Self-Selection, Optimal Income Taxation, and Redistribution
ERIC Educational Resources Information Center
Amegashie, J. Atsu
2009-01-01
The author makes a pedagogical contribution to optimal income taxation. Using a very simple model adapted from George A. Akerlof (1978), he demonstrates a key result in the approach to public economics and welfare economics pioneered by Nobel laureate James Mirrlees. He shows how incomplete information, in addition to the need to preserve…
Conservation of a fishery through optimal taxation: a dynamic reaction model
NASA Astrophysics Data System (ADS)
Kar, Tapan Kumar
2005-03-01
The present paper deals with the problem of selective harvesting in a ratio-dependent predator-prey fishery in which both the predator and prey obey the logistic law of growth. To protect fish population from over exploitation a control instrument tax is imposed. The existence of its steady states and their stability are studied. The problem of optimal taxation policy is then solved by using Pontryagin's maximal principle. Finally some numerical examples are taken to illustrate the results.
Trumpy, T.
1995-12-01
More efficient use of energy resources can be promoted by various regulatory means, i.e., taxation, subsidies, and pricing. Various incentives can be provided by income and revenue tax breaks-deductible energy audit fees, energy saving investment credits, breaks for energy saving entrepreneurs, and energy savings accounts run through utility accounts. Value added and excise taxes can also be adjusted to reward energy saving investments and energy saving entrepreneurial activity. Incentives can be provided in the form of cash refunds, including trade-in-and-scrap programs and reimbursements or subsidies on audit costs and liability insurance. Pricing incentives include lower rates for less energy use, prepayment of deposit related to peak load use, electronically dispatched multiple tariffs, savings credits based on prior peak use, and subsidized {open_quotes}leasing{close_quotes} of more efficient appliances and lights. Credits, with an emphasis on pooling small loans, and 5-year energy savings contracts are also discussed.
Wirl, F. )
1994-01-01
The literature on energy and carbon taxes is by and large concerned about the derivation of (globally) efficient strategies. In contrast, this paper considers the dynamic interactions between cartelized energy suppliers and a consumers' government that collectively taxes energy carriers for Pigouvian motives. Two different kinds of external costs are associated with energy consumption: flow (e.g., acid rain) and stock externalities (e.g., global warming). The dynamic interactions between a consumers' government and a producers' cartel are modeled as a differential game with a subgame perfect Nash equilibrium in linear and nonlinear Markov strategies. The major implications are that the nonlinear solutions are Pareto-inferior to the linear strategies and energy suppliers may preempt energy taxation and thereby may raise the price at front; however, this effect diminishes over time because the producers' price declines, while taxes increase. 22 refs., 5 figs., 1 tab.
Influence of simplified nutrition labeling and taxation on laboratory energy intake in adults.
Temple, Jennifer L; Johnson, Karena M; Archer, Kelli; Lacarte, Allison; Yi, Christina; Epstein, Leonard H
2011-08-01
The purpose of these studies was to test the hypotheses that simplified nutrition labeling and taxation alter food selection and intake. In Experiment 1, participants consumed lunch in the laboratory three times with no labels, standard nutrition labels, or traffic light diet labels at each visit. In Experiment 2, participants were given $6.00 with which to purchase lunch in the laboratory twice with standard pricing on one visit and a 25% tax on "red" foods on another visit. Participants received a brief education session on the labeling systems being used. Total energy intake and energy intake and number of foods purchased from each traffic light category were measured. Nutrition labeling decreased energy intake in lean females, but had no effect in men or in obese females. Traffic light labels increased consumption of "green" foods and decreased consumption of "red" foods. Taxation decreased the purchasing of "red" foods in obese, but not non-obese participants. There were no interactions between taxation and simplified nutrition labeling. Although generalization to real-world purchasing and consumption is limited by the laboratory study design, our findings suggests that taking multiple, simultaneous approaches to reduce energy intake may have the greatest impact on food purchases and/or nutrient consumption. PMID:21569807
Energy use and taxation policy in the New Zealand car fleet
Not Available
1984-02-01
The report describes the composition of the New Zealand car fleet and the relationship between design factors, fleet composition, vehicle useage and fuel consumption. The indirect energy content of the vehicle and roadway are discussed. Existing and potential Government policy instruments for promoting fuel economy in the car fleet are discussed and evaluated. The report conclusions favor flat rate sales tax on vehicles regardless of engine size together with an appropriate level of petrol tax in preference to taxation that varies with vehicle size or engine capacity. A review of hire purchase regulations is proposed. Prior to publication of this report the Industries Development Commission Plan for the motor vehicle industry was released which proposes changes to the tariff, taxation and credit purchase regime applying to motor vehicles. These changes are summarized.
ENERGY PRODUCTION AND RESIDENTIAL HEATING: TAXATION, SUBSIDIES, AND COMPARATIVE COSTS
This analysis is in support of the Ohio River Basin Energy Study (ORBES), a multidisciplinary policy research program supported by the Environmental Protection Agency. It examines the effect of economic incentives on public and private decisions affecting energy production and us...
Olken, Benjamin A.; Singhal, Monica
2011-01-01
Informal payments are a frequently overlooked source of local public finance in developing countries. We use microdata from ten countries to establish stylized facts on the magnitude, form, and distributional implications of this “informal taxation.” Informal taxation is widespread, particularly in rural areas, with substantial in-kind labor payments. The wealthy pay more, but pay less in percentage terms, and informal taxes are more regressive than formal taxes. Failing to include informal taxation underestimates household tax burdens and revenue decentralization in developing countries. We discuss various explanations for and implications of these observed stylized facts. PMID:22199993
NASA Astrophysics Data System (ADS)
Lachapelle, Erick
differential rates of carbon-energy taxation. By opening up the ideological space to a broader spectrum of "green" parties, I argue that PR systems create a favourable institutional context within which higher rates of carbon-energy taxation become politically possible. After specifying a key causal mechanism within different types of electoral systems -- the seat-vote elasticity -- I argue further that, voters in disproportional systems actually have more leverage over politicians, and that an increase in environmental voting can have an impact on rates of carbon energy taxation, even in the absence of PR. While the accession to power of green political parties in PR systems is more likely to lead to higher rates of carbon energy taxation, voting for green parties in highly disproportional systems creates incentives for other parties to adopt "green" policies, leading to a similar outcome. In this way, the effect of green votes and green seats will have the opposite effect on policy according to the type of electoral system in use.
Nuclear Energy Density Optimization
Kortelainen, Erno M; Lesinski, Thomas; More, J.; Nazarewicz, W.; Sarich, J.; Schunck, N.; Stoitsov, M. V.; Wild, S.
2010-01-01
We carry out state-of-the-art optimization of a nuclear energy density of Skyrme type in the framework of the Hartree-Fock-Bogoliubov (HFB) theory. The particle-hole and particle-particle channels are optimized simultaneously, and the experimental data set includes both spherical and deformed nuclei. The new model-based, derivative-free optimization algorithm used in this work has been found to be significantly better than standard optimization methods in terms of reliability, speed, accuracy, and precision. The resulting parameter set UNEDFpre results in good agreement with experimental masses, radii, and deformations and seems to be free of finite-size instabilities. An estimate of the reliability of the obtained parameterization is given, based on standard statistical methods. We discuss new physics insights offered by the advanced covariance analysis.
Zhou, Zhi; de Bedout, Juan Manuel; Kern, John Michael; Biyik, Emrah; Chandra, Ramu Sharat
2013-01-22
A system for optimizing customer utility usage in a utility network of customer sites, each having one or more utility devices, where customer site is communicated between each of the customer sites and an optimization server having software for optimizing customer utility usage over one or more networks, including private and public networks. A customer site model for each of the customer sites is generated based upon the customer site information, and the customer utility usage is optimized based upon the customer site information and the customer site model. The optimization server can be hosted by an external source or within the customer site. In addition, the optimization processing can be partitioned between the customer site and an external source.
Taxation and the American Indian
ERIC Educational Resources Information Center
Brunt, David
1973-01-01
The article explores American Indian tribal rights to tax exemptions and self-imposed taxation; general recommendations on possible tribal tax alternatives; and evaluation of the probable economic effect of taxation. (FF)
Integrated solar energy system optimization
NASA Astrophysics Data System (ADS)
Young, S. K.
1982-11-01
The computer program SYSOPT, intended as a tool for optimizing the subsystem sizing, performance, and economics of integrated wind and solar energy systems, is presented. The modular structure of the methodology additionally allows simulations when the solar subsystems are combined with conventional technologies, e.g., a utility grid. Hourly energy/mass flow balances are computed for interconnection points, yielding optimized sizing and time-dependent operation of various subsystems. The program requires meteorological data, such as insolation, diurnal and seasonal variations, and wind speed at the hub height of a wind turbine, all of which can be taken from simulations like the TRNSYS program. Examples are provided for optimization of a solar-powered (wind turbine and parabolic trough-Rankine generator) desalinization plant, and a design analysis for a solar powered greenhouse.
Integrated Energy System Dispatch Optimization
Firestone, Ryan; Stadler, Michael; Marnay, Chris
2006-06-16
On-site cogeneration of heat and electricity, thermal and electrical storage, and curtailing/rescheduling demand options are often cost-effective to commercial and industrial sites. This collection of equipment and responsive consumption can be viewed as an integrated energy system(IES). The IES can best meet the sites cost or environmental objectives when controlled in a coordinated manner. However, continuously determining this optimal IES dispatch is beyond the expectations for operators of smaller systems. A new algorithm is proposed in this paper to approximately solve the real-time dispatch optimization problem for a generic IES containing an on-site cogeneration system subject to random outages, limited curtailment opportunities, an intermittent renewable electricity source, and thermal storage. An example demonstrates how this algorithm can be used in simulation to estimate the value of IES components.
The Influence of the Income Taxation on the Agent Savings
NASA Astrophysics Data System (ADS)
Marinescu, Daniela; Ramniceanu, Ioana; Marin, Dumitru
2009-08-01
In the model we will analyze the influence of the taxation change on choosing the optimal portfolio. We will prove that when the absolute index of the risk aversion is decreasing the amount invested in the risky active increase as a result of the income and substitution effects.
Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-01-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Code of Federal Regulations, 2010 CFR
2010-07-01
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Design criteria for optimal photosynthetic energy conversion
NASA Astrophysics Data System (ADS)
Fingerhut, Benjamin P.; Zinth, Wolfgang; de Vivie-Riedle, Regina
2008-12-01
Photochemical solar energy conversion is considered as an alternative of clean energy. For future light converting nano-machines photosynthetic reaction centers are used as prototypes optimized during evolution. We introduce a reaction scheme for global optimization and simulate the ultrafast charge separation in photochemical energy conversion. Multiple molecular charge carriers are involved in this process and are linked by Marcus-type electron transfer. In combination with evolutionary algorithms, we unravel the biological strategies for high quantum efficiency in photosynthetic reaction centers and extend these concepts to the design of artificial photochemical devices for energy conversion.
Renewable Energy Cost Optimization Spreadsheet
2007-12-31
The Software allow users to determine the optimum combination of renewable energy technologies to minimize life cycle cost for a facility by employing various algorithms which calculate initial and operating cost, energy delivery, and other attributes associated with each technology as a function of size.
Vibration energy harvester optimization using artificial intelligence
NASA Astrophysics Data System (ADS)
Hadas, Z.; Ondrusek, C.; Kurfurst, J.; Singule, V.
2011-06-01
This paper deals with an optimization study of a vibration energy harvester. This harvester can be used as autonomous source of electrical energy for remote or wireless applications, which are placed in environment excited by ambient mechanical vibrations. The ambient energy of vibrations is usually on very low level but the harvester can be used as alternative source of energy for electronic devices with an expected low level of power consumption of several mW. The optimized design of the vibration energy harvester was based on previous development and the sensitivity of harvester design was improved for effective harvesting from mechanical vibrations in aeronautic applications. The vibration energy harvester is a mechatronic system which generates electrical energy from ambient vibrations due to precision tuning up generator parameters. The optimization study for maximization of harvested power or minimization of volume and weight are the main goals of our development. The optimization study of such complex device is complicated therefore artificial intelligence methods can be used for tuning up optimal harvester parameters.
Pyroelectric energy conversion: optimization principles.
Sebald, Gael; Lefeuvre, Elie; Guyomar, Daniel
2008-03-01
In the framework of microgenerators, we present in this paper the key points for energy harvesting from temperature using ferroelectric materials. Thermoelectric devices profit from temperature spatial gradients, whereas ferroelectric materials require temporal fluctuation of temperature, thus leading to different applications targets. Ferroelectric materials may harvest perfectly the available thermal energy whatever the materials properties (limited by Carnot conversion efficiency) whereas thermoelectric material's efficiency is limited by materials properties (ZT figure of merit). However, it is shown that the necessary electric fields for Carnot cycles are far beyond the breakdown limit of bulk ferroelectric materials. Thin films may be an excellent solution for rising up to ultra-high electric fields and outstanding efficiency. Different thermodynamic cycles are presented in the paper: principles, advantages, and drawbacks. Using the Carnot cycle, the harvested energy would be independent of materials properties. However, using more realistic cycles, the energy conversion effectiveness remains dependent on the materials properties as discussed in the paper. A particular coupling factor is defined to quantify and check the effectiveness of pyroelectric energy harvesting. It is defined similarly to an electromechanical coupling factor as k2=p2theta0/(epsilontheta33cE), where p, theta0, epsilontheta33, cE are pyroelectric coefficient, maximum working temperature, dielectric permittivity, and specific heat, respectively. The importance of the electrothermal coupling factor is shown and discussed as an energy harvesting figure of merit. It gives the effectiveness of all techniques of energy harvesting (except the Carnot cycle). It is finally shown that we could reach very high efficiency using 1110.75Pb(Mg1/3Nb2/3)-0.25PbTiO3 single crystals and synchronized switch harvesting on inductor (almost 50% of Carnot efficiency). Finally, practical implementation key
Optimizing New Dark Energy Experiments
Tyson, J. Anthony
2013-08-26
Next generation “Stage IV” dark energy experiments under design during this grant, and now under construction, will enable the determination of the properties of dark energy and dark matter to unprecedented precision using multiple complementary probes. The most pressing challenge in these experiments is the characterization and understanding of the systematic errors present within any given experimental configuration and the resulting impact on the accuracy of our constraints on dark energy physics. The DETF and the P5 panel in their reports recommended “Expanded support for ancillary measurements required for the long-term program and for projects that will improve our understanding and reduction of the dominant systematic measurement errors.” Looking forward to the next generation Stage IV experiments we have developed a program to address the most important potential systematic errors within these experiments. Using data from current facilities it has been feasible and timely to undertake a detailed investigation of the systematic errors. In this DOE grant we studied of the source and impact of the dominant systematic effects in dark energy measurements, and developed new analysis tools and techniques to minimize their impact. Progress under this grant is briefly reviewed in this technical report. This work was a necessary precursor to the coming generations of wide-deep probes of the nature of dark energy and dark matter. The research has already had an impact on improving the efficiencies of all Stage III and IV dark energy experiments.
Analysis and Optimization of Building Energy Consumption
NASA Astrophysics Data System (ADS)
Chuah, Jun Wei
Energy is one of the most important resources required by modern human society. In 2010, energy expenditures represented 10% of global gross domestic product (GDP). By 2035, global energy consumption is expected to increase by more than 50% from current levels. The increased pace of global energy consumption leads to significant environmental and socioeconomic issues: (i) carbon emissions, from the burning of fossil fuels for energy, contribute to global warming, and (ii) increased energy expenditures lead to reduced standard of living. Efficient use of energy, through energy conservation measures, is an important step toward mitigating these effects. Residential and commercial buildings represent a prime target for energy conservation, comprising 21% of global energy consumption and 40% of the total energy consumption in the United States. This thesis describes techniques for the analysis and optimization of building energy consumption. The thesis focuses on building retrofits and building energy simulation as key areas in building energy optimization and analysis. The thesis first discusses and evaluates building-level renewable energy generation as a solution toward building energy optimization. The thesis next describes a novel heating system, called localized heating. Under localized heating, building occupants are heated individually by directed radiant heaters, resulting in a considerably reduced heated space and significant heating energy savings. To support localized heating, a minimally-intrusive indoor occupant positioning system is described. The thesis then discusses occupant-level sensing (OLS) as the next frontier in building energy optimization. OLS captures the exact environmental conditions faced by each building occupant, using sensors that are carried by all building occupants. The information provided by OLS enables fine-grained optimization for unprecedented levels of energy efficiency and occupant comfort. The thesis also describes a retrofit
Quad-rotor flight path energy optimization
NASA Astrophysics Data System (ADS)
Kemper, Edward
Quad-Rotor unmanned areal vehicles (UAVs) have been a popular area of research and development in the last decade, especially with the advent of affordable microcontrollers like the MSP 430 and the Raspberry Pi. Path-Energy Optimization is an area that is well developed for linear systems. In this thesis, this idea of path-energy optimization is extended to the nonlinear model of the Quad-rotor UAV. The classical optimization technique is adapted to the nonlinear model that is derived for the problem at hand, coming up with a set of partial differential equations and boundary value conditions to solve these equations. Then, different techniques to implement energy optimization algorithms are tested using simulations in Python. First, a purely nonlinear approach is used. This method is shown to be computationally intensive, with no practical solution available in a reasonable amount of time. Second, heuristic techniques to minimize the energy of the flight path are tested, using Ziegler-Nichols' proportional integral derivative (PID) controller tuning technique. Finally, a brute force look-up table based PID controller is used. Simulation results of the heuristic method show that both reliable control of the system and path-energy optimization are achieved in a reasonable amount of time.
An optimal renewable energy mix for Indonesia
NASA Astrophysics Data System (ADS)
Leduc, Sylvain; Patrizio, Piera; Yowargana, Ping; Kraxner, Florian
2016-04-01
Indonesia has experienced a constant increase of the use of petroleum and coal in the power sector, while the share of renewable sources has remained stable at 6% of the total energy production during the last decade. As its domestic energy demand undeniably continues to grow, Indonesia is committed to increase the production of renewable energy. Mainly to decrease its dependency on fossil fuel-based resources, and to decrease the anthropogenic emissions, the government of Indonesia has established a 23 percent target for renewable energy by 2025, along with a 100 percent electrification target by 2020 (the current rate is 80.4 percent). In that respect, Indonesia has abundant resources to meet these targets, but there is - inter alia - a lack of proper integrated planning, regulatory support, investment, distribution in remote areas of the Archipelago, and missing data to back the planning. To support the government of Indonesia in its sustainable energy system planning, a geographic explicit energy modeling approach is applied. This approach is based on the energy systems optimization model BeWhere, which identifies the optimal location of energy conversion sites based on the minimization of the costs of the supply chain. The model will incorporate the existing fossil fuel-based infrastructures, and evaluate the optimal costs, potentials and locations for the development of renewable energy technologies (i.e., wind, solar, hydro, biomass and geothermal based technologies), as well as the development of biomass co-firing in existing coal plants. With the help of the model, an optimally adapted renewable energy mix - vis-à-vis the competing fossil fuel based resources and applicable policies in order to promote the development of those renewable energy technologies - will be identified. The development of the optimal renewable energy technologies is carried out with special focus on nature protection and cultural heritage areas, where feedstock (e.g., biomass
Sovereignty: The Navajo Nation and Taxation.
ERIC Educational Resources Information Center
Benson, Michael
Contending that it is wrong for the Navajo Government to continue to neglect its citizens by not implementing a taxation program, this monograph is written to generate interest in and discussion of a taxation program and the Navajo Tax Commission, created in 1974. Specifically, this booklet presents basic information re: the financing of the…
Life cycle optimization of building energy systems
NASA Astrophysics Data System (ADS)
Osman, Ayat; Norman, Bryan; Ries, Robert
2008-02-01
A life cycle optimization model intended to potentially reduce the environmental impacts of energy use in commercial buildings is presented. A combination of energy simulation, life cycle assessment, and operations research techniques are used to develop the model. In addition to conventional energy systems, such as the electric grid and a gas boiler, cogeneration systems which concurrently generate power and heat are investigated as an alternative source of energy. Cogeneration systems appeared to be an attractive alternative to conventional systems when considering life cycle environmental criteria. Internal combustion engine and microturbine (MT) cogeneration systems resulted in a reduction of up to 38% in global warming potential compared with conventional systems, while solid oxide fuel cell and MT cogeneration systems resulted in a reduction of up to 94% in tropospheric ozone precursor potential (TOPP). Results include a Pareto-optimal frontier between reducing costs and reducing the selected environmental indicators.
Energy optimization in mobile sensor networks
NASA Astrophysics Data System (ADS)
Yu, Shengwei
Mobile sensor networks are considered to consist of a network of mobile robots, each of which has computation, communication and sensing capabilities. Energy efficiency is a critical issue in mobile sensor networks, especially when mobility (i.e., locomotion control), routing (i.e., communications) and sensing are unique characteristics of mobile robots for energy optimization. This thesis focuses on the problem of energy optimization of mobile robotic sensor networks, and the research results can be extended to energy optimization of a network of mobile robots that monitors the environment, or a team of mobile robots that transports materials from stations to stations in a manufacturing environment. On the energy optimization of mobile robotic sensor networks, our research focuses on the investigation and development of distributed optimization algorithms to exploit the mobility of robotic sensor nodes for network lifetime maximization. In particular, the thesis studies these five problems: 1. Network-lifetime maximization by controlling positions of networked mobile sensor robots based on local information with distributed optimization algorithms; 2. Lifetime maximization of mobile sensor networks with energy harvesting modules; 3. Lifetime maximization using joint design of mobility and routing; 4. Optimal control for network energy minimization; 5. Network lifetime maximization in mobile visual sensor networks. In addressing the first problem, we consider only the mobility strategies of the robotic relay nodes in a mobile sensor network in order to maximize its network lifetime. By using variable substitutions, the original problem is converted into a convex problem, and a variant of the sub-gradient method for saddle-point computation is developed for solving this problem. An optimal solution is obtained by the method. Computer simulations show that mobility of robotic sensors can significantly prolong the lifetime of the whole robotic sensor network while
Energy optimization of water distribution systems
1994-09-01
Energy costs associated with pumping treated water into the distribution system and boosting water pressures where necessary is one of the largest expenditures in the operating budget of a municipality. Due to the size and complexity of Detroit`s water transmission system, an energy optimization project has been developed to better manage the flow of water in the distribution system in an attempt to reduce these costs.
Optimal Low Energy Earth-Moon Transfers
NASA Technical Reports Server (NTRS)
Griesemer, Paul Ricord; Ocampo, Cesar; Cooley, D. S.
2010-01-01
The optimality of a low-energy Earth-Moon transfer is examined for the first time using primer vector theory. An optimal control problem is formed with the following free variables: the location, time, and magnitude of the transfer insertion burn, and the transfer time. A constraint is placed on the initial state of the spacecraft to bind it to a given initial orbit around a first body, and on the final state of the spacecraft to limit its Keplerian energy with respect to a second body. Optimal transfers in the system are shown to meet certain conditions placed on the primer vector and its time derivative. A two point boundary value problem containing these necessary conditions is created for use in targeting optimal transfers. The two point boundary value problem is then applied to the ballistic lunar capture problem, and an optimal trajectory is shown. Additionally, the ballistic lunar capture trajectory is examined to determine whether one or more additional impulses may improve on the cost of the transfer.
Energy accounting and optimization for mobile systems
NASA Astrophysics Data System (ADS)
Dong, Mian
Energy accounting determines how much a software process contributes to the total system energy consumption. It is the foundation for evaluating software and has been widely used by operating system based energy management. While various energy accounting policies have been tried, there is no known way to evaluate them directly simply because it is hard to track every hardware use by software in a heterogeneous multi-core system like modern smartphones and tablets. In this thesis, we provide the ground truth for energy accounting based on multi-player game theory and offer the first evaluation of existing energy accounting policies, revealing their important flaws. The proposed ground truth is based on Shapley value, a single value solution to multi-player games of which four axiomatic properties are natural and self-evident to energy accounting. To obtain the Shapley value-based ground truth, one only needs to know if a process is active during the time under question and the system energy consumption during the same time. We further provide a utility optimization formulation of energy management and show, surprisingly, that energy accounting does not matter for existing energy management solutions that control the energy use of a process by giving it an energy budget, or budget based energy management (BEM). We show an optimal energy management (OEM) framework can always outperform BEM. While OEM does not require any form of energy accounting, it is related to Shapley value in that both require the system energy consumption for all possible combination of processes under question. We provide a novel system solution that meet this requirement by acquiring system energy consumption in situ for an OS scheduler period, i.e.,10 ms. We report a prototype implementation of both Shapley value-based energy accounting and OEM based scheduling. Using this prototype and smartphone workload, we experimentally demonstrate how erroneous existing energy accounting policies can
Lead Optimization Mapper: Automating free energy calculations for lead optimization
Liu, Shuai; Wu, Yujie; Lin, Teng; Abel, Robert; Redmann, Jonathan P.; Summa, Christopher M.; Jaber, Vivian R.; Lim, Nathan M.; Mobley, David L.
2013-01-01
Alchemical free energy calculations hold increasing promise as an aid to drug discovery efforts. However, applications of these techniques in discovery projects have been relatively few, partly because of the difficulty of planning and setting up calculations. Here, we introduce Lead Optimization Mapper, LOMAP, an automated algorithm to plan efficient relative free energy calculations between potential ligands within a substantial library of perhaps hundreds of compounds. In this approach, ligands are first grouped by structural similarity primarily based on the size of a (loosely defined) maximal common substructure, and then calculations are planned within and between sets of structurally related compounds. An emphasis is placed on ensuring that relative free energies can be obtained between any pair of compounds without combining the results of too many different relative free energy calculations (to avoid accumulation of error) and by providing some redundancy to allow for the possibility of error and consistency checking and provide some insight into when results can be expected to be unreliable. The algorithm is discussed in detail and a Python implementation, based on both Schrödinger's and OpenEye's APIs, has been made available freely under the BSD license. PMID:24072356
Computational design and optimization of energy materials
NASA Astrophysics Data System (ADS)
Chan, Maria
The use of density functional theory (DFT) to understand and improve energy materials for diverse applications - including energy storage, thermal management, catalysis, and photovoltaics - is widespread. The further step of using high throughput DFT calculations to design materials and has led to an acceleration in materials discovery and development. Due to various limitations in DFT, including accuracy and computational cost, however, it is important to leverage effective models and, in some cases, experimental information to aid the design process. In this talk, I will discuss efforts in design and optimization of energy materials using a combination of effective models, DFT, machine learning, and experimental information.
Cache Energy Optimization Techniques For Modern Processors
Mittal, Sparsh
2013-01-01
and veterans in the field of cache power management. It will help graduate students, CAD tool developers and designers in understanding the need of energy efficiency in modern computing systems. Further, it will be useful for researchers in gaining insights into algorithms and techniques for micro-architectural and system-level energy optimization using dynamic cache reconfiguration. We sincerely believe that the ``food for thought'' presented in this book will inspire the readers to develop even better ideas for designing ``green'' processors of tomorrow.
Optimal energy growth in swept Hiemenz flow
NASA Astrophysics Data System (ADS)
Guegan, Alan; Huerre, Patrick; Schmid, Peter
2006-11-01
It has been shown in Gu'egan, Schmid & Huerre 2006 that the kinetic energy of optimal G"ortler-H"ammerlin (GH) perturbations in swept Hiemenz flow can be transiently amplified by two orders of magnitude at Reynolds numbers ranging from 400 to 1000 and spanwise wavenumbers from 0.1 to 0.5. In this configuration an array of counter-rotating chordwise vortices is compressed by the spanwise shear, as in the well-known Orr mechanism. We show that stronger transient growth can be achieved when the GH assumption is relaxed. In this case the optimal initial perturbation consists in vorticity sheets stacked in the chordwise direction, at a small angle from the symmetry plane of the base flow. Although the spatial structure of the GH perturbations is lost, wall-normal-spanwise plane cuts show that the amplification mechanism is mostly unchanged. The GH assumption thus provides a reasonably good estimate for transient energy amplification levels in swept Hiemenz flow. Extension of this analysis to the spatial growth problem is under way and preliminary results will be shown.
A Method for Determining Optimal Residential Energy Efficiency Packages
Polly, B.; Gestwick, M.; Bianchi, M.; Anderson, R.; Horowitz, S.; Christensen, C.; Judkoff, R.
2011-04-01
This report describes an analysis method for determining optimal residential energy efficiency retrofit packages and, as an illustrative example, applies the analysis method to a 1960s-era home in eight U.S. cities covering a range of International Energy Conservation Code (IECC) climate regions. The method uses an optimization scheme that considers average energy use (determined from building energy simulations) and equivalent annual cost to recommend optimal retrofit packages specific to the building, occupants, and location.
Renewable Energy Planning: Multiparametric Cost Optimization; Preprint
Walker, A.
2008-05-01
This paper describes a method for determining the combination of renewable energy technologies that minimize life-cycle cost at a facility, often with a specified goal regarding percent of energy use from renewable sources. Technologies include: photovoltaics (PV); wind; solar thermal heat and electric; solar ventilation air preheating; solar water heating; biomass heat and electric (combustion, gasification, pyrolysis, anaerobic digestion); and daylighting. The method rests upon the National Renewable Energy Laboratory's (NREL's) capabilities in characterization of technology cost and performance, geographic information systems (GIS) resource assessment, and life-cycle cost analysis. The paper discusses how to account for the way candidate technologies interact with each other, and the solver routine used to determine the combination that minimizes life-cycle cost. Results include optimal sizes of each technology, initial cost, operating cost, and life-cycle cost, including incentives from utilities or governments. Results inform early planning to identify and prioritize projects at a site for subsequent engineering and economic feasibility study.
26 CFR 509.120 - Double taxation claims.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 19 2010-04-01 2010-04-01 false Double taxation claims. 509.120 Section 509.120... CONVENTIONS SWITZERLAND General Income Tax § 509.120 Double taxation claims. (a) General. Under Article XVII... United States or Switzerland has resulted, or will result, in double taxation contrary to the...
26 CFR 509.120 - Double taxation claims.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 19 2014-04-01 2010-04-01 true Double taxation claims. 509.120 Section 509.120... CONVENTIONS SWITZERLAND General Income Tax § 509.120 Double taxation claims. (a) General. Under Article XVII... United States or Switzerland has resulted, or will result, in double taxation contrary to the...
26 CFR 509.120 - Double taxation claims.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 19 2011-04-01 2010-04-01 true Double taxation claims. 509.120 Section 509.120... CONVENTIONS SWITZERLAND General Income Tax § 509.120 Double taxation claims. (a) General. Under Article XVII... United States or Switzerland has resulted, or will result, in double taxation contrary to the...
26 CFR 509.120 - Double taxation claims.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 19 2012-04-01 2010-04-01 true Double taxation claims. 509.120 Section 509.120... CONVENTIONS SWITZERLAND General Income Tax § 509.120 Double taxation claims. (a) General. Under Article XVII... United States or Switzerland has resulted, or will result, in double taxation contrary to the...
26 CFR 509.120 - Double taxation claims.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 19 2013-04-01 2010-04-01 true Double taxation claims. 509.120 Section 509.120... CONVENTIONS SWITZERLAND General Income Tax § 509.120 Double taxation claims. (a) General. Under Article XVII... United States or Switzerland has resulted, or will result, in double taxation contrary to the...
Taxation in Public Education. Analysis and Bibliography Series, No. 12.
ERIC Educational Resources Information Center
Ross, Larry L.
Intended for both researchers and practitioners, this analysis and bibliography cites approximately 100 publications on educational taxation, including general texts and reports, statistical reports, taxation guidelines, and alternative proposals for taxation. Topics covered in the analysis section include State and Federal aid, urban and suburban…
7 CFR 400.710 - Preemption and premium taxation.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 6 2010-01-01 2010-01-01 false Preemption and premium taxation. 400.710 Section 400... of Policies and Rates of Premium § 400.710 Preemption and premium taxation. A policy or plan of insurance that is approved by the Board for FCIC reinsurance is preempted from state and local taxation....
Energy-optimal path planning by stochastic dynamically orthogonal level-set optimization
NASA Astrophysics Data System (ADS)
Subramani, Deepak N.; Lermusiaux, Pierre F. J.
2016-04-01
A stochastic optimization methodology is formulated for computing energy-optimal paths from among time-optimal paths of autonomous vehicles navigating in a dynamic flow field. Based on partial differential equations, the methodology rigorously leverages the level-set equation that governs time-optimal reachability fronts for a given relative vehicle-speed function. To set up the energy optimization, the relative vehicle-speed and headings are considered to be stochastic and new stochastic Dynamically Orthogonal (DO) level-set equations are derived. Their solution provides the distribution of time-optimal reachability fronts and corresponding distribution of time-optimal paths. An optimization is then performed on the vehicle's energy-time joint distribution to select the energy-optimal paths for each arrival time, among all stochastic time-optimal paths for that arrival time. Numerical schemes to solve the reduced stochastic DO level-set equations are obtained, and accuracy and efficiency considerations are discussed. These reduced equations are first shown to be efficient at solving the governing stochastic level-sets, in part by comparisons with direct Monte Carlo simulations. To validate the methodology and illustrate its accuracy, comparisons with semi-analytical energy-optimal path solutions are then completed. In particular, we consider the energy-optimal crossing of a canonical steady front and set up its semi-analytical solution using a energy-time nested nonlinear double-optimization scheme. We then showcase the inner workings and nuances of the energy-optimal path planning, considering different mission scenarios. Finally, we study and discuss results of energy-optimal missions in a wind-driven barotropic quasi-geostrophic double-gyre ocean circulation.
Taxation of United States general aviation
NASA Astrophysics Data System (ADS)
Sobieralski, Joseph Bernard
General aviation in the United States has been an important part of the economy and American life. General aviation is defined as all flying excluding military and scheduled airline operations, and is utilized in many areas of our society. The majority of aircraft operations and airports in the United States are categorized as general aviation, and general aviation contributes more than one percent to the United States gross domestic product each year. Despite the many benefits of general aviation, the lead emissions from aviation gasoline consumption are of great concern. General aviation emits over half the lead emissions in the United States or over 630 tons in 2005. The other significant negative externality attributed to general aviation usage is aircraft accidents. General aviation accidents have caused over 8000 fatalities over the period 1994-2006. A recent Federal Aviation Administration proposed increase in the aviation gasoline tax from 19.4 to 70.1 cents per gallon has renewed interest in better understanding the implications of such a tax increase as well as the possible optimal rate of taxation. Few studies have examined aviation fuel elasticities and all have failed to study general aviation fuel elasticities. Chapter one fills that gap and examines the elasticity of aviation gasoline consumption in United States general aviation. Utilizing aggregate time series and dynamic panel data, the price and income elasticities of demand are estimated. The price elasticity of demand for aviation gasoline is estimated to range from -0.093 to -0.185 in the short-run and from -0.132 to -0.303 in the long-run. These results prove to be similar in magnitude to automobile gasoline elasticities and therefore tax policies could more closely mirror those of automobile tax policies. The second chapter examines the costs associated with general aviation accidents. Given the large number of general aviation operations as well as the large number of fatalities and
Maximizing Thermal Efficiency and Optimizing Energy Management (Fact Sheet)
Not Available
2012-03-01
Researchers at the Thermal Test Facility (TTF) on the campus of the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in Golden, Colorado, are addressing maximizing thermal efficiency and optimizing energy management through analysis of efficient heating, ventilating, and air conditioning (HVAC) strategies, automated home energy management (AHEM), and energy storage systems.
Personal Income Taxation. National Education Association Search.
ERIC Educational Resources Information Center
National Education Association, Washington, DC. Research Div.
The second in a series on school finance, this report describes the principles of fair and adequate state and local income taxation. The political setting is discussed, and the nature of indiviudal income taxes is explained by examining which states tax income and what income they tax. Tables 2, 3, and 4 demonstrate the expanding school financing…
Optimal Design of RF Energy Harvesting Device Using Genetic Algorithm
NASA Astrophysics Data System (ADS)
Mori, T.; Sato, Y.; Adriano, R.; Igarashi, H.
2015-11-01
This paper presents optimal design of an RF energy harvesting device using genetic algorithm (GA). In the present RF harvester, a planar spiral antenna (PSA) is loaded with matching and rectifying circuits. On the first stage of the optimal design, the shape parameters of PSA are optimized using . Then, the equivalent circuit of the optimized PSA is derived for optimization of the circuits. Finally, the parameters of RF energy harvesting circuit are optimized to maximize the output power using GA. It is shown that the present optimization increases the output power by a factor of five. The manufactured energy harvester starts working when the input electric field is greater than 0.5 V/m.
Continuously Optimized Reliable Energy (CORE) Microgrid: Models & Tools (Fact Sheet)
Not Available
2013-07-01
This brochure describes Continuously Optimized Reliable Energy (CORE), a trademarked process NREL employs to produce conceptual microgrid designs. This systems-based process enables designs to be optimized for economic value, energy surety, and sustainability. Capabilities NREL offers in support of microgrid design are explained.
Method for Determining Optimal Residential Energy Efficiency Retrofit Packages
Polly, B.; Gestwick, M.; Bianchi, M.; Anderson, R.; Horowitz, S.; Christensen, C.; Judkoff, R.
2011-04-01
Businesses, government agencies, consumers, policy makers, and utilities currently have limited access to occupant-, building-, and location-specific recommendations for optimal energy retrofit packages, as defined by estimated costs and energy savings. This report describes an analysis method for determining optimal residential energy efficiency retrofit packages and, as an illustrative example, applies the analysis method to a 1960s-era home in eight U.S. cities covering a range of International Energy Conservation Code (IECC) climate regions. The method uses an optimization scheme that considers average energy use (determined from building energy simulations) and equivalent annual cost to recommend optimal retrofit packages specific to the building, occupants, and location. Energy savings and incremental costs are calculated relative to a minimum upgrade reference scenario, which accounts for efficiency upgrades that would occur in the absence of a retrofit because of equipment wear-out and replacement with current minimum standards.
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.
Program optimizations: The interplay between power, performance, and energy
Leon, Edgar A.; Karlin, Ian; Grant, Ryan E.; Dosanjh, Matthew
2016-05-16
Practical considerations for future supercomputer designs will impose limits on both instantaneous power consumption and total energy consumption. Working within these constraints while providing the maximum possible performance, application developers will need to optimize their code for speed alongside power and energy concerns. This paper analyzes the effectiveness of several code optimizations including loop fusion, data structure transformations, and global allocations. A per component measurement and analysis of different architectures is performed, enabling the examination of code optimizations on different compute subsystems. Using an explicit hydrodynamics proxy application from the U.S. Department of Energy, LULESH, we show how code optimizationsmore » impact different computational phases of the simulation. This provides insight for simulation developers into the best optimizations to use during particular simulation compute phases when optimizing code for future supercomputing platforms. Here, we examine and contrast both x86 and Blue Gene architectures with respect to these optimizations.« less
A trade based view on casino taxation: market conditions.
Li, Guoqiang; Gu, Xinhua; Wu, Jie
2015-06-01
This article presents a trade based theory of casino taxation along with empirical evidence found from Macao as a typical tourism resort. We prove that there is a unique optimum gaming tax in a particular market for casino gambling, argue that any change in this tax is engendered by external demand shifts, and suggest that the economic rent from gambling legalization should be shared through such optimal tax between the public and private sectors. Our work also studies the tradeoff between economic benefits and social costs arising from casino tourism, and provides some policy recommendations for the sustainable development of gaming-led economies. The theoretical arguments in this article turn out to be consistent with empirical observations on Macao realities over the recent decade. PMID:23979590
Automated Multivariate Optimization Tool for Energy Analysis: Preprint
Ellis, P. G.; Griffith, B. T.; Long, N.; Torcellini, P. A.; Crawley, D.
2006-07-01
Building energy simulations are often used for trial-and-error evaluation of ''what-if'' options in building design--a limited search for an optimal solution, or ''optimization''. Computerized searching has the potential to automate the input and output, evaluate many options, and perform enough simulations to account for the complex interactions among combinations of options. This paper describes ongoing efforts to develop such a tool. The optimization tool employs multiple modules, including a graphical user interface, a database, a preprocessor, the EnergyPlus simulation engine, an optimization engine, and a simulation run manager. Each module is described and the overall application architecture is summarized.
A Behavioral Economics Perspective on Tobacco Taxation
2010-01-01
Economic studies of taxation typically estimate external costs of tobacco use to be low and refrain from recommending large tobacco taxes. Behavioral economics suggests that a rational decision-making process by individuals fully aware of tobacco's hazards might still lead to overconsumption through the psychological tendency to favor immediate gratification over future harm. Taxes can serve as a self-control device to help reduce tobacco use and enable successful quit attempts. Whether taxes are appropriately high depends on how excessively people underrate the harm from tobacco use and varies with a country's circumstances. Such taxes are likely to be more equitable for poorer subgroups than traditional economic analysis suggests, which would strengthen the case for increased tobacco taxation globally. PMID:20220113
Optimization of directional elastic energy propagation
NASA Astrophysics Data System (ADS)
Andreassen, Erik; Chang, Hannah R.; Ruzzene, Massimo; Jensen, Jakob Søndergaard
2016-09-01
The aim of this paper is to demonstrate how topology optimization can be used to design a periodically perforated plate, in order to obtain a tailored anisotropic group velocity profile. The main method is demonstrated on both low and high frequency bending wave propagation in an aluminum plate, but is general in the sense that it could be used to design periodic structures with frequency dependent group velocity profiles for any kind of elastic wave propagation. With the proposed method the resulting design is manufacturable. Measurements on an optimized design compare excellently with the numerical results.
Pattern of state coal taxation. [Review
Gulley, D.A.
1981-01-01
This paper reviews the recent history of state coal taxation and reports an empirically-based effort at defining the key determinants of state and local coal taxation. A pattern emerges but the analysis is complicated by the empirical and conceptual difficulties typical of such studies. Perhaps as important a result as the detection of a pattern is the recognition that many seemingly important variables do not appear to have consistently influenced tax levels. For policy makers and for industry, it appears that the present concern over a coal-states cartel is excessive. One can speculate that draconian tax adjustments on the basis of a crude-indicator-like reserve base will ultimately transfer less wealth than would skillful preemption of rent. It is also noteworthy that the sign of the tax effort variable is positive, indicating that coal tax rates are consistent with other tax efforts, not a substitute for them. Accepting impacts and general tax effort variables as the best explanations of interstate variations in tax effort is a somewhat different matter than determining what any given state's tax rate ought to be; such a question lies beyond the scope of this paper. This tax-determinant study can not define the right level of coal taxation, but it can suggest that no trend is yet evident toward entrepreneurial tax rates. 20 references, 4 figures.
Optimal ''image-based'' weighting for energy-resolved CT
Schmidt, Taly Gilat
2009-07-15
This paper investigates a method of reconstructing images from energy-resolved CT data with negligible beam-hardening artifacts and improved contrast-to-nosie ratio (CNR) compared to conventional energy-weighting methods. Conceptually, the investigated method first reconstructs separate images from each energy bin. The final image is a linear combination of the energy-bin images, with the weights chosen to maximize the CNR in the final image. The optimal weight of a particular energy-bin image is derived to be proportional to the contrast-to-noise-variance ratio in that image. The investigated weighting method is referred to as ''image-based'' weighting, although, as will be described, the weights can be calculated and the energy-bin data combined prior to reconstruction. The performance of optimal image-based energy weighting with respect to CNR and beam-hardening artifacts was investigated through simulations and compared to that of energy integrating, photon counting, and previously studied optimal ''projection-based'' energy weighting. Two acquisitions were simulated: dedicated breast CT and a conventional thorax scan. The energy-resolving detector was simulated with five energy bins. Four methods of estimating the optimal weights were investigated, including task-specific and task-independent methods and methods that require a single reconstruction versus multiple reconstructions. Results demonstrated that optimal image-based weighting improved the CNR compared to energy-integrating weighting by factors of 1.15-1.6 depending on the task. Compared to photon-counting weighting, the CNR improvement ranged from 1.0 to 1.3. The CNR improvement factors were comparable to those of projection-based optimal energy weighting. The beam-hardening cupping artifact increased from 5.2% for energy-integrating weighting to 12.8% for optimal projection-based weighting, while optimal image-based weighting reduced the cupping to 0.6%. Overall, optimal image-based energy weighting
REopt: A Platform for Energy System Integration and Optimization: Preprint
Simpkins, T.; Cutler, D.; Anderson, K.; Olis, D.; Elgqvist, E.; Callahan, M.; Walker, A.
2014-08-01
REopt is NREL's energy planning platform offering concurrent, multi-technology integration and optimization capabilities to help clients meet their cost savings and energy performance goals. The REopt platform provides techno-economic decision-support analysis throughout the energy planning process, from agency-level screening and macro planning to project development to energy asset operation. REopt employs an integrated approach to optimizing a site?s energy costs by considering electricity and thermal consumption, resource availability, complex tariff structures including time-of-use, demand and sell-back rates, incentives, net-metering, and interconnection limits. Formulated as a mixed integer linear program, REopt recommends an optimally-sized mix of conventional and renewable energy, and energy storage technologies; estimates the net present value associated with implementing those technologies; and provides the cost-optimal dispatch strategy for operating them at maximum economic efficiency. The REopt platform can be customized to address a variety of energy optimization scenarios including policy, microgrid, and operational energy applications. This paper presents the REopt techno-economic model along with two examples of recently completed analysis projects.
Energy-Constrained Optimal Quantization for Wireless Sensor Networks
NASA Astrophysics Data System (ADS)
Luo, Xiliang; Giannakis, Georgios B.
2007-12-01
As low power, low cost, and longevity of transceivers are major requirements in wireless sensor networks, optimizing their design under energy constraints is of paramount importance. To this end, we develop quantizers under strict energy constraints to effect optimal reconstruction at the fusion center. Propagation, modulation, as well as transmitter and receiver structures are jointly accounted for using a binary symmetric channel model. We first optimize quantization for reconstructing a single sensor's measurement, and deriving the optimal number of quantization levels as well as the optimal energy allocation across bits. The constraints take into account not only the transmission energy but also the energy consumed by the transceiver's circuitry. Furthermore, we consider multiple sensors collaborating to estimate a deterministic parameter in noise. Similarly, optimum energy allocation and optimum number of quantization bits are derived and tested with simulated examples. Finally, we study the effect of channel coding on the reconstruction performance under strict energy constraints and jointly optimize the number of quantization levels as well as the number of channel uses.
Fully localised nonlinear energy growth optimals in pipe flow
NASA Astrophysics Data System (ADS)
Pringle, Chris C. T.; Willis, Ashley P.; Kerswell, Rich R.
2015-06-01
A new, fully localised, energy growth optimal is found over large times and in long pipe domains at a given mass flow rate. This optimal emerges at a threshold disturbance energy below which a nonlinear version of the known (streamwise-independent) linear optimal [P. J. Schmid and D. S. Henningson, "Optimal energy density growth in Hagen-Poiseuille flow," J. Fluid Mech. 277, 192-225 (1994)] is selected and appears to remain the optimal up until the critical energy at which transition is triggered. The form of this optimal is similar to that found in short pipes [Pringle et al., "Minimal seeds for shear flow turbulence: Using nonlinear transient growth to touch the edge of chaos," J. Fluid Mech. 702, 415-443 (2012)], but now with full localisation in the streamwise direction. This fully localised optimal perturbation represents the best approximation yet of the minimal seed (the smallest perturbation which is arbitrarily close to states capable of triggering a turbulent episode) for "real" (laboratory) pipe flows. Dependence of the optimal with respect to several parameters has been computed and establishes that the structure is robust.
Fully localised nonlinear energy growth optimals in pipe flow
Pringle, Chris C. T.; Willis, Ashley P.; Kerswell, Rich R.
2015-06-15
A new, fully localised, energy growth optimal is found over large times and in long pipe domains at a given mass flow rate. This optimal emerges at a threshold disturbance energy below which a nonlinear version of the known (streamwise-independent) linear optimal [P. J. Schmid and D. S. Henningson, “Optimal energy density growth in Hagen-Poiseuille flow,” J. Fluid Mech. 277, 192–225 (1994)] is selected and appears to remain the optimal up until the critical energy at which transition is triggered. The form of this optimal is similar to that found in short pipes [Pringle et al., “Minimal seeds for shear flow turbulence: Using nonlinear transient growth to touch the edge of chaos,” J. Fluid Mech. 702, 415–443 (2012)], but now with full localisation in the streamwise direction. This fully localised optimal perturbation represents the best approximation yet of the minimal seed (the smallest perturbation which is arbitrarily close to states capable of triggering a turbulent episode) for “real” (laboratory) pipe flows. Dependence of the optimal with respect to several parameters has been computed and establishes that the structure is robust.
Minimum energy paths for optimal oscillatory movements of PUMA arm
Olgac, N.; Zhou, S.
1988-08-01
This paper employs a geometric approach in reducing the number of time-consuming iterations necessary for the numerical solution of an optimal energy consumption problem for small amplitude oscillatory motions of robot manipulators. A general objective function in joint space is given for the energy needs in the drives, and specific applications for a commercially available manipulator, Unimation-PUMA 560, are carried out by separating the manipulator motions into two parallel segments: arm and wrist. This process, in general, leads to a highly nonlinear and transcendental optimization problem. The geometric study is presented, and the shortened numerical optimization is carried out. For any given point in the workspace, optimal directions of oscillations and their corresponding energy levels are found. This information is translated into a map of minimum energy levels across the workspace. The map will comprise a section of an intelligent control mechanism of larger scope which is conceived for ultimate use in space and subsea robotic operations. 6 references.
Depletable externalities and Pigouvian taxation
Freeman, A.M. III
1984-06-01
In their book Baumol and Oates (The Theory of Environmental Policy: Externalities, Public Outlays, and the Quality of Life; Prentice-Hall, Englewood Cliffs, NJ (1975).) argue that whether an externality is depletable (private) or undepletable (public) is the key characteristic in determining the optimal pricing pattern. They argue that unlike the undepletable case a negative depletable externality requires not only a charge or tax on the generator of the externality but a payment or compensation to the victim in order to achieve Pareto optimality. It is shown that the key characteristic determining whether compensation of victims is required for efficiency is not the depletability of the externality but whether the victim can costlessly control or limit the amount of the damaging substance received. 6 references.
Research on the optimal energy consumption of oil pipeline.
Liu, Enbin; Li, Changjun; Yang, Liuting; Liu, Song; Wu, Mingchang; Wang, Di
2015-07-01
Most of the Chinese crude oil is easy to curdle and has high viscosity, so heating transportation is usually selected. Energy consumption by this method mainly comes from furnaces and pumps. Currently, operating parameters of these pipelines were determined according to experience of dispatch. It cause high energy consumption and high cost of pipeline running, so it could not adapt to energy conservation policy. The present study focused on consuming lowest energy to operate oil transportation line. To begin with, several optimization variables were set which included pump combinations, suction pressure, discharge pressure, and station temperature. Then constraint conditions were set to establish an optimal mathematical model of running transportation line. Furthermore, genetic algorithm was used to solve the model, in meantime, selection operation, cross operation and mutation operation in the genetic algorithm were improved. Finally, a crude oil pipeline running optimization software was developed. Through optimal analyzing, S-L transportation line and contrasting with the actual working conditions, it was found that optimal operation scheme could reduce energy consumption by 5% - 9%. In addition, optimal operation scheme also considered the effect of seasons and flow on energy consumption of S-L transportation line. PMID:26387343
An Optimization Framework for Dynamic Hybrid Energy Systems
Wenbo Du; Humberto E Garcia; Christiaan J.J. Paredis
2014-03-01
A computational framework for the efficient analysis and optimization of dynamic hybrid energy systems (HES) is developed. A microgrid system with multiple inputs and multiple outputs (MIMO) is modeled using the Modelica language in the Dymola environment. The optimization loop is implemented in MATLAB, with the FMI Toolbox serving as the interface between the computational platforms. Two characteristic optimization problems are selected to demonstrate the methodology and gain insight into the system performance. The first is an unconstrained optimization problem that optimizes the dynamic properties of the battery, reactor and generator to minimize variability in the HES. The second problem takes operating and capital costs into consideration by imposing linear and nonlinear constraints on the design variables. The preliminary optimization results obtained in this study provide an essential step towards the development of a comprehensive framework for designing HES.
Optimal weight based on energy imbalance and utility maximization
NASA Astrophysics Data System (ADS)
Sun, Ruoyan
2016-01-01
This paper investigates the optimal weight for both male and female using energy imbalance and utility maximization. Based on the difference of energy intake and expenditure, we develop a state equation that reveals the weight gain from this energy gap. We construct an objective function considering food consumption, eating habits and survival rate to measure utility. Through applying mathematical tools from optimal control methods and qualitative theory of differential equations, we obtain some results. For both male and female, the optimal weight is larger than the physiologically optimal weight calculated by the Body Mass Index (BMI). We also study the corresponding trajectories to steady state weight respectively. Depending on the value of a few parameters, the steady state can either be a saddle point with a monotonic trajectory or a focus with dampened oscillations.
Dynamic optimization of district energy grid
NASA Astrophysics Data System (ADS)
Salsbery, Scott
The University of Iowa Power Plant operates utility generation and distribution for campus facilities, including electricity, steam, and chilled water. It is desirable to evaluate the optimal load combination of boilers, engines and chillers to meet the demand at minimal cost, particularly for future demand scenarios. An algorithm has been developed which takes into account the performance of individual units as part of the mix which ultimately supplies the campus and determine the degree that each should be operating to most efficiently meet demand. The algorithm is part of an integrated simulation tool which is specifically designed to apply traditional optimization techniques for a given (both current and possible) circumstance. The second component is to couple the algorithm with accurate estimates and historical data through which expected demand could be predicted. The simulation tool can account for any theoretical circumstance, which will be highly beneficial for strategic planning. As part of the process it is also necessary to determine the unique operating characteristics of the system components. The algorithms rely upon performance curves of individual system components (boiler, chiller, etc.) and those must be developed and refined when possible from experimental testing and commissioning or manufacturer supplied data.
26 CFR 1.405-3 - Taxation of retirement bonds.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Taxation of retirement bonds. 1.405-3 Section 1... (CONTINUED) INCOME TAXES Pension, Profit-Sharing, Stock Bonus Plans, Etc. § 1.405-3 Taxation of retirement..., profit-sharing, or stock bonus plan, employer contributions on behalf of his common-law employees under...
26 CFR 1.501(a)-1 - Exemption from taxation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Exemption from taxation. 1.501(a)-1 Section 1.501... (CONTINUED) INCOME TAXES (CONTINUED) Exempt Organizations § 1.501(a)-1 Exemption from taxation. (a) In... law or regulations or for other good cause, an organization that has been determined by...
7 CFR 400.710 - Preemption and premium taxation.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 6 2013-01-01 2013-01-01 false Preemption and premium taxation. 400.710 Section 400.710 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE... of Policies and Rates of Premium § 400.710 Preemption and premium taxation. A policy or plan...
7 CFR 400.710 - Preemption and premium taxation.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 6 2012-01-01 2012-01-01 false Preemption and premium taxation. 400.710 Section 400.710 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE... of Policies and Rates of Premium § 400.710 Preemption and premium taxation. A policy or plan...
7 CFR 400.710 - Preemption and premium taxation.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 6 2014-01-01 2014-01-01 false Preemption and premium taxation. 400.710 Section 400.710 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE... of Policies and Rates of Premium § 400.710 Preemption and premium taxation. A policy or plan...
7 CFR 400.710 - Preemption and premium taxation.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 6 2011-01-01 2011-01-01 false Preemption and premium taxation. 400.710 Section 400.710 Agriculture Regulations of the Department of Agriculture (Continued) FEDERAL CROP INSURANCE... of Policies and Rates of Premium § 400.710 Preemption and premium taxation. A policy or plan...
Urban Property Taxation: I. Administrative Aspects. Exchange Bibliography 479.
ERIC Educational Resources Information Center
White, Anthony G.
This is one of three related bibliographies listing publications dealing with the broad topic of property taxation. This particular volume deals with general purpose material (criticisms, suggestions, general theory and administration), as well as assessment practices, policy, evaluations of real and personal property taxation systems, and local…
Urban Property Taxation: II. Land and Location. Exchange Bibliography 480.
ERIC Educational Resources Information Center
White, Anthony G.
This is one of three related bibliographies listing publications dealing with the broad topic of property taxation. This particular volume concerns some specialized fields of study, including locational theory, land use and taxation, property markets and valuation, housing, and urban renewal and redevelopment. Citations are listed alphabetically…
32 CFR 643.56 - Taxation of lessee's interest.
Code of Federal Regulations, 2010 CFR
2010-07-01
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38 CFR 6.7 - Claims of creditors, taxation.
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20 CFR 243.4 - Taxation of benefits.
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2010-04-01
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26 CFR 26.2653-1 - Taxation of multiple skips.
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2010-04-01
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20 CFR 243.4 - Taxation of benefits.
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2011-04-01
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20 CFR 243.4 - Taxation of benefits.
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2013-04-01
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26 CFR 1.61-21 - Taxation of fringe benefits.
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2010-04-01
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26 CFR 1.61-21 - Taxation of fringe benefits.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 2 2011-04-01 2011-04-01 false Taxation of fringe benefits. 1.61-21 Section 1.61-21 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-21 Taxation of fringe benefits....
26 CFR 1.61-21 - Taxation of fringe benefits.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 2 2013-04-01 2013-04-01 false Taxation of fringe benefits. 1.61-21 Section 1.61-21 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-21 Taxation of fringe benefits....
26 CFR 1.61-21 - Taxation of fringe benefits.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 2 2014-04-01 2014-04-01 false Taxation of fringe benefits. 1.61-21 Section 1.61-21 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-21 Taxation of fringe benefits....
26 CFR 1.61-21 - Taxation of fringe benefits.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 2 2012-04-01 2012-04-01 false Taxation of fringe benefits. 1.61-21 Section 1.61-21 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-21 Taxation of fringe benefits....
Image processing to optimize wave energy converters
NASA Astrophysics Data System (ADS)
Bailey, Kyle Marc-Anthony
The world is turning to renewable energies as a means of ensuring the planet's future and well-being. There have been a few attempts in the past to utilize wave power as a means of generating electricity through the use of Wave Energy Converters (WEC), but only recently are they becoming a focal point in the renewable energy field. Over the past few years there has been a global drive to advance the efficiency of WEC. Placing a mechanical device either onshore or offshore that captures the energy within ocean surface waves to drive a mechanical device is how wave power is produced. This paper seeks to provide a novel and innovative way to estimate ocean wave frequency through the use of image processing. This will be achieved by applying a complex modulated lapped orthogonal transform filter bank to satellite images of ocean waves. The complex modulated lapped orthogonal transform filterbank provides an equal subband decomposition of the Nyquist bounded discrete time Fourier Transform spectrum. The maximum energy of the 2D complex modulated lapped transform subband is used to determine the horizontal and vertical frequency, which subsequently can be used to determine the wave frequency in the direction of the WEC by a simple trigonometric scaling. The robustness of the proposed method is provided by the applications to simulated and real satellite images where the frequency is known.
Optimizing Ice Thermal Storage to Reduce Energy Cost
NASA Astrophysics Data System (ADS)
Hall, Christopher L.
Energy cost for buildings is an issue of concern for owners across the U.S. The bigger the building, the greater the concern. A part of this is due to the energy required to cool the building and the way in which charges are set when paying for energy consumed during different times of the day. This study will prove that designing ice thermal storage properly will minimize energy cost in buildings. The effectiveness of ice thermal storage as a means to reduce energy costs lies within transferring the time of most energy consumption from on-peak to off-peak periods. Multiple variables go into the equation of finding the optimal use of ice thermal storage and they are all judged with the final objective of minimizing monthly energy costs. This research discusses the optimal design of ice thermal storage and its impact on energy consumption, energy demand, and the total energy cost. A tool for optimal design of ice thermal storage is developed, considering variables such as chiller and ice storage sizes and charging and discharge times. The simulations take place in a four-story building and investigate the potential of Ice Thermal Storage as a resource in reducing and minimizing energy cost for cooling. The simulations test the effectiveness of Ice Thermal Storage implemented into the four-story building in ten locations across the United States.
Vacuum Pump System Optimization Saves Energy at a Dairy Farm
2001-08-01
In 1998, S&S Dairy optimized the vacuum pumping system at their dairy farm in Modesto, California. In an effort to reduce energy costs, S&S Dairy evaluated their vacuum pumping system to determine if efficiency gains and energy savings were possible.
Progressive taxation and the subjective well-being of nations.
Oishi, Shigehiro; Schimmack, Ulrich; Diener, Ed
2012-01-01
Using data from the Gallup World Poll, we examined whether progressive taxation is associated with increased levels of subjective well-being. Consistent with Rawls's theory of justice, our results showed that progressive taxation was positively associated with the subjective well-being of nations. However, the overall tax rate and government spending were not associated with the subjective well-being of nations. Furthermore, controlling for the wealth of nations and income inequality, we found that respondents living in a nation with more-progressive taxation evaluated their lives as closer to the best possible life and reported having more positive and less negative daily experiences than did respondents living in a nation with less-progressive taxation. Finally, we found that the association between more-progressive taxation and higher levels of subjective well-being was mediated by citizens' satisfaction with public goods, such as education and public transportation. PMID:22157676
Optimization of energy systems under the aspect of sustainability
Ludwig, B.
1997-12-31
One of the basic ideas of technology assessment (TA) is to point out alternatives to any approached problem solution. This includes, for instance, with respect to the aim of sustainable development, the requirement of better solutions for technical applications. This idea of TA can be taken as an optimization problem. Optimization of a technical application is aimed to its energy efficiency, its material intensity, or its sustainability, respectively. The application of usual optimization procedures is limited especially in the case of a multicriterial evaluation. Restraints could be nonlinear problems, or problems with many parameters, or many restrictions due to the programming effort and memory demand of the computer. Natural optimization techniques, named as selective, genetic, or evolutionary techniques, orient on principles of evolutionary biology. These techniques do not have requirements to linearity, differentiation or a certain problem structure and have often a less programming effort, for they are predestined to apply to TA. In this contribution a new optimization technique based on a combination of soft computing methods is presented and applied to energy conversion technologies. The technology mix building an energy supply system is evaluated with a fuzzy logic based approach and optimized with a genetic algorithm. The results are properties and compounds required to future energy conversion technologies under the aspects of a sustainable development.
Efficiency Mode of Energy Management based on Optimal Flight Path
NASA Astrophysics Data System (ADS)
Yang, Ling-xiao
2016-07-01
One new method of searching the optimal flight path in target function is put forward, which is applied to energy section for reentry flight vehicle, and the optimal flight path in which the energy is managed to decline rapidly, is settled by this design. The research for energy management is meaningful for engineering, it can also improve the applicability and flexibility for vehicle. The angle-of-attack and the bank angle are used to regulate energy and range at unpowered reentry flight as control variables. Firstly, the angle-of-attack section for minimum lift-to-drag ratio is ensured by the relation of range and lift-to-drag ratio. Secondly, build the secure boundary for flight corridor by restrictions in flight. Thirdly, the D-e section is optimized for energy expending in corridor by the influencing rule of the D-e section and range. Finally, compare this design method with the traditional Pseudo-spectral method. Moreover, energy-managing is achieved by cooperating lateral motion, and the optimized D-e section is tracked to prove the practicability of programming flight path with energy management.
Optimization of Transient Heat Exchanger Performance for Improved Energy Efficiency
NASA Astrophysics Data System (ADS)
Bran Anleu, Gabriela; Kavehpour, Pirouz; Lavine, Adrienne; Wirz, Richard
2014-11-01
Heat exchangers are used in a multitude of applications within systems for energy generation, energy conversion, or energy storage. Many of these systems (e.g. solar power plants) function under transient conditions, but the design of the heat exchangers is typically optimized assuming steady state conditions. There is a potential for significant energy savings if the transient behavior of the heat exchanger is taken into account in designing the heat exchanger by optimizing its operating conditions in relation to the transient behavior of the overall system. The physics of the transient behavior of a heat exchanger needs to be understood to provide design parameters for transient heat exchangers to deliver energy savings. A numerical model was used to determine the optimized mass flow rates thermal properties for a thermal energy storage system. The transient behavior is strongly linked to the dimensionless parameters relating fluid properties, the mass flow rates, and the temperature of the fluids at the inlet of each stream. Smart metals, or advanced heat exchanger surface geometries and methods of construction will be used to meet the three goals mentioned before: 1) energy and cost reduction, 2) size reduction, and 3) optimal performance for all modes of operation.
Optimizing Data Centre Energy and Environmental Costs
NASA Astrophysics Data System (ADS)
Aikema, David Hendrik
Data centres use an estimated 2% of US electrical power which accounts for much of their total cost of ownership. This consumption continues to grow, further straining power grids attempting to integrate more renewable energy. This dissertation focuses on assessing and reducing data centre environmental and financial costs. Emissions of projects undertaken to lower the data centre environmental footprints can be assessed and the emission reduction projects compared using an ISO-14064-2-compliant greenhouse gas reduction protocol outlined herein. I was closely involved with the development of the protocol. Full lifecycle analysis and verifying that projects exceed business-as-usual expectations are addressed, and a test project is described. Consuming power when it is low cost or when renewable energy is available can be used to reduce the financial and environmental costs of computing. Adaptation based on the power price showed 10--50% potential savings in typical cases, and local renewable energy use could be increased by 10--80%. Allowing a fraction of high-priority tasks to proceed unimpeded still allows significant savings. Power grid operators use mechanisms called ancillary services to address variation and system failures, paying organizations to alter power consumption on request. By bidding to offer these services, data centres may be able to lower their energy costs while reducing their environmental impact. If providing contingency reserves which require only infrequent action, savings of up to 12% were seen in simulations. Greater power cost savings are possible for those ceding more control to the power grid operator. Coordinating multiple data centres adds overhead, and altering at which data centre requests are processed based on changes in the financial or environmental costs of power is likely to increase this overhead. Tests of virtual machine migrations showed that in some cases there was no visible increase in power use while in others power use
Optimal satisfaction degree in energy harvesting cognitive radio networks
NASA Astrophysics Data System (ADS)
Li, Zan; Liu, Bo-Yang; Si, Jiang-Bo; Zhou, Fu-Hui
2015-12-01
A cognitive radio (CR) network with energy harvesting (EH) is considered to improve both spectrum efficiency and energy efficiency. A hidden Markov model (HMM) is used to characterize the imperfect spectrum sensing process. In order to maximize the whole satisfaction degree (WSD) of the cognitive radio network, a tradeoff between the average throughput of the secondary user (SU) and the interference to the primary user (PU) is analyzed. We formulate the satisfaction degree optimization problem as a mixed integer nonlinear programming (MINLP) problem. The satisfaction degree optimization problem is solved by using differential evolution (DE) algorithm. The proposed optimization problem allows the network to adaptively achieve the optimal solution based on its required quality of service (Qos). Numerical results are given to verify our analysis. Project supported by the National Natural Science Foundation of China (Grant No. 61301179), the Doctorial Programs Foundation of the Ministry of Education of China (Grant No. 20110203110011), and the 111 Project (Grant No. B08038).
Multi-objective optimal dispatch of distributed energy resources
NASA Astrophysics Data System (ADS)
Longe, Ayomide
This thesis is composed of two papers which investigate the optimal dispatch for distributed energy resources. In the first paper, an economic dispatch problem for a community microgrid is studied. In this microgrid, each agent pursues an economic dispatch for its personal resources. In addition, each agent is capable of trading electricity with other agents through a local energy market. In this paper, a simple market structure is introduced as a framework for energy trades in a small community microgrid such as the Solar Village. It was found that both sellers and buyers benefited by participating in this market. In the second paper, Semidefinite Programming (SDP) for convex relaxation of power flow equations is used for optimal active and reactive dispatch for Distributed Energy Resources (DER). Various objective functions including voltage regulation, reduced transmission line power losses, and minimized reactive power charges for a microgrid are introduced. Combinations of these goals are attained by solving a multiobjective optimization for the proposed ORPD problem. Also, both centralized and distributed versions of this optimal dispatch are investigated. It was found that SDP made the optimal dispatch faster and distributed solution allowed for scalability.
Optimizing Energy Conversion: Magnetic Nano-materials
NASA Astrophysics Data System (ADS)
McIntyre, Dylan; Dann, Martin; Ilie, Carolina C.
2015-03-01
We present herein the work started at SUNY Oswego as a part of a SUNY 4E grant. The SUNY 4E Network of Excellence has awarded SUNY Oswego and collaborators a grant to carry out extensive studies on magnetic nanoparticles. The focus of the study is to develop cost effective rare-earth-free magnetic materials that will enhance energy transmission performance of various electrical devices (solar cells, electric cars, hard drives, etc.). The SUNY Oswego team has started the preliminary work for the project and graduate students from the rest of the SUNY 4E team (UB, Alfred College, Albany) will continue the project. The preliminary work concentrates on analyzing the properties of magnetic nanoparticle candidates, calculating molecular orbitals and band gap, and the fabrication of thin films. SUNY 4E Network of Excellence Grant.
Optimal Energy Consumption Analysis of Natural Gas Pipeline
Liu, Enbin; Li, Changjun; Yang, Yi
2014-01-01
There are many compressor stations along long-distance natural gas pipelines. Natural gas can be transported using different boot programs and import pressures, combined with temperature control parameters. Moreover, different transport methods have correspondingly different energy consumptions. At present, the operating parameters of many pipelines are determined empirically by dispatchers, resulting in high energy consumption. This practice does not abide by energy reduction policies. Therefore, based on a full understanding of the actual needs of pipeline companies, we introduce production unit consumption indicators to establish an objective function for achieving the goal of lowering energy consumption. By using a dynamic programming method for solving the model and preparing calculation software, we can ensure that the solution process is quick and efficient. Using established optimization methods, we analyzed the energy savings for the XQ gas pipeline. By optimizing the boot program, the import station pressure, and the temperature parameters, we achieved the optimal energy consumption. By comparison with the measured energy consumption, the pipeline now has the potential to reduce energy consumption by 11 to 16 percent. PMID:24955410
Beam-energy-spread minimization using cell-timing optimization
NASA Astrophysics Data System (ADS)
Rose, C. R.; Ekdahl, C.; Schulze, M.
2012-04-01
Beam energy spread, and related beam motion, increase the difficulty in tuning for multipulse radiographic experiments at the dual-axis radiographic hydrodynamic test facility’s axis-II linear induction accelerator (LIA). In this article, we describe an optimization method to reduce the energy spread by adjusting the timing of the cell voltages (both unloaded and loaded), either advancing or retarding, such that the injector voltage and summed cell voltages in the LIA result in a flatter energy profile. We developed a nonlinear optimization routine which accepts as inputs the 74 cell-voltage, injector voltage, and beam current waveforms. It optimizes cell timing per user-selected groups of cells and outputs timing adjustments, one for each of the selected groups. To verify the theory, we acquired and present data for both unloaded and loaded cell-timing optimizations. For the unloaded cells, the preoptimization baseline energy spread was reduced by 34% and 31% for two shots as compared to baseline. For the loaded-cell case, the measured energy spread was reduced by 49% compared to baseline.
Vibroacoustic optimization using a statistical energy analysis model
NASA Astrophysics Data System (ADS)
Culla, Antonio; D`Ambrogio, Walter; Fregolent, Annalisa; Milana, Silvia
2016-08-01
In this paper, an optimization technique for medium-high frequency dynamic problems based on Statistical Energy Analysis (SEA) method is presented. Using a SEA model, the subsystem energies are controlled by internal loss factors (ILF) and coupling loss factors (CLF), which in turn depend on the physical parameters of the subsystems. A preliminary sensitivity analysis of subsystem energy to CLF's is performed to select CLF's that are most effective on subsystem energies. Since the injected power depends not only on the external loads but on the physical parameters of the subsystems as well, it must be taken into account under certain conditions. This is accomplished in the optimization procedure, where approximate relationships between CLF's, injected power and physical parameters are derived. The approach is applied on a typical aeronautical structure: the cabin of a helicopter.
Optimal smoothing of site-energy distributions from adsorption isotherms
Brown, L.F.; Travis, B.J.
1983-01-01
The equation for the adsorption isotherm on a heterogeneous surface is a Fredholm integral equation. In solving it for the site-energy distribution (SED), some sort of smoothing must be carried out. The optimal amount of smoothing will give the most information that is possible without introducing nonexistent structure into the SED. Recently, Butler, Reeds, and Dawson proposed a criterion (the BRD criterion) for choosing the optimal smoothing parameter when using regularization to solve Fredholm equations. The BRD criterion is tested for its suitability in obtaining optimal SED's. This criterion is found to be too conservative. While using it never introduces nonexistent structure into the SED, significant information is often lost. At present, no simple criterion for choosing the optimal smoothing parameter exists, and a modeling approach is recommended.
Stochastic Optimal Scheduling of Residential Appliances with Renewable Energy Sources
Wu, Hongyu; Pratt, Annabelle; Chakraborty, Sudipta
2015-07-03
This paper proposes a stochastic, multi-objective optimization model within a Model Predictive Control (MPC) framework, to determine the optimal operational schedules of residential appliances operating in the presence of renewable energy source (RES). The objective function minimizes the weighted sum of discomfort, energy cost, total and peak electricity consumption, and carbon footprint. A heuristic method is developed for combining different objective components. The proposed stochastic model utilizes Monte Carlo simulation (MCS) for representing uncertainties in electricity price, outdoor temperature, RES generation, water usage, and non-controllable loads. The proposed model is solved using a mixed integer linear programming (MILP) solver and numerical results show the validity of the model. Case studies show the benefit of using the proposed optimization model.
Stabilized quasi-Newton optimization of noisy potential energy surfaces
NASA Astrophysics Data System (ADS)
Schaefer, Bastian; Ghasemi, S. Alireza; Roy, Shantanu; Goedecker, Stefan; Goedecker Group Team
Optimizations of atomic positions belong to the most frequently performed tasks in electronic structure calculations. Many simulations like global minimum searches or the identification of chemical reaction pathways can require the computation of hundreds or thousands of minimizations or saddle points. To automatize these tasks, optimization algorithms must not only be efficient but also very reliable. Unfortunately, computational noise in forces and energies is inherent to electronic structure codes. This computational noise poses a severe problem to the stability of efficient optimization methods like the limited-memory Broyden-Fletcher-Goldfarb-Shanno algorithm. In this talk a recently published technique that allows to obtain significant curvature information of noisy potential energy surfaces is presented. This technique was used to construct both, a stabilized quasi-Newton minimization method and a stabilized quasi-Newton saddle finding approach. With the help of benchmarks both the minimizer and the saddle finding approach were demonstrated to be superior to comparable existing methods.
OPTIMIZATION BIAS IN ENERGY-BASED STRUCTURE PREDICTION
Petrella, Robert J.
2014-01-01
Physics-based computational approaches to predicting the structure of macromolecules such as proteins are gaining increased use, but there are remaining challenges. In the current work, it is demonstrated that in energy-based prediction methods, the degree of optimization of the sampled structures can influence the prediction results. In particular, discrepancies in the degree of local sampling can bias the predictions in favor of the oversampled structures by shifting the local probability distributions of the minimum sampled energies. In simple systems, it is shown that the magnitude of the errors can be calculated from the energy surface, and for certain model systems, derived analytically. Further, it is shown that for energy wells whose forms differ only by a randomly assigned energy shift, the optimal accuracy of prediction is achieved when the sampling around each structure is equal. Energy correction terms can be used in cases of unequal sampling to reproduce the total probabilities that would occur under equal sampling, but optimal corrections only partially restore the prediction accuracy lost to unequal sampling. For multiwell systems, the determination of the correction terms is a multibody problem; it is shown that the involved cross-correlation multiple integrals can be reduced to simpler integrals. The possible implications of the current analysis for macromolecular structure prediction are discussed. PMID:25552783
IMPROVING AC MOTOR EFFICIENCY WITH FUZZY LOGIC ENERGY OPTIMIZER
The paper discusses EPA's research program to develop fuzzy-logic-based energy optimizers for alternating-current (AC) induction motors driven by Adjustable Speed Drives (ASDs). he technical goals of the program are to increase the efficiency of ASD/motor combinations (especially...
Smart Water: Energy-Water Optimization in Drinking Water Systems
This project aims to develop and commercialize a Smart Water Platform – Sensor-based Data-driven Energy-Water Optimization technology in drinking water systems. The key technological advances rely on cross-platform data acquisition and management system, model-based real-time sys...
Optimizing potential energy functions for maximal intrinsic hyperpolarizability
Zhou Juefei; Szafruga, Urszula B.; Kuzyk, Mark G.; Watkins, David S.
2007-11-15
We use numerical optimization to study the properties of (1) the class of one-dimensional potential energy functions and (2) systems of point nuclei in two dimensions that yield the largest intrinsic hyperpolarizabilities, which we find to be within 30% of the fundamental limit. In all cases, we use a one-electron model. It is found that a broad range of optimized potentials, each of very different character, yield the same intrinsic hyperpolarizability ceiling of 0.709. Furthermore, all optimized potential energy functions share common features such as (1) the value of the normalized transition dipole moment to the dominant state, which forces the hyperpolarizability to be dominated by only two excited states and (2) the energy ratio between the two dominant states. All optimized potentials are found to obey the three-level ansatz to within about 1%. Many of these potential energy functions may be implementable in multiple quantum well structures. The subset of potentials with undulations reaffirm that modulation of conjugation may be an approach for making better organic molecules, though there appear to be many others. Additionally, our results suggest that one-dimensional molecules may have larger diagonal intrinsic hyperpolarizability {beta}{sub xxx}{sup int} than higher-dimensional systems.
Analysis of EnergyPlus for use in residential building energy optimization
NASA Astrophysics Data System (ADS)
Spencer, Justin S.
This work explored the utility of EnergyPlus as a simulation engine for doing residential building energy optimization, with the objective of finding the modeling areas that require further development in EnergyPlus for residential optimization applications. This work was conducted primarily during 2006-2007, with publication occurring later in 2010. The assessments and recommendations apply to the simulation tool versions available in 2007. During this work, an EnergyPlus v2.0 (2007) input file generator was developed for use in BEopt 0.8.0.4 (2007). BEopt 0.8.0.4 is a residential Building Energy optimization program developed at the National Renewable Energy Laboratory in Golden, Colorado. Residential modeling capabilities of EnergyPlus v2.0 were scrutinized and tested. Modeling deficiencies were identified in a number of areas. These deficiencies were compared to deficiencies in the DOE2.2 V44E4(2007)/TRNSYS simulation engines. The highest priority gaps in EnergyPlus v2.0's residential modeling capability are in infiltration, duct leakage, and foundation modeling. Optimization results from DOE2.2 V44E4 and EnergyPlus v2.0 were analyzed to search for modeling differences that have a significant impact on optimization results. Optimal buildings at different energy savings levels were compared to look for biases. It was discovered that the EnergyPlus v2.0 optimizations consistently chose higher wall insulation levels than the DOE2.2 V44E4 optimizations. The points composing the optimal paths chosen by DOE2.2 V44E4 and EnergyPlus v2.0 were compared to look for points chosen by one optimization that were significantly different from the other optimal path. These outliers were compared to consensus optimal points to determine the simulation differences that cause disparities in the optimization results. The differences were primarily caused by modeling of window radiation exchange and HVAC autosizing.
Optimal Operation of Energy Storage in Power Transmission and Distribution
NASA Astrophysics Data System (ADS)
Akhavan Hejazi, Seyed Hossein
In this thesis, we investigate optimal operation of energy storage units in power transmission and distribution grids. At transmission level, we investigate the problem where an investor-owned independently-operated energy storage system seeks to offer energy and ancillary services in the day-ahead and real-time markets. We specifically consider the case where a significant portion of the power generated in the grid is from renewable energy resources and there exists significant uncertainty in system operation. In this regard, we formulate a stochastic programming framework to choose optimal energy and reserve bids for the storage units that takes into account the fluctuating nature of the market prices due to the randomness in the renewable power generation availability. At distribution level, we develop a comprehensive data set to model various stochastic factors on power distribution networks, with focus on networks that have high penetration of electric vehicle charging load and distributed renewable generation. Furthermore, we develop a data-driven stochastic model for energy storage operation at distribution level, where the distribution of nodal voltage and line power flow are modelled as stochastic functions of the energy storage unit's charge and discharge schedules. In particular, we develop new closed-form stochastic models for such key operational parameters in the system. Our approach is analytical and allows formulating tractable optimization problems. Yet, it does not involve any restricting assumption on the distribution of random parameters, hence, it results in accurate modeling of uncertainties. By considering the specific characteristics of random variables, such as their statistical dependencies and often irregularly-shaped probability distributions, we propose a non-parametric chance-constrained optimization approach to operate and plan energy storage units in power distribution girds. In the proposed stochastic optimization, we consider
Multiobjective Optimization of Low-Energy Trajectories Using Optimal Control on Dynamical Channels
NASA Technical Reports Server (NTRS)
Coffee, Thomas M.; Anderson, Rodney L.; Lo, Martin W.
2011-01-01
We introduce a computational method to design efficient low-energy trajectories by extracting initial solutions from dynamical channels formed by invariant manifolds, and improving these solutions through variational optimal control. We consider trajectories connecting two unstable periodic orbits in the circular restricted 3-body problem (CR3BP). Our method leverages dynamical channels to generate a range of solutions, and approximates the areto front for impulse and time of flight through a multiobjective optimization of these solutions based on primer vector theory. We demonstrate the application of our method to a libration orbit transfer in the Earth-Moon system.
Optimal Energy Transfer in Light-Harvesting Systems.
Chen, Lipeng; Shenai, Prathamesh; Zheng, Fulu; Somoza, Alejandro; Zhao, Yang
2015-01-01
Photosynthesis is one of the most essential biological processes in which specialized pigment-protein complexes absorb solar photons, and with a remarkably high efficiency, guide the photo-induced excitation energy toward the reaction center to subsequently trigger its conversion to chemical energy. In this work, we review the principles of optimal energy transfer in various natural and artificial light harvesting systems. We begin by presenting the guiding principles for optimizing the energy transfer efficiency in systems connected to dissipative environments, with particular attention paid to the potential role of quantum coherence in light harvesting systems. We will comment briefly on photo-protective mechanisms in natural systems that ensure optimal functionality under varying ambient conditions. For completeness, we will also present an overview of the charge separation and electron transfer pathways in reaction centers. Finally, recent theoretical and experimental progress on excitation energy transfer, charge separation, and charge transport in artificial light harvesting systems is delineated, with organic solar cells taken as prime examples. PMID:26307957
Detonation Energies of Explosives by Optimized JCZ3 Procedures
NASA Astrophysics Data System (ADS)
Stiel, Leonard; Baker, Ernest
1997-07-01
Procedures for the detonation properties of explosives have been extended for the calculation of detonation energies at adiabatic expansion conditions. Advanced variable metric optimization routines developed by ARDEC are utilized to establish chemical reaction equilibrium by the minimization of the Helmholtz free energy of the system. The use of the JCZ3 equation of state with optimized Exp-6 potential parameters leads to lower errors in JWL detonation energies than the TIGER JCZ3 procedure and other methods tested for relative volumes to 7.0. For the principal isentrope with C-J parameters and freeze conditions established at elevated pressures with the JCZ3 equation of state, best results are obtained if an alternate volumetric relationship is utilized at the highest expansions. Efficient subroutines (designated JAGUAR) have been developed which incorporate the ability to automatically generate JWL and JWLB equation of state parameters. abstract.
Spectral optimization of CPV for integrated energy output
NASA Astrophysics Data System (ADS)
McDonald, Mark; Barnes, Chris
2008-08-01
The series electrical nature of the multi-junction solar cell is both the source of its desirable overall efficiency and of its sensitivity to spectral balance. Owing to the series connection of the spectrally selective junctions, variations in the spectra of the solar input, optical transfer function, and cell quantum efficiency have significant impact on annual energy production despite being effectively indistinguishable in instantaneous power output. This paper will outline spectral filtering approaches for experimental characterization, and spectral simulation methods for estimating annual energy production. We will also present system level design to optimize for annual energy production.
Optimal residential water conservation strategies considering related energy in California
NASA Astrophysics Data System (ADS)
Escriva-Bou, Alvar; Lund, Jay R.; Pulido-Velazquez, Manuel
2015-06-01
Although most freshwater resources are used in agriculture, residential water use is a much more energy intensive user. Based on this, we analyze the increased willingness to adopt water conservation strategies if energy cost is included in the customers' utility function. Using a Water-Energy-CO2 emissions model for household water end uses and probability distribution functions for parameters affecting water and water-related energy use in 10 different locations in California, this research introduces a probabilistic two-stage optimization model considering technical and behavioral decision variables to obtain the most economical strategies to minimize household water and water-related energy bills and costs given both water and energy price shocks. Results can provide an upper bound of household savings for customers with well-behaved preferences, and show greater adoption rates to reduce energy intensive appliances when energy is accounted, resulting in an overall 24% reduction in indoor water use that represents a 30% reduction in water-related energy use and a 53% reduction in household water-related CO2 emissions. Previous use patterns and water and energy rate structures can affect greatly the potential benefits for customers and so their behavior. Given that water and energy are somewhat complementary goods for customers, we use results of the optimization to obtain own-price and cross-price elasticities of residential water use by simulating increases in water and energy prices. While the results are highly influenced by assumptions due to lack of empirical data, the method presented has no precedent in the literature and hopefully will stimulate the collection of additional relevant data.
Parallel Harmony Search Based Distributed Energy Resource Optimization
Ceylan, Oguzhan; Liu, Guodong; Tomsovic, Kevin
2015-01-01
This paper presents a harmony search based parallel optimization algorithm to minimize voltage deviations in three phase unbalanced electrical distribution systems and to maximize active power outputs of distributed energy resources (DR). The main contribution is to reduce the adverse impacts on voltage profile during a day as photovoltaics (PVs) output or electrical vehicles (EVs) charging changes throughout a day. The IEEE 123- bus distribution test system is modified by adding DRs and EVs under different load profiles. The simulation results show that by using parallel computing techniques, heuristic methods may be used as an alternative optimization tool in electrical power distribution systems operation.
Health Considerations in Regulation and Taxation of Electronic Cigarettes.
Mainous, Arch G; Tanner, Rebecca J; Mainous, Ryan W; Talbert, Jeffery
2015-01-01
The use of electronic cigarettes (e-cigarettes) is experiencing unprecedented growth. This can be contrasted to the use of conventional cigarettes which showed a decrease among adults with the current smoker prevalence dropping from 20.9% in 2005 to 17.8% in 2013. There is some data that e-cigarettes are attracting both former smokers and never smokers, and in particular, young people as users. Currently most states do not tax e-cigarettes. Taxation and regulation may have a similar overall goal of decreasing smoking but regulation tends to focus reduced availability of products. In terms of tobacco control, taxation focuses on the demand side of the equation. Taxation is a distinct strategy from regulation and has been shown to decrease new adopters of conventional cigarettes. A variety of potential taxation strategies can be considered by policymakers based on different assumptions about e-cigarettes and their utility, ranging from untaxed to taxation at moderate levels compared to conventional cigarettes to taxation equal to conventional cigarettes. Until more evidence for the benefits of e-cigarettes is presented, it seems prudent to view them as a potentially harmful and addictive product that ought to be regulated and taxed in an equivalent manner to conventional cigarettes. PMID:26546657
Energy optimization for a wind DFIG with flywheel energy storage
NASA Astrophysics Data System (ADS)
Hamzaoui, Ihssen; Bouchafaa, Farid
2016-07-01
The type of distributed generation unit that is the subject of this paper relates to renewable energy sources, especially wind power. The wind generator used is based on a double fed induction Generator (DFIG). The stator of the DFIG is connected directly to the network and the rotor is connected to the network through the power converter with three levels. The objective of this work is to study the association a Flywheel Energy Storage System (FESS) in wind generator. This system is used to improve the quality of electricity provided by wind generator. It is composed of a flywheel; an induction machine (IM) and a power electronic converter. A maximum power tracking technique « Maximum Power Point Tracking » (MPPT) and a strategy for controlling the pitch angle is presented. The model of the complete system is developed in Matlab/Simulink environment / to analyze the results from simulation the integration of wind chain to networks.
Machine learning techniques for energy optimization in mobile embedded systems
NASA Astrophysics Data System (ADS)
Donohoo, Brad Kyoshi
Mobile smartphones and other portable battery operated embedded systems (PDAs, tablets) are pervasive computing devices that have emerged in recent years as essential instruments for communication, business, and social interactions. While performance, capabilities, and design are all important considerations when purchasing a mobile device, a long battery lifetime is one of the most desirable attributes. Battery technology and capacity has improved over the years, but it still cannot keep pace with the power consumption demands of today's mobile devices. This key limiter has led to a strong research emphasis on extending battery lifetime by minimizing energy consumption, primarily using software optimizations. This thesis presents two strategies that attempt to optimize mobile device energy consumption with negligible impact on user perception and quality of service (QoS). The first strategy proposes an application and user interaction aware middleware framework that takes advantage of user idle time between interaction events of the foreground application to optimize CPU and screen backlight energy consumption. The framework dynamically classifies mobile device applications based on their received interaction patterns, then invokes a number of different power management algorithms to adjust processor frequency and screen backlight levels accordingly. The second strategy proposes the usage of machine learning techniques to learn a user's mobile device usage pattern pertaining to spatiotemporal and device contexts, and then predict energy-optimal data and location interface configurations. By learning where and when a mobile device user uses certain power-hungry interfaces (3G, WiFi, and GPS), the techniques, which include variants of linear discriminant analysis, linear logistic regression, non-linear logistic regression, and k-nearest neighbor, are able to dynamically turn off unnecessary interfaces at runtime in order to save energy.
Optimal Control of Distributed Energy Resources using Model Predictive Control
Mayhorn, Ebony T.; Kalsi, Karanjit; Elizondo, Marcelo A.; Zhang, Wei; Lu, Shuai; Samaan, Nader A.; Butler-Purry, Karen
2012-07-22
In an isolated power system (rural microgrid), Distributed Energy Resources (DERs) such as renewable energy resources (wind, solar), energy storage and demand response can be used to complement fossil fueled generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation. The problem is formulated as a multi-objective optimization problem with the goals of minimizing fuel costs and changes in power output of diesel generators, minimizing costs associated with low battery life of energy storage and maintaining system frequency at the nominal operating value. Two control modes are considered for controlling the energy storage to compensate either net load variability or wind variability. Model predictive control (MPC) is used to solve the aforementioned problem and the performance is compared to an open-loop look-ahead dispatch problem. Simulation studies using high and low wind profiles, as well as, different MPC prediction horizons demonstrate the efficacy of the closed-loop MPC in compensating for uncertainties in wind and demand.
Structural Optimization of Triboelectric Nanogenerator for Harvesting Water Wave Energy.
Jiang, Tao; Zhang, Li Min; Chen, Xiangyu; Han, Chang Bao; Tang, Wei; Zhang, Chi; Xu, Liang; Wang, Zhong Lin
2015-12-22
Ocean waves are one of the most abundant energy sources on earth, but harvesting such energy is rather challenging due to various limitations of current technologies. Recently, networks formed by triboelectric nanogenerator (TENG) have been proposed as a promising technology for harvesting water wave energy. In this work, a basic unit for the TENG network was studied and optimized, which has a box structure composed of walls made of TENG composed of a wavy-structured Cu-Kapton-Cu film and two FEP thin films, with a metal ball enclosed inside. By combination of the theoretical calculations and experimental studies, the output performances of the TENG unit were investigated for various structural parameters, such as the size, mass, or number of the metal balls. From the viewpoint of theory, the output characteristics of TENG during its collision with the ball were numerically calculated by the finite element method and interpolation method, and there exists an optimum ball size or mass to reach maximized output power and electric energy. Moreover, the theoretical results were well verified by the experimental tests. The present work could provide guidance for structural optimization of wavy-structured TENGs for effectively harvesting water wave energy toward the dream of large-scale blue energy. PMID:26567754
Wood energy fuel cycle optimization in beech and spruce forests
NASA Astrophysics Data System (ADS)
Meyer, Nickolas K.; Mina, Marco
2012-03-01
A novel synergistic approach to reducing emissions from residential wood combustion (RWC) is presented. Wood energy fuel cycle optimization (FCO) aims to provide cleaner burning fuels through optimization of forestry and renewable energy management practices. In this work, beech and spruce forests of average and high quality were modelled and analysed to determine the volume of fuel wood and its associated bark fraction produced during typical forestry cycles. Two separate fuel wood bark production regimes were observed for beech trees, while only one production regime was observed for spruce. The single tree and stand models were combined with existing thinning parameters to replicate existing management practices. Utilizing estimates of initial seedling numbers and existing thinning patterns a dynamic model was formed that responded to changes in thinning practices. By varying the thinning parameters, this model enabled optimization of the forestry practices for the reduction of bark impurities in the fuel wood supply chain. Beech forestry cycles responded well to fuel cycle optimization with volume reductions of bark from fuel wood of between ˜10% and ˜20% for average and high quality forest stands. Spruce, on the other hand, was fairly insensitive to FCO with bark reductions of 0-5%. The responsiveness of beech to FCO further supports its status as the preferred RWC fuel in Switzerland. FCO could easily be extended beyond Switzerland and applied across continental Europe and North America.
Optimal control of Formula One car energy recovery systems
NASA Astrophysics Data System (ADS)
Limebeer, D. J. N.; Perantoni, G.; Rao, A. V.
2014-10-01
The utility of orthogonal collocation methods in the solution of optimal control problems relating to Formula One racing is demonstrated. These methods can be used to optimise driver controls such as the steering, braking and throttle usage, and to optimise vehicle parameters such as the aerodynamic down force and mass distributions. Of particular interest is the optimal usage of energy recovery systems (ERSs). Contemporary kinetic energy recovery systems are studied and compared with future hybrid kinetic and thermal/heat ERSs known as ERS-K and ERS-H, respectively. It is demonstrated that these systems, when properly controlled, can produce contemporary lap time using approximately two-thirds of the fuel required by earlier generation (2013 and prior) vehicles.
Integrative energy-systems design: System structure from thermodynamic optimization
NASA Astrophysics Data System (ADS)
Ordonez, Juan Carlos
This thesis deals with the application of thermodynamic optimization to find optimal structure and operation conditions of energy systems. Chapter 1 outlines the thermodynamic optimization of a combined power and refrigeration system subject to constraints. It is shown that the thermodynamic optimum is reached by distributing optimally the heat exchanger inventory. Chapter 2 considers the maximization of power extraction from a hot stream in the presence of phase change. It shows that when the receiving (cold) stream boils in a counterflow heat exchanger, the thermodynamic optimization consists of locating the optimal capacity rate of the cold stream. Chapter 3 shows that the main architectural features of a counterflow heat exchanger can be determined based on thermodynamic optimization subject to volume constraint. Chapter 4 addresses two basic issues in the thermodynamic optimization of environmental control systems (ECS) for aircraft: realistic limits for the minimal power requirement, and design features that facilitate operation at minimal power consumption. Several models of the ECS-Cabin interaction are considered and it is shown that in all the models the temperature of the air stream that the ECS delivers to the cabin can be optimized for operation at minimal power. In chapter 5 it is shown that the sizes (weights) of heat and fluid flow systems that function on board vehicles such as aircraft can be derived from the maximization of overall (system level) performance. Chapter 6 develops analytically the optimal sizes (hydraulic diameters) of parallel channels that penetrate and cool a volume with uniformly distributed internal heat generation and Chapter 7 shows analytically and numerically how an originally uniform flow structure transforms itself into a nonuniform one when the objective is to minimize global flow losses. It is shown that flow maldistribution and the abandonment of symmetry are necessary for the development of flow structures with
Pooling optimal combinations of energy thresholds in spectroscopic CT
NASA Astrophysics Data System (ADS)
Koenig, Thomas; Zuber, Marcus; Hamann, Elias; Runz, Armin; Fiederle, Michael; Baumbach, Tilo
2014-03-01
Photon counting detectors used in spectroscopic CT are often based on small pixels and therefore offer only limited space to include energy discriminators and their associated counters in each pixel cell. For this reason, it is important to make efficient use of the available energy discriminators in order to achieve an optimized material contrast at a radiation dose as low as possible. Unfortunately, the complexity of evaluating every possible combination of energy thresholds, given a fixed number of counters, rapidly increases with the resolution at which this search is performed, and makes brute-force approaches to this problem infeasible. In this work, we introduce methods from machine learning, in particular sparse regression, to perform a feature selection to determine optimal combinations of energy thresholds. We will demonstrate how methods enforcing row-sparsity on a linear regression's coefficient matrix can be applied to the multiple response problem in spectroscopic CT, i.e. the case in which a single set of energy thresholds is sought to simultaneously retrieve concentrations pertaining to a multitude of materials in an optimal way. These methods are applied to CT images experimentally obtained with a Medipix3RX detector operated in charge summing mode and with a CdTe sensor at a pixel pitch of 110μm. We show that the least absolute shrinkage and selection operator (lasso), generalized to the multiple response case, chooses four out of 20 possible threshold positions that allow discriminating PMMA, iodine and gadolinium in a contrast agent phantom at a higher accuracy than with equally spaced thresholds. Finally, we illustrate why it might be unwise to use a higher number of energy thresholds than absolutely necessary.
Optimizing Cellular Networks Enabled with Renewal Energy via Strategic Learning.
Sohn, Insoo; Liu, Huaping; Ansari, Nirwan
2015-01-01
An important issue in the cellular industry is the rising energy cost and carbon footprint due to the rapid expansion of the cellular infrastructure. Greening cellular networks has thus attracted attention. Among the promising green cellular network techniques, the renewable energy-powered cellular network has drawn increasing attention as a critical element towards reducing carbon emissions due to massive energy consumption in the base stations deployed in cellular networks. Game theory is a branch of mathematics that is used to evaluate and optimize systems with multiple players with conflicting objectives and has been successfully used to solve various problems in cellular networks. In this paper, we model the green energy utilization and power consumption optimization problem of a green cellular network as a pilot power selection strategic game and propose a novel distributed algorithm based on a strategic learning method. The simulation results indicate that the proposed algorithm achieves correlated equilibrium of the pilot power selection game, resulting in optimum green energy utilization and power consumption reduction. PMID:26167934
Optimizing Cellular Networks Enabled with Renewal Energy via Strategic Learning
Sohn, Insoo; Liu, Huaping; Ansari, Nirwan
2015-01-01
An important issue in the cellular industry is the rising energy cost and carbon footprint due to the rapid expansion of the cellular infrastructure. Greening cellular networks has thus attracted attention. Among the promising green cellular network techniques, the renewable energy-powered cellular network has drawn increasing attention as a critical element towards reducing carbon emissions due to massive energy consumption in the base stations deployed in cellular networks. Game theory is a branch of mathematics that is used to evaluate and optimize systems with multiple players with conflicting objectives and has been successfully used to solve various problems in cellular networks. In this paper, we model the green energy utilization and power consumption optimization problem of a green cellular network as a pilot power selection strategic game and propose a novel distributed algorithm based on a strategic learning method. The simulation results indicate that the proposed algorithm achieves correlated equilibrium of the pilot power selection game, resulting in optimum green energy utilization and power consumption reduction. PMID:26167934
Renewable Energy Optimization Report for Naval Station Newport
Robichaud, R.; Mosey, G.; Olis, D.
2012-02-01
In 2008, the U.S. Environmental Protection Agency (EPA) launched the RE-Powering America's Land initiative to encourage the development of renewable energy (RE) on potentially contaminated land and mine sites. As part of this effort, EPA is collaborating with the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) to evaluate RE options at Naval Station (NAVSTA) Newport in Newport, Rhode Island. NREL's Renewable Energy Optimization (REO) tool was utilized to identify RE technologies that present the best opportunity for life-cycle cost-effective implementation while also serving to reduce energy-related carbon dioxide emissions and increase the percentage of RE used at NAVSTA Newport. The technologies included in REO are daylighting, wind, solar ventilation preheating (SVP), solar water heating, photovoltaics (PV), solar thermal (heating and electric), and biomass (gasification and cogeneration). The optimal mix of RE technologies depends on several factors including RE resources; technology cost and performance; state, utility, and federal incentives; and economic parameters (discount and inflation rates). Each of these factors was considered in this analysis. Technologies not included in REO that were investigated separately per NAVSTA Newport request include biofuels from algae, tidal power, and ground source heat pumps (GSHP).
Optimal Real-time Dispatch for Integrated Energy Systems
Firestone, Ryan Michael
2007-05-31
This report describes the development and application of a dispatch optimization algorithm for integrated energy systems (IES) comprised of on-site cogeneration of heat and electricity, energy storage devices, and demand response opportunities. This work is intended to aid commercial and industrial sites in making use of modern computing power and optimization algorithms to make informed, near-optimal decisions under significant uncertainty and complex objective functions. The optimization algorithm uses a finite set of randomly generated future scenarios to approximate the true, stochastic future; constraints are included that prevent solutions to this approximate problem from deviating from solutions to the actual problem. The algorithm is then expressed as a mixed integer linear program, to which a powerful commercial solver is applied. A case study of United States Postal Service Processing and Distribution Centers (P&DC) in four cities and under three different electricity tariff structures is conducted to (1) determine the added value of optimal control to a cogeneration system over current, heuristic control strategies; (2) determine the value of limited electric load curtailment opportunities, with and without cogeneration; and (3) determine the trade-off between least-cost and least-carbon operations of a cogeneration system. Key results for the P&DC sites studied include (1) in locations where the average electricity and natural gas prices suggest a marginally profitable cogeneration system, optimal control can add up to 67% to the value of the cogeneration system; optimal control adds less value in locations where cogeneration is more clearly profitable; (2) optimal control under real-time pricing is (a) more complicated than under typical time-of-use tariffs and (b) at times necessary to make cogeneration economic at all; (3) limited electric load curtailment opportunities can be more valuable as a compliment to the cogeneration system than alone; and
Applications of the Renewable Energy Network Optimization Tool
NASA Astrophysics Data System (ADS)
Alliss, R.; Link, R.; Apling, D.; Kiley, H.; Mason, M.; Darmenova, K.
2010-12-01
As the renewable energy industry continues to grow so does the requirement for atmospheric modeling and analysis tools to maximize both wind and solar power. Renewable energy generation is variable however; presenting challenges for electrical grid operation and requires a variety of measures to adequately firm power. These measures include the production of non-renewable generation during times when renewables are not available. One strategy for minimizing the variability of renewable energy production is site diversity. Assuming that a network of renewable energy systems feed a common electrical grid, site diversity ensures that when one system on the network has a reduction in generation others on the same grid make up the difference. The site-diversity strategy can be used to mitigate the intermittency in alternative energy production systems while still maximizing saleable energy. The Renewable Energy Network Optimization Tool (ReNOT) has recently been developed to study the merits of site optimization for wind farms. The modeling system has a plug-in architecture that allows us to accommodate a wide variety of renewable energy system designs and performance metrics. The Weather Research and Forecasting (WRF) mesoscale model is applied to generate high-resolution wind databases to support the site selection of wind farms. These databases are generated on High Performance Computing systems such as the Rocky Mountain Supercomputing Center (RMSC). The databases are then accessed by ReNOT and an optimized site selection is developed. We can accommodate numerous constraints (e.g., number of sites, the geographic extent of the optimization, proximity to high-voltage transport lines, etc.). As part of our collaboration with RMSC and the State of Montana a study was performed to estimate the optimal locations of a network of wind farms. Comparisons were made to four existing wind farm locations in Montana including Glacier with a 210 MW name plate capacity, Horseshoe
NASA Astrophysics Data System (ADS)
Dimas, Panagiotis; Bouziotas, Dimitris; Efstratiadis, Andreas; Koutsoyiannis, Demetris
2014-05-01
Hydropower with pumped storage is a proven technology with very high efficiency that offers a unique large-scale energy buffer. Energy storage is employed by pumping water upstream to take advantage of the excess of produced energy (e.g. during night) and next retrieving this water to generate hydro-power during demand peaks. Excess energy occurs due to other renewables (wind, solar) whose power fluctuates in an uncontrollable manner. By integrating these with hydroelectric plants with pumped storage facilities we can form autonomous hybrid renewable energy systems. The optimal planning and management thereof requires a holistic approach, where uncertainty is properly represented. In this context, a novel framework is proposed, based on stochastic simulation and optimization. This is tested in an existing hydrosystem of Greece, considering its combined operation with a hypothetical wind power system, for which we seek the optimal design to ensure the most beneficial performance of the overall scheme.
Steam distribution and energy delivery optimization using wireless sensors
Olama, Mohammed M; Allgood, Glenn O; Kuruganti, Phani Teja; Sukumar, Sreenivas R; Djouadi, Seddik M; Lake, Joe E
2011-01-01
The Extreme Measurement Communications Center at Oak Ridge National Laboratory (ORNL) explores the deployment of a wireless sensor system with a real-time measurement-based energy efficiency optimization framework in the ORNL campus. With particular focus on the 12-mile long steam distribution network in our campus, we propose an integrated system-level approach to optimize the energy delivery within the steam distribution system. We address the goal of achieving significant energy-saving in steam lines by monitoring and acting on leaking steam valves/traps. Our approach leverages an integrated wireless sensor and real-time monitoring capabilities. We make assessments on the real-time status of the distribution system by mounting acoustic sensors on the steam pipes/traps/valves and observe the state measurements of these sensors. Our assessments are based on analysis of the wireless sensor measurements. We describe Fourier-spectrum based algorithms that interpret acoustic vibration sensor data to characterize flows and classify the steam system status. We are able to present the sensor readings, steam flow, steam trap status and the assessed alerts as an interactive overlay within a web-based Google Earth geographic platform that enables decision makers to take remedial action. We believe our demonstration serves as an instantiation of a platform that extends implementation to include newer modalities to manage water flow, sewage and energy consumption.
Steam distribution and energy delivery optimization using wireless sensors
NASA Astrophysics Data System (ADS)
Olama, Mohammed M.; Allgood, Glenn O.; Kuruganti, Teja P.; Sukumar, Sreenivas R.; Djouadi, Seddik M.; Lake, Joe E.
2011-05-01
The Extreme Measurement Communications Center at Oak Ridge National Laboratory (ORNL) explores the deployment of a wireless sensor system with a real-time measurement-based energy efficiency optimization framework in the ORNL campus. With particular focus on the 12-mile long steam distribution network in our campus, we propose an integrated system-level approach to optimize the energy delivery within the steam distribution system. We address the goal of achieving significant energy-saving in steam lines by monitoring and acting on leaking steam valves/traps. Our approach leverages an integrated wireless sensor and real-time monitoring capabilities. We make assessments on the real-time status of the distribution system by mounting acoustic sensors on the steam pipes/traps/valves and observe the state measurements of these sensors. Our assessments are based on analysis of the wireless sensor measurements. We describe Fourier-spectrum based algorithms that interpret acoustic vibration sensor data to characterize flows and classify the steam system status. We are able to present the sensor readings, steam flow, steam trap status and the assessed alerts as an interactive overlay within a web-based Google Earth geographic platform that enables decision makers to take remedial action. We believe our demonstration serves as an instantiation of a platform that extends implementation to include newer modalities to manage water flow, sewage and energy consumption.
Optimal geometry of an axisymmetric wave energy converter
NASA Astrophysics Data System (ADS)
Edwards, Emma; Yue, Dick K. P.; Vortical Flow Research Laboratory Team
2015-11-01
There have been a number of theoretical, experimental and pilot-scale studies on wave energy converters with varying shapes and designs, but due to the complex nature of wave-body hydrodynamics, as yet there is not one single three-dimensional shape that is agreed-upon to be optimal for wave power extraction. Our objective is to determine the optimal geometry to maximize power uptake over a spectrum of incident waves. As an initial investigation, we consider an axisymmetric floating wave power extraction device operating in heave. We assume linear wave conditions. The body geometry is described by smooth polynomial basis functions and is allowed to be completely general, subject to simple constraints. We consider a linear power uptake with a fixed damping coefficient (which could be optimized). For each frequency in the spectrum, hydrodynamic coefficients are calculated using a linear frequency-domain panel method. Then, for a specific incident wave spectrum, maximal extractable power is integrated over the entire spectrum. We will discuss the optimal geometry and associated maximum power for different geometrical constraints and wave conditions.
Classifier-Guided Sampling for Complex Energy System Optimization
Backlund, Peter B.; Eddy, John P.
2015-09-01
This report documents the results of a Laboratory Directed Research and Development (LDRD) effort enti tled "Classifier - Guided Sampling for Complex Energy System Optimization" that was conducted during FY 2014 and FY 2015. The goal of this proj ect was to develop, implement, and test major improvements to the classifier - guided sampling (CGS) algorithm. CGS is type of evolutionary algorithm for perform ing search and optimization over a set of discrete design variables in the face of one or more objective functions. E xisting evolutionary algorithms, such as genetic algorithms , may require a large number of o bjecti ve function evaluations to identify optimal or near - optimal solutions . Reducing the number of evaluations can result in significant time savings, especially if the objective function is computationally expensive. CGS reduce s the evaluation count by us ing a Bayesian network classifier to filter out non - promising candidate designs , prior to evaluation, based on their posterior probabilit ies . In this project, b oth the single - objective and multi - objective version s of the CGS are developed and tested on a set of benchm ark problems. As a domain - specific case study, CGS is used to design a microgrid for use in islanded mode during an extended bulk power grid outage.
Analog Ensemble Methodology: Expansion and Optimization for Renewable Energy Applications
NASA Astrophysics Data System (ADS)
Harding, L.; Cervone, G.; Delle Monache, L.
2015-12-01
Renewable energy is fundamental for sustaining and developing society. Solar and wind energy are promising sources because of their decreased environmental impact relative to conventional energy sources, improved efficiency, and increased use. A key challenge with renewable energy production is the generation of accurate renewable energy forecasts at varying spatial and temporal scales to assist utility companies in effective energy management. Specifically, this research applies the Analog Ensemble (AnEn) methodology to short-term (0-48 hour) wind speed forecasting for power generation and short-term (0-72) hour solar power measured (PM) output predictions. AnEn uses a set of past observations corresponding to the best analogs of a deterministic numerical weather prediction model to generate a probability distribution of future atmospheric states: an ensemble of analogs. Currently the AnEn methodology equally weights predictors and only handles 1D(time). We determine an optimal distribution of predictor weights based upon parameter characteristics, investigate spatial variations in the application of the methodology and develop a theory expanding the methodology into 2D. The AnEn methodology improves short-term prediction accuracy, decreases computational costs and provides uncertainty quantification allowing utility companies to manage over- or under power generation for renewable energy sources.
Optimal aeroassisted coplanar orbital transfer using an energy model
NASA Technical Reports Server (NTRS)
Halyo, Nesim; Taylor, Deborah B.
1989-01-01
The atmospheric portion of the trajectories for the aeroassisted coplanar orbit transfer was investigated. The equations of motion for the problem are expressed using reduced order model and total vehicle energy, kinetic plus potential, as the independent variable rather than time. The order reduction is achieved analytically without an approximation of the vehicle dynamics. In this model, the problem of coplanar orbit transfer is seen as one in which a given amount of energy must be transferred from the vehicle to the atmosphere during the trajectory without overheating the vehicle. An optimal control problem is posed where a linear combination of the integrated square of the heating rate and the vehicle drag is the cost function to be minimized. The necessary conditions for optimality are obtained. These result in a 4th order two-point-boundary-value problem. A parametric study of the optimal guidance trajectory in which the proportion of the heating rate term versus the drag varies is made. Simulations of the guidance trajectories are presented.
Optimal boson energy for superconductivity in the Holstein model
NASA Astrophysics Data System (ADS)
Lin, Chungwei; Wang, Bingnan; Teo, Koon Hoo
2016-06-01
We examine the superconducting solution in the Holstein model, where the conduction electrons couple to the dispersionless boson fields, using the Migdal-Eliashberg theory and dynamical mean field theory. Although different in numerical values, both methods imply the existence of an optimal boson energy for superconductivity at a given electron-boson coupling. This nonmonotonous behavior can be understood as an interplay between the polaron and superconducting physics, as the electron-boson coupling is the origin of the superconductor, but at the same time traps the conduction electrons making the system more insulating. Our calculation provides a simple explanation of the recent experiment on sulfur hydride, where an optimal pressure for the superconductivity was observed. The validities of both methods are discussed.
Design optimization of superconducting magnetic energy storage coil
NASA Astrophysics Data System (ADS)
Bhunia, Uttam; Saha, Subimal; Chakrabarti, Alok
2014-05-01
An optimization formulation has been developed for a superconducting magnetic energy storage (SMES) solenoid-type coil with niobium titanium (Nb-Ti) based Rutherford-type cable that minimizes the cryogenic refrigeration load into the cryostat. Minimization of refrigeration load reduces the operating cost and opens up the possibility to adopt helium re-condensing system using cryo-cooler especially for small-scale SMES system. Dynamic refrigeration load during charging or discharging operational mode of the coil dominates over steady state load. The paper outlines design optimization with practical design constraints like actual critical characteristics of the superconducting cable, maximum allowable hoop stress on winding, etc., with the objective to minimize refrigeration load into the SMES cryostat. Effect of design parameters on refrigeration load is also investigated.
Total energy control system autopilot design with constrained parameter optimization
NASA Technical Reports Server (NTRS)
Ly, Uy-Loi; Voth, Christopher
1990-01-01
A description is given of the application of a multivariable control design method (SANDY) based on constrained parameter optimization to the design of a multiloop aircraft flight control system. Specifically, the design method is applied to the direct synthesis of a multiloop AFCS inner-loop feedback control system based on total energy control system (TECS) principles. The design procedure offers a structured approach for the determination of a set of stabilizing controller design gains that meet design specifications in closed-loop stability, command tracking performance, disturbance rejection, and limits on control activities. The approach can be extended to a broader class of multiloop flight control systems. Direct tradeoffs between many real design goals are rendered systematic by proper formulation of the design objectives and constraints. Satisfactory designs are usually obtained in few iterations. Performance characteristics of the optimized TECS design have been improved, particularly in the areas of closed-loop damping and control activity in the presence of turbulence.
Energy efficiency analysis and optimization for mobile platforms
NASA Astrophysics Data System (ADS)
Metri, Grace Camille
The introduction of mobile devices changed the landscape of computing. Gradually, these devices are replacing traditional personal computer (PCs) to become the devices of choice for entertainment, connectivity, and productivity. There are currently at least 45.5 million people in the United States who own a mobile device, and that number is expected to increase to 1.5 billion by 2015. Users of mobile devices expect and mandate that their mobile devices have maximized performance while consuming minimal possible power. However, due to the battery size constraints, the amount of energy stored in these devices is limited and is only growing by 5% annually. As a result, we focused in this dissertation on energy efficiency analysis and optimization for mobile platforms. We specifically developed SoftPowerMon, a tool that can power profile Android platforms in order to expose the power consumption behavior of the CPU. We also performed an extensive set of case studies in order to determine energy inefficiencies of mobile applications. Through our case studies, we were able to propose optimization techniques in order to increase the energy efficiency of mobile devices and proposed guidelines for energy-efficient application development. In addition, we developed BatteryExtender, an adaptive user-guided tool for power management of mobile devices. The tool enables users to extend battery life on demand for a specific duration until a particular task is completed. Moreover, we examined the power consumption of System-on-Chips (SoCs) and observed the impact on the energy efficiency in the event of offloading tasks from the CPU to the specialized custom engines. Based on our case studies, we were able to demonstrate that current software-based power profiling techniques for SoCs can have an error rate close to 12%, which needs to be addressed in order to be able to optimize the energy consumption of the SoC. Finally, we summarize our contributions and outline possible
Nonlinear optimization of acoustic energy harvesting using piezoelectric devices.
Lallart, Mickaeël; Guyomar, Daniel; Richard, Claude; Petit, Lionel
2010-11-01
In the first part of the paper, a single degree-of-freedom model of a vibrating membrane with piezoelectric inserts is introduced and is initially applied to the case when a plane wave is incident with frequency close to one of the resonance frequencies. The model is a prototype of a device which converts ambient acoustical energy to electrical energy with the use of piezoelectric devices. The paper then proposes an enhancement of the energy harvesting process using a nonlinear processing of the output voltage of piezoelectric actuators, and suggests that this improves the energy conversion and reduces the sensitivity to frequency drifts. A theoretical discussion is given for the electrical power that can be expected making use of various models. This and supporting experimental results suggest that a nonlinear optimization approach allows a gain of up to 10 in harvested energy and a doubling of the bandwidth. A model is introduced in the latter part of the paper for predicting the behavior of the energy-harvesting device with changes in acoustic frequency, this model taking into account the damping effect and the frequency changes introduced by the nonlinear processes in the device. PMID:21110569
26 CFR 1.61-22 - Taxation of split-dollar life insurance arrangements.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Taxation of split-dollar life insurance..., and Taxable Income § 1.61-22 Taxation of split-dollar life insurance arrangements. (a) Scope—(1) In general. This section provides rules for the taxation of a split-dollar life insurance arrangement...
26 CFR 25.2701-5 - Adjustments to mitigate double taxation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Adjustments to mitigate double taxation. 25....2701-5 Adjustments to mitigate double taxation. (a) Reduction of transfer tax base—(1) In general. This... − $187,500). (g) Double taxation otherwise avoided. No reduction is available under this section if—...
26 CFR 521.117 - Claims in cases of double taxation.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 19 2014-04-01 2010-04-01 true Claims in cases of double taxation. 521.117... of Denmark and of Danish Corporations § 521.117 Claims in cases of double taxation. Under Article XX... in double taxation in respect of any of the taxes to which the convention relates, the taxpayer...
26 CFR 521.117 - Claims in cases of double taxation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 19 2010-04-01 2010-04-01 false Claims in cases of double taxation. 521.117... of Denmark and of Danish Corporations § 521.117 Claims in cases of double taxation. Under Article XX... in double taxation in respect of any of the taxes to which the convention relates, the taxpayer...
26 CFR 521.117 - Claims in cases of double taxation.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 19 2011-04-01 2010-04-01 true Claims in cases of double taxation. 521.117... of Denmark and of Danish Corporations § 521.117 Claims in cases of double taxation. Under Article XX... in double taxation in respect of any of the taxes to which the convention relates, the taxpayer...
26 CFR 25.2701-5 - Adjustments to mitigate double taxation.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 14 2013-04-01 2013-04-01 false Adjustments to mitigate double taxation. 25....2701-5 Adjustments to mitigate double taxation. (a) Reduction of transfer tax base—(1) In general. This... − $187,500). (g) Double taxation otherwise avoided. No reduction is available under this section if—...
26 CFR 25.2701-5 - Adjustments to mitigate double taxation.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 14 2014-04-01 2013-04-01 true Adjustments to mitigate double taxation. 25.2701... Adjustments to mitigate double taxation. (a) Reduction of transfer tax base—(1) In general. This section... − $187,500). (g) Double taxation otherwise avoided. No reduction is available under this section if—...
26 CFR 25.2701-5 - Adjustments to mitigate double taxation.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 14 2011-04-01 2010-04-01 true Adjustments to mitigate double taxation. 25.2701... Adjustments to mitigate double taxation. (a) Reduction of transfer tax base—(1) In general. This section... − $187,500). (g) Double taxation otherwise avoided. No reduction is available under this section if—...
26 CFR 521.117 - Claims in cases of double taxation.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 19 2013-04-01 2010-04-01 true Claims in cases of double taxation. 521.117... of Denmark and of Danish Corporations § 521.117 Claims in cases of double taxation. Under Article XX... in double taxation in respect of any of the taxes to which the convention relates, the taxpayer...
26 CFR 521.117 - Claims in cases of double taxation.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 19 2012-04-01 2010-04-01 true Claims in cases of double taxation. 521.117... of Denmark and of Danish Corporations § 521.117 Claims in cases of double taxation. Under Article XX... in double taxation in respect of any of the taxes to which the convention relates, the taxpayer...
26 CFR 25.2701-5 - Adjustments to mitigate double taxation.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 14 2012-04-01 2012-04-01 false Adjustments to mitigate double taxation. 25....2701-5 Adjustments to mitigate double taxation. (a) Reduction of transfer tax base—(1) In general. This... − $187,500). (g) Double taxation otherwise avoided. No reduction is available under this section if—...
26 CFR 1.468B-2 - Taxation of qualified settlement funds and related administrative requirements.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Taxation of qualified settlement funds and... Taken § 1.468B-2 Taxation of qualified settlement funds and related administrative requirements. (a) In...) of this section is in lieu of any other taxation of the income of a qualified settlement fund...
26 CFR 1.852-2 - Method of taxation of regulated investment companies.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Method of taxation of regulated investment... Trusts § 1.852-2 Method of taxation of regulated investment companies. (a) Imposition of normal tax and... for partially tax-exempt interest provided by section 242. (b) Taxation of capital gains—(1)...
22 CFR 40.105 - Former citizens who renounced citizenship to avoid taxation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... avoid taxation. 40.105 Section 40.105 Foreign Relations DEPARTMENT OF STATE VISAS REGULATIONS PERTAINING... Miscellaneous § 40.105 Former citizens who renounced citizenship to avoid taxation. An alien who is a former... avoid United States taxation, is ineligible for a visa under INA 212(a)(10)(E)....
26 CFR 1.995-1 - Taxation of DISC income to shareholders.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 10 2010-04-01 2010-04-01 false Taxation of DISC income to shareholders. 1.995...) INCOME TAX (CONTINUED) INCOME TAXES Domestic International Sales Corporations § 1.995-1 Taxation of DISC... to taxation on the earnings and profits of the DISC in accordance with the provisions of chapter 1...
26 CFR 1.403(b)-7 - Taxation of distributions and benefits.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 5 2010-04-01 2010-04-01 false Taxation of distributions and benefits. 1.403(b... Taxation of distributions and benefits. (a) General rules for when amounts are included in gross income... arrangements and other eligible retirement plans—(1) Timing of taxation of rollovers. In accordance...
Optimizing energy for a 'green' vaccine supply chain.
Lloyd, John; McCarney, Steve; Ouhichi, Ramzi; Lydon, Patrick; Zaffran, Michel
2015-02-11
This paper describes an approach piloted in the Kasserine region of Tunisia to increase the energy efficiency of the distribution of vaccines and temperature sensitive drugs. The objectives of an approach, known as the 'net zero energy' (NZE) supply chain were demonstrated within the first year of operation. The existing distribution system was modified to store vaccines and medicines in the same buildings and to transport them according to pre-scheduled and optimized delivery circuits. Electric utility vehicles, dedicated to the integrated delivery of vaccines and medicines, improved the regularity and reliability of the supply chains. Solar energy, linked to the electricity grid at regional and district stores, supplied over 100% of consumption meeting all energy needs for storage, cooling and transportation. Significant benefits to the quality and costs of distribution were demonstrated. Supply trips were scheduled, integrated and reliable, energy consumption was reduced, the recurrent cost of electricity was eliminated and the release of carbon to the atmosphere was reduced. Although the initial capital cost of scaling up implementation of NZE remain high today, commercial forecasts predict cost reduction for solar energy and electric vehicles that may permit a step-wise implementation over the next 7-10 years. Efficiency in the use of energy and in the deployment of transport is already a critical component of distribution logistics in both private and public sectors of industrialized countries. The NZE approach has an intensified rationale in countries where energy costs threaten the maintenance of public health services in areas of low population density. In these countries where the mobility of health personnel and timely arrival of supplies is at risk, NZE has the potential to reduce energy costs and release recurrent budget to other needs of service delivery while also improving the supply chain. PMID:25444811
Computer aided optimal design of compressed air energy storage systems
NASA Astrophysics Data System (ADS)
Ahrens, F. W.; Sharma, A.; Ragsdell, K. M.
1980-07-01
An automated procedure for the design of Compressed Air Energy Storage (CAES) systems is presented. The procedure relies upon modern nonlinear programming algorithms, decomposition theory, and numerical models of the various system components. Two modern optimization methods are employed; BIAS, a Method of Multipliers code and OPT, a Generalized Reduced Gradient code. The procedure is demonstrated by the design of a CAES facility employing the Media, Illinois Galesville aquifer as the reservoir. The methods employed produced significant reduction in capital and operating cost, and in number of aquifer wells required.
Energy and efficiency optimization of a Brownian heat engine
NASA Astrophysics Data System (ADS)
Bekele, Mulugeta; Yalew, Yeneneh
2007-03-01
A simple Brownian heat engine is modeled as a Brownian particle moving in an external sawtooth potential (with or without) load assisted by the thermal kick it gets from alternately placed hot and cold heat reservoirs along its path. We get closed form expression for its current in terms of the parameters characterizing the model. After analyzing the way it consumes energy to do useful work, we also get closed form expressions for its efficiency as well as for its coefficient of performance when the engine performs as a refrigerator. Recently suggested optimization criteria enables us to exhaustively explore and compare the different operating conditions of the engine.
Optimizing energy for a ‘green’ vaccine supply chain
Lloyd, John; McCarney, Steve; Ouhichi, Ramzi; Lydon, Patrick; Zaffran, Michel
2015-01-01
This paper describes an approach piloted in the Kasserine region of Tunisia to increase the energy efficiency of the distribution of vaccines and temperature sensitive drugs. The objectives of an approach, known as the ‘net zero energy’ (NZE) supply chain were demonstrated within the first year of operation. The existing distribution system was modified to store vaccines and medicines in the same buildings and to transport them according to pre-scheduled and optimized delivery circuits. Electric utility vehicles, dedicated to the integrated delivery of vaccines and medicines, improved the regularity and reliability of the supply chains. Solar energy, linked to the electricity grid at regional and district stores, supplied over 100% of consumption meeting all energy needs for storage, cooling and transportation. Significant benefits to the quality and costs of distribution were demonstrated. Supply trips were scheduled, integrated and reliable, energy consumption was reduced, the recurrent cost of electricity was eliminated and the release of carbon to the atmosphere was reduced. Although the initial capital cost of scaling up implementation of NZE remain high today, commercial forecasts predict cost reduction for solar energy and electric vehicles that may permit a step-wise implementation over the next 7–10 years. Efficiency in the use of energy and in the deployment of transport is already a critical component of distribution logistics in both private and public sectors of industrialized countries. The NZE approach has an intensified rationale in countries where energy costs threaten the maintenance of public health services in areas of low population density. In these countries where the mobility of health personnel and timely arrival of supplies is at risk, NZE has the potential to reduce energy costs and release recurrent budget to other needs of service delivery while also improving the supply chain. PMID:25444811
Weather forecast-based optimization of integrated energy systems.
Zavala, V. M.; Constantinescu, E. M.; Krause, T.; Anitescu, M.
2009-03-01
In this work, we establish an on-line optimization framework to exploit detailed weather forecast information in the operation of integrated energy systems, such as buildings and photovoltaic/wind hybrid systems. We first discuss how the use of traditional reactive operation strategies that neglect the future evolution of the ambient conditions can translate in high operating costs. To overcome this problem, we propose the use of a supervisory dynamic optimization strategy that can lead to more proactive and cost-effective operations. The strategy is based on the solution of a receding-horizon stochastic dynamic optimization problem. This permits the direct incorporation of economic objectives, statistical forecast information, and operational constraints. To obtain the weather forecast information, we employ a state-of-the-art forecasting model initialized with real meteorological data. The statistical ambient information is obtained from a set of realizations generated by the weather model executed in an operational setting. We present proof-of-concept simulation studies to demonstrate that the proposed framework can lead to significant savings (more than 18% reduction) in operating costs.
Optimization of exciton trapping in energy transfer processes.
Cao, Jianshu; Silbey, Robert J
2009-12-17
In this paper, we establish optimal conditions for maximal energy transfer efficiency using solutions for multilevel systems and interpret these analytical solutions with more intuitive kinetic networks resulting from a systematic mapping procedure. The mapping procedure defines an effective hopping rate as the leading order picture and nonlocal kinetic couplings as the quantum correction, hence leading to a rigorous separation of thermal hopping and coherent transfer useful for visualizing pathway connectivity and interference in quantum networks. As a result of these calculations, the dissipative effects of the surrounding environments can be optimized to yield the maximal efficiency, and modulation of the efficiency can be achieved using the cumulative quantum phase along any closed loops. The optimal coupling of the system and its environments is interpreted with the generic mechanisms: (i) balancing localized trapping and delocalized coherence, (ii) reducing the effective detuning via homogeneous line-broadening, (iii) suppressing the destructive interference in nonlinear network configurations, and (iv) controlling phase modulation in closed loop configurations. Though these results are obtained for simple model systems, the physics thus derived provides insights into the working of light harvesting systems, and the approaches thus developed apply to large-scale computation. PMID:19929005
Optimal strategies for electric energy contract decision making
NASA Astrophysics Data System (ADS)
Song, Haili
2000-10-01
The power industry restructuring in various countries in recent years has created an environment where trading of electric energy is conducted in a market environment. In such an environment, electric power companies compete for the market share through spot and bilateral markets. Being profit driven, electric power companies need to make decisions on spot market bidding, contract evaluation, and risk management. New methods and software tools are required to meet these upcoming needs. In this research, bidding strategy and contract pricing are studied from a market participant's viewpoint; new methods are developed to guide a market participant in spot and bilateral market operation. A supplier's spot market bidding decision is studied. Stochastic optimization is formulated to calculate a supplier's optimal bids in a single time period. This decision making problem is also formulated as a Markov Decision Process. All the competitors are represented by their bidding parameters with corresponding probabilities. A systematic method is developed to calculate transition probabilities and rewards. The optimal strategy is calculated to maximize the expected reward over a planning horizon. Besides the spot market, a power producer can also trade in the bilateral markets. Bidding strategies in a bilateral market are studied with game theory techniques. Necessary and sufficient conditions of Nash Equilibrium (NE) bidding strategy are derived based on the generators' cost and the loads' willingness to pay. The study shows that in any NE, market efficiency is achieved. Furthermore, all Nash equilibria are revenue equivalent for the generators. The pricing of "Flexible" contracts, which allow delivery flexibility over a period of time with a fixed total amount of electricity to be delivered, is analyzed based on the no-arbitrage pricing principle. The proposed algorithm calculates the price based on the optimality condition of the stochastic optimization formulation
Oneida Tribe of Indians of Wisconsin Energy Optimization Model
Troge, Michael
2014-12-01
Oneida Nation is located in Northeast Wisconsin. The reservation is approximately 96 square miles (8 miles x 12 miles), or 65,000 acres. The greater Green Bay area is east and adjacent to the reservation. A county line roughly splits the reservation in half; the west half is in Outagamie County and the east half is in Brown County. Land use is predominantly agriculture on the west 2/3 and suburban on the east 1/3 of the reservation. Nearly 5,000 tribally enrolled members live in the reservation with a total population of about 21,000. Tribal ownership is scattered across the reservation and is about 23,000 acres. Currently, the Oneida Tribe of Indians of Wisconsin (OTIW) community members and facilities receive the vast majority of electrical and natural gas services from two of the largest investor-owned utilities in the state, WE Energies and Wisconsin Public Service. All urban and suburban buildings have access to natural gas. About 15% of the population and five Tribal facilities are in rural locations and therefore use propane as a primary heating fuel. Wood and oil are also used as primary or supplemental heat sources for a small percent of the population. Very few renewable energy systems, used to generate electricity and heat, have been installed on the Oneida Reservation. This project was an effort to develop a reasonable renewable energy portfolio that will help Oneida to provide a leadership role in developing a clean energy economy. The Energy Optimization Model (EOM) is an exploration of energy opportunities available to the Tribe and it is intended to provide a decision framework to allow the Tribe to make the wisest choices in energy investment with an organizational desire to establish a renewable portfolio standard (RPS).
Optimizing the Electrical Power in an Energy Harvesting System
NASA Astrophysics Data System (ADS)
Coccolo, Mattia; Litak, Grzegorz; Seoane, Jesús M.; Sanjuán, Miguel A. F.
In this paper, we study the vibrational resonance (VR) phenomenon as a useful mechanism for energy harvesting purposes. A system, driven by a low frequency and a high frequency forcing, can give birth to the vibrational resonance phenomenon, when the two forcing amplitudes resonate and a maximum in amplitude is reached. We apply this idea to a bistable oscillator that can convert environmental kinetic energy into electrical energy, that is, an energy harvester. Normally, the VR phenomenon is studied in terms of the forcing amplitudes or of the frequencies, that are not always easy to adjust and change. Here, we study the VR generated by tuning another parameter that is possible to manipulate when the forcing values depend on the environmental conditions. We have investigated the dependence of the maximum response due to the VR for small and large variations in the forcing amplitudes and frequencies. Besides, we have plotted color coded figures in the space of the two forcing amplitudes, in which it is possible to appreciate different patterns in the electrical power generated by the system. These patterns provide useful information on the forcing amplitudes in order to produce the optimal electrical power.
Exploiting node mobility for energy optimization in wireless sensor networks
NASA Astrophysics Data System (ADS)
El-Moukaddem, Fatme Mohammad
Wireless Sensor Networks (WSNs) have become increasingly available for data-intensive applications such as micro-climate monitoring, precision agriculture, and audio/video surveillance. A key challenge faced by data-intensive WSNs is to transmit the sheer amount of data generated within an application's lifetime to the base station despite the fact that sensor nodes have limited power supplies such as batteries or small solar panels. The availability of numerous low-cost robotic units (e.g. Robomote and Khepera) has made it possible to construct sensor networks consisting of mobile sensor nodes. It has been shown that the controlled mobility offered by mobile sensors can be exploited to improve the energy efficiency of a network. In this thesis, we propose schemes that use mobile sensor nodes to reduce the energy consumption of data-intensive WSNs. Our approaches differ from previous work in two main aspects. First, our approaches do not require complex motion planning of mobile nodes, and hence can be implemented on a number of low-cost mobile sensor platforms. Second, we integrate the energy consumption due to both mobility and wireless communications into a holistic optimization framework. We consider three problems arising from the limited energy in the sensor nodes. In the first problem, the network consists of mostly static nodes and contains only a few mobile nodes. In the second and third problems, we assume essentially that all nodes in the WSN are mobile. We first study a new problem called max-data mobile relay configuration (MMRC ) that finds the positions of a set of mobile sensors, referred to as relays, that maximize the total amount of data gathered by the network during its lifetime. We show that the MMRC problem is surprisingly complex even for a trivial network topology due to the joint consideration of the energy consumption of both wireless communication and mechanical locomotion. We present optimal MMRC algorithms and practical distributed
Demontration of Integrated Optimization Software at the Baldwin Energy Complex
Rob James; John McDermott; Sanjay Patnaik; Steve Piche`
2009-01-07
This project encompassed the design, development, and demonstration of integrated online optimization systems at Dynegy Midwest Generation's Baldwin Energy Complex (BEC) located in Baldwin, Illinois. The overall project objective was to improve coal-based generation's emission profile, efficiency, maintenance requirements and plant asset life in order to enhance the long-term viability of the United States abundant coal resources. Five separate but integrated optimization products were developed, addressing combustion, sootblowing, SCR operations, overall unit thermal performance, and plant-wide availability optimization. Optimization results are inherently unit-specific and cannot be known for a particular generating unit in advance. However, NeuCo believed that the following were reasonable targets for the completed, integrated set of products: Furnace NOx reduction improvement by 5%, Heat rate improvement by 1.5%, Increase of annual Available MWh by 1.5%, Commensurate reductions in greenhouse gases, mercury, and particulates; and Commensurate increases in profitability from lower costs, improved reliability, and greater commercial availability. The goal during Phase I was to establish each system and demonstrate their integration in unified plant optimization. Efforts during Phase I focused on: (1) developing, deploying, integrating, and testing prototypes for each of the five products; (2) identifying and addressing issues required for the products to integrate with plant operations; and (3) systematically collecting and assimilating feedback to improve subsequent product releases. As described in the Phase II continuation application NeuCo successfully achieved the goal for Phase I. The goal of Phase II was to improve upon the products installed and tested in Phase I and to quantify the benefits of the integrated system. As this report documents, NeuCo has also successfully achieved the goal for Phase II. The overall results of the project, compared with the
Optimal mixing and optimal stirring for fixed energy, fixed power, or fixed palenstrophy flows
NASA Astrophysics Data System (ADS)
Lunasin, Evelyn; Lin, Zhi; Novikov, Alexei; Mazzucato, Anna; Doering, Charles R.
2012-11-01
We consider passive scalar mixing by a prescribed divergence-free velocity vector field in a periodic box and address the following question: Starting from a given initial inhomogeneous distribution of passive tracers, and given a certain energy budget, power budget, or finite palenstrophy budget, what incompressible flow field best mixes the scalar quantity? We focus on the optimal stirring strategy recently proposed by Lin et al. ["Optimal stirring strategies for passive scalar mixing," J. Fluid Mech. 675, 465 (2011)], 10.1017/S0022112011000292 that determines the flow field that instantaneously maximizes the depletion of the H-1 mix-norm. In this work, we bridge some of the gap between the best available a priori analysis and simulation results. After recalling some previous analysis, we present an explicit example demonstrating finite-time perfect mixing with a finite energy constraint on the stirring flow. On the other hand, using a recent result by Wirosoetisno et al. ["Long time stability of a classical efficient scheme for two dimensional Navier-Stokes equations," SIAM J. Numer. Anal. 50(1), 126-150 (2012)], 10.1137/110834901 we establish that the H-1 mix-norm decays at most exponentially in time if the two-dimensional incompressible flow is constrained to have constant palenstrophy. Finite-time perfect mixing is thus ruled out when too much cost is incurred by small scale structures in the stirring. Direct numerical simulations in two dimensions suggest the impossibility of finite-time perfect mixing for flows with fixed power constraint and we conjecture an exponential lower bound on the H-1 mix-norm in this case. We also discuss some related problems from other areas of analysis that are similarly suggestive of an exponential lower bound for the H-1 mix-norm.
Thermal modeling and optimization of a thermally matched energy harvester
NASA Astrophysics Data System (ADS)
Boughaleb, J.; Arnaud, A.; Cottinet, P. J.; Monfray, S.; Gelenne, P.; Kermel, P.; Quenard, S.; Boeuf, F.; Guyomar, D.; Skotnicki, T.
2015-08-01
The interest in energy harvesting devices has grown with the development of wireless sensors requiring small amounts of energy to function. The present article addresses the thermal investigation of a coupled piezoelectric and bimetal-based heat engine. The thermal energy harvester in question converts low-grade heat flows into electrical charges by achieving a two-step conversion mechanism for which the key point is the ability to maintain a significant thermal gradient without any heat sink. Many studies have previously focused on the electrical properties of this innovative device for energy harvesting but until now, no thermal modeling has been able to describe the device specificities or improve its thermal performances. The research reported in this paper focuses on the modeling of the harvester using an equivalent electrical circuit approach. It is shown that the knowledge of the thermal properties inside the device and a good comprehension of its heat exchange with the surrounding play a key role in the optimization procedure. To validate the thermal modeling, finite element analyses as well as experimental measurements on a hot plate were carried out and the techniques were compared. The proposed model provided a practical guideline for improving the generator design to obtain a thermally matched energy harvester that can function over a wide range of hot source temperatures for the same bimetal. A direct application of this study has been implemented on scaled structures to maintain an important temperature difference between the cold surface and the hot reservoir. Using the equations of the thermal model, predictions of the thermal properties were evaluated depending on the scaling factor and solutions for future thermal improvements are presented.
DOE`s nuclear energy plant optimization program
Harrison, D.; Savage, C.D.; Singh, B.P.
1999-09-01
In December 1997, the United States agreed to the Kyoto Protocol on Climate Change that outlines specific greenhouse gas emissions reduction requirements. A key element of this protocol is binding emissions targets and timetables. The Protocol calls for the United States to reach emissions targets 7% below 1990 emissions levels over the 5-yr period from 2008 to 2012. A key element to achieving this goal will be the continued safe and economic operation of the Nation`s 104 nuclear power plants. These plants provide >20% of the Nation`s electricity, and nearly one-half of the 50 states receive >25% of their electricity from nuclear power. DOE`s current Strategic Plan specifies that the United States maintain its nuclear energy option and improve the efficiency of existing plants as part of its energy portfolio, in the interest of national security. As a result, DOE proposed two new nuclear energy R and D programs for fiscal year (FY) 1999: the Nuclear Energy Research Initiative (NERI), a peer-reviewed, competitively selected R and D program in advanced concepts, and the Nuclear Energy Plant Optimization Program (NEPO). NERI was authorized and received initial funding of $19 million for its first year. NEPO was not funded in 1999 but has been reintroduced in the FY 2000 budget request. NEPO will be a jointly funded R and D program with industry through the Electric Power Research Institute (EPRI) and will address those issues that could hinder continued safe operation of the Nation`s operating nuclear power plants. The FY 2000 funding request to Congress for NEPO is $5 million.
First Nations Communities and Tobacco Taxation: A Commentary
ERIC Educational Resources Information Center
Samji, Hasina; Wardman, Dennis
2009-01-01
Taxation of tobacco is a widely used strategy that promotes smoking cessation among adults and reduces cigarette consumption among continuing smokers. First Nations (FN) populations' tobacco use is estimated to be 2-3 times that of other Canadians and, in part, a reflection that tobacco products purchased on reserve by FN people are tax exempt.…
Taxation: Myths and Realities. A Courses by Newspaper Reader.
ERIC Educational Resources Information Center
Break, George F., Ed.; Wallin, Bruce, Ed.
This reader is one of two supplementary materials for a newspaper course about taxation and tax reform. Five units contain 75 primary-source readings about topics such as tax loopholes, social security financing, income tax reform, the impact of taxes on the economy, and alternatives to the property tax. Sources include government publications,…
Property Taxation and the Finance of Education. TRED 7.
ERIC Educational Resources Information Center
Lindholm, Richard W., Ed.
More than twenty experts present their views on the strengths and weaknesses of the property tax system, while comparing it with other possible revenue sources. Together, they develop a comprehensive theory and philosophy of the use of the property tax and land value taxation to finance public education. The contributors give thorough…
Urban Property Taxation: III. Rejection and Reformation. Exchange Bibliography 481.
ERIC Educational Resources Information Center
White, Anthony G.
This is one of three related bibliographies listing publications dealing with the broad topic of property taxation. This particular volume concerns variations on the central theme of reform. Included are sources dealing with redesigning systems, exemptions, judicial review, alternatives, limitations, equalization, differentials, and model laws.…
Taxation and the Preservation of Tribal Political and Geographical Autonomy.
ERIC Educational Resources Information Center
Clow, Richmond L.
1991-01-01
Examines the complexities of the taxation issue in Indian affairs, both for American Indian reservations and adjacent local governments. Demonstrates the role of statutes and case law in the recurring struggle to balance tribal immunities guaranteed by the federal government with the expectations of non-Indian taxpayers. (SV)
Taxation of Fringe Benefits: Alternative Approaches to Current Problems.
ERIC Educational Resources Information Center
Cohen, Anita E.
1979-01-01
The current IRS tax treatment of fringe benefits is seen as inadequate, and the judicial precept confusing, because groups of employee benefits are inappropriately excluded from taxation as perquisites. A tax equalization approach is proposed. Available from Suffolk University Law Review Office, 41 Temple St., Boston, MA 02114. (MSE)
Optimized tapered dipole nanoantenna as efficient energy harvester.
El-Toukhy, Youssef M; Hussein, Mohamed; Hameed, Mohamed Farhat O; Heikal, A M; Abd-Elrazzak, M M; Obayya, S S A
2016-07-11
In this paper, a novel design of tapered dipole nanoantenna is introduced and numerically analyzed for energy harvesting applications. The proposed design consists of three steps tapered dipole nanoantenna with rectangular shape. Full systematic analysis is carried out where the antenna impedance, return loss, harvesting efficiency and field confinement are calculated using 3D finite element frequency domain method (3D-FEFD). The structure geometrical parameters are optimized using particle swarm algorithm (PSO) to improve the harvesting efficiency and reduce the return loss at wavelength of 500 nm. A harvesting efficiency of 55.3% is achieved which is higher than that of conventional dipole counterpart by 29%. This enhancement is attributed to the high field confinement in the dipole gap as a result of multiple tips created in the nanoantenna design. Furthermore, the antenna input impedance is tuned to match a wide range of fabricated diode based upon the multi-resonance characteristic of the proposed structure. PMID:27410898
Human energy - optimal control of disturbance rejection during constrained standing.
Mihelj, M; Munih, M; Ponikvar, M
2003-01-01
An optimal control system that enables a subject to stand without hand support in the sagittal plane was designed. The subject was considered as a double inverted pendulum structure with a voluntarily controlled degree of freedom in the upper trunk and artificially controlled degree of freedom in the ankle joints. The control system design was based on a minimization of cost function that estimated the effort of the ankle joint muscles through observation of the ground reaction force position relative to the ankle joint axis. By maintaining the centre of pressure close to the ankle joint axis the objective of the upright stance is fulfilled with minimal ankle muscle energy cost. The performance of the developed controller was evaluated in a simulation-based study. The results were compared with the responses of an unimpaired subject to different disturbances in the sagittal plane. The proposed cost function was shown to produce a reasonable approximation of human natural behaviour. PMID:12936049
Real options valuation and optimization of energy assets
NASA Astrophysics Data System (ADS)
Thompson, Matthew
In this thesis we present algorithms for the valuation and optimal operation of natural gas storage facilities, hydro-electric power plants and thermal power generators in competitive markets. Real options theory is used to derive nonlinear partial-integro-differential equations (PIDEs) for the valuation and optimal operating strategies of all types of facilities. The equations are designed to incorporate a wide class of spot price models that can exhibit the same time-dependent, mean-reverting dynamics and price spikes as those observed in most energy markets. Particular attention is paid to the operational characteristics of real energy assets. For natural gas storage facilities these characteristics include: working gas capacities, variable deliverability and injection rates and cycling limitations. For thermal power plants relevant operational characteristics include variable start-up times and costs, control response time lags, minimum generating levels, nonlinear output functions, structural limitations on ramp rates, and minimum up/down time restrictions. For hydro-electric units, head effects and environmental constraints are addressed. We illustrate the models with numerical examples of a gas storage facility, a hydro-electric pump storage facility and a thermal power plant. This PIDE framework is the first in the literature to achieve second order accuracy in characterizing the operating states of hydro-electric and hydro-thermal power plants. The continuous state space representation derived in this thesis can therefore achieve far greater realism in terms of operating state specification than any other method in the literature to date. This thesis is also the first and only to allow for any continuous time jump diffusion processes in order to account for price spikes.
Stochastic search, optimization and regression with energy applications
NASA Astrophysics Data System (ADS)
Hannah, Lauren A.
Designing clean energy systems will be an important task over the next few decades. One of the major roadblocks is a lack of mathematical tools to economically evaluate those energy systems. However, solutions to these mathematical problems are also of interest to the operations research and statistical communities in general. This thesis studies three problems that are of interest to the energy community itself or provide support for solution methods: R&D portfolio optimization, nonparametric regression and stochastic search with an observable state variable. First, we consider the one stage R&D portfolio optimization problem to avoid the sequential decision process associated with the multi-stage. The one stage problem is still difficult because of a non-convex, combinatorial decision space and a non-convex objective function. We propose a heuristic solution method that uses marginal project values---which depend on the selected portfolio---to create a linear objective function. In conjunction with the 0-1 decision space, this new problem can be solved as a knapsack linear program. This method scales well to large decision spaces. We also propose an alternate, provably convergent algorithm that does not exploit problem structure. These methods are compared on a solid oxide fuel cell R&D portfolio problem. Next, we propose Dirichlet Process mixtures of Generalized Linear Models (DPGLM), a new method of nonparametric regression that accommodates continuous and categorical inputs, and responses that can be modeled by a generalized linear model. We prove conditions for the asymptotic unbiasedness of the DP-GLM regression mean function estimate. We also give examples for when those conditions hold, including models for compactly supported continuous distributions and a model with continuous covariates and categorical response. We empirically analyze the properties of the DP-GLM and why it provides better results than existing Dirichlet process mixture regression
Applications of Optimal Building Energy System Selection and Operation
Marnay, Chris; Stadler, Michael; Siddiqui, Afzal; DeForest, Nicholas; Donadee, Jon; Bhattacharya, Prajesh; Lai, Judy
2011-04-01
Berkeley Lab has been developing the Distributed Energy Resources Customer Adoption Model (DER-CAM) for several years. Given load curves for energy services requirements in a building microgrid (u grid), fuel costs and other economic inputs, and a menu of available technologies, DER-CAM finds the optimum equipment fleet and its optimum operating schedule using a mixed integer linear programming approach. This capability is being applied using a software as a service (SaaS) model. Optimisation problems are set up on a Berkeley Lab server and clients can execute their jobs as needed, typically daily. The evolution of this approach is demonstrated by description of three ongoing projects. The first is a public access web site focused on solar photovoltaic generation and battery viability at large commercial and industrial customer sites. The second is a building CO2 emissions reduction operations problem for a University of California, Davis student dining hall for which potential investments are also considered. And the third, is both a battery selection problem and a rolling operating schedule problem for a large County Jail. Together these examples show that optimization of building u grid design and operation can be effectively achieved using SaaS.
Hoan, Tran-Nhut-Khai; Hiep, Vu-Van; Koo, In-Soo
2016-01-01
This paper considers cognitive radio networks (CRNs) utilizing multiple time-slotted primary channels in which cognitive users (CUs) are powered by energy harvesters. The CUs are under the consideration that hardware constraints on radio devices only allow them to sense and transmit on one channel at a time. For a scenario where the arrival of harvested energy packets and the battery capacity are finite, we propose a scheme to optimize (i) the channel-sensing schedule (consisting of finding the optimal action (silent or active) and sensing order of channels) and (ii) the optimal transmission energy set corresponding to the channels in the sensing order for the operation of the CU in order to maximize the expected throughput of the CRN over multiple time slots. Frequency-switching delay, energy-switching cost, correlation in spectrum occupancy across time and frequency and errors in spectrum sensing are also considered in this work. The performance of the proposed scheme is evaluated via simulation. The simulation results show that the throughput of the proposed scheme is greatly improved, in comparison to related schemes in the literature. The collision ratio on the primary channels is also investigated. PMID:27043571
Hoan, Tran-Nhut-Khai; Hiep, Vu-Van; Koo, In-Soo
2016-01-01
This paper considers cognitive radio networks (CRNs) utilizing multiple time-slotted primary channels in which cognitive users (CUs) are powered by energy harvesters. The CUs are under the consideration that hardware constraints on radio devices only allow them to sense and transmit on one channel at a time. For a scenario where the arrival of harvested energy packets and the battery capacity are finite, we propose a scheme to optimize (i) the channel-sensing schedule (consisting of finding the optimal action (silent or active) and sensing order of channels) and (ii) the optimal transmission energy set corresponding to the channels in the sensing order for the operation of the CU in order to maximize the expected throughput of the CRN over multiple time slots. Frequency-switching delay, energy-switching cost, correlation in spectrum occupancy across time and frequency and errors in spectrum sensing are also considered in this work. The performance of the proposed scheme is evaluated via simulation. The simulation results show that the throughput of the proposed scheme is greatly improved, in comparison to related schemes in the literature. The collision ratio on the primary channels is also investigated. PMID:27043571
New Perspectives in Thermoelectric Energy Recovery System Design Optimization
Hendricks, Terry J.; Karri, Naveen K.; Hogan, Tim; Cauchy, Charles J.
2013-02-12
Abstract: Large amounts of waste heat are generated worldwide in industrial processes, automotive transportation, diesel engine exhaust, military generators, and incinerators because 60-70% of the fuel energy is typically lost in these processes. There is a strong need to develop technologies that recover this waste heat to increase fuel efficiency and minimize fuel requirements in these industrial processes, automotive and heavy vehicle engines, diesel generators, and incinerators. There are additional requirements to reduce CO2 production and environmental footprints in many of these applications. Recent work with the Strategic Environmental Research and Development Program office has investigated new thermoelectric (TE) materials and systems that can operate at higher performance levels and show a viable pathway to lightweight, small form-factor, advanced thermoelectric generator (TEG) systems to recover waste heat in many of these applications. New TE materials include nano-composite materials such as lead-antimony-silver-telluride (LAST) and lead-antimony-silver-tin-telluride (LASTT) compounds. These new materials have created opportunities for high-performance, segmented-element TE devices. New higher-performance TE devices segmenting LAST/LASTT materials with bismuth telluride have been designed and fabricated. Sectioned TEG systems using these new TE devices and materials have been designed. Integrated heat exchanger/TE device system analyses of sectioned TE system designs have been performed creating unique efficiency-power maps that provide better understandings and comparisons of design tradeoffs and nominal and off-nominal system performance conditions. New design perspectives in optimization of sectioned TE design approaches are discussed that provide insight on how to optimize such sectioned TE systems. System performance analyses using ANSYS® TE modeling capabilities have integrated heat exchanger performance models with ANSYS® TE models to extend
Starship Sails Propelled by Cost-Optimized Directed Energy
NASA Astrophysics Data System (ADS)
Benford, J.
Microwave and laser-propelled sails are a new class of spacecraft using photon acceleration. It is the only method of interstellar flight that has no physics issues. Laboratory demonstrations of basic features of beam-driven propulsion, flight, stability (`beam-riding'), and induced spin, have been completed in the last decade, primarily in the microwave. It offers much lower cost probes after a substantial investment in the launcher. Engineering issues are being addressed by other applications: fusion (microwave, millimeter and laser sources) and astronomy (large aperture antennas). There are many candidate sail materials: carbon nanotubes and microtrusses, beryllium, graphene, etc. For acceleration of a sail, what is the cost-optimum high power system? Here the cost is used to constrain design parameters to estimate system power, aperture and elements of capital and operating cost. From general relations for cost-optimal transmitter aperture and power, system cost scales with kinetic energy and inversely with sail diameter and frequency. So optimal sails will be larger, lower in mass and driven by higher frequency beams. Estimated costs include economies of scale. We present several starship point concepts. Systems based on microwave, millimeter wave and laser technologies are of equal cost at today's costs. The frequency advantage of lasers is cancelled by the high cost of both the laser and the radiating optic. Cost of interstellar sailships is very high, driven by current costs for radiation source, antennas and especially electrical power. The high speeds necessary for fast interstellar missions make the operating cost exceed the capital cost. Such sailcraft will not be flown until the cost of electrical power in space is reduced orders of magnitude below current levels.
Modeling and optimization of energy storage system for microgrid
NASA Astrophysics Data System (ADS)
Qiu, Xin
The vanadium redox flow battery (VRB) is well suited for the applications of microgrid and renewable energy. This thesis will have a practical analysis of the battery itself and its application in microgrid systems. The first paper analyzes the VRB use in a microgrid system. The first part of the paper develops a reduced order circuit model of the VRB and analyzes its experimental performance efficiency during deployment. The statistical methods and neural network approximation are used to estimate the system parameters. The second part of the paper addresses the implementation issues of the VRB application in a photovoltaic-based microgrid system. A new dc-dc converter was proposed to provide improved charging performance. The paper was published on IEEE Transactions on Smart Grid, Vol. 5, No. 4, July 2014. The second paper studies VRB use within a microgrid system from a practical perspective. A reduced order circuit model of the VRB is introduced that includes the losses from the balance of plant including system and environmental controls. The proposed model includes the circulation pumps and the HVAC system that regulates the environment of the VRB enclosure. In this paper, the VRB model is extended to include the ESS environmental controls to provide a model that provides a more realistic efficiency profile. The paper was submitted to IEEE Transactions on Sustainable Energy. Third paper discussed the optimal control strategy when VRB works with other type of battery in a microgird system. The work in first paper is extended. A high level control strategy is developed to coordinate a lead acid battery and a VRB with reinforcement learning. The paper is to be submitted to IEEE Transactions on Smart Grid.
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.
Yang, Chao; Meza, Juan C.; Wang, Lin-Wang
2005-07-26
A new direct constrained optimization algorithm forminimizing the Kohn-Sham (KS) total energy functional is presented inthis paper. The key ingredients of this algorithm involve projecting thetotal energy functional into a sequences of subspaces of small dimensionsand seeking the minimizer of total energy functional within eachsubspace. The minimizer of a subspace energy functional not only providesa search direction along which the KS total energy functional decreasesbut also gives an optimal "step-length" to move along this searchdirection. A numerical example is provided to demonstrate that this newdirect constrained optimization algorithm can be more efficient than theself-consistent field (SCF) iteration.
Economic aspects of tobacco use and taxation policy.
Godfrey, C.; Maynard, A.
1988-01-01
Tax levels have important effects on cigarette prices and tax revenues. Over 70p of every pound spent on tobacco goes to the Chancellor of the Exchequer, yielding over 5 billion pounds. But the value of tobacco tax revenues have generally fallen--by 1986 they were 10% lower than at their peak in 1965, and tobacco revenue is becoming a smaller proportion of total tax receipts. The impact of a consistent increase in tobacco taxation is important in terms of reduced consumption (and harm to health) as well as in terms of reduced employment. Revenue may, however, increase in the short term. Finally, if the findings of Townsend and Atkinson et al (see above) still apply then the distributive effects of increased taxation on the poor might be less than is sometimes feared. PMID:3416168
Optimal Wind Energy Integration in Large-Scale Electric Grids
NASA Astrophysics Data System (ADS)
Albaijat, Mohammad H.
The major concern in electric grid operation is operating under the most economical and reliable fashion to ensure affordability and continuity of electricity supply. This dissertation investigates the effects of such challenges, which affect electric grid reliability and economic operations. These challenges are: 1. Congestion of transmission lines, 2. Transmission lines expansion, 3. Large-scale wind energy integration, and 4. Phaser Measurement Units (PMUs) optimal placement for highest electric grid observability. Performing congestion analysis aids in evaluating the required increase of transmission line capacity in electric grids. However, it is necessary to evaluate expansion of transmission line capacity on methods to ensure optimal electric grid operation. Therefore, the expansion of transmission line capacity must enable grid operators to provide low-cost electricity while maintaining reliable operation of the electric grid. Because congestion affects the reliability of delivering power and increases its cost, the congestion analysis in electric grid networks is an important subject. Consequently, next-generation electric grids require novel methodologies for studying and managing congestion in electric grids. We suggest a novel method of long-term congestion management in large-scale electric grids. Owing to the complication and size of transmission line systems and the competitive nature of current grid operation, it is important for electric grid operators to determine how many transmission lines capacity to add. Traditional questions requiring answers are "Where" to add, "How much of transmission line capacity" to add, and "Which voltage level". Because of electric grid deregulation, transmission lines expansion is more complicated as it is now open to investors, whose main interest is to generate revenue, to build new transmission lines. Adding a new transmission capacity will help the system to relieve the transmission system congestion, create
Investigation of Cost and Energy Optimization of Drinking Water Distribution Systems.
Cherchi, Carla; Badruzzaman, Mohammad; Gordon, Matthew; Bunn, Simon; Jacangelo, Joseph G
2015-11-17
Holistic management of water and energy resources through energy and water quality management systems (EWQMSs) have traditionally aimed at energy cost reduction with limited or no emphasis on energy efficiency or greenhouse gas minimization. This study expanded the existing EWQMS framework and determined the impact of different management strategies for energy cost and energy consumption (e.g., carbon footprint) reduction on system performance at two drinking water utilities in California (United States). The results showed that optimizing for cost led to cost reductions of 4% (Utility B, summer) to 48% (Utility A, winter). The energy optimization strategy was successfully able to find the lowest energy use operation and achieved energy usage reductions of 3% (Utility B, summer) to 10% (Utility A, winter). The findings of this study revealed that there may be a trade-off between cost optimization (dollars) and energy use (kilowatt-hours), particularly in the summer, when optimizing the system for the reduction of energy use to a minimum incurred cost increases of 64% and 184% compared with the cost optimization scenario. Water age simulations through hydraulic modeling did not reveal any adverse effects on the water quality in the distribution system or in tanks from pump schedule optimization targeting either cost or energy minimization. PMID:26461069
Reduction of Systemic Risk by Means of Pigouvian Taxation.
Zlatić, Vinko; Gabbi, Giampaolo; Abraham, Hrvoje
2015-01-01
We analyze the possibility of reduction of systemic risk in financial markets through Pigouvian taxation of financial institutions, which is used to support the rescue fund. We introduce the concept of the cascade risk with a clear operational definition as a subclass and a network related measure of the systemic risk. Using financial networks constructed from real Italian money market data and using realistic parameters, we show that the cascade risk can be substantially reduced by a small rate of taxation and by means of a simple strategy of the money transfer from the rescue fund to interbanking market subjects. Furthermore, we show that while negative effects on the return on investment (ROI) are direct and certain, an overall positive effect on risk adjusted return on investments (ROIRA) is visible. Please note that the taxation is introduced as a monetary/regulatory, not as a _scal measure, as the term could suggest. The rescue fund is implemented in a form of a common reserve fund. PMID:26177351
Reduction of Systemic Risk by Means of Pigouvian Taxation
Zlatić, Vinko; Gabbi, Giampaolo; Abraham, Hrvoje
2015-01-01
We analyze the possibility of reduction of systemic risk in financial markets through Pigouvian taxation of financial institutions, which is used to support the rescue fund. We introduce the concept of the cascade risk with a clear operational definition as a subclass and a network related measure of the systemic risk. Using financial networks constructed from real Italian money market data and using realistic parameters, we show that the cascade risk can be substantially reduced by a small rate of taxation and by means of a simple strategy of the money transfer from the rescue fund to interbanking market subjects. Furthermore, we show that while negative effects on the return on investment (ROI) are direct and certain, an overall positive effect on risk adjusted return on investments (ROIRA) is visible. Please note that the taxation is introduced as a monetary/regulatory, not as a _scal measure, as the term could suggest. The rescue fund is implemented in a form of a common reserve fund. PMID:26177351
Towards a coherent European approach for taxation of combustible waste.
Dubois, Maarten
2013-08-01
Although intra-European trade of combustible waste has grown strongly in the last decade, incineration and landfill taxes remain disparate within Europe. The paper proposes a more coherent taxation approach for Europe that is based on the principle of Pigovian taxation, i.e. the internalization of environmental damage costs. The approach aims to create a level playing field between European regions while reinforcing incentives for sustainable management of combustible waste. Three important policy recommendations emerge. First, integrating waste incineration into the European Emissions Trading System for greenhouse gases (EU ETS) reduces the risk of tax competition between regions. Second, because taxation of every single air pollutant from waste incineration is cumbersome, a differentiated waste incineration tax based on NO(x) emissions can serve as a second-best instrument. Finally, in order to strengthen incentives for ash treatment, a landfill tax should apply for landfilled incineration residues. An example illustrates the coherence of the policy recommendations for incineration technologies with diverse environmental effects. PMID:23602303
Towards a coherent European approach for taxation of combustible waste
Dubois, Maarten
2013-08-15
Highlights: • Current European waste taxes do not constitute a level playing field. • Integrating waste incineration in EU ETS avoids regional tax competition. • A differentiated incineration tax is a second-best instrument for NO{sub x} emissions. • A tax on landfilled incineration residues stimulates ash treatment. - Abstract: Although intra-European trade of combustible waste has grown strongly in the last decade, incineration and landfill taxes remain disparate within Europe. The paper proposes a more coherent taxation approach for Europe that is based on the principle of Pigovian taxation, i.e. the internalization of environmental damage costs. The approach aims to create a level playing field between European regions while reinforcing incentives for sustainable management of combustible waste. Three important policy recommendations emerge. First, integrating waste incineration into the European Emissions Trading System for greenhouse gases (EU ETS) reduces the risk of tax competition between regions. Second, because taxation of every single air pollutant from waste incineration is cumbersome, a differentiated waste incineration tax based on NO{sub x} emissions can serve as a second-best instrument. Finally, in order to strengthen incentives for ash treatment, a landfill tax should apply for landfilled incineration residues. An example illustrates the coherence of the policy recommendations for incineration technologies with diverse environmental effects.
Tsvetkov, Pavel Valeryevich; Rodriguez, Salvador B.; Ames, David E., II; Rochau, Gary Eugene
2009-09-01
The impact associated with energy generation and utilization is immeasurable due to the immense, widespread, and myriad effects it has on the world and its inhabitants. The polar extremes are demonstrated on the one hand, by the high quality of life enjoyed by individuals with access to abundant reliable energy sources, and on the other hand by the global-scale environmental degradation attributed to the affects of energy production and use. Thus, nations strive to increase their energy generation, but are faced with the challenge of doing so with a minimal impact on the environment and in a manner that is self-reliant. Consequently, a revival of interest in nuclear energy has followed, with much focus placed on technologies for transmuting nuclear spent fuel. The performed research investigates nuclear energy systems that optimize the destruction of nuclear waste. In the context of this effort, nuclear energy system is defined as a configuration of nuclear reactors and corresponding fuel cycle components. The proposed system has unique characteristics that set it apart from other systems. Most notably the dedicated High-Energy External Source Transmuter (HEST), which is envisioned as an advanced incinerator used in combination with thermal reactors. The system is configured for examining environmentally benign fuel cycle options by focusing on minimization or elimination of high level waste inventories. Detailed high-fidelity exact-geometry models were developed for representative reactor configurations. They were used in preliminary calculations with Monte Carlo N-Particle eXtented (MCNPX) and Standardized Computer Analysis for Licensing Evaluation (SCALE) code systems. The reactor models have been benchmarked against existing experimental data and design data. Simulink{reg_sign}, an extension of MATLAB{reg_sign}, is envisioned as the interface environment for constructing the nuclear energy system model by linking the individual reactor and fuel component sub
Zitney, S.E.
2007-06-01
Emerging fossil energy power generation systems must operate with unprecedented efficiency and near-zero emissions, while optimizing profitably amid cost fluctuations for raw materials, finished products, and energy. To help address these challenges, the fossil energy industry will have to rely increasingly on the use advanced computational tools for modeling and simulating complex process systems. In this paper, we present the computational research challenges and opportunities for the optimization of fossil energy power generation systems across the plant lifecycle from process synthesis and design to plant operations. We also look beyond the plant gates to discuss research challenges and opportunities for enterprise-wide optimization, including planning, scheduling, and supply chain technologies.
Optimization of Electrical Energy Production by using Modified Differential Evolution Algorithm
NASA Astrophysics Data System (ADS)
Glotic, Arnel
The dissertation addressed the optimization of electrical energy production from hydro power plants and thermal power plants. It refers to short-term optimization and presents a complex optimization problem. The complexity of the problem arises from an extensive number of co-dependent variables and power plant constraints. According to the complexity of the problem, the differential evolution algorithm known as the successful and robust optimization algorithm was selected as an appropriate algorithm for optimization. The performance of this differential evolution algorithm is closely connected with a control parameters' set and its capabilities being inter alia improved by the algorithm's parallelization. The capabilities of achieving a global optimal solution within the optimization of electrical energy production are improved by the proposed modified differential evolution algorithm with new parallelization mode. This algorithm's performance is also improved by its proposed dynamic population size throughout the optimization process. In addition to achieving better optimization results in comparison with the classic differential evolution algorithm, the proposed dynamic population size reduces convergence time. The improvements of this algorithm presented in the dissertation, besides power plant models mostly used in scientific publications, were also tested on the power plant models represented by real parameters'. The optimization of electrical energy from hydro and thermal power plants is followed by certain criteria; satisfying system demand, minimizing usage of water quantity per produced electrical energy unit, minimizing or eliminating water spillage, satisfying the final reservoir states of hydro power plants and minimizing fuel costs and emissions of thermal power plants.
Energy optimization of driving amplifiers for smart actuators
NASA Astrophysics Data System (ADS)
Zhu, Huiyu; Song, Chunping; Lindner, Douglas K.; Abdalla, Mostafa M.; Gurdal, Zafer
2003-07-01
A high-efficiency driving amplifier with small profile for smart actuators is essential for portable actuator devices. In this paper, a detailed optimized design of half-bridge switching circuit to drive smart actuators is described. The mathematical optimization procedure is applied to the traditional circuit design to make the circuit smaller and more efficient. The objecitve function presented in this paper is to minimize the total weight of the circuit, including heat sink, inductor and bus capacitor. The calculation of the power dissipation of MOSFET is adopted as a critical step to get the suitable heat sink. The optimization results are presented to demonstrate the effectiveness of this method.
NASA Astrophysics Data System (ADS)
Cai, Qiong; Adjiman, Claire S.; Brandon, Nigel P.
2014-12-01
The penetration of intermittent renewable energies requires the development of energy storage technologies. High temperature electrolysis using solid oxide electrolyser cells (SOECs) as a potential energy storage technology, provides the prospect of a cost-effective and energy efficient route to clean hydrogen production. The development of optimal control strategies when SOEC systems are coupled with intermittent renewable energies is discussed. Hydrogen production is examined in relation to energy consumption. Control strategies considered include maximizing hydrogen production, minimizing SOEC energy consumption and minimizing compressor energy consumption. Optimal control trajectories of the operating variables over a given period of time show feasible control for the chosen situations. Temperature control of the SOEC stack is ensured via constraints on the overall temperature difference across the cell and the local temperature gradient within the SOEC stack, to link materials properties with system performance; these constraints are successfully managed. The relative merits of the optimal control strategies are analyzed.
Code of Federal Regulations, 2010 CFR
2010-04-01
... exemption from taxation apply to affordable housing activities? 1000.242 Section 1000.242 Housing and Urban... ACTIVITIES Indian Housing Plan (IHP) § 1000.242 When does the requirement for exemption from taxation apply to affordable housing activities? The requirement for exemption from taxation applies only to...
20 CFR 638.812 - State and local taxation of Job Corps deliverers.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 20 Employees' Benefits 3 2012-04-01 2012-04-01 false State and local taxation of Job Corps... LABOR JOB CORPS PROGRAM UNDER TITLE IV-B OF THE JOB TRAINING PARTNERSHIP ACT Administrative Provisions § 638.812 State and local taxation of Job Corps deliverers. The Act provides that transactions...
20 CFR 638.812 - State and local taxation of Job Corps deliverers.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false State and local taxation of Job Corps... LABOR JOB CORPS PROGRAM UNDER TITLE IV-B OF THE JOB TRAINING PARTNERSHIP ACT Administrative Provisions § 638.812 State and local taxation of Job Corps deliverers. The Act provides that transactions...
26 CFR 1.857-1 - Taxation of real estate investment trusts.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 9 2011-04-01 2011-04-01 false Taxation of real estate investment trusts. 1.857...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-1 Taxation of real... real estate investment trust for a taxable year unless— (1) The deduction for dividends paid for...
26 CFR 1.857-1 - Taxation of real estate investment trusts.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 9 2013-04-01 2013-04-01 false Taxation of real estate investment trusts. 1.857...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-1 Taxation of real... real estate investment trust for a taxable year unless— (1) The deduction for dividends paid for...
26 CFR 1.857-1 - Taxation of real estate investment trusts.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 9 2014-04-01 2014-04-01 false Taxation of real estate investment trusts. 1.857...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-1 Taxation of real... real estate investment trust for a taxable year unless— (1) The deduction for dividends paid for...
26 CFR 1.857-1 - Taxation of real estate investment trusts.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 9 2012-04-01 2012-04-01 false Taxation of real estate investment trusts. 1.857...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-1 Taxation of real... real estate investment trust for a taxable year unless— (1) The deduction for dividends paid for...
26 CFR 1.991-1 - Taxation of a domestic international sales corporation.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 10 2012-04-01 2012-04-01 false Taxation of a domestic international sales... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Domestic International Sales Corporations § 1.991-1 Taxation of a domestic international sales corporation. (a) In general. A corporation which is...
26 CFR 1.991-1 - Taxation of a domestic international sales corporation.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 10 2013-04-01 2013-04-01 false Taxation of a domestic international sales... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Domestic International Sales Corporations § 1.991-1 Taxation of a domestic international sales corporation. (a) In general. A corporation which is...
26 CFR 1.991-1 - Taxation of a domestic international sales corporation.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 10 2011-04-01 2011-04-01 false Taxation of a domestic international sales... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Domestic International Sales Corporations § 1.991-1 Taxation of a domestic international sales corporation. (a) In general. A corporation which is...
26 CFR 1.991-1 - Taxation of a domestic international sales corporation.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 10 2014-04-01 2013-04-01 true Taxation of a domestic international sales... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Domestic International Sales Corporations § 1.991-1 Taxation of a domestic international sales corporation. (a) In general. A corporation which is...
26 CFR 1.522-2 - Manner of taxation of cooperative associations subject to section 522.
Code of Federal Regulations, 2010 CFR
2010-04-01
... provided in 26 CFR (1939) 39.22(d)-3 (Regulations 118) must exercise the election provided in section 472... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Manner of taxation of cooperative associations...-2 Manner of taxation of cooperative associations subject to section 522. (a) In general....
ERIC Educational Resources Information Center
Stein, Todd J.
1990-01-01
The most common problems associated with establishing educational programs abroad are illustrated by the case of Britain, which has a large population of foreign students. Four problem areas are addressed (program formation, immigration, accreditation, and taxation), with the greatest amount of attention given to taxation. (MSE)
26 CFR 1.991-1 - Taxation of a domestic international sales corporation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 10 2010-04-01 2010-04-01 false Taxation of a domestic international sales... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Domestic International Sales Corporations § 1.991-1 Taxation of a domestic international sales corporation. (a) In general. A corporation which is a DISC for...
26 CFR 1.857-6 - Method of taxation of shareholders of real estate investment trusts.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Method of taxation of shareholders of real estate investment trusts. 1.857-6 Section 1.857-6 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT...-6 Method of taxation of shareholders of real estate investment trusts. (a) Ordinary income....
26 CFR 1.1293-1 - Current taxation of income from qualified electing funds.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Current taxation of income from qualified electing funds. 1.1293-1 Section 1.1293-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Losses § 1.1293-1 Current taxation of income from qualified electing funds. (a) In general. (1)...
20 CFR 209.14 - Report of separation allowances subject to tier II taxation.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Report of separation allowances subject to tier II taxation. 209.14 Section 209.14 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER... separation allowances subject to tier II taxation. For any employee who is paid a separation payment,...
26 CFR 1.597-2 - Taxation of Federal financial assistance.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Taxation of Federal financial assistance. 1.597-2 Section 1.597-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Mutual Savings Banks, Etc. § 1.597-2 Taxation of...
48 CFR 229.170 - Reporting of foreign taxation on U.S. assistance programs.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Reporting of foreign taxation on U.S. assistance programs. 229.170 Section 229.170 Federal Acquisition Regulations System... General 229.170 Reporting of foreign taxation on U.S. assistance programs....
26 CFR 1.857-1 - Taxation of real estate investment trusts.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Taxation of real estate investment trusts. 1.857-1 Section 1.857-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Real Estate Investment Trusts § 1.857-1 Taxation of real...
26 CFR 1.457-7 - Taxation of Distributions Under Eligible Plans.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Taxation of Distributions Under Eligible Plans. 1.457-7 Section 1.457-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY...-7 Taxation of Distributions Under Eligible Plans. (a) General rules for when amounts are included...
26 CFR 1.852-1 - Taxation of regulated investment companies.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Taxation of regulated investment companies. 1.852-1 Section 1.852-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED....852-1 Taxation of regulated investment companies. (a) Requirements applicable thereto—(1) In...
26 CFR 1.852-4 - Method of taxation of shareholders of regulated investment companies.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Method of taxation of shareholders of regulated investment companies. 1.852-4 Section 1.852-4 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE... Investment Trusts § 1.852-4 Method of taxation of shareholders of regulated investment companies....
26 CFR 1.860C-1 - Taxation of holders of residual interests.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Taxation of holders of residual interests. 1.860C-1 Section 1.860C-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Real Estate Investment Trusts § 1.860C-1 Taxation of...
26 CFR 1.852-1 - Taxation of regulated investment companies.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 9 2012-04-01 2012-04-01 false Taxation of regulated investment companies. 1...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Regulated Investment Companies and Real Estate Investment Trusts § 1.852-1 Taxation of regulated investment companies. (a) Requirements applicable thereto—(1)...
U.S. Taxation of Business: Relevance of the European Experience. German Studies Notes.
ERIC Educational Resources Information Center
McLure, Charles E., Jr.
American and European business taxation policies are compared in this booklet. Topics discussed in the paper include effects of the corporation income tax, integration of income taxation, and the value added tax. Two major differences between the American and European systems are noted. First, European countries derive substantial portions of…
Optimal planning and design of a renewable energy based supply system for microgrids
Hafez, Omar; Bhattacharya, Kankar
2012-03-03
This paper presents a technique for optimal planning and design of hybrid renewable energy systems for microgrid applications. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is used to determine the optimal size and type of distributed energy resources (DERs) and their operating schedules for a sample utility distribution system. Using the DER-CAM results, an evaluation is performed to evaluate the electrical performance of the distribution circuit if the DERs selected by the DER-CAM optimization analyses are incorporated. Results of analyses regarding the economic benefits of utilizing the optimal locations identified for the selected DER within the system are alsomore » presented. The actual Brookhaven National Laboratory (BNL) campus electrical network is used as an example to show the effectiveness of this approach. The results show that these technical and economic analyses of hybrid renewable energy systems are essential for the efficient utilization of renewable energy resources for microgird applications.« less
Optimal planning and design of a renewable energy based supply system for microgrids
Hafez, Omar; Bhattacharya, Kankar
2012-03-03
This paper presents a technique for optimal planning and design of hybrid renewable energy systems for microgrid applications. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is used to determine the optimal size and type of distributed energy resources (DERs) and their operating schedules for a sample utility distribution system. Using the DER-CAM results, an evaluation is performed to evaluate the electrical performance of the distribution circuit if the DERs selected by the DER-CAM optimization analyses are incorporated. Results of analyses regarding the economic benefits of utilizing the optimal locations identified for the selected DER within the system are also presented. The actual Brookhaven National Laboratory (BNL) campus electrical network is used as an example to show the effectiveness of this approach. The results show that these technical and economic analyses of hybrid renewable energy systems are essential for the efficient utilization of renewable energy resources for microgird applications.
STATE TAXATION OF MINERAL DEPOSITS AND PRODUCTION
Development of energy resources in the more rural western states is likely to create severe financial problems for some state and local governments. This new economic activity, with population in-migration and greater demand for public services, will generate a need for more gove...
NASA Astrophysics Data System (ADS)
Huang, Bo; Hsieh, Chen-Yu; Golnaraghi, Farid; Moallem, Mehrdad
2015-11-01
In this paper a vehicle suspension system with energy harvesting capability is developed, and an analytical methodology for the optimal design of the system is proposed. The optimization technique provides design guidelines for determining the stiffness and damping coefficients aimed at the optimal performance in terms of ride comfort and energy regeneration. The corresponding performance metrics are selected as root-mean-square (RMS) of sprung mass acceleration and expectation of generated power. The actual road roughness is considered as the stochastic excitation defined by ISO 8608:1995 standard road profiles and used in deriving the optimization method. An electronic circuit is proposed to provide variable damping in the real-time based on the optimization rule. A test-bed is utilized and the experiments under different driving conditions are conducted to verify the effectiveness of the proposed method. The test results suggest that the analytical approach is credible in determining the optimality of system performance.
Wehmeyer, Christoph; Falk von Rudorff, Guido; Wolf, Sebastian; Kabbe, Gabriel; Schärf, Daniel; Kühne, Thomas D; Sebastiani, Daniel
2012-11-21
We present a stochastic, swarm intelligence-based optimization algorithm for the prediction of global minima on potential energy surfaces of molecular cluster structures. Our optimization approach is a modification of the artificial bee colony (ABC) algorithm which is inspired by the foraging behavior of honey bees. We apply our modified ABC algorithm to the problem of global geometry optimization of molecular cluster structures and show its performance for clusters with 2-57 particles and different interatomic interaction potentials. PMID:23181297
NASA Astrophysics Data System (ADS)
Wehmeyer, Christoph; Falk von Rudorff, Guido; Wolf, Sebastian; Kabbe, Gabriel; Schärf, Daniel; Kühne, Thomas D.; Sebastiani, Daniel
2012-11-01
We present a stochastic, swarm intelligence-based optimization algorithm for the prediction of global minima on potential energy surfaces of molecular cluster structures. Our optimization approach is a modification of the artificial bee colony (ABC) algorithm which is inspired by the foraging behavior of honey bees. We apply our modified ABC algorithm to the problem of global geometry optimization of molecular cluster structures and show its performance for clusters with 2-57 particles and different interatomic interaction potentials.
Optimizing Resource and Energy Recovery for Municipal Solid Waste Management
Significant reductions of carbon emissions and air quality impacts can be achieved by optimizing municipal solid waste (MSW) as a resource. Materials and discards management were found to contribute ~40% of overall U.S. GHG emissions as a result of materials extraction, transpo...
Fan System Optimization Improves Production and Saves Energy at Ash Grove Cement Plant
2002-05-01
This case study describes an optimization project implemented on a fan system at Ash Grove Cement Company, which led to annual energy and maintenance savings of $16,000 and 175,000 kilowatt-hours (kWh).
Fan System Optimization Improves Ventilation and Saves Energy at a Computer Chip Manufacturer
2002-01-01
This case study describes an optimization project implemented on a fan system at Ash Grove Cement Company, which led to annual energy and maintenance savings of $16,000 and 175,000 kilowatt-hours (kWh).
Energy and Propulsion Optimization of Solid-Propellant Grain of a Hybrid Power Device
NASA Astrophysics Data System (ADS)
Bondarchuk, Sergey S.; Bondarchuk, Iliya S.; Borisov, Boris V.; Zhukov, Alexandr S.
2016-02-01
A method of distribution of an additional solid-phase component (oxidizer) providing uniformity of grain burning for the purpose of evaluation and optimization of energy and propulsion parameters of hybrid solid-propellant motor is proposed in the paper.
Optimizing Irregular Applications for Energy and Performance on the Tilera Many-core Architecture
Chavarría-Miranda, Daniel; Panyala, Ajay R.; Halappanavar, Mahantesh; Manzano Franco, Joseph B.; Tumeo, Antonino
2015-05-20
Optimizing applications simultaneously for energy and performance is a complex problem. High performance, parallel, irregular applications are notoriously hard to optimize due to their data-dependent memory accesses, lack of structured locality and complex data structures and code patterns. Irregular kernels are growing in importance in applications such as machine learning, graph analytics and combinatorial scientific computing. Performance- and energy-efficient implementation of these kernels on modern, energy efficient, multicore and many-core platforms is therefore an important and challenging problem. We present results from optimizing two irregular applications { the Louvain method for community detection (Grappolo), and high-performance conjugate gradient (HPCCG) { on the Tilera many-core system. We have significantly extended MIT's OpenTuner auto-tuning framework to conduct a detailed study of platform-independent and platform-specific optimizations to improve performance as well as reduce total energy consumption. We explore the optimization design space along three dimensions: memory layout schemes, compiler-based code transformations, and optimization of parallel loop schedules. Using auto-tuning, we demonstrate whole node energy savings of up to 41% relative to a baseline instantiation, and up to 31% relative to manually optimized variants.
Question 7: Optimized Energy Consumption for Protein Synthesis
NASA Astrophysics Data System (ADS)
Szaflarski, Witold; Nierhaus, Knud H.
2007-10-01
In our previous contribution (Nierhaus, Orig Life Evol Biosph, this volume, 2007) we mentioned that life had solved the problem of energy supply in three major steps, and that these steps also mark major stages during the development of life. We further outlined a possible scenario concerning a minimal translational apparatus focusing on the essential components necessary for protein synthesis. Here we continue that consideration by addressing on one of the main problems of early life, namely avoiding wasteful energy loss. With regard to the limiting energy supply of early living systems, i.e. those of say more than 3,000 Ma, a carefully controlled and product oriented energy consumption was in demand. In recent years we learned how a bacterial cell avoids energy drain, thus being able to pump most of the energy into protein synthesis. These lessons must be followed by the design of a minimal living system, which is surveyed in this short article.
Tsvetkov, Pavel Valeryevich; Rodriguez, Salvador B.; Ames, David E., II; Rochau, Gary Eugene
2010-10-01
A new high-fidelity integrated system method and analysis approach was developed and implemented for consistent and comprehensive evaluations of advanced fuel cycles leading to minimized Transuranic (TRU) inventories. The method has been implemented in a developed code system integrating capabilities of Monte Carlo N - Particle Extended (MCNPX) for high-fidelity fuel cycle component simulations. In this report, a Nuclear Energy System (NES) configuration was developed to take advantage of used fuel recycling and transmutation capabilities in waste management scenarios leading to minimized TRU waste inventories, long-term activities, and radiotoxicities. The reactor systems and fuel cycle components that make up the NES were selected for their ability to perform in tandem to produce clean, safe, and dependable energy in an environmentally conscious manner. The diversity in performance and spectral characteristics were used to enhance TRU waste elimination while efficiently utilizing uranium resources and providing an abundant energy source. A computational modeling approach was developed for integrating the individual models of the NES. A general approach was utilized allowing for the Integrated System Model (ISM) to be modified in order to provide simulation for other systems with similar attributes. By utilizing this approach, the ISM is capable of performing system evaluations under many different design parameter options. Additionally, the predictive capabilities of the ISM and its computational time efficiency allow for system sensitivity/uncertainty analysis and the implementation of optimization techniques.
Optimal control, investment and utilization schemes for energy storage under uncertainty
NASA Astrophysics Data System (ADS)
Mirhosseini, Niloufar Sadat
Energy storage has the potential to offer new means for added flexibility on the electricity systems. This flexibility can be used in a number of ways, including adding value towards asset management, power quality and reliability, integration of renewable resources and energy bill savings for the end users. However, uncertainty about system states and volatility in system dynamics can complicate the question of when to invest in energy storage and how best to manage and utilize it. This work proposes models to address different problems associated with energy storage within a microgrid, including optimal control, investment, and utilization. Electric load, renewable resources output, storage technology cost and electricity day-ahead and spot prices are the factors that bring uncertainty to the problem. A number of analytical methodologies have been adopted to develop the aforementioned models. Model Predictive Control and discretized dynamic programming, along with a new decomposition algorithm are used to develop optimal control schemes for energy storage for two different levels of renewable penetration. Real option theory and Monte Carlo simulation, coupled with an optimal control approach, are used to obtain optimal incremental investment decisions, considering multiple sources of uncertainty. Two stage stochastic programming is used to develop a novel and holistic methodology, including utilization of energy storage within a microgrid, in order to optimally interact with energy market. Energy storage can contribute in terms of value generation and risk reduction for the microgrid. The integration of the models developed here are the basis for a framework which extends from long term investments in storage capacity to short term operational control (charge/discharge) of storage within a microgrid. In particular, the following practical goals are achieved: (i) optimal investment on storage capacity over time to maximize savings during normal and emergency
Program document for Energy Systems Optimization Program 2 (ESOP2). Volume 1: Engineering manual
NASA Technical Reports Server (NTRS)
Hamil, R. G.; Ferden, S. L.
1977-01-01
The Energy Systems Optimization Program, which is used to provide analyses of Modular Integrated Utility Systems (MIUS), is discussed. Modifications to the input format to allow modular inputs in specified blocks of data are described. An optimization feature which enables the program to search automatically for the minimum value of one parameter while varying the value of other parameters is reported. New program option flags for prime mover analyses and solar energy for space heating and domestic hot water are also covered.
Analysis of energy saving ability in dimming VLC systems using LEDs with optimized SAHP
NASA Astrophysics Data System (ADS)
Li, Fang; Wu, Kan; Zou, Weiwen; Chen, Jianping
2016-02-01
In this paper, we investigate the energy saving capability of dimming visible light communication (VLC) systems employing SC-4 PPM modulation scheme. We design different optimizations to maximize the energy efficiency according to the different illuminance efficiency with respect to LED's semi-angle at half power (SAHP) for four different LED alignments. Tradeoff between energy efficiency and signal-to-noise ratio (SNR) uniformity are also investigated to achieve better overall performance. The results show that more than 40% energy can be saved over the existing dimmed VLC system employing SC-4 PPM modulation scheme when optimized SAHP LEDs are used.
Community Design for Optimal Energy and Resource Utilization.
ERIC Educational Resources Information Center
Bilenky, Stephen; And Others
Presented is a study which investigated the energy and resource dynamics of a semi-autonomous domestic system for 30 people. The investigation is organized on three levels: (1) developing a preliminary design and design parameters; (2) development and quantification of the energy and resource dynamics; and (3) designing a model to extrapolate…
Optimized Switch Allocation to Improve the Restoration Energy in Distribution Systems
NASA Astrophysics Data System (ADS)
Dezaki, Hamed H.; Abyaneh, Hossein A.; Agheli, Ali; Mazlumi, Kazem
2012-01-01
In distribution networks switching devices play critical role in energy restoration and improving reliability indices. This paper presents a novel objective function to optimally allocate switches in electric power distribution systems. Identifying the optimized location of the switches is a nonlinear programming problem (NLP). In the proposed objective function a new auxiliary function is used to simplify the calculation of the objective function. The output of the auxiliary function is binary. The genetic algorithm (GA) optimization method is used to solve this optimization problem. The proposed method is applied to a real distribution network and the results reveal that the method is successful.
Optimal Combination of Distributed Energy System in an Eco-Campusof Japan
Yang, Yongwen; Gao, Weijun; Zhou, Nan; Marnay, Chris
2006-06-14
In this study, referring to the Distributed Energy Resources Customer Adoption Model (DER-CAM) which was developed by the Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), E-GAMS programmer is developed with a research of database of energy tariffs, DER (Distributed Energy Resources) technology cost and performance characteristics, and building energy consumption in Japan. E-GAMS is a tool designed to find the optimal combination of installed equipment and an idealized operating schedule to minimize a site's energy bills. In this research, by using E-GAMS, we present a tool to select the optimal combination of distributed energy system for an Ecological-Campus, Kitakyushu, Science and Research Park (KSRP). We discuss the effects of the combination of distributed energy technologies on the energy saving, economic efficiency and environmental benefits.
Zacà, Ilaria; D’Agostino, Delia; Maria Congedo, Paolo; Baglivo, Cristina
2015-01-01
The data reported in this article refers to input and output information related to the research articles entitled Assessment of cost-optimality and technical solutions in high performance multi-residential buildings in the Mediterranean area by Zacà et al. (Assessment of cost-optimality and technical solutions in high performance multi-residential buildings in the Mediterranean area, in press.) and related to the research article Cost-optimal analysis and technical comparison between standard and high efficient mono residential buildings in a warm climate by Baglivo et al. (Energy, 2015, 10.1016/j.energy.2015.02.062, in press). PMID:26217793
Model Predictive Control-based Optimal Coordination of Distributed Energy Resources
Mayhorn, Ebony T.; Kalsi, Karanjit; Lian, Jianming; Elizondo, Marcelo A.
2013-04-03
Distributed energy resources, such as renewable energy resources (wind, solar), energy storage and demand response, can be used to complement conventional generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging, especially in isolated systems. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation performance. The goals of the optimization problem are to minimize fuel costs and maximize the utilization of wind while considering equipment life of generators and energy storage. Model predictive control (MPC) is used to solve a look-ahead dispatch optimization problem and the performance is compared to an open loop look-ahead dispatch problem. Simulation studies are performed to demonstrate the efficacy of the closed loop MPC in compensating for uncertainties and variability caused in the system.
Model Predictive Control-based Optimal Coordination of Distributed Energy Resources
Mayhorn, Ebony T.; Kalsi, Karanjit; Lian, Jianming; Elizondo, Marcelo A.
2013-01-07
Distributed energy resources, such as renewable energy resources (wind, solar), energy storage and demand response, can be used to complement conventional generators. The uncertainty and variability due to high penetration of wind makes reliable system operations and controls challenging, especially in isolated systems. In this paper, an optimal control strategy is proposed to coordinate energy storage and diesel generators to maximize wind penetration while maintaining system economics and normal operation performance. The goals of the optimization problem are to minimize fuel costs and maximize the utilization of wind while considering equipment life of generators and energy storage. Model predictive control (MPC) is used to solve a look-ahead dispatch optimization problem and the performance is compared to an open loop look-ahead dispatch problem. Simulation studies are performed to demonstrate the efficacy of the closed loop MPC in compensating for uncertainties and variability caused in the system.
The Automatic Formulating Method of the Optimal Operating Planning Problem for Energy Supply Systems
NASA Astrophysics Data System (ADS)
Suzuki, Naohiko; Ueda, Takaharu; Sasakawa, Koichi
The problem of the optimal operating planning for energy supply system is formulated as mixed-integer linear programming (MILP), but, it is too complicated for most untrained operators with little experience to apply the method. This paper proposes an automatic evaluating method of the optimal operating planning for energy supply system in using simple data. The problem can be formulated only from characteristics of equipment, tariff of input energy, and energy demands. The connection of equipment is defined as a matrix, and generated from property data of equipment. The constraints and objective function of the problem are generated from relation-ship data in the matrix and characteristics of equipment. An optimization calculation for the problem is automatically carried out. It is confirmed that any operator can evaluate many alternative configurations of the energy supply systems.
Sensory Agreement Guides Kinetic Energy Optimization of Arm Movements during Object Manipulation
Farshchiansadegh, Ali; Melendez-Calderon, Alejandro; Ranganathan, Rajiv; Murphey, Todd D.; Mussa-Ivaldi, Ferdinando A.
2016-01-01
The laws of physics establish the energetic efficiency of our movements. In some cases, like locomotion, the mechanics of the body dominate in determining the energetically optimal course of action. In other tasks, such as manipulation, energetic costs depend critically upon the variable properties of objects in the environment. Can the brain identify and follow energy-optimal motions when these motions require moving along unfamiliar trajectories? What feedback information is required for such optimal behavior to occur? To answer these questions, we asked participants to move their dominant hand between different positions while holding a virtual mechanical system with complex dynamics (a planar double pendulum). In this task, trajectories of minimum kinetic energy were along curvilinear paths. Our findings demonstrate that participants were capable of finding the energy-optimal paths, but only when provided with veridical visual and haptic information pertaining to the object, lacking which the trajectories were executed along rectilinear paths. PMID:27035587
Sensory Agreement Guides Kinetic Energy Optimization of Arm Movements during Object Manipulation.
Farshchiansadegh, Ali; Melendez-Calderon, Alejandro; Ranganathan, Rajiv; Murphey, Todd D; Mussa-Ivaldi, Ferdinando A
2016-04-01
The laws of physics establish the energetic efficiency of our movements. In some cases, like locomotion, the mechanics of the body dominate in determining the energetically optimal course of action. In other tasks, such as manipulation, energetic costs depend critically upon the variable properties of objects in the environment. Can the brain identify and follow energy-optimal motions when these motions require moving along unfamiliar trajectories? What feedback information is required for such optimal behavior to occur? To answer these questions, we asked participants to move their dominant hand between different positions while holding a virtual mechanical system with complex dynamics (a planar double pendulum). In this task, trajectories of minimum kinetic energy were along curvilinear paths. Our findings demonstrate that participants were capable of finding the energy-optimal paths, but only when provided with veridical visual and haptic information pertaining to the object, lacking which the trajectories were executed along rectilinear paths. PMID:27035587
Yokoyama, Ryohei; Ito, Koichi . Dept. of Energy Systems Engineering); Yuasa, Yoshiro . Technical Research Center)
1994-11-01
A deterministic approach to optimal unit sizing is presented for hybrid power generation systems utilizing photovoltaic and wind energy. Device capacities and electric contract demand are determined so as to minimize the annual total cost and annual energy consumption from the viewpoints of economy and energy saving or reduction in NO[sub x] and CO[sub 2] emission, respectively. This optimization problem is considered as a multiobjective one, and a discrete set of Pareto optimal solutions is derived numerically by using the weighting method. Two systems interconnected with the electric power grid are investigated: one has the option of reverse electricity flow into the grid, and the other has no option. By carrying out some case studies, the tradeoff relationships between the two objectives as well as the optimal values of device capacities are clarified. The influence of electricity deficit on unit sizing is also investigated.
Optimization of Passive Low Power Wireless Electromagnetic Energy Harvesters
Nimo, Antwi; Grgić, Dario; Reindl, Leonhard M.
2012-01-01
This work presents the optimization of antenna captured low power radio frequency (RF) to direct current (DC) power converters using Schottky diodes for powering remote wireless sensors. Linearized models using scattering parameters show that an antenna and a matched diode rectifier can be described as a form of coupled resonator with different individual resonator properties. The analytical models show that the maximum voltage gain of the coupled resonators is mainly related to the antenna, diode and load (remote sensor) resistances at matched conditions or resonance. The analytical models were verified with experimental results. Different passive wireless RF power harvesters offering high selectivity, broadband response and high voltage sensitivity are presented. Measured results show that with an optimal resistance of antenna and diode, it is possible to achieve high RF to DC voltage sensitivity of 0.5 V and efficiency of 20% at −30 dBm antenna input power. Additionally, a wireless harvester (rectenna) is built and tested for receiving range performance. PMID:23202014
Optimization of passive low power wireless electromagnetic energy harvesters.
Nimo, Antwi; Grgić, Dario; Reindl, Leonhard M
2012-01-01
This work presents the optimization of antenna captured low power radio frequency (RF) to direct current (DC) power converters using Schottky diodes for powering remote wireless sensors. Linearized models using scattering parameters show that an antenna and a matched diode rectifier can be described as a form of coupled resonator with different individual resonator properties. The analytical models show that the maximum voltage gain of the coupled resonators is mainly related to the antenna, diode and load (remote sensor) resistances at matched conditions or resonance. The analytical models were verified with experimental results. Different passive wireless RF power harvesters offering high selectivity, broadband response and high voltage sensitivity are presented. Measured results show that with an optimal resistance of antenna and diode, it is possible to achieve high RF to DC voltage sensitivity of 0.5 V and efficiency of 20% at -30 dBm antenna input power. Additionally, a wireless harvester (rectenna) is built and tested for receiving range performance. PMID:23202014
2013-01-01
Background Childhood obesity is a recognised public health problem and around 25% of Australian children are overweight or obese. A major contributor is the obesogenic environment which encourages over consumption of energy dense nutrient poor food. Taxation is commonly proposed as a mechanism to reduce consumption of poor food choices and hence reduce rates of obesity and overweight in the community. Methods/Design An economic model will be developed to assess the lifetime benefits and costs to a cohort of Australian children by reducing energy dense nutrient poor food consumption through taxation mechanisms. The model inputs will be derived from a series of smaller studies. Food options for taxation will be derived from literature and expert opinion, the acceptability and impact of price changes will be explored through a Citizen’s Jury and a discrete choice experiment and price elasticities will be derived from the discrete choice experiment and consumption data. Discussion The health care costs of managing rising levels of obesity are a challenge for all governments. This study will provide a unique contribution to the international knowledge base by engaging a variety of robust research techniques, with a multidisciplinary focus and be responsive to consumers from diverse socio-economic backgrounds. PMID:24330325
Control and Room Temperature Optimization of Energy Efficient Buildings
Djouadi, Seddik M; Kuruganti, Phani Teja
2012-01-01
The building sector consumes a large part of the energy used in the United States and is responsible for nearly 40% of greenhouse gas emissions. It is therefore economically and environmentally important to reduce the building energy consumption to realize massive energy savings. In this paper, a method to control room temperature in buildings is proposed. The approach is based on a distributed parameter model represented by a three dimensional (3D) heat equation in a room with heater/cooler located at ceiling. The latter is resolved using finite element methods, and results in a model for room temperature with thousands of states. The latter is not amenable to control design. A reduced order model of only few states is then derived using Proper Orthogonal Decomposition (POD). A Linear Quadratic Regulator (LQR) is computed based on the reduced model, and applied to the full order model to control room temperature.
Chen, Zhongxian; Yu, Haitao; Wen, Cheng
2014-01-01
The goal of direct drive ocean wave energy extraction system is to convert ocean wave energy into electricity. The problem explored in this paper is the design and optimal control for the direct drive ocean wave energy extraction system. An optimal control method based on internal model proportion integration differentiation (IM-PID) is proposed in this paper though most of ocean wave energy extraction systems are optimized by the structure, weight, and material. With this control method, the heavy speed of outer heavy buoy of the energy extraction system is in resonance with incident wave, and the system efficiency is largely improved. Validity of the proposed optimal control method is verified in both regular and irregular ocean waves, and it is shown that IM-PID control method is optimal in that it maximizes the energy conversion efficiency. In addition, the anti-interference ability of IM-PID control method has been assessed, and the results show that the IM-PID control method has good robustness, high precision, and strong anti-interference ability. PMID:25152913
Chen, Zhongxian; Yu, Haitao; Wen, Cheng
2014-01-01
The goal of direct drive ocean wave energy extraction system is to convert ocean wave energy into electricity. The problem explored in this paper is the design and optimal control for the direct drive ocean wave energy extraction system. An optimal control method based on internal model proportion integration differentiation (IM-PID) is proposed in this paper though most of ocean wave energy extraction systems are optimized by the structure, weight, and material. With this control method, the heavy speed of outer heavy buoy of the energy extraction system is in resonance with incident wave, and the system efficiency is largely improved. Validity of the proposed optimal control method is verified in both regular and irregular ocean waves, and it is shown that IM-PID control method is optimal in that it maximizes the energy conversion efficiency. In addition, the anti-interference ability of IM-PID control method has been assessed, and the results show that the IM-PID control method has good robustness, high precision, and strong anti-interference ability. PMID:25152913
NASA Astrophysics Data System (ADS)
Haji Hosseinloo, Ashkan; Turitsyn, Konstantin
2016-05-01
Vibratory energy harvesters as potential replacements for conventional batteries are not as robust as batteries. Their performance can drastically deteriorate in the presence of uncertainty in their parameters. Parametric uncertainty is inevitable with any physical device mainly due to manufacturing tolerances, defects, and environmental effects such as temperature and humidity. Hence, uncertainty propagation analysis and optimization under uncertainty seem indispensable with any energy harvester design. Here we propose a new modeling philosophy for optimization under uncertainty; optimization for the worst-case scenario (minimum power) rather than for the ensemble expectation of the power. The proposed optimization philosophy is practically very useful when there is a minimum requirement on the harvested power. We formulate the problems of uncertainty propagation and optimization under uncertainty in a generic and architecture-independent fashion, and then apply them to a single-degree-of-freedom linear piezoelectric energy harvester with uncertainty in its different parameters. The simulation results show that there is a significant improvement in the worst-case power of the designed harvester compared to that of a naively optimized (deterministically optimized) harvester. For instance, for a 10% uncertainty in the natural frequency of the harvester (in terms of its standard deviation) this improvement is about 570%.
Influence and optimization of the electrodes position in a piezoelectric energy harvesting flag
NASA Astrophysics Data System (ADS)
Piñeirua, Miguel; Doaré, Olivier; Michelin, Sébastien
2015-06-01
Fluttering piezoelectric plates may harvest energy from a fluid flow by converting the plate's mechanical deformation into electric energy in an output circuit. This work focuses on the influence of the arrangement of the piezoelectric electrodes along the plate's surface on the energy harvesting efficiency of the system, using a combination of experiments and numerical simulations. A weakly nonlinear model of a plate in axial flow, equipped with a discrete number of piezoelectric patches is derived and confronted to experimental results. Numerical simulations are then used to optimize the position and dimensions of the piezoelectric electrodes. These optimal configurations can be understood physically in the limit of small and large electromechanical coupling.
Optimal energy resolution of a hemispherical analyzer with virtual entry
NASA Astrophysics Data System (ADS)
Zouros, T. J. M.; Benis, E. P.
2005-02-01
For an ideal hemispherical deflector analyzer (HDA) utilizing a virtual entry aperture whose size is controlled by an injection lens, the "slit" and angular contributions to the overall base resolution RB are not independent, but constrained by the Helmholtz-Lagrange law. Thus, RB becomes a function of the linear lens magnification ∣ML∣ and has a minimum, RBo¯≡RB(∣ML∣o), at the optimal magnification ∣ML∣=∣ML∣o. RBo¯ and ∣ML∣o are shown to be analytic expressions of basic experimental parameters. RBo¯ is thus the ultimate resolution that can be attained in this case. The generality and simplicity of this result should be very helpful in the efficient design and performance evaluation of any modern HDA.
New Perspectives in Thermoelectric Energy Recovery System Design Optimization
NASA Astrophysics Data System (ADS)
Hendricks, Terry J.; Karri, Naveen K.; Hogan, Tim P.; Cauchy, Charles J.
2013-07-01
It is highly desirable to develop technologies that recover the large amounts of waste heat generated worldwide in industrial processes, automotive transportation, diesel engine exhaust, military generators, and incinerators to increase fuel efficiency and reduce CO2 production and the environmental footprint of these applications. Recent work has investigated new thermoelectric (TE) materials and systems that can operate at higher performance levels and show a viable pathway to lightweight, small-form-factor, advanced thermoelectric generator (TEG) systems to recover waste heat in many of these applications. New TE materials include nanocomposite materials such as lead-antimony-silver-telluride (LAST) and lead-antimony-silver-tin-telluride (LASTT) compounds. These new materials have created opportunities for high-performance, segmented-element TE devices. New higher-performance TE devices segmenting LAST/LASTT materials with bismuth telluride have been designed and fabricated. Sectioned TEG systems using these new TE devices and materials have been designed. Integrated heat exchanger/TE device system analyses of sectioned TE system designs have been performed, creating unique efficiency-power maps that provide better understanding and comparisons of design tradeoffs and nominal and off-nominal system performance conditions. New design perspectives and mathematical foundations in optimization of sectioned TE design approaches are discussed that provide insight on how to optimize such sectioned TE systems. System performance analyses using ANSYS® TE modeling capabilities have integrated heat exchanger performance models with ANSYS® TE models to extend its analysis capabilities beyond simple constant hot-side and cold-side temperature conditions. Analysis results portray external resistance effects, matched load conditions, and maximum power versus maximum efficiency points simultaneously, and show that maximum TE power occurs at external resistances slightly
Energy-Aware Multipath Routing Scheme Based on Particle Swarm Optimization in Mobile Ad Hoc Networks
Robinson, Y. Harold; Rajaram, M.
2015-01-01
Mobile ad hoc network (MANET) is a collection of autonomous mobile nodes forming an ad hoc network without fixed infrastructure. Dynamic topology property of MANET may degrade the performance of the network. However, multipath selection is a great challenging task to improve the network lifetime. We proposed an energy-aware multipath routing scheme based on particle swarm optimization (EMPSO) that uses continuous time recurrent neural network (CTRNN) to solve optimization problems. CTRNN finds the optimal loop-free paths to solve link disjoint paths in a MANET. The CTRNN is used as an optimum path selection technique that produces a set of optimal paths between source and destination. In CTRNN, particle swarm optimization (PSO) method is primly used for training the RNN. The proposed scheme uses the reliability measures such as transmission cost, energy factor, and the optimal traffic ratio between source and destination to increase routing performance. In this scheme, optimal loop-free paths can be found using PSO to seek better link quality nodes in route discovery phase. PSO optimizes a problem by iteratively trying to get a better solution with regard to a measure of quality. The proposed scheme discovers multiple loop-free paths by using PSO technique. PMID:26819966
Robinson, Y Harold; Rajaram, M
2015-01-01
Mobile ad hoc network (MANET) is a collection of autonomous mobile nodes forming an ad hoc network without fixed infrastructure. Dynamic topology property of MANET may degrade the performance of the network. However, multipath selection is a great challenging task to improve the network lifetime. We proposed an energy-aware multipath routing scheme based on particle swarm optimization (EMPSO) that uses continuous time recurrent neural network (CTRNN) to solve optimization problems. CTRNN finds the optimal loop-free paths to solve link disjoint paths in a MANET. The CTRNN is used as an optimum path selection technique that produces a set of optimal paths between source and destination. In CTRNN, particle swarm optimization (PSO) method is primly used for training the RNN. The proposed scheme uses the reliability measures such as transmission cost, energy factor, and the optimal traffic ratio between source and destination to increase routing performance. In this scheme, optimal loop-free paths can be found using PSO to seek better link quality nodes in route discovery phase. PSO optimizes a problem by iteratively trying to get a better solution with regard to a measure of quality. The proposed scheme discovers multiple loop-free paths by using PSO technique. PMID:26819966
The relation between the shop floor energy system and the manufacturing process optimality
NASA Astrophysics Data System (ADS)
Badea, N.; Frumuşanu, G.; Epureanu, A.
2015-11-01
Nowadays, the overhead expenses are a significant component of the manufacturing cost. The expenditures occasioned by running the shop floor energy system are one of the most important among the overhead expenses. However, the manufacturing process optimization actually does not take into account these expenses. More than that, the expenses for running the shop floor energy system are not constant, varying after the external environment seasonal conditions, and they are depending on several issues, like the building's energetic exchange with its environment, or the loading degree of the machine tools from the shop floor. This paper approaches the relation between the shop floor energy system expenditures, on one hand, and the manufacturing process optimality, on the other hand. A case study, revealing the influence of the shop floor energy system on the manufacturing cost-optimal solution is also included.
Optimizing Lidar Scanning Strategies for Wind Energy Measurements (Invited)
NASA Astrophysics Data System (ADS)
Newman, J. F.; Bonin, T. A.; Klein, P.; Wharton, S.; Chilson, P. B.
2013-12-01
Environmental concerns and rising fossil fuel prices have prompted rapid development in the renewable energy sector. Wind energy, in particular, has become increasingly popular in the United States. However, the intermittency of available wind energy makes it difficult to integrate wind energy into the power grid. Thus, the expansion and successful implementation of wind energy requires accurate wind resource assessments and wind power forecasts. The actual power produced by a turbine is affected by the wind speeds and turbulence levels experienced across the turbine rotor disk. Because of the range of measurement heights required for wind power estimation, remote sensing devices (e.g., lidar) are ideally suited for these purposes. However, the volume averaging inherent in remote sensing technology produces turbulence estimates that are different from those estimated by a sonic anemometer mounted on a standard meteorological tower. In addition, most lidars intended for wind energy purposes utilize a standard Doppler beam-swinging or Velocity-Azimuth Display technique to estimate the three-dimensional wind vector. These scanning strategies are ideal for measuring mean wind speeds but are likely inadequate for measuring turbulence. In order to examine the impact of different lidar scanning strategies on turbulence measurements, a WindCube lidar, a scanning Halo lidar, and a scanning Galion lidar were deployed at the Southern Great Plains Atmospheric Radiation Measurement (ARM) site in Summer 2013. Existing instrumentation at the ARM site, including a 60-m meteorological tower and an additional scanning Halo lidar, were used in conjunction with the deployed lidars to evaluate several user-defined scanning strategies. For part of the experiment, all three scanning lidars were pointed at approximately the same point in space and a tri-Doppler analysis was completed to calculate the three-dimensional wind vector every 1 second. In another part of the experiment, one of
Optimization of a Ranchero driven high energy liner driver system
Atchison, Walter L; Kaul, Ann; Rousculp, Chris L; Watt, Robert G
2008-01-01
An experimental series is planned to implode a dense heavy liner to a velocity in excess of 1 cm/microsecond (10 mm/microsecond) using a RANCHERO coaxial explosive flux compression generator. The goal of this study is to choose the liner mass and starting radius that will deliver the greatest amount of kinetic energy to a target at 1 cm final radius. In this study we used the 1D-MHD simulation code RA YEN to search for the proper initial conditions. The results will be used as a starting point for 2-D simulations and preliminary designs for the first experiments planned in the 2009/2010 time frame. The preliminary results indicate that a liner velocity of 1.25 cm/microsecond and a kinetic energy of greater than 4 megajoules may be possible.
A Combined Energy and Geoengineering Optimization Model (CEAGOM) for Climate Policy Analysis
NASA Astrophysics Data System (ADS)
Anasis, John George
One of the greatest challenges that will face humanity in the 21 st century is the issue of climate change brought about by emissions of greenhouse gases. Energy use is one of the primary sources of greenhouse gas emissions. However, it is also one of the most important contributors to improved human welfare over the past two centuries and will continue to be so for years to come. This quandary has led a number of researchers to suggest that geoengineering may be required in order to allow for continued use of fossil fuels while at the same time mitigating the effects of the associated greenhouse gas emissions on the global climate. The goal of this research was to develop a model that would allow decision-makers and policy analysts to assess the optimal mix of energy and geoengineering resources needed to meet global or regional energy demand at the lowest cost while accounting for appropriate emissions, greenhouse gas concentration, or temperature rise constraints. The resulting software model is called the Combined Energy and Geoengineering Optimization Model (CEAGOM). CEAGOM was then used to analyze the recently announced U.S.-China emissions agreement and to assess what the optimal global energy resource mix might be over the course of the 21 st century, including the associated potential need for geoengineering. These analyses yielded optimal mixes of energy and geoengineering resources that could be used to inform regional and global energy and climate management strategies.
NASA Astrophysics Data System (ADS)
Zulai, Luis G. T.; Durand, Fábio R.; Abrão, Taufik
2015-05-01
In this article, an energy-efficiency mechanism for next-generation passive optical networks is investigated through heuristic particle swarm optimization. Ten-gigabit Ethernet-wavelength division multiplexing optical code division multiplexing-passive optical network next-generation passive optical networks are based on the use of a legacy 10-gigabit Ethernet-passive optical network with the advantage of using only an en/decoder pair of optical code division multiplexing technology, thus eliminating the en/decoder at each optical network unit. The proposed joint mechanism is based on the sleep-mode power-saving scheme for a 10-gigabit Ethernet-passive optical network, combined with a power control procedure aiming to adjust the transmitted power of the active optical network units while maximizing the overall energy-efficiency network. The particle swarm optimization based power control algorithm establishes the optimal transmitted power in each optical network unit according to the network pre-defined quality of service requirements. The objective is controlling the power consumption of the optical network unit according to the traffic demand by adjusting its transmitter power in an attempt to maximize the number of transmitted bits with minimum energy consumption, achieving maximal system energy efficiency. Numerical results have revealed that it is possible to save 75% of energy consumption with the proposed particle swarm optimization based sleep-mode energy-efficiency mechanism compared to 55% energy savings when just a sleeping-mode-based mechanism is deployed.
An Energy-Aware Trajectory Optimization Layer for sUAS
NASA Astrophysics Data System (ADS)
Silva, William A.
The focus of this work is the implementation of an energy-aware trajectory optimization algorithm that enables small unmanned aircraft systems (sUAS) to operate in unknown, dynamic severe weather environments. The software is designed as a component of an Energy-Aware Dynamic Data Driven Application System (EA-DDDAS) for sUAS. This work addresses the challenges of integrating and executing an online trajectory optimization algorithm during mission operations in the field. Using simplified aircraft kinematics, the energy-aware algorithm enables extraction of kinetic energy from measured winds to optimize thrust use and endurance during flight. The optimization layer, based upon a nonlinear program formulation, extracts energy by exploiting strong wind velocity gradients in the wind field, a process known as dynamic soaring. The trajectory optimization layer extends the energy-aware path planner developed by Wenceslao Shaw-Cortez te{Shaw-cortez2013} to include additional mission configurations, simulations with a 6-DOF model, and validation of the system with flight testing in June 2015 in Lubbock, Texas. The trajectory optimization layer interfaces with several components within the EA-DDDAS to provide an sUAS with optimal flight trajectories in real-time during severe weather. As a result, execution timing, data transfer, and scalability are considered in the design of the software. Severe weather also poses a measure of unpredictability to the system with respect to communication between systems and available data resources during mission operations. A heuristic mission tree with different cost functions and constraints is implemented to provide a level of adaptability to the optimization layer. Simulations and flight experiments are performed to assess the efficacy of the trajectory optimization layer. The results are used to assess the feasibility of flying dynamic soaring trajectories with existing controllers as well as to verify the interconnections between
Trimode Power Converter optimizes PV, diesel and battery energy sources
O`Sullivan, G.; Bonn, R.; Bower, W.
1994-07-01
Conservatively, there are 100,000 localities in the world waiting for the benefits that electricity can provide, and many of these are in climates where sunshine is plentiful. With these locations in mind a prototype 30 kW hybrid system has been assembled at Sandia to prove the reliability and economics of photovoltaic, diesel and battery energy sources managed by an autonomous power converter. In the Trimode Power Converter the same power parts, four IGBT`s with an isolation transformer and filter components, serve as rectifier and charger to charge the battery from the diesel; as a stand-alone inverter to convert PV and battery energy to AC; and, as a parallel inverter with the diesel-generator to accommodate loads larger than the rating of the diesel. Whenever the diesel is supplying the load, an algorithm assures that the diesel is running at maximum efficiency by regulating the battery charger operating point. Given the profile of anticipated solar energy, the cost of transporting diesel fuel to a remote location and a five year projection of load demand, a method to size the PV array, battery and diesel for least cost is developed.
A new energy optimizing control strategy for switched reluctance motors
Kjaer, P.C.; Nielsen, P.
1995-09-01
This paper describes a new and machine-independent method to minimize the energy consumption of a speed controlled Switched Reluctance Motor (SRM). The control strategy is to vary the duty cycle of the applied dc voltage in order to obtain the desired speed quickly and when operating in steady-state vary the turn-on angle ({alpha}{sub on}) of the phase voltage to minimize the energy consumption. The power flow is measured in the dc-link and used to control the turn-on angle. Simulations carried out on a three-phase 6/4 pole SRM justify the algorithm and the physical implementation in a Siemens SAB 80C517A microcontroller is described. Measurements on two different load systems show it is possible to minimize the energy consumption on-line in a speed controlled Switched Reluctance Motor without losing the dynamic performance. A comparison with an ordinary mode-shift controlled SRM shows more than an 8% increase in overall efficiency for some operation points. The algorithm is fully applicable to other Switched Reluctance Motors at other power levels or with other pole configurations.
An optimal energy estimator to reduce correlated noise for the EXO-200 light readout
NASA Astrophysics Data System (ADS)
Davis, C. G.; Hall, C.; Albert, J. B.; Barbeau, P. S.; Beck, D.; Belov, V.; Breidenbach, M.; Brunner, T.; Burenkov, A.; Cao, G. F.; Cen, W. R.; Chambers, C.; Cleveland, B.; Coon, M.; Craycraft, A.; Daniels, T.; Danilov, M.; Daugherty, S. J.; Davis, J.; Delaquis, S.; Der Mesrobian-Kabakian, A.; DeVoe, R.; Didberidze, T.; Dilling, J.; Dolgolenko, A.; Dolinski, M. J.; Dunford, M.; Fairbank, W., Jr.; Farine, J.; Feldmeier, W.; Feyzbakhsh, S.; Fierlinger, P.; Fudenberg, D.; Gornea, R.; Graham, K.; Gratta, G.; Hughes, M.; Jewell, M. J.; Johnson, A.; Johnson, T. N.; Johnston, S.; Karelin, A.; Kaufman, L. J.; Killick, R.; Koffas, T.; Kravitz, S.; Krücken, R.; Kuchenkov, A.; Kumar, K. S.; Leonard, D. S.; Licciardi, C.; Lin, Y. H.; Ling, J.; MacLellan, R.; Marino, M. G.; Mong, B.; Moore, D.; Njoya, O.; Nelson, R.; Odian, A.; Ostrovskiy, I.; Piepke, A.; Pocar, A.; Prescott, C. Y.; Retière, F.; Rowson, P. C.; Russell, J. J.; Schubert, A.; Sinclair, D.; Smith, E.; Stekhanov, V.; Tarka, M.; Tolba, T.; Tsang, R.; Twelker, K.; Vuilleumier, J.-L.; Waite, A.; Walton, J.; Walton, T.; Weber, M.; Wen, L. J.; Wichoski, U.; Wood, J.; Yang, L.; Yen, Y.-R.; Zeldovich, O. Ya.
2016-07-01
The energy resolution of the EXO-200 detector is limited by electronics noise in the measurement of the scintillation response. Here we present a new technique to extract optimal scintillation energy measurements for signals split across multiple channels in the presence of correlated noise. The implementation of these techniques improves the energy resolution of the detector at the neutrinoless double beta decay Q-value from [1.9641 ± 0.0039]% to [1.5820 ± 0.0044]%.
Proton energy optimization and reduction for intensity-modulated proton therapy.
Cao, Wenhua; Lim, Gino; Liao, Li; Li, Yupeng; Jiang, Shengpeng; Li, Xiaoqiang; Li, Heng; Suzuki, Kazumichi; Zhu, X Ronald; Gomez, Daniel; Zhang, Xiaodong
2014-11-01
Intensity-modulated proton therapy (IMPT) is commonly delivered via the spot-scanning technique. To 'scan' the target volume, the proton beam is controlled by varying its energy to penetrate the patient's body at different depths. Although scanning the proton beamlets or spots with the same energy can be as fast as 10-20 m s(-1), changing from one proton energy to another requires approximately two additional seconds. The total IMPT delivery time thus depends mainly on the number of proton energies used in a treatment. Current treatment planning systems typically use all proton energies that are required for the proton beam to penetrate in a range from the distal edge to the proximal edge of the target. The optimal selection of proton energies has not been well studied. In this study, we sought to determine the feasibility of optimizing and reducing the number of proton energies in IMPT planning. We proposed an iterative mixed-integer programming optimization method to select a subset of all available proton energies while satisfying dosimetric criteria. We applied our proposed method to six patient datasets: four cases of prostate cancer, one case of lung cancer, and one case of mesothelioma. The numbers of energies were reduced by 14.3%-18.9% for the prostate cancer cases, 11.0% for the lung cancer cases and 26.5% for the mesothelioma case. The results indicate that the number of proton energies used in conventionally designed IMPT plans can be reduced without degrading dosimetric performance. The IMPT delivery efficiency could be improved by energy layer optimization leading to increased throughput for a busy proton center in which a delivery system with slow energy switch is employed. PMID:25295881
Proton energy optimization and reduction for intensity-modulated proton therapy
Cao, Wenhua; Lim, Gino; Liao, Li; Li, Yupeng; Jiang, Shengpeng; Li, Xiaoqiang; Li, Heng; Suzuki, Kazumichi; Zhu, X. Ronald; Gomez, Daniel; Zhang, Xiaodong
2015-01-01
Intensity-modulated proton therapy (IMPT) is commonly delivered via the spot-scanning technique. To “scan” the target volume, the proton beam is controlled by varying its energy to penetrate the patient’s body at different depths. Although scanning the proton beamlets or spots with the same energy can be as fast as 10–20 m/s, changing from one proton energy to another requires approximately two additional seconds. The total IMPT delivery time thus depends mainly on the number of proton energies used in a treatment. Current treatment planning systems typically use all proton energies that are required for the proton beam to penetrate in a range from the distal edge to the proximal edge of the target. The optimal selection of proton energies has not been well studied. In this study, we sought to determine the feasibility of optimizing and reducing the number of proton energies in IMPT planning. We proposed an iterative mixed-integer programming optimization method to select a subset of all available proton energies while satisfying dosimetric criteria. We applied our proposed method to six patient datasets: four cases of prostate cancer, one case of lung cancer, and one case of mesothelioma. The numbers of energies were reduced by 14.3%–18.9% for the prostate cancer cases, 11.0% for the lung cancer cases, and 26.5% for the mesothelioma case. The results indicate that the number of proton energies used in conventionally designed IMPT plans can be reduced without degrading dosimetric performance. The IMPT delivery efficiency could be improved by energy layer optimization leading to increased throughput for a busy proton center in which a delivery system with slow energy switch is employed. PMID:25295881
Proton energy optimization and reduction for intensity-modulated proton therapy
NASA Astrophysics Data System (ADS)
Cao, Wenhua; Lim, Gino; Liao, Li; Li, Yupeng; Jiang, Shengpeng; Li, Xiaoqiang; Li, Heng; Suzuki, Kazumichi; Zhu, X. Ronald; Gomez, Daniel; Zhang, Xiaodong
2014-10-01
Intensity-modulated proton therapy (IMPT) is commonly delivered via the spot-scanning technique. To ‘scan’ the target volume, the proton beam is controlled by varying its energy to penetrate the patient’s body at different depths. Although scanning the proton beamlets or spots with the same energy can be as fast as 10-20 m s-1, changing from one proton energy to another requires approximately two additional seconds. The total IMPT delivery time thus depends mainly on the number of proton energies used in a treatment. Current treatment planning systems typically use all proton energies that are required for the proton beam to penetrate in a range from the distal edge to the proximal edge of the target. The optimal selection of proton energies has not been well studied. In this study, we sought to determine the feasibility of optimizing and reducing the number of proton energies in IMPT planning. We proposed an iterative mixed-integer programming optimization method to select a subset of all available proton energies while satisfying dosimetric criteria. We applied our proposed method to six patient datasets: four cases of prostate cancer, one case of lung cancer, and one case of mesothelioma. The numbers of energies were reduced by 14.3%-18.9% for the prostate cancer cases, 11.0% for the lung cancer cases and 26.5% for the mesothelioma case. The results indicate that the number of proton energies used in conventionally designed IMPT plans can be reduced without degrading dosimetric performance. The IMPT delivery efficiency could be improved by energy layer optimization leading to increased throughput for a busy proton center in which a delivery system with slow energy switch is employed.
Cardoso, Goncalo; Stadler, Michael; Bozchalui, Mohammed C.; Sharma, Ratnesh; Marnay, Chris; Barbosa-Povoa, Ana; Ferrao, Paulo
2013-12-06
The large scale penetration of electric vehicles (EVs) will introduce technical challenges to the distribution grid, but also carries the potential for vehicle-to-grid services. Namely, if available in large enough numbers, EVs can be used as a distributed energy resource (DER) and their presence can influence optimal DER investment and scheduling decisions in microgrids. In this work, a novel EV fleet aggregator model is introduced in a stochastic formulation of DER-CAM [1], an optimization tool used to address DER investment and scheduling problems. This is used to assess the impact of EV interconnections on optimal DER solutions considering uncertainty in EV driving schedules. Optimization results indicate that EVs can have a significant impact on DER investments, particularly if considering short payback periods. Furthermore, results suggest that uncertainty in driving schedules carries little significance to total energy costs, which is corroborated by results obtained using the stochastic formulation of the problem.
Optimal heading change with minimum energy loss for a hypersonic gliding vehicle
NASA Technical Reports Server (NTRS)
Calise, Anthony J.; Bae, Gyoung H.
1987-01-01
A three state model is presented for analyzing the problem of optimal changes in heading with minimum energy loss for a hypersonic gliding vehicle. A further model order reduction to a single state model is examined using singular perturbation theory. The optimal solution for the reduced problem defines an optimal altitude profile dependent on the current energy of the vehicle, and the corresponding optimal lift and bank angle. A separate boundary layer analysis, based on an expansion of the necessary conditions about the reduced solution, is used to account for altitude and flight path angle dynamics and to derive a guidance law in feedback form. The guidance law is evaluated for a hypothetical vehicle.
Optimization of energy transfer in microwave electrothermal thrusters
NASA Technical Reports Server (NTRS)
Sullivan, D. J.; Micci, M. M.
1993-01-01
Results are presented from preliminary tests conducted to evaluate the performance of a prototype microwave electrothermal thruster. The primary component of the device is a microwave resonant cavity. The device produces stable axial plasmas within a pressurized section of the cavity with the plasma positioned in the inlet region of the nozzle. Plasma stability is enhanced by axial power coupling, an optimal distribution of electric power density within the cavity, and a propellant gas flow which has a large vortical velocity component. The thruster has been operated with a number of propellant gases: helium, nitrogen, ammonia, and hydrogen. Plasmas can be formed in a reliable manner at cavity pressures of 1 kPa and incident power levels ranging from 50 W to 350 W, depending on the gas used, and can be operated at pressures up to 300 kPa at power levels up to 2200 W. Ideal performance results of vacuum Isp and thermal efficiency vs. specific power are presented for each gas. Representative results of this preliminary work are: He - Isp = 625 s, eta-thermal = 90 percent; N2 - Isp = 270 s, eta-thermal = 41 percent; NH3 - Isp = 475 s, eta-thermal= 55 percent; H2 - Isp = 1040 s, eta-thermal = 53 percent.
Computing intramolecular charge and energy transfer rates using optimal modes
Yang, Xunmo; Bittner, Eric R.
2015-06-28
In our recent work [X. Yang and E. R. Bittner, J. Phys. Chem. A 118, 5196 (2014)], we showed how to construct a reduced set of nuclear motions that capture the coupling between electronic and nuclear degrees of freedom over the course of an electronic transition. We construct these modes, referred to as “Lanczos modes,” by applying a search algorithm to find linear combinations of vibrational normal modes that optimize the electronic/nuclear coupling operator. Here, we analyze the irreducible representations of the dominant contributions of these modes and find that for the cases considered here, these belong to totally symmetric irreducible representations of the donor and acceptor moieties. Upon investigating the molecular geometry changes following the transition, we propose that the electronic transition process can be broken into two steps, in the agreement of Born-Oppenheimer approximation: a fast excitation transfer occurs, facilitated by the “primary Lanczos mode,” followed by slow nuclear relaxation on the final electronic diabatic surface.
Hayashibe, Mitsuhiro; Shimoda, Shingo
2014-01-01
A human motor system can improve its behavior toward optimal movement. The skeletal system has more degrees of freedom than the task dimensions, which incurs an ill-posed problem. The multijoint system involves complex interaction torques between joints. To produce optimal motion in terms of energy consumption, the so-called cost function based optimization has been commonly used in previous works.Even if it is a fact that an optimal motor pattern is employed phenomenologically, there is no evidence that shows the existence of a physiological process that is similar to such a mathematical optimization in our central nervous system.In this study, we aim to find a more primitive computational mechanism with a modular configuration to realize adaptability and optimality without prior knowledge of system dynamics.We propose a novel motor control paradigm based on tacit learning with task space feedback. The motor command accumulation during repetitive environmental interactions, play a major role in the learning process. It is applied to a vertical cyclic reaching which involves complex interaction torques.We evaluated whether the proposed paradigm can learn how to optimize solutions with a 3-joint, planar biomechanical model. The results demonstrate that the proposed method was valid for acquiring motor synergy and resulted in energy efficient solutions for different load conditions. The case in feedback control is largely affected by the interaction torques. In contrast, the trajectory is corrected over time with tacit learning toward optimal solutions.Energy efficient solutions were obtained by the emergence of motor synergy. During learning, the contribution from feedforward controller is augmented and the one from the feedback controller is significantly minimized down to 12% for no load at hand, 16% for a 0.5 kg load condition.The proposed paradigm could provide an optimization process in redundant system with dynamic-model-free and cost-function-free approach
From microscopic taxation and redistribution models to macroscopic income distributions
NASA Astrophysics Data System (ADS)
Bertotti, Maria Letizia; Modanese, Giovanni
2011-10-01
We present here a general framework, expressed by a system of nonlinear differential equations, suitable for the modeling of taxation and redistribution in a closed society. This framework allows one to describe the evolution of income distribution over the population and to explain the emergence of collective features based on knowledge of the individual interactions. By making different choices of the framework parameters, we construct different models, whose long-time behavior is then investigated. Asymptotic stationary distributions are found, which enjoy similar properties as those observed in empirical distributions. In particular, they exhibit power law tails of Pareto type and their Lorenz curves and Gini indices are consistent with some real world ones.
26 CFR 1.860C-1 - Taxation of holders of residual interests.
Code of Federal Regulations, 2011 CFR
2011-04-01
... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.860C-1 Taxation... (but not below zero) by— (i) First, the amount of any cash or the fair market value of any...
Optimal Time-Resource Allocation for Energy-Efficient Physical Activity Detection
Thatte, Gautam; Li, Ming; Lee, Sangwon; Emken, B. Adar; Annavaram, Murali; Narayanan, Shrikanth; Spruijt-Metz, Donna; Mitra, Urbashi
2011-01-01
The optimal allocation of samples for physical activity detection in a wireless body area network for health-monitoring is considered. The number of biometric samples collected at the mobile device fusion center, from both device-internal and external Bluetooth heterogeneous sensors, is optimized to minimize the transmission power for a fixed number of samples, and to meet a performance requirement defined using the probability of misclassification between multiple hypotheses. A filter-based feature selection method determines an optimal feature set for classification, and a correlated Gaussian model is considered. Using experimental data from overweight adolescent subjects, it is found that allocating a greater proportion of samples to sensors which better discriminate between certain activity levels can result in either a lower probability of error or energy-savings ranging from 18% to 22%, in comparison to equal allocation of samples. The current activity of the subjects and the performance requirements do not significantly affect the optimal allocation, but employing personalized models results in improved energy-efficiency. As the number of samples is an integer, an exhaustive search to determine the optimal allocation is typical, but computationally expensive. To this end, an alternate, continuous-valued vector optimization is derived which yields approximately optimal allocations and can be implemented on the mobile fusion center due to its significantly lower complexity. PMID:21796237
NASA Astrophysics Data System (ADS)
Miller, Michael; Strom, Ben; Breuer, Kenneth; Mandre, Shreyas
2014-11-01
We determine the feasibility of applying optimization algorithms to an oscillating hydrofoil's motion trajectory to determine maximum efficiency of energy capture. Optimization is performed using the Nelder-Meade downhill simplex method. The objective function is the energy captured measured experimentally in run-time with an oscillating hydrofoil capable of measuring mechanical energy capture in a laboratory flume. For sinusoidal trajectories, optimization is performed over pitch and heave amplitudes as well as frequency; this system is shown to be capable of optimization in run-time. The optimum efficiency of 30% is found for a pitch amplitude of 70°, a heave amplitude of 0.8* chord and a dimensionless frequency of 0.13. To treat non-sinusoidal trajectories, we expand them in a truncated Fourier series and consider the coefficients of this series as variables for optimization. The sinusoidal case is simply an extreme case of such a truncated Fourier series, with only one term in the series retained. We present a systematic method for optimization over general non-sinusoidal trajectories by including more and more terms in the Fourier series.
Near optimal energy selective x-ray imaging system performance with simple detectors
Alvarez, Robert E.
2010-02-15
Purpose: This article describes a method to achieve near optimal performance with low energy resolution detectors. Tapiovaara and Wagner [Phys. Med. Biol. 30, 519-529 (1985)] showed that an energy selective x-ray system using a broad spectrum source can produce images with a larger signal to noise ratio (SNR) than conventional systems using energy integrating or photon counting detectors. They showed that there is an upper limit to the SNR and that it can be achieved by measuring full spectrum information and then using an optimal energy dependent weighting. Methods: A performance measure is derived by applying statistical detection theory to an abstract vector space of the line integrals of the basis set coefficients of the two function approximation to the x-ray attenuation coefficient. The approach produces optimal results that utilize all the available energy dependent data. The method can be used with any energy selective detector and is applied not only to detectors using pulse height analysis (PHA) but also to a detector that simultaneously measures the total photon number and integrated energy, as discussed by Roessl et al. [Med. Phys. 34, 959-966 (2007)]. A generalization of this detector that improves the performance is introduced. A method is described to compute images with the optimal SNR using projections in a ''whitened'' vector space transformed so the noise is uncorrelated and has unit variance in both coordinates. Material canceled images with optimal SNR can also be computed by projections in this space. Results: The performance measure is validated by showing that it provides the Tapiovaara-Wagner optimal results for a detector with full energy information and also a conventional detector. The performance with different types of detectors is compared to the ideal SNR as a function of x-ray tube voltage and subject thickness. A detector that combines two bin PHA with a simultaneous measurement of integrated photon energy provides near ideal
Chen, Jian; Jia, Jie; Wen, Yingyou; Zhao, Dazhe
2014-01-01
Energy hole is an inherent problem caused by heavier traffic loads of sensor nodes nearer the sink because of more frequent data transmission, which is strongly dependent on the topology induced by the sensor deployment. In this paper, we propose an autonomous sensor redeployment algorithm to balance energy consumption and mitigate energy hole for unattended mobile sensor networks. First, with the target area divided into several equal width coronas, we present a mathematical problem modeling sensor node layout as well as transmission pattern to maximize network coverage and reduce communication cost. And then, by calculating the optimal node density for each corona to avoid energy hole, a fully distributed movement algorithm is proposed, which can achieve an optimal distribution quickly only by pushing or pulling its one-hop neighbors. The simulation results demonstrate that our algorithm achieves a much smaller average moving distance and a much longer network lifetime than existing algorithms and can eliminate the energy hole problem effectively. PMID:24949494
Energy and operation management of a microgrid using particle swarm optimization
NASA Astrophysics Data System (ADS)
Radosavljević, Jordan; Jevtić, Miroljub; Klimenta, Dardan
2016-05-01
This article presents an efficient algorithm based on particle swarm optimization (PSO) for energy and operation management (EOM) of a microgrid including different distributed generation units and energy storage devices. The proposed approach employs PSO to minimize the total energy and operating cost of the microgrid via optimal adjustment of the control variables of the EOM, while satisfying various operating constraints. Owing to the stochastic nature of energy produced from renewable sources, i.e. wind turbines and photovoltaic systems, as well as load uncertainties and market prices, a probabilistic approach in the EOM is introduced. The proposed method is examined and tested on a typical grid-connected microgrid including fuel cell, gas-fired microturbine, wind turbine, photovoltaic and energy storage devices. The obtained results prove the efficiency of the proposed approach to solve the EOM of the microgrids.
Jia, Jie; Wen, Yingyou; Zhao, Dazhe
2014-01-01
Energy hole is an inherent problem caused by heavier traffic loads of sensor nodes nearer the sink because of more frequent data transmission, which is strongly dependent on the topology induced by the sensor deployment. In this paper, we propose an autonomous sensor redeployment algorithm to balance energy consumption and mitigate energy hole for unattended mobile sensor networks. First, with the target area divided into several equal width coronas, we present a mathematical problem modeling sensor node layout as well as transmission pattern to maximize network coverage and reduce communication cost. And then, by calculating the optimal node density for each corona to avoid energy hole, a fully distributed movement algorithm is proposed, which can achieve an optimal distribution quickly only by pushing or pulling its one-hop neighbors. The simulation results demonstrate that our algorithm achieves a much smaller average moving distance and a much longer network lifetime than existing algorithms and can eliminate the energy hole problem effectively. PMID:24949494
NASA Astrophysics Data System (ADS)
Nakasone, Paulo H.; Kiyono, César Y.; Silva, Emílio C. N.
2008-03-01
Sensors and actuators based on piezoelectric plates have shown increasing demand in the field of smart structures, including the development of actuators for cooling and fluid pumping applications and transducers for novel energy harvesting devices. This project involves the development of a finite element and topology optimization software to design piezoelectric sensors, actuators and energy harvesting devices by distributing piezoelectric material over a metallic plate in order to achieve a desired dynamic behavior with specified vibration frequencies. The finite element employs a general formulation capable of representing both direct and converse piezoelectric effects. It is based on the MITC formulation, which is reliable, efficient and avoids the shear locking problem. The topology optimization formulation is based on the PEMAP-P model (Piezoelectric Material with Penalization and Polarization), where the design variables are the pseudo-densities that describe the amount of piezoelectric material at each finite element. The optimization problem has a multi-objective function, which can be subdivided into three distinct problems: maximization of mean transduction, minimization of mean compliance and optimization of Eigenvalues. The first one is responsible for maximizing the amount of electric energy converted into elastic energy, the second one guarantees that the structure does not become excessively flexible and the third one tunes the structure for a given frequency. This paper presents the implementation of the finite element and optimization software and shows preliminary results achieved.
NASA Astrophysics Data System (ADS)
Haque, Md. Rejaul; Chowdhury, M. Arshad Zahangir; Goswami, Anjan
2016-07-01
A two-dimensional numerical study of flow induced vibration is reported in this paper to investigate flow over a semi-cricular D-shaped bluff body oriented at different angles-of-attack to determine an optimized design for energy harvesting. Bluff body structure governs fluid streamlines; therefore obtaining a suitable range of "lock in frequency" for energy harvesting purpose is dependent on refining and optimizing bluff body's shape and structure. A cantilever based novel energy harvester design incorporates the suitable angle-of-attack for optimized performance. This optimization was done by performing computations for 30°, 60° and 90° angles-of-attack. The frequency of vibration of the body was calculated at different Reynolds Number. A Fast Fourier Transformation yielded frequency of vortex shedding. From the wake velocity profile, lift oscillation and frequency of vortex shedding is estimated. Strouhal numbers of the body were analyzed at different angles-of-attack. A higher synchronized bandwidth of shedding frequencies is an indication of an optimized harvester design at different Reynolds number. The `D' shaped bluff bodies (with angle of attack of 30°,60° and 90°) are more suitable than that of cylindrical shaped bluff bodies. The research clearly stated that, bluff bodies shape has a prominent influence on vortex induced vibration and semicircular bluff body gives the highest vibration or energy under stated conditions.
NASA Astrophysics Data System (ADS)
Li, Jingcheng; Jang, Shinae; Tang, Jiong
2013-04-01
Wireless sensor network is one of the prospective methods for railway monitoring due to the long-term operation and low-maintenance performances. How to supply power to the wireless sensor nodes has drawn much attention recently. In railway monitoring, the idea of converting ambient vibration energy from vibration of railway track induced by passing trains to electric energy has made it a potential way for powering the wireless sensor nodes. Nowadays, most of vibration based energy harvesters are designed at resonance. However, as railway vibration frequency is a wide band range, how to design an energy harvester working at that range is critical. In this paper, the energy consumption of the wireless smart sensor platform, Imote2, at different working states were investigated. Based on the energy consumption, a design of a bimorph cantilever piezoelectric energy harvester has been optimized to generate maximum average power between a wide-band frequency range. Significant power and current outputs have been increased after optimal design. Finally, the rechargeable battery life for supplying the Imote2 for railway monitoring is predicted by using the optimized piezoelectric energy harvesting system.
Optimal throughput for cognitive radio with energy harvesting in fading wireless channel.
Vu-Van, Hiep; Koo, Insoo
2014-01-01
Energy resource management is a crucial problem of a device with a finite capacity battery. In this paper, cognitive radio is considered to be a device with an energy harvester that can harvest energy from a non-RF energy resource while performing other actions of cognitive radio. Harvested energy will be stored in a finite capacity battery. At the start of the time slot of cognitive radio, the radio needs to determine if it should remain silent or carry out spectrum sensing based on the idle probability of the primary user and the remaining energy in order to maximize the throughput of the cognitive radio system. In addition, optimal sensing energy and adaptive transmission power control are also investigated in this paper to effectively utilize the limited energy of cognitive radio. Finding an optimal approach is formulated as a partially observable Markov decision process. The simulation results show that the proposed optimal decision scheme outperforms the myopic scheme in which current throughput is only considered when making a decision. PMID:24574885
Integration and Optimization of Alternative Sources of Energy in a Remote Region
NASA Astrophysics Data System (ADS)
Berberi, Pellumb; Inodnorjani, Spiro; Aleti, Riza
2010-01-01
In a remote coastal region supply of energy from national grid is insufficient for a sustainable development. Integration and optimization of local alternative renewable energy sources is an optional solution of the problem. In this paper we have studied the energetic potential of local sources of renewable energy (water, solar, wind and biomass). A bottom-up energy system optimization model is proposed in order to support planning policies for promoting the use of renewable energy sources. A software, based on multiple factors and constrains analysis for optimization energy flow is proposed, which provides detailed information for exploitation each source of energy, power and heat generation, GHG emissions and end-use sectors. Economical analysis shows that with existing technologies both stand alone and regional facilities may be feasible. Improving specific legislation will foster investments from Central or Local Governments and also from individuals, private companies or small families. The study is carried on the frame work of a FP6 project "Integrated Renewable Energy System."
Optimizing Performance of a Thermal Energy Storage System
NASA Astrophysics Data System (ADS)
Subirats Soler, Monica
In this thesis, the problem of electricity demand shifting for the cooling needs of a large institution using a thermal energy storage (TES) tank is considered. The system is formed by electric chillers, cooling towers and a TES tank that can store energy for the cooling demand of most days, but not for the hottest ones. The goal is to supply all the cooling needed while minimizing the cost. This is done by shifting the cooling demand to night and early morning hours, when electricity is cheaper and due to lower temperatures, the chillers work more efficiently. This is all done with the help of the TES tank, that acts as a buffer storing chilled water. After a series of assumptions and simplifications, the cost function becomes convex and thus a minimum solution exists. However, from previous work only the chillers were considered, omitting the negative effect that other components of the system, such as cooling towers, had on the overall cost of operation. Using data from the operation of the power plant under real conditions, a method to model the whole system is presented in this thesis. In addition, the algorithm relied on the knowledge of an accurate prediction of the cooling demand, which obviously is not known in advance. A method to predict it starting from a forecasting of the temperature is presented. Finally, the algorithm can be easily modified to allow the imposition constraints that limit the maximum power use of chillers, during specific periods, in response to the overall needs of the micro-grid.
Optimal energy window selection of a CZT-based small-animal SPECT for quantitative accuracy
NASA Astrophysics Data System (ADS)
Park, Su-Jin; Yu, A. Ram; Choi, Yun Young; Kim, Kyeong Min; Kim, Hee-Joung
2015-05-01
Cadmium zinc telluride (CZT)-based small-animal single-photon emission computed tomography (SPECT) has desirable characteristics such as superior energy resolution, but data acquisition for SPECT imaging has been widely performed with a conventional energy window. The aim of this study was to determine the optimal energy window settings for technetium-99 m (99mTc) and thallium-201 (201Tl), the most commonly used isotopes in SPECT imaging, using CZT-based small-animal SPECT for quantitative accuracy. We experimentally investigated quantitative measurements with respect to primary count rate, contrast-to-noise ratio (CNR), and scatter fraction (SF) within various energy window settings using Triumph X-SPECT. The two ways of energy window settings were considered: an on-peak window and an off-peak window. In the on-peak window setting, energy centers were set on the photopeaks. In the off-peak window setting, the ratios of energy differences between the photopeak from the lower- and higher-threshold varied from 4:6 to 3:7. In addition, the energy-window width for 99mTc varied from 5% to 20%, and that for 201Tl varied from 10% to 30%. The results of this study enabled us to determine the optimal energy windows for each isotope in terms of primary count rate, CNR, and SF. We selected the optimal energy window that increases the primary count rate and CNR while decreasing SF. For 99mTc SPECT imaging, the energy window of 138-145 keV with a 5% width and off-peak ratio of 3:7 was determined to be the optimal energy window. For 201Tl SPECT imaging, the energy window of 64-85 keV with a 30% width and off-peak ratio of 3:7 was selected as the optimal energy window. Our results demonstrated that the proper energy window should be carefully chosen based on quantitative measurements in order to take advantage of desirable characteristics of CZT-based small-animal SPECT. These results provided valuable reference information for the establishment of new protocol for CZT
Zhao, Xiuli; Asante Antwi, Henry; Yiranbon, Ethel
2014-01-01
The idea of aggregating information is clearly recognizable in the daily lives of all entities whether as individuals or as a group, since time immemorial corporate organizations, governments, and individuals as economic agents aggregate information to formulate decisions. Energy planning represents an investment-decision problem where information needs to be aggregated from credible sources to predict both demand and supply of energy. To do this there are varying methods ranging from the use of portfolio theory to managing risk and maximizing portfolio performance under a variety of unpredictable economic outcomes. The future demand for energy and need to use solar energy in order to avoid future energy crisis in Jiangsu province in China require energy planners in the province to abandon their reliance on traditional, "least-cost," and stand-alone technology cost estimates and instead evaluate conventional and renewable energy supply on the basis of a hybrid of optimization models in order to ensure effective and reliable supply. Our task in this research is to propose measures towards addressing optimal solar energy forecasting by employing a systematic optimization approach based on a hybrid of weather and energy forecast models. After giving an overview of the sustainable energy issues in China, we have reviewed and classified the various models that existing studies have used to predict the influences of the weather influences and the output of solar energy production units. Further, we evaluate the performance of an exemplary ensemble model which combines the forecast output of two popular statistical prediction methods using a dynamic weighting factor. PMID:24511292
Zhao, Xiuli; Yiranbon, Ethel
2014-01-01
The idea of aggregating information is clearly recognizable in the daily lives of all entities whether as individuals or as a group, since time immemorial corporate organizations, governments, and individuals as economic agents aggregate information to formulate decisions. Energy planning represents an investment-decision problem where information needs to be aggregated from credible sources to predict both demand and supply of energy. To do this there are varying methods ranging from the use of portfolio theory to managing risk and maximizing portfolio performance under a variety of unpredictable economic outcomes. The future demand for energy and need to use solar energy in order to avoid future energy crisis in Jiangsu province in China require energy planners in the province to abandon their reliance on traditional, “least-cost,” and stand-alone technology cost estimates and instead evaluate conventional and renewable energy supply on the basis of a hybrid of optimization models in order to ensure effective and reliable supply. Our task in this research is to propose measures towards addressing optimal solar energy forecasting by employing a systematic optimization approach based on a hybrid of weather and energy forecast models. After giving an overview of the sustainable energy issues in China, we have reviewed and classified the various models that existing studies have used to predict the influences of the weather influences and the output of solar energy production units. Further, we evaluate the performance of an exemplary ensemble model which combines the forecast output of two popular statistical prediction methods using a dynamic weighting factor. PMID:24511292
Taxation and Sugar-Sweetened Beverages: Position of Dietitians of Canada.
2016-06-01
Dietitians of Canada recommends that an excise tax of at least 10-20% be applied to sugar-sweetened beverages sold in Canada given the negative impact of these products on the health of the population and the viability of taxation as a means to reduce consumption. For the greatest impact, taxation measures should be combined with other policy interventions such as increasing access to healthy foods while decreasing access to unhealthy foods in schools, daycares, and recreation facilities; restrictions on the marketing of foods and beverages to children; and effective, long-term educational initiatives. This position is based on a comprehensive review of the literature. The Canadian population is experiencing high rates of obesity and excess weight. There is moderate quality evidence linking consumption of sugar-sweetened beverages to excess weight, obesity, and chronic disease onset in children and adults. Taxation of sugar-sweetened beverages holds substantiated potential for decreasing its consumption. Based on economic models and results from recent taxation efforts, an excise tax can lead to a decline in sugar-sweetened beverage purchase and consumption. Taxation of up to 20% can lead to a consumption decrease by approximately 10% in the first year of its implementation, with a postulated 2.6% decrease in weight per person on average. Revenue generated from taxation can be used to fund other obesity reduction initiatives. A number of influential national organizations support a tax on sugar-sweetened beverages. PMID:27183052
An optimal operational advisory system for a brewery's energy supply plant
Ito, K.; Shiba, T.; Yokoyama, R. . Dept. of Energy Systems Engineering); Sakashita, S. . Mayekawa Energy Management Research Center)
1994-03-01
An optimal operational advisory system is proposed to operate rationally a brewery's energy supply plant from the economical viewpoint. A mixed-integer linear programming problem is formulated so as to minimize the daily operational cost subject to constraints such as equipment performance characteristics, energy supply-demand relations, and some practical operational restrictions. This problem includes lots of unknown variables and a hierarchical approach is adopted to derive numerical solutions. The optimal solution obtained by this methods is indicated to the plant operators so as to support their decision making. Through the numerical study for a real brewery plant, the possibility of saving operational cost is ascertained.
A modified method of vibration surveillance by using the optimal control at energy performance index
NASA Astrophysics Data System (ADS)
Kaliński, Krzysztof J.; Galewski, Marek A.
2015-06-01
A method of vibration surveillance by using the optimal control at energy performance index has been creatively modified. The suggested original modification depends on consideration of direct relationship between the measured acceleration signal and the optimal control command. The paper presents the results of experiments and Hardware-in-the-loop simulations of a new active vibration reduction algorithm based on the energy performance index idea modified in such a way, that it directly utilises the acceleration feedback signal. Promising prospects towards real application of the modified method in case of the high speed milling are predicted as well.
NASA Technical Reports Server (NTRS)
Nissim, E.; Abel, I.
1978-01-01
An optimization procedure is developed based on the responses of a system to continuous gust inputs. The procedure uses control law transfer functions which have been partially determined by using the relaxed aerodynamic energy approach. The optimization procedure yields a flutter suppression system which minimizes control surface activity in a gust environment. The procedure is applied to wing flutter of a drone aircraft to demonstrate a 44 percent increase in the basic wing flutter dynamic pressure. It is shown that a trailing edge control system suppresses the flutter instability over a wide range of subsonic mach numbers and flight altitudes. Results of this study confirm the effectiveness of the relaxed energy approach.
NASA Astrophysics Data System (ADS)
Mirab, Hadi; Fathi, Reza; Jahangiri, Vahid; Ettefagh, Mir Mohammad; Hassannejad, Reza
2015-12-01
One of the new methods for powering low-power electronic devices at sea is a wave energy harvesting system. In this method, piezoelectric material is employed to convert the mechanical energy of sea waves into electrical energy. The advantage of this method is based on avoiding a battery charging system. Studies have been done on energy harvesting from sea waves, however, considering energy harvesting with random JONSWAP wave theory, then determining the optimum values of energy harvested is new. This paper does that by implementing the JONSWAP wave model, calculating produced power, and realistically showing that output power is decreased in comparison with the more simple airy wave model. In addition, parameters of the energy harvester system are optimized using a simulated annealing algorithm, yielding increased produced power.
Energy-optimal electrical-stimulation pulses shaped by the Least-Action Principle.
Krouchev, Nedialko I; Danner, Simon M; Vinet, Alain; Rattay, Frank; Sawan, Mohamad
2014-01-01
Electrical stimulation (ES) devices interact with excitable neural tissue toward eliciting action potentials (AP's) by specific current patterns. Low-energy ES prevents tissue damage and loss of specificity. Hence to identify optimal stimulation-current waveforms is a relevant problem, whose solution may have significant impact on the related medical (e.g. minimized side-effects) and engineering (e.g. maximized battery-life) efficiency. This has typically been addressed by simulation (of a given excitable-tissue model) and iterative numerical optimization with hard discontinuous constraints--e.g. AP's are all-or-none phenomena. Such approach is computationally expensive, while the solution is uncertain--e.g. may converge to local-only energy-minima and be model-specific. We exploit the Least-Action Principle (LAP). First, we derive in closed form the general template of the membrane-potential's temporal trajectory, which minimizes the ES energy integral over time and over any space-clamp ionic current model. From the given model we then obtain the specific energy-efficient current waveform, which is demonstrated to be globally optimal. The solution is model-independent by construction. We illustrate the approach by a broad set of example situations with some of the most popular ionic current models from the literature. The proposed approach may result in the significant improvement of solution efficiency: cumbersome and uncertain iteration is replaced by a single quadrature of a system of ordinary differential equations. The approach is further validated by enabling a general comparison to the conventional simulation and optimization results from the literature, including one of our own, based on finite-horizon optimal control. Applying the LAP also resulted in a number of general ES optimality principles. One such succinct observation is that ES with long pulse durations is much more sensitive to the pulse's shape whereas a rectangular pulse is most frequently
Afshar, Puya; Brown, Martin; Maciejowski, Jan; Wang, Hong
2011-12-01
Reducing energy consumption is a major challenge for "energy-intensive" industries such as papermaking. A commercially viable energy saving solution is to employ data-based optimization techniques to obtain a set of "optimized" operational settings that satisfy certain performance indices. The difficulties of this are: 1) the problems of this type are inherently multicriteria in the sense that improving one performance index might result in compromising the other important measures; 2) practical systems often exhibit unknown complex dynamics and several interconnections which make the modeling task difficult; and 3) as the models are acquired from the existing historical data, they are valid only locally and extrapolations incorporate risk of increasing process variability. To overcome these difficulties, this paper presents a new decision support system for robust multiobjective optimization of interconnected processes. The plant is first divided into serially connected units to model the process, product quality, energy consumption, and corresponding uncertainty measures. Then multiobjective gradient descent algorithm is used to solve the problem in line with user's preference information. Finally, the optimization results are visualized for analysis and decision making. In practice, if further iterations of the optimization algorithm are considered, validity of the local models must be checked prior to proceeding to further iterations. The method is implemented by a MATLAB-based interactive tool DataExplorer supporting a range of data analysis, modeling, and multiobjective optimization techniques. The proposed approach was tested in two U.K.-based commercial paper mills where the aim was reducing steam consumption and increasing productivity while maintaining the product quality by optimization of vacuum pressures in forming and press sections. The experimental results demonstrate the effectiveness of the method. PMID:22147299
Energy-Optimal Electrical-Stimulation Pulses Shaped by the Least-Action Principle
Krouchev, Nedialko I.; Danner, Simon M.; Vinet, Alain; Rattay, Frank; Sawan, Mohamad
2014-01-01
Electrical stimulation (ES) devices interact with excitable neural tissue toward eliciting action potentials (AP’s) by specific current patterns. Low-energy ES prevents tissue damage and loss of specificity. Hence to identify optimal stimulation-current waveforms is a relevant problem, whose solution may have significant impact on the related medical (e.g. minimized side-effects) and engineering (e.g. maximized battery-life) efficiency. This has typically been addressed by simulation (of a given excitable-tissue model) and iterative numerical optimization with hard discontinuous constraints - e.g. AP’s are all-or-none phenomena. Such approach is computationally expensive, while the solution is uncertain - e.g. may converge to local-only energy-minima and be model-specific. We exploit the Least-Action Principle (LAP). First, we derive in closed form the general template of the membrane-potential’s temporal trajectory, which minimizes the ES energy integral over time and over any space-clamp ionic current model. From the given model we then obtain the specific energy-efficient current waveform, which is demonstrated to be globally optimal. The solution is model-independent by construction. We illustrate the approach by a broad set of example situations with some of the most popular ionic current models from the literature. The proposed approach may result in the significant improvement of solution efficiency: cumbersome and uncertain iteration is replaced by a single quadrature of a system of ordinary differential equations. The approach is further validated by enabling a general comparison to the conventional simulation and optimization results from the literature, including one of our own, based on finite-horizon optimal control. Applying the LAP also resulted in a number of general ES optimality principles. One such succinct observation is that ES with long pulse durations is much more sensitive to the pulse’s shape whereas a rectangular pulse is most
Multiphase Nano-Composite Coatings for Achieving Energy Optimization
Nainaparampil, Jose
2012-03-26
UES Inc. and ANL teamed in this work to develop novel coating systems for the protection of surfaces from thermal degradation mainly in two applications; Machining and Die casting. These coatings were specifically designed for the purpose by incorporating required material phases and the overall architecture, which led to reduce the energy usage and increase efficiency of the operations. Following the UES/ANL's feasibility work, the coatings were developed utilizing High power impulse magnetron sputtering (HiPMS) and Large area filtered arc deposition (LAFAD) techniques. Toughness, hardness and oxidation resistance: contrasting qualities have been mixed in the right proportion to attain the suitable material characteristic for the cause. Hafnium diboride (HfB2) based materials provided such a system and its properties were tamed to attain the right combination of toughness and hardness by working on the microstructure and architecture of coatings. An effective interfacing material (graded concentrations of topcoat) was also achieved in this work to provide the required adhesion between the substrate and the coating. Combination of an appropriate bond coat and a functional top coat provided the present thermal degradation resistant coating for cutting tools and die-casting applications. Laboratory level performance tests and industrial level application tests by partner companies (Beta Site Testing) were used for the development of these coatings.
Optimized growth of gold nanobars for energy responsive applications
NASA Astrophysics Data System (ADS)
Hobbs, Erik; Johnson, Anthony; Hart, Cacie; Schaefer, David; Kolagani, Rajeswari; Devadas, Mary Sajini
The aim of this research is to create a reliable protocol for the synthesis of plasmonic gold nano bars for energy responsive applications such as light harvesting. The mechanism of growth in these metallic structures is not fully understood. Symmetry breaking by twinning introduces anisotropy in the shape of the nanostructures. This also results in the formation of highly faceted tip geometries that support the propagation of surface plasmon polaritons. Gold nanobars have been synthesized through chemical reduction in the presence of surfactants: cetyltrimethylammonium bromide (CTAB) and polyvinylpyrrolidone (PVP). Synthesis is executed by varying the concentrations of CTAB and PVP, as well as adjusting the growth temperature. The influence of additives such as metal ions will be presented. Resulting plasmonic gold nanobars are viewed using darkfield microscopy and scanning electron microscopy to visualize the nanoparticle product mixture. Atomic force microscopy is employed to measure the length and width of the nanobelts. X-ray diffraction determines the degree of crystallinity in the synthesized gold nanobars.
Optimal Path to a Laser Fusion Energy Power Plant
NASA Astrophysics Data System (ADS)
Bodner, Stephen
2013-10-01
There was a decision in the mid 1990s to attempt ignition using indirect-drive targets. It is now obvious that this decision was unjustified. The target design was too geometrically complex, too inefficient, and too far above plasma instability thresholds. By that same time, the mid 1990s, there had also been major advances in the direct-drive target concept. It also was not yet ready for a major test. Now, finally, because of significant advances in target designs, laser-target experiments, and laser development, the direct-drive fusion concept is ready for significant enhancements in funding, on the path to commercial fusion energy. There are two laser contenders. A KrF laser is attractive because of its shortest wavelength, broad bandwidth, and superb beam uniformity. A frequency-converted DPSSL has the disadvantage of inherently narrow bandwidth and longer wavelength, but by combining many beams in parallel one might be able to produce at the target the equivalent of an ultra-broad bandwidth. One or both of these lasers may also meet all of the engineering and economic requirements for a reactor. It is time to further develop and evaluate these two lasers as rep-rate systems, in preparation for a future high-gain fusion test.
Optimization of intensity-modulated very high energy (50-250 MeV) electron therapy
NASA Astrophysics Data System (ADS)
Yeboah, C.; Sandison, G. A.; Moskvin, V.
2002-04-01
This work evaluates the potential of very high energy (50-250 MeV) electron beams for dose conformation and identifies those variables that influence optimized dose distributions for this modality. Intensity-modulated plans for a prostate cancer model were optimized as a function of the importance factors, beam energy and number of energy bins, number of beams, and the beam orientations. A trial-and-error-derived constellation of importance factors for target and sensitive structures to achieve good conformal dose distributions was 500, 50, 10 and 1 for the target, rectum, bladder and normal tissues respectively. Electron energies greater than 100 MeV were found to be desirable for intensity-modulated very high energy electron therapy (VHEET) of prostate cancer. Plans generated for lower energy beams had relatively poor conformal dose distributions about the target region and delivered high doses to sensitive structures. Fixed angle beam treatments utilizing a large number of fields in the range 9-21 provided acceptable plans. Using more than 21 beams at fixed gantry angles had an insignificant effect on target coverage, but resulted in an increased dose to sensitive structures and an increased normal tissue integral dose. Minor improvements in VHEET plans utilizing a `small' number (=<9) of beams may be achieved if, in addition to intensity modulation, energy modulation is implemented using a small number (=<3) of beam energies separated by 50 to 100 MeV. Rotation therapy provided better target dose homogeneity but unfortunately resulted in increased rectal dose, bladder dose and normal tissue integral dose relative to the 21-field fixed angle treatment plan. Modulation of the beam energy for rotation therapy had no beneficial consequences on the optimized dose distributions. Lastly, selection of beam orientations influenced the optimized treatment plan even when a large number of beams (approximately 15) were employed.
Assessment of grid-friendly collective optimization framework for distributed energy resources
Pensini, Alessandro; Robinson, Matthew; Heine, Nicholas; Stadler, Michael; Mammoli, Andrea
2015-11-04
Distributed energy resources have the potential to provide services to facilities and buildings at lower cost and environmental impact in comparison to traditional electric-gridonly services. The reduced cost could result from a combination of higher system efficiency and exploitation of electricity tariff structures. Traditionally, electricity tariffs are designed to encourage the use of ‘off peak’ power and discourage the use of ‘onpeak’ power, although recent developments in renewable energy resources and distributed generation systems (such as their increasing levels of penetration and their increased controllability) are resulting in pressures to adopt tariffs of increasing complexity. Independently of the tariff structure, more or less sophisticated methods exist that allow distributed energy resources to take advantage of such tariffs, ranging from simple pre-planned schedules to Software-as-a-Service schedule optimization tools. However, as the penetration of distributed energy resources increases, there is an increasing chance of a ‘tragedy of the commons’ mechanism taking place, where taking advantage of tariffs for local benefit can ultimately result in degradation of service and higher energy costs for all. In this work, we use a scheduling optimization tool, in combination with a power distribution system simulator, to investigate techniques that could mitigate the deleterious effect of ‘selfish’ optimization, so that the high-penetration use of distributed energy resources to reduce operating costs remains advantageous while the quality of service and overall energy cost to the community is not affected.
NASA Astrophysics Data System (ADS)
Ji, Xi; Chen, Zhanming; Li, Jinkai
2014-03-01
Cities are the main material processors associated with industrialization. The development of urban production based on fossil fuels is the major contributor to the rise of greenhouse gas density, and to global warming. The concept of urban industrial structure optimization is considered to be a solution to urban sustainable development and global climate issues. Enforcing energy conservation and reducing carbon emissions are playing key roles in addressing these issues. As such, quantitative accounting and the evaluation of energy consumption and corresponding carbon emissions, which are by-products of urban production, are critical, in order to discover potential opportunities to save energy and to reduce emissions. Conventional evaluation indicators, such as "energy consumption per unit output value" and "emissions per unit output value", are concerned with immediate consumptions and emissions; while the indirect consumptions and emissions that occur throughout the supply chain are ignored. This does not support the optimization of the overall urban industrial system. To present a systematic evaluation framework for cities, this study constructs new evaluation indicators, based on the concepts of "embodied energy" and "embodied carbon emissions", which take both the immediate and indirect effects of energy consumption and emissions into account. Taking Beijing as a case, conventional evaluation indicators are compared with the newly constructed ones. Results show that the energy consumption and emissions of urban industries are represented better by the new indicators than by conventional indicators, and provide useful information for urban industrial structure optimization.
ARRAY OPTIMIZATION FOR TIDAL ENERGY EXTRACTION IN A TIDAL CHANNEL – A NUMERICAL MODELING ANALYSIS
Yang, Zhaoqing; Wang, Taiping; Copping, Andrea
2014-04-18
This paper presents an application of a hydrodynamic model to simulate tidal energy extraction in a tidal dominated estuary in the Pacific Northwest coast. A series of numerical experiments were carried out to simulate tidal energy extraction with different turbine array configurations, including location, spacing and array size. Preliminary model results suggest that array optimization for tidal energy extraction in a real-world site is a very complex process that requires consideration of multiple factors. Numerical models can be used effectively to assist turbine siting and array arrangement in a tidal turbine farm for tidal energy extraction.
Not Available
1980-08-01
These proceedings document the presentations given at the Energy Optimization of Water and Wastewater Management for Municipal and Industrial Applications Conference, sponsored by the Department of Energy (DOE). The conference was organized and coordinated by Argonne National Laboratory. The conference focused on energy use and conservation in water and wastewater. The General Session also reflects DOE's commitment to the support and development of waste and wastewater systems that are environmentally acceptable. The conference proceedings are divided into two volumes. Volume 1 contains the General Session and Sessions 1 to 5. Volume 2 covers Sessions 6 to 12. Separate abstracts are prepared for each item within the scope of the Energy Data Base.
Kydes, A S
1980-11-01
The Brookhaven Energy System Optimization Model (BESOM), three of its variants, and two examples of characteristic applications are described. BESOM is a linear-programming model that was developed for the quantitative evaluation of energy technologies and policies within a systems framework. The model is designed to examine interfuel substitutions in the context of constraints on the availability of competing resources and technologies. BESOM provides a snapshot of the national energy system configuration, while MARKAL and TESOM provide, respectively, a farsighted time dimension and a simulation capability for the examination of the evolution of a national energy system over a time horizon.
Not Available
1980-08-01
These proceedings document the presentations given at the Energy Optimization of Water and Wastewater Management for Municipal and Industrial Applications, Conference, sponsored by the Department of Energy (DOE). The conference was organized and coordinated by Argonne National Laboratory. The conference focused on energy use on conservation in water and wastewater. The General Session also reflects DOE's commitment to the support and development of waste and wastewater systems that are environmentally acceptable. The conference proceedings are divided into two volumes. Volume 1 contains the General Session and Sessions 1 to 5. Volume 2 covers Sessions 6 to 12. Separate abstracts are prepared for each item within the scope of the Energy Data Base.
Energy management of three-dimensional minimum-time intercept. [for aircraft flight optimization
NASA Technical Reports Server (NTRS)
Kelley, H. J.; Cliff, E. M.; Visser, H. G.
1985-01-01
A real-time computer algorithm to control and optimize aircraft flight profiles is described and applied to a three-dimensional minimum-time intercept mission. The proposed scheme has roots in two well known techniques: singular perturbations and neighboring-optimal guidance. Use of singular-perturbation ideas is made in terms of the assumed trajectory-family structure. A heading/energy family of prestored point-mass-model state-Euler solutions is used as the baseline in this scheme. The next step is to generate a near-optimal guidance law that will transfer the aircraft to the vicinity of this reference family. The control commands fed to the autopilot (bank angle and load factor) consist of the reference controls plus correction terms which are linear combinations of the altitude and path-angle deviations from reference values, weighted by a set of precalculated gains. In this respect the proposed scheme resembles neighboring-optimal guidance. However, in contrast to the neighboring-optimal guidance scheme, the reference control and state variables as well as the feedback gains are stored as functions of energy and heading in the present approach. Some numerical results comparing open-loop optimal and approximate feedback solutions are presented.
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.
On Maximizing the Lifetime of Wireless Sensor Networks by Optimally Assigning Energy Supplies
Asorey-Cacheda, Rafael; García-Sánchez, Antonio Javier; García-Sánchez, Felipe; García-Haro, Joan; Gonzalez-Castaño, Francisco Javier
2013-01-01
The extension of the network lifetime of Wireless Sensor Networks (WSN) is an important issue that has not been appropriately solved yet. This paper addresses this concern and proposes some techniques to plan an arbitrary WSN. To this end, we suggest a hierarchical network architecture, similar to realistic scenarios, where nodes with renewable energy sources (denoted as primary nodes) carry out most message delivery tasks, and nodes equipped with conventional chemical batteries (denoted as secondary nodes) are those with less communication demands. The key design issue of this network architecture is the development of a new optimization framework to calculate the optimal assignment of renewable energy supplies (primary node assignment) to maximize network lifetime, obtaining the minimum number of energy supplies and their node assignment. We also conduct a second optimization step to additionally minimize the number of packet hops between the source and the sink. In this work, we present an algorithm that approaches the results of the optimization framework, but with much faster execution speed, which is a good alternative for large-scale WSN networks. Finally, the network model, the optimization process and the designed algorithm are further evaluated and validated by means of computer simulation under realistic conditions. The results obtained are discussed comparatively. PMID:23939582
Design and optimization of a large flow rate booster pump in SWRO energy recovery system
NASA Astrophysics Data System (ADS)
Lai, Z. N.; Wu, P.; Wu, D. Z.; Wang, L. Q.
2013-12-01
Seawater reverse osmosis (SWRO) is a high energy-consumption industry, so energy efficiency is an important issue. Energy recovery systems, which contain a pressure exchanger and a booster pump, are widely used in SWRO plants. As a key part of energy recovery system, the difficulty of designing booster pumps lies in high inlet pressure, high medium causticity and large flow rate. High inlet pressure adds difficulties to seal design, and large flow rate and high efficiency requirement bring high demand for hydraulic design. In this paper, a 625 m3/h booster pump is designed and optimized according to the CFD (Computational Fluid Dynamics) simulation results. The impeller and volute is well designed, a new type of high pressure mechanical seal is applied and axial force is well balanced. After optimization based on blade redesign, the efficiency of the pump was improved. The best efficiency reaches more than 85% at design point according to the CFD simulation result.
Neubauer, J.; Simpson, M.
2013-10-01
Commercial facility utility bills are often a strong function of demand charges -- a fee proportional to peak power demand rather than total energy consumed. In some instances, demand charges can constitute more than 50% of a commercial customer's monthly electricity cost. While installation of behind-the-meter solar power generation decreases energy costs, its variability makes it likely to leave the peak load -- and thereby demand charges -- unaffected. This then makes demand charges an even larger fraction of remaining electricity costs. Adding controllable behind-the-meter energy storage can more predictably affect building peak demand, thus reducing electricity costs. Due to the high cost of energy storage technology, the size and operation of an energy storage system providing demand charge management (DCM) service must be optimized to yield a positive return on investment (ROI). The peak demand reduction achievable with an energy storage system depends heavily on a facility's load profile, so the optimal configuration will be specific to both the customer and the amount of installed solar power capacity. We explore the sensitivity of DCM value to the power and energy levels of installed solar power and energy storage systems. An optimal peak load reduction control algorithm for energy storage systems will be introduced and applied to historic solar power data and meter load data from multiple facilities for a broad range of energy storage system configurations. For each scenario, the peak load reduction and electricity cost savings will be computed. From this, we will identify a favorable energy storage system configuration that maximizes ROI.
Energy and delay trade-offs in arithmetic circuits: Methodologies and optimizations
NASA Astrophysics Data System (ADS)
Baran, Dursun
Technology scaling cannot provide sufficient amount of energy reduction to keep control of the energy consumption of the current VLSI systems. In order to solve the problem of the high power dissipation of current processors, a complete optimization framework is developed. The system architecture, circuit topology, gate sizes and the technology related parameters are optimized jointly. For this purpose, circuit design methodologies are developed for demanded applications. The developed circuit design techniques target two objectives namely critical path complexity reduction of the circuit and the equalization of the signal path complexities. The generated circuit topologies are candidates for the energy efficient design. The final determination of the best circuit topology is made after optimizing the gate sizes and the voltage supply of the design. For this purpose, a quick circuit sizing algorithm (Constant Stage Effort Ratio) is developed. The algorithm redistributes the effort delay through the circuit to reduce the energy consumption at the same performance. The run-time of the developed algorithm linearly depends on the number of the logic gates in the circuit. By using the developed algorithm, a considerable amount of the run-time improvement is obtained. The developed optimization framework is applied to the parallel prefix adders and parallel multipliers. Up to 4.5X energy saving is obtained by the use of the design methodologies in 64-bit parallel adders over existing designs. Energy-efficient parallel adder structures are developed for static, domino and compound domino logic families. The suitability of the developed design techniques are explored in future technology nodes as well. Similar analysis is performed to the parallel multipliers. 16x16-bit serial, single-cycle parallel and two-cycle parallel multiplier structures are optimized using the developed optimization flow. Up to 20% energy reduction is obtained in static single-cycle 16x16-bit
NASA Astrophysics Data System (ADS)
Zhou, Junle; Chen, Lingen; Ding, Zemin; Sun, Fengrui
2016-05-01
Applying finite-time thermodynamics (FTT) and electronic transport theory, the optimal performances of irreversible single resonance energy selective electron (ESE) refrigerator are analyzed. The effects of heat leakage between two electron reservoirs on optimal performances are discussed. The influences of system operating parameters on cooling load, coefficient of performance (COP), figure of merit and ecological function are demonstrated using numerical examples. Comparative performance analyses among different objective functions show that performance characteristics at maximum ecological function and maximum figure of merit are of great practical significance. Combining the two optimization objectives of maximum ecological function and maximum figure of merit together, more specific optimal ranges of cooling load and COP are obtained. The results can provide some advices to the design of practical electronic machine systems.
Yu, Jia; Yu, Zhichao; Tang, Chenlong
2016-01-01
The hot work environment of electronic components in the instrument cabin of spacecraft was researched, and a new thermal protection structure, namely graphite carbon foam, which is an impregnated phase-transition material, was adopted to implement the thermal control on the electronic components. We used the optimized parameters obtained from ANSYS to conduct 2D optimization, 3-D modeling and simulation, as well as the strength check. Finally, the optimization results were verified by experiments. The results showed that after optimization, the structured carbon-based energy-storing composite material could reduce the mass and realize the thermal control over electronic components. This phase-transition composite material still possesses excellent temperature control performance after its repeated melting and solidifying. PMID:27387673
Improvement of the energy resolution via an optimized digital signal processing in GERDA Phase I
NASA Astrophysics Data System (ADS)
Agostini, M.; Allardt, M.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Barros, N.; Baudis, L.; Bauer, C.; Becerici-Schmidt, N.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode, T.; Borowicz, D.; Brudanin, V.; Brugnera, R.; Budjáš, D.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; D'Andrea, V.; Demidova, E. V.; Vacri, A. di; Domula, A.; Doroshkevich, E.; Egorov, V.; Falkenstein, R.; Fedorova, O.; Freund, K.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Hegai, A.; Heisel, M.; Hemmer, S.; Heusser, G.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Janicskó Csáthy, J.; Jochum, J.; Junker, M.; Kazalov, V.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Klimenko, A.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, ********************M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Majorovits, B.; Maneschg, W.; Medinaceli, E.; Misiaszek, M.; Moseev, P.; Nemchenok, I.; Palioselitis, D.; Panas, K.; Pandola, L.; Pelczar, K.; Pullia, A.; Riboldi, S.; Rumyantseva, N.; Sada, C.; Salathe, M.; Schmitt, C.; Schneider, B.; Schönert, S.; Schreiner, J.; Schütz, A.-K.; Schulz, O.; Schwingenheuer, B.; Selivanenko, O.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Stepaniuk, M.; Ur, C. A.; Vanhoefer, L.; Vasenko, A. A.; Veresnikova, A.; von Sturm, K.; Wagner, V.; Walter, M.; Wegmann, A.; Wester, T.; Wilsenach, H.; Wojcik, M.; Yanovich, E.; Zavarise, P.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.
2015-06-01
An optimized digital shaping filter has been developed for the Gerda experiment which searches for neutrinoless double beta decay in Ge. The Gerda Phase I energy calibration data have been reprocessed and an average improvement of 0.3 keV in energy resolution (FWHM) corresponding to 10 % at the value for decay in Ge is obtained. This is possible thanks to the enhanced low-frequency noise rejection of this Zero Area Cusp (ZAC) signal shaping filter.
Singha, S.; Kumar, S.; Dey, S. K.
2015-06-24
Single crystal of a multicomponent salt (IMTBTP) of imidazole with tetrabromoterepthalic acid has been synthesized by slow evaporation method at room temperature. The crystal structure of the salt has been determined by single crystal x-ray diffraction technique. The supramolecular structure analysis reveals that the multicomponent salt is formed by noncovalent hydrogen bonding interaction and Br···π interaction. The energy optimization and HOMO-LUMO energy gap calculation have been carried out by Density Functional Theory.
Optimal Model of Distributed Energy System by Using GAMS and CaseStudy
Yang, Yongwen; Gao, Weijun; Ruan, Yingjun; Xuan, Ji; Zhou, Nan; Marnay, Chris
2005-11-30
This paper adopts optimal model which used GAMS to developmethods and tools for conducting an integrated assessment of DER system.Three cases were studied. Energy-saving, environmental and economicefficiency were evaluated. The results of the simulation can besummarized as follows: 1) For the current system, optimal operating timeis about 4,132 hours per year, and from 8 am to 22 pm everyday. 2) It iseconomical when electricity price increases or gas price decreases. 3)According to the load function of system, energy-saving, environmentaland economic efficiency will have amaximum value at optimal operatingtime. 4) Compared with exhaust heat efficiency, power generationefficiency has more influence to the economic efficiency and CO2reduction when the total efficiency is fixed.
Optimization of a microfluidic based electromagnetic energy harvester for shoe insoles
NASA Astrophysics Data System (ADS)
Rahman, M. M.; Atkin, R.; Kim, H.
2015-12-01
This paper reports improved performance of the 4th generation microfluidic based energy harvester by finding global optimization among various geometric parameters, resulting in the increase of power density by 6.89 times. Specifically, the power output was optimized by varying diameters and spans of a coil at different frequencies. To verify the optimization, a custom testing platform was constructed, which mimicked the periodic linear movement caused by a human foot. The final device produced total power of 455.77mW from a volume of 20×3.74×0.75cm3, resulting in a power density of 8.13mW/cm3 that was identified as one of the highest power densities among human-body-induced vibration based energy harvesters.
Energy simulation and optimization for a small commercial building through Modelica
NASA Astrophysics Data System (ADS)
Rivas, Bryan
Small commercial buildings make up the majority of buildings in the United States. Energy consumed by these buildings is expected to drastically increase in the next few decades, with a large percentage of the energy consumed attributed to cooling systems. This work presents the simulation and optimization of a thermostat schedule to minimize energy consumption in a small commercial building test bed during the cooling season. The simulation occurs through the use of the multi-engineering domain Dymola environment based on the Modelica open source programming language and is optimized with the Java based optimization program GenOpt. The simulation uses both physically based modeling utilizing heat transfer principles for the building and regression analysis for energy consumption. GenOpt is dynamically coupled to Dymola through various interface files. There are very few studies that have coupled GenOpt to a building simulation program and even fewer studies have used Dymola for building simulation as extensively as the work presented here. The work presented proves Dymola as a viable alternative to other building simulation programs such as EnergyPlus and MatLab. The model developed is used to simulate the energy consumption of a test bed, a commissioned real world small commercial building, while maintaining indoor thermal comfort. Potential applications include smart or intelligent building systems, predictive simulation of small commercial buildings, and building diagnostics.
NASA Astrophysics Data System (ADS)
Ibanez, Eduardo
Most U.S. energy usage is for electricity production and vehicle transportation, two interdependent infrastructures. The strength and number of the interdependencies will increase rapidly as hybrid electric transportation systems, including plug-in hybrid electric vehicles and hybrid electric trains, become more prominent. There are several new energy supply technologies reaching maturity, accelerated by public concern over global warming. The National Energy and Transportation Planning Tool (NETPLAN) is the implementation of the long-term investment and operation model for the transportation and energy networks. An evolutionary approach with underlying fast linear optimization are in place to determine the solutions with the best investment portfolios in terms of cost, resiliency and sustainability, i.e., the solutions that form the Pareto front. The popular NSGA-II algorithm is used as the base for the multiobjective optimization and metrics are developed for to evaluate the energy and transportation portfolios. An integrating approach to resiliency is presented, allowing the evaluation of high-consequence events, like hurricanes or widespread blackouts. A scheme to parallelize the multiobjective solver is presented, along with a decomposition method for the cost minimization program. The modular and data-driven design of the software is presented. The modeling tool is applied in a numerical example to optimize the national investment in energy and transportation in the next 40 years.
NASA Astrophysics Data System (ADS)
Escriva-Bou, A.; Lund, J. R.; Pulido-Velazquez, M.; Spang, E. S.; Loge, F. J.
2014-12-01
Although most freshwater resources are used in agriculture, a greater amount of energy is consumed per unit of water supply for urban areas. Therefore, efforts to reduce the carbon footprint of water in cities, including the energy embedded within household uses, can be an order of magnitude larger than for other water uses. This characteristic of urban water systems creates a promising opportunity to reduce global greenhouse gas emissions, particularly given rapidly growing urbanization worldwide. Based on a previous Water-Energy-CO2 emissions model for household water end uses, this research introduces a probabilistic two-stage optimization model considering technical and behavioral decision variables to obtain the most economical strategies to minimize household water and water-related energy bills given both water and energy price shocks. Results show that adoption rates to reduce energy intensive appliances increase significantly, resulting in an overall 20% growth in indoor water conservation if household dwellers include the energy cost of their water use. To analyze the consequences on a utility-scale, we develop an hourly water-energy model based on data from East Bay Municipal Utility District in California, including the residential consumption, obtaining that water end uses accounts for roughly 90% of total water-related energy, but the 10% that is managed by the utility is worth over 12 million annually. Once the entire end-use + utility model is completed, several demand-side management conservation strategies were simulated for the city of San Ramon. In this smaller water district, roughly 5% of total EBMUD water use, we found that the optimal household strategies can reduce total GHG emissions by 4% and utility's energy cost over 70,000/yr. Especially interesting from the utility perspective could be the "smoothing" of water use peaks by avoiding daytime irrigation that among other benefits might reduce utility energy costs by 0.5% according to our
Band-pass design optimization of piezoelectric cantilever bimorph energy harvester
NASA Astrophysics Data System (ADS)
Zhang, Long; Williams, Keith A.
2011-03-01
Piezoelectric energy harvesting has become a feasible method for powering micro portable electronics and wireless sensor networks by converting ambient vibration energy into electrical energy. As a thumb of rule, it is critical to tune the resonant frequency of the generator to the frequency of the environmental vibrations in order to induce the maximum structural deformation and then the maximum converted electrical energy through piezoelectric effect. However, it is well-known that the ambient vibrations are not usually fixed in only one single frequency and could span over a limited frequency band. In this paper, a band-pass design optimization of piezoelectric cantilever bimorph (PCB) energy harvester is presented based on the system transfer function of the PCB generator presented in a previous literature. For such an energy harvester, a group of PCB with dimensions appropriately selected can be integrated into a band-pass energy harvester working over a limited frequency band if the dimensions of piezoelectric bimorphs and proof masses are appropriately chosen. Further, the finite element analysis (FEA) of such a band-pass energy harvester is performed in ANSYS to validate the theoretical proposal. The result shows that the band-pass design optimization leads to a piezoelectric generator working over a certain frequency band while keeping outputting the relatively stable open-circuit voltage.
Optimization Based Data Mining Approah for Forecasting Real-Time Energy Demand
Omitaomu, Olufemi A; Li, Xueping; Zhou, Shengchao
2015-01-01
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 provided 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.
Larson, Kyle B.; Tagestad, Jerry D.; Perkins, Casey J.; Oster, Matthew R.; Warwick, M.; Geerlofs, Simon H.
2015-09-01
This study was conducted with the support of the U.S. Department of Energy’s (DOE’s) Wind and Water Power Technologies Office (WWPTO) as part of ongoing efforts to minimize key risks and reduce the cost and time associated with permitting and deploying ocean renewable energy. The focus of the study was to discuss a possible approach to exploring scenarios for ocean renewable energy development in Hawaii that attempts to optimize future development based on technical, economic, and policy criteria. The goal of the study was not to identify potentially suitable or feasible locations for development, but to discuss how such an approach may be developed for a given offshore area. Hawaii was selected for this case study due to the complex nature of the energy climate there and DOE’s ongoing involvement to support marine spatial planning for the West Coast. Primary objectives of the study included 1) discussing the political and economic context for ocean renewable energy development in Hawaii, especially with respect to how inter-island transmission may affect the future of renewable energy development in Hawaii; 2) applying a Geographic Information System (GIS) approach that has been used to assess the technical suitability of offshore renewable energy technologies in Washington, Oregon, and California, to Hawaii’s offshore environment; and 3) formulate a mathematical model for exploring scenarios for ocean renewable energy development in Hawaii that seeks to optimize technical and economic suitability within the context of Hawaii’s existing energy policy and planning.
Optimizing Distributed Energy Resources and building retrofits with the strategic DER-CAModel
Stadler, M.; Groissböck, M.; Cardoso, G.; Marnay, C.
2014-08-05
The pressuring need to reduce the import of fossil fuels as well as the need to dramatically reduce CO2 emissions in Europe motivated the European Commission (EC) to implement several regulations directed to building owners. Most of these regulations focus on increasing the number of energy efficient buildings, both new and retrofitted, since retrofits play an important role in energy efficiency. Overall, this initiative results from the realization that buildings will have a significant impact in fulfilling the 20/20/20-goals of reducing the greenhouse gas emissions by 20%, increasing energy efficiency by 20%, and increasing the share of renewables to 20%,more » all by 2020. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an optimization tool used to support DER investment decisions, typically by minimizing total annual costs or CO2 emissions while providing energy services to a given building or microgrid site. This document shows enhancements made to DER-CAM to consider building retrofit measures along with DER investment options. Specifically, building shell improvement options have been added to DER-CAM as alternative or complementary options to investments in other DER such as PV, solar thermal, combined heat and power, or energy storage. The extension of the mathematical formulation required by the new features introduced in DER-CAM is presented and the resulting model is demonstrated at an Austrian Campus building by comparing DER-CAM results with and without building shell improvement options. Strategic investment results are presented and compared to the observed investment decision at the test site. Results obtained considering building shell improvement options suggest an optimal weighted average U value of about 0.53 W/(m2K) for the test site. This result is approximately 25% higher than what is currently observed in the building, suggesting that the retrofits made in 2002 were not optimal. Furthermore, the results obtained with
Optimizing Distributed Energy Resources and building retrofits with the strategic DER-CAModel
Stadler, M.; Groissböck, M.; Cardoso, G.; Marnay, C.
2014-08-05
The pressuring need to reduce the import of fossil fuels as well as the need to dramatically reduce CO_{2} emissions in Europe motivated the European Commission (EC) to implement several regulations directed to building owners. Most of these regulations focus on increasing the number of energy efficient buildings, both new and retrofitted, since retrofits play an important role in energy efficiency. Overall, this initiative results from the realization that buildings will have a significant impact in fulfilling the 20/20/20-goals of reducing the greenhouse gas emissions by 20%, increasing energy efficiency by 20%, and increasing the share of renewables to 20%, all by 2020. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an optimization tool used to support DER investment decisions, typically by minimizing total annual costs or CO_{2} emissions while providing energy services to a given building or microgrid site. This document shows enhancements made to DER-CAM to consider building retrofit measures along with DER investment options. Specifically, building shell improvement options have been added to DER-CAM as alternative or complementary options to investments in other DER such as PV, solar thermal, combined heat and power, or energy storage. The extension of the mathematical formulation required by the new features introduced in DER-CAM is presented and the resulting model is demonstrated at an Austrian Campus building by comparing DER-CAM results with and without building shell improvement options. Strategic investment results are presented and compared to the observed investment decision at the test site. Results obtained considering building shell improvement options suggest an optimal weighted average U value of about 0.53 W/(m^{2}K) for the test site. This result is approximately 25% higher than what is currently observed in the building, suggesting that the retrofits made in 2002 were not optimal. Furthermore
The use of least squares methods in functional optimization of energy use prediction models
NASA Astrophysics Data System (ADS)
Bourisli, Raed I.; Al-Shammeri, Basma S.; AlAnzi, Adnan A.
2012-06-01
The least squares method (LSM) is used to optimize the coefficients of a closed-form correlation that predicts the annual energy use of buildings based on key envelope design and thermal parameters. Specifically, annual energy use is related to a number parameters like the overall heat transfer coefficients of the wall, roof and glazing, glazing percentage, and building surface area. The building used as a case study is a previously energy-audited mosque in a suburb of Kuwait City, Kuwait. Energy audit results are used to fine-tune the base case mosque model in the VisualDOE{trade mark, serif} software. Subsequently, 1625 different cases of mosques with varying parameters were developed and simulated in order to provide the training data sets for the LSM optimizer. Coefficients of the proposed correlation are then optimized using multivariate least squares analysis. The objective is to minimize the difference between the correlation-predicted results and the VisualDOE-simulation results. It was found that the resulting correlation is able to come up with coefficients for the proposed correlation that reduce the difference between the simulated and predicted results to about 0.81%. In terms of the effects of the various parameters, the newly-defined weighted surface area parameter was found to have the greatest effect on the normalized annual energy use. Insulating the roofs and walls also had a major effect on the building energy use. The proposed correlation and methodology can be used during preliminary design stages to inexpensively assess the impacts of various design variables on the expected energy use. On the other hand, the method can also be used by municipality officials and planners as a tool for recommending energy conservation measures and fine-tuning energy codes.
Model of a single mode energy harvester and properties for optimal power generation
NASA Astrophysics Data System (ADS)
Liao, Yabin; Sodano, Henry A.
2008-12-01
The process of acquiring the energy surrounding a system and converting it into usable electrical energy is termed power harvesting. In the last few years, the field of power harvesting has experienced significant growth due to the ever increasing desire to produce portable and wireless electronics with extended life. Current portable and wireless devices must be designed to include electrochemical batteries as the power source. The use of batteries can be troublesome due to their finite energy supply, which necessitates their periodic replacement. In the case of wireless sensors that are to be placed in remote locations, the sensor must be easily accessible or of disposable nature to allow the device to function over extended periods of time. Energy scavenging devices are designed to capture the ambient energy surrounding the electronics and covert it into usable electrical energy. The concept of power harvesting works towards developing self-powered devices that do not require replaceable power supplies. The development of energy harvesting systems is greatly facilitated by an accurate model to assist in the design of the system. This paper will describe a theoretical model of a piezoelectric based energy harvesting system that is simple to apply yet provides an accurate prediction of the power generated around a single mode of vibration. Furthermore, this model will allow optimization of system parameters to be studied such that maximal performance can be achieved. Using this model an expression for the optimal resistance and a parameter describing the energy harvesting efficiency will be presented and evaluated through numerical simulations. The second part of this paper will present an experimental validation of the model and optimal parameters.
NASA Astrophysics Data System (ADS)
Lebreton, J. M.; Murad, N. M.
2014-10-01
The purpose of this paper is to propose a method of energy distribution on a Wireless Sensor Network (WSN). Nodes are randomly positioned and the sink is placed at the centre of the surface. Simulations show that relay nodes around the sink are too much requested to convey data, which substantially reduces their lifetime. So, several algorithmic solutions are presented to optimize the energy distribution on each node, compared to the classical uniform energy distribution. Their performance is discussed in terms of failure rate of data transmission and network lifetime. Moreover, the total energy distributed on all nodes before the deployment is invariable and some non-uniform energy distributions are created. Finally, simulations show that every energy distributions greatly improve the WSN lifetime and decrease the failure rate of data transmission.
NASA Astrophysics Data System (ADS)
Zhang, Chi; Liu, Li-Wei; Wang, Long-Fei; Yue, Yuan; Yu, Lian-Chun
2015-11-01
Energy efficiency is closely related to the evolution of biological systems and is important to their information processing. In this paper, we calculated the excitation probability of a simple model of a bistable biological unit in response to pulsatile inputs, and its spontaneous excitation rate due to noise perturbation. Then we analytically calculated the mutual information, energy cost, and energy efficiency of an array of these bistable units. We found that the optimal number of units could maximize this array's energy efficiency in encoding pulse inputs, which depends on the fixed energy cost. We conclude that demand for energy efficiency in biological systems may strongly influence the size of these systems under the pressure of natural selection.
NASA Astrophysics Data System (ADS)
Wu, Jianlan; Liu, Fan; Shen, Young; Cao, Jianshu; Silbey, Robert J.
2010-10-01
Understanding the mechanisms of efficient and robust energy transfer in light-harvesting systems provides new insights for the optimal design of artificial systems. In this paper, we use the Fenna-Matthews-Olson (FMO) protein complex and phycocyanin 645 (PC 645) to explore the general dependence on physical parameters that help maximize the efficiency and maintain its stability. With the Haken-Strobl model, the maximal energy transfer efficiency (ETE) is achieved under an intermediate optimal value of dephasing rate. To avoid the infinite temperature assumption in the Haken-Strobl model and the failure of the Redfield equation in predicting the Forster rate behavior, we use the generalized Bloch-Redfield (GBR) equation approach to correctly describe dissipative exciton dynamics, and we find that maximal ETE can be achieved under various physical conditions, including temperature, reorganization energy and spatial-temporal correlations in noise. We also identify regimes of reorganization energy where the ETE changes monotonically with temperature or spatial correlation and therefore cannot be optimized with respect to these two variables.
Evolutionary techniques for sensor networks energy optimization in marine environmental monitoring
NASA Astrophysics Data System (ADS)
Grimaccia, Francesco; Johnstone, Ron; Mussetta, Marco; Pirisi, Andrea; Zich, Riccardo E.
2012-10-01
The sustainable management of coastal and offshore ecosystems, such as for example coral reef environments, requires the collection of accurate data across various temporal and spatial scales. Accordingly, monitoring systems are seen as central tools for ecosystem-based environmental management, helping on one hand to accurately describe the water column and substrate biophysical properties, and on the other hand to correctly steer sustainability policies by providing timely and useful information to decision-makers. A robust and intelligent sensor network that can adjust and be adapted to different and changing environmental or management demands would revolutionize our capacity to wove accurately model, predict, and manage human impacts on our coastal, marine, and other similar environments. In this paper advanced evolutionary techniques are applied to optimize the design of an innovative energy harvesting device for marine applications. The authors implement an enhanced technique in order to exploit in the most effective way the uniqueness and peculiarities of two classical optimization approaches, Particle Swarm Optimization and Genetic Algorithms. Here, this hybrid procedure is applied to a power buoy designed for marine environmental monitoring applications in order to optimize the recovered energy from sea-wave, by selecting the optimal device configuration.
NASA Astrophysics Data System (ADS)
Truong, Binh Duc; Phu Le, Cuong; Halvorsen, Einar
2015-12-01
This paper presents experiments on how to approach the physical limits on power from vibration energy harvesting under displacement-constrained operation. A MEMS electrostatic vibration energy harvester with voltage-control of the system stiffness is used for this purpose. The power saturation problem, when the proof mass displacement reaches maximum amplitude for sufficient acceleration amplitude, is shifted to higher accelerations by use of load optimization and tunable electromechanical coupling k2. Measurement results show that harvested power can be made to follow the optimal velocity-damped generator also for a range of accelerations that implies displacement constraints. Comparing to the saturated power, the power increases 1.5 times with the optimal load and an electromechanical coupling k2=8.7%. This value is 2.3 times for a higher coupling k2=17.9%. The obtained system effectiveness is beyond 60% under the optimization. This work also shows a first demonstration of reaching optimal power in the intermediate acceleration-range between the two extremes of maximum efficiency and maximum power transfer.
BEopt(TM) Software for Building Energy Optimization: Features and Capabilities
Christensen, C.; Anderson, R.; Horowitz, S.; Courtney, A.; Spencer, J.
2006-08-01
BEopt is a computer program designed to find optimal building designs along the path to ZNE. A user selects from predefined options in various categories to specify options to be considered in the optimization. Energy savings are calculated relative to a reference. The reference can be either a user-defined base-case building or a climate-specific Building America Benchmark building automatically generated by BEopt. The user can also review and modify detailed information on all available options in a linked options library spreadsheet. BEopt calls the DOE2 and TRNSYS simulation engines and uses a sequential search technique to automate the process of identifying optimal building designs along the path to ZNE. BEopt finds these optimal and near-optimal designs based on discrete building options reflecting realistic construction options. BEopt handles special situations with positive or negative interactions between options in different categories. The BEopt software includes a results browser that allows the user to navigate among different design points and retrieve detailed results regarding energy end-use and option costs in different categories. Multiple cases, based on a selected parameter such as climate, can be included in a BEopt project file for comparative purposes.
A system-level cost-of-energy wind farm layout optimization with landowner modeling
Chen, Le; MacDonald, Erin
2013-10-01
This work applies an enhanced levelized wind farm cost model, including landowner remittance fees, to determine optimal turbine placements under three landowner participation scenarios and two land-plot shapes. Instead of assuming a continuous piece of land is available for the wind farm construction, as in most layout optimizations, the problem formulation represents landowner participation scenarios as a binary string variable, along with the number of turbines. The cost parameters and model are a combination of models from the National Renewable Energy Laboratory (NREL), Lawrence Berkeley National Laboratory, and Windustiy. The system-level cost-of-energy (COE) optimization model is also tested under two land-plot shapes: equally-sized square land plots and unequal rectangle land plots. The optimal COEs results are compared to actual COE data and found to be realistic. The results show that landowner remittances account for approximately 10% of farm operating costs across all cases. Irregular land-plot shapes are easily handled by the model. We find that larger land plots do not necessarily receive higher remittance fees. The model can help site developers identify the most crucial land plots for project success and the optimal positions of turbines, with realistic estimates of costs and profitability. (C) 2013 Elsevier Ltd. All rights reserved.
Cross-layer Energy Optimization Under Image Quality Constraints for Wireless Image Transmissions.
Yang, Na; Demirkol, Ilker; Heinzelman, Wendi
2012-01-01
Wireless image transmission is critical in many applications, such as surveillance and environment monitoring. In order to make the best use of the limited energy of the battery-operated cameras, while satisfying the application-level image quality constraints, cross-layer design is critical. In this paper, we develop an image transmission model that allows the application layer (e.g., the user) to specify an image quality constraint, and optimizes the lower layer parameters of transmit power and packet length, to minimize the energy dissipation in image transmission over a given distance. The effectiveness of this approach is evaluated by applying the proposed energy optimization to a reference ZigBee system and a WiFi system, and also by comparing to an energy optimization study that does not consider any image quality constraint. Evaluations show that our scheme outperforms the default settings of the investigated commercial devices and saves a significant amount of energy at middle-to-large transmission distances. PMID:23508852
[Optimization of Energy Saving Measures with ABR-MBR Integrated Process].
Wu, Peng; Lu, Shuang-jun; Xu, Yue-zhong; Liu, Jie; Shen, Yao-liang
2015-08-01
High energy consumption and membrane fouling are important factors that limit the wide use of membrane bioreactor (MBR). In order to reduce energy consumption and delay the process of membrane fouling, the process of anaerobic baffled reactor (ABR)-MBR was used to treat domestic sewage. The structure of the process and conditions of nitrogen and phosphorus removal were optimized in this study. The results showed that energy consumption was reduced by 43% through optimizing the structure of ABR-MBR process. Meanwhile, the process achieved a high level of COD, NH: -N, TN and TP removal, with the average removal efficiencies of 91%, 85%, 76% and 86%, respectively. In addition, the added particulate media could effectively delay membrane fouling, while the formation process of membrane fouling was changed. The extracted amount of carbohydrates increased while the amount of proteins decreased. Finally, the potential was enhanced for the practical application of MBR. PMID:26592024
An Enhanced PSO-Based Clustering Energy Optimization Algorithm for Wireless Sensor Network.
Vimalarani, C; Subramanian, R; Sivanandam, S N
2016-01-01
Wireless Sensor Network (WSN) is a network which formed with a maximum number of sensor nodes which are positioned in an application environment to monitor the physical entities in a target area, for example, temperature monitoring environment, water level, monitoring pressure, and health care, and various military applications. Mostly sensor nodes are equipped with self-supported battery power through which they can perform adequate operations and communication among neighboring nodes. Maximizing the lifetime of the Wireless Sensor networks, energy conservation measures are essential for improving the performance of WSNs. This paper proposes an Enhanced PSO-Based Clustering Energy Optimization (EPSO-CEO) algorithm for Wireless Sensor Network in which clustering and clustering head selection are done by using Particle Swarm Optimization (PSO) algorithm with respect to minimizing the power consumption in WSN. The performance metrics are evaluated and results are compared with competitive clustering algorithm to validate the reduction in energy consumption. PMID:26881273
An Enhanced PSO-Based Clustering Energy Optimization Algorithm for Wireless Sensor Network
Vimalarani, C.; Subramanian, R.; Sivanandam, S. N.
2016-01-01
Wireless Sensor Network (WSN) is a network which formed with a maximum number of sensor nodes which are positioned in an application environment to monitor the physical entities in a target area, for example, temperature monitoring environment, water level, monitoring pressure, and health care, and various military applications. Mostly sensor nodes are equipped with self-supported battery power through which they can perform adequate operations and communication among neighboring nodes. Maximizing the lifetime of the Wireless Sensor networks, energy conservation measures are essential for improving the performance of WSNs. This paper proposes an Enhanced PSO-Based Clustering Energy Optimization (EPSO-CEO) algorithm for Wireless Sensor Network in which clustering and clustering head selection are done by using Particle Swarm Optimization (PSO) algorithm with respect to minimizing the power consumption in WSN. The performance metrics are evaluated and results are compared with competitive clustering algorithm to validate the reduction in energy consumption. PMID:26881273
An Energy Storage Assessment: Using Optimal Control Strategies to Capture Multiple Services
Wu, Di; Jin, Chunlian; Balducci, Patrick J.; Kintner-Meyer, Michael CW
2015-09-01
This paper presents a methodology for evaluating benefits of battery storage for multiple grid applications, including energy arbitrage, balancing service, capacity value, distribution system equipment deferral, and outage mitigation. In the proposed method, at each hour, a look-ahead optimization is first formulated and solved to determine battery base operating point. The minute by minute simulation is then performed to simulate the actual battery operation. This methodology is used to assess energy storage alternatives in Puget Sound Energy System. Different battery storage candidates are simulated for a period of one year to assess different value streams and overall benefits, as part of a financial feasibility evaluation of battery storage projects.
NASA Astrophysics Data System (ADS)
Cassidy, Ian L.; Scruggs, Jeffrey T.; Behrens, Sam
2011-08-01
In many applications of vibratory energy harvesting, the external disturbance is most appropriately modeled as a broadband stochastic process. Optimization of the average power generated from such disturbances is a feedback control problem, and solvable via LQG (linear-quadratic-Gaussian) control theory. Implementing the optimal feedback controller requires a power electronic drive capable of two-way power flow, which can impose dynamic relationships between the voltage and current of the transducer. Determining the optimal energy harvesting current control is accomplished by solving a nonstandard Riccati equation. In this paper we show that appropriate tuning of the passive parameters in the harvesting system results in a decoupled solution to the Riccati equation and a corresponding controller that only requires half of the states for feedback. However, even when such tuning methods are not used and the solution to the Riccati equation does not decouple, it is possible to determine the states in the feedback law that contribute the most to the average power generated by the harvester. As such, partial-state feedback gains can be optimized using a gradient descent method. Two energy harvesting examples are presented, including a single-degree-of-freedom oscillator with an electromagnetic actuator and a piezoelectric bimorph cantilever beam, to demonstrate these concepts.
Energy cost based design optimization method for medium temperature CPC collectors
NASA Astrophysics Data System (ADS)
Horta, Pedro; Osório, Tiago; Collares-Pereira, Manuel
2016-05-01
CPC collectors, approaching the ideal concentration limits established by non-imaging optics, can be designed to have such acceptance angles enabling fully stationary designs, useful for applications in the low temperature range (T < 100°C). Their use in the medium temperature range (100°C < T < 250°C) typically requires higher concentration factors in turn requiring seasonal tracking strategies. Considering the CPC design options in terms of effective concentration factor, truncation, concentrator height, mirror perimeter, seasonal tracking, trough spacing, etc., an energy cost function based design optimization method is presented in this article. Accounting for the impact of the design on its optical (optical efficiency, Incidence Angle Modifier, diffuse acceptance) and thermal performances (dependent on the concentration factor), the optimization function integrates design (e.g. mirror area, frame length, trough spacing/shading), concept (e.g. rotating/stationary components, materials) and operation (e.g. O&M, tilt shifts and tracking strategy) costs into a collector specific energy cost function, in €/(kWh.m2). The use of such function stands for a location and operating temperature dependent design optimization procedure, aiming at the lowest solar energy cost. Illustrating this approach, optimization results will be presented for a (tubular) evacuated absorber CPC design operating in Morocco.
NASA Astrophysics Data System (ADS)
Ganesh, V.; Dongare, Rameshwar K.; Balanarayan, P.; Gadre, Shridhar R.
2006-09-01
A linear-scaling scheme for estimating the electronic energy, gradients, and Hessian of a large molecule at ab initio level of theory based on fragment set cardinality is presented. With this proposition, a general, cardinality-guided molecular tailoring approach (CG-MTA) for ab initio geometry optimization of large molecules is implemented. The method employs energy gradients extracted from fragment wave functions, enabling computations otherwise impractical on PC hardware. Further, the method is readily amenable to large scale coarse-grain parallelization with minimal communication among nodes, resulting in a near-linear speedup. CG-MTA is applied for density-functional-theory-based geometry optimization of a variety of molecules including α-tocopherol, taxol, γ-cyclodextrin, and two conformations of polyglycine. In the tests performed, energy and gradient estimates obtained from CG-MTA during optimization runs show an excellent agreement with those obtained from actual computation. Accuracy of the Hessian obtained employing CG-MTA provides good hope for the application of Hessian-based geometry optimization to large molecules.
NASA Astrophysics Data System (ADS)
Meyers, Johan; Munters, Wim; Goit, Jay
2015-11-01
We investigate optimal control of wind-farm boundary layers, considering the individual wind turbines as flow actuators. By controlling the thrust coefficients of the turbines as function of time, the energy extraction can be dynamically regulated with the aim to optimally influence the flow field and the vertical energy transport. To this end, we use Large-Eddy Simulations (LES) of wind-farm boundary layers in a receding-horizon optimal control framework. Recently, the approach was applied to fully developed wind-farm boundary layers in a 7D by 6D aligned wind-turbine arrangement. For this case, energy extraction increased up to 16%, related to improved wake mixing by slightly anti-correlating the turbine thrust coefficient with the local wind speed at the turbine level. Here we discuss optimal control results for finite wind farms that are characterized by entrance effects and a developing internal boundary layer above the wind farm. Both aligned and staggered arrangement patterns are considered, and a range of different constraints on the controls is included. The authors acknowledge support from the European Research Council (FP7-Ideas, grant no. 306471). Simulations were performed on the infrastructure of the Flemish Supercomputer Center, funded by the Hercules Foundation and the Flemish Governement.
Stabilization of microgrid with intermittent renewable energy sources by SMES with optimal coil size
NASA Astrophysics Data System (ADS)
Saejia, M.; Ngamroo, I.
2011-11-01
It is well known that the superconducting coil is the vital part of a superconducting magnetic energy storage (SMES) unit. This paper deals with the power controller design of a SMES unit with an optimal coil size for stabilization of an isolated microgrid. The study microgrid consists of renewable energy sources with intermittent power outputs i.e., wind and photovoltaic. Since power generations from such renewable sources are unpredictable and variable, these result in power fluctuations in a microgrid. To stabilize power fluctuations, a SMES unit with a fast control of active and reactive power can be applied. The structure of a power controller is the practical proportional-integral (PI). Based on the minimization of the variance of power fluctuations from renewable sources as well as the initial stored energy of SMES, the optimal PI parameters and coil size are automatically and simultaneously tuned by a particle swarm optimization. Simulation studies show that the proposed SMES controller with an optimal coil size is able to effectively alleviate power fluctuations under various power patterns from intermittent renewable sources.
Kafetzoglou, Stella; Aristomenopoulos, Giorgos; Papavassiliou, Symeon
2015-01-01
Among the key aspects of the Internet of Things (IoT) is the integration of heterogeneous sensors in a distributed system that performs actions on the physical world based on environmental information gathered by sensors and application-related constraints and requirements. Numerous applications of Wireless Sensor Networks (WSNs) have appeared in various fields, from environmental monitoring, to tactical fields, and healthcare at home, promising to change our quality of life and facilitating the vision of sensor network enabled smart cities. Given the enormous requirements that emerge in such a setting-both in terms of data and energy-data aggregation appears as a key element in reducing the amount of traffic in wireless sensor networks and achieving energy conservation. Probabilistic frameworks have been introduced as operational efficient and performance effective solutions for data aggregation in distributed sensor networks. In this work, we introduce an overall optimization approach that improves and complements such frameworks towards identifying the optimal probability for a node to aggregate packets as well as the optimal aggregation period that a node should wait for performing aggregation, so as to minimize the overall energy consumption, while satisfying certain imposed delay constraints. Primal dual decomposition is employed to solve the corresponding optimization problem while simulation results demonstrate the operational efficiency of the proposed approach under different traffic and topology scenarios. PMID:26270664
On-line economic optimization of energy systems using weather forecast information.
Zavala, V. M.; Constantinescu, E. M.; Krause, T.; Anitescu, M.
2009-01-01
We establish an on-line optimization framework to exploit weather forecast information in the operation of energy systems. We argue that anticipating the weather conditions can lead to more proactive and cost-effective operations. The framework is based on the solution of a stochastic dynamic real-time optimization (D-RTO) problem incorporating forecasts generated from a state-of-the-art weather prediction model. The necessary uncertainty information is extracted from the weather model using an ensemble approach. The accuracy of the forecast trends and uncertainty bounds are validated using real meteorological data. We present a numerical simulation study in a building system to demonstrate the developments.
Planning horizon for a predictive optimal controller for thermal energy storage systems
Krarti, M.; Henze, G.P.; Bell, D.
1999-07-01
This paper presents the results of a detailed simulation analysis to determine the planning horizon for a predictive optimal controller for thermal energy storage (TES) systems. The objective of the simulation analysis is to determine the sensitivity of the performance of a TES optimal controller and the planning horizon length to different design parameters, including: chiller capacity, cooling plant model, storage system capacity, and load profile. The analysis is performed using two commercial buildings: a 20-floor office building in Wisconsin, and a hotel in California.
Optimization problems for WSNs: trade-off between synchronization errors and energy consumption
NASA Astrophysics Data System (ADS)
Manita, Larisa
2016-02-01
We discuss a class of optimization problems related to stochastic models of wireless sensor networks (WSNs). We consider a sensor network that consists of a single server node and m groups of identical client nodes. The goal is to minimize the cost functional which accumulates synchronization errors and energy consumption over a given time interval. The control function u(t) = (u1(t),...,um(t)) corresponds to the power of the server node transmitting synchronization signals to the groups of clients. We find the structure of extremal trajectories. We show that optimal solutions for such models can contain singular arcs.
Expanded explorations into the optimization of an energy function for protein design
Huang, Yao-ming; Bystroff, Christopher
2014-01-01
Nature possesses a secret formula for the energy as a function of the structure of a protein. In protein design, approximations are made to both the structural representation of the molecule and to the form of the energy equation, such that the existence of a general energy function for proteins is by no means guaranteed. Here we present new insights towards the application of machine learning to the problem of finding a general energy function for protein design. Machine learning requires the definition of an objective function, which carries with it the implied definition of success in protein design. We explored four functions, consisting of two functional forms, each with two criteria for success. Optimization was carried out by a Monte Carlo search through the space of all variable parameters. Cross-validation of the optimized energy function against a test set gave significantly different results depending on the choice of objective function, pointing to relative correctness of the built-in assumptions. Novel energy cross-terms correct for the observed non-additivity of energy terms and an imbalance in the distribution of predicted amino acids. This paper expands on the work presented at ACM-BCB, Orlando FL , October 2012. PMID:24384706
Expanded explorations into the optimization of an energy function for protein design.
Huang, Yao-Ming; Bystroff, Christopher
2013-01-01
Nature possesses a secret formula for the energy as a function of the structure of a protein. In protein design, approximations are made to both the structural representation of the molecule and to the form of the energy equation, such that the existence of a general energy function for proteins is by no means guaranteed. Here, we present new insights toward the application of machine learning to the problem of finding a general energy function for protein design. Machine learning requires the definition of an objective function, which carries with it the implied definition of success in protein design. We explored four functions, consisting of two functional forms, each with two criteria for success. Optimization was carried out by a Monte Carlo search through the space of all variable parameters. Cross-validation of the optimized energy function against a test set gave significantly different results depending on the choice of objective function, pointing to relative correctness of the built-in assumptions. Novel energy cross terms correct for the observed nonadditivity of energy terms and an imbalance in the distribution of predicted amino acids. This paper expands on the work presented at the 2012 ACM-BCB. PMID:24384706
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
Ralf Janowsky, Ph.D.; Tracey Mole, Ph.D.
2007-12-31
The Evonik Degussa Corporation is the global market leader in the specialty chemicals industry. Innovative products and system solutions make an indispensable contribution to our customers' success. We refer to this as "creating essentials". In fiscal 2004, Degussa's 45,000 employees worldwide generated sales of 11.2 billion euros and operating profits (EBIT) of 965 million euros. Evonik Degussa Corporation has performed a plant wide energy usage assessment at the Mapleton, Illinois facility, which consumed 1,182,330 MMBTU in 2003. The purpose of this study was to identify opportunities for improvement regarding the plant’s utility requirements specific to their operation. The production is based mainly on natural gas usage for steam, process heating and hydrogen production. The current high price for natural gas in the US is not very competitive compared to other countries. Therefore, all efforts must be taken to minimize the utility consumption in order to maximize market position and minimize fixed cost increases due to the rising costs of energy. The main objective of this plant wide assessment was to use a methodology called Site Energy Modelling (SitE Modelling) to identify areas of potential improvement for energy savings, either in implementing a single process change or in changing the way different processes interact with each other. The overall goal was to achieve energy savings of more than 10% compared to the 2003 energy figures of the Mapleton site. The final savings breakdown is provided below: - 4.1% savings for steam generation and delivery These savings were accomplished through better control schemes, more constant and optimized loading of the boilers and increased boiler efficiency through an advanced control schemes. - 1.6% savings for plant chemical processing These saving were accomplished through optimized processing heating efficiency and batch recipes, as well as an optimized production schedule to help equalize the boiler load (e
NASA Astrophysics Data System (ADS)
Hang, Yin
Buildings in the United States are responsible for 41% of the primary energy use and 30% of carbon dioxide emissions. Due to mounting concerns about climate change and resource depletion, meeting building heating and cooling demand with renewable energy has attracted increasing attention in the energy system design of green buildings. One of these approaches, the solar absorption cooling and heating (SACH) technology can be a key solution to addressing the energy and environmental challenges. SACH system is an integration of solar thermal heating system and solar thermal driven absorption cooling system. So far, SACH systems still remain at the demonstration and testing stage due to not only its high cost but also complicated system characteristics. This research aims to develop a methodology to evaluate the life cycle energy, economic and environmental performance of SACH systems by high-fidelity simulations validated by experimental data. The developed methodology can be used to assist the system design. In order to achieve this goal, the study includes four objectives as follows: * Objective 1: Develop the evaluation model for the SACH system. The model includes three aspects: energy, economy, and environment from a life cycle point of view. * Objective 2: Validate the energy system model by solar experiments performance data. * Objective 3: Develop a fast and effective multi-objective optimization methodology to find the optimal system configuration which achieves the maximum system benefits on energy, economy and environment. Statistic techniques are explored to reveal the relations between the system key parameters and the three evaluation targets. The Pareto front is generated by solving this multi-objective optimization problem. * Objective 4: Apply the developed assessment methodology to different building types and locations. Furthermore, this study considered the influence of the input uncertainties on the overall system performance. The sensitivity
NASA Astrophysics Data System (ADS)
Hynds, Taylor D.; Kauffman, Jeffrey L.
2015-04-01
Piezoelectric-based vibration energy harvesting is of interest in a wide range of applications, and a number of harvesting schemes have been proposed and studied { primarily when operating under steady state conditions. However, energy harvesting behavior is rarely studied in systems with transient excitations. This paper will work to develop an understanding of this behavior within the context of a particular vibration reduction technique, resonance frequency detuning. Resonance frequency detuning provides a method of reducing mechanical response at structural resonances as the excitation frequency sweeps through a given range. This technique relies on switching the stiffness state of a structure at optimal times to detune its resonance frequency from that of the excitation. This paper examines how this optimal switch may be triggered in terms of the energy harvested, developing a normalized optimal switch energy that is independent of the open- and short-circuit resistances. Here the open- and short-circuit shunt resistances refer to imposed conditions that approximate the open- and short-circuit conditions, via high and low resistance shunts. These conditions are practically necessary to harvest the small amounts of power needed to switch stiffness states, as open-circuit and closed-circuit refer to infinite resistance and zero resistance, respectively, and therefore no energy passes through the harvesting circuit. The limiting stiffness states are then defined by these open- and short-circuit resistances. The optimal switch energy is studied over a range of sweep rates, damping ratios, and coupling coefficients; it is found to increase with the coupling coefficient and decrease as the sweep rate and damping ratio increase, behavior which is intuitive. Higher coupling means more energy is converted by the piezoelectric material, and therefore more energy is harvested in a given time; an increased sweep rate means resonance is reached sooner, and there will less
NASA Astrophysics Data System (ADS)
van Kessel, Rick; Wattez, Ambroise; Bauer, Pavol
2014-03-01
This work presents an integral approach to the power electronic challenges that are faced in DEAP-based energy conversion, such as wide converter operating ranges and high peak-to-average ratios. It is shown that for small strain cycles, the losses in the Power Electronic Converter (PEC) due to the cyclic charging and discharging are dominant. The efficiency profile of a realistic, high-voltage modular PEC was measured and fed into an optimization algorithm. The current amplitude, phase and shape are optimized, and different cycle types are compared. With optimization results for a wide strain range, it is demonstrated that with properly adapted harvesting cycles, the overall conversion efficiency is significantly improved, especially for small strain cycles.
NASA Astrophysics Data System (ADS)
Arya, L. D.; Kela, K. B.
2013-12-01
This paper describes a methodology for determination of optimum failure rate and repair time for each component of a meshed distribution system. In this paper the reliability indices for a sample meshed network are optimized. An objective function incorporating customer and energy based reliability indices and their target values is formulated. These indices are function of failure rate and repair time of a section of a distribution network. Modification of failure rate and repair time modifies the cost attached to them. Hence the optimization of the objective function is achieved by modifying the failure rate and repair time of each section of the meshed distribution system accounting constraint on budget allocated. The problem has been solved using population based differential evolution and bare bones particle swarm optimization techniques and results have been compared for a sample meshed distribution system.
An energy-optimized collimator design for a CZT-based SPECT camera
NASA Astrophysics Data System (ADS)
Weng, Fenghua; Bagchi, Srijeeta; Zan, Yunlong; Huang, Qiu; Seo, Youngho
2016-01-01
In single photon emission computed tomography, it is a challenging task to maintain reasonable performance using only one specific collimator for radiotracers over a broad spectrum of diagnostic photon energies, since photon scatter and penetration in a collimator differ with the photon energy. Frequent collimator exchanges are inevitable in daily clinical SPECT imaging, which hinders throughput while subjecting the camera to operational errors and damage. Our objective is to design a collimator, which is independent of the photon energy, performs reasonably well for commonly used radiotracers with low- to medium-energy levels of gamma emissions. Using the Geant4 simulation toolkit, we simulated and evaluated a parallel-hole collimator mounted to a CZT detector. With the pixel-geometry-matching collimation, the pitch of the collimator hole was fixed to match the pixel size of the CZT detector throughout this work. Four variables, hole shape, hole length, hole radius/width and the source-to-collimator distance were carefully studied. Scatter and penetration of the collimator, sensitivity and spatial resolution of the system were assessed for four radionuclides including 57Co, 99mTc, 123I and 111In, with respect to the aforementioned four variables. An optimal collimator was then decided upon such that it maximized the total relative sensitivity (TRS) for the four considered radionuclides while other performance parameters, such as scatter, penetration and spatial resolution, were benchmarked to prevalent commercial scanners and collimators. Digital phantom studies were also performed to validate the system with the optimal square-hole collimator (23 mm hole length, 1.28 mm hole width, and 0.32 mm septal thickness) in terms of contrast, contrast-to-noise ratio and recovery ratio. This study demonstrates promise of our proposed energy-optimized collimator to be used in a CZT-based gamma camera, with comparable or even better imaging performance versus commercial
An energy-optimized collimator design for a CZT-based SPECT camera
Weng, Fenghua; Bagchi, Srijeeta; Zan, Yunlong; Huang, Qiu; Seo, Youngho
2015-01-01
In single photon emission computed tomography, it is a challenging task to maintain reasonable performance using only one specific collimator for radio-tracers over a broad spectrum of diagnostic photon energies, since photon scatter and penetration in a collimator differ with the photon energy. Frequent collimator exchanges are inevitable in daily clinical SPECT imaging, which hinders throughput while subjecting the camera to operational errors and damage. Our objective is to design a collimator, which independent of the photon energy performs reasonably well for commonly used radiotracers with low- to medium-energy levels of gamma emissions. Using the Geant4 simulation toolkit, we simulated and evaluated a parallel-hole collimator mounted to a CZT detector. With the pixel-geometry-matching collimation, the pitch of the collimator hole was fixed to match the pixel size of the CZT detector throughout this work. Four variables, hole shape, hole length, hole radius/width and the source-to-collimator distance were carefully studied. Scatter and penetration of the collimator, sensitivity and spatial resolution of the system were assessed for four radionuclides including 57Co, 99mTc, 123I and 111In, with respect to the aforementioned four variables. An optimal collimator was then decided upon such that it maximized the total relative sensitivity (TRS) for the four considered radionuclides while other performance parameters, such as scatter, penetration and spatial resolution, were benchmarked to prevalent commercial scanners and collimators. Digital phantom studies were also performed to validate the system with the optimal square-hole collimator (23 mm hole length, 1.28 mm hole width, 0.32 mm septal thickness) in terms of contrast, contrast-to-noise ratio and recovery ratio. This study demonstrates promise of our proposed energy-optimized collimator to be used in a CZT-based gamma camera, with comparable or even better imaging performance versus commercial collimators
Real-time Ocean Wave Prediction for Optimal Performance of a Wave Energy Converter
NASA Astrophysics Data System (ADS)
Cavaglieri, Daniele; Bewley, Thomas
2013-11-01
In recent years, there has been a growing interest in renewable energy. Among all the available possibilities, wave energy conversion, due to the huge availability of energy that the ocean could provide, represents nowadays one of the most promising solutions. However, the efficiency of a wave energy converter for ocean wave energy harvesting is still far from making it competitive with more mature fields of renewable energy, such as solar and wind energy. One of the main problems is related to the inability to accurately predict the profile of oncoming waves approaching the wave energy converter. For this reason, we developed a new hybrid method for state estimation of nonlinear systems, which is based on a variational formulation of an ensemble smoother, combined with the formulation of the ensemble Kalman smoother. This method has been employed for the optimal forecasting of ocean waves via sensors placed on an array of wave energy converters. The coupled simulation of ocean waves and energy devices has been carried out leveraging a nonlinear High Order Spectral code.
Improvement of the GERDA Ge Detectors Energy Resolution by an Optimized Digital Signal Processing
NASA Astrophysics Data System (ADS)
Benato, G.; D'Andrea, V.; Cattadori, C.; Riboldi, S.
GERDA is a new generation experiment searching for neutrinoless double beta decay of 76Ge, operating at INFN Gran Sasso Laboratories (LNGS) since 2010. Coaxial and Broad Energy Germanium (BEGe) Detectors have been operated in liquid argon (LAr) in GERDA Phase I. In the framework of the second GERDA experimental phase, both the contacting technique, the connection to and the location of the front end readout devices are novel compared to those previously adopted, and several tests have been performed. In this work, starting from considerations on the energy scale stability of the GERDA Phase I calibrations and physics data sets, an optimized pulse filtering method has been developed and applied to the Phase II pilot tests data sets, and to few GERDA Phase I data sets. In this contribution the detector performances in term of energy resolution and time stability are here presented. The improvement of the energy resolution, compared to standard Gaussian shaping adopted for Phase I data analysis, is discussed and related to the optimized noise filtering capability. The result is an energy resolution better than 0.1% at 2.6 MeV for the BEGe detectors operated in the Phase II pilot tests and an improvement of the energy resolution in LAr of about 8% achieved on the GERDA Phase I calibration runs, compared to previous analysis algorithms.
26 CFR 1.871-7 - Taxation of nonresident alien individuals not engaged in U.S. business.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Taxation of nonresident alien individuals not engaged in U.S. business. 1.871-7 Section 1.871-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Nonresident Aliens and Foreign Corporations § 1.871-7 Taxation of nonresident...
"We Need a Woman, We Need a Black Woman": Gender, Race, and Identity Taxation in the Academy
ERIC Educational Resources Information Center
Hirshfield, Laura E.; Joseph, Tiffany D.
2012-01-01
In 1994, Amado Padilla used the phrase "cultural taxation" to describe the extra burden of service responsibilities placed upon minority faculty members because of their racial or ethnic background. In this paper, we expand upon Padilla's work and introduce the concept of "identity taxation" to encompass how other marginalised social identities…
26 CFR 1.338-4 - Aggregate deemed sale price; various aspects of taxation of the deemed asset sale.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 4 2014-04-01 2014-04-01 false Aggregate deemed sale price; various aspects of taxation of the deemed asset sale. 1.338-4 Section 1.338-4 Internal Revenue INTERNAL REVENUE SERVICE... § 1.338-4 Aggregate deemed sale price; various aspects of taxation of the deemed asset sale. (a)...
26 CFR 1.338-4 - Aggregate deemed sale price; various aspects of taxation of the deemed asset sale.
Code of Federal Regulations, 2012 CFR
2012-04-01
... taxation of the deemed asset sale. 1.338-4 Section 1.338-4 Internal Revenue INTERNAL REVENUE SERVICE... § 1.338-4 Aggregate deemed sale price; various aspects of taxation of the deemed asset sale. (a) Scope. This section provides rules under section 338(a)(1) to determine the aggregate deemed sale price...
26 CFR 1.338-4 - Aggregate deemed sale price; various aspects of taxation of the deemed asset sale.
Code of Federal Regulations, 2013 CFR
2013-04-01
... taxation of the deemed asset sale. 1.338-4 Section 1.338-4 Internal Revenue INTERNAL REVENUE SERVICE... § 1.338-4 Aggregate deemed sale price; various aspects of taxation of the deemed asset sale. (a) Scope. This section provides rules under section 338(a)(1) to determine the aggregate deemed sale price...
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 9 2012-04-01 2012-04-01 false Taxation of foreign investment in United States real property interests, definition of terms. 1.897-1 Section 1.897-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Miscellaneous Provisions § 1.897-1 Taxation...
Some Marginalist Intuition Concerning the Optimal Commodity Tax Problem
ERIC Educational Resources Information Center
Brett, Craig
2006-01-01
The author offers a simple intuition that can be exploited to derive and to help interpret some canonical results in the theory of optimal commodity taxation. He develops and explores the principle that the marginal social welfare loss per last unit of tax revenue generated be equalized across tax instruments. A simple two-consumer,…
Kafetzoglou, Stella; Aristomenopoulos, Giorgos; Papavassiliou, Symeon
2015-01-01
Among the key aspects of the Internet of Things (IoT) is the integration of heterogeneous sensors in a distributed system that performs actions on the physical world based on environmental information gathered by sensors and application-related constraints and requirements. Numerous applications of Wireless Sensor Networks (WSNs) have appeared in various fields, from environmental monitoring, to tactical fields, and healthcare at home, promising to change our quality of life and facilitating the vision of sensor network enabled smart cities. Given the enormous requirements that emerge in such a setting—both in terms of data and energy—data aggregation appears as a key element in reducing the amount of traffic in wireless sensor networks and achieving energy conservation. Probabilistic frameworks have been introduced as operational efficient and performance effective solutions for data aggregation in distributed sensor networks. In this work, we introduce an overall optimization approach that improves and complements such frameworks towards identifying the optimal probability for a node to aggregate packets as well as the optimal aggregation period that a node should wait for performing aggregation, so as to minimize the overall energy consumption, while satisfying certain imposed delay constraints. Primal dual decomposition is employed to solve the corresponding optimization problem while simulation results demonstrate the operational efficiency of the proposed approach under different traffic and topology scenarios. PMID:26270664
Optimization of heat transfer in a high-energy booster rocket
Tarpley, C.; Lewis, M.J.
1994-11-01
This article describes the performance optimization of a high-energy booster rocket powered by the proton/antiproton annihilation reaction. This procedure can be used to evaluate and optimize new concepts for advanced high-energy propulsion systems as well as to improve performance in nuclear thermal engines if coupled with a neutronics code. The analysis includes a one-speed estimation of the gamma radiation transport in the engine shield and an analysis of the heat transfer to the hydrogen working fluid as it flows through the engine. The engine performance model is optimized using the method of feasible directions concept as implemented in the CONMIN Fortran package. CONMIN is used to explore the performance limit of this conceptual design and develop sensitivity information from which conclusions are drawn about the direction of future work. The optimized engine has a specific impulse of 1037 s. The total launch system mass as designed is 890,000 kg, which includes a payload of 50,000 kg. 16 refs.
Giantsoudi, Drosoula; Grassberger, Clemens; Craft, David; Niemierko, Andrzej; Trofimov, Alexei; Paganetti, Harald
2013-09-01
Purpose: To investigate the feasibility and potential clinical benefit of linear energy transfer (LET) guided plan optimization in intensity modulated proton therapy (IMPT). Methods and Materials: A multicriteria optimization (MCO) module was used to generate a series of Pareto-optimal IMPT base plans (BPs), corresponding to defined objectives, for 5 patients with head-and-neck cancer and 2 with pancreatic cancer. A Monte Carlo platform was used to calculate dose and LET distributions for each BP. A custom-designed MCO navigation module allowed the user to interpolate between BPs to produce deliverable Pareto-optimal solutions. Differences among the BPs were evaluated for each patient, based on dose–volume and LET–volume histograms and 3-dimensional distributions. An LET-based relative biological effectiveness (RBE) model was used to evaluate the potential clinical benefit when navigating the space of Pareto-optimal BPs. Results: The mean LET values for the target varied up to 30% among the BPs for the head-and-neck patients and up to 14% for the pancreatic cancer patients. Variations were more prominent in organs at risk (OARs), where mean LET values differed by a factor of up to 2 among the BPs for the same patient. An inverse relation between dose and LET distributions for the OARs was typically observed. Accounting for LET-dependent variable RBE values, a potential improvement on RBE-weighted dose of up to 40%, averaged over several structures under study, was noticed during MCO navigation. Conclusions: We present a novel strategy for optimizing proton therapy to maximize dose-averaged LET in tumor targets while simultaneously minimizing dose-averaged LET in normal tissue structures. MCO BPs show substantial LET variations, leading to potentially significant differences in RBE-weighted doses. Pareto-surface navigation, using both dose and LET distributions for guidance, provides the means for evaluating a large variety of deliverable plans and aids in
Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M. A.
2014-01-01
This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods. PMID:24883374
Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M A
2014-01-01
This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods. PMID:24883374
Optimal Deployment of Thermal Energy Storage under Diverse Economic and Climate Conditions
DeForest, Nicolas; Mendes, Goncalo; Stadler, Michael; Feng, Wei; Lai, Judy; Marnay, Chris
2014-04-15
This paper presents an investigation of the economic benefit of thermal energy storage (TES) for cooling, across a range of economic and climate conditions. Chilled water TES systems are simulated for a large office building in four distinct locations, Miami in the U.S.; Lisbon, Portugal; Shanghai, China; and Mumbai, India. Optimal system size and operating schedules are determined using the optimization model DER-CAM, such that total cost, including electricity and amortized capital costs are minimized. The economic impacts of each optimized TES system is then compared to systems sized using a simple heuristic method, which bases system size as fraction (50percent and 100percent) of total on-peak summer cooling loads. Results indicate that TES systems of all sizes can be effective in reducing annual electricity costs (5percent-15percent) and peak electricity consumption (13percent-33percent). The investigation also indentifies a number of criteria which drive TES investment, including low capital costs, electricity tariffs with high power demand charges and prolonged cooling seasons. In locations where these drivers clearly exist, the heuristically sized systems capture much of the value of optimally sized systems; between 60percent and 100percent in terms of net present value. However, in instances where these drivers are less pronounced, the heuristic tends to oversize systems, and optimization becomes crucial to ensure economically beneficial deployment of TES, increasing the net present value of heuristically sized systems by as much as 10 times in some instances.
Optimization of piezoelectric bistable composite plates for broadband vibrational energy harvesting
NASA Astrophysics Data System (ADS)
Betts, David N.; Kim, H. Alicia; Bowen, Christopher R.; Inman, Daniel J.
2012-04-01
This paper presents a unique arrangement of bistable composite plates with piezoelectric patches bonded to its surface to perform broadband vibration-based energy harvesting from ambient mechanical vibrations. These bistable nonlinear devices have been shown to have improved power generation compared to conventional resonant systems and can be designed to occupy smaller volumes than bistable magnetic cantilever systems. This paper presents the results of an optimization study of bistable composites that are capable of generating greater electrical power from a smaller space by discovering the correct geometric configuration for energy harvesting. Optimum solutions are investigated in a series of design parameter studies intended to reveal the complex interactions of the physical constraints and design requirements. The proposed approach considers the optimal choice of device aspect ratio, thickness, laminate stacking sequence, and piezoelectric surface area. Increased electrical output is found for geometries and piezoelectric configurations which have not been considered previously.
Effective Energy Simulation and Optimal Design of Side-lit Buildings with Venetian Blinds
NASA Astrophysics Data System (ADS)
Cheng, Tian
Venetian blinds are popularly used in buildings to control the amount of incoming daylight for improving visual comfort and reducing heat gains in air-conditioning systems. Studies have shown that the proper design and operation of window systems could result in significant energy savings in both lighting and cooling. However, there is no convenient computer tool that allows effective and efficient optimization of the envelope of side-lit buildings with blinds now. Three computer tools, Adeline, DOE2 and EnergyPlus widely used for the above-mentioned purpose have been experimentally examined in this study. Results indicate that the two former tools give unacceptable accuracy due to unrealistic assumptions adopted while the last one may generate large errors in certain conditions. Moreover, current computer tools have to conduct hourly energy simulations, which are not necessary for life-cycle energy analysis and optimal design, to provide annual cooling loads. This is not computationally efficient, particularly not suitable for optimal designing a building at initial stage because the impacts of many design variations and optional features have to be evaluated. A methodology is therefore developed for efficient and effective thermal and daylighting simulations and optimal design of buildings with blinds. Based on geometric optics and radiosity method, a mathematical model is developed to reasonably simulate the daylighting behaviors of venetian blinds. Indoor illuminance at any reference point can be directly and efficiently computed. They have been validated with both experiments and simulations with Radiance. Validation results show that indoor illuminances computed by the new models agree well with the measured data, and the accuracy provided by them is equivalent to that of Radiance. The computational efficiency of the new models is much higher than that of Radiance as well as EnergyPlus. Two new methods are developed for the thermal simulation of buildings. A
Lee, JongHyup; Pak, Dohyun
2016-01-01
For practical deployment of wireless sensor networks (WSN), WSNs construct clusters, where a sensor node communicates with other nodes in its cluster, and a cluster head support connectivity between the sensor nodes and a sink node. In hybrid WSNs, cluster heads have cellular network interfaces for global connectivity. However, when WSNs are active and the load of cellular networks is high, the optimal assignment of cluster heads to base stations becomes critical. Therefore, in this paper, we propose a game theoretic model to find the optimal assignment of base stations for hybrid WSNs. Since the communication and energy cost is different according to cellular systems, we devise two game models for TDMA/FDMA and CDMA systems employing power prices to adapt to the varying efficiency of recent wireless technologies. The proposed model is defined on the assumptions of the ideal sensing field, but our evaluation shows that the proposed model is more adaptive and energy efficient than local selections. PMID:27589743
Energy aware swarm optimization with intercluster search for wireless sensor network.
Thilagavathi, Shanmugasundaram; Geetha, Bhavani Gnanasambandan
2015-01-01
Wireless sensor networks (WSNs) are emerging as a low cost popular solution for many real-world challenges. The low cost ensures deployment of large sensor arrays to perform military and civilian tasks. Generally, WSNs are power constrained due to their unique deployment method which makes replacement of battery source difficult. Challenges in WSN include a well-organized communication platform for the network with negligible power utilization. In this work, an improved binary particle swarm optimization (PSO) algorithm with modified connected dominating set (CDS) based on residual energy is proposed for discovery of optimal number of clusters and cluster head (CH). Simulations show that the proposed BPSO-T and BPSO-EADS perform better than LEACH- and PSO-based system in terms of energy savings and QOS. PMID:25918741
Energy Aware Swarm Optimization with Intercluster Search for Wireless Sensor Network
Thilagavathi, Shanmugasundaram; Gnanasambandan Geetha, Bhavani
2015-01-01
Wireless sensor networks (WSNs) are emerging as a low cost popular solution for many real-world challenges. The low cost ensures deployment of large sensor arrays to perform military and civilian tasks. Generally, WSNs are power constrained due to their unique deployment method which makes replacement of battery source difficult. Challenges in WSN include a well-organized communication platform for the network with negligible power utilization. In this work, an improved binary particle swarm optimization (PSO) algorithm with modified connected dominating set (CDS) based on residual energy is proposed for discovery of optimal number of clusters and cluster head (CH). Simulations show that the proposed BPSO-T and BPSO-EADS perform better than LEACH- and PSO-based system in terms of energy savings and QOS. PMID:25918741
García-Quismondo, Enrique; Santos, Cleis; Lado, Julio; Palma, Jesús; Anderson, Marc A
2013-10-15
Capacitive deionization (CDI) is a rapidly emerging desalination technology that promises to deliver clean water while storing energy in the electrical double layer (EDL) near a charged surface in a capacitive format. Whereas most research in this subject area has been devoted to using CDI for removing salts, little attention has been paid to the energy storage aspect of the technology. However, it is energy storage that would allow this technology to compete with other desalination processes if this energy could be stored and reused efficiently. This requires that the operational aspects of CDI be optimized with respect to energy used both during the removal of ions as well as during the regeneration cycle. This translates into the fact that currents applied during deionization (charging the EDL) will be different from those used in regeneration (discharge). This paper provides a mechanistic analysis of CDI in terms of energy consumption and energy efficiencies during the charging and discharging of the system under several scenarios. In a previous study, we proposed an operational buffer mode in which an effective separation of deionization and regeneration steps would allow one to better define the energy balance of this CDI process. This paper reports on using this concept, for optimizing energy efficiency, as well as to improve upon the electro-adsorption of ions and system lifetime. Results obtained indicate that real-world operational modes of running CDI systems promote the development of new and unexpected behavior not previously found, mainly associated with the inhomogeneous distribution of ions across the structure of the electrodes. PMID:24015835
Development of a Platform for Simulating and Optimizing Thermoelectric Energy Systems
NASA Astrophysics Data System (ADS)
Kreuder, John J.
Thermoelectrics are solid state devices that can convert thermal energy directly into electrical energy. They have historically been used only in niche applications because of their relatively low efficiencies. With the advent of nanotechnology and improved manufacturing processes thermoelectric materials have become less costly and more efficient As next generation thermoelectric materials become available there is a need for industries to quickly and cost effectively seek out feasible applications for thermoelectric heat recovery platforms. Determining the technical and economic feasibility of such systems requires a model that predicts performance at the system level. Current models focus on specific system applications or neglect the rest of the system altogether, focusing on only module design and not an entire energy system. To assist in screening and optimizing entire energy systems using thermoelectrics, a novel software tool, Thermoelectric Power System Simulator (TEPSS), is developed for system level simulation and optimization of heat recovery systems. The platform is designed for use with a generic energy system so that most types of thermoelectric heat recovery applications can be modeled. TEPSS is based on object-oriented programming in MATLABRTM. A modular, shell based architecture is developed to carry out concept generation, system simulation and optimization. Systems are defined according to the components and interconnectivity specified by the user. An iterative solution process based on Newton's Method is employed to determine the system's steady state so that an objective function representing the cost of the system can be evaluated at the operating point. An optimization algorithm from MATLAB's Optimization Toolbox uses sequential quadratic programming to minimize this objective function with respect to a set of user specified design variables and constraints. During this iterative process many independent system simulations are executed and
NASA Astrophysics Data System (ADS)
Baumgarten, Andreas
2013-04-01
Soil taxation and soil classification are important drivers of soil science in Austria. However, the tasks are quite different: whereas soil taxation aims at the evaluation of the productivity potential of the soil, soil classification focusses on the natural development and - especially nowadays - on functionality of the soil. Since the foundation of the Austrian Soil Science Society (ASSS), representatives both directions of the description of the soil have been involved in the common actions of the society. In the first years it was a main target to improve and standardize field descriptions of the soil. Although both systems differ in the general layout, the experts should comply with identical approaches. According to this work, a lot of effort has been put into the standardization of the soil classification system, thus ensuring a common basis. The development, state of the art and further development of both classification and taxation systems initiated and carried out by the ASSS will be shown.
Integration of Low Energy Technologies for Optimal Building and Space Conditioning Design
D.E. Fisher
2006-01-07
EnergyPlus is the DOE's newest building energy simulation engine. It was developed specifically to support the design of low energy building systems. This project focused on developing new low energy building simulation models for EnergyPlus, verifying and validating new and existing EnergyPlus models and transferring the new technology to the private sector. The project focused primarily on geothermal and radiant technologies, which are related by the fact that both are based on hydronic system design. As a result of this project eight peer reviewed journal and conference papers were added to the archival literature and five technical reports were published as M.S. theses and are available in the archival literature. In addition, several reports, including a trombe wall validation report were written for web publication. Thirteen new or significantly enhanced modules were added to the EnergyPlus source code and forty-two new or significantly enhanced sections were added to the EnergyPlus documentation as a result of this work. A low energy design guide was also developed as a pedagogical tool and is available for web publication. Finally several tools including a hybrid ground source heat pump optimization program and a geothermal heat pump parameter estimation tool were developed for research and design and are available for web publication.
Krstulovich, S.F.
1986-11-12
This report is developed as part of the Fermilab Central Computing Facility Project Title II Design Documentation Update under the provisions of DOE Document 6430.1, Chapter XIII-21, Section 14, paragraph a. As such, it concentrates primarily on HVAC mechanical systems design optimization and cost analysis and should be considered as a supplement to the Title I Design Report date March 1986 wherein energy related issues are discussed pertaining to building envelope and orientation as well as electrical systems design.
Optimization of single-step tapering amplitude and energy detuning for high-gain FELs
NASA Astrophysics Data System (ADS)
Li, He-Ting; Jia, Qi-Ka
2015-01-01
We put forward a method to optimize the single-step tapering amplitude of undulator strength and initial energy tuning of electron beam to maximize the saturation power of high gain free-electron lasers (FELs), based on the physics of longitudinal electron beam phase space. Using the FEL simulation code GENESIS, we numerically demonstrate the accuracy of the estimations for parameters corresponding to the linac coherent light source and the Tesla test facility.
Optimal energy-utilization ratio for long-distance cruising of a model fish
NASA Astrophysics Data System (ADS)
Liu, Geng; Yu, Yong-Liang; Tong, Bing-Gang
2012-07-01
The efficiency of total energy utilization and its optimization for long-distance migration of fish have attracted much attention in the past. This paper presents theoretical and computational research, clarifying the above well-known classic questions. Here, we specify the energy-utilization ratio (fη) as a scale of cruising efficiency, which consists of the swimming speed over the sum of the standard metabolic rate and the energy consumption rate of muscle activities per unit mass. Theoretical formulation of the function fη is made and it is shown that based on a basic dimensional analysis, the main dimensionless parameters for our simplified model are the Reynolds number (Re) and the dimensionless quantity of the standard metabolic rate per unit mass (Rpm). The swimming speed and the hydrodynamic power output in various conditions can be computed by solving the coupled Navier-Stokes equations and the fish locomotion dynamic equations. Again, the energy consumption rate of muscle activities can be estimated by the quotient of dividing the hydrodynamic power by the muscle efficiency studied by previous researchers. The present results show the following: (1) When the value of fη attains a maximum, the dimensionless parameter Rpm keeps almost constant for the same fish species in different sizes. (2) In the above cases, the tail beat period is an exponential function of the fish body length when cruising is optimal, e.g., the optimal tail beat period of Sockeye salmon is approximately proportional to the body length to the power of 0.78. Again, the larger fish's ability of long-distance cruising is more excellent than that of smaller fish. (3) The optimal swimming speed we obtained is consistent with previous researchers’ estimations.
Optimal control of 2-wheeled mobile robot at energy performance index
NASA Astrophysics Data System (ADS)
Kaliński, Krzysztof J.; Mazur, Michał
2016-03-01
The paper presents the application of the optimal control method at the energy performance index towards motion control of the 2-wheeled mobile robot. With the use of the proposed method of control the 2-wheeled mobile robot can realise effectively the desired trajectory. The problem of motion control of mobile robots is usually neglected and thus performance of the realisation of the high level control tasks is limited.
Towards an Optimal Gradient-dependent Energy Functional of the PZ-SIC Form
Jónsson, Elvar Örn; Lehtola, Susi; Jónsson, Hannes
2015-06-01
Results of Perdew–Zunger self-interaction corrected (PZ-SIC) density functional theory calculations of the atomization energy of 35 molecules are compared to those of high-level quantum chemistry calculations. While the PBE functional, which is commonly used in calculations of condensed matter, is known to predict on average too high atomization energy (overbinding of the molecules), the application of PZ-SIC gives a large overcorrection and leads to significant underestimation of the atomization energy. The exchange enhancement factor that is optimal for the generalized gradient approximation within the Kohn-Sham (KS) approach may not be optimal for the self-interaction corrected functional. The PBEsol functional, wheremore » the exchange enhancement factor was optimized for solids, gives poor results for molecules in KS but turns out to work better than PBE in PZ-SIC calculations. The exchange enhancement is weaker in PBEsol and the functional is closer to the local density approximation. Furthermore, the drop in the exchange enhancement factor for increasing reduced gradient in the PW91 functional gives more accurate results than the plateaued enhancement in the PBE functional. A step towards an optimal exchange enhancement factor for a gradient dependent functional of the PZ-SIC form is taken by constructing an exchange enhancement factor that mimics PBEsol for small values of the reduced gradient, and PW91 for large values. The average atomization energy is then in closer agreement with the high-level quantum chemistry calculations, but the variance is still large, the F2 molecule being a notable outlier.« less
Towards an Optimal Gradient-dependent Energy Functional of the PZ-SIC Form
Jónsson, Elvar Örn; Lehtola, Susi; Jónsson, Hannes
2015-06-01
Results of Perdew–Zunger self-interaction corrected (PZ-SIC) density functional theory calculations of the atomization energy of 35 molecules are compared to those of high-level quantum chemistry calculations. While the PBE functional, which is commonly used in calculations of condensed matter, is known to predict on average too high atomization energy (overbinding of the molecules), the application of PZ-SIC gives a large overcorrection and leads to significant underestimation of the atomization energy. The exchange enhancement factor that is optimal for the generalized gradient approximation within the Kohn-Sham (KS) approach may not be optimal for the self-interaction corrected functional. The PBEsol functional, where the exchange enhancement factor was optimized for solids, gives poor results for molecules in KS but turns out to work better than PBE in PZ-SIC calculations. The exchange enhancement is weaker in PBEsol and the functional is closer to the local density approximation. Furthermore, the drop in the exchange enhancement factor for increasing reduced gradient in the PW91 functional gives more accurate results than the plateaued enhancement in the PBE functional. A step towards an optimal exchange enhancement factor for a gradient dependent functional of the PZ-SIC form is taken by constructing an exchange enhancement factor that mimics PBEsol for small values of the reduced gradient, and PW91 for large values. The average atomization energy is then in closer agreement with the high-level quantum chemistry calculations, but the variance is still large, the F_{2} molecule being a notable outlier.
The Model of Optimization of Micro Energy; HOMER: El Modelo de Optimizacin de Micro energa
Not Available
2004-05-01
HOMER, the model of optimization of micro energy, helps to disear systems out of the network and interconnected to the network. You can use HOMER to carry out the analysis to explore an extensive rank of questions of diseo. HOMER, el modelo de optimizacin de micro energa, le ayuda a disear sistemas fuera de la red e interconectados a la red. Usted puede usar HOMER para llevar a cabo el anlisis para explorar un amplio rango de preguntas de diseo.
Parameters optimization for the energy management system of hybrid electric vehicle
NASA Astrophysics Data System (ADS)
Tseng, Chyuan-Yow; Hung, Yi-Hsuan; Tsai, Chien-Hsiung; Huang, Yu-Jen
2007-12-01
Hybrid electric vehicle (HEV) has been widely studied recently due to its high potential in reduction of fuel consumption, exhaust emission, and lower noise. Because of comprised of two power sources, the HEV requires an energy management system (EMS) to distribute optimally the power sources for various driving conditions. The ITRI in Taiwan has developed a HEV consisted of a 2.2L internal combustion engine (ICE), a 18KW motor/generator (M/G), a 288V battery pack, and a continuous variable transmission (CVT). The task of the present study is to design an energy management strategy of the EMS for the HEV. Due to the nonlinear nature and the fact of unknown system model of the system, a kind of simplex method based energy management strategy is proposed for the HEV system. The simplex method is a kind of optimization strategy which is generally used to find out the optimal parameters for un-modeled systems. The way to apply the simplex method for the design of the EMS is presented. The feasibility of the proposed method was verified by perform numerical simulation on the FTP75 drive cycles.
Optimally efficient swimming in hyper-redundant mechanisms: control, design, and energy recovery.
Wiens, A J; Nahon, M
2012-12-01
Hyper-redundant mechanisms (HRMs), also known as snake-like robots, are highly adaptable during locomotion on land. Researchers are currently working to extend their capabilities to aquatic environments through biomimetic undulatory propulsion. In addition to increasing the versatility of the system, truly biomimetic swimming could also provide excellent locomotion efficiency. Unfortunately, the complexity of the system precludes the development of a functional solution to achieve this. To explore this problem, a rapid optimization process is used to generate efficient HRM swimming gaits. The low computational cost of the approach allows for multiple optimizations over a broad range of system conditions. By observing how these conditions affect optimal kinematics, a number of new insights are developed regarding undulatory swimming in robotic systems. Two key conditions are varied within the study, swimming speed and energy recovery. It is found that the swimmer mimics the speed control behaviour of natural fish and that energy recovery drastically increases the system's efficiency. Remarkably, this efficiency increase is accompanied by a distinct change in swimming kinematics. With energy recovery, the swimmer converges to a clearly anguilliform gait, without, it tends towards the carangiform mode. PMID:23135166
PSO-Based Smart Grid Application for Sizing and Optimization of Hybrid Renewable Energy Systems.
Mohamed, Mohamed A; Eltamaly, Ali M; Alolah, Abdulrahman I
2016-01-01
This paper introduces an optimal sizing algorithm for a hybrid renewable energy system using smart grid load management application based on the available generation. This algorithm aims to maximize the system energy production and meet the load demand with minimum cost and highest reliability. This system is formed by photovoltaic array, wind turbines, storage batteries, and diesel generator as a backup source of energy. Demand profile shaping as one of the smart grid applications is introduced in this paper using load shifting-based load priority. Particle swarm optimization is used in this algorithm to determine the optimum size of the system components. The results obtained from this algorithm are compared with those from the iterative optimization technique to assess the adequacy of the proposed algorithm. The study in this paper is performed in some of the remote areas in Saudi Arabia and can be expanded to any similar regions around the world. Numerous valuable results are extracted from this study that could help researchers and decision makers. PMID:27513000
PSO-Based Smart Grid Application for Sizing and Optimization of Hybrid Renewable Energy Systems
Mohamed, Mohamed A.; Eltamaly, Ali M.; Alolah, Abdulrahman I.
2016-01-01
This paper introduces an optimal sizing algorithm for a hybrid renewable energy system using smart grid load management application based on the available generation. This algorithm aims to maximize the system energy production and meet the load demand with minimum cost and highest reliability. This system is formed by photovoltaic array, wind turbines, storage batteries, and diesel generator as a backup source of energy. Demand profile shaping as one of the smart grid applications is introduced in this paper using load shifting-based load priority. Particle swarm optimization is used in this algorithm to determine the optimum size of the system components. The results obtained from this algorithm are compared with those from the iterative optimization technique to assess the adequacy of the proposed algorithm. The study in this paper is performed in some of the remote areas in Saudi Arabia and can be expanded to any similar regions around the world. Numerous valuable results are extracted from this study that could help researchers and decision makers. PMID:27513000
NASA Astrophysics Data System (ADS)
Shigenobu, Ryuto; Noorzad, Ahmad Samim; Muarapaz, Cirio; Yona, Atsushi; Senjyu, Tomonobu
2016-04-01
Distributed generators (DG) and renewable energy sources have been attracting special attention in distribution systems in all over the world. Renewable energies, such as photovoltaic (PV) and wind turbine generators are considered as green energy. However, a large amount of DG penetration causes voltage deviation beyond the statutory range and reverse power flow at interconnection points in the distribution system. If excessive voltage deviation occurs, consumer's electric devices might break and reverse power flow will also has a negative impact on the transmission system. Thus, mass interconnections of DGs has an adverse effect on both of the utility and the customer. Therefore, reactive power control method is proposed previous research by using inverters attached DGs for prevent voltage deviations. Moreover, battery energy storage system (BESS) is also proposed for resolve reverse power flow. In addition, it is possible to supply high quality power for managing DGs and BESSs. Therefore, this paper proposes a method to maintain voltage, active power, and reactive power flow at interconnection points by using cooperative controlled of PVs, house BESSs, EVs, large BESSs, and existing voltage control devices. This paper not only protect distribution system, but also attain distribution loss reduction and effectivity management of control devices. Therefore mentioned control objectives are formulated as an optimization problem that is solved by using the Particle Swarm Optimization (PSO) algorithm. Modified scheduling method is proposed in order to improve convergence probability of scheduling scheme. The effectiveness of the proposed method is verified by case studies results and by using numerical simulations in MATLAB®.
[The ginseng growing district, taxation and trade in ancient Korea].
Yang, Jeong-Pil; Yeo, In-Sok
2004-12-01
The very first record of ginseng in the Korean peninsula dates back to early 6th century A.D., with its concentration in Chinese sources. Regardless of the fact that the Korean ginseng was introduced to China before th birth of CHrist, there is no writing about it for 500 years. This is because the Chinese substituted Korean ginseng for the Chinese one, which was cultivated around the Shangdang Area. The ginseng, however, is greatly influenced by natural environment and its native area bing Manchurian and the Korean peninsula. It is believed that ginseng range from the northern mountains of Pyongando and Hamkyongdo provincnes to the southern Taebaek and Sobaek mountains in Korea. Especially the area of Madasan(Baekdusan?) mountain was well-known for ginseng-growing district. The ginseng taxation of the Three Kingdoms period seems to have gone through certain changes along the development stages of the ancient state. The first taxation stage is estimated to be in the form of a tribute. Afterwards, as the governing power of central government was gradually strengthened in the subjugated places, there was a major replacement from tributary form to actual goods levy. The actual areas of such tributary collection is unknown, but the Sejongshilok Chiriji (geographical records of Sejong chronicles) of the early Choson ear indicates 113 prefectures and countries as those which submit ginseng to the central government. These administrations provide permissible clues to the historic background of ginseng-taxed regions of the Three Kingdoms. The ginseng trade also is estimated to have flourished in ancient Korea through the Han commanderies of China. However, the writings of Korean ginseng trade is non-existent until 6th century A.D.. Such phenomenon can be attributed to few reasons. First, the Chinese took little interest in Korean ginseng as they believed they had their own native ginseng in China. Second, same ignorance resulted from its inflowing but new feature. Third
Routing-Aware Query Optimization for Conserving Energy in Wireless Sensor Networks
NASA Astrophysics Data System (ADS)
Yang, Jie; Wang, Jie
Processing multiple real-time queries on a multi-hop wireless sensor network while conserving energy is a challenging issue. A naive approach would simply disseminate each query individually, even if the queries contain overlapping information. This imposes excessive energy consumption on sensor nodes in the data paths. We propose a routing-aware query optimization method to conserve energy on these nodes. In particular, we devise an algorithm to reduce query redundancy based on location information, attributes, and time constraints contained in the queries and the routing information of the underlying network. Our simulation results show that our approach can significantly reduce energy consumptions and improve the overall performance of the network.
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
NASA Astrophysics Data System (ADS)
Douvartzides, S. L.; Coutelieris, F. A.; Tsiakaras, P. E.
An energy-exergy analysis was undertaken in order to optimize the operational conditions of a SOFC-based power plant fueled by ethanol. A certain plant configuration was contemplated, equipped with an external steam reformer, an afterburner, a mixer and two heat exchangers (preheaters). The most significant operational parameters are enunciated and their influence on the energy and exergy balances of the plant is discussed and optimized. An optimization strategy is presented and optimally controlled unit operations are specified through minimization and allocation of exergy costs.
Pereira, Ana I.; Lima, José; Costa, Paulo
2015-03-10
There are several approaches to create the Humanoid robot gait planning. This problem presents a large number of unknown parameters that should be found to make the humanoid robot to walk. Optimization in simulation models can be used to find the gait based on several criteria such as energy minimization, acceleration, step length among the others. The energy consumption can also be reduced with elastic elements coupled to each joint. The presented paper addresses an optimization method, the Stretched Simulated Annealing, that runs in an accurate and stable simulation model to find the optimal gait combined with elastic elements. Final results demonstrate that optimization is a valid gait planning technique.
Taxation as metaphor. The hospital and public responsibility.
Friedman, E
1992-01-01
In the debate over the tax status of voluntary hospitals, most hospital executives and trustees do not seem to comprehend--or want to comprehend--the underlying issues. First, the terror of being associated with a tax hike has led many politicians to seek other "revenue enhancements" that are more ingenious than they are honest. On the other hand, many of these governments have legitimate financial problems and are seeking new sources of revenue. A second, related issue is uncertainty over what should be done about the uninsured and Medicaid populations. In the absence of an acceptable solution, we will continue to provide direct public support to public hospitals and indirect public support to private providers--including charitable tax exemptions. The third underlying issue is hospitals' curiously narrow view of their private-sector status. Most of the functions hospitals provide are not only publicly funded; they are, in fact, public functions. Finally, hospitals believe they are inherently moral organizations because they provide an inherently moral service. But hospitals grew to their present role in society almost by accident; their services are neither unique nor ethically superior. It is in how hospitals provide care that their morality can be measured, not in the fact that they provide some kind of care to somebody. An honest appraisal of these issues will help each hospital answer the basic question: As an ethical and moral matter, should this organization be paying taxes? But is this fight really about taxes? I believe society and government are using taxation as a metaphor for trust in hospitals. PMID:10115599
Quintana, Naira; Van der Kooy, Frank; Van de Rhee, Miranda D; Voshol, Gerben P; Verpoorte, Robert
2011-08-01
The need to develop and improve sustainable energy resources is of eminent importance due to the finite nature of our fossil fuels. This review paper deals with a third generation renewable energy resource which does not compete with our food resources, cyanobacteria. We discuss the current state of the art in developing different types of bioenergy (ethanol, biodiesel, hydrogen, etc.) from cyanobacteria. The major important biochemical pathways in cyanobacteria are highlighted, and the possibility to influence these pathways to improve the production of specific types of energy forms the major part of this review. PMID:21691792
Energy-scales convergence for optimal and robust quantum transport in photosynthetic complexes
Mohseni, M.; Shabani, A.; Lloyd, S.; Rabitz, H.
2014-01-21
Underlying physical principles for the high efficiency of excitation energy transfer in light-harvesting complexes are not fully understood. Notably, the degree of robustness of these systems for transporting energy is not known considering their realistic interactions with vibrational and radiative environments within the surrounding solvent and scaffold proteins. In this work, we employ an efficient technique to estimate energy transfer efficiency of such complex excitonic systems. We observe that the dynamics of the Fenna-Matthews-Olson (FMO) complex leads to optimal and robust energy transport due to a convergence of energy scales among all important internal and external parameters. In particular, we show that the FMO energy transfer efficiency is optimum and stable with respect to important parameters of environmental interactions including reorganization energy λ, bath frequency cutoff γ, temperature T, and bath spatial correlations. We identify the ratio of k{sub B}λT/ℏγg as a single key parameter governing quantum transport efficiency, where g is the average excitonic energy gap.
SU-E-T-498: Energy Minimization and Dose-Volume Inverse Optimization in Prostate Cancer
Mihaylov, I; Moros, E
2014-06-01
Purpose: To compare dose-volume (DVH) and energy minimization-based (EM) optimization for prostate cancer cases. Methods: A dozen of prostate plans were retrospectively studied. For each case two IMRT plans were generated, one with DVH and the other with EM objective cost function. Those different objective functions were used only for the organs at risk (OARs), while target objectives were achieved through DVH cost functions. The plans used the same beam angles, maximum number of segments per plan, minimum segment area and MUs per segment. Both plans were normalized such that 95% of the PTV was covered by the same prescription dose. After prescription was achieved, doses to the OARs were iteratively lowered until the standard deviation of the dose across the PTV was ~3.5%. Plan quality was evaluated by several dose indices (DIs). A DI represents the dose delivered to certain volume of a structure. Tallied DIs were for rectum and bladder 10%, 40%, 60% volumes, and 1% volumes of the femoral heads as surrogate for maximum doses. Statistical significance in the differences among DIs was quantified with two-tailed paired t-tests. Results: On average EM plans performed better than DVH plans. Statistically significant dose reduction in rectum DI10, DI40, and DI60, were 2.6%, 25.7%, and 35.9%, respectively. For bladder DI10, DI40, and DI60 the differences were 1.1%, 20.8%, and 29.7%. Left and right femoral head DI1s were better by 33.8% and 27.8% in EM plans. The quoted dose reduction is with respect to EM absolute doses for the DIs. Conclusion: The performance of EM optimization with respect to DVH optimization is patient and DI dependent. While in some cases specific DIs were better with DVH optimization, on average the energy minimization allows better (ranging from 1% to ~40%) OAR sparing than DVH optimization. NIH-NCI.
Radius exponent in elastic and rigid arterial models optimized by the least energy principle
Nakamura, Yoshihiro; Awa, Shoichi
2014-01-01
Abstract It was analyzed in normal physiological arteries whether the least energy principle would suffice to account for the radius exponent x. The mammalian arterial system was modeled as two types, the elastic or the rigid, to which Bernoulli's and Hagen‐Poiseuille's equations were applied, respectively. We minimized the total energy function E, which was defined as the sum of kinetic, pressure, metabolic and thermal energies, and loss of each per unit time in a single artery transporting viscous incompressible blood. Assuming a scaling exponent α between the vessel radius (r) and length (l) to be 1.0, x resulted in 2.33 in the elastic model. The rigid model provided a continuously changing x from 2.33 to 3.0, which corresponded to Uylings’ and Murray's theories, respectively, through a function combining Reynolds number with a proportional coefficient of the l − r relationship. These results were expanded to an asymmetric arterial fractal tree with the blood flow preservation rule. While x in the optimal elastic model accounted for around 2.3 in proximal systemic (r >1 mm) and whole pulmonary arteries (r ≥0.004 mm), optimal x in the rigid model explained 2.7 in elastic‐muscular (0.1 < r ≤1 mm) and 3.0 in peripheral resistive systemic arteries (0.004 ≤ r ≤0.1 mm), in agreement with data obtained from angiographic, cast‐morphometric, and in vivo experimental studies in the literature. The least energy principle on the total energy basis provides an alternate concept of optimality relating to mammalian arterial fractal dimensions under α = 1.0. PMID:24744905
The importance of geospatial data to calculate the optimal distribution of renewable energies
NASA Astrophysics Data System (ADS)
Díaz, Paula; Masó, Joan
2013-04-01
Specially during last three years, the renewable energies are revolutionizing the international trade while they are geographically diversifying markets. Renewables are experiencing a rapid growth in power generation. According to REN21 (2012), during last six years, the total renewables capacity installed grew at record rates. In 2011, the EU raised its share of global new renewables capacity till 44%. The BRICS nations (Brazil, Russia, India and China) accounted for about 26% of the total global. Moreover, almost twenty countries in the Middle East, North Africa, and sub-Saharan Africa have currently active markets in renewables. The energy return ratios are commonly used to calculate the efficiency of the traditional energy sources. The Energy Return On Investment (EROI) compares the energy returned for a certain source and the energy used to get it (explore, find, develop, produce, extract, transform, harvest, grow, process, etc.). These energy return ratios have demonstrated a general decrease of efficiency of the fossil fuels and gas. When considering the limitations of the quantity of energy produced by some sources, the energy invested to obtain them and the difficulties of finding optimal locations for the establishment of renewables farms (e.g. due to an ever increasing scarce of appropriate land) the EROI becomes relevant in renewables. A spatialized EROI, which uses variables with spatial distribution, enables the optimal position in terms of both energy production and associated costs. It is important to note that the spatialized EROI can be mathematically formalized and calculated the same way for different locations in a reproducible way. This means that having established a concrete EROI methodology it is possible to generate a continuous map that will highlight the best productive zones for renewable energies in terms of maximum energy return at minimum cost. Relevant variables to calculate the real energy invested are the grid connections between
NASA Astrophysics Data System (ADS)
Salter, Bill Jean, Jr.
Purpose. The advent of new, so called IVth Generation, external beam radiation therapy treatment machines (e.g. Scanditronix' MM50 Racetrack Microtron) has raised the question of how the capabilities of these new machines might be exploited to produce extremely conformal dose distributions. Such machines possess the ability to produce electron energies as high as 50 MeV and, due to their scanned beam delivery of electron treatments, to modulate intensity and even energy, within a broad field. Materials and methods. Two patients with 'challenging' tumor geometries were selected from the patient archives of the Cancer Therapy and Research Center (CTRC), in San Antonio Texas. The treatment scheme that was tested allowed for twelve, energy and intensity modulated beams, equi-spaced about the patient-only intensity was modulated for the photon treatment. The elementary beams, incident from any of the twelve allowed directions, were assumed parallel, and the elementary electron beams were modeled by elementary beam data. The optimal arrangement of elementary beam energies and/or intensities was optimized by Szu-Hartley Fast Simulated Annealing Optimization. Optimized treatment plans were determined for each patient using both the high energy, intensity and energy modulated electron (HIEME) modality, and the 6 MV photon modality. The 'quality' of rival plans were scored using three different, popular objective functions which included Root Mean Square (RMS), Maximize Dose Subject to Dose and Volume Limitations (MDVL - Morrill et. al.), and Probability of Uncomplicated Tumor Control (PUTC) methods. The scores of the two optimized treatments (i.e. HIEME and intensity modulated photons) were compared to the score of the conventional plan with which the patient was actually treated. Results. The first patient evaluated presented a deeply located target volume, partially surrounding the spinal cord. A healthy right kidney was immediately adjacent to the tumor volume, separated
NASA Astrophysics Data System (ADS)
Efstratiadis, Andreas; Tsoukalas, Ioannis; Kossieris, Panayiotis; Karavokiros, George; Christofides, Antonis; Siskos, Alexandros; Mamassis, Nikos; Koutsoyiannis, Demetris
2015-04-01
Modelling of large-scale hybrid renewable energy systems (HRES) is a challenging task, for which several open computational issues exist. HRES comprise typical components of hydrosystems (reservoirs, boreholes, conveyance networks, hydropower stations, pumps, water demand nodes, etc.), which are dynamically linked with renewables (e.g., wind turbines, solar parks) and energy demand nodes. In such systems, apart from the well-known shortcomings of water resources modelling (nonlinear dynamics, unknown future inflows, large number of variables and constraints, conflicting criteria, etc.), additional complexities and uncertainties arise due to the introduction of energy components and associated fluxes. A major difficulty is the need for coupling two different temporal scales, given that in hydrosystem modeling, monthly simulation steps are typically adopted, yet for a faithful representation of the energy balance (i.e. energy production vs. demand) a much finer resolution (e.g. hourly) is required. Another drawback is the increase of control variables, constraints and objectives, due to the simultaneous modelling of the two parallel fluxes (i.e. water and energy) and their interactions. Finally, since the driving hydrometeorological processes of the integrated system are inherently uncertain, it is often essential to use synthetically generated input time series of large length, in order to assess the system performance in terms of reliability and risk, with satisfactory accuracy. To address these issues, we propose an effective and efficient modeling framework, key objectives of which are: (a) the substantial reduction of control variables, through parsimonious yet consistent parameterizations; (b) the substantial decrease of computational burden of simulation, by linearizing the combined water and energy allocation problem of each individual time step, and solve each local sub-problem through very fast linear network programming algorithms, and (c) the substantial
NASA Astrophysics Data System (ADS)
Kojima, Sadaoki; Zhe, Zhang; Sawada, Hiroshi; Firex Team
2015-11-01
In Fast Ignition Inertial Confinement Fusion, optimization of relativistic electron beam (REB) accelerated by a high-intensity laser pulse is critical for the efficient core heating. The high-energy tail of the electron spectrum is generated by the laser interaction with a long-scale-length plasma and does not efficiently couple to a fuel core. In the cone-in-shell scheme, long-scale-length plasmas can be produced inside the cone by the pedestal of a high-intensity laser, radiation heating of the inner cone wall and shock wave from an implosion core. We have investigated a relation between the presence of pre-plasma inside the cone and the REB energy distribution using the Gekko XII and 2kJ-PW LFEX laser at the Institute of Laser Engineering. The condition of an inner cone wall was monitored using VISAR and SOP systems on a cone-in-shell implosion. The generation of the REB was measured with an electron energy analyzer and a hard x-ray spectrometer on a separate shot by injecting the LFEX laser in an imploded target. The result shows the strong correlation between the preheat and high-energy tail generation. Optimization of cone-wall thickness for the fast-ignition will be discussed. This work is supported by NIFS, MEXT/JSPS KAKENHI Grant and JSPS Fellows (Grant Number 14J06592).
Combined Municipal Solid Waste and biomass system optimization for district energy applications
Rentizelas, Athanasios A. Tolis, Athanasios I. Tatsiopoulos, Ilias P.
2014-01-15
Highlights: • Combined energy conversion of MSW and agricultural residue biomass is examined. • The model optimizes the financial yield of the investment. • Several system specifications are optimally defined by the optimization model. • The application to a case study in Greece shows positive financial yield. • The investment is mostly sensitive on the interest rate, the investment cost and the heating oil price. - Abstract: Municipal Solid Waste (MSW) disposal has been a controversial issue in many countries over the past years, due to disagreement among the various stakeholders on the waste management policies and technologies to be adopted. One of the ways of treating/disposing MSW is energy recovery, as waste is considered to contain a considerable amount of bio-waste and therefore can lead to renewable energy production. The overall efficiency can be very high in the cases of co-generation or tri-generation. In this paper a model is presented, aiming to support decision makers in issues relating to Municipal Solid Waste energy recovery. The idea of using more fuel sources, including MSW and agricultural residue biomass that may exist in a rural area, is explored. The model aims at optimizing the system specifications, such as the capacity of the base-load Waste-to-Energy facility, the capacity of the peak-load biomass boiler and the location of the facility. Furthermore, it defines the quantity of each potential fuel source that should be used annually, in order to maximize the financial yield of the investment. The results of an energy tri-generation case study application at a rural area of Greece, using mixed MSW and biomass, indicate positive financial yield of investment. In addition, a sensitivity analysis is performed on the effect of the most important parameters of the model on the optimum solution, pinpointing the parameters of interest rate, investment cost and heating oil price, as those requiring the attention of the decision makers
Optimal capacity of the battery energy storage system in a power system
Tsungying Lee; Nanming Chen
1993-12-01
Due to the cyclical human life, utility loads appear to be cyclical too. During daytime when most factories are in operation, the electricity demand is very high. On the contrary, when most people are sleeping from midnight to daybreak, the electric load is very low, usually only half of the peak load amount. To meet this large gap between peak load and light load, utilities must idle many generation plants during light load period while operating all generation plants during peak load period no matter how expensive they are. This low utilization factor of generation plants and uneconomical operation have sparked utilities to invest in energy storage devices such as pumped storage plants, compressed air energy storage plants, battery energy storage systems (BES) and superconducting magnetic energy storage systems (SMES) etc. Among these, pumped storage is already commercialized and is the most widely used device. However, it suffers the limit of available sites and will be saturated in the future. Other energy storage devices are still under research to reduce the cost. This paper investigates the optimal capacity of the battery energy storage system in a power system. Taiwan Power Company System is used as the example system to test this algorithm. Results show that the maximum economic benefit of the battery energy storage in a power system can be achieved by this algorithm.
Network design optimization of fuel cell systems and distributed energy devices.
Colella, Whitney G.
2010-07-01
This research explores the thermodynamics, economics, and environmental impacts of innovative, stationary, polygenerative fuel cell systems (FCSs). Each main report section is split into four subsections. The first subsection, 'Potential Greenhouse Gas (GHG) Impact of Stationary FCSs,' quantifies the degree to which GHG emissions can be reduced at a U.S. regional level with the implementation of different FCS designs. The second subsection, 'Optimizing the Design of Combined Heat and Power (CHP) FCSs,' discusses energy network optimization models that evaluate novel strategies for operating CHP FCSs so as to minimize (1) electricity and heating costs for building owners and (2) emissions of the primary GHG - carbon dioxide (CO{sub 2}). The third subsection, 'Optimizing the Design of Combined Cooling, Heating, and Electric Power (CCHP) FCSs,' is similar to the second subsection but is expanded to include capturing FCS heat with absorptive cooling cycles to produce cooling energy. The fourth subsection, - Thermodynamic and Chemical Engineering Models of CCHP FCSs,' discusses the physics and thermodynamic limits of CCHP FCSs.
NASA Astrophysics Data System (ADS)
Palagummi, S.; Yuan, F. G.
2015-04-01
A detailed analysis of a mono-stable vertical diamagnetic levitation (VDL) system for optimal vibration energy harvesting is presented. Initial studies showed that simple analytical techniques such as the dipole model and the image method provide useful guideline for understanding the potential of a diamagnetic levitation system, however, it is discussed here that the more accurate semi-analytical techniques such as the thin coil model and the discrete volume method are needed for quantitative optimization and design of the VDL system. With the semi-analytical techniques, the influence of the cylindrical geometry of the floating magnet, the lifting magnet and the diamagnetic plate are parametrically studied to assess their effects on the levitation gap, size of the system and the natural frequency. For efficient vibration energy harvesting using the VDL system, ways to mitigate eddy current damping and a coil geometry for transduction are critically discussed. With the optimized parameters, an experimental system is realized which showed a hardening type nonlinearity. The results show an overall efficiency of 1.54 percent, a root mean square (rms) power output of 1.72 μW when excited at a peak acceleration of 0.081 m/s2 and at a frequency of 2.1 Hz.
NASA Astrophysics Data System (ADS)
Zhang, Dingcheng; Yu, Dejie; Zhang, Wenyi
2015-11-01
Compound faults diagnosis is a challenge for rotating machinery fault diagnosis. The vibration signals measured from gearboxes are usually complex, non-stationary, and nonlinear. When compound faults occur in a gearbox, weak fault characteristic signals are always submerged by the strong ones. Therefore, it is difficult to detect a weak fault by using the demodulating analysis of vibration signals of gearboxes directly. The key to compound faults diagnosis of gearboxes is to separate different fault characteristic signals from the collected vibration signals. Aiming at that problem, a new method for the compound faults diagnosis of gearboxes is proposed based on the energy operator demodulating of optimal resonance components. In this method, the genetic algorithm is first used to obtain the optimal decomposition parameters. Then the compound faults vibration signals of a gearbox are subject to resonance-based signal sparse decomposition (RSSD) to separate the fault characteristic signals of the gear and the bearing by using the optimal decomposition parameters. Finally, the separated fault characteristic signals are analyzed by energy operator demodulating, and each one’s instantaneous amplitude can be calculated. According to the spectra of instantaneous amplitudes of fault characteristic signals, the faults of the gear and the bearing can be diagnosed, respectively. The performance of the proposed method is validated by using the simulation data and the experiment vibration signals from a gearbox with compound faults.
Energy and Cost Optimized Technology Options to Meet Energy Needs of Food Processors
Makhmalbaf, Atefe; Srivastava, Viraj; Hoffman, Michael G.; Wagner, Anne W.; Thornton, John
2015-05-01
Full Paper Submission for: Combined cooling, heating and electric power (CCHP) distributed generation (DG) systems can provide electric power and, heating and cooling capability to commercial and industrial facilities directly onsite, while increasing energy efficiency, security of energy supply, grid independence and enhancing the environmental and economic situation for the site. Food processing industries often have simultaneous requirements for heat, steam, chilling and electricity making them well suited for the use of such systems to supply base-load or as peak reducing generators enabling reduction of overall energy use intensity. This paper documents analysis from a project evaluating opportunities enabled by CCHPDG for emission and cost reductions and energy storage systems installed onsite at food processing facilities. In addition, this distributed generation coupled with energy storage demonstrates a non-wires solution to delay or eliminate the need for upgrades to electric distribution systems. It was found that a dairy processing plant in the Pacific Northwest currently purchasing 15,000 MWh/yr of electricity and 190,000 MMBtu/yr of gas could be provided with a 1.1 MW CCHP system reducing the amount of electric power purchased to 450 MWh/yr while increasing the gas demand to 255,000 MMBtu/yr. The high percentage of hydro-power in this region resulted in CO2 emissions from CCHP to be higher than that attributed to the electric utility/regional energy mix. The value of this work is in documenting a real-world example demonstrating the value of CCHP to facility owners and financial decision makers to encourage them to more seriously consider CCHP systems when building or upgrading facilities.
Optimal design of force magnification frame of a piezoelectric stack energy harvester
NASA Astrophysics Data System (ADS)
Chen, Shubin; Wang, Lirong; Zhou, Wanlu; Musgrave, Patrick; Xu, Tian-Bing; Zuo, Lei
2015-04-01
With the rapid development of portable electrical devices, the demand for batteries to power these portable devices increases dramatically. However, the development of the battery technology is slow in energy storage capability and cannot meet such requirements. This paper proposed an optimal frame design for a kind of portable piezoelectric stack energy harvesters, with large force magnification ratio and high energy transmission ratio. Two kinds of design approaches have been studied and explored, i.e., flexure compliant mechanism math based and finite element analysis (FEA) based. Prototypes are fabricated and assembled. Experiments with both static test and dynamic test have been conducted to approve the effectiveness of the proposed design. The measured force magnification ratio of 6.13 times and 21.8 times for the first-stage harvester and the dual-stage harvester are close to the design objective of 7.17 times and 24.4 times. The designed single stage harvester can generate 20.7mW/g2 at resonance frequency of 160Hz with optimal resistance of 393Ω under 0.8g base excitation with 100gram top mass, and the dual stage harvester has power generation of 487mW/g2 at resonance frequency of 38.9Hz with optimal resistance of 818Ω under 1.94g base excitation with 100gram top mass. The proposed two-stage PZT energy harvester can be used to develop portable power regenerator to compensate the urgent battery needs in remote area for both civic and military application.
Topology optimization and fabrication of low frequency vibration energy harvesting microdevices
NASA Astrophysics Data System (ADS)
Deng, Jiadong; Rorschach, Katherine; Baker, Evan; Sun, Cheng; Chen, Wei
2015-02-01
Topological design of miniaturized resonating structures capable of harvesting electrical energy from low frequency environmental mechanical vibrations encounters a particular physical challenge, due to the conflicting design requirements: low resonating frequency and miniaturization. In this paper structural static stiffness to resist undesired lateral deformation is included into the objective function, to prevent the structure from degenerating and forcing the solution to be manufacturable. The rational approximation of material properties interpolation scheme is introduced to deal with the problems of local vibration and instability of the low density area induced by the design dependent body forces. Both density and level set based topology optimization (TO) methods are investigated in their parameterization, sensitivity analysis, and applicability for low frequency energy harvester TO problems. Continuum based variation formulations for sensitivity analysis and the material derivative based shape sensitivity analysis are presented for the density method and the level set method, respectively; and their similarities and differences are highlighted. An external damper is introduced to simulate the energy output of the resonator due to electrical damping and the Rayleigh proportional damping is used for mechanical damping. Optimization results for different scenarios are tested to illustrate the influences of dynamic and static loads. To demonstrate manufacturability, the designs are built to scale using a 3D microfabrication method and assembled into vibration energy harvester prototypes. The fabricated devices based on the optimal results from using different TO techniques are tested and compared with the simulation results. The structures obtained by the level set based TO method require less post-processing before fabrication and the structures obtained by the density based TO method have resonating frequency as low as 100 Hz. The electrical voltage response
NASA Astrophysics Data System (ADS)
Lassonde, Sylvain; Boucher, Olivier; Breon, François-Marie; Tobin, Isabelle; Vautard, Robert
2016-04-01
The share of renewable energies in the mix of electricity production is increasing worldwide. This trend is driven by environmental and economic policies aiming at a reduction of greenhouse gas emissions and an improvement of energy security. It is expected to continue in the forthcoming years and decades. Electricity production from renewables is related to weather and climate factors such as the diurnal and seasonal cycles of sunlight and wind, but is also linked to variability on all time scales. The intermittency in the renewable electricity production (solar, wind power) could eventually hinder their future deployment. Intermittency is indeed a challenge as demand and supply of electricity need to be balanced at any time. This challenge can be addressed by the deployment of an overcapacity in power generation (from renewable and/or thermal sources), a large-scale energy storage system and/or improved management of the demand. The main goal of this study is to optimize a hypothetical renewable energy system at the French and European scales in order to investigate if spatial diversity of the production (here electricity from wind energy) could be a response to the intermittency. We use ECMWF (European Centre for Medium-Range Weather Forecasts) ERA-interim meteorological reanalysis and meteorological fields from the Weather Research and Forecasts (WRF) model to estimate the potential for wind power generation. Electricity demand and production are provided by the French electricity network (RTE) at the scale of administrative regions for years 2013 and 2014. Firstly we will show how the simulated production of wind power compares against the measured production at the national and regional scale. Several modelling and bias correction methods of wind power production will be discussed. Secondly, we will present results from an optimization procedure that aims to minimize some measure of the intermittency of wind energy. For instance we estimate the optimal
An efficient algorithm for energy gradients and orbital optimization in valence bond theory.
Song, Lingchun; Song, Jinshuai; Mo, Yirong; Wu, Wei
2009-02-01
An efficient algorithm for energy gradients in valence bond theory with nonorthogonal orbitals is presented. A general Hartree-Fock-like expression for the Hamiltonian matrix element between valence bond (VB) determinants is derived by introducing a transition density matrix. Analytical expressions for the energy gradients with respect to the orbital coefficients are obtained explicitly, whose scaling for computational cost is m(4), where m is the number of basis functions, and is thus approximately the same as in HF method. Compared with other existing approaches, the present algorithm has lower scaling, and thus is much more efficient. Furthermore, the expression for the energy gradient with respect to the nuclear coordinates is also presented, and it provides an effective algorithm for the geometry optimization and the evaluation of various molecular properties in VB theory. Test applications show that our new algorithm runs faster than other methods. PMID:18629879
Rosenbaum, Gerd; Ginell, Stephan L.; Chen, Julian C.-H.
2015-01-01
In this study, a practical method for operating existing undulator synchrotron beamlines at photon energies considerably higher than their standard operating range is described and applied at beamline 19-ID of the Structural Biology Center at the Advanced Photon Source enabling operation at 30 keV. Adjustments to the undulator spectrum were critical to enhance the 30 keV flux while reducing the lower- and higher-energy harmonic contamination. A Pd-coated mirror and Al attenuators acted as effective low- and high-bandpass filters. The resulting flux at 30 keV, although significantly lower than with X-ray optics designed and optimized for this energy, allowed for accurate data collection on crystals of the small protein crambin to 0.38 Å resolution.
Rosenbaum, Gerd; Ginell, Stephan L.; Chen, Julian C.-H.
2015-01-01
In this study, a practical method for operating existing undulator synchrotron beamlines at photon energies considerably higher than their standard operating range is described and applied at beamline 19-ID of the Structural Biology Center at the Advanced Photon Source enabling operation at 30 keV. Adjustments to the undulator spectrum were critical to enhance the 30 keV flux while reducing the lower- and higher-energy harmonic contamination. A Pd-coated mirror and Al attenuators acted as effective low- and high-bandpass filters. The resulting flux at 30 keV, although significantly lower than with X-ray optics designed and optimized for this energy, allowed for accuratemore » data collection on crystals of the small protein crambin to 0.38 Å resolution.« less
Application of Optimal Production Control theory for Home Energy Management in a Micro Grid
Malikopoulos, Andreas; Djouadi, Seddik M; Kuruganti, Teja
2016-01-01
We consider the optimal stochastic control problem for home energy systems with solar and energy storage devices when the demand is realized from the grid. The demand is subject to Brownian motions with both drift and variance parameters modulated by a continuous-time Markov chain that represents the regime of electricity price. We model the systems as pure stochastic differential equation models, and then we follow the completing square technique to solve the stochastic home energy management problem. The effectiveness of the efficiency of the proposed approach is validated through a simulation example. For practical situations with constraints consistent to those studied here, our results imply the proposed framework could reduce the electricity cost from short-term purchase in peak hour market.
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.
Design and optimization of an RF energy harvesting system from multiple sources
NASA Astrophysics Data System (ADS)
Ali, Mai; Albasha, Lutfi; Qaddoumi, Nasser
2013-05-01
This paper presents the design and optimization of an RF energy harvesting system from multiple sources. The RF power is harvested from four frequency bands representing five wireless systems, namely GSM, UMTS, DTV, Wi-Fi, and road tolling system. A Schottky diode model was developed based on which an RF-DC rectifier joined with a voltage multiplier circuits were designed. The simulation results of the complete RF harvesting system showed superior performance to similar state of the art systems. To further optimize the design, and to eliminate use of a non-standard CMOS process associated with Schottky diodes, the Schottky diode based rectifier was replaced by diode connected transistor configuration based on self-threshold cancellation (SVC) technique.
Liu, Guodong; Ceylan, Oguzhan; Xu, Yan; Tomsovic, Kevin
2015-01-01
With increasing penetration of distributed generation in the distribution networks (DN), the secure and optimal operation of DN has become an important concern. In this paper, an iterative quadratic constrained quadratic programming model to minimize voltage deviations and maximize distributed energy resource (DER) active power output in a three phase unbalanced distribution system is developed. The optimization model is based on the linearized sensitivity coefficients between controlled variables (e.g., node voltages) and control variables (e.g., real and reactive power injections of DERs). To avoid the oscillation of solution when it is close to the optimum, a golden search method is introduced to control the step size. Numerical simulations on modified IEEE 13 nodes test feeders show the efficiency of the proposed model. Compared to the results solved by heuristic search (harmony algorithm), the proposed model converges quickly to the global optimum.
Energy and Cost Optimized Technology Options to Meet Energy Needs of Food Processors
Makhmalbaf, Atefe; Srivastava, Viraj; Hoffman, Michael G.; Wagner, Anne W.; Thornton, John
2015-04-02
ABSTRACT Combined cooling, heating and electric power (CCHP) distributed generation (DG) systems can provide electricity, heat, and cooling power to buildings and industrial processes directly onsite, while significantly increasing energy efficiency, security of energy supply, and grid independence. Fruit, vegetable, dairy and meat processing industries with simultaneous requirements for heat, steam, chilling and electricity, are well suited for the use of such systems to supply base-load electrical demand or as peak reducing generators with heat recovery in the forms of hot water, steam and/or chilled water. This paper documents results and analysis from a pilot project to evaluate opportunities for energy, emission, and cost for CCHP-DG and energy storage systems installed onsite at food processing facilities. It was found that a dairy processing plant purchasing 15,000 MWh of electricity will need to purchase 450 MWh with the integration of a 1.1 MW CCHP system. Here, the natural gas to be purchased increased from 190,000 MMBtu to 255,000 MMBtu given the fuel requirements of the CCHP system. CCHP systems lower emissions, however, in the Pacific Northwest the high percentage of hydro-power results in CO2 emissions from CCHP were higher than that attributed to the electric utility/regional energy mix. The value of this paper is in promoting and educating financial decision makers to seriously consider CCHP systems when building or upgrading facilities. The distributed generation aspect can reduce utility costs for industrial facilities and show non-wires solution benefits to delay or eliminate the need for upgrades to local electric transmission and distribution systems.
Fujino, Yoshihisa; Tanaka, Ryuichi; Kubo, Tatsuhiko; Matsuda, Shinya
2013-01-01
Background This cohort study examined the association between taxation categories of long-term care insurance premiums and survival among elderly Japanese. Methods A total of 3000 participants aged 60 years or older were randomly recruited in Y City, Japan in 2002, of whom 2964 provided complete information for analysis. Information on income level, mobility status, medical status, and vital status of each participant was collected annually from 2002 to 2006. Follow-up surveys on survival were conducted until August 2007. Hazard ratios (HRs) were estimated by a Cox model, using taxation categories at baseline. In these analyses, age-adjusted and age- and mobility-adjusted models were used. Results A significantly higher mortality risk was seen only in the lowest taxation category among men: as compared with men in the second highest taxation category, the HR in the lowest category was 2.53 (95% CI, 1.26–5.08, P = 0.009). This significant association between taxation category and mortality was lost after adjustment for mobility. There was no other difference in mortality among taxation categories in men or women. Conclusions The present findings only partly supported our hypothesis that taxation category is a good indicator of socioeconomic status in examining health inequalities among elderly Japanese. PMID:23258217
Dynamic optimization for commercialization of renewable energy: an example for solar photovoltaics
Richards, Kenneth, R.; Ashton, W. Bradley; McVeigh, James
2000-04-21
There are several studies of optimal allocation of research and development resources over the time horizon of a project. The primary result of the basic noncompetitive models in this literature is that the optimal strategy is to choose a research intensity and ending date for the project such that the marginal costs of accelerating the project equals the marginal benefits of introducing the product sooner. This literature provides useful insights for the government planner who must allocate R&D resources for renewable energy development. However, several characteristics distinguish the process from the typical R&D planning problem. Specifically, with PV development, where the goal is to maximize the net present value of activities leading to cost reduction in commercial modules, there are (1) significant lag-times between investment in laboratory research and resulting effects in the marketplace, (2) a learning curve associated with the manufacturing process that also reduces the cost s of PV modules, (3) interim benefits from technical advances, (4) no clear end point to the R&D process, but rather a tapering off of the value of advances in technical efficiency, (5) significant uncertainty in the R&D process, (6) a family of products rather than an individual technology, (7) a co-mingling of government and private resources with implications for efficient management. A dynamic model is developed to characterize the optimal intensity and timing of government and private resource allocation for basic research in improving the technical efficiency of cells and subsidies to the manufacturing process to encourage progress on the learning curve. A series of propositions regarding optimal paths for each are examined. While the research is purely analytical, the results are useful for conceptualizing the R&D planning process. They also provide a basis for a numerical study that can address whether current levels and historic patterns of funding are optimal.
Yao, Yanyan; Jiang, Tao; Zhang, Limin; Chen, Xiangyu; Gao, Zhenliang; Wang, Zhong Lin
2016-08-24
Ocean waves are one of the most promising renewable energy sources for large-scope applications due to the abundant water resources on the earth. Triboelectric nanogenerator (TENG) technology could provide a new strategy for water wave energy harvesting. In this work, we investigated the charging characteristics of utilizing a wavy-structured TENG to charge a capacitor under direct water wave impact and under enclosed ball collision, by combination of theoretical calculations and experimental studies. The analytical equations of the charging characteristics were theoretically derived for the two cases, and they were calculated for various load capacitances, cycle numbers, and structural parameters such as compression deformation depth and ball size or mass. Under the direct water wave impact, the stored energy and maximum energy storage efficiency were found to be controlled by deformation depth, while the stored energy and maximum efficiency can be optimized by the ball size under the enclosed ball collision. Finally, the theoretical results were well verified by the experimental tests. The present work could provide strategies for improving the charging performance of TENGs toward effective water wave energy harvesting and storage. PMID:27491727
Optimizing the CsI thickness for chest dual-shot dual-energy detectors
NASA Astrophysics Data System (ADS)
Kim, Dong Woon; Kim, Junwoo; Youn, Hanbean; Jeon, Hosang; Kim, Ho Kyung
2016-03-01
Dual-energy imaging method has been introduced to improve conspicuity of abnormalities in radiographs. The method typically uses the fast kilovoltage-switching approach, which acquires low and high-energy projections in successive x-ray exposures with the same detector. However, it is typically known that there exists an optimal detector thickness regarding specific imaging tasks or energies used. In this study, the dual-energy detectability has been theoretically addressed for various combinations of detector thicknesses for low and high-energy spectra using the cascaded-systems analysis. Cesium iodide (CsI) is accounted for the x-ray converter in the hypothetical detector. The simple prewhitening model shows that a larger CsI thickness (250 mg cm-2 for example) would be preferred to the the typical CsI thickness of 200 mg cm-2 for better detectability. On the other hand, the typical CsI thickness is acceptable for the prewhitening model considering human-eye filter. The theoretical strategy performed in this study will be useful for a better design of detectors for dual-energy imaging.
NASA Astrophysics Data System (ADS)
Gilau, Asmerom M.
This dissertation addresses two distinct objectives; designing cost-effective renewable energy powered projects including seawater reverse osmosis (SWRO), aquaculture, and ice-making plant, and analyzing the cost-effectiveness of these projects in achieving low abatement costs and promoting sustainable developments under the Clean Development Mechanism. The results of SWRO analysis show that a wind powered system is the least expensive and a PV powered system the most expensive, with finished water costs of about 0.50 /m3 and 1.00 /m3, respectively. By international standards, these costs are competitive. The results of renewable energy powered commercial tilapia production indicate that a wind-diesel system has high potential for intensive tilapia production as well as carbon dioxide emission reductions. The study also investigates aeration failures in renewable energy powered tilapia production systems. With respect to the ice-making plant, unlike previous studies which consider nighttime operation only, we have found that a nighttime PV powered ice-making system is more expensive (1/kWh) than daytime ice-making system (0.70/kWh). Our optimal energy options analysis at project scale which includes SWRO, ice-making plant and household energy consumption for about 100 households shows that compared to diesel only energy option, PV-D, W-D, and PV-W-D hybrids are very cost-effective energy options. Moreover, energy options with high levels of renewable energy including 100% renewables have the lowest net present cost and they are already cost-effective without CDM. On the other hand, while the removal of about 87% carbon dioxide emissions could be achieved at negative cost, initial investment could increase by a factor of 40, which is one of the primary barriers hindering wider renewable energy applications in developing countries. Thus in order to increase developing countries' participation in the carbon market, CDM policy should shift from a purely market oriented
26 CFR 1.522-2 - Manner of taxation of cooperative associations subject to section 522.
Code of Federal Regulations, 2014 CFR
2014-04-01
... provided in 26 CFR (1939) 39.22(d)-3 (Regulations 118) must exercise the election provided in section 472... THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Farmers' Cooperatives § 1.522-2 Manner of taxation of cooperative associations subject to section 522. (a) In general....
26 CFR 1.522-2 - Manner of taxation of cooperative associations subject to section 522.
Code of Federal Regulations, 2013 CFR
2013-04-01
... provided in 26 CFR (1939) 39.22(d)-3 (Regulations 118) must exercise the election provided in section 472... THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Farmers' Cooperatives § 1.522-2 Manner of taxation of cooperative associations subject to section 522. (a) In general....
26 CFR 1.522-2 - Manner of taxation of cooperative associations subject to section 522.
Code of Federal Regulations, 2012 CFR
2012-04-01
... provided in 26 CFR (1939) 39.22(d)-3 (Regulations 118) must exercise the election provided in section 472... THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Farmers' Cooperatives § 1.522-2 Manner of taxation of cooperative associations subject to section 522. (a) In general....
26 CFR 1.857-6 - Method of taxation of shareholders of real estate investment trusts.
Code of Federal Regulations, 2011 CFR
2011-04-01
... OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-6 Method of taxation of shareholders of real estate investment trusts. (a) Ordinary income... receiving dividends from a real estate investment trust shall include such dividends in gross income for...
A Graphical Exposition of the Link between Two Representations of the Excess Burden of Taxation
ERIC Educational Resources Information Center
Liu, Liqun; Rettenmaier, Andrew J.
2005-01-01
The excess burden of taxation typically has two graphical representations in undergraduate microeconomics and public finance textbooks: the IC/BC (indifference curve/budget constraint) representation and the demand/supply representation. The IC/BC representation has the advantage of showing the behavioral response to a distortionary tax and how a…
26 CFR 1.857-6 - Method of taxation of shareholders of real estate investment trusts.
Code of Federal Regulations, 2014 CFR
2014-04-01
... OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-6 Method of taxation of shareholders of real estate investment trusts. (a) Ordinary income... receiving dividends from a real estate investment trust shall include such dividends in gross income for...
26 CFR 1.857-6 - Method of taxation of shareholders of real estate investment trusts.
Code of Federal Regulations, 2012 CFR
2012-04-01
... OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-6 Method of taxation of shareholders of real estate investment trusts. (a) Ordinary income... receiving dividends from a real estate investment trust shall include such dividends in gross income for...
26 CFR 1.857-6 - Method of taxation of shareholders of real estate investment trusts.
Code of Federal Regulations, 2013 CFR
2013-04-01
... OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Real Estate Investment Trusts § 1.857-6 Method of taxation of shareholders of real estate investment trusts. (a) Ordinary income... receiving dividends from a real estate investment trust shall include such dividends in gross income for...
26 CFR 1.83-7 - Taxation of nonqualified stock options.
Code of Federal Regulations, 2011 CFR
2011-04-01
..., 2003. For transactions prior to that date, see § 1.83-7 as published in 26 CFR part 1 (revised as of... 26 Internal Revenue 2 2011-04-01 2011-04-01 false Taxation of nonqualified stock options. 1.83-7... of nonqualified stock options. (a) In general. If there is granted to an employee or...
26 CFR 1.597-2 - Taxation of Federal financial assistance.
Code of Federal Regulations, 2011 CFR
2011-04-01
... financial assistance. (a) Inclusion in income—(1) In general. Except as otherwise provided in the... 26 Internal Revenue 7 2011-04-01 2009-04-01 true Taxation of Federal financial assistance. 1.597-2...) of this section for rules regarding the timing of inclusion of certain FFA. See paragraph (d) of...
26 CFR 1.61-22 - Taxation of split-dollar life insurance arrangements.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 2 2011-04-01 2011-04-01 false Taxation of split-dollar life insurance arrangements. 1.61-22 Section 1.61-22 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-22...
26 CFR 1.61-22 - Taxation of split-dollar life insurance arrangements.
Code of Federal Regulations, 2013 CFR
2013-04-01
... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-22 Taxation of split-dollar life insurance arrangements. (a) Scope—(1) In... purposes of the income tax, the gift tax, the Federal Insurance Contributions Act (FICA), the...
26 CFR 1.61-22 - Taxation of split-dollar life insurance arrangements.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 2 2014-04-01 2014-04-01 false Taxation of split-dollar life insurance arrangements. 1.61-22 Section 1.61-22 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-22...
26 CFR 1.61-22 - Taxation of split-dollar life insurance arrangements.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 2 2012-04-01 2012-04-01 false Taxation of split-dollar life insurance arrangements. 1.61-22 Section 1.61-22 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Definition of Gross Income, Adjusted Gross Income, and Taxable Income § 1.61-22...
Uniformity of Taxation and Illinois School Funding: A State Constitutional Perspective
ERIC Educational Resources Information Center
Reynolds, Laurie
2008-01-01
The Illinois Supreme Court has permitted the General Assembly to create a system of public school funding that is widely disparate and disadvantageous to students in school districts with low-property wealth. In this Article, I argue that the court has not adequately considered the nexus between the Uniformity of Taxation provision and the…
20 CFR 209.14 - Report of separation allowances subject to tier II taxation.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Report of separation allowances subject to... separation allowances subject to tier II taxation. For any employee who is paid a separation payment, the... of this part. (Approved by the Office of Management and Budget under control number 3220-0173)...
The Effects of Progressive Taxation on Labor Supply when Hours and Wages Are Jointly Determined
ERIC Educational Resources Information Center
Aaronson, Daniel; French, Eric
2009-01-01
This paper extends a standard intertemporal labor supply model to account for progressive taxation as well as the joint determination of hourly wages and hours worked. We show that these two factors can have implications for both estimating labor supply elasticities as well as for using these elasticities in tax analysis. Failure to account for…
26 CFR 1.83-7 - Taxation of nonqualified stock options.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., 2003. For transactions prior to that date, see § 1.83-7 as published in 26 CFR part 1 (revised as of... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Taxation of nonqualified stock options. 1.83-7... TAX (CONTINUED) INCOME TAXES (CONTINUED) Items Specifically Included in Gross Income § 1.83-7...
Paying for Equity: The Role of Taxation in Driving Canada's Educational Success
ERIC Educational Resources Information Center
Freiler, Christa
2011-01-01
Using research conducted by the federal government's own finance department, social policy groups released the report, "Paying for Canada: Perspectives on Public Finance and National Programs." It showed that deliberate government policy to reduce taxation levels for some of the most economically advantaged groups in Canada had resulted in a…
ERIC Educational Resources Information Center
Schneider, Andrea
2010-01-01
Redistributive taxation and education subsidies are common policies intended to foster education attendance of poor children. However, this paper shows that in an intergenerational framework, these policies can raise social mobility only for some investment situations but not in general. I also study the impact of both policies on the aggregate…
26 CFR 1.457-7 - Taxation of Distributions Under Eligible Plans.
Code of Federal Regulations, 2014 CFR
2014-04-01
.... 1.457-7 Section 1.457-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Included § 1.457-7 Taxation of Distributions Under Eligible Plans. (a) General rules for when amounts are.... For this purpose, the rules of section 402(c)(2) through (7) and (9) apply. Any...
26 CFR 1.457-7 - Taxation of Distributions Under Eligible Plans.
Code of Federal Regulations, 2013 CFR
2013-04-01
.... 1.457-7 Section 1.457-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Included § 1.457-7 Taxation of Distributions Under Eligible Plans. (a) General rules for when amounts are.... For this purpose, the rules of section 402(c)(2) through (7) and (9) apply. Any...
26 CFR 1.457-7 - Taxation of Distributions Under Eligible Plans.
Code of Federal Regulations, 2011 CFR
2011-04-01
.... 1.457-7 Section 1.457-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Included § 1.457-7 Taxation of Distributions Under Eligible Plans. (a) General rules for when amounts are.... For this purpose, the rules of section 402(c)(2) through (7) and (9) apply. Any...
26 CFR 1.457-7 - Taxation of Distributions Under Eligible Plans.
Code of Federal Regulations, 2012 CFR
2012-04-01
.... 1.457-7 Section 1.457-7 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY... Included § 1.457-7 Taxation of Distributions Under Eligible Plans. (a) General rules for when amounts are.... For this purpose, the rules of section 402(c)(2) through (7) and (9) apply. Any...
NASA Astrophysics Data System (ADS)
Geiyer, Daniel; Kauffman, Jeffrey L.
2016-04-01
Research in broadband nonlinear piezoelectric energy harvesting has gained traction in recent years as resonant, linear harvesters do not operate optimally in dynamic environments. By placing a linear harvester in a symmetric magnetic field, a nonlinear restoring force allows the system to realize motion across two potential wells. Different levels of excitation enable the system to oscillate solely in one potential well, periodically across both potential wells, or aperiodically across both potential wells. Periodic interwell motion is considered desirable for nonlinear energy harvesting systems, however, coexistent attractors inhibit uniqueness of such a solution. The authors have previously shown that chaotic, aperiodic motion between potential wells can be optimized for improved energy harvesting. The technique applied a chaotic controller to stabilize a large amplitude periodic orbit within the chaotic attractor. This work considers the basins of attraction of the two concurrent attractors and applies an intermittent control law in which the system is perturbed from a chaotic, aperiodic interwell response into the desirable large amplitude, periodic, interwell response.
Optimal Configuration of Large Arrays of Floating Bodies for Ocean Wave Energy Extraction
NASA Astrophysics Data System (ADS)
Tokic, Grgur; Yue, Dick K. P.
2015-11-01
We study the performance of large (O (100)) wave energy converter (WEC) arrays that are used for ocean energy harvesting. We developed a fast computational algorithm based on the multiple scattering framework that is capable of handling large arrays of different configurations (general finite-size arrays, periodic arrays, periodic arrays of subarrays); for axisymmetric bodies the algorithm imposes no constraints on the body-size-to-wavelength ratio or on the inter-body spacings. Using this fast algorithm, we optimize the spatial configurations of arrays of different types and with increasing number of bodies (up to 400), with the goal of maximizing energy extraction. The results show that employing non-uniform spacings between the bodies in ordered and non-ordered arrays can increase the array gain several times. This holds for body resonant and near-resonant frequencies, as well as for the full spectrum cases. The optimal configurations are analyzed from a physical standpoint and compared to other structured arrays in physics. These results give a guideline on the possible future design of WEC arrays.
NASA Astrophysics Data System (ADS)
Toghi Eshghi, Amin; Lee, Soobum; Lee, Hanmin; Kim, Young-Cheol
2016-04-01
In this paper, we perform design parameter study and design optimization for a piezoelectric energy harvester considering vehicle speed variation. Initially, a FEM model using ANSYS is developed to appraise the performance of a piezoelectric harvester in a rotating tire. The energy harvester proposed here uses the vertical deformation at contact patch area from the car weight and centrifugal acceleration. This harvester is composed of a beam which is clamped at both ends and a piezoelectric material is attached on the top of that. The piezoelectric material possesses the 31 mode of transduction in which the direction of applied field is perpendicular to that of the electric field. To optimize the harvester performance, we would change the geometrical parameters of the harvester to obtain the maximum power. One of the main challenges in the design process is obtaining the required power while considering the constraints for harvester weight and volume. These two concerns are addressed in this paper. Since the final goal of this study is the development of an energy harvester with a wireless sensor system installed in a real car, the real time data for varied velocity of a vehicle are taken into account for power measurements. This study concludes that the proposed design is applicable to wireless tire sensor systems.
Optimal waste-to-energy strategy assisted by GIS For sustainable solid waste management
NASA Astrophysics Data System (ADS)
Tan, S. T.; Hashim, H.
2014-02-01
Municipal solid waste (MSW) management has become more complex and costly with the rapid socio-economic development and increased volume of waste. Planning a sustainable regional waste management strategy is a critical step for the decision maker. There is a great potential for MSW to be used for the generation of renewable energy through waste incineration or landfilling with gas capture system. However, due to high processing cost and cost of resource transportation and distribution throughout the waste collection station and power plant, MSW is mostly disposed in the landfill. This paper presents an optimization model incorporated with GIS data inputs for MSW management. The model can design the multi-period waste-to-energy (WTE) strategy to illustrate the economic potential and tradeoffs for MSW management under different scenarios. The model is capable of predicting the optimal generation, capacity, type of WTE conversion technology and location for the operation and construction of new WTE power plants to satisfy the increased energy demand by 2025 in the most profitable way. Iskandar Malaysia region was chosen as the model city for this study.
Finding a way to optimize drilling depths in clastic aquifers for geothermal energy
NASA Astrophysics Data System (ADS)
van Putten, M.; van Wees, J. D. A. M.; Pluymaekers, M. P. D.; Kramers, L.
2012-04-01
Clastic aquifers generally are marked by decreasing porosity and associated permeability with depth. Uncertainties in porosity of a few percentages can result in an order of magnitude change in permeability. Further, temperature increases with depth and is marked by an uncertainty of about 10-20%. Monte Carlo performance calculations, adopting variable temperature and porosity distributions, along with other natural uncertainties and engineering options for drilling, show that performance in doublet power and levelized costs of energy (LCOE in EUR/GJ) is most sensitive to changes in the temperature gradient and the porosity. As the temperature increases with depth while the porosity decreases with depth, these relationships show a trade-off in performance, such that a theoretical optimal depth can be found for a specific temperature gradient and porosity-depth curve, and associated porosity-permeability relationship. The optimal drilling depth is at the depth level where the LCOE are minimal. In mature oil and gas basin areas, such as the Netherlands, it is possible to obtain relationships of porosity and underlying permeability as a function of depth. Therefore, the applicability for establishing and using an optimal depth has been tested for a clastic aquifer in the Rotliegend stratigraphic group in the Netherlands. This aquifer has high geothermal potential and is subject to many exploration activities. Temperature gradient and porosity-depth trends (and underlying uncertainties) for this aquifer have been adopted from the national geothermal information system ThermoGIS (www.thermogis.nl). For the performance calculation of doublet power and LCOE an in-house techno-economical performance assessment (TEPA) tool called DoubletCalc has been used. The results show that optimal depth corresponds to a pronounced and sharp minimum in LCOE. Its depth depends strongly on the actual porosity-depth relationship and ranges between 1.5 and 3 km. Remarkably, variations in
Optimal control of energy extraction in LES of large wind farms
NASA Astrophysics Data System (ADS)
Meyers, Johan; Goit, Jay; Munters, Wim
2014-11-01
We investigate the use of optimal control combined with Large-Eddy Simulations (LES) of wind-farm boundary layer interaction for the increase of total energy extraction in very large ``infinite'' wind farms and in finite farms. We consider the individual wind turbines as flow actuators, whose energy extraction can be dynamically regulated in time so as to optimally influence the turbulent flow field, maximizing the wind farm power. For the simulation of wind-farm boundary layers we use large-eddy simulations in combination with an actuator-disk representation of wind turbines. Simulations are performed in our in-house pseudo-spectral code SP-Wind. For the optimal control study, we consider the dynamic control of turbine-thrust coefficients in the actuator-disk model. They represent the effect of turbine blades that can actively pitch in time, changing the lift- and drag coefficients of the turbine blades. In a first infinite wind-farm case, we find that farm power is increases by approximately 16% over one hour of operation. This comes at the cost of a deceleration of the outer layer of the boundary layer. A detailed analysis of energy balances is presented, and a comparison is made between infinite and finite farm cases, for which boundary layer entrainment plays an import role. The authors acknowledge support from the European Research Council (FP7-Ideas, Grant No. 306471). Simulations were performed on the computing infrastructure of the VSC Flemish Supercomputer Center, funded by the Hercules Foundation and the Flemish Govern.
Validating the method of pressure sensing to optimize flapping foil energy extraction
NASA Astrophysics Data System (ADS)
Persichetti, Amanda J.
Renewable energy resources are in high demand due to a world-wide desire for cleaner energy production. Flapping foil tidal driven systems have begun being tested and implemented at prototype scales. These prototype systems use limited control to maximize energy production. This thesis uses biological inspiration from the sensory system in fish to enhance the efficiency of these energy harnessing systems with the use of surface mounted pressure sensing. Eight pressure sensors were found to be a good balance for quantity with respect to cost and accuracy. Optimal locations around the foil were determined from application of a Random Search algorithm and a fluid moment approximation. A 2-D numerical code was created to simulate a NACA0015 flapping foil in uniform potential flow. A wide parameter space of sinusoidal heave and pitch motions was run and a database of force, pressure, and efficiency values along with flow visualization was built. An efficiency of 0.43 was reached for the trajectory of motion with a pitch amplitude of 90 degrees, heave amplitude of 1.25 and a Strouhal number of 0.5. A control platform dependent on pressure measurements at the eight sensor locations was created in the 2-D numerical code. By implementing basic control, motion trajectories converge to the optimal motion based on pressure comparisons around the foil to pressure traces from the motion with highest efficiency. In addition, a laboratory for experimental testing and validation was set-up. The motion control system was connected and tested for a tow tank set-up. Motion programs were written for the same parameter space modeled in this thesis. Through numerical modeling, pressure sensing was found to be an effective method to enhancing the efficiency of a flapping foil energy extraction system.
Water-Energy Nexus: Examining The Crucial Connection Through Simulation Based Optimization
NASA Astrophysics Data System (ADS)
Erfani, T.; Tan, C. C.
2014-12-01
With a growing urbanisation and the emergence of climate change, the world is facing a more water constrained future. This phenomenon will have direct impacts on the resilience and performance of energy sector as water is playing a key role in electricity generation processes. As energy is becoming a thirstier resource and the pressure on finite water sources is increasing, modelling and analysing this closely interlinked and interdependent loop, called 'water-energy nexus' is becoming an important cross-disciplinary challenge. Conflict often arises in transboundary river where several countries share the same source of water to be used in productive sectors for economic growth. From the perspective of the upstream users, it would be ideal to store the water for hydropower generation and protect the city against drought whereas the downstream users need the supply of water for growth. This research use the case study on the transboundary Blue Nile River basin located in the Middle East where the Ethiopian government decided to invest on building a new dam to store the water and generate hydropower. This leads to an opposition by downstream users as they believe that the introduction of the dam would reduce the amount of water available downstream. This calls for a compromise management where the reservoir operating rules need to be derived considering the interdependencies between the resources available and the requirements proposed by all users. For this, we link multiobjective optimization algorithm to water-energy use simulation model to achieve effective management of the transboundary reservoir operating strategies. The objective functions aim to attain social and economic welfare by minimizing the deficit of water supply and maximizing the hydropower generation. The study helps to improve the policies by understanding the value of water and energy in their alternative uses. The results show how different optimal reservoir release rules generate different
NASA Astrophysics Data System (ADS)
Arai, Yuuki; Yamashita, Tomohisa; Hasegawa, Hitoshi; Matsuoka, Taro; Kaimori, Hiroyuki; Ishihara, Terumasa
Levitation and guidance force is electromagnetic generated between a superconducting coil and zero field cooled bulk superconductors used in our flywheel energy storage system (FESS). Because the magnetic field depends on the configuration of the coil and the bulks, the eccentricity and the vibration of a rotor cause fluctuation in the magnetic field which induces eddy current and consequent Joule heat on electric conductors such as cooling plates. Heat generation in the cryogenic region critically reduces the efficiency of the FESS. In this paper, we will report the result of the electromagnetic analysis of the SMB and propose an optimal divided cooling plate for reducing the eddy current and Joule heat.
Optimal Position Estimation for the Automatic Alignment of a High Energy Laser
Candy, J V; Mcclay, W A; Awwal, A S; Ferguson, S W
2004-07-20
The alignment of high energy laser beams for potential fusion experiments demand high precision and accuracy by the underlying positioning algorithms whether it be for actuator control or monitoring the beam line for potential anomalies. This paper discusses the feasibility of employing on-line optimal position estimators in the form of model-based processors to achieve the desired results. Here we discuss the modeling, development, implementation and processing of model-based processors applied to both simulated and actual beam line data.
Healthy food subsidies and unhealthy food taxation: A systematic review of the evidence.
Niebylski, Mark L; Redburn, Kimbree A; Duhaney, Tara; Campbell, Norm R
2015-06-01
The Global Burden of Disease Study and related studies report unhealthy diet is the leading risk for death and disability globally. Given the evidence associating diet and non-communicable diseases (NCDs), international and national health bodies including the World Health Organization and United Nations have called for population health interventions to improve diet as a means to target NCDs. One of the proposed interventions is to ensure healthy foods/beverages are more accessible to purchasers and unhealthy ones less accessible via fiscal policy, namely taxation and subsidies. The objective of this systematic review was to evaluate the evidence base to assess the effect of healthy food/beverage subsidies and unhealthy food/beverage taxation. A comprehensive review was conducted by searching PubMed, Medline, and Google Scholar for peer-reviewed publications and seventy-eight studies were identified for inclusion in this review. This review was performed in keeping with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance. Although moderate in quality, there was consistent evidence that taxation and subsidy intervention influenced dietary behaviors. The quality, level and strength of evidence along with identified gaps in research support the need for further policies and ongoing evaluation of population-wide food/beverage subsidies and taxation. To maximize success and effect, this review suggests that food taxes and subsidies should be a minimum of 10 to 15% and preferably used in tandem. Implementation of population-wide polices for taxation and subsides with ongoing evaluation of intended and unintended effects are supported by this review. PMID:25933484
Towards a hybrid energy efficient multi-tree-based optimized routing protocol for wireless networks.
Mitton, Nathalie; Razafindralambo, Tahiry; Simplot-Ryl, David; Stojmenovic, Ivan
2012-01-01
This paper considers the problem of designing power efficient routing with guaranteed delivery for sensor networks with unknown geographic locations. We propose HECTOR, a hybrid energy efficient tree-based optimized routing protocol, based on two sets of virtual coordinates. One set is based on rooted tree coordinates, and the other is based on hop distances toward several landmarks. In HECTOR, the node currently holding the packet forwards it to its neighbor that optimizes ratio of power cost over distance progress with landmark coordinates, among nodes that reduce landmark coordinates and do not increase distance in tree coordinates. If such a node does not exist, then forwarding is made to the neighbor that reduces tree-based distance only and optimizes power cost over tree distance progress ratio. We theoretically prove the packet delivery and propose an extension based on the use of multiple trees. Our simulations show the superiority of our algorithm over existing alternatives while guaranteeing delivery, and only up to 30% additional power compared to centralized shortest weighted path algorithm. PMID:23443398
An, Chansik; Chun, Yong-Min; Kim, Sungjun; Lee, Young Han; Yun, Min Jeong; Suh, Jin-Suck
2014-01-01
Objective To optimize the dose of contrast agent and the level of energy for dual-energy computed tomography (DECT) arthrography of the shoulder joint and to evaluate the benefits of the optimized imaging protocol. Materials and Methods Dual-energy scans with monochromatic spectral imaging mode and conventional single energy scans were performed on a shoulder phantom with 10 concentrations from 0 to 210 mg/mL of iodinated contrast medium at intervals of 15 or 30 mg/mL. Image noise, tissue contrast, and beam hardening artifacts were assessed to determine the optimum dose of contrast agent and the level of monochromatic energy for DECT shoulder arthrography in terms of the lowest image noise and the least beam hardening artifacts while good tissue contrast was maintained. Material decomposition (MD) imaging for bone-iodine differentiation was qualitatively assessed. The optimized protocol was applied and evaluated in 23 patients. Results The optimal contrast dose and energy level were determined by the phantom study at 60 mg/mL and 72 keV, respectively. This optimized protocol for human study reduced the image noise and the beam-hardening artifacts by 35.9% and 44.5%, respectively. Bone-iodine differentiation by MD imaging was not affected by the iodine concentration or level of energy. Conclusion Dual-energy scan with monochromatic spectral imaging mode results in reduced image noise and beam hardening artifacts. PMID:25469086
A multi-period optimization model for energy planning with CO(2) emission consideration.
Mirzaesmaeeli, H; Elkamel, A; Douglas, P L; Croiset, E; Gupta, M
2010-05-01
A novel deterministic multi-period mixed-integer linear programming (MILP) model for the power generation planning of electric systems is described and evaluated in this paper. The model is developed with the objective of determining the optimal mix of energy supply sources and pollutant mitigation options that meet a specified electricity demand and CO(2) emission targets at minimum cost. Several time-dependent parameters are included in the model formulation; they include forecasted energy demand, fuel price variability, construction lead time, conservation initiatives, and increase in fixed operational and maintenance costs over time. The developed model is applied to two case studies. The objective of the case studies is to examine the economical, structural, and environmental effects that would result if the electricity sector was required to reduce its CO(2) emissions to a specified limit. PMID:20149519
Nonlocal energy-optimized kernel: Recovering second-order exchange in the homogeneous electron gas
NASA Astrophysics Data System (ADS)
Bates, Jefferson E.; Laricchia, Savio; Ruzsinszky, Adrienn
2016-01-01
In order to remedy some of the shortcomings of the random phase approximation (RPA) within adiabatic connection fluctuation-dissipation (ACFD) density functional theory, we introduce a short-ranged, exchange-like kernel that is one-electron self-correlation free and exact for two-electron systems in the high-density limit. By tuning a free parameter in our model to recover an exact limit of the homogeneous electron gas correlation energy, we obtain a nonlocal, energy-optimized kernel that reduces the errors of RPA for both homogeneous and inhomogeneous solids. Using wave-vector symmetrization for the kernel, we also implement RPA renormalized perturbation theory for extended systems, and demonstrate its capability to describe the dominant correlation effects with a low-order expansion in both metallic and nonmetallic systems. The comparison of ACFD structural properties with experiment is also shown to be limited by the choice of norm-conserving pseudopotential.
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.
Optimization of Gear Ratio in the Tidal Current Generation System based on Generated Energy
NASA Astrophysics Data System (ADS)
Naoi, Kazuhisa; Shiono, Mitsuhiro; Suzuki, Katsuyuki
It is possible to predict generating power of the tidal current generation, because of the tidal current's periodicity. Tidal current generation is more advantageous than other renewable energy sources, when the tidal current generation system is connected to the power system and operated. In this paper, we propose a method used to optimize the gear ratio and generator capacity, that is fundamental design items in the tidal current generation system which is composed of Darrieus type water turbine and squirrel-cage induction generator coupled with gear. The proposed method is applied to the tidal current generation system including the most large-sized turbine that we have developed and studied. This paper shows optimum gear ratio and generator capacity that make generated energy maximum, and verify effectiveness of the proposed method. The paper also proposes a method of selecting maximum generating current velocity in order to reduce the generator capacity, from the viewpoint of economics.
Long-term energy capture and the effects of optimizing wind turbine operating strategies
NASA Technical Reports Server (NTRS)
Miller, A. H.; Formica, W. J.
1982-01-01
Methods of increasing energy capture without affecting the turbine design were investigated. The emphasis was on optimizing the wind turbine operating strategy. The operating strategy embodies the startup and shutdown algorithm as well as the algorithm for determining when to yaw (rotate) the axis of the turbine more directly into the wind. Using data collected at a number of sites, the time-dependent simulation of a MOD-2 wind turbine using various, site-dependent operating strategies provided evidence that site-specific fine tuning can produce significant increases in long-term energy capture as well as reduce the number of start-stop cycles and yawing maneuvers, which may result in reduced fatigue and subsequent maintenance.
Optimize out-of-core thermionic energy conversion for nuclear electric propulsion
NASA Technical Reports Server (NTRS)
Morris, J. F.
1978-01-01
Thermionic energy conversion (TEC) potentialities for nuclear electric propulsion (NEP) are examined. Considering current designs, their limitations, and risks raises critical questions about the use of TEC for NEP. Apparently a reactor cooled by hotter-than-1675 K heat pipes has good potentialities. TEC with higher temperatures and greater power densities than the currently proposed 1650 K, 5-to-6 W/sq cm version offers substantial gains. Other approaches to high-temperature electric isolation appear also promising. A high-power-density, high-temperature TEC for NEP appears, therefore, attainable. It is recommended to optimize out-of-core thermionic energy conversion for nuclear electric propulsion. Although current TEC designs for NEP seem unnecessary compared with Brayton versions, large gains are apparently possible with increased temperatures and greater power densities.
NASA Astrophysics Data System (ADS)
Tsampas, P.; Roditis, G.; Papadimitriou, V.; Chatzakos, P.; Gan, Tat-Hean
2013-05-01
Increasing demand in mobile, autonomous devices has made energy harvesting a particular point of interest. Systems that can be powered up by a few hundreds of microwatts could feature their own energy extraction module. Energy can be harvested from the environment close to the device. Particularly, the ambient mechanical vibrations conversion via piezoelectric transducers is one of the most investigated fields for energy harvesting. A technique for optimized energy harvesting using piezoelectric actuators called "Synchronized Switching Harvesting" is explored. Comparing to a typical full bridge rectifier, the proposed harvesting technique can highly improve harvesting efficiency, even in a significantly extended frequency window around the piezoelectric actuator's resonance. In this paper, the concept of design, theoretical analysis, modeling, implementation and experimental results using CEDRAT's APA 400M-MD piezoelectric actuator are presented in detail. Moreover, we suggest design guidelines for optimum selection of the storage unit in direct relation to the characteristics of the random vibrations. From a practical aspect, the harvesting unit is based on dedicated electronics that continuously sense the charge level of the actuator's piezoelectric element. When the charge is sensed, to come to a maximum, it is directed to speedily flow into a storage unit. Special care is taken so that electronics operate at low voltages consuming a very small amount of the energy stored. The final prototype developed includes the harvesting circuit implemented with miniaturized, low cost and low consumption electronics and a storage unit consisting of a super capacitors array, forming a truly self-powered system drawing energy from ambient random vibrations of a wide range of characteristics.
Optimal sizing of heating systems that store and use thermal energy
NASA Astrophysics Data System (ADS)
Hersh, H. N.
1981-06-01
An analysis of the factors that enter into the sizing of thermal energy storage (TES) space heating systems is given. These TES systems, having to fulfill the same thermal comfort functions as conventional space heating systems, have different operating characteristics and more severe constraints, and therefore require different and more critical sizing procedures. Thermal energy storage heating systems offer social and private benefits, and the achievement of these benefits depends in large part on proper sizing. Proper sizing is a probabilistic rather than a deterministic procedure, and is utility-specific as well. Analysis of experimental data obtained in field studies of TEST in New England provided information on the accuracy of equipment-sizing procedures used by vendors and on the consequences of undersizing and oversizing. Based on simulation studies and other techniques, additional useful sizing information was developed. The information implies the need for an upward adjustment of the sizing factor if the sizing is to be optimal for US climatological conditions and living habits. A summary and a general theoretical analysis of the information presented in this report are then combined to provide guidelines for optimally sizing TES systems.
Lacommare, Kristina S H; Stadler, Michael; Aki, Hirohisa; Firestone, Ryan; Lai, Judy; Marnay, Chris; Siddiqui, Afzal
2008-05-15
The addition of storage technologies such as flow batteries, conventional batteries, and heat storage can improve the economic as well as environmental attractiveness of on-site generation (e.g., PV, fuel cells, reciprocating engines or microturbines operating with or without CHP) and contribute to enhanced demand response. In order to examine the impact of storage technologies on demand response and carbon emissions, a microgrid's distributed energy resources (DER) adoption problem is formulated as a mixed-integer linear program that has the minimization of annual energy costs as its objective function. By implementing this approach in the General Algebraic Modeling System (GAMS), the problem is solved for a given test year at representative customer sites, such as schools and nursing homes, to obtain not only the level of technology investment, but also the optimal hourly operating schedules. This paper focuses on analysis of storage technologies in DER optimization on a building level, with example applications for commercial buildings. Preliminary analysis indicates that storage technologies respond effectively to time-varying electricity prices, i.e., by charging batteries during periods of low electricity prices and discharging them during peak hours. The results also indicate that storage technologies significantly alter the residual load profile, which can contribute to lower carbon emissions depending on the test site, its load profile, and its adopted DER technologies.
Optimization of adsorption processes for climate control and thermal energy storage
Narayanan, S; Yang, S; Kim, H; Wang, EN
2014-10-01
Adsorption based heat-pumps have received significant interest owing to their promise of higher efficiencies and energy savings when coupled with waste heat and solar energy compared to conventional heating and cooling systems. While adsorption systems have been widely studied through computational analysis and experiments, general design guidelines to enhance their overall performance have not been proposed. In this work, we identified conditions suitable for the maximum utilization of the adsorbent to enhance the performance of both intermittent as well as continuously operating adsorption systems. A detailed computational model was developed based on a general framework governing adsorption dynamics in a single adsorption layer and pellet. We then validated the computational analysis using experiments with a model system of zeolite 13X-water for different operating conditions. A dimensional analysis was subsequently carried out to optimize adsorption performance for any desired operating condition, which is determined by the choice of adsorbent-vapor pair, adsorption duration, operational pressure, intercrystalline porosity, adsorbent crystal size, and intracrystalline vapor diffusivity. The scaling analysis identifies the critical dimensionless parameters and provides a simple guideline to determine the most suitable geometry for the adsorbent particles. Based on this selection criterion, the computational model was used to demonstrate maximum utilization of the adsorbent for any given operational condition. By considering a wide range of parametric variations for performance optimization, these results offer important insights for designing adsorption beds for heating and cooling systems. (C) 2014 Elsevier Ltd. All rights reserved.