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Phan, Qui Tra. "Untersuchungen zur Nutzung der Solarenergie für die Wärme-Kälte-Kopplung unter tropischen Bedingungen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:swb:14-1166198530075-86101.
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Die Untersuchungen zur Nutzung der Solarenergie werden für die klimatischen Bedingungen von Vietnam durchgeführt. Um das Problem der Elektroenergieversorgung in Vietnam zu verringern und um speziell den Lebensstandard in den ländlichen Gebieten zu erhöhen, werden Anstrengungen unternommen, um Anwendungen der Solarenergie zu entwickeln. Es wäre erstrebenswert, wenn ein komplettes Solartechniksystem zur Hausversorgung zur Verfügung stehen würde. Der Konzipierung und Auslegung der Solartechnik wird ein sog. Referenzhaus zugrunde gelegt, das hinsichtlich seiner Bauweise und Größe typisch für die ländlichen Gegenden in Mittel- und Südvietnam ist. Der Gesamtenergiebedarf orientiert sich an der Lebensweise und der Anzahl der Hausbewohner. Erforderlich ist die Bereitstellung von Warmwasser am Tage sowie von Kälte, die für Frischhaltung von Nahrungsmitteln auch nachts erzeugt werden kann. Dies wird als solares Warmwasser- und Kälteerzeugungssystem bezeichnet. Für die Überwindung von Höhenunterschieden bei der Wasserförderung wird ein solarer Stirlingmotor als Pumpenantrieb in Betracht gezogen. Zur Warmwasserbereitung sollen geeignete Solarkollektoren verwendet werden. Zur Kälteerzeugung scheint sich ein Adsorptionskälteaggregat vorteilhaft in das Gesamtsystem einzuordnen.
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Phan, Qui Tra. "Untersuchungen zur Nutzung der Solarenergie für die Wärme-Kälte-Kopplung unter tropischen Bedingungen." Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A23593.
Full textAbstract:
Die Untersuchungen zur Nutzung der Solarenergie werden für die klimatischen Bedingungen von Vietnam durchgeführt. Um das Problem der Elektroenergieversorgung in Vietnam zu verringern und um speziell den Lebensstandard in den ländlichen Gebieten zu erhöhen, werden Anstrengungen unternommen, um Anwendungen der Solarenergie zu entwickeln. Es wäre erstrebenswert, wenn ein komplettes Solartechniksystem zur Hausversorgung zur Verfügung stehen würde. Der Konzipierung und Auslegung der Solartechnik wird ein sog. Referenzhaus zugrunde gelegt, das hinsichtlich seiner Bauweise und Größe typisch für die ländlichen Gegenden in Mittel- und Südvietnam ist. Der Gesamtenergiebedarf orientiert sich an der Lebensweise und der Anzahl der Hausbewohner. Erforderlich ist die Bereitstellung von Warmwasser am Tage sowie von Kälte, die für Frischhaltung von Nahrungsmitteln auch nachts erzeugt werden kann. Dies wird als solares Warmwasser- und Kälteerzeugungssystem bezeichnet. Für die Überwindung von Höhenunterschieden bei der Wasserförderung wird ein solarer Stirlingmotor als Pumpenantrieb in Betracht gezogen. Zur Warmwasserbereitung sollen geeignete Solarkollektoren verwendet werden. Zur Kälteerzeugung scheint sich ein Adsorptionskälteaggregat vorteilhaft in das Gesamtsystem einzuordnen.
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Palm, Kristina. "Det riskabla engagemanget : Om regenerativ utveckling av mänskliga resurser, eldsjälar och ledarskap i radikal utveckling." Doctoral thesis, KTH, Industriell arbetsvetenskap, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4662.
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This thesis concentrates on the consequences of strong commitment⁄ Engagement in contemporary work. The aim of the thesis is to Build knowledge on regeneration and development of human resources. The empirical research consists of three case studies mainly Based on interviews: two are explorative studies on four strongly Committed champions within two projects of radical reorganisation. The third Empirical study is exploring one strongly engaged champion within an extensive Business rationalisation. The two first case studies were originally set for Other research and are therefore analyzed secondarily here. The case studies indicate that the strong commitment that is needed in contemporary Work is problematic when crises arise. The commitment and energy Tend to reduce quickly in bad managed crises. In order to break an evil Circle of energy loss the manager’s support is central, and also the possibility to Learn from experiences in an acceptable climate.Avhandlingen fokuserar på det starka engagemangets konsekvenser i Det samtida arbetet. Syftet är att bidra med förståelse kring engagemangets Betydelse för regenerativ utveckling av mänskliga resurser. Avhandlingen baseras på studier av fem förändringsledare och deras Tre utvecklingsprojekt. Den främsta metoden för insamling av Information var intervjuer, men även andra metoder såsom deltagande observationer Har använts. Av de fem starkt engagerade förändringsledarna som Studerats var det fyra som misslyckades att nå sina projektmål, endast en lyckades Och gick stärkt ur projektet. Två av projekten var radikala, det vill säga de Sökte bryta med befintliga värderingar och organisera arbetet efter en annan Människosyn. Studien visar på att starkt engagemang som ju ofta behövs i ett samtida Gränslöst arbete också kan vara problematiskt när krissituationer uppstår. Individens Engagemang och energi tenderar att förbrukas, istället för att återskapas Vid en illa behandlad kris. För att kunna bryta en ond cirkel av energiförbrukning Föreslås chefers stöd vara en viktig komponent, men också möjligheten Att lära från sina erfarenheter i ett tillåtande klimat.
QC 20100902
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LI, Zhen. "Analysis of dropbox assisted hydraulic traction." Thesis, KTH, Maskinkonstruktion (Inst.), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209486.
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The research looks at the advantages and disadvantages of a hydraulic auxiliary drive (HAD) system which is installed on a 25 meter long timber transport vehicle. The purpose is to investigate the performance with regard to energy, economy and environment of the system due to the added components, the hydraulic accumulators. The auxiliary system that is used on the vehicle is simply a hydrostatic transmission system. Ideally, the fuel consumption and cost can be reduced by using accumulators. To verify this hypothesis, model-based simulations were performed in a software environment and the result was analyzed for a linear and repeatedly accelerating and decelerating driving cycle. Additionally, comparisons were made between the HAD system with and without the assistance of accumulators. From the simulation results, the system assisted by accumulators consumes approximately 14% less fuel than the other. And it produces 15% more tractive effort when the vehicle is accelerating. The paper also includes the determination of the size of accumulators, both theoretically and with simulations. By comparison, there is a small difference between the results from the theoretical calculation and the simulations, which might be caused by a neglecting the volumetric losses in the simulation process. Ideally, an accumulator with a size of 57 L was found to be the most efficient size for the studied driving cycle. Beyond that speed, the efficiency will decrease to some extent. Physical tests are not presented in this paper, but they will be done in the future.Den presenterade forskningen studerade fördelar och nackdelar med ett hydraulisk hjälpsystem för fordonsdrift (HAD) för en 25 meter lång timmerlastbil. Syftet var att undersöka hur drivlinans prestanda med avseende på energy, ekonomi och miljöpåverkan, påverkas av de adderade komponenterna, de hydrauliska ackumulatorerna. Hjälpsystemet är helt enkelt ett hydrostatiskt transmissionssystem. Idealt, kan bränsleförbrukning och kostnad reduceras genom att använda ackumulatorer i systemet. För att verifiera denna hypotes, har modell-baserade simuleringar utförts och resultaten har analyserats för konstantfartskörning och en körcykel med upprepade accelerationer och inbromsningar. Dessutom, har ett HAD-system med och utan ackumulator jämförts. Simuleringsresultaten visar att ett system med ackumulatorer förbrukar ca 14% mindre bränsle än ett system utan ackumulatorer. Ett ackumulatorstött system ger också 15% högre framdrivningseffekt vid accelereration. I avhandlingen dimensionera också storleken på ackumulatorerna, både teoretiskt och med simuleringar. Det finns en liten skillnad mellan resultaten från den teoretiska beräkningen och simuleringarna, som kan bero på att volymetriska förlusterna inte har tagits med i simuleringarna. En ackumulator med en storlek på 57 L visar sig ha den mest effektiva storleken för den studerade körcykeln. Vid högre körhastigheter, kommer verkningsgraden att minska till viss del. Inga fysiska tester har gjorts, men de kommer att utföras i framtiden.
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Zhechkov, Lyuben. "Simulations of the hydrogen storage capacities of carbon materials." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1193672413012-23518.
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Many methods have been proposed for efficient storage of molecular hydrogen for fuel cell applications. However, despite intense research efforts, so far, the industrial parameters of 6.5% mass ratio and 62 kg/m3 volume density are still questionable though the results are obtained by either experimentally or via theoretical simulations on reversible model systems. Carbon-based materials, have always been regarded as the most attractive physisorption substrates for the storage of hydrogen. Theoretical and experimental studies on various model carbon systems, however, failed to reach the elusive goal. In this work, it is shown that insufficiently accurate carbon - hydrogen diatomic interaction potentials, together with the neglect and incomplete treatment of the quantum effects in previous theoretical investigations, led to misleading conclusions for the absorption capacities of different carbon materials. A proper account of the contribution of quantum effects to the free energy and the equilibrium constant for hydrogen adsorption suggest that the industry specifications can be approached in a graphite-based physisorption system. The theoretical prediction can be realised by optimising the topology, the cavity shape and the accessible surface of the carbon structures.
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Alegrim, Georg, and Alexander Anaje. "Värmeåtervinning av luft i kycklingstallar : Återanvändning av energin i frånluften för luftförvärmning." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-82239.
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I Sverige har konsumtionen av kyckling per invånare ökat de senaste åren och idag konsumeras 23,2kg per person och år. Eftersom tillväxten för svensk kyckling är hög ökar också medvetenheten hos företag att investera i klimatsmarta alternativ för att minska energibehovet som leder till en minskad uppvärmningskostnad. Det valda djurstallet värms upp med en flispanna där vattenburna värmeelement förser stallet med värme längs väggarna. Syftet med studien är att undersöka hur mycket värmeenergi som går att spara genom att använda den utsugna luften för att värma den luften som sugs in med hjälp av en värmeväxlare. Det har ansetts problematiskt att använda stallets frånluft för att tillgodose energi i form av värme eftersom den oftast är dammig och detta bidrar till att filter och kanaler täpps igen. Idag finns det ett antal luftvärmeväxlare som klarar denna typ av damm och partiklar. Två olika värmeväxlare har jämförts, en rekuperativ (plattvärmeväxlare) och en regenerativ (roterande värmeväxlare). Stallet måste hålla ett lågt CO2 värde och kycklingarnas ströbädd måste hållas torr med hjälp av en låg luftfuktighet. Ventilationens volymflöde är ett beräknat teoretiskt värde. Resultatet av de två jämförda värmeväxlarna visar att den regenerativa (roterande) värmeväxlaren återför fukt vilket som bidrar till en fuktigare ströbädd jämfört med den rekuperativa (plattvärmeväxlare) som inte återför fukt. Studien genomfördes under kycklingarnas uppfödningstid, vilket varade från första januari i 34 dagar framåt. Dag 28–30 blir stallet självförsörjande på värme och värmeväxlaren kan då generera den värmen som krävs utan anläggningens tillhörande flispanna. Med hänsyn till skallklimatet är det att föredra en plattvärmeväxlare då den roterande värmeväxlaren återför vatten av tre gram per kg torr luft. Undersökningen visar det totala värmebehovet, som idag är cirka 48,2 MWh under en uppfödningsomgång, kan minskas med 24,8 MWh med hjälp av en värmeväxlare under denna omgång.The consumption of chicken per inhabitant have increased in Sweden the last couple of years and today 23,2 kg is consumed per inhabitant and year. Because of this rise of Swedish chicken consumption, the awareness of investing in climate-smart alternatives have increased by the companies. The companies are decreasing the energy required during production, which ultimately leads to a reduced heating cost. The animal stall is heated by a boiler where water-based heating elements are providing the animal stall with heat along the walls. It has been considered problematic to heat up the animal stall by reintroducing the air from inside the stall due to the fact that this air often is too dusty, which contributes to blockage of filters and ducts. There are a number of different heat exchangers that can handle this kind of dust and particles today. Two different heat exchangers will be compared, a recuperative plate heat exchanger and a regenerative rotary heat exchanger. The animal stall must keep a low CO2 value and it is important to keep the chickens bedding dry by a low humidity inside the stall. The study shows that the total heat for one breeding round, which today is approximately 48,2MWh, which equals a saving by using an air heat exchanger of 24,8MWh. The result of the comparison of the two heat exchangers has shown that the regenerative (rotary) heat exchanger reintroduces moisture in the stall, which the recuperative (plate heat exchanger) does not. The follow up for this study was 34 days, from the chickens’ birth to the slaughter. During day 28-30 the animal stall becomes self-sufficient considering heat, which means that the heat exchanger could generate the heat required for the facility without the use of the stalls chip boiler. The study is implemented with a calculated volume flow due to a short outlet channel on the system, this can lead to a risk of a minor faulty value. Regard to the humidity in the stall, it is preferable to use a plate heat exchanger as the rotating heat exchanger precipitates water of 3 grams/kg of dry air.
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Graves, Kynan E., and kgraves@swin edu au. "Electromagnetic energy regenerative vibration damping." Swinburne University of Technology, 2000. http://adt.lib.swin.edu.au./public/adt-VSWT20060307.120939.
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This thesis documents a PhD level research program, undertaken at the Industrial
Institute Swinburne, Swinburne University of Technology between the years of 1997
and 2000. The research program investigated electromagnetic energy regenerative
vibration damping; the process of recovering energy from damped, vibrating systems.
More specifically, the main research objective was to determine the performance of
regenerative damping for the application of vehicle suspension systems. This question
emerged due to the need for continuous improvement of vehicle efficiency and the
potential benefits possible from the development of regenerative vehicle suspension. It
was noted, at the outset of this research, that previous authors had undertaken research
on particular aspects of regenerative damping systems. However in this research, the
objective was to undertake a broader investigation which would serve to provide a
deeper understanding of the key factors.
The evaluation of regenerative vibration damping performance was achieved by
developing a structured research methodology that began with analysing the overall
requirements of regenerative damping and, based on these requirements, investigated
several important design aspects of the system. The specific design aspects included an
investigation of electromagnetic machines for use as regenerative damping devices. This
analysis concentrated on determining the most promising electromagnetic device
construction based on its damping and regeneration properties. The investigation then
proceeded to develop an 'impedance-matching' regenerative interface, in order to control
the energy flows in the system. This form of device had not been previously developed
for electromagnetic vibration damping, and provided a significant advantage in
maximising energy regeneration while maintaining damping control. The results from
this analysis, when combined with the issues of integrating such a system in vehicle
suspension, were then used to estimate the overall performance of regenerative damping
for vehicle suspension systems.
The methodology and findings in this research program provided a number of
contributing elements to the field, and provided an insight into the development of
regenerative vehicle systems. The findings revealed that electromagnetic regenerative
vibration damping may be feasible for applications such as electric vehicles in which
energy efficiency is a primary concern, and may have other applications in similar
vibrating systems.
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Sun, Zhifeng. "Energy Consumption Optimization of Electric Vehicles." Thesis, KTH, Fordonsdynamik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302774.
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This master thesis report has studied several methods to improve the energy consumption of an electric vehicle equipped with two permanent magnet synchronous motors. Two driving torque distribution maps are developed based on efficiency map and load transfer, respectively. The drive torque distribution map based on the efficiency map shows up to 8.94% energy saving. Two regenerative braking strategies are designed and compared. Both strategies have pure regenerative brake at low decelerations and it is controlled by a modified acceleration pedal map. Strategy 1 does not add more regenerative braking when the brake pedal is pressed thus it is simpler while strategy 2 can blend in more motor torque. Rear axle steering is also studied in terms of contribution to energy consumption and an LQR controller is developed to control the vehicle with rear axle steering.Denna rapport avhandlar ett examensarbete där flera metoder har studerats för att förbättra energikonsumptionen för ett elektriskt fordon med två permanentmagnetsynkrona motorer. Två fördelningskartor för drivande moment är framtagna baserat på effektivitetskartor och lastöverföring. Fördelningskartorna för drivande moment som är baserat på effektivitet visar upp till 8,94% energiminskning. Två olika regenerativa bromsstrategier är framtagna och jämförda. Båda strategierna har ren regeneration vid låga decelerationer och är reglerat genom modifierat gaspedalsmappning. Strategi 1 ger inte mer regeneration när bromspedalen trycks ned och är då enklare medans strategi 2 kan blanda in mer vridmoment från elmotorn. Bakaxelstyrning är också studerat i termer av dess bidrag till energikonsumption samt en LQR regulator är utvecklad för reglering av fordonets bakaxelstyrning.
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Hudson, Daniel Alexander. "Regeneration architecture." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/hudson/HudsonD0510.pdf.
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In a world of excess, people rarely stop to realize their impact on their environments. Our built environment is especially feeling the effect of our irresponsibility, and the solution is only a matter of re-wiring our perceptions of energy usage. Many technologies make it possible to have the impossible, but nobody stops to question whether or not these advances are beneficial. A presumably sustainable system turned out to be one of the most energy wasteful ones in existence. In the complex process of getting food from the field to your house, the best solution is to simplify. Nature will do most of the work; we need to learn to work with it. Current building practices can benefit greatly from this concept, to rethink the existing process by simply cutting out the unneeded steps and using the free energy available to us every day. Our values need to change. Because the corporation controls so much of our daily lives, they are the ones that will bring about the change in consciousness we desperately need. By re-designing Sysco headquarters to do everything that the company claims to do (and currently doesn't), and interact with the public in a new and radical way, not only can we make changes to how we think about the built environment, but we can also start to show that a change in awareness is entirely possible. If we can change the values of those that make the biggest differences in our world, then we've effectively changed an entire populations' way of thinking.
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Huhn, Robert. "Optimierte Wasserwärmespeicher für die Nutzung regenerativer und fossiler Energiequellen." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1200578083155-91197.
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Die Nutzung regenerativer Energiequellen stellt in vielen Systemen und Versorgungsnetzen wesentlich höhere Anforderungen an die Konstruktion, Auslegung und Betriebsführung von Wärmespeichern als konventionelle Energieträger. Aber auch das Potenzial eines Brennwertkessels kann mit einem optimierten Wasserwärmespeicher besser ausgeschöpft werden. Entscheidend für die Effizienzsteigerung von Wärmespeichern mit ausgeprägter thermischer Schichtung ist die Ausbildung und Aufrechterhaltung einer schmalen Mischzone zwischen dem wärmeren und kälteren Bereich des Speichers. Eine schmale Mischzone und eine niedrige Temperatur im unteren „entladenen“ Speicherbereich wirken sich positiv auf den Wirkungsgrad von Sonnenkollektoren und Brennwertkesseln aus. Beim Einsatz von Wärmepumpen verbessert sich deren Leistungszahl. Der Beitrag zeigt die Auswirkungen der Betriebsweise und der konstruktiven Details des Wärmespeichers, insbesondere der Be- und Entladevorrichtungen, auf, welche durch experimentelle und numerische Untersuchungen ermittelt wurdenThe spreading integration of renewable sources of energy into conventional heat supply systems places high demands on the designing, dimensioning and operation of hot water storage tanks. A pronounced thermal stratification is of positive influence for the efficiency of solar collectors, condensing boilers and the COP of heat pumps connected to the storage tank. The extent of the thermal mixing layer determines the volumetric efficiency of the tank and thus the economics of investment and operation. In this paper, a method is presented by which the losses of hot water storage tanks are correlated to the tank design and operating conditions
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Guinart, Trayter Xavier, and Aceret Jordi Orpella. "Hydraulic Regenerative System for a Light Vehicle." Thesis, Linköping University, Fluid and Mechanical Engineering Systems, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-57120.
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The thesis is based in a constructed light vehicle that must be improved by adding a hydraulic energy recovery system. This vehicle named as TrecoLiTH, participated in the Formula Electric and Hybrid competition (Formula EHI) 2009 in Italy -Rome- and won several awards.
This system consists in two hydraulic motors hub mounted which are used to store fluid at high pressure in an accumulator when braking. Through a valve the pressure will flow from the high pressure accumulator to the low pressure one, and consequently the vehicle will get extra acceleration.
This thesis consists in finishing the assembly and testing it, as the main idea was already thought and some of the necessary parts were acquired before. Firstly, a quick overview of the bike is done and the current state of it at the end of the thesis is discussed. After that, the mechanism used to actuate the system is developed and explained, with which some CAD software was used to design and make some FEA. Straight afterwards the work focused on the tests and its development. A quick discussion about what tests should be done, the preparations and also the way that some measurements were done is commented. In order to do these measurements a data acquisition device and some software to deal with it was used.
Thereupon, calculations to know if the system auto-compensates the weight added, causing more rolling resistance, and the oil frictions are done. In this part the performance and reliability of the system is discussed, as well as the feelings of the driver. Finally, improvements and possible modifications are listed with the aim of upgrade the vehicle, the system and the way of work.
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Barbu, Anca-Diana. "Investing in renewable energy sources : an assessment of non-technological issues in Central and Eastern Europe /." Hamburg : Kovač, 2007. http://www.gbv.de/dms/sub-hamburg/52588372X.pdf.
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Pires, Luisa Maria Barradas Pereira Martins. "Energy regeneration and control in vehicle suspensions." Thesis, University of Cambridge, 2014. https://www.repository.cam.ac.uk/handle/1810/265570.
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In this dissertation we propose a regenerative system that can efficiently extract energy from the suspension while improving the overall dynamical performance of the vehicle. It is shown that typical regenerative devices comprising of a linear-to-rotational element driving a permanent-magnet generator can be simply modelled as a dissipative admittance in parallel with an inerter. This configuration allows the performance benefits of inerters in vehicle suspensions to be exploited. The energy recovery circuitry is modelled as an electrical load at the generator's terminals. We propose the novel idea of designing this electrical load with the dual purpose of extracting energy from the suspension as well as acting as a passive controller designed to enhance vehicle performance. It is shown that the losses in the generator are negligible if the real-part of the electrical load is made considerably larger than the internal resistance of the permanent-magnet generator for a given frequency range. We demonstrate that the inertance, damping coefficient and energy efficiency are fundamentally related for typical regenerative devices. 'vVe then investigate how to optimise the passive electrical load at the generator's terminals for vehicle performance. 'vVe show that although the real-part constraint decreases the optimum achievable performance values for vibration isolation and grip, the added dynamical complexity leads to performance benefits when compared to typical parallel spring-damper struts. We propose to have a single dissipative element and provide the controller dynamics through a lossless transformerless coupling. Transformerless conditions are investigated for lossless two-ports. 'vVe show that paramountcy is a sufficient but not necessary condition for transformerless synthesis. We also consider the design of ladder structures when the real-part constraint is imposed in the electrical load. In this dissertation we demonstrate the feasibility of the design methodology through the design of a regenerative device for a passenger vehicle. A prototype of the device is built and tested and the deviations from ideal behaviour are found to be due to nonlinear effects such as friction and backlash. Overall a good overall agreement between the ideal and experimental admittances is obtained. Finally, we show that brushless DC motors can be used as generators, thus benefiting from their topological advantages, if they are supplied with additional power-electronics. We also propose a design of the power electronics for energy recovery.
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Grenaa, Jensen Stine. "Promoting renewable energy technologies /." Copenhagen, 2004. http://www.gbv.de/dms/zbw/394346505.pdf.
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Joo, Choonshik, and Martin Stangl. "Application of Power Regenerative Boom system to excavator." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200461.
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This paper is presenting the application of Power Regenerative Boom(PRB) system to excavator. In order to increase the fuel efficiency of the excavator, potential energy of the front structure is recuperated by the hydraulic hybrid system with electric-hydraulic control, during boom down motion. Charged energy into accumulator is reused after boom down motion, the pressurized oil goes to hydraulic motor. The hydraulic motor is mounted on the engine PTO(Power Take-Off), therefore output torque of the hydraulic motor assists the diesel engine directy, it leads to decrease fuel consumption of diesel engine. After the system design and simulation investigation, the presented system was installed into Doosan’s 38ton excavator, DX380LC-3 model, and the energy saving result was verified by a digging and dumping repetition test. The test result shows that fuel consumption was dramatically decreased by 5.0 L/hr compared to the standard DX380LC-3.
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Midgley, William John Baudinet. "Regenerative braking of urban delivery heavy goods vehicles." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607710.
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Rutledge, Matthew S. "Aircraft Gearbox Dynamics Subject to Electromechanical Actuator Regenerative Energy Flow." Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1292358176.
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Clüver, Hendrik. "Diversifikationsstrategien der Mineralölindustrie in regenerative Energie." St. Gallen, 2007. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/03605755001/$FILE/03605755001.pdf.
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Lyles, Carl Thomas. "Investigation of regenerative and alternative energy sources for electrified passenger vehicles." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54260.
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The electrification of passenger vehicles has been a step towards the reduction of greenhouse gas emissions by automobiles; however, in the United States many plug-in hybrid electric vehicles (PHEVs) and battery electric vehicles (BEVs) must still be plugged in to a grid that is heavily reliant on the burning of fossil fuels to charge. The goal of this thesis is to investigate how to develop a system capable of fully charging a PHEV using only alternative and/or regenerative energy sources.
In developing such a system, various alternative and regenerative energy sources were investigated with the intent of reaching a specified daily energy goal; sufficient to charge a PHEV. These energy sources were evaluated based upon criteria such as novelty, ability to reach desired daily energy goal, applicability to BEV/PHEV, etc. The primary technological categories considered include but are not limited to regenerative and solar technologies. The evaluation of technologies indicated that a major opportunity lies in solar technologies, and in particular concentrated photovoltaics.
Design alternatives for a concentrated photovoltaic system capable of reaching the desired energy goal are described. The design alternatives utilize Fresnel lenses as a means of concentrating a large area of sunlight onto an array of photovoltaics affixed to a vehicle. Various tracking mechanisms for the concentrating systems have been outlined to meet given design criteria. 3-D ray tracing algorithms have been developed to determine the path of the tracking mechanisms depending upon the time of year and on the geographic location. The same algorithms have been used in conjunction with typical meteorological year data to determine the expected output of the concentrating systems based upon the solar resource and solar angles at a specific place and time.
The findings suggest that a concentrated photovoltaic system designed specifically for charging an electrified vehicle may generate sufficient energy over the course of a day to power a typical driver’s trips. However, for such a concentrating system to be commercially feasible there are still many design challenges to be overcome. Design limitations and implications for further research are discussed.
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Katrini, Eleni. "Addressing food, water, waste and energy yields in urban regenerative environments." Research Showcase @ CMU, 2012. http://repository.cmu.edu/theses/55.
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“At the same time that we must respond to climate change and rising energy costs, we must also adjust our housing stock to fit a changing demographic and find more frugal form of prosperity. Such a transformation will require deep change, not just in energy sources, technology, and conservation measures but also in urban design, culture and lifestyles. More than just deploying green technologies and adjusting our thermostats, it will involve rethinking the way we live and the underlying form of our communities.” (Calthorpe, 2011)
Our cities are built dependent on centralized systems of water and waste management, food and energy production. This practice has proven efficient for a while; nonetheless as our cities expand with immense speed and population increases, severe issues of food access, waste accumulation, floods, water contamination and increased energy demand reveal the obsolescence of those systems. The solution does not lie anymore only in conservation and precautionary measures but in a diverse way of thinking and redesigning existing infrastructures. Through this thesis, several systems of urban agriculture, decentralized water management and treatment, as well as energy production from waste were identified and studied through literature and actual case studies. The ultimate goal of the research was to create a toolkit for urban regenerative environments, which will be used to introduce those systems to designers. The key component of the toolkit is the quantitative link between the spatial demands of each system and its efficiency.
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Cabrera-Codony, Alba. "Siloxane removal in the energy recovery of biogas: sequential adsorption/oxidation processes." Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/399731.
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The thesis deals with removal of organosilicon compounds in the energy recovery of biogas. Alternative adsorbents for the siloxane removal were studied, and the physical and chemical mechanisms involved in the siloxane adsorption were discovered, which improved the yield of the adsorption and regeneration technologies using both activated carbons and zeolites. Moreover, several technologies based on advanced oxidation processes have been applied in order to regenerate and reuse the exhausted adsorbents.
The thesis studies the siloxane removal at lab-scale close to real scenario conditions, including the competitive adsorption with compounds usually found in biogas, in the presence of humidity and with the same gas matrix, which allowed to select the most efficient materials for this purpose. Therefore, the knowledge reported in the thesis dissertation is directly transferable to field application to upgrade the siloxane removal systemAquesta tesi estudia l'eliminació de compostos volàtis de silici (siloxans) per la recuperació energètica del biogàs. Es van estudiar diferents adsorbents per l'adsorció de siloxans, determinants les propietats físico-químiques superficials que en condicionen l'eficiència, permetent millorar el rendiment de l'adsorció i permetent la regeneració en carbons actius i zeolites esgotats. La tesi estudia l'eliminació de siloxans a escala de laboratori en condicions properes a les reals del biogàs, incloent l'adosrció competitiva amb altres compostos orgànics volàtics, en presència d'humitat i amb diferents matrius gasoses, la qual cosa va permetre seleccionar els materials òptims per aquest propòsit.Per tant el coneixement derivat d'aquesta tesi és directament transferible per tal de millorar els sistemes d'eliminació siloxanes
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Cáceres, Delgado Adriana. "Algoritmo para frenagem regenerativa de uma máquina síncrona de imã permanente." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263011.
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Orientador: Niederauer MastelariDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
Made available in DSpace on 2018-08-16T18:46:49Z (GMT). No. of bitstreams: 1 CaceresDelgado_Adriana_M.pdf: 1925060 bytes, checksum: 9bc88ebf6480dc5a60e01e96de974f3d (MD5) Previous issue date: 2010
Resumo: A proteção ambiental e o melhor uso dos recursos energéticos são áreas de pesquisa de grande atividade. Como resultado destas pesquisas o desenvolvimento de veículos elétricos (VE) e híbridos (VEH) têm se acelerado. Estes possuem problemáticas desafiadoras, como baixa autonomia, a conversão de energia, o controle do veículo, o gerenciamento e distribuição da energia dentro dele, assim como o "design" tanto estético quanto mecânico e econômico. Este conjunto de problemáticas inspirou este projeto de mestrado que tem como objetivo o estudo e elaboração de um algoritmo para frenagem regenerativa (FR) de uma máquina síncrona de imã permanente brushless (BLDC). Motivados nas características que a estratégia de FR proporciona ao VE, entre estas, o aumento na autonomia e a melhora do desempenho mecânico e eletrônico do mesmo já que quando a FR é ativada recupera-se uma parte da energia cinética durante a desaceleração através da máquina elétrica operando como gerador. Com base no anterior este trabalho foi desenvolvido em várias etapas: principalmente ao abranger os conceitos sobre frenagem regenerativa; estudar o motor BLDC desde seu modelo, acionamento e identificação das características mais relevantes com respeito a outros motores elétricos. Seguido do projeto da parte mecânica do sistema, que compreende a transmissão e a inércia, para ser envolvidos no modelo simulado. Assim como o desenvolvimento dos algoritmos para o acionamento do motor, onde serão monitoradas a velocidade e a posição do rotor, com o fim de controlar sua aceleração e desaceleração. Posteriormente um algoritmo para frenagem regenerativa, onde é monitorado o estado do motor e executam-se as decisões lógicas tanto para redirecionamento de energia, quanto para controle da frenagem. O resultado obtido foi que o algoritmo para FR regenera parte da energia cinética envolvida durante a desaceleração, além de que gerencia o funcionamento de todo o processo e subprocessos durante a aceleração, velocidade constante e desaceleração passo a passo e minimiza o consumo de energia em cada desaceleração.
Abstract: Environmental protection and optimal energy resources are great activity research areas. As a result of these researches, electric vehicles (EVs) and hybrid (HEV) developments have been accelerated. They have challenging problems such as low autonomy, power conversion, vehicle control, energy management and distribution within it, as well as the esthetic and mechanical design and also the economic issues. This set of problems inspired this master's project which is aimed to study and elaborate an algorithm for regenerative braking (RB) in a synchronous permanent magnet brushless machine (BLDC). Motivated in the RB strategy characteristics that provides to the EV, such as, autonomy increased, mechanical and electronic performance improvement just when the RB is activated and part of the kinetic energy is recovered through the electric maquine as a generator. This work was developed in several stages: mainly cover the regenerative braking concepts; study the BLDC motor from its model, driver and outstanding features identification respect others electric motors. Followed by the mechanical design of the system, which includes the transmission and inertia, to be included in the simulated model. Just as the development of the algorithms for the motor drive, where will be monitored speed and rotor position, in order to control its acceleration and deceleration. Subsequently a management regenerative braking algorithm, which monitors the engine state, and excecute the logical decisions for redirecting the energy, and for braking control. As a result it was found that when the electrical machine operates as a generator part of the kinetic energy is recovered during deceleration. And also it was able to prove that the algorithm manages the whole process operation since the acceleration, constant velocity and deceleration step by step, while minimizing energy consumption in every downturn.
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica
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Seth, Bhartendu. "Energy regeneration and its application to active above-knee prostheses." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14911.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1987.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaves 118-121.
by Bhartendu Seth.
Ph.D.
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Samba, Murthy Aravind. "Analysis of regenerative braking in electric machines." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47660.
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All electric machines have two mechanical operations, motoring and braking. The nature of braking can be regenerative, where the kinetic energy of the rotor is converted into electricity and sent back to the power source or non-regenerative, where the source supplies electric power to provide braking. This thesis investigates several critical issues related to regenerative braking in both DC and AC electric machines, including the determination of boundaries in the torque-speed plane defining the regenerative braking capability region and the evaluation of operating points within that capability region that result in maximum regenerative braking recharge current.
Electric machines are used in the powertrains of electric and hybrid-electric vehicles to provide motoring or braking torque in response to the driver's request and power management logic. Since such vehicles carry a limited amount of electrical energy on-board their energy storage systems (such as a battery pack), it is important to conserve as much electrical energy as possible in order to increase the range of travel. Therefore, the concept of regenerative braking is of importance for such vehicles since operating in this mode during a braking event sends power back to the energy storage system thereby replenishing its energy level. Since the electric machine assists the mechanical friction braking system of the vehicle, it results in reduced wear on components within the mechanical friction brake system. As both mechanical friction braking and electric machine braking are used to provide the requested vehicle braking torque, braking strategies which relate to splitting of the braking command between the two braking mechanisms are discussed. The reduction in energy consumption of a test vehicle along different driving schedules while using different braking strategies is also studied.
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KHALAF, POYA. "Design, Control, and Optimization of Robots with Advanced Energy Regenerative Drive Systems." Cleveland State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=csu1552923998768344.
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Sensfuß, Frank. "Assessment of the impact of renewable electricity generation on the German electricity sector : an agent-based simulation approach /." Düsseldorf : VDI-Verl, 2008. http://www.gbv.de/dms/zbw/561555680.pdf.
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Floyd, William Charles. "Snowmelt energy flux recovery during rain-on-snow in regenerating forests." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42977.
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Rain-on-snow (ROS) is a major contributor to flooding and landslides in many temperate coastal watersheds around the world. Research has shown that forest harvesting can increase melt rates during ROS at both the stand and watershed scale. Because of this, post disturbance hydrological recovery is of interest in watersheds where forest management is prevalent. Recent research that pairs events by frequency rather than chronologically has indicated that forest cover removal can have a significant effect on the magnitude and frequency of extreme events, which is counter to the dominant view in forest hydrology. Hydrological modelling provides a means to apply frequency based analysis in watersheds with short data records, but models must be tested and validated in coastal watersheds before they can be applied extensively. A key challenge to testing models is the inherent difficulty with collecting data in ROS environments. Therefore, the objectives of this research were to design a methodology that recorded previously unobserved processes, use these data to validate model simulations and assess stand level energy flux recovery during ROS. Data were collected at a range of elevations within recently harvested, regenerating and old growth forests. The Cold Regions Hydrological Model generally performed well at capturing the dynamics of snow accumulation and melt, however, snow water equivalent was generally over-predicted. Depths of transient snowpacks were generally under-predicted, however, once a snowpack was established model performance improved. Clear-cut forests had higher mean and greater variability of energy inputs resulting in large events occurring more frequently than in old or second growth forests. Energy flux recovery was evident within the regenerating forests; however, both the rates of recovery and differences among stands depended on the location and the variables compared. When either the mean or standard deviation of energy inputs differed from that of old growth forests, energy flux recovery was reduced as events became larger and less frequent. It is probable that results obtained from this study will translate to stream flow in watersheds with steep slopes, shallow soils and extensive preferential flow networks (i.e. high run-off coefficients), especially when run-off generating areas are synchronized.
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Nieman, Joshua E. "A Novel, Elastically-Based, Regenerative Brake and Launch Assist Mechanism." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1399048279.
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Vujic, Nikola. "Power Regeneration in Actively Controlled Structures." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/33425.
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The power requirements imposed on an active vibration isolation system are quite important to the overall system design. In order to improve the efficiency of an active isolation system we analyze different feedback control strategies which will provide electrical energy regeneration. The active isolation system is modeled in a state-space form for two different types of actuators: a piezoelectric stack actuator and a linear electromagnetic (EM) actuator. During regenerative operation, the power is flowing from the mechanical disturbance through the electromechanical actuator and its switching drive into the electrical storage device (batteries or capacitors). We demonstrate that regeneration occurs when controlling one or both of the flow states (velocity and/or current). This regenerative control strategy affects the closed loop dynamics of the isolator which sees its damping reduced.Master of Science
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Milkau, Alexander. "Ansätze zur Förderung der erneuerbaren Energien im Wärmemarkt : eine rechtliche Bewertung des EEWärmeG und der alternativen Fördermodelle /." Baden-Baden : Nomos, 2009. http://d-nb.info/996952837/04.
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El-Samadony, Yasser Abdel Fattah. "Simulation of liquid desiccant regeneration for an energy efficient air conditioning system." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441236.
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Warner, Holly E. "Optimal Design and Control of a Lower-Limb Prosthesis with Energy Regeneration." Cleveland State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=csu1439422794.
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Nytko, Billy J. "Modeling and demonstrating regenerative braking of a squirrel cage induction motor with various deceleration rates using V by F control." Thesis, Monterey, California : Naval Postgraduate School, 2010. http://edocs.nps.edu/npspubs/scholarly/theses/2010/Jun/10Jun%5FNytko.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2010.Thesis Advisor(s): Julian, Alexander L. ; Cristi, Roberto. "June 2010." Description based on title screen as viewed on July 16, 2010. Author(s) subject terms: Regenerative Braking, dynamic braking, rheostatic braking, all electric vehicle, all electric ship. Includes bibliographical references (p. 127-128). Also available in print.
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Ursino, Welban Ricardo. "Análise e Simulação de Ciclos Térmicos Convencionais e Regenerativos para Cogeração de Bioenergia no Setor Sucroenergético /." Araraquara, 2019. http://hdl.handle.net/11449/180868.
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Orientador: Samuel Conceição de OliveiraBanca: Rondinelli Donizetti Herculano
Banca: André Ribeiro Lins de Albuquerque
Resumo: Neste estudo, realizou-se a análise da influência da pressão e da temperatura do vapor bem como da implementação de aquecedores regenerativos sobre a geração de bioenergia e a eficiência térmica (energética) em ciclos de cogeração no setor sucroenergético, considerando para priorização da geração de energia elétrica, consumo total do bagaço gerado no processo de produção de açúcar e álcool e moendas acionadas por motores elétricos. Para tanto, foram realizadas simulações dos ciclos de potência a vapor operando em diferentes condições de pressão e temperatura de vapor comumente empregadas no setor (pressão de 67 bar, em temperaturas de 490, 520 e 540°C e pressão de 100 bar à temperatura de 540°C) e temperatura da água de alimentação da caldeira variando entre 115 e 180°C, sendo a menor temperatura (115°C) aplicada em ciclos CEST (Condensing-Extraction Steam Turbine) convencional e as demais (140, 160 e 180°C) em ciclos CEST com pré-aquecedores regenerativos. Foram realizadas simulações para demandas de vapor pelo processo produtivo variando entre 380 e 460 kg/t de cana processada, em intervalos de 20 kg/t. As simulações foram baseadas em equações de conservação de massa e energia aplicadas ao sistema, as quais foram resolvidas usando-se o software Cycle-Tempo. Os resultados obtidos permitiram verificar que: (i) o aumento da temperatura e pressão de vapor proporciona um aumento na geração de energia e na eficiência energética do ciclo; (ii) a introdução de pré-aquecedores fecha... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In this study, the influence of steam pressure and temperature as well as the implementation of regenerative heaters on the bioenergy generation and thermal (energetic) efficiency in cogeneration cycles in the sucroenergy sector was analyzed. For prioritization of electric power generation, it was considered total consumption of the bagasse generated in the sugar and alcohol production process and mills activated by electric motors. For this purpose, steam power cycle simulations were performed at different pressure and vapor temperature conditions commonly used in the industry (pressure of 67 bar, at temperatures of 490, 520 and 540°C and pressure of 100 bar at a temperature of 540°C) and boiler feed water temperature ranging from 115 to 180°C, the lowest temperature (115°C) applied in conventional Condensing-Extraction Steam Turbine cycles and the other (140, 160 and 180°C) in CEST cycles with regenerative preheaters. Simulations were carried out for steam demands from the production process, varying between 380 and 460 kg/t of processed cane, at 20 kg/t intervals. The simulations were based on mass and energy conservation equations applied to the system, which were solved using the Cycle-Tempo software. The obtained results allowed to verify that: (i) the increase of the temperature and vapor pressure provides an increase on the generation of energy and the energetic efficiency of the cycle; (ii) the introduction of closed high-pressure preheaters in conventional cycles increases both the generation of electrical energy and energetic efficiency; (iii) the implementation of low pressure preheaters in cycles with high pressure preheaters...(Complete abstract click electronic access below)
Mestre
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Werner, Steffen. "Growth and Scaling during Development and Regeneration." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-208033.
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Life presents fascinating examples of self-organization and emergent phenomena. In multi-cellular organisms, a multitude of cells interact to form and maintain highly complex body plans. This requires reliable communication between cells on various length scales. First, there has to be the right number of cells to preserve the integrity of the body and its size. Second, there have to be the right types of cells at the right positions to result in a functional body layout. In this thesis, we investigate theoretical feedback mechanisms for both self-organized body plan patterning and size control. The thesis is inspired by the astonishing scaling and regeneration abilities of flatworms. These worms can perfectly regrow their entire body plan even from tiny amputation fragments like the tip of the tail. Moreover, they can grow and actively de-grow by more than a factor of 40 in length depending on feeding conditions, scaling up and down all body parts while maintaining their functionality. These capabilities prompt for remarkable physical mechanisms of pattern formation. First, we explore pattern scaling in mechanisms previously proposed to describe biological pattern formation. We systematically extract requirements for scaling and highlight the limitations of these previous models in their ability to account for growth and regeneration in flatworms. In particular, we discuss a prominent model for the spontaneous formation of biological patterns introduced by Alan Turing. We characterize the hierarchy of steady states of such a Turing mechanism and demonstrate that Turing patterns do not naturally scale. Second, we present a novel class of patterning mechanisms yielding entirely self-organized and self-scaling patterns. Our framework combines a Turing system with our derived principles of pattern scaling and thus captures essential features of body plan regeneration and scaling in flatworms. We deduce general signatures of pattern scaling using dynamical systems theory. These signatures are discussed in the context of experimental data. Next, we analyze shape and motility of flatworms. By monitoring worm motility, we can identify movement phenotypes upon gene knockout, reporting on patterning defects in the locomotory system. Furthermore, we adapt shape mode analysis to study 2D body deformations of wildtype worms, which enables us to characterize two main motility modes: a smooth gliding mode due to the beating of their cilia and an inchworming behavior based on muscle contractions. Additionally, we apply this technique to investigate shape variations between different flatworm species. With this approach, we aim at relating form and function in flatworms. Finally, we investigate the metabolic control of cell turnover and growth. We establish a protocol for accurate measurements of growth dynamics in flatworms. We discern three mechanisms of metabolic energy storage; theoretical descriptions thereof can explain the observed organism growth by rules on the cellular scale. From this, we derive specific predictions to be tested in future experiments. In a close collaboration with experimental biologists, we combine minimal theoretical descriptions with state-of-the-art experiments and data analysis. This allows us to identify generic principles of scalable body plan patterning and growth control in flatwormsDie belebte Natur bietet uns zahlreiche faszinierende Beispiele für die Phänomene von Selbstorganisation und Emergenz. In Vielzellern interagieren Millionen von Zellen miteinander und sind dadurch in der Lage komplexe Körperformen auszubilden und zu unterhalten. Dies verlangt nach einer zuverlässigen Kommunikation zwischen den Zellen auf verschiedenen Längenskalen. Einerseits ist stets eine bestimmte Zellanzahl erforderlich, sodass der Körper intakt bleibt und seine Größe erhält. Anderseits muss für einen funktionstüchtigen Körper aber auch der richtige Zelltyp an der richtigen Stelle zu finden sein. In der vorliegenden Dissertation untersuchen wir beide Aspekte, die Kontrolle von Wachstum sowie die selbstorganisierte Ausbildung des Körperbaus. Die Dissertation ist inspiriert von den erstaunlichen Skalierungs- und Regenerationsfähigkeiten von Plattwürmern. Diese Würmer können ihren Körper selbst aus winzigen abgetrennten Fragmenten -wie etwa der Schwanzspitze- komplett regenerieren. Darüberhinaus können sie auch, je nach Fütterungsbedingung, um mehr als das 40fache in der Länge wachsen oder schrumpfen und passen dabei alle Körperteile entsprechend an, wobei deren Funktionalität erhalten bleibt. Diese Fähigkeiten verlangen nach bemerkenswerten physikalischen Musterbildungsmechanismen. Zunächst untersuchen wir das Skalierungsverhalten von früheren Ansätzen zur Beschreibung biologischer Musterbildung. Wir leiten daraus Voraussetzung für das Skalieren ab und zeigen auf, dass die bekannten Modelle nur begrenzt auf Wachstum und Regeneration von Plattwürmern angewendet werden können. Insbesondere diskutieren wir ein wichtiges Modell für die spontane Entstehung von biologischen Strukturen, das von Alan Turing vorgeschlagen wurde. Wir charakterisieren die Hierarchie von stationären Zuständen solcher Turing Mechanismen und veranschaulichen, dass diese Turingmuster nicht ohne weiteres skalieren. Daraufhin präsentieren wir eine neuartige Klasse von Musterbildungsmechanismen, die vollständig selbstorgansierte und selbstskalierende Muster erzeugen. Unser Ansatz vereint ein Turing System mit den zuvor hergeleiteten Prinzipien für das Skalieren von Mustern und beschreibt dadurch wesentliche Aspekte der Regeneration und Skalierung von Plattwürmern. Mit Hilfe der Theorie dynamischer Systeme leiten wir allgemeine Merkmale von skalierenden Mustern ab, die wir im Hinblick auf experimentelle Daten diskutieren. Als nächstes analysieren wir Form und Fortbewegung der Würmer. Die Auswertung des Bewegungsverhaltens, nachdem einzelne Gene ausgeschaltet wurden, ermöglicht Rückschlüsse auf die Bedeutung dieser Gene für den Bewegungsapparat. Darüber hinaus wenden wir eine Hauptkomponentenanalyse auf die Verformungen des zweidimensionalen Wurmkörpers während der natürlichen Fortbewegung an. Damit sind wir in der Lage, zwei wichtige Fortbewegungsstrategien der Würmer zu charakterisieren: eine durch den Zilienschlag angetriebene gleichmässige Gleitbewegung und eine raupenartige Bewegung, die auf Muskelkontraktionen beruht. Zusätzlich wenden wir diese Analysetechnik auch an, um Unterschiede in der Gestalt von verschiedenen Plattwurmarten zu untersuchen. Grundsätzlich zielen alle diese Ansätze darauf ab, das Aussehen der Plattwürmer mit den damit verbundenen Funktionen verschiedener Körperteile in Beziehung zu setzen. Schlussendlich erforschen wir den Einfluss des Stoffwechsels auf den Zellaustausch und das Wachstum. Dazu etablieren wir Messungen der Wachstumsdynamik in Plattwürmern. Wir unterscheiden drei Mechanismen für das Speichern von Stoffwechselenergie, deren theoretische Beschreibung es uns ermöglicht, das beobachtete makroskopische Wachstum des Organismus mit dem Verhalten der einzelnen Zellen zu erklären. Basierend darauf leiten wir Vorhersagen ab, die nun experimentell getestet werden. In enger Zusammenarbeit mit Kollegen aus der experimentellen Biologie führen wir minimale theoretische Beschreibungen mit modernsten Experimenten und Analysetechniken zusammen. Dadurch sind wir in der Lage, Grundlagen sowohl der skalierbaren Ausbildung des Körperbaus als auch der Wachstumskontrolle bei Plattwürmern herauszuarbeiten
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Schermeyer, Hans [Verfasser], and W. [Akademischer Betreuer] Fichtner. "Netzengpassmanagement in regenerativ geprägten Energiesystemen / Hans Schermeyer ; Betreuer: W. Fichtner." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1169212271/34.
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Hänninen, Henri, Jyri Juhala, Jyrki Kajaste, and Matti Pietola. "Hydraulic Energy Recovery System Utilizing a Thermally Regenerative Hydraulic Accumulator Implemented to a Reach Truck." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199901.
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The implementation of an energy recovery system for retreiving otherways wasted energy is an effective method for reducing the overall energy consumption of a mobile machine. In a fork lift, there are two subsystems that can be effectively modified for recovering energy. These are the driveline and the lift/lower function of the mast. This study focuses on the latter by studying a recovery system whose main component is a hydraulic transformer consisting of a hydraulic motor, a variable displacement pump and an induction motor. Since the flow rate/pressure - ratio can be modified, the utilization of the hydraulic transformer enables downsizing of the accumulator volume. However, the decrease of the gas volume leads to an increase in the compression ratio of the accumulator, which in terms leads to higher gas temperatures after charging and consequently to higher thermal losses during holding phase. In order to reduce these losses, a thermally regenerative unit was implemented to the gas volume of an accumulator to reduce the temperature build up during charging. In this study, the effect of improving the thermal characteristics of the accumulator to the efficiency of the whole energy recovery system is investigated by means of measurements.
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Sato, Seiji. "Energy Metabolism and Regeneration in Transgenic Mouse Liver Expressing Creatine Kinase after Major Hepatectomy." Kyoto University, 1997. http://hdl.handle.net/2433/202185.
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Kyoto University (京都大学)0048
新制・課程博士
博士(医学)
甲第6768号
医博第1868号
新制||医||661(附属図書館)
15840
UT51-97-H152
京都大学大学院医学研究科外科系専攻
(主査)教授 今村 正之, 教授 中西 重忠, 教授 西川 伸一, 教授 山岡 義生
学位規則第4条第1項該当
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Sjöholm, Mikael. "Benefits of regenerative braking and eco driving for high-speed trains : Energy consumption and brake wear." Thesis, KTH, Spårfordon, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-31701.
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on mechanical brakes. The electric regenerative brakes can thus be used as normal service brake with minimum time loss.The first part of the study aims at developing a method to calculate wear on train brake pads. This is done by using a reformulated version of Archard’s wear equation with a temperature dependent wear coefficient and a temperature model to predict the brake pad temperature during braking. The temperature model is calibrated using trustworthy data from a brake system supplier and full-scale test results.By performing simulations in the program STEC (Simulation of Train Energy Consumption), energy consumption for different cases of high-speed train operations is procured and significant data for the wear calculations are found. Simulations include both “normal driving techniques” and “eco driving”. The driving styles were decided through interviews with train drivers and experts on energy optimized driving systems.The simulations show that more powerful drive systems reduce both energy consumption and travel time by permitting higher acceleration and energy regeneration while braking. Calculations show that since the electric motors could carry out more of the braking the wear of the mechanical brakes becomes lower.Eco driving techniques can help to further reduce the energy consumption and mechanical brake wear. This driving style can require some time margins though, since it takes slightly longer time to drive when using coasting and avoiding speed peaks. However, if used properly this should not have to affect the actual travel time, partly because some time margins are always included in the timetable.Even if new, more powerful, trains would have the ability to reduce energy consumption and brake wear it is also necessary to have an appropriate slip control system for the electric brakes, making it possible to use them also under slippery conditions. In this context it is important that the adhesion utilization is modest, about 12 – 15 % for speeds up to 100 km/h and lower at higher speeds.
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Bao, Ran. "The architecture of pneumatic regenerative systems for the diesel engine." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/21267.
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For vehicles whose duty cycle is dominated by start-stop operation, fuel consumption may be significantly improved by better management of the start-stop process. Pneumatic hybrid technology represents one technology pathway to realise this goal. Vehicle kinetic energy is converted to pneumatic energy by compressing air into air tank(s) during the braking. The recovered air is reused to supply an air starter, or supply energy to the air path in order to reduce turbo-lag. This research aims to explore the concept and control of a novel pneumatic hybrid powertrain for a city bus application to identify the potential for improvements in fuel economy and drivability. In order to support the investigation of energy management, system architecture and control methodologies, two kinds of simulation models are created. Backward-facing simulation models have been built using Simulink. Forward-facing models have been developed in the GT-POWER and Simulink co-simulation. After comparison, the fully controllable hybrid braking system is chosen to realize the regenerative braking function. A number of architectures for managing a rapid energy transfer into the powertrain to reduce turbo-lag have been investigated. A city bus energy control strategy has been proposed to realize the Stop-Start Function, Boost Function, and Regenerative Braking Function as well as the normal operations. An optimisation study is conducted to identify the relationships between operating parameters and respectively fuel consumption, performance and energy usage. In conclusion, pneumatic hybrid technology can improve the city bus fuel economy by at least 6% in a typical bus driving cycle, and reduce the engine brake torque response and vehicle acceleration. Based on the findings, it can be learned that the pneumatic hybrid technology offers a clear and low-cost alternative to the electric hybrid technology in improving fuel economy and vehicle drivability.
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Meise, Philipp T. "Energy flow in regenerative braking for road vehicles : the analysis of braking and acceleration energy flows in a vehicle with regenerative braking for the prediction of fuel savings and the design of system components for effective capacity utilization." Thesis, University of Bradford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633056.
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Silva, Rui Manuel Ramos da. "Soluções sustentáveis no transporte vertical. A travagem regenerativa." Master's thesis, Instituto Superior de Economia e Gestão, 2012. http://hdl.handle.net/10400.5/10346.
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Mestrado em Gestão e Estratégia IndustrialA procura pela eficiência energética tornou-se uma responsabilidade de todos. Seja por questões ambientais, pelo escasseio de combustíveis fósseis, por cumprimento de legislações, pela procura de competitividade ou apenas pela busca de poupança é notória a insistência na utilização racional de energia, na poupança energética e na consciencialização ambiental. As empresas tentam a todo o custo encontrar soluções para fazer face a este problema e assim se manterem competitivas. Porém, a ideia de um produto inovador por si só não é suficiente para lançá-lo com sucesso no mercado existindo um trabalho importante a ser realizado antecedentemente. A presente tese tem como primeiro objetivo focar a Análise de Valor e o Teste de Conceito como duas metodologias chave para o desenvolvimento de um produto/inovação em colaboração com o cliente, de modo a satisfazer as suas necessidades pelo custo mais baixo. A inovação escolhida foi a travagem regenerativa associada ao transporte vertical permitindo a geração de energia com injeção de potência na rede contribuindo assim para a eficiência energética nos edifícios. O segundo objetivo passa por determinar a existência ou não de regeneração de energia, em que condições e quantidades tal acontece sendo para isso realizados testes práticos numa instalação real.
The energy efficiency demand has become a shared responsibility. Whether for the environmental issues, the fossil fuels extinction, the laws compliance, the competitiveness search or just for the energy saving target, it is notorious the insistence on the rational use of energy, on the energy saving and on the environmental awareness. The companies try at all costs to find solutions to tackle this problem and to remain competitive. But just an innovative product idea is not enough to throw it successfully in the market and there is a significant work to be done antecedently. The first target of this thesis is to focus the Value Analysis and Concept Testing as two key methodologies for the product/innovation development in collaboration with the client to satisfy their needs at lower cost. The chosen innovation was the regenerative braking associated to the vertical transport allowing the power generation with power injection to the electric network contributing to the energy efficiency in buildings. The second objective is to determine the energy regeneration existence or not, on what conditions and quantities it happens. For that purpose it were made practical tests in a real installation.
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Bakhiet, Arig G. "Investigation of Agricultural Residues Gasification for Electricity Production in Sudan as an Example for Biomass Energy Utlization under Arid Climate Conditions in Developing Countries." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1211207352814-40782.
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This study examines the possibility of electricity production through gasification of agricultural residues in Sudan. The study begins in Chapter 1, by providing general contextual analysis of the energy situation (production and consumption patterns) in Sudan with specific focus on electricity. It proceeded to study the potential of Petroleum, Biomass and other renewable sources for electricity production. Dramatic increase in electricity production was found to be essential especially through decentralised power plants as the current electricity production services cover ~ 13 % of the population of Sudan. Biomass potential in Sudan justifies the use of agricultural residues as energy source; its potential was estimated by ~ 350000 TJ/a. Further, the urban centres of arid regions in western Sudan were identified as the target group for this study. In chapter 2, specific investigations for selected study area through field work using statistical tools such as questionnaires, interviews and field observation show that income is highly correlated to electricity consumption. The flat rate system did not result in higher consumption thus the assumption that this consumption will not drastically change in the next 10 years could be accepted. As orientation value for BGPP, 8000 tons of GN.S are available annually, the average electricity consumption is ~ 4 kWh/day/family while acceptable price could be 40 SDD/kWh (0.15 €). In chapter 3, literature review was carried to spot out the comparative merits of the gasification technology and the most optimum gasifying and electricity production system. As a result downdraft gasifier and ICE were suggested as suitable systems. In chapter 4, fuel properties and fuel properties of agricultural residues were studied, different samples were tested and the results were presented. The main conclusions derived were: fuel properties of agricultural residues are modifiable properties, so utlization planning is possible as for any other energy resource. In Sudan, Baggase, Groundnuts shells and Roselle stalks could be considered as possible fuels. The experimental work done in chapter 5 showed that GN.S could be gasified in down draft gasifiers, which are less costly and simpler to operate than circulating systems. Acceptable values of gas thermal properties (c.v.~ 4 MJ/Nm3, 30 % of burnable gases) at fairly continuing processes were obtained. In chapter 6, a concept for biomass power plant was drafted, the main components are: downdraft, air based gasifier connected to ICE, multi-stage gas cleaning system (cyclones, washer and filters) mechanical ash removal and semi closed water cycle. Main operation measures are: electricity is the sole product; working time is 150 day/year between mid Novembermid Mars. Environmental hazards of waste management e.g. flue gas emission and waste water management are the limiting factors. In the last part of chapter 6 an economic analysis was carried out. At a value of 3000 €/kW for the initial system and fuel price of 100000 €/year for ~6 GWh then a price of 0.23 €/kWh and a return period of 24 years could be obtained. The study concludes in chapter 7 that biomass gasification under the local conditions has its comparative merits however a high institutional support is needed at the beginningDiese Studie untersucht die Möglichkeit der Elektrizitätsproduktion durch Vergasung von landwirtschaftlichen Abfällen im Sudan. Die Untersuchung beginnt im Kapitel 1 mit der Bereitstellung einer allgemeinen zusammenhängenden Analyse der Energiesituation (Produktions- und Verbrauchsmuster) im Sudan mit dem besonderen Fokus auf Elektrizität, gefolgt von einer Studie des Potentials von Petroleum, Biomasse und anderer erneuerbarer Quellen für die Produktion von Elektrizität. Eine starke Zunahme bei der Elektrizitätsproduktion wurde als nötig bewertet, da dezentrale Kraftwerke, als die gegenwärtigen Elektrizitätsproduktionsbetriebe, nur die Versorgung von 13 % der Bevölkerung im Sudan abdecken. Das geschätzte Potential der landwirtschaftlichen Abfälle liegt bei ca. 350.000 TJ/Jahre damit kommen sie als Energiequelle in Frage. Weiterhin wurden urbane Zentren der ariden Regionen in Westsudan als Zielgruppe für die Untersuchung ausgewählt. In Kapitel 2 werden detaillierte Untersuchungen für das ausgewählte Studiengebiet durch Feldstudien unter Verwendung von statistischen Werkzeugen, wie Fragebögen, Interviews und Felduntersuchungen dargestellt. Das Ergebnis zeigt, dass das Einkommen im höchsten Maße mit dem Elektrizitätsverbrauch korreliert ist. Das Flat rate System hatte keinen höheren Verbrauch zur Folge, folglich kann die Annahme akzeptiert werden, dass sich der Verbrauch in den nächsten 10 Jahren nicht drastisch ändern wird. Als Orientierungswert für Biomasse Kraftwerk: 8.000 t/Jahr Erdnussschalen sind verfügbar. Der durchschnittliche Elektrizitätsverbrauch beträgt ca. 4 kWh/Tag/Familie betrachtet für 10.000 Familien. Im Kapitel 3 wird eine Literaturrecherche für die Vergasungstechnologie durchgeführt, zum Vergleich ihrer Vorteile und zur Auswahl des optimalen Vergasungs- und Gasumwandlungssystems. Als Ergebnis wurden der Festbett-Gleichstrom-Vergaser und gas Motor als passende Systeme vorgeschlagen. In Kapitel 4 werden Brennstoff Eigenschaften von landwirtschaftlichen Abfällen untersucht, verschiedene Proben getestet und die Ergebnisse präsentiert. Die Hauptschlussfolgerung daraus ist: Brennstoff Eigenschaften von landwirtschaftlichen Abfällen sind veränderbare Eigenschaften, welche eine bessere Planung erlauben und somit ihre Verwendung favorisieren. Im Sudan können Bagasse, Erdnussschalen und Rosellenstiele als optimaler Brennstoff gelten. Die experimentelle Arbeit in Kapitel 5 zeigt, dass Erdnussschalen im 75 kW Festbett-Gleichstrom-Systemen vergast werden können, welche weniger kostenintensiv und einfach zu bedienen sind als zirkulierende Systeme. Akzeptable Werte der Gaseigenschaften (c.v. ca. 4 MJ/Nm³, 35 % von brennbaren Gasen) wurden in kontinuierlichen Prozessen erreicht. In Kapitel 6 wurde ein Konzept für Biomassekraftwerke entworfen. Deren Hauptkomponenten sind: Festbett-Gleichstrom-Vergaser in Verbindung mit ICE, mehrstufige Gasreinigungssysteme (Zyklone, Wäscher und Filter), mechanische Aschensysteme und ein teilweise geschlossener Wasserkreislauf. Hauptbetriebsmaßnahmen sind: Elektrizität als das einzige Produkt, die Arbeitszeit beträgt 150 Tage pro Jahr zwischen November und April. Umweltrisiken des Abfallmanagements z.B. Rauchgas und Abwassermanagement sind die limitierenden Faktoren. Im letzten Teil von Kapitel 6 wurde eine ökonomische Analyse durchgeführt. Ein Wert von 3000 €/kW für das Anfangssystem und ein Kraftstoffpreis von 100.000 €/Jahr für 6 GWh dann ein Preis von 0,23 €/kWh und eine Amortisationszeit von 24 Jahren können angenommen werden. Die Studie schlussfolgert, dass die Vergasung unter den Bedingungen des Studiengebietes ihre Vorteile hat, jedoch ist institutionelle Unterstützung am Anfang nötig
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Baumung, Tilo, and Guntram Buchheim. "Entwicklung und Demonstration eines neuartigen Prozesses (Konvektionsgenerator) zur Stromerzeugung aus niederenthalper Wärme." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1237544922800-32933.
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Aus Thermalwässern mit Temperaturen nur wenig über der Kühltemperatur ist die Stromgewinnung bisher nicht wirtschaftlich. Ein neuartiger Konvektionsgenerator soll das ändern. Er lässt sich auch für insustrielle Rest- oder Abwärme einsetzen.
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Paul, Jeena. "Study of Energy Neutrality in Kochi Metro Rail, India." Thesis, Högskolan i Halmstad, Sustainability, Innovation and Management in Building (SIMB), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-44588.
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Now a days, the society thinks about more sustainable and clean energy sources. Most of the countries in the world relay on non-renewable energy sources for the generation of electricity. This results in the scarcity of fossil fuels in future and also increases the production of carbon emissions. This thesis considers a metro system named Kochi Metro which is a rapid transit system serving in the city of Kochi in Kerala, India which uses renewable sources, mainly solar, for giving power to the Metro.In this thesis work, trying to analyze the measures adopted by Kochi Metro Rail project in potential reductions of energy consumption and energy generation both contributing to energy efficiency.With the help of Matlab, different levels of installed PV power are used to find out the possible self-usage, self-sufficiency, and energy neutrality of the system.
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Grimm, Benjamin Mihuta. "Modeling and Analysis of Crankshaft Energy Harvesting for Vehicle Fuel Economy Improvement." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1339685318.
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Pomilio, José Antenor 1960. "Frenagem regenerativa de maquina CC acionada por recortador : maximização da energia regenerada." [s.n.], 1986. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261937.
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Orientador: Alvaro Geraldo Badan PalharesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica
Made available in DSpace on 2018-07-15T17:17:12Z (GMT). No. of bitstreams: 1 Pomilio_JoseAntenor_M.pdf: 9468816 bytes, checksum: 273f16c4bb5d49cf4076c3209344ed44 (MD5) Previous issue date: 1986
Resumo: Não informado
Abstract: Not informed.
Mestrado
Mestre em Engenharia Elétrica
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Guedes, Paulo André da Matta. "Sistema regenerativo de energia com alto rendimento e fator de potência unitário." Florianópolis, SC, 2000. http://repositorio.ufsc.br/xmlui/handle/123456789/79160.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.Made available in DSpace on 2012-10-17T23:52:41Z (GMT). No. of bitstreams: 0Bitstream added on 2014-09-25T18:44:00Z : No. of bitstreams: 1 176593.pdf: 3385811 bytes, checksum: aec7cf7e8ff04b76862fa140b157af41 (MD5)
Este trabalho se concentrou na andlise, simulagdo e experimentagdo de um inversor em ponte completa para realizar o teste de burn-in de reatores eletr6nicos utilizando-se o concerto de reciclagem de potência. A estrutura proposta substitui o banco de resistores, que tradicionalmente é utilizado pelos fabricantes neste tipo de teste, drenando a corrente de carga exigida, mas apresentando a vantagem de que a maior parte da energia devolvida para a rede. A corrente devolvida para a rede apresenta baixa taxa de distorção harmonica e alto fator de potência. Dessa forma, o teste pode ser realizado com um consumo bem menor de energia elétrica. Finalmente concluiu-se que a reciclagem de potência aplicada ao teste de burn-in de reatores eletrônicos mostrou-se bastante atraente tanto sob o aspecto econômico como também ecológico, seguindo a tendência atual da busca de otimização no uso dos recursos energéticos disponiveis.
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Herholz, Ute. "Wachstumspotentiale erneuerbarer Energien und ihre Implikationen für Klimaschutz, Versorgungssicherheit und Wettbewerbsfähigkeit /." Frankfurt a. M. [u.a.] : Lang, 2006. http://www.gbv.de/dms/zbw/51615155X.pdf.
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Fournier, David. "Metro regenerative braking energy : optimization through rescheduling : mathematical model and greedy heuristics compared to MILP and CMA-ES." Paris 7, 2014. http://www.theses.fr/2014PA077144.
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The use of regenerative braking is a key factor to reduce the energy consumption of a metro line. In the case where no device can store the energy produced during braking, only the metros that are accelerating at the same time can benefit from it. Maximizing the power transfers between accelerating and braking metros thus provides a simple strategy to benefit from regenerative energy without any other hardware device. In this thesis, we use a mathematical timetable model to classify various metro energy optimization rescheduling problems studied in the literature and prove their NP-hardness by polynomial reductions of SAT. We then focus on the problem of minimizing the global energy consumption of a metro timetable by modifying the dwell times in stations. We present a greedy heuristic algorithm which aims at locally synchronizing braking metros along the timetable with accelerating metros in their time neighbourhood, using a non-linear approximation of energy transfers. On a benchmark of six small size timetables, we show that our greedy heuristics performs better than CPLEX using a MILP formulation of the problem, even when it is able to prove the optimality of a linear approximation of the objective function. We also show that it runs ten times faster than a state-of-the-art evolutionary algorithm, called the covariance matrix adaptation evolution strategy (CMA-ES), using the same non-linear objective function on these small size instances. On real data leading to 10000 decision variables on which both MILP and CMA-ES do not provide solutions, the dedicated algorithm of our thesis computes solutions with a reduction of energy consumption ranging from 5% to 9%The use of regenerative braking is a key factor to reduce the energy consumption of a metro line. In the case where no device can store the energy produced during braking, only the metros that are accelerating at the same time can benefit from it. Maximizing the power transfers between accelerating and braking metros thus provides a simple strategy to benefit from regenerative energy without any other hardware device. In this thesis, we use a mathematical timetable model to classify various metro energy optimization rescheduling problems studied in the literature and prove their NP-hardness by polynomial reductions of SAT. We then focus on the problem of minimizing the global energy consumption of a metro timetable by modifying the dwell times in stations. We present a greedy heuristic algorithm which aims at locally synchronizing braking metros along the timetable with accelerating metros in their time neighbourhood, using a non-linear approximation of energy transfers. On a benchmark of six small size timetables, we show that our greedy heuristics performs better than CPLEX using a MILP formulation of the problem, even when it is able to prove the optimality of a linear approximation of the objective function. We also show that it runs ten times faster than a state-of-the-art evolutionary algorithm, called the covariance matrix adaptation evolution strategy (CMA-ES), using the saure non-linear objective function on these small size instances. On real data leading to 10000 decision variables on which both MILP and CMA-ES do not provide solutions, the dedicated algorithm of our thesis computes solutions with a reduction of energy consumption ranging from 5% to 9%