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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Calculation method based on CASMO/SIMULATE for isotopic concentrations of fuel samples irradiated in Ringhals PWR

Zuwak, Tariq Zuwak January 2012 (has links)
This is a M. Eng. degree project at Uppsala University carried out at Vattenfall NuclearFuel AB. The goal of it is to present a best estimate method based on the code package CASMO/SIMULATE for the purpose of calculating the isotopic concentrations of a specified number of isotopes in a fuel sample. The calculations done with the method shall produce small deviations from reliable measured values, which characterize the accuracy of CASMO/SIMULATE, but also simplicity based onthe computing time and handling of the amount of data is an important factor in the development of the method. The development of the method has been based on a sensitivity calculation with CASMO/SIMULATE on a number of relevant parameters affecting the isotope concentrations. The proposed method has then been applied on three samples irradiated in Ringhals 4 and Ringhals 3. At last the calculated isotopic concentrations have been benchmarked against measured data from Studsvik Laboratory. The sensitivity analyzes has shown that the parameters affecting the neutron moderation are very important for calculating the isotopic concentrations. The core axial resolution is also an important factor for the samples taken from top of the rod,where the power gradient is large. The comparison of the calculated and measured values has shown that SIMULATE, in the analysed cases, simulates a lower finalburnup. This has created a need to correct the final burnup in order to get better results in terms of lower relative deviations between the measured and calculated data.
2

Revision of the regional maximum flood calculation method for Lesotho

Makakole, Billy T. J. 12 1900 (has links)
Thesis (MEng) -- Stellenbosch University, 2014. / ENGLISH ABSTRACT: The Francou and Rodier (1967) empirical approach uses the original concept of envelope curves for the definition of the regional maximum flood (RMF). Kovacs (1980) adopted the Francou and Rodier empirical flood calculation method and applied it to 355 catchments in South Africa. He revised his study in 1988 to also include the southern portions of the Southern Africa subcontinent. No method other than the Francou and Rodier empirical flood approach in the reviewed literature was found to be suitable for the purpose of this study. Therefore the Francou and Rodier empirical approach, as applied by Kovacs in 1988, was reapplied and used in this study to update the RMF for Lesotho. Maximum recorded flood peaks were derived from annual maximum time series and an up to date catalogue of flood peaks for 29 catchments was compiled for Lesotho. The maximum recorded flood peaks were then plotted on the logarithmic scale against their corresponding catchment areas. There are 3 major river systems that divide Lesotho into hydrologically homogenous basins. Envelope curves were drawn on the upper bound of the cloud of plotted points for these 3 river basins. These envelope curves represent the maximum flood peaks that can reasonably be expected to occur within the respective river basins in Lesotho. / AFRIKAANSE OPSOMMING: Francou en Rodier (1967) se empiriese benadering maak gebruik van die oorspronklike konsep van boonste limiet kurwes vir die definisie van die streeks maksimum vloed (SMV). Kovacs (1980) het die Francou en Rodier empiriese vloed berekening metode toegepas op 355 opvanggebiede in Suid-Afrika. Hy hersien sy studie in 1988 om ook die suidelike gedeeltes van die Suider-Afrikaanse subkontinent in te sluit. Geen ander metode as die Francou en Rodier empiriese vloed benadering is in die literatuur gevind wat as geskik aanvaar kan word vir die doel van hierdie studie nie. Daarom is die Francou en Rodier empiriese benadering, soos toegepas deur Kovacs in 1988, weer in hierdie studie toegepas en gebruik om die SMV metode vir Lesotho op te dateer. Maksimum aangetekende vloedpieke is verkry vanuit jaarlikse maksimum tyd-reekse en ʼn opgedateerde katalogus van vloedpieke vir 29 opvanggebiede saamgestel vir Lesotho. Die maksimum aangetekende vloedpieke is grafies aangetoon op logaritmiese skaal teenoor hul opvanggebiede. Daar is 3 groot rivierstelsels wat Lesotho in hidrologiese homogene gebiede verdeel. Boonste limiet kurwes is opgestel om die boonste grens van die gestipte punte vir hierdie 3 gebiede aan te toon. Hierdie krommes verteenwoordig die maksimum vloedpieke wat redelikerwys verwag kan word om binne die onderskeie rivierstelsels in Lesotho voor te kan kom.
3

The Development Of A Building Energy Performance Evaluation Program (enad) For Architectural Design Process

Cakici, Fatma Zehra 01 January 2013 (has links) (PDF)
Energy performance in buildings has become one of the most broadly debated subjects in contemporary architecture / and current legislation has emphasized its importance by requiring buildings to possess an energy performance certificate. Due to the technological advances in computational tools, it is possible to analyze the energy performance of buildings before construction starts / however most energy performance evaluation tools, requiring complex solid models and high technical knowledge in the field, can be used only during the post design phases. Since any design decision has an important effect on the energy performance of a building, evaluation tools should be used from the very beginning of the design process. In this dissertation, a building energy performance evaluation program, entitled the Energy performance Advisor (EnAd), was developed for evaluating the energy performance of buildings considering not only the legal framework of Turkey, but also the building design process. The program does not need advanced expertise, and was developed to be usable in any phase of the design process. The program, using the monthly calculation method of TS EN ISO 13790, was developed based on the European Union Directive on Energy Performance in Buildings (EPBD) and the current Turkish legislation on the subject. EnAd integrates the legal framework with the energy performance criterion into the building design process, while providing rapid feedback on energy performance and related legislation, and guiding the designer to improve design decisions. This dissertation has also shown the effects of building size, exposed surfaces, ventilation and infiltration, window-wall ratio, U-values, set-point temperatures and temperature differences between the outside and inside spaces on energy performance of buildings through generic case studies while searching the reasons for discrepancies between the results derived from the four evaluation tools, three of which is highly acknowledged energy performance evaluation tools. The validity, reliability, precision and usability of EnAd as a design-support tool has been proved through the usability and convergence tests conducted. Finally, the thesis has pointed out the importance of the use of energy performance evaluation tools from early stages of architectural design process to achieve higher performances as well as the roles of decision makers in this process.
4

Beitrag zur Entwicklung einer verbesserten Berechnungsmethode für die Zahnfußtragfähigkeit von Zylinderschneckengetrieben / Contribution to the development of a better calculation method for the tooth root strength of worm gears

Reißmann, Jan 16 September 2016 (has links) (PDF)
Schneckenradgetriebe sind aufgrund ihrer Verzahnungsgeometrie prädestiniert für Getriebeanwendungen mit diskontinuierlichem und schwingungsbehaftetem Betrieb. Bei hohen Momenten und geringen Drehzahlen stellt dabei die Zahnfußtragfähigkeit die primäre Auslegungsgrenze dar. Das Ziel der vorliegenden Arbeit lag in der Erhöhung der Genauigkeit der Berechnungsmethoden für die Zahnfußtragfähigkeit von Schneckenrädern, auch zur Steigerung des Volumennutzwertes dieser Getriebe. Hierzu wurden alle die Tragfähigkeit des Zahnfußes beeinflussenden Parameter durch eine Vielzahl von Experimenten und FE Simulationen untersucht. Dies schließt eine genaue Analyse der Geometrie von Schneckengetrieben, deren Fertigung und Einbausituation, die verwendeten Werkstoffe und deren Beanspruchung mit ein. Auf dieser Basis gelang neben der Entwicklung eines vergleichsspannungsbasierten analytischen Berechnungsverfahrens die Erstellung eines örtlichen Berechnungskonzeptes nach dem Kerbspannungskonzept. Hiermit konnte die Einschätzung der Zahnfußtragfähigkeit bei der Neuentwicklung und die Optimierung von Getrieben verbessert werden. / Worm gears are well suited for gearbox applications in environments with discontinuous conditions and mechanical vibrations. In the case of high torque and low speed, the tooth root strength is the primary design limit. The aim of the present paper is to improve the accuracy of the calculation methods for the tooth root strength of worm wheels. To reach this, all parameters which affects the strength of the tooth root were examined. This includes the geometry, the manufacturing, the materials and the stresses of worm wheels. Through this investigation, the development of a new analytical calculation method based on the equivalent stress concept could be done. Furthermore, a local calculation method based on the notch stress concept was developed. Thus, the forecast of the tooth root strength of worm wheels for redevelopment and optimization could be improved.
5

Protingos namų informacijos valdymo sistemos sudarymas ir tyrimas / Smart home information management system development and research

Dmuchovskis, Andrius 04 November 2013 (has links)
Sparčiai augant modernių būstų skaičiui, taip pat sparčiai auga šių kompiuterizuotų būstų informacijos valdymo sistemų poreikis. Šios sistemos įvairiais jutikliais renka informaciją apie būsto patalpų temperatūrą, drėgmę ir kt. Ši informacija dažniausiai yra kaupiama skirtingais būdais atskirose posistemėse, todėl vartotojui nėra paranku stebėti kiekvienos posistemės duomenis. Informacijos valdymo sistemos leidžia vartotojui stebėti visą savo kompiuterizuoto būsto sistemų informaciją vienoje vartotojo sąsajoje. Informacijos valdymo sistemos, panaudodamos esamus būsto informacijos sistemų duomenis, gali pateikti vartotojui išteklių naudojimo rekomendacijas, atsižvelgdamos į vartotojo suformuotus reikalavimus – paskaičiuoti mėnesio šildymo kainą vartotojui nurodant norimą patalpos temperatūrą įvertinant išteklių kainas. Šio darbo objektas – informacijos valdymo sistema įterpta į kompiuterizuoto būsto sistemą. Darbo tikslas – sukurti protingos namų informacijos valdymo sistemos prototipą. Sistemą sudaro programiniai agentai, kurie pagal vartotojo poreikius sugeba surinkti ir pateikti informaciją vartotojui ir pagal tai priimti sprendimus. Darbe tiriamos programinių agentų savybės, informacijos, kurią naudoja agentai, surinkimo metodai, jų (agentų) kasifikacija ir tipologija, taikymas informacijos valdymo sistemose. Darbas susideda iš probleminės srities analizės, sistemos modelio ir eksperimentinio tyrimo. / With the rapid growth of automated houses, there is same rapid growth of these houses information management systems needs. Systems with various sensors gather information about zones temperature, humidity etc., information about other systems resources (e.g. heating services, electricity prices) is also gathered.Most of the time this information is being saves by different methods in separate systems, and that is not very handy for a user to track all data from different systems sources. Information management systems let the user to see all his automated house systems information in one graphical user interface. Information management systems, using existing house information systems data, can provide user resource usage recommendations, considered with users needs. E.g. calculate months heating costs, when user provides desired zone temperature, using resource prices to achieve this goal. Master thesis object – information management system, working inside home automation system. Master thesis goal – to create smart house information managent systems prototype. System consists of software agents, which, according to users’ needs, can gather and deliver information for user. Master thesis studies software agent features, agent information gathering methods, their (agents) classification and typology, usage in information management systems. Master thesis consists of three parts: problem analysis, system model and experiment.
6

Augalininkystės produkcijos savikainos skaičiavimo metodika / Methodics of Plant Production Cost Calculation

Dereškaitė, Rima 24 May 2005 (has links)
Research object – agricultural enterprises. Research subject – methodics of plant production cost calculation. Research aim – to analyze references and practical methods employed in plant produce cost calculation and to propose methodics improvements of plant production cost calculation. Objectives: 1) to analyze the essence of expenditure and production cost; 5) to examine the structure of production cost and to substantiate the expedience of expenditure calculation into cost; 6) to study methodics of plant production cost calculation in agricultural enterprises; 7) to submit proposals for improvement methodics of plant production cost calculation based on references study and research results. Research methods – logical and comparative analysis and synthesis of literature by Lithuanian and foreign authors, questionnaire questioning of agricultural enterprises, methods of logical and graphic modeling. After the study of produce cost essence, indices and their composition, calculation system and plant produce cost calculation methodology applied at agricultural enterprises, proposals were submitted for improvement methodics of plant production cost calculation.
7

Kalkulace výrobních nákladů ve firmě LEXMARK, a.s. / Calculation Production Costs in Firm LEXMARK, Inc .

Matelová, Bohdana January 2009 (has links)
MATELOVÁ, B. Kalkulace výrobních nákladů společnosti Lexmark, Brno. 2009 This thesis deals with the analysis of the Price sheet used by company Lexmark and based on this analysis I recommend the potential changes of this Price sheet. The price sheet is a tool for the re-invoicing of production cost between Lexmark and production subcontractors. The first part is dedicated to the theory of cost management. The next part is practical. I present the company Lexmark, describe the structure of Price sheet, production costs and cost calculation for all types of products. I close the practical part with the specification of Price sheet strong and weak points. Base on the analysis I recommend the potential changes of Price sheet, some of them are applicable immediately and next in a longer period.
8

Analýza a návrh kalkulačního systému v podniku / Analysis and Design of Corporate Tracing Policy

Zadražil, Vojtěch January 2011 (has links)
This diploma thesis deals with analysis and design of corporate tracing policy. The main goal of the work is to describe calculations as an auxiliary tool for base-point pricing and for the fixing of company costs its management and efficiency. In the theoretical part diverse calculation systems currently used in companies are defined. Further, all kinds of expenses occuring in a firm are characterized. The practical section´s concern is costing of forgings produced in company Moravské kovárny, a.s. The origin of price of particular forgings and the costs that rise in this company are analyzed. Finally, the proposal of a new method of pricing and a way of elaboration of calculations for particular forgings are described.
9

Valdymo apskaitos modelis vidutinio dydžio gamybinėje įmonėje / Management accounting model in the medium manufacturing company

Jasiūnaitė, Reda 25 June 2014 (has links)
Anksčiau vadybininkai, spręsdami strateginius ir einamuosius įmonės veiklos klausimus, naudojosi finansine apskaita. Tačiau finansinės apskaitos dokumentai pateikia pernelyg apibendrintus duomenis apie įmonės veiklą ir neleidžia susieti daromų sprendimų gamybos bei pardavimų srityje su gaunamu veiklos rezultatu. Vadovui sprendimams priimti reikalingą informaciją teikia įvairūs šaltiniai. Pagrindinis iš jų – įmonėje įdiegta valdymo apskaitos sistema, kurioje sukaupti ir apdoroti duomenys pateikiami įmonės rengiamose vidaus ataskaitose. Valdymo apskaita yra specifinė kiekvienoje įmonėje, tačiau tam tikroms įmonių rūšims pagal dydį ir veiklą galima išskirti būdingus bendrus metodus bei taisykles. Lietuvoje vyrauja mažos ir vidutinės įmonės, tačiau lietuvių autorių (J. Mackevičius, 2003; A. Jurkštienė, 2002; I. Zabielavičienė, 2005; V. Jagminas, 2006 ir kt.), rašančių valdymo apskaitos klausimais, darbuose valdymo apskaitos sistemų bruožai yra nagrinėjami bendrai, nepabrėžiant, kurie iš jų tinkamiausi ir geriausiai pritaikomi mūsų šalies įmonėse. Taigi šiame darbe siekiama išskirti pagrindinius valdymo apskaitos sistemos bruožus vidutinio dydžio gamybinėje įmonėje. Tyrimo objektas – valdymo apskaita vidutinio dydžio gamybinėje įmonėje. Tyrimo tikslas – išnagrinėjus galimybes praktiškai taikyti valdymo apskaitos teorines nuostatas sudaryti optimalų valdymo apskaitos modelį efektyviam veiklos vykdymui vidutinio dydžio gamybinėje įmonėje. Tikslui pasiekti iškelti tokie svarbiausi... [toliau žr. visą tekstą] / Previously, in order to solve company’s strategic and current problems, managers were using financial accounting data. Unfortunately, financial accounting propose too general data, how company works, and does not allow to relate decisions in manufacturing and selling with the company’s work results. When the manager needs to make a decision, the information he gets from different sources. The main is – company’s management accounting, where stored and proceeded data are given in company’s internal reports. In every company management accounting has it‘s specifics, but according to company’s measures and activities you can separate general methods and rules. In Lithuania the most common are small and medium companies, unfortunately Lithuanian authors (J. Mackevičius, 2003; A. Jurkštienė, 2002; I. Zabielavičienė, 2005; V. Jagminas, 2006 ir kt.), who are writing about management accounting, review the main features of management accounting system in very general way and do not define witch of them is the most proper and adopted in Lithuanian companies. In this paper I will try to separate the main features of management accounting system in medium company. Research object – management accounting in medium manufacturing company. Purpose of research – to make an optimal management accounting model for effective development of medium manufacturing company, after opportunities to apply management accounting theoretical aspects were explored. The main goals: • to describe definition... [to full text]
10

Vers une caractérisation spatiotemporelle pour l'analyse du cycle de vie / Towards a Spatiotemporal Characterization for Life Cycle Analysis

Beloin-Saint-Pierre, Didier 03 December 2012 (has links)
Cette thèse présente différents développements à la méthode analyse de cycle de vie (ACV) afin d'améliorer le niveau de considération des spécificités spatiotemporelles lors de la modélisation de systèmes. Ces développements abordent la question de la caractérisation des flux décrivant les systèmes. La discussion débute par une analyse des développements récents de la méthode ACV en ce qui concerne la considération des spécificités spatiotemporelles dans les différentes phases de cette méthode. Cette analyse identifie des lacunes quant à la pertinence des modes de caractérisation spatiale et temporelle existants. Un nouveau mode de caractérisation spatiotemporelle est alors pro-posé. La représentativité du système modélisé, le potentiel de précision de la caractérisation et le temps de travail nécessaire à la modélisation de différents systèmes sont trois critères importants qui ont été considérés pour la création de ce nouveau mode de caractérisation spatiotemporelle. Le nouveau mode proposé permet en particulier d'améliorer la généricité des processus définissant des systèmes dans différentes bases de données. Celui-ci permet ainsi de diminuer l'augmentation inévitable du travail lié à la caractérisation temporelle des systèmes. Le nouveau mode de caractérisation temporelle requiert toutefois une modification importante de la méthode de calcul des inventaires cycle de vie en raison de l'utilisation de distributions temporelles. La faisabilité de l'utilisation de ce nouveau mode et de la nouvelle méthode de calcul d'inventaire est ensuite démontrée par leurs mises en œuvre pour différents cas d'études de production d'énergie à partir de sources renouvelables. Les deux cas d'études retenus permettent de souligner l'intérêt d'une telle caractérisation spatiotemporelle accédant ainsi à une modélisation plus représentative des systèmes en fonction du niveau de précision retenu. Avec cette nouvelle approche nommée ESPA+, l'accès à ce niveau de représentativité s'accompagne cependant d'une diminution du potentiel de complétude de l'analyse. En effet, la méthode de calcul permet difficilement de dynamiser la totalité des systèmes modélisés. / This thesis presents various developments to the Life Cycle Assessment (LCA) method to improve the consideration of spatiotemporal specificities when modeling systems. These developments handle the question of how to characterize the various systems' flows. The discussion begins with an analysis of recent developments for the LCA method regarding the consideration of spatiotemporal characteristics in different phases of this method. This analysis identifies several weaknesses on how space and time are characterized today. A new spatiotemporal characterization mode is therefore proposed to minimize the adverse effects of existing characterization modes. Representativeness of the modeled system, potential accuracy of the characterization and the amount of time necessary for system modeling are three important criteria considered for the elaboration of this new spatiotemporal characterization mode. The new mode specifically improves the “genericity” of processes which are used to model systems in different databases. This “genericity” allows a reduction in the unavoidable workload increase related to the time characterization. The new method, however, requires a major change in the method of calculating life cycle inventories due to the use of temporal distributions. The feasibility of using this new method and the method of calculating inventory is then illustrated by their implementation through different case studies related to energy generation from renewable sources. The two case studies selected highlight the relevance of considering spatiotemporal characterization to model systems in a more representative way depending on the level of preci-sion used. With this new approach, named ESPA+, this higher level of representation, however, brings a potential decrease of completeness for the analysis of the system. Indeed, it is difficult to model the spatiotemporal characteristics of a complete system.

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