Thesis (M. Sc.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 45-47).

Zugl.: Göttingen, Univ., Diss., 2009

Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 190-192). Also available on the Internet.

Med energieffektivisering menas att man använder energi på ett effektivt sätt som ska leda till en positiv inverkan på miljö och samhälle. Sisjö Entré är ett köpcentrum som har en årlig energiförbrukning på 1 865 270 kWh och bör enligt Energimyndighetens riktvärde ha en årlig förbrukning på 1 530 000 kWh, alltså en minskning med 18 %. Köpcentret består av 17 butiker och i examensarbetet undersöks fem butiker vilka är Toys Я Us, Rusta, Burger King, Babyproffsen och Webhallen. I dessa utförs mätningar på ventilation och belysning med syftet att studera vilka laster i butikerna som orsakar mest förbrukning. Målet är att komma fram till förslag på åtgärder för att minska energiförbrukning samt kostnader. Vi kom fram till att belysning är den största lasten i handelslokaler vilka är Toys Я Us, Rusta, Babyproffsen och Webhallen medan den största lasten i restauranger (Burger King) är utrustningen i köket som står för 75 % av restaurangens totala förbrukning. I Rusta upptäckte vi att elmätarna visade lägre värden än den verkliga förbrukningen. Efter undersökningen kom vi fram till att felet antingen ligger i elmätarna eller i dess strömtransformator och måste åtgärdas. Vi har gett förslag på att byta ut en del av den befintliga belysningen samt gett förslag på att sektionera vissa delar i några av butikerna. Dessutom har vi gett förslag på att reducera drifttiderna på ventilationsaggregaten. Utifrån dessa förslag och energiberäkningar kom vi fram till att man i de fem butikerna kan minska den årliga energiförbrukningen från 1 865 270 kWh till 1 576 670 kWh, alltså en minskning på 15,5 %. Därmed minskar kostnaderna med ca 228 000 sek/år / Energy efficiency means that energy is used in an efficient way that impacts positively on the environment and society. Sisjö Entré is a shopping center which has an annual energy consumption of 1 865 270 kWh, and according to Energy Authority, the recommended value is 1 530 000 kWh per year. That means that energy consumption at the center should reduce by approximately 18 % to comply with the recommended value. The mall consists of 17 stores and the thesis examines five stores which are Toys Я Us, Rusta, Burger King, Babyproffsen and Webhallen. Measurements are taken on ventilation and lighting installations with the aim of studying the loads in the stores that consume the most energy. The goal is to come up with suggestions of actions to reduce energy consumption and costs. We concluded that lighting consumes the most energy in the warehouses; Toys Я Us, Rusta, Babyproffsen and Webhallen, while the largest load in the restaurants (Burger King) is the kitchen, which accounts for 75 % of the restaurants total consumption. In Rusta, we discovered that the electricity meter showed a lower value than the true consumption. After investigation, we concluded that the fault could be either in the electricity meter or in its current transformer and must be addressed. We have given a proposal to replace parts of the existing lighting installations, and given suggestion for sectioning certain parts in some stores. Further, we have given suggestions for reducing operating times on the ventilation units. Based on the above proposals and energy calculations, we concluded that these five stores has the potential to reduce the annual energy consumption from 1 865 270 kWh to 1 576 670 kWh, leading to a reduction by 15.5 %. This reduces costs by about 228 000 SEK per year

Pour la résolution de problèmes d’ordonnancement d’ateliers de type flow-shop en industries pharmaceutiques et d’ateliers de type job-shop flexible, deux méthodes d’optimisation ont été développées : une méthode utilisant les algorithmes génétiques dotés d’un nouveau codage proposé et une méthode d’optimisation par essaim particulaire modifiée pour être exploitée dans le cas discret. Les critères retenus dans le cas de lignes de conditionnement considérées sont la minimisation des coûts de production ainsi que des coûts de non utilisation des machines pour les problèmes multi-objectifs relatifs aux industries pharmaceutiques et la minimisation du Makespan pour les problèmes mono-objectif des ateliers job-shop flexibles.Ces méthodes ont été appliquées à divers exemples d’ateliers de complexités distinctes pour illustrer leur mise en œuvre. L’étude comparative des résultats ainsi obtenus a montré que la méthode basée sur l’optimisation par essaim particulaire est plus efficace que celle des algorithmes génétiques, en termes de rapidité de la convergence et de l’approche de la solution optimale / For flexible job-shop and pharmaceutical flow-shop scheduling problems resolution, two optimization methods are considered: a genetic algorithm one using a new proposed coding and a particle swarm optimization one modified in order to be used in discrete cases.The criteria retained for the considered packaging lines in pharmaceutical industries multi-objective problems are production cost minimization and total stopping cost minimization. For the flexible job-shop scheduling problems treated, the criterion taken into account is Makespan minimization.These two methods have been applied to various work-shops with distinct complexities to show their efficiency.After comparison of these methods, the obtained results allowed us to notice the efficiency of the based particle swarm optimization method in terms of convergence and reaching optimal solution

abstract: A good production schedule in a semiconductor back-end facility is critical for the on time delivery of customer orders. Compared to the front-end process that is dominated by re-entrant product flows, the back-end process is linear and therefore more suitable for scheduling. However, the production scheduling of the back-end process is still very difficult due to the wide product mix, large number of parallel machines, product family related setups, machine-product qualification, and weekly demand consisting of thousands of lots. In this research, a novel mixed-integer-linear-programming (MILP) model is proposed for the batch production scheduling of a semiconductor back-end facility. In the MILP formulation, the manufacturing process is modeled as a flexible flow line with bottleneck stages, unrelated parallel machines, product family related sequence-independent setups, and product-machine qualification considerations. However, this MILP formulation is difficult to solve for real size problem instances. In a semiconductor back-end facility, production scheduling usually needs to be done every day while considering updated demand forecast for a medium term planning horizon. Due to the limitation on the solvable size of the MILP model, a deterministic scheduling system (DSS), consisting of an optimizer and a scheduler, is proposed to provide sub-optimal solutions in a short time for real size problem instances. The optimizer generates a tentative production plan. Then the scheduler sequences each lot on each individual machine according to the tentative production plan and scheduling rules. Customized factory rules and additional resource constraints are included in the DSS, such as preventive maintenance schedule, setup crew availability, and carrier limitations. Small problem instances are randomly generated to compare the performances of the MILP model and the deterministic scheduling system. Then experimental design is applied to understand the behavior of the DSS and identify the best configuration of the DSS under different demand scenarios. Product-machine qualification decisions have long-term and significant impact on production scheduling. A robust product-machine qualification matrix is critical for meeting demand when demand quantity or mix varies. In the second part of this research, a stochastic mixed integer programming model is proposed to balance the tradeoff between current machine qualification costs and future backorder costs with uncertain demand. The L-shaped method and acceleration techniques are proposed to solve the stochastic model. Computational results are provided to compare the performance of different solution methods. / Dissertation/Thesis / Ph.D. Industrial Engineering 2011

abstract: This research is motivated by a deterministic scheduling problem that is fairly common in manufacturing environments, where there are certain processes that call for a machine working on multiple jobs at the same time. An example of such an environment is wafer fabrication in the semiconductor industry where some stages can be modeled as batch processes. There has been significant work done in the past in the field of a single stage of parallel machines which process jobs in batches. The primary motivation behind this research is to extend the research done in this area to a two-stage flow-shop where jobs arrive with unequal ready times and belong to incompatible job families with the goal of minimizing total weighted tardiness. As a first step to propose solutions, a mixed integer mathematical model is developed which tackles the problem at hand. The problem is NP-hard and thus the developed mathematical program can only solve problem instances of smaller sizes in a reasonable amount of time. The next step is to build heuristics which can provide feasible solutions in polynomial time for larger problem instances. The basic nature of the heuristics proposed is time window decomposition, where jobs within a moving time frame are considered for batching each time a machine becomes available on either stage. The Apparent Tardiness Cost (ATC) rule is used to build batches, and is modified to calculate ATC indices on a batch as well as a job level. An improvisation to the above heuristic is proposed, where the heuristic is run iteratively, each time assigning start times of jobs on the second stage as due dates for the jobs on the first stage. The underlying logic behind the iterative approach is to improve the way due dates are estimated for the first stage based on assigned due dates for jobs in the second stage. An important study carried out as part of this research is to analyze the bottleneck stage in terms of its location and how it affects the performance measure. Extensive experimentation is carried out to test how the quality of the solution varies when input parameters are varied between high and low values. / Dissertation/Thesis / M.S. Industrial Engineering 2012

This thesis deals with the issue of paid search ads. Search ads are explained in the context of the development of the Internet and search engines, the functioning of search engines and advertising systems in the Czech environment. The aim of this thesis is a practical demonstration of the creation of classic and product campaigns. Campaigns are created for specific e-commerce in advertising systems Google AdWords and Sklik. Subsequently they are processed and it is compiled a set of generally applicable rules for the proper and efficient creation of search campaigns. To verify broader use results is used qualitative methods of expert interview with an expert in PPC.

The aim of this thesis is to characterize the current situation of the company Znovín Znojmo Inc. in the area of distribution and to propose any improvement in this area based on the survey and mystery shopping. The theoretical part defines the service and service quality. The following is the characteristic of the chosen company. The practical part contains macro environment, characteristic of the market in which the company operates and characteristic of the customers and the competitors. The practical part continues with the characteristic of the company from the view of marketing mix with the emphasis on the distribution. In the second half of the practical part is evaluation of the survey and the mystery shopping. The ending of the thesis is based on found weaknesses in the distribution of the company, such as a behavior of the dealer to the customer, and proposing of the possible solutions.

A logística de contêiner vem aumentando sua participação em volume de cargas transportadas, tornando-se a parcela mais significativa do tráfego de mercadorias. Com isso, o gerenciamento dos altos custos envolvidos com a aquisição, manutenção, manipulação e transporte desses contêineres tornam-se um problema relevante para as organizações. As alocações dos contêineres cheios e vazios são comumente vistos como dois sistemas distintos e estáticos e não de forma intregada e dinâmica. Há um número restrito de trabalhos na literatura desenvolvendo heurísticas integrando os sistemas, porém não foi encontrada uma formulação ótima para o problema. Logo, a questão para a dissertação é quão próximo estão os resultados das heurísticas encontradas na literatura, para o problema da alocação de contêineres, dos resultados ótimos. O presente trabalho apresenta uma formulação matemática para o problema de alocação dinâmica, e integrada, para contêineres cheios e vazios. A formulação foi testada com diversos cenários, objetivando saber o limite computacional das instâncias para a formulação. Como o problema é um problema NP-Hard, heurísticas são comumente apresentadas na literatura. Demonstra-se como podem ser realizadas comparações entre os resultados das heurísticas e os resultados ótimos e visam a constatação da importância de uma formulação ótima para comparações. / Containers' Logistics has increased their importance in the goods transportion and nowadays, has the most important share of them. With that in mind, the management of high costs of acquisition, maintenance, manipulation and transportation of them became a significant problem to organizations. The problem of empty container allocation and load container allocation are commonly treated as two distinct, and static, systems, which means without integration and not dynamically. Just a couple of examples could be found of the two systems dynamically integrated, and no optimal model was found. So, the question here is how close heuristics' results are from the optimal results. A mathematical formulation is presented to the problem concerned with the integration and the dynamics associated to it. The formulation was tested with several scenarios to determine the maximum size that could be tested with optimal results, in an acceptable computacional time. Since the problem is a NP-Hard problem, heuristics approach are commonly used. Here is demonstrated how could be compare optimal solutions of the formulation and solutions from heuristics, and aim to demonstrate the significance of the optimal formulation.