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„from stable to table“
(2008)
Along with the success of the digitally revived stereoscopic cinema, other events beyond 3D movies become attractive for movie theater operators, i.e. interactive 3D games. In this paper, we present a case that explores possible challenges and solutions for interactive 3D games to be played by a movie theater audience. We analyze the setting and showcase current issues related to lighting and interaction. Our second focus is to provide gameplay mechanics that make special use of stereoscopy, especially depth-based game design. Based on these results, we present YouDash3D, a game prototype that explores public stereoscopic gameplay in a reduced kiosk setup. It features live 3D HD video stream of a professional stereo camera rig rendered in a real-time game scene. We use the effect to place the stereoscopic effigies of players into the digital game. The game showcases how stereoscopic vision can provide for a novel depth-based game mechanic. Projected trigger zones and distributed clusters of the audience video allow for easy adaptation to larger audiences and 3D movie theater gaming.
YAWL User Group
(2012)
YAWL Symposium 2013. Proceedings of the First YAWL Symposium, Sankt Augustin, Germany, June 7, 2013
(2013)
XML Encryption and XML Signature are fundamental security standards forming the core for many applications which require to process XML-based data. Due to the increased usage of XML in distributed systems and platforms such as in SOA and Cloud settings, the demand for robust and effective security mechanisms increased as well. Recent research work discovered, however, substantial vulnerabilities in these standards as well as in the vast majority of the available implementations. Amongst them, the so-called XML Signature Wrapping attack belongs to the most relevant ones. With the many possible instances of this attack type, it is feasible to annul security systems relying on XML Signature and to gain access to protected resources as has been successfully demonstrated lately for various Cloud infrastructures and services. This paper contributes a comprehensive approach to robust and effective XML Signatures for SOAP-based Web Services. An architecture is proposed, which integrates the r equired enhancements to ensure a fail-safe and robust signature generation and verification. Following this architecture, a hardened XML Signature library has been implemented. The obtained evaluation results show that the developed concept and library provide the targeted robustness against all kinds of known XML Signature Wrapping attacks. Furthermore the empirical results underline, that these security merits are obtained at low efficiency and performance costs as well as remain compliant with the underlying standards.
In this paper, we present XPERSim, a 3D simulator built on top of open source components that enables users to quickly and easily construct an accurate and photo-realistic simulation for robots of arbitrary morphology and their environments. While many existing robot simulators provide a good dynamics simulation, they often lack the high quality visualization that is now possible with general-purpose hardware. XPERSim achieves such visualization by using the Object-Oriented Graphics Rendering Engine 3D (Ogre) engine to render the simulation whose dynamics are calculated using the Open Dynamics Engine (ODE). Through XPERSim’s integration into a component-based software integration framework used for robotic learning by experimentation, XPERSIF, and the use of the scene-oriented nature of the Ogre engine, the simulation is distributed to numerous users that include researchers and robotic components, thus enabling simultaneous, quasi-realtime observation of the multiple-camera simulations.
This paper describes a codesign environment based on the WWW (World Wide Web) and its implementation. Tool invocations and their respective results are linked using hypertext documents. We show how to configure a WWW browser for spawning design tools and how frequent tasks like documentation generation and retrieval are facilitated. The design flow can be adopted to the given application very easily. In addition we introduce the concept of a work flow called ‘design by documentation’. A WWW link to the results is given and experience using it in a codesign project is described.
Routing Attacks are a serious threat to communication in tactical MANETs. TOGBAD is a centralised approach, using topology graphs to detect such attacks. In this paper, we present TOGBAD's newly added wormhole detection capability. It is an adaptation of a wormhole detection method developed by Hu et al. This method is based on nodes' positions. We adapted it to the specific properties of tactical environments. Furthermore, we present simulation results which show TOGBAD's performance regarding the detection of wormhole attacks.
In order to help journalists investigate inside large audiovisual archives, as maintained by news broadcast agencies, the multimedia data must be indexed by text-based search engies. By automatically creating a transcript through automatic speech recognition (ASR), the spoken word becomes accessible to text search, and queries for keywords are made possible. But stil, important contextual information like the identity of the speaker is not captured. Especially when gathering original footage in the political domain, the identity of the speaker can be the most important query constraint, although this name may not be prominent in the words spoken. It is thus desireable to have this information provided explicitely to the search engine. To provide this information, the archive must be an alyzed by automatic Speaker Identification (SID). While this research topic has seen substantial gains in accuracy and robustness over last years, it has not yet established itself as a helpful, large-scale tool outside the research community. This thesis sets out to establish a workflow to provide automatic speaker identification. Its application is to help journalists searching on speeches given in the German parliament (Bundestag). This is a contribution to the News-Stream 3.0 project, a BMBF funded research project that addresses accessibility of various data sources for journalists.
The paper presents a new control strategy of management of transport companies operating in completive transport environment. It is aimed to optimise the headway of transport companies to provide the balance between costs and benefits of operation under competition. The model of transport system build using AnyLogic comprises agent-based and discrete-event techniques. The model combined two transport companies was investigated under condition of the competition between them. It was demonstrated that the control strategy can ensure the balance of interests of transport companies trying to find compromise between cost of operation and quality of service.
Work in progress: Starter-project for first semester students to survey their engineering studies
(2015)
In this contribution, we describe the activities and promotion programs installed at the Bonn-Rhein-Sieg University as an institution and at the Department of Computer Science respectively for increasing the total number of computer science students and in particular the female rate. We report about our experiences in addressing gender aspects in education and try to evaluate the outcome of our programs with respect to our equal rights for women strategy. We propose a closer look at mental self-theories enabled by E-portfolios to address also gender issues in Computer Science. Moreover, reasons are identified and discussed which may be responsible for the reduced interest in particular of female young adults to choose a computer science study program.
The ability to breathe air represents a fundamental step in vertebrate evolution that was accompanied by several anatomical and physiological adaptations. The morphology of the air-blood barrier is highly conserved within air-breathing vertebrates. It is formed by three different plies, which are represented by the alveolar epithelium, the basal lamina, and the endothelial layer. Besides these conserved morphological elements, another common feature of vertebrate lungs is that they contain a certain amount of fluid that covers the alveolar epithelium. The volume and composition of the alveolar fluid is regulated by transepithelial ion transport mechanisms expressed in alveolar epithelial cells. These transport mechanisms have been reviewed extensively. Therefore, the present review focuses on the properties and functional significance of the alveolar fluid. How does the fluid enter the alveoli? What is the fate of the fluid in the alveoli? What is the function of the alveolar fluid in the lungs? The review highlights the importance of the alveolar fluid, its volume and its composition. Maintenance of the fluid volume and composition within certain limits is critical to facilitate gas exchange. We propose that the alveolar fluid is an essential element of the air-blood barrier. Therefore, it is appropriate to refer to this barrier as being formed by four plies, namely (1) the thin fluid layer covering the apical membrane of the epithelial cells, (2) the epithelial cell layer, (3) the basal membrane, and (4) the endothelial cells.
Who do you trust: Peers or Technology? A conjoint analysis about computational reputation mechanisms
(2020)
Peer-to-peer sharing platforms are taking over an increasingly important role in the platform economy due to their sustainable business model. By sharing private goods and services, the challenge arises to build trust between peers online mostly without any kind of physical presence. Peer rating has been proven as an important mechanism. In this paper, we explore the concept called Trust Score, a computational rating mechanism adopted from car telematics, which can play a similar role in carsharing. For this purpose, we conducted a conjoint analysis where 77 car owners chose between fictitious user profiles. Our results show that in our experiment the telemetric-based score slightly outperforms the peer rating in the decision process, while the participants perceived the peer rating more helpful in retrospect. Further, we discuss potential benefits with regard to existing shortcomings of user rating, but also various concerns that should be considered in concepts like telemetric-based reputation mechanism that supplements existing trust factors such as user ratings.
In education, finding the appropriate learning pace that fits to the members of a large group is a challenging task. This becomes especially evident when teaching multidisciplinary subjects such as epidemiology in medicine or computer science in most study programs, since lecturers have to face a very heterogeneous state of previous knowledge. Approaching this issue requires an individual supervision of each and every student, which is obviously bounded by the available resources. Moreover, when referring back to the second example, writing computer programs requires a complex installation and configuration of development tools. Many beginning programmers already become stuck at this entry stage. This paper introduces WHELP, a Web-based Holistic E-Learning Platform, which provides an integrated environment enabling the learning and teaching of computer science topics without the need to install any software. Moreover, WHELP includes an interactive feedback system for each programming exercise, where lecturers or tutors can supply comments, improvements, code assistance or tips helping the students to accomplish their tasks. Furthermore, WHELP offers a statistical analysis module as well as a real-time classroom polling system both promoting an overview of the state of knowledge of a course. In addition to that, WHELP enables collaborative working including code-sharing and peer-to-peer learning. This feature enables students to work on exercises simultaneously at distinct places. WHELP has been successfully deployed in the winter term 2013 at the Cologne University of Applied Sciences supporting the 120 students and 3 lecturers to learn and teach basic topics of computer science in an engineering study program.
This paper aspires to develop a deeper understanding of the sharing/collaborative/platform economy, and in particular of the technical mechanisms upon which the digital platforms supporting it are built. In surveying the research literature, the paper identifies a gap between studies from economical, social or socio-technical angles, and presentations of detailed technical solutions. Most cases study larger, ‘monotechnological’ platforms, rather than local platforms that lend components from several technologies. Almost no literature takes a design perspective. Rooted in Sharing & Caring, an EU COST Action (network), the paper presents work to systematically map out functionalities across domains of the sharing economy. The 145 technical mechanisms we collected illustrate how most platforms are depending on a limited number of functionalities that lack in terms of holding communities together. The paper points to the necessity of a better terminology and concludes by discussing challenges and opportunities for the design of future and more inclusive platforms.
What is Design Theory?
(2021)
Smart home systems change the way we experience the home. While there are established research fields within HCI for visualizing specific use cases of a smart home, studies targeting user demands on visualizations spanning across multiple use cases are rare. Especially, individual data-related demands pose a challenge for usable visualizations. To investigate potentials of an end-user development (EUD) approach for flexibly supporting such demands, we developed a smart home system featuring both pre-defined visualizations and a visualization creation tool. To evaluate our concept, we installed our prototype in 12 households as part of a Living Lab study. Results are based on three interview studies, a design workshop and system log data. We identified eight overarching interests in home data and show how participants used pre-defined visualizations to get an overview and the creation tool to not only address specific use cases but also to answer questions by creating temporary visualizations.
Application systems are often advertised with features, and features are used heavily for requirements man- agement. However, often software manufacturers only have incomplete information about the features of their software. The information is distributed over different sources, such as requirements documents, issue trackers, user manuals, and code. In this paper, we research the occurrence of feature information in open source software engineering data. We report on a case study with three open source systems. We analyze what information about features can be found in issue trackers and user documentation. Furthermore, we study the abstraction levels on which the features are described, how feature information is related, and we discuss the possibility to discover such information semi-automatically. To mirror the diversity of software development contexts, we choose open source systems, which are quite different, e.g., in the rigor of issue tracker usage. The results differ accordingly. One main result is that the user documentation did not provide more accurate information than the issue tracker compared to a provided feature list. The results also give hints on how the management of feature relevant information can be supported.
Web-based Editor for YAWL
(2013)
This paper presents a web-based editor that offers YAWL editing capabilities and comprehensive support for the XML format of YAWL. The open-source project Signavio Core Components is extended with a graphical user interface (GUI) for parts of the YAWL Language, and an import-/export component that converts between YAWL and the internal format of Signavio Core Components. This conversion, between the web-based editor and the offcial YAWL Editor, is lossless so both tools may be used together. Compared to the offcial YAWL Editor, the web-based editor is missing some features, but could still facilitate the usage of the YAWL system in use cases that are not supported by a desktop application.
Software development is a complex task. Merely focussing on functional requirements is not sufficient any more. Developers are responsible to take many non-functional requirements carefully into account. Security is amongst the most challenging, as getting it wrong will result in a large user-base being potentially at risk. A similar situation exists for administrators. Security defaults have been put into place here to encounter lacking security controls. As first attempts to establish security by default in software development are flourishing, the question on their usability for developers arises.
In this paper we study the effectiveness and efficiency of Content Security Policy (CSP) enforced as security default in a web framework. When deployed correctly, CSP is a valid protection mean in a defence-in-depth strategy against code injection attacks. In this paper we present a first qualitative laboratory study with 30 participants to discover how developers deal with CSP when deployed as security default. Our results emphasize that the deployment as security default has its benefits but requires careful consideration of a comprehensive information flow in order to improve and not weaken security. We provide first insights to inform research about aiding developers in the creation of secure web applications with usable security by default.
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.
Nowadays Field Programmable Gate Arrays (FPGA) are used in many fields of research, e.g. to create prototypes of hardware or in applications where hardware functionality has to be changed more frequently. Boolean circuits, which can be implemented by FPGAs are the compiled result of hardware description languages such as Verilog or VHDL. Odin II is a tool, which supports developers in the research of FPGA based applications and FPGA architecture exploration by providing a framework for compilation and verification. In combination with the tools ABC, T-VPACK and VPR, Odin II is part of a CAD flow, which compiles Verilog source code that targets specific hardware resources. This paper describes the development of a graphical user interface as part of Odin II. The goal is to visualize the results of these tools in order to explore the changing structure during the compilation and optimization processes, which can be helpful to research new FPGA architectures and improve the workflow.
In this contribution a machine vision inspection system is presented which is designed as a length measuring sensor. It is developed to be applied to a range of heat shrink tubes, varying in length, diameter and color. The challenges of this task were the precision and accuracy demands as well as the real-time applicability of the entire approach since it should be realized in regular industrial line production. In production, heat shrink tubes are cut to specific sizes from a continuous tube. A multi-measurement strategy has been developed, which measures each individual tube segment several times with sub pixel accuracy while being in the visual field. The developed approach allows for a contact-free and fully automatic control of 100% of produced heat shrink tubes according to the given requirements with a measuring precision of 0.1mm. Depending on the color, length and diameter of the tubes considered, a true positive rate of 99.99% to 100% has been reached at a true negative rate of > 99.7.
Virtuelle Umgebungen
(2000)
Virtual exchange
(2022)
Dementia not only affects the cognitive capabilities, especially memory and orientation, but also physical capabilities, which are associated with a decrease of physical activities. Here, ICT can play a major role to improve health, quality of life and wellbeing in older adults suffering from dementia and related stakeholders, such as relatives, professional and informal caregivers. The aim of the presented system is to increase physical and cognitive capabilities of people with dementia and their caregivers to support them in daily life activities, reduce the strain of the caregivers and improve both their wellbeing.
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.
The Fifth International Conference on Advances in Vehicular Systems, Technologies and Applications (VEHICULAR 2016), held between November 13-17, 2016 - Barcelona, Spain, continued the inaugural event considering the state-of-the-art technologies for information dissemination in vehicle-to-vehicle and vehicle-to-infrastructure and focusing on advances in vehicular systems, technologies and applications.
Introduction: Antimicrobial resistance (AMR) has emerged as one of the leading threats to public health. AMR possesses a multidimensional challenge that has social, economic, and environmental dimensions that encompass the food production system, influencing human and animal health. The One Health approach highlights the inextricable linkage and interdependence between the health of people, animals, agriculture, and the environment. Antibiotic use in any of these One Health areas can potentially impact the health of other areas. There is a dearth of evidence on AMR from the natural environment, such as the plant-based agriculture sector. Antibiotics, antibiotic-resistant bacteria (ARB), and related AMR genes (ARGs) are assumed to present in the natural environment and disseminate resistance to fresh produce/vegetables and thus to human health upon consumption. Therefore, this study aims to investigate the role of vegetables in the spread of AMR through an agroecosystem exploration from a One Health perspective in Ahmedabad, India.
Protocol: The present study will be executed in Ahmedabad, located in Gujarat state in the Western part of India, by adopting a mixed-method approach. First, a systematic review will be conducted to document the prevalence of ARB and ARGs on fresh produce in South Asia. Second, agriculture farmland surveys will be used to collect the general farming practices and the data on common vegetables consumed raw by the households in Ahmedabad. Third, vegetable and soil samples will be collected from the selected agriculture farms and analyzed for the presence or absence of ARB and ARGs using standard microbiological and molecular methods.
Discussion: The analysis will help to understand the spread of ARB/ARGs through the agroecosystem. This is anticipated to provide an insight into the current state of ARB/ARGs contamination of fresh produce/vegetables and will assist in identifying the relevant strategies for effectively controlling and preventing the spread of AMR.
Vection underwater
(2022)
This paper describes the development of a Pedelec controller whose performance level (PL) conforms to European standard on safety of machinery [9] and whose soft- ware is verified to conform to EPAC standard [6] by means of a software verification technique called model checking. In compliance with the standard [9] the hardware needs to implement the required properties corresponding to categories “C” and “D”. The latter is used if the breaks are not able to bring the velomobile with a broken motor controller to a full stop. Therefore the controller needs to implement a test unit, which verifies the functionality of the components and, in case of an emergency, shuts the whole hardware down to prevent injuries of the cyclist. The MTTFd can be measured through a failure graph, which is the result of a FMEA analysis, and can be used to proof that the Pedelec controller meets the regulations of the system specification. The analysis of the system in compliance with [9] usually treats the software as a black box thus ignoring its inner workings and validating its correctness by means of testing. In this paper we present a temporal logic specification according to [6], based on which the software for the Pedelec controller is implemented, and verify instead of only testing its functionality. By means of model checking [1] we proof that the software fulfills all requirements which are regulated by its specification.