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Sprachassistenten wie Alexa oder Google Assistant sind aus dem Alltag vieler VerbraucherInnen nicht mehr wegzudenken. Sie überzeugen insbesondere durch die sprachbasierte und somit freihändige Steuerung und mitunter auch den unterhaltsamen Charakter. Als häuslicher Lebensmittelpunkt sind die häufigsten Aufstellungsorte das Wohnzimmer und die Küche, da sich Haushaltsmitglieder dort die meiste Zeit aufhalten und das alltägliche Leben abspielt. Dies bedeutet allerdings ebenso, dass an diesen Orten potenziell viele Daten erfasst und gesammelt werden können, die nicht für den Sprachassistenten bestimmt sind. Demzufolge ist nicht auszuschließen, dass der Sprachassistent – wenn auch versehentlich – durch Gespräche oder Geräusche aktiviert wird und Aufnahmen speichert, selbst wenn eine Aktivierung unbewusst von Anwesenden bzw. von anderen Geräten (z. B. Fernseher) erfolgt oder aus anderen Räumen kommt. Im Rahmen eines Forschungsprojekts haben wir dazu NutzerInnen über Ihre Nutzungs- und Aufstellungspraktiken der Sprachassistenten befragt und zudem einen Prototyp getestet, der die gespeicherten Interaktionen mit dem Sprachassistenten sichtbar macht. Dieser Beitrag präsentiert basierend auf den Erkenntnissen aus den Interviews und abgeleiteten Leitfäden aus den darauffolgenden Nutzungstests des Prototyps eine Anwendung zur Beantragung und Visualisierung der Interaktionsdaten mit dem Sprachassistenten. Diese ermöglicht es, Interaktionen und die damit zusammenhängende Situation darzustellen, indem sie zu jeder Interaktion die Zeit, das verwendete Gerät sowie den Befehl wiedergibt und unerwartete Verhaltensweisen wie die versehentliche oder falsche Aktivierung sichtbar macht. Dadurch möchten wir VerbraucherInnen für die Fehleranfälligkeit dieser Geräte sensibilisieren und einen selbstbestimmteren und sichereren Umgang ermöglichen.
XML Signature Wrapping (XSW) has been a relevant threat to web services for 15 years until today. Using the Personal Health Record (PHR), which is currently under development in Germany, we investigate a current SOAP-based web services system as a case study. In doing so, we highlight several deficiencies in defending against XSW. Using this real-world contemporary example as motivation, we introduce a guideline for more secure XML signature processing that provides practitioners with easier access to the effective countermeasures identified in the current state of research.
Risk-based authentication (RBA) aims to strengthen password-based authentication rather than replacing it. RBA does this by monitoring and recording additional features during the login process. If feature values at login time differ significantly from those observed before, RBA requests an additional proof of identification. Although RBA is recommended in the NIST digital identity guidelines, it has so far been used almost exclusively by major online services. This is partly due to a lack of open knowledge and implementations that would allow any service provider to roll out RBA protection to its users. To close this gap, we provide a first in-depth analysis of RBA characteristics in a practical deployment. We observed N=780 users with 247 unique features on a real-world online service for over 1.8 years. Based on our collected data set, we provide (i) a behavior analysis of two RBA implementations that were apparently used by major online services in the wild, (ii) a benchmark of the features to extract a subset that is most suitable for RBA use, (iii) a new feature that has not been used in RBA before, and (iv) factors which have a significant effect on RBA performance. Our results show that RBA needs to be carefully tailored to each online service, as even small configuration adjustments can greatly impact RBA's security and usability properties. We provide insights on the selection of features, their weightings, and the risk classification in order to benefit from RBA after a minimum number of login attempts.
An der Hochschule Bonn-Rhein-Sieg fand am Donnerstag, den 23.9.21 das erste Verbraucherforum für Verbraucherinformatik statt. Im Rahmen der Online-Tagesveranstaltung diskutierten mehr als 30 Teilnehmer:innen über Themen und Ideen rund um den Bereich Verbraucherdatenschutz. Dabei kamen sowohl Beiträge aus der Informatik, den Verbraucher- und Sozialwissenschaften sowie auch der regulatorischen Perspektive zur Sprache. Der folgende Beitrag stellt den Hintergrund der Veranstaltung dar und berichtet über Inhalte der Vorträge sowie Anknüpfungspunkte für die weitere Konstituierung der Verbraucherinformatik. Veranstalter waren das Institut für Verbraucherinformatik an der H-BRS in Zusammenarbeit mit dem Lehrstuhl IT-Sicherheit der Universität Siegen sowie dem Kompetenzzentrum Verbraucherforschung NRW der Verbraucherzentrale NRW e. V. mit Förderung des Bundesministeriums der Justiz und für Verbraucherschutz.
Execution monitoring is essential for robots to detect and respond to failures. Since it is impossible to enumerate all failures for a given task, we learn from successful executions of the task to detect visual anomalies during runtime. Our method learns to predict the motions that occur during the nominal execution of a task, including camera and robot body motion. A probabilistic U-Net architecture is used to learn to predict optical flow, and the robot's kinematics and 3D model are used to model camera and body motion. The errors between the observed and predicted motion are used to calculate an anomaly score. We evaluate our method on a dataset of a robot placing a book on a shelf, which includes anomalies such as falling books, camera occlusions, and robot disturbances. We find that modeling camera and body motion, in addition to the learning-based optical flow prediction, results in an improvement of the area under the receiver operating characteristic curve from 0.752 to 0.804, and the area under the precision-recall curve from 0.467 to 0.549.
An der H-BRS, einer Hochschule für Angewandte Wissenschaften mit ca. 9.000 Studierenden, wurde die OER-Kultur bewusst als Teil der Strategie zur Digitalisierung der Lehre in drei Schritten etabliert: (1) Gemeinsame Strategiebildung als Teil eines partizipativ erarbeiteten Hochschulentwicklungsplans: Verankerung von OER in der Digitalisierungsstrategie. (2) Basierend auf der Vernetzung der Expertinnen und Experten erfolgreiche Einwerbung von OER-Projekten, die exemplarisch vorgestellt werden. (3) Dauerhafte strategische Verankerung, basierend auf kontinuierlicher interner und externer Netzwerkarbeit, Etablierung von digitalen Austauschplattformen für die Lehrenden, Transfer des OER-Gedankens (Kooperation, Austausch, Mehrfachnutzen) auf die Hochschuldidaktik sowie regelmäßige Ausschreibungen von Fördermaßnahmen.
The role of tourism entrepreneurship in rural development continues to be a subject of interest and debate among academia and practitioners. Theoretically, it is anticipated that tourism entrepreneurship will lead to livelihood diversification, enhancement and ultimately a revitalization of the rural economy. While tourism is posited as an accessible entrepreneurship pathway, there is a dearth of information regarding rural dwellers’ actual experiences with it, especially within the Ghanaian context. Using a case study approach and qualitative data from Wli; a rural tourism destination in Ghana, this paper delves into the opportunities and concerns associated with tourism entrepreneurship in rural areas. Data was obtained between November and December 2016 from 27 persons who were either tourism enterprise owners or employees. Findings from the study showed that entrepreneurial activities centred on the provision of accommodation, food and beverage, souvenir and guiding services. The nature of the activities enabled easy transfer of existing skills and knowledge. Further, entry into tourism entrepreneurship was perceived to be easy by the majority of study participants. These findings confirm the potential for tourism to be employed in boosting entrepreneurial activities in rural areas. Nevertheless, there were concerns regarding access to credit, institutional support, unhealthy competitions, low incomes, unguaranteed pensions, and seasonality and skewness of demand. These concerns threatened the growth and sustainability of tourism entrepreneurship within the community. From a policy perspective, there is a need for institutional recognition and support for tourism entrepreneurial intentions and activities in rural areas. Practice-wise, credit facilities need to be designed specifically for tourism-related rural enterprises. Further, periodic skills and knowledge augmentation programmes must be initiated to help expand the skill sets for the rural entrepreneurs. Finally, there is a need for the formation of traderelated networks to provide a platform for knowledge and experience sharing among the entrepreneurs.
Studies in entrepreneurship education in hospitality and tourism has indicated that further attention could be given toward helping students to develop creativity and critical thinking skills, engage in deeper self-discovery experiences, and understand tourism more fully to help prepare them for entrepreneurial roles. This study aims at evaluating Hospitality entrepreneurial modules offered in Tourism programs in Ghanaian institutions. The curriculum of Tourism in two tertiary institutions in Ghana offering Tourism is studied. The research highlights on the need to integrate hospitality technical skills into Tourism education to create a culture that will enhance the growth of entrepreneurial hospitality into Tourism as culinary Tourism is becoming common. Some of the challenges faced by tourism students and entrepreneurship educators are highlighted. Structured interview technique was used to collect data from 20 purposive sampled students of the selected institutions. The results revealed that the level of importance and attention given to hospitality skills in tourism and the perception of students on acquisition of the required competencies is minimal. It is therefore recommended that more skills and competences in hospitality operation, food and beverage production and service be introduced in tourism education in a more holistic manner with emphasis on skill acquisition in order to make the tourism graduate more creative and critical thinker in today’s global competitive environment.
Rural Social Entrepreneurship (RSE) is considered an essential factor for achieving Sustainable Rural Development (SRD) and improving rural people's socio-economic status through increasing production, productivity, reducing unemployment, and accelerating the progress in achieving SDGs. The paper aims at examining the role of social entrepreneurship in achieving (SRD) in Sudan with reference to Wad Balal Project for investment and rural development in Gezira State, which established in 2005 in small villages in Gezira State through mobilizing of local savings and resources for creating job opportunities, sponsoring poor households, improving the infrastructures, and reducing poverty. The study depends on cross-sectional data collected through a questionnaire and focus group discussion from 100 head of households in the village under research. A questionnaire is internally consistent, and its questions are stable. Frequencies and percentages have been used for describing the basic characteristics of the respondents. Statistical t-test was adopted to test the opinions of respondents about the role of the project based on the Likert scale. The results revealed that the project has significantly increased the opportunities of job and training as well as household income, the results also confirmed that the project has improved the status of education and health services in the village. The project has extended and established many branches; the project also diversified its investment to cover more kinds of investments, the project reinvested 50% of its profits and directed the rest to charity, and social services in the village, many lessons can be learned from the project story. The research recommended that a similar social entrepreneurship project can be generalized to more villages in Sudan and other developing countries to accelerate sustainable rural development. Local communities have to support similar initiatives for developing their villages.
New communication technologies are changing the way we work and communicate with people around the world. Given this reality, students in Higher Education (HE) worldwide need to develop knowledge in their area of study as well as attitudes and values that will enable them to be responsible and ethical global citizens in the workforce they will soon enter, regardless of the degree. Different institutional and country-specific requirements are important factors when developing an international Virtual Exchange (VE) program. Digital learning environments such as ProGlobe – Promoting the Global Exchange of Ideas on Sustainable Goals, Practices, and Cultural Diversity – offer a platform for collaborating with diverse students around the world to share and reflect on ideas on sustainable practices. Students work together virtually on a joint interdisciplinary project that aims to create knowledge and foster cultural diversity. This project was successfully integrated into each country’s course syllabus through a common global theme; sustainability. The focus of this paper is to present multi-disciplinary perspectives on the opportunities and challenges in implementing a VE project in HE. Furthermore, it will present the challenges that country coordinators dealt with when planning and implementing their project. Given the disparity found in each course syllabus, project coordinators uniquely handled the project goal, approach, and assessment for their specific course and program. Not only did the students and faculty gain valuable insight into different aspects of collaboration when working in interdisciplinary HE projects, they also reflected on their own impact on the environment and learned to listen to how people in different countries deal with environmental issues. This approach provided students with meaningful intercultural experiences that helped them link ideas and concepts about a global issue through the lens of their own discipline as well as other disciplines worldwide.
In this paper, the electrochemical alkaline methanol oxidation process, which is relevant for the design of efficient fuel cells, is considered. An algorithm for reconstructing the reaction constants for this process from the experimentally measured polarization curve is presented. The approach combines statistical and principal component analysis and determination of the trust region for a linearized model. It is shown that this experiment does not allow one to determine accurately the reaction constants, but only some of their linear combinations. The possibilities of extending the method to additional experiments, including dynamic cyclic voltammetry and variations in the concentration of the main reagents, are discussed.
Start-ups als Arbeitgeber
(2021)
In den Atmosphärenwissenschaften spielt die Strahlungsbilanz der Erde eine wichtige Rolle für unser Verständnis des Klimasystems. Hier liefern ausgereifte Satellitenprodukte dekadische Klimazeitreihen mit einer so hohen Genauigkeit, dass z.B. Änderungen im Zusammenhang mit dem Klimawandel detektiert werden können. Dies gilt insbesondere auch für die solaren Strahlungsflüsse an der Erdoberfläche. Beim Vergleich dieser Satellitenprodukte mit instantanen Beobachtungen der Strahlung am Erdboden sind jedoch oft erhebliche Abweichungen feststellbar, die hauptsächlich durch kleinskalige Variabilität in der räumlichen Struktur von Wolken und ihrer Strahlungswirkung verursacht werden. Hier ist auch zu bedenken, dass Bodenbeobachtungen fast einer Punktmessung entsprechen, während Satellitenpixel eine Fläche in der Größenordnung von Quadratkilometern abtasten.
Since stationary self-checkout is widely introduced and well understood, previous research barely examined newer generations of smartphone-based Scan&Go. Especially from a design perspective, we know little about the factors contributing to the adoption of Scan&Go solutions and how design enables consumers to take full advantage of this development rather than being burdened with using complex and unenjoyable systems. To understand the influencing factors and the design from a consumer perspective, we conducted a mixed-methods study where we triangulated data of an online survey with 103 participants and a qualitative study with 20 participants. Based on the results, our study presents a refined and nuanced understanding of technology as well as infrastructure-related factors that influence adoption. Moreover, we present several implications for designing and implementing of Scan&Go in retail environments.
Robot Action Diagnosis and Experience Correction by Falsifying Parameterised Execution Models
(2021)
When faced with an execution failure, an intelligent robot should be able to identify the likely reasons for the failure and adapt its execution policy accordingly. This paper addresses the question of how to utilise knowledge about the execution process, expressed in terms of learned constraints, in order to direct the diagnosis and experience acquisition process. In particular, we present two methods for creating a synergy between failure diagnosis and execution model learning. We first propose a method for diagnosing execution failures of parameterised action execution models, which searches for action parameters that violate a learned precondition model. We then develop a strategy that uses the results of the diagnosis process for generating synthetic data that are more likely to lead to successful execution, thereby increasing the set of available experiences to learn from. The diagnosis and experience correction methods are evaluated for the problem of handle grasping, such that we experimentally demonstrate the effectiveness of the diagnosis algorithm and show that corrected failed experiences can contribute towards improving the execution success of a robot.
Over the last decades, different kinds of design guides have been created to maintain consistency and usability in interactive system development. However, in the case of spatial applications, practitioners from research and industry either have difficulty finding them or perceive such guides as lacking relevance, practicability, and applicability. This paper presents the current state of scientific research and industry practice by investigating currently used design recommendations for mixed reality (MR) system development. We analyzed and compared 875 design recommendations for MR applications elicited from 89 scientific papers and documentation from six industry practitioners in a literature review. In doing so, we identified differences regarding four key topics: Focus on unique MR design challenges, abstraction regarding devices and ecosystems, level of detail and abstraction of content, and covered topics. Based on that,we contribute to the MR design research by providing three factors for perceived irrelevance and six main implications for design recommendations that are applicable in scientific and industry practice.
Representation and Experience-Based Learning of Explainable Models for Robot Action Execution
(2021)
For robots acting in human-centered environments, the ability to improve based on experience is essential for reliable and adaptive operation; however, particularly in the context of robot failure analysis, experience-based improvement is only useful if robots are also able to reason about and explain the decisions they make during execution. In this paper, we describe and analyse a representation of execution-specific knowledge that combines (i) a relational model in the form of qualitative attributes that describe the conditions under which actions can be executed successfully and (ii) a continuous model in the form of a Gaussian process that can be used for generating parameters for action execution, but also for evaluating the expected execution success given a particular action parameterisation. The proposed representation is based on prior, modelled knowledge about actions and is combined with a learning process that is supervised by a teacher. We analyse the benefits of this representation in the context of two actions – grasping handles and pulling an object on a table – such that the experiments demonstrate that the joint relational-continuous model allows a robot to improve its execution based on experience, while reducing the severity of failures experienced during execution.
In the course of growing online retailing, recommendation systems have become established that derive recommendations from customers’ purchase histories. Recommending suitable food products can represent a lucrative added value for food retailers, but at the same time challenges them to make good predictions for repeated food purchases. Repeat purchase recommendations have been little explored in the literature. These predict when a product will be purchased again by a customer. This is especially important for food recommendations, since it is not the frequency of the same item in the shopping basket that is relevant for determining repeat purchase intervals, but rather their difference over time. In this paper, in addition to critically reflecting classical recommendation systems on the underlying repeat purchase context, two models for online product recommendations are derived from the literature, validated and discussed for the food context using real transaction data of a German stationary food retailer.
Property-Based Testing in Simulation for Verifying Robot Action Execution in Tabletop Manipulation
(2021)
An important prerequisite for the reliability and robustness of a service robot is ensuring the robot’s correct behavior when it performs various tasks of interest. Extensive testing is one established approach for ensuring behavioural correctness; this becomes even more important with the integration of learning-based methods into robot software architectures, as there are often no theoretical guarantees about the performance of such methods in varying scenarios. In this paper, we aim towards evaluating the correctness of robot behaviors in tabletop manipulation through automatic generation of simulated test scenarios in which a robot assesses its performance using property-based testing. In particular, key properties of interest for various robot actions are encoded in an action ontology and are then verified and validated within a simulated environment. We evaluate our framework with a Toyota Human Support Robot (HSR) which is tested in a Gazebo simulation. We show that our framework can correctly and consistently identify various failed actions in a variety of randomised tabletop manipulation scenarios, in addition to providing deeper insights into the type and location of failures for each designed property.
Recent publications propose concepts of systems that integrate the various services and data sources of everyday food practices. However, this research does not go beyond the conceptualization of such systems. Therefore, there is a deficit in understanding how to combine different services and data sources and which design challenges arise from building integrated Household Information Systems. In this paper, we probed the design of an Integrated Household Information System with 13 participants. The results point towards more personalization, automatization of storage administration and enabling flexible artifact ecologies. Our paper contributes to understanding the design and usage of Integrated Household Information Systems, as a new class of information systems for HCI research.
Das Kernanliegen des Datenschutzes ist es, natürliche Personen vor nachteiligen Effekten der Speicherung und Verarbeitung der sie betreffenden Daten zu schützen. Aber viele Personen scheinen gar nicht geschützt werden zu wollen. Im Gegenteil, viele Endanwender willigen “freiwillig“ – bewusst oder unbewusst – in eine umfassende Verarbeitung ihrer personenbezogenen Daten ein. Warum tun Menschen dies? Es werden verschiedene Ursachen diskutiert (beispielsweise in [79]), hierzu gehören Uninformiertheit, mangelnde Sensibilität, das Gefühl der Hilflosigkeit, mangelnde Zahlungsbereitschaft und mangelnde Alternativen. Auch wenn dies in Einzelfällen zutrifft, so gibt es oft sehr wohl datenschutzfreundliche Alternativen. Beispielsweise existiert zu WhatsApp (als Instant Messaging App) die Alternative Threema. Threema gilt als EU-DS-GVO-konform und funktional durchaus mit WhatsApp vergleichbar [62]. Allerdings ist inzwischen die aktuelle Netzwerkgröße ein entscheidendes Auswahlkriterium: Im Januar 2018 hatte Threema 4,5 Millionen Nutzer [172], WhatsApp dagegen 1,5 Milliarden [171]. Dies ist ein Indiz dafür, dass WhatsApp sich quasi zum De-facto-Standard entwickelt hat und es für die einzelne Person nur schwer möglich ist, viele andere “zum Wechsel auf ein anderes Produkt zu bewegen. [. . . ] Bei Diensten mit Nutzerzahlen im Milliardenbereich kann von ’Freiwilligkeit’ nur noch bedingt gesprochen werden.“ [9]
Risk-based authentication (RBA) extends authentication mechanisms to make them more robust against account takeover attacks, such as those using stolen passwords. RBA is recommended by NIST and NCSC to strengthen password-based authentication, and is already used by major online services. Also, users consider RBA to be more usable than two-factor authentication and just as secure. However, users currently obtain RBA's high security and usability benefits at the cost of exposing potentially sensitive personal data (e.g., IP address or browser information). This conflicts with user privacy and requires to consider user rights regarding the processing of personal data. We outline potential privacy challenges regarding different attacker models and propose improvements to balance privacy in RBA systems. To estimate the properties of the privacy-preserving RBA enhancements in practical environments, we evaluated a subset of them with long-term data from 780 users of a real-world online service. Our results show the potential to increase privacy in RBA solutions. However, it is limited to certain parameters that should guide RBA design to protect privacy. We outline research directions that need to be considered to achieve a widespread adoption of privacy preserving RBA with high user acceptance.
In view of the rapid growth of solar power installations worldwide, accurate forecasts of photovoltaic (PV) power generation are becoming increasingly indispensable for the overall stability of the electricity grid. In the context of household energy storage systems, PV power forecasts contribute towards intelligent energy management and control of PV-battery systems, in particular so that self-sufficiency and battery lifetime are maximised. Typical battery control algorithms require day-ahead forecasts of PV power generation, and in most cases a combination of statistical methods and numerical weather prediction (NWP) models are employed. The latter are however often inaccurate, both due to deficiencies in model physics as well as an insufficient description of irradiance variability.
In Robot-Assisted Therapy for children with Autism Spectrum Disorder, the therapists’ workload is increased due to the necessity of controlling the robot manually. The solution for this problem is to increase the level of autonomy of the system, namely the robot should interpret and adapt to the behaviour of the child under therapy. The problem that we are adressing is to develop a behaviour model that will be used for the robot decision-making process, which will learn how to adequately react to certain child reactions. We propose the use of the reinforcement learning technique for this task, where feedback for learning is obtained from the therapist’s evaluation of a robot’s behaviour.
Personal values and electronic waste disposal behaviours among households in Cape Coast Metropolis
(2021)
The study examined social values that accounted for electronic waste recycling and reuse behaviours. Via a crosscommunity survey of 193 of households in the Cape Coast Metropolis, a correlational design was employed in the study. Partial Least Squares-Structural equation modelling was used to analyse the data. Results from the analysis showed the influence of altruistic values (β = 0.275, p < 0.05) on reuse behaviour. Similarly, environmental awareness (β = 0.213, p<0.05) also showed significant influence on participation in recycling, whereas psychological ownership significantly influenced both reuse (β = 0.319, p < 0.05), and participation in recycling (β = 0.339, p < 0.05), The joint significance of altruistic values, environmental awareness and psychological ownership to explaining recycling participation was 21.3% (R2 = 0.213, p < 0.05) and that of reuse was 24.6% (R2 = 0.246, p < 0.05). The results of the study showed that individuals who are knowledgeable about the state of their environment were more likely to participate in recycling. On the other hand, individuals with altruistic values preferred giving unwanted electronic equipment to others for reuse. Altruistic values are particularly true of collectivist cultural orientation. Psychological ownership was significant in predicting both behaviours, however, the effect size on reuse was moderate. Psychological ownership due to waste aversion and frugality lead consumers to keep, and subsequently give to close relatives in their social network. It was recommended that individuals should be encouraged to patronize formal recycling services. as a way to show concern for the well-being of others by reducing pollution due to improper waste treatment. Again, like in developed economies, second-hand collection systems for unwanted electronic products can be developed, and made convenient for individuals with reusable items, who may be willing to donate or even resell.
There is severe clinical vitamin A deficiency (VAD) prevalence among Ghanaians and many African countries. Foodbased diets has been suggested as a more sustainable approach to solving the VAD situation in Africa. In this study, A participatory action research between orange flesh sweet potato farmers, gari processors within central region and academia was adopted to develop gari containing provitamin A beta-carotene. Gari is a major staple for Ghanaians and people in the West African subregion due to its affordability and swelling capacity. It is mainly eaten raw with water, sugar, groundnut and milk as gari-soakings or with hot water to prepare gelatinized food called gari-kai in Ghana or “eba” among Nigerians. However, gari is limited in provitamin A carotenoids. Orange fleshed sweet potato (OFSP) is known to contain large amount of vitamin A precursor. Therefore, addition of OFSP to gari would have the potential to fight the high prevalence rate of vitamin A deficiency amongst less developed regions of Africa. To develop this, different proportions of orange fleshed sweet potatoes (OFSP) was used to substitute cassava mash and fermented spontaneously to produce composite gari - a gritty-crispy ready-to-eat food product. Both the amount of OFSP and the fermentation duration caused significant increases in the β-carotene content of the composite gari. OFSP addition reduced the luminance while roasting made the composite gari yellower when compared with the cake used. Addition of OFSP negatively affected the swelling capacity of the gari although not significant. The taste, texture, flavour and the overall preferences for the composite gari decreased due to the addition of the OFSP but fermentation duration (FD) improved them. The sample with 10% OFSP and FD of 1.81 days was found to produce the optimal gari. One-portion of the optimal gari would contribute to 34.75, 23.2, 23.2, 27, 17 and 16% of vitamin A requirements amongst children, adolescent, adult males, adult females, pregnant women and lactating mothers respectively. The study demonstrated that partial substitution of cassava with OFSP for gari production would have the potential to fight the high prevalence rate of vitamin A deficiency amongst less developed regions of Africa while involvement of farmers and processors prior to the design of research phase enhanced the adoption of intervention strategies.
Open-Source Software spielt sowohl zur Ausgestaltung von Lehr- und Lernszenarien (bspw. Organisation mit Editoren und Groupware, Kollaboration und Kommunikation via Chats und Webblogs), als auch für die Umsetzung von Forschunsprojekten (zum Beispiel Auswertung großer Datenbestände, Erprobung realer Situationen in vituellen Laboren, Evaluation neuer Oberflächenentwicklungen) eine wichtige Rolle. Um eine bestmögliche Passung der Software herzustellen, erfolgt Softwareentwicklung im Hochschulbereich entweder forschungsprojektbezogen oder Disziplin- und Einrichtungsübergreifend.
Experience made with free and open source software (FOSS) in the public research is shared with the community. The motivation for using and publishing FOSS is to increase visibility, transparancy and feedback quality while at the same time lowering software licensing costs. Also, the idea of giving back and returning a value plays a role. The most frequently given counter arguments are discussed. In the end, it’s important to embed FOSS publishing into the company’s strategy for the exploitation of scientific research results. To help with this, a checklist of criteria to indicate FOSS publishing is suggested. On the backround of wireless sensor networks, some case studies of FOSS contribution are detailed. The emphasis is on checking the original motivation and the spirit of FOSS back with the reality. Finally, further potential of publishing FOSS in the context of scientific research is identified.
When an autonomous robot learns how to execute actions, it is of interest to know if and when the execution policy can be generalised to variations of the learning scenarios. This can inform the robot about the necessity of additional learning, as using incomplete or unsuitable policies can lead to execution failures. Generalisation is particularly relevant when a robot has to deal with a large variety of objects and in different contexts. In this paper, we propose and analyse a strategy for generalising parameterised execution models of manipulation actions over different objects based on an object ontology. In particular, a robot transfers a known execution model to objects of related classes according to the ontology, but only if there is no other evidence that the model may be unsuitable. This allows using ontological knowledge as prior information that is then refined by the robot’s own experiences. We verify our algorithm for two actions – grasping and stowing everyday objects – such that we show that the robot can deduce cases in which an existing policy can generalise to other objects and when additional execution knowledge has to be acquired.
Frequently the main purpose of domestic artifacts equipped with smart sensors is to hide technology, like previous examples of a Smart Mirror show. However, current Smart Homes often fail to provide meaningful IoT applications for all residents’ needs. To design beyond efficiency and productivity, we propose to realize the potential of the traditional artifact for calm and engaging experiences. Therefore, we followed a design case study approach with 22 participants in total. After an initial focus group, we conducted a diary study to examine home routines and developed a conceptual design. The evaluation of our mid-fidelity prototype shows, that we need to study carefully the practices of the residents to leverage the physical material of the artifact to fit the routines. Our Smart Mirror, enhanced by digital qualities, supports meaningful activities and makes the bathroom more appealing. Thereby, we discuss domestic technology design beyond automation.
Kenya as a touristic destination is well known as an exotic country offering many different landscapes as well as the diversity of wildlife; this is typical for several African countries. To ensure a sustainable tourism development, different forms of tourism have to be considered. One of these forms could be eco-mountain bike cycling tours, as these tours are gaining in popularity, for example in Germany. The aim of this study was to obtain results regarding the market potential for mountain bike eco-tourism in Kenya. The up-and-coming tourism branch of mountain biking was examined in connection with the increasing demand for long-distance travel. The results of this study showed that mountain biking in exotic countries like Kenya has market potential in principle. However, it was also found that mountain biking alone is not a sufficient pull factor for tourists. The combination with other activities turned out to be promising. It was found that tourist packages that include mountain biking as an activity are perceived as attractive. Moreover, it was obtained that not only tourists who ride a mountain bike regularly are addressed as a target group. Even "regular" tourists find mountain biking an attractive (touristic) activity, especially in combination with game drives. Experts also assess the market potential for eco-mountain bike tourism as positive and find existing routes and accommodation attractive. The findings are giving indications for the possibilities to develop eco-mountain bike tourism as a touristic alternative and addition to existing touristic products.
Low-Cost In-Hand Slippage Detection and Avoidance for Robust Robotic Grasping with Compliant Fingers
(2021)
Less is Often More: Header Whitelisting as Semantic Gap Mitigation in HTTP-Based Software Systems
(2021)
The web is the most wide-spread digital system in the world and is used for many crucial applications. This makes web application security extremely important and, although there are already many security measures, new vulnerabilities are constantly being discovered. One reason for some of the recent discoveries lies in the presence of intermediate systems—e.g. caches, message routers, and load balancers—on the way between a client and a web application server. The implementations of such intermediaries may interpret HTTP messages differently, which leads to a semantically different understanding of the same message. This so-called semantic gap can cause weaknesses in the entire HTTP message processing chain.
In this paper we introduce the header whitelisting (HWL) approach to address the semantic gap in HTTP message processing pipelines. The basic idea is to normalize and reduce an HTTP request header to the minimum required fields using a whitelist before processing it in an intermediary or on the server, and then restore the original request for the next hop. Our results show that HWL can avoid misinterpretations of HTTP messages in the different components and thus prevent many attacks rooted in a semantic gap including request smuggling, cache poisoning, and authentication bypass.
Konzept zum Umgang mit Prüfungsstress und Lernblockaden bei Studierenden in der Studieneingangsphase
(2021)
In times of climatic or political grievances that affect not only human life worldwide, but also the environment and the economic situation of a country, a change in the way of thinking about tourism is beginning and the sector of ecotourism is also becoming increasingly important in Germany. The applicability of this form of tourism in the East African destination Kenya in the form of a travel package that is both partly unique and can be designed individually describes the subject matter of this elaboration and is illustrated using the example of the charitable organization Mully Children's Family and the related registered tourism company, MCF Africa Safaris. The underlying research aims to determine how to transform the organisation's own tree planting initiative into a niche tourist market and how this must be geared to gain the interest of the German eco-tourist. Based on the evaluation of the research results, there is high potential, which is dedicated to the implementation of a form of travel consisting of the active support of the named charity and its initiative as well as individually selectable holiday activities in the target market Kenya. As a result, there are basic prerequisites, the consideration of which is essential for the successful integration of the so-called niche market tree planting and the branch-specific nature of ecotourism in the Kenyan travel market.