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1
Isevall, Holmlund Lovisa. "Increasing transport efficiency at OKG." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112091.
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Detta arbete är utfört på uppdrag av OKG AB som äger Oskarshamnsverket där verksamheten består av elproduktion i form av kärnkraft. Syftet med arbetet är att se över möjligheter företaget har att effektivisera transportlogistiken på industriområdet. För att hitta effektiviseringspotential ingick en flödeskartläggning av transporterna på det inre området, att analysera flaskhalsar samt förändringar företaget kan införa för att nå förbättringar kring transportverksamheten. Det första delmomentet i arbetet bestod av att ta fram en grund till utredningen i form av en teoretisk referensram samt att göra en kartläggning av företaget. Vidare bestod det andra delmomentet av att skapa en simuleringsmodell baserat på det verkliga transportsystemet och därefter göra utredningar med hjälp av modellen för att ta fram förbättringsförslag till OKG. Transportverksamheten hos OKG har potential att förbättras och effektiviseras genom att i avtalet med ISS minska kravet på antal fordon som ska tillhandahållas. Med en efterfrågan som i nulägesmodellen skulle transporterna vara möjliga att leverera med två fordon i stället för tre, vilket även resulterar i en högre utnyttjandegrad. Om efterfrågan ökar med upp till 20 % i jämförelse med nulägesmodellen som använts räcker två transportfordon och har då dessutom felmarginal. Skulle efterfrågan öka med 50 % eller mer krävs tre fordon för att kunna utföra alla transporter. En möjlighet till att effektivisera transportlogistiken hos OKG är genom att minska väntetiderna vid portöppningar hos reaktorbyggnaderna, detta kan göras till exempel genom att arbeta fram tydligare och effektivare rutiner. Med minskade väntetider minskar utnyttjandegraden och frigör resurser. Den största flaskhalsen som identifierats är informationsflödet och informationshanteringen. En metod för informationshantering kring de transporter som utförs på området bör tas fram. Utan tillräcklig information kan inte en fullständig utredning om transportverksamheten utföras. Vid själva utförandet av transporter är väntetiderna kring portöppningar den största flaskhalsen.
2
Hart, John. "Increasing manufacturing efficiency within a simulation environment." Thesis, University of Sunderland, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261571.
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Uppal, Amit. "Increasing the efficiency of network interface card." Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-10282007-162402.
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Morgan, Wiley Spencer. "Increasing the Computational Efficiency of Combinatoric Searches." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6528.
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A new algorithm for the enumeration of derivative superstructures of a crystal is presented. The algorithm will help increase the efficiency of computational material design methods such as cluster expansion by increasing the size and diversity of the types of systems that can be modeled. Modeling potential alloys requires the exploration of all possible configurations of atoms. Additionally, modeling the thermal properties of materials requires knowledge of the possible ways of displacing the atoms. One solution to finding all symmetrically unique configurations and displacements is to generate the complete list of possible configurations and remove those that are symmetrically equivalent. This approach, however, suffers from the combinatoric explosion that happens when the supercell size is large, when there are more than two atom types, or when atomic displacements are included in the system. The combinatoric explosion is a problem because the large number of possible arrangements makes finding the relatively small number of unique arrangements for these systems impractical. The algorithm presented here is an extension of an existing algorithm [Hart & Forcade (2008a), Hart & Forcade (2009a), Hart et al. (2012a) Hart, Nelson, & Forcade] to include the extra configurational degree of freedom from the inclusion of displacement directions. The algorithm makes use of another recently developed algorithm for the Pólya [Pólya & Read (1987), Pólya (1937), Rosenbrock et al.(2015) Rosenbrock, Morgan, Hart, Curtarolo, & Forcade] counting theorem to inform the user of the total number of unique arrangements before performing the enumeration and to ensure that the list of unique arrangements will fit in system memory. The algorithm also uses group theory to eliminate large classes of arrangements rather than eliminating arrangements one by one. The three major topics of this paper will be presented in this order, first the Pólya algorithm, second the new algorithm for eliminating duplicate structures, and third the algorithms extension to include displacement directions. With these tools, it is possible to avoid the combinatoric explosion and enumerate previously inaccessible systems, including those that contain displaced atoms.
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Hartley, Thomas Noel. "Increasing the potassium use efficiency of crops." Thesis, University of York, 2017. http://etheses.whiterose.ac.uk/20019/.
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Increasing the potassium use efficiency (KUE) of crops will be important in satisfying growing demand for food that is cost-effective and has minimal environmental consequences. The work presented in this thesis contributes to this aim by exploring the measurement of KUE and identifying drivers responsible for differences in KUE between rice genotypes at the physiological and genetic levels. In Chapter 2, a mathematical model was constructed based on growth experiments using cv. IR64 rice plants. Subsequently, sensitivity analysis was used to assess how best to measure KUE experimentally, showing how KUE could be comprehensively measured using a small selection of metrics. KUE was then quantified in over 300 rice genotypes in Chapter 3. From this, high performing rice genotypes were identified along with associations between KUE metrics and physiological traits. While key physiological drivers of differences between genotypes differed with metrics, the replacement of potassium by sodium was consistently found to aid KUE. In Chapter 4, differences in KUE between rice genotypes were then explored at the genetic level, using genome-wide association studies (GWAS) to describe the genetic underpinnings of KUE for the first time. This resulted in the identification of KUE-relevant quantitative trait loci (QTLs) and candidate genes. Both novel and previously described QTLs for KUE were found and links between the sub-population structure present in rice and the genetic architecture of KUE were uncovered. Furthermore, several genes coding for proteins with regulatory functions were identified in GWAS analyses, as were genes for sodium transport proteins. Taken together, the findings of the work presented in this thesis could be used to inform future KUE studies as well as providing candidate physiological traits and genetic loci for crop improvement.
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Clough, Andrew Lawrence. "Increasing adder efficiency by exploiting input statistics." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42424.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2008.Includes bibliographical references (p. 49-50).
Current techniques for characterizing the power consumption of adders rely on assuming that the inputs are completely random. However, the inputs generated by realistic applications are not random, and in fact include a great deal of structure. Input bits are more likely to remain in the same logical states from addition to addition than would be expected by chance and bits, especially the most significant bits, are very likely to be in the same state as their neighbors. Taking this data, I look at ways that it can be used to improve the design of adders. The first method I look at involves looking at how different adder architectures respond to the different characteristics of input data from the more significant and less significant bits of the adder, and trying to use these responses to create a hybrid adder. Unfortunately the differences are not sufficient for this approach to be effective. I next look at the implications of the data I collected for the optimization of Kogge- Stone adder trees, and find that in certain circumstances the use of experimentally derived activity maps rather than ones based on simple assumptions can increase adder performance by as much as 30%.
by Andrew Lawrence Clough.
M.Eng.
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Kubickas, Andrius. "Increasing Of Production Efficiency In Metal Processing Companies." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100628_093043-55796.
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In the final of magistral work I investigate increase of efficiency of industrial companies. I am mostly
concentrated in creation of model for increase of efficiency of manufacturing. That will mostly be appropriate for
industrial companies that are specialized in metal manufacturing and welding.
In the first part analysis of scientific – methodic literature on theme of manufacturing efficiency increase is
described by me including the essential notions. I have investigated various aspects of manufacturing
organization. I have deepen in principles of possession of manufacturing and have analyzed principles of selection
of Lean tools paying attention on criteria set in companies.
In the second part information about surveys of trends of development of industrial companies is being
given. I have invoked data of the Department of statistics. Questionnaire has been concluded and sent to
industrial companies.
In the third part model of increase of manufacturing efficiency is chartered. Also model of installment
stages is drawn and divided. In each stage installment steps are named together with which the tool appropriate
for installment of this is offered. Advantage of the model is such that all steps are shown in priorities together
with the offered tools. For i have been in lack of this after analyzing suggested by other authors, I have a mind
that my model would be very helpful for the beginning companies for the installment of Lean.
The final work is consisted of four parts:... [to full text]Baigiamajame magistro darbe nagrinėju pramonės įmonių gamybos efektyvumo kelimą. Labiausiai koncentruojos ties gamybos efektyvumo kelimo modelio sukūrimu. Kuris labiausiai tiks pramonės įmonėms, kuriuos specializuojasi metalo apdirbimo ir suvirinimu. Pirmoje dalyje atlikta mokslinės - metodinės literatūros analizę gamybos kelimo efektyvumo tema aprašiau pagrindines sąvokas. Išnagrinėjau įvairius gamybos organizavimo aspektus. Įsigilinau į gamybos valdymo principus bei išanalizavau Lean įrankių pasirinkimo principus atsižvelgdamas į įmonėse nusistatytus kriterijus. Antroje dalyje yra pateikiama pramonės įmonių plėtros tendencijų tyrimus. Pasitelkiau Statistikos departamento teikiamus duomenys. Buvo sudaryta klausimų anketa ir išsiustos į pramonės įmones. Trečioje dalyje aprašytas mano sukurtas gamybos efektyvumo kelimo modelis. Taip pat nubražytas ir suskirstytas į modelis į diegimo etapus. Kiekviename etape yra įvardijami diegimo žingsniai, šalia kurių yra pasiūlytas tam žingsniui idiegti, galimas įrankis. Modelio privalumas tame, kad visi žingsniai yra parodyti eiles tvarka ir šalia pasiūlyti įrankiai. Kadangi išnagrinėjes kitų autorių pasiūlytus to pasigedau, manau kad mano modelis labai padėtų pradedančioms įmonėms įsidiegti Lean. Baigiamaji darba sudaro keturios dalis: įvadas, mokslinės literatūros analizė, empiriniai tyrimai ir sukurto modelio aprašymas kartu su įgyvendinimu. Taip pat patektos išvados bei pasiūlymai, literatūros sąrašas ir priedai. Darbo apimtis - 92p... [toliau žr. visą tekstą]
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Figueredo, Stacy L. (Stacy Lee) 1981. "Parabolic trough solar collectors : design for increasing efficiency." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/68524.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 193-200).
Parabolic trough collectors are a low cost implementation of concentrated solar power technology that focuses incident sunlight onto a tube filled with a heat transfer fluid. The efficiency and cost of the parabolic trough collector designs is influenced by structural stiffness, choice of materials, assembly tolerances, mirror cleanliness and wear. Current performance estimates of solar trough optical field efficiencies are 54.2% [1]. The goal of this research is to identify general methods and specific design concepts for achieving increased collector efficiency. This thesis has investigated improvements in the design of a parabolic trough module by looking first at the overall structural concept of the collector to reduce complexity while maintaining structural stability under wind loading conditions. In the process of evaluating the feasibility of one such concept, a monolithic reflector panel with a mirror film front surface, details related to the mirror surface efficiency were investigated. At the panel-structure to mirror interface, surface roughness of the underlying structural backing was studied to understand performance effects on the mirror film surface that would make one backing material potentially more suitable than another would. In this case it was found that three materials tested: gel-coated fiberglass, rolled aluminum, and rolled steel were all similarly effective when compared to a more expensive mirrored aluminum backing material. When looking at the integration of the larger structural changes with the factors that affect surface reflectivity of parabolic mirrors, it became apparent that contamination of the surfaces and cleaning were major factors in reduced module effectiveness. Given that the conceptual development of the structure is ongoing, research into contamination factors and potential cleaning solutions were considered in such a way that panel cleaning solutions could be integrated into the trough module design from the start. A vortex generator cleaning concept, which uses V-shaped extruded forms to create vortices over a mirror panel in the presence of flow over the surface, was tested as a passive cleaning solution.
by Stacy L. Figueredo.
Ph.D.
9
Wicker, Kai. "Increasing resolution and light efficiency in fluorescence microscopy." Thesis, King's College London (University of London), 2010. https://kclpure.kcl.ac.uk/portal/en/theses/increasing-resolution-and-light-eciency-in-uorescence-microscopy(810135dc-d08b-4084-b4a1-9f7e572146d6).html.
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Structured illumination microscopy (SIM) can be used to enhance the lateral resolu-tion and the sectioning capability in microscopic imaging. As a wide-field technique it may have advantages over scanning approaches such as stimulated emission depletion (STED) microscopy regarding acquisition time and bleaching. Similar to the genera-tion of moire ́ patterns, the structured illumination transposes high spatial frequency information in the sample into low spatial frequency information, which can then be recorded by the microscope and computationally recovered in order to generate high resolution images. However, numerous experimental factors can lead to the generation of artefacts in the final image. Therefore, sophisticated algorithms are needed for the reconstruction of high quality images from raw data. This thesis discusses the experi-mental challenges of structured illumination microscopy and newly developed methods of addressing these in the reconstruction process. The final images show good quality and a resolution improvement of about a factor of two. Confocal microscopy is another technique used for achieving optical sectioning of biological specimen. By using a pinhole in the detection pathway out-of-focus light is blocked, leading to the desired sectioning effect. Closing the pinhole further also allows an enhancement of the lateral resolution; however this comes at the cost of strongly reduced light efficiency, as less light passes through the pinhole. Adding an interferom-eter with relative image inversion optics between its two arms to the descanned output of a confocal microscope makes it possible to surpass the lateral resolution limit (closed pinhole) of confocal microscopes for large pinholes, significantly increasing the light efficiency of such a microscope. This thesis presents the theoretical description of this method as well as experimental results confirming it.
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Haidorfer, Luke. "Efficiency alone as a solution to increasing energy consumption." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32894.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (leaves 31-33).
A statistical analysis was performed to determine the effect of efficiency on the total US energy consumption of automobiles and refrigerators. Review of literature shows that there are many different opinions regarding this issue. Trends in energy consumption were constructed using historical data from government agencies and prior studies on energy efficiency. The discussion includes a range of topics that help to understand what factors influence changes in energy consumption the most. It was found that increasing efficiency was not able to reduce motor fuel consumption for automobiles, but was successful in decreasing electricity consumption for refrigerators.
by Luke Haidorfer.
S.B.
11
Fougner, Alexander. "Increasing energy efficiency and instruction scheduling by software prefetching." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-292714.
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With the increasing problems related to semiconductor process node shrinkage and the expansion of the mobile devices market, the requirements for energy efficiency are continuously constrained. Alternative methods such as Decoupled Access/Execute adapts software to better fit dynamic voltage and frequency scaling. Targeting the energy inefficient Out-of-Order execution logic new methods propose to increase energy efficiency by moving the Out-of-Order logic from hardware level to software level by enabling reordering of loop iterations. One way to enable reordering of iterations is to transform a loop to backwards recursion. The aim of this thesis is to investigate transformations of loops into recursions and to evaluate the resulting performance impact. This thesis presents a source language independent implementation of a LLVM compiler pass transforming loops into forward and backward recursions. The performance impact is evaluated by choosing parallel loops from the Rodinia benchmark, measuring the recursion overhead for different recursion depths. In certain cases, tight loops showed a variation in overhead ranging between 22% to 78% for the backwards recursion case depending on recursion depth, whereas for loose loops the observed overhead for some loops were as low as 1% regardless of the recursion depth.
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Newby, Adam F. "Increasing Water Application Efficiency in Greenhouse Crop Production UsingGravimetric Data." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366376123.
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Wang, Kai. "Review on increasing efficiency of biogas production from sewage sludge." Thesis, KTH, VA-teknik, Vatten, Avlopp och Avfall, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99357.
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Sewage sludge is widely used as an important source for biogas production through digestion. Developing the high performance processes has a significant goal in order to promote energy efficiency and reduce the cost sewage sludge treatment. The problem of sewage sludge disposal is becoming top one which almost cost 50 % of running fee for a municipal wastewater treatment plant. This paper basically introduces three methods to improve the conventional digestion. However, they enhance the conventional digestion from different aspects. For examples, Two-phase anaerobic digestion enables to exhibit the merit of thermophilic anaerobic digestion and avoid the weak points of conventional digestion regarding odor problem. In two-phase anaerobic digestion, the acid and methane producing stages are separated. Extended solids retention time is an approach to separate the hydraulic retention time and solids retention time in an anaerobic digester by using recycle thickening. This method could benefit further de-composing the organics and increase methane formation. Dewaterability is the final step of anaerobic digestion process. Enhancing this part of process is an efficient way to increase the solid content of sludge that would reduce the transportation costs. In a nutshell, no matter on saving cost or energy perspectives, these three methods all promote biogas production efficiency up to a better performance, but various requirement of energy and cost are demanded. The paper displays and compares the advantages and disadvantages among three methods. There is no certain answer to which method is the best one; however, they can be chose to enhance digestion in different condition.
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Guo, Zhigang. "Novel methods for increasing efficiency of quantitative trait locus mapping." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/374.
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Petterson, Frank William Losasso. "Algorithms for increasing the efficiency and fidelity of fluid simulations /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Linck, Marcelo Melo. "Increasing memory access efficiency through a two-level memory controller." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2018. http://tede2.pucrs.br/tede2/handle/tede/7941.
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Acessos simult?neos gerados por m?ltiplos clientes para um ?nico dispositivo de mem?ria em um Sistema-em-Chip (SoC) imp?e desafios que requerem aten??o extra devido ao gargalo gerado na performance. Considerando estes clientes como processadores, este problema torna-se mais evidente, pois a taxa de crescimento de velocidade para processadores excede a de dispositivos de mem?ria, criando uma lacuna de desempenho. Neste cen?rio, estrat?gias de controle de mem?ria s?o necess?rias para aumentar o desempenho do sistema. Estudos provam que a comunica??o com a mem?ria ? a maior causa de atrasos durante a execu??o de programas em processadores. Portanto, a maior contribui??o deste trabalho ? a implementa??o de uma arquitetura de controlador de mem?ria composta por dois n?veis: prioridade e mem?ria. O n?vel de prioridade ? respons?vel por interagir com os clientes e escalonar requisi??es de mem?ria de acordo com um algoritmo de prioridade fixa. O n?vel de mem?ria ? respons?vel por reordenar as requisi??es e garantir o isolamento de acesso ? mem?ria para clientes de alta prioridade. O principal objetivo deste trabalho ? apresentar um modelo que reduza as lat?ncias de acesso ? mem?ria para clientes de alta prioridade em um sistema altamente escal?vel. Os experimentos neste trabalho foram realizados atrav?s de uma simula??o comportamental da estrutura proposta utilizando um programa de simula??o. A an?lise dos resultados ? dividida em quatro partes: an?lise de lat?ncia, an?lise de row-hit, an?lise de tempo de execu??o e an?lise de escalabilidade.
Simultaneous accesses generated by memory clients in a System-on-Chip (SoC) to a single memory device impose challenges that require extra attention due to the performance bottleneck created. When considering these clients as processors, this issue becomes more evident, because the growth rate in speed for processors exceeds the same rate for memory devices, creating a performance gap. In this scenario, memory-controlling strategies are necessary to improve system performances. Studies have proven that the main cause of processor execution lagging is the memory communication. Therefore, the main contribution of this work is the implementation of a memory-controlling architecture composed of two levels: priority and memory. The priority level is responsible for interfacing with clients and scheduling memory requests according to a fixed-priority algorithm. The memory level is responsible for reordering requests and guaranteeing memory access isolation to high-priority clients. The main objective of this work is to provide latency reductions to high-priority clients in a scalable system. Experiments in this work have been conducted considering the behavioral simulation of the proposed architecture through a software simulator. The evaluation of the proposed work is divided into four parts: latency evaluation, row-hit evaluation, runtime evaluation and scalability evaluation.
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Linck, Marcelo Melo. "Increasing memory access efficiency through a two-level memory controller." Pontifícia Universidade Católica do Rio Grande do Sul, 2017. http://hdl.handle.net/10923/11744.
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Previous issue date: 2017Simultaneous accesses generated by memory clients in a System-on-Chip (SoC) to a single memory device impose challenges that require extra attention due to the performance bottleneck created. When considering these clients as processors, this issue becomes more evident, because the growth rate in speed for processors exceeds the same rate for memory devices, creating a performance gap. In this scenario, memory-controlling strategies are necessary to improve system performances. Studies have proven that the main cause of processor execution lagging is the memory communication. Therefore, the main contribution of this work is the implementation of a memory-controlling architecture composed of two levels: priority and memory. The priority level is responsible for interfacing with clients and scheduling memory requests according to a fixed-priority algorithm. The memory level is responsible for reordering requests and guaranteeing memory access isolation to high-priority clients. The main objective of this work is to provide latency reductions to high-priority clients in a scalable system. Experiments in this work have been conducted considering the behavioral simulation of the proposed architecture through a software simulator. The evaluation of the proposed work is divided into four parts: latency evaluation, row-hit evaluation, runtime evaluation and scalability evaluation.
Acessos simultâneos gerados por múltiplos clientes para um único dispositivo de memória em um Sistema-em-Chip (SoC) impõe desafios que requerem atenção extra devido ao gargalo gerado na performance. Considerando estes clientes como processadores, este problema torna-se mais evidente, pois a taxa de crescimento de velocidade para processadores excede a de dispositivos de memória, criando uma lacuna de desempenho. Neste cenário, estratégias de controle de memória são necessárias para aumentar o desempenho do sistema. Estudos provam que a comunicação com a memória é a maior causa de atrasos durante a execução de programas em processadores. Portanto, a maior contribuição deste trabalho é a implementação de uma arquitetura de controlador de memória composta por dois níveis: prioridade e memória. O nível de prioridade é responsável por interagir com os clientes e escalonar requisições de memória de acordo com um algoritmo de prioridade fixa. O nível de memória é responsável por reordenar as requisições e garantir o isolamento de acesso à memória para clientes de alta prioridade. O principal objetivo deste trabalho é apresentar um modelo que reduza as latências de acesso à memória para clientes de alta prioridade em um sistema altamente escalável. Os experimentos neste trabalho foram realizados através de uma simulação comportamental da estrutura proposta utilizando um programa de simulação. A análise dos resultados é dividida em quatro partes: análise de latência, análise de row-hit, análise de tempo de execução e análise de escalabilidade.
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Alves, Marco Antonio Zanata. "Increasing energy efficiency of processor caches via line usage predictors." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/96062.
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O consumo de energia se torna cada vez mais importante para a arquitetura de processadores, onde o número de cores dentro de um mesmo chip está aumentando mas o total de energia disponível se mantém no mesmo nível ou até mesmo se reduz. Assim, técnicas para economizar energia, tais como opções de escala de frequência e desligamento automático de subsistemas, estão sendo usadas para manter a troca entre energia e desempenho. Para se obter alto desempenho, os atuais Chip Multiprocessors (CMPs) integram grandes memórias cache a fim de reduzir a latência média para acesso a memória principal, através da alocação do conjunto de dados da aplicação dentro do chip. Essas memórias cache tem sido projetadas tradicionalmente para explorar a localidade temporal usando políticas de substituição inteligentes e localidade espacial buscando todos os dados da linha da cache após uma falta de dados. Entretanto, estudos recentes mostraram que o número de sub-blocos dentro da linha da memória cache, que são realmente usados, costuma ser baixo, sendo que, os sub-blocos que são usados recebem poucos acessos antes de se tornarem mortos (isto é, nunca mais são acessados). Além disso, muitas da linhas da memória cache permanecem ligadas por longos períodos de tempo, mesmo que os dados não sejam usados novamente ou são inválidos. Para linhas de cache modificadas, a memória cache aguarda até que a linha seja expulsa para que esta seja gravada (write-back) de volta no próximo nível de memória. Essas escritas competem com as requisições de leitura (demanda do processador e prébusca da cache), aumentando a pressão no controlador de memória. Por essas razões, a eficiência energética e o desempenho das memórias cache não são ideais. Essa tese propõe a aplicação de preditores de uso de linhas da cache para aumentar a eficiência energética das memórias cache. São propostos os mecanismos Dead Sub-Block Predictor (DSBP) e Dead Line and Early Write-Back Predictor (DEWP) para permitir economia de energia sem que haja degradação do desempenho. DSBP é usado para prever quais sub-blocos da linha da cache serão usados e quantas vezes eles serão acessados de forma a trazer para a cache apenas os sub-blocos úteis e desliga-los após eles serem acessados pelo número de vezes previsto. DEWP prevê linhas de cache mortas assim que elas recebem o último acesso, desligando essas linhas. As linhas sujas são escalonadas para sofrerem write-back após a última operação de escrita, aumentando o potencial de salvar energia, reduzindo também a pressão no controlador de memória. Ambos os mecanismos propostos também reduzem a poluição nas memórias cache, dando prioridade para a expulsão de linhas mortas, melhorando as atuais políticas de substituição. Embora cada mecanismo apresentado seja capaz de funcionar separadamente dentro do sistema, ambos os mecanismos podem também ser misturados em uma mesma hierarquia de cache. Essa implementação mista é interessante pois a granularidade de sub-bloco é preferível para níveis de cache próximos do processador, onde as linhas de memória cache são expulsas rapidamente, enquanto o último nível de cache tende a usar toda a linha antes da sua expulsão. Com o intuito de avaliar os mecanismos propostos, é apresentado o Simulator of Non- Uniform Cache Architectures (SiNUCA). Esse simulador de microarquitetura com precisão de ciclos é validado em termos de desempenho e consumo de energia através da comparação com um processador real. Os resultados de desempenho foram obtidos executando aplicações das cargas de trabalho single-threaded do conjunto SPEC-CPU2006 e aplicações multi-threaded dos conjuntos SPEC-OMP2001 e NAS-NPB. Os resultados relativos a energia foram obtidos integrando o SiNUCA com as ferramentas de modelagem Multi-core Power, Area, and Timing (McPAT) e CACTI. Quando aplicados os mecanismos em todos os níveis de memória cache, observou-se em média uma redução de 36% no consumo de energia usando o DSBP, 25% usando o DEWP e 37% quando usou-se o DSBP nos níveis L1 e L2 e o DEWP no último nível. Todas essas reduções causaram uma perda desprezível de desempenho de menos de 4% em média.Energy consumption is becoming more important for processor architectures, where the number of cores inside the chip is increasing and the total power budget is kept at the same level or even reduced. Thus, energy saving techniques such as frequency scaling options and automatic shutdown of sub-systems are being used to maintain the trade-off between power and performance. To deliver high performance, current Chip Multiprocessors (CMPs) integrate large caches in order to reduce the average memory access latency by allocating the applications’ working set on-chip. These cache memories have traditionally been designed to exploit temporal locality by using smart replacement policies, and spatial locality by fetching entire cache lines from memory on a cache miss. However, recent studies have shown that the number of sub-blocks within a line that are actually used is often low, and those sub-blocks that are used are accessed only a few times before becoming dead (that is, never accessed again). Additionally, many of the cache lines remain powered for a long period of time even if the data is not used again, or is invalid. For modified cache lines, the cache memory waits until the line is evicted to perform the write-back to next memory level. These write-backs compete with read requests (processor demand and cache prefetch), increasing the pressure on the memory controller. For these reasons, the energy efficiency and performance of cache memories are not ideal. This thesis introduces cache line usage predictors to increase the energy efficiency of cache memories. We propose the Dead Sub-Block Predictor (DSBP) and Dead Line and Early Write-Back Predictor (DEWP) mechanisms to enable energy savings without performance degradation. DSBP is used to predict which sub-blocks of a cache line will be actually accessed and how many times they will be used in order to bring into the cache only those sub-blocks that are necessary, and power them off after they are accessed the predicted number of times. DEWP predicts dead lines as soon as they receive the last access, and turns off these lines. Dirty lines are scheduled for write-back after the last write operation occurs, increasing the energy savings potential and also reducing the pressure on the memory controller. Both proposed mechanisms also reduce pollution in cache memories by prioritizing dead lines for eviction in the existing replacement policy. Although each introduced mechanism is capable of performing separately inside a system, both mechanisms can also be mixed in the same cache hierarchy. This mixed implementation is interesting because the sub-block granularity is more suitable for cache levels closer to the processor, where the cache lines are quickly evicted, while the Last- Level Cache (LLC) tends to use the whole cache line before its eviction. In order to evaluate our proposed mechanisms, we introduce the Simulator of Non- Uniform Cache Architectures (SiNUCA). This cycle-accurate microarchitecture simulator is validated in terms of performance and energy consumption by comparing it to a real processor. Our performance results were obtained executing single-threaded applications from SPEC-CPU2006 and multi-threaded applications from SPEC-OMP2001 and NASNPB benchmark suites. The energy related results were obtained by integrating SiNUCA with the Multi-core Power, Area, and Timing (McPAT) framework and the CACTI power modeling tool. When applying our mechanisms on all the cache levels, we observe on average a 36% energy reduction for DSBP, 25% energy reduction using DEWP and an average reduction of 37% in the energy consumption applying DSBP on L1 and L2 and DEWP on the LLC. All these reductions caused a negligible performance loss of less than 4% on average.
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Singh, Rajput Shivaram. "Increasing efficiency in ECU function development for Battery Management Systems." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-206088.
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In the context of automotive industries today, the focus of ECU function development is always on finding the best possible combinations of control algorithms and parameter. The complex algorithms with broad implementation range requires optimal calibration of ECU parameters to achieve the desired behaviour during the drive cycle of the vehicle. With the growing function complexity of automotive E/E Systems, the traditional approaches of designing the automotive embedded systems are not suitable. In order to overcome the challenge of complexity, many of the leading automotive companies have formed a partnership in order to develop and establish an open industry standard for automotive E/E architecture called AUTOSAR. In this thesis, toolchain for ECU function development following AUTOSAR standard and an efficient measurement and calibration mechanism using XCP on CAN will be investigated and implemented. Two toolchains will be proposed in this thesis, describing their usage in different stages of ECU function development and in calibration. Both these toolchains will be tested to prove its working.I området utveckling av funktionalitet på elektroniska styrsystem inom bilindustrin idag, ligger fokus på att finna den bästa kombinationen av reglermetoder och styrparametrar. Dessa avancerade system, med breda användningsområden, kräver bästa möjliga injustering av dess kalibrerbara parametrar, för att nå önskat beteende vid användning av fordonet. Det ökande omfånget av funktionskraven på styrsystemen, innebär att sedvanlig metodik för utveckling av dessa system inte är lämplig. För att kunna lösa dessa svårigheter, har de stora inom bilindustrin ingått ett samarbete, där de tillsammans skapat och utvecklar en industristandard för funktionsoch systemutveckling av styrsystem. Standarden kallas AUTOSAR. Denna rapport beskriver hur en kedja av utvecklingsverktyg som följer AUTOSAR-standarden kan användas, för att undersöka och använda en metod för systemövervakning och parameterkalibrering, genom användning av XCP över CAN.
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Gurbag, Ali, and Valuis Guadalupe Katherine Morales. "Increasing the efficiency of marketing e-mail in customer retention." Thesis, Högskolan i Jönköping, Internationella Handelshögskolan, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-30301.
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Technology development has changes many things in the way businesses are done nowadays. Compa-nies needed to readapt their processes to the new demands of the markets in order to be competitive in online platforms. To achieve this, companies need to focus on retaining customers. E-marketing has developed many tools for this purpose, e-mail marketing has proven to have advantages in this task; however, sometimes the outcome is not as good as expected, mainly because the content and struc-ture isn’t what customers want to see or don’t fulfill their expectations.The purpose of this study is understand which are the factors that make customers avoid marketing e-mails and how they can be restructured to increase the probabilities to encourage customers to revisit again the same brand.Regarding the method, quantitative approach was used and the statistical data was collected with online survey. Survey questions are prepared based on previous literature and factors mentioned in literature. Results are collected from a sample which contains 120 people. In order to analyze the col-lected data, descriptive analysis and principal component analysis techniques are used.After analysis, researchers concluded that not all factors which influence ignoring decision have same effect. On the other hand, during decision of revisit the brand because of the marketing e-mails, each segments in the sample have different preference and companies which use marketing e-mail should structure their e-mails regarding to that data.
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Рибалка, Павло Валерійович, Павел Валерьевич Рыбалка, and Pavlo Valeriiovych Rybalka. "Increasing efficiency of machining high-precision holes with noncontinuous surfaces." Thesis, Sumy State University, 2016. http://essuir.sumdu.edu.ua/handle/123456789/46876.
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This paper is about a center hole with noncontinuous surface of a
centrifugal pump impeller. The main subject is deviation of cylindrical
shape of an impeller center hole and its concentricity to sealing surfaces.
The purpose is finding a logarithm of getting precise cylindrical shape of
the hole.
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Peiker-Feil, Eva Dorothea [Verfasser]. "Increasing the bandwidth efficiency of OFDM-MFSK / Eva Dorothea Peiker-Feil." Ulm : Universität Ulm. Fakultät für Ingenieurwissenschaften und Informatik, 2015. http://d-nb.info/1066736413/34.
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Aljoaba, Sharif. "ACTIVE OPTIMAL CONTROL STRATEGIES FOR INCREASING THE EFFICIENCY OF PHOTOVOLTAIC CELLS." UKnowledge, 2013. http://uknowledge.uky.edu/ece_etds/18.
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Energy consumption has increased drastically during the last century. Currently, the worldwide energy consumption is about 17.4 TW and is predicted to reach 25 TW by 2035. Solar energy has emerged as one of the potential renewable energy sources. Since its first physical recognition in 1887 by Adams and Day till nowadays, research in solar energy is continuously developing. This has lead to many achievements and milestones that introduced it as one of the most reliable and sustainable energy sources. Recently, the International Energy Agency declared that solar energy is predicted to be one of the major electricity production energy sources by 2035.
Enhancing the efficiency and lifecycle of photovoltaic (PV) modules leads to significant cost reduction. Reducing the temperature of the PV module improves its efficiency and enhances its lifecycle. To better understand the PV module performance, it is important to study the interaction between the output power and the temperature. A model that is capable of predicting the PV module temperature and its effects on the output power considering the individual contribution of the solar spectrum wavelengths significantly advances the PV module designs toward higher efficiency.
In this work, a thermoelectrical model is developed to predict the effects of the solar spectrum wavelengths on the PV module performance. The model is characterized and validated under real meteorological conditions where experimental temperature and output power of the PV module measurements are shown to agree with the predicted results.
The model is used to validate the concept of active optical filtering. Since this model is wavelength-based, it is used to design an active optical filter for PV applications. Applying this filter to the PV module is expected to increase the output power of the module by filtering the spectrum wavelengths. The active filter performance is optimized, where different cutoff wavelengths are used to maximize the module output power. It is predicted that if the optimized active optical filter is applied to the PV module, the module efficiency is predicted to increase by about 1%. Different technologies are considered for physical implementation of the active optical filter.
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Stallard, Nigel. "Increasing efficiency in the design and analysis of animal toxicity studies." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282731.
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Espindle, L. P. (Leo P. ). "Process management principles for increasing the energy efficiency of manufacturing operations." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66070.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; in conjunction with the Leaders for Manufacturing Program at MIT, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 81-84).
Energy usage is a significant operating cost for manufacturing facilities in the United States, and interest in energy management has been rising of late, 2, 3]. One approach, recommended by the Environmental Protection Agency (EPA), is to piggyback off of an existing lean program to reduce energy waste in manufacturing processes(4]. Just such a pilot program has recently been launched in a major manufacturing facility at Raytheon, where approximately 48% of the facilities' total energy is used on manufacturing processes. The program focuses on proven process management approaches and rides the coattails of the existing lean program at a major manufacturing facility by creating a pull for continuous improvement ideas[1]. The goal this thesis was to increase the efficacy of the existing program, and to develop a practical roadmap to guide energy managers seeking to execute such programs in manufacturing on the shop floor. We investigated three methods to enhance the program. One was to apply the Design, Measure, Analyze, Improve, Control (DMAIC) method, made popular in Six Sigma literature, to the energy waste reduction efforts of a manufacturing area. By shifting focus to more energy intensive equipment, the area quadrupled the amount of energy savings per improvement, and is in line to achieve a 10% reduction in electricity usage(5, 4]. The second method was to provide real-time feedback on electricity usage of energy intensive equipment to workers in a manufacturing cell. During an experimental period, we found that feedback ultimately engaged area operations managers who instituted an auditing program that reduced waste by 43% (or a 26% total reduction in usage) over a short period of time[6, 7, 8, 9]. The third method was to right-size equipment based on customer demand. An analysis of this approach based on field experience revealed that major savings (50% or more reduction in electricity usage) on targeted systems can be expected as companies remove "monument" equipment in supporting smaller and more responsive process flows such as true cellular manufacturing[3, 4]. In summary, we found that application of continuous improvement principles can positively impact energy efficiency programs at manufacturing facilities. In addition the three methods are different in cost and longevity, with the DMAIC and feedback at low cost and immediate impact (but potentially fading effectiveness), and right-sizing at higher cost, but producing longer term and potentially more durable savings.
by Leo P. Espindle.
S.M.
M.B.A.
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Fuchs, Cornelius. "Increasing the light extraction efficiency of monochrome organic light-emitting diodes." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-186848.
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Organische, lichtemittierende Dioden (OLEDs) bezeichnen neuartige Lichtquellen, welche zur Beleuchtung oder für Displayanwendungen nutzbar sind. Im Allgemeinen ist die Lichtausbeute durch den hohen Brechungsindex und die Dünnschichtgeometrie der OLED begrenzt. Der hohe Brechungsindex sorgt dafür, dass ein signifikanter Anteil des emittierten Lichts in der OLED durch Totalreflexion (TIR) gefangen ist. Durch den Dünnschichtaufbau der OLED wird außerdem die Lichterzeugung für resonante Moden der kohärenten optischen Mikrokavität erhöht. Dies gilt im Besonderen für die nichtstrahlenden Moden. In dieser Arbeit wurden zwei Methoden untersucht, um die Lichtausbeute aus OLEDs zu erhöhen. Zuerst wurde die Implementierung von Materialien mit niedrigem Brechungsindex angrenzend zum undurchsichtigen metallischen Rückkontakt untersucht. Die Modifizierung des Brechungindexes verändert die Dispersionsrelation der an der Grenzfläche zwischen Metall und Dielektrikum angeregten nicht-strahlenden Oberflächenplasmonpolariton-Resonanz (SPP). Dadurch wird der Phasenraum verkleinert, in welchen effizient Strahlung abgegeben werden kann. Da die SPP-Resonanz eine nichtstrahlende Verlustquelle der Mikrokavität darstellt, wird so die Auskopplungseffizienz der OLED erhöht. In experimentellen Umsetzungen konnte die externe Quanteneffizienz (EQE) sowohl für einen Emitter gesteigert werden, welcher eine isotrope Verteilung der Strahlungsquellen besitzt (Ir(ppy)3 , +19 %), als auch für eine vorzugsweise horizontale Ausrichtung (Ir(ppy)2 (acac), +18 %). Die Steigerung der EQE korrespondiert sehr gut mit der berechneten Steigerung der Auskopplungseffizienz für die jeweiligen Mikrokavitäten (+23 %, bzw. +19 %). Weitere optische Simulationen legen den Schluss nahe, dass dieser Ansatz ebenso für perfekt horizontale Ausrichtung der Quellen sowie für weiße OLEDs anwendbar ist. Als zweiter Ansatz wurde die erhöhte Lichtausbeute durch Bragg-Streuung an periodische Linienstrukturen untersucht. In dieser Arbeit wurden Methoden untersucht, bei denen die Oberflächen strukturiert wurde, auf welche die organischen Halbleiterschichten der OLEDs aufgebracht wurden. Für bottom-OLEDs (durch ein Substrat emittierende OLEDs), wurde direkt die transparente Elektrode durch ein Laserinterferenzablationsverfahren (DLIP) modifiziert. Zusätzlich wurden top-OLEDs untersucht (direkt aus der Mikrokavität Licht emittierende OLEDs), für welche alle Schichten auf eine periodisch strukturierte Photolackschicht aufgedampft wurden. Für die bottom-OLEDs konnte für eine Gitterkonstante von 0.71 μm eine Steigerung der EQE um 27 %, verglichen zu einer optimierten unstrukturierten Referenz, ermittelt werden. Eine Vergrößerung der Gitterkonstante führt zu einer Abnahme der EQE. Die erhöhte EQE wird auf die Überlagerung des planaren Emissionsspektrums mit Beiträgen von Bragg-gestreuten, ursprünglich nicht-strahlenden Moden zurückgeführt, wobei die Intensitäten der Anteile von der Gitterkonstante und der Strukturhöhe abhängen. Für die top-OLEDs konnte eine Steigerung der EQE um 13 % für eine Gitterkonstante von 1.0 μm festgestellt werden. Im Gegensatz zu den bottom-OLEDs wird für kleinere Gitterkonstanten (0.6 μm) hier die EQE nicht erhöht. Vielmehr kommt es durch die starke Veränderung des Emissionsspektrums zu einer Erhöhung der photometrischen Lichtausbeute um 13.5 %. Die starke Veränderung des Emissionspektrums wird auf eine kohärente Kopplung zwischen den Bragg-gestreuten Moden zurückgeführt, bedingt durch die starke optische Mikrokavität dieses OLED-Typs. Um diese Effekte quantitativ zu beschreiben, wurde ein entsprechendes Modell entwickelt und implementiert. Die Qualität der Simulationsergebnisse wird anhand von Literaturreferenzen überprüft, wobei eine gute Übereinstimmung zu experimentell gemessenen Spektren erzeugt wird. Mit dem Simulationsmodell werden Vorhersagen über das Emissionspektrum und die resultierenden Effizienzen möglich. Für bottom-OLEDs wurde festgestellt, dass eine starke Veränderung des Emissionspektrums für Gitterkonstanten unterhalb von 0.5 μm erzeugt werden kann. Hingegen sind für top-OLEDs sehr schwache Strukturen oder große Gitterkonstanten notwendig, um eine nur schwache Veränderung des Emissionsspektrums und damit einen allgemeinen Effizienzgewinn zu erzeugen. Bezüglich der Gitterkonstante, ist diese Erkenntnis ist im Gegensatz zur üblichen Herangehensweise zur Implementierung periodischer Streuschichten in OLEDs. Mit der implementierten Simulationsmethode werden jedoch Aussagen bzgl. Emissionspektrum und Effizienz für eine breite Spanne an OLED-Strukturen vor der experimentellen Umsetzung möglichOrganic light-emitting diodes (OLEDs) are an attractive new light source for display and lighting applications. In general, the light extraction from OLEDs is limited due to the high refractive index of the active emitter material and the thin film geometry. The high refractive index causes the trapping of a significant portion of the emitted light due to total internal reflection (TIR). Due to the thin film layout, the light emission is enhanced for resonant modes of the coherent optical microcavity, in particular for light affected by TIR. In this work two approaches are investigated in detail in order to increase the light extraction efficiency of OLEDs. In a first approach, the implementation of a low refractive index material next to the opaque metallic back-reflector is discussed. This modifies the dispersion relation of the non-radiative surface plasmon polariton (SPP) mode at the metal / dielectric interface, causing a shift of the SPPs dispersion relation. Thereby, the phase space into which power can be efficiently dissipated by the emitter is reduced. For the SPP this power would have been lost to the cavity, such that in total the outcoupling efficiency is increased. In experiment, an increased external quantum efficiency (EQE) is observed for an emitter exhibiting isotropic orientation of the sources (Ir(ppy)3 ,+19 %), as well as for an emitter which shows preferential horizontal orientation (Ir(ppy)2 (acac), +18 %), compared to an optimized device which uses standard material. This corresponds very well to the enhancement of the outcoupling efficiencies of the corresponding microcavities (+23 %, resp. +19 %) reducing the refractive index of the hole transport layer by 15 %. Optical simulations indicate that the approach is generally applicable to a wide range of device architectures. These in particular include OLEDs with emitters showing a perfectly horizontal alignment of their transition dipole moments. Furthermore, the approach is suitable for white OLEDs. Bragg scattering was investigated as second option to increase the light extraction from OLEDs. The method requires a periodically structured surface. For the bottom-emitting OLEDs, this is achieved by a direct laser interference patterning (DLIP) of the transparent electrode. Additionally, top-emitting devices were fabricated onto periodically corrugated photoresist layers. Using a periodic line pattern with a lattice constant of 0.71 μm, the EQE of the bottom-emitting devices was enhanced by 27 % compared to an optimized planar reference. For the bottom-emitting layout, increasing the lattice constant leads to lower EQEs. The increased EQE is attributed to the superposition of the radiative cavity resonances by Bragg scattered intensities of trapped modes. The intensities depend on the lattice constants as well as the height of the periodic surface perturbation. For top-emitting OLEDs comprising a lattice constant of 1.0 μm the EQE was increased by 13 %. Reducing the lattice constant (0.6 μm) decreases the EQE, albeit the luminous efficacy is increased by 13.5 % due to a heavily perturbed emission spectrum. The perturbation is attributed to a coherent interaction of the Bragg scattered modes due to the strong optical microcavity for the top-emitting OLEDs. Thus, for strong perturbation specific emission patterns can be achieved, but an overall enhanced efficiency is difficult to obtain. To investigate the observed results theoretically, a detailed simulation approach is outlined. The simulation method is carefully evaluated using reference data from literature. Using the simulation approach, the emission patterns as well as the efficiencies of the devices can be estimated. The emission spectra reproduced from simulation are in good agreement with the experiment. Furthermore, for the bottom-emitting layout, a strong interaction can be found from simulations for lattice constants below 0.5 μm. For top-emitting OLEDs, the weak interaction regime seems to be more likely to result in an overall enhanced emission. This requires, in contrast to conventional opinion, very shallow perturbations or lattice constants which exceed the peak wavelength of the emission spectrum. However, with the established simulation approach a-priori propositions on the emission spectrum or particular beneficial device layouts become feasible
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Hussein, Engy Samy. "Green architecture as an approach for increasing energy efficiency in Egyptian buildings." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55882/.
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In the light of the growing global concerns about environmental problems and the importance of achieving sound management of the natural resources, this research proposal was developed. Though Egypt is now enjoying a secured energy supply for the short and medium terms, yet it is mainly dependent on fossil fuels. Building sector in 2007 was responsible for 23% of the total energy consumption in Egypt and is expected to reach 35% by 2030 and the construction sector growth rate was 15.8%. Developing an environmental assessment tool was the approach adopted by this study to address the building sector energy consumption levels in Egypt. The success of these tools in reshaping the design and practice worldwide has long been established. In the absence of an existing adequate measure to assess environmental buildings and with the concept of modern environmental design emerging in Egypt, the current study proposes the Egyptian Green Code for Buildings. The Egyptian Green Code for Buildings is an assessment tool specifically designed for the Egyptian environment. Three phases of surveys (questionnaires and interviews) were developed to create, evaluate and validate the proposed code. With the collaboration of the field specialists represented in: governmental officials, architects in practice and academics. The results reveal that this research has developed an understandable code, with categories relevant to the Egyptian environment, achievable credits and satisfactory overall classifications. The proposed code will insure a minimum level of applying green architecture principles in Egyptian buildings. It presents a unified, coherent and accurate method of assessment. It allows the designers and decision makers to identify the key points that need to be addressed to enhance the overall performance of a building and in turn make it beneficial to the environment. The application of the proposed code will result in green concepts being more in the centre of the architecture practice in Egypt and opening the possibilities to introducing new concepts and measures to achieve sustainability.
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Anticona, Lizama Leslie Sofía, and Yzquierdo Eylin Fabiana Medina. "Increasing the efficiency level of loading operation in a fuel distribution plant." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/653602.
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Este artículo tiene como objetivo solucionar el problema de ineficiencia, representado por el bajo nivel de servicio en el sistema de distribución de la planta de combustible, ya que se han presentado retrasos desde el inicio del proceso hasta el final de este. Por este motivo, se analizó todo el flujo del sistema para determinar en qué parte del proceso estaba la causa principal, lo que ayudaría a reducir considerablemente el problema. Se propuso aplicar un sistema de citas para estandarizar los tiempos de servicio, así como la implementación de un algoritmo y el uso de mecanismos eficientes para derivar la mejor solución robusta que responda a todas las incertidumbres con tiempos de ejecución reducidos.This article aims to solve the inefficiency problem, represented by the low service level, in the fuel plant distribution system, since there have been delays from the beginning of the process to the end of this. For this reason, the entire flow of the system was analyzed in order to determine where in the process the main cause was, which would help reduce this problem considerably. It was proposed to apply an appointment system to standardize service times as well as the implementation of an algorithm and the use of efficient mechanisms to derive the best robust solution that responds to all uncertainties with reduced execution times.
Trabajo de investigación
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Siviter, Jonathan Peter. "Increasing the efficiency of the Rankine cycle using a thermoelectric heat pump." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5802/.
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Thermal plants operating on the Rankine cycle are by far the most common method of global electrical power generation. The Rankine cycle, first developed in the late 19th century, continues to this day to be one of the most important practical implementations of a heat engine. Innovation and enhancement of the cycle continues and today's emphasis is directed towards reduced carbon emissions from the combustion of fossil fuel as well as improvement of the absolute efficiency. This thesis presents an increase in the Rankine cycle efficiency through reducing the waste heat rejected from the process by the use of a thermoelectric heat pump. A thermoelectric heat pump converts a flow of electrical charge carriers to a flow of thermal energy via phonon transport through a semiconductor lattice, described by the Peltier effect. The heat flux through the device can be modulated by varying the electrical voltage and current applied to the semiconductor. Unlike a conventional heat pump, however, the direction of heat transport is determined by the direction of migration of the charge carriers. The efficiency with which the device operates is determined by complex relationship amongst the differential temperature across the device, the geometry of the semiconductor pellets forming the device and the electrical current flow. Peltier effect devices are typically used in small-scale refrigerators, on high-power lasers to aid cooling and to maintain the wavelength stability of optical communications networks. In this thesis the application of a heat pump to recover a portion of the waste thermal energy normally rejected from the Rankine cycle process after the re-condensation of feedwater in the condenser of a steam turbine is considered. Firstly, a theoretical statement of the required Coefficient of Performance for economic operation of such a system is derived. This is followed by an experimental investigation to determine if the calculated performance is available using today's thermoelectric technology point. The thesis then presents a rigourous analysis of novel experimental apparatus used to characterise the impact of redirecting enthalpy normally rejected from the process to instead reducing the fuel load to the plant and concludes with an assessment of the economic benefits such a heat pump system would bring.
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Malenevska, Kira. "Humor as a key to increasing the efficiency of the work process." Thesis, Київський національний університет технологій та дизайну, 2019. https://er.knutd.edu.ua/handle/123456789/13086.
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Carnahan, Christina. "Teaching students with Autism in group settings increasing teacher efficiency and student learning /." Cincinnati, Ohio University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?ucin1179420087.
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Thesis (Dr. of Education)--University of Cincinnati, 2007.Title from electronic thesis title page (viewed July 21, 2007). Includes abstract. Keywords: autism; instructional context Includes bibliographical references.
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Johansson, Wilhelm. "Optical active thin films on cover glass increasing the efficiency of photovoltaic modules." Thesis, Linnéuniversitetet, Institutionen för byggd miljö och energiteknik (BET), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75044.
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Thin film coatings of ZnO, TiO2, CeOX and BiOX have been deposited on soda lime silica glass through spray pyrolysis. The effects on the optical properties of the coated glass, as well as the possible impacts on the life expectancy and energy efficiency of PV-modules have been studied. ZnO and TiO2 coatings both reduced the transmission of UV radiation of wavelengths destructive to PV-modules. Therefore, both have the potential to increase the life expectancy of PV-modules if used on cover glass. The ZnO thin film also showed an increase in photoluminescence at 377 nm when radiated with UV radiation of 325 nm while TiO2 reduced the photoluminescence. ZnO coatings on the cover glass have the potential to increase the efficiency of PV-modules in addition to UV protection. No CeOX or BiOX films were found to be deposited with the method used. The ZnO and TiO2 coated samples showed a decrease in transmission of light, due to increased reflection and possibly scattering. This needs to be addressed if these kinds of coatings are going to be beneficial for Si PV-modules.
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Backéus, Lina. "THE BEST WAY TO WORK : Increasing the efficiency through layout changes and standardization." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-85890.
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This is a master thesis done in the program of industrial design engineering at Luleå University ofTechnology, conducted during the spring of 2021. The project is a collaboration with Epiroc RockDrills AB which is a leading global company in the mining industries, and the workshop in which thisthesis is made manufactures and assembles rock drills sold worldwide. The aim of this thesis is toincrease the utilization of three lathes in the workshop that are often left unused when theiroperators have to leave the machines to perform other tasks. This is due to short operation timesthat require the operator to be present.The project follows a cyclic method in order to force the work forward without worrying aboutmissing information. There were three cycles with different aim. In the first cycle, the focus was onplanning the project and mapping the current state. In the second, a requirement specification wasmade and concepts were created. These concepts were further developed in the third cycle. Finally arecommendation was made.The current state was mapped using different methods like interviews and spaghetti diagram. Thesemethods showed that the lathes were unused mainly during setups, and that setups were timeconsuming due to equipment being placed far away from the lathes. The result showed that manyproblems could be related to bad layout design and lack of standardized work. In order to create abetter layout for the operators, a relationship chart was made and several suggestions constructedbased on it. The purpose of the layout changes was to get necessary equipment closer to the lathesin order for the setups to be performed faster. All suggestions were compared to the requirementspecification and only three were further developed during the third cycle.The lean tool SMED (Single Minute Exchange of Die) was used to create a standard for setups. Thisstandard was further developed into a work instruction to be better visualized for the operators.The final recommendation is to make layout changes according to one of the layouts presented inthis report, and to implement the work instruction. These changes will increase the utilization bypreparing as much as possible before the lathe is tuned off.
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CARNAHAN, CHRISTINA. "TEACHING STUDENTS WITH AUTISM IN GROUP SETTINGS: INCREASING TEACHER EFFICIENCY AND STUDENT LEARNING." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1179420087.
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Richard, Ryan. "Increasing the computational efficiency of ab initio methods with generalized many-body expansions." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1385570237.
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Lutfullaeva, Anbara. "Wet Electrostatic Precipitator, Increasing the Efficiency of Collecting Dust Particlesthrough Vibrating Precipitator Analysis." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1584444404824906.
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O'Donnelly, Kerry. "Towards increasing the efficiency of Rubisco, through the use of carbonic anhydrase mimetics." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/34317.
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Increasing photosynthetic efficiency remains one of the few routes left for substantial increases in crop yields. Rubisco, the enzyme responsible for fixating carbon dioxide from the atmosphere, is one of the major bottlenecks of photosynthesis. Some organisms have evolved carbon concentrating mechanisms, utilising carbonic anhydrase, to increase photosynthetic efficiency, by increasing local CO2 concentrations around Rubisco. This project aims to chemically mimic the role of carbonic anhydrase, through the use of small metal-ligand complexes, and to test their ability to perturb Rubisco's activity. In order to achieve this goal, Rubisco had to be first isolated, and a robust Rubisco assay developed, to screen the efficacy of the CA mimetics. A hydrophobic interaction chromatography protocol for the isolation of Rubisco was developed, which eliminated the requirement of salt removal before column chromatography, reducing the number of purification steps in comparison to existing methods. The rapid protocol was employed to obtain highly pure and highly active Rubisco from Spinacia oleracea and Brassica oleracea. Furthermore, the protocol revealed, for the first time, the presence of hydrophobically distinct populations of Rubisco. A fast and sensitive 384-well plate Rubisco enzymatic assay was also developed, providing a robust platform to screen and test the efficacy of the carbonic anhydrase mimetics on Rubisco's activity. A suite of existing and novel carbonic anhydrase mimetics were synthesised. A comparison of the pH-dependant CO2/HCO3- catalytic rates revealed a number of insights into the parameters that promote high interconversion rates of HCO3- to CO2: i) high electron-donating ligands, and hydrophobic ligands for 'substrate channelling' increased HCO3- dehydration rates, ii) higher pKa values for Zn-OH2, favoured the interconversion of HCO3- to CO2, iii) Zn(II) was shown to have the highest catalytic rate for HCO3- dehydration, which was attributed to the weaker binding of HCO3- to Zn(II) than to Cu(II), Co(II) and Ni(II). Additionally, this thesis provides the first proof of concept data for the use of chemical tools that could help towards mitigating the loss of Rubisco's inefficiencies. Zn(II) mimetics were shown to alter Rubisco's activity, which was attributed to a change in local CO2 concentrations, following the addition of the mimetics.
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Khorshidi, Nasrin, and Beyza Arikan. "Experimental Practice in order to Increasing Efficiency of Biogas Production by Treating Digestate Sludge." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18706.
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According to national and international policies in order to protect environment regarding renewable sources of energy, biogas is one of the best alternative to reduce waste and pollution and getting energy. Biogas is the gas that is produced by some kinds of microorganisms in anaerobic condition from organic waste treatment. Technology of biogas plants is varies and there is no standard procedure that is applicable worldwide. Methane (biogas), which is produced from wastes and it is known widely since 1973. By organic waste degradation methane is produced and waste volume will be reduced. Some surveys prove that during anaerobic digestion only 50% of organic matter is degraded. Anaerobic degradation has some steps that are hydrolysis, acidogenesis, acetogenesis and methanogenesis. Since hydrolysis is rate-limited step it can be improved by some pretreatment and some action like improving monitoring system can show that the efficiency of biogas will increase. There are three main pretreatment methods. During this study digestate sludge from different waste treatment plants were pretreated. First experience was pretreating digestate sludge from Sobacken, Falköping, Västerås by Enzyme Addition (Cellolase) and the measuring of biogas (methane) has done by Gas Chromatograph (GC). Second experience was pretreating digestate sludge by Acid (Sulfuric acid). The data of those measurements are shown that the amount of biogas was increased two times in the case of Västerås by enzyme addition, which is about 70% of theoretical expectation of this pretreatment and pretreating digestate sludge of Sobacken by acid pretreatment could increase the amount of biogas two times as well that was about 60% of theoretical estimation. By proper gas chromatograph and choosing one kind of waste and pretreating that by just one kind of pretreatment in each experience and following the results and going further the biogas efficiency will increase significantly because still 50% organic matter is inside the digester.Uppsatsnivå: D
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Fritz, Ronda. "Increasing Observations and Feedback Efficiency to Improve Instructional Quality in Small Group Intervention Settings." Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20698.
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The current study investigated the reliability and validity of using short observations with an observation tool designed to measure implementation of small group interventions. Intervention lessons for eight instructional groups from two schools were video recorded for nine weeks, and post-test assessments of reading decoding were administered to 31 at-risk kindergarten students. Videos of intervention instruction from weeks two, five, and eight, each representing a phase in the intervention period, were used within this study for measuring implementation. Each video was divided into three ten-minute segments representing the beginning, middle, and end of each intervention lesson. Video segments were coded for implementation using the Quality of Intervention Delivery and Receipt tool (QIDR; Harn, Forbes-Spear, Fritz, & Berg, 2012). Overall, the results of this study indicate that a) reliability can be achieved when using 10-minute observations, b) QIDR scores obtained from 10-minute segments are strongly correlated with scores obtained from full-length observations, c) there is no statistical difference in scores obtained from full-length observations and those obtained in 10-minute segments, and d) QIDR scores obtained from both full-length and 10-minute segments accounted for group differences in student outcomes, with lesson segments obtained from the end of lessons accounting for the most variance. Implications for research and practice are discussed, including the importance of thorough training and calibration to maintain reliability, as well as the feasibility and utility of providing frequent observation and feedback through shorter observations.
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Kennedy, Shane. "Identifying constraints to increasing yield potential of spring barley." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/16177.
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The literature suggests that grain number largely determines and as such limits yield in barley. Many of the reported studies were conducted in relatively low yielding environments and it is unclear if grain number is also a limiting factor in high yield potential climates. Nor is it known with certainty what physiological or morphological traits must be targeted in order to increase grain number. There may be a degree of trade-off between yield components whereby grain number is adjusted according to resource availability to the plant, either pre- or post-anthesis, in a way that ensures consistently well-filled grains at harvest. If mechanisms exist for adjusting grain numbers or grain storage capacity after anthesis to match assimilate availability, this may place limits on how far yield can be increased without increasing post-anthesis assimilate production. In order to determine the scope for increasing the yield potential of barley a more thorough understanding of the potential trade-offs between grain number, grain storage capacity and post-anthesis assimilate supply is required. The aim of research reported in this thesis was to establish what determines the yield of spring barley in Ireland and to investigate the timing and possible mechanisms involved in regulating grain number and grain storage capacity in relation to the supply of photoassimilates. Field experiments were carried out on spring barley (Hordeum vulgare L., cv. Quench) at several locations in Ireland from 2011 to 2013. A sub-set of experiments involving destructive sampling and in-field assessments on plots managed as per current best farm practice gathered crop growth, development, and yield component data across sites and seasons in order to establish what determines yield under typical crop production conditions. Separate experiments artificially manipulated the source:sink ratio of plots via shading and seed rate treatments to investigate in more detail the mechanisms determining grain number and grain weight and any potential trade-off between the two components. Grain number accounted for most of the variation in yield across 9 site/seasons of crops managed as per current best practice in Ireland (P < 0.001; R2 = 0.84) while grain weight remained relatively conserved. Ear number accounted for most of the variation in grain number (P = 0.002; R2 = 0.75) and ear number itself was largely determined by shoot survival from an early season peak through to harvest (P <0.001; R = 0.96). Shoot size and weight at the beginning of stem extension had the largest influence on shoot survival. Shading treatments were used to test whether there was a mechanism for adjusting grain numbers after anthesis to match the availability of assimilate for grain filling. Substantial post-anthesis reductions in assimilate supply during grain filling in 2011 and 2012 did not significantly reduce grain number (P > 0.05). A small reduction in grain number (8%) was found in response to shading for a two week period early post-anthesis in 2013, however this was likely a reduction in grain set in shoots or spikelets that reached anthesis after the treatment was imposed rather than a post-anthesis abortion or down-regulation of grain number. Percentage light interception by well managed (unshaded) canopies shortly after anthesis was generally greater than 93% across several sites and seasons, therefore increasing grain numbers to increase sink capacity would likely be associated with an unavoidable decrease in the amount of light intercepted per grain during the early grain development period. However, experiments showed that grain weight at harvest was neither reduced nor increased in response to variations in light interception during this period of endosperm development (P > 0.05), because soluble sugar concentrations in the grain were maintained at the expense of storage reserve deposition in the stems. Results suggest that grain number and grain storage capacity may both be determined pre-anthesis resulting in a trade-off during stem extension whereby grain numbers are adjusted in a way that helps conserve grain weight. A strong negative relationship between ear number and grain number per ear (P < 0.001; R2 = 0.81) across two sites of seed rate experiments in 2013 resulted in a plateau in overall grain number of approximately 18,000 grains m-2 suggesting that there may be a limit to how many grains can be established in a given environment; this was achieved with an ear number of approximately 1000 ears m-2. Yield potential for Irish conditions was estimated at 12.29 t ha-1 at 85% dry matter based on estimates of potential assimilate supply during grain filling; with a grain number of 26,481 m-2 required to utilise this. These estimates are both 44% higher than the mean yield and grain number achieved in crops managed as per current best farm practice. Once high potential ear numbers are secured (> 1000 m-2), breaking the negative relationship between ear number and grain number per ear may hold the key to further increasing grain number and hence yield potential. Increasing assimilate production and partitioning to ears during stem extension, either through increases in the duration of stem extension or solar radiation use efficiency, may enable larger grain numbers to be produced whilst maintaining or increasing individual grain storage capacity and deposition of stem storage reserves. Water and nutrient availability, as well as susceptibility to lodging may present further limitations to yield in the future.
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Kassem, Riad. "Reproduction in the Awassi ewe particular reference to increasing efficiency under semi-arid conditions." Thesis, Bangor University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328270.
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McDermott, James W. "Improving and increasing the efficiency of the P-8A Test Work Description (TWD) process." Thesis, Monterey, California : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Sep/09Sep%5FMcDermott.pdf.
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Thesis (M.S. in Systems Engineering Management)--Naval Postgraduate School, September 2009.Thesis Advisor(s): Rhoades, Mark M. "September 2009." Description based on title screen as viewed on November 5, 2009. Author(s) subject terms: Aircraft Test, Test Working Description, Process Modeling. Includes bibliographical references (p. 65-66). Also available in print.
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Ruiz, Nathan Daniel. "Increasing Isentropic Efficiency with Hydrostatic Head and Venturi Ejection in a Rankine Power Cycle." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1450.
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This thesis describes the modifications made to the Cal Poly Thermal Science Laboratory’s steam turbine experiment. While the use of superheating or reheating is commonly used to increase efficiency in a Rankine cycle the methods prove unfeasible in a small scale project. For this reason, a mathematical model and proof of concept design using hydrostatic head generated by elevation and venturi ejection for use by the condenser is developed along with the equations needed to predict the changes to the system. These equations were used to create software to predict efficiency as well as lay down the foundation for future improvements of the system.
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Mazyan, Walid Ibrahim. "Increasing efficiency of particle separation in natural gas cyclones using passive and active enhancements." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/61486.
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Natural gas goes through several processes ranging from extraction, treatment, liquefaction and regasification. Among these processes, treatment, specifically the removal of solid particles, has a crucial role due to its impact on annual maintenance and efficiency of downstream equipment and processes. In essence, solid particles need to be removed at a high efficiency without increasing the pressure drop and hence power consumption in the system. Cyclone separators have been used to remove large solid particles through centrifugal forces. The main disadvantage of cyclones is their efficiency, especially for particles below 5 micrometer. Numerous studies have been conducted in improving the separation efficiency of cyclones by either spraying a mist of water or changing their geometry to increase the centrifugal forces. The main disadvantage of the majority of the geometrical modifications is the fact that they cause a significant increase in the pressure drop (at least by 15%). The mist approach, increasing the density of the particles and hence the efficiency, relies on water which adds additional cost.
This research focuses on the implementation of active and passive modifications to enhance the separation efficiency of cyclones without increasing the pressure drop. The active modifications include the addition of electrostatic and magnetic forces, effects of which are studied theoretically and experimentally. The passive method involves addition of a tangential collecting chamber at the conical section. The effect of such a modification is studied thoroughly based on experiments and CFD modeling. The theoretical and experimental investigation of the electrostatic and magnetic effects show an increase in the separation efficiency of 34% and 24% for 4-micrometer particles, respectively. The results of the CFD analysis and experimental study for the passive modification (i.e., the additional chamber) suggest an increase of maximum 26% for 4-micrometer particles. The CFD results conducted for a range of particles also suggest that such a geometrical modification can increase the efficiency by 51% for 1-micrometer particles for which the increase in the pressure drop increase is only 8% (half of the minimum value reported before). These increases in the efficiency will make the cyclones a viable separator with minimum maintenance costs.Graduate Studies, College of (Okanagan)
Graduate
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Patel, S., and Uliana Ivanivna Marusyk. "The modern possibilities of increasing the efficiency of basic therapy of children’s bronchial asthma." Thesis, Буковинський державний медичний університет, 2013. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/6419.
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Sindall, Rebecca Clare. "Increasing the efficiency of anaerobic waste digesters by optimising flow patterns to enhance biogas production." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5636/.
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Anaerobic digestion is used to stabilise sewage sludge and produce biogas. Whilst the need to mix digesters is well-recognised, the level of mixing required and its effects on biogas production are not clear. Here, the effects of mixing speed in mechanically-mixed lab-scale digesters on biogas production are considered. For the first time, positron emission particle tracking was used to visualise flow patterns in lab-scale digesters at different mixing speeds. Computational fluid dynamics models were then built to identify the turbulence characteristics. Four lab-scale digesters were run for four months at different mixing speeds and key indicators of digester stability and microbiological population were recorded alongside gas production. Increased mixing speed leads to higher levels of turbulence and in these digesters, increasing the mixing speed reduces the stability of the methane generation process and accordingly has a detrimental effect on the gas production. Similarly, the abundance of methanogenic communities was adversely affected by increasing mixing speeds. However, the unmixed digester produced less biogas than the digester mixed at a low speed, due to uncontrolled digestion. As such, for these digesters, minimal mixing represents the ideal scenario. By considering the velocity gradient in the digester as a surrogate for turbulence, a threshold of 6 8 s-1 was identified. Below this threshold, increased mixing was beneficial but increasing mixing above the threshold was detrimental to digester stability and gas production.
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Guimarães, Gelton Geraldo Fernandes. "Evaluation of oxidized charcoal and urease inhibitors for increasing the efficiency of urea-based fertilizers." Universidade Federal de Viçosa, 2015. http://www.locus.ufv.br/handle/123456789/10342.
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A ureia pode apresentar baixa eficiência agronômica quando aplicada na superfície do solo, fato atribuído à intensa volatilização de NH 3 . Devido à predominância da ureia no mercado de fertilizantes nitrogenados, nas últimas décadas, tem-se buscado alternativas para o controle da hidrólise de ureia e, assim, prolongar o fornecimento de N para a absorção das culturas. Inibidores da urease tem recebido a maior parte da atenção, particularmente N-(n-butil) tiofosfórico triamida (NBPT) que é comercializado como Agrotain ® . Alternativamente, cobre e zinco podem ser utilizados para inibir a atividade da urease, tendo a vantagem de fornecer micronutrientes as plantas. Outra alternativa que vem sendo estudada é o emprego de compostos com elevada CTC e com alto poder tampão de acidez, como o carvão oxidado, com o propósito de prolongar a disponibilidade do NH 4+ no solo proveniente da hidrólise da ureia. A eficiência do carvão oxidado (OCh, 150 g kg -1 fertilizante) foi avaliado quando aplicado com ou sem Cu e/ou Zn (~0,5-2 g kg -1 fertilizante) em relação ao uso de ureia sem alterações, para aumentar a absorção de N pela forrageira Capim-mombaça (Panicum maximum). A forragem foi cultivada em casa de vegetação em Latossolo de textura média, sendo o material vegetal colhido aos 5, 14, 28, 42 e 56 dias após a aplicação superficial de 15 N na forma de grânulos de ureia com ou sem OCh, enriquecido ou não com Cu e/ou Zn, para determinação da produção da matéria seca, do teor e conteúdo de N e de 15 N nas plantas proveniente da ureia. Amostras de solo foram também coletadas em conjunto com a primeira e quarta colheita do material vegetal, para determinação da concentração das frações trocáveis de NH 4+ e NO 3 ‒ . Nas condições estudadas, a produção de matéria seca não foi afetada pelo uso de OCh com Cu e/ou Zn; no entanto, a disponibilidade de NH 4+ foi prolongada pela presença de OCh. A aplicação da ureia com Zn aumentou significativamente a absorção pelas plantas de N-ureia e o uso eficiente do N, presumivelmente refletindo a interação antagonista de Zn com superfosfato que foi aplicado para prevenir a deficiência de P. Também foi feita uma comparação dos efeitos de OCh e NBPT na transformação de N-ureia no solo. Para este propósito, quatro solos com diferentes texturas e CTC foram incubados durante 0, 1, 3, 7 e 14 dias após a aplicação de 15 N-ureia misturada ou não com OCh (150 g kg -1 fertilizante) ou NBPT (0,5 g kg -1 fertilizante). Após cada período de incubação, foi determinada a recuperação do 15 N na forma de NH 3 volatilizada, do N trocável (NH 4+ , NO 3 ‒ e NO 2 ‒ ) e do N imobilizado. O OCh teve pouco efeito sobre qualquer parâmetro medido; no entanto, a eficácia do NBPT no retardamento da hidrólise da ureia conduziu a um acúmulo gradual de NH 4+ que reduziu a volatilização de NH 3 , o acumulo de NO 2 ‒ e a imobilização de N- ureia.
Urea fertilizer can have a low agronomic efficiency when applied to the soil surface, due to N losses through NH 3 volatilization. Because of the predominance of urea in the commercial fertilizer market in recent decades, different approaches have been proposed for controlling the hydrolysis of urea and thus prolong the availability and supply of N for crop uptake. Urease inhibitors have received most of the attention, particularly N- (n-butyl) thiophosphoric triamide (NBPT) that is marketed as Agrotain ® . Alternatively, copper and zinc can be used to inhibit urease activity, which has the advantage of supplying plant-essential micronutrients. Another possibility, currently under investigation, is the use of compounds with high CEC and buffering capacity, such as oxidized charcoal, to prolong the availability of NH 4+ released in soil by urea hydrolysis. The efficiency of oxidized charcoal was assessed (OCh, 150 g kg -1 fertilizer) when applied with or without Cu and/or Zn (~ 0.5-2 g kg -1 fertilizer), relative to the use of unamended urea, for increasing N uptake by Capim-mombaça (Panicum maximum). The forage was grown in a greenhouse on a coarse-textured Oxisol, and plant material was harvested 5, 14, 28, 42 and 56 days after surface application of 15 N urea granules with or without OCh, used alone or with Cu and/or Zn, for measurement of dry matter production, total N uptake and 15 N recovery. Soil samples were also collected along with the first and fourth harvests, to determine exchangeable NH 4+ and NO 3 ‒ concentrations. Under the conditions studied, dry matter production was unaffected by the use of OCh with Cu and/or Zn; however, NH 4+ availability was prolonged by the presence of OCh. The application of Zn with urea significantly increased plant uptake of urea N and N use efficiency, presumably reflecting the antagonistic interaction of Zn with superphosphate that was applied to prevent P deficiency. A comparison was made of the effects of OCh and NBPT on the transformation of urea N in the soil. For this purpose, four soils differing in texture and CEC were incubated for 0, 1, 3, 7 and 14 days after application of pelletized 15 N urea applied with or without OCh (150 g kg -1 fertilizer) or NBPT (0.5 g kg -1 fertilizer). After each incubation period, 15 N recovery was determined as volatilized NH 3 , exchangeable NH 4+ , (NO 3 ‒ + NO 2 ‒ )-N and immobilized organic N. The OCh had little effect on any parameter measured; however, the efficacy of NBPT in retarding urea hydrolysis led to a gradual accumulation of NH 4+ that reduced NH 3 volatilization, the accumulation of NO 2 ‒ and immobilization of urea N.
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Kvarnström, Joakim. "Increasing the efficiency of the CERN accelerators by use of Superconducting Magnetic Energy Storage (SMES)." Thesis, Uppsala universitet, FREIA, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-450949.
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This report explains how an SMES is operated and how SMES systems could be used to increase the efficiency of the CERN Large Hadron Collider (LHC) and the Future Circular Collider (FCC) as well as to reduce the very high power needs of a future Muon Collider (MC). The performance of SMES for other applications and late developments of the technique will also be described.
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Krafft, Björn. "Increasing energy efficiency of road illumination with the help of traffic detection and solar energy." Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-182758.
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This master thesis investigates if it is possible to reduce the energy consumption of roadside illumination through the use of vehicle detectors, powered by renewable energy sources. By studying existing solutions available at Trafikverket a pattern became clear. Firstly a way to detect vehicles were needed; this prompted evaluation of the most common detector types. Secondly an energy source was needed; prompting investigation and research into the subject. Lastly a prototype of the conceived system was produced to prove system viability. Among the most common types of vehicle detectors comparative testing was performed. This was to evaluate which detector should be used as part of the prototype. At the same time evaluation was done of two kinds of photovoltaic cells. This to discover which type had the greatest potential to produce energy for the prototype. Based on the results from the prototype and the evaluations the suggestion became to watch for new innovations in the subject as the current technology proved cost ineffective. As the return-on-investment became 0.019% on the entire system and 0.19% on the detector logic the system currently have little economic viability.Detta examensarbete har undersökt om ett system bestående av trafik detektorer och drivs av förnyelsebarenergi kan minska energiförbrukningen hos vägbelysning. Genom att studera befintliga lösningar hos Trafikverket blev det tydligt att mycket information behövdes. Det krävdes ett tillförlitligt sätt att detektera fordon varvid de vanligaste detektortyperna utvärderades. För att kunna driva systemet undersöktes det vilken typ av solcellsteknik som kunde användas för att tillförlitligt generera energi. Detta resulterade slutligen i en prototyp av det tilltänkta systemet. För att komma fram till vilken typ av trafik detektor som skulle användas jämfördes de vanligaste detektorerna med varandra. Den detektor som ansågs vara mest tillförlitlig inkluderades i prototypen. Samtidigt utvärderades två typer av solceller för att undersöka vilken typ som potentiellt kunde producera mest energi till prototypen. Baserat på resultaten från prototypen och jämförelsetesterna drogs slutsatsen att den nuvarande tekniken inte är kostnadseffektiv. Denna slutsats baserades på att return-on-investmet enbart var 0.019% för hela systemet och 0.19% för ett komprimerat system. Det är därför intressant att bevaka teknikmarknaden för att se när tekniken mognat till den grad att systemet blivit kostnadseffektivt.
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Simonsen, Lars-Ivar H. "Increasing SpMV Energy Efficiency Through Compression : A study of how format, input and platform properties affect the energy efficiency of Compressed Sparse eXtended." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22977.
Full textAbstract:
This work is a continuation and augmentation of previous energy studies ofCompressed Sparse eXtended (CSX), a framework for efficiently executing SparseMatrix-Vector Multiplication (SpMV).CSX was developed by the CSLab at the National Technical University of Athens(NTUA), and utilizes compression to overcome a significant memory bottleneckinherent in SpMV, thus increasing performance and energy efficiency of itsexecution.SpMV is notorious within scientific computing for its low performance. However,the problem is unavoidable, as SpMV can be found within several scientificapplications. In this work, CSX is tested as the SpMV kernel in a frameworkimplementing the Conjugate Gradient Method (CG), an iterative algorithm forsolving specific linear algebra problems. CSX is also evaluated againstCompressed Sparse Row (CSR), a storage scheme widely used when executing SpMV.This work augments existing studies by evaluating properties in the formatsthemselves, in the matrices used as input and in the target platform to gainknowledge on how to maximize the benefits of CSX, as well as for what casesCSX does not prove beneficial. The work also compares the performance ofSpMV-execution on a stand-alone server known as the CARD-server to similarexecution on the Vilje supercomputer. This is done to evaluate how thedifferences between these two machines affect the results.Based on the results, it is shown that CSX should be used for matrices largerthan the Last Level Cache (LLC) of the target machine and for matrices with highdegrees of clustering in their values. The best energy efficiency trade-offs arefound at eight threads on dual socket configurations, and this is shown to berelated to the amount of physical cores per CPU. Similarly, frequencythrottling is shown to increase the energy efficiency of the execution only athigh numbers of threads and at the cost of performance.Overall, CSX is shown to obtain higher energy efficiency than CSR forSpMV-execution, given a suitable problem and run configuration. Thus, it isconfirmed that CSX can be used to decrease the energy consumption of SpMVapplications.