A longitudinal test of the demand-control model using specific job demands and specific job control.

PubMed

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.

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

Work Demands and Work-to-Family and Family-to-Work Conflict: Direct and Indirect Relationships

ERIC Educational Resources Information Center

Voydanoff, Patricia

2005-01-01

This article uses a demands-and-resources approach to examine relationships between three types of work demands and work-to-family and family-to-work conflict: time-based demands, strain-based demands, and boundary-spanning demands. The analysis is based on data from 2,155 employed adults living with a family member who were interviewed for the…

Estimating spatially specific demand and supply of dental services: a longitudinal comparison in Northern Germany.

PubMed

Schwendicke, Falk; Jäger, Ralf; Hoffmann, Wolfgang; Jordan, Rainer A; van den Berg, Neeltje

2016-09-01

Assessing the spatial distribution of oral morbidity-related demand and the workforce-related supply is relevant for planning dental services. We aimed to establish and validate a model for estimating the spatially specific demand and supply. This model was then applied to compare demand-supply ratios in 2001 and 2011 in the federal state of Mecklenburg-Vorpommern (Northern Germany). The spatial units were zip code areas. Demand per area was estimated by linking population-specific oral morbidities to working times via insurance claim data. Estimated demand was validated against the provided demand in 2001 and 2011. Supply was calculated for both years using cohort data from the dentist register. The ratio of demand and supply was geographically mapped and its distribution between areas assessed using the Gini coefficient. Between 2001 and 2011, a significant decrease of the general population (-7.0 percent), the annual demand (-13.1 percent), and the annual supply (-12.9 percent) was recorded. The estimated demands were nearly (2001: -4 percent) and completely (2011: ±0 percent) congruent with provided demands. The average demand-supply-ratio did not change significantly between 2001 and 2011 (P > 0.05), but was increasingly unequally distributed. In both years, few areas were over-serviced, while many were under-serviced. The established model can be used to estimate spatially specific demand and supply. © 2016 American Association of Public Health Dentistry.

The role of temperature in the variability and extremes of electricity and gas demand in Great Britain

NASA Astrophysics Data System (ADS)

Thornton, H. E.; Hoskins, B. J.; Scaife, A. A.

2016-11-01

The daily relationship of electricity and gas demand with temperature in Great Britain is analysed from 1975 to 2013 and 1996 to 2013 respectively. The annual mean and annual cycle amplitude of electricity demand exhibit low frequency variability. This low frequency variability is thought to be predominantly driven by socio-economic changes rather than temperature variation. Once this variability is removed, both daily electricity and gas demand have a strong anti-correlation with temperature (r elec = -0.90 , r gas = -0.94). However these correlations are inflated by the changing demand-temperature relationship during spring and autumn. Once the annual cycles of temperature and demand are removed, the correlations are {r}{{elec}}=-0.60 and {r}{{gas}}=-0.83. Winter then has the strongest demand-temperature relationship, during which a 1 °C reduction in daily temperature typically gives a ˜1% increase in daily electricity demand and a 3%-4% increase in gas demand. Extreme demand periods are assessed using detrended daily temperature observations from 1772. The 1 in 20 year peak day electricity and gas demand estimates are, respectively, 15% (range 14%-16%) and 46% (range 44%-49%) above their average winter day demand during the last decade. The risk of demand exceeding recent extreme events, such as during the winter of 2009/2010, is also quantified.

A comparison of economic demand and conditioned-cued reinstatement of methamphetamine-seeking or food-seeking in rats.

PubMed

Galuska, Chad M; Banna, Kelly M; Willse, Lena Vaughn; Yahyavi-Firouz-Abadi, Noushin; See, Ronald E

2011-08-01

This study examined whether continued access to methamphetamine or food reinforcement changed economic demand for both. The relationship between demand elasticity and cue-induced reinstatement was also determined. Male Long-Evans rats were lever pressed under increasing fixed-ratio requirements for either food pellets or methamphetamine (20 μg/50 μl infusion). For two groups, demand curves were obtained before and after continued access (12 days, 2-h sessions) to the reinforcer under a fixed-ratio 3 schedule. A third group was given continued access to methamphetamine between determinations of food demand and a fourth group abstained from methamphetamine between determinations. All groups underwent extinction sessions, followed by a cue-induced reinstatement test. Although food demand was less elastic than methamphetamine demand, continued access to methamphetamine shifted the methamphetamine demand curve upward and the food demand curve downward. In some rats, methamphetamine demand also became less elastic. Continued access to food had no effect on food demand. Reinstatement was higher after continued access to methamphetamine relative to food. For methamphetamine, elasticity and reinstatement measures were correlated. Continued access to methamphetamine, but not food, alters demand in ways suggestive of methamphetamine accruing reinforcing strength. Demand elasticity thus provides a useful measure of abuse liability that may predict future relapse to renewed drug-seeking and drug use.

Customer premises services market demand assessment 1980 - 2000. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Gamble, R. B.; Saporta, L.; Heidenrich, G. A.

1983-01-01

Estimates of market demand for domestic civilian telecommunications services for the years 1980 to 2000 are provided. Overall demand, demand or satellite services, demand for satellite delivered Customer Premises Service (CPS), and demand for 30/20 GHz Customer Premises Services are covered. Emphasis is placed on the CPS market and demand is segmented by market, by service, by user class and by geographic region. Prices for competing services are discussed and the distribution of traffic with respect to distance is estimated. A nationwide traffic distribution model for CPS in terms of demand for CPS traffic and earth stations for each of the major SMSAs in the United States are provided.

Burnout and engagement at work as a function of demands and control.

PubMed

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.

Intrinsic motivation and organizational identification among on-demand workers.

PubMed

Rockmann, Kevin W; Ballinger, Gary A

2017-09-01

On-demand firms provide services for clients through a network of on-demand workers ready to complete specific tasks for a set contractual price. Given such on-demand work is defined by payment on short-term contracts with no obligation for continued employment, there is little reason to believe on-demand workers experience more than extrinsic motivation and a transactional relationship with the on-demand firm. However, using self-determination theory, we argue that to the degree that on-demand work fulfills innate psychological needs individual on-demand workers will develop intrinsic motivation, which further leads to organizational identification with the on-demand firm. Across 2 survey-based studies we find support for this path to organizational identification. This adds to the literature on motivation and identification by strengthening the link between individual needs and the individual-organizational relationship. Implications for theory and for the management of on-demand workers are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Perseverative Cognition as an Explanatory Mechanism in the Relation Between Job Demands and Sleep Quality.

PubMed

Van Laethem, Michelle; Beckers, Debby G J; Geurts, Sabine A E; Garefelt, Johanna; Magnusson Hanson, Linda L; Leineweber, Constanze

2018-04-01

The aim of this longitudinal three-wave study was to examine (i) reciprocal associations among job demands, work-related perseverative cognition (PC), and sleep quality; (ii) PC as a mediator in-between job demands and sleep quality; and (iii) continuous high job demands in relation to sleep quality and work-related PC over time. A representative sample of the Swedish working population was approached in 2010, 2012, and 2014, and 2316 respondents were included in this longitudinal full-panel survey study. Structural equation modelling was performed to analyse the temporal relations between job demands, work-related PC, and sleep quality. Additionally, a subsample (N = 1149) consisting of individuals who reported the same level of exposure to job demands during all three waves (i.e. stable high, stable moderate, or stable low job demands) was examined in relation to PC and sleep quality over time. Analyses showed that job demands, PC, and poor sleep quality were positively and reciprocally related. Work-related PC mediated the normal and reversed, direct across-wave relations between job demands and sleep quality. Individuals with continuous high job demands reported significantly lower sleep quality and higher work-related PC, compared to individuals with continuous moderate/low job demands. This study substantiated reciprocal relations between job demands, work-related PC, and sleep quality and supported work-related PC as an underlying mechanism of the reciprocal job demands-sleep relationship. Moreover, this study showed that chronically high job demands are a risk factor for low sleep quality.

Acceleration in the care of older adults: new demands as predictors of employee burnout and engagement.

PubMed

Kubicek, Bettina; Korunka, Christian; Ulferts, Heike

2013-07-01

This paper introduces the concept of acceleration-related demands in the care of older adults. It examines these new demands and their relation to cognitive, emotional, and physical job demands and to employee well-being. Various changes in the healthcare systems of Western societies pose new demands for healthcare professionals' careers and jobs. In particular today's societal changes give rise to acceleration-related demands, which manifest themselves in work intensification and in increasing requirements to handle new technical equipment and to update one's job-related knowledge. It is, therefore, of interest to investigate the effects of these new demands on the well-being of employees. Survey. Between March-June 2010 the survey was conducted among healthcare professionals involved in care of older adults in Austria. A total of 1498 employees provided data on cognitive, emotional, and physical job demands and on acceleration-related demands. The outcome variables were the core dimensions of burnout (emotional exhaustion and depersonalization) and engagement (vigour and dedication). Hierarchical regression analyses show that acceleration-related demands explain additional variance for exhaustion, depersonalization, vigour, and dedication when controlling for cognitive, emotional, and physical demands. Furthermore, acceleration-related demands associated with increasing requirements to update one's knowledge are related to positive outcomes (vigour and dedication). Acceleration-related demands associated with an increasing work pace are related to negative outcomes such as emotional exhaustion. Results illustrate that new demands resulting from social acceleration generate potential challenges for on-the-job learning and potential risks to employees' health and well-being. © 2012 Blackwell Publishing Ltd.

Reading text while driving: understanding drivers' strategic and tactical adaptation to distraction.

PubMed

Liang, Yulan; Horrey, William J; Hoffman, Joshua D

2015-03-01

In this study, we investigated how drivers adapt secondary-task initiation and time-sharing behavior when faced with fluctuating driving demands. Reading text while driving is particularly detrimental; however, in real-world driving, drivers actively decide when to perform the task. In a test track experiment, participants were free to decide when to read messages while driving along a straight road consisting of an area with increased driving demands (demand zone) followed by an area with low demands. A message was made available shortly before the vehicle entered the demand zone. We manipulated the type of driving demands (baseline, narrow lane, pace clock, combined), message format (no message, paragraph, parsed), and the distance from the demand zone when the message was available (near, far). In all conditions, drivers started reading messages (drivers' first glance to the display) before entering or before leaving the demand zone but tended to wait longer when faced with increased driving demands. While reading messages, drivers looked more or less off road, depending on types of driving demands. For task initiation, drivers avoid transitions from low to high demands; however, they are not discouraged when driving demands are already elevated. Drivers adjust time-sharing behavior according to driving demands while performing secondary tasks. Nonetheless, such adjustment may be less effective when total demands are high. This study helps us to understand a driver's role as an active controller in the context of distracted driving and provides insights for developing distraction interventions. © 2014, Human Factors and Ergonomics Society.

Drivers for the Value of Demand Response under Increased Levels of Wind and Solar Power; NREL (National Renewable Energy Laboratory)

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

Attentional demands and daily functioning among community-dwelling elders.

PubMed

Jansen, Debra A

2006-01-01

Everyday life is full of numerous demands for attention that can affect the ability to function. For elders, examples of these attentional demands include negotiating public transportation and driving, sensory losses, and physical discomforts and worries that make it harder to concentrate and complete tasks. The purpose of this study was to examine the relation between attentional demands and the ability to manage daily activities requiring concentration for 54 community-dwelling elders (34 women, 20 men). As theorized, attentional demands correlated (r = -.58) significantly with daily functioning: Elders with more attentional demands perceived themselves as having greater difficulty managing tasks requiring concentration. Attentional demands accounted for a significant proportion of variance in functioning (12%), even after partialling out the effects of depressive symptoms and health. Findings support the theorized relation between attentional demands and daily functioning, as well as nursing interventions aimed at decreasing attentional demands to promote effective functioning for elders.

Solar + Storage Synergies for Managing Commercial-Customer Demand Charges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gagnon, P.; Govindarajan, A.; Bird, L.

Demand charges, which are based on a customer’s maximum demand in kilowatts (kW), are a common element of electricity rate structures for commercial customers. Customer-sited solar photovoltaic (PV) systems can potentially reduce demand charges, but the level of savings is difficult to predict, given variations in demand charge designs, customer loads, and PV generation profiles. Lawrence Berkeley National Laboratory (Berkeley Lab) and the National Renewable Energy Laboratory (NREL) are collaborating on a series of studies to understand how solar PV can impact demand charges. Prior studies in the series examined demand charge reductions from solar on a stand-alone basis formore » residential and commercial customers. Those earlier analyses found that solar, alone, has limited ability to reduce demand charges depending on the specific design of the demand charge and on the shape of the customer’s load profile. This latest analysis estimates demand charge savings from solar in commercial buildings when co-deployed with behind-the-meter storage, highlighting the complementary roles of the two technologies. The analysis is based on simulated loads, solar generation, and storage dispatch across a wide variety of building types, locations, system configurations, and demand charge designs.« less

Demand curves for hypothetical cocaine in cocaine-dependent individuals.

PubMed

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.

Occupation-differential construct validity of the Job Content Questionnaire (JCQ) psychological job demands scale with physical job demands items: a mixed methods research.

PubMed

Choi, Bongkyoo; Kurowski, Alicia; Bond, Meg; Baker, Dean; Clays, Els; De Bacquer, Dirk; Punnett, Laura

2012-01-01

The construct validity of the Job Content Questionnaire (JCQ) psychological demands scale in relationship to physical demands has been inconsistent. This study aims to test quantitatively and qualitatively whether the scale validity differs by occupation. Hierarchical clustering analyses of 10 JCQ psychological and physical demands items were conducted in 61 occupations from two datasets: one of non-faculty workers at a university in the United States (6 occupations with 208 total workers) and the other of a Belgian working population (55 occupations with 13,039 total workers). The psychological and physical demands items overlapped in 13 of 61 occupation-stratified clustering analyses. Most of the overlaps occurred in physically-demanding occupations and involved the two psychological demands items, 'work fast' and 'work hard'. Generally, the scale reliability was low in such occupations. Additionally, interviews with eight university workers revealed that workers interpreted the two psychological demands items differently by the nature of their tasks. The scale validity was occupation-differential. The JCQ psychological job demands scale as a job demand measure has been used worldwide in many studies. This study indicates that the wordings of the 'work fast' and 'work hard' items of the scale need to be reworded enough to differentiate mental and physical job demands as intended, 'psychological.'

Projections of the demand for national forest stumpage by region: 1980-2030.

Treesearch

Richard W. Haynes; Kent P. Connaughton; Darius M. Adams

1981-01-01

The concept of regional demand is described and applied to the demand for National Forest stumpage. Specifically, demand functions for stumpage (price-quantity relationships) are developed by decade for the major National Forest Regions. The' demand functions are consistent with the 1980 timber program prepared under requirements of the Renewable Resources...

7 CFR 993.21b - Trade demand.

Code of Federal Regulations, 2010 CFR

2010-01-01

... domestic markets for human consumption as prunes and prune products. (b) Foreign trade demand. The quantity... 7 Agriculture 8 2010-01-01 2010-01-01 false Trade demand. 993.21b Section 993.21b Agriculture... Order Regulating Handling Definitions § 993.21b Trade demand. (a) Domestic trade demand. The quantity of...

Universities, Public Policy and Economic Development in Latin America: The Cases of Mexico and Venezuela.

ERIC Educational Resources Information Center

Lorey, David E.

1992-01-01

Since establishment of national university systems in Mexico and Venezuela, three principal demands have dominated policy formation: government ideological demand; economic demand for expertise; and political and social demand for upward mobility through education. Tensions between these demands have stemmed from economic inability to sustain…

The role of metacognition in prospective memory: anticipated task demands influence attention allocation strategies.

PubMed

Rummel, Jan; Meiser, Thorsten

2013-09-01

The present study investigates how individuals distribute their attentional resources between a prospective memory task and an ongoing task. Therefore, metacognitive expectations about the attentional demands of the prospective-memory task were manipulated while the factual demands were held constant. In Experiments 1a and 1b, we found attentional costs from a prospective-memory task with low factual demands to be significantly reduced when information about the low to-be-expected demands were provided, while prospective-memory performance remained largely unaffected. In Experiment 2, attentional monitoring in a more demanding prospective-memory task also varied with information about the to-be-expected demands (high vs. low) and again there were no equivalent changes in prospective-memory performance. These findings suggest that attention-allocation strategies of prospective memory rely on metacognitive expectations about prospective-memory task demands. Furthermore, the results suggest that attentional monitoring is only functional for prospective memory to the extent to which anticipated task demands reflect objective task demands. Copyright © 2013 Elsevier Inc. All rights reserved.

Demand-specific work ability, poor health and working conditions in middle-aged full-time employees.

PubMed

Nabe-Nielsen, Kirsten; Thielen, Karsten; Nygaard, Else; Thorsen, Sannie Vester; Diderichsen, Finn

2014-07-01

We investigated the prevalence of reduced demand-specific work ability, its association with age, gender, education, poor health, and working conditions, and the interaction between poor health and working conditions regarding reduced demand-specific work ability. We used cross-sectional questionnaire data from 3381 full-time employees responding to questions about vocational education, job demands and social support (working conditions), musculoskeletal pain (MSP) and major depression (MD) (poor health) and seven questions about difficulty managing different job demands (reduced demand-specific work ability). Reduced demand-specific work ability varied from 9% to 19% among the 46-year old and from 11% to 21% among the 56-year old. Age was associated with two, gender with four, and education with all measures of reduced demand-specific work ability. MSP was associated with four and MD was associated with six measures of reduced demand-specific work ability. We found no interaction between working conditions and poor health regarding reduced demand-specific work ability. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Linking job demands and resources to employee engagement and burnout: a theoretical extension and meta-analytic test.

PubMed

Crawford, Eean R; Lepine, Jeffery A; Rich, Bruce Louis

2010-09-01

We refine and extend the job demands-resources model with theory regarding appraisal of stressors to account for inconsistencies in relationships between demands and engagement, and we test the revised theory using meta-analytic structural modeling. Results indicate support for the refined and updated theory. First, demands and burnout were positively associated, whereas resources and burnout were negatively associated. Second, whereas relationships among resources and engagement were consistently positive, relationships among demands and engagement were highly dependent on the nature of the demand. Demands that employees tend to appraise as hindrances were negatively associated with engagement, and demands that employees tend to appraise as challenges were positively associated with engagement. Implications for future research are discussed. Copyright 2010 APA, all rights reserved

Emotional labor demands and compensating wage differentials.

PubMed

Glomb, Theresa M; Kammeyer-Mueller, John D; Rotundo, Maria

2004-08-01

The concept of emotional labor demands and their effects on workers has received considerable attention in recent years, with most studies concentrating on stress, burnout, satisfaction, or other affective outcomes. This study extends the literature by examining the relationship between emotional labor demands and wages at the occupational level. Theories describing the expected effects of job demands and working conditions on wages are described. Results suggest that higher levels of emotional labor demands are associated with lower wage rates for jobs low in cognitive demands and with higher wage rates for jobs high in cognitive demands. Implications of these findings are discussed. (c) 2004 APA

Demand Curves for Hypothetical Cocaine in Cocaine-Dependent Individuals

PubMed Central

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

Forecasting Hourly Water Demands With Seasonal Autoregressive Models for Real-Time Application

NASA Astrophysics Data System (ADS)

Chen, Jinduan; Boccelli, Dominic L.

2018-02-01

Consumer water demands are not typically measured at temporal or spatial scales adequate to support real-time decision making, and recent approaches for estimating unobserved demands using observed hydraulic measurements are generally not capable of forecasting demands and uncertainty information. While time series modeling has shown promise for representing total system demands, these models have generally not been evaluated at spatial scales appropriate for representative real-time modeling. This study investigates the use of a double-seasonal time series model to capture daily and weekly autocorrelations to both total system demands and regional aggregated demands at a scale that would capture demand variability across a distribution system. Emphasis was placed on the ability to forecast demands and quantify uncertainties with results compared to traditional time series pattern-based demand models as well as nonseasonal and single-seasonal time series models. Additional research included the implementation of an adaptive-parameter estimation scheme to update the time series model when unobserved changes occurred in the system. For two case studies, results showed that (1) for the smaller-scale aggregated water demands, the log-transformed time series model resulted in improved forecasts, (2) the double-seasonal model outperformed other models in terms of forecasting errors, and (3) the adaptive adjustment of parameters during forecasting improved the accuracy of the generated prediction intervals. These results illustrate the capabilities of time series modeling to forecast both water demands and uncertainty estimates at spatial scales commensurate for real-time modeling applications and provide a foundation for developing a real-time integrated demand-hydraulic model.

Cognitive task demands, self-control demands and the mental well-being of office workers.

PubMed

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.

29 CFR 100.610 - Written demand for payment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 2 2010-07-01 2010-07-01 false Written demand for payment. 100.610 Section 100.610 Labor... Procedures § 100.610 Written demand for payment. (a) The NLRB will promptly make written demand upon the debtor for payment of money or the return of specific property. The written demand for payment will be...

11 CFR 9409.5 - Procedures for demand for testimony or production of documents.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 11 Federal Elections 1 2010-01-01 2010-01-01 false Procedures for demand for testimony or... § 9409.5 Procedures for demand for testimony or production of documents. (a) A demand directed to the... New York Avenue, NW., Suite 1100, Washington, DC 20005. Acceptance of a demand shall not constitute an...

15 CFR 15.14 - Demand for testimony or production of documents: Department procedures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... represented by an attorney, to refine or limit a demand so that compliance is less burdensome or obtain... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Demand for testimony or production of....14 Demand for testimony or production of documents: Department procedures. (a) Whenever a demand for...

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...

The Work-Family Interface as a Mediator between Job Demands and Employee Behaviour.

PubMed

Jenkins, Jade S; Heneghan, Camille J; Bailey, Sarah F; Barber, Larissa K

2016-04-01

In this investigation, we draw from the job demands-resource model and conservation of resources theory to examine the relationship between job demands, the work-family interface and worker behaviours. Data collected from an online survey of workers revealed that hindrance demands indirectly increase interpersonal and organizational deviance through work interference with family and family interference with work. Challenge demands indirectly predict interpersonal and organizational deviance through work interference with family. Finally, hindrance demands indirectly decreased individual-directed organizational citizenship behaviours through work-to-family enrichment. Taken together, these results stress the relevance of job demand management and resource drain/acquisition to counterproductive and extra-role behaviours. Copyright © 2014 John Wiley & Sons, Ltd.

The Effects of Community Demands, Resources, and Strategies on the Nature and Consequences of the Work-Family Interface: An Agenda for Future Research

ERIC Educational Resources Information Center

Voydanoff, Patricia

2005-01-01

This article presents a broad conceptual framework that suggests ways in which community demands, resources, and strategies influence relationships between work demands, resources, and family well-being. Within-domain and boundary-spanning community demands and resources are proposed to combine with work demands and resources in relation to…

31 CFR 344.9 - How do I redeem a Demand Deposit security?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 31 Money and Finance: Treasury 2 2014-07-01 2014-07-01 false How do I redeem a Demand Deposit...-STATE AND LOCAL GOVERNMENT SERIES Demand Deposit Securities § 344.9 How do I redeem a Demand Deposit security? (a) When must I notify Fiscal Service to redeem a security? A Demand Deposit security can be...

31 CFR 344.9 - How do I redeem a Demand Deposit security?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false How do I redeem a Demand Deposit...-STATE AND LOCAL GOVERNMENT SERIES Demand Deposit Securities § 344.9 How do I redeem a Demand Deposit security? (a) When must I notify BPD to redeem a security? A Demand Deposit security can be redeemed at the...

31 CFR 344.9 - How do I redeem a Demand Deposit security?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false How do I redeem a Demand Deposit...-STATE AND LOCAL GOVERNMENT SERIES Demand Deposit Securities § 344.9 How do I redeem a Demand Deposit security? (a) When must I notify BPD to redeem a security? A Demand Deposit security can be redeemed at the...

31 CFR 344.9 - How do I redeem a Demand Deposit security?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false How do I redeem a Demand Deposit...-STATE AND LOCAL GOVERNMENT SERIES Demand Deposit Securities § 344.9 How do I redeem a Demand Deposit security? (a) When must I notify BPD to redeem a security? A Demand Deposit security can be redeemed at the...

31 CFR 344.9 - How do I redeem a Demand Deposit security?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false How do I redeem a Demand Deposit...-STATE AND LOCAL GOVERNMENT SERIES Demand Deposit Securities § 344.9 How do I redeem a Demand Deposit security? (a) When must I notify BPD to redeem a security? A Demand Deposit security can be redeemed at the...

The effects of stochastic demand and expense preference behaviour on public hospital costs and excess capacity.

PubMed

Lovell, C A Knox; Rodríguez-Alvarez, Ana; Wall, Alan

2009-02-01

The literature to date on the effect of demand uncertainty on public hospital costs and excess capacity has not taken into account the role of expense preference behaviour. Similarly, the research on expense preference behaviour has not taken demand uncertainty into account. In this paper, we argue that both demand uncertainty and expense preference behaviour may affect public hospital costs and excess capacity and that ignoring either of these effects may lead to biased parameter estimates and misleading inference. To show this, we extend the analysis of Rodríguez-Alvarez and Lovell (Health Econ. 2004; 13: 157-169) by incorporating demand uncertainty into the technology to account for the hospital activity of providing standby capacity or insurance against the unexpected demand. We find that demand uncertainty in Spanish public hospitals affects hospital production decisions and increases costs. Our results also show that overcapitalization in these hospitals can be explained by hospitals providing insurance demand when faced with demand uncertainty. We also find evidence of expense preference behaviour. We conclude that both stochastic demand and expense preference behaviour should be taken into account when analysing hospital costs and production. Copyright (c) 2008 John Wiley & Sons, Ltd.

Maximum spectral demands in the near-fault region

USGS Publications Warehouse

Huang, Yin-Nan; Whittaker, Andrew S.; Luco, Nicolas

2008-01-01

The Next Generation Attenuation (NGA) relationships for shallow crustal earthquakes in the western United States predict a rotated geometric mean of horizontal spectral demand, termed GMRotI50, and not maximum spectral demand. Differences between strike-normal, strike-parallel, geometric-mean, and maximum spectral demands in the near-fault region are investigated using 147 pairs of records selected from the NGA strong motion database. The selected records are for earthquakes with moment magnitude greater than 6.5 and for closest site-to-fault distance less than 15 km. Ratios of maximum spectral demand to NGA-predicted GMRotI50 for each pair of ground motions are presented. The ratio shows a clear dependence on period and the Somerville directivity parameters. Maximum demands can substantially exceed NGA-predicted GMRotI50 demands in the near-fault region, which has significant implications for seismic design, seismic performance assessment, and the next-generation seismic design maps. Strike-normal spectral demands are a significantly unconservative surrogate for maximum spectral demands for closest distance greater than 3 to 5 km. Scale factors that transform NGA-predicted GMRotI50 to a maximum spectral demand in the near-fault region are proposed.

Maximum spectral demands in the near-fault region

USGS Publications Warehouse

Huang, Y.-N.; Whittaker, A.S.; Luco, N.

2008-01-01

The Next Generation Attenuation (NGA) relationships for shallow crustal earthquakes in the western United States predict a rotated geometric mean of horizontal spectral demand, termed GMRotI50, and not maximum spectral demand. Differences between strike-normal, strike-parallel, geometric-mean, and maximum spectral demands in the near-fault region are investigated using 147 pairs of records selected from the NGA strong motion database. The selected records are for earthquakes with moment magnitude greater than 6.5 and for closest site-to-fault distance less than 15 km. Ratios of maximum spectral demand to NGA-predicted GMRotI50 for each pair of ground motions are presented. The ratio shows a clear dependence on period and the Somerville directivity parameters. Maximum demands can substantially exceed NGA-predicted GMRotI50 demands in the near-fault region, which has significant implications for seismic design, seismic performance assessment, and the next-generation seismic design maps. Strike-normal spectral demands are a significantly unconservative surrogate for maximum spectral demands for closest distance greater than 3 to 5 km. Scale factors that transform NGA-predicted GMRotI50 to a maximum spectral demand in the near-fault region are proposed. ?? 2008, Earthquake Engineering Research Institute.

Income distribution trends and future food demand.

PubMed

Cirera, Xavier; Masset, Edoardo

2010-09-27

This paper surveys the theoretical literature on the relationship between income distribution and food demand, and identifies main gaps of current food modelling techniques that affect the accuracy of food demand projections. At the heart of the relationship between income distribution and food demand is Engel's law. Engel's law establishes that as income increases, households' demand for food increases less than proportionally. A consequence of this law is that the particular shape of the distribution of income across individuals and countries affects the rate of growth of food demand. Our review of the literature suggests that existing models of food demand fail to incorporate the required Engel flexibility when (i) aggregating different food budget shares among households; and (ii) changing budget shares as income grows. We perform simple simulations to predict growth in food demand under alternative income distribution scenarios taking into account nonlinearity of food demand. Results suggest that (i) distributional effects are to be expected from changes in between-countries inequality, rather than within-country inequality; and (ii) simulations of an optimistic and a pessimistic scenario of income inequality suggest that world food demand in 2050 would be 2.7 per cent higher and 5.4 per cent lower than distributional-neutral growth, respectively.

Explaining worker strain and learning: how important are emotional job demands?

PubMed

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.

World Motor Vehicle Demand

DOT National Transportation Integrated Search

1982-08-01

This report discusses the level and nature of world motor vehicle demand for the period 1980-1990. A general understanding of the structure of motor vehicle demand is developed. Published demand forecasts, varying widely, are gathered and their discr...

Experts’ perceptions of the concept of induced demand in healthcare: A qualitative study in Isfahan, Iran

PubMed Central

Keyvanara, Mahmoud; Karimi, Saeed; Khorasani, Elahe; Jazi, Marzie Jafarian

2014-01-01

Context: One of the most important subjects in health economics and healthcare management is the theory of induced demand. There are different views about the concept of induced demand. Extensive texts have been presented on induced demand, however a compatible concept has not necessarily been provided for this phenomenon and it has not been defined explicitly. Aims: The main aim of this article is to understand the concept of induced demand with the use of experts’ perceptions of Isfahan University of Medical Sciences. Settings and Design: The research was done using a qualitative method. Semi-structured interview was used for data generation. Participants in this study were people who had been informed in this regard and had to be experienced and were known as experts. Purposive sampling was done for data saturation. Materials and Methods: Seventeen people were interviewed and criteria such as “reliability of information” and “stability” of the data were considered. The anonymity of the interviewees was preserved. Statistical Analysis Used: The data are transcribed, categorized and then the thematic analysis was used. Results: In this study, 21 sub-categories and three main categories were derived. Three main subjects were included: Induced demand definition, induced demand elements, and induced demand methods. Each of these issues contained some sub-subjects. Conclusion: The result of this study provides a framework for examining the concept of induced demand. The most notable findings include the definition of induced demand, induced demand elements, and method of induced demand. In induced demand definition, an important issue that is often overlooked is that inducing regarding to the effectiveness of clinical services and medical values can lead to better or worse outcomes for patients. These findings help the health policy makers study the phenomenon of induced demand with clear-sighted approach. PMID:25013820

Resource Demand Scenarios for the Major Metals.

PubMed

Elshkaki, Ayman; Graedel, T E; Ciacci, Luca; Reck, Barbara K

2018-03-06

The growth in metal use in the past few decades raises concern that supplies may be insufficient to meet demands in the future. From the perspective of historical and current use data for seven major metals-iron, manganese, aluminum, copper, nickel, zinc, and lead-we have generated several scenarios of potential metal demand from 2010 to 2050 under alternative patterns of global development. We have also compared those demands with various assessments of potential supply to midcentury. Five conclusions emerge: (1) The calculated demand for each of the seven metals doubles or triples relative to 2010 levels by midcentury; (2) The largest demand increases relate to a scenario in which increasingly equitable values and institutions prevail throughout the world; (3) The metal recycling flows in the scenarios meet only a modest fraction of future metals demand for the next few decades; (4) In the case of copper, zinc, and perhaps lead, supply may be unlikely to meet demand by about midcentury under the current use patterns of the respective metals; (5) Increased rates of demand for metals imply substantial new energy provisioning, leading to increases in overall global energy demand of 21-37%. These results imply that extensive technological transformations and governmental initiatives could be needed over the next several decades in order that regional and global development and associated metal demand are not to be constrained by limited metal supply.

The impact of predicted demand on energy production

NASA Astrophysics Data System (ADS)

El kafazi, I.; Bannari, R.; Aboutafail, My. O.

2018-05-01

Energy is crucial for human life, a secure and accessible supply of power is essential for the sustainability of societies. Economic development and demographic progression increase energy demand, prompting countries to conduct research and studies on energy demand and production. Although, increasing in energy demand in the future requires a correct determination of the amount of energy supplied. Our article studies the impact of demand on energy production to find the relationship between the two latter and managing properly the production between the different energy sources. Historical data of demand and energy production since 2000 are used. The data are processed by the regression model to study the impact of demand on production. The obtained results indicate that demand has a positive and significant impact on production (high impact). Production is also increasing but at a slower pace. In this work, Morocco is considered as a case study.

Development of S-ARIMA Model for Forecasting Demand in a Beverage Supply Chain

NASA Astrophysics Data System (ADS)

Mircetic, Dejan; Nikolicic, Svetlana; Maslaric, Marinko; Ralevic, Nebojsa; Debelic, Borna

2016-11-01

Demand forecasting is one of the key activities in planning the freight flows in supply chains, and accordingly it is essential for planning and scheduling of logistic activities within observed supply chain. Accurate demand forecasting models directly influence the decrease of logistics costs, since they provide an assessment of customer demand. Customer demand is a key component for planning all logistic processes in supply chain, and therefore determining levels of customer demand is of great interest for supply chain managers. In this paper we deal with exactly this kind of problem, and we develop the seasonal Autoregressive IntegratedMoving Average (SARIMA) model for forecasting demand patterns of a major product of an observed beverage company. The model is easy to understand, flexible to use and appropriate for assisting the expert in decision making process about consumer demand in particular periods.

Demanding Patient or Demanding Encounter?: A Case Study of a Cancer Clinic

PubMed Central

Stacey, Clare Louise; Henderson, Stuart; MacArthur, Kelly R; Dohan, Daniel

2009-01-01

This paper explores the sociological relevance of demanding encounters between doctors and patients. Borrowing from Potter and McKinlay's (2005) reconceptualization of the doctor-patient relationship, we suggest an analytic shift away from `demanding patients' toward `demanding encounters'. Such a shift places provider-patient conflict within a broader sociocultural context, emphasizing constraints facing both doctor and patient as they interact in a clinical setting. Specifically, through an ethnographic study of doctor-patient interactions at the oncology clinic of a US University Hospital, we examine the respective influences of new information technologies and patient consumerism in the production of demanding encounters in oncology. Findings suggest that these interconnected socio-cultural realities, in tandem with patient tendencies to challenge physician judgment or expertise, play a role in demanding encounters. We conclude by considering the implications of demanding encounters for doctors, patients and healthcare organizations. PMID:19619924

Workload and Performance in Air Traffic Control: Exploring the Influence of Levels of Automation and Variation in Task Demand

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.

Improving productivity and profitability of a bioanalytical business through sales and operation planning.

PubMed

Islam, Rafiqul

2013-07-01

Today's bioanalytical CROs face increasing global competition, highly variable demand, high fixed costs, pricing pressure, and increasing demand for quality and speed. Most bioanalytical laboratories have responded to these challenges by implementing automation and by implementing process improvement methodologies (e.g., Six Sigma). These solutions have not resulted in a significant improvement in productivity and profitability since none of them are able to predict the upturn or downturn in demand. High volatility of demand causes long lead times and high costs during peak demand and poor productivity during trough demand. Most bioanalytical laboratories lack the tools to align supply efficiently to meet changing demand. In this paper, sales and operation planning (S&OP) has been investigated as a tool to balance supply and demand. The S&OP process, when executed effectively, can be the single greatest determinant of profitability for a bioanalytical business.

[Study on elasticity of medical service demand at the township level in China].

PubMed

Shi, Hong-xing; Lv, Jun; Xie, Yi-ping; Wang, Ying; Jia, Jin-zhong; Chang, Feng-shui; Duan, Lin; Sun, Mei; Wang, Zhi-feng; Hao, Mo

2010-06-18

To find out the economic laws regulating medical service demand in accordance with influencing factors at the township level, thus to provide references for further adjusting the medical service demand reasonably in the future. The model of medical service demand was established to measure the elasticity of demand in 49 township health clinics in 1995, 1999, 2003 and 2007. The price elasticity of outpatient and inpatient demand was stable during the four periods, and the average value was -0.029 and -0.132 respectively; the average value of income elasticity was 0.973 and 0.977, registering a downward trend in general. The medical service demand at the township level is price inelastic, indicating that it is a necessity for rural residents. The downward trend of income elasticity under the influence of some health policies illustrates a lightening in economic burden for medical service demand among rural residents in township health clinics.

The 30/20 GHz fixed communications systems service demand assessment. Volume 2: Main report

NASA Technical Reports Server (NTRS)

Gamble, R. B.; Seltzer, H. R.; Speter, K. M.; Westheimer, M.

1979-01-01

A forecast of demand for telecommunications services through the year 2000 is presented with particular reference to demand for satellite communications. Estimates of demand are provided for voice, video, and data services and for various subcategories of these services. The results are converted to a common digital measure in terms of terabits per year and aggregated to obtain total demand projections.

Deriving local demand for stumpage from estimates of regional supply and demand.

Treesearch

Kent P. Connaughton; Gerard A. Majerus; David H. Jackson

1989-01-01

The local (Forest-level or local-area) demand for stumpage can be derived from estimates of regional supply and demand. The derivation of local demand is justified when the local timber economy is similar to the regional timber economy; a simple regression of local on nonlocal prices can be used as an empirical test of similarity between local and regional economies....

Identifying the critical physical demanding tasks of paramedic work: Towards the development of a physical employment standard.

PubMed

Fischer, Steven L; Sinden, Kathryn E; MacPhee, Renee S

2017-11-01

Public safety related occupations including police, fire and military commonly apply physical employment standard (PES) to facilitate job matching, an approach to evaluate if candidates demonstrate acceptable physical capabilities as required to perform the job safely and effectively. In Canada, paramedics remain as one of the few public safety occupations without an evidence-based, validated PES. The purpose of this study was to document and describe the physical demands of paramedic work and to identify the most physically demanding tasks. These outcomes are essential to inform the design and development of an evidence-based PES for the paramedic sector. Physical demands of paramedic work were documented and described using a direct observation-based task analysis technique. Five paramedic's were trained to document the physical demands of their work, then applied their training to observe more than 90 calls over the course of 20 full 12-h work shifts. Physical demands data were then listed in a survey, administered service-wide, where 155 frontline paramedics identified critically demanding tasks and rank-ordered physical demands from not physically demanding to very strongly demanding. Critically important and physically demanding tasks were identified such as: transferring a patient; loading or unloading a stretcher in to or out of the ambulance; performing CPR; and, raising and lowering a stretcher. It is important that a paramedic-based PES evaluate a candidate's physical capabilities to perform the critical and physically demanding tasks identified in this study. Copyright © 2017 Elsevier Ltd. All rights reserved.

Alcohol-Approach Inclinations and Drinking Identity as Predictors of Behavioral Economic Demand for Alcohol

PubMed Central

Ramirez, Jason J.; Dennhardt, Ashley A.; Baldwin, Scott A.; Murphy, James G.; Lindgren, Kristen P.

2016-01-01

Behavioral economic demand curve indices of alcohol consumption reflect decisions to consume alcohol at varying costs. Although these indices predict alcohol-related problems beyond established predictors, little is known about the determinants of elevated demand. Two cognitive constructs that may underlie alcohol demand are alcohol-approach inclinations and drinking identity. The aim of this study was to evaluate implicit and explicit measures of these constructs as predictors of alcohol demand curve indices. College student drinkers (N = 223, 59% female) completed implicit and explicit measures of drinking identity and alcohol-approach inclinations at three timepoints separated by three-month intervals, and completed the Alcohol Purchase Task to assess demand at Time 3. Given no change in our alcohol-approach inclinations and drinking identity measures over time, random intercept-only models were used to predict two demand indices: Amplitude, which represents maximum hypothetical alcohol consumption and expenditures, and Persistence, which represents sensitivity to increasing prices. When modeled separately, implicit and explicit measures of drinking identity and alcohol-approach inclinations positively predicted demand indices. When implicit and explicit measures were included in the same model, both measures of drinking identity predicted Amplitude, but only explicit drinking identity predicted Persistence. In contrast, explicit measures of alcohol-approach inclinations, but not implicit measures, predicted both demand indices. Therefore, there was more support for explicit, versus implicit, measures as unique predictors of alcohol demand. Overall, drinking identity and alcohol-approach inclinations both exhibit positive associations with alcohol demand and represent potentially modifiable cognitive constructs that may underlie elevated demand in college student drinkers. PMID:27379444

Residential demand for energy. Volume 1: Residential energy demand in the US

NASA Astrophysics Data System (ADS)

Taylor, L. D.; Blattenberger, G. R.; Rennhack, R. K.

1982-04-01

Updated and improved versions of the residential energy demand models that are currently used in EPRI's Demand 80/81 Model are presented. The primary objective of the study is the development and estimation of econometric demand models that take into account in a theoretically appropriate way the problems caused by decreasing-block pricing in the sale of electricity and natural gas. An ancillary objective is to take into account the impact on electricity, natural gas, and fuel oil demands of differences and changes in the availability of natural gas. Econometric models of residential demand are estimated for all three fuel tyes using time series data by state. Price and income elasticities for a number of alternative models are presented.

The 30/20 GHz fixed communications systems service demand assessment. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Gamble, R. B.; Seltzer, H. R.; Speter, K. M.; Westheimer, M.

1979-01-01

Demand for telecommunications services is forecasted for the period 1980-2000, with particular reference to that portion of the demand associated with satellite communications. Overall demand for telecommunications is predicted to increase by a factor of five over the period studied and the satellite portion of demand will increase even more rapidly. Traffic demand is separately estimated for voice, video, and data services and is also described as a function of distance traveled and city size. The satellite component of projected demand is compared with the capacity available in the C and Ku satellite bands and it is projected that new satellite technology and the implementation of Ka band transmission will be needed in the decade of the 1990's.

Demand-Withdraw Patterns in Marital Conflict in the Home.

PubMed

Papp, Lauren M; Kouros, Chrystyna D; Cummings, E Mark

2009-06-01

The present study extended laboratory-based findings of demand-withdraw communication into marital conflict in the home and further explored its linkages with spousal depression. U.S. couples (N = 116) provided diary reports of marital conflict and rated depressive symptoms. Hierarchical linear modeling results indicated that husband demand-wife withdraw and wife demand-husband withdraw occurred in the home at equal frequency, and both were more likely to occur when discussing topics that concerned the marital relationship. For both patterns, conflict initiator was positively linked to the demander role. Accounting for marital satisfaction, both demand-withdraw patterns predicted negative emotions and tactics during marital interactions and lower levels of conflict resolution. Spousal depression was linked to increased likelihood of husband demand-wife withdraw.

Demand forecast model based on CRM

NASA Astrophysics Data System (ADS)

Cai, Yuancui; Chen, Lichao

2006-11-01

With interiorizing day by day management thought that regarding customer as the centre, forecasting customer demand becomes more and more important. In the demand forecast of customer relationship management, the traditional forecast methods have very great limitation because much uncertainty of the demand, these all require new modeling to meet the demands of development. In this paper, the notion is that forecasting the demand according to characteristics of the potential customer, then modeling by it. The model first depicts customer adopting uniform multiple indexes. Secondly, the model acquires characteristic customers on the basis of data warehouse and the technology of data mining. The last, there get the most similar characteristic customer by their comparing and forecast the demands of new customer by the most similar characteristic customer.

NAS Demand Predictions, Transportation Systems Analysis Model (TSAM) Compared with Other Forecasts

NASA Technical Reports Server (NTRS)

Viken, Jeff; Dollyhigh, Samuel; Smith, Jeremy; Trani, Antonio; Baik, Hojong; Hinze, Nicholas; Ashiabor, Senanu

2006-01-01

The current work incorporates the Transportation Systems Analysis Model (TSAM) to predict the future demand for airline travel. TSAM is a multi-mode, national model that predicts the demand for all long distance travel at a county level based upon population and demographics. The model conducts a mode choice analysis to compute the demand for commercial airline travel based upon the traveler s purpose of the trip, value of time, cost and time of the trip,. The county demand for airline travel is then aggregated (or distributed) to the airport level, and the enplanement demand at commercial airports is modeled. With the growth in flight demand, and utilizing current airline flight schedules, the Fratar algorithm is used to develop future flight schedules in the NAS. The projected flights can then be flown through air transportation simulators to quantify the ability of the NAS to meet future demand. A major strength of the TSAM analysis is that scenario planning can be conducted to quantify capacity requirements at individual airports, based upon different future scenarios. Different demographic scenarios can be analyzed to model the demand sensitivity to them. Also, it is fairly well know, but not well modeled at the airport level, that the demand for travel is highly dependent on the cost of travel, or the fare yield of the airline industry. The FAA projects the fare yield (in constant year dollars) to keep decreasing into the future. The magnitude and/or direction of these projections can be suspect in light of the general lack of airline profits and the large rises in airline fuel cost. Also, changes in travel time and convenience have an influence on the demand for air travel, especially for business travel. Future planners cannot easily conduct sensitivity studies of future demand with the FAA TAF data, nor with the Boeing or Airbus projections. In TSAM many factors can be parameterized and various demand sensitivities can be predicted for future travel. These resulting demand scenarios can be incorporated into future flight schedules, therefore providing a quantifiable demand for flights in the NAS for a range of futures. In addition, new future airline business scenarios are investigated that illustrate when direct flights can replace connecting flights and larger aircraft can be substituted, only when justified by demand.

Utilizing Traveler Demand Modeling to Predict Future Commercial Flight Schedules in the NAS

NASA Technical Reports Server (NTRS)

Viken, Jeff; Dollyhigh, Samuel; Smith, Jeremy; Trani, Antonio; Baik, Hojong; Hinze, Nicholas; Ashiabor, Senanu

2006-01-01

The current work incorporates the Transportation Systems Analysis Model (TSAM) to predict the future demand for airline travel. TSAM is a multi-mode, national model that predicts the demand for all long distance travel at a county level based upon population and demographics. The model conducts a mode choice analysis to compute the demand for commercial airline travel based upon the traveler s purpose of the trip, value of time, cost and time of the trip,. The county demand for airline travel is then aggregated (or distributed) to the airport level, and the enplanement demand at commercial airports is modeled. With the growth in flight demand, and utilizing current airline flight schedules, the Fratar algorithm is used to develop future flight schedules in the NAS. The projected flights can then be flown through air transportation simulators to quantify the ability of the NAS to meet future demand. A major strength of the TSAM analysis is that scenario planning can be conducted to quantify capacity requirements at individual airports, based upon different future scenarios. Different demographic scenarios can be analyzed to model the demand sensitivity to them. Also, it is fairly well know, but not well modeled at the airport level, that the demand for travel is highly dependent on the cost of travel, or the fare yield of the airline industry. The FAA projects the fare yield (in constant year dollars) to keep decreasing into the future. The magnitude and/or direction of these projections can be suspect in light of the general lack of airline profits and the large rises in airline fuel cost. Also, changes in travel time and convenience have an influence on the demand for air travel, especially for business travel. Future planners cannot easily conduct sensitivity studies of future demand with the FAA TAF data, nor with the Boeing or Airbus projections. In TSAM many factors can be parameterized and various demand sensitivities can be predicted for future travel. These resulting demand scenarios can be incorporated into future flight schedules, therefore providing a quantifiable demand for flights in the NAS for a range of futures. In addition, new future airline business scenarios are investigated that illustrate when direct flights can replace connecting flights and larger aircraft can be substituted, only when justified by demand.

Ad libitum or demand/semi-demand feeding versus scheduled interval feeding for preterm infants.

PubMed

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.

The moderating effect of control over work scheduling and overtime on the relationship between workload demands and perceived job risk.

PubMed

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.

Disaggregating residential water demand for improved forecasts and decision making

NASA Astrophysics Data System (ADS)

Woodard, G.; Brookshire, D.; Chermak, J.; Krause, K.; Roach, J.; Stewart, S.; Tidwell, V.

2003-04-01

Residential water demand is the product of population and per capita demand. Estimates of per capita demand often are based on econometric models of demand, usually based on time series data of demand aggregated at the water provider level. Various studies have examined the impact of such factors as water pricing, weather, and income, with many other factors and details of water demand remaining unclear. Impacts of water conservation programs often are estimated using simplistic engineering calculations. Partly as a result of this, policy discussions regarding water demand management often focus on water pricing, water conservation, and growth control. Projecting water demand is often a straight-forward, if fairly uncertain process of forecasting population and per capita demand rates. SAHRA researchers are developing improved forecasts of residential water demand by disaggregating demand to the level of individuals, households, and specific water uses. Research results based on high-resolution water meter loggers, household-level surveys, economic experiments and recent census data suggest that changes in wealth, household composition, and individual behavior may affect demand more than changes in population or the stock of landscape plants, water-using appliances and fixtures, generally considered the primary determinants of demand. Aging populations and lower fertility rates are dramatically reducing household size, thereby increasing the number of households and residences for a given population. Recent prosperity and low interest rates have raised home ownership rates to unprecented levels. These two trends are leading to increased per capita outdoor water demand. Conservation programs have succeeded in certain areas, such as promoting drought-tolerant native landscaping, but have failed in other areas, such as increasing irrigation efficiency or curbing swimming pool water usage. Individual behavior often is more important than the household's stock of water-using fixtures, and ranges from hedonism (installing pools and whirlpool tubs) to satisficing (adjusting irrigation timers only twice per year) to acting on deeply-held conservation ethics in ways that not only fail any benefit-cost test, but are discouraged, or even illegal (reuse of gray water and black water). Research findings are being captured in dynamic simulation models that integrate social and natural science to create tools to assist water resource managers in providing sustainable water supplies and improving residential water demand forecasts. These models feature simple, graphical user interfaces and output screens that provide decision makers with visual, easy-to-understand information at the basin level. The models reveal connections between various supply and demand components, and highlight direct impacts and feedback mechanisms associated with various policy options.

Robust Unit Commitment Considering Uncertain Demand Response

DOE PAGES

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

Task-dependent individual differences in prefrontal connectivity.

PubMed

Biswal, Bharat B; Eldreth, Dana A; Motes, Michael A; Rypma, Bart

2010-09-01

Recent advances in neuroimaging have permitted testing of hypotheses regarding the neural bases of individual differences, but this burgeoning literature has been characterized by inconsistent results. To test the hypothesis that differences in task demands could contribute to between-study variability in brain-behavior relationships, we had participants perform 2 tasks that varied in the extent of cognitive involvement. We examined connectivity between brain regions during a low-demand vigilance task and a higher-demand digit-symbol visual search task using Granger causality analysis (GCA). Our results showed 1) Significant differences in numbers of frontoparietal connections between low- and high-demand tasks 2) that GCA can detect activity changes that correspond with task-demand changes, and 3) faster participants showed more vigilance-related activity than slower participants, but less visual-search activity. These results suggest that relatively low-demand cognitive performance depends on spontaneous bidirectionally fluctuating network activity, whereas high-demand performance depends on a limited, unidirectional network. The nature of brain-behavior relationships may vary depending on the extent of cognitive demand. High-demand network activity may reflect the extent to which individuals require top-down executive guidance of behavior for successful task performance. Low-demand network activity may reflect task- and performance monitoring that minimizes executive requirements for guidance of behavior.

Task-Dependent Individual Differences in Prefrontal Connectivity

PubMed Central

Biswal, Bharat B.; Eldreth, Dana A.; Motes, Michael A.

2010-01-01

Recent advances in neuroimaging have permitted testing of hypotheses regarding the neural bases of individual differences, but this burgeoning literature has been characterized by inconsistent results. To test the hypothesis that differences in task demands could contribute to between-study variability in brain-behavior relationships, we had participants perform 2 tasks that varied in the extent of cognitive involvement. We examined connectivity between brain regions during a low-demand vigilance task and a higher-demand digit–symbol visual search task using Granger causality analysis (GCA). Our results showed 1) Significant differences in numbers of frontoparietal connections between low- and high-demand tasks 2) that GCA can detect activity changes that correspond with task-demand changes, and 3) faster participants showed more vigilance-related activity than slower participants, but less visual-search activity. These results suggest that relatively low-demand cognitive performance depends on spontaneous bidirectionally fluctuating network activity, whereas high-demand performance depends on a limited, unidirectional network. The nature of brain-behavior relationships may vary depending on the extent of cognitive demand. High-demand network activity may reflect the extent to which individuals require top-down executive guidance of behavior for successful task performance. Low-demand network activity may reflect task- and performance monitoring that minimizes executive requirements for guidance of behavior. PMID:20064942

7 CFR 987.11 - Trade demand.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Trade demand. 987.11 Section 987.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... RIVERSIDE COUNTY, CALIFORNIA Order Regulating Handling Definitions § 987.11 Trade demand. Trade demand means...

7 CFR 987.11 - Trade demand.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Trade demand. 987.11 Section 987.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... RIVERSIDE COUNTY, CALIFORNIA Order Regulating Handling Definitions § 987.11 Trade demand. Trade demand means...

7 CFR 987.11 - Trade demand.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Trade demand. 987.11 Section 987.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... RIVERSIDE COUNTY, CALIFORNIA Order Regulating Handling Definitions § 987.11 Trade demand. Trade demand means...

7 CFR 987.11 - Trade demand.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Trade demand. 987.11 Section 987.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... RIVERSIDE COUNTY, CALIFORNIA Order Regulating Handling Definitions § 987.11 Trade demand. Trade demand means...

Effective production planning for purchased part under long lead time and uncertain demand: MRP Vs demand-driven MRP

NASA Astrophysics Data System (ADS)

Shofa, M. J.; Moeis, A. O.; Restiana, N.

2018-04-01

MRP as a production planning system is appropriate for the deterministic environment. Unfortunately, most production systems such as customer demands are stochastic, so that MRP is inappropriate at the time. Demand-Driven MRP (DDMRP) is new approach for production planning system dealing with demand uncertainty. The objective of this paper is to compare the MRP and DDMRP for purchased part under long lead time and uncertain demand in terms of average inventory levels. The evaluation is conducted through a discrete event simulation with the long lead time and uncertain demand scenarios. The next step is evaluating the performance of DDMRP by comparing the inventory level of DDMRP with MRP. As result, DDMRP is more effective production planning than MRP in terms of average inventory levels.

Residential energy demand and the taxation of housing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gentry, W.M.

1994-12-31

This paper examines how the favorable tax treatment of housing capital in the U.S. affects the demand for residential energy. Relative to a tax system that is neutral between different investments, the current taxation of housing lowers the cost of housing capital by 23%. The tax subsidy for housing capital increases the demand for housing services and the concomitant energy demand and creates an incentive for the substitution of capital for energy in the production of housing services. Eliminating this tax subsidy for housing would lower the demand for housing services by 11.8% and residential energy demand by 6.8%. Alternatively,more » the same reduction in residential energy demand could be obtained through a 20% tax on residential energy. 13 refs., 4 tabs.« less

Drivers of U.S. mineral demand

USGS Publications Warehouse

Sznopek, John L.

2006-01-01

Introduction: The word 'demand' has different meanings for different people. To some, it means their 'wants and needs,' to others it is what they consume. Yet, when considering economics, demand refers to the specific amounts of goods or services that individuals will purchase at various prices. Demand is measured over a given time period. It is determined by a number of factors including income, tastes, and the price of complementary and substitute goods. In this paper, the term consumption is used fairly synonymously with the term demand. Most mineral commodities, like iron ore, copper, zinc, and gravel, are intermediate goods, which means that they are used in the production of other goods, called final goods. Demand for intermediate goods is called derived demand because such demand is derived from the demand for final goods. When demand increases for a commodity, generally the price rises. With everything else held constant, this increases the profits for those who provide this commodity. Normally, this would increase profits of existing producers and attract new producers to the market. When demand for a commodity decreases, generally the price falls. Normally, this would cause profits to fall and, as a consequence, the least efficient firms may be forced from the industry. Demand changes for specific materials as final goods or production techniques are reengineered while maintaining or improving product performance, for example, the use of aluminum in the place of copper in long distance electrical transmission lines or plastic replacing steel in automobile bumpers. Substitution contributes to efficient material usage by utilizing cheaper or technically superior materials. In this way, it may also alleviate materials scarcity. If a material becomes relatively scarce (and thus more expensive), a more abundant (and less expensive) material generally replaces it (Wagner and others, 2003, p. 91).

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

Research determines intelligent consumption of forest products is growing and saving trees - an example with wooden pallets

Treesearch

Philip A. Araman; Robert J. Bush; Bruce Hansen

2001-01-01

Wooden pallets help transport, store and sell products demanded by all of us. As our population and product demands increase, so do the demands for wooden pallets. We will present data on the industrial demands for wooden pallets. We will explain how increased demands for wood pallets in the US have required less new wood from trees and show that the pallet industry is...

A generic method for projecting and valuing domestic water uses, application to the Mediterranean basin at the 2050 horizon.

NASA Astrophysics Data System (ADS)

Neverre, Noémie; Dumas, Patrice

2014-05-01

The aim is to be able to assess future domestic water demands in a region with heterogeneous levels of economic development. This work offers an original combination of a quantitative projection of demands (similar to WaterGAP methodology) and an estimation of the marginal benefit of water. This method is applicable to different levels of economic development and usable for large-scale hydroeconomic modelling. The global method consists in building demand functions taking into account the impact of both the price of water and the level of equipment, proxied by economic development, on domestic water demand. Our basis is a 3-blocks inverse demand function: the first block consists of essential water requirements for food and hygiene; the second block matches intermediate needs; and the last block corresponds to additional water consumption, such as outdoor uses, which are the least valued. The volume of the first block is fixed to match recommended basic water requirements from the literature, but we assume that the volume limits of blocks 2 and 3 depend on the level of household equipment and therefore evolve with the level of GDP per capita (structural change), with a saturation. For blocks 1 and 2 we determine the value of water from elasticity, price and quantity data from the literature, using the point-extension method. For block 3, we use a hypothetical zero-cost demand and maximal demand with actual water costs to linearly interpolate the inverse demand function. These functions are calibrated on the 24 countries part of the Mediterranean basin using data from SIMEDD, and are used for the projection and valuation of domestic water demands at the 2050 horizon. They enable to project total water demand, and also the respective shares of the different categories of demand (basic demand, intermediate demand and additional uses). These projections are performed under different combined scenarios of population, GDP and water costs.

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...

Capturing well-being in activity pattern models within activity-based travel demand models.

DOT National Transportation Integrated Search

2013-03-01

The activity-based approach which is based on the premise that the demand for travel is derived : from the demand for activities, currently constitutes the state of the art in metropolitan travel : demand forecasting and particularly in a form known ...

Capturing well-being in activity pattern models within activity-based travel demand models.

DOT National Transportation Integrated Search

2013-04-01

The activity-based approach which is based on the premise that the demand for travel is derived : from the demand for activities, currently constitutes the state of the art in metropolitan travel : demand forecasting and particularly in a form known ...

Clinical-outcome-based demand management in health services.

PubMed

Brogan, C; Lawrence, D; Mayhew, L

2008-01-01

THE PROBLEM OF MANAGING DEMAND: Most healthcare systems have 'third-party payers' who face the problem of keeping within budgets despite pressures to increase resources due to the ageing population, new technologies and patient demands to lower thresholds for care. This paper uses the UK National Health Service as a case study to suggest techniques for system-based demand management, which aims to control demand and costs whilst maintaining the cost-effectiveness of the system. The technique for managing demand in primary, elective and urgent care consists of managing treatment thresholds for appropriate care, using a whole-systems approach and costing the care elements in the system. It is important to analyse activity in relation to capacity and demand. Examples of using these techniques in practice are given. The practical effects of using such techniques need evaluation. If these techniques are not used, managing demand and limiting healthcare expenditure will be at the expense of clinical outcomes and unmet need, which will perpetuate financial crises.

A model and solving algorithm of combination planning for weapon equipment based on Epoch-era analysis method

NASA Astrophysics Data System (ADS)

Wang, Meng; Zhang, Huaiqiang; Zhang, Kan

2017-10-01

Focused on the circumstance that the equipment using demand in the short term and the development demand in the long term should be made overall plans and took into consideration in the weapons portfolio planning and the practical problem of the fuzziness in the definition of equipment capacity demand. The expression of demand is assumed to be an interval number or a discrete number. With the analysis method of epoch-era, a long planning cycle is broke into several short planning cycles with different demand value. The multi-stage stochastic programming model is built aimed at maximize long-term planning cycle demand under the constraint of budget, equipment development time and short planning cycle demand. The scenario tree is used to discretize the interval value of the demand, and genetic algorithm is designed to solve the problem. At last, a case is studied to demonstrate the feasibility and effectiveness of the proposed mode.

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.

The relationship between wind power, electricity demand and winter weather patterns in Great Britain

NASA Astrophysics Data System (ADS)

Thornton, Hazel E.; Scaife, Adam A.; Hoskins, Brian J.; Brayshaw, David J.

2017-06-01

Wind power generation in Great Britain has increased markedly in recent years. However due to its intermittency its ability to provide power during periods of high electricity demand has been questioned. Here we characterise the winter relationship between electricity demand and the availability of wind power. Although a wide range of wind power capacity factors is seen for a given demand, the average capacity factor reduces by a third between low and high demand. However, during the highest demand average wind power increases again, due to strengthening easterly winds. The nature of the weather patterns affecting Great Britain are responsible for this relationship. High demand is driven by a range of high pressure weather types, each giving cold conditions, but variable wind power availability. Offshore wind power is sustained at higher levels and offers a more secure supply compared to that onshore. However, during high demand periods in Great Britain neighbouring countries may struggle to provide additional capacity due to concurrent low temperatures and low wind power availability.

Physical demand of seven closed agility drills.

PubMed

Atkinson, Mark; Rosalie, Simon; Netto, Kevin

2016-11-01

The present study aimed to quantify the demand of seven generic, closed agility drills. Twenty males with experience in invasion sports volunteered to participate in this study. They performed seven, closed agility drills over a standardised 30-m distance. Physical demand measures of peak velocity, total foot contacts, peak impacts, completion time, and maximum heart rate were obtained via the use of wearable sensor technologies. A subjective rating of perceived exertion (RPE) was also obtained. All measures, with the exception of maximum heart rates and RPE were able to delineate drills in terms of physical and physiological demand. The findings of this study exemplify the differences in demand of agility-type movements. Drill demand was dictated by the type of agility movement initiated with the increase in repetitiveness of a given movement type also contributing to increased demand. Findings from this study suggest agility drills can be manipulated to vary physical and physiological demand. This allows for the optimal application of training principles such as overload, progression, and periodisation.

The composition of demand for newly launched vaccines: results from the pneumococcal and rotavirus vaccine introductions in Ethiopia and Malawi

PubMed Central

Kidane, Teklay; Chirwa, Geoffrey; Tesfaye, Neghist; Prescott, Marta R; Scotney, Soleine T; Valle, Moussa; Abebe, Sintayehu; Tambuli, Adija; Malewezi, Bridget; Mohammed, Tahir; Kobayashi, Emily; Wootton, Emily; Wong, Renee; Dosani, Rahima; Subramaniam, Hamsa; Joseph, Jessica; Yavuz, Elif; Apple, Aliza; Le Tallec, Yann; Kang’ethe, Alice

2016-01-01

Understanding post-launch demand for new vaccines can help countries maximize the benefits of immunization programmes. In particular, low- and middle-income countries (LMICs) should ensure adequate resource planning with regards to stock consumption and service delivery for new vaccines, whereas global suppliers must produce enough vaccines to meet demand. If a country underestimates the number of children seeking vaccination, a stock-out of commodities will create missed opportunities for saving lives. We describe the post-launch demand for the first dose of pneumococcal conjugate vaccine (PCV1) in Ethiopia and Malawi and the first dose of rotavirus vaccine (Rota1) in Malawi, with focus on the new birth cohort and the ‘backlog cohort’, comprised of older children who are still eligible for vaccination at the time of launch. PCV1 and Rota1 uptake were compared with the demand for the first dose of pentavalent vaccine (Penta1), a routine immunization that targets the same age group and immunization schedule. In the first year, the total demand for PCV1 was 37% greater than that of Penta1 in Ethiopia and 59% greater in Malawi. In the first 6 months, the demand of Rota1 was only 5.9% greater than Penta1 demand in Malawi. Over the first three post-introduction months, 70.7% of PCV1 demand in Ethiopia and 71.5% of demand in Malawi came from children in the backlog cohort, whereas only 28.0% of Rota1 demand in Malawi was from the backlog cohort. The composition of demand was impacted by time elapsed since vaccine introduction and age restrictions. Evidence suggests that countries’ plans should account for the impact of backlog demand, especially in the first 3 months post-introduction. LMICs should request for higher stock volumes when compared with routine needs, plan social mobilization activities to reach the backlog cohort and allocate human resources and cold chain capacity to accommodate high demand following vaccine introduction. PMID:26856361

Sediment oxygen demand in the Saddle River and Salem River watersheds, New Jersey, July-August 2008

USGS Publications Warehouse

Heckathorn, Heather A.; Gibs, Jacob

2010-01-01

Many factors, such as river depth and velocity, biochemical oxygen demand, and algal productivity, as well as sediment oxygen demand, can affect the concentration of dissolved oxygen in the water column. Measurements of sediment oxygen demand, in conjunction with those of other water-column water-quality constituents, are useful for quantifying the mechanisms that affect in-stream dissolved-oxygen concentrations. Sediment-oxygen-demand rates are also needed to develop and calibrate a water-quality model being developed for the Saddle River and Salem River Basins in New Jersey to predict dissolved-oxygen concentrations. This report documents the methods used to measure sediment oxygen demand in the Saddle River and Salem River watersheds along with the rates of sediment oxygen demand that were obtained during this investigation. In July and August 2008, sediment oxygen demand was measured in situ in the Saddle River and Salem River watersheds. In the Saddle River Basin, sediment oxygen demand was measured twice at two sites and once at a third location; in the Salem River Basin, sediment oxygen demand was measured three times at two sites and once at a third location. In situ measurements of sediment oxygen demand in the Saddle River and Salem River watersheds ranged from 0.8 to 1.4 g/m2d (grams per square meter per day) and from 0.6 to 7.1 g/m2d at 20 degrees Celsius, respectively. Except at one site in this study, rates of sediment oxygen demand generally were low. The highest rate of sediment oxygen demand measured during this investigation, 7.1 g/m2d, which occurred at Courses Landing in the Salem River Basin, may be attributable to the consumption of oxygen by a large amount of organic matter (54 grams per kilogram as organic carbon) in the streambed sediments or to potential error during data collection. In general, sediment oxygen demand increased with the concentration of organic carbon in the streambed sediments. Repeated measurements made 6 to 7 days apart at the same site locations resulted in similar values.

Demand management and case management: a conservation strategy.

PubMed

Bryant, C D R Anna K

2007-01-01

This article reviews the history and development of managed competition, and explores the possibilities of a new demand management strategy in the context of nurse case management to offer less costly, higher quality care for a greater number of patients. The article examines the history and principles of healthcare demand management, its implementation in the hospital and clinical practices of nurse case managers, and its impacts in reducing costs while maintaining care levels. The article develops and analyzes the conflicts and common ground between demand management and case management. First, demand-side strategies can be effective in reducing costs while maintaining quality of nursing care; second, nurse case managers should employ patient education, self-care, and staffing solutions to manage demand. Nurse case managers must apply demand management principles carefully. Their goal is not to restrict care, but to maintain the highest levels of care possible within the limits of their practice's resources and staffing. Two critical themes emerge: (1) demand management is a potential alternative to market-driven managed competition and (2) nursing case management can affect an effective form of demand management. However, the long-term implications of these nursing case management strategies on healthcare staffing need further exploration.

Oral literacy demand of preventive dental visits in a pediatric medical office: a pilot study.

PubMed

Kranz, Ashley M; Pahel, Bhavna T; Rozier, R Gary

2013-01-01

The purpose of this study was to examine the oral literacy demands placed on parents of young children during preventive dental visits in a pediatric medical office. Transcripts of audio recordings for 15 pediatric medical visits were analyzed to assess the oral literacy demand of the visit, as measured by use of terminology, language complexity, and structural characteristics of the dialogue. Parent-completed surveys were used to determine recall of dental concepts discussed during the visit. Pearson's correlation coefficients were calculated to identify relationships among these measures and parental recall of the visit. Visits were interactive and used limited jargon and uncomplicated language. Oral literacy demand measures were associated with each other. Parental recall of the visit was associated with measures of high oral literacy demand. Assessing measures of oral literacy demand is a novel method for examining provider communication used during preventive dental visits in a pediatric medical office. Providers displayed low oral literacy demand when communicating with parents. Parental recall of dental concepts, however, was associated unexpectedly with higher oral literacy demand. Further research should examine a larger sample size and the effect of measures of oral literacy demand among low- and high-literacy patients.

A Longitudinal Test of the Demand–Control Model Using Specific Job Demands and Specific Job Control

PubMed Central

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

Estimating Ridership of Rural Demand-Response Transit Services for the General Public : 21177060-NCTR-NDSU08.

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...

The Aggregate Demand Curve: A Reply.

ERIC Educational Resources Information Center

Hansen, Richard B.; And Others

1987-01-01

Responds to claims about the instructional value of the downward-sloping aggregate demand curve in teaching principles of macroeconomics. Examines the effects of interest-rates and the role of money on demand curves. Concludes by arguing against the use of downward-sloping aggregate demand curves in textbooks. (RKM)

Definitions and Basic Concepts of Supply and Demand Analysis Used to Determine Market Equilibrium. Principles of Economics II (Microeconomics), Lesson Plan No. 6.

ERIC Educational Resources Information Center

Chiu-Irion, Vicky

Developed as part of a 37.5-hour microeconomics course, this lesson plan focuses on the concepts of supply and demand analysis used to determine market equilibrium. The objectives of the 50-minute lesson are to enable the student to: (1) explain how a demand schedule is derived from raw data; (2) graph a demand curve from the demand schedule; (3)…

Estimated Demand for Women's Health Services by 2020

PubMed Central

Dall, Timothy M.; Chakrabarti, Ritashree; Storm, Michael V.; Elwell, Erika C.

2013-01-01

Abstract Objective To estimate the demand for women's health care by 2020 using today's national utilization standards. Methods This descriptive study incorporated the most current national data resources to design a simulation model to create a health and economic profile for a representative sample of women from each state. Demand was determined utilizing equations about projected use of obstetrics-gynecology (ob-gyn) services. Applying patient profile and health care demand equations, we estimated the demand for providers in 2010 in each state for comparison with supply based on the 2010 American Medical Association Masterfile. U.S. Census Bureau population projections were used to project women's health care demands in 2020. Results The national demand for women's health care is forecast to grow by 6% by 2020. Most (81%) ob-gyn related services will be for women of reproductive age (18–44 years old). Growth in demand is forecast to be highest in states with the greatest population growth (Texas, Florida), where supply is currently less than adequate (western United States), and among Hispanic women. This increase in demand by 2020 will translate into a need for physicians or nonphysician clinicians, which is clinically equivalent to 2,090 full-time ob-gyns. Conclusion Using today's national norms of ob-gyn related services, a modest growth in women's health care demands is estimated by 2020 that will require a larger provider workforce. PMID:23829185

Estimated demand for women's health services by 2020.

PubMed

Dall, Timothy M; Chakrabarti, Ritashree; Storm, Michael V; Elwell, Erika C; Rayburn, William F

2013-07-01

To estimate the demand for women's health care by 2020 using today's national utilization standards. This descriptive study incorporated the most current national data resources to design a simulation model to create a health and economic profile for a representative sample of women from each state. Demand was determined utilizing equations about projected use of obstetrics-gynecology (ob-gyn) services. Applying patient profile and health care demand equations, we estimated the demand for providers in 2010 in each state for comparison with supply based on the 2010 American Medical Association Masterfile. U.S. Census Bureau population projections were used to project women's health care demands in 2020. The national demand for women's health care is forecast to grow by 6% by 2020. Most (81%) ob-gyn related services will be for women of reproductive age (18-44 years old). Growth in demand is forecast to be highest in states with the greatest population growth (Texas, Florida), where supply is currently less than adequate (western United States), and among Hispanic women. This increase in demand by 2020 will translate into a need for physicians or nonphysician clinicians, which is clinically equivalent to 2,090 full-time ob-gyns. Using today's national norms of ob-gyn related services, a modest growth in women's health care demands is estimated by 2020 that will require a larger provider workforce.

Interrelationships between Marijuana Demand and Discounting of Delayed Rewards: Convergence in Behavioral Economic Methods

PubMed Central

Aston, Elizabeth R.; Metrik, Jane; Amlung, Michael; Kahler, Christopher W.; MacKillop, James

2016-01-01

Background Distinct behavioral economic domains, including high perceived drug value (demand) and delay discounting (DD), have been implicated in the initiation of drug use and the progression to dependence. However, it is unclear whether frequent marijuana users conform to a “reinforcer pathology” addiction model wherein marijuana demand and DD jointly increase risk for problematic marijuana use and cannabis dependence (CD). Methods Participants (n=88, 34% female, 14% cannabis dependent) completed a marijuana purchase task at baseline. A delay discounting task was completed following placebo marijuana cigarette (0% THC) administration during a separate experimental session. Results Marijuana demand and DD were quantified using area under the curve (AUC). In multiple regression models, demand uniquely predicted frequency of marijuana use while DD did not. In contrast, DD uniquely predicted CD symptom count while demand did not. There were no significant interactions between demand and DD in either model. Conclusions These findings suggest that frequent marijuana users exhibit key constituents of the reinforcer pathology model: high marijuana demand and steep discounting of delayed rewards. However, demand and DD appear to be independent rather than synergistic risk factors for elevated marijuana use and risk for progression to CD. Findings also provide support for using AUC as a singular marijuana demand metric, particularly when also examining other behavioral economic constructs that apply similar statistical approaches, such as DD, to support analytic methodological convergence. PMID:27810657

Avoiding the conflict: Metacognitive awareness drives the selection of low-demand contexts.

PubMed

Desender, Kobe; Buc Calderon, Cristian; Van Opstal, Filip; Van den Bussche, Eva

2017-07-01

Previous research attempted to explain how humans strategically adapt behavior in order to achieve successful task performance. Recently, it has been suggested that 1 potential strategy is to avoid tasks that are too demanding. Here, we report 3 experiments that investigate the empirically neglected role of metacognitive awareness in this process. In these experiments, participants could freely choose between performing a task in either a high-demand or a low-demand context. Using subliminal priming, we ensured that participants were not aware of the visual stimuli creating these different demand contexts. Our results showed that participants who noticed a difference in task difficulty (i.e., metacognitive aware participants) developed a clear preference for the low-demand context. In contrast, participants who experienced no difference in task difficulty (i.e., metacognitive unaware participants) based their choices on variables unrelated to cognitive demand (e.g., the color or location associated with a context), and did not develop a preference for the low-demand context. Crucially, this pattern was found despite identical task performance in both metacognitive awareness groups. A multiple regression approach confirmed that metacognitive awareness was the main factor driving the preference for low-demand contexts. These results argue for an important role of metacognitive awareness in the strategic avoidance of demanding tasks. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Quantitative work demands, emotional demands, and cognitive stress symptoms in surgery nurses.

PubMed

Elfering, Achim; Grebner, Simone; Leitner, Monika; Hirschmüller, Anja; Kubosch, Eva Johanna; Baur, Heiner

2017-06-01

In surgery, cognitive stress symptoms, including problems in concentrating, deciding, memorising, and reflecting are risks to patient safety. Recent evidence points to social stressors as antecedents of cognitive stress symptoms in surgery personnel. The current study tests whether cognitive stress symptoms are positively associated with emotional abuse, emotional- and task-related demands and resources in surgery work. Forty-eight surgery nurses from two hospitals filled out the Copenhagen Psychosocial Questionnaire in its German version. Task-related and emotional demands were positively related to cognitive stress symptoms. In a stepwise, multiple, linear regression of cognitive stress symptoms on task-related and emotional demands, emotional abuse and emotional demands were unique predictors (p < .05). Efforts to increase patient safety should address emotional abuse, emotional demands, and, therefore, communication and cooperation team climate in surgery personnel.

Emotional adjustment and distressed interpersonal relations among low-income African American mothers: moderating effects of demanding kin relations.

PubMed

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.

Transportation Energy Futures Series: Freight Transportation Demand: Energy-Efficient Scenarios for a Low-Carbon Future

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grenzeback, L. R.; Brown, A.; Fischer, M. J.

2013-03-01

Freight transportation demand is projected to grow to 27.5 billion tons in 2040, and by extrapolation, to nearly 30.2 billion tons in 2050, requiring ever-greater amounts of energy. This report describes the current and future demand for freight transportation in terms of tons and ton-miles of commodities moved by truck, rail, water, pipeline, and air freight carriers. It outlines the economic, logistics, transportation, and policy and regulatory factors that shape freight demand; the possible trends and 2050 outlook for these factors, and their anticipated effect on freight demand and related energy use. After describing federal policy actions that could influencemore » freight demand, the report then summarizes the available analytical models for forecasting freight demand, and identifies possible areas for future action.« less

The Feeding Demands Questionnaire: Assessment of Parental Demand Cognitions Concerning Parent–Child Feeding Relations

PubMed Central

FAITH, MYLES S.; STOREY, MEGAN; KRAL, TANJA V. E.; PIETROBELLI, ANGELO

2010-01-01

Background There are few validated instruments measuring parental beliefs about parent–child feeding relations and child compliance during meals. Objective To test the validity of the Feeding Demands Questionnaire, a parent-report instrument designed to measure parents’ beliefs about how their child should eat. Methods Participants were 85 mothers of 3- to 7-year-old same-sex twin pairs or sibling pairs, and their children. Mothers completed the eight-item Feeding Demands Questionnaire and the Child Feeding Questionnaire, plus measures of depression and fear of fat. Statistical analyses Psychometric evaluations of the Feeding Demands Questionnaire included principal components analysis, Cronbach’s α for internal consistency, tests for convergent and discriminant validities, and Flesh-Kincaid for readability. Results The Feeding Demands Questionnaire had three underlying factors: anger/frustration, food amount demandingness, and food type demandingness, for which subscales were computed. The Feeding Demands Questionnaire showed acceptable internal consistency (α ranging from .70 to .86) and was written at the 4.8th grade level. Mothers reporting greater anger/frustration during feeding were more likely to pressure their children to eat, while those reporting greater demands about the type of foods their children eat were more likely to monitor child fat intake. Mothers reporting greater demands about the amount of food their children eat were more likely to restrict eating, pressure children to eat, and monitor their fat intake. Conclusions The Feeding Demands Questionnaire appears valid for assessing maternal beliefs that children should comply with rules for eating and frustration during feeding. Different demand beliefs can underlie different feeding practices. PMID:18375218

Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control

PubMed Central

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

The Impact of the Economy and Recessions on the Marketplace Demand for Ophthalmologists (An American Ophthalmological Society Thesis)

PubMed Central

Adelman, Ron A.; Nwanze, Chukwuemeka C.

2011-01-01

Purpose To develop a help-wanted index (HWI) to measure trends in marketplace demand for ophthalmologists, to identify the economic drivers of demand, and to determine the impact of economic recessions on the ophthalmology job market. Methods Review of physician recruitment advertisements appearing in the journals Ophthalmology, American Journal of Ophthalmology, and Archives of Ophthalmology from January 1980 through June 2006. Results Over the 26-year study period a consistent increase in the demand for subspecialists (31% of HWI in 1980 to 80% in 2005) was noted. There was also an increase in the demand for academic ophthalmologists. The need for academic ophthalmologists seems to be correlated with national research expenditure and stock market gains (P = .00191), whereas demand for private practice ophthalmologists seems to be correlated with the national economic well-being, as measured by gross domestic product (GDP) (P < .001). Residency applicants (P = .0128) and fellowship applicants (P = .0198) respond to marketplace demand. During the recessions, the demand for ophthalmologists fell 2 to 3 years after the economic downturn. Conclusions Over a 26-year period, HWI data suggest an increased need for subspecialists and academic ophthalmologists. The ophthalmic community has been quick to respond to marketplace demand. National research expenditure, stock market gains, GDP, and discretionary health care expenditure have been associated with the ophthalmology job market. These factors tend to decline with economic recessions. Historically, the demand for ophthalmologists has declined 2 to 3 years following a recession, which may mean lower demand in the near future, given the recent recession. PMID:22253483

Moderators of the relationship between frequent family demands and inflammation among adolescents.

PubMed

Levine, Cynthia S; Hoffer, Lauren C; Chen, Edith

2017-05-01

Frequent demands from others in relationships are associated with worse physiological and health outcomes. The present research investigated 2 potential moderators of the relationship between frequency of demands from one's family and inflammatory profiles among adolescents: (a) closeness of adolescents' relationships with their families, and (b) the frequency with which adolescents provided help to their families. Two hundred thirty-four adolescents, ages 13-16 (Mage = 14.53; 47.83% male), completed a daily dairy in which they reported on the frequency of demands made by family members. They were also interviewed about the closeness of their family relationships and reported in the daily diary on how frequently they provided help to their families. Adolescents also underwent a blood draw to assess low-grade inflammation and proinflammatory cytokine production in response to bacterial stimulation. More frequent demands from family predicted higher levels of low-grade inflammation and cytokine production in response to bacterial stimulation in adolescents. Family closeness moderated the relationship between frequent demands and stimulated cytokine production such that more frequent demands predicted higher cytokine production among adolescents who were closer to their families. Furthermore, frequency of providing help moderated the relationship between frequent demands and both low-grade inflammation and stimulated cytokine production, such that more frequent demands predicted worse inflammatory profiles among adolescents who provided more help to their families. These findings build on previous work on family demands and health to show under what circumstances family demands might have a physiological cost. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands.

PubMed

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.

Stimulus selectivity of drug purchase tasks: A preliminary study evaluating alcohol and cigarette demand.

PubMed

Strickland, Justin C; Stoops, William W

2017-06-01

The use of drug purchase tasks to measure drug demand in human behavioral pharmacology and addiction research has proliferated in recent years. Few studies have systematically evaluated the stimulus selectivity of drug purchase tasks to demonstrate that demand metrics are specific to valuation of or demand for the commodity under study. Stimulus selectivity is broadly defined for this purpose as a condition under which a specific stimulus input or target (e.g., alcohol, cigarettes) is the primary determinant of behavior (e.g., demand). The overall goal of the present study was to evaluate the stimulus selectivity of drug purchase tasks. Participants were sampled from the Amazon.com's crowdsourcing platform Mechanical Turk. Participants completed either alcohol and soda purchase tasks (Experiment 1; N = 139) or cigarette and chocolate purchase tasks (Experiment 2; N = 46), and demand metrics were compared to self-reported use behaviors. Demand metrics for alcohol and soda were closely associated with commodity-similar (e.g., alcohol demand and weekly alcohol use) but not commodity-different (e.g., alcohol demand and weekly soda use) variables. A similar pattern was observed for cigarette and chocolate demand, but selectivity was not as consistent as for alcohol and soda. Collectively, we observed robust selectivity for alcohol and soda purchase tasks and modest selectivity for cigarette and chocolate purchase tasks. These preliminary outcomes suggest that demand metrics adequately reflect the specific commodity under study and support the continued use of purchase tasks in substance use research. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The impact of the economy and recessions on the marketplace demand for ophthalmologists (an American Ophthalmological Society thesis).

PubMed

Adelman, Ron A; Nwanze, Chukwuemeka C

2011-12-01

To develop a help-wanted index (HWI) to measure trends in marketplace demand for ophthalmologists, to identify the economic drivers of demand, and to determine the impact of economic recessions on the ophthalmology job market. Review of physician recruitment advertisements appearing in the journals Ophthalmology, American Journal of Ophthalmology, and Archives of Ophthalmology from January 1980 through June 2006. Over the 26-year study period a consistent increase in the demand for subspecialists (31% of HWI in 1980 to 80% in 2005) was noted. There was also an increase in the demand for academic ophthalmologists. The need for academic ophthalmologists seems to be correlated with national research expenditure and stock market gains (P = .00191), whereas demand for private practice ophthalmologists seems to be correlated with the national economic well-being, as measured by gross domestic product (GDP) (P < .001). Residency applicants (P = .0128) and fellowship applicants (P = .0198) respond to marketplace demand. During the recessions, the demand for ophthalmologists fell 2 to 3 years after the economic downturn. Over a 26-year period, HWI data suggest an increased need for subspecialists and academic ophthalmologists. The ophthalmic community has been quick to respond to marketplace demand. National research expenditure, stock market gains, GDP, and discretionary health care expenditure have been associated with the ophthalmology job market. These factors tend to decline with economic recessions. Historically, the demand for ophthalmologists has declined 2 to 3 years following a recession, which may mean lower demand in the near future, given the recent recession.

Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control.

PubMed

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.

Relative effects of demand and control on task-related cardiovascular reactivity, task perceptions, performance accuracy, and mood.

PubMed

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.

Age and sex differences in steadiness of elbow flexor muscles with imposed cognitive demand

PubMed Central

Pereira, Hugo M.; Spears, Vincent C.; Schlinder-Delap, Bonnie; Yoon, Tejin; Nielson, Kristy A.; Hunter, Sandra K.

2015-01-01

Purpose These studies determined (1) age and sex-related differences in steadiness of isometric contractions when high cognitive demand was imposed across a range of forces with the elbow flexor muscles (study 1) and, (2) sex differences in steadiness among older adults when low cognitive demand was imposed (study 2). Methods 36 young adults (18–25 years; 18 women) and 30 older adults (60–82 years; 17 women) performed isometric contractions at 5%, 30% and 40% of maximum voluntary contraction (MVC). Study 1 involved a high-cognitive demand session (serial subtractions by 13 during the contraction) and a control session (no mental math). Study 2 (older adults only) involved a low-cognitive demand session (subtracting by 1s). Results Older individuals exhibited greater increases in force fluctuations (coefficient of variation of force, CV) with high cognitive demand than young adults, with the largest age difference at 5% MVC (P = 0.01). Older adults had greater agonist EMG activity with high-cognitive demand and women had greater coactivation than men (P<0.05). In study 2, CV of force increased with low cognitive demand for the older women but not for the older men (P = 0.03). Conclusion Older adults had reduced steadiness and increased muscle activation when high cognitive demand was imposed while low cognitive demand induced increased force fluctuations in older women but not older men. These findings have implications for daily and work-related tasks that involve cognitive demand performed simultaneously during submaximal isometric contractions in an aging workforce. PMID:25633070

Revisions to the Wharton EFA Automobile Demand Model : The Wharton EFA Motor Vehicle Demand Model (Mark I)

DOT National Transportation Integrated Search

1980-12-01

The report documents revisions made to the Wharton EFA Automobile Demand Model to produce the Wharton EFA Motor Vehicle Demand Model (Mark I). Equations are reestimated for the total desired stock of autos and for desired shares by size class, includ...

22 CFR 512.9 - Demand for payment.

Code of Federal Regulations, 2010 CFR

2010-04-01

... administrative offset, demand for payment will be made as follows: (a) Written demands will be made promptly upon... three progressively stronger written demands at not more than 30-day intervals will normally be made... Goverment's interests (e.g., to prevent the statute of limitations, 28 U.S.C. 2415, from expiring) written...

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...

7 CFR 981.21 - Trade demand.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Trade demand. 981.21 Section 981.21 Agriculture... Regulating Handling Definitions § 981.21 Trade demand. Trade demand means the quantity of almonds..., bakery, ice cream, and nut salting trades will acquire from all handlers during a crop year for...

7 CFR 981.21 - Trade demand.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Trade demand. 981.21 Section 981.21 Agriculture... Regulating Handling Definitions § 981.21 Trade demand. Trade demand means the quantity of almonds..., bakery, ice cream, and nut salting trades will acquire from all handlers during a crop year for...

7 CFR 981.21 - Trade demand.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Trade demand. 981.21 Section 981.21 Agriculture... Regulating Handling Definitions § 981.21 Trade demand. Trade demand means the quantity of almonds..., bakery, ice cream, and nut salting trades will acquire from all handlers during a crop year for...

7 CFR 981.21 - Trade demand.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Trade demand. 981.21 Section 981.21 Agriculture... Regulating Handling Definitions § 981.21 Trade demand. Trade demand means the quantity of almonds..., bakery, ice cream, and nut salting trades will acquire from all handlers during a crop year for...

Application of Demand Analysis in Marketing Continuing Education.

ERIC Educational Resources Information Center

Waters, Elzberry, Jr.

This study investigated the feasibility of applying economic demand analysis (especially elasticity of demand) in marketing George Washington University off-campus degree programs. In the case under study, a supplemental budget request had to be submitted to meet expenses incurred by an unforeseen increase in demand for graduate and undergraduate…

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

Code of Federal Regulations, 2011 CFR

2011-10-01

... and without excessive wear of the moving parts. The demand or pressure-demand valve shall not be... a force of 90 kg. (200 pounds) is applied for 5 minutes between 2 planes 7.6 cm. (3 inches) wide on...

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

Code of Federal Regulations, 2012 CFR

2012-10-01

... and without excessive wear of the moving parts. The demand or pressure-demand valve shall not be... a force of 90 kg. (200 pounds) is applied for 5 minutes between 2 planes 7.6 cm. (3 inches) wide on...

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

Code of Federal Regulations, 2014 CFR

2014-10-01

... and without excessive wear of the moving parts. The demand or pressure-demand valve shall not be... a force of 90 kg. (200 pounds) is applied for 5 minutes between 2 planes 7.6 cm. (3 inches) wide on...

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

Code of Federal Regulations, 2013 CFR

2013-10-01

... and without excessive wear of the moving parts. The demand or pressure-demand valve shall not be... a force of 90 kg. (200 pounds) is applied for 5 minutes between 2 planes 7.6 cm. (3 inches) wide on...

International Demand for American Higher Education: An Extension.

ERIC Educational Resources Information Center

Mixon, J. Wilson, Jr.; Wan, Weidong

1990-01-01

A study of the relationship of population and income in Asian countries and Organization of Petroleum Exporting Countries (OPEC) members to their demand for American higher education found that both population and income significantly affect demand, but not proportionally. Findings suggest countries meet most change in citizens' demand with…

29 CFR 20.78 - Notifications.

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...

14 CFR 135.4 - Applicability of rules for eligible on-demand operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

...-demand operations. 135.4 Section 135.4 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... OPERATIONS OPERATING REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT General § 135.4 Applicability of rules for eligible on-demand operations. (a) An...

29 CFR 20.78 - Notifications.

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...

Methods for and estimates of 2003 and projected water use in the Seacoast Region, Southeastern New Hampshire

USGS Publications Warehouse

Horn, Marilee A.; Moore, Richard B.; Hayes, Laura; Flanagan, Sarah M.

2008-01-01

New methods were developed to estimate water use in 2003 and future water demand in 2017 and 2025 in the Seacoast region in southeastern New Hampshire, which has experienced a 37-percent population increase during 1980 to 2000. Water-use activities for which estimates were developed include water withdrawal, delivery, demand, consumptive use, release, return flow, and transfer by registered and aggregated unregistered (less than 20,000 gallons per day (gal/d)) users at the census-block and town scales. Estimates of water use rely on understanding what influences water demand and its associated consumptive use, because changes in demand and consumptive use affect withdrawal and return flow. Domestic water demand was estimated using a per capita water demand model that related metered deliveries to domestic users with census block and block-group data. The model was used to predict annual, summer, and winter per capita water-demand coefficients for each census block. Significant predictors of domestic water demand include population per housing unit, median value of owner-occupied single family homes, median year of housing construction (with 1900 as the base value), population density, housing unit density, and proportion of housing units that are in urban areas. Mean annual domestic per capita water-demand coefficient in the Seacoast region was 75 gal/d; the coefficient increased to 91 gal/d during the summer and decreased to 65 gal/d during the winter. Domestic consumptive use was estimated as the difference between annual and winter domestic water demand. Estimates of commercial and industrial water demand were based on coefficients derived from reported use and metered deliveries. Projections of water demand in 2017 and 2025 were determined by using the housing and employee projections for those years developed through a Transportation Demand Model and applying current domestic and non-domestic coefficients. Water demand in 2003 was estimated as 25.8 million gallons per day (Mgal/d), 35 percent of which was during the summer months of June, July, and August. Domestic water demand was 18.6 Mgal/d (72 percent), commercial water demand was 3.7 Mgal/d (14 percent), industrial water demand was 2.9 Mgal/d (11 percent), irrigation water demand was 0.3 Mgal/d (1 percent), and mining and aquaculture water demand was 0.2 Mgal/d (1 percent). Domestic consumptive use for the Seacoast region was 16 percent of domestic water demand, which translates to a loss of 3 Mgal/d over the entire Seacoast region. In 2003, water withdrawal was 771.2 Mgal/d, of which 742.2 Mgal/d was instream use for hydroelectric power generation and thermoelectric power cooling. The remaining 29.0 Mgal/d was withdrawn by community water systems (22.6 Mgal/d; 72 percent), domestic users (6.4 Mgal/d; 21 percent), commercial users (1.0 Mgal/d; 3 percent), industrial users (1.0 Mgal/d; 3 percent), irrigation (0.2 Mgal/d; 1 percent) and other users (less than 0.1 Mgal/d). Return flow for 2003 was 772.2 Mgal/d, of which 742.0 Mgal/d was returned following use for hydroelectric power generation and thermoelectric plant cooling. The remaining 30.2 Mgal/d was returned by community wastewater systems (20.2 Mgal/d; 68 percent), domestic users (7.8 Mgal/d; 26 percent), commercial users (1.2 Mgal/d; 3 percent), industrial users (0.8 Mgal/d; 3 percent), and other users (0.1 Mgal/d). Domestic water demand is projected to increase by 54 percent to 28.7 Mgal/d from 2003 to 2025 based on projection of future population growth. Non-domestic (commercial, industrial, irrigation, and mining) water demand is projected to increase by 66 percent to 11.8 Mgal/d from 2003 to 2025.

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.

How to introduce demand side resources in the design of low-carbon power systems in China

NASA Astrophysics Data System (ADS)

Zhou, Pengcheng; Liu, Yiqun; Zeng, Ming; Sun, Chenjun

2018-04-01

Nowadays, China's energy demand sustained rapid growth, and the coal-based energy structure has adverse effects on the environment. The flexibility of demand side resource (DSR) will be greatly improved, and DSR can reduce electricity consumption actively and temporarily, and realize energy saving and emission reduction. But there are still some problems to introduce DSR in China. This paper proposes three practices for introducing demand side resources to improve the flexibility of power systems through demand resources.

A Framework to Determine New System Requirements Under Design Parameter and Demand Uncertainties

DTIC Science & Technology

2015-05-13

Demand fluctuation on a day to day basis – Routes flown vary based on demand – Limited aircraft types: C-5, C-17, C-130, Boeing 747 -F, KC-135, etc...dataset – Demand for subset served by C-5, C-17 and 747 -F (~75% of total demand) – Fixed density and dimension of pallet (463 L) • Our aircraft...fleet consists of only the C-5, C-17 and 747 -F. Source: www.amc.af.mil 30

Communications to 2000 - A forecast of the demand and capacity of U.S. domestic communications satellites

NASA Astrophysics Data System (ADS)

Fordyce, S. W.

The market demand for the U.S. domestic communications satellites accelerated in the late 70's, exceeding the capacity of the satellites currently in orbit. Satellite carriers have been authorized to build an additional 24 domsats. This paper examines the anticipated market demands, and the capability of the domsats to fulfill these demands. With various practical technical innovations, the domsats appear able to meet the expected market demands until the end of this century.

Estimating demand for alternatives to cigarettes with online purchase tasks.

PubMed

O'Connor, Richard J; June, Kristie M; Bansal-Travers, Maansi; Rousu, Matthew C; Thrasher, James F; Hyland, Andrew; Cummings, K Michael

2014-01-01

To explore how advertising affects demand for cigarettes and potential substitutes, including snus, dissolvable tobacco, and medicinal nicotine. A Web-based experiment randomized 1062 smokers to see advertisements for alternative nicotine products or soft drinks, then complete a series of purchase tasks, which were used to estimate demand elasticity, peak consumption, and cross-price elasticity (CPE) for tobacco products. Lower demand elasticity and greater peak consumption were seen for cigarettes compared to all alternative products (p < .05). CPE did not differ across the alternative products (p ≤ .03). Seeing relevant advertisements was not significantly related to demand. These findings suggest significantly lower demand for alternative nicotine sources among smokers than previously revealed.

Skills-demands compatibility as a determinant of flow experience in an inductive reasoning task.

PubMed

Schiefele, Ulrich; Raabe, Andreas

2011-10-01

The skills-demands fit hypothesis of flow theory was examined. Based on the earlier finding that high demands in a game situation do not reduce the experience of flow, a cognitive task paradigm was used. The effect of skills-demands compatibility on the experience of flow but not of other, similar psychological states (i.e., concentration, negative and positive activation) was also investigated. Participants were 89 undergraduate students who worked on a number of inductive reasoning tasks in four successive trials with or without skills-demands compatibility. The results clearly supported the skills-demands fit hypothesis; concentration and activation were affected only by the tasks' difficulty. Inductive reasoning tasks are a useful tool for the experimental analysis of flow, and skills-demands compatibility is a significant and powerful condition of flow, but not of other, similar psychological states.

Transportation Energy Futures Series: Freight Transportation Demand: Energy-Efficient Scenarios for a Low-Carbon Future

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grenzeback, L. R.; Brown, A.; Fischer, M. J.

2013-03-01

Freight transportation demand is projected to grow to 27.5 billion tons in 2040, and to nearly 30.2 billion tons in 2050. This report describes the current and future demand for freight transportation in terms of tons and ton-miles of commodities moved by truck, rail, water, pipeline, and air freight carriers. It outlines the economic, logistics, transportation, and policy and regulatory factors that shape freight demand, the trends and 2050 outlook for these factors, and their anticipated effect on freight demand. After describing federal policy actions that could influence future freight demand, the report then summarizes the capabilities of available analyticalmore » models for forecasting freight demand. This is one in a series of reports produced as a result of the Transportation Energy Futures project, a Department of Energy-sponsored multi-agency effort to pinpoint underexplored strategies for reducing GHGs and petroleum dependence related to transportation.« less

The Relationship between Job Demands and Employees' Counterproductive Work Behaviors: The Mediating Effect of Psychological Detachment and Job Anxiety.

PubMed

Chen, Yang; Li, Shuang; Xia, Qing; He, Chao

2017-01-01

This study aims to explore the relation between job demands and counterproductive work behaviors (CWBs). A cross-sectional sample of 439 coal miners completed a self-report questionnaire that assessed their job demands, psychological detachment, job anxiety, and CWBs in a Chinese context. The conceptual model, based on the stressor-detachment model, was examined using structural equation modeling. The results suggest that psychological detachment mediates not only the relation between job demands and job anxiety but also that between job demands and CWBs. Furthermore, the relation between job demands and CWBs is sequentially mediated by psychological detachment and job anxiety. Our findings validate the effectiveness of the stressor-detachment model. Moreover, we demonstrate that the underlying mechanism of the relation between job demands and CWBs can be explained by psychological detachment and job anxiety.

Railing for safety: job demands, job control, and safety citizenship role definition.

PubMed

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.

The Relationship between Job Demands and Employees’ Counterproductive Work Behaviors: The Mediating Effect of Psychological Detachment and Job Anxiety

PubMed Central

Chen, Yang; Li, Shuang; Xia, Qing; He, Chao

2017-01-01

This study aims to explore the relation between job demands and counterproductive work behaviors (CWBs). A cross-sectional sample of 439 coal miners completed a self-report questionnaire that assessed their job demands, psychological detachment, job anxiety, and CWBs in a Chinese context. The conceptual model, based on the stressor-detachment model, was examined using structural equation modeling. The results suggest that psychological detachment mediates not only the relation between job demands and job anxiety but also that between job demands and CWBs. Furthermore, the relation between job demands and CWBs is sequentially mediated by psychological detachment and job anxiety. Our findings validate the effectiveness of the stressor-detachment model. Moreover, we demonstrate that the underlying mechanism of the relation between job demands and CWBs can be explained by psychological detachment and job anxiety. PMID:29163274

Exploring the Factor Structure of the Job Demands-Resources Measure With Patient Violence on Direct Care Workers in the Home Setting.

PubMed

Byon, Ha Do; Harrington, Donna; Storr, Carla L; Lipscomb, Jane

2017-08-01

Workplace violence research in health care settings using the Job Demands-Resources (JD-R) framework is hindered by the lack of comprehensive examination of the factor structure of the JD-R measure when it includes patient violence. Is patient violence a component of job demands or its own factor as an occupational outcome? Exploratory factor analysis and confirmatory factor analysis were conducted using a sample of direct care workers in the home setting (n = 961). The overall 2-construct JD-R structure persisted. Patient violence was not identified as a separate factor from job demands; rather, two demand factors emerged: violence/emotional and workload/physical demands. Although the three-factor model fits the data, the two-factor model with patient violence being a component of job demands is a parsimonious and effective measurement framework.

Incorporating home demands into models of job strain: findings from the work, family, and health network.

PubMed

Ertel, Karen A; Koenen, Karestan C; Berkman, Lisa F

2008-11-01

The purpose of this article was to integrate home demands with the demand-control-support model to test if home demands interact with job strain to increase depressive symptoms. Data were from 431 employees in four extended care facilities. Presence of a child younger than 18 years in the household signified home demands. The outcome was depressive symptoms based on a shortened version of the Center for Epidemiologic Studies Depression Scale. The association between job strain and depressive symptoms was moderated by social support (SS) and presence of a child in the household (child). There was no association among participants with high SS and no child, but a positive one among participants with low SS and a child. Job strain may be a particularly important determinant of depressive symptoms among employees with family demands. Models of job strain should expand to incorporate family demands.

The Impact of Physical Work Demands on Need for Recovery, Employment Status, Retirement Intentions, and Ability to Extend Working Careers: A Longitudinal Study Among Older Workers.

PubMed

Gommans, Fleur G; Jansen, Nicole W H; Mackey, Martin G; Stynen, Dave; de Grip, Andries; Kant, I Jmert

2016-04-01

Prospectively investigating whether different approaches of physical work demands are associated with need for recovery (NFR), employment status, retirement intentions, and ability to prolong working life among older employees from the industry and health care sector. A subsample from the Maastricht Cohort Study was studied (n = 1126). Poisson, Cox, and logistic regression analyses were performed to investigate outcomes. Perceiving physical work demands as strenuous was associated with higher NFR. Continuous physical strain was associated with being out of employment 4 years later. Employees with the highest amount of physical work demands perceived they were less able to prolong working life, although no significant associations between physical work demands and retirement intentions were found. Overall, physical work demands were associated with adverse outcomes, with divergent insights for the different approaches of physical work demands.

A novel medical information management and decision model for uncertain demand optimization.

PubMed

Bi, Ya

2015-01-01

Accurately planning the procurement volume is an effective measure for controlling the medicine inventory cost. Due to uncertain demand it is difficult to make accurate decision on procurement volume. As to the biomedicine sensitive to time and season demand, the uncertain demand fitted by the fuzzy mathematics method is obviously better than general random distribution functions. To establish a novel medical information management and decision model for uncertain demand optimization. A novel optimal management and decision model under uncertain demand has been presented based on fuzzy mathematics and a new comprehensive improved particle swarm algorithm. The optimal management and decision model can effectively reduce the medicine inventory cost. The proposed improved particle swarm optimization is a simple and effective algorithm to improve the Fuzzy interference and hence effectively reduce the calculation complexity of the optimal management and decision model. Therefore the new model can be used for accurate decision on procurement volume under uncertain demand.

ELECTRICAL LOAD ANTICIPATOR AND RECORDER

DOEpatents

Werme, J.E.

1961-09-01

A system is described in which an indication of the prevailing energy consumption in an electrical power metering system and a projected power demand for one demand in terval is provided at selected increments of time within the demand interval. Each watt-hour meter in the system is provided with an impulse generator that generates two impulses for each revolution of the meter disc. In each demand interval, for example, one half-hour, of the metering system, the total impulses received from all of the meters are continuously totaled for each 5-minute interval and multiplied by a number from 6 to 1 depending upon which 5- minute interval the impulses were received. This value is added to the total pulses received in the intervals preceding the current 5-minute interval within the half-hour demand interval tc thereby provide an indication of the projected power demand every 5 minutes in the demand interval.

Job Demands, Job Resources, Burnout, Work Engagement, and Their Relationships: An Analysis Across Sectors.

PubMed

Van den Broeck, Anja; Elst, Tinne Vander; Baillien, Elfi; Sercu, Maarten; Schouteden, Martijn; De Witte, Hans; Godderis, Lode

2017-04-01

The aim of this study was to gain insight in the importance of job demands and resources and the validity of the Job Demands Resources Model across sectors. We used one-way analyses of variance to examine mean differences, and multi-group Structural Equation Modeling analyses to test the strength of the relationships among job demands, resources, burnout, and work engagement across the health care, industry, service, and public sector. The four sectors differed in the experience of job demands, resources, burnout, and work engagement, but they did not vary in how (strongly) job demands and resources associated with burnout and work engagement. More attention is needed to decrease burnout and increase work engagement, particularly in industry, service, and the public sector. The Job Demands-Resources model may be helpful in this regard, as it is valid across sectors.

29 CFR 1450.9 - Demand for payment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... below: (a) Written demands shall be made promptly upon a debtor in terms which inform the debtor of the consequences of failure to cooperate. A total of three progressively stronger written demands at not more than..., 28 U.S.C. 2415, from expiring), written demand may be preceded by other appropriate actions under...

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...

22 CFR 309.9 - Notice-written demand for payment.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Notice-written demand for payment. 309.9 Section 309.9 Foreign Relations PEACE CORPS DEBT COLLECTION Collection Actions § 309.9 Notice—written demand... the records of Peace Corps) at least one written notice (e.g. Bill of Collection or demand letter...

7 CFR 993.21b - Trade demand.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 8 2011-01-01 2011-01-01 false Trade demand. 993.21b Section 993.21b Agriculture... Order Regulating Handling Definitions § 993.21b Trade demand. (a) Domestic trade demand. The quantity of prunes which the commercial trade will acquire from all handlers during a crop year for distribution in...

7 CFR 993.21b - Trade demand.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 8 2014-01-01 2014-01-01 false Trade demand. 993.21b Section 993.21b Agriculture... Order Regulating Handling Definitions § 993.21b Trade demand. (a) Domestic trade demand. The quantity of prunes which the commercial trade will acquire from all handlers during a crop year for distribution in...

7 CFR 993.21b - Trade demand.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 8 2013-01-01 2013-01-01 false Trade demand. 993.21b Section 993.21b Agriculture... Order Regulating Handling Definitions § 993.21b Trade demand. (a) Domestic trade demand. The quantity of prunes which the commercial trade will acquire from all handlers during a crop year for distribution in...

Evaluating effects of travel demand management in a medium-sized urban area : the study of I-40 Greensboro-Winston-Salem corridor

DOT National Transportation Integrated Search

2001-08-01

Travel demand management (TDM) is a set of procedures that have been shown to alleviate unlimited use of automobiles. Demand is managed by limiting highway capacity to meet demand to travel by car and providing incentives or disincentives to increase...

Demand for resident hunting in the southeastern United States

Treesearch

Neelam Poudyal; Seong Hoon Cho; J. Michael Bowker

2008-01-01

We modeled hunting demand among resident hunters in the Southeastern United States. Our model revealed that future hunting demand will likely decline in this region. Population growth in the region will increase demand but structural change in the region's demography (e.g., "browning" and "aging "), along with declining forestland access will...

The effects of declining population growth on the demand for housing.

Treesearch

Thomas C. Marcin

1974-01-01

Declining population growth and unprecedented changes in the age structure of the population in the next several decades will profoundly affect housing demand in the next 50 years. A decline in housing demand and substantial change in the type of housing in demand are likely to occur by 1990.

27 CFR 70.81 - Notice and demand for tax.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Notice and demand for tax. 70.81 Section 70.81 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Excise and Special (Occupational) Tax Notice and Demand § 70.81 Notice and demand for tax. (a) General...

27 CFR 70.82 - Payment on notice and demand.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Payment on notice and demand. 70.82 Section 70.82 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE... Collection of Excise and Special (Occupational) Tax Notice and Demand § 70.82 Payment on notice and demand...

Conceptualizing and measuring demand for recreation on national forests: a review and synthesis.

Treesearch

Brian E. Garber-Yonts

2005-01-01

This analysis examines the problem of measuring demand for recreation on national forests and other public lands. Current measures of recreation demand in Forest Service resource assessments and planning emphasize population-level participation rates and activity-based economic values for visitor days. Alternative measures and definitions of recreation demand are...

5 CFR 295.203 - Filing requirements for demands or requests for documents or testimony.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Filing requirements for demands or....203 Filing requirements for demands or requests for documents or testimony. You must comply with the following requirements whenever you issue demands or requests to an OPM employee for official records and...

5 CFR 2608.203 - Filing requirements for demands or requests for documents or testimony.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Filing requirements for demands or....203 Filing requirements for demands or requests for documents or testimony. You must comply with the following requirements whenever you issue demands or requests to an OGE employee for official records and...

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...

5 CFR 2608.203 - Filing requirements for demands or requests for documents or testimony.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Filing requirements for demands or....203 Filing requirements for demands or requests for documents or testimony. You must comply with the following requirements whenever you issue demands or requests to an OGE employee for official records and...

Assessing the Utility of a Demand Assessment for Functional Analysis

ERIC Educational Resources Information Center

Roscoe, Eileen M.; Rooker, Griffin W.; Pence, Sacha T.; Longworth, Lynlea J.

2009-01-01

We evaluated the utility of an assessment for identifying tasks for the functional analysis demand condition with 4 individuals who had been diagnosed with autism. During the demand assessment, a therapist presented a variety of tasks, and observers measured problem behavior and compliance to identify demands associated with low levels of…

Enriched environment at work: Disassociated from stress and burnout.

PubMed

Rodriguez, Francisca S; Luck, Tobias; Riedel-Heller, Steffi G

2018-05-22

Enriched environment at work (EEW), in terms of high mental demands at work, may be of great relevance for preventative efforts against cognitive decline and dementia as previous studies have shown. Yet, there is the concern that high EEW mental demands may accelerate stress and cause burnout. The aim of our study was to investigate how EEW mental demands are related to stress and burnout. A convenience sample of employees in the city area of Leipzig, Germany, was asked to fill out the Copenhagen Burnout Inventory and indicate for each EEW mental demand the level experienced, demandingness, and stressfulness. Multivariate linear regression and structural equation modelling suggested that only some EEW mental demands were perceived as stressful when the level of the respective EEW mental demand was high. Higher stressfulness was associated with burnout symptoms - however, high levels of EEW mental demands were not significantly associated with burnout (neither directly nor indirectly). Our findings implied that subjectively perceived stressfulness seems to be a more relevant aspect than the actual level of the demand itself. However, further studies are necessary to validate our findings.

A hybrid inventory management system respondingto regular demand and surge demand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohammad S. Roni; Mingzhou Jin; Sandra D. Eksioglu

2014-06-01

This paper proposes a hybrid policy for a stochastic inventory system facing regular demand and surge demand. The combination of two different demand patterns can be observed in many areas, such as healthcare inventory and humanitarian supply chain management. The surge demand has a lower arrival rate but higher demand volume per arrival. The solution approach proposed in this paper incorporates the level crossing method and mixed integer programming technique to optimize the hybrid inventory policy with both regular orders and emergency orders. The level crossing method is applied to obtain the equilibrium distributions of inventory levels under a givenmore » policy. The model is further transformed into a mixed integer program to identify an optimal hybrid policy. A sensitivity analysis is conducted to investigate the impact of parameters on the optimal inventory policy and minimum cost. Numerical results clearly show the benefit of using the proposed hybrid inventory model. The model and solution approach could help healthcare providers or humanitarian logistics providers in managing their emergency supplies in responding to surge demands.« less

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

Economic concepts to address future water supply-demand imbalances in Iran, Morocco and Saudi Arabia

NASA Astrophysics Data System (ADS)

Hellegers, Petra; Immerzeel, Walter; Droogers, Peter

2013-10-01

In Middle East and North Africa (MENA) countries, renewable groundwater and surface water supply are limited while demand for water is growing rapidly. Climate change is expected to increase water demand even further. The main aim of this paper is to evaluate the water supply-demand imbalances in Iran, Morocco and Saudi Arabia in 2040-2050 under dry, average and wet climate change projections and to show on the basis of the marginal cost and marginal value of water the optimum mix of supply-side and demand-side adjustments to address the imbalance. A hydrological model has been used to estimate the water supply-demand imbalance. Water supply and demand curves have been used to explore for which (marginal value of) water usage the marginal cost of supply-enhancement becomes too expensive. The results indicate that in the future in all cases, except in Iran under the wet climate projection, the quantity of water demanded has to be reduced considerably to address the imbalance, which is indeed what is currently happening already.

The active learning hypothesis of the job-demand-control model: an experimental examination.

PubMed

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.

Influence of job demands and job control on work-life balance among Taiwanese nurses.

PubMed

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.

Burnout and Work Demands Predict Reduced Job Satisfaction in Health Professionals Working In a Surgery Clinic

PubMed Central

Mijakoski, Dragan; Karadzinska-Bislimovska, Jovanka; Basarovska, Vera; Stoleski, Sasho; Minov, Jordan

2015-01-01

BACKGROUND: Burnout syndrome develops in health professionals (HPs) as a result of exposure to chronic emotional and interpersonal workplace stressors. Research demonstrates the links between burnout, work demands, and job satisfaction in hospital HPs. AIMS: To examine the associations between burnout, work demands and job satisfaction, and to demonstrate the mediation effect of emotional exhaustion on the relationship between work demands and job satisfaction in surgery clinic HPs. METHODS: Maslach Burnout Inventory was used for assessment of burnout. Work demands and job satisfaction were measured with Hospital Experience Scale and Job Satisfaction Survey, respectively. In order to examine the role of emotional exhaustion, depersonalization, and work demands, controlling for age, hospital tenure, and unit tenure, a hierarchical multiple regression models were tested for each job satisfaction factor. RESULTS: Job satisfaction was negatively predicted by emotional exhaustion. Certain types of work demands negatively predicted different factors of job satisfaction. Emotional exhaustion was a significant partial mediator of the relationship between work demands and job satisfaction. CONCLUSIONS: Adequate management of work demands, particularly excessive workload, time pressure, and lack of staff can lead to prevention of burnout and reduced job satisfaction in surgery clinic HPs, and contribute to better quality of patient care. PMID:27275216

Driving monotonous routes in a train simulator: the effect of task demand on driving performance and subjective experience.

PubMed

Dunn, Naomi; Williamson, Ann

2012-01-01

Although monotony is widely recognised as being detrimental to performance, its occurrence and effects are not yet well understood. This is despite the fact that task-related characteristics, such as monotony and low task demand, have been shown to contribute to performance decrements over time. Participants completed one of two simulated train-driving scenarios. Both were highly monotonous and differed only in terms of the level of cognitive demand required (i.e. low demand or high demand). These results highlight the seriously detrimental effects of the combination of monotony and low task demands and clearly show that even a relatively minor increase in cognitive demand can mitigate adverse monotony-related effects on performance for extended periods of time. Monotony is an inherent characteristic of transport industries, including rail, aviation and road transport, which can have adverse impact on safety, reliability and efficiency. This study highlights possible strategies for mitigating these adverse effects. Practitioner Summary: This study provides evidence for the importance of cognitive demand in mitigating monotony-related effects on performance. The results have clear implications for the rapid onset of performance deterioration in low demand monotonous tasks and demonstrate that these detrimental performance effects can be overcome with simple solutions, such as making the task more cognitively engaging.

Area Under the Curve as a Novel Metric of Behavioral Economic Demand for Alcohol

PubMed Central

Amlung, Michael; Yurasek, Ali; McCarty, Kayleigh N.; MacKillop, James; Murphy, James G.

2015-01-01

Behavioral economic purchase tasks can be readily used to assess demand for a number of addictive substances including alcohol, tobacco and illicit drugs. However, several methodological limitations associated with the techniques used to quantify demand may reduce the utility of demand measures. In the present study, we sought to introduce area under the curve (AUC), commonly used to quantify degree of delay discounting, as a novel index of demand. A sample of 207 heavy drinking college students completed a standard alcohol purchase task and provided information about typical weekly drinking patterns and alcohol-related problems. Level of alcohol demand was quantified using AUC – which reflects the entire amount of consumption across all drink prices - as well as the standard demand indices (e.g., intensity, breakpoint, Omax, Pmax, and elasticity). Results indicated that AUC was significantly correlated with each of the other demand indices (rs = .42–.92), with particularly strong associations with Omax (r = .92). In regression models, AUC and intensity were significant predictors of weekly drinking quantity and AUC uniquely predicted alcohol-related problems, even after controlling for drinking level. In a parallel set of analyses, Omax also predicted drinking quantity and alcohol problems, although Omax was not a unique predictor of the latter. These results offer initial support for using AUC as an index of alcohol demand. Additional research is necessary to further validate this approach and to examine its utility in quantifying demand for other addictive substances such as tobacco and illicit drugs. PMID:25895013

Effects of bupropion on simulated demand for cigarettes and the subjective effects of smoking.

PubMed

Madden, Gregory J; Kalman, David

2010-04-01

The biobehavioral mechanism(s) mediating bupropion's efficacy are not well understood. Behavioral economic measures such as demand curves have proven useful in investigations of the reinforcing effects of drugs of abuse. Behavioral economic measures may also be used to measure the effect of pharmacotherapies on the reinforcing effects of drugs of abuse. The effects of bupropion on simulated demand for cigarettes were investigated in a placebo-controlled double-blind clinical trial. Participants reported the number of cigarettes they would purchase and consume in a single day at a range of prices. The effects of medication on the subjective effects of smoking were also explored. Demand for cigarettes was well described by an exponential demand equation. Bupropion did not significantly decrease the maximum number of cigarettes that participants said they would smoke in a single day nor did it significantly alter the relation between price per cigarette and demand. Baseline demand elasticity did not predict smoking cessation, but changes in elasticity following 1 week of treatment did. Medication group had no effect on any subjective effects of smoking. Bupropion had no significant effects on demand for cigarettes. The exponential demand equation, recently introduced in behavioral economics, proved amenable to human simulated demand and might be usefully employed in other pharmacotherapy studies as it provides a potentially useful measure of changes in the essential value of the drug as a reinforcer. Such changes may be useful in predicting the efficacy of medications designed to reduce drug consumption.

Pathological demand avoidance: exploring the behavioural profile.

PubMed

O'Nions, Elizabeth; Viding, Essi; Greven, Corina U; Ronald, Angelica; Happé, Francesca

2014-07-01

'Pathological Demand Avoidance' is a term increasingly used by practitioners in the United Kingdom. It was coined to describe a profile of obsessive resistance to everyday demands and requests, with a tendency to resort to 'socially manipulative' behaviour, including outrageous or embarrassing acts. Pathological demand avoidance is thought to share aspects of social impairment with autism spectrum disorders, but autism spectrum disorder-appropriate strategies, such as routine and repetition, are described as unhelpful. Outrageous acts and lack of concern for their effects draw parallels with conduct problems and callous-unemotional traits. However, reward-based techniques, effective with conduct problems and callous-unemotional traits, seem not to work in pathological demand avoidance. Despite increasing interest and controversy over the pathological demand avoidance label, there is only one published study to date. We present the first systematic comparison of the behavioural profile of children receiving the term pathological demand avoidance (N = 25) to children with autism spectrum disorders (N = 39) or conduct problems and callous-unemotional traits (N = 28), using parent-report indices of psychopathology. The pathological demand avoidance group displayed comparable levels of autistic traits and peer problems to the autism spectrum disorders group and anti-social traits approaching those seen in the conduct problems and callous-unemotional traits group. Emotional symptoms in pathological demand avoidance exceeded both comparison groups. Findings highlight the extreme behavioural impairment associated with pathological demand avoidance and the need to explore whether behavioural overlap reflects a similar neurocognitive basis to existing groups. © The Author(s) 2013.

Interrelationships between marijuana demand and discounting of delayed rewards: Convergence in behavioral economic methods.

PubMed

Aston, Elizabeth R; Metrik, Jane; Amlung, Michael; Kahler, Christopher W; MacKillop, James

2016-12-01

Distinct behavioral economic domains, including high perceived drug value (demand) and delay discounting (DD), have been implicated in the initiation of drug use and the progression to dependence. However, it is unclear whether frequent marijuana users conform to a "reinforcer pathology" addiction model wherein marijuana demand and DD jointly increase risk for problematic marijuana use and cannabis dependence (CD). Participants (n=88, 34% female, 14% cannabis dependent) completed a marijuana purchase task at baseline. A delay discounting task was completed following placebo marijuana cigarette (0% THC) administration during a separate experimental session. Marijuana demand and DD were quantified using area under the curve (AUC). In multiple regression models, demand uniquely predicted frequency of marijuana use while DD did not. In contrast, DD uniquely predicted CD symptom count while demand did not. There were no significant interactions between demand and DD in either model. These findings suggest that frequent marijuana users exhibit key constituents of the reinforcer pathology model: high marijuana demand and steep discounting of delayed rewards. However, demand and DD appear to be independent rather than synergistic risk factors for elevated marijuana use and risk for progression to CD. Findings also provide support for using AUC as a singular marijuana demand metric, particularly when also examining other behavioral economic constructs that apply similar statistical approaches, such as DD, to support analytic methodological convergence. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Modelling Per Capita Water Demand Change to Support System Planning

NASA Astrophysics Data System (ADS)

Garcia, M. E.; Islam, S.

2016-12-01

Water utilities have a number of levers to influence customer water usage. These include levers to proactively slow demand growth over time such as building and landscape codes as well as levers to decrease demands quickly in response to water stress including price increases, education campaigns, water restrictions, and incentive programs. Even actions aimed at short term reductions can result in long term water usage declines when substantial changes are made in water efficiency, as in incentives for fixture replacement or turf removal, or usage patterns such as permanent lawn watering restrictions. Demand change is therefore linked to hydrological conditions and to the effects of past management decisions - both typically included in water supply planning models. Yet, demand is typically incorporated exogenously using scenarios or endogenously using only price, though utilities also use rules and incentives issued in response to water stress and codes specifying standards for new construction to influence water usage. Explicitly including these policy levers in planning models enables concurrent testing of infrastructure and policy strategies and illuminates interactions between the two. The City of Las Vegas is used as a case study to develop and demonstrate this modeling approach. First, a statistical analysis of system data was employed to rule out alternate hypotheses of per capita demand decrease such as changes in population density and economic structure. Next, four demand sub-models were developed including one baseline model in which demand is a function of only price. The sub-models were then calibrated and tested using monthly data from 1997 to 2012. Finally, the best performing sub-model was integrated with a full supply and demand model. The results highlight the importance of both modeling water demand dynamics endogenously and taking a broader view of the variables influencing demand change.

Modeling the Trajectory of Analgesic Demand Over Time After Total Knee Arthroplasty Using the Latent Curve Analysis.

PubMed

Lo, Po-Han; Tsou, Mei-Yung; Chang, Kuang-Yi

2015-09-01

Patient-controlled epidural analgesia (PCEA) is commonly used for pain relief after total knee arthroplasty (TKA). This study aimed to model the trajectory of analgesic demand over time after TKA and explore its influential factors using latent curve analysis. Data were retrospectively collected from 916 patients receiving unilateral or bilateral TKA and postoperative PCEA. PCEA demands during 12-hour intervals for 48 hours were directly retrieved from infusion pumps. Potentially influential factors of PCEA demand, including age, height, weight, body mass index, sex, and infusion pump settings, were also collected. A latent curve analysis with 2 latent variables, the intercept (baseline) and slope (trend), was applied to model the changes in PCEA demand over time. The effects of influential factors on these 2 latent variables were estimated to examine how these factors interacted with time to alter the trajectory of PCEA demand over time. On average, the difference in analgesic demand between the first and second 12-hour intervals was only 15% of that between the first and third 12-hour intervals. No significant difference in PCEA demand was noted between the third and fourth 12-hour intervals. Aging tended to decrease the baseline PCEA demand but body mass index and infusion rate were positively correlated with the baseline. Only sex significantly affected the trend parameter and male individuals tended to have a smoother decreasing trend of analgesic demands over time. Patients receiving bilateral procedures did not consume more analgesics than their unilateral counterparts. Goodness of fit analysis indicated acceptable model fit to the observed data. Latent curve analysis provided valuable information about how analgesic demand after TKA changed over time and how patient characteristics affected its trajectory.

Two-and-a-half-year-olds succeed at a traditional false-belief task with reduced processing demands

PubMed Central

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

A rational approach to estimating the surgical demand elasticity needed to guide manpower reallocation during contagious outbreaks.

PubMed

Tsao, Hsiao-Mei; Sun, Ying-Chou; Liou, Der-Ming

2015-01-01

Emerging infectious diseases continue to pose serious threats to global public health. So far, however, few published study has addressed the need for manpower reallocation needed in hospitals when such a serious contagious outbreak occurs. To quantify the demand elasticity of the major surgery types in order to guide future manpower reallocation during contagious outbreaks. Based on a nationwide research database in Taiwan, we extracted the monthly volumes of major surgery types for the period 1998-2003, which covered the SARS period, in order to carry out a time series analysis. The demand elasticity of each surgery type was then estimated by autoregressive integrated moving average (ARIMA) analysis. During the study period, the surgical volumes of most selected surgery types either increased or remained steady. We categorized these surgery types into low-, moderate- and high-elastic groups according to their demand elasticity. Appendectomy, 'open reduction of fracture with internal fixation' and 'free skin graft' were in the low demand elasticity group. Transurethral prostatectomy and extracorporeal shockwave lithotripsy (ESWL) were in the high demand elasticity group. The manpower of the departments carrying out the surgeries with low demand elasticity should be maintained during outbreaks. In contrast, departments in charge of surgeries mainly with high demand elasticity, like urology departments, may be in a position to have part of their staff reallocated. Taking advantage of the demand variation during the SARS period in 2003, we adopted the concept of demand elasticity and used a time series approach to figure out an effective index of demand elasticity for various types of surgery that could be used as a rational reference to carry out manpower reallocation during contagious outbreak situations.

A Rational Approach to Estimating the Surgical Demand Elasticity Needed to Guide Manpower Reallocation during Contagious Outbreaks

PubMed Central

Tsao, Hsiao-Mei; Sun, Ying-Chou; Liou, Der-Ming

2015-01-01

Background Emerging infectious diseases continue to pose serious threats to global public health. So far, however, few published study has addressed the need for manpower reallocation needed in hospitals when such a serious contagious outbreak occurs. Aim To quantify the demand elasticity of the major surgery types in order to guide future manpower reallocation during contagious outbreaks. Materials and Methods Based on a nationwide research database in Taiwan, we extracted the monthly volumes of major surgery types for the period 1998–2003, which covered the SARS period, in order to carry out a time series analysis. The demand elasticity of each surgery type was then estimated by autoregressive integrated moving average (ARIMA) analysis. Results During the study period, the surgical volumes of most selected surgery types either increased or remained steady. We categorized these surgery types into low-, moderate- and high-elastic groups according to their demand elasticity. Appendectomy, ‘open reduction of fracture with internal fixation’ and ‘free skin graft’ were in the low demand elasticity group. Transurethral prostatectomy and extracorporeal shockwave lithotripsy (ESWL) were in the high demand elasticity group. The manpower of the departments carrying out the surgeries with low demand elasticity should be maintained during outbreaks. In contrast, departments in charge of surgeries mainly with high demand elasticity, like urology departments, may be in a position to have part of their staff reallocated. Conclusions Taking advantage of the demand variation during the SARS period in 2003, we adopted the concept of demand elasticity and used a time series approach to figure out an effective index of demand elasticity for various types of surgery that could be used as a rational reference to carry out manpower reallocation during contagious outbreak situations. PMID:25837596

Water stress as a trigger of demand change: exploring the implications for drought planning

NASA Astrophysics Data System (ADS)

Garcia, M. E.; Islam, S.; Portney, K. E.

2015-12-01

Drought in the Anthropocene is a function of both supply and demand. Despite its importance, demand is typically incorporated into planning models exogenously using a single scenario of demand change over time. Alternatively, demand is incorporated endogenously in hydro-economic models based on the assumption of rationality. However, actors are constrained by limited information and information processing capabilities, casting doubt on the rationality assumption. Though the risk of water shortage changes incrementally with demand growth and hydrologic change, significant shifts in management are punctuated and often linked to periods of stress. The observation of lasting decreases in per capita demands in a number of cities during periods of water stress prompts an alternate hypothesis: the occurrence of water stress increases the tendency of cities to promote and enforce efficient technologies and behaviors and the tendency of users to adopt them. We show the relevance of this hypothesis by building a model of a hypothetical surface water system to answer the following question: what is the impact of reservoir operation policy on the reliability of water supply for a growing city? The model links the rate of demand decreases to the past reliability to compare standard operating policy (SOP) with hedging policy (HP). Under SOP, demand is fulfilled unless available supply drops below demand; under HP, water releases are reduced in anticipation of a deficit to decrease the risk of a large shortfall. The model shows that reservoir storage acts both as a buffer for variability and as a delay triggering oscillations around a sustainable level of demand. HP reduces the threshold for action thereby decreasing the delay and the oscillation effect. As a result per capita demand decrease during periods of water stress are more frequent but less drastic and the additive effect of small adjustments decreases the tendency of the system to overshoot available supplies.

Use of demand for and spatial flow of ecosystem services to identify priority areas.

PubMed

Verhagen, Willem; Kukkala, Aija S; Moilanen, Atte; van Teeffelen, Astrid J A; Verburg, Peter H

2017-08-01

Policies and research increasingly focus on the protection of ecosystem services (ESs) through priority-area conservation. Priority areas for ESs should be identified based on ES capacity and ES demand and account for the connections between areas of ES capacity and demand (flow) resulting in areas of unique demand-supply connections (flow zones). We tested ways to account for ES demand and flow zones to identify priority areas in the European Union. We mapped the capacity and demand of a global (carbon sequestration), a regional (flood regulation), and 3 local ESs (air quality, pollination, and urban leisure). We used Zonation software to identify priority areas for ESs based on 6 tests: with and without accounting for ES demand and 4 tests that accounted for the effect of ES flow zone. There was only 37.1% overlap between the 25% of priority areas that encompassed the most ESs with and without accounting for ES demand. The level of ESs maintained in the priority areas increased from 23.2% to 57.9% after accounting for ES demand, especially for ESs with a small flow zone. Accounting for flow zone had a small effect on the location of priority areas and level of ESs maintained but resulted in fewer flow zones without ES maintained relative to ignoring flow zones. Accounting for demand and flow zones enhanced representation and distribution of ESs with local to regional flow zones without large trade-offs relative to the global ES. We found that ignoring ES demand led to the identification of priority areas in remote regions where benefits from ES capacity to society were small. Incorporating ESs in conservation planning should therefore always account for ES demand to identify an effective priority network for ESs. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

[Patterns and characteristics of ecological water demand in west arid zone of China--a case study of green corridor in the lower reaches of Tarim River].

PubMed

Wang, Ranghui; Lu, Xinming; Song, Yudong; Fan, Zili; Ma, Yingjie

2003-04-01

Ecological water demand has some characteristics. The ecological water demand that was used for protection of the green corridor in the lower reaches of Tarim River was chiefly water demand by natural vegetation below Daxihaizi reservoir, and it included gross restoration water amount of ground water level and gross stand water amount in all over the lower reaches of Tarim River. The gross restoration water amount of ground water level mainly included restoration water amount of ground water level and lateral discharge, as well as evaporation of the course. Based on the drainage target of Alagan in 2005, gross ecological water demand was the gross water amount of restoration ground water level between Daxihaizi and Alagan, which would be 13.20 x 10(8) m3. Meanwhile, the annual average water demand would be 2.64 x 10(8) m3. Because the drainage target and vegetation protection target would be all Taitema lake in 2010, the gross ecological water demand included not only the gross water amount of restoration ground water level between Alagan and Taitema lake, but also the ecological stand water amount between Daxihaizi and Taitema lake, which would be 18.32 x 10(8) m3. Meanwhile, the annual average water demand would be 3.66 x 10(8) m3. From the year 2010 to 2030, the gross ecological water demand would be consisted of two parts (the gross stand water amount between Daxihaizi and Alagan, and the water demand by increased vegetation of 18.67 x 10(4) hm2), and the total ecological water demand during the 20 years would be 139.00 x 10(8) m3. Meanwhile, the annual average water demand would be 6.95 x 10(8) m3.

Interpersonal interactions, job demands and work-related outcomes in pharmacy.

PubMed

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.

Voluntary medical male circumcision: a qualitative study exploring the challenges of costing demand creation in eastern and southern Africa.

PubMed

Bertrand, Jane T; Njeuhmeli, Emmanuel; Forsythe, Steven; Mattison, Sarah K; Mahler, Hally; Hankins, Catherine A

2011-01-01

This paper proposes an approach to estimating the costs of demand creation for voluntary medical male circumcision (VMMC) scale-up in 13 countries of eastern and southern Africa. It addresses two key questions: (1) what are the elements of a standardized package for demand creation? And (2) what challenges exist and must be taken into account in estimating the costs of demand creation? We conducted a key informant study on VMMC demand creation using purposive sampling to recruit seven people who provide technical assistance to government programs and manage budgets for VMMC demand creation. Key informants provided their views on the important elements of VMMC demand creation and the most effective funding allocations across different types of communication approaches (e.g., mass media, small media, outreach/mobilization). The key finding was the wide range of views, suggesting that a standard package of core demand creation elements would not be universally applicable. This underscored the importance of tailoring demand creation strategies and estimates to specific country contexts before estimating costs. The key informant interviews, supplemented by the researchers' field experience, identified these issues to be addressed in future costing exercises: variations in the cost of VMMC demand creation activities by country and program, decisions about the quality and comprehensiveness of programming, and lack of data on critical elements needed to "trigger the decision" among eligible men. Based on this study's findings, we propose a seven-step methodological approach to estimate the cost of VMMC scale-up in a priority country, based on our key assumptions. However, further work is needed to better understand core components of a demand creation package and how to cost them. Notwithstanding the methodological challenges, estimating the cost of demand creation remains an essential element in deriving estimates of the total costs for VMMC scale-up in eastern and southern Africa.

Voluntary Medical Male Circumcision: A Qualitative Study Exploring the Challenges of Costing Demand Creation in Eastern and Southern Africa

PubMed Central

Bertrand, Jane T.; Njeuhmeli, Emmanuel; Forsythe, Steven; Mattison, Sarah K.; Mahler, Hally; Hankins, Catherine A.

2011-01-01

Background This paper proposes an approach to estimating the costs of demand creation for voluntary medical male circumcision (VMMC) scale-up in 13 countries of eastern and southern Africa. It addresses two key questions: (1) what are the elements of a standardized package for demand creation? And (2) what challenges exist and must be taken into account in estimating the costs of demand creation? Methods and Findings We conducted a key informant study on VMMC demand creation using purposive sampling to recruit seven people who provide technical assistance to government programs and manage budgets for VMMC demand creation. Key informants provided their views on the important elements of VMMC demand creation and the most effective funding allocations across different types of communication approaches (e.g., mass media, small media, outreach/mobilization). The key finding was the wide range of views, suggesting that a standard package of core demand creation elements would not be universally applicable. This underscored the importance of tailoring demand creation strategies and estimates to specific country contexts before estimating costs. The key informant interviews, supplemented by the researchers' field experience, identified these issues to be addressed in future costing exercises: variations in the cost of VMMC demand creation activities by country and program, decisions about the quality and comprehensiveness of programming, and lack of data on critical elements needed to “trigger the decision” among eligible men. Conclusions Based on this study's findings, we propose a seven-step methodological approach to estimate the cost of VMMC scale-up in a priority country, based on our key assumptions. However, further work is needed to better understand core components of a demand creation package and how to cost them. Notwithstanding the methodological challenges, estimating the cost of demand creation remains an essential element in deriving estimates of the total costs for VMMC scale-up in eastern and southern Africa. PMID:22140450

Which resources moderate the effects of demanding work schedules on nurses working in residential elder care? A longitudinal study.

PubMed

Peters, Velibor; Houkes, Inge; de Rijk, Angelique E; Bohle, Philip L; Engels, Josephine A; Nijhuis, Frans J N

2016-06-01

Shiftwork is a major job demand for nurses and has been related to various negative consequences. Research suggests that personal and job resources moderate the impact of work schedules on stress, health and well-being. This longitudinal study examined whether the interactions of personal and job resources with work schedule demands predicted work engagement and emotional exhaustion in nursing. This longitudinal study included two waves of data collection with a one year follow-up using self-report questionnaires among 247 nurses working shifts or irregular working hours in residential care for the elderly in the Netherlands. Moderated structural equation modelling was conducted to examine the interactions between personal and job resources and work schedule demands. Two work schedule demands were assessed: type of work schedule (demanding vs. less demanding) and average weekly working hours. Two personal resources, active coping and healthy lifestyle, and two job resources, work schedule control and the work schedule fit with nurses' private life, were assessed. Results showed that the work schedule fit with nurses' private life buffered the relationship between work schedule demands and emotional exhaustion one year later. Furthermore, the work schedule fit with nurses' private life increased work engagement one year later when work schedule demands were high. Work schedule control strengthened the positive relationship between work schedule demands and emotional exhaustion one year later. The personal resources, active coping and healthy lifestyle were no moderators in this model. Nurses suffer less from decreasing work engagement and emotional exhaustion due to work schedule demands when their work schedules fit with their private lives. Work schedule control did not buffer, but strengthened the positive relationship between weekly working hours and emotional exhaustion one year later. Job resources appeared to be more important for nurses' well-being than personal resources. These findings highlight the importance of the fit of a work schedule with nurse's private life, if the work schedule is demanding. Copyright © 2016. Published by Elsevier Ltd.

Time of Day and Day of Week Trends in EMS Demand.

PubMed

Cantwell, Kate; Morgans, Amee; Smith, Karen; Livingston, Michael; Spelman, Tim; Dietze, Paul

2015-01-01

We examined temporal variations in overall Emergency Medical Services (EMS) demand, as well as medical and trauma cases separately. We analyzed cases according to time of day and day of week to determine whether population level demand demonstrates temporal patterns that will increase baseline knowledge for EMS planning. We conducted a secondary analysis of data from the Ambulance Victoria data warehouse covering the period 2008-2011. We included all cases of EMS attendance which resulted in 1,203,803 cases for review. Data elements comprised age, gender, date and time of call to the EMS emergency number along with the clinical condition of the patient. We employed Poisson regression to analyze case numbers and trigonometric regression to quantify distribution patterns. EMS demand exhibited a bimodal distribution with the highest peak at 10:00 and a second smaller peak at 19:00. The highest number of cases occurred on Fridays, and the lowest on Tuesdays and Wednesdays. However, the distribution of cases throughout the day differed by day of week. Distribution patterns on Fridays, Saturdays and Sundays differed significantly from the rest of the week (p < 0.001). When categorized into medical or trauma cases, medical cases were more frequent during working hours and involved patients of higher mean age (57 years vs. 49 years for trauma, p < 0.001). Trauma cases peaked on Friday and Saturday nights around midnight. Day of week EMS demand distribution patterns reveal differences that can be masked in aggregate data. Day of week EMS demand distribution patterns showed not only which days have differences in demand but the times of day at which the demand changes. Patterns differed by case type as well. These differences in distribution are important for EMS demand planning. Increased understanding of EMS demand patterns is imperative in a climate of ever-increasing demand and fiscal constraints. Further research is needed into the effect of age and case type on EMS demand.

Evaluating Outdoor Water Use Demand under Changing Climatic and Demographic Conditions: An Agent-based Modeling Approach

NASA Astrophysics Data System (ADS)

Kanta, L.

2016-12-01

Outdoor water use for landscape and irrigation constitutes a significant end use in residential water demand. In periods of water shortages, utilities may reduce garden demands by implementing irrigation system audits, rebate programs, local ordinances, and voluntary or mandatory water use restrictions. Because utilities do not typically record outdoor and indoor water uses separately, the effects of policies for reducing garden demands cannot be readily calculated. The volume of water required to meet garden demands depends on the housing density or lawn size, type of vegetation, climatic conditions, efficiency of garden irrigation systems, and consumer water-use behaviors. Many existing outdoor demand estimation methods are deterministic and do not include consumer responses to conservation campaigns. In addition, mandatory restrictions may have a substantial impact on reducing outdoor demands, but the effectiveness of mandatory restrictions depends on the timing and the frequency of restrictions, in addition to the distribution of housing density and consumer types within a community. This research investigates a garden end-use model by coupling an agent-based modeling approach and a mechanistic-stochastic water demand model to create a methodology for estimating garden demand and evaluating demand reduction policies. The garden demand model is developed for two water utilities, using a diverse data sets, including residential customer billing records, records of outdoor conservation programs, frequency and type of mandatory water use restrictions, lot size distribution, population growth, and climatic data. A set of garden irrigation parameter values, which are based on the efficiency of irrigation systems and irrigation habits of consumers, are determined for a set of conservation ordinances and restrictions. The model parameters are then validated using customer water usage data from the participating water utilities. A sensitivity analysis is conducted for garden irrigation parameters to determine the most significant factors that should be considered by water utilities to reduce outdoor demand. Data from multiple sources and the agent-based modeling methodology are integrated using a holistic approach to assist utilities in efficiently and sustainably managing outdoor demand.

Evaluating Outdoor Water Use Demand under Changing Climatic and Demographic Conditions: An Agent-based Modeling Approach

NASA Astrophysics Data System (ADS)

Kanta, L.; Berglund, E. Z.; Soh, M. H.

2017-12-01

Outdoor water-use for landscape and irrigation constitutes a significant end-use in total residential water demand. In periods of water shortages, utilities may reduce garden demands by implementing irrigation system audits, rebate programs, local ordinances, and voluntary or mandatory water-use restrictions. Because utilities do not typically record outdoor and indoor water-uses separately, the effects of policies for reducing garden demands cannot be readily calculated. The volume of water required to meet garden demands depends on the housing density, lawn size, type of vegetation, climatic conditions, efficiency of garden irrigation systems, and consumer water-use behaviors. Many existing outdoor demand estimation methods are deterministic and do not include consumer responses to conservation campaigns. In addition, mandatory restrictions may have a substantial impact on reducing outdoor demands, but the effectiveness of mandatory restrictions depends on the timing and the frequency of restrictions, in addition to the distribution of housing density and consumer types within a community. This research investigates a garden end-use model by coupling an agent-based modeling approach and a mechanistic-stochastic water demand model to create a methodology for estimating garden demand and evaluating demand reduction policies. The garden demand model is developed for two water utilities, using a diverse data sets, including residential customer billing records, outdoor conservation programs, frequency and type of mandatory water-use restrictions, lot size distribution, population growth, and climatic data. A set of garden irrigation parameter values, which are based on the efficiency of irrigation systems and irrigation habits of consumers, are determined for a set of conservation ordinances and restrictions. The model parameters are then validated using customer water usage data from the participating water utilities. A sensitivity analysis is conducted for garden irrigation parameters to determine the most significant factors that should be considered by water utilities to reduce outdoor demand. Data from multiple sources and the agent-based modeling methodology are integrated using a holistic approach to assist utilities in efficiently and sustainably managing outdoor demand.

Identifying water price and population criteria for meeting future urban water demand targets

NASA Astrophysics Data System (ADS)

Ashoori, Negin; Dzombak, David A.; Small, Mitchell J.

2017-12-01

Predictive models for urban water demand can help identify the set of factors that must be satisfied in order to meet future targets for water demand. Some of the explanatory variables used in such models, such as service area population and changing temperature and rainfall rates, are outside the immediate control of water planners and managers. Others, such as water pricing and the intensity of voluntary water conservation efforts, are subject to decisions and programs implemented by the water utility. In order to understand this relationship, a multiple regression model fit to 44 years of monthly demand data (1970-2014) for Los Angeles, California was applied to predict possible future demand through 2050 under alternative scenarios for the explanatory variables: population, price, voluntary conservation efforts, and temperature and precipitation outcomes predicted by four global climate models with two CO2 emission scenarios. Future residential water demand in Los Angeles is projected to be largely driven by price and population rather than climate change and conservation. A median projection for the year 2050 indicates that residential water demand in Los Angeles will increase by approximately 36 percent, to a level of 620 million m3 per year. The Monte Carlo simulations of the fitted model for water demand were then used to find the set of conditions in the future for which water demand is predicted to be above or below the Los Angeles Department of Water and Power 2035 goal to reduce residential water demand by 25%. Results indicate that increases in price can not ensure that the 2035 water demand target can be met when population increases. Los Angeles must rely on furthering their conservation initiatives and increasing their use of stormwater capture, recycled water, and expanding their groundwater storage. The forecasting approach developed in this study can be utilized by other cities to understand the future of water demand in water-stressed areas. Improving water demand forecasts will help planners understand and optimize future investments in water supply infrastructure and related programs.

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.

41 CFR 105-55.010 - Demand for payment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... demand letters are mailed or hand-delivered on the same day they are dated. For the purposes of written... Administration 55-COLLECTION OF CLAIMS OWED THE UNITED STATES § 105-55.010 Demand for payment. (a) Written demand... letters (usually no more than three, thirty days apart) will depend upon the type and amount of the debt...

Pulpwood supply and demand : development in the South, little growth elsewhere.

Treesearch

Peter J. Ince; Irene Durbak

2002-01-01

This long-range outlook derives from analysis of pulp and paper markets and pulpwood demands for wood panels. The analysis projects modest increases in pulpwood demand beyond 2010, with decelerating growth in paper and paperboard consumption; increased demand for pulpwood in wood panels; increased imports of pulp, paper, and paperboard; and little additional growth in...

Perceived Demands of Social Change and Depressive Symptoms in Adolescents from Different Educational Tracks

ERIC Educational Resources Information Center

Pinquart, Martin; Silbereisen, Rainer K.; Grümer, Sebastian

2014-01-01

We analyzed whether perceived demands associated with social change and coping with these demands are related to depressive symptoms in German adolescents from the highest versus middle/lowest educational track. Demands reflected an increase in uncertainty (e.g., risk for getting no job). Adolescents on the highest educational track perceived…

10 CFR 9.202 - Procedure in the event of a demand for production or disclosure.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Procedure in the event of a demand for production or disclosure. 9.202 Section 9.202 Energy NUCLEAR REGULATORY COMMISSION PUBLIC RECORDS Production or Disclosure... a demand for production or disclosure. (a) Prior to or simultaneous with a demand upon an employee...

24 CFR 15.203 - Making a demand for production of material or provision of testimony.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Making a demand for production of... INFORMATION ACT AND TESTIMONY AND PRODUCTION OF INFORMATION BY HUD EMPLOYEES Production of Material or... demand for production of material or provision of testimony. (a) Any demand made to the Department or an...

38 CFR 14.807 - Procedure when demand or request is made.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Production of Department Records in Legal Proceedings § 14.807 Procedure when demand or request is made. (a) VA personnel upon whom a demand or request for testimony or the production of records in connection...) In response to a demand or request for the production of records or the testimony of VA personnel...

36 CFR 703.17 - Procedures when testimony and/or documents are demanded.

Code of Federal Regulations, 2011 CFR

2011-07-01

.../or documents are demanded. 703.17 Section 703.17 Parks, Forests, and Public Property LIBRARY OF... Documents in Certain Legal Proceedings Where the Library Is Not a Party § 703.17 Procedures when testimony and/or documents are demanded. A demand for testimony and/or documents by a Library employee must be...

36 CFR 703.17 - Procedures when testimony and/or documents are demanded.

Code of Federal Regulations, 2014 CFR

2014-07-01

.../or documents are demanded. 703.17 Section 703.17 Parks, Forests, and Public Property LIBRARY OF... Documents in Certain Legal Proceedings Where the Library Is Not a Party § 703.17 Procedures when testimony and/or documents are demanded. A demand for testimony and/or documents by a Library employee must be...

36 CFR 703.17 - Procedures when testimony and/or documents are demanded.

Code of Federal Regulations, 2012 CFR

2012-07-01

.../or documents are demanded. 703.17 Section 703.17 Parks, Forests, and Public Property LIBRARY OF... Documents in Certain Legal Proceedings Where the Library Is Not a Party § 703.17 Procedures when testimony and/or documents are demanded. A demand for testimony and/or documents by a Library employee must be...

Toward a Conceptualization of Perceived Work-Family Fit and Balance: A Demands and Resources Approach

ERIC Educational Resources Information Center

Voydanoff, Patricia

2005-01-01

Using person-environment fit theory, this article formulates a conceptual model that links work, family, and boundary-spanning demands and resources to work and family role performance and quality. Linking mechanisms include 2 dimensions of perceived work-family fit (work demands--family resources fit and family demands--work resources fit) and a…

49 CFR 37.77 - Purchase or lease of new non-rail vehicles by public entities operating a demand responsive...

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...

49 CFR 37.77 - Purchase or lease of new non-rail vehicles by public entities operating a demand responsive...

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...

49 CFR 37.77 - Purchase or lease of new non-rail vehicles by public entities operating a demand responsive...

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...

49 CFR 37.77 - Purchase or lease of new non-rail vehicles by public entities operating a demand responsive...

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...

Demand Intensity, Market Parameters and Policy Responses towards Demand and Supply of Private Supplementary Tutoring in China

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…

5 CFR 1305.3 - Procedures in the event of a demand for disclosure.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Procedures in the event of a demand for disclosure. 1305.3 Section 1305.3 Administrative Personnel OFFICE OF MANAGEMENT AND BUDGET ADMINISTRATIVE....3 Procedures in the event of a demand for disclosure. (a) Whenever a demand is made upon an employee...

5 CFR 2502.32 - Procedure in the event of a demand for disclosure.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Procedure in the event of a demand for disclosure. 2502.32 Section 2502.32 Administrative Personnel OFFICE OF ADMINISTRATION, EXECUTIVE OFFICE OF... Other Authorities § 2502.32 Procedure in the event of a demand for disclosure. (a) Whenever a demand is...

5 CFR 1305.3 - Procedures in the event of a demand for disclosure.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Procedures in the event of a demand for disclosure. 1305.3 Section 1305.3 Administrative Personnel OFFICE OF MANAGEMENT AND BUDGET ADMINISTRATIVE....3 Procedures in the event of a demand for disclosure. (a) Whenever a demand is made upon an employee...

5 CFR 1631.32 - Procedure in the event of a demand for disclosure.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Procedure in the event of a demand for disclosure. 1631.32 Section 1631.32 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD... Procedure in the event of a demand for disclosure. (a) Whenever a demand is made upon an employee or former...

5 CFR 1631.32 - Procedure in the event of a demand for disclosure.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Procedure in the event of a demand for disclosure. 1631.32 Section 1631.32 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD... Procedure in the event of a demand for disclosure. (a) Whenever a demand is made upon an employee or former...

5 CFR 2502.32 - Procedure in the event of a demand for disclosure.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Procedure in the event of a demand for disclosure. 2502.32 Section 2502.32 Administrative Personnel OFFICE OF ADMINISTRATION, EXECUTIVE OFFICE OF... Other Authorities § 2502.32 Procedure in the event of a demand for disclosure. (a) Whenever a demand is...

5 CFR 1631.32 - Procedure in the event of a demand for disclosure.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Procedure in the event of a demand for disclosure. 1631.32 Section 1631.32 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD... Procedure in the event of a demand for disclosure. (a) Whenever a demand is made upon an employee or former...

5 CFR 1305.3 - Procedures in the event of a demand for disclosure.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Procedures in the event of a demand for disclosure. 1305.3 Section 1305.3 Administrative Personnel OFFICE OF MANAGEMENT AND BUDGET ADMINISTRATIVE....3 Procedures in the event of a demand for disclosure. (a) Whenever a demand is made upon an employee...

Changing Science Education to Meet the Demands of a Changing Society

ERIC Educational Resources Information Center

Fensham, Peter J.

2017-01-01

Changes in society can, on occasion, lead to new demands on schooling, and on science education in particular. A major such demand in the 1960s led to a conceptual form of science that has dominated school science education ever since. Subsequent major societal demands have usually not been nearly as successful in redefining school science…

Teacher Supply & Demand in Michigan and the United States 1994-95.

ERIC Educational Resources Information Center

Scheetz, L. Patrick; Gratz, Becky

This publication provides analysis of current data on the supply and demand for teachers nationally and in Michigan in 1994-95 along with tips for new teachers who are still seeking jobs. The text covers areas of education where demand is highest including special education and science education, notes the persistent demand for minority teachers…

24 CFR 2004.22 - Filing requirements for demands or requests for documents or testimony.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Filing requirements for demands or... AND URBAN DEVELOPMENT SUBPOENAS AND PRODUCTION IN RESPONSE TO SUBPOENAS OR DEMANDS OF COURTS OR OTHER AUTHORITIES Requests for Testimony and Production of Documents § 2004.22 Filing requirements for demands or...

24 CFR 2004.22 - Filing requirements for demands or requests for documents or testimony.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Filing requirements for demands or... AND URBAN DEVELOPMENT SUBPOENAS AND PRODUCTION IN RESPONSE TO SUBPOENAS OR DEMANDS OF COURTS OR OTHER AUTHORITIES Requests for Testimony and Production of Documents § 2004.22 Filing requirements for demands or...

36 CFR 1251.10 - What are the filing requirements for a demand for documents or testimony?

Code of Federal Regulations, 2011 CFR

2011-07-01

... date that records or testimony is required. Demands submitted in less than 45 days before records or... requirements for a demand for documents or testimony? 1251.10 Section 1251.10 Parks, Forests, and Public... the filing requirements for a demand for documents or testimony? You must comply with the following...

10 CFR 1707.203 - Filing requirements for demands or requests for documents or testimony.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 4 2011-01-01 2011-01-01 false Filing requirements for demands or requests for documents... Production of Documents § 1707.203 Filing requirements for demands or requests for documents or testimony. You must comply with the following requirements whenever you issue demands or requests to a DNFSB...

36 CFR 1251.10 - What are the filing requirements for a demand for documents or testimony?

Code of Federal Regulations, 2010 CFR

2010-07-01

... date that records or testimony is required. Demands submitted in less than 45 days before records or... requirements for a demand for documents or testimony? 1251.10 Section 1251.10 Parks, Forests, and Public... the filing requirements for a demand for documents or testimony? You must comply with the following...

Demand forecasting of electricity in Indonesia with limited historical data

NASA Astrophysics Data System (ADS)

Dwi Kartikasari, Mujiati; Rohmad Prayogi, Arif

2018-03-01

Demand forecasting of electricity is an important activity for electrical agents to know the description of electricity demand in future. Prediction of demand electricity can be done using time series models. In this paper, double moving average model, Holt’s exponential smoothing model, and grey model GM(1,1) are used to predict electricity demand in Indonesia under the condition of limited historical data. The result shows that grey model GM(1,1) has the smallest value of MAE (mean absolute error), MSE (mean squared error), and MAPE (mean absolute percentage error).

Estimating Demand for Alternatives to Cigarettes With Online Purchase Tasks

PubMed Central

O’Connor, Richard J.; June, Kristie M.; Bansal-Travers, Maansi; Rousu, Matthew C.; Thrasher, James F.; Hyland, Andrew; Cummings, K. Michael

2013-01-01

Objectives This study explored how advertising affects demand for cigarettes and potential substitutes, including snus, dissolvable tobacco, and medicinal nicotine. Methods A web-based experiment randomized 1062 smokers to see advertisements for alternative nicotine products or soft drinks, then complete a series of purchase tasks, which were used to estimate demand elasticity, peak consumption, and cross-price elasticity (CPE) for tobacco products. Results Lower demand elasticity and greater peak consumption were seen for cigarettes compared to all alternative products (p < .05). CPE did not differ across the alternative products (p ≤ .03). Seeing relevant advertisements was not significantly related to demand. Conclusions These findings suggest significantly lower demand for alternative nicotine sources among smokers than previously revealed. PMID:24034685

An Airline-Based Multilevel Analysis of Airfare Elasticity for Passenger Demand

NASA Technical Reports Server (NTRS)

Castelli, Lorenzo; Ukovich, Walter; Pesenti, Raffaele

2003-01-01

Price elasticity of passenger demand for a specific airline is estimated. The main drivers affecting passenger demand for air transportation are identified. First, an Ordinary Least Squares regression analysis is performed. Then, a multilevel analysis-based methodology to investigate the pattern of variation of price elasticity of demand among the various routes of the airline under study is proposed. The experienced daily passenger demands on each fare-class are grouped for each considered route. 9 routes were studied for the months of February and May in years from 1999 to 2002, and two fare-classes were defined (business and economy). The analysis has revealed that the airfare elasticity of passenger demand significantly varies among the different routes of the airline.

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

Some comments on the World Energy Conference (WEC) energy demand model

NASA Astrophysics Data System (ADS)

Brandell, L.

1982-04-01

The WEC model, relating the energy demand for a region in a year to gross national product (GNP), aggregated energy prices and elasticity constants, is generalized. The changes that result from the assumption that the elasticity factors are not constant are examined. The resulting differential equation contains the variables energy demand per capita and GNP per capita for the region considered. The effect of time lag in energy demand and the influence of the population growth rate are also included in the model. No projections of the future energy demand were made, but model sensitiveness to the modifications were studied. Time lag effects and population growth effects can raise the projected energy demand for a region by 10% or more.

U.S. Army physical demands study: Prevalence and frequency of performing physically demanding tasks in deployed and non-deployed settings.

PubMed

Boye, Michael W; Cohen, Bruce S; Sharp, Marilyn A; Canino, Maria C; Foulis, Stephen A; Larcom, Kathleen; Smith, Laurel

2017-11-01

To compare percentages of on-duty time spent performing physically demanding soldier tasks in non-deployed and deployed settings, and secondarily examine the number of physically demanding tasks performed among five Army combat arms occupational specialties. Job task analysis. Soldiers (n=1295; over 99% serving on active duty) across five Army jobs completed one of three questionnaires developed using reviews of job and task related documents, input from subject matter experts, observation of task performance, and conduct of focus groups. Soldiers reported estimates of the total on-duty time spent performing physically demanding tasks in both deployed and non-deployed settings. One-way analyses of variance and Duncan post-hoc tests were used to compare percentage time differences by job. Two-tailed t-tests were used to evaluate differences by setting. Frequency analyses were used to present supplementary findings. Soldiers reported performing physically demanding job-specific tasks 17.7% of the time while non-deployed and 19.6% of the time while deployed. There were significant differences in time spent on job-specific tasks across settings (p<0.05) for three of five occupational specialties. When categories of physically demanding tasks were grouped, all soldiers reported spending more time on physically demanding tasks when deployed (p<0.001). Twenty-five percent reported performing less than half the physically demanding tasks represented on the questionnaire in the last two years. Soldiers spent more time performing physically demanding tasks while deployed compared to non-deployed but spent similar amounts of time performing job-specific tasks. Published by Elsevier Ltd.

Age, occupational demands and the risk of serious work injury.

PubMed

Smith, P M; Berecki-Gisolf, J

2014-12-01

Interest in the relationship between age and serious work injury is increasing, given the ageing of the workforce in many industrialized economies. To examine if the relationship between age and risk of serious musculoskeletal injury differs when the physical demands of work are higher from those when they are lower. A secondary analysis of workers' compensation claims in the State of Victoria, Australia, combined with estimates of the insured labour force. We focused on musculoskeletal claims, which required 10 days of absence or health care expenditures beyond a pecuniary threshold. Regression models examined the relationship between age and claim-risk across workers with different occupational demands, as well as the relationship between occupational demands and musculoskeletal claim-risk across different age groups. Older age and greater physical demands at work were associated with an increased risk of musculoskeletal claims. In models stratified by occupational demands, we observed the relationship between age and claim-risk was steeper when occupational demands were higher. We also observed that the relationship between occupational demands and risk of work injury claim peaked among workers aged 25-44, attenuating among those aged 45 and older. This study's results suggest that although older workers and occupations with higher demands should be the targets of primary preventive efforts related to serious musculoskeletal injuries, there may also be gains in targeting middle-aged workers in the most physically demanding occupations. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Area under the curve as a novel metric of behavioral economic demand for alcohol.

PubMed

Amlung, Michael; Yurasek, Ali; McCarty, Kayleigh N; MacKillop, James; Murphy, James G

2015-06-01

Behavioral economic purchase tasks can be readily used to assess demand for a number of addictive substances, including alcohol, tobacco, and illicit drugs. However, several methodological limitations associated with the techniques used to quantify demand may reduce the utility of demand measures. In the present study, we sought to introduce area under the curve (AUC), commonly used to quantify degree of delay discounting, as a novel index of demand. A sample of 207 heavy-drinking college students completed a standard alcohol purchase task and provided information about typical weekly drinking patterns and alcohol-related problems. Level of alcohol demand was quantified using AUC--which reflects the entire amount of consumption across all drink prices--as well as the standard demand indices (e.g., intensity, breakpoint, Omax, Pmax, and elasticity). Results indicated that AUC was significantly correlated with each of the other demand indices (rs = .42-.92), with particularly strong associations with Omax (r = .92). In regression models, AUC and intensity were significant predictors of weekly drinking quantity, and AUC uniquely predicted alcohol-related problems, even after controlling for drinking level. In a parallel set of analyses, Omax also predicted drinking quantity and alcohol problems, although Omax was not a unique predictor of the latter. These results offer initial support for using AUC as an index of alcohol demand. Additional research is necessary to further validate this approach and to examine its utility in quantifying demand for other addictive substances such as tobacco and illicit drugs. (c) 2015 APA, all rights reserved).

Physical Demand but Not Dexterity Is Associated with Motor Flexibility during Rapid Reaching in Healthy Young Adults

PubMed Central

Greve, Christian; Hortobàgyi, Tibor; Bongers, Raoul M.

2015-01-01

Healthy humans are able to place light and heavy objects in small and large target locations with remarkable accuracy. Here we examine how dexterity demand and physical demand affect flexibility in joint coordination and end-effector kinematics when healthy young adults perform an upper extremity reaching task. We manipulated dexterity demand by changing target size and physical demand by increasing external resistance to reaching. Uncontrolled manifold analysis was used to decompose variability in joint coordination patterns into variability stabilizing the end-effector and variability de-stabilizing the end-effector during reaching. Our results demonstrate a proportional increase in stabilizing and de-stabilizing variability without a change in the ratio of the two variability components as physical demands increase. We interpret this finding in the context of previous studies showing that sensorimotor noise increases with increasing physical demands. We propose that the larger de-stabilizing variability as a function of physical demand originated from larger sensorimotor noise in the neuromuscular system. The larger stabilizing variability with larger physical demands is a strategy employed by the neuromuscular system to counter the de-stabilizing variability so that performance stability is maintained. Our findings have practical implications for improving the effectiveness of movement therapy in a wide range of patient groups, maintaining upper extremity function in old adults, and for maximizing athletic performance. PMID:25970465

Job demands, job resources, and work engagement of Japanese employees: a prospective cohort study.

PubMed

Inoue, Akiomi; Kawakami, Norito; Tsuno, Kanami; Shimazu, Akihito; Tomioka, Kimiko; Nakanishi, Mayuko

2013-05-01

Research on the prospective association of job demands and job resources with work engagement is still limited in Asian countries, such as Japan. The purpose of the present study was to investigate the prospective association of job demands (i.e., psychological demands and extrinsic effort) and job resources (i.e., decision latitude, supervisor support, co-worker support, and extrinsic reward), based on the job demands-control (JD-C) [or demand-control-support (DCS)] model and the effort-reward imbalance (ERI) model, with work engagement among Japanese employees. The participants included 423 males and 672 females from five branches of a manufacturing company in Japan. Self-administered questionnaires, including the Job Content Questionnaire (JCQ), the Effort-Reward Imbalance Questionnaire (ERIQ), the nine-item Utrecht Work Engagement Scale (UWES-9), and demographic characteristics, were administered at baseline (August 2009). At one-year follow-up (August 2010), the UWES-9 was used again to assess work engagement. Hierarchical multiple regression analyses were conducted. After adjusting for demographic characteristics and work engagement at baseline, higher psychological demands and decision latitude were positively and significantly associated with greater work engagement at follow-up (β = 0.054, p = 0.020 for psychological demands and β = 0.061, p = 0.020 for decision latitude). Having higher psychological demands and decision latitude may enhance work engagement among Japanese employees.

Alternative supply specifications and estimates of regional supply and demand for stumpage.

Treesearch

Kent P. Connaughton; David H. Jackson; Gerard A. Majerus

1988-01-01

Four plausible sets of stumpage supply and demand equations were developed and estimated; the demand equation was the same for each set, although the supply equation differed. The supply specifications varied from the model of regional excess demand in which National Forest harvest levels were assumed fixed to a more realistic model in which the harvest on the National...

Stress in Parents of Children with Autism Spectrum Disorder: An Exploration of Demands and Resources

ERIC Educational Resources Information Center

Krakovich, Teri M.; McGrew, John H.; Yu, Yue; Ruble, Lisa A.

2016-01-01

We applied the ABCX model of stress and coping to assess the association between child and family demands, school-based resources (i.e., parent-teacher alliance and COMPASS, a consultation intervention), and two measures of parent stress: perceptions of the demands of raising a child (Child domain) and reactions to those demands (Parent domain).…

The Impact of Labor Demand on Time to the Doctorate

ERIC Educational Resources Information Center

Groen, Jeffrey A.

2016-01-01

The goal of this paper is to estimate the impact of labor demand on time to the doctorate. Empirical investigation of this relationship in previous research was hampered by the difficulty of measuring labor demand. I construct a measure of labor demand in seven fields in the humanities and social sciences based on the annual number of job listings…

36 CFR § 703.17 - Procedures when testimony and/or documents are demanded.

Code of Federal Regulations, 2013 CFR

2013-07-01

.../or documents are demanded. § 703.17 Section § 703.17 Parks, Forests, and Public Property LIBRARY OF... Documents in Certain Legal Proceedings Where the Library Is Not a Party § 703.17 Procedures when testimony and/or documents are demanded. A demand for testimony and/or documents by a Library employee must be...

36 CFR 1251.2 - To what demands does this part apply?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false To what demands does this... PRODUCTION OF RECORDS IN LEGAL PROCEEDINGS § 1251.2 To what demands does this part apply? This part applies...) Demands upon or requests for a former NARA employee to testify as to matters in which the former employee...

The Role of Education in the Supply and Demand of Educated Manpower. Research Memorandum.

ERIC Educational Resources Information Center

Young, Kan Hua

This description of a methodology for examining the supply of educated manpower and the demand for their services consists of two major sections, which are devoted to the supply and demand of educated manpower respectively. In the first section, the supply of educated manpower and the demand for educational inputs are considered, the main…

Self-Efficacy and Workaholism as Initiators of the Job Demands-Resources Model

ERIC Educational Resources Information Center

Guglielmi, Dina; Simbula, Silvia; Schaufeli, Wilmar B.; Depolo, Marco

2012-01-01

Purpose: This study aims to investigate school principals' well-being by using the job demands-resources (JD-R) model as a theoretical framework. It aims at making a significant contribution to the development of this model by considering not only job demands and job resources, but also the role of personal resources and personal demands as…

The Job Demands-Resources Model: An Analysis of Additive and Joint Effects of Demands and Resources

ERIC Educational Resources Information Center

Hu, Qiao; Schaufeli, Wilmar B.; Taris, Toon W.

2011-01-01

The present study investigated the additive, synergistic, and moderating effects of job demands and job resources on well-being (burnout and work engagement) and organizational outcomes, as specified by the Job Demands-Resources (JD-R) model. A survey was conducted among two Chinese samples: 625 blue collar workers and 761 health professionals. A…

26 CFR 301.9000-2 - Considerations in responding to a request or demand for IRS records or information.

Code of Federal Regulations, 2010 CFR

2010-04-01

... demand for IRS records or information. 301.9000-2 Section 301.9000-2 Internal Revenue INTERNAL REVENUE... or demand for IRS records or information. (a) Situations in which disclosure shall not be authorized... requests or demands if testimony or disclosure of IRS records or information would— (1) Violate a Federal...

Coloring versus Drawing: Effects of Cognitive Demand on Mood Repair, Flow, and Enjoyment

ERIC Educational Resources Information Center

Forkosh, Jennifer; Drake, Jennifer E.

2017-01-01

We examined whether using drawing to distract, by either coloring a design or drawing a design, improves mood more than drawing to express feelings. We manipulated levels of cognitive demand in the first 2 conditions by asking participants to color a design (low cognitive demand) or draw a design (high cognitive demand). After a sad mood…

46 CFR 111.60-7 - Demand loads.

Code of Federal Regulations, 2010 CFR

2010-10-01

... REQUIREMENTS Wiring Materials and Methods § 111.60-7 Demand loads. Generator, feeder, and bus-tie cables must be selected on the basis of a computed load of not less than the demand load given in Table 111.60-7... 46 Shipping 4 2010-10-01 2010-10-01 false Demand loads. 111.60-7 Section 111.60-7 Shipping COAST...

46 CFR 111.60-7 - Demand loads.

Code of Federal Regulations, 2011 CFR

2011-10-01

... REQUIREMENTS Wiring Materials and Methods § 111.60-7 Demand loads. Generator, feeder, and bus-tie cables must be selected on the basis of a computed load of not less than the demand load given in Table 111.60-7... 46 Shipping 4 2011-10-01 2011-10-01 false Demand loads. 111.60-7 Section 111.60-7 Shipping COAST...

Opportunities for Energy Efficiency and Automated Demand Response in Industrial Refrigerated Warehouses in California

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

Social support moderates the impact of demands on burnout and organizational connectedness: a two-wave study of volunteer firefighters.

PubMed

Huynh, Jasmine Y; Xanthopoulou, Despoina; Winefield, Anthony H

2013-01-01

This two-wave study of volunteers examined the effect of family and friend support on the relationship between volunteer demands (emotional demands and work-home conflict) on the one hand, and burnout (exhaustion and cynicism) and organizational connectedness on the other hand. It was hypothesized that family and friend support would moderate the relationship between (a) demands at Time 1 (T1) and burnout at Time 2 (T2); and (b) demands at T1 and organizational connectedness at T2. Hypotheses were tested among 126 Australian volunteer firefighters, who were followed up over 1 year. Results showed that support moderated the relationship between work-home conflict and exhaustion, but not between emotional demands and exhaustion. In addition, family and friend support moderated the relationship between both volunteer demands at T1 and cynicism and organizational connectedness at T2. These results suggest that support from family and friends is a critical resource in coping with the demands related to volunteer work and may protect volunteers from burnout, while helping them to stay connected to volunteering. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

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.

Daily job demands and employee work engagement: The role of daily transformational leadership behavior.

PubMed

Breevaart, Kimberley; Bakker, Arnold B

2018-07-01

Using job demands-resources (JD-R) theory, the present study integrates the challenge stressor-hindrance stressor framework and leadership theory to investigate the relationship between daily transformational leadership behavior and employee work engagement. We hypothesized that daily transformational leadership behavior (a) sustains employee work engagement on days characterized by high challenge job demands, and (b) protects work engagement on days characterized by high hindrance job demands. Teachers filled out a short online questionnaire at the end of each workday during a 2-week period (N = 271 × 5.68 days = 1539). Results of latent moderated structural equation modeling showed that teachers' daily challenge demands (workload and cognitive demands) had a positive relationship with work engagement on the days transformational leadership was high (vs. low). In addition, teachers' daily hindrance demands (role-conflict, but not family to work conflict) had a negative relationship with work engagement on the days transformational leadership was low (vs. high). These findings show that the function of transformational leadership behavior changes from day to day, and depends on the type of job demand. We discuss the practical and theoretical implications of these findings. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Weather and age-gender effects on the projection of future emergency ambulance demand in Hong Kong.

PubMed

Lai, Poh-Chin; Wong, Ho-Ting

2015-03-01

An accurate projection for ambulance demand is essential to enable better resource planning for the future that strives to either maintain current levels of services or reconsider future standards and expectations. More than 2 million cases of emergency room attendance in 2008 were obtained from the Hong Kong Hospital Authority to project the demand for its ambulance services in 2036. The projection of ambulance demand in 2036 was computed in consideration of changes in the age-gender structure between 2008 and 2036. The quadratic relation between average daily temperature and daily ambulance demand in 2036 was further explored by including and excluding age-gender demographic changes. Without accounting for changes in the age-gender structure, the 2036 ambulance demand for age groups of 65 and above were consistently underestimated (by 38%-65%), whereas those of younger age groups were overestimated (by 6%-37%). Moreover, changes in the 2008 to 2036 age-gender structure also shift upward and emphasize relationships between average daily temperature and daily ambulance demand at both ends of the quadratic U-shaped curve. Our study reveals a potential societal implication of ageing population on the demand for ambulance services. © 2012 APJPH.

Job demand and cardiovascular disease risk factor in white-collar workers.

PubMed

Song, Young Kyu; Lee, Kang Koo; Kim, Hyoung Ryoul; Koo, Jung-Wan

2010-01-01

This study was conducted to determine whether job demand played a role as a risk factor of cardiovascular diseases by comparing changes of blood pressure, heart rate and rate pressure product (RPP) showing myocardial oxygen consumption (MVO2) according to levels of job demand. This cross-sectional study divided 177 male white-collar workers without a cardiovascular or metabolic disease according to their job demand and analyzed their body composition and results of graded exercise testing. There was no significant difference in height, body weight, body mass index (BMI), waist to hip ratio (WHR) and body fat percentage according to job demand. Maximal oxygen consumption (VO2max) and anaerobic threshold (AT) also did not show a significant difference. However, systolic blood pressures at the seventh and eighth stages over AT during exercise were significantly different and RPP was found to have a significant difference overall according to the job demand (p<0.05). These results meant that job demand affected systolic pressure in physical activities or at exercise intensity over AT and reduced energy efficiency of myocardium during physical activities. The results suggest that high job demand may be a risk factor of cardiovascular diseases.

The interplay of matching and non-matching job demands and resources on emotional exhaustion among teachers.

PubMed

Feuerhahn, Nicolas; Bellingrath, Silja; Kudielka, Brigitte M

2013-07-01

We investigated how matching and non-matching demands and resources are related to emotional exhaustion (EE) in teachers. Theoretically, we draw on the Demand-Induced Strain Compensation (DISC) model that proposes that demands, resources, and strains are multidimensional and comprise emotional, cognitive, and physical components. We first tested whether resources compensate aversive effects of demands. Second, as proposed by the triple-match principle, we tested whether interaction effects between job demands and resources are most likely if demands, resources, and outcomes relate to the same dimension. We retrieved data from 177 school teachers; a subsample was re-examined after a time lag of about 21 month (N = 56). Linear regression analyses reveal concurrent and longitudinal main and interaction effects of teacher-specific emotional and cognitive job demands and resources on EE. Results support the compensation principle and triple-match principle. Therefore, the DISC model seems to provide a valuable framework for the study of interaction effects in job stress research and, in particular, for interventions to reduce job strain in teachers. © 2013 The Authors. Applied Psychology: Health and Well-Being © 2013 The International Association of Applied Psychology.

Staying well and engaged when demands are high: the role of psychological detachment.

PubMed

Sonnentag, Sabine; Binnewies, Carmen; Mojza, Eva J

2010-09-01

The authors of this study examined the relation between job demands and psychological detachment from work during off-job time (i.e., mentally switching off) with psychological well-being and work engagement. They hypothesized that high job demands and low levels of psychological detachment predict poor well-being and low work engagement. They proposed that psychological detachment buffers the negative impact of high job demands on well-being and work engagement. A longitudinal study (12-month time lag) with 309 human service employees showed that high job demands predicted emotional exhaustion, psychosomatic complaints, and low work engagement over time. Psychological detachment from work during off-job time predicted emotional exhaustion and buffered the relation between job demands and an increase in psychosomatic complaints and between job demands and a decrease in work engagement. The findings of this study suggest that psychological detachment from work during off-job time is an important factor that helps to protect employee well-being and work engagement. Copyright 2010 APA, all rights reserved

Tissue oxygen demand in regulation of the behavior of the cells in the vasculature.

PubMed

Barvitenko, Nadezhda N; Aslam, Muhammad; Filosa, Jessica; Matteucci, Elena; Nikinmaa, Mikko; Pantaleo, Antonella; Saldanha, Carlota; Baskurt, Oguz K

2013-08-01

The control of arteriolar diameters in microvasculature has been in the focus of studies on mechanisms matching oxygen demand and supply at the tissue level. Functionally, important vascular elements include EC, VSMC, and RBC. Integration of these different cell types into functional units aimed at matching tissue oxygen supply with tissue oxygen demand is only achieved when all these cells can respond to the signals of tissue oxygen demand. Many vasoactive agents that serve as signals of tissue oxygen demand have their receptors on all these types of cells (VSMC, EC, and RBC) implying that there can be a coordinated regulation of their behavior by the tissue oxygen demand. Such functions of RBC as oxygen carrying by Hb, rheology, and release of vasoactive agents are considered. Several common extra- and intracellular signaling pathways that link tissue oxygen demand with control of VSMC contractility, EC permeability, and RBC functioning are discussed. © 2013 John Wiley & Sons Ltd.

The impact of job and family demands on partner's fatigue: A study of Japanese dual-earner parents.

PubMed

Watanabe, Mayumi; Shimazu, Akihito; Bakker, Arnold B; Demerouti, Evangelia; Shimada, Kyoko; Kawakami, Norito

2017-01-01

This study of Japanese dual-earner couples examined the impact of family and job demands on one's own and one's partner's fatigue as well as gender differences in these effects. A total of 2,502 parents (1,251 couples) were surveyed using a self-administered questionnaire. A crossover model was tested using structural equation modeling. The results of structural equation modeling analyses showed that both job and family demands independently exacerbated fatigue. There was an indirect effect of job and family demands on partner fatigue through one's own fatigue only from husbands to wives. An indirect effect of job demands on partner fatigue through partner's family demands was identified only from wives to husbands. Furthermore, there were gender differences in the crossover of fatigue. This study shows that job and family demands influence family circumstances. When considering means to reduce employees' fatigue, gender differences in the mechanism of fatigue need to be taken into account.

A supply chain contract with flexibility as a risk-sharing mechanism for demand forecasting

NASA Astrophysics Data System (ADS)

Kim, Whan-Seon

2013-06-01

Demand forecasting is one of the main causes of the bullwhip effect in a supply chain. As a countermeasure for demand uncertainty as well as a risk-sharing mechanism for demand forecasting in a supply chain, this article studies a bilateral contract with order quantity flexibility. Under the contract, the buyer places orders in advance for the predetermined horizons and makes minimum purchase commitments. The supplier, in return, provides the buyer with the flexibility to adjust the order quantities later, according to the most updated demand information. To conduct comparative simulations, four-echelon supply chain models, that employ the contracts and different forecasting techniques under dynamic market demands, are developed. The simulation outcomes show that demand fluctuation can be effectively absorbed by the contract scheme, which enables better inventory management and customer service. Furthermore, it has been verified that the contract scheme under study plays a role as an effective coordination mechanism in a decentralised supply chain.

An analysis of short haul air passenger demand, volume 2

NASA Technical Reports Server (NTRS)

Blumer, T. P.; Swan, W. M.

1978-01-01

Several demand models for short haul air travel are proposed and calibrated on pooled data. The models are designed to predict demand and analyze some of the motivating phenomena behind demand generation. In particular, an attempt is made to include the effects of competing modes and of alternate destinations. The results support three conclusions: (1) the auto mode is the air mode's major competitor; (2) trip time is an overriding factor in intermodal competition, with air fare at its present level appearing unimportant to the typical short haul air traveler; and (3) distance appears to underly several demand generating phenomena, and therefore, must be considered very carefully to any intercity demand model. It may be the cause of the wide range of fare elasticities reported by researchers over the past 15 years. A behavioral demand model is proposed and calibrated. It combines the travel generating effects of income and population, the effects of modal split, the sensitivity of travel to price and time, and the effect of alternative destinations satisfying the trip purpose.

The impact of product information and trials on demand for smokeless tobacco and cigarettes: Evidence from experimental auctions

PubMed Central

Rousu, Matthew C.; O'Connor, Richard; Thrasher, James F; June, Kristie; Bansal-Travers, Maansi; Pitcavage, James

2014-01-01

Introduction Epidemiological and toxicological evidence suggests lower risk of smokeless tobacco (ST) products compared to cigarettes. Less is known, however, about consumer perceptions and use of novel forms of ST, including snus and dissolvable tobacco. Methods In this study, we conducted in-person experimental auctions in Buffalo, NY, Columbia, SC, and Selinsgrove, PA with 571 smokers to test the impact of information and product trials on smokers’ preferences. Auctions were conducted between November 2010-November 2011. Results We found no evidence of an impact of product trials on demand in our auctions. Anti-ST information increased demand for cigarettes when presented alone, but when presented with Pro-ST information it decreased demand for cigarettes. It did not decrease demand for ST products. Anti-smoking information increased demand for ST products, but did not affect cigarette demand. Conclusions These findings suggest that credible and effective communications about tobacco harm reduction should reinforce the negative effects of smoking. PMID:24321456

A multivariate time series approach to modeling and forecasting demand in the emergency department.

PubMed

Jones, Spencer S; Evans, R Scott; Allen, Todd L; Thomas, Alun; Haug, Peter J; Welch, Shari J; Snow, Gregory L

2009-02-01

The goals of this investigation were to study the temporal relationships between the demands for key resources in the emergency department (ED) and the inpatient hospital, and to develop multivariate forecasting models. Hourly data were collected from three diverse hospitals for the year 2006. Descriptive analysis and model fitting were carried out using graphical and multivariate time series methods. Multivariate models were compared to a univariate benchmark model in terms of their ability to provide out-of-sample forecasts of ED census and the demands for diagnostic resources. Descriptive analyses revealed little temporal interaction between the demand for inpatient resources and the demand for ED resources at the facilities considered. Multivariate models provided more accurate forecasts of ED census and of the demands for diagnostic resources. Our results suggest that multivariate time series models can be used to reliably forecast ED patient census; however, forecasts of the demands for diagnostic resources were not sufficiently reliable to be useful in the clinical setting.

The impact of product information and trials on demand for smokeless tobacco and cigarettes: evidence from experimental auctions.

PubMed

Rousu, Matthew C; O'Connor, Richard J; Thrasher, James F; June, Kristie M; Bansal-Travers, Maansi; Pitcavage, James

2014-03-01

Epidemiological and toxicological evidence suggests lower risk of smokeless tobacco (ST) products compared to cigarettes. Less is known, however, about consumer perceptions and use of novel forms of ST, including snus and dissolvable tobacco. In this study, we conducted in-person experimental auctions in Buffalo, NY, Columbia, SC, and Selinsgrove, PA with 571 smokers to test the impact of information and product trials on smokers' preferences. Auctions were conducted between November 2010-November 2011. We found no evidence of an impact of product trials on demand in our auctions. Anti-ST information increased demand for cigarettes when presented alone, but when presented with pro-ST information it decreased demand for cigarettes. It did not decrease demand for ST products. Anti-smoking information increased demand for ST products, but did not affect cigarette demand. These findings suggest that credible and effective communications about tobacco harm reduction should reinforce the negative effects of smoking. Copyright © 2013 Elsevier Inc. All rights reserved.

Do job demands and job control affect problem-solving?

PubMed

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.

Learning and strain among newcomers: a three-wave study on the effects of job demands and job control.

PubMed

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.

Reducing Demand Charges and Onsite Generation Variability Using Behind-the-Meter Energy Storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattarai, Bishnu P.; Myers, Kurt S.; Bush, Jason W.

Electric utilities in the United States are increasingly employing demand charges and/or real-time pricing. This directive is bringing potential opportunities in deploying behindthe-meter energy storage (BMES) systems for various grid functionalities. This study quantifies techno-economic benefits of BMES in reducing demand charge and smoothing load/generation intermittencies, and determines how those benefits vary with onsite distributed photovoltaic. We proposed a two-stage control algorithm, whereby the first stage proactively determines costoptimal BMES configuration for reducing peak-demands and demand charges, and the second stage adaptively compensates intermittent generations and short load spikes that may otherwise increase the demand charges. The performance of themore » proposed algorithm is evaluated through a 24 hours time sweep simulation performed using data from smart microgrid testbed at Idaho National Laboratory (INL). The simulation results demonstrated that this research provides a simple but effective solution for peak shaving, demand charge reductions, and smoothing onsite PV variability.« less

Joint Real-Time Energy and Demand-Response Management using a Hybrid Coalitional-Noncooperative Game

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Fulin; Gu, Yi; Hao, Jun

In order to model the interactions among utility companies, building demands and renewable energy generators (REGs), a hybrid coalitional-noncooperative game framework has been proposed. We formulate a dynamic non-cooperative game to study the energy dispatch within multiple utility companies, while we take a coalitional perspective on REGs and buildings demands through a hedonic coalition formation game approach. In this case, building demands request different power supply from REGs, then the building demands can be organized into an ultimate coalition structure through a distributed hedonic shift algorithm. At the same time, utility companies can also obtain a stable power generation profile.more » In addition, the interactive progress among the utility companies and building demands which cannot be supplied by REGs is implemented by distributed game theoretic algorithms. Numerical results illustrate that the proposed hybrid coalitional-noncooperative game scheme reduces the cost of both building demands and utility companies compared with the initial scene.« less

Can price get the monkey off our back? A meta-analysis of illicit drug demand.

PubMed

Gallet, Craig A

2014-01-01

Because of the increased availability of price data over the past 15 years, several studies have estimated the demand for illicit drugs, providing 462 estimates of the price elasticity. Results from estimating several meta-regressions reveal that these price elasticity estimates are influenced by a number of study characteristics. For instance, the price elasticity differs across drugs, with its absolute value being smallest for marijuana, compared with cocaine and heroin. Furthermore, price elasticity estimates are sensitive to whether demand is modeled in the short-run or the long-run, measures of quantity and price, whether or not alcohol and other illicit drugs are included in the specification of demand, and the location of demand. However, a number of other factors, including the functional form of demand, several specification issues, the type of data and method used to estimate demand, and the quality of the publication outlet, have less influence on the price elasticity. Copyright © 2013 John Wiley & Sons, Ltd.

Demand for Self-Employed Health Insurance.

PubMed

Emamgholipour, Sara; Arab, Mohammad; Ebrahimzadeh, Javad

2016-10-01

Health insurance provides financial support for health care expenditures. There are two types of health insurance: compulsory and voluntary. Voluntary health insurance can be divided into two categories: self-employed and supplementary. In this study, the main factors that affect the demand for self-employed health insurance in Iran were determined. In this cross-sectional study, data were derived from the 2013 Household Income and Expenditure Survey from the Statistical Center of Iran. Then, a logistic regression model was designed to determine the factors influencing health insurance demand. The age, income, and education level of the head of the household directly correlated with the demand for self-employed health insurance. There was no significant relationship between the demand for health insurance and the gender or marital status of the head of the household. In addition, there were no significant relationships between occupation or house ownership and the demand for health insurance in rural households. To promote voluntary health insurance, it is helpful to identify effective factors that stimulate the health insurance demand.

Demand and capacity planning in the emergency department: how to do it.

PubMed

Higginson, I; Whyatt, J; Silvester, K

2011-02-01

Unless emergency departments have adequate capacity to meet demand, they will fail to meet clinical and performance standards and will be operating in the 'coping zone'. This carries risks both for staff and patients. As part of a quality improvement programme, the authors undertook an in-depth analysis of demand and capacity for an emergency department in the UK. The paper describes this rigorous approach to capacity planning, which draws on techniques from other industries. Proper capacity planning is vital, but is often poorly done. Planning using aggregated data will lead to inadequate capacity. Understanding demand, and particularly the variation in that demand, is critical to success. Analysis of emergency department demand and capacity is the first step towards effective workforce planning and process redesign.

Decision on risk-averse dual-channel supply chain under demand disruption

NASA Astrophysics Data System (ADS)

Yan, Bo; Jin, Zijie; Liu, Yanping; Yang, Jianbo

2018-02-01

We studied dual-channel supply chains using centralized and decentralized decision-making models. We also conducted a comparative analysis of the decisions before and after demand disruption. The study shows that the amount of change in decision-making is a linear function of the amount of demand disruption, and it is independent of the risk-averse coefficient. The optimal sales volume decision of the disturbing supply chain is related to market share and demand disruption in the decentralized decision-making model. The optimal decision is only influenced by demand disruption in the centralized decision-making model. The stability of the sales volume of the two models is related to market share and demand disruption. The optimal system production of the two models shows robustness, but their stable internals are different.

Dose and elasticity of demand for self-administered cocaine in rats.

PubMed

Kearns, David N; Silberberg, Alan

2016-04-01

The present experiment tested whether the elasticity of demand for self-administered cocaine in rats is dose-dependent. Subjects lever pressed for three different doses of intravenous cocaine - 0.11, 0.33, and 1.0 mg/kg/infusion - on a demand procedure where the number of lever presses required per infusion increased within a session. The main finding was that demand for the 0.11 mg/kg dose was more elastic than it was for the two larger doses. There was no difference in demand elasticity between the 0.33 and 1.0 mg/kg doses. These results parallel findings previously reported in monkeys. The present study also demonstrated that a within-session procedure can be used to generate reliable demand curves.

An integrated communications demand model

NASA Astrophysics Data System (ADS)

Doubleday, C. F.

1980-11-01

A computer model of communications demand is being developed to permit dynamic simulations of the long-term evolution of demand for communications media in the U.K. to be made under alternative assumptions about social, economic and technological trends in British Telecom's business environment. The context and objectives of the project and the potential uses of the model are reviewed, and four key concepts in the demand for communications media, around which the model is being structured are discussed: (1) the generation of communications demand; (2) substitution between media; (3) technological convergence; and (4) competition. Two outline perspectives on the model itself are given.

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.

Policy implications of the GRI baseline projection of US energy supply and demand to 2010, 1993

NASA Astrophysics Data System (ADS)

1993-01-01

The paper summarizes the 1993 edition of the Gas Research Institute (GRI) Baseline Projection of U.S. Energy Supply and Demand and presents the implications of the projections that are important for GRI research and development planning and the gas industry. The survey of supply and demand considerations is followed by a breakdown of energy demand by type of fuel, by consumption sector, and by service application. Gas supply and prices are analyzed in terms of two scenarios: a constrained energy demand scenario, and an optimistic scenario. Tables and charts accompany the summary.

Neural Mechanisms for Adaptive Learned Avoidance of Mental Effort.

PubMed

Mitsuto Nagase, Asako; Onoda, Keiichi; Clifford Foo, Jerome; Haji, Tomoki; Akaishi, Rei; Yamaguchi, Shuhei; Sakai, Katsuyuki; Morita, Kenji

2018-02-05

Humans tend to avoid mental effort. Previous studies have demonstrated this tendency using various demand-selection tasks; participants generally avoid options associated with higher cognitive demand. However, it remains unclear whether humans avoid mental effort adaptively in uncertain and non-stationary environments, and if so, what neural mechanisms underlie this learned avoidance and whether they remain the same irrespective of cognitive-demand types. We addressed these issues by developing novel demand-selection tasks where associations between choice options and cognitive-demand levels change over time, with two variations using mental arithmetic and spatial reasoning problems (29:4 and 18:2 males:females). Most participants showed avoidance, and their choices depended on the demand experienced on multiple preceding trials. We assumed that participants updated the expected cost of mental effort through experience, and fitted their choices by reinforcement learning models, comparing several possibilities. Model-based fMRI analyses revealed that activity in the dorsomedial and lateral frontal cortices was positively correlated with the trial-by-trial expected cost for the chosen option commonly across the different types of cognitive demand, and also revealed a trend of negative correlation in the ventromedial prefrontal cortex. We further identified correlates of cost-prediction-error at time of problem-presentation or answering the problem, the latter of which partially overlapped with or were proximal to the correlates of expected cost at time of choice-cue in the dorsomedial frontal cortex. These results suggest that humans adaptively learn to avoid mental effort, having neural mechanisms to represent expected cost and cost-prediction-error, and the same mechanisms operate for various types of cognitive demand. SIGNIFICANCE STATEMENT In daily life, humans encounter various cognitive demands, and tend to avoid high-demand options. However, it remains unclear whether humans avoid mental effort adaptively under dynamically changing environments, and if so, what are the underlying neural mechanisms and whether they operate irrespective of cognitive-demand types. To address these issues, we developed novel tasks, where participants could learn to avoid high-demand options under uncertain and non-stationary environments. Through model-based fMRI analyses, we found regions whose activity was correlated with the expected mental effort cost, or cost-prediction-error, regardless of demand-type, with overlap or adjacence in the dorsomedial frontal cortex. This finding contributes to clarifying the mechanisms for cognitive-demand avoidance, and provides empirical building blocks for the emerging computational theory of mental effort. Copyright © 2018 the authors.

Three essays in energy consumption: Time series analyses

NASA Astrophysics Data System (ADS)

Ahn, Hee Bai

1997-10-01

Firstly, this dissertation investigates that which demand specification is an appropriate model for long-run energy demand between the conventional demand specification and the limited demand specification. In order to determine the components of a stable long-run demand for different sectors of the energy industry, I perform cointegration tests by using the Johansen test procedure. First, I test the conventional demand specification including prices and income as components. Second, I test a limited demand specification only income as a component. The reason for performing these tests is that we can determine that which demand specification is a good long-run predictor of energy consumption between the two demand specifications by using the cointegration tests. Secondly, for the purpose of planning and forecasting energy demand in case of cointegrated system, long-run elasticities are of particular interest. To retrieve the optimal level of energy demand in case of price shock, we need long-run elasticities rather than short-run elasticities. The energy demand study provides valuable information to the energy policy makers who are concerned about the long-run impact of taxes and tariffs. A long-run price elasticity is a primary barometer of the substitution effect between energy and non-energy inputs and long-run income elasticity is an important factor since we can measure the energy demand growing slowly or fast than in the past depending on the magnitude of long-run elasticity. The one other problem in estimating the total energy demand is that there exists an aggregation bias stemming from the process of summation in four different energy types for the total aggregation prices and total aggregation energy consumption. In order to measure the aggregation bias between the Btu aggregation method and the Divisia Index method, i.e., which methodology has less aggregation bias in the long-run, I compare the two estimation results with calculated results estimated on a disaggregated basis. Thus, we can confirm whether or not the theoretically superior methodology has less aggregation bias in empirical estimation. Thirdly, I investigate the causal relationships between energy use and GDP. In order to detect causal relationships both in the long-run and in the short-run, the VECM (Vector Error Correction Model) can be used if there exists cointegration relationships among the variables. I detect the causal effects between energy use and GDP by estimating the VECM based on the multivariate production function including the labor and capital variables.

[Burnout and psychosocial risk factors in the career of flight attendants: Descriptive study of a population of Lebanese flight attendants].

PubMed

Richa, N; Zreik, H; Richa, S

2016-04-01

The aim of our study was to investigate the influence of demographic factors (gender and age), work related factors (the position and years of practice) and psychosocial risk factors (cognitive demands, demands to hide emotions, work-family conflict, offensive behaviors…) on the development of burnout among flight attendants, and the nature of psychosocial factors to which they are exposed. The sample was divided into two groups: 67 flight attendants and 67 persons in various jobs. Our sampling units were informed and consented to fill in two questionnaires: the Copenhagen burnout inventory (CBI) and the Copenhagen Psychosocial Questionnaire (COPSOQ II). The burnout syndrome affected both groups equally. It affected equally the women as well as men, whatever their age categories and their years of experience. The flight attendants occupying an intermediate position in the hierarchy had the highest score on the burnout syndrome. The psychosocial factors significantly found in flight attendants compared to the control group were: demands for hiding emotions, quantitative demands, emotional demands, temporal demands, lack of influence at work, of rewards, of possibility for development and variation of work, poor quality of leadership, exposure to sexual harassment, lack of social support from supervisors, colleagues, social community at work and work-family conflict. Four of them correlated positively with the development of burnout: quantitative demands, temporal demands, emotional demands and work-family conflict. Their expected work volume is very high (quantitative demands). They have to perform their tasks quickly in a limited time without forgetting the technical constraints (temporal demands). They have to work with an average of three hundred passengers besides colleagues and subordinates, which requires diligent control of the emotions promoted by the airline code of conduct based on repression of emotions (emotional demands). These demands affect the workers once they find themselves in their family environment and can have a negative effect on their private life (work-family conflict). However, the predictability seems to allow them to be aware of decisions and changes and protect them against burnout. The profession of flight attendants appears to be characterized by some psychosocial risk factors, some of which are positively correlated with burnout. Improved working conditions can prevent these risks and protect these employees from burnout. Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Projected electric power demands for the Potomac Electric Power Company

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, J.W.

1975-07-01

Included are chapters on the background of the Potomac Electric Power Company, forecasting future power demand, demand modeling, accuracy of market predictions, and total power system requirements. (DG)

Standardized Sample Preparation Using a Drop-on-Demand Printing Platform

DTIC Science & Technology

2013-05-07

successful and robust methodology for energetic sample preparation. Keywords: drop-on-demand; inkjet printing; sample preparation OPEN ACCESS...on a similar length scale. Recently, drop-on-demand inkjet printing technology has emerged as an effective approach to produce test materials to...which most of the material is concentrated along the edges, samples prepared using drop-on-demand inkjet technology demonstrate excellent uniform

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand classes; test requirements. 84.163 Section 84.163 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF...

Applying the Job Demands--Resources Model to the Work--Home Interface: A Study among Medical Residents and Their Partners

ERIC Educational Resources Information Center

Bakker, Arnold B.; ten Brummelhuis, Lieke L.; Prins, Jelle T.; van der Heijden, Frank M. M. A.

2011-01-01

Work-home interference (WHI) is a prevalent problem because most employees have substantial family responsibilities on top of their work demands. The present study hypothesized that high job demands in combination with low job resources contribute to WHI. The job demands-resources (JD-R) model was used as a theoretical framework. Using a sample of…

A MODEL FOR THE DEMAND FOR HIGHER EDUCATION IN THE UNITED STATES, 1919-64.

ERIC Educational Resources Information Center

CAMPBELL, ROBERT; SIEGEL, BARRY N.

STATISTICAL DEMAND ANALYSIS, WHICH EMPHASIZES THE INFLUENCE OF RELATIVE PRICES AND REAL INCOME UPON THE DEMAND FOR A COMMODITY, WAS USED TO DEVELOP A MODEL OF THE DEMAND FOR HIGHER EDUCATION. THE STUDY IS BASED ON THE FACT THAT COLLEGE ENROLLMENT REPRESENTS THE PURCHASE OF BOTH A PRODUCER AND CONSUMER DURABLE, AND IS AN ACT OF INVESTMENT.…

Analysis and Strategies of the Unbalance of the Supply and Demand in the Higher Education Market of China

ERIC Educational Resources Information Center

Ma, Jie

2010-01-01

The popularization of higher education largely impacts the balance of the supply and demand of the China higher education market. Starting from the basic concepts of the supply and demand of higher education, the actuality and influencing factors of the supply and demand in China higher education market are analyzed in this article, and…

The Adoption of On-Demand Learning in Organizations in the United States

ERIC Educational Resources Information Center

Cui, Lianbin

2010-01-01

There is a lack of studies on the current status of the use of on-demand learning in organizations and factors that may accelerate or hold back the acceptance and implementation of on-demand learning in organizations. The purpose of this study is to contribute to a better understanding of the adoption of on-demand learning in organizations in the…

The Effect of the Demand Control and Effort Reward Imbalance Models on the Academic Burnout of Korean Adolescents

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…

17 CFR 240.15c3-1d - Satisfactory Subordination Agreements (Appendix D to 17 CFR 240.15c3-1).

Code of Federal Regulations, 2011 CFR

2011-04-01

... less than the unpaid principal amount of the secured demand note. (E) Upon payment by the lender, as... any securities, then pledged as collateral to secure the secured demand note is less than the unpaid... secured demand note, up to an amount not less than the unpaid principal amount of the secured demand note...

Climate change and peak demand for electricity: Evaluating policies for reducing peak demand under different climate change scenarios

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.

Projected Demand and Potential Impacts to the National Airspace System of Autonomous, Electric, On-Demand Small Aircraft

NASA Technical Reports Server (NTRS)

Smith, Jeremy C.; Viken, Jeffrey K.; Guerreiro, Nelson M.; Dollyhigh, Samuel M.; Fenbert, James W.; Hartman, Christopher L.; Kwa, Teck-Seng; Moore, Mark D.

2012-01-01

Electric propulsion and autonomy are technology frontiers that offer tremendous potential to achieve low operating costs for small-aircraft. Such technologies enable simple and safe to operate vehicles that could dramatically improve regional transportation accessibility and speed through point-to-point operations. This analysis develops an understanding of the potential traffic volume and National Airspace System (NAS) capacity for small on-demand aircraft operations. Future demand projections use the Transportation Systems Analysis Model (TSAM), a tool suite developed by NASA and the Transportation Laboratory of Virginia Polytechnic Institute. Demand projections from TSAM contain the mode of travel, number of trips and geographic distribution of trips. For this study, the mode of travel can be commercial aircraft, automobile and on-demand aircraft. NASA's Airspace Concept Evaluation System (ACES) is used to assess NAS impact. This simulation takes a schedule that includes all flights: commercial passenger and cargo; conventional General Aviation and on-demand small aircraft, and operates them in the simulated NAS. The results of this analysis projects very large trip numbers for an on-demand air transportation system competitive with automobiles in cost per passenger mile. The significance is this type of air transportation can enhance mobility for communities that currently lack access to commercial air transportation. Another significant finding is that the large numbers of operations can have an impact on the current NAS infrastructure used by commercial airlines and cargo operators, even if on-demand traffic does not use the 28 airports in the Continental U.S. designated as large hubs by the FAA. Some smaller airports will experience greater demand than their current capacity allows and will require upgrading. In addition, in future years as demand grows and vehicle performance improves other non-conventional facilities such as short runways incorporated into shopping mall or transportation hub parking areas could provide additional capacity and convenience.

Do school classrooms meet the visual requirements of children and recommended vision standards?

PubMed

Negiloni, Kalpa; Ramani, Krishna Kumar; Sudhir, Rachapalle Reddi

2017-01-01

Visual demands of school children tend to vary with diverse classroom environments. The study aimed to evaluate the distance and near Visual Acuity (VA) demand in Indian school classrooms and their comparison with the recommended vision standards. The distance and near VA demands were assessed in 33 classrooms (grades 4 to 12) of eight schools. The VA threshold demand relied on the smallest size of distance and near visual task material and viewing distance. The logMAR equivalents of minimum VA demand at specific seating positions (desk) and among different grades were evaluated. The near threshold was converted into actual near VA demand by including the acuity reserve. The existing dimensions of chalkboard and classroom, gross area in a classroom per student and class size in all the measured classrooms were compared to the government recommended standards. In 33 classrooms assessed (35±10 students per room), the average distance and near logMAR VA threshold demand was 0.31±0.17 and 0.44±0.14 respectively. The mean distance VA demand (minimum) in front desk position was 0.56±0.18 logMAR. Increased distance threshold demand (logMAR range -0.06, 0.19) was noted in 7 classrooms (21%). The mean VA demand in grades 4 to 8 and grades 9 to 12 was 0.35±0.16 and 0.24±0.16 logMAR respectively and the difference was not statistically significant (p = 0.055). The distance from board to front desk was greater than the recommended standard of 2.2m in 27 classrooms (82%). The other measured parameters were noted to be different from the proposed standards in majority of the classrooms. The study suggests the inclusion of task demand assessment in school vision screening protocol to provide relevant guidance to school authorities. These findings can serve as evidence to accommodate children with mild to moderate visual impairment in the regular classrooms.

Estimating Oxygen Needs for Childhood Pneumonia in Developing Country Health Systems: A New Model for Expecting the Unexpected

PubMed Central

Bradley, Beverly D.; Howie, Stephen R. C.; Chan, Timothy C. Y.; Cheng, Yu-Ling

2014-01-01

Background Planning for the reliable and cost-effective supply of a health service commodity such as medical oxygen requires an understanding of the dynamic need or ‘demand’ for the commodity over time. In developing country health systems, however, collecting longitudinal clinical data for forecasting purposes is very difficult. Furthermore, approaches to estimating demand for supplies based on annual averages can underestimate demand some of the time by missing temporal variability. Methods A discrete event simulation model was developed to estimate variable demand for a health service commodity using the important example of medical oxygen for childhood pneumonia. The model is based on five key factors affecting oxygen demand: annual pneumonia admission rate, hypoxaemia prevalence, degree of seasonality, treatment duration, and oxygen flow rate. These parameters were varied over a wide range of values to generate simulation results for different settings. Total oxygen volume, peak patient load, and hours spent above average-based demand estimates were computed for both low and high seasons. Findings Oxygen demand estimates based on annual average values of demand factors can often severely underestimate actual demand. For scenarios with high hypoxaemia prevalence and degree of seasonality, demand can exceed average levels up to 68% of the time. Even for typical scenarios, demand may exceed three times the average level for several hours per day. Peak patient load is sensitive to hypoxaemia prevalence, whereas time spent at such peak loads is strongly influenced by degree of seasonality. Conclusion A theoretical study is presented whereby a simulation approach to estimating oxygen demand is used to better capture temporal variability compared to standard average-based approaches. This approach provides better grounds for health service planning, including decision-making around technologies for oxygen delivery. Beyond oxygen, this approach is widely applicable to other areas of resource and technology planning in developing country health systems. PMID:24587089

Pupillary Response to Cognitive Demand in Parkinson’s Disease: A Pilot Study

PubMed Central

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

The impact of monsoon intraseasonal variability on renewable power generation in India

NASA Astrophysics Data System (ADS)

Dunning, C. M.; Turner, A. G.; Brayshaw, D. J.

2015-06-01

India is increasingly investing in renewable technology to meet rising energy demands, with hydropower and other renewables comprising one-third of current installed capacity. Installed wind-power is projected to increase 5-fold by 2035 (to nearly 100GW) under the International Energy Agency's New Policies scenario. However, renewable electricity generation is dependent upon the prevailing meteorology, which is strongly influenced by monsoon variability. Prosperity and widespread electrification are increasing the demand for air conditioning, especially during the warm summer. This study uses multi-decadal observations and meteorological reanalysis data to assess the impact of intraseasonal monsoon variability on the balance of electricity supply from wind-power and temperature-related demand in India. Active monsoon phases are characterized by vigorous convection and heavy rainfall over central India. This results in lower temperatures giving lower cooling energy demand, while strong westerly winds yield high wind-power output. In contrast, monsoon breaks are characterized by suppressed precipitation, with higher temperatures and hence greater demand for cooling, and lower wind-power output across much of India. The opposing relationship between wind-power supply and cooling demand during active phases (low demand, high supply) and breaks (high demand, low supply) suggests that monsoon variability will tend to exacerbate fluctuations in the so-called demand-net-wind (i.e., electrical demand that must be supplied from non-wind sources). This study may have important implications for the design of power systems and for investment decisions in conventional schedulable generation facilities (such as coal and gas) that are used to maintain the supply/demand balance. In particular, if it is assumed (as is common) that the generated wind-power operates as a price-taker (i.e., wind farm operators always wish to sell their power, irrespective of price) then investors in conventional facilities will face additional weather-volatility through the monsoonal impact on the length and frequency of production periods (i.e. their load-duration curves).

Modeling and managing urban water demand through smart meters: Benefits and challenges from current research and emerging trends

NASA Astrophysics Data System (ADS)

Cominola, A.; Giuliani, M.; Castelletti, A.; Piga, D.; Rizzoli, A. E.

2015-12-01

Urban population growth, climate and land use change are expected to boost residential water demand in urban contexts in the next decades. In such a context, developing suitable demand-side management strategies is essential to meet future water demands, pursue water savings, and reduce the costs for water utilities. Yet, the effectiveness of water demand management strategies (WDMS) relies on our understanding of water consumers' behavior, their consumption habits, and the water use drivers. While low spatial and temporal resolution water consumption data, as traditionally gathered for billing purposes, hardly support this understanding, the advent of high-resolution, smart metering technologies allowed for quasi real-time monitoring water consumption at the single household level. This, in turn, is advancing our ability in characterizing consumers' behavior, modeling, and designing user-oriented residential water demand management strategies. Several water smart metering programs have been rolled-out in the last two decades worldwide, addressing one or more of the following water demand management phases: (i) data gathering, (ii) water end-uses characterization, (iii) user modeling, (iv) design and implementation of personalized WDMS. Moreover, the number of research studies in this domain is quickly increasing and big economic investments are currently being devoted worldwide to smart metering programs. With this work, we contribute the first comprehensive review of more than 100 experiences in the field of residential water demand modeling and management, and we propose a general framework for their classification. We revise consolidated practices, identify emerging trends and highlight the challenges and opportunities for future developments given by the use of smart meters advancing residential water demand management. Our analysis of the status quo of smart urban water demand management research and market constitutes a structured collection of information supporting the development of integrated procedures in the field of urban water management, as well as common actions aiding the collaboration with other sectors, as the nexus with energy demand management.

Combination of budesonide/formoterol on demand improves asthma control by reducing exercise-induced bronchoconstriction

PubMed Central

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

Unmanned Aircraft Systems Demand Forecast Study

NASA Technical Reports Server (NTRS)

Hackenberg, Davis L.

2017-01-01

UAS demand slides discuss the purpose, scope, and assumptions of the UAS Demand Forecast Study. It discusses some operational environments and market research study, this information is broad knowledge in the UAS community.

Quantifying and Mapping the Supply of and Demand for Carbon Storage and Sequestration Service from Urban Trees.

PubMed

Zhao, Chang; Sander, Heather A

2015-01-01

Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration.

Modification Effects of Changes in Job Demands on Associations Between Changes in Testosterone Levels and Andropause Symptoms: 2-Year Follow-up Study in Male Middle-Aged Japanese Workers.

PubMed

Hirokawa, Kumi; Taniguchi, Toshiyo; Fujii, Yasuhito; Takaki, Jiro; Tsutsumi, Akizumi

2016-08-01

The purpose of this longitudinal study was to ascertain if changes in job demands modify associations between changes in testosterone levels and andropause symptoms in male Japanese workers. A baseline survey including job demands and the Aging Males' Symptoms scale, lifestyle factors, and blood levels of testosterone was conducted in 2007. Among 192 men (mean age ± SD 52.2 ± 7.6 years) who completed all relevant questionnaires and provided blood at baseline, 104 men (50.9 ± 7.2 years) were followed up in 2009. Changes of variables in 2 years were calculated (data of follow-up minus those of baseline). Testosterone levels were increased significantly, whereas job demands and somatic symptoms were reduced significantly, at follow-up. Changes in testosterone levels were negatively associated with changes in total andropause symptoms, psychological symptoms, and sexual symptoms (standardized β = -0.27, -0.24, and, -0.29, p < 0.05, respectively), after adjustment for confounders. Changes in job demands were positively associated with changes in somatic symptoms (standardized β = 0.21, p < 0.05). Significant interactions of changes in testosterone levels and job demands were noted for changes in psychological symptoms (standardized β = 0.26, p < 0.05). For men with a 1-SD reduction in job demands, negative associations between changes in testosterone levels and psychological symptoms were intensified, but not for men with a 1-SD increase in job demands. Andropause symptoms may be affected by changes in testosterone levels and job demands. Change in job demands may modify associations between changes in testosterone levels and andropause symptoms.

Toward a better understanding of task demands, workload, and performance during physician-computer interactions.

PubMed

Mazur, Lukasz M; Mosaly, Prithima R; Moore, Carlton; Comitz, Elizabeth; Yu, Fei; Falchook, Aaron D; Eblan, Michael J; Hoyle, Lesley M; Tracton, Gregg; Chera, Bhishamjit S; Marks, Lawrence B

2016-11-01

To assess the relationship between (1) task demands and workload, (2) task demands and performance, and (3) workload and performance, all during physician-computer interactions in a simulated environment. Two experiments were performed in 2 different electronic medical record (EMR) environments: WebCIS (n = 12) and Epic (n = 17). Each participant was instructed to complete a set of prespecified tasks on 3 routine clinical EMR-based scenarios: urinary tract infection (UTI), pneumonia (PN), and heart failure (HF). Task demands were quantified using behavioral responses (click and time analysis). At the end of each scenario, subjective workload was measured using the NASA-Task-Load Index (NASA-TLX). Physiological workload was measured using pupillary dilation and electroencephalography (EEG) data collected throughout the scenarios. Performance was quantified based on the maximum severity of omission errors. Data analysis indicated that the PN and HF scenarios were significantly more demanding than the UTI scenario for participants using WebCIS (P < .01), and that the PN scenario was significantly more demanding than the UTI and HF scenarios for participants using Epic (P < .01). In both experiments, the regression analysis indicated a significant relationship only between task demands and performance (P < .01). Results suggest that task demands as experienced by participants are related to participants' performance. Future work may support the notion that task demands could be used as a quality metric that is likely representative of performance, and perhaps patient outcomes. The present study is a reasonable next step in a systematic assessment of how task demands and workload are related to performance in EMR-evolving environments. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Accommodation in Astigmatic Children During Visual Task Performance

PubMed Central

Harvey, Erin M.; Miller, Joseph M.; Apple, Howard P.; Parashar, Pavan; Twelker, J. Daniel; Crescioni, Mabel; Davis, Amy L.; Leonard-Green, Tina K.; Campus, Irene; Sherrill, Duane L.

2014-01-01

Purpose. To determine the accuracy and stability of accommodation in uncorrected children during visual task performance. Methods. Subjects were second- to seventh-grade children from a highly astigmatic population. Measurements of noncycloplegic right eye spherical equivalent (Mnc) were obtained while uncorrected subjects performed three visual tasks at near (40 cm) and distance (2 m). Tasks included reading sentences with stimulus letter size near acuity threshold and an age-appropriate letter size (high task demands) and viewing a video (low task demand). Repeated measures ANOVA assessed the influence of astigmatism, task demand, and accommodative demand on accuracy (mean Mnc) and variability (mean SD of Mnc) of accommodation. Results. For near and distance analyses, respectively, sample size was 321 and 247, mean age was 10.37 (SD 1.77) and 10.30 (SD 1.74) years, mean cycloplegic M was 0.48 (SD 1.10) and 0.79 diopters (D) (SD 1.00), and mean astigmatism was 0.99 (SD 1.15) and 0.75 D (SD 0.96). Poor accommodative accuracy was associated with high astigmatism, low task demand (video viewing), and high accommodative demand. The negative effect of accommodative demand on accuracy increased with increasing astigmatism, with the poorest accommodative accuracy observed in high astigmats (≥3.00 D) with high accommodative demand/high hyperopia (1.53 D and 2.05 D of underaccommodation for near and distant stimuli, respectively). Accommodative variability was greatest in high astigmats and was uniformly high across task condition. No/low and moderate astigmats showed higher variability for the video task than the reading tasks. Conclusions. Accuracy of accommodation is reduced in uncorrected children with high astigmatism and high accommodative demand/high hyperopia, but improves with increased visual task demand (reading). High astigmats showed the greatest variability in accommodation. PMID:25103265

Assessing the ability of potential evapotranspiration models in capturing dynamics of evaporative demand across various biomes and climatic regimes with ChinaFLUX measurements

NASA Astrophysics Data System (ADS)

Zheng, Han; Yu, Guirui; Wang, Qiufeng; Zhu, Xianjin; Yan, Junhua; Wang, Huimin; Shi, Peili; Zhao, Fenghua; Li, Yingnian; Zhao, Liang; Zhang, Junhui; Wang, Yanfen

2017-08-01

Estimates of atmospheric evaporative demand have been widely required for a variety of hydrological analyses, with potential evapotranspiration (PET) being an important measure representing evaporative demand of actual vegetated surfaces under given metrological conditions. In this study, we assessed the ability of various PET models in capturing long-term (typically 2003-2011) dynamics of evaporative demand at eight ecosystems across various biomes and climatic regimes in China. Prior to assessing PET dynamics, we first examined the reasonability of fourteen PET models in representing the magnitudes of evaporative demand using eddy-covariance actual evapotranspiration (AET) as an indicator. Results showed that the robustness of the fourteen PET models differed somewhat across the sites, and only three PET models could produce reasonable magnitudes of evaporative demand (i.e., PET ≥ AET on average) for all eight sites, including the: (i) Penman; (ii) Priestly-Taylor and (iii) Linacre models. Then, we assessed the ability of these three PET models in capturing dynamics of evaporative demand by comparing the annual and seasonal trends in PET against the equivalent trends in AET and precipitation (P) for particular sites. Results indicated that nearly all the three PET models could faithfully reproduce the dynamics in evaporative demand for the energy-limited conditions at both annual and seasonal scales, while only the Penman and Linacre models could represent dynamics in evaporative demand for the water-limited conditions. However, the Linacre model was unable to reproduce the seasonal switches between water- and energy-limited states for some sites. Our findings demonstrated that the choice of PET models would be essential for the evaporative demand analyses and other related hydrological analyses at different temporal and spatial scales.

Regional Renewable Energy Cooperatives

NASA Astrophysics Data System (ADS)

Hazendonk, P.; Brown, M. B.; Byrne, J. M.; Harrison, T.; Mueller, R.; Peacock, K.; Usher, J.; Yalamova, R.; Kroebel, R.; Larsen, J.; McNaughton, R.

2014-12-01

We are building a multidisciplinary research program linking researchers in agriculture, business, earth science, engineering, humanities and social science. Our goal is to match renewable energy supply and reformed energy demands. The program will be focused on (i) understanding and modifying energy demand, (ii) design and implementation of diverse renewable energy networks. Geomatics technology will be used to map existing energy and waste flows on a neighbourhood, municipal, and regional level. Optimal sites and combinations of sites for solar and wind electrical generation (ridges, rooftops, valley walls) will be identified. Geomatics based site and grid analyses will identify best locations for energy production based on efficient production and connectivity to regional grids and transportation. Design of networks for utilization of waste streams of heat, water, animal and human waste for energy production will be investigated. Agriculture, cities and industry produce many waste streams that are not well utilized. Therefore, establishing a renewable energy resource mapping and planning program for electrical generation, waste heat and energy recovery, biomass collection, and biochar, biodiesel and syngas production is critical to regional energy optimization. Electrical storage and demand management are two priorities that will be investigated. Regional scale cooperatives may use electric vehicle batteries and innovations such as pump storage and concentrated solar molten salt heat storage for steam turbine electrical generation. Energy demand management is poorly explored in Canada and elsewhere - our homes and businesses operate on an unrestricted demand. Simple monitoring and energy demand-ranking software can easily reduce peaks demands and move lower ranked uses to non-peak periods, thereby reducing the grid size needed to meet peak demands. Peak demand strains the current energy grid capacity and often requires demand balancing projects and infrastructure that is highly inefficient due to overall low utilization.

Trends of Training Courses Conducted in the Human Resources Development Center of the National Institute for Quantum and Radiological Science and Technology After the Fukushima Dai-Ichi Nuclear Power Plant Accident.

PubMed

Shimizu, Yuko; Iida, Haruzo; Nenoi, Mitsuru

2017-07-01

Environmental contamination with radioactive materials caused by the Fukushima Dai-ichi Nuclear Power Plant (NPP) accident in 2011 raised a serious health concern among residents in Japan, and the demand for radiation experts who can handle the radiation-associated problems has increased. The Human Resources Development Center (HRDC) of the National Institute of for Quantum and Radiological Science and Technology in Japan has offered a variety of training programs covering a wide range of technologies associated with radiation since 1959. In this study, the time-course change in the number and age of the applicants for training programs regularly scheduled at HRDC were analyzed to characterize the demand after the NPP accident. The results suggested that the demand for the training of industrial radiation experts elevated sharply after the NPP accident followed by a prompt decrease, and that young people were likely stimulated to learn the basics of radiation. The demand for the training of medical radiation experts was kept high regardless of the NPP accident. The demand for the training of radiation emergency experts fluctuated apparently with three components: a terminating demand after the criticality accident that occurred in 1999, an urgent demand for handling of the NPP accident, and a sustained demand from local governments that undertook reinforcement of their nuclear disaster prevention program. The demand for the training of school students appeared to be increasing after the NPP accident. It could be foreseen that the demand for training programs targeting young people and medical radiation experts would be elevated in future.

A Note on Comparing the Elasticities of Demand Curves.

ERIC Educational Resources Information Center

Nieswiadomy, Michael

1986-01-01

Demonstrates a simple and useful way to compare the elasticity of demand at each price (or quantity) for different demand curves. The technique is particularly useful for the intermediate microeconomic course. (Author)

A Simultaneous Equation Demand Model for Block Rates

NASA Astrophysics Data System (ADS)

Agthe, Donald E.; Billings, R. Bruce; Dobra, John L.; Raffiee, Kambiz

1986-01-01

This paper examines the problem of simultaneous-equations bias in estimation of the water demand function under an increasing block rate structure. The Hausman specification test is used to detect the presence of simultaneous-equations bias arising from correlation of the price measures with the regression error term in the results of a previously published study of water demand in Tucson, Arizona. An alternative simultaneous equation model is proposed for estimating the elasticity of demand in the presence of block rate pricing structures and availability of service charges. This model is used to reestimate the price and rate premium elasticities of demand in Tucson, Arizona for both the usual long-run static model and for a simple short-run demand model. The results from these simultaneous equation models are consistent with a priori expectations and are unbiased.

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

Effects of Nurses' Perceptions of Actual and Demanded Competence on Turnover Intentions.

PubMed

Takase, Miyuki; Yamamoto, Masako; Sato, Yoko; Imai, Takiko; Kawamoto, Mitsuko

2017-10-01

With the growing focus on continuous professional development, demands placed on nurses to uphold nursing competence have been increasing. This study examined how nurses with different lengths of clinical experience perceived the relationship between their actual competence and the competence they felt was demanded of them, and how this relationship was related to their turnover intentions. Survey questionnaires were distributed to 1,377 nurses, of whom 765 returned usable completed forms. The results showed that across all the groups of clinical experience, nurses perceived the demanded competence levels to be higher than their actual competence levels. However, turnover intentions were not related to nurses' perceptions of demanded competence and were negatively related to perceptions of actual competence. The levels of competence demanded should not be considered as threats for nurses. Improving nurses' competence may reduce their turnover intentions.

Method for estimating power outages and restoration during natural and man-made events

DOEpatents

Omitaomu, Olufemi A.; Fernandez, Steven J.

2016-01-05

A method of modeling electric supply and demand with a data processor in combination with a recordable medium, and for estimating spatial distribution of electric power outages and affected populations. A geographic area is divided into cells to form a matrix. Within the matrix, supply cells are identified as containing electric substations and demand cells are identified as including electricity customers. Demand cells of the matrix are associated with the supply cells as a function of the capacity of each of the supply cells and the proximity and/or electricity demand of each of the demand cells. The method includes estimating a power outage by applying disaster event prediction information to the matrix, and estimating power restoration using the supply and demand cell information of the matrix and standardized and historical restoration information.

Impacts of climate change on sub-regional electricity demand and distribution in the southern United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, Melissa R.; Fernandez, Steven J.; Fu, Joshua S.

New tools are employed to develop an electricity demand map for the southeastern United States at neighborhood resolution to serve as a baseline from which to project increases in electricity demand due to a rise in global and local temperature and to population shifts motivated by increases in extreme weather events due to climate change. We find that electricity demand increases due to temperature rise over the next 40 years have a much smaller impact than those due to large population influx. In addition, we find evidence that some, sections of the national electrical grid are more adaptable to thesemore » population shifts and changing demand than others are; and that detailed projections of changing local electricity demand patterns are viable and important for planning at the urban level.« less

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.

Impacts of climate change on sub-regional electricity demand and distribution in the southern United States

DOE PAGES

Allen, Melissa R.; Fernandez, Steven J.; Fu, Joshua S.; ...

2016-07-25

New tools are employed to develop an electricity demand map for the southeastern United States at neighborhood resolution to serve as a baseline from which to project increases in electricity demand due to a rise in global and local temperature and to population shifts motivated by increases in extreme weather events due to climate change. We find that electricity demand increases due to temperature rise over the next 40 years have a much smaller impact than those due to large population influx. In addition, we find evidence that some, sections of the national electrical grid are more adaptable to thesemore » population shifts and changing demand than others are; and that detailed projections of changing local electricity demand patterns are viable and important for planning at the urban level.« less

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

Physical demands in working life and individual physical capacity.

PubMed

Karlqvist, L; Leijon, O; Härenstam, A

2003-08-01

The purpose of this study was to investigate the prevalence of the excess of metabolic level (metabolic demands in work exceeding one-third of the individual's aerobic capacity) of working men and women today and to describe the population whose metabolic level is exceeded. A second aim was to explore how externally assessed metabolic demands match with the physical function and capacity of working men and women in jobs with the lowest and the highest demands. The aerobic power of each individual (94 men and 94 women) was estimated from heart rate and workload in sub-maximal tests from dynamic legwork on a cycle ergometer. Physical activity was assessed using a task-oriented interview technique. Physical function was measured by tests of muscle endurance in arms, abdomen and legs, handgrip pressure, balance and coordination. The calculation of individual metabolic demands during a "typical working day" showed that 27% of the men and 22% of the women exceeded their metabolic level. The results indicate that the physical fitness is low or somewhat low for two-thirds of the 94 men and for more than one-half of the 94 women. Women in the group with the highest job demands had significantly lower muscle endurance in the abdomen and legs and worse coordination than women in the group with the lowest job demands. Metabolic demands in working life today remain high. This is reflected in a mismatch between individual physical capacity and the physical demands of work for 25% of the population.

Global food demand and the sustainable intensification of agriculture.

PubMed

Tilman, David; Balzer, Christian; Hill, Jason; Befort, Belinda L

2011-12-13

Global food demand is increasing rapidly, as are the environmental impacts of agricultural expansion. Here, we project global demand for crop production in 2050 and evaluate the environmental impacts of alternative ways that this demand might be met. We find that per capita demand for crops, when measured as caloric or protein content of all crops combined, has been a similarly increasing function of per capita real income since 1960. This relationship forecasts a 100-110% increase in global crop demand from 2005 to 2050. Quantitative assessments show that the environmental impacts of meeting this demand depend on how global agriculture expands. If current trends of greater agricultural intensification in richer nations and greater land clearing (extensification) in poorer nations were to continue, ~1 billion ha of land would be cleared globally by 2050, with CO(2)-C equivalent greenhouse gas emissions reaching ~3 Gt y(-1) and N use ~250 Mt y(-1) by then. In contrast, if 2050 crop demand was met by moderate intensification focused on existing croplands of underyielding nations, adaptation and transfer of high-yielding technologies to these croplands, and global technological improvements, our analyses forecast land clearing of only ~0.2 billion ha, greenhouse gas emissions of ~1 Gt y(-1), and global N use of ~225 Mt y(-1). Efficient management practices could substantially lower nitrogen use. Attainment of high yields on existing croplands of underyielding nations is of great importance if global crop demand is to be met with minimal environmental impacts.

Modeling water demand when households have multiple sources of water

NASA Astrophysics Data System (ADS)

Coulibaly, Lassina; Jakus, Paul M.; Keith, John E.

2014-07-01

A significant portion of the world's population lives in areas where public water delivery systems are unreliable and/or deliver poor quality water. In response, people have developed important alternatives to publicly supplied water. To date, most water demand research has been based on single-equation models for a single source of water, with very few studies that have examined water demand from two sources of water (where all nonpublic system water sources have been aggregated into a single demand). This modeling approach leads to two outcomes. First, the demand models do not capture the full range of alternatives, so the true economic relationship among the alternatives is obscured. Second, and more seriously, economic theory predicts that demand for a good becomes more price-elastic as the number of close substitutes increases. If researchers artificially limit the number of alternatives studied to something less than the true number, the price elasticity estimate may be biased downward. This paper examines water demand in a region with near universal access to piped water, but where system reliability and quality is such that many alternative sources of water exist. In extending the demand analysis to four sources of water, we are able to (i) demonstrate why households choose the water sources they do, (ii) provide a richer description of the demand relationships among sources, and (iii) calculate own-price elasticity estimates that are more elastic than those generally found in the literature.

Is This Year's Exam as Demanding as Last Year's? Using a Pilot Method to Evaluate the Consistency of Examination Demands over Time

ERIC Educational Resources Information Center

Crisp, Victoria; Novakovic, Nadezda

2009-01-01

Maintaining standards over time is a much debated topic in the context of national examinations in the UK. This study used a pilot method to compare the demands, over time, of two examination units testing administration. The method involved 15 experts revising a framework of demand types and making paired comparisons of examinations from…

Using Resource Economics to Anticipate Forest Land Use Change in the U.S. Mid-Atlantic Region

Treesearch

Peter J. Parks; Ian W. Hardie; Cheryl A. Tedder; David N. Wear

2000-01-01

Demands for forest, farm, and developed land are evolving in the U.S. mid-Atlantic region. The demand for land in developed uses, as well as demands for various forest and farm products are changing in response to population growth, demographic shifts, and market forces. As demand factors change so do relative land values. Land area in future forest, farm, and...

Material Demand Studies: Materials Sorption of Vaporized Hydrogen Peroxide

DTIC Science & Technology

2010-06-01

SORPTION OF VAPORIZED HYDROGEN PEROXIDE Lawrence R. Procell Zoe A. Hess David G. Gehring Joseph T. Lynn Philip W. Bartram Teri Lalain RESEARCH AND...2010 2. REPORT TYPE Final 3. DATES COVERED (From - To) Nov 2003 - Jul 2005 4. TITLE AND SUBTITLE Material Demand Studies: Materials Sorption of...of office surfaces 33 \\i MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE 1. BACKGROUND The Material Demand effort was

The Effects of Increasing Information Processing Demands on Rating Outcomes.

DTIC Science & Technology

1986-10-01

Resources Research THE EFFECTS OF INCREASING INFORMATION PROCESSING DEMANDS ON RATING OUTCOMES Roseanne J. Foti € and Neil M.A. Hauenstein October...j** ~-- .. ~ 87 7 0O2 p. THE EFFECTS OF INCREASING INFORMATION PROCESSING DEMANDS ON RATING OUTCOMES Roseanne J. Foti and -Neil M.A. Hauenstein...5- % Performance Ratings 2 Effects of Increasing Information Processing Demands on Rating Outcomes Abstract This research investigated the cognitive

A cross-national study on the multidimensional characteristics of the five-item psychological demands scale of the Job Content Questionnaire.

PubMed

Choi, BongKyoo; Kawakami, Norito; Chang, SeiJin; Koh, SangBaek; Bjorner, Jakob; Punnett, Laura; Karasek, Robert

2008-01-01

The five-item psychological demands scale of the Job Content Questionnaire (JCQ) has been assumed to be one-dimensional in practice. To examine whether the scale has sufficient internal consistency and external validity to be treated as a single scale, using the cross-national JCQ datasets from the United States, Korea, and Japan. Exploratory factor analyses with 22 JCQ items, confirmatory factor analyses with the five psychological demands items, and correlations analyses with mental health indexes. Generally, exploratory factor analyses displayed the predicted demand/control/support structure with three and four factors extracted. However, at more detailed levels of exploratory and confirmatory factor analyses, the demands scale showed clear evidence of multi-factor structure. The correlations of items and subscales of the demands scale with mental health indexes were similar to those of the full scale in the Korean and Japanese datasets, but not in the U.S. data. In 4 out of 16 sub-samples of the U.S. data, several significant correlations of the components of the demands scale with job dissatisfaction and life dissatisfaction were obscured by the full scale. The multidimensionality of the psychological demands scale should be considered in psychometric analysis and interpretation, occupational epidemiologic studies, and future scale extension.

Attentional Demand of a Virtual Reality-Based Reaching Task in Nondisabled Older Adults.

PubMed

Chen, Yi-An; Chung, Yu-Chen; Proffitt, Rachel; Wade, Eric; Winstein, Carolee

2015-12-01

Attention during exercise is known to affect performance; however, the attentional demand inherent to virtual reality (VR)-based exercise is not well understood. We used a dual-task paradigm to compare the attentional demands of VR-based and non-VR-based (conventional, real-world) exercise: 22 non-disabled older adults performed a primary reaching task to virtual and real targets in a counterbalanced block order while verbally responding to an unanticipated auditory tone in one third of the trials. The attentional demand of the primary reaching task was inferred from the voice response time (VRT) to the auditory tone. Participants' engagement level and task experience were also obtained using questionnaires. The virtual target condition was more attention demanding (significantly longer VRT) than the real target condition. Secondary analyses revealed a significant interaction between engagement level and target condition on attentional demand. For participants who were highly engaged, attentional demand was high and independent of target condition. However, for those who were less engaged, attentional demand was low and depended on target condition (i.e., virtual > real). These findings add important knowledge to the growing body of research pertaining to the development and application of technology-enhanced exercise for elders and for rehabilitation purposes.

Attentional Demand of a Virtual Reality-Based Reaching Task in Nondisabled Older Adults

PubMed Central

Chen, Yi-An; Chung, Yu-Chen; Proffitt, Rachel; Wade, Eric; Winstein, Carolee

2015-01-01

Attention during exercise is known to affect performance; however, the attentional demand inherent to virtual reality (VR)-based exercise is not well understood. We used a dual-task paradigm to compare the attentional demands of VR-based and non-VR-based (conventional, real-world) exercise: 22 non-disabled older adults performed a primary reaching task to virtual and real targets in a counterbalanced block order while verbally responding to an unanticipated auditory tone in one third of the trials. The attentional demand of the primary reaching task was inferred from the voice response time (VRT) to the auditory tone. Participants' engagement level and task experience were also obtained using questionnaires. The virtual target condition was more attention demanding (significantly longer VRT) than the real target condition. Secondary analyses revealed a significant interaction between engagement level and target condition on attentional demand. For participants who were highly engaged, attentional demand was high and independent of target condition. However, for those who were less engaged, attentional demand was low and depended on target condition (i.e., virtual > real). These findings add important knowledge to the growing body of research pertaining to the development and application of technology-enhanced exercise for elders and for rehabilitation purposes. PMID:27004233

Planning for community resilience to future United States ...

EPA Pesticide Factsheets

Costs of repairing and expanding aging infrastructure and competing demands for water from other sectors such as industry and agriculture are stretching water managers’ abilities to meet essential domestic drinking water needs for future generations. Using Bayesian statistical modeling on past and present water use, we project domestic water demand in the context of four climate scenarios developed by the Intergovernmental Panel on Climate Change as part of the their Special Report on Emission Scenarios (SRES). We compare 2010 demand to projections of domestic water demand for the years 2030, 2060 and 2090 for the four SRES scenarios. Results indicate that the number of counties exceeding fifty percent or greater demand over 2010 levels increases through 2090 for two of the scenarios and plateaus around 2050 for the other two. Counties experiencing the largest increases in water demand are concentrated in the states of California, Texas, and isolated portions of the Mid-West, Southeast, and Mid-Atlantic. Closer examination of the spatial distribution of high demand counties reveals that they are typically found near or adjacent to metropolitan centers, potentially placing greater stress on already taxed systems. Identifying these counties allows for targeted adaptive management and policies, economic incentives, and legislation to be focused towards locations that are potentially the most vulnerable. We describe a new approach for projecting water demand into

DOE Office of Scientific and Technical Information (OSTI.GOV)

Konis, Kyle; Orosz, Michael; Sintov, Nicole

Competition-based “energy saving” interventions are increasingly promoted as an effective strategy for reducing energy consumption in buildings with large occupant controlled electrical loads. However, the factors that drive energy savings in such interventions are not well understood, nor are the impacts of short-term competitions on long-term energy performance. A total of 39 8-occupant suites in a freshman residence hall were instrumented with “smart” electric meters, which recorded circuit-level electricity consumption at 15-minute intervals. During a three-week Fall 2014 competition, suites competed to reduce their overall electricity demand and achieved a 6.4% reduction in whole-building demand overall and a 12% reductionmore » during hours of peak demand (from 12:00 to 19:00), despite peak seasonal temperatures and all-time record electricity demand. Analysis incorporating weather-normalized HVAC demand after the competition showed a significant “rebound” for a large portion of the suites (19), however 12 suites made further reductions, and the remainder maintained demand at the competition level. As a result, we compared energy data with self-reported survey data and identified self-efficacy beliefs, pro-environmental behaviors, and sense of affiliation with other residents of the hall as key factors distinguishing the suites with the greatest and most persistent reductions in demand from suites that maintained or increased demand.« less

Demand characteristics, pre-test attitudes and time-on-task trends in the effects of chewing gum on attention and reported mood in healthy volunteers.

PubMed

Allen, A P; Smith, A P

2012-10-01

Previous research has indicated that chewing gum enhances reported alertness, but has variable effects on attention. Demand characteristics may explain these effects. The current study investigated the effects of gum and demand characteristics on attention and reported mood over time. Participants completed measures of mood and attention, with and without chewing gum. To manipulate demand characteristics, they were told that the hypothesised effect of gum was either positive or negative, or no hypothesis was mentioned. Attitudes towards gum were assessed pre- and post-manipulation. Gum increased reported alertness; this effect was only significant for positive and neutral demand characteristics. Vigilance accuracy was reduced for chewing gum, but only in the fourth minute of the task, and gum reduced focussed attention accuracy, but only for the first 64 trials. Demand characteristics did not moderate time-on-task effects. Gum improved selective attention. A positive effect on response organisation was observed; this was significant when demand characteristics and pre-test attitudes to gum were both negative. The results suggest that demand characteristics moderate effects on self-reported alertness and response organisation, but cannot explain time-on-task effects or variable main effects on other aspects of attention. Copyright © 2012 Elsevier Ltd. All rights reserved.

A model of the demand for Islamic banks debt-based financing instrument

NASA Astrophysics Data System (ADS)

Jusoh, Mansor; Khalid, Norlin

2013-04-01

This paper presents a theoretical analysis of the demand for debt-based financing instruments of the Islamic banks. Debt-based financing, such as through baibithamanajil and al-murabahah, is by far the most prominent of the Islamic bank financing and yet it has been largely ignored in Islamic economics literature. Most studies instead have been focusing on equity-based financing of al-mudharabah and al-musyarakah. Islamic bank offers debt-based financing through various instruments derived under the principle of exchange (ukud al-mu'awadhat) or more specifically, the contract of deferred sale. Under such arrangement, Islamic debt is created when goods are purchased and the payments are deferred. Thus, unlike debt of the conventional bank which is a form of financial loan contract to facilitate demand for liquid assets, this Islamic debt is created in response to the demand to purchase goods by deferred payment. In this paper we set an analytical framework that is based on an infinitely lived representative agent model (ILRA model) to analyze the demand for goods to be purchased by deferred payment. The resulting demand will then be used to derive the demand for Islamic debt. We also investigate theoretically, factors that may have an impact on the demand for Islamic debt.

Design of limited-stop service based on the degree of unbalance of passenger demand

PubMed Central

2018-01-01

This paper presents a limited-stop service for a bus fleet to meet the unbalanced demand of passengers on a bus route and to improve the transit service of the bus route. This strategy includes two parts: a degree assessment of unbalanced passenger demand and an optimization of the limited-stop service. The degree assessment of unbalanced passenger demand, which is based on the different passenger demand between stations and the unbalance of passengers within the station, is used to judge whether implementing the limited-stop service is necessary for a bus route. The optimization of limited-stop service considers the influence of stop skipping action and bus capacity on the left-over passengers to determine the proper skipping stations for the bus fleet serving the entire route by minimizing both the waiting time and in-vehicle time of passengers and the running time of vehicles. A solution algorithm based on genetic algorithm is also presented to evaluate the degree of unbalanced passenger demand and optimize the limited-stop scheme. Then, the proper strategy is tested on a bus route in Changchun city of China. The threshold of degree assessment of unbalanced passenger demand can be calibrated and adapted to different passenger demands. PMID:29505585

Buffering Effect of Job Resources in the Relationship between Job Demands and Work-to-Private-Life Interference: A Study among Health-Care Workers.

PubMed

Viotti, Sara; Converso, Daniela

2016-12-01

The present study aims at investigating whether and how (1) job demands and job resources are associated with work-to-private-life interference (WLI) and (2) job resources moderate the relationship between job demands and WLI. Data were collected by a self-report questionnaire from three hospitals in Italy. The sample consisted of 889 health-care workers. All job demands (i.e., quantitative demands, disproportionate patient expectations, and verbal aggression) and job resources (i.e., job autonomy, support from superiors and colleagues, fairness, and organizational support), with the exception of skill discretion, were related to WLI. The effects of quantitative demands on WLI were moderated by support from superiors; fairness and organizational support moderate the effects of all job demands considered. Support from colleagues moderated only verbal aggression. Job autonomy did not buffer any job demands. The present study suggests that the work context has a central importance in relation to the experience of WLI among health-care workers. The results indicated that intervention in the work context may help to contain WLI. Such interventions would especially be aimed at improving the social climate within the unit and quality of the organizational process.

Design of limited-stop service based on the degree of unbalance of passenger demand.

PubMed

Zhang, Hu; Zhao, Shuzhi; Liu, Huasheng; Liang, Shidong

2018-01-01

This paper presents a limited-stop service for a bus fleet to meet the unbalanced demand of passengers on a bus route and to improve the transit service of the bus route. This strategy includes two parts: a degree assessment of unbalanced passenger demand and an optimization of the limited-stop service. The degree assessment of unbalanced passenger demand, which is based on the different passenger demand between stations and the unbalance of passengers within the station, is used to judge whether implementing the limited-stop service is necessary for a bus route. The optimization of limited-stop service considers the influence of stop skipping action and bus capacity on the left-over passengers to determine the proper skipping stations for the bus fleet serving the entire route by minimizing both the waiting time and in-vehicle time of passengers and the running time of vehicles. A solution algorithm based on genetic algorithm is also presented to evaluate the degree of unbalanced passenger demand and optimize the limited-stop scheme. Then, the proper strategy is tested on a bus route in Changchun city of China. The threshold of degree assessment of unbalanced passenger demand can be calibrated and adapted to different passenger demands.

The role of rewards and demands in burnout among surgical nurses.

PubMed

Basińska, Beata A; Wilczek-Rużyczka, Ewa

2013-08-01

Job rewards have both, an intrinsic and an extrinsic motivational potential, and lead to employees' development as well as help them to achieve work goals. Rewards can balance job demands and protect from burnout. Due to changes on the labour market, new studies are needed. The aim of our study was to examine the role of demands and individual rewards (and their absence) in burnout among surgical nurses. The study was conducted in 2009 and 2010 with 263 nurses who worked in surgical wards and clinics in hospitals in Southern Poland. The hypotheses were tested by the use of measures of demands and rewards (Effort-Reward Imbalance Questionnaire by Siegrist) and burnout syndrome (Maslach Burnout Inventory). A cross-sectional, correlational study design was applied. Nurses experienced the largest deficiencies in salary and prestige. Exhaustion was explained by stronger demands and lack of respect (large effect). Depersonalization was explained by stronger demands, lack of respect and greater job security (medium effect). Reduced personal achievement was explained by more demands and greater job security (small effect). Excessive demands and lack of esteem are key reasons for burnout among surgical nurses. Job security can increase burnout when too many resources are invested and career opportunities do not appear. These results may help to improve human resource management in the healthcare sector.

Patients with HIV/Aids and ulcer risk: nursing care demands.

PubMed

Pereira, Lanara Alves; Feitosa, Manuella Carvalho; Silva, Grazielle Roberta Freitas da; Leite, Illoma Rossany Lima; Silva, Maria Esther; Soares, Rômulo Diego Monte

2016-06-01

to analyze the demand for nursing care and the risk of pressure ulcers (PU) of patients with HIV/Aids. quantitative survey, carried out from December 2012 to March 2013 in a public hospital of Teresina, state of Piauí, Brazil. the sample of 31 patients was predominantly male, mean age 36.6 years, average care demand 49.4%, most showing some risk of developing PU. The variables correlated with PU risk were care demand and clinical outcome (death). Those associated with care demand were age and clinical outcome (death). the results showed that patients require moderate nursing care needs and most of them present risk of developing PU.

Work-family conflict in Japan: how job and home demands affect psychological distress.

PubMed

Shimazu, Akihito; Bakker, Arnold B; Demerouti, Evangelia; Peeters, Maria C W

2010-01-01

The aim of the present study was to examine how job and home demands are related to psychological distress in a sample of Japanese working parents with preschool children (n=196). We expected that job and home demands are partially related to psychological distress through work-to-family conflict (WFC) and family-to-work conflict (FWC), respectively. Structural equation modeling showed that, as expected, home demands were partially related to psychological distress, both directly and indirectly through FWC. In contrast, job demands were only directly related to psychological distress. The differences between the roles of FWC and WFC are discussed using identity theory.

Demand for temporary agency nurses and nursing shortages.

PubMed

Seo, Sukyong; Spetz, Joanne

2013-08-01

There is an ongoing debate about the reasons for the growth of temporary employment of registered nurses (RNs). Some argue that efficiency incentives to increase flexibility and reduce labor costs are the principal cause, while others point to shortages of RNs as the stronger determinant. Using hospital-level data from California's Office of Statewide Health Planning and Development, we find a significant trend of increasing demand for agency nurses during the years of RN shortage. Demand rose with inpatient days, patient demand fluctuation, and the level of fringe benefits. Competition between hospitals and unionization, however, did not affect hospitals' demand for temporary RNs. © The Author(s) 2014.

Effect of task load and task load increment on performance and workload

NASA Technical Reports Server (NTRS)

Hancock, P. A.; Williams, G.

1993-01-01

The goal of adaptive automated task allocation is the 'seamless' transfer of work demand between human and machine. Clearly, at the present time, we are far from this objective. One of the barriers to achieving effortless human-machine symbiosis is an inadequate understanding of the way in which operators themselves seek to reallocate demand among their own personal 'resources.' The paper addresses this through an examination of workload response, which scales an individual's reaction to common levels of experienced external demand. The results indicate the primary driver of performance is the absolute level of task demand over the increment in that demand.

Demand management: enabling patients to use medical care appropriately.

PubMed

Vickery, D M; Lynch, W D

1995-05-01

A rationale is presented for considering demand management as well as supply management (managed care) in the current debate on health care reform. Demand management is the support of individuals so that they may make rational health and medical decisions based on a consideration of benefits and risks. The concept of demand for medical services is examined within a theoretical framework of four components: morbidity, perceived need, patient preference, and nonhealth motives. Two components, perceived need and patient preference, are suggested to offer considerable potential for making utilization more appropriate and reducing costs. Current demand services and potential hazards related to their continued expansion are discussed.

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)

Parent Perceptions of Illness Uncertainty and Child Depressive Symptoms in Juvenile Rheumatic Diseases: Examining Caregiver Demand and Parent Distress as Mediators.

PubMed

Chaney, John M; Gamwell, Kaitlyn L; Baraldi, Amanda N; Ramsey, Rachelle R; Cushing, Christopher C; Mullins, Alexandria J; Gillaspy, Stephen R; Jarvis, James N; Mullins, Larry L

2016-10-01

Examine caregiver demand and general parent distress as mediators in the parent illness uncertainty-child depressive symptom association in youth with juvenile rheumatic diseases. Children and adolescents completed the Child Depression Inventory; caregivers completed the Parent Perceptions of Uncertainty Scale, the Care for My Child with Rheumatic Disease Scale, and the Brief Symptom Inventory. The pediatric rheumatologist provided ratings of clinical disease status. Analyses revealed significant direct associations between illness uncertainty and caregiver demand, and between caregiver demand and both parent distress and child depressive symptoms. Results also revealed significant parent uncertainty → caregiver demand → parent distress and parent uncertainty → caregiver demand → child depressive symptom indirect paths. Results highlight the role of illness appraisals in adjustment to juvenile rheumatic diseases, and provide preliminary evidence that parent appraisals of illness uncertainty impact parent distress and child depressive symptoms indirectly through increased perceptions of caregiver demand. © The Author 2016. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Water demand forecasting: review of soft computing methods.

PubMed

Ghalehkhondabi, Iman; Ardjmand, Ehsan; Young, William A; Weckman, Gary R

2017-07-01

Demand forecasting plays a vital role in resource management for governments and private companies. Considering the scarcity of water and its inherent constraints, demand management and forecasting in this domain are critically important. Several soft computing techniques have been developed over the last few decades for water demand forecasting. This study focuses on soft computing methods of water consumption forecasting published between 2005 and 2015. These methods include artificial neural networks (ANNs), fuzzy and neuro-fuzzy models, support vector machines, metaheuristics, and system dynamics. Furthermore, it was discussed that while in short-term forecasting, ANNs have been superior in many cases, but it is still very difficult to pick a single method as the overall best. According to the literature, various methods and their hybrids are applied to water demand forecasting. However, it seems soft computing has a lot more to contribute to water demand forecasting. These contribution areas include, but are not limited, to various ANN architectures, unsupervised methods, deep learning, various metaheuristics, and ensemble methods. Moreover, it is found that soft computing methods are mainly used for short-term demand forecasting.

The impact of job and family demands on partner’s fatigue: A study of Japanese dual-earner parents

PubMed Central

Shimazu, Akihito; Bakker, Arnold B.; Demerouti, Evangelia; Shimada, Kyoko; Kawakami, Norito

2017-01-01

Objectives This study of Japanese dual-earner couples examined the impact of family and job demands on one’s own and one’s partner’s fatigue as well as gender differences in these effects. Methods A total of 2,502 parents (1,251 couples) were surveyed using a self-administered questionnaire. A crossover model was tested using structural equation modeling. Results The results of structural equation modeling analyses showed that both job and family demands independently exacerbated fatigue. There was an indirect effect of job and family demands on partner fatigue through one’s own fatigue only from husbands to wives. An indirect effect of job demands on partner fatigue through partner’s family demands was identified only from wives to husbands. Furthermore, there were gender differences in the crossover of fatigue. Conclusions This study shows that job and family demands influence family circumstances. When considering means to reduce employees’ fatigue, gender differences in the mechanism of fatigue need to be taken into account. PMID:28235008

The moderating role of personal resources in the relationship between psychosocial job demands and health: a cross-sectional study

PubMed Central

Mayerl, Hannes; Stolz, Erwin; Großschädl, Franziska; Rásky, Éva; Freidl, Wolfgang

2017-01-01

Objective The main objective of this research was to investigate the buffering effects of an individual’s physical, mental and social resources in the relationship between psychosocial job demands and (1) health symptoms, (2) mental strain and (3) the body mass index (BMI), respectively. Methods We performed moderated regression analysis to examine data from a large cross-sectional survey of an Austrian employee sample (n=9434). Results The results revealed a robust association between psychosocial job demands and health symptoms as well as mental strain, but only a weak relationship between psychosocial job demands and BMI. Although the personal resources showed a positive effect on health symptoms and mental strain, only weak evidence was found for the hypothesised interaction with psychosocial job demands. Solely the physical fitness of a person was found to mitigate the impact of psychosocial job demands on health symptoms. Conclusions In conclusion, personal resources substantially accounted for the prediction of health. However, the interactions between psychosocial job demands and personal resources only slightly contributed to explaining the variation in health. PMID:28851776

[A preliminary study on dental-manpower forecasting model of Miyun County in Beijing].

PubMed

Huang, H; Wang, H; Yang, S

1999-01-01

To explore the dental-manpower forecasting model of Chinese rural region and provide references for Chinese dental-manpower researches. Chose rural Miyun County in Beijing as a sample, according to the need-based and demand-weighted forecasting method, a protocol WHO-CH model and corresponding JWG-6-M package developed by authors were used to calculate the present and future need and demand of dental-manpower in Miyun County. Further predications were also calculated on the effects of four modeling parameters to the demand of dental manpower. The present need and demand of oral care personnel for Miyun were 114.5 and 29.1 respectively. At present, Miyun has 43 oral care providers who can satisfy the demand but not the need. The change of oral health demand had a major effect on the forecast of the manpower. Dental-manpower planning should consider the need as a prime factor but must be modified by the demand. It was suggested that corresponding factors of oral care personnel need to be discussed further.

Professional commitment: Does it buffer or intensify job demands?

PubMed

Nesje, Kjersti

2017-04-01

The purpose of this study is to investigate whether professional commitment can be seen as a moderator in the relationship between job demands and emotional exhaustion among Norwegian nurses. Inspired by the job demands-resources model, this study explores whether having a strong commitment to the nursing profession can be seen as a resource that buffers the effect of job demands on emotional exhaustion or, conversely, intensifies the impact of job demands. A survey that comprised Norwegian nurses who had graduated three years previously (N = 388) was conducted. Multiple regression was performed to test the hypothesis. The results provide support to a buffering effect; thus, individuals with a higher degree of professional commitment conveyed a weaker association between job demands and emotional exhaustion compared with nurses with a lower degree of commitment. Developing a better understanding of the potential buffering effect of professional commitment is of great interest. The present study is the first to utilize professional commitment as a resource within the job demands-resources framework. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Balancing Demands and Resources in Sport: Adaptation and Validation of the Demand-Induced Strain Compensation Questionnaire for Use in Sport.

PubMed

Balk, Yannick A; De Jonge, Jan; Oerlemans, Wido G M; Geurts, Sabine A E; Fletcher, David; Dormann, Christian

2018-06-01

Too high demands, combined with a lack of resources, are often detrimental to athletic health and well-being. However, a valid and reliable instrument to investigate different dimensions of demands and resources in sport is currently unavailable. Therefore, the present study examines the psychometric properties of an existing and well-validated survey instrument on demands and resources at task-level that was adapted to sport. This instrument, the Demand-Induced Strain Compensation Questionnaire for Sport (DISQ-SPORT), was empirically tested among 1,101 athletes (416 females and 685 males) from a variety of sports and in different languages. Results supported the proposed six-factor structure of the instrument, consisting of physical, cognitive, and emotional demands and resources. Internal consistencies of all subscales were satisfactory and the instrument was invariant across type of sport, competitive level and language. Continued evaluation of the psychometric properties of the DISQ-SPORT, especially in terms of content validity and test-retest stability, is nevertheless warranted. Theoretical and practical implications as well as areas for future research are discussed.

Psychosocial work environment and health in U.S. metropolitan areas: a test of the demand-control and demand-control-support models.

PubMed

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.

Beliefs about willpower moderate the effect of previous day demands on next day’s expectations and effective goal striving

PubMed Central

Bernecker, Katharina; Job, Veronika

2015-01-01

Research suggests that beliefs about willpower affect self-regulation following previous self-regulatory demands (Job et al., 2010). Some people believe that their willpower is limited, meaning that after a demanding task it needs to be replenished (limited theory). By contrast, others believe that willpower is not limited and that previous self-control tasks even activate willpower (non-limited theory). We hypothesized that when people experience a demanding day their beliefs about willpower predict their expected capacity to self-regulate and their actual self-regulation on the following day. In a daily diary study (N = 157), we measured students’ daily level of demands, their expected performance in unpleasant tasks, and their effective goal striving. Results showed that following a demanding day, students with a non-limited theory had higher expectations about their progress in unpleasant tasks and were striving more efficiently for their goals than students with a limited theory. These findings suggest that beliefs about willpower affect whether demands experienced on a previous day have positive or negative consequences on people’s self-regulation. PMID:26528198

Aging and the Vulnerability of Speech to Dual Task Demands

PubMed Central

Kemper, Susan; Schmalzried, RaLynn; Hoffman, Lesa; Herman, Ruth

2010-01-01

Tracking a digital pursuit rotor task was used to measure dual task costs of language production by young and older adults. Tracking performance by both groups was affected by dual task demands: time on target declined and tracking error increased as dual task demands increased from the baseline condition to a moderately demanding dual task condition to a more demanding dual task condition. When dual task demands were moderate, older adults’ speech rate declined but their fluency, grammatical complexity, and content were unaffected. When the dual task was more demanding, older adults’ speech, like young adults’ speech, became highly fragmented, ungrammatical, and incoherent. Vocabulary, working memory, processing speed, and inhibition affected vulnerability to dual task costs: vocabulary provided some protection for sentence length and grammaticality, working memory conferred some protection for grammatical complexity, and processing speed provided some protection for speech rate, propositional density, coherence, and lexical diversity. Further, vocabulary and working memory capacity provided more protection for older adults than for young adults although the protective effect of processing speed was somewhat reduced for older adults as compared to the young adults. PMID:21186917

Assessing Unmet and Latent Demand for Pharmacists at the State Level

PubMed Central

Arora, Prachi; Mott, David A.; Chui, Michelle A.; Kreling, David H.

2016-01-01

Background Past reports suggest that a near balance has been reached in the supply and demand for pharmacists in the US. Although data on the level of supply of pharmacists is available, there is no continuous and systematic tracking of the level of demand (unmet and latent) for pharmacists at state level. Unmet demand, an established construct in pharmacy workforce, is important to measure the number of vacancies and assess pharmacist shortage consistently over time. Latent demand or potential demand is a novel construct and has never been measured in pharmacy workforce. With the increase in supply, it is important to measure the potential demand that could be budgeted in pharmacies in the near future. Objective The objective of this study was to measure the unmet and latent demand for pharmacists and explore the association between latent demand and workload characteristics in community and hospital pharmacies in Wisconsin in 2011-12. Methods The study used a cross-sectional, descriptive survey design. A sample of community pharmacies (n=1,064) and hospital pharmacies (n=126) licensed in Wisconsin in 2011-12 was identified. Key informants (managers/owners) of sampled pharmacies were sent a one-page cover letter explaining the purpose of the study and requesting participation and a three page survey form. The main outcome measures of the study were total number of FTE pharmacist positions vacant, presence of adequate staff size, additional number of FTE pharmacist positions needed to attain adequate staff size, prescription volume, daily census, hospital size and number of hours prescription department is open. Descriptive statistics were calculated for all the pharmacies collectively, then separately for community and hospital pharmacies. Pharmacy setting, vacancies and workload characteristics of pharmacies with and without latent demand were compared using chi-squared test of independence and/or t-test. Sample weights were calculated and used in all the analyses to weigh the estimates to all pharmacies in Wisconsin. Results Overall response rate to the survey was 50.1%. Of the total number of FTE pharmacist positions budgeted in Wisconsin, 54.3 FTE positions (1.5%) were reported vacant in 2011-12. Approximately 28.2% of the community and hospital pharmacies reported the presence of latent demand. Latent demand was significantly associated with higher workload in community pharmacies and larger bed size in hospital pharmacies. Conclusion There appeared to be a balance between the supply and demand for pharmacists in Wisconsin in 2011-12. There is a potential for additional FTE positions (latent demand) to be budgeted in pharmacies to attain adequate pharmacist staff size. It is important to consistently track the level of unmet and latent demand for pharmacists in Wisconsin and combine this information with other workforce characteristics to guide the decision making of pharmacy workforce planners and pharmacy managers. PMID:27330846

Mobility on Demand Operational Concept Report.

DOT National Transportation Integrated Search

2017-09-10

This operational concept report provides an overview of the Mobility on Demand (MOD) concept and its evolution, description of the MOD ecosystem in a supply and demand framework, and its stakeholders and enablers. Leveraging the MOD ecosystem framewo...

A Demanding Public.

ERIC Educational Resources Information Center

Coleman, Diane J.; Monger, Joyce R.

1992-01-01

This curriculum unit, intended for use with gifted students and others, uses the daily activities of a zoo gift shop to teach principles of economics including the law of demand, the nature of a market, and influences on product demand. (DB)

Physical Therapy and Occupational Therapy: Suggested Readings [and] Physical Therapy: Supply/Demand--Some Facts [and] Occupational Therapy: Supply and Demand--Some Facts. Information on Personnel Supply and Demand.

ERIC Educational Resources Information Center

National Clearinghouse for Professions in Special Education, Reston, VA.

Brought together are two fact sheets on the supply of and demand for physical therapists and occupational therapists. The fact sheets cite statistical data from the National Easter Seal Society, the American Physical Therapy Association, and the American Occupational Therapy Association. The cited facts focus on the need to recruit and retain…

The Market Demand for Air Transportation

NASA Technical Reports Server (NTRS)

Taneja, N.

1972-01-01

Although the presentation will touch upon the areas of market for air transportation, the theoretical foundations of the demand function, the demand models, and model selection and evaluation, the emphasis of the presentation will be on a qualitative description of the factors affecting the demand for air transportation. The presentation will rely heavily on the results of market surveys carried out by the Port of New York Authority, the University of Michigan, and Census of Transportation.

An Update to the Budget and Economic Outlook: 2016 to 2026

DTIC Science & Technology

2016-08-01

increased the demand for Treasury securities. The Labor Market According to CBO’s estimates, the growth in output will heighten demand for labor...over the next year and a half, leading to solid employment gains and eliminating labor market slack in 2017, thereby putting upward pressure on wages... markets and recent global economic developments that point to less demand for foreign assets and greater demand for U.S. Treasury securities. It also

Battery resource assessment. Battery demands scenarios materials

NASA Astrophysics Data System (ADS)

Sullivan, D.

1980-12-01

Projections of demand for batteries and battery materials between 1980 and 2000 are presented. The estimates are based on existing predictions for the future of the electric vehicle, photovoltaic, utility load-leveling, and existing battery industry. Battery demand was first computed as kilowatt-hours of storage for various types of batteries. Using estimates for the materials required for each battery, the maximum demand that could be expected for each battery material was determined.

Exploring the Basis for Gender Differences in the Demand-Withdraw Pattern

PubMed Central

Holley, Sarah R.; Sturm, Virginia E.; Levenson, Robert W.

2010-01-01

During marital conflict, wives tend to demand and husbands tend to withdraw. These behaviors were historically thought to stem from essential differences between men and women. An alternative explanation implicates one form of power differences—wives desire more change and therefore demand, whereas husbands desire less change and withdraw to maintain status quo. Studying same-sex as well as cross-sex couples enables an evaluation of both explanations. We examined demand-withdraw behaviors in 63 heterosexual, gay, and lesbian couples. The demand-withdraw pattern was seen regardless of type of couple. Further, for all couples, differences in the amount of change desired in partners during a conflict interaction predicted differences in demand and withdraw behaviors. These results offer further evidence that an oft-observed difference in heterosexual relationships may result from social conventions that afford men greater power and women less power. PMID:20455136

Enhancing perceptual and attentional skills requires common demands between the action video games and transfer tasks.

PubMed

Oei, Adam C; Patterson, Michael D

2015-01-01

Despite increasing evidence that shows action video game play improves perceptual and cognitive skills, the mechanisms of transfer are not well-understood. In line with previous work, we suggest that transfer is dependent upon common demands between the game and transfer task. In the current study, participants played one of four action games with varying speed, visual, and attentional demands for 20 h. We examined whether training enhanced performance for attentional blink, selective attention, attending to multiple items, visual search and auditory detection. Non-gamers who played the game (Modern Combat) with the highest demands showed transfer to tasks of attentional blink and attending to multiple items. The game (MGS Touch) with fewer attentional demands also decreased attentional blink, but to a lesser degree. Other games failed to show transfer, despite having many action game characteristics but at a reduced intensity. The results support the common demands hypothesis.

Job demands and job performance: the mediating effect of psychological and physical strain and the moderating effect of role clarity.

PubMed

Lang, Jessica; Thomas, Jeffrey L; Bliese, Paul D; Adler, Amy B

2007-04-01

The aims of the present study were twofold: First, in differentiating between specific job characteristics, the authors examined the moderating influence of role clarity on the relationship between job demands and psychological and physical strain. Second, in providing a more comprehensive link between job demands and job performance, the authors examined strain as a mediator of that relationship. Participants were 1,418 Army cadets attending a 35-day assessment center. Survey data were collected on Day 26 of the assessment center and performance ratings were assessed throughout the assessment center period by expert evaluators. Role clarity was found to moderate the job demands-strain relationship. Specifically, cadets experiencing high demands reported less physical and psychological strain when they reported high role clarity. Moreover, psychological strain significantly mediated the demands-performance relationship. Implications are discussed from theoretical and applied perspectives. Copyright (c) 2007 APA, all rights reserved.

The price elasticity of demand for heroin: matched longitudinal and experimental evidence#

PubMed Central

Olmstead, Todd A.; Alessi, Sheila M.; Kline, Brendan; Pacula, Rosalie Liccardo; Petry, Nancy M.

2015-01-01

This paper reports estimates of the price elasticity of demand for heroin based on a newly constructed dataset. The dataset has two matched components concerning the same sample of regular heroin users: longitudinal information about real-world heroin demand (actual price and actual quantity at daily intervals for each heroin user in the sample) and experimental information about laboratory heroin demand (elicited by presenting the same heroin users with scenarios in a laboratory setting). Two empirical strategies are used to estimate the price elasticity of demand for heroin. The first strategy exploits the idiosyncratic variation in the price experienced by a heroin user over time that occurs in markets for illegal drugs. The second strategy exploits the experimentally-induced variation in price experienced by a heroin user across experimental scenarios. Both empirical strategies result in the estimate that the conditional price elasticity of demand for heroin is approximately −0.80. PMID:25702687

Study of the possibilities of more rational use of energy in the sector of trade and commerce, part 2

NASA Astrophysics Data System (ADS)

Ebersbach, K. F.; Fischer, A.; Layer, G.; Steinberger, W.; Wegner, M.; Wiesner, B.

1982-07-01

The energy demand in the sector of trade and commerce was registered and analyzed. Measures to improve the energy demand structure are presented. In several typical firms like hotels, office buildings, locksmith's shops, motor vehicle repair shops, butcher's shops, laundries and bakeries, detailed surveys of energy consumption were done and included in a statistic evaluation. Subjects analyzed were: development of the energy supply; technology of energy application; final energy demand broken down into demand for light, power, space heating and process heat as well as the demand for cooling; daily and annual load curves of energy consumption and their dependence on various parameters; and measures to improve the structure of energy demand. Detailed measurement points out negligences in the surveyed firms and shows possibilities for likely energy savings. In addition, standard values for specific energy consumption are obtained.

Study of the possibilities of more rational use of energy in the sector of trade and commerce, part 1

NASA Astrophysics Data System (ADS)

Ebersbach, K. F.; Fischer, A.; Layer, G.; Steinberger, W.; Wegner, M.; Wiesner, B.

1982-06-01

The energy demand in trade and commerce was analyzed. Measures to improve the energy demand structure are presented. In several typical firms, like hotels, office buildings, locksmith's shops, motor vehicle repair shops, butcher's shops, laundries and bakeries, energy consumption was surveyed and statistically evaluated. Subjects analyzed are: the development of the energy supply; the technology of energy application; the final energy demand broken down into demand for light, power, space heating and process heat as well as the demand for cooling; the daily and annual load curve of energy consumption and its dependence on various parameters; and measures to improve the structure of energy demand. The detailed measurement points out negligences in the surveyed firms and shows some possibilities for likely energy savings. In addition, standard values for specific energy consumption are obtained.

Expanding Regional Airport Usage to Accommodate Increased Air Traffic Demand

NASA Technical Reports Server (NTRS)

Russell, Carl R.

2009-01-01

Small regional airports present an underutilized source of capacity in the national air transportation system. This study sought to determine whether a 50 percent increase in national operations could be achieved by limiting demand growth at large hub airports and instead growing traffic levels at the surrounding regional airports. This demand scenario for future air traffic in the United States was generated and used as input to a 24-hour simulation of the national airspace system. Results of the demand generation process and metrics predicting the simulation results are presented, in addition to the actual simulation results. The demand generation process showed that sufficient runway capacity exists at regional airports to offload a significant portion of traffic from hub airports. Predictive metrics forecast a large reduction of delays at most major airports when demand is shifted. The simulation results then show that offloading hub traffic can significantly reduce nationwide delays.

Interactive associations of parental support, demands, and psychological control, over adolescents' beliefs about the legitimacy of parental authority.

PubMed

Mellado, Carlos; Cumsille, Patricio; Martínez, M Loreto

2018-04-01

The present study examined the relationship between parental support, demand, psychological control and adolescents' beliefs about the legitimacy of parental authority for personal and multifaceted issues in a sample of 1342 Chilean adolescents (M = 16.38, SD = 1.24, age range 14-20). Results from multiple regression analyses separated by age indicated that demand was positively associated with adolescents' beliefs about the legitimacy of parental authority for personal and multifaceted issues and that psychological control was negatively associated with adolescents' legitimacy beliefs concerning personal issues. Furthermore, parental support moderated the relationship between parental demand and adolescents' beliefs about parental legitimacy for personal and multifaceted issues: those who display high levels of demand showed stronger beliefs about parental legitimacy at high level of support. These results support the interactive effect of parental support and demand on adolescent development. Copyright © 2018. Published by Elsevier Ltd.

Assessment of utility side financial benefits of demand side management considering environmental impacts

NASA Astrophysics Data System (ADS)

Abeygunawardane, Saranga Kumudu

2018-02-01

Any electrical utility prefers to implement demand side management and change the shape of the demand curve in a beneficial manner. This paper aims to assess the financial gains (or losses) to the generating sector through the implementation of demand side management programs. An optimization algorithm is developed to find the optimal generation mix that minimizes the daily total generating cost. This daily total generating cost includes the daily generating cost as well as the environmental damage cost. The proposed optimization algorithm is used to find the daily total generating cost for the base case and for several demand side management programs using the data obtained from the Sri Lankan power system. Results obtained for DSM programs are compared with the results obtained for the base case to assess the financial benefits of demand side management to the generating sector.

The effect of waiting times on demand and supply for elective surgery: Evidence from Italy.

PubMed

Riganti, Andrea; Siciliani, Luigi; Fiorio, Carlo V

2017-09-01

Waiting times are a major policy concern in publicly funded health systems across OECD countries. Economists have argued that, in the presence of excess demand, waiting times act as nonmonetary prices to bring demand for and supply of health care in equilibrium. Using administrative data disaggregated by region and surgical procedure over 2010-2014 in Italy, we estimate demand and supply elasticities with respect to waiting times. We employ linear regression models with first differences and instrumental variables to deal with endogeneity of waiting times. We find that demand is inelastic to waiting times while supply is more elastic. Estimates of demand elasticity are between -0.15 to -0.24. Our results have implications on the effectiveness of policies aimed at increasing supply and their ability to reduce waiting times. Copyright © 2017 John Wiley & Sons, Ltd.

Perceived demands during modern military operations.

PubMed

Boermans, Sylvie M; Kamphuis, Wim; Kamhuis, Wim; Delahaij, Roos; Korteling, J E Hans; Euwema, Martin C

2013-07-01

Using a cross-sectional design, this study explored operational demands during the International Security Assistance Force for Afghanistan (2009-2010) across distinct military units. A total of 1,413 Dutch soldiers, nested within four types of units (i.e., combat, combat support, service support, and command support units) filled out a 23-item self-survey in which they were asked to evaluate the extent to which they experienced operational characteristics as demanding. Exploratory factor analysis identified six underlying dimensions of demands. Multivariate analysis of variance revealed that distinct units are characterized by their own unique constellation of perceived demands, even after controlling for previous deployment experience. Most notable findings were found when comparing combat units to other types of units. These insights can be used to better prepare different types of military units for deployment, and support them in the specific demands they face during deployment. Reprint & Copyright © 2013 Association of Military Surgeons of the U.S.

Enhancing perceptual and attentional skills requires common demands between the action video games and transfer tasks

PubMed Central

Oei, Adam C.; Patterson, Michael D.

2015-01-01

Despite increasing evidence that shows action video game play improves perceptual and cognitive skills, the mechanisms of transfer are not well-understood. In line with previous work, we suggest that transfer is dependent upon common demands between the game and transfer task. In the current study, participants played one of four action games with varying speed, visual, and attentional demands for 20 h. We examined whether training enhanced performance for attentional blink, selective attention, attending to multiple items, visual search and auditory detection. Non-gamers who played the game (Modern Combat) with the highest demands showed transfer to tasks of attentional blink and attending to multiple items. The game (MGS Touch) with fewer attentional demands also decreased attentional blink, but to a lesser degree. Other games failed to show transfer, despite having many action game characteristics but at a reduced intensity. The results support the common demands hypothesis. PMID:25713551

Estimating relative demand for wildlife: Conservation activity indicators

NASA Astrophysics Data System (ADS)

Gray, Gary G.; Larson, Joseph S.

1982-09-01

An alternative method of estimating relative demand among nonconsumptive uses of wildlife and among wildlife species is proposed. A demand intensity score (DIS), derived from the relative extent of an individual's involvement in outdoor recreation and conservation activities, is used as a weighting device to adjust the importance of preference rankings for wildlife uses and wildlife species relative to other members of a survey population. These adjusted preference rankings were considered to reflect relative demand levels (RDLs) for wildlife uses and for species by the survey population. This technique may be useful where it is not possible or desirable to estimate demand using traditional economic means. In one of the findings from a survey of municipal conservation commission members in Massachusetts, presented as an illustration of this methodology, poisonous snakes were ranked third in preference among five groups of reptiles. The relative demand level for poisonous snakes, however, was last among the five groups.

America's water: Agricultural water demands and the response of groundwater

NASA Astrophysics Data System (ADS)

Ho, M.; Parthasarathy, V.; Etienne, E.; Russo, T. A.; Devineni, N.; Lall, U.

2016-07-01

Agricultural, industrial, and urban water use in the conterminous United States (CONUS) is highly dependent on groundwater that is largely drawn from nonsurficial wells (>30 m). We use a Demand-Sensitive Drought Index to examine the impacts of agricultural water needs, driven by low precipitation, high agricultural water demand, or a combination of both, on the temporal variability of depth to groundwater across the CONUS. We characterize the relationship between changes in groundwater levels, agricultural water deficits relative to precipitation during the growing season, and winter precipitation. We find that declines in groundwater levels in the High Plains aquifer and around the Mississippi River Valley are driven by groundwater withdrawals used to supplement agricultural water demands. Reductions in agricultural water demands for crops do not, however, lead to immediate recovery of groundwater levels due to the demand for groundwater in other sectors in regions such as Utah, Maryland, and Texas.

Can hospitals compete on quality? Hospital competition.

PubMed

Sadat, Somayeh; Abouee-Mehrizi, Hossein; Carter, Michael W

2015-09-01

In this paper, we consider two hospitals with different perceived quality of care competing to capture a fraction of the total market demand. Patients select the hospital that provides the highest utility, which is a function of price and the patient's perceived quality of life during their life expectancy. We consider a market with a single class of patients and show that depending on the market demand and perceived quality of care of the hospitals, patients may enjoy a positive utility. Moreover, hospitals share the market demand based on their perceived quality of care and capacity. We also show that in a monopoly market (a market with a single hospital) the optimal demand captured by the hospital is independent of the perceived quality of care. We investigate the effects of different parameters including the market demand, hospitals' capacities, and perceived quality of care on the fraction of the demand that each hospital captures using some numerical examples.

Physical work demands and physical fitness in low social classes--30-year ischemic heart disease and all-cause mortality in the Copenhagen Male Study.

PubMed

Holtermann, Andreas; Mortensen, Ole Steen; Burr, Hermann; Søgaard, Karen; Gyntelberg, Finn; Suadicani, Poul

2011-11-01

Investigate whether high physical work demands increase risk of ischemic heart disease (IHD) mortality among men of low social class with low physical fitness. Thirty-year follow-up in the Copenhagen Male Study of 5249 men aged 40 to 59 years without cardiovascular disease. Physical fitness was estimated using the Åstrand cycling test, and physical work demands determined by two self-reported questions. Among 2707 low social class men, multiple-adjusted Cox proportional hazard ratios showed an almost threefold increased risk of IHD mortality among men with high physical work demands and low physical fitness, but not among men with a high physical fitness, referencing men with low physical work demands. These findings among low social class men support that high physical work demands increases the risk of IHD mortality among those with low physical fitness.

Efforts to monitor Global progress on individual and community demand for immunization: Development of definitions and indicators for the Global Vaccine Action Plan Strategic Objective 2.

PubMed

Hickler, Benjamin; MacDonald, Noni E; Senouci, Kamel; Schuh, Holly B

2017-06-16

The Second Strategic Objective of the Global Vaccine Action Plan, "individuals and communities understand the value of vaccines and demand immunization as both their right and responsibility", differs from the other five in that it does not focus on supply-side aspects of immunization programs but rather on public demand for vaccines and immunization services. This commentary summarizes the work (literature review, consultations with experts, and with potential users) and findings of the UNICEF/World Health Organization Strategic Objective 2 informal Working Group on Vaccine Demand, which developed a definition for demand and indicators related to Strategic Objective 2. Demand for vaccines and vaccination is a complex concept that is not external to supply systems but rather encompasses the interaction between human behaviors and system structure and dynamics. Copyright © 2017. Published by Elsevier Ltd.

Ad libitum or demand/semi-demand feeding versus scheduled interval feeding for preterm infants.

PubMed

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.

Effects of low sink demand on leaf photosynthesis under potassium deficiency.

PubMed

Pan, Yonghui; Lu, Zhifeng; Lu, Jianwei; Li, Xiaokun; Cong, Rihuan; Ren, Tao

2017-04-01

The interaction between low sink demand and potassium (K) deficiency in leaf photosynthesis was not intensively investigated, therefore this interaction was investigated in winter oilseed rape (Brassica napus L.). Plants subjected to sufficient (+K) or insufficient (-K) K supply treatments were maintained or removed their flowers and pods; these conditions were defined as high sink demand (HS) or low sink demand (LS), respectively. The low sink demand induced a lower photosynthetic rate (P n ), especially in the -K treatment during the first week. A negative relationship between P n and carbohydrate concentration was observed in the -K treatment but not in the +K treatment, suggesting that the decrease in P n in the -K treatment was the result of sink feedback regulation under low sink demand. Longer sink removal duration increased carbohydrate concentration, but the enhanced assimilate did not influence P n . On the contrary, low sink demand resulted in a high K concentration, slower chloroplast degradation rate and better PSII activity, inducing a higher P n compared with HS. Consequently, low sink demand decreased leaf photosynthesis over the short term due to sink feedback regulation, and potassium deficiency enhanced the photosynthetic decrease through carbohydrate accumulation and a lower carbohydrate concentration threshold for initiating photosynthesis depression. A longer duration of limited sink demand and sufficient potassium supply resulted in a higher photosynthesis rate because of delayed chloroplast degradation. This finding indicates that the nutritional status plays a role in leaf photosynthesis variations due to sink-source manipulation. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Motor demands impact speed of information processing in Autism Spectrum Disorders

PubMed Central

Kenworthy, Lauren; Yerys, Benjamin E.; Weinblatt, Rachel; Abrams, Danielle N.; Wallace, Gregory L.

2015-01-01

Objective The apparent contradiction between preserved or even enhanced perceptual processing speed on inspection time tasks in autism spectrum disorders (ASD) and impaired performance on complex processing speed tasks that require motor output (e.g. Wechsler Processing Speed Index) has not yet been systematically investigated. This study investigates whether adding motor output demands to an inspection time task impairs ASD performance compared to that of typically developing control (TDC) children. Method The performance of children with ASD (n=28; mean FSIQ=115) and TDC (n=25; mean FSIQ=122) children was compared on processing speed tasks with increasing motor demand. Correlations were run between ASD task performance and Autism Diagnostic Observation Schedule (ADOS) Communication scores. Results Performance by the ASD and TDC groups on a simple perceptual processing speed task with minimal motor demand was equivalent, though it diverged (ASD worse than TDC) on two tasks with the same stimuli, but increased motor output demands. ASD performance on the moderate but not the high speeded motor output demand task was negatively correlated with ADOS communication symptoms. Conclusions These data address the apparent contradiction between preserved inspection time in the context of slowed “processing speed” in ASD. They show that processing speed is preserved when motor demands are minimized, but that increased motor output demands interfere with the ability to act on perceptual processing of simple stimuli. Reducing motor demands (e.g. through the use of computers) may increase the capacity of people with ASD to demonstrate good perceptual processing in a variety of educational, vocational and social settings. PMID:23937483

[Application of job demands-resources model in research on relationships between job satisfaction, job resources, individual resources and job demands].

PubMed

Potocka, Adrianna; Waszkowska, Małgorzata

2013-01-01

The aim of this study was to explore the relationships between job demands, job resourses, personal resourses and job satisfaction and to assess the usefulness of the Job Demands-Resources (JD-R) model in the explanation of these phenomena. The research was based on a sample of 500 social workers. The "Psychosocial Factors" and "Job satisfaction" questionnaires were used to test the hypothesis. The results showed that job satisfaction increased with increasing job accessibility and personal resources (r = 0.44; r = 0.31; p < 0.05). The analysis of variance (ANOVA) indicated that job resources and job demands [F(1.474) = 4.004; F(1.474) = 4.166; p < 0.05] were statistically significant sources of variation in job satisfaction. Moreover, interactions between job demands and job resources [F(3,474) = 2.748; p <0.05], as well as between job demands and personal resources [F(3.474) = 3.021; p <0.05] had a significant impact on job satisfaction. The post hoc tests showed that 1) in low job demands, but high job resources employees declared higher job satisfaction, than those who perceived them as medium (p = 0.0001) or low (p = 0.0157); 2) when the level of job demands was perceived as medium, employees with high personal resources declared significantly higher job satisfaction than those with low personal resources (p = 0.0001). The JD-R model can be used to investigate job satisfaction. Taking into account fundamental factors of this model, in organizational management there are possibilities of shaping job satisfaction among employees.

Interrole conflict and self-efficacy to manage work and family demands mediate the relationships of job and family demands with stress in the job and family domains.

PubMed

Smoktunowicz, Ewelina; Cieslak, Roman; Demerouti, Evangelia

2017-09-01

This study derives from Work-Home Resources model (ten Brummelhuis, L. L., & Bakker, A. B. (2012). A resource perspective on the work-home interface: The work-home resources model. American Psychologist, 67(7), 545-556. doi: 10.1037/a0027974 ) and Social Cognitive Theory (Bandura, A. (1986). Social foundations of thought and action: A social cognitive theory. Englewood Cliffs, NJ, US: Prentice-Hall, Inc.) to investigate mechanisms responsible for the effect of job and family demands on work- and family-related perceived stress. We hypothesized that interrole conflict and self-efficacy to manage work and family demands operate either independently or sequentially transmitting the effects of demands on perceived stress. A sample of 100 employees of various occupations participated in the study conducted online in two waves: Time 1 (T1) and Time 2 (T2) with a three-month interval. Regression analysis with bootstrapping was applied. Interrole conflict (T1) did not mediate the relationships between demands (T1) and perceived stress (T2), whereas self-efficacy (T1) mediated only those between family demands (T1) and stress (T2). However, data supported the sequential mediation hypotheses: Demands (T1) were associated with increased interrole conflict (T1) which in turn decreased self-efficacy (T1) and ultimately resulted in the elevated perceived stress at work and in the family (T2). Demands originating in one domain can impact stress both in the same and other life areas through the sequence of interrole conflict and context-specific self-efficacy.

A multi-paradigm framework to assess the impacts of climate change on end-use energy demand.

PubMed

Nateghi, Roshanak; Mukherjee, Sayanti

2017-01-01

Projecting the long-term trends in energy demand is an increasingly complex endeavor due to the uncertain emerging changes in factors such as climate and policy. The existing energy-economy paradigms used to characterize the long-term trends in the energy sector do not adequately account for climate variability and change. In this paper, we propose a multi-paradigm framework for estimating the climate sensitivity of end-use energy demand that can easily be integrated with the existing energy-economy models. To illustrate the applicability of our proposed framework, we used the energy demand and climate data in the state of Indiana to train a Bayesian predictive model. We then leveraged the end-use demand trends as well as downscaled future climate scenarios to generate probabilistic estimates of the future end-use demand for space cooling, space heating and water heating, at the individual household and building level, in the residential and commercial sectors. Our results indicated that the residential load is much more sensitive to climate variability and change than the commercial load. Moreover, since the largest fraction of the residential energy demand in Indiana is attributed to heating, future warming scenarios could lead to reduced end-use demand due to lower space heating and water heating needs. In the commercial sector, the overall energy demand is expected to increase under the future warming scenarios. This is because the increased cooling load during hotter summer months will likely outpace the reduced heating load during the more temperate winter months.

A multi-paradigm framework to assess the impacts of climate change on end-use energy demand

PubMed Central

Nateghi, Roshanak

2017-01-01

Projecting the long-term trends in energy demand is an increasingly complex endeavor due to the uncertain emerging changes in factors such as climate and policy. The existing energy-economy paradigms used to characterize the long-term trends in the energy sector do not adequately account for climate variability and change. In this paper, we propose a multi-paradigm framework for estimating the climate sensitivity of end-use energy demand that can easily be integrated with the existing energy-economy models. To illustrate the applicability of our proposed framework, we used the energy demand and climate data in the state of Indiana to train a Bayesian predictive model. We then leveraged the end-use demand trends as well as downscaled future climate scenarios to generate probabilistic estimates of the future end-use demand for space cooling, space heating and water heating, at the individual household and building level, in the residential and commercial sectors. Our results indicated that the residential load is much more sensitive to climate variability and change than the commercial load. Moreover, since the largest fraction of the residential energy demand in Indiana is attributed to heating, future warming scenarios could lead to reduced end-use demand due to lower space heating and water heating needs. In the commercial sector, the overall energy demand is expected to increase under the future warming scenarios. This is because the increased cooling load during hotter summer months will likely outpace the reduced heating load during the more temperate winter months. PMID:29155862

High Job Demands, Still Engaged and Not Burned Out? The Role of Job Crafting.

PubMed

Hakanen, Jari J; Seppälä, Piia; Peeters, Maria C W

2017-08-01

Traditionally, employee well-being has been considered as resulting from decent working conditions arranged by the organization. Much less is known about whether employees themselves can make self-initiated changes to their work, i.e., craft their jobs, in order to stay well, even in highly demanding work situations. The aim of this study was to use the job demands-resources (JD-R model) to investigate whether job crafting buffers the negative impacts of four types of job demands (workload, emotional dissonance, work contents, and physical demands) on burnout and work engagement. A questionnaire study was designed to examine the buffering role of job crafting among 470 Finnish dentists. All in all, 11 out of 16 possible interaction effects of job demands and job crafting on employee well-being were significant. Job crafting particularly buffered the negative effects of job demands on burnout (7/8 significant interactions) and to a somewhat lesser extent also on work engagement (4/8 significant interactions). Applying job crafting techniques appeared to be particularly effective in mitigating the negative effects of quantitative workload (4/4 significant interactions). By demonstrating that job crafting can also buffer the negative impacts of high job demands on employee well-being, this study contributed to the JD-R model as it suggests that job crafting may even be possible under high work demands, and not only in resourceful jobs, as most previous studies have indicated. In addition to the top-down initiatives for improving employee well-being, bottom-up approaches such as job crafting may also be efficient in preventing burnout and enhancing work engagement.

Expert ratings of job demand and job control as predictors of injury and musculoskeletal disorder risk in a manufacturing cohort

PubMed Central

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

Liberian macroeconomy and simulation of sectoral energy demand: 1981-2000

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hill, L.J.

1984-06-01

The primary purpose of this report is to document the results of a research effort on end-use, sector energy demand in Liberia, West Africa over the 1981-2000 time horizon. The research was undertaken as one component of a much broader integrated energy assessment of Liberia. Other components of the assessment, however, focused on current energy supply and consumption together with future energy supply options for Liberia. This particular report is devoted exclusively to a discussion of Liberian energy demand. The methodology utilized to simulate Liberian sectoral energy demand over the period 1981-2000 involved the recursive interaction of a macroeconomic modelmore » and individual, econometrically-estimated sectoral demand equations. That is, given the projections for gross output in the Liberian economy from the macroeconomic model, sectoral energy demand was simulated. The individual energy demand equations were estimated on the basis of economic variables that are theorized to influence energy consumption in the respective sectors (e.g., price, output). The primary conclusion drawn from the analysis is that, besides being sensitive to changes in international economic activity, the demand for energy in Liberia over the 1981 to 2000 horizon is highly sensitive to internal production of its two primary exports: iron ore and rubber. More specifically, as characterized in the four scenarios, future growth in Liberian energy demand is contingent on the output of three companies: the Liberian American Swedish Mining Company, the Bong Mining Company, and the Firestone Rubber Company. Therefore, expansion of Liberia's energy supply capacity in the future should proceed cautiously. 16 references, 6 figures, 15 tables.« less

Supplier-induced demand: re-examining identification and misspecification in cross-sectional analysis.

PubMed

Peacock, Stuart J; Richardson, Jeffrey R J

2007-09-01

This paper re-examines criticisms of cross-sectional methods used to test for supplier-induced demand (SID) and re-evaluates the empirical evidence using data from Australian medical services. Cross-sectional studies of SID have been criticised on two grounds. First, and most important, the inclusion of the doctor supply in the demand equation leads to an identification problem. This criticism is shown to be invalid, as the doctor supply variable is stochastic and depends upon a variety of other variables including the desirability of the location. Second, cross-sectional studies of SID fail diagnostic tests and produce artefactual findings due to model misspecification. Contrary to this, the re-evaluation of cross-sectional Australian data indicate that demand equations that do not include the doctor supply are misspecified. Empirical evidence from the re-evaluation of Australian medical services data supports the notion of SID. Demand and supply equations are well specified and have very good explanatory power. The demand equation is identified and the desirability of a location is an important predictor of the doctor supply. Results show an average price elasticity of demand of 0.22 and an average elasticity of demand with respect to the doctor supply of 0.46, with the impact of SID becoming stronger as the doctor supply rises. The conclusion we draw from this paper is that two of the main criticisms of the empirical evidence supporting the SID hypothesis have been inappropriately levelled at the methods used. More importantly, SID provides a satisfactory, and robust, explanation of the empirical data on the demand for medical services in Australia.

Association between mental demands at work and cognitive functioning in the general population - results of the health study of the Leipzig research center for civilization diseases (LIFE).

PubMed

Then, Francisca S; Luck, Tobias; Luppa, Melanie; Arélin, Katrin; Schroeter, Matthias L; Engel, Christoph; Löffler, Markus; Thiery, Joachim; Villringer, Arno; Riedel-Heller, Steffi G

2014-01-01

The level of mental demands in the workplace is rising. The present study investigated whether and how mental demands at work are associated with cognitive functioning in the general population. The analysis is based on data of the Health Study of the Leipzig Research Centre for Civilization Disease (LIFE). 2,725 participants aged 40-80 years underwent cognitive testing (Trail-Making Test, Verbal Fluency Test) and provided information on their occupational situation. Participants over the age of 65 years additionally completed the Mini-Mental State Examination. Mental demands at work were rated by a standardized classification system (O*NET). The association between mental demands and cognitive functioning was analyzed using Generalized Linear Modeling (GENLIN) adjusted for age, gender, self-regulation, working hour status, education, and health-related factors. Univariate as well as multivariate analyses demonstrated significant and highly consistent effects of higher mental demands on better performance in cognitive testing. The results also indicated that the effects are independent of education and intelligence. Moreover, analyses of retired individuals implied a significant association between high mental demands at work of the job they once held and a better cognitive functioning in old age. In sum, our findings suggest a significant association between high mental demands at work and better cognitive functioning. In this sense, higher levels of mental demands - as brought about by technological changes in the working environment - may also have beneficial effects for the society as they could increase cognitive capacity levels and might even delay cognitive decline in old age.

Does job burnout mediate negative effects of job demands on mental and physical health in a group of teachers? Testing the energetic process of Job Demands-Resources model.

PubMed

Baka, Łukasz

2015-01-01

The aim of the study was to investigate the direct and indirect - mediated by job burnout - effects of job demands on mental and physical health problems. The Job Demands-Resources model was the theoretical framework of the study. Three job demands were taken into account - interpersonal conflicts at work, organizational constraints and workload. Indicators of mental and physical health problems included depression and physical symptoms, respectively. Three hundred and sixteen Polish teachers from 8 schools participated in the study. The hypotheses were tested with the use of tools measuring job demands (Interpersonal Conflicts at Work, Organizational Constraints, Quantitative Workload), job burnout (the Oldenburg Burnout Inventory), depression (the Beck Hopelessness Scale), and physical symptoms (the Physical Symptoms Inventory). The regression analysis with bootstrapping, using the PROCESS macros of Hayes was applied. The results support the hypotheses partially. The indirect effect and to some extent the direct effect of job demands turned out to be statistically important. The negative impact of 3 job demands on mental (hypothesis 1 - H1) and physical (hypothesis 2 - H2) health were mediated by the increasing job burnout. Only organizational constraints were directly associated with mental (and not physical) health. The results partially support the notion of the Job Demands-Resources model and provide further insight into processes leading to the low well-being of teachers in the workplace. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Latent factor structure of a behavioral economic cigarette demand curve in adolescent smokers

PubMed Central

Bidwell, L. Cinnamon; MacKillop, James; Murphy, James G.; Tidey, Jennifer W.; Colby, Suzanne M.

2012-01-01

Behavioral economic demand curves, or quantitative representations of drug consumption across a range of prices, have been used to assess motivation for a variety of drugs. Such curves generate multiple measures of drug demand that are associated with cigarette consumption and nicotine dependence. However, little is known about the relationships among these facets of demand. The aim of the study was to quantify these relationships in adolescent smokers by using exploratory factor analysis to examine the underlying structure of the facets of nicotine incentive value generated from a demand curve measure. Participants were 138 adolescent smokers who completed a hypothetical cigarette purchase task, which assessed estimated cigarette consumption at escalating levels of price/cigarette. Demand curves and five facets of demand were generated from the measure: Elasticity (i.e., 1/α or proportionate price sensitivity); Intensity (i.e., consumption at zero price); Omax (i.e., maximum financial expenditure on cigarettes); Pmax (i.e., price at which expenditure is maximized); and Breakpoint (i.e., the price that suppresses consumption to zero). Principal components analysis was used to examine the latent structure among the variables. The results revealed a two-factor solution, which were interpreted as “Persistence,” reflecting insensitivity to escalating price, and “Amplitude,” reflecting the absolute levels of consumption and price. These findings suggest a two factor structure of nicotine incentive value as measured via a demand curve. If supported, these findings have implications for understanding the relationships among individual demand indices in future behavioral economic studies and may further contribute to understanding of the nature of cigarette reinforcement. PMID:22727784

Analysis of long-term climate change on per capita water demand in urban versus suburban areas in the Portland metropolitan area, USA

NASA Astrophysics Data System (ADS)

Parandvash, G. Hossein; Chang, Heejun

2016-07-01

We investigated the impacts of long-term climate variability and change on per capita water demand in urban and suburban service areas that have different degrees of development density in the Portland metropolitan area, USA. Together with historical daily weather and water production data, socioeconomic data such as population and unemployment rate were used to estimate daily per capita water demand in the two service areas. The structural time series regression model results show that the sensitivity of per capita water demand to both weather and unemployment rate variables is higher in suburban areas than in urban areas. This is associated with relatively higher proportional demand by the residential sector in the suburban area. The estimated coefficients of the historical demand model were used to project the mid-21st century (2035-2064) per capita water demand under three climate change scenarios that represent high (HadGEM2-ES), medium (MIROC5), and low (GFDL) climate changes. Without climate adaptation, compared to the historical period between 1983 and 2012, per capita water demand is projected to increase by 10.6% in the 2035-2064 period under the HadGEM2-ES in suburban areas, while per capita demand is projected to increase by 4.8% under the same scenario in urban areas. Our findings have implications for future urban water resource management and land use planning in the context of climate variability and change. A tight integration between water resource management and urban planning is needed for preparing for climate adaptation in municipal water planning and management.

Individual and work-unit measures of psychological demands and decision latitude and the use of antihypertensive medication.

PubMed

Daugaard, S; Andersen, J H; Grynderup, M B; Stokholm, Z A; Rugulies, R; Hansen, Å M; Kærgaard, A; Mikkelsen, S; Bonde, J P; Thomsen, J F; Christensen, K L; Kolstad, H A

2015-04-01

To analyse whether psychological demands and decision latitude measured on individual and work-unit level were related to prescription of antihypertensive medication. A total of 3,421 women and 897 men within 388 small work units completed a questionnaire concerning psychological working conditions according to the job strain model. Mean levels of psychological demands and decision latitude were computed for each work unit to obtain exposure measures that were less influenced by reporting bias. Dispensed antihypertensive medication prescriptions were identified in The Danish National Prescription Registry. Odds ratios (OR) comparing the highest and lowest third of the population at individual and work-unit level, respectively, were estimated by multilevel logistic regression adjusted for confounders. Psychological demands and decision latitude were tested for interaction. Supplementary analyses of 21 months follow-up were conducted. Among women, increasing psychological demands at individual (adjusted OR 1.54; 95 % CI 1.02-2.33) and work-unit level (adjusted OR 1.41; 95 % CI 1.04-1.90) was significantly associated with purchase of antihypertensive medication. No significant association was found for decision latitude. Follow-up results supported an association with psychological demands but they were not significant. All results for men showed no association. Psychological demands and decision latitude did not interact. High psychological work demands were associated with the purchase of prescribed antihypertensive medication among women. This effect was present on both the work-unit and the individual level. Among men there were no associations. The lack of interaction between psychological demands and decision latitude did not support the job strain model.

Expected changes in transportation demand in Virginia by 2025.

DOT National Transportation Integrated Search

2003-01-01

To support Virginia's initiatives to design a multimodal transportation plan for the year 2025, this report summarizes how transportation demand is expected to change over the next two decades. Four broad areas affecting transportation demand are exp...

Multimodal network models for robust transportation systems.

DOT National Transportation Integrated Search

2009-10-01

Since transportation infrastructure projects have a lifetime of many decades, project developers must consider : not only the current demand for the project but also the future demand. Future demand is of course uncertain and should : be treated as s...

Forecasting paratransit services demand : review and recommendations - [summary].

DOT National Transportation Integrated Search

2013-01-01

In 2012, the Government Accounting Office reported increasing demand for paratransit services, public transit for those unable to operate a motor vehicle. In Florida, this demand is based on a growing number of people with disabilities or low incomes...

Customer premises services market demand assessment 1980 - 2000: Volume 2

NASA Technical Reports Server (NTRS)

Gamble, R. B.; Saporta, L.; Heidenrich, G. A.

1983-01-01

Potential customer premises service (CPS), telecommunication services, potential CPS user classes, a primary research survey, comparative economics, market demand forcasts, distance distribution of traffic, segmentation of market demand, and a nationwide traffic distribution model are discussed.

Getting the goods without the bads : freight transportation demand management strategies to reduce urban impacts.

DOT National Transportation Integrated Search

2013-09-01

This project identifies and evaluatesstrategies to reduce the social costs associated with goods movement in urban areas by managing : transportation demand. Information about various freight transportation demand management (TDM) strategies was gath...

Demand for abortion and post abortion care in Ibadan, Nigeria.

PubMed

Awoyemi, Bosede O; Novignon, Jacob

2014-01-01

While induced abortion is considered to be illegal and socially unacceptable in Nigeria, it is still practiced by many women in the country. Poor family planning and unsafe abortion practices have daunting effects on maternal health. For instance, Nigeria is on the verge of not meeting the Millennium development goals on maternal health due to high maternal mortality ratio, estimated to be about 630 maternal deaths per 100,000 live births. Recent evidences have shown that a major factor in this trend is the high incidence of abortion in the country. The objective of this paper is, therefore, to investigate the factors determining the demand for abortion and post-abortion care in Ibadan city of Nigeria. The study employed data from a hospital-based/exploratory survey carried out between March to September 2010. Closed ended questionnaires were administered to a sample of 384 women of reproductive age from three hospitals within the Ibadan metropolis in South West Nigeria. However, only 308 valid responses were received and analysed. A probit model was fitted to determine the socioeconomic factors that influence demand for abortion and post-abortion care. The results showed that 62% of respondents demanded for abortion while 52.3% of those that demanded for abortion received post-abortion care. The findings again showed that income was a significant determinant of abortion and post-abortion care demand. Women with higher income were more likely to demand abortion and post-abortion care. Married women were found to be less likely to demand for abortion and post-abortion care. Older women were significantly less likely to demand for abortion and post-abortion care. Mothers' education was only statistically significant in determining abortion demand but not post-abortion care demand. The findings suggest that while abortion is illegal in Nigeria, some women in the Ibadan city do abort unwanted pregnancies. The consequence of this in the absence of proper post-abortion care is daunting. There is the need for policymakers to intensify public education against indiscriminate abortion and to reduce unwanted pregnancies. In effect, there is need for effective alternative family planning methods. This is likely to reduce the demand for abortion. Further, with income found as a major constraint, post abortion services should be made accessible to both the rich and poor alike so as to prevent unnecessary maternal deaths as a result of abortion related complications.

Relationship between the Uncompensated Price Elasticity and the Income Elasticity of Demand under Conditions of Additive Preferences

PubMed Central

Sabatelli, Lorenzo

2016-01-01

Income and price elasticity of demand quantify the responsiveness of markets to changes in income and in prices, respectively. Under the assumptions of utility maximization and preference independence (additive preferences), mathematical relationships between income elasticity values and the uncompensated own and cross price elasticity of demand are here derived using the differential approach to demand analysis. Key parameters are: the elasticity of the marginal utility of income, and the average budget share. The proposed method can be used to forecast the direct and indirect impact of price changes and of financial instruments of policy using available estimates of the income elasticity of demand. PMID:26999511

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

Job demands, burnout, and engagement among nurses: A multi-level analysis of ORCAB data investigating the moderating effect of teamwork

PubMed Central

Montgomery, Anthony; Spânu, Florina; Băban, Adriana; Panagopoulou, Efharis

2015-01-01

According to the Job Demands-Resources (JD-R) model, burnout and engagement are psychological reactions that develop when individual characteristics interact with work characteristics. This study tests the JD-R model using multilevel analysis to test the main and moderating effects of teamwork effectiveness among 1156 nurses in 93 departments from seven European countries. Workload, emotional and organizational demands were positively associated with emotional exhaustion, depersonalization, and negatively with vigor. Emotional and organizational demands were negatively associated with dedication. Teamwork effectiveness was positively associated with engagement. We found no evidence for the moderating effect of teamwork effectiveness in reducing individual perceptions of demands. PMID:26877971

Job demands, burnout, and engagement among nurses: A multi-level analysis of ORCAB data investigating the moderating effect of teamwork.

PubMed

Montgomery, Anthony; Spânu, Florina; Băban, Adriana; Panagopoulou, Efharis

2015-09-01

According to the Job Demands-Resources (JD-R) model, burnout and engagement are psychological reactions that develop when individual characteristics interact with work characteristics. This study tests the JD-R model using multilevel analysis to test the main and moderating effects of teamwork effectiveness among 1156 nurses in 93 departments from seven European countries. Workload, emotional and organizational demands were positively associated with emotional exhaustion, depersonalization, and negatively with vigor. Emotional and organizational demands were negatively associated with dedication. Teamwork effectiveness was positively associated with engagement. We found no evidence for the moderating effect of teamwork effectiveness in reducing individual perceptions of demands.

Saving Power at Peak Hours (LBNL Science at the Theater)

ScienceCinema

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.

How to Estimate Demand Charge Savings from PV on Commercial Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gagnon, Pieter J; Bird, Lori A

Rooftop photovoltaic (PV) systems are compensated through retail electricity tariffs - and for commercial and industrial customers, these are typically comprised of three components: a fixed monthly charge, energy charges, and demand charges. Of these, PV's ability to reduce demand charges has traditionally been the most difficult to estimate. In this fact sheet we explain the basics of demand charges, and provide a new method that a potential customer or PV developer can use to estimate a range of potential demand charge savings for a proposed PV system. These savings can then be added to other project cash flows, inmore » assessing the project's financial performance.« less

Relationship between the Uncompensated Price Elasticity and the Income Elasticity of Demand under Conditions of Additive Preferences.

PubMed

Sabatelli, Lorenzo

2016-01-01

Income and price elasticity of demand quantify the responsiveness of markets to changes in income and in prices, respectively. Under the assumptions of utility maximization and preference independence (additive preferences), mathematical relationships between income elasticity values and the uncompensated own and cross price elasticity of demand are here derived using the differential approach to demand analysis. Key parameters are: the elasticity of the marginal utility of income, and the average budget share. The proposed method can be used to forecast the direct and indirect impact of price changes and of financial instruments of policy using available estimates of the income elasticity of demand.

Solar + Storage Synergies for Managing Commercial-Customer Demand Charges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gagnon, Pieter J.; Govindarajan, Anand; Bird, Lori A.

We study the synergies between behind-the-meter solar and storage in reducing commercial-customer demand charges. This follows two previous studies that examined demand charge savings for stand-alone solar in both the residential and commercial sectors. In this study we show that solar and storage show consistent synergies for demand charge management, that the magnitude of reductions are highly customer-specific, and that the magnitude of savings is influenced by the design of the electricity tariff.

Projections of Demand for Waterborne Transportation, Ohio River Basin, 1980, 1990, 2000, 2020, 2040. Volume 1. Study Summary.

DTIC Science & Technology

1980-12-01

NOTES 3 19. KEY WORDS (Continue on revere side If n.cessary d Identify by block number) Bulk cargo Market demand analysis Commodity resource inventory...The study included a Commodity Resource Inventory, a Modal Split Analysis and a Market Demand Analysis. The work included investigation and analyses...inventory, a modal split analysis and a market demand analysis. The work included investigation and analyses of the production, transportation, and

Job Strain and Self-Reported Insomnia Symptoms among Nurses: What about the Influence of Emotional Demands and Social Support?

PubMed

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.

[Effect of occupational stress on mental health].

PubMed

Yu, Shan-fa; Zhang, Rui; Ma, Liang-qing; Gu, Gui-zhen; Yang, Yan; Li, Kui-rong

2003-02-01

To study the effect of job psychological demands and job control on mental health and their interaction. 93 male freight train dispatchers were evaluated by using revised Job Demand-Control Scale and 7 strain scales. Stepwise regression analysis, Univariate ANOVA, Kruskal-Wallis H and Modian methods were used in statistic analysis. Kruskal-Wallis H and Modian methods analysis revealed the difference in mental health scores among groups of decision latitude (mean rank 55.57, 47.95, 48.42, 33.50, P < 0.05), the differences in scores of mental health (37.45, 40.01, 58.35), job satisfaction (53.18, 46.91, 32.43), daily life strains (33.00, 44.96, 56.12) and depression (36.45, 42.25, 53.61) among groups of job time demands (P < 0.05) were all statistically significant. ANOVA showed that job time demands and decision latitude had interaction effects on physical complains (R(2) = 0.24), state-anxiety (R(2) = 0.26), and daytime fatigue (R(2) = 0.28) (P < 0.05). Regression analysis revealed a significant job time demands and job decision latitude interaction effect as well as significant main effects of the some independent variables on different job strains (R(2) > 0.05). Job time demands and job decision latitude have direct and interactive effects on psychosomatic health, the more time demands, the more psychological strains, the effect of job time demands is greater than that of job decision latitude.

Orthodontic treatment need and demand among 12- and 16 year-old school children in Malaysia.

PubMed

Zreaqat, Maen; Hassan, Rozita; Ismail, Abdul Rashid; Ismail, Noorliza Mastura; Aziz, Fadi Abdul

2013-12-01

Assessment of orthodontic treatment need and demand helps in planning orthodontic services and estimating the required resources and man power. The aim of this study was to assess the orthodontic treatment need and demand and to assess the association between the orthodontic treatment demand and factors such as ITON, gender, and age. Treatment need was assessed using the DHC and AC of IOTN among 12- and 16-year-old Malay school children. The treatment demand was also assessed through a modified health questionnaire and its association with IOTN, age, and gender. A total number of 837 Malay school children were randomly recruited (389 males and 448 females divided into two age groups; 12-year olds; and 16-year olds). Findings showed that 51.4% of 12-year-old school children had definite need for treatment (DHC>4) while 22% of them desired treatment. Among 16-year-old subjects, 56.4% showed definite need for treatment while 47.2% desired treatment. The 16-year-old group was more interested in orthodontic treatment than the 12-year-old group (P<0.001). Only age was associated with treatment demand while gender had no effect (P>0.05). There is a high level of need for treatment among Malay school children which was not associated with orthodontic demand. Age was associated with orthodontic demand.

Convergent evolution of reduced energy demands in extremophile fish

PubMed Central

Arias-Rodriguez, Lenin; Tobler, Michael

2017-01-01

Convergent evolution in organismal function can arise from nonconvergent changes in traits that contribute to that function. Theory predicts that low resource availability and high maintenance costs in extreme environments select for reductions in organismal energy demands, which could be attained through modifications of body size or metabolic rate. We tested for convergence in energy demands and underlying traits by investigating livebearing fish (genus Poecilia) that have repeatedly colonized toxic, hydrogen sulphide-rich springs. We quantified variation in body size and routine metabolism across replicated sulphidic and non-sulphidic populations in nature, modelled total organismal energy demands, and conducted a common-garden experiment to test whether population differences had a genetic basis. Sulphidic populations generally exhibited smaller body sizes and lower routine metabolic rates compared to non-sulphidic populations, which together caused significant reductions in total organismal energy demands in extremophile populations. Although both mechanisms contributed to variation in organismal energy demands, variance partitioning indicated reductions of body size overall had a greater effect than reductions of routine metabolism. Finally, population differences in routine metabolism documented in natural populations were maintained in common-garden reared individuals, indicating evolved differences. In combination with other studies, these results suggest that reductions in energy demands may represent a common theme in adaptation to physiochemical stressors. Selection for reduced energy demand may particularly affect body size, which has implications for life history evolution in extreme environments. PMID:29077740

Global Food Demand Scenarios for the 21st Century

PubMed Central

Biewald, Anne; Weindl, Isabelle; Popp, Alexander; Lotze-Campen, Hermann

2015-01-01

Long-term food demand scenarios are an important tool for studying global food security and for analysing the environmental impacts of agriculture. We provide a simple and transparent method to create scenarios for future plant-based and animal-based calorie demand, using time-dependent regression models between calorie demand and income. The scenarios can be customized to a specific storyline by using different input data for gross domestic product (GDP) and population projections and by assuming different functional forms of the regressions. Our results confirm that total calorie demand increases with income, but we also found a non-income related positive time-trend. The share of animal-based calories is estimated to rise strongly with income for low-income groups. For high income groups, two ambiguous relations between income and the share of animal-based products are consistent with historical data: First, a positive relation with a strong negative time-trend and second a negative relation with a slight negative time-trend. The fits of our regressions are highly significant and our results compare well to other food demand estimates. The method is exemplarily used to construct four food demand scenarios until the year 2100 based on the storylines of the IPCC Special Report on Emissions Scenarios (SRES). We find in all scenarios a strong increase of global food demand until 2050 with an increasing share of animal-based products, especially in developing countries. PMID:26536124

Global Food Demand Scenarios for the 21st Century.

PubMed

Bodirsky, Benjamin Leon; Rolinski, Susanne; Biewald, Anne; Weindl, Isabelle; Popp, Alexander; Lotze-Campen, Hermann

2015-01-01

Long-term food demand scenarios are an important tool for studying global food security and for analysing the environmental impacts of agriculture. We provide a simple and transparent method to create scenarios for future plant-based and animal-based calorie demand, using time-dependent regression models between calorie demand and income. The scenarios can be customized to a specific storyline by using different input data for gross domestic product (GDP) and population projections and by assuming different functional forms of the regressions. Our results confirm that total calorie demand increases with income, but we also found a non-income related positive time-trend. The share of animal-based calories is estimated to rise strongly with income for low-income groups. For high income groups, two ambiguous relations between income and the share of animal-based products are consistent with historical data: First, a positive relation with a strong negative time-trend and second a negative relation with a slight negative time-trend. The fits of our regressions are highly significant and our results compare well to other food demand estimates. The method is exemplarily used to construct four food demand scenarios until the year 2100 based on the storylines of the IPCC Special Report on Emissions Scenarios (SRES). We find in all scenarios a strong increase of global food demand until 2050 with an increasing share of animal-based products, especially in developing countries.

Cosmetic surgery procedures as luxury goods: measuring price and demand in facial plastic surgery.

PubMed

Alsarraf, Ramsey; Alsarraf, Nicole W; Larrabee, Wayne F; Johnson, Calvin M

2002-01-01

To evaluate the relationship between cosmetic facial plastic surgery procedure price and demand, and to test the hypothesis that these procedures function as luxury goods in the marketplace, with an upward-sloping demand curve. Data were derived from a survey that was sent to every (N = 1727) active fellow, member, or associate of the American Academy of Facial Plastic and Reconstructive Surgery, assessing the costs and frequency of 4 common cosmetic facial plastic surgery procedures (face-lift, brow-lift, blepharoplasty, and rhinoplasty) for 1999 and 1989. An economic analysis was performed to assess the relationship of price and demand for these procedures. A significant association was found between increasing surgeons' fees and total charges for cosmetic facial plastic surgery procedures and increasing demand for these procedures, as measured by their annual frequency (P

Could the organ shortage ever be met?

PubMed

Levitt, Mairi

2015-01-01

The organ shortage is commonly presented as having a clear solution, increase the number of organs donated and the problem will be solved. In the light of the Northern Ireland Assembly's consultation on moving to an opt-out organ donor register this article focuses on the social factors and complexities which impact strongly on both the supply of, and demand for, transplantable organs. Judging by the experience of other countries presumed consent systems may or may not increase donations but have not met demand. Donation rates have risen considerably in all parts of the UK recently but there is also an increasing demand for organs. Looking at international donation rates and attitudes, future demand for organs and education on donation, the question is whether the organ shortage could ever be met. The increase in longevity, in rates of diabetes and obesity and in alcohol related liver disease all contribute both to increased demand for transplants, and re-transplants, and a reduction in the number of usable organs. It is unlikely that demand could ever be met, since, if supply was unlimited, the focus would move to financial resources and competing demands on the health care budget in a publicly funded health system. These factors point to the need to focus on ways of reducing, or at least stabilizing, demand where lifestyle factors contribute to the underlying disease.

Job demands-resources predicting burnout and work engagement among Belgian home health care nurses: A cross-sectional study.

PubMed

Vander Elst, Tinne; Cavents, Carolien; Daneels, Katrien; Johannik, Kristien; Baillien, Elfi; Van den Broeck, Anja; Godderis, Lode

A better knowledge of the job aspects that may predict home health care nurses' burnout and work engagement is important in view of stress prevention and health promotion. The Job Demands-Resources model predicts that job demands and resources relate to burnout and work engagement but has not previously been tested in the specific context of home health care nursing. The present study offers a comprehensive test of the Job-Demands Resources model in home health care nursing. We investigate the main and interaction effects of distinctive job demands (workload, emotional demands and aggression) and resources (autonomy, social support and learning opportunities) on burnout and work engagement. Analyses were conducted using cross-sectional data from 675 Belgian home health care nurses, who participated in a voluntary and anonymous survey. The results show that workload and emotional demands were positively associated with burnout, whereas aggression was unrelated to burnout. All job resources were associated with higher levels of work engagement and lower levels of burnout. In addition, social support buffered the positive relationship between workload and burnout. Home health care organizations should invest in dealing with workload and emotional demands and stimulating the job resources under study to reduce the risk of burnout and increase their nurses' work engagement. Copyright © 2016 Elsevier Inc. All rights reserved.

The effects of next-day class characteristics on alcohol demand in college students.

PubMed

Berman, Hanna L; Martinetti, Margaret P

2017-06-01

Behavioral economic principles have been useful for addressing strategies to reduce alcohol consumption among college students. For example, academic variables (such as class schedule or academic rigor) have been found to affect alcohol demand assessed with a hypothetical alcohol purchase task (APT). The present studies used the APT to address the effects of 2 academic variables: next-day course level (no class, introductory level or upper level) and class size (no class, 30-student or 12-student). In each of 2 experiments, undergraduate participants read a description of a drinking context (either a no-class control version or 1 of the academic constraint conditions) and were asked to indicate how many drinks they would purchase at a variety of prices. Hursh and Silberberg's (2008) exponential demand equation was used to determine intensity and elasticity of demand, and Hursh and Roma's (2015) essential value (EV) parameter was calculated to assess essential value. In both experiments, a next-day class reduced alcohol demand, and alcohol consumption decreased as drink price increased. The presence of a smaller next-day class reduced alcohol demand compared with a larger next-day class; however, course level did not differentially affect alcohol demand. These results suggest that smaller next-day classes may reduce alcohol demand among college students and also provide initial evidence for the reliability of EV across studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Is the available cropland and water enough for food demand? A global perspective of the Land-Water-Food nexus

NASA Astrophysics Data System (ADS)

Ibarrola-Rivas, M. J.; Granados-Ramírez, R.; Nonhebel, S.

2017-12-01

Land and water are essential local resources for food production but are limited. The main drivers of increasing food demand are population growth and dietary changes, which depend on the socioeconomic situation of the population. These two factors affect the availability of local resources: population growth reduces the land and water per person; and adoption of affluent diets increases the demand for land and water per person. This study shows potentials of global food supply by linking food demand drivers with national land and water availability. Whether the available land and water is enough to meet national food demand was calculated for 187 countries. The calculations were performed for the past situation (1960 and 2010) and to assess four future scenarios (2050) to discuss different paths of diets, population numbers and agricultural expansion. Inclusion of the demand perspective in the analysis has shown stronger challenges for future global food supply than have other studies. The results show that with the "business as usual" scenario, 40% of the global population in 2050 will live in countries with not enough land nor water to meet the demands of their population. Restriction to basic diets will be the most effective in lowering both land and water constraints. Our results identify both food production and food demand factors, and the regions that may experience the strongest challenges in 2050.

Forecasting domestic water demand in the Haihe river basin under changing environment

NASA Astrophysics Data System (ADS)

Wang, Xiao-Jun; Zhang, Jian-Yun; Shahid, Shamsuddin; Xie, Yu-Xuan; Zhang, Xu

2018-02-01

A statistical model has been developed for forecasting domestic water demand in Haihe river basin of China due to population growth, technological advances and climate change. Historical records of domestic water use, climate, population and urbanization are used for the development of model. An ensemble of seven general circulation models (GCMs) namely, BCC-CSM1-1, BNU-ESM, CNRM-CM5, GISS-E2-R, MIROC-ESM, PI-ESM-LR, MRI-CGCM3 were used for the projection of climate and the changes in water demand in the Haihe River basin under Representative Concentration Pathways (RCPs) 4.5. The results showed that domestic water demand in different sub-basins of the Haihe river basin will gradually increase due to continuous increase of population and rise in temperature. It is projected to increase maximum 136.22 × 108 m3 by GCM BNU-ESM and the minimum 107.25 × 108 m3 by CNRM-CM5 in 2030. In spite of uncertainty in projection, it can be remarked that climate change and population growth would cause increase in water demand and consequently, reduce the gap between water supply and demand, which eventually aggravate the condition of existing water stress in the basin. Water demand management should be emphasized for adaptation to ever increasing water demand and mitigation of the impacts of environmental changes.

Drivers of Change in Managed Water Resources: Modeling the Impacts of Climate and Socioeconomic Changes Using the US Midwest as a Case Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voisin, Nathalie; Leung, Lai-Yung R.; Hejazi, Mohamad I.

A global integrated assessment model including a water-demand model driven by socio-economics, is coupled in a one-way fashion with a land surface hydrology – routing – water resources management model. The integrated modeling framework is applied to the U.S. Upper Midwest (Missouri, Upper Mississippi, and Ohio) to advance understanding of the regional impacts of climate and socio-economic changes on integrated water resources. Implications for future flow regulation, water supply, and supply deficit are investigated using climate change projections with the B1 and A2 emission scenarios, which affect both natural flow and water demand. Changes in water demand are driven bymore » socio-economic factors, energy and food demands, global markets and prices. The framework identifies the multiple spatial scales of interactions between the drivers of changes (natural flow and water demand) and the managed water resources (regulated flow, supply and supply deficit). The contribution of the different drivers of change are quantified regionally, and also evaluated locally, using covariances. The integrated framework shows that water supply deficit is more predictable over the Missouri than the other regions in the Midwest. The predictability of the supply deficit mostly comes from long term changes in water demand although changes in runoff has a greater contribution, comparable to the contribution of changes in demand, over shorter time periods. The integrated framework also shows that spatially, water demand drives local supply deficit. Using elasticity, the sensitivity of supply deficit to drivers of change is established. The supply deficit is found to be more sensitive to changes in runoff than to changes in demand regionally. It contrasts with the covariance analysis that shows that water demand is the dominant driver of supply deficit over the analysed periods. The elasticity indicates the level of mitigation needed to control the demand in order to reduce the vulnerability of the integrated system in future periods. The elasticity analyses also emphasize the need to address uncertainty with respect to changes in natural flow in integrated assessment.« less

Assessing the adequacy of water storage infrastructure capacity under hydroclimatic variability and water demands in the United States

NASA Astrophysics Data System (ADS)

Ho, M. W.; Devineni, N.; Cook, E. R.; Lall, U.

2017-12-01

As populations and associated economic activity in the US evolve, regional demands for water likewise change. For regions dependent on surface water, dams and reservoirs are critical to storing and managing releases of water and regulating the temporal and spatial availability of water in order to meet these demands. Storage capacities typically range from seasonal storage in the east to multi-annual and decadal-scale storage in the drier west. However, most dams in the US were designed with limited knowledge regarding the range, frequency, and persistence of hydroclimatic extremes. Demands for water supplied by these dams have likewise changed. Furthermore, many dams in the US are now reaching or have already exceeded their economic design life. The converging issues of aging dams, improved knowledge of hydroclimatic variability, and evolving demands for dam services result in a pressing need to evaluate existing reservoir capacities with respect to contemporary water demands, long term hydroclimatic variability, and service reliability into the future. Such an effort is possible given the recent development of two datasets that respectively address hydroclimatic variability in the conterminous United States over the past 555 years and human water demand related water stress over the same region. The first data set is a paleoclimate reconstruction of streamflow variability across the CONUS region based on a tree-ring informed reconstruction of the Palmer Drought Severity Index. This streamflow reconstruction suggested that wet spells with shorter drier spells were a key feature of 20th century streamflow compared with the preceding 450 years. The second data set in an annual cumulative drought index that is a measure of water balance based on water supplied through precipitation and water demands based on evaporative demands, agricultural, urban, and industrial demands. This index identified urban and regional hotspots that were particularly dependent on water transfers and vulnerable to persistent drought risk. These data sets are used in conjunction with the national inventory of dams to assess the current capacity of dams to meet water demands considering variability in streamflow over the past 555 years. A case study in the North-East US is presented.

Demand of elderly people for residential care: an exploratory study

PubMed Central

van Bilsen, PMA; Hamers, JPH; Groot, W; Spreeuwenberg, C

2006-01-01

Background Because of the rapid aging population, the demand for residential care exceeds availability. This paper presents the results of a study that focuses on the demand of elderly people for residential care and determinants (elderly people's personal characteristics, needs and resources) that are associated with this demand. Furthermore, the accuracy of the waiting list as a reflection of this demand has been examined. Methods 67 elderly people waiting for admission into a home for the elderly, are subjected to semi-structured interviews. The data are analyzed by using multivariate statistics. Results Elderly people who indicate that they would refuse an offer of admission into a home for the elderly feel healthier (p = 0.02), have greater self-care agency (p = 0.02) and perceive less necessity of admission (p < 0.01), compared to those who would accept such an offer. Especially the inability to manage everyday activities and the lack of a social network are highly associated with the elderly people's demand for residential care. Furthermore, it is evident that waiting lists for homes for the elderly do not accurately reflect the demand for residential care, since 35% of the elderly people on a waiting list did not actually experience an immediate demand for residential care and stated that they would not accept an offer of admission. Quite a lot of respondents just registered out of a sense of precaution; a strategic decision dictated by current shortages in care provision and a vulnerable health status. Conclusion The results contribute to the understanding of waiting lists and the demand for residential care. It became apparent that not everybody who asks for admission into a home for the elderly, really needed it. The importance of elderly people's resources like social networks and the ability to manage everyday activities in relation to the demand for care became clear. These findings are important because they indicate that resources also play a role in predicting elderly people's demand and as a result can guide the development and the (re)design of adequate health care services. PMID:16566822

Exploring the Positive Utility of Travel and Mode Choice

DOT National Transportation Integrated Search

2017-08-01

Why do people travel? Underlying most travel behavior research is the derived-demand paradigm of travel analysis, which assumes that travel demand is derived from the demand for spatially separated activities, traveling is a means to an end (reaching...

Roadway network productivity assessment : system-wide analysis under variant travel demand

DOT National Transportation Integrated Search

2008-11-01

The analysis documented in this report examines the hypothesis that the system-wide productivity of a metropolitan freeway system in peak periods is higher in moderate travel demand conditions than in excessive travel demand conditions. The approach ...

Connected vehicle applications for adaptive overhead lighting (on-demand lighting) : final research report.

DOT National Transportation Integrated Search

2016-07-01

The Virginia Tech Transportation Institute (VTTI) has developed an on-demand roadway lighting : system and has tested the systems effect on driver visual performance. On-demand roadway : lighting can dramatically reduce energy usage while maintain...

Integration of Fixed and Flexible Route Public Transportation Systems, Phase II

DOT National Transportation Integrated Search

2012-01-01

Conventional bus service (with fixed routes and schedules) has lower average cost than flexible bus service (with : demand-responsive routes) at high demand densities. At low demand densities flexible bus service has lower : average costs and provide...

Travel demand modeling for the small and medium sized MPOs in Illinois.

DOT National Transportation Integrated Search

2011-09-01

Travel demand modeling is an important tool in the transportation planning community. It helps forecast travel : characteristics into the future at various planning levels such as state, region and corridor. Using travel demand : modeling to evaluate...

Modeling hurricane evacuation traffic : development of a time-dependent hurricane evacuation demand model.

DOT National Transportation Integrated Search

2006-04-01

Little attention has been given to estimating dynamic travel demand in transportation planning in the past. However, when factors influencing travel are changing significantly over time such as with an approaching hurricane - dynamic demand and t...

Improving the cost effectiveness of financial incentives in managing travel demand management (TDM).

DOT National Transportation Integrated Search

2013-10-01

Providing financial incentives to commuters to use alternative modes is a common element of managing transportation demand. Although these incentives have become common during the past two decades as elements of transportation demand management (TDM)...

23 CFR 450.320 - Congestion management process in transportation management areas.

Code of Federal Regulations, 2010 CFR

2010-04-01

... travel demand reduction and operational management strategies. (b) The development of a congestion... appropriate analysis of reasonable (including multimodal) travel demand reduction and operational management... the analysis demonstrates that travel demand reduction and operational management strategies cannot...

Providing Reliability Services through Demand Response: A Prelimnary Evaluation of the Demand Response Capabilities of Alcoa Inc.

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

Quantifying and Mapping the Supply of and Demand for Carbon Storage and Sequestration Service from Urban Trees

PubMed Central

Zhao, Chang; Sander, Heather A.

2015-01-01

Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration. PMID:26317530

The Use of Artificial Neural Networks for Forecasting the Electric Demand of Stand-Alone Consumers

NASA Astrophysics Data System (ADS)

Ivanin, O. A.; Direktor, L. B.

2018-05-01

The problem of short-term forecasting of electric power demand of stand-alone consumers (small inhabited localities) situated outside centralized power supply areas is considered. The basic approaches to modeling the electric power demand depending on the forecasting time frame and the problems set, as well as the specific features of such modeling, are described. The advantages and disadvantages of the methods used for the short-term forecast of the electric demand are indicated, and difficulties involved in the solution of the problem are outlined. The basic principles of arranging artificial neural networks are set forth; it is also shown that the proposed method is preferable when the input information necessary for prediction is lacking or incomplete. The selection of the parameters that should be included into the list of the input data for modeling the electric power demand of residential areas using artificial neural networks is validated. The structure of a neural network is proposed for solving the problem of modeling the electric power demand of residential areas. The specific features of generation of the training dataset are outlined. The results of test modeling of daily electric demand curves for some settlements of Kamchatka and Yakutia based on known actual electric demand curves are provided. The reliability of the test modeling has been validated. A high value of the deviation of the modeled curve from the reference curve obtained in one of the four reference calculations is explained. The input data and the predicted power demand curves for the rural settlement of Kuokuiskii Nasleg are provided. The power demand curves were modeled for four characteristic days of the year, and they can be used in the future for designing a power supply system for the settlement. To enhance the accuracy of the method, a series of measures based on specific features of a neural network's functioning are proposed.

Information and communication technology demands at work: the association with job strain, effort-reward imbalance and self-rated health in different socio-economic strata.

PubMed

Stadin, Magdalena; Nordin, Maria; Broström, Anders; Magnusson Hanson, Linda L; Westerlund, Hugo; Fransson, Eleonor I

2016-10-01

The use of information and communication technology (ICT) is common in modern working life. ICT demands may give rise to experience of work-related stress. Knowledge about ICT demands in relation to other types of work-related stress and to self-rated health is limited. Consequently, the aim of this study was to examine the association between ICT demands and two types of work-related stress [job strain and effort-reward imbalance (ERI)] and to evaluate the association between these work-related stress measures and self-rated health, in general and in different SES strata. This study is based on cross-sectional data from the Swedish Longitudinal Occupational Survey of Health collected in 2014, from 14,873 gainfully employed people. ICT demands, job strain, ERI and self-rated health were analysed as the main measures. Sex, age, SES, lifestyle factors and BMI were used as covariates. ICT demands correlated significantly with the dimensions of the job strain and ERI models, especially with the demands (r = 0.42; p < 0.01) and effort (r = 0.51; p < 0.01) dimensions. ICT demands were associated with suboptimal self-rated health, also after adjustment for age, sex, SES, lifestyle and BMI (OR 1.49 [95 % CI 1.36-1.63]), but job strain (OR 1.93 [95 % CI 1.74-2.14) and ERI (OR 2.15 [95 % CI 1.95-2.35]) showed somewhat stronger associations with suboptimal self-rated health. ICT demands are common among people with intermediate and high SES and associated with job strain, ERI and suboptimal self-rated health. ICT demands should thus be acknowledged as a potential stressor of work-related stress in modern working life.

Randomized, multicenter study: on-demand versus continuous maintenance treatment with esomeprazole in patients with non-erosive gastroesophageal reflux disease.

PubMed

Bayerdörffer, Ekkehard; Bigard, Marc-Andre; Weiss, Werner; Mearin, Fermín; Rodrigo, Luis; Dominguez Muñoz, Juan Enrique; Grundling, Hennie; Persson, Tore; Svedberg, Lars-Erik; Keeling, Nanna; Eklund, Stefan

2016-04-14

Most patients with gastroesophageal reflux disease experience symptomatic relapse after stopping acid-suppressive medication. The aim of this study was to compare willingness to continue treatment with esomeprazole on-demand versus continuous maintenance therapy for symptom control in patients with non-erosive reflux disease (NERD) after 6 months. This multicenter, open-label, randomized, parallel-group study enrolled adults with NERD who were heartburn-free after 4 weeks' treatment with esomeprazole 20 mg daily. Patients received esomeprazole 20 mg daily continuously or on-demand for 6 months. The primary variable was discontinuation due to unsatisfactory treatment. On-demand treatment was considered non-inferior if the upper limit of the one-sided 95 % confidence interval (CI) for the difference between treatments was <10 %. Of 877 patients enrolled, 598 were randomized to maintenance treatment (continuous: n = 297; on-demand: n = 301). Discontinuation due to unsatisfactory treatment was 6.3 % for on-demand and 9.8 % for continuous treatment (difference -3.5 % [90 % CI: -7.1 %, 0.2 %]). In total, 82.1 and 86.2 % of patients taking on-demand and continuous therapy, respectively, were satisfied with the treatment of heartburn and regurgitation symptoms, a secondary variable (P = NS). Mean study drug consumption was 0.41 and 0.91 tablets/day, respectively. Overall, 5 % of the on-demand group developed reflux esophagitis versus none in the continuous group (P < 0.0001). The Gastrointestinal Symptom Rating Scale Reflux dimension was also improved for continuous versus on-demand treatment. Esomeprazole was well tolerated. In terms of willingness to continue treatment, on-demand treatment with esomeprazole 20 mg was non-inferior to continuous maintenance treatment and reduced medication usage in patients with NERD who had achieved symptom control with initial esomeprazole treatment. ClinicalTrials.gov identifier (NCT number): NCT02670642 ; Date of registration: December 2015.

The clinical endocrinology workforce: current status and future projections of supply and demand.

PubMed

Vigersky, Robert A; Fish, Lisa; Hogan, Paul; Stewart, Andrew; Kutler, Stephanie; Ladenson, Paul W; McDermott, Michael; Hupart, Kenneth H

2014-09-01

Many changes in health care delivery, health legislation, and the physician workforce that affect the supply and demand for endocrinology services have occurred since the first published workforce study of adult endocrinologists in 2003. The objective of the study was to assess the current adult endocrinology workforce data and provide the first analysis of the pediatric endocrinology workforce and to project the supply of and demand for endocrinologists through 2025. A workforce model was developed from an analysis of proprietary and publicly available databases, consultation with a technical expert panel, and the results of an online survey of board-certified endocrinologists. The Endocrine Society commissioned The Lewin Group to estimate current supply and to project gaps between supply and demand for endocrinologists. A technical expert panel of senior endocrinologists provided context, clinical information, and direction. The following were measured: 1) the current adult and pediatric endocrinology workforce and the supply of and demand for endocrinologists through 2025 and 2) the number of additional entrants into the endocrinology work pool that would be required to close the gap between supply and demand. Currently there is a shortage of approximately 1500 adult and 100 pediatric full-time equivalent endocrinologists. The gap for adult endocrinologists will expand to 2700 without an increase in the number of fellows trained. An increase in the prevalence of diabetes mellitus further expands the demand for adult endocrinologists. The gap can be closed in 5 and 10 years by increasing the number of fellowship positions by 14.4% and 5.5% per year, respectively. The gap between supply and demand for pediatric endocrinologists will close by 2016, and thereafter an excess supply over demand will develop at the current rate of new entrants into the work force. There are insufficient adult endocrinologists to satisfy current and future demand. A number of proactive strategies need to be instituted to mitigate this gap.

Assessment of the need for psychosomatic care in patients with suspected cardiac disease.

PubMed

Kunschitz, Evelyn; Friedrich, Oliver; Schöppl, Christine; Weiss, Thomas W; Miehsler, Wolfgang; Sipötz, Johann; Moser, Gabriele

2017-04-01

The study aimed to assess the subjectively perceived need for additional general disease-oriented and psychotherapeutic care in patients with suspected cardiac disease and to investigate if the request for additional care is consistent with impairment of generic quality of life and the presence of psychosomatic risk factors. Patients referred for cardiac stress testing because of suspected cardiac disease completed the assessment of the demand for additional psychological treatment (ADAPT) questionnaire, an assessment tool for counselling demand in patients with chronic illness, the SF-36 quality of life and the hospital anxiety and depression scale (HADS) questionnaires. The questionnaires were administered to 233 patients (age: 54.5 ± 13.4, 57.5 % male). Exclusive demand for disease-oriented counselling was indicated by 45.1 %, demand for psychotherapeutic counselling (exclusive or combined with disease-oriented demand) by 33.9 %. Almost all patients with psychotherapeutic demand (96.3 %) expressed also request for disease-oriented counselling. Patients with exclusive demand for disease-oriented counselling showed significantly lower scores in the emotional and physical functioning and role domains of the SF-36 than the norm population. Patients demanding psychotherapeutic counselling reported significantly lower scores in all SF-36 domains than the norm population. Psychotherapeutic demand was strongly associated with positive indicators for mental distress: SF-36 MH (OR: 4.1), SF-36 MCS (OR: 5.9), HADS anxiety (OR: 3.9), and HADS depression (OR: 3.0). Our study shows that the patients' request for additional care reflects impairment of generic health status and psychological risk load. This indicates that the assessment of subjectively perceived demand allows to screen for patients who are in need of psychosomatic care and motivated to participate in additional counselling and therapy.

Crowd Sourcing Approach for UAS Communication Resource Demand Forecasting

NASA Technical Reports Server (NTRS)

Wargo, Chris A.; Difelici, John; Roy, Aloke; Glaneuski, Jason; Kerczewski, Robert J.

2016-01-01

Congressional attention to Unmanned Aircraft Systems (UAS) has caused the Federal Aviation Administration (FAA) to move the National Airspace System (NAS) Integration project forward, but using guidelines, practices and procedures that are yet to be fully integrated with the FAA Aviation Management System. The real drive for change in the NAS will to come from both UAS operators and the government jointly seeing an accurate forecast of UAS usage demand data. This solid forecast information would truly get the attention of planners. This requires not an aggregate demand, but rather a picture of how the demand is spread across small to large UAS, how it is spread across a wide range of missions, how it is expected over time and where, in terms of geospatial locations, will the demand appear. In 2012 the Volpe Center performed a study of the overall future demand for UAS. This was done by aggregate classes of aircraft types. However, the realistic expected demand will appear in clusters of aircraft activities grouped by similar missions on a smaller geographical footprint and then growing from those small cells. In general, there is not a demand forecast that is tightly coupled to the real purpose of the mission requirements (e.g. in terms of real locations and physical structures such as wind mills to inspect, farms to survey, pipelines to patrol, etc.). Being able to present a solid basis for the demand is crucial to getting the attention of investment, government and other fiscal planners. To this end, Mosaic ATM under NASA guidance is developing a crowd sourced, demand forecast engine that can draw forecast details from commercial and government users and vendors. These forecasts will be vetted by a governance panel and then provide for a sharable accurate set of projection data. Our paper describes the project and the technical approach we are using to design and create access for users to the forecast system.

[Profile of the Emergency demand and influence of televised soccer games on an extra-hospital center in the Tafalla health care district. Navarre, Spain].

PubMed

Pérez-Ciordia, Ignacio; Catalán Fabo, Francisca; Zalacain Nicolay, Fernando; Barriendo Antoñanzas, Maite; Solaegui Diaz de Guereñu, Ramón; Guillén Grima, Francisco

2003-01-01

The demand placed on both hospital as well as extrahospital emergency care units currently continues to increase at a growing rate. This study has a twofold objective: the quantification and study of the personal characteristics of the users who are demanding emergency care and assessing whether televised soccer games have any bearing on the utilization of emergency care services. A longitudinal descriptive study (9,723 users demanding care) and study of cases and controls (1,284 users demanding care) according to whether or not a soccer game was being televised by means of a logistic regression model. The associations were quantified by means of the odds ratio (OR). Those dealt with by telephone or in infirmaries were not included in the study. A total 10.6% of the demand involved home visits, 4.8% of this total having been sent to hospital. A total 13.3% of the demand corresponds to individuals visiting from other healthcare districts, a total of 65 being overusers of emergency care (8 or more visits). The month of August (32.3%). Sundays (44.56%) and the 12:00 p.m.-2:00 p.m. timeframe (8.38%) are the times when the greatest demand for care occurs, the differences being statistically significant. Televised soccer games were associated to a 19.8% (p < 0.001) rise in demand as compared to the control period. A high degree of use of the extrahospital emergency care units has been found to exist, a major part of the demand being concentrated at highly specific points in time. A major degree of care is provided to those visiting from outside their own healthcare districts. Television soccer game broadcasts is associated with the greater utilization of the emergency care services.

How job and family demands impact change in perceived stress: A dyadic study.

PubMed

Smoktunowicz, Ewelina; Cieślak, Roman

2018-01-07

The aim of this two-wave study has been to test the spillover and crossover of job and family demands on changes in perceived stress at work and in the family. Specifically, we proposed that demands from one domain (work or family) spilled over to another domain through interrrole conflict (work-family/family-work conflict) and context-specific self-efficacy. Additionally, we hypothesized that changes in perceived stress were impacted not only by a person's own demands through interrole conflict but also by the demands of one's significant other, in the process of crossover. The study was of dyadic design and it was conducted online, among 130 heterosexual couples, at 2 time points separated by 3 months interval. Hypotheses were verified by means of the path analysis. No support was found for the spillover of job and family demands on changes in perceived stress through interrole conflict and self-efficacy, neither for women nor for men. With regard to the crossover, no support was found for the actor effects, i.e., a person's demands did not impact changes in one's own work- and family-related perceived stress but partial support was found for the partner effects, i.e., women's job demands were associated with men's changes in work and family-related stress through women's work-family conflict, and men's family demands were associated with women's change in family-related perceived stress through men's family-work conflict. The study is a longitudinal test of the Spillover-Crossover model and Work-Home Resources model demonstrating that job and family demands are transmitted across domains and across partners in the intimate relationships through the interrole conflict but the nature of this crossover is different for men and women. Int J Occup Med Environ Health 2018;31(2)199-215. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

The effect of increased consumer demand on fees for aesthetic surgery: an economic analysis.

PubMed

Krieger, L M; Shaw, W W

1999-12-01

Economic theory dictates that changes in consumer demand have predictable effects on prices. Demographics represents an important component of demand for aesthetic surgery. Between the years of 1997 and 2010, the U.S. population is projected to increase by 12 percent. The population increase will be skewed such that those groups undergoing the most aesthetic surgery will see the largest increase. Accounting for the age-specific frequencies of aesthetic surgery and the population increase yields an estimate that the overall market for aesthetic surgery will increase by 19 percent. Barring unforeseen changes in general economic conditions or consumer tastes, demand should increase by an analogous amount. An economic demonstration shows the effects of increasing demand for aesthetic surgery on its fees. Between the years of 1992 and 1997, there was an increase in demand for breast augmentation as fears of associated autoimmune disorders subsided. Similarly, there was increased male acceptance of aesthetic surgery. The number of breast augmentations and procedures to treat male pattern baldness, plastic surgeons, and fees for the procedures were tracked. During the study period, the supply of surgeons and consumer demand increased for both of these procedures. Volume of breast augmentation increased by 275 percent, whereas real fees remained stable. Volume of treatment for male pattern baldness increased by 107 percent, and the fees increased by 29 percent. Ordinarily, an increase in supply leads to a decrease in prices. This did not occur during the study period. Economic analysis demonstrates that the increased supply of surgeons performing breast augmentation was offset by increased consumer demand for the procedure. For this reason, fees were not lowered. Similarly, increased demand for treatment of male pattern baldness more than offset the increased supply of surgeons performing it. The result was higher fees. Emphasis should be placed on using these economic relationships to expand the demand for aesthetic surgery.

Energy demand of the German and Dutch residential building stock under climate change

NASA Astrophysics Data System (ADS)

Olonscheck, Mady; Holsten, Anne; Walther, Carsten; Kropp, Jürgen P.

2014-05-01

In order to mitigate climate change, extraordinary measures are necessary in the future. The building sector, in particular, offers considerable potential for transformation to lower energy demand. On a national level, however, successful and far-reaching measures will likely be taken only if reliable estimates regarding future energy demand from different scenarios are available. The energy demand for space heating and cooling is determined by a combination of behavioral, climatic, constructional, and demographic factors. For two countries, namely Germany and the Netherlands, we analyze the combined effect of future climate and building stock changes as well as renovation measures on the future energy demand for room conditioning of residential buildings until 2060. We show how much the heating energy demand will decrease in the future and answer the question of whether the energy decrease will be exceeded by an increase in cooling energy demand. Based on a sensitivity analysis, we determine those influencing factors with the largest impact on the future energy demand from the building stock. Both countries have national targets regarding the reduction of the energy demand for the future. We provide relevant information concerning the annual renovation rates that are necessary to reach these targets. Retrofitting buildings is a win-win option as it not only helps to mitigate climate change and to lower the dependency on fossil fuels but also transforms the buildings stock into one that is better equipped for extreme temperatures that may occur more frequently with climate change. For the Netherlands, the study concentrates not only on the national, but also the provincial level, which should facilitate directed policy measures. Moreover, the analysis is done on a monthly basis in order to ascertain a deeper understanding of the future seasonal energy demand changes. Our approach constitutes an important first step towards deeper insights into the internal dynamics of the building sector and its climate sensitivity.

Are core self-evaluations a suitable moderator in stressor-detachment relationships? A study among managers' perceived job demands, detachment and strain reactions.

PubMed

Hentrich, Stephan; Zimber, Andreas; Sosnowsky-Waschek, Nadia; Gregersen, Sabine; Petermann, Franz

2018-01-01

The relationships among job demands, personality factors, recovery and psychological health receive increasing attention but are not well understoodOBJECTIVE:Therefore, the present study tests moderating effects among a sample of managers as proposed by the stressor-detachment model. We aimed to determine whether core self-evaluations (CSE) had an influence on the correlations between detachment and strain reactions (depressive symptoms, irritation, exhaustion) and between job demands and detachment. Further, we tested whether detachment attenuates the positive relation between job demands and strain reactions. A convenience sample of managers in three German settings (N = 282) participated in the cross-sectional study. Results based on hierarchical regression analysis showed that high CSE significantly weakened the negative relationship between detachment and depressive symptoms in this sample. However, CSE did not moderate the negative relationship between job demands and detachment. Moreover, results revealed that detachment moderated the positive relation between job demands and exhaustion. The authors tested whether CSE was able to moderate the relationship between job demands, psychological detachment and different stress reactions. Although we found a significant interaction effect, CSE may be too distal to moderate all respective associations.

A Framework for Understanding and Generating Integrated Solutions for Residential Peak Energy Demand

PubMed Central

Buys, Laurie; Vine, Desley; Ledwich, Gerard; Bell, John; Mengersen, Kerrie; Morris, Peter; Lewis, Jim

2015-01-01

Supplying peak energy demand in a cost effective, reliable manner is a critical focus for utilities internationally. Successfully addressing peak energy concerns requires understanding of all the factors that affect electricity demand especially at peak times. This paper is based on past attempts of proposing models designed to aid our understanding of the influences on residential peak energy demand in a systematic and comprehensive way. Our model has been developed through a group model building process as a systems framework of the problem situation to model the complexity within and between systems and indicate how changes in one element might flow on to others. It is comprised of themes (social, technical and change management options) networked together in a way that captures their influence and association with each other and also their influence, association and impact on appliance usage and residential peak energy demand. The real value of the model is in creating awareness, understanding and insight into the complexity of residential peak energy demand and in working with this complexity to identify and integrate the social, technical and change management option themes and their impact on appliance usage and residential energy demand at peak times. PMID:25807384

Managing distrust-induced risk with deposit in supply chain contract decisions.

PubMed

Han, Guanghua; Dong, Ming; Sun, Qi

2014-01-01

This paper studies the trust issue in a two-echelon supply chain information sharing process. In a supply chain, the retailer reports the forecasted demand to the supplier. Traditionally, the supplier's trust in the retailer's reported information is based on the retailer's reputation. However, this paper considers that trust is random and is also affected by the reputation and the demand gap. The supplier and retailer have been shown to have different evaluations regarding the degree of trust. Furthermore, distrust is inherently linked to perceived risk. To mitigate perceived risk, a two-stage decision process with an unpayback deposit contract is proposed. At the first stage, the supplier and the retailer negotiate the deposit contract. At the second stage, a Stackelberg game is used to determine the retailer's reported demand and the supplier's production quantity. We show that the deposits from the retailer's and supplier's perspectives are different. When the retailer's reported demand is equal to the supplier's forecasted demand, the retailer's evaluation of the deposit is more than that of supplier's. When the retailer's reported demand is equal to the retailer's forecasted demand, the deposit from the retailer's perspective is at the lowest level.

Demand forecasting for automotive sector in Malaysia by system dynamics approach

NASA Astrophysics Data System (ADS)

Zulkepli, Jafri; Fong, Chan Hwa; Abidin, Norhaslinda Zainal

2015-12-01

In general, Proton as an automotive company needs to forecast future demand of the car to assist in decision making related to capacity expansion planning. One of the forecasting approaches that based on judgemental or subjective factors is normally used to forecast the demand. As a result, demand could be overstock that eventually will increase the operation cost; or the company will face understock, which resulted losing their customers. Due to automotive industry is very challenging process because of high level of complexity and uncertainty involved in the system, an accurate tool to forecast the future of automotive demand from the modelling perspective is required. Hence, the main objective of this paper is to forecast the demand of automotive Proton car industry in Malaysia using system dynamics approach. Two types of intervention namely optimistic and pessimistic experiments scenarios have been tested to determine the capacity expansion that can prevent the company from overstocking. Finding from this study highlighted that the management needs to expand their production for optimistic scenario, whilst pessimistic give results that would otherwise. Finally, this study could help Proton Edar Sdn. Bhd (PESB) to manage the long-term capacity planning in order to meet the future demand of the Proton cars.

Effects of dynamic-demand-control appliances on the power grid frequency.

PubMed

Tchuisseu, E B Tchawou; Gomila, D; Brunner, D; Colet, P

2017-08-01

Power grid frequency control is a demanding task requiring expensive idle power plants to adapt the supply to the fluctuating demand. An alternative approach is controlling the demand side in such a way that certain appliances modify their operation to adapt to the power availability. This is especially important to achieve a high penetration of renewable energy sources. A number of methods to manage the demand side have been proposed. In this work we focus on dynamic demand control (DDC), where smart appliances can delay their switchings depending on the frequency of the system. We introduce a simple model to study the effects of DDC on the frequency of the power grid. The model includes the power plant equations, a stochastic model for the demand that reproduces, adjusting a single parameter, the statistical properties of frequency fluctuations measured experimentally, and a generic DDC protocol. We find that DDC can reduce small and medium-size fluctuations but it can also increase the probability of observing large frequency peaks due to the necessity of recovering pending task. We also conclude that a deployment of DDC around 30-40% already allows a significant reduction of the fluctuations while keeping the number of pending tasks low.

A framework for understanding and generating integrated solutions for residential peak energy demand.

PubMed

Buys, Laurie; Vine, Desley; Ledwich, Gerard; Bell, John; Mengersen, Kerrie; Morris, Peter; Lewis, Jim

2015-01-01

Supplying peak energy demand in a cost effective, reliable manner is a critical focus for utilities internationally. Successfully addressing peak energy concerns requires understanding of all the factors that affect electricity demand especially at peak times. This paper is based on past attempts of proposing models designed to aid our understanding of the influences on residential peak energy demand in a systematic and comprehensive way. Our model has been developed through a group model building process as a systems framework of the problem situation to model the complexity within and between systems and indicate how changes in one element might flow on to others. It is comprised of themes (social, technical and change management options) networked together in a way that captures their influence and association with each other and also their influence, association and impact on appliance usage and residential peak energy demand. The real value of the model is in creating awareness, understanding and insight into the complexity of residential peak energy demand and in working with this complexity to identify and integrate the social, technical and change management option themes and their impact on appliance usage and residential energy demand at peak times.

Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids.

PubMed

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.

Persistent high job demands and reactivity to mental stress predict future ambulatory blood pressure.

PubMed

Steptoe, A; Cropley, M

2000-05-01

To test the hypothesis that work stress (persistent high job demands over 1 year) in combination with high reactivity to mental stress predict ambulatory blood pressure. Assessment of cardiovascular responses to standardized behavioural tasks, job demands, and ambulatory blood pressure over a working day and evening after 12 months. We studied 81 school teachers (26 men, 55 women), 36 of whom experienced persistent high job demands over 1 year, while 45 reported lower job demands. Participants were divided on the basis of high and low job demands, and high and low systolic pressure reactions to an uncontrollable stress task. Blood pressure and concurrent physical activity were monitored using ambulatory apparatus from 0900 to 2230 h on a working day. Cardiovascular stress reactivity was associated with waist/hip ratio. Systolic and diastolic pressure during the working day were greater in high job demand participants who were stress reactive than in other groups, after adjustment for age, baseline blood pressure, body mass index and negative affectivity. The difference was not accounted for by variations in physical activity. Cardiovascular stress reactivity and sustained psychosocial stress may act in concert to increase cardiovascular risk in susceptible individuals.

Use of mobility aids reduces attentional demand in challenging walking conditions.

PubMed

Miyasike-daSilva, Veronica; Tung, James Y; Zabukovec, Jeanie R; McIlroy, William E

2013-02-01

While mobility aids (e.g., four-wheeled walkers) are designed to facilitate walking and prevent falls in individuals with gait and balance impairments, there is evidence indicating that walkers may increase attentional demands during walking. We propose that walkers may reduce attentional demands under conditions that challenge balance control. This study investigated the effect of walker use on walking performance and attentional demand under a challenged walking condition. Young healthy subjects walked along a straight pathway, or a narrow beam. Attentional demand was assessed with a concurrent voice reaction time (RT) task. Slower RTs, reduced gait speed, and increased number of missteps (>92% of all missteps) were observed during beam-walking. However, walker use reduced attentional demand (faster RTs) and was linked to improved walking performance (increased gait speed, reduced missteps). Data from two healthy older adult cases reveal similar trends. In conclusion, mobility aids can be beneficial by reducing attentional demands and increasing gait stability when balance is challenged. This finding has implications on the potential benefit of mobility aids for persons who rely on walkers to address balance impairments. Copyright © 2012 Elsevier B.V. All rights reserved.

Effects of dynamic-demand-control appliances on the power grid frequency

NASA Astrophysics Data System (ADS)

Tchuisseu, E. B. Tchawou; Gomila, D.; Brunner, D.; Colet, P.

2017-08-01

Power grid frequency control is a demanding task requiring expensive idle power plants to adapt the supply to the fluctuating demand. An alternative approach is controlling the demand side in such a way that certain appliances modify their operation to adapt to the power availability. This is especially important to achieve a high penetration of renewable energy sources. A number of methods to manage the demand side have been proposed. In this work we focus on dynamic demand control (DDC), where smart appliances can delay their switchings depending on the frequency of the system. We introduce a simple model to study the effects of DDC on the frequency of the power grid. The model includes the power plant equations, a stochastic model for the demand that reproduces, adjusting a single parameter, the statistical properties of frequency fluctuations measured experimentally, and a generic DDC protocol. We find that DDC can reduce small and medium-size fluctuations but it can also increase the probability of observing large frequency peaks due to the necessity of recovering pending task. We also conclude that a deployment of DDC around 30-40% already allows a significant reduction of the fluctuations while keeping the number of pending tasks low.

A Small Aircraft Transportation System (SATS) Demand Model

NASA Technical Reports Server (NTRS)

Long, Dou; Lee, David; Johnson, Jesse; Kostiuk, Peter; Yackovetsky, Robert (Technical Monitor)

2001-01-01

The Small Aircraft Transportation System (SATS) demand modeling is a tool that will be useful for decision-makers to analyze SATS demands in both airport and airspace. We constructed a series of models following the general top-down, modular principles in systems engineering. There are three principal models, SATS Airport Demand Model (SATS-ADM), SATS Flight Demand Model (SATS-FDM), and LMINET-SATS. SATS-ADM models SATS operations, by aircraft type, from the forecasts in fleet, configuration and performance, utilization, and traffic mixture. Given the SATS airport operations such as the ones generated by SATS-ADM, SATS-FDM constructs the SATS origin and destination (O&D) traffic flow based on the solution of the gravity model, from which it then generates SATS flights using the Monte Carlo simulation based on the departure time-of-day profile. LMINET-SATS, an extension of LMINET, models SATS demands at airspace and airport by all aircraft operations in US The models use parameters to provide the user with flexibility and ease of use to generate SATS demand for different scenarios. Several case studies are included to illustrate the use of the models, which are useful to identify the need for a new air traffic management system to cope with SATS.

How are changes in exposure to job demands and job resources related to burnout and engagement? A longitudinal study among Chinese nurses and police officers.

PubMed

Hu, Qiao; Schaufeli, Wilmar B; Taris, Toon W

2017-12-01

This study used a person-centered approach to examine the across-time relationships between job demands and job resources on the one hand and employee well-being (burnout and work engagement) on the other. On the basis of the job demands-resources model and conservation of resources (COR) theory, increases in demands and decreases in resources across time were expected to result in unfavorable changes in well-being across time. The results of a 2-wave study among 172 nurses and 273 police officers showed several common patterns across both samples: (a) participants who experienced an increase of demands showed a significant increase in burnout, whereas participants who reported having low resources at both measurement times also showed a significant increase in burnout; (b) participants who experienced decreasing resources reported a significant increase in burnout and a significant decrease in engagement; (c) participants who were exposed to chronic low job resources in a highly demanding environment showed a significant increase in burnout; and (d) participants who were exposed to decreased job resources in a highly demanding environment showed a significant increase in burnout. Copyright © 2017 John Wiley & Sons, Ltd.

Musculoskeletal disorders among workers in plastic manufacturing plants.

PubMed

Fernandes, Rita de Cássia Pereira; Assunção, Ada Avila; Silvany Neto, Annibal Muniz; Carvalho, Fernando Martins

2010-03-01

Epidemiological studies have indicated an association between musculoskeletal disorders (MSDs) and physical work demands. Psychosocial work demands have also been identified as possible risk factors, but findings have been inconsistent. To evaluate factors associated with upper back, neck and upper limb MSD among workers from 14 plastic manufacturing companies located in the city of Salvador, Brazil. A cross-sectional study design was used to survey a stratified proportional random sample of 577 workers. Data were collected by questionnaire interviews. Factor analysis was carried out on 11 physical demands variables. Psychosocial work demands were measured by demand, control and social support questions. The role of socio-demographic factors, lifestyle and household tasks was also examined. Multiple logistic regression was used to identify factors related to upper back, neck and upper limb MSDs. Results from multiple logistic regression showed that distal upper limb MSDs were related to manual handling, work repetitiveness, psychosocial demands, job dissatisfaction, and gender. Neck, shoulder or upper back MSDs were related to manual handling, work repetitiveness, psychosocial demands, job dissatisfaction, and physical unfitness. Reducing the prevalence of musculoskeletal disorders requires: improving the work environment, reducing biomechanical risk factors, and replanning work organization. Programs must also be aware of gender specificities related to MSDs.

Driving forces behind the Chinese public's demand for improved environmental safety.

PubMed

Wen, Ting; Wang, Jigan; Ma, Zongwei; Bi, Jun

2017-12-15

Over the past decades, the public demand for improved environmental safety keeps increasing in China. This study aims to assess the driving forces behind the increasing public demand for improved environmental safety using a provincial and multi-year (1995, 2000, 2005, 2010, and 2014) panel data and the Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model. The potential driving forces investigated included population size, income levels, degrees of urbanization, and educational levels. Results show that population size and educational level are positively (P<0.01) associated with public demand for improved environmental safety. No significant impact on demand was found due to the degree of urbanization. For the impact due to income level, an inverted U-shaped curve effect with the turning point of ~140,000 CNY GDP per capita is indicated. Since per capita GDP of 2015 in China was approximately 50,000 CNY and far from the turning point, the public demand for improved environmental safety will continue rising in the near future. To meet the increasing public demand for improved environmental safety, proactive and risk prevention based environmental management systems coupled with effective environmental risk communication should be established. Copyright © 2017 Elsevier B.V. All rights reserved.

How job demands affect an intimate partner: a test of the spillover-crossover model in Japan.

PubMed

Shimazu, Akihito; Bakker, Arnold B; Demerouti, Evangelia

2009-01-01

The present study examined how job demands affect an intimate partner's well-being. We hypothesized that job demands have a negative influence on partner well-being through the experience of work-family conflict (WFC) and an impaired quality of the relationship (reduced social support and increased social undermining towards the partner). The participants of this study were 99 couples of dual-earner parents in Japan. Consistent with hypotheses, men's job demands (i.e. overload and emotional demands) were positively related to their own reports of WFC, and indirectly to women's ratings of men's WFC. Consequently, women's ratings of men's WFC were negatively related to the quality of the relationship (i.e. decreased social support from and increased social undermining by men), which, in turn, led to women's ill-health (i.e. depressive symptoms and physical complaints). We found similar findings for the model starting with women's job demands; gender did not affect the strength of the relationships in the model. These findings suggest that high job demands initiate a process of work-family conflict and poor relationship quality, which may eventually affect the intimate partner's well-being in an unfavorable way.

Managing Distrust-Induced Risk with Deposit in Supply Chain Contract Decisions

PubMed Central

Han, Guanghua; Dong, Ming; Sun, Qi

2014-01-01

This paper studies the trust issue in a two-echelon supply chain information sharing process. In a supply chain, the retailer reports the forecasted demand to the supplier. Traditionally, the supplier's trust in the retailer's reported information is based on the retailer's reputation. However, this paper considers that trust is random and is also affected by the reputation and the demand gap. The supplier and retailer have been shown to have different evaluations regarding the degree of trust. Furthermore, distrust is inherently linked to perceived risk. To mitigate perceived risk, a two-stage decision process with an unpayback deposit contract is proposed. At the first stage, the supplier and the retailer negotiate the deposit contract. At the second stage, a Stackelberg game is used to determine the retailer's reported demand and the supplier's production quantity. We show that the deposits from the retailer's and supplier's perspectives are different. When the retailer's reported demand is equal to the supplier's forecasted demand, the retailer's evaluation of the deposit is more than that of supplier's. When the retailer's reported demand is equal to the retailer's forecasted demand, the deposit from the retailer's perspective is at the lowest level. PMID:25054190

Modeling taxi demand with GPS data from taxis and transit.

DOT National Transportation Integrated Search

2014-07-01

Identifying factors that influence taxi demand is very important for understanding where and when people use taxis and how taxi demand relates to the availability and quality of transit service. This study used a large set of global positioning syste...

Travel demand forecasting models: a comparison of EMME/2 and QUR II using a real-world network.

DOT National Transportation Integrated Search

2000-10-01

In order to automate the travel demand forecasting process in urban transportation planning, a number of : commercial computer based travel demand forecasting models have been developed, which have provided : transportation planners with powerful and...

EPA'S PHOTOVOLTAIC DEMAND-SIDE MANAGEMENT COST-SHARED DEMONSTRATIONS

EPA Science Inventory

The paper discusses an investigation of how photovoltaics (PV) may be used as both a pollution-mitigating energy replacement for fossil fuels and a demand-side management (DSM) option to reduce peak electrical demands of commercial and residential buildings. leven electric utilit...

U.S. EPA'S PHOTOVOLTAIC DEMAND-SIDE MANAGEMENT PROJECT

EPA Science Inventory

The paper discusses an investigation of how photovoltaic (PV) may be used as both a pollution-mitigating energy replacement for fossil fuels and a demand-side management (DSM) option to reduce peak electrical demands of commercial and residential buildings. leven electric utiliti...

Comparing microscopic activity-based and traditional models of travel demand : an Austin area case study

DOT National Transportation Integrated Search

2007-09-01

Two competing approaches to travel demand modeling exist today. The more traditional 4-step travel demand models rely on aggregate demographic data at a traffic analysis zone (TAZ) level. Activity-based microsimulation methods employ more robus...

Projections of Demand for Waterborne Transportation, Ohio River Basin, 1980, 1990, 2000, 2020, 2040. Volume 10. Group VIII. Iron Ore, Steel and Iron.

DTIC Science & Technology

1980-12-01

SUPPLEMENTARY NOTES 19. KEY WORDS (Continue on reverse aide if neceeary aod identify by block number) Bulk cargo Market demand analysis Iron Commodity resource...shown below. The study included a Commodity Resource Inventory, a Modal Split Analysis and a Market Demand Analysis. The work included investigation...resource inventory, a modal split analysis and a market demand analysis. The work included investigation and analyses of the production

Using Sorties vs. Flying Hours to Predict Aircraft Spares Demand

DTIC Science & Technology

1997-04-01

the war plans, the demand for air- craft spares was substantially less than expected. This expected demand was based on the standard U.S. Air Force...by some combination of them. The Air Force’s new war plans for tactical aircraft in the 1993 USAF War and Mobilization Plan, Volume 5 (WMP-5) have...to continue to use flying hours as the basis for predicting wartime demand from peacetime experience, the cost of the war - time spares requirement

The Impact of Implementing a Demand Forecasting System into a Low-Income Country’s Supply Chain

PubMed Central

Mueller, Leslie E.; Haidari, Leila A.; Wateska, Angela R.; Phillips, Roslyn J.; Schmitz, Michelle M.; Connor, Diana L.; Norman, Bryan A.; Brown, Shawn T.; Welling, Joel S.; Lee, Bruce Y.

2016-01-01

OBJECTIVE To evaluate the potential impact and value of applications (e.g., ordering levels, storage capacity, transportation capacity, distribution frequency) of data from demand forecasting systems implemented in a lower-income country’s vaccine supply chain with different levels of population change to urban areas. MATERIALS AND METHODS Using our software, HERMES, we generated a detailed discrete event simulation model of Niger’s entire vaccine supply chain, including every refrigerator, freezer, transport, personnel, vaccine, cost, and location. We represented the introduction of a demand forecasting system to adjust vaccine ordering that could be implemented with increasing delivery frequencies and/or additions of cold chain equipment (storage and/or transportation) across the supply chain during varying degrees of population movement. RESULTS Implementing demand forecasting system with increased storage and transport frequency increased the number of successfully administered vaccine doses and lowered the logistics cost per dose up to 34%. Implementing demand forecasting system without storage/transport increases actually decreased vaccine availability in certain circumstances. DISCUSSION The potential maximum gains of a demand forecasting system may only be realized if the system is implemented to both augment the supply chain cold storage and transportation. Implementation may have some impact but, in certain circumstances, may hurt delivery. Therefore, implementation of demand forecasting systems with additional storage and transport may be the better approach. Significant decreases in the logistics cost per dose with more administered vaccines support investment in these forecasting systems. CONCLUSION Demand forecasting systems have the potential to greatly improve vaccine demand fulfillment, and decrease logistics cost/dose when implemented with storage and transportation increases direct vaccines. Simulation modeling can demonstrate the potential health and economic benefits of supply chain improvements. PMID:27219341

A forecast of typhoid conjugate vaccine introduction and demand in typhoid endemic low- and middle-income countries to support vaccine introduction policy and decisions.

PubMed

Mogasale, Vittal; Ramani, Enusa; Park, Il Yeon; Lee, Jung Seok

2017-09-02

A Typhoid Conjugate Vaccine (TCV) is expected to acquire WHO prequalification soon, which will pave the way for its use in many low- and middle-income countries where typhoid fever is endemic. Thus it is critical to forecast future vaccine demand to ensure supply meets demand, and to facilitate vaccine policy and introduction planning. We forecasted introduction dates for countries based on specific criteria and estimated vaccine demand by year for defined vaccination strategies in 2 scenarios: rapid vaccine introduction and slow vaccine introduction. In the rapid introduction scenario, we forecasted 17 countries and India introducing TCV in the first 5 y of the vaccine's availability while in the slow introduction scenario we forecasted 4 countries and India introducing TCV in the same time period. If the vaccine is targeting infants in high-risk populations as a routine single dose, the vaccine demand peaks around 40 million doses per year under the rapid introduction scenario. Similarly, if the vaccine is targeting infants in the general population as a routine single dose, the vaccine demand increases to 160 million doses per year under the rapid introduction scenario. The demand forecast projected here is an upper bound estimate of vaccine demand, where actual demand depends on various factors such as country priorities, actual vaccine introduction, vaccination strategies, Gavi financing, costs, and overall product profile. Considering the potential role of TCV in typhoid control globally; manufacturers, policymakers, donors and financing bodies should work together to ensure vaccine access through sufficient production capacity, early WHO prequalification of the vaccine, continued Gavi financing and supportive policy.

Association between mental demands at work and cognitive functioning in the general population – results of the health study of the Leipzig research center for civilization diseases (LIFE)

PubMed Central

2014-01-01

Background The level of mental demands in the workplace is rising. The present study investigated whether and how mental demands at work are associated with cognitive functioning in the general population. Methods The analysis is based on data of the Health Study of the Leipzig Research Centre for Civilization Disease (LIFE). 2,725 participants aged 40–80 years underwent cognitive testing (Trail-Making Test, Verbal Fluency Test) and provided information on their occupational situation. Participants over the age of 65 years additionally completed the Mini-Mental State Examination. Mental demands at work were rated by a standardized classification system (O*NET). The association between mental demands and cognitive functioning was analyzed using Generalized Linear Modeling (GENLIN) adjusted for age, gender, self-regulation, working hour status, education, and health-related factors. Results Univariate as well as multivariate analyses demonstrated significant and highly consistent effects of higher mental demands on better performance in cognitive testing. The results also indicated that the effects are independent of education and intelligence. Moreover, analyses of retired individuals implied a significant association between high mental demands at work of the job they once held and a better cognitive functioning in old age. Conclusions In sum, our findings suggest a significant association between high mental demands at work and better cognitive functioning. In this sense, higher levels of mental demands – as brought about by technological changes in the working environment – may also have beneficial effects for the society as they could increase cognitive capacity levels and might even delay cognitive decline in old age. PMID:24914403

A forecast of typhoid conjugate vaccine introduction and demand in typhoid endemic low- and middle-income countries to support vaccine introduction policy and decisions

PubMed Central

Ramani, Enusa; Park, Il Yeon; Lee, Jung Seok

2017-01-01

ABSTRACT A Typhoid Conjugate Vaccine (TCV) is expected to acquire WHO prequalification soon, which will pave the way for its use in many low- and middle-income countries where typhoid fever is endemic. Thus it is critical to forecast future vaccine demand to ensure supply meets demand, and to facilitate vaccine policy and introduction planning. We forecasted introduction dates for countries based on specific criteria and estimated vaccine demand by year for defined vaccination strategies in 2 scenarios: rapid vaccine introduction and slow vaccine introduction. In the rapid introduction scenario, we forecasted 17 countries and India introducing TCV in the first 5 y of the vaccine's availability while in the slow introduction scenario we forecasted 4 countries and India introducing TCV in the same time period. If the vaccine is targeting infants in high-risk populations as a routine single dose, the vaccine demand peaks around 40 million doses per year under the rapid introduction scenario. Similarly, if the vaccine is targeting infants in the general population as a routine single dose, the vaccine demand increases to 160 million doses per year under the rapid introduction scenario. The demand forecast projected here is an upper bound estimate of vaccine demand, where actual demand depends on various factors such as country priorities, actual vaccine introduction, vaccination strategies, Gavi financing, costs, and overall product profile. Considering the potential role of TCV in typhoid control globally; manufacturers, policymakers, donors and financing bodies should work together to ensure vaccine access through sufficient production capacity, early WHO prequalification of the vaccine, continued Gavi financing and supportive policy. PMID:28604164

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.

Do psychosocial work conditions predict risk of disability pensioning? An analysis of register-based outcomes using pooled data on 40,554 observations.

PubMed

Clausen, Thomas; Burr, Hermann; Borg, Vilhelm

2014-06-01

To investigate whether high psychosocial job demands (quantitative demands and work pace) and low psychosocial job resources (influence at work and quality of leadership) predicted risk of disability pensioning among employees in four occupational groups--employees working with customers, employees working with clients, office workers and manual workers--in line with the propositions of the Job Demands-Resources (JD-R) model. Survey data from 40,554 individuals were fitted to the DREAM register containing information on payments of disability pension. Using multi-adjusted Cox regression, observations were followed in the DREAM-register to assess risk of disability pensioning. Average follow-up time was 5.9 years (SD=3.0). Low levels of influence at work predicted an increased risk of disability pensioning and medium levels of quantitative demands predicted a decreased risk of disability pensioning in the study population. We found significant interaction effects between job demands and job resources as combinations low quality of leadership and high job demands predicted the highest rate of disability pensioning. Further analyses showed some, but no statistically significant, differences between the four occupational groups in the associations between job demands, job resources and risk of disability pensioning. The study showed that psychosocial job demands and job resources predicted risk of disability pensioning. The direction of some of the observed associations countered the expectations of the JD-R model and the findings of the present study therefore imply that associations between job demands, job resources and adverse labour market outcomes are more complex than conceptualised in the JD-R model. © 2014 the Nordic Societies of Public Health.

Agricultural Groundwater Demands in the Conterminous United States

NASA Astrophysics Data System (ADS)

Ho, M. W.; Parthasarathy, V.; Etienne, E.; Russo, T. A.; Devineni, N.; Lall, U.

2016-12-01

In the conterminous United States (CONUS), over 40% of water consumed for irrigation, livestock and domestic water is sourced from groundwater. The late 20th century and 21st century saw an expansion in irrigated agriculture across the CONUS that was accompanied by increased pumping of groundwater. Groundwater is typically used to mitigate impacts of drought on surface water supplies enabling water demands to be met as well as to augment sparse surface water resources in arid regions or where surface water availability is highly variable temporally and/or spatially. A Demand Sensitive Drought Index (DSDI) is used to examine the impacts of agricultural water needs on groundwater in the CONUS. The DSDI accounts for agricultural water deficits driven by low precipitation, high agricultural water demand, or a combination of both. Changes in groundwater levels relative to agricultural water deficits are characterized relative to precipitation during the growing season and winter precipitation. In several key irrigated agricultural regions in the CONUS, long-term trends in groundwater levels appear to reflect prolonged periods of surface water deficits resulting from land use and associated unsustainable water demands. These areas are subsequent unable to recover from persistent states of agricultural drought. Conversely, reductions in agricultural water demands for crops do not necessarily lead to immediate recovery of groundwater levels due to the demand for groundwater in other sectors. Calls to establish or reform groundwater policies have recently been made in an effort to achieve holistic groundwater management strategies that consider the human demands on both surface water and groundwater. There is a need for relevant groundwater policies to ensure that water demands are adequately managed across sectors without unsustainably depleting groundwater resources and to ensure efficient economic activity.

Job demands, job resources and long-term sickness absence in the Danish eldercare services: a prospective analysis of register-based outcomes.

PubMed

Clausen, Thomas; Nielsen, Karina; Carneiro, Isabella Gomes; Borg, Vilhelm

2012-01-01

To investigate associations between psychosocial job demands, job resources and cases of registered long-term sickness absence among nursing staff in the eldercare services. Research has shown that psychosocial work environment exposures predict sickness absence in healthcare settings. However, only few studies have longitudinally investigated associations between specific job demands and job resources and risk of long-term sickness absence. Questionnaire data were collected in 2004 and 2005 among all employees in the eldercare services in 35 Danish municipalities and were followed in a National register on payment of sickness absence compensation for a 1-year follow-up period (N = 7921). Three psychosocial job demands - emotional demands, quantitative demands and role conflicts - and three job resources - influence, quality of leadership and team climate - were investigated to predict risk of sickness absence for eight or more consecutive weeks in the follow-up period. Data were analysed using Cox proportional hazards model. A percentage of 6·5 of the respondents were absent for eight or more consecutive weeks during follow-up. The analyses showed that emotional demands, role conflicts, influence, quality of leadership and team climate were significantly associated with risk of long-term sickness absence. In an analysis with mutual adjustment for all job demands and job resources, influence constituted the strongest predictor of long-term sickness absence (negative association). Job demands and job resources are significantly associated with risk of long-term sickness absence. Interventions aimed at improving the psychosocial work environment may, therefore, contribute towards preventing long-term sickness absence in the eldercare services. © 2011 Blackwell Publishing Ltd.

Expert ratings of job demand and job control as predictors of injury and musculoskeletal disorder risk in a manufacturing cohort.

PubMed

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/

Estimating future dental services' demand and supply: a model for Northern Germany.

PubMed

Jäger, Ralf; van den Berg, Neeltje; Hoffmann, Wolfgang; Jordan, Rainer A; Schwendicke, Falk

2016-04-01

To plan dental services, a spatial estimation of future demands and supply is required. We aimed at estimating demand and supply in 2030 in Northern Germany based on the expected local socio-demography and oral-health-related morbidity, and the predicted number of dentists and their working time. All analyses were performed on zip-code level. Register data were used to determine the number of retiring dentists and to construct regression models for estimating the number of dentists moving into each zip-code area until 2030. Demand was modelled using projected demography and morbidities. Demand-supply ratios were evaluated and spatial analyses applied. Sensitivity analyses were employed to assess robustness of our findings. Compared with 2011, the population decreased (-7% to -11%) and aged (from mean 46 to 51 years) until 2030. Oral-health-related morbidity changed, leading to more periodontal and fewer prosthetic treatments needs, with the overall demand decreasing in all scenarios (-25% to -33%). In contrast, the overall number of dentists did only limitedly change, resulting in moderate decrease in the supplied service quantities (max. -22%). Thus, the demand-supply ratio increased in all but the worst case scenario, but was unequally distributed between spatial units, with several areas being over- and some being under- or none-serviced in 2030. Within the limitations of the underlying data and the required assumptions, this study expects an increasingly polarized ratio of dental services demand and supply in Northern Germany. Our estimation allows to assess the impact of different influence factors on demand or supply and to specifically identify potential challenges for workforce planning and regulation in different spatial units. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mental and physical health-related functioning mediates between psychological job demands and sickness absence among nurses.

PubMed

Roelen, Corné; van Rhenen, Willem; Schaufeli, Wilmar; van der Klink, Jac; Magerøy, Nils; Moen, Bente; Bjorvatn, Bjørn; Pallesen, Ståle

2014-08-01

To investigate whether health-related functioning mediates the effect of psychological job demands on sickness absence in nurses. Nurses face high job demands that can have adverse health effects resulting in sickness absence. Prospective cohort study with 1-year follow-up. Data for 2964 Norwegian nurses were collected in the period 2008-2010. At baseline, psychological job demands were measured with the Demand-Control-Support Questionnaire. Health-related functioning was assessed by the Mental Composite Score and the Physical Composite Score of the SF-12 Health Survey (2nd version). Sickness absence (no = 0, yes = 1) was self-reported at 1-year follow-up. Interaction and mediation analyses were conducted stratified by tenure (<1-year, 1-2 years, 3-6 years, >6 years) as a registered nurse. A total of 2180 nurses (74%) with complete data were eligible for analysis. A significant three-way interaction between job demands, control and support was found in newly licensed nurses (tenure <1-year). Baseline psychological job demands were positively associated with sickness absence at 1-year follow-up. This association was substantially weakened when Mental Composite Score and Physical Composite Score were introduced as mediator variables, indicating a partial mediation effect that was particularly pronounced in newly licensed nurses. Psychological job demands did not modify the effect of health-related functioning on sickness absence. Both mental and physical health-related functioning mediated between psychological job demands and sickness absence. Nurse managers should pay attention to health-related functioning, because poor health-related functioning may predict sickness absence, especially in newly licensed nurses. © 2013 John Wiley & Sons Ltd.

The demand control model and circadian saliva cortisol variations in a Swedish population based sample (The PART study)

PubMed Central

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

Rimonabant reduces the essential value of food in the genetically obese Zucker rat: an exponential demand analysis.

PubMed

Rasmussen, Erin B; Reilly, William; Buckley, Jessica; Boomhower, Steven R

2012-02-01

Research on free-food intake suggests that cannabinoids are implicated in the regulation of feeding. Few studies, however, have characterized how environmental factors that affect food procurement interact with cannabinoid drugs that reduce food intake. Demand analysis provides a framework to understand how cannabinoid blockers, such as rimonabant, interact with effort in reducing demand for food. The present study examined the effects rimonabant had on demand for sucrose in obese Zucker rats when effort to obtain food varied and characterized the data using the exponential ("essential value") model of demand. Twenty-nine male (15 lean, 14 obese) Zucker rats lever-pressed under eight fixed ratio (FR) schedules of sucrose reinforcement, in which the number of lever-presses to gain access to a single sucrose pellet varied between 1 and 300. After behavior stabilized under each FR schedule, acute doses of rimonabant (1-10mg/kg) were administered prior to some sessions. The number of food reinforcers and responses in each condition was averaged and the exponential and linear demand equations were fit to the data. These demand equations quantify the value of a reinforcer by its sensitivity to price (FR) increases. Under vehicle conditions, obese Zucker rats consumed more sucrose pellets than leans at smaller fixed ratios; however, they were equally sensitive to price increases with both models of demand. Rimonabant dose-dependently reduced reinforcers and responses for lean and obese rats across all FR schedules. Data from the exponential analysis suggest that rimonabant dose-dependently increased elasticity, i.e., reduced the essential value of sucrose, a finding that is consistent with graphical depictions of normalized demand curves. Copyright © 2011 Elsevier Inc. All rights reserved.

Testing and extending the triple match principle in the nursing profession: a generational perspective on job demands, job resources and strain at work.

PubMed

Lavoie-Tremblay, Melanie; Trépanier, Sarah-Geneviève; Fernet, Claude; Bonneville-Roussy, Arielle

2014-02-01

The Triple Match Principle offers insight into the interactive interplay between job demands and job resources in the prediction of work-related strain. The aim of this article was to examine the interplay among job demands, job resources and strain in the nursing profession (the Triple Match Principle) and to gain insight into potential generational differences by investigating generation as a moderator of that interplay. No research has been done to evaluate generational differences in the Triple Match Principle. In a context of nursing shortages, it seems important to examine the relevance of the Triple Match Principle with respect to different generations of nurses. Cross-sectional study. A total of 1254 public healthcare sector nurses in Quebec, Canada, completed a questionnaire in the autumn of 2010. The questionnaire was used to assess cognitive, emotional and physical job demands and resources; psychological distress; psychosomatic complaints; and turnover intention. The results supported the Triple Match Principle and showed that job resources were more likely to buffer the effect of job demands on strain as the degree of match in qualitative dimension among demands, resources and strain increased (33·3% of triple-match interactions, 22·22% of double-match interactions and 16·67% non-match interactions were significant). Moreover, generation played a key role in this interplay, as it increased the number of significant qualitative interactions among job demands, job resources and strain. The results underscore the necessity of providing adequate job resources tailored to the specific job demands nurses face, to counteract the negative effects of those demands. © 2013 John Wiley & Sons Ltd.

Emotional job demands and the role of matching job resources: a cross-sectional survey study among health care workers.

PubMed

de Jonge, Jan; Le Blanc, Pascale M; Peeters, Maria C W; Noordam, Hanneke

2008-10-01

Research on emotional labour in health care work has not yet revealed under what conditions emotional job demands have an impact on employee health and well-being. There is a need for more theory to unveil the black box of emotional labour processes. To test the moderating role of matching (i.e. emotional) and non-matching (i.e. cognitive) job resources in the relation between emotional job demands and employee health/well-being (i.e. emotional exhaustion, employee creativity, and work motivation). A cross-sectional survey with anonymous questionnaires was conducted. A large organization for residential elderly care with eight locations in an urban area in the Netherlands. Questionnaires were distributed to 1259 health care workers, of which 826 people returned the questionnaire (66% response rate). In addition to descriptive statistics, multivariate multiple regression analysis (LISREL 8.54) with cross-validation was conducted. Findings showed that emotional job resources moderated the relation between emotional job demands and health/well-being outcomes. Firstly, emotional job resources were able to moderate the relation between emotional job demands and emotional exhaustion. Secondly, both emotional job resources and, to a lesser extent, cognitive job resources were able to moderate the relation between emotional job demands and positive well-being outcomes (i.e. employee creativity and work motivation). Finally, cross-validation showed that parameter estimates did not vary across subsamples. Job resources could compensate for resources lost through meeting the requirements of emotional job demands, thereby reducing stress-reactions and increasing well-being. Providing health care workers with more, preferably matching, job resources could make emotional job demands less stressful, and even stimulating and challenging. Future longitudinal studies should investigate the interplay of emotional job demands and (matching) job resources more profoundly.

Latent factor structure of a behavioral economic cigarette demand curve in adolescent smokers.

PubMed

Bidwell, L Cinnamon; MacKillop, James; Murphy, James G; Tidey, Jennifer W; Colby, Suzanne M

2012-11-01

Behavioral economic demand curves, or quantitative representations of drug consumption across a range of prices, have been used to assess motivation for a variety of drugs. Such curves generate multiple measures of drug demand that are associated with cigarette consumption and nicotine dependence. However, little is known about the relationships among these facets of demand. The aim of the study was to quantify these relationships in adolescent smokers by using exploratory factor analysis to examine the underlying structure of the facets of nicotine incentive value generated from a demand curve measure. Participants were 138 adolescent smokers who completed a hypothetical cigarette purchase task, which assessed estimated cigarette consumption at escalating levels of price/cigarette. Demand curves and five facets of demand were generated from the measure: Elasticity (i.e., 1/α or proportionate price sensitivity); Intensity (i.e., consumption at zero price); O(max) (i.e., maximum financial expenditure on cigarettes); P(max) (i.e., price at which expenditure is maximized); and Breakpoint (i.e., the price that suppresses consumption to zero). Principal components analysis was used to examine the latent structure among the variables. The results revealed a two-factor solution, which were interpreted as "Persistence," reflecting insensitivity to escalating price, and "Amplitude," reflecting the absolute levels of consumption and price. These findings suggest a two factor structure of nicotine incentive value as measured via a demand curve. If supported, these findings have implications for understanding the relationships among individual demand indices in future behavioral economic studies and may further contribute to understanding of the nature of cigarette reinforcement. Copyright © 2012 Elsevier Ltd. All rights reserved.

The impact of implementing a demand forecasting system into a low-income country's supply chain.

PubMed

Mueller, Leslie E; Haidari, Leila A; Wateska, Angela R; Phillips, Roslyn J; Schmitz, Michelle M; Connor, Diana L; Norman, Bryan A; Brown, Shawn T; Welling, Joel S; Lee, Bruce Y

2016-07-12

To evaluate the potential impact and value of applications (e.g. adjusting ordering levels, storage capacity, transportation capacity, distribution frequency) of data from demand forecasting systems implemented in a lower-income country's vaccine supply chain with different levels of population change to urban areas. Using our software, HERMES, we generated a detailed discrete event simulation model of Niger's entire vaccine supply chain, including every refrigerator, freezer, transport, personnel, vaccine, cost, and location. We represented the introduction of a demand forecasting system to adjust vaccine ordering that could be implemented with increasing delivery frequencies and/or additions of cold chain equipment (storage and/or transportation) across the supply chain during varying degrees of population movement. Implementing demand forecasting system with increased storage and transport frequency increased the number of successfully administered vaccine doses and lowered the logistics cost per dose up to 34%. Implementing demand forecasting system without storage/transport increases actually decreased vaccine availability in certain circumstances. The potential maximum gains of a demand forecasting system may only be realized if the system is implemented to both augment the supply chain cold storage and transportation. Implementation may have some impact but, in certain circumstances, may hurt delivery. Therefore, implementation of demand forecasting systems with additional storage and transport may be the better approach. Significant decreases in the logistics cost per dose with more administered vaccines support investment in these forecasting systems. Demand forecasting systems have the potential to greatly improve vaccine demand fulfilment, and decrease logistics cost/dose when implemented with storage and transportation increases. Simulation modeling can demonstrate the potential health and economic benefits of supply chain improvements. Copyright © 2016 Elsevier Ltd. All rights reserved.

Projecting Future Scheduled Airline Demand, Schedules and NGATS Benefits Using TSAM

NASA Technical Reports Server (NTRS)

Dollyhigh, Samuel; Smith, Jeremy; Viken, Jeff; Trani, Antonio; Baik, Hojong; Hinze, Nickolas; Ashiabor, Senanu

2006-01-01

The Transportation Systems Analysis Model (TSAM) developed by Virginia Tech s Air Transportation Systems Lab and NASA Langley can provide detailed analysis of the effects on the demand for air travel of a full range of NASA and FAA aviation projects. TSAM has been used to project the passenger demand for very light jet (VLJ) air taxi service, scheduled airline demand growth and future schedules, Next Generation Air Transportation System (NGATS) benefits, and future passenger revenues for the Airport and Airway Trust Fund. TSAM can project the resulting demand when new vehicles and/or technology is inserted into the long distance (100 or more miles one-way) transportation system, as well as, changes in demand as a result of fare yield increases or decreases, airport transit times, scheduled flight times, ticket taxes, reductions or increases in flight delays, and so on. TSAM models all long distance travel in the contiguous U.S. and determines the mode choice of the traveler based on detailed trip costs, travel time, schedule frequency, purpose of the trip (business or non-business), and household income level of the traveler. Demand is modeled at the county level, with an airport choice module providing up to three airports as part of the mode choice. Future enplanements at airports can be projected for different scenarios. A Fratar algorithm and a schedule generator are applied to generate future flight schedules. This paper presents the application of TSAM to modeling future scheduled air passenger demand and resulting airline schedules, the impact of NGATS goals and objectives on passenger demand, along with projections for passenger fee receipts for several scenarios for the FAA Airport and Airway Trust Fund.

Attentional demands and postural recovery: the effects of aging.

PubMed

Brown, L A; Shumway-Cook, A; Woollacott, M H

1999-04-01

Cognitive demands associated with balance and locomotion may contribute to the incidence of falling among older adults. This study addressed issues related to the effects of aging on the attentional demands of recovering from an external disturbance to balance. This research also investigated whether performing a secondary cognitive task differentially affects postural recovery in young versus older adults. Fifteen young and 10 healthy older adults were exposed to a series of balance disturbances. Attentional demands were assessed using a dual task paradigm where postural recovery served as the primary task, and counting backwards served as a concurrent secondary cognitive task. The effect of the counting task was assessed by comparing kinematic variables related to feet-in-place and stepping recovery strategies. Recovering upright stance was found to be attentionally demanding in both age groups. The type of recovery strategy did not influence attentional demands in young adults; however, a hierarchy of increasing attentional demands between the ankle strategy and compensatory stepping was apparent among older adults. In addition, stepping appears to be more attentionally demanding for older adults than for younger adults. Counting backwards did not affect the type of strategy used; however, it did affect the kinematics of stepping. For both age groups, steps occurred when the center of mass was located in a more central location within the base of support when the secondary task was added. The ability to recover a stable posture following an external perturbation is more attentionally demanding for older adults than for younger adults. This would suggest that for some older adults, an increased risk for loss of balance and falls may result if sufficient attentional resources are not allocated to the task of postural recovery.

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

Life on the line: Job demands, perceived co-worker support for safety, and hazardous work events.

PubMed

Turner, Nick; Chmiel, Nik; Hershcovis, M Sandy; Walls, Melanie

2010-10-01

The present study of 334 United Kingdom trackside workers tested an interaction hypothesis. We hypothesized, drawing on the job demands-resources framework, that perceived support for safety (from senior managers, supervisors, and coworkers) as job resources would weaken the relationship between higher job demands and more frequent hazardous work events. Consistent with social impact theory, we predicted that perceived coworker support for safety would be particularly influential when trackside workers faced higher job demands. Moderated multiple regression showed that, of all three sources of perceived support for safety, perceived coworker support for safety was most important for keeping employees safe in the face of high job demands. © 2010 APA, all rights reserved.

Models for forecasting energy use in the US farm sector

NASA Astrophysics Data System (ADS)

Christensen, L. R.

1981-07-01

Econometric models were developed and estimated for the purpose of forecasting electricity and petroleum demand in US agriculture. A structural approach is pursued which takes account of the fact that the quantity demanded of any one input is a decision made in conjunction with other input decisions. Three different functional forms of varying degrees of complexity are specified for the structural cost function, which describes the cost of production as a function of the level of output and factor prices. Demand for materials (all purchased inputs) is derived from these models. A separate model which break this demand up into demand for the four components of materials is used to produce forecasts of electricity and petroleum is a stepwise manner.

Certificates of confidentiality: legal counsels' experiences with and perspectives on legal demands for research data.

PubMed

Wolf, Leslie E; Dame, Lauren A; Patel, Mayank J; Williams, Brett A; Austin, Jefferey A; Beskow, Laura M

2012-10-01

The certificate of confidentiality (Certificate) is an important tool for protecting identifiable, sensitive human subjects research data in the United States. However, little is known about the Certificate's effectiveness in protecting identifiable data. We interviewed 24 legal counsel representing U.S. research institutions about their experiences with legal demands for research data. Our respondents reported few, if any, legal demands over the course of their tenure, but two-thirds had experience with legal demands for data protected by a Certificate. They reported such demands often were resolved without disclosure of identifiable research data, typically without court intervention. While our respondents reported similar success protecting identifiable data in court, they often did not rely on the Certificate to do so.

Analysing the Effect of Demand Uncertainty in Dynamic Pricing with EAs

NASA Astrophysics Data System (ADS)

Shakya, Siddhartha; Oliveira, Fernando; Owusu, Gilbert

Dynamic pricing is a pricing strategy where a firm adjust the price for their products and services as a function of its perceived demand at different times. In this paper, we show how Evolutionary algorithms (EA) can be used to analyse the effect of demand uncertainty in dynamic pricing. The experiments are conducted in a range of dynamic pricing problems considering a number of different stochastic scenarios with a number of different EAs. The results are analysed, which suggest that higher demand fluctuation may not have adverse effect to the profit in comparison to the lower demand fluctuation, and that the reliability of EA for finding accurate policy could be higher when there is higher fluctuation then when there is lower fluctuation.

[Influence factors on supply and demand changes in the field of acupuncture and moxibustion].

PubMed

Liu, Bin; Li, Ping

2011-11-01

Based on principles of health economy and the present situation, the possibility and regularity on changes in the supply and demand field of acupuncture and moxibustion through various viewpoints were analyzed, which included demand and supply elasticity of acup-mox services to market price and the relevant factors, categories and nature of acup-mox services, business idea of supplier on the strength of marginal cost and marginal benefit, expenditure level and inclination of demander, complementary and substitutive treatment of acup-mox therapy, and the relevant time and geographic factors to change in quantity demand and supply. Therefore, it could be applied as reference to redaction and reform of the relevant health economics policy by health administrative management.

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

Analyzing the impacts of final demand changes on total output using input-output approach: The case of Japanese ICT sectors

NASA Astrophysics Data System (ADS)

Zuhdi, Ubaidillah

2014-03-01

The purpose of this study is to analyze the impacts of final demand changes on total output of Japanese Information and Communication Technologies (ICT) sectors in future time. This study employs one of analysis tool in Input-Output (IO) analysis, demand-pull IO quantity model, in achieving the purpose. There are three final demand changes used in this study, namely (1) export, (2) import, and (3) outside households consumption changes. This study focuses on "pure change" condition, the condition that final demand changes only appear in analyzed sectors. The results show that export and outside households consumption modifications give positive impact while opposite impact could be seen in import change.