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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.
BACKGROUND
Given the unreliable self-report in patients with dementia, pain assessment should also rely on the observation of pain behaviors, such as facial expressions. Ideal observers should be well trained and should observe the patient continuously in order to pick up any pain-indicative behavior; which are requisitions beyond realistic possibilities of pain care. Therefore, the need for video-based pain detection systems has been repeatedly voiced. Such systems would allow for constant monitoring of pain behaviors and thereby allow for a timely adjustment of pain management in these fragile patients, who are often undertreated for pain.
METHODS
In this road map paper we describe an interdisciplinary approach to develop such a video-based pain detection system. The development starts with the selection of appropriate video material of people in pain as well as the development of technical methods to capture their faces. Furthermore, single facial motions are automatically extracted according to an international coding system. Computer algorithms are trained to detect the combination and timing of those motions, which are pain-indicative.
RESULTS/CONCLUSION
We hope to encourage colleagues to join forces and to inform end-users about an imminent solution of a pressing pain-care problem. For the near future, implementation of such systems can be foreseen to monitor immobile patients in intensive and postoperative care situations.
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.
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.
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.
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.
In order to achieve the highest possible performance, the ray traversal and intersection routines at the core of every high-performance ray tracer are usually hand-coded, heavily optimized, and implemented separately for each hardware platform—even though they share most of their algorithmic core. The results are implementations that heavily mix algorithmic aspects with hardware and implementation details, making the code non-portable and difficult to change and maintain.
In this paper, we present a new approach that offers the ability to define in a functional language a set of conceptual, high-level language abstractions that are optimized away by a special compiler in order to maximize performance. Using this abstraction mechanism we separate a generic ray traversal and intersection algorithm from its low-level aspects that are specific to the target hardware. We demonstrate that our code is not only significantly more flexible, simpler to write, and more concise but also that the compiled results perform as well as state-of-the-art implementations on any of the tested CPU and GPU platforms.
This article analyzes how humanitarian and/or development organizations acting as intermediaries between scientists and vulnerable populations aim to make environmental changes visible while trying to meet local needs and demands for sustainable livelihoods. Based on an in-depth organizational case study in Southern Thailand, the research analyses the use of visualization tools to foster environmental knowledge and literacy while supporting both policymaking as well as citizen engagement. Drawing on insights from sociology of organizations, the study discusses the organizational reasons for the use of visualization tools, outlining the underlying coercive, mimetic and normative pressures that facilitate their proliferation in the context of environmental communication. The results show that both the participatory approach as well as the use of audiovisual and digital tools to communicate project goals and results have become indispensable and institutionalized tools in the organizational field of humanitarian and development aid. In this context, organizations have become intermediaries and translators between ‘climate risk’ scientists and ‘at risk’ people, thus, facilitating environmental communication. The results show that questions of trust and ownership of ideas play an important role in the context of livelihood related projects linked to climate change adaptation. In this context, not only does the style and content of communication, but also the relationship between the parties who communicate, have an impact upon the success or failure of managing options in climate change adaptation.
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.
3D Printers as Sociable Technologies: Taking Appropriation Infrastructures to the Internet of Things
(2017)
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.
This study aims to highlight the significance of social protection as an autonomous strategy for migration policies and research. It focuses particularly on the German strategies for combating the causes of flight and migration. By managing migration flows, stabilizing societies and encouraging economic development, social protection can play an important role in reducing migration flows. At the same time, social protection can act as a stabilizer in the countries of origin and accelerate economic growth as well as supporting individual decisions to return to the countries of origin.
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.
Continued growth in international experiences for U.S. co++6llege students is a favorable trend. However, the most substantial increase has occurred with of short-term study abroad programs. Many of these programs include extensive travel instead of involving a single site. There is great danger that if not properly managed, these types of international educational experience will default into little more than an organized group tour.
In these types of programs it is challenging to induce student participants to engage meaningfully with local residents as the traveling group tends to form into its own portable society. In addition, the current state of wireless communications means that students participating in these types of programs can easily stay plugged into their home social networks which further reduces meaningful interactions in the cultures being visited.
Incorporating well designed research projects into short-term study abroad programs holds the potential to offset some of the inherent limitations of such programs. Research projects can serve both to prepare the students for the trip and promote meaningful cross-cultural interaction while the program is underway.
In this paper, the authors provide suggestions based on their experiences with short-term travel abroad programs which incorporated student research. Several potential problems are identified and suggestions are given for project design.
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.
Diese Arbeit beschäftigt sich mit der Effizienz der Seitenkanal-Kryptanalyse. In Teil II dieser Arbeit demonstrieren wir, wie die Laufzeit der wichtigsten Analysewerkzeuge mit Hilfe der CUDA Plattform erheblich gesteigert werden kann. Zweitens untersuchen wir neue Ansätze der profilierenden Seitenkanal-Kryptanalyse. Der Forschungszweig des maschinellen Lernens kann für deutliche Verbesserungen adaptiert werden, wurde jedoch wenig dahingehend untersucht. In Teil III dieser Arbeit präsentieren wir zwei neue Methoden, die einige Gemeinsamkeiten jedoch auch einige Unterschiede aufbieten, sodass sich Prüfergebnisse in einem vollständigeren Bild zeigen lassen. Darüber hinaus schlagen wir in Teil IV eine Seitenkanalanwendung zum Schutz geistigen Eigentums (IP) vor. In Teil V beschäftigen wir uns tiefergehend mit praktischer Seitenkanal-Kryptanalyse, indem wir Attacken auf einen Sicherheitsmikrokontroller durchführen, der Anwendung in einer, in Deutschland weit verbreiteten, EC Karte findet.
Mutations in SELENBP1, encoding a novel human methanethiol oxidase, cause extraoral halitosis
(2017)
This study deals with the in-situ detection of volume fractions of melt in labradorite and basalt at 0.3 GPa pressure and temperatures ranging from 400–1500 °C. Methods used were frequency dependent electrical conductivity (EC) and energy dispersive X-ray diffraction (EDX). These techniques allowed melt fraction determination under in-situ pressure and temperature conditions, while optical analysis (SEM) was performed on quenched samples. EC allowed detecting melt frac- tions as low as 0.03 due to changes in dielectric properties. Increasing melt fractions caused the formerly isolated melt bubbles to interconnect along grain boundaries, thus increasing the bulk conductivity. Electrical conductivity thus provides a measure for both, the formation of melt (dielectric property) and the degree of interconnection of melt (bulk conductivity). Energy dispersive X-ray diffraction experiments (EDX) provided an additional measure for the volume fraction of melt. EDX diffraction data were used to calculate the volume fraction of melt on the basis of the peak to background ratio. In a final step the experimental data (SEM, EC, EDX) were compared with geometric models of melt distribution, namely the Archie-, cube-, tube-, Hashin-Shtrikman HS + and HS - model. The electrical "polarisability" data closely fit the HS + model, while bulk conductivity data were found to be less sensitive for melt fraction detection.
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.
As robots are becoming ubiquitous and more capable, the need for introducing solid robot software development methods is pressing to increase robots' task spectrum. This thesis is concerned with improving software engineering of robot perception systems. The presented research employs a model-based approach to provide the means to represent knowledge about robotics software. The thesis is divided into three parts, namely research on the specification, deployment and adaptation of robot perception systems.
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.
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.
Synthesis of serving policies for objects flow in the system with refillable storage component
(2017)
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.
The Sparse Matrix Vector Multiplication is an important operation on sparse matrices. This operation is the most time consuming operation in iterative solvers and therefore an efficient execution of that operation is of great importance for many applications. Numerous different storage formats that store sparse matrices efficiently have already been established. Often, these storage formats utilize the sparsity pattern of a matrix in an appropiate manner. For one class of sparse matrices the nonzero values occur in small dense blocks and appropriate block storage formats are well suited for such patterns. But on the other side, these formats perform often poor on general matrices without an explicit / regular block structure. In this paper, the newly developed sparse matrix format DynB is introduced. The aim is to efficiently use several optimization approaches and vectorization with current processors, even for matrices without an explicit block structure of nonzero elements. The DynB matrix format uses 2D rectangular blocks of variable size, allowing fill-ins per block of explicit zero values up to a user controllable threshold. We give a simple and fast heuristic to detect such 2D blocks in a sparse matrix. The performance of the Sparse Matrix Vector Multiplication for a selection of different block formats and matrices with different sparsity structures is compared. Results show that the benefit of blocking formats depend – as to be expected – on the structure of the matrix and that variable sized block formats like DynB can have advantages over fixed size formats and deliver good performance results even for general sparse matrices.
In this paper we propose an implement a general convolutional neural network (CNN) building framework for designing real-time CNNs. We validate our models by creating a real-time vision system which accomplishes the tasks of face detection, gender classification and emotion classification simultaneously in one blended step using our proposed CNN architecture. After presenting the details of the training procedure setup we proceed to evaluate on standard benchmark sets. We report accuracies of 96% in the IMDB gender dataset and 66% in the FER-2013 emotion dataset. Along with this we also introduced the very recent real-time enabled guided back-propagation visualization technique. Guided back-propagation uncovers the dynamics of the weight changes and evaluates the learned features. We argue that the careful implementation of modern CNN architectures, the use of the current regularization methods and the visualization of previously hidden features are necessary in order to reduce the gap between slow performances and real-time architectures. Our system has been validated by its deployment on a Care-O-bot 3 robot used during RoboCup@Home competitions. All our code, demos and pre-trained architectures have been released under an open-source license in our public repository.
In order to achieve the highest possible performance, the ray traversal and intersection routines at the core of every high-performance ray tracer are usually hand-coded, heavily optimized, and implemented separately for each hardware platform—even though they share most of their algorithmic core. The results are implementations that heavily mix algorithmic aspects with hardware and implementation details, making the code non-portable and difficult to change and maintain.
In this paper, we present a new approach that offers the ability to define in a functional language a set of conceptual, high-level language abstractions that are optimized away by a special compiler in order to maximize performance. Using this abstraction mechanism we separate a generic ray traversal and intersection algorithm from its low-level aspects that are specific to the target hardware. We demonstrate that our code is not only significantly more flexible, simpler to write, and more concise but also that the compiled results perform as well as state-of-the-art implementations on any of the tested CPU and GPU platforms.
Biomass in general, wood and grasses in particular represent attractive renewable sources for the fabrication of so-called building block chemicals (1). Thus, environmentally benign antimicrobial nanoparticles based on a silver-infused lignin core were recently reported underlying the high potential for valorization of lignin (2). The contribution presents specific correlations regarding the structural differences of lignins depending on both: source (wood vs. grass) and isolation procedure (Kraft vs. Organosolv). Special focus will be drawn on detailed structure deviations caused by Miscanthus genotypes (M. gigantheus, M. robustus, M. sisnensis).
Recent approaches in scaffold engineering for bone defects feature hybrid hydrogels made of a polymeric network (retains water and provides light and porous structures) and inorganic ceramics (add mechanical strength and improve cell-adhesion). Innovative scaffold materials should also induce bone tissue formation and incorporation of stem cells (osteogenic differentiation) and/or growth factors (inducing/supporting differentiation). Recently, purinergic P2X and P2Y receptors have been found to significantly influence the osteogenic differentiation process of human mesenchymal stem cells (hMSC). (1) Aim of this work is to develop polysaccharide (PS) composites to be used as scaffolds containing complementary receptor ligands to enable guided stem cell differentiation towards bone formation.
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.
We present a new interface for interactive comparisons of more than two alternative documents in the context of a generative design system that uses generative data-flow networks defined via directed acyclic graphs. To better show differences between such networks, we emphasize added, deleted, (un)changed nodes and edges. We emphasize differences in the output as well as parameters using highlighting and enable post-hoc merging of the state of a parameter across a selected set of alternatives. To minimize visual clutter, we introduce new difference visualizations for selected nodes and alternatives using additive and subtractive encodings, which improve readability and keep visual clutter low. We analyzed similarities in networks from a set of alternative designs produced by architecture students and found that the number of similarities outweighs the differences, which motivates use of subtractive encoding. We ran a user study to evaluate the two main proposed difference visualization encodings and found that they are equally effective.
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.
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.
Integration of Multi-modal Cues in Synthetic Attention Processes to Drive Virtual Agent Behavior
(2017)
Access to affordable energy - for basic needs as well as for national economic development - is a crucial concern for developing countries. Access to modern and sustainable energy services in rural areas, where the majority of the population is living in poverty, is a particularly urgent challenge, and one which has been recognized as crucial within the global development agenda.
The current dominant development model, focused on achieving macro-economic growth, gives priority to large-scale or centralized energy infrastructures for national growth or for meeting the urban demand. Rural areas of poorer countries are often at a disadvantage in terms of access to all types of services – roads, health facilities, markets, information and clean water. The high cost of providing these services in remote areas has led to new approaches being tried, based on self-help and the private sector rather than traditional government-led solutions. The missing access to electricity is primarily the reason for the poor operational environment of entrepreneurship especially in rural areas of developing countries, which poses many barriers to their development and limits their competitiveness. Energy services for household, agriculture and production serve as best examples as sectors exposed to enable entrepreneurship by productive use of renewable energy.
This paper describes the line-up, the challenges and the outcome of a development project in rural Ethiopia to support entrepreneurship based on the usage of renewable energy, in this case mainly photo-voltaic technology. In particular, this study tries to show up key features which are required to enable sustainable energy access and foster implementation challenges of developed business models in practice. Based on this experience, the paper discusses implications and lessons learned for a further development.
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.
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.
Media development cooperation has aimed for decades at enhancing free and independent media in developing countries as well as economies in transition. Within this field of activity, the concept of media viability has gained more and more attention in recent years. This is mainly due to a proposal of UNESCO`s intergovernmental Bureau of the International Programme for the Development of Communication (IPDC). The UNESCO, in partnership with DW Akademie, has drafted a list of indicators that delineate the influencing factors of media viability for media organizations in any given country (UNESCO 2015).
As a consequence of the novelty of the media viability concept, the state of scientific research is restricted. It is frequently focused on isolated case studies without providing a scientific basis for comparison. Empirical studies and comparative analyses are limited to certain media sectors such as the print market, as well as for journalism startups and spin-offs in developed economies.
In today’s business, culture plays a vital role or to a high degree influences the attitude, perception and decision making process of an individual. Culture is an unavoidable state of rules and regulations that defines people’s daily life in a particular environment or society. There are plenty examples of business failures or stagnation or failure of joint ventures, on account of the management's inability to recognize cross-cultural challenges and tackle them appropriately.
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.
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.
Culture is at the core of any social, economic and business interactions and relationships. The way people perceive the culture of others influences their decision to collaborate socially, politically and economically with them. It is therefore, imperative students appreciate the dynamics of cross-cultural interactions and collaborations, since it exposes them to a wider view of the world. In doing this, it is important they (students) are allowed to explore as much as possible with little interference by their teachers. Using the project students went through real-life experience in a self-directed enquiry. In the process, they were taught to solve problems encountered during the learning process. The focus of the intercultural communication project was to understand how people from different cultures speak, interact and perceive others’ culture. It was found students innovate if allowed to explore a certain phenomenon on their own. Furthermore, face-to-face meetings can be arranged between people in the different countries can be arranged using these Web 2.0 tools. Based on the experience from the project, it was observed that the success of a collaborative international project depends on the understanding of the crosscultural dynamics of partners. For such collaborations, it is imperative to establish personal relationships, be flexible and adaptable to situations and change as well as being swift resolving potential conflict situation.
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.
A deployment of the Vehicle-2-Vehicle communication technology according to ETSI is in preparation in Europe. Currently, a policy for a necessary Public Key Infrastructure to enrol cryptographic keys and certificates for vehicles and infrastructure component is in discussion to enable an interoperable Vehicle-2-Vehicle communication. Vehicle-2-Vehicle communication means that vehicles periodically send Cooperative Awareness Messages. These messages contain the current geographic position, driving direction, speed, acceleration, and the current time of a vehicle. To protect privacy (location privacy, “speed privacy”) of vehicles and drivers ETSI provides a specific pseudonym concept. We show that the Vehicle-2-Vehicle communication can be misused by an attacker to plot a trace of sequent Cooperative Awareness Messages and to link this trace to a specific vehicle. Such a trace is non-disputable due to the cryptographic signing of the messages. So, the periodically sending of Cooperative Awareness Messages causes privacy problems even if the pseudonym concept is applied.
The development of fully automated vehicles is becoming more and more present in the social discussion. The image of fully automated cars is determined by automobile manufacturers and placed in the context of individual traffic. In contrast to fully autonomous private cars, fully automated public transport is already operating in some cities and is to be expanded in the future. Autonomous public transport offers great potential for the development and promotion of sustainable mobility concepts. However, the user acceptance is important for the enforcement and widespread use of these technical innovations. An online study on the acceptance of fully automated public transport based on quantitative data of a sample of N = 201 is presented. The results show a high level of familiarity with the topic and a very high level of overall intention to use fully automated public transport in the future.