La industria es comúnmente vista como una fuente de degradación ambiental y de consumo de recursos, a pesar de ello es una parte vital del desarrollo social y de la creación de riqueza. Del mismo modo, los sistemas industriales causan y determinan los flujos de materias y energía a través de la sociedad. El desarrollo sostenible está asociado a todos los aspectos anteriores al englobarlos a todos.Los servicios sostenibles son aquellos que restringen el consumo de recursos y generación de residuos a un nivel aceptable considerando las existencias y las velocidades de recuperación de los recursos así como la capacidad de soporte de La Tierra. Asimismo, hacen una contribución positiva a la satisfacción de las necesidades humanas y proveen de valor económico a la empresa. La selección de procesos apropiados para la provisión de un dado servicio es el tópico principal de esta tesis.Esta tesis presenta un marco consistente para el soporte a la decisión hacia alternativas sostenibles. El marco abarca un grupo de métodos y herramientas aplicables al soporte de la decisión en cuestiones de diseño, actualización, y operación considerando criterios de sostenibilidad en términos económicos y medioambientales. Se ha enfatizado la simulación de procesos, el modelado matemático y otros métodos de estadística multivariable. El marco está materializado en un procedimiento de uso que posee cuatro pasos que imitan los de otros métodos actualmente utilizados y un set integrado de herramientas. Las herramientas usadas son en todos los casos modelos matemáticos que permiten una representación precisa de la realidad que simulan. El problema multiobjetivo resultante es resuelto usando una estrategia que permite restringir la mejor solución de compromiso. Una multitud de casos de estudio industriales muestra la forma de aplicación del marco en diferentes escenarios.El marco se ha aplicado a casos de estudios que requieren de soporte a la decisión. El caso de diseño de procesos continuos se ha incluido tratando tres casos. El primero está relacionado con la selección de opciones de tratamiento de aguas residuales en una planta de producción de ácido fosfórico considerando incertidumbre en variables operativas. Otro caso considera las decisiones relacionadas al uso de diferentes materias primas en una usina eléctrica con tecnología de gasificación. El último caso considera la optimización de las variables operativas en el diseño de un sistema de destilación reactiva. Todos los casos son modelados rigurosamente usando noveles herramientas de simulación y modelado en conjunto con otras desarrolladas para el análisis de los aspectos económicos y medioambientales de la sostenibilidad.Posteriormente, se ha estudiado el problema operacional de la selección de la planificación de producción. En este caso se ha puesto atención especial a la selección de métricas apropiadas considerando aspectos económicos, medioambientales y de eficiencia que reflejen las características secuenciales del problema. El modelo propuesto se ha construido usando herramientas de programación matemática y la producción de fibras acrílicas es la aplicación considerada.Finalmente el marco se ha aplicado al diseño y planificación de una cadena de producción. En este caso se modelan decisiones de planificación a medio y largo plazo y se las aplica a la producción de anhídrido maleico en Europa del Oeste. Dadas las características del problema se han estudiado diferentes instrumentos económicos asociados al medio ambiente, como la venta de permisos de emisión y subsidios a la producción. Esto permite mostrar las capacidades del marco para el estudio de políticas gubernamentales.Los casos de estudio muestran las diferentes compensaciones que aparecen en varios niveles de decisión. Asimismo el marco provee con un enfoque robusto para la trazabilidad y capacidad de verificación de las diferentes hipótesis de modelado, lo cual refuerza el proceso de toma de decisiones. / Industry is often seen as a source of environmental degradation and resource depletion, however it is a vital part of societal development and wealth creation. Moreover, industrial systems cause and determine flows of materials and energy through the society. Sustainable development is associated to all the former issues, by encompassing them altogether under the same umbrella.Sustainable services are those, that restrain resource consumption and waste generation to an acceptable level, considering Earth's existing capital, rates of replenishment and carrying capacity, make a positive contribution to the satisfaction of human needs, and provide enduring economic value to the business enterprise. The selection of appropriate processes for providing a given sustainable service is the main topic of this thesis. This thesis presents a consistent framework for decision support towards sustainable design. It encompasses a set of methods and tools applicable to decision aid in process design, retrofit and operation considering sustainability criteria in terms of economic and environmental issues. In this sense special consideration is given to process simulation, general modelling programs and other multivariate statistical methods, as well as their supporting associated tools. The framework is materialised as a procedure for its application in four steps, which mimics other current applied methods; and a set of tools which are integrated. One of the framework aims is the consideration of the uncertainty associated to parameters and values. The tools, which in all cases are mathematical models, allow for an accurate representation of the reality they simulate. In the case of alternatives generation problem, the resultant multiobjective optimisation problem is solved by an strategy that permits narrowing-in the best solution compromise. A multitude of industrial case studies teaches the way to use the framework in different scenarios.The framework is applied to different case studies which require decision aid. The case of continuous process design is first addressed along with three different studies. The first one is related to the selection of waste water treatment options for a phosphoric acid plant considering uncertainty in operating variables, another analysis considers the decisions related to raw material management in an integrated gasification combined cycle power plant, while the last one addresses the design of a reactive distillation system considering optimisation of operating variables. All case studies are modelled rigorously using state of the art commercial simulation tools in conjunction with other tools developed for the assessment of sustainability concerns, mainly economic and environmental issues. The operational problem of selecting appropriate schedules, for the production of different products, is addressed next. In this case, special attention is given to the selection of appropriate metrics, considering economic, efficiency and environmental concerns that reflect the sequence dependence features of this problem. The model proposed is built using mathematical programming and the production of acrylic fibres is the application considered. Finally, the framework is applied to the design and retrofit of the whole chemical supply chain. Mid- to long-term planning decisions are modelled in this case, which studies a maleic anhydride production supply chain in Western Europe. Due to the problem nature, economic-environmental instruments such as emission trading and price subsidies are studied showing the viability of the presented approach for policy analysis.The case studies and the proposed framework show that different trade offs appear at different decision making levels. Moreover, the framework provides with a robust approach for traceability and verifiability of different modelling hypothesis which strengthens the decision making process.

En la presente tesis doctoral, se desarrolla y se valida una metodología de planificación de la red de distribución de cadenas de suministro de la industria de consumo masivo de alimentos envasados, que se ha estructurado tomando como base los conceptos lean y agile, desarrollados por diferentes autores en los últimos veinte años. Se define, también, las ventajas y limitaciones al aplicar esta metodología y compararla con la metodología de planificación tradicional, a fin de determinar si da mayor valor al cliente de este tipo de industria. El tema concluye con la validación de tres hipótesis, que validan la aplicabilidad de la metodología desarrollada y de los conceptos lean y agile en la industria de alimentos envasados, con ciertas limitantes establecidas en el desarrollo de la investigación. / The doctoral thesis, develop and validates a distribution net planning methodology of packaged foods consumer goods supply chain, that has been structured taking as it base the lean and agile concepts, developed by differents authors in the last twenty years. Also, it defines the advantages and limitations when applying this methodology and compare it with the traditional planning methodology, to end determine if it gives main value to the client of this type of industry. The thesis concludes with the validation of three hypotheses that validate the applicability of the methodology developed and of the concepts.

Supply chain management has experienced great changes within the last fifty years. Inevitably, many companies entered the global market with the prime intention to achieve their defined goals. In comparison with the local markets, the global environment requires more efforts and changes in the supply chain operation in order to remain viable in business. Several business models are introduced for achieving the success in the market, suggested by the following researchers: Liker, Choi, Ronald Gilson, andMark J. Roeand others.  In a row with the study cases of Honda and Toyota Companies, the Supply Chain Trading Security is presented. Within this paper the security approaches are discussed during the processes of market penetration and development globally. The main strengths and weaknesses of the models are highlighted in the thesis. The description of market situations and explanation of the models’ application is presented. In order to achieve better results in the analysis of the case studies, the qualitative and inductive research methods have been implemented. The secondary data is considered to be the cornerstone of the thesis. Due to the fact that the thesis is based on descriptive, partially explanatory, and qualitative research methods, different meanings and experiences related to the Supply Chain Security phenomenon are discussed. In order to obtain the necessary data, library catalogues, encyclopedias, databases, and search engines in the Internet are utilized. The thesis goes through the following processes: choice of research area, formulation of research questions, choice of method, formulation of research design and data collection techniques, implementation of data collection, analysis of data, interpretation of data, and finally conclusions. The studied companies in the thesis – Toyota and Honda – conducted four major supply chain models that are neatly explained through the research. Partnership, Supplier Keiretsu, ARA, and Triple-A are the operated models. The following issues have been derived as conclusions: many components of supply chain security in terms of trade, affect the whole organization to a great extent. In order to keep the customer loyalty, image, and brand, companies should focus on their own core competence. Complex, transnational, and multi-vendor supply chain security models require more collaboration on safety issues that is approximately a half of the whole job. In addition, management and control of activities are necessary in order to achieve the target, go through the obstacles, and manage the current market situation.  Economic, political, and nature influence are key determinants of the supply network situation and give the possibility for a company to gain benefits, and control all business activities. The optimal choice of the model is considered to be the main tool aiming to manage all aforementioned tasks. Furthermore, diverse cultural differences influence the choice of the models that are implemented by the American and Japanese companies.

This thesis studies three problems related to inventory control. The first problem is motivated by the need to eliminate the bullwhip effect in a supply chain. An important source of this effect is the inventory control policy, which is originally designed to smooth production in response to demand variation along the supply chain arising from the customers. To address this issue, we propose an estimation method based on the control variate technique. A byproduct of this approach is a stabilizing inventory control policy. We evaluate the effectiveness of the proposed method using the models from the literature. Generally, the derivation of the inventory policies requires the knowledge of the specific demand distribution. Unfortunately, in several cases the demand is not observable in a direct way. The second problem is motivated by a practical application where only partial demand information is observable. Towards this end we derive estimators of the first two moments of the (daily) demand by means of the renewal theoretical concepts. We also propose a regression-based approximation to improve the quality of the estimators. A series of numerical studies are carried out to evaluate the accuracy and precision of the estimators and to investigate the impact of the estimation on the optimality of the inventory policies. The last part of this dissertation studies a periodic-review inventory system with regular and emergency orders. Emergency orders, characterized by shorter lead-time, higher ordering cost and higher setup cost, are placed when the inventory level becomes critically low. Based on our assumptions, we formulate a dynamic programming model and prove the optimality of state-dependent sS type polices for both emergency and regular orders. We also derive analytic properties of the optimal policies. We gain some managerial insights into the optimal policies and cost performance from numerical studies.

This Record of Study contains the details of an optimization model developed for Shell Oil Co. This model will be used during the strategic design process of a supply chain for a new technology commercialization. Unlike traditional supply chain deterministic optimization, this model incorporates different levels of uncertainty at suppliers’ nominal capacity. Because of the presence of uncertainty at the supply stage, the objective of this model is to define the best diversification and safety stock level allocated to each supplier, which minimize the total expected supply chain cost. We propose a Monte Carlo approach for scenario generation, a two-stage non-linear formulation and the Sample Average Approximation (SAA) procedure to solve the problem near optimality. We also propose a simple heuristic procedure to avoid the nonlinearity issue. The sampling and heuristic optimization procedures were implemented in a spreadsheet with a user’s interface. The main result of this development is the analysis of the impact of diversification in strategic sourcing decisions, in the presence of stochastic supply disruptions.

Recently, the meat supply chain has undergone a number of structural changes including increased concentration and a greater degree of quasi-vertical integration coordinated through contract procurement. The effects these changes have had on the meat supply chain, arranged as a complex array of producers, processors, distributors, and retailers, are not yet known. This study investigates the motives for, and consequences of, recent changes in the meat supply chain. The first essay examines causality among variables in the U.S. cattle supply chain using temporal and contemporaneous causality methodologies. Tests for structural changes reveal a likely structural change between later 1996 and early 1997 that was likely induced by the turnaround of the U.S. cattle inventory accompanied with severe droughts in Midwest. Results suggest that overall temporal causalities in the U.S. cattle supply chain become weaker after the structural change, though relatively strong causalities are found in pre-break periods. In contrast, strong contemporaneous causal relationships are founded in post-break periods. One conclusion is that recent structural changes in the industry are resulting in more rapid transmission of information through the supply chain. Causal evidence also suggests that the direction of information transmission has changed in recent times from moving generally downstream to moving generally upstream. This might be the result of increased concentration at the packer and retail levels giving rise to increased ability to “set” prices. The second essay develops a theoretical model to investigate the dynamic effects of the contract procurement on packer competition in the spot market with general contract pricing scheme. Results indicate that packers have an incentive to consider the effects of spot market purchases on contract procurement even after accounting for hedonic characteristics of live cattle and risk aversion in cattle feeding operations. The third essay investigates the impacts of domestic and overseas animal disease outbreaks on the Korean meat supply chain. Market impacts are investigated using both forecasts and historical decomposition of price innovations based on an error correction model (ECM) of the Korean meat sector. Results indicate that while the affected markets suffered significantly from the outbreaks, the impacts seem temporary and substitute meat markets benefited significantly.

Agricultural supply represents the quantity supplied for a given price of a commodity. The supply function is an algebraic representation that shows, in this case, how much yield and acreage output changes from variations in prices and various inputs. Estimating supply functions is an important economic research topic. However, publications on this topic involving applications to agricultural crops are not plentiful, particularly for cotton. This paper focuses on the estimation of cotton supply functions and elasticities within the United States cotton industry. U.S. cotton yields appear to have been dramatically increased in recent years from newer varieties, boll weevil eradication, weather, and other technological improvements. Changes in both productivity and input cost suggest likely changes in supply relationships. Seventeen cotton producing states were divided into homogenous regions. A two equation model was used to estimate the supply functions and elasticities for each region. The results were mixed, depending on the region. There was difficulty in finding good model fits likely due to complexities of biological responses as well as policy distortions. The parameter results suggest that the major determinates of yield were weather and technology. The major determinates of estimating acreage was production in the previous year and policy variables. The overall purpose of this paper was to estimate cotton supply elasticities, which tended to be inelastic across the United States.

Because of the exceptional physical, chemical, electric and mechanical properties of hard and brittle materials, such as ceramics, glass and diamond film etc, those are considerably valued in high technology industry. Although those materials can be machined using the ECDM method, but mostly used for machining hole and wire cutting, there is few application in the polishing aspect. In this study, a high-precision dynamic electrical pitting tester is employed, the electrolyte is KOH(eq), investigate the behavior of static electrochemical discharge of supply voltage and electrolyte highly to the steel ball/glass, and analysis it¡¦s machining characteristic. From the experimental results, which are SEM pictures of machined glass and variations of current and force , we can clearly infer the electrochemical discharge machining mold, and establish electrochemical I-V curve under different electrolyte highly, and furthermore machining area classify for (1) non-machining district (2) precision machining district (3) middle machining district (4) heavy machining district. The experimental results shows, the pitting of damage width and depth and supply voltage are relation in direct ratio. Under three different electrolytes highly, shows the critical voltage of pitting damage are all the same value, namely 29V, and electrolyte highly will be influenced real machining time and damaged form of surface. In the precision machining district, can get the surface roughness (Ra) reach 0.02£gm, machining depth of surface damage reach 0.3649£gm after machined for 60 seconds under the optimum operating parameter.

The Planning of Supply Chain Management System for Industrial Materials Intermediary

This Record of Study contains the details of an optimization model developed for Shell Oil Co. This model will be used during the strategic design process of a supply chain for a new technology commercialization. Unlike traditional supply chain deterministic optimization, this model incorporates different levels of uncertainty at suppliers' nominal capacity. Because of the presence of uncertainty at the supply stage, the objective of this model is to define the best diversification and safety stock level allocated to each supplier, which minimize the total expected supply chain cost. We propose a Monte Carlo approach for scenario generation, a two-stage non-linear formulation and the Sample Average Approximation (SAA) procedure to solve the problem near optimality. We also propose a simple heuristic procedure to avoid the nonlinearity issue. The sampling and heuristic optimization procedures were implemented in a spreadsheet with a user's interface. The main result of this development is the analysis of the impact of diversification in strategic sourcing decisions, in the presence of stochastic supply disruptions.