资源型城镇环境生态建设

我国资源型城镇面临严峻的环境问题和生态问题,许多小城镇生态绿化体系尚未建立。文章通过对国内外资源型城镇环境和绿化现状以及资源型城镇的分析,结合政府的生态管理职能和景观规划理论,提出环境生态建设的建议与措施,为实现资源型城镇的可持续发展奠定一定的理论基础。     

NURBS曲线C~1连续参数优化算法

曲线的参数特性直接决定基于自由曲线的路径规划、运动控制等算法的质量.为了生成满足C1连续的近似弧长参数化,提出一种基于分段三次重新参数化的参数优化算法.首先利用Simpson方法离散积分能量,然后使用极值求解法求得初始解,最后通过LM(Levenberg-Marquardt)优化算法计算出曲线的最优参数表示.与C1连续的分段有理重新参数化方法相比,该算法能够在分段数量很少的情况下达到局部最优.最后通过实例说明了文中算法的有效性.     

Reaction-formed W2B5/C composites with high performance

Highly densified W₂B₅/C composites with W₂B₅ content from 30 to 70 vol% were fabricated by reaction hot pressing of the powder mixture of B₄C, WC and carbon black. The reaction products were identified by XRD analysis to consist of only W₂B₅ and carbon, regardless of carbon content. The reaction formed composites have excellent mechanical properties (the maximum flexural strength and fracture toughness of 786 MPa and 8.9 MPa m^1/2 respectively), electrical conductivity (the highest electrical conductivity of 1.64 × 10⁶ Ω⁻¹ m⁻¹), and resistance to both wear and oxidation because of the presence of the plate-like W₂B₅ grains. In this paper, the preparation, microstructure and properties of this new composite are investigated, and the strengthening, toughening, conduction mechanisms are discussed.     

浅谈海南影视动画产业发展中的政府作为

影视动画产业是当今社会的朝阳产业,是传统经济发展和延伸的一种新方式,政府对影视动画产业十分重视.而影视文化产业具有浓厚文化色彩和广阔的自由发展空间,有利于影视动画的进一步发展与建设.影视动画产业发展对象可以是影视基地,也可以是影视剧本,产业发展对象丰富,所以此产业的发展前景非常明朗,并且还具有高度的研究价值.     

关联规则算法在法规备案审查工作中的应用

根据宪法和有关法律规定,全国人大常委会监督宪法和法律实施可以采取多种形式,法规备案审查正是其中一个重要的监督方式.我国的法规备案审查制度包含着违宪性审查和违法性审查两个层次的内容,其最高层次的法律渊源是宪法.现行宪法规定,全国人大常委会有权撤销国务院制定的同宪法、法律相抵触的行政法规、决定和命令,撤销省、自治区、直辖市国家权力机关制定的同宪法、法律和行政法规相抵触的地方性法规和决议.法规审查是一个复杂的过程,对具体负责审查工作的人员有极高的法律法规知识要求.因此,提高法规审查的科学性、客观性和准确性,是当前法规审查工作重要的课题.本文结合当前法规备案审查的实际,提出了法规关联分析评价指标体系,应用于法规审查工作中,并在此基础上设计并实现了法规备案审查系统.     

基于Oracle数据库的双机集群系统的设计与实现

通过简述集群技术的应用与双机容错技术的基本原理与优势,依据实例研究在在双机集群环境下实现Oracle并行服务的方法,实现了软、硬件上的容错以及动态负载均衡等高可用功能.     

常用数据加密技术的对比研究

如今的世界已经是一个信息化和数字化交织的庞大体系,人们对数据安全和保密的重要性认识不断提高,为确保数据的安全多种加密技术被广泛使用。然而数据的非法复制,解密和盗版问题日益严重,数据加密技术依旧是很重要的环节,本文仅对目前常用的加密算法加以比较研究提出较好的加密方法。     

l-薄荷醇的合成工艺研究

以d-香茅醛为原料,合成了l-薄荷醇。考察了反应温度、反应时间、催化剂用量、催化剂位阻对中间体异胡薄荷醇(Ⅵ)收率的影响。合成中间体Ⅵ的最佳工艺条件:甲苯为溶剂,d-香茅醛为起始原料,以铝原子为中心,三苯基苯酚为配体的催化剂用量为1%(摩尔分数),反应温度0℃以下,反应时间5 h。中间产物Ⅵ经加氢还原得到l-薄荷醇,总收率77%,GC纯度99%以上,反应的优点是异构产物少,选择性高,收率稳定。     

核为︱x-s︱~(-1)ln︱x-s︱的强奇异积分的数值计算法

讨论了核为︱x-s︱~(-1)ln︱x-s︱的一种强奇异积分∫baln︱x-s︱/︱x-s︱f(xdx),给出了它的Hadamard有限部分积分的定义,并利用Lagrange线性插值构造了函数这类强奇异积分的数值算法,最后分析和讨论了算法的误差估计。     

Modeling the Value-Based Software Process with Object-Petri-Nets

Commercial organizations increasingly need software processes sensitive to busi- ness value, quick to apply, supportive of multi-stakeholder collaboration, and capable of early analysis for subprocess consistency and compatibility. This paper and a companion paper \Applying Value-Based Software Process: An ERP Example" present our experience in ap- plying a lightweight synthesis of a Value-Based Software Quality Achievement (VBSQA) process and an Object-Petri-Net (OPN) based process model to achieve a stakeholder win- win outcome for software quality achievement in an ERP software project in China. We attempt to answer such questions as (1) whether it is possible to model various project stakeholder perspectives using formal process modeling languages in a real-world project? (2) how to make stakeholders synchronize and stabilize their value propositions, activities and commitments as needed. The companion paper presents the VBSQA process and its application to the ERP project; this paper presents the OPN-based process modeling and its application. The application results of OPN process modeling conˉrmed that (1) the OPN- based process model provided project managers with a synchronization and stabilization framework for process activities, success-critical stakeholders and their value propositions; (2) process visualization and simulation tools signiˉcantly increased management visibility and controllability for the success of the software project.