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Der Zusammenbruch des Systems der Arbeiterselbstverwaltung und der sich daran anschließende Transformationsprozess zogen einen sektoralen Strukturwandel der kroatischen Volkswirtschaft nach sich. Die forcierte Deindustrialisierung und Tertiarisierung führte allerdings zu massiven Fehlentwicklungen, die bis eute die wirtschaftliche Lage des Landes bestimmen.
In der Untersuchung wird daher der Frage nachgegangen, inwieweit ein Tertiarisierungsprozess für ein Transformationsland wie Kroatien als Option für eine erfolgreiche wirtschaftliche Entwicklung zu bewerten ist. Dafür müssen zunächst grundlegende theoretische Ansätze zu den Themengebieten Wachstum und Strukturwandel beschrieben, beurteilt und systematisiert werden. Hierbei zeigt sich, dass neuere modelltheoretische Untersuchungen weiterhin an der demand bias- und productivity bias-Hypothese gemäß Fourastié (1949) und Baumol (1967) ansetzen, um die Triebkräfte der wirtschaftlichen Entwicklung hin zu einer Dienstleistungsgesellschaft zu erklären. Die Autorin identifiziert dabei zwei Theoriestränge: Einerseits wird in der Literatur versucht, die Überlegungen zum strukturellen Wandel mit der Wachstumstheorie "zu versöhnen", d. h. zu verbinden. Andererseits werden "Heilungschancen" der Baumolschen Kostenkrankheit auf Basis der Determinanten der Endogenen Wachstumstheorie und der Innovationsmerkmale von Dienstleistungen formuliert. Empirische Untersuchungen zum sektoralen Strukturwandel in ausgewählten europäischen Wohlfahrtsstaatssystemen zeigen weiterhin auf, dass die wirtschaftliche Entwicklung eines Landes zudem von gesellschaftlichen und politischen Faktoren bestimmt wird.
Im zweiten Teil der Studie werden mithilfe des theoretischen Instrumentariums die drei Entwicklungsstufen der kroatischen Volkswirtschaft seit dem Zweiten Weltkrieg nachgezeichnet. Dabei zeigt sich, dass in der ersten Phase die Mängel der Arbeiterselbstverwaltung einen strukturellen Wandel und Produktivitätswachstum behinderten, während in den 1990er Jahren insbesondere die verfehlte Wirtschafts- und Sozialpolitik zu negativen volkswirtschaftlichen und gesellschaftlichen Folgen führte. Während des forcierten Integrationsprozesses in die EU wirkte sich die in der zweiten Hälfte der 2000er-Jahre einsetzende Wirtschaftskrise negativ auf den kroatischen Arbeitsmarkt aus. Die Analyse der Innovationsfähigkeit der kroatischen Wirtschaft sowie die Zusammenfassung der zentralen Erkenntnisse im letzten Teil der Studie zeigen auf, dass Wachstum und Beschäftigung zukünftig gefördert werden können, wenn in Kroatien der strukturelle und gesellschaftliche Wandel weiter fortgesetzt wird.
Primäres Ziel und Aufgabe dieser Arbeit ist ... die Entwicklung einer neuen Recyclingmethode für PET, die die Nachteile der bisherigen Verwertungsmethoden vermeidet und unter weitgehendem Erhalt der bereits erbrachten Syntheseleistung definierte Oligomere liefert. Aus diesen können in Folge hochwertige Produkte hergestellt werden.
Vertrauen ist eine wesentliche Ressource für die Zusammenarbeit zwischen Anbietern und Kunden. In der postmodernen Gesellschaft sind beide Seiten auf Kooperation angewiesen. Ohne Vertrauen führen gemeinsame Beziehungen jedoch selten zu den erwünschten Resultaten. Alexander Rossmann zeigt auf, wie sich das Vertrauen von Kunden stimulieren lässt und welche Verhaltensweisen zu vermeiden sind. Dabei werden personale und organisationale Vertrauensstrategien konzeptionell entwickelt und am Beispiel der IT-Branche empirisch untersucht. Eine Analyse der Auswirkungen von Vertrauen bietet differenzierte Einblicke in die Chancen und Risiken von Vertrauen aus Anbieter- und Kundenperspektive.
Globale Beschaffungsstrukturen, Konsumgüterproduktion in Entwicklungsländern, Unternehmensethik und Sozialstandards - Sachverhalte, die im Zeitalter der Globalisierung an Bedeutung gewinnen und darauf hinweisen, dass Länder der Dritten Welt eine zunehmend wichtige Rolle in weltweiten Wertschöpfungsketten westlicher Unternehmen einnehmen. Dieser wachsende Anteil vieler Entwicklungsländer am Welthandel ist entwicklungspolitisch als großer Fortschritt zu sehen, weil diese stärker als in der Vergangenheit an Wachstum und Wohlstand teilhaben können. Leider verläuft dieser Aufholprozess aber nicht störungsfrei, da der damit einhergehende Verlagerungsprozess arbeitsintensiver Produktion oftmals zur Folge hat, dass westliche Konsumgüter in diesen Ländern unter menschenrechtlich untragbaren Bedingungen hergestellt werden, um Arbeits- und Herstellungskosten auf ein Minimum zu reduzieren sowie arbeitsrechtlichen Regelungen auf globaler Ebene zu entgehen. In einer übergeordneten Sichtweise geht es also um das Spannungsfeld von Ökonomie und Ethik, was seit langem Leitthema der Wirtschaftsethik ist. Dabei stellt sich die Frage, inwieweit diese einen Beitrag zu einer Globalisierung mit menschlichem Antlitz leisten kann. Zu diesem Zweck untersucht das vorliegende Buch, ob das Managementkonzept der Corporate Social Responsibility (CSR) zu einer Lösung und schrittweisen Annäherung von Ökonomie und Ethik im Globalisierungskontext führen kann. Angesichts der mangelnden Durchsetzbarkeit staatlich dirigistischer Strukturen auf internationaler Ebene wird daher die Frage nach dem Ort der Verantwortung neu gestellt und damit beantwortet, dass es vor allem Unternehmen und deren weltweiten Netzwerke sind, die durch ihr ethisch reflektiertes Handeln zu einer sozialeren Globalisierung beitragen können. Um diese jedoch verstärkt dazu zu motivieren, dieser Verantwortung nachzukommen, liegt ein besonderer Schwerpunkt dieses Buches auf der Entwicklung des CSR Business Case und der Frage, welche Faktoren entscheidend sind, wenn es um den betriebswirtschaftlichen Erfolg ethischen Engagements geht. Dafür ist es neben einer prozessorientierten Umsetzung in Produktion und Beschaffung ebenso wichtig, dieses Engagement mit Hilfe CSR-relevanter Marketinginstrumente an die Verbraucher zu kommunizieren und damit in ihr Bewusstsein sowie auf ihren Konsum- und Kaufradar zu bringen. In diesem Sinne werden die jeweils erforderlichen Implementierungsschritte und -instrumente so detailliert ausgearbeitet, dass sie unmittelbare Praxisrelevanz bekommen und zeigen, wie man von der hohen Abstraktionsebene der Globalisierung auf die Umsetzungsebene der Unternehmen gelangt und wie mit der anfänglichen Polarität zwischen Ethik und Ökonomie umgegangen werden kann. Somit soll das, was kurzfristig als Dilemma und Zielkonflikt erscheint, langfristig in ein produktives Handlungsfeld übersetzt werden, indem v.a. mittelständischen Unternehmen konkrete CSR-Handlungskompetenz an die Hand gegeben wird, weil diese aufgrund ihres enormen Stellenwerts in der deutschen Wirtschaft eine wichtige Rolle einnehmen können, CSR auf breiter Ebene durchzusetzen.
In modern collaborative production environments where industrial robots and humans are supposed to work hand in hand, it is mandatory to observe the robot’s workspace at all times. Such observation is even more crucial when the robot’s main position is also dynamic e.g. because the system is mounted on a movable platform. As current solutions like physically secured areas in which a robot can perform actions potentially dangerous for humans, become unfeasible in such scenarios, novel, more dynamic, and situation aware safety solutions need to be developed and deployed.
This thesis mainly contributes to the bigger picture of such a collaborative scenario by presenting a data-driven convolutional neural network-based approach to estimate the two-dimensional kinematic-chain configuration of industrial robot-arms within raw camera images. This thesis also provides the information needed to generate and organize the mandatory data basis and presents frameworks that were used to realize all involved subsystems. The robot-arm’s extracted kinematic-chain can also be used to estimate the extrinsic camera parameters relative to the robot’s three-dimensional origin. Further a tracking system, based on a two-dimensional kinematic chain descriptor is presented to allow for an accumulation of a proper movement history which enables the prediction of future target positions within the given image plane. The combination of the extracted robot’s pose with a simultaneous human pose estimation system delivers a consistent data flow that can be used in higher-level applications.
This thesis also provides a detailed evaluation of all involved subsystems and provides a broad overview of their particular performance, based on novel generated, semi automatically annotated, real datasets.
Advancements in Internet of Things (IoT), cloud and mobile computing have fostered the digital enrichment—or “digitization”—of physical products, which are gaining increasing relevance in practice. According to recent studies, global IoT spending will exceed USD 1 Trillion by 2021 and there will be over 25 billion IoT connections (KPMG, 2018). Porter and Heppelmann (2014) state that IT is “revolutionizing products [as …] IT is becoming an integral part of the product itself.” Senior business executives like GE’s former CEO Jeff Immelt (2015) are even proposing that “every industrial company in the coming age is also going to become a software and analytics company.” This reflects the increasing relevance of IT components’ (i.e., software, data analytics, cloud computing) integration into previously purely physical products. We call IT-enriched physical products, “digitized” products to differentiate them from purely intangible “digital” products, such as digital music, e-books, and software. Examples of digitized products include the Philips Hue smartphone-controllable lightbulb, Audi Connect internet-connected cars, or Rolls-Royce’s sensor-enabled pay per use jet engines.
Digitized products provide their producers with a wide range of opportunities to offer new functionality and product capabilities (e.g., autonomy) that traditional, physical products do not exhibit (Porter and Heppelmann, 2014). In addition, the digitization of products allows producers to continuously repurpose their offerings, by extending and/or changing the product functionality and, thus, enabling new value creation opportunities. Based on their re-programmability and connectivity, digitized products “remain essentially incomplete […] throughout their lifetime as users continue to add and delete […] and change […] functional capabilities” (Yoo, 2013). For instance, the Philips Hue connected lightbulb enables remote control of basic functions (e.g., switching on and off the light) as well as setting more advanced light scenes for day-to-day tasks (e.g., relax, read) via Amazon’s Alexa artificial intelligence assistant (Signify, 2019), offerings that were not intended use cases when Signify (previously known as Philips Lighting) created Hue in 2012. Thus, digitized products present limitless potentials for new functionality and unforeseen use cases, which provides them with a huge innovation capacity.
Despite the limitless potentials offered by digitized products, there has been a slow uptake of digitized products by businesses so far (Jernigan et al., 2016; Mocker et al., 2019). According to a 2016 MIT Sloan Management Review report (Jernigan et al., 2016) only 24% of the investigated firms were actively using IoT technologies – a key technology for digitized products. In a more recent research study Mocker et al. (2019) found that the median revenue share from digital offerings (i.e., solutions based on IT enriched products) in large companies only accounted for 5% of the total revenue of the investigated companies.
The slow uptake of digitized products might be explained by the challenges that firms face regarding the changing nature of digitized products. Pervasive digital technologies (such as IoT) change the nature of products by adding new functionality that was previously not part of the value proposition of the products/services (e.g., a pair of shoes embedded with sensors and connectivity allows joggers to have access to data regarding their run distance, speed, etc.) (Yoo et al., 2012). The addition of new functionality and use cases of digitized products makes it harder for producers to design and develop relevant products (Hui 2014). As described in the paper ‘Do Your Customers Actually Want a “Smart” Version of Your Product?’, “just because [firms] can make something with IoT technology doesn’t mean people will want it.” (Smith, 2017).
The shift in digitized products’ nature poses new challenges for producers along the entire product development process (Porter and Heppelmann, 2015; Yoo et al., 2012) and create a paradox in product digitization, described by Yoo et al. (2012) as the paradox of pace: while technology accelerates the rate of innovation, companies need to spend more time to digitize their products, extending time to market. The production of these digitized products also becomes more challenging, e.g., as companies need to deal with different clock-speeds of software and hardware development (Porter and Heppelman, 2015). The above-mentioned challenges suggest that producers need to better understand how they can generate value from their digitized products’ generative potentials.
The body of literature on digitized products has been growing in recent years. For instance, Herterich et al. (2016) investigate how digitized product affordances (i.e., potentials) enable industrial service innovation; Nicolescu et al. (2018) explore the emerging meanings of value associated with IoT; and Benbunan-Fich (2019) studies the impact of basic wearable sensors on the quality of the user experience. However, it remains unclear what it takes for firms to generate value with their digitized product potentials. This dissertation investigates this research gap.
The digital age makes it possible to be globally networked at any time. Digital communication is therefore an important aspect of today’s world. Hence, the further development and expansion of this is becoming increasingly important. Even within a wireless system, copper channels are important as part of the overall network. Given the need to keep pushing at the current limitations, careful design of the cables in connection with an adapted coding of the bits is essential to transmit more and more data.
One of the most popular and widespread cabling technologies is symmetrical copper cabling [1, pp. 8-15]. It is also known as Twisted Pair and it is of immense importance for the cabling of communication networks.
At the time of writing this thesis, data rates of up to 10 GBit/s over a transmission distance of 100 m and 40 GBit/s over a transmission distance of 30 m are standardized for symmetrical copper cabling [2]. Other lengths are not standardized. Short lengths in particular are of great interest for copper cables, because copper cables are usually used for short distances, such as between computers and the campus network or within data centres.
This work has focused on the transmission of higher order Pulse Amplitude Modulation and the associated transmission performance. The central research question is:“how well can we optimize the transmission technique in order to be able to maximise the data bandwidth over Ethernet cable and, given that remote powering is also a significant application of these cables, how much will the resulting heating affect this transmission and what can be done to mitigate that?”
To answer this question, the cable parameters are first examined. A series of spectral measurements, such as Insertion Loss, Return Loss, Near End Crosstalk and Far End Crosstalk, provide information about the electromagnetic interference and the influence of the ohmic resistance on the signal. Based on these findings, the first theoretical statements and calculations can be made. In the next step, data transmissions over different transmission lengths are realized. The examination of the eye diagrams of the different transmission approaches ultimately provides information about the signal quality of the transmissions. An overview of the maximum transmission rate depending on the transmission distance shows the potential for different applications.
Furthermore, the simultaneous transmission of energy and data is a significant advantage of copper. However, the resulting heat development has an influence on the data transmission. Therefore, the influence of the ambient temperature of cables is investigated in the last part and changes in the signal quality are clarified.
The targeted design of monodisperse, mesoporous silica microspheres (MPSMs) as HPLC separation phases is still a challenge. The MPSMs can be generated via a multi-step template-assisted method. However, this method and the factors affecting the individual process steps and resulting material properties are scarcely understood, and specific control of the complex multi-step process has been hardly discussed. In this work, the key synthesis steps were systematically investigated by means of statistical Design of Experiment (DoE). In particular, three steps were considered in detail: 1) the synthesis of porous poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) (p(GMA-co-EDMA)) particles, which as template particles, determine the structure for the final MPSMs. In this context, functional models were generated, which allow the control of the template properties pore volume, pore size and specific surface area. 2) In the presence of amino-functionalized template particles, the sol-gel process was carried out under Stöber process conditions. The water to tetraethyl orthosilicate (TEOS) ratio, as well as the concentration of ammonia as basic catalyst were varied according to a face-centered central composite design (FCD). The incorporation of silica nanoparticles (SNPs) into the pore network of the porous polymers was investigated by scanning electron microscopy (SEM), evaluation of the pore properties assessed by nitrogen sorption measurements and determination of the inorganic content by thermogravimetric analysis (TGA). Here, the material properties, such as the amount of attached silica, can be specifically controlled in the resulting organic/silica hybrid material (hybrid beads, HBs). Furthermore, depending on the sol-gel conditions three, potentially four, reaction regimes were identified, leading to different HBs. These range from porous polymer particles coated with a thin protective silica layer, to interpenetrating networks of polymer and silica, to potential particles consisting of a porous polymer core coated with a silica shell. Also, the effects of the use of different precursors and solvents on silica incorporation were investigated. 3) To obtain MPSMs from the HBs, the organic polymer template was removed by calcination. The effects of sol-gel process conditions on the resulting MPSMs were evaluated and relationships between process conditions and material properties were shown in predictive models. Fully porous, spherical, monodisperse silica particles with sizes ranging from 0.5 µm to 7.8 µm and pore sizes from 3.5 nm to 72.4 nm can be prepared specifically. Subsequent to organo-functionalization, prepared MPSMs were applied as reversed-phase HPLC column materials. Here, the columns were successfully applied for the separation of proteins and amino acids. The separation performance of the materials depends largely on the property profile of the MPSMs, which is predetermined during the preparation of the HBs.
Gegenstand dieser Arbeit ist die Darstellung und Charakterisierung einheitlicher, mesoporöser Silica-Partikel (MPSM) im Mikrometerbereich mit maßgeschneiderten Partikel- und Porendesign für die Hochleistungsflüssigkeitschromatographie. Die Synthese umfasst die Einlagerung von Silica-Nanopartikeln (SNP) in poröse organische Template, welche anschließend bei 600°C zersetzt werden. Die Impfsuspensionspolymerisation von Polystyrol-Partikeln, unter Verwendung von Glycidylmethacrylat, Ethylenglycoldimethacrylat und Porogenen, ermöglicht die Herstellung hochgradig einheitlicher, poröser p(GMA-co-EDMA)-Template. Der Einfluss wesentlicher Faktoren, einschließlich des Monomer-Porogen-Verhältnisses, des Monomerverhältnisses und der Porogenzusammensetzung, werden systematisch untersucht sowie ihre Auswirkungen auf die Porengröße, das Porenvolumen und die spezifische Oberfläche erläutert. Die Anbindung aminofunktionalisierter Substanzen erfolgt durch die Ringöffnung der Epoxidgruppe. Im anschließenden basischen Sol-Gel-Prozess werden die Silica-Nanopartikel aufgrund der Ladungsunterschiede in die funktionalisierten p(GMA-co-EDMA)-Template eingebaut. Die Partikelgröße der SNP beeinflusst wesentlich die Poreneigenschaften der MPSM und hängt von drei Faktoren ab: (i) der Wachstumsgeschwindigkeit in der kontinuierlichen Phase, die durch die Einstellungen des Sol-Gel-Prozesses gesteuert wird, (ii) der Diffusionsrate, die durch elektrostatische Anziehung reguliert wird und vom Grad der Funktionalisierung abhängt und (iii) der Porosität des Polymer-Templats. Die gezielte Anpassung der Poreneigenschaften durch die Prozesseinstellungen erlaubt die präzise Herstellung von MPSM, die auf spezifische Trennherausforderungen zugeschnitten werden und somit die Qualität der HPLC verbessern. Die vorgestellte Synthesestrategie ermöglicht, aufgrund des stufenweisen molekularen Aufbaus, eine bessere Adaption der stationären Phase an spezifische Trennherausforderungen.
After more than three decades of electronic design automation, most layouts for analog integrated circuits are still handcrafted in a laborious manual fashion today. This book presents Self-organized Wiring and Arrangement of Responsive Modules (SWARM), a novel interdisciplinary methodology addressing the design problem with a decentralized multi-agent system. Its basic approach, similar to the roundup of a sheep herd, is to let autonomous layout modules interact with each other inside a successively tightened layout zone. Considering various principles of self-organization, remarkable overall solutions can result from the individual, local, selfish actions of the modules. Displaying this fascinating phenomenon of emergence, examples demonstrate SWARM’s suitability for floorplanning purposes and its application to practical place-and-route problems. From an academic point of view, SWARM combines the strengths of procedural generators with the assets of optimization algorithms, thus paving the way for a new automation paradigm called bottom-up meets top-down.
A distinctive highlight of the dissertation at hand is the investigation of multiple apparel supply chain actors incorporating the views of a global apparel retailer in Europe and multiple suppliers in Vietnam and Indonesia.
More specifically, the dissertation presents a coherent investigation starting with the depiction of a conceptual framework for social management strategies as a means for social risk management (SRM), exclusively aiming at the apparel industry. In accordance to the identified research gaps and suggested research directions from the conceptual framework, the role of the apparel sourcing agent for social management strategies was analysed by conducting a multiple case study approach with evidence from Vietnam and Europe, ultimately suggesting ten propositions. Whereas a further multiple case study data collection in Vietnam, Indonesia and Europe allowed for the investigation of buyer-supplier relationships with regards to social compliance strategies by using core tenets of agency theory to interpret the findings and outline ten propositions. Based on the development of a conceptual framework on social SSCM in the apparel industry, the formulation of related 20 propositions with evidence from crucial developing (apparel sourcing) countries, and the application of agency theory which has been declared as a shortfall in this context, this thesis contributes with further grounding to SSCM theory and substantially contributes to the debate by addressing numerous research gaps.
Reconstructing 3D face shape from a single 2D photograph as well as from video is an inherently ill-posed problem with many ambiguities. One way to solve some of the ambiguities is using a 3D face model to aid the task. 3D morphable face models (3DMMs) are amongst the state of the art methods for 3D face reconstruction, or so called 3D model fitting. However, current existing methods have severe limitations, and most of them have not been trialled on in-the-wild data. Current analysis-by- synthesis methods form complex non linear optimisation processes, and optimisers often get stuck in local optima. Further, most existing methods are slow, requiring in the order of minutes to process one photograph.
This thesis presents an algorithm to reconstruct 3D face shape from a single image as well as from sets of images or video frames in real-time. We introduce a solution for linear fitting of a PCA shape identity model and expression blendshapes to 2D facial landmarks. To improve the accuracy of the shape, a fast face contour fitting algorithm is introduced. These different components of the algorithm are run in iteration, resulting in a fast, linear shape-to- landmarks fitting algorithm. The algorithm, specifically designed to fit to landmarks obtained from in-the-wild images, by tackling imaging conditions that occur in in-the-wild images like facial expressions and the mismatch of 2D–3D contour correspondences, achieves the shape reconstruction accuracy of much more complex, nonlinear state of the art methods, while being multiple orders of magnitudes faster.
Second, we address the problem of fitting to sets of multiple images of the same person, as well as monocular video sequences. We extend the proposed shape-to-landmarks fitting to multiple frames by using the knowledge that all images are from the same identity. To recover facial texture, the approach uses texture from the original images, instead of employing the often-used PCA albedo model of a 3DMM. We employ an algorithm that merges texture from multiple frames in real-time based on a weighting of each triangle of the reconstructed shape mesh.
Last, we make the proposed real-time 3D morphable face model fitting algorithm available as open-source software. In contrast to ubiquitous available 2D-based face models and code, there is a general lack of software for 3D morphable face model fitting, hindering a widespread adoption. The library thus constitutes a significant contribution to the community.
Product-Service Systems (PSS) in the fashion industry : an analysis of intra-organizational factors
(2018)
The fashion industry is a vast industry that has grown tremendously over the last decades. This growth causes significant environmental impact since the production of clothes involves high input of energy, water, chemicals and generates great volumes of waste. Even though fashion firms have started to address this challenge by adopting environmental standards, it has turned out that the sole use of eco-friendly material and new manufacturing techniques is insufficient. Instead, sustainable business models are increasingly gaining attention to solve the environmental problems. Offers to rent, swap, repair or redesign clothes are among the most prominent and promising examples. For analytical purposes, these concepts can be assigned to the growing research stream of Product-Service Systems (PSS) that shift the focus from the pure sale of a product toward complementary or substitutional service offers. This decouples customer satisfaction from material consumption, prolongs the garments' lifetime and thus diminishes both material input and appertaining waste. Besides environmental sustainability, PSS imply potential economic benefits for organizations. Particularly in highly competitive industries like the fashion industry, PSS allow firms to differentiate, better compete with cost pressure and mitigate the risk of being imitated by rivels since service is more difficult to replicate. However, fashion PSS are still mainly operated in a niche market by small firms and have yet to be anchored in the mainstream fashion industry.
Die konzeptionelle Integration von Ethik in die Personalwirtschaftslehre stellt eine bislang ungelöste Herausforderung dar. Daher verwundert es nicht, dass die Diskussion ethischer Fragestellungen in der Personalwirtschaftslehre weitgehend unsystematisch und theoretisch unterbestimmt erfolgt. Auf dieser Erkenntnis aufbauend entwickelt der Autor in seinem Buch das Forschungsprogramm der Personalethik. Dieses Forschungsprogramm geht gerade nicht von einer Integration von Ethik in die Personalwirtschaftslehre aus, sondern nähert sich den ethischen Problemen der Personalwirtschaftslehre aus einer unternehmensethischen Perspektive. Dadurch können bisherige Erkenntnisse zur Ethik in der Personalwirtschaftslehre innerhalb eines systematischen Bezugsrahmens (re-)interpretiert werden. Zudem bietet die Personalethik einen integrierten und theoretisch fundierten Bezugsrahmen für künftige Forschungen.
Pendeln im Alter : eine Fallstudie zu transnationaler Migration zwischen Deutschland und der Türkei
(2016)
Alter und Migration sind bisher kaum in Bezug zueinander gesetzt worden. Wie wirken sich migrationsspezifische Faktoren auf Alltag und Lebensplanung von Rentner/innen aus? Inwiefern beeinflussen Alter und Altern das Pendeln zwischen Herkunfts- und Einwanderungsland? Diese Fragen beantwortet Felicia Sparacio am Beispiel von Rentner/innen, die zwischen Deutschland und der Türkei pendeln. Sie untersucht deren soziale Netzwerke, konzentriert sich auf Alter in Verbindung mit Gesundheit, fragt nach Zugehörigkeiten und arbeitet die jeweils spezifische Prägung durch transnationale Migration und Alter heraus. Die Fallstudie erläutert zunächst Kontexte und Theorien zu Migration und Alter(n), bevor die beiden Felder gestützt durch empirische Ergebnisse analytisch verbunden werden.
This thesis studies concurrency control and composition of transactions in computing environments with long living transactions where local data autonomy of transactions is indispensable. This kind of computing architecture is referred to as a Disconnected System where reads are segregated -disconnected- from writes enabling local data autonomy. Disconnecting reads from writes is inspired by Bertrand Meyer's "Command Query Separation" pattern. This thesis provides a simple yet precise definition for a Disconnected System with a focus on transaction management. Concerning concurrency control, transaction management frameworks implement a'one concurrency control mechanism fits all needs strategy'. This strategy, however, does not consider specific characteristics of data access. The thesis shows the limitations of this strategy if transaction load increases, transactions are long lived, local data autonomy is required, and serializability is aimed at isolation level. For example, in optimistic mechanisms the number of aborts suddenly increases if load increases. In pessimistic mechanisms locking causes long blocking times and is prone to deadlocks. These findings are not new and a common solution used by database vendors is to reduce the isolation. This thesis proposes the usage of a novel approach. It suggests choosing the concurrency control mechanism according to the semantics of data access of a certain data item. As a result a transaction may execute under several concurrency control mechanisms. The idea is to introduce lanes similar to a motorway where each lane is dedicated to a certain class of vehicle with the same characteristics. Whereas disconnecting reads and writes sets the traffic's direction, the semantics of data access defines the lanes. This thesis introduces four concurrency control classes capturing the semantics of data access and each of them has an associated tailored concurrency control mechanism. Class O (the optimistic class) implements a first-committer-wins strategy, class R (the reconciliation class) implements a first-n-committers-win strategy, class P (the pessimistic class) implements a first-reader-wins strategy, and class E (the escrow class) implements a first-n-readers-win strategy. In contrast to solutions that adapt the concurrency control mechanism during runtime, the idea is to classify data during the design phase of the application and adapt the classification only in certain cases at runtime. The result of the thesis is a transaction management framework called O|R|P|E. A performance study based on the TPC-C benchmark shows that O|R|P|E has a better performance and a considerably higher commit rate than other solutions. Moreover, the thesis shows that in O|R|P|E aborts are due to application specific limitations, i.e., constraint violations and not due to serialization conflicts. This is a result of considering the semantics.
In dieser Arbeit wird ein Modell vorgestellt, das die Planung der direkten Wiederverwendung bei der Vermietung mobiler und langlebiger Investitionsgüter in Closed-Loop Supply Chains optimiert. Insbesondere die Entwicklung von Planungsalgorithmen zur Verbesserung der Vorhersagewahrscheinlichkeit zukünftiger Rücklieferungen und deren betriebswirtschaftliche Auswirkungen für Unternehmen stehen im Vordergrund. Das Optimierungsmodell betrachtet dabei sowohl die Positionierung des Unternehmens im Innen- als auch im Außenverhältnis und liefert die Entscheidungsgrundlage für entsprechende strategische Initiativen.
Context: Fast moving markets and the age of digitization require that software can be quickly changed or extended with new features. The associated quality attribute is referred to as evolvability: the degree of effectiveness and efficiency with which a system can be adapted or extended. Evolvability is especially important for software with frequently changing requirements, e.g. internet-based systems. Several evolvability-related benefits were arguably gained with the rise of service-oriented computing (SOC) that established itself as one of the most important paradigms for distributed systems over the last decade. The implementation of enterprise-wide software landscapes in the style of service-oriented architecture (SOA) prioritizes loose coupling, encapsulation, interoperability, composition, and reuse. In recent years, microservices quickly gained in popularity as an agile, DevOps-focused, and decentralized service-oriented variant with fine-grained services. A key idea here is that small and loosely coupled services that are independently deployable should be easy to change and to replace. Moreover, one of the postulated microservices characteristics is evolutionary design.
Problem Statement: While these properties provide a favorable theoretical basis for evolvable systems, they offer no concrete and universally applicable solutions. As with each architectural style, the implementation of a concrete microservice-based system can be of arbitrary quality. Several studies also report that software professionals trust in the foundational maintainability of service orientation and microservices in particular. A blind belief in these qualities without appropriate evolvability assurance can lead to violations of important principles and therefore negatively impact software evolution. In addition to this, very little scientific research has covered the areas of maintenance, evolution, or technical debt of microservices.
Objectives: To address this, the aim of this research is to support developers of microservices with appropriate methods, techniques, and tools to evaluate or improve evolvability and to facilitate sustainable long-term development. In particular, we want to provide recommendations and tool support for metric-based as well as scenario-based evaluation. In the context of service-based evolvability, we furthermore want to analyze the effectiveness of patterns and collect relevant antipatterns. Methods: Using empirical methods, we analyzed the industry state of the practice and the academic state of the art, which helped us to identify existing techniques, challenges, and research gaps. Based on these findings, we then designed new evolvability assurance techniques and used additional empirical studies to demonstrate and evaluate their effectiveness. Applied empirical methods were for example surveys, interviews, (systematic) literature studies, or controlled experiments.
Contributions: In addition to our analyses of industry practice and scientific literature, we provide contributions in three different areas. With respect to metric-based evolvability evaluation, we identified a set of structural metrics specifically designed for service orientation and analyzed their value for microservices. Subsequently, we designed tool-supported approaches to automatically gather a subset of these metrics from machine-readable RESTful API descriptions and via a distributed tracing mechanism at runtime. In the area of scenario-based evaluation, we developed a tool-supported lightweight method to analyze the evolvability of a service-based system based on hypothetical evolution scenarios. We evaluated the method with a survey (N=40) as well as hands-on interviews (N=7) and improved it further based on the findings. Lastly with respect to patterns and antipatterns, we collected a large set of service-based patterns and analyzed their applicability for microservices. From this initial catalogue, we synthesized a set of candidate evolvability patterns via the proxy of architectural modifiability tactics. The impact of four of these patterns on evolvability was then empirically tested in a controlled experiment (N=69) and with a metric-based analysis. The results suggest that the additional structural complexity introduced by the patterns as well as developers' pattern knowledge have an influence on their effectiveness. As a last contribution, we created a holistic collection of service-based antipatterns for both SOA and microservices and published it in a collaborative repository.
Conclusion: Our contributions provide first foundations for a holistic view on the evolvability assurance of microservices and address several perspectives. Metric- and scenario-based evaluation as well as service-based antipatterns can be used to identify "hot spots" while service-based patterns can remediate them and provide means for systematic evolvability construction. All in all, researchers and practitioners in the field of microservices can use our artifacts to analyze and improve the evolvability of their systems as well as to gain a conceptual understanding of service-based evolvability assurance.
Das Gehör ist mehr als jedes andere Sinnesorgan für die menschliche Sprache und ihre Entwicklung verantwortlich und stellt auf kleinstem Raum ein anatomisch und physiologisch einzigartiges Gebilde dar. Es beeindruckt vor allem durch seinen großen Dynamikbereich.
Während im Bereich der Hörschwelle der eben hörbare Schalldruck etwa 20 μPa beträgt, können die Drucke und Amplituden bis zur Schmerzgrenze noch etwa zweimillionenfach gesteigert werden. Derartige physiologische Schalldrücke sind jedoch immer noch verschwindend klein gegenüber den ebenfalls auf das Ohr einwirkenden statischen Luftdruckschwankungen, wie sie beispielsweise beim Treppensteigen, Zug- bzw. Autofahren, Fliegen oder beim Naseputzen vorkommen. Zwar führen diese zu einer veränderten Wahrnehmung, jedoch nicht zu einer Schäadigung des Ohrs. Diese Fähigkeit, trotz großer statischer Druckschwankungen in der Umgebung, gleichzeitig winzige physiologische Schalldrücke wahrnehmen zu können, ist hauptsächlich in den nichtlinearen, viskoelastischen Eigenschaften der Gelenke und Bänder des Mittelohrs sowie des Trommelfells begründet.
Das Ziel dieser Arbeit ist es, dieses nichtlineare Verhalten des Mittelohrs bei großen Belastungen und großen Verschiebungen durch nichtlineare, räumliche Ersatzmodelle auf mechanischer Basis abzubilden. Zur Charakterisierung der nichtlinearen Eigenschaften der Gerhörknöchelchenkette werden statische und dynamische Messungen an humanen Felsenbeinen durchgeführt. Ein besonderes Augenmerk ist auf die Charakterisierung der nichtlinearen, viskoelastischen Eigenschaften des Ringbands, des Trommelfells, der Trommelfellsehne und der beiden Mittelohrgelenke gerichtet. Im Blick auf die klinische Praxis wird zum einen anhand von Messergebnissen das Schädigungsrisiko bei einer Stapeschirurgie diskutiert sowie die Auswirkungen von Vorspannungen im Mittelohrapparat am Beispiel des aktiven Implantats Carina untersucht.
Unter der Zielsetzung der multimodalen, ortsaufgelösten optischen Spektroskopie für die markierungsfreie Charakterisierung biologischer Materialien nach Morphologie und Chemie werden vier Themenschwerpunkte behandelt.
1. Theorie der elastischen / inelastischen Lichtstreuung und laterale Auflösung in der Mikroskopie
2. Erweiterung eines Raman Mikroskops zu einem multimodalen spektralen Imaging System (MSIS) mit Photonenmigrations-Technologie
3. Erweiterung des MSIS zu Super-Resolution Raman Mikroskopie mit einer Festkörper-Immersionslinse
4. Anwendung des entwickelten MSIS auf biologische Materialien