In this article, the relationship between study programs in higher education and the risk of
holding a temporary contract is investigated in a comparative perspective. We fi nd that the
effects fi elds of study have on the type of contract can be better explained by their link to
occupational positions than by fi
city differentials. Furthermore, fi
elds of study
are more important in explaining the individual risk of holding a temporary contract in the
German rather than in the UK labor market. This may be attributable to the higher degree
of standardization of the German educational system
Counterfeit trade developed into a severe problem for many industries. While established security features such as holograms, micro printings or chemical markers do not seem to efficiently avert trade in illicit imitation products, RFID technology, with its potential to automate product authentications, may become a powerful tool to enhance brand and product protection. The following contribution contains an overview on the implication of product counterfeiting on affected companies, provides a starting point for a structured requirements definition for RFID-based anti-counterfeiting systems, and outlines several principal solution approaches that are discussed in greater detail in the subsequent chapters.
Offering services anonymously on the Internet using so-called location-hidden services requires complex protocols with many different nodes involved. These properties result in performance problems, e.g. a simple website request taking tens of seconds. This work describes a setup to measure the performance of hidden services using the worldwide Tor network. It analyzes the results and proposes changes to the protocol to improve the performance without losing anonymity.
Privacy on the Internet is becoming more and more important, as an increasing part of everyday life takes place over the Internet. Internet users lose the ability to control which information they give away about themselves or are even not aware that they do so. Privacy-enhancing technologies help control private information on the Internet, for example, by anonymizing Internet communication. Up to now, work on privacy-enhancing technologies has mainly focused on privacy of users requesting public services. This thesis introduces a new privacy risk that occurs when private persons run their own services. One example are instant messaging systems which allow users to exchange presence information and text messages in real time. These systems usually do not provide protection of presence information which is stored on central servers. As an alternative, decentralized instant messaging system designs mitigate this problem by having private persons provide instant messaging services to each other. However, providing a service as a private person causes new security problems as compared to providing a service as an organization or enterprise: First, the presence of such a service reveals information about the availability of the service provider. Second, the server location needs to be concealed in order to hide the whereabouts of a person. Third, the server needs to be specifically protected from unauthorized access attempts. This thesis proposes to use pseudonymous services as a building block for private services. Pseudonymous services conceal the location of a server that provides a specific service. The contribution made here is to analyze what parts of pseudonymous services, in particular Tor hidden services, are missing in order to apply them for private services. This analysis leads to three main problems for which solutions are proposed: First, known pseudonymous service designs do not scale to the expected number of private services which might be provided in the future. This thesis proposes a new approach to store hidden service descriptors in a distributed data structure rather than on central servers. A particular focus lies on the support of private entries which are required for private services. Second, pseudonymous services leak too much information about service identity during advertisement in the network and connection establishment by clients. The approach taken in this thesis is to reduce the information that a service publishes in the network to a minimum and prevent unauthorized clients from accessing a service already during connection establishment. These changes protect service activity and usage patterns from non-authorized entities. Third, pseudonymous services exhibit worse performance than direct service access. The contribution of this thesis is to measure performance, identify possible problems, and propose improvements.
This thesis investigates the application of the service-oriented architectural style in the context of industrial enterprises. This style provides a commonly perceived paradigm for organizing distributed software systems. However, beyond general attention to this style, there are only few descriptions of the difference between service orientation and more mature styles, such as component orientation. This dissertation argues that the service-oriented style is an approach that centralizes control over distributed functionality that is provided by the application systems of an organization. This means that service orientation is a paradigm for application integration. Moreover, we argue that it is not possible to fully formalize the inherent principles of service orientation as part of an architectural style description. In fact, soft design principles are a differentiator of this style. These principles, however, are rarely applied in the context of industrial enterprises. This is why we analyze how such design principles could be objectively described and what attention should be paid to them. This analysis is performed by categorizing the potential benefits of this style and assigning the respective underlying principles to the identified benefits. Subsequently, a reference architecture is defined on the basis of these findings. This architecture focuses on structuring service-oriented applications - so-called composite applications. In order to apply the defined reference architecture in the context of actual projects, we describe a design methodology for composite applications. This design methodology focuses on using business processes for designing various types of services and on describing their interconnections by the reference architecture. To achieve this, a service design algorithm is included that derives services from business processes by incorporating the results of a statistical analysis of service design principles. The result of this methodology is a platform-independent design of a composite application. It considers the restrictions of the application landscape in which a composite will be deployed. To permit the realization of composite applications, we informally map the platform-independent reference architecture to a platform that is widely used in industrial enterprises. This mapping is, together with the design methodology and the reference architecture, applied to an industry-scale use case. This way, the applicability of the concepts is demonstrated.
Recently, service orientation has strongly influenced the way enterprise applications are built. Service ecosystems, which provide means to trade services between companies like goods, are an evaluation of service orientation. To allow service ordering, discovering, selection, and consumption, a common way to describe services is a necessity. This paper discusses existing approaches to describe certain service aspects. Finally, a Service Description Framework for service ecosystems is proposed and exemplified.
The present work analyses decision making behaviour in personnel selection. The analysis focuses on the investigation of the relative importance of particular characteristics of the applicant on his or her hirability (applicant competencies, person-organisation and person-job fit, and social capital). Furthermore, it is analysed how firm size and age moderate this relative importance and in how far decision makers possess insight into their own decision making behaviour. The work is structured as follows: In the first chapter, the research topic is introduced, its importance and research gaps are described and the research approach is laid out. Furthermore, a literature review (chapter 2) provides a brief overview of the literature written on staffing in small and / or emerging firms. In chapter 3, I will elaborate that personnel selection is basically a decision making process with three major components: decision cues, criteria, and predictors. The description of selection theory with the interaction of criteria and predictors in the process of predicting future job performance of the applicant as well as a brief overview of selection practices with a vast number of potential decision cues leads to the next chapter. Chapter 4 presents an excursus in this thesis. As the findings of the previous chapter created a particular tension between theory and practice, an empirical pilot investigation was conducted to close that gap and to reconcile both theory and practice. Five case studies in emerging German IT and high-tech companies shed light on the elements to focus on in further research. These case studies also help to reconcile the theory of personnel selection with the special aspects of selection in the IT-context which is the particular focus industry of this thesis. In chapter 5, I continue with laying out the theory of personnel selection and close the theoretical part. I analyse the role and impact of three sets of decision cues: applicant competencies, applicant-organisation fit and applicant networks. This chapter is closed with the generation of a number of hypotheses on the use and importance of these decision cues in personnel selection in emerging high-technology firms. The third part of this thesis describes the empirical research undertaken to further investigate decision making in selection situations and to test the hypotheses. Chapter 6 introduces conjoint analysis as an appropriate means to capture decision policies and to answer the research questions. Variables, research instrument, and research approach are presented. The results of the described experimental survey are laid out in the following chapter 7. After the sample has been described, the data collected is analysed and presented and the hypotheses are tested. The fourth and final part of this thesis comprises the conclusion. In the last chapter, the results are discussed in the light of the previously laid out theory. Both limitations of the study as well as hints for future research are presented.
Business Process Management Systems (BPMS) aim to support the Business Process Management paradigm and to ease legacy application integration. Often, they rely on Service-oriented Architecture (SoA). However, do such systems really meet real-world requirements? This paper introduces and discusses a set of criteria which are important for BPMS and applies these criteria in comparing tools from three important vendors, namely IDS Scheer, Oracle and Intalio based on a case study.
In spite of the Malay Archipelago’s location at the crossroads of the maritime spice route which allowed the reception of ideas and influences from China, the Middle East, and Europe, Javanese mosques and shrines are widely believed, by local Indonesian and international scholars, to originate from earlier local Hindu-Buddhist predecessors. Variations of local buildings such as temples, cock-fight arenas, communal buildings, and vernacular houses have been suggested as the prototype on which the masjid was modelled. The mausoleums were linked to earlier mountain sites and Hindu-Buddhist practices of veneration of the dead. Two scholars, however, de Graaf and Slametmuljana, contested the dominant perception and suggested a foreign origin for the Javanese mosque; the former, on basis of similarities in the use of timber as the construction medium, suggested the western Coast of India and the latter on basis of reports in a local Javanese history which records the visit of the Chinese Zheng He to a mosque in Java in the early 15th century, proposed China as the source for the earliest Javanese masjid. This dissertation addresses the issue of the origin of the Javanese Islamic buildings (mosques and shrines) by means of an architectural approach. Architecture, as suggested by Hillenbrand, being a combination of form, function, and meaning, the approach used here, therefore, looks beyond the external features of the buildings and into the embedded ideas in order to inspect whether the mosque concept, plan, orientation, functions, and construction, or any of its given cosmic associations relied on contemporary or older local or foreign beliefs. Not only are the mosques concerned here, but the shrines as well. The dissertation is divided into four chapters. The first is a broad historical introduction that gives an overall picture of he Malay Archipelago from the 3rd century A. D. onwards when the Indians arrived at the islands till the 16th century when the Portuguese established their hegemony in the region. Theories regarding the arrival of Islam and the foundation of Muslim polities in Sumatra, the Malay Peninsula and Java and the “Islamization” of the Spice Islands are addressed in more detail. The second chapter is a descriptive and pictorial catalogue of the monuments concerned, i.e., 15th and 16th centuries mosques and shrines of the northern coast of Java. Mosques selected are those of Demak, Banten, Cirebon and the Masjid Panjunan in Cirebon. The shrines are those of Drajat, Gunung Jati, Ratu Kalinyamat, Sendang Duwur, Bonang, and Kudus. The third chapter is an analytical comparison between the architecture of local buildings, their associated iconography and religious beliefs, architectural details, and decorations and those of the Javanese mosque and shrine. The aim is to assess whether the Javanese mosque and shrine are products of the local architecture. The fourth chapter questions the theories on China and India as possible sources for the origin of Javanese Islamic buildings and hypothetically reconstructs the Javanese mosque design process in an attempt to unveil the source of the mosque’s architectural concept. The chapter concludes by evaluating the role of the Arab merchant in the design and construction of the Javanese mosque and shrine.