一种基于码本聚类的低复杂度用户选择算法

现有块对角化(BD)预编码系统用户选择算法较少考虑利用已选用户与剩余用户之间的关系来排除不可选用户.针对这点不足,给出了一种采用码本聚类的低复杂度用户选择算法( CodeGreedy算法).该算法采用弦距离刻画用户信道的相关性,以此为依据将用户划分到不同码本空间中,聚集在同一码本空间的用户信道具有较强的相关性,形成互斥...     

Comparison of image reconstruction by using near‐field and far‐field data for an imperfect conductor

Image reconstruction by using near‐field and far‐field data for an imperfectly conducting cylinder is investigated. A conducting cylinder of unknown shape and conductivity scatters the incident wave in free space and the scattered near and far fields are measured. By using measured fields, the imaging problem is reformulated into an optimization problem and solved by the genetic algorithm. Numerical results show that the convergence speed and final reconstructed results by using near‐field data are better than those obtained by using far‐field data. This work provides both comparative and quantitative information. © 2001 John Wiley & Sons, Inc. Int J RF and Microwave CAE 11: 69–73, 2001.     

三对角对称矩阵逆特征问题

In this paper, four inverse eigenproblems with giventhree eigenvalues and corresponding eigenvectors are considered, somenecessary and sufficient conditions under which there exists a uniquesolution for these problems are given. Furthermore some numerical algorithmsand some numerical experiments are given.     

铁道钢轨断面的计算机图象处理与仿真

利用计算机图象处理和仿真技术,对铁道钢轨断面进行快速检测与处理的研究。     

工业设计专业基础设计教学思考与探索

基础设计课程是工业设计专业从基础课程过渡到产品设计课程之间的桥梁,采用理论与实践相结合以实践教学为主的教学方法,理论环节以实例讲授为主,实践环节主要是专题设计训练,培养学生的观察、感受和把握的能力,着重于从纯粹的无目的的形态构成到实际产品设计的过渡,系统地训练产品设计的创意思维方法。在学习过程中运用基础课程的原理与方法,通过手工制作出有实用功能、形式美感兼备的产品雏形。     

Nanoparticle-based lift-off technique for ultra-thin nanoporous film preparation

Ultra-thin membrane with nanoscale through hole has great potential in biomedical applications, where precise controllability of porosity, pore size and film thickness is urgently required. The present work proposed a cost-effective way to prepare the ultra-thin nanoporous film with a promising controllability. Monodispersed nanoparticle, rather than photoresist, is used as the sacrificial material for this new lift-off process. By releasing the particles, holes can be achieved with predeter-mined characters. A 110 nm-thick nanoporous aluminum film with well-controlled pore＇s diameter was successfully fabricated to validate the technique. The technique has wider process window and better applicability than other nanofabrication methods.     

劝导技术及其设计评估的分析

劝导技术是利用计算机、设备及应用软件来影响人类想法及行为的技术。该文对劝导技术的发展及其现状进行了综述,并着重对劝导技术的可信度及其三类劝导技术应用结果通过心理学的角度进行了分析。系统生命周期是现代设计方法理念的一个重要概念,该文介绍了系统生命周期,并介绍了基于系统生命周期中的劝导技术的设计评估行为。该文为劝导技术产品研究设计分析提供了系统的理论的指导。     

专用集成电路入检测试系统

专用集成电路入检测试系统是根据《专用集成电路入检测试系统研制要求》的设备用途。被测对象的主要技术指标．测试系统的组成、功能殛主要技术指标制定。通过引入通用测试仪表组,运用GPIB总线控制等方法。开发研制了集成电路入检设备．该设备可对混合集成电路模块在常温条件下的技术指标进行测试。     

抓住机遇全面提升农业机械化水平

通过国家对农业"多予、少取、搞活"方针的贯彻,分析了当前大好有利时机,结合当地农机实际,提出了加快发展步伐,全面提升农业机械化水平,提高农业劳动生产力,改善农民生产、生活条件的重要技术措施.