The 20 most recently published documents
Der souveräne Umgang mit der SPSS Syntax bietet einen unschätzbaren Vorteil für die tägliche Arbeit von Anwendern, die mit der Analyse von Daten zu tun haben. Das Buch ist eine integrierte Einführung in die Steuersprache von IBM SPSS Statistics für Studenten, Forscher und Praktiker. Es behandelt neben den notwendigen Grundlagen die Themengebiete Datenaufbereitung, Datentransformation und -modifikation. Weitere Themengebiete umfassen die Makro- und Matrixsprache, die in der 2. Auflage deutlich erweitert worden sind.
Die Steigerung der Energieeffizienz ist eine gesellschaftliche Notwendigkeit und bildet neben dem Umstieg auf erneuerbare Energien den entscheidenden Hebel zur Realisierung der Energiewende und Minderung der CO2-Emissionen in Deutschland. Kleine und mittlere Unternehmen (KMU) nehmen in diesem Zusammenhang eine besondere Stellung ein: Aktuelle Studien deuten auf geringere Steigerungsraten der Energieeffizienz gegenüber Großunternehmen hin, die zumeist mit unterschiedlichen materiellen und personalen Voraussetzungen erklärt werden.
Das Forschungsprojekt "Entscheidungen für Energieeffizienz" widmete sich vor diesem Hintergrund der Situation produzierender KMU in Baden-Württemberg. Mit dem Ziel, ein verbessertes Verständnis über die Energieeffizienz-Entscheidungen der KMU zu gewinnen, wurde der Frage nachgegangen, wie der Umgang mit Energie in der täglichen Praxis in KMU organisiert wird, wie über Energieeffizienz entschieden wird und welche Treiber und Hemmnisse sich dabei ergeben.
Zur Beantwortung der Fragen wurde ein Ansatz verfolgt, der kulturelle Einflüsse mitberücksichtigt. Forschungsstrategisch kam ein Mixed-Methods-Ansatz zur Anwendung, der durch die Kombination von qualitativen Daten (Einzelfallstudien) und quantitativen Daten (Fragebogenerhebung) methodisch umgesetzt wurde.
Durch die Differenzierung der Produkte nach verschiedenen Kundengruppen konnte das Unternehmen seinen Marktanteil trotz des gesättigten Markts ausbauen. Neben der erstklassigen Qualtät seiner Produkte unterscheidet das Unternehmen sich nun auch noch durch seine kundengruppenspezifische Entwicklung und Vermarktung von der No-Name-Konkurrenz und den Herstellern aus Niedriglohnländern. Diese Sicherung der Marktposition wiegt die Kosten der notwendigen Flexibilisierung mehr als auf. Das Unternehmen ist durch seine neuen und innovativen Produkte besser für die Zukunft gerüstet. Es kann durch seine hervorragenden Kontakte zu seinen Kunden auf die sich ändernden Wünsche und Anforderungen seiner vielfältigen Kundschaft schnell und gezielt reagieren.
Der vorliegende Beitrag zeigte die Anwendung eines Extended Kalman Filters für die Beurteilung des Verschleißzustandes von Rollenketten. Anders als in den üblicherweise eingesetzten signalbasierten Verfahren wurde damit ein modellbasierter Ansatz gewählt. Der Einsatz des Extended Kalman Filters ermöglicht die Schätzung von Parametern eines reduzierten Kettenmodells, das die Dynamik der einzigen Messgröße, nämlich des Drehmoments des antreibenden Motors näherungsweise nachbildet. Im Beitrag wurde dieses Verfahren auf Messdaten aus vier Dauerversuchen an Rollenketten eingesetzt und gezeigt, dass mit steigendem Verschleiß eine Änderung ausgewählter Modellparameter erfolgt.
Diese Vorgehensweise ist ein erster Ansatz, der durch weitere Forschungsarbeiten noch verbessert werden muss. In zukünftigen Forschungsarbeiten wird zusätzlich zur Parameterschätzung eine Prädiktion durchgeführt, um einen Schätzwert für die Restlebensdauer zu erhalten. Hierzu gibt es Ansätze in der Literatur, die auf das konkrete Problem angepasst werden müssen. Zudem muss die Modellierungssystematik so erweitert werden, dass Wissen über das Prozessverhalten in die Modellierung mit eingebracht wird, um die Aussagekraft der Ergebnisse sowie die Robustheit des Verfahrens bezüglich Betriebsparametern, Umgebungsbedingungen und Exemplarstreuungen zu verbessern.
In order to be innovative, an organisation has to utilise the skills of all its employees. Implementing the potential of women, older staff members as well as people with different backgrounds leads to more creative ideas, new approaches and results in more innovative products. But how can a company use the innovative potential of its diverse workforce? And how can customer diversity be used to create innovations?
This book answers these questions as well as many more related to the topic of diversity management and innovation. Special emphasis is put on the role of women in the innovation system. Therefore, the language and effects of pictures used in job advertisements are addressed. Moreover, measures to advocate highly innovative women are identified including their demands regarding workplace requirements.
In addition, the book deals with diversity management in both publicly traded companies and public institutions. The involvement of children as Lead Users along the product development process is addressed as well. Given the fact that innovation does not only comprise products, but also services, a separate chapter focusing on the effect of Diversity on service innovations is included.
Sole value – the sneaker resale market :
an explorative analysis of the sneaker resale market
(2018)
The purpose of this explorative research paper is to examine the sneaker resale market and its typical processes in order to give a comprehensive overview over the secondary market for limited edition sneakers. Hypotheses are presented that will be analysed with the empirical research methods of expert interviews and sales data analysis. Amongst other findings, this paper shows that there is a complementary relationship between sneaker brands and the resale market; that product limitation is essential for value increases; that collaborations are necessary for sneaker brands to be relevant on the resale market and that the market is very fragmented. All combined circumstances described in this paper explain the sneaker resale market and its processes. Additionally, some outlooks on the future will be given with the help of expert interviewees and current developments on the market will be discussed.
Customer relationship management (CRM) is one of the most frequently adopted management tools and has received much attention in the literature. From a company-wide perspective, CRM is viewed as a complex process requiring interventions in different company areas. Previous research has already highlighted the pitfalls and failures related to a partial and incomplete view of CRM. This study advances research on CRM by investigating the impact of the relative implementation time according to which interventions are implemented in different areas (customer management, CRM technology, organizational alignment, and CRM strategy) on CRM performance. The results of the empirical study reveal that compared to other critical CRM activities, a later implementation of organizational alignment activities has a negative impact on performance. Further, our results show that CRM implementations do not equally address the areas of customer acquisition, growth, and loyalty, since this clearly depends on company objectives and also on geographical differences.
Drei Stufen geben Sicherheit
(2018)
GaN-Transistoren bieten ein enormes Potenzial für kompakte Leistungselektronik, indem sie die Größe von passiven Bauelementen verringern. Allerdings bringt das schnelle Schalten Herausforderungen für den Gate-Treiber mit sich. Ein vollständig integrierter Treiber mit drei Spannungsstufen hilft, diese zu lösen.
The level shifter and the floating gate supply for high-side transistors are a major challenge in high-voltage DCDC converters. This paper presents a high speed and power-efficient level shifter for voltages of up to 50V, suitable for both PMOS and NMOS power FETs. A switching node falling edge detection allows both, a sensitive and safe signal detection. This enables a robust operation during steep dv / dt transitions and a power consumption as low as 4.1 pJ per switching cycle, which is a reduction of more than 40% compared to prior art. An active clamping circuit prevents common mode displacement currents into the high-side supply. The level shifter is implemented in a 180nm BiCMOS technology. Measurements confirm a 50V 120MHz high-speed operation of the level shifter with a rising / falling propagation delay of 1.45 ns / 1.3 ns, respectively. The dv / dt robustness has been confirmed by measurements for transitions up to 6V/ ns.
A wide-bandwidth galvanically isolated current sensing circuit with an integrated Rogowski coil in 180nm CMOS is presented. Exploiting the high-frequency properties of an optimized on-chip Rogowski coil, currents can be measured up to a bandwidth of 75 MHz. The analog sensor front-end comprises a two-stage integrator, which allows a chopper frequency below signal bandwidth, resulting in 2.2 mVrms output noise. An additional integrated Hall sensor extends the measurement range towards DC.
Due to their superior fast-switching performance, GaN transistors show enormous potential to enable compact power electronics in applications like renewable energy, electrical cars and home appliances by shrinking down the size of passives. However, fast switching poses challenges for the gate driver. Since GaN transistors have a low threshold voltage Vt of ~1V, an unintended driver turn-on can occur in case of a unipolar gate control as shown for a typical half-bridge in Fig. 24.2.1 (top left). This is due to coupling via the gate-drain capacitance (Miller coupling), when the low-side driver turns on, causing a peak current into the gate. This is usually tackled by applying a negative gate voltage to enhance the safety margin towards Vt, resulting in a bipolar gate-driving scheme. In many power-electronics applications GaN transistors operate in reverse conduction, carrying the inductor current during the dead time t, when the high-side and low-side switch are off (as illustrated at a high-side switch in Fig. 24.2.1, bottom left). As there is no real body diode as in silicon devices, the GaN transistor turns on in reverse operation with a voltage drop VF across the drain-source terminals (quasi-body diode behavior). As a negative gate voltage adds to VF, 63% higher reverse-conduction losses were measured for a typical GaN switch in bipolar gate-drive operation. This drawback is addressed by a three-level gate voltage (positive, 0V, negative), which at the same time provides robustness against unintended turn-on similar to the bipolar gate driver, proven in [1] for a discrete driver.
This paper presents a fully integrated gate driver in a 180-nm bipolar CMOS DMOS (BCD) technology with 1.5-A max. gate current, suitable for normally OFF gallium nitride (GaN) power switches, including gate-injection transistors (GIT). Full-bridge driver architecture provides a bipolar and three-level gate drive voltage for a robust and efficient GaN switching. The concept of high voltage energy storing (HVES), which comprises an on-chip resonant LC tank, enables a very area-efficient buffer capacitor integration and superior gatedriving speed. It reduces the component count and the influence of parasitic gate-loop inductance. Theory and calculations confirm the benefits of HVES compared to other capacitor implementation methods. The proposed gate driver delivers a gate charge of up to 11.6 nC, sufficient to drive most types of currently available GaN power transistors. Consequently, HVES enables to utilize the fast switching capabilities of GaN for advanced and compact power electronics.
In current times, a lot of new business opportunities appeared using the potential of the Internet and related digital technologies, like Internet of Things, services computing, cloud computing, big data with analytics, mobile systems, collaboration networks, and cyber physical systems. Enterprises are presently transforming their strategy, culture, processes, and their information systems to become more digital. The digital transformation deeply disrupts existing enterprises and economies. Digitization fosters the development of IT environments with many rather small and distributed structures, like Internet of Things. This has a strong impact for architecting digital services and products. The change from a closed-world modeling perspective to more flexible open-world and living software and system architectures defines the moving context for adaptable and evolutionary software approaches, which are essential to enable the digital transformation. In this paper, we are putting a spotlight to service oriented software evolution to support the digital transformation with micro granular digital architectures for digital services and products.
While there are several theoretical comparisons of Object Orientation (OO) and Service Orientation (SO), little empirical research on the maintainability of the two paradigms exists. To provide support for a generalizable comparison, we conducted a study with four related parts. Two functionally equivalent systems (one OO and one SO version) were analyzed with coupling and cohesion metrics as well as via a controlled experiment, where participants had to extend the systems. We also conducted a survey with 32 software professionals and interviewed 8 industry experts on the topic. Results indicate that the SO version of our system possesses a higher degree of cohesion, a lower degree of coupling, and could be extended faster. Survey and interview results suggest that industry sees systems built with SO as more loosely coupled, modifiable, and reusable. OO systems, however, were described as less complex and easier to test.
While the recently emerged microservices architectural style is widely discussed in literature, it is difficult to find clear guidance on the process of refactoring legacy applications. The importance of the topic is underpinned by high costs and effort of a refactoring process which has several other implications, e.g. overall processes (DevOps) and team structure. Software architects facing this challenge are in need of selecting an appropriate strategy and refactoring technique. One of the most discussed aspects in this context is finding the right service granularity to fully leverage the advantages of a microservices architecture. This study first discusses the notion of architectural refactoring and subsequently compares 10 existing refactoring approaches recently proposed in academic literature. The approaches are classified by the underlying decomposition technique and visually presented in the form of a decision guide for quick reference. The review yielded a variety of strategies to break down a monolithic application into independent services. With one exception, most approaches are only applicable under certain conditions. Further concerns are the significant amount of input data some approaches require as well as limited or prototypical tool support.
Based on a survey among customers of seven German municipal utilities, we estimate hierarchical multiple regression models to identify consumer motivations for participating in P2P electricity trading and develop implications for marketing strategies for this currently relatively unknown product. Our results show a low importance of socio-demographics in explaining differences between consumer groups, but high influence of attitudes, knowledge and likelihood to purchase related products. The most valuable target groups for P2P electricity trading marketing strategies of municipal utilities first and foremost should aim at are innovators, especially prosumers. They are well-informed about and open minded concerning electricity sharing and highly environmentally aware. They ask for transparency and are willing to purchase related products. They are attracted by the ability to share generation and consumption and to a lesser extent by economic reasons. Our results indicate that the marketing efforts should to a special degree take peer effects into account, as they are found to wield great influence on general openness towards and purchase intention for P2P electricity products. Finally, municipal utilities should build on the high level of satisfaction and trust of consumers and use P2P electricity trading as measure to keep and win customers willing to change their supplier.
The sound of brands
(2019)
The aim of this research paper is to both examine and conceptualise the concept of audio branding. Audio branding is an important part of the overall brand management concept and corporate identity. Strong brands ease the choice for customers and convey values and a certain quality promise. Branding is of vital importance. It needs to be acknowledged that only 0.004% of all outer stimuli reach the human consciousness. Therefore, audio branding is a way to further strengthen the overall brand awareness. This leads to an emotional connection with a brand.
This study strives to determine the characteristics of audio branding and to analyse the corporate audio branding of Audi. The result of this research study is the suggestion of the use of audio branding in a way that fits the overall brand picture. Otherwise, the brand communication is inconsistent, and this could lead to a misunderstanding of the brand values for customers. The analysis of the Audi corporate sound design might be beneficial for practitioners. The overall evaluation of the concept of audio branding contributes to the existing body of literature in branding.
The promise of immutable documents to make it easier and less expensive for consumers and producers to collaborate in a verifiable way would represent an enormous progress, especially as companies strive for establish service contracts which are based on the flow of many small transactions using machine-to-machine communication. The blockchain technology logs these data, verifies the authenticity and make them available for service offers. This work deals with an architecture enabling to setup order processing between consumers and produceers using blockchain. In this way, the technical feasibility is shown and the special characteristics of blockchain production networks will be discussed.
Im Anschluss an eine theoretisch fundierte und zugleich praxisnahe und umfassende Darstellung des gesamten Event-Marketing und -Management untersucht Gerd Nufer die bislang noch wenig erforschte Wirkungsweise des innovativen Kommunikationsinstruments und geht dabei vertiefend auf das Zustandekommen eines Imagetransfers von einem Event auf eine Marke bzw. ein Unternehmen ein. Abschließend werden dauerhafte Markenerlebniswelten als aktuelle Weiterentwicklungen des Event Marketing vorgestellt. Das Buch bietet eine theoretisch fundierte und zugleich praxisnahe, umfassende Darstellung zum gesamten Event-Marketing und -Management. Darüber hinaus untersucht Gerd Nufer die bislang noch wenig erforschte Wirkungsweise des innovativen Kommunikationsinstruments und geht dabei vertiefend auf das Zustandekommen eines Imagetransfers von einem Event auf eine Marke bzw. ein Unternehmen ein. Abschließend werden dauerhafte Markenerlebniswelten als aktuelle Weiterentwicklungen des Event-Marketing vorgestellt.
Purpose of the research paper is to illuminate the subject of assortment policy in the German fashion e‐commerce market. A short literature review is conducted in order to set up a system of characteristics to contemplate assortments on a strategic level. In a second step, structured observations are conducted to quantitatively analyze and compare the assortments of the leading online fashion retailers within Germany. Based on literature, the following characteristics for a classification of assortments can be identified: assortment structure, assortment size, assortment width, assortment depth, assortment consistency and rotation, price level, quality mix, fashion degree as well as the mix of private labels and manufacturer brands. Furthermore, the results of the empirical analysis show that there are currently five leaders within the nalyzed market: Amazon, Otto, Zalando, Baur and About You. Among these five market leaders, Amazon positions itself as a retailer that not only offers an enormous assortment size, but also the lowest entry prices as well as the broadest price dispersion. Through the development of the system of characteristics for assortment analysis and the examination of the current market environment, the findings of this paper contribute to the current state of the art in both theoretical and practical aspects.
