Energy Design Advice Scheme (EDAS): operations and achievements 1992-1998

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-09-01

The Energy Design Advice Scheme (EDAS) was launched in 1992 under the DTI's Passive Solar Programme to help improve the energy performance of the UK's building stock. It aimed to do this through direct advice and guidance on passive solar design and energy efficient technologies and processes given to the designers of real building projects. Furthermore, the scheme aimed to raise the awareness and take-up of definitive guidance produced under government programmes such as the Passive Solar programme and the Energy Efficiency Best Practice programme. A target energy saving worth Pound 19.3m was set to be achieved by the end of the scheme. This energy saving is equivalent to a reduction in carbon dioxide emission of 220,000 tonnes per year. (author)

An Energy Efficient Cooperative Hierarchical MIMO Clustering Scheme for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Sungyoung Lee

2011-12-01

Full Text Available In this work, we present an energy efficient hierarchical cooperative clustering scheme for wireless sensor networks. Communication cost is a crucial factor in depleting the energy of sensor nodes. In the proposed scheme, nodes cooperate to form clusters at each level of network hierarchy ensuring maximal coverage and minimal energy expenditure with relatively uniform distribution of load within the network. Performance is enhanced by cooperative multiple-input multiple-output (MIMO communication ensuring energy efficiency for WSN deployments over large geographical areas. We test our scheme using TOSSIM and compare the proposed scheme with cooperative multiple-input multiple-output (CMIMO clustering scheme and traditional multihop Single-Input-Single-Output (SISO routing approach. Performance is evaluated on the basis of number of clusters, number of hops, energy consumption and network lifetime. Experimental results show significant energy conservation and increase in network lifetime as compared to existing schemes.

An entropy-variables-based formulation of residual distribution schemes for non-equilibrium flows

Science.gov (United States)

Garicano-Mena, Jesús; Lani, Andrea; Degrez, Gérard

2018-06-01

In this paper we present an extension of Residual Distribution techniques for the simulation of compressible flows in non-equilibrium conditions. The latter are modeled by means of a state-of-the-art multi-species and two-temperature model. An entropy-based variable transformation that symmetrizes the projected advective Jacobian for such a thermophysical model is introduced. Moreover, the transformed advection Jacobian matrix presents a block diagonal structure, with mass-species and electronic-vibrational energy being completely decoupled from the momentum and total energy sub-system. The advantageous structure of the transformed advective Jacobian can be exploited by contour-integration-based Residual Distribution techniques: established schemes that operate on dense matrices can be substituted by the same scheme operating on the momentum-energy subsystem matrix and repeated application of scalar scheme to the mass-species and electronic-vibrational energy terms. Finally, the performance gain of the symmetrizing-variables formulation is quantified on a selection of representative testcases, ranging from subsonic to hypersonic, in inviscid or viscous conditions.

An Energy-Efficient Scheme for Multirelay Cooperative Networks with Energy Harvesting

Directory of Open Access Journals (Sweden)

Dingcheng Yang

2016-01-01

Full Text Available This study investigates an energy-efficient scheme in multirelay cooperative networks with energy harvesting where multiple sessions need to communicate with each other via the relay node. A two-step optimal method is proposed which maximizes the system energy efficiency, while taking into account the receiver circuit energy consumption. Firstly, the optimal power allocation for relay nodes is determined to maximize the system throughput; this is based on directional water-filling algorithm. Secondly, using quantum particle swarm optimization (QPSO, a joint relay node selection and session grouping optimization is proposed. With this algorithm, sessions can be classified into multiple groups that are assisted by the specific relay node with the maximum energy efficiency. This approach leads to a better global optimization in searching ability and efficiency. Simulation results show that the proposed scheme can improve the energy efficiency effectively compared with direct transmission and opportunistic relay-selected cooperative transmission.

Harvested Energy Prediction Schemes for Wireless Sensor Networks: Performance Evaluation and Enhancements

Directory of Open Access Journals (Sweden)

Muhammad

2017-01-01

Full Text Available We review harvested energy prediction schemes to be used in wireless sensor networks and explore the relative merits of landmark solutions. We propose enhancements to the well-known Profile-Energy (Pro-Energy model, the so-called Improved Profile-Energy (IPro-Energy, and compare its performance with Accurate Solar Irradiance Prediction Model (ASIM, Pro-Energy, and Weather Conditioned Moving Average (WCMA. The performance metrics considered are the prediction accuracy and the execution time which measure the implementation complexity. In addition, the effectiveness of the considered models, when integrated in an energy management scheme, is also investigated in terms of the achieved throughput and the energy consumption. Both solar irradiance and wind power datasets are used for the evaluation study. Our results indicate that the proposed IPro-Energy scheme outperforms the other candidate models in terms of the prediction accuracy achieved by up to 78% for short term predictions and 50% for medium term prediction horizons. For long term predictions, its prediction accuracy is comparable to the Pro-Energy model but outperforms the other models by up to 64%. In addition, the IPro scheme is able to achieve the highest throughput when integrated in the developed energy management scheme. Finally, the ASIM scheme reports the smallest implementation complexity.

Energy Design Advice Scheme (EDAS): operations and achievements 1992-1998

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-09-01

The Energy Design Advice Scheme (EDAS) was launched in 1992 under the DTI's Passive Solar Programme to help improve the energy performance of the UK's building stock. It aimed to do this through direct advice and guidance on passive solar design and energy efficient technologies and processes given to the designers of real building projects. Furthermore, the scheme aimed to raise the awareness and take-up of definitive guidance produced under government programmes such as the Passive Solar programme and the Energy Efficiency Best Practice programme. A target energy saving worth Pound 19.3m was set to be achieved by the end of the scheme. This energy saving is equivalent to a reduction in carbon dioxide emission of 220,000 tonnes per year. (author)

Automated flaw detection scheme for cast austenitic stainless steel weld specimens using Hilbert-Huang transform of ultrasonic phased array data

International Nuclear Information System (INIS)

Khan, Tariq; Majumdar, Shantanu; Udpa, Lalita; Ramuhalli, Pradeep; Crawford, Susan; Diaz, Aaron; Anderson, Michael T.

2012-01-01

The objective of this work is to develop processing algorithms to detect and localize flaws using ultrasonic phased-array data. Data was collected on cast austenitic stainless stell (CASS) weld specimens onloan from the U.S. nuclear power industry' Pressurized Walter Reactor Owners Group (PWROG) traveling specimen set. Each specimen consists of a centrifugally cast stainless stell (CCSS) pipe section welded to a statically cst(SCSS) or wrought (WRSS) section. The paper presents a novel automated flaw detection and localization scheme using low frequency ultrasonic phased array inspection singals from the weld and heat affected zone of the based materials. The major steps of the overall scheme are preprocessing and region of interest (ROI) detection followed by the Hilbert-Huang transform (HHT) of A-scans in the detected ROIs. HHT offers time-frequency-energy distribution for each ROI. The Accumulation of energy in a particular frequency band is used as a classification feature for the particular ROI

Energy sales targets: An alternative to White Certificate schemes

International Nuclear Information System (INIS)

Passey, Robert; MacGill, Iain

2009-01-01

White Certificate schemes are currently being implemented or proposed in a growing number of jurisdictions as a means to drive greater energy efficiency uptake. After briefly discussing some of the strengths and weaknesses of such schemes, this paper outlines a proposed alternative approach-the use of Energy Sales Targets. This approach essentially involves the imposition of a cap on the greenhouse gas (GHG) emissions associated with annual energy sales and, in its simplest version, requires no tradeable certificates or permits. The proposed approach creates a clear measurable link between how compliance is enforced (the retailers' targets) and the desired outcomes of the scheme (measurable reductions in GHG emissions). This drives physical additionality of the scheme, including negation of any rebound effect within the covered sectors. It also avoids the need to define the activities eligible to create certificates, and likewise, no deeming, auditing, monitoring or verification would be required by government beyond ensuring retailer compliance-significantly reducing administration costs. There does not appear to be a clear precedent for this type of scheme anywhere in the world, and so this paper should be seen as a preliminary scoping of options that are deserving of more in-depth assessment.

Unconditionally energy stable numerical schemes for phase-field vesicle membrane model

Science.gov (United States)

Guillén-González, F.; Tierra, G.

2018-02-01

Numerical schemes to simulate the deformation of vesicles membranes via minimizing the bending energy have been widely studied in recent times due to its connection with many biological motivated problems. In this work we propose a new unconditionally energy stable numerical scheme for a vesicle membrane model that satisfies exactly the conservation of volume constraint and penalizes the surface area constraint. Moreover, we extend these ideas to present an unconditionally energy stable splitting scheme decoupling the interaction of the vesicle with a surrounding fluid. Finally, the well behavior of the proposed schemes are illustrated through several computational experiments.

Scheme of energy collective services; Schema de services collectifs de l'energie

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

The scheme of collective energy services aims at facilitating and valorizing the contribution of the national organizations to the national energy plan and to the durable development of the country. The scheme comprises three main goals: defining the exploitation goals of local renewable energy resources and the goals of rational energy uses which can contribute to the national energy independence, to the security of supplies and to the abatement of the greenhouse effect; evaluating the foreseeable energy needs of regions and their energy production potentiality, their energy saving possibilities and their energy transportation needs; and finally, determining the conditions in which the government and the national organizations will be able to favor the energy saving actions and the production and use of renewable energies taking into account their impact on employment and their long-term financial consequences. This document is organized in five parts: 1 - status, stakes and perspectives: energy demand perspectives at the 2010-2020 vista, potentialities of energy saving and renewable energy sources development, implication of the international commitment of France in the fight against greenhouse effect; 2 - action means for new measures: buildings and accommodations, transportation sector, industry sector, mastery of electricity demand, development of renewable energy sources, decentralized energy production, energy storage, transport and distribution, economic tools and public means of sustain; 3 - follow up of the scheme of energy collective services; 4 - analysis of regional contributions; 5 - appendixes and maps. (J.S.)

Dynamic droop scheme considering effect of intermittent renewable energy source

DEFF Research Database (Denmark)

Wang, Yanbo; Chen, Zhe; Deng, Fujin

2016-01-01

This paper presents a dynamic droop control scheme for islanded microgrids dominated by intermittent renewable energy sources, which is able to perform desirable power sharing in the presence of renewable energy source fluctuation. First, allowable maximum power points of wind generator and PV...... flexibility and effectiveness in the presence of the renewable energy sources fluctuation....... controller of each DG unit is activated through local logic variable inferred by wind speed and solar insolation information. Simulation results are given for validating the droop control scheme. The proposed dynamic droop scheme preserves the advantage of conventional droop control method, and provides...

An Energy-aware Routing Scheme in Delay Tolerant Mobile Sensor Networking

Directory of Open Access Journals (Sweden)

Zhe Chen

2014-08-01

Full Text Available In Delay Tolerant Mobile Sensor Networking (DTMSN, mobile sensor nodes are usually limited to their energy capacity, one important concern in routing design of DTMSN is energy consumption. This paper presents a number of variations of the Epidemic Routing Protocol (ERP to extend the DTMSN lifetime. It introduces the analytical model for ERP, after introducing the concepts behind the Target Delivery Probability and Minimum Delivery Probability, it defines the network lifetime. In this paper, it firstly studies many variations of the Epidemic Routing Protocol to extend the lifetime of the DTMSN. Secondly, based on the Epidemic Routing Protocol, three schemes are introduced. Those schemes rely on the limiting the times of message allowed for propagation (LT scheme, directly controlling the number of the copies (LC scheme, split the copies to the residual energies of the nodes (LE scheme. Finally, with the experiment and the validation of the simulation, the LE scheme can significantly maximize the lifetime of DTMSN, because it minimizes the number of copies and that shifts the generation of the copies to the nodes with larger residual energy.

Assessment of Climate Air Energy Regional Schemes in Burgundy and in Franche-Comte - Intermediate review on June 27, 2017. Burgundy Climate Air Energy Regional Scheme. Project, Scheme, Appendix to the SRCAE - Wind regional scheme of Burgundy, synthesis, opinion of the Burgundy CESER. Territorial Climate Energy Plan - Program of actions, Plenary session of the November 25, 2013. Climate Air Energy Regional Scheme - Franche-Comte SRCAE

International Nuclear Information System (INIS)

2011-09-01

A first report proposes an assessment of the various aspects addressed by the Climate Air Energy Regional Schemes (SRCAE) of Burgundy and Franche-Comte: global aspects, and aspects related to adaptation to climate change, to air quality, to land planning, to the building sector, to mobility, to good transports, to agriculture, to forest, to industry and craft, to renewable energies, and to ecological responsibility. A synthetic presentation of the Burgundy scheme is proposed, and then an extended version which contains a description of the situation, an analysis of the regional potential, and a definition of orientations for the same above-mentioned aspects. A document more particularly addresses wind energy: role of wind energy in the energy mix of the region, role of small installations, wind energy potential, challenges and constraints (heritage and landscapes, natural environment, technical constraints), identification of areas of interest for wind energy projects, qualitative objectives. Documents published by the regional economic, social and environmental Council (CESER) of Burgundy are then proposed: a contribution to the Climate Air Energy Regional Scheme, a discussion and a presentation of a program of actions for the Climate Energy Territorial Plan (a large number of sheets of presentation of actions is proposed). The last document presents the Franche-Comte regional scheme: overview of regional knowledge on climate, air quality and environmental issues, challenges and potential per activity sector (transports and development, building, agriculture, industry, renewable energy production), definition of orientations and objectives for axes of action

Electrodynamic energy harvester for electrical transformer's ...

Indian Academy of Sciences (India)

Electrical transformer; electrodynamic; energy harvester; self-powered ...... Kennedy S P and Gordner T 2013 Hot spot studies for sheet wound transformer wind- ... and Lambert F 2011 Powering low-cost utility sensors using energy harvesting.

Reconstructive schemes for variational iteration method within Yang-Laplace transform with application to fractal heat conduction problem

Directory of Open Access Journals (Sweden)

Liu Chun-Feng

2013-01-01

Full Text Available A reconstructive scheme for variational iteration method using the Yang-Laplace transform is proposed and developed with the Yang-Laplace transform. The identification of fractal Lagrange multiplier is investigated by the Yang-Laplace transform. The method is exemplified by a fractal heat conduction equation with local fractional derivative. The results developed are valid for a compact solution domain with high accuracy.

Macro-level integrated renewable energy production schemes for sustainable development

International Nuclear Information System (INIS)

Subhadra, Bobban G.

2011-01-01

The production of renewable clean energy is a prime necessity for the sustainable future existence of our planet. However, because of the resource-intensive nature, and other challenges associated with these new generation renewable energy sources, novel industrial frameworks need to be co-developed. Integrated renewable energy production schemes with foundations on resource sharing, carbon neutrality, energy-efficient design, source reduction, green processing plan, anthropogenic use of waste resources for the production green energy along with the production of raw material for allied food and chemical industries is imperative for the sustainable development of this sector especially in an emission-constrained future industrial scenario. To attain these objectives, the scope of hybrid renewable production systems and integrated renewable energy industrial ecology is briefly described. Further, the principles of Integrated Renewable Energy Park (IREP) approach, an example for macro-level energy production, and its benefits and global applications are also explored. - Research highlights: → Discusses the need for macro-level renewable energy production schemes. → Scope of hybrid and integrated industrial ecology for renewable energy production. → Integrated Renewable Energy Parks (IREPs): A macro-level energy production scheme. → Discusses the principle foundations and global applications of IREPs. → Describes the significance of IREPs in the carbon-neutral future business arena.

Renewable energy investments under different support schemes: A real options approach

DEFF Research Database (Denmark)

Boomsma, Trine Krogh; Meade, Nigel; Fleten, Stein-Erik

2012-01-01

-in tariff encourages earlier investment. Nevertheless, as investment has been undertaken, renewable energy certificate trading creates incentives for larger projects. In our baseline scenario and taking the fixed feed-in tariff as a base, the revenue required to trigger investments is 61% higher......This paper adopts a real options approach to analyze investment timing and capacity choice for renewable energy projects under different support schemes. The main purpose is to examine investment behavior under the most extensively employed support schemes, namely, feed-in tariffs and renewable...... energy certificate trading. We consider both multiple sources of uncertainty under each support scheme and uncertainty with respect to any change of support scheme, and we obtain both analytical (when possible) and numerical solutions. In a Nordic case study based on wind power, we find that the feed...

Statistical interpretation of low energy nuclear level schemes

Energy Technology Data Exchange (ETDEWEB)

Egidy, T von; Schmidt, H H; Behkami, A N

1988-01-01

Nuclear level schemes and neutron resonance spacings yield information on level densities and level spacing distributions. A total of 75 nuclear level schemes with 1761 levels and known spins and parities was investigated. The A-dependence of level density parameters is discussed. The spacing distributions of levels near the groundstate indicate transitional character between regular and chaotic properties while chaos dominates near the neutron binding energy.

Energy Efficient MAC Scheme for Wireless Sensor Networks with High-Dimensional Data Aggregate

Directory of Open Access Journals (Sweden)

Seokhoon Kim

2015-01-01

Full Text Available This paper presents a novel and sustainable medium access control (MAC scheme for wireless sensor network (WSN systems that process high-dimensional aggregated data. Based on a preamble signal and buffer threshold analysis, it maximizes the energy efficiency of the wireless sensor devices which have limited energy resources. The proposed group management MAC (GM-MAC approach not only sets the buffer threshold value of a sensor device to be reciprocal to the preamble signal but also sets a transmittable group value to each sensor device by using the preamble signal of the sink node. The primary difference between the previous and the proposed approach is that existing state-of-the-art schemes use duty cycle and sleep mode to save energy consumption of individual sensor devices, whereas the proposed scheme employs the group management MAC scheme for sensor devices to maximize the overall energy efficiency of the whole WSN systems by minimizing the energy consumption of sensor devices located near the sink node. Performance evaluations show that the proposed scheme outperforms the previous schemes in terms of active time of sensor devices, transmission delay, control overhead, and energy consumption. Therefore, the proposed scheme is suitable for sensor devices in a variety of wireless sensor networking environments with high-dimensional data aggregate.

Missing texture reconstruction method based on error reduction algorithm using Fourier transform magnitude estimation scheme.

Science.gov (United States)

Ogawa, Takahiro; Haseyama, Miki

2013-03-01

A missing texture reconstruction method based on an error reduction (ER) algorithm, including a novel estimation scheme of Fourier transform magnitudes is presented in this brief. In our method, Fourier transform magnitude is estimated for a target patch including missing areas, and the missing intensities are estimated by retrieving its phase based on the ER algorithm. Specifically, by monitoring errors converged in the ER algorithm, known patches whose Fourier transform magnitudes are similar to that of the target patch are selected from the target image. In the second approach, the Fourier transform magnitude of the target patch is estimated from those of the selected known patches and their corresponding errors. Consequently, by using the ER algorithm, we can estimate both the Fourier transform magnitudes and phases to reconstruct the missing areas.

Status Review of Renewable and Energy Efficiency Support Schemes in Europe

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-09-15

This document forms the latest update to the regular CEER Status Review of Renewable Energy and Energy Efficiency Support Schemes in Europe and builds on the previous CEER report C10-SDE-19-04a. The purpose of Status Review publications is to collect comparable data on RES support in Europe in order to provide policy-makers, regulators and industry participants with information on support schemes for electricity from renewable energy sources, by technology and type of instrument (e.g. Feed-in tariffs and Green Certificates). To collect this data, a questionnaire was circulated to CEER members in July 2012, to explore the renewable electricity support schemes currently in place in Member States across Europe.

Development of a Compensation Scheme for a Measurement Voltage Transformer Using the Hysteresis Characteristics of a Core

Directory of Open Access Journals (Sweden)

Hyewon Lee

2015-04-01

Full Text Available This paper describes the design, evaluation, and implementation of a compensation scheme for a measurement voltage transformer (VT using the hysteresis characteristics of the core. The error of a VT is caused by the primary winding voltage and secondary winding voltage. The latter depends on the secondary current, whereas the former depends on the primary current, which is an aggregate of the exciting and secondary currents. The secondary current is obtained directly from the secondary voltage and is used to obtain the voltage across the secondary winding. For the primary current, the exciting current is decomposed into two components: core-loss and magnetizing currents. The magnetizing current is obtained by the flux-magnetizing current curve instead of the hysteresis loop to minimize the required loops for compensation. The core-loss current is obtained by dividing the primary induced voltage by the core-loss resistance. Finally, the estimated voltages across the primary and secondary windings are added to the measured secondary voltage for compensation. The scheme can significantly improve the accuracy of a VT. The results of the performance of compensator are shown in the experimental test. The accuracy of the measurement VT improves from 1.0C class to 0.1C class. The scheme can help to significantly reduce the required core cross section of a measurement VT in an electrical energy system.

Higher-order schemes for the Laplace transformation method for parabolic problems

KAUST Repository

Douglas, C.

2011-01-01

In this paper we solve linear parabolic problems using the three stage noble algorithms. First, the time discretization is approximated using the Laplace transformation method, which is both parallel in time (and can be in space, too) and extremely high order convergent. Second, higher-order compact schemes of order four and six are used for the the spatial discretization. Finally, the discretized linear algebraic systems are solved using multigrid to show the actual convergence rate for numerical examples, which are compared to other numerical solution methods. © 2011 Springer-Verlag.

An Efficient Offloading Scheme For MEC System Considering Delay and Energy Consumption

Science.gov (United States)

Sun, Yanhua; Hao, Zhe; Zhang, Yanhua

2018-01-01

With the increasing numbers of mobile devices, mobile edge computing (MEC) which provides cloud computing capabilities proximate to mobile devices in 5G networks has been envisioned as a promising paradigm to enhance users experience. In this paper, we investigate a joint consideration of delay and energy consumption offloading scheme (JCDE) for MEC system in 5G heterogeneous networks. An optimization is formulated to minimize the delay as well as energy consumption of the offloading system, which the delay and energy consumption of transmitting and calculating tasks are taken into account. We adopt an iterative greedy algorithm to solve the optimization problem. Furthermore, simulations were carried out to validate the utility and effectiveness of our proposed scheme. The effect of parameter variations on the system is analysed as well. Numerical results demonstrate delay and energy efficiency promotion of our proposed scheme compared with another paper’s scheme.

Determination analysis of energy conservation standards for distribution transformers

Energy Technology Data Exchange (ETDEWEB)

Barnes, P.R.; Van Dyke, J.W.; McConnell, B.W.; Das, S.

1996-07-01

This report contains information for US DOE to use in making a determination on proposing energy conservation standards for distribution transformers as required by the Energy Policy Act of 1992. Potential for saving energy with more efficient liquid-immersed and dry-type distribution transformers could be significant because these transformers account for an estimated 140 billion kWh of the annual energy lost in the delivery of electricity. Objective was to determine whether energy conservation standards for distribution transformers would have the potential for significant energy savings, be technically feasible, and be economically justified from a national perspective. It was found that energy conservation for distribution transformers would be technically and economically feasible. Based on the energy conservation options analyzed, 3.6-13.7 quads of energy could be saved from 2000 to 2030.

Contribution of promoting the green residence assessment scheme to energy saving

International Nuclear Information System (INIS)

Huang, Zhiyu; Yuan, Hongping; Shen, Liyin

2012-01-01

Green residence development has been one of the important strategies for promoting sustainable urban development. Governments throughout the world have been encouraging property developers to deliver green properties. In line with this development, governments have been implementing various assessment programs to certify green residential buildings with the aim of contributing to sustainable urban development. With reference to the Chinese construction practice, this paper examines the effectiveness of the green residence assessment scheme toward its defined aim through investigating the contents and procedures of the green residence assessment scheme by referring to the practices of Chongqing city in western China. Based on the results of five case studies and five semi-structured interviews, this study reveals the significant contribution from implementing the green residence assessment scheme particularly to energy saving in residential buildings. Further, the green residence assessment scheme promotes the application of green building materials and green construction technologies in the entire process of delivering and operating residential buildings. The findings provide valuable references for further investigating alternative methods to achieve better energy saving in developing residential buildings. - Highlights: ► Energy saving in residence development is important for sustainable urban development. ► Green residence assessment scheme contributes significantly to energy saving in residences. ► Green residence assessment promotes application of environmentally friendly building materials and technologies

Numerical schemes for explosion hazards

International Nuclear Information System (INIS)

Therme, Nicolas

2015-01-01

In nuclear facilities, internal or external explosions can cause confinement breaches and radioactive materials release in the environment. Hence, modeling such phenomena is crucial for safety matters. Blast waves resulting from explosions are modeled by the system of Euler equations for compressible flows, whereas Navier-Stokes equations with reactive source terms and level set techniques are used to simulate the propagation of flame front during the deflagration phase. The purpose of this thesis is to contribute to the creation of efficient numerical schemes to solve these complex models. The work presented here focuses on two major aspects: first, the development of consistent schemes for the Euler equations, then the buildup of reliable schemes for the front propagation. In both cases, explicit in time schemes are used, but we also introduce a pressure correction scheme for the Euler equations. Staggered discretization is used in space. It is based on the internal energy formulation of the Euler system, which insures its positivity and avoids tedious discretization of the total energy over staggered grids. A discrete kinetic energy balance is derived from the scheme and a source term is added in the discrete internal energy balance equation to preserve the exact total energy balance at the limit. High order methods of MUSCL type are used in the discrete convective operators, based solely on material velocity. They lead to positivity of density and internal energy under CFL conditions. This ensures that the total energy cannot grow and we can furthermore derive a discrete entropy inequality. Under stability assumptions of the discrete L8 and BV norms of the scheme's solutions one can prove that a sequence of converging discrete solutions necessarily converges towards the weak solution of the Euler system. Besides it satisfies a weak entropy inequality at the limit. Concerning the front propagation, we transform the flame front evolution equation (the so called

Green-Frag: Energy-Efficient Frame Fragmentation Scheme for Wireless Sensor Networks

KAUST Repository

Daghistani, Anas H.

2013-05-15

Power management is an active area of research in wireless sensor networks (WSNs). Efficient power management is necessary because WSNs are battery-operated devices that can be deployed in mission-critical applications. From the communications perspective, one main approach to reduce energy is to maximize throughput so the data can be transmitted in a short amount of time. Frame fragmentation techniques aim to achieve higher throughput by reducing retransmissions. Using experiments on a WSN testbed, we show that frame fragmentation helps to reduce energy consumption. We then study and compare recent frame fragmentation schemes to find the most energy-efficient scheme. Our main contribution is to propose a new frame fragmentation scheme that is optimized to be energy efficient, which is originated from the chosen frame fragmentation scheme. This new energy-efficient frame fragmentation protocol is called (Green-Frag). Green-Frag uses an algorithm that gives sensor nodes the ability to transmit data with optimal transmit power and optimal frame structure based on environmental conditions. Green-Frag takes into consideration the channel conditions, interference patterns and level, as well as the distance between sender and receiver. The thesis discusses various design and implementation considerations for Green-Frag. Also, it shows empirical results of comparing Green-Frag with other frame fragmentation protocols in terms of energy efficiency. Green-Frag performance results shows that it is capable of choosing the best transmit according to the channel conditions. Subsequently, Green-Frag achieves the least energy consumption in all environmental conditions.

Promoting renewable energy through capacity markets: An analysis of the Russian support scheme

International Nuclear Information System (INIS)

Boute, Anatole

2012-01-01

Most existing support schemes aim to stimulate the deployment of renewable energy sources in the electricity sector on the basis of the electricity output (MW h) of renewable energy installations. Support is anchored in the electricity commodity market. In contrast to this established approach, Russia intends to promote renewable energy through the capacity market. The idea is to remunerate investors for the installed capacity (MW) of their installations, in particular for the availability of their installations to produce electricity. This article argues that, contrary to the implicit consensus, a capacity-based approach to supporting renewable energy can provide an alternative to the current output-based schemes. Capacity-based schemes limit the incentive that the operators of renewable energy installations currently have under output-based schemes to deliver electricity to the grid even in periods of low demand. These schemes also provide investors with a more predictable income flow. However, to be successful, the regulation of capacity supply – currently designed for flexible power plants – needs to accommodate the specific production patterns of variable renewable energy installations. This paper examines ways to overcome this challenge in Russia and provides more general conclusions on the complex interaction between capacity markets and renewable energy investments.

Optimal Planning Method of On-load Capacity Regulating Distribution Transformers in Urban Distribution Networks after Electric Energy Replacement Considering Uncertainties

Directory of Open Access Journals (Sweden)

Yu Su

2018-06-01

Full Text Available Electric energy replacement is the umbrella term for the use of electric energy to replace oil (e.g., electric automobiles, coal (e.g., electric heating, and gas (e.g., electric cooking appliances, which increases the electrical load peak, causing greater valley/peak differences. On-load capacity regulating distribution transformers have been used to deal with loads with great valley/peak differences, so reasonably replacing conventional distribution transformers with on-load capacity regulating distribution transformers can effectively cope with load changes after electric energy replacement and reduce the no-load losses of distribution transformers. Before planning for on-load capacity regulating distribution transformers, the nodal effective load considering uncertainties within the life cycle after electric energy replacement was obtained by a Monte Carlo method. Then, according to the loss relation between on-load capacity regulating distribution transformers and conventional distribution transformers, three characteristic indexes of annual continuous apparent power curve and replacement criteria for on-load capacity regulating distribution transformers were put forward in this paper, and a set of distribution transformer replaceable points was obtained. Next, based on cost benefit analysis, a planning model of on-load capacity regulating distribution transformers which consists of investment profitability index within the life cycle, investment cost recouping index and capacity regulating cost index was put forward. The branch and bound method was used to solve the planning model within replaceable point set to obtain upgrading and reconstruction scheme of distribution transformers under a certain investment. Finally, planning analysis of on-load capacity regulating distribution transformers was carried out for electric energy replacement points in one urban distribution network under three scenes: certain load, uncertain load and nodal

Static and dynamic efficiency of white certificate schemes

International Nuclear Information System (INIS)

Giraudet, L.G.; Finon, D.

2011-01-01

White Certificate Schemes mandate energy companies to promote energy efficiency through flexibility mechanisms, including the trading of energy savings. They can be characterized as a quantity-based, baseline-and-credit system for the diffusion of energy efficient technologies. This paper compares experiences with White Certificate Schemes in Great Britain, Italy and France, in order to identify the basic drivers of each, and ultimately offer an original interpretation as an adaptive instrument, in the sense that it can take different forms in response to specific institutional contexts. A first analysis shows that Schemes perform well in terms of static efficiency, i.e. they are cost-effective and generate net social benefits over the period considered, though with large discrepancies rooted in different technological potentials. Regarding dynamic efficiency, i.e. the ability to induce and sustain technological change over the long haul, market transformation occurred in Great Britain, but was poorly incentivized in Italy and France by inadequate compliance cost recovery rules. Substantial organizational change has occurred in every country, mainly by strengthening vertical relationships between obliged parties and upstream businesses. Overall, the obligation (rather than the market component) drives the early phases of the Schemes. (authors)

Distributed multi-agent scheme for reactive power management with renewable energy

International Nuclear Information System (INIS)

Rahman, M.S.; Mahmud, M.A.; Pota, H.R.; Hossain, M.J.

2014-01-01

Highlights: • A distributed multi-agent scheme is proposed to enhance the dynamic voltage stability. • A control agent is designed where control actions are performed through PI controller. • Proposed scheme is compared with the conventional approach with DSTATCOM. • Proposed scheme adapts the capability of estimation and control under various operating conditions. - Abstract: This paper presents a new distributed multi-agent scheme for reactive power management in smart coordinated distribution networks with renewable energy sources (RESs) to enhance the dynamic voltage stability, which is mainly based on controlling distributed static synchronous compensators (DSTATCOMs). The proposed control scheme is incorporated in a multi-agent framework where the intelligent agents simultaneously coordinate with each other and represent various physical models to provide information and energy flow among different physical processes. The reactive power is estimated from the topology of distribution networks and with this information, necessary control actions are performed through the proposed proportional integral (PI) controller. The performance of the proposed scheme is evaluated on a 8-bus distribution network under various operating conditions. The performance of the proposed scheme is validated through simulation results and these results are compared to that of conventional PI-based DSTATCOM control scheme. From simulation results, it is found that the distributed MAS provides excellence performance for improving voltage profiles by managing reactive power in a smarter way

Energy balance in the transformation centers

International Nuclear Information System (INIS)

Alvim, Carlos Feu; Ferreira, Omar Campos; Eidelman, Frida.

2005-01-01

Carbon balance is an important instrument to identify the emission sources of greenhouse effect gases. Since energy use and transformation are fundamental for increasing these gases in the atmosphere, the carbon balance survey can be used to identify sectors and fuels to which priority should be given regarding emissions mitigation. In the case of transformation centers (installations where primary or secondary sources are converted into sub-products or other energy form) the balance indicated some problems regarding the Brazilian inventory calculation. Problems concerning the National Energy Balance data used here were also identified. (author)

An Energy Decaying Scheme for Nonlinear Dynamics of Shells

Science.gov (United States)

Bottasso, Carlo L.; Bauchau, Olivier A.; Choi, Jou-Young; Bushnell, Dennis M. (Technical Monitor)

2000-01-01

A novel integration scheme for nonlinear dynamics of geometrically exact shells is developed based on the inextensible director assumption. The new algorithm is designed so as to imply the strict decay of the system total mechanical energy at each time step, and consequently unconditional stability is achieved in the nonlinear regime. Furthermore, the scheme features tunable high frequency numerical damping and it is therefore stiffly accurate. The method is tested for a finite element spatial formulation of shells based on mixed interpolations of strain tensorial components and on a two-parameter representation of director rotations. The robustness of the, scheme is illustrated with the help of numerical examples.

77 FR 10997 - Energy Conservation Program: Energy Conservation Standards for Distribution Transformers; Correction

Science.gov (United States)

2012-02-24

... Conservation Program: Energy Conservation Standards for Distribution Transformers; Correction AGENCY: Office of... standards for distribution transformers. It was recently discovered that values in certain tables of the...,'' including distribution transformers. The Energy Policy Act of 1992 (EPACT 1992), Public Law 102-486, amended...

Challenging obduracy : How local communities transform the energy system

NARCIS (Netherlands)

Van Der Schoor, Tineke; Van Lente, Harro; Scholtens, Bert; Peine, Alex

2016-01-01

The transformation from the current energy system to a decentralized renewable energy system requires the transformation of communities into energy neutral or even energy producing communities. Increasingly, citizens become 'prosumers' and pool their resources to start a local energy initiative. In

Market-based support schemes for renewable energy sources

NARCIS (Netherlands)

Fagiani, R.

2014-01-01

The European Union set ambitious goals regarding the production of electricity from renewable energy sources and the majority of European governments have implemented policies stimulating investments in such technologies. Support schemes differ in many aspects, not only in their effectivity and

Total energy calculations for structural phase transformations

International Nuclear Information System (INIS)

Ye, Y.Y.; Chan, C.T.; Ho, K.M.; Harmon, B.N.

1990-01-01

The structural integrity and physical properties of crystalline solids are frequently limited or enhanced by the occurrence of phase transformations. Martensitic transformations involve the collective displacement of atoms from one ordered state to another. Modern methods to determine the microscopic electronic changes as the atoms move are now accurate enough to evaluate the very small energy differences involved. Extensive first principles calculations for the prototypical martensitic transformation from body-centered cubic (bcc) to closepacked 9R structure in sodium metal are described. The minimum energy coordinate or configuration path between the bcc and 9R structures is determined as well as paths to other competing close-packed structures. The energy barriers and important anharmonic interactions are identified and general conclusions drawn. The calculational methods used to solve the Schrodinger equation include pseudopotentials, fast Fourier transforms, efficient matrix diagnonalization, and supercells with many atoms

Design and simulation of a fuel cell hybrid emergency power system for a more electric aircraft: Evaluation of energy management schemes

Science.gov (United States)

Njoya Motapon, Souleman

. The energy management schemes are compared based on the following criteria: the hydrogen consumption, the state of charges of the batteries and supercapacitors and the overall system efficiency. Moreover the stress on each energy source, which impacts their life cycle, are measured using a new approach based on the wavelet transform of their instantaneous power. A simulation model and an experimental test bench are developed to validate all analysis and performances. The main results obtained are as follows: the state machine control scheme provided a slightly better efficiency and stresses on the batteries and supercapacitors. The classical PI control and the proposed scheme had the lowest fuel consumption and more use of the battery energy. As expected, the lowest fuel cell stress and lowest use of the battery energy was achieved with the frequency decoupling and fuzzy logic scheme, but at the expense of more fuel consumption and lower overall efficiency. The DC bus or supercapacitor voltage was maintained nearly constant for all the schemes. Also, the proposed strategy performed slightly better than the ECMS in terms of efficiency and fuel consumption, with an increase in fuel economy by 3 %. The energy management scheme suitable for a MEA emergency system should be a multischeme EMS such that each scheme is chosen based on a specific criterion to prioritize. As an example, depending on the operating life of each energy source, the energy management strategy can be chosen to either minimise the stress on the fuel cell system, the battery system or supercapacitor system, hence maximizing the life cycle of the hybrid power system. Also if the target is to reduce the fuel consumption, the proposed or the classical PI strategies are better alternatives.

The regional ground-based wind energy scheme of Pays-de-la-Loire: project, Assessment of the consultation on the regional wind energy project, final version, Prefect decree bearing approval of the regional ground-based wind energy scheme of Pays-de-la-Loire

International Nuclear Information System (INIS)

2012-08-01

This document first presents the regional wind energy scheme (SRE) as a framework for ground-based wind energy development, and as the wind energy component of the regional climate air energy scheme (SRCAE), briefly presents the elaboration approach, and indicates the legal scope of this scheme. The next part outlines the high rate development of wind energy in the Pays-de-la-Loire region. The third part reports the identification, analysis and assessment of areas of interest for the development of wind energy. Finally, the objective of this development by 2020 is estimated

Energy Aware Cluster Based Routing Scheme For Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Roy Sohini

2015-09-01

Full Text Available Wireless Sensor Network (WSN has emerged as an important supplement to the modern wireless communication systems due to its wide range of applications. The recent researches are facing the various challenges of the sensor network more gracefully. However, energy efficiency has still remained a matter of concern for the researches. Meeting the countless security needs, timely data delivery and taking a quick action, efficient route selection and multi-path routing etc. can only be achieved at the cost of energy. Hierarchical routing is more useful in this regard. The proposed algorithm Energy Aware Cluster Based Routing Scheme (EACBRS aims at conserving energy with the help of hierarchical routing by calculating the optimum number of cluster heads for the network, selecting energy-efficient route to the sink and by offering congestion control. Simulation results prove that EACBRS performs better than existing hierarchical routing algorithms like Distributed Energy-Efficient Clustering (DEEC algorithm for heterogeneous wireless sensor networks and Energy Efficient Heterogeneous Clustered scheme for Wireless Sensor Network (EEHC.

Traffic-aware energy saving scheme with modularization supporting in TWDM-PON

Science.gov (United States)

Xiong, Yu; Sun, Peng; Liu, Chuanbo; Guan, Jianjun

2017-01-01

Time and wavelength division multiplexed passive optical network (TWDM-PON) is considered to be a primary solution for next-generation passive optical network stage 2 (NG-PON2). Due to the feature of multi-wavelength transmission of TWDM-PON, some of the transmitters/receivers at the optical line terminal (OLT) could be shut down to reduce the energy consumption. Therefore, a novel scheme called traffic-aware energy saving scheme with modularization supporting is proposed. Through establishing the modular energy consumption model of OLT, the wavelength transmitters/receivers at OLT could be switched on or shut down adaptively depending on sensing the status of network traffic load, thus the energy consumption of OLT will be effectively reduced. Furthermore, exploring the technology of optical network unit (ONU) modularization, each module of ONU could be switched to sleep or active mode independently in order to reduce the energy consumption of ONU. Simultaneously, the polling sequence of ONU could be changed dynamically via sensing the packet arrival time. In order to guarantee the delay performance of network traffic, the sub-cycle division strategy is designed to transmit the real-time traffic preferentially. Finally, simulation results verify that the proposed scheme is able to reduce the energy consumption of the network while maintaining the traffic delay performance.

A New Pricing Scheme for Controlling Energy Storage Devices in Future Smart Grid

Directory of Open Access Journals (Sweden)

Jingwei Zhu

2014-01-01

Full Text Available Improvement of the overall efficiency of energy infrastructure is one of the main anticipated benefits of the deployment of smart grid technology. Advancement in energy storage technology and two-way communication in the electric network are indispensable components to achieve such a vision, while efficient pricing schemes and appropriate storage management are also essential. In this paper, we propose a universal pricing scheme which permits one to indirectly control the energy storage devices in the grid to achieve a more desirable aggregate demand profile that meets a particular target of the grid operator such as energy generation cost minimization and carbon emission reduction. Such a pricing scheme can potentially be applied to control the behavior of energy storage devices installed for integration of intermittent renewable energy sources that have permission to grid connection and will have broader applications as an increasing number of novel and low-cost energy storage technologies emerge.

Transformation between divacancy defects induced by an energy pulse in graphene.

Science.gov (United States)

Xia, Jun; Liu, XiaoYi; Zhou, Wei; Wang, FengChao; Wu, HengAn

2016-07-08

The mutual transformations among the four typical divacancy defects induced by a high-energy pulse were studied via molecular dynamics simulation. Our study revealed all six possible mutual transformations and found that defects transformed by absorbing energy to overcome the energy barrier with bonding, debonding, and bond rotations. The reversibility of defect transformations was also investigated by potential energy analysis. The energy difference was found to greatly influence the transformation reversibility. The direct transformation path was irreversible if the energy difference was too large. We also studied the correlation between the transformation probability and the input energy. It was found that the transformation probability had a local maxima at an optimal input energy. The introduction of defects and their structural evolutions are important for tailoring the exceptional properties and thereby performances of graphene-based devices, such as nanoporous membranes for the filtration and desalination of water.

A Novel Scheme for an Energy Efficient Internet of Things Based on Wireless Sensor Networks.

Science.gov (United States)

Rani, Shalli; Talwar, Rajneesh; Malhotra, Jyoteesh; Ahmed, Syed Hassan; Sarkar, Mahasweta; Song, Houbing

2015-11-12

One of the emerging networking standards that gap between the physical world and the cyber one is the Internet of Things. In the Internet of Things, smart objects communicate with each other, data are gathered and certain requests of users are satisfied by different queried data. The development of energy efficient schemes for the IoT is a challenging issue as the IoT becomes more complex due to its large scale the current techniques of wireless sensor networks cannot be applied directly to the IoT. To achieve the green networked IoT, this paper addresses energy efficiency issues by proposing a novel deployment scheme. This scheme, introduces: (1) a hierarchical network design; (2) a model for the energy efficient IoT; (3) a minimum energy consumption transmission algorithm to implement the optimal model. The simulation results show that the new scheme is more energy efficient and flexible than traditional WSN schemes and consequently it can be implemented for efficient communication in the IoT.

Financing schemes increasing energy efficiency and renewable energy use in public and private buildings. Comparative study

International Nuclear Information System (INIS)

2014-03-01

resources to financial engineering and creation of innovative financing schemes that will help them keep the money spent on energy near home. They strive for sustainable, long-term financing solutions capable to generate large-scale investments. Indeed, financing energy transition will require strong technical, financial, legal and coordination skills and expertise in local authorities. Many different players at all levels of governance have already tested and implemented successful innovative financing schemes. However, the existing and emerging financing solutions remain isolated and not well known. Energy Cities - the European association of local authorities in energy transition - aims at strengthening the skills of local authorities in this field and facilitating the exchange of their experiences so that successful schemes can be more easily replicated all over the EU and beyond. Thus, Energy Cities identified 9 existing local, regional and national financing schemes aiming at increasing energy efficiency and renewable energy use in public and private buildings, which are usually the biggest energy consumer at local level. They are presented in this study. The financing schemes have been selected with the aim to present a myriad of different solutions that are implemented to address the same problem: - Local investment funds (Almada in Portugal, Amsterdam in the Netherlands and Region Centre in France). - Local public and semi-public companies (Ile de France and Rhone-Alpes Regions in France). - Revolving funds linked to grants and soft-loan schemes (Lithuania, Estonia, Brussels-Capital Region, Delft in the Netherlands)

A Novel Image Encryption Scheme Based on Self-Synchronous Chaotic Stream Cipher and Wavelet Transform

Directory of Open Access Journals (Sweden)

Chunlei Fan

2018-06-01

Full Text Available In this paper, a novel image encryption scheme is proposed for the secure transmission of image data. A self-synchronous chaotic stream cipher is designed with the purpose of resisting active attack and ensures the limited error propagation of image data. Two-dimensional discrete wavelet transform and Arnold mapping are used to scramble the pixel value of the original image. A four-dimensional hyperchaotic system with four positive Lyapunov exponents serve as the chaotic sequence generator of the self-synchronous stream cipher in order to enhance the security and complexity of the image encryption system. Finally, the simulation experiment results show that this image encryption scheme is both reliable and secure.

Variational data assimilation schemes for transport and transformation models of atmospheric chemistry

Science.gov (United States)

Penenko, Alexey; Penenko, Vladimir; Tsvetova, Elena; Antokhin, Pavel

2016-04-01

The work is devoted to data assimilation algorithm for atmospheric chemistry transport and transformation models. In the work a control function is introduced into the model source term (emission rate) to provide flexibility to adjust to data. This function is evaluated as the constrained minimum of the target functional combining a control function norm with a norm of the misfit between measured data and its model-simulated analog. Transport and transformation processes model is acting as a constraint. The constrained minimization problem is solved with Euler-Lagrange variational principle [1] which allows reducing it to a system of direct, adjoint and control function estimate relations. This provides a physically-plausible structure of the resulting analysis without model error covariance matrices that are sought within conventional approaches to data assimilation. High dimensionality of the atmospheric chemistry models and a real-time mode of operation demand for computational efficiency of the data assimilation algorithms. Computational issues with complicated models can be solved by using a splitting technique. Within this approach a complex model is split to a set of relatively independent simpler models equipped with a coupling procedure. In a fine-grained approach data assimilation is carried out quasi-independently on the separate splitting stages with shared measurement data [2]. In integrated schemes data assimilation is carried out with respect to the split model as a whole. We compare the two approaches both theoretically and numerically. Data assimilation on the transport stage is carried out with a direct algorithm without iterations. Different algorithms to assimilate data on nonlinear transformation stage are compared. In the work we compare data assimilation results for both artificial and real measurement data. With these data we study the impact of transformation processes and data assimilation to the performance of the modeling system [3]. The

A New Pricing Scheme for Controlling Energy Storage Devices in Future Smart Grid

OpenAIRE

Zhu, Jingwei; Chen, Michael Z. Q.; Du, Baozhu

2014-01-01

Improvement of the overall efficiency of energy infrastructure is one of the main anticipated benefits of the deployment of smart grid technology. Advancement in energy storage technology and two-way communication in the electric network are indispensable components to achieve such a vision, while efficient pricing schemes and appropriate storage management are also essential. In this paper, we propose a universal pricing scheme which permits one to indirectly control the energy storage devic...

An Adaption Broadcast Radius-Based Code Dissemination Scheme for Low Energy Wireless Sensor Networks.

Science.gov (United States)

Yu, Shidi; Liu, Xiao; Liu, Anfeng; Xiong, Naixue; Cai, Zhiping; Wang, Tian

2018-05-10

Due to the Software Defined Network (SDN) technology, Wireless Sensor Networks (WSNs) are getting wider application prospects for sensor nodes that can get new functions after updating program codes. The issue of disseminating program codes to every node in the network with minimum delay and energy consumption have been formulated and investigated in the literature. The minimum-transmission broadcast (MTB) problem, which aims to reduce broadcast redundancy, has been well studied in WSNs where the broadcast radius is assumed to be fixed in the whole network. In this paper, an Adaption Broadcast Radius-based Code Dissemination (ABRCD) scheme is proposed to reduce delay and improve energy efficiency in duty cycle-based WSNs. In the ABCRD scheme, a larger broadcast radius is set in areas with more energy left, generating more optimized performance than previous schemes. Thus: (1) with a larger broadcast radius, program codes can reach the edge of network from the source in fewer hops, decreasing the number of broadcasts and at the same time, delay. (2) As the ABRCD scheme adopts a larger broadcast radius for some nodes, program codes can be transmitted to more nodes in one broadcast transmission, diminishing the number of broadcasts. (3) The larger radius in the ABRCD scheme causes more energy consumption of some transmitting nodes, but radius enlarging is only conducted in areas with an energy surplus, and energy consumption in the hot-spots can be reduced instead due to some nodes transmitting data directly to sink without forwarding by nodes in the original hot-spot, thus energy consumption can almost reach a balance and network lifetime can be prolonged. The proposed ABRCD scheme first assigns a broadcast radius, which doesn’t affect the network lifetime, to nodes having different distance to the code source, then provides an algorithm to construct a broadcast backbone. In the end, a comprehensive performance analysis and simulation result shows that the proposed

An Adaption Broadcast Radius-Based Code Dissemination Scheme for Low Energy Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Shidi Yu

2018-05-01

Full Text Available Due to the Software Defined Network (SDN technology, Wireless Sensor Networks (WSNs are getting wider application prospects for sensor nodes that can get new functions after updating program codes. The issue of disseminating program codes to every node in the network with minimum delay and energy consumption have been formulated and investigated in the literature. The minimum-transmission broadcast (MTB problem, which aims to reduce broadcast redundancy, has been well studied in WSNs where the broadcast radius is assumed to be fixed in the whole network. In this paper, an Adaption Broadcast Radius-based Code Dissemination (ABRCD scheme is proposed to reduce delay and improve energy efficiency in duty cycle-based WSNs. In the ABCRD scheme, a larger broadcast radius is set in areas with more energy left, generating more optimized performance than previous schemes. Thus: (1 with a larger broadcast radius, program codes can reach the edge of network from the source in fewer hops, decreasing the number of broadcasts and at the same time, delay. (2 As the ABRCD scheme adopts a larger broadcast radius for some nodes, program codes can be transmitted to more nodes in one broadcast transmission, diminishing the number of broadcasts. (3 The larger radius in the ABRCD scheme causes more energy consumption of some transmitting nodes, but radius enlarging is only conducted in areas with an energy surplus, and energy consumption in the hot-spots can be reduced instead due to some nodes transmitting data directly to sink without forwarding by nodes in the original hot-spot, thus energy consumption can almost reach a balance and network lifetime can be prolonged. The proposed ABRCD scheme first assigns a broadcast radius, which doesn’t affect the network lifetime, to nodes having different distance to the code source, then provides an algorithm to construct a broadcast backbone. In the end, a comprehensive performance analysis and simulation result shows that

Analysing the interactions between renewable energy promotion and energy efficiency support schemes: The impact of different instruments and design elements

International Nuclear Information System (INIS)

Rio, Pablo del

2010-01-01

CO 2 emissions reduction, renewable energy deployment and energy efficiency are three main energy/environmental goals, particularly in Europe. Their relevance has led to the implementation of support schemes in these realms. Their coexistence may lead to overlaps, synergies and conflicts between them. The aim of this paper is to analyse the interactions between energy efficiency measures and renewable energy promotion, whereas previous analyses have focused on the interactions between emissions trading schemes (ETS) and energy efficiency measures and ETS and renewable energy promotion schemes. Furthermore, the analysis in this paper transcends the 'certificate' debate (i.e., tradable green and white certificates) and considers other instruments, particularly feed-in tariffs for renewable electricity. The goal is to identify positive and negative interactions between energy efficiency and renewable electricity promotion and to assess whether the choice of specific instruments and design elements within those instruments affects the results of the interactions.

Regulatory changes to renewable energy support schemes: An international investment law perspective

OpenAIRE

Paleckaite, Gintare

2014-01-01

Thesist analyzes how regulatory changes related to renewable energy investment support schemes can be perceived under international investment law standards and how possible decisions of international investment law tribunals could impact investment in this sector. This research is based on case studies of two states: Spain and the Czech Republic and claims against them. These cases will assist in analyzing the effects of the amendment/revocation of renewable energy support schemes. Answers t...

A Novel Scheme for an Energy Efficient Internet of Things Based on Wireless Sensor Networks

Science.gov (United States)

Rani, Shalli; Talwar, Rajneesh; Malhotra, Jyoteesh; Ahmed, Syed Hassan; Sarkar, Mahasweta; Song, Houbing

2015-01-01

One of the emerging networking standards that gap between the physical world and the cyber one is the Internet of Things. In the Internet of Things, smart objects communicate with each other, data are gathered and certain requests of users are satisfied by different queried data. The development of energy efficient schemes for the IoT is a challenging issue as the IoT becomes more complex due to its large scale the current techniques of wireless sensor networks cannot be applied directly to the IoT. To achieve the green networked IoT, this paper addresses energy efficiency issues by proposing a novel deployment scheme. This scheme, introduces: (1) a hierarchical network design; (2) a model for the energy efficient IoT; (3) a minimum energy consumption transmission algorithm to implement the optimal model. The simulation results show that the new scheme is more energy efficient and flexible than traditional WSN schemes and consequently it can be implemented for efficient communication in the IoT. PMID:26569260

A Novel Scheme for an Energy Efficient Internet of Things Based on Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Shalli Rani

2015-11-01

Full Text Available One of the emerging networking standards that gap between the physical world and the cyber one is the Internet of Things. In the Internet of Things, smart objects communicate with each other, data are gathered and certain requests of users are satisfied by different queried data. The development of energy efficient schemes for the IoT is a challenging issue as the IoT becomes more complex due to its large scale the current techniques of wireless sensor networks cannot be applied directly to the IoT. To achieve the green networked IoT, this paper addresses energy efficiency issues by proposing a novel deployment scheme. This scheme, introduces: (1 a hierarchical network design; (2 a model for the energy efficient IoT; (3 a minimum energy consumption transmission algorithm to implement the optimal model. The simulation results show that the new scheme is more energy efficient and flexible than traditional WSN schemes and consequently it can be implemented for efficient communication in the IoT.

Application of the symplectic finite-difference time-domain scheme to electromagnetic simulation

International Nuclear Information System (INIS)

Sha, Wei; Huang, Zhixiang; Wu, Xianliang; Chen, Mingsheng

2007-01-01

An explicit fourth-order finite-difference time-domain (FDTD) scheme using the symplectic integrator is applied to electromagnetic simulation. A feasible numerical implementation of the symplectic FDTD (SFDTD) scheme is specified. In particular, new strategies for the air-dielectric interface treatment and the near-to-far-field (NFF) transformation are presented. By using the SFDTD scheme, both the radiation and the scattering of three-dimensional objects are computed. Furthermore, the energy-conserving characteristic hold for the SFDTD scheme is verified under long-term simulation. Numerical results suggest that the SFDTD scheme is more efficient than the traditional FDTD method and other high-order methods, and can save computational resources

Energy-Efficient Optimization for HARQ Schemes over Time-Correlated Fading Channels

KAUST Repository

Shi, Zheng

2018-03-19

Energy efficiency of three common hybrid automatic repeat request (HARQ) schemes including Type I HARQ, HARQ with chase combining (HARQ-CC) and HARQ with incremental redundancy (HARQ-IR), is analyzed and joint power allocation and rate selection to maximize the energy efficiency is investigated in this paper. Unlike prior literature, time-correlated fading channels is considered and two widely concerned quality of service (QoS) constraints, i.e., outage and goodput constraints, are also considered in the optimization, which further differentiates this work from prior ones. Using a unified expression of asymptotic outage probabilities, optimal transmission powers and optimal rate are derived in closed-forms to maximize the energy efficiency while satisfying the QoS constraints. These closed-form solutions then enable a thorough analysis of the maximal energy efficiencies of various HARQ schemes. It is revealed that with low outage constraint, the maximal energy efficiency achieved by Type I HARQ is $\\\\frac{1}{4\\\\ln2}$ bits/J, while HARQ-CC and HARQ-IR can achieve the same maximal energy efficiency as $\\\\frac{\\\\kappa_\\\\infty}{4\\\\ln2}$ bits/J where $\\\\kappa_\\\\infty = 1.6617$. Moreover, time correlation in the fading channels has a negative impact on the energy efficiency, while large maximal allowable number of transmissions is favorable for the improvement of energy efficiency. The effectiveness of the energy-efficient optimization is verified by extensive simulations and the results also show that HARQ-CC can achieve the best tradeoff between energy efficiency and spectral efficiency among the three HARQ schemes.

An Energy-Aware Hybrid ARQ Scheme with Multi-ACKs for Data Sensing Wireless Sensor Networks.

Science.gov (United States)

Zhang, Jinhuan; Long, Jun

2017-06-12

Wireless sensor networks (WSNs) are one of the important supporting technologies of edge computing. In WSNs, reliable communications are essential for most applications due to the unreliability of wireless links. In addition, network lifetime is also an important performance metric and needs to be considered in many WSN studies. In the paper, an energy-aware hybrid Automatic Repeat-reQuest protocol (ARQ) scheme is proposed to ensure energy efficiency under the guarantee of network transmission reliability. In the scheme, the source node sends data packets continuously with the correct window size and it does not need to wait for the acknowledgement (ACK) confirmation for each data packet. When the destination receives K data packets, it will return multiple copies of one ACK for confirmation to avoid ACK packet loss. The energy consumption of each node in flat circle network applying the proposed scheme is statistical analyzed and the cases under which it is more energy efficiency than the original scheme is discussed. Moreover, how to select parameters of the scheme is addressed to extend the network lifetime under the constraint of the network reliability. In addition, the energy efficiency of the proposed schemes is evaluated. Simulation results are presented to demonstrate that a node energy consumption reduction could be gained and the network lifetime is prolonged.

New schemes for high-voltage pulsed generators based on stepped transmission lines

International Nuclear Information System (INIS)

Bossamykin, V.S.; Gordeev, V.S.; Pavlovskii, A.I.

1993-01-01

Wave processes were analyzed from the point of effective energy delivery in pulsed power systems based on transmission lines. A series of new schemes for the pulsed generators based on multistage stepped transmission lines both with the capacitive and inductive energy storage was found. These devices can provide voltage or current transformation up to 5-10 times due to wave processes if stage's characteristic impedances are in a certain correlation. The schemes suggested can be widely applied in the new powerful pulsed power accelerators. The theoretical conclusions are justified experimentally

Efficient JPEG 2000 Image Compression Scheme for Multihop Wireless Networks

Directory of Open Access Journals (Sweden)

Halim Sghaier

2011-08-01

Full Text Available When using wireless sensor networks for real-time data transmission, some critical points should be considered. Restricted computational power, reduced memory, narrow bandwidth and energy supplied present strong limits in sensor nodes. Therefore, maximizing network lifetime and minimizing energy consumption are always optimization goals. To overcome the computation and energy limitation of individual sensor nodes during image transmission, an energy efficient image transport scheme is proposed, taking advantage of JPEG2000 still image compression standard using MATLAB and C from Jasper. JPEG2000 provides a practical set of features, not necessarily available in the previous standards. These features were achieved using techniques: the discrete wavelet transform (DWT, and embedded block coding with optimized truncation (EBCOT. Performance of the proposed image transport scheme is investigated with respect to image quality and energy consumption. Simulation results are presented and show that the proposed scheme optimizes network lifetime and reduces significantly the amount of required memory by analyzing the functional influence of each parameter of this distributed image compression algorithm.

A new tailored scheme for the support of renewable energies in developing countries

International Nuclear Information System (INIS)

Moner-Girona, Magda

2009-01-01

Historically the promotion of renewable energy technologies in isolated areas has involved international donors or governments subsidising the initial capital investment. This paper proposes an alternative support mechanism for remote villages based on the generation of renewable electricity. This communication presents an evaluation of the Renewable Energy Premium Tariff (RPT) scheme, a locally adapted variation of the Feed-in Tariff tailored for decentralised grids of developing countries. The RPT scheme stimulates the deployment of renewable energy technologies by paying for renewable electricity generated. A good-quality performance is secured since the support is given based on the electricity produced by renewables, not for the initial capital investment. The mechanism has been designed to provide a cost-effective scheme for the introduction of renewable energy technologies to remote villages, to provide sustainable and affordable electricity to local users, to make renewable energy projects attractive to policy-makers, and concurrently decrease financial risk to attract private sector investment. (author)

77 FR 7281 - Energy Conservation Program: Energy Conservation Standards for Distribution Transformers

Science.gov (United States)

2012-02-10

... Electrical Efficiencies for all Liquid-Immersed Distribution Transformer Equipment Classes (Compliance... ``customers.'' Customers refer to electric utilities in the case of liquid-immersed transformers, and to... for Determining Energy Efficiency for Distribution Transformers'' published by the National Electrical...

Analysing the interactions between renewable energy promotion and energy efficiency support schemes: The impact of different instruments and design elements

Energy Technology Data Exchange (ETDEWEB)

Rio, Pablo del, E-mail: pablo.delrio@cchs.csic.e [Instituto de Politicas y Bienes Publicos, Consejo Superior de Investigaciones Cientificas (CSIC), C/Albasanz 26-28, 28037 Madrid (Spain)

2010-09-15

CO{sub 2} emissions reduction, renewable energy deployment and energy efficiency are three main energy/environmental goals, particularly in Europe. Their relevance has led to the implementation of support schemes in these realms. Their coexistence may lead to overlaps, synergies and conflicts between them. The aim of this paper is to analyse the interactions between energy efficiency measures and renewable energy promotion, whereas previous analyses have focused on the interactions between emissions trading schemes (ETS) and energy efficiency measures and ETS and renewable energy promotion schemes. Furthermore, the analysis in this paper transcends the 'certificate' debate (i.e., tradable green and white certificates) and considers other instruments, particularly feed-in tariffs for renewable electricity. The goal is to identify positive and negative interactions between energy efficiency and renewable electricity promotion and to assess whether the choice of specific instruments and design elements within those instruments affects the results of the interactions.

Analysing the interactions between renewable energy promotion and energy efficiency support schemes. The impact of different instruments and design elements

Energy Technology Data Exchange (ETDEWEB)

Del Rio, Pablo [Instituto de Politicas y Bienes Publicos, Consejo Superior de Investigaciones Cientificas (CSIC), C/Albasanz 26-28, 28037 Madrid (Spain)

2010-09-15

CO{sub 2} emissions reduction, renewable energy deployment and energy efficiency are three main energy/environmental goals, particularly in Europe. Their relevance has led to the implementation of support schemes in these realms. Their coexistence may lead to overlaps, synergies and conflicts between them. The aim of this paper is to analyse the interactions between energy efficiency measures and renewable energy promotion, whereas previous analyses have focused on the interactions between emissions trading schemes (ETS) and energy efficiency measures and ETS and renewable energy promotion schemes. Furthermore, the analysis in this paper transcends the certificate debate (i.e., tradable green and white certificates) and considers other instruments, particularly feed-in tariffs for renewable electricity. The goal is to identify positive and negative interactions between energy efficiency and renewable electricity promotion and to assess whether the choice of specific instruments and design elements within those instruments affects the results of the interactions. (author)

How to transform local energy systems towards bioenergy? Three strategy models for transformation

International Nuclear Information System (INIS)

Martensson, Kjell; Westerberg, Karin

2007-01-01

During the last decades, the actors within the energy sector in Sweden-as well as in many other countries-have faced increasing demands to transform the energy system towards ecological sustainability. In Sweden these demands have led to numerous policies and economic incentives promoting the use of renewables (which in the Swedish discourse often also includes a connotation of 'indigenous energy sources'), and especially the promotion of bioenergy. To be successful, however, these policies and economic incentives need to be interpreted and adapted to different local contexts and translated into actual transformation processes. In Sweden the municipal authorities have played an important role as interpreters of such institutional frameworks and implementers of local transformation processes. In this article, we re-construct three transformation processes implemented by local municipal authorities, chiselling out the different strategy models developed through them. We argue that such re-constructions help to make visible the different and complex interactions between national institutional frameworks and local contexts as well as interactions within such local contexts. We hope that the strategy models presented can contribute to the understanding of the different kinds of local actions that can foster a further implementation of bioenergy into the energy system

Response of multiferroic composites inferred from a fast-Fourier-transform-based numerical scheme

International Nuclear Information System (INIS)

Brenner, Renald; Bravo-Castillero, Julián

2010-01-01

The effective response and the local fields within periodic magneto-electric multiferroic composites are investigated by means of a numerical scheme based on fast Fourier transforms. This computational framework relies on the iterative resolution of coupled series expansions for the magnetic, electric and strain fields. By using an augmented Lagrangian formulation, a simple and robust procedure which makes use of the uncoupled Green operators for the elastic, electrostatics and magnetostatics problems is proposed. Its accuracy is assessed in the cases of laminated and fibrous two-phase composites for which analytical solutions exist

Electronic Power Transformer for Power Distribution Networks

Directory of Open Access Journals (Sweden)

Ermuraсhi Iu.V.

2017-12-01

Full Text Available Reducing losses in electricity distribution networks is a current technical problem. This issue also has social and environmental aspects. As a promising solution one can examine the direct distribution from the medium voltage power network using new equipment based on the use of power electronics. The aim of the paper is to propose and argue an innovative technical solution for the realization of the Solid State Transformer (SST in order to decrease the number of energy transformation stages compared to the known solutions, simplifying the topology of the functional scheme with the reduction of production costs and the loss of energy in transformers used in electrical distribution networks. It is proposed the solution of simplifying the topology of the AC/AC electronic transformer by reducing the number of passive electronic components (resistors, inductors, capacitors and active (transistors. The inverter of the SST transformer ensures the switching mode of the transistors, using for this purpose the inductance of the magnetic leakage flux of the high frequency transformer. The robustness of the laboratory sample of the SST 10 / 0.22 kV transformer with the power of 20 kW was manufactured and tested. Testing of the laboratory sample confirmed the functionality of the proposed scheme and the possibility of switching of the transistors to at zero current (ZCS mode with the reduction of the energy losses. In the proposed converter a single high-frequency transformer with a simplified construction with two windings is used, which reduces its mass and the cost of making the transformer. The reduction in the manufacturing cost of the converter is also due to the decrease in the number of links between the functional elements.

Energy systems transformation.

Science.gov (United States)

Dangerman, A T C Jérôme; Schellnhuber, Hans Joachim

2013-02-12

The contemporary industrial metabolism is not sustainable. Critical problems arise at both the input and the output side of the complex: Although affordable fossil fuels and mineral resources are declining, the waste products of the current production and consumption schemes (especially CO(2) emissions, particulate air pollution, and radioactive residua) cause increasing environmental and social costs. Most challenges are associated with the incumbent energy economy that is unlikely to subsist. However, the crucial question is whether a swift transition to its sustainable alternative, based on renewable sources, can be achieved. The answer requires a deep analysis of the structural conditions responsible for the rigidity of the fossil-nuclear energy system. We argue that the resilience of the fossil-nuclear energy system results mainly from a dynamic lock-in pattern known in operations research as the "Success to the Successful" mode. The present way of generating, distributing, and consuming energy--the largest business on Earth--expands through a combination of factors such as the longevity of pertinent infrastructure, the information technology revolution, the growth of the global population, and even the recent financial crises: Renewable-energy industries evidently suffer more than the conventional-energy industries under recession conditions. Our study tries to elucidate the archetypical traits of the lock-in pattern and to assess the respective importance of the factors involved. In particular, we identify modern corporate law as a crucial system element that thus far has been largely ignored. Our analysis indicates that the rigidity of the existing energy economy would be reduced considerably by the assignment of unlimited liabilities to the shareholders.

Examination of Spectral Transformations on Spectral Mixture Analysis

Science.gov (United States)

Deng, Y.; Wu, C.

2018-04-01

While many spectral transformation techniques have been applied on spectral mixture analysis (SMA), few study examined their necessity and applicability. This paper focused on exploring the difference between spectrally transformed schemes and untransformed scheme to find out which transformed scheme performed better in SMA. In particular, nine spectrally transformed schemes as well as untransformed scheme were examined in two study areas. Each transformed scheme was tested 100 times using different endmember classes' spectra under the endmember model of vegetation- high albedo impervious surface area-low albedo impervious surface area-soil (V-ISAh-ISAl-S). Performance of each scheme was assessed based on mean absolute error (MAE). Statistical analysis technique, Paired-Samples T test, was applied to test the significance of mean MAEs' difference between transformed and untransformed schemes. Results demonstrated that only NSMA could exceed the untransformed scheme in all study areas. Some transformed schemes showed unstable performance since they outperformed the untransformed scheme in one area but weakened the SMA result in another region.

Green-Frag: Energy-Efficient Frame Fragmentation Scheme for Wireless Sensor Networks

KAUST Repository

Daghistani, Anas H.

2013-01-01

that is optimized to be energy efficient, which is originated from the chosen frame fragmentation scheme. This new energy-efficient frame fragmentation protocol is called (Green-Frag). Green-Frag uses an algorithm that gives sensor nodes the ability to transmit data

Fierz transformations and renormalization schemes for fourquark operators

Directory of Open Access Journals (Sweden)

Garron Nicolas

2018-01-01

Full Text Available It has been shown that the choice of renormalization scheme is crucial for four-quark operators, in particular for neutral kaon mixing beyond the Standard Model. In the context of SMOM schemes, the choice of projector is not unique and is part of the definition of the renormalisation scheme. I present the non-diagonal Fierz relations which relate some of these projectors.

Analysis of Program Obfuscation Schemes with Variable Encoding Technique

Science.gov (United States)

Fukushima, Kazuhide; Kiyomoto, Shinsaku; Tanaka, Toshiaki; Sakurai, Kouichi

Program analysis techniques have improved steadily over the past several decades, and software obfuscation schemes have come to be used in many commercial programs. A software obfuscation scheme transforms an original program or a binary file into an obfuscated program that is more complicated and difficult to analyze, while preserving its functionality. However, the security of obfuscation schemes has not been properly evaluated. In this paper, we analyze obfuscation schemes in order to clarify the advantages of our scheme, the XOR-encoding scheme. First, we more clearly define five types of attack models that we defined previously, and define quantitative resistance to these attacks. Then, we compare the security, functionality and efficiency of three obfuscation schemes with encoding variables: (1) Sato et al.'s scheme with linear transformation, (2) our previous scheme with affine transformation, and (3) the XOR-encoding scheme. We show that the XOR-encoding scheme is superior with regard to the following two points: (1) the XOR-encoding scheme is more secure against a data-dependency attack and a brute force attack than our previous scheme, and is as secure against an information-collecting attack and an inverse transformation attack as our previous scheme, (2) the XOR-encoding scheme does not restrict the calculable ranges of programs and the loss of efficiency is less than in our previous scheme.

A new cooperative MIMO scheme based on SM for energy-efficiency improvement in wireless sensor network.

Science.gov (United States)

Peng, Yuyang; Choi, Jaeho

2014-01-01

Improving the energy efficiency in wireless sensor networks (WSN) has attracted considerable attention nowadays. The multiple-input multiple-output (MIMO) technique has been proved as a good candidate for improving the energy efficiency, but it may not be feasible in WSN which is due to the size limitation of the sensor node. As a solution, the cooperative multiple-input multiple-output (CMIMO) technique overcomes this constraint and shows a dramatically good performance. In this paper, a new CMIMO scheme based on the spatial modulation (SM) technique named CMIMO-SM is proposed for energy-efficiency improvement. We first establish the system model of CMIMO-SM. Based on this model, the transmission approach is introduced graphically. In order to evaluate the performance of the proposed scheme, a detailed analysis in terms of energy consumption per bit of the proposed scheme compared with the conventional CMIMO is presented. Later, under the guide of this new scheme we extend our proposed CMIMO-SM to a multihop clustered WSN for further achieving energy efficiency by finding an optimal hop-length. Equidistant hop as the traditional scheme will be compared in this paper. Results from the simulations and numerical experiments indicate that by the use of the proposed scheme, significant savings in terms of total energy consumption can be achieved. Combining the proposed scheme with monitoring sensor node will provide a good performance in arbitrary deployed WSN such as forest fire detection system.

Energy-saving scheme based on downstream packet scheduling in ethernet passive optical networks

Science.gov (United States)

Zhang, Lincong; Liu, Yejun; Guo, Lei; Gong, Xiaoxue

2013-03-01

With increasing network sizes, the energy consumption of Passive Optical Networks (PONs) has grown significantly. Therefore, it is important to design effective energy-saving schemes in PONs. Generally, energy-saving schemes have focused on sleeping the low-loaded Optical Network Units (ONUs), which tends to bring large packet delays. Further, the traditional ONU sleep modes are not capable of sleeping the transmitter and receiver independently, though they are not required to transmit or receive packets. Clearly, this approach contributes to wasted energy. Thus, in this paper, we propose an Energy-Saving scheme that is based on downstream Packet Scheduling (ESPS) in Ethernet PON (EPON). First, we design both an algorithm and a rule for downstream packet scheduling at the inter- and intra-ONU levels, respectively, to reduce the downstream packet delay. After that, we propose a hybrid sleep mode that contains not only ONU deep sleep mode but also independent sleep modes for the transmitter and the receiver. This ensures that the energy consumed by the ONUs is minimal. To realize the hybrid sleep mode, a modified GATE control message is designed that involves 10 time points for sleep processes. In ESPS, the 10 time points are calculated according to the allocated bandwidths in both the upstream and the downstream. The simulation results show that ESPS outperforms traditional Upstream Centric Scheduling (UCS) scheme in terms of energy consumption and the average delay for both real-time and non-real-time packets downstream. The simulation results also show that the average energy consumption of each ONU in larger-sized networks is less than that in smaller-sized networks; hence, our ESPS is better suited for larger-sized networks.

Gleer: A Novel Gini-Based Energy Balancing Scheme for Mobile Botnet Retopology

Directory of Open Access Journals (Sweden)

Yichuan Wang

2018-01-01

Full Text Available Mobile botnet has recently evolved due to the rapid growth of smartphone technologies. Unlike legacy botnets, mobile devices are characterized by limited power capacity, calculation capabilities, and wide communication methods. As such, the logical topology structure and communication mode have to be redesigned for mobile botnets to narrow energy gap and lower the reduction speed of nodes. In this paper, we try to design a novel Gini-based energy balancing scheme (Gleer for the atomic network, which is a fundamental component of the heterogeneous multilayer mobile botnet. Firstly, for each operation cycle, we utilize the dynamic energy threshold to categorize atomic network into two groups. Then, the Gini coefficient is introduced to estimate botnet energy gap and to regulate the probability for each node to be picked as a region C&C server. Experimental results indicate that our proposed method can effectively prolong the botnet lifetime and prevent the reduction of network size. Meanwhile, the stealthiness of botnet with Gleer scheme is analyzed from users’ perspective, and results show that the proposed scheme works well in the reduction of user’ detection awareness.

Electronic Power Transformer Control Strategy in Wind Energy Conversion Systems for Low Voltage Ride-through Capability Enhancement of Directly Driven Wind Turbines with Permanent Magnet Synchronous Generators (D-PMSGs

Directory of Open Access Journals (Sweden)

Hui Huang

2014-11-01

Full Text Available This paper investigates the use of an Electronic Power Transformer (EPT incorporated with an energy storage system to smooth the wind power fluctuations and enhance the low voltage ride-through (LVRT capability of directly driven wind turbines with permanent magnet synchronous generators (D-PMSGs. The decoupled control schemes of the system, including the grid side converter control scheme, generator side converter control scheme and the control scheme of the energy storage system, are presented in detail. Under normal operating conditions, the energy storage system absorbs the high frequency component of the D-PMSG output power to smooth the wind power fluctuations. Under grid fault conditions, the energy storage system absorbs the redundant power, which could not be transferred to the grid by the EPT, to help the D-PMSG to ride through low voltage conditions. This coordinated control strategy is validated by simulation studies using MATLAB/Simulink. With the proposed control strategy, the output wind power quality is improved and the D-PMSG can ride through severe grid fault conditions.

Energy efficient appliance choice under the EU labeling scheme

Energy Technology Data Exchange (ETDEWEB)

Mills, Bradford F.; Schleich, Joachim [Fraunhofer-Institut fuer System- und Innovationsforschung (ISI), Karlsruhe (Germany)

2010-02-15

This paper extends the existing empirical literature on consumers' choices when exposed to energy labeling schemes by allowing choices to depend on household socio-economic characteristics, technology-related factors, behavioral and motivational factors, and country conditions in a multi-country analysis. To account for a possible knowledge-based selection bias, the econometric model distinguishes label class knowledge from the energy class choice decision. As a general finding, most covariates show stronger relationships with knowledge of labeling class than with the choice of energy efficiency class. Four factors show particularly strong and expected influences on label class awareness. First, general awareness of household energy use and energy saving technologies spills over into awareness of the energy class of specific appliances. Second, socioeconomic characteristics mater, as education increases label class awareness and older age reduces awareness. Third, economic incentives matter, as stated economic importance of energy saving and higher country electricity prices both generate greater label awareness. By contrast, stated concerns about global warming do not appear to have a broad impact on awareness. Fourth, effective country implementation of the labeling scheme raises label awareness. More surprisingly, most factors that promote awareness of appliance energy classes have a limited influence on actual appliance energy class choice. Efficient energy behavior in the household is not strongly linked to appliance energy class choice. Socio-economic characteristics also have limited influence. This finding is inline with other studies that find that household socio-economic characteristics have relatively weak associations with the adoption of energy efficient technologies (Mills and Schleich 2010, Brohmann et al. 2009). In fact, with education it is vocational degrees rather than university degrees that are positively associated with the propensity to

Calculation of transformers leakage reactance using electromagnetic energy technique

International Nuclear Information System (INIS)

Feiz, J.; Mohseni, H.; Sabet Marzooghi, S.; Naderian Jahromi, A.

2004-01-01

Determination of transformer leakage reactance using magnetic cores has long been an area of interest to engineers involved in the design of power and distribution transformers. This is required for predicting the performance of transformers before actual assembly of the transformers. In this paper a closed form solution technique applicable to the leakage reactance calculations for transformers is presented. An emphasis is on the development of a simple method to calculate the leakage reactance of the distribution transformers and smaller transformers. Energy technique procedure for computing the leakage reactances in distribution transformers is presented. This method is very efficient compared with the use of flux element and image technique and is also remarkably accurate. Examples of calculated leakage inductances and the short circuit impedance are given for illustration. For validation, the results are compared with the results obtained using test. This paper presents a novel technique for calculation of the leakage inductance in different parts of the transformer using the electromagnetic stored energy

Energy-preserving H1-Galerkin schemes for shallow water wave equations with peakon solutions

International Nuclear Information System (INIS)

Miyatake, Yuto; Matsuo, Takayasu

2012-01-01

New energy-preserving Galerkin schemes for the Camassa–Holm and the Degasperis–Procesi equations which model shallow water waves are presented. The schemes can be implemented only with cheap H 1 elements, which is expected to be sufficient to catch the characteristic peakon solutions. The keys of the derivation are the Hamiltonian structures of the equations and an L 2 -projection technique newly employed in the present Letter to mimic the Hamiltonian structures in a discrete setting, so that the desired energy-preserving property rightly follows. Numerical examples confirm the effectiveness of the schemes. -- Highlights: ► Numerical integration of the Camassa–Holm and Degasperis–Procesi equation. ► New energy-preserving Galerkin schemes for these equations are proposed. ► They can be implemented only with P1 elements. ► They well capture the characteristic peakon solutions over long time. ► The keys are the Hamiltonian structures and L 2 -projection technique.

Co-ordination of renewable energy support schemes in the EU

Energy Technology Data Exchange (ETDEWEB)

Grenaa Jensen, S.; Morthorst, P.E. [Risoe National Lab., Roskilde (Denmark)

2007-05-15

This paper illustrates the effect that can be observed when support schemes for renewable energy are regionalised. Two theoretical examples are used to explain interactive effects on, e.g., price of power, conditions for conventional power producers, and changes in import and export of power. The results are based on a deterministic partial equilibrium model, where two cases are studied. The first case covers countries with regional power markets that also regionalise their tradable green certificate (TGC) support schemes. The second, countries with separate national power markets that regionalise their TGC-support schemes. The main findings indicate that the almost ideal situation exists if the region prior to regionalising their RES-E support scheme already has a common liberalised power market. In this case, introduction of a common TGC-support scheme for renewable technologies will lead to more efficient sitings of renewable plants, improving economic and environmental performance of the total power system. But if no such common power market exits, regionalising their TGC-schemes might, due to interactions, introduce distortions in the conventional power system. Thus, contrary to intentions, we might in this case end up in a system that is far from optimal with regard to efficiency and emissions. (au)

Co-ordination of renewable energy support schemes in the EU

International Nuclear Information System (INIS)

Grenaa Jensen, S.; Morthorst, P.E.

2007-01-01

This paper illustrates the effect that can be observed when support schemes for renewable energy are regionalised. Two theoretical examples are used to explain interactive effects on, e.g., price of power, conditions for conventional power producers, and changes in import and export of power. The results are based on a deterministic partial equilibrium model, where two cases are studied. The first case covers countries with regional power markets that also regionalise their tradable green certificate (TGC) support schemes. The second, countries with separate national power markets that regionalise their TGC-support schemes. The main findings indicate that the almost ideal situation exists if the region prior to regionalising their RES-E support scheme already has a common liberalised power market. In this case, introduction of a common TGC-support scheme for renewable technologies will lead to more efficient sitings of renewable plants, improving economic and environmental performance of the total power system. But if no such common power market exits, regionalising their TGC-schemes might, due to interactions, introduce distortions in the conventional power system. Thus, contrary to intentions, we might in this case end up in a system that is far from optimal with regard to efficiency and emissions. (au)

Quantification of energy savings from Ireland's Home Energy Saving scheme. An ex post billing analysis

Energy Technology Data Exchange (ETDEWEB)

Scheer, J.; Clancy, M.; Ni Hogain, S. [Sustainable Energy Authority of Ireland, Wilton Park House, Wilton Terrace, Dublin 2 (Ireland)

2013-02-15

This paper quantifies the energy savings realised by a sample of participants in the Sustainable Energy Authority of Ireland's Home Energy Saving (HES) residential retrofit scheme (currently branded as the Better Energy Homes scheme), through an ex post billing analysis. The billing data are used to evaluate: (1) the reduction in gas consumption of the sample between pre- (2008) and post- (2010) scheme participation when compared to the gas consumption of a control group, (2) an estimate of the shortfall when this result is compared to engineering-type ex ante savings estimates and (3) the degree to which these results may apply to the wider population. All dwellings in the study underwent energy efficiency improvements, including insulation upgrades (wall and/or roof), installation of high-efficiency boilers and/or improved heating controls, as part of the HES scheme. Metered gas use data for the 210 households were obtained from meter operators for a number of years preceding dwelling upgrades and for a post-intervention period of 1 year. Dwelling characteristics and some household behavioural data were obtained through a survey of the sample. The gas network operator provided anonymised data on gas usage for 640,000 customers collected over the same period as the HES sample. Dwelling type data provided with the population dataset enabled matching with the HES sample to increase the internal validity of the comparison between the control (matched population data) and the treatment (HES sample). Using a difference-in-difference methodology, the change in demand of the sample was compared with that of the matched population subset of gas-using customers in Ireland over the same time period. The mean reduction in gas demand as a result of energy efficiency upgrades for the HES sample is estimated as 21 % or 3,664{+-}603 kWh between 2008 and 2010. An ex ante estimate of average energy savings, based on engineering calculations (u value reductions and improved boiler

Energy-Efficient Relay Selection Scheme for Physical Layer Security in Cognitive Radio Networks

Directory of Open Access Journals (Sweden)

Li Jiang

2015-01-01

selection and dynamic power allocation in order to maximize SC and to minimize energy consumption. Moreover, we consider finite-state Markov channels and residual relay energy in the relay selection and power allocation process. Specifically, the formulation of the proposed relay selection and power allocation scheme is based on the restless bandit problem, which is solved by the primal-dual index heuristic algorithm. Additionally, the obtained optimal relay selection policy has an indexability property that dramatically reduces the computational complexity. Numerical results are presented to show that our proposed scheme has the maximum SC and minimum energy consumption compared to the existing ones.

Ambiguity attacks on robust blind image watermarking scheme based on redundant discrete wavelet transform and singular value decomposition

Directory of Open Access Journals (Sweden)

Khaled Loukhaoukha

2017-12-01

Full Text Available Among emergent applications of digital watermarking are copyright protection and proof of ownership. Recently, Makbol and Khoo (2013 have proposed for these applications a new robust blind image watermarking scheme based on the redundant discrete wavelet transform (RDWT and the singular value decomposition (SVD. In this paper, we present two ambiguity attacks on this algorithm that have shown that this algorithm fails when used to provide robustness applications like owner identification, proof of ownership, and transaction tracking. Keywords: Ambiguity attack, Image watermarking, Singular value decomposition, Redundant discrete wavelet transform

Determination of minimum impact parameter by modified touching spheres schemes for intermediate energy Coulomb excitation experiments

International Nuclear Information System (INIS)

Kumar, Rajiv; Sharma, Shagun; Singh, Pradeep; Kharab, Rajesh

2016-01-01

The energy-independent touching spheres schemes commonly used for the determination of the safe minimum value of the impact parameter for Coulomb excitation experiments are modified through the inclusion of an energy-dependent term. The touching spheres+3fm scheme after modification emerges out to be the best one while touching spheres+4fm scheme is found to be better in its unmodified form. (orig.)

ETEEM- Extended Traffic Aware Energy Efficient MAC Scheme for WSNs

OpenAIRE

Younas Khan; Sheeraz Ahmed; Fakhri Alam Khan; Imran Ahmad; Saqib Shahid Rahim; M. Irfan Khattak

2016-01-01

Idle listening issue arises when a sensor node listens to medium despite the absence of data which results in consumption of energy. ETEEM is a variant of Traffic Aware Energy Efficient MAC protocol (TEEM) which focuses on energy optimization due to reduced idle listening time and much lesser overhead on energy sources. It uses a novel scheme for using idle listening time of sensor nodes. The nodes are only active for small amount of time and most of the time, will be in sleep mode when no da...

Comparative study on γ energy spectrum denoise by fourier and wavelet transforms

International Nuclear Information System (INIS)

Shi Dongsheng; Di Yuming; Zhou Chunlin

2007-01-01

This paper introduces the basic principle of wavelet and Fourier transforms, applies wavelet transform method to denoise γ energy spectrum of 60 Co and compares it with Fourier transform method. The result of simulation with MATLAB software tool showed that as compared with traditional Fourier transform, wavelet transform has comparatively higher accuracy for γ energy spectrum denoising and is more feasible to γ energy spectrum denoising. (authors)

Quantitative schemes in energy dispersive X-ray fluorescence implemented in AXIL

International Nuclear Information System (INIS)

Tchantchane, A.; Benamar, M.A.; Tobbeche, S.

1995-01-01

E.D.X.R.F (Energy Dispersive X-ray Fluorescence) has long been used for quantitative analysis of many types of samples including environment samples. the software package AXIL (Analysis of x-ray spectra by iterative least quares) is extensively used for the spectra analysis and the quantification of x-ray spectra. It includes several methods of quantitative schemes for evaluating element concentrations. We present the general theory behind each scheme implemented into the software package. The spectra of the performance of each of these quantitative schemes. We have also investigated their performance relative to the uncertainties in the experimental parameters and sample description

EDOVE: Energy and Depth Variance-Based Opportunistic Void Avoidance Scheme for Underwater Acoustic Sensor Networks.

Science.gov (United States)

Bouk, Safdar Hussain; Ahmed, Syed Hassan; Park, Kyung-Joon; Eun, Yongsoon

2017-09-26

Underwater Acoustic Sensor Network (UASN) comes with intrinsic constraints because it is deployed in the aquatic environment and uses the acoustic signals to communicate. The examples of those constraints are long propagation delay, very limited bandwidth, high energy cost for transmission, very high signal attenuation, costly deployment and battery replacement, and so forth. Therefore, the routing schemes for UASN must take into account those characteristics to achieve energy fairness, avoid energy holes, and improve the network lifetime. The depth based forwarding schemes in literature use node's depth information to forward data towards the sink. They minimize the data packet duplication by employing the holding time strategy. However, to avoid void holes in the network, they use two hop node proximity information. In this paper, we propose the Energy and Depth variance-based Opportunistic Void avoidance (EDOVE) scheme to gain energy balancing and void avoidance in the network. EDOVE considers not only the depth parameter, but also the normalized residual energy of the one-hop nodes and the normalized depth variance of the second hop neighbors. Hence, it avoids the void regions as well as balances the network energy and increases the network lifetime. The simulation results show that the EDOVE gains more than 15 % packet delivery ratio, propagates 50 % less copies of data packet, consumes less energy, and has more lifetime than the state of the art forwarding schemes.

Energy efficient scheme for cognitive radios utilizing soft sensing

KAUST Repository

Alabbasi, AbdulRahman; Rezki, Zouheir; Shihada, Basem

2014-01-01

In this paper we propose an energy efficient cognitive radio system. Our design considers an underlaying resource allocation combined with soft sensing information to achieve a sub-optimum energy efficient system. The sub-optimality is achieved by optimizing over a channel inversion power policy instead of considering a water-filling power policy. We consider an Energy per Goodbit (EPG) metric to express the energy efficient objective function of the system and as an evaluation metric to our system performance. Since our optimization problem is not a known convex problem, we prove its convexity to guarantee its feasibility. We evaluate the proposed scheme comparing to a benchmark system through both analytical and numerical results.

Energy efficient scheme for cognitive radios utilizing soft sensing

KAUST Repository

Alabbasi, Abdulrahman

2014-04-06

In this paper we propose an energy efficient cognitive radio system. Our design considers an underlaying resource allocation combined with soft sensing information to achieve a sub-optimum energy efficient system. The sub-optimality is achieved by optimizing over a channel inversion power policy instead of considering a water-filling power policy. We consider an Energy per Goodbit (EPG) metric to express the energy efficient objective function of the system and as an evaluation metric to our system performance. Since our optimization problem is not a known convex problem, we prove its convexity to guarantee its feasibility. We evaluate the proposed scheme comparing to a benchmark system through both analytical and numerical results.

The same number of optimized parameters scheme for determining intermolecular interaction energies

DEFF Research Database (Denmark)

Kristensen, Kasper; Ettenhuber, Patrick; Eriksen, Janus Juul

2015-01-01

We propose the Same Number Of Optimized Parameters (SNOOP) scheme as an alternative to the counterpoise method for treating basis set superposition errors in calculations of intermolecular interaction energies. The key point of the SNOOP scheme is to enforce that the number of optimized wave...... as numerically. Numerical results for second-order Møller-Plesset perturbation theory (MP2) and coupled-cluster with single, double, and approximate triple excitations (CCSD(T)) show that the SNOOP scheme in general outperforms the uncorrected and counterpoise approaches. Furthermore, we show that SNOOP...

Evaluation of the Market introduction Energy Innovations (MEI) subsidy scheme; Evaluatie van de MEI-regeling

Energy Technology Data Exchange (ETDEWEB)

Wetzels, W.; Smekens, K.; Lako, P. [ECN Beleidsstudies, Petten (Netherlands); Warmenhoven, H. [De Gemeynt, Klarenbeek (Netherlands)

2012-11-15

This report contains the outcomes of an evaluation study of the Market introduction Energy Innovations (MEI) subsidy scheme. This scheme is targeted to the horticultural sector and aims to stimulate and accelerate the early market introduction of innovative energy systems in greenhouses. The subsidy scheme was initiated in 2007 and has provided subsidies twice a year since then. Based on project and data analysis, stakeholder interviews and a workshop, the evaluation concludes that the MEI scheme has made a positive contribution to the innovation process in the sector, but that the scheme could have been implemented more efficiently [Dutch] De regeling Marktintroductie energie-innovaties (MEI) is in 2007 ingesteld door het toenmalige Ministerie van Landbouw, Natuur en Voedselkwaliteit. Het doel van de MEI-regeling is het stimuleren en versnellen van de vroege marktintroductie van innovatieve energiesystemen in de glastuinbouw. ECN en De Gemeynt hebben een evaluatie uitgevoerd van de MEI-regeling. De centrale conclusie is dat de regeling een positieve bijdrage heeft geleverd aan het innovatieproces in de glastuinbouwsector.

Kramers-Kronig transform for the surface energy loss function

International Nuclear Information System (INIS)

Tan, G.L.; DeNoyer, L.K.; French, R.H.; Guittet, M.J.; Gautier-Soyer, M.

2005-01-01

A new pair of Kramers-Kronig (KK) dispersion relationships for the transformation of surface energy loss function Im[-1/(ε + 1)] has been proposed. The validity of the new surface KK transform is confirmed, using both a Lorentz oscillator model and the surface energy loss functions determined from the experimental complex dielectric function of SrTiO 3 and tungsten metal. The interband transition strength spectra (J cv ) have been derived either directly from the original complex dielectric function or from the derived dielectric function obtained from the KK transform of the surface energy loss function. The original J cv trace and post-J cv trace overlapped together for the three modes, indicating that the new surface Kramers-Kronig dispersion relationship is valid for the surface energy loss function

Multiple-image encryption via lifting wavelet transform and XOR operation based on compressive ghost imaging scheme

Science.gov (United States)

Li, Xianye; Meng, Xiangfeng; Yang, Xiulun; Wang, Yurong; Yin, Yongkai; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi

2018-03-01

A multiple-image encryption method via lifting wavelet transform (LWT) and XOR operation is proposed, which is based on a row scanning compressive ghost imaging scheme. In the encryption process, the scrambling operation is implemented for the sparse images transformed by LWT, then the XOR operation is performed on the scrambled images, and the resulting XOR images are compressed in the row scanning compressive ghost imaging, through which the ciphertext images can be detected by bucket detector arrays. During decryption, the participant who possesses his/her correct key-group, can successfully reconstruct the corresponding plaintext image by measurement key regeneration, compression algorithm reconstruction, XOR operation, sparse images recovery, and inverse LWT (iLWT). Theoretical analysis and numerical simulations validate the feasibility of the proposed method.

Outage Performance Analysis of Relay Selection Schemes in Wireless Energy Harvesting Cooperative Networks over Non-Identical Rayleigh Fading Channels.

Science.gov (United States)

Do, Nhu Tri; Bao, Vo Nguyen Quoc; An, Beongku

2016-02-26

In this paper, we study relay selection in decode-and-forward wireless energy harvesting cooperative networks. In contrast to conventional cooperative networks, the relays harvest energy from the source's radio-frequency radiation and then use that energy to forward the source information. Considering power splitting receiver architecture used at relays to harvest energy, we are concerned with the performance of two popular relay selection schemes, namely, partial relay selection (PRS) scheme and optimal relay selection (ORS) scheme. In particular, we analyze the system performance in terms of outage probability (OP) over independent and non-identical (i.n.i.d.) Rayleigh fading channels. We derive the closed-form approximations for the system outage probabilities of both schemes and validate the analysis by the Monte-Carlo simulation. The numerical results provide comprehensive performance comparison between the PRS and ORS schemes and reveal the effect of wireless energy harvesting on the outage performances of both schemes. Additionally, we also show the advantages and drawbacks of the wireless energy harvesting cooperative networks and compare to the conventional cooperative networks.

Hawking–Hayward quasi-local energy under conformal transformations

International Nuclear Information System (INIS)

Prain, Angus; Faraoni, Valerio; Lapierre-Léonard, Marianne; Vitagliano, Vincenzo

2016-01-01

We derive a formula describing the transformation of the Hawking–Hayward quasi-local energy under a conformal rescaling of the spacetime metric. A known formula for the transformation of the Misner–Sharp–Hernandez mass is recovered as a special case. (paper)

The mass-retrofitting of an energy efficient-low carbon zone: Baselining the urban regeneration strategy, vision, masterplan and redevelopment scheme

International Nuclear Information System (INIS)

Deakin, Mark; Campbell, Fiona; Reid, Alasdair

2012-01-01

This paper examines a recent attempt to reduce energy consumption and the associated levels of carbon emissions by way of and through what has been termed: “an active and integrated institutional arrangement”. That is, by the integration of a mass retrofit proposal into an urban regeneration strategy, with the vision, master-plan, programme of renewal and redevelopment scheme which is capable of transforming into an energy efficient, low carbon zone. As a case study on how institutions can plan for low energy efficient redevelopments and the possibility of low carbon zones, the paper highlights the current state of the art on mass retrofits within the residential property sector and draws particular attention to the type of baseline assessments needed to legitimate, not only the strategic value of such arrangements, but their practical worth as measures capable of meeting emission targets set under the 2008 UK Climate Bill.

Coordinated renewable energy support schemes

DEFF Research Database (Denmark)

Morthorst, P.E.; Jensen, S.G.

2006-01-01

. The first example covers countries with regional power markets that also regionalise their support schemes, the second countries with separate national power markets that regionalise their support schemes. The main findings indicate that the almost ideal situation exists if the region prior to regionalising...

Financing the energy renovation of residential buildings through soft loans and third-party investment schemes. Infinite Solutions Guidebook

International Nuclear Information System (INIS)

Schilken, Peter; Cicmanova, Jana; Turner, Ian; Van Liefland, Stijn; Kaiser, Maaike; Ethuin, Perrine; Bernair, Corinne; Bertolotti, Enzo; Mordacci, Marco; Fraval, Jacques; Beaupetit, Helene; Safiulins, Timurs; Latisevs, Jevgenijs; Wenzel, Philipp; Dehghan, Bahram; Rask Nielsen, Poul

2017-02-01

Financing the energy retrofitting of buildings is a great challenge. With investments ranging from euros 200 to euros 1,200 /m 2 (CITYnvest study, 2015), access to attractive and long-term financing is perceived as the primary barrier to carrying out ambitious energy retrofits, in particular those aiming at achieving 50-75% energy savings. In this guidebook, Energy Cities' members share their experience and guide you through the process of setting up a soft loan financing scheme. The Stuttgart's 'care-free energy renovation package' and third party investment scheme are described in detail in a dedicated case study. The guidebook is intended for local and regional authorities, energy agencies and their associations, national energy agencies, ministries and fund managers, organisations providing training to cities and regions, banks and financing institutions. In short, all organisations and actors who could be interested in replicating these financing schemes or who could support cities and regions in doing so. The guidebook consists of four chapters: Chapter 1: an introduction to soft loan schemes. Chapter 2: step-by-step guidance on how to build a soft loan financing scheme, including an overview of three already tested alternative business models. Chapter 3: summary and recommendations. Chapter 4: case studies, including Stuttgart's third party investment scheme

An Energy-Efficient Game-Theory-Based Spectrum Decision Scheme for Cognitive Radio Sensor Networks.

Science.gov (United States)

Salim, Shelly; Moh, Sangman

2016-06-30

A cognitive radio sensor network (CRSN) is a wireless sensor network in which sensor nodes are equipped with cognitive radio. In this paper, we propose an energy-efficient game-theory-based spectrum decision (EGSD) scheme for CRSNs to prolong the network lifetime. Note that energy efficiency is the most important design consideration in CRSNs because it determines the network lifetime. The central part of the EGSD scheme consists of two spectrum selection algorithms: random selection and game-theory-based selection. The EGSD scheme also includes a clustering algorithm, spectrum characterization with a Markov chain, and cluster member coordination. Our performance study shows that EGSD outperforms the existing popular framework in terms of network lifetime and coordination overhead.

Energy Stability Analysis of Some Fully Discrete Numerical Schemes for Incompressible Navier–Stokes Equations on Staggered Grids

KAUST Repository

Chen, Huangxin

2017-09-01

In this paper we consider the energy stability estimates for some fully discrete schemes which both consider time and spatial discretizations for the incompressible Navier–Stokes equations. We focus on three kinds of fully discrete schemes, i.e., the linear implicit scheme for time discretization with the finite difference method (FDM) on staggered grids for spatial discretization, pressure-correction schemes for time discretization with the FDM on staggered grids for the solutions of the decoupled velocity and pressure equations, and pressure-stabilization schemes for time discretization with the FDM on staggered grids for the solutions of the decoupled velocity and pressure equations. The energy stability estimates are obtained for the above each fully discrete scheme. The upwind scheme is used in the discretization of the convection term which plays an important role in the design of unconditionally stable discrete schemes. Numerical results are given to verify the theoretical analysis.

Neutron-energy-dependent cell survival and oncogenic transformation.

Science.gov (United States)

Miller, R C; Marino, S A; Martin, S G; Komatsu, K; Geard, C R; Brenner, D J; Hall, E J

1999-12-01

Both cell lethality and neoplastic transformation were assessed for C3H10T1/2 cells exposed to neutrons with energies from 0.040 to 13.7 MeV. Monoenergetic neutrons with energies from 0.23 to 13.7 MeV and two neutron energy spectra with average energies of 0.040 and 0.070 MeV were produced with a Van de Graaff accelerator at the Radiological Research Accelerator Facility (RARAF) in the Center for Radiological Research of Columbia University. For determination of relative biological effectiveness (RBE), cells were exposed to 250 kVp X rays. With exposures to 250 kVp X rays, both cell survival and radiation-induced oncogenic transformation were curvilinear. Irradiation of cells with neutrons at all energies resulted in linear responses as a function of dose for both biological endpoints. Results indicate a complex relationship between RBEm and neutron energy. For both survival and transformation, RBEm was greatest for cells exposed to 0.35 MeV neutrons. RBEm was significantly less at energies above or below 0.35 MeV. These results are consistent with microdosimetric expectation. These results are also compatible with current assessments of neutron radiation weighting factors for radiation protection purposes. Based on calculations of dose-averaged LET, 0.35 MeV neutrons have the greatest LET and therefore would be expected to be more biologically effective than neutrons of greater or lesser energies.

On Converting Secret Sharing Scheme to Visual Secret Sharing Scheme

Directory of Open Access Journals (Sweden)

Wang Daoshun

2010-01-01

Full Text Available Abstract Traditional Secret Sharing (SS schemes reconstruct secret exactly the same as the original one but involve complex computation. Visual Secret Sharing (VSS schemes decode the secret without computation, but each share is m times as big as the original and the quality of the reconstructed secret image is reduced. Probabilistic visual secret sharing (Prob.VSS schemes for a binary image use only one subpixel to share the secret image; however the probability of white pixels in a white area is higher than that in a black area in the reconstructed secret image. SS schemes, VSS schemes, and Prob. VSS schemes have various construction methods and advantages. This paper first presents an approach to convert (transform a -SS scheme to a -VSS scheme for greyscale images. The generation of the shadow images (shares is based on Boolean XOR operation. The secret image can be reconstructed directly by performing Boolean OR operation, as in most conventional VSS schemes. Its pixel expansion is significantly smaller than that of VSS schemes. The quality of the reconstructed images, measured by average contrast, is the same as VSS schemes. Then a novel matrix-concatenation approach is used to extend the greyscale -SS scheme to a more general case of greyscale -VSS scheme.

Energy Efficient In-network RFID Data Filtering Scheme in Wireless Sensor Networks

Science.gov (United States)

Bashir, Ali Kashif; Lim, Se-Jung; Hussain, Chauhdary Sajjad; Park, Myong-Soon

2011-01-01

RFID (Radio frequency identification) and wireless sensor networks are backbone technologies for pervasive environments. In integration of RFID and WSN, RFID data uses WSN protocols for multi-hop communications. Energy is a critical issue in WSNs; however, RFID data contains a lot of duplication. These duplications can be eliminated at the base station, but unnecessary transmissions of duplicate data within the network still occurs, which consumes nodes’ energy and affects network lifetime. In this paper, we propose an in-network RFID data filtering scheme that efficiently eliminates the duplicate data. For this we use a clustering mechanism where cluster heads eliminate duplicate data and forward filtered data towards the base station. Simulation results prove that our approach saves considerable amounts of energy in terms of communication and computational cost, compared to existing filtering schemes. PMID:22163999

Energy Efficient In-network RFID Data Filtering Scheme in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Myong-Soon Park

2011-07-01

Full Text Available RFID (Radio frequency identification and wireless sensor networks are backbone technologies for pervasive environments. In integration of RFID and WSN, RFID data uses WSN protocols for multi-hop communications. Energy is a critical issue in WSNs; however, RFID data contains a lot of duplication. These duplications can be eliminated at the base station, but unnecessary transmissions of duplicate data within the network still occurs, which consumes nodes’ energy and affects network lifetime. In this paper, we propose an in-network RFID data filtering scheme that efficiently eliminates the duplicate data. For this we use a clustering mechanism where cluster heads eliminate duplicate data and forward filtered data towards the base station. Simulation results prove that our approach saves considerable amounts of energy in terms of communication and computational cost, compared to existing filtering schemes.

A parallel 3-D discrete wavelet transform architecture using pipelined lifting scheme approach for video coding

Science.gov (United States)

Hegde, Ganapathi; Vaya, Pukhraj

2013-10-01

This article presents a parallel architecture for 3-D discrete wavelet transform (3-DDWT). The proposed design is based on the 1-D pipelined lifting scheme. The architecture is fully scalable beyond the present coherent Daubechies filter bank (9, 7). This 3-DDWT architecture has advantages such as no group of pictures restriction and reduced memory referencing. It offers low power consumption, low latency and high throughput. The computing technique is based on the concept that lifting scheme minimises the storage requirement. The application specific integrated circuit implementation of the proposed architecture is done by synthesising it using 65 nm Taiwan Semiconductor Manufacturing Company standard cell library. It offers a speed of 486 MHz with a power consumption of 2.56 mW. This architecture is suitable for real-time video compression even with large frame dimensions.

UD-WCMA: An Energy Estimation and Forecast Scheme for Solar Powered Wireless Sensor Networks

KAUST Repository

Dehwah, Ahmad H.

2017-04-11

Energy estimation and forecast represents an important role for energy management in solar-powered wireless sensor networks (WSNs). In general, the energy in such networks is managed over a finite time horizon in the future based on input solar power forecasts to enable continuous operation of the WSNs and achieve the sensing objectives while ensuring that no node runs out of energy. In this article, we propose a dynamic version of the weather conditioned moving average technique (UD-WCMA) to estimate and predict the variations of the solar power in a wireless sensor network. The presented approach combines the information from the real-time measurement data and a set of stored profiles representing the energy patterns in the WSNs location to update the prediction model. The UD-WCMA scheme is based on adaptive weighting parameters depending on the weather changes which makes it flexible compared to the existing estimation schemes without any precalibration. A performance analysis has been performed considering real irradiance profiles to assess the UD-WCMA prediction accuracy. Comparative numerical tests to standard forecasting schemes (EWMA, WCMA, and Pro-Energy) shows the outperformance of the new algorithm. The experimental validation has proven the interesting features of the UD-WCMA in real time low power sensor nodes.

Measuring transformers in energy measurement technology

International Nuclear Information System (INIS)

Vock, E.

2009-01-01

This article takes a look at the use of measurement transformers in energy measurement installations in the light of electricity market liberalisation. Such equipment is quoted as being long living and capital-intensive. Increasing requirements on the installation of measurement equipment between partners in a liberalised market are examined. The requirements placed by electricity market legislation on the systems for the various grid voltage levels are discussed. Both current and voltage measurement transformers are looked at and the requirements placed on their accuracy are discussed in detail.

Self-powered suspension criterion and energy regeneration implementation scheme of motor-driven active suspension

Science.gov (United States)

Yan, Shuai; Sun, Weichao

2017-09-01

Active suspension systems have advantages on mitigating the effects of vehicle vibration caused by road roughness, which are one of the most important component parts in influencing the performances of vehicles. However, high amount of energy consumption restricts the application of active suspension systems. From the point of energy saving, this paper presents a self-powered criterion of the active suspension system to judge whether a motor-driven suspension can be self-powered or not, and then a motor parameter condition is developed as a reference to design a self-powered suspension. An energy regeneration implementation scheme is subsequently proposed to make the active suspension which has the potential to be self-powered achieve energy-saving target in the real application. In this implementation scheme, operating electric circuits are designed based on different working status of the actuator and power source and it is realizable to accumulate energy from road vibration and supply energy to the actuator by switching corresponding electric circuits. To apply the self-powered suspension criterion and energy regeneration implementation scheme, an active suspension system is designed with a constrained H∞ controller and calculation results indicate that it has the capability to be self-powered. Simulation results show that the performances of the self-powered active suspension are nearly the same as those of the active suspension with an external energy source and can achieve energy regeneration at the same time.

Equivalence between the Energy Stable Flux Reconstruction and Filtered Discontinuous Galerkin Schemes

Science.gov (United States)

Zwanenburg, Philip; Nadarajah, Siva

2016-02-01

The aim of this paper is to demonstrate the equivalence between filtered Discontinuous Galerkin (DG) schemes and the Energy Stable Flux Reconstruction (ESFR) schemes, expanding on previous demonstrations in 1D [1] and for straight-sided elements in 3D [2]. We first derive the DG and ESFR schemes in strong form and compare the respective flux penalization terms while highlighting the implications of the fundamental assumptions for stability in the ESFR formulations, notably that all ESFR scheme correction fields can be interpreted as modally filtered DG correction fields. We present the result in the general context of all higher dimensional curvilinear element formulations. Through a demonstration that there exists a weak form of the ESFR schemes which is both discretely and analytically equivalent to the strong form, we then extend the results obtained for the strong formulations to demonstrate that ESFR schemes can be interpreted as a DG scheme in weak form where discontinuous edge flux is substituted for numerical edge flux correction. Theoretical derivations are then verified with numerical results obtained from a 2D Euler testcase with curved boundaries. Given the current choice of high-order DG-type schemes and the question as to which might be best to use for a specific application, the main significance of this work is the bridge that it provides between them. Clearly outlining the similarities between the schemes results in the important conclusion that it is always less efficient to use ESFR schemes, as opposed to the weak DG scheme, when solving problems implicitly.

Counter-Based Broadcast Scheme Considering Reachability, Network Density, and Energy Efficiency for Wireless Sensor Networks.

Science.gov (United States)

Jung, Ji-Young; Seo, Dong-Yoon; Lee, Jung-Ryun

2018-01-04

A wireless sensor network (WSN) is emerging as an innovative method for gathering information that will significantly improve the reliability and efficiency of infrastructure systems. Broadcast is a common method to disseminate information in WSNs. A variety of counter-based broadcast schemes have been proposed to mitigate the broadcast-storm problems, using the count threshold value and a random access delay. However, because of the limited propagation of the broadcast-message, there exists a trade-off in a sense that redundant retransmissions of the broadcast-message become low and energy efficiency of a node is enhanced, but reachability become low. Therefore, it is necessary to study an efficient counter-based broadcast scheme that can dynamically adjust the random access delay and count threshold value to ensure high reachability, low redundant of broadcast-messages, and low energy consumption of nodes. Thus, in this paper, we first measure the additional coverage provided by a node that receives the same broadcast-message from two neighbor nodes, in order to achieve high reachability with low redundant retransmissions of broadcast-messages. Second, we propose a new counter-based broadcast scheme considering the size of the additional coverage area, distance between the node and the broadcasting node, remaining battery of the node, and variations of the node density. Finally, we evaluate performance of the proposed scheme compared with the existing counter-based broadcast schemes. Simulation results show that the proposed scheme outperforms the existing schemes in terms of saved rebroadcasts, reachability, and total energy consumption.

Delay-Aware Program Codes Dissemination Scheme in Internet of Everything

Directory of Open Access Journals (Sweden)

Yixuan Xu

2016-01-01

Full Text Available Due to recent advancements in big data, connection technologies, and smart devices, our environment is transforming into an “Internet of Everything” (IoE environment. These smart devices can obtain new or special functions by reprogramming: upgrade their soft systems through receiving new version of program codes. However, bulk codes dissemination suffers from large delay, energy consumption, and number of retransmissions because of the unreliability of wireless links. In this paper, a delay-aware program dissemination (DAPD scheme is proposed to disseminate program codes with fast, reliable, and energy-efficient style. We observe that although total energy is limited in wireless sensor network, there exists residual energy in nodes deployed far from the base station. Therefore, DAPD scheme improves the performance of bulk codes dissemination through the following two aspects. (1 Due to the fact that a high transmitting power can significantly improve the quality of wireless links, transmitting power of sensors with more residual energy is enhanced to improve link quality. (2 Due to the fact that performance of correlated dissemination tends to degrade in a highly dynamic environment, link correlation is autonomously updated in DAPD during codes dissemination to maintain improvements brought by correlated dissemination. Theoretical analysis and experimental results show that, compared with previous work, DAPD scheme improves the dissemination performance in terms of completion time, transmission cost, and the efficiency of energy utilization.

An Energy-Efficient Game-Theory-Based Spectrum Decision Scheme for Cognitive Radio Sensor Networks

Directory of Open Access Journals (Sweden)

Shelly Salim

2016-06-01

Full Text Available A cognitive radio sensor network (CRSN is a wireless sensor network in which sensor nodes are equipped with cognitive radio. In this paper, we propose an energy-efficient game-theory-based spectrum decision (EGSD scheme for CRSNs to prolong the network lifetime. Note that energy efficiency is the most important design consideration in CRSNs because it determines the network lifetime. The central part of the EGSD scheme consists of two spectrum selection algorithms: random selection and game-theory-based selection. The EGSD scheme also includes a clustering algorithm, spectrum characterization with a Markov chain, and cluster member coordination. Our performance study shows that EGSD outperforms the existing popular framework in terms of network lifetime and coordination overhead.

Pays-de-la-Loire regional climate air energy scheme - The commitment for energy transition and climate in Pays-de-la-Loire. Environmental assessment report - Pays-de-la-Loire regional climate air energy scheme

International Nuclear Information System (INIS)

Galliard de Lavernee, Christian; Auxiette, Jacques; Potier, Valerie; Viroulaud, Lionel; Ganne, Maryse; Guevel, Vanina; Pineau, Christophe; Bretaud, Jean-Francois; Bertaud, Geraldine; Garnier, Patrick; Durr, Fabien; Bertron, Julien

2013-01-01

After a discussion of the strategic dimension of the regional climate air energy scheme (SRCAE), a first document proposes a synthetic presentation of the regional diagnosis in terms of energy consumption, greenhouse gas emissions, and renewable energy production. It discusses how to contribute to national objectives related to these issues, and gives a synthetic table of orientations. It indicates and comments areas of action for energy sobriety and efficiency and for the reduction of greenhouse gas emissions in the different sectors (agriculture, building, industry, transport and land development), for the development of renewable energies (wood-energy, methanization, wind energy, geothermal and aero-thermal energy, hydroelectricity, solar thermal and solar photovoltaic energy), for a good air quality, and for a compliance with a strategy of adaptation to climate change. A leaflet proposes a synthetic presentation of these issues (strategic orientations, regional diagnosis, and scenario by 2020). A document contains the opinion of the Environmental Authority on this scheme project. An environmental assessment report proposes a non-technical summary, a discussion of motivation for the acceptance of the SRCAE regarding objectives related to the protection of the environment, a discussion of the initial situation and perspectives of evolution of the environment, an analysis of possible noticeable effects of the SRCAE implementation, an assessment of impacts of Natura 2000, a brief discussion of measures envisaged to avoid, reduce or compensate harmful consequences of the SRCAE, and a presentation of the environmental assessment method

Phases of the energy system transformation

International Nuclear Information System (INIS)

Fischedick, Manfred; Samadi, Sascha; Hoffmann, Clemens; Henning, Hans-Martin; Pregger, Thomas; Leprich, Uwe; Schmidt, Maike

2015-01-01

The energy transition is an ambitious and highly complex process of transformation. This article presents eight theses that can help to better understand the challenges and to identify starting points for future action and to identify research needs. [de

Transaction costs of Tradable White Certificate schemes: The Energy Efficiency Commitment as case study

International Nuclear Information System (INIS)

Mundaca, Luis

2007-01-01

This paper analyses the nature and scale of transaction costs (TCs) borne by obliged parties under a 'Tradable White Certificate' (TWC) scheme. Taking the first phase of the Energy Efficiency Commitment (EEC1) in Great Britain as a case study, several sources of TCs were considered, such as search for information, persuasion of customers, negotiation with business partners, and measurement and verification activities. Information was obtained through interviews and a questionnaire distributed to obliged parties. Results show that the most significant sources of TCs were related to search for information, persuading customers and negotiating with managing agents/contractors to implement energy efficiency measures. Perceived high TCs related to contract negotiation and liability risks slightly reduced the low trading level. The scale of TCs was estimated to be around 10% and 30% of total investments costs for the lighting and insulation segments, respectively. The results indicate that, despite the presence and scale of TCs, the EEC1 scheme generated energy savings that yielded net societal benefits. Estimated financial benefits range from 0.6 to 6 p/kWh for insulation and lighting savings, respectively. When avoided external costs due to electricity savings are included, estimated economic benefits range from 3 to 8 p/kWh. Several lessons from the EEC1 can be drawn for TWC schemes. Among others, it is found that informative policy instruments to raise awareness among end-users are critical if a TWC scheme is to deliver cost-effective energy savings. In all, the nature and scale of TCs under TWC schemes will differ because of a number of endogenous and exogenous determinants

Transaction costs of Tradable White Certificate schemes: The Energy Efficiency Commitment as case study

Energy Technology Data Exchange (ETDEWEB)

Mundaca, Luis [International Institute for Industrial Environmental Economics at Lund University, Lund (Sweden)

2007-08-15

This paper analyses the nature and scale of transaction costs (TCs) borne by obliged parties under a ''Tradable White Certificate'' (TWC) scheme. Taking the first phase of the Energy Efficiency Commitment (EEC1) in Great Britain as a case study, several sources of TCs were considered, such as search for information, persuasion of customers, negotiation with business partners, and measurement and verification activities. Information was obtained through interviews and a questionnaire distributed to obliged parties. Results show that the most significant sources of TCs were related to search for information, persuading customers and negotiating with managing agents/contractors to implement energy efficiency measures. Perceived high TCs related to contract negotiation and liability risks slightly reduced the low trading level. The scale of TCs was estimated to be around 10% and 30% of total investments costs for the lighting and insulation segments, respectively. The results indicate that, despite the presence and scale of TCs, the EEC1 scheme generated energy savings that yielded net societal benefits. Estimated financial benefits range from 0.6 to 6 p/kWh for insulation and lighting savings, respectively. When avoided external costs due to electricity savings are included, estimated economic benefits range from 3 to 8 p/kWh. Several lessons from the EEC1 can be drawn for TWC schemes. Among others, it is found that informative policy instruments to raise awareness among end-users are critical if a TWC scheme is to deliver cost-effective energy savings. In all, the nature and scale of TCs under TWC schemes will differ because of a number of endogenous and exogenous determinants. (author)

A new scheme for the promotion of renewable energies in developing countries: the renewable energy regulated purchase tariff

NARCIS (Netherlands)

Moner-Girona, M.; Aulich, H.; Ahm, P.; Adelmann, P.; Bounia, A.; Fabre, E.; Fioravanti, E.; Hosini, F.; Jongerden, G.J.; Jourde, P.; Kukuczka, T.; Llamas, P.; Macias, E.; Mayer, D.; Maigne, Y.; Moner, M.; McNelis, B.; Nemac, F.; Sener, O.; Ribeiro, F.; Samak, I.; Schmid, J.; Shah, Arvind; Shanker, A.; Sark, W.G.J.H.M. van; Vallvé, X.; Wohlthat, A.; Wollny, M.; Wouters, F.

2008-01-01

The main aim of this policy-support document is to attract policy-makers attention in renewable energies deployment, offering to energy and development stakeholders an alternative subsidy-scheme to support electrification in a village-scale mini-grid based on the good performance of the renewable

A Novel Iris Segmentation Scheme

Directory of Open Access Journals (Sweden)

Chen-Chung Liu

2014-01-01

Full Text Available One of the key steps in the iris recognition system is the accurate iris segmentation from its surrounding noises including pupil, sclera, eyelashes, and eyebrows of a captured eye-image. This paper presents a novel iris segmentation scheme which utilizes the orientation matching transform to outline the outer and inner iris boundaries initially. It then employs Delogne-Kåsa circle fitting (instead of the traditional Hough transform to further eliminate the outlier points to extract a more precise iris area from an eye-image. In the extracted iris region, the proposed scheme further utilizes the differences in the intensity and positional characteristics of the iris, eyelid, and eyelashes to detect and delete these noises. The scheme is then applied on iris image database, UBIRIS.v1. The experimental results show that the presented scheme provides a more effective and efficient iris segmentation than other conventional methods.

Poynting Theorem, Relativistic Transformation of Total Energy-Momentum and Electromagnetic Energy-Momentum Tensor

Science.gov (United States)

Kholmetskii, Alexander; Missevitch, Oleg; Yarman, Tolga

2016-02-01

We address to the Poynting theorem for the bound (velocity-dependent) electromagnetic field, and demonstrate that the standard expressions for the electromagnetic energy flux and related field momentum, in general, come into the contradiction with the relativistic transformation of four-vector of total energy-momentum. We show that this inconsistency stems from the incorrect application of Poynting theorem to a system of discrete point-like charges, when the terms of self-interaction in the product {\\varvec{j}} \\cdot {\\varvec{E}} (where the current density {\\varvec{j}} and bound electric field {\\varvec{E}} are generated by the same source charge) are exogenously omitted. Implementing a transformation of the Poynting theorem to the form, where the terms of self-interaction are eliminated via Maxwell equations and vector calculus in a mathematically rigorous way (Kholmetskii et al., Phys Scr 83:055406, 2011), we obtained a novel expression for field momentum, which is fully compatible with the Lorentz transformation for total energy-momentum. The results obtained are discussed along with the novel expression for the electromagnetic energy-momentum tensor.

Outage Performance Analysis of Relay Selection Schemes in Wireless Energy Harvesting Cooperative Networks over Non-Identical Rayleigh Fading Channels †

Science.gov (United States)

Do, Nhu Tri; Bao, Vo Nguyen Quoc; An, Beongku

2016-01-01

In this paper, we study relay selection in decode-and-forward wireless energy harvesting cooperative networks. In contrast to conventional cooperative networks, the relays harvest energy from the source’s radio-frequency radiation and then use that energy to forward the source information. Considering power splitting receiver architecture used at relays to harvest energy, we are concerned with the performance of two popular relay selection schemes, namely, partial relay selection (PRS) scheme and optimal relay selection (ORS) scheme. In particular, we analyze the system performance in terms of outage probability (OP) over independent and non-identical (i.n.i.d.) Rayleigh fading channels. We derive the closed-form approximations for the system outage probabilities of both schemes and validate the analysis by the Monte-Carlo simulation. The numerical results provide comprehensive performance comparison between the PRS and ORS schemes and reveal the effect of wireless energy harvesting on the outage performances of both schemes. Additionally, we also show the advantages and drawbacks of the wireless energy harvesting cooperative networks and compare to the conventional cooperative networks. PMID:26927119

The impacts of household retrofit and domestic energy efficiency schemes: A large scale, ex post evaluation

International Nuclear Information System (INIS)

Webber, Phil; Gouldson, Andy; Kerr, Niall

2015-01-01

There is widespread interest in the ability of retrofit schemes to shape domestic energy use in order to tackle fuel poverty and reduce carbon emissions. Although much has been written on the topic, there have been few large-scale ex post evaluations of the actual impacts of such schemes. We address this by assessing domestic energy use before and after the Kirklees Warm Zone (KWZ) scheme, which by fitting insulation in 51,000 homes in the 2007–2010 period is one of the largest retrofit schemes completed in the UK to date. To do this, we develop and apply a new methodology that isolates the impacts of retrofit activity from broader background trends in energy use. The results suggest that the actual impacts of the KWZ scheme have been higher than predicted, and that the scale of any performance gaps or rebound effects have been lower than has often been assumed. They also suggest that impacts on energy use in lower income areas are consistent with predictions, but that impacts in middle and higher income areas are higher than predicted. These findings support the case for the wider and/or accelerated adoption of domestic retrofit schemes in other contexts. -- Highlights: •A large scale, ex post evaluation of the impacts of a household retrofit scheme. •A new methodology to separate retrofit impacts from background trends. •Shows impacts of retrofit have been 1.2–1.7 times higher than predicted. •Impacts as predicted in lower income areas, higher in middle and upper income areas. •Findings support the case for the wider and faster adoption of domestic retrofit

Energy efficiency optimization in distribution transformers considering Spanish distribution regulation policy

International Nuclear Information System (INIS)

Pezzini, Paola; Gomis-Bellmunt, Oriol; Frau-Valenti, Joan; Sudria-Andreu, Antoni

2010-01-01

In transmission and distribution systems, the high number of installed transformers, a loss source in networks, suggests a good potential for energy savings. This paper presents how the Spanish Distribution regulation policy, Royal Decree 222/2008, affects the overall energy efficiency in distribution transformers. The objective of a utility is the maximization of the benefit, and in case of failures, to install a chosen transformer in order to maximize the profit. Here, a novel method to optimize energy efficiency, considering the constraints set by the Spanish Distribution regulation policy, is presented; its aim is to achieve the objectives of the utility when installing new transformers. The overall energy efficiency increase is a clear result that can help in meeting the requirements of European environmental plans, such as the '20-20-20' action plan.

Efficiency and Flexibility of Fingerprint Scheme Using Partial Encryption and Discrete Wavelet Transform to Verify User in Cloud Computing.

Science.gov (United States)

Yassin, Ali A

2014-01-01

Now, the security of digital images is considered more and more essential and fingerprint plays the main role in the world of image. Furthermore, fingerprint recognition is a scheme of biometric verification that applies pattern recognition techniques depending on image of fingerprint individually. In the cloud environment, an adversary has the ability to intercept information and must be secured from eavesdroppers. Unluckily, encryption and decryption functions are slow and they are often hard. Fingerprint techniques required extra hardware and software; it is masqueraded by artificial gummy fingers (spoof attacks). Additionally, when a large number of users are being verified at the same time, the mechanism will become slow. In this paper, we employed each of the partial encryptions of user's fingerprint and discrete wavelet transform to obtain a new scheme of fingerprint verification. Moreover, our proposed scheme can overcome those problems; it does not require cost, reduces the computational supplies for huge volumes of fingerprint images, and resists well-known attacks. In addition, experimental results illustrate that our proposed scheme has a good performance of user's fingerprint verification.

High-current pulses from inductive energy stores

International Nuclear Information System (INIS)

Wipf, S.L.

1981-01-01

Superconducting inductive energy stores can be used for high power pulse supplies if a suitable current multiplication scheme is used. The concept of an inductive Marx generator is superior to a transformer. A third scheme, a variable flux linkage device, is suggested; in multiplying current it also compresses energy. Its function is in many ways analogous to that of a horsewhip. Superconductor limits indicate that peak power levels of TW can be reached for stored energies above 1 MJ

Multi-Class load balancing scheme for QoS and energy ...

African Journals Online (AJOL)

Multi-Class load balancing scheme for QoS and energy conservation in cloud computing. ... If you would like more information about how to print, save, and work with PDFs, Highwire Press provides a helpful Frequently Asked Questions about PDFs. Alternatively, you can download the PDF file directly to your computer, from ...

Benchmarking and energy management schemes in SMEs

Energy Technology Data Exchange (ETDEWEB)

Huenges Wajer, Boudewijn [SenterNovem (Netherlands); Helgerud, Hans Even [New Energy Performance AS (Norway); Lackner, Petra [Austrian Energy Agency (Austria)

2007-07-01

Many companies are reluctant to focus on energy management or to invest in energy efficiency measures. Nevertheless, there are many good examples proving that the right approach to implementing energy efficiency can very well be combined with the business-priorities of most companies. SMEs in particular can benefit from a facilitated European approach because they normally have a lack of resources and time to invest in energy efficiency. In the EU supported pilot project BESS, 60 SMEs from 11 European countries of the food and drink industries successfully tested a package of interactive instruments which offers such a facilitated approach. A number of pilot companies show a profit increase of 3 up to 10 %. The package includes a user-friendly and web based E-learning scheme for implementing energy management as well as a benchmarking module for company specific comparison of energy performance indicators. Moreover, it has several practical and tested tools to support the cycle of continuous improvement of energy efficiency in the company such as checklists, sector specific measure lists, templates for auditing and energy conservation plans. An important feature and also a key trigger for companies is the possibility for SMEs to benchmark anonymously their energy situation against others of the same sector. SMEs can participate in a unique web based benchmarking system to interactively benchmark in a way which fully guarantees confidentiality and safety of company data. Furthermore, the available data can contribute to a bottom-up approach to support the objectives of (national) monitoring and targeting and thereby also contributing to the EU Energy Efficiency and Energy Services Directive. A follow up project to expand the number of participating SMEs of various sectors is currently being developed.

Modeling and Analysis of Energy Conservation Scheme Based on Duty Cycling in Wireless Ad Hoc Sensor Network

Science.gov (United States)

Chung, Yun Won; Hwang, Ho Young

2010-01-01

In sensor network, energy conservation is one of the most critical issues since sensor nodes should perform a sensing task for a long time (e.g., lasting a few years) but the battery of them cannot be replaced in most practical situations. For this purpose, numerous energy conservation schemes have been proposed and duty cycling scheme is considered the most suitable power conservation technique, where sensor nodes alternate between states having different levels of power consumption. In order to analyze the energy consumption of energy conservation scheme based on duty cycling, it is essential to obtain the probability of each state. In this paper, we analytically derive steady state probability of sensor node states, i.e., sleep, listen, and active states, based on traffic characteristics and timer values, i.e., sleep timer, listen timer, and active timer. The effect of traffic characteristics and timer values on the steady state probability and energy consumption is analyzed in detail. Our work can provide sensor network operators guideline for selecting appropriate timer values for efficient energy conservation. The analytical methodology developed in this paper can be extended to other energy conservation schemes based on duty cycling with different sensor node states, without much difficulty. PMID:22219676

Modeling and Analysis of Energy Conservation Scheme Based on Duty Cycling in Wireless Ad Hoc Sensor Network

Directory of Open Access Journals (Sweden)

Yun Won Chung

2010-06-01

Full Text Available In sensor network, energy conservation is one of the most critical issues since sensor nodes should perform a sensing task for a long time (e.g., lasting a few years but the battery of them cannot be replaced in most practical situations. For this purpose, numerous energy conservation schemes have been proposed and duty cycling scheme is considered the most suitable power conservation technique, where sensor nodes alternate between states having different levels of power consumption. In order to analyze the energy consumption of energy conservation scheme based on duty cycling, it is essential to obtain the probability of each state. In this paper, we analytically derive steady state probability of sensor node states, i.e., sleep, listen, and active states, based on traffic characteristics and timer values, i.e., sleep timer, listen timer, and active timer. The effect of traffic characteristics and timer values on the steady state probability and energy consumption is analyzed in detail. Our work can provide sensor network operators guideline for selecting appropriate timer values for efficient energy conservation. The analytical methodology developed in this paper can be extended to other energy conservation schemes based on duty cycling with different sensor node states, without much difficulty.

10 CFR 431.193 - Test procedures for measuring energy consumption of distribution transformers.

Science.gov (United States)

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Test procedures for measuring energy consumption of distribution transformers. 431.193 Section 431.193 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY... § 431.193 Test procedures for measuring energy consumption of distribution transformers. The test...

A robust H.264/AVC video watermarking scheme with drift compensation.

Science.gov (United States)

Jiang, Xinghao; Sun, Tanfeng; Zhou, Yue; Wang, Wan; Shi, Yun-Qing

2014-01-01

A robust H.264/AVC video watermarking scheme for copyright protection with self-adaptive drift compensation is proposed. In our scheme, motion vector residuals of macroblocks with the smallest partition size are selected to hide copyright information in order to hold visual impact and distortion drift to a minimum. Drift compensation is also implemented to reduce the influence of watermark to the most extent. Besides, discrete cosine transform (DCT) with energy compact property is applied to the motion vector residual group, which can ensure robustness against intentional attacks. According to the experimental results, this scheme gains excellent imperceptibility and low bit-rate increase. Malicious attacks with different quantization parameters (QPs) or motion estimation algorithms can be resisted efficiently, with 80% accuracy on average after lossy compression.

Energy efficiency optimization in distribution transformers considering Spanish distribution regulation policy

Energy Technology Data Exchange (ETDEWEB)

Pezzini, Paola [Centre d' Innovacio en Convertidors Estatics i Accionaments (CITCEA-UPC), E.T.S. Enginyeria Industrial Barcelona, Universitat Politecnica Catalunya, Diagonal, 647, Pl. 2, 08028 Barcelona (Spain); Gomis-Bellmunt, Oriol; Sudria-Andreu, Antoni [Centre d' Innovacio en Convertidors Estatics i Accionaments (CITCEA-UPC), E.T.S. Enginyeria Industrial Barcelona, Universitat Politecnica Catalunya, Diagonal, 647, Pl. 2, 08028 Barcelona (Spain); IREC Catalonia Institute for Energy Research, Josep Pla, B2, Pl. Baixa, 08019 Barcelona (Spain); Frau-Valenti, Joan [ENDESA, Carrer Joan Maragall, 16 07006 Palma (Spain)

2010-12-15

In transmission and distribution systems, the high number of installed transformers, a loss source in networks, suggests a good potential for energy savings. This paper presents how the Spanish Distribution regulation policy, Royal Decree 222/2008, affects the overall energy efficiency in distribution transformers. The objective of a utility is the maximization of the benefit, and in case of failures, to install a chosen transformer in order to maximize the profit. Here, a novel method to optimize energy efficiency, considering the constraints set by the Spanish Distribution regulation policy, is presented; its aim is to achieve the objectives of the utility when installing new transformers. The overall energy efficiency increase is a clear result that can help in meeting the requirements of European environmental plans, such as the '20-20-20' action plan. (author)

An Effective Collaborative Mobile Weighted Clustering Schemes for Energy Balancing in Wireless Sensor Networks.

Science.gov (United States)

Tang, Chengpei; Shokla, Sanesy Kumcr; Modhawar, George; Wang, Qiang

2016-02-19

Collaborative strategies for mobile sensor nodes ensure the efficiency and the robustness of data processing, while limiting the required communication bandwidth. In order to solve the problem of pipeline inspection and oil leakage monitoring, a collaborative weighted mobile sensing scheme is proposed. By adopting a weighted mobile sensing scheme, the adaptive collaborative clustering protocol can realize an even distribution of energy load among the mobile sensor nodes in each round, and make the best use of battery energy. A detailed theoretical analysis and experimental results revealed that the proposed protocol is an energy efficient collaborative strategy such that the sensor nodes can communicate with a fusion center and produce high power gain.

Energy Transformation: Teaching Youth about Energy Efficiency while Meeting Science Essential Standards

Science.gov (United States)

Kirby, Sarah D.; Chilcote, Amy G.

2014-01-01

This article describes the Energy Transformation 4-H school enrichment curriculum. The curriculum addresses energy efficiency and conservation while meeting sixth-grade science essential standards requirements. Through experiential learning, including building and testing a model home, youth learn the relationship between various technologies and…

Adaptive protection scheme

Directory of Open Access Journals (Sweden)

R. Sitharthan

2016-09-01

Full Text Available This paper aims at modelling an electronically coupled distributed energy resource with an adaptive protection scheme. The electronically coupled distributed energy resource is a microgrid framework formed by coupling the renewable energy source electronically. Further, the proposed adaptive protection scheme provides a suitable protection to the microgrid for various fault conditions irrespective of the operating mode of the microgrid: namely, grid connected mode and islanded mode. The outstanding aspect of the developed adaptive protection scheme is that it monitors the microgrid and instantly updates relay fault current according to the variations that occur in the system. The proposed adaptive protection scheme also employs auto reclosures, through which the proposed adaptive protection scheme recovers faster from the fault and thereby increases the consistency of the microgrid. The effectiveness of the proposed adaptive protection is studied through the time domain simulations carried out in the PSCAD⧹EMTDC software environment.

Calculating the binding free energies of charged species based on explicit-solvent simulations employing lattice-sum methods: An accurate correction scheme for electrostatic finite-size effects

Energy Technology Data Exchange (ETDEWEB)

Rocklin, Gabriel J. [Department of Pharmaceutical Chemistry, University of California San Francisco, 1700 4th St., San Francisco, California 94143-2550, USA and Biophysics Graduate Program, University of California San Francisco, 1700 4th St., San Francisco, California 94143-2550 (United States); Mobley, David L. [Departments of Pharmaceutical Sciences and Chemistry, University of California Irvine, 147 Bison Modular, Building 515, Irvine, California 92697-0001, USA and Department of Chemistry, University of New Orleans, 2000 Lakeshore Drive, New Orleans, Louisiana 70148 (United States); Dill, Ken A. [Laufer Center for Physical and Quantitative Biology, 5252 Stony Brook University, Stony Brook, New York 11794-0001 (United States); Hünenberger, Philippe H., E-mail: phil@igc.phys.chem.ethz.ch [Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH, 8093 Zürich (Switzerland)

2013-11-14

-periodic PB calculations for a given system, its dependence on the box size being analytical. The latter scheme also provides insight into the physical origin of the finite-size effects. These two schemes also encompass a correction for discrete solvent effects that persists even in the limit of infinite box sizes. Application of either scheme essentially eliminates the size dependence of the corrected charging free energies (maximal deviation of 1.5 kJ mol{sup −1}). Because it is simple to apply, the analytical correction scheme offers a general solution to the problem of finite-size effects in free-energy calculations involving charged solutes, as encountered in calculations concerning, e.g., protein-ligand binding, biomolecular association, residue mutation, pK{sub a} and redox potential estimation, substrate transformation, solvation, and solvent-solvent partitioning.

Calculating the binding free energies of charged species based on explicit-solvent simulations employing lattice-sum methods: An accurate correction scheme for electrostatic finite-size effects

Science.gov (United States)

Rocklin, Gabriel J.; Mobley, David L.; Dill, Ken A.; Hünenberger, Philippe H.

2013-11-01

calculations for a given system, its dependence on the box size being analytical. The latter scheme also provides insight into the physical origin of the finite-size effects. These two schemes also encompass a correction for discrete solvent effects that persists even in the limit of infinite box sizes. Application of either scheme essentially eliminates the size dependence of the corrected charging free energies (maximal deviation of 1.5 kJ mol-1). Because it is simple to apply, the analytical correction scheme offers a general solution to the problem of finite-size effects in free-energy calculations involving charged solutes, as encountered in calculations concerning, e.g., protein-ligand binding, biomolecular association, residue mutation, pKa and redox potential estimation, substrate transformation, solvation, and solvent-solvent partitioning.

Calculating the binding free energies of charged species based on explicit-solvent simulations employing lattice-sum methods: an accurate correction scheme for electrostatic finite-size effects.

Science.gov (United States)

Rocklin, Gabriel J; Mobley, David L; Dill, Ken A; Hünenberger, Philippe H

2013-11-14

calculations for a given system, its dependence on the box size being analytical. The latter scheme also provides insight into the physical origin of the finite-size effects. These two schemes also encompass a correction for discrete solvent effects that persists even in the limit of infinite box sizes. Application of either scheme essentially eliminates the size dependence of the corrected charging free energies (maximal deviation of 1.5 kJ mol(-1)). Because it is simple to apply, the analytical correction scheme offers a general solution to the problem of finite-size effects in free-energy calculations involving charged solutes, as encountered in calculations concerning, e.g., protein-ligand binding, biomolecular association, residue mutation, pKa and redox potential estimation, substrate transformation, solvation, and solvent-solvent partitioning.

An adaptive short-term prediction scheme for wind energy storage management

International Nuclear Information System (INIS)

Blonbou, Ruddy; Monjoly, Stephanie; Dorville, Jean-Francois

2011-01-01

Research highlights: → We develop a real time algorithm for grid-connected wind energy storage management. → The method aims to guarantee, with ±5% error margin, the power sent to the grid. → Dynamic scheduling of energy storage is based on short-term energy prediction. → Accurate predictions reduce the need in storage capacity. -- Abstract: Efficient forecasting scheme that includes some information on the likelihood of the forecast and based on a better knowledge of the wind variations characteristics along with their influence on power output variation is of key importance for the optimal integration of wind energy in island's power system. In the Guadeloupean archipelago (French West-Indies), with a total wind power capacity of 25 MW; wind energy can represent up to 5% of the instantaneous electricity production. At this level, wind energy contribution can be equivalent to the current network primary control reserve, which causes balancing difficult. The share of wind energy is due to grow even further since the objective is set to reach 118 MW by 2020. It is an absolute evidence for the network operator that due to security concerns of the electrical grid, the share of wind generation should not increase unless solutions are found to solve the prediction problem. The University of French West-Indies and Guyana has developed a short-term wind energy prediction scheme that uses artificial neural networks and adaptive learning procedures based on Bayesian approach and Gaussian approximation. This paper reports the results of the evaluation of the proposed approach; the improvement with respect to the simple persistent prediction model was globally good. A discussion on how such a tool combined with energy storage capacity could help to smooth the wind power variation and improve the wind energy penetration rate into island utility network is also proposed.

Computational scheme for pH-dependent binding free energy calculation with explicit solvent.

Science.gov (United States)

Lee, Juyong; Miller, Benjamin T; Brooks, Bernard R

2016-01-01

We present a computational scheme to compute the pH-dependence of binding free energy with explicit solvent. Despite the importance of pH, the effect of pH has been generally neglected in binding free energy calculations because of a lack of accurate methods to model it. To address this limitation, we use a constant-pH methodology to obtain a true ensemble of multiple protonation states of a titratable system at a given pH and analyze the ensemble using the Bennett acceptance ratio (BAR) method. The constant pH method is based on the combination of enveloping distribution sampling (EDS) with the Hamiltonian replica exchange method (HREM), which yields an accurate semi-grand canonical ensemble of a titratable system. By considering the free energy change of constraining multiple protonation states to a single state or releasing a single protonation state to multiple states, the pH dependent binding free energy profile can be obtained. We perform benchmark simulations of a host-guest system: cucurbit[7]uril (CB[7]) and benzimidazole (BZ). BZ experiences a large pKa shift upon complex formation. The pH-dependent binding free energy profiles of the benchmark system are obtained with three different long-range interaction calculation schemes: a cutoff, the particle mesh Ewald (PME), and the isotropic periodic sum (IPS) method. Our scheme captures the pH-dependent behavior of binding free energy successfully. Absolute binding free energy values obtained with the PME and IPS methods are consistent, while cutoff method results are off by 2 kcal mol(-1) . We also discuss the characteristics of three long-range interaction calculation methods for constant-pH simulations. © 2015 The Protein Society.

Scale transformations, the energy-momentum tensor, and the equation of state

International Nuclear Information System (INIS)

Carruthers, P.

1989-01-01

The Equation of State (EOS) relates diagonal elements of the energy-momentum tensor θ μν . The first moment of the energy-momentum tensor generates scale transformations. The virial theorem, a consequence of the behavior of the energy density under scale transformations, allows one to eliminate the kinetic energy in terms of the potential terms. The trace theorem for the energy-momentum tensor expresses ε-3p in terms of ensemble averages of scale-breaking operators, allowing a new approach to the EOS. 10 refs

High Energy Density Physics and Exotic Acceleration Schemes

International Nuclear Information System (INIS)

Cowan, T.; Colby, E.

2005-01-01

The High Energy Density and Exotic Acceleration working group took as our goal to reach beyond the community of plasma accelerator research with its applications to high energy physics, to promote exchange with other disciplines which are challenged by related and demanding beam physics issues. The scope of the group was to cover particle acceleration and beam transport that, unlike other groups at AAC, are not mediated by plasmas or by electromagnetic structures. At this Workshop, we saw an impressive advancement from years past in the area of Vacuum Acceleration, for example with the LEAP experiment at Stanford. And we saw an influx of exciting new beam physics topics involving particle propagation inside of solid-density plasmas or at extremely high charge density, particularly in the areas of laser acceleration of ions, and extreme beams for fusion energy research, including Heavy-ion Inertial Fusion beam physics. One example of the importance and extreme nature of beam physics in HED research is the requirement in the Fast Ignitor scheme of inertial fusion to heat a compressed DT fusion pellet to keV temperatures by injection of laser-driven electron or ion beams of giga-Amp current. Even in modest experiments presently being performed on the laser-acceleration of ions from solids, mega-amp currents of MeV electrons must be transported through solid foils, requiring almost complete return current neutralization, and giving rise to a wide variety of beam-plasma instabilities. As keynote talks our group promoted Ion Acceleration (plenary talk by A. MacKinnon), which historically has grown out of inertial fusion research, and HIF Accelerator Research (invited talk by A. Friedman), which will require impressive advancements in space-charge-limited ion beam physics and in understanding the generation and transport of neutralized ion beams. A unifying aspect of High Energy Density applications was the physics of particle beams inside of solids, which is proving to

New organization scheme for the energy supply in the not interconnected zones of Colombia

International Nuclear Information System (INIS)

Zapata, Josue; Bayona Lugdy

2001-01-01

The paper shows a new scheme of solutions in the financial institutional environment and regulatory, in this sense it thinks about the creation from a support unit to the rural energy administration that takes charge of to identify energy solutions and the technical and organizational support of the service of a foundation that manage the obtained resources and a interconnected scheme to the current conditions of the NIZ. In Colombia the not interconnected zones NIZ corresponds those of the country that don't receive electric power service through the national interconnected system, and who interconnection is not economically feasible

Resonant transformation of electrostatic energy in ExB field system

International Nuclear Information System (INIS)

Tanizuka, Noboru

1986-01-01

A theoretical consideration on an effective transformation of electrostatic potential energy is given. A transformator particle is introduced with the transformation in an ExB field system. A device constant of the system is introduced comparing with some empirical, practical examples and an experimental proof of the transformation is given. Finally a nuclear fusion device plan is proposed based on the idea of the consideration. (author)

Energy efficient power electronic controller for a capacitor-run single-phase induction motor

International Nuclear Information System (INIS)

Saravana Ilango, G.; Samidurai, K.; Roykumar, M.; Thanushkodi, K.

2009-01-01

At present the speed control of a capacitor-run single-phase induction motor is being achieved by using triac based voltage regulators. This paper proposes a new scheme; an electronic transformer acts as a voltage regulator. Performance comparison is made between these two schemes in this paper. It is found that the proposed scheme has superior operating and performance characteristics. Experimental results show that apart from improvement in performance with respect to power factor and total harmonic distortion an appreciable amount of energy saving is also obtained in the electronic transformer based scheme.

Bridging the industrial energy efficiency gap – Assessing the evidence from the Italian white certificate scheme

International Nuclear Information System (INIS)

Stede, Jan

2017-01-01

The Italian white certificate scheme is the main national policy instrument to incentivise energy efficiency of the industrial sector, with savings from white certificates amounting to 2% of Italy's 2012 primary energy consumption. The mechanism sets binding energy-saving targets on electricity and gas distributors with at least 50,000 clients and includes a voluntary opt-in model for participation from other parties. This paper investigates and assesses the elements of the scheme that help overcome several barriers to deliver industrial energy efficiency. Results from a survey conducted among leading experts indicate that the Italian system provides a strong financial incentive to energy efficiency investments, covering a significant share of investment costs and thus reducing payback time. Moreover, the scheme fosters the development of energy service companies (ESCOs), which are key to developing, installing and arranging finance for projects on the ground. In conjunction with other policies, the mechanism also raises awareness of energy efficiency investment opportunities, thus helping overcome the market failure of insufficient information. Core challenges remain, including tackling regulatory uncertainty and improving access to finance. - Highlights: • Due to a strong monetary incentive, energy savings are mainly achieved in industry. • White certificates cover around 25 per cent of investment costs in Italian industry. • Active energy services sector with >100 energy service companies built from scratch. • Tackling regulatory uncertainty is the key challenge.

A Non-blind Color Image Watermarking Scheme Resistent Against Geometric Attacks

Directory of Open Access Journals (Sweden)

A. Ghafoor

2012-12-01

Full Text Available A non-blind color image watermarking scheme using principle component analysis, discrete wavelet transform and singular value decomposition is proposed. The color components are uncorrelated using principle component analysis. The watermark is embedded into the singular values of discrete wavelet transformed sub-band associated with principle component containing most of the color information. The scheme was tested against various attacks (including histogram equalization, rotation, Gaussian noise, scaling, cropping, Y-shearing, X-shearing, median filtering, affine transformation, translation, salt & pepper, sharpening, to check robustness. The results of proposed scheme are compared with state-of-the-art existing color watermarking schemes using normalized correlation coefficient and peak signal to noise ratio. The simulation results show that proposed scheme is robust and imperceptible.

Energy-Efficient Broadcasting Scheme for Smart Industrial Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Zhuangbin Chen

2017-01-01

Full Text Available In smart Industrial Wireless Sensor Networks (IWSNs, sensor nodes usually adopt a programmable technology. These smart devices can obtain new or special functions by reprogramming: they upgrade their soft systems through receiving new version of program codes. If sensor nodes need to be upgraded, the sink node will propagate program code packets to them through “one-to-many” broadcasting, and therefore new capabilities can be obtained, forming the so-called Software Defined Network (SDN. However, due to the high volume of code packet, the constraint energy of sensor node, and the unreliable link quality of wireless network, rapidly broadcasting the code packets to all nodes in network can be a challenge issue. In this paper, a novel Energy-efficient Broadcast scheme with adjustable broadcasting radius is proposed aiming to improve the performance of network upgrade. In our scheme, the nonhotspots sensor nodes take full advantage of their residual energy caused in data collection period to improve the packet reception probability and reduce the broadcasting delay of code packet transmission by enlarging the broadcasting radius, that is, the transmitting power. The theoretical analyses and experimental results show that, compared with previous work, our approach can averagely reduce the Network Upgrade Delay (NUD by 14.8%–45.2% and simultaneously increase the reliability without harming the lifetime of network.

Delivering energy efficiency and carbon reduction schemes in England: Lessons from Green Deal Pioneer Places

International Nuclear Information System (INIS)

Marchand, Robert D.; Koh, S.C. Lenny; Morris, Jonathan C.

2015-01-01

Against a background of growing international and national carbon reduction legislation, the UK government introduced the “Green Deal” to deliver a significant increase in housing energy efficiency and reduction in carbon emissions. This paper reflects on one English local authority's experience delivering a programme intended to foster local interest in the Green Deal. Drawing on social surveys and pre and post Green Deal intervention interviews with five demonstrator homes (households that applied to receive a Green Deal package fully funded by the scheme, providing a test bed for the Green Deal recruitment and installation process), this paper shows that awareness and understanding of the Green Deal scheme is low. There is opposition to the cost of finance offered but a strong interest in improving household warmth and for funding improvements through payments added to the electricity bill. Demonstrator home residents perceived Green Deals had improved the warmth and quality of their home, but saving money was the primary motivator for their involvement, not increasing warmth. Whilst Green Deal has not delivered the level of success that was hoped, much can be learned from the scheme to improve future energy efficiency schemes that will be necessary to deliver emission reduction commitments. -- Highlights: •Resident awareness and understanding of the Green Deal is low. •Green Deal assessment costs and loan interest rates are biggest barriers to uptake. •Funding energy improvements via a charge on electricity bill welcomed by residents. •Saving money rather than increasing warmth main motivator for scheme involvement. •Insights from this work should be used to inform future emission reduction schemes

Leading global energy and environmental transformation: Unified ASEAN biomass-based bio-energy system incorporating the clean development mechanism

International Nuclear Information System (INIS)

Lim, Steven; Lee, Keat Teong

2011-01-01

In recent years, the ten member countries in the Association of Southeast Asia Nations (ASEAN) have experienced high economic growth and, in tandem, a substantial increment in energy usage and demand. Consequently, they are now under intense pressure to secure reliable energy supplies to keep up with their growth rate. Fossil fuels remain the primary source of energy for the ASEAN countries, due to economic and physical considerations. This situation has led to unrestrained emissions of greenhouse gases to the environment and thus effectively contributes to global climate change. The abundant supply of biomass from their tropical environmental conditions offers great potential for ASEAN countries to achieve self-reliance in energy supplies. This fact can simultaneously transform into the main driving force behind combating global climate change, which is associated with the usage of fossil fuels. This research article explores the potential and advantages for ASEAN investment in biomass-based bio-energy supply, processing and distribution network with an emphasis on regional collaborations. It also investigates the implementation and operational challenges in terms of political, economic and technical factors for the cross-border energy scheme. Reliance of ASEAN countries on the clean development mechanism (CDM) to address most of the impediments in developing the project is also under scrutiny. Unified co-operation among ASEAN countries in integrating biomass-based bio-energy systems and utilising the clean development mechanism (CDM) as the common effort could serve as the prime example for regional partnerships in achieving sustainable development for the energy and environmental sector in the future. -- Highlights: →A study that explores feasibility for ASEAN investment in biomass-based bio-energy. →Focus is given on regional supply, processing and distribution network. →Cross-border implementation and operational challenges are discussed thoroughly.

Digital Image Watermarking in Transform Domains

International Nuclear Information System (INIS)

EL-Shazly, E.H.M.

2012-01-01

Fast development of internet and availability of huge digital content make it easy to create, modify and copy digital media such as audio, video and images. This causes a problem for owners of that content and hence a need to copy right protection tool was essential. First, encryption was proposed but it ensures protection during transmission only and once decryption occurred any one can modify the data. at that point watermarking was introduced as a solution to such problem. Watermarking is a process of inserting a low energy signal in to a high energy one so that it doesn't affect the main signal features. A good digital image watermarking technique should satisfy four requirements: 1) Embedding of a watermark should not degrade the host image visual quality (imperceptibility). 2) The embedded watermark should stick to the host image so that it couldn’t be removed by common image processing operation and could be extracted from the attacked watermarked image (robustness). 3) Knowing the embedding and extraction procedures is sufficient but not enough to extract the watermark; extra keys should be needed (security). 4) The watermarking technique should allow embedding and extraction of more than one watermark each independent of the other (capacity). This thesis presents a watermarking scheme that full fill the mentioned four requirements by jointing transform domains with Fractional Fourier Transform Domain (FracFT). More work on cascaded Discrete Wavelet Transform DWT with FracFT was done to develop a joint transform simply called Fractional Wavelet Transform (FWT). The proposed schemes were tested with different image processing attacks to verify its robustness. Finally, the watermarked image is transmitted over simulated MC CDMA channel to prove robustness in real transmission conditions case.

Stable schemes for dissipative particle dynamics with conserved energy

Energy Technology Data Exchange (ETDEWEB)

Stoltz, Gabriel, E-mail: stoltz@cermics.enpc.fr

2017-07-01

This article presents a new numerical scheme for the discretization of dissipative particle dynamics with conserved energy. The key idea is to reduce elementary pairwise stochastic dynamics (either fluctuation/dissipation or thermal conduction) to effective single-variable dynamics, and to approximate the solution of these dynamics with one step of a Metropolis–Hastings algorithm. This ensures by construction that no negative internal energies are encountered during the simulation, and hence allows to increase the admissible timesteps to integrate the dynamics, even for systems with small heat capacities. Stability is only limited by the Hamiltonian part of the dynamics, which suggests resorting to multiple timestep strategies where the stochastic part is integrated less frequently than the Hamiltonian one.

A Robust H.264/AVC Video Watermarking Scheme with Drift Compensation

Directory of Open Access Journals (Sweden)

Xinghao Jiang

2014-01-01

Full Text Available A robust H.264/AVC video watermarking scheme for copyright protection with self-adaptive drift compensation is proposed. In our scheme, motion vector residuals of macroblocks with the smallest partition size are selected to hide copyright information in order to hold visual impact and distortion drift to a minimum. Drift compensation is also implemented to reduce the influence of watermark to the most extent. Besides, discrete cosine transform (DCT with energy compact property is applied to the motion vector residual group, which can ensure robustness against intentional attacks. According to the experimental results, this scheme gains excellent imperceptibility and low bit-rate increase. Malicious attacks with different quantization parameters (QPs or motion estimation algorithms can be resisted efficiently, with 80% accuracy on average after lossy compression.

On the properties of energy stable flux reconstruction schemes for implicit large eddy simulation

Science.gov (United States)

Vermeire, B. C.; Vincent, P. E.

2016-12-01

We begin by investigating the stability, order of accuracy, and dispersion and dissipation characteristics of the extended range of energy stable flux reconstruction (E-ESFR) schemes in the context of implicit large eddy simulation (ILES). We proceed to demonstrate that subsets of the E-ESFR schemes are more stable than collocation nodal discontinuous Galerkin methods recovered with the flux reconstruction approach (FRDG) for marginally-resolved ILES simulations of the Taylor-Green vortex. These schemes are shown to have reduced dissipation and dispersion errors relative to FRDG schemes of the same polynomial degree and, simultaneously, have increased Courant-Friedrichs-Lewy (CFL) limits. Finally, we simulate turbulent flow over an SD7003 aerofoil using two of the most stable E-ESFR schemes identified by the aforementioned Taylor-Green vortex experiments. Results demonstrate that subsets of E-ESFR schemes appear more stable than the commonly used FRDG method, have increased CFL limits, and are suitable for ILES of complex turbulent flows on unstructured grids.

Energy and Quality-Aware Multimedia Signal Processing

Science.gov (United States)

Emre, Yunus

Today's mobile devices have to support computation-intensive multimedia applications with a limited energy budget. In this dissertation, we present architecture level and algorithm-level techniques that reduce energy consumption of these devices with minimal impact on system quality. First, we present novel techniques to mitigate the effects of SRAM memory failures in JPEG2000 implementations operating in scaled voltages. We investigate error control coding schemes and propose an unequal error protection scheme tailored for JPEG2000 that reduces overhead without affecting the performance. Furthermore, we propose algorithm-specific techniques for error compensation that exploit the fact that in JPEG2000 the discrete wavelet transform outputs have larger values for low frequency subband coefficients and smaller values for high frequency subband coefficients. Next, we present use of voltage overscaling to reduce the data-path power consumption of JPEG codecs. We propose an algorithm-specific technique which exploits the characteristics of the quantized coefficients after zig-zag scan to mitigate errors introduced by aggressive voltage scaling. Third, we investigate the effect of reducing dynamic range for datapath energy reduction. We analyze the effect of truncation error and propose a scheme that estimates the mean value of the truncation error during the pre-computation stage and compensates for this error. Such a scheme is very effective for reducing the noise power in applications that are dominated by additions and multiplications such as FIR filter and transform computation. We also present a novel sum of absolute difference (SAD) scheme that is based on most significant bit truncation. The proposed scheme exploits the fact that most of the absolute difference (AD) calculations result in small values, and most of the large AD values do not contribute to the SAD values of the blocks that are selected. Such a scheme is highly effective in reducing the energy

Transformation research for a sustainable energy system. Contributions; Transformationsforschung fuer ein nachhaltiges Energiesystem. Beitraege

Energy Technology Data Exchange (ETDEWEB)

Stadermann, Gerd; Szczepanski, Petra; Wunschick, Franziska; Martin, Niklas (comps.)

2012-03-15

Within the 2011 annual meeting of the Renewable Energy Research Association (Berlin, Federal Republic of Germany) from 12th to 13th October 2011, the following lectures were held: (1) Environmentally safe and socially compatible transformation of energy systems (G. Schuette); (2) Open questions on the transformation of energy systems (E. Weber); (3) System analysis on the transformation of energy systems up to 2050 (J. Schmid); (4) Economic aspects: Chances, markets and workplaces (F. Staiss); (5) Perspectives for an interplay of energy efficiency and renewable energy resources as well as their implementation in the energy system (A. Bett); (6) New accents of research promotion for a more rapid development of renewable energy sources (K. Deller); (7) The 6th Energy Research Program of the Federal Government (R. Tryfonidou); (8) Recommendations of the FVEE for the research policy of the Research Government (G. Sadermann); (9) How can research and politics promote the system transformation (M. Hustedt); (10) The energy system of tomorrow - Strategies and research for the transformation of high amounts of renewable energy resources (W. Duerrschmidt); (11) Long-term strategies for the development of renewable energies in Germany (J. Nitsch); (12) Development of storage capacities for an efficient power generation by renewable energy resources in Germany and Europe by 2050 (Y. Scholz); (13) Prognoses of temporal and spatial variability of renewable energy resources (B. Lange); (14) Smart Grids - Transformation of our electrical energy supply (G. Ebert); (15) Model regions for intelligently networked energy systems; (16) Cities and concepts of neighbourhood - model cities (D. Schmidt); (17) Transformation of the German power system to a decentral regenerative economy (U. Leprich); (18) Alteration of the general conditions for new incentive models, heat acts, restoration of buildings (M. Schmidt); (19) Acceptance and participation research on energy sustainability (P

Saving energy and money at choice of power transformers, v. 16(63)

International Nuclear Information System (INIS)

Jankoski, Dimitar

2008-01-01

When power transformers work at regular conditions, besides they exert theirs principal function, they constantly spend electrical energy that is, always work with losses. Depending od performances, sometimes those losses can be drastically different, although the transformers can equal power and some voltages of transformation. Considering that the loss of energy has its own price, a dilemma whether it is better economic reason to purchase new expensive transformer with smaller losses or one cheaper with more losses during its work-comes out. This paper analysis such case. The presented access can usefully serve in practice, in making the right decision in replacing the old transformer with the new one, or choosing the new transformer. (Author)

Saving energy and money at choice of power transformers, v. 16(62)

International Nuclear Information System (INIS)

Jankoski, Dimitar

2008-01-01

When power transformers work at regular conditions, besides they exert theirs principal function, they constantly spend electrical energy that is, always work with losses. Depending od performances, sometimes those losses can be drastically different, although the transformers can equal power and some voltages of transformation. Considering that the loss of energy has its own price, a dilemma whether it is better economic reason to purchase new expensive transformer with smaller losses or one cheaper with more losses during its work-comes out. This paper analysis such case. The presented access can usefully serve in practice, in making the right decision in replacing the old transformer with the new one, or choosing the new transformer. (Author)

Implementation of the EU directive on the energy performance of buildings: Development of the Latvian Scheme for energy auditing of buildings and inspection of boilers. Project document

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

'Development of the Latvian Scheme for energy auditing of buildings and inspection of boilers' includes major steps in implementing the EU EPB directive in Latvia. The EPB directive includes a number of efforts: 1. A methodology for calculation of the integrated energy performance of buildings 2. Application of minimum requirements on the energy performance for new buildings 3. Application of minimum requirements on the energy performance for larger existing buildings subject to major renovation 4. Energy performance certification (energy labelling) of buildings 5. Regular inspection of boilers and of air-conditioning systems in buildings, and assessment of heating installations in older systems. The present project includes activities connected to point 4 and point 5. The results will include 4 steps in implementing the EU EPB directive: 1) A Latvian training of certified independent energy auditors to be active conducting energy audits and issuing energy performance certificates. Including a handbook in energy auditing. 2) A Latvian training of certified independent experts for inspection of boilers, air-con systems and assessing older heating systems. Including a handbook in boiler inspection. 3) A proposal for the institutional set-up for a connected scheme for energy auditing and a scheme for boiler inspection 4) Initial information on the scheme of energy auditors and of the boiler inspection. (au)

Transforming Global Markets for Clean Energy Products

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

This paper looks at three clean energy product categories: equipment energy efficiency; low-carbon transport, including high-efficiency vehicles and electric/plug-in hybrid electric vehicles (EV/PHEVs); and solar photovoltaic (PV) power. Each section identifies ways to enhance global co-operation among major economies through case studies and examples, and ends with specific suggestions for greater international collaboration on market transformation efforts. An annex with more detailed case studies on energy-efficient electric motors, televisions, external power supplies and compact fluorescent lights is included in the paper.

Total energy and potential enstrophy conserving schemes for the shallow water equations using Hamiltonian methods - Part 1: Derivation and properties

Science.gov (United States)

Eldred, Christopher; Randall, David

2017-02-01

The shallow water equations provide a useful analogue of the fully compressible Euler equations since they have similar characteristics: conservation laws, inertia-gravity and Rossby waves, and a (quasi-) balanced state. In order to obtain realistic simulation results, it is desirable that numerical models have discrete analogues of these properties. Two prototypical examples of such schemes are the 1981 Arakawa and Lamb (AL81) C-grid total energy and potential enstrophy conserving scheme, and the 2007 Salmon (S07) Z-grid total energy and potential enstrophy conserving scheme. Unfortunately, the AL81 scheme is restricted to logically square, orthogonal grids, and the S07 scheme is restricted to uniform square grids. The current work extends the AL81 scheme to arbitrary non-orthogonal polygonal grids and the S07 scheme to arbitrary orthogonal spherical polygonal grids in a manner that allows for both total energy and potential enstrophy conservation, by combining Hamiltonian methods (work done by Salmon, Gassmann, Dubos, and others) and discrete exterior calculus (Thuburn, Cotter, Dubos, Ringler, Skamarock, Klemp, and others). Detailed results of the schemes applied to standard test cases are deferred to part 2 of this series of papers.

Impacts of Interface Energies and Transformation Strain from BCC to FCC on Massive-like δ-γ Transformation in Steel

International Nuclear Information System (INIS)

Yoshiya, M; Sato, M; Watanabe, M; Nakajima, K; Yokoi, T; Ueshima, N; Nagira, T; Yasuda, H

2015-01-01

Interface energies of δ/γ, γ/γ, δ/δ, L/δ, and L/γ interfaces, at first, as a function of misorientation were evaluated with an aid of atomistic simulations with embedded atom method. Then, under geometric constraints where grains or interfaces compete each other to minimize overall free energy, effective interface energies for those interfaces were quantified. It is found that neither the minimum nor effective δ/γ interface energies, 0.41 or 0.56 J/m 2 , respectively, is significantly higher than those of other interfaces including liquid/solid interfaces, but the δ/γ interface energy is significantly high for the small entropy change upon δ-γ massive-like transformation, resulting in significantly higher undercooling required for γ nucleation in the δ phase matrix than in solidification. Detachment of δ-phase dendrite tips away from γ-phase dendrite trunks can be explained only from a viewpoint of interface energy if small misorientationis introduced at the δ/γ interface from the perfect lattice matching between BCC and FCC crystal structures. Examining the BCC-to-FCC transformation strain on the γ nucleation in the massive-like transformation, the γ nucleation is prohibited 170 K or more undercooling is achieved unless any relaxation mechanism for the transformation strain is taken into account. (paper)

An Optimization Scheme for Water Pump Control in Smart Fish Farm with Efficient Energy Consumption

Directory of Open Access Journals (Sweden)

Israr Ullah

2018-06-01

Full Text Available Healthy fish production requires intensive care and ensuring stable and healthy production environment inside the farm tank is a challenging task. An Internet of Things (IoT based automated system is highly desirable that can continuously monitor the fish tanks with optimal resources utilization. Significant cost reduction can be achieved if farm equipment and water pumps are operated only when required using optimization schemes. In this paper, we present a general system design for smart fish farms. We have developed an optimization scheme for water pump control to maintain desired water level in fish tank with efficient energy consumption through appropriate selection of pumping flow rate and tank filling level. Proposed optimization scheme attempts to achieve a trade-off between pumping duration and flow rate through selection of optimized water level. Kalman filter algorithm is applied to remove error in sensor readings. We observed through simulation results that optimization scheme achieve significant reduction in energy consumption as compared to the two alternate schemes, i.e., pumping with maximum and minimum flow rates. Proposed system can help in collecting the data about the farm for long-term analysis and better decision making in future for efficient resource utilization and overall profit maximization.

Girsanov's transformation based variance reduced Monte Carlo simulation schemes for reliability estimation in nonlinear stochastic dynamics

Science.gov (United States)

Kanjilal, Oindrila; Manohar, C. S.

2017-07-01

The study considers the problem of simulation based time variant reliability analysis of nonlinear randomly excited dynamical systems. Attention is focused on importance sampling strategies based on the application of Girsanov's transformation method. Controls which minimize the distance function, as in the first order reliability method (FORM), are shown to minimize a bound on the sampling variance of the estimator for the probability of failure. Two schemes based on the application of calculus of variations for selecting control signals are proposed: the first obtains the control force as the solution of a two-point nonlinear boundary value problem, and, the second explores the application of the Volterra series in characterizing the controls. The relative merits of these schemes, vis-à-vis the method based on ideas from the FORM, are discussed. Illustrative examples, involving archetypal single degree of freedom (dof) nonlinear oscillators, and a multi-degree of freedom nonlinear dynamical system, are presented. The credentials of the proposed procedures are established by comparing the solutions with pertinent results from direct Monte Carlo simulations.

Energy Stability Analysis of Some Fully Discrete Numerical Schemes for Incompressible Navier–Stokes Equations on Staggered Grids

KAUST Repository

Chen, Huangxin; Sun, Shuyu; Zhang, Tao

2017-01-01

In this paper we consider the energy stability estimates for some fully discrete schemes which both consider time and spatial discretizations for the incompressible Navier–Stokes equations. We focus on three kinds of fully discrete schemes, i

Analysis of energy efficiency retrofit schemes for heating, ventilating and air-conditioning systems in existing office buildings based on the modified bin method

International Nuclear Information System (INIS)

Wang, Zhaoxia; Ding, Yan; Geng, Geng; Zhu, Neng

2014-01-01

Highlights: • A modified bin method is adopted to propose and optimize the EER schemes. • A case study is presented to demonstrate the analysis procedures of EER schemes. • Pertinent EER schemes for HVAC systems are proposed for the object building. - Abstract: Poor thermal performance of building envelop and low efficiencies of heating, ventilating and air-conditioning (HVAC) systems can always be found in the existing office buildings with large energy consumption. This paper adopted a modified bin method to propose and optimize the energy efficiency retrofit (EER) schemes. An existing office building in Tianjin was selected as an example to demonstrate the procedures of formulating the design scheme. Pertinent retrofit schemes for HVAC system were proposed after the retrofit of building envelop. With comprehensive consideration of energy efficiency and economic benefits, the recommended scheme that could improve the overall energy efficiency by 71.20% was determined

A self-optimizing scheme for energy balanced routing in Wireless Sensor Networks using SensorAnt.

Science.gov (United States)

Shamsan Saleh, Ahmed M; Ali, Borhanuddin Mohd; Rasid, Mohd Fadlee A; Ismail, Alyani

2012-01-01

Planning of energy-efficient protocols is critical for Wireless Sensor Networks (WSNs) because of the constraints on the sensor nodes' energy. The routing protocol should be able to provide uniform power dissipation during transmission to the sink node. In this paper, we present a self-optimization scheme for WSNs which is able to utilize and optimize the sensor nodes' resources, especially the batteries, to achieve balanced energy consumption across all sensor nodes. This method is based on the Ant Colony Optimization (ACO) metaheuristic which is adopted to enhance the paths with the best quality function. The assessment of this function depends on multi-criteria metrics such as the minimum residual battery power, hop count and average energy of both route and network. This method also distributes the traffic load of sensor nodes throughout the WSN leading to reduced energy usage, extended network life time and reduced packet loss. Simulation results show that our scheme performs much better than the Energy Efficient Ant-Based Routing (EEABR) in terms of energy consumption, balancing and efficiency.

A novel scheme for making cheap electricity with nuclear energy

International Nuclear Information System (INIS)

Pettibone, J.S.

1991-04-01

Nuclear fuels should produce cheaper electricity than coal, considering their high specific energy and low cost. To exploit these properties, the scheme proposed here replaces the expensive reactor/steam-turbine system with an engine in which the expansion of a gas heated by a nuclear explosion raises a mass of liquid, thereby producing stored hydraulic energy. This energy could be converted to electricity by hydroelectric generation with water as the working fluid or by magnetohydrodynamic (MHD) generation with molten metal. A rough cost analysis suggests the hydroelectric system could reduce the present cost of electricity by two-thirds, and the MHD system by even more. Such cheap power would make feasible large-scale electrolysis to produce hydrogen and other fuels and chemical raw materials. 2 refs., 1 fig

Local Content Requirements in Renewable Energy Schemes - Government Procurement or a Violation of International Obligations?

NARCIS (Netherlands)

Verburg, Cornelis

2017-01-01

Numerous States have adopted renewable energy schemes aimed at incentivising investments in renewable energy generation capacity that contain local content requirements as an eligibility criterion to obtain support, such as a feed-in tariff. However, these requirements may violate the international

A New Energy-Efficient Data Transmission Scheme Based on DSC and Virtual MIMO for Wireless Sensor Network

OpenAIRE

Li, Na; Zhang, Liwen; Li, Bing

2015-01-01

Energy efficiency in wireless sensor network (WSN) is one of the primary performance parameters. For improving the energy efficiency of WSN, we introduce distributed source coding (DSC) and virtual multiple-input multiple-output (MIMO) into wireless sensor network and then propose a new data transmission scheme called DSC-MIMO. DSC-MIMO compresses the source data using distributed source coding before transmitting, which is different from the existing communication schemes. Data compression c...

Increasing the transformer ratio at the Argonne wakefield accelerator

International Nuclear Information System (INIS)

Power, J.G.; Conde, M.; Liu, W.; Yusof, Z.; Gai, W.; Jing, C.; Kanareykin, A.

2011-01-01

The transformer ratio is defined as the ratio of the maximum energy gain of the witness bunch to the maximum energy loss experienced by the drive bunch (or a bunch within a multidrive bunch train). This plays an important role in the collinear wakefield acceleration scheme. A high transformer ratio is desirable since it leads to a higher overall efficiency under similar conditions (e.g. the same beam loading, the same structure, etc.). One technique to enhance the transformer ratio beyond the ordinary limit of 2 is to use a ramped bunch train. The first experimental demonstration observed a transformer ratio only marginally above 2 due to the mismatch between the drive microbunch length and the frequency of the accelerating structure (C. Jing, A. Kanareykin, J. Power, M. Conde, Z. Yusof, P. Schoessow, and W. Gai, Phys. Rev. Lett. 98, 144801 (2007)). Recently, we revisited this experiment with an optimized microbunch length using a UV laser stacking technique at the Argonne Wakefield Accelerator facility and measured a transformer ratio of 3.4. Measurements and data analysis from these experiments are presented in detail.

The economics of energy market transformation programs

International Nuclear Information System (INIS)

Duke, R.; Kammen, D.M.

1999-01-01

This paper evaluates three energy-sector market transformation programs: the US Environmental Protection Agency's Green Lights program to promote on-grid efficient lighting; the World Bank Group's new Photovoltaic Market Transformation Initiative; and the federal grain ethanol subsidy. The authors develop a benefit-cost model that uses experience curves to estimate unit cost reductions as a function of cumulative production. Accounting for dynamic feedback between the demand response and price reductions from production experience raises the benefit-cost ratio (BCR) of the first two programs substantially. The BCR of the ethanol program, however, is approximately zero, illustrating a technology for which subsidization was not justified. Their results support a broader role for market transformation programs to commercialize new environmentally attractive technologies, but the ethanol experience suggests moderately funding a broad portfolio composed of technologies that meet strict selection criteria

Hierarchical predictive control scheme for distributed energy storage integrated with residential demand and photovoltaic generation

NARCIS (Netherlands)

Lampropoulos, I.; Garoufalis, P.; van den Bosch, P.P.J.; Kling, W.L.

2015-01-01

A hierarchical control scheme is defined for the energy management of a battery energy storage system which is integrated in a low-voltage distribution grid with residential customers and photovoltaic installations. The scope is the economic optimisation of the integrated system by employing

Linking renewable energy CDM projects and TGC schemes: An analysis of different options

International Nuclear Information System (INIS)

Del Rio, Pablo

2006-01-01

Renewable energy CDM (RE-CDM) projects encourage cost-effective GHG mitigation and enhanced sustainable development opportunities for the host countries. CERs from CDM projects include the value of the former benefits (i.e., 'climate change benefits'), whereas the second can be given value through the issuing and trading of tradable green certificates (TGCs). Countries could agree to trade these TGCs, leading to additional revenues for the investors in renewable energy projects and, therefore, further encouraging the deployment of CDM projects, currently facing significant barriers. However, the design of a combination of CDM projects and TGC schemes raises several conflicting issues and leads to trade-offs. This paper analyses these issues, identifies the alternatives that may exist to link TGC schemes with RE-CDM projects and analyses the impacts of those options on different variables and actors

Linking renewable energy CDM projects and TGC schemes: An analysis of different options

Energy Technology Data Exchange (ETDEWEB)

Del Rio, Pablo [Department of Economics and Business, Facultad de Ciencias Juridicas y Sociales, Universidad de Castilla-La Mancha, C/ Cobertizo de S. Pedro Martir s/n., Toledo-45071 (Spain)]. E-mail: pablo.rio@uclm.es

2006-11-15

Renewable energy CDM (RE-CDM) projects encourage cost-effective GHG mitigation and enhanced sustainable development opportunities for the host countries. CERs from CDM projects include the value of the former benefits (i.e., 'climate change benefits'), whereas the second can be given value through the issuing and trading of tradable green certificates (TGCs). Countries could agree to trade these TGCs, leading to additional revenues for the investors in renewable energy projects and, therefore, further encouraging the deployment of CDM projects, currently facing significant barriers. However, the design of a combination of CDM projects and TGC schemes raises several conflicting issues and leads to trade-offs. This paper analyses these issues, identifies the alternatives that may exist to link TGC schemes with RE-CDM projects and analyses the impacts of those options on different variables and actors.

Acceptance of renewable energies on the grid. RTE is being mobilised. Regional schemes, status on the 31 March 2014

International Nuclear Information System (INIS)

2014-01-01

This document first presents the regulatory framework of the French regional schemes on climate, air and energy (SRCAE) and of the regional schemes of connection to the grid of renewable energies (S3REnR), and briefly indicates their content, their elaboration and implementation process. A map indicates the current situation or status of these SRCAEs and S3REnRs in the different regions (elaboration in progress, approved and published, or registered). It presents the situation before the introduction of these regional schemes, proposes a brief overview of SRCAE objectives by 2020 for photovoltaic and wind energy, indicates some aspects of RTE commitment for the specific case of renewable energies (projected installed power, funding), briefly presents the status of the S3REnR in Auvergne and in Picardie

Markets for energy efficiency: Exploring the implications of an EU-wide 'Tradable White Certificate' scheme

International Nuclear Information System (INIS)

Mundaca, Luis

2008-01-01

Recent developments in European energy policy reveal an increasing interest in implementing the so-called 'Tradable White Certificate' (TWC) schemes to improve energy efficiency. Based on three evaluation criteria (cost-effectiveness, environmental effectiveness and distributional equity) this paper analyses the implications of implementing a European-wide TWC scheme targeting the household and commercial sectors. Using a bottom-up model, quantitative results show significant cost-effective potentials for improvements (ca. 1400 TWh in cumulative energy savings by 2020), with the household sector, gas and space heating representing most of the TWC supply in terms of eligible sector, fuel and energy service demand, respectively. If a single market price of negative externalities is considered, a societal cost-effective potential of energy savings above 30% (compared to the baseline) is observed. In environmental terms, the resulting greenhouse gas emission reductions are around 200 Mt CO 2-eq by 2010, representing nearly 60% of the EU-Kyoto-target. From the qualitative perspective, several embedded ancillary benefits are identified (e.g. employment generation, improved comfort level, reduced 'fuel poverty', security of energy supply). Whereas an EU-wide TWC increases liquidity and reduces the risks of market power, autarky compliance strategies may be expected in order to capture co-benefits nationally. Cross subsidies could occur due to investment recovery mechanisms and there is a risk that effects may be regressive for low-income households. Assumptions undertaken by the modelling approach strongly indicate that high effectiveness of other policy instruments is needed for an EU-wide TWC scheme to be cost-effective

The impact of domestic energy efficiency retrofit schemes on householder attitudes and behaviours

NARCIS (Netherlands)

Long, T.B.; Young, W.; Webber, P.; Gouldson, A.; Harwatt, H.

2015-01-01

Retrofitting existing housing stock to improve energy efficiency is often required to meet climate mitigation, public health and fuel poverty targets. Increasing uptake and effectiveness of retrofit schemes requires understanding of their impacts on householder attitudes and behaviours. This paper

A Fingerprint Encryption Scheme Based on Irreversible Function and Secure Authentication

Directory of Open Access Journals (Sweden)

Yijun Yang

2015-01-01

Full Text Available A fingerprint encryption scheme based on irreversible function has been designed in this paper. Since the fingerprint template includes almost the entire information of users’ fingerprints, the personal authentication can be determined only by the fingerprint features. This paper proposes an irreversible transforming function (using the improved SHA1 algorithm to transform the original minutiae which are extracted from the thinned fingerprint image. Then, Chinese remainder theorem is used to obtain the biokey from the integration of the transformed minutiae and the private key. The result shows that the scheme has better performance on security and efficiency comparing with other irreversible function schemes.

Seismic Shear Energy Reflection By Radon-Fourier Transform

Directory of Open Access Journals (Sweden)

Malik Umairia

2016-01-01

Full Text Available Seismic waves split in an anisotropic medium, instead of rotating horizontal component to principal direction, Radon-Fourier is derived to observe the signature of shear wave reflection. Synthetic model with fracture is built and discretized using finite difference scheme for spatial and time domain. Common depth point (CDP with single shot gives traces and automatic gain is preprocessed before Radon Transform (RT, a filtering technique gives radon domain. It makes easier to observe fractures at specific incidence and improves its quality in some way by removing the noise. A comparison of synthetic data and BF-data is performed on the basis of root means square error (RMS values. The RMS error is minimum at the 10th trace in radon domain.

Setting the Foundation for Transforming the U.S. Energy System

Energy Technology Data Exchange (ETDEWEB)

Davis, Jon M.; Virden, Jud W.; Walton, Terry L.; Brog, Terrence K.; Stiles, Dennis L.; Alderson, Karis P.; Melland, Jodi C.; Hobbs, Lori L.; Martinez, Sam J.; Quadrel, Marilyn J.; Quinn, Rod K.

2008-12-29

Setting the Foundation for Transforming the U.S. Energy System: Three Federal Action Plans for Near- and Long-term Success is a short document written for the incoming U.S. Federal Administration's Transistion Team. The document represents what we believe to be foundational elements of a broad campaign to make rapid progress towards these goals for the longterm transformation necessary to meet our national economic, security, and environmental goals. The three immediate action plans include: * Creating Tomorrow’s Electricity Infrastructure * Decarbonizing the Energy Economy *Enabling Science-Based Policy

Designing incentive schemes for promoting energy-efficient appliances: A new methodology and a case study for Spain

International Nuclear Information System (INIS)

Galarraga, Ibon; Abadie, Luis M.; Kallbekken, Steffen

2016-01-01

The energy-efficiency gap has been high on research and policy agendas for several decades. Incentive schemes such as subsidies, taxes and bonus-malus schemes are widely used to promote energy-efficient appliances. Most research, however, considers instruments in isolation, and only rarely in the context of political constraints on instrument use, or for alternative policy goals. This paper presents a methodology for the optimal design of incentive schemes based on the minimisation of Dead Weight Loss for different policy goals and policy restrictions. The use of the methodology is illustrated by designing optimal combinations of taxes and subsidies in Spain for three types of appliance: dishwashers, refrigerators and washing machines. The optimal policies are designed subject to different policy goals such as achieving a fixed reduction in emissions or a certain increased market share for efficient appliances, and for policy constraints such as budget neutrality. The methodology developed here can also be used to evaluate past and current incentive schemes. - Highlights: • A new methodology for the optimal design of incentive schemes is presented. • This is done minimising the Dead Weight Loss for different goals and restrictions. • Efficient bonus malus schemes can be designed with this method.

Analysis and performance assessment of a fragment retransmission scheme for energy efficient IEEE 802.11 WLANs.

Science.gov (United States)

Mafole, Prosper; Aritsugi, Masayoshi

2016-01-01

Backoff-free fragment retransmission (BFFR) scheme enhances the performance of legacy MAC layer fragmentation by eliminating contention overhead. The eliminated overhead is the result of backoff executed before a retransmission attempt is made when fragment transmission failure occurs within a fragment burst. This paper provides a mathematical analysis of BFFR energy efficiency and further assesses, by means of simulations, the energy efficiency, throughput and delay obtained when BFFR is used. The validity of the new scheme is evaluated in different scenarios namely, constant bit rate traffic, realistic bursty internet traffic, node mobility, rigid and elastic flows and their combinations at different traffic loads. We also evaluate and discuss the impact of BFFR on MAC fairness when the number of nodes is varied from 4 to 10. It is shown that BFFR has advantages over legacy MAC fragmentation scheme in all the scenarios.

Energy efficiency and SINR maximization beamformers for cognitive radio utilizing sensing information

KAUST Repository

Alabbasi, Abdulrahman

2014-06-01

In this paper we consider a cognitive radio multi-input multi-output environment in which we adapt our beamformer to maximize both energy efficiency and signal to interference plus noise ratio (SINR) metrics. Our design considers an underlaying communication using adaptive beamforming schemes combined with the sensing information to achieve an optimal energy efficient system. The proposed schemes maximize the energy efficiency and SINR metrics subject to cognitive radio and quality of service constraints. Since the optimization of energy efficiency problem is not a convex problem, we transform it into a standard semi-definite programming (SDP) form to guarantee a global optimal solution. Analytical solution is provided for one scheme, while the other scheme is left in a standard SDP form. Selected numerical results are used to quantify the impact of the sensing information on the proposed schemes compared to the benchmark ones.

Effect of a Green Investment Society on the Dutch Renewable Energy Scheme (SDE); Effect Groene Investeringsmaatschappij op SDE

Energy Technology Data Exchange (ETDEWEB)

Lensink, S.M.; Van Stralen, J. [ECN Beleidsstudies, Petten (Netherlands)

2012-11-27

On request of the Holland Financial Centre, ECN has projected the potential benefits of a Green Investment Company for the expenditure of the SDE+ Scheme (Renewable Energy Incentivisation Scheme). To this end, a calculation was made of the effects of an interest rebate for sustainable energy projects [Dutch] Op verzoek van Holland Financial Centre heeft ECN geraamd wat de voordelen kunnen zijn van een Groene Investeringsmaatschappij op de uitgaven voor de SDE+ (Stimuleringsregeling Duurzame Energie). Hiertoe diende een berekening gemaakt te worden van de effecten van een rentekorting voor duurzame energieprojecten.

Methodology for predicting market transformation due to implementation of energy efficiency standards and labels

International Nuclear Information System (INIS)

Mahlia, T.M.I.

2004-01-01

There are many papers that have been published on energy efficiency standards and labels. However, a very limited number of articles on the subject have discussed the transformation of appliance energy efficiency in the market after the programs are implemented. This paper is an attempt to investigate the market transformation due to implementation of minimum energy efficiency standards and energy labels. Even though the paper only investigates room air conditioners as a case study, the method is also applicable for predicting market transformation for other household electrical appliances

Biomass energy - Definitions, resources and transformation processes

International Nuclear Information System (INIS)

Damien, Alain

2013-01-01

Biomass energy is today considered as a new renewable energy source, and thus, has entered a regulatory framework aiming at encouraging its development for CO 2 pollution abatement. This book addresses the constraints, both natural and technological, of the exploitation of the biomass resource, and then the economical and regulatory aspects of this industry. This second edition provides a complement about the plants used and the new R and D progresses made in this domain. Content: 1 - Definitions and general considerations: natural organic products, regulatory and standardized definitions, energy aspects of biomass fuels; 2 - Resources: energy production dedicated crops, biomass by-products, biomass from wastes; 3 - Biomass to energy transformation processes: combustion, gasification, pyrolysis, torrefaction, methanation, alcoholic fermentation, landfill biogas, Fischer-Tropsch synthesis, methanol synthesis, trans-esterification, synthetic natural gas production, bio-hydrogen production; 4 - Biofuels: solid fuels, solid automotive biofuels, gaseous biofuels, liquid biofuels, comparative efficiency; 5 - Situation of biomass energy: regulations, impact on non-energy purpose biomass, advantages and drawbacks

Energy-Efficient Deadline-Aware Data-Gathering Scheme Using Multiple Mobile Data Collectors.

Science.gov (United States)

Dasgupta, Rumpa; Yoon, Seokhoon

2017-04-01

In wireless sensor networks, the data collected by sensors are usually forwarded to the sink through multi-hop forwarding. However, multi-hop forwarding can be inefficient due to the energy hole problem and high communications overhead. Moreover, when the monitored area is large and the number of sensors is small, sensors cannot send the data via multi-hop forwarding due to the lack of network connectivity. In order to address those problems of multi-hop forwarding, in this paper, we consider a data collection scheme that uses mobile data collectors (MDCs), which visit sensors and collect data from them. Due to the recent breakthroughs in wireless power transfer technology, MDCs can also be used to recharge the sensors to keep them from draining their energy. In MDC-based data-gathering schemes, a big challenge is how to find the MDCs' traveling paths in a balanced way, such that their energy consumption is minimized and the packet-delay constraint is satisfied. Therefore, in this paper, we aim at finding the MDCs' paths, taking energy efficiency and delay constraints into account. We first define an optimization problem, named the delay-constrained energy minimization (DCEM) problem, to find the paths for MDCs. An integer linear programming problem is formulated to find the optimal solution. We also propose a two-phase path-selection algorithm to efficiently solve the DCEM problem. Simulations are performed to compare the performance of the proposed algorithms with two heuristics algorithms for the vehicle routing problem under various scenarios. The simulation results show that the proposed algorithms can outperform existing algorithms in terms of energy efficiency and packet delay.

Static and dynamic efficiency of white certificate schemes; L'efficacite statique et dynamique des dispositifs de -certificats blancs-

Energy Technology Data Exchange (ETDEWEB)

Giraudet, L.G. [CIRED-ENPC, 94 - Nogent-sur-Marne (France); Finon, D. [CIRED-CNRS, 94 - Nogent-sur-Marne (France)

2011-07-15

White Certificate Schemes mandate energy companies to promote energy efficiency through flexibility mechanisms, including the trading of energy savings. They can be characterized as a quantity-based, baseline-and-credit system for the diffusion of energy efficient technologies. This paper compares experiences with White Certificate Schemes in Great Britain, Italy and France, in order to identify the basic drivers of each, and ultimately offer an original interpretation as an adaptive instrument, in the sense that it can take different forms in response to specific institutional contexts. A first analysis shows that Schemes perform well in terms of static efficiency, i.e. they are cost-effective and generate net social benefits over the period considered, though with large discrepancies rooted in different technological potentials. Regarding dynamic efficiency, i.e. the ability to induce and sustain technological change over the long haul, market transformation occurred in Great Britain, but was poorly incentivized in Italy and France by inadequate compliance cost recovery rules. Substantial organizational change has occurred in every country, mainly by strengthening vertical relationships between obliged parties and upstream businesses. Overall, the obligation (rather than the market component) drives the early phases of the Schemes. (authors)

Energy-Aware Multipath Routing Scheme Based on Particle Swarm Optimization in Mobile Ad Hoc Networks.

Science.gov (United States)

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.

IPv4 to IPv6 Transformation Schemes

Science.gov (United States)

Miyakawa, Shin

According to the recent observations of IPv4 (Internet Protocol version 4) address allocation status, it will be running out within few years. Consequently, to ensure the continuous extension of the Internet operation, introducing IPv6 (Internet Protocol version 6) protocol is surely needed. But at the same time, such transformation must be “smooth” for every Internet users and be compatible with today's IPv4 based practices. This paper describes several techniques and usage scenario which are discussed mainly in the IETF — Internet Engineering Task Force — and tried to be implemented as prototype products to transform today's Internet towards the IPv6 based one.

Energy-Efficient Data Gathering Scheme Based on Broadcast Transmissions in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Soobin Lee

2013-01-01

previous works have proposed ideas that reduce the energy consumption of the network by exploiting the spatial correlation between sensed information. In this paper, we propose a distributed data compression framework that exploits the broadcasting characteristic of the wireless medium to improve energy efficiency. We analyze the performance of the proposed framework numerically and compare it with the performance of previous works using simulation. The proposed scheme performs better when the sensing information is correlated.

A soft computing scheme incorporating ANN and MOV energy in fault detection, classification and distance estimation of EHV transmission line with FSC.

Science.gov (United States)

Khadke, Piyush; Patne, Nita; Singh, Arvind; Shinde, Gulab

2016-01-01

In this article, a novel and accurate scheme for fault detection, classification and fault distance estimation for a fixed series compensated transmission line is proposed. The proposed scheme is based on artificial neural network (ANN) and metal oxide varistor (MOV) energy, employing Levenberg-Marquardt training algorithm. The novelty of this scheme is the use of MOV energy signals of fixed series capacitors (FSC) as input to train the ANN. Such approach has never been used in any earlier fault analysis algorithms in the last few decades. Proposed scheme uses only single end measurement energy signals of MOV in all the 3 phases over one cycle duration from the occurrence of a fault. Thereafter, these MOV energy signals are fed as input to ANN for fault distance estimation. Feasibility and reliability of the proposed scheme have been evaluated for all ten types of fault in test power system model at different fault inception angles over numerous fault locations. Real transmission system parameters of 3-phase 400 kV Wardha-Aurangabad transmission line (400 km) with 40 % FSC at Power Grid Wardha Substation, India is considered for this research. Extensive simulation experiments show that the proposed scheme provides quite accurate results which demonstrate complete protection scheme with high accuracy, simplicity and robustness.

A scoping study on energy-efficiency market transformation by California Utility DSM Programs

Energy Technology Data Exchange (ETDEWEB)

Eto, J.; Prahl, R.; Schlegel, J.

1996-07-01

Market transformation has emerged as a central policy objective for future publicly-funded energy-efficiency programs in California. California Public Utilities Commission (CPUC) Decision 95-12-063 calls for public funding to shift to activities designed to transform the energy-efficiency market. The CPUC envisions that funding {open_quotes}would only be needed for specific and limited periods of time to cause the market to be transformed{close_quotes}. At the same time, the CPUC also acknowledges that {open_quotes}there are many definitions of market transformation{close_quotes} ... and does {open_quotes}not attempt to refine those definitions today{close_quotes}. We argue that a definition of market transformation is essential. The literature is now replete with definitions, and an operational definition is needed for the CPUC to decide on which programs should be supported with public funds. The CPUC decision initially indicated a preference for programs that do not provide financial assistance 4-efficiency programs that rely on financial assistance to customers. However, energy customers have traditionally accounted for a substantial portion of California utility`s DSM programs, so the CPUC`s direction to use ratepayer funds to support programs that will transform the market raises critical questions about how to analyze what has happened in order to plan effectively for the future: Which utility energy-efficiency programs, including those that provide financial assistance to customers, have had market transforming effects? To what extent do current regulatory rules and practices encourage or discourage utilities from running programs that are designed to transform the market? Should the rules and programs be modified, and, if so, how, to promote market transformation?

[Neoplastic transformation of mouse fibroblasts under the influence of high-energy protons and gamma-rays].

Science.gov (United States)

Voskanian, K Sh

2004-01-01

Oncoginic transformations of mouse fibroblasts C3H10T1/2 after exposure to proton energies 150 and 584 MeV were compared with fibroblast effects of gamma-radiation. Prior to exposure, cell populations (2.7 x 10(3) cells/cm2) were inoculated in plastic vials with the surface area of 75 cm2 and cultivated 11 days. Survivability was determined by comparing the number of cell colonies in irradiated and non-irradiated (control) vials. Transformation rate was calculated by dividing the total transformation focus number by the number of survived cells in a vial. Rate of oncogenic transformations after gamma- and proton (584 MeV) irradiation was essentially identical, i.e. the parameter grew rapidly at the doses 1 Gy. In the dose interval between 1 and 5 Gy, transformation rate for proton energy 150 MeV was found low compared with gamma-radiation and proton energy 584 MeV. It is hypothesized that the different transformation rate after exposure to proton energy 150 MeV is linked with the high linear energy transfer as compared with the proton energy of 584 MeV and gamma-radiation.

Automated image enhancement using power law transformations

Indian Academy of Sciences (India)

We propose a scheme for automating power law transformations which are used for image enhancement. The scheme we propose does not require the user to choose the exponent in the power law transformation. This method works well for images having poor contrast, especially to those images in which the peaks ...

Novel Directional Protection Scheme for the FREEDM Smart Grid System

Science.gov (United States)

Sharma, Nitish

This research primarily deals with the design and validation of the protection system for a large scale meshed distribution system. The large scale system simulation (LSSS) is a system level PSCAD model which is used to validate component models for different time-scale platforms, to provide a virtual testing platform for the Future Renewable Electric Energy Delivery and Management (FREEDM) system. It is also used to validate the cases of power system protection, renewable energy integration and storage, and load profiles. The protection of the FREEDM system against any abnormal condition is one of the important tasks. The addition of distributed generation and power electronic based solid state transformer adds to the complexity of the protection. The FREEDM loop system has a fault current limiter and in addition, the Solid State Transformer (SST) limits the fault current at 2.0 per unit. Former students at ASU have developed the protection scheme using fiber-optic cable. However, during the NSF-FREEDM site visit, the National Science Foundation (NSF) team regarded the system incompatible for the long distances. Hence, a new protection scheme with a wireless scheme is presented in this thesis. The use of wireless communication is extended to protect the large scale meshed distributed generation from any fault. The trip signal generated by the pilot protection system is used to trigger the FID (fault isolation device) which is an electronic circuit breaker operation (switched off/opening the FIDs). The trip signal must be received and accepted by the SST, and it must block the SST operation immediately. A comprehensive protection system for the large scale meshed distribution system has been developed in PSCAD with the ability to quickly detect the faults. The validation of the protection system is performed by building a hardware model using commercial relays at the ASU power laboratory.

A Sleep-Awake Scheme Based on CoAP for Energy-Efficiency in Internet of Things

Directory of Open Access Journals (Sweden)

Wenquan Jin

2017-11-01

Full Text Available Internet Engineering Task Force (IETF have developed Constrained Application Protocol (CoAP to enable communication between sensor or actuator nodes in constrained environments, such as small amount of memory, and low power. IETF CoAP and HTTP are used to monitor or control environments in Internet of Things (IoT and Machine-to-Machine (M2M. In this paper, we present a sleep-awake scheme based on CoAP for energy efficiency in Internet of Things. This scheme supports to increase energy efficiency of IoT nodes using CoAP protocol. We have slightly modified the IoT middleware to improve CoAP protocol to conserve energy in the IoT nodes. Also, the IoT middleware includes some functionality of the CoRE Resource Directory (RD and the Message Queue (MQ broker with IoT nodes to synchronize sleepy status.

Study on rice transformation mediated by low energy ion beam implantation

International Nuclear Information System (INIS)

Li Hong; Wu Lifang; Yu Zengliang

2001-01-01

Delivery of foreign DNA into rice via ion beam was first reported in 1994. In recent years we have aimed to set up efficient transformation system mediated by low energy ion beam. The factors that influence the transformation including type of ion, parameters of ion energy, dose and dose rate, plant genotype, composition of media, concentration of hormones and antibiotics were carefully investigated. Treated with 25ke V Ar + , the transformation efficiencies of the mature embryos of rice variety 02428, Hua pei94-jian-09 and Minghui63 reached 11%, 11.4% and 7.1% measured by produced antibiotic resistant callus and l.52%, 1.87% and l.13% measured by regenerated plants respectively. PCR detection and Southern blot analysis showed that GUS report gene had inserted in rice genome. Low energy ion beam mediated gene transfer will be extended to other cereal recalcitrant to Agrobacterium tumefaciens as soon as methodological parameters were optimized. (authors)

Energy landscape for martensitic phase transformation in shape memory NiTi

International Nuclear Information System (INIS)

Kibey, S.; Sehitoglu, H.; Johnson, D.D.

2009-01-01

First-principles calculations are presented for parent B2 phase and martensitic B19 and B19' phases in NiTi. The results indicate that both B19 and B19' are energetically more stable than the parent B2 phase. By means of ab initio density functional theory, the complete distortion-shuffle energy landscape associated with B2 → B19 transformation in NiTi is then determined. In addition to accounting for the Bain-type deformation through the Cauchy-Born rule, the study explicitly accounts for the shuffle displacements experienced by the internal ions in NiTi. The energy landscape allows the energy barrier associated with the B2 → B19 transformation pathway to be identified. The results indicate that a barrier of 0.48 mRyd atom -1 (relative to the B2 phase) must be overcome to transform the parent B2 NiTi to orthorhombic B19 martensite

Compatible, energy conserving, bounds preserving remap of hydrodynamic fields for an extended ALE scheme

Science.gov (United States)

Burton, D. E.; Morgan, N. R.; Charest, M. R. J.; Kenamond, M. A.; Fung, J.

2018-02-01

From the very origins of numerical hydrodynamics in the Lagrangian work of von Neumann and Richtmyer [83], the issue of total energy conservation as well as entropy production has been problematic. Because of well known problems with mesh deformation, Lagrangian schemes have evolved into Arbitrary Lagrangian-Eulerian (ALE) methods [39] that combine the best properties of Lagrangian and Eulerian methods. Energy issues have persisted for this class of methods. We believe that fundamental issues of energy conservation and entropy production in ALE require further examination. The context of the paper is an ALE scheme that is extended in the sense that it permits cyclic or periodic remap of data between grids of the same or differing connectivity. The principal design goals for a remap method then consist of total energy conservation, bounded internal energy, and compatibility of kinetic energy and momentum. We also have secondary objectives of limiting velocity and stress in a non-directional manner, keeping primitive variables monotone, and providing a higher than second order reconstruction of remapped variables. In particular, the new contributions fall into three categories associated with: energy conservation and entropy production, reconstruction and bounds preservation of scalar and tensor fields, and conservative remap of nonlinear fields. The paper presents a derivation of the methods, details of implementation, and numerical results for a number of test problems. The methods requires volume integration of polynomial functions in polytopal cells with planar facets, and the requisite expressions are derived for arbitrary order.

Energy Barriers and Hysteresis in Martensitic Phase Transformations

Science.gov (United States)

2008-08-01

glacial acetic acid (CH3COOH) and 10-15% perchloric acid (HCLO4) by volume, the cathode was stainless steel , the anode was stainless steel or Ti, the...Submitted to Acta Materialia Energy barriers and hysteresis in martensitic phase transformations Zhiyong Zhang, Richard D. James and Stefan Müller...hysteresis based on the growth from a small scale of fully developed austenite martensite needles. In this theory the energy of the transition layer plays a

The evolution of the support scheme for promoting renewable energy sources in Romania

Directory of Open Access Journals (Sweden)

Atănăsoae Pavel

2016-01-01

Full Text Available The paper presents an analysis of the evolution of the support scheme for promoting renewable energy sources in Romania, following: the annual mandatory quotas of green certificate purchase and those achieved; the price of green certificates; the evolution of the RES-E installed capacity and implicitly of the investments in renewable energy sources; the structure of the installed power in RES-E (wind power plants, photovoltaic power plants, hydroelectric power plants with an installed capacity that is not larger than 10 MW, biomass power plants; the contribution of the renewable energy sources to the production of electricity in Romania.

ECG denoising with adaptive bionic wavelet transform.

Science.gov (United States)

Sayadi, Omid; Shamsollahi, Mohammad Bagher

2006-01-01

In this paper a new ECG denoising scheme is proposed using a novel adaptive wavelet transform, named bionic wavelet transform (BWT), which had been first developed based on a model of the active auditory system. There has been some outstanding features with the BWT such as nonlinearity, high sensitivity and frequency selectivity, concentrated energy distribution and its ability to reconstruct signal via inverse transform but the most distinguishing characteristic of BWT is that its resolution in the time-frequency domain can be adaptively adjusted not only by the signal frequency but also by the signal instantaneous amplitude and its first-order differential. Besides by optimizing the BWT parameters parallel to modifying a new threshold value, one can handle ECG denoising with results comparing to those of wavelet transform (WT). Preliminary tests of BWT application to ECG denoising were constructed on the signals of MIT-BIH database which showed high performance of noise reduction.

Modelling and study on the output flow characteristics of expansion energy used hydropneumatic transformer

Energy Technology Data Exchange (ETDEWEB)

Shi, Yan; Wu, Tiecheng; Cai, Maolin; Liu, Chong [Beihang University, Beijing (China)

2016-03-15

Hydropneumatic transformer (short for HP transformer) is used to pump pressurized hydraulic oil. Whereas, due to its insufficient usage of energy and low efficiency, a new kind of HP transformer: EEUHP transformer (Expansion energy used hydropneumatic transformer) was proposed. To illustrate the characteristics of the EEUHP transformer, a mathematical model was built. To verify the mathematical model, an experimental prototype was setup and studied. Through simulation and experimental study on the EEUHP transformer, the influence of five key parameters on the output flow of the EEUHP transformer were obtained, and some conclusions can be drawn. Firstly, the mathematical model was proved to be valid. Furthermore, the EEUHP transformer costs fewer of compressed air than the normal HP transformer when the output flow of the two kinds of transformers are almost same. Moreover, with an increase in the output pressure, the output flow decreases sharply. Finally, with an increase in the effective area of hydraulic output port, the output flow increases distinctly. This research can be referred to in the performance and design optimization of the EEUHP transformers.

MODELING OF THREE-PHASE THREE LEG TRANSFORMER DEVICES FOR ENGINEERING CALCULATIONS OF ASYMMETRICAL MODES FOR DIFFERENT SCHEMES OF WINDING CONNECTIONS

Directory of Open Access Journals (Sweden)

Bosneaga V.A

2013-08-01

Full Text Available The model is proposed for the calculation and research of steady state asymmetric modes and transients in three-phase three legs transformer devices with arbitrary diagram of windings connection, taking into account the electromagnetic coupling of the windings, located on different legs. Using as an example distribution transformer of 10/0.4 kV calculations and analysis were performed of the most characteristic steady asymmetrical modes, that occur during short circuit, phase failure, unbalanced load for the most common windings connections and, in particular, associated with the occurrence of zero sequence magnetic flow. For the considered regimes and schemes vector diagrams were constructed for currents and voltages as well as for the relative values of magnetic flow, which give a clear idea about their particular features.

Energy conserving schemes for the simulation of musical instrument contact dynamics

Science.gov (United States)

Chatziioannou, Vasileios; van Walstijn, Maarten

2015-03-01

Collisions are an innate part of the function of many musical instruments. Due to the nonlinear nature of contact forces, special care has to be taken in the construction of numerical schemes for simulation and sound synthesis. Finite difference schemes and other time-stepping algorithms used for musical instrument modelling purposes are normally arrived at by discretising a Newtonian description of the system. However because impact forces are non-analytic functions of the phase space variables, algorithm stability can rarely be established this way. This paper presents a systematic approach to deriving energy conserving schemes for frictionless impact modelling. The proposed numerical formulations follow from discretising Hamilton's equations of motion, generally leading to an implicit system of nonlinear equations that can be solved with Newton's method. The approach is first outlined for point mass collisions and then extended to distributed settings, such as vibrating strings and beams colliding with rigid obstacles. Stability and other relevant properties of the proposed approach are discussed and further demonstrated with simulation examples. The methodology is exemplified through a case study on tanpura string vibration, with the results confirming the main findings of previous studies on the role of the bridge in sound generation with this type of string instrument.

Simplified scheme for energy in the world in 2050

International Nuclear Information System (INIS)

Bouneau, S.; David, S.; Loiseaux, J.M.; Meplan, O.; Treiner, J.

2013-01-01

We have built a scheme for predicting the world energy mix in 2050. We have divided the world into 4 economically equivalent areas and the population into 3 types depending on their standard of living. 2 constraints have been added. First the climatic constraint: we impose to reduce by 2050 by a factor 2 the today's releases of CO 2 due to energy uses. Secondly we have limited the worldwide energy consumption to 20 Gtep/year in 2050, this limit is in fact an average value made on various existing perspective studies, in 2009 this consumption neared 12 Gtep a year. In the first step the global energy demand (20 Gtep a year) has been broken into the 4 main consumption sectors (transport, industry, households, electrical power) for the 3 types of population. The second step has been to assess the potential of renewable energies: compared to 2008 figures, the wind power is expected to grow by a factor 20 while photovoltaic power will grow by a factor 2000, carbon sequestration is expected to be used at a rate between 0.25 and 0.66 tep/inhabitant/year. The third step has been to build an energy mix meeting the constraints and expectations. The results show that it seems almost impossible to assure a worldwide economic growth and to comply with the climatic constraint without the development of both nuclear energy and carbon sequestration. Another striking result is that the lack of enough energy resources for transport and heating will lead to more demand on electricity while present French standards favor gas and oil-fired heating. (A.C.)

Optimal Face-Iris Multimodal Fusion Scheme

Directory of Open Access Journals (Sweden)

Omid Sharifi

2016-06-01

Full Text Available Multimodal biometric systems are considered a way to minimize the limitations raised by single traits. This paper proposes new schemes based on score level, feature level and decision level fusion to efficiently fuse face and iris modalities. Log-Gabor transformation is applied as the feature extraction method on face and iris modalities. At each level of fusion, different schemes are proposed to improve the recognition performance and, finally, a combination of schemes at different fusion levels constructs an optimized and robust scheme. In this study, CASIA Iris Distance database is used to examine the robustness of all unimodal and multimodal schemes. In addition, Backtracking Search Algorithm (BSA, a novel population-based iterative evolutionary algorithm, is applied to improve the recognition accuracy of schemes by reducing the number of features and selecting the optimized weights for feature level and score level fusion, respectively. Experimental results on verification rates demonstrate a significant improvement of proposed fusion schemes over unimodal and multimodal fusion methods.

Transformer ratio enhancement experiment

International Nuclear Information System (INIS)

Gai, W.; Power, J. G.; Kanareykin, A.; Neasheva, E.; Altmark, A.

2004-01-01

Recently, a multibunch scheme for efficient acceleration based on dielectric wakefield accelerator technology was outlined in J.G. Power, W. Gai, A. Kanareykin, X. Sun. PAC 2001 Proceedings, pp. 114-116, 2002. In this paper we present an experimental program for the design, development and demonstration of an Enhanced Transformer Ratio Dielectric Wakefield Accelerator (ETR-DWA). The principal goal is to increase the transformer ratio R, the parameter that characterizes the energy transfer efficiency from the accelerating structure to the accelerated electron beam. We present here an experimental design of a 13.625 GHz dielectric loaded accelerating structure, a laser multisplitter producing a ramped bunch train, and simulations of the bunch train parameters required. Experimental results of the accelerating structure bench testing and ramped pulsed train generation with the laser multisplitter are shown as well. Using beam dynamic simulations, we also obtain the focusing FODO lattice parameters

GGA+U study of uranium mononitride: A comparison of the U-ramping and occupation matrix schemes and incorporation energies of fission products

Energy Technology Data Exchange (ETDEWEB)

Claisse, Antoine, E-mail: claisse@kth.se [KTH Royal Institute of Technology, Reactor Physics, AlbaNova University Centre, 106 91 Stockholm (Sweden); Klipfel, Marco [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, D-76125 Karlsruhe (Germany); Lindbom, Niclas [KTH Royal Institute of Technology, Reactor Physics, AlbaNova University Centre, 106 91 Stockholm (Sweden); Freyss, Michel [CEA, DEN, DEC, Centre de Cadarache, 13108 Saint-Paul-lez-Durance (France); Olsson, Pär [KTH Royal Institute of Technology, Reactor Physics, AlbaNova University Centre, 106 91 Stockholm (Sweden)

2016-09-15

Uranium mononitride is studied in the DFT + U framework. Its ground state is investigated and a study of the incorporation of diverse fission products in the crystal is conducted. The U-ramping and occupation matrix control (OMC) schemes are used to eliminate metastable states. Beyond a certain amount of introduced correlation, the OMC scheme starts to find a lower total energy. The OMC scheme is chosen for the second part of this study. Furthermore, the influence of the magnetic ordering is studied using the U-ramping method, showing that antiferromagnetic order is the most stable one when the U parameter is larger than 1.75 eV. The effect on the density of states is investigated and elastic constants are provided for comparison with other methods and experiments. The incorporation energies of fission products in different defect configurations are calculated and these energies are corrected to take into account the limited size of the supercell. - Highlights: • We studied bulk uranium nitride with means of DFT+U with the U-ramping scheme and the OMC scheme. • We produces a density of states plot and calculated the elastic constants of UN. • We calculated the incorporation energy of many fission products in UN, and corrected them to take into account the elastic interactions. • The OMC scheme should be used over the U-ramping scheme. • Fission products go to larger crystal sites.

Application of the Broad Energy Germanium detector: A technique for elucidating β-decay schemes which involve daughter nuclei with very low energy excited states

Energy Technology Data Exchange (ETDEWEB)

Venhart, M., E-mail: martin.venhart@savba.sk [Institute of Physics, Slovak Academy of Sciences, SK-84511 Bratislava (Slovakia); Wood, J.L. [Department of Physics, Georgia Institute of Technology, Atlanta GA 30332 (United States); Boston, A.J. [Institute of Physics, Slovak Academy of Sciences, SK-84511 Bratislava (Slovakia); Cocolios, T.E. [School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL (United Kingdom); KU Leuven, Instituut voor Kern, en Stralingsfysica, B-3001 Leuven (Belgium); Harkness-Brennan, L.J.; Herzberg, R.-D.; Joss, D.T.; Judson, D.S. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Kliman, J.; Matoušek, V. [Institute of Physics, Slovak Academy of Sciences, SK-84511 Bratislava (Slovakia); Motyčák, Š. [Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, SK-812 19 Bratislava (Slovakia); Page, R.D.; Patel, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Petrík, K.; Sedlák, M.; Veselský, M. [Institute of Physics, Slovak Academy of Sciences, SK-84511 Bratislava (Slovakia)

2017-03-21

A technique for elucidating β-decay schemes of isotopes with a large density of states at low excitation energy has been developed, in which a Broad Energy Germanium (BEGe) detector is used in conjunction with coaxial hyper-pure germanium detectors. The power of this technique is demonstrated using the example of {sup 183}Hg decay. Mass-separated samples of {sup 183}Hg were produced by a deposition of the low-energy radioactive-ion beam delivered by the ISOLDE facility at CERN. The excellent energy resolution of the BEGe detector allowed γ-ray energies to be determined with a precision of a few tens of eV, which was sufficient for the analysis of the Rydberg-Ritz combinations (in conjunction with γ-γ coincidences) in the level scheme. The timestamped structure of the data was used for unambiguous separation of γ rays arising from the decay of {sup 183}Hg from those due to the daughter decays.

Micro-generation schemes: user behaviours and attitudes towards energy consumption.

Science.gov (United States)

Stedmon, Alex W; Winslow, Robin; Langley, Alyson

2013-01-01

In the last decade, there has been increasing pressure on developed nations to reduce their carbon emissions. Distributed micro-generation (MG) initiatives provide incentives for small-scale renewable energy generation, particularly by residential home-owners. This paper investigates the existing knowledge base to consider if living in a property with on-site renewable electricity generation may affect user attitudes and behaviours. This knowledge is interpreted from a human factors perspective by focussing on individual behaviour and social learning as well as identifying underlying user requirements and user needs. Suggestions are then made with regard to the effects that MG schemes may have on public attitudes and where further research efforts should be focused. There is evidence that renewable energy initiatives are likely to result in a shift in public behaviour, particularly towards reduced energy consumption where mechanisms for increased feedback can act as a facilitator to learning and motivator to change. The role of human factors/ergonomics in supporting renewable energy initiatives has not been fully exploited. A range of case studies explore user needs and awareness of renewable energy, presenting mixed evidence for reduced consumption. However, individual behaviour and social learning can be influenced through increased feedback that acts as a facilitator to change.

Time-division-multiplex control scheme for voltage multiplier rectifiers

Directory of Open Access Journals (Sweden)

Bin-Han Liu

2017-03-01

Full Text Available A voltage multiplier rectifier with a novel time-division-multiplexing (TDM control scheme for high step-up converters is proposed in this study. In the proposed TDM control scheme, two full-wave voltage doubler rectifiers can be combined to realise a voltage quadrupler rectifier. The proposed voltage quadrupler rectifier can reduce transformer turn ratio and transformer size for high step-up converters and also reduce voltage stress for the output capacitors and rectifier diodes. An N-times voltage rectifier can be straightforwardly produced by extending the concepts from the proposed TDM control scheme. A phase-shift full-bridge (PSFB converter is adopted in the primary side of the proposed voltage quadrupler rectifier to construct a PSFB quadrupler converter. Experimental results for the PSFB quadrupler converter demonstrate the performance of the proposed TDM control scheme for voltage quadrupler rectifiers. An 8-times voltage rectifier is simulated to determine the validity of extending the proposed TDM control scheme to realise an N-times voltage rectifier. Experimental and simulation results show that the proposed TDM control scheme has great potential to be used in high step-up converters.

Achieving Smart Energy Planning Objectives. The Approach of the Transform Project

Directory of Open Access Journals (Sweden)

Ilaria Delponte

2014-05-01

Full Text Available Cities play a dual role in the field of energy and integrated planning. They function as institutional planning and decision making bodies and interfere as actors, e.g. as project developers or launching customers. In the first case their attempts at integrated plans are often unsuccessful in integrating vision, goals and instruments of all stakeholders so that waste, water, energy cycles, urban planning and budgets proceed with no connection to each other.  TRANSFORM Project “Transformation Agenda for Low Carbon Cities” (FP7 tries to improve the integrated energy policy and decision making process of cities, both at a strategic and operational level, by providing the cities with a framework based on overall planning experiences and on-the-field projects and qualitative and quantitative analysis support models. The project intends also to make a step further in the quality of research, by providing a replicable and tested framework for the production of a strategic Transformation Agenda for the city as a whole, combined with district Implementation Plans.

Generalising tree traversals and tree transformations to DAGs

DEFF Research Database (Denmark)

Bahr, Patrick; Axelsson, Emil

2017-01-01

We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead. The resul......We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead...... as the complementing theory with a number of examples....

Multiresolution signal decomposition schemes. Part 2: Morphological wavelets

NARCIS (Netherlands)

H.J.A.M. Heijmans (Henk); J. Goutsias (John)

1999-01-01

htmlabstractIn its original form, the wavelet transform is a linear tool. However, it has been increasingly recognized that nonlinear extensions are possible. A major impulse to the development of nonlinear wavelet transforms has been given by the introduction of the lifting scheme by Sweldens. The

Good governance for pension schemes

CERN Document Server

Thornton, Paul

2011-01-01

Regulatory and market developments have transformed the way in which UK private sector pension schemes operate. This has increased demands on trustees and advisors and the trusteeship governance model must evolve in order to remain fit for purpose. This volume brings together leading practitioners to provide an overview of what today constitutes good governance for pension schemes, from both a legal and a practical perspective. It provides the reader with an appreciation of the distinctive characteristics of UK occupational pension schemes, how they sit within the capital markets and their social and fiduciary responsibilities. Providing a holistic analysis of pension risk, both from the trustee and the corporate perspective, the essays cover the crucial role of the employer covenant, financing and investment risk, developments in longevity risk hedging and insurance de-risking, and best practice scheme administration.

Influence of India’s transformation on residential energy demand

International Nuclear Information System (INIS)

Bhattacharyya, Subhes C.

2015-01-01

Highlights: • The middle income group emerges as the dominant segment by 2030. • Commercial residential energy demand increases 3–4 folds compared to 2010. • Electricity and LPG demand grows above 6% per year in the reference scenario. • India faces the potential of displacing the domination of biomass by 2030. - Abstract: India’s recent macro-economic and structural changes are transforming the economy and bringing significant changes to energy demand behaviour. Life-style and consumption behaviour are evolving rapidly due to accelerated economic growth in recent times. The population structure is changing, thereby offering the country with the potential to reap the population dividend. The country is also urbanising rapidly, and the fast-growing middle class segment of the population is fuelling consumerism by mimicking international life-styles. These changes are likely to have significant implications for energy demand in the future, particularly in the residential sector. Using the end-use approach of demand analysis, this paper analyses how residential energy demand is likely to evolve as a consequence of India’s transformation and finds that by 2030, India’s commercial energy demand in the residential sector can quadruple in the high scenario compared to the demand in 2010. Demand for modern fuels like electricity and liquefied petroleum gas is likely to grow at a faster rate. However, there is a window of opportunity to better manage the evolution of residential demand in India through energy efficiency improvement

Estimating the CCSD basis-set limit energy from small basis sets: basis-set extrapolations vs additivity schemes

Energy Technology Data Exchange (ETDEWEB)

Spackman, Peter R.; Karton, Amir, E-mail: amir.karton@uwa.edu.au [School of Chemistry and Biochemistry, The University of Western Australia, Perth, WA 6009 (Australia)

2015-05-15

Coupled cluster calculations with all single and double excitations (CCSD) converge exceedingly slowly with the size of the one-particle basis set. We assess the performance of a number of approaches for obtaining CCSD correlation energies close to the complete basis-set limit in conjunction with relatively small DZ and TZ basis sets. These include global and system-dependent extrapolations based on the A + B/L{sup α} two-point extrapolation formula, and the well-known additivity approach that uses an MP2-based basis-set-correction term. We show that the basis set convergence rate can change dramatically between different systems(e.g.it is slower for molecules with polar bonds and/or second-row elements). The system-dependent basis-set extrapolation scheme, in which unique basis-set extrapolation exponents for each system are obtained from lower-cost MP2 calculations, significantly accelerates the basis-set convergence relative to the global extrapolations. Nevertheless, we find that the simple MP2-based basis-set additivity scheme outperforms the extrapolation approaches. For example, the following root-mean-squared deviations are obtained for the 140 basis-set limit CCSD atomization energies in the W4-11 database: 9.1 (global extrapolation), 3.7 (system-dependent extrapolation), and 2.4 (additivity scheme) kJ mol{sup –1}. The CCSD energy in these approximations is obtained from basis sets of up to TZ quality and the latter two approaches require additional MP2 calculations with basis sets of up to QZ quality. We also assess the performance of the basis-set extrapolations and additivity schemes for a set of 20 basis-set limit CCSD atomization energies of larger molecules including amino acids, DNA/RNA bases, aromatic compounds, and platonic hydrocarbon cages. We obtain the following RMSDs for the above methods: 10.2 (global extrapolation), 5.7 (system-dependent extrapolation), and 2.9 (additivity scheme) kJ mol{sup –1}.

Estimating the CCSD basis-set limit energy from small basis sets: basis-set extrapolations vs additivity schemes

International Nuclear Information System (INIS)

Spackman, Peter R.; Karton, Amir

2015-01-01

Coupled cluster calculations with all single and double excitations (CCSD) converge exceedingly slowly with the size of the one-particle basis set. We assess the performance of a number of approaches for obtaining CCSD correlation energies close to the complete basis-set limit in conjunction with relatively small DZ and TZ basis sets. These include global and system-dependent extrapolations based on the A + B/L α two-point extrapolation formula, and the well-known additivity approach that uses an MP2-based basis-set-correction term. We show that the basis set convergence rate can change dramatically between different systems(e.g.it is slower for molecules with polar bonds and/or second-row elements). The system-dependent basis-set extrapolation scheme, in which unique basis-set extrapolation exponents for each system are obtained from lower-cost MP2 calculations, significantly accelerates the basis-set convergence relative to the global extrapolations. Nevertheless, we find that the simple MP2-based basis-set additivity scheme outperforms the extrapolation approaches. For example, the following root-mean-squared deviations are obtained for the 140 basis-set limit CCSD atomization energies in the W4-11 database: 9.1 (global extrapolation), 3.7 (system-dependent extrapolation), and 2.4 (additivity scheme) kJ mol –1 . The CCSD energy in these approximations is obtained from basis sets of up to TZ quality and the latter two approaches require additional MP2 calculations with basis sets of up to QZ quality. We also assess the performance of the basis-set extrapolations and additivity schemes for a set of 20 basis-set limit CCSD atomization energies of larger molecules including amino acids, DNA/RNA bases, aromatic compounds, and platonic hydrocarbon cages. We obtain the following RMSDs for the above methods: 10.2 (global extrapolation), 5.7 (system-dependent extrapolation), and 2.9 (additivity scheme) kJ mol –1

An improved fault detection classification and location scheme based on wavelet transform and artificial neural network for six phase transmission line using single end data only.

Science.gov (United States)

Koley, Ebha; Verma, Khushaboo; Ghosh, Subhojit

2015-01-01

Restrictions on right of way and increasing power demand has boosted development of six phase transmission. It offers a viable alternative for transmitting more power, without major modification in existing structure of three phase double circuit transmission system. Inspite of the advantages, low acceptance of six phase system is attributed to the unavailability of a proper protection scheme. The complexity arising from large number of possible faults in six phase lines makes the protection quite challenging. The proposed work presents a hybrid wavelet transform and modular artificial neural network based fault detector, classifier and locator for six phase lines using single end data only. The standard deviation of the approximate coefficients of voltage and current signals obtained using discrete wavelet transform are applied as input to the modular artificial neural network for fault classification and location. The proposed scheme has been tested for all 120 types of shunt faults with variation in location, fault resistance, fault inception angles. The variation in power system parameters viz. short circuit capacity of the source and its X/R ratio, voltage, frequency and CT saturation has also been investigated. The result confirms the effectiveness and reliability of the proposed protection scheme which makes it ideal for real time implementation.

How can conceptual schemes change teaching?

Science.gov (United States)

Wickman, Per-Olof

2012-03-01

Lundqvist, Almqvist and Östman describe a teacher's manner of teaching and the possible consequences it may have for students' meaning making. In doing this the article examines a teacher's classroom practice by systematizing the teacher's transactions with the students in terms of certain conceptual schemes, namely the epistemological moves, educational philosophies and the selective traditions of this practice. In connection to their study one may ask how conceptual schemes could change teaching. This article examines how the relationship of the conceptual schemes produced by educational researchers to educational praxis has developed from the middle of the last century to today. The relationship is described as having been transformed in three steps: (1) teacher deficit and social engineering, where conceptual schemes are little acknowledged, (2) reflecting practitioners, where conceptual schemes are mangled through teacher practice to aid the choices of already knowledgeable teachers, and (3) the mangling of the conceptual schemes by researchers through practice with the purpose of revising theory.

Sources of funding for community schemes

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-01

There is an increasing level of interest amongst community groups in the UK to become involved in the development of renewable energy schemes. Often however these community groups have only limited funds of their own, so any additional funds that can be identified to help fund their renewable energy scheme can be very useful. There are a range of funding sources available that provide grants or loans for which community groups are eligible to apply. Few of these funding sources are targeted towards renewable energy specifically, nevertheless the funds may be applicable to renewable energy schemes under appropriate circumstances. To date, however, few of these funds have been accessed by community groups for renewable energy initiatives. One of the reasons for this low take-up of funds on offer could be that the funding sources may be difficult and time-consuming to identify, especially where the energy component of the fund is not readily apparent. This directory draws together details about many of the principal funding sources available in the UK that may consider providing funds to community groups wanting to develop a renewable energy scheme. (author)

Biorthogonal projected energies of a Gutzwiller similarity transformed Hamiltonian.

Science.gov (United States)

Wahlen-Strothman, J M; Scuseria, G E

2016-12-07

We present a method incorporating biorthogonal orbital-optimization, symmetry projection, and double-occupancy screening with a non-unitary similarity transformation generated by the Gutzwiller factor [Formula: see text], and apply it to the Hubbard model. Energies are calculated with mean-field computational scaling with high-quality results comparable to coupled cluster singles and doubles. This builds on previous work performing similarity transformations with more general, two-body Jastrow-style correlators. The theory is tested on 2D lattices ranging from small systems into the thermodynamic limit and is compared to available reference data.

Towards the ultimate variance-conserving convection scheme

International Nuclear Information System (INIS)

Os, J.J.A.M. van; Uittenbogaard, R.E.

2004-01-01

In the past various arguments have been used for applying kinetic energy-conserving advection schemes in numerical simulations of incompressible fluid flows. One argument is obeying the programmed dissipation by viscous stresses or by sub-grid stresses in Direct Numerical Simulation and Large Eddy Simulation, see e.g. [Phys. Fluids A 3 (7) (1991) 1766]. Another argument is that, according to e.g. [J. Comput. Phys. 6 (1970) 392; 1 (1966) 119], energy-conserving convection schemes are more stable i.e. by prohibiting a spurious blow-up of volume-integrated energy in a closed volume without external energy sources. In the above-mentioned references it is stated that nonlinear instability is due to spatial truncation rather than to time truncation and therefore these papers are mainly concerned with the spatial integration. In this paper we demonstrate that discretized temporal integration of a spatially variance-conserving convection scheme can induce non-energy conserving solutions. In this paper the conservation of the variance of a scalar property is taken as a simple model for the conservation of kinetic energy. In addition, the derivation and testing of a variance-conserving scheme allows for a clear definition of kinetic energy-conserving advection schemes for solving the Navier-Stokes equations. Consequently, we first derive and test a strictly variance-conserving space-time discretization for the convection term in the convection-diffusion equation. Our starting point is the variance-conserving spatial discretization of the convection operator presented by Piacsek and Williams [J. Comput. Phys. 6 (1970) 392]. In terms of its conservation properties, our variance-conserving scheme is compared to other spatially variance-conserving schemes as well as with the non-variance-conserving schemes applied in our shallow-water solver, see e.g. [Direct and Large-eddy Simulation Workshop IV, ERCOFTAC Series, Kluwer Academic Publishers, 2001, pp. 409-287

Martensitic transformation of type 304 stainless steel by high-energy ion implantation

International Nuclear Information System (INIS)

Chayahara, A.; Satou, M.; Nakashima, S.; Hashimoto, M.; Sasaki, T.; Kurokawa, M.; Kiyama, S.

1991-01-01

The effect of high-energy ion implantation on the structural changes of type 304 stainless steel were investigated. Gold, copper and silicon ions with an energy of 1.5 MeV was implanted into stainless steel. The fluences were in the range from 5x10 15 to 10 17 ions/cm 2 . It was found that the structure of stainless steel was transformed form the austenitic to the martensitic structure by these ion implantations. This structural change was investigated by means of X-ray diffraction and transmission electron microscopy (TEM). The depth profile of the irradiated ions was also analyzed by secondary ion mass spectroscopy (SIMS) and glow discharge spectroscopy (GDS). The degree of martensitic transformation was found to be strongly dependent on the surface pretreatment, either mechanical or electrolytic polishing. When the surface damages or strains by mechanical polishing were present, the martensitic transformation was greatly accelerated presumably due to the combined action of ion irradiation and strain-enhanced transformation. Heavier ions exhibit a high efficiency for the transformation. (orig.)

Energy Management of a Hybrid AC–DC Micro-Grid Based on a Battery Testing System

Directory of Open Access Journals (Sweden)

Bo Long

2015-02-01

Full Text Available Energy Recovery Battery Testing Systems (ERBTS plays an important role in battery manufacture. The conventional ERBTS configuration contains a fundamental transformer, and a bidirectional Direct Current (DC–DC and Alternating Current (AC–DC converter. All ERBTS are connected in parallel, thus constituting a special and complicated AC micro-grid system. Aiming at addressing their low energy recovery efficiency, complex grid-connected control algorithm issues for islanded detection, and complicated power circuit topology issues, a hierarchical DC-link voltage hybrid AC–DC micro-grid that contains composite energy storing devices is proposed. Moreover, an energy management optimal scheme for the proposed scheme is put forward. The system configuration of the proposed scheme is described in detail. Compared to the conventional scheme, the proposed scheme has the merits of simplified power circuit topology, no need for phase synchronous control, and much higher energy recovery efficiency and reliability. The validity and effectiveness of the proposed technique is verified through numerous experimental results.

A new perspective on relativistic transformation for Maxwell's equations of electrodynamics

International Nuclear Information System (INIS)

Huang, Y.-S.

2009-01-01

A new scheme for relativistic transformation of the electromagnetic fields is formulated through relativistic transformation in the wavevector space, instead of the space-time space. Maxwell's equations of electrodynamics are shown to be form-invariant among inertial frames in accordance with this new scheme of relativistic transformation. This new perspective on relativistic transformation not only fulfills the principle of relativity, but is also compatible with quantum theory.

Investigation of switch designs for the dynamic load current multiplier scheme on the SPHYNX microsecond linear transformer driver

International Nuclear Information System (INIS)

Maysonnave, T.; Bayol, F.; Demol, G.; Almeida, T. d'; Lassalle, F.; Morell, A.; Grunenwald, J.; Chuvatin, A.S.; Pecastaing, L.; De Ferron, A.S.

2014-01-01

SPHINX is a microsecond linear transformer driver LTD, used essentially for implosion of Z-pinch loads in direct drive mode. It can deliver a 6-MA current pulse within 800 ns into a Z-pinch load. The dynamic load current multiplier concept enables the current pulse to be modified by increasing its amplitude while reducing its rise time before being delivered to the load. This compact system is made up of concentric electrodes (auto transformer), a dynamic flux extruder (cylindrical wire array), a vacuum convolute (eight post-holes), and a vacuum closing switch, which is the key component of the system. Several different schemes are investigated for designing a vacuum switch suitable for operating the dynamic load current multiplier on the SPHINX generator for various applications, including isentropic compression experiments and Z-pinch radiation effects studies. In particular, the design of a compact vacuum surface switch and a multichannel vacuum switch, located upstream of the load are studied. Electrostatic simulations supporting the switch designs are presented along with test bed experiments. Initial results from shots on the SPHINX driver are also presented. (authors)

Performance investigation on dissipative dielectric elastomer generators with a triangular energy harvesting scheme

Science.gov (United States)

Fan, Peng; Chen, Hualing; Li, Bo; Wang, Yongquan

2017-11-01

In this letter, a theoretical framework describing an energy harvesting cycle including the loss of tension (LT) process is proposed to investigate the energy harvesting performance of a dielectric elastomer generator (DEG) with a triangular energy harvesting scheme by considering material viscosity and leakage current. As the external force that is applied to the membrane decreases, the membrane is relaxed. When the external force decreases to zero, the condition is known as LT. Then the membrane undergoing LT can further relax, which is referred to as the LT process. The LT process is usually ignored in theoretical analysis but observed from energy harvesting experiments of DEGs. It is also studied how shrinking time and transfer capacitor affect the energy conversion of a DEG. The results indicate that energy density and conversion efficiency can be simultaneously improved by choosing appropriate shrinking time and transfer capacitor to optimize the energy harvesting cycle. The results and methods are expected to provide guidelines for the optimal design and assessment of DEGs.

Power transformations improve interpolation of grids for molecular mechanics interaction energies.

Science.gov (United States)

Minh, David D L

2018-02-18

A common strategy for speeding up molecular docking calculations is to precompute nonbonded interaction energies between a receptor molecule and a set of three-dimensional grids. The grids are then interpolated to compute energies for ligand atoms in many different binding poses. Here, I evaluate a smoothing strategy of taking a power transformation of grid point energies and inverse transformation of the result from trilinear interpolation. For molecular docking poses from 85 protein-ligand complexes, this smoothing procedure leads to significant accuracy improvements, including an approximately twofold reduction in the root mean square error at a grid spacing of 0.4 Å and retaining the ability to rank docking poses even at a grid spacing of 0.7 Å. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Incentives for energy efficiency in the EU emission trading scheme

Energy Technology Data Exchange (ETDEWEB)

Schleich, Joachim [Fraunhofer-Institut fuer Systemtechnik und Innovationsforschung (ISI), Karlsruhe (Germany); Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States); Rogge, Karoline [Fraunhofer-Institut fuer Systemtechnik und Innovationsforschung (ISI), Karlsruhe (Germany); ETH Zurich (Switzerland). Group for Sustainability and Technology; Betz, Regina [New South Wales Univ. (Australia). Centre for Energy and Environmental Markets

2008-07-01

This paper explores the incentives for energy efficiency induced by the European Union Emissions Trading Scheme (EU ETS) for installations in the energy and industry sectors. Our analysis of the National Allocation Plans for 27 EU Member States for phase 2 of the EU ETS (2008-2012) suggests that the price and cost effects for improvements in carbon and energy efficiency in the energy and industry sectors will be stronger than in phase 1 (2005-2007), but only because the European Commission has substantially reduced the number of allowances to be allocated by the Member States. To the extent that companies from these sectors (notably power producers) pass through the extra costs for carbon, higher prices for allowances translate into stronger incentives for demand- side energy efficiency. With the cuts in allocation to energy and industry sectors these will be forced to greater reductions, thus the non-ET sectors like household, tertiary and transport will have to reduce less, which is more in line with the cost-efficient share of emission reductions. The findings also imply that domestic efficiency improvements in the energy and industry sectors may remain limited since companies can make substantial use of credits from the Kyoto mechanisms. The analysis of the rules for existing installations, new projects and closures suggests that incentives for energy efficiency are higher in phase 2 than in phase 1 because of the increased application of benchmarking to new and existing installations and because a lower share of allowances will be allocated for free. Nevertheless, there is still ample scope to further improve the EU ETS so that the full potential for energy efficiency can be realized. (orig.)

Symmetric weak ternary quantum homomorphic encryption schemes

Science.gov (United States)

Wang, Yuqi; She, Kun; Luo, Qingbin; Yang, Fan; Zhao, Chao

2016-03-01

Based on a ternary quantum logic circuit, four symmetric weak ternary quantum homomorphic encryption (QHE) schemes were proposed. First, for a one-qutrit rotation gate, a QHE scheme was constructed. Second, in view of the synthesis of a general 3 × 3 unitary transformation, another one-qutrit QHE scheme was proposed. Third, according to the one-qutrit scheme, the two-qutrit QHE scheme about generalized controlled X (GCX(m,n)) gate was constructed and further generalized to the n-qutrit unitary matrix case. Finally, the security of these schemes was analyzed in two respects. It can be concluded that the attacker can correctly guess the encryption key with a maximum probability pk = 1/33n, thus it can better protect the privacy of users’ data. Moreover, these schemes can be well integrated into the future quantum remote server architecture, and thus the computational security of the users’ private quantum information can be well protected in a distributed computing environment.

77 FR 32916 - Energy Conservation Standards for Distribution Transformers: Public Meeting and Availability of...

Science.gov (United States)

2012-06-04

...-2010-BT-STD-0048] RIN 1904-AC04 Energy Conservation Standards for Distribution Transformers: Public... information that it is making available about the liquid-immersed distribution transformer equipment classes... equipment classes for several different types of liquid-immersed distribution transformers. In addition to...

An overview of the EU Member States support schemes for the promotion of renewable energy sources

Energy Technology Data Exchange (ETDEWEB)

Poullikkas, Andreas; Kourtis, George; Hadjipaschalis, Ioannis [Electricity Authority of Cyprus, P.O. Box 24506, 1399 Nicosia (Cyprus)

2012-07-01

In this work, an overview of the European Union (EU) Member States support schemes for the promotion of renewable energy sources (RES) is provided. In particular, the status of the electricity generation capacity as well as the RES mixture in the Member States is described. Moreover, the different support schemes such as, investment support, feed-in tariffs (FiTs), tradable green certificates, and fiscal and financial measures which the Member States have adopted for the promotion of RES technologies are discussed in detail. Some Member States are implementing a single support scheme for the promotion of RES for power generation (RES-E), e.g., seven Member States use FiTs, or implement a hybrid support scheme by combining all or some of the four categories of the RES-E supporting schemes. Although, these support schemes have increased the penetration of the RES-E technologies in the Member States, still there is a long way in order to achieve the 2020 target. The reason for this may be that the way these schemes have been used so far, i.e., either as single support schemes or in combination of FiTs or tradable green certificates with investment support and fiscal and financial measures, has been ineffective. A more effective combination could be a hybrid scheme consisting of FiTs with tradable green certificates measures, as in the case of Italy and United Kingdom, that will increase the RES-E penetration and eliminate the possible technical problems which will arise from this increased penetration and have an effect in the stability of the power system.

The radon transform. Theory and implementation

International Nuclear Information System (INIS)

Toft, P.

1996-01-01

The subject of this Ph.D. thesis is the mathematical Radon transform, which is well suited for curve detection in digital images, and for reconstruction of tomography images. The thesis is divided into two main parts. Part I describes the Radon- and the Hough-transform and especially their discrete approximations with respect to curve parameter detection in digital images. The sampling relationships of the Radon transform is reviewed from a digital signal processing point of view. The discrete Radon transform is investigated for detection of curves, and aspects regarding the performance of the Radon transform assuming various types of noise is covered. Furthermore, a new fast scheme for estimating curve parameters is presented. Part II of the thesis describes the inverse Radon transform in 2D and 3D with focus on reconstruction of tomography images. Some of the direct reconstruction schemes are analyzed, including their discrete implementation. Furthermore, several iterative reconstruction schemes based on linear algebra are reviewed and applied for reconstruction of Positron Emission Tomography (PET) images. A new and very fast implementation of 2D iterative reconstruction methods is devised. In a more practical oriented chapter, the noise in PET images is modelled from a very large number of measurements. Several packagers for Radon- and Hough-transform based curve detection and direct/iterative 2D and 3D reconstruction have been developed and provided for free. (au) 140 refs

New practicable Siberian Snake schemes

International Nuclear Information System (INIS)

Steffen, K.

1983-07-01

Siberian Snake schemes can be inserted in ring accelerators for making the spin tune almost independent of energy. Two such schemes are here suggested which lend particularly well to practical application over a wide energy range. Being composed of horizontal and vertical bending magnets, the proposed snakes are designed to have a small maximum beam excursion in one plane. By applying in this plane a bending correction that varies with energy, they can be operated at fixed geometry in the other plane where most of the bending occurs, thus avoiding complicated magnet motion or excessively large magnet apertures that would otherwise be needed for large energy variations. The first of the proposed schemes employs a pair of standard-type Siberian Snakes, i.e. of the usual 1st and 2nd kind which rotate the spin about the longitudinal and the transverse horizontal axis, respectively. The second scheme employs a pair of novel-type snakes which rotate the spin about either one of the horizontal axes that are at 45 0 to the beam direction. In obvious reference to these axes, they are called left-pointed and right-pointed snakes. (orig.)

Similar goals, divergent motives. The enabling and constraining factors of Russia's capacity-based renewable energy support scheme

International Nuclear Information System (INIS)

Smeets, Niels

2017-01-01

In 2009, the Russian government set its first quantitative renewable energy target at 4.5% of the total electricity produced and consumed by 2020. In 2013, the Government launched its capacity-based renewable energy support scheme (CRESS), however, the expects it will merely add 0.3% to the current 0.67% share of renewables (Ministry of Energy, 2016c). This raises the question what factors might explain this implementation gap. On the basis of field research in Moscow, the article offers an in-depth policy analysis of resource-geographic, financial, institutional and ecologic enabling and constraining factors of Russia's CRESS between 2009 and 2015. To avoid the trap that policy intentions remain on paper, the entire policy cycle – from goal setting to implementation – has been covered. The article concludes that wind energy, which would have contributed the lion's share of new renewable energy capacity, lags behind, jeopardizing the quantitative renewable energy target. The depreciation of the rouble decreased return on investment, and the Local Content Requirement discouraged investors given the lack of Russian wind production facilities. Contrary to resource-geographic and financial expectations, solar projects have been commissioned more accurately, benefitting from access to major business groups and existing production facilities. - Highlights: • The support scheme is focused on the oversupplied integrated electricity market. • The scheme disregards the technical and economic potential in isolated areas. • The solar industry develops at the fastest rate, wind and small hydro lag behind. • Access to business groups and production facilities condition implementation. • The devaluation of the rouble necessitated a revision of the policy design.

Tunable fractional-order Fourier transformer

International Nuclear Information System (INIS)

Malyutin, A A

2006-01-01

A fractional two-dimensional Fourier transformer whose orders are tuned by means of optical quadrupoles is described. It is shown that in the optical scheme considered, the Fourier-transform order a element of [0,1] in one of the mutually orthogonal planes corresponds to the transform order (2-a) in another plane, i.e., to inversion and inverse Fourier transform of the order a. (laser modes and beams)

Travelling Wave Pulse Coupled Oscillator (TWPCO) Using a Self-Organizing Scheme for Energy-Efficient Wireless Sensor Networks.

Science.gov (United States)

Al-Mekhlafi, Zeyad Ghaleb; Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad

2017-01-01

Recently, Pulse Coupled Oscillator (PCO)-based travelling waves have attracted substantial attention by researchers in wireless sensor network (WSN) synchronization. Because WSNs are generally artificial occurrences that mimic natural phenomena, the PCO utilizes firefly synchronization of attracting mating partners for modelling the WSN. However, given that sensor nodes are unable to receive messages while transmitting data packets (due to deafness), the PCO model may not be efficient for sensor network modelling. To overcome this limitation, this paper proposed a new scheme called the Travelling Wave Pulse Coupled Oscillator (TWPCO). For this, the study used a self-organizing scheme for energy-efficient WSNs that adopted travelling wave biologically inspired network systems based on phase locking of the PCO model to counteract deafness. From the simulation, it was found that the proposed TWPCO scheme attained a steady state after a number of cycles. It also showed superior performance compared to other mechanisms, with a reduction in the total energy consumption of 25%. The results showed that the performance improved by 13% in terms of data gathering. Based on the results, the proposed scheme avoids the deafness that occurs in the transmit state in WSNs and increases the data collection throughout the transmission states in WSNs.

Travelling Wave Pulse Coupled Oscillator (TWPCO) Using a Self-Organizing Scheme for Energy-Efficient Wireless Sensor Networks

Science.gov (United States)

Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad

2017-01-01

Recently, Pulse Coupled Oscillator (PCO)-based travelling waves have attracted substantial attention by researchers in wireless sensor network (WSN) synchronization. Because WSNs are generally artificial occurrences that mimic natural phenomena, the PCO utilizes firefly synchronization of attracting mating partners for modelling the WSN. However, given that sensor nodes are unable to receive messages while transmitting data packets (due to deafness), the PCO model may not be efficient for sensor network modelling. To overcome this limitation, this paper proposed a new scheme called the Travelling Wave Pulse Coupled Oscillator (TWPCO). For this, the study used a self-organizing scheme for energy-efficient WSNs that adopted travelling wave biologically inspired network systems based on phase locking of the PCO model to counteract deafness. From the simulation, it was found that the proposed TWPCO scheme attained a steady state after a number of cycles. It also showed superior performance compared to other mechanisms, with a reduction in the total energy consumption of 25%. The results showed that the performance improved by 13% in terms of data gathering. Based on the results, the proposed scheme avoids the deafness that occurs in the transmit state in WSNs and increases the data collection throughout the transmission states in WSNs. PMID:28056020

Pressure correction schemes for compressible flows

International Nuclear Information System (INIS)

Kheriji, W.

2011-01-01

This thesis is concerned with the development of semi-implicit fractional step schemes, for the compressible Navier-Stokes equations; these schemes are part of the class of the pressure correction methods. The chosen spatial discretization is staggered: non conforming mixed finite elements (Crouzeix-Raviart or Rannacher-Turek) or the classic MA C scheme. An upwind finite volume discretization of the mass balance guarantees the positivity of the density. The positivity of the internal energy is obtained by discretizing the internal energy balance by an upwind finite volume scheme and b y coupling the discrete internal energy balance with the pressure correction step. A special finite volume discretization on dual cells is performed for the convection term in the momentum balance equation, and a renormalisation step for the pressure is added to the algorithm; this ensures the control in time of the integral of the total energy over the domain. All these a priori estimates imply the existence of a discrete solution by a topological degree argument. The application of this scheme to Euler equations raises an additional difficulty. Indeed, obtaining correct shocks requires the scheme to be consistent with the total energy balance, property which we obtain as follows. First of all, a local discrete kinetic energy balance is established; it contains source terms winch we somehow compensate in the internal energy balance. The kinetic and internal energy equations are associated with the dual and primal meshes respectively, and thus cannot be added to obtain a total energy balance; its continuous counterpart is however recovered at the limit: if we suppose that a sequence of discrete solutions converges when the space and time steps tend to 0, we indeed show, in 1D at least, that the limit satisfies a weak form of the equation. These theoretical results are comforted by numerical tests. Similar results are obtained for the baro-tropic Navier-Stokes equations. (author)

A fully discrete energy stable scheme for a phase filed moving contact line model with variable densities and viscosities

KAUST Repository

Zhu, Guangpu

2018-01-26

In this paper, a fully discrete scheme which considers temporal and spatial discretizations is presented for the coupled Cahn-Hilliard equation in conserved form with the dynamic contact line condition and the Navier-Stokes equation with the generalized Navier boundary condition. Variable densities and viscosities are incorporated in this model. A rigorous proof of energy stability is provided for the fully discrete scheme based on a semi-implicit temporal discretization and a finite difference method on the staggered grids for the spatial discretization. A splitting method based on the pressure stabilization is implemented to solve the Navier-Stokes equation, while the stabilization approach is also used for the Cahn-Hilliard equation. Numerical results in both 2-D and 3-D demonstrate the accuracy, efficiency and decaying property of discrete energy of the proposed scheme.

Development of the Latvian scheme for energy auditing of buildings and inspection of boilers and air-conditioning systems. Final report institutional set-up

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-12-01

To implement EU directive 93/76/EEC on reduction of carbon dioxide emission by increasing energy efficiency and EU directive 2002/91/EC on building energy efficiency, Latvia must establish and institutional scheme and define all the organisations involved. From a general perspective the institutional scheme must as a minimum include the following four key players: the administrator, the operating unit, the auditors or independent experts, and finally the client. Furthermore, institutions dealing with financing of energy efficiency improvement activities, training and certification of experts, information about auditing and energy efficiency etc. need to be involved. At present there is no governmental or private Latvian organisation that could fully rearrange and assume the duties of an energy audit scheme secretariat. It is therefore recommended initially to place the secretariat as a separate, new unit within the Ministry of Economy, financed by the Ministry of Economy, with the intention of establishing at a later stage (after e.g. 5 years) a separate, new agency, an Energy Efficiency Agency partly financed by the incomes from the energy audit and boiler inspection schemes. The Secretariat should, both in its initial phase and later, assign the tasks of training, information campaigns, quality assurance and evaluation to external organisations. (BA)

A Spatial Domain Quantum Watermarking Scheme

International Nuclear Information System (INIS)

Wei Zhan-Hong; Chen Xiu-Bo; Niu Xin-Xin; Yang Yi-Xian; Xu Shu-Jiang

2016-01-01

This paper presents a spatial domain quantum watermarking scheme. For a quantum watermarking scheme, a feasible quantum circuit is a key to achieve it. This paper gives a feasible quantum circuit for the presented scheme. In order to give the quantum circuit, a new quantum multi-control rotation gate, which can be achieved with quantum basic gates, is designed. With this quantum circuit, our scheme can arbitrarily control the embedding position of watermark images on carrier images with the aid of auxiliary qubits. Besides reversely acting the given quantum circuit, the paper gives another watermark extracting algorithm based on quantum measurements. Moreover, this paper also gives a new quantum image scrambling method and its quantum circuit. Differ from other quantum watermarking schemes, all given quantum circuits can be implemented with basic quantum gates. Moreover, the scheme is a spatial domain watermarking scheme, and is not based on any transform algorithm on quantum images. Meanwhile, it can make sure the watermark be secure even though the watermark has been found. With the given quantum circuit, this paper implements simulation experiments for the presented scheme. The experimental result shows that the scheme does well in the visual quality and the embedding capacity. (paper)

Energy band structure of Cr by the Slater-Koster interpolation scheme

International Nuclear Information System (INIS)

Seifu, D.; Mikusik, P.

1986-04-01

The matrix elements of the Hamiltonian between nine localized wave-functions in tight-binding formalism are derived. The symmetry adapted wave-functions and the secular equations are formed by the group theory method for high symmetry points in the Brillouin zone. A set of interaction integrals is chosen on physical ground and fitted via the Slater-Koster interpolation scheme to the abinito band structure of chromium calculated by the Green function method. Then the energy band structure of chromium is interpolated and extrapolated in the Brillouin zone. (author)

Limited-angle three-dimensional reconstructions using Fourier transform iterations and Radon transform iterations

International Nuclear Information System (INIS)

Tam, K.C.; Perez-Mendez, V.

1981-01-01

The principles of limited-angle reconstruction of space-limited objects using the concepts of allowed cone and missing cone in Fourier space are discussed. The distortion of a point source resulting from setting the Fourier components in the missing cone to zero has been calculated mathematically, and its bearing on the convergence of an iteration scheme involving Fourier transforms has been analyzed in detail. it was found that the convergence rate is fairly insensitive to the position of the point source within the boundary of the object, apart from an edge effect which tends to enhance some parts of the boundary in reconstructing the object. Another iteration scheme involving Radon transforms was introduced and compared to the Fourier transform method in such areas as root mean square error, stability with respect to noise, and computer reconstruction time

Limited-angle 3-D reconstructions using Fourier transform iterations and Radon transform iterations

International Nuclear Information System (INIS)

Tam, K.C.; Perez-Mendez, V.

1979-12-01

The principles of limited-angle reconstruction of space-limited objects using the concepts of allowed cone and missing cone in Fourier space are discussed. The distortion of a point source resulting from setting the Fourier components in the missing cone to zero was calculated mathematically, and its bearing on the convergence of an iteration scheme involving Fourier transforms was analyzed in detail. It was found that the convergence rate is fairly insensitive to the position of the point source within the boundary of the object, apart from an edge effect that tends to enhance some parts of the boundary in reconstructing the object. Another iteration scheme involving Radon transforms was introduced and compared to the Fourier transform method in such areas as root mean square error, stability with respect to noise, and computer reconstruction time. 8 figures, 2 tables

An encryption scheme based on phase-shifting digital holography and amplitude-phase disturbance

International Nuclear Information System (INIS)

Hua Li-Li; Xu Ning; Yang Geng

2014-01-01

In this paper, we propose an encryption scheme based on phase-shifting digital interferometry. According to the original system framework, we add a random amplitude mask and replace the Fourier transform by the Fresnel transform. We develop a mathematical model and give a discrete formula based on the scheme, which makes it easy to implement the scheme in computer programming. The experimental results show that the improved system has a better performance in security than the original encryption method. Moreover, it demonstrates a good capability of anti-noise and anti-shear robustness

Advanced Energy Harvesting Control Schemes for Marine Renewable Energy Devices

Energy Technology Data Exchange (ETDEWEB)

McEntee, Jarlath [Ocean Renewable Power Company, Portland, ME (United States); Polagye, Brian [Ocean Renewable Power Company, Portland, ME (United States); Fabien, Brian [Ocean Renewable Power Company, Portland, ME (United States); Thomson, Jim [Ocean Renewable Power Company, Portland, ME (United States); Kilcher, Levi [Ocean Renewable Power Company, Portland, ME (United States); Marnagh, Cian [Ocean Renewable Power Company, Portland, ME (United States); Donegan, James [Ocean Renewable Power Company, Portland, ME (United States)

2016-03-31

The Advanced Energy Harvesting Control Schemes for Marine Renewable Energy Devices (Project) investigated, analyzed and modeled advanced turbine control schemes with the objective of increasing the energy harvested by hydrokinetic turbines in turbulent flow. Ocean Renewable Power Company (ORPC) implemented and validated a feedforward controller to increase power capture; and applied and tested the controls on ORPC’s RivGen® Power Systems in Igiugig, Alaska. Assessments of performance improvements were made for the RivGen® in the Igiugig environment and for ORPC’s TidGen® Power System in a reference tidal environment. Annualized Energy Production (AEP) and Levelized Cost of Energy (LCOE) improvements associated with implementation of the recommended control methodology were made for the TidGen® Power System in the DOE reference tidal environment. System Performance Advancement (SPA) goals were selected for the project. SPA targets were to improve Power to Weight Ratio (PWR) and system Availability, with the intention of reducing Levelized Cost of Electricity (LCOE). This project focused primarily reducing in PWR. Reductions in PWR of 25.5% were achieved. Reductions of 20.3% in LCOE were achieved. This project evaluated four types of controllers which were tested in simulation, emulation, a laboratory flume, and the field. The adaptive Kω2 controller performs similarly to the non-adaptive version of the same controller and may be useful in tidal channels where the mean velocity is continually evolving. Trends in simulation were largely verified through experiments, which also provided the opportunity to test assumptions about turbine responsiveness and control resilience to varying scales of turbulence. Laboratory experiments provided an essential stepping stone between simulation and implementation on a field-scale turbine. Experiments also demonstrated that using “energy loss” as a metric to differentiate between well-designed controllers operating at

Environmental assessment of alternative treatment schemes for energy and nutrient recovery from livestock manure.

Science.gov (United States)

Pedizzi, C; Noya, I; Sarli, J; González-García, S; Lema, J M; Moreira, M T; Carballa, M

2018-04-20

The application of livestock manure on agricultural land is being restricted due to its significant content of phosphorus (P) and nitrogen (N), leading to eutrophication. At the same time, the growing demand for N and P mineral fertilizers is increasing their production costs and causing the depletion of natural phosphate rock deposits. In the present work, seven technologically feasible treatment schemes for energy (biogas) and nutrient recovery (e.g., struvite precipitation) and/or removal (e.g., partial nitritation/anammox) were evaluated from an environmental perspective. In general, while approaches based solely on energy recovery and use of digestate as fertilizer are commonly limited by community regulations, strategies pursuing the generation of high-quality struvite are not environmentally sound alternatives. In contrast, schemes that include further solid/liquid separation of the digestate improved the environmental profile, and their combination with an additional N-removal stage would lead to the most environmental-friendly framework. However, the preferred scenario was identified to be highly dependent on the particular conditions of each site, integrating environmental, social and economic criteria. Copyright © 2018 Elsevier Ltd. All rights reserved.

Flux and transformation of the solar wind energy in the magnetosheath of the magnetosphere

International Nuclear Information System (INIS)

Pudovkin, M.I.; Semenov, V.S.

1986-01-01

Energy flux, incoming from the solar wind to the Earth magnetosphere is calculated. It is shown that Poynting vector flux, incoming to the reconnection area is generated mainly in the transitional area between the departed shock wave front and magnetopause in the result of the retardation of the solar wind and partial transformation of its kinetic energy into magnetic one. In this case the energy transformation coefficient depends on the interplanetary magnetic field intensity. Solar wind energy gets into the area of magnetic field reconnection at the magnetopause mainly in two forms: electromagnetic and thermal energy. In the course of reconnection process magnetic energy converts into kinetic energy of the accelerated plasma mass movement and subsequently turns (in a high-latitude boundary layer) into electromagnetic energy, incoming directly to magnetosphere tail

Integrable lattices and their sublattices: From the discrete Moutard (discrete Cauchy-Riemann) 4-point equation to the self-adjoint 5-point scheme

International Nuclear Information System (INIS)

Doliwa, A.; Grinevich, P.; Nieszporski, M.; Santini, P. M.

2007-01-01

We present the sublattice approach, a procedure to generate, from a given integrable lattice, a sublattice which inherits its integrability features. We consider, as illustrative example of this approach, the discrete Moutard 4-point equation and its sublattice, the self-adjoint 5-point scheme on the star of the square lattice, which are relevant in the theory of the integrable discrete geometries and in the theory of discrete holomorphic and harmonic functions (in this last context, the discrete Moutard equation is called discrete Cauchy-Riemann equation). Therefore an integrable, at one energy, discretization of elliptic two-dimensional operators is considered. We use the sublattice point of view to derive, from the Darboux transformations and superposition formulas of the discrete Moutard equation, the Darboux transformations and superposition formulas of the self-adjoint 5-point scheme. We also construct, from algebro-geometric solutions of the discrete Moutard equation, algebro-geometric solutions of the self-adjoint 5-point scheme. In particular, we show that the corresponding restrictions on the finite-gap data are of the same type as those for the fixed energy problem for the two-dimensional Schroedinger operator. We finally use these solutions to construct explicit examples of discrete holomorphic and harmonic functions, as well as examples of quadrilateral surfaces in R 3

Transition without Conflict? Renewable Energy Initiatives in the Dutch Energy Transition

Directory of Open Access Journals (Sweden)

Antonia Proka

2018-05-01

Full Text Available In the context of the slowly progressing energy transition, a number of renewable energy initiatives have been emerging in the Netherlands. These initiatives represent alternatives to the dominant functioning of the energy system, and as such, may come into conflict with it. Transitions involve system destabilisation and conflict between the incumbent regime and the initiatives originating in niches. In order to assess the transformative potential of such initiatives, this paper addresses the question: what kind of conflicts and tensions arise from renewable energy initiatives, and what strategies do they develop to overcome or avoid them? Combined with a business model perspective, transition thinking enabled a better understanding of how the initiatives organise themselves, and where the points of friction with their institutional context emerge. We suggest that the instances of conflict may function as an indication for the state of the energy transition and the transformative potential impact of such initiatives. The instances discussed in this contribution relate to existing support schemes, technology choices, and the overall organisational networks of the emerging sector.

Finite element evaluation of elasto-plastic accommodation energies during solid state transformations: Coherent, spherical precipitate in finite matrix

International Nuclear Information System (INIS)

Sen, S.; Balasubramaniam, R.; Sethuraman, R.

1996-01-01

The molar volume difference between the matrix and the precipitate phases in the case of solid state phase transformations results in the creation of stain energy in the system due to the misfit strains. A finite element model based on the initial strain approach is proposed to evaluate elasto-plastic accommodation energies during solid state transformation. The three-dimensional axisymmetric model has been used to evaluate energies as a function of transformation for α-β hydrogen transformations in the Nb-H system. The transformation has been analyzed for the cases of transformation progressing both from the center to surface and from the surface to center of the system. The effect of plastic deformation has been introduced to make the model realistic, specifically to the Nb-NbH phase transformation which involves a 4% linear misfit strain. It has been observed that plastic deformation reduces the strain energies compared to the linear elastic analysis

Nonlinear Effects in Transformation Optics-Based Metamaterial Shields for Counter Directed Energy Weapon Defense

Science.gov (United States)

2016-06-01

employs the in- variance of the Maxwell equations under coordinate transformations to convert the free- space wave solutions in a coordinate... ENERGY WEAPON DEFENSE by Jacob D. Thompson June 2016 Thesis Co-Advisors: James Luscombe Brett Borden Approved for public release; distribution is...2014 to 06-17-2016 4. TITLE AND SUBTITLE NONLINEAR EFFECTS IN TRANSFORMATION OPTICS-BASED METAMATE- RIAL SHIELDS FOR COUNTER DIRECTED ENERGY WEAPON

Overview of renewable energies during the first six-month period of 2013. Wind energy, Photovoltaic energy, Connection schemes (S3REnR)

International Nuclear Information System (INIS)

2013-01-01

Illustrated by maps, graphs and tables, the first part of this document presents and comments data related to wind energy production. It addresses the status of the wind energy production stock (connected stock in June 2013, regional distribution, distribution in terms of power range, evolution of wind turbine and wind farm power), growth perspectives, and the role of wind energy production in the supply-demand balance (production and load factor, regional distribution of production and load factor, share in consumption coverage, wind energy production flow management). Using the same kind of presentation and the same issues, the second part presents and comments data related to photovoltaic energy production in France: photovoltaic stock (connected stock in June 2013, regional distribution, distribution in terms of power range), growth perspectives, and role of photovoltaic energy production in the supply-demand balance (production and load factor, production and load factor regional distribution, role in consumption coverage). The third part briefly presents data related to Regional Schemes of Connection to the renewable energy network (S3REnR) which ensure conditions of connection to the electric grid of all renewable energies

Exact Throughput Analyses of Energy-Harvesting Cooperation Scheme with Best Relay Selections Under I/Q Imbalance

Directory of Open Access Journals (Sweden)

Tan Phuoc Huynh

2017-01-01

Full Text Available In this paper, we propose an energy-harvesting cooperation scheme in which relays suffer in-phase and quadrature-phase imbalances (IQI and harvest energy from a wireless transmit source. A best relay is selected based on end-to-end signal-to-interference-plus-noise ratios (SINRs in both Amplify-and-Forward (called an EHAF protocol and Decode-and-Forward (called an EHDF protocol cooperation methods. We analyze and evaluate the system performance in terms of exact closed-form throughputs over Rayleigh fading channels. Simulation and analysis results discover contributions as follows. Firstly, the throughput performance of the proposed protocols EHAF and EHDF is improved when comparing with that of a non-selection cooperation scheme. Secondly, the EHDF protocol is more efficient than the EHAF protocol. Finally, the theoretical analyses are validated by performing Monte Carlo simulations.

Quantization Distortion in Block Transform-Compressed Data

Science.gov (United States)

Boden, A. F.

1995-01-01

The popular JPEG image compression standard is an example of a block transform-based compression scheme; the image is systematically subdivided into block that are individually transformed, quantized, and encoded. The compression is achieved by quantizing the transformed data, reducing the data entropy and thus facilitating efficient encoding. A generic block transform model is introduced.

The parallel algorithm for the 2D discrete wavelet transform

Science.gov (United States)

Barina, David; Najman, Pavel; Kleparnik, Petr; Kula, Michal; Zemcik, Pavel

2018-04-01

The discrete wavelet transform can be found at the heart of many image-processing algorithms. Until now, the transform on general-purpose processors (CPUs) was mostly computed using a separable lifting scheme. As the lifting scheme consists of a small number of operations, it is preferred for processing using single-core CPUs. However, considering a parallel processing using multi-core processors, this scheme is inappropriate due to a large number of steps. On such architectures, the number of steps corresponds to the number of points that represent the exchange of data. Consequently, these points often form a performance bottleneck. Our approach appropriately rearranges calculations inside the transform, and thereby reduces the number of steps. In other words, we propose a new scheme that is friendly to parallel environments. When evaluating on multi-core CPUs, we consistently overcome the original lifting scheme. The evaluation was performed on 61-core Intel Xeon Phi and 8-core Intel Xeon processors.

A Novel Three Phase to Seven Phase Conversion Technique Using Transformer Winding Connections

Directory of Open Access Journals (Sweden)

M. Tabrez

2017-10-01

Full Text Available This paper proposes a novel multiphase transformer connection scheme which converts three phase balanced AC input to seven phase balanced AC output. Generalized theory to convert a three phase utility supply into any number of phases is presented. Based on the proposed generalized principle, a three phase to seven phase power converting transformer design is presented with connection scheme, analysis and simulation and experimental results of the proposed three phase to seven phase conversion transformer. The proposed transformer in this paper is analyzed and compared with the connection scheme for seven phase available in the literature. The connection scheme is found to have higher power density, lower core area and lower core requirement as compared to the available connection scheme of the same rating. Impedance mismatching between different phases of the transformer is observed in the three phase to seven phase transformer available in the literature. As this mismatching introduces error in study of per phase equivalent circuit diagrams as well as imbalance in voltage and currents. The present design also addresses the impedance mismatching issue and reduces mismatching in the proposed transformer design. A prototype of the proposed system is developed and waveforms are presented. The proposed design is verified using simulation and validated using experimental approach.

A New Battery Energy Storage Charging/Discharging Scheme for Wind Power Producers in Real-Time Markets

Directory of Open Access Journals (Sweden)

Minh Y Nguyen

2012-12-01

Full Text Available Under a deregulated environment, wind power producers are subject to many regulation costs due to the intermittence of natural resources and the accuracy limits of existing prediction tools. This paper addresses the operation (charging/discharging problem of battery energy storage installed in a wind generation system in order to improve the value of wind power in the real-time market. Depending on the prediction of market prices and the probabilistic information of wind generation, wind power producers can schedule the battery energy storage for the next day in order to maximize the profit. In addition, by taking into account the expenses of using batteries, the proposed charging/discharging scheme is able to avoid the detrimental operation of battery energy storage which can lead to a significant reduction of battery lifetime, i.e., uneconomical operation. The problem is formulated in a dynamic programming framework and solved by a dynamic programming backward algorithm. The proposed scheme is then applied to the study cases, and the results of simulation show its effectiveness.

Application of a Laplace transform pair model for high-energy x-ray spectral reconstruction.

Science.gov (United States)

Archer, B R; Almond, P R; Wagner, L K

1985-01-01

A Laplace transform pair model, previously shown to accurately reconstruct x-ray spectra at diagnostic energies, has been applied to megavoltage energy beams. The inverse Laplace transforms of 2-, 6-, and 25-MV attenuation curves were evaluated to determine the energy spectra of these beams. The 2-MV data indicate that the model can reliably reconstruct spectra in the low megavoltage range. Experimental limitations in acquiring the 6-MV transmission data demonstrate the sensitivity of the model to systematic experimental error. The 25-MV data result in a physically realistic approximation of the present spectrum.

Full wave dc-to-dc converter using energy storage transformers

Science.gov (United States)

Moore, E. T.; Wilson, T. G.

1969-01-01

Full wave dc-to-dc converter, for an ion thrustor, uses energy storage transformers to provide a method of dc-to-dc conversion and regulation. The converter has a high degree of physical simplicity, is lightweight and has high efficiency.

An improved experimental scheme for simultaneous measurement of high-resolution zero electron kinetic energy (ZEKE) photoelectron and threshold photoion (MATI) spectra

Science.gov (United States)

Michels, François; Mazzoni, Federico; Becucci, Maurizio; Müller-Dethlefs, Klaus

2017-10-01

An improved detection scheme is presented for threshold ionization spectroscopy with simultaneous recording of the Zero Electron Kinetic Energy (ZEKE) and Mass Analysed Threshold Ionisation (MATI) signals. The objective is to obtain accurate dissociation energies for larger molecular clusters by simultaneously detecting the fragment and parent ion MATI signals with identical transmission. The scheme preserves an optimal ZEKE spectral resolution together with excellent separation of the spontaneous ion and MATI signals in the time-of-flight mass spectrum. The resulting improvement in sensitivity will allow for the determination of dissociation energies in clusters with substantial mass difference between parent and daughter ions.

A Scheme for Initial Exploratory Data Analysis of Multivariate Image Data

DEFF Research Database (Denmark)

Hilger, Klaus Baggesen; Nielsen, Allan Aasbjerg; Larsen, Rasmus

2001-01-01

A new scheme is proposed for handling initial exploratory analyses of multivariate image data. The method is invariant to linear transformations of the original data and is useful for data fusion of multisource measurements. The scheme includes dimensionality reduction followed by unsupervised...... clustering of the data. A transformation is proposed which maximizes autocorrelation by projection onto subspaces with signal-to-noise ratio dependent variance. We apply the traditional fuzzy c-means algorithm and introduce two additional memberships enhancing the textural awareness of the algorithm. Cluster...

Oncogenic transformation in C3H10T1/2 cells by low-energy neutrons.

Science.gov (United States)

Miller, R C; Marino, S A; Napoli, J; Shah, H; Hall, E J; Geard, C R; Brenner, D J

2000-03-01

Occupational exposure to neutrons typically includes significant doses of low-energy neutrons, with energies below 100 keV. In addition, the normal-tissue dose from boron neutron capture therapy will largely be from low-energy neutrons. Microdosimetric theory predicts decreasing biological effectiveness for neutrons with energies below about 350 keV compared with that for higher-energy neutrons; based on such considerations, and limited biological data, the current radiation weighting factor (quality factor) for neutrons with energies from 10 keV to 100 keV is less than that for higher-energy neutrons. By contrast, some reports have suggested that the biological effectiveness of low-energy neutrons is similar to that of fast neutrons. The purpose of the current work is to assess the relative biological effectiveness of low-energy neutrons for an endpoint of relevance to carcinogenesis: in vitro oncogenic transformation. Oncogenic transformation induction frequencies were determined for C3H10T1/2 cells exposed to two low-energy neutron beams, respectively, with dose-averaged energies of 40 and 70 keV, and the results were compared with those for higher-energy neutrons and X-rays. These results for oncogenic transformation provide evidence for a significant decrease in biological effectiveness for 40 keV neutrons compared with 350 keV neutrons. The 70 keV neutrons were intermediate in effectiveness between the 70 and 350 keV beams. A decrease in biological effectiveness for low-energy neutrons is in agreement with most (but not all) earlier biological studies, as well as microdosimetric considerations. The results for oncogenic transformation were consistent with the currently recommended decreased values for low-energy neutron radiation weighting factors compared with fast neutrons.

Energy Balance Routing Algorithm Based on Virtual MIMO Scheme for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Jianpo Li

2014-01-01

Full Text Available Wireless sensor networks are usually energy limited and therefore an energy-efficient routing algorithm is desired for prolonging the network lifetime. In this paper, we propose a new energy balance routing algorithm which has the following three improvements over the conventional LEACH algorithm. Firstly, we propose a new cluster head selection scheme by taking into consideration the remaining energy and the most recent energy consumption of the nodes and the entire network. In this way, the sensor nodes with smaller remaining energy or larger energy consumption will be much less likely to be chosen as cluster heads. Secondly, according to the ratio of remaining energy to distance, cooperative nodes are selected to form virtual MIMO structures. It mitigates the uneven distribution of clusters and the unbalanced energy consumption of the whole network. Thirdly, we construct a comprehensive energy consumption model, which can reflect more realistically the practical energy consumption. Numerical simulations analyze the influences of cooperative node numbers and cluster head node numbers on the network lifetime. It is shown that the energy consumption of the proposed routing algorithm is lower than the conventional LEACH algorithm and for the simulation example the network lifetime is prolonged about 25%.

A hybrid energy-economy model for global integrated assessment of climate change, carbon mitigation and energy transformation

International Nuclear Information System (INIS)

Cai, Yiyong; Newth, David; Finnigan, John; Gunasekera, Don

2015-01-01

Highlights: • This paper introduces the design of a hybrid energy-economy model, GTEM-C. • The model offers a unified tool to analyse the energy-carbon-environment nexus. • Results are presented on global energy transformation due to carbon mitigation. • Electrification with renewable energies can contain the spiking of carbon prices. - Abstract: This paper introduces the design of the CSIRO variant of the Global Trade and Environment model (GTEM-C). GTEM-C is a hybrid model that combines the top-down macroeconomic representation of a computable general equilibrium model with the bottom-up engineering details of energy production. The model features detailed accounting for global energy flows that are embedded in traded energy goods, and it offers a unified framework to analyse the energy-carbon-environment nexus. As an illustrative example, we present simulation results on global energy transformation under the Intergovernmental Panel on Climate Change’s representative carbon pathways 4.5 and 8.5. By testing the model’s sensitivity to the relevant parameter, we find that the pace of electrification will significantly contain the spiking of carbon prices because electricity can be produced from carbon-free or less carbon-intensive technologies. The decoupling of energy use and carbon footprint, due to the uptake of clean electricity technologies, such as nuclear, wind, solar, and carbon capture and storage, allows the world to maintain high level of energy consumption, which is essential to economic growth

Energy Efficiency and SINR Maximization Beamformers for Spectrum Sharing With Sensing Information

KAUST Repository

Alabbasi, Abdulrahman

2014-09-01

In this paper, we consider a cognitive radio multi-input-multi-output environment, in which we adapt our beamformer to maximize both energy efficiency (EE) and signal-to-interference-plus-noise ratio (SINR) metrics. Our design considers an underlaying communication using adaptive beamforming schemes combined with sensing information to achieve optimal energy-efficient systems. The proposed schemes maximize EE and SINR metrics subject to cognitive radio and quality-of-service constraints. The analysis of the proposed schemes is classified into two categories based on knowledge of the secondary-transmitter-to-primary-receiver channel. Since the optimizations of EE and SINR problems are not convex problems, we transform them into a standard semidefinite programming (SDP) form to guarantee that the optimal solutions are global. An analytical solution is provided for one scheme, while the second scheme is left in a standard SDP form. Selected numerical results are used to quantify the impact of the sensing information on the proposed schemes compared to the benchmark ones.

Economic scheme for remote preparation of an arbitrary five-qubit ...

Indian Academy of Sciences (India)

advantage of the present scheme is that the entanglement resource can be reduced ... tanglement is also a very important physical resource in quantum information processing. .... on the qubit B3, and thus the state (10) will be transformed into ... Hence, we claim our scheme is feasible according to current technologies, and.

Girsanov's transformation based variance reduced Monte Carlo simulation schemes for reliability estimation in nonlinear stochastic dynamics

Energy Technology Data Exchange (ETDEWEB)

Kanjilal, Oindrila, E-mail: oindrila@civil.iisc.ernet.in; Manohar, C.S., E-mail: manohar@civil.iisc.ernet.in

2017-07-15

The study considers the problem of simulation based time variant reliability analysis of nonlinear randomly excited dynamical systems. Attention is focused on importance sampling strategies based on the application of Girsanov's transformation method. Controls which minimize the distance function, as in the first order reliability method (FORM), are shown to minimize a bound on the sampling variance of the estimator for the probability of failure. Two schemes based on the application of calculus of variations for selecting control signals are proposed: the first obtains the control force as the solution of a two-point nonlinear boundary value problem, and, the second explores the application of the Volterra series in characterizing the controls. The relative merits of these schemes, vis-à-vis the method based on ideas from the FORM, are discussed. Illustrative examples, involving archetypal single degree of freedom (dof) nonlinear oscillators, and a multi-degree of freedom nonlinear dynamical system, are presented. The credentials of the proposed procedures are established by comparing the solutions with pertinent results from direct Monte Carlo simulations. - Highlights: • The distance minimizing control forces minimize a bound on the sampling variance. • Establishing Girsanov controls via solution of a two-point boundary value problem. • Girsanov controls via Volterra's series representation for the transfer functions.

Combining feed-in tariffs and net-metering schemes to balance development in adoption of photovoltaic energy: Comparative economic assessment and policy implications for European countries

International Nuclear Information System (INIS)

Ramírez, F. Javier; Honrubia-Escribano, A.; Gómez-Lázaro, E.; Pham, Duc T.

2017-01-01

In the last fifteen years, Europe has been involved in the major development of photovoltaic (PV) solar energy. The Kyoto Protocol requirements and the European Union (EU) directives to promote the use of renewable energy sources (RES) together with environmental policies introduced for the development and use of alternative energies have generated a large number of market opportunities for this sector. Differences in the application of energy policies have caused significant imbalances in electricity systems and distortion of electricity prices. The main concern of governments is to define the support schemes to be used and how to combine them in the most profitable manner. The aim of this paper is to provide a comparative cost-effectiveness assessment using feed-in tariffs (FiT) and net-metering (NM) schemes in some representative EU countries. The authors have developed an economic model to evaluate the profitability of PV projects combining these support schemes. Results show not only the circumstances under which solar energy is economically profitable, but also the kind of PV systems, locations, minimum levels of tariff prices and specific combination of support schemes that should be promoted. - Highlights: • Comparative cost-effectiveness assessment combining FiT and NM support schemes. • A minimum FiT is proposed in addition to traditional financial performance indicators. • Results show the specific combinations of support schemes that should be promoted. • This work can aid efficient energy policy making. • Model could be applied to other types of RES projects and other geographical areas.

Spatial eigensolution analysis of energy-stable flux reconstruction schemes and influence of the numerical flux on accuracy and robustness

Science.gov (United States)

Mengaldo, Gianmarco; De Grazia, Daniele; Moura, Rodrigo C.; Sherwin, Spencer J.

2018-04-01

This study focuses on the dispersion and diffusion characteristics of high-order energy-stable flux reconstruction (ESFR) schemes via the spatial eigensolution analysis framework proposed in [1]. The analysis is performed for five ESFR schemes, where the parameter 'c' dictating the properties of the specific scheme recovered is chosen such that it spans the entire class of ESFR methods, also referred to as VCJH schemes, proposed in [2]. In particular, we used five values of 'c', two that correspond to its lower and upper bounds and the others that identify three schemes that are linked to common high-order methods, namely the ESFR recovering two versions of discontinuous Galerkin methods and one recovering the spectral difference scheme. The performance of each scheme is assessed when using different numerical intercell fluxes (e.g. different levels of upwinding), ranging from "under-" to "over-upwinding". In contrast to the more common temporal analysis, the spatial eigensolution analysis framework adopted here allows one to grasp crucial insights into the diffusion and dispersion properties of FR schemes for problems involving non-periodic boundary conditions, typically found in open-flow problems, including turbulence, unsteady aerodynamics and aeroacoustics.

Helicity and evanescent waves. [Energy transport velocity, helicity, Lorentz transformation

Energy Technology Data Exchange (ETDEWEB)

Agudin, J L; Platzeck, A M [La Plata Univ. Nacional (Argentina); Albano, J R [Instituto de Astronomia y Fisica del Espacio, Buenos Aires, Argentina

1978-02-20

It is shown that the projection of the angular momentum of a circularly polarized electromagnetic evanescent wave along the mean velocity of energy transport (=helicity) can be reverted by a Lorentz transformation, in spite of the fact that this velocity is c.

An Implicit Scheme of Lattice Boltzmann Method for Sine-Gordon Equation

International Nuclear Information System (INIS)

Hui-Lin, Lai; Chang-Feng, Ma

2008-01-01

We establish an implicit scheme of lattice Boltzmann method for simulating the sine-Gordon equation, which can be transformed into the explicit one, so the computation of the scheme is simple. Moreover, the parameter θ of the implicit scheme is independent of the relaxation time, which makes the model more flexible. The numerical results show that this method is very effective. (fundamental areas of phenomenology (including applications))

Impact of the snow cover scheme on snow distribution and energy budget modeling over the Tibetan Plateau

Science.gov (United States)

Xie, Zhipeng; Hu, Zeyong; Xie, Zhenghui; Jia, Binghao; Sun, Genhou; Du, Yizhen; Song, Haiqing

2018-02-01

This paper presents the impact of two snow cover schemes (NY07 and SL12) in the Community Land Model version 4.5 (CLM4.5) on the snow distribution and surface energy budget over the Tibetan Plateau. The simulated snow cover fraction (SCF), snow depth, and snow cover days were evaluated against in situ snow depth observations and a satellite-based snow cover product and snow depth dataset. The results show that the SL12 scheme, which considers snow accumulation and snowmelt processes separately, has a higher overall accuracy (81.8%) than the NY07 (75.8%). The newer scheme performs better in the prediction of overall accuracy compared with the NY07; however, SL12 yields a 15.1% underestimation rate while NY07 overestimated the SCF with a 15.2% overestimation rate. Both two schemes capture the distribution of the maximum snow depth well but show large positive biases in the average value through all periods (3.37, 3.15, and 1.48 cm for NY07; 3.91, 3.52, and 1.17 cm for SL12) and overestimate snow cover days compared with the satellite-based product and in situ observations. Higher altitudes show larger root-mean-square errors (RMSEs) in the simulations of snow depth and snow cover days during the snow-free period. Moreover, the surface energy flux estimations from the SL12 scheme are generally superior to the simulation from NY07 when evaluated against ground-based observations, in particular for net radiation and sensible heat flux. This study has great implications for further improvement of the subgrid-scale snow variations over the Tibetan Plateau.

A no-key-exchange secure image sharing scheme based on Shamir's three-pass cryptography protocol and the multiple-parameter fractional Fourier transform.

Science.gov (United States)

Lang, Jun

2012-01-30

In this paper, we propose a novel secure image sharing scheme based on Shamir's three-pass protocol and the multiple-parameter fractional Fourier transform (MPFRFT), which can safely exchange information with no advance distribution of either secret keys or public keys between users. The image is encrypted directly by the MPFRFT spectrum without the use of phase keys, and information can be shared by transmitting the encrypted image (or message) three times between users. Numerical simulation results are given to verify the performance of the proposed algorithm.

A Potential Issue Involving the Application of the Unit Base Transformation to the Interpolation of Secondary Energy Distributions

International Nuclear Information System (INIS)

T Sutton; T Trumbull

2005-01-01

Secondary neutron energy spectra used by Monte Carlo codes are often provided in tabular format. Examples are the spectra obtained from ENDF/B-VI File 5 when the LF parameter has the value 1. These secondary spectra are tabulated on an incident energy mesh, and in a Monte Carlo calculation the tabulated spectra are generally interpolated to the energy of the incident neutron. A common method of interpolation involves the use of the unit base transformation. The details of the implementation vary from code to code, so here we will simply focus on the mathematics of the method. Given an incident neutron with energy E, the bracketing points E i and E i+1 on the incident energy mesh are determined. The corresponding secondary energy spectra are transformed to a dimensionless energy coordinate system in which the secondary energies lie between zero and one. A dimensionless secondary energy is then sampled from a spectrum obtained by linearly interpolating the transformed spectra--often using the method of statistical interpolation. Finally, the sampled secondary energy is transformed back into the normal energy coordinate system. For this inverse transformation, the minimum and maximum energies are linearly interpolated from the values given in the non-transformed secondary spectra. The purpose of the unit base transformation is to preserve (as nearly as possible) the physics of the secondary distribution--in particular the minimum and maximum energies possible for the secondary neutron. This method is used by several codes including MCNP and the new MC21 code that is the subject of this paper. In comparing MC21 results to those of MCNP, it was discovered that the nuclear data supplied to MCNP is structured in such a way that the code may not be doing the best possible job of preserving the physics of certain nuclear interactions. In this paper, we describe the problem and explain how it may be avoided

Asymptotically and exactly energy balanced augmented flux-ADER schemes with application to hyperbolic conservation laws with geometric source terms

Science.gov (United States)

Navas-Montilla, A.; Murillo, J.

2016-07-01

In this work, an arbitrary order HLL-type numerical scheme is constructed using the flux-ADER methodology. The proposed scheme is based on an augmented Derivative Riemann solver that was used for the first time in Navas-Montilla and Murillo (2015) [1]. Such solver, hereafter referred to as Flux-Source (FS) solver, was conceived as a high order extension of the augmented Roe solver and led to the generation of a novel numerical scheme called AR-ADER scheme. Here, we provide a general definition of the FS solver independently of the Riemann solver used in it. Moreover, a simplified version of the solver, referred to as Linearized-Flux-Source (LFS) solver, is presented. This novel version of the FS solver allows to compute the solution without requiring reconstruction of derivatives of the fluxes, nevertheless some drawbacks are evidenced. In contrast to other previously defined Derivative Riemann solvers, the proposed FS and LFS solvers take into account the presence of the source term in the resolution of the Derivative Riemann Problem (DRP), which is of particular interest when dealing with geometric source terms. When applied to the shallow water equations, the proposed HLLS-ADER and AR-ADER schemes can be constructed to fulfill the exactly well-balanced property, showing that an arbitrary quadrature of the integral of the source inside the cell does not ensure energy balanced solutions. As a result of this work, energy balanced flux-ADER schemes that provide the exact solution for steady cases and that converge to the exact solution with arbitrary order for transient cases are constructed.

How to Transform, with a Capacitor, Thermal Energy into Usable Work

Science.gov (United States)

Miranda, E. N.

2010-01-01

The temperature dependence of the dielectric permittivity is taken into account to study the energy change in a capacitor that follows a cycle between a cold and a hot thermal reservoir. There is a net energy gain in the process that, in principle, can be transformed into usable work. The paper is simple enough as to be used with keen…

High-energy infrared femtosecond pulses generated by dual-chirped optical parametric amplification.

Science.gov (United States)

Fu, Yuxi; Takahashi, Eiji J; Midorikawa, Katsumi

2015-11-01

We demonstrate high-energy infrared femtosecond pulse generation by a dual-chirped optical parametric amplification (DC-OPA) scheme [Opt. Express19, 7190 (2011)]. By employing a 100 mJ pump laser, a signal pulse energy exceeding 20 mJ at a wavelength of 1.4 μm was achieved before dispersion compensation. A total output energy of 33 mJ was recorded. Under a further energy scaling condition, the signal pulse was compressed to an almost transform-limited duration of 27 fs using a fused silica prism compressor. Since the DC-OPA scheme is efficient and energy scalable, design parameters for obtaining 100 mJ level infrared pulses are presented, which are suitable as driver lasers for the energy scaling of high-order harmonic generation with sub-keV photon energy.

Designing and developing an accreditation scheme for renewable energy with full consultation of interested parties

Energy Technology Data Exchange (ETDEWEB)

Denne, T.; Wakerley, S.

1998-11-01

This document sets out a plan for the development of a labelling system to promote consumer sales of New and Renewable Electricity. A New and Renewable Electricity Verification Scheme is a mechanism to assist the development of an end-user market in new and renewable electricity. It provides two key features: a means for separately tracking new and renewable electricity using a methodology for verifying generation source; and a label for identifying new and renewable electricity (NRE) as a distinct product. The objectives of the scheme would be to: provide customers wishing to purchase NRE with confidence in the product; and to provide value to the new and renewable energy sector. (author)

A modified symplectic PRK scheme for seismic wave modeling

Science.gov (United States)

Liu, Shaolin; Yang, Dinghui; Ma, Jian

2017-02-01

A new scheme for the temporal discretization of the seismic wave equation is constructed based on symplectic geometric theory and a modified strategy. The ordinary differential equation in terms of time, which is obtained after spatial discretization via the spectral-element method, is transformed into a Hamiltonian system. A symplectic partitioned Runge-Kutta (PRK) scheme is used to solve the Hamiltonian system. A term related to the multiplication of the spatial discretization operator with the seismic wave velocity vector is added into the symplectic PRK scheme to create a modified symplectic PRK scheme. The symplectic coefficients of the new scheme are determined via Taylor series expansion. The positive coefficients of the scheme indicate that its long-term computational capability is more powerful than that of conventional symplectic schemes. An exhaustive theoretical analysis reveals that the new scheme is highly stable and has low numerical dispersion. The results of three numerical experiments demonstrate the high efficiency of this method for seismic wave modeling.

Privacy protection schemes for fingerprint recognition systems

Science.gov (United States)

Marasco, Emanuela; Cukic, Bojan

2015-05-01

The deployment of fingerprint recognition systems has always raised concerns related to personal privacy. A fingerprint is permanently associated with an individual and, generally, it cannot be reset if compromised in one application. Given that fingerprints are not a secret, potential misuses besides personal recognition represent privacy threats and may lead to public distrust. Privacy mechanisms control access to personal information and limit the likelihood of intrusions. In this paper, image- and feature-level schemes for privacy protection in fingerprint recognition systems are reviewed. Storing only key features of a biometric signature can reduce the likelihood of biometric data being used for unintended purposes. In biometric cryptosystems and biometric-based key release, the biometric component verifies the identity of the user, while the cryptographic key protects the communication channel. Transformation-based approaches only a transformed version of the original biometric signature is stored. Different applications can use different transforms. Matching is performed in the transformed domain which enable the preservation of low error rates. Since such templates do not reveal information about individuals, they are referred to as cancelable templates. A compromised template can be re-issued using a different transform. At image-level, de-identification schemes can remove identifiers disclosed for objectives unrelated to the original purpose, while permitting other authorized uses of personal information. Fingerprint images can be de-identified by, for example, mixing fingerprints or removing gender signature. In both cases, degradation of matching performance is minimized.

An energy signature scheme for steam trap assessment and flow rate estimation using pipe-induced acoustic measurements

Science.gov (United States)

Olama, Mohammed M.; Allgood, Glenn O.; Kuruganti, Teja P.; Lake, Joe E.

2012-06-01

The US Congress has passed legislation dictating that all government agencies establish a plan and process for improving energy efficiencies at their sites. In response to this legislation, Oak Ridge National Laboratory (ORNL) has recently conducted a pilot study to explore the deployment of a wireless sensor system for a real-time measurement-based energy efficiency optimization framework within the steam distribution system within the ORNL campus. We make assessments on the real-time status of the distribution system by observing the state measurements of acoustic sensors mounted on the steam pipes/traps/valves. In this paper, we describe a spectral-based energy signature scheme that interprets acoustic vibration sensor data to estimate steam flow rates and assess steam traps health status. Experimental results show that the energy signature scheme has the potential to identify different steam trap health status and it has sufficient sensitivity to estimate steam flow rate. Moreover, results indicate a nearly quadratic relationship over the test region between the overall energy signature factor and flow rate in the pipe. The analysis based on estimated steam flow and steam trap status helps generate alerts that enable operators and maintenance personnel to take remedial action. The goal is to achieve significant energy-saving in steam lines by monitoring and acting on leaking steam pipes/traps/valves.

A new representation for ground states and its Legendre transforms

International Nuclear Information System (INIS)

Cedillo, A.

1994-01-01

The ground-state energy of an electronic system is a functional of the number of electrons (N) and the external potential (v): E = E(N,V), this is the energy representation for ground states. In 1982, Nalewajski defined the Legendre transforms of this representation, taking advantage of the strict concavity of E with respect to their variables (concave respect v and convex respect N), and he also constructed a scheme for the reduction of derivatives of his representations. Unfortunately, N and the electronic density (p) were the independent variables of one of these representations, but p depends explicitly on N. In this work, this problem is avoided using the energy per particle (ε) as the basic variables, and the Legendre transformations can be defined. A procedure for the reduction of derivatives is generated for the new four representations and, in contrast to the Nalewajski's procedure, it only includes derivatives of the four representations. Finally, the reduction of derivatives is used to test some relationships between the hardness and softness kernels

Improved QRD-M Detection Algorithm for Generalized Spatial Modulation Scheme

Directory of Open Access Journals (Sweden)

Xiaorong Jing

2017-01-01

Full Text Available Generalized spatial modulation (GSM is a spectral and energy efficient multiple-input multiple-output (MIMO transmission scheme. It will lead to imperfect detection performance with relatively high computational complexity by directly applying the original QR-decomposition with M algorithm (QRD-M to the GSM scheme. In this paper an improved QRD-M algorithm is proposed for GSM signal detection, which achieves near-optimal performance but with relatively low complexity. Based on the QRD, the improved algorithm firstly transforms the maximum likelihood (ML detection of the GSM signals into searching an inverted tree structure. Then, in the searching process of the M branches, the branches corresponding to the illegitimate transmit antenna combinations (TACs and related to invalid number of active antennas are cut in order to improve the validity of the resultant branches at each level by taking advantage of characteristics of GSM signals. Simulation results show that the improved QRD-M detection algorithm provides similar performance to maximum likelihood (ML with the reduced computational complexity compared to the original QRD-M algorithm, and the optimal value of parameter M of the improved QRD-M algorithm for detection of the GSM scheme is equal to modulation order plus one.

Evaluating direct energy savings and market transformation effects: A decade of technical design assistance in the northwestern USA

International Nuclear Information System (INIS)

Van Den Wymelenberg, Kevin; Brown, G.Z.; Burpee, Heather; Djunaedy, Ery; Gladics, Gunnar; Kline, Jeff; Loveland, Joel; Meek, Christopher; Thimmanna, Harshana

2013-01-01

This paper documents the direct energy savings and energy efficiency market transformation impacts of a multi-state design assistance program in the northwestern US. The paper addresses four specific aims. (1) It provides a conservative and justified estimate of the direct energy savings associated with design assistance activities of a market transformation program from 2001 to 2010. (2) It provides a rigorous methodology to evaluate direct energy savings associated with design assistance market transformation programs. (3) It provides a low-cost replicable method to predict energy savings in new buildings by evaluating the integrated design process. (4) It provides quantitative indicators useful for estimating indirect energy savings from market transformation. Applying the recommended analysis method and assuming a 12-year measure life, the direct energy savings of the population (626 buildings; 51,262,000 ft 2 ) is estimated as 45.3 aMW (average megawatts) (electric), and 265,738.089 therms (non-electric). If the entire program budget were divided into the electric savings only, the Lab Network cost per kWh saved ranged from $0.0016 to $0.003 using the recommended method and $0.0092/kWh using the most conservative method. These figures do not isolate contextual influences or represent total resource cost. Statistically significant correlations (r 2 =0.1−0.3) between integrated design scores and energy savings are reported. - Highlights: ► Estimated direct energy savings of a market transformation program are presented. ► A methodology to evaluate energy savings from multiple baselines is documented. ► Level of integrated design can be used to estimate energy savings in new buildings. ► Quantitative evaluation indicators of efficiency market transformation are provided. ► Electric energy saved from design assistance costs between $0.0016 and $0.0092/kWh.

A Simple Sensorless Scheme for Induction Motor Drives Fed by a Matrix Converter Using Constant Air-Gap Flux and PQR Transformation

DEFF Research Database (Denmark)

Blaabjerg, Frede; Lee, Kyo Beum

2007-01-01

This paper presents a new and simple method for sensorless operation of matrix converter drives using a constant air-gap flux and the imaginary power flowing to the motor. To improve low-speed sensorless performance, the non-linearities of a matrix converter drive such as commutation delays, turn......-on and turn-off times of switching devices, and on-state switching device voltage drop are modeled using PQR transformation and compensated using a reference current control scheme. The proposed compensation method is applied for high performance induction motor drives using a 3 kW matrix converter system...

Cognitive radio networks dynamic resource allocation schemes

CERN Document Server

Wang, Shaowei

2014-01-01

This SpringerBrief presents a survey of dynamic resource allocation schemes in Cognitive Radio (CR) Systems, focusing on the spectral-efficiency and energy-efficiency in wireless networks. It also introduces a variety of dynamic resource allocation schemes for CR networks and provides a concise introduction of the landscape of CR technology. The author covers in detail the dynamic resource allocation problem for the motivations and challenges in CR systems. The Spectral- and Energy-Efficient resource allocation schemes are comprehensively investigated, including new insights into the trade-off

Review and comparison study of hybrid diesel/solar/hydro/fuel cell energy schemes for a rural ICT Telecenter

Energy Technology Data Exchange (ETDEWEB)

Abdullah, M.O.; Yung, V.C.; Anyi, M.; Othman, A.K.; Ab. Hamid, K.B. [Universiti Malaysia Sarawak (UNIMAS), 94300 Kota Samarahan, Sarawak (Malaysia); Tarawe, J. [e-Bario ICT Telecenter, Bario, Sarawak (Malaysia)

2010-02-15

In this paper, the rural electrification study of an ICT Telecenter in particular reference to the Kelabit Highland of Sarawak is presented. The use of diesel generator and its associated environmental implications is first discussed. The cost-effectiveness of the present solar PV system and the solar/hydro schemes for rural electrification of the rural ICT are evaluated employing the HOMER simulation software, considering sustainability factors such as system efficiency, weather, fuel costs, operating and maintaining costs. Subsequently, simple novel Hybrid Energy Performance Equations and the associated Energy Performance Curves are derived and introduced, respectively, which provide a visualization model, simplifying hybrid system analysis. Results obtained in this study have shown that combined power schemes is more sustainable in terms of supplying electricity to the Telecenter compared to a stand-alone PV system due to prolong cloudy and dense haze periods. The hybrid systems can have efficiency range of {proportional_to}15%-75% compared to PV stand-alone of only {proportional_to}10%, indicating hybrid systems are more reliable and sustainable - in minimizing both energy losses and excess energy. (author)

Signal detection without finite-energy limits to quantum resolution

OpenAIRE

Luis Aina, Alfredo

2013-01-01

We show that there are extremely simple signal detection schemes where the finiteness of energy resources places no limit on the resolution. On the contrary, larger resolution can be obtained with lower energy. To this end the generator of the signal-dependent transformation encoding the signal information on the probe state must be different from the energy. We show that the larger the deviation of the probe state from being the minimum-uncertainty state, the better the resolution.

Low-energy phenomenological chiral Lagrangians

International Nuclear Information System (INIS)

Cavopol, A.V.

1987-01-01

We develop a phenomenological Lagrangian that satisfies the requirements of the so called alternative schemes designed to model low energy meson phenomenology. Linear and nonlinear σ type Lagrangians and symmetry breaking schemes are used to describe pions that exhibit masses proportional to the square of the symmetry breaking term's coefficient, ε. (m π 2 ∼ 0(ε 2 )). The invariance of the theory under coordinate dependent transformations is achieved by introducing gauge fields for both linear and nonlinear Lagrangians. Finally, analogies between the minimal symmetry breaking terms in Quantum Electrodynamics and in our phenomenological lagrangians are used to generate a discussion of the quark-pion mass dependence indicated by the model

A novel grain cluster-based homogenization scheme

International Nuclear Information System (INIS)

Tjahjanto, D D; Eisenlohr, P; Roters, F

2010-01-01

An efficient homogenization scheme, termed the relaxed grain cluster (RGC), for elasto-plastic deformations of polycrystals is presented. The scheme is based on a generalization of the grain cluster concept. A volume element consisting of eight (= 2 × 2 × 2) hexahedral grains is considered. The kinematics of the RGC scheme is formulated within a finite deformation framework, where the relaxation of the local deformation gradient of each individual grain is connected to the overall deformation gradient by the, so-called, interface relaxation vectors. The set of relaxation vectors is determined by the minimization of the constitutive energy (or work) density of the overall cluster. An additional energy density associated with the mismatch at the grain boundaries due to relaxations is incorporated as a penalty term into the energy minimization formulation. Effectively, this penalty term represents the kinematical condition of deformation compatibility at the grain boundaries. Simulations have been performed for a dual-phase grain cluster loaded in uniaxial tension. The results of the simulations are presented and discussed in terms of the effective stress–strain response and the overall deformation anisotropy as functions of the penalty energy parameters. In addition, the prediction of the RGC scheme is compared with predictions using other averaging schemes, as well as to the result of direct finite element (FE) simulation. The comparison indicates that the present RGC scheme is able to approximate FE simulation results of relatively fine discretization at about three orders of magnitude lower computational cost

Enhanced machine learning scheme for energy efficient resource allocation in 5G heterogeneous cloud radio access networks

KAUST Repository

Alqerm, Ismail

2018-02-15

Heterogeneous cloud radio access networks (H-CRAN) is a new trend of 5G that aims to leverage the heterogeneous and cloud radio access networks advantages. Low power remote radio heads (RRHs) are exploited to provide high data rates for users with high quality of service requirements (QoS), while high power macro base stations (BSs) are deployed for coverage maintenance and low QoS users support. However, the inter-tier interference between the macro BS and RRHs and energy efficiency are critical challenges that accompany resource allocation in H-CRAN. Therefore, we propose a centralized resource allocation scheme using online learning, which guarantees interference mitigation and maximizes energy efficiency while maintaining QoS requirements for all users. To foster the performance of such scheme with a model-free learning, we consider users\\' priority in resource blocks (RBs) allocation and compact state representation based learning methodology to enhance the learning process. Simulation results confirm that the proposed resource allocation solution can mitigate interference, increase energy and spectral efficiencies significantly, and maintain users\\' QoS requirements.

Renewable energy production support schemes for residential-scale solar photovoltaic systems in Nordic conditions

International Nuclear Information System (INIS)

Hirvonen, Janne; Kayo, Genku; Cao, Sunliang; Hasan, Ala; Sirén, Kai

2015-01-01

The objective of this study was to examine the effect of production-based support schemes on the economic feasibility of residential-scale PV systems (1–10 kW) in Finland. This was done by calculating the payback time for various sizes of newly installed PV systems for a Finnish detached house with district heating. Three types of economic support schemes (guaranteed selling price, fixed premiums and self-consumption incentives) were tested in an hourly simulation. The load of the building was based on real-life measurements, while PV output was simulated with TRNSYS software. The energy results were post-processed with economic data in MATLAB to find the payback time. Hourly electricity prices from the Nordic energy market were used with PV system prices from Finnish companies. Unsubsidised residential PV systems in Finland had payback times of more than 40 years. The production-based support for PV generation needs to be two to three times the buying price of electricity, to make it possible to pay back the initial investment in 20 years. Low capacity systems with more than 50% self-consumption (under 3 kW) were favoured by self-consumption incentives, while high capacity systems with less than 40% self-consumption (over 5 kW) were favoured by the FIT-type support schemes. - Highlights: • Unsubsidised residential PV is uneconomical in Finland. • Support rate must be 2 times the electricity price for reasonable payback time. • Even using all electricity on-site is not profitable enough without support. • Assumed real interest rate had great influence on payback time. • Hourly electricity prices are much lower than average values from Finnish statistics

Psychosocial routes from housing investment to health: Evidence from England's home energy efficiency scheme

International Nuclear Information System (INIS)

Gilbertson, Jan; Grimsley, Michael; Green, Geoff

2012-01-01

Over the past decade the Warm Front Scheme has been the English Government's principal programme for improving domestic energy efficiency and reducing fuel poverty. This paper reports on a cross-sectional survey of low income householders participating in the Warm Front Scheme in five urban areas of England. Surveys were conducted of 2685 individuals, before and or after intervention. Pathways to self reported health were modelled by logistic regression. Of all the dimensions of health examined, only self reported mental health is directly associated with Warm Front measures. Intermediary variables associated with Warm Front intervention were shown to be significantly correlated with more dimensions of self reported health status. Higher temperatures, satisfaction with the heating system, greater thermal comfort, reductions in fuel poverty and lower stress were significantly correlated with improved health. Alleviating fuel poverty and reducing stress appeared to be the main route to health. We conclude there are complex and indirect relationships linking energy efficiency measures to outcomes on all dimensions of health which contribute to significant material and psychosocial benefits. The impact of the Warm Front Scheme cannot be fully understood by a limited analysis which merely relates indoor temperature and property characteristics to physiological health outcomes. - Highlights: ► Warm Front improvements are linked to significant material and psychosocial benefits. ► The alleviation of fuel poverty and the reduction of stress emerge as the likely route to health. ► The scope for improving health is greater than implied by the UK Government's Fuel Poverty Strategy. ► A dual but integrated approach to alleviating cold living conditions and fuel poverty is required.

A Study on an Energy Conservation and Interconnection Scheme between WSN and Internet Based on the 6LoWPAN

Directory of Open Access Journals (Sweden)

Runtong Zhang

2015-01-01

Full Text Available Wireless sensor network (WSN, which has broad application prospects, consists of small nodes with sensing, computation, and communications capabilities. IPv6 is used over low power WPAN (wireless personal area network which is run by 6LoWPAN technology on the LoWPAN devices. In order to establish seamless connection of two heterogeneous networks, that is, WSN and IPv6 network, this paper proposes an improved energy conservation and interconnection scheme (ECIS based on the analysis of the current schemes. Detailed design of each functional component in the new scheme is proposed, and an expansion of the SSCS module in NS2 802.15.4 simulator is examined. Comprehensive experiments on the simulation platform show that the newly proposed scheme is advantageous over existing results.

Transmutor demo unit and thermal into electrical energy transformation problems

International Nuclear Information System (INIS)

Matal, O.; Fiedler, J.

1999-01-01

In the three circuits layout of the transmutor the heat is transferred from the primary through the secondary circuits by a favourable heat carrier into the tertiary circuit where the thermal into electrical energy transformation in turbo-generator comes into force. Properties as well as parameters of the heat carrier in the secondary circuit affect basically both the conceptual layout of the tertiary circuit and consequently investments costs for its realization and the effectiveness of the transformation of thermal into electrical energy. For several heat carriers considered for the transmutor secondary circuit particular tertiary circuit concepts for the demonstration transmutor unit of approx. 15 W thermal power rate are analyzed, layout features and possibilities of turbogenerator selection are commented and investment costs as well as effectiveness of thermal into electrical energy transformation are estimated. Some of the results are as follows: (i) Heat carrier properties influence thermodynamics of the TDU water/steam cycle substantially. One of the dominant parameters is the melting (freezing) temperature of the heat carrier. (ii) Heat carrier properties influence investment costs of components of the TDU tertiary circuit substantially. Dominantly influenced are costs of the steam generator, steam turbine and high pressure regeneration system. (iii) If the heat carrier has to be a molten salt than a salt with a low melting temperature is recommended to be selected, for example KHF2. (iv) Eutectic alloy Pb-Bi as the heat carrier serves changes to design the TDU with efficient thermodynamics, with acceptable low investment costs of the tertiary as well as secondary circuit components and with an acceptable level of the nuclear safety

LOW COMPLEXITY HYBRID LOSSY TO LOSSLESS IMAGE CODER WITH COMBINED ORTHOGONAL POLYNOMIALS TRANSFORM AND INTEGER WAVELET TRANSFORM

Directory of Open Access Journals (Sweden)

R. Krishnamoorthy

2012-05-01

Full Text Available In this paper, a new lossy to lossless image coding scheme combined with Orthogonal Polynomials Transform and Integer Wavelet Transform is proposed. The Lifting Scheme based Integer Wavelet Transform (LS-IWT is first applied on the image in order to reduce the blocking artifact and memory demand. The Embedded Zero tree Wavelet (EZW subband coding algorithm is used in this proposed work for progressive image coding which achieves efficient bit rate reduction. The computational complexity of lower subband coding of EZW algorithm is reduced in this proposed work with a new integer based Orthogonal Polynomials transform coding. The normalization and mapping are done on the subband of the image for exploiting the subjective redundancy and the zero tree structure is obtained for EZW coding and so the computation complexity is greatly reduced in this proposed work. The experimental results of the proposed technique also show that the efficient bit rate reduction is achieved for both lossy and lossless compression when compared with existing techniques.

A parameterization scheme for the x-ray linear attenuation coefficient and energy absorption coefficient.

Science.gov (United States)

Midgley, S M

2004-01-21

A novel parameterization of x-ray interaction cross-sections is developed, and employed to describe the x-ray linear attenuation coefficient and mass energy absorption coefficient for both elements and mixtures. The new parameterization scheme addresses the Z-dependence of elemental cross-sections (per electron) using a simple function of atomic number, Z. This obviates the need for a complicated mathematical formalism. Energy dependent coefficients describe the Z-direction curvature of the cross-sections. The composition dependent quantities are the electron density and statistical moments describing the elemental distribution. We show that it is possible to describe elemental cross-sections for the entire periodic table and at energies above the K-edge (from 6 keV to 125 MeV), with an accuracy of better than 2% using a parameterization containing not more than five coefficients. For the biologically important elements 1 coefficients. At higher energies, the parameterization uses fewer coefficients with only two coefficients needed at megavoltage energies.

Using the building energy simulation test (BESTEST) to evaluate CHENATH, the Nationwide House Energy Rating Scheme Simulation Engine

Energy Technology Data Exchange (ETDEWEB)

Delsante, A.E. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Highett, VIC (Australia). Div. of Building Construction and Engineering

1995-12-31

The Nationwide House Energy Rating Scheme (NatHERS) uses a simulation program as its reference tool to evaluate the energy demand of buildings. The Commonwealth Scientific Industrial Research Organisation (CSIRO) developed software called CHENATH, is a significantly enhanced version of the CHEETAH simulation program. As part of the NatHERS development process, it was considered important to subject CHENATH to further testing. Two separate evaluation projects were undertaken. This paper describes one of these projects. CHENATH was compared with a reference set of eight internationally recognized simulation programs using the BESTEST methodology. Annual heating and cooling energy requirements were compared for a specified set of variations on a simple double-glazed building. Annual incident and transmitted solar radiation was also compared, for which CHENATH agreed very well with the reference set. It also agreed well for heating energy, but tended to over-predict cooling energy. This is largely because it controls an environmental temperature rather than the required air temperature. For the same reason CHENATH over-predicted heating and cooling demands. No major discrepancies were found that would suggest bugs in the program. (author). 4 tabs., 10 figs., 4 refs.

High thermal efficiency x-ray energy conversion scheme for advanced fusion reactors

International Nuclear Information System (INIS)

Quimby, D.C.; Taussig, R.T.; Hertzberg, A.

1977-01-01

This paper reports on a new radiation energy conversion scheme which appears to be capable of producing electricity from the high quality x-ray energy with efficiencies of 60 to 70 percent. This new reactor concept incorporates a novel x-ray radiation boiler and a new thermal conversion device known as an energy exchanger. The low-Z first walls of the radiation boiler are semi-transparent to x-rays, and are kept cool by incoming working fluid, which is subsequently heated to temperatures of 2000 to 3000 0 K in the interior of the boiler by volumetric x-ray absorption. The radiation boiler may be a compact part of the reactor shell since x-rays are readily absorbed in high-Z materials. The energy exchanger transfers the high-temperature working fluid energy to a lower temperature gas which drives a conventional turbine. The overall efficiency of the cycle is characterized by the high temperature of the working fluid. The high thermal efficiencies which appear achievable with this cycle would make an otherwise marginal advanced fusion reactor into an attractive net power producer. The operating principles, initial conceptual design, and engineering problems of the radiation boiler and thermal cycle are presented

An Antenna Diversity Scheme for Digital Front-End with OFDM Technology

Institute of Scientific and Technical Information of China (English)

Fa-Long Luol; Ward Williams; Bruce Gladstone

2011-01-01

In,this paper, we propose a new antenna diversity scheme for OFDM-based wireless communication and digital broadcasting applications. Compared with existing schemes, such as post-fast Fourier transform （FFT）, pre-FFT, and polyphase-based fitter-bank, the proposed scheme performs optimally and has very low computational complexity. It offers a better compromise between performance, power consumption, and complexity in real-time implementation of the receivers of broadband communication and digital broadcasting systems.

A real options approach to analyse wind energy investments under different support schemes

International Nuclear Information System (INIS)

Kitzing, Lena; Juul, Nina; Drud, Michael; Boomsma, Trine Krogh

2017-01-01

Highlights: • Real options model for wind projects considering investment timing and sizing. • Introducing a capacity constraint in the optimisation. • Addressing several uncertainty factors while still providing analytical solution. • Comparative policy analysis of investment incentives from different support schemes. • Improved quantification of trade-off between fast deployment and large projects. - Abstract: A real options model is developed to evaluate wind energy investments in a realistic and easily applicable way. Considering optimal investment timing and sizing (capacity choice), the model introduces a capacity constraint as part of the optimisation. Several correlated uncertainty factors are combined into a single stochastic process, which allows for analytical (closed-form) solutions. The approach is well suited for quantitative policy analysis, such as the comparison of different support schemes. A case study for offshore wind in the Baltic Sea quantifies differences in investment incentives under feed-in tariffs, feed-in premiums and tradable green certificates. Investors can under certificate schemes require up to 3% higher profit margins than under tariffs due to higher variance in profits. Feed-in tariffs may lead to 15% smaller project sizes. This trade-off between faster deployment of smaller projects and slower deployment of larger projects is neglected using traditional net present value approaches. In the analysis of such trade-off, previous real options studies did not consider a capacity constraint, which is here shown to decrease the significance of the effect. The impact on investment incentives also depends on correlations between the underlying stochastic factors. The results may help investors to make informed investment decisions and policy makers to strategically design renewable support and develop tailor-made incentive schemes.

Simple Examples of the Interpretation of Changes in Kinetic and Potential Energy Under Galilean Transformations

Science.gov (United States)

Ginsberg, Edw. S.

2018-02-01

The compatibility of the Newtonian formulation of mechanical energy and the transformation equations of Galilean relativity is demonstrated for three simple examples of motion treated in most introductory physics courses (free fall, a frictionless inclined plane, and a mass/spring system). Only elementary concepts and mathematics, accessible to students at that level, are used. Emphasis is on pedagogy and concepts related to the transformation properties of potential energy.

Electrostatic energy harvesting device with out-of-the-plane gap closing scheme

DEFF Research Database (Denmark)

Wang, Fei; Hansen, Ole

2014-01-01

In this paper, we report on an electrostatic energy harvester with an out-of-the-plane gap closing scheme. Using advanced MEMS technology, energy harvesting devices formed by a four wafer stack are batch fabricated and fully packaged at wafer scale. A spin coated CYTOP polymer is used both...... as an electret material and an adhesive layer for low temperature wafer bonding. The overall size of the device is about 1.1 cm × 1.3 cm. At an external load resistance of 13.4 MΩ, a power output of 0.15 μW is achieved when vibration at an acceleration amplitude of 1 g (∼9.8 m/s2) is applied at a low frequency...... of 96 Hz. The frequency response of the device is also measured and a broader bandwidth is observed at higher acceleration amplitude....

Electrostatic energy harvesting device with out-of-the-plane gap closing scheme

DEFF Research Database (Denmark)

Wang, Fei; Hansen, Ole

2013-01-01

In this paper, we report on an electrostatic energy harvester with an out-of-the-plane gap closing scheme. Using advanced MEMS technology, energy harvesting devices with a four wafer stack are batch fabricated and fully packaged at wafer scale. CYTOP polymer is used both as an electret material...... and an adhesive layer for low temperature wafer bonding. The overall size of the device is about 1.1×1.3 cm2. With an external load of 13.4 MΩ, a power output of 0.15 μW is achieved when vibration at an acceleration amplitude of 1 g (9.8 m/s2) is applied at a low frequency of 96 Hz. The frequency response...... of the device is also measured and a broader bandwidth is observed at higher acceleration amplitude. © 2013 IEEE....

A lightweight security scheme for wireless body area networks: design, energy evaluation and proposed microprocessor design.

Science.gov (United States)

Selimis, Georgios; Huang, Li; Massé, Fabien; Tsekoura, Ioanna; Ashouei, Maryam; Catthoor, Francky; Huisken, Jos; Stuyt, Jan; Dolmans, Guido; Penders, Julien; De Groot, Harmke

2011-10-01

In order for wireless body area networks to meet widespread adoption, a number of security implications must be explored to promote and maintain fundamental medical ethical principles and social expectations. As a result, integration of security functionality to sensor nodes is required. Integrating security functionality to a wireless sensor node increases the size of the stored software program in program memory, the required time that the sensor's microprocessor needs to process the data and the wireless network traffic which is exchanged among sensors. This security overhead has dominant impact on the energy dissipation which is strongly related to the lifetime of the sensor, a critical aspect in wireless sensor network (WSN) technology. Strict definition of the security functionality, complete hardware model (microprocessor and radio), WBAN topology and the structure of the medium access control (MAC) frame are required for an accurate estimation of the energy that security introduces into the WBAN. In this work, we define a lightweight security scheme for WBAN, we estimate the additional energy consumption that the security scheme introduces to WBAN based on commercial available off-the-shelf hardware components (microprocessor and radio), the network topology and the MAC frame. Furthermore, we propose a new microcontroller design in order to reduce the energy consumption of the system. Experimental results and comparisons with other works are given.

Optimized difference schemes for multidimensional hyperbolic partial differential equations

Directory of Open Access Journals (Sweden)

Adrian Sescu

2009-04-01

Full Text Available In numerical solutions to hyperbolic partial differential equations in multidimensions, in addition to dispersion and dissipation errors, there is a grid-related error (referred to as isotropy error or numerical anisotropy that affects the directional dependence of the wave propagation. Difference schemes are mostly analyzed and optimized in one dimension, wherein the anisotropy correction may not be effective enough. In this work, optimized multidimensional difference schemes with arbitrary order of accuracy are designed to have improved isotropy compared to conventional schemes. The derivation is performed based on Taylor series expansion and Fourier analysis. The schemes are restricted to equally-spaced Cartesian grids, so the generalized curvilinear transformation method and Cartesian grid methods are good candidates.

Optimal on/off scheme for all-optical switching

DEFF Research Database (Denmark)

Kristensen, Philip Trøst; Heuck, Mikkel; Mørk, Jesper

2012-01-01

We present a two-pulsed on/off scheme based on coherent control for fast switching of the optical energy in a micro cavity and use calculus of variations to optimize the switching in terms of energy.......We present a two-pulsed on/off scheme based on coherent control for fast switching of the optical energy in a micro cavity and use calculus of variations to optimize the switching in terms of energy....

Dynamic Diffraction Studies on the Crystallization, Phase Transformation, and Activation Energies in Anodized Titania Nanotubes

Directory of Open Access Journals (Sweden)

Hani Albetran

2018-02-01

Full Text Available The influence of calcination time on the phase transformation and crystallization kinetics of anodized titania nanotube arrays was studied using in-situ isothermal and non-isothermal synchrotron radiation diffraction from room temperature to 900 °C. Anatase first crystallized at 400 °C, while rutile crystallized at 550 °C. Isothermal heating of the anodized titania nanotubes by an increase in the calcination time at 400, 450, 500, 550, 600, and 650 °C resulted in a slight reduction in anatase abundance, but an increase in the abundance of rutile because of an anatase-to-rutile transformation. The Avrami equation was used to model the titania crystallization mechanism and the Arrhenius equation was used to estimate the activation energies of the titania phase transformation. Activation energies of 22 (10 kJ/mol for the titanium-to-anatase transformation, and 207 (17 kJ/mol for the anatase-to-rutile transformation were estimated.

Dynamic Diffraction Studies on the Crystallization, Phase Transformation, and Activation Energies in Anodized Titania Nanotubes.

Science.gov (United States)

Albetran, Hani; Vega, Victor; Prida, Victor M; Low, It-Meng

2018-02-23

The influence of calcination time on the phase transformation and crystallization kinetics of anodized titania nanotube arrays was studied using in-situ isothermal and non-isothermal synchrotron radiation diffraction from room temperature to 900 °C. Anatase first crystallized at 400 °C, while rutile crystallized at 550 °C. Isothermal heating of the anodized titania nanotubes by an increase in the calcination time at 400, 450, 500, 550, 600, and 650 °C resulted in a slight reduction in anatase abundance, but an increase in the abundance of rutile because of an anatase-to-rutile transformation. The Avrami equation was used to model the titania crystallization mechanism and the Arrhenius equation was used to estimate the activation energies of the titania phase transformation. Activation energies of 22 (10) kJ/mol for the titanium-to-anatase transformation, and 207 (17) kJ/mol for the anatase-to-rutile transformation were estimated.

Developing benefit schemes and financial compensation measures for fishermen impacted by marine renewable energy projects

International Nuclear Information System (INIS)

Reilly, Kieran; O’Hagan, Anne Marie; Dalton, Gordon

2016-01-01

Commercial fishermen are arguably the stakeholder group most likely to be directly impacted by the expansion of the marine renewable energy (MRE) sector. The potential opposition of fishermen may hinder the development of MRE projects and the provision of benefit schemes could to enhance acceptance. Benefit schemes refer to additional voluntary measures that are provided by a developer to local stakeholders. The aim of this study is to explore the issue of the provision of benefit packages to local fishing communities and financial compensation measures for fishermen who may be impacted by MRE projects. Semi-structured interviews were conducted with fourteen fishermen from three separate case study sites around the island of Ireland where MRE projects were being developed. In addition, ten company fisheries liaison officers (CFLOs) who have worked on MRE projects in the UK and Ireland were also interviewed. The interviews were analysed under the headings of local employment, benefits in kind, compensation and community funds and ownership of projects. Analysis shows that there is uncertainty among fishermen over whether they would benefit or gain employment from MRE. Provision of re-training schemes and preferential hiring practices could be used by MRE developers to reduce this uncertainty. There was also agreement between fishermen and CFLOs on the need for the provision of an evidence-base and a standard approach for the calculation of disruption payments. A formal structure for the provision of benefit schemes for fishermen would be useful. Furthermore, schemes that provide a range of benefits to fishermen and other stakeholders over the lifetime of a MRE project are more likely to be successful at enhancing acceptance. - Highlights: • There is uncertainty among fishermen over benefits from MRE projects. • Re-training is required for fishermen to avail of employment opportunities. • Evidence-base is required for calculation of disruption payments. �

First Investigations on the Energy Deposited in a D0 early separation scheme Dipole for the LHC upgrade

CERN Document Server

Hoa, C

2007-01-01

This note gives the first results of energy deposition calculation on a simplified model for an early scheme separation dipole D0, located at 3.5 m from the IP. The Monte Carlo code FLUKA version 2006.3 has been used for modelling the multi-particle interactions and energy transport. After a short introduction to particle interaction with matter and power deposition processes, the FLUKA modelling is described with bench marked power deposition calculation on the TAS, the absorber located in front of the triplet quadrupoles. The power deposition results for the D0 early scheme are then discussed in details, with the averaged and peak power density, and the variations of the total heat load in the dipole with the longitudinal position and with the aperture diameter.

Discrete quantum Fourier transform in coupled semiconductor double quantum dot molecules

International Nuclear Information System (INIS)

Dong Ping; Yang Ming; Cao Zhuoliang

2008-01-01

In this Letter, we present a physical scheme for implementing the discrete quantum Fourier transform in a coupled semiconductor double quantum dot system. The main controlled-R gate operation can be decomposed into many simple and feasible unitary transformations. The current scheme would be a useful step towards the realization of complex quantum algorithms in the quantum dot system

Magnetic bead detection using nano-transformers

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyung Kwon; Ahn, Doyeol [Institute of Quantum Information Processing and Systems, University of Seoul, 90 Jeonnong, Dongdaemun, Seoul 130-743 (Korea, Republic of); Hwang, Jong Seung; Hwang, Sung Woo, E-mail: dahn@uos.ac.kr [Research Center for Time-domain Nano-functional Devices and School of Electrical Engineering, Korea University, 5-1 Anam, Sungbuk, Seoul 136-701 (Korea, Republic of)

2010-11-19

A novel scheme to detect magnetic beads using a nano-scale transformer with a femtoweber resolution is reported. We have performed a Faraday's induction experiment with the nano-transformer at room temperature. The transformer shows the linear output voltage responses to the sinusoidal input current. When magnetic beads are placed on the transformer, the output responses are increased by an amount corresponding to the added magnetic flux from the beads when compared with the case of no beads on the transformer. In this way, we could determine whether magnetic beads are on top of the transformer in a single particle level.

Magnetic bead detection using nano-transformers.

Science.gov (United States)

Kim, Hyung Kwon; Hwang, Jong Seung; Hwang, Sung Woo; Ahn, Doyeol

2010-11-19

A novel scheme to detect magnetic beads using a nano-scale transformer with a femtoweber resolution is reported. We have performed a Faraday's induction experiment with the nano-transformer at room temperature. The transformer shows the linear output voltage responses to the sinusoidal input current. When magnetic beads are placed on the transformer, the output responses are increased by an amount corresponding to the added magnetic flux from the beads when compared with the case of no beads on the transformer. In this way, we could determine whether magnetic beads are on top of the transformer in a single particle level.

Comparation of the support schemes for generation of electricity from renewable energy sources and their influence on the electricity pr ices for the final electricity customers in Republic of Macedonia

International Nuclear Information System (INIS)

Veljanovska, Natasha

2013-01-01

Renewable energy is the first source of energy used by the man since his existence, using the wood as a source for heating and warming, as well as for cooking. Today, the use of renewable energy is one of the main goals of the energy policies in the world. The use of renewable energy contributes in increasing security of supply, decreasing import dependence of fossil fuels and improving socioeconomic stability. The use of renewable energy directly contributes in reducing the intensity of climate change, providing local development and job creation. The thesis addresses the concept of the support schemes for electricity generation from renewable energy, more specifically, the manner of their application for fulfillment of the national targets for the share of energy from renewable sources in the total energy consumption. The thesis is developed covering three important aspects of support schemes: the possibility for implementation of appropriate support scheme in the Republic of Macedonia; the influence of support scheme on the electricity price for the customers; and the determination of the feed-in tariffs. The main contributions of the thesis are: determination of influence of the feed-in tariffs as appropriate support scheme for electricity generation from renewable energy in the Republic of Macedonia on the electricity price for the customers, as well as the determination of the feed-in tariffs. The thesis presents an overview of the support schemes for electricity generation from renewable energy, with emphasis on new measures developed for the needs of fulfillment of the national targets for the share of energy from renewable sources in the total energy consumption. The thesis also presents the detail characteristics support schemes and possibility for their implementation in the Republic of Macedonia. This research is a confirmation of the initial selection of feed-in tariffs as an appropriate support scheme for renewable energy in the Republic of Macedonia

A Transforming Electricity System: Understanding the Interactions Between Clean Energy Technologies, Markets, and Policies

Science.gov (United States)

Mooney, David

The U.S. electricity system is currently undergoing a dramatic transformation. State-level renewable portfolio standards, abundant natural gas at low prices, and rapidly falling prices for wind and solar technologies are among the factors that have ushered in this transformation. With objective, rigorous, technology-neutral analysis, NREL aims to increase the understanding of energy policies, markets, resources, technologies, and infrastructure and their connections with economic, environmental, and security priorities. The results of these analyses are meant to inform R&D, policy, and investment decisions as energy-efficient and renewable energy technologies advance from concept to commercial application to market penetration. This talk will provide an overview of how NREL uses high-fidelity data, deep knowledge of energy technology cost and performance, and advanced models and tools to provide the information needed to ensure this transformation occurs economically, while maintaining system reliability. Examples will be explored and will include analysis of tax credit impacts on wind and solar deployment and power sector emissions, as well as analysis of power systems operations in the Eastern Interconnection under 30% wind and solar penetration scenarios. Invited speaker number 47185.

Noiseless Vlasov–Poisson simulations with linearly transformed particles

Energy Technology Data Exchange (ETDEWEB)

Campos Pinto, Martin, E-mail: campos@ann.jussieu.fr [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); CNRS, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005, Paris (France); UPMC Univ. Paris 06, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005, Paris (France); Sonnendrücker, Eric, E-mail: sonnen@math.unistra.fr [IRMA, UMR 7501, Université de Strasbourg and CNRS, 7 rue René Descartes, F-67084 Strasbourg Cedex (France); Project-team CALVI, INRIA Nancy Grand Est, 7 rue René Descartes, F-67084 Strasbourg Cedex (France); Friedman, Alex, E-mail: af@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Grote, David P., E-mail: grote1@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Lund, Steve M., E-mail: smlund@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

2014-10-15

We introduce a deterministic discrete-particle simulation approach, the Linearly-Transformed Particle-In-Cell (LTPIC) method, that employs linear deformations of the particles to reduce the noise traditionally associated with particle schemes. Formally, transforming the particles is justified by local first order expansions of the characteristic flow in phase space. In practice the method amounts of using deformation matrices within the particle shape functions; these matrices are updated via local evaluations of the forward numerical flow. Because it is necessary to periodically remap the particles on a regular grid to avoid excessively deforming their shapes, the method can be seen as a development of Denavit's Forward Semi-Lagrangian (FSL) scheme (Denavit, 1972 [8]). However, it has recently been established (Campos Pinto, 2012 [20]) that the underlying Linearly-Transformed Particle scheme converges for abstract transport problems, with no need to remap the particles; deforming the particles can thus be seen as a way to significantly lower the remapping frequency needed in the FSL schemes, and hence the associated numerical diffusion. To couple the method with electrostatic field solvers, two specific charge deposition schemes are examined, and their performance compared with that of the standard deposition method. Finally, numerical 1d1v simulations involving benchmark test cases and halo formation in an initially mismatched thermal sheet beam demonstrate some advantages of our LTPIC scheme over the classical PIC and FSL methods. Benchmarked test cases also indicate that, for numerical choices involving similar computational effort, the LTPIC method is capable of accuracy comparable to or exceeding that of state-of-the-art, high-resolution Vlasov schemes.

Analysis of Energy Overshoot of High Frequency Waves with Wavelet Transform

Institute of Scientific and Technical Information of China (English)

WEN Fan

2000-01-01

A study is made on the overshoot phenomena in wind-generated waves. The surface displace ments of time-growing waves are measured at four fetches in a wind wave channel. The evolution of high frequency waves is displayed with wavelet transform. The results are compared with Sutherland＇s. It is found that high frequency wave components experience much stronger energy overshoot in the evolution.The energy of high frequency waves decreases greatly after overshoot

Performance comparison of renewable incentive schemes using optimal control

International Nuclear Information System (INIS)

Oak, Neeraj; Lawson, Daniel; Champneys, Alan

2014-01-01

Many governments worldwide have instituted incentive schemes for renewable electricity producers in order to meet carbon emissions targets. These schemes aim to boost investment and hence growth in renewable energy industries. This paper examines four such schemes: premium feed-in tariffs, fixed feed-in tariffs, feed-in tariffs with contract for difference and the renewable obligations scheme. A generalised mathematical model of industry growth is presented and fitted with data from the UK onshore wind industry. The model responds to subsidy from each of the four incentive schemes. A utility or ‘fitness’ function that maximises installed capacity at some fixed time in the future while minimising total cost of subsidy is postulated. Using this function, the optimal strategy for provision and timing of subsidy for each scheme is calculated. Finally, a comparison of the performance of each scheme, given that they use their optimal control strategy, is presented. This model indicates that the premium feed-in tariff and renewable obligation scheme produce the joint best results. - Highlights: • Stochastic differential equation model of renewable energy industry growth and prices, using UK onshore wind data 1992–2010. • Cost of production reduces as cumulative installed capacity of wind energy increases, consistent with the theory of learning. • Studies the effect of subsidy using feed-in tariff schemes, and the ‘renewable obligations’ scheme. • We determine the optimal timing and quantity of subsidy required to maximise industry growth and minimise costs. • The premium feed-in tariff scheme and the renewable obligations scheme produce the best results under optimal control

Appraisal of bio-hydrogen production schemes

International Nuclear Information System (INIS)

Bent Sorensen

2006-01-01

Work is ongoing on several schemes of biological hydrogen production. At one end is the genetic modification of biological systems (such as algae or cyanobacteria) to produce hydrogen from photosynthesis, instead of the energy-rich compounds (such as NADPH 2 ) normally constituting the endpoint of the transformations through the photo-systems. A second route is to collect and use the biomass produced by normal plant growth processes in a separate step that produces hydrogen. This may be done similar to biogas production by fermentation, where the endpoint is methane (plus CO 2 and minor constituents). Hydrogen could be the outcome of a secondary process starting from methane, involving any of the conventional methods of hydrogen production from natural gas. An alternative to fermentation is gasification of the biomass, followed by a shift-reaction leading to hydrogen. I compare advantages and disadvantages of these three routes, notably factors such as system efficiency, cost and environmental impacts, and also compare them to liquid biofuels. (author)

A Novel Energy Efficient Topology Control Scheme Based on a Coverage-Preserving and Sleep Scheduling Model for Sensor Networks

OpenAIRE

Shi, Binbin; Wei, Wei; Wang, Yihuai; Shu, Wanneng

2016-01-01

In high-density sensor networks, scheduling some sensor nodes to be in the sleep mode while other sensor nodes remain active for monitoring or forwarding packets is an effective control scheme to conserve energy. In this paper, a Coverage-Preserving Control Scheduling Scheme (CPCSS) based on a cloud model and redundancy degree in sensor networks is proposed. Firstly, the normal cloud model is adopted for calculating the similarity degree between the sensor nodes in terms of their historical d...

A Framework of Secured Embedding Scheme Using Vector Discrete Wavelet Transformation and Lagrange Interpolation

Directory of Open Access Journals (Sweden)

Maheswari Subramanian

2018-01-01

Full Text Available Information hiding techniques have a significant role in recent application areas. Steganography is the embedding of information within an innocent cover work in a way which cannot be detected by any person without accessing the steganographic key. The proposed work uses a steganographic scheme for useful information with the help of human skin tone regions as cover image. The proposed algorithm has undergone Lagrange interpolation encryption for enhancement of the security of the hidden information. First, the skin tone regions are identified by using YCbCr color space which can be used as a cover image. Image pixels which belong to the skin regions are used to carry more secret bits, and the secret information is hidden in both horizontal and vertical sequences of the skin areas of the cover image. The secret information will hide behind the human skin regions rather than other objects in the same image because the skin pixels have high intensity value. The performance of embedding is done and is quite invisible by the vector discrete wavelet transformation (VDWT technique. A new Lagrange interpolation-based encryption method is introduced to achieve high security of the hidden information with higher payload and better visual quality.

Schemes for Probabilistic Teleportation of an Unknown Three-Particle Three-Level Entangled State

Institute of Scientific and Technical Information of China (English)

无

2006-01-01

In this paper, two schemes for teleporting an unknown three-particle three-level entangled state are proposed. In the first scheme, two partial three-particle three-level entangled states are used as the quantum channels, while in the second scheme, three two-particle three-level non-maximally entangled states are employed as quantum channels.It is shown that the teleportation can be successfully realized with certain probability, for both two schemes, if a receiver adopts some appropriate unitary transformations. It is shown also that the successful probabilities of these two schemes are different.

Modelling of Sudan’s Energy Supply, Transformation, and Demand

Directory of Open Access Journals (Sweden)

Ali A. Rabah

2016-01-01

Full Text Available The study aimed to develop energy flow diagram (Sankey diagram of Sudan for the base year 2014. The developed Sankey diagram is the first of its kind in Sudan. The available energy balance for the base year 2012 is a simple line draw and did not count the energy supply by private and mixed sectors such as sugar and oil industries and marine and civil aviation. The private and mixed sectors account for about 7% of the national grid electric power. Four energy modules are developed: resources, transformation, demand, and export and import modules. The data are obtained from relevant Sudanese ministries and directorates and Sudan Central Bank. “e!Sankey 4 pro” software is used to develop the Sankey diagram. The main primary types of energy in Sudan are oil, hydro, biomass, and renewable energy. Sudan has a surplus of gasoline, petroleum coke, and biomass and deficit in electric power, gasoil, jet oil, and LPG. The surplus of gasoline is exported; however, the petroleum coke is kept as reserve. The deficit is covered by import. The overall useful energy is 76% and the loss is 24%. The useful energy is distributed among residential (38%, transportation (33%, industry (12%, services (16%, and agriculture (1% sectors.

The renormalization group: scale transformations and changes of scheme

International Nuclear Information System (INIS)

Roditi, I.

1983-01-01

Starting from a study of perturbation theory, the renormalization group is expressed, not only for changes of scale but also within the original view of Stueckelberg and Peterman, for changes of renormalization scheme. The consequences that follow from using that group are investigated. Following a more general point of view a method to obtain an improvement of the perturbative results for physical quantities is proposed. The results obtained with this method are compared with those of other existing methods. (L.C.) [pt

Efficient direct solar-to-hydrogen conversion by in situ interface transformation of a tandem structure

Science.gov (United States)

May, Matthias M.; Lewerenz, Hans-Joachim; Lackner, David; Dimroth, Frank; Hannappel, Thomas

2015-09-01

Photosynthesis is nature's route to convert intermittent solar irradiation into storable energy, while its use for an industrial energy supply is impaired by low efficiency. Artificial photosynthesis provides a promising alternative for efficient robust carbon-neutral renewable energy generation. The approach of direct hydrogen generation by photoelectrochemical water splitting utilizes customized tandem absorber structures to mimic the Z-scheme of natural photosynthesis. Here a combined chemical surface transformation of a tandem structure and catalyst deposition at ambient temperature yields photocurrents approaching the theoretical limit of the absorber and results in a solar-to-hydrogen efficiency of 14%. The potentiostatically assisted photoelectrode efficiency is 17%. Present benchmarks for integrated systems are clearly exceeded. Details of the in situ interface transformation, the electronic improvement and chemical passivation are presented. The surface functionalization procedure is widely applicable and can be precisely controlled, allowing further developments of high-efficiency robust hydrogen generators.

Feasibility of industrial wind energy schemes - final report

International Nuclear Information System (INIS)

Gow, G.

1998-01-01

This document is the final report of an investigation into the feasibility of using wind turbines as on-site generation (i.e. on the customer''s side of the meter) to meet a proportion of the electricity demand on industrial sites in the UK. It was thought that this could become a promising market for wind energy outside support mechanisms such as the Non Fossil Fuel Obligation and equivalents, for the following principal reasons: electricity which displaces purchases from a Public Electricity Supplier (PES) or Second Tier Support (STS) has a higher value than electricity sold direct to a PES or STS; there could be seasonal and diurnal correlation between the output of wind turbines and electricity prices; and due to existing infrastructure, realisation of such projects could be simpler and cheaper than for new wind farms. Six industrial sites participated in the project, covering a wide range of industries, locations, and wind regimes. For each site, a year of concurrent wind data and demand data was produced. Practical aspects of the implementation of such schemes, and the results of the time step analyses, were discussed with the participating sites and the host PESs for each site. (author)

Feasibility of industrial wind energy schemes - final report

Energy Technology Data Exchange (ETDEWEB)

Gow, G.

1998-04-01

This document is the final report of an investigation into the feasibility of using wind turbines as on-site generation (i.e. on the customer's side of the meter) to meet a proportion of the electricity demand on industrial sites in the UK. It was thought that this could become a promising market for wind energy outside support mechanisms such as the Non Fossil Fuel Obligation and equivalents, for the following principal reasons: electricity which displaces purchases from a Public Electricity Supplier (PES) or Second Tier Support (STS) has a higher value than electricity sold direct to a PES or STS; there could be seasonal and diurnal correlation between the output of wind turbines and electricity prices; and due to existing infrastructure, realisation of such projects could be simpler and cheaper than for new wind farms. Six industrial sites participated in the project, covering a wide range of industries, locations, and wind regimes. For each site, a year of concurrent wind data and demand data was produced. Practical aspects of the implementation of such schemes, and the results of the time step analyses, were discussed with the participating sites and the host PESs for each site. (author)

Integral transformations applied to image encryption

International Nuclear Information System (INIS)

Vilardy, Juan M.; Torres, Cesar O.; Perez, Ronal

2017-01-01

In this paper we consider the application of the integral transformations for image encryption through optical systems, a mathematical algorithm under Matlab platform using fractional Fourier transform (FrFT) and Random Phase Mask (RPM) for digital images encryption is implemented. The FrFT can be related to others integral transforms, such as: Fourier transform, Sine and Cosine transforms, Radial Hilbert transform, fractional Sine transform, fractional Cosine transform, fractional Hartley transform, fractional Wavelet transform and Gyrator transform, among other transforms. The encryption scheme is based on the use of the FrFT, the joint transform correlator and two RPMs, which provide security and robustness to the implemented security system. One of the RPMs used during encryption-decryption and the fractional order of the FrFT are the keys to improve security and make the system more resistant against security attacks. (paper)

Wind power and market integration, comparative study of financing schemes

International Nuclear Information System (INIS)

2013-10-01

The financing scheme of renewable energies is a key factor for their development pace and cost. As some countries like France, Germany or Spain have chosen a Feed-in Tariff (FiT) scheme, there are in fact four possible financing schemes: FiT, ex-post prime, ex-ante prime, and quotas (green certificates). A market convergence is then supposed to meet two main objectives: the control of market distortions related to wind energy development, and the optimization of wind energy production with respect to market signals. The authors analyse the underlying economic challenges and the ability of financing schemes to meet these objectives within a short term horizon (2015). They present the different financing schemes, analyse the impact of three key economic factors (market distortion, production optimization, financing costs)

Imaging ultrasonic dispersive guided wave energy in long bones using linear radon transform.

Science.gov (United States)

Tran, Tho N H T; Nguyen, Kim-Cuong T; Sacchi, Mauricio D; Le, Lawrence H

2014-11-01

Multichannel analysis of dispersive ultrasonic energy requires a reliable mapping of the data from the time-distance (t-x) domain to the frequency-wavenumber (f-k) or frequency-phase velocity (f-c) domain. The mapping is usually performed with the classic 2-D Fourier transform (FT) with a subsequent substitution and interpolation via c = 2πf/k. The extracted dispersion trajectories of the guided modes lack the resolution in the transformed plane to discriminate wave modes. The resolving power associated with the FT is closely linked to the aperture of the recorded data. Here, we present a linear Radon transform (RT) to image the dispersive energies of the recorded ultrasound wave fields. The RT is posed as an inverse problem, which allows implementation of the regularization strategy to enhance the focusing power. We choose a Cauchy regularization for the high-resolution RT. Three forms of Radon transform: adjoint, damped least-squares, and high-resolution are described, and are compared with respect to robustness using simulated and cervine bone data. The RT also depends on the data aperture, but not as severely as does the FT. With the RT, the resolution of the dispersion panel could be improved up to around 300% over that of the FT. Among the Radon solutions, the high-resolution RT delineated the guided wave energy with much better imaging resolution (at least 110%) than the other two forms. The Radon operator can also accommodate unevenly spaced records. The results of the study suggest that the high-resolution RT is a valuable imaging tool to extract dispersive guided wave energies under limited aperture. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Study of the scheme of two-beam accelerator driver with accompanying electromagnetic wave

International Nuclear Information System (INIS)

Elzhov, A.V.; Kaminskij, A.K.; Kazacha, V.I.; Perel'shtejn, E.A.; Sedykh, S.N.; Sergeev, A.P.

2000-01-01

A novel scheme of two-beam accelerator (TBA) driver based on a linear induction accelerator is considered. In this scheme the bunched beam propagates in the accompanying enhanced microwave that provides the steady longitudinal beam bunching along the whole driver. A travelling wave tube (TWT) is used as the wave-slowing periodic structure. Major merits of the driver scheme in hand are the possibilities of providing the microwave phase and amplitude stability and the preliminary beam bunching at a rather low initial energy (∼ 1 MeV). The numerical simulation has shown that a steady state could be found when electron bunches accompanied by an amplified microwave are simultaneously accelerated in the external electric field. The total power, which is inserted into the beam by the accelerating field, transforms into the microwave power in the steady state. The first set of experiments was fulfilled with the buncher on the base of the JINR LIU-3000 linac (electron beam energy ∼ 600 keV, electron current ∼ 150 A). The considerable level of the amplified microwave power (∼ 5 MW) and high enough bunching parameter (∼ 0.4) were obtained. The electron beam bunching at the frequency of 36.4 GHz was registered by means of the Cherenkov radiation of the electron bunches that occurred at their passing through the special target. The beam keeps a high bunching level at the distance ∼ 10 cm from the TWT exit being accompanied by the amplified microwave

Darboux Transformations for Energy-Dependent Potentials and the Klein–Gordon Equation

International Nuclear Information System (INIS)

Schulze-Halberg, Axel

2013-01-01

We construct explicit Darboux transformations for a generalized Schrödinger-type equation with energy-dependent potential, a special case of which is the stationary Klein–Gordon equation. Our results complement and generalize former findings (Lin et al., Phys Lett A 362:212–214, 2007).

An active defrost scheme with a balanced energy consumption and food quality loss in supermarket refrigeration systems

DEFF Research Database (Denmark)

Cai, Junping; Stoustrup, Jakob; Rasmussen, Bjarne Dindler

2008-01-01

This paper introduces food quality as a new parameter, together with energy, to determine an optimal cooling time between defrost cycles. A new defrost-on-demand scheme is proposed. It uses a feedback loop consisting of on-line model updating and estimation as well as a model based optimization. ...

The Fractional Fourier Transform and Its Application to Energy Localization Problems

Directory of Open Access Journals (Sweden)

ter Morsche Hennie G

2003-01-01

Full Text Available Applying the fractional Fourier transform (FRFT and the Wigner distribution on a signal in a cascade fashion is equivalent to a rotation of the time and frequency parameters of the Wigner distribution. We presented in ter Morsche and Oonincx, 2002, an integral representation formula that yields affine transformations on the spatial and frequency parameters of the -dimensional Wigner distribution if it is applied on a signal with the Wigner distribution as for the FRFT. In this paper, we show how this representation formula can be used to solve certain energy localization problems in phase space. Examples of such problems are given by means of some classical results. Although the results on localization problems are classical, the application of generalized Fourier transform enlarges the class of problems that can be solved with traditional techniques.

Real-time Fourier transformation of lightwave spectra and application in optical reflectometry.

Science.gov (United States)

Malacarne, Antonio; Park, Yongwoo; Li, Ming; LaRochelle, Sophie; Azaña, José

2015-12-14

We propose and experimentally demonstrate a fiber-optics scheme for real-time analog Fourier transform (FT) of a lightwave energy spectrum, such that the output signal maps the FT of the spectrum of interest along the time axis. This scheme avoids the need for analog-to-digital conversion and subsequent digital signal post-processing of the photo-detected spectrum, thus being capable of providing the desired FT processing directly in the optical domain at megahertz update rates. The proposed concept is particularly attractive for applications requiring FT analysis of optical spectra, such as in many optical Fourier-domain reflectrometry (OFDR), interferometry, spectroscopy and sensing systems. Examples are reported to illustrate the use of the method for real-time OFDR, where the target axial-line profile is directly observed in a single-shot oscilloscope trace, similarly to a time-of-flight measurement, but with a resolution and depth of range dictated by the underlying interferometry scheme.

Non Standard Finite Difference Scheme for Mutualistic Interaction Description

OpenAIRE

Gabbriellini, Gianluca

2012-01-01

One of the more interesting themes of the mathematical ecology is the description of the mutualistic interaction between two interacting species. Based on continuous-time model developed by Holland and DeAngelis 2009 for consumer-resource mutualism description, this work deals with the application of the Mickens Non Standard Finite Difference method to transform the continuous-time scheme into a discrete-time one. It has been proved that the Mickens scheme is dynamically consistent with the o...

The impact of Chinese carbon emission trading scheme (ETS) on low carbon energy (LCE) investment

International Nuclear Information System (INIS)

Mo, Jian-Lei; Agnolucci, Paolo; Jiang, Mao-Rong; Fan, Ying

2016-01-01

China is planning to introduce emission trading scheme (ETS) to decrease CO_2 emission. As low carbon energy (LCE) will play a pivotal role in reducing CO_2 emissions, our paper is to assess the extent and the conditions under which a carbon ETS can deliver LCE investment in China. We chose wind technology as a case study and a real-option based model was built to explore the impact of a number of variables and design features on investment decisions, e.g. carbon and electricity price, carbon market risk, carbon price floor and ceiling and on-grid ratio. We compute critical values of these variables and features and explore trade-offs among them. According to our work, a carbon ETS has a significant effect on wind power plant investment although it cannot support investment in wind power on its own. Carbon price stabilization mechanisms such as carbon price floor can significantly improve the effect of carbon ETS but the critical floor to support investment is still much higher than the carbon price in China pilot ETSs. Our results show that other policy measures will be needed to promote low-carbon energy development in China. - Highlights: • The impact of Chinese emission trading scheme on low carbon energy investment is assessed. • A real-option based investment decision model under uncertainty is built and employed. • Key variables and features of ETS influencing wind power investment are explored. • Chinese carbon ETS cannot support low carbon energy investment on its own. • Other policy measures complementing ETS are still needed and should be coordinated.

LevelScheme: A level scheme drawing and scientific figure preparation system for Mathematica

Science.gov (United States)

Caprio, M. A.

2005-09-01

LevelScheme is a scientific figure preparation system for Mathematica. The main emphasis is upon the construction of level schemes, or level energy diagrams, as used in nuclear, atomic, molecular, and hadronic physics. LevelScheme also provides a general infrastructure for the preparation of publication-quality figures, including support for multipanel and inset plotting, customizable tick mark generation, and various drawing and labeling tasks. Coupled with Mathematica's plotting functions and powerful programming language, LevelScheme provides a flexible system for the creation of figures combining diagrams, mathematical plots, and data plots. Program summaryTitle of program:LevelScheme Catalogue identifier:ADVZ Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVZ Operating systems:Any which supports Mathematica; tested under Microsoft Windows XP, Macintosh OS X, and Linux Programming language used:Mathematica 4 Number of bytes in distributed program, including test and documentation:3 051 807 Distribution format:tar.gz Nature of problem:Creation of level scheme diagrams. Creation of publication-quality multipart figures incorporating diagrams and plots. Method of solution:A set of Mathematica packages has been developed, providing a library of level scheme drawing objects, tools for figure construction and labeling, and control code for producing the graphics.

Local unitary transformation method for large-scale two-component relativistic calculations: case for a one-electron Dirac Hamiltonian.

Science.gov (United States)

Seino, Junji; Nakai, Hiromi

2012-06-28

An accurate and efficient scheme for two-component relativistic calculations at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level is presented. The present scheme, termed local unitary transformation (LUT), is based on the locality of the relativistic effect. Numerical assessments of the LUT scheme were performed in diatomic molecules such as HX and X(2) (X = F, Cl, Br, I, and At) and hydrogen halide clusters, (HX)(n) (X = F, Cl, Br, and I). Total energies obtained by the LUT method agree well with conventional IODKH results. The computational costs of the LUT method are drastically lower than those of conventional methods since in the former there is linear-scaling with respect to the system size and a small prefactor.

Using the fast fourier transform in binding free energy calculations.

Science.gov (United States)

Nguyen, Trung Hai; Zhou, Huan-Xiang; Minh, David D L

2018-04-30

According to implicit ligand theory, the standard binding free energy is an exponential average of the binding potential of mean force (BPMF), an exponential average of the interaction energy between the unbound ligand ensemble and a rigid receptor. Here, we use the fast Fourier transform (FFT) to efficiently evaluate BPMFs by calculating interaction energies when rigid ligand configurations from the unbound ensemble are discretely translated across rigid receptor conformations. Results for standard binding free energies between T4 lysozyme and 141 small organic molecules are in good agreement with previous alchemical calculations based on (1) a flexible complex ( R≈0.9 for 24 systems) and (2) flexible ligand with multiple rigid receptor configurations ( R≈0.8 for 141 systems). While the FFT is routinely used for molecular docking, to our knowledge this is the first time that the algorithm has been used for rigorous binding free energy calculations. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

A method for energy and exergy analyses of product transformation processes in industry

International Nuclear Information System (INIS)

Abou Khalil, B.

2008-12-01

After a literature survey enabling the determination of the advantages and drawbacks of existing methods of assessment of the potential energy gains of an industrial site, this research report presents a newly developed method, named Energy and Exergy Analysis of Transformation Processes (or AEEP for Analyse energetique et exergetique des procedes de transformation), while dealing with actual industrial operations, in order to demonstrate the systematic character of this method. The different steps of the method are presented and detailed, one of them, the process analysis, being critical for the application of the developed method. This particular step is then applied to several industrial unitary operations in order to be a base for future energy audits in the concerned industry sectors, as well as to demonstrate its generic and systematic character. The method is the then applied in a global manner to a cheese manufacturing plant, all the different steps of the AEEP being applied. The author demonstrates that AEEP is a systematic method and can be applied to all energy audit levels, moreover to the lowest levels which have a relatively low cost

Reliability Indicators of Urban Electric Network Schemes for Supply of Second and Third Category Consumers

Directory of Open Access Journals (Sweden)

M. A. Korotkevich

2012-01-01

Full Text Available The paper considers two schemes of the urban distributive electric network for supply of the second and third category consumers for whom indicators of reliability have been determined.As for a network scheme of the 2nd category it has been determined that while installing low-oil and vacuum switches at a distributive point the most remote transformer substation has the highest non-availability  factor which is higher of the corresponding non-availability  factor of the nearest transformer substation by 1,21–1,23 fold  accordingly.As for a network scheme of the 3rd category consumers it has been obtained the data that reliability of consumers receiving supply from bus-bars of transformer substations with 0,38 kW voltage changes  significantly (by 1,2–1,9-fold while changing a breakpoint of the network with 10 kW voltage.

A cancelable biometric scheme based on multi-lead ECGs.

Science.gov (United States)

Peng-Tzu Chen; Shun-Chi Wu; Jui-Hsuan Hsieh

2017-07-01

Biometric technologies offer great advantages over other recognition methods, but there are concerns that they may compromise the privacy of individuals. In this paper, an electrocardiogram (ECG)-based cancelable biometric scheme is proposed to relieve such concerns. In this scheme, distinct biometric templates for a given beat bundle are constructed via "subspace collapsing." To determine the identity of any unknown beat bundle, the multiple signal classification (MUSIC) algorithm, incorporating a "suppression and poll" strategy, is adopted. Unlike the existing cancelable biometric schemes, knowledge of the distortion transform is not required for recognition. Experiments with real ECGs from 285 subjects are presented to illustrate the efficacy of the proposed scheme. The best recognition rate of 97.58 % was achieved under the test condition N train = 10 and N test = 10.

Changing from booster transformer system to auto transformer system in the Kiruna-Raatsi-Svappavaara line in Sweden

Energy Technology Data Exchange (ETDEWEB)

Buelund, A.; Hellstroem, U. [Banverket, Swedisch National Rail Administration Engineering Dept., Borlaenge (Sweden); Varju, G. [Technical Univ. Budapest (Hungary). Dept. of Electrical Power System

1999-07-01

A study of the changeover from a booster transformer (BT) system to an auto transformer (AT) system has been initiated by Banverket to increase the transport capability (weight and speed) of a heavily loaded freight train lines of about 40 km situated between Raatsi and Svappavaara and fed from the Kiruna converter station. In this paper, firstly, a survey of comparison is given on the bases of sophisticated three-conductor line simulations for the two supply schemes in the point of view of equivalent impedance, losses, power rating for actual traffic conditions, longitudinal induction to line-side telecommunication cable, rail-to-earth and rail-to-rail potential. The results of simulation calculations have provided the necessary information on the rating of the AT scheme including the required number and locations of the auto transformers. At AT system has been installed in addition to the already existing BT without the removal of the BT system. This installation has allowed to change from one system to the other in one day period of time and thus giving the possibility of performing real scale comparison tests between the two schemes. The paper presents a survey of the results of two week time site measurements. (orig.)

Definition of Smart Energy City and State of the art of 6 Transform cities using Key Performance Indicators. Deliverable 1.2

Energy Technology Data Exchange (ETDEWEB)

Sieverts Nielsen, P.; Amer, S.B.; Halsnaes, K.

2013-08-15

This report summarises the work undertaken under the EU-FP7 TRANSFORM project for Work Package 1 (part 1): Becoming a Smart Energy City, state of the Art and Ambition. Part 1 starts with a clear outline of each of the participating cities. The work describes the context in terms of climate, energy assets, ambitions, targets and main possibilities in terms of energy efficiency, flows and energy production. After this first step, the work focuses on the description of what a smart energy city is (this report), what the main Key Performance Indicators (KPIs) are that should be met and how this relates to where the current cities and the living labs are. It describes at the same time the current status of city planning, energy planning tools, and existing energy data. The outline should also include information on energy production, energy flows and energy efficiency, where possible. The work will draw largely on existing Strategic Energy Action Plans, Climate Action Plans and planning documents. This report establishes a definition of smart cities, develops Key Elements, Key Performance Indicators and reports on the state of the art regarding the KPIs for the 6 Transform cities. As specified in the Transform proposal, the objective of the evaluation is to identify previous and existing initiatives as a sort of stocktaking on the way to establishing a smart city transformation pathway for each of the participating cities in the Transform project. The definition of a smart energy city and the key performance indicators will be used throughout Transform the guide the work. (Author)

Deficiencies of the cryptography based on multiple-parameter fractional Fourier transform.

Science.gov (United States)

Ran, Qiwen; Zhang, Haiying; Zhang, Jin; Tan, Liying; Ma, Jing

2009-06-01

Methods of image encryption based on fractional Fourier transform have an incipient flaw in security. We show that the schemes have the deficiency that one group of encryption keys has many groups of keys to decrypt the encrypted image correctly for several reasons. In some schemes, many factors result in the deficiencies, such as the encryption scheme based on multiple-parameter fractional Fourier transform [Opt. Lett.33, 581 (2008)]. A modified method is proposed to avoid all the deficiencies. Security and reliability are greatly improved without increasing the complexity of the encryption process. (c) 2009 Optical Society of America.

Optimal control, investment and utilization schemes for energy storage under uncertainty

Science.gov (United States)

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

Regulation control and energy management scheme for wireless power transfer

Science.gov (United States)

Miller, John M.

2015-12-29

Power transfer rate at a charging facility can be maximized by employing a feedback scheme. The state of charge (SOC) and temperature of the regenerative energy storage system (RESS) pack of a vehicle is monitored to determine the load due to the RESS pack. An optimal frequency that cancels the imaginary component of the input impedance for the output signal from a grid converter is calculated from the load of the RESS pack, and a frequency offset f* is made to the nominal frequency f.sub.0 of the grid converter output based on the resonance frequency of a magnetically coupled circuit. The optimal frequency can maximize the efficiency of the power transfer. Further, an optimal grid converter duty ratio d* can be derived from the charge rate of the RESS pack. The grid converter duty ratio d* regulates wireless power transfer (WPT) power level.

Incentive-based Financial Support Scheme for Immature Renewable Energy Systems

DEFF Research Database (Denmark)

Andersen, Morten Thøtt; Frigaard, Peter Bak

2015-01-01

Most of today’s renewable energy systems rely heavily on investments as well as public financial support. This support is often given by means of a higher sales price for each kWh produced, i.e. feed-in tariffs (FITs), green certificates or Renewable Obligation Certificates (ROCs), or by a fixed...... amount, being a percentage of the construction costs of the facility. All these ways of financing have different downsides. The feed-in tariff based kWh prices have some incentives to improve the technology, but enables infeasible solutions to stay financially supported even while R&D is in status quo....... The fixed amount only helps with installation costs, which should not be an issue once the technology is sufficiently feasible. This means that the current ways of granting financial support all lack incentives for increasing production or decreasing construction costs. This paper presents a unique scheme...

A new MV bus transfer scheme for nuclear power plants

International Nuclear Information System (INIS)

Chang, C.K.

2015-01-01

The auxiliary power system of many generating stations consists of offsite power supply system and onsite power supply system, including emergency diesel generators (EDG) to provide secure power to auxiliary loads. If a normal power supply fails to supply power, then the power source is transferred to a standby power supply. In the case of nuclear power plants (NPP), the unit auxiliary transformer (UAT) and standby auxiliary transformer (SAT) - or station service transformer - are installed and powered from 2 offsite power circuits to meet regulatory requirements. The transfer methods of a motor bus from a normal source to a standby source used in power generating stations are fast bus transfer, in-phase transfer, or residual transfer. Fast bus transfer method is the most popular and residual voltage transfer method that is used as a backup in medium voltage buses in general. The use of the advanced technology like open circuit voltage prediction and digital signal processing algorithms can improve the reliability of fast transfer scheme. However, according to the survey results of the recent operation records in nuclear power plants, there were many instances where the fast transfer scheme has failed. To assure bus transfer in any conditions and circumstances, un-interruptible bus transfer scheme utilizing the state of the art medium voltage UPS (Un-interruptible Power Supply) is discussed and elaborated

Performance measures for transform data coding.

Science.gov (United States)

Pearl, J.; Andrews, H. C.; Pratt, W. K.

1972-01-01

This paper develops performance criteria for evaluating transform data coding schemes under computational constraints. Computational constraints that conform with the proposed basis-restricted model give rise to suboptimal coding efficiency characterized by a rate-distortion relation R(D) similar in form to the theoretical rate-distortion function. Numerical examples of this performance measure are presented for Fourier, Walsh, Haar, and Karhunen-Loeve transforms.

Geothermal source heat pumps under energy services companies finance scheme to increase energy efficiency and production in stockbreeding facilities

International Nuclear Information System (INIS)

Borge-Diez, David; Colmenar-Santos, Antonio; Pérez-Molina, Clara; López-Rey, África

2015-01-01

In Europe energy services are underutilized in terms of their potential to improve energy efficiency and reduce external energy dependence. Agricultural and stockbreeding sectors have high potential to improve their energy efficiency. This paper presents an energy model for geothermal source heat pumps in stockbreeding facilities and an analysis of an energy services business case. The proposed solution combines both energy cost reduction and productivity increases and improves energy services company financing scheme. CO 2 emissions drop by 89%, reducing carbon footprint and improving added value for the product. For the two different evaluated scenarios, one including winter heating and one including heating and cooling, high IRR (internal return rate) values are obtained. A sensitivity analysis reveals that the IRR ranges from 10.25% to 22.02%, making the investment attractive. To make the research highly extensible, a sensitivity analysis for different locations and climatic conditions is presented, showing a direct relationship between financial parameters and climatic conditions. A Monte Carlo simulation is performed showing that initial fuel cost and initial investment are the most decisive in the financial results. This work proves that energy services based on geothermal energy can be profitable in these sectors and can increase sustainability, reduce CO 2 emissions and improve carbon footprint. - Highlights: • Geothermal heat pumps are studied to promote industrial energy services. • Geothermal energy in farming facilities improves global competitiveness. • Research shows profitability of low enthalpy geothermal energy services. • Climatic conditions sensitivity analysis reveals IRR ranges from 10.25% to 22.02%. • Added market value for the product as carbon footprint reduction, are achieved

Transport Schemes for Fiber-Wireless Technology: Transmission Performance and Energy Efficiency

Directory of Open Access Journals (Sweden)

Christina Lim

2014-04-01

Full Text Available Fiber-wireless technology has been actively researched as a potential candidate for next generation broadband wireless signal distribution. Despite the popularity, this hybrid scheme has many technical challenges that impede the uptake and commercial deployment. One of the inherent issues is the transport of the wireless signals over a predominantly digital optical network in today’s telecommunication infrastructure. Many different approaches have been introduced and demonstrated with digitized RF transport of the wireless signals being the most compatible with the existing optical fiber networks. In this paper, we review our work in the area of digitized RF transport to address the inherent issues related to analog transport in the fiber-wireless links and compare the transmission performance and energy efficiency with the other transport strategies.

Space–time transformation for the propagator in de Broglie–Bohm ...

Indian Academy of Sciences (India)

2016-09-28

Sep 28, 2016 ... quantum evolution is preserved in its semiclassical scheme through this change. The case ... Keywords. Propagator; de Broglie–Bohm theory; space–time transformation. .... formula of a generalized Fourier transform [24,25].

New horizons for Korean energy industry--shifting paradigms and challenges ahead

International Nuclear Information System (INIS)

Chang, H.-J.Hyun-Joon.

2003-01-01

Korean energy industry is experiencing a radical paradigm shift. Vertically integrated monopoly is being dismantled while state-owned energy companies are privatized. The industry is in transition from extensive government control to more flexible and market-oriented operation. Along with the task of successfully implementing these structural changes, Korea is now faced with challenges of addressing energy security with the decentralized supply system. This paper discusses ongoing efforts to transform electric power and natural gas industries in Korea, and then explores possible schemes for regional energy cooperation that will enhance efficiency and supply security

Upper and lower bounds on the set of recoverable strains and on effective energies in cubic-to-monoclinic martensitic phase transformations

Directory of Open Access Journals (Sweden)

Schlömerkemper Anja

2015-01-01

Full Text Available A major open problem in the mathematical analysis of martensitic phase transformations is the derivation of explicit formulae for the set of recoverable strains and for the relaxed energy of the system. These are governed by the mathematical notion of quasiconvexity. Here we focus on bounds on these quasiconvex hulls and envelopes in the setting of geometrically-linear elasticity. Firstly, we will present mathematical results on triples of transformation strains. This yields further insight into the quasiconvex hull of the twelve transformation strains in cubic-to-monoclinic phase transformations. Secondly, we consider bounds on the energy of such materials based on the so-called energy of mixing thus obtaining a lamination upper bound on the quasiconvex envelope of the energy. Here we present a new algorithm that yields improved upper bounds and allows us to relate numerical results for the lamination upper bound on the energy with theoretical inner bounds on the quasiconvex hull of triples of transformation strains.

Experimental and numerical investigations of the impingement of an oblique liquid jet onto a superhydrophobic surface: energy transformation

Energy Technology Data Exchange (ETDEWEB)

Kibar, Ali, E-mail: alikibar@kocaeli.edu.tr [Department of Mechanical and Material Technologies, Kocaeli University, 41285, Arslanbey Campus, Kocaeli (Turkey)

2016-02-15

This study presents the theory of impinging an oblique liquid jet onto a vertical superhydrophobic surface based on both experimental and numerical results. A Brassica oleracea leaf with a 160° apparent contact angle was used for the superhydrophobic surface. Distilled water was sent onto the vertical superhydrophobic surface in the range of 1750–3050 Reynolds number, with an inclination angle of 20°−40°, using a circular glass tube with a 1.75 mm inner diameter. The impinging liquid jet spread onto the surface governed by the inertia of the liquid and then reflected off the superhydrophobic surface due to the surface energy of the spreading liquid. Two different energy approaches, which have time-scale and per-unit length, were performed to determine transformation of the energy. The kinetic energy of the impinging liquid jet was transformed into the surface energy with an increasing interfacial surface area between the liquid and air during spreading. Afterwards, this surface energy of the spreading liquid was transformed into the reflection kinetic energy. (paper)

The Performance-based Funding Scheme of Universities

Directory of Open Access Journals (Sweden)

Juha KETTUNEN

2016-05-01

Full Text Available The purpose of this study is to analyse the effectiveness of the performance-based funding scheme of the Finnish universities that was adopted at the beginning of 2013. The political decision-makers expect that the funding scheme will create incentives for the universities to improve performance, but these funding schemes have largely failed in many other countries, primarily because public funding is only a small share of the total funding of universities. This study is interesting because Finnish universities have no tuition fees, unlike in many other countries, and the state allocates funding based on the objectives achieved. The empirical evidence of the graduation rates indicates that graduation rates increased when a new scheme was adopted, especially among male students, who have more room for improvement than female students. The new performance-based funding scheme allocates the funding according to the output-based indicators and limits the scope of strategic planning and the autonomy of the university. The performance-based funding scheme is transformed to the strategy map of the balanced scorecard. The new funding scheme steers universities in many respects but leaves the research and teaching skills to the discretion of the universities. The new scheme has also diminished the importance of the performance agreements between the university and the Ministry. The scheme increases the incentives for universities to improve the processes and structures in order to attain as much public funding as possible. It is optimal for the central administration of the university to allocate resources to faculties and other organisational units following the criteria of the performance-based funding scheme. The new funding scheme has made the universities compete with each other, because the total funding to the universities is allocated to each university according to the funding scheme. There is a tendency that the funding schemes are occasionally

Evolutionary algorithm based heuristic scheme for nonlinear heat transfer equations.

Science.gov (United States)

Ullah, Azmat; Malik, Suheel Abdullah; Alimgeer, Khurram Saleem

2018-01-01

In this paper, a hybrid heuristic scheme based on two different basis functions i.e. Log Sigmoid and Bernstein Polynomial with unknown parameters is used for solving the nonlinear heat transfer equations efficiently. The proposed technique transforms the given nonlinear ordinary differential equation into an equivalent global error minimization problem. Trial solution for the given nonlinear differential equation is formulated using a fitness function with unknown parameters. The proposed hybrid scheme of Genetic Algorithm (GA) with Interior Point Algorithm (IPA) is opted to solve the minimization problem and to achieve the optimal values of unknown parameters. The effectiveness of the proposed scheme is validated by solving nonlinear heat transfer equations. The results obtained by the proposed scheme are compared and found in sharp agreement with both the exact solution and solution obtained by Haar Wavelet-Quasilinearization technique which witnesses the effectiveness and viability of the suggested scheme. Moreover, the statistical analysis is also conducted for investigating the stability and reliability of the presented scheme.

Evolutionary algorithm based heuristic scheme for nonlinear heat transfer equations.

Directory of Open Access Journals (Sweden)

Azmat Ullah

Full Text Available In this paper, a hybrid heuristic scheme based on two different basis functions i.e. Log Sigmoid and Bernstein Polynomial with unknown parameters is used for solving the nonlinear heat transfer equations efficiently. The proposed technique transforms the given nonlinear ordinary differential equation into an equivalent global error minimization problem. Trial solution for the given nonlinear differential equation is formulated using a fitness function with unknown parameters. The proposed hybrid scheme of Genetic Algorithm (GA with Interior Point Algorithm (IPA is opted to solve the minimization problem and to achieve the optimal values of unknown parameters. The effectiveness of the proposed scheme is validated by solving nonlinear heat transfer equations. The results obtained by the proposed scheme are compared and found in sharp agreement with both the exact solution and solution obtained by Haar Wavelet-Quasilinearization technique which witnesses the effectiveness and viability of the suggested scheme. Moreover, the statistical analysis is also conducted for investigating the stability and reliability of the presented scheme.

R Peak Detection Method Using Wavelet Transform and Modified Shannon Energy Envelope.

Science.gov (United States)

Park, Jeong-Seon; Lee, Sang-Woong; Park, Unsang

2017-01-01

Rapid automatic detection of the fiducial points-namely, the P wave, QRS complex, and T wave-is necessary for early detection of cardiovascular diseases (CVDs). In this paper, we present an R peak detection method using the wavelet transform (WT) and a modified Shannon energy envelope (SEE) for rapid ECG analysis. The proposed WTSEE algorithm performs a wavelet transform to reduce the size and noise of ECG signals and creates SEE after first-order differentiation and amplitude normalization. Subsequently, the peak energy envelope (PEE) is extracted from the SEE. Then, R peaks are estimated from the PEE, and the estimated peaks are adjusted from the input ECG. Finally, the algorithm generates the final R features by validating R-R intervals and updating the extracted R peaks. The proposed R peak detection method was validated using 48 first-channel ECG records of the MIT-BIH arrhythmia database with a sensitivity of 99.93%, positive predictability of 99.91%, detection error rate of 0.16%, and accuracy of 99.84%. Considering the high detection accuracy and fast processing speed due to the wavelet transform applied before calculating SEE, the proposed method is highly effective for real-time applications in early detection of CVDs.

Transforming shortcomings into opportunities: Can market incentives solve Lebanon's energy crisis?

International Nuclear Information System (INIS)

Ruble, Isabella; Nader, Pamela

2011-01-01

Over the past decades Lebanon's energy sector has been largely ignored and this has led to high economic and environmental costs. The sector is characterized by electricity poverty, an expanding and mainly unregulated transport sector and a lack of energy savings spanning through all sectors of the economy. Recently, the Government of Lebanon has committed to increase the share of renewable energy to 10% of the total energy supply by 2013 and to 12% by the year 2020; it also aims at reducing energy consumption by 6% by the year 2013. This paper aims at contributing to the formulation of a more comprehensive energy strategy for Lebanon by analyzing the recent changes in policy direction and by recommending legal, regulatory and policy measures in order to transform current shortcomings into opportunities allowing the country to become a regional 'success story' in the deployment of renewable energy and energy efficiency. - Research highlights: → This paper reviews the current situation of Lebanon's energy sector. → We analyze the recent development of the markets for renewable energy and energy efficiency. → Policy recommendations that will allow for a sustainable energy future are made.

THE SCHEME WITH THE MULTIPURPOSE RELAY FOR ECONOMY OF ELECTRIC ENERGY IN TO GRAIN THROWER

Directory of Open Access Journals (Sweden)

N. A. Mazukha

2015-01-01

Full Text Available The scheme for economy of electric energy during the work for an example of a grain thrower of the ZME 60 type (Voronezh Region, Semiluki on grain flows in rural economy is offered. Grain thrower can carry out the following technological operations: loading of grain in vehicles; loading and unloading of grain stores; mechanical shoveling of grain on the open areas; separation of grain with office of light impurity. In the scheme the relay 3UG3521/22t (SIEMENS firm is used. The relay can carry out multipurpose protection of engines and comprises the relay of the maximum current, the relay of the minimum current, a timer and the index relay. Temporary charts of the relay 3UG3521/22t are provided in the mode "without preservation" and in the mode with "preservation" for the OVER functions (reaction to growth of current and the UNDER function (reaction to recession of current. Use of the relay 3UG3521/22t allowed to receive protection at long start-up of electric motors, at an overload of electric motors, when idling (for economy of electric energy due to automatic shutdown of the conveyor and at break or jamming of the conveyor. Besides, in the scheme it is offered the multipurpose relay of tension (the relay of control of phases for protection of three engines of a grain thrower at not full-phase modes of a power line. The economy of electric energy can be received in case of, for example, the late actions of the operator for timely shutdown of the engine of a self-feed upon transition of a grain thrower to idling. In practice transition of a grain thrower to the mode of idling is quite often possible in process of reduction of amount of the thrown grain on a platform before a grain thrower. In practice transition of a grain thrower to the mode of idling is quite often possible in process of reduction of amount of the thrown grain on a platform before a grain thrower. The offered electric circuit can be used in the grain thrower and grain loaders

Harvesting energy: Place and local entrepreneurship in community-based renewable energy transition

International Nuclear Information System (INIS)

Süsser, Diana; Döring, Martin; Ratter, Beate M.W.

2017-01-01

Transition towards a renewable energy supply initiates a physical (re)shaping of places and a social transformation of communities into renewable energy communities. Although socio-cultural challenges of energy transition have been recognised (), understandings about socio-geographic places of energy transition and their underlying social processes and structures are insufficiently studied and often remain underestimated. To close this gap, we theoretically and empirically analysed the multifaceted interplay between place, local entrepreneurship and ‘community renewable energy’. Our study is based on an analysis of regional documents and policy reports, and on qualitative interviews undertaken with inhabitants in the case-study municipality of Reußenköge (Germany). Our findings reveal two important aspects: Firstly, people's individual and shared place meanings which materialised in social, physical, historical and climate-related place-attachments and meanings of contested and innovative place are important ingredients bearing an impact on processes of adopting or rejecting renewables. Secondly, differentiated characteristics of entrepreneurs, namely grounded, collaborative, innovative, change-making, economic, communicating, networking and political aspects, appeared to be relevant for the acceptance and support in community-based renewable energy projects. Our findings reveal that energy policies, funding schemes and administrative structures should recognise local socio-geographic important elements in the context of a sustained and decentralised energy transition. - Highlights: • Places are resources of experiences, creativity and innovation for community renewables. • Energy policies should recognise place-based approaches to grassroots community energy actions. • A located view of multifaceted entrepreneurship is relevant to support community renewable energy. • Supportive funding schemes should empower community-based concepts.

Central upwind scheme for a compressible two-phase flow model.

Science.gov (United States)

Ahmed, Munshoor; Saleem, M Rehan; Zia, Saqib; Qamar, Shamsul

2015-01-01

In this article, a compressible two-phase reduced five-equation flow model is numerically investigated. The model is non-conservative and the governing equations consist of two equations describing the conservation of mass, one for overall momentum and one for total energy. The fifth equation is the energy equation for one of the two phases and it includes source term on the right-hand side which represents the energy exchange between two fluids in the form of mechanical and thermodynamical work. For the numerical approximation of the model a high resolution central upwind scheme is implemented. This is a non-oscillatory upwind biased finite volume scheme which does not require a Riemann solver at each time step. Few numerical case studies of two-phase flows are presented. For validation and comparison, the same model is also solved by using kinetic flux-vector splitting (KFVS) and staggered central schemes. It was found that central upwind scheme produces comparable results to the KFVS scheme.

Central upwind scheme for a compressible two-phase flow model.

Directory of Open Access Journals (Sweden)

Munshoor Ahmed

Full Text Available In this article, a compressible two-phase reduced five-equation flow model is numerically investigated. The model is non-conservative and the governing equations consist of two equations describing the conservation of mass, one for overall momentum and one for total energy. The fifth equation is the energy equation for one of the two phases and it includes source term on the right-hand side which represents the energy exchange between two fluids in the form of mechanical and thermodynamical work. For the numerical approximation of the model a high resolution central upwind scheme is implemented. This is a non-oscillatory upwind biased finite volume scheme which does not require a Riemann solver at each time step. Few numerical case studies of two-phase flows are presented. For validation and comparison, the same model is also solved by using kinetic flux-vector splitting (KFVS and staggered central schemes. It was found that central upwind scheme produces comparable results to the KFVS scheme.

Scenarios of energy sobriety and societal transformations. When lifestyle and society changes mean energy savings

International Nuclear Information System (INIS)