Ce travail présente l'étude de deux types de problèmes d'ordonnancement. Le premier concerne la résolution centralisée et exacte d'un problème à une machine, le second, la résolution distribuée et coopérative d'un problème job shop où chaque machine est assimilée à un acteur possédant sa propre autonomie décisionnelle. Pour ces deux problèmes, des conditions de dominance sont utilisées, dans le premier cas, dans le but de limiter la complexité algorithmique liée à la recherche de solutions admissibles ou optimales, dans le deuxième cas, pour accroître la capacité de chaque acteur à résister aux incertitudes liées aux fluctuations de son environnement. Dans un premier temps, un théorème proposé dans les années quatre-vingt est rappelé, qui, considérant le problème à une machine, permet de caractériser un ensemble de solutions dominantes. Sur la base de ce théorème, nous proposons ensuite de nouvelles conditions analytiques et numériques de dominance permettant de restreindre encore davantage l'ensemble des solutions dominantes. En exploitant ces résultats, des formulations mathématiques originales et efficaces sont présentées, sous forme de programmes linéaires en nombres entiers, pour la modélisation et la résolution du problème à une machine en s'intéressant tour à tour au critère de minimisation du plus grand retard algébrique, puis à celui de minimisation du nombre de travaux en retard. Dans un deuxième temps, nous étudions le problème d'ordonnancement job shop dans un environnement multi-acteur, chaque acteur gérant l'activité d'une machine. Tenant compte de l'autonomie de décision et des objectifs propres de chacun, l'ordonnancement est envisagé sous la forme d'une fonction distribuée où la solution globale résulte d'une coopération entre les différents acteurs, cette solution pouvant évoluer dans le temps au fur-et-à-mesure des prises de décision locales. Ainsi, chaque acteur construisant localement sa propre organisation et n' n'ayant qu'une connaissance part ielle et incertaine de l'organisation des autres, nous proposons que les organisations locales soient construites de façon robuste. Pour cela nous montrons comment, à l'aide des résultats de dominance, maintenir au niveau de chaque acteur un ensemble dominant de solutions ayant une performance au pire bornée. Une nouvelle approche d'ordonnancement est ensuite proposée où les acteurs négocient deux à deux, de façon distribuée, de façon à converger progressivement vers des décisions assurant un compromis satisfaisant entre l'optimisation des objectifs locaux et des objectifs globaux.

In this thesis, the Job Shop Scheduling Problem (JSSP) is the problem of interest. The classical JSSP is well-known as an NP-hard problem. Although with current computational capabilities, the small problems are solvable using deterministic methods, it is out of reach when they are larger in size. The complexity of JSSP is further increased when process interruptions, such as machine breakdown and/or machine unavailability, are introduced. Over the last few decades, several stochastic algorithms have been proposed to solve JSSPs. However, none of them are suitable for all kinds of problems. Genetic and Memetic algorithms have proved their effectiveness in these regards, because of their diverse searching behavior. In this thesis, we have developed one genetic algorithm and three different Memetic Algorithms (MAs) for solving JSSPs. Three priority rules are designed, namely partial re-ordering, gap reduction and restricted swapping, and these have been used as local search techniques in designing our MAs. We have solved 40 well-known benchmark problems and compared the results obtained with some of the established algorithms available in the literature. Our algorithm clearly outperforms those established algorithms. For better justification of the superiority of MAs over GA, we have performed statistical significance testing (Student's t-test). The experimental results show that MA, as compared to GA, not only significantly improves the quality of solutions, but also reduces the overall computation. We have extended our work by proposing an improved local search technique, shifted gap-reduction (SGR), which improves the performance of MAs when tested with the relatively difficult test problems. We have also modified the new algorithm to accommodate JSSPs with machine unavailability and also developed a new reactive scheduling technique to re-optimize the schedule after machine breakdowns. We have considered two scenarios of machine unavailability. Firstly, where the unavailability information is available in advance (predictive), and secondly, where the information is known after a real breakdown (reactive). We show that the revised schedule is mostly able to recover if the interruptions occur during the early stages of the schedules. We also confirm that the effect of a single continuous breakdown has more impact compared to short multiple breakdowns, even if the total durations of the breakdowns are the same. Finally, for convenience of implementation, we have developed a decision support system (DSS). In the DSS, we have built a graphical user interface (GUI) for user friendly data inputs, model choices, and output generation. This DSS tool will help users in solving JSSPs without understanding the complexity of the problem and solution approaches, as well as will contribute in reducing the computational and operational costs.

Univ., Diss.--Gießen, 2003. / Literaturverz. S. 283 - 307.

This diploma thesis analyses the specialized internet shop (e-shop), it's technical and business preparation, it's market entrance, first marketing activities, corrections and valuates it's economical situation.

Denna rapport vill belysa kunders problem med att hitta passande storlek när de handlar kläder i en webbutik. Fokusområdet är att undersöka om det är möjligt för kunder att ta tillförlitliga kroppsmått eller plaggmått med måttband, för att välja passande klädstorlek vid e-handel.   Först genomfördes en marknadsundersökning för att ta reda på hur klädföretag utformar sina storleksguider. Därefter utfördes en undersökning där 20 militärer deltog. De fick i uppgift att följa instruktioner för att ta kroppsmått på sig själva, ta samma mått på varandra och måtta av två utvalda plagg. Avslutningsvis fick de låta sig bli mätta av en designtekniker. Resultatet visade mycket stor spridning och flera av måtten hade ett spann från -6 cm till +6 cm i jämfört med att en professionell genomförde mätningen. En upptäckt var att vissa mätresultat blev bättre när någon annan än personen själv utförde kroppsmätningen. Deltagarna fick som avslut svara på några frågor. Hela 60 % av deltagarna i testgruppen trodde att en filminstruktion skulle ha underlättat mätningen. Slutsatsen är att det är viktigt att informera kunder hur de bör ta hjälp med att ta sina mått i användandet av storleksguiden, och att en instruktionsfilm kan underlätta mätningen. Ett komplement till kroppsmått kan vara plaggmått i storleksguiden. / The purpose of this report is to highlight customers' problems in finding the right size when shopping for clothes in an online store. The focus area is to investigate whether it is possible for customers to take accurate body measurements or garment measurements with a measuring tape in order to select appropriate clothing size in e-commerce.   A market investigation on the internet was conducted to find out how clothing companies design their size guides. Then a study took place with 20 participant soldiers. They were asked to follow the instructions for taking body measurements of themselves, to take measurements of each other and to measure two selected garments. Finally, they where measured by a garment technologist. The result showed a very large difference, and several of the measures had a span from -6 cm to +6 cm. One finding was that some measurement results were improved when someone else than themselves performed the body measuring. Afterwards the participants were asked to answer a few questions. Around 60 % of the them believed that a film instruction could facilitate the body measuring. The conclusion is that it is important to inform the customers in the size guide that it is important to get help to get as accurate measurements as possible and that an instructional film can facilitate the measuring. A complement to body measurements can be garments measurements in the size guide.

Made available in DSpace on 2010-04-20T20:15:29Z (GMT). No. of bitstreams: 0 Previous issue date: 1992-12-15T00:00:00Z / Analisa os programas de televisão que são, exclusivamente, para anunciar produtos e serviços. Para esse tipo de programa foi criada a denominação 'Shopping na TV' utiliza como estudo de caso o Shop Tour, um desses programas, exclusivo para anúncios de produtos e serviços a preços promocionais. Analisa esse novo estilo de propaganda sob o enfoque da teoria de marketing, abordando como referencial teórico: o processo de comunicação, a propaganda, a promoção de vendas e o comportamento do consumidor diante dessas formas de comunicação. Apresenta resultados da pesquisa de campo realizada com os anunciantes do Shop Tour.

Dissertation "The Origins of the Mass Consumption Society in Czechoslovakia 1945-1970. Trade, Consumption and Advertising" deals with the process of establishing consumption as a new category of human life in the communist dictatorship in Czechoslovakia. Through the analysis of the discourse the author shows how a network of specialized institutions and professionals producing thinking about consumption emerged in the milieu of the Ministry of Internal Trade. This network manifested itself in the planning of the trade infrastructure and in the adoption of a more subtle approach to the problem of consumption in an effort to maintain the legitimacy of the communist rule. The commerce as a sphere of economy was in the communist discourse initially reduced to the transmission lever between production and the consumer. This perception was accompanied by the pursuit of the social justice through the transformation of the consumer's experience, underpinned by a strong moral appeal. The key tools used in this process were the democratization of the access to the goods, the attempts to adapt the services to broad sections of the society, the chance given to the consumers to raise their own demands and also the "new language" of the trade practices. Political thaw after Stalin's death led to the...

This work studies factors of e-shops credibility on the field B2C. The aim of the work was to work out a summary of recommendations for businessmen, who deal with or consider internet marketing, and to introduce particular suggestions for a specific e-shop.

Magister Philosophiae - MPhil (LAS) (Land and Agrarian Studies) / Fish remains a vital source of food, income, nutrition and livelihoods for millions of people in Africa. This study investigated the modalities of trading in fish imported from sub-Saharan Africa into South Africa in the Cape Town Metropolitan area. The research analyses the opportunities and constraints faced by retail fish traders and importers regarding the South African and Southern African Development Community (SADC) policies that are in place, to ascertain how far the policies go in facilitating the intra-regional fish trade. In addition, the study analyses consumer factors underlying the attractiveness of imported fish, the channels used for importation as well as the types and forms of fish imported into South Africa. The study employs a qualitative approach using semi-structured interviews with purposively selected key informant retailers, traders and City of Cape Town officials to collect the information. Findings show that shop owners and traders face challenges in relation to obtaining the required documents for trading, sanitary and phytosanitary certification and tariff and non-tariff barriers at borders. Some of these challenges include long and tedious procedures to acquire documents, as well as the limitations placed on the amount of goods traders can import. Consumers (mostly from the diaspora) prefer the taste of fish that they are used to, thereby creating an increasing demand for imported fish. National and regional policies put in place do not facilitate the trade in fish as well as current municipal regulations for retailing imported fish and other food types. The study also raises critical questions about the implementation of sanitary and phytosanitary standards by officials in the food shops. The thesis concludes that is it critical for national and regional policies to be coordinated and harmonised for enhanced intra-regional fish trade, which could contribute towards increased food security, nutrition and livelihoods.

My diploma thesis is focused on creating an application for Electronic Register of Sales. The main sense of the application is to facilitate an implementation to e-shops, which were created on so-called "Greenfield". This application is supposed to help programmers in their work, because the most complex logic will be done by the app. Another big advantage of it is saving money to the e-shop owners. The implementation of my solution is more time saving than the implementation which is provided by Financial administration of the Czech Republic. The first part of my thesis is concentrated on Electronic Register of Sales issue. It's following by a description of technology and tools which I used for the app development. The selected technology and tools are the most modern and widely used nowadays. The end of the theoretical part is about introducing e-shop Tisknisi.cz In the practical part of the thesis I described the "E-EET" application and compiled its structure in terms of frontend and backend. Then I explained its technical solution. Code samples are accompanied by explanations. A phase "implementation solution" is described by POST request method. I've designed a price policy to ensure the profitability of "E-EET" application by myself.