Web服务组合规范WS-CDL的类型化形式化模型

为了形式化地推理和验证web服务编排规范WS-CDL所描述的web服务组合,提出了一个WS-CDL规范的类型化形式化模型——typed abstract WS-CDL.在typed abstract WS-CDL中,定义了类型和会话的语法、类型判定规则和操作语义;web服务间的协作由会话来描述;利用会话的操作语义能对web服务编排的执行进行推理;利用类型判定规则能检查web服务间交换信息类型一致性并捕获由于类型不一致导致的运行时错误.特别地提出了类型假设集的外延和类型假设集相容性的概念,并定义了类型假设集的合并算法以消除类型假设冲突.在该模型基础上,还定义了从choreography到orchestration的类型化映射规则,通过这组规则,可以从一个给定的web服务choreography得到orchestration桩代码及其类型假设集,因而web服务组合能在choreography和orchestration层被验证.提出的模型被证明具有类型安全性,并且通过一个案例分析说明了所提出的模型是有助于对web服务组合进行推理和验证的.     

教育科研信息化:网络教师共同体案例研究

伴随着教育资源网络化、教育研究信息化和研究方式协同化等理念和应用的不断深入,网络教师共同体作为一种新的基于互联网的交互、协作的教育科研形式开始发挥强有力的作用.本文从教育科研信息化角度入手,选取了三个多方合作、功能较为完备的国内外教师共同体案例,对其设计方案、协作学习模式、技术支持手段、经验与挑战等方面进行了剖析.网络教师共同体逐渐成为教师专业发展、教师教育科研的基本形式,成为教育科研信息化的典型应用和充分体现.     

Polychlorinated dibenzo-p-dioxins and dibenzofurans in flue gas emissions from municipal solid waste incinerators in China

Polychlorinated dibenzo-p-dioxins and furans （PCDD/Fs） emissions in flue gas from two types of municipal solid waste incinerators （MSWIs） most commonly used in China were investigated in this study. The selected incinerators include two grate-type MSWIs： MSWI-A （350 t/d） and MSWI-B 050 t/d）, and two fluidized bed MSWIs： MSWI-C （400 t/d） and MSWI-D （400 t/d）, which are all equipped with semi-dry lime scrubber and bag filter except MSWI-D equipped with cyclone and wet scrubber （WS） as air pollutant control device （APCD）. Results indicated that the emission concentration and the international toxic equivalents （I-TEQs） of the PCDD/Fs from the stacks were in the range of 1.210-10.273 ng/Nm^3 and 0.019-0.201 ng I-TEQ/Nm^3, respectively. They were greatly lower than the emission regulation standard of PCDD/Fs in China （1.0 ng I-TEQ/Nm^3）. However, only the PCDD/Fs emission level from MSWI-C was below 0.1 ng I-TEQ/Nm^3. Although the homologue profiles were distinct, the contributions of the 2,3,7,8-subsituted congeners to the total I-TEQ were similar among all the investigated MSWIs. Two major 2,3,7,8-substituted congeners, 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDD, account for 47% and 9% （average values） of the total I-TEQ values, respectively. The correlation between PCDD/Fs levels and composition of flue gas was also discussed.     

电子商务中基于XML加密的Web服务安全的实现

随着电子商务中Web服务应用的发展,Web服务的安全问题日益突出．在对传统的Web服务安全技术分析的基础上．详细说明了作为Web服务安全技术核心的XML加密技术,并具体实现了其在Web服务安全中的应用．     

开放教育法律实践教学的形式

实践教学是人才培养模式改革和开放教育试点教学工作的一个重要内容.案例教学、判例教学、法律诊所、庭审旁听、模拟法庭、法律咨询、社会调查、专业实习、专家授课等法律实践教学的主要形式,是法律专业学生理论联系实际,提高法律素质的重要途径.     

西部人才队伍建设的现状及对策

西部人才队伍规模偏小 ,总量不足 ;整体素质不高 ,创新能力不强 ;地区、行业之间分布不够合理 ;结构不合理 ,高层次人才紧缺 ;人才管理体制和管理模式不能完全适应社会主义市场经济体制要求 ;科技教育比较薄弱 ,人才建设基础不够雄厚。西部人才队伍建设必须坚持培养、吸引和使用三者一起抓 ,以培养和使用好本地人才为主 ,兼顾吸引国内外高层次、高素质和急需人才为辅     

MEASUREMENT OF THE DIELECTRIC PROPERTIES OF BIOLOGICAL TISSUE

An open-ended coaxial line reflection method especially suitable for meas-uring the dielectric properties of biological tissue in vivo is described.This method offersthe advantage of not requiring any special preparation of the samples to be measured but aclose contact with the open end of a coaxial line.It is,therefore,very convenient to acquirea large number of measurement data in broad band rapidly.The method may also be usedto measure the properties of other substances.The measuring system consists of a networkanalyzer controlled by a microcomputer and calibrated by using ANA procedure to elimi-hate the influnce of error network introduced by the adapter,some connectors,etc.In or-der to reach higher accuracy,the iterative method is used to determine the parameters ofthe equivalent circuit.Measurements of permeativities of some living tissues have been per-formed in the frequency band of 0.5-2GHz.Compared with the results known in somepapers,the validity of this method has been confirmed.The difference in dielectric proper-ties between living and dead tissues,and the tissue permeativites(ε)versus frequency andduration of measurement after death have also been measured.     

Visualization of Wormlike Micelle Fluid Flow in a Mixing Tank

In this study,particle image velocimetry was applied to investigate flow fields of wormlike micelle(WLM) fluids in a mixing tank equipped with a four-blade,down-pumping,pitched blade turbine. First,the rheology of WLM fluids was investigated,and the Carreau model was utilized to describe their apparent viscosity. Then,the effects of the rotation speeds and rheological properties on the flow fields were studied using different WLM fluids at different rotation speeds. The results revealed that with increasing Reynolds number,the discharge angle decreases and the carven size increases. Furthermore,elastic effects of WLM fluids lead to a more curved flow and a smaller carven.     

论幽默话语的结构和语用功能

幽默话语是由语言的各种要素的变异使用而产生的一种具有审美情趣的言语行为。人类物质文明和精神文明发展到今天,幽默在人们的现实生活、艺术世界以至整个精神领域的地位越来越重要。本文从实例分析入手,论述了幽默话语的表层和深层结构以及它的审美和交际功能     

外源催产素对恒河猴卵巢黄体的影响(英文)

本文研究了外源催产素对弥猴的月经周期和血清孕酮含量的影响，结果发现皮下注射催产素可以缩短黄体期，但对血清孕酮含量无影响．为此本研究认为只有在有效产剂量长期刺激下才对黄体产生影响，且催产素对黄体的作用有一敏感期．对于上述推论及催产素是否直接作用于黄体或通过其它途径调节黄体功能，我们在局部试验及其它试验中加以证实．