深亚微米集成电路的快速时域仿真技术

随着深亚微米集成电路技术的发展，集成电路的规模越来越大，工作频率越来越高，并正朝着系统集成的方向发展，因而在模拟速度，模拟精度和可模拟的电路规模等各个方面对电路仿真技术提出了新的要求。近年来，各种新的电路仿真方法和仿真系统用相继脱颖百出，并将取代那些传统的，已经无法适应深亚微米技术发展的电路仿真器。     

Electronic properties of CuO2 planes

We study a 3-band model of CuO₂ with “bare bones” interactions: hopping from copper ions to nearest-neighbor oxygenst _pd only, a two-body interaction on the copper ionsU _dd only, and an overlap copper-oxygen parameter λ_pd. In the limitt _pd ∝U _dd ^1/2→∞, t^*=t _pd ²/2U _dd is the unit of energy with 8λ_pd ² as the only parameter of significance. If the two-body interaction is invariant under particle-hole interchange, the low-lying states (energy O(t^*)) can be described by conserved particles and can all be classified. They are quite distinct from the high-lying states (energies O(U _dd)). The dynamics of the conserved fermion-like elementary particles are well described by a modifiedt-J model with extended hopping and nearest-neighbor superexchange attraction. This is a scenario known to be favorable to high-temperature superconductivity, but it must be noted that both the hopping range and the exchange are functions of 8λ_pd ². Moreover, if the Hamiltonian isnot invariant under particle-hole interchange the dynamics becomes much more complex and possibly more inimical to high-temperature superconductivity. This may provide an explanation for the deleterious effect on superconductivity of very small concentrations of certain impurities.     

Minimal communication cost software construction in the Internet environment

This paper investigates the issue of building software in the Internet environment, where local area network (LAN) based systems are interconnected by links with different bandwidth and do not share file systems. The software is modeled as a directed acyclic graph. Each node in the graph represents a logical step in processing the software while the edges describe the order of execution. The problem is to construct the software at a particular LAN with minimum Internet communication cost. An optimal polynomial algorithm, SOFTCON, with time complexity is presented, where and are the number of nodes and edges in the graph describing the software respectively, is the number of LANs in the Internet environment, and is the time complexity of the network flow algorithm on the flow network with nodes and edges transformed from the directed acyclic graph of the software. Received: 6 December 1995 / 1 May 1996     

Analysis of aperture-coupled microstrip antenna using thesegmentation method

The authors present an original analysis of an aperture-coupled microstrip antenna. The theory is based on the segmentation method, which considers the patch as a multiport network whose impedance matrix is deduced from a hybrid matrix, and the use of analytical expressions of the cavity admittance at the slot centre. The theory is presented for the first time, and the theoretical results are in good agreement with previous published measurements     

On solving constrained optimization problems with neural networks:a penalty method approach

Deals with the use of neural networks to solve linear and nonlinear programming problems. The dynamics of these networks are analyzed. In particular, the dynamics of the canonical nonlinear programming circuit are analyzed. The circuit is shown to be a gradient system that seeks to minimize an unconstrained energy function that can be viewed as a penalty method approximation of the original problem. Next, the implementations that correspond to the dynamical canonical nonlinear programming circuit are examined. It is shown that the energy function that the system seeks to minimize is different than that of the canonical circuit, due to the saturation limits of op-amps in the circuit. It is also noted that this difference can cause the circuit to converge to a different state than the dynamical canonical circuit. To remedy this problem, a new circuit implementation is proposed.     

垂直平行束状孔爆破模型试验与分析

垂直平行密集束状孔落矿有底柱崩落法是一种新的采矿方法。通过爆破模型试验，测试爆破应力，观察分析爆破效果，探求最佳布孔形式，选择最优爆破孔网参数。试验结果表明：用平行束状孔取代扇形落矿，改善了爆破效果，简化了采场结构，减少了采切工程量。     

工业产品的艺术造型与技术美学

本文从技术美学的角度，广义的介绍了工业产品艺术造型的基本方法，着重从美学原则和色彩设计两方面论述产品造型设计的手法，以及技术美学在产品造型设计中的基本应用。     

The application of transmission-line modelling to the simulation ofan induction motor drive

The simulation of a complete induction motor drive is presented. The entire network is modelled using the transmission-line modelling (TLM) technique. The network is split into three sections which are solved independently and are joined together by link transmission-line models. Advantages of this approach are the explicit nature of the algorithm which remains unaltered irrespective of the network topology, unconditional stability, and straightforward modelling of switching elements. Results are presented for a complete drive which illustrate the capabilities and flexibility of the simulation technique