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Effizienzsteigerung durch Clustermanagement in der Automobilindustrie aus Transaktionskostensicht
(2014)
Cluster und deren Management sind seit den 1990er Jahren im Fokus von Wissenschaft und Politik und werden als Instrument für globale Wettbewerbsfähigkeit genutzt. Die Europäische Kommission stellt dazu fest: "What is abundantly clear is that the stimulation of networking, including in the clusters […] is crucial and requires attention from policy makers". Um das Instrument Cluster gewinnbringend zu nutzen, ist es notwendig zu wissen, wie ein erfolgreiches Clustermanagement abläuft und gestaltet werden kann. Ziel der vorliegenden Arbeit ist es, diese Themenstellung anhand der deutschen Automobilindustrie zu untersuchen. Die deutsche Automobilindustrie ist für dieses Vorhaben von großem Interesse, da sie sowohl aus gewachsenen, als auch aus politisch initiierten Clustern besteht. Theoretischer Bezugsrahmen für die Arbeit ist die Transaktionskostentheorie, die eine Struktur zur Messung der Vorteilhaftigkeit einer Organisationsform vorgibt. Nach der Ausarbeitung der konzeptionellen Grundlagen der Clusterbildung wird über eine empirische Erhebung die Forschungsfrage erörtert: Welche Effizienzgewinne innerhalb der verschiedenen Transaktionskostenarten lassen sich in der deutschen Automobilindustrie durch Clustermanagement erzielen, das durch Unternehmen oder politische Instanzen initiiert wird? Die Untersuchung zeigt, dass die Unternehmen hier in der Verantwortung sind, konkret ihre Interessen zu formulieren und an ausgewählten Aktivitäten im Cluster teilzunehmen, um einen Vorteil zu generieren. Die opportunistische Teilnahme an einem angebotenen Programm zeigt nicht die gewünschte Effizienzsteigerung.
Multimedia retrieval is an essential part of today's world. This situation is observable in industrial domains, e.g., medical imaging, as well as in the private sector, visible by activities in manifold Social Media platforms. This trend led to the creation of a huge environment of multimedia information retrieval services offering multimedia resources for almost any user requests. Indeed, the encompassed data is in general retrievable by (proprietary) APIs and query languages, but unfortunately a unified access is not given due to arising interoperability issues between those services. In this regard, this thesis focuses on two application scenarios, namely a medical retrieval system supporting a radiologist's workflow, as well as an interoperable image retrieval service interconnecting diverse data silos. The scientific contribution of this dissertation is split in three different parts: the first part of this thesis improves the metadata interoperability issue. Here, major contributions to a community-driven, international standardization have been proposed leading to the specification of an API and ontology to enable a unified annotation and retrieval of media resources. The second part issues a metasearch engine especially designed for unified retrieval in distributed and heterogeneous multimedia retrieval environments. This metasearch engine is capable of being operated in a federated as well as autonomous manner inside the aforementioned application scenarios. The remaining third part ensures an efficient retrieval due to the integration of optimization techniques for multimedia retrieval in the overall query execution process of the metasearch engine.
Bitte beachten Sie, dass diese Publikation inzwischen erweitert und überarbeitet wurde. Sie finden die aktuelle Fassung unter folgendem Link:
https://ojs3.uni-passau.de/index.php/paradigma/issue/view/21
In diesem Papier werden für die Schulpraktika im Lehramtsstudium, für das Referendariat und schließlich für die professionelle Lehrkraft Handlungsstandards in sechs zentralen Dimensionen dargestellt: 1) Handeln als Lehrperson 2) die Schule als Lern- und Lebensraum 3) Unterrichtsbeobachtung und –evaluation 4) Unterrichtsplanung, -durchführung und –analyse 5) Klassenführung 6) Leistungsmessung In einer spiralcurricularen Darstellung wird der Weg der professionellen Entwicklung, beginnend bei den ersten Handlungserfahrungen als Lehrperson, anhand von Regelstandards entwickelt. Dazu werden jeweils Indikatoren aufgeführt, an denen man die Erreichung des jeweiligen Standards beobachten kann. Ein theoretischer Teil führt in die erziehungswissenschaftliche Diskussion rund um das Thema Lehrerbildungsstandards ein und verankert die vorliegenden sowie die dazugehörigen Indikatoren in der aktuellen Unterrichtsqualitätsforschung.
UME is the notion that a user should receive informative adapted content anytime and anywhere. Personalization of videos, which adapts their content according to user preferences, is a vital aspect of achieving the UME vision. User preferences can be translated into several types of constraints that must be considered by the adaptation process, including semantic constraints directly related to the content of the video. To deal with these semantic constraints, a fine-grained adaptation, which can go down to the level of video objects, is necessary. The overall goal of this adaptation process is to provide users with adapted content that maximizes their Quality of Experience (QoE). This QoE depends at the same time on the level of the user's satisfaction in perceiving the adapted content, the amount of knowledge assimilated by the user, and the adaptation execution time. In video adaptation frameworks, the Adaptation Decision Taking Engine (ADTE), which can be considered as the "brain" of the adaptation engine, is responsible for achieving this goal. The task of the ADTE is challenging as many adaptation operations can satisfy the same semantic constraint, and thus arising in several feasible adaptation plans. Indeed, for each entity undergoing the adaptation process, the ADTE must decide on the adequate adaptation operator that satisfies the user's preferences while maximizing his/her quality of experience. The first challenge to achieve in this is to objectively measure the quality of the adapted video, taking into consideration the multiple aspects of the QoE. The second challenge is to assess beforehand this quality in order to choose the most appropriate adaptation plan among all possible plans. The third challenge is to resolve conflicting or overlapping semantic constraints, in particular conflicts arising from constraints expressed by owner's intellectual property rights about the modification of the content. In this thesis, we tackled the aforementioned challenges by proposing a Utility Function (UF), which integrates semantic concerns with user's perceptual considerations. This UF models the relationships among adaptation operations, user preferences, and the quality of the video content. We integrated this UF into an ADTE. This ADTE performs a multi-level piecewise reasoning to choose the adaptation plan that maximizes the user-perceived quality. Furthermore, we included intellectual property rights in the adaptation process. Thereby, we modeled content owner constraints. We dealt with the problem of conflicting user and owner constraints by mapping it to a known optimization problem. Moreover, we developed the SVCAT, which produces structural and high-level semantic annotation according to an original object-based video content model. We modeled as well the user's preferences proposing extensions to MPEG-7 and MPEG-21. All the developed contributions were carried out as part of a coherent framework called PIAF. PIAF is a complete modular MPEG standard compliant framework that covers the whole process of semantic video adaptation. We validated this research with qualitative and quantitative evaluations, which assess the performance and the efficiency of the proposed adaptation decision-taking engine within PIAF. The experimental results show that the proposed UF has a high correlation with subjective video quality evaluation.
The present thesis is based on four articles in the areas of labor economics, regional science and international trade. I make use of different micro-level data sets to evaluate reasons for performance disparities between firms and between workers and evaluate the interrelation of these disparities with characteristics of local labor markets. Chapter 1 of this thesis provides a discrimination between the effects of several agglomeration externalities on firms’ total factor productivity. The identification of TFP is not trivial, however. I thereby correct for biases due to unobserved output prices and the endogeneity of agglomeration economies. Traditional reasons, such as specialization, diversity and size of the county, as well as the more detailed Marshallian agglomeration economies, namely knowledge spillovers and labor market pooling, are jointly tested. It turns out that labor market pooling is the quantitatively most important agglomeration mechanism. It is captured by the correlation of the occupational composition between one county-industry and the rest of the county. The intuition behind it is that a plant readily finds suitable staff if sectors, which employ similar workers, have a large extent in the same region. Labor market pooling is still the dominant agglomeration force if the spatial boundaries of regions are changed. In general, the data demonstrate that the strength of agglomeration economies varies largely between sectors. Only for a subset of industries, some positive evidence is detected for knowledge spillovers. Chapter 2 analyzes labor market pooling in greater detail, but with a slightly different modeling than in chapter 1. Here, the central aspect of labor market pooling is based on the quality of workers and firms. The main questions are if there is a systematic matching in the labor market and if this matching pattern creates advantages for both parties. I devote attention to the identification of accurate quality measures: plants' total factor productivity and workers' fixed effect. Two different methods then yield evidence in favor of positive assortative matching. The correlation between both quality measures is positive. Wage gains amount up to 4% when both quality levels are equal. In a fairly general matching model, this shape of the wage curve arises due to complementarities of qualities in the production function. When generally higher productivities and wages in dense regions (caused by agglomeration economies and sorting) are not controlled for, the strength of matching and wage gains are overestimated. I also find that regional differences in matching quality cannot be attributed to the local density and unemployment rate. Chapter 3 applies several regression-based decomposition methods to analyze the impact of region-, worker-, firm- and sector-specific determinants on the wage level and the continuous increase in wage inequality between 1995 and 2007 in Germany. In contrast to prior studies, more than 50% of the wage dispersion and almost the entire increase in wage inequality are explained in this approach. Altogether, the entire growth of wage dispersion occurs within regions and changes in the composition of wage determinants are minor compared to changes in their returns. I find that occupational attributes are the most important wage determinant. Changes in the firm size premium in combination with assortative matching also depress wages in the bottom of the distribution while they increase wages at the top. Workers with an unemployment record or an occupation in the service, construction and logistics sectors particularly experience falling wages. Chapter 4 studies the effect of an expansion of imported intermediate inputs on establishments’ average task intensities and employment size in a middle-income country. I use confidential matched employer-employee data and information on trade transactions for the universe of Brazilian firms. Propensity Score Matching indicates that import expansion leads to an overall employment growth, higher intensities in routine and non-routine manual tasks and an increased share of intermediates exports. Thus my findings point out that intermediates imports represent onshored instead of offshored tasks. This result remains unchanged regardless of whether imports from high- or low-wage countries are considered.
Die vorliegende Studie untersucht die Rückwanderungsintention von Arbeitsmigranten in Deutschland unter dem Gesichtspunkt der Lebenszufriedenheit. Am Beispiel von München wird die individuelle Lebenssituation von spanischen Arbeitsmigranten beleuchtet, die seit 2008 nach Deutschland gekommen sind. Denn trotz der wirtschaftlichen Stärke Deutschlands gelingt es oftmals nicht die dringend benötigten ausländischen Fachkräfte auch zu halten. Was also treibt so zahlreiche Zuwanderer wieder zurück? Diese Frage muss dabei immer vor dem Hintergrund betrachtet werden, dass eine Migration immer auch eine Lebensentscheidung darstellt, die sich für den Einzelnen am Ende lohnen soll. Die zentralen Forschungsfragen lauten: • Wie zufrieden sind die spanischen Arbeitsmigranten mit ihrem Leben in Deutschland? • Wie orientieren sie sich in Hinblick auf die Zukunft – Bleiben oder Zurückkehren? • Welches sind die entscheidenden Faktoren dafür? Zur Beantwortung dieser Fragen werden verschiedene Theorien aus der Migrations- und Glücksforschung diskutiert und daraus ein integriertes Erklärungsmodell entwickelt, welches die Grundlage für die empirische Untersuchung bildet. Somit wird das Phänomen Migration nicht nur als Ergebnis einer ökonomisch-rationalen Nutzenabwägung betrachtet, sondern es können auch andere Aspekte berücksichtigt werden – etwa die soziale Einbindung oder persönliche Ziele der Individuen. Die Ergebnisse der Studie werden in einem aus der qualitativen Analyse hervorgegangenen Kategoriensystem aufbereitet und mit Ankerbeispielen und Zitaten veranschaulicht. Abschließend erfolgt die Interpretation der Ergebnisse, wobei sich herausstellt, dass den nicht-ökonomischen Faktoren bei der Rückwanderungsentscheidung von Arbeitsmigranten die weit größere Rolle zukommt.
In the Web 2.0 era, platforms for sharing and collaboratively annotating images with keywords, called tags, became very popular. Tags are a powerful means for organizing and retrieving photos. However, manual tagging is time consuming. Recently, the sheer amount of user-tagged photos available on the Web encouraged researchers to explore new techniques for automatic image annotation. The idea is to annotate an unlabeled image by propagating the labels of community photos that are visually similar to it. Most recently, an ever increasing amount of community photos is also associated with location information, i.e., geotagged. In this thesis, we aim at exploiting the location context and propose an approach for automatically annotating geotagged photos. Our objective is to address the main limitations of state-of-the-art approaches in terms of the quality of the produced tags and the speed of the complete annotation process. To achieve these goals, we, first, deal with the problem of collecting images with the associated metadata from online repositories. Accordingly, we introduce a strategy for data crawling that takes advantage of location information and the social relationships among the contributors of the photos. To improve the quality of the collected user-tags, we present a method for resolving their ambiguity based on tag relatedness information. In this respect, we propose an approach for representing tags as probability distributions based on the algorithm of Laplacian score feature selection. Furthermore, we propose a new metric for calculating the distance between tag probability distributions by extending Jensen-Shannon Divergence to account for statistical fluctuations. To efficiently identify the visual neighbors, the thesis introduces two extensions to the state-of-the-art image matching algorithm, known as Speeded Up Robust Features (SURF). To speed up the matching, we present a solution for reducing the number of compared SURF descriptors based on classification techniques, while the accuracy of SURF is improved through an efficient method for iterative image matching. Furthermore, we propose a statistical model for ranking the mined annotations according to their relevance to the target image. This is achieved by combining multi-modal information in a statistical framework based on Bayes' rule. Finally, the effectiveness of each of mentioned contributions as well as the complete automatic annotation process are evaluated experimentally.
Making multimedia data available online becomes less expensive and more convenient on a daily basis. This development promotes web phenomenons such as Facebook, Twitter, and Flickr. These phenomena and their increased acceptance in society in turn leads to a multiplication of the amount of available images online. This vast amount of, frequently public and therefore searchable, images already exceeds the zettabyte bound. Executing a similarity search on the magnitude of images that are publicly available in the Internet, and receiving a top quality result is a challenge that the scientific community has recently attempted to rise to. One approach to cope with this problem assumes the use of distributed heterogeneous Content Based Image Retrieval system (CBIRs). Following from this anticipation, the problems that emerge from a distributed query scenario must be dealt with. For example the involved CBIRs’ usage of distinct metadata formats for describing their content, as well as their unequal technical and structural information. An addition issue is the individual metrics that are used by the CBIRs to calculate the similarity between pictures, as well as their specific way of being combined. Overall, receiving good results in this environment is a very labor intensive task which has been scientifically but not yet comprehensively explored. The problem primarily addressed in this work is the collection of pictures from CBIRs, that are similar to a given picture, as a response to a distributed multimedia query. The main contribution of this thesis is the construction of a network of Content Based Image Retrieval systems that are able to extract and exploit the information about an input image’s semantic concept. This so called semantic CBIRn is mainly composed of CBIRs that are configured by the semantic CBIRn itself. Complementarily, there is a possibility that allows the integration of specialized external sources. The semantic CBIRn is able to collect and merge results of all of these attached CBIRs. In order to be able to integrate external sources that are willing to join the network, but are not willing to disclose their configuration, an algorithm was developed that approximates these configurations. By categorizing existing - as well as external - CBIRs and analyzing incoming queries, image queries are exclusively forwarded to the most suitable CBIRs. In this way, images that are not of any use for the user can be omitted beforehand. The hereafter returned images are rendered comparable in order to be able to merge them to one single result list of images, that are similar to the input image. The feasibility of the approach and the hereby obtained improvement of the search process is demonstrated by a prototypical implementation and its evaluation using classified images of ImageNet. Using this prototypical implementation an augmentation of the number of returned images that are of the same semantic concept as the input images is achieved by a factor of 4.75 with respect to a predefined non-semantic CBIRn.
Das deutsche Notwehrrecht weist ein bedeutsames Spezifikum auf. Im Gegensatz zu den §§ 228, 904 BGB und vielen ausländischen Rechtsordnungen, verlangt § 32 StGB prinzipiell keine Güterabwägung. Das sich durch das Merkmal der Erforderlichkeit manifestierende Übermaßverbot setzt weder eine Güterproportionalität zwischen den rechtlichen Interessen des Angegriffenen und denen des Angreifers noch eine Schadensproportionalität voraus. Die Tatsache, dass 32 StGB keine Güterabwägung vorsieht, wirft zahlreiche Fragen auf. Ist dies als ein ernsthaftes Manko des Notwehrrechts zu verstehen, oder sind bestimmte Lösungen vorstellbar, die ggf. von einer gewissen Einschränkung des Notwehrrechts ausgehen? Wenn solche Einschränkungen in Frage kommen, nach welchen Kriterien könnte man sie bestimmen? Wo liegen die Grenzen etwaiger Schranken des Notwehrrechts? Geht es dabei um festgesetzte und änderungsfeste Grenzen? Können vieleicht neue, zusätzliche Konstellationen in Betracht gezogen werden, die diese Grenzen noch erweitern können? Das Ziel der vorliegenden Untersuchung ist es, entsprechende Antworten auf die oben gestellten Fragen anzubieten. Die vorliegende Untersuchung gliedert sich in sechs Kapitel. Nach der Problemstellung und der einführenden Abhandlung zur Notwehr als Strafrechtsbegriff werden die allgemeinen Fragen der sog. sozialethischen Einschränkungen des Notwehrrechts behandelt. Im Anschluss daran werden die Aspekte des Schutzes von Eigentum im Falle der sog. Bagatellangriffe erörtert. Danach werden die Einschränkungen des Notwehrrechts aus verfassungsrechtlichen Gründen untersucht. Schließlich werden im Rahmen der Untersuchung auch andere sozialethische Einschränkungen der Notwehr und darunter eine besonders intensiv diskutierte Fallgruppe der sog. Notwehrprovokation behandelt. Im Rahmen der Schlussbetrachtung werden die gewonnenen Ergebnisse noch einmal zusammengefasst dargestellt.
In this thesis, we investigates plane drawings of undirected and directed graphs on cylinder surfaces. In the case of undirected graphs, the vertices are positioned on a line that is parallel to the cylinder’s axis and the edge curves must not intersect this line. We show that a plane drawing is possible if and only if the graph is a double-ended queue (deque) graph, i. e., the vertices of the graph can be processed according to a linear order and the edges correspond to items in the deque inserted and removed at their end vertices. A surprising consequence resulting from these observations is that the deque characterizes planar graphs with a Hamiltonian path. This result extends the known characterization of planar graphs with a Hamiltonian cycle by two stacks. By these insights, we also obtain a new characterization of queue graphs and their duals. We also consider the complexity of deciding whether a graph is a deque graph and prove that it is NP-complete. By introducing a split operation, we obtain the splittable deque and show that it characterizes planarity. For the proof, we devise an algorithm that uses the splittable deque to test whether a rotation system is planar. In the case of directed graphs, we study upward plane drawings where the edge curves follow the direction of the cylinder’s axis (standing upward planarity; SUP) or they wind around the axis (rolling upward planarity; RUP). We characterize RUP graphs by means of their duals and show that RUP and SUP swap their roles when considering a graph and its dual. There is a physical interpretation underlying this characterization: A SUP graph is to its RUP dual graph as electric current passing through a conductor to the magnetic field surrounding the conductor. Whereas testing whether a graph is RUP is NP-hard in general [Bra14], for directed graphs without sources and sink, we develop a linear-time recognition algorithm that is based on our dual graph characterization of RUP graphs.