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Usable security puts the users into the center of cyber security developments. Software developers are a very specific user group in this respect, since their points of contact with security are application programming interfaces (APIs). In contrast to APIs providing functionalities of other domains than security, security APIs are not approachable by habitual means. Learning by doing exploration exercises is not well supported. Reasons for this range from missing documentation, tutorials and examples to lacking tools and impenetrable APIs, that makes this complex matter accessible. In this paper we study what abstraction level of security APIs is more suitable to meet common developers’ needs and expectations. For this purpose, we firstly define the term security API. Following this definition, we introduce a classification of security APIs according to their abstraction level. We then adopted this classification in two studies. In one we gathered the current coverage of the distinct classes by the standard set of security functionality provided by popular software development kits. The other study has been an online questionnaire in which we asked 55 software developers about their experiences and opinion in respect of integrating security mechanisms into their coding projects. Our findings emphasize that the right abstraction level of a security API is one important aspect to consider in usable security API design that has not been addressed much so far.
Solar energy is one option to serve the rising global energy demand with low environmental impact. Building an energy system with a considerable share of solar power requires long-term investment and a careful investigation of potential sites. Therefore, understanding the impacts from varying regionally and locally determined meteorological conditions on solar energy production will influence energy yield projections.
Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic (PV) systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data.
This paper presents the b-it-bots RoboCup@Work team and its current hardware and functional architecture for the KUKA youBot robot. We describe the underlying software framework and the developed capabilities required for operating in industrial environments including features such as reliable and precise navigation, flexible manipulation and robust object recognition.
An Experimental Field-Study on Active and Passive Work Breaks in a Stressful Work Environment
(2017)
Work breaks are known to have positive effects on employees’ health, performance, and safety. However, prior research has focused mainly on their timing, duration, and frequency but less on break activities. Moreover, most studies examined work breaks in rather repetitive and physical demanding work. Thus, we conducted an experimental field study with a sample of employees’ working in a stressful and cognitive demanding working environment and examined how different types of work breaks (boxing, deep relaxation, and usual breaks) affect participants’ mood, cognitive performance, and neuro-physiological state.
This paper proposes a novel approach to the generation of state equations from a bond graph (BG) of a mode switching linear time invariant model. Fast state transitions are modelled by ideal or non-ideal switches. Fixed causalities are assigned following the Standard Causality Assignment Procedure such that the number of storage elements in integral causality is maximised. A system of differential and algebraic equations (DAEs) is derived from the BG that holds for all system modes. It is distinguished between storage elements with mode independent causality and those that change causality due to switch state changes.
Neben der Verbesserung des Gesundheitszustandes sind der Erhalt der Beschäftigungsfähigkeit und die berufliche (Wieder-)Eingliederung zentrale Ziele der Rehabilitationsleistungen der Deutschen Rentenversicherung. In der „Reha-QM-Outcome-Studie“ wurden sowohl mittels Patientenfragebogen Angaben zum subjektiven Nutzen der Behandlung als auch mittels Routinedaten der Rentenversicherung Angaben zum Erwerbsstatus bzw. zur Berentung erhoben, so dass eine Gegenüberstellung beider Zieldimensionen erfolgen kann.
Wo Laborexperimente zu aufwendig, zu teuer, zu langsam oder zu gefährlich oder Stoffeigenschaften gar nicht erst experimentell zugänglich sind, können Computersimulationen von Atomen und Molekülen diese ersetzen oder ergänzen. Sie ermöglichen dadurch Reduktion von Kosten, Entwicklungszeit und Materialeinsatz. Die für diese Simulationen benötigten Molekülmodelle beinhalten zahlreiche Parameter, die der Simulant einstellen oder auswählen muss. Eine passende Parametrierung ist nur bei entsprechenden Kenntnissen über die Auswirkungen der Parameter auf die zu berechnenden Größen und Eigenschaften möglich. Eine Gruppe von Standardparametern in molekularen Simulationen sind die Partialladungen der einzelnen Atome innerhalb eines Moleküls. Die räumliche Ladungsverteilung innerhalb des Moleküls wird durch Punktladungen auf den Atomzentren angenähert. Für diese Annäherung existieren diverse Ansätze für verschiedene Molekülklassen und Anwendungen. In diesem Teilprojekt des Promotionsvorhabens wurde systematisch der Einfluss der Wahl des Partialladungssatzes auf potentielle Energien und ausgewählte makroskopische Eigenschaften aus Molekulardynamik-Simulationen evaluiert. Es konnte gezeigt werden, dass insbesondere bei stark polaren Molekülen die Auswahl des geeigneten Partialladungssatzes entscheidenden Einfluss auf die Simulationsergebnisse hat und daher nicht naiv, sondern nur ganz gezielt getroffen werden darf.
In diesem Artikel wird darüber berichtet, ob die Glaubwürdigkeit von Avataren als mögliches Modulationskriterium für die virtuelle Expositionstherapie von Agoraphobie in Frage kommt. Dafür werden mehrere Glaubwürdigkeitsstufen für Avatare, die hypothetisch einen Einfluss auf die virtuelle Expositionstherapie von Agoraphobie haben könnten sowie ein potentielles Expositionsszenario entwickelt. Die Arbeit kann innerhalb einer Studie einen signifikanten Einfluss der Glaubwürdigkeitsstufen auf Präsenz, Kopräsenz und Realismus aufzeigen.
Die Detektion von Explosivstoffen stellt ein zentrales Feld der zivilen Sicherheitsforschung dar. Eine besondere Herausforderung liegt hierbei in dem Nachweis verpackter Substanzen, wie es bei Unkonventionellen Spreng- und Brandvorrichtung (USBV) häufig der Fall ist. Derzeit eingesetzte Verfahren arbeiten meist mit bildgebenden Techniken, durch die sich ein Anfangsverdacht ergibt. Der tatsächliche chemische Inhalt der USBV lässt sich jedoch nicht exakt ermitteln. Eine genaue Beurteilung der Gefährdung durch solche Substanzen ist allerdings von großer Bedeutung, insbesondere wenn die Entschärfung des Objekts in bewohntem Gebiet stattfinden muss. In der vorliegenden Arbeit wird ein Verfahren vorgestellt, das sich als Verifikationsverfahren bei bestehendem Anfangsverdacht gezielt einsetzen lässt. Hierzu wird mittels Laserbohrtechnik zunächst die äußere Hülle des zu untersuchenden Gegenstandes durchdrungen. Anschließend finden eine lasergestützte Probenahme des Inhalts sowie die Detektion unter Verwendung geeigneter Analysemöglichkeiten statt. Der Bohr- und Probenahmefortschritt wird über verschiedene spektroskopische und sensorische Verfahren begleitend überwacht. Zukünftig soll das System abstandsfähig auf Entschärfungsrobotern eingesetzt werden.
Raman-microspectroscopy was used for the non-destructive characterization and differentiation of six different meat spoilage associated microorganisms, namely Brochothrix thermosphacta DSM 20171, Micrococcus luteus, Pseudomonas fluorescens DSM 4358, Escherichia coli Top10 and K12 and Pseudomonas fluorescens DSM 50090. To evaluate and classify the Raman-spectroscopic data at species and strain level an adequate preprocessing and subsequent principal component analysis was used. The same procedure was extended to an independent test data set, which could be successfully assigned to the correct bacterial species and even to the right strain. The evaluation was not only successful in differentiation of gram-positive and gram-negative bacteria but also the discrimination between the different bacterial species and strains was possible. This means that the training data set, the preprocessing method and the evaluation of the data lead to a robust principal component analysis. Even the correct assignment of unknown samples is possible. The results show that Raman-microspectroscopy in combination with an appropriate chemometric treatment can be a good tool for a rapid examination and classification of microbial cultures.
Ressourceneffiziente Optimierung von Hohlkörpern aus Kunststoff mittels Multiskalensimulation
(2017)
Die mechanischen Eigenschaften von extrusionsblasgeformten Kunststoffhohlkörpern hängen wesentlich von den vom Verarbeitungsprozess beeinflussten Materialeigenschaften ab. Ziel der dargestellten Untersuchung ist, prozessabhängige Materialkennwerte in Simulationsprogrammen zu berücksichtigen und damit deren Vorhersagegenauigkeit zu erhöhen. Hierzu ist die Schaffung einer Schnittstelle zwischen Prozess- und Bauteilsimulation notwendig. Darüber hinaus wird vorgestellt, wie Simulationen auf Mikroebene (molekulardynamische Simulationen) genutzt werden können, um Materialkennwerte ohne die Durchführung eines Realexperiments zu ermitteln.
Traditionally automotive UI focusses on the ergonomic design of controls and the user experience in the car. Bringing networked sensors into the car, connected cars can provide additional information to car drivers and owners, for and beyond the driving task. While there already are technological solutions, such as mobile applications commercially available, research on users’ information demands in such applications is scarce. We conducted four focus groups to uncover what kind of information users might be interested in to see on a second dashboard. Our findings show that besides control screens of todays’ dashboards, people are also interested in connected car services providing context information for a current driving situation and allowing strategic planning of driving safety or supporting car management when not driving. Our use cases inform the design of content for secondary dashboards for and especially beyond the driving context with a user perspective.
Climate change is having drastic effects on various areas of the planet, including extreme impacts on weather and rainfall, in various Sub-Saharan East African countries (Hendrix, C. S., & Glaser, S. M. (2007). The willingness (and need) of a niche market to actively improve the damaged ecosystems in small ways is rising. Weaver and Lawton (2007, p 1170) maintain that ecotourism should satisfy three core criteria: "(1) attractions should be predominantly nature-based; (2) visitor interactions with those attractions should be focused on learning or education, and (3) experience and product management should follow principles and practices associated with ecological, socio-cultural and economic sustainability." In this study, the niche market of active German "tree-planters" is to be defined and the potential willingness to travel to, learn from and invest in the ecosystem through tree-planting, specifically in Kenya, is explored.
“Building Bridges Across Continents” (BBAC) is an intercultural and student-centered project that seeks to promote international communication and helps students develop competencies in entrepreneurship, international trade and global cultural awareness. The project, which is in its fourth phase of implementation, connects students from the United States, Germany, Ghana and Kenya with the help of Information Communication Technologies (ICT) in order to work on a common research assignment for a period of ten calendar weeks. The main ICTs used in the project are Skype, Facebook, wiki, email and WhatsApp. This paper describes and analyzes the background, structure, and results of the project.
This study sought to contribute to knowledge by assessing the moderating effect of industry forces on the relationship between linkage strategies and performance of universities in Kenya. Porter’s five forces model and Resource Based View (RBV) are the main theories anchoring the study. Cross-Sectional survey was adopted as the research design. The population of the study consists of sixtyfive (65) public and private universities incorporated in Kenya. Out of this, a sample of forty seven (47) universities which had undergone at least one graduation cycle was taken. Primary and secondary data was collected using semi-structured questionnaires and review of existing university documents and regulatory bodies websites respectively. The instrument was tested for reliability and found fit. Analysis was undertaken using correlation and regression analyses to test hypotheses. Analysis of variance was also used to determine the differences between group means. Coefficient of variation (C.V) was also used to measure variability and consistency in scores of different universities when standard deviation and arithmetic means are compared. Out of the targeted forty seven (47) respondents from forty seven (47) universities, a total of forty four (44) questionnaires were returned, representing 94% response rate. It was established that there is a moderating effect of industry forces on the relationship between linkage strategies and organizational performance. The results provided rich implications for theory, policy and practice. The significance of industry forces in strategy formulation and implementation requires concentrated attention. The findings offer insights to university authorities and policy makers by answering the question on the influence of industry forces on performance of higher learning institutions. The key recommendation that the study offers to the stakeholders, is the need to consider industry forces as critical determinants during strategy formulation and implementation process in order to enhance university performance. The main limitation of this study is that primary data was collected from only one respondent per university but common methods bias was mitigated through the use of additional secondary data to validate primary data. Thus, the limitation did not affect the credence of the results as presented and discussed. Secondly, although it was not possible to include all the determinants of institutional performance, balanced score card was appropriately used to represent financial and non-financial aspects that constitute performance indicators.
Entrepreneurship Development and New Business Challenges and Prospects for Ghanaian Entrepreneurs’
(2017)
This paper presents a framework for formulating strategies for business start-ups within the context of small and medium-scale enterprises (SMEs) in diverse industries. Using Ghana as a case study, it addresses how to increase entrepreneurs’ success rate in business ventures in developing countries. The objective of the study is to identify avenues through which entrepreneurs could address the challenges they face, and to take advantage of the emerging opportunities in the domestic and global business environments. The questions addressed are, what challenges face Ghanaian entrepreneurs’ new business start-ups and existing SME’s in developing countries? How could these challenges be addressed appropriately to make the private sector the engine of growth in Ghana’s economy? The methodology is based on the qualitative approach, involving interviews to achieve the study’s objectives. Four main themes emerged as challenges faced by the entrepreneurs business start-ups and operations which include the following: Funding availability & accessibility; Lack of planning, Skilled labour & proper management skills; Lack of competitiveness, technology innovation & customer loyalty; and finally, Legal & regulatory framework & social factors. Recommendations for entrepreneurs, policy makers, and scholars are discussed in the study.
Examining the Effect of Corruption and Bureaucracy on SMEs Growth in the Kumasi Metropolis of Ghana
(2017)
Small and Medium Enterprises (SMEs) are considered a seed-bed of entrepreneurship and innovation in most emerging economies; nevertheless, SMEs sometimes lack an enabling business climate, which hinders their potential growth. This paper examines the effect of corruption and bureaucracy on SMEs growth in the Kumasi Metropolis of Ghana. The study was a quantitative research, and convenience sampling method was employed to select 373 owners/managers as respondents for the study. Employing questionnaire as its main data collection instrument, the study used Gretl version 3.0 Statistical Software for the analysis of data collected. The results of the study revealed that 1% increase in corruption in the SMEs sector leads to 36.12% decline in SMEs growth (sales and employment), and 1% increase in bureaucracy leads to 28.76% decrease in the growth of SMEs. An interesting outcome of the study was that the excessive bureaucratic bottlenecks in the SMEs sector are implied by corruption. We, therefore, conclude that there is a significant negative relationship between corruption and bureaucracy and SMEs growth. It is, therefore, recommended that the government takes a giant-step to fight corruption in the SMEs sector by ensuring transparency and accountability of public officials and also streamline its systems and activities in the sector to reduce the excessive administrative barriers. The present study adds substantial value to the body of research on SMEs as it is the first research to have considered the joint effect of corruption and bureaucracy on SMEs growth in an emerging economy like Ghana.
Gender disproportions have been part and parcel of most African cultures since time immemorial. Demographically, women are over a half population in most of the African countries but their participation in sectors of socio-economic and political spheres have remained inadequately represented. The enduring and biased beliefs on gender roles that view women much less important as compared to men are what forms the basis of concern to the welfare of women and most importantly the women entrepreneurs. This study reveals the long-standing cultural practices that have contributed to gender inequality and goes further to demystify areas in which women have continually experienced inequality and thus affecting their entrepreneurial spirit. Through the desk research methodology, it can be deduced that the following are key areas that pause a threat to women socio-economic and political development and hence the inequality being experienced even today in the twenty first century: harmful marriage, female genital mutilation, wife inheritance and HIV scourge, access to land including land rights and right to property, over-emphasizing patriarchal system of family, and gender violence. These factors compounded together, have resulted for unfortunate experiences that have been witnessed in the education sector, political participation, participation in policy making, gender division of labour and inaccess to credit facility. These experiences have severely thwarted entrepreneurial growth of women. The study therefore recommends that there is imperative need for a paradigm shift in these areas to ensure women are not only liberated and empowered but also their full participation in the entrepreneurship activities are highly strengthened and promoted.
In Africa slowly but steadily a transformation is taking place in the management styles of enterprises. There is a trend towards more precise time management, more precision in dealing with increasingly sophisticated technology, more feedback from the bottom to the top in order to manage the processes properly, more professionalism and independence of the individual worker.
This contribution makes two points: first, neither cultures nor the so-called mental states of individuals are ever static, but always on the move. Second, the force of passion and inspiration by which particular cultural values are endorsed in a particular context makes all the difference in their impact.
The importance of these two propositions comes to the fore, if the concept of an “economic culture” is taken into consideration. The claim of the authors is that the ongoing cultural transformation can be better understood in the dynamic approach of cultural values as proposed here.
This paper focuses on entrepreneurship and private sector development in Ghana with regard to the government’s initiative towards supporting private sector development through the Microfinance & Small Loans Centre (MASLOC) and the National Board for Small Scale Industries (NBSSI) initiatives to support new and existing small and medium-scale enterprises (SMEs) in diverse industries. The study addresses some of the main problems facing the two government-sponsored initiatives and issues with accessing venture capital for business start-ups in Ghana. The objective of the study is to identify possible strategies through which the MASLOC and NBSSI could be improved to serve the needs of their customers more effectively and efficiently. Enhancing the performance of these public organizations could offer many SMEs in Ghana take advantage of the new opportunities in the domestic and global business environments. The questions to be addressed are; to what extent do the activities of the NBSSI and MASLOC meet the needs of SMEs in Ghana? What challenges are associated with their services and how can management of the two organizations address the challenges they face more appropriately? The methodology is based on the qualitative and quantitative approaches, involving interviews and the administration of questionnaires and surveys to achieve the study’s objectives and goals. Based on the identified challenges, the study concludes with findings and recommendations for the management of NBSSI and MASLOC as well as entrepreneurs engaged in different SMEs in diverse industries and policy makers.
Experiential Learning through the Transformational Incubation Programme: a Ghanaian case study
(2017)
This paper explores experiential learning theory (ELT) from a case study describing the Transformational Incubation Programme for Coventry University Alumni in Ghana. The incubator represents a collaboration between Coventry University and British Council Ghana. The aim of the programme is to embed a blended, experiential learning approach to practice-based entrepreneurship education via an incubator designed to support scalable business start-up and growth. world venture creation, business development and acceleration. The paper offers a generic framework for Transformational entrepreneurship experiential learning in this context. The incubator offers an opportunity to engage with practice-oriented and experience based learning applied to real.