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Formal Reliability Analysis of Wireless Sensor Network Data Transport Protocols using HOL
No full textAbstract-In recent times, Wireless Sensor Networks (WSNs) have shown a great potential for monitoring physical or environmental conditions in a variety of safety and financialcritical applications, ranging from medicine to transportation and surveillance. Given the extreme conditions of most of the WSN environments, it is very important to make WSN communication resilient to network failures. Various data transport protocols have been proposed in the literature to serve this purpose. The reliability of these WSN data transport protocols is usually assessed by using Reliability Block Diagrams (RBDs). Traditionally, RBD-based reliability analyses of WSN data transport protocols is done using paper-and-pencil proofs or computer simulations, which cannot ascertain absolute correctness due to their inherent incompleteness. As a complementary approach, we propose to use the higher-order-logic theorem prover HOL to conduct the RBD-based reliability analysis of WSN data transport protocols. In particular, the paper provides a higher-order-logic formalization of series, parallel and parallel-series RBDs. These RBDs are then used to do the formal reliability analysis of the end-to-end (e2e) data transport mechanism, and the Event to Sink Reliable Transport (ESRT) and Reliable Multi-Segment Transport (RMST) data transport protocols
A Theory of Commerce: Competitive Search Under Private Information
No full textAbstract We extend the concept of competitive search to an environment where, as is often common, sellers cannot observe the willingness to pay of their clients. This theoretical contribution is applied to model retail trade. We Þnd that in equilibrium the ratio of buyers over sellers exceeds that of the Þrst best allocation. Furthermore, upon meeting a seller, buyers purchase lower quantities than in the Þrst best. Nevertheless, a planner who faces the same informational constraints as the market and whose only policy instrument is to regulate market prices cannot improve upon the equilibrium allocation when the production technology is linear. In contrast, if the planner can use lump-sum taxes to subsidize sales, the Þrst best allocation can be attained by introducing a linear sales subsidy. The model we construct is highly tractable, and when inserted in a Neoclassical growth framework it is sufficiently rich to be taken to the data for estimation. The search parameters can be identiÞed with data on commercial margins and on the households' allocation of time
A Method of Construction of The Maximal Lattice of Infinite Cyclic Groups
No full textABSTRACT In this paper we give a construction of the maximal lattice of infinite cyclic groups
ANALYSIS OF COUPLED NEUTRONIC-THERMOHYDRAULIC INSTABILITIES IN SUPERCRITICAL WATER-COOLED REACTOR BY LUMPED PARAMETER MODELING
No full textABSTRACT The possibility of instabilities in future nuclear reactors cooled by supercritical water is a matter of concern due to sharp changes in thermodynamic properties of coolant within the core. In the present work, a lumped parameter dynamic model of supercritical water-cooled reactor has been developed for analysis of coupled neutronic-thermohydraulic instabilities. The coolant channel is divided into two nodes with a moving boundary between them. The heater wall dynamics is described by a lumped parameter energy balance. Point neutron kinetics with one group of delayed neutrons has been used to model the power dynamics. Simple non-dimensional equations of state have been obtained for evaluating thermodynamic properties. Stability analysis has been done for various values of parameters such as the reactor power, coolant mass flow rate and inlet temperature. Stability maps have been plotted in the parameter planes. Dynamic simulations have been performed in the time domain to study the nature of operating transients. The stability analysis with neutronics is found to be more conservative. Transient simulations without neutronics indicate a supercritical Hopf bifurcation and the existence of a stable limit cycles in the unstable region. However, simulations with coupled neutronics indicate a subcritical Hopf bifurcation and the existence of unstable limit cycles in the stable region. Therefore, the analysis with neutronics is more conservative and shows that the system can be unstable for large perturbations, even if it is stable for small perturbations
No full textAbstract Use and the value thereof are implicit in the design discourse and therefore rarely explicitly spoken of, although they are at the core of design practice. With the recent turn to a service dominant logic perspective, the service marketing discourse opens up for understanding value as value-in-use and value-in-context. This paper empirically explores and describes ways in which professional designers themselves express "value-in-use". The findings suggest that professional designers do not focus explicitly on value as a standalone concept, but conceptualize value-in-use through contextualization and an extensive use of emotions
Climate Change and Psychological Adaptation: A Behavioral Environmental Economics Approach **
No full textAbstract Economic models of climate policy (or policies to combat other environmental problems) typically neglect psychological adaptation to changing life circumstances. People may adapt or become more sensitive, to different degrees, to a deteriorated environment. The present paper addresses these issues in a simple model of tax policy to combat climate change and elaborates on the consequences for optimal climate policies, and argues from a normative point of view that psychological adaptation needs to be taken into account by a pure welfarist government, which aims at internalizing an intertemporal externality
4 Design, Manufacturing and Testing of Polymer Composite Multi-Leaf Spring for Light Passenger Automobiles -A Review
No full text15+ MILLION TOP 1% MOST CITED SCIENTIST 12.2% AUTHORS AND EDITORS FROM TOP 500 UNIVERSITIES 4 Design, Manufacturing and Testing of Polymer Composite Multi-Leaf Spring for Light Passenger Automobiles -A Review
No full textDust grains as a Diagnostic Tool for RF-Discharge Plasma
No full textAbstract. Dust particles can be a useful plasma diagnostic tool. Sufficiently dust particles can be used as test grains for the visualization of the plasma potential distribution; larger dust particles can be used as specific probes to determine electron temperature. Here we report on diagnostic measurements carried out in a capacitively coupled planar rf discharge. The location of the sheath edge has been determined using test dust grains. Our diagnostic technique is based on measuring the equilibrium position of fine grains levitated above the powered electrode in an rf-discharge. Estimates show that for grains with radii less than 500 mm the grain equilibrium position and sheath edge location differ by less than 5 percent, and this difference continues to decrease with decreasing investigate grain radius. We use this technique to diagnose the sheath in an argon plasma which was generated at pressures in the range 20-100 mTorr by applying a 15 MHz signal to the power electrode. The shape of the potential well above the confining electrode was also visualized using even smaller dust grains that were generated in the discharge. The well shape was found to depend strongly on the confining potential