The Effective Potential in Device Modeling: The Good, the Bad and the Ugly

We discuss the use of the effective potential to incorporate quantum effects in device models. While threshold shifts and charge set-back are handled well, tunneling is not well handled by this approach, or by any other local potential approach.     

地方电视台创建品牌的对策思考

品牌是企业竞争致胜的法宝,对电视行业同样如此,地方电视台要在竞争中求发展必须创立自己的品牌栏目。阐述了实施品牌战略对于地方台生存发展的重要意义和价值,对地方台创品牌难的原因以及创立品牌栏目的有效途进行了探讨。     

Efficient Internet Multicast Routing Using Anycast Path Selection

A novel efficient and dynamic multicast routing protocol based on anycast routing techniques is presented. The contributions of the protocol differ from well-known shared-tree systems in two aspects: (1) Off-tree anycast routing: The nodes in the shared tree are formed into a virtual anycast group and multicast sources use anycast routing to select a better path from the source to one router in the group to achieve short delay and fault-tolerance. (2) On-tree dynamic routing: The shared-tree approach is extended with capability of alternative path selections. If a node becomes absent from the shared tree, some predefined backup path(s) is (are) used to bypass the node and enable dynamic multicast routing to continue. The protocol requires only the routers near the faulty node to be reconfigured, thus reducing the runtime overhead as compared with global reconfiguration. The simulation data demonstrates the efficiency of our routing protocol.     

A Stochastic Neural Model for Fast Identification of Spatiotemporal Sequences

In this Letter, a new approach to build a neural model for the fast identification of spatiotemporal sequences is proposed. Such a model, the Stochastic Neural Sequence Identifier (SNSI), is simple and rapidly learns and identifies a given sequence. The SNSI receives as input several patterns belonging to a particular spatiotemporal sequence and produces as output a label for the sequence identified and a probability of this classification being correct. The SNSI is able to identify a sequence from patterns learned during training or novel ones, i.e., combinations of the sequence items distinct from those belonging to the trained set. The SNSI was tested on a 2D set of both closed and open trajectories with varying levels of complexity. The results suggest that the SNSI is able to recognize all the patterns presented in the training and most of the novel patterns used for testing.     

SAT Local Search Algorithms: Worst-Case Study

Recent experiments demonstrated that local search algorithms (e.g. GSAT) are able to find satisfying assignments for many hard Boolean formulas. A wide experimental study of these algorithms demonstrated their good performance on some inportant classes of formulas as well as poor performance on some other ones. In contrast, theoretical knowledge of their worst-case behavior is very limited. However, many worst-case upper and lower bounds of the form 2 ⁿ (<1 is a constant) are known for other SAT algorithms, for example, resolution-like algorithms. In the present paper we prove both upper and lower bounds of this form for local search algorithms. The class of linear-size formulas we consider for the upper bound covers most of the DIMACS benchmarks; the satisfiability problem for this class of formulas is NP-complete.     

场论中泛函积分表述中的正则对称性

对场采用泛函积分量子化,从正则变量表述的Green函数的生成泛函出发,分别导出了用非奇异拉氏量和奇异拉氏量描述的系统在相空间中的广义Ward恒等式,指出一般情况下奇异系统量子正则方程与Dirac猜想给出的正则方程是不同的,讨论了声子、电子和光子系统的奇异拉氏量描述,导出了该系统Green函数的生成泛函,给出了正则形式的广义Ward恒等式的初步应用。     

复杂载荷历程下疲劳寿命的预测方法

近年来局部应力-应变法在疲劳寿命预测中,越来越受到人们的高度重视。但普通的Neuber局部应力-应变法对于每一名义应力变程都需要建立新的坐标原点,并解非线性方程组。为此本文对其算法技巧进行了研究。算例表明,本文提出的新算法,能保证足够精度,程序得以简化,运算速度大幅度提高。     

无线本地环路技术与应用

本文简述了无线本地环路系统的特点,采用的技术以及目前在世界各国的应用发展情况。     

一类n维Lotka—Volterra模型的稳定性特征

本文给出n维Lotka-Volterra合作系统局部渐近稳定性和全局稳定性的判别条件,并证明该系统正平衡位置的稳定性特征:局部渐近稳定性和全局稳定性是等价的.     

圆柱齿轮啮合过程齿根应力数值计算方法研究

本文提出了一套在微机上计算机直齿与斜齿圆柱齿轮啮合过程齿根应力分布的方法。使用者只需输入一对齿轮副的几何参数和结构参数，计算机将自动完成齿轮副的三维有限无风格部分。通过齿面坐标系及坐标变换矩阵，一次求出核齿轮副的齿向载荷分布齿间载荷分本。一步运用 齿根局部网络密化，可详细研究轮在啮合过程中的齿根应力分布。编制的软件配有较强的数据前，后处理手段，便于使用。文中以一对斜齿轮副为例进行了说明，计算结果与