Hexagonal metric for linear codes over a finite field

This paper consider Hexagonal-metric codes over certain class of finite fields. The Hexagonal metric as defined by Huber is a non-trivial metric over certain classes of finite fields. Hexagonal-metric codes are applied in coded modulation scheme based on hexagonal-like signal constellations. Since the development of tight bounds for error correcting codes using new distance is a research problem, the purpose of this note is to generalize the Plotkin bound for linear codes over finite fields equipped with the Hexagonal metric. By means of a two-step method, the author presents a geometric method to construct finite signal constellations from quotient lattices associated to the rings of Eisenstein-Jacobi (EJ) integers and their prime ideals and thus naturally label the constellation points by elements of a finite field. The Plotkin bound is derived from simple computing on the geometric figure of a finite field.     

Multi-granularity evolution analysis of software using complex network theory

Software systems are a typical kind of man-made complex systems. Understanding their evolutions can lead to better software engineering practices. In this paper, the authors use complex network theory as a tool to analyze the evolution of object-oriented (OO) software from a multigranularity perspective. First, a multi-granularity software networks model is proposed to represent the topological structures of a multi-version software system from three levels of granularity. Then, some parameters widely used in complex network theory are applied to characterize the software networks. By tracing the parameters’ values in consecutive software systems, we have a better understanding about software evolution. A case study is conducted on an open source OO project, Azureus, as an example to illustrate our approach, and some underlying evolution characteristics are uncovered. These results provide a different dimension to our understanding of software evolutions and also are very useful for the design and development of OO software systems.     

A note on the model reference adaptive control of linear parabolic systems with constant coefficients

The problem of constructing a model reference adaptive control law for an uncertain 1-dimensional parabolic system with one constant coefficient is considered in this paper. Adaptive control law are obtained by Lyapunov redesign method. The energy method for parabolic systems and the Agmon’s inequality are applied in the analysis, which leads to a stronger result than that of Hong and Bentsman (Automatica, 1994).     

Design efficiency for minimum projection uniformity designs with two levels

The objective of this paper is to study the issue of design efficiency for minimum projection uniformity designs. The results show that for orthogonal arrays with strength two, the minimum projection uniformity criterion is a good surrogate for the design efficiency criterion proposed by Cheng, Deng and Tang (2002).     

Upwind finite volume element methods for one-dimensional semiconductor device

A fully discrete implicit Euler upwind finite volume element method is derived and studied for one-dimensional semiconductor device. Upwind scheme is introduced to deal with the convection-dominated diffusion equations in the semiconductor model. With different time steps for the electrostatic potential and the other unknown quantities, the computational procedure of the method is obtained. The local mass conservation laws are preserved under the framework of the upwind finite volume element schemes. A first-order accuracy in the L ²-norm is proved. Numerical experiments are given to validate the usefulness and efficiency of the method.     

InP单晶表面势垒高度与表面态密度的光伏测算

应用变温光伏方法测定了Ｎ型低阻ＩｎＰ单晶的表面势垒高度，进而分析、计算了简并化的ＩｎＰ单晶表面态密度。     

桥式起重机金属结构疲劳计算新方法

本文介绍一种计算桥式起重机金属结构疲劳强度的新方法，探讨了结构应力幅的形成和分布，并以实例说明计算的全过程．     

倾斜中厚多层低品位难采矿体的采矿方法

针对川口钨矿杨林坳矿区难采矿体的开采技术条件，经优选采用爆力运搬阶段矿房采矿法，成功地解决了该矿区占总工业储量６０％以上（质量分数）的倾斜、中厚、多层、低品位难采矿体的开采方法，也为其它矿山同类型矿体开采提供了科学技术依据和工艺经验。     

双（N－氰基亚氨基二硫代甲酸）合镍（Ⅱ）酸－（5，7，7，12，14，14－六甲基－1，4，8，11－四氮杂环十四－4，11－二烯）合镍（Ⅱ）的合成与晶体结构

通过盐消除反应合成了双核镍的加合物［Ｎｉ（ｈｍｔａｄｅ）］［Ｎｉ（ｃｄｃ）２］，其中ｈｍｔａｄｅ＝５，７，７，１２，１４，１４－六甲基－１，４，８，１１－四氮杂环十四－４，１１－二烯，ｃｄｃ＝Ｎ－氰基亚氨基二硫代甲酸根。用元素分析、红外光谱、电子光谱和磁化率对它进行了表征。用Ｘ－射线测定了单晶的晶体结构，晶体属单斜晶系，空间群为Ｃ２／Ｃ，晶胞参数ａ＝１１．８８３（２）Ａ，ｂ＝１１．７５３（２）Ａ，Ｃ＝２０．４８２（４）Ａ，ａ＝９０°，β＝１００．１９（１）°，ｒ＝９０°，Ｖ＝２８１５．４Ａ３，Ｍ＝６２８．１９，Ｄｘ＝１．４８２ｇ／ｃｍ２，Ｚ＝４，Ｒ＝０．０４７，Ｒｗ＝０．０５４。正离子的［ＮｉＮ４］为近似平面构型，整个正离子的外形是马鞍型；负离子的［ＮｉＳ４］为绝对平面。在Ｎ（１）和Ｎ（１１）之间形成了氢键，使得加合物呈一维线性链结构。     

单频散斑光栅膜研测面内位移场

本报道了利用作研制的一种新的光学元件－单频散斑光栅模进行面内位移场测量的方法及原理。