12 research outputs found

    Design and evaluation of a framework for cooperative and adaptive QoS control of DSRC network for road safety applications

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    Dedicated short-range communications (DSRC) are a promising vehicle communication technique for collaborative road safety applications (CSA). However, road safety applications require highly reliable and timely wireless communications, which present big challenges to DSRC based vehicle networks on effective and robust quality of services (QoS) provisioning due to the random channel access method applied in the DSRC technique. In this paper we examine the QoS control problem for CSA in the DSRC based vehicle networks and presented an overview of the research work towards the QoS control problem. After an analysis of the system application requirements and the DSRC vehicle network features, we propose a framework for cooperative and adaptive QoS control, which is believed to be a key for the success of DSRC on supporting effective collaborative road safety applications. A core design in the proposed QoS control framework is that network feedback and cross-layer design are employed to collaboratively achieve targeted QoS. A design example of cooperative and adaptive rate control scheme is implemented and evaluated, with objective of illustrating the key ideas in the framework. Simulation results demonstrate the effectiveness of proposed rate control schemes in providing highly available and reliable channel for emergency safety messages

    Advances in Vehicular Ad-hoc Networks (VANETs): challenges and road-map for future development

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    Recent advances in wireless communication technologies and auto-mobile industry have triggered a significant research interest in the field of vehicular ad-hoc networks (VANETs) over the past few years. A vehicular network consists of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications supported by wireless access technologies such as IEEE 802.11p. This innovation in wireless communication has been envisaged to improve road safety and motor traffic efficiency in near future through the development of intelligent transportation system (ITS). Hence, governments, auto-mobile industries and academia are heavily partnering through several ongoing research projects to establish standards for VANETs. The typical set of VANET application areas, such as vehicle collision warning and traffic information dissemination have made VANET an interesting field of mobile wireless communication. This paper provides an overview on current research state, challenges, potentials of VANETs as well as the ways forward to achieving the long awaited ITS

    Effectiveness of Theory-Based Health Information Technology Interventions on Coronary Artery Disease Self-Management Behavior: A Clinical Randomized Waitlist-Controlled Trial

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    [[abstract]]Purpose: Secondary prevention of coronary artery disease, self-management behavior, and blood pressure control are important to cardiovascular event prevention and promotion of quality of life (QOL), but they are underutilized. The purpose of this study was to investigate the effects of a self-efficacy theoryā€“based health information technology intervention implemented through blood control and patient self-management. Design: A clinical randomized waitlist-controlled trial. Methods: The study was conducted at a medical center in Taipei, Taiwan. A total of 60 subjects were randomly assigned to either the immediate intervention (experimental) group or the waitlist control group. The primary endpoint was systolic blood pressure at 3 months; secondary end points included self-management behavior and QOL. Treatment for the immediate intervention group lasted 3 months, while the waitlist control group received routine care for the first 3 months, at which point they crossed over to the intervention arm and received the same intervention as the experimental group for another 3 months. Both groups were evaluated by questionnaires and physiological measurements at both 3 and 6 months postadmission. The results were analyzed using generalized estimating equations. Results: Systolic blood pressure significantly improved for the intervention group participants at 3 months, when there was also significant improvement in self-management behavior and QOL. There was no significant or appreciable effect of time spent in the waitlist condition, with treatments in the two conditions being similarly effective. Conclusion: The use of a theory-based health information technology treatment compared with usual care resulted in a significant improvement in systolic blood pressure, self-management behavior, and QOL in patients with coronary artery disease. Clinical Relevance: This treatment would be a useful strategy for clinical care of cardiovascular disease patients, improving their disease self-management. It also may help guide further digital health care strategies during the COVID-19 pandemic.[[notice]]č£œę­£å®Œ

    Sustainable Synthesis of Pseudopeptides via Isocyanide-Based Multicomponent Reactions in Water

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    The impressive success in the synthesis of novel products via sustainable and green methods is a crucial purpose in organic synthesis. Water as a "green solvent"plays a vital role in accelerating some organic reactions, displaying unique reactivity and selectivity from conventional organic solvents. The isocyanide-based multicomponent reactions (I-MCRs) as sustainable and versatile reactions have received significant consideration in the synthesis of pseudopeptidic frames, especially in drug discovery. This is because of the unique nature of isocyanides that play as a special active reactant. I-MCRs in water as a solvent and reagent for the synthesis of pseudopeptidic compounds have become an interesting research direction, enabling simultaneous growth of both I-MCRs and green solvents toward ideal organic synthesis. The reaction rate of I-MCRs was accelerated in water as a solvent due to the lower activation volumes and condensation of several reactants into a single reactive intermediate and product. Furthermore, I-MCRs executed possibly in water are mild, easily controlled, and environmentally friendly, which conform well to "Green Chemistry"principles. On the other hand, these powerful organic syntheses in water and aqueous media are perpetuated by acceleration and reduction in the number of workups, purification, and extraction steps. The main subject of this review is I-MCRs that are performed in the water toward the sustainable synthesis of pseudopeptide structures. It deserves to be pointed out that whereas significant progress has been recently made on the MCRs in water and aqueous media for organic transformations, there is no exclusive account to focus on and publish about the eco-friendly I-MCRs for pseudopeptides. Nevertheless, we hope this themed assemblage will be attractive and useful for organic and pharmaceutical chemists and encourage more reaction development in this fascinating engaging field. Ā© 2022 American Chemical Society
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