1,157 research outputs found

    7e Nederlandse testdag, Eindhoven, 8 November 2001 : proceedings

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    These are the proceedings of the seventh edition of the Nederlandse Testdag (a.k.a. Dutch Testing Day), held on November 8, 2001 in Eindhoven, The Netherlands. The increase in the complexity of software and hardware systems was the predominant concern in the software design of the last decades. This increase is still going on today. and mastering this complexity is possible, only by investigating, discussing and evaluating methods and techniques for testing such systems. The Nederlandse Testdag serves as a forum in which researchers from the industry and the academia discuss and present their latest experiences and theories in the area of testing. The initiative for organising the Nederlandse Testdag is, and has always been, the result of the combined efforts of the Dutch academia and the industry. The Nederlandse Testdag is an annual event which was first held in 1995. This year's edition again consists of one invited presentation by Jens Grabowski, on ITCN-3. and six regular presentations, both from the academia and from the industry. The presentations capture a broad field of the entire testing spectrum. In the presentation by Martin Gijsen (CMG), test automation for Graphical User Interface (GUI), dedicated and embedded systems according to the TestFrame methodology is explained. Klaas Mateboer (Collis) presents the test-tool Conclusion. René de Vries (University of Twente) reports on specification testing in practice and illustrates this by means of an example. In the presentation by Loe Feijs (Eindhoven University of Technology), testing is related to game-theory. Marcel Verhoef (Chess) and Bertil Oving (NLR) present their experiences using real-time simulation, UML and VDM to obtain more reliable spacecraft avionics. Finally, Ben van Buitenen (Baan), provides an insight in service pack testing: how to efficiently test customised software components and packages. The organisation of the Nederlandse Testdag is grateful for the sponsorship it received from the Eindhoven University of Technology, the Eindhoven Embedded Systems Institute, and the financial support from Dutch Research School IPA. We are very much indebted to CMG and Telelogic's willingness to sponsor this event financially. Over the years, both companies have profiled themselves as companies investing both time and resources in advancing the current state in testing. Finally, the organisation thanks Marcella de Rooij and EIize Russell for their organisational assistance

    7e Nederlandse testdag, Eindhoven, 8 November 2001 : proceedings

    Get PDF
    These are the proceedings of the seventh edition of the Nederlandse Testdag (a.k.a. Dutch Testing Day), held on November 8, 2001 in Eindhoven, The Netherlands. The increase in the complexity of software and hardware systems was the predominant concern in the software design of the last decades. This increase is still going on today. and mastering this complexity is possible, only by investigating, discussing and evaluating methods and techniques for testing such systems. The Nederlandse Testdag serves as a forum in which researchers from the industry and the academia discuss and present their latest experiences and theories in the area of testing. The initiative for organising the Nederlandse Testdag is, and has always been, the result of the combined efforts of the Dutch academia and the industry. The Nederlandse Testdag is an annual event which was first held in 1995. This year's edition again consists of one invited presentation by Jens Grabowski, on ITCN-3. and six regular presentations, both from the academia and from the industry. The presentations capture a broad field of the entire testing spectrum. In the presentation by Martin Gijsen (CMG), test automation for Graphical User Interface (GUI), dedicated and embedded systems according to the TestFrame methodology is explained. Klaas Mateboer (Collis) presents the test-tool Conclusion. René de Vries (University of Twente) reports on specification testing in practice and illustrates this by means of an example. In the presentation by Loe Feijs (Eindhoven University of Technology), testing is related to game-theory. Marcel Verhoef (Chess) and Bertil Oving (NLR) present their experiences using real-time simulation, UML and VDM to obtain more reliable spacecraft avionics. Finally, Ben van Buitenen (Baan), provides an insight in service pack testing: how to efficiently test customised software components and packages. The organisation of the Nederlandse Testdag is grateful for the sponsorship it received from the Eindhoven University of Technology, the Eindhoven Embedded Systems Institute, and the financial support from Dutch Research School IPA. We are very much indebted to CMG and Telelogic's willingness to sponsor this event financially. Over the years, both companies have profiled themselves as companies investing both time and resources in advancing the current state in testing. Finally, the organisation thanks Marcella de Rooij and EIize Russell for their organisational assistance

    Electrical characterization of phytoplankton suspensions using impedance spectroscopy.

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    Phytoplankton are closely monitored because of their important environmental role, and the impacts they have on their local ecosystems. Some phytoplankton respond to stress by producing lipids, which can be harvested for biofuels and other chemicals. Microfluidic devices have been important in improving the portability and throughput of phytoplankton characterization methods, increasing their potential for in situ use. This study utilized a small sample of phytoplankton suspended in a stagnant medium and measured the impedance response using a lab-on-chip and impedance analyzer. The individual cell characteristics were derived from the impedance response of the group. The goal was to characterize and differentiate between algae species, as well as healthy and nitrogen deprived cells. The average cytoplasm conductivity was 14.4 mS/m for Chlamydomonas reinhardtii and Selenastrum capricornutum, and not differentiable. The species’ average membrane capacitances were differentiable, with S. capricornutum’s being 40.6 mF/m2, and nitrogen-sufficient C. reinhardtii’s being 15.5 mF/m2. Nitrogen-deficient C. reinhardtii’s average cytoplasm conductivity and membrane capacitance were 14.1 mS/m and 13.2 mF/m2

    On the Combination of Game-Theoretic Learning and Multi Model Adaptive Filters

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    This paper casts coordination of a team of robots within the framework of game theoretic learning algorithms. In particular a novel variant of fictitious play is proposed, by considering multi-model adaptive filters as a method to estimate other players’ strategies. The proposed algorithm can be used as a coordination mechanism between players when they should take decisions under uncertainty. Each player chooses an action after taking into account the actions of the other players and also the uncertainty. Uncertainty can occur either in terms of noisy observations or various types of other players. In addition, in contrast to other game-theoretic and heuristic algorithms for distributed optimisation, it is not necessary to find the optimal parameters a priori. Various parameter values can be used initially as inputs to different models. Therefore, the resulting decisions will be aggregate results of all the parameter values. Simulations are used to test the performance of the proposed methodology against other game-theoretic learning algorithms.</p

    Structural Health Monitoring (SHM) systems in aircraft: wing damage detection employing guided waves techniques

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    The doctoral thesis provides a detailed description of the implementation of methodologies and technologies based on ultrasonic guided waves for Structural Health Monitoring (SHM) on wing structural elements made of composite materials for BVID or hidden flaws detection. The developed methodologies have been first technologically integrated and applied on small scale structural elements, unstiffened and stiffened plates. Subsequently the SHM system was integrated on a full scale wing box demonstrator in order to perform the delamination detection. The implemented SHM system is capable to control a network of surface mounted piezoelectric transducers, to perform Electromechanical Impedance measurement at each transducer, to check the reliability as well as the bonding strength, and to perform an active guided wave screening

    Making decisions about screening cargo containers for nuclear threats using decision analysis and optimization

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    One of the most pressing concerns in homeland security is the illegal passing of weapons-grade nuclear material through the borders of the United States. If terrorists can gather the materials needed to construct a nuclear bomb or radiological dispersion device (RDD, i.e., dirty bomb) while inside the United States, the consequences would be devastating. Preventing plutonium, highly enriched uranium (HEU), tritium gas or other materials that can be used to construct a nuclear weapon from illegally entering the United States is an area of vital concern. There are enormous economic consequences when our nation\u27s port security system is compromised. Interdicting nuclear material being smuggled into the United States on cargo containers is an issue of vital national interest, since it is a critical aspect of protecting the United States from nuclear attacks. However, the efforts made to prevent nuclear material from entering the United States via cargo containers have been disjoint, piecemeal, and reactive, not the result of coordinated, systematic planning and analysis. Our economic well-being is intrinsically linked with the success and security of the international trade system. International trade accounts for more than thirty percent of the United States economy (Rooney, 2005). Ninety-five percent of international goods that enter the United States come through one of 361 ports, adding up to more than 11.4 million containers every year (Fritelli, 2005; Rooney, 2005; US DOT, 2007). Port security has emerged as a critically important yet vulnerable component in the homeland security system. Applying game theoretic methods to counterterrorism provides a structured technique for defenders to analyzing the way adversaries will interact under different circumstances and scenarios. This way of thinking is somewhat counterintuitive, but is an extremely useful tool in analyzing potential strategies for defenders. Decision analysis can handle very large and complex problems by integrating multiple perspectives and providing a structured process in evaluating preferences and values from the individuals involved. The process can still ensure that the decision still focuses on achieving the fundamental objectives. In the decision analysis process value tradeoffs are evaluated to review alternatives and attitudes to risk can be quantified to help the decision maker understand what aspects of the problem are not under their control. Most of all decision analysis provides insight that may not have been captured or fully understood if decision analysis was not incorporated into the decision making process. All of these factors make decision analysis essentially to making an informed decision. Game theory and decision analysis both play important roles in counterterrorism efforts. However, they both have their weaknesses. Decision analysis techniques such as probabilistic risk analysis can provide incorrect assessments of risk when modeling intelligent adversaries as uncertain hazards. Game theory analysis also has limitations. For example when analyzing a terrorist or terrorist group using game theory we can only take into consideration one aspect of the problem to optimize at a time. Meaning the analysis is either analyzing the problem from the defenders perspective or from the attacker’s perspective. Parnell et al. (2009) was able to develop a model that simultaneously maximizes the effects of the terrorist and minimizes the consequences for the defender. The question this thesis aims to answer is whether investing in new detector technology for screening cargo containers is a worthwhile investment for protecting our country from a terrorist attack. This thesis introduces an intelligent adversary risk analysis model for determining whether to use new radiological screening technologies at our nation’s ports. This technique provides a more realistic risk assessment of the true situation being modeled and determines whether it is cost effective for our country to invest in new cargo container screening technology. The optimal decision determined by our model is for the United States to invest in a new detector, and for the terrorists to choose agent cobalt-60, shown in Figure 18. This is mainly due to the prominence of false alarms and the high costs associated with screening all of these false alarms, and we assume for every cargo container that sounds an alarm, that container is physically inspected. With the new detector technology the prominence of false alarms decreases and the true alarm rate increases, the cost savings associated with this change in the new technology outweighs the cost of technical success or failure. Since the United States is attempting to minimize their expected cost per container, the optimal choice is to invest in the new detector. Our intelligent adversary risk analysis model can simultaneously determine the best decision for the United States, who is trying to minimize the expected cost, and the terrorist, who is trying to maximize the expected cost to the United States. Simultaneously modeling the decisions of the defender and attacker provides a more accurate picture of reality and could provide important insights to the real situation that may have been missed with other techniques. The model is extremely sensitive to certain inputs and parameters, even though the values are in line with what is available in the literature, it is important to understand the sensitivities. Two inputs that were found to be particularly important are the expected cost for physically inspecting a cargo container, and the cost of implementing the technology needed for the new screening device. Using this model the decision maker can construct more accurate judgments based on the true situation. This increase in accuracy could save lives with the decisions being made. The model can also help the decision maker understand the interdependencies of the model and visually see how his resource allocations affect the optimal decisions of the defender and the attacker
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