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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.
401

Does IDA meet the requirements? : Evaluating the method Information Demand Analysis

Wass, Sofie, Nyberg, Camilla January 2009 (has links)
This study aims to evaluate the use of the method Information Demand Analysis (henceforth IDA) against an analysis tool. To gain empirical understanding of IDA, the method will be applied to a cooperation process between two business organisations. The research questions of the study are to investigate what can be required of a method, to identify the information demand for the above mentioned cooperation process, and to identify the strengths and weaknesses of the use of IDA. Based on a literature study an evaluation framework, which describes what can be required of a method, was developed. The evaluation framework resulted in an analysis tool, which consists of the elements: method content, method user, method context, method validation, the method creator’s requirements, and the wishes and expectations of the business organisations. The use of IDA implied scoping to delimit the problem situation and a workshop to identify the information demand. In order to gain an understanding of the use of the method IDA, and to identify the information demand, the method was applied to a cooperation process between Steel AB and Wood AB. The information demand was later represented in Extended Enterprise Modelling Language (henceforth EEML). Finally, we analysed if and how the elements in the analysis tool were reflected in IDA and identified the strengths and weaknesses of the use of the method. The strengths of IDA are that it is general and applicable on different types of business organisations. Furthermore, it has well defined concepts and the possibility of selecting appropriate concepts ensures that it is applicable on different problem situations. The business organisations, which participated in the workshop, found that IDA resulted in a holistic view and increased the understanding for each other. The weaknesses of IDA are lack of documentation of explicitly defined steps, the implications for selecting certain concepts, guidance, and explicitly described notations. Concerning the involved roles, in IDA, we request a description of them, their responsibilities, and the needed knowledge sets and skills for using the method. Since IDA still is under development we had difficulties understanding how our outcome of the method should fulfil the purpose of IDA.
402

Integrating Demand-Side Resources into the Electric Grid: Economic and Environmental Considerations

Fisher, Michael J. 01 December 2017 (has links)
Demand-side resources are taking an increasingly prominent role in providing essential grid services once provided by thermal power plants. This thesis considers the economic feasibility and environmental effects of integrating demand-side resources into the electric grid with consideration given to the diversity of market and environmental conditions that can affect their behavior. Chapter 2 explores the private economics and system-level carbon dioxide reduction when using demand response for spinning reserve. Steady end uses like lighting are more than twice as profitable as seasonal end uses because spinning reserve is needed year-round. Avoided carbon emission damages from using demand response instead of fossil fuel generation for spinning reserve are sufficient to justify incentives for demand response resources. Chapter 3 quantifies the system-level net emissions rate and private economics of behind-the-meter energy storage. Net emission rates are lower than marginal emission rates for power plants and in-line with estimates of net emission rates from grid-level storage. The economics are favorable for many buildings in regions with high demand charges like California and New York, even without subsidies. Future penetration into regions with average charges like Pennsylvania will depend greatly on installation cost reductions and wholesale prices for ancillary services. Chapter 4 outlines a novel econometric model to quantify potential revenues from energy storage that reduces demand charges. The model is based on a novel predictive metric that is derived from the building’s load profile. Normalized revenue estimates are independent of the power capacity of the battery holding other performance characteristics equal, which can be used to calculate the profit-maximizing storage size. Chapter 5 analyzes the economic feasibility of flow batteries in the commercial and industrial market. Flow batteries at a 4-hour duration must be less expensive on a dollar per installed kWh basis, often by 20-30%, to break even with shorter duration li-ion or lead-acid despite allowing for deeper depth of discharge and superior cycle life. These results are robust to assumptions of tariff rates, battery round-trip efficiencies, amount of solar generation and whether the battery can participate in the wholesale energy and ancillary services markets.
403

Modelování regionální poptávky po bydlení v ČR - teoretické přístupy a aplikace / Modelling of regional demand for housing in Czech Republic - teoretical principles and application

Pavlíček, Jiří January 2008 (has links)
This thesis is focused on simulation of demand for housing and formation of prices on the real estate market in Czech Republic. Theorethic introduction discribes microeconomic demand theory and spatial demand based on localization theory. The basic theory advences in demand for housing, that is focused on heterogeneousness, price, localization and types of living. Principal aim of this thesis is the empirical analysis and simulation of regional demand on the real estate market. Empiric analysis consists of dynamic and static model of demand for housing in Czech Republic etc..
404

Current topics in cost allocation and custom API development in IBM Cognos TM1 / Súčasné prístupy k nákladovej alokácii a vývoj typizovaného programového rozhrania v nástroji IBM Cognos TM1

Fedoročko, Peter January 2012 (has links)
Thesis is devoted to current trends in approaching cost allocation developed in IBM Cognos TM1 software. Concept, which was originally elaborated in my bachelor thesis, has recently experienced restrictions caused by increasing requirements on analytical tools and information they provide. Goal of the thesis is therefore to analyse causalities of emerging weaknesses, design and develop optimalized and reengineered solution answering current demands. Reqarding the quantitative evaluation of attained results, the thesis is extended with analysis of frameworks and standards dedicated to benchmarking of OLAP tools and their synthesis into own complex model. Proposed model specializes on measuring multiple OLAP applications across four main perspectives including performance, development, usability and financial benefits. Attained results prove, that reengineered model is faster, data richer, easier to use and appropriate for any organization with structured and algorithmic approach to cost allocation. Second half of the thesis focuses on extending the presentation layer to web browser, designing and developing of custom visualizations for most usual analytic tasks. Considering the absence of advanced application interface in IBM Cognos TM1, the thesis also includes theoretical analysis of current trends in API development and design of concept allowing communication and data transportation between applications and TM1 server. In the concluding section of the thesis, proposed concept is materialized into universal library developed in PHP and applied to novel allocation model. Leveraging the library, two exemplary interfaces for allocator operation and data consumption are implemented. Gained knowledge can serve as basis for development of additional components communicationg with TM1 in variety of projects or theoretical framework for API implementation in general.
405

Avances en Verificación y Medida de la Respuesta de la Demanda y Aplicación a su integración en Smart Grids

Roldán Blay, Carlos 01 March 2016 (has links)
[EN] The electric power industry is being shaken by a new idea that is taking shape: smart grids. Three aspects are considered keys to reach smart grids: a) The structure of the network must meet the smart grid concept, i.e. it must be resistant to failures, e.g. causing the automatic separation of any broken element without affecting the operation of the other components; it must be flexible to allow the connection or disconnection of loads and distributed generators, it must maintain efficient operation under various load conditions, and so on. b) The network should open the possibilities of participation of large and small generators as well as users, enabling new business opportunities and active participation, so that "intelligent" generation or consumption may benefit. c) All participants must have easy access to the information needed to choose the best operating strategy in each case. In regard to the first condition (a) there are significant challenges to solve: network automation, optimal design, development of new protection and control equipment, etc. It will be necessary to develop equipment adapted to new problems and new needs that will be generated in these networks. Those items of equipment should be standardised, it will be necessary to define tests to take into account issues that currently are not usually needed, such as the presence of disturbances in voltage, or others. In this sense, marginally though, the research team in which the author works has collaborated with a laboratory for electrical testing, the Flex Power Grid Lab Research Infrastructure DNV KEMA in the Netherlands, in the definition and implementation of some tests, as described in Chapter 3. Smart grids. In the second aspect (b), deep social changes are needed and, above all, regulation changes are crucial. In any case, the first step is to know how the consumption of loads is, how can demand be modified, how can small generation (mainly renewable) and energy storage influence generation, and so on. Having accurate models that provide this information is a key factor for network agents to establish their best strategies. This dissertation discusses many aspects of energy demand and the problem of controlling several resources and agents in the system operation is addressed and Chapter 3. Smart grids shows the management and control software (in which the author has collaborated during the design and development stages) of a small smart grid that exists in LabDER laboratory at UPV, where various resources are integrated according to the needs of demand, energy prices, and so on. In the third condition (c) there are also major challenges to be solved, such as mass information management and the increasing volume of data traffic that it can involve. This dissertation proposes several algorithms to facilitate treatment of the available data to optimise the management of the resources in a smart grid or to make decisions about the participation in demand response programs, as shown in Chapter 8. Energy Management Systems for Smart Customers. / [ES] La industria eléctrica de potencia está siendo sacudida por una idea que va tomando forma: las smart grids. Tres aspectos pueden considerarse claves para llegar a las smart grids: a) La estructura de la red debe responder al concepto de red inteligente, es decir, ser resistente a fallos, por ejemplo provocando la separación automática de cualquier elemento averiado sin afectar al funcionamiento del resto de la red; ser flexible para permitir la conexión o desconexión de cargas y generadores distribuidos, mantener un funcionamiento eficiente bajo diversos estados de carga, etc. b) La red debe abrir las posibilidades de participación de grandes y pequeños generadores así como de los usuarios, permitiendo nuevas posibilidades de negocio y de participación activa, de manera que la generación o el consumo "inteligentes" se vean beneficiados. c) Todos los participantes deben tener acceso fácil a la información necesaria para poder elegir la mejor estrategia de funcionamiento en cada caso. En lo que respecta a la primera condición (a) hay importantes retos por resolver: automatización de la red, diseño óptimo, desarrollo de nuevas protecciones y equipos de control, etc. Será necesario desarrollar equipos adaptados a los nuevos problemas y nuevas necesidades que se generarán en estas redes. Esos equipos deberán ser normalizados, para lo cual será necesario definir ensayos que tengan en cuenta aspectos que actualmente no suelen ser necesarios, como la presencia de perturbaciones en la tensión, u otros. En este sentido, aunque de forma marginal, se ha colaborado con un laboratorio para ensayos eléctricos, la Flex Power Grid Lab Research Infrastructure del DNV KEMA en los Países Bajos, en la definición y realización de algunos ensayos, como se indica en el Capítulo 3. Smart grids. En el aspecto segundo (b), son necesarios profundos cambios sociales y, sobre todo, legislativos. En cualquier caso, el primer paso consiste en saber cómo es el consumo de los receptores, de qué manera puede variarse la demanda, qué influencia puede tener la pequeña generación (renovable principalmente) y el almacenamiento de energía, etc. Disponer de modelos precisos que proporcionen esta información es clave para que los actores de la red puedan establecer sus mejores estrategias. En la tesis se analizan muchos aspectos relacionados con la demanda de energía y se aborda el problema del control de la participación de diversos recursos y diversos agentes en el funcionamiento del sistema y en el Capítulo 3. Smart grids se muestra el software de gestión y control (en cuyo diseño y desarrollo se ha colaborado) de una pequeña smart grid que existe en el laboratorio LabDER de la UPV, donde se integran diversos recursos en función de las necesidades de la demanda, los precios de la energía, etc. En la tercera condición (c) hay, también, grandes retos por resolver, como la gestión masiva de información y el incremento en el volumen de tránsito de datos que puede representar. En la tesis se proponen diferentes algoritmos para facilitar el tratamiento de los datos disponibles a la hora de optimizar la gestión de los recursos de una smart grid o tomar decisiones de cara a participar en programas de respuesta de la demanda, tal como puede verse en el Capítulo 8. Sistemas de Gestión Energética para Smart Customers. / [CAT] La indústria elèctrica de potència està sent sacsada per una idea que va prenent forma: les smart grids. Tres aspectes poden considerar-se claus per a arribar a les smart grids: a) L'estructura de la xarxa ha de respondre al concepte de xarxa intel·ligent, és a dir, ser resistent a fallades, per exemple amb la separació automàtica de qualsevol element avariat sense afectar el funcionament de la resta de la xarxa; ser flexible per a permetre la connexió o desconnexió de càrregues i generadors distribuïts; mantindre un funcionament eficient davall diversos estats de càrrega, etc. b) La xarxa ha d'obrir les possibilitats de participació de grans i xicotets generadors així com dels usuaris. Així, ha de permetre noves possibilitats de negoci i de participació activa, de manera que la generació o el consum "intel·ligents" es vegen beneficiats. c) Tots els participants han de tindre accés fàcil a la informació necessària per a poder triar la millor estratègia de funcionament en cada cas. Pel que fa a la primera condició (a) hi ha importants reptes per resoldre: automatització de la xarxa, disseny òptim, desenrotllament de noves proteccions i equips de control, etc. Serà necessari desenrotllar equips adaptats als nous problemes i noves necessitats que es generaran en aquestes xarxes. Aqueixos equips hauran de ser normalitzats, per a la qual cosa serà necessari definir assajos que tinguen en compte aspectes que actualment no solen ser necessaris, com la presència de pertorbacions en la tensió, o altres. En aquest sentit, encara que de forma marginal, s'ha col·laborat amb un laboratori per a assajos elèctrics, la Flex Power Grid Lab Research Infrastructure del DNV KEMA en els Països Baixos, en la definició i realització d'alguns assajos, com s'indica en el Capítol 3. Smart grids. En l'aspecte segon (b), són necessaris profunds canvis socials i, sobretot, legislatius. En qualsevol cas, el primer pas consisteix a saber com és el consum dels receptors, de quina manera pot variar-se la demanda, quina influència pot tindre la xicoteta generació (renovable principalment) i l'emmagatzemament d'energia, etc. Disposar de models precisos que proporcionen aquesta informació és clau perquè els actors de la xarxa puguen establir les seues millors estratègies. En la tesi s'analitzen molts aspectes relacionats amb la demanda d'energia i s'aborda el problema del control de la participació de diversos recursos i diversos agents en el funcionament del sistema i en el Capítol 3. Smart grids es mostra el programari de gestió i control (en el disseny i desenrotllament del qual s'ha col·laborat) d'una xicoteta smart grid que existeix en el laboratori LabDER de la UPV, on s'integren diversos recursos en funció de les necessitats de la demanda, els preus de l'energia, etc. En la tercera condició (c) hi ha, també, grans reptes per resoldre, com ara la gestió massiva d'informació i l'increment en el volum de trànsit de dades que pot representar. En la tesi es proposen diferents algoritmes per a facilitar el tractament de les dades disponibles a l'hora d'optimitzar la gestió dels recursos d'una smart grid o prendre decisions de cara a participar en programes de resposta de la demanda, tal com pot veure's en el Capítol 8. Sistemes de Gestió Energètica per a Smart Customers. / Roldán Blay, C. (2016). Avances en Verificación y Medida de la Respuesta de la Demanda y Aplicación a su integración en Smart Grids [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61302 / TESIS
406

Evaluation and Assessment of New Demand Response Products based on the use of Flexibility in Industrial Processes: Application to the Food Industry

Alcázar Ortega, Manuel 25 February 2011 (has links)
En el marco de un mercado de la electricidad con precios cada vez más altos y donde la participación de fuentes renovables de generación está jugando un papel cada vez más importante, esta tesis supone un enfoque innovador hacia la participación de recursos de demanda en mercados de operación, prestando una atención especial a segmentos industriales como el sector alimentario con un consumo energético intensivo. En primer lugar, esta tesis describe detalladamente la situación actual de los programas de respuesta de la demanda que existen en diferentes partes del mundo. Este estudio permite concluir que los consumidores no han sido tenidos en cuenta suficientemente en la fase de diseño de los programas existentes, lo que ha provocado la infrautilización de recursos de demanda que, actualmente, permanecen sin explorar. Por otro lado, los consumidores no son conscientes del valor que su flexibilidad podría tener para el sistema eléctrico en su conjunto, ignorando que puedan existir otros agentes dispuestos a pagarles a cambio de reducir sus cargas en períodos determinados. Como resultado, esta tesis desarrolla una nueva metodología para explorar y valorar nuevos mecanismos de respuesta de la demanda donde el punto de vista de consumidores, operadores de red y cualquier otro agente interesado pueda ser tenido en cuenta. Esta metodología, basada en la evaluación y análisis detallado de los procesos, proporciona a los consumidores las herramientas adecuadas para evaluar su capacidad para reaccionar al precio de la electricidad, lo que permitiría al regulador poner en valor el beneficio social de dicha flexibilidad si pudiera ser utilizada en mercados de operación, ayudándole a definir los programas necesarios para utilizar de forma adecuada el potencial identificado por los consumidores. La metodología desarrollada en esta tesis ha sido aplicada satisfactoriamente al sub-segmento de la industria cárnica, por lo que varias fábricas pertenecientes a este segmento han sido estudiadas en detalle. En concreto, la factibilidad de las acciones propuestas ha sido probada y validada satisfactoriamente en una fábrica dedicada a la producción de jamón curado en España, en la que se han evaluado diferentes estrategias de flexibilidad. Finalmente, se ha realizado una evaluación económica de la rentabilidad de la aplicación de las acciones de flexibilidad propuestas tanto para el consumidor como para el sistema eléctrico en su conjunto, donde se han considerado los precios reales de los mercados de operación en España, aun cuando los consumidores no puedan participar realmente en dichos mercados en la actualidad. / Alcázar Ortega, M. (2011). Evaluation and Assessment of New Demand Response Products based on the use of Flexibility in Industrial Processes: Application to the Food Industry [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/10078 / Palancia
407

Malaysian Natural Rubber Industry: An Econometric Analysis on the Elasticity of Supply and Demand Approaches

Mohd Ismail, Harun Mizam bin 12 1900 (has links)
The popularity of natural rubber as an important raw material was distorted in the post-World War Two period. It received heavy competition from synthetic rubber. The main purpose of this paper is to determine and to study supply elasticity and demand elasticity of natural rubber in the case of Malaysia. The main aim of analyzing the period since 1971 is that both price and quality competitiveness of Malaysian natural rubber have drastically improved. Therefore, in order for Malaysia to maintain her position as the leading producer and exporter of natural rubber in the world, supportive policies and incentives from the government would further enhance the prospects for improvements in this industry.
408

Estimating Peak Water Demand in Buildings with Efficient Fixtures: Methods, Merits, and Implications

Omaghomi, Toritseju O. 01 October 2019 (has links)
No description available.
409

Identifikace poptávky / The Identification of the Demand

Feldbabel, Vít January 2011 (has links)
The aim of this thesis is to work out demand for various kinds of commodities of current consumption by conducting a survey. From the polled data, a function of price demand elasticity of selected commodities is drawn up, on which suggestions to sellers for turnover maximization is based.
410

Human behaviour and energy demand : How behavioural science can be used to reduceenergy demand in the residential sector

Kaczmarek, Haiko January 2015 (has links)
The threat of human induced climate change is imminent. The reason is an everyincreasing demand for energy and products, producing more and more greenhousegas emissions. Everybody needs to take responsibility now. The estimations are thatwith 2% annual energy savings from residential households 12TWh and 3.3 billionmetric tonnes of CO2 can be saved per year. Greenely, a startup from KIC InnoEnergy,wants to engage residential households to change their energy behaviour athome. They combine a smartphone application with the smart meter infrastructureto reduce households energy demand. Changing behaviour is complicated and researchprior to this thesis revealed that information and economic incentives aloneare not sufficient.A simple and proven technique to change behaviour is Nudging. A gentle pushin the right direction while leaving the freedom of choice. A popular example is aprinted fly in the men’s urinal. It nudges them to aim at the fly. The cleaning costswere reduced by 80% at the Schiphol Airport Amsterdam.Without application usage change is impossible for Greenely. Their main contacttool to households is a smartphone application. The smartphone market is vast andcompetition between applications is strong. Therefore the system outline needs toprecede Nudging for ongoing engagement and long term change. To achieve thatGamification practices are implemented. It is the incorporation of game design intonon-gaming contexts to achieve engagement through motivation and fun.This master thesis is done in cooperation with Greenely and focuses on residentialdemand reduction schemas, Nudging and Gamification. The aim is to improvetheir actual application and create an outline for an improved version that promoteslong term behaviour change. The result incorporates the most suitable features fromthe relevant topics and enables long term change.

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