学科交叉融合对计算机基础教学的新挑战

学科交叉融合是现代世界一流大学注重培养的新思路,也越来越受到普通高校教学研究者们的重视。《大学计算机基础》课程则是高校教改的重点和难点。就如何在《大学计算机基础》课程中引入新的教学思路,让学科交叉融合能在高等教育的开展之初就能融入到大学生的学习和研究中,进行部分实践和探索。随着计算机在现代科学研究中的重要性越来越突出,计算机教学改革势在必行。     

基于Host Link FINS协议的PLC远程通信

以欧姆龙公司CP1H型号的PLC为应用背景,设计了基于Host Link FINS协议的PLC设备远程监控系统.该文提出了基于串口的远程通信方案,并且详细分析了Host Link FINS协议的结构和指令格式,用MFC实现了监控软件的设计,完成监控软件与欧姆龙PLC的数据通信功能,实现监控软件对PLC的远程监控.经过现场的测试和运行,该监控系统稳定可靠,性能较高.     

Studies on membrane formation mechanism by the light transmission technique. I

New parameters, light transmission rate and minimum light transmissions, are proposed. These two parameters reflect the characteristics of the membrane‐forming system and the formation process of the membranes by phase inversion. The relationship between the light transmission and the porous structure of the membrane can be explained by the geometrical optics principles. Variation of the two parameters combining Reuvers's phase separation theory provided a convenient analytical method to predict effectively membrane morphologies. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 174–181, 2003     

Non-Isothermal crystallization of isotactic polypropylene in dotriacontane. II: Effects of dilution,cooling rate,and nucleating agent addition on growth rate

Non-isothermal crystallization growth rates of nucleated and non-nucleated isotactic polypropylene (iPP) in dotriacontane were determined experimentally by thermal optical microscopy. Adipic acid was used as the nucleating agent. The non-isothermal growth rates of the nucleated and non-nucleated systems were compared with experimentally determined isothermal growth rates. The Lauritzen and Hoffman growth rate equation, originally developed for isothermal crystallization, was modified to describe the non-isothermal growth. The modified Lauritzen-Hoffman equation was used to predict isothermal growth rates from non-isothermal crystallization for the nucleated and non-nucleated polymer-diluent mixtures. This study is the first to deal with polymer-diluent-nucleating agent systems vital to membrane production.     

X-Ray, Micro-Raman, Optical Absorption/Emission Studies of ErNbO4 Grown by Vapor Transport Equilibration

Vapor transport equilibration (VTE) treatments were performed on a Y-cut bulk Er (1.6 mol%)-doped congruent LiNbO₃ crystal and an X-cut pure congruent crystal, on one surface of which a 40 nm-thick film of erbium metal was coated before the VTE treatment. Scanning electron microscope, powder or single-crystal X-ray diffraction (XRD), polarized infrared absorption/emission of Er³⁺ as well as micro-Raman spectroscopy were used to study the two VTE crystals. The results are discussed in comparison with a corresponding as-grown bulk Er-doped crystal, calcined ErNbO₄ powder, and a locally Er-doped congruent LiNbO₃ crystal prepared by using the standard Er-diffusion technique. The experimental results show that the VTE treatment induces the formation of micrometer-sized ErNbO₄ precipitates with the crystallographic morphology of a flat polyhedron not only on the surfaces of both crystals but also in the bulk of the homogeneously Er-doped one. The optical absorption and emission studies show that the formation of the precipitates results in substantial spectral changes in both the 0.98 and 1.5 μm regions. The micro-Raman studies allow to resolve four additional Raman peaks around 800 cm⁻¹ in the E(TO) spectra of the two VTE crystals. These additional Raman peaks are associated with the characteristic vibrations with respect to the NbO₄³⁻ group. Characteristic XRD, optical absorption, and emission and Raman peaks for identifying the ErNbO₄ phase are proposed. Finally, the formation mechanism and light-scattering effect of the precipitates are discussed.     

Circulating fluidized bed combustion of a high-sulphur eastern canadian coal

Combustion tests were carried out with Minto coal in combination with three different limestones in the University of British Columbia (UBC) pilot scale (152 mm square x 7.3 m tall) circulating fluidized bed combustion (CFBC) unit. Operating conditions were chosen to be typical of those employed in large-scale CFBC power boilers. Recycling of fine particles captured by the secondary cyclone was found to be of considerable importance in increasing sulphur capture, enhancing combustion efficiency and reducing the amount of calcium sulphide in the solids residues. NO_x emissions increased as the Ca:S ratio increased. Local gas concentrations inside the reactor were strongly influenced by the core-annulus solids distribution patterns which characterize circulating fluidized beds.     

Scalable and leaderless Byzantine consensus in cloud computing environments

Traditional Byzantine consensus in distributed systems requires n ≥ 3f + 1, where n is the number of nodes. In this paper, we present a scalable and leaderless Byzantine consensus implementation based on gossip, requiring only n ≥ 2f + 1 nodes. Unlike conventional distributed systems, the network topology of cloud computing systems is often not fully connected, but loosely coupled and layered. Hence, we revisit the Byzantine consensus problem in cloud computing environments, in which each node maintains some number of neighbors, called local view. The message complexity of our Byzantine consensus scheme is O(n), instead of O(n ²). Experimental results and correctness proof show that our Byzantine consensus scheme can solve the Byzantine consensus problem safely in a scalable way without a bottleneck and a leader in cloud computing environments.     

浅谈面料再创造与服装设计

在服装设计过程中,面料的再创造已经成为彰显服装设计、创新能力的一项重要内容.分析了面料再创造的基本含义、方法以及其在服装设计过程中的具体运用,并简要阐述了面料再创造的多样性特征和丰富的表现形式.     

核电工程项目调试工期的影响因素与优化

调试启动工作是核电工程项目进度控制中非常重要的环节,对整个工程的顺利投入运行有着重要的作用。如果调试工期过长,则会导致核电工程不能按期交付使用,从而对整个核电工程的进度造成影响。主要探讨了核电工程项目调试工期的影响因素和优化措施。     

基于web的外贸企业资金流管理平台的设计

本文针对外贸型企业对外贸易服务流程中的资金流动和资金流管理中存在的问题,设计了一个基于Web的外贸企业资金流管理平台,实现跨地域、多角色、实时的资金流录入、统计和分析,使企业能够高效准确地管理业务和资金流,能够随时统计资金的流向以及分析盈利情况;着重论述外贸企业资金流管理需求、基于Web的系统框架设计、数据加密存储、加密传输、用户角色及权限控制等。