205 research outputs found

    Prototype system development for wireless vehicle speed monitoring

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    Vehicle speed monitoring and management of the associated data in an intelligent and efficient way is an important issue in modern transportation system in order to reduce road accidents. The aim of this work is to develop an automatic wireless system for monitoring vehicle speed on the road, identify a speeding vehicle and imposing penalty for the speeding offenders. In this work, a prototype system has been developed in a laboratory environment to generate random speed data using a mechanical wheel, measure the speed data with a Shimmer wireless sensor and transfer the data wirelessly to a client computer for further analysis. Software has been developed using a Java based socket programming technique to monitor the vehicle speed in a server computer and to send the data associated with a speeding vehicle to a remotely placed client computer. The graphical user interface (GUI) can visually display the speed of a vehicle at any particular time. The functionality of the software has been tested by simulating different traffic scenarios with low and high speed limits (40 and 60 km/hr respectively). To do that a high or low speed limit can be set in the GUI. The mechanical wheel is run at different speeds and the GUI continuously displays the speed. If the vehicle speed is higher than the set speed limit for the road, the system automatically detects it and generates a report with the time of speeding, vehicle number, vehicle speed etc. to be saved in the client computer in order to take further necessary actions for the speeding offender

    Developmental Parameters of a Southern Mountain Pine Beetle (Coleoptera: Curculionidae) Population Reveal Potential Source of Latitudinal Differences in Generation Time

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    Mountain pine beetle (Dendroctonus ponderosae, Hopkins) is a major disturbance agent in pine ecosystems of western North America. Adaptation to local climates has resulted in primarily univoltine generation time across a thermally diverse latitudinal gradient. We hypothesized that voltinism patterns have been shaped by selection for slower developmental rates in southern populations inhabiting warmer climates. To investigate traits responsible for latitudinal differences we measured lifestage-specific development of southern mountain pine beetle eggs, larvae and pupae across a range of temperatures. Developmental rate curves were fit using maximum posterior likelihood estimation with a Bayesian prior to improve fit stability. When compared to previously published data for a northern population (RégniÚre et al. 2012), optimal development of southern individuals occurred at higher temperatures, with higher development thresholds, as compared with northern individuals. Observed developmental rates of the southern and northern populations were similar across studied lifestages at 20 °C, and southern lifestages were generally faster at temperature extremes (10, 27 °C). At 25 °C southern fourth instars were significantly slower than northern fourth instars. Our results suggest that evolved traits in the fourth instar and remaining unstudied lifestage, teneral (i.e., pre-emergent) adult, likely influence latitudinal differences in mountain pine beetle generation time

    A Multi-Agent Based Vehicles Re-routing System for Unexpected Traffic Congestion Avoidance

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    As urbanization has been spreading across the world for decades, the traffic congestion problem becomes increasingly serious in most of the major cities. Among the root causes of urban traffic congestion, en route events are the main source of the sudden increase of the road traffic load, especially during peak hours. The current solutions, such as on-board navigation systems for individual vehicles, can only provide optimal routes using current traffic data without considering any traffic changes in the future. Those solutions are thus unable to provide a better alternative route quickly enough if an unexpected congestion occurs. Moreover, using the same alternative routes may lead to new bottlenecks that cannot be avoided. Thus a global traffic load balance cannot be achieved. To deal with these problems, we propose a Multi Agent System (MAS) that can achieve a trade-off between the individual and global benefits by giving the vehicles optimal turn suggestions to bypass a blocked road ahead. The simulation results show that our strategy achieves a substantial gain in average trip time reduction under realistic scenarios. Moreover, the negative impact of selfish re-routing is investigated to show the importance of altruistic re-routing applied in our strategy

    An Adaptive and VANETs-based Next Road Re-routing System for Unexpected Urban Traffic Congestion Avoidance

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    Unexpected road traffic congestion caused by en-route events, such as car crashes, road works, unplanned parades etc., is a real challenge in today's urban road networks as it considerably increases the drivers' travel time and decreases travel time reliability. To face this challenge, this paper extends our previous work named Next Road Rerouting (NRR) by designing a novel vehicle rerouting strategy that can adapt itself to the sudden change of urban road traffic conditions. This is achieved through a smart calibration of the algorithmic and operational parameters of NRR without any intervention from traffic managers. Specifically, a coefficient of variation based method is used to assign weight values to three factors in the routing cost function of NRR, and the k-means algorithm is applied periodically to choose the number of NRR enabled agents needed. This adaptive-NRR (a-NRR) strategy is supported by vehicular ad-hoc networks (VANETs) technology as this latter can provide rich traffic information at much higher update frequency and much larger coverage than induction loops used in the previously proposed static NRR. Simulation results show that in the city center area of TAPASCologne scenario, compared to the existing vehicle navigation system (VNS) and static NRR, our adaptive-NRR can achieve considerable gain in terms of trip time reduction and travel time reliability improvement

    Developing intelligent software interface for wireless monitoring of vehicle speed and management of associated data

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    The aim of this work is to develop an intelligent wireless system for monitoring vehicle speed, identify speeding vehicles and imposing penalty for the speeding offenders. A prototype system has been developed in a laboratory environment to generate random speed data using a mechanical wheel (acts as a vehicle), measure the speed data with a Shimmer wireless sensor and transfer the data wirelessly to a server computer for further analysis. Software interface has been developed using Java based socket-programming to monitor the vehicle speed in a server computer and to send the data associated with a speeding vehicle to a remotely placed client computer. The functionality of the software has been tested by experimenting different traffic scenarios. If the vehicle speed is higher than the set speed limit for the road, the system automatically detects it and generates a report with the time of speeding, vehicle number, vehicle speed, etc. The report is saved in a central database (client computer) in order to take further necessary actions for the speeding offender. The experimental evaluation results show that the system can measure and monitor the vehicle speeds wirelessly and manage the speeding data automatically

    Interrupt Timed Automata: verification and expressiveness

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    We introduce the class of Interrupt Timed Automata (ITA), a subclass of hybrid automata well suited to the description of timed multi-task systems with interruptions in a single processor environment. While the reachability problem is undecidable for hybrid automata we show that it is decidable for ITA. More precisely we prove that the untimed language of an ITA is regular, by building a finite automaton as a generalized class graph. We then establish that the reachability problem for ITA is in NEXPTIME and in PTIME when the number of clocks is fixed. To prove the first result, we define a subclass ITA- of ITA, and show that (1) any ITA can be reduced to a language-equivalent automaton in ITA- and (2) the reachability problem in this subclass is in NEXPTIME (without any class graph). In the next step, we investigate the verification of real time properties over ITA. We prove that model checking SCL, a fragment of a timed linear time logic, is undecidable. On the other hand, we give model checking procedures for two fragments of timed branching time logic. We also compare the expressive power of classical timed automata and ITA and prove that the corresponding families of accepted languages are incomparable. The result also holds for languages accepted by controlled real-time automata (CRTA), that extend timed automata. We finally combine ITA with CRTA, in a model which encompasses both classes and show that the reachability problem is still decidable. Additionally we show that the languages of ITA are neither closed under complementation nor under intersection

    Developing evaluation tools for assessing the educational potential of apps for preschool children in the UK

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    Selecting high quality apps can be challenging for caregivers and educators. We here develop tools evaluating educational potential of apps for preschool children. In Study 1, we developed two complementary evaluation tools tailored to different audiences. We grounded them in developmental theory and linked them to research on children’s experience with digital media. In Study 2 we applied these tools to a wide sample of apps in order to illustrate their use and to address the role of cost in quality of educational apps. There are concerns that a social disadvantage may lead to a digital disadvantage, an “app gap”. We thus applied our tools to the most popular free (N=19) and paid (N=24) apps targeting preschoolers. We found that the “app gap” associated with cost is only related to some aesthetic features of apps rather than any observable educational advantage proffered by paid apps. Our study adds a novel contribution to the research on children’s apps by developing tools to be used across a wide range of audiences, providing the first description of the quantity of app design features during app use and evaluating the educational potential of free and paid apps

    Interventions aimed at improving the nursing work environment: a systematic review

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    <p>Abstract</p> <p>Background</p> <p>Nursing work environments (NWEs) in Canada and other Western countries have increasingly received attention following years of restructuring and reported high workloads, high absenteeism, and shortages of nursing staff. Despite numerous efforts to improve NWEs, little is known about the effectiveness of interventions to improve NWEs. The aim of this study was to review systematically the scientific literature on implemented interventions aimed at improving the NWE and their effectiveness.</p> <p>Methods</p> <p>An online search of the databases CINAHL, Medline, Scopus, ABI, Academic Search Complete, HEALTHstar, ERIC, Psychinfo, and Embase, and a manual search of Emerald and Longwoods was conducted. (Quasi-) experimental studies with pre/post measures of interventions aimed at improving the NWE, study populations of nurses, and quantitative outcome measures of the nursing work environment were required for inclusion. Each study was assessed for methodological strength using a quality assessment and validity tool for intervention studies. A taxonomy of NWE characteristics was developed that would allow us to identify on which part of the NWE an intervention targeted for improvement, after which the effects of the interventions were examined.</p> <p>Results</p> <p>Over 9,000 titles and abstracts were screened. Eleven controlled intervention studies met the inclusion criteria, of which eight used a quasi-experimental design and three an experimental design. In total, nine different interventions were reported in the included studies. The most effective interventions at improving the NWE were: primary nursing (two studies), the educational toolbox (one study), the individualized care and clinical supervision (one study), and the violence prevention intervention (one study).</p> <p>Conclusions</p> <p>Little is known about the effectiveness of interventions aimed at improving the NWE, and published studies on this topic show weaknesses in their design. To advance the field, we recommend that investigators use controlled studies with pre/post measures to evaluate interventions that are aimed at improving the NWE. Thereby, more evidence-based knowledge about the implementation of interventions will become available for healthcare leaders to use in rebuilding nursing work environments.</p

    High-temperature batteries for geothermal and oil/gas borehole applications

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    A literature survey and technical evaluation was carried out of past and present battery technologies with the goal of identifying appropriate candidates for use in geothermal borehole and, to a lesser extent, oil/gas boreholes. The various constraints that are posed by such an environment are discussed. The promise as well as the limitations of various candidate technologies are presented. Data for limited testing of a number of candidate systems are presented and the areas for additional future work are detailed. The use of low-temperature molten salts shows the most promise for such applications and includes those that are liquid at room temperature. The greatest challenges are to develop an appropriate electrochemical couple that is kinetically stable with the most promising electrolytes--both organic as well as inorganic--over the wide operating window that spans both borehole environments

    Being user-oriented: convergences, divergences, and the potentials for systematic dialogue between disciplines and between researchers, designers, and providers

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    The challenge this panel addresses is drawn from intersecting literature reviews and critical commentaries focusing on: 1) user studies in multiple fields; and 2) the difficulties of bringing different disciplines and perspectives to bear on user‐oriented research, design, and practice. 1 The challenge is that while we have made some progress in collaborative work, we have some distance to go to become user‐oriented in inter‐disciplinary and inter‐perspective ways. The varieties of our approaches and solutions are, as some observers suggest, an increasing cacophony. One major difficulty is that most discussions are solution‐oriented, offering arguments of this sort ‐‐ if only we addressed users in this way
 Each solution becomes yet another addition to the cacophony. This panel implements a central approach documented for its utility by communication researchers and long used by communication mediators and negotiators ‐‐ that of focusing not on communication but rather on meta‐communication: communicating about communication. The intent in the context of this panel is to help us refocus attention from too frequent polarizations between alternative solutions to the possibility of coming to understand what is behind the alternatives and where they point to experientially‐based convergences and divergences, both of which might potentially contribute to synergies. The background project for this panel comes from a series of in‐depth interviews with expert researchers, designers, and providers in three field groupings ‐‐ library and information science; human computer interaction/information technology; and communication and media studies. One set of interviews involved 5‐hour focus groups with directors of academic and public libraries serving 44 colleges and universities in central Ohio; the second involved one‐on‐one interviews averaging 50 minutes with 81 nationally‐internationally known experts in the 3 fields, 25‐27 interviews per field. Using Dervin\u27s Sense‐Making Methodological approach to interviewing, the expert interviews of both kinds asked each interviewee: what he/she considered to be the big unanswered questions about users and what explained why the questions have not been answered; and, what he/she saw as hindering versus helping in attempts to communicate about users across disciplinary and perspective gaps. 2 The panel consists of six teams, two from each field. Prior to the panel presentation at ASIST, each team will have read the set of interviews and completed impressionistic essays of what patterns and themes they saw as emerging. At this stage, team members will purposively not homogenize their differences and most will write solo‐authored essays that will be placed on a web‐site accessible to ASIST members prior to the November meeting. In addition, at least one systematic analysis will be completed and available online. 3 At the ASIST panel, each team\u27s leader will present a brief and intentionally provocative impressionist account of what his/her team came to understand about our struggles communicating across fields and perspectives about users. Again, each team will purposively not homogenize its own differences in viewpoints, but rather highlight them as fodder for discussion. A major purpose will be to invite audience members to join the panel in discussion. At least 20 minutes will be left open for this purpose
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