基于PC的单线测温网络的设计与实现

利用单线数字温度传感器和单线网络结构,可以建立分布式的单线多区域的温度测量网络。每个单线器件通过一根线连接在一起,并且有唯一的64位地址,通过它识别不同的器件。文章介绍了单线测温网络的设计和实施。

单线铁路网络列车运行智能调度仿真研究

铁路调度指挥旨在保障在线列车安全有序运行,而实现调度指挥智能化是铁路运输现代化的重要标志。单线铁路网络由于两车站间仅一条线路供双方向列车运行,其调度指挥智能化方法的实现需解决双方向列车在其运行过程中的智能冲突疏解及线路死锁防护机制等难点问题。基于多Agent分析单线铁路网络中列车运行冲突判断条件、死锁判断条件,并提出列车运行冲突疏解及死锁防护机制。运用黑板结构的多Agent通信机制,建立单线铁路网络列车运行智能调度仿真模型。利用Anylogic将该仿真模型运用于西南地区某实际单线铁路网络,仿真结果表明所提出仿真模型能够保证单线铁路网络列车运行调度决策的有效性及合理性,是列车运行智能调度研究的有效手段。

Distributed Low-Complexity Channel Assignment for Opportunistic Routing

Opportunistic Routing (OR) involves multiple forwarding candidates to relay packets by taking advantage of the broadcast nature and multi-user diversity of a wireless medium. Compared with Traditional Routing (TR), OR is more suitable in the case of an unreliable wireless link and can evidently improve the end-to-end throughput of Wireless Mesh Networks (WMNs). In this paper, we focus on OR in Multi-Radio Multi-Channel WMNs (MRMC-WMNs). This problem has not been well examined and is considerably more challenging than the OR in single-radio wireless networks considered in the existing literature. First, we validate the advantage of OR in MRMC-WMNs. Second, we propose Low-complexity Channel Assignment for Opportunistic Routing (LcCAOR), which assigns channels to flows according to the interference state of every node. Third, we implement the LcCOAR in a fully distributed manner. The simulation result shows that compared with OR in Single-Radio Single-Channel WMNs (SRSC-WMNs), the proposed OR can significantly enhance the throughput to 87.11% and 100.3% in grid and tree WMNs, respectively.

Dynamic Cell Range Expansion-based Interference Coordination Scheme in Next Generation Wireless Networks

Deploying Picocell Base Station(PBS) throughout a Macrocell is a promising solution for capacity improvement in the next generation wireless networks.However,the strong received power from Macrocell Base Station(MBS) makes the areas of Picocell narrow and limits the gain of cell splitting.In this paper,we firstly propose a Dynamic Cell Range Expansion(DCRE) strategy.By expanding the coverage of the cell,we aim to balance the network load between MBS and PBS.Then,we present a cooperative Resource block and Power Allocation Scheme(coRPAS)based on DCRE.The objective of coRPAS is to decrease interference caused by MBS and Macrocell User Equipments,by which we can expand regions of Picocell User Equipments.Simulation results demonstrate the superiority of our method through comparing with other existing methods.

An Integrated Tool for Power/Ground Network Design, Optimization,and Verification for Cell Based VLSIs

A CAD tool based on a group of efficient algorithms to verify,design,and optimize power/ground networks for standard cell model is presented.Nonlinear programming techniques,branch and bound algorithms and incomplete Cholesky decomposition conjugate gradient method (ICCG) are the three main parts of our work.Users can choose nonlinear programming method or branch and bound algorithm to satisfy their different requirements of precision and speed.The experimental results prove that the algorithms can run very fast with lower wiring resources consumption.As a result,the CAD tool based on these algorithms is able to cope with large-scale circuits.

Ba4M（CO3）2（BO3）2（M=Ba, Sr）: two borate-carbonates synthesized by open high temperature solution method

Two borate-carbonates Ba4M(CO3)2(BO3)2(M =Ba, Sr) have been successfully synthesized in the open air representing the first examples of borate-carbnate complex.Their structures were determined by single crystal X-ray diffraction and they both crystallize in same space group, Pnma.Their structures feature a Ba/Sr-based three dimensional framework composed of the BaO8 polyhedra(the SrO8 polyhedra), isolated BO3 and CO3 triangles. Detailed structure analysis shows that the intergrowth of [Ba3(BO3)2]/[Ba2Sr(BO3)2] and [BaCO3] layers favors the formation of these two borate-carbonates. In addition, their syntheses, spectroscopic properties and thermal behaviors were investigated.

An engineering approach to improve the accuracy of one-step simulation for vehicle forming-to-crashworthiness integrated evaluation

To improve the accuracy of the vehicle crashworthiness simulation, it is necessary as well as important to integrate the valid forming effects of key parts. It has been agreed by many that one-step simulation results should be used only as a qualitative trend of the part but not as an engineering result for further structural analysis, especially for a relatively complex part. The study shows that it is inaccurate to analyze the forming effects with one-step simulation based on the geometry of the final part through comparison with the incremental simulation and verification with the actual part, whether in thickness or in plastic strain. However, incremental simulation is very time consuming and infeasible in the early stage of vehicle design due to lack- ing of forming tools and process parameters. An engineering approach is proposed to meet the requirement of accuracy as well as the time efficiency, where one-step simulation is conducted based on the geometry of the transformed part instead of the fi- nN part. The geometry of the transformed part is generated by simple die design engineering and proves to offer much more accuracy than the one-step simulation based on the final part geometry.

Physical layer security of underlay cognitive radio using maximal ratio combining

We investigate the secrecy outage performance of maximal ratio combining(MRC) in cognitive radio networks over Rayleigh fading channels. In a single-input multiple-output wiretap system, we consider a secondary user(SU-TX) that transmits confidential messages to another secondary user(SU-RX) equipped with M(M ≥ 1)antennas where the MRC technique is adopted to improve its received signal-to-noise ratio. Meanwhile, an eavesdropper equipped with N(N ≥ 1) antennas adopts the MRC scheme to overhear the information between SU-TX and SU-RX. SU-TX adopts the underlay strategy to guarantee the service quality of the primary user without spectrum sensing. We derive the closed-form expressions for an exact and asymptotic secrecy outage probability.