ECAP细化晶粒法的仿真与分析

ECAP(Equal Channel Angular Extrusion)方法，是实现材料纯剪切变形的有效方法。本文采用有限元（FEA）分析软件ANSYS对Al的挤压过程进行仿真与分析。分析结果表明：外切角Φ、圆角半径、试样与凹模之间的摩擦系数、凹模本身的特性（如弹性模量、泊松比等）等等，对材料的变形量都有不同程度的影响。     

A Novel Channel Predictor Based on Constrained Hidden Markov Model

1　Introduction　Linkadaptationtechniqueisnowwidelyrecognizedasakeysolutiontoincreasethespectralefficiencyofwire lesssystems[1～ 3] .GPRS ,EDGE ,cdma2 0 0 0andWCDMAallincludelinkadaptationasameanstopro videhigherdatarates[4～ 5] .Torealizethepotentialoflinkadaptation ,reliablechannel predictionisneces sary[6 ] .　Therearemanydifferentchannelpredictionmethodsavailablenow ,suchasLongRangePrediction(LRP) [6 ] ,predictionbasedonsubspacesignalprocess ingalgorithms[7] ,predictionbasedonFinit…     

Determination of Boundary Shear Stress and Reynolds Shear Stress in Smooth Rectangular Channel Flows

A method for computing three-dimensional Reynolds shear stresses and boundary shear stress distribution in smooth rectangular channels is developed by applying an order of magnitude analysis to integrate the Reynolds equations. A simplified relationship between the lateral and vertical terms is hypothesized for which the Reynolds equations become solvable. This relationship has the form of a power law with an exponent of n = 1, 2, or infinity. The semiempirical equations for the boundary shear distribution and the distribution of Reynolds shear stresses are compared with measured data in open channels. The power-law exponent of 2 gave the best overall results while n=infinity gave good results near the boundary.     

Multi-User MIMO Mobile CDMA Uplink System Employing Turbo Coding and Joint Detection Through a Multipath Rayleigh Fading Channel

In this paper, a generalized multiple-input multiple-output (MIMO) antenna system that can be fitted to the uplink of a wireless communication system is considered for the general case of multi-user. At the transmitter, the information bits are Turbo coded, then interleaved and passed through a serial-to-parallel converter. The channel is assumed bad urban suffering from multipath Rayleigh fading resulting in inter-symbol and multiple access interferences (ISI and MAI). At the front-end of the receiver, a number of receiving antennas are used followed by a joint multi-user estimator based on the Minimum Mean Square Error Block Linear Equalizer (MMSE-BLE).Computer simulations demonstrate a significant performance improvement in both single user and multi-user cases.This paper depends in parts on that presented at the 11th European Wireless Conference, Cyprus, Nicosia, pp. 187–192, April 2005. Yasmine A. Fahmy was born in Guiza, Egypt, on June 4, 1976. She received the B.Sc., M.Sc. and Ph.D. degrees in Communication and Electronics engineering from Cairo University, Egypt on 1999, 2001 and 2005 respectively. She is presently an assistant professor at Cairo University, Egypt. Her current field of interest is wireless communication and channel estimation. Hebat-Allah M. Mourad received her B.Sc., M. Sc. and Ph.D. degrees in electrical communication engineering from Cairo University, Egypt, in 1983, 1987 and 1994 respectively. Since 1983, she has been with the Department of Electronics and Communications, Faculty of Engineering, Cairo University, and is currently associate professor there. Her research interests include optical fiber communications, mobile and satellite communications. Emad K. Al-Hussaini received his B.Sc degree in Electrical Communication Engineering from Ain-Shams University, Cairo, Egypt, in 1964 and his M.Sc and Ph.D. degrees from Cairo University, Giza, Egypt, in 1974 and 1977, respectively. From 1964 to 1970, he was with the General Egyptian Aeroorganization. Since 1970, he has been with the Department of Electronics and Communications, Faculty of Engineering, Cairo University, and is currently professor there. He was a research fellow at Imperial College, London, UK, and at the Moore School of Electrical Engineering, University of Pennsylvania, Philadelphia, PA, USA, in the academic years 1976/1977 and 1981/1982, respectively. In 1990, he received the Egyptian national encouragement award for outstanding engineering research. He has written several papers for technical international journals and conferences. His research interests include signal processing, fading channel communication, modulation, and cellular mobile radio systems. Dr Al-Hussaini is a senior member of IEEE. He is listed in Marquis Whos Who in the World and in the IBC (International Biographical Center, Cambridge) for outstanding people of the 20th century.     

带有块间串扰MC-CDMA的时域信道估计和多用户检测

本文把带有IBI的MC-CDMA系统等效解释为特殊的直接序列码分多址（DS-CDMA）系统，并给出了相应的时域信道估计方法和时域线性最小均方误差（MMSE）多用户检测方法。仿真实验表明了本文方法的性能。     

基于参考模型的自适应话音处理

本文讨论了一种带有参考通道的自适应话音消噪滤波器原理，该滤波器采用最小均方差(心幅)算法。将此滤波器应用于复杂噪音背景的话音信号提取，能很好地抑制背景噪声，从而获得清晰的话音信号。     

The application of microencapsulated phase‐change materials to nylon fabric using direct dual coating method

The fabrication of functional textiles able to provide thermal regulation and comfort for the body has attracted increasing interest in recent years. This research investigated fabric coatings containing energy absorbing, temperature stabilizing, phase‐change material microcapsules (PCMMcs), and their methods of application. Specifically, a coated fabric was directly prepared by a dual‐type coating method, in which the PCMMcs were dispersed in a polyurethane coating solution with no binder. The thermal performances of the dual‐coated samples were evaluated by differential scanning calorimetry, and their physical characteristics were examined by scanning electron microscopy, thermal vision camera, porosity, water vapor transmission rate (WVTR), and water entry pressure (WEP) analyses. Furthermore, the microclimate characteristics of the thermally enhanced fabrics were investigated under experimental conditions using a human‐clothing‐environment (HCE) simulator system. The study results confirmed the superior performance of the dual‐coated fabrics in terms of thermal regulation and body comfort, compared with those coated by the dry or wet coating method, because of the improved WEP, WVTR, and thermal performance. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

曲流河沉积亚相的地震识别方法

本文提出利用三维地震资料相干数据分析研究曲流河沉积相的方法，其优点是在地质分析的基础上，对沉积体系有较为明显的识别特征，且在钻井较少的地区尤为实用。该方法在济阳拗陷东北部上第三系应用中取得了较为明显的效果。     

Numerical characterization of a microscale solid-oxide fuel cell

In this study, a single unit of planar micro-solid-oxide fuel cell (μSOFC) is investigated numerically to evaluate the influences of flow channel design, oxygen composition, and thermal operating conditions on cell performance. Four flow channel designs are examined under the co-flow configuration: serpentine, double serpentine, rod bundle, and oblique rib. For all designs, the contacts areas of interconnect to electrodes are kept consistent to maintain the ohmic losses at the same level. To characterize the mass transport effects, there are three different compositions, 100% O₂, 50% O₂/50% N₂ and air, fed to the cathode inlet. Different thermal conditions, adiabatic and isothermal, are applied to the outer boundary of the μSOFC and the results are compared. The outcomes suggest that both thermal conditions and oxidant composition show remarkable influences on μSOFC performance. Under adiabatic conditions, the rise of cell temperature causes a decrease in reversible voltage, deteriorating the overall cell competence. When oxygen is diluted with nitrogen, local gas diffusion becomes dominant to the cathode reaction. Bulk flow, on the other hand, plays a minor role in cell performance since there is little deviation in the polarization curves for all flow channel designs, even at high current densities. For comparison, the flow visualization technique is employed to observe the transport phenomena in various flow channel designs. The flow patterns are found to resemble the concentration distribution, providing a useful tool to design μSOFCs.     

过程控制级模拟轧钢系统的研制及在热轧试车中的应用

宝钢集团上海第一钢铁有限公司(后面简称一钢)新建的不锈钢工程1780热轧项目中,为了能在较短周期内完成所有的应用软件开发与测试任务,特别研制了模拟轧钢功能。本论文主要阐述利用计算机的集成思想,结合热轧工艺,来开发模拟轧钢功能,以及利用模拟轧钢进行现场各种情况的模拟测试。