2015-01-01
The anterior cingulate and lateral prefrontal cortices have been implicated in implementing context-appropriate attentional control, but the learning mechanisms underlying our ability to flexibly adapt the control settings to changing environments remain poorly understood. Here we show that human adjustments to varying control demands are captured by a reinforcement learner with a flexible, volatility-driven learning rate. Using model-based functional magnetic resonance imaging, we demonstrate that volatility of control demand is estimated by the anterior insula, which in turn optimizes the prediction of forthcoming demand in the caudate nucleus. The caudate's prediction of control demand subsequently guides the implementation of proactive and reactive attentional control in dorsal anterior cingulate and dorsolateral prefrontal cortices. These data enhance our understanding of the neuro-computational mechanisms of adaptive behaviour by connecting the classic cingulate-prefrontal cognitive control network to a subcortical control-learning mechanism that infers future demands by flexibly integrating remote and recent past experiences. PMID:26391305
Gilbert-Ouimet, Mahée; Brisson, Chantal; Milot, Alain; Vézina, Michel
2017-06-01
Accumulating evidence shows that psychosocial work factors of the demand-control and effort-reward imbalance models may contribute to increase blood pressure (BP). Women are more likely to be exposed to these psychosocial factors than men. Moreover, women spend twice as much time per week performing family responsibilities than men. This study aimed to evaluate the longitudinal association of the double exposure to psychosocial work factors and high family responsibilities in women with BP for a 5-year follow-up. At baseline, the study sample was composed of 1215 working women. Psychosocial work factors were measured using validated scales. Family responsibilities were measured using items related to "the number of children and their age" and "housework and children care." Ambulatory BP measures were taken every 15 minutes during a working day. Associations between psychosocial measures and BP were examined using analyses of covariance. Women with a double exposure to effort-reward imbalance and high family responsibilities had significantly higher BP means than women not exposed to these factors at baseline (diastolic: +2.75 mm Hg), at 3-year follow-up (systolic: +2.22 mm Hg and diastolic: +2.55 mm Hg), and at 5-year follow-up (systolic: +2.94 mm Hg and diastolic: + 3.10 mm Hg). No adverse effect on BP was observed for the double exposure to the psychosocial work factors of the demand-control model and high family responsibilities. A double exposure to effort-reward imbalance at work and high family responsibilities might contribute to elevated ambulatory BP at work among women. BP elevations related to this double exposure may persist for several years.
Statistical Capability Study of a Helical Grinding Machine Producing Screw Rotors
NASA Astrophysics Data System (ADS)
Holmes, C. S.; Headley, M.; Hart, P. W.
2017-08-01
Screw compressors depend for their efficiency and reliability on the accuracy of the rotors, and therefore on the machinery used in their production. The machinery has evolved over more than half a century in response to customer demands for production accuracy, efficiency, and flexibility, and is now at a high level on all three criteria. Production equipment and processes must be capable of maintaining accuracy over a production run, and this must be assessed statistically under strictly controlled conditions. This paper gives numerical data from such a study of an innovative machine tool and shows that it is possible to meet the demanding statistical capability requirements.
Fournier, Lisa R; Herbert, Rhonda J; Farris, Carrie
2004-10-01
This study examined how response mapping of features within single- and multiple-feature targets affects decision-based processing and attentional capacity demands. Observers judged the presence or absence of 1 or 2 target features within an object either presented alone or with distractors. Judging the presence of 2 features relative to the less discriminable of these features alone was faster (conjunction benefits) when the task-relevant features differed in discriminability and were consistently mapped to responses. Conjunction benefits were attributed to asynchronous decision priming across attended, task-relevant dimensions. A failure to find conjunction benefits for disjunctive conjunctions was attributed to increased memory demands and variable feature-response mapping for 2- versus single-feature targets. Further, attentional demands were similar between single- and 2-feature targets when response mapping, memory demands, and discriminability of the task-relevant features were equated between targets. Implications of the findings for recent attention models are discussed. (c) 2004 APA, all rights reserved
Fallahi, Majid; Motamedzade, Majid; Heidarimoghadam, Rashid; Soltanian, Ali Reza; Miyake, Shinji
2016-01-01
Background: The present study aimed to evaluate the operators’ mental workload (MW) of cement, city traffic control and power plant control centers using subjective and objective measures during system vital parameters monitoring. Methods: This cross-sectional study was conducted from June 2014 to February 2015 at the cement, city traffic control and power plant control centers. Electrocardiography and electroencephalography data were recorded from forty males during performing their daily working in resting, low mental workload (LMW), high mental workload (HMW) and recovery conditions (each block 5 minutes). The NASA-Task Load Index (TLX) was used to evaluate the subjective workload of the operators. Results: The results showed that increasing MW had a significant effect on the operators subjective responses in two conditions ([1,53] = 216.303, P < 0.001, η2 = 0.803). Also,the Task-MW interaction effect on operators subjective responses was significant (F [3, 53] = 12.628,P < 0.001, η2 = 0.417). Analysis of repeated measures analysis of variance (ANOVA) indicated that increasing mental demands had a significant effect on heart rate, low frequency/high frequency ratio, theta and alpha band activity. Conclusion: The results suggested that when operators’ mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers. Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions. PMID:27386425
Fallahi, Majid; Motamedzade, Majid; Heidarimoghadam, Rashid; Soltanian, Ali Reza; Miyake, Shinji
2016-01-01
The present study aimed to evaluate the operators' mental workload (MW) of cement, city traffic control and power plant control centers using subjective and objective measures during system vital parameters monitoring. This cross-sectional study was conducted from June 2014 to February 2015 at the cement, city traffic control and power plant control centers. Electrocardiography and electroencephalography data were recorded from forty males during performing their daily working in resting, low mental workload (LMW), high mental workload (HMW) and recovery conditions (each block 5 minutes). The NASA-Task Load Index (TLX) was used to evaluate the subjective workload of the operators. The results showed that increasing MW had a significant effect on the operators subjective responses in two conditions ([1,53] = 216.303, P < 0.001, η2 = 0.803). Also,the Task-MW interaction effect on operators subjective responses was significant (F [3, 53] = 12.628,P < 0.001, η2 = 0.417). Analysis of repeated measures analysis of variance (ANOVA) indicated that increasing mental demands had a significant effect on heart rate, low frequency/high frequency ratio, theta and alpha band activity. The results suggested that when operators' mental demands especially in traffic control and power plant tasks increased, their mental fatigue and stress level increased and their mental health deteriorated. Therefore, it may be necessary to implement an ergonomic program or administrative control to manage mental probably health in these control centers. Furthermore, by evaluating MW, the control center director can organize the human resources for each MW condition to sustain the appropriate performance as well as improve system functions.
Modulation of habit formation by levodopa in Parkinson's disease.
Marzinzik, Frank; Wotka, Johann; Wahl, Michael; Krugel, Lea K; Kordsachia, Catarina; Klostermann, Fabian
2011-01-01
Dopamine promotes the execution of positively reinforced actions, but its role for the formation of behaviour when feedback is unavailable remains open. To study this issue, the performance of treated/untreated patients with Parkinson's disease and controls was analysed in an implicit learning task, hypothesising dopamine-dependent adherence to hidden task rules. Sixteen patients on/off levodopa and fourteen healthy subjects engaged in a Go/NoGo paradigm comprising four equiprobable stimuli. One of the stimuli was defined as target which was first consistently preceded by one of the three non-target stimuli (conditioning), whereas this coupling was dissolved thereafter (deconditioning). Two task versions were presented: in a 'Go version', only the target cue required the execution of a button press, whereas non-target stimuli were not instructive of a response; in a 'NoGo version', only the target cue demanded the inhibition of the button press which was demanded upon any non-target stimulus. Levodopa influenced in which task version errors grew from conditioning to deconditioning: in unmedicated patients just as controls errors only rose in the NoGo version with an increase of incorrect responses to target cues. Contrarily, in medicated patients errors went up only in the Go version with an increase of response omissions to target cues. The error increases during deconditioning can be understood as a perpetuation of reaction tendencies acquired during conditioning. The levodopa-mediated modulation of this carry-over effect suggests that dopamine supports habit conditioning under the task demand of response execution, but dampens it when inhibition is required. However, other than in reinforcement learning, supporting dopaminergic actions referred to the most frequent, i. e., non-target behaviour. Since this is passive whenever selective actions are executed against an inactive background, dopaminergic treatment could in according scenarios contribute to passive behaviour in patients with Parkinson's disease.
Rodriguez, Guadalupe; Trejo, Grisel; Schiemann, Elizabeth; Quandt, Sara A; Daniel, Stephanie S; Sandberg, Joanne C; Arcury, Thomas A
2016-06-01
This analysis describes the work organization and domestic work experienced by migrant Latinas, and explores the linkage between work and health. Twenty Latina workers in North Carolina with at least one child under age 12 completed in-depth interviews focused on their work organization, domestic responsibilities, work-family conflict, health, and family health. Using a systematic qualitative analysis, these women described a demanding work organization that is contingent and exploitative, with little control or support. They also described demanding domestic roles, with gendered and unequal division of household work. The resulting work-family conflict affects their mental and physical health, and has negative effects on the care and health of their families. The findings from this study highlight that work stressors from an unfavorable work organization create work-family conflict, and that work-family conflict in this population has a negative influence on workers' health and health behaviors.
A Generalized Formulation of Demand Response under Market Environments
NASA Astrophysics Data System (ADS)
Nguyen, Minh Y.; Nguyen, Duc M.
2015-06-01
This paper presents a generalized formulation of Demand Response (DR) under deregulated electricity markets. The problem is scheduling and controls the consumption of electrical loads according to the market price to minimize the energy cost over a day. Taking into account the modeling of customers' comfort (i.e., preference), the formulation can be applied to various types of loads including what was traditionally classified as critical loads (e.g., air conditioning, lights). The proposed DR scheme is based on Dynamic Programming (DP) framework and solved by DP backward algorithm in which the stochastic optimization is used to treat the uncertainty, if any occurred in the problem. The proposed formulation is examined with the DR problem of different loads, including Heat Ventilation and Air Conditioning (HVAC), Electric Vehicles (EVs) and a newly DR on the water supply systems of commercial buildings. The result of simulation shows significant saving can be achieved in comparison with their traditional (On/Off) scheme.
ERIC Educational Resources Information Center
Lee, Jayoung; Puig, Ana; Lee, Sang Min
2012-01-01
The purpose of this study was to examine the effects of the Demand Control Model (DCM) and the Effort Reward Imbalance Model (ERIM) on academic burnout for Korean students. Specifically, this study identified the effects of the predictor variables based on DCM and ERIM (i.e., demand, control, effort, reward, Demand Control Ratio, Effort Reward…
Influence of job demands and job control on work-life balance among Taiwanese nurses.
Ng, Lee-Peng; Chen, I-Chi; Ng, Hui-Fuang; Lin, Bo-Yen; Kuar, Lok-Sin
2017-09-01
This study investigated the extent to which the job demands and job control of nurses were related to their work-life balance. The inability to achieve work-life balance is one of the major reasons for the declining retention rate among nurses. Job demands and job control are two major work domain factors that can have a significant influence on the work-life balance of nurses. The study measured the job demands, job control and work-life balance of 2040 nurses in eight private hospitals in Taiwan in 2013. Job demands and job control significantly predicted all the dimensions of work-life balance. Job demands increased the level of work-life imbalance among nurses. While job control showed positive effects on work/personal life enhancement, it was found to increase both work interference with personal life and personal life interference with work. Reducing the level of job demands (particularly for psychological demands) between family and career development and maintaining a proper level of job control are essential to the work-life balance of nurses. Flexible work practices and team-based management could be considered by nursing management to lessen job demand pressure and to facilitate job engagement and participation among nurses, thus promoting a better balance between work and personal life. © 2017 John Wiley & Sons Ltd.
32 CFR 1805.4 - Procedure for production.
Code of Federal Regulations, 2010 CFR
2010-07-01
... responsibility for the information sought in the demand shall determine whether any information or materials may properly be produced in response to the demand, except that NACIC Counsel may assert any and all legal... demand for production is made upon an employee, the employee shall immediately notify NACIC Counsel, who...
Manipulating perceptual parameters in a continuous performance task.
Shalev, Nir; Humphreys, Glyn; Demeyere, Nele
2018-02-01
Sustained attention (SA) is among the most studied faculties of human cognition, and thought to be crucial for many aspects of behavior. Measuring SA often relies on performance on a continuous, low-demanding task. Such continuous performance tasks (CPTs) have many variations, and sustained attention is typically estimated based on variability in reaction times. While relying on reaction times may be useful in some cases, it can pose a challenge when working with clinical populations. To increase interpersonal variability in task parameters that do not rely on speed, researchers have increased demands for memory and response inhibition. These approaches, however, may be confounded when used to assess populations that suffer from multiple cognitive deficits. In the current study, we propose a new approach for increasing task variability by increasing the attentional demands. In order to do so, we created a new variation of a CPT - a masked version, where inattention is more likely to cause misidentifying a target. After establishing that masking indeed decreases target detection, we further investigated which task parameter may influence response biases. To do so, we contrasted two versions of the CPT with different target/distractor ratio. We then established how perceptual parameters can be controlled independently in a CPT. Following the experimental manipulations, we tested the MCCPT with aging controls and chronic stroke patients to assure the task can be used with target populations. The results confirm the MCCPT as a task providing high sensitivity without relying on reaction speed, and feasible for patients.
Distributed control system for demand response by servers
NASA Astrophysics Data System (ADS)
Hall, Joseph Edward
Within the broad topical designation of smart grid, research in demand response, or demand-side management, focuses on investigating possibilities for electrically powered devices to adapt their power consumption patterns to better match generation and more efficiently integrate intermittent renewable energy sources, especially wind. Devices such as battery chargers, heating and cooling systems, and computers can be controlled to change the time, duration, and magnitude of their power consumption while still meeting workload constraints such as deadlines and rate of throughput. This thesis presents a system by which a computer server, or multiple servers in a data center, can estimate the power imbalance on the electrical grid and use that information to dynamically change the power consumption as a service to the grid. Implementation on a testbed demonstrates the system with a hypothetical but realistic usage case scenario of an online video streaming service in which there are workloads with deadlines (high-priority) and workloads without deadlines (low-priority). The testbed is implemented with real servers, estimates the power imbalance from the grid frequency with real-time measurements of the live outlet, and uses a distributed, real-time algorithm to dynamically adjust the power consumption of the servers based on the frequency estimate and the throughput of video transcoder workloads. Analysis of the system explains and justifies multiple design choices, compares the significance of the system in relation to similar publications in the literature, and explores the potential impact of the system.
NASA Astrophysics Data System (ADS)
Jin, L.; Borgeson, S.; Fredman, D.; Hans, L.; Spurlock, A.; Todd, A.
2015-12-01
California's renewable portfolio standard (2012) requires the state to get 33% of its electricity from renewable sources by 2020. Increased share of variable renewable sources such as solar and wind in the California electricity system may require more grid flexibility to insure reliable power services. Such grid flexibility can be potentially provided by changes in end use electricity consumptions in response to grid conditions (demand-response). In the solar case, residential consumption in the late afternoon can be used as reserve capacity to balance the drop in solar generation. This study presents our initial attempt to identify, from a behavior perspective, residential demand response potentials in relation to solar ramp events using a data-driven approach. Based on hourly residential energy consumption data, we derive representative daily load shapes focusing on discretionary consumption with an innovative clustering analysis technique. We aggregate the representative load shapes into behavior groups in terms of the timing and rhythm of energy use in the context of solar ramp events. Households of different behavior groups that are active during hours with high solar ramp rates are identified for capturing demand response potential. Insights into the nature and predictability of response to demand-response programs are provided.
Jalili, Nima A; Jaiswal, Manish K; Peak, Charles W; Cross, Lauren M; Gaharwar, Akhilesh K
2017-10-19
"Smart" hydrogels are an emerging class of biomaterials that respond to external stimuli and have been investigated for a range of biomedical applications, including therapeutic delivery and regenerative engineering. Stimuli-responsive nanogels constructed of thermoresponsive polymers such as poly(N-isopropylacrylamide-co-acrylamide) (poly(NIPAM-co-AM)) and magnetic nanoparticles (MNPs) have been developed as "smart carriers" for on-demand delivery of therapeutic biomolecules via magneto-thermal activation. However, due to their small size and systemic introduction, these poly(NIPAM-co-AM)/MNP nanogels result in limited control over long-term, localized therapeutic delivery. Here, we developed an injectable nanoengineered hydrogel loaded with poly(NIPAM-co-AM)/MNPs for localized, on-demand delivery of therapeutics (doxorubicin (DOX)). We have engineered shear-thinning and self-recoverable hydrogels by modulating the crosslinking density of a gelatin methacrylate (GelMA) network. Poly(NIPAM-co-AM)/MNP nanogels loaded with DOX were entrapped within a GelMA pre-polymer solution prior to crosslinking. The temperature and magnetic field dependent release of loaded DOX was observed from the nanoengineered hydrogels (GelMA/(poly(NIPAM-co-AM)/MNPs)). Finally, the in vitro efficacy of DOX released from injectable nanoengineered hydrogels was investigated using preosteoblast and osteosarcoma cells. Overall, these results demonstrated that the injectable nanoengineered hydrogels could be used for on-demand and localized therapeutic delivery for biomedical applications.
Pragmatic hydraulic theory predicts stomatal responses to climatic water deficits.
Sperry, John S; Wang, Yujie; Wolfe, Brett T; Mackay, D Scott; Anderegg, William R L; McDowell, Nate G; Pockman, William T
2016-11-01
Ecosystem models have difficulty predicting plant drought responses, partially from uncertainty in the stomatal response to water deficits in soil and atmosphere. We evaluate a 'supply-demand' theory for water-limited stomatal behavior that avoids the typical scaffold of empirical response functions. The premise is that canopy water demand is regulated in proportion to threat to supply posed by xylem cavitation and soil drying. The theory was implemented in a trait-based soil-plant-atmosphere model. The model predicted canopy transpiration (E), canopy diffusive conductance (G), and canopy xylem pressure (P canopy ) from soil water potential (P soil ) and vapor pressure deficit (D). Modeled responses to D and P soil were consistent with empirical response functions, but controlling parameters were hydraulic traits rather than coefficients. Maximum hydraulic and diffusive conductances and vulnerability to loss in hydraulic conductance dictated stomatal sensitivity and hence the iso- to anisohydric spectrum of regulation. The model matched wide fluctuations in G and P canopy across nine data sets from seasonally dry tropical forest and piñon-juniper woodland with < 26% mean error. Promising initial performance suggests the theory could be useful in improving ecosystem models. Better understanding of the variation in hydraulic properties along the root-stem-leaf continuum will simplify parameterization. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.
Leitman, David I; Wolf, Daniel H; Loughead, James; Valdez, Jeffrey N; Kohler, Christian G; Brensinger, Colleen; Elliott, Mark A; Turetsky, Bruce I; Gur, Raquel E; Gur, Ruben C
2011-01-01
Schizophrenia patients display impaired performance and brain activity during facial affect recognition. These impairments may reflect stimulus-driven perceptual decrements and evaluative processing abnormalities. We differentiated these two processes by contrasting responses to identical stimuli presented under different contexts. Seventeen healthy controls and 16 schizophrenia patients performed an fMRI facial affect detection task. Subjects identified an affective target presented amongst foils of differing emotions. We hypothesized that targeting affiliative emotions (happiness, sadness) would create a task demand context distinct from that generated when targeting threat emotions (anger, fear). We compared affiliative foil stimuli within a congruent affiliative context with identical stimuli presented in an incongruent threat context. Threat foils were analysed in the same manner. Controls activated right orbitofrontal cortex (OFC)/ventrolateral prefrontal cortex (VLPFC) more to affiliative foils in threat contexts than to identical stimuli within affiliative contexts. Patients displayed reduced OFC/VLPFC activation to all foils, and no activation modulation by context. This lack of context modulation coincided with a 2-fold decrement in foil detection efficiency. Task demands produce contextual effects during facial affective processing in regions activated during affect evaluation. In schizophrenia, reduced modulation of OFC/VLPFC by context coupled with reduced behavioural efficiency suggests impaired ventral prefrontal control mechanisms that optimize affective appraisal.
On-Demand Targeting: Investigating Biology with Proximity-Directed Chemistry
2016-01-01
Proximity enhancement is a central chemical tenet underpinning an exciting suite of small-molecule toolsets that have allowed us to unravel many biological complexities. The leitmotif of this opus is “tethering”—a strategy in which a multifunctional small molecule serves as a template to bring proteins/biomolecules together. Scaffolding approaches have been powerfully applied to control diverse biological outcomes such as protein–protein association, protein stability, activity, and improve imaging capabilities. A new twist on this strategy has recently appeared, in which the small-molecule probe is engineered to unleash controlled amounts of reactive chemical signals within the microenvironment of a target protein. Modification of a specific target elicits a precisely timed and spatially controlled gain-of-function (or dominant loss-of-function) signaling response. Presented herein is a unique personal outlook conceptualizing the powerful proximity-enhanced chemical biology toolsets into two paradigms: “multifunctional scaffolding” versus “on-demand targeting”. By addressing the latest advances and challenges in the established yet constantly evolving multifunctional scaffolding strategies as well as in the emerging on-demand precision targeting (and related) systems, this Perspective is aimed at choosing when it is best to employ each of the two strategies, with an emphasis toward further promoting novel applications and discoveries stemming from these innovative chemical biology platforms. PMID:26907082
On-Demand Targeting: Investigating Biology with Proximity-Directed Chemistry.
Long, Marcus J C; Poganik, Jesse R; Aye, Yimon
2016-03-23
Proximity enhancement is a central chemical tenet underpinning an exciting suite of small-molecule toolsets that have allowed us to unravel many biological complexities. The leitmotif of this opus is "tethering"-a strategy in which a multifunctional small molecule serves as a template to bring proteins/biomolecules together. Scaffolding approaches have been powerfully applied to control diverse biological outcomes such as protein-protein association, protein stability, activity, and improve imaging capabilities. A new twist on this strategy has recently appeared, in which the small-molecule probe is engineered to unleash controlled amounts of reactive chemical signals within the microenvironment of a target protein. Modification of a specific target elicits a precisely timed and spatially controlled gain-of-function (or dominant loss-of-function) signaling response. Presented herein is a unique personal outlook conceptualizing the powerful proximity-enhanced chemical biology toolsets into two paradigms: "multifunctional scaffolding" versus "on-demand targeting". By addressing the latest advances and challenges in the established yet constantly evolving multifunctional scaffolding strategies as well as in the emerging on-demand precision targeting (and related) systems, this Perspective is aimed at choosing when it is best to employ each of the two strategies, with an emphasis toward further promoting novel applications and discoveries stemming from these innovative chemical biology platforms.
Kafle, Arjun; Garcia, Kevin; Wang, Xiurong; Pfeffer, Philip E; Strahan, Gary D; Bücking, Heike
2018-06-02
Legumes form tripartite interactions with arbuscular mycorrhizal (AM) fungi and rhizobia, and both root symbionts exchange nutrients against carbon from their host. The carbon costs of these interactions are substantial, but our current understanding of how the host controls its carbon allocation to individual root symbionts is limited. We examined nutrient uptake and carbon allocation in tripartite interactions of Medicago truncatula under different nutrient supply conditions, and when the fungal partner had access to nitrogen, and followed the gene expression of several plant transporters of the SUT and SWEET family. Tripartite interactions led to synergistic growth responses and stimulated the phosphate and nitrogen uptake of the plant. Plant nutrient demand but also fungal access to nutrients played an important role for the carbon transport to different root symbionts, and the plant allocated more carbon to rhizobia under nitrogen demand, but more carbon to the fungal partner when nitrogen was available. These changes in carbon allocation were consistent with changes in the SUT and SWEET expression. Our study provides important insights into how the host plant controls its carbon allocation under different nutrient supply conditions and changes its carbon allocation to different root symbionts to maximize its symbiotic benefits. This article is protected by copyright. All rights reserved.
Explaining worker strain and learning: how important are emotional job demands?
Taris, Toon W; Schreurs, Paul J G
2009-05-01
This study examined the added value of emotional job demands in explaining worker well-being, relative to the effects of task characteristics, such as quantitative job demands, job control, and coworker support. Emotional job demands were expected to account for an additional proportion of the variance in well-being. Cross-sectional data were obtained from 11,361 female Dutch home care employees. Hierarchical stepwise regression analysis demonstrated that low control, low support and high quantitative demands were generally associated with lower well-being (as measured in terms of emotional exhaustion, dedication, professional accomplishment and learning). Moreover, high emotional demands were in three out of four cases significantly associated with adverse well-being, in these cases accounting for an additional 1-6% of the variance in the outcome variables. In three out of eight cases the main effects of emotional demands on well-being were qualified by support and control, such that high control and high support either buffered the adverse effects of high emotional demands on well-being or increased the positive effects thereof. All in all, high emotional demands are as important a risk factor for worker well-being as well-established concepts like low job control and high quantitative job demands.
Cognitive task demands, self-control demands and the mental well-being of office workers.
Bridger, Robert S; Brasher, Kate
2011-09-01
The cognitive task demands of office workers and the self-control demands of their work roles were measured in a sample of 196 employees in two different office layouts using a self-report questionnaire, which was circulated electronically. Multiple linear regression analysis revealed that both factors were associated with mental well-being, but not with physical well-being, while controlling for exposure to psychosocial stressors. The interaction between cognitive task demands and self-control demands had the strongest association with mental well-being, suggesting that the deleterious effect of one was greater when the other was present. An exploratory analysis revealed that the association was stronger for employees working in a large open-plan office than for those working in smaller offices with more privacy. Frustration of work goals was the cognitive task demand having the strongest negative impact on mental well-being. Methodological limitations and scale psychometrics (particularly the use of the NASA Task Load Index) are discussed. STATEMENT OF RELEVANCE: Modern office work has high mental demands and low physical demands and there is a need to design offices to prevent adverse psychological reactions. It is shown that cognitive task demands interact with self-control demands to degrade mental well-being. The association was stronger in an open-plan office.
Treshow, M.
1959-02-10
A reactor system incorporating a reactor of the heterogeneous boiling water type is described. The reactor is comprised essentially of a core submerged adwater in the lower half of a pressure vessel and two distribution rings connected to a source of water are disposed within the pressure vessel above the reactor core, the lower distribution ring being submerged adjacent to the uppcr end of the reactor core and the other distribution ring being located adjacent to the top of the pressure vessel. A feed-water control valve, responsive to the steam demand of the load, is provided in the feedwater line to the distribution rings and regulates the amount of feed water flowing to each distribution ring, the proportion of water flowing to the submerged distribution ring being proportional to the steam demand of the load. This invention provides an automatic means exterior to the reactor to control the reactivity of the reactor over relatively long periods of time without relying upon movement of control rods or of other moving parts within the reactor structure.
Refrigerated Warehouse Demand Response Strategy Guide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scott, Doug; Castillo, Rafael; Larson, Kyle
This guide summarizes demand response measures that can be implemented in refrigerated warehouses. In an appendix, it also addresses related energy efficiency opportunities. Reducing overall grid demand during peak periods and energy consumption has benefits for facility operators, grid operators, utility companies, and society. State wide demand response potential for the refrigerated warehouse sector in California is estimated to be over 22.1 Megawatts. Two categories of demand response strategies are described in this guide: load shifting and load shedding. Load shifting can be accomplished via pre-cooling, capacity limiting, and battery charger load management. Load shedding can be achieved by lightingmore » reduction, demand defrost and defrost termination, infiltration reduction, and shutting down miscellaneous equipment. Estimation of the costs and benefits of demand response participation yields simple payback periods of 2-4 years. To improve demand response performance, it’s suggested to install air curtains and another form of infiltration barrier, such as a rollup door, for the passageways. Further modifications to increase efficiency of the refrigeration unit are also analyzed. A larger condenser can maintain the minimum saturated condensing temperature (SCT) for more hours of the day. Lowering the SCT reduces the compressor lift, which results in an overall increase in refrigeration system capacity and energy efficiency. Another way of saving energy in refrigerated warehouses is eliminating the use of under-floor resistance heaters. A more energy efficient alternative to resistance heaters is to utilize the heat that is being rejected from the condenser through a heat exchanger. These energy efficiency measures improve efficiency either by reducing the required electric energy input for the refrigeration system, by helping to curtail the refrigeration load on the system, or by reducing both the load and required energy input.« less
Northwest Open Automated Demand Response Technology Demonstration Project
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kiliccote, Sila; Piette, Mary Ann; Dudley, Junqiao
The Lawrence Berkeley National Laboratory (LBNL) Demand Response Research Center (DRRC) demonstrated and evaluated open automated demand response (OpenADR) communication infrastructure to reduce winter morning and summer afternoon peak electricity demand in commercial buildings the Seattle area. LBNL performed this demonstration for the Bonneville Power Administration (BPA) in the Seattle City Light (SCL) service territory at five sites: Seattle Municipal Tower, Seattle University, McKinstry, and two Target stores. This report describes the process and results of the demonstration. OpenADR is an information exchange model that uses a client-server architecture to automate demand-response (DR) programs. These field tests evaluated the feasibilitymore » of deploying fully automated DR during both winter and summer peak periods. DR savings were evaluated for several building systems and control strategies. This project studied DR during hot summer afternoons and cold winter mornings, both periods when electricity demand is typically high. This is the DRRC project team's first experience using automation for year-round DR resources and evaluating the flexibility of commercial buildings end-use loads to participate in DR in dual-peaking climates. The lessons learned contribute to understanding end-use loads that are suitable for dispatch at different times of the year. The project was funded by BPA and SCL. BPA is a U.S. Department of Energy agency headquartered in Portland, Oregon and serving the Pacific Northwest. BPA operates an electricity transmission system and markets wholesale electrical power at cost from federal dams, one non-federal nuclear plant, and other non-federal hydroelectric and wind energy generation facilities. Created by the citizens of Seattle in 1902, SCL is the second-largest municipal utility in America. SCL purchases approximately 40% of its electricity and the majority of its transmission from BPA through a preference contract. SCL also provides ancillary services within its own balancing authority. The relationship between BPA and SCL creates a unique opportunity to create DR programs that address both BPA's and SCL's markets simultaneously. Although simultaneously addressing both market could significantly increase the value of DR programs for BPA, SCL, and the end user, establishing program parameters that maximize this value is challenging because of complex contractual arrangements and the absence of a central Independent System Operator or Regional Transmission Organization in the northwest.« less
Granholm, Eric; Ruiz, Ivan; Gallegos-Rodriguez, Yuliana; Holden, Jason; Link, Peter C
2016-10-15
The hypothesis that defeatist performance attitudes are associated with decreased goal-directed task effort and negative symptoms in consumers with schizophrenia was investigated by using pupillary responses as a biomarker of task effort. Pupillary dilation during cognitive tasks provides a biomarker of effort devoted to the task, with greater dilation indicating greater effort. Defeatist attitudes were assessed in 149 consumers with schizophrenia or schizoaffective disorder and 50 healthy control subjects, and consumers were divided into three groups (tertile split) with respect to severity of defeatist attitudes. Pupillary dilation responses were recorded during a digit-span task with three-, six-, and nine-digit spans. Effort allocation (pupillary responses) to the task increased as the processing load increased from low (three-digit) to moderate (six-digit) demands in healthy control subjects and consumers with schizophrenia with mild and moderate severity of defeatist attitudes. In contrast, consumers with severe defeatist attitudes did not increase their effort when processing demands increased from low to moderate loads. These consumers showed significantly less effort in the six-digit condition relative to consumers with mild defeatist attitudes. Moreover, consumers with severe defeatist attitudes showed significantly greater severity of negative symptoms relative to consumers with mild defeatist attitudes and negative symptoms were significantly correlated with defeatist attitudes. These results suggest a relationship between defeatist performance attitudes, goal-directed task effort indexed by pupillary responses, and negative symptoms in schizophrenia. The findings have implications for using cognitive therapy to reduce defeatist attitudes that may contribute to diminished effort and negative symptoms in schizophrenia. Published by Elsevier Inc.
Selective alignment of brain responses by task demands during semantic processing.
Baggio, Giosuè
2012-04-01
The way the brain binds together words to form sentences may depend on whether and how the arising cognitive representation is to be used in behavior. The amplitude of the N400 effect in event-related brain potentials is inversely correlated with the degree of fit of a word's meaning into a semantic representation of the preceding discourse. This study reports a double dissociation in the latency characteristics of the N400 effect depending on task demands. When participants silently read words in a sentence context, without issuing a relevant overt response, greater temporal alignment over recording sites occurs for N400 onsets than peaks. If however a behavior is produced - here pressing a button in a binary probe selection task - exactly the opposite pattern is observed, with stronger alignment of N400 peaks than onsets. The peak amplitude of the N400 effect correlates best with the latency characteristic showing less temporal dispersion. These findings suggest that meaning construction in the brain is subtly affected by task demands, and that there is complex functional integration between semantic combinatorics and control systems handling behavioral goals. Copyright © 2012 Elsevier Ltd. All rights reserved.
Making big tobacco give in: you lose, they win.
Wander, Nathaniel; Malone, Ruth E
2006-11-01
To better understand how the tobacco industry responds to tobacco control activists, we explored Philip Morris's response to demands that consumers in developing countries be informed about smoking risks, and analyzed the implications of negotiating with a tobacco company. We reviewed internal tobacco industry documents and related materials, constructed a case history of how Philip Morris responded to a shareholder campaign to require health warnings on cigarettes sold worldwide, and analyzed interactions between (1) socially responsible investment activists, (2) Philip Morris management, (3) institutional investors, and (4) industry competitors. After resisting for 11 years, Philip Morris unilaterally reversed direction, and proposed its own labeling initiative. While activists celebrated, Philip Morris's president detailed privately how the company would yield little and benefit disproportionately. Activists portrayed the tobacco industry as preying on the poor and uneducated and used delegitimization to drive a wedge between the industry and its financial and political allies. When Philip Morris "gave in" to their demands, it exchanged negative publicity for positive public relations and political credibility. Tobacco companies can appear to accommodate public health demands while securing strategic advantages. Negotiating with the tobacco industry can enhance its legitimacy and facilitate its ability to market deadly cigarettes without corresponding benefits to public health.
Oshio, Takashi; Tsutsumi, Akizumi; Inoue, Akiomi; Suzuki, Tomoko; Miyaki, Koichi
2017-01-01
Objectives: Sickness presenteeism (SP) is postulated as workers' response to their general state of health; hence, SP is expected to affect workers' future health. In the present study, we examined the reciprocal relationship between SP and health in response to job stressors, with specific reference to psychological distress (PD) as workers' state of health. Methods: We conducted mediation analysis, using data from a three-wave cohort occupational survey conducted at 1-year intervals in Japan; it involved 1,853 employees (1,661 men and 192 women) of a manufacturing firm. We measured SP and PD, using the World Health Organization Health and Work Performance Questionnaire and Kessler 6 score, respectively. For job stressors, we considered job demands and control, effort and reward, and procedural and interactional justice. Results: PD mediated 11.5%-36.2% of the impact of job control, reward, and procedural and interactional justice on SP, whereas SP mediated their impact on PD, albeit to a much lesser extent in the range of 3.4%-11.3%. Unlike in the cases of these job stressors related to job resources, neither SP nor PD mediated the impact of job demands or effort. Conclusions: Our results confirmed the reciprocal relationship between SP and PD in response to selected types of job stressors, emphasizing the need for more in-depth analysis of the dynamics of these associations. PMID:28993575
NASA Astrophysics Data System (ADS)
Avci, Mesut
A practical cost and energy efficient model predictive control (MPC) strategy is proposed for HVAC load control under dynamic real-time electricity pricing. The MPC strategy is built based on a proposed model that jointly minimizes the total energy consumption and hence, cost of electricity for the user, and the deviation of the inside temperature from the consumer's preference. An algorithm that assigns temperature set-points (reference temperatures) to price ranges based on the consumer's discomfort tolerance index is developed. A practical parameter prediction model is also designed for mapping between the HVAC load and the inside temperature. The prediction model and the produced temperature set-points are integrated as inputs into the MPC controller, which is then used to generate signal actions for the AC unit. To investigate and demonstrate the effectiveness of the proposed approach, a simulation based experimental analysis is presented using real-life pricing data. An actual prototype for the proposed HVAC load control strategy is then built and a series of prototype experiments are conducted similar to the simulation studies. The experiments reveal that the MPC strategy can lead to significant reductions in overall energy consumption and cost savings for the consumer. Results suggest that by providing an efficient response strategy for the consumers, the proposed MPC strategy can enable the utility providers to adopt efficient demand management policies using real-time pricing. Finally, a cost-benefit analysis is performed to display the economic feasibility of implementing such a controller as part of a building energy management system, and the payback period is identified considering cost of prototype build and cost savings to help the adoption of this controller in the building HVAC control industry.
Analysis of a Dynamic Multi-Track Airway Concept for Air Traffic Management
NASA Technical Reports Server (NTRS)
Wing, David J.; Smith, Jeremy C.; Ballin, Mark G.
2008-01-01
The Dynamic Multi-track Airways (DMA) Concept for Air Traffic Management (ATM) proposes a network of high-altitude airways constructed of multiple, closely spaced, parallel tracks designed to increase en-route capacity in high-demand airspace corridors. Segregated from non-airway operations, these multi-track airways establish high-priority traffic flow corridors along optimal routes between major terminal areas throughout the National Airspace System (NAS). Air traffic controllers transition aircraft equipped for DMA operations to DMA entry points, the aircraft use autonomous control of airspeed to fly the continuous-airspace airway and achieve an economic benefit, and controllers then transition the aircraft from the DMA exit to the terminal area. Aircraft authority within the DMA includes responsibility for spacing and/or separation from other DMA aircraft. The DMA controller is responsible for coordinating the entry and exit of traffic to and from the DMA and for traffic flow management (TFM), including adjusting DMA routing on a daily basis to account for predicted weather and wind patterns and re-routing DMAs in real time to accommodate unpredicted weather changes. However, the DMA controller is not responsible for monitoring the DMA for traffic separation. This report defines the mature state concept, explores its feasibility and performance, and identifies potential benefits. The report also discusses (a) an analysis of a single DMA, which was modeled within the NAS to assess capacity and determine the impact of a single DMA on regional sector loads and conflict potential; (b) a demand analysis, which was conducted to determine likely city-pair candidates for a nationwide DMA network and to determine the expected demand fraction; (c) two track configurations, which were modeled and analyzed for their operational characteristic; (d) software-prototype airborne capabilities developed for DMA operations research; (e) a feasibility analysis of key attributes in the concept design; (f) a near-term, transitional application of the DMA concept as a proving ground for new airborne technologies; and (g) conclusions. The analysis indicates that the operational feasibility of a national DMA network faces significant challenges, especially for interactions between DMAs and between DMA and non-DMA traffic. Provided these issues are resolved, sectors near DMAs could experience significant local capacity benefits.
Mass casualty events: blood transfusion emergency preparedness across the continuum of care.
Doughty, Heidi; Glasgow, Simon; Kristoffersen, Einar
2016-04-01
Transfusion support is a key enabler to the response to mass casualty events (MCEs). Transfusion demand and capability planning should be an integrated part of the medical planning process for emergency system preparedness. Historical reviews have recently supported demand planning for MCEs and mass gatherings; however, computer modeling offers greater insights for resource management. The challenge remains balancing demand and supply especially the demand for universal components such as group O red blood cells. The current prehospital and hospital capability has benefited from investment in the management of massive hemorrhage. The management of massive hemorrhage should address both hemorrhage control and hemostatic support. Labile blood components cannot be stockpiled and a large surge in demand is a challenge for transfusion providers. The use of blood components may need to be triaged and demand managed. Two contrasting models of transfusion planning for MCEs are described. Both illustrate an integrated approach to preparedness where blood transfusion services work closely with health care providers and the donor community. Preparedness includes appropriate stock management and resupply from other centers. However, the introduction of alternative transfusion products, transfusion triage, and the greater use of an emergency donor panel to provide whole blood may permit greater resilience. © 2016 AABB.
Huang, Jidong; Gwarnicki, Cezary; Xu, Xin; Caraballo, Ralph S; Wada, Roy; Chaloupka, Frank J
2018-04-21
While much is known about the demand for cigarettes, research on the demand for non-cigarette tobacco products and the cross-price impacts among those products is limited. This study aims to comprehensively examine the own- and cross-price elasticities of demand for tobacco and nicotine replacement products (NRPs) in the U.S. We analyzed market-level quarterly data on sales and prices of 15 different types of tobacco products and NRPs from 2007 to 2014, compiled from retail store scanner data. Fixed effects models with controls were used to estimate their own-price elasticities and cross-price elasticities between cigarettes and the other 14 products. Our results show that, except for cigars, the demand for combustible tobacco products was generally elastic, with the estimated own-price elasticity >1 (10% increase in prices reduces sales by >10%). The own-price elasticities for smokeless tobacco products were smaller than those for combustible tobacco, although not always significant. The demand for electronic cigarettes and NRPs was found to be elastic. The cross-price elasticities with respect to cigarettes were positive for cigarillos, little cigars, loose tobacco, pipe tobacco, electronic cigarettes and NRPs, but only results for little cigars, loose tobacco, pipe tobacco, and dissolvable lozenges were consistently significant. Our findings suggest demand for tobacco products and NRPs was responsive to changes in their own prices. Substitutions or positive cross-price impacts between cigarettes and certain other products exist. It is important that tobacco control policies take into account both own- and cross-price impacts among tobacco products and NRTs. Copyright © 2018 Elsevier Inc. All rights reserved.
Michigan's Statewide Travel Demand Model
DOT National Transportation Integrated Search
1999-09-01
The Travel Demand and Intermodal Services Section of Michigan's Department of Transportation is responsible for the development, maintenance and application of the Statewide Travel Demand Model. Michigan's Statewide and Urban Travel Demand Models are...
Demand Response Compensation Methodologies: Case Studies for Mexico
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gagne, Douglas A; Settle, Donald E; Aznar, Alexandra Y
This report examines various compensation methodologies for demand response programs in Mexico. This report presents three case studies, including New England, California, and Hawaii. Demand response (DR) can refer to a variety of approaches to changing the amount and timing of customers' electricity use, allowing the electricity supplier to more easily balance electricity supply and demand. The level of compensation for a DR program will depend greatly upon both the regulatory context of the electricity supplier, as well as the economic circumstances of the DR providers. For a regulated utility, a proposed compensation level may need to pass regulatory approval.more » To determine the value of DR resources, a regulatory body typically seeks to determine the costs that the utility would avoid if demand-side resources 'produce' energy.« less
ROLE OF ESTROGEN RECEPTOR-α ON FOOD DEMAND ELASTICITY
Minervini, Vanessa; Rowland, Neil E.; Robertson, Kimberly L.; Foster, Thomas C.
2016-01-01
Estrogens have been shown to have an inhibitory effect on food intake under free-feeding conditions, yet the effects of estrogens on food-maintained operant responding have been studied to a much lesser extent and, thus, are not well understood. Therefore, the purpose of the present experiment was to use a behavioral economics paradigm to assess differences in demand elasticity between mice with knockout of the estrogen receptor subtype α, knockout of subtype β, and their wild type controls. The mice responded in a closed economy, and the price of food was increased by increasing the fixed-ratio response requirement every four sessions. Overall, we found that mice with the knockout of receptor subtype α had the most elastic demand functions. Therefore, under these conditions, estrogens increased food seeking via activation of the receptor subtype α. The results were inconsistent with those reported by previous studies that employed free-feeding conditions. PMID:25869426
The economics of tobacco use in Jordan.
Sweis, Nadia J; Chaloupka, Frank J
2014-01-01
We conducted an independent survey of tobacco use in Jordan following the methods and template of the Global Adult Tobacco Survey. Using data collected on cigarette use and cigarette prices, we estimated the price elasticity of cigarette demand in Jordan. We used a 2-part model of cigarette demand. In the first part, we estimate the impact of prices on the decision to smoke while controlling for individual demographic and environmental characteristics. Conditional on smoking, we then estimate the effect of price on the number of cigarettes smoked. The total price elasticity of cigarette demand in Jordan was estimated to be -0.6. Smoking among women was found to be relatively unresponsive to price (elasticity of -0.01), whereas smoking among men was much more responsive to price (elasticity of -0.81). The price elasticity estimates suggest that significant increases in tobacco taxes are likely to be effective in reducing smoking in Jordan, particularly smoking among men.
ERIC Educational Resources Information Center
Zhao, Yong; Zhang, Gaoming, Li, Ning
2006-01-01
For the past two decades, China's economy has grown rapidly, averaging an astonishing 9 percent every year. One result of this growth has been the demand for more and better educational opportunities at the postsecondary level. In response, the Chinese government, which holds a tight control over its highly centralized education system, introduced…
Using microgrids to enhance energy security and resilience
Lu, Xiaonan; Wang, Jianhui; Guo, Liping
2016-12-05
Although microgrids are now widely studied, challenges still exist. A reliable control architecture needs to be developed to coordinate different devices. Advanced forecasting and demand response management approaches should be implemented to cope with the intermittence of renewable generation. Furthermore, interconnection issues should be further studied to eliminate the influence of microgrid integration and achieve coordinated operation throughout the system.
Design and Cosimulation of Hierarchical Architecture for Demand Response Control and Coordination
Bhattarai, Bishnu P.; Levesque, Martin; Bak-Jensen, Birgitte; ...
2016-12-07
Demand response (DR) plays a key role for optimum asset utilization and to avoid or delay the need of new infrastructure investment. However, coordinated execution of multiple DRs is desired to maximize the DR benefits. In this paper, we propose a hierarchical DR architecture (HDRA) to control and coordinate the performance of various DR categories such that the operation of every DR category is backed-up by time delayed action of the others. A reliable, cost-effective communication infrastructure based on ZigBee, WiMAX, and fibers is designed to facilitate the HDRA execution. The performance of the proposed HDRA is demonstrated from themore » power system and communication perspectives in a cosimulation environment applied to a 0.4 kV/400 kVA real distribution network considering electric vehicles as a potential DR resource (DRR). The power simulation is performed employing a real time digital simulator whereas the communication simulation is performed using OMNeT++. Finally, the HDRA performance demonstrated the maximum utilization of available DR potential by facilitating simultaneous execution of multiple DRs and enabling participation of single DRR for multiple grid applications.« less
Nanocomposite thin films for triggerable drug delivery.
Vannozzi, Lorenzo; Iacovacci, Veronica; Menciassi, Arianna; Ricotti, Leonardo
2018-05-01
Traditional drug release systems normally rely on a passive delivery of therapeutic compounds, which can be partially programmed, prior to injection or implantation, through variations in the material composition. With this strategy, the drug release kinetics cannot be remotely modified and thus adapted to changing therapeutic needs. To overcome this issue, drug delivery systems able to respond to external stimuli are highly desirable, as they allow a high level of temporal and spatial control over drug release kinetics, in an operator-dependent fashion. Areas covered: On-demand drug delivery systems actually represent a frontier in this field and are attracting an increasing interest at both research and industrial level. Stimuli-responsive thin films, enabled by nanofillers, hold a tremendous potential in the field of triggerable drug delivery systems. The inclusion of responsive elements in homogeneous or heterogeneous thin film-shaped polymeric matrices strengthens and/or adds intriguing properties to conventional (bare) materials in film shape. Expert opinion: This Expert Opinion review aims to discuss the approaches currently pursued to achieve an effective on-demand drug delivery, through nanocomposite thin films. Different triggering mechanisms allowing a fine control on drug delivery are described, together with current challenges and possible future applications in therapy and surgery.
Design and Cosimulation of Hierarchical Architecture for Demand Response Control and Coordination
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhattarai, Bishnu P.; Levesque, Martin; Bak-Jensen, Birgitte
Demand response (DR) plays a key role for optimum asset utilization and to avoid or delay the need of new infrastructure investment. However, coordinated execution of multiple DRs is desired to maximize the DR benefits. In this paper, we propose a hierarchical DR architecture (HDRA) to control and coordinate the performance of various DR categories such that the operation of every DR category is backed-up by time delayed action of the others. A reliable, cost-effective communication infrastructure based on ZigBee, WiMAX, and fibers is designed to facilitate the HDRA execution. The performance of the proposed HDRA is demonstrated from themore » power system and communication perspectives in a cosimulation environment applied to a 0.4 kV/400 kVA real distribution network considering electric vehicles as a potential DR resource (DRR). The power simulation is performed employing a real time digital simulator whereas the communication simulation is performed using OMNeT++. Finally, the HDRA performance demonstrated the maximum utilization of available DR potential by facilitating simultaneous execution of multiple DRs and enabling participation of single DRR for multiple grid applications.« less
Impacts of demand response and renewable generation in electricity power market
NASA Astrophysics Data System (ADS)
Zhao, Zhechong
This thesis presents the objective of the research which is to analyze the impacts of uncertain wind power and demand response on power systems operation and power market clearing. First, in order to effectively utilize available wind generation, it is usually given the highest priority by assigning zero or negative energy bidding prices when clearing the day-ahead electric power market. However, when congestion occurs, negative wind bidding prices would aggravate locational marginal prices (LMPs) to be negative in certain locations. A load shifting model is explored to alleviate possible congestions and enhance the utilization of wind generation, by shifting proper amount of load from peak hours to off peaks. The problem is to determine proper amount of load to be shifted, for enhancing the utilization of wind generation, alleviating transmission congestions, and making LMPs to be non-negative values. The second piece of work considered the price-based demand response (DR) program which is a mechanism for electricity consumers to dynamically manage their energy consumption in response to time-varying electricity prices. It encourages consumers to reduce their energy consumption when electricity prices are high, and thereby reduce the peak electricity demand and alleviate the pressure to power systems. However, it brings additional dynamics and new challenges on the real-time supply and demand balance. Specifically, price-sensitive DR load levels are constantly changing in response to dynamic real-time electricity prices, which will impact the economic dispatch (ED) schedule and in turn affect electricity market clearing prices. This thesis adopts two methods for examining the impacts of different DR price elasticity characteristics on the stability performance: a closed-loop iterative simulation method and a non-iterative method based on the contraction mapping theorem. This thesis also analyzes the financial stability of DR load consumers, by incorporating explicit LMP formulations and consumer payment requirements into the network-constrained unit commitment (NCUC) problem. The proposed model determines the proper amount of DR loads to be shifted from peak hours to off-peaks under ISO's direct load control, for reducing the operation cost and ensuring that consumer payments of DR loads will not deteriorate significantly after load shifting. Both MINLP and MILP models are discussed, and improved formulation strategies are presented.
Li, Yuanyuan; Li, Fei; He, Ning; Guo, Lanting; Huang, Xiaoqi; Lui, Su; Gong, Qiyong
2014-08-04
Impaired working memory is thought to be a core feature of attention deficit hyperactivity disorder (ADHD). Previous imaging studies investigating working memory in ADHD have used tasks involving different cognitive resources and ignoring the categorical judgments about objects that are essential parts of performance in visual working memory tasks, thus complicating the interpretation of their findings. In the present study, we explored differential neural activation in children and adolescents with ADHD and in healthy controls using functional magnetic resonance imaging (fMRI) with the categorical n-back task (CN-BT), which maximized demands for executive reasoning while holding memory demands constant. A total of 33 drug-naive, right-handed male ADHD without comorbidity (mean age 9.9±2.4 years) and 27 right-handed, healthy male controls (mean age 10.9±2.7 years) were recruited in the present study. Event-related fMRI was used to study differences in brain activity during the CN-BT between the two groups. The two groups did not differ in their accuracy in the CN-BT, although the ADHD patients showed significantly shorter reaction times to correct responses than did the controls. During the CN-BT, both ADHD patients and controls showed significant positive and negative activations by the correct responses, mainly in the sensory-motor pathways and the striato-cerebellum circuit. Additionally, the ADHD patients showed significantly higher activation in the bilateral globus pallidus and the right hippocampus compared with the controls. There was also a positive correlation between hyperactivation of the left globus pallidus and the reaction time to correct responses in ADHD. In contrast to controls, ADHD patients showed neural hyperactivation in the striatum and mediotemporal areas during a working memory task involving categorization. Hyperfunction in these areas might be the pathophysiological foundation of ADHD, related to the deficits of working memory and the impulsive symptoms. Copyright © 2014 Elsevier Inc. All rights reserved.
2014-01-01
Background Robotic-assisted walking after stroke provides intensive task-oriented training. But, despite the growing diffusion of robotic devices little information is available about cardiorespiratory and metabolic responses during electromechanically-assisted repetitive walking exercise. Aim of the study was to determine whether use of an end-effector gait training (GT) machine with body weight support (BWS) would affect physiological responses and energy cost of walking (ECW) in subacute post-stroke hemiplegic patients. Methods Participants: six patients (patient group: PG) with hemiplegia due to stroke (age: 66 ± 15y; time since stroke: 8 ± 3 weeks; four men) and 6 healthy subjects as control group (CG: age, 76 ± 7y; six men). Interventions: overground walking test (OWT) and GT-assisted walking with 0%, 30% and 50% BWS (GT-BWS0%, 30% and 50%). Main Outcome Measures: heart rate (HR), pulmonary ventilation, oxygen consumption, respiratory exchange ratio (RER) and ECW. Results Intervention conditions significantly affected parameter values in steady state (HR: p = 0.005, V’E: p = 0.001, V'O2: p < 0.001) and the interaction condition per group affected ECW (p = 0.002). For PG, the most energy (V’O2 and ECW) demanding conditions were OWT and GT-BWS0%. On the contrary, for CG the least demanding condition was OWT. On the GT, increasing BWS produced a decrease in energy and cardiac demand in both groups. Conclusions In PG, GT-BWS walking resulted in less cardiometabolic demand than overground walking. This suggests that GT-BWS walking training might be safer than overground walking training in subacute stroke patients. PMID:24720844
Delussu, Anna Sofia; Morone, Giovanni; Iosa, Marco; Bragoni, Maura; Traballesi, Marco; Paolucci, Stefano
2014-04-10
Robotic-assisted walking after stroke provides intensive task-oriented training. But, despite the growing diffusion of robotic devices little information is available about cardiorespiratory and metabolic responses during electromechanically-assisted repetitive walking exercise. Aim of the study was to determine whether use of an end-effector gait training (GT) machine with body weight support (BWS) would affect physiological responses and energy cost of walking (ECW) in subacute post-stroke hemiplegic patients. six patients (patient group: PG) with hemiplegia due to stroke (age: 66 ± 15y; time since stroke: 8 ± 3 weeks; four men) and 6 healthy subjects as control group (CG: age, 76 ± 7y; six men). overground walking test (OWT) and GT-assisted walking with 0%, 30% and 50% BWS (GT-BWS0%, 30% and 50%). heart rate (HR), pulmonary ventilation, oxygen consumption, respiratory exchange ratio (RER) and ECW. Intervention conditions significantly affected parameter values in steady state (HR: p = 0.005, V'E: p = 0.001, V'O2: p < 0.001) and the interaction condition per group affected ECW (p = 0.002). For PG, the most energy (V'O2 and ECW) demanding conditions were OWT and GT-BWS0%. On the contrary, for CG the least demanding condition was OWT. On the GT, increasing BWS produced a decrease in energy and cardiac demand in both groups. In PG, GT-BWS walking resulted in less cardiometabolic demand than overground walking. This suggests that GT-BWS walking training might be safer than overground walking training in subacute stroke patients.
28 CFR 0.177a - Antitrust civil investigative demands.
Code of Federal Regulations, 2010 CFR
2010-07-01
... JUSTICE Assigning Responsibility Concerning Applications for Orders Compelling Testimony or Production of..., United States Code, to compel testimony in response to antitrust civil investigative demands for oral...
Friedman, Amy L.; Burgess, Ashley; Ramaseshan, Karthik; Easter, Phil; Khatib, Dalal; Chowdury, Asadur; Arnold, Paul D.; Hanna, Gregory L.; Rosenberg, David R.; Diwadkar, Vaibhav A.
2017-01-01
In an effort to elucidate differences in functioning brain networks between youth with obsessive-compulsive disorder and controls, we used fMRI signals to analyze brain network interactions of the dorsal anterior cingulate cortex (dACC) during visually coordinated motor responses. Subjects made a uni-manual response to briefly presented probes, at periodic (allowing participants to maintain a “motor set”) or random intervals (demanding reactive responses). Network interactions were assessed using psycho-physiological interaction (PPI), a basic model of functional connectivity evaluating modulatory effects of the dACC in the context of each task condition. Across conditions, OCD were characterized by hyper-modulation by the dACC, with loci alternatively observed as both condition-general and condition-specific. Thus, dynamically driven task demands during simple uni-manual motor control induce compensatory network interactions in cortical-thalamic regions in OCD. These findings support previous research in OCD showing compensatory network interactions during complex memory tasks, but establish that these network effects are observed during basic sensorimotor processing. Thus, these patterns of network dysfunction may in fact be independent of the complexity of tasks used to induce brain network activity. Hypothesis-driven approaches coupled with sophisticated network analyses are a highly valuable approach in using fMRI to uncover mechanisms in disorders like OCD. PMID:27992792
Tschentscher, Nadja; Mitchell, Daniel; Duncan, John
2017-05-03
Fluid intelligence has been associated with a distributed cognitive control or multiple-demand (MD) network, comprising regions of lateral frontal, insular, dorsomedial frontal, and parietal cortex. Human fluid intelligence is also intimately linked to task complexity, and the process of solving complex problems in a sequence of simpler, more focused parts. Here, a complex target detection task included multiple independent rules, applied one at a time in successive task epochs. Although only one rule was applied at a time, increasing task complexity (i.e., the number of rules) impaired performance in participants of lower fluid intelligence. Accompanying this loss of performance was reduced response to rule-critical events across the distributed MD network. The results link fluid intelligence and MD function to a process of attentional focus on the successive parts of complex behavior. SIGNIFICANCE STATEMENT Fluid intelligence is intimately linked to the ability to structure complex problems in a sequence of simpler, more focused parts. We examine the basis for this link in the functions of a distributed frontoparietal or multiple-demand (MD) network. With increased task complexity, participants of lower fluid intelligence showed reduced responses to task-critical events. Reduced responses in the MD system were accompanied by impaired behavioral performance. Low fluid intelligence is linked to poor foregrounding of task-critical information across a distributed MD system. Copyright © 2017 Tschentscher et al.
A Review of Player Monitoring Approaches in Basketball: Current Trends and Future Directions.
Fox, Jordan L; Scanlan, Aaron T; Stanton, Robert
2017-07-01
Fox, JL, Scanlan, AT, and Stanton, R. A review of player monitoring approaches in basketball: current trends and future directions. J Strength Cond Res 31(7): 2021-2029, 2017-Effective monitoring of players in team sports such as basketball requires an understanding of the external demands and internal responses, as they relate to training phases and competition. Monitoring of external demands and internal responses allows coaching staff to determine the dose-response associated with the imposed training load (TL), and subsequently, if players are adequately prepared for competition. This review discusses measures reported in the literature for monitoring the external demands and internal responses of basketball players during training and competition. The external demands of training and competition were primarily monitored using time-motion analysis, with limited use of microtechnology being reported. Internal responses during training were typically measured using hematological markers, heart rate, various TL models, and perceptual responses such as rating of perceived exertion (RPE). Heart rate was the most commonly reported indicator of internal responses during competition with limited reporting of hematological markers or RPE. These findings show a large discrepancy between the reporting of external and internal measures and training and competition demands. Microsensors, however, may be a practical and convenient method of player monitoring in basketball to overcome the limitations associated with current approaches while allowing for external demands and internal responses to be recorded simultaneously. The triaxial accelerometers of microsensors seem well suited for basketball and warrant validation to definitively determine their place in the monitoring of basketball players. Coaching staff should make use of this technology by tracking individual player responses across the annual plan and using real-time monitoring to minimize factors such as fatigue and injury risk.
Blasi, Giuseppe; Taurisano, Paolo; Papazacharias, Apostolos; Caforio, Grazia; Romano, Raffaella; Lobianco, Luciana; Fazio, Leonardo; Di Giorgio, Annabella; Latorre, Valeria; Sambataro, Fabio; Popolizio, Teresa; Nardini, Marcello; Mattay, Venkata S; Weinberger, Daniel R; Bertolino, Alessandro
2010-04-01
Previous studies have reported abnormal prefrontal and cingulate activity during attentional control processing in schizophrenia. However, it is not clear how variation in attentional control load modulates activity within these brain regions in this brain disorder. The aim of this study in schizophrenia is to investigate the impact of increasing levels of attentional control processing on prefrontal and cingulate activity. Blood oxygen level-dependent (BOLD) responses of 16 outpatients with schizophrenia were compared with those of 21 healthy subjects while performing a task eliciting increasing levels of attentional control during event-related functional magnetic resonance imaging at 3 T. Results showed reduced behavioral performance in patients at greater attentional control levels. Imaging data indicated greater prefrontal activity at intermediate attentional control levels in patients but greater prefrontal and cingulate responses at high attentional control demands in controls. The BOLD activity profile of these regions in controls increased linearly with increasing cognitive loads, whereas in patients, it was nonlinear. Correlation analysis consistently showed differential region and load-specific relationships between brain activity and behavior in the 2 groups. These results indicate that varying attentional control load is associated in schizophrenia with load- and region-specific modification of the relationship between behavior and brain activity, possibly suggesting earlier saturation of cognitive capacity.
Muntaner, C; Schoenbach, C
1994-01-01
The authors use confirmatory factor analysis to investigate the psychosocial dimensions of work environments relevant to health outcomes, in a representative sample of five U.S. metropolitan areas. Through an aggregated inference system, scales from Schwartz and associates' job scoring system and from the Dictionary of Occupational Titles (DOT) were employed to examine two alternative models: the demand-control model of Karasek and Theorell and Johnson's demand-control-support model. Confirmatory factor analysis was used to test the two models. The two multidimensional models yielded better fits than an unstructured model. After allowing for the measurement error variance due to the method of assessment (Schwartz and associates' system or DOT), both models yielded acceptable goodness-of-fit indices, but the fit of the demand-control-support model was significantly better. Overall these results indicate that the dimensions of Control (substantive complexity of work, skill discretion, decision authority), Demands (physical exertion, physical demands and hazards), and Social Support (coworker and supervisor social supports) provide an acceptable account of the psychosocial dimensions of work associated with health outcomes.
Patel, Anita; D'Alessandro, Maryann M; Ireland, Karen J; Burel, W Greg; Wencil, Elaine B; Rasmussen, Sonja A
Personal protective equipment (PPE) that protects healthcare workers from infection is a critical component of infection control strategies in healthcare settings. During a public health emergency response, protecting healthcare workers from infectious disease is essential, given that they provide clinical care to those who fall ill, have a high risk of exposure, and need to be assured of occupational safety. Like most goods in the United States, the PPE market supply is based on demand. The US PPE supply chain has minimal ability to rapidly surge production, resulting in challenges to meeting large unexpected increases in demand that might occur during a public health emergency. Additionally, a significant proportion of the supply chain is produced off-shore and might not be available to the US market during an emergency because of export restrictions or nationalization of manufacturing facilities. Efforts to increase supplies during previous public health emergencies have been challenging. During the 2009 H1N1 influenza pandemic and the 2014 Ebola virus epidemic, the commercial supply chain of pharmaceutical and healthcare products quickly became critical response components. This article reviews lessons learned from these responses from a PPE supply chain and systems perspective and examines ways to improve PPE readiness for future responses.
Bias Momentum Sizing for Hovering Dual-Spin Platforms
NASA Technical Reports Server (NTRS)
Lim, Kyong B.; Shin, Jong-Yeob; Moerder, Daniel D.
2006-01-01
An atmospheric flight vehicle in hover is typically controlled by varying its thrust vector. Achieving both levitation and attitude control with the propulsion system places considerable demands on it for agility and precision, particularly if the vehicle is statically unstable, or nearly so. These demands can be relaxed by introducing an appropriately sized angular momentum bias aligned with the vehicle's yaw axis, thus providing an additional margin of attitude stability about the roll and pitch axes. This paper describes a methodical approach for trading off angular momentum bias level needed with desired levels of vehicle response due to the design disturbance environment given a vehicle's physical parameters. It also describes several simplifications that provide a more physical and intuitive understanding of dual-spin dynamics for hovering atmospheric vehicles. This approach also mitigates the need for control torques and inadvertent actuator saturation difficulties in trying to stabilize a vehicle via control torques produced by unsteady aerodynamics, thrust vectoring, and unsteady throttling. Simulation results, based on a subscale laboratory test flying platform, demonstrate significant improvements in the attitude control robustness of the vehicle with respect to both wind disturbances and off-center of gravity payload changes during flight.
Predictors of new graduate nurses' workplace well-being: testing the job demands-resources model.
Spence Laschinger, Heather K; Grau, Ashley L; Finegan, Joan; Wilk, Piotr
2012-01-01
New graduate nurses currently experience a stressful transition into the workforce, resulting in high levels of burnout and job turnover in their first year of practice. This study tested a theoretical model of new graduate nurses' worklife derived from the job demands-resources model to better understand how job demands (workload and bullying), job resources (job control and supportive professional practice environments), and a personal resource (psychological capital) combine to influence new graduate experiences of burnout and work engagement and, ultimately, health and job outcomes. A descriptive correlational design was used to test the hypothesized model in a sample of newly graduated nurses (N = 420) working in acute care hospitals in Ontario, Canada. Data were collected from July to November 2009. Participants were mailed questionnaires to their home address using the Total Design Method to improve response rates. All variables were measured using standardized questionnaires, and structural equation modeling was used to test the model. The final model fit statistics partially supported the original hypothesized model. In the final model, job demands (workload and bullying) predicted burnout and, subsequently, poor mental health. Job resources (supportive practice environment and control) predicted work engagement and, subsequently, lower turnover intentions. Burnout also was a significant predictor of turnover intent (a crossover effect). Furthermore, personal resources (psychological capital) significantly influenced both burnout and work engagement. The model suggests that managerial strategies targeted at specific job demands and resources can create workplace environments that promote work engagement and prevent burnout to support the retention and well-being of the new graduate nurse population.
Chiew, Kimberly S.; Braver, Todd S.
2015-01-01
The dual mechanisms of control account suggests that cognitive control may be implemented through relatively proactive mechanisms in anticipation of stimulus onset, or through reactive mechanisms, triggered in response to changing stimulus demands. Reward incentives and task-informative cues (signaling the presence/absence of upcoming cognitive demand) have both been found to influence cognitive control in a proactive or preparatory fashion; yet, it is currently unclear whether and how such cue effects interact. We investigated this in two experiments using an adapted flanker paradigm, where task-informative and reward incentive cues were orthogonally manipulated on a trial-by-trial basis. In Experiment 1, results indicated that incentives not only speed RTs, but specifically reduce both interference and facilitation effects when combined with task-informative cues, suggesting enhanced proactive attentional control. Experiment 2 manipulated the timing of incentive cue information, demonstrating that such proactive control effects were only replicated with sufficient time to process the incentive cue (Early Incentive); when incentive signals were presented close to target onset (Late Incentive) the primary effect was a speed-accuracy tradeoff. Together, results suggest that advance cueing may trigger differing control strategies, and that these strategies may critically depend on both the timing – and the motivational incentive – to use such cues. PMID:26322689
Alderling, Magnus; Theorell, Töres; de la Torre, Bartolomé; Lundberg, Ingvar
2006-01-01
Background Previous studies of the relationship between job strain and blood or saliva cortisol levels have been small and based on selected occupational groups. Our aim was to examine the association between job strain and saliva cortisol levels in a population-based study in which a number of potential confounders could be adjusted for. Methods The material derives from a population-based study in Stockholm on mental health and its potential determinants. Two data collections were performed three years apart with more than 8500 subjects responding to a questionnaire in both waves. In this paper our analyses are based on 529 individuals who held a job, participated in both waves as well as in an interview linked to the second wave. They gave saliva samples at awakening, half an hour later, at lunchtime and before going to bed on a weekday in close connection with the interview. Job control and job demands were assessed from the questionnaire in the second wave. Mixed models were used to analyse the association between the demand control model and saliva cortisol. Results Women in low strain jobs (high control and low demands) had significantly lower cortisol levels half an hour after awakening than women in high strain (low control and high demands), active (high control and high demands) or passive jobs (low control and low demands). There were no significant differences between the groups during other parts of the day and furthermore there was no difference between the job strain, active and passive groups. For men, no differences were found between demand control groups. Conclusion This population-based study, on a relatively large sample, weakly support the hypothesis that the demand control model is associated with saliva cortisol concentrations. PMID:17129377
On the demand for prescription drugs: heterogeneity in price responses.
Skipper, Niels
2013-07-01
This paper estimates the price elasticity of demand for prescription drugs using an exogenous shift in consumer co-payment caused by a reform in the Danish subsidy scheme for the general public. Using purchasing records for the entire Danish population, I show that the average price response for the most commonly used drug yields demand elasticities in the range of -0.36 to -0.5. The reform is shown to affect women, the elderly, and immigrants the most. Furthermore, this paper shows significant heterogeneity in the price response over different types of antibiotics, suggesting that the price elasticity of demand varies considerably even across relatively similar drugs. Copyright © 2012 John Wiley & Sons, Ltd.
None
2017-12-09
Learn what it will take to create tomorrow's net-zero energy home as scientists reveal the secrets of cool roofs, smart windows, and computer-driven energy control systems. The net-zero energy home: Scientists are working to make tomorrow's homes more than just energy efficient -- they want them to be zero energy. Iain Walker, a scientist in the Lab's Energy Performance of Buildings Group, will discuss what it takes to develop net-zero energy houses that generate as much energy as they use through highly aggressive energy efficiency and on-site renewable energy generation. Talking back to the grid: Imagine programming your house to use less energy if the electricity grid is full or price are high. Mary Ann Piette, deputy director of Berkeley Lab's building technology department and director of the Lab's Demand Response Research Center, will discuss how new technologies are enabling buildings to listen to the grid and automatically change their thermostat settings or lighting loads, among other demands, in response to fluctuating electricity prices. The networked (and energy efficient) house: In the future, your home's lights, climate control devices, computers, windows, and appliances could be controlled via a sophisticated digital network. If it's plugged in, it'll be connected. Bruce Nordman, an energy scientist in Berkeley Lab's Energy End-Use Forecasting group, will discuss how he and other scientists are working to ensure these networks help homeowners save energy.
Zhao, Pengfei; Zheng, Mingbin; Luo, Zhenyu; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Zheng, Cuifang; Ma, Yifan; Cai, Lintao
2015-09-24
Smart nanoparticles (NPs) that respond to external and internal stimulations have been developing to achieve optimal drug release in tumour. However, applying these smart NPs to attain high antitumour performance is hampered by limited drug carriers and inefficient spatiotemporal control. Here we report a noninvasive NIR-driven, temperature-sensitive DI-TSL (DOX/ICG-loaded temperature sensitive liposomes) co-encapsulating doxorubicin (DOX) and indocyanine green (ICG). This theranostic system applies thermo-responsive lipid to controllably release drug, utilizes the fluorescence (FL) of DOX/ICG to real-time trace the distribution of NPs, and employs DOX/ICG to treat cancer by chemo/photothermal therapy. DI-TSL exhibits uniform size distribution, excellent FL/size stability, enhanced response to NIR-laser, and 3 times increased drug release through laser irradiation. After endocytosis by MCF-7 breast adenocarcinoma cells, DI-TSL in cellular endosomes can cause hyperthermia through laser irradiation, then endosomes are disrupted and DI-TSL 'opens' to release DOX simultaneously for increased cytotoxicity. Furthermore, DI-TSL shows laser-controlled release of DOX in tumour, enhanced ICG and DOX retention by 7 times and 4 times compared with free drugs. Thermo-sensitive DI-TSL manifests high efficiency to promote cell apoptosis, and completely eradicate tumour without side-effect. DI-TSL may provide a smart strategy to release drugs on demand for combinatorial cancer therapy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
Learn what it will take to create tomorrow's net-zero energy home as scientists reveal the secrets of cool roofs, smart windows, and computer-driven energy control systems. The net-zero energy home: Scientists are working to make tomorrow's homes more than just energy efficient -- they want them to be zero energy. Iain Walker, a scientist in the Lab's Energy Performance of Buildings Group, will discuss what it takes to develop net-zero energy houses that generate as much energy as they use through highly aggressive energy efficiency and on-site renewable energy generation. Talking back to the grid: Imagine programming your house tomore » use less energy if the electricity grid is full or price are high. Mary Ann Piette, deputy director of Berkeley Lab's building technology department and director of the Lab's Demand Response Research Center, will discuss how new technologies are enabling buildings to listen to the grid and automatically change their thermostat settings or lighting loads, among other demands, in response to fluctuating electricity prices. The networked (and energy efficient) house: In the future, your home's lights, climate control devices, computers, windows, and appliances could be controlled via a sophisticated digital network. If it's plugged in, it'll be connected. Bruce Nordman, an energy scientist in Berkeley Lab's Energy End-Use Forecasting group, will discuss how he and other scientists are working to ensure these networks help homeowners save energy.« less
NASA Astrophysics Data System (ADS)
Zhao, Pengfei; Zheng, Mingbin; Luo, Zhenyu; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Zheng, Cuifang; Ma, Yifan; Cai, Lintao
2015-09-01
Smart nanoparticles (NPs) that respond to external and internal stimulations have been developing to achieve optimal drug release in tumour. However, applying these smart NPs to attain high antitumour performance is hampered by limited drug carriers and inefficient spatiotemporal control. Here we report a noninvasive NIR-driven, temperature-sensitive DI-TSL (DOX/ICG-loaded temperature sensitive liposomes) co-encapsulating doxorubicin (DOX) and indocyanine green (ICG). This theranostic system applies thermo-responsive lipid to controllably release drug, utilizes the fluorescence (FL) of DOX/ICG to real-time trace the distribution of NPs, and employs DOX/ICG to treat cancer by chemo/photothermal therapy. DI-TSL exhibits uniform size distribution, excellent FL/size stability, enhanced response to NIR-laser, and 3 times increased drug release through laser irradiation. After endocytosis by MCF-7 breast adenocarcinoma cells, DI-TSL in cellular endosomes can cause hyperthermia through laser irradiation, then endosomes are disrupted and DI-TSL ‘opens’ to release DOX simultaneously for increased cytotoxicity. Furthermore, DI-TSL shows laser-controlled release of DOX in tumour, enhanced ICG and DOX retention by 7 times and 4 times compared with free drugs. Thermo-sensitive DI-TSL manifests high efficiency to promote cell apoptosis, and completely eradicate tumour without side-effect. DI-TSL may provide a smart strategy to release drugs on demand for combinatorial cancer therapy.
The development of inhibitory control in preschool children: effects of "executive skills" training.
Dowsett, S M; Livesey, D J
2000-03-01
As one of several processes involved in the executive functioning of the cognitive system, inhibitory control plays a significant role in determining how various mental processes work together in the successful performance of a task. Studies of response inhibition have shown that although 3-year-old children have the cognitive capacity to learn the rules required for response control, indicated by the correct verbal response, developmental constraints prevent them from withholding the correct response (Bell & Livesey, 1985; Livesey & Morgan, 1991). Some argue that these abulic dissociations are relative to children's ability to reflect on the rules required for response control (Zelazo, Reznick, & Pinon, 1995). The current study showed that repeated exposure to tasks facilitating the acquisition of increasingly complex rule structures could improve inhibitory control (as measured by a go/no-go discrimination learning task), even in children aged 3 years. These tasks included a variant of Diamond and Boyer's (1989) modified version of the Wisconsin Card Sort Task and a simplification of the change paradigm (Logan & Burkell, 1986). It is argued that experience with these tasks increased the acquisition of complex rules by placing demands on executive processes. This includes response control and other executive functions, such as representational flexibility, the ability to maintain information in working memory, the selective control of attention, and proficiency at error correction. The role of experiential variables in the development of inhibitory control is discussed in terms of the interaction between neural development and appropriate executive task experience in the early years. Copyright 2000 John Wiley & Sons, Inc.
Data-driven modeling, control and tools for cyber-physical energy systems
NASA Astrophysics Data System (ADS)
Behl, Madhur
Energy systems are experiencing a gradual but substantial change in moving away from being non-interactive and manually-controlled systems to utilizing tight integration of both cyber (computation, communications, and control) and physical representations guided by first principles based models, at all scales and levels. Furthermore, peak power reduction programs like demand response (DR) are becoming increasingly important as the volatility on the grid continues to increase due to regulation, integration of renewables and extreme weather conditions. In order to shield themselves from the risk of price volatility, end-user electricity consumers must monitor electricity prices and be flexible in the ways they choose to use electricity. This requires the use of control-oriented predictive models of an energy system's dynamics and energy consumption. Such models are needed for understanding and improving the overall energy efficiency and operating costs. However, learning dynamical models using grey/white box approaches is very cost and time prohibitive since it often requires significant financial investments in retrofitting the system with several sensors and hiring domain experts for building the model. We present the use of data-driven methods for making model capture easy and efficient for cyber-physical energy systems. We develop Model-IQ, a methodology for analysis of uncertainty propagation for building inverse modeling and controls. Given a grey-box model structure and real input data from a temporary set of sensors, Model-IQ evaluates the effect of the uncertainty propagation from sensor data to model accuracy and to closed-loop control performance. We also developed a statistical method to quantify the bias in the sensor measurement and to determine near optimal sensor placement and density for accurate data collection for model training and control. Using a real building test-bed, we show how performing an uncertainty analysis can reveal trends about inverse model accuracy and control performance, which can be used to make informed decisions about sensor requirements and data accuracy. We also present DR-Advisor, a data-driven demand response recommender system for the building's facilities manager which provides suitable control actions to meet the desired load curtailment while maintaining operations and maximizing the economic reward. We develop a model based control with regression trees algorithm (mbCRT), which allows us to perform closed-loop control for DR strategy synthesis for large commercial buildings. Our data-driven control synthesis algorithm outperforms rule-based demand response methods for a large DoE commercial reference building and leads to a significant amount of load curtailment (of 380kW) and over $45,000 in savings which is 37.9% of the summer energy bill for the building. The performance of DR-Advisor is also evaluated for 8 buildings on Penn's campus; where it achieves 92.8% to 98.9% prediction accuracy. We also compare DR-Advisor with other data driven methods and rank 2nd on ASHRAE's benchmarking data-set for energy prediction.
Summary of the effects of engine throttle response on airplane formation-flying qualities
NASA Technical Reports Server (NTRS)
Walsh, Kevin R.
1992-01-01
A flight evaluation as conducted to determine the effect of engine throttle response characteristics on precision formation-flying qualities. A variable electronic throttle control system was developed and flight-tested on a TF-104G airplane with a J79-11B engine at the NASA Dryden Flight Research Facility. Ten research flights were flown to evaluate the effects of throttle gain, time delay, and fuel control rate limiting on engine handling qualities during a demanding precision wing formation task. Handling quality effects of lag filters and lead compensation time delays were also evaluated. Data from pilot ratings and comments indicate that throttle control system time delays and rate limits cause significant degradations in handling qualities. Threshold values for satisfactory (level 1) and adequate (level 2) handling qualities of these key variables are presented.
Better service, greater efficiency : transit management for demand response systems
DOT National Transportation Integrated Search
1999-01-01
This brochure briefly describes different technologies which can enhance demand response transit systems. It covers automated scheduling and dispatching, mobile data terminals, electronic identification cards, automatic vehicle location, and geograph...
Murphy, James G; Yurasek, Ali M; Meshesha, Lidia Z; Dennhardt, Ashley A; MacKillop, James; Skidmore, Jessica R; Martens, Matthew P
2014-07-01
Behavioral economic demand curves measure alcohol consumption as a function of price and may capture clinically relevant individual differences in alcohol-reinforcing efficacy. This study used a novel, behavioral-economic, hypothetical demand-curve paradigm to examine the association between family history of alcohol misuse and individual differences in both alcohol demand and the relative sensitivity of alcohol demand to next-day responsibilities. Participants were 207 college students (47% male, 68.5% White, 27.4% African American, Mage = 19.5 years) who reported at least one heavy drinking episode (5/4 or more drinks on one occasion for a man/woman) in the past month and completed two versions of an alcohol purchase task (APT) that assessed hypothetical alcohol consumption across 17 drink prices. In one APT (standard), students imagined they had no next-day responsibilities, and in the other, they imagined having a 10:00 a.m. test the next day. A series of analyses of covariance indicated that participants with at least one biological parent or grandparent who had misused alcohol reported similar levels of alcohol demand on the standard APT but significantly less sensitivity to the next-day academic responsibility as measured by the percentage of reduction in demand intensity and breakpoint across the no-responsibility and next-day-test conditions. These findings provide initial evidence that APTs might clarify one potential mechanism of risk conferred by family history. Young adult heavy drinkers with a family history of problematic drinking may be less sensitive to next-day responsibilities that might modulate drinking in drinkers without a family history of alcohol problems.
The effect of trunk flexion on lower-limb kinetics of able-bodied gait.
Kluger, David; Major, Matthew J; Fatone, Stefania; Gard, Steven A
2014-02-01
Able-bodied individuals spontaneously adopt crouch gait when walking with induced anterior trunk flexion, but the effect of this adaptation on lower-limb kinetics is unknown. Sustained forward trunk displacement during walking can greatly alter body center-of-mass location and necessitate a motor control response to maintain upright balance. Understanding this response may provide insight into the biomechanical demands on the lower-limb joints of spinal pathology that alter trunk alignment (e.g., flatback). The purpose of this study was to determine the effect of sustained trunk flexion on lower-limb kinetics in able-bodied gait, facilitating understanding of the effects of spinal pathologies. Subjects walked with three postures: 0° (normal upright), 25±7°, and 50±7° trunk flexion. With increased trunk flexion, decreased peak ankle plantar flexor moments were observed with increased energy absorption during stance. Sustained knee flexion during mid- and terminal stance decreased knee flexor moments, but energy absorption/generation remained unchanged across postures. Increased trunk flexion placed significant demand on the hip extensors, thus increasing peak hip extensor moments and energy generation. The direct relationship between trunk flexion and energy absorption/generation at the ankle and hip, respectively, suggest increased muscular demand during gait. These findings on able-bodied subjects might shed light on muscular demands associated with individuals having pathology-induced positive sagittal spine balance. Copyright © 2013 Elsevier B.V. All rights reserved.
A Novel Method to Increase LinLog CMOS Sensors’ Performance in High Dynamic Range Scenarios
Martínez-Sánchez, Antonio; Fernández, Carlos; Navarro, Pedro J.; Iborra, Andrés
2011-01-01
Images from high dynamic range (HDR) scenes must be obtained with minimum loss of information. For this purpose it is necessary to take full advantage of the quantification levels provided by the CCD/CMOS image sensor. LinLog CMOS sensors satisfy the above demand by offering an adjustable response curve that combines linear and logarithmic responses. This paper presents a novel method to quickly adjust the parameters that control the response curve of a LinLog CMOS image sensor. We propose to use an Adaptive Proportional-Integral-Derivative controller to adjust the exposure time of the sensor, together with control algorithms based on the saturation level and the entropy of the images. With this method the sensor’s maximum dynamic range (120 dB) can be used to acquire good quality images from HDR scenes with fast, automatic adaptation to scene conditions. Adaptation to a new scene is rapid, with a sensor response adjustment of less than eight frames when working in real time video mode. At least 67% of the scene entropy can be retained with this method. PMID:22164083
A novel method to increase LinLog CMOS sensors' performance in high dynamic range scenarios.
Martínez-Sánchez, Antonio; Fernández, Carlos; Navarro, Pedro J; Iborra, Andrés
2011-01-01
Images from high dynamic range (HDR) scenes must be obtained with minimum loss of information. For this purpose it is necessary to take full advantage of the quantification levels provided by the CCD/CMOS image sensor. LinLog CMOS sensors satisfy the above demand by offering an adjustable response curve that combines linear and logarithmic responses. This paper presents a novel method to quickly adjust the parameters that control the response curve of a LinLog CMOS image sensor. We propose to use an Adaptive Proportional-Integral-Derivative controller to adjust the exposure time of the sensor, together with control algorithms based on the saturation level and the entropy of the images. With this method the sensor's maximum dynamic range (120 dB) can be used to acquire good quality images from HDR scenes with fast, automatic adaptation to scene conditions. Adaptation to a new scene is rapid, with a sensor response adjustment of less than eight frames when working in real time video mode. At least 67% of the scene entropy can be retained with this method.
Mayer, Jutta S.; Park, Sohee
2014-01-01
Working memory (WM) impairment is a core feature of schizophrenia, but the contributions of different WM components are not yet specified. Here, we investigated the potential role of inefficient encoding in reduced WM performance in patients with schizophrenia (PSZ). Twenty-eight PSZ, 16 patients with bipolar disorder (PBP), 16 unaffected and unmedicated relatives of PSZ (REL), and 29 demographically matched healthy controls (HC) performed a spatial delayed response task with either low or high WM demands. The demands on attentional selection were also manipulated by presenting distractor stimuli during encoding in some of the trials. After each trial, participants rated their level of response confidence. This allowed us to analyze different types of WM responses. WM was severely impaired in PSZ compared to HC; this reduction was mainly due to an increase in the amount of false memory responses (incorrect responses that were given with high confidence) rather than an increase in the amount of incorrect and not-confident responses. Although PBP showed WM impairments, they did not have increased false memory errors. In contrast, reduced WM in REL was also accompanied by an increase in false memory errors. The presentation of distractors led to a decline in WM performance, which was comparable across groups indicating that attentional selection was intact in PSZ. These findings suggest that inefficient WM encoding is responsible for impaired WM in schizophrenia and point to differential mechanisms underlying WM impairments in PSZ and PBP. PMID:22708888
Pupil measures of alertness and mental load
NASA Technical Reports Server (NTRS)
Backs, Richard W.; Walrath, Larry C.
1988-01-01
A study of eight adults given active and passive search tasks showed that evoked pupillary response was sensitive to information processing demands. In particular, large pupillary diameter was observed in the active search condition where subjects were actively processing information relevant to task performance, as opposed to the passive search (control) condition where subjects passively viewed the displays. However, subjects may have simply been more aroused in the active search task. Of greater importance was that larger pupillary diameter, corresponding to longer search time, was observed for noncoded than for color-coded displays in active search. In the control condition, pupil diameter was larger with the color displays. The data indicate potential usefulness of pupillary responses in evaluating the information processing requirements of visual displays.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sparn, Bethany F; Ruth, Mark F; Krishnamurthy, Dheepak
Many have proposed that responsive load provided by distributed energy resources (DERs) and demand response (DR) are an option to provide flexibility to the grid and especially to distribution feeders. However, because responsive load involves a complex interplay between tariffs and DER and DR technologies, it is challenging to test and evaluate options without negatively impacting customers. This paper describes a hardware-in-the-loop (HIL) simulation system that has been developed to reduce the cost of evaluating the impact of advanced controllers (e.g., model predictive controllers) and technologies (e.g., responsive appliances). The HIL simulation system combines large-scale software simulation with a smallmore » set of representative building equipment hardware. It is used to perform HIL simulation of a distribution feeder and the loads on it under various tariff structures. In the reported HIL simulation, loads include many simulated air conditioners and one physical air conditioner. Independent model predictive controllers manage operations of all air conditioners under a time-of-use tariff. Results from this HIL simulation and a discussion of future development work of the system are presented.« less
JCQ scale reliability and responsiveness to changes in manufacturing process.
d'Errico, Angelo; Punnett, Laura; Gold, Judith E; Gore, Rebecca
2008-02-01
The job content questionnaire (JCQ) was administered to automobile manufacturing workers in two interviews, 5 years apart. Between the two interviews, the company introduced substantial changes in production technology in some production areas. The aims were: (1) to describe the impact of these changes on self-reported psychosocial exposures, and (2) to examine test-retest reliability of the JCQ scales, taking into account changes in job assignment and, for a subset of workers, physical ergonomic exposures as assessed through field observations. The study population included 790 subjects at the first and 519 at the second interview, of whom 387 were present in both. Differences in demand and control scores between interviews were analyzed by Wilcoxon matched-pairs signed-rank test. Test-retest reliability of these scales was evaluated by the intraclass correlation coefficient (ICC) and the Spearman's rho coefficient. The introduction of more automated technology produced an overall increase in job control but did not decrease psychological demand. The reliability of the control scale was low overall but increased to an acceptable level among workers who had not changed job. The demand scale had high reliability only among workers whose physical ergonomic exposures were similar on both survey occasions. These results show that 5-year test-retest reliability of self-reported psychosocial exposures is adequate among workers whose job assignment and ergonomic exposures have remained stable over time.
Kawada, Tomoyuki; Otsuka, Toshiaki
2011-01-01
Subjects with higher occupational position are speculated to have higher ability to handle with stress, and they were less affected by job stress. This study focused on the relationship between job satisfaction and three sub-scales of a brief job stress questionnaire (BJSQ) related to workload. This self-administered questionnaire was distributed to 371 employees of a company, and all the workers sent back their responses. Among the 57 items graded on a 4-point Likert-type scale to measure job stressors, psycho-physical complaints, and support for workers, the authors studied the influence of quantitative and qualitative job overload (six items), job control (three items), and support port (six items). The job satisfaction score estimated on a 4-point Likert-type scale was also used in relation to job stress determined using a 15-item scale from the BJSQ based on demand-control-support model. Occupational positions were classified into directors, managers, and general workers, and the content of job was classified into clerical workers, skilled technicians, and unskilled manual workers. All the scales on job stress presented acceptable alpha coefficients reflecting high internal consistency (job demand: 0.855, job control: 0.644, and support: 0.878, respectively). Principal axis factor analysis was conducted, and three factors were extracted; support, job demand and job control. There was a significant difference in the mean score among four groups divided by the job satisfaction level as evaluated by Dunnett's multiple comparison, and members who were dissatisfied with their job showed a high job demand, limited job control, and poor support. The mean score of support for managers were significantly higher (lower support) than that for general workers. The logistic regression analysis revealed that job control and support contributed significantly to job satisfaction. In addition, unskilled manual workers showed significantly higher job dissatisfaction compared with clerical workers. Worsening of job satisfaction was related to poor job control and lack of support. Strategies to alleviate job stress are therefore urgently needed.
Jagtap, Pranav; Diwadkar, Vaibhav A
2016-07-01
Frontal-thalamic interactions are crucial for bottom-up gating and top-down control, yet have not been well studied from brain network perspectives. We applied network modeling of fMRI signals [dynamic causal modeling (DCM)] to investigate frontal-thalamic interactions during an attention task with parametrically varying levels of demand. fMRI was collected while subjects participated in a sustained continuous performance task with low and high attention demands. 162 competing model architectures were employed in DCM to evaluate hypotheses on bilateral frontal-thalamic connections and their modulation by attention demand, selected at a second level using Bayesian model selection. The model architecture evinced significant contextual modulation by attention of ascending (thalamus → dPFC) and descending (dPFC → thalamus) pathways. However, modulation of these pathways was asymmetric: while positive modulation of the ascending pathway was comparable across attention demand, modulation of the descending pathway was significantly greater when attention demands were increased. Increased modulation of the (dPFC → thalamus) pathway in response to increased attention demand constitutes novel evidence of attention-related gain in the connectivity of the descending attention pathway. By comparison demand-independent modulation of the ascending (thalamus → dPFC) pathway suggests unbiased thalamic inputs to the cortex in the context of the paradigm. Hum Brain Mapp 37:2557-2570, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Cantley, Linda F; Tessier-Sherman, Baylah; Slade, Martin D; Galusha, Deron; Cullen, Mark R
2016-01-01
Objective To examine associations between workplace injury and musculoskeletal disorder (MSD) risk and expert ratings of job-level psychosocial demand and job control, adjusting for job-level physical demand. Methods Among a cohort of 9260 aluminium manufacturing workers in jobs for which expert ratings of job-level physical and psychological demand and control were obtained during the 2 years following rating obtainment, multivariate mixed effects models were used to estimate relative risk (RR) of minor injury and minor MSD, serious injury and MSD, minor MSD only and serious MSD only by tertile of demand and control, adjusting for physical demand as well as other recognised risk factors. Results Compared with workers in jobs rated as having low psychological demand, workers in jobs with high psychological demand had 49% greater risk of serious injury and serious MSD requiring medical treatment, work restrictions or lost work time (RR=1.49; 95% CI 1.10 to 2.01). Workers in jobs rated as having low control displayed increased risk for minor injury and minor MSD (RR=1.45; 95% CI 1.12 to 1.87) compared with those in jobs rated as having high control. Conclusions Using expert ratings of job-level exposures, this study provides evidence that psychological job demand and job control contribute independently to injury and MSD risk in a blue-collar manufacturing cohort, and emphasises the importance of monitoring psychosocial workplace exposures in addition to physical workplace exposures to promote worker health and safety. PMID:26163544
Jones, Martyn C; Wells, Mary; Gao, Chuan; Cassidy, Bernadette; Davie, Jackie
2013-01-01
Staff working in oncology report high levels of work-related stress. This arises partly from the nature of clinical work, including practitioner perceptions of high demand and low control or high effort and low reward. This comparative study investigated the correlates of work stress in a multidisciplinary group of staff and the associations between staff perceptions of the work environment, emotional distress, job satisfaction and work-based social support. This questionnaire study combined quantitative and qualitative assessment in a cohort sample of multidisciplinary staff (N = 85) working in a cancer centre in North East Scotland. Ethical approval was granted by the local Research Ethics Committee. This paper reports on the quantitative element of the study, Response rate was 50.6% (N = 85). Older, female and nursing and support staff were more likely to participate. Support staff reported the lowest perceptions of control, job satisfaction and managerial support. Radiographers reported the highest levels of job satisfaction, co-worker and managerial support. Nurses perceived lower decision control and job satisfaction than allied health professionals or doctors. In general, perceptions of decisional control and reward were protective of job satisfaction, particularly when work demands were high. Co-worker support was associated with perceptions of reduced effort, greater reward and increased satisfaction. Managerial support was also associated with greater control beliefs. Overall, sickness absence exceeded the 5% rates seen in other National Health Service surveys, whereas turnover intention rates were similar. The development and introduction of multilevel strategies to reduce demand, improve control and support perceptions are warranted, particularly for support staff. Copyright © 2011 John Wiley & Sons, Ltd.
Detrick, Paul; Chibnall, John T; Call, Cynthia
2010-09-01
Understanding and detecting response distortion is important in the high-demand circumstances of personnel selection. In this article, we describe positive response distortion on the Revised NEO Personality Inventory (NEO PI-R; Costa & McCrae, 1992) among police officer applicants under high and low demand conditions. Positive response distortion primarily reflected denial/minimization of Neuroticism and accentuation of traits associated with moralistic bias (Agreeableness and Conscientiousness). Validity of the NEO PI-R research validity scale, Positive Presentation Management, was weakly supported with respect to the Neuroticism domain only. Results will be useful in interpreting personality inventory results in the police personnel selection process.
van Doorn, Yvonne; van Ruysseveldt, Joris; van Dam, Karen; Mistiaen, Wilhelm; Nikolova, Irina
2016-10-01
This study investigated whether Nigerian nurses' emotional exhaustion and active learning were predicted by job demands, control and social support. Limited research has been conducted concerning nurses' work stress in developing countries, such as Nigeria. Accordingly, it is not clear whether work interventions for improving nurses' well-being in these countries can be based on work stress models that are developed in Western countries, such as the job demand control support model, as well as on empirical findings of job demand control support research. Nurses from Nurses Across the Borders Nigeria were invited to complete an online questionnaire containing validated scales; 210 questionnaires were fully completed and analysed. Multiple regression analysis was used to test the hypotheses. Emotional exhaustion was higher for nurses who experienced high demands and low supervisor support. Active learning occurred when nurses worked under conditions of high control and high supervisor support. The findings suggest that the job demand control support model is applicable in a Nigerian nursing situation; the model indicates which occupational stressors contribute to poor well-being in Nigerian nurses and which work characteristics may boost nurses' active learning. Job (re)design interventions can enhance nurses' well-being and learning by guarding nurses' job demands, and stimulating job control and supervisor support. © 2016 John Wiley & Sons Ltd.
Brain circuitries involved in emotional interference task in major depression disorder.
Chechko, Natalia; Augustin, Marc; Zvyagintsev, Michael; Schneider, Frank; Habel, Ute; Kellermann, Thilo
2013-07-01
Emotional and non-emotional Stroop are frequently applied to study major depressive disorder (MDD). The versions of emotional Stroop used in previous studies were not, unlike the ones employed in the present study, based on semantic incongruence, making it difficult to compare the tasks. We used functional magnetic resonance imaging (fMRI) to study the neural and behavioral responses of 18 healthy subjects and 18 subjects with MDD to emotional and non-emotional word-face Stroop tasks based on semantic incompatibility between targets and distractors. In both groups, the distractors triggered significant amounts of interference conflict. A between-groups comparison revealed hypoactivation in MDD during emotional task in areas supporting conflict resolution (lateral prefrontal cortex, parietal and extrastriate cortices) paralleled by increased response in the right amygdala. Response in the amygdala, however, did not vary between conflicting and non-conflicting trials. While in the emotional (compared to non-emotional) task healthy controls showed considerably stronger involvement of networks related to conflict resolution, in patients, the processing differences between the two conflict types were negligible. The patients group was inhomogeneous in terms of medication and clinical characteristics. The number of female participants was higher, due to which gender effects could not be studied or excluded. Whilst healthy controls seemed able to adjust the involvement of the network supporting conflict resolution based on conflict demand, patients appeared to lack this capability. The reduced cortical involvement coupled with increased response of limbic structures might underlie the maladjustment vis-à-vis new demands in depressed mood. Copyright © 2013 Elsevier B.V. All rights reserved.
Rapid Neocortical Dynamics: Cellular and Network Mechanisms
Haider, Bilal; McCormick, David A.
2011-01-01
The highly interconnected local and large-scale networks of the neocortical sheet rapidly and dynamically modulate their functional connectivity according to behavioral demands. This basic operating principle of the neocortex is mediated by the continuously changing flow of excitatory and inhibitory synaptic barrages that not only control participation of neurons in networks but also define the networks themselves. The rapid control of neuronal responsiveness via synaptic bombardment is a fundamental property of cortical dynamics that may provide the basis of diverse behaviors, including sensory perception, motor integration, working memory, and attention. PMID:19409263
Measurement techniques of LC display systems
NASA Astrophysics Data System (ADS)
Kosmowski, Bogdan B.; Becker, Michael E.; Neumeier, Juergen
1993-10-01
The strong increase of applications of liquid crystal displays in various areas (measuring, medical equipment, automotive, telecommunication, office, etc.) has forced the demand for the adequate specification of the LCDs performances. The optical, electro-optical and spectral properties of LCDs are strongly dependent on viewing direction, electrical driving conditions, illumination and temperature. All these quantities have to be precisely controlled, when one of them is varied, the resulting optical response of the object is recorded. In this paper we present measuring methods proposed for LCD panels and the computer controlled measuring system (DMS) for their evaluation.
Krieger-Redwood, Katya; Teige, Catarina; Davey, James; Hymers, Mark; Jefferies, Elizabeth
2015-09-01
Controlled semantic retrieval to words elicits co-activation of inferior frontal (IFG) and left posterior temporal cortex (pMTG), but research has not yet established (i) the distinct contributions of these regions or (ii) whether the same processes are recruited for non-verbal stimuli. Words have relatively flexible meanings - as a consequence, identifying the context that links two specific words is relatively demanding. In contrast, pictures are richer stimuli and their precise meaning is better specified by their visible features - however, not all of these features will be relevant to uncovering a given association, tapping selection/inhibition processes. To explore potential differences across modalities, we took a commonly-used manipulation of controlled retrieval demands, namely the identification of weak vs. strong associations, and compared word and picture versions. There were 4 key findings: (1) Regions of interest (ROIs) in posterior IFG (BA44) showed graded effects of modality (e.g., words>pictures in left BA44; pictures>words in right BA44). (2) An equivalent response was observed in left mid-IFG (BA45) across modalities, consistent with the multimodal semantic control deficits that typically follow LIFG lesions. (3) The anterior IFG (BA47) ROI showed a stronger response to verbal than pictorial associations, potentially reflecting a role for this region in establishing a meaningful context that can be used to direct semantic retrieval. (4) The left pMTG ROI also responded to difficulty across modalities yet showed a stronger response overall to verbal stimuli, helping to reconcile two distinct literatures that have implicated this site in semantic control and lexical-semantic access respectively. We propose that left anterior IFG and pMTG work together to maintain a meaningful context that shapes ongoing semantic processing, and that this process is more strongly taxed by word than picture associations. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Krieger-Redwood, Katya; Teige, Catarina; Davey, James; Hymers, Mark; Jefferies, Elizabeth
2015-01-01
Controlled semantic retrieval to words elicits co-activation of inferior frontal (IFG) and left posterior temporal cortex (pMTG), but research has not yet established (i) the distinct contributions of these regions or (ii) whether the same processes are recruited for non-verbal stimuli. Words have relatively flexible meanings – as a consequence, identifying the context that links two specific words is relatively demanding. In contrast, pictures are richer stimuli and their precise meaning is better specified by their visible features – however, not all of these features will be relevant to uncovering a given association, tapping selection/inhibition processes. To explore potential differences across modalities, we took a commonly-used manipulation of controlled retrieval demands, namely the identification of weak vs. strong associations, and compared word and picture versions. There were 4 key findings: (1) Regions of interest (ROIs) in posterior IFG (BA44) showed graded effects of modality (e.g., words>pictures in left BA44; pictures>words in right BA44). (2) An equivalent response was observed in left mid-IFG (BA45) across modalities, consistent with the multimodal semantic control deficits that typically follow LIFG lesions. (3) The anterior IFG (BA47) ROI showed a stronger response to verbal than pictorial associations, potentially reflecting a role for this region in establishing a meaningful context that can be used to direct semantic retrieval. (4) The left pMTG ROI also responded to difficulty across modalities yet showed a stronger response overall to verbal stimuli, helping to reconcile two distinct literatures that have implicated this site in semantic control and lexical-semantic access respectively. We propose that left anterior IFG and pMTG work together to maintain a meaningful context that shapes ongoing semantic processing, and that this process is more strongly taxed by word than picture associations. PMID:25726898
A Daily Diary Study of Coping in the Context of the Job Demands-Control-Support Model
ERIC Educational Resources Information Center
Daniels, Kevin; Harris, Claire
2005-01-01
We examined one of the processes thought to underpin Karasek and Theorell's job demands-control-support model (1990). This is that control and support accentuate better well-being by fostering problem-focused coping with work demands. We also examined whether other forms of coping implemented through control and support are related to indicators…
Sex hormones affect language lateralisation but not cognitive control in normally cycling women.
Hodgetts, Sophie; Weis, Susanne; Hausmann, Markus
2015-08-01
This article is part of a Special Issue "Estradiol and Cognition". Natural fluctuations of sex hormones during the menstrual cycle have been shown to modulate language lateralisation. Using the dichotic listening (DL) paradigm, a well-established measurement of language lateralisation, several studies revealed that the left hemispheric language dominance was stronger when levels of estradiol were high. A recent study (Hjelmervik et al., 2012) showed, however, that high levels of follicular estradiol increased lateralisation only in a condition that required participants to cognitively control (top-down) the stimulus-driven (bottom-up) response. This finding suggested that sex hormones modulate lateralisation only if cognitive control demands are high. The present study investigated language lateralisation in 73 normally cycling women under three attention conditions that differed in cognitive control demands. Saliva estradiol and progesterone levels were determined by luminescence immunoassays. Women were allocated to a high or low estradiol group. The results showed a reduced language lateralisation when estradiol and progesterone levels were high. The effect was independent of the attention condition indicating that estradiol marginally affected cognitive control. The findings might suggest that high levels of estradiol especially reduce the stimulus-driven (bottom-up) aspect of lateralisation rather than top-down cognitive control. Copyright © 2015 Elsevier Inc. All rights reserved.
Microgrid Controller and Advanced Distribution Management System Survey Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Guodong; Starke, Michael R.; Herron, Andrew N.
2016-07-01
A microgrid controller, which serves as the heart of a microgrid, is responsible for optimally managing the distributed energy resources, energy storage systems, and responsive demand and for ensuring the microgrid is being operated in an efficient, reliable, and resilient way. As the market for microgrids has blossomed in recently years, many vendors have released their own microgrid controllers to meet the various needs of different microgrid clients. However, due to the absence of a recognized standard for such controllers, vendor-supported microgrid controllers have a range of functionalities that are significantly different from each other in many respects. As amore » result the current state of the industry has been difficult to assess. To remedy this situation the authors conducted a survey of the functions of microgrid controllers developed by vendors and national laboratories. This report presents a clear indication of the state of the microgrid-controller industry based on analysis of the survey results. The results demonstrate that US Department of Energy funded research in microgrid controllers is unique and not competing with that of industry.« less
Neural basis of bilingual language control.
Calabria, Marco; Costa, Albert; Green, David W; Abutalebi, Jubin
2018-06-19
Acquiring and speaking a second language increases demand on the processes of language control for bilingual as compared to monolingual speakers. Language control for bilingual speakers involves the ability to keep the two languages separated to avoid interference and to select one language or the other in a given conversational context. This ability is what we refer with the term "bilingual language control" (BLC). It is now well established that the architecture of this complex system of language control encompasses brain networks involving cortical and subcortical structures, each responsible for different cognitive processes such as goal maintenance, conflict monitoring, interference suppression, and selective response inhibition. Furthermore, advances have been made in determining the overlap between the BLC and the nonlinguistic executive control networks, under the hypothesis that the BLC processes are just an instantiation of a more domain-general control system. Here, we review the current knowledge about the neural basis of these control systems. Results from brain imaging studies of healthy adults and on the performance of bilingual individuals with brain damage are discussed. © 2018 New York Academy of Sciences.
Booranawong, Apidet; Teerapabkajorndet, Wiklom; Limsakul, Chusak
2013-06-27
The main objective of this paper is to investigate the effects of routing protocols on wireless sensor and actuator networks (WSANs), focusing on the control system response and the energy consumption of nodes in a network. We demonstrate that routing algorithms designed without considering the relationship between communication and control cannot be appropriately used in wireless networked control applications. For this purpose, an ad-hoc on-demand distance vector (AODV) routing, an IEEE 802.15.4, and a building-temperature control system are employed for this exploration. The findings from our scenarios show that the AODV routing can select a path with a high traffic load for data transmission. It takes a long time before deciding to change a new route although it experiences the unsuccessful transmission of packets. As a result, the desirable control target cannot be achieved in time, and nodes consume more energy due to frequent packet collisions and retransmissions. Consequently, we propose a simple routing solution to alleviate these research problems by modifying the original AODV routing protocol. The delay-threshold is considered to avoid any congested connection during routing procedures. The simulation results demonstrate that our solution can be appropriately applied in WSANs. Both the energy consumption and the control system response are improved.
Optimal Self-Tuning PID Controller Based on Low Power Consumption for a Server Fan Cooling System.
Lee, Chengming; Chen, Rongshun
2015-05-20
Recently, saving the cooling power in servers by controlling the fan speed has attracted considerable attention because of the increasing demand for high-density servers. This paper presents an optimal self-tuning proportional-integral-derivative (PID) controller, combining a PID neural network (PIDNN) with fan-power-based optimization in the transient-state temperature response in the time domain, for a server fan cooling system. Because the thermal model of the cooling system is nonlinear and complex, a server mockup system simulating a 1U rack server was constructed and a fan power model was created using a third-order nonlinear curve fit to determine the cooling power consumption by the fan speed control. PIDNN with a time domain criterion is used to tune all online and optimized PID gains. The proposed controller was validated through experiments of step response when the server operated from the low to high power state. The results show that up to 14% of a server's fan cooling power can be saved if the fan control permits a slight temperature response overshoot in the electronic components, which may provide a time-saving strategy for tuning the PID controller to control the server fan speed during low fan power consumption.
Work-induced changes in feelings of mastery.
Bradley, Graham L
2010-01-01
Past theory and research indicate that conditions of work can have lasting effects on job incumbents. R. A. Karasek and T. Theorell (1990), for example, proposed that workers' feelings of mastery increase with levels of job demands and job control, and that these effects are mediated by the process of active learning. To test these propositions, 657 school teachers completed scales assessing job demands, control, active learning, and mastery on 2 occasions, 8 months apart. As hypothesized, job control predicted change in mastery, an effect that was mediated by active learning. Job demands had a weaker effect on change in mastery. The demands-mastery relationship was moderated by job control, so that under conditions of high control, but not low control, increasing job demands were associated with gains in mastery. The findings partially support R. A. Karasek and T. Theorell's (1990) predictions regarding the main, interactive, and mediated effects of job conditions on employee mastery.
Making Big Tobacco Give In: You Lose, They Win
Wander, Nathaniel; Malone, Ruth E
2006-01-01
Objectives. To better understand how the tobacco industry responds to tobacco control activists, we explored Philip Morris’s response to demands that consumers in developing countries be informed about smoking risks, and analyzed the implications of negotiating with a tobacco company. Methods. We reviewed internal tobacco industry documents and related materials, constructed a case history of how Philip Morris responded to a shareholder campaign to require health warnings on cigarettes sold worldwide, and analyzed interactions between (1) socially responsible investment activists, (2) Philip Morris management, (3) institutional investors, and (4) industry competitors. Results. After resisting for 11 years, Philip Morris unilaterally reversed direction, and proposed its own labeling initiative. While activists celebrated, Philip Morris’s president detailed privately how the company would yield little and benefit disproportionately. Activists portrayed the tobacco industry as preying on the poor and uneducated and used delegitimization to drive a wedge between the industry and its financial and political allies. When Philip Morris “gave in” to their demands, it exchanged negative publicity for positive public relations and political credibility. Conclusions. Tobacco companies can appear to accommodate public health demands while securing strategic advantages. Negotiating with the tobacco industry can enhance its legitimacy and facilitate its ability to market deadly cigarettes without corresponding benefits to public health. PMID:17018823
Response terminated displays unload selective attention
Roper, Zachary J. J.; Vecera, Shaun P.
2013-01-01
Perceptual load theory successfully replaced the early vs. late selection debate by appealing to adaptive control over the efficiency of selective attention. Early selection is observed unless perceptual load (p-Load) is sufficiently low to grant attentional “spill-over” to task-irrelevant stimuli. Many studies exploring load theory have used limited display durations that perhaps impose artificial limits on encoding processes. We extended the exposure duration in a classic p-Load task to alleviate temporal encoding demands that may otherwise tax mnemonic consolidation processes. If the load effect arises from perceptual demands alone, then freeing-up available mnemonic resources by extending the exposure duration should have little effect. The results of Experiment 1 falsify this prediction. We observed a reliable flanker effect under high p-Load, response-terminated displays. Next, we orthogonally manipulated exposure duration and task-relevance. Counter-intuitively, we found that the likelihood of observing the flanker effect under high p-Load resides with the duration of the task-relevant array, not the flanker itself. We propose that stimulus and encoding demands interact to produce the load effect. Our account clarifies how task parameters differentially impinge upon cognitive processes to produce attentional “spill-over” by appealing to visual short-term memory as an additional processing bottleneck when stimuli are briefly presented. PMID:24399983
Response terminated displays unload selective attention.
Roper, Zachary J J; Vecera, Shaun P
2013-01-01
Perceptual load theory successfully replaced the early vs. late selection debate by appealing to adaptive control over the efficiency of selective attention. Early selection is observed unless perceptual load (p-Load) is sufficiently low to grant attentional "spill-over" to task-irrelevant stimuli. Many studies exploring load theory have used limited display durations that perhaps impose artificial limits on encoding processes. We extended the exposure duration in a classic p-Load task to alleviate temporal encoding demands that may otherwise tax mnemonic consolidation processes. If the load effect arises from perceptual demands alone, then freeing-up available mnemonic resources by extending the exposure duration should have little effect. The results of Experiment 1 falsify this prediction. We observed a reliable flanker effect under high p-Load, response-terminated displays. Next, we orthogonally manipulated exposure duration and task-relevance. Counter-intuitively, we found that the likelihood of observing the flanker effect under high p-Load resides with the duration of the task-relevant array, not the flanker itself. We propose that stimulus and encoding demands interact to produce the load effect. Our account clarifies how task parameters differentially impinge upon cognitive processes to produce attentional "spill-over" by appealing to visual short-term memory as an additional processing bottleneck when stimuli are briefly presented.
Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids.
Pop, Claudia; Cioara, Tudor; Antal, Marcel; Anghel, Ionut; Salomie, Ioan; Bertoncini, Massimo
2018-01-09
In this paper, we investigate the use of decentralized blockchain mechanisms for delivering transparent, secure, reliable, and timely energy flexibility, under the form of adaptation of energy demand profiles of Distributed Energy Prosumers, to all the stakeholders involved in the flexibility markets (Distribution System Operators primarily, retailers, aggregators, etc.). In our approach, a blockchain based distributed ledger stores in a tamper proof manner the energy prosumption information collected from Internet of Things smart metering devices, while self-enforcing smart contracts programmatically define the expected energy flexibility at the level of each prosumer, the associated rewards or penalties, and the rules for balancing the energy demand with the energy production at grid level. Consensus based validation will be used for demand response programs validation and to activate the appropriate financial settlement for the flexibility providers. The approach was validated using a prototype implemented in an Ethereum platform using energy consumption and production traces of several buildings from literature data sets. The results show that our blockchain based distributed demand side management can be used for matching energy demand and production at smart grid level, the demand response signal being followed with high accuracy, while the amount of energy flexibility needed for convergence is reduced.
Method for Estimating Patronage of Demand Responsive Transportation Systems
DOT National Transportation Integrated Search
1977-12-01
This study has developed a method for estimating patronage of demand responsive transportation (DRT) systems. This procedure requires as inputs a description of the intended service area, current work trip patterns, characteristics of the served popu...
DOT National Transportation Integrated Search
1977-04-01
The Urban Mass Transportation Administration carries out research and developmet on Areawide Demand Responsive Transportation (AWDRT) systems as part of the Bus and Paratransit Technoloy activities. AWDRT systems are basically the interation of flexi...
NASA Astrophysics Data System (ADS)
Schmidt, R. D.; Taylor, R. G.; Stodick, L. D.; Contor, B. A.
2009-12-01
A recent federal interagency report on climate change and water management (Brekke et. al., 2009) describes several possible management responses to the impacts of climate change on water supply and demand. Management alternatives include changes to water supply infrastructure, reservoir system operations, and water demand policies. Water users in the Bureau of Reclamation’s Boise Project (located in the Lower Boise River basin in southwestern Idaho) would be among those impacted both hydrologically and economically by climate change. Climate change and management responses to climate change are expected to cause shifts in water supply and demand. Supply shifts would result from changes in basin precipitation patterns, and demand shifts would result from higher evapotranspiration rates and a longer growing season. The impacts would also extend to non-Project water users in the basin, since most non-Project groundwater pumpers and drain water diverters rely on hydrologic externalities created by seepage losses from Boise Project water deliveries. An integrated hydrologic-economic model was developed for the Boise basin to aid Reclamation in evaluating the hydrologic and economic impacts of various management responses to climate change. A spatial, partial-equilibrium, economic optimization model calculates spatially-distinct equilibrium water prices and quantities, and maximizes a social welfare function (the sum of consumer and producers surpluses) for all agricultural and municipal water suppliers and demanders (both Project and non-Project) in the basin. Supply-price functions and demand-price functions are exogenous inputs to the economic optimization model. On the supply side, groundwater and river/reservoir models are used to generate hydrologic responses to various management alternatives. The response data is then used to develop water supply-price functions for Project and non-Project water users. On the demand side, crop production functions incorporating crop distribution, evapotranspiration rates, irrigation efficiencies, and crop prices are used to develop water demand-price functions for agricultural water users. Demand functions for municipal and industrial water users are also developed. Recent applications of the integrated model have focused on the hydrologic and economic impacts of demand management alternatives, including large-scale canal lining conservation measures, and market-based water trading between canal diverters and groundwater pumpers. A supply management alternative being investigated involves revising reservoir rule curves to compensate for climate change impacts on timing of reservoir filling.
The Focusing of Responsibility: An Alternative Hypothesis in Help-Demanding Situations.
ERIC Educational Resources Information Center
Misavage, Robert; Richardson, James T.
The "diffusion of responsibility" hypothesis as an explanation of helping behavior (or lack of same) is qualified by suggesting that the hypothesis applies only in non-interacting situations. It is hypothesized that interacting groups who are aware of a help-demanding situation actually focus the responsibility and, therefore, take action as a…
Cut Electric Bills by Controlling Demand
ERIC Educational Resources Information Center
Grumman, David L.
1974-01-01
Electric bills can be reduced by lowering electric consumption and by controlling demand -- the amount of electricity used at a certain point in time. Gives tips to help reduce electric demand at peak power periods. (Author/DN)
Lornudd, Caroline; Tafvelin, Susanne; von Thiele Schwarz, Ulrica; Bergman, David
2015-02-01
The relationship between leadership and employee distress is well established, however, the processes involved in this relationship remain largely unclear. For a stretched nursing workforce, understanding in what ways leadership may influence employee distress is particularly important. To examine possible mediating effects of the work environment factors demand and control in the relationship between leadership behaviour in change, production, and employee orientation and employee distress. Cross-sectional study design. The study was conducted at a large county council in Sweden providing both institutional and non-institutional care. A random sample of 1249 employees (primarily nurses, but also a wide range of other healthcare professionals and administrative staff), who had a healthcare manager that was about to enter a leadership development programme (n=171), responded to a web-based questionnaire. The response rate was 62%. The employees rated their healthcare managers' behaviour in change, production, and employee orientation, as well as their own perceptions of level of demand, control (subdivided into decision authority and skill discretion), and five distress outcomes. Multilevel analysis was performed. The mediators demand, decision authority, and skill discretion were significant predictors of all five distress outcomes for all three leadership orientations. In eight of 15 regressions, the mediators fully explained the relationships between leadership orientations and outcomes. Four of five relationships with distress outcomes were fully mediated for change-oriented leadership, whereas two of five outcomes were fully mediated for production- and employee-oriented leadership. In all three leadership orientations, the relationship between the mediator skill discretion and the distress measure disengagement were particularly strong, with B-coefficients (-.44, p<.001) twice as high as for any of the other relationships. It seems that the way that employees perceive healthcare managers' change-oriented behaviour, and how that aspect is related to employee distress, is primarily explained by perception of demand and control. Furthermore, regardless of leadership behaviour orientation, how employees perceive their opportunity to use specific job skills plays an important role in the interplay between perception of healthcare managers' behaviour and disengagement. Copyright © 2014 Elsevier Ltd. All rights reserved.
Manigault, Andrew W; Woody, Alex; Zoccola, Peggy M; Dickerson, Sally S
2018-05-21
Researchers benefit from controlling for individual differences that systematically account for variance in acute cortisol responses (e.g., sex). Similarly, some suggest that education could be used as a cortisol covariate because prior work found a negative relationship between education and the magnitude of acute cortisol responses in middle-aged adults. Nevertheless, education is seldom controlled for in tests of cortisol responses to acute stress, in part because the effect of education on acute cortisol responses has yet to be tested in a college sample. The present study therefore tested the relationship between education and cortisol responses to acute stress in college students. Participants (124 healthy undergraduate students) self-reported education level and were subjected to a stressful speech task. Salivary cortisol was collected 0, + 15, + 25, + 40, and + 55 min post-stressor onset. Participant also completed a battery of questionnaires assessing individual differences, day-to-day demands, and stress-related appraisals. Students in their fourth year of college education or above had significantly less curvilinear responses to the stress task relative to first-, second-, and third-year students. The effect of education on cortisol responses previously found in middle-aged adults was replicated in college students. Future research may therefore benefit from controlling for education when analyzing acute cortisol responses in college samples.
Family nursing hospital training and the outcome on job demands, control and support.
Sigurdardottir, Anna Olafia; Svavarsdottir, Erla Kolbrun; Juliusdottir, Sigrun
2015-07-01
The purpose of this study was to evaluate the impact of a family systems nursing hospital training educational program (ETI program) on nurses' and midwives' perception of job demands, control, and/or support. Of the nurses and midwives who were working in the Women's and Children's Services Division at The National University Hospital in Iceland, 479 participated in the study on three time periods from 2009 to 2011. Scores for the characteristics of job demands and job control were created to categorize participants into four job types (Karasek and Theorell, 1990). These four job types are high strain (high demand, low control), passive (low demand, low control), low strain (low demand, high control), and active (high demand, high control). However, when the data were evaluated based on the proportion of job characteristics as reported by the nurses and the midwives, no significant difference was found over time (2009 to 2011) (χ(2)=5.203, p=.518). However, based on the results from the independent t-tests at time 1, a significant difference was found amongst the high strain job group regarding perceived support from administrators and colleagues among the nurses and midwives who had taken the ETI program compared to those who had not taken the program (χ(2)=2.218, p=.034). This indicates that the health care professionals who characterized their job to be of high demand but with low control evaluated the support from their administrators and colleagues to be significantly higher if they had taken the ETI program than did the nurses and midwives who did not take the ETI program. These findings are promising because they might, in the long run, increase the nurses' and midwives' autonomy and control over their own work. Copyright © 2015 Elsevier Ltd. All rights reserved.
Photoperiodic Control of Carbon Distribution during the Floral Transition in Arabidopsis[C][W][OPEN
Ortiz-Marchena, M. Isabel; Albi, Tomás; Lucas-Reina, Eva; Said, Fatima E.; Romero-Campero, Francisco J.; Cano, Beatriz; Ruiz, M. Teresa; Romero, José M.; Valverde, Federico
2014-01-01
Flowering is a crucial process that demands substantial resources. Carbon metabolism must be coordinated with development through a control mechanism that optimizes fitness for any physiological need and growth stage of the plant. However, how sugar allocation is controlled during the floral transition is unknown. Recently, the role of a CONSTANS (CO) ortholog (Cr-CO) in the control of the photoperiod response in the green alga Chlamydomonas reinhardtii and its influence on starch metabolism was demonstrated. In this work, we show that transitory starch accumulation and glycan composition during the floral transition in Arabidopsis thaliana are regulated by photoperiod. Employing a multidisciplinary approach, we demonstrate a role for CO in regulating the level and timing of expression of the GRANULE BOUND STARCH SYNTHASE (GBSS) gene. Furthermore, we provide a detailed characterization of a GBSS mutant involved in transitory starch synthesis and analyze its flowering time phenotype in relation to its altered capacity to synthesize amylose and to modify the plant free sugar content. Photoperiod modification of starch homeostasis by CO may be crucial for increasing the sugar mobilization demanded by the floral transition. This finding contributes to our understanding of the flowering process. PMID:24563199
pH Responsive Microcapsules for Corrosion Control
NASA Technical Reports Server (NTRS)
Calle, Luz Marina; Li, Wenyan; Muehlberg, Aaron; Boraas, Samuel; Webster, Dean; JohnstonGelling, Victoria; Croll, Stuart; Taylor, S Ray; Contu, Francesco
2008-01-01
The best coatings for corrosion protection provide not only barriers to the environment, but also a controlled release of a corrosion inhibitor, as demanded by the presence of corrosion or mechanical damage. NASA has developed pH sensitive microcapsules (patent pending) that can release their core contents when corrosion starts. The objectives of the research presented here were to encapsulate non-toxic corrosion inhibitors, to incorporate the encapsulated inhibitors into paint formulations, and to test the ability of the paints to control corrosion. Results showed that the encapsulated corrosion inhibitors, specifically Ce(NO3)3 , are effective to control corrosion over long periods of time when incorporated at relatively high pigment volume concentrations into a paint formulation.
Agent-Based Simulation for Interconnection-Scale Renewable Integration and Demand Response Studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chassin, David P.; Behboodi, Sahand; Crawford, Curran
This paper collects and synthesizes the technical requirements, implementation, and validation methods for quasi-steady agent-based simulations of interconnectionscale models with particular attention to the integration of renewable generation and controllable loads. Approaches for modeling aggregated controllable loads are presented and placed in the same control and economic modeling framework as generation resources for interconnection planning studies. Model performance is examined with system parameters that are typical for an interconnection approximately the size of the Western Electricity Coordinating Council (WECC) and a control area about 1/100 the size of the system. These results are used to demonstrate and validate the methodsmore » presented.« less
Agent-Based Simulation for Interconnection-Scale Renewable Integration and Demand Response Studies
Chassin, David P.; Behboodi, Sahand; Crawford, Curran; ...
2015-12-23
This paper collects and synthesizes the technical requirements, implementation, and validation methods for quasi-steady agent-based simulations of interconnectionscale models with particular attention to the integration of renewable generation and controllable loads. Approaches for modeling aggregated controllable loads are presented and placed in the same control and economic modeling framework as generation resources for interconnection planning studies. Model performance is examined with system parameters that are typical for an interconnection approximately the size of the Western Electricity Coordinating Council (WECC) and a control area about 1/100 the size of the system. These results are used to demonstrate and validate the methodsmore » presented.« less
Taylor, Ronald D; Budescu, Mia
2013-01-01
Association of mothers' emotional adjustment and negative kin relations with distressed interpersonal relations was examined. Among 115 low-income African American mothers, relationship of depressive symptoms, self-esteem, and demanding kin relations with psychological control and stressful interpersonal relations was assessed. Depressive symptoms and demanding kin relations were positively associated with mothers' use of psychological control in parenting. Interaction of self-esteem with demanding kin relations revealed that self-esteem was negatively associated with psychological control for mothers with high-demanding kin relations but not for mothers with low-demanding kin relations. Mothers' depressive symptoms and demanding kin relations were positively associated with their stressful interpersonal relations. Findings were discussed in terms of the need for research on the beneficial and detrimental aspects of families' social network.
Modeling, Analysis, and Control of Demand Response Resources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mathieu, Johanna L.
2012-05-01
While the traditional goal of an electric power system has been to control supply to fulfill demand, the demand-side can plan an active role in power systems via Demand Response (DR), defined by the Department of Energy (DOE) as “a tariff or program established to motivate changes in electric use by end-use customers in response to changes in the price of electricity over time, or to give incentive payments designed to induce lower electricity use at times of high market prices or when grid reliability is jeopardized” [29]. DR can provide a variety of benefits including reducing peak electric loadsmore » when the power system is stressed and fast timescale energy balancing. Therefore, DR can improve grid reliability and reduce wholesale energy prices and their volatility. This dissertation focuses on analyzing both recent and emerging DR paradigms. Recent DR programs have focused on peak load reduction in commercial buildings and industrial facilities (C&I facilities). We present methods for using 15-minute-interval electric load data, commonly available from C&I facilities, to help building managers understand building energy consumption and ‘ask the right questions’ to discover opportunities for DR. Additionally, we present a regression-based model of whole building electric load, i.e., a baseline model, which allows us to quantify DR performance. We use this baseline model to understand the performance of 38 C&I facilities participating in an automated dynamic pricing DR program in California. In this program, facilities are expected to exhibit the same response each DR event. We find that baseline model error makes it difficult to precisely quantify changes in electricity consumption and understand if C&I facilities exhibit event-to-event variability in their response to DR signals. Therefore, we present a method to compute baseline model error and a metric to determine how much observed DR variability results from baseline model error rather than real variability in response. We find that, in general, baseline model error is large. Though some facilities exhibit real DR variability, most observed variability results from baseline model error. In some cases, however, aggregations of C&I facilities exhibit real DR variability, which could create challenges for power system operation. These results have implications for DR program design and deployment. Emerging DR paradigms focus on faster timescale DR. Here, we investigate methods to coordinate aggregations of residential thermostatically controlled loads (TCLs), including air conditioners and refrigerators, to manage frequency and energy imbalances in power systems. We focus on opportunities to centrally control loads with high accuracy but low requirements for sensing and communications infrastructure. Specifically, we compare cases when measured load state information (e.g., power consumption and temperature) is 1) available in real time; 2) available, but not in real time; and 3) not available. We develop Markov Chain models to describe the temperature state evolution of heterogeneous populations of TCLs, and use Kalman filtering for both state and joint parameter/state estimation. We present a look-ahead proportional controller to broadcast control signals to all TCLs, which always remain in their temperature dead-band. Simulations indicate that it is possible to achieve power tracking RMS errors in the range of 0.26–9.3% of steady state aggregated power consumption. Results depend upon the information available for system identification, state estimation, and control. We find that, depending upon the performance required, TCLs may not need to provide state information to the central controller in real time or at all. We also estimate the size of the TCL potential resource; potential revenue from participation in markets; and break-even costs associated with deploying DR-enabling technologies. We find that current TCL energy storage capacity in California is 8–11 GWh, with refrigerators contributing the most. Annual revenues from participation in regulation vary from $10 to $220 per TCL per year depending upon the type of TCL and climate zone, while load following and arbitrage revenues are more modest at $2 to $35 per TCL per year. These results lead to a number of policy recommendations that will make it easier to engage residential loads in fast timescale DR.« less
22 CFR 1506.5 - Demand for payment.
Code of Federal Regulations, 2010 CFR
2010-04-01
... total of three progressively stronger written demands at approximately 30-day intervals will normally be made, unless a response or other information indicates that additional written demands would either be unnecessary or futile. When necessary to protect the Government's interest, written demand may be preceded by...
Results of an integrated structure-control law design sensitivity analysis
NASA Technical Reports Server (NTRS)
Gilbert, Michael G.
1988-01-01
Next generation air and space vehicle designs are driven by increased performance requirements, demanding a high level of design integration between traditionally separate design disciplines. Interdisciplinary analysis capabilities have been developed, for aeroservoelastic aircraft and large flexible spacecraft control for instance, but the requisite integrated design methods are only beginning to be developed. One integrated design method which has received attention is based on hierarchal problem decompositions, optimization, and design sensitivity analyses. This paper highlights a design sensitivity analysis method for Linear Quadratic Cost, Gaussian (LQG) optimal control laws, which predicts change in the optimal control law due to changes in fixed problem parameters using analytical sensitivity equations. Numerical results of a design sensitivity analysis for a realistic aeroservoelastic aircraft example are presented. In this example, the sensitivity of the optimally controlled aircraft's response to various problem formulation and physical aircraft parameters is determined. These results are used to predict the aircraft's new optimally controlled response if the parameter was to have some other nominal value during the control law design process. The sensitivity results are validated by recomputing the optimal control law for discrete variations in parameters, computing the new actual aircraft response, and comparing with the predicted response. These results show an improvement in sensitivity accuracy for integrated design purposes over methods which do not include changess in the optimal control law. Use of the analytical LQG sensitivity expressions is also shown to be more efficient that finite difference methods for the computation of the equivalent sensitivity information.
Berntsson, L; Lundberg, U; Krantz, G
2006-01-01
Objective To analyse gender differences in paid and unpaid workload and symptoms in matched groups of Swedish white‐collar workers with children. Design and setting Paid and unpaid workload and perceived stress from paid work, conflict between demands and control over household work were measured by a total workload (TWL) questionnaire. Some symptoms were rated with regard to frequency and severity as a measure of health. Cross‐sectional analyses were performed. Participants Matched groups of male (n = 440) and female (n = 529) well‐educated white‐collar workers in full‐time employment, aged 32–58 years and living with children in the home. Results Women in higher positions in Sweden are healthier than the average population of women, but report more symptoms than men in the same position as well as more stress from paid work, more conflict between demands and a greater TWL. However, women also reported more control over household duties and TWL was not associated with more symptoms. The men were mainly focused on their paid work role and perhaps even more so than men in the general population as they were fairly resistant to feelings of conflicting demands. Conclusion Even among matched groups of full‐time employed, well‐educated men and women, traditional gender differences in division of responsibilities and time allocation were found. Even though the women were healthy at this stage, they might risk future ill health, owing to high workload, stress and feelings of conflicting demands. PMID:17108304
Berntsson, L; Lundberg, U; Krantz, G
2006-12-01
To analyse gender differences in paid and unpaid workload and symptoms in matched groups of Swedish white-collar workers with children. Paid and unpaid workload and perceived stress from paid work, conflict between demands and control over household work were measured by a total workload (TWL) questionnaire. Some symptoms were rated with regard to frequency and severity as a measure of health. Cross-sectional analyses were performed. Matched groups of male (n = 440) and female (n = 529) well-educated white-collar workers in full-time employment, aged 32-58 years and living with children in the home. Women in higher positions in Sweden are healthier than the average population of women, but report more symptoms than men in the same position as well as more stress from paid work, more conflict between demands and a greater TWL. However, women also reported more control over household duties and TWL was not associated with more symptoms. The men were mainly focused on their paid work role and perhaps even more so than men in the general population as they were fairly resistant to feelings of conflicting demands. Even among matched groups of full-time employed, well-educated men and women, traditional gender differences in division of responsibilities and time allocation were found. Even though the women were healthy at this stage, they might risk future ill health, owing to high workload, stress and feelings of conflicting demands.
Mehta, Ranjana K; Agnew, Michael J
2012-08-01
Most occupational tasks involve some level of mental/cognitive processing in addition to physical work; however, the etiology of work-related musculoskeletal disorders (WMSDs) due to these demands remains unclear. The aim of this study was to quantify the interactive effects of physical and mental workload on muscle endurance, fatigue, and recovery during intermittent work. Twelve participants, balanced by gender, performed intermittent static shoulder abductions to exhaustion at 15, 35, and 55% of individual maximal voluntary contraction (MVC), in the absence (control) and presence (concurrent) of a mental arithmetic task. Changes in muscular capacity were determined using endurance time, strength decline, electromyographic (EMG) fatigue indicators, muscle oxygenation, and heart rate measures. Muscular recovery was quantified through changes in strength and physiological responses. Mental workload was associated with shorter endurance times, specifically at 35% MVC, and greater strength decline. EMG and oxygenation measures showed similar changes during fatigue manifestation during concurrent conditions compared to the control, despite shorter endurance times. Moreover, decreased heart rate variability during concurrent demand conditions indicated increased mental stress. Although strength recovery was not influenced by mental workload, a slower heart rate recovery was observed after concurrent demand conditions. The findings from this study provide fundamental evidence that physical capacity (fatigability and recovery) is adversely affected by mental workload. Thus, it is critical to determine or evaluate occupational demands based on modified muscular capacity (due to mental workload) to reduce risk of WMSD development.
Cantley, Linda F; Tessier-Sherman, Baylah; Slade, Martin D; Galusha, Deron; Cullen, Mark R
2016-04-01
To examine associations between workplace injury and musculoskeletal disorder (MSD) risk and expert ratings of job-level psychosocial demand and job control, adjusting for job-level physical demand. Among a cohort of 9260 aluminium manufacturing workers in jobs for which expert ratings of job-level physical and psychological demand and control were obtained during the 2 years following rating obtainment, multivariate mixed effects models were used to estimate relative risk (RR) of minor injury and minor MSD, serious injury and MSD, minor MSD only and serious MSD only by tertile of demand and control, adjusting for physical demand as well as other recognised risk factors. Compared with workers in jobs rated as having low psychological demand, workers in jobs with high psychological demand had 49% greater risk of serious injury and serious MSD requiring medical treatment, work restrictions or lost work time (RR=1.49; 95% CI 1.10 to 2.01). Workers in jobs rated as having low control displayed increased risk for minor injury and minor MSD (RR=1.45; 95% CI 1.12 to 1.87) compared with those in jobs rated as having high control. Using expert ratings of job-level exposures, this study provides evidence that psychological job demand and job control contribute independently to injury and MSD risk in a blue-collar manufacturing cohort, and emphasises the importance of monitoring psychosocial workplace exposures in addition to physical workplace exposures to promote worker health and safety. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Fransson, Eleonor I; Nyberg, Solja T; Heikkilä, Katriina; Alfredsson, Lars; Bacquer, De Dirk; Batty, G David; Bonenfant, Sébastien; Casini, Annalisa; Clays, Els; Goldberg, Marcel; Kittel, France; Koskenvuo, Markku; Knutsson, Anders; Leineweber, Constanze; Magnusson Hanson, Linda L; Nordin, Maria; Singh-Manoux, Archana; Suominen, Sakari; Vahtera, Jussi; Westerholm, Peter; Westerlund, Hugo; Zins, Marie; Theorell, Töres; Kivimäki, Mika
2012-01-20
Job strain (i.e., high job demands combined with low job control) is a frequently used indicator of harmful work stress, but studies have often used partial versions of the complete multi-item job demands and control scales. Understanding whether the different instruments assess the same underlying concepts has crucial implications for the interpretation of findings across studies, harmonisation of multi-cohort data for pooled analyses, and design of future studies. As part of the 'IPD-Work' (Individual-participant-data meta-analysis in working populations) consortium, we compared different versions of the demands and control scales available in 17 European cohort studies. Six of the 17 studies had information on the complete scales and 11 on partial scales. Here, we analyse individual level data from 70 751 participants of the studies which had complete scales (5 demand items, 6 job control items). We found high Pearson correlation coefficients between complete scales of job demands and control relative to scales with at least three items (r > 0.90) and for partial scales with two items only (r = 0.76-0.88). In comparison with scores from the complete scales, the agreement between job strain definitions was very good when only one item was missing in either the demands or the control scale (kappa > 0.80); good for job strain assessed with three demand items and all six control items (kappa > 0.68) and moderate to good when items were missing from both scales (kappa = 0.54-0.76). The sensitivity was > 0.80 when only one item was missing from either scale, decreasing when several items were missing in one or both job strain subscales. Partial job demand and job control scales with at least half of the items of the complete scales, and job strain indices based on one complete and one partial scale, seemed to assess the same underlying concepts as the complete survey instruments.
2012-01-01
Background Job strain (i.e., high job demands combined with low job control) is a frequently used indicator of harmful work stress, but studies have often used partial versions of the complete multi-item job demands and control scales. Understanding whether the different instruments assess the same underlying concepts has crucial implications for the interpretation of findings across studies, harmonisation of multi-cohort data for pooled analyses, and design of future studies. As part of the 'IPD-Work' (Individual-participant-data meta-analysis in working populations) consortium, we compared different versions of the demands and control scales available in 17 European cohort studies. Methods Six of the 17 studies had information on the complete scales and 11 on partial scales. Here, we analyse individual level data from 70 751 participants of the studies which had complete scales (5 demand items, 6 job control items). Results We found high Pearson correlation coefficients between complete scales of job demands and control relative to scales with at least three items (r > 0.90) and for partial scales with two items only (r = 0.76-0.88). In comparison with scores from the complete scales, the agreement between job strain definitions was very good when only one item was missing in either the demands or the control scale (kappa > 0.80); good for job strain assessed with three demand items and all six control items (kappa > 0.68) and moderate to good when items were missing from both scales (kappa = 0.54-0.76). The sensitivity was > 0.80 when only one item was missing from either scale, decreasing when several items were missing in one or both job strain subscales. Conclusions Partial job demand and job control scales with at least half of the items of the complete scales, and job strain indices based on one complete and one partial scale, seemed to assess the same underlying concepts as the complete survey instruments. PMID:22264402
The host immune response to gastrointestinal nematode infection in sheep.
McRae, K M; Stear, M J; Good, B; Keane, O M
2015-12-01
Gastrointestinal nematode infection represents a major threat to the health, welfare and productivity of sheep populations worldwide. Infected lambs have a reduced ability to absorb nutrients from the gastrointestinal tract, resulting in morbidity and occasional mortality. The current chemo-dominant approach to nematode control is considered unsustainable due to the increasing incidence of anthelmintic resistance. In addition, there is growing consumer demand for food products from animals not subjected to chemical treatment. Future mechanisms of nematode control must rely on alternative, sustainable strategies such as vaccination or selective breeding of resistant animals. Such strategies take advantage of the host's natural immune response to nematodes. The ability to resist gastrointestinal nematode infection is considered to be dependent on the development of a protective acquired immune response, although the precise immune mechanisms involved in initiating this process remain to be fully elucidated. In this study, current knowledge on the innate and acquired host immune response to gastrointestinal nematode infection in sheep and the development of immunity is reviewed. © 2015 John Wiley & Sons Ltd.
Recent Advances in Stimuli-Responsive Release Function Drug Delivery Systems for Tumor Treatment.
Ding, Chendi; Tong, Ling; Feng, Jing; Fu, Jiajun
2016-12-20
Benefiting from the development of nanotechnology, drug delivery systems (DDSs) with stimuli-responsive controlled release function show great potential in clinical anti-tumor applications. By using a DDS, the harsh side effects of traditional anti-cancer drug treatments and damage to normal tissues and organs can be avoided to the greatest extent. An ideal DDS must firstly meet bio-safety standards and secondarily the efficiency-related demands of a large drug payload and controlled release function. This review highlights recent research progress on DDSs with stimuli-responsive characteristics. The first section briefly reviews the nanoscale scaffolds of DDSs, including mesoporous nanoparticles, polymers, metal-organic frameworks (MOFs), quantum dots (QDs) and carbon nanotubes (CNTs). The second section presents the main types of stimuli-responsive mechanisms and classifies these into two categories: intrinsic (pH, redox state, biomolecules) and extrinsic (temperature, light irradiation, magnetic field and ultrasound) ones. Clinical applications of DDS, future challenges and perspectives are also mentioned.
AuBuchon, Angela M.; Pisoni, David B.; Kronenberger, William G.
2015-01-01
OBJECTIVES Determine if early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated. DESIGN Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions which differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing). RESULTS Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response. CONCLUSIONS Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory utilizing phonological and linguistic strategies during memory tasks. PMID:26496666
AuBuchon, Angela M; Pisoni, David B; Kronenberger, William G
2015-01-01
To determine whether early-implanted, long-term cochlear implant (CI) users display delays in verbal short-term and working memory capacity when processes related to audibility and speech production are eliminated. Twenty-three long-term CI users and 23 normal-hearing controls each completed forward and backward digit span tasks under testing conditions that differed in presentation modality (auditory or visual) and response output (spoken recall or manual pointing). Normal-hearing controls reproduced more lists of digits than the CI users, even when the test items were presented visually and the responses were made manually via touchscreen response. Short-term and working memory delays observed in CI users are not due to greater demands from peripheral sensory processes such as audibility or from overt speech-motor planning and response output organization. Instead, CI users are less efficient at encoding and maintaining phonological representations in verbal short-term memory using phonological and linguistic strategies during memory tasks.
Sex and race differences in young people's responsiveness to price and tobacco control policies
Chaloupka, F.; Pacula, R. L.
1999-01-01
OBJECTIVE—To determine if there are differences in young people's responsiveness to price and tobacco control policies for population subgroups and to examine whether or not these differences, if they exist, can explain sex and racial differences in trends in the prevalence of smoking in young people in the United States. DESIGN—Use cross-sectional and intertemporal variation in local and state tobacco control policies and prices to calculate demand responses to these policies using regression analysis techniques. SUBJECTS—A nationally representative sample of American eighth grade (ages 13-14 years), 10th grade (15-16 years) and 12th grade (17-18 years) students obtained from the 1992-1994 Monitoring the Future surveys. MAIN OUTCOME MEASURE—Thirty-day smoking prevalence. RESULTS—Young men are much more responsive to changes in the price of cigarettes than young women. The prevalence elasticity for young men is almost twice as large as that for young women. Smoking rates of young black men are significantly more responsive to changes in price than young white men. Significant differences in responsiveness to particular tobacco control policies also exist. These differences, however, explain relatively little of the differences in smoking prevalence among young population subgroups. CONCLUSIONS—Policymakers need to keep in mind that there is not a "one-size fits all" strategy for discouraging smoking among young people. Keywords: adolescents; tobacco control policies; price; sex differences; racial differences PMID:10629242
Distraction decreases prefrontal oxygenation: A NIRS study.
Ozawa, Sachiyo; Hiraki, Kazuo
2017-04-01
When near-infrared spectroscopy (NIRS) is used to measure emotion-related cerebral blood flow (CBF) changes in the prefrontal cortex regions, the functional distinction of CBF changes is often difficult because NIRS is unable to measure neural activity in deeper brain regions that play major roles in emotional processing. The CBF changes could represent cognitive control of emotion and emotional responses to emotional materials. Supposing that emotion-related CBF changes in the prefrontal cortex regions during distraction are emotional responses, we examined whether oxygenated hemoglobin (oxyHb) decreases. Attention-demanding tasks cause blood flow decreases, and we thus compared the effects of visually paced tapping with different tempos, on distraction. The results showed that the oxyHb level induced by emotional stimulation decreased with fast-tempo tapping significantly more than slow-tempo tapping in ventral medial prefrontal cortex regions. Moreover, a Global-Local task following tapping showed significantly greater local-minus-global response time (RT) difference scores in the fast- and mid-tempo condition compared with those in the slow-tempo, suggesting an increased attentional focus, and decreased negative emotion. The overall findings indicate that oxyHb changes in a relatively long distraction task, as measured by NIRS, are associated with emotional responses, and oxyHb can be decreased by successfully performing attention-demanding distraction tasks. Copyright © 2017 Elsevier Inc. All rights reserved.
Zhou, Weibin; Moguche, Albanus O; Chiu, David; Murali-Krishna, Kaja; Baneyx, François
2014-04-01
Distributed and on-demand vaccine production could be game-changing for infectious disease treatment in the developing world by providing new therapeutic opportunities and breaking the refrigeration "cold chain". Here, we show that a fusion protein between a calcium phosphate binding domain and the model antigen ovalbumin can mineralize a biocompatible adjuvant in a single step. The resulting 50 nm calcium phosphate core-immunogen shell particles are comparable to soluble protein in inducing ovalbumin-specific antibody response and class switch recombination in mice. However, single dose vaccination with nanoparticles leads to higher expansion of ovalbumin-specific CD8(+) T cells upon challenge with an influenza virus bearing the ovalbumin-derived SIINFEKL peptide, and these cells produce high levels of IFN-γ. Furthermore, mice exhibit a robust antigen-specific CD8(+) T cell recall response when challenged with virus 8 months post-immunization. These results underscore the promise of immunogen-controlled adjuvant mineralization for just-in-time manufacturing of effective T cell vaccines. This paper reports that a fusion protein between a calcium phosphate binding domain and the model antigen ovalbumin can mineralize into a biocompatible adjuvant in a single step, enabling distributed and on-demand vaccine production and eliminating the need for refrigeration of vaccines. The findings highlight the possibility of immunogen-controlled adjuvant mineralization for just-in-time manufacturing of effective T cell vaccines. Copyright © 2014 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Ribeiro Neto, A.; Scott, C. A.; Lima, E. A.; Montenegro, S. M. G. L.; Cirilo, J. A.
2014-09-01
Water availability for a range of human uses will increasingly be affected by climate change, especially in the arid and semiarid tropics. The main objective of this study is to evaluate the infrastructure sufficiency in meeting water demand under climate-induced socio-hydrological transition in the Capibaribe River basin (CRB). The basin has experienced spatial and sectoral (agriculture-to-urban) reconfiguration of water demands. Human settlements that were once dispersed, relying on intermittent sources of surface water, are now larger and more spatially concentrated, which increases water-scarcity effects. Based on the application of linked hydrologic and water-resources models using precipitation and temperature projections of the IPCC SRES (Special Report: Emissions Scenarios) A1B scenario, a reduction in rainfall of 26.0% translated to streamflow reduction of 60.0%. We used simulations from four members of the HadCM3 (UK Met Office Hadley Centre) perturbed physics ensemble, in which a single model structure is used and perturbations are introduced to the physical parameterization schemes in the model (Chou et al., 2012). We considered that the change of the water availability in the basin in the future scenarios must drive the water management and the development of adaptation strategies that will manage the water demand. Several adaptive responses are considered, including water-loss reductions, wastewater collection and reuse, and rainwater collection cisterns, which together have potential to reduce future water demand by 23.0%. This study demonstrates the vulnerabilities of the infrastructure system during socio-hydrological transition in response to hydroclimatic and demand variabilities in the CRB and also indicates the differential spatial impacts and vulnerability of multiple uses of water to changes over time. The simulations showed that the measures proposed and the water from interbasin transfer project of the São Francisco River had a positive impact over the water supply in the basin, mainly for human use. Industry and irrigation will suffer impact unless other measures are implemented for demand control.
de Lange, Annet H; Kompier, Michiel A J; Taris, Toon W; Geurts, Sabine A E; Beckers, Debby G J; Houtman, Irene L D; Bongers, Paulien M
2009-09-01
This prospective four-wave study examined (i) the causal direction of the longitudinal relations among job demands, job control, sleep quality and fatigue; and (ii) the effects of stability and change in demand-control history on the development of sleep quality and fatigue. Based on results of a four-wave complete panel study among 1163 Dutch employees, we found significant effects of job demands and job control on sleep quality and fatigue across a 1-year time lag, supporting the strain hypothesis (Demand-Control model; Karasek and Theorell, Basic Books, New York, 1990). No reversed or reciprocal causal patterns were detected. Furthermore, our results revealed that cumulative exposure to a high-strain work environment (characterized by high job demands and low job control) was associated with elevated levels of sleep-related complaints. Cumulative exposure to a low-strain work environment (i.e. low job demands and high job control) was associated with the highest sleep quality and lowest level of fatigue. Our results revealed further that changes in exposure history were related to changes in reported sleep quality and fatigue across time. As expected, a transition from a non-high-strain towards a high-strain job was associated with a significant increase in sleep-related complaints; conversely, a transition towards a non-high-strain job was not related to an improvement in sleep-related problems.
Scott, Rose M; Roby, Erin
2015-01-01
Prior to age four, children succeed in non-elicited-response false-belief tasks but fail elicited-response false-belief tasks. To explain this discrepancy, the processing-load account argues that the capacity to represent beliefs emerges in infancy, as indicated by early success on non-elicited-response tasks, but that children's ability to demonstrate this capacity depends on the processing demands of the task and children's processing skills. When processing demands exceed young children's processing abilities, such as in standard elicited-response tasks, children fail despite their capacity to represent beliefs. Support for this account comes from recent evidence that reducing processing demands improves young children's performance: when demands are sufficiently reduced, 2.5-year-olds succeed in elicited-response tasks. Here we sought complementary evidence for the processing-load account by examining whether increasing processing demands impeded children's performance in a non-elicited-response task. 3-year-olds were tested in a preferential-looking task in which they heard a change-of-location false-belief story accompanied by a picture book; across children, we manipulated the amount of linguistic ambiguity in the story. The final page of the book showed two images: one that was consistent with the main character's false belief and one that was consistent with reality. When the story was relatively unambiguous, children looked reliably longer at the false-belief-consistent image, successfully demonstrating their false-belief understanding. When the story was ambiguous, however, this undermined children's performance: looking times to the belief-consistent image were correlated with verbal ability, and only children with verbal skills in the upper quartile of the sample demonstrated a significant preference for the belief-consistent image. These results support the processing-load account by demonstrating that regardless of whether a task involves an elicited response, children's performance depends on the processing demands of the task and their processing skills. These findings also have implications for alternative, deflationary accounts of early false-belief understanding.
Scott, Rose M.; Roby, Erin
2015-01-01
Prior to age four, children succeed in non-elicited-response false-belief tasks but fail elicited-response false-belief tasks. To explain this discrepancy, the processing-load account argues that the capacity to represent beliefs emerges in infancy, as indicated by early success on non-elicited-response tasks, but that children’s ability to demonstrate this capacity depends on the processing demands of the task and children’s processing skills. When processing demands exceed young children’s processing abilities, such as in standard elicited-response tasks, children fail despite their capacity to represent beliefs. Support for this account comes from recent evidence that reducing processing demands improves young children’s performance: when demands are sufficiently reduced, 2.5-year-olds succeed in elicited-response tasks. Here we sought complementary evidence for the processing-load account by examining whether increasing processing demands impeded children’s performance in a non-elicited-response task. 3-year-olds were tested in a preferential-looking task in which they heard a change-of-location false-belief story accompanied by a picture book; across children, we manipulated the amount of linguistic ambiguity in the story. The final page of the book showed two images: one that was consistent with the main character’s false belief and one that was consistent with reality. When the story was relatively unambiguous, children looked reliably longer at the false-belief-consistent image, successfully demonstrating their false-belief understanding. When the story was ambiguous, however, this undermined children’s performance: looking times to the belief-consistent image were correlated with verbal ability, and only children with verbal skills in the upper quartile of the sample demonstrated a significant preference for the belief-consistent image. These results support the processing-load account by demonstrating that regardless of whether a task involves an elicited response, children’s performance depends on the processing demands of the task and their processing skills. These findings also have implications for alternative, deflationary accounts of early false-belief understanding. PMID:26562840
Carreras-Sureda, Amado; Pihán, Philippe; Hetz, Claudio
2017-01-01
Endoplasmic reticulum (ER) to mitochondria communication has emerged in recent years as a signaling hub regulating cellular physiology with a relevant contribution to diseases including cancer and neurodegeneration. This functional integration is exerted through discrete interorganelle structures known as mitochondria-associated membranes (MAMs). At these domains, ER/mitochondria physically associate to dynamically adjust metabolic demands and the response to stress stimuli. Here, we provide a focused overview of how the ER shapes the function of the mitochondria, giving a special emphasis to the significance of local signaling of the unfolded protein response at MAMs. The implications to cell fate control and the progression of cancer are also discussed.
Response Ant Colony Optimization of End Milling Surface Roughness
Kadirgama, K.; Noor, M. M.; Abd Alla, Ahmed N.
2010-01-01
Metal cutting processes are important due to increased consumer demands for quality metal cutting related products (more precise tolerances and better product surface roughness) that has driven the metal cutting industry to continuously improve quality control of metal cutting processes. This paper presents optimum surface roughness by using milling mould aluminium alloys (AA6061-T6) with Response Ant Colony Optimization (RACO). The approach is based on Response Surface Method (RSM) and Ant Colony Optimization (ACO). The main objectives to find the optimized parameters and the most dominant variables (cutting speed, feedrate, axial depth and radial depth). The first order model indicates that the feedrate is the most significant factor affecting surface roughness. PMID:22294914
[The role of patient flow and surge capacity for in-hospital response in mass casualty events].
Sefrin, Peter; Kuhnigk, Herbert
2008-03-01
Mass casualty events make demands on emergency services and disaster control. However, optimized in- hospital response defines the quality of definitive care. Therefore, German federal law governs the role of hospitals in mass casualty incidents. In hospital casualty surge is depending on resources that have to be expanded with a practicable alarm plan. Thus, in-hospital mass casualty management planning is recommended to be organized by specialized persons. To minimise inhospital patient overflow casualty surge principles have to be implemented in both, pre-hospital and in-hospital disaster planning. World soccer championship 2006 facilitated the initiation of surge and damage control principles in in-hospital disaster planning strategies for German hospitals. The presented concept of strict control of in-hospital patient flow using surge principles minimises the risk of in-hospital breakdown and increases definitive hospital treatment capacity in mass casualty incidents.
Sulfide response analysis for sulfide control using a pS electrode in sulfate reducing bioreactors.
Villa-Gomez, D K; Cassidy, J; Keesman, K J; Sampaio, R; Lens, P N L
2014-03-01
Step changes in the organic loading rate (OLR) through variations in the influent chemical oxygen demand (CODin) concentration or in the hydraulic retention time (HRT) at constant COD/SO4(2-) ratio (0.67) were applied to create sulfide responses for the design of a sulfide control in sulfate reducing bioreactors. The sulfide was measured using a sulfide ion selective electrode (pS) and the values obtained were used to calculate proportional-integral-derivative (PID) controller parameters. The experiments were performed in an inverse fluidized bed bioreactor with automated operation using the LabVIEW software version 2009(®). A rapid response and high sulfide increment was obtained through a stepwise increase in the CODin concentration, while a stepwise decrease to the HRT exhibited a slower response with smaller sulfide increment. Irrespective of the way the OLR was decreased, the pS response showed a time-varying behavior due to sulfide accumulation (HRT change) or utilization of substrate sources that were not accounted for (CODin change). The pS electrode response, however, showed to be informative for applications in sulfate reducing bioreactors. Nevertheless, the recorded pS values need to be corrected for pH variations and high sulfide concentrations (>200 mg/L). Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Aubrey, D. P.; Mims, J. T.; Oswald, S. W.; Teskey, R. O.; Mitchell, R. J.
2016-12-01
Allocation of assimilated carbon to storage provides a critical carbohydrate buffer when metabolic demands exceed current photosynthetic supply; however, our process-level understanding of controls on carbon storage pools and fluxes remains relatively poor. Recent studies have shifted the paradigm from the concept that stored carbon pools are a sink of low priority that accumulate passively when photosynthetic inputs exceed demand toward the concept that these pools are active sinks of high priority. It follows that allocation toward storage—at the expense of growth—is a trait that would be under selective pressure since species that allocate toward storage should be more resilient to disturbance. Using fire-dependent longleaf pine in a series of manipulative and observational studies, we explore how stored carbon dynamics are controlled by a combination of evolutionary, physiological, and ecological pressures. Our manipulative studies revealed large stored carbon pools in roots that maintained belowground metabolism for a year after current photosynthetic supply was restricted. Likewise, the concentration of stored carbon in the smallest, most metabolically active roots was not influenced until nearly one year later. Our observational studies indicated that stored carbon pools differ among closely related species with overlapping natural distributions, but evolutionary histories of different disturbance frequencies and thus, different selective pressures on carbon storage. Our comparisons of stored carbon pools between longleaf trees growing under xeric or mesic soil moisture regimes indicated that allocation toward storage exhibits plasticity through space and time in response to both short- and long-term variations in resource availability. We expect a continuum of responses to disturbances related to ecological niche and evolutionary adaptation that influence the availability of carbohydrates for metabolic demands. We also expect a continuum in stored carbon pools and metabolic buffering capacity among species as well as spatially, temporally, and developmentally within individual species.
Strauss, Gregory P; Lee, Bern G; Waltz, James A; Robinson, Benjamin M; Brown, Jaime K; Gold, James M
2012-11-01
Prior research provides evidence for aberrant cognition-emotion interactions in schizophrenia. In the current study, we aimed to extend these findings by administering the "distractor devaluation" task to 40 individuals with schizophrenia and 32 demographically matched healthy controls. The task consisted of a simple visual search task for neutral faces, followed by an evaluative response made for one of the search items (or a novel item) to determine whether prior attentional selection results in a devaluation of a previously unattended stimulus. We also manipulated working memory demands by preceding the search array with a memory array that required subjects to hold 0, 1, or 2 items in working memory while performing the search array and devaluation task, to determine whether the normative process by which attentional states influence evaluative response is limited by working memory capacity. Results indicated that individuals with schizophrenia demonstrated the typical distractor devaluation effect at working memory load 0, suggesting intact evaluative response. However, the devaluation effect was absent at working memory loads of 1 and 2, suggesting that normal evaluative responses can be abolished in people with schizophrenia when working memory capacity is exceeded. Thus, findings provide further evidence for normal evaluative response in schizophrenia, but clarify that these normal experiences may not hold when working memory demands are too high. Copyright © 2012 Elsevier B.V. All rights reserved.
Strauss, Gregory P.; Lee, Bern G.; Waltz, James A.; Robinson, Benjamin M.; Brown, Jaime K.; Gold, James M.
2012-01-01
Prior research provides evidence for aberrant cognition-emotion interactions in schizophrenia. In the current study, we aimed to extend these findings by administering the “distractor devaluation” task to 40 individuals with schizophrenia and 32 demographically matched healthy controls. The task consisted of a simple visual search task for neutral faces, followed by an evaluative response made for one of the search items (or a novel item) to determine whether prior attentional selection results in a devaluation of a previously unattended stimulus. We also manipulated working memory demands by preceding the search array with a memory array that required subjects to hold 0, 1, or 2 items in working memory while performing the search array and devaluation task, to determine whether the normative process by which attentional states influence evaluative response is limited by working memory capacity. Results indicated that individuals with schizophrenia demonstrated the typical distractor devaluation effect at working memory load 0, suggesting intact evaluative response. However, the devaluation effect was absent at working memory loads of 1 and 2, suggesting that normal evaluative responses can be abolished in people with schizophrenia when working memory capacity is exceeded. Thus, findings provide further evidence for normal evaluative response in schizophrenia, but clarify that these normal experiences may not hold when working memory demands are too high. PMID:22968207
Nakamura, Hideaki; Kobayashi, Shun; Hirata, Yu; Suzuki, Kyota; Mogi, Yotaro; Karube, Isao
2007-10-15
A method to determine the spectrophotometric biochemical oxygen demand (BOD(sp)) was studied with high sensitivity and reproducibility by employing 2,6-dichlorophenolindophenol (DCIP) as a redox color indicator, the yeast Saccharomyces cerevisiae, and a temperature-controlling system providing a three-consecutive-stir unit. The absorbance of DCIP decreased due to the metabolism of organic substances in aqueous samples by S. cerevisiae. Under optimum conditions, a calibration curve for glucose glutamic acid concentration between 1.1 and 22mg O(2) L(-1) (r=0.988, six points, n=3) was obtained when the incubation mixture was incubated for 10min at 30 degrees C. The reproducibility of the optical responses in the calibration curve was 1.77% (average of relative standard deviations; RSD(av)). Subsequently, the characterization of this method was studied. The optical responses to pure organic substances and the influence of chloride ions, artificial seawater, and heavy metal ions on the sensor response were investigated before use with real samples. Measurements of real samples using river water were performed and compared with those obtained using the BOD(5) method. Finally, stable responses were obtained for 36 days when the yeast cell suspension was stored at 4 degrees C (response reduction, 89%; RSD(av) value for 9 testing days, 8.4%).
A Handbook For Acquiring Demand-Responsive Transit Software, Tcrp Report 18
DOT National Transportation Integrated Search
1996-01-01
THIS HANDBOOK WILL BE OF INTEREST TO AGENCIES ENGAGED IN MANAGING AND OPERATING DEMAND-RESPONSIVE TRANSIT (DRT) SERVICES. THE HANDBOOK IS INTENDED TO ASSIST DRTPROVIDERS WITH ASSESSMENT OF SOFTWARE NEEDS AND PROCUREMENT OF SOFTWARE TO MEET THOSE NEED...
Modeling Demand-Responsive Feeder Systems in the UTPS Framework
DOT National Transportation Integrated Search
1978-07-01
For the transit planner considering alternative future transit designs, there has been little in the way of analytical tools available to assess the impact of demand-responsive transportation (DRT) systems. The intent of this report is to provide the...
Evaluating the use of transfers for improving demand responsive systems adopting zoning strategies.
DOT National Transportation Integrated Search
2011-08-01
Due to widely dispersed population density over large and sparsely suburban/rural areas, : conventional fixed route transit services hardly satisfy the travel needs of their residents. As an : alternative, demand responsive transit (DRT) systems have...
Auto-DR and Pre-cooling of Buildings at Tri-City Corporate Center
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yin, Rongxin; Xu, Peng; Kiliccote, Sila
2008-11-01
Over the several past years, Lawrence Berkeley National Laboratory (LBNL) has conducted field tests for different pre-cooling strategies in different commercial buildings within California. The test results indicated that pre-cooling strategies were effective in reducing electric demand in these buildings during peak periods. This project studied how to optimize pre-cooling strategies for eleven buildings in the Tri-City Corporate Center, San Bernardino, California with the assistance of a building energy simulation tool -- the Demand Response Quick Assessment Tool (DRQAT) developed by LBNL's Demand Response Research Center funded by the California Energy Commission's Public Interest Energy Research (PIER) Program. From themore » simulation results of these eleven buildings, optimal pre-cooling and temperature reset strategies were developed. The study shows that after refining and calibrating initial models with measured data, the accuracy of the models can be greatly improved and the models can be used to predict load reductions for automated demand response (Auto-DR) events. This study summarizes the optimization experience of the procedure to develop and calibrate building models in DRQAT. In order to confirm the actual effect of demand response strategies, the simulation results were compared to the field test data. The results indicated that the optimal demand response strategies worked well for all buildings in the Tri-City Corporate Center. This study also compares DRQAT with other building energy simulation tools (eQUEST and BEST). The comparison indicate that eQUEST and BEST underestimate the actual demand shed of the pre-cooling strategies due to a flaw in DOE2's simulation engine for treating wall thermal mass. DRQAT is a more accurate tool in predicting thermal mass effects of DR events.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thompson, Lisa; Lekov, Alex; McKane, Aimee
2010-08-20
This case study enhances the understanding of open automated demand response opportunities in municipal wastewater treatment facilities. The report summarizes the findings of a 100 day submetering project at the San Luis Rey Wastewater Treatment Plant, a municipal wastewater treatment facility in Oceanside, California. The report reveals that key energy-intensive equipment such as pumps and centrifuges can be targeted for large load reductions. Demand response tests on the effluent pumps resulted a 300 kW load reduction and tests on centrifuges resulted in a 40 kW load reduction. Although tests on the facility?s blowers resulted in peak period load reductions ofmore » 78 kW sharp, short-lived increases in the turbidity of the wastewater effluent were experienced within 24 hours of the test. The results of these tests, which were conducted on blowers without variable speed drive capability, would not be acceptable and warrant further study. This study finds that wastewater treatment facilities have significant open automated demand response potential. However, limiting factors to implementing demand response are the reaction of effluent turbidity to reduced aeration load, along with the cogeneration capabilities of municipal facilities, including existing power purchase agreements and utility receptiveness to purchasing electricity from cogeneration facilities.« less
Role of estrogen receptor-α on food demand elasticity.
Minervini, Vanessa; Rowland, Neil E; Robertson, Kimberly L; Foster, Thomas C
2015-05-01
Estrogens have been shown to have an inhibitory effect on food intake under free-feeding conditions, yet the effects of estrogens on food-maintained operant responding have been studied to a much lesser extent and, thus, are not well understood. Therefore, the purpose of the present experiment was to use a behavioral economics paradigm to assess differences in demand elasticity between mice with knockout of the estrogen receptor subtype α, knockout of subtype β, and their wild type controls. The mice responded in a closed economy, and the price of food was increased by increasing the fixed-ratio response requirement every four sessions. Overall, we found that mice with the knockout of receptor subtype α had the most elastic demand functions. Therefore, under these conditions, estrogens increased food seeking via activation of the receptor subtype α. The results were inconsistent with those reported by previous studies that employed free-feeding conditions. © Society for the Experimental Analysis of Behavior.
Price elasticity matrix of demand in power system considering demand response programs
NASA Astrophysics Data System (ADS)
Qu, Xinyao; Hui, Hongxun; Yang, Shengchun; Li, Yaping; Ding, Yi
2018-02-01
The increasing renewable energy power generations have brought more intermittency and volatility to the electric power system. Demand-side resources can improve the consumption of renewable energy by demand response (DR), which becomes one of the important means to improve the reliability of power system. In price-based DR, the sensitivity analysis of customer’s power demand to the changing electricity prices is pivotal for setting reasonable prices and forecasting loads of power system. This paper studies the price elasticity matrix of demand (PEMD). An improved PEMD model is proposed based on elasticity effect weight, which can unify the rigid loads and flexible loads. Moreover, the structure of PEMD, which is decided by price policies and load types, and the calculation method of PEMD are also proposed. Several cases are studied to prove the effectiveness of this method.
Dobryakova, Ekaterina; Rocca, Maria Assunta; Valsasina, Paola; Ghezzi, Angelo; Colombo, Bruno; Martinelli, Vittorio; Comi, Giancarlo; DeLuca, John; Filippi, Massimo
2016-06-01
The Stroop interference task is a cognitively demanding task of executive control, a cognitive ability that is often impaired in patients with multiple sclerosis (MS). The aim of this study was to compare effective connectivity patterns within a network of brain regions involved in the Stroop task performance between MS patients with three disease clinical phenotypes [relapsing-remitting (RRMS), benign (BMS), and secondary progressive (SPMS)] and healthy subjects. Effective connectivity analysis was performed on Stroop task data using a novel method based on causal Bayes networks. Compared with controls, MS phenotypes were slower at performing the task and had reduced performance accuracy during incongruent trials that required increased cognitive control. MS phenotypes also exhibited connectivity abnormalities reflected as weaker shared connections, presence of extra connections (i.e., connections absent in the HC connectivity pattern), connection reversal, and loss. In SPMS and the BMS groups but not in the RRMS group, extra connections were associated with deficits in the Stroop task performance. In the BMS group, the response time associated with correct responses during the congruent condition showed a positive correlation with the left posterior parietal → dorsal anterior cingulate connection. In the SPMS group, performance accuracy during the congruent condition showed a negative correlation with the right insula → left insula connection. No associations between extra connections and behavioral performance measures were observed in the RRMS group. These results suggest that, depending on the phenotype, patients with MS use different strategies when cognitive control demands are high and rely on different network connections. Hum Brain Mapp, 37:2293-2304, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
The value of demand response in Florida
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stoll, Brady; Buechler, Elizabeth; Hale, Elaine
Many electrical loads may be operated flexibly to provide grid services, including peaking capacity, reserves, and load shifting. The authors model 14 demand end uses in Florida and analyze their operational impacts and overall value for a wide range of solar penetrations and grid flexibility options. They find demand response is able to reduce production costs, reduce the number of low-load hours for traditional generators, reduce starting of gas generators, and reduce curtailment.
The value of demand response in Florida
Stoll, Brady; Buechler, Elizabeth; Hale, Elaine
2017-11-10
Many electrical loads may be operated flexibly to provide grid services, including peaking capacity, reserves, and load shifting. The authors model 14 demand end uses in Florida and analyze their operational impacts and overall value for a wide range of solar penetrations and grid flexibility options. They find demand response is able to reduce production costs, reduce the number of low-load hours for traditional generators, reduce starting of gas generators, and reduce curtailment.
Saijo, Yasuaki; Chiba, Shigeru; Yoshioka, Eiji; Nakagi, Yoshihiko; Ito, Toshihiro; Kitaoka-Higashiguchi, Kazuyo; Yoshida, Takahiko
2015-02-01
To elucidate whether low job control and low social support at work have synergistic interaction on mental health. The synergistic interaction was also analyzed after stratification by high and low job demands. Participants were 2,121 local government employees in Asahikawa city, Japan. The Brief Job Stress Questionnaire was used to assess job demands, job control, and social support. Depression was assessed using the Patient Health Questionnaire-9. The Maslach Burnout Inventory-General Survey was used to assess burnout. Insomnia was assessed using the Athens Insomnia Scale. Possible confounder-adjusted logistic regression analyses were performed to obtain odds ratios for depression, burnout, and insomnia, and synergy indices between job control and social support at work were assessed. The synergy indices among men and women, respectively, were 2.08 (80 % confidence interval: 1.01, 4.27) and 1.98 (0.67, 5.89) for depression, 1.79 (1.28, 2.51) and 2.62 (1.07, 6.40) for burnout, and 1.92 (1.22, 3.02) and 2.77 (0.43, 18.01) for insomnia. Men with high job demands had higher synergistic interaction on depression and burnout, compared to men with low job demands, and women with low job demands had higher synergistic interaction between job control and social support at work on burnout and insomnia, compared to women with high job demands. There were more-than-additive interactions of job control and social support at work on depression, burnout, and insomnia. After stratification by job demands, the synergistic interaction may be different between men and women. To assess job stress, it is necessary to consider the interactive effect of not only job demands and job control but also job control and social support at work.
Johnsen, Tone Langjordet; Eriksen, Hege Randi; Indahl, Aage; Tveito, Torill Helene
2017-01-01
Aims: Social support is associated with well-being and positive health outcomes. However, positive outcomes of social support might be more dependent on the way support is provided than the amount of support received. A distinction can be made between directive social support, where the provider resumes responsibility, and nondirective social support, where the receiver has the control. This study examined the relationship between directive and nondirective social support, and subjective health complaints, job satisfaction and perception of job demands and job control. Methods: A survey was conducted among 957 Norwegian employees, working in 114 private kindergartens (mean age 40.7 years, SD = 10.5, 92.8% female), as part of a randomized controlled trial. This study used only baseline data. A factor analysis of the Norwegian version of the Social Support Inventory was conducted, identifying two factors: nondirective and directive social support. Hierarchical regression analyses were then performed. Results: Nondirective social support was related to fewer musculoskeletal and pseudoneurological complaints, higher job satisfaction, and the perception of lower job demands and higher job control. Directive social support had the opposite relationship, but was not statistically significant for pseudoneurological complaints. Conclusions: It appears that for social support to be positively related with job characteristics and subjective health complaints, it has to be nondirective. Directive social support was not only without any association, but had a significant negative relationship with several of the variables. Nondirective social support may be an important factor to consider when aiming to improve the psychosocial work environment. Trial registration: Clinicaltrials.gov: NCT02396797. Registered 23 March 2015. PMID:28820017
Johnsen, Tone Langjordet; Eriksen, Hege Randi; Indahl, Aage; Tveito, Torill Helene
2018-05-01
Social support is associated with well-being and positive health outcomes. However, positive outcomes of social support might be more dependent on the way support is provided than the amount of support received. A distinction can be made between directive social support, where the provider resumes responsibility, and nondirective social support, where the receiver has the control. This study examined the relationship between directive and nondirective social support, and subjective health complaints, job satisfaction and perception of job demands and job control. A survey was conducted among 957 Norwegian employees, working in 114 private kindergartens (mean age 40.7 years, SD = 10.5, 92.8% female), as part of a randomized controlled trial. This study used only baseline data. A factor analysis of the Norwegian version of the Social Support Inventory was conducted, identifying two factors: nondirective and directive social support. Hierarchical regression analyses were then performed. Nondirective social support was related to fewer musculoskeletal and pseudoneurological complaints, higher job satisfaction, and the perception of lower job demands and higher job control. Directive social support had the opposite relationship, but was not statistically significant for pseudoneurological complaints. It appears that for social support to be positively related with job characteristics and subjective health complaints, it has to be nondirective. Directive social support was not only without any association, but had a significant negative relationship with several of the variables. Nondirective social support may be an important factor to consider when aiming to improve the psychosocial work environment. Clinicaltrials.gov: NCT02396797. Registered 23 March 2015.
Laaksonen, Mikko; Rahkonen, Ossi; Martikainen, Pekka; Lahelma, Eero
2006-03-01
To examine associations of job demands and job control, procedural and relational organizational fairness, and physical work load with self-rated general health and mental health. In addition, the effect of occupational class on these associations is examined. The data were derived from the Helsinki Health Study baseline surveys in 2001-2002. Respondents to cross-sectional postal surveys were middle-aged employees of the City of Helsinki (n=5.829, response rate 67%). Associations of job demands and job control, organizational fairness and physical work load with less than good self-rated health and poor GHQ-12 mental health were examined. Those with the poorest working conditions two to three times more, often reported poor general and mental health than those with the best working conditions. Adjustment for occupational class weakened the associations of low job control and physical work load with general health by one fifth, but even more strengthened that of high job demands. Adjustment for occupational class clearly strengthened the associations of job control and physical work load with mental health in men. Mutual adjustment for all working conditions notably weakened their associations with both health measures, except those of job control in men. All working conditions except relational organizational fairness remained independently associated with general and mental health. All studied working conditions were strongly associated with both general and mental health but the associations weakened after mutual adjustments. Of the two organizational fairness measures, procedural fairness remained independently associated with both health outcomes. Adjustment for occupational class had essentially different effects on the associations of different working conditions and different health outcomes.
Sanne, Bjarte; Mykletun, Arnstein; Dahl, Alv A; Moen, Bente E; Tell, Grethe S
2005-09-01
To test the strain/iso-strain, interaction and buffer hypotheses of the Job Demand-Control-Support model in relation to anxiety and depression. Five thousand five hundred and sixty-two workers with valid Demand-Control-Support Questionnaire (DCSQ) scores were examined with the sub-scales of the Hospital Anxiety and Depression Scale as outcomes. Multiple statistical methods were applied. The strain and iso-strain hypotheses were confirmed. Generally, additive and non-interaction effects were found between psychological demands, control and social support. The buffer hypotheses were refuted. Results from analyses testing different interaction operationalizations were complementary. High demands, low control and low support individually, but particularly combined, are risk factors for anxiety and depression. Support is the DCSQ index most strongly associated with anxiety and depression in women. Assessment of psychosocial work environment may identify workers at risk, and serve as a basis for job-redesign.
Impact of job characteristics on psychological health of Chinese single working women.
Yeung, D Y; Tang, C S
2001-01-01
This study aims at investigating the impact of individual and contextual job characteristics of control, psychological and physical demand, and security on psychological distress of 193 Chinese single working women in Hong Kong. The mediating role of job satisfaction in the job characteristics-distress relation is also assessed. Multiple regression analysis results show that job satisfaction mediates the effects of job control and security in predicting psychological distress; whereas psychological job demand has an independent effect on mental distress after considering the effect of job satisfaction. This main effect model indicates that psychological distress is best predicted by small company size, high psychological job demand, and low job satisfaction. Results from a separate regression analysis fails to support the overall combined effect of job demand-control on psychological distress. However, a significant physical job demand-control interaction effect on mental distress is noted, which reduces slightly after controlling the effect of job satisfaction.
Lang, Angelica E.; Stobart, Jamie; Kociolek, Aaron M.; Milosavljevic, Stephan; Trask, Catherine
2017-01-01
Many occupations in agriculture, construction, transportation, and forestry are non-routine, involving non-cyclical tasks, both discretionary and non-discretionary work breaks, and a mix of work activities. Workers in these industries are exposed to seated whole body vibration (WBV) and tasks consisting of physical, mental, or a combination of demands. Risk assessment tools for non-routinized jobs have emerged but there remains a need to understand the combined effects of different work demands to improve risk assessment methods and ultimately inform ergonomists and workers on optimum work arrangement and scheduling strategies. The objective of this study was to investigate fatigue-related human responses of WBV sequentially combined with physical, mental, or concurrent physical and mental demands. Sixteen healthy participants performed four conditions on four separate days: (1) physically demanding work, (2) mentally demanding work, (3) concurrent work, and (4) control quiet sitting. For each condition, participants performed two 15-minute bouts of the experimental task, separated by 30-minutes of simulated WBV based on realistic all-terrain vehicle (ATV) riding data. A test battery of fatigue measures consisting of biomechanical, physiological, cognitive, and sensorimotor measurements were collected at four interval periods: pre-session, after the first bout of the experimental task and before WBV, after WBV and before the second bout of the experimental task, and post-session. Nine measures demonstrated statistically significant time effects during the control condition; 11, 7, and 12 measures were significant in the physical, mental, and concurrent conditions, respectively. Overall, the effects of seated WBV in combination with different tasks are not additive but possibly synergistic or antagonistic. There appears to be a beneficial effect of seated ATV operation as a means of increasing task variation; but since excessive WBV may independently pose a health risk in the longer-term, these beneficial results may not be sensible as a long-term solution. PMID:29236752
Yung, Marcus; Lang, Angelica E; Stobart, Jamie; Kociolek, Aaron M; Milosavljevic, Stephan; Trask, Catherine
2017-01-01
Many occupations in agriculture, construction, transportation, and forestry are non-routine, involving non-cyclical tasks, both discretionary and non-discretionary work breaks, and a mix of work activities. Workers in these industries are exposed to seated whole body vibration (WBV) and tasks consisting of physical, mental, or a combination of demands. Risk assessment tools for non-routinized jobs have emerged but there remains a need to understand the combined effects of different work demands to improve risk assessment methods and ultimately inform ergonomists and workers on optimum work arrangement and scheduling strategies. The objective of this study was to investigate fatigue-related human responses of WBV sequentially combined with physical, mental, or concurrent physical and mental demands. Sixteen healthy participants performed four conditions on four separate days: (1) physically demanding work, (2) mentally demanding work, (3) concurrent work, and (4) control quiet sitting. For each condition, participants performed two 15-minute bouts of the experimental task, separated by 30-minutes of simulated WBV based on realistic all-terrain vehicle (ATV) riding data. A test battery of fatigue measures consisting of biomechanical, physiological, cognitive, and sensorimotor measurements were collected at four interval periods: pre-session, after the first bout of the experimental task and before WBV, after WBV and before the second bout of the experimental task, and post-session. Nine measures demonstrated statistically significant time effects during the control condition; 11, 7, and 12 measures were significant in the physical, mental, and concurrent conditions, respectively. Overall, the effects of seated WBV in combination with different tasks are not additive but possibly synergistic or antagonistic. There appears to be a beneficial effect of seated ATV operation as a means of increasing task variation; but since excessive WBV may independently pose a health risk in the longer-term, these beneficial results may not be sensible as a long-term solution.
Bioinspired Mechano‐Sensitive Macroporous Ceramic Sponge for Logical Drug and Cell Delivery
Xu, Changlu; Wei, Zhihao; Gao, Huajian; Bai, Yanjie; Liu, Huiling; Yang, Huilin
2017-01-01
On‐demand, ultrahigh precision delivery of molecules and cells assisted by scaffold is a pivotal theme in the field of controlled release, but it remains extremely challenging for ceramic‐based macroporous scaffolds that are prevalently used in regenerative medicine. Sea sponges (Phylum Porifera), whose bodies possess hierarchical pores or channels and organic/inorganic composite structures, can delicately control water intake/circulation and therefore achieve high precision mass transportation of food, oxygen, and wastes. Inspired by leuconoid sponge, in this study, the authors design and fabricate a biomimetic macroporous ceramic composite sponge (CCS) for high precision logic delivery of molecules and cells regulated by mechanical stimulus. The CCS reveals unique on‐demand AND logic release behaviors in response to dual‐gates of moisture and pressure (or strain) and, more importantly, 1 cm3 volume of CCS achieves unprecedentedly delivery precision of ≈100 ng per cycle for hydrophobic or hydrophilic molecules and ≈1400 cells per cycle for fibroblasts, respectively. PMID:28638781
Job strain, blood pressure and response to uncontrollable stress.
Steptoe, A; Cropley, M; Joekes, K
1999-02-01
The association between cardiovascular disease risk and job strain (high-demand, low-control work) may be mediated by heightened physiological stress responsivity. We hypothesized that high levels of job strain lead to increased cardiovascular responses to uncontrollable but not controllable stressors. Associations between job strain and blood pressure reductions after the working day (unwinding) were also assessed. Assessment of cardiovascular responses to standardized behavioral tasks, and ambulatory monitoring of blood pressure and heart rate during a working day and evening. We studied 162 school teachers (60 men, 102 women) selected from a larger survey as experiencing high or low job strain. Blood pressure, heart rate and electrodermal responses to an externally paced (uncontrollable) task and a self-paced (controllable) task were assessed. Blood pressure was monitored using ambulatory apparatus from 0900 to 2230 h on a working day. The groups of subjects with high and low job strain did not differ in demographic factors, body mass or resting cardiovascular activity. Blood pressure reactions to the uncontrollable task were greater in high than low job-strain groups, but responses to the controllable task were not significantly different between groups. Systolic and diastolic blood pressure did not differ between groups over the working day, but decreased to a greater extent in the evening in subjects with low job strain. Job strain is associated with a heightened blood pressure response to uncontrollable but not controllable tasks. The failure of subjects with high job strain to show reduced blood pressure in the evening may be a manifestation of chronic allostatic load.
Evidence that convergence rather than accommodation controls intermittent distance exotropia.
Horwood, Anna M; Riddell, Patricia M
2012-03-01
This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Nineteen distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2 m and 33 cm. Stimulus and response AC/A and CA/C ratios were calculated. Accommodation responses for near targets (p = 0.017) and response gains (p = 0.026) were greater in the exotropes than in the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p = 0.02), but significantly higher CA/C ratios (p = 0.02). All the exotropes, whether the angle changed most with lenses ('controlled by accommodation') or on occlusion ('controlled by fusion'), used binocular disparity not blur as their main cue to target distance. Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting overaccommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.
Evidence that convergence rather than accommodation controls intermittent distance exotropia
Horwood, Anna M; Riddell, Patricia M
2015-01-01
Purpose This study considered whether vergence drives accommodation or accommodation drives vergence during the control of distance exotropia for near fixation. High accommodative convergence to accommodation (AC/A) ratios are often used to explain this control, but the role of convergence to drive accommodation (the CA/C relationship) is rarely considered. Atypical CA/C characteristics could equally, or better, explain common clinical findings. Methods 19 distance exotropes, aged 4-11 years, were compared while controlling their deviation with 27 non-exotropic controls aged 5-9 years. Simultaneous vergence and accommodation responses were measured to a range of targets incorporating different combinations of blur, disparity and looming cues at four fixation distances between 2m and 33cm. Stimulus and response AC/A and CA/C ratios were calculated. Results Accommodation responses for near targets (p=0.017) response gains (p=0.026) were greater in the exotropes than the controls. Despite higher clinical stimulus AC/A ratios, the distance exotropes showed lower laboratory response AC/A ratios (p=0.02), but significantly higher CA/C ratios (p=0.02). All the exotropes, whether the angle changed most with lenses (“controlled by accommodation”) or on occlusion (“controlled by fusion”), used binocular disparity not blur as their main cue to target distance. Conclusions Increased vergence demand to control intermittent distance exotropia for near also drives significantly more accommodation. Minus lens therapy is more likely to act by correcting over-accommodation driven by controlling convergence, rather than by inducing blur-driven vergence. The use of convergence as a major drive to accommodation explains many clinical characteristics of distance exotropia, including apparently high near stimulus AC/A ratios. PMID:22280437
Haworth, Matthew; Elliott-Kingston, Caroline; McElwain, Jennifer C
2013-01-01
Plant stomata display a wide range of short-term behavioural and long-term morphological responses to atmospheric carbon dioxide concentration ([CO(2)]). The diversity of responses suggests that plants may have different strategies for controlling gas exchange, yet it is not known whether these strategies are co-ordinated in some way. Here, we test the hypothesis that there is co-ordination of physiological (via aperture change) and morphological (via stomatal density change) control of gas exchange by plants. We examined the response of stomatal conductance (G(s)) to instantaneous changes in external [CO(2)] (C(a)) in an evolutionary cross-section of vascular plants grown in atmospheres of elevated [CO(2)] (1,500 ppm) and sub-ambient [O(2)] (13.0 %) compared to control conditions (380 ppm CO(2), 20.9 % O(2)). We found that active control of stomatal aperture to [CO(2)] above current ambient levels was not restricted to angiosperms, occurring in the gymnosperms Lepidozamia peroffskyana and Nageia nagi. The angiosperm species analysed appeared to possess a greater respiratory demand for stomatal movement than gymnosperm species displaying active stomatal control. Those species with little or no control of stomatal aperture (termed passive) to C(a) were more likely to exhibit a reduction in stomatal density than species with active stomatal control when grown in atmospheres of elevated [CO(2)]. The relationship between the degree of stomatal aperture control to C(a) above ambient and the extent of any reduction in stomatal density may suggest the co-ordination of physiological and morphological responses of stomata to [CO(2)] in the optimisation of water use efficiency. This trade-off between stomatal control strategies may have developed due to selective pressures exerted by the costs associated with passive and active stomatal control.
Ljoså, Cathrine Haugene; Tyssen, Reidar; Lau, Bjørn
2011-11-01
This study aimed to investigate the association between individual and psychosocial work factors and mental distress among offshore shift workers in the Norwegian petroleum industry. All 2406 employees of a large Norwegian oil and gas company, who worked offshore during a two-week period in August 2006, were invited to participate in the web-based survey. Completed questionnaires were received from 1336 employees (56% response rate). The outcome variable was mental distress, assessed with a shortened version of the Hopkins Symptom Checklist (HSCL-5). The following individual factors were adjusted for: age, gender, marital status, and shift work locus of control. Psychosocial work factors included: night work, demands, control and support, and shift work-home interference. The level of mental distress was higher among men than women. In the adjusted regression model, the following were associated with mental distress: (i) high scores on quantitative demands, (ii) low level of support, and (iii) high level of shift work-home interference. Psychosocial work factors explained 76% of the total explained variance (adjusted R (²)=0.21) in the final adjusted model. Psychosocial work factors, such as quantitative demands, support, and shift work-home interference were independently associated with mental distress. Shift schedules were only univariately associated with mental distress.
Knani, Mouna; Fournier, Pierre-Sébastien; Biron, Caroline
2018-05-01
Despite a rich literature on association between psychosocial factors, the demand-control-support (DCS) model and burnout, there are few integrated frameworks encompassing the DCS model, burnout and intention to quit, particularly in a technological context. This manuscript examines the relationships between psychosocial risks, the demand-control-support (DCS) model, burnout syndrome and intention to quit following the introduction of new software at work. Data was collected from agents and advisors working at a Canadian university and using newstudy management software. An online questionnaire was sent via the university's internal mail. Finally, 112 people completed the online survey for a response rate of 60.9% . The results of structural equation modeling show that psychological demands, decision latitude and social support are associated with burnout. It is also clear that burnout, in particular depersonalization and emotional exhaustion, is positively associated with intention to quit. The few studies that raise the negative consequences of technology on quality of life in the workplace, and particularly on health, have not succeeded in establishing a direct link between a deterioration of health and the use of technology. This is due to the fact that there are few epidemiological studies on the direct consequences of the use of ITC on health.
Saunders, Blair; Milyavskaya, Marina; Inzlicht, Michael
2015-09-01
Cognitive control is accompanied by observable negative affect. But how is this negative affect experienced subjectively, and are these feelings related to variation in cognitive control? To address these questions, 42 participants performed a punished inhibitory control task while periodically reporting their subjective experience. We found that within-subject variation in subjective experience predicted control implementation, but not neural monitoring (i.e., the error-related negativity, ERN). Specifically, anxiety and frustration predicted increased and decreased response caution, respectively, while hopelessness accompanied reduced inhibitory control, and subjective effort coincided with the increased ability to inhibit prepotent responses. Clarifying the nature of these phenomenological results, the effects of frustration, effort, and hopelessness-but not anxiety-were statistically independent from the punishment manipulation. Conversely, while the ERN was increased by punishment, the lack of association between this component and phenomenology suggests that early monitoring signals might precede the development of control-related subjective experience. Our results indicate that the types of feelings experienced during cognitively demanding tasks are related to different aspects of controlled performance, critically suggesting that the relationship between emotion and cognitive control extends beyond the dimension of valence. © 2015 Society for Psychophysiological Research.
The Effects of Demand-Responsive Parking on Transit Usage and Congestion: Evidence From Sfpark
DOT National Transportation Integrated Search
2017-09-01
Parking is a serious issue in many urban areas, especially those experiencing rapid population growth. To address this problem, some cities have implemented demand-responsive pricing programs, where parking prices vary depending on the occupancy rate...
Poor impulse control predicts inelastic demand for nicotine but not alcohol in rats.
Diergaarde, Leontien; van Mourik, Yvar; Pattij, Tommy; Schoffelmeer, Anton N M; De Vries, Taco J
2012-05-01
Tobacco and alcohol dependence are characterized by continued use despite deleterious health, social and occupational consequences, implying that addicted individuals pay a high price for their use. In behavioral economic terms, such persistent consumption despite increased costs can be conceptualized as inelastic demand. Recent animal studies demonstrated that high-impulsive individuals are more willing to work for nicotine or cocaine infusions than their low-impulsive counterparts, indicating that this trait might be causally related to inelastic drug demand. By employing progressive ratio schedules of reinforcement combined with a behavioral economics approach of analysis, we determined whether trait impulsivity is associated with an insensitivity of nicotine or alcohol consumption to price increments. Rats were trained on a delayed discounting task, measuring impulsive choice. Hereafter, high- and low-impulsive rats were selected and trained to nose poke for intravenous nicotine or oral alcohol. Upon stable self-administration on a continuous reinforcement schedule, the price (i.e. response requirement) was increased. Demand curves, depicting the relationship between price and consumption, were produced using Hursh's exponential demand equation. Similar to human observations, nicotine and alcohol consumption in rats fitted this equation, thereby demonstrating the validity of our model. Moreover, high-impulsive rats displayed inelastic nicotine demand, as their nicotine consumption was less sensitive to price increments as compared with that in low-impulsive rats. Impulsive choice was not related to differences in alcohol demand elasticity. Our model seems well suited for studying nicotine and alcohol demand in rats and, as such, might contribute to our understanding of tobacco and alcohol dependence. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of Addiction.
Vild, Ondřej; Roleček, Jan; Hédl, Radim; Kopecký, Martin; Utinek, Dušan
2013-12-15
A substantial part of European lowland woodlands was managed as coppices or wood pastures for millennia. However, traditional management forms were almost completely abandoned in Central Europe by the middle of the 20th century. Combined with the effects of nitrogen deposition and herbivore pressure, shifts in management resulted in biodiversity loss affecting particularly light-demanding oligotrophic plant species. Experimental thinning was applied in a former oak coppice-with-standards in an attempt to restore vanishing understorey plant communities. Two levels of thinning intensity and zero management as control were used on 90 plots. Ten years after the treatment, significant changes in species composition and diversity were observed in heavily thinned plots, while moderate thinning had mostly insignificant effects. Light-demanding oligotrophic species significantly increased, indicating positive consequences of restoration. However, heavy thinning also brought about the expansion of native ruderal species. Alien species remained unchanged. We conclude that the restoration of coppice-with-standards can be an efficient tool to support vanishing light-demanding woodland species. Combined with biodiversity benefits, the increasing demand for biofuel may contribute to the renaissance of traditional management forms in forestry.
Qi, Xingliang; Liu, Yapeng; Zhang, Jing; Ji, Shuang; Sluiter, Judith K; Zhou, Renlai; Deng, Huihua
2015-11-01
The purpose of this study was to explore whether work strain (i.e., job demands and job control) and subjective need for recovery (NFR) after work are related to measured concentration of cumulative cortisol. Participants were 43 teachers recruited from kindergarten. They self-reported their NFR, job demands and job control over the last month. NFR was measured with the NFR scale. Job demands and control were assessed with the Chinese version of the Job Content Questionnaire. Hair cortisol was used to represent cumulative cortisol excretion. Hair cortisol concentration (HCC) was measured with high-performance liquid chromatography-tandem mass spectrometry. No significant correlations were found between job demands or job control and HCC. NFR was significantly and inversely correlated with HCC (r = -0.41, p = 0.006). The inverse association between NFR and HCC remained significant when age and job demands and job control were controlled for (p = 0.02). The activity of the hypothalamic-pituitary-adrenal axis declines with the accumulation of NFR after working time.
Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids
Pop, Claudia; Cioara, Tudor; Antal, Marcel; Anghel, Ionut; Salomie, Ioan; Bertoncini, Massimo
2018-01-01
In this paper, we investigate the use of decentralized blockchain mechanisms for delivering transparent, secure, reliable, and timely energy flexibility, under the form of adaptation of energy demand profiles of Distributed Energy Prosumers, to all the stakeholders involved in the flexibility markets (Distribution System Operators primarily, retailers, aggregators, etc.). In our approach, a blockchain based distributed ledger stores in a tamper proof manner the energy prosumption information collected from Internet of Things smart metering devices, while self-enforcing smart contracts programmatically define the expected energy flexibility at the level of each prosumer, the associated rewards or penalties, and the rules for balancing the energy demand with the energy production at grid level. Consensus based validation will be used for demand response programs validation and to activate the appropriate financial settlement for the flexibility providers. The approach was validated using a prototype implemented in an Ethereum platform using energy consumption and production traces of several buildings from literature data sets. The results show that our blockchain based distributed demand side management can be used for matching energy demand and production at smart grid level, the demand response signal being followed with high accuracy, while the amount of energy flexibility needed for convergence is reduced. PMID:29315250
Tan, Lavinia; Hackenberg, Timothy D
2015-11-01
Pigeons' demand and preference for specific and generalized tokens was examined in a token economy. Pigeons could produce and exchange different colored tokens for food, for water, or for food or water. Token production was measured across three phases, which examined: (1) across-session price increases (typical demand curve method); (2) within-session price increases (progressive-ratio, PR, schedule); and (3) concurrent pairwise choices between the token types. Exponential demand curves were fitted to the response data and accounted for over 90% total variance. Demand curve parameter values, Pmax , Omax and α showed that demand was ordered in the following way: food tokens, generalized tokens, water tokens, both in Phase 1 and in Phase 3. This suggests that the preferences were predictable on the basis of elasticity and response output from the demand analysis. Pmax and Omax values failed to consistently predict breakpoints and peak response rates in the PR schedules in Phase 2, however, suggesting limits on a unitary conception of reinforcer efficacy. The patterns of generalized token production and exchange in Phase 3 suggest that the generalized tokens served as substitutes for the specific food and water tokens. Taken together, the present findings demonstrate the utility of behavioral economic concepts in the analysis of generalized reinforcement. © Society for the Experimental Analysis of Behavior.
The Influence of Load and Speed on Individuals' Movement Behavior.
Frost, David M; Beach, Tyson A C; Callaghan, Jack P; McGill, Stuart M
2015-09-01
Because individuals' movement patterns have been linked to their risk of future injury, movement evaluations have become a topic of interest. However, if individuals adapt their movement behavior in response to the demands of a task, the utility of evaluations comprising only low-demand activities could have limited application with regard to the prediction of future injury. This investigation examined the impact of load and speed on individuals' movement behavior. Fifty-two firefighters performed 5 low-demand (i.e., light load, low movement speed) whole-body tasks (i.e., lift, squat, lunge, push, and pull). Each task was then modified by increasing the speed, external load, or speed and load. Select measures of motion were used to characterize the performance of each task, and comparisons were made between conditions. The participants adapted their movement behavior in response to the external demands of a task (64 and 70% of all the variables were influenced [p ≤ 0.05] by changing the load and speed, respectively), but in a manner unique to the task and type of demand. The participants exhibited greater spine and frontal plane knee motion in response to an increase in speed when compared with increasing loads. However, there were a large number of movement strategies exhibited by individual firefighters that differed from the group's response. The data obtained here imply that individuals may not be physically prepared to perform safely or effectively when a task's demands are elevated simply because they exhibit the ability to perform a low-demand activity with competence. Therefore, movement screens comprising only low-demand activities may not adequately reflect an individual's capacity, or their risk of injury, and could adversely affect any recommendations that are made for training or job performance.
Portela, Luciana Fernandes; Kröning Luna, Caroline; Rotenberg, Lúcia; Silva-Costa, Aline; Toivanen, Susanna; Araújo, Tania; Griep, Rosane Härter
2015-01-01
Job strain, derived from high psychological demands and low job control, is associated with insomnia, but information on the role of emotional demands and social support in this relationship is scarce. The aims of this study were (i) to test the association between job strain and self-reported insomnia symptoms, (ii) to evaluate the combination of emotional demands and job control regarding insomnia symptoms, and (iii) to analyze the influence of social support in these relationships. This cross-sectional study refers to a sample of nurses (N = 3,013 and N = 3,035 for Job Strain and Emotional demand-control model, resp.) working at public hospitals in Rio de Janeiro, Brazil. Data were collected through a self-report questionnaire. The prevalence of insomnia symptoms was 34.3%. Job strain was associated with increased odds for insomnia symptoms (OR: 2.20); the same result was observed with the combination of emotional demands and low job control (OR: 1.99). In both models, the inclusion of low social support combined with high demands and low job control led to increased odds for insomnia symptoms, compared to groups with high social support from coworkers and supervisors. Besides job strain, the study of emotional demands and social support are promising with regards to insomnia symptoms, particularly among nurses.
Can an Opportunity to Learn at Work Reduce Stress?: A Revisitation of the Job Demand-Control Model
ERIC Educational Resources Information Center
Panari, Chiara; Guglielmi, Dina; Simbula, Silvia; Depolo, Marco
2010-01-01
Purpose: This paper aims to extend the stress-buffering hypothesis of the demand-control model. In addition to the control variable, it seeks to analyse the role of an opportunity for learning and development (L&D) in the workplace as a moderator variable between increased demands and need for recovery. Design/methodology/approach: A…
Wang, Lei; Li, Baoqiang; Xu, Feng; Xu, Zheheng; Wei, Daqing; Feng, Yujie; Wang, Yaming; Jia, Dechang; Zhou, Yu
2017-10-15
Innovative drug delivery technologies based on smart hydrogels for localized on-demand drug delivery had aroused great interest. To acquire smart UV-crosslinkable chitosan hydrogel for NIR-triggered localized on-demanded drug release, a novel UV-crosslinkable and thermo-responsive chitosan was first designed and synthesized by grafting with poly N-isopropylacrylamide, acetylation of methacryloyl groups and embedding with photothermal carbon. The UV-crosslinkable unit (methacryloyl groups) endowed chitosan with gelation via UV irradiation. The thermo-responsive unit (poly N-isopropylacrylamide) endowed chitosan hydrogel with temperature-triggered volume shrinkage and reversible swelling/de-swelling behavior. The chitosan hybrid hydrogel embedded with photothermal carbon exhibited distinct NIR-triggered volume shrinkage (∼42% shrinkage) in response to temperature elevation as induced by NIR laser irradiation. As a demonstration, doxorubicin release rate was accelerated and approximately 40 times higher than that from non-irradiated hydrogels. The UV-crosslinkable and thermal-responsive hybrid hydrogel served as in situ forming hydrogel-based drug depot is developed for NIR-triggered localized on-demand release. Copyright © 2017 Elsevier Ltd. All rights reserved.
Zurrón, Montserrat; Lindín, Mónica; Cespón, Jesús; Cid-Fernández, Susana; Galdo-Álvarez, Santiago; Ramos-Goicoa, Marta; Díaz, Fernando
2018-01-01
We summarize here the findings of several studies in which we analyzed the event-related brain potentials (ERPs) elicited in participants with mild cognitive impairment (MCI) and in healthy controls during performance of executive tasks. The objective of these studies was to investigate the neural functioning associated with executive processes in MCI. With this aim, we recorded the brain electrical activity generated in response to stimuli in three executive control tasks (Stroop, Simon, and Go/NoGo) adapted for use with the ERP technique. We found that the latencies of the ERP components associated with the evaluation and categorization of the stimuli were longer in participants with amnestic MCI than in the paired controls, particularly those with multiple-domain amnestic MCI, and that the allocation of neural resources for attending to the stimuli was weaker in participants with amnestic MCI. The MCI participants also showed deficient functioning of the response selection and preparation processes demanded by each task.
Zurrón, Montserrat; Lindín, Mónica; Cespón, Jesús; Cid-Fernández, Susana; Galdo-Álvarez, Santiago; Ramos-Goicoa, Marta; Díaz, Fernando
2018-01-01
We summarize here the findings of several studies in which we analyzed the event-related brain potentials (ERPs) elicited in participants with mild cognitive impairment (MCI) and in healthy controls during performance of executive tasks. The objective of these studies was to investigate the neural functioning associated with executive processes in MCI. With this aim, we recorded the brain electrical activity generated in response to stimuli in three executive control tasks (Stroop, Simon, and Go/NoGo) adapted for use with the ERP technique. We found that the latencies of the ERP components associated with the evaluation and categorization of the stimuli were longer in participants with amnestic MCI than in the paired controls, particularly those with multiple-domain amnestic MCI, and that the allocation of neural resources for attending to the stimuli was weaker in participants with amnestic MCI. The MCI participants also showed deficient functioning of the response selection and preparation processes demanded by each task.
Design of capacity incentive and energy compensation for demand response programs
NASA Astrophysics Data System (ADS)
Liu, Zhoubin; Cui, Wenqi; Shen, Ran; Hu, Yishuang; Wu, Hui; Ye, Chengjin
2018-02-01
Variability and Uncertainties caused by renewable energy sources have called for large amount of balancing services. Demand side resources (DSRs) can be a good alternative of traditional generating units to provide balancing service. In the areas where the electricity market has not been fully established, e.g., China, DSRs can help balance the power system with incentive-based demand response programs. However, there is a lack of information about the interruption cost of consumers in these areas, making it hard to determine the rational amount of capacity incentive and energy compensation for the participants of demand response programs. This paper proposes an algorithm to calculate the amount of capacity incentive and energy compensation for demand response programs when there lacks the information about interruption cost. Available statistical information of interruption cost in referenced areas is selected as the referenced data. Interruption cost of the targeted area is converted from the referenced area by product per electricity consumption. On this basis, capacity incentive and energy compensation are obtained to minimize the payment to consumers. Moreover, the loss of consumers is guaranteed to be covered by the revenue they earned from load serving entities.
NASA Astrophysics Data System (ADS)
Anthony, Abigail Walker
This research focuses on the relative advantages and disadvantages of using price-based and quantity-based controls for electricity markets. It also presents a detailed analysis of one specific approach to quantity based controls: the SmartAC program implemented in Stockton, California. Finally, the research forecasts electricity demand under various climate scenarios, and estimates potential cost savings that could result from a direct quantity control program over the next 50 years in each scenario. The traditional approach to dealing with the problem of peak demand for electricity is to invest in a large stock of excess capital that is rarely used, thereby greatly increasing production costs. Because this approach has proved so expensive, there has been a focus on identifying alternative approaches for dealing with peak demand problems. This research focuses on two approaches: price based approaches, such as real time pricing, and quantity based approaches, whereby the utility directly controls at least some elements of electricity used by consumers. This research suggests that well-designed policies for reducing peak demand might include both price and quantity controls. In theory, sufficiently high peak prices occurring during periods of peak demand and/or low supply can cause the quantity of electricity demanded to decline until demand is in balance with system capacity, potentially reducing the total amount of generation capacity needed to meet demand and helping meet electricity demand at the lowest cost. However, consumers need to be well informed about real-time prices for the pricing strategy to work as well as theory suggests. While this might be an appropriate assumption for large industrial and commercial users who have potentially large economic incentives, there is not yet enough research on whether households will fully understand and respond to real-time prices. Thus, while real-time pricing can be an effective tool for addressing the peak load problems, pricing approaches are not well suited to ensure system reliability. This research shows that direct quantity controls are better suited for avoiding catastrophic failure that results when demand exceeds supply capacity.
Su, Zheng; Meng, Tianguang
2016-09-01
The widespread use of information and communication technology (ICT) has reshaped the public sphere in the digital era, making online forums a new channel for political participation. Using big data analytics of full records of citizen-government interactions from 2008 to early 2014 on a nationwide political forum, we find that authoritarian China is considerably responsive to citizens' demands with a rapid growth of response rate; however, government responsiveness is highly selective, conditioning on actors' social identities and the policy domains of their online demands. Results from logistic and duration models suggest that requests which made by local citizens, expressed collectively, focused on the single task issue, and are closely related to economic growth are more likely to be responded to. These strategies adopted by Chinese provincial leaders reveal the scope and selectivity of authoritarian responsiveness. Copyright © 2016 Elsevier Inc. All rights reserved.
Informal eldercare and work-related strain.
Trukeschitz, Birgit; Schneider, Ulrike; Mühlmann, Richard; Ponocny, Ivo
2013-03-01
In light of an aging workforce, reconciling informal eldercare and paid work becomes increasingly pertinent. This article investigates the association between informal eldercare and work-related strain and tests for both the "competing demands" and "expansion" hypotheses. The sample of 938 Austrian employees consisted of employees caring for older relatives and a control group of employees without eldercare obligations. We ran a Tobit regression model on work-related strain with different measures of informal eldercare as explanatory variables and controls for both personal and workplace characteristics. Accounting for different characteristics of eldercare within one estimation model revealed that informal eldercare was associated with work-related strain in 2 ways, that is, it increased with both care hours and subjective care burden. However, after controlling for these burdensome attributes of eldercare, the carer status as such was found to be negatively associated with work-related strain. In addition and independently of care commitments, work-related factors, such as advanced skills and job motivation, reduced work-related strain. This article lends support to both the "competing demands" and the "expansion" hypotheses. Commitment to eldercare can enhance work-related outcomes but entails work-related problems if care burden and time demands of eldercare are substantial. Thus, workers with eldercare responsibilities cannot be considered less productive from the outset. An individual assessment of their situation, considering the care and work setting, is required. Findings from this study support the design of workplace initiatives to uphold workers' productivity in general and bring specific attention to policies alleviating workers' eldercare burden.
Noblet, Andrew J; Allisey, Amanda F; Nielsen, Ingrid L; Cotton, Stacey; LaMontagne, Anthony D; Page, Kathryn M
Job engagement represents a critical resource for community-based health care agencies to achieve high levels of effectiveness. However, studies examining the organizational sources of job engagement among health care professionals have generally overlooked those workers based in community settings. This study drew on the demand-control model, in addition to stressors that are more specific to community health services (e.g., unrewarding management practices), to identify conditions that are closely associated with the engagement experienced by a community health workforce. Job satisfaction was also included as a way of assessing how the predictors of job engagement differ from those associated with other job attitudes. Health and allied health care professionals (n = 516) from two Australian community health services took part in the current investigation. Responses from the two organizations were pooled and analyzed using linear multiple regression. The analyses revealed that three working conditions were predictive of both job engagement and job satisfaction (i.e., job control, quantitative demands, and unrewarding management practices). There was some evidence of differential effects with cognitive demands being associated with job engagement, but not job satisfaction. The results provide important insights into the working conditions that, if addressed, could play key roles in building a more engaged and satisfied community health workforce. Furthermore, working conditions like job control and management practices are amenable to change and thus represent important areas where community health services could enhance the energetic and motivational resources of their employees.
Grümer, Sebastian; Silbereisen, Rainer K; Heckhausen, Jutta
2013-01-01
This paper investigates the association between perceptions of broader changes in the social-ecological context and individuals' subjective well-being (SWB). Macro-level societal changes such as globalization or demographic change give rise to new demands for individual functioning at work and/or in the family. Such new demands associated with social change are stressful and likely to be related to lower levels of SWB. Being active agents, individuals attempt to deal with social change and its increasing demands to protect their SWB. The present study investigates which kinds of control strategies are most effective in protecting one's SWB. Specifically, we predicted that control strategies of goal engagement will be most effective under conditions of perceived high control, and control strategies of goal disengagement will be most effective under conditions of perceived low control. In a large sample of 2537 German adults, work- and family-related demands associated with social change were found to be negatively linked to SWB. Moreover and in line with the motivational theory of lifespan development, control strategies of goal engagement and disengagement were beneficial for SWB to the extent that they matched the perceived control of the demands associated with social change.
van Lankveld, Jacques J D M; van den Hout, Marcel A; Schouten, Erik G W
2004-08-01
Sexually functional (N=26) and sexually dysfunctional heterosexual men with psychogenic erectile disorder (N=23) viewed two sexually explicit videos. Performance demand was manipulated through verbal instruction that a substantial genital response was to be expected from the videos. Self-focused attention was manipulated by introducing a camera pointed at the participant. Dispositional self-consciousness was assessed by questionnaire. Performance demand was found to independently inhibit the genital response. No main effect of self-focus was found. Self-focus inhibited genital response in men scoring high on general and sexual self-consciousness traits, whereas it enhanced penile tumescence in low self-conscious men. Inhibition effects were found in both volunteers and patients. No interaction effects of performance demand and self-focus were found. Subjective sexual arousal in sexually functional men was highest in the self-focus condition. In sexually dysfunctional men, subjective sexual response proved dependent on locus of attention as well as presentation order.
Laboratory Testing of Demand-Response Enabled Household Appliances
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sparn, B.; Jin, X.; Earle, L.
2013-10-01
With the advent of the Advanced Metering Infrastructure (AMI) systems capable of two-way communications between the utility's grid and the building, there has been significant effort in the Automated Home Energy Management (AHEM) industry to develop capabilities that allow residential building systems to respond to utility demand events by temporarily reducing their electricity usage. Major appliance manufacturers are following suit by developing Home Area Network (HAN)-tied appliance suites that can take signals from the home's 'smart meter,' a.k.a. AMI meter, and adjust their run cycles accordingly. There are numerous strategies that can be employed by household appliances to respond tomore » demand-side management opportunities, and they could result in substantial reductions in electricity bills for the residents depending on the pricing structures used by the utilities to incent these types of responses.The first step to quantifying these end effects is to test these systems and their responses in simulated demand-response (DR) conditions while monitoring energy use and overall system performance.« less
Laboratory Testing of Demand-Response Enabled Household Appliances
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sparn, B.; Jin, X.; Earle, L.
2013-10-01
With the advent of the Advanced Metering Infrastructure (AMI) systems capable of two-way communications between the utility's grid and the building, there has been significant effort in the Automated Home Energy Management (AHEM) industry to develop capabilities that allow residential building systems to respond to utility demand events by temporarily reducing their electricity usage. Major appliance manufacturers are following suit by developing Home Area Network (HAN)-tied appliance suites that can take signals from the home's 'smart meter,' a.k.a. AMI meter, and adjust their run cycles accordingly. There are numerous strategies that can be employed by household appliances to respond tomore » demand-side management opportunities, and they could result in substantial reductions in electricity bills for the residents depending on the pricing structures used by the utilities to incent these types of responses. The first step to quantifying these end effects is to test these systems and their responses in simulated demand-response (DR) conditions while monitoring energy use and overall system performance.« less
Huang, Shucai; Zhang, Zhixue; Dai, Yuanyuan; Zhang, Changcun; Yang, Cheng; Fan, Lidan; Liu, Jun; Hao, Wei; Chen, Hongxian
2018-01-01
Studies utilizing functional magnetic resonance imaging (fMRI) cue-reactivity paradigms have demonstrated that short-term abstinent or current methamphetamine (MA) users have increased brain activity in the ventral striatum, caudate nucleus and medial frontal cortex, when exposed to MA-related visual cues. However, patterns of brain activity following cue-reactivity in subjects with long-term MA abstinence, especially long-term compulsory drug rehabilitation, have not been well studied. To enrich knowledge in this field, functional brain imaging was conducted during a cue-reactivity paradigm task in 28 individuals with MA use disorder following long-term compulsory drug rehabilitation, and 27 healthy control subjects. The results showed that, when compared with controls, individuals with MA use disorder displayed elevated activity in the bilateral medial prefrontal cortex (mPFC) and right lateral posterior cingulate cortex in response to MA-related images. Additionally, the anterior cingulate region of mPFC activation during the MA-related cue-reactivity paradigm was positively correlated with craving alterations and previous frequency of drug use. No significant differences in brain activity in response to pornographic images were found between the two groups. Compared to MA cues, individuals with MA use disorder had increased activation in the occipital lobe when exposed to pornographic cues. In conclusion, the present study indicates that, even after long-term drug rehabilitation, individuals with MA use disorder have unique brain activity when exposed to MA-related cues. Additionally, our results illustrate that the libido brain response might be restored, and that sexual demand might be more robust than drug demand, in individuals with MA use disorder following long-term drug rehabilitation. PMID:29725310
Huang, Shucai; Zhang, Zhixue; Dai, Yuanyuan; Zhang, Changcun; Yang, Cheng; Fan, Lidan; Liu, Jun; Hao, Wei; Chen, Hongxian
2018-01-01
Studies utilizing functional magnetic resonance imaging (fMRI) cue-reactivity paradigms have demonstrated that short-term abstinent or current methamphetamine (MA) users have increased brain activity in the ventral striatum, caudate nucleus and medial frontal cortex, when exposed to MA-related visual cues. However, patterns of brain activity following cue-reactivity in subjects with long-term MA abstinence, especially long-term compulsory drug rehabilitation, have not been well studied. To enrich knowledge in this field, functional brain imaging was conducted during a cue-reactivity paradigm task in 28 individuals with MA use disorder following long-term compulsory drug rehabilitation, and 27 healthy control subjects. The results showed that, when compared with controls, individuals with MA use disorder displayed elevated activity in the bilateral medial prefrontal cortex (mPFC) and right lateral posterior cingulate cortex in response to MA-related images. Additionally, the anterior cingulate region of mPFC activation during the MA-related cue-reactivity paradigm was positively correlated with craving alterations and previous frequency of drug use. No significant differences in brain activity in response to pornographic images were found between the two groups. Compared to MA cues, individuals with MA use disorder had increased activation in the occipital lobe when exposed to pornographic cues. In conclusion, the present study indicates that, even after long-term drug rehabilitation, individuals with MA use disorder have unique brain activity when exposed to MA-related cues. Additionally, our results illustrate that the libido brain response might be restored, and that sexual demand might be more robust than drug demand, in individuals with MA use disorder following long-term drug rehabilitation.
29 CFR 20.4 - Determination of delinquency; notice.
Code of Federal Regulations, 2011 CFR
2011-07-01
... appropriate written demands for payment in terms which inform the debtor of the consequences of failure to... progressively stronger written demands at not more than 30-day intervals will normally be made unless a response to the first or second demand indicates that a further demand would be futile and the debtor's...
Modeling demand for public transit services in rural areas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Attaluri, P.; Seneviratne, P.N.; Javid, M.
1997-05-01
Accurate estimates of demand are critical for planning, designing, and operating public transit systems. Previous research has demonstrated that the expected demand in rural areas is a function of both demographic and transit system variables. Numerous models have been proposed to describe the relationship between the aforementioned variables. However, most of them are site specific and their validity over time and space is not reported or perhaps has not been tested. Moreover, input variables in some cases are extremely difficult to quantify. In this article, the estimation of demand using the generalized linear modeling technique is discussed. Two separate models,more » one for fixed-route and another for demand-responsive services, are presented. These models, calibrated with data from systems in nine different states, are used to demonstrate the appropriateness and validity of generalized linear models compared to the regression models. They explain over 70% of the variation in expected demand for fixed-route services and 60% of the variation in expected demand for demand-responsive services. It was found that the models are spatially transferable and that data for calibration are easily obtainable.« less
Sabbath, Erika; Andel, Ross; Zins, Marie; Goldberg, Marcel; Berr, Claudine
2016-01-01
Background Psychosocial work characteristics may predict cognitive functioning after retirement. However, little research has explored specific cognitive domains associated with psychosocial work environments. Our study tested whether exposure to job demands, job control, and their combination during working life predicted post-retirement performance on eight cognitive tests. Methods We used data from French GAZEL cohort members who had undergone post-retirement cognitive testing (n=2,149). Psychosocial job characteristics were measured on average four years before retirement using Karasek’s Job Content Questionnaire (job demands, job control, demand-control combinations). We tested associations between these exposures and post-retirement performance on tests of executive function, visual-motor speed, psycho-motor speed, verbal memory, and verbal fluency using OLS regression. Results Low job control during working life was negatively associated with executive function, psychomotor speed, phonemic fluency, and semantic fluency after retirement (p’s<.05) even after adjustment for demographics, socioeconomic status, health and social behaviours, and vascular risk factors. Both passive (low-demand, low-control) and high-strain (high-demand, low-control) jobs were associated with lower scores on phonemic and semantic fluency when compared to low-strain (low-demand, high-control) jobs. Conclusions Low job control, in combination with both high and low job demands, is associated with post-retirement deficits in some, but not all, cognitive domains. In addition to work stress, associations between passive work and subsequent cognitive function may implicate lack of cognitive engagement at work as a risk factor for future cognitive difficulties. PMID:27188277
Adaptive controller for regenerative and friction braking system
Davis, R.I.
1990-10-16
A regenerative and friction braking system for a vehicle having one or more road wheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the road wheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the road wheels of the vehicle without skidding or slipping will not be exceeded. 8 figs.
A risk analysis approach applied to field surveillance in utility meters in legal metrology
NASA Astrophysics Data System (ADS)
Rodrigues Filho, B. A.; Nonato, N. S.; Carvalho, A. D.
2018-03-01
Field surveillance represents the level of control in metrological supervision responsible for checking the conformity of measuring instruments in-service. Utility meters represent the majority of measuring instruments produced by notified bodies due to self-verification in Brazil. They play a major role in the economy once electricity, gas and water are the main inputs to industries in their production processes. Then, to optimize the resources allocated to control these devices, the present study applied a risk analysis in order to identify among the 11 manufacturers notified to self-verification, the instruments that demand field surveillance.
Adaptive controller for regenerative and friction braking system
Davis, Roy I.
1990-01-01
A regenerative and friction braking system for a vehicle having one or more roadwheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the roadwheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the roadwheels of the vehicle without skidding or slipping will not be exceeded.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fisk, William J.; Mendell, Mark J.; Davies, Molly
This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.
Vastamäki, Heidi; Vastamäki, Martti; Laimi, Katri; Saltychev, Michail
2017-07-01
Poorly functioning work environments may lead to dissatisfaction for the employees and financial loss for the employers. The Job Content Questionnaire (JCQ) was designed to measure social and psychological characteristics of work environments. To investigate the factor construct of the Finnish 14-item version of JCQ when applied to professional orchestra musicians. In a cross-sectional survey, the questionnaire was sent by mail to 1550 orchestra musicians and students. 630 responses were received. Full data were available for 590 respondents (response rate 38%).The questionnaire also contained questions on demographics, job satisfaction, health status, health behaviors, and intensity of playing music. Confirmatory factor analysis of the 2-factor model of JCQ was conducted. Of the 5 estimates, JCQ items in the "job demand" construct, the "conflicting demands" (question 5) explained most of the total variance in this construct (79%) demonstrating almost perfect correlation of 0.63. In the construct of "job control," "opinions influential" (question 10) demonstrated a perfect correlation index of 0.84 and the items "little decision freedom" (question 14) and "allows own decisions" (question 6) showed substantial correlations of 0.77 and 0.65. The 2-factor model of the Finnish 14-item version of JCQ proposed in this study fitted well into the observed data. The "conflicting demands," "opinions influential," "little decision freedom," and "allows own decisions" items demonstrated the strongest correlations with latent factors suggesting that in a population similar to the studied one, especially these items should be taken into account when observed in the response of a population.
Physiological Parameter Response to Variation of Mental Workload.
Marinescu, Adrian Cornelius; Sharples, Sarah; Ritchie, Alastair Campbell; Sánchez López, Tomas; McDowell, Michael; Morvan, Hervé P
2018-02-01
To examine the relationship between experienced mental workload and physiological response by noninvasive monitoring of physiological parameters. Previous studies have examined how individual physiological measures respond to changes in mental demand and subjective reports of workload. This study explores the response of multiple physiological parameters and quantifies their added value when estimating the level of demand. The study presented was conducted in laboratory conditions and required participants to perform a visual-motor task that imposed varying levels of demand. The data collected consisted of physiological measurements (heart interbeat intervals, breathing rate, pupil diameter, facial thermography), subjective ratings of workload (Instantaneous Self-Assessment Workload Scale [ISA] and NASA-Task Load Index), and the performance. Facial thermography and pupil diameter were demonstrated to be good candidates for noninvasive workload measurements: For seven out of 10 participants, pupil diameter showed a strong correlation ( R values between .61 and .79 at a significance value of .01) with mean ISA normalized values. Facial thermography measures added on average 47.7% to the amount of variability in task performance explained by a regression model. As with the ISA ratings, the relationship between the physiological measures and performance showed strong interparticipant differences, with some individuals demonstrating a much stronger relationship between workload and performance measures than others. The results presented in this paper demonstrate that physiological and pupil diameter can be used for noninvasive real-time measurement of workload. The methods presented in this article, with current technological capabilities, are better suited for workplaces where the person is seated, offering the possibility of being applied to pilots and air traffic controllers.
Tovar, Alison; Choumenkovitch, Silvina F; Hennessy, Erin; Boulos, Rebecca; Must, Aviva; Hughes, Sheryl O; Gute, David M; Vikre, Emily Kuross; Economos, Christina D
2015-12-01
We explored the influence of immigrant mothers feeding style on their children's fruit, vegetable and whole grain intake and how this relationship differed by mother's time in the U.S. Baseline data were collected on mother-child (3-12 yrs) dyads enrolled in Live Well (n = 313), a community-based, participatory, randomized controlled lifestyle intervention (2008-2013). Socio-demographics, years of residence in the U.S., behavioral data, and responses to the Caregiver's Feeding Styles Questionnaire (CFSQ) were obtained from the mother. Measured heights and weights were obtained for both mother and child. Child dietary intake was assessed using the Block Food Screener. Separate multiple linear regression models were run, adjusting for child and mother covariates. Interactions between feeding styles and years in the U.S. (<5 and ≥ 5 years), ethnicity, and child age were tested. Sixty-nine percent of mothers were overweight or obese, 46% of the children were overweight or obese. For mothers in the U.S. for<5 years, having a low demanding/high responsive style was associated with lower child intake of whole grains in adjusted models vs. a high demanding/high responsive style (p < 0.05). This was not seen for mothers in the U.S. for≥5 years. Thus, the influence of feeding style on dietary intake may change with length of time in the U.S. These hypotheses-generating findings call for future research to understand how broader socio-cultural factors influence the feeding dynamic among immigrants. Copyright © 2015 Elsevier Ltd. All rights reserved.
Choumenkovitch, Silvina F.; Hennessy, Erin; Boulos, Rebecca; Must, Aviva; Hughes, Sheryl O.; Gute, David M.; Vikre, Emily Kuross; Economos, Christina D.
2015-01-01
We explored the influence of immigrant mothers feeding style on their children’s fruit, vegetable and whole grain intake and how this relationship differed by mother’s time in the U.S. Baseline data were collected on mother-child (3–12 yrs.) dyads enrolled in Live Well (n=313), a community-based, participatory, randomized controlled lifestyle intervention (2008–2013). Socio-demographics, years of residence in the U.S., behavioral data, and responses to the Caregiver’s Feeding Styles Questionnaire (CFSQ) were obtained from the mother. Measured heights and weights were obtained for both mother and child. Child dietary intake was assessed using the Block Food Screener. Separate multiple linear regression models were run, adjusting for child and mother covariates. Interactions between feeding styles and years in the U.S. (<5 and ≥5 years), ethnicity, and child age were tested. Sixty-nine percent of mothers were overweight or obese, 46% of the children were overweight or obese. For mothers in the U.S. for <5 years, having a low demanding/high responsive style was associated with lower child intake of whole grains in adjusted models vs. a high demanding/high responsive style (p<0.05). This was not seen for mothers in the U.S. for ≥5 years. Thus, the influence of feeding style on dietary intake may change with length of time in the U.S. These hypotheses-generating findings call for future research to understand how broader socio-cultural factors influence the feeding dynamic among immigrants. PMID:26122753
Rummel, Jan; Wesslein, Ann-Katrin; Meiser, Thorsten
2017-05-01
Event-based prospective memory (PM) is the ability to remember to perform an intention in response to an environmental cue. Recent microstructure models postulate four distinguishable stages of successful event-based PM fulfillment. That is, (a) the event must be noticed, (b) the intention must be retrieved, (c) the context must be verified, and (d) the intended action must be coordinated with the demands of any currently ongoing task (e.g., Marsh, Hicks, & Watson, 2002b). Whereas the cognitive processes of Stages 1, 2, and 3 have been studied more or less extensively, little is known about the processes of Stage 4 so far. To fill this gap, the authors manipulated the magnitude of response overlap between the ongoing task and the PM task to isolate Stage-4 processes. Results demonstrate that PM performance improves in the presence versus absence of a response overlap, independent of cue saliency (Experiment 1) and of demands from currently ongoing tasks (Experiment 2). Furthermore, working-memory capacity is associated with PM performance, especially when there is little response overlap (Experiments 2 and 3). Finally, PM performance benefits only from strong response overlap, that is, only when the appropriate ongoing-task and PM response keys were identical (Experiment 4). They conclude that coordinating ongoing-task and PM actions puts cognitive demands on the individual which are distinguishable from the demands imposed by cue-detection and intention-retrieval processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
The Giffen Effect: A Note on Economic Purposes.
ERIC Educational Resources Information Center
Williams, William D.
1990-01-01
Describes the Giffen effect: demand for a commodity increases as price increases. Explains how applying control theory eliminates the paradox that the Giffen effect presents to classic economics supply and demand theory. Notes the differences in how conventional demand theory and control theory treat consumer behavior. (CH)
ERIC Educational Resources Information Center
Taylor, Ronald D.; Lopez, Elizabeth I.; Budescu, Mia; McGill, Rebecca Kang
2012-01-01
Association of socially demanding kin relations, mother's emotional support, behavioral control/monitoring, family organization and psychological control with adolescent's internalizing and externalizing problems were assessed in 200 economically disadvantaged, African American mothers and adolescents. Demanding kin relations and mother's…
75 FR 20901 - Standards for Business Practices and Communication Protocols for Public Utilities
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-22
... markets. This rule ensures that participants in wholesale energy markets where demand response products... those markets and addresses performance evaluation methods appropriate to use for demand response... markets, reducing transaction costs and providing an opportunity for more customers to participate in...
Policy impacts on agricultural irrigation electricity demand in the Columbia Basin
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martin, M.; Cox, L.; Nakamoto, S.
Accurately estimating the price elasticity of demand for irrigation electricity is important to major electricity suppliers such as the Bonneville Power Administration (BPA) of the Pacific Northwest. The BPA has a revenue maximization objective, and the elasticity of demand is central to its rate setting process. Several studies have attempted to estimate demand for irrigation electricity, but none has explicitly included federal agricultural policy and program variables. Tins paper discusses how agricultural programs may influence farmers' irrigation decisions and thus their demand for irrigation electricity. It suggests that existing programs serve to make farmers more responsive to electricity rate increasesmore » than would otherwise be the case. Thus, studies that fail to include them may underestimate the responsiveness of farmers to electricity rate increases.« less
Summary of the effects of engine throttle response on airplane formation-flying qualities
NASA Technical Reports Server (NTRS)
Walsh, Kevin R.
1993-01-01
A flight evaluation was conducted to determine the effect of engine throttle response characteristics on precision formation-flying qualities. A variable electronic throttle control system was developed and flight-tested on a TF-104G airplane with a J79-11B engine at the NASA Dryden Flight Research Facility. This airplane was chosen because of its known, very favorable thrust response characteristics. Ten research flights were flown to evaluate the effects of throttle gain, time delay, and fuel control rate limiting on engine handling qualities during a demanding precision wing formation task. Handling quality effects of lag filters and lead compensation time delays were also evaluated. The Cooper and Harper Pilot Rating Scale was used to assign levels of handling quality. Data from pilot ratings and comments indicate that throttle control system time delays and rate limits cause significant degradations in handling qualities. Threshold values for satisfactory (level 1) and adequate (level 2) handling qualities of these key variables are presented. These results may provide engine manufacturers with guidelines to assure satisfactory handling qualities in future engine designs.
NASA Technical Reports Server (NTRS)
Wolfgang, R.; Natarajan, T.; Day, J.
1987-01-01
A feedback control system, called an auxiliary array switch, was designed to connect or disconnect auxiliary solar panel segments from a spacecraft electrical bus to meet fluctuating demand for power. A simulation of the control system was used to carry out a number of design and analysis tasks that could not economically be performed with a breadboard of the hardware. These tasks included: (1) the diagnosis of a stability problem, (2) identification of parameters to which the performance of the control system was particularly sensitive, (3) verification that the response of the control system to anticipated fluctuations in the electrical load of the spacecraft was satisfactory, and (4) specification of limitations on the frequency and amplitude of the load fluctuations.
Generalized Aggregation and Coordination of Residential Loads in a Smart Community
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hao, He; Somani, Abhishek; Lian, Jianming
2015-11-02
Flexibility from residential loads presents an enormous potential to provide various services to the smart grid. In this paper, we propose a unified hierarchical framework for aggregation and coordination of various residential loads in a smart community, such as Thermostatically Controlled Loads (TCLs), Distributed Energy Storages (DESs), residential Pool Pumps (PPs), and Electric Vehicles (EVs). A central idea of this framework is a virtual battery model, which provides a simple and intuitive tool to aggregate the flexibility of distributed loads. Moreover, a multi-stage Nash-bargainingbased coordination strategy is proposed to coordinate different aggregations of residential loads for demand response. Case studiesmore » are provided to demonstrate the efficacy of our proposed framework and coordination strategy in managing peak power demand in a smart residential community.« less
Manipulation of heart rate variability can modify response to anger-inducing stimuli.
Francis, Heather M; Penglis, Kathryn M; McDonald, Skye
2016-10-01
Research suggests that heart rate variability (HRV) is a physiological indicator of the flexibility of the autonomic nervous system and can provide an objective measure of an individual's ability to appropriately match emotional responses to environmental demands. The present study investigated whether angry response to emotional stimuli was related to HRV, and whether manipulation of HRV using biofeedback could change the anger response in a healthy adult population. Fifty-eight participants received HRV biofeedback (n = 29) or an active control condition (n = 29). HRV measures included standard deviation of normal-to-normal intervals (SDNN), low-frequency (LF) and high-frequency (HF) power, and was recorded across three sessions: baseline, training, and anger induction. The anger induction procedure resulted in increased subjective experience of anger, as well as physiological changes. The biofeedback group had higher HRV than active controls both during the training session (SDNN and LF HRV) and during anger induction (LF HRV). HRV during anger induction was significantly associated with self-reported emotional response for participants receiving biofeedback but not for active controls. Results provide support for HRV as an index of emotion regulation, specifically anger. Further research is needed to determine whether long-term HRV biofeedback can have a lasting effect on managing anger.
Enhancing Price Response Programs through Auto-DR: California's 2007 Implementation Experience
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kiliccote, Sila; Wikler, Greg; Chiu, Albert
2007-12-18
This paper describes automated demand response (Auto-DR) activities, an innovative effort in California to ensure that DR programs produce effective and sustainable impacts. Through the application of automation and communication technologies coupled with well-designed incentives and DR programs such as Critical Peak Pricing (CPP) and Demand Bidding (DBP), Auto-DR is opening up the opportunity for many different types of buildings to effectively participate in DR programs. We present the results of Auto-DR implementation efforts by the three California investor-owned utilities for the Summer of 2007. The presentation emphasizes Pacific Gas and Electric Company's (PG&E) Auto-DR efforts, which represents the largestmore » in the state. PG&E's goal was to recruit, install, test and operate 15 megawatts of Auto-DR system capability. We describe the unique delivery approaches, including optimizing the utility incentive structures designed to foster an Auto-DR service provider community. We also show how PG&E's Critical Peak Pricing (CPP) and Demand Bidding (DBP) options were called and executed under the automation platform. Finally, we show the results of the Auto-DR systems installed and operational during 2007, which surpassed PG&E's Auto-DR goals. Auto-DR is being implemented by a multi-disciplinary team including the California Investor Owned Utilities (IOUs), energy consultants, energy management control system vendors, the Lawrence Berkeley National Laboratory (LBNL), and the California Energy Commission (CEC).« less
Communication enabled – fast acting imbalance reserve (CE-FAIR)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilches-Bernal, Felipe; Concepcion, Ricky; Neely, Jason C.
This letter presents a new frequency control strategy that takes advantage of communications and fast responding resources like PV generation, energy storage, wind generation, and demand response, termed collectively as converter interfaced generators (CIGs). The proposed approach uses an active monitoring of power imbalances to rapidly redispatch CIGs. This approach differs from previously proposed frequency control schemes in that it employs feed-forward control based on a measured power imbalance rather that relying on a frequency measurement. As a result, time-domain simulations of the full Western Electricity Coordinating Council (WECC) system are conducted to demonstrate the effectiveness of the proposed method,more » showing improved performance.« less
van der Gracht, Anouk M F; de Geus, Mark A R; Camps, Marcel G M; Ruckwardt, Tracy J; Sarris, Alexi J C; Bremmers, Jessica; Maurits, Elmer; Pawlak, Joanna B; Posthoorn, Michelle M; Bonger, Kimberly M; Filippov, Dmitri V; Overkleeft, Herman S; Robillard, Marc S; Ossendorp, Ferry; van Kasteren, Sander I
2018-06-15
Activation of a cytotoxic T-cell is a complex multistep process, and tools to study the molecular events and their dynamics that result in T-cell activation in situ and in vivo are scarce. Here, we report the design and use of conditional epitopes for time-controlled T-cell activation in vivo. We show that trans-cyclooctene-protected SIINFEKL (with the lysine amine masked) is unable to elicit the T-cell response characteristic for the free SIINFEKL epitope. Epitope uncaging by means of an inverse-electron demand Diels-Alder (IEDDA) event restored T-cell activation and provided temporal control of T-cell proliferation in vivo.
Communication enabled – fast acting imbalance reserve (CE-FAIR)
Wilches-Bernal, Felipe; Concepcion, Ricky; Neely, Jason C.; ...
2017-06-08
This letter presents a new frequency control strategy that takes advantage of communications and fast responding resources like PV generation, energy storage, wind generation, and demand response, termed collectively as converter interfaced generators (CIGs). The proposed approach uses an active monitoring of power imbalances to rapidly redispatch CIGs. This approach differs from previously proposed frequency control schemes in that it employs feed-forward control based on a measured power imbalance rather that relying on a frequency measurement. As a result, time-domain simulations of the full Western Electricity Coordinating Council (WECC) system are conducted to demonstrate the effectiveness of the proposed method,more » showing improved performance.« less