2D Bi2O2Te Semiconductor with Single-Crystal Native Oxide Layer

Following logic in the silicon semiconductor industry, the existence of native oxide and suitable fabrication technology is essential for 2D semiconductors in planar integronics, which are surface-sensitive to typical coating technologies. To date, very few types of integronics are found to possess this feature. Herein, the 2D Bi₂O₂Te developed recently is reported to possess large-area synthesis and controllable thermal oxidation behavior toward single-crystal native oxides. This shows that surface-adsorbed oxygen atoms are inclined to penetrate across [Bi₂O₂]_n²ⁿ⁺ layers and bond with the underlying [Te]_n²ⁿ⁻ at elevated temperatures, transforming directly into [TeO₄]_n²ⁿ⁻ with the basic architecture remaining stable. The oxide can be adjusted to form in an accurate layer-by-layer manner with a low-stress sharp interface. The native oxide Bi₂TeO₆ layer (bandgap of ≈2.9 eV) exhibits visible-light transparency and is compatible with wet-chemical selective etching technology. These advances demonstrate the potential of Bi₂O₂Te in planar-integrated functional nanoelectronics such as tunnel junction devices, field-effect transistors, and memristors.     

5种药用植物挥发油对仓库害虫生物活性的研究

研究了香薷、鹤虱等５种药用植物挥发油对仓虫的生物活性作用。结果表明,香薷挥发油的作用最为明显,它（剂量０２μＬ／ｇ）及其粗分离１＃～５＃样品（剂量００５μＬ／ｇ）均有效地抑制了试虫卵、幼虫及成虫的生长发育,从而减少了试虫Ｆ１代种群的发生,其中粗分离１＃样品作用尤为突出。香薷挥发油１＃～５＃样品的主要化学成分为４,５,６,７,８,８ａ－六氢－８ａ－甲基－２［１Ｈ］－奥酮（５２６４％）、百里香酚（３０５％）和一未定成分（２１９２％）。     

ARPO-2: An expert system for legal advice on the breach of building contracts

Although Berman and Hafner [Berman 1989, pp. 928–938] presented the possibility to adapt the model of reasoning of development of an expert system for medical diagnosis to the reasoning of a judge when he/she sentences criminals does not resemble the reasoning found in the decisions of physicians, mathematicians or statisticians.When a lawyer reasons, he/she not only looks for the solution of a case; he/she simultaneously looks for the bases on which his/her reasoning can rest [Galindo 1992, pp. 363–367]. That is to say, he/she not only needs to find the solution but moreover he/she has to find the references (laws, jurisprudence and bibliography) that allow him/her to argue the solution.In many cases, computer solutions to these reasoning processes have been made in a separated way: the solution to the cases using expert systems, and the search of documentation using information retrieval systems.This paper presents the ARPO-2 prototype, a solution integrating the two aspects of legal reasoning: an expert system which is able to simultaneously find the solution to a problem and to give the necessary references so that the lawyer argues the solution. The subject on which the prototype solves problems is the breach of building contracts.In this paper, we describe the process of development of an expert system for solving, justification and documentation of breach of contracts, giving details on the way how the objects that intervene in the case were defined as well as on the reasoning followed.This paper was funded in part by DGICYT, Spanish Civil Law Computerization Project: PB870-632.     

基于工学结合的网络综合布线教学改革实践

该文阐述了网络综合布线在课程体系的作用,提出了工学结合的教学设计和教学方法,最后给出教学改革产生的教学效果。     

凸显计算机专业特色的离散数学教学研究与实践

离散数学是计算机专业的一门重要基础课,对离散数学的教学研究一直是从事计算机教育工作者关注的热点。文章提出在计算机专业离散数学的教学过程中,教师应避免将该课程讲成一门数学理论课,而是对每一部分应结合计算机领域的相关实际应用背景进行阐述与引入,提高教学的针对性,从而调动学生学习积极性,促进教学质量的提高。     

Flash memory efficient LTL model checking

As the capacity and speed of flash memories in form of solid state disks grow, they are becoming a practical alternative for standard magnetic drives. Currently, most solid-state disks are based on NAND technology and much faster than magnetic disks in random reads, while in random writes they are generally not.So far, large-scale LTL model checking algorithms have been designed to employ external memory optimized for magnetic disks. We propose algorithms optimized for flash memory access. In contrast to approaches relying on the delayed detection of duplicate states, in this work, we design and exploit appropriate hash functions to re-invent immediate duplicate detection.For flash memory efficient on-the-fly LTL model checking, which aims at finding any counter-example to the specified LTL property, we study hash functions adapted to the two-level hierarchy of RAM and flash memory. For flash memory efficient off-line LTL model checking, which aims at generating a minimal counterexample and scans the entire state space at least once, we analyze the effect of outsourcing a memory-based perfect hash function from RAM to flash memory.Since the characteristics of flash memories are different to magnetic hard disks, the existing I/O complexity model is no longer sufficient. Therefore, we provide an extended model for the computation of the I/O complexity adapted to flash memories that has a better fit to the observed behavior of our algorithms.     

基于构件的软件工程及其测试、维护和实践

论述了基于构件的软件工程（ＣＢＳＥ）的基本思想。并对其带来的测试和维护上的新问题及解决方案进行了探讨。最后给出所开发的视频编码软件包的例子。     

Re-engineering of the design process for concurrent engineering

According to the requirements of concurrent engineering, three interdependency relationships (uncoupled relationship, coupled relationship and decoupled relationship) between design activities are presented in this paper. And the coupled relationship plays an important role in concurrent product design process. To represent the precedence relationships among design activities, a directed graph is used to describe the design process. And the interdependency relationship between activities is illustrated by a Design Structure Matrix which is the transpose of the accessibility matrix of the corresponding graph. Using the DSM, an algorithm of recognizing the coupled activities during the design process is presented. Moreover, an algorithm to figure out the order levels of activities during the design process is proposed. And both algorithms are illustrated with a die design example.     

并行工程在汽车车身开发与制造上的应用

本文分析了常规车身ＣＡＤ／ＣＡＭ技术所存在的弊病,提出了采用并行工程的原理进行车身开发及车身工装设计与制造的方法。重点介绍了实施车身并行工程要解决的关键性技术,诸如建立集成化的产品数据模型、ＣＡＤ／ＣＡＰＰ／ＣＡＭ集成技术、建立多功能小组、计算机技术支持等。