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Návrh řízení dopravníkové techniky řešící dodržení pořadí zakázek při průchodu výrobní oblastí pomocí diskrétní simulace / Design of conveyor systems to address compliance with the sequence of orders passing through production areas using discrete event simulationČtveráček, Martin January 2014 (has links)
This thesis is focused on using discrete event simulation in a large plant in order to improve the control logic of the production department. Specifically it’s about the factory ŠKODA AUTO a.s. located in Mladá Boleslav and solved production node is the paint shop area. The chapters of this thesis are focused on used conveyor technology, basics of discrete event simulation, the subsequent development of a virtual model, design of simulation experiments and concept of a new solution. At the end of this work evaluation of proposed solution with comparison to the original solution is included.
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Analýza a zvýšení výkonu elektronického obchodu využitím digitálních nástrojů / Analysis and Performance Increase of e-Commerce Shop Through Digital ToolsChalupa, Patrik Unknown Date (has links)
This thesis deals with digital tools that are used in the performance marketing concepts. At the outset characterizes an Internet marketing and provides various forms of advertising on the Internet. The practical part is devoted to analysis of Internet business Planetaher.cz, which is based on an online marketing strategy designed to increase the volume of visits and sales in the e-shop. The practical part is focused on the scoring method of risk management in project management. At the conclusion suggests a few recommendations, which hold for further streamlining the entire Internet business.
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Podnikatelský plán založení internetového obchodu se sportovní výživou a cvičebními pomůckami / The Business Plan for Establishment Online Store in the Sale of Sports Nutrition and Exercise EquipmentHavránek, Martin January 2016 (has links)
The main goal of this thesis is design plan for e-shop focused on sport supplements and equipment. Main parts of this labor, which will be used as basis for design of business plan, are selected analysis of environment for setting up demand and circumstances connected with them. Following step will be to chart competitive environment of segment of market, for this step we will use data from main research. This research discovering targeted customer´s preferences. Suggestions mentioned in this thesis will be use as support for realization of this business plan.
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Flowshop-Probleme mit Puffern: Analyse und Entwurf eines AmeisenalgorithmusWinkel, Martin 21 November 2017 (has links)
The aim of this thesis is to design and evaluate an ant algorithm for a certain class of (hybrid) flowshop problems.
These problems consist of a two-staged production process with two identical machines on the second station and buffers in between the stages. For a given number of jobs, each consisting of a processing time and a deadline, the goal is to create a feasible partition and permutation of these jobs which minimizes the total tardiness. Furthermore, a theoretical investigation on the placement and size of the buffers and its impact on the resulting solution space was done.
In order to further improve the swarm intelligence it was combined with a set of different heuristics and pheromone evaluation rules. The resulting variations of the algorithm were later tested and evaluated on a set of benchmark instances. Subsequently, the obtained theoretical insights on the flowshop problems were analyzed in a practical matter and proved to be valuable. Finally, the quality of the solutions found by the designed ant algorithm was analyzed on smaller pro- blem instances. It became apparent that at least for such smaller problems the algorithm creates very good solutions which only differ little from the optimum.
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Makespan Minimization in Re-entrant Permutation Flow ShopsHinze, Richard 29 August 2017 (has links)
Re-entrant permutation flow shop problems occur in practical applications such as wafer manufacturing, paint shops, mold and die processes and textile industry. A re-entrant material flow means that the production jobs need to visit at least one working station multiple times. A comprehensive review gives an overview of the literature on re-entrant scheduling. The influence of missing operations received just little attention so far and splitting the jobs into sublots was not examined in re-entrant permutation flow shops before. The computational complexity of makespan minimization in re-entrant permutation flow shop problems requires heuristic solution approaches for large problem sizes. The problem provides promising structural properties for the application of a variable neighborhood search because of the repeated processing of jobs on several machines. Furthermore the different characteristics of lot streaming and their impact on the makespan of a schedule are examined in this thesis and the heuristic solution methods are adjusted to manage the problem’s extension.
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Mockumentärfilm: : StilelementEkberg, Sean January 2020 (has links)
Uppsatsen är gjord i form av en stilistisk analys med mål att utforska dokumentärfilmens autenticitet och mer specifikt en analys av mockumentärfilmers stilelement. Tanken är att genom att analysera vilka stilelement som används i mockumentärfilmer och analysera hur filmskaparna använder dem inom en film skapad ur fiktion, att se ut som en dokumentärfilms form av autenticitet. För analysen valde jag ut tre mockumentärfilmer: This Is Spinal Tap (1984), Man Bites Dog (1992) och Exit Through The Gift Shop (2010). Dessutom valdes ytterligare nio dokumentärfilmer ut, som används i analysens del för att kunna ge exempel från mockumentär till dokumentär. Analysen visar att filmskapare av mockumentärfilmer och dokumentärfilmer använder samma stilelement, men skillnaden ligger i hur filmskaparna använder dem. En mockumentärfilmskapare använder dokumentära stilelement med avsikt att filmen ska få samma utseende som en dokumentärfilm. Analysen visar också att en stor skillnad mellan dokumentärfilmen och mockumentärfilmen finns inom kontraktet till tittaren. Mockumentärfilmskapare knyter ett kontrakt till tittaren för att få åskådaren att förstå att filmen är fiktion. Med hjälp av detta kontrakt och samma förståelse av filmens mockumentära innehåll ger detta åskådaren det fulla spektrumet av filmens innehåll.
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Entwicklung und Umsetzung eines Kennzahlensystems zur Leistungsmessung im KarosseriebauRichter, André 31 March 2009 (has links)
Der steigende Effizienzdruck in der Automobilindustrie führt zu der Notwendigkeit bereits in der frühen Planungsphase umfassende Aussagen in Bezug auf die Leistungsfähigkeit des entworfenen Systems zu machen. In der vorliegenden Arbeit wird für den Fertigungsbereich Karosseriebau ein Kennzahlensystem entwickelt, das eine fundierte Entscheidungsbasis für das Management bietet und den Fertigungsplaner mit detaillierten Informationen zur Erkennung von Schwachstellen versorgt. Zur Beherrschung des komplexen Gesamtsystems wird zunächst ein hierarchisches Prozessmodell erarbeitet, anhand dessen die wesentlichen Erfolgsfaktoren des Karosseriebaus identifiziert und parametriert werden. Die Kennzahlen werden definiert und entsprechend ihrer Ursache-Wirkungs-Beziehungen in einem durchgängigen, modularen Kennzahlensystem angeordnet. Zur Sicherung der Praxistauglichkeit werden bei der Entwicklung des Kennzahlensystems der Kennzahlenbedarf und die Kennzahlenverfügbarkeit über den Projektverlauf berücksichtigt. Die Berechnung und Komprimierung der Kennzahlen sowie die Visualisierung der Leistungsentwicklung werden in die Digitale Fabrik integriert und so der manuelle Pflegeaufwand reduziert. Der Nutzen des Kennzahlensystems in der Unternehmerischen Praxis wird anhand von Beispielen verdeutlicht und nachgewiesen.
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Optimal and heuristic solutions for the single and multiple batch flow shop lot streaming problems with equal sublotsKalir, Adar A. 06 March 1999 (has links)
This research is concerned with the development of efficient solutions to various problems that arise in the flow-shop environments which utilize lot-streaming. Lot streaming is a commonly used process of splitting production lots into sublots and, then, of scheduling the sublots in an overlapping fashion on the machines, so as to expedite the progress of orders in production and to improve the overall performance of the production system.
The different lot-streaming problems that arise in various flow-shop environments have been divided into two categories, single-lot problems and multiple-lot problems. Further classification of the multiple-lot problems into the lot streaming sequencing problem (LSSP) and the flow-shop lot-streaming (FSLS) problem is made in this work. This classification is motivated by the occurrence of these problems in the industry. Several variants of these problems are addressed in this research. In agreement with numerous practical applications, we assume sublots of equal sizes. It turns out that this restriction paves the way to the relaxation of several typical limitations of current lot-streaming models, such as assumption of negligible transfer and setup times or consideration of only the makespan criterion. For the single-lot problem, a goal programming (GP) approach is utilized to solve the problem for a unified cost objective function comprising of the makespan, the mean flow time, the average work-in-process (WIP), and the setup and handling related costs. A very fast optimal solution algorithm is proposed for finding the optimal number of sublots (and, consequently, the sublot size) for this unified cost objective function in a general m-machine flow shop.
For the more complicated multiple-lot problem, a near-optimal heuristic for the solution of the LSSP is developed. This proposed heuristic procedure, referred to as the Bottleneck Minimal Idleness (BMI) heuristic, identifies and employs certain properties of the problem that are irregular in traditional flow-shop problems, particularly the fact that the sublot sizes eminating from the same lot type and their processing times (on the same machines) are identical. The BMI heuristic attempts to maximize the time buffer prior to the bottleneck machine, thereby minimizing potential bottleneck idleness, while also looking-ahead to sequence the lots with large remaining process time earlier in the schedule. A detailed experimental study is performed to show that the BMI heuristic outperforms the Fast Insertion Heuristic (the best known heuristic for flow-shop scheduling), when modified for Lot Streaming (FIHLS) and applied to the problem on hand.
For the FSLS problem, several algorithms are developed. For the two-machine FSLS problem with an identical sublot-size for all the lots, an optimal pseudo-polynomial solution algorithm is proposed. For all practical purposes (i.e., even for very large lot sizes), this algorithm is very fast. For the case in which the sublot-sizes are lot-based, optimal and heuristic procedures are developed. The heuristic procedure is developed to reduce the complexity of the optimal solution algorithm. It consists of a construction phase and an improvement phase. In the construction phase, it attempts to find a near-optimal sequence for the lots and then, in the improvement phase, given the sequence, it attempts to optimize the lot-based sublot-sizes of each of the lots. Extensions of the solution procedures are proposed for the general m-machine FSLS problem.
A comprehensive simulation study of a flow shop system under lot streaming is conducted to support the validity of the results and to demonstrate the effectiveness of the heuristic procedures. This study clearly indicates that, even in dynamic practical situations, the BMI rule, which is based on the proposed BMI heuristic, outperforms existing WIP rules, commonly used in industry, in scheduling a flow-shop that utilizes lot streaming. With respect to the primary performance measure - cycle time (or MFT) - the BMI rule demonstrates a clear improvement over other WIP rules. It is further shown that it also outperforms other WIP rules with respect to the output variability measure, another important measure in flow-shop systems. The effects of several other factors, namely system randomness, system loading, and bottleneck-related (location and number), in a flow-shop under lot streaming, are also reported. / Ph. D.
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Entwicklung und Validierung eines Fragebogens zur Evaluation der Gebrauchstauglichkeit von Online-Shops / Development and Validation of a Questionnaire for the Evaluation of Online-Shop UsabilityOllermann, Frank 28 October 2008 (has links)
In der vorliegenden Arbeit wird ein Fragebogen zur Evaluation der Gebrauchstauglichkeit von Online-Shops entwickelt und Hinweise auf seine Reliabilität und Validität erbracht. Damit leistet die Arbeit einen Beitrag zur Verbesserung der Gebrauchstauglichkeit von Online-Shops zum Vorteil von Kunden und Anbietern. Gebrauchstauglichkeit ist ein komplexes Konstrukt, das sich vor allem durch seine Abhängigkeit von Produkt- und Benutzereigenschaften sowie von Eigenschaften des Nutzungskontexts und den Nutzungszielen der Benutzer auszeichnet. Eine Evaluation der Gebrauchstauglichkeit eines Online-Shops kann somit grundsätzlich nicht sinnvoll erfolgen. Vielmehr müssen bei der Evaluation die genannten Randbedingungen der Benutzung berücksichtigt werden. Zur Evaluation der Gebrauchstauglichkeit stehen verschiedene Methoden zur Verfügung. Sie lassen sich danach unterscheiden, ob sie prädiktiv oder deskriptiv, verhaltensbasiert oder meinungsbasiert sind und ob ihnen objektive oder subjektive Kriterien zugrunde liegen. Daraus ergeben sich für die verschiedenen Methoden unterschiedliche Anwendungsszenarien. Die Fragebogenmethode wird als geeignete Evaluationsmethode identifiziert, weil sie eine subjektive, benutzerbasierte Messung der Gebrauchstauglichkeit erlaubt, was bei der Evaluation speziell von Online-Shops, deren Benutzung in der Regel freiwillig erfolgt, zu aussagekräftigen Ergebnissen führt. Nach der aufwendigen und sorgfältigen Entwicklung des Fragebogens wird dieser auf seine Validität hin überprüft. Dabei wird eine weitgehende Gültigkeit des Fragebogens festgestellt. So stimmt die durch eine benutzerzentrierte Evaluation dreier Online-Shops mit dem Fragebogen erzeugte Rangreihe weitgehend mit der überein, die sich aus einem Expertenrating ergibt. Außerdem ist der Fragebogen sensitiv für Unterschiede zwischen Online-Shops, die sich hinsichtlich ihrer ergonomischen Gestaltung bezüglich einer spezifischen Kaufphase (Produktsuche) unterscheiden.
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Job-shop scheduling with limited buffer capacitiesHeitmann, Silvia 18 July 2007 (has links)
In this work, we investigate job-shop problems where limited capacity buffers to store jobs in non-processing periods are present. In such a problem setting, after finishing processing on a machine, a job either directly has to be processed on the following machine or it has to be stored in a prespecified buffer. If the buffer is completely occupied the job may wait on its current machine but blocks this machine for other jobs. Besides a general buffer model,also specific configurations are considered.The key issue to develop fast heuristics for the job-shop problem with buffers is to find a compact representation of solutions. In contrast to the classical job-shop problem,where a solution may be given by the sequences of the jobs on the machines, now also the buffers have to be incorporated in the solution representation. In this work, we propose two solution representations for the job-shop problem with buffers. Furthermore, we investigate whether the given solution representations can be simplified for specific buffer configurations. For the general buffer configuration it is shown that an incorporation of the buffers in the solution representation is necessary, whereas for specific buffer configurations possible simplifications are presented. Based on the given solution representations we develop local search heuristics in the second part of this work. Therefore, the well-known block approach for the classical job-shop problem is generalized to the job-shop problem with specific buffer configurations.
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