一类求解非线性规划的修正斜边界滤子方法

本文给出一类修正的斜边界滤子方法,结合序列二次规划方法求解非线性规划问题.我们将目标函数方向和约束违反度方向均设置了斜边界,用以构造充分减少条件.同时,和经典滤子相比,新的滤子接受试探点更加灵活,改善了迭代点的被接受机会.新的滤子也具备经典滤子的“包含性”,并被用于可行恢复项中.在较弱的条件下,可以得到全局收敛性.最后,给出了数值实验结果.     

LEAP EFFECTS AMONG ROBUST ROOT TRAJECTORIES

The set of closed-loop eigenvalues in the presence of the worst uncertainty is termed robust root trajectory. The open-loop gain or some other system parameter is changed monotonically. The admissible uncertainties are considered along their envelope. The worst uncertainty is denoted as that one where a specified function of the eigenvalues leads to the maximum disadvantageous effect on the closed-loop stability performance. Leaps in the dynamic behavior occur even for infinitesimally small changes in the gain parameter when system uncertainties are considered that are located especially at their bounds.     

Effects of low‐frequency drain termination and injection on nonlinear amplifier performances

Low‐frequency parameters have important effects on the nonlinear performances of power amplifiers. Injection at the output of a low‐frequency‐voltage device, following the signal envelope, is proposed. Two‐tone simulations, measurements using the principle of a low‐frequency active load‐pull system, and implementation of the technique are presented. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005.     

黑球温度对房间热舒适性的影响分析

本文通过分析黑球温度计的工作原理,依据青藏铁路某被动太阳房试验数据研究,分析了太阳房室内黑球温度、空气温度和围护结构内表面温度之间的关系,提出用室内黑球温度和室内空气温度以及围护结构内表面温度的温差来评价房间热舒适性的方法和依据。     

电子商务中SET协议的实现与分析

SET是目前在电子商务中一种安全电子交易协议,尤其在网上交易中有着广泛地应用,是大多数在线支付所采用的交易协议。这里探讨了SET协议的作用、技术实现、工作流程、认证系统的实现等;对它的一些典型应用进行了描述;并且对SET的工作效率、安全性进行了分析。     

连续波半主动雷达制导空空导弹截获跟踪距离计算

分析了连续波半主动雷达制导导弹导引头工作电磁环境和对武器系统攻击区的影响，建立了热噪声和杂波干扰环境下导引头截获距离方程，分析推导了直波泄漏干扰，地杂波干扰的计算公式，并在此基础上给出了导弹允许攻击区计算公式。     

在VC++中用CryptoAPI保证安全数据通信

Microsoft的加密应用程序接口CryptoAPI使开发人员可以在应用程序中加入强大的保证数据通信安全性的功能。本文研究了在VC 应用程序中利用CryptoAPI实现数字签名和验证、数据加密和解密等安全数据通信的关键技术,并给出了实现的方法。     

Development of HAM tool for building envelope analysis

Moisture-related building envelope failures have resulted in costly rehabilitation in various regions of North America. To advance building envelope design towards an engineering approach and reduce the occurrence of future failures, an advanced numerical tool was developed, in conjunction with an extensive full-scale experiment, to investigate hygrothermal performance of various wood-frame wall assemblies. Major features of the tool are multi-dimensional and transient coupling of heat and moisture transport; natural air convection integrated in hygrothermal simulation through Darcy–Boussinesq approximation; heat transfer by conduction and convection of sensible and latent heat; moisture transport by vapor diffusion, capillary suction and convection; material database of common building materials in North America; experimental settings or weather data as boundary conditions; and moisture added in the building envelope to simulate the wetting process. The numerical tool achieves good compliances to the benchmarking cases of the HAMSTAD project, and its predictions have shown good agreement with data from the full-scale wall experiment. The numerical tool employs the commercial finite-element software to solve the governing equations. This approach provides building science researchers the flexibility to modify, maintain and share their modeling work efficiently.     

夏热冬暖地区围护结构节能技术应用调研

建筑围护结构的节能是夏热冬暖地区建筑节能工作的重点。目前,建筑行业整体关于存量建筑的围护结构节能技术的应用情况不十分清晰。为此,采用能源审计方法对深圳、厦门和柳州三座典型城市的807栋建筑进行了调研和统计分析。调研样本建筑中,2005年以前建设的建筑占有较大比例,为65.93%;普通玻璃的应用数量为49.03%,而Low-E玻璃实际应用只有9.12%;建筑遮阳主要形式为内遮阳,外遮阳应用比例仅为9.13%,还有20.19%的建筑没有任何遮阳形式,其中商场达到37.5%。在夏热冬暖地区,针对存量建筑墙体材料热工性能的改善应为重点,并加大Low-E玻璃和外遮阳技术的推广力度。     

M元多码MC-CDMA系统信号包络特性分析

针对扩频通信中的M元多码系统,结合OFDM技术特点,提出了一种新的M元多码MC-CDMA系统。在分析系统基本原理基础上,建立了系统信号模型,对系统发射信号包络特性进行了分析研究,推导出系统信号包络公式,讨论了系统多码分路数与系统包络以及系统PAPR的关系。对系统不同分路数情况下包络状态进行了仿真,结果表明M元多码MC-CDMA系统发射信号包络和PAPR受多码分路数以及扩频序列的影响。