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3D Printers as Sociable Technologies: Taking Appropriation Infrastructures to the Internet of Things
(2017)
From video games to mobile augmented reality, 3D interaction is everywhere. But simply choosing to use 3D input or 3D displays isn't enough: 3D user interfaces (3D UIs) must be carefully designed for optimal user experience. 3D User Interfaces: Theory and Practice, Second Edition is today's most comprehensive primary reference to building outstanding 3D UIs. Four pioneers in 3D user interface research and practice have extensively expanded and updated this book, making it today's definitive source for all things related to state-of-the-art 3D interaction.
A trace of the execution of a concurrent object-oriented program can be displayed in two-dimensions as a diagram of a non-metric finite geometry. The actions of a programs are represented by points, its objects and threads by vertical lines, its transactions by horizontal lines, its communications and resource sharing by sloping arrows, and its partial traces by rectangular figures.
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.
This work presents the analysis of data recorded by an eye tracking device in the course of evaluating a foveated rendering approach for head-mounted displays (HMDs). Foveated rendering methods adapt the image synthesis process to the user’s gaze and exploiting the human visual system’s limitations to increase rendering performance. Especially, foveated rendering has great potential when certain requirements have to be fulfilled, like low-latency rendering to cope with high display refresh rates. This is crucial for virtual reality (VR), as a high level of immersion, which can only be achieved with high rendering performance and also helps to reduce nausea, is an important factor in this field. We put things in context by first providing basic information about our rendering system, followed by a description of the user study and the collected data. This data stems from fixation tasks that subjects had to perform while being shown fly-through sequences of virtual scenes on an HMD. These fixation tasks consisted of a combination of various scenes and fixation modes. Besides static fixation targets, moving tar- gets on randomized paths as well as a free focus mode were tested. Using this data, we estimate the precision of the utilized eye tracker and analyze the participants’ accuracy in focusing the displayed fixation targets. Here, we also take a look at eccentricity-dependent quality ratings. Comparing this information with the users’ quality ratings given for the displayed sequences then reveals an interesting connection between fixation modes, fixation accuracy and quality ratings.
The detection of human skin in images is a very desirable feature for applications such as biometric face recognition, which is becoming more frequently used for, e.g., automated border or access control. However, distinguishing real skin from other materials based on imagery captured in the visual spectrum alone and in spite of varying skin types and lighting conditions can be dicult and unreliable. Therefore, spoofing attacks with facial disguises or masks are still a serious problem for state of the art face recognition algorithms. This dissertation presents a novel approach for reliable skin detection based on spectral remission properties in the short-wave infrared (SWIR) spectrum and proposes a cross-modal method that enhances existing solutions for face verification to ensure the authenticity of a face even in the presence of partial disguises or masks. Furthermore, it presents a reference design and the necessary building blocks for an active multispectral camera system that implements this approach, as well as an in-depth evaluation. The system acquires four-band multispectral images within T = 50ms. Using a machine-learning-based classifier, it achieves unprecedented skin detection accuracy, even in the presence of skin-like materials used for spoofing attacks. Paired with a commercial face recognition software, the system successfully rejected all evaluated attempts to counterfeit a foreign face.
A new method for design space exploration and optimization, Surrogate-Assisted Illumination (SAIL), is presented. Inspired by robotics techniques designed to produce diverse repertoires of behaviors for use in damage recovery, SAIL produces diverse designs that vary according to features specified by the designer. By producing high-performing designs with varied combinations of user-defined features a map of the design space is created. This map illuminates the relationship between the chosen features and performance, and can aid designers in identifying promising design concepts. SAIL is designed for use with compu-tationally expensive design problems, such as fluid or structural dynamics, and integrates approximative models and intelligent sampling of the objective function to minimize the number of function evaluations required. On a 2D airfoil optimization problem SAIL is shown to produce hundreds of diverse designs which perform competitively with those found by state-of-the-art black box optimization. Its capabilities are further illustrated in a more expensive 3D aerodynamic optimization task.
Current global challenges such as climate change, lack of resources, desertification, land degradation as well as loss of biodiversity can ultimately be due to human actions. Reasons are excessive production and consumption of goods and services, along with using and consuming natural resources, causing emissions and waste products. Demand in the form of consumption and supply in the form of production are closely intertwined.
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.
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.
Populating virtual worlds with intelligent agents can drastically improve a user's sense of presence. Applying these worlds to virtual training, simulations, or (serious) games, often requires multiple agents to be simulated in real time. The process of generating believable agent behavior starts with providing a plausible perception and attention process that is both efficient and controllable. We describe a conceptual framework for synthetic perception that specifically considers the mentioned requirements: plausibility, real-time performance, and controllability. A sample implementation will focus on sensing, attention, and memory to demonstrate the framework's capabilities in a real-time game engine scenario. A combination of dynamic geometric sensing and false coloring with static saliency information is provided to exemplify the collection of environmental stimuli. The subsequent attention process handles both bottom-up processing and task-oriented, top-down factors. Behavioral results can be influenced by controlling memory and attention The example case is demonstrated and discussed alongside future extensions.
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.
Enterprises demand universities not to limit education to theoretical knowledge, but instead, to prepare students for future challenges in the job. While demanding a focus on current technologies and practices appears reasonable, it contradicts academia’s general focus on sustainable knowledge. This “conflict-ofinterest” can be bridged through extra-curricular professional training. MOOCs are hyped as solution because they allow to simultaneously addressing masses of students. However, with the increasing number of learners, anonymity in education increases and first-level support decreases. Within the extracurricular online program erp4students we found that individual support is considered most relevant to successfully complete professional training.
Blended Learning Set up of the Master Programme "Analysis and Design of Social Protection Systems"
(2017)
The master's programme "Analysis and Design of Social Protection Systems" is a newly designed programme. The international Master’s programme is aimed at students who wish to deal with social security systems and who are also interested in intercultural exchange. The on-campus and online phases provide students with the opportunity to develop an international network, while facilitating the combination of studies and professional engagement.
This book presents theory and latest application work in Bond Graph methodology with a focus on:
Hybrid dynamical system models, Model-based fault diagnosis, model-based fault tolerant control, fault prognosis and also addresses Open thermodynamic systems with compressible fluid flow, and Distributed parameter models of mechanical subsystems.
In addition, the book covers various applications of current interest ranging from motorised wheelchairs, in-vivo surgery robots, walking machines to wind-turbines.The up-to-date presentation has been made possible by experts who are active members of the worldwide bond graph modelling community.
This book is the completely revised 2nd edition of the 2011 Springer compilation text titled Bond Graph Modelling of Engineering Systems – Theory, Applications and Software Support. It extends the presentation of theory and applications of graph methodology by new developments and latest research results.
Like the first edition, this book addresses readers in academia as well as practitioners in industry and invites experts in related fields to consider the potential and the state-of-the-art of bond graph modelling.
Recently, we discovered a cholinergic mechanism that inhibits the adenosine triphosphate (ATP)-dependent release of interleukin-1 beta (IL-1 beta) by human monocytes via nicotinic acetylcholine receptors (nAChRs) composed of alpha 7, alpha 9 and/or alpha 10 subunits. Furthermore, we identified phosphocholine (PC) and dipalmitoylphosphatidylcholine (DPPC) as novel nicotinic agonists that elicit metabotropic activity at monocytic nAChR. Interestingly, PC does not provoke ion channel responses at conventional nAChRs composed of subunits alpha 9 and alpha 10. The purpose of this study is to determine the composition of nAChRs necessary for nicotinic signaling in monocytic cells and to test the hypothesis that common metabolites of phosphatidylcholines, lysophosphatidylcholine (LPC) and glycerophosphocholine (G-PC), function as nAChR agonists. In peripheral blood mononuclear cells from nAChR gene-deficient mice, we demonstrated that inhibition of ATP-dependent release of IL-1 beta by acetylcholine (ACh), nicotine and PC depends on subunits alpha 7, alpha 9 and alpha 10. Using a panel of nAChR antagonists and siRNA technology, we confirmed the involvement of these subunits in the control of IL-1 beta release in the human monocytic cell line U937. Furthermore, we showed that LPC (C16:0) and G-PC efficiently inhibit ATP-dependent release of IL-1 beta. Of note, the inhibitory effects mediated by LPC and G-PC depend on nAChR subunits alpha 9 and alpha 10, but only to a small degree on alpha 7. In Xenopus laevis oocytes heterologously expressing different combinations of human alpha 7, alpha 9 or alpha 10 subunits, ACh induced canonical ion channel activity, whereas LPC, G-PC and PC did not. In conclusion, we demonstrate that canonical nicotinic agonists and PC elicit metabotropic nAChR activity in monocytes via interaction of nAChR subunits alpha 7, alpha 9 and alpha 10. For the metabotropic signaling of LPC and G-PC, nAChR subunits alpha 9 and alpha 10 are needed, whereas alpha 7 is virtually dispensable. Furthermore, molecules bearing a PC group in general seem to regulate immune functions without perturbing canonical ion channel functions of nAChR.
An increased bronchoconstrictor response is a hallmark in the progression of obstructive airway diseases. Acetylcholine and 5-hydroxytryptamine (5-HT, serotonin) are the major bronchoconstrictors. There is evidence that both cholinergic and serotonergic signaling in airway smooth muscle (ASM) involve caveolae. We hypothesized that caveolin-1 (cav-1), a structural protein of caveolae, plays an important regulatory role in ASM contraction. We analyzed airway contraction in different tracheal segments and extra-and intrapulmonary bronchi in cav-1 deficient (cav-1-/-) and wild-type mice using organ bath recordings and videomorphometry of methyl-beta-cyclodextrin (MCD) treated and non-treated precision-cut lung slices (PCLS). The presence of caveolae was investigated by electron microscopy. Receptor subtypes driving 5-HT-responses were studied by RT-PCR and videomorphometry after pharmacological inhibition with ketanserin. Cav-1 was present in tracheal epithelium and ASM. Muscarine induced a dose dependent contraction in all airway segments. A significantly higher Emax was observed in the caudal trachea. Although, caveolae abundancy was largely reduced in cav-1-/- mice, muscarine-induced airway contraction was maintained, albeit at diminished potency in the middle trachea, in the caudal trachea and in the bronchus without changes in the maximum efficacy. MCD-treatment of PLCS from cav-1-/- mice reduced cholinergic constriction by about 50%, indicating that cholesterol-rich plasma domains account for a substantial portion of the muscarine-induced bronchoconstriction. Notably, cav-1-deficiency fully abrogated 5-HT-induced contraction of extrapulmonary airways. In contrast, 5-HT-induced bronchoconstriction was fully maintained in cav-1-deficient intrapulmonary bronchi, but desensitization upon repetitive stimulation was enhanced. RT-PCR analysis revealed 5-HT1B, 5-HT2A, 5-HT6, and 5-HT7 receptors as the most prevalent subtypes in the airways. The 5-HT-induced-constriction in PCLS could be antagonized by ketanserin, a 5-HT2A receptor inhibitor. In conclusion, the role of cav-1, caveolae, and cholesterol-rich plasma domains in regulation of airway tone are highly agonist-specific and dependent on airway level. Cav-1 is indispensable for serotonergic contraction of extrapulmonary airways and modulates cholinergic constriction of the trachea and main bronchus. Thus, cav-1/caveolae shall be considered in settings such as bronchial hyperreactivity in common airway diseases and might provide an opportunity for modulation of the constrictor response.
Multiple myeloma is the second most common hematological malignancy. Despite all the progress made in treating multiple myeloma, it still remains an incurable disease. Patients are left with a median survival of 4-5 years. The combined treatment of multiple myeloma with histone deacetylase inhibitors and cytokine-induced killer cells provides a promising targeted treatment option for patients. This study investigated the impact of a combined treatment compared to treatment with histone deacetylase inhibitors. The experiments revealed that a treatment with histone deacetylase (HDAC) inhibitors could reduce cell viability to 59% for KMS 18 cell line and 46% for the U-266 cell line. The combined treatment led to a decrease of cell viability to 33% for KMS 18 and 27% for the U-266 cell line, thus showing a significantly better efficacy than the single treatment.
Small and Medium Enterprises (SMEs) are engine of economy both for developed and developing countries. They play a significant role in income generation, job creation, poverty reduction and reducing income inequality. In Burundi, key stakeholders such as policy-makers as well as other international and national actors have made more effort to develop the segment of SMEs. Indeed, many start-ups have been created but are however, exposed to several challenges in their business operations. This paper aimed at investigating main critical barriers to SMEs growth and development in Burundi. The research was based upon a sample survey of small firms in Burundi and 314 small enterprises were surveyed. Rural start-ups’ critical barriers identified are mainly poor management, lack of access to market flow, lack of working capital, inadequate qualified workforce and low selling prices. On the other hand, five severe obstacles for urban SMEs identified are insecurity, access to financing, macroeconomic situation, lack of customers and unfair competition. A better understanding of all these barriers that SMEs are facing is useful to set up best strategies susceptible to increase their growth.
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.
Dare – Democracy and Science
(2017)
The MAP-Elites algorithm produces a set of high-performing solutions that vary according to features defined by the user. This technique to 'illuminate' the problem space through the lens of chosen features has the potential to be a powerful tool for exploring design spaces, but is limited by the need for numerous evaluations. The Surrogate-Assisted Illumination (SAIL) algorithm, introduced here, integrates approximative models and intelligent sampling of the objective function to minimize the number of evaluations required by MAP-Elites.
The ability of SAIL to efficiently produce both accurate models and diverse high-performing solutions is illustrated on a 2D airfoil design problem. The search space is divided into bins, each holding a design with a different combination of features. In each bin SAIL produces a better performing solution than MAP-Elites, and requires several orders of magnitude fewer evaluations. The CMA-ES algorithm was used to produce an optimal design in each bin: with the same number of evaluations required by CMA-ES to find a near-optimal solution in a single bin, SAIL finds solutions of similar quality in every bin.
The technological development of the digital computer and new options to collect, store and transfer mass data have changed the world in the last 40 years. Moreover, due to the ongoing progress of computer power, the establishment of the Internet as critical infrastructure and the options of ubiquitous sensor systems will have a dramatic impact on economies and societies in the future. We give a brief overview about the technological basics especially with regard to the exponential growth of big data and current turn towards sensor-based data collection. From this stance, we reconsider the various dimensions of personal data and and market mechanisms that have an impact of data usage and protection.
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.
The non-farm sector is critical for the socio-economic development of Ghana especially the rural poor. Literature suggest that people engage in non-farm enterprises as a way out of poverty or a survival strategy, perhaps as a substitute for the landless. This paper analyses the determinants of individual participation in non-farm enterprises and the intensity of participation. The paper uses EGC/ISSER Socio-Economic Panel Survey data collected in 2009. The paper estimated the determinants of participation using a probit model and then estimated the intensity of participation using a truncated regression model. The results indicate that majority of women (about 73%) are engaged in non-farm enterprises in rural Ghana. The study found that females tended to participate more in non-farm self-employment and are less likely to participate in non-farm wage employment. The results further showed that individual characteristics such as the gender of the individual, being head of a household, being the spouse of a household head, having formal education, age of the individual, having access to credit, possessing a mobile phone, per capita landing holding and ownership of livestock influenced the participation of individuals in self-and wage employment. Results from truncated regression model for self-employed enterprises showed that having access to mobile phones, owning more livestock and electricity are important in determining the intensity of participation in self-employed enterprises. For wage-employment, being a household head, spouse of household head, having access to mobile phone and owning more livestock increased the number of days working on wage employment. Education is relevant for employment in the non-farm sector especially wage-employment. Government should play a lead role in making formal education accessible to the rural people. Deliberate policies should focus on addressing critical factors such as access to credit, mobile phone, electricity and education which are relevant for increasing participation intensity in rural enterprises.
A device includes an input to sequential data associated to a face; a predictor configured to predict facial parameters; and a corrector configured to correct the predicted facial parameters on the basis of input data, the input data containing geometric measurements and other information. A related method and a related computer program are also disclosed.
Do remittances and social assistance transfers have different impacts on household’s expenditure patterns? While two separate strands of literature have looked at how social assistance or remittances have been spent, few studies have compared them directly. Using data from a household survey conducted in Moldova in 2011, this paper assesses the impact both types of transfers have on household expenditure patterns. Contrary to the common assumption that money is fungible, we find that social assistance and remittances have different impacts on expenditure patterns (having controlled for potential endogeneity). In other words, where the income comes from can determine how it is spent. As such, different sources of income may have different poverty impacts. In our sample, the two types of transfers are received by different, but slightly overlapping population groups. The fact that the two transfers are spent in different ways means that, to some extent, social assistance and remittances are complements rather than substitutes.
Entrepreneurship education serves a conduit for new venture creation as it provides the knowledge and skills needed to increase the self-efficacy of individuals to start and run new businesses and to grow existing ones. This study, therefore, sought to assess the relationship between the approaches to the teaching of entrepreneur-ship and entrepreneurial intention on a cohort of 292 respondents consisting of students who have studied entrepreneurship in three selected Universities. A structured questionnaire was used to obtain data randomly from students. The canonical correlation results indicate that education for and through entrepreneurship is the best approach to promoting entrepreneurial intensity among University students, if the aim of teaching entrepreneur-ship is to promote start-up activities. The findings provide valuable insights for institutions of higher learning and policy makers in Ghana with respect to the appropriate methodologies to be adopted in the teaching of entrepreneurship in our universities.
This study sought to determine the relationship between entrepreneurial education and youth employability and economic development in Kenya. A descriptive cross sectional design was used to collect data, with the main data collection instrument being a semi structured questionnaire. The population of the study comprised the micro, small and medium scale enterprises in Nairobi, Kenya. Out of the 100 questionnaires issued, 93 were completed and returned giving a response rate of 93%. Descriptive analysis (means and standard deviations ) and inferential analysis was used to analyze the data. Regression and correlation analysis was done to test the hypotheses. It was found that several indicators of entrepreneurial education had a significantly positive influence on youth employability. For example, entrepreneurial education enhances opportunity recognition as an indicator of entrepreneurial education was statistically significantly correlated with the statement that entrepreneurship endeavor is an employment alternative as an indicator of youth employability (r = 331**, P = 0.01). Similarly, the statement that entrepreneurial education sharpens competitiveness had a significantly positive influence on the statement that entrepreneurship endevour is an employment alternative (r =.313** P = 0.01). The overall model for entrepreneurial education and youth employability had an R Square value of 0.151, and an F value of 3.086, (p = 0.013 < 0.05), indicating that the influence is significant at the 0.05 level. The study found that most indicators of youth employability had a significantly positive correlation with indicators of economic development. It was found that there was a significant positive correlation between entrepreneurial education enhances new product and service development and entrepreneurial education reduces youth unemployment (r =0.304**, P = 0.01), while entrepreneurial education enhances new product and service development also has a positive correlation with entrepreneurial education reduces youth unemployment (.304** , P = 0.01). The overall model for youth employability and economic development had an R square value of .087 and F value of 2.103, p =0.87 > 0.05, indication that although youth employability is responsible for 8.7% of economic development, the effect is not statistically significant. The implication for this is that entrepreneurial education should be encouraged as a way of enhancing entrepreneurial thinking among the youth, so that they can use this to venture into self employment. However, this study did not find a significant direct link between youth employability and economic development, and this can only be implied. We suggest increased government support for entrepreneurship training and for closer industry university collaboration and partnerships in order to accelerate economic development.
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.
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.
Telecollaborating and communicating in online contexts using English as a Lingua Franca (ELF) requires students to develop multiple literacies in addition to foreign language skills and intercultural communicative competence. This chapter looks at the intersection of technology and teaching ELF, examining mutual contributions of technologies, more specifically Web 2.0, and ELF to each other, and the challenges in designing and implementing collaboration projects across cultures. Moreover, it looks at how the development of digital competencies in ELF (DELF) can be enhanced through the implementation of Web 2.0 mediated intercultural dialogues. The detail of the research design including internet tools used, participants and tasks are also discussed. Data analysis points to a positive attitude towards telecollaboration, also providing confirmation of some of the problems identified in theoretical framework, such as different levels of personal engagement.
Neuroevolution methods evolve the weights of a neural network, and in some cases the topology, but little work has been done to analyze the effect of evolving the activation functions of individual nodes on network size, an important factor when training networks with a small number of samples. In this work we extend the neuroevolution algorithm NEAT to evolve the activation function of neurons in addition to the topology and weights of the network. The size and performance of networks produced using NEAT with uniform activation in all nodes, or homogenous networks, is compared to networks which contain a mixture of activation functions, or heterogenous networks. For a number of regression and classification benchmarks it is shown that, (1) qualitatively different activation functions lead to different results in homogeneous networks, (2) the heterogeneous version of NEAT is able to select well performing activation functions, (3) the produced heterogeneous networks are significantly smaller than homogeneous networks.
Over the past decades, growing trends in social media, e-literacy and globalisation have led to the increased use of electrical and electronic equipment (EEE) in offices, schools, homes, hospitals and other institutions. Although, there are more efforts at introducing diversity, innovation and increased use of EEE, there had been limited effort at managing the end?of?life of these electronic devices. Evidence from previous research showed that the management of the end of life of electronic waste is highly dominated by Micro, Small and Medium Sized Enterprises (MSMEs) in the informal sector who employ more crude technology in their operations. This exploratory study therefore, sought to examine the activities of corporate bodies and MSMEs (formal and informal) in the e-waste sector in the Accra and Kumasi Metropolitan Areas in Ghana. Data was collected via questionnaires and interview from randomly selected respondents in the two metropolises. Results reveal that even though corporate institutions import a lot of electrical and electronic equipment, they do not have any policies on disposal of the e-waste generated. Thus, a high percentage of the e-waste generated is processed by the informal sector. The implications of the results are that policy makers and other stakeholders should encourage MSMEs to formalize their activities, support investment and green business development as well as funding and training for MSMEs operating in the sector.
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.
ICT integration by universities teaching professionals is emerging as a major concern, this study demonstrate the need to address the integration problem by encouraging existing metrics use in indexing ICT integration as an ICT governance strategy. Quality of integration depends on quality indexing which also depend on quality of existing metrics and their use. Considering the role that University Information Technology Teaching Professionals’ (UITTPs) continuous improvement indexing can offer, towards autonomic governance of the continuous emerging ICTs in the university teaching, this study examined extent in use of existing ICT integration metrics to index ICT integration by the UITTPs. Six metrics for ICT integration were investigated; time, workshop course content relevance, technical malfunctions, support conditions, support services, and motivation and commitment to student learning and staff professional development metrics. Descriptive survey design was used in which interviews were conducted to UITTPs in three (3) public and three (3) private purposively selected universities in Kenya. The findings were analyzed descriptively and inferentially using Kendall’s correlation of concordance and tested using Chi-square on the extent of concordance and presented with help of frequency tables, figures and percentages. The findings revealed that all the metrics are rarely used for indexing ICT integration (32.8%), and most UITTPs were in discordance on this level of all the six metrics use except for support condition. This implied that the use of metrics for indexing integration has not been formalized across the Kenyan universities. Universities need to be encouraged to identify suitable metrics, formalize them and improve their frequency in use. Secondly, socio based metrics such as content relevance are used more frequently for indexing integration as compared to Technical metrics, socio-technical metrics balance therefore need to be emphasized by the universities management when determining and using metrics for indexing ICT integration.
Exosomes derived from human autologous conditioned serum are nanocarriers for IL-6 and TNF-alfa
(2017)
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.
Exploring Gridmap-based Interfaces for the Remote Control of UAVs under Bandwidth Limitations
(2017)
OpenDaylight (ODL) is a commercial, collaborative, open-source platform to accelerate the adoption and innovation of Software Defined Networking (SDN) and Network Function Visualization. This paper describes the novel ODL architecture in a simplified way to grasp a better understanding of such architecture. ODL architecture intends to foster new innovation and accelerate adoption of programming the network. The innovation of Model-Driven Service Abstraction Layer (MD-SAL) in the architecture leads to developing models for automatic management and configuration of the networks. MD-SAL provides ODL with the ability to support any protocol talking to the network elements as well as any network application. The flexibility inherent in ODL architecture could enable ODL to shape the next generation networks.
The MAP-Elites algorithm produces a set of high-performing solutions that vary according to features defined by the user. This technique has the potential to be a powerful tool for design space exploration, but is limited by the need for numerous evaluations. The Surrogate-Assisted Illumination algorithm (SAIL), introduced here, integrates approximative models and intelligent sampling of the objective function to minimize the number of evaluations required by MAP-Elites.
The ability of SAIL to efficiently produce both accurate models and diverse high performing solutions is illustrated on a 2D airfoil design problem. The search space is divided into bins, each holding a design with a different combination of features. In each bin SAIL produces a better performing solution than MAP-Elites, and requires several orders of magnitude fewer evaluations. The CMA-ES algorithm was used to produce an optimal design in each bin: with the same number of evaluations required by CMA-ES to find a near-optimal solution in a single bin, SAIL finds solutions of similar quality in every bin.
Food losses occur for many reasons at all stages of supply chains for fruits, vegetables and potatoes. They cause immense economic, environmental and social costs – not only in developing countries but also in developed countries. According to the European Commission, about 90 million tonnes of food are wasted annually in Europe alone. However, particularly for the early stages of supply chains for fruits, vegetables and potatoes there is still a lack of reliable data. Thus, one objective of this study is to contribute to the quantification of food losses between field and retail, where the main focus is set on potatoes, apples, carrots, strawberries and asparagus. Furthermore, neither reasons why products are removed from the supply chains nor their alternative uses are fully examined yet. This is why, the study takes a look on those issues, too. Results are based on data from an online survey among producers of fruits, vegetables and potatoes in North-Rhine Westphalia, Germany and on interviews with producers and other supply chain experts. Findings suggest that the products’ size and form, their storage capabilities and food safety issues have big impacts on food losses. Despite a small sample size, these findings are in line with recent studies.
Ghanaian tertiary graduates' perception of entrepreneurship education on employment opportunities
(2017)
This study focuses on whether entrepreneurship education increases entrepreneurial interest in students to set up new businesses. Entrepreneurship is a core course taken in the third year by all students of Ho Technical University. Out of the 1329 population of level 300 students of the 2016/2017 academic year, data were collected by convenience sampling from 325 (217 males and 108 females) with mean age of 24.75 years from 14 departments of four faculties. The students responded to 43-survey items derived from reviewed literature on a 5-Point Likert-Scale. It is concluded that more than 84% of the respondents agreed that entrepreneurship education informed students about entrepreneurship through the acquisition of practical skills, knowledge about acquisition of personal orientation, knowledge about business management principles and the availability of entrepreneurial support agencies. This shows that the students are highly confident of setting up their own businesses through the knowledge acquired. The study therefore has important implications for policy makers, management of tertiary institutions, students and educational evaluators on how to ensure that tertiary graduates set up entrepreneurship ventures in order to partially solve the unemployment problem in Ghana.
Simulating eye movements for virtual humans or avatars can improve social experiences in virtual reality (VR) games, especially when wearing head mounted displays. While other researchers have already demonstrated the importance of simulating meaningful eye movements, we compare three gaze models with different levels of fidelity regarding realism: (1) a base model with static fixation and saccadic movements, (2) a proposed simulation model that extends the saccadic model with gaze shifts based on a neural network, and (3) a user's real eye movements recorded by a proprietary eye tracker. Our between-groups design study with 42 subjects evaluates impact of eye movements on social VR user experience regarding perceived quality of communication and presence. The tasks include free conversation and two guessing games in a co-located setting. Results indicate that a high quality of communication in co-located VR can be achieved without using extended gaze behavior models besides saccadic simulation. Users might have to gain more experience with VR technology before being able to notice subtle details in gaze animation. In the future, remote VR collaboration involving different tasks requires further investigation.
Evolutionary illumination is a recent technique that allows producing many diverse, optimal solutions in a map of manually defined features. To support the large amount of objective function evaluations, surrogate model assistance was recently introduced. Illumination models need to represent many more, diverse optimal regions than classical surrogate models. In this PhD thesis, we propose to decompose the sample set, decreasing model complexity, by hierarchically segmenting the training set according to their coordinates in feature space. An ensemble of diverse models can then be trained to serve as a surrogate to illumination.
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.
Hydrogen sulfide stimulates CFTR in Xenopus oocytes by activation of the cAMP/PKA signalling axis
(2017)
Hydrogen sulfide (H2S) has been recognized as a signalling molecule which affects the activity of ion channels and transporters in epithelial cells. The cystic fibrosis transmembrane conductance regulator (CFTR) is an epithelial anion channel and a key regulator of electrolyte and fluid homeostasis. In this study, we investigated the regulation of CFTR by H2S. Human CFTR was heterologously expressed in Xenopus oocytes and its activity was electrophysiologically measured by microelectrode recordings. The H2S-forming sulphur salt Na2S as well as the slow-releasing H2S-liberating compound GYY4137 increased transmembrane currents of CFTR-expressing oocytes. Na2S had no effect on native, noninjected oocytes. The effect of Na2S was blocked by the CFTR inhibitor CFTR_inh172, the adenylyl cyclase inhibitor MDL 12330A, and the protein kinase A antagonist cAMPS-Rp. Na2S potentiated CFTR stimulation by forskolin, but not that by IBMX. Na2S enhanced CFTR stimulation by membranepermeable 8Br-cAMP under inhibition of adenylyl cyclase-mediated cAMP production by MDL 12330A. These data indicate that H2S activates CFTR in Xenopus oocytes by inhibiting phosphodiesterase activity and subsequent stimulation of CFTR by cAMP-dependent protein kinase A. In epithelia, an increased CFTR activity may correspond to a pro-secretory response to H2S which may be endogenously produced by the epithelium or H2S-generating microflora.
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.
The knowledge of Software Features (SFs) is vital for software developers and requirements specialists during all software engineering phases: to understand and derive software requirements, to plan and prioritize implementation tasks, to update documentation, or to test whether the final product correctly implements the requested SF. In most software projects, SFs are managed in conjunction with other information such as bug reports, programming tasks, or refactoring tasks with the aid of Issue Tracking Systems (ITSs). Hence ITSs contains a variety of information that is only partly related to SFs. In practice, however, the usage of ITSs to store SFs comes with two major problems: (1) ITSs are neither designed nor used as documentation systems. Therefore, the data inside an ITS is often uncategorized and SF descriptions are concealed in rather lengthy. (2) Although an SF is often requested in a single sentence, related information can be scattered among many issues. E.g. implementation tasks related to an SF are often reported in additional issues. Hence, the detection of SFs in ITSs is complicated: a manual search for the SFs implies reading, understanding and exploiting the Natural Language (NL) in many issues in detail. This is cumbersome and labor intensive, especially if related information is spread over more than one issue. This thesis investigates whether SF detection can be supported automatically. First the problem is analyzed: (i) An empirical study shows that requests for important SFs reside in ITSs, making ITSs a good tar- get for SF detection. (ii) A second study identifies characteristics of the information and related NL in issues. These characteristics repre- sent opportunities as well as challenges for the automatic detection of SFs. Based on these problem studies, the Issue Tracking Software Feature Detection Method (ITSoFD), is proposed. The method has two main components and includes an approach to preprocess issues. Both components address one of the problems associated with storing SFs in ITSs. ITSoFD is validated in three solution studies: (I) An empirical study researches how NL that describes SFs can be detected with techniques from Natural Language Processing (NLP) and Machine Learning. Issues are parsed and different characteristics of the issue and its NL are extracted. These characteristics are used to clas- sify the issue’s content and identify SF description candidates, thereby approaching problem (1). (II) An empirical study researches how issues that carry information potentially related to an SF can be detected with techniques from NLP and Information Retrieval. Characteristics of the issue’s NL are utilized to create a traceability network vii of related issues, thereby approaching problem (2). (III) An empirical study researches how NL data in issues can be preprocessed using heuristics and hierarchical clustering. Code, stack traces, and other technical information is separated from NL. Heuristics are used to identify candidates for technical information and clustering improves the heuristic’s results. The technique can be applied to support components, I. and II.
Current robot platforms are being employed to collaborate with humans in a wide range of domestic and industrial tasks. These environments require autonomous systems that are able to classify and communicate anomalous situations such as fires, injured persons, car accidents; or generally, any potentially dangerous situation for humans. In this paper we introduce an anomaly detection dataset for the purpose of robot applications as well as the design and implementation of a deep learning architecture that classifies and describes dangerous situations using only a single image as input. We report a classification accuracy of 97 % and METEOR score of 16.2. We will make the dataset publicly available after this paper is accepted.
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.
Impact of atmospheric aerosols on photovoltaic energy production - Scenario for the Sahel zone
(2017)
Photovoltaic (PV) energy is one option to serve the rising global energy need with low environmental impact. PV is of particular interest for local energy solutions in developing countries prone to high solar insolation. In order to assess the PV potential of prospective sites, combining knowledge of the atmospheric state modulating solar radiation and the PV performance is necessary. The present study discusses the PV power as function of atmospheric aerosols in the Sahel zone for clear-sky-days. Daily yields for a polycrystalline silicon PV module are reduced by up to 48 % depending on the climatologically-relevant aerosol abundances.
What are the processes behind efforts for more sustainable mountain destinations in the German Alps and what are the views of different tourism stakeholders on these processes? The research deals both with threats pushing the agenda of sustainable development (such as climate change and depletion of resources), indicators of sustainable tourism (to measure the scope of change), as well as cross-border cooperation and stakeholder engagement in the German Alps. The data was collected through 30 interviews with individuals dealing with tourism development and sustainable tourism development in the German Alps. The findings suggest that a holistic approach and collection and dissemination of data and knowledge on sustainability are the basis for developing sustainable mountain tourism. Implementation and monitoring should focus on specific flagship sustainable tourism products, as well as on a destination in a broader sense and the sustainable tourism market. Three themes emerged as important for implementation of sustainable tourism in the German Alps: indicators of sustainable tourism, cross-border cooperation and stakeholder engagement.
Argentina substantially contributes to the global organic agriculture and food sector due to its large areas of organically managed agricultural land. However, most of the organic production is foreseen for export. Overall, food supply for the domestic organic market is hardly tapped. This study investigates the current importance of organic agriculture and food production as well as its consumption within the country. The novelty of the study also lies in the observation, documentation and analysis of latest stakeholder-driven developments towards organic agriculture and food. The publication allows to make the Argentinian organic market significantly more visible for the international audience.