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.
Co-optimization of Energy and Demand-Side Reserves in Day-Ahead Electricity Markets
NASA Astrophysics Data System (ADS)
Surender Reddy, S.; Abhyankar, A. R.; Bijwe, P. R.
2015-04-01
This paper presents a new multi-objective day-ahead market clearing (DAMC) mechanism with demand-side reserves/demand response (DR) offers, considering realistic voltage-dependent load modeling. The paper proposes objectives such as social welfare maximization (SWM) including demand-side reserves, and load served error (LSE) minimization. In this paper, energy and demand-side reserves are cleared simultaneously through co-optimization process. The paper clearly brings out the unsuitability of conventional SWM for DAMC in the presence of voltage-dependent loads, due to reduction of load served (LS). Under such circumstances multi-objective DAMC with DR offers is essential. Multi-objective Strength Pareto Evolutionary Algorithm 2+ (SPEA 2+) has been used to solve the optimization problem. The effectiveness of the proposed scheme is confirmed with results obtained from IEEE 30 bus system.
NASA Astrophysics Data System (ADS)
Sun, Xinyao; Wang, Xue; Wu, Jiangwei; Liu, Youda
2014-05-01
Cyber physical systems(CPS) recently emerge as a new technology which can provide promising approaches to demand side management(DSM), an important capability in industrial power systems. Meanwhile, the manufacturing center is a typical industrial power subsystem with dozens of high energy consumption devices which have complex physical dynamics. DSM, integrated with CPS, is an effective methodology for solving energy optimization problems in manufacturing center. This paper presents a prediction-based manufacturing center self-adaptive energy optimization method for demand side management in cyber physical systems. To gain prior knowledge of DSM operating results, a sparse Bayesian learning based componential forecasting method is introduced to predict 24-hour electric load levels for specific industrial areas in China. From this data, a pricing strategy is designed based on short-term load forecasting results. To minimize total energy costs while guaranteeing manufacturing center service quality, an adaptive demand side energy optimization algorithm is presented. The proposed scheme is tested in a machining center energy optimization experiment. An AMI sensing system is then used to measure the demand side energy consumption of the manufacturing center. Based on the data collected from the sensing system, the load prediction-based energy optimization scheme is implemented. By employing both the PSO and the CPSO method, the problem of DSM in the manufacturing center is solved. The results of the experiment show the self-adaptive CPSO energy optimization method enhances optimization by 5% compared with the traditional PSO optimization method.
CO2 Mitigation Measures of Power Sector and Its Integrated Optimization in China
Dai, Pan; Chen, Guang; Zhou, Hao; Su, Meirong; Bao, Haixia
2012-01-01
Power sector is responsible for about 40% of the total CO2 emissions in the world and plays a leading role in climate change mitigation. In this study, measures that lower CO2 emissions from the supply side, demand side, and power grid are discussed, based on which, an integrated optimization model of CO2 mitigation (IOCM) is proposed. Virtual energy, referring to energy saving capacity in both demand side and the power grid, together with conventional energy in supply side, is unified planning for IOCM. Consequently, the optimal plan of energy distribution, considering both economic benefits and mitigation benefits, is figured out through the application of IOCM. The results indicate that development of demand side management (DSM) and smart grid can make great contributions to CO2 mitigation of power sector in China by reducing the CO2 emissions by 10.02% and 12.59%, respectively, in 2015, and in 2020. PMID:23213305
NASA Astrophysics Data System (ADS)
Xue, Huaju; Fang, Chengjiang
2018-02-01
It is vital to assess the regional tourist supply capability by suppliers and demand groups. The supply side’s evaluation of the regional supply capacity determines the direction of the supply investment in future, the demand side’s evaluation indicates their satisfaction degree of the destination supply and also effects their revisit the tourism destination. Therefore, the assessment of the supply and demand sides is an important reference for the reform of destination supply side, which helps us find the shortage of the destination supply factors and optimize tourism destination supply promptly. This paper through investigating tourism supply and demand groups in Shanghai, used the survey data and constructed tourism supply optimization model, analyzed the current situation of tourism supply factors in Shanghai. Results showed that the environment of Shanghai should be improved first, including improving urban air and water quality, up-grading public sanitation and increasing urban green coverage. Other supply factors improved priority were information and marketing, we should improve the information consultation of scenic spots, increase the intensity of tourism promotion and provide more free travel publicity brochures.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Krishnan, Venkat; Ho, Jonathan; Hobbs, Benjamin F.
2016-05-01
The recognition of transmission's interaction with other resources has motivated the development of co-optimization methods to optimize transmission investment while simultaneously considering tradeoffs with investments in electricity supply, demand, and storage resources. For a given set of constraints, co-optimized planning models provide solutions that have lower costs than solutions obtained from decoupled optimization (transmission-only, generation-only, or iterations between them). This paper describes co-optimization and provides an overview of approaches to co-optimizing transmission options, supply-side resources, demand-side resources, and natural gas pipelines. In particular, the paper provides an up-to-date assessment of the present and potential capabilities of existing co-optimization tools, andmore » it discusses needs and challenges for developing advanced co-optimization models.« less
NASA Astrophysics Data System (ADS)
Sun, Congcong; Wang, Zhijie; Liu, Sanming; Jiang, Xiuchen; Sheng, Gehao; Liu, Tianyu
2017-05-01
Wind power has the advantages of being clean and non-polluting and the development of bundled wind-thermal generation power systems (BWTGSs) is one of the important means to improve wind power accommodation rate and implement “clean alternative” on generation side. A two-stage optimization strategy for BWTGSs considering wind speed forecasting results and load characteristics is proposed. By taking short-term wind speed forecasting results of generation side and load characteristics of demand side into account, a two-stage optimization model for BWTGSs is formulated. By using the environmental benefit index of BWTGSs as the objective function, supply-demand balance and generator operation as the constraints, the first-stage optimization model is developed with the chance-constrained programming theory. By using the operation cost for BWTGSs as the objective function, the second-stage optimization model is developed with the greedy algorithm. The improved PSO algorithm is employed to solve the model and numerical test verifies the effectiveness of the proposed strategy.
Electric power market agent design
NASA Astrophysics Data System (ADS)
Oh, Hyungseon
The electric power industry in many countries has been restructured in the hope of a more economically efficient system. In the restructured system, traditional operating and planning tools based on true marginal cost do not perform well since information required is strictly confidential. For developing a new tool, it is necessary to understand offer behavior. The main objective of this study is to create a new tool for power system planning. For the purpose, this dissertation develops models for a market and market participants. A new model is developed in this work for explaining a supply-side offer curve, and several variables are introduced to characterize the curve. Demand is estimated using a neural network, and a numerical optimization process is used to determine the values of the variables that maximize the profit of the agent. The amount of data required for the optimization is chosen with the aid of nonlinear dynamics. To suggest an optimal demand-side bidding function, two optimization problems are constructed and solved for maximizing consumer satisfaction based on the properties of two different types of demands: price-based demand and must-be-served demand. Several different simulations are performed to test how an agent reacts in various situations. The offer behavior depends on locational benefit as well as the offer strategies of competitors.
NASA Astrophysics Data System (ADS)
Huang, Y.; Liu, B. Z.; Wang, K. Y.; Ai, X.
2017-12-01
In response to the new requirements of the operation mode of wind-storage combined system and demand side response for transmission network planning, this paper presents a joint planning of energy storage and transmission considering wind-storage combined system and demand side response. Firstly, the charge-discharge strategy of energy storage system equipped at the outlet of wind farm and demand side response strategy are analysed to achieve the best comprehensive benefits through the coordination of the two. Secondly, in the general transmission network planning model with wind power, both energy storage cost and demand side response cost are added to the objective function. Not only energy storage operation constraints and but also demand side response constraints are introduced into the constraint condition. Based on the classical formulation of TEP, a new formulation is developed considering the simultaneous addition of the charge-discharge strategy of energy storage system equipped at the outlet of the wind farm and demand side response strategy, which belongs to a typical mixed integer linear programming model that can be solved by mature optimization software. The case study based on the Garver-6 bus system shows that the validity of the proposed model is verified by comparison with general transmission network planning model. Furthermore, the results demonstrate that the joint planning model can gain more economic benefits through setting up different cases.
Managing imperfect competition by pay for performance and reference pricing.
Mak, Henry Y
2018-01-01
I study a managed health service market where differentiated providers compete for consumers by choosing multiple service qualities, and where copayments that consumers pay and payments that providers receive for services are set by a payer. The optimal regulation scheme is two-sided. On the demand side, it justifies and clarifies value-based reference pricing. On the supply side, it prescribes pay for performance when consumers misperceive service benefits or providers have intrinsic quality incentives. The optimal bonuses are expressed in terms of demand elasticities, service technology, and provider characteristics. However, pay for performance may not outperform prospective payment when consumers are rational and providers are profit maximizing, or when one of the service qualities is not contractible. Copyright © 2017 Elsevier B.V. All rights reserved.
Optimal Drug Policy in Low-Income Neighborhoods
Chang, Sheng-Wen; Coulson, N. Edward; Wang, Ping
2015-01-01
The control of drug activity currently favors supply-side policies: drug suppliers in the U.S. face a higher arrest rate and longer sentences than demanders. We construct a simple model of drug activity with search and entry frictions in labor and drug markets. Our calibration analysis suggests a strong “dealer replacement effect.” As a result, given a variety of community objectives, it is beneficial to lower supplier arrests and raise the demand arrest rate from current values. A 10% shift from supply-side to demand-side arrests can reduce the population of potential drug dealers by 22–25,000 and raise aggregate local income by $380–400 million, at 2002 prices. (JEL Classification: D60, J60, K42, H70) PMID:27616878
Financing pharmaceuticals in transition economies.
Kanavos, P
1999-06-01
This paper (a) provides a methodological taxonomy of pricing, financing, reimbursement, and cost containment methodologies for pharmaceuticals; (b) analyzes complex agency relationships and the health versus industrial policy tradeoff; (c) pinpoints financing measures to balance safety and effectiveness of medicines and their affordability by publicly funded systems in transition; and (d) highlights viable options for policy-makers for the financing of pharmaceuticals in transition. Three categories of measures and their implications for pharmaceutical policy cost containing are analyzed: supply-side measures, targeting manufacturers, proxy demand-side measures, targeting physicians and pharmacists, and demand-side measures, targeting patients. In pursuing supply side measures, we explore free pricing for pharmaceuticals, direct price controls, cost-plus and cost pricing, average pricing and international price comparisons, profit control, reference pricing, the introduction of a fourth hurdle, positive and negative lists, and other price control measures. The analysis of proxy-demand measures includes budgets for physicians, generic policies, practice guidelines, monitoring the authorizing behavior of physicians, and disease management schemes. Demand-side measures explore the effectiveness of patient co-payments, the impact of allowing products over-the-counter and health promotion programs. Global policies should operate simultaneously on the supply, the proxy demand, and the demand-side. Policy-making needs to have a continuous long-term planning. The importation of policies into transition economy may require extensive and expensive adaptation, and/or lead to sub-optimal policy outcomes.
Optimal Load-Side Control for Frequency Regulation in Smart Grids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Changhong; Mallada, Enrique; Low, Steven
Frequency control rebalances supply and demand while maintaining the network state within operational margins. It is implemented using fast ramping reserves that are expensive and wasteful, and which are expected to become increasingly necessary with the current acceleration of renewable penetration. The most promising solution to this problem is the use of demand response, i.e., load participation in frequency control. Yet it is still unclear how to efficiently integrate load participation without introducing instabilities and violating operational constraints. In this paper, we present a comprehensive load-side frequency control mechanism that can maintain the grid within operational constraints. In particular, ourmore » controllers can rebalance supply and demand after disturbances, restore the frequency to its nominal value, and preserve interarea power flows. Furthermore, our controllers are distributed (unlike the currently implemented frequency control), can allocate load updates optimally, and can maintain line flows within thermal limits. We prove that such a distributed load-side control is globally asymptotically stable and robust to unknown load parameters. We illustrate its effectiveness through simulations.« less
Incentive-compatible demand-side management for smart grids based on review strategies
NASA Astrophysics Data System (ADS)
Xu, Jie; van der Schaar, Mihaela
2015-12-01
Demand-side load management is able to significantly improve the energy efficiency of smart grids. Since the electricity production cost depends on the aggregate energy usage of multiple consumers, an important incentive problem emerges: self-interested consumers want to increase their own utilities by consuming more than the socially optimal amount of energy during peak hours since the increased cost is shared among the entire set of consumers. To incentivize self-interested consumers to take the socially optimal scheduling actions, we design a new class of protocols based on review strategies. These strategies work as follows: first, a review stage takes place in which a statistical test is performed based on the daily prices of the previous billing cycle to determine whether or not the other consumers schedule their electricity loads in a socially optimal way. If the test fails, the consumers trigger a punishment phase in which, for a certain time, they adjust their energy scheduling in such a way that everybody in the consumer set is punished due to an increased price. Using a carefully designed protocol based on such review strategies, consumers then have incentives to take the socially optimal load scheduling to avoid entering this punishment phase. We rigorously characterize the impact of deploying protocols based on review strategies on the system's as well as the users' performance and determine the optimal design (optimal billing cycle, punishment length, etc.) for various smart grid deployment scenarios. Even though this paper considers a simplified smart grid model, our analysis provides important and useful insights for designing incentive-compatible demand-side management schemes based on aggregate energy usage information in a variety of practical scenarios.
NASA Astrophysics Data System (ADS)
Wahyuda; Santosa, Budi; Rusdiansyah, Ahmad
2018-04-01
Deregulation of the electricity market requires coordination between parties to synchronize the optimization on the production side (power station) and the transport side (transmission). Electricity supply chain presented in this article is designed to facilitate the coordination between the parties. Generally, the production side is optimized with price based dynamic economic dispatch (PBDED) model, while the transmission side is optimized with Multi-echelon distribution model. Both sides optimization are done separately. This article proposes a joint model of PBDED and multi-echelon distribution for the combined optimization of production and transmission. This combined optimization is important because changes in electricity demand on the customer side will cause changes to the production side that automatically also alter the transmission path. The transmission will cause two cost components. First, the cost of losses. Second, the cost of using the transmission network (wheeling transaction). Costs due to losses are calculated based on ohmic losses, while the cost of using transmission lines using the MW - mile method. As a result, this method is able to provide best allocation analysis for electrical transactions, as well as emission levels in power generation and cost analysis. As for the calculation of transmission costs, the Reverse MW-mile method produces a cheaper cost than the Absolute MW-mile method
Electrical load forecasting with artificial neural networks Demand-side management optimization with Matlab -58491. D. Palchak, S. Suryanarayanan, and D. Zimmerle. "An Artificial Neural Network in Short-Term
Optimal Operation of a Thermal Energy Storage Tank Using Linear Optimization
NASA Astrophysics Data System (ADS)
Civit Sabate, Carles
In this thesis, an optimization procedure for minimizing the operating costs of a Thermal Energy Storage (TES) tank is presented. The facility in which the optimization is based is the combined cooling, heating, and power (CCHP) plant at the University of California, Irvine. TES tanks provide the ability of decoupling the demand of chilled water from its generation, over the course of a day, from the refrigeration and air-conditioning plants. They can be used to perform demand-side management, and optimization techniques can help to approach their optimal use. The proposed optimization approach provides a fast and reliable methodology of finding the optimal use of the TES tank to reduce energy costs and provides a tool for future implementation of optimal control laws on the system. Advantages of the proposed methodology are studied using simulation with historical data.
Optimal Multi-scale Demand-side Management for Continuous Power-Intensive Processes
NASA Astrophysics Data System (ADS)
Mitra, Sumit
With the advent of deregulation in electricity markets and an increasing share of intermittent power generation sources, the profitability of industrial consumers that operate power-intensive processes has become directly linked to the variability in energy prices. Thus, for industrial consumers that are able to adjust to the fluctuations, time-sensitive electricity prices (as part of so-called Demand-Side Management (DSM) in the smart grid) offer potential economical incentives. In this thesis, we introduce optimization models and decomposition strategies for the multi-scale Demand-Side Management of continuous power-intensive processes. On an operational level, we derive a mode formulation for scheduling under time-sensitive electricity prices. The formulation is applied to air separation plants and cement plants to minimize the operating cost. We also describe how a mode formulation can be used for industrial combined heat and power plants that are co-located at integrated chemical sites to increase operating profit by adjusting their steam and electricity production according to their inherent flexibility. Furthermore, a robust optimization formulation is developed to address the uncertainty in electricity prices by accounting for correlations and multiple ranges in the realization of the random variables. On a strategic level, we introduce a multi-scale model that provides an understanding of the value of flexibility of the current plant configuration and the value of additional flexibility in terms of retrofits for Demand-Side Management under product demand uncertainty. The integration of multiple time scales leads to large-scale two-stage stochastic programming problems, for which we need to apply decomposition strategies in order to obtain a good solution within a reasonable amount of time. Hence, we describe two decomposition schemes that can be applied to solve two-stage stochastic programming problems: First, a hybrid bi-level decomposition scheme with novel Lagrangean-type and subset-type cuts to strengthen the relaxation. Second, an enhanced cross-decomposition scheme that integrates Benders decomposition and Lagrangean decomposition on a scenario basis. To demonstrate the effectiveness of our developed methodology, we provide several industrial case studies throughout the thesis.
NASA Astrophysics Data System (ADS)
Abdulaal, Ahmed
The work in this study addresses the current limitations of the price-driven demand response (DR) approach. Mainly, the dependability on consumers to respond in an energy aware conduct, the response timeliness, the difficulty of applying DR in a busy industrial environment, and the problem of load synchronization are of utmost concern. In order to conduct a simulation study, realistic price simulation model and consumers' building load models are created using real data. DR action is optimized using an autonomous control method, which eliminates the dependency on frequent consumer engagement. Since load scheduling and long-term planning approaches are infeasible in the industrial environment, the proposed method utilizes instantaneous DR in response to hour-ahead price signals (RTP-HA). Preliminary simulation results concluded savings at the consumer-side at the cost of increased supplier-side burden due to the aggregate effect of the universal DR policies. Therefore, a consumer disaggregation strategy is briefly discussed. Finally, a refined discrete-continuous control system is presented, which utilizes multi-objective Pareto optimization, evolutionary programming, utility functions, and bidirectional loads. Demonstrated through a virtual testbed fit with real data, the new system achieves momentary optimized DR in real-time while maximizing the consumer's wellbeing.
NASA Astrophysics Data System (ADS)
Tran, T.
With the onset of the SmallSat era, the RSO catalog is expected to see continuing growth in the near future. This presents a significant challenge to the current sensor tasking of the SSN. The Air Force is in need of a sensor tasking system that is robust, efficient, scalable, and able to respond in real-time to interruptive events that can change the tracking requirements of the RSOs. Furthermore, the system must be capable of using processed data from heterogeneous sensors to improve tasking efficiency. The SSN sensor tasking can be regarded as an economic problem of supply and demand: the amount of tracking data needed by each RSO represents the demand side while the SSN sensor tasking represents the supply side. As the number of RSOs to be tracked grows, demand exceeds supply. The decision-maker is faced with the problem of how to allocate resources in the most efficient manner. Braxton recently developed a framework called Multi-Objective Resource Optimization using Genetic Algorithm (MOROUGA) as one of its modern COTS software products. This optimization framework took advantage of the maturing technology of evolutionary computation in the last 15 years. This framework was applied successfully to address the resource allocation of an AFSCN-like problem. In any resource allocation problem, there are five key elements: (1) the resource pool, (2) the tasks using the resources, (3) a set of constraints on the tasks and the resources, (4) the objective functions to be optimized, and (5) the demand levied on the resources. In this paper we explain in detail how the design features of this optimization framework are directly applicable to address the SSN sensor tasking domain. We also discuss our validation effort as well as present the result of the AFSCN resource allocation domain using a prototype based on this optimization framework.
Scheduling Non-Preemptible Jobs to Minimize Peak Demand
Yaw, Sean; Mumey, Brendan
2017-10-28
Our paper examines an important problem in smart grid energy scheduling; peaks in power demand are proportionally more expensive to generate and provision for. The issue is exacerbated in local microgrids that do not benefit from the aggregate smoothing experienced by large grids. Demand-side scheduling can reduce these peaks by taking advantage of the fact that there is often flexibility in job start times. We then focus attention on the case where the jobs are non-preemptible, meaning once started, they run to completion. The associated optimization problem is called the peak demand minimization problem, and has been previously shown tomore » be NP-hard. These results include an optimal fixed-parameter tractable algorithm, a polynomial-time approximation algorithm, as well as an effective heuristic that can also be used in an online setting of the problem. Simulation results show that these methods can reduce peak demand by up to 50% versus on-demand scheduling for household power jobs.« less
Scheduling Non-Preemptible Jobs to Minimize Peak Demand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yaw, Sean; Mumey, Brendan
Our paper examines an important problem in smart grid energy scheduling; peaks in power demand are proportionally more expensive to generate and provision for. The issue is exacerbated in local microgrids that do not benefit from the aggregate smoothing experienced by large grids. Demand-side scheduling can reduce these peaks by taking advantage of the fact that there is often flexibility in job start times. We then focus attention on the case where the jobs are non-preemptible, meaning once started, they run to completion. The associated optimization problem is called the peak demand minimization problem, and has been previously shown tomore » be NP-hard. These results include an optimal fixed-parameter tractable algorithm, a polynomial-time approximation algorithm, as well as an effective heuristic that can also be used in an online setting of the problem. Simulation results show that these methods can reduce peak demand by up to 50% versus on-demand scheduling for household power jobs.« less
On the Water-Food Nexus: an Optimization Approach for Water and Food Security
NASA Astrophysics Data System (ADS)
Mortada, Sarah; Abou Najm, Majdi; Yassine, Ali; Alameddine, Ibrahim; El-Fadel, Mutasem
2016-04-01
Water and food security is facing increased challenges with population increase, climate and land use change, as well as resource depletion coupled with pollution and unsustainable practices. Coordinated and effective management of limited natural resources have become an imperative to meet these challenges by optimizing the usage of resources under various constraints. In this study, an optimization model is developed for optimal resource allocation towards sustainable water and food security under nutritional, socio-economic, agricultural, environmental, and natural resources constraints. The core objective of this model is to maximize the composite water-food security status by recommending an optimal water and agricultural strategy. The model balances between the healthy nutritional demand side and the constrained supply side while considering the supply chain in between. It equally ensures that the population achieves recommended nutritional guidelines and population food-preferences by quantifying an optimum agricultural and water policy through transforming optimum food demands into optimum cropping policy given the water and land footprints of each crop or agricultural product. Through this process, water and food security are optimized considering factors that include crop-food transformation (food processing), water footprints, crop yields, climate, blue and green water resources, irrigation efficiency, arable land resources, soil texture, and economic policies. The model performance regarding agricultural practices and sustainable food and water security was successfully tested and verified both at a hypothetical and pilot scale levels.
Real-Time Load-Side Control of Electric Power Systems
NASA Astrophysics Data System (ADS)
Zhao, Changhong
Two trends are emerging from modern electric power systems: the growth of renewable (e.g., solar and wind) generation, and the integration of information technologies and advanced power electronics. The former introduces large, rapid, and random fluctuations in power supply, demand, frequency, and voltage, which become a major challenge for real-time operation of power systems. The latter creates a tremendous number of controllable intelligent endpoints such as smart buildings and appliances, electric vehicles, energy storage devices, and power electronic devices that can sense, compute, communicate, and actuate. Most of these endpoints are distributed on the load side of power systems, in contrast to traditional control resources such as centralized bulk generators. This thesis focuses on controlling power systems in real time, using these load side resources. Specifically, it studies two problems. (1) Distributed load-side frequency control: We establish a mathematical framework to design distributed frequency control algorithms for flexible electric loads. In this framework, we formulate a category of optimization problems, called optimal load control (OLC), to incorporate the goals of frequency control, such as balancing power supply and demand, restoring frequency to its nominal value, restoring inter-area power flows, etc., in a way that minimizes total disutility for the loads to participate in frequency control by deviating from their nominal power usage. By exploiting distributed algorithms to solve OLC and analyzing convergence of these algorithms, we design distributed load-side controllers and prove stability of closed-loop power systems governed by these controllers. This general framework is adapted and applied to different types of power systems described by different models, or to achieve different levels of control goals under different operation scenarios. We first consider a dynamically coherent power system which can be equivalently modeled with a single synchronous machine. We then extend our framework to a multi-machine power network, where we consider primary and secondary frequency controls, linear and nonlinear power flow models, and the interactions between generator dynamics and load control. (2) Two-timescale voltage control: The voltage of a power distribution system must be maintained closely around its nominal value in real time, even in the presence of highly volatile power supply or demand. For this purpose, we jointly control two types of reactive power sources: a capacitor operating at a slow timescale, and a power electronic device, such as a smart inverter or a D-STATCOM, operating at a fast timescale. Their control actions are solved from optimal power flow problems at two timescales. Specifically, the slow-timescale problem is a chance-constrained optimization, which minimizes power loss and regulates the voltage at the current time instant while limiting the probability of future voltage violations due to stochastic changes in power supply or demand. This control framework forms the basis of an optimal sizing problem, which determines the installation capacities of the control devices by minimizing the sum of power loss and capital cost. We develop computationally efficient heuristics to solve the optimal sizing problem and implement real-time control. Numerical experiments show that the proposed sizing and control schemes significantly improve the reliability of voltage control with a moderate increase in cost.
Robust Unit Commitment Considering Uncertain Demand Response
Liu, Guodong; Tomsovic, Kevin
2014-09-28
Although price responsive demand response has been widely accepted as playing an important role in the reliable and economic operation of power system, the real response from demand side can be highly uncertain due to limited understanding of consumers' response to pricing signals. To model the behavior of consumers, the price elasticity of demand has been explored and utilized in both research and real practice. However, the price elasticity of demand is not precisely known and may vary greatly with operating conditions and types of customers. To accommodate the uncertainty of demand response, alternative unit commitment methods robust to themore » uncertainty of the demand response require investigation. In this paper, a robust unit commitment model to minimize the generalized social cost is proposed for the optimal unit commitment decision taking into account uncertainty of the price elasticity of demand. By optimizing the worst case under proper robust level, the unit commitment solution of the proposed model is robust against all possible realizations of the modeled uncertain demand response. Numerical simulations on the IEEE Reliability Test System show the e ectiveness of the method. Finally, compared to unit commitment with deterministic price elasticity of demand, the proposed robust model can reduce the average Locational Marginal Prices (LMPs) as well as the price volatility.« less
A Vision for Co-optimized T&D System Interaction with Renewables and Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Lindsay; Zéphyr, Luckny; Cardell, Judith B.
The evolution of the power system to the reliable, efficient and sustainable system of the future will involve development of both demand- and supply-side technology and operations. The use of demand response to counterbalance the intermittency of renewable generation brings the consumer into the spotlight. Though individual consumers are interconnected at the low-voltage distribution system, these resources are typically modeled as variables at the transmission network level. In this paper, a vision for cooptimized interaction of distribution systems, or microgrids, with the high-voltage transmission system is described. In this framework, microgrids encompass consumers, distributed renewables and storage. The energy managementmore » system of the microgrid can also sell (buy) excess (necessary) energy from the transmission system. Preliminary work explores price mechanisms to manage the microgrid and its interactions with the transmission system. Wholesale market operations are addressed through the development of scalable stochastic optimization methods that provide the ability to co-optimize interactions between the transmission and distribution systems. Modeling challenges of the co-optimization are addressed via solution methods for large-scale stochastic optimization, including decomposition and stochastic dual dynamic programming.« less
A Vision for Co-optimized T&D System Interaction with Renewables and Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, C. Lindsay; Zéphyr, Luckny; Liu, Jialin
The evolution of the power system to the reliable, effi- cient and sustainable system of the future will involve development of both demand- and supply-side technology and operations. The use of demand response to counterbalance the intermittency of re- newable generation brings the consumer into the spotlight. Though individual consumers are interconnected at the low-voltage distri- bution system, these resources are typically modeled as variables at the transmission network level. In this paper, a vision for co- optimized interaction of distribution systems, or microgrids, with the high-voltage transmission system is described. In this frame- work, microgrids encompass consumers, distributed renewablesmore » and storage. The energy management system of the microgrid can also sell (buy) excess (necessary) energy from the transmission system. Preliminary work explores price mechanisms to manage the microgrid and its interactions with the transmission system. Wholesale market operations are addressed through the devel- opment of scalable stochastic optimization methods that provide the ability to co-optimize interactions between the transmission and distribution systems. Modeling challenges of the co-optimization are addressed via solution methods for large-scale stochastic op- timization, including decomposition and stochastic dual dynamic programming.« less
Modeling and Analysis of Commercial Building Electrical Loads for Demand Side Management
NASA Astrophysics Data System (ADS)
Berardino, Jonathan
In recent years there has been a push in the electric power industry for more customer involvement in the electricity markets. Traditionally the end user has played a passive role in the planning and operation of the power grid. However, many energy markets have begun opening up opportunities to consumers who wish to commit a certain amount of their electrical load under various demand side management programs. The potential benefits of more demand participation include reduced operating costs and new revenue opportunities for the consumer, as well as more reliable and secure operations for the utilities. The management of these load resources creates challenges and opportunities to the end user that were not present in previous market structures. This work examines the behavior of commercial-type building electrical loads and their capacity for supporting demand side management actions. This work is motivated by the need for accurate and dynamic tools to aid in the advancement of demand side operations. A dynamic load model is proposed for capturing the response of controllable building loads. Building-specific load forecasting techniques are developed, with particular focus paid to the integration of building management system (BMS) information. These approaches are tested using Drexel University building data. The application of building-specific load forecasts and dynamic load modeling to the optimal scheduling of multi-building systems in the energy market is proposed. Sources of potential load uncertainty are introduced in the proposed energy management problem formulation in order to investigate the impact on the resulting load schedule.
High Penetration of Electrical Vehicles in Microgrids: Threats and Opportunities
NASA Astrophysics Data System (ADS)
Khederzadeh, Mojtaba; Khalili, Mohammad
2014-10-01
Given that the microgrid concept is the building block of future electric distribution systems and electrical vehicles (EVs) are the future of transportation market, in this paper, the impact of EVs on the performance of microgrids is investigated. Demand-side participation is used to cope with increasing demand for EV charging. The problem of coordination of EV charging and discharging (with vehicle-to-grid (V2G) functionality) and demand response is formulated as a market-clearing mechanism that accepts bids from the demand and supply sides and takes into account the constraints put forward by different parts. Therefore, a day-ahead market with detailed bids and offers within the microgrid is designed whose objective is to maximize the social welfare which is the difference between the value that consumers attach to the electrical energy they buy plus the benefit of the EV owners participating in the V2G functionality and the cost of producing/purchasing this energy. As the optimization problem is a mixed integer nonlinear programming one, it is decomposed into one master problem for energy scheduling and one subproblem for power flow computation. The two problems are solved iteratively by interfacing MATLAB with GAMS. Simulation results on a sample microgrid with different residential, commercial and industrial consumers with associated demand-side biddings and different penetration level of EVs support the proposed formulation of the problem and the applied methods.
Ye, Quanliang; Li, Yi; Zhuo, La; Zhang, Wenlong; Xiong, Wei; Wang, Chao; Wang, Peifang
2018-02-01
This study provides an innovative application of virtual water trade in the traditional allocation of physical water resources in water scarce regions. A multi-objective optimization model was developed to optimize the allocation of physical water and virtual water resources to different water users in Beijing, China, considering the trade-offs between economic benefit and environmental impacts of water consumption. Surface water, groundwater, transferred water and reclaimed water constituted the physical resource of water supply side, while virtual water flow associated with the trade of five major crops (barley, corn, rice, soy and wheat) and three livestock products (beef, pork and poultry) in agricultural sector (calculated by the trade quantities of products and their virtual water contents). Urban (daily activities and public facilities), industry, environment and agriculture (products growing) were considered in water demand side. As for the traditional allocation of physical water resources, the results showed that agriculture and urban were the two predominant water users (accounting 54% and 28%, respectively), while groundwater and surface water satisfied around 70% water demands of different users (accounting 36% and 34%, respectively). When considered the virtual water trade of eight agricultural products in water allocation procedure, the proportion of agricultural consumption decreased to 45% in total water demand, while the groundwater consumption decreased to 24% in total water supply. Virtual water trade overturned the traditional components of water supplied from different sources for agricultural consumption, and became the largest water source in Beijing. Additionally, it was also found that environmental demand took a similar percentage of water consumption in each water source. Reclaimed water was the main water source for industrial and environmental users. The results suggest that physical water resources would mainly satisfy the consumption of urban and environment, and the unbalance between water supply and demand could be filled by virtual water import in water scarce regions. Copyright © 2017 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghatikar, Girish; Mashayekh, Salman; Stadler, Michael
Distributed power systems in the U.S. and globally are evolving to provide reliable and clean energy to consumers. In California, existing regulations require significant increases in renewable generation, as well as identification of customer-side distributed energy resources (DER) controls, communication technologies, and standards for interconnection with the electric grid systems. As DER deployment expands, customer-side DER control and optimization will be critical for system flexibility and demand response (DR) participation, which improves the economic viability of DER systems. Current DER systems integration and communication challenges include leveraging the existing DER and DR technology and systems infrastructure, and enabling optimized cost,more » energy and carbon choices for customers to deploy interoperable grid transactions and renewable energy systems at scale. Our paper presents a cost-effective solution to these challenges by exploring communication technologies and information models for DER system integration and interoperability. This system uses open standards and optimization models for resource planning based on dynamic-pricing notifications and autonomous operations within various domains of the smart grid energy system. It identifies architectures and customer engagement strategies in dynamic DR pricing transactions to generate feedback information models for load flexibility, load profiles, and participation schedules. The models are tested at a real site in California—Fort Hunter Liggett (FHL). Furthermore, our results for FHL show that the model fits within the existing and new DR business models and networked systems for transactive energy concepts. Integrated energy systems, communication networks, and modeling tools that coordinate supply-side networks and DER will enable electric grid system operators to use DER for grid transactions in an integrated system.« less
Meeting China's electricity needs through clean energy sources: A 2030 low-carbon energy roadmap
NASA Astrophysics Data System (ADS)
Hu, Zheng
China is undergoing rapid economic development that generates significant increase in energy demand, primarily for electricity. Energy supply in China is heavily relying on coal, which leads to high carbon emissions. This dissertation explores opportunities for meeting China's growing power demand through clean energy sources. The utilization of China's clean energy sources as well as demand-side management is still at the initial phase. Therefore, development of clean energy sources would require substantial government support in order to be competitive in the market. One of the widely used means to consider clean energy in power sector supplying is Integrated Resource Strategic Planning, which aims to minimize the long term electricity costs while screening various power supply options for the power supply and demand analysis. The IRSP tool tackles the energy problem from the perspective of power sector regulators, and provides different policy scenarios to quantify the impacts of combined incentives. Through three scenario studies, Business as Usual, High Renewable, and Renewable and Demand Side Management, this dissertation identifies the optimized scenario for China to achieve the clean energy target of 2030. The scenarios are assessed through energy, economics, environment, and equity dimensions.
Discrete Optimization Model for Vehicle Routing Problem with Scheduling Side Cosntraints
NASA Astrophysics Data System (ADS)
Juliandri, Dedy; Mawengkang, Herman; Bu'ulolo, F.
2018-01-01
Vehicle Routing Problem (VRP) is an important element of many logistic systems which involve routing and scheduling of vehicles from a depot to a set of customers node. This is a hard combinatorial optimization problem with the objective to find an optimal set of routes used by a fleet of vehicles to serve the demands a set of customers It is required that these vehicles return to the depot after serving customers’ demand. The problem incorporates time windows, fleet and driver scheduling, pick-up and delivery in the planning horizon. The goal is to determine the scheduling of fleet and driver and routing policies of the vehicles. The objective is to minimize the overall costs of all routes over the planning horizon. We model the problem as a linear mixed integer program. We develop a combination of heuristics and exact method for solving the model.
Automated Dynamic Demand Response Implementation on a Micro-grid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuppannagari, Sanmukh R.; Kannan, Rajgopal; Chelmis, Charalampos
In this paper, we describe a system for real-time automated Dynamic and Sustainable Demand Response with sparse data consumption prediction implemented on the University of Southern California campus microgrid. Supply side approaches to resolving energy supply-load imbalance do not work at high levels of renewable energy penetration. Dynamic Demand Response (D 2R) is a widely used demand-side technique to dynamically adjust electricity consumption during peak load periods. Our D 2R system consists of accurate machine learning based energy consumption forecasting models that work with sparse data coupled with fast and sustainable load curtailment optimization algorithms that provide the ability tomore » dynamically adapt to changing supply-load imbalances in near real-time. Our Sustainable DR (SDR) algorithms attempt to distribute customer curtailment evenly across sub-intervals during a DR event and avoid expensive demand peaks during a few sub-intervals. It also ensures that each customer is penalized fairly in order to achieve the targeted curtailment. We develop near linear-time constant-factor approximation algorithms along with Polynomial Time Approximation Schemes (PTAS) for SDR curtailment that minimizes the curtailment error defined as the difference between the target and achieved curtailment values. Our SDR curtailment problem is formulated as an Integer Linear Program that optimally matches customers to curtailment strategies during a DR event while also explicitly accounting for customer strategy switching overhead as a constraint. We demonstrate the results of our D 2R system using real data from experiments performed on the USC smartgrid and show that 1) our prediction algorithms can very accurately predict energy consumption even with noisy or missing data and 2) our curtailment algorithms deliver DR with extremely low curtailment errors in the 0.01-0.05 kWh range.« less
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.
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.
Procuring load curtailment from local customers under uncertainty.
Mijatović, Aleksandar; Moriarty, John; Vogrinc, Jure
2017-08-13
Demand side response (DSR) provides a flexible approach to managing constrained power network assets. This is valuable if future asset utilization is uncertain. However there may be uncertainty over the process of procurement of DSR from customers. In this context we combine probabilistic modelling, simulation and optimization to identify economically optimal procurement policies from heterogeneous customers local to the asset, under chance constraints on the adequacy of the procured DSR. Mathematically this gives rise to a search over permutations, and we provide an illustrative example implementation and case study.This article is part of the themed issue 'Energy management: flexibility, risk and optimization'. © 2017 The Author(s).
NASA Astrophysics Data System (ADS)
Schmidt, R. D.; Taylor, R. G.; Stodick, L. D.; Contor, B. A.
2009-12-01
A recent federal interagency report on climate change and water management (Brekke et. al., 2009) describes several possible management responses to the impacts of climate change on water supply and demand. Management alternatives include changes to water supply infrastructure, reservoir system operations, and water demand policies. Water users in the Bureau of Reclamation’s Boise Project (located in the Lower Boise River basin in southwestern Idaho) would be among those impacted both hydrologically and economically by climate change. Climate change and management responses to climate change are expected to cause shifts in water supply and demand. Supply shifts would result from changes in basin precipitation patterns, and demand shifts would result from higher evapotranspiration rates and a longer growing season. The impacts would also extend to non-Project water users in the basin, since most non-Project groundwater pumpers and drain water diverters rely on hydrologic externalities created by seepage losses from Boise Project water deliveries. An integrated hydrologic-economic model was developed for the Boise basin to aid Reclamation in evaluating the hydrologic and economic impacts of various management responses to climate change. A spatial, partial-equilibrium, economic optimization model calculates spatially-distinct equilibrium water prices and quantities, and maximizes a social welfare function (the sum of consumer and producers surpluses) for all agricultural and municipal water suppliers and demanders (both Project and non-Project) in the basin. Supply-price functions and demand-price functions are exogenous inputs to the economic optimization model. On the supply side, groundwater and river/reservoir models are used to generate hydrologic responses to various management alternatives. The response data is then used to develop water supply-price functions for Project and non-Project water users. On the demand side, crop production functions incorporating crop distribution, evapotranspiration rates, irrigation efficiencies, and crop prices are used to develop water demand-price functions for agricultural water users. Demand functions for municipal and industrial water users are also developed. Recent applications of the integrated model have focused on the hydrologic and economic impacts of demand management alternatives, including large-scale canal lining conservation measures, and market-based water trading between canal diverters and groundwater pumpers. A supply management alternative being investigated involves revising reservoir rule curves to compensate for climate change impacts on timing of reservoir filling.
Towards demand-side solutions for mitigating climate change
NASA Astrophysics Data System (ADS)
Creutzig, Felix; Roy, Joyashree; Lamb, William F.; Azevedo, Inês M. L.; Bruine de Bruin, Wändi; Dalkmann, Holger; Edelenbosch, Oreane Y.; Geels, Frank W.; Grubler, Arnulf; Hepburn, Cameron; Hertwich, Edgar G.; Khosla, Radhika; Mattauch, Linus; Minx, Jan C.; Ramakrishnan, Anjali; Rao, Narasimha D.; Steinberger, Julia K.; Tavoni, Massimo; Ürge-Vorsatz, Diana; Weber, Elke U.
2018-04-01
Research on climate change mitigation tends to focus on supply-side technology solutions. A better understanding of demand-side solutions is missing. We propose a transdisciplinary approach to identify demand-side climate solutions, investigate their mitigation potential, detail policy measures and assess their implications for well-being.
Castellano, Julen; Casamichana, David; Dellal, Alexandre
2013-05-01
The aim of the study was to examine the extent to which changing the game format (possession play vs. regulation goals and goalkeepers vs. small goals only) and the number of players (3 vs. 3, 5 vs. 5 and 7 vs. 7) influenced the physiological and physical demands of small-sided games (SSGs) in soccer in semiprofessional players. Fourteen semiprofessional male soccer players were monitored with global positioning system and heart rate devices. Heart rate, player load, distance covered, running speed, and the number of accelerations were recorded for 9 different SSGs. The results show that changes both in game format and the number of players affect the players' physiological and physical demands. Possession play places greater physiological and physical demands on players, although reducing the number of players only increases the physiological load. In the 7 vs. 7 games, changing the game format did not alter the heart rate responses. Finally, in the possession play format, changing the number of players did not produce significant differences in heart rate responses, although physical demands did decrease in line with a reduction in the number of players. These results should help coaches to understand how modifying different aspects of SSGs has a differential effect on the players' physiological and physical demands. Moreover, coaches in semiprofessional and amateur teams have now consistent information to design and optimize their training time in mixing the technical, tactical, and physical aspects.
Carbon and energy footprint of electrochemical vinegar wastewater treatment
NASA Astrophysics Data System (ADS)
Gerek, Emine Esra; Yilmaz, Seval; Savaş Koparal, A.; Nezih Gerek, Ömer
2017-11-01
Electrochemical treatment of wastewaters that are rich in organic compounds is a popular method, due to its acidic nature that avoids biological treatment. In many cases, the pollution hazard is considered as the chemical oxygen demand (COD) from active carbon, and the success of the treatment is measured in terms of how much this specific parameter is reduced. However, if electricity is used during the treatment process, the treatment "itself" has manufacturing and operational energy costs. Many of the studies consider energy utilization as a monetary cost, and try to reduce its amount. However, the energy cost of the treatment also causes emission of carbon at the energy producing side of the closed loop. This carbon emission can be converted into oxygen demand, too. Therefore, it can be argued that one must look for the total optimal carbon efficiency (or oxygen demand), while reducing the COD. We chose a highly acidic wastewater case of vinegar production, which is a popular food product in Turkey, to demonstrate the high energy consumption and carbon emission problem of the electrochemical treatment approach. A novel strategy is presented to monitor total oxygen demand simultaneously at the treatment and energy production sides. Necessity of renewable energy utilization and conditions on process termination points are discussed.
Robust optimization of front members in a full frontal car impact
NASA Astrophysics Data System (ADS)
Aspenberg (né Lönn), David; Jergeus, Johan; Nilsson, Larsgunnar
2013-03-01
In the search for lightweight automobile designs, it is necessary to assure that robust crashworthiness performance is achieved. Structures that are optimized to handle a finite number of load cases may perform poorly when subjected to various dispersions. Thus, uncertainties must be accounted for in the optimization process. This article presents an approach to optimization where all design evaluations include an evaluation of the robustness. Metamodel approximations are applied both to the design space and the robustness evaluations, using artifical neural networks and polynomials, respectively. The features of the robust optimization approach are displayed in an analytical example, and further demonstrated in a large-scale design example of front side members of a car. Different optimization formulations are applied and it is shown that the proposed approach works well. It is also concluded that a robust optimization puts higher demands on the finite element model performance than normally.
Transmission congestion management in the electricity market
NASA Astrophysics Data System (ADS)
Chen, Yue
2018-04-01
In this paper we mainly discuss how to optimize the arrangement to decrease the loss of each line when the power generation side of the system transmission congestion occurs in a safe and economical manner. We respectively set the adjust model if the transmission can be eliminated which can calculate the best scheme and safety margin model when transmission cannot be eliminated which is a multi-objective planning problem. We solve the two models on the condition of the load power demands are 982.4MW and 1052.8 MW by Lingo and get the optimal management scheme.
NASA Astrophysics Data System (ADS)
Kamal, Rajeev
Buildings contribute a significant part to the electricity demand profile and peak demand for the electrical utilities. The addition of renewable energy generation adds additional variability and uncertainty to the power system. Demand side management in the buildings can help improve the demand profile for the utilities by shifting some of the demand from peak to off-peak times. Heating, ventilation and air-conditioning contribute around 45% to the overall demand of a building. This research studies two strategies for reducing the peak as well as shifting some demand from peak to off-peak periods in commercial buildings: 1. Use of gas heat pumps in place of electric heat pumps, and 2. Shifting demand for air conditioning from peak to off-peak by thermal energy storage in chilled water and ice. The first part of this study evaluates the field performance of gas engine-driven heat pumps (GEHP) tested in a commercial building in Florida. Four GEHP units of 8 Tons of Refrigeration (TR) capacity each providing air-conditioning to seven thermal zones in a commercial building, were instrumented for measuring their performance. The operation of these GEHPs was recorded for ten months, analyzed and compared with prior results reported in the literature. The instantaneous COPunit of these systems varied from 0.1 to 1.4 during typical summer week operation. The COP was low because the gas engines for the heat pumps were being used for loads that were much lower than design capacity which resulted in much lower efficiencies than expected. The performance of equivalent electric heat pump was simulated from a building energy model developed to mimic the measured building loads. An economic comparison of GEHPs and conventional electrical heat pumps was done based on the measured and simulated results. The average performance of the GEHP units was estimated to lie between those of EER-9.2 and EER-11.8 systems. The performance of GEHP systems suffers due to lower efficiency at part load operation. The study highlighted the need for optimum system sizing for GEHP/HVAC systems to meet the building load to obtain better performance in buildings. The second part of this study focusses on using chilled water or ice as thermal energy storage for shifting the air conditioning load from peak to off-peak in a commercial building. Thermal energy storage can play a very important role in providing demand-side management for diversifying the utility demand from buildings. Model of a large commercial office building is developed with thermal storage for cooling for peak power shifting. Three variations of the model were developed and analyzed for their performance with 1) ice storage, 2) chilled water storage with mixed storage tank and 3) chilled water storage with stratified tank, using EnergyPlus 8.5 software developed by the US Department of Energy. Operation strategy with tactical control to incorporate peak power schedule was developed using energy management system (EMS). The modeled HVAC system was optimized for minimum cost with the optimal storage capacity and chiller size using JEPlus. Based on the simulation, an optimal storage capacity of 40-45 GJ was estimated for the large office building model along with 40% smaller chiller capacity resulting in higher chiller part-load performance. Additionally, the auxiliary system like pump and condenser were also optimized to smaller capacities and thus resulting in less power demand during operation. The overall annual saving potential was found in the range of 7-10% for cooling electricity use resulting in 10-17% reduction in costs to the consumer. A possible annual peak shifting of 25-78% was found from the simulation results after comparing with the reference models. Adopting TES in commercial buildings and achieving 25% peak shifting could result in a reduction in peak summer demand of 1398 MW in Tampa.
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.
Research on service strategy of electricity selling company under the reform of electricity market
NASA Astrophysics Data System (ADS)
Long, Zhuhan; Meng, Shiyu; Dou, Jinyue; Zeng, Ming; Sun, Chenjun
2017-10-01
The opening of the sale side of electricity market is an important goal of the new round of power system reform in China, and it is necessary to speed up the establishment and development of the electricity selling companies to achieve this goal. First of all, this paper defines the key problems, which are needed to be solved in the establishment of the sale side market, such as demand side response, optimization of users' power consumption mode, profit mode of electricity selling companies and fair competition in the market. On this basis, this paper analyzes the business of electricity selling company, from the aspects of the transition of business ideas, improving the energy efficiency level, providing integrated energy solutions and innovating business management mode; and then, the service strategies of electricity selling companies are put forward.
NASA Astrophysics Data System (ADS)
Kanta, L.; Berglund, E. Z.
2015-12-01
Urban water supply systems may be managed through supply-side and demand-side strategies, which focus on water source expansion and demand reductions, respectively. Supply-side strategies bear infrastructure and energy costs, while demand-side strategies bear costs of implementation and inconvenience to consumers. To evaluate the performance of demand-side strategies, the participation and water use adaptations of consumers should be simulated. In this study, a Complex Adaptive Systems (CAS) framework is developed to simulate consumer agents that change their consumption to affect the withdrawal from the water supply system, which, in turn influences operational policies and long-term resource planning. Agent-based models are encoded to represent consumers and a policy maker agent and are coupled with water resources system simulation models. The CAS framework is coupled with an evolutionary computation-based multi-objective methodology to explore tradeoffs in cost, inconvenience to consumers, and environmental impacts for both supply-side and demand-side strategies. Decisions are identified to specify storage levels in a reservoir that trigger (1) increases in the volume of water pumped through inter-basin transfers from an external reservoir and (2) drought stages, which restrict the volume of water that is allowed for residential outdoor uses. The proposed methodology is demonstrated for Arlington, Texas, water supply system to identify non-dominated strategies for an historic drought decade. Results demonstrate that pumping costs associated with maximizing environmental reliability exceed pumping costs associated with minimizing restrictions on consumer water use.
America's Opioid Epidemic: Supply and Demand Considerations.
Clark, David J; Schumacher, Mark A
2017-11-01
America is in the midst of an opioid epidemic characterized by aggressive prescribing practices, highly prevalent opioid misuse, and rising rates of prescription and illicit opioid overdose-related deaths. Medical and lay public sentiment have become more cautious with respect to prescription opioid use in the past few years, but a comprehensive strategy to reduce our reliance on prescription opioids is lacking. Addressing this epidemic through reductions in unnecessary access to these drugs while implementing measures to reduce demand will be important components of any comprehensive solution. Key supply-side measures include avoiding overprescribing, reducing diversion, and discouraging misuse through changes in drug formulations. Important demand-side measures center around educating patients and clinicians regarding the pitfalls of opioid overuse and methods to avoid unnecessary exposure to these drugs. Anesthesiologists, by virtue of their expertise in the use of these drugs and their position in guiding opioid use around the time of surgery, have important roles to play in reducing patient exposure to opioids and providing education about appropriate use. Aside from the many immediate steps that can be taken, clinical and basic research directed at understanding the interaction between pain and opioid misuse is critical to identifying the optimal use of these powerful pain relievers in clinical practice.
Mathematical Model and Artificial Intelligent Techniques Applied to a Milk Industry through DSM
NASA Astrophysics Data System (ADS)
Babu, P. Ravi; Divya, V. P. Sree
2011-08-01
The resources for electrical energy are depleting and hence the gap between the supply and the demand is continuously increasing. Under such circumstances, the option left is optimal utilization of available energy resources. The main objective of this chapter is to discuss about the Peak load management and overcome the problems associated with it in processing industries such as Milk industry with the help of DSM techniques. The chapter presents a generalized mathematical model for minimizing the total operating cost of the industry subject to the constraints. The work presented in this chapter also deals with the results of application of Neural Network, Fuzzy Logic and Demand Side Management (DSM) techniques applied to a medium scale milk industrial consumer in India to achieve the improvement in load factor, reduction in Maximum Demand (MD) and also the consumer gets saving in the energy bill.
A Decision-making Model for a Two-stage Production-delivery System in SCM Environment
NASA Astrophysics Data System (ADS)
Feng, Ding-Zhong; Yamashiro, Mitsuo
A decision-making model is developed for an optimal production policy in a two-stage production-delivery system that incorporates a fixed quantity supply of finished goods to a buyer at a fixed interval of time. First, a general cost model is formulated considering both supplier (of raw materials) and buyer (of finished products) sides. Then an optimal solution to the problem is derived on basis of the cost model. Using the proposed model and its optimal solution, one can determine optimal production lot size for each stage, optimal number of transportation for semi-finished goods, and optimal quantity of semi-finished goods transported each time to meet the lumpy demand of consumers. Also, we examine the sensitivity of raw materials ordering and production lot size to changes in ordering cost, transportation cost and manufacturing setup cost. A pragmatic computation approach for operational situations is proposed to solve integer approximation solution. Finally, we give some numerical examples.
Development and Comparison of Technical Solutions for Electricity Monitoring Equipment
NASA Astrophysics Data System (ADS)
Potapovs, A.; Obushevs, A.
2017-12-01
The paper focuses on the elaboration of a demand-side management platform for optimal energy management strategies; the topicality is related to the description and comparison of the developed electricity monitoring and control equipment. The article describes two versions based on Atmega328 and STM32 microcontrollers, a lower and higher level of precision, and other distinct performance parameters. At the end of the article, the results of the testing of the two types of equipment are given and their comparison is made.
Managing Sustainable Demand-side Infrastructure for Power System Ancillary Services
NASA Astrophysics Data System (ADS)
Parkinson, Simon Christopher
Widespread access to renewable electricity is seen as a viable method to mitigate carbon emissions, although problematic are the issues associated with the integration of the generation systems within current power system configurations. Wind power plants are the primary large-scale renewable generation technology applied globally, but display considerable short-term supply variability that is difficult to predict. Power systems are currently not designed to operate under these conditions, and results in the need to increase operating reserve in order to guarantee stability. Often, operating conventional generation as reserve is both technically and economically inefficient, which can overshadow positive benefits associated with renewable energy exploitation. The purpose of this thesis is to introduce and assess an alternative method of enhancing power system operations through the control of electric loads. In particular, this thesis focuses on managing highly-distributed sustainable demand-side infrastructure, in the form of heat pumps, electric vehicles, and electrolyzers, as dispatchable short-term energy balancing resources. The main contribution of the thesis is an optimal control strategy capable of simultaneously balancing grid- and demand-side objectives. The viability of the load control strategy is assessed through model-based simulations that explicitly track end-use functionality of responsive devices within a power systems analysis typically implemented to observe the effects of integrated wind energy systems. Results indicate that there is great potential for the proposed method to displace the need for increased reserve capacity in systems considering a high penetration of wind energy, thereby allowing conventional generation to operate more efficiently and avoid the need for possible capacity expansions.
Physiological and skill demands of 'on-side' and 'off-side' games.
Gabbett, Tim J; Jenkins, David G; Abernethy, Bruce
2010-11-01
This study investigated the physiological and skill demands of 'on-side' and 'off-side' games in elite rugby league players. Sixteen male rugby league players participated in 'on-side' and 'off-side' games. Both small-sided games were played in a 40- × 40-m playing area. The 'off-side' game permitted players to have 3 'plays' while in possession of the ball. Players were permitted to pass backward or forward (to an 'off-side' player). The 'on-side' game also permitted players to have 3 'plays' while in possession of the ball. However, players were only permitted to pass backward to players in an 'on-side' position. Heart rate and movement patterns (via global positioning system) were recorded continuously throughout both games. Data were collected on the distance covered, number of high-acceleration and velocity efforts, and recovery between efforts. Video footage was also taken to track the performance of the players. Post hoc inspection of the footage was undertaken to count the number of possessions and the number and quality of disposals. In comparison to 'on-side' games, 'off-side' games had a greater number of involvements ("touches"), passes, and effective passes. However, the cognitive demands of 'on-side' games were greater than 'off-side' games. 'Off-side' games resulted in a greater total distance covered, greater distance covered in mild and moderate accelerations, and greater distance covered in low, moderate, and high-velocity efforts. There were also a greater number of short duration recovery periods between efforts in 'off-side' games. The results of this study demonstrate that 'off-side' games provide greater physiological and skill demands than 'on-side' games. 'Off-side' games may provide a practical alternative to 'on-side' games for the development of skill and fitness in elite rugby league players.
EPA'S PHOTOVOLTAIC DEMAND-SIDE MANAGEMENT COST-SHARED DEMONSTRATIONS
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
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...
Demand-side policies to encourage the use of generic medicines: an overview.
Dylst, Pieter; Vulto, Arnold; Simoens, Steven
2013-02-01
Demand-side policies to encourage the use of generic medicines are important to increase their use. A plethora of different demand-side policies has already been initiated by European governments, thereby targeting physicians, pharmacists and patients. This review aims to give an overview of the different demand-side policies which governments have at their disposal and to evaluate their impact on the use of generic medicines. Positive knowledge and perceptions of physicians, pharmacists and patients of generic medicines are necessary prerequisites to increase the use of generic medicines and governments should initiate policies to achieve this. These policies should be combined with policies to increase their financial responsibility to the healthcare system and policies to facilitate the prescribing of generic medicines.
NASA Astrophysics Data System (ADS)
Abad Lopez, Carlos Adrian
Current electricity infrastructure is being stressed from several directions -- high demand, unreliable supply, extreme weather conditions, accidents, among others. Infrastructure planners have, traditionally, focused on only the cost of the system; today, resilience and sustainability are increasingly becoming more important. In this dissertation, we develop computational tools for efficiently managing electricity resources to help create a more reliable and sustainable electrical grid. The tools we present in this work will help electric utilities coordinate demand to allow the smooth and large scale integration of renewable sources of energy into traditional grids, as well as provide infrastructure planners and operators in developing countries a framework for making informed planning and control decisions in the presence of uncertainty. Demand-side management is considered as the most viable solution for maintaining grid stability as generation from intermittent renewable sources increases. Demand-side management, particularly demand response (DR) programs that attempt to alter the energy consumption of customers either by using price-based incentives or up-front power interruption contracts, is more cost-effective and sustainable in addressing short-term supply-demand imbalances when compared with the alternative that involves increasing fossil fuel-based fast spinning reserves. An essential step in compensating participating customers and benchmarking the effectiveness of DR programs is to be able to independently detect the load reduction from observed meter data. Electric utilities implementing automated DR programs through direct load control switches are also interested in detecting the reduction in demand to efficiently pinpoint non-functioning devices to reduce maintenance costs. We develop sparse optimization methods for detecting a small change in the demand for electricity of a customer in response to a price change or signal from the utility, dynamic learning methods for scheduling the maintenance of direct load control switches whose operating state is not directly observable and can only be inferred from the metered electricity consumption, and machine learning methods for accurately forecasting the load of hundreds of thousands of residential, commercial and industrial customers. These algorithms have been implemented in the software system provided by AutoGrid, Inc., and this system has helped several utilities in the Pacific Northwest, Oklahoma, California and Texas, provide more reliable power to their customers at significantly reduced prices. Providing power to widely spread out communities in developing countries using the conventional power grid is not economically feasible. The most attractive alternative source of affordable energy for these communities is solar micro-grids. We discuss risk-aware robust methods to optimally size and operate solar micro-grids in the presence of uncertain demand and uncertain renewable generation. These algorithms help system operators to increase their revenue while making their systems more resilient to inclement weather conditions.
Energy Sustainability and the Green Campus.
ERIC Educational Resources Information Center
Simpson, Walter
2003-01-01
Discusses the importance of campus energy sustainability, explaining that both demand- and supply-side strategies are required. Suggests that on the demand side, an aggressive campus energy conservation program can reduce campus energy consumption by 30 percent or more. Asserts that addressing the supply side of the energy equation means shifting…
Small-sided games in team sports training: a brief review.
Halouani, Jamel; Chtourou, Hamdi; Gabbett, Tim; Chaouachi, Anis; Chamari, Karim
2014-12-01
Small-sided games (SSGs) incorporating skills, sport-specific movements, at intensities sufficient to promote aerobic adaptations, are being increasingly implemented in professional team sport environments. Small-sided games are often employed by coaches based on the premise that the greatest training benefits occur when training simulates the specific movement patterns and physiological demands of the sport. At present, there is relatively little information regarding how SSG can best be used to improve physical capacities and technical and tactical skills in team sports. It is possible that with some modifications (e.g., number of players, pitch size, coach encouragement, and wrestling), such games may be physiologically beneficial for athletes with relatively high initial aerobic fitness levels. For instance, it has been shown that 3-a-side soccer SSG resulted in higher intensity (i.e., greater overall distance, less jogging and walking, higher heart rate, and more tackling, dribbling, goal attempts, and passes) than 5-a-side SSG. Likewise, when player numbers were kept constant, a larger playing area increased the intensity of the SSG with a smaller playing area having the opposite effect. It has also been demonstrated that energy expenditure was similar between badminton and volleyball courts, but lower than that obtained in a basketball court. Moreover, it has been demonstrated in rugby that wrestling can increase the physical demands of SSG. Consistent coach encouragement can also increase training intensity, although most rule changes have trivial or no effect on exercise intensity. Further research is required to examine the optimal periodization strategies of SSG training for the long-term development of physiological capacity, technical skill, and tactical proficiency, while also minimizing the associated risk of injuries.
The feedback control cycle as regulator of past and future mineral supply
NASA Astrophysics Data System (ADS)
Wellmer, Friedrich-W.; Dalheimer, Manfred
2012-10-01
Mineral supply is controlled by a feedback mechanism. When there is a shortage of a commodity in a market economy, prices will rise, triggering this mechanism. The expectation of high financial returns will encourage inventiveness and creativity in the quest for new solutions. On the supply side, for primary resources, the appropriate response is to cut losses in the mining process, to lower the cut-off grade, to improve recoveries in the beneficiation and smelting processes, to expand existing production facilities, and to discover and bring into production new deposits. For secondary resources, the key to increasing the supply lies in improving recycling rates by better technology, reprocessing lower-grade scrap which becomes economic because of increased prices, and reducing downgrading to optimize the usefulness of secondary materials. On the demand side, implementation of new and more efficient processes, development of substitution technologies, material savings, and the invention of entirely new technologies that fulfill the same function without the need of using the scarce and suddenly more expensive material are effective reactions to a price rise. The effectiveness of this self-regulating mechanism can be shown by examples of historical price peaks of metals, such as Mo, Co, and Ta, and the current rare earth elements peak. Concerning supply from secondary resources, a model is developed in order to determine how far the supply from this resource domain can be achieved and how the recycling rate is influenced by growth rate and lifetime. The feedback control cycle of mineral supply is influenced on the demand side by ever shorter life cycles, by products getting more complex with ever more elements involved in their production, and by an increase in element dispersion. All these factors have an immediate effect on the feasibility of sourcing raw materials from the technosphere. The supply side of primary materials is influenced by increasing lead times for new production and by relatively low flexibility in responding to changing demand.
NASA Astrophysics Data System (ADS)
Liu, Yiqun; Zhou, Pengcheng; Zeng, Ming; Chen, Songsong
2018-01-01
With the gradual reform of the electricity market, the power sale side liberalization has become the focus of attention as the key task of reform. The open power market provides a good environment for DR (Demand Response). It is of great significance to research the simulation requirements and business architecture of ADR (Automatic Demand Response) in power sale side market liberalization. Firstly, this paper analyzes the simulation requirements of ADR. Secondly, it analyzes the influence factors that the business development of ADR from five aspects after power sale side market liberalization. Finally, Based on ADR technology support system, the business architecture of ADR after power sale side market liberalization is constructed.
Hernández, Luis; Baladrón, Carlos; Aguiar, Javier M.; Calavia, Lorena; Carro, Belén; Sánchez-Esguevillas, Antonio; Cook, Diane J.; Chinarro, David; Gómez, Jorge
2012-01-01
One of the main challenges of today's society is the need to fulfill at the same time the two sides of the dichotomy between the growing energy demand and the need to look after the environment. Smart Grids are one of the answers: intelligent energy grids which retrieve data about the environment through extensive sensor networks and react accordingly to optimize resource consumption. In order to do this, the Smart Grids need to understand the existing relationship between energy demand and a set of relevant climatic variables. All smart “systems” (buildings, cities, homes, consumers, etc.) have the potential to employ their intelligence for self-adaptation to climate conditions. After introducing the Smart World, a global framework for the collaboration of these smart systems, this paper presents the relationship found at experimental level between a range of relevant weather variables and electric power demand patterns, presenting a case study using an agent-based system, and emphasizing the need to consider this relationship in certain Smart World (and specifically Smart Grid and microgrid) applications.
Policies to Enhance Prescribing Efficiency in Europe: Findings and Future Implications
Godman, Brian; Shrank, William; Andersen, Morten; Berg, Christian; Bishop, Iain; Burkhardt, Thomas; Garuoliene, Kristina; Herholz, Harald; Joppi, Roberta; Kalaba, Marija; Laius, Ott; Lonsdale, Julie; Malmström, Rickard E.; Martikainen, Jaana E.; Samaluk, Vita; Sermet, Catherine; Schwabe, Ulrich; Teixeira, Inês; Tilson, Lesley; Tulunay, F. Cankat; Vlahović-Palčevski, Vera; Wendykowska, Kamila; Wettermark, Bjorn; Zara, Corinne; Gustafsson, Lars L.
2010-01-01
Introduction: European countries need to learn from each other to address unsustainable increases in pharmaceutical expenditures. Objective: To assess the influence of the many supply and demand-side initiatives introduced across Europe to enhance prescribing efficiency in ambulatory care. As a result provide future guidance to countries. Methods: Cross national retrospective observational study of utilization (DDDs – defined daily doses) and expenditure (Euros and local currency) of proton pump inhibitors (PPIs) and statins among 19 European countries and regions principally from 2001 to 2007. Demand-side measures categorized under the “4Es” – education engineering, economics, and enforcement. Results: Instigating supply side initiatives to lower the price of generics combined with demand-side measures to enhance their prescribing is important to maximize prescribing efficiency. Just addressing one component will limit potential efficiency gains. The influence of demand-side reforms appears additive, with multiple initiatives typically having a greater influence on increasing prescribing efficiency than single measures apart from potentially “enforcement.” There are also appreciable differences in expenditure (€/1000 inhabitants/year) between countries. Countries that have not introduced multiple demand side measures to counteract commercial pressures to enhance the prescribing of generics have seen considerably higher expenditures than those that have instigated a range of measures. Conclusions: There are considerable opportunities for European countries to enhance their prescribing efficiency, with countries already learning from each other. The 4E methodology allows European countries to concisely capture the range of current demand-side measures and plan for the future knowing that initiatives can be additive to further enhance their prescribing efficiency. PMID:21833180
Intelligent demand side management of residential building energy systems
NASA Astrophysics Data System (ADS)
Sinha, Maruti N.
Advent of modern sensing technologies, data processing capabilities and rising cost of energy are driving the implementation of intelligent systems in buildings and houses which constitute 41% of total energy consumption. The primary motivation has been to provide a framework for demand-side management and to improve overall reliability. The entire formulation is to be implemented on NILM (Non-Intrusive Load Monitoring System), a smart meter. This is going to play a vital role in the future of demand side management. Utilities have started deploying smart meters throughout the world which will essentially help to establish communication between utility and consumers. This research is focused on investigation of a suitable thermal model of residential house, building up control system and developing diagnostic and energy usage forecast tool. The present work has considered measurement based approach to pursue. Identification of building thermal parameters is the very first step towards developing performance measurement and controls. The proposed identification technique is PEM (Prediction Error Method) based, discrete state-space model. The two different models have been devised. First model is focused toward energy usage forecast and diagnostics. Here one of the novel idea has been investigated which takes integral of thermal capacity to identify thermal model of house. The purpose of second identification is to build up a model for control strategy. The controller should be able to take into account the weather forecast information, deal with the operating point constraints and at the same time minimize the energy consumption. To design an optimal controller, MPC (Model Predictive Control) scheme has been implemented instead of present thermostatic/hysteretic control. This is a receding horizon approach. Capability of the proposed schemes has also been investigated.
Two-stage collaborative global optimization design model of the CHPG microgrid
NASA Astrophysics Data System (ADS)
Liao, Qingfen; Xu, Yeyan; Tang, Fei; Peng, Sicheng; Yang, Zheng
2017-06-01
With the continuous developing of technology and reducing of investment costs, renewable energy proportion in the power grid is becoming higher and higher because of the clean and environmental characteristics, which may need more larger-capacity energy storage devices, increasing the cost. A two-stage collaborative global optimization design model of the combined-heat-power-and-gas (abbreviated as CHPG) microgrid is proposed in this paper, to minimize the cost by using virtual storage without extending the existing storage system. P2G technology is used as virtual multi-energy storage in CHPG, which can coordinate the operation of electric energy network and natural gas network at the same time. Demand response is also one kind of good virtual storage, including economic guide for the DGs and heat pumps in demand side and priority scheduling of controllable loads. Two kinds of storage will coordinate to smooth the high-frequency fluctuations and low-frequency fluctuations of renewable energy respectively, and achieve a lower-cost operation scheme simultaneously. Finally, the feasibility and superiority of proposed design model is proved in a simulation of a CHPG microgrid.
Supply-side and demand-side policies for biosimilars: an overview in 10 European member states.
Rémuzat, Cécile; Kapuśniak, Anna; Caban, Aleksandra; Ionescu, Dan; Radière, Guerric; Mendoza, Cyril; Toumi, Mondher
2017-01-01
This study aimed to provide an overview of biosimilar policies in 10 EU MSs. Methods : Ten EU MS pharmaceutical markets (Belgium, France, Germany, Greece, Hungary, Italy, Poland, Spain, Sweden, and the UK) were selected. A comprehensive literature review was performed to identify supply-side and demand-side policies in place in the selected countries. Results : Supply-side policies for biosimilars commonly include price linkage, price re-evaluation, and tendering; the use of internal or external reference pricing varies between countries; health technology assessment is conducted in six countries. Regarding demand-side policies, pharmaceutical prescription budgets or quotas and monitoring of prescriptions (with potential financial incentives or penalties) are in place in eight and in seven countries respectively. Switching is generally allowed, but is solely the physician's responsibility. Automatic substitution is not recommended, or even forbidden, in most EU MSs. Prescription conditions or guidelines that apply to biosimilars are established in nearly all surveyed EU MSs. Conclusions : Important heterogeneity in policies on biosimilars was seen between (and even within) selected countries, which may partly explain variations in biosimilar uptake. Supply-side policies targeting price have been reported to limit biosimilar penetration in the long term, despite short-term savings, while demand-side policies are considered to positively impact uptake.
Supply-side and demand-side policies for biosimilars: an overview in 10 European member states
Rémuzat, Cécile; Kapuśniak, Anna; Caban, Aleksandra; Ionescu, Dan; Radière, Guerric; Mendoza, Cyril; Toumi, Mondher
2017-01-01
ABSTRACT Objective: This study aimed to provide an overview of biosimilar policies in 10 EU MSs. Methods: Ten EU MS pharmaceutical markets (Belgium, France, Germany, Greece, Hungary, Italy, Poland, Spain, Sweden, and the UK) were selected. A comprehensive literature review was performed to identify supply-side and demand-side policies in place in the selected countries. Results: Supply-side policies for biosimilars commonly include price linkage, price re-evaluation, and tendering; the use of internal or external reference pricing varies between countries; health technology assessment is conducted in six countries. Regarding demand-side policies, pharmaceutical prescription budgets or quotas and monitoring of prescriptions (with potential financial incentives or penalties) are in place in eight and in seven countries respectively. Switching is generally allowed, but is solely the physician’s responsibility. Automatic substitution is not recommended, or even forbidden, in most EU MSs. Prescription conditions or guidelines that apply to biosimilars are established in nearly all surveyed EU MSs. Conclusions: Important heterogeneity in policies on biosimilars was seen between (and even within) selected countries, which may partly explain variations in biosimilar uptake. Supply-side policies targeting price have been reported to limit biosimilar penetration in the long term, despite short-term savings, while demand-side policies are considered to positively impact uptake. PMID:28740617
NASA Astrophysics Data System (ADS)
Tegen, Suzanne Isabel Helmholz
This dissertation introduces new techniques for calculating and comparing statewide economic impacts from new coal, natural gas and wind power plants, as well as from demand-side management programs. The impetus for this work was two-fold. First, reviews of current literature and projects revealed that there was no standard way to estimate statewide economic impacts from new supply- and demand-side electricity options. Second, decision-makers who were interviewed stated that they were overwhelmed with data in general, but also lacked enough specific information about economic development impacts to their states from electricity, to make informed choices. This dissertation includes chapters on electricity decision-making and on economic impacts from supply and demand. The supply chapter compares different electricity options in three states which vary in natural resource content: Arizona, Colorado and Michigan. To account for differing capacity factors, resources are compared on a per-megawatt-hour basis. The calculations of economic impacts from new supply include: materials and labor for construction, operations, maintenance, fuel extraction, fuel transport, as well as property tax, financing and landowner revenues. The demand-side chapter compares residential, commercial and industrial programs in Iowa. Impact calculations include: incremental labor and materials for program planning, installation and operations, as well as sales taxes and electricity saved. Results from supply-side calculations in the three states analyzed indicate that adding new wind power can have a greater impact to a state's economy than adding new gas or coal power due to resource location, taxes and infrastructure. Additionally, demand-side management programs have a higher relative percentage of in-state dollar flow than supply-side solutions, though demand-side programs typically involve fewer MWh and dollars than supply-side generation. Methods for this dissertation include researching existing models and data, gathering new data and interviews with industry representatives and policy makers. The new techniques are important for decision-makers, utilities, energy advocates and others who are concerned with economic development and in-state dollar flows from new electricity decisions.
Wang, Tiancai; He, Xing; Huang, Tingwen; Li, Chuandong; Zhang, Wei
2017-09-01
The economic emission dispatch (EED) problem aims to control generation cost and reduce the impact of waste gas on the environment. It has multiple constraints and nonconvex objectives. To solve it, the collective neurodynamic optimization (CNO) method, which combines heuristic approach and projection neural network (PNN), is attempted to optimize scheduling of an electrical microgrid with ten thermal generators and minimize the plus of generation and emission cost. As the objective function has non-derivative points considering valve point effect (VPE), differential inclusion approach is employed in the PNN model introduced to deal with them. Under certain conditions, the local optimality and convergence of the dynamic model for the optimization problem is analyzed. The capability of the algorithm is verified in a complicated situation, where transmission loss and prohibited operating zones are considered. In addition, the dynamic variation of load power at demand side is considered and the optimal scheduling of generators within 24 h is described. Copyright © 2017 Elsevier Ltd. All rights reserved.
Optimizing Aggregation Scenarios for Integrating Renewable Energy into the U.S. Electric Grid
NASA Astrophysics Data System (ADS)
Corcoran, B. A.; Jacobson, M. Z.
2010-12-01
This study is an analysis of 2006 and 2007 electric load data, wind speed and solar irradiance data, and existing hydroelectric, geothermal, and other power plant data to quantify benefits of aggregating clean electric power from various Federal Energy Regulatory Commission (FERC) regions in the contiguous United States. First, various time series, statistics, and probability methods are applied to the electric load data to determine if there are any desirable demand-side results—specifically reducing variability and/or coincidence of peak events, which could reduce the amount of required carbon-based generators—in combining the electricity demands from geographically and temporally diverse areas. Second, an optimization algorithm is applied to determine the least-cost portfolio of energy resources to meet the electric load for a range of renewable portfolio standards (RPS’s) for each FERC region and for various aggregation scenarios. Finally, the installed capacities, ramp rates, standard deviation, and corresponding generator requirements from these optimization test runs are compared against the transmission requirements to determine the most economical organizational structure of the contiguous U.S. electric grid. Ideally, results from this study will help to justify and identify a possible structure of a federal RPS and offer insight into how to best organize regions for transmission planning.
NASA Astrophysics Data System (ADS)
Lee, Allen
The recent natural gas boom has opened much discussion about the potential of natural gas and specifically Liquefied Natural Gas (LNG) in the United States transportation sector. The switch from diesel to natural gas vehicles would reduce foreign dependence on oil, spur domestic economic growth, and potentially reduce greenhouse gas emissions. LNG provides the most potential for the medium to heavy-duty vehicle market partially due to unstable oil prices and stagnant natural gas prices. As long as the abundance of unconventional gas in the United States remains cheap, fuel switching to natural gas could provide significant cost savings for long haul freight industry. Amid a growing LNG station network and ever increasing demand for freight movement, LNG heavy-duty truck sales are less than anticipated and the industry as a whole is less economic than expected. In spite of much existing and mature natural gas infrastructure, the supply chain for LNG is different and requires explicit and careful planning. This thesis proposes research to explore the claim that the largest obstacle to widespread LNG market penetration is sub-optimal infrastructure planning. No other study we are aware of has explicitly explored the LNG transportation fuel supply chain for heavy-duty freight trucks. This thesis presents a novel methodology that links a network infrastructure optimization model (represents supply side) with a vehicle stock and economic payback model (represents demand side). The model characterizes both a temporal and spatial optimization model of future LNG transportation fuel supply chains in the United States. The principal research goal is to assess the economic feasibility of the current LNG transportation fuel industry and to determine an optimal pathway to achieve ubiquitous commercialization of LNG vehicles in the heavy-duty transport sector. The results indicate that LNG is not economic as a heavy-duty truck fuel until 2030 under current market conditions unless a significant station capital subsidy, upwards of 50 percent and even then it might not be enough. However, a doubling of LNG truck demand will initialize network commercialization in the modeling base year, 2012 (the same year Clean Energy Corp. launched their national LNG network) in California and then gradually establish in other hotspot regions in Mid-West and Mid-Atlantic throughout the time horizon. The model shows that trucking routes in California are highly commercial due to high traffic volume and regional advantages. The model can be used by industry to inform necessary policies and to plan future infrastructure deployment along trucking routes that are likely to provide the highest returns.
Altruism in the "Market" for Giving and Receiving: A Case of Higher Education.
ERIC Educational Resources Information Center
Yoo, Jang H.; Harrison, William B.
1989-01-01
Examines donations to colleges as an outcome of simultaneously solving supply and demand functions. Donors demand attention and prestige supplied by college fund raisers. Using data from 13 colleges, this econometric study shows that the demand side has a unitary elasticity concerning per person donations, while the supply side seems inelastic.…
UNEQUAL RISK: COMBAT OCCUPATIONS IN THE VOLUNTEER MILITARY
MacLEAN, ALAIR; PARSONS, NICHOLAS L.
2011-01-01
This study evaluates the characteristics of the men who served in the volunteer military in combat occupations. It examines whether these characteristics stem from supply-side or demand-side decisions, or reflect class bias. The findings suggest that, on the supply side, men who had greater academic abilities were more likely to go to college, thereby avoiding military service and the possibility of serving in a combat occupation. On the demand side, the armed forces were more likely to exclude men with lower academic abilities but were more likely to assign such men in the military to combat occupations. Net of the impacts of these supply-side and demand-side decisions, men who served in combat occupations still differed from those who did not in terms of their family background. The impact of family background was stronger on entering the military than on being assigned to combat occupations once in the military. PMID:21691446
Four measures of transportation's economic importance
DOT National Transportation Integrated Search
2000-04-01
As a commodity, transportation has a supply side and a demand side. Unlike many other commodities, however, transportation's supply and demand overlap extensively. A significant portion of transportation : is provided by consumers for their own use. ...
Demand Side Management: An approach to peak load smoothing
NASA Astrophysics Data System (ADS)
Gupta, Prachi
A preliminary national-level analysis was conducted to determine whether Demand Side Management (DSM) programs introduced by electric utilities since 1992 have made any progress towards their stated goal of reducing peak load demand. Estimates implied that DSM has a very small effect on peak load reduction and there is substantial regional and end-user variability. A limited scholarly literature on DSM also provides evidence in support of a positive effect of demand response programs. Yet, none of these studies examine the question of how DSM affects peak load at the micro-level by influencing end-users' response to prices. After nearly three decades of experience with DSM, controversy remains over how effective these programs have been. This dissertation considers regional analyses that explore both demand-side solutions and supply-side interventions. On the demand side, models are estimated to provide in-depth evidence of end-user consumption patterns for each North American Electric Reliability Corporation (NERC) region, helping to identify sectors in regions that have made a substantial contribution to peak load reduction. The empirical evidence supports the initial hypothesis that there is substantial regional and end-user variability of reductions in peak demand. These results are quite robust in rapidly-urbanizing regions, where air conditioning and lighting load is substantially higher, and regions where the summer peak is more pronounced than the winter peak. It is also evident from the regional experiences that active government involvement, as shaped by state regulations in the last few years, has been successful in promoting DSM programs, and perhaps for the same reason we witness an uptick in peak load reductions in the years 2008 and 2009. On the supply side, we estimate the effectiveness of DSM programs by analyzing the growth of capacity margin with the introduction of DSM programs. The results indicate that DSM has been successful in offsetting the need for additional production capacity by the means of demand response measures, but the success is limited to only a few regions. The rate of progress in the future will depend on a wide range of improved technologies and a continuous government monitoring for successful adoption of demand response programs to manage growing energy demand.
Murray, Susan F; Hunter, Benjamin M; Bisht, Ramila; Ensor, Tim; Bick, Debra
2012-01-01
In many countries financing for health services has traditionally been disbursed directly from governmental and non-governmental funding agencies to providers of services: the 'supply-side' of healthcare markets. Demand-side financing offers a supplementary model in which some funds are instead channelled through, or to, prospective users. In this review we considered evidence on five forms of demand-side financing that have been used to promote maternal health in developing countries: OBJECTIVES: The overall review objective was to assess the effects of demand-side financing interventions on maternal health service utilisation and on maternal health outcomes in low- and middle-income countries. Broader effects on perinatal and infant health, the situation of underprivileged women and the health care system were also assessed. This review considered poor, rural or socially excluded women of all ages who were either pregnant or within 42 days of the conclusion of pregnancy, the limit for postnatal care as defined by the World Health Organization. The review also considered the providers of services.The intervention of interest was any programme that incorporated demand-side financing as a mechanism to increase the consumption of goods and services that could impact on maternal health outcomes. This included the direct consumption of maternal health care goods and services as well as related 'merit goods' such as improved nutrition. We included systems in which potential users of maternal health services are financially empowered to make restricted decisions on buying maternal health-related goods or services - sometimes known as consumer-led demand-side financing. We also included programmes that provided unconditional cash benefits to pregnant women (for example in the form of maternity allowances), or to families with children under five years of age where there was evidence concerning maternal health outcomes.We aimed to include quantitative studies (experimental, observational and descriptive), qualitative studies (including designs based on phenomenology, grounded theory, ethnography, action research and feminist research), and economic studies (cost-effectiveness, cost-utility and costs studies). The Joanna Briggs Institute methodology for mixed-method systematic reviews was adopted. A three-step systematic search strategy was used to: 1) identify key terms, 2) search bibliographic databases and 3) retrieve additional publications from reference lists and sources of grey literature. Data were extracted from papers included in the review using the standardised data extraction tools for quantitative, qualitative and economic data from the Joanna Briggs Institute System for the Unified Management, Assessment and Review of Information. The quantitative and economic findings are presented in narrative form. Qualitative research findings were pooled using the Joanna Briggs Institute Qualitative Assessment and Review Instrument. This involved the aggregation or synthesis of findings to generate a set of statements that represent that aggregation, through assembling the findings (Level 1 findings), and categorising these findings on the basis of similarity in meaning (Level 2 findings). These categories were then subjected to a meta-synthesis in order to produce a single comprehensive set of synthesised findings (Level 3 findings) that can be used as a basis for evidence-based practice or policy. Seventy-two studies were included in the review. Drawing on work from several continents, many of the included studies were reports and evaluations for relevant government or funding agencies and represented important lesson-learning about implementation issues. However, fewer than half were published in peer reviewed journals and few were of high research quality.For three modes of demand-side financing (conditional cash transfers, payments to offset costs of access to maternal healthcare, and vouchers for maternity services) we found evidence relevant to review questions on the utilisation of maternal health services, barriers to the provision of demand-side financing and supply-side preconditions to implementing demand-side financing schemes. There was insufficient evidence to provide comprehensive answers for review questions on the effect of demand-side financing interventions on maternal, perinatal and infant health outcomes and on the social and financial situation of underprivileged women. There was also insufficient evidence on the cost-effectiveness of demand-side financing interventions and preconditions for sustainability and scale-up of demand-side financing schemes.Salient recommendations for policymakers regarding demand-side financing for maternal health derived from the current evidence are:There is a pressing need for large, robust studies on the short- and longer-term impact of demand-side financing on maternal and infant mortality and morbidity, which should also reflect 'good practice' indicators such as the uptake and duration of exclusive breastfeeding and compliance with infant immunisation programmes. It is also important that the impact on outcomes of subsequent pregnancies is evaluated. Moderate and large-sized demand-side financing programmes that have recently or will soon be scaled up, such as those in Kenya, Uganda and Bangladesh, represent the most obvious sites for such evaluations, and lessons may be learnt from Mexico's PROGRESA/ Oportunidades about how to establish a well-embedded monitoring and rigorous evaluation structure.Other important areas that require further study include.
A 'demand side' estimate of the dollar value of the cannabis black market in New Zealand.
Wilkins, Chris; Bhatta, Krishna; Casswell, Sally
2002-06-01
The dollar value of an illicit drug market is an important statistic in drug policy analysis. It can be used to illustrate the scale of the trade in a drug; evaluate its impact on a local community or nation; provide an indication of the level of criminality related to a drug; and can inform discussions of future drug policy options. This paper calculates the first ever demand side estimates of the New Zealand cannabis black market. The estimates produced are calculated using cannabis consumption data from the Alcohol & Public Health Research Unit's (APHRU) 1998 National Drug Survey. The wholesale value of the market is estimated to be 81.3-104.6 million dollars a year, and the retail value of the market is estimated to be 131.3-168.9 million dollars a year. These demand side estimates are much lower than the existing supply side estimates of the market calculated using police seizures of cannabis plants. The retail figure is four times lower than the lowest national supply side estimate (636 million dollars) and seven times lower than the highest national supply side estimate (1.27 billion dollars). The demand side estimates suggest a much smaller cannabis economy to fuel organized criminal activity in New Zealand than previous estimates implied.
A network approach to decentralized coordination of energy production-consumption grids.
Omodei, Elisa; Arenas, Alex
2018-01-01
Energy grids are facing a relatively new paradigm consisting in the formation of local distributed energy sources and loads that can operate in parallel independently from the main power grid (usually called microgrids). One of the main challenges in microgrid-like networks management is that of self-adapting to the production and demands in a decentralized coordinated way. Here, we propose a stylized model that allows to analytically predict the coordination of the elements in the network, depending on the network topology. Surprisingly, almost global coordination is attained when users interact locally, with a small neighborhood, instead of the obvious but more costly all-to-all coordination. We compute analytically the optimal value of coordinated users in random homogeneous networks. The methodology proposed opens a new way of confronting the analysis of energy demand-side management in networked systems.
Can the generic antiretroviral industry support access to a universal antiretroviral regimen?
Amole, Carolyn D; Middlecote, Caroline; Prabhu, Vineet R; Kumarasamy, N
2017-07-01
The generic antiretroviral (ARV) industry played a critical role in the massive scale-up of HIV treatment in low-income and middle-income countries since 2000. As the global community looks ahead to a universal antiretroviral regimen, this article considers the industry's role in supporting universal access to affordable, simpler, more durable, and tolerable HIV treatment regimens. Generic manufacturers made treatment scale-up in low-income and middle-income countries possible through reducing prices, combining molecules from different originator companies to develop optimal fixed-dose combinations, and investing in production capacity to meet escalating demand. Achieving scale-up of a universal regimen will require continued partnership in these areas. Collaboration on the demand and supply sides of the ARV marketplace will be required to foster a healthy and sustainable marketplace for new regimens. This includes clear priority setting from the global treatment community on priority products; predictable demand; regulatory prioritization of optimal products; effective tendering and procurement practices that enable multiple suppliers to participate in the market; coordinated product introduction efforts between Ministries of Health, partners, and civil society; and transparency from both buyers and suppliers to promote and monitor supply security. New regimens will benefit people living with HIV, as well as buyers and generic suppliers, by maximizing existing production capacity and treatment budgets to reach the 90-90-90 goals.
Modeling and optimization of a hybrid solar combined cycle (HYCS)
NASA Astrophysics Data System (ADS)
Eter, Ahmad Adel
2011-12-01
The main objective of this thesis is to investigate the feasibility of integrating concentrated solar power (CSP) technology with the conventional combined cycle technology for electric generation in Saudi Arabia. The generated electricity can be used locally to meet the annual increasing demand. Specifically, it can be utilized to meet the demand during the hours 10 am-3 pm and prevent blackout hours, of some industrial sectors. The proposed CSP design gives flexibility in the operation system. Since, it works as a conventional combined cycle during night time and it switches to work as a hybrid solar combined cycle during day time. The first objective of the thesis is to develop a thermo-economical mathematical model that can simulate the performance of a hybrid solar-fossil fuel combined cycle. The second objective is to develop a computer simulation code that can solve the thermo-economical mathematical model using available software such as E.E.S. The developed simulation code is used to analyze the thermo-economic performance of different configurations of integrating the CSP with the conventional fossil fuel combined cycle to achieve the optimal integration configuration. This optimal integration configuration has been investigated further to achieve the optimal design of the solar field that gives the optimal solar share. Thermo-economical performance metrics which are available in the literature have been used in the present work to assess the thermo-economic performance of the investigated configurations. The economical and environmental impact of integration CSP with the conventional fossil fuel combined cycle are estimated and discussed. Finally, the optimal integration configuration is found to be solarization steam side in conventional combined cycle with solar multiple 0.38 which needs 29 hectare and LEC of HYCS is 63.17 $/MWh under Dhahran weather conditions.
A novel medical information management and decision model for uncertain demand optimization.
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.
Demand-Side Job Development and System Change.
ERIC Educational Resources Information Center
Gilbride, Dennis; Stensrud, Robert
1999-01-01
Authors discuss demand-side job development as a model for improving and providing rehabilitation services to consumers and employers. It stresses quality employment outcomes, consumer choice and empowerment, and a productive partnership between consumer and counselor. Delineates systemic challenges this model poses to traditional vocational…
Hontelez, Jan A.C.; Chang, Angela Y.; Ogbuoji, Osondu; de Vlas, Sake J.; Bärnighausen, Till; Atun, Rifat
2016-01-01
Objective: We estimated the investment needs, population health gains, and cost-effectiveness of different policy options for scaling-up prevention and treatment of HIV in the 10 countries that currently comprise 80% of all people living with HIV in sub-Saharan Africa (Ethiopia, Kenya, Malawi, Mozambique, Nigeria, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe). Design: We adapted the established STDSIM model to capture the health system dynamics: demand-side and supply-side constraints in the delivery of antiretroviral treatment (ART). Methods: We compared different scenarios of supply-side (i.e. health system capacity) and demand-side (i.e. health seeking behavior) constraints, and determined the impact of changing guidelines to ART eligibility at any CD4+ cell count within these constraints. Results: Continuing current scale-up would require US$178 billion by 2050. Changing guidelines to ART at any CD4+ cell count is cost-effective under all constraints tested in the model, especially in demand-side constrained health systems because earlier initiation prevents loss-to-follow-up of patients not yet eligible. Changing guidelines under current demand-side constraints would avert 1.8 million infections at US$208 per life-year saved. Conclusion: Treatment eligibility at any CD4+ cell count would be cost-effective, even under health system constraints. Excessive loss-to-follow-up and mortality in patients not eligible for treatment can be avoided by changing guidelines in demand-side constrained systems. The financial obligation for sustaining the AIDS response in sub-Saharan Africa over the next 35 years is substantial and requires strong, long-term commitment of policy-makers and donors to continue to allocate substantial parts of their budgets. PMID:27367487
Hontelez, Jan A C; Chang, Angela Y; Ogbuoji, Osondu; de Vlas, Sake J; Bärnighausen, Till; Atun, Rifat
2016-09-24
We estimated the investment needs, population health gains, and cost-effectiveness of different policy options for scaling-up prevention and treatment of HIV in the 10 countries that currently comprise 80% of all people living with HIV in sub-Saharan Africa (Ethiopia, Kenya, Malawi, Mozambique, Nigeria, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe). We adapted the established STDSIM model to capture the health system dynamics: demand-side and supply-side constraints in the delivery of antiretroviral treatment (ART). We compared different scenarios of supply-side (i.e. health system capacity) and demand-side (i.e. health seeking behavior) constraints, and determined the impact of changing guidelines to ART eligibility at any CD4 cell count within these constraints. Continuing current scale-up would require US$178 billion by 2050. Changing guidelines to ART at any CD4 cell count is cost-effective under all constraints tested in the model, especially in demand-side constrained health systems because earlier initiation prevents loss-to-follow-up of patients not yet eligible. Changing guidelines under current demand-side constraints would avert 1.8 million infections at US$208 per life-year saved. Treatment eligibility at any CD4 cell count would be cost-effective, even under health system constraints. Excessive loss-to-follow-up and mortality in patients not eligible for treatment can be avoided by changing guidelines in demand-side constrained systems. The financial obligation for sustaining the AIDS response in sub-Saharan Africa over the next 35 years is substantial and requires strong, long-term commitment of policy-makers and donors to continue to allocate substantial parts of their budgets.
A network approach to decentralized coordination of energy production-consumption grids
Arenas, Alex
2018-01-01
Energy grids are facing a relatively new paradigm consisting in the formation of local distributed energy sources and loads that can operate in parallel independently from the main power grid (usually called microgrids). One of the main challenges in microgrid-like networks management is that of self-adapting to the production and demands in a decentralized coordinated way. Here, we propose a stylized model that allows to analytically predict the coordination of the elements in the network, depending on the network topology. Surprisingly, almost global coordination is attained when users interact locally, with a small neighborhood, instead of the obvious but more costly all-to-all coordination. We compute analytically the optimal value of coordinated users in random homogeneous networks. The methodology proposed opens a new way of confronting the analysis of energy demand-side management in networked systems. PMID:29364962
Improving piezo actuators for nanopositioning tasks
NASA Astrophysics Data System (ADS)
Seeliger, Martin; Gramov, Vassil; Götz, Bernt
2018-02-01
In recent years, numerous applications emerged on the market with seemingly contradicting demands. On one side, the structure size decreased while on the other side, the overall sample size and speed of operation increased. Although the principle usage of piezoelectric positioning solutions has become a standard in the field of micro- and nanopositioning, surface inspection and manipulation, piezosystem jena now enhanced the performance beyond simple control loop tuning and actuator design. In automated manufacturing machines, a given signal has to be tracked fast and precise. However, control systems naturally decrease the ability to follow this signal in real time. piezosystem jena developed a new signal feed forward system bypassing the PID control. This way, we could reduce signal tracking errors by a factor of three compared to a conventionally optimized PID control. Of course, PID-values still have to be adjusted to specific conditions, e.g. changing additional mass, to optimize the performance. This can now be done with a new automatic tuning tool designed to analyze the current setup, find the best fitting configuration, and also gather and display theoretical as well as experimental performance data. Thus, the control quality of a mechanical setup can be improved within a few minutes without the need of external calibration equipment. Furthermore, new mechanical optimization techniques that focus not only on the positioning device, but also take the whole setup into account, prevent parasitic motion down to a few nanometers.
Have complementary therapies demonstrated effectiveness in rheumatoid arthritis?
Fernández-Llanio Comella, Nagore; Fernández Matilla, Meritxell; Castellano Cuesta, Juan Antonio
2016-01-01
In recent decades the treatment of rheumatoid arthritis (RA) has improved thanks to the use of highly effective drugs. However, patients usually require long term therapy, which is not free of side effects. Therefore RA patients often demand complementary medicine, they seek additional sources of relief and/or less side effects. In fact 30-60% of rheumatic patients use some form of complementary medicine. Therefore, from conventional medicine, if we want to optimally treat our patients facilitating communication with them we must know the most commonly used complementary medicines. The aim of this review is to assess, based on published scientific research, what complementary therapies commonly used by patients with RA are effective and safe. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.
Smith, Pete; Haberl, Helmut; Popp, Alexander; Erb, Karl-Heinz; Lauk, Christian; Harper, Richard; Tubiello, Francesco N; de Siqueira Pinto, Alexandre; Jafari, Mostafa; Sohi, Saran; Masera, Omar; Böttcher, Hannes; Berndes, Göran; Bustamante, Mercedes; Ahammad, Helal; Clark, Harry; Dong, Hongmin; Elsiddig, Elnour A; Mbow, Cheikh; Ravindranath, Nijavalli H; Rice, Charles W; Robledo Abad, Carmenza; Romanovskaya, Anna; Sperling, Frank; Herrero, Mario; House, Joanna I; Rose, Steven
2013-08-01
Feeding 9-10 billion people by 2050 and preventing dangerous climate change are two of the greatest challenges facing humanity. Both challenges must be met while reducing the impact of land management on ecosystem services that deliver vital goods and services, and support human health and well-being. Few studies to date have considered the interactions between these challenges. In this study we briefly outline the challenges, review the supply- and demand-side climate mitigation potential available in the Agriculture, Forestry and Other Land Use AFOLU sector and options for delivering food security. We briefly outline some of the synergies and trade-offs afforded by mitigation practices, before presenting an assessment of the mitigation potential possible in the AFOLU sector under possible future scenarios in which demand-side measures codeliver to aid food security. We conclude that while supply-side mitigation measures, such as changes in land management, might either enhance or negatively impact food security, demand-side mitigation measures, such as reduced waste or demand for livestock products, should benefit both food security and greenhouse gas (GHG) mitigation. Demand-side measures offer a greater potential (1.5-15.6 Gt CO2 -eq. yr(-1) ) in meeting both challenges than do supply-side measures (1.5-4.3 Gt CO2 -eq. yr(-1) at carbon prices between 20 and 100 US$ tCO2 -eq. yr(-1) ), but given the enormity of challenges, all options need to be considered. Supply-side measures should be implemented immediately, focussing on those that allow the production of more agricultural product per unit of input. For demand-side measures, given the difficulties in their implementation and lag in their effectiveness, policy should be introduced quickly, and should aim to codeliver to other policy agenda, such as improving environmental quality or improving dietary health. These problems facing humanity in the 21st Century are extremely challenging, and policy that addresses multiple objectives is required now more than ever. © 2013 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Radziszewska, Weronika; Nahorski, Zbigniew
An Energy Management System (EMS) for a small microgrid is presented, with both demand and production side management. The microgrid is equipped with renewable and controllable power sources (like a micro gas turbine), energy storage units (batteries and flywheels). Energy load is partially scheduled to avoid extreme peaks of power demand and to possibly match forecasted energy supply from the renewable power sources. To balance the energy in the network on line, a multiagent system is used. Intelligent agents of each device are proactively acting towards balancing the energy in the network, and at the same time optimizing the cost of operation of the whole system. A semi-market mechanism is used to match a demand and a production of the energy. Simulations show that the time of reaching a balanced state does not exceed 1 s, which is fast enough to let execute proper balancing actions, e.g. change an operating point of a controllable energy source. Simulators of sources and consumption devices were implemented in order to carry out exhaustive tests.
Modeling Stationary Lithium-Ion Batteries for Optimization and Predictive Control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baker, Kyri A; Shi, Ying; Christensen, Dane T
Accurately modeling stationary battery storage behavior is crucial to understand and predict its limitations in demand-side management scenarios. In this paper, a lithium-ion battery model was derived to estimate lifetime and state-of-charge for building-integrated use cases. The proposed battery model aims to balance speed and accuracy when modeling battery behavior for real-time predictive control and optimization. In order to achieve these goals, a mixed modeling approach was taken, which incorporates regression fits to experimental data and an equivalent circuit to model battery behavior. A comparison of the proposed battery model output to actual data from the manufacturer validates the modelingmore » approach taken in the paper. Additionally, a dynamic test case demonstrates the effects of using regression models to represent internal resistance and capacity fading.« less
Modeling Stationary Lithium-Ion Batteries for Optimization and Predictive Control: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raszmann, Emma; Baker, Kyri; Shi, Ying
Accurately modeling stationary battery storage behavior is crucial to understand and predict its limitations in demand-side management scenarios. In this paper, a lithium-ion battery model was derived to estimate lifetime and state-of-charge for building-integrated use cases. The proposed battery model aims to balance speed and accuracy when modeling battery behavior for real-time predictive control and optimization. In order to achieve these goals, a mixed modeling approach was taken, which incorporates regression fits to experimental data and an equivalent circuit to model battery behavior. A comparison of the proposed battery model output to actual data from the manufacturer validates the modelingmore » approach taken in the paper. Additionally, a dynamic test case demonstrates the effects of using regression models to represent internal resistance and capacity fading.« less
This study investigated the pollutant emission reduction and demand-side management potential of 16 photovoltaic (PV) systems installed across the U.S. in 1993 and 1994. The project was sponsored by the U.S. Environmental Protection Agency (EPA) and 11 electric utilities. This ar...
Energy Demand-Side Management: New Perspectives for a New Era
ERIC Educational Resources Information Center
Carley, Sanya
2012-01-01
Over the past decade and a half, state governments have assumed greater responsibility over demand-side management (DSM) operations. Whereas DSM programs formerly were initiated primarily by utilities or state public utility commissions, they are now becoming increasingly state-initiated and incentivized through funding mechanisms or…
Urban water infrastructure optimization to reduce environmental impacts and costs.
Lim, Seong-Rin; Suh, Sangwon; Kim, Jung-Hoon; Park, Hung Suck
2010-01-01
Urban water planning and policy have been focusing on environmentally benign and economically viable water management. The objective of this study is to develop a mathematical model to integrate and optimize urban water infrastructures for supply-side planning and policy: freshwater resources and treated wastewater are allocated to various water demand categories in order to reduce contaminants in the influents supplied for drinking water, and to reduce consumption of the water resources imported from the regions beyond a city boundary. A case study is performed to validate the proposed model. An optimal urban water system of a metropolitan city is calculated on the basis of the model and compared to the existing water system. The integration and optimization decrease (i) average concentrations of the influents supplied for drinking water, which can improve human health and hygiene; (ii) total consumption of water resources, as well as electricity, reducing overall environmental impacts; (iii) life cycle cost; and (iv) water resource dependency on other regions, improving regional water security. This model contributes to sustainable urban water planning and policy. 2009 Elsevier Ltd. All rights reserved.
State-of-The-Art of Modeling Methodologies and Optimization Operations in Integrated Energy System
NASA Astrophysics Data System (ADS)
Zheng, Zhan; Zhang, Yongjun
2017-08-01
Rapid advances in low carbon technologies and smart energy communities are reshaping future patterns. Uncertainty in energy productions and demand sides are paving the way towards decentralization management. Current energy infrastructures could not meet with supply and consumption challenges, along with emerging environment and economic requirements. Integrated Energy System(IES) whereby electric power, natural gas, heating couples with each other demonstrates that such a significant technique would gradually become one of main comprehensive and optimal energy solutions with high flexibility, friendly renewables absorption and improving efficiency. In these global energy trends, we summarize this literature review. Firstly the accurate definition and characteristics of IES have been presented. Energy subsystem and coupling elements modeling issues are analyzed. It is pointed out that decomposed and integrated analysis methods are the key algorithms for IES optimization operations problems, followed by exploring the IES market mechanisms. Finally several future research tendencies of IES, such as dynamic modeling, peer-to-peer trading, couple market design, sare under discussion.
Maurer, Jürgen
2009-05-01
Influenza is a serious disease, especially for older people, and incomplete vaccination take-up poses a major public health challenge. On both the side of physicians and patients, there could be promising channels for increasing immunization rates, but no attempt has yet been made to empirically unravel their respective influences. Using exclusion restrictions implied by an economic model of physician-patient interactions, our study quantifies the particular effects of supply and demand on influenza immunization. On the supply side, our estimates highlight the importance of physician agency and physician quality, while a patient's education and health behaviors are key demand side factors.
The report gives results of an investigation into the pollutant emission reduction and demand-side management potential of three photovoltaic (PV) systems installed at Ft. Huachuca, AZ, Ft. Dix, NJ, and Hickam Air Force Base, HI, which began operation between January and July 199...
The report gives results of an investigation of the pollutant emission reduction and demand-side management potential of 16 photovoltaic (PV) systems installed across the U.S. in 1993 and 1994. The investigation was sponsored by the U.S. EPA and 11 electric utilities. The report ...
ERIC Educational Resources Information Center
Kewin, James
2011-01-01
Why are progression rates for Advanced Apprentices so low? Previous research points to a range of supply-side and demand-side barriers. Fundamentally, many employers do not exhibit the sort of demand for higher-level skills that could be used to justify the level of investment required. And, in some cases, employers just don't realise their…
Godman, Brian; Shrank, William; Andersen, Morten; Berg, Christian; Bishop, Iain; Burkhardt, Thomas; Garuoliene, Kristina; Herholz, Harald; Joppi, Roberta; Kalaba, Marija; Laius, Ott; McGinn, Diane; Samaluk, Vita; Sermet, Catherine; Schwabe, Ulrich; Teixeira, Inês; Tilson, Lesley; Tulunay, F Cankat; Vlahović-Palčevski, Vera; Wendykowska, Kamila; Wettermark, Björn; Zara, Corinne; Gustafsson, Lars L
2010-12-01
The aim of this article was to evaluate the influence of different demand-side measures to enhance the prescribing of generics in ambulatory care based on cross-national comparisons. An observational retrospective study was conducted using administrative databases from across Europe, documenting changes in reimbursed utilization and expenditure of different proton pump inhibitors (PPIs) and statins between 2001 and 2007, alongside different reforms to enhance prescribing efficiency. Utilization was converted to defined daily doses (DDDs) and expenditures were converted to euros. Demand-side measures were collated under the '4 Es'--education, engineering, economics and enforcement--to enable comparisons on the nature and intensity of reforms between countries. There were considerable differences in the utilization of generics and patent-protected PPIs and statins among Western European countries. Decreased utilization of omeprazole and simvastatin, alongside increased utilization of esomeprazole, atorvastatin and rosuvastatin, was seen in countries with limited demand-side measures to counteract commercial pressures. Prescribing restrictions, or a combination of education, prescribing targets and financial incentives, had the greatest influence on enhancing the utilization of omeprazole and simvastatin. For example, there was a threefold reduction in the utilization of atorvastatin in Austria following prescribing restrictions. Multiple demand-side interventions generally had a greater influence than single interventions, with the impact appearing additive. Multiple interventions coupled with initiatives to lower prices of generics considerably enhanced prescribing efficiency. This cross-national study has demonstrated considerable variation in the utilization and expenditure of PPIs and statins across Europe, providing opportunities to further improve prescribing efficiency. The '4 Es' do provide an understandable methodology to document and compare the influence of different demand-side measures, with the influence varying by their extent and intensity. Further reforms are essential given current financial pressures. Consequently, further research will concentrate on the potential to develop a scoring system to help predict the possible impact of different demand-side measures on future utilization patterns.
Elmusharaf, Khalifa; Byrne, Elaine; O'Donovan, Diarmuid
2015-09-08
Universal health access will not be achieved unless women are cared for in their own communities and are empowered to take decisions about their own health in a supportive environment. This will only be achieved by community-based demand side interventions for maternal health access. In this review article, we highlight three common strategies to increase demand-side barriers to maternal healthcare access and identify the main challenges that still need to be addressed for these strategies to be effective. Common demand side strategies can be grouped into three categories:(i) Financial incentives/subsidies; (ii) Enhancing patient transfer, and; (iii) Community involvement. The main challenges in assessing the effectiveness or efficacy of these interventions or strategies are the lack of quality evidence on their outcome and impact and interventions not integrated into existing health or community systems. However, what is highlighted in this review and overlooked in most of the published literature on this topic is the lack of knowledge about the context in which these strategies are to be implemented. We suggest three challenges that need to be addressed to create a supportive environment in which these demand-side strategies can effectively improve access to maternal health services. These include: addressing decision-making norms, engaging in intergenerational dialogue, and designing contextually appropriate communication strategies.
Malone, Shane; Collins, Kieran D
2017-06-01
The current study examined the effect that game design modification, goal type, and player numbers on the running performance and physiological demands of small-sided hurling games (SSG). Forty-eight hurling players (age, 25.5 ± 3.2 years; height, 178.9 ± 3.2 cm; body mass, 78.5 ± 4.5 kg) performed 4 types of SSG (possession [P], normal play [NP], regular goals [RG] and small goals [SG]) in 4-a-side, 5-a-side, and 6-a-side formats. Heart rate (Polar Electro Oy) and global positioning system technology (VX Sport, 4-Hz, Lower Hutt) were used to analyze the physical and physiological differences between SSG. Total distance (m), high-speed running distance (m) (≥17 km·h), very-high speed running distance (≥22 km·h) (m), peak and mean velocity (km·h) were analyzed as an indicator of the physical demands of play. The 4-a-side SSG independent of game design and goal type resulted in a significantly higher relative exercise intensity compared with 5-a-side (mean change: 6 ± 2%; p = 0.001; d = 1.9 ± 0.2; large) and 6-a-side SSG independent of game design or goal type (mean change: 12 ± 2%; p = 0.001; d = 2.9 ± 0.8; very large). The 4-a-side SG (619 ± 106-m [419-735-m]) resulted in the highest distance when compared with all PP (mean change: 141 ± 9 m; p = 0.05; d = 1.9 ± 0.3; moderate) and RG (mean change: 119 ± 39 m; p = 0.004; d = 2.1 ± 0.8; large). Similar trends were observed for 5-a-side and 6-a-side games with SG resulting in increased total running performance. In conclusion, the current observations reveal that 4-a-side NP, SG, and RG have the highest physiological demands with 4-a-side SG having increased running performance in contrast to other game design and goal-type games. Furthermore, independent of game design and goal type, 4-a-side SSG show increased relative intensity compared with 5-a-side and 6-a-side SSG.
Water resources of southeastern Oahu, Hawaii
Takasaki, K.J.; Mink, John F.
1982-01-01
Southeastern Oahu comprises the eastern end of the Koolau Range and is divided into two roughly equal parts by the crest of the range. The northside of the crest is commonly called the windward side and the southside, the leeward. Precipitous cliffs aproned by a gently sloping landscape are the main topographic features on the windward side. The leeward side is a gentle lava-flow slope incised by steep narrow valleys. The main Koolau fissure zone, including the caldera, lies on the windward side. The leeward side includes minor rift zones that are perpendicular to and intersect the main fissure zone. Dikes in the main fissure zone strike from nearly east-west in the eastern end to about N. 55? W. in the western part. Dikes in the minor rift zones strike from north-south to slightly northeasterly. Water use is about 18 Mgal/d (million gallons per day) of which only 4 Mgal/d is obtained locally from ground-water sources. About a third of the 14 Mgal/d deficit is imported from sources northwest of the study area on the windward side and the remainder from sources in the Honolulu and Pearl Harbor areas on the leeward side. The 4 Mgal/d being developed represents only about 3 percent of the area's rainfall compared to a development-rainfall ratio of 20 percent for the rest of the island. Streams are short and flashy. Perennial streamflow to the sea occurs only in Maunawili Valley and in the Waimanalo area. Mean annual discharge is estimated at 20 Mgal/d in the windward side and at 15 Mgal/d on the leeward side. Low flow, expressed as the flow that is equaled or exceeded 90 percent of the time, is 5 Mgal/d windward of the crest and zero leeward of it. Most fresh ground water occurs in lava flows of the Koolau Volcanics. It is impounded by dikes in the rift zones and floats on saline ground water as lenses outside the rift zones. Small but important bodies of freshwater are perched in volcanic rocks of the Honolulu Group in Maunawili Valley. Fresh ground water occurs in near-shore calcareous sands that overlie a clay horizon in the Waimanalo area. Deeply buried talus and alluvium also carry fresh ground water in the Waimanalo area. Wells tapping saline ground water in fresh lava flows of the Honolulu Group provide water for a sea-life park in the Makapuu area. The same aquifer is tapped by wells for disposal of the saline waste water. The current development scheme in the windward side that utilizes only the free-flow equilibrium discharge of dike-impounded water is inefficient and does not cope with the annual weather cycle. The flow available for development under this scheme is greatest in the rainy winter months when demand is the lowest and least in the summer months when demand is the highest. A more optimal scheme would be to change this natural flow pattern by depleting storage by pumping to increase flow in the high-demand summer months and allowing the depleted storage to recover naturally in the low-demand winter months. Depleting storage would lower water levels which would provide more room for infiltration and provide less opportunity for evapotranspiration. The basal-water reservoir in the leeward side is isolated hydrologically from abutting reservoirs outside the area and can and should be fully exploited. The existing development of the basal-water reservoir is small compared to the natural ground-water flow and that part not being developed is wasting to the sea. Because the area is hydrologically isolated, development will not be detrimental to or reduce the ground-water supply outside the area.
ERIC Educational Resources Information Center
Patrinos, Harry Anthony; Ariasingam, David Lakshmanan
Central governments' supply-side expansions of schooling have not equally benefited all members of society, especially girls, indigenous peoples, tribal groups, disadvantaged minorities, and the poor. Public spending on education is often inefficient, higher education is subsidized at primary education's expense, and costs are becoming…
Accurate Estimation of Target amounts Using Expanded BASS Model for Demand-Side Management
NASA Astrophysics Data System (ADS)
Kim, Hyun-Woong; Park, Jong-Jin; Kim, Jin-O.
2008-10-01
The electricity demand in Korea has rapidly increased along with a steady economic growth since 1970s. Therefore Korea has positively propelled not only SSM (Supply-Side Management) but also DSM (Demand-Side Management) activities to reduce investment cost of generating units and to save supply costs of electricity through the enhancement of whole national energy utilization efficiency. However study for rebate, which have influence on success or failure on DSM program, is not sufficient. This paper executed to modeling mathematically expanded Bass model considering rebates, which have influence on penetration amounts for DSM program. To reflect rebate effect more preciously, the pricing function using in expanded Bass model directly reflects response of potential participants for rebate level.
Analytical sizing methods for behind-the-meter battery storage
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Di; Kintner-Meyer, Michael; Yang, Tao
In behind-the-meter application, battery storage system (BSS) is utilized to reduce a commercial or industrial customer’s payment for electricity use, including energy charge and demand charge. The potential value of BSS in payment reduction and the most economic size can be determined by formulating and solving standard mathematical programming problems. In this method, users input system information such as load profiles, energy/demand charge rates, and battery characteristics to construct a standard programming problem that typically involve a large number of constraints and decision variables. Such a large scale programming problem is then solved by optimization solvers to obtain numerical solutions.more » Such a method cannot directly link the obtained optimal battery sizes to input parameters and requires case-by-case analysis. In this paper, we present an objective quantitative analysis of costs and benefits of customer-side energy storage, and thereby identify key factors that affect battery sizing. Based on the analysis, we then develop simple but effective guidelines that can be used to determine the most cost-effective battery size or guide utility rate design for stimulating energy storage development. The proposed analytical sizing methods are innovative, and offer engineering insights on how the optimal battery size varies with system characteristics. We illustrate the proposed methods using practical building load profile and utility rate. The obtained results are compared with the ones using mathematical programming based methods for validation.« less
NASA Astrophysics Data System (ADS)
Tańczuk, Mariusz; Radziewicz, Wojciech; Olszewski, Eligiusz; Skorek, Janusz
2017-10-01
District heating technologies should be efficient, effective and environmentally friendly. The majority of the communal heating systems in Poland produce district hot water in coal-fired boilers. A large number of them are considerably worn out, low-efficient in the summer time and will not comply with forthcoming regulations. One of the possible solution for such plants is repowering with new CHP systems or new boilers fuelled with fuels alternative to coal. Optimisation analysis of the target configuration of municipal heat generating plant is analysed in the paper. The work concerns repowering the existing conventional heat generating plant according to eight different scenarios of the plant configuration meeting technical and environmental requirements forecasted for the year of 2035. The maximum demand for heat of the system supplied by the plant is 185 MW. Taking into account different technical configurations on one side, and different energy and fuel prices on the other side, the comparative cost-benefits analysis of the assumed scenarios has been made. The basic economical index NPV (net present value) has been derived for each analysed scenario and the results have been compared and discussed. It was also claimed that the scenario with CHP based on ICE engines is optimal.
The macroeconomics of demographic unemployment.
Carlberg, M
1990-02-01
"What are the macroeconomic consequences of an increase in labour supply? In the short run, unemployment occurs, due to both lack of aggregate demand and capital shortage. Demand-side policy and money wage restraint prove to be ineffective in this situation, owing to capital shortage. On the other hand, a reduction in working hours without wage compensation as well as a policy mix of both demand-side policy and investment policy turn out to be effective. The reduction in working hours lowers individual income and raises individual leisure, as compared to the policy mix." (SUMMARY IN GER) excerpt
ERIC Educational Resources Information Center
West, Anne; Sparkes, Jo; Balabanov, Todor
The use of demand-side financing mechanisms and vouchers for postcompulsory secondary-level education was examined through case studies of funding practices in the following countries: Austria; France; the United Kingdom; the United States; and Wallonia (the French community of Belgium). Different models of voucher use were identified in the…
Creating a High-Skills Society during Recession: Issues for Policy Makers
ERIC Educational Resources Information Center
Panagiotakopoulos, Antonios
2015-01-01
The present study looks at the skill formation policies adopted by policy makers in Greece in order to create a high-skills society. It examines empirically the demand side of the skill creation process within 300 small enterprises in order to understand how far supply-side measures have influenced the demand for well-trained staff within small…
ERIC Educational Resources Information Center
Sineta, Abraham
2012-01-01
Despite the push for universal education, many disadvantaged and poor children in developing countries still do not have access to basic education. This among other reasons is due to poverty where poor families cannot afford the cost of basic education even when it is "free" of tuition (McDonald, 2007). Demand-side financing…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schweitzer, M.
1991-01-01
Integrated resource planning differs from traditional utility planning practices primarily in its increased attention to demand-side management (DSM) programs and its integration of supply- and demand-side resources into a combined resource portfolio. This report details the findings from an Oak Ridge National Laboratory (ORNL) survey of 24 electric utilities that have well-developed integrated planning processes. These utilities account for roughly one-third of total capacity, electricity generation, and DSM-program expenditures nationwide. The ORNL survey was designed to obtain descriptive data on a national sample of utilities and to test a number of hypothesized relationships between selected utility characteristics and the mixmore » of resources selected for the integrated plan, with an emphasis on the use of DSM resources and the processes by which they are chosen. The survey solicited information on each utility's current and projected resource mix, operating environment, procedures used to screen potential DSM resources, techniques used to obtain public input and to integrate supply- and demand-side options into a unified plan, and procedures used in the final selection of resources for the plan.« less
NASA Astrophysics Data System (ADS)
Becerra Lopez, Humberto Ruben
2007-12-01
High expansion of power demand is expected in the Upper Rio Grande region (El Paso, Hudspeth, Culberson, Jeff Davis, Presidio and Brewster counties) as a result of both electrical demand growth and decommissioning of installed capacity. On the supply side a notable deployment of renewable power technologies can be projected owing to the recent introduction of a new energy policy in Texas, which attempts to reach 10,000 installed-MWe of renewable capacity for 2025. Power generation fueled by natural-gas might consistently expand due to the encouraged use of this fuel. In this context the array of participating technologies can be optimized, which, within a sustainability framework, translates into a multidimensional problem. The solution to the problem is presented through this dissertation in two main parts. The first part solves the thermodynamic-environmental problem through developing a dynamic model to project maximum allowable expansion of technologies. Predetermined alternatives include diverse renewable energy technologies (wind turbine, photovoltaic conversion, hybrid solar thermal parabolic trough, and solid oxide fuel cells), a conventional fossil-fuel technology (natural gas combined-cycle), and a breakthrough fossil-fuel technology (solid oxide fuel cells). The analysis is based on the concept of cumulative exergy consumption, expanded to include abatement of emissions. A Gompertz sigmoid growth is assumed and constrained by both exergetic self-sustenance and regional energy resource availability. This part of the analysis assumes that power demand expansion is met by full deployment of alternative technologies backed up by conventional technology. Results show that through a proper allowance for exergy reinvestment the power demand expansion may be met largely by alternative technologies minimizing the primary resource depletion. The second part of the study makes use of the dynamic model to support a multi-objective optimization routine, where the exergetic and economic costs are established as primary competing factors. An optimization algorithm is implemented using the constraint method. The solution is given as Pareto optimality with arrays for minimum cost and possible arrays for the tradeoff front. These arrays are further analyzed in terms of sustainability, cumulative exergy loss (i.e. irreversibilities and waste exergy) and incremental economic cost, and the results are compared with the goals of current legislated energy policy.
Raju, Leo; Milton, R S; Mahadevan, Senthilkumaran
The objective of this paper is implementation of multiagent system (MAS) for the advanced distributed energy management and demand side management of a solar microgrid. Initially, Java agent development environment (JADE) frame work is used to implement MAS based dynamic energy management of solar microgrid. Due to unstable nature of MATLAB, when dealing with multithreading environment, MAS operating in JADE is linked with the MATLAB using a middle ware called Multiagent Control Using Simulink with Jade Extension (MACSimJX). MACSimJX allows the solar microgrid components designed with MATLAB to be controlled by the corresponding agents of MAS. The microgrid environment variables are captured through sensors and given to agents through MATLAB/Simulink and after the agent operations in JADE, the results are given to the actuators through MATLAB for the implementation of dynamic operation in solar microgrid. MAS operating in JADE maximizes operational efficiency of solar microgrid by decentralized approach and increase in runtime efficiency due to JADE. Autonomous demand side management is implemented for optimizing the power exchange between main grid and microgrid with intermittent nature of solar power, randomness of load, and variation of noncritical load and grid price. These dynamics are considered for every time step and complex environment simulation is designed to emulate the distributed microgrid operations and evaluate the impact of agent operations.
Taxes on tobacco, alcohol and sugar sweetened beverages: Linkages and lessons learned.
Blecher, Evan
2015-07-01
Increased consumption of sugar-sweetened beverages (SSBs) has been linked to increases in obesity in both high-income and low- and middle-income countries. Tobacco and alcohol taxes have proven to be effective tools to reduce tobacco and alcohol use. Many public health advocates propose using similar taxes to reduce consumption of SSBs. South Africa is a middle-income country that is considered a leader in the area of tobacco tax policy. A case study of tobacco and alcohol taxes is used to better understand optimal tax structures for SSBs. The case study tracks aggregate data over time on taxes, prices, consumption, tax revenues, and marketing expenditures at the brand level. Tobacco and alcohol taxes are shown to be effective in reducing the demand for tobacco. Additionally, taxes on the dose of alcohol rather than the volume of the beverage may incentivize producers to reduce the volume of alcohol in beverages through the supply side. While specific taxes based on the volume of beverages are likely to reduce the demand for SSBs, policy makers should also consider taxes on alcohol and SSBs that tax the dose of the alcohol and calories in order to create supply-side incentives for producers to lower alcohol and calorie levels in existing products or promote products with lower levels of alcohol and calories. Copyright © 2015 Elsevier Ltd. All rights reserved.
Raju, Leo; Milton, R. S.; Mahadevan, Senthilkumaran
2016-01-01
The objective of this paper is implementation of multiagent system (MAS) for the advanced distributed energy management and demand side management of a solar microgrid. Initially, Java agent development environment (JADE) frame work is used to implement MAS based dynamic energy management of solar microgrid. Due to unstable nature of MATLAB, when dealing with multithreading environment, MAS operating in JADE is linked with the MATLAB using a middle ware called Multiagent Control Using Simulink with Jade Extension (MACSimJX). MACSimJX allows the solar microgrid components designed with MATLAB to be controlled by the corresponding agents of MAS. The microgrid environment variables are captured through sensors and given to agents through MATLAB/Simulink and after the agent operations in JADE, the results are given to the actuators through MATLAB for the implementation of dynamic operation in solar microgrid. MAS operating in JADE maximizes operational efficiency of solar microgrid by decentralized approach and increase in runtime efficiency due to JADE. Autonomous demand side management is implemented for optimizing the power exchange between main grid and microgrid with intermittent nature of solar power, randomness of load, and variation of noncritical load and grid price. These dynamics are considered for every time step and complex environment simulation is designed to emulate the distributed microgrid operations and evaluate the impact of agent operations. PMID:27127802
Utility Sector Impacts of Reduced Electricity Demand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coughlin, Katie
2014-12-01
This report presents a new approach to estimating the marginal utility sector impacts associated with electricity demand reductions. The method uses publicly available data and provides results in the form of time series of impact factors. The input data are taken from the Energy Information Agency's Annual Energy Outlook (AEO) projections of how the electric system might evolve in the reference case, and in a number of side cases that incorporate different effciency and other policy assumptions. The data published with the AEO are used to define quantitative relationships between demand-side electricity reductions by end use and supply-side changes tomore » capacity by plant type, generation by fuel type and emissions of CO2, Hg, NOx and SO2. The impact factors define the change in each of these quantities per unit reduction in site electricity demand. We find that the relative variation in these impacts by end use is small, but the time variation can be significant.« less
Advanced microgrid design and analysis for forward operating bases
NASA Astrophysics Data System (ADS)
Reasoner, Jonathan
This thesis takes a holistic approach in creating an improved electric power generation system for a forward operating base (FOB) in the future through the design of an isolated microgrid. After an extensive literature search, this thesis found a need for drastic improvement of the FOB power system. A thorough design process analyzed FOB demand, researched demand side management improvements, evaluated various generation sources and energy storage options, and performed a HOMERRTM discrete optimization to determine the best microgrid design. Further sensitivity analysis was performed to see how changing parameters would affect the outcome. Lastly, this research also looks at some of the challenges which are associated with incorporating a design which relies heavily on inverter-based generation sources, and gives possible solutions to help make a renewable energy powered microgrid a reality. While this thesis uses a FOB as the case study, the process and discussion can be adapted to aide in the design of an off-grid small-scale power grid which utilizes high-penetration levels of renewable energy.
2014-01-01
Background Performance measures are often neglected during the transition period of national health insurance scheme implementation in many low and middle income countries. These measurements evaluate the extent to which various aspects of the schemes meet their key objectives. This study assesses the implementation of a health insurance scheme using optimal resource use domains and examines possible factors that influence each domain, according to providers’ perspectives. Methods A retrospective, cross-sectional survey was done between August and December 2010 in Kaduna state, and 466 health care provider personnel were interviewed. Optimal-resource-use was defined in four domains: provider payment mechanism (capitation and fee-for-service payment methods), benefit package, administrative efficiency, and active monitoring mechanism. Logistic regression analysis was used to identify provider factors that may influence each domain. Results In the provider payment mechanism domain, capitation payment method (95%) performed better than fee-for-service payment method (62%). Benefit package domain performed strongly (97%), while active monitoring mechanism performed weakly (37%). In the administrative efficiency domain, both promptness of referral system (80%) and prompt arrival of funds (93%) performed well. At the individual level, providers with fewer enrolees encountered difficulties with reimbursement. Other factors significantly influenced each of the optimal-resource-use domains. Conclusions Fee-for-service payment method and claims review, in the provider payment and active monitoring mechanisms, respectively, performed weakly according to the providers’ (at individual-level) perspectives. A short-fall on the supply-side of health insurance could lead to a direct or indirect adverse effect on the demand-side of the scheme. Capitation payment per enrolees should be revised to conform to economic circumstances. Performance indicators and providers’ characteristics and experiences associated with resource use can assist policy makers to monitor and evaluate health insurance implementation. PMID:24628889
Optimizing the thermophilic hydrolysis of grass silage in a two-phase anaerobic digestion system.
Orozco, A M; Nizami, A S; Murphy, J D; Groom, E
2013-09-01
Thermophilic hydrolysis of grass silage (GS) at 55 °C with organic loading rates (OLRs) of 6.5, 5, 2.5 and 1.0 kg VS m(-3) days(-1) and hydraulic retention times (HRT) of 10, 6, 4 and 2 days were evaluated in 12 glass bioreactors side by side. The hydrolytic process was measured by variation in pH, volatile solids (VS), VS destruction, soluble chemical oxygen demand (sCOD), hydrolysis and acidification yields. Biological methane potential (BMP) assays were carried out to measure the upper limit for methane production of grass silage with different hydrolytic pretreatments at mesophilic temperature (37 °C). The optimum methane yield of 368 LN CH4 kg(-1) VS was obtained at an OLR of 1 kg VS m(-3)days(-1) and a HRT of 4 days, showing an increase of 30% in the methane potential in comparison to non-hydrolysed GS. Copyright © 2013 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Bjarnason, Thoroddur; Steriu, Andreea; Kokkevi, Anna
2010-01-01
Aims: Most national drug policies target both the supply side and the demand side of illicit drug use. Although such policies are intended to affect individual choices, they by definition operate on a national level and cannot be evaluated solely on the basis of individual-level differences. This study aims to evaluate the impact of country-level…
The Black-White Difference in Youth Employment: Evidence for Demand-Side Factors.
ERIC Educational Resources Information Center
Cain, Glen G.; Finnie, Ross
The 1980 Census of the United States is used, first, to illustrate the serious lag in employment performance of young black men relative to young white men and, second, to test for the importance of demand-side causes of this lag. Aggregate data for 94 standard metropolitan statistical areas (SMSAs) contain data on the annual hours worked in 1979…
Generalized networking engineering: optimal pricing and routing in multiservice networks
NASA Astrophysics Data System (ADS)
Mitra, Debasis; Wang, Qiong
2002-07-01
One of the functions of network engineering is to allocate resources optimally to forecasted demand. We generalize the mechanism by incorporating price-demand relationships into the problem formulation, and optimizing pricing and routing jointly to maximize total revenue. We consider a network, with fixed topology and link bandwidths, that offers multiple services, such as voice and data, each having characteristic price elasticity of demand, and quality of service and policy requirements on routing. Prices, which depend on service type and origin-destination, determine demands, that are routed, subject to their constraints, so as to maximize revenue. We study the basic properties of the optimal solution and prove that link shadow costs provide the basis for both optimal prices and optimal routing policies. We investigate the impact of input parameters, such as link capacities and price elasticities, on prices, demand growth, and routing policies. Asymptotic analyses, in which network bandwidth is scaled to grow, give results that are noteworthy for their qualitative insights. Several numerical examples illustrate the analyses.
NASA Astrophysics Data System (ADS)
Huo, Xianxu; Li, Guodong; Jiang, Ling; Wang, Xudong
2017-08-01
With the development of electricity market, distributed generation (DG) technology and related policies, regional energy suppliers are encouraged to build DG. Under this background, the concept of active distribution network (ADN) is put forward. In this paper, a bi-level model of intermittent DG considering benefit of regional energy suppliers is proposed. The objective of the upper level is the maximization of benefit of regional energy suppliers. On this basis, the lower level is optimized for each scene. The uncertainties of DG output and load of users, as well as four active management measures, which include demand-side management, curtailing the output power of DG, regulating reactive power compensation capacity and regulating the on-load tap changer, are considered. Harmony search algorithm and particle swarm optimization are combined as a hybrid strategy to solve the model. This model and strategy are tested with IEEE-33 node system, and results of case study indicate that the model and strategy successfully increase the capacity of DG and benefit of regional energy suppliers.
Optimal Scheduling Method of Controllable Loads in DC Smart Apartment Building
NASA Astrophysics Data System (ADS)
Shimoji, Tsubasa; Tahara, Hayato; Matayoshi, Hidehito; Yona, Atsushi; Senjyu, Tomonobu
2015-12-01
From the perspective of global warming suppression and the depletion of energy resources, renewable energies, such as the solar collector (SC) and photovoltaic generation (PV), have been gaining attention in worldwide. Houses or buildings with PV and heat pumps (HPs) are recently being used in residential areas widely due to the time of use (TOU) electricity pricing scheme which is essentially inexpensive during middle-night and expensive during day-time. If fixed batteries and electric vehicles (EVs) can be introduced in the premises, the electricity cost would be even more reduced. While, if the occupants arbitrarily use these controllable loads respectively, power demand in residential buildings may fluctuate in the future. Thus, an optimal operation of controllable loads such as HPs, batteries and EV should be scheduled in the buildings in order to prevent power flow from fluctuating rapidly. This paper proposes an optimal scheduling method of controllable loads, and the purpose is not only the minimization of electricity cost for the consumers, but also suppression of fluctuation of power flow on the power supply side. Furthermore, a novel electricity pricing scheme is also suggested in this paper.
Exploring How Technology Growth Limits Impact Optimal Carbon dioxide Mitigation Pathways
Energy system optimization models prescribe the optimal mix of technologies and fuels for meeting energy demands over a time horizon, subject to energy supplies, demands, and other constraints. When optimizing, these models will, to the extent allowed, favor the least cost combin...
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.
Universities Response to Oil and Gas Industry Demands in South Texas (USA) and Tamaulipas (Mexico)
ERIC Educational Resources Information Center
Navarro, Marco Aurelio
2016-01-01
Given the importance of hydrocarbons for this area, the purpose of this paper is to explore the response of universities to cope with new demands in the south of Texas and Tamaulipas, especially in relation to gas plays of Eagle Ford (Texas side) and Burgos Basin (Mexican side). To accomplish this task, in the first section of the paper a broad…
NASA Astrophysics Data System (ADS)
Furusawa, Ken; Sugihara, Hideharu; Tsuji, Kiichiro
Opened wholesale electric power market in April 2005, deregulation of electric power industry in Japan has faced a new competitive environment. In the new environment, Independent Power Producer (: IPP), Power Producer and Supplier (: PPS), Load Service Entity (: LSE) and electric utility can trade electric energy through both bilateral contracts and single-price auction at the electricity market. In general, the market clearing price (: MCP) is largely changed by amount of total load demand in the market. The influence may cause price spike, and consequently the volatility of MCP will make LSEs and their customers to face a risk of revenue and cost. DSM is attracted as a means of load leveling, and has effect on decreasing MCP at peak load period. Introducing Energy Storage systems (: ES) is one of DSM in order to change demand profile at customer-side. In case that customers decrease their own demand at jumped MCP, a bidding strategy of generating companies may be changed their strategy. As a result, MCP is changed through such complex mechanism. In this paper the authors evaluate MCP by multi-agent. It is considered that customer-side ES has an effect on MCP fluctuation. Through numerical examples, this paper evaluates the influence on MCP by controlling customer-side ES corresponding to variation of MCP.
Game Demands of Seven-A-Side Soccer in Young Players.
Barbero-Alvarez, José C; Gómez-López, Maite; Castagna, Carlo; Barbero-Alvarez, Verónica; Romero, David V; Blanchfield, Anthony W; Nakamura, Fábio Y
2017-07-01
Barbero-Alvarez, JC, Gómez-López, M, Castagna, C, Barbero-Alvarez, V, Romero, DV, Blanchfield, AW, and Nakamura, FY. Game demands of seven-a-side soccer in young players. J Strength Cond Res 31(7): 1771-1779, 2017-The aim of this study was to examine the activity patterns and physiological demands of 7-a-side youth soccer matches across 2 chronological age categories (U12 and U14). Twenty-two soccer players of a national youth soccer academy were investigated. Players of each age category performed 2 training matches (2 × 25 minutes) and were monitored by global positioning system and heart rate monitor units. Players of both categories covered similar total distance (5,348 ± 307 m), at similar mean heart rate values (86 ± 4% of maximum). However, the number of high-intensity runs (82.5 ± 17.4 vs. 69.7 ± 15.2) and total distance covered during sprints (264 ± 207 vs. 128 ± 74 m) were significantly (p ≤ 0.05) higher in U14 compared with U12. The results suggest a highly demanding nature of 7-a-side soccer for skilled players, with physical maturity possibly influencing the match-related high-intensity performance at these ages.
Bulk electric system reliability evaluation incorporating wind power and demand side management
NASA Astrophysics Data System (ADS)
Huang, Dange
Electric power systems are experiencing dramatic changes with respect to structure, operation and regulation and are facing increasing pressure due to environmental and societal constraints. Bulk electric system reliability is an important consideration in power system planning, design and operation particularly in the new competitive environment. A wide range of methods have been developed to perform bulk electric system reliability evaluation. Theoretically, sequential Monte Carlo simulation can include all aspects and contingencies in a power system and can be used to produce an informative set of reliability indices. It has become a practical and viable tool for large system reliability assessment technique due to the development of computing power and is used in the studies described in this thesis. The well-being approach used in this research provides the opportunity to integrate an accepted deterministic criterion into a probabilistic framework. This research work includes the investigation of important factors that impact bulk electric system adequacy evaluation and security constrained adequacy assessment using the well-being analysis framework. Load forecast uncertainty is an important consideration in an electrical power system. This research includes load forecast uncertainty considerations in bulk electric system reliability assessment and the effects on system, load point and well-being indices and reliability index probability distributions are examined. There has been increasing worldwide interest in the utilization of wind power as a renewable energy source over the last two decades due to enhanced public awareness of the environment. Increasing penetration of wind power has significant impacts on power system reliability, and security analyses become more uncertain due to the unpredictable nature of wind power. The effects of wind power additions in generating and bulk electric system reliability assessment considering site wind speed correlations and the interactive effects of wind power and load forecast uncertainty on system reliability are examined. The concept of the security cost associated with operating in the marginal state in the well-being framework is incorporated in the economic analyses associated with system expansion planning including wind power and load forecast uncertainty. Overall reliability cost/worth analyses including security cost concepts are applied to select an optimal wind power injection strategy in a bulk electric system. The effects of the various demand side management measures on system reliability are illustrated using the system, load point, and well-being indices, and the reliability index probability distributions. The reliability effects of demand side management procedures in a bulk electric system including wind power and load forecast uncertainty considerations are also investigated. The system reliability effects due to specific demand side management programs are quantified and examined in terms of their reliability benefits.
(NH4)2SO4 recovery from liquid side streams.
Boehler, Marc Anton; Heisele, Alexander; Seyfried, Alexander; Grömping, Markus; Siegrist, Hansruedi
2015-05-01
Two methods of recovering nitrogen from liquid side streams are presented in this paper. The first method was demonstrated at an ammonia stripping plant treating 5-7 m(3)/h sludge water at the wastewater treatment plant (WWTP) Kloten-Opfikon (CH). In addition to the usual stripping and scrubbing columns, a third column had been added in order strip CO₂, thus reducing the NaOH-demand of the subsequent ammonia stripping. At first, just the stripping plant was put into operation and optimized without any pre-treatment of the supernatant. Next, the CO₂-stripper column was activated and optimized by gas measurements to minimize free ammonia losses, heat losses, and energy consumption. Key operational aspects of the plant were evaluated. Finally, up to 1.4 m(3)/h source-separated urine was successfully fed into the stripping facility. The second ammonia removal method using hydrophobic hollow fiber membranes was tested in two small pilot systems by different manufacturers in 2012 and 2013 at WWTP Neugut. In this technology, free ammonia gas in the sludge liquid diffuses at pH >9.3 from the sludge liquid through the air-filled pores of the microporous hydrophobic membrane into concentrated sulfuric acid flowing through the hollow fibers, forming ammonium sulfate. The small pore size and the hydrophobic nature of the membrane prevent the liquid phase from entering into the pores due to the surface tension effect. Practical experience regarding operational parameters like wastewater flow rate, pH, temperature, ammonia concentration, fouling and precipitations processes, optimal flow schemes, and process configurations was collected.
Demand side management in recycling and electricity retail pricing
NASA Astrophysics Data System (ADS)
Kazan, Osman
This dissertation addresses several problems from the recycling industry and electricity retail market. The first paper addresses a real-life scheduling problem faced by a national industrial recycling company. Based on their practices, a scheduling problem is defined, modeled, analyzed, and a solution is approximated efficiently. The recommended application is tested on the real-life data and randomly generated data. The scheduling improvements and the financial benefits are presented. The second problem is from electricity retail market. There are well-known patterns in daily usage in hours. These patterns change in shape and magnitude by seasons and days of the week. Generation costs are multiple times higher during the peak hours of the day. Yet most consumers purchase electricity at flat rates. This work explores analytic pricing tools to reduce peak load electricity demand for retailers. For that purpose, a nonlinear model that determines optimal hourly prices is established based on two major components: unit generation costs and consumers' utility. Both are analyzed and estimated empirically in the third paper. A pricing model is introduced to maximize the electric retailer's profit. As a result, a closed-form expression for the optimal price vector is obtained. Possible scenarios are evaluated for consumers' utility distribution. For the general case, we provide a numerical solution methodology to obtain the optimal pricing scheme. The models recommended are tested under various scenarios that consider consumer segmentation and multiple pricing policies. The recommended model reduces the peak load significantly in most cases. Several utility companies offer hourly pricing to their customers. They determine prices using historical data of unit electricity cost over time. In this dissertation we develop a nonlinear model that determines optimal hourly prices with parameter estimation. The last paper includes a regression analysis of the unit generation cost function obtained from Independent Service Operators. A consumer experiment is established to replicate the peak load behavior. As a result, consumers' utility function is estimated and optimal retail electricity prices are computed.
CO{sub 2} mitigation potential of efficient demand-side technologies: The case of Thailand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shrestha, R.M.; Biswas, W.K.; Timilsina, G.R.
This study assesses the techno-economic potential of selected demand-side efficient appliances to mitigate CO{sub 2} emission from the power sector in Thailand under national, consumer, and utility perspectives. A key finding of this study is that about 5.5--7% of the total annual CO{sub 2} emission from the electricity sector of the country can be reduced during 1996--2011 from the national perspective.
Supply and demand: negotiating the prescription drug labyrinth to reduce costs.
DeStefino, Kevin
2003-01-01
Prescription drug costs are increasing at a rate of 15% to 17% a year and a look into the future does not bring much better news. Employers can expect to see more numbers like these as doctors more aggressively treat diseases using drug therapy, the population continues to age and pharmaceutical companies continue to spend billions of dollars on direct-to-consumer advertising aimed at consumers who are desensitized to the true costs of their prescriptions. In this environment, it is unlikely that companies can realistically expect to reverse costs of even to avoid cost increases. However, this article provides employers with a prudent approach to managing both the supply and demand sides of the prescription drug equation in order to reduce their level of increase. Supply-side management focuses on negotiations with vendors, while the demand side focuses on managing employee utilization.
Urban development control based on transportation carrying capacity
NASA Astrophysics Data System (ADS)
Miharja, M.; Sjafruddin, A. H.
2017-06-01
Severe transportation problems in Indonesian urban areas are stimulated by one fundamental factor, namely lack of awareness on transportation carrying capacity in these areas development control. Urban land use development towards more physical coverage is typically not related with the capability of transportation system to accommodate additional trips volume. Lack of clear connection between development permit with its implication on the transportation side has led to a phenomenon of exceeding transport demand over supply capacity. This paper discusses the concept of urban land use development control which will be related with transport carrying capacity. The discussion would cover both supply and demand sides of transportation. From supply side, the analysis regarding the capacity of transport system would take both existing as well as potential road network capacity could be developed. From demand side, the analysis would be through the control of a maximum floor area and public transport provision. Allowed maximum floor area for development would be at the level of generating traffic at reasonable volume. Ultimately, the objective of this paper is to introduce model to incorporate transport carrying capacity in Indonesian urban land use development control.
Engineering two-wire optical antennas for near field enhancement
NASA Astrophysics Data System (ADS)
Yang, Zhong-Jian; Zhao, Qian; Xiao, Si; He, Jun
2017-07-01
We study the optimization of near field enhancement in the two-wire optical antenna system. By varying the nanowire sizes we obtain the optimized side-length (width and height) for the maximum field enhancement with a given gap size. The optimized side-length applies to a broadband range (λ = 650-1000 nm). The ratio of extinction cross section to field concentration size is found to be closely related to the field enhancement behavior. We also investigate two experimentally feasible cases which are antennas on glass substrate and mirror, and find that the optimized side-length also applies to these systems. It is also found that the optimized side-length shows a tendency of increasing with the gap size. Our results could find applications in field-enhanced spectroscopies.
Developing Server-Side Infrastructure for Large-Scale E-Learning of Web Technology
ERIC Educational Resources Information Center
Simpkins, Neil
2010-01-01
The growth of E-business has made experience in server-side technology an increasingly important area for educators. Server-side skills are in increasing demand and recognised to be of relatively greater value than comparable client-side aspects (Ehie, 2002). In response to this, many educational organisations have developed E-business courses,…
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.
Cui, Borui; Gao, Dian-ce; Xiao, Fu; ...
2016-12-23
This article provides a method in comprehensive evaluation of cost-saving potential of active cool thermal energy storage (CTES) integrated with HVAC system for demand management in non-residential building. The active storage is beneficial by shifting peak demand for peak load management (PLM) as well as providing longer duration and larger capacity of demand response (DR). In this research, a model-based optimal design method using genetic algorithm is developed to optimize the capacity of active CTES aiming for maximizing the life-cycle cost saving concerning capital cost associated with storage capacity as well as incentives from both fast DR and PLM. Inmore » the method, the active CTES operates under a fast DR control strategy during DR events while under the storage-priority operation mode to shift peak demand during normal days. The optimal storage capacities, maximum annual net cost saving and corresponding power reduction set-points during DR event are obtained by using the proposed optimal design method. Lastly, this research provides guidance in comprehensive evaluation of cost-saving potential of CTES integrated with HVAC system for building demand management including both fast DR and PLM.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cui, Borui; Gao, Dian-ce; Xiao, Fu
This article provides a method in comprehensive evaluation of cost-saving potential of active cool thermal energy storage (CTES) integrated with HVAC system for demand management in non-residential building. The active storage is beneficial by shifting peak demand for peak load management (PLM) as well as providing longer duration and larger capacity of demand response (DR). In this research, a model-based optimal design method using genetic algorithm is developed to optimize the capacity of active CTES aiming for maximizing the life-cycle cost saving concerning capital cost associated with storage capacity as well as incentives from both fast DR and PLM. Inmore » the method, the active CTES operates under a fast DR control strategy during DR events while under the storage-priority operation mode to shift peak demand during normal days. The optimal storage capacities, maximum annual net cost saving and corresponding power reduction set-points during DR event are obtained by using the proposed optimal design method. Lastly, this research provides guidance in comprehensive evaluation of cost-saving potential of CTES integrated with HVAC system for building demand management including both fast DR and PLM.« less
Virtual atmospheric mercury emission network in China.
Liang, Sai; Zhang, Chao; Wang, Yafei; Xu, Ming; Liu, Weidong
2014-01-01
Top-down analysis of virtual atmospheric mercury emission networks can direct efficient demand-side policy making on mercury reductions. Taking China-the world's top atmospheric mercury emitter-as a case, we identify key contributors to China's atmospheric mercury emissions from both the producer and the consumer perspectives. China totally discharged 794.9 tonnes of atmospheric mercury emissions in 2007. China's production-side control policies should mainly focus on key direct mercury emitters such as Liaoning, Hebei, Shandong, Shanxi, Henan, Hunan, Guizhou, Yunnan, and Inner Mongolia provinces and sectors producing metals, nonmetallic mineral products, and electricity and heat power, while demand-side policies should mainly focus on key underlying drivers of mercury emissions such as Shandong, Jiangsu, Zhejiang, and Guangdong provinces and sectors of construction activities and equipment manufacturing. China's interregional embodied atmospheric mercury flows are generally moving from the inland to the east coast. Beijing-Tianjin (with 4.8 tonnes of net mercury inflows) and South Coast (with 3.3 tonnes of net mercury inflows) are two largest net-inflow regions, while North (with 5.3 tonnes of net mercury outflows) is the largest net-outflow region. We also identify primary supply chains contributing to China's virtual atmospheric mercury emission network, which can be used to trace the transfers of production-side and demand-side policy effects.
On-demand server-side image processing for web-based DICOM image display
NASA Astrophysics Data System (ADS)
Sakusabe, Takaya; Kimura, Michio; Onogi, Yuzo
2000-04-01
Low cost image delivery is needed in modern networked hospitals. If a hospital has hundreds of clients, cost of client systems is a big problem. Naturally, a Web-based system is the most effective solution. But a Web browser could not display medical images with certain image processing such as a lookup table transformation. We developed a Web-based medical image display system using Web browser and on-demand server-side image processing. All images displayed on a Web page are generated from DICOM files on a server, delivered on-demand. User interaction on the Web page is handled by a client-side scripting technology such as JavaScript. This combination makes a look-and-feel of an imaging workstation not only for its functionality but also for its speed. Real time update of images with tracing mouse motion is achieved on Web browser without any client-side image processing which may be done by client-side plug-in technology such as Java Applets or ActiveX. We tested performance of the system in three cases. Single client, small number of clients in a fast speed network, and large number of clients in a normal speed network. The result shows that there are very slight overhead for communication and very scalable in number of clients.
Ahmed, Shakil; Khan, M Mahmud
2011-01-01
It is now more than 2 years since the Ministry of Health and Family Welfare of the Government of Bangladesh implemented the Maternal Health Voucher Scheme, a specialized form of demand-side financing programme. To analyse the early lessons from the scheme, information was obtained through semi-structured interviews with stakeholders at the sub-district level. The analysis identified a number of factors affecting the efficiency and performance of the scheme in the program area: delay in the release of voucher funds, selection criteria used for enrolling pregnant women in the programme, incentives created by the reimbursement system, etc. One of the objectives of the scheme was to encourage market competition among health care providers, but it failed to increase market competitiveness in the area. The resources made available through the scheme did not attract any new providers into the market and public facilities remained the only eligible provider both before and after scheme implementation. However, incentives provided through the voucher system did motivate public providers to offer a higher level of services. The beneficiaries expressed their overall satisfaction with the scheme as well. Since the local facility was not technically ready to provide all types of maternal health care services, providing vouchers may not improve access to care for many pregnant women. To improve the performance of the demand-side strategy, it has become important to adopt some supply-side interventions. In poor developing countries, a demand-side strategy may not be very effective without significant expansion of the service delivery capacity of health facilities at the sub-district level.
Subramanian, S V; Mejía-Guevara, Iván; Krishna, Aditi
2016-05-01
Stunting and chronic undernutrition among children in South Asia remain a major unresolved global health issue. There are compelling intrinsic and moral reasons to ensure that children attain their optimal growth potential facilitated via promotion of healthy living conditions. Investments in efforts to ensure that children's growth is not faltered also have substantial instrumental benefits in terms of cognitive and economic development. Using the case of India, we critique three prevailing approaches to reducing undernutrition among children: an over-reliance on macroeconomic growth as a potent policy instrument, a disproportionate focus on interpreting undernutrition as a demand-side problem and an over-reliance on unintegrated single-factorial (one at a time) approaches to policy and research. Using existing evidence, we develop a case for support-led policy approach with a focus on integrated and structural factors to addressing the problem of undernutrition among children in India. Key messages Eliminating child undernutrition is important from an intrinsic perspective and offers considerable instrumental benefits to individual and society. Evidence suggests that an exclusive reliance on a growth-mediated strategy to eliminate stunting needs to be reconsidered, suggesting the need for a substantial support-led strategy. Interpreting and addressing undernutrition as a demand-side problem with proximal single-factorial interventions is futile. There is an urgent need to develop interventions that address the broader structural and upstream causes of child undernutrition. © 2016 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.
Reduced-Order Models for Load Management in the Power Grid
NASA Astrophysics Data System (ADS)
Alizadeh, Mahnoosh
In recent years, considerable research efforts have been directed towards designing control schemes that can leverage the inherent flexibility of electricity demand that is not tapped into in today's electricity markets. It is expected that these control schemes will be carried out by for-profit entities referred to as aggregators that operate at the edge of the power grid network. While the aggregator control problem is receiving much attention, more high-level questions of how these aggregators should plan their market participation, interact with the main grid and with each other, remain rather understudied. Answering these questions requires a large-scale model for the aggregate flexibility that can be harnessed from the a population of customers, particularly for residences and small businesses. The contribution of this thesis towards this goal is divided into three parts: In Chapter 3, a reduced-order model for a large population of heterogeneous appliances is provided by clustering load profiles that share similar degrees of freedom together. The use of such reduced-order model for system planning and optimal market decision making requires a foresighted approximation of the number of appliances that will join each cluster. Thus, Chapter 4 provides a systematic framework to generate such forecasts for the case of Electric Vehicles, based on real-world battery charging data. While these two chapters set aside the economic side that is naturally involved with participation in demand response programs and mainly focus on the control problem, Chapter 5 is dedicated to the study of optimal pricing mechanisms in order to recruit heterogeneous customers in a demand response program in which an aggregator can directly manage their appliances' load under their specified preferences. Prices are proportional to the wholesale market savings that can result from each recruitment event.
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.
NASA Astrophysics Data System (ADS)
Cao, Jin; Jiang, Zhibin; Wang, Kangzhou
2017-07-01
Many nonlinear customer satisfaction-related factors significantly influence the future customer demand for service-oriented manufacturing (SOM). To address this issue and enhance the prediction accuracy, this article develops a novel customer demand prediction approach for SOM. The approach combines the phase space reconstruction (PSR) technique with the optimized least square support vector machine (LSSVM). First, the prediction sample space is reconstructed by the PSR to enrich the time-series dynamics of the limited data sample. Then, the generalization and learning ability of the LSSVM are improved by the hybrid polynomial and radial basis function kernel. Finally, the key parameters of the LSSVM are optimized by the particle swarm optimization algorithm. In a real case study, the customer demand prediction of an air conditioner compressor is implemented. Furthermore, the effectiveness and validity of the proposed approach are demonstrated by comparison with other classical predication approaches.
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
NASA Astrophysics Data System (ADS)
Khoshaim, Ahmed Bakr
The demand for Silicon Carbide ceramics (SiC) has increased significantly in the last decade due to its reliable physical and chemical properties. The silicon carbide is widely used for aerospace segments in addition to many uses in the industry. Sometimes, a single side grinding is preferable than conventional grinding, for it has the ability to produce flat ceramics. However, the manufacturing cost is still high because of the high tool wear and long machining time. Part of the solution is to use electrolytic in process dressing (ELID) to reduce the processing time. The study on ELID single side grinding of ceramics has never been attempted before. The study involves four variables with three levels each. One of the variables, which is the eccentricity, is being investigated for the first time on ceramics. A full factorial design, for both the surface roughness and material removal rate, guides to calculate mathematical models that can predict future results. Three grinding wheel mesh sizes are used. An investigation of the influence of different grain size on the results can then be evaluated. The kinematics of the process was studied based on eccentricity in order to optimize the pattern of the diamond grains. The experiment is performed with the assist of the proposed specialized ELID fluid, TRIM C270E.
Optimising technical skills and physical loading in small-sided basketball games.
Klusemann, Markus J; Pyne, David B; Foster, Carl; Drinkwater, Eric J
2012-01-01
Differences in physiological, physical, and technical demands of small-sided basketball games related to the number of players, court size, and work-to-rest ratios are not well characterised. A controlled trial was conducted to compare the influence of number of players (2v2/4v4), court size (half/full court) and work-to-rest ratios (4x2.5 min/2x5 min) on the demands of small-sided games. Sixteen elite male and female junior players (aged 15-19 years) completed eight variations of a small-sided game in randomised order over a six-week period. Heart rate responses and rating of perceived exertion (RPE) were measured to assess the physiological load. Movement patterns and technical elements were assessed by video analysis. There were ∼60% more technical elements in 2v2 and ∼20% more in half court games. Heart rate (86 ± 4% & 83 ± 5% of maximum; mean ± SD) and RPE (8 ± 2 & 6 ± 2; scale 1-10) were moderately higher in 2v2 than 4v4 small-sided games, respectively. The 2v2 format elicited substantially more sprints (36 ±12%; mean ±90% confidence limits) and high intensity shuffling (75 ±17%) than 4v4. Full court games required substantially more jogging (9 ±6%) compared to half court games. Fewer players in small-sided basketball games substantially increases the technical, physiological and physical demands.
NASA Astrophysics Data System (ADS)
Yuniar, S.; Wangsaputra, R.; Sinaga, A. T.
2018-03-01
This study aims to develop a combined economical lot size model between supplier and manufacturer for imperfect production processes with probabilistic demand patterns and constant lead times. The supplier side produces the product within a certain time interval then sent to the manufacturer with a certain amount of lot size. Imperfect supplier production systems are characterized by the probability of defective product (γ). The model decision variables are the lot size of the manufacturer's ordering, supplier lot size, and the reorder point of the manufacturer. The optimal decision variables are obtained by minimizing the total expected cost of the combined costs between the suppliers and the manufacturers borne by both parties. The model is built compared to the transactional partnership model, in which the supplier does not participate in the efficiency of its inventory system. A numerical example is given as an illustration of the JELS model and the transactional partnership model. Sensitivity analysis of the model is done by changing the parameters aimed at analyzing the behavior of the developed model.
Development of a pump-turbine runner based on multiobjective optimization
NASA Astrophysics Data System (ADS)
Xuhe, W.; Baoshan, Z.; Lei, T.; Jie, Z.; Shuliang, C.
2014-03-01
As a key component of reversible pump-turbine unit, pump-turbine runner rotates at pump or turbine direction according to the demand of power grid, so higher efficiencies under both operating modes have great importance for energy saving. In the present paper, a multiobjective optimization design strategy, which includes 3D inverse design method, CFD calculations, response surface method (RSM) and multiobjective genetic algorithm (MOGA), is introduced to develop a model pump-turbine runner for middle-high head pumped storage plant. Parameters that controlling blade shape, such as blade loading and blade lean angle at high pressure side are chosen as input parameters, while runner efficiencies under both pump and turbine modes are selected as objective functions. In order to validate the availability of the optimization design system, one runner configuration from Pareto front is manufactured for experimental research. Test results show that the highest unit efficiency is 91.0% under turbine mode and 90.8% under pump mode for the designed runner, of which prototype efficiencies are 93.88% and 93.27% respectively. Viscous CFD calculations for full passage model are also conducted, which aim at finding out the hydraulic improvement from internal flow analyses.
An integrative assessment of the commercial air transportation system via adaptive agents
NASA Astrophysics Data System (ADS)
Lim, Choon Giap
The overarching research objective is to address the tightly-coupled interactions between the demand-side and supply-side components of the United States Commercial Air Transportation System (CATS) in a time-variant environment. A system-of-system perspective is adopted, where the scope is extended beyond the National Airspace System (NAS) level to the National Transportation System (NTS) level to capture the intermodal and multimodal relationships between the NTS stakeholders. The Agent-Based Modeling and Simulation technique is employed where the NTS/NAS is treated as an integrated Multi-Agent System comprising of consumer and service provider agents, representing the demand-side and supply-side components respectively. Successful calibration and validation of both model components against the observable real world data resulted in a CATS simulation tool where the aviation demand is estimated from socioeconomic and demographic properties of the population instead of merely based on enplanement growth multipliers. This valuable achievement enabled a 20-year outlook simulation study to investigate the implications of a global fuel price hike on the airline industry and the U.S. CATS at large. Simulation outcomes revealed insights into the airline competitive behaviors and the subsequent responses from transportation consumers.
The Viability of Commodity Cartels: The Case of Oil.
ERIC Educational Resources Information Center
Bergeijk, Peter A. G. van
1989-01-01
Explains the rise and fall of the oil cartel by applying an elasticity of demand analysis. Beginning from the demand side of the market, offers a simple derivation of the elasticity of demand for the cartel's product. Maintains that method helps undergraduates comprehend basic properties, requiring only an understanding of the elasticities of…
10 CFR 905.15 - What are the requirements for the small customer plan alternative?
Code of Federal Regulations, 2011 CFR
2011-01-01
... all reasonable opportunities to meet future energy service requirements using demand-side management... applicable, and contact person; (ii) Type of customer; (iii) Current energy and demand profiles and data on... and demand use for end-use customers; (iv) Future energy services projections; (v) How items in...
NASA Astrophysics Data System (ADS)
Qiu, Shi.; Tang, Zhuang; Deng, Linghui; Liu, Liangren; Han, Ping; Yang, Lu; Wei, Qiang
2016-09-01
Phosphodiesterase type-5 inhibitors (PDE5-Is) have been recommended as first line therapy for erectile dysfunction for patients received nerve-sparing radical prostatectomy for prostate cancer. We examed the efficiency of PDE5-Is and considered the optimal application. Systematic search of PubMed, Embase and the Cochrane Library was performed to identify all the studies. We identified 103 studies including 3175 patients, of which 14 were recruited for systematic review. Compared with placebo, PDE5-Is significantly ameliorated the International Index of Erectile Function-Erectile Function domain score (IIEF) scores (MD 4.89, 95% CI 4.25-5.53, p < 0.001). By network meta-analysis, sildenafil seems to be the most efficiency with a slightly higher rate of treatment-emergent adverse events (TEATs), whereas tadalafil had the lowest TEATs. In terms of IIEF scores, regular regimen was remarkably better than on-demand (MD 3.28, 95% CI 1.67-4.89, p < 0.001). Regular use was not associated with higher proportion of patients suffering TEATs compared with on-demand (RR 1.02, 95% CI 0.90-1.16, p = 0.72). Compared with placebo, PDE5-Is manifested significantly improved treatment outcomes. Overall, regular regimen demonstrated statistically pronounced better potency than on-demand. Coupled with the comparable rate of side effects, these findings support the regular delivery procedure to be a cost-effective option for patients.
[Family practitioners in Switzerland by 2030: which roles for medical task delegation?].
Jaccard Ruedin, Hélène; Seematter-Bagnoud, Laurence; Roth, Maik; Junod, Julien; Santos-Eggimann, Brigitte
2009-01-01
Due to population aging, by 2030 Switzerland may face a demand of 24 million family practitioner visits, a growth of 13 percent from the 2005 level. This result is based on the assumption that the per capita demand for doctor visits remains what was observed in 2005 by age groups and sex. During the same period, the total number of practitioners may decrease by 14 percent whereas the female proportion of such practitioners may double. These changes may cause a 33 percent decrease in the supply of physician visits to reach only 14 millions. The comparison of the demand and supply of family doctor visits reveals that by 2030, 10 million visits may be unmet which represents 40 percent of the demand. On the supply side, a full scale implementation of task delegation may partially reduce that gap (minus 2 millions). On the demand side, improved health status may bring in a larger decrease in the needs for visits (minus 4 million).
A distributed algorithm for demand-side management: Selling back to the grid.
Latifi, Milad; Khalili, Azam; Rastegarnia, Amir; Zandi, Sajad; Bazzi, Wael M
2017-11-01
Demand side energy consumption scheduling is a well-known issue in the smart grid research area. However, there is lack of a comprehensive method to manage the demand side and consumer behavior in order to obtain an optimum solution. The method needs to address several aspects, including the scale-free requirement and distributed nature of the problem, consideration of renewable resources, allowing consumers to sell electricity back to the main grid, and adaptivity to a local change in the solution point. In addition, the model should allow compensation to consumers and ensurance of certain satisfaction levels. To tackle these issues, this paper proposes a novel autonomous demand side management technique which minimizes consumer utility costs and maximizes consumer comfort levels in a fully distributed manner. The technique uses a new logarithmic cost function and allows consumers to sell excess electricity (e.g. from renewable resources) back to the grid in order to reduce their electric utility bill. To develop the proposed scheme, we first formulate the problem as a constrained convex minimization problem. Then, it is converted to an unconstrained version using the segmentation-based penalty method. At each consumer location, we deploy an adaptive diffusion approach to obtain the solution in a distributed fashion. The use of adaptive diffusion makes it possible for consumers to find the optimum energy consumption schedule with a small number of information exchanges. Moreover, the proposed method is able to track drifts resulting from changes in the price parameters and consumer preferences. Simulations and numerical results show that our framework can reduce the total load demand peaks, lower the consumer utility bill, and improve the consumer comfort level.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Potter, Jennifer; Stuart, Elizabeth; Cappers, P
Integrated demand-side management (IDSM) is a strategic approach to designing and delivering a portfolio of demand side management (DSM) programs to customers. IDSM typically delivers customer centric strategies with the goal of increasing the amount of DSM in the field, but doing so in a way that integrates various measures and technologies to improve their collective performance and/or penetration. Specifically, IDSM can be defined as the integrated or coordinated delivery of three or more of: (1) energy efficiency (EE), (2) demand response (DR), (3) distributed generation (DG), (4) storage, (5) electric vehicle (EV) technologies, and (6) time-based rate programs tomore » residential and commercial electric utility customers. The electric industry’s limited experience deploying IDSM to date suggests that significant barriers may exist. A Berkeley Lab report “Barriers and Opportunities to Broader Adoption of Integrated Demand Side Management at Electric Utilities: A Scoping Study” explores recent electric utility experience with IDSM to provide an assessment of the barriers and potential benefits perceived or experienced by program administrators in their attempts to implement integrated programs. The research draws on surveys and interviews with eleven staff from a sample of eight DSM program administrators and program implementers who were currently implementing or had previously attempted to implement an IDSM program or initiative. Respondents provided their perspectives on drivers for IDSM and barriers to broader deployment. They also reported on actions they had undertaken to promote expanded delivery of IDSM and provided their assessments of the most important under-tapped opportunities for expanding IDSM efforts, both for program administrator and regulatory organizations.« less
Effects of dynamic-demand-control appliances on the power grid frequency.
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.
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.
Uchida, Emi; Swallow, Stephen K; Gold, Arthur; Opaluch, James; Kafle, Achyut; Merrill, Nathaniel; Michaud, Clayton; Gill, Carrie Anne
2018-04-01
Innovative market mechanisms are being increasingly recognized as effective decision-making institutions to incorporate the value of ecosystem services into the economy. We present a field experiment that integrates an economic auction and a biophysical water flux model to develop a local market process consisting of both the supply and demand sides. On the supply side, we operate an auction with small-scale livestock owners who bid for contracts to implement site-specific manure management practices that reduce phosphorus loadings to a major reservoir. On the demand side, we implement a real money, multi-unit public good auction for these contracts with residents who potentially benefit from reduced water quality risks. The experiments allow us to construct supply and demand curves to find an equilibrium price for water quality improvement. The field experiments provide a proof-of-concept for practical implementation of a local market for environmental improvements, even for the challenging context of nonpoint pollution.
Promoting innovation in small markets: Evidence from the market for rare and intractable diseases.
Iizuka, Toshiaki; Uchida, Gyo
2017-07-01
In many medical care markets with limited profit potential, firms often have little incentive to innovate. These include the market for rare diseases, "neglected" tropical diseases, and personalized medicine. Governments and not-for-profit organizations promote innovation in such markets but empirical evidence on the policy effect is limited. We study this issue by analyzing the impact of a demand-side policy in Japan, which reduces the cost sharing of patients with some rare and intractable diseases and attempts to establish and promote the treatment of those diseases. Using clinical trials data taken from public registries, we identify the effect of the policy using a difference-in-difference approach. We find that the demand-side policy increased firms' incentive to innovate: firm-sponsored clinical trials increased 181% (0.16 per disease per year) when covered by the policy. This result indicates that the demand-side policy can be an important part of innovation policies in markets with limited profit potential. Copyright © 2017 Elsevier B.V. All rights reserved.
Increasing the demand for childhood vaccination in developing countries: a systematic review
2009-01-01
Background Attempts to maintain or increase vaccination coverage almost all focus on supply side interventions: improving availability and delivery of vaccines. The effectiveness and cost-effectiveness of efforts to increase demand is uncertain. Methods We performed a systematic review of studies that provided quantitative estimates of the impact of demand side interventions on uptake of routine childhood vaccination. We retrieved studies published up to Sept 2008. Results The initial search retrieved 468 potentially eligible studies, including four systematic reviews and eight original studies of the impact of interventions to increase demand for vaccination. We identified only two randomised controlled trials. Interventions with an impact on vaccination uptake included knowledge translation (KT) (mass media, village resource rooms and community discussions) and non-KT initiatives (incentives, economic empowerment, household visits by extension workers). Most claimed to increase vaccine coverage by 20 to 30%. Estimates of the cost per vaccinated child varied considerably with several in the range of $10-20 per vaccinated child. Conclusion Most studies reviewed here represented a low level of evidence. Mass media campaigns may be effective, but the impact depends on access to media and may be costly if run at a local level. The persistence of positive effects has not been investigated. The economics of demand side interventions have not been adequately assessed, but available data suggest that some may be very cost-effective. PMID:19828063
Heuristics for Multiobjective Optimization of Two-Sided Assembly Line Systems
Jawahar, N.; Ponnambalam, S. G.; Sivakumar, K.; Thangadurai, V.
2014-01-01
Products such as cars, trucks, and heavy machinery are assembled by two-sided assembly line. Assembly line balancing has significant impacts on the performance and productivity of flow line manufacturing systems and is an active research area for several decades. This paper addresses the line balancing problem of a two-sided assembly line in which the tasks are to be assigned at L side or R side or any one side (addressed as E). Two objectives, minimum number of workstations and minimum unbalance time among workstations, have been considered for balancing the assembly line. There are two approaches to solve multiobjective optimization problem: first approach combines all the objectives into a single composite function or moves all but one objective to the constraint set; second approach determines the Pareto optimal solution set. This paper proposes two heuristics to evolve optimal Pareto front for the TALBP under consideration: Enumerative Heuristic Algorithm (EHA) to handle problems of small and medium size and Simulated Annealing Algorithm (SAA) for large-sized problems. The proposed approaches are illustrated with example problems and their performances are compared with a set of test problems. PMID:24790568
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
NASA Astrophysics Data System (ADS)
Chaerani, D.; Lesmana, E.; Tressiana, N.
2018-03-01
In this paper, an application of Robust Optimization in agricultural water resource management problem under gross margin and water demand uncertainty is presented. Water resource management is a series of activities that includes planning, developing, distributing and managing the use of water resource optimally. Water resource management for agriculture can be one of the efforts to optimize the benefits of agricultural output. The objective function of agricultural water resource management problem is to maximizing total benefits by water allocation to agricultural areas covered by the irrigation network in planning horizon. Due to gross margin and water demand uncertainty, we assume that the uncertain data lies within ellipsoidal uncertainty set. We employ robust counterpart methodology to get the robust optimal solution.
Optimal pricing policies for services with consideration of facility maintenance costs
NASA Astrophysics Data System (ADS)
Yeh, Ruey Huei; Lin, Yi-Fang
2012-06-01
For survival and success, pricing is an essential issue for service firms. This article deals with the pricing strategies for services with substantial facility maintenance costs. For this purpose, a mathematical framework that incorporates service demand and facility deterioration is proposed to address the problem. The facility and customers constitute a service system driven by Poisson arrivals and exponential service times. A service demand with increasing price elasticity and a facility lifetime with strictly increasing failure rate are also adopted in modelling. By examining the bidirectional relationship between customer demand and facility deterioration in the profit model, the pricing policies of the service are investigated. Then analytical conditions of customer demand and facility lifetime are derived to achieve a unique optimal pricing policy. The comparative statics properties of the optimal policy are also explored. Finally, numerical examples are presented to illustrate the effects of parameter variations on the optimal pricing policy.
Intelligent and robust optimization frameworks for smart grids
NASA Astrophysics Data System (ADS)
Dhansri, Naren Reddy
A smart grid implies a cyberspace real-time distributed power control system to optimally deliver electricity based on varying consumer characteristics. Although smart grids solve many of the contemporary problems, they give rise to new control and optimization problems with the growing role of renewable energy sources such as wind or solar energy. Under highly dynamic nature of distributed power generation and the varying consumer demand and cost requirements, the total power output of the grid should be controlled such that the load demand is met by giving a higher priority to renewable energy sources. Hence, the power generated from renewable energy sources should be optimized while minimizing the generation from non renewable energy sources. This research develops a demand-based automatic generation control and optimization framework for real-time smart grid operations by integrating conventional and renewable energy sources under varying consumer demand and cost requirements. Focusing on the renewable energy sources, the intelligent and robust control frameworks optimize the power generation by tracking the consumer demand in a closed-loop control framework, yielding superior economic and ecological benefits and circumvent nonlinear model complexities and handles uncertainties for superior real-time operations. The proposed intelligent system framework optimizes the smart grid power generation for maximum economical and ecological benefits under an uncertain renewable wind energy source. The numerical results demonstrate that the proposed framework is a viable approach to integrate various energy sources for real-time smart grid implementations. The robust optimization framework results demonstrate the effectiveness of the robust controllers under bounded power plant model uncertainties and exogenous wind input excitation while maximizing economical and ecological performance objectives. Therefore, the proposed framework offers a new worst-case deterministic optimization algorithm for smart grid automatic generation control.
2014-01-01
Background Demand-side financing, where funds for specific services are channelled through, or to, prospective users, is now employed in health and education sectors in many low- and middle-income countries. This systematic review aimed to critically examine the evidence on application of this approach to promote maternal health in these settings. Five modes were considered: unconditional cash transfers, conditional cash transfers, short-term payments to offset costs of accessing maternity services, vouchers for maternity services, and vouchers for merit goods. We sought to assess the effects of these interventions on utilisation of maternity services and on maternal health outcomes and infant health, the situation of underprivileged women and the healthcare system. Methods The protocol aimed for collection and synthesis of a broad range of evidence from quantitative, qualitative and economic studies. Nineteen health and social policy databases, seven unpublished research databases and 27 websites were searched; with additional searches of Indian journals and websites. Studies were included if they examined demand-side financing interventions to increase consumption of services or goods intended to impact on maternal health, and met relevant quality criteria. Quality assessment, data extraction and analysis used Joanna Briggs Institute standardised tools and software. Outcomes of interest included maternal and infant mortality and morbidity, service utilisation, factors required for successful implementation, recipient and provider experiences, ethical issues, and cost-effectiveness. Findings on Effectiveness, Feasibility, Appropriateness and Meaningfulness were presented by narrative synthesis. Results Thirty-three quantitative studies, 46 qualitative studies, and four economic studies from 17 countries met the inclusion criteria. Evidence on unconditional cash transfers was scanty. Other demand-side financing modes were found to increase utilisation of maternal healthcare in the index pregnancy or uptake of related merit goods. Evidence of effects on maternal and infant mortality and morbidity outcomes was insufficient. Important implementation aspects include targeting and eligibility criteria, monitoring, respectful treatment of beneficiaries, suitable incentives for providers, quality of care and affordable referral systems. Conclusions Demand-side financing schemes can increase utilisation of maternity services, but attention must be paid to supply-side conditions, the fine-grain of implementation and sustainability. Comparative studies and research on health impact and cost-effectiveness are required. PMID:24438560
Murray, Susan F; Hunter, Benjamin M; Bisht, Ramila; Ensor, Tim; Bick, Debra
2014-01-17
Demand-side financing, where funds for specific services are channelled through, or to, prospective users, is now employed in health and education sectors in many low- and middle-income countries. This systematic review aimed to critically examine the evidence on application of this approach to promote maternal health in these settings. Five modes were considered: unconditional cash transfers, conditional cash transfers, short-term payments to offset costs of accessing maternity services, vouchers for maternity services, and vouchers for merit goods. We sought to assess the effects of these interventions on utilisation of maternity services and on maternal health outcomes and infant health, the situation of underprivileged women and the healthcare system. The protocol aimed for collection and synthesis of a broad range of evidence from quantitative, qualitative and economic studies. Nineteen health and social policy databases, seven unpublished research databases and 27 websites were searched; with additional searches of Indian journals and websites. Studies were included if they examined demand-side financing interventions to increase consumption of services or goods intended to impact on maternal health, and met relevant quality criteria. Quality assessment, data extraction and analysis used Joanna Briggs Institute standardised tools and software. Outcomes of interest included maternal and infant mortality and morbidity, service utilisation, factors required for successful implementation, recipient and provider experiences, ethical issues, and cost-effectiveness. Findings on Effectiveness, Feasibility, Appropriateness and Meaningfulness were presented by narrative synthesis. Thirty-three quantitative studies, 46 qualitative studies, and four economic studies from 17 countries met the inclusion criteria. Evidence on unconditional cash transfers was scanty. Other demand-side financing modes were found to increase utilisation of maternal healthcare in the index pregnancy or uptake of related merit goods. Evidence of effects on maternal and infant mortality and morbidity outcomes was insufficient. Important implementation aspects include targeting and eligibility criteria, monitoring, respectful treatment of beneficiaries, suitable incentives for providers, quality of care and affordable referral systems. Demand-side financing schemes can increase utilisation of maternity services, but attention must be paid to supply-side conditions, the fine-grain of implementation and sustainability. Comparative studies and research on health impact and cost-effectiveness are required.
Gopalan, Saji S; Durairaj, Varatharajan
2012-09-15
Demand side financing (DSF) is a widely employed strategy to enhance utilization of healthcare. The impact of DSF on health care seeking in general and that of maternal care in particular is already known. Yet, its effect on financial access to care, out-of-pocket spending (OOPS) and provider motivations is not considerably established. Without such evidence, DSFs may not be recommendable to build up any sustainable healthcare delivery approach. This study explores the above aspects on India's Janani Suraksha Yojana (JSY) program. This study employed design and was conducted in three districts of Orissa, selected through a three-stage stratified sampling. The quantitative method was used to review the Health Management Information System (HMIS). The qualitative methods included focus groups discussions with beneficiaries (n = 19) and community intermediaries (n = 9), and interviews (n = 7) with Ministry of Health officials. HMIS data enabled to review maternal healthcare utilization. Group discussions and interviews explored the perceived impact of JSY on in-facility delivery, OOPS, healthcare costs, quality of care and performance motivation of community health workers. The number of institutional deliveries, ante-and post-natal care visits increased after the introduction of JSY with an annual net growth of 18.1%, 3.6% and 5% respectively. The financial incentive provided partial financial risk-protection as it could cover only 25.5% of the maternal healthcare cost of the beneficiaries in rural areas and 14.3% in urban areas. The incentive induced fresh out-of-pocket spending for some mothers and it could not address maternal care requirements comprehensively. An activity-based community worker model was encouraging to augment maternal healthcare consumption. However, the existing level of financial incentives and systemic support were inadequate to motivate the volunteers optimally on their performance. Demand side financial incentive could enhance financial access to maternal healthcare. However, it did not adequately protect households from financial risks. An effective integration of JSY with similar social protection or financial risk-protection measures may protect mothers substantially from potential out-of-pocket spending. Further, this integrated approach may help upholding more awareness on maternal health rights and entitlements. It can also address maternal health beyond 'maternal healthcare' and ensure sustainability through pooled financial and non-financial resources.
ERIC Educational Resources Information Center
American Fletcher National Bank and Trust Co., Indianapolis, IN.
Designed for high school economics students as a public service project of the American Fletcher National Bank, the booklet examines the "supply-side" philosophy of economics of the Reagan Administration as compared to the "demand-side" emphasis of the past. The manipulation of the nation's economy by raising or lowering…
Climate change impacts on high-elevation hydroelectricity in California
NASA Astrophysics Data System (ADS)
Madani, Kaveh; Guégan, Marion; Uvo, Cintia B.
2014-03-01
While only about 30% of California's usable water storage capacity lies at higher elevations, high-elevation (above 300 m) hydropower units generate, on average, 74% of California's in-state hydroelectricity. In general, high-elevation plants have small man-made reservoirs and rely mainly on snowpack. Their low built-in storage capacity is a concern with regard to climate warming. Snowmelt is expected to shift to earlier in the year, and the system may not be able to store sufficient water for release in high-demand periods. Previous studies have explored the climate warming effects on California's high-elevation hydropower by focusing on the supply side (exploring the effects of hydrological changes on generation and revenues) ignoring the warming effects on hydroelectricity demand and pricing. This study extends the previous work by simultaneous consideration of climate change effects on high-elevation hydropower supply and pricing in California. The California's Energy-Based Hydropower Optimization Model (EBHOM 2.0) is applied to evaluate the adaptability of California's high-elevation hydropower system to climate warming, considering the warming effects on hydroelectricity supply and pricing. The model's results relative to energy generation, energy spills, reservoir energy storage, and average shadow prices of energy generation and storage capacity expansion are examined and discussed. These results are compared with previous studies to emphasize the need to consider climate change effects on hydroelectricity demand and pricing when exploring the effects of climate change on hydropower operations.
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
Potential of a precrash lateral occupant movement in side collisions of (electric) minicars.
Hierlinger, T; Lienkamp, M; Unger, J; Unselt, T
2015-01-01
In minicars, the survival space between the side structure and occupant is smaller than in conventional cars. This is an issue in side collisions. Therefore, in this article a solution is studied in which a lateral seat movement is imposed in the precrash phase. It generates a pre-acceleration and an initial velocity of the occupant, thus reducing the loads due to the side impact. The assessment of the potential is done by numerical simulations and a full-vehicle crash test. The optimal parameters of the restraint system including the precrash movement, time-to-fire of head and side airbag, etc., are found using metamodel-based optimization methods by minimizing occupant loads according to European New Car Assessment Programme (Euro NCAP). The metamodel-based optimization approach is able to tune the restraint system parameters. The numerical simulations show a significant averaged reduction of 22.3% in occupant loads. The results show that the lateral precrash occupant movement offers better occupant protection in side collisions.
NASA Astrophysics Data System (ADS)
Ebrahimnejad, Ali
2015-08-01
There are several methods, in the literature, for solving fuzzy variable linear programming problems (fuzzy linear programming in which the right-hand-side vectors and decision variables are represented by trapezoidal fuzzy numbers). In this paper, the shortcomings of some existing methods are pointed out and to overcome these shortcomings a new method based on the bounded dual simplex method is proposed to determine the fuzzy optimal solution of that kind of fuzzy variable linear programming problems in which some or all variables are restricted to lie within lower and upper bounds. To illustrate the proposed method, an application example is solved and the obtained results are given. The advantages of the proposed method over existing methods are discussed. Also, one application of this algorithm in solving bounded transportation problems with fuzzy supplies and demands is dealt with. The proposed method is easy to understand and to apply for determining the fuzzy optimal solution of bounded fuzzy variable linear programming problems occurring in real-life situations.
A stochastic equilibrium model for the North American natural gas market
NASA Astrophysics Data System (ADS)
Zhuang, Jifang
This dissertation is an endeavor in the field of energy modeling for the North American natural gas market using a mixed complementarity formulation combined with the stochastic programming. The genesis of the stochastic equilibrium model presented in this dissertation is the deterministic market equilibrium model developed in [Gabriel, Kiet and Zhuang, 2005]. Based on some improvements that we made to this model, including proving new existence and uniqueness results, we present a multistage stochastic equilibrium model with uncertain demand for the deregulated North American natural gas market using the recourse method of the stochastic programming. The market participants considered by the model are pipeline operators, producers, storage operators, peak gas operators, marketers and consumers. Pipeline operators are described with regulated tariffs but also involve "congestion pricing" as a mechanism to allocate scarce pipeline capacity. Marketers are modeled as Nash-Cournot players in sales to the residential and commercial sectors but price-takers in all other aspects. Consumers are represented by demand functions in the marketers' problem. Producers, storage operators and peak gas operators are price-takers consistent with perfect competition. Also, two types of the natural gas markets are included: the long-term and spot markets. Market participants make both high-level planning decisions (first-stage decisions) in the long-term market and daily operational decisions (recourse decisions) in the spot market subject to their engineering, resource and political constraints, resource constraints as well as market constraints on both the demand and the supply side, so as to simultaneously maximize their expected profits given others' decisions. The model is shown to be an instance of a mixed complementarity problem (MiCP) under minor conditions. The MiCP formulation is derived from applying the Karush-Kuhn-Tucker optimality conditions of the optimization problems faced by the market participants. Some theoretical results regarding the market prices in both markets are shown. We also illustrate the model on a representative, sample network of two production nodes, two consumption nodes with discretely distributed end-user demand and three seasons using four cases.
NASA Astrophysics Data System (ADS)
Ines, A.; Bhattacharjee, A.; Modi, V.; Robertson, A. W.; Lall, U.; Kocaman Ayse, S.; Chaudhary, S.; Kumar, A.; Ganapathy, A.; Kumar, A.; Mishra, V.
2015-12-01
Energy demand management, also known as demand side management (DSM), is the modification of consumer demand for energy through various methods such as smart metering, incentive based schemes, payments for turning off loads or rescheduling loads. Usually, the goal of demand side management is to encourage the consumer to use less power during periods of peak demand, or to move the time of energy use to off-peak times. Peak demand management does not necessarily decrease total energy consumption, but could be expected to reduce the need for investments in networks and/or power plants for meeting peak demands. Electricity use can vary dramatically on short and medium time frames, and the pricing system may not reflect the instantaneous cost as additional higher-cost that are brought on-line. In addition, the capacity or willingness of electricity consumers to adjust to prices by altering elasticity of demand may be low, particularly over short time frames. In the scenario of Indian grid setup, the retail customers do not follow real-time pricing and it is difficult to incentivize the utility companies for continuing the peak demand supply. A question for the future is how deeper penetration of renewable will be handled? This is a challenging problem since one has to deal with high variability, while managing loss of load probabilities. In the case of managing the peak demand using agriculture, in the future as smart metering matures with automatic turn on/off for a pump, it will become possible to provide an ensured amount of water or energy to the farmer while keeping the grid energized for 24 hours. Supply scenarios will include the possibility of much larger penetration of solar and wind into the grid. While, in absolute terms these sources are small contributors, their role will inevitably grow but DSM using agriculture could help reduce the capital cost. The other option is of advancing or delaying pump operating cycle even by several hours, will still ensure soil moisture requirements met while, balancing the overall system load with generation, reducing critical power mismatches. Through this presentation the author will describe different techniques and results from field experiments in India.
DOT National Transportation Integrated Search
1972-07-01
Increasing automation of air traffic control tasks may have the undesirable side effect of increased monotony as a result of the anticipated reduction in task demands. 50 subjects performed a monotonous, but perceptually demanding task, for approxima...
Choudhury, Aziz Ahmed; Khanam, Rasheda; Moin, Syed Mamun Ibne; Ahmed, Salahuddin; Begum, Nazma; Shoma, Nurun Naher; Quaiyum, Md Abdul; Baqui, Abdullah H.
2017-01-01
Background According to the Bangladesh Demographic and Health Survey 2014, only approximately 37 percent of women deliver in a health facility. Among the eight administrative divisions of Bangladesh, the facility delivery rate is lowest in the Sylhet division (22.6 percent) where we assessed the effect of integrated supply- and demand-side interventions on the facility-based delivery rate. Methods Population-based cohort data of pregnant women from an ongoing maternal and newborn health improvement study being conducted in a population of ~120,000 in Sylhet district were used. The study required collection and processing of biological samples immediately after delivery. Therefore, the project assembled various strategies to increase institutional delivery rates. The supply-side intervention included capacity expansion of the health facilities through service provider refresher training, 24/7 service coverage, additions of drugs and supplies, and incentives to the providers. The demand-side component involved financial incentives to cover expenses, a provision of emergency transport, and referral support to a tertiary-level hospital. We conducted a before-and-after observational study to assess the impact of the intervention in a total of 1,861 deliveries between December 2014 and November 2016. Results Overall, implementation of the intervention package was associated with 52.6 percentage point increase in the proportions of facility-based deliveries from a baseline rate of 25.0 percent to 77.6 percent in 24 months. We observed lower rates of institutional deliveries when only supply-side interventions were implemented. The proportion rose to 47.1 percent and continued increasing when the project emphasized addressing the financial barriers to accessing obstetric care in a health facility. Conclusions An integrated supply- and demand-side intervention was associated with a substantial increase in institutional delivery. The package can be tailored to identify which combination of interventions may produce the optimum result and be scaled. Rigorous implementation research studies are needed to draw confident conclusions and to provide information about the costs, feasibility for scale-up and sustainability. PMID:29073229
Koltun, G.F.
2001-01-01
This report provides data and methods to aid in the hydrologic design or evaluation of impounding reservoirs and side-channel reservoirs used for water supply in Ohio. Data from 117 streamflow-gaging stations throughout Ohio were analyzed by means of nonsequential-mass-curve-analysis techniques to develop relations between storage requirements, water demand, duration, and frequency. Information also is provided on minimum runoff for selected durations and frequencies. Systematic record lengths for the streamflow-gaging stations ranged from about 10 to 75 years; however, in many cases, additional streamflow record was synthesized. For impounding reservoirs, families of curves are provided to facilitate the estimation of storage requirements as a function of demand and the ratio of the 7-day, 2-year low flow to the mean annual flow. Information is provided with which to evaluate separately the effects of evaporation on storage requirements. Comparisons of storage requirements for impounding reservoirs determined by nonsequential-mass-curve-analysis techniques with storage requirements determined by annual-mass-curve techniques that employ probability routing to account for carryover-storage requirements indicate that large differences in computed required storages can result from the two methods, particularly for conditions where demand cannot be met from within-year storage. For side-channel reservoirs, tables of demand-storage-frequency information are provided for a primary pump relation consisting of one variable-speed pump with a pumping capacity that ranges from 0.1 to 20 times demand. Tables of adjustment ratios are provided to facilitate determination of storage requirements for 19 other pump sets consisting of assorted combinations of fixed-speed pumps or variable-speed pumps with aggregate pumping capacities smaller than or equal to the primary pump relation. The effects of evaporation on side-channel reservoir storage requirements are incorporated into the storage-requirement estimates. The effects of an instream-flow requirement equal to the 80-percent-duration flow are also incorporated into the storage-requirement estimates.
NASA Astrophysics Data System (ADS)
Mishra, Vinod Kumar
2017-09-01
In this paper we develop an inventory model, to determine the optimal ordering quantities, for a set of two substitutable deteriorating items. In this inventory model the inventory level of both items depleted due to demands and deterioration and when an item is out of stock, its demands are partially fulfilled by the other item and all unsatisfied demand is lost. Each substituted item incurs a cost of substitution and the demands and deterioration is considered to be deterministic and constant. Items are order jointly in each ordering cycle, to take the advantages of joint replenishment. The problem is formulated and a solution procedure is developed to determine the optimal ordering quantities that minimize the total inventory cost. We provide an extensive numerical and sensitivity analysis to illustrate the effect of different parameter on the model. The key observation on the basis of numerical analysis, there is substantial improvement in the optimal total cost of the inventory model with substitution over without substitution.
Empowering leadership and job crafting: The role of employee optimism.
Thun, Sylvi; Bakker, Arnold B
2018-06-08
The objective of this study was to test the relationship between empowering leadership and job crafting and to examine the moderating role of optimism as a personal resource. We hypothesized that the association between empowering leadership and job crafting would be stronger for employees with high (vs. low) levels of optimism. A total of 331 Norwegian workers from a variety of occupations participated in our study. Results of structural equation modelling analysis generally supported our hypotheses. Empowering leadership was positively related to 3 of the 4 job crafting strategies investigated (increasing structural job resources, increasing social job resources, and increasing challenging job demands; but not reducing hindrance job demands). Moreover, as hypothesized, optimism strengthened the empowering leadership-job crafting relationship for increasing structural resources and increasing challenging demands. The results suggest that empowering leadership is an important antecedent of job crafting strategies, except for reducing hindrance demands. The implications of these findings are discussed. Copyright © 2018 John Wiley & Sons, Ltd.
Design of limited-stop service based on the degree of unbalance of passenger demand
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
Design of limited-stop service based on the degree of unbalance of passenger demand.
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.
Long-term impacts of battery electric vehicles on the German electricity system
NASA Astrophysics Data System (ADS)
Heinrichs, H. U.; Jochem, P.
2016-05-01
The emerging market for electric vehicles gives rise to an additional electricity demand. This new electricity demand will affect the electricity system. For quantifying those impacts a model-based approach, which covers long-term time horizons is necessary in order to consider the long lasting investment paths in electricity systems and the market development of electric mobility. Therefore, we apply a bottom-up electricity system model showing a detailed spatial resolution for different development paths of electric mobility in Germany until 2030. This model is based on a linear optimization which minimizes the discounted costs of the electricity system. We observe an increase of electricity exchange between countries and electricity generated by renewable energy sources. One major result turns out to be that electric vehicles can be integrated in the electricity system without increasing the system costs when a controlled (postponing) charging strategy for electric vehicles is applied. The impact on the power plant portfolio is insignificant. Another important side effect of electric vehicles is their substantial contribution to decreasing CO2 emissions of the German transport sector. Hence, electric mobility might be an integral part of a sustainable energy system of tomorrow.
A Hierarchical Framework for Demand-Side Frequency Control
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moya, Christian; Zhang, Wei; Lian, Jianming
2014-06-02
With large-scale plans to integrate renewable generation, more resources will be needed to compensate for the uncertainty associated with intermittent generation resources. Under such conditions, performing frequency control using only supply-side resources become not only prohibitively expensive but also technically difficult. It is therefore important to explore how a sufficient proportion of the loads could assume a routine role in frequency control to maintain the stability of the system at an acceptable cost. In this paper, a novel hierarchical decentralized framework for frequency based load control is proposed. The framework involves two decision layers. The top decision layer determines themore » optimal droop gain required from the aggregated load response on each bus using a robust decentralized control approach. The second layer consists of a large number of devices, which switch probabilistically during contingencies so that the aggregated power change matches the desired droop amount according to the updated gains. The proposed framework is based on the classical nonlinear multi-machine power system model, and can deal with timevarying system operating conditions while respecting the physical constraints of individual devices. Realistic simulation results based on a 68-bus system are provided to demonstrate the effectiveness of the proposed strategy.« less
Single-Point Mutation with a Rotamer Library Toolkit: Toward Protein Engineering.
Pottel, Joshua; Moitessier, Nicolas
2015-12-28
Protein engineers have long been hard at work to harness biocatalysts as a natural source of regio-, stereo-, and chemoselectivity in order to carry out chemistry (reactions and/or substrates) not previously achieved with these enzymes. The extreme labor demands and exponential number of mutation combinations have induced computational advances in this domain. The first step in our virtual approach is to predict the correct conformations upon mutation of residues (i.e., rebuilding side chains). For this purpose, we opted for a combination of molecular mechanics and statistical data. In this work, we have developed automated computational tools to extract protein structural information and created conformational libraries for each amino acid dependent on a variable number of parameters (e.g., resolution, flexibility, secondary structure). We have also developed the necessary tool to apply the mutation and optimize the conformation accordingly. For side-chain conformation prediction, we obtained overall average root-mean-square deviations (RMSDs) of 0.91 and 1.01 Å for the 18 flexible natural amino acids within two distinct sets of over 3000 and 1500 side-chain residues, respectively. The commonly used dihedral angle differences were also evaluated and performed worse than the state of the art. These two metrics are also compared. Furthermore, we generated a family-specific library for kinases that produced an average 2% lower RMSD upon side-chain reconstruction and a residue-specific library that yielded a 17% improvement. Ultimately, since our protein engineering outlook involves using our docking software, Fitted/Impacts, we applied our mutation protocol to a benchmarked data set for self- and cross-docking. Our side-chain reconstruction does not hinder our docking software, demonstrating differences in pose prediction accuracy of approximately 2% (RMSD cutoff metric) for a set of over 200 protein/ligand structures. Similarly, when docking to a set of over 100 kinases, side-chain reconstruction (using both general and biased conformation libraries) had minimal detriment to the docking accuracy.
18 CFR 430.13 - Protected area permits for new withdrawals.
Code of Federal Regulations, 2010 CFR
2010-04-01
... space heating or cooling that are subsequently used for commercial or industrial water supply purposes... against significant leaks of refrigerant, all ground water heat pump systems shall be equipped with an... resource requirements; evaluate supply-side and demand-side alternatives to meet water withdrawal needs...
Decentralization of Education: Demand-Side Financing. Directions in Development.
ERIC Educational Resources Information Center
Patrinos, Harry A.; Ariasingam, David L.
Central governments' supply-side expansions of schooling have not equally benefited all members of society, especially girls, indigenous peoples, tribal groups, disadvantaged minorities, and the poor. Public spending on education is often inefficient, higher education is subsidized at primary education's expense, and costs are becoming…
NASA Astrophysics Data System (ADS)
Fujii, Hidemichi; Okamoto, Shunsuke; Kagawa, Shigemi; Managi, Shunsuke
2017-12-01
This study investigated the changes in the toxicity of chemical emissions from the US industrial sector over the 1998-2009 period. Specifically, we employed a multiregional input-output analysis framework and integrated a supply-side index decomposition analysis (IDA) with a demand-side structural decomposition analysis (SDA) to clarify the main drivers of changes in the toxicity of production- and consumption-based chemical emissions. The results showed that toxic emissions from the US industrial sector decreased by 83% over the studied period because of pollution abatement efforts adopted by US industries. A variety of pollution abatement efforts were used by different industries, and cleaner production in the mining sector and the use of alternative materials in the manufacture of transportation equipment represented the most important efforts.
A System Dynamics Modeling of Water Supply and Demand in Las Vegas Valley
NASA Astrophysics Data System (ADS)
Parajuli, R.; Kalra, A.; Mastino, L.; Velotta, M.; Ahmad, S.
2017-12-01
The rise in population and change in climate have posed the uncertainties in the balance between supply and demand of water. The current study deals with the water management issues in Las Vegas Valley (LVV) using Stella, a system dynamics modeling software, to model the feedback based relationship between supply and demand parameters. Population parameters were obtained from Center for Business and Economic Research while historical water demand and conservation practices were modeled as per the information provided by local authorities. The water surface elevation of Lake Mead, which is the prime source of water supply to the region, was modeled as the supply side whereas the water demand in LVV was modeled as the demand side. The study was done from the period of 1989 to 2049 with 1989 to 2012 as the historical one and the period from 2013 to 2049 as the future period. This study utilizes Coupled Model Intercomparison Project data sets (2013-2049) (CMIP3&5) to model different future climatic scenarios. The model simulates the past dynamics of supply and demand, and then forecasts the future water budget for the forecasted future population and future climatic conditions. The results can be utilized by the water authorities in understanding the future water status and hence plan suitable conservation policies to allocate future water budget and achieve sustainable water management.
A Brief Introduction to the Theory of Friction Stir Welding
NASA Technical Reports Server (NTRS)
Nunes, Arthur C., Jr.
2008-01-01
Friction stir welding (FSW) is a solid state welding process invented in 1991 at The Welding Institute in the United Kingdom. A weld is made in the FSW process by translating a rotating pin along a weld seam so as to stir the sides of the seam together. FSW avoids deleterious effects inherent in melting and is already an important welding process for the aerospace industry, where welds of optimal quality are demanded. The structure of welds determines weld properties. The structure of friction stir welds is determined by the flow field in the weld metal in the vicinity of the weld tool. A simple kinematic model of the FSW flow field developed at Marshall Space Flight Center, which enables the basic features of FSW microstructure to be understood and related to weld process parameters and tool design, is explained.
NASA Astrophysics Data System (ADS)
Sow, C. K.; Fathullah, M.; Nasir, S. M.; Shayfull, Z.; Shazzuan, S.
2017-09-01
This paper discusses on an analysis run via injection moulding process in determination of the optimum processing parameters used for manufacturing side arms of catheters in minimizing the warpage issues. The optimization method used was RSM. Moreover, in this research tries to find the most significant factor affecting the warpage. From the previous literature review,4 most significant parameters on warpage defect was selected. Those parameters were melt temperature, packing time, packing pressure, mould temperature and cooling time. At the beginning, side arm was drawn using software of CATIA V5. Then, software Mouldflow and Design Expert were employed to analyses on the popular warpage issues. After that, GSO artificial intelligence was apply using the mathematical model from Design Expert for more optimization on RSM result. Recommended parameter settings from the simulation work were then compared with the optimization work of RSM and GSO. The result show that the warpage on the side arm was improved by 3.27 %
NASA Astrophysics Data System (ADS)
Yang, Wen; Fung, Richard Y. K.
2014-06-01
This article considers an order acceptance problem in a make-to-stock manufacturing system with multiple demand classes in a finite time horizon. Demands in different periods are random variables and are independent of one another, and replenishments of inventory deviate from the scheduled quantities. The objective of this work is to maximize the expected net profit over the planning horizon by deciding the fraction of the demand that is going to be fulfilled. This article presents a stochastic order acceptance optimization model and analyses the existence of the optimal promising policies. An example of a discrete problem is used to illustrate the policies by applying the dynamic programming method. In order to solve the continuous problems, a heuristic algorithm based on stochastic approximation (HASA) is developed. Finally, the computational results of a case example illustrate the effectiveness and efficiency of the HASA approach, and make the application of the proposed model readily acceptable.
NASA Astrophysics Data System (ADS)
Bando, Shigeru; Watanabe, Hiroki; Asano, Hiroshi; Tsujita, Shinsuke
A methodology was developed to design the number and capacity for each piece of equipment (e.g. gas engines, batteries, thermal storage tanks) in microgrids with combined heat and power systems. We analyzed three types of microgrids; the first one consists of an office building and an apartment, the second one consists of a hospital and an apartment, the third one consists of a hotel, office and retails. In the methodology, annual cost is minimized by considering the partial load efficiency of a gas engine and its scale economy, and the optimal number and capacity of each piece of equipment and the annual operational schedule are determined by using the optimal planning method. Based on calculations using this design methodology, it is found that the optimal number of gas engines is determined by the ratio of bottom to peak of the electricity demand and the ratio of heat to electricity demand. The optimal capacity of a battery required to supply electricity for a limited time during a peak demand period is auxiliary. The thermal storage tank for space cooling and space heating is selected to minimize the use of auxiliary equipment such as a gas absorption chiller.
Conflict and Education Demand in the Basque Region
ERIC Educational Resources Information Center
de Groot, Olaf J.; Goksel, Idil
2011-01-01
The relationship between conflict and education has been studied before. However, previous authors have always focused strongly on the supply-side effects, whereas this article examines the influence of conflict on the demand for education. It is theoretically shown that, under relatively general conditions, individuals living in a conflict area…
Software on Demand: An Early Childhood Numeracy Partnership
ERIC Educational Resources Information Center
Egan, Mike; Hengst, Randy
2012-01-01
In collaboration with preservice elementary teachers and in-service kindergarten teachers, the authors engaged in small-scale, demand-side production of educational software focused on numeracy skills. That is, the authors built applications designed to address children's specific learning needs as they surfaced in the classroom and were…
Importance of food-demand management for climate mitigation
NASA Astrophysics Data System (ADS)
Bajželj, Bojana; Richards, Keith S.; Allwood, Julian M.; Smith, Pete; Dennis, John S.; Curmi, Elizabeth; Gilligan, Christopher A.
2014-10-01
Recent studies show that current trends in yield improvement will not be sufficient to meet projected global food demand in 2050, and suggest that a further expansion of agricultural area will be required. However, agriculture is the main driver of losses of biodiversity and a major contributor to climate change and pollution, and so further expansion is undesirable. The usual proposed alternative--intensification with increased resource use--also has negative effects. It is therefore imperative to find ways to achieve global food security without expanding crop or pastureland and without increasing greenhouse gas emissions. Some authors have emphasized a role for sustainable intensification in closing global `yield gaps' between the currently realized and potentially achievable yields. However, in this paper we use a transparent, data-driven model, to show that even if yield gaps are closed, the projected demand will drive further agricultural expansion. There are, however, options for reduction on the demand side that are rarely considered. In the second part of this paper we quantify the potential for demand-side mitigation options, and show that improved diets and decreases in food waste are essential to deliver emissions reductions, and to provide global food security in 2050.
Intermediary Organizations in Charter School Policy Coalitions: Evidence from New Orleans
ERIC Educational Resources Information Center
DeBray, Elizabeth; Scott, Janelle; Lubienski, Christopher; Jabbar, Huriya
2014-01-01
This article develops a framework for investigating research use, using an "advocacy coalition framework" and the concepts of a "supply side" (mainly organizations) and "demand side" (policymakers). Drawing on interview data and documents from New Orleans about the charter school reforms that have developed there…
Neo-Keynesian Economics Today.
ERIC Educational Resources Information Center
Shackleton, J. R.
1987-01-01
Traces the development of post-Keynesian economic theories and examines the arguments which surround current neo-Keynesian thought. Argues for an eclecticism which recognizes that both supply-side and demand-side factors have a role to play in determining levels of output and employment. Useful charts and diagrams are included. (Author/DH)
Integrating Demand-Side Resources into the Electric Grid: Economic and Environmental Considerations
NASA Astrophysics Data System (ADS)
Fisher, Michael J.
Demand-side resources are taking an increasingly prominent role in providing essential grid services once provided by thermal power plants. This thesis considers the economic feasibility and environmental effects of integrating demand-side resources into the electric grid with consideration given to the diversity of market and environmental conditions that can affect their behavior. Chapter 2 explores the private economics and system-level carbon dioxide reduction when using demand response for spinning reserve. Steady end uses like lighting are more than twice as profitable as seasonal end uses because spinning reserve is needed year-round. Avoided carbon emission damages from using demand response instead of fossil fuel generation for spinning reserve are sufficient to justify incentives for demand response resources. Chapter 3 quantifies the system-level net emissions rate and private economics of behind-the-meter energy storage. Net emission rates are lower than marginal emission rates for power plants and in-line with estimates of net emission rates from grid-level storage. The economics are favorable for many buildings in regions with high demand charges like California and New York, even without subsidies. Future penetration into regions with average charges like Pennsylvania will depend greatly on installation cost reductions and wholesale prices for ancillary services. Chapter 4 outlines a novel econometric model to quantify potential revenues from energy storage that reduces demand charges. The model is based on a novel predictive metric that is derived from the building's load profile. Normalized revenue estimates are independent of the power capacity of the battery holding other performance characteristics equal, which can be used to calculate the profit-maximizing storage size. Chapter 5 analyzes the economic feasibility of flow batteries in the commercial and industrial market. Flow batteries at a 4-hour duration must be less expensive on a dollar per installed kWh basis, often by 20-30%, to break even with shorter duration li-ion or lead-acid despite allowing for deeper depth of discharge and superior cycle life. These results are robust to assumptions of tariff rates, battery round-trip efficiencies, amount of solar generation and whether the battery can participate in the wholesale energy and ancillary services markets.
An optimization framework for measuring spatial access over healthcare networks.
Li, Zihao; Serban, Nicoleta; Swann, Julie L
2015-07-17
Measurement of healthcare spatial access over a network involves accounting for demand, supply, and network structure. Popular approaches are based on floating catchment areas; however the methods can overestimate demand over the network and fail to capture cascading effects across the system. Optimization is presented as a framework to measure spatial access. Questions related to when and why optimization should be used are addressed. The accuracy of the optimization models compared to the two-step floating catchment area method and its variations is analytically demonstrated, and a case study of specialty care for Cystic Fibrosis over the continental United States is used to compare these approaches. The optimization models capture a patient's experience rather than their opportunities and avoid overestimating patient demand. They can also capture system effects due to change based on congestion. Furthermore, the optimization models provide more elements of access than traditional catchment methods. Optimization models can incorporate user choice and other variations, and they can be useful towards targeting interventions to improve access. They can be easily adapted to measure access for different types of patients, over different provider types, or with capacity constraints in the network. Moreover, optimization models allow differences in access in rural and urban areas.
Managed competition in health care and the unfinished agenda
Enthoven, Alain C.
1986-01-01
A market made up of health care financing and delivery plans and individual consumers, without a carefully drawn set of rules to mitigate market failures, and without mediation by collective action on the demand side, cannot produce efficiency and equity. The concept of competition that can achieve these goals, at least to a satisfactory approximation, is managed competition, with intelligent active agents on the demand side, called sponsors, that contract with the competing health care plans and continuously structure and adjust the market to overcome its tendencies to failure. A great deal remains to be done to achieve the goals envisioned by the “procompetition reformers.” PMID:10311922
Demand and supply of emergency help: an economic analysis of Red Cross services.
Hackl, Franz; Pruckner, Gerald Josef
2006-08-01
This paper analyzes supply and demand side characteristics of (voluntary) Red Cross services in Austria. The demand side analysis is based on a contingent valuation study on people's willingness to pay for emergency treatment, transportation services and disaster relief activities. The supply side is identified by a high percentage of volunteers in the Red Cross organization which makes the provision of emergency help at low cost possible. We find that aggregate benefits of Red Cross services exceed their cost of production. Policy conclusions are drawn with respect to future recruitment and funding: whereas intrinsic motivation is important for the decision to volunteer, and financial incentives play a minor role in general, the young Red Cross activists work voluntarily for self-realization reasons and to continue their education. Age-specific recruitment strategies accompanied by word-of-mouth advertising are recommended to address potential volunteers. As long as the volunteering character of Red Cross services will be maintained and cost of production will not go up an increase of funds does not seem necessary in the future. Moreover, a radical change in the structure of funding may crowd out both donations and voluntary labor supply.
NASA Astrophysics Data System (ADS)
Kies, Alexander; Brown, Tom; Schlachtberger, David; Schramm, Stefan
2017-04-01
The supply-demand imbalance is a major concern in the presence of large shares of highly variable renewable generation from sources like wind and photovoltaics (PV) in power systems. Other than the measures on the generation side, such as flexible backup generation or energy storage, sector coupling or demand side management are the most likely option to counter imbalances, therefore to ease the integration of renewable generation. Demand side management usually refers to load shifting, which comprises the reaction of electricity consumers to price fluctuations. In this work, we derive a novel methodology to model the interplay of load shifting and provided incentives via real-time pricing in highly renewable power systems. We use weather data to simulate generation from the renewable sources of wind and photovoltaics, as well as historical load data, split into different consumption categories, such as, heating, cooling, domestic, etc., to model a simplified power system. Together with renewable power forecast data, a simple market model and approaches to incorporate sector coupling [1] and load shifting [2,3], we model the interplay of incentives and load shifting for different scenarios (e.g., in dependency of the risk-aversion of consumers or the forecast horizon) and demonstrate the practical benefits of load shifting. First, we introduce the novel methodology and compare it with existing approaches. Secondly, we show results of numerical simulations on the effects of load shifting: It supports the integration of PV power by providing a storage, which characteristics can be described as "daily" and provides a significant amount of balancing potential. Lastly, we propose an experimental setup to obtain empirical data on end-consumer load-shifting behaviour in response to price incentives. References [1] Brown, T., Schlachtberger, D., Kies. A., Greiner, M., Sector coupling in a highly renewable European energy system, Proc. of the 15th International Workshop on Large-Scale Integration of Wind Power into Power Systems as well as on Transmission Networks for Offshore Wind Power Plants, Vienna, Austria, 15.-17. November 2016 [2] Kleinhans, D.: Towards a systematic characterization of the potential of demand side management, arXiv preprint arXiv:1401.4121, 2014 [3] Kies, A., Schyska, B. U., von Bremen, L., The Demand Side Management Potential to Balance a Highly Renewable European Power System. Energies, 9(11), 955, 2016
Exploiting variability for energy optimization of parallel programs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lavrijsen, Wim; Iancu, Costin; de Jong, Wibe
2016-04-18
Here in this paper we present optimizations that use DVFS mechanisms to reduce the total energy usage in scientific applications. Our main insight is that noise is intrinsic to large scale parallel executions and it appears whenever shared resources are contended. The presence of noise allows us to identify and manipulate any program regions amenable to DVFS. When compared to previous energy optimizations that make per core decisions using predictions of the running time, our scheme uses a qualitative approach to recognize the signature of executions amenable to DVFS. By recognizing the "shape of variability" we can optimize codes withmore » highly dynamic behavior, which pose challenges to all existing DVFS techniques. We validate our approach using offline and online analyses for one-sided and two-sided communication paradigms. We have applied our methods to NWChem, and we show best case improvements in energy use of 12% at no loss in performance when using online optimizations running on 720 Haswell cores with one-sided communication. With NWChem on MPI two-sided and offline analysis, capturing the initialization, we find energy savings of up to 20%, with less than 1% performance cost.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Canavan, G.H.
Optimizations of missile allocation based on linearized exchange equations produce accurate allocations, but the limits of validity of the linearization are not known. These limits are explored in the context of the upload of weapons by one side to initially small, equal forces of vulnerable and survivable weapons. The analysis compares analytic and numerical optimizations and stability induces based on aggregated interactions of the two missile forces, the first and second strikes they could deliver, and they resulting costs. This note discusses the costs and stability indices induced by unilateral uploading of weapons to an initially symmetrical low force configuration.more » These limits are quantified for forces with a few hundred missiles by comparing analytic and numerical optimizations of first strike costs. For forces of 100 vulnerable and 100 survivable missiles on each side, the analytic optimization agrees closely with the numerical solution. For 200 vulnerable and 200 survivable missiles on each side, the analytic optimization agrees with the induces to within about 10%, but disagrees with the allocation of the side with more weapons by about 50%. The disagreement comes from the interaction of the possession of more weapons with the shift of allocation from missiles to value that they induce.« less
NASA Astrophysics Data System (ADS)
Cui, Gaoying; Fan, Jie; Qin, Yuchen; Wang, Dong; Chen, Guangyan
2017-05-01
In order to promote the effective use of demand response load side resources, promote the interaction between supply and demand, enhance the level of customer service and achieve the overall utilization of energy, this paper briefly explain the background significance of design demand response information platform and current situation of domestic and foreign development; Analyse the new demand of electricity demand response combined with the application of Internet and big data technology; Design demand response information platform architecture, construct demand responsive system, analyse process of demand response strategy formulate and intelligent execution implement; study application which combined with the big data, Internet and demand response technology; Finally, from information interaction architecture, control architecture and function design perspective design implementation of demand response information platform, illustrate the feasibility of the proposed platform design scheme implemented in a certain extent.
Ghosh, A K; Ganguli, S; Bose, K S
1982-12-01
The metabolic demand, using the relationship between speed and energy cost, and the optimal speed of walking, estimated by means of speed and energy cost per unit distance travelled, were studied in 16 post-polio subjects with lower limb affliction and 20 normal subjects with sedentary habits. It was observed that the post-polio subjects consumed higher energy than the normal persons at each walking speed between 0.28 and 1.26 m/s. The optimal speed of walking in post-polio subjects was lower than that of the normal persons and was associated with a higher energy demand per unit distance travelled. It was deduced that the post-polio subjects. not having used any assistive devices for a long time, have acquired severe degrees of disability which not only hindered their normal gait but also demanded extra energy from them.
Riedel, Natalie; Müller, Andreas; Ebener, Melanie
2015-05-01
To investigate whether aging employees' selection, optimization, and compensation (SOC) strategies were associated with work ability over and above job demand and control variables, as well as across professions. Multivariable linear regressions were conducted using a representative sample of German employees born in 1959 and 1965 (N = 6057). SOC was assessed to have an independent effect on work ability. Associations of job demands and control variables with work ability were more prominent. The SOC tended to enhance the positive association between decision authority and work ability. Individual strategies of selection, optimization, and compensation could be considered as psychosocial resources adding up to a better work ability and complement prevention programs. Workplace interventions should deal with job demands and control to maintain older employees' work ability in times of working population shrinkage.
Outsourcing to increase service capacity in a New Zealand hospital.
Renner, C; Palmer, E
1999-01-01
Service firms manage variability using both demand-side tactics (levelling customer demand), and supply-side tactics (increasing available capacity). One popular way of increasing available capacity is the outsourcing of non-core services. This article uses a case study to examine the impact of an outsourced non-core service on a hospital's overall service system. Findings show that the outsourced service provides access to more sophisticated technology, increases in-house capacity and saves capital expenditure. However, the outsourcing also increases the scheduling problems that the hospital faces. These problems are largely due to communication delays from the involvement of more than one organisation. These delays decrease the response time available to match changes in demand for the outsourced service. Given the obvious benefits of such outsourcing, the article concludes that management should pay close attention to the communication pathways between organisations, in order to minimise the end effects identified in this study.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhattarai, Bishnu; Kouzelis, Konstantinos; Mendaza, Iker
The gradual active load penetration in low voltage distribution grids is expected to challenge their network capacity in the near future. Distribution system operators should for this reason resort to either costly grid reinforcements or to demand side management mechanisms. Since demand side management implementation is usually cheaper, it is also the favorable solution. To this end, this article presents a framework for handling grid limit violations, both voltage and current, to ensure a secure and qualitative operation of the distribution grid. This framework consists of two steps, namely a proactive centralized and subsequently a reactive decentralized control scheme. Themore » former is employed to balance the one hour ahead load while the latter aims at regulating the consumption in real-time. In both cases, the importance of fair use of electricity demand flexibility is emphasized. Thus, it is demonstrated that this methodology aids in keeping the grid status within preset limits while utilizing flexibility from all flexibility participants.« less
International experiences of promoting generics use and its implications to China.
Sun, Jing
2013-05-01
To summarize international experiences in promoting use of generics and to extract essence for China's reference. This is a commentary of two systematic reviews about policies to promote use of generics and its implications to China. Price, reimbursement, and generic substitution policies in European countries, and approaches in low and middle income countries in promoting market competition, appropriate intellectual property right protection strategy, and necessary demand side incentives, are all meaningful for China to contain soaring pharmaceutical expenditures, and to maintain the achievements and outcomes of the national health system reform. Effective promotion of generics use must be practice based on the real situation. Tailor-made and comprehensive measures are needed to address both demand and supply sides barriers before achieving tangible cost containment effect without unexpected side effects. © 2013 Wiley Publishing Asia Pty Ltd and Chinese Cochrane Center, West China Hospital of Sichuan University.
Recent Advances in the Recombinant Biosynthesis of Polyphenols
Chouhan, Sonam; Sharma, Kanika; Zha, Jian; Guleria, Sanjay; Koffas, Mattheos A. G.
2017-01-01
Plants are the source of various natural compounds with pharmaceutical and nutraceutical importance which have shown numerous health benefits with relatively fewer side effects. However, extraction of these compounds from native producers cannot meet the ever-increasing demands of the growing population due to, among other things, the limited production of the active compound(s). Their production depends upon the metabolic demands of the plant and is also subjected to environmental conditions, abundance of crop species and seasonal variations. Moreover, their extraction from plants requires complex downstream processing and can also lead to the extinction of many useful plant varieties. Microbial engineering is one of the alternative approaches which can meet the global demand for natural products in an eco-friendly manner. Metabolic engineering of microbes or pathway reconstruction using synthetic biology tools and novel enzymes lead to the generation of a diversity of compounds (like flavonoids, stilbenes, anthocyanins etc.) and their natural and non-natural derivatives. Strain and pathway optimization, pathway regulation and tolerance engineering have produced microbial cell factories into which the metabolic pathway of plants can be introduced for the production of compounds of interest on an industrial scale in an economical and eco-friendly way. While microbial production of phytochemicals needs to further increase product titer if it is ever to become a commercial success. The present review covers the advancements made for the improvement of microbial cell factories in order to increase the product titer of recombinant polyphenolic compounds. PMID:29201020
Optimization of pressure gauge locations for water distribution systems using entropy theory.
Yoo, Do Guen; Chang, Dong Eil; Jun, Hwandon; Kim, Joong Hoon
2012-12-01
It is essential to select the optimal pressure gauge location for effective management and maintenance of water distribution systems. This study proposes an objective and quantified standard for selecting the optimal pressure gauge location by defining the pressure change at other nodes as a result of demand change at a specific node using entropy theory. Two cases are considered in terms of demand change: that in which demand at all nodes shows peak load by using a peak factor and that comprising the demand change of the normal distribution whose average is the base demand. The actual pressure change pattern is determined by using the emitter function of EPANET to reflect the pressure that changes practically at each node. The optimal pressure gauge location is determined by prioritizing the node that processes the largest amount of information it gives to (giving entropy) and receives from (receiving entropy) the whole system according to the entropy standard. The suggested model is applied to one virtual and one real pipe network, and the optimal pressure gauge location combination is calculated by implementing the sensitivity analysis based on the study results. These analysis results support the following two conclusions. Firstly, the installation priority of the pressure gauge in water distribution networks can be determined with a more objective standard through the entropy theory. Secondly, the model can be used as an efficient decision-making guide for gauge installation in water distribution systems.
Valuing physically and financially-induced flexibility in large-scale water resources systems
NASA Astrophysics Data System (ADS)
Tilmant, Amaury; Pina, Jasson; Côté, Pascal
2017-04-01
In a world characterized by rapid changes in terms of water demands and supplies, there is a growing and persistent need for institutional reforms that promote cross-sectoral, adaptive management processes and policies. Yet, in many regions throughout the world, the continued expansion of supply-side infrastructure is still perceived as the way to go despite the rising financial, social and environmental costs. This trend is further compounded by the risks posed by climate change; reservoir storage, for example, is still perceived as a key element of climate change adaptation strategies in many countries. There is a growing concern that such strategies may result in a rigidity trap whereby the physical and institutional infrastructure become inflexible and unable to adapt to changes because they are mutually reinforcing each other. However, several authors have recently advocated for adaptive, flexible, management techniques involving a more diversified portfolio of measures whose management is regularly updated as new information about supplies and demands becomes available. Despite being conceptually attractive, such a management approach presents several challenges to policy makers. One of them is the sheer amount of information that must be processed each time a management decision must be taken. To address this issue, we propose an optimization framework that can be used to determine the optimal management of a large portfolio of physical and financial assets using various hydro-climatic information. This optimization framework is illustrated with the management of a power system in Quebec involving various power stations, reservoirs, power and energy contracts as well as hydrologic and climatic data. The results can be used to assess the economic value of the flexibility induced by either the physical assets (power stations and reservoirs) or by the financial ones (contracts), an information we believe is important to highlight the benefits of adaptive management techniques.
Exploring efficacy of residential energy efficiency programs in Florida
NASA Astrophysics Data System (ADS)
Taylor, Nicholas Wade
Electric utilities, government agencies, and private interests in the U.S. have committed and continue to invest substantial resources in the pursuit of energy efficiency and conservation through demand-side management (DSM) programs. Program investments, and the demand for impact evaluations that accompany them, are projected to grow in coming years due to increased pressure from state-level energy regulation, costs and challenges of building additional production capacity, fuel costs and potential carbon or renewable energy regulation. This dissertation provides detailed analyses of ex-post energy savings from energy efficiency programs in three key sectors of residential buildings: new, single-family, detached homes; retrofits to existing single-family, detached homes; and retrofits to existing multifamily housing units. Each of the energy efficiency programs analyzed resulted in statistically significant energy savings at the full program group level, yet savings for individual participants and participant subgroups were highly variable. Even though savings estimates were statistically greater than zero, those energy savings did not always meet expectations. Results also show that high variability in energy savings among participant groups or subgroups can negatively impact overall program performance and can undermine marketing efforts for future participation. Design, implementation, and continued support of conservation programs based solely on deemed or projected savings is inherently counter to the pursuit of meaningful energy conservation and reductions in greenhouse gas emissions. To fully understand and optimize program impacts, consistent and robust measurement and verification protocols must be instituted in the design phase and maintained over time. Furthermore, marketing for program participation must target those who have the greatest opportunity for savings. In most utility territories it is not possible to gain access to the type of large scale datasets that would facilitate robust program analysis. Along with measuring and optimizing energy conservation programs, utilities should provide public access to historical consumption data. Open access to data, program optimization, consistent measurement and verification and transparency in reported savings are essential to reducing energy use and its associated environmental impacts.
The Supply and Demand of Accounting Faculty by Interest Area.
ERIC Educational Resources Information Center
Norris, Daniel
1991-01-01
Position advertisements in "The Accounting Review" and data on numbers of doctoral accounting faculty are used to assess the accounting job market, by interest area, over the past decade. Determines that current trends in the demand side are expected to continue, with auditing and systems the "hot" areas. (Author/JOW)
Health consumers and stem cell therapy innovation: markets, models and regulation.
Salter, Brian; Zhou, Yinhua; Datta, Saheli
2014-05-01
Global health consumer demand for stem cell therapies is vibrant, but the supply of treatments from the conventional science-based model of innovation is small and unlikely to increase in the near future. At the same time, several models of medical innovation have emerged that can respond to the demand, often employing a transnational value chain to deliver the product. Much of the commentary has approached the issue from a supply side perspective, demonstrating the extent to which national and transnational regulation fails to impose what are regarded as appropriate standards on the 'illicit' supply of stem cell therapies characterized by little data and poor outcomes. By contrast, this article presents a political economic analysis with a strong demand side perspective, arguing that the problem of what is termed 'stem cell tourism' is embedded in the demand-supply relationship of the health consumer market and its engagement with different types of stem cell therapy innovation. To be meaningful, discussions of regulation must recognize that analysis or risk being sidelined by a market, which ignores their often wishful thinking.
Route Monopolie and Optimal Nonlinear Pricing
NASA Technical Reports Server (NTRS)
Tournut, Jacques
2003-01-01
To cope with air traffic growth and congested airports, two solutions are apparent on the supply side: 1) use larger aircraft in the hub and spoke system; or 2) develop new routes through secondary airports. An enlarged route system through secondary airports may increase the proportion of route monopolies in the air transport market.The monopoly optimal non linear pricing policy is well known in the case of one dimension (one instrument, one characteristic) but not in the case of several dimensions. This paper explores the robustness of the one dimensional screening model with respect to increasing the number of instruments and the number of characteristics. The objective of this paper is then to link and fill the gap in both literatures. One of the merits of the screening model has been to show that a great varieD" of economic questions (non linear pricing, product line choice, auction design, income taxation, regulation...) could be handled within the same framework.VCe study a case of non linear pricing (2 instruments (2 routes on which the airline pro_ddes customers with services), 2 characteristics (demand of services on these routes) and two values per characteristic (low and high demand of services on these routes)) and we show that none of the conclusions of the one dimensional analysis remain valid. In particular, upward incentive compatibility constraint may be binding at the optimum. As a consequence, they may be distortion at the top of the distribution. In addition to this, we show that the optimal solution often requires a kind of form of bundling, we explain explicitly distortions and show that it is sometimes optimal for the monopolist to only produce one good (instead of two) or to exclude some buyers from the market. Actually, this means that the monopolist cannot fully apply his monopoly power and is better off selling both goods independently.We then define all the possible solutions in the case of a quadratic cost function for a uniform distribution of agent types and explain the implications for airlines in terms of service differentiation.
M-Learning Adoption: A Perspective from a Developing Country
ERIC Educational Resources Information Center
Iqbal, Shakeel; Qureshi, Ijaz A.
2012-01-01
M-learning is the style of learning for the new millennium. Decreases in cost and increases in capabilities of mobile devices have made this medium attractive for the dissemination of knowledge. Mobile engineers, software developers, and educationists represent the supply side of this technology, whereas students represent the demand side. In…
ERIC Educational Resources Information Center
Tooley, James; Dixon, Pauline
2006-01-01
Three types of privatisation are identified--involving demand-side financing, reforms to the educational supply-side and "de facto" privatisation, where responsibilities are transferred to the private sector, through the rapid growth of private schools, rather than through reform or legislation. Although "de facto"…
Institutional Diversity in Russian Higher Education: Revolutions and Evolution
ERIC Educational Resources Information Center
Froumin, Isak; Kouzminov, Yaroslav; Semyonov, Dmitry
2014-01-01
This paper is devoted to changes in the structure of the higher education system in Russia, analysing both historical context and current institutional diversity. The review starts from the Soviet quasi-corporate system when the state combined demand-side and supply-side roles in higher education. The post-Soviet transformation brings new forces…
Li, Zukui; Ding, Ran; Floudas, Christodoulos A.
2011-01-01
Robust counterpart optimization techniques for linear optimization and mixed integer linear optimization problems are studied in this paper. Different uncertainty sets, including those studied in literature (i.e., interval set; combined interval and ellipsoidal set; combined interval and polyhedral set) and new ones (i.e., adjustable box; pure ellipsoidal; pure polyhedral; combined interval, ellipsoidal, and polyhedral set) are studied in this work and their geometric relationship is discussed. For uncertainty in the left hand side, right hand side, and objective function of the optimization problems, robust counterpart optimization formulations induced by those different uncertainty sets are derived. Numerical studies are performed to compare the solutions of the robust counterpart optimization models and applications in refinery production planning and batch process scheduling problem are presented. PMID:21935263
Schumann, Marcel; Armen, Roger S
2013-05-30
Molecular docking of small-molecules is an important procedure for computer-aided drug design. Modeling receptor side chain flexibility is often important or even crucial, as it allows the receptor to adopt new conformations as induced by ligand binding. However, the accurate and efficient incorporation of receptor side chain flexibility has proven to be a challenge due to the huge computational complexity required to adequately address this problem. Here we describe a new docking approach with a very fast, graph-based optimization algorithm for assignment of the near-optimal set of residue rotamers. We extensively validate our approach using the 40 DUD target benchmarks commonly used to assess virtual screening performance and demonstrate a large improvement using the developed side chain optimization over rigid receptor docking (average ROC AUC of 0.693 vs. 0.623). Compared to numerous benchmarks, the overall performance is better than nearly all other commonly used procedures. Furthermore, we provide a detailed analysis of the level of receptor flexibility observed in docking results for different classes of residues and elucidate potential avenues for further improvement. Copyright © 2013 Wiley Periodicals, Inc.
Richard, Lauralie; Furler, John; Densley, Konstancja; Haggerty, Jeannie; Russell, Grant; Levesque, Jean-Frederic; Gunn, Jane
2016-04-12
Improving access to primary healthcare (PHC) for vulnerable populations is important for achieving health equity, yet this remains challenging. Evidence of effective interventions is rather limited and fragmented. We need to identify innovative ways to improve access to PHC for vulnerable populations, and to clarify which elements of health systems, organisations or services (supply-side dimensions of access) and abilities of patients or populations (demand-side dimensions of access) need to be strengthened to achieve transformative change. The work reported here was conducted as part of IMPACT (Innovative Models Promoting Access-to-Care Transformation), a 5-year Canadian-Australian research program aiming to identify, implement and trial best practice interventions to improve access to PHC for vulnerable populations. We undertook an environmental scan as a broad screening approach to identify the breadth of current innovations from the field. We distributed a brief online survey to an international audience of PHC researchers, practitioners, policy makers and stakeholders using a combined email and social media approach. Respondents were invited to describe a program, service, approach or model of care that they considered innovative in helping vulnerable populations to get access to PHC. We used descriptive statistics to characterise the innovations and conducted a qualitative framework analysis to further examine the text describing each innovation. Seven hundred forty-four responses were recorded over a 6-week period. 240 unique examples of innovations originating from 14 countries were described, the majority from Canada and Australia. Most interventions targeted a diversity of population groups, were government funded and delivered in a community health, General Practice or outreach clinic setting. Interventions were mainly focused on the health sector and directed at organisational and/or system level determinants of access (supply-side). Few innovations were developed to enhance patients' or populations' abilities to access services (demand-side), and rarely did initiatives target both supply- and demand-side determinants of access. A wide range of innovations improving access to PHC were identified. The access framework was useful in uncovering the disparity between supply- and demand-side dimensions and pinpointing areas which could benefit from further attention to close the equity gap for vulnerable populations in accessing PHC services that correspond to their needs.
Gabbett, Tim J; Abernethy, Bruce; Jenkins, David G
2012-02-01
The purpose of this study was to investigate the effect of changes in field size on the physiological and skill demands of small-sided games in elite junior and senior rugby league players. Sixteen elite senior rugby league players ([mean ± SE] age, 23.6 ± 0.5 years) and 16 elite junior rugby league players ([mean ± SE] age, 17.3 ± 0.3 years) participated in this study. On day 1, 2 teams played an 8-minute small-sided game on a small field (10-m width × 40-m length), whereas the remaining 2 teams played the small-sided game on a larger sized field (40-m width × 70-m length). On day 2, the groups were crossed over. Movement was recorded by a global positioning system unit sampling at 5 Hz. Games were filmed to count the number of possessions and the number and quality of disposals. The games played on a larger field resulted in a greater (p < 0.05) total distance covered, and distances covered in moderate, high, and very-high velocity movement intensities. Senior players covered more distance at moderate, high, and very-high intensities, and less distance at low and very-low intensities during small-sided games than junior players. Although increasing field size had no significant influence (p > 0.05) over the duration of recovery periods for junior players, larger field size significantly reduced (p < 0.05) the amount of short-, moderate-, and long-duration recovery periods in senior players. No significant between-group differences (p > 0.05) were detected for games played on a small or large field for the number or quality of skill involvements. These results suggest that increases in field size serve to increase the physiological demands of small-sided games but have minimal influence over the volume or quality of skill executions in elite rugby league players.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-24
... Intelligent Network Flow Optimization Operational Concepts; Notice of Public Meeting AGENCY: Research and... Demand Management (ADTM) and Intelligent Network Flow Optimization (INFLO) operational concepts. The ADTM... February 8, 2012, 8:30 to 4:30 p.m. The location for both meetings is the Hall of States, 444 North Capitol...
Gopalan, Saji S; Durairaj, Varatharajan
2015-03-01
Given the increasing need for mainstreaming household financing for women's nonmaternal health care and evidences on community-based financing's contribution to women's health care in general, this study explored their scope for nonmaternal health care in Orissa. A qualitative assessment conducted focus group discussions with rural women who met the eligibility criteria. Community-based financing provided financial access and risk protection for women's nonmaternal health care during the previous 1 year, though not adequately. Schemes covering outpatient care (or mild illnesses) provided relatively more financial access. The major determinants of their restricted financial access were limited sum assured, noncomprehensive coverage of services, exclusion of elderly women, and the lower priority households gave to nonmaternal health care. Community-based financing requires relevant structural changes along with demand-side behavioral modifications to ensure optimal attention to women's nonmaternal health care. © 2012 APJPH.
Automatic control of electric thermal storage (heat) under real-time pricing. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daryanian, B.; Tabors, R.D.; Bohn, R.E.
1995-01-01
Real-time pricing (RTP) can be used by electric utilities as a control signal for responsive demand-side management (DSM) programs. Electric thermal storage (ETS) systems in buildings provide the inherent flexibility needed to take advantage of variations in prices. Under RTP, optimal performance for ETS operations is achieved under market conditions where reductions in customers` costs coincide with the lowering of the cost of service for electric utilities. The RTP signal conveys the time-varying actual marginal cost of the electric service to customers. The RTP rate is a combination of various cost components, including marginal generation fuel and maintenance costs, marginalmore » costs of transmission and distribution losses, and marginal quality of supply and transmission costs. This report describes the results of an experiment in automatic control of heat storage systems under RTP during the winter seasons of 1989--90 and 1990--91.« less
Pricing policy for declining demand using item preservation technology.
Khedlekar, Uttam Kumar; Shukla, Diwakar; Namdeo, Anubhav
2016-01-01
We have designed an inventory model for seasonal products in which deterioration can be controlled by item preservation technology investment. Demand for the product is considered price sensitive and decreases linearly. This study has shown that the profit is a concave function of optimal selling price, replenishment time and preservation cost parameter. We simultaneously determined the optimal selling price of the product, the replenishment cycle and the cost of item preservation technology. Additionally, this study has shown that there exists an optimal selling price and optimal preservation investment to maximize the profit for every business set-up. Finally, the model is illustrated by numerical examples and sensitive analysis of the optimal solution with respect to major parameters.
Auto-DR and Pre-cooling of Buildings at Tri-City Corporate Center
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yin, Rongxin; Xu, Peng; Kiliccote, Sila
2008-11-01
Over the several past years, Lawrence Berkeley National Laboratory (LBNL) has conducted field tests for different pre-cooling strategies in different commercial buildings within California. The test results indicated that pre-cooling strategies were effective in reducing electric demand in these buildings during peak periods. This project studied how to optimize pre-cooling strategies for eleven buildings in the Tri-City Corporate Center, San Bernardino, California with the assistance of a building energy simulation tool -- the Demand Response Quick Assessment Tool (DRQAT) developed by LBNL's Demand Response Research Center funded by the California Energy Commission's Public Interest Energy Research (PIER) Program. From themore » simulation results of these eleven buildings, optimal pre-cooling and temperature reset strategies were developed. The study shows that after refining and calibrating initial models with measured data, the accuracy of the models can be greatly improved and the models can be used to predict load reductions for automated demand response (Auto-DR) events. This study summarizes the optimization experience of the procedure to develop and calibrate building models in DRQAT. In order to confirm the actual effect of demand response strategies, the simulation results were compared to the field test data. The results indicated that the optimal demand response strategies worked well for all buildings in the Tri-City Corporate Center. This study also compares DRQAT with other building energy simulation tools (eQUEST and BEST). The comparison indicate that eQUEST and BEST underestimate the actual demand shed of the pre-cooling strategies due to a flaw in DOE2's simulation engine for treating wall thermal mass. DRQAT is a more accurate tool in predicting thermal mass effects of DR events.« less
Assessment of the Electrification of the Road Transport Sector on Net System Emissions
NASA Astrophysics Data System (ADS)
Miller, James
As worldwide environmental consciousness grows, electric vehicles (EVs) are becoming more common and despite the incredible potential for emissions reduction, the net emissions of the power system supply side plus the transportation system are dependent on the generation matrix. Current EV charging patterns tend to correspond directly with the peak consumption hours and have the potential to increase demand sharply allowing for only a small penetration of Electric Vehicles. Using the National Household Travel Survey (NHTS) data a model is created for vehicle travel patterns using trip chaining. Charging schemes are modeled to include uncontrolled residential, uncontrolled residential/industrial charging, optimized charging and optimized charging with vehicle to grid discharging. A charging profile is then determined based upon the assumption that electric vehicles would directly replace a percentage of standard petroleum-fueled vehicles in a known system. Using the generation profile for the specified region, a unit commitment model is created to establish not only the generation dispatch, but also the net CO2 profile for variable EV penetrations and charging profiles. This model is then used to assess the impact of the electrification of the road transport sector on the system net emissions.
Yang, Hui; Zhang, Jie; Ji, Yuefeng; Tan, Yuanlong; Lin, Yi; Han, Jianrui; Lee, Young
2015-09-07
Data center interconnection with elastic optical network is a promising scenario to meet the high burstiness and high-bandwidth requirements of data center services. In our previous work, we implemented cross stratum optimization of optical network and application stratums resources that allows to accommodate data center services. In view of this, this study extends the data center resources to user side to enhance the end-to-end quality of service. We propose a novel data center service localization (DCSL) architecture based on virtual resource migration in software defined elastic data center optical network. A migration evaluation scheme (MES) is introduced for DCSL based on the proposed architecture. The DCSL can enhance the responsiveness to the dynamic end-to-end data center demands, and effectively reduce the blocking probability to globally optimize optical network and application resources. The overall feasibility and efficiency of the proposed architecture are experimentally verified on the control plane of our OpenFlow-based enhanced SDN testbed. The performance of MES scheme under heavy traffic load scenario is also quantitatively evaluated based on DCSL architecture in terms of path blocking probability, provisioning latency and resource utilization, compared with other provisioning scheme.
Food security and sustainable intensification.
Godfray, H Charles J; Garnett, Tara
2014-04-05
The coming decades are likely to see increasing pressures on the global food system, both on the demand side from increasing population and per capita consumption, and on the supply side from greater competition for inputs and from climate change. This paper argues that the magnitude of the challenge is such that action is needed throughout the food system, on moderating demand, reducing waste, improving governance and producing more food. It discusses in detail the last component, arguing that more food should be produced using sustainable intensification (SI) strategies, and explores the rationale behind, and meaning of, this term. It also investigates how SI may interact with other food policy agendas, in particular, land use and biodiversity, animal welfare and human nutrition.
Adaptive heat pump and battery storage demand side energy management
NASA Astrophysics Data System (ADS)
Sobieczky, Florian; Lettner, Christian; Natschläger, Thomas; Traxler, Patrick
2017-11-01
An adaptive linear model predictive control strategy is introduced for the problem of demand side energy management, involving a photovoltaic device, a battery, and a heat pump. Moreover, the heating influence of solar radiation via the glass house effect is considered. Global sunlight radiation intensity and the outside temperature are updated by weather forecast data. The identification is carried out after adapting to a time frame witch sufficiently homogeneous weather. In this way, in spite of the linearity an increase in precision and cost reduction of up to 46% is achieved. It is validated for an open and closed loop version of the MPC problem using real data of the ambient temperature and the global radiation.
Integrated power sector efficiency analysis: A case study of Costa Rica
DOE Office of Scientific and Technical Information (OSTI.GOV)
Waddle, D.B.; MacDonald, J.M.
1990-03-01
In an effort to analyze and document the potential for power sector efficiency improvements from generation to end-use, the Agency for International Development and the Government of Costa Rica are jointly conducting an integrated power sector efficiency analysis. Potential for energy and cost savings in power plants, transmission and distribution, and demand-side management programs are being evaluated. The product of this study will be an integrated investment plan for the Instituto Costarricense de Electricidad, incorporating both supply and demand side investment options. This paper presents the methodology employed in the study, as well as preliminary estimates of the results ofmore » the study. 14 refs., 2 figs., 5 tabs.« less
Optimization Based Data Mining Approah for Forecasting Real-Time Energy Demand
DOE Office of Scientific and Technical Information (OSTI.GOV)
Omitaomu, Olufemi A; Li, Xueping; Zhou, Shengchao
The worldwide concern over environmental degradation, increasing pressure on electric utility companies to meet peak energy demand, and the requirement to avoid purchasing power from the real-time energy market are motivating the utility companies to explore new approaches for forecasting energy demand. Until now, most approaches for forecasting energy demand rely on monthly electrical consumption data. The emergence of smart meters data is changing the data space for electric utility companies, and creating opportunities for utility companies to collect and analyze energy consumption data at a much finer temporal resolution of at least 15-minutes interval. While the data granularity providedmore » by smart meters is important, there are still other challenges in forecasting energy demand; these challenges include lack of information about appliances usage and occupants behavior. Consequently, in this paper, we develop an optimization based data mining approach for forecasting real-time energy demand using smart meters data. The objective of our approach is to develop a robust estimation of energy demand without access to these other building and behavior data. Specifically, the forecasting problem is formulated as a quadratic programming problem and solved using the so-called support vector machine (SVM) technique in an online setting. The parameters of the SVM technique are optimized using simulated annealing approach. The proposed approach is applied to hourly smart meters data for several residential customers over several days.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broeer, Torsten; Fuller, Jason C.; Tuffner, Francis K.
2014-01-31
Electricity generation from wind power and other renewable energy sources is increasing, and their variability introduces new challenges to the power system. The emergence of smart grid technologies in recent years has seen a paradigm shift in redefining the electrical system of the future, in which controlled response of the demand side is used to balance fluctuations and intermittencies from the generation side. This paper presents a modeling framework for an integrated electricity system where loads become an additional resource. The agent-based model represents a smart grid power system integrating generators, transmission, distribution, loads and market. The model incorporates generatormore » and load controllers, allowing suppliers and demanders to bid into a Real-Time Pricing (RTP) electricity market. The modeling framework is applied to represent a physical demonstration project conducted on the Olympic Peninsula, Washington, USA, and validation simulations are performed using actual dynamic data. Wind power is then introduced into the power generation mix illustrating the potential of demand response to mitigate the impact of wind power variability, primarily through thermostatically controlled loads. The results also indicate that effective implementation of Demand Response (DR) to assist integration of variable renewable energy resources requires a diversity of loads to ensure functionality of the overall system.« less
NASA Astrophysics Data System (ADS)
Davendralingam, Navindran
Conceptual design of aircraft and the airline network (routes) on which aircraft fly on are inextricably linked to passenger driven demand. Many factors influence passenger demand for various Origin-Destination (O-D) city pairs including demographics, geographic location, seasonality, socio-economic factors and naturally, the operations of directly competing airlines. The expansion of airline operations involves the identificaion of appropriate aircraft to meet projected future demand. The decisions made in incorporating and subsequently allocating these new aircraft to serve air travel demand affects the inherent risk and profit potential as predicted through the airline revenue management systems. Competition between airlines then translates to latent passenger observations of the routes served between OD pairs and ticket pricing---this in effect reflexively drives future states of demand. This thesis addresses the integrated nature of aircraft design, airline operations and passenger demand, in order to maximize future expected profits as new aircraft are brought into service. The goal of this research is to develop an approach that utilizes aircraft design, airline network design and passenger demand as a unified framework to provide better integrated design solutions in order to maximize expexted profits of an airline. This is investigated through two approaches. The first is a static model that poses the concurrent engineering paradigm above as an investment portfolio problem. Modern financial portfolio optimization techniques are used to leverage risk of serving future projected demand using a 'yet to be introduced' aircraft against potentially generated future profits. Robust optimization methodologies are incorporated to mitigate model sensitivity and address estimation risks associated with such optimization techniques. The second extends the portfolio approach to include dynamic effects of an airline's operations. A dynamic programming approach is employed to simulate the reflexive nature of airline supply-demand interactions by modeling the aggregate changes in demand that would result from tactical allocations of aircraft to maximize profit. The best yet-to-be-introduced aircraft maximizes profit by minimizing the long term fleetwide direct operating costs.
Vizcaíno Revés, Núria; Stahl, Cristina; Stoffel, Michael; Bali, Monty; Forterre, Franck
2013-10-01
To describe the most reliable insertion angle, corridor length and width to place a ventral transarticular atlantoaxial screw in miniature breed dogs. Retrospective CT imaging study. Cervical CT scans of toy breed dogs (n = 21). Dogs were divided into 2 groups--group 1: no atlantoaxial abnormalities; group 2: atlantoaxial instability. Insertion angle in medial to lateral and ventral to dorsal direction was measured in group 1. Corridor length and width were measured in groups 1 and 2. Corridor width was measured at 3 points of the corridor. Each variable was measured 3 times and the mean used for statistical analysis. Mean ± SD optimal transarticular atlantoaxial insertion angle was determined to be 40 ± 1° in medial to lateral direction from the midline and 20 ± 1° in ventral to dorsal direction from the floor of the neural canal of C2. Mean corridor length was 7 mm (range, 4.5-8.0 mm). Significant correlation was found between corridor length, body weight, and age. Mean bone corridor width ranged from 3 to 5 mm. Statistically significant differences were found between individuals, gender and measured side. Optimal placement of a transarticular screw for atlantoaxial joint stabilization is very demanding because the screw path corridor is very narrow. © Copyright 2013 by The American College of Veterinary Surgeons.
Performance of fasteners in wood flour-thermoplastic composite panels
Robert H. Falk; Daniel J. Vos; Steven M. Cramer; Brent W. English
2001-01-01
In the building community, there is a growing demand for high-performance, low-maintenance, and low-cost building products. To meet this demand, natural fiberthermoplastic composites are being used to produce such products as decking, window and door elements, panels, roofing, and siding. In spite of the rapid growth in the use of these composites, little is known...
High Expectations--High Achievement on Literacy: "What Shall We Do in This Hangman's Hour?"
ERIC Educational Resources Information Center
Linnakyla, Pirjo
Finland is a country of great expectations on literacy and literacy education. High expectations and demands have, however, a darker side. High expectations of society, parents, and teachers may have an effect on the students' self-esteem. The economic recession in the early 1990s strongly accelerated the change in literacy demands and…
Education: A Solution for Rural Poverty? Staff Paper 350.
ERIC Educational Resources Information Center
Clouser, Rodney L.
This paper presents an overview of poverty in rural America, and examines the ways in which improved education could alleviate rural poverty. The question of education as a mechanism to reduce poverty includes issues of economic demand and supply. On the demand side, labor market projections indicate that the service sector will continue to grow,…
Rear-side picosecond laser ablation of indium tin oxide micro-grooves
NASA Astrophysics Data System (ADS)
Liu, Peng; Wang, Wenjun; Mei, Xuesong; Liu, Bin; Zhao, Wanqin
2015-06-01
A comparative study of the fabrication of micro-grooves in indium tin oxide films by picosecond laser ablation for application in thin film solar cells is presented, evaluating the variation of different process parameters. Compared with traditional front-side ablation, rear-side ablation results in thinner grooves with varying laser power at a certain scan speed. In particular, and in contrast to front-side ablation, the width of the micro-grooves remains unchanged when the scan speed was changed. Thus, the micro-groove quality can be optimized by adjusting the scan speed while the groove width would not be affected. Furthermore, high-quality micro-grooves with ripple free surfaces and steep sidewalls could only be achieved when applying rear-side ablation. Finally, the formation mechanism of micro-cracks on the groove rims during rear-side ablation is analyzed and the cracks can be almost entirely eliminated by an optimization of the scan speed.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-12
... the carbon emissions of its generating system and take advantage of lower carbon dioxide-emitting.... The SEIS will include examination of a range of supply-side and demand- side management options for... both the scope of alternatives and environmental issues that should be addressed as part of the SEIS...
Residents and urban greenways: Modeling support for the Atlanta BeltLine
Nathan P. Palardy; B. Bynum Boley; Cassandra Johnson Gaither
2018-01-01
Urban greenways have received significant attention due to their many publicized benefits and costs that make them contentious recreational developments. Most prior studies have approached urban greenways from a demand-side perspective solely focused on their users. This study adds to the literature by taking a supply-side approach to assessing resident attitudes...
ERIC Educational Resources Information Center
Patrinos, Harry Anthony; Ariasingam, David Lakshmanan
Central government's supply-side expansions of schooling have not equally benefited all members of society, especially girls, indigenous peoples, tribal groups, disadvantaged minorities, and the poor. Public spending on education is often inefficient, higher education is subsidized at primary education's expense, and costs are becoming…
Disadvantaged Young People Accessing the New Urban Economies of the Post-Industrial City
ERIC Educational Resources Information Center
Raffo, Carlo
2006-01-01
The aim of the paper is to examine current and evolving supply side transition policy initiatives in the light of (a) particular demand side needs of urban young people classified as those most disadvantaged and potentially marginalized; and (b) the emerging realities of accessing and operating within particular examples of high value-added…
NASA Astrophysics Data System (ADS)
Krugon, Seelam; Nagaraju, Dega
2017-05-01
This work describes and proposes an two echelon inventory system under supply chain, where the manufacturer offers credit period to the retailer with exponential price dependent demand. The model is framed as demand is expressed as exponential function of retailer’s unit selling price. Mathematical model is framed to demonstrate the optimality of cycle time, retailer replenishment quantity, number of shipments, and total relevant cost of the supply chain. The major objective of the paper is to provide trade credit concept from the manufacturer to the retailer with exponential price dependent demand. The retailer would like to delay the payments of the manufacturer. At the first stage retailer and manufacturer expressions are expressed with the functions of ordering cost, carrying cost, transportation cost. In second stage combining of the manufacturer and retailer expressions are expressed. A MATLAB program is written to derive the optimality of cycle time, retailer replenishment quantity, number of shipments, and total relevant cost of the supply chain. From the optimality criteria derived managerial insights can be made. From the research findings, it is evident that the total cost of the supply chain is decreased with the increase in credit period under exponential price dependent demand. To analyse the influence of the model parameters, parametric analysis is also done by taking with help of numerical example.
Flexible Demand Management under Time-Varying Prices
NASA Astrophysics Data System (ADS)
Liang, Yong
In this dissertation, the problem of flexible demand management under time-varying prices is studied. This generic problem has many applications, which usually have multiple periods in which decisions on satisfying demand need to be made, and prices in these periods are time-varying. Examples of such applications include multi-period procurement problem, operating room scheduling, and user-end demand scheduling in the Smart Grid, where the last application is used as the main motivating story throughout the dissertation. The current grid is experiencing an upgrade with lots of new designs. What is of particular interest is the idea of passing time-varying prices that reflect electricity market conditions to end users as incentives for load shifting. One key component, consequently, is the demand management system at the user-end. The objective of the system is to find the optimal trade-off between cost saving and discomfort increment resulted from load shifting. In this dissertation, we approach this problem from the following aspects: (1) construct a generic model, solve for Pareto optimal solutions, and analyze the robust solution that optimizes the worst-case payoffs, (2) extend to a distribution-free model for multiple types of demand (appliances), for which an approximate dynamic programming (ADP) approach is developed, and (3) design other efficient algorithms for practical purposes of the flexible demand management system. We first construct a novel multi-objective flexible demand management model, in which there are a finite number of periods with time-varying prices, and demand arrives in each period. In each period, the decision maker chooses to either satisfy or defer outstanding demand to minimize costs and discomfort over a certain number of periods. We consider both the deterministic model, models with stochastic demand or prices, and when only partial information about the stochastic demand or prices is known. We first analyze the stochastic optimization problem when the objective is to minimize the expected total cost and discomfort, then since the decision maker is likely to be risk-averse, and she wants to protect herself from price spikes, we study the robust optimization problem to address the risk-aversion of the decision maker. We conduct numerical studies to evaluate the price of robustness. Next, we present a detailed model that manages multiple types of flexible demand in the absence of knowledge regarding the distributions of related stochastic processes. Specifically, we consider the case in which time-varying prices with general structures are offered to users, and an energy management system for each household makes optimal energy usage, storage, and trading decisions according to the preferences of users. Because of the uncertainties associated with electricity prices, local generation, and the arrival processes of demand, we formulate a stochastic dynamic programming model, and outline a novel and tractable ADP approach to overcome the curses of dimensionality. Then, we perform numerical studies, whose results demonstrate the effectiveness of the ADP approach. At last, we propose another approximation approach based on Q-learning. In addition, we also develop another decentralization-based heuristic. Both the Q-learning approach and the heuristic make necessary assumptions on the knowledge of information, and each of them has unique advantages. We conduct numerical studies on a testing problem. The simulation results show that both the Q-learning and the decentralization based heuristic approaches work well. Lastly, we conclude the paper with some discussions on future extension directions.
NASA Astrophysics Data System (ADS)
Hooda, Nikhil; Damani, Om
2017-06-01
The classic problem of the capital cost optimization of branched piped networks consists of choosing pipe diameters for each pipe in the network from a discrete set of commercially available pipe diameters. Each pipe in the network can consist of multiple segments of differing diameters. Water networks also consist of intermediate tanks that act as buffers between incoming flow from the primary source and the outgoing flow to the demand nodes. The network from the primary source to the tanks is called the primary network, and the network from the tanks to the demand nodes is called the secondary network. During the design stage, the primary and secondary networks are optimized separately, with the tanks acting as demand nodes for the primary network. Typically the choice of tank locations, their elevations, and the set of demand nodes to be served by different tanks is manually made in an ad hoc fashion before any optimization is done. It is desirable therefore to include this tank configuration choice in the cost optimization process itself. In this work, we explain why the choice of tank configuration is important to the design of a network and describe an integer linear program model that integrates the tank configuration to the standard pipe diameter selection problem. In order to aid the designers of piped-water networks, the improved cost optimization formulation is incorporated into our existing network design system called JalTantra.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piette, Mary Ann
California needs new, responsive, demand-side energy technologies to ensure that periods of tight electricity supply on the grid don't turn into power outages. Led by Berkeley Lab's Mary Ann Piette, the California Energy Commission (through its Public Interest Energy Research Program) has established a Demand Response Research Center that addresses two motivations for adopting demand responsiveness: reducing average electricity prices and preventing future electricity crises. The research seeks to understand factors that influence "what works" in Demand Response. Piette's team is investigating the two types of demand response, load response and price response, that may influence and reduce the usemore » of peak electric power through automated controls, peak pricing, advanced communications, and other strategies.« less
Saving Power at Peak Hours (LBNL Science at the Theater)
Piette, Mary Ann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2018-05-23
California needs new, responsive, demand-side energy technologies to ensure that periods of tight electricity supply on the grid don't turn into power outages. Led by Berkeley Lab's Mary Ann Piette, the California Energy Commission (through its Public Interest Energy Research Program) has established a Demand Response Research Center that addresses two motivations for adopting demand responsiveness: reducing average electricity prices and preventing future electricity crises. The research seeks to understand factors that influence "what works" in Demand Response. Piette's team is investigating the two types of demand response, load response and price response, that may influence and reduce the use of peak electric power through automated controls, peak pricing, advanced communications, and other strategies.
NASA Astrophysics Data System (ADS)
Kurdhi, N. A.; Jamaluddin, A.; Jauhari, W. A.; Saputro, D. R. S.
2017-06-01
In this study, we consider a stochastic integrated manufacturer-retailer inventory model with service level constraint. The model analyzed in this article considers the situation in which the vendor and the buyer establish a long-term contract and strategic partnership to jointly determine the best strategy. The lead time and setup cost are assumed can be controlled by an additional crashing cost and an investment, respectively. It is assumed that shortages are allowed and partially backlogged on the buyer’s side, and that the protection interval (i.e., review period plus lead time) demand distribution is unknown but has given finite first and second moments. The objective is to apply the minmax distribution free approach to simultaneously optimize the review period, the lead time, the setup cost, the safety factor, and the number of deliveries in order to minimize the joint total expected annual cost. The service level constraint guarantees that the service level requirement can be satisfied at the worst case. By constructing Lagrange function, the analysis regarding the solution procedure is conducted, and a solution algorithm is then developed. Moreover, a numerical example and sensitivity analysis are given to illustrate the proposed model and to provide some observations and managerial implications.
NASA Astrophysics Data System (ADS)
Xiang, Yu; Tao, Cheng
2018-05-01
During the operation of the personal rapid transit system(PRT), the empty vehicle resources is distributed unevenly because of different passenger demand. In order to maintain the balance between supply and demand, and to meet the passenger needs of the ride, PRT empty vehicle resource allocation model is constructed based on the future demand forecasted by historical demand in this paper. The improved genetic algorithm is implied in distribution of the empty vehicle which can reduce the customers waiting time and improve the operation efficiency of the PRT system so that all passengers can take the PRT vehicles in the shortest time. The experimental result shows that the improved genetic algorithm can allocate the empty vehicle from the system level optimally, and realize the distribution of the empty vehicle resources reasonably in the system.
A Human-Centered Smart Home System with Wearable-Sensor Behavior Analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ji, Jianting; Liu, Ting; Shen, Chao
Smart home has recently attracted much research interest owing to its potential in improving the quality of human life. How to obtain user's demand is the most important and challenging task for appliance optimal scheduling in smart home, since it is highly related to user's unpredictable behavior. In this paper, a human-centered smart home system is proposed to identify user behavior, predict their demand and schedule the household appliances. Firstly, the sensor data from user's wearable devices are monitored to profile user's full-day behavior. Then, the appliance-demand matrix is constructed to predict user's demand on home environment, which is extractedmore » from the history of appliance load data and user behavior. Two simulations are designed to demonstrate user behavior identification, appliance-demand matrix construction and strategy of appliance optimal scheduling generation.« less
NASA Astrophysics Data System (ADS)
Azmeri, Hadihardaja, Iwan K.; Shaskia, Nina; Admaja, Kamal Surya
2017-11-01
Rukoh Reservoir's construction was planned to be built in Krueng Rukoh Watershed with supplet ion from Krueng Tiro River. Rukoh Reservoir operating system as a multipurpose reservoir raised potential conflict of interest between raw water and irrigation water. In this study, the operating system of Rukoh Reservoirs was designed to supply raw water in Titeu Sub-District and replenish water shortage in Baro Irrigation Area which is not able to be served by the Keumala Weir. Reservoir operating system should be planned optimally so that utilization of water in accordance with service area demands. Reservoir operation method was analyzed by using optimization technique with nonlinear programming. Optimization of reservoir operation is intended to minimize potential conflicts of interest in the operation. Suppletion discharge from Krueng Tiro River amounted to 46.62%, which was calculated based on ratio of Baro and Tiro irrigation area. However, during dry seasons, water demands could not be fully met, so there was a shortage of water. By considering the rules to minimize potential conflicts of interest between raw water and irrigation water, it would require suppletion from Krueng Tiro amounted to 52.30%. The increment of suppletion volume could minimize conflicts of interest. It produced l00% reservoir reliability for raw water and irrigation demands. Rukoh reservoir could serve raw water demands of Titeu Sub-District and irrigation demands of Baro irrigation area which is covering an area of 6,047 hectars. Reservoir operation guidelines can specify reservoir water release to balance the demands and the target storage.
Hu, Yu-Chen
2018-01-01
The emergence of smart Internet of Things (IoT) devices has highly favored the realization of smart homes in a down-stream sector of a smart grid. The underlying objective of Demand Response (DR) schemes is to actively engage customers to modify their energy consumption on domestic appliances in response to pricing signals. Domestic appliance scheduling is widely accepted as an effective mechanism to manage domestic energy consumption intelligently. Besides, to residential customers for DR implementation, maintaining a balance between energy consumption cost and users’ comfort satisfaction is a challenge. Hence, in this paper, a constrained Particle Swarm Optimization (PSO)-based residential consumer-centric load-scheduling method is proposed. The method can be further featured with edge computing. In contrast with cloud computing, edge computing—a method of optimizing cloud computing technologies by driving computing capabilities at the IoT edge of the Internet as one of the emerging trends in engineering technology—addresses bandwidth-intensive contents and latency-sensitive applications required among sensors and central data centers through data analytics at or near the source of data. A non-intrusive load-monitoring technique proposed previously is utilized to automatic determination of physical characteristics of power-intensive home appliances from users’ life patterns. The swarm intelligence, constrained PSO, is used to minimize the energy consumption cost while considering users’ comfort satisfaction for DR implementation. The residential consumer-centric load-scheduling method proposed in this paper is evaluated under real-time pricing with inclining block rates and is demonstrated in a case study. The experimentation reported in this paper shows the proposed residential consumer-centric load-scheduling method can re-shape loads by home appliances in response to DR signals. Moreover, a phenomenal reduction in peak power consumption is achieved by 13.97%. PMID:29702607
Diffraction efficiency of radially-profiled off-plane reflection gratings
NASA Astrophysics Data System (ADS)
Miles, Drew M.; Tutt, James H.; DeRoo, Casey T.; Marlowe, Hannah; Peterson, Thomas J.; McEntaffer, Randall L.; Menz, Benedikt; Burwitz, Vadim; Hartner, Gisela; Laubis, Christian; Scholze, Frank
2015-09-01
Future X-ray missions will require gratings with high throughput and high spectral resolution. Blazed off-plane reflection gratings are capable of meeting these demands. A blazed grating profile optimizes grating efficiency, providing higher throughput to one side of zero-order on the arc of diffraction. This paper presents efficiency measurements made in the 0.3 - 1.5 keV energy band at the Physikalisch-Technische Bundesanstalt (PTB) BESSY II facility for three holographically-ruled gratings, two of which are blazed. Each blazed grating was tested in both the Littrow configuration and anti-Littrow configuration in order to test the alignment sensitivity of these gratings with regard to throughput. This paper outlines the procedure of the grating experiment performed at BESSY II and discuss the resulting efficiency measurements across various energies. Experimental results are generally consistent with theory and demonstrate that the blaze does increase throughput to one side of zero-order. However, the total efficiency of the non-blazed, sinusoidal grating is greater than that of the blazed gratings, which suggests that the method of manufacturing these blazed profiles fails to produce facets with the desired level of precision. Finally, evidence of a successful blaze implementation from first diffraction results of prototype blazed gratings produce via a new fabrication technique at the University of Iowa are presented.
Comparison of Strategies for Climate Change Adaptation of Water Supply and Flood Control Reservoirs
NASA Astrophysics Data System (ADS)
Ng, T. L.; Yang, P.; Bhushan, R.
2016-12-01
With climate change, streamflows are expected to become more fluctuating, with more frequent and intense floods and droughts. This complicates reservoir operation, which is highly sensitive to inflow variability. We make a comparative evaluation of three strategies for adapting reservoirs to climate-induced shifts in streamflow patterns. Specifically, we examine the effectiveness of (i) expanding the capacities of reservoirs by way of new off-stream reservoirs, (ii) introducing wastewater reclamation to augment supplies, and (iii) improving real-time streamflow forecasts for more optimal decision-making. The first two are hard strategies involving major infrastructure modifications, while the third a soft strategy entailing adjusting the system operation. A comprehensive side-by-side comparison of the three strategies is as yet lacking in the literature despite the many past studies investigating the strategies individually. To this end, we developed an adaptive forward-looking linear program that solves to yield the optimal decisions for the current time as a function of an ensemble forecast of future streamflows. Solving the model repeatedly on a rolling basis with regular updating of the streamflow forecast simulates the system behavior over the entire operating horizon. Results are generated for two hypothetical water supply and flood control reservoirs of differing inflows and demands. Preliminary findings suggest that of the three strategies, improving streamflow forecasts to be most effective in mitigating the effects of climate change. We also found that, in average terms, both additional reservoir capacity and wastewater reclamation have potential to reduce water shortage and downstream flooding. However, in the worst case, the potential of the former to reduce water shortage is limited, and similarly so the potential of the latter to reduce downstream flooding.
Leveraging human decision making through the optimal management of centralized resources
NASA Astrophysics Data System (ADS)
Hyden, Paul; McGrath, Richard G.
2016-05-01
Combining results from mixed integer optimization, stochastic modeling and queuing theory, we will advance the interdisciplinary problem of efficiently and effectively allocating centrally managed resources. Academia currently fails to address this, as the esoteric demands of each of these large research areas limits work across traditional boundaries. The commercial space does not currently address these challenges due to the absence of a profit metric. By constructing algorithms that explicitly use inputs across boundaries, we are able to incorporate the advantages of using human decision makers. Key improvements in the underlying algorithms are made possible by aligning decision maker goals with the feedback loops introduced between the core optimization step and the modeling of the overall stochastic process of supply and demand. A key observation is that human decision-makers must be explicitly included in the analysis for these approaches to be ultimately successful. Transformative access gives warfighters and mission owners greater understanding of global needs and allows for relationships to guide optimal resource allocation decisions. Mastery of demand processes and optimization bottlenecks reveals long term maximum marginal utility gaps in capabilities.
NASA Astrophysics Data System (ADS)
Momoh, James A.; Salkuti, Surender Reddy
2016-06-01
This paper proposes a stochastic optimization technique for solving the Voltage/VAr control problem including the load demand and Renewable Energy Resources (RERs) variation. The RERs often take along some inputs like stochastic behavior. One of the important challenges i. e., Voltage/VAr control is a prime source for handling power system complexity and reliability, hence it is the fundamental requirement for all the utility companies. There is a need for the robust and efficient Voltage/VAr optimization technique to meet the peak demand and reduction of system losses. The voltages beyond the limit may damage costly sub-station devices and equipments at consumer end as well. Especially, the RERs introduces more disturbances and some of the RERs are not even capable enough to meet the VAr demand. Therefore, there is a strong need for the Voltage/VAr control in RERs environment. This paper aims at the development of optimal scheme for Voltage/VAr control involving RERs. In this paper, Latin Hypercube Sampling (LHS) method is used to cover full range of variables by maximally satisfying the marginal distribution. Here, backward scenario reduction technique is used to reduce the number of scenarios effectively and maximally retain the fitting accuracy of samples. The developed optimization scheme is tested on IEEE 24 bus Reliability Test System (RTS) considering the load demand and RERs variation.
Bandwidth reduction for video-on-demand broadcasting using secondary content insertion
NASA Astrophysics Data System (ADS)
Golynski, Alexander; Lopez-Ortiz, Alejandro; Poirier, Guillaume; Quimper, Claude-Guy
2005-01-01
An optimal broadcasting scheme under the presence of secondary content (i.e. advertisements) is proposed. The proposed scheme works both for movies encoded in a Constant Bit Rate (CBR) or a Variable Bit Rate (VBR) format. It is shown experimentally that secondary content in movies can make Video-on-Demand (VoD) broadcasting systems more efficient. An efficient algorithm is given to compute the optimal broadcasting schedule with secondary content, which in particular significantly improves over the best previously known algorithm for computing the optimal broadcasting schedule without secondary content.
Optimizing the location of ambulances in Tijuana, Mexico.
Dibene, Juan Carlos; Maldonado, Yazmin; Vera, Carlos; de Oliveira, Mauricio; Trujillo, Leonardo; Schütze, Oliver
2017-01-01
In this work we report on modeling the demand for Emergency Medical Services (EMS) in Tijuana, Baja California, Mexico, followed by the optimization of the location of the ambulances for the Red Cross of Tijuana (RCT), which is by far the largest provider of EMS services in the region. We used data from more than 10,000 emergency calls surveyed during the year 2013 to model and classify the demand for EMS in different scenarios that provide different perspectives on the demand throughout the city, considering such factors as the time of day, work and off-days. A modification of the Double Standard Model (DSM) is proposed and solved to determine a common robust solution to the ambulance location problem that simultaneously satisfies all specified constraints in all demand scenarios selecting from a set of almost 1000 possible base locations. The resulting optimization problems are solved using integer linear programming and the solutions are compared with the locations currently used by the Red Cross. Results show that demand coverage and response times can be substantially improved by relocating the current bases without the need for additional resources. Copyright © 2016 Elsevier Ltd. All rights reserved.
Zeng, Jianyang; Zhou, Pei; Donald, Bruce Randall
2011-01-01
One bottleneck in NMR structure determination lies in the laborious and time-consuming process of side-chain resonance and NOE assignments. Compared to the well-studied backbone resonance assignment problem, automated side-chain resonance and NOE assignments are relatively less explored. Most NOE assignment algorithms require nearly complete side-chain resonance assignments from a series of through-bond experiments such as HCCH-TOCSY or HCCCONH. Unfortunately, these TOCSY experiments perform poorly on large proteins. To overcome this deficiency, we present a novel algorithm, called NASCA (NOE Assignment and Side-Chain Assignment), to automate both side-chain resonance and NOE assignments and to perform high-resolution protein structure determination in the absence of any explicit through-bond experiment to facilitate side-chain resonance assignment, such as HCCH-TOCSY. After casting the assignment problem into a Markov Random Field (MRF), NASCA extends and applies combinatorial protein design algorithms to compute optimal assignments that best interpret the NMR data. The MRF captures the contact map information of the protein derived from NOESY spectra, exploits the backbone structural information determined by RDCs, and considers all possible side-chain rotamers. The complexity of the combinatorial search is reduced by using a dead-end elimination (DEE) algorithm, which prunes side-chain resonance assignments that are provably not part of the optimal solution. Then an A* search algorithm is employed to find a set of optimal side-chain resonance assignments that best fit the NMR data. These side-chain resonance assignments are then used to resolve the NOE assignment ambiguity and compute high-resolution protein structures. Tests on five proteins show that NASCA assigns resonances for more than 90% of side-chain protons, and achieves about 80% correct assignments. The final structures computed using the NOE distance restraints assigned by NASCA have backbone RMSD 0.8 – 1.5 Å from the reference structures determined by traditional NMR approaches. PMID:21706248
Simulation of demand management and grid balancing with electric vehicles
NASA Astrophysics Data System (ADS)
Druitt, James; Früh, Wolf-Gerrit
2012-10-01
This study investigates the potential role of electric vehicles in an electricity network with a high contribution from variable generation such as wind power. Electric vehicles are modelled to provide demand management through flexible charging requirements and energy balancing for the network. Balancing applications include both demand balancing and vehicle-to-grid discharging. This study is configured to represent the UK grid with balancing requirements derived from wind generation calculated from weather station wind speeds on the supply side and National Grid data from on the demand side. The simulation models 1000 individual vehicle entities to represent the behaviour of larger numbers of vehicles. A stochastic trip generation profile is used to generate realistic journey characteristics, whilst a market pricing model allows charging and balancing decisions to be based on realistic market price conditions. The simulation has been tested with wind generation capacities representing up to 30% of UK consumption. Results show significant improvements to load following conditions with the introduction of electric vehicles, suggesting that they could substantially facilitate the uptake of intermittent renewable generation. Electric vehicle owners would benefit from flexible charging and selling tariffs, with the majority of revenue derived from vehicle-to-grid participation in balancing markets.
Smart Grid Constraint Violation Management for Balancing and Regulating Purposes
Bhattarai, Bishnu; Kouzelis, Konstantinos; Mendaza, Iker; ...
2017-03-29
The gradual active load penetration in low voltage distribution grids is expected to challenge their network capacity in the near future. Distribution system operators should for this reason resort to either costly grid reinforcements or to demand side management mechanisms. Since demand side management implementation is usually cheaper, it is also the favorable solution. To this end, this article presents a framework for handling grid limit violations, both voltage and current, to ensure a secure and qualitative operation of the distribution grid. This framework consists of two steps, namely a proactive centralized and subsequently a reactive decentralized control scheme. Themore » former is employed to balance the one hour ahead load while the latter aims at regulating the consumption in real-time. In both cases, the importance of fair use of electricity demand flexibility is emphasized. Thus, it is demonstrated that this methodology aids in keeping the grid status within preset limits while utilizing flexibility from all flexibility participants.« less
Optimizing the wireless power transfer over MIMO Channels
NASA Astrophysics Data System (ADS)
Wiedmann, Karsten; Weber, Tobias
2017-09-01
In this paper, the optimization of the power transfer over wireless channels having multiple-inputs and multiple-outputs (MIMO) is studied. Therefore, the transmitter, the receiver and the MIMO channel are modeled as multiports. The power transfer efficiency is described by a Rayleigh quotient, which is a function of the channel's scattering parameters and the incident waves from both transmitter and receiver side. This way, the power transfer efficiency can be maximized analytically by solving a generalized eigenvalue problem, which is deduced from the Rayleigh quotient. As a result, the maximum power transfer efficiency achievable over a given MIMO channel is obtained. This maximum can be used as a performance bound in order to benchmark wireless power transfer systems. Furthermore, the optimal operating point which achieves this maximum will be obtained. The optimal operating point will be described by the complex amplitudes of the optimal incident and reflected waves of the MIMO channel. This supports the design of the optimal transmitter and receiver multiports. The proposed method applies for arbitrary MIMO channels, taking transmitter-side and/or receiver-side cross-couplings in both near- and farfield scenarios into consideration. Special cases are briefly discussed in this paper in order to illustrate the method.
Analysis of an inventory model for both linearly decreasing demand and holding cost
NASA Astrophysics Data System (ADS)
Malik, A. K.; Singh, Parth Raj; Tomar, Ajay; Kumar, Satish; Yadav, S. K.
2016-03-01
This study proposes the analysis of an inventory model for linearly decreasing demand and holding cost for non-instantaneous deteriorating items. The inventory model focuses on commodities having linearly decreasing demand without shortages. The holding cost doesn't remain uniform with time due to any form of variation in the time value of money. Here we consider that the holding cost decreases with respect to time. The optimal time interval for the total profit and the optimal order quantity are determined. The developed inventory model is pointed up through a numerical example. It also includes the sensitivity analysis.
Optimization of a Future RLV Business Case using Multiple Strategic Market Prices
NASA Astrophysics Data System (ADS)
Charania, A.; Olds, J. R.
2002-01-01
There is a lack of depth in the current paradigm of conceptual level economic models used to evaluate the value and viability of future capital projects such as a commercial reusable launch vehicle (RLV). Current modeling methods assume a single price is charged to all customers, public or private, in order to optimize the economic metrics of interest. This assumption may not be valid given the different utility functions for space services of public and private entities. The government's requirements are generally more inflexible than its commercial counterparts. A government's launch schedules are much more rigid, choices of international launch services restricted, and launch specifications generally more stringent as well as numerous. These requirements generally make the government's demand curve more inelastic. Subsequently, a launch vehicle provider will charge a higher price (launch price per kg) to the government and may obtain a higher level of financial profit compared to an equivalent a commercial payload. This profit is not a sufficient condition to enable RLV development by itself but can help in making the financial situation slightly better. An RLV can potentially address multiple payload markets; each market has a different price elasticity of demand for both the commercial and government customer. Thus, a more resilient examination of the economic landscape requires optimization of multiple prices in which each price affects a different demand curve. Such an examination is performed here using the Cost and Business Analysis Module (CABAM), an MS-Excel spreadsheet-based model that attempts to couple both the demand and supply for space transportation services in the future. The demand takes the form of market assumptions (both near-term and far-term) and the supply comes from user-defined vehicles that are placed into the model. CABAM represents RLV projects as commercial endeavors with the possibility to model the effects of government contribution, tax-breaks, loan guarantees, etc. The optimization performed here is for a 3rd Generation RLV program. The economic metric being optimized (maximized) is Net Present Value (NPV) based upon a given company financial structure and cost of capital assumptions. Such an optimization process demands more sophisticated optimizers and can result in non-unique solutions/local minimums if using gradient-based optimization. Domain spanning/evolutionary algorithms are used to obtain the optimized solution in the design space. These capabilities generally increase model calculation time but incorporate realistic pricing portfolios than just assuming one unified price for all launch markets. This analysis is conducted with CABAM running in Phoenix Integration's ModelCenter 4.0 collaborative design environment using the SpaceWorks Engineering, Inc. (SEI) OptWorks suite of optimization components.
1981-01-01
on modeling the managerial aspects of the firm. The second has been the application to economic theory led by ...individual portfolio optimization problems which were embedded in a larger global optimization problem. In the global problem, portfolios were linked by market ...demand quantities or be given by linear demand relationships. As in~ the source markets , the model
Adaptive Decision Making Using Probabilistic Programming and Stochastic Optimization
2018-01-01
world optimization problems (and hence 16 Approved for Public Release (PA); Distribution Unlimited Pred. demand (uncertain; discrete ...simplify the setting, we further assume that the demands are discrete , taking on values d1, . . . , dk with probabilities (conditional on x) (pθ)i ≡ p...Tyrrell Rockafellar. Implicit functions and solution mappings. Springer Monogr. Math ., 2009. Anthony V Fiacco and Yo Ishizuka. Sensitivity and stability
Does the Type of Higher Education Affect Labor Market Outcomes? Evidence from Egypt and Jordan
ERIC Educational Resources Information Center
Assaad, Ragui; Krafft, Caroline; Salehi-Isfahani, Djavad
2018-01-01
In Egypt and Jordan, there is a substantial mismatch between the output of the higher education system and the needs of the labor market. Both demand and supply-side factors could be driving this mismatch. This paper tests a key supply-side issue, whether differences in the institutional structures and incentives in higher education affect the…
Bolsa Escola: Breaking the Cycle of Poverty, Child Labour and School Disaffection in Brazil
ERIC Educational Resources Information Center
Denes, Christian Andrew
2004-01-01
The Bolsa Escola program in Brazil presents a clear break from the economic growth models and supply-side based strategies of the past. Founded on the assumption that the supplemental income generated by child labour outweighs the potential benefits of primary education, Bolsa Escola attempts to address the demand-side component of high dropout…
The role of nuclear energy in mitigating greenhouse warming
DOE Office of Scientific and Technical Information (OSTI.GOV)
Krakowski, R.A.
1997-12-31
A behavioral, top-down, forced-equilibrium market model of long-term ({approximately} 2,100) global energy-economics interactions has been modified with a bottom-up nuclear energy model and used to construct consistent scenarios describing future impacts of civil nuclear materials flows in an expanding, multi-regional (13) world economy. The relative measures and tradeoffs between economic (GNP, tax impacts, productivity, etc.), environmental (greenhouse gas accumulations, waste accumulation, proliferation risk), and energy (resources, energy mixes, supply-side versus demand-side attributes) interactions that emerge from these analyses are focused herein on advancing understanding of the role that nuclear energy (and other non-carbon energy sources) might play in mitigating greenhousemore » warming. Two ostensibly opposing scenario drivers are investigated: (a) demand-side improvements in (non-price-induced) autonomous energy efficiency improvements; and (b) supply-side carbon-tax inducements to shift energy mixes towards reduced- or non-carbon forms. In terms of stemming greenhouse warming for minimal cost of greenhouse-gas abatement, and with the limitations of the simplified taxing schedule used, a symbiotic combination of these two approaches may offer advantages not found if each is applied separately.« less
Sirois-Leclerc, Geneviève; Remaud, Anthony
2017-01-01
Postural control is not a fully automatic process, but requires a certain level of attention, particularly as the difficulty of the postural task increases. This study aimed at testing whether experienced contemporary dancers, because of their specialized training involving the control of posture/balance, would present with a dual-task performance suggesting lesser attentional demands associated with dynamic postural control compared with non-dancers. Twenty dancers and 16 non-dancers performed a dynamic postural tracking task in both antero-posterior and side-to-side directions, while standing on a force platform. The postural task was performed, in turn, 1) as a stand-alone task, and concurrently with both 2) a simple reaction time task and 3) a choice reaction time task. Postural control performance was estimated through variables calculated from centre of pressure movements. Although no overall group difference was found in reaction time values, we found a better ability to control the side to side movements of the centre of pressure during the tracking task in dancers compared with non-dancers, which was dependent on the secondary task. This suggests that such increased ability is influenced by available attentional resources. PMID:28323843
Sirois-Leclerc, Geneviève; Remaud, Anthony; Bilodeau, Martin
2017-01-01
Postural control is not a fully automatic process, but requires a certain level of attention, particularly as the difficulty of the postural task increases. This study aimed at testing whether experienced contemporary dancers, because of their specialized training involving the control of posture/balance, would present with a dual-task performance suggesting lesser attentional demands associated with dynamic postural control compared with non-dancers. Twenty dancers and 16 non-dancers performed a dynamic postural tracking task in both antero-posterior and side-to-side directions, while standing on a force platform. The postural task was performed, in turn, 1) as a stand-alone task, and concurrently with both 2) a simple reaction time task and 3) a choice reaction time task. Postural control performance was estimated through variables calculated from centre of pressure movements. Although no overall group difference was found in reaction time values, we found a better ability to control the side to side movements of the centre of pressure during the tracking task in dancers compared with non-dancers, which was dependent on the secondary task. This suggests that such increased ability is influenced by available attentional resources.
Optimized maritime emergency resource allocation under dynamic demand.
Zhang, Wenfen; Yan, Xinping; Yang, Jiaqi
2017-01-01
Emergency resource is important for people evacuation and property rescue when accident occurs. The relief efforts could be promoted by a reasonable emergency resource allocation schedule in advance. As the marine environment is complicated and changeful, the place, type, severity of maritime accident is uncertain and stochastic, bringing about dynamic demand of emergency resource. Considering dynamic demand, how to make a reasonable emergency resource allocation schedule is challenging. The key problem is to determine the optimal stock of emergency resource for supplier centers to improve relief efforts. This paper studies the dynamic demand, and which is defined as a set. Then a maritime emergency resource allocation model with uncertain data is presented. Afterwards, a robust approach is developed and used to make sure that the resource allocation schedule performs well with dynamic demand. Finally, a case study shows that the proposed methodology is feasible in maritime emergency resource allocation. The findings could help emergency manager to schedule the emergency resource allocation more flexibly in terms of dynamic demand.
Optimized maritime emergency resource allocation under dynamic demand
Yan, Xinping; Yang, Jiaqi
2017-01-01
Emergency resource is important for people evacuation and property rescue when accident occurs. The relief efforts could be promoted by a reasonable emergency resource allocation schedule in advance. As the marine environment is complicated and changeful, the place, type, severity of maritime accident is uncertain and stochastic, bringing about dynamic demand of emergency resource. Considering dynamic demand, how to make a reasonable emergency resource allocation schedule is challenging. The key problem is to determine the optimal stock of emergency resource for supplier centers to improve relief efforts. This paper studies the dynamic demand, and which is defined as a set. Then a maritime emergency resource allocation model with uncertain data is presented. Afterwards, a robust approach is developed and used to make sure that the resource allocation schedule performs well with dynamic demand. Finally, a case study shows that the proposed methodology is feasible in maritime emergency resource allocation. The findings could help emergency manager to schedule the emergency resource allocation more flexibly in terms of dynamic demand. PMID:29240792
Industrial demand side management: A status report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hopkins, M.F.; Conger, R.L.; Foley, T.J.
This report provides an overview of and rationale for industrial demand side management (DSM) programs. Benefits and barriers are described, and data from the Manufacturing Energy Consumption Survey are used to estimate potential energy savings in kilowatt hours. The report presents types and examples of programs and explores elements of successful programs. Two in-depth case studies (from Boise Cascade and Eli Lilly and Company) illustrate two types of effective DSM programs. Interviews with staff from state public utility commissions indicate the current thinking about the status and future of industrial DSM programs. A comprehensive bibliography is included, technical assistance programsmore » are listed and described, and a methodology for evaluating potential or actual savings from projects is delineated.« less
Food security and sustainable intensification
Godfray, H. Charles J.; Garnett, Tara
2014-01-01
The coming decades are likely to see increasing pressures on the global food system, both on the demand side from increasing population and per capita consumption, and on the supply side from greater competition for inputs and from climate change. This paper argues that the magnitude of the challenge is such that action is needed throughout the food system, on moderating demand, reducing waste, improving governance and producing more food. It discusses in detail the last component, arguing that more food should be produced using sustainable intensification (SI) strategies, and explores the rationale behind, and meaning of, this term. It also investigates how SI may interact with other food policy agendas, in particular, land use and biodiversity, animal welfare and human nutrition. PMID:24535385
DOE Office of Scientific and Technical Information (OSTI.GOV)
Waddle, D.B.; MacDonald, J.M.
1990-01-01
In an effort to analyze and document the potential for power sector efficiency improvements from generation to end-use, the Agency for International Development and the Government of Costa Rica are jointly conducting an integrated power sector efficiency analysis. Potential for energy and cost savings in power plants, transmission and distribution, and demand-side management programs are being evaluated. The product of this study will be an integrated investment plan for the Instituto Costarricense de Electricidad, incorporating both supply and demand side investment options. This paper presents the methodology employed in the study, as well as preliminary estimates of the results ofmore » the study. 14 refs., 4 figs., 5 tabs.« less
NASA Astrophysics Data System (ADS)
Wu, Qi
2010-03-01
Demand forecasts play a crucial role in supply chain management. The future demand for a certain product is the basis for the respective replenishment systems. Aiming at demand series with small samples, seasonal character, nonlinearity, randomicity and fuzziness, the existing support vector kernel does not approach the random curve of the sales time series in the space (quadratic continuous integral space). In this paper, we present a hybrid intelligent system combining the wavelet kernel support vector machine and particle swarm optimization for demand forecasting. The results of application in car sale series forecasting show that the forecasting approach based on the hybrid PSOWv-SVM model is effective and feasible, the comparison between the method proposed in this paper and other ones is also given, which proves that this method is, for the discussed example, better than hybrid PSOv-SVM and other traditional methods.
Mansfield, Sarah J
2014-02-01
To assess the degree to which reimbursement prices in Australia and England differ for a range of generic drugs, and to analyse the supply- and demand-side factors that may contribute to these differences. Australian and English reimbursement prices were compared for a range of generic drugs using pricing information obtained from government websites. Next, a literature review was conducted to identify supply- and demand-side factors that could affect generic prices in Australia and England. Various search topics were identified addressing potential supply-side (e.g. market approval, intellectual property protection of patented drugs, generic pricing policy, market size, generic supply chain and discounting practices) and demand-side (consumers, prescribers and pharmacists) factors. Related terms were searched in academic databases, official government websites, national statistical databases and internet search engines. Analysis of drug reimbursement prices for 15 generic molecules (representing 45 different drug presentations) demonstrated that Australian prices were on average over 7-fold higher than in England. Significant supply-side differences included aspects of pricing policy, the relative size of the generics markets and the use of clawback policies. Major differences in demand-side policies related to generic prescribing, pharmacist substitution and consumer incentives. Despite recent reforms, the Australian Government continues to pay higher prices than its English counterpart for many generic medications. The results suggest that particular policy areas may benefit from review in Australia, including the length of the price-setting process, the frequency of subsequent price adjustments, the extent of price competition between originators and generics, medical professionals' knowledge about generic medicines and incentives for generic prescribing. WHAT IS KNOWN ABOUT THE TOPIC? Prices of generic drugs have been the subject of much scrutiny over recent years. From 2005 to 2010 the Australian Government responded to observations that Pharmaceutical Benefits Scheme prices for many generics were higher than in numerous comparable countries by instituting several reforms aimed at reducing the prices of generics. Despite this, several studies have demonstrated that prices for generic statins (one class of cholesterol-lowering drug) are higher in Australia compared with England and many other developed countries, and prices of numerous other generics remain higher than in the USA and New Zealand. Recently there has been increasing interest in why these differences exist. WHAT DOES THIS PAPER ADD? By including a much larger range of commonly used and costly generic drugs, this paper builds significantly on the limited previous investigations of generic drug prices in Australia and England. Additionally, this is the first comprehensive investigation of multiple supply- and, in particular, demand-side factors that may explain any price differences between these countries. WHAT ARE THE IMPLICATIONS FOR PRACTITIONERS? Practitioners may contribute to the higher prices of generic medications in Australia compared with England through relatively low rates of generic prescribing. There are also significant implications for health policy makers, as this paper demonstrates that if Australia achieved the same prices as England for many generic drugs there could be substantial savings for the Pharmaceutical Benefits Scheme.
DSM Electricity Savings Potential in the Buildings Sector in APP Countries
DOE Office of Scientific and Technical Information (OSTI.GOV)
McNeil, MIchael; Letschert, Virginie; Shen, Bo
2011-01-12
The global economy has grown rapidly over the past decade with a commensurate growth in the demand for electricity services that has increased a country's vulnerability to energy supply disruptions. Increasing need of reliable and affordable electricity supply is a challenge which is before every Asia Pacific Partnership (APP) country. Collaboration between APP members has been extremely fruitful in identifying potential efficiency upgrades and implementing clean technology in the supply side of the power sector as well established the beginnings of collaboration. However, significantly more effort needs to be focused on demand side potential in each country. Demand side managementmore » or DSM in this case is a policy measure that promotes energy efficiency as an alternative to increasing electricity supply. It uses financial or other incentives to slow demand growth on condition that the incremental cost needed is less than the cost of increasing supply. Such DSM measures provide an alternative to building power supply capacity The type of financial incentives comprise of rebates (subsidies), tax exemptions, reduced interest loans, etc. Other approaches include the utilization of a cap and trade scheme to foster energy efficiency projects by creating a market where savings are valued. Under this scheme, greenhouse gas (GHG) emissions associated with the production of electricity are capped and electricity retailers are required to meet the target partially or entirely through energy efficiency activities. Implementation of DSM projects is very much in the early stages in several of the APP countries or localized to a regional part of the country. The purpose of this project is to review the different types of DSM programs experienced by APP countries and to estimate the overall future potential for cost-effective demand-side efficiency improvements in buildings sectors in the 7 APP countries through the year 2030. Overall, the savings potential is estimated to be 1.7 thousand TWh or 21percent of the 2030 projected base case electricity demand. Electricity savings potential ranges from a high of 38percent in India to a low of 9percent in Korea for the two sectors. Lighting, fans, and TV sets and lighting and refrigeration are the largest contributors to residential and commercial electricity savings respectively. This work presents a first estimates of the savings potential of DSM programs in APP countries. While the resulting estimates are based on detailed end-use data, it is worth keeping in mind that more work is needed to overcome limitation in data at this time of the project.« less
Schory, Abbey; Bidinger, Erik; Wolf, Joshua
2016-01-01
ABSTRACT Purpose The purpose of this systematic review was to determine the exercises that optimize muscle ratios of the periscapular musculature for scapular stability and isolated strengthening. Methods A systematic search was performed in PubMed, CINAHL, SPORTDiscus, Scopus, and Discovery Layer. Studies were included if they examined the muscle activation of the upper trapezius compared to the middle trapezius, lower trapezius, or serratus anterior using EMG during open chain exercises. The participants were required to have healthy, nonpathological shoulders. Information obtained included maximal voluntary isometric contraction (MVIC) values, ratios, standard deviations, exercises, and exercise descriptions. The outcome of interest was determining exercises that create optimal muscle activation ratios between the scapular stabilizers. Results Fifteen observational studies met the inclusion criteria for the systematic review. Exercises with optimal ratios were eccentric exercises in the frontal and sagittal planes, especially flexion between 180 ° and 60 °. External rotation exercises with the elbow flexed to 90 ° also had optimal ratios for activating the middle trapezius in prone and side-lying positions. Exercises with optimal ratios for the lower trapezius were prone flexion, high scapular retraction, and prone external rotation with the shoulder abducted to 90 ° and elbow flexed. Exercises with optimal ratios for the serratus anterior were the diagonal exercises and scapular protraction. Conclusion This review has identified optimal positions and exercises for periscapular stability exercises. Standing exercises tend to activate the upper trapezius at a higher ratio, especially during the 60-120 ° range. The upper trapezius was the least active, while performing exercises in prone, side-lying, and supine positions. More studies need to be conducted to examine these exercises in greater detail and confirm their consistency in producing the optimal ratios determined in this review. Level of evidence 1a PMID:27274418
On-demand anakinra treatment is effective in mevalonate kinase deficiency.
Bodar, E J; Kuijk, L M; Drenth, J P H; van der Meer, J W M; Simon, A; Frenkel, J
2011-12-01
Mevalonate kinase deficiency (MKD) is a hereditary autoinflammatory syndrome marked by recurrent attacks of fever and inflammation. Severe enzyme deficiency results in mevalonic aciduria (MA) and milder deficiency in hyperimmunoglobulin D syndrome (HIDS). Treatment remains a challenge. To observe the effect of the recombinant interleukin-1 receptor antagonist anakinra in patients with MKD. A prospective observational study was undertaken. Two patients with MA started continuous treatment with anakinra (1-2 mg/kg/day) and nine patients with HIDS chose between continuous treatment and on-demand treatment (starting at first symptoms of attack, 100 mg/day or 1 mg/kg/day for 5-7 days). Anakinra induced partial remission in one patient with MA but there was no response in the other patient with MA. In one patient with HIDS continuous treatment induced complete remission for 7 months but was stopped because of side effects. Eight patients with HIDS preferred on-demand treatment from the start. This induced a clinical response (≥50% reduction in duration) in 8 of 12 treated attacks without a change in attack frequency. Anakinra prevented fever attacks due to vaccination without inhibiting antibody induction. No major side effects were seen. On-demand treatment with anakinra in HIDS decreases the duration and severity of fever attacks. Because of the burden of daily injections and relatively long asymptomatic intervals of HIDS, all patients with HIDS preferred on-demand treatment.
Optimization and resilience of complex supply-demand networks
NASA Astrophysics Data System (ADS)
Zhang, Si-Ping; Huang, Zi-Gang; Dong, Jia-Qi; Eisenberg, Daniel; Seager, Thomas P.; Lai, Ying-Cheng
2015-06-01
Supply-demand processes take place on a large variety of real-world networked systems ranging from power grids and the internet to social networking and urban systems. In a modern infrastructure, supply-demand systems are constantly expanding, leading to constant increase in load requirement for resources and consequently, to problems such as low efficiency, resource scarcity, and partial system failures. Under certain conditions global catastrophe on the scale of the whole system can occur through the dynamical process of cascading failures. We investigate optimization and resilience of time-varying supply-demand systems by constructing network models of such systems, where resources are transported from the supplier sites to users through various links. Here by optimization we mean minimization of the maximum load on links, and system resilience can be characterized using the cascading failure size of users who fail to connect with suppliers. We consider two representative classes of supply schemes: load driven supply and fix fraction supply. Our findings are: (1) optimized systems are more robust since relatively smaller cascading failures occur when triggered by external perturbation to the links; (2) a large fraction of links can be free of load if resources are directed to transport through the shortest paths; (3) redundant links in the performance of the system can help to reroute the traffic but may undesirably transmit and enlarge the failure size of the system; (4) the patterns of cascading failures depend strongly upon the capacity of links; (5) the specific location of the trigger determines the specific route of cascading failure, but has little effect on the final cascading size; (6) system expansion typically reduces the efficiency; and (7) when the locations of the suppliers are optimized over a long expanding period, fewer suppliers are required. These results hold for heterogeneous networks in general, providing insights into designing optimal and resilient complex supply-demand systems that expand constantly in time.
Wu, Yiping; Chen, Ji
2013-01-01
The ever-increasing demand for water due to growth of population and socioeconomic development in the past several decades has posed a worldwide threat to water supply security and to the environmental health of rivers. This study aims to derive reservoir operating rules through establishing a multi-objective optimization model for the Xinfengjiang (XFJ) reservoir in the East River Basin in southern China to minimize water supply deficit and maximize hydropower generation. Additionally, to enhance the estimation of irrigation water demand from the downstream agricultural area of the XFJ reservoir, a conventional method for calculating crop water demand is improved using hydrological model simulation results. Although the optimal reservoir operating rules are derived for the XFJ reservoir with three priority scenarios (water supply only, hydropower generation only, and equal priority), the river environmental health is set as the basic demand no matter which scenario is adopted. The results show that the new rules derived under the three scenarios can improve the reservoir operation for both water supply and hydropower generation when comparing to the historical performance. Moreover, these alternative reservoir operating policies provide the flexibility for the reservoir authority to choose the most appropriate one. Although changing the current operating rules may influence its hydropower-oriented functions, the new rules can be significant to cope with the increasingly prominent water shortage and degradation in the aquatic environment. Overall, our results and methods (improved estimation of irrigation water demand and formulation of the reservoir optimization model) can be useful for local watershed managers and valuable for other researchers worldwide.
NASA Astrophysics Data System (ADS)
Sutrisno; Widowati; Sunarsih; Kartono
2018-01-01
In this paper, a mathematical model in quadratic programming with fuzzy parameter is proposed to determine the optimal strategy for integrated inventory control and supplier selection problem with fuzzy demand. To solve the corresponding optimization problem, we use the expected value based fuzzy programming. Numerical examples are performed to evaluate the model. From the results, the optimal amount of each product that have to be purchased from each supplier for each time period and the optimal amount of each product that have to be stored in the inventory for each time period were determined with minimum total cost and the inventory level was sufficiently closed to the reference level.
Rotstein, Dalia L; Alter, David A
2006-06-01
Waiting for medical care is the by-product of system rationing, where demand exceeds supply. In this short report we expand on the conventional concept of the queue, by focusing on the regulation of demand and by incorporating a funnel and spout analogy. Real-world examples are used to illustrate the infancy of funnel or demand-side reform initiatives targeting the queue, and the suggestion is made that policy needs to address the concept of 'waiting' much earlier in the treatment cycle.
NASA Astrophysics Data System (ADS)
Bonakdari, Hossein; Zaji, Amir Hossein
2018-03-01
In many hydraulic structures, side weirs have a critical role. Accurately predicting the discharge coefficient is one of the most important stages in the side weir design process. In the present paper, a new high efficient side weir is investigated. To simulate the discharge coefficient of these side weirs, three novel soft computing methods are used. The process includes modeling the discharge coefficient with the hybrid Adaptive Neuro-Fuzzy Interface System (ANFIS) and three optimization algorithms, namely Differential Evaluation (ANFIS-DE), Genetic Algorithm (ANFIS-GA) and Particle Swarm Optimization (ANFIS-PSO). In addition, sensitivity analysis is done to find the most efficient input variables for modeling the discharge coefficient of these types of side weirs. According to the results, the ANFIS method has higher performance when using simpler input variables. In addition, the ANFIS-DE with RMSE of 0.077 has higher performance than the ANFIS-GA and ANFIS-PSO methods with RMSE of 0.079 and 0.096, respectively.
Pharmacokinetics of Scopolamine Intranasal Gel Formulation (INSCOP) During Antiorthostatic Bedrest
NASA Technical Reports Server (NTRS)
Putcha, Lakshmi; Boyd, J. L.; Du, B.; Daniels, V.; Crady, C.
2011-01-01
Space Motion sickness (SMS) is an age old problem for space travelers on short and long duration space flight Oral antiemetics are not very effective in space due to poor bioavailability. Scopolamine (SCOP) is the most frequently used drug by recreational travelers V patch, tablets available on the market. Common side effects of antiemetics, in general, include drowsiness, sedation, dry mouth and reduced psychomotor performance. Severity and persistence of side effects are often dose related Side effects can be detrimental in high performance demanding settings, e.g. space flight, military.
ERIC Educational Resources Information Center
Jacob, Brian; McCall, Brian; Stange, Kevin M.
2013-01-01
This paper investigates whether demand-side market pressure explains colleges' decisions to provide consumption amenities to their students. We estimate a discrete choice model of college demand using micro data from the high school classes of 1992 and 2004, matched to extensive information on all four year colleges in the U.S. We find that most…
Patterns of control of maximum metabolic rate in humans.
Hochachka, Peter W; Beatty, Cheryl L
2003-09-01
In this analysis, four performance phenotypes were used to compare mechanisms of control of aerobic maximum metabolic rate (MMR): (i) untrained sedentary (US) subjects, as a reference group against which to compare (ii) power trained (PT), (iii) endurance trained (ET) and (iv) high altitude adapted native (HA) subject groups. Sprinters represented the PT group; long distance runners illustrated the ET group; and Quechuas represented the HA group. Numerous recent studies have identified contributors to control on both the adenosine triphosphate (ATP) supply side and the ATP demand side of ATP turnover. Control coefficients or c(i) values were defined as fractional change in MMR/fractional change in the capacity of any given step in ATP turnover. From the best available evidence it appears that at MMR all five of the major steps in energy delivery (namely, ventilation, pulmonary diffusion, cardiac output, tissue capillary - mitochondrial O(2) transfer, and aerobic cell metabolism per se) approach an upper functional ceiling, with control strength being distributed amongst the various O(2) flux steps. On the energy demand side, the situation is somewhat simplified since at MMR approximately 90% of O(2)-based ATP synthesis is used for actomyosin (AM) and Ca(2+) ATPases; at MMR these two ATP demand rates also appear to be near an upper functional ceiling. In consequence, at MMR the control contributions or c(i) values are rather evenly divided amongst all seven major steps in ATP supply and ATP demand pathways right to the point of fatigue. Relative to US (the reference group), in PT subjects at MMR control strength shifts towards O(2) delivery steps (ventilation, pulmonary diffusion and cardiac output). In contrast in ET and HA subjects at MMR control shifts towards the energy demand steps (AM and Ca(2+) ATPases), and more control strength is focussed on tissue level ATP supply and ATP demand. One obvious advantage of the ET and HA control pattern is improved metabolite homeostasis. Another possibility is that, with some reserve capacity in the O(2) delivery steps and control focussed on ATP turnover at the tissue level, nature has designed the ideal 'endurance machine'.
Control of maximum metabolic rate in humans: dependence on performance phenotypes.
Hochachka, Peter W; Burelle, Yan
2004-01-01
Borrowing from metabolic control analysis the concept of control coefficients or ci values, defined as fractional change in MMR/fractional change in the capacity of any given step in ATP turnover, we used four performance phenotypes to compare mechanisms of control of aerobic maximum metabolic rate (MMR): (i) untrained sedentary (US) subjects, as a reference group against which to compare (ii) power trained (PT), (iii) endurance trained (ET), and (iv) high altitude adapted native (HA) subject groups. Sprinters represented the PT group; long distance runners illustrated the ET group; and Andean natives represented the HA group. Numerous recent studies have identified contributors to control on both the adenosine triphosphate (ATP) supply side and the ATP demand side of ATP turnover. From the best available evidence it appears that at MMR all five of the major steps in energy delivery (namely, ventilation, pulmonary diffusion, cardiac output, tissue capillary--mitochondrial O2 transfer, and aerobic cell metabolism per se) approach an upper functional ceiling, with control strength being distributed amongst the various O2 flux steps. On the energy demand side, the situation is somewhat simplified since at MMR approximately 90% of O2-based ATP synthesis is used for actomyosin (AM) and Ca2+ ATPases; at MMR these two ATP demand rates also appear to be near an upper functional ceiling. In consequence, at MMR the control contributions or ci values are distributed amongst all seven major steps in ATP supply and ATP demand pathways right to the point of fatigue. Relative to US (the reference group), in PT subjects at MMR control strength shifts towards O2 delivery steps (ventilation, pulmonary diffusion, and cardiac output); here physiological regulation clearly dominates MMR control. In contrast in ET and HA subjects at MMR control shifts towards the energy demand steps (AM and Ca2+ ATPases), and more control strength is focussed on tissue level ATP supply and ATP demand. One obvious advantage of the ET and HA biochemical-level control is improved metabolite homeostasis. Additionally, with some reserve capacity in the O2 delivery steps, the focussing of control on ATP turnover at the tissue level has allowed nature to improve on an 'endurance machine' design.
Using Enrollment Demand Models in Institutional Pricing Decisions.
ERIC Educational Resources Information Center
Weiler, William C.
1984-01-01
Issues in the application of enrollment demand analysis to institutions' pricing policy are discussed, including price change impact on enrollment, the role of enrollment demand models on long-range financial and personnel planning, use of tuition and financial aid policy in optimizing policymakers' enrollment objectives, and the redistribution…
Ghosh, Arpita; Laxminarayan, Ramanan
2017-02-15
Although 93% of 12- to 23-month-old children in India receive at least one vaccine, typically Bacillus Calmette-Guérin, only 75% complete the recommended three doses of diphtheria-pertussis-tetanus (DPT, also referred to as DTP) vaccine. Determinants can be different for nonvaccination and dropout but have not been examined in earlier studies. We use the three-dose DPT series as a proxy for the full sequence of recommended childhood vaccines and examine the determinants of DPT nonvaccination and dropout between doses 1 and 3. We analyzed data on 75,728 6- to 23-month-old children in villages across India to study demand- and supply-side factors determining nonvaccination with DPT and dropout between DPT doses 1 and 3, using a multilevel approach. Data come from the District Level Household and Facility Survey 3 (2007-08). Individual- and household-level factors were associated with both DPT nonvaccination and dropout between doses 1 and 3. Children whose mothers had no schooling were 2.3 times more likely not to receive any DPT vaccination and 1.5 times more likely to drop out between DPT doses 1 and 3, compared with children whose mothers had 10 or more years of schooling. Although supply-side factors related to availability of public health facilities and immunization-related health workers in villages were not correlated with dropout between DPT doses 1 and 3, children in districts where 46% or more villages had a healthcare subcentre were 1.5 times more likely to receive at least one dose of DPT vaccine compared with children in districts where 30% or fewer villages had subcentres. Nonvaccination with DPT in India is influenced by village- and district-level contextual factors over and above individuals' background characteristics. Dropout between DPT doses 1 and 3 is associated more strongly with demand-side factors than with village- and district-level supply-side factors. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
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.
Energy management and cooperation in microgrids
NASA Astrophysics Data System (ADS)
Rahbar, Katayoun
Microgrids are key components of future smart power grids, which integrate distributed renewable energy generators to efficiently serve the load demand locally. However, random and intermittent characteristics of renewable energy generations may hinder the reliable operation of microgrids. This thesis is thus devoted to investigating new strategies for microgrids to optimally manage their energy consumption, energy storage system (ESS) and cooperation in real time to achieve the reliable and cost-effective operation. This thesis starts with a single microgrid system. The optimal energy scheduling and ESS management policy is derived to minimize the energy cost of the microgrid resulting from drawing conventional energy from the main grid under both the off-line and online setups, where the renewable energy generation/load demand are assumed to be non-causally known and causally known at the microgrid, respectively. The proposed online algorithm is designed based on the optimal off-line solution and works under arbitrary (even unknown) realizations of future renewable energy generation/load demand. Therefore, it is more practically applicable as compared to solutions based on conventional techniques such as dynamic programming and stochastic programming that require the prior knowledge of renewable energy generation and load demand realizations/distributions. Next, for a group of microgrids that cooperate in energy management, we study efficient methods for sharing energy among them for both fully and partially cooperative scenarios, where microgrids are of common interests and self-interested, respectively. For the fully cooperative energy management, the off-line optimization problem is first formulated and optimally solved, where a distributed algorithm is proposed to minimize the total (sum) energy cost of microgrids. Inspired by the results obtained from the off-line optimization, efficient online algorithms are proposed for the real-time energy management, which are of low complexity and work given arbitrary realizations of renewable energy generation/load demand. On the other hand, for self-interested microgrids, the partially cooperative energy management is formulated and a distributed algorithm is proposed to optimize the energy cooperation such that energy costs of individual microgrids reduce simultaneously over the case without energy cooperation while limited information is shared among the microgrids and the central controller.
Sectoral contributions to surface water stress in the coterminous United States
NASA Astrophysics Data System (ADS)
Averyt, K.; Meldrum, J.; Caldwell, P.; Sun, G.; McNulty, S.; Huber-Lee, A.; Madden, N.
2013-09-01
Here, we assess current stress in the freshwater system based on the best available data in order to understand possible risks and vulnerabilities to regional water resources and the sectors dependent on freshwater. We present watershed-scale measures of surface water supply stress for the coterminous United States (US) using the water supply stress index (WaSSI) model which considers regional trends in both water supply and demand. A snapshot of contemporary annual water demand is compared against different water supply regimes, including current average supplies, current extreme-year supplies, and projected future average surface water flows under a changing climate. In addition, we investigate the contributions of different water demand sectors to current water stress. On average, water supplies are stressed, meaning that demands for water outstrip natural supplies in over 9% of the 2103 watersheds examined. These watersheds rely on reservoir storage, conveyance systems, and groundwater to meet current water demands. Overall, agriculture is the major demand-side driver of water stress in the US, whereas municipal stress is isolated to southern California. Water stress introduced by cooling water demands for power plants is punctuated across the US, indicating that a single power plant has the potential to stress water supplies at the watershed scale. On the supply side, watersheds in the western US are particularly sensitive to low flow events and projected long-term shifts in flow driven by climate change. The WaSSI results imply that not only are water resources in the southwest in particular at risk, but that there are also potential vulnerabilities to specific sectors, even in the ‘water-rich’ southeast.
Load reduction of a monopile wind turbine tower using optimal tuned mass dampers
NASA Astrophysics Data System (ADS)
Tong, Xin; Zhao, Xiaowei; Zhao, Shi
2017-07-01
We investigate to apply tuned mass dampers (TMDs) (one in the fore-aft direction, one in the side-side direction) to suppress the vibration of a monopile wind turbine tower. Using the spectral element method, we derive a finite-dimensional state-space model Σd from an infinite-dimensional model Σ of a monopile wind turbine tower stabilised by a TMD located in the nacelle. Σ and Σd can be used to represent the dynamics of the tower and TMD in either the fore-aft direction or the side-side direction. The wind turbine tower subsystem of Σ is modelled as a non-uniform SCOLE (NASA Spacecraft Control Laboratory Experiment) system consisting of an Euler-Bernoulli beam equation describing the dynamics of the flexible tower and the Newton-Euler rigid body equations describing the dynamics of the heavy rotor-nacelle assembly (RNA) by neglecting any coupling with blade motions. Σd can be used for fast and accurate simulation for the dynamics of the wind turbine tower as well as for optimal TMD designs. We show that Σd agrees very well with the FAST (fatigue, aerodynamics, structures and turbulence) simulation of the NREL 5-MW wind turbine model. We optimise the parameters of the TMD by minimising the frequency-limited ?-norm of the transfer function matrix of Σd which has input of force and torque acting on the RNA, and output of tower-top displacement. The performances of the optimal TMDs in the fore-aft and side-side directions are tested through FAST simulations, which achieve substantial fatigue load reductions. This research also demonstrates how to optimally tune TMDs to reduce vibrations of flexible structures described by partial differential equations.
A Perishable Inventory Model with Return
NASA Astrophysics Data System (ADS)
Setiawan, S. W.; Lesmono, D.; Limansyah, T.
2018-04-01
In this paper, we develop a mathematical model for a perishable inventory with return by assuming deterministic demand and inventory dependent demand. By inventory dependent demand, it means that demand at certain time depends on the available inventory at that time with certain rate. In dealing with perishable items, we should consider deteriorating rate factor that corresponds to the decreasing quality of goods. There are also costs involved in this model such as purchasing, ordering, holding, shortage (backordering) and returning costs. These costs compose the total costs in the model that we want to minimize. In the model we seek for the optimal return time and order quantity. We assume that after some period of time, called return time, perishable items can be returned to the supplier at some returning costs. The supplier will then replace them in the next delivery. Some numerical experiments are given to illustrate our model and sensitivity analysis is performed as well. We found that as the deteriorating rate increases, returning time becomes shorter, the optimal order quantity and total cost increases. When considering the inventory-dependent demand factor, we found that as this factor increases, assuming a certain deteriorating rate, returning time becomes shorter, optimal order quantity becomes larger and the total cost increases.
NASA Technical Reports Server (NTRS)
Donoue, George; Hoffman, Karla; Sherry, Lance; Ferguson, John; Kara, Abdul Qadar
2010-01-01
The air transportation system is a significant driver of the U.S. economy, providing safe, affordable, and rapid transportation. During the past three decades airspace and airport capacity has not grown in step with demand for air transportation; the failure to increase capacity at the same rate as the growth in demand results in unreliable service and systemic delay. This report describes the results of an analysis of airline strategic decision-making that affects geographic access, economic access, and airline finances, extending the analysis of these factors using historic data (from Part 1 of the report). The Airline Schedule Optimization Model (ASOM) was used to evaluate how exogenous factors (passenger demand, airline operating costs, and airport capacity limits) affect geographic access (markets-served, scheduled flights, aircraft size), economic access (airfares), airline finances (profit), and air transportation efficiency (aircraft size). This analysis captures the impact of the implementation of airport capacity limits, as well as the effect of increased hedged fuel prices, which serve as a proxy for increased costs per flight that might occur if auctions or congestion pricing are imposed; also incorporated are demand elasticity curves based on historical data that provide information about how passenger demand is affected by airfare changes.
NASA Astrophysics Data System (ADS)
Zhang, Hao; Chen, Minghua; Parekh, Abhay; Ramchandran, Kannan
2011-09-01
We design a distributed multi-channel P2P Video-on-Demand (VoD) system using "plug-and-play" helpers. Helpers are heterogenous "micro-servers" with limited storage, bandwidth and number of users they can serve simultaneously. Our proposed system has the following salient features: (1) it jointly optimizes over helper-user connection topology, video storage distribution and transmission bandwidth allocation; (2) it minimizes server load, and is adaptable to varying supply and demand patterns across multiple video channels irrespective of video popularity; and (3) it is fully distributed and requires little or no maintenance overhead. The combinatorial nature of the problem and the system demand for distributed algorithms makes the problem uniquely challenging. By utilizing Lagrangian decomposition and Markov chain approximation based arguments, we address this challenge by designing two distributed algorithms running in tandem: a primal-dual storage and bandwidth allocation algorithm and a "soft-worst-neighbor-choking" topology-building algorithm. Our scheme provably converges to a near-optimal solution, and is easy to implement in practice. Packet-level simulation results show that the proposed scheme achieves minimum sever load under highly heterogeneous combinations of supply and demand patterns, and is robust to system dynamics of user/helper churn, user/helper asynchrony, and random delays in the network.
Ideology, Economics and Reader Demand in Soviet Publishing
ERIC Educational Resources Information Center
Walker, G. P. M.
1978-01-01
Examines some of the important assumptions and disputes about publishing as an industry: demand and pricing; profit and subsidy; quality, effectiveness and "optimality"; and the power of the reader. (Author)
Godman, Brian; Wettermark, Bjorn; van Woerkom, Menno; Fraeyman, Jessica; Alvarez-Madrazo, Samantha; Berg, Christian; Bishop, Iain; Bucsics, Anna; Campbell, Stephen; Finlayson, Alexander E; Fürst, Jurij; Garuoliene, Kristina; Herholz, Harald; Kalaba, Marija; Laius, Ott; Piessnegger, Jutta; Sermet, Catherine; Schwabe, Ulrich; Vlahović-Palčevski, Vera V; Markovic-Pekovic, Vanda; Vončina, Luka; Malinowska, Kamila; Zara, Corinne; Gustafsson, Lars L
2014-01-01
The appreciable growth in pharmaceutical expenditure has resulted in multiple initiatives across Europe to lower generic prices and enhance their utilization. However, considerable variation in their use and prices. Assess the influence of multiple supply and demand-side initiatives across Europe for established medicines to enhance prescribing efficiency before a decision to prescribe a particular medicine. Subsequently utilize the findings to suggest potential future initiatives that countries could consider. An analysis of different methodologies involving cross national and single country retrospective observational studies on reimbursed use and expenditure of PPIs, statins, and renin-angiotensin inhibitor drugs among European countries. Nature and intensity of the various initiatives appreciably influenced prescribing behavior and expenditure, e.g., multiple measures resulted in reimbursed expenditure for PPIs in Scotland in 2010 56% below 2001 levels despite a 3-fold increase in utilization and in the Netherlands, PPI expenditure fell by 58% in 2010 vs. 2000 despite a 3-fold increase in utilization. A similar picture was seen with prescribing restrictions, i.e., (i) more aggressive follow-up of prescribing restrictions for patented statins and ARBs resulted in a greater reduction in the utilization of patented statins in Austria vs. Norway and lower utilization of patented ARBs vs. generic ACEIs in Croatia than Austria. However, limited impact of restrictions on esomeprazole in Norway with the first prescription or recommendation in hospital where restrictions do not apply. Similar findings when generic losartan became available in Western Europe. Multiple demand-side measures are needed to influence prescribing patterns. When combined with supply-side measures, activities can realize appreciable savings. Health authorities cannot rely on a "spill over" effect between classes to affect changes in prescribing.
Godman, Brian; Wettermark, Bjorn; van Woerkom, Menno; Fraeyman, Jessica; Alvarez-Madrazo, Samantha; Berg, Christian; Bishop, Iain; Bucsics, Anna; Campbell, Stephen; Finlayson, Alexander E.; Fürst, Jurij; Garuoliene, Kristina; Herholz, Harald; Kalaba, Marija; Laius, Ott; Piessnegger, Jutta; Sermet, Catherine; Schwabe, Ulrich; Vlahović-Palčevski, Vera V.; Markovic-Pekovic, Vanda; Vončina, Luka; Malinowska, Kamila; Zara, Corinne; Gustafsson, Lars L.
2014-01-01
Introduction: The appreciable growth in pharmaceutical expenditure has resulted in multiple initiatives across Europe to lower generic prices and enhance their utilization. However, considerable variation in their use and prices. Objective: Assess the influence of multiple supply and demand-side initiatives across Europe for established medicines to enhance prescribing efficiency before a decision to prescribe a particular medicine. Subsequently utilize the findings to suggest potential future initiatives that countries could consider. Method: An analysis of different methodologies involving cross national and single country retrospective observational studies on reimbursed use and expenditure of PPIs, statins, and renin-angiotensin inhibitor drugs among European countries. Results: Nature and intensity of the various initiatives appreciably influenced prescribing behavior and expenditure, e.g., multiple measures resulted in reimbursed expenditure for PPIs in Scotland in 2010 56% below 2001 levels despite a 3-fold increase in utilization and in the Netherlands, PPI expenditure fell by 58% in 2010 vs. 2000 despite a 3-fold increase in utilization. A similar picture was seen with prescribing restrictions, i.e., (i) more aggressive follow-up of prescribing restrictions for patented statins and ARBs resulted in a greater reduction in the utilization of patented statins in Austria vs. Norway and lower utilization of patented ARBs vs. generic ACEIs in Croatia than Austria. However, limited impact of restrictions on esomeprazole in Norway with the first prescription or recommendation in hospital where restrictions do not apply. Similar findings when generic losartan became available in Western Europe. Conclusions: Multiple demand-side measures are needed to influence prescribing patterns. When combined with supply-side measures, activities can realize appreciable savings. Health authorities cannot rely on a “spill over” effect between classes to affect changes in prescribing. PMID:24987370
2011-02-01
of a multi- year program to develop, optimize, and demonstrate the military viability of a technology for on-demand production of high...continuous reactor system used for kinetic rate data experiment 86 52 Schematic of a differential reactor. The catalyst bed is kept small , and...program to develop, optimize, and demonstrate the military viability of a technology for on-demand production of high-pressure hydrogen for fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wise, B.K.; Hughes, K.R.; Danko, S.L.
1994-07-01
This report was prepared for the US Department of Energy (DOE) Office of Codes and Standards by the Pacific Northwest Laboratory (PNL) through its Building Energy Standards Program (BESP). The purpose of this task was to identify demand-side management (DSM) strategies for new construction that utilities have adopted or developed to promote energy-efficient design and construction. PNL conducted a survey of utilities and used the information gathered to extrapolate lessons learned and to identify evolving trends in utility new-construction DSM programs. The ultimate goal of the task is to identify opportunities where states might work collaboratively with utilities to promotemore » the adoption, implementation, and enforcement of energy-efficient building energy codes.« less
Robust optimization based energy dispatch in smart grids considering demand uncertainty
NASA Astrophysics Data System (ADS)
Nassourou, M.; Puig, V.; Blesa, J.
2017-01-01
In this study we discuss the application of robust optimization to the problem of economic energy dispatch in smart grids. Robust optimization based MPC strategies for tackling uncertain load demands are developed. Unexpected additive disturbances are modelled by defining an affine dependence between the control inputs and the uncertain load demands. The developed strategies were applied to a hybrid power system connected to an electrical power grid. Furthermore, to demonstrate the superiority of the standard Economic MPC over the MPC tracking, a comparison (e.g average daily cost) between the standard MPC tracking, the standard Economic MPC, and the integration of both in one-layer and two-layer approaches was carried out. The goal of this research is to design a controller based on Economic MPC strategies, that tackles uncertainties, in order to minimise economic costs and guarantee service reliability of the system.
Continuous-variable quantum key distribution with a leakage from state preparation
NASA Astrophysics Data System (ADS)
Derkach, Ivan; Usenko, Vladyslav C.; Filip, Radim
2017-12-01
We address side-channel leakage in a trusted preparation station of continuous-variable quantum key distribution with coherent and squeezed states. We consider two different scenarios: multimode Gaussian modulation, directly accessible to an eavesdropper, or side-channel loss of the signal states prior to the modulation stage. We show the negative impact of excessive modulation on both the coherent- and squeezed-state protocols. The impact is more pronounced for squeezed-state protocols and may require optimization of squeezing in the case of noisy quantum channels. Further, we demonstrate that the coherent-state protocol is immune to side-channel signal state leakage prior to modulation, while the squeezed-state protocol is vulnerable to such attacks, becoming more sensitive to the noise in the channel. In the general case of noisy quantum channels the signal squeezing can be optimized to provide best performance of the protocol in the presence of side-channel leakage prior to modulation. Our results demonstrate that leakage from the trusted source in continuous-variable quantum key distribution should not be underestimated and squeezing optimization is needed to overcome coherent state protocols.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Canavan, G.H.
Attack allocation optimizations produce stability indices for unsymmetrical forces that indicate significant regions of both stability and instability and that have their minimum values roughly when the two sides have equal forces. This note derives combined stability indices for unsymmetrical offensive force configurations. The indices are based on optimal allocations of offensive missiles between vulnerable missiles and value based on the minimization of first strike cost, which is done analytically. Exchanges are modeled probabalistically and their results are converted into first and second strike costs through approximations to the damage to the value target sets held at risk. The stabilitymore » index is the product of the ratio of first to second strike costs seen by the two sides. Optimal allocations scale directly on the opponent`s vulnerable missiles, inversely on one`s own total weapons, and only logarithmically on the attacker`s damage preference, kill probability, and relative target set. The defender`s allocation scales in a similar manner on the attacker`s parameters. First and second strike magnitudes increase roughly linearly for the side with greater forces and decrease linearly for the side with fewer. Conversely, the first and second strike magnitudes decrease for the side with greater forces and increase for the side with fewer. These trends are derived and discussed analytically. The resulting stability indices exhibit a minimum where the two sides have roughly equal forces. If one side has much larger forces than the other, his costs drop to levels low enough that he is relatively insensitive to whether he strikes first or second. These calculations are performed with the analytic attack allocation appropriate for moderate forces, so some differences could be expected for the largest of the forces considered.« less
Demand Response Compensation Methodologies: Case Studies for Mexico
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gagne, Douglas A; Settle, Donald E; Aznar, Alexandra Y
This report examines various compensation methodologies for demand response programs in Mexico. This report presents three case studies, including New England, California, and Hawaii. Demand response (DR) can refer to a variety of approaches to changing the amount and timing of customers' electricity use, allowing the electricity supplier to more easily balance electricity supply and demand. The level of compensation for a DR program will depend greatly upon both the regulatory context of the electricity supplier, as well as the economic circumstances of the DR providers. For a regulated utility, a proposed compensation level may need to pass regulatory approval.more » To determine the value of DR resources, a regulatory body typically seeks to determine the costs that the utility would avoid if demand-side resources 'produce' energy.« less
Some Results of Weak Anticipative Concept Applied in Simulation Based Decision Support in Enterprise
NASA Astrophysics Data System (ADS)
Kljajić, Miroljub; Kofjač, Davorin; Kljajić Borštnar, Mirjana; Škraba, Andrej
2010-11-01
The simulation models are used as for decision support and learning in enterprises and in schools. Tree cases of successful applications demonstrate usefulness of weak anticipative information. Job shop scheduling production with makespan criterion presents a real case customized flexible furniture production optimization. The genetic algorithm for job shop scheduling optimization is presented. Simulation based inventory control for products with stochastic lead time and demand describes inventory optimization for products with stochastic lead time and demand. Dynamic programming and fuzzy control algorithms reduce the total cost without producing stock-outs in most cases. Values of decision making information based on simulation were discussed too. All two cases will be discussed from optimization, modeling and learning point of view.
MDO can help resolve the designer's dilemma. [multidisciplinary design optimization
NASA Technical Reports Server (NTRS)
Sobieszczanski-Sobieski, Jaroslaw; Tulinius, Jan R.
1991-01-01
Multidisciplinary design optimization (MDO) is presented as a rapidly growing body of methods, algorithms, and techniques that will provide a quantum jump in the effectiveness and efficiency of the quantitative side of design, and will turn that side into an environment in which the qualitative side can thrive. MDO borrows from CAD/CAM for graphic visualization of geometrical and numerical data, data base technology, and in computer software and hardware. Expected benefits from this methodology are a rational, mathematically consistent approach to hypersonic aircraft designs, designs pushed closer to the optimum, and a design process either shortened or leaving time available for different concepts to be explored.
Ryu, Joonghyun; Lee, Mokwon; Cha, Jehyun; Laskowski, Roman A.; Ryu, Seong Eon; Kim, Deok-Soo
2016-01-01
Many applications, such as protein design, homology modeling, flexible docking, etc. require the prediction of a protein's optimal side-chain conformations from just its amino acid sequence and backbone structure. Side-chain prediction (SCP) is an NP-hard energy minimization problem. Here, we present BetaSCPWeb which efficiently computes a conformation close to optimal using a geometry-prioritization method based on the Voronoi diagram of spherical atoms. Its outputs are visual, textual and PDB file format. The web server is free and open to all users at http://voronoi.hanyang.ac.kr/betascpweb with no login requirement. PMID:27151195
NASA Astrophysics Data System (ADS)
Pando, V.; García-Laguna, J.; San-José, L. A.
2012-11-01
In this article, we integrate a non-linear holding cost with a stock-dependent demand rate in a maximising profit per unit time model, extending several inventory models studied by other authors. After giving the mathematical formulation of the inventory system, we prove the existence and uniqueness of the optimal policy. Relying on this result, we can obtain the optimal solution using different numerical algorithms. Moreover, we provide a necessary and sufficient condition to determine whether a system is profitable, and we establish a rule to check when a given order quantity is the optimal lot size of the inventory model. The results are illustrated through numerical examples and the sensitivity of the optimal solution with respect to changes in some values of the parameters is assessed.
Charging stations location model based on spatiotemporal electromobility use patterns
NASA Astrophysics Data System (ADS)
Pagany, Raphaela; Marquardt, Anna; Zink, Roland
2016-04-01
One of the major challenges for mainstream adoption of electric vehicles is the provision of infrastructure for charging the batteries of the vehicles. The charging stations must not only be located dense enough to allow users to complete their journeys, but the electric energy must also be provided from renewable sources in order to truly offer a transportation with less CO2 emissions. The examination of potential locations for the charging of electric vehicles can facilitate the adaption of electromobility and the integration of electronic vehicles in everyday life. A geographic information system (GIS) based model for optimal location of charging stations in a small and regional scale is presented. This considers parameters such as the forecast of electric vehicle use penetration, the relevant weight of diverse point of interests and the distance between parking area and destination for different vehicle users. In addition to the spatial scale the temporal modelling of the energy demand at the different charging locations has to be considerate. Depending on different user profiles (commuters, short haul drivers etc.) the frequency of charging vary during the day, the week and the year. In consequence, the spatiotemporal variability is a challenge for a reliable energy supply inside a decentralized renewable energy system. The presented model delivers on the one side the most adequate identified locations for charging stations and on the other side the interaction between energy supply and demand for electromobility under the consideration of temporal aspects. Using ESRI ArcGIS Desktop, first results for the case study region of Lower Bavaria are generated. The aim of the concept is to keep the model transferable to other regions and also open to integrate further and more detailed user profiles, derived from social studies about i.e. the daily behavior and the perception of electromobility in a next step.
NASA Astrophysics Data System (ADS)
Huang, Yeu-Shiang; Wang, Ruei-Pei; Ho, Jyh-Wen
2015-07-01
Due to the constantly changing business environment, producers often have to deal with customers by adopting different procurement policies. That is, manufacturers confront not only predictable and regular orders, but also unpredictable and irregular orders. In this study, from the perspective of upstream manufacturers, both regular and irregular orders are considered in coping with the situation in which an uncertain demand is faced by the manufacturer, and a capacity confirming mechanism is used to examine such demand. If the demand is less than or equal to the capacity of the ordinary production channel, the general supply channel is utilised to fully account for the manufacturing process, but if the demand is greater than the capacity of the ordinary production channel, the contingency production channel would be activated along with the ordinary channel to satisfy the upcoming high demand. Besides, the reproductive property of the probability distribution is employed to represent the order quantity of the two types of demand. Accordingly, the optimal production rates and lot sizes for both channels are derived to provide managers with insights for further production planning.
Optimal strategy analysis based on robust predictive control for inventory system with random demand
NASA Astrophysics Data System (ADS)
Saputra, Aditya; Widowati, Sutrisno
2017-12-01
In this paper, the optimal strategy for a single product single supplier inventory system with random demand is analyzed by using robust predictive control with additive random parameter. We formulate the dynamical system of this system as a linear state space with additive random parameter. To determine and analyze the optimal strategy for the given inventory system, we use robust predictive control approach which gives the optimal strategy i.e. the optimal product volume that should be purchased from the supplier for each time period so that the expected cost is minimal. A numerical simulation is performed with some generated random inventory data. We simulate in MATLAB software where the inventory level must be controlled as close as possible to a set point decided by us. From the results, robust predictive control model provides the optimal strategy i.e. the optimal product volume that should be purchased and the inventory level was followed the given set point.
ERIC Educational Resources Information Center
Kapustin, S. A.
2016-01-01
The article presents the results of applying the existential criterion of normal and abnormal personalities for assessing the personality of overprotective and overly demanding parents in 176 families of patients who have sought psychological counseling. It is shown that the position of overprotective parents is one-sided in relation to the…
Participation in Non-Formal Learning in EU-15 and EU-8 Countries: Demand and Supply Side Factors
ERIC Educational Resources Information Center
Roosmaa, Eve-Liis; Saar, Ellu
2012-01-01
The main purpose of this paper is to provide an in-depth analysis of participation in non-formal learning in different European Union member states. The paper also seeks to extend analysis of the training gap by pursuing the distinction between the supply and the demand for skills. We use aggregate data from the Adult Education Survey (Eurostat)…
Zhang, Y M; Huang, G; Lu, H W; He, Li
2015-08-15
A key issue facing integrated water resources management and water pollution control is to address the vague parametric information. A full credibility-based chance-constrained programming (FCCP) method is thus developed by introducing the new concept of credibility into the modeling framework. FCCP can deal with fuzzy parameters appearing concurrently in the objective and both sides of the constraints of the model, but also provide a credibility level indicating how much confidence one can believe the optimal modeling solutions. The method is applied to Heshui River watershed in the south-central China for demonstration. Results from the case study showed that groundwater would make up for the water shortage in terms of the shrinking surface water and rising water demand, and the optimized total pumpage of groundwater from both alluvial and karst aquifers would exceed 90% of its maximum allowable levels when credibility level is higher than or equal to 0.9. It is also indicated that an increase in credibility level would induce a reduction in cost for surface water acquisition, a rise in cost from groundwater withdrawal, and negligible variation in cost for water pollution control. Copyright © 2015 Elsevier B.V. All rights reserved.
Nowak, Karl; Mix, Eilhard; Gimsa, Jan; Strauss, Ulf; Sriperumbudur, Kiran Kumar; Benecke, Reiner; Gimsa, Ulrike
2011-01-01
Deep brain stimulation (DBS) has become a treatment for a growing number of neurological and psychiatric disorders, especially for therapy-refractory Parkinson's disease (PD). However, not all of the symptoms of PD are sufficiently improved in all patients, and side effects may occur. Further progress depends on a deeper insight into the mechanisms of action of DBS in the context of disturbed brain circuits. For this, optimized animal models have to be developed. We review not only charge transfer mechanisms at the electrode/tissue interface and strategies to increase the stimulation's energy-efficiency but also the electrochemical, electrophysiological, biochemical and functional effects of DBS. We introduce a hemi-Parkinsonian rat model for long-term experiments with chronically instrumented rats carrying a backpack stimulator and implanted platinum/iridium electrodes. This model is suitable for (1) elucidating the electrochemical processes at the electrode/tissue interface, (2) analyzing the molecular, cellular and behavioral stimulation effects, (3) testing new target regions for DBS, (4) screening for potential neuroprotective DBS effects, and (5) improving the efficacy and safety of the method. An outlook is given on further developments of experimental DBS, including the use of transgenic animals and the testing of closed-loop systems for the direct on-demand application of electric stimulation. PMID:21603182
Electrolyzers Enhancing Flexibility in Electric Grids
Mohanpurkar, Manish; Luo, Yusheng; Terlip, Danny; ...
2017-11-10
This paper presents a real-time simulation with a hardware-in-the-loop (HIL)-based approach for verifying the performance of electrolyzer systems in providing grid support. Hydrogen refueling stations may use electrolyzer systems to generate hydrogen and are proposed to have the potential of becoming smarter loads that can proactively provide grid services. On the basis of experimental findings, electrolyzer systems with balance of plant are observed to have a high level of controllability and hence can add flexibility to the grid from the demand side. A generic front end controller (FEC) is proposed, which enables an optimal operation of the load on themore » basis of market and grid conditions. This controller has been simulated and tested in a real-time environment with electrolyzer hardware for a performance assessment. It can optimize the operation of electrolyzer systems on the basis of the information collected by a communication module. Real-time simulation tests are performed to verify the performance of the FEC-driven electrolyzers to provide grid support that enables flexibility, greater economic revenue, and grid support for hydrogen producers under dynamic conditions. In conclusion, the FEC proposed in this paper is tested with electrolyzers, however, it is proposed as a generic control topology that is applicable to any load.« less
The role of chemistry in the energy challenge.
Schlögl, Robert
2010-02-22
Chemistry with its key targets of providing materials and processes for conversion of matter is at the center stage of the energy challenge. Most energy conversion systems work on (bio)chemical energy carriers and require for their use suitable process and material solutions. The enormous scale of their application demands optimization beyond the incremental improvement of empirical discoveries. Knowledge-based systematic approaches are mandatory to arrive at scalable and sustainable solutions. Chemistry for energy, "ENERCHEM" contributes in many ways already today to the use of fossil energy carriers. Optimization of these processes exemplified by catalysis for fuels and chemicals production or by solid-state lightning can contribute in the near future substantially to the dual challenge of energy use and climate protection being in fact two sides of the same challenge. The paper focuses on the even greater role that ENERCHEM will have to play in the era of renewable energy systems where the storage of solar energy in chemical carries and batteries is a key requirement. A multidisciplinary and diversified approach is suggested to arrive at a stable and sustainable system of energy conversion processes. The timescales for transformation of the present energy scenario will be decades and the resources will be of global economic dimensions. ENERCHEM will have to provide the reliable basis for such technologies based on deep functional understanding.
The supply and demand for pollution control: Evidence from wastewater treatment
McConnell, V.D.; Schwarz, G.E.
1992-01-01
This paper analyzes the determination of pollution control from wastewater treatment plants as an economic decision facing local or regional regulators. Pollution control is measured by plant design effluent concentration levels and is fully endogenous in a supply- and-demand model of treatment choice. On the supply side, plant costs are a function of the design treatment level of the plant, and on the demand side, treatment level is a function of both the costs of control and the regional or regulatory preferences for control. We find evidence that the economic model of effluent choice by local regulators has a good deal of explanatory power. We find evidence that wastewater treatment plant removal of biological oxygen demand (BOD) is sensitive to many local factors including the size of the treatment plant, the flow rate of the receiving water, the population density of the surrounding area, regional growth, state sensitivity to environmental issues, state income, and the extent to which the damages from pollution fall on other states. We find strong evidence that regulators are sensitive to capital costs in determining the design level of BOD effluent reduction at a plant. Thus, proposed reductions in federal subsidies for wastewater treatment plant construction are likely to have significant adverse effects on water quality. ?? 1992.
NASA Astrophysics Data System (ADS)
Cao, Yang; Liu, Chun; Huang, Yuehui; Wang, Tieqiang; Sun, Chenjun; Yuan, Yue; Zhang, Xinsong; Wu, Shuyun
2017-02-01
With the development of roof photovoltaic power (PV) generation technology and the increasingly urgent need to improve supply reliability levels in remote areas, islanded microgrid with photovoltaic and energy storage systems (IMPE) is developing rapidly. The high costs of photovoltaic panel material and energy storage battery material have become the primary factors that hinder the development of IMPE. The advantages and disadvantages of different types of photovoltaic panel materials and energy storage battery materials are analyzed in this paper, and guidance is provided on material selection for IMPE planners. The time sequential simulation method is applied to optimize material demands of the IMPE. The model is solved by parallel algorithms that are provided by a commercial solver named CPLEX. Finally, to verify the model, an actual IMPE is selected as a case system. Simulation results on the case system indicate that the optimization model and corresponding algorithm is feasible. Guidance for material selection and quantity demand for IMPEs in remote areas is provided by this method.
NASA Astrophysics Data System (ADS)
Teoh, Lay Eng; Khoo, Hooi Ling
2013-09-01
This study deals with two major aspects of airlines, i.e. supply and demand management. The aspect of supply focuses on the mathematical formulation of an optimal fleet management model to maximize operational profit of the airlines while the aspect of demand focuses on the incorporation of mode choice modeling as parts of the developed model. The proposed methodology is outlined in two-stage, i.e. Fuzzy Analytic Hierarchy Process is first adopted to capture mode choice modeling in order to quantify the probability of probable phenomena (for aircraft acquisition/leasing decision). Then, an optimization model is developed as a probabilistic dynamic programming model to determine the optimal number and types of aircraft to be acquired and/or leased in order to meet stochastic demand during the planning horizon. The findings of an illustrative case study show that the proposed methodology is viable. The results demonstrate that the incorporation of mode choice modeling could affect the operational profit and fleet management decision of the airlines at varying degrees.
Encouraging the use of generic medicines: implications for transition economies.
King, Derek R; Kanavos, Panos
2002-08-01
Generic drugs have a key role to play in the efficient allocation of financial resources for pharmaceutical medicines. Policies implemented in the countries with a high rate of generic drug use, such as Canada, Denmark, Germany, the Netherlands, the United Kingdom, and the United States, are reviewed, with consideration of the market structures that facilitate strong competition. Savings in these countries are realized through increases in the volume of generic drugs used and the frequently significant differences in the price between generic medicines and branded originator medicines. Their policy tools include the mix of supply-side measures and demand-side measures that are relevant for generic promotion and higher generic use. On the supply-side, key policy measures include generic drug marketing regulation that facilitates market entry soon after patent expiration, reference pricing, the pricing of branded originator products, and the degree of price competition in pharmaceutical markets. On the demand-side, measures typically encompass influencing prescribing and dispensing patterns as well as introducing a co-payment structure for consumers/patients that takes into consideration the difference in cost between branded and generic medicines. Quality of generic medicines is a pre-condition for all other measures discussed to take effect. The paper concludes by offering a list of policy options for decision-makers in Central and Eastern European economies in transition.
Household water demand and welfare loss for future Europe
NASA Astrophysics Data System (ADS)
Bernhard, Jeroen; Reynaud, Arnaud; Lanzanova, Denis; de Roo, Ad
2015-04-01
Matching the availability of water to its demand in Europe is a major challenge for the future due to expected economic and demographic developments and climate change. This means there is a growing need to estimate future water demand and to optimize the water allocation to all end users to counteract welfare loss. At the European scale it is currently not possible to assess the impact of social and economic changes on future water demand or to prioritize water allocation amongst different sectors based on economic damage without extensive use of assumptions and generalizations. Indeed, our review of existing regional optimization models for Europe reveals that the social-economic component of the water use system needs to be improved by complementing them with detailed water use estimates and cost/benefit functions in order to determine the optimal situation. Our study contributes to closing this knowledge gap for the European household sector by quantifying future water demand and the effect of water pricing, as well as providing a method for the calculation of monetary damage due to unmet demand at the highest spatial resolution possible. We used a water demand function approach in which household water consumption depends upon some exogenous drivers including water price, household income, population and household characteristics and climate conditions. For each European country, the annual water consumption per capita was calculated at regional level (NUTS3) and subsequently disaggregated to five kilometer grid level based on a population density map. In order to produce estimates of water demand, the evolution of the explanatory variables of the water demand functions and population density map were simulated until 2050 based on related variables such as GDP and demographic projections. The results of this study will be integrated into the JRC hydro-economic modelling framework for an assessment of the Water-Agriculture-Energy-Ecosystems Nexus.
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.
Synthesis of optimal usage of available aggregates in highway construction and maintenance.
DOT National Transportation Integrated Search
2009-11-01
The optimization of available aggregates for highway construction and maintenance is vital both from an economic and environmental perspective. By not optimizing the aggregate supply, project costs escalate as a simple response to supply and demand. ...
The Production Rate and Employment of Ph.D. Astronomers
NASA Astrophysics Data System (ADS)
Metcalfe, Travis S.
2008-02-01
In an effort to encourage self-regulation of the astronomy job market, I examine the supply of, and demand for, astronomers over time. On the supply side, I document the production rate of Ph.D. astronomers from 1970 to 2006 using the UMI Dissertation Abstracts database, along with data from other independent sources. I compare the long-term trends in Ph.D. production with federal astronomy research funding over the same time period, and I demonstrate that additional funding is correlated with higher subsequent Ph.D. production. On the demand side, I monitor the changing patterns of employment using statistics about the number and types of jobs advertised in the AAS Job Register from 1984 to 2006. Finally, I assess the sustainability of the job market by normalizing this demand by the annual Ph.D. production. The most recent data suggest that there are now annual advertisements for about one postdoctoral job, half a faculty job, and half a research/support position for every new domestic Ph.D. recipient in astronomy and astrophysics. The average new astronomer might expect to hold up to 3 jobs before finding a steady position.
Intermittent Renewable Management Pilot Phase 2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kiliccote, Sila; Homan, Gregory; Anderson, Robert
The Intermittent Renewable Management Pilot - Phase 2 (IRM2) was designed to study the feasibility of demand-side resources to participate into the California Independent System Operator (CAISO) wholesale market as proxy demand resources (PDR). The pilot study focused on understanding the issues related with direct participation of third-parties and customers including customer acceptance; market transformation challenges (wholesale market, technology); technical and operational feasibility; and value to the rate payers, DR resource owners and the utility on providing an enabling mechanism for DR resources into the wholesale markets. The customer had the option of committing to either three contiguous hour blocksmore » for 24 days or six contiguous hours for 12 days a month with day-ahead notification that aligned with the CAISO integrated forward market. As a result of their being available, the customer was paid $10/ kilowatt (kW)-month for capacity in addition to CAISO energy settlements. The participants were limited to no more than a 2 megawatt (MW) capacity with a six-month commitment. Four participants successfully engaged in the pilot. In this report, we provide the description of the pilot, participant performance results, costs and value to participants as well as outline some of the issues encountered through the pilot. Results show that participants chose to participate with storage and the value of CAISO settlements were significantly lower than the capacity payments provided by the utility as incentive payments. In addition, this pilot revealed issues both on the participant side and system operations side. These issues are summarized in the report.The Intermittent Renewable Management Pilot - Phase 2 (IRM2) was designed to study the feasibility of demand-side resources to participate into the California Independent System Operator (CAISO) wholesale market as proxy demand resources (PDR). The pilot study focused on understanding the issues related with direct participation of third-parties and customers including customer acceptance; market transformation challenges (wholesale market, technology); technical and operational feasibility; and value to the rate payers, DR resource owners and the utility on providing an enabling mechanism for DR resources into the wholesale markets.« less
Ahmed, Shakil; Khan, M Mahmud
2011-05-01
Demand-side financing (DSF) is used in the less-developed countries of the world to improve access to healthcare and to encourage market supply. Under DSF, households receive vouchers that can be used to pay for healthcare services. This study evaluated the effects of a universal DSF on maternal healthcare service utilization in Bangladesh. A household survey was conducted in and around the voucher scheme area one year after the initiation of the project. Women who gave birth within a year prior to the survey were interviewed. The utilization rates of maternal health services were found to be higher for all socioeconomic groups in the project area than in the comparison areas. Voucher recipients in the project area were 3.6 times more likely to be assisted by skilled health personnel during delivery, 2.5 times more likely to deliver the baby in a health facility, 2.8 times more likely to receive postnatal care (PNC), 2.0 times more likely to get antenatal care (ANC) services and 1.5 times more likely to seek treatment for obstetric complications than pregnant women not in the program. The degree of socioeconomic inequality in maternal health service utilization was also lower in the project area than in the comparison area. The use of vouchers evidenced much stronger demand-increasing effects on the poor. Poor voucher recipients were 4.3 times more likely to deliver in a health facility and two times more likely to use skilled health personnel at delivery than the non-poor recipients. Contrary to the inverse equity hypothesis, the voucher scheme reduced inequality even in the short run. Despite these improvements, socioeconomic disparity in the use of maternal health services has remained pro-rich, implying that demand-side financing alone will be insufficient to achieve the Millennium Development Goal for maternal health. A comprehensive system-wide approach, including supply-side strengthening, will be needed to adequately address maternal health concerns in poor developing countries. Copyright © 2011 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Corbett, Jacqueline Marie
Enabled by advanced communication and information technologies, the smart grid represents a major transformation for the electricity sector. Vast quantities of data and two-way communications abilities create the potential for a flexible, data-driven, multi-directional supply and consumption network well equipped to meet the challenges of the next century. For electricity service providers ("utilities"), the smart grid provides opportunities for improved business practices and new business models; however, a transformation of such magnitude is not without risks. Three related studies are conducted to explore the implications of the smart grid on utilities' demand-side activities. An initial conceptual framework, based on organizational information processing theory, suggests that utilities' performance depends on the fit between the information processing requirements and capacities associated with a given demand-side activity. Using secondary data and multiple regression analyses, the first study finds, consistent with OIPT, a positive relationship between utilities' advanced meter deployments and demand-side management performance. However, it also finds that meters with only data collection capacities are associated with lower performance, suggesting the presence of information waste causing operational inefficiencies. In the second study, interviews with industry participants provide partial support for the initial conceptual model, new insights are gained with respect to information processing fit and information waste, and "big data" is identified as a central theme of the smart grid. To derive richer theoretical insights, the third study employs a grounded theory approach examining the experience of one successful utility in detail. Based on interviews and documentary data, the paradox of dynamic stability emerges as an essential enabler of utilities' performance in the smart grid environment. Within this context, the frames of opportunity, control, and data limitation interact to support dynamic stability and contribute to innovation within tradition. The main contributions of this thesis include theoretical extensions to OIPT and the development of an emergent model of dynamic stability in relation to big data. The thesis also adds to the green IS literature and identifies important practical implications for utilities as they endeavour to bring the smart grid to reality.
Fadel, Salah; Hajbi, Youssef; Khouili, Mostafa; Lazar, Said
2014-01-01
Summary Substituted 3,4-dihydro-1,8-naphthyridin-2(1H)-ones have been synthesized with the inverse electron-demand Diels–Alder reaction from 1,2,4-triazines bearing an acylamino group with a terminal alkyne side chain. Alkynes were first subjected to the Sonogashira cross-coupling reaction with aryl halides, the product of which then underwent an intramolecular inverse electron-demand Diels–Alder reaction to yield 5-aryl-3,4-dihydro-1,8-naphthyridin-2(1H)-ones by an efficient synthetic route. PMID:24605148
Fadel, Salah; Hajbi, Youssef; Khouili, Mostafa; Lazar, Said; Suzenet, Franck; Guillaumet, Gérald
2014-01-01
Substituted 3,4-dihydro-1,8-naphthyridin-2(1H)-ones have been synthesized with the inverse electron-demand Diels-Alder reaction from 1,2,4-triazines bearing an acylamino group with a terminal alkyne side chain. Alkynes were first subjected to the Sonogashira cross-coupling reaction with aryl halides, the product of which then underwent an intramolecular inverse electron-demand Diels-Alder reaction to yield 5-aryl-3,4-dihydro-1,8-naphthyridin-2(1H)-ones by an efficient synthetic route.
Landry, Michel D; Hack, Laurita M; Coulson, Elizabeth; Freburger, Janet; Johnson, Michael P; Katz, Richard; Kerwin, Joanne; Smith, Megan H; Wessman, Henry C Bud; Venskus, Diana G; Sinnott, Patricia L; Goldstein, Marc
2016-01-01
Health human resources continue to emerge as a critical health policy issue across the United States. The purpose of this study was to develop a strategy for modeling future workforce projections to serve as a basis for analyzing annual supply of and demand for physical therapists across the United States into 2020. A traditional stock-and-flow methodology or model was developed and populated with publicly available data to produce estimates of supply and demand for physical therapists by 2020. Supply was determined by adding the estimated number of physical therapists and the approximation of new graduates to the number of physical therapists who immigrated, minus US graduates who never passed the licensure examination, and an estimated attrition rate in any given year. Demand was determined by using projected US population with health care insurance multiplied by a demand ratio in any given year. The difference between projected supply and demand represented a shortage or surplus of physical therapists. Three separate projection models were developed based on best available data in the years 2011, 2012, and 2013, respectively. Based on these projections, demand for physical therapists in the United States outstrips supply under most assumptions. Workforce projection methodology research is based on assumptions using imperfect data; therefore, the results must be interpreted in terms of overall trends rather than as precise actuarial data-generated absolute numbers from specified forecasting. Outcomes of this projection study provide a foundation for discussion and debate regarding the most effective and efficient ways to influence supply-side variables so as to position physical therapists to meet current and future population demand. Attrition rates or permanent exits out of the profession can have important supply-side effects and appear to have an effect on predicting future shortage or surplus of physical therapists. © 2016 American Physical Therapy Association.
Zhao, Pengfei; Zheng, Mingbin; Luo, Zhenyu; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Zheng, Cuifang; Ma, Yifan; Cai, Lintao
2015-09-24
Smart nanoparticles (NPs) that respond to external and internal stimulations have been developing to achieve optimal drug release in tumour. However, applying these smart NPs to attain high antitumour performance is hampered by limited drug carriers and inefficient spatiotemporal control. Here we report a noninvasive NIR-driven, temperature-sensitive DI-TSL (DOX/ICG-loaded temperature sensitive liposomes) co-encapsulating doxorubicin (DOX) and indocyanine green (ICG). This theranostic system applies thermo-responsive lipid to controllably release drug, utilizes the fluorescence (FL) of DOX/ICG to real-time trace the distribution of NPs, and employs DOX/ICG to treat cancer by chemo/photothermal therapy. DI-TSL exhibits uniform size distribution, excellent FL/size stability, enhanced response to NIR-laser, and 3 times increased drug release through laser irradiation. After endocytosis by MCF-7 breast adenocarcinoma cells, DI-TSL in cellular endosomes can cause hyperthermia through laser irradiation, then endosomes are disrupted and DI-TSL 'opens' to release DOX simultaneously for increased cytotoxicity. Furthermore, DI-TSL shows laser-controlled release of DOX in tumour, enhanced ICG and DOX retention by 7 times and 4 times compared with free drugs. Thermo-sensitive DI-TSL manifests high efficiency to promote cell apoptosis, and completely eradicate tumour without side-effect. DI-TSL may provide a smart strategy to release drugs on demand for combinatorial cancer therapy.
NASA Astrophysics Data System (ADS)
Zhao, Pengfei; Zheng, Mingbin; Luo, Zhenyu; Gong, Ping; Gao, Guanhui; Sheng, Zonghai; Zheng, Cuifang; Ma, Yifan; Cai, Lintao
2015-09-01
Smart nanoparticles (NPs) that respond to external and internal stimulations have been developing to achieve optimal drug release in tumour. However, applying these smart NPs to attain high antitumour performance is hampered by limited drug carriers and inefficient spatiotemporal control. Here we report a noninvasive NIR-driven, temperature-sensitive DI-TSL (DOX/ICG-loaded temperature sensitive liposomes) co-encapsulating doxorubicin (DOX) and indocyanine green (ICG). This theranostic system applies thermo-responsive lipid to controllably release drug, utilizes the fluorescence (FL) of DOX/ICG to real-time trace the distribution of NPs, and employs DOX/ICG to treat cancer by chemo/photothermal therapy. DI-TSL exhibits uniform size distribution, excellent FL/size stability, enhanced response to NIR-laser, and 3 times increased drug release through laser irradiation. After endocytosis by MCF-7 breast adenocarcinoma cells, DI-TSL in cellular endosomes can cause hyperthermia through laser irradiation, then endosomes are disrupted and DI-TSL ‘opens’ to release DOX simultaneously for increased cytotoxicity. Furthermore, DI-TSL shows laser-controlled release of DOX in tumour, enhanced ICG and DOX retention by 7 times and 4 times compared with free drugs. Thermo-sensitive DI-TSL manifests high efficiency to promote cell apoptosis, and completely eradicate tumour without side-effect. DI-TSL may provide a smart strategy to release drugs on demand for combinatorial cancer therapy.
Effects of knowing the task duration on players' pacing patterns during soccer small-sided games.
Ferraz, Ricardo; Gonçalves, Bruno; Van Den Tillaar, Roland; Jiménez Sáiz, Sergio; Sampaio, Jaime; Marques, Mário C
2018-01-01
The aim of this study was to identify the influence of prior knowledge of exercise duration on players' pacing patterns during soccer small-sided games. Twenty semi-professional male soccer players participated in this study. In the first game scenario, players were not informed how long they would be required to play the small-sided game and the activity was terminated after 20 min (Unknown Condition). In the second game scenario, players were told that they would play the small-sided game for 10 min, but immediately after completing the 10-min game, they were asked to complete another 10 min (Partially Condition). In the third game scenario, players were instructed that they would play the small-sided game for 20 min and then they completed the 20-min game (Known Condition). The results presented a tendency of higher values in all performance variables in the [0'-10'] min compared with the [10'-20'] min. As the players' previous knowledge about the tasks duration increased, the performance between two moments tended to be similar. Considering the entire 20-min game duration, the Partially Condition of the exercise was the most demanding condition. In conclusion, the knowledge of shorter durations of the exercise seems to lead to an increase of exercise duration demand, and longer exercise durations possibly tend to decrease differences between full knowledge and not knowing the exercise duration.
Optimized active traffic management and speed harmonization in work zones.
DOT National Transportation Integrated Search
2014-01-01
Traffic and demand management are major strategies to control delay and congestion in : highway bottlenecks including work zones. The Federal Highway Administration (FHWA) : introduced innovative strategies, called Active Traffic and Demand Managemen...
Terminal alkenes as versatile chemical reporter groups for metabolic oligosaccharide engineering.
Späte, Anne-Katrin; Schart, Verena F; Schöllkopf, Sophie; Niederwieser, Andrea; Wittmann, Valentin
2014-12-08
The Diels-Alder reaction with inverse electron demand (DAinv reaction) of 1,2,4,5-tetrazines with electron rich or strained alkenes was proven to be a bioorthogonal ligation reaction that proceeds fast and with high yields. An important application of the DAinv reaction is metabolic oligosaccharide engineering (MOE) which allows the visualization of glycoconjugates in living cells. In this approach, a sugar derivative bearing a chemical reporter group is metabolically incorporated into cellular glycoconjugates and subsequently derivatized with a probe by means of a bioorthogonal ligation reaction. Here, we investigated a series of new mannosamine and glucosamine derivatives with carbamate-linked side chains of varying length terminated by alkene groups and their suitability for labeling cell-surface glycans. Kinetic investigations showed that the reactivity of the alkenes in DAinv reactions increases with growing chain length. When applied to MOE, one of the compounds, peracetylated N-butenyloxycarbonylmannosamine, was especially well suited for labeling cell-surface glycans. Obviously, the length of its side chain represents the optimal balance between incorporation efficiency and speed of the labeling reaction. Sialidase treatment of the cells before the bioorthogonal labeling reaction showed that this sugar derivative is attached to the glycans in form of the corresponding sialic acid derivative and not epimerized to another hexosamine derivative to a considerable extent. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Wideband Low Side Lobe Aperture Coupled Patch Phased Array Antennas
NASA Astrophysics Data System (ADS)
Poduval, Dhruva
Low profile printed antenna arrays with wide bandwidth, high gain, and low Side Lobe Level (SLL) are in great demand for current and future commercial and military communication systems and radar. Aperture coupled patch antennas have been proposed to obtain wide impedance bandwidths in the past. Aperture coupling is preferred particularly for phased arrays because of their advantage of integration to other active devices and circuits, e.g. phase shifters, power amplifiers, low noise amplifiers, mixers etc. However, when designing such arrays, the interplay between array performance characteristics, such as gain, side lobe level, back lobe level, mutual coupling etc. must be understood and optimized under multiple design constraints, e.g. substrate material properties and thicknesses, element to element spacing, and feed lines and their orientation and arrangements with respect to the antenna elements. The focus of this thesis is to investigate, design, and develop an aperture coupled patch array with wide operating bandwidth (30%), high gain (17.5 dBi), low side lobe level (20 dB), and high Forward to Backward (F/B) ratio (21.8 dB). The target frequency range is 2.4 to 3 GHz given its wide application in WLAN, LTE (Long Term Evolution) and other communication systems. Notwithstanding that the design concept can very well be adapted at other frequencies. Specifically, a 16 element, 4 by 4 planar microstrip patch array is designed using HFSS and experimentally developed and tested. Starting from mutual coupling minimization a corporate feeding scheme is designed to achieve the needed performance. To reduce the SLL the corporate feeding network is redesigned to obtain a specific amplitude taper. Studies are conducted to determine the optimum location for a metallic reflector under the feed line to improve the F/B. An experimental prototype of the antenna was built and tested validating and demonstrating the performance levels expected from simulation predictions. Finally, simulated beam scanning in several angles of the array is shown considering specific phases for each antenna element in the array.
Youssef, Yassar; Lee, Gyusung; Godinez, Carlos; Sutton, Erica; Klein, Rosemary V; George, Ivan M; Seagull, F Jacob; Park, Adrian
2011-07-01
This study compares surgical techniques and surgeon's standing position during laparoscopic cholecystectomy (LC), investigating each with respect to surgeons' learning, performance, and ergonomics. Little homogeneity exists in LC performance and training. Variations in standing position (side-standing technique vs. between-standing technique) and hand technique (one-handed vs. two-handed) exist. Thirty-two LC procedures performed on a virtual reality simulator were video-recorded and analyzed. Each subject performed four different procedures: one-handed/side-standing, one-handed/between-standing, two-handed/side-standing, and two-handed/between-standing. Physical ergonomics were evaluated using Rapid Upper Limb Assessment (RULA). Mental workload assessment was acquired with the National Aeronautics and Space Administration-Task Load Index (NASA-TLX). Virtual reality (VR) simulator-generated performance evaluation and a subjective survey were analyzed. RULA scores were consistently lower (indicating better ergonomics) for the between-standing technique and higher (indicating worse ergonomics) for the side-standing technique, regardless of whether one- or two-handed. Anatomical scores overall showed side-standing to have a detrimental effect on the upper arms and trunk. The NASA-TLX showed significant association between the side-standing position and high physical demand, effort, and frustration (p<0.05). The two-handed technique in the side-standing position required more effort than the one-handed (p<0.05). No difference in operative time or complication rate was demonstrated among the four procedures. The two-handed/between-standing method was chosen as the best procedure to teach and standardize. Laparoscopic cholecystectomy poses a risk of physical injury to the surgeon. As LC is currently commonly performed in the United States, the left side-standing position may lead to increased physical demand and effort, resulting in ergonomically unsound conditions for the surgeon. Though further investigations should be conducted, adopting the between-standing position deserves serious consideration as it may be the best short-term ergonomic alternative.
Weininger, Ulrich; Respondek, Michal; Akke, Mikael
2012-09-01
Protein dynamics on the millisecond time scale commonly reflect conformational transitions between distinct functional states. NMR relaxation dispersion experiments have provided important insights into biologically relevant dynamics with site-specific resolution, primarily targeting the protein backbone and methyl-bearing side chains. Aromatic side chains represent attractive probes of protein dynamics because they are over-represented in protein binding interfaces, play critical roles in enzyme catalysis, and form an important part of the core. Here we introduce a method to characterize millisecond conformational exchange of aromatic side chains in selectively (13)C labeled proteins by means of longitudinal- and transverse-relaxation optimized CPMG relaxation dispersion. By monitoring (13)C relaxation in a spin-state selective manner, significant sensitivity enhancement can be achieved in terms of both signal intensity and the relative exchange contribution to transverse relaxation. Further signal enhancement results from optimizing the longitudinal relaxation recovery of the covalently attached (1)H spins. We validated the L-TROSY-CPMG experiment by measuring fast folding-unfolding kinetics of the small protein CspB under native conditions. The determined unfolding rate matches perfectly with previous results from stopped-flow kinetics. The CPMG-derived chemical shift differences between the folded and unfolded states are in excellent agreement with those obtained by urea-dependent chemical shift analysis. The present method enables characterization of conformational exchange involving aromatic side chains and should serve as a valuable complement to methods developed for other types of protein side chains.
Impact of intravenous nitroglycerin in the management of acute decompensated heart failure.
den Uil, Corstiaan A; Brugts, Jasper J
2015-02-01
Intravenous nitroglycerin is a well-known, but underused, treatment for acute decompensated heart failure. Nitroglycerin has a rapid onset of action and short half-life and there is a clear dose-response curve on both global hemodynamics and peripheral circulation. IV nitroglycerin reduces LV and RV filling pressures and afterload. In the case of acute decompensated heart failure, there is a typical decreased bioavailability of nitric oxide (NO), which needs to be supplemented by exogenous nitrates. Additionally, there is benefit on clinical endpoints, such as fast optimization of arterial oxygenation, lower rates of mechanical ventilation, and improved survival. Drawbacks of therapy include not only side effects such as headache, resistance, and development of tolerability to nitrates but also free radical production. However, nitrates in combination with diuretics remain the cornerstone of acute decompensated heart failure treatment. We propose a more aggressive use of nitrates and a more limited use of inotropes (due to ischemic demand and pro-arrhythmogenic characteristics) in normo- or hypertensive patients with acute heart failure.
NASA Astrophysics Data System (ADS)
Taneja, Jayant Kumar
Electricity is an indispensable commodity to modern society, yet it is delivered via a grid architecture that remains largely unchanged over the past century. A host of factors are conspiring to topple this dated yet venerated design: developments in renewable electricity generation technology, policies to reduce greenhouse gas emissions, and advances in information technology for managing energy systems. Modern electric grids are emerging as complex distributed systems in which a portfolio of power generation resources, often incorporating fluctuating renewable resources such as wind and solar, must be managed dynamically to meet uncontrolled, time-varying demand. Uncertainty in both supply and demand makes control of modern electric grids fundamentally more challenging, and growing portfolios of renewables exacerbate the challenge. We study three electricity grids: the state of California, the province of Ontario, and the country of Germany. To understand the effects of increasing renewables, we develop a methodology to scale renewables penetration. Analyzing these grids yields key insights about rigid limits to renewables penetration and their implications in meeting long-term emissions targets. We argue that to achieve deep penetration of renewables, the operational model of the grid must be inverted, changing the paradigm from load-following supplies to supply-following loads. To alleviate the challenge of supply-demand matching on deeply renewable grids, we first examine well-known techniques, including altering management of existing supply resources, employing utility-scale energy storage, targeting energy efficiency improvements, and exercising basic demand-side management. Then, we create several instantiations of supply-following loads -- including refrigerators, heating and cooling systems, and laptop computers -- by employing a combination of sensor networks, advanced control techniques, and enhanced energy storage. We examine the capacity of each load for supply-following and study the behaviors of populations of these loads, assessing their potential at various levels of deployment throughout the California electricity grid. Using combinations of supply-following strategies, we can reduce peak natural gas generation by 19% on a model of the California grid with 60% renewables. We then assess remaining variability on this deeply renewable grid incorporating supply-following loads, characterizing additional capabilities needed to ensure supply-demand matching in future sustainable electricity grids.
Rainwater harvesting systems for low demanding applications.
Sanches Fernandes, Luís F; Terêncio, Daniela P S; Pacheco, Fernando A L
2015-10-01
A rainwater harvesting system (RHS) was designed for a waste treatment facility located near the town of Mirandela (northern Portugal), to be used in the washing of vehicles and other equipment, the cleaning of outside concrete or asphalt floors, and the watering of green areas. Water tank volumes representing 100% efficiency (Vr) were calculated by the Ripple method with different results depending on two consumption scenarios adopted for irrigation. The RHS design was based on a precipitation record spanning a rather long period (3 decades). The calculated storage capacities fulfilled the water demand even when prolonged droughts occurred during that timeframe. However, because the drought events have been rather scarce the Vr values were considered oversized and replaced by optimal volumes. Notwithstanding the new volumes were solely half of the original Vr values, the projected RHS efficiency remained very high (around 90%) while the probability of system failure (efficiency<100%) stayed very low (in the order of 5%). In both scenarios, the economic savings related to the optimization of Vr were noteworthy, while the investment's return periods decreased substantially from the original to the optimized solutions. A high efficiency with a low storage capacity is typical of low demanding applications of rainwater harvesting, where water availability (Vw) largely exceeds water demand (Cw), that is to say where demand fractions (Cw/Vw) are very low. Based on the results of a literature review covering an ample geographic distribution and describing a very large number of demand fraction scenarios, a Cw/Vw=0.8 was defined as the threshold to generally distinguish the low from the high demanding RHS applications. Copyright © 2015 Elsevier B.V. All rights reserved.
Wang, Hui; Liu, Chunyue; Rong, Luge; Wang, Xiaoxu; Sun, Lina; Luo, Qing; Wu, Hao
2018-01-09
River monitoring networks play an important role in water environmental management and assessment, and it is critical to develop an appropriate method to optimize the monitoring network. In this study, an effective method was proposed based on the attainment rate of National Grade III water quality, optimal partition analysis and Euclidean distance, and Hun River was taken as a method validation case. There were 7 sampling sites in the monitoring network of the Hun River, and 17 monitoring items were analyzed once a month during January 2009 to December 2010. The results showed that the main monitoring items in the surface water of Hun River were ammonia nitrogen (NH 4 + -N), chemical oxygen demand, and biochemical oxygen demand. After optimization, the required number of monitoring sites was reduced from seven to three, and 57% of the cost was saved. In addition, there were no significant differences between non-optimized and optimized monitoring networks, and the optimized monitoring networks could correctly represent the original monitoring network. The duplicate setting degree of monitoring sites decreased after optimization, and the rationality of the monitoring network was improved. Therefore, the optimal method was identified as feasible, efficient, and economic.
Molecular modeling of calmodulin: a comparison with crystallographic data
NASA Technical Reports Server (NTRS)
McDonald, J. J.; Rein, R.
1989-01-01
Two methods of side-chain placement on a modeled protein have been examined. Two molecular models of calmodulin were constructed that differ in the treatment of side chains prior to optimization of the molecule. A virtual bond analysis program developed by Purisima and Scheraga was used to determine the backbone conformation based on 2.2 angstroms resolution C alpha coordinates for the molecules. In the first model, side chains were initially constructed in an extended conformation. In the second model, a conformational grid search technique was employed. Calcium ions were treated explicitly during energy optimization using CHARMM. The models are compared to a recently published refined crystal structure of calmodulin. The results indicate that the initial choices for side-chains, but also significant effects on the main-chain conformation and supersecondary structure. The conformational differences are discussed. Analysis of these and other methods makes possible the formulation of a methodology for more appropriate side-chain placement in modeled proteins.
Wu, Jian Sheng; Si, Meng Lin; Li, Wei Feng
2016-09-01
Urban green space is an important ecological landscape, whose spatial distribution plays a significant role in improving the eco-environment and people's living quality. This study was initia-ted from the perspective of supply and demand balance to evaluate the equity of distribution of urban parks, drawing on previous research, and introduced an integrated framework for evaluating the equity of urban public facilities using spatial multi-analysis. A method concerning gravity model to assess the equity of urban green space was introduced, taking the effect of boundary into account. The case study area was the Futian District of Shenzhen and its 2000 m buffer area. Then, some optimizations were suggested for better allocation of the green space. The results showed that the equity of Futian District was low. The equity of community parks was lowest, followed by that of regional parks, while the countryside ecological parks owned the highest equity. About 50% of the Futian district area was in a state of balance between supply and demand and the rest were in a state of insufficient supply. Greening rate and space allocation of parks and road traffic systems should be improved to better plan the green space in Futian District. For urban green space planning, the parks of small area should be paid more attention to meet the needs of residents for daily recreation. By taking the effect of boundary into account, we observed that the residential area on the edge of the study area could enjoy the park green space, and the green space in the boundary area outside the region would be also shared by residents on both sides of the administrative boundary.
Water-resources optimization model for Santa Barbara, California
Nishikawa, Tracy
1998-01-01
A simulation-optimization model has been developed for the optimal management of the city of Santa Barbara's water resources during a drought. The model, which links groundwater simulation with linear programming, has a planning horizon of 5 years. The objective is to minimize the cost of water supply subject to: water demand constraints, hydraulic head constraints to control seawater intrusion, and water capacity constraints. The decision variables are montly water deliveries from surface water and groundwater. The state variables are hydraulic heads. The drought of 1947-51 is the city's worst drought on record, and simulated surface-water supplies for this period were used as a basis for testing optimal management of current water resources under drought conditions. The simulation-optimization model was applied using three reservoir operation rules. In addition, the model's sensitivity to demand, carry over [the storage of water in one year for use in the later year(s)], head constraints, and capacity constraints was tested.
NASA Astrophysics Data System (ADS)
Osman, Ayat E.
Energy use in commercial buildings constitutes a major proportion of the energy consumption and anthropogenic emissions in the USA. Cogeneration systems offer an opportunity to meet a building's electrical and thermal demands from a single energy source. To answer the question of what is the most beneficial and cost effective energy source(s) that can be used to meet the energy demands of the building, optimizations techniques have been implemented in some studies to find the optimum energy system based on reducing cost and maximizing revenues. Due to the significant environmental impacts that can result from meeting the energy demands in buildings, building design should incorporate environmental criteria in the decision making criteria. The objective of this research is to develop a framework and model to optimize a building's operation by integrating congregation systems and utility systems in order to meet the electrical, heating, and cooling demand by considering the potential life cycle environmental impact that might result from meeting those demands as well as the economical implications. Two LCA Optimization models have been developed within a framework that uses hourly building energy data, life cycle assessment (LCA), and mixed-integer linear programming (MILP). The objective functions that are used in the formulation of the problems include: (1) Minimizing life cycle primary energy consumption, (2) Minimizing global warming potential, (3) Minimizing tropospheric ozone precursor potential, (4) Minimizing acidification potential, (5) Minimizing NOx, SO 2 and CO2, and (6) Minimizing life cycle costs, considering a study period of ten years and the lifetime of equipment. The two LCA optimization models can be used for: (a) long term planning and operational analysis in buildings by analyzing the hourly energy use of a building during a day and (b) design and quick analysis of building operation based on periodic analysis of energy use of a building in a year. A Pareto-optimal frontier is also derived, which defines the minimum cost required to achieve any level of environmental emission or primary energy usage value or inversely the minimum environmental indicator and primary energy usage value that can be achieved and the cost required to achieve that value.
Two retailer-supplier supply chain models with default risk under trade credit policy.
Wu, Chengfeng; Zhao, Qiuhong
2016-01-01
The purpose of the paper is to formulate two uncooperative replenishment models with demand and default risk which are the functions of the trade credit period, i.e., a Nash equilibrium model and a supplier-Stackelberg model. Firstly, we present the optimal results of decentralized decision and centralized decision without trade credit. Secondly, we derive the existence and uniqueness conditions of the optimal solutions under the two games, respectively. Moreover, we present a set of theorems and corollary to determine the optimal solutions. Finally, we provide an example and sensitivity analysis to illustrate the proposed strategy and optimal solutions. Sensitivity analysis reveals that the total profits of supply chain under the two games both are better than the results under the centralized decision only if the optimal trade credit period isn't too short. It also reveals that the size of trade credit period, demand, retailer's profit and supplier's profit have strong relationship with the increasing demand coefficient, wholesale price, default risk coefficient and production cost. The major contribution of the paper is that we comprehensively compare between the results of decentralized decision and centralized decision without trade credit, Nash equilibrium and supplier-Stackelberg models with trade credit, and obtain some interesting managerial insights and practical implications.
Taking side effects into account for HIV medication.
Costanza, Vicente; Rivadeneira, Pablo S; Biafore, Federico L; D'Attellis, Carlos E
2010-09-01
A control-theoretic approach to the problem of designing "low-side-effects" therapies for HIV patients based on highly active drugs is substantiated here. The evolution of side effects during treatment is modeled by an extra differential equation coupled to the dynamics of virions, healthy T-cells, and infected ones. The new equation reflects the dependence of collateral damages on the amount of each dose administered to the patient and on the evolution of the viral load detected by periodical blood analysis. The cost objective accounts for recommended bounds on healthy cells and virions, and also penalizes the appearance of collateral morbidities caused by the medication. The optimization problem is solved by a hybrid dynamic programming scheme that adhere to discrete-time observation and control actions, but by maintaining the continuous-time setup for predicting states and side effects. The resulting optimal strategies employ less drugs than those prescribed by previous optimization studies, but maintaining high doses at the beginning and the end of each period of six months. If an inverse discount rate is applied to favor early actions, and under a mild penalization of the final viral load, then the optimal doses are found to be high at the beginning and decrease afterward, thus causing an apparent stabilization of the main variables. But in this case, the final viral load turns higher than acceptable.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lin, Zhenhong; Liu, Changzheng; Yin, Yafeng
The objective of this study is to evaluate the opportunity for public charging for a subset of US cities by using available public parking lot data. The capacity of the parking lots weighted by the daily parking occupancy rate is used as a proxy for daily parking demand. The city s public charging opportunity is defined as the percentage of parking demand covered by chargers on the off-street parking network. We assess this opportunity under the scenario of optimal deployment of public chargers. We use the maximum coverage model to optimally locate those facilities on the public garage network. Wemore » compare the optimal results to the actual placement of chargers. These empirical findings are of great interest to policymakers as those showcase the potential of increasing opportunities for charging under optimal charging location planning.« less
Enhancing Nursing Staffing Forecasting With Safety Stock Over Lead Time Modeling.
McNair, Douglas S
2015-01-01
In balancing competing priorities, it is essential that nursing staffing provide enough nurses to safely and effectively care for the patients. Mathematical models to predict optimal "safety stocks" have been routine in supply chain management for many years but have up to now not been applied in nursing workforce management. There are various aspects that exhibit similarities between the 2 disciplines, such as an evolving demand forecast according to acuity and the fact that provisioning "stock" to meet demand in a future period has nonzero variable lead time. Under assumptions about the forecasts (eg, the demand process is well fit as an autoregressive process) and about the labor supply process (≥1 shifts' lead time), we show that safety stock over lead time for such systems is effectively equivalent to the corresponding well-studied problem for systems with stationary demand bounds and base stock policies. Hence, we can apply existing models from supply chain analytics to find the optimal safety levels of nurse staffing. We use a case study with real data to demonstrate that there are significant benefits from the inclusion of the forecast process when determining the optimal safety stocks.
EM&V for Energy Efficiency Policies and Initiatives
Learn how representatives of jurisdictions, companies, and other entities can use evaluation, measurement, and verification (EM&V) in demand-side energy efficiency (EE) investments to achieve intended environmental, energy, and economic goals.
Future directions: Integrated resource planning
NASA Astrophysics Data System (ADS)
Bauer, D. C.; Eto, J.
Integrated resource planning or IRP is the process for integrating supply- and demand-side resources to provide energy services at a cost that balances the interests of all stakeholders. It now is the resource planning process used by electric utilities in over 30 states. The goals of IRP have evolved from least cost planning and encouragement of demand-side management to broader, more complex issues including core competitive business activity, risk management and sharing, accounting for externalities, and fuel switching between gas and electricity. IRP processes are being extended to other interior regions of the country, to non-investor owned utilities, and to regional (rather than individual utility) planning bases, and to other fuels (natural gas). The comprehensive, multi-valued, and public reasoning characteristics of IRP could be extended to applications beyond energy, e.g., transportation, surface water management, and health care in ways suggested.
1988-08-01
least; but my partners will have to respect the points I value. [LE SOIR] You once compared Martens to Caligula , and here you are working side by...side with him! [Louis Tobback] I even said that Martens was worse than Caligula . But I was not comparing people, and those who only remember...to ratify a special powers act and then demanded it be ratified because the Council of State said so. Caligula once made the Roman Senate appoint
Ryu, Joonghyun; Lee, Mokwon; Cha, Jehyun; Laskowski, Roman A; Ryu, Seong Eon; Kim, Deok-Soo
2016-07-08
Many applications, such as protein design, homology modeling, flexible docking, etc. require the prediction of a protein's optimal side-chain conformations from just its amino acid sequence and backbone structure. Side-chain prediction (SCP) is an NP-hard energy minimization problem. Here, we present BetaSCPWeb which efficiently computes a conformation close to optimal using a geometry-prioritization method based on the Voronoi diagram of spherical atoms. Its outputs are visual, textual and PDB file format. The web server is free and open to all users at http://voronoi.hanyang.ac.kr/betascpweb with no login requirement. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.
Trading the Economic Value of Unsatisfied Municipal Water Demand
NASA Astrophysics Data System (ADS)
Telfah, Dua'a. B.; Minciardi, Riccardo; Roth, Giorgio
2018-06-01
Modelling and optimization techniques for water resources allocation are proposed to identify the economic value of the unsatisfied municipal water demand against demands emerging from other sectors. While this is always an important step in integrated water resource management perspective, it became crucial for water scarce Countries. In fact, since the competition for the resource is high, they are in crucial need to trade values which will help them in satisfying their policies and needs. In this framework, hydro-economic, social equity and environmental constraints need to be satisfied. In the present study, a hydro-economic decision model based on optimization schemes has been developed for water resources allocation, that enable the evaluation of the economic cost of a deficiency in fulfilling the municipal demand. Moreover, the model enables efficient water resources management, satisfying the demand and proposing additional water resources options. The formulated model is designed to maximize the demand satisfaction and minimize water production cost subject to system priorities, preferences and constraints. The demand priorities are defined based on the effect of demand dissatisfaction, while hydrogeological and physical characteristics of the resources are embedded as constraints in the optimization problem. The application to the City of Amman is presented. Amman is the Capital City of the Hashemite Kingdom of Jordan, a Country located in the south-eastern area of the Mediterranean, on the East Bank of the Jordan River. The main challenge for Jordan, that threat the development and prosperity of all sectors, is the extreme water scarcity. In fact, Jordan is classified as semi-arid to arid region with limited financial resources and unprecedented population growth. While the easy solution directly goes to the simple but expensive approach to cover the demand, case study results show that the proposed model plays a major role in providing directions to decision makers to orient their policies and strategies in order to achieve sustainability of scarce water resources, satisfaction of the minimum required demand as well as financial sustainability. In addition, results map out national needs and priorities that are crucial in understanding and controlling the complexity of Jordan's water sector, mainly for the city of Amman.
NASA Astrophysics Data System (ADS)
Zatarain Salazar, Jazmin; Reed, Patrick M.; Quinn, Julianne D.; Giuliani, Matteo; Castelletti, Andrea
2017-11-01
Reservoir operations are central to our ability to manage river basin systems serving conflicting multi-sectoral demands under increasingly uncertain futures. These challenges motivate the need for new solution strategies capable of effectively and efficiently discovering the multi-sectoral tradeoffs that are inherent to alternative reservoir operation policies. Evolutionary many-objective direct policy search (EMODPS) is gaining importance in this context due to its capability of addressing multiple objectives and its flexibility in incorporating multiple sources of uncertainties. This simulation-optimization framework has high potential for addressing the complexities of water resources management, and it can benefit from current advances in parallel computing and meta-heuristics. This study contributes a diagnostic assessment of state-of-the-art parallel strategies for the auto-adaptive Borg Multi Objective Evolutionary Algorithm (MOEA) to support EMODPS. Our analysis focuses on the Lower Susquehanna River Basin (LSRB) system where multiple sectoral demands from hydropower production, urban water supply, recreation and environmental flows need to be balanced. Using EMODPS with different parallel configurations of the Borg MOEA, we optimize operating policies over different size ensembles of synthetic streamflows and evaporation rates. As we increase the ensemble size, we increase the statistical fidelity of our objective function evaluations at the cost of higher computational demands. This study demonstrates how to overcome the mathematical and computational barriers associated with capturing uncertainties in stochastic multiobjective reservoir control optimization, where parallel algorithmic search serves to reduce the wall-clock time in discovering high quality representations of key operational tradeoffs. Our results show that emerging self-adaptive parallelization schemes exploiting cooperative search populations are crucial. Such strategies provide a promising new set of tools for effectively balancing exploration, uncertainty, and computational demands when using EMODPS.
Benchmark of Client and Server-Side Catchment Delineation Approaches on Web-Based Systems
NASA Astrophysics Data System (ADS)
Demir, I.; Sermet, M. Y.; Sit, M. A.
2016-12-01
Recent advances in internet and cyberinfrastructure technologies have provided the capability to acquire large scale spatial data from various gauges and sensor networks. The collection of environmental data increased demand for applications which are capable of managing and processing large-scale and high-resolution data sets. With the amount and resolution of data sets provided, one of the challenging tasks for organizing and customizing hydrological data sets is delineation of watersheds on demand. Watershed delineation is a process for creating a boundary that represents the contributing area for a specific control point or water outlet, with intent of characterization and analysis of portions of a study area. Although many GIS tools and software for watershed analysis are available on desktop systems, there is a need for web-based and client-side techniques for creating a dynamic and interactive environment for exploring hydrological data. In this project, we demonstrated several watershed delineation techniques on the web with various techniques implemented on the client-side using JavaScript and WebGL, and on the server-side using Python and C++. We also developed a client-side GPGPU (General Purpose Graphical Processing Unit) algorithm to analyze high-resolution terrain data for watershed delineation which allows parallelization using GPU. The web-based real-time analysis of watershed segmentation can be helpful for decision-makers and interested stakeholders while eliminating the need of installing complex software packages and dealing with large-scale data sets. Utilization of the client-side hardware resources also eliminates the need of servers due its crowdsourcing nature. Our goal for future work is to improve other hydrologic analysis methods such as rain flow tracking by adapting presented approaches.
Global Cost and Weight Evaluation of Fuselage Side Panel Design Concepts
NASA Technical Reports Server (NTRS)
Polland, D. R.; Finn, S. R.; Griess, K. H.; Hafenrichter, J. L.; Hanson, C. T.; Ilcewicz, L. B.; Metschan, S. L.; Scholz, D. B.; Smith, P. J.
1997-01-01
This report documents preliminary design trades conducted under NASA contracts NAS1 18889 (Advanced Technology Composite Aircraft Structures, ATCAS) and NAS1-19349 (Task 3, Pathfinder Shell Design) for a subsonic wide body commercial aircraft fuselage side panel section utilizing composite materials. Included in this effort were (1) development of two complete design concepts, (2) generation of cost and weight estimates, (3) identification of technical issues and potential design enhancements, and (4) selection of a single design to be further developed. The first design concept featured an open-section stringer stiffened skin configuration while the second was based on honeycomb core sandwich construction. The trade study cost and weight results were generated from comprehensive assessment of each structural component comprising the fuselage side panel section from detail fabrication through airplane final assembly. Results were obtained in three phases: (1) for the baseline designs, (2) after global optimization of the designs, and (3) the results anticipated after detailed design optimization. A critical assessment of both designs was performed to determine the risk associated with each concept, that is the relative probability of achieving the cost and weight projections. Seven critical technical issues were identified as the first step towards side panel detailed design optimization.
An approach to modeling and optimization of integrated renewable energy system (ires)
NASA Astrophysics Data System (ADS)
Maheshwari, Zeel
The purpose of this study was to cost optimize electrical part of IRES (Integrated Renewable Energy Systems) using HOMER and maximize the utilization of resources using MATLAB programming. IRES is an effective and a viable strategy that can be employed to harness renewable energy resources to energize remote rural areas of developing countries. The resource- need matching, which is the basis for IRES makes it possible to provide energy in an efficient and cost effective manner. Modeling and optimization of IRES for a selected study area makes IRES more advantageous when compared to hybrid concepts. A remote rural area with a population of 700 in 120 households and 450 cattle is considered as an example for cost analysis and optimization. Mathematical models for key components of IRES such as biogas generator, hydropower generator, wind turbine, PV system and battery banks are developed. A discussion of the size of water reservoir required is also presented. Modeling of IRES on the basis of need to resource and resource to need matching is pursued to help in optimum use of resources for the needs. Fixed resources such as biogas and water are used in prioritized order whereas movable resources such as wind and solar can be used simultaneously for different priorities. IRES is cost optimized for electricity demand using HOMER software that is developed by the NREL (National Renewable Energy Laboratory). HOMER optimizes configuration for electrical demand only and does not consider other demands such as biogas for cooking and water for domestic and irrigation purposes. Hence an optimization program based on the need-resource modeling of IRES is performed in MATLAB. Optimization of the utilization of resources for several needs is performed. Results obtained from MATLAB clearly show that the available resources can fulfill the demand of the rural areas. Introduction of IRES in rural communities has many socio-economic implications. It brings about improvement in living environment and community welfare by supplying the basic needs such as biogas for cooking, water for domestic and irrigation purposes and electrical energy for lighting, communication, cold storage, educational and small- scale industrial purposes.
Issues facing the future health care workforce: the importance of demand modelling
Segal, Leonie; Bolton, Tom
2009-01-01
This article examines issues facing the future health care workforce in Australia in light of factors such as population ageing. It has been argued that population ageing in Australia is affecting the supply of health care professionals as the health workforce ages and at the same time increasing the demand for health care services and the health care workforce. However, the picture is not that simple. The health workforce market in Australia is influenced by a wide range of factors; on the demand side by increasing levels of income and wealth, emergence of new technologies, changing disease profiles, changing public health priorities and a focus on the prevention of chronic disease. While a strong correlation is observed between age and use of health care services (and thus health care workforce), this is mediated through illness, as typified by the consistent finding of higher health care costs in the months preceding death. On the supply side, the health workforce is highly influenced by policy drivers; both national policies (eg funded education and training places) and local policies (eg work place-based retention policies). Population ageing and ageing of the health workforce is not a dominant influence. In recent years, the Australian health care workforce has grown in excess of overall workforce growth, despite an ageing health workforce. We also note that current levels of workforce supply compare favourably with many OECD countries. The future of the health workforce will be shaped by a number of complex interacting factors. Market failure, a key feature of the market for health care services which is also observed in the health care labour market – means that imbalances between demand and supply can develop and persist, and suggests a role for health workforce planning to improve efficiency in the health services sector. Current approaches to health workforce planning, especially on the demand side, tend to be highly simplistic. These include historical allocation methods, such as the personnel-to-population ratios which are essentially circular in their rationale rather than evidence-based. This article highlights the importance of evidence-based demand modelling for those seeking to plan for the future Australian health care workforce. A model based on population health status and best practice protocols for health care is briefly outlined. PMID:19422686
Issues facing the future health care workforce: the importance of demand modelling.
Segal, Leonie; Bolton, Tom
2009-05-07
This article examines issues facing the future health care workforce in Australia in light of factors such as population ageing. It has been argued that population ageing in Australia is affecting the supply of health care professionals as the health workforce ages and at the same time increasing the demand for health care services and the health care workforce.However, the picture is not that simple. The health workforce market in Australia is influenced by a wide range of factors; on the demand side by increasing levels of income and wealth, emergence of new technologies, changing disease profiles, changing public health priorities and a focus on the prevention of chronic disease. While a strong correlation is observed between age and use of health care services (and thus health care workforce), this is mediated through illness, as typified by the consistent finding of higher health care costs in the months preceding death.On the supply side, the health workforce is highly influenced by policy drivers; both national policies (eg funded education and training places) and local policies (eg work place-based retention policies). Population ageing and ageing of the health workforce is not a dominant influence. In recent years, the Australian health care workforce has grown in excess of overall workforce growth, despite an ageing health workforce. We also note that current levels of workforce supply compare favourably with many OECD countries. The future of the health workforce will be shaped by a number of complex interacting factors.Market failure, a key feature of the market for health care services which is also observed in the health care labour market - means that imbalances between demand and supply can develop and persist, and suggests a role for health workforce planning to improve efficiency in the health services sector. Current approaches to health workforce planning, especially on the demand side, tend to be highly simplistic. These include historical allocation methods, such as the personnel-to-population ratios which are essentially circular in their rationale rather than evidence-based. This article highlights the importance of evidence-based demand modelling for those seeking to plan for the future Australian health care workforce. A model based on population health status and best practice protocols for health care is briefly outlined.
NASA Astrophysics Data System (ADS)
Izadi, Arman; Kimiagari, Ali mohammad
2014-01-01
Distribution network design as a strategic decision has long-term effect on tactical and operational supply chain management. In this research, the location-allocation problem is studied under demand uncertainty. The purposes of this study were to specify the optimal number and location of distribution centers and to determine the allocation of customer demands to distribution centers. The main feature of this research is solving the model with unknown demand function which is suitable with the real-world problems. To consider the uncertainty, a set of possible scenarios for customer demands is created based on the Monte Carlo simulation. The coefficient of variation of costs is mentioned as a measure of risk and the most stable structure for firm's distribution network is defined based on the concept of robust optimization. The best structure is identified using genetic algorithms and 14% reduction in total supply chain costs is the outcome. Moreover, it imposes the least cost variation created by fluctuation in customer demands (such as epidemic diseases outbreak in some areas of the country) to the logistical system. It is noteworthy that this research is done in one of the largest pharmaceutical distribution firms in Iran.
NASA Astrophysics Data System (ADS)
Izadi, Arman; Kimiagari, Ali Mohammad
2014-05-01
Distribution network design as a strategic decision has long-term effect on tactical and operational supply chain management. In this research, the location-allocation problem is studied under demand uncertainty. The purposes of this study were to specify the optimal number and location of distribution centers and to determine the allocation of customer demands to distribution centers. The main feature of this research is solving the model with unknown demand function which is suitable with the real-world problems. To consider the uncertainty, a set of possible scenarios for customer demands is created based on the Monte Carlo simulation. The coefficient of variation of costs is mentioned as a measure of risk and the most stable structure for firm's distribution network is defined based on the concept of robust optimization. The best structure is identified using genetic algorithms and 14 % reduction in total supply chain costs is the outcome. Moreover, it imposes the least cost variation created by fluctuation in customer demands (such as epidemic diseases outbreak in some areas of the country) to the logistical system. It is noteworthy that this research is done in one of the largest pharmaceutical distribution firms in Iran.
Lerut, J; de Ville de Goyet, J; Donataccio, M; Reding, R; Otte, J B
1994-11-01
Split liver grafting has not gained wide acceptance mainly because of different vascular and biliary technical problems. A new technique of right split liver transplantation is described. The piggyback implantation technique, using wide side-to-side cavocavostomy overcomes problems encountered when sharing the superhepatic vena cava cuff between two livers and obtains optimal drainage of venous allograft outflow, thus avoiding extensive bleeding at the transection margin. This technique was successfully used in two adult recipients. Piggyback transplantation using wide side-to-side cavocavostomy allows easy and safe implantation of the right split liver allograft.
NASA Astrophysics Data System (ADS)
Peviani, Maximo; Alterach, Julio; Danelli, Andrea
2010-05-01
The three years SEE HYDROPOWER project started on June 2009, financed by the South-East Transnational Cooperation Programme (EU), aims to a sustainable exploitation of water concerning hydropower production in SEE countries, looking up to renewable energy sources development, preserving environmental quality and preventing flood risk. Hydropower is the most important renewable resource for energy production in the SEE countries but creates ecological impacts on a local scale. If on one hand, hydroelectric production has to be maintained and likely increased following the demand trend and RES-e Directive, on the other hand, hydropower utilisation often involves severe hydrological changes, damages the connectivity of water bodies and injures river ecosystems. The project gives a strong contribution to the integration between the Water Frame and the RES-e Directives in the involved countries. The SEE HYDROPOWER project promotes the optimal use of water, as multiple natural resources, in order to face the increasing regional electrical-energy demand. Furthermore, SEE HYDROPOWER defines specific needs and test methodologies & tools, in order to help public bodies to take decisions about planning and management of water and hydropower concessions, considering all multi-purposes uses, taking into account the environmental sustainability of natural resources and flooding risks. Investigations is carried on to define common strategies & methods for preserving river with particular concerns to aquatic ecosystems, considering the required Minimum Environmental Flow, macro-habitat quality, migratory fishes and related environmental issues. Other problem addressed by the Project is the contrast between Public Administration and Environmental associations on one side and the Hydropower producers on the other side, for the exploitation of water bodies. Competition between water users (for drinking, irrigation, industrial processes, power generation, etc.) is becoming a serious problem, and there is a strong need of a more accurate planning and management optimization of the resources. The partnership includes a well balance mixing of public administrations, agencies ruling hydropower development, water bodies conservation and scientific institutions having the most advanced technology applied to water management and hydropower generation. Furthermore, a permanent "consultant panel" integrated by target groups representatives from different European countries are involved in key decisions and meetings, that guaranty a concrete regional scale participation. The present work reports the overall strategy of the project and the description of the main informatic tools that are under development and implementation in five pilot regions, located in Italy, Austria, Romania, Slovenia and Greece. Keywords: WFD Directive, RES-e Directive, water multi-purpose uses, renewable energy, small hydropower production, environmental balance, minimum environmental flow, flood protection
Exact one-sided confidence limits for the difference between two correlated proportions.
Lloyd, Chris J; Moldovan, Max V
2007-08-15
We construct exact and optimal one-sided upper and lower confidence bounds for the difference between two probabilities based on matched binary pairs using well-established optimality theory of Buehler. Starting with five different approximate lower and upper limits, we adjust them to have coverage probability exactly equal to the desired nominal level and then compare the resulting exact limits by their mean size. Exact limits based on the signed root likelihood ratio statistic are preferred and recommended for practical use.
Liu, Guo-Tian; Xu, Hong-Guo; Wang, Li-Jun; Li, Shao-Hua
2013-01-01
Background The decline of photosynthesis in plants under low sink demand is well known. Previous studies focused on the relationship between stomatal conductance (g s) and net photosynthetic rate (P n). These studies investigated the effect of changes in Photosystem II (PSII) function on the P n decline under low sink demand. However, little is known about its effects on different limiting steps of electron transport chain in PSII under this condition. Methodology/Principal Finding Two-month-old bean plants were processed by removing pods and flowers (low sink demand). On the 1st day after low sink demand treatment, a decline of P n was accompanied by a decrease in g s and internal-to-ambient CO2 concentration ratio (C i/C a). From the 3rd to 9th day, P n and g s declined continuously while C i/C a ratio remained stable in the treatment. Moreover, these values were lower than that of control. Wk (a parameter reflecting the damage to oxygen evolving complex of the donor side of PSII) values in the treatment were significantly higher than their corresponding control values. However, RCQA (a parameter reflecting the number of active RCs per excited cross-section of PSII) values in the treatment were significantly lower than control from the 5th day. From the 11th to 21st day, P n and g s of the treatment continued to decline and were lower than control. This was accompanied by a decrease of RCQA, and an increase of Wk. Furthermore, the quantum yield parameters φ Po, φ Eo and ψ Eo in the treatment were lower than in control; however, C i/C a values in the treatment gradually increased and were significantly higher than control on the 21st day. Conclusions Stomatal limitation during the early stage, whereas a combination of stomatal and non-stomatal limitation during the middle stage might be responsible for the reduction of P n under low sink demand. Non-stomatal limitation during the late stages after the removal of the sink of roots and pods may also cause P n reduction. The non-stomatal limitation was associated with the inhibition of PSII electron transport chain. Our data suggests that the donor side of PSII was the most sensitive to low sink demand followed by the reaction center of PSII. The acceptor side of PSII may be the least sensitive. PMID:24324626
Integrated thermal and energy management of plug-in hybrid electric vehicles
NASA Astrophysics Data System (ADS)
Shams-Zahraei, Mojtaba; Kouzani, Abbas Z.; Kutter, Steffen; Bäker, Bernard
2012-10-01
In plug-in hybrid electric vehicles (PHEVs), the engine temperature declines due to reduced engine load and extended engine off period. It is proven that the engine efficiency and emissions depend on the engine temperature. Also, temperature influences the vehicle air-conditioner and the cabin heater loads. Particularly, while the engine is cold, the power demand of the cabin heater needs to be provided by the batteries instead of the waste heat of engine coolant. The existing energy management strategies (EMS) of PHEVs focus on the improvement of fuel efficiency based on hot engine characteristics neglecting the effect of temperature on the engine performance and the vehicle power demand. This paper presents a new EMS incorporating an engine thermal management method which derives the global optimal battery charge depletion trajectories. A dynamic programming-based algorithm is developed to enforce the charge depletion boundaries, while optimizing a fuel consumption cost function by controlling the engine power. The optimal control problem formulates the cost function based on two state variables: battery charge and engine internal temperature. Simulation results demonstrate that temperature and the cabin heater/air-conditioner power demand can significantly influence the optimal solution for the EMS, and accordingly fuel efficiency and emissions of PHEVs.
Nguyen, Phuong H; Kim, Sunny S; Nguyen, Tuan T; Tran, Lan M; Hajeebhoy, Nemat; Frongillo, Edward A; Ruel, Marie T; Rawat, Rahul; Menon, Purnima
2016-01-01
Adequate utilization of services is critical to maximize the impact of counselling on infant and young child feeding (IYCF), but little is known about factors affecting utilization. Our study examined supply- and demand-side factors associated with the utilization of IYCF counselling services in Viet Nam. We used survey data from mothers with children <2y (n = 1,008) and health staff (n = 60) from the evaluation of a program that embedded IYCF counseling into the existing government health system. The frequency of never users, one-time users, repeat users, and achievers of the recommended minimum number of visits at health facilities were 45.1%, 13.0%, 28.4% and 13.5%, respectively. Poisson regression showed that demand-generation strategies, especially invitation cards, were the key factors determining one-time use (Prevalence ratio, PR 3.0, 95% CI: 2.2-4.2), repeated use (PR 3.2, 95% CI: 2.4-4.2), and achievement of minimum visits (PR 5.5, 95% CI: 3.6-8.4). Higher maternal education was associated with higher utilization both for one-time and repeated use. Being a farmer, belonging to an ethnic minority, and having a wasted child were associated with greater likelihood of achieving the minimum recommended number of visits, whereas child stunting or illness were not. Distance to health center was a barrier to repeated visits. Among supply-side factors, good counselling skills (PR: 1.3-1.8) was the most important factor associated with any service use, whereas longer employment duration and greater work pressure of health center staff were associated with lower utilization. Population attributable risk estimations showed that an additional 25% of the population would have achieved the minimum number of visits if exposed to three demand-generation strategies, and further increased to 49% if the health staff had good counseling skills and low work pressure. Our study provides evidence that demand-generation strategies are essential to increase utilization of facility-based IYCF counselling services in Viet Nam, and may be relevant for increasing and sustaining use of nutrition services in similar contexts.
Nguyen, Phuong H.; Kim, Sunny S.; Nguyen, Tuan T.; Tran, Lan M.; Hajeebhoy, Nemat; Frongillo, Edward A.; Ruel, Marie T.; Rawat, Rahul; Menon, Purnima
2016-01-01
Adequate utilization of services is critical to maximize the impact of counselling on infant and young child feeding (IYCF), but little is known about factors affecting utilization. Our study examined supply- and demand-side factors associated with the utilization of IYCF counselling services in Viet Nam. We used survey data from mothers with children <2y (n = 1,008) and health staff (n = 60) from the evaluation of a program that embedded IYCF counseling into the existing government health system. The frequency of never users, one-time users, repeat users, and achievers of the recommended minimum number of visits at health facilities were 45.1%, 13.0%, 28.4% and 13.5%, respectively. Poisson regression showed that demand-generation strategies, especially invitation cards, were the key factors determining one-time use (Prevalence ratio, PR 3.0, 95% CI: 2.2–4.2), repeated use (PR 3.2, 95% CI: 2.4–4.2), and achievement of minimum visits (PR 5.5, 95% CI: 3.6–8.4). Higher maternal education was associated with higher utilization both for one-time and repeated use. Being a farmer, belonging to an ethnic minority, and having a wasted child were associated with greater likelihood of achieving the minimum recommended number of visits, whereas child stunting or illness were not. Distance to health center was a barrier to repeated visits. Among supply-side factors, good counselling skills (PR: 1.3–1.8) was the most important factor associated with any service use, whereas longer employment duration and greater work pressure of health center staff were associated with lower utilization. Population attributable risk estimations showed that an additional 25% of the population would have achieved the minimum number of visits if exposed to three demand-generation strategies, and further increased to 49% if the health staff had good counseling skills and low work pressure. Our study provides evidence that demand-generation strategies are essential to increase utilization of facility-based IYCF counselling services in Viet Nam, and may be relevant for increasing and sustaining use of nutrition services in similar contexts. PMID:26962856
Two-phase strategy of controlling motor coordination determined by task performance optimality.
Shimansky, Yury P; Rand, Miya K
2013-02-01
A quantitative model of optimal coordination between hand transport and grip aperture has been derived in our previous studies of reach-to-grasp movements without utilizing explicit knowledge of the optimality criterion or motor plant dynamics. The model's utility for experimental data analysis has been demonstrated. Here we show how to generalize this model for a broad class of reaching-type, goal-directed movements. The model allows for measuring the variability of motor coordination and studying its dependence on movement phase. The experimentally found characteristics of that dependence imply that execution noise is low and does not affect motor coordination significantly. From those characteristics it is inferred that the cost of neural computations required for information acquisition and processing is included in the criterion of task performance optimality as a function of precision demand for state estimation and decision making. The precision demand is an additional optimized control variable that regulates the amount of neurocomputational resources activated dynamically. It is shown that an optimal control strategy in this case comprises two different phases. During the initial phase, the cost of neural computations is significantly reduced at the expense of reducing the demand for their precision, which results in speed-accuracy tradeoff violation and significant inter-trial variability of motor coordination. During the final phase, neural computations and thus motor coordination are considerably more precise to reduce the cost of errors in making a contact with the target object. The generality of the optimal coordination model and the two-phase control strategy is illustrated on several diverse examples.
City of San Antonio, Texas Better Buildings Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meyer, Liza C.; Hammer, Mary C.
2014-06-30
The San Antonio Better Buildings Program is a unified single-point-of-service energy efficiency delivery mechanism targeting residential, commercial, institutional, industrial and public buildings. This comprehensive and replicable energy efficiency program is designed to be an effective demand side management initiative to provide a seamless process for program participants to have turn-key access to expert analysis, support and incentives to improve the performance of their in-place energy using systems, while reducing electrical energy use and demand.
NASA Astrophysics Data System (ADS)
Kaune, Alexander; López, Patricia; Werner, Micha; de Fraiture, Charlotte
2017-04-01
Hydrological information on water availability and demand is vital for sound water allocation decisions in irrigation districts, particularly in times of water scarcity. However, sub-optimal water allocation decisions are often taken with incomplete hydrological information, which may lead to agricultural production loss. In this study we evaluate the benefit of additional hydrological information from earth observations and reanalysis data in supporting decisions in irrigation districts. Current water allocation decisions were emulated through heuristic operational rules for water scarce and water abundant conditions in the selected irrigation districts. The Dynamic Water Balance Model based on the Budyko framework was forced with precipitation datasets from interpolated ground measurements, remote sensing and reanalysis data, to determine the water availability for irrigation. Irrigation demands were estimated based on estimates of potential evapotranspiration and coefficient for crops grown, adjusted with the interpolated precipitation data. Decisions made using both current and additional hydrological information were evaluated through the rate at which sub-optimal decisions were made. The decisions made using an amended set of decision rules that benefit from additional information on demand in the districts were also evaluated. Results show that sub-optimal decisions can be reduced in the planning phase through improved estimates of water availability. Where there are reliable observations of water availability through gauging stations, the benefit of the improved precipitation data is found in the improved estimates of demand, equally leading to a reduction of sub-optimal decisions.
Rassi, Christian; Graham, Kirstie; King, Rebecca; Ssekitooleko, James; Mufubenga, Patrobas; Gudoi, Sam Siduda
2016-11-04
To prevent malaria infection during pregnancy in endemic areas in Africa, the World Health Organization recommends the administration of intermittent preventive treatment in pregnancy (IPTp) as part of the focused antenatal care package. However, IPTp uptake in most countries remains low despite generally high antenatal care coverage and increased efforts by governments to address known bottlenecks such as drug stock-outs. The study explored factors that continue to impede uptake of IPTp among women who attend antenatal care. This paper focuses on demand-side barriers with regard to accessibility, affordability and acceptability. The research was conducted in 2013/2014 and involved 46 in-depth interviews with four types of respondents: (i) seven district health officials; (ii) 15 health workers; (iii) 19 women who attended antenatal care; (iv) five opinion leaders. Interviews were conducted in Eastern and West Nile regions of Uganda. Data was analysed by thematic analysis. District health officials and health workers cited a range of barriers relating to knowledge and attitudes among pregnant women, including lack of awareness of pregnancy-related health risks, a tendency to initiate antenatal care late, reluctance to take medication and concerns about side effects of IPTp. However, women and opinion leaders expressed very positive views of antenatal care and IPTp. They also reported that the burden of travel and cost associated with antenatal care attendance was challenging, but did not keep them from accessing a service they perceived as beneficial. The role of trust in health workers' expertise was highlighted by all respondents and it was reported that women will typically accept IPTp if encouraged by a health worker. Given the positive views of antenatal care and IPTp, high antenatal care coverage and reported low refusal rates for IPTp, supply-side issues are likely to account for the majority of missed opportunities for the provision of IPTp when women attend antenatal care. However, to increase uptake of IPTp on the demand side, health workers should be encouraged to reassure eligible women that IPTp is safe.
Optimal pricing and marketing planning for deteriorating items.
Moosavi Tabatabaei, Seyed Reza; Sadjadi, Seyed Jafar; Makui, Ahmad
2017-01-01
Optimal pricing and marketing planning plays an essential role in production decisions on deteriorating items. This paper presents a mathematical model for a three-level supply chain, which includes one producer, one distributor and one retailer. The proposed study considers the production of a deteriorating item where demand is influenced by price, marketing expenditure, quality of product and after-sales service expenditures. The proposed model is formulated as a geometric programming with 5 degrees of difficulty and the problem is solved using the recent advances in optimization techniques. The study is supported by several numerical examples and sensitivity analysis is performed to analyze the effects of the changes in different parameters on the optimal solution. The preliminary results indicate that with the change in parameters influencing on demand, inventory holding, inventory deteriorating and set-up costs change and also significantly affect total revenue.
Resource Optimization Scheme for Multimedia-Enabled Wireless Mesh Networks
Ali, Amjad; Ahmed, Muhammad Ejaz; Piran, Md. Jalil; Suh, Doug Young
2014-01-01
Wireless mesh networking is a promising technology that can support numerous multimedia applications. Multimedia applications have stringent quality of service (QoS) requirements, i.e., bandwidth, delay, jitter, and packet loss ratio. Enabling such QoS-demanding applications over wireless mesh networks (WMNs) require QoS provisioning routing protocols that lead to the network resource underutilization problem. Moreover, random topology deployment leads to have some unused network resources. Therefore, resource optimization is one of the most critical design issues in multi-hop, multi-radio WMNs enabled with multimedia applications. Resource optimization has been studied extensively in the literature for wireless Ad Hoc and sensor networks, but existing studies have not considered resource underutilization issues caused by QoS provisioning routing and random topology deployment. Finding a QoS-provisioned path in wireless mesh networks is an NP complete problem. In this paper, we propose a novel Integer Linear Programming (ILP) optimization model to reconstruct the optimal connected mesh backbone topology with a minimum number of links and relay nodes which satisfies the given end-to-end QoS demands for multimedia traffic and identification of extra resources, while maintaining redundancy. We further propose a polynomial time heuristic algorithm called Link and Node Removal Considering Residual Capacity and Traffic Demands (LNR-RCTD). Simulation studies prove that our heuristic algorithm provides near-optimal results and saves about 20% of resources from being wasted by QoS provisioning routing and random topology deployment. PMID:25111241
Resource optimization scheme for multimedia-enabled wireless mesh networks.
Ali, Amjad; Ahmed, Muhammad Ejaz; Piran, Md Jalil; Suh, Doug Young
2014-08-08
Wireless mesh networking is a promising technology that can support numerous multimedia applications. Multimedia applications have stringent quality of service (QoS) requirements, i.e., bandwidth, delay, jitter, and packet loss ratio. Enabling such QoS-demanding applications over wireless mesh networks (WMNs) require QoS provisioning routing protocols that lead to the network resource underutilization problem. Moreover, random topology deployment leads to have some unused network resources. Therefore, resource optimization is one of the most critical design issues in multi-hop, multi-radio WMNs enabled with multimedia applications. Resource optimization has been studied extensively in the literature for wireless Ad Hoc and sensor networks, but existing studies have not considered resource underutilization issues caused by QoS provisioning routing and random topology deployment. Finding a QoS-provisioned path in wireless mesh networks is an NP complete problem. In this paper, we propose a novel Integer Linear Programming (ILP) optimization model to reconstruct the optimal connected mesh backbone topology with a minimum number of links and relay nodes which satisfies the given end-to-end QoS demands for multimedia traffic and identification of extra resources, while maintaining redundancy. We further propose a polynomial time heuristic algorithm called Link and Node Removal Considering Residual Capacity and Traffic Demands (LNR-RCTD). Simulation studies prove that our heuristic algorithm provides near-optimal results and saves about 20% of resources from being wasted by QoS provisioning routing and random topology deployment.
Optometric supply and demand in Australia: 2011-2036.
Healy, Ernest; Kiely, Patricia M; Arunachalam, Dharma
2015-05-01
The effective size of the optometric workforce is dependent on graduate numbers, retention rates and immigration and is influenced by age, gender and working hours of optometrists. This paper presents modelling results of the relationship between the projected Australian optometric workforce and projected demand for optometric services for the period 2011 to 2036. Nine hypothetical optometric supply-side and demand-side scenarios are presented. Data from the Australian Bureau of Statistics on age and gender of people listing optometry as their major qualification in the 2011 census were projected over a 25-year period, accounting for factors such as concordance with Health Workforce Australia figures for registered optometrists in Australia in 2011, ageing, attrition, hours worked, new graduates and immigration. Data were compared to the numbers of optometrists calculated as necessary to meet the demand for services of the Australian population to 2036 using nine different scenarios. It was estimated that there would be a surplus of over 1,200 equivalent full-time optometrists (EFTO) in 2036 for the highest service demand scenario of 13.8 million Medicare services, where 21 hours of a 38-hour week per EFTO were allowed for the provision of optometric services under Medicare. Substantial surpluses were predicted in all states and territories except Queensland, Tasmania and the Northern Territory where predicted supply was within six EFTO of predicted demand. Projections using current weightings for mortality, attrition, proportion of optometrists in active practice, working hours, immigration, new graduates and 21 hours per EFTO per week available for Medicare services indicate that in 2036, there will be excess optometrists in relation to projected demand for services, if service utilisation is maintained at current levels or increased by 10 or 20 per cent. Substantially greater excesses result if each EFTO has 28 or 35 hours per week available for Medicare services. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.
NASA Technical Reports Server (NTRS)
1978-01-01
Areas are examined relating to the design, development and implementation of a satellite power system (SPS): an analysis of the effect of energy R&D programs in general and SPS in particular on optimal fossil fuel consumption patterns, a study of alternative uses of SPS technologies, and a study of the electric power market penetration potential for SPS. It is shown that a credible program of R&D on long-range energy alternatives leads to lower optimal prices for fossil fuels, resulting in large short-term benefits accruing to the specific program elements. Several alternative uses of SPS technologies were identified; however the markets for these technologies are generally quite diffuse and difficult to assess. The notable exception is solar array technology which has, potentially, a very large non-SPS market. It is shown that the market for SPS units derives from two components of demand: the demand created by growth in the electrical energy demand which leads to an increased demand for baseload generating capacity, and a demand created by the need to replace retiring capacity.
NASA Astrophysics Data System (ADS)
Tyralis, Hristos; Karakatsanis, Georgios; Tzouka, Katerina; Mamassis, Nikos
2015-04-01
The Greek electricity system is examined for the period 2002-2014. The demand load data are analysed at various time scales (hourly, daily, seasonal and annual) and they are related to the mean daily temperature and the gross domestic product (GDP) of Greece for the same time period. The prediction of energy demand, a product of the Greek Independent Power Transmission Operator, is also compared with the demand load. Interesting results about the change of the electricity demand scheme after the year 2010 are derived. This change is related to the decrease of the GDP, during the period 2010-2014. The results of the analysis will be used in the development of an energy forecasting system which will be a part of a framework for optimal planning of a large-scale hybrid renewable energy system in which hydropower plays the dominant role. Acknowledgement: This research was funded by the Greek General Secretariat for Research and Technology through the research project Combined REnewable Systems for Sustainable ENergy DevelOpment (CRESSENDO; grant number 5145)
A historical analysis of natural gas demand
NASA Astrophysics Data System (ADS)
Dalbec, Nathan Richard
This thesis analyzes demand in the US energy market for natural gas, oil, and coal over the period of 1918-2013 and examines their price relationship over the period of 2007-2013. Diagnostic tests for time series were used; Augmented Dickey-Fuller, Kwiatkowski-Phillips-Schmidt-Shin, Johansen cointegration, Granger Causality and weak exogeneity tests. Directed acyclic graphs were used as a complimentary test for endogeneity. Due to the varied results in determining endogeneity, a seemingly unrelated regression model was used which assumes all right hand side variables in the three demand equations were exogenous. A number of factors were significant in determining demand for natural gas including its own price, lagged demand, a number of structural break dummies, and trend, while oil indicate some substitutability with natural gas. An error correction model was used to examine the price relationships. Natural gas price was found not to have a significant cointegrating vector.
Bam, L; McLaren, Z M; Coetzee, E; von Leipzig, K H
2017-10-01
The under-performance of supply chains presents a significant hindrance to disease control in developing countries. Stock-outs of essential medicines lead to treatment interruption which can force changes in patient drug regimens, drive drug resistance and increase mortality. This study is one of few to quantitatively evaluate the effectiveness of supply chain policies in reducing shortages and costs. This study develops a systems dynamics simulation model of the downstream supply chain for amikacin, a second-line tuberculosis drug using 10 years of South African data. We evaluate current supply chain performance in terms of reliability, responsiveness and agility, following the widely-used Supply Chain Operation Reference framework. We simulate 141 scenarios that represent different combinations of supplier characteristics, inventory management strategies and demand forecasting methods to identify the Pareto optimal set of management policies that jointly minimize the number of shortages and total cost. Despite long supplier lead times and unpredictable demand, the amikacin supply chain is 98% reliable and agile enough to accommodate a 20% increase in demand without a shortage. However, this is accomplished by overstocking amikacin by 167%, which incurs high holding costs. The responsiveness of suppliers is low: only 57% of orders are delivered to the central provincial drug depot within one month. We identify three Pareto optimal safety stock management policies. Short supplier lead time can produce Pareto optimal outcomes even in the absence of other optimal policies. This study produces concrete, actionable guidelines to cost-effectively reduce stock-outs by implementing optimal supply chain policies. Preferentially selecting drug suppliers with short lead times accommodates unexpected changes in demand. Optimal supply chain management should be an essential component of national policy to reduce the mortality rate. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Rand, Miya K; Shimansky, Yury P
2013-03-01
A quantitative model of optimal transport-aperture coordination (TAC) during reach-to-grasp movements has been developed in our previous studies. The utilization of that model for data analysis allowed, for the first time, to examine the phase dependence of the precision demand specified by the CNS for neurocomputational information processing during an ongoing movement. It was shown that the CNS utilizes a two-phase strategy for movement control. That strategy consists of reducing the precision demand for neural computations during the initial phase, which decreases the cost of information processing at the expense of lower extent of control optimality. To successfully grasp the target object, the CNS increases precision demand during the final phase, resulting in higher extent of control optimality. In the present study, we generalized the model of optimal TAC to a model of optimal coordination between X and Y components of point-to-point planar movements (XYC). We investigated whether the CNS uses the two-phase control strategy for controlling those movements, and how the strategy parameters depend on the prescribed movement speed, movement amplitude and the size of the target area. The results indeed revealed a substantial similarity between the CNS's regulation of TAC and XYC. First, the variability of XYC within individual trials was minimal, meaning that execution noise during the movement was insignificant. Second, the inter-trial variability of XYC was considerable during the majority of the movement time, meaning that the precision demand for information processing was lowered, which is characteristic for the initial phase. That variability significantly decreased, indicating higher extent of control optimality, during the shorter final movement phase. The final phase was the longest (shortest) under the most (least) challenging combination of speed and accuracy requirements, fully consistent with the concept of the two-phase control strategy. This paper further discussed the relationship between motor variability and XYC variability.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., Demand Side Variability, and Network Variability studies, including input data, processing programs, and... should include the product or product groups carried under each listed contract; (k) Spreadsheets and...
Demand management and case management: a conservation strategy.
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.
Lin, Yu-Hsiu; Hu, Yu-Chen
2018-04-27
The emergence of smart Internet of Things (IoT) devices has highly favored the realization of smart homes in a down-stream sector of a smart grid. The underlying objective of Demand Response (DR) schemes is to actively engage customers to modify their energy consumption on domestic appliances in response to pricing signals. Domestic appliance scheduling is widely accepted as an effective mechanism to manage domestic energy consumption intelligently. Besides, to residential customers for DR implementation, maintaining a balance between energy consumption cost and users’ comfort satisfaction is a challenge. Hence, in this paper, a constrained Particle Swarm Optimization (PSO)-based residential consumer-centric load-scheduling method is proposed. The method can be further featured with edge computing. In contrast with cloud computing, edge computing—a method of optimizing cloud computing technologies by driving computing capabilities at the IoT edge of the Internet as one of the emerging trends in engineering technology—addresses bandwidth-intensive contents and latency-sensitive applications required among sensors and central data centers through data analytics at or near the source of data. A non-intrusive load-monitoring technique proposed previously is utilized to automatic determination of physical characteristics of power-intensive home appliances from users’ life patterns. The swarm intelligence, constrained PSO, is used to minimize the energy consumption cost while considering users’ comfort satisfaction for DR implementation. The residential consumer-centric load-scheduling method proposed in this paper is evaluated under real-time pricing with inclining block rates and is demonstrated in a case study. The experimentation reported in this paper shows the proposed residential consumer-centric load-scheduling method can re-shape loads by home appliances in response to DR signals. Moreover, a phenomenal reduction in peak power consumption is achieved by 13.97%.
Is health care a luxury or a necessity or both? Evidence from Turkey.
Yavuz, Nilgun Cil; Yilanci, Veli; Ozturk, Zehra Ayca
2013-02-01
This study investigates the effect of per capita income on per capita health expenditures in Turkey over the period 1975-2007 by using ARDL bounds test approach to the cointegration considering both demand and supply side variables. Since we reject the null hypothesis that there is no cointegration among the series, we estimate long run and short run elasticities. The results show that while income has no effect on health expenditures in the long run, it is a necessity good in the short run that is a 1% increase in per capita income creates an 0.75% increase in per capita health expenditures. On the other hand, by examining the coefficient of demand and supply side variables, we found that average length of stay and number of physicians has negative effect, percentage of older people has positive effect and infant mortality rate has no effect on health expenditures in both short and long runs.
Demand-side management: Why ratemaking should`nt control tax policy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haney, J.D.
1995-01-01
As utilities spend money on demand-side management (DSM) programs, they usually deduct their costs currently as ordinary and necessary business expenses. However, state regulators may force deferral of DSM costs for ratemaking purposes, with possible consequences on tax returns. When regulators defer DSM costs, the Internal Revenue Service (IRS) has offered several theories to challenge current tax deductions. One theory requires capitilization instead of a current deduction if regulators include the DSM cost in rate base and provide for a rate of return on the balance. The IRS explained this theory two years ago in a White Paper on conservationmore » expenses: The direct relationship between a rate of return allowed by the Regulator for conservation expenditures allowed in rate base and future profits establishes a prima facie case for capitalization under the future benefit standard. The authors believe that IRS policy should not be linked to ratemaking decisions.« less
A demand-side view of risk adjustment.
Feldman, R; Dowd, B E; Maciejewski, M
2001-01-01
This paper analyzes the efficient allocation of consumers to health plans. Specifically, we address the question of why employers that offer multiple health plans often make larger contributions to the premiums of the high-cost plans. Our perspective is that the subsidy for high-cost plans represents a form of demand-side risk adjustment that improves efficiency. Without such subsidies (and in the absence of formal risk adjustment), too few employees would choose the high-cost plans preferred by high-risk workers. We test the theory by estimating a model of the employer premium subsidy, using data from a survey of large public employers in 1994. Our empirical analysis shows that employers are more likely to subsidize high-cost plans when the benefits of risk adjustment are greater. The findings suggest that the premium subsidy can accomplish some of the benefits of formal risk adjustment.
Demand-side management glossary
DOE Office of Scientific and Technical Information (OSTI.GOV)
Isaksen, L.; Ignelzi, P.C.
1992-10-01
Demand-side management (DSM) plays an increasingly important role in helping utilities meet capacity needs while addressing important customer service issues. In implementing utility-specific programs, however, DSM professionals have created an entire vocabulary of words and phrases that are often used and interpreted in very different ways by people with similar utility planning backgrounds. Such inconsistent terminology can hamper the very communication DSM seeks to support. Thus, this report-the first of its kind-presents a glossary of DSM terms, grouped under five major categories: (1) utility systems, (2) programs and techniques, (3) costs, revenues, and rates, (4) modeling and analysis, and (5)more » marketing. An index facilitates the rapid search for key words. This glossary together with a complimentary report entitled, Electric Utility DSM Programs: Terminology and Reporting Formats attempts to define some of the most common terms used in DSM today.« less
Demand-side management glossary. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Isaksen, L.; Ignelzi, P.C.
1992-10-01
Demand-side management (DSM) plays an increasingly important role in helping utilities meet capacity needs while addressing important customer service issues. In implementing utility-specific programs, however, DSM professionals have created an entire vocabulary of words and phrases that are often used and interpreted in very different ways by people with similar utility planning backgrounds. Such inconsistent terminology can hamper the very communication DSM seeks to support. Thus, this report-the first of its kind-presents a glossary of DSM terms, grouped under five major categories: (1) utility systems, (2) programs and techniques, (3) costs, revenues, and rates, (4) modeling and analysis, and (5)more » marketing. An index facilitates the rapid search for key words. This glossary together with a complimentary report entitled, Electric Utility DSM Programs: Terminology and Reporting Formats attempts to define some of the most common terms used in DSM today.« less
MULTI-SCALE MODELING AND APPROXIMATION ASSISTED OPTIMIZATION OF BARE TUBE HEAT EXCHANGERS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bacellar, Daniel; Ling, Jiazhen; Aute, Vikrant
2014-01-01
Air-to-refrigerant heat exchangers are very common in air-conditioning, heat pump and refrigeration applications. In these heat exchangers, there is a great benefit in terms of size, weight, refrigerant charge and heat transfer coefficient, by moving from conventional channel sizes (~ 9mm) to smaller channel sizes (< 5mm). This work investigates new designs for air-to-refrigerant heat exchangers with tube outer diameter ranging from 0.5 to 2.0mm. The goal of this research is to develop and optimize the design of these heat exchangers and compare their performance with existing state of the art designs. The air-side performance of various tube bundle configurationsmore » are analyzed using a Parallel Parameterized CFD (PPCFD) technique. PPCFD allows for fast-parametric CFD analyses of various geometries with topology change. Approximation techniques drastically reduce the number of CFD evaluations required during optimization. Maximum Entropy Design method is used for sampling and Kriging method is used for metamodeling. Metamodels are developed for the air-side heat transfer coefficients and pressure drop as a function of tube-bundle dimensions and air velocity. The metamodels are then integrated with an air-to-refrigerant heat exchanger design code. This integration allows a multi-scale analysis of air-side performance heat exchangers including air-to-refrigerant heat transfer and phase change. Overall optimization is carried out using a multi-objective genetic algorithm. The optimal designs found can exhibit 50 percent size reduction, 75 percent decrease in air side pressure drop and doubled air heat transfer coefficients compared to a high performance compact micro channel heat exchanger with same capacity and flow rates.« less
Stasche, Norbert
2006-01-01
Positive airway pressure (PAP) is the therapy of choice for most sleep-related breathing disorders (SRBD). A variety of PAP devices using positive airway pressure (CPAP, BiPAP, APAP, ASV) must be carefully considered before application. This overview aims to provide criteria for choosing the optimal PAP device according to severity and type of sleep-related breathing disorder. In addition, the range of therapeutic applications, constraints and side effects as well as alternative methods to PAP will be discussed. This review is based on an analysis of current literature and clinical experience. The data is presented from an ENT-sleep-laboratory perspective and is designed to help the ENT practitioner initiate treatment and provide support. Different titration methods, current devices and possible applications will be described. In addition to constant pressure devices (CPAP), most commonly used for symptomatic obstructive sleep apnoea (OSA) without complicating conditions, BiPAP models will be introduced. These allow two different positive pressure settings and are thus especially suitable for patients with cardiopulmonary diseases or patients with pressure intolerance, increasing compliance in this subgroup considerably. Compliance can also be increased in patients during first night of therapy, patients with highly variable pressure demands or position-dependent OSA, by using self-regulating Auto-adjust PAP devices (Automatic positive airway pressure, APAP). Patients with Cheyne-Stokes breathing, a subtype of central sleep apnoea, benefit from adaptive servo-ventilation (ASV), which analyzes breathing patterns continually and adjusts the actual ventilation pressure accordingly. This not only reduces daytime sleepiness, but can also influence heart disease positively. Therapy with positive airway pressure is very effective in eliminating obstruction-related sleep diseases and symptoms. However, because therapy is generally applied for life, the optimal PAP device must be carefully selected, taking into account side effects that influence compliance. PMID:22073075
Dynamic, stochastic models for congestion pricing and congestion securities.
DOT National Transportation Integrated Search
2010-12-01
This research considers congestion pricing under demand uncertainty. In particular, a robust optimization (RO) approach is applied to optimal congestion pricing problems under user equilibrium. A mathematical model is developed and an analysis perfor...
Immigration and earnings inequality in America's new small-town destinations.
Hyde, Allen; Pais, Jeremy; Wallace, Michael
2015-01-01
Research on the relationship between immigrant population concentration and earnings inequality is divided between two perspectives. Supply-side arguments maintain that areas attracting large numbers of immigrants experience minimal wage growth at the bottom of the earnings distribution, which increases local levels of earnings inequality. Demand-side arguments contend that industrial restructuring reduces the pay of manual labor regardless of, and even prior to, the arrival of foreign-born workers. Adjudicating between these two perspectives is hindered by issues of potential endogeneity, which confound attempts to independently assess the effects of immigration on inequality or vice versa using OLS regression. We consider a third perspective called the reciprocal effects hypothesis which contends that immigrant concentration and earnings inequality emerge together through a mutually reinforcing feedback process. We explore this question in America's "new small-town destinations" using data from U.S. micropolitan statistical areas. We use three-stage least squares estimation to address the endogeneity problem and to test these three hypotheses. While we find support for both the supply- and demand-side perspectives, the results are best explained by the reciprocal effects hypothesis. Copyright © 2014 Elsevier Inc. All rights reserved.
Zhou, Zhongliang; Gao, Jianmin; Xue, Qinxiang; Yang, Xiaowei; Yan, Ju'e
2009-07-01
To solve the problem of 'Kan bing nan, kan bing gui' (medical treatment is difficult to access and expensive), a Harvard-led research team implemented a community-based health insurance scheme known as Rural Mutual Health Care (RMHC) in Chinese rural areas from 2004 to 2006. Two major policies adopted by RMHC included insurance coverage of outpatient services (demand-side policy) and drug policy (supply-side policy). This paper focuses on the effects of these two policies on outpatient service utilization in Chinese village clinics. The data used in this study are from 3-year household follow-up surveys. A generalized negative binomial regression model and a Heckman selection model were constructed using panel data from 2005 to 2007. The results indicate that the price elasticities of demand for outpatient visits and per-visit outpatient expenses were -1.5 and -0.553, respectively. After implementing the supply-side policy, outpatient visits and per-visit outpatient expenses decreased by 94.7 and 55.9%, respectively, controlling for insurance coverage. These findings can be used to make recommendations to the Chinese government on improving the health care system.
Optimal design of work zone median crossovers.
DOT National Transportation Integrated Search
2010-09-01
The use of temporary median crossovers in work zones allows for the closure of one side of a multi-lane roadway while : maintaining two-way traffic on the opposite side. This process provides the ability for construction and maintenance crews : to co...
A novel microgrid demand-side management system for manufacturing facilities
NASA Astrophysics Data System (ADS)
Harper, Terance J.
Thirty-one percent of annual energy consumption in the United States occurs within the industrial sector, where manufacturing processes account for the largest amount of energy consumption and carbon emissions. For this reason, energy efficiency in manufacturing facilities is increasingly important for reducing operating costs and improving profits. Using microgrids to generate local sustainable power should reduce energy consumption from the main utility grid along with energy costs and carbon emissions. Also, microgrids have the potential to serve as reliable energy generators in international locations where the utility grid is often unstable. For this research, a manufacturing process that had approximately 20 kW of peak demand was matched with a solar photovoltaic array that had a peak output of approximately 3 KW. An innovative Demand-Side Management (DSM) strategy was developed to manage the process loads as part of this smart microgrid system. The DSM algorithm managed the intermittent nature of the microgrid and the instantaneous demand of the manufacturing process. The control algorithm required three input signals; one from the microgrid indicating the availability of renewable energy, another from the manufacturing process indicating energy use as a percent of peak production, and historical data for renewable sources and facility demand. Based on these inputs the algorithm had three modes of operation: normal (business as usual), curtailment (shutting off non-critical loads), and energy storage. The results show that a real-time management of a manufacturing process with a microgrid will reduce electrical consumption and peak demand. The renewable energy system for this research was rated to provide up to 13% of the total manufacturing capacity. With actively managing the process loads with the DSM program alone, electrical consumption from the utility grid was reduced by 17% on average. An additional 24% reduction was accomplished when the microgrid and DSM program was enabled together, resulting in a total reduction of 37%. On average, peak demand was reduced by 6%, but due to the intermittency of the renewable source and the billing structure for peak demand, only a 1% reduction was obtained. During a billing period, it only takes one day when solar irradiance is poor to affect the demand reduction capabilities. To achieve further demand reduction, energy storage should be introduced and integrated.
A generic hydroeconomic model to assess future water scarcity
NASA Astrophysics Data System (ADS)
Neverre, Noémie; Dumas, Patrice
2015-04-01
We developed a generic hydroeconomic model able to confront future water supply and demand on a large scale, taking into account man-made reservoirs. The assessment is done at the scale of river basins, using only globally available data; the methodology can thus be generalized. On the supply side, we evaluate the impacts of climate change on water resources. The available quantity of water at each site is computed using the following information: runoff is taken from the outputs of CNRM climate model (Dubois et al., 2010), reservoirs are located using Aquastat, and the sub-basin flow-accumulation area of each reservoir is determined based on a Digital Elevation Model (HYDRO1k). On the demand side, agricultural and domestic demands are projected in terms of both quantity and economic value. For the agricultural sector, globally available data on irrigated areas and crops are combined in order to determine irrigated crops localization. Then, crops irrigation requirements are computed for the different stages of the growing season using Allen (1998) method with Hargreaves potential evapotranspiration. Irrigation water economic value is based on a yield comparison approach between rainfed and irrigated crops. Potential irrigated and rainfed yields are taken from LPJmL (Blondeau et al., 2007), or from FAOSTAT by making simple assumptions on yield ratios. For the domestic sector, we project the combined effects of demographic growth, economic development and water cost evolution on future demands. The method consists in building three-blocks inverse demand functions where volume limits of the blocks evolve with the level of GDP per capita. The value of water along the demand curve is determined from price-elasticity, price and demand data from the literature, using the point-expansion method, and from water costs data. Then projected demands are confronted to future water availability. Operating rules of the reservoirs and water allocation between demands are based on the maximization of water benefits, over time and space. A parameterisation-simulation-optimisation approach is used. This gives a projection of future water scarcity in the different locations and an estimation of the associated direct economic losses from unsatisfied demands. This generic hydroeconomic model can be easily applied to large-scale regions, in particular developing regions where little reliable data is available. We will present an application to Algeria, up to the 2050 horizon.
Optimization of the Upper Surface of Hypersonic Vehicle Based on CFD Analysis
NASA Astrophysics Data System (ADS)
Gao, T. Y.; Cui, K.; Hu, S. C.; Wang, X. P.; Yang, G. W.
2011-09-01
For the hypersonic vehicle, the aerodynamic performance becomes more intensive. Therefore, it is a significant event to optimize the shape of the hypersonic vehicle to achieve the project demands. It is a key technology to promote the performance of the hypersonic vehicle with the method of shape optimization. Based on the existing vehicle, the optimization to the upper surface of the Simplified hypersonic vehicle was done to obtain a shape which suits the project demand. At the cruising condition, the upper surface was parameterized with the B-Spline curve method. The incremental parametric method and the reconstruction technology of the local mesh were applied here. The whole flow field was been calculated and the aerodynamic performance of the craft were obtained by the computational fluid dynamic (CFD) technology. Then the vehicle shape was optimized to achieve the maximum lift-drag ratio at attack angle 3°, 4° and 5°. The results will provide the reference for the practical design.
NASA Astrophysics Data System (ADS)
Mahata, Puspita; Mahata, Gour Chandra; Kumar De, Sujit
2018-03-01
Traditional supply chain inventory modes with trade credit usually only assumed that the up-stream suppliers offered the down-stream retailers a fixed credit period. However, in practice the retailers will also provide a credit period to customers to promote the market competition. In this paper, we formulate an optimal supply chain inventory model under two levels of trade credit policy with default risk consideration. Here, the demand is assumed to be credit-sensitive and increasing function of time. The major objective is to determine the retailer's optimal credit period and cycle time such that the total profit per unit time is maximized. The existence and uniqueness of the optimal solution to the presented model are examined, and an easy method is also shown to find the optimal inventory policies of the considered problem. Finally, numerical examples and sensitive analysis are presented to illustrate the developed model and to provide some managerial insights.
NASA Astrophysics Data System (ADS)
Singh, Trailokyanath; Mishra, Pandit Jagatananda; Pattanayak, Hadibandhu
2017-12-01
In this paper, an economic order quantity (EOQ) inventory model for a deteriorating item is developed with the following characteristics: (i) The demand rate is deterministic and two-staged, i.e., it is constant in first part of the cycle and linear function of time in the second part. (ii) Deterioration rate is time-proportional. (iii) Shortages are not allowed to occur. The optimal cycle time and the optimal order quantity have been derived by minimizing the total average cost. A simple solution procedure is provided to illustrate the proposed model. The article concludes with a numerical example and sensitivity analysis of various parameters as illustrations of the theoretical results.
Configurable product design considering the transition of multi-hierarchical models
NASA Astrophysics Data System (ADS)
Ren, Bin; Qiu, Lemiao; Zhang, Shuyou; Tan, Jianrong; Cheng, Jin
2013-03-01
The current research of configurable product design mainly focuses on how to convert a predefined set of components into a valid set of product structures. With the scale and complexity of configurable products increasing, the interdependencies between customer demands and product structures grow up as well. The result is that existing product structures fails to satisfy the individual customer requirements and hence product variants are needed. This paper is aimed to build a bridge between customer demands and product structures in order to make demand-driven fast response design feasible. First of all, multi-hierarchical models of configurable product design are established with customer demand model, technical requirement model and product structure model. Then, the transition of multi-hierarchical models among customer demand model, technical requirement model and product structure model is solved with fuzzy analytic hierarchy process (FAHP) and the algorithm of multi-level matching. Finally, optimal structure according to the customer demands is obtained with the calculation of Euclidean distance and similarity of some cases. In practice, the configuration design of a clamping unit of injection molding machine successfully performs an optimal search strategy for the product variants with reasonable satisfaction to individual customer demands. The proposed method can automatically generate a configuration design with better alternatives for each product structures, and shorten the time of finding the configuration of a product.
Structural optimization of framed structures using generalized optimality criteria
NASA Technical Reports Server (NTRS)
Kolonay, R. M.; Venkayya, Vipperla B.; Tischler, V. A.; Canfield, R. A.
1989-01-01
The application of a generalized optimality criteria to framed structures is presented. The optimality conditions, Lagrangian multipliers, resizing algorithm, and scaling procedures are all represented as a function of the objective and constraint functions along with their respective gradients. The optimization of two plane frames under multiple loading conditions subject to stress, displacement, generalized stiffness, and side constraints is presented. These results are compared to those found by optimizing the frames using a nonlinear mathematical programming technique.
Mayora, Chrispus; Ekirapa-Kiracho, Elizabeth; Bishai, David; Peters, David H; Okui, Olico; Baine, Sebastian Olikira
2014-01-01
High maternal and infant mortality continue to be major challenges to the attainment of the Millennium Development Goals for many low and middle-income countries. There is now evidence that voucher initiatives can increase access to maternal health services. However, a dearth of knowledge exists on the cost implications of voucher schemes. This paper estimates the incremental costs of a demand and supply side intervention aimed at increasing access to maternal health care services. This costing study was part of a quasi-experimental voucher study conducted in two districts in Eastern Uganda to explore the impact of demand and supply - side incentives on increasing access to maternal health services. The provider's perspective was used and the ingredients approach to costing was employed. Costs were based on market prices as recorded in program records. Total, unit, and incremental costs were calculated. The estimated total financial cost of the intervention for the one year of implementation was US$525,472 (US$1 = 2200UgShs). The major cost drivers included costs for transport vouchers (35.3%), health system strengthening (29.2%) and vouchers for maternal health services (18.2%). The average cost of transport per woman to and from the health facility was US$4.6. The total incremental costs incurred on deliveries (excluding caesarean section) was US$317,157 and US$107,890 for post natal care (PNC). The incremental costs per additional delivery and PNC attendance were US$23.9 and US$7.6 respectively. Subsidizing maternal health care costs through demand and supply - side initiatives may not require significant amounts of resources contrary to what would be expected. With Uganda's Gross Domestic Product (GDP) per capita of US$55` (2012), the incremental cost per additional delivery (US$23.9) represents about 5% of GDP per capita to save a mother and probably her new born. For many low income countries, this may not be affordable, yet reliance on donor funding is often not sustainable. Alternative ways of raising additional resources for health must be explored. These include; encouraging private investments in critical sectors such as rural transport, health service provision; mobilizing households to save financial resources for preparedness, and financial targeting for the most vulnerable.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1994-04-11
This manual is intended primarily for use as a reference by analysts applying the WORLD model to regional studies. It also provides overview information on WORLD features of potential interest to managers and analysts. Broadly, the manual covers WORLD model features in progressively increasing detail. Section 2 provides an overview of the WORLD model, how it has evolved, what its design goals are, what it produces, and where it can be taken with further enhancements. Section 3 reviews model management covering data sources, managing over-optimization, calibration and seasonality, check-points for case construction and common errors. Section 4 describes in detailmore » the WORLD system, including: data and program systems in overview; details of mainframe and PC program control and files;model generation, size management, debugging and error analysis; use with different optimizers; and reporting and results analysis. Section 5 provides a detailed description of every WORLD model data table, covering model controls, case and technology data. Section 6 goes into the details of WORLD matrix structure. It provides an overview, describes how regional definitions are controlled and defines the naming conventions for-all model rows, columns, right-hand sides, and bounds. It also includes a discussion of the formulation of product blending and specifications in WORLD. Several Appendices supplement the main sections.« less
Optimal Operation System of the Integrated District Heating System with Multiple Regional Branches
NASA Astrophysics Data System (ADS)
Kim, Ui Sik; Park, Tae Chang; Kim, Lae-Hyun; Yeo, Yeong Koo
This paper presents an optimal production and distribution management for structural and operational optimization of the integrated district heating system (DHS) with multiple regional branches. A DHS consists of energy suppliers and consumers, district heating pipelines network and heat storage facilities in the covered region. In the optimal management system, production of heat and electric power, regional heat demand, electric power bidding and sales, transport and storage of heat at each regional DHS are taken into account. The optimal management system is formulated as a mixed integer linear programming (MILP) where the objectives is to minimize the overall cost of the integrated DHS while satisfying the operation constraints of heat units and networks as well as fulfilling heating demands from consumers. Piecewise linear formulation of the production cost function and stairwise formulation of the start-up cost function are used to compute nonlinear cost function approximately. Evaluation of the total overall cost is based on weekly operations at each district heat branches. Numerical simulations show the increase of energy efficiency due to the introduction of the present optimal management system.
Autonomous Hybrid Priority Queueing for Scheduling Residential Energy Demands
NASA Astrophysics Data System (ADS)
Kalimullah, I. Q.; Shamroukh, M.; Sahar, N.; Shetty, S.
2017-05-01
The advent of smart grid technologies has opened up opportunities to manage the energy consumption of the users within a residential smart grid system. Demand response management is particularly being employed to reduce the overall load on an electricity network which could in turn reduce outages and electricity costs. The objective of this paper is to develop an intelligible scheduler to optimize the energy available to a micro grid through hybrid queueing algorithm centered around the consumers’ energy demands. This is achieved by shifting certain schedulable load appliances to light load hours. Various factors such as the type of demand, grid load, consumers’ energy usage patterns and preferences are considered while formulating the logical constraints required for the algorithm. The algorithm thus obtained is then implemented in MATLAB workspace to simulate its execution by an Energy Consumption Scheduler (ECS) found within smart meters, which automatically finds the optimal energy consumption schedule tailor made to fit each consumer within the micro grid network.
Empowering leaders optimize working conditions for engagement: a multilevel study.
Tuckey, Michelle R; Bakker, Arnold B; Dollard, Maureen F
2012-01-01
Using a multilevel framework, this study examined the role of empowering leadership at the group level by fire brigade captains in facilitating the individual level motivational processes that underpin work engagement in volunteer firefighters. Anonymous mail surveys were completed by 540 volunteer firefighters from 68 fire brigades and, separately, by 68 brigade captains. As predicted on the basis of the Job Demands-Resources model, increased levels of cognitive demands and cognitive resources partially mediated the relationship between empowering leadership and work engagement. In a three-way Leadership × Demands × Resources interaction, empowering leadership also had the effect of optimizing working conditions for engagement by strengthening the positive effect of a work context in which both cognitive demands and cognitive resources were high. Our findings shed light on a process through which leaders can empower workers and enhance well-being: via their influence on and interaction with the work environment. They also underscore the need to examine work engagement from a multilevel theoretical perspective.
Modeling complexity in engineered infrastructure system: Water distribution network as an example
NASA Astrophysics Data System (ADS)
Zeng, Fang; Li, Xiang; Li, Ke
2017-02-01
The complex topology and adaptive behavior of infrastructure systems are driven by both self-organization of the demand and rigid engineering solutions. Therefore, engineering complex systems requires a method balancing holism and reductionism. To model the growth of water distribution networks, a complex network model was developed following the combination of local optimization rules and engineering considerations. The demand node generation is dynamic and follows the scaling law of urban growth. The proposed model can generate a water distribution network (WDN) similar to reported real-world WDNs on some structural properties. Comparison with different modeling approaches indicates that a realistic demand node distribution and co-evolvement of demand node and network are important for the simulation of real complex networks. The simulation results indicate that the efficiency of water distribution networks is exponentially affected by the urban growth pattern. On the contrary, the improvement of efficiency by engineering optimization is limited and relatively insignificant. The redundancy and robustness, on another aspect, can be significantly improved through engineering methods.
NASA Astrophysics Data System (ADS)
Wu, Zhihui; Chen, Dongyan; Yu, Hui
2016-07-01
In this paper, the problem of the coordination policy is investigated for vendor-managed consignment inventory supply chain subject to consumer return. Here, the market demand is assumed to be affected by promotional effort and consumer return policy. The optimal consignment inventory and the optimal promotional effort level are proposed under the decentralized and centralized decisions. Based on the optimal decision conditions, the markdown allowance-promotional cost-sharing contract is investigated to coordinate the supply chain. Subsequently, the comparison between the two extreme policies shows that full-refund policy dominates the no-return policy when the returning cost and the positive effect of return policy are satisfied certain conditions. Finally, a numerical example is provided to illustrate the impacts of consumer return policy on the coordination contract and optimal profit as well as the effectiveness of the proposed supply chain decision.
NASA Astrophysics Data System (ADS)
Ayadi, Omar; Felfel, Houssem; Masmoudi, Faouzi
2017-07-01
The current manufacturing environment has changed from traditional single-plant to multi-site supply chain where multiple plants are serving customer demands. In this article, a tactical multi-objective, multi-period, multi-product, multi-site supply-chain planning problem is proposed. A corresponding optimization model aiming to simultaneously minimize the total cost, maximize product quality and maximize the customer satisfaction demand level is developed. The proposed solution approach yields to a front of Pareto-optimal solutions that represents the trade-offs among the different objectives. Subsequently, the analytic hierarchy process method is applied to select the best Pareto-optimal solution according to the preferences of the decision maker. The robustness of the solutions and the proposed approach are discussed based on a sensitivity analysis and an application to a real case from the textile and apparel industry.
Optimal pricing and marketing planning for deteriorating items
Moosavi Tabatabaei, Seyed Reza; Sadjadi, Seyed Jafar; Makui, Ahmad
2017-01-01
Optimal pricing and marketing planning plays an essential role in production decisions on deteriorating items. This paper presents a mathematical model for a three-level supply chain, which includes one producer, one distributor and one retailer. The proposed study considers the production of a deteriorating item where demand is influenced by price, marketing expenditure, quality of product and after-sales service expenditures. The proposed model is formulated as a geometric programming with 5 degrees of difficulty and the problem is solved using the recent advances in optimization techniques. The study is supported by several numerical examples and sensitivity analysis is performed to analyze the effects of the changes in different parameters on the optimal solution. The preliminary results indicate that with the change in parameters influencing on demand, inventory holding, inventory deteriorating and set-up costs change and also significantly affect total revenue. PMID:28306750
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.
NASA Astrophysics Data System (ADS)
Wang, S. Y.; Ho, C. C.; Chang, L. C.
2017-12-01
The public use water in Hsinchu are mainly supplied from Baoshan Reservoir, Second Baoshan Reservoir, Yongheshan Reservoir and Longen Weir. However, the increasing water demand, caused by development of the Hsinchu Science and Industrial Park, results in supply stable water getting more difficult. For stabilize water supply in Hsinchu, the study applies long-term and short-term plans to fulfill the water shortage. Developing an efficient methodology to define a cost-effective action portfolio is an important task. Hence, the study develops a novel decision model, the Stochastic Programming with Recourse Decision Model (SPRDM), to estimate a cost-effective action portfolio. The first-stage of SPRDM determine the long-term action portfolio and the portfolio accompany recourse information (the probability for water shortage event). The second-stage of SPRDM optimize the cost-effective action portfolio in response to the recourse information. In order to consider the uncertainty of reservoir sediment and demand growth, the study set 9 scenarios comprise optimistic, most likely, and pessimistic reservoir sediment and demand growth. The results show the optimal action portfolio consist of FengTain Lake and Panlon Weir, Hsinchu Desalination Plant, Domestic and Industrial Water long-term plans, and Emergency Backup Well, Irrigation Water Transference, Preliminary Water Rationing, Advanced Water Rationing and Water Transport from Other Districts short-term plans. The minimum expected cost of optimal action portfolio is NT$1.1002 billion. The results can be used as a reference for decision making because the results have considered the uncertainty of varied hydrology, reservoir sediment, and water demand growth.
A two-objective optimization scheme for high-OSNR and low-power-consuming all-optical networks
NASA Astrophysics Data System (ADS)
Abedifar, Vahid; Mirjalili, Seyed Mohammad; Eshghi, Mohammad
2015-01-01
In all-optical networks the ASE noise of the utilized optical power amplifiers is a major impairment, making the OSNR to be the dominant parameter in QoS. In this paper, a two-objective optimization scheme using Multi-Objective Particle Swarm Optimization (MOPSO) is proposed to reach the maximum OSNR for all channels while the optical power consumed by EDFAs and lasers is minimized. Two scenarios are investigated: Scenario 1 and Scenario 2. The former scenario optimizes the gain values of a predefined number of EDFAs in physical links. The gain values may be different from each other. The latter scenario optimizes the gains value of EDFAs (which is supposed to be identical in each physical link) in addition to the number of EDFAs for each physical link. In both scenarios, the launch powers of the lasers are also taken into account during optimization process. Two novel encoding methods are proposed to uniquely represent the problem solutions. Two virtual demand sets are considered for evaluation of the performance of the proposed optimization scheme. The simulations results are described for both scenarios and both virtual demands.
Impact of climate change on electricity systems and markets
NASA Astrophysics Data System (ADS)
Chandramowli, Shankar N.
Climate change poses a serious threat to human welfare. There is now unequivocal scientific evidence that human actions are the primary cause of climate change. The principal climate forcing factor is the increasing accumulation of atmospheric carbon dioxide (CO2) due to combustion of fossil fuels for transportation and electricity generation. Generation of electricity account for nearly one-third of the greenhouse (GHG) emissions globally (on a CO2-equivalent basis). Any kind of economy-wide mitigation or adaptation effort to climate change must have a prominent focus on the electric power sector. I have developed a capacity expansion model for the power sector called LP-CEM (Linear Programming based Capacity Expansion Model). LP-CEM incorporates both the long-term climate change effects and the state/regional-level macroeconomic trends. This modeling framework is demonstrated for the electric power system in the Northeast region of United States. Some of the methodological advances introduced in this research are: the use of high-resolution temperature projections in a power sector capacity expansion model; the incorporation of changes in sectoral composition of electricity demand over time; the incorporation of the effects of climate change and variability on both the demand and supply-side of power sector using parameters estimated in the literature; and an inter-model coupling link with a macroeconomic model to account for price elasticity of demand and other effects on the broader macro-economy. LP-CEM-type models can be of use to state/regional level policymakers to plan for future mitigation and adaptation measures for the electric power sector. From the simulation runs, it is shown that scenarios with climate change effects and with high economic growth rates have resulted in higher capacity addition, optimal supply costs, wholesale/retail prices and total ratepayers' costs. LP-CEM is also adapted to model the implications of the proposed Clean Power Plan (Section 111 (d)) rules for the U.S. Northeast region. This dissertation applies an analytical model and an optimization model to investigate the implications of co-implementing an emission cap and an RPS policy for this region. A simplified analytical model of LP-CEM is specified and the first order optimality conditions are derived. The results from this analytical model are corroborated by running LP-CEM simulations under different carbon cap and RPS policy assumptions. A combination of these policies is shown to have a long-term beneficial effect for the final ratepayers in the region. This research conceptually explores the future implications of climate change and extreme weather events on the regional electricity market framework. The significant findings from this research and future policy considerations are discussed in the conclusion chapter.
Multistage Stochastic Programming and its Applications in Energy Systems Modeling and Optimization
NASA Astrophysics Data System (ADS)
Golari, Mehdi
Electric energy constitutes one of the most crucial elements to almost every aspect of life of people. The modern electric power systems face several challenges such as efficiency, economics, sustainability, and reliability. Increase in electrical energy demand, distributed generations, integration of uncertain renewable energy resources, and demand side management are among the main underlying reasons of such growing complexity. Additionally, the elements of power systems are often vulnerable to failures because of many reasons, such as system limits, weak conditions, unexpected events, hidden failures, human errors, terrorist attacks, and natural disasters. One common factor complicating the operation of electrical power systems is the underlying uncertainties from the demands, supplies and failures of system components. Stochastic programming provides a mathematical framework for decision making under uncertainty. It enables a decision maker to incorporate some knowledge of the intrinsic uncertainty into the decision making process. In this dissertation, we focus on application of two-stage and multistage stochastic programming approaches to electric energy systems modeling and optimization. Particularly, we develop models and algorithms addressing the sustainability and reliability issues in power systems. First, we consider how to improve the reliability of power systems under severe failures or contingencies prone to cascading blackouts by so called islanding operations. We present a two-stage stochastic mixed-integer model to find optimal islanding operations as a powerful preventive action against cascading failures in case of extreme contingencies. Further, we study the properties of this problem and propose efficient solution methods to solve this problem for large-scale power systems. We present the numerical results showing the effectiveness of the model and investigate the performance of the solution methods. Next, we address the sustainability issue considering the integration of renewable energy resources into production planning of energy-intensive manufacturing industries. Recently, a growing number of manufacturing companies are considering renewable energies to meet their energy requirements to move towards green manufacturing as well as decreasing their energy costs. However, the intermittent nature of renewable energies imposes several difficulties in long term planning of how to efficiently exploit renewables. In this study, we propose a scheme for manufacturing companies to use onsite and grid renewable energies provided by their own investments and energy utilities as well as conventional grid energy to satisfy their energy requirements. We propose a multistage stochastic programming model and study an efficient solution method to solve this problem. We examine the proposed framework on a test case simulated based on a real-world semiconductor company. Moreover, we evaluate long-term profitability of such scheme via so called value of multistage stochastic programming.
Sasaki, Satoshi; Comber, Alexis J; Suzuki, Hiroshi; Brunsdon, Chris
2010-01-28
Ambulance response time is a crucial factor in patient survival. The number of emergency cases (EMS cases) requiring an ambulance is increasing due to changes in population demographics. This is decreasing ambulance response times to the emergency scene. This paper predicts EMS cases for 5-year intervals from 2020, to 2050 by correlating current EMS cases with demographic factors at the level of the census area and predicted population changes. It then applies a modified grouping genetic algorithm to compare current and future optimal locations and numbers of ambulances. Sets of potential locations were evaluated in terms of the (current and predicted) EMS case distances to those locations. Future EMS demands were predicted to increase by 2030 using the model (R2 = 0.71). The optimal locations of ambulances based on future EMS cases were compared with current locations and with optimal locations modelled on current EMS case data. Optimising the location of ambulance stations locations reduced the average response times by 57 seconds. Current and predicted future EMS demand at modelled locations were calculated and compared. The reallocation of ambulances to optimal locations improved response times and could contribute to higher survival rates from life-threatening medical events. Modelling EMS case 'demand' over census areas allows the data to be correlated to population characteristics and optimal 'supply' locations to be identified. Comparing current and future optimal scenarios allows more nuanced planning decisions to be made. This is a generic methodology that could be used to provide evidence in support of public health planning and decision making.
Simulation and optimization model for irrigation planning and management
NASA Astrophysics Data System (ADS)
Kuo, Sheng-Feng; Liu, Chen-Wuing
2003-10-01
A simulation and optimization model was developed and applied to an irrigated area in Delta, Utah to optimize the economic benefit, simulate the water demand, and search the related crop area percentages with specified water supply and planted area constraints. The user interface model begins with the weather generation submodel, which produces daily weather data, which is based on long-term monthly average and standard deviation data from Delta, Utah. To simulate the daily crop water demand and relative crop yield for seven crops in two command areas, the information provided by this submodel was applied to the on-farm irrigation scheduling submodel. Furthermore, to optimize the project benefit by searching for the best allocation of planted crop areas given the constraints of projected water supply, the results were employed in the genetic algorithm submodel. Optimal planning for the 394·6-ha area of the Delta irrigation project is projected to produce the maximum economic benefit. That is, projected profit equals US$113 826 and projected water demand equals 3·03 × 106 m3. Also, area percentages of crops within UCA#2 command area are 70·1%, 19% and 10·9% for alfalfa, barley and corn, respectively, and within UCA#4 command area are 41·5%, 38·9%, 14·4% and 5·2% for alfalfa, barley, corn and wheat, respectively. As this model can plan irrigation application depths and allocate crop areas for optimal economic benefit, it can thus be applied to many irrigation projects. Copyright
Registration of 3D ultrasound computer tomography and MRI for evaluation of tissue correspondences
NASA Astrophysics Data System (ADS)
Hopp, T.; Dapp, R.; Zapf, M.; Kretzek, E.; Gemmeke, H.; Ruiter, N. V.
2015-03-01
3D Ultrasound Computer Tomography (USCT) is a new imaging method for breast cancer diagnosis. In the current state of development it is essential to correlate USCT with a known imaging modality like MRI to evaluate how different tissue types are depicted. Due to different imaging conditions, e.g. with the breast subject to buoyancy in USCT, a direct correlation is demanding. We present a 3D image registration method to reduce positioning differences and allow direct side-by-side comparison of USCT and MRI volumes. It is based on a two-step approach including a buoyancy simulation with a biomechanical model and free form deformations using cubic B-Splines for a surface refinement. Simulation parameters are optimized patient-specifically in a simulated annealing scheme. The method was evaluated with in-vivo datasets resulting in an average registration error below 5mm. Correlating tissue structures can thereby be located in the same or nearby slices in both modalities and three-dimensional non-linear deformations due to the buoyancy are reduced. Image fusion of MRI volumes and USCT sound speed volumes was performed for intuitive display. By applying the registration to data of our first in-vivo study with the KIT 3D USCT, we could correlate several tissue structures in MRI and USCT images and learn how connective tissue, carcinomas and breast implants observed in the MRI are depicted in the USCT imaging modes.
Capacity withholding in wholesale electricity markets: The experience in England and Wales
NASA Astrophysics Data System (ADS)
Quinn, James Arnold
This thesis examines the incentives wholesale electricity generators face to withhold generating capacity from centralized electricity spot markets. The first chapter includes a brief history of electricity industry regulation in England and Wales and in the United States, including a description of key institutional features of England and Wales' restructured electricity market. The first chapter also includes a review of the literature on both bid price manipulation and capacity bid manipulation in centralized electricity markets. The second chapter details a theoretical model of wholesale generator behavior in a single price electricity market. A duopoly model is specified under the assumption that demand is non-stochastic. This model assumes that duopoly generators offer to sell electricity at their marginal cost, but can withhold a continuous segment of their capacity from the market. The Nash equilibrium withholding strategy of this model involves each duopoly generator withholding so that it produces the Cournot equilibrium output. A monopoly model along the lines of the duopoly model is specified and simulated under the assumption that demand is stochastic. The optimal strategy depends on the degree of demand uncertainty. When there is a moderate degree of demand uncertainty, the optimal withholding strategy involves production inefficiencies. When there is a high degree of demand uncertainty, the optimal monopoly quantity is greater than the optimal output level when demand is non-stochastic. The third chapter contains an empirical examination of the behavior of generators in the wholesale electricity market in England and Wales in the early 1990's. The wholesale market in England and Wales is analyzed because the industry structure in the early 1990's created a natural experiment, which is described in this chapter, whereby one of the two dominant generators had no incentive to behave non-competitively. This chapter develops a classification methodology consistent with the equilibrium identified in the second chapter. The availability of generating units owned by the two dominant generators is analyzed based on this classification system. This analysis includes the use of sample statistics as well as estimates from a dynamic random effects probit model. The analysis suggests a minimal degree of capacity withholding.
NASA Astrophysics Data System (ADS)
Zheng, Yingying
The growing energy demands and needs for reducing carbon emissions call more and more attention to the development of renewable energy technologies and management strategies. Microgrids have been developed around the world as a means to address the high penetration level of renewable generation and reduce greenhouse gas emissions while attempting to address supply-demand balancing at a more local level. This dissertation presents a model developed to optimize the design of a biomass-integrated renewable energy microgrid employing combined heat and power with energy storage. A receding horizon optimization with Monte Carlo simulation were used to evaluate optimal microgrid design and dispatch under uncertainties in the renewable energy and utility grid energy supplies, the energy demands, and the economic assumptions so as to generate a probability density function for the cost of energy. Case studies were examined for a conceptual utility grid-connected microgrid application in Davis, California. The results provide the most cost effective design based on the assumed energy load profile, local climate data, utility tariff structure, and technical and financial performance of the various components of the microgrid. Sensitivity and uncertainty analyses are carried out to illuminate the key parameters that influence the energy costs. The model application provides a means to determine major risk factors associated with alternative design integration and operating strategies.
Optimal Coordination of Building Loads and Energy Storage for Power Grid and End User Services
Hao, He; Wu, Di; Lian, Jianming; ...
2017-01-18
Demand response and energy storage play a profound role in the smart grid. The focus of this study is to evaluate benefits of coordinating flexible loads and energy storage to provide power grid and end user services. We present a Generalized Battery Model (GBM) to describe the flexibility of building loads and energy storage. An optimization-based approach is proposed to characterize the parameters (power and energy limits) of the GBM for flexible building loads. We then develop optimal coordination algorithms to provide power grid and end user services such as energy arbitrage, frequency regulation, spinning reserve, as well as energymore » cost and demand charge reduction. Several case studies have been performed to demonstrate the efficacy of the GBM and coordination algorithms, and evaluate the benefits of using their flexibility for power grid and end user services. We show that optimal coordination yields significant cost savings and revenue. Moreover, the best option for power grid services is to provide energy arbitrage and frequency regulation. Finally and furthermore, when coordinating flexible loads with energy storage to provide end user services, it is recommended to consider demand charge in addition to time-of-use price in order to flatten the aggregate power profile.« less
Modelling and Optimising the Value of a Hybrid Solar-Wind System
NASA Astrophysics Data System (ADS)
Nair, Arjun; Murali, Kartik; Anbuudayasankar, S. P.; Arjunan, C. V.
2017-05-01
In this paper, a net present value (NPV) approach for a solar hybrid system has been presented. The system, in question aims at supporting an investor by assessing an investment in solar-wind hybrid system in a given area. The approach follow a combined process of modelling the system, with optimization of major investment-related variables to maximize the financial yield of the investment. The consideration of solar wind hybrid supply presents significant potential for cost reduction. The investment variables concern the location of solar wind plant, and its sizing. The system demand driven, meaning that its primary aim is to fully satisfy the energy demand of the customers. Therefore, the model is a practical tool in the hands of investor to assess and optimize in financial terms an investment aiming at covering real energy demand. Optimization is performed by taking various technical, logical constraints. The relation between the maximum power obtained between individual system and the hybrid system as a whole in par with the net present value of the system has been highlighted.
Quantifying side-chain conformational variations in protein structure
Miao, Zhichao; Cao, Yang
2016-01-01
Protein side-chain conformation is closely related to their biological functions. The side-chain prediction is a key step in protein design, protein docking and structure optimization. However, side-chain polymorphism comprehensively exists in protein as various types and has been long overlooked by side-chain prediction. But such conformational variations have not been quantitatively studied and the correlations between these variations and residue features are vague. Here, we performed statistical analyses on large scale data sets and found that the side-chain conformational flexibility is closely related to the exposure to solvent, degree of freedom and hydrophilicity. These analyses allowed us to quantify different types of side-chain variabilities in PDB. The results underscore that protein side-chain conformation prediction is not a single-answer problem, leading us to reconsider the assessment approaches of side-chain prediction programs. PMID:27845406
Quantifying side-chain conformational variations in protein structure
NASA Astrophysics Data System (ADS)
Miao, Zhichao; Cao, Yang
2016-11-01
Protein side-chain conformation is closely related to their biological functions. The side-chain prediction is a key step in protein design, protein docking and structure optimization. However, side-chain polymorphism comprehensively exists in protein as various types and has been long overlooked by side-chain prediction. But such conformational variations have not been quantitatively studied and the correlations between these variations and residue features are vague. Here, we performed statistical analyses on large scale data sets and found that the side-chain conformational flexibility is closely related to the exposure to solvent, degree of freedom and hydrophilicity. These analyses allowed us to quantify different types of side-chain variabilities in PDB. The results underscore that protein side-chain conformation prediction is not a single-answer problem, leading us to reconsider the assessment approaches of side-chain prediction programs.
Quantifying side-chain conformational variations in protein structure.
Miao, Zhichao; Cao, Yang
2016-11-15
Protein side-chain conformation is closely related to their biological functions. The side-chain prediction is a key step in protein design, protein docking and structure optimization. However, side-chain polymorphism comprehensively exists in protein as various types and has been long overlooked by side-chain prediction. But such conformational variations have not been quantitatively studied and the correlations between these variations and residue features are vague. Here, we performed statistical analyses on large scale data sets and found that the side-chain conformational flexibility is closely related to the exposure to solvent, degree of freedom and hydrophilicity. These analyses allowed us to quantify different types of side-chain variabilities in PDB. The results underscore that protein side-chain conformation prediction is not a single-answer problem, leading us to reconsider the assessment approaches of side-chain prediction programs.
Tailoring the Employment of Offshore Wind Turbine Support Structure Load Mitigation Controllers
NASA Astrophysics Data System (ADS)
Shrestha, Binita; Kühn, Martin
2016-09-01
The currently available control concepts to mitigate aerodynamic and hydrodynamic induced support structure loads reduce either fore-aft or side-to-side damage under certain operational conditions. The load reduction is achieved together with an increase in loads in other components of the turbine e.g. pitch actuators or drive train, increasing the risk of unscheduled maintenance. The main objective of this paper is to demonstrate a methodology for reduction of support structure damage equivalent loads (DEL) in fore-aft and side-to-side directions using already available control concepts. A multi-objective optimization problem is formulated to minimize the DELs, while limiting the collateral effects of the control algorithms for load reduction. The optimization gives trigger values of sea state condition for the activation or deactivation of certain control concepts. As a result, by accepting the consumption of a small fraction of the load reserve in the design load envelope of other turbine components, a considerable reduction of the support structure loads is facilitated.
ERIC Educational Resources Information Center
Gluckman, Ivan B.
1985-01-01
Civil libertarians and members of more conservative special interest groups have equally legitimate concerns for the educational needs of students attending public schools. The goals and desires of concerned citizens from both sides can be met if neither makes unreasonable demands upon each other. (MD)
Information Professionals in the Digital Age.
ERIC Educational Resources Information Center
Cronin, Blaise
1998-01-01
Describes the strategic significance of information and intelligence management to socioeconomic growth. Considers implications in terms of human and structural intellectual capital development. Provides demand- and supply-side analyses of the knowledge and skills required of information professionals in the digital age. (Author)
VandenBrooks, John M; Gstrein, Gregory; Harmon, Jason; Friedman, Jessica; Olsen, Matthew; Ward, Anna; Parker, Gregory
2018-04-01
Atmospheric oxygen is one of the most important atmospheric component for all terrestrial organisms. Variation in atmospheric oxygen has wide ranging effects on animal physiology, development, and evolution. This variation in oxygen has the potential to affect both respiratory systems (the supply side) and mitochondrial networks (the demand side) in animals. Insect respiratory systems supplying oxygen to tissues in the gas phase through blind ended tracheal systems are particularly susceptible to this variation. While the large conducting tracheae have previously been shown to respond developmentally to changes in rearing oxygen, the effect of oxygen on the tracheolar network has been relatively unexplored, especially in adult insects. Similarly, mitochondrial networks that meet energy demand in insects and other animals are dynamic and their enzyme activities have been shown to vary in the presence of oxygen. These two systems together should be under selective pressure to meet the aerobic metabolic requirements of insects. To test this hypothesis, we reared Mito-YFP Drosophila under three different oxygen concentrations hypoxia (12%), normoxia (21%), and hyperoxia (31%) and imaged their tracheolar and mitochondrial networks within their flight muscle using confocal microscopy. In terms of oxygen supply, hypoxia increased mean (mid-length) tracheolar diameters, tracheolar tip diameters, the number of tracheoles per main branch and affected tracheal branching patterns, while the opposite was observed in hyperoxia. In terms of oxygen demand, hypoxia increased mitochondrial investment and mitochondrial to tracheolar volume ratios; while the opposite was observed in hyperoxia. Generally, hypoxia had a stronger effect on both systems than hyperoxia. These results show that insects are capable of developmentally changing investment in both their supply and demand networks to increase overall fitness. Copyright © 2017 Elsevier Ltd. All rights reserved.
Liu, Peng; Fan, Liyun; Hayat, Qaisar; Xu, De; Ma, Xiuzhen; Song, Enzhe
2014-01-01
Analysis consisting of numerical simulations along with lab experiments of interaction effects between key parameters on the electromagnetic force based on response surface methodology (RSM) has been also proposed to optimize the design of high-speed solenoid valve (HSV) and improve its performance. Numerical simulation model of HSV has been developed in Ansoft Maxwell environment and its accuracy has been validated through lab experiments. Effect of change of core structure, coil structure, armature structure, working air gap, and drive current on the electromagnetic force of HSV has been analyzed through simulation model and influence rules of various parameters on the electromagnetic force have been established. The response surface model of the electromagnetic force has been utilized to analyze the interaction effect between major parameters. It has been concluded that six interaction factors including working air gap with armature radius, drive current with armature thickness, coil turns with side pole radius, armature thickness with its radius, armature thickness with side pole radius, and armature radius with side pole radius have significant influence on the electromagnetic force. Optimal match values between coil turns and side pole radius; armature thickness and side pole radius; and armature radius and side pole radius have also been determined.
Fan, Liyun; Xu, De; Ma, Xiuzhen; Song, Enzhe
2014-01-01
Analysis consisting of numerical simulations along with lab experiments of interaction effects between key parameters on the electromagnetic force based on response surface methodology (RSM) has been also proposed to optimize the design of high-speed solenoid valve (HSV) and improve its performance. Numerical simulation model of HSV has been developed in Ansoft Maxwell environment and its accuracy has been validated through lab experiments. Effect of change of core structure, coil structure, armature structure, working air gap, and drive current on the electromagnetic force of HSV has been analyzed through simulation model and influence rules of various parameters on the electromagnetic force have been established. The response surface model of the electromagnetic force has been utilized to analyze the interaction effect between major parameters. It has been concluded that six interaction factors including working air gap with armature radius, drive current with armature thickness, coil turns with side pole radius, armature thickness with its radius, armature thickness with side pole radius, and armature radius with side pole radius have significant influence on the electromagnetic force. Optimal match values between coil turns and side pole radius; armature thickness and side pole radius; and armature radius and side pole radius have also been determined. PMID:25243217
Optimal crop selection and water allocation under limited water supply in irrigation
NASA Astrophysics Data System (ADS)
Stange, Peter; Grießbach, Ulrike; Schütze, Niels
2015-04-01
Due to climate change, extreme weather conditions such as droughts may have an increasing impact on irrigated agriculture. To cope with limited water resources in irrigation systems, a new decision support framework is developed which focuses on an integrated management of both irrigation water supply and demand at the same time. For modeling the regional water demand, local (and site-specific) water demand functions are used which are derived from optimized agronomic response on farms scale. To account for climate variability the agronomic response is represented by stochastic crop water production functions (SCWPF). These functions take into account different soil types, crops and stochastically generated climate scenarios. The SCWPF's are used to compute the water demand considering different conditions, e.g., variable and fixed costs. This generic approach enables the consideration of both multiple crops at farm scale as well as of the aggregated response to water pricing at a regional scale for full and deficit irrigation systems. Within the SAPHIR (SAxonian Platform for High Performance IRrigation) project a prototype of a decision support system is developed which helps to evaluate combined water supply and demand management policies.
Addressing the minimum fleet problem in on-demand urban mobility.
Vazifeh, M M; Santi, P; Resta, G; Strogatz, S H; Ratti, C
2018-05-01
Information and communication technologies have opened the way to new solutions for urban mobility that provide better ways to match individuals with on-demand vehicles. However, a fundamental unsolved problem is how best to size and operate a fleet of vehicles, given a certain demand for personal mobility. Previous studies 1-5 either do not provide a scalable solution or require changes in human attitudes towards mobility. Here we provide a network-based solution to the following 'minimum fleet problem', given a collection of trips (specified by origin, destination and start time), of how to determine the minimum number of vehicles needed to serve all the trips without incurring any delay to the passengers. By introducing the notion of a 'vehicle-sharing network', we present an optimal computationally efficient solution to the problem, as well as a nearly optimal solution amenable to real-time implementation. We test both solutions on a dataset of 150 million taxi trips taken in the city of New York over one year 6 . The real-time implementation of the method with near-optimal service levels allows a 30 per cent reduction in fleet size compared to current taxi operation. Although constraints on driver availability and the existence of abnormal trip demands may lead to a relatively larger optimal value for the fleet size than that predicted here, the fleet size remains robust for a wide range of variations in historical trip demand. These predicted reductions in fleet size follow directly from a reorganization of taxi dispatching that could be implemented with a simple urban app; they do not assume ride sharing 7-9 , nor require changes to regulations, business models, or human attitudes towards mobility to become effective. Our results could become even more relevant in the years ahead as fleets of networked, self-driving cars become commonplace 10-14 .
The Portuguese generic medicines market: a policy analysis
Simoens, Steven
2008-01-01
Objectives: This study aims to conduct a descriptive analysis of the policy environment surrounding the generic medicines retail market in Portugal. The policy analysis focuses on supply-side measures (i.e. market access, pricing, reference-pricing and reimbursement of generic medicines) and demand-side measures (i.e. incentives for physicians to prescribe, for pharmacists to dispense and for patients to use generic medicines). Methods: The policy analysis was based on an international literature review. Also, a simulation exercise was carried out to compute potential savings from substituting generic for originator medicines in Portugal using IMS Health data. Results: Portugal has developed a successful generic medicines market by increasing reimbursement of generic medicines (until October 2005), by introducing a reference-pricing system, by encouraging physicians to prescribe by international non-proprietary name (INN), and by allowing generic substitution by pharmacists. However, the development of the generic medicines market has been hindered by the existence of copies, pricing regulation, certain features of the reference-pricing system, weak incentives for physicians to prescribe generic medicines and a financial disincentive for pharmacists to dispense generic medicines. Increased generic substitution would be expected to reduce public expenditure on originator medicines by 45%. Conclusions: The development of the Portuguese generic medicines market has mainly been fuelled by supply-side measures. To support the further expansion of the market, policy makers need to strengthen demand-side measures inciting physicians to prescribe, pharmacists to dispense and patients to use generic medicines. PMID:25152781
Miao, Zhidong; Liu, Dake; Gong, Chen
2017-10-01
Inductive wireless power transfer (IWPT) is a promising power technology for implantable biomedical devices, where the power consumption is low and the efficiency is the most important consideration. In this paper, we propose an optimization method of impedance matching networks (IMN) to maximize the IWPT efficiency. The IMN at the load side is designed to achieve the optimal load, and the IMN at the source side is designed to deliver the required amount of power (no-more-no-less) from the power source to the load. The theoretical analyses and design procedure are given. An IWPT system for an implantable glaucoma therapeutic prototype is designed as an example. Compared with the efficiency of the resonant IWPT system, the efficiency of our optimized system increases with a factor of 1.73. Besides, the efficiency of our optimized IWPT system is 1.97 times higher than that of the IWPT system optimized by the traditional maximum power transfer method. All the discussions indicate that the optimization method proposed in this paper could achieve a high efficiency and long working time when the system is powered by a battery.
NASA Astrophysics Data System (ADS)
Matrosov, E.; Padula, S.; Huskova, I.; Harou, J. J.
2012-12-01
Population growth and the threat of drier or changed climates are likely to increase water scarcity world-wide. A combination of demand management (water conservation) and new supply infrastructure is often needed to meet future projected demands. In this case system planners must decide what to implement, when and at what capacity. Choices can range from infrastructure to policies or a mix of the two, culminating in a complex planning problem. Decision making under uncertainty frameworks can be used to help planners with this planning problem. This presentation introduces, applies and compares four decision making under uncertainty frameworks. The application is to the Thames basin water resource system which includes the city of London. The approaches covered here include least-economic cost capacity expansion optimization (EO), Robust Decision Making (RDM), Info-Gap Decision Theory (Info-gap) and many-objective evolutionary optimization (MOEO). EO searches for the least-economic cost program, i.e. the timing, sizing, and choice of supply-demand management actions/upgrades which meet projected water demands. Instead of striving for optimality, the RDM and Info-gap approaches help build plans that are robust to 'deep' uncertainty in future conditions. The MOEO framework considers multiple performance criteria and uses water systems simulators as a function evaluator for the evolutionary algorithm. Visualizations show Pareto approximate tradeoffs between multiple objectives. In this presentation we detail the application of each framework to the Thames basin (including London) water resource planning problem. Supply and demand options are proposed by the major water companies in the basin. We apply the EO method using a 29 year time horizon and an annual time step considering capital, operating (fixed and variable), social and environmental costs. The method considers all plausible combinations of supply and conservation schemes and capacities proposed by water companies and generates the least-economic cost annual plan. The RDM application uses stochastic simulation under a weekly time-step and regret analysis to choose a candidate strategy. We then use a statistical cluster algorithm to identify future states of the world under which the strategy is vulnerable. The method explicitly considers the effects of uncertainty in supply, demands and energy price on multiple performance criteria. The Info-gap approach produces robustness and opportuneness plots that show the performance of different plans under the most dire and favorable sets of future conditions. The same simulator, supply and demand options and uncertainties are considered as in the RDM application. The MOEO application considers many more combinations of supply and demand options while still employing a simulator that enables a more realistic representation of the physical system and operating rules. A computer cluster is employed to ease the computational burden. Visualization software allows decision makers to interactively view tradeoffs in many dimensions. Benefits and limitations of each framework are discussed and recommendations for future planning in the basin are provided.
EOQ model for perishable products with price-dependent demand, pre and post discounted selling price
NASA Astrophysics Data System (ADS)
Santhi, G.; Karthikeyan, K.
2017-11-01
In this article we introduce an economic order quantity model for perishable products like vegetables, fruits, milk, flowers, meat, etc.,with price-dependent demand, pre and post discounted selling price. Here we consider the demand is depending on selling price and deterioration rate is constant. Here we developed mathematical model to determine optimal discounton the unit selling price to maximize total profit. Numerical examples are given for illustrated.
Systems and methods for energy cost optimization in a building system
Turney, Robert D.; Wenzel, Michael J.
2016-09-06
Methods and systems to minimize energy cost in response to time-varying energy prices are presented for a variety of different pricing scenarios. A cascaded model predictive control system is disclosed comprising an inner controller and an outer controller. The inner controller controls power use using a derivative of a temperature setpoint and the outer controller controls temperature via a power setpoint or power deferral. An optimization procedure is used to minimize a cost function within a time horizon subject to temperature constraints, equality constraints, and demand charge constraints. Equality constraints are formulated using system model information and system state information whereas demand charge constraints are formulated using system state information and pricing information. A masking procedure is used to invalidate demand charge constraints for inactive pricing periods including peak, partial-peak, off-peak, critical-peak, and real-time.
NASA Astrophysics Data System (ADS)
Soni, Hardik N.; Chauhan, Ashaba D.
2018-03-01
This study models a joint pricing, inventory, and preservation decision-making problem for deteriorating items subject to stochastic demand and promotional effort. The generalized price-dependent stochastic demand, time proportional deterioration, and partial backlogging rates are used to model the inventory system. The objective is to find the optimal pricing, replenishment, and preservation technology investment strategies while maximizing the total profit per unit time. Based on the partial backlogging and lost sale cases, we first deduce the criterion for optimal replenishment schedules for any given price and technology investment cost. Second, we show that, respectively, total profit per time unit is concave function of price and preservation technology cost. At the end, some numerical examples and the results of a sensitivity analysis are used to illustrate the features of the proposed model.
Microgrid to enable optimal distributed energy retail and end-user demand response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jin, Ming; Feng, Wei; Marnay, Chris
In the face of unprecedented challenges in environmental sustainability and grid resilience, there is an increasingly held consensus regarding the adoption of distributed and renewable energy resources such as microgrids (MGs), and the utilization of flexible electric loads by demand response (DR) to potentially drive a necessary paradigm shift in energy production and consumption patterns. However, the potential value of distributed generation and demand flexibility has not yet been fully realized in the operation of MGs. This study investigates the pricing and operation strategy with DR for a MG retailer in an integrated energy system (IES). Based on co-optimizing retailmore » rates and MG dispatch formulated as a mixed integer quadratic programming (MIQP) problem, our model devises a dynamic pricing scheme that reflects the cost of generation and promotes DR, in tandem with an optimal dispatch plan that exploits spark spread and facilitates the integration of renewables, resulting in improved retailer profits and system stability. Main issues like integrated energy coupling and customer bill reduction are addressed during pricing to ensure rates competitiveness and customer protection. By evaluating on real datasets, the system is demonstrated to optimally coordinate storage, renewables, and combined heat and power (CHP), reduce carbon dioxide emission while maintaining profits, and effectively alleviate the PV curtailment problem. Finally, the model can be used by retailers and MG operators to optimize their operations, as well as regulators to design new utility rates in support of the ongoing transformation of energy systems.« less
Microgrid to enable optimal distributed energy retail and end-user demand response
Jin, Ming; Feng, Wei; Marnay, Chris; ...
2018-06-07
In the face of unprecedented challenges in environmental sustainability and grid resilience, there is an increasingly held consensus regarding the adoption of distributed and renewable energy resources such as microgrids (MGs), and the utilization of flexible electric loads by demand response (DR) to potentially drive a necessary paradigm shift in energy production and consumption patterns. However, the potential value of distributed generation and demand flexibility has not yet been fully realized in the operation of MGs. This study investigates the pricing and operation strategy with DR for a MG retailer in an integrated energy system (IES). Based on co-optimizing retailmore » rates and MG dispatch formulated as a mixed integer quadratic programming (MIQP) problem, our model devises a dynamic pricing scheme that reflects the cost of generation and promotes DR, in tandem with an optimal dispatch plan that exploits spark spread and facilitates the integration of renewables, resulting in improved retailer profits and system stability. Main issues like integrated energy coupling and customer bill reduction are addressed during pricing to ensure rates competitiveness and customer protection. By evaluating on real datasets, the system is demonstrated to optimally coordinate storage, renewables, and combined heat and power (CHP), reduce carbon dioxide emission while maintaining profits, and effectively alleviate the PV curtailment problem. Finally, the model can be used by retailers and MG operators to optimize their operations, as well as regulators to design new utility rates in support of the ongoing transformation of energy systems.« less
Economic environmental dispatch using BSA algorithm
NASA Astrophysics Data System (ADS)
Jihane, Kartite; Mohamed, Cherkaoui
2018-05-01
Economic environmental dispatch problem (EED) is an important issue especially in the field of fossil fuel power plant system. It allows the network manager to choose among different units the most optimized in terms of fuel costs and emission level. The objective of this paper is to minimize the fuel cost with emissions constrained; the test is conducted for two cases: six generator unit and ten generator unit for the same power demand 1200Mw. The simulation has been computed in MATLAB and the result shows the robustness of the Backtracking Search optimization Algorithm (BSA) and the impact of the load demand on the emission.
Synthesis and analgesic activity of some side-chain modified anpirtoline derivatives.
Rádl, S; Hezky, P; Proska, J; Hejnová, L; Krejcí, I
2000-05-01
New derivatives of anpirtoline and deazaanpirtoline modified in the side chain have been synthesized. The series includes compounds 3 with side-chains containing piperidine or pyrrolidine rings, compounds 4 containing 8-azabicyclo[3.2.1]octane moiety, and compounds 5 having piperazine ring in their side-chains. Their receptor binding profiles (5-HT1A, 5-HT1B) and analgesic activity (hot plate, acetic acid induced writhing) have been studied. Optimized structures (PM3-MOPAC, Alchemy 2000, Tripos Inc.) of the synthesized compounds 3-5 were compared with that of anpirtoline.
Optimized Ce:LiCAF amplifier pumping configurations
NASA Astrophysics Data System (ADS)
Cadatal-Raduban, Marilou; Pham, Minh Hong; Gabayno, Jacque Lynn; Yamanoi, Kohei; Empizo, Melvin John F.; Shimizu, Toshihiko; Sarukura, Nobuhiko; Nguyen, Hung Dai; Yoshikawa, Akira; Fukuda, Tsuguo
2018-02-01
Two side-pumping schemes suitable for the development of an ultraviolet femtosecond amplifier system using a Ce3+:LiCaAlF6 crystal are reported. Firstly, a Bethune-type prismatic cell configuration that uniformly illuminates the four sides of a micro-pulling down method-grown crystal is used to amplify 290 nm, femtosecond pulses with no significant increase in pulse duration and B-integral. The second pumping scheme uses a two-side-pumped large crystal. These two side-pumping schemes can pave new possibilities for achieving high-energy ultraviolet femtosecond pulses.
NASA Astrophysics Data System (ADS)
Li, Zhi; Li, Chunhui; Wang, Xuan; Peng, Cong; Cai, Yanpeng; Huang, Weichen
2018-01-01
Problems with water resources restrict the sustainable development of a city with water shortages. Based on system dynamics (SD) theory, a model of sustainable utilization of water resources using the STELLA software has been established. This model consists of four subsystems: population system, economic system, water supply system and water demand system. The boundaries of the four subsystems are vague, but they are closely related and interdependent. The model is applied to Zhengzhou City, China, which has a serious water shortage. The difference between the water supply and demand is very prominent in Zhengzhou City. The model was verified with data from 2009 to 2013. The results show that water demand of Zhengzhou City will reach 2.57 billion m3 in 2020. A water resources optimization model is developed based on interval-parameter two-stage stochastic programming. The objective of the model is to allocate water resources to each water sector and make the lowest cost under the minimum water demand. Using the simulation results, decision makers can easily weigh the costs of the system, the water allocation objectives, and the system risk. The hybrid system dynamics method and optimization model is a rational try to support water resources management in many cities, particularly for cities with potential water shortage and it is solidly supported with previous studies and collected data.
Impact of adherence on the outcome of antiviral therapy for chronic hepatitis C.
Mulhall, Brian P; Younossi, Zobair
2005-01-01
Nearly 4 million people in the United States have evidence of hepatitis C infection (HCV), representing a significant cause of cirrhosis and liver cancer as well a major burden to our healthcare systems and society. Antiviral therapy can successfully eradicate HCV over the long term, potentially reducing the risk of progression and improving patients' quality of life. The currently preferred HCV treatment is a combination of pegylated interferon alfa and ribavirin, which can achieve an overall sustained viral eradication rate of 55%. The duration of this treatment is typically determined by HCV genotype and the patient's early virologic response to the antiviral regimen. Evidence has accumulated over the past few years to indicate that close adherence to the optimal antiviral regimen can enhance sustained virologic response. But optimal treatment outcomes require diligence and careful management of side effects related to combination therapy. Although reducing the dose of pegylated interferon alfa, ribavirin, or both can effectively treat side effects, suboptimal doses of this regimen, especially ribavirin, may negatively affect virologic response. An alternative strategy is to use growth factors to treat cytopenias. This strategy can obviate dose reductions while potentially improving patients' quality of life. Patient support seems especially important early after the initiation of antiviral therapy. Encouraging study findings involving the growth factors, epoetin alfa and darbepoetin alfa, suggest improved anemia and quality of life while maintaining the optimal ribavirin dose. Future work should be aimed at providing stronger evidence for the use of these "supportive products" during anti-HCV therapy. As we strive to develop better treatment options for our HCV patients, the importance of adhering to the treatment regimen continues to play a central role. Effective side effect management is crucial for the success of this treatment because adherence is negatively affected by side effects related to the antiviral regimen. By identifying and addressing the important side effects of combination therapy for HCV, adherence to treatment can be improved and optimal outcomes can be achieved.
Design of stapled DNA-minor-groove-binding molecules with a mutable atom simulated annealing method
NASA Astrophysics Data System (ADS)
Walker, Wynn L.; Kopka, Mary L.; Dickerson, Richard E.; Goodsell, David S.
1997-11-01
We report the design of optimal linker geometries for the synthesis of stapledDNA-minor-groove-binding molecules. Netropsin, distamycin, and lexitropsinsbind side-by-side to mixed-sequence DNA and offer an opportunity for thedesign of sequence-reading molecules. Stapled molecules, with two moleculescovalently linked side-by-side, provide entropic gains and restrain theposition of one molecule relative to its neighbor. Using a free-atom simulatedannealing technique combined with a discrete mutable atom definition, optimallengths and atomic composition for covalent linkages are determined, and anovel hydrogen bond `zipper' is proposed to phase two molecules accuratelyside-by-side.
NASA Astrophysics Data System (ADS)
Hamdani, Irfan Hilmi; Jauhari, Wakhid Ahmad; Rosyidi, Cucuk Nur
2017-11-01
This paper develops an integrated inventory model consisting of single-vendor and single-buyer system. The demand in buyer side is deterministic and the production process is imperfect and produces a certain number of defective items. The delivery within a single production batch from vendor to buyer is increasing by a fixed factor. After the delivery arrives at the buyer, an inspection process is conducted. The inspection process in not perfect. Errors may occur when the inspector is misclassifies a non-defective item as defective ne, or incorrectly classifies a defective item as non-defective. All the product which defective will be repair by repair-shop. After the defective arrives at repair shop, will perfect inspection. The defective item will repair and back to buyer. This model provides an optimal solution for the expected integrated total annual cost of the vendor and the buyer. The result from numerical examples shows that the integrated model will result in lower joint total cost in comparison with the equal-sized policy.
Nanowire decorated, ultra-thin, single crystalline silicon for photovoltaic devices.
Aurang, Pantea; Turan, Rasit; Unalan, Husnu Emrah
2017-10-06
Reducing silicon (Si) wafer thickness in the photovoltaic industry has always been demanded for lowering the overall cost. Further benefits such as short collection lengths and improved open circuit voltages can also be achieved by Si thickness reduction. However, the problem with thin films is poor light absorption. One way to decrease optical losses in photovoltaic devices is to minimize the front side reflection. This approach can be applied to front contacted ultra-thin crystalline Si solar cells to increase the light absorption. In this work, homojunction solar cells were fabricated using ultra-thin and flexible single crystal Si wafers. A metal assisted chemical etching method was used for the nanowire (NW) texturization of ultra-thin Si wafers to compensate weak light absorption. A relative improvement of 56% in the reflectivity was observed for ultra-thin Si wafers with the thickness of 20 ± 0.2 μm upon NW texturization. NW length and top contact optimization resulted in a relative enhancement of 23% ± 5% in photovoltaic conversion efficiency.
NASA Astrophysics Data System (ADS)
Bleile, A.; Egelhof, P.; Kraft, S.; McCammon, D.; Meier, H. J.; Shrivastava, A.; Stahle, C. K.; Weber, M.
2002-02-01
The accurate determination of the Lamb shift in heavy hydrogen-like ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields, not accessible otherwise. For the investigation of the Lyman-α transitions in 208Pb81+ or 238U91+ with sufficient accuracy, a high resolution calorimetric detector for hard x-rays (E<=100 keV) is presently being developed. The detector modules consist of arrays of silicon thermistors and of x-ray absorbers made of high-Z material to optimize the absorption efficiency. The detectors are housed in a specially designed 3He/4He dilution refrigerator with a side arm which fits to the internal target geometry of the storage ring ESR at GSI Darmstadt. The detector performance presently achieved is already close to fulfill the demands of the Lamb shift experiment. For a prototype detector pixel with a 0.2 mm2×47 μm Pb absorber an energy resolution of ΔEFWHM=65 eV is obtained for 60 keV x-rays. .
Low-temperature X-ray detectors for precise Lamb shift measurements on hydrogen-like heavy ions
NASA Astrophysics Data System (ADS)
Bleile, A.; Egelhof, P.; Kluge, H.-J.; Liebisch, U.; McCammon, D.; Meier, H. J.; Sebastián, O.; Stahle, C. K.; Weber, M.
2000-04-01
The precise determination of the Lamb shift in heavy hydrogen-like ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields, not accessible otherwise. For the investigation of the Lyman- α transitions in 208Pb81+ or 238U91+ with sufficient accuracy a high resolving calorimetric detector for hard X-rays ( E⩽100 keV) is presently developed. The detector modules consist of arrays of silicon thermistors and of X-ray absorbers made of high Z material to optimize the absorption efficiency. The detectors are housed in a specially designed 3He/ 4He dilution refrigerator with a side arm which fits to the geometry of the internal target of the storage ring ESR at GSI Darmstadt. The detector performance presently achieved is already close to fulfill the demands of the Lamb shift experiment. For a prototype detector pixel with a 0.3 mm 2×66 μm Sn absorber an energy resolution of Δ EFWHM=75 eV is obtained for 60 keV X-rays.
Polycrystalline CdTe detectors: A luminosity monitor for the LHC
NASA Astrophysics Data System (ADS)
Gschwendtner, E.; Placidia, M.; Schmicklera, H.
2003-09-01
The luminosity at the four interaction points of the Large Hadron Collider must be continuously monitored in order to provide an adequate tool for the control and optimization of the collision parameters and the beam optics. At both sides of the interaction points absorbers are installed to protect the super-conducting accelerator elements from quenches caused by the deposited energy of collision products. The luminosity detectors will be installed in the copper core of these absorbers to measure the electromagnetic and hadronic showers caused by neutral particles that are produced at the proton-proton collision in the interaction points. The detectors have to withstand extreme radiation levels (108 Gy/yr at the design luminosity) and their long-term operation has to be assured without requiring human intervention. In addition the demand for bunch-by-bunch luminosity measurements, i.e. 40 MHz detection speed, puts severe constraints on the detectors. Polycrystalline CdTe detectors have a high potential to fulfill the requirements and are considered as LHC luminosity monitors. In this paper the interaction region is shown and the characteristics of the CdTe detectors are presented.
Smart Buildings and Demand Response
NASA Astrophysics Data System (ADS)
Kiliccote, Sila; Piette, Mary Ann; Ghatikar, Girish
2011-11-01
Advances in communications and control technology, the strengthening of the Internet, and the growing appreciation of the urgency to reduce demand side energy use are motivating the development of improvements in both energy efficiency and demand response (DR) systems in buildings. This paper provides a framework linking continuous energy management and continuous communications for automated demand response (Auto-DR) in various times scales. We provide a set of concepts for monitoring and controls linked to standards and procedures such as Open Automation Demand Response Communication Standards (OpenADR). Basic building energy science and control issues in this approach begin with key building components, systems, end-uses and whole building energy performance metrics. The paper presents a framework about when energy is used, levels of services by energy using systems, granularity of control, and speed of telemetry. DR, when defined as a discrete event, requires a different set of building service levels than daily operations. We provide examples of lessons from DR case studies and links to energy efficiency.
Comprehensive Outcome Researches of Intralesional Steroid Injection on Benign Vocal Fold Lesions.
Wang, Chi-Te; Lai, Mei-Shu; Hsiao, Tzu-Yu
2015-09-01
This study investigated multidimensional treatment outcomes, including prognostic factors and side effects of vocal fold steroid injection (VFSI). We recruited 126 consecutive patients, including patients with 49 nodules, 47 polyps, and 30 mucus retention cysts. All the patients received VFSI under local anesthesia in the office settings. Treatment outcomes were evaluated 1 and 2 months after the procedure, including endoscopic evaluation, perceptual voice quality (GRB scores), acoustic analysis, and 10-item Voice Handicap Index (VHI-10). More than 80% of the patients reported subjective improvements after VFSI. Objective measurements revealed significant improvements from baseline in most of the outcome parameters (P<0.05). Higher occupational vocal demands and fibrotic vocal nodules were significantly associated with poorer clinical responses as measured by the VHI-10 and GRB scores, respectively. For vocal polyps, dysphonia for more than 12 months were significantly associated with higher postoperative VHI-10 scores, whereas patients with laryngopharyngeal reflux (LPR) showed significantly poor postoperative voice quality as measured by GRB scores. Side effects after VFSI included hematoma (27%), triamcinolone deposits (4%), and vocal atrophy (1%), which resolved spontaneously within 1-2 months. Presentation with vocal fold ectasias/varicosities and higher vocal demands were significantly correlated with postoperative vocal hematoma. This study demonstrated significant improvements after VFSI in vocal nodules, polyps, and cysts. Occupational vocal demand and subtypes of vocal nodules are closely related to the treatment outcomes after VFSI, whereas symptom duration and LPR were significant prognostic factors for VFSI treatment outcomes in vocal polyps. Side effects after receiving VFSI were mostly self-limited without sequel, whereas the incidence rates might be varied by the injection approach and the timing for postoperative follow-up. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
Moon, James C; Godman, Brian; Petzold, Max; Alvarez-Madrazo, Samantha; Bennett, Kathleen; Bishop, Iain; Bucsics, Anna; Hesse, Ulrik; Martin, Andrew; Simoens, Steven; Zara, Corinne; Malmström, Rickard E
2014-01-01
There is an urgent need for health authorities across Europe to fully realize potential savings from increased use of generics to sustain their healthcare systems. A variety of strategies were used across Europe following the availability of generic losartan, the first angiotensin receptor blocker (ARB) to be approved and marketed, to enhance its prescribing vs. single-sourced drugs in the class. Demand-side strategies ranged from 100% co-payment for single-sourced ARBs in Denmark to no specific measures. We hypothesized this heterogeneity of approaches would provide opportunities to explore prescribing in a class following patent expiry. Contrast the impact of the different approaches among European countries and regions to the availability of generic losartan to provide future guidance. Retrospective segmented regression analyses applying linear random coefficient models with country specific intercepts and slopes were used to assess the impact of the various initiatives across Europe following the availability of generic losartan. Utilization measured in defined daily doses (DDDs). Price reductions for generic losartan were also measured. Utilization of losartan was over 90% of all ARBs in Denmark by the study end. Multiple measures in Sweden and one English primary care group also appreciably enhanced losartan utilization. Losartan utilization actually fell in some countries with no specific demand-side measures. Considerable differences were seen in the prices of generic losartan. Delisting single-sourced ARBs produced the greatest increase in losartan utilization. Overall, multiple demand-side measures are needed to change physician prescribing habits to fully realize savings from generics. There is no apparent "spill over" effect from one class to another to influence future prescribing patterns even if these are closely related.
Risk-based water resources planning: Incorporating probabilistic nonstationary climate uncertainties
NASA Astrophysics Data System (ADS)
Borgomeo, Edoardo; Hall, Jim W.; Fung, Fai; Watts, Glenn; Colquhoun, Keith; Lambert, Chris
2014-08-01
We present a risk-based approach for incorporating nonstationary probabilistic climate projections into long-term water resources planning. The proposed methodology uses nonstationary synthetic time series of future climates obtained via a stochastic weather generator based on the UK Climate Projections (UKCP09) to construct a probability distribution of the frequency of water shortages in the future. The UKCP09 projections extend well beyond the range of current hydrological variability, providing the basis for testing the robustness of water resources management plans to future climate-related uncertainties. The nonstationary nature of the projections combined with the stochastic simulation approach allows for extensive sampling of climatic variability conditioned on climate model outputs. The probability of exceeding planned frequencies of water shortages of varying severity (defined as Levels of Service for the water supply utility company) is used as a risk metric for water resources planning. Different sources of uncertainty, including demand-side uncertainties, are considered simultaneously and their impact on the risk metric is evaluated. Supply-side and demand-side management strategies can be compared based on how cost-effective they are at reducing risks to acceptable levels. A case study based on a water supply system in London (UK) is presented to illustrate the methodology. Results indicate an increase in the probability of exceeding the planned Levels of Service across the planning horizon. Under a 1% per annum population growth scenario, the probability of exceeding the planned Levels of Service is as high as 0.5 by 2040. The case study also illustrates how a combination of supply and demand management options may be required to reduce the risk of water shortages.
Moon, James C.; Godman, Brian; Petzold, Max; Alvarez-Madrazo, Samantha; Bennett, Kathleen; Bishop, Iain; Bucsics, Anna; Hesse, Ulrik; Martin, Andrew; Simoens, Steven; Zara, Corinne; Malmström, Rickard E.
2014-01-01
Introduction: There is an urgent need for health authorities across Europe to fully realize potential savings from increased use of generics to sustain their healthcare systems. A variety of strategies were used across Europe following the availability of generic losartan, the first angiotensin receptor blocker (ARB) to be approved and marketed, to enhance its prescribing vs. single-sourced drugs in the class. Demand-side strategies ranged from 100% co-payment for single-sourced ARBs in Denmark to no specific measures. We hypothesized this heterogeneity of approaches would provide opportunities to explore prescribing in a class following patent expiry. Objective: Contrast the impact of the different approaches among European countries and regions to the availability of generic losartan to provide future guidance. Methodology: Retrospective segmented regression analyses applying linear random coefficient models with country specific intercepts and slopes were used to assess the impact of the various initiatives across Europe following the availability of generic losartan. Utilization measured in defined daily doses (DDDs). Price reductions for generic losartan were also measured. Results: Utilization of losartan was over 90% of all ARBs in Denmark by the study end. Multiple measures in Sweden and one English primary care group also appreciably enhanced losartan utilization. Losartan utilization actually fell in some countries with no specific demand-side measures. Considerable differences were seen in the prices of generic losartan. Conclusion: Delisting single-sourced ARBs produced the greatest increase in losartan utilization. Overall, multiple demand-side measures are needed to change physician prescribing habits to fully realize savings from generics. There is no apparent “spill over” effect from one class to another to influence future prescribing patterns even if these are closely related. PMID:25339902
Access barriers to obstetric care at health facilities in sub-Saharan Africa-a systematic review.
Kyei-Nimakoh, Minerva; Carolan-Olah, Mary; McCann, Terence V
2017-06-06
Since 2000, the United Nations' Millennium Development Goals, which included a goal to improve maternal health by the end of 2015, has facilitated significant reductions in maternal morbidity and mortality worldwide. However, despite more focused efforts made especially by low- and middle-income countries, targets were largely unmet in sub-Saharan Africa, where women are plagued by many challenges in seeking obstetric care. The aim of this review was to synthesise literature on barriers to obstetric care at health institutions in sub-Saharan Africa. This review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Scopus databases were electronically searched to identify studies on barriers to health facility-based obstetric care in sub-Saharan Africa, in English, and dated between 2000 and 2015. Combinations of search terms 'obstetric care', 'access', 'barriers', 'developing countries' and 'sub-Saharan Africa' were used to locate articles. Quantitative, qualitative and mixed-methods studies were considered. A narrative synthesis approach was employed to synthesise the evidence and explore relationships between included studies. One hundred and sixty articles met the inclusion criteria. Currently, obstetric care access is hindered by several demand- and supply-side barriers. The principal demand-side barriers identified were limited household resources/income, non-availability of means of transportation, indirect transport costs, a lack of information on health care services/providers, issues related to stigma and women's self-esteem/assertiveness, a lack of birth preparation, cultural beliefs/practices and ignorance about required obstetric health services. On the supply-side, the most significant barriers were cost of services, physical distance between health facilities and service users' residence, long waiting times at health facilities, poor staff knowledge and skills, poor referral practices and poor staff interpersonal relationships. Despite similarities in obstetric care barriers across sub-Saharan Africa, country-specific strategies are required to tackle the challenges mentioned. Governments need to develop strategies to improve healthcare systems and overall socioeconomic status of women, in order to tackle supply- and demand-side access barriers to obstetric care. It is also important that strategies adopted are supported by research evidence appropriate for local conditions. Finally, more research is needed, particularly, with regard to supply-side interventions that may improve the obstetric care experience of pregnant women. PROSPERO 2014 CRD42014015549.
Regional variation in health care utilization in Sweden - the importance of demand-side factors.
Johansson, Naimi; Jakobsson, Niklas; Svensson, Mikael
2018-06-04
Differences in health care utilization across geographical areas are well documented within several countries. If the variation across areas cannot be explained by differences in medical need, it can be a sign of inefficiency or misallocation of public health care resources. In this observational, longitudinal panel study we use regional level data covering the 21 Swedish regions (county councils) over 13 years and a random effects model to assess to what degree regional variation in outpatient physician visits is explained by observed demand factors such as health, demography and socio-economic factors. The results show that regional mortality, as a proxy for population health, and demography do not explain regional variation in visits to primary care physicians, but explain about 50% of regional variation in visits to outpatient specialists. Adjusting for socio-economic and basic supply-side factors explains 33% of the regional variation in primary physician visits, but adds nothing to explaining the variation in specialist visits. 50-67% of regional variation remains unexplained by a large number of observable regional characteristics, indicating that omitted and possibly unobserved factors contribute substantially to the regional variation. We conclude that variations in health care utilization across regions is not very well explained by underlying medical need and demand, measured by mortality, demographic and socio-economic factors.
Realizing the electric-vehicle revolution
NASA Astrophysics Data System (ADS)
Tran, Martino; Banister, David; Bishop, Justin D. K.; McCulloch, Malcolm D.
2012-05-01
Full battery electric vehicles (BEVs) have become an important policy option to mitigate climate change, but there are major uncertainties in the scale and timing of market diffusion. Although there has been substantial work showing the potential energy and climate benefits of BEVs, demand-side factors, such as consumer behaviour, are less recognized in the debate. We show the importance of assessing BEV diffusion from an integrated perspective, focusing on key interactions between technology and behaviour across different scales, including power-system demand, charging infrastructure, vehicle performance, driving patterns and individual adoption behaviour.
Against the magnanimous in medical ethics.
Kottow, M H
1990-09-01
Supererogatory acts are considered by some to be part of medicine, whereas others accept supererogation to be a gratuitous virtue, to be extolled when present, but not to be demanded. The present paper sides with those contending that medicine is duty-bound to benefit patients and that supererogation/altruism must per definition remain outside and beyond any role-description of the profession. Medical ethics should be bound by rational ethics and steer away from separatist views which grant exclusive privileges but also create excessive demands, way beyond what physicians perform or are willing and able to offer.
Smart Grid Development: Multinational Demo Project Analysis
NASA Astrophysics Data System (ADS)
Oleinikova, I.; Mutule, A.; Obushevs, A.; Antoskovs, N.
2016-12-01
This paper analyses demand side management (DSM) projects and stakeholders' experience with the aim to develop, promote and adapt smart grid tehnologies in Latvia. The research aims at identifying possible system service posibilites, including demand response (DR) and determining the appropriate market design for such type of services to be implemented at the Baltic power system level, with the cooperation of distribution system operator (DSO) and transmission system operator (TSO). This paper is prepared as an extract from the global smart grid best practices, smart solutions and business models.
Blockchain Based Decentralized Management of Demand Response Programs in Smart Energy Grids.
Pop, Claudia; Cioara, Tudor; Antal, Marcel; Anghel, Ionut; Salomie, Ioan; Bertoncini, Massimo
2018-01-09
In this paper, we investigate the use of decentralized blockchain mechanisms for delivering transparent, secure, reliable, and timely energy flexibility, under the form of adaptation of energy demand profiles of Distributed Energy Prosumers, to all the stakeholders involved in the flexibility markets (Distribution System Operators primarily, retailers, aggregators, etc.). In our approach, a blockchain based distributed ledger stores in a tamper proof manner the energy prosumption information collected from Internet of Things smart metering devices, while self-enforcing smart contracts programmatically define the expected energy flexibility at the level of each prosumer, the associated rewards or penalties, and the rules for balancing the energy demand with the energy production at grid level. Consensus based validation will be used for demand response programs validation and to activate the appropriate financial settlement for the flexibility providers. The approach was validated using a prototype implemented in an Ethereum platform using energy consumption and production traces of several buildings from literature data sets. The results show that our blockchain based distributed demand side management can be used for matching energy demand and production at smart grid level, the demand response signal being followed with high accuracy, while the amount of energy flexibility needed for convergence is reduced.
CdZnTe Image Detectors for Hard-X-Ray Telescopes
NASA Technical Reports Server (NTRS)
Chen, C. M. Hubert; Cook, Walter R.; Harrison, Fiona A.; Lin, Jiao Y. Y.; Mao, Peter H.; Schindler, Stephen M.
2005-01-01
Arrays of CdZnTe photodetectors and associated electronic circuitry have been built and tested in a continuing effort to develop focal-plane image sensor systems for hard-x-ray telescopes. Each array contains 24 by 44 pixels at a pitch of 498 m. The detector designs are optimized to obtain low power demand with high spectral resolution in the photon- energy range of 5 to 100 keV. More precisely, each detector array is a hybrid of a CdZnTe photodetector array and an application-specific integrated circuit (ASIC) containing an array of amplifiers in the same pixel pattern as that of the detectors. The array is fabricated on a single crystal of CdZnTe having dimensions of 23.6 by 12.9 by 2 mm. The detector-array cathode is a monolithic platinum contact. On the anode plane, the contact metal is patterned into the aforementioned pixel array, surrounded by a guard ring that is 1 mm wide on three sides and is 0.1 mm wide on the fourth side so that two such detector arrays can be placed side-by-side to form a roughly square sensor area with minimal dead area between them. Figure 1 shows two anode patterns. One pattern features larger pixel anode contacts, with a 30-m gap between them. The other pattern features smaller pixel anode contacts plus a contact for a shaping electrode in the form of a grid that separates all the pixels. In operation, the grid is held at a potential intermediate between the cathode and anode potentials to steer electric charges toward the anode in order to reduce the loss of charges in the inter-anode gaps. The CdZnTe photodetector array is mechanically and electrically connected to the ASIC (see Figure 2), either by use of indium bump bonds or by use of conductive epoxy bumps on the CdZnTe array joined to gold bumps on the ASIC. Hence, the output of each pixel detector is fed to its own amplifier chain.
Design of a novel, one-sided, pedal-activated wheelchair.
Lin, T-Y; Hsiao, K-H; Yao, H-W
2011-07-01
The present paper proposes the design of a novel, one-sided, pedal-activated wheelchair for patients with hemiplegia or hemiparesis. The design comprises a planetary hub transmission, which is embedded in the hub of the wheelchair, with drive, neutral, and reverse modes. The paper first discusses the structural characteristics and motion transmission of the wheelchair, and then presents the motion design of the hub transmission, followed by assembly and testing of the prototype. The results confirm that the proposed wheelchair and hub transmission can meet users' demands, thus improving comfort and independence.
Multi-time scale dynamics in power electronics-dominated power systems
NASA Astrophysics Data System (ADS)
Yuan, Xiaoming; Hu, Jiabing; Cheng, Shijie
2017-09-01
Electric power infrastructure has recently undergone a comprehensive transformation from electromagnetics to semiconductors. Such a development is attributed to the rapid growth of power electronic converter applications in the load side to realize energy conservation and on the supply side for renewable generations and power transmissions using high voltage direct current transmission. This transformation has altered the fundamental mechanism of power system dynamics, which demands the establishment of a new theory for power system control and protection. This paper presents thoughts on a theoretical framework for the coming semiconducting power systems.
Creation of backdoors in quantum communications via laser damage
NASA Astrophysics Data System (ADS)
Makarov, Vadim; Bourgoin, Jean-Philippe; Chaiwongkhot, Poompong; Gagné, Mathieu; Jennewein, Thomas; Kaiser, Sarah; Kashyap, Raman; Legré, Matthieu; Minshull, Carter; Sajeed, Shihan
2016-09-01
Practical quantum communication (QC) protocols are assumed to be secure provided implemented devices are properly characterized and all known side channels are closed. We show that this is not always true. We demonstrate a laser-damage attack capable of modifying device behavior on demand. We test it on two practical QC systems for key distribution and coin tossing, and show that newly created deviations lead to side channels. This reveals that laser damage is a potential security risk to existing QC systems, and necessitates their testing to guarantee security.
NASA Astrophysics Data System (ADS)
Furlong, Cosme; Pryputniewicz, Ryszard J.
1998-05-01
Increased demands on the performance and efficiency of mechanical components impose challenges on their engineering design and optimization, especially when new and more demanding applications must be developed in relatively short periods of time while satisfying design objectives, as well as cost and manufacturability. In addition, reliability and durability must be taken into consideration. As a consequence, effective quantitative methodologies, computational and experimental, should be applied in the study and optimization of mechanical components. Computational investigations enable parametric studies and the determination of critical engineering design conditions, while experimental investigations, especially those using optical techniques, provide qualitative and quantitative information on the actual response of the structure of interest to the applied load and boundary conditions. We discuss a hybrid experimental and computational approach for investigation and optimization of mechanical components. The approach is based on analytical, computational, and experimental resolutions methodologies in the form of computational, noninvasive optical techniques, and fringe prediction analysis tools. Practical application of the hybrid approach is illustrated with representative examples that demonstrate the viability of the approach as an effective engineering tool for analysis and optimization.
Numerical Approach for Goaf-Side Entry Layout and Yield Pillar Design in Fractured Ground Conditions
NASA Astrophysics Data System (ADS)
Jiang, Lishuai; Zhang, Peipeng; Chen, Lianjun; Hao, Zhen; Sainoki, Atsushi; Mitri, Hani S.; Wang, Qingbiao
2017-11-01
Entry driven along goaf-side (EDG), which is the development of an entry of the next longwall panel along the goaf-side and the isolation of the entry from the goaf with a small-width yield pillar, has been widely employed in China over the past several decades . The width of such a yield pillar has a crucial effect on EDG layout in terms of the ground control, isolation effect and resource recovery rate. Based on a case study, this paper presents an approach for evaluating, designing and optimizing EDG and yield pillar by considering the results from numerical simulations and field practice. To rigorously analyze the ground stability, the numerical study begins with the simulation of goaf-side stress and ground conditions. Four global models with identical conditions, except for the width of the yield pillar, are built, and the effect of pillar width on ground stability is investigated by comparing aspects of stress distribution, failure propagation, and displacement evolution during the entire service life of the entry. Based on simulation results, the isolation effect of the pillar acquired from field practice is also considered. The suggested optimal yield pillar design is validated using a field test in the same mine. Thus, the presented numerical approach provides references and can be utilized for the evaluation, design and optimization of EDG and yield pillars under similar geological and geotechnical circumstances.
NASA Astrophysics Data System (ADS)
Bauer, Sebastian; Suchaneck, Andre; Puente León, Fernando
2014-01-01
Depending on the actual battery temperature, electrical power demands in general have a varying impact on the life span of a battery. As electrical energy provided by the battery is needed to temper it, the question arises at which temperature which amount of energy optimally should be utilized for tempering. Therefore, the objective function that has to be optimized contains both the goal to maximize life expectancy and to minimize the amount of energy used for obtaining the first goal. In this paper, Pontryagin's maximum principle is used to derive a causal control strategy from such an objective function. The derivation of the causal strategy includes the determination of major factors that rule the optimal solution calculated with the maximum principle. The optimization is calculated offline on a desktop computer for all possible vehicle parameters and major factors. For the practical implementation in the vehicle, it is sufficient to have the values of the major factors determined only roughly in advance and the offline calculation results available. This feature sidesteps the drawback of several optimization strategies that require the exact knowledge of the future power demand. The resulting strategy's application is not limited to batteries in electric vehicles.
NASA Astrophysics Data System (ADS)
Chu, J.; Zhang, C.; Fu, G.; Li, Y.; Zhou, H.
2015-08-01
This study investigates the effectiveness of a sensitivity-informed method for multi-objective operation of reservoir systems, which uses global sensitivity analysis as a screening tool to reduce computational demands. Sobol's method is used to screen insensitive decision variables and guide the formulation of the optimization problems with a significantly reduced number of decision variables. This sensitivity-informed method dramatically reduces the computational demands required for attaining high-quality approximations of optimal trade-off relationships between conflicting design objectives. The search results obtained from the reduced complexity multi-objective reservoir operation problems are then used to pre-condition the full search of the original optimization problem. In two case studies, the Dahuofang reservoir and the inter-basin multi-reservoir system in Liaoning province, China, sensitivity analysis results show that reservoir performance is strongly controlled by a small proportion of decision variables. Sensitivity-informed dimension reduction and pre-conditioning are evaluated in their ability to improve the efficiency and effectiveness of multi-objective evolutionary optimization. Overall, this study illustrates the efficiency and effectiveness of the sensitivity-informed method and the use of global sensitivity analysis to inform dimension reduction of optimization problems when solving complex multi-objective reservoir operation problems.
A protein-dependent side-chain rotamer library.
Bhuyan, Md Shariful Islam; Gao, Xin
2011-12-14
Protein side-chain packing problem has remained one of the key open problems in bioinformatics. The three main components of protein side-chain prediction methods are a rotamer library, an energy function and a search algorithm. Rotamer libraries summarize the existing knowledge of the experimentally determined structures quantitatively. Depending on how much contextual information is encoded, there are backbone-independent rotamer libraries and backbone-dependent rotamer libraries. Backbone-independent libraries only encode sequential information, whereas backbone-dependent libraries encode both sequential and locally structural information. However, side-chain conformations are determined by spatially local information, rather than sequentially local information. Since in the side-chain prediction problem, the backbone structure is given, spatially local information should ideally be encoded into the rotamer libraries. In this paper, we propose a new type of backbone-dependent rotamer library, which encodes structural information of all the spatially neighboring residues. We call it protein-dependent rotamer libraries. Given any rotamer library and a protein backbone structure, we first model the protein structure as a Markov random field. Then the marginal distributions are estimated by the inference algorithms, without doing global optimization or search. The rotamers from the given library are then re-ranked and associated with the updated probabilities. Experimental results demonstrate that the proposed protein-dependent libraries significantly outperform the widely used backbone-dependent libraries in terms of the side-chain prediction accuracy and the rotamer ranking ability. Furthermore, without global optimization/search, the side-chain prediction power of the protein-dependent library is still comparable to the global-search-based side-chain prediction methods.
Centralized and Decentralized Control for Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lu, Shuai; Samaan, Nader A.; Diao, Ruisheng
2011-04-29
Demand response has been recognized as an essential element of the smart grid. Frequency response, regulation and contingency reserve functions performed traditionally by generation resources are now starting to involve demand side resources. Additional benefits from demand response include peak reduction and load shifting, which will defer new infrastructure investment and improve generator operation efficiency. Technical approaches designed to realize these functionalities can be categorized into centralized control and decentralized control, depending on where the response decision is made. This paper discusses these two control philosophies and compares their relative advantages and disadvantages in terms of delay time, predictability, complexity,more » and reliability. A distribution system model with detailed household loads and controls is built to demonstrate the characteristics of the two approaches. The conclusion is that the promptness and reliability of decentralized control should be combined with the predictability and simplicity of centralized control to achieve the best performance of the smart grid.« less
Price sensitive demand with random sales price - a newsboy problem
NASA Astrophysics Data System (ADS)
Sankar Sana, Shib
2012-03-01
Up to now, many newsboy problems have been considered in the stochastic inventory literature. Some assume that stochastic demand is independent of selling price (p) and others consider the demand as a function of stochastic shock factor and deterministic sales price. This article introduces a price-dependent demand with stochastic selling price into the classical Newsboy problem. The proposed model analyses the expected average profit for a general distribution function of p and obtains an optimal order size. Finally, the model is discussed for various appropriate distribution functions of p and illustrated with numerical examples.
ANSYS-based birefringence property analysis of side-hole fiber induced by pressure and temperature
NASA Astrophysics Data System (ADS)
Zhou, Xinbang; Gong, Zhenfeng
2018-03-01
In this paper, we theoretically investigate the influences of pressure and temperature on the birefringence property of side-hole fibers with different shapes of holes using the finite element analysis method. A physical mechanism of the birefringence of the side-hole fiber is discussed with the presence of different external pressures and temperatures. The strain field distribution and birefringence values of circular-core, rectangular-core, and triangular-core side-hole fibers are presented. Our analysis shows the triangular-core side-hole fiber has low temperature sensitivity which weakens the cross sensitivity of temperature and strain. Additionally, an optimized structure design of the side-hole fiber is presented which can be used for the sensing application.
MONITOR THE PHOTOVOLTAIC (PV) SYSTEM ON THE NCC ROOFTOP
This study will investigate the pollution emission reduction and demand-side management potential of a
100 kW PV system located on the roof of the National Computer Center (NCC). Standardized instrumentation to measure meteorological and PV system performance variables will b...
7 CFR 1717.852 - Financing purposes.
Code of Federal Regulations, 2011 CFR
2011-01-01
... and energy conservation, and on-grid and off-grid renewable energy systems; (2) The purchase..., except: (i) Certain load-management equipment (see 7 CFR 1710.251(c)); (ii) Renewable energy systems and RUS-approved programs of demand side management and energy conservation; and (iii) As determined by...
The Basic Economics of CD-ROM Pricing.
ERIC Educational Resources Information Center
Erkkila, John E.
1991-01-01
This explanation of how the basic economic model of pricing applies to the CD-ROM industry considers the supply and demand sides of the market and compares three distinct pricing strategies: (1) pricing to maximize profits; (2) average cost pricing; and (3) marginal cost pricing. (EAM)
Green, Linda V; Savin, Sergei; Lu, Yina
2013-01-01
Most existing estimates of the shortage of primary care physicians are based on simple ratios, such as one physician for every 2,500 patients. These estimates do not consider the impact of such ratios on patients' ability to get timely access to care. They also do not quantify the impact of changing patient demographics on the demand side and alternative methods of delivering care on the supply side. We used simulation methods to provide estimates of the number of primary care physicians needed, based on a comprehensive analysis considering access, demographics, and changing practice patterns. We show that the implementation of some increasingly popular operational changes in the ways clinicians deliver care-including the use of teams or "pods," better information technology and sharing of data, and the use of nonphysicians-have the potential to offset completely the increase in demand for physician services while improving access to care, thereby averting a primary care physician shortage.
Does Information Matter? The Effect of the Meth Project on Meth Use among Youths*
Anderson, D. Mark
2010-01-01
Are demand-side interventions effective at curbing drug use? To the extent demand-side programs are successful, their cost effectiveness can be appealing from a policy perspective. Established in 2005, the Montana Meth Project (MMP) employs a graphic advertising campaign to deter meth use among teens. Due to the MMP’s apparent success, seven other states have adopted Meth Project campaigns. Using data from the Youth Risk Behavior Surveys (YRBS), this paper investigates whether the MMP reduced methamphetamine use among Montana’s youth. When accounting for a preexisting downward trend in meth use, effects on meth use are statistically indistinguishable from zero. These results are robust to using related changes of meth use among individuals without exposure to the campaign as controls in a difference-in-difference framework. A complementary analysis of treatment admissions data from the Treatment Episode Data Set (TEDS) confirms the MMP has had no discernable impact on meth use. PMID:20638737
Does information matter? The effect of the Meth Project on meth use among youths.
Anderson, D Mark
2010-09-01
Are demand-side interventions effective at curbing drug use? To the extent demand-side programs are successful, their cost effectiveness can be appealing from a policy perspective. Established in 2005, the Montana Meth Project (MMP) employs a graphic advertising campaign to deter meth use among teens. Due to the MMP's apparent success, seven other states have adopted Meth Project campaigns. Using data from the Youth Risk Behavior Surveys (YRBS), this paper investigates whether the MMP reduced methamphetamine use among Montana's youth. When accounting for a preexisting downward trend in meth use, effects on meth use are statistically indistinguishable from zero. These results are robust to using related changes of meth use among individuals without exposure to the campaign as controls in a difference-in-difference framework. A complementary analysis of treatment admissions data from the Treatment Episode Data Set (TEDS) confirms the MMP has had no discernable impact on meth use. Copyright 2010 Elsevier B.V. All rights reserved.