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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.
21

Optimization of production planning and emission-reduction policy-making

Hong, Zhaofu 12 November 2013 (has links) (PDF)
This research focuses on carbon emission-reduction issues in an area where the government imposes emission-reduction policies on local manufacturers. Policymaking problems for the government and production planning problems for the manufacturers are investigated with Operations Research/Management Science (OR/MS) approaches. Two types of emission-reduction policies, including emission-cap regulation policy and emission cap-and-trade scheme, are addressed. We first discuss manufacturers' long-term strategic decision problem under the government-imposed emission-cap regulation policy. With the objective of maximizing the manufacturers' profits, Stackelberg game model is formulated to optimize their decisions on carbon footprint, wholesale price and retailer selection. The problem is proven to be NP hard and a hybrid algorithm is developed to solve the model. We then investigate manufacturers' medium-term production planning to minimize the total production and inventory holding cost, by considering emission-reduction constraints through technology selection, some of the technologies being green. The problems are shown to be polynomially solvable. Based on these results, we study the government's policymaking problems to maximize the social welfare of the area. Stackelberg game models are formulated to optimize the emission-reduction policies by anticipating manufacturers' operational decisions in response to the governmental policies. Hybrid algorithms are developed to solve the problems. For each studied problem, numerical analyses are conducted to evaluate the algorithms. The computation results show that the algorithms developed in this research are effective. Some interesting and valuable managerial insights are drawn from computational results and sensitivity analyses.
22

Optimization of production planning and emission-reduction policy-making / Optimisation de la planification de la production et des politiques de réduction des émissions de gaz à effet de serre

Hong, Zhaofu 12 November 2013 (has links)
Cette étude porte sur la réduction de l’émission de gaz à effet de serre dans une région où le gouvernement cherche à établir des politiques de régulation des industriels locaux. La définition de politiques de régulation pour le gouvernement et la planification de la production pour les industriels sont étudiées à l’aide des méthodes issues de la recherche opérationnelle et de la science de management (OR/MS). Nous considérons deux types de politiques de régulation : la politique de quotas et la politique de droits d’émission échangeables sur le marché. Nous considérons d’abord le problème stratégique d’un industriel soumis à un quota d’émission. Afin de maximiser son profit, nous construisons des modèles de jeux de Stackelberg pour optimiser l’empreinte carbone du produit, le prix de gros et la sélection de détaillants. Le problème est démontré NP-difficile et un algorithme hybride est développé pour le résoudre. Nous étudions ensuite la planification de la production en moyen terme pour minimiser le coût total de production et de stockage, en prenant en compte les contraintes liées à la réduction d’émission à travers une sélection de technologies dont certaines sont vertes. Nous démontrons que ces problèmes peuvent être résolus en temps polynomial. A partir de ces résultats, nous étudions la définition de politiques de réduction d’émission par le gouvernement afin de maximiser le bien-être sociétal de la région. Des modèles de jeux de Stackelberg sont formulés pour optimiser les paramètres de ces politiques, en anticipant les décisions opérationnelles des industriels locaux en réaction à ces politiques. Des algorithmes hybrides sont proposés pour résoudre le problème. Pour chaque problème étudié, nous menons des expériences numériques pour évaluer les algorithmes développés. Les résultats expérimentaux montrent l’efficacité de ces algorithmes. Ils permettent aussi, grâce à des analyses de sensibilité, de tirer des renseignements managériaux intéressants. / This research focuses on carbon emission-reduction issues in an area where the government imposes emission-reduction policies on local manufacturers. Policymaking problems for the government and production planning problems for the manufacturers are investigated with Operations Research/Management Science (OR/MS) approaches. Two types of emission-reduction policies, including emission-cap regulation policy and emission cap-and-trade scheme, are addressed. We first discuss manufacturers’ long-term strategic decision problem under the government-imposed emission-cap regulation policy. With the objective of maximizing the manufacturers’ profits, Stackelberg game model is formulated to optimize their decisions on carbon footprint, wholesale price and retailer selection. The problem is proven to be NP hard and a hybrid algorithm is developed to solve the model. We then investigate manufacturers’ medium-term production planning to minimize the total production and inventory holding cost, by considering emission-reduction constraints through technology selection, some of the technologies being green. The problems are shown to be polynomially solvable. Based on these results, we study the government’s policymaking problems to maximize the social welfare of the area. Stackelberg game models are formulated to optimize the emission-reduction policies by anticipating manufacturers’ operational decisions in response to the governmental policies. Hybrid algorithms are developed to solve the problems. For each studied problem, numerical analyses are conducted to evaluate the algorithms. The computation results show that the algorithms developed in this research are effective. Some interesting and valuable managerial insights are drawn from computational results and sensitivity analyses.
23

Barriers and opportunities for implementation of Clean Development Mechanism in South Africa: a case study of Gauteng Municipalities

Ntuli, Princess Ntombifuthi 05 November 2012 (has links)
M.Phil. / Clean Development Mechanism (CDM) can be defined as one of the project-based mechanisms established under the Kyoto protocol mechanism as a supplementary measure to assist Annex 1 parties meet their emission reduction targets through investing in project activities that reduce Greenhouse Gas (GHG) emissions and contribute to sustainable development in Non–Annex 1 countries. These projects reduce GHG emissions and generate credits called Certified Emission Reductions (CERs) that the Annex 1 party can use to meet their emission reduction obligations under the Kyoto Protocol [Curnow & Hodes, 2009]. While countries such as China and India have benefited remarkably from the CDM, African countries (including South Africa (SA)) have failed to maximise the financial benefits offered by this mechanism. Even though South Africa is leading, in terms of the number of registered CDM projects in Africa, it is still lagging far behind other developing regions in this regard. The South African leaders in CDM project development are in the private sector. This research aims to identify the constraints that inhibit large scale implementation of CDM projects by Gauteng Municipalities and to investigate the reasons why South African municipalities are lagging behind the private sector in CDM project development, and identify opportunities for further development of CDM projects. This identification was achieved by compiling a list of known barriers (then investigating these barriers together with a number of other factors that may impact negatively on the CDM market in South Africa) The study was conducted using qualitative research techniques, which utilises methods such as participant observation, in-depth interviews and/or focus groups. Three different groups of respondents were identified: (i) the European CER buyers; (ii) the project developers/ CDM consultants in South Africa; and (iii) the Gauteng municipal officials responsible for CDM project development. A separate questionnaire was compiled for each of the three target groups, with purpose of drawing conclusions about the prevailing status of the South African CDM market from the perspectives of these three different groups. Three previous studies have been conducted to investigate the barriers of implementing CDM in South Africa, examining the problem from various perspectives. Little et al. [2007] conducted a study that focused on the inhibiting and facilitating factors affecting the implementation of CDM by South African industries. Wilson [2007] focused on the barriers against and drivers for the implementation of CDM within the Nelson Mandela Bay Municipality - this study drew conclusions about CDM implementation in municipalities based on the experiences of this single municipality. Winkler and van Es [2007] dealt with the opportunities and constraints of the CDM implementation in energy efficiency projects throughout South Africa.
24

Spatial Planning Approach for supporting Climate Commitments at a local level : the case of Mumbai Metropolitan Region, india / ローカルレベルでの気候目標達成を目指した空間計画手法 -インド・ムンバイ大都市圏の事例ー

Sonam, Sahu 24 September 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第22103号 / 地環博第189号 / 新制||地環||37(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 西前 出, 教授 柴田 昌三, 准教授 SINGER JANE / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
25

Měření vlastností stíněných komor EMC / Measurement of anechoic chambers

Švec, Marek January 2009 (has links)
This Master’s project deals with general aspects and possible solution of effective shielded cover and cell/chamber shielding measurement for needs of electromagnetic compatibility EMC on the basis of available norms and standards. Electromagnetic shielding is one of the most anticlutter means of EMC. Its main task is reduction of disturbing emission at the side of sources of disturbing signals as well as electromagnetic resistance increase at the side of disturbing signal receivers. Shielding is considered to be an important structural means to reduce electromagnetic field referring to a defined space part. Technical means for achieving the given goals are called shielded covers or shielded cells/chambers. Shielding is one of highly effective methods related to electromagnetic protection, for instance against power/output disturbance. To express the shielding quality so called shielding effectiveness SE is used. It represents logarithmic rate of shielding coefficient that is defined by the intensity ratios of electric and magnetic fields in a certain point of the shielded space to electric or magnetic field intensity incident/impinging on the shielded screen or wall.
26

Emissionen aus Haltungssystemen für Legehennen

Lippmann, Jens 15 October 2014 (has links)
Im Zeitraum von 2010 bis 2012 wurden Fragestellungen zu Voliere-(VO) und Kleingruppenhaltungssystemen (KG) für Legehennen durch einen vom BMEL geförderten Forschungsverbund untersucht. Das LfULG untersuchte die Stallluft und Emissionen in jeweils zwei Ställen dieser Systeme. Dabei wurden Herdengrößen kleiner und größer 15.000 Hennen abgebildet. Neben Lufttemperatur und Luftfeuchte wurden luftgetragene Stallraumlasten (Gase, Stäube und mikrobielle Bestandteile) in der Stall- und Abluft untersucht und Ableitungen für die Emissionen erarbeitet sowie Managementempfehlungen abgeleitet. Im Ergebnis wurden für Ammoniak 23 bzw. 26 g (KG) und 71 bzw. 67 g (VO), für Gesamtstaub 35 bzw. 37 g (KG) und 246 bzw. 128 g (VO), für Bakterien 10 11 kbE (KG) und 10 12 kbE (VO) sowie für Endotoxine 10 8 EE (KG) und 10 9 EE (VO) als Emissionsfaktoren je Tierplatz im Jahr ermittelt.
27

Emissionsminderung in der Legehennenhaltung

Lippmann, Jens 29 August 2007 (has links)
Untersuchungen zur Wirksamkeit emissionsmindernder Maßnahmen bei alternativen Legehennenhaltungsverfahren zur Reduzierung der Gase, Stäube und Keimbelastung
28

CDM projects and China’s CO2 emission reduction in 2006-2020

Jikai, Zhang January 2010 (has links)
The Clean Development Mechanism under Kyoto Protocol created a new age for current global emission situation. China, who owns over one third of the whole CDM projects in the world, occupies the main part of CDM development. As one of the biggest and most active economy, China declared that they would reduce their carbon emission by 40%-45% per unit GDP in 2020 compared with the 2005 level, in which CDM has the chance to highlight its value. By the day 28 April 2010, there are 814 registered CDM projects distributed in different provinces in China mainland and this number is still increasing rapidly. Because of large number of CDM projects and the significantly distinct situations in different regions of China, the author chooses two provinces, Shandong and Shaanxi, in east and west of China respectively, as representative samples to do this study. This essay investigates the current situation of CDM projects in those two provinces, and studies the contribution of these projects to emission reduction of Shandong and Shaanxi provinces in last and the next several years. The result shows that CDM projects do contribute to future potential emission reduction but their contribution are limited in these two provinces.
29

A technique for multi-attribute utility expansion planning under uncertainty: with focus on incorporating environmental factors into the planning process

Castro, Amulfo de 06 June 2008 (has links)
Within the past two decades, the planning arena has changed considerably and increasing awareness of the impacts of utility generation, intensifying pressure from the public and regulators, and growing competition from other energy and electricity suppliers have made the utility planning process rather complex. The variety of players in utility planning has introduced new priorities and a new set of competing objectives. Increased resource scarcity, the requirement for economic efficiency and the need to view the electricity production and utilization process in its entirety also necessitate an integrated resource planning approach, resulting in a wider array of expansion alternatives that must be evaluated. Another characteristic that makes planning so complicated is the uncertainty in the factors that influence the cost of the power system plan. Public concern for the environment has resulted in a series of legislations for controlling emissions of acid rain precursors (SO₂ and NO<sub>x</sub>) and other pollutants. More and more regulators are also requiring electric utilities to internalize environmental externalities in their planning processes. The potential for new legislation on currently uncontrolled effluents like CO₂ likewise remains. There is thus a need to examine the modeling of emissions that would reflect not only the cost of control but the environmental impacts of these emissions as well. This thesis combines the features of the trade-off and decision analysis techniques to address the multiplicity of objectives and the uncertainties of planning. It draws on Saaty's analytic hierarchy process (AHP) and the interdependent data analysis (IDA) technique developed at Virginia Tech to develop priority weights among objectives and probability distributions of uncertainties. It elucidates the relationship between the competing techniques of trade-off analysis and the method of weights in terms of the economic theory of the firm. The confidence intervals determined with the IDA technique are then used to obtain a range of alternatives that satisfy the requirements of both approaches for evaluation by the decision maker (DM). Special attention is given to the environmental impacts of the generation plan and the model accounts for these issues as attributes in the planning process as well as being legislation uncertainties. / Ph. D.
30

Study of the association of premixed and diffusive combustion processes on the combustion and pollutant emissions in a mid-size Diesel engine

Arthozoul, Simon Jean Louis 02 May 2016 (has links)
[EN] The main objective of this thesis is the analysis and comprehension of the association of two different combustion concepts (premixed and diffusive combustion) on the pollutant emissions and engine performance in a mid-size Diesel engine. The evaluation is performed at mid and high load conditions, where the implementation of premixed combustion is generally challenging. The association of the two combustion modes is hard to attain in a conventional Diesel engine, especially the preparation of the premixed charge with early pilot injection. Therefore, the approach followed during the study has been divided in two main steps: first, the bibliography on the subject is reviewed and two strategies avoiding the main issues mentioned in the literature are grossly evaluated in order to estimate their potential for emission reduction. Second, a deeper study of the combustion processes and emissions formation is performed, focusing only on the partially premixed combustion strategies that actually have the potential for emissions reduction. Along the second part of the study, the association of premixed and diffusive combustion is evaluated together with variation of conventional calibration parameters such as the intake oxygen concentration (via exhaust gas recirculation), the boost pressure and the start of the main injection timing, at different engine speed and load conditions. A cross analysis of the results obtained is performed in order to understand the key reasons that permit the reduction of the pollutant emissions with this strategy. In a final part of the thesis, the partially premixed combustion strategies studied are confronted with the challenges they might face when really considered for their introduction in a production engine (oil-dilution, noise...) to finally conclude on their technological potential. / [ES] El objetivo principal de la Tesis es el an álisis y la comprensi ón de la asociaci ón de dos conceptos de combusti ón diferentes (combusti ón en premezcla y por difusi ón) en las emisiones contaminantes y las prestaciones en un motor Diesel de cilindrada media. La evaluaci ón se realiza en condiciones de media y alta carga, en la cuales la implementaci ón de una combusti ón premezclada es generalmente complicada. La asociaci ón de los dos modos de combusti ón es dif cil de conseguir en un motor Diesel convencional, especialmente la preparaci ón de la carga premezclada con inyecci ón piloto adelantada. Por esa raz ón, el estudio se divide en dos partes principales: primero se revisa la bibliograf ía acerca del tema, centrando la atenci ón en dos estrategias que permiten evitar los principales problemas evocados en la literatura, determinando su potencial para la reducci ón de las emisiones contaminantes. En un segundo lugar, se realiza un estudio m as profundo de los procesos de combusti ón y de formaci ón de contaminantes, centr ándose únicamente en las estrategias de combusti ón parcialmente premezclada que sí tienen el potencial para reducir las emisiones contaminantes. En la segunda parte del estudio, se aborda la asociaci ón de combustiones premezclada y por difusi ón junto con la variaci ón de par ametros de calibraci on convencionales como la concentraci ón de ox ígeno en la admisi ón (por medio de recirculaci ón de los gases de escape), la presi ón de sobrealimentaci ón y el inicio de la inyecci ón principal, en diferentes condiciones de r egimen y de carga del motor. El an álisis cruzado de los resultados se realiza con el af án de entender las razones claves de los procesos que permiten la reducci ón de las emisiones contaminantes con esta estrategia. Como etapa final de esta tesis, se confrontan las estrategias de combusti ón parcialmente premezclada estudiadas con los problemas a los cuales podr ían llevar si realmente se considerar a su implementaci ón y un motor de serie (diluci ón de aceite, ruido...) para finalmente concluir sobre su potencial tecnol ógico. / [CA] L'objectiu principal de la tesi es l'an alisi i la comprensi o de l'associaci o de dos conceptes de combusti o diferents (combusti o en premescla i per difusi o) en les emissions contaminants i les prestacions en un motor Di esel de cilindrada mitjana. L'avaluaci o es realitza en condicions de mitja i alta c arrega, en las quals la implementaci o d'una combusti o premesclada es generalment complicada. L'associaci o dels dos modes de combusti o es dif cil d'aconseguir en un motor Di esel convencional, especialment la preparaci o de la c arrega premesclada amb injecci o pilot avan cada. Per eixa ra o, l'estudi es divideix en dos parts principals: primer es revisa la bibliogra a sobre el tema, centrant l'atenci o en dos estrat egies que permeten evitar els principals problemes evocats en la literatura, determinant el seu potencial per a la reducci o de les emissions contaminants. En un segon lloc, es realitza un estudi m es profund dels processos de combusti o i de formaci o de contaminants, centrant-se unicament en les estrat egies de combusti o parcialment premesclada que si que tenen el potencial per a reduir les emissions contaminants. En la segona part de l'estudi, s'aborda l'associaci o de combustions premesclada i per difusi o junt amb la variaci o de par ametres de calibratge convencionals com la concentraci o d'oxigen en l'admissi o (per mitj a de recirculaci o dels gasos d'escapament), la pressi o de sobrealimentaci o i l'inici de la injecci o principal, en diferents condicions de r egim i de c arrega del motor. L'an alisi creuat dels resultats es realitza amb l'afany d'entendre les raons claus dels processos que permeten la reducci o de les emissions contaminants amb esta estrat egia. Com a etapa final d'esta tesi, es confronten les estrat egies de combusti o parcialment premesclada estudiades amb els problemes als quals podrien portar si realment es consideraria la seua implementaci o en un motor de s erie (diluci o d'oli, soroll...) per a finalment concloure sobre el seu potencial tecnol ogic. / Arthozoul, SJL. (2016). Study of the association of premixed and diffusive combustion processes on the combustion and pollutant emissions in a mid-size Diesel engine [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63262

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