Simulation Framework for Cooperative Adaptive Cruise Control with Empirical DSRC Module

Wireless communication plays a vital role in the promising performance of connected and automated vehicle (CAV) technology. This paper proposes a Vissim-based microscopic traffic simulation framework with an analytical dedicated short-range communication (DSRC) module for packet reception. Being derived from ns-2, a packet-level network simulator, the DSRC probability module takes into account the imperfect wireless communication that occurs in real-world deployment. Four managed lane deployment strategies are evaluated using the proposed framework. While the average packet reception rate is above 93\% among all tested scenarios, the results reveal that the reliability of the vehicle-to-vehicle (V2V) communication can be influenced by the deployment strategies. Additionally, the proposed framework exhibits desirable scalability for traffic simulation and it is able to evaluate transportation-network-level deployment strategies in the near future for CAV technologies.Comment: 6 pages, 6 figure, 44th Annual Conference of the IEEE Industrial Electronics Societ

A novel approach to detect hot-spots in large-scale multivariate data

Background: Progressive advances in the measurement of complex multifactorial components of biological processes involving both spatial and temporal domains have made it difficult to identify the variables (genes, proteins, neurons etc.) significantly changed activities in response to a stimulus within large data sets using conventional statistical approaches. The set of all changed variables is termed hot-spots. The detection of such hot spots is considered to be an NP hard problem, but by first establishing its theoretical foundation we have been able to develop an algorithm that provides a solution. Results: Our results show that a first-order phase transition is observable whose critical point separates the hot-spot set from the remaining variables. Its application is also found to be more successful than existing approaches in identifying statistically significant hot-spots both with simulated data sets and in real large-scale multivariate data sets from gene arrays, electrophysiological recording and functional magnetic resonance imaging experiments. Conclusion: In summary, this new statistical algorithm should provide a powerful new analytical tool to extract the maximum information from complex biological multivariate data

Characterization of Ultra Wideband Multiple Access Performance Using Time Hopped-Biorthogonal Pulse Position Modulation

The FCC\u27s release of its UWB First Report and Order in April 2002 spawned renewed interest in impulse signaling research. This work combines Time Hopped (TH) multiple access coding with 4-ary UWB Biorthogonal Pulse Position Modulation (TH-BPPM). Multiple access performance is evaluated in a multipath environment for both synchronous and asynchronous networks. Fast time hopping is implemented by replicating and hopping each TH-BPPM symbol NH times. Bit error expressions are derived for biorthogonal TH-BPPM signaling and results compared with previous orthogonal TH-PPM work. Without fast time hopping (NH = 1), the biorthogonal TH-BPPM technique provided gains equivalent to Gray-coded QPSK; improved BER at a given Eb/No and an effective doubling of the data rate. A synchronized network containing up to NT = 15 transmitters yields an average BER improvement (relative to an asynchronous network) of approximately -6.30 dB with orthogonal TH-PPM and approximately 5.9 dB with biorthogonal TH-BPPM. Simulation results indicate that doubling the number of multipath replications (NMP) reduces BER by approximately 3.6 dB. Network performance degrades as NT and NMP increase and synchronized network advantages apparent in the NMP = 0 case diminish with multipath interference present. With fast time hopping (NH \u3e 1) improves BER performance whenever NMP \u3c NH while reducing effective data rate by 1/NH. Compared to the NH = 1 synchronized network, TH-BPPM modulation using NH = 10 provides approximately 5.9 dB improvement at NMP = 0 and approximately 3.6 dB improvement at NMP = 5. At NMP = 10, the BER for the hopped and NH = 1 cases are not statistically different; with NH = 10 hops, BER improvement varies from approximately 0.57 to 0.14 dB (minimal variation between synchronous and asynchronous network performance)

The Optimality of the US and Euro Area Taylor Rule

The purpose of this paper is to examine the optimality of the monetary authorities reaction function in the two-area medium size model MARCOS (US and euro areas). The parameters and the horizons of output gap and inflation expectations of the Taylor rule are computed in order to minimise a loss function of the monetary authorities. However, investigating the optimality of the Taylor rule in the context of a large scale macroeconomic model raises several difficulties: the model is non-linear and all the state variables potentially enter the optimal monetary policy rule. Furthermore, the optimality of the Taylor rule is assessed by the minimisation of the loss function under the constraint of a large forward-looking model. To overcome these problems, Black, Macklem and Rose [1998] propose a stochastic simulation based method which has been applied to single-country macroeconomic models. To study the optimality of the Taylor rule in the case of a two-area model, we suppose that the economy is stochastically hit by numerous shocks (supply, demand, monetary, exchange rate and world demand) in each area and simulate MARCOS stochastically.Monetary Policy, Computational Techniques, International Policy Transmission

Trade and Synchronization in a Multi-Country Economy

Substantial evidence suggests that countries or regions with stronger trade linkages tend to have business cycles that are more synchronized. The standard international business cycle framework cannot replicate this nding. In this paper, we study a multi-country model of international trade with vertical trade linkages, imperfect competition, and variable markups. We embed it in a real business cycle framework by including aggregate technology shocks and allowing for a variable labor supply. A carefully calibrated version of the theoretical economy that ts the model to data on the bilateral trade volume between 210 distinct country-pairs explains between 20 and 41 percent of the relation between trade intensity and business cycle synchronization. We provide empirical evidence supporting the model's predictions for the association between trade costs and business cycle synchronization, and exchange rate volatility and business cycle synchronization.Trade Integration, Business Cycle Synchronization