加强地质工作 尽快实现鄂东南地区找矿新突破

鄂东南地区列入中国“十一五“地质勘查规划16个重点金属成矿区带之一的长江中下游成矿带内的铜铁找矿远景区。这无疑给鄂东南地区实现找矿新实破带来了机遇。本文论述了实现鄂东南地区找矿新突破的关键因素是科技和人才;找矿新突破主攻方向是大中型矿床深部及外围、经综合研究筛选的重点成矿远景区(段),主攻矿种铜铁、兼顾金和多金属;具体工作中必须抓好多学科及多技术方法的地质找矿综合研究、加强地质资料和老年科技人员的“二次“开发、加大投入及加强验证等环节。     

圆环链链轮传动力学模型的建立与计算方法

建立了清晰的圆环链—链轮传动的力学模型 ,识别了决定传动形式的齿形、自锁、啮入过程等关键细节问题 ,并探讨了在这一力学模型下借用图形学专业软件来计算链环受力的方法 ,突破了传统分析轻重不分不建理论模型的缺陷 ,能做到定量计算     

激光星间链路中天线扫描捕获技术实验室模拟研究

对激光星间链路中的天线扫描捕获技术进行了理论分析和模拟实验研究。首先建立了天线扫描捕获理论模型 ,在此基础上对影响系统捕获性能的各主要参量之间关系进行了数值仿真分析。设计实现了一套天线扫描捕获实验室模拟系统 ,通过模拟实验对部分数值分析结果进行了验证 ,实验结果与数值分析结果基本符合。     

Eliminating duplication with the hyper-linking strategy

The efficiency of almost all theorem proving methods suffers from a phenomenon called duplication of instances of clauses. In this paper, we present a novel technique, called the hyper-linking strategy, to eliminate such duplication. This strategy is complete for the full first-order predicate calculus. We show the effectiveness of this strategy by comparing it with other proving methods. We give empirical evidence that both the Davis-Putnam procedure and the hyper-linking strategy are comparable to each other and better than other common theorem proving strategies on propositional calculus problems. The fact that the Davis-Putnam procedure is faster than resolution and other common methods on propositional problems seems not to be appreciated by a large segment of the theorem proving community. Also, we give empirical evidence that the hyper-linking strategy is better than other common theorem proving methods on near-propositional problems like logic puzzles. We attempt to explain the superior behavior of the hyper-linking strategy and the Davis-Putnam procedure by examining the kinds of duplication that can occur during the search with the different methods. In addition, we show the completeness of the hyper-linking strategy combined with several support strategies.This research was partially supported by NSF under grant CCR-8802282.     

Extended Domain of Existence for PSCs in Superconductors

By means of nanosecond pulse techniques, we have studied the current-induced dissipation in one-dimensional superconducting bridges, namely, metallic and high-T _c films. It is well known that narrow strips dissipate through phase-slip centers (PSC) close to T _c, or hot spots (HS) at low T, rather than by flux flow. When driven by step pulses of current, PSC give stable voltages, while HS produce a voltage linearly changing with time. By using two-step pulses of current, we have studied the decay of a HS into another HS, or a PSC, or into a zero-resistance state. It was thus found possible to reach the PSC state at arbitrary low temperatures.     

Viscosity of ionomer gels

We study the viscosity behaviour of metal sulphonate- (or metal carboxylate-) containing ionomers in solution with non-polar solvents; at relatively low polymer concentration these ionomer solutions show an unusually large thickening behaviour, due to the association of the metallic groups. By regarding the ionomer system as a polymer solution with transient crosslinks, an expression is derived from the viscosity of the sulphonated polymer in terms of the viscosity of the corresponding non-sulphonated polymer and the average number of crosslinks associated with any chain.     

“在线测量”及其进展

本文从在线测量的含义到历史背景，从主要环节到基本类型，从实际应用到发展趋势，以及从我国在线测量的现状、存在问题到今后发展的重点等，全面、深入地分析和论述了在线测量及其进展。文中关于在线测量的分类，即将在线测量分为“越线报警”、“参数监测”、“过程监控”和“智能化”等基本类型，亦是作者最先概括并提出的。     

A New CMOS Current-Mode Multiplexer for l0 Gbps Serial Links

This paper presents an in-depth study of the pros and cons of voltage-mode multiplexers for Gbps serial links and exploits the advantages of multiplexing in current domain. In addition, it proposes a new fully differential CMOS current-mode multiplexer where a high multiplexing speed is achieved by multiplexing at a low-impedance node. Multiplexing speed is further improved by inductive shunt peaking with active inductors. The differential configuration of the multiplexer minimizes the effect of common-mode disturbances, particularly those coupled from the power and ground rails. The flow of the output currents in the opposite directions minimizes the effect of electro-magnetic interference from channels, making the multiplexer particularly attractive for high-speed data transmission over long interconnects and printed-circuit-board (PCB) traces. The proposed multiplexer draws a constant current from the supply voltage, thereby minimizing both switching noise and noise injected to the substrate. A fully differential CMOS current-mode 8-to-l multiplexer has been implemented in TSMC’s 1.8 V 0.18 μm CMOS technology and analyzed using Spectre from Cadence Design Systems with BSIM3.3v device models. Simulation results demonstrate that the multiplexer offers sufficiently large eye-opening when multiplexed at 10 Gbps.Jean Jiang received the B.Eng. degree in Electrical Engineering from Wuhan University of Technology, Wuhan, China in 1995. From 1999 to 2001, she worked for Ericsson Global IT Services where she was a technical staff to maintain computer networks. Since 2002, she has been a research assistant with the System-on-Chip research lab of Ryerson University. She is currently a M.A.Sc candidate under the supervision of Dr. Fei Yuan in the Department of Electrical and Computer Engineering, Ryerson University, Toronto, Canada. Her research interests are in analog CMOS circuit design for high-speed data communications. She was awarded the Ontario Graduate Scholarship (OGS) in 2003–2005 for academic excellence.Fei Yuan received the B.Eng. degree in electrical engineering from Shandong University, Jinan, China in 1985, the MASc. degree in chemical engineering and PhD. degree in electrical engineering from University of Waterloo, Waterloo, Ontario, Canada in 1995 and 1999, respectively.During 1985–1989, he was a Lecturer in the Department of Electrical Engineering, Changzhou Institute of Technology, Jiangsu, China. In 1989 he was a Visiting Professor at Humber College of Applied Arts and Technology, Toronto, Canada. During 1989–1994, he worked for Paton Controls Limited, Sarnia, Ontario, Canada as a Controls Engineer. Since July 1999 he has been with the Department of Electrical and Computer Engineering, Ryerson University, Toronto, Ontario, Canada, where he is currently an Associate Professor and the Associate Chair for Undergraduate Studies and Faculty Affairs. He is the co-author of the book “Computer Methods for Analysis of Mixed-Mode Switching Circuits” (Kluwer Academic Publishers, 2004, with Ajoy Opal). Dr. Yuan received an “Excellence of Teaching” award from Changzhou Institute of Technology in 1988, a post-graduate scholarship from Natural Science and Engineering Research Council (NSERC) of Canada during 1997–1998. He is a senior member of IEEE and a registered professional engineer in the province of Ontario, Canada.     

基于冗余链路的无尺度网络拓扑结构优化研究

目前,随着规模的不断扩大,很多网络呈现出了“无尺度”的特性。然而,无尺度网络有其特有的脆弱性,如果网络的集散节点遭到攻击,网络将很容易崩溃。文中提出了基于冗余链路的无尺度网络拓扑结构优化算法,将集散节点的邻接网络构造成环形立交结构,保证剩余网络节点间的通信。仿真结果表明,该算法能够较好地提升网络的抗攻击能力。     

微波光链路的噪声系数分析

微波光链路(MPL)是利用光纤传输微波信号,与传统的射频链路相比具有带宽大、损耗小、质量轻、抗电磁干扰等优势,但也存在噪声系数较大的问题,从而影响链路的动态范围.建立了直接调制的微波光链路模型,在不考虑频响的情况下推导出链路固有增益和噪声系数的表达式,研究了激光器的转换效率、光纤的损耗和相对强度噪声(RIN)对链路噪声系数的影响.还建立了链路频响的模型,推导出固有增益与频率关系的表达式,分析仿真了频率对链路固有增益和噪声系数的影响,并与实验结果进行了比较.