城域网MAC层协议的优先级结构及性能

主要研究城域网MAC层标准“IEEE 802.6 DQDB”协议的优先故排队性能;提出了一种DQDB协议的优先级实现方案—β分级结构。通过本文给出的文件传输性能分析以及计算机模拟证明,这种新的优先级结构可取得比DQDB现有结构更好的性能,而且易于实现。     

跨文化沟通与国际经济

搞好跨文化沟通是国际经济活动成功的重要条件.本文以西欧、美国、阿拉伯国家和日本为对象探讨其文化差异和沟通的途径.     

跨文化交际中的非语言语用失误

非语言交际是交际的一种重要形式。跨文化非语言交际语用失误包括体态语、副语言、客体语和环境语的语用失误。这些失误主要是由于交际双方不同的文化背景和社会环境,以及对认知语境的失误判断引起的。     

Help or hype: Symbolic or behavioral communication during Hurricane Katrina

Public relations professionals increasingly rely on the World Wide Web to communicate with their publics on a variety of issues, including the corporate social responsibility (CSR) efforts the organization has undertaken. In the aftermath of Hurricane Katrina, there is an opportunity to discover how the Best 100 Global Brands used their corporate websites and the power of their brand equity to help the victims of the disaster, as well as to communicate their own CSR efforts. Results show that 51% of these Top 100 firms had messages on their homepages about Hurricane Katrina, and 86% of those firms made donations totaling $105,000,000. The remaining 14% of firms exhibited symbolic communication only, with links to philanthropic organizations aiding rescue efforts.     

液相色谱串联质谱检测鳗鱼中四种氟喹诺酮残留

建立了液相色谱/串联质谱法测定鳗鱼中恩诺沙星,环丙沙星,诺氟沙星,氧氟沙星的方法。对分离和检测这四种兽药残留的液相色谱条件、质谱条件、样品前处理方法等作了详细的研究。用乙腈萃取样品中的残留物,在氮气保护下将萃取液浓缩干,加流动相1.0mL溶解残渣,正己烷液液萃取,弃上层液,下层溶液用作液相色谱分析荧光检测或质谱检测。在鳗鱼样品中添加四种残留物,添加浓度分别为0.01,0.050和0.100mg/kg,平均回收率(n=6)在70￣84.3%之间,相对标准偏差为3.0%～6.3%。     

论限制网络传播权应遵循的原则

对著作权人行使网络传播权进行的合理限制是网络传播权产生、网络事业发展的必然要求,限制网络传播权应遵循效率与公平平衡统一的原则、现代化原则、国际化和本土化相结合原则、诚实信用原则和公序良俗原则。     

史料引用致误原因分析

史料是史学研究的基础.但自古以来,由于种种原因,错误的或者事实模糊不清的史料很多,如果不作必要的考证鉴别,很难获得科学的研究成果.造成史料引用致误的原因是多方面的,归结起来主要有:(1)史料本身无误,由于没有正确理解原意或者标点不正确而致误;(2)史料本身无误,由于引用者推断不确而致误;(3)史料内容比较含蓄,由于引用者缺乏深入辨析而致误;(4)没有直接引用原书而致误;(5)因版本不善而造成史料的错误或脱漏;(6)史料本身就有错误.     

Statistics for weighing benefits and harms in a proposed genetic substudy of a randomized cancer prevention trial

Summary.  When evaluating potential interventions for cancer prevention, it is necessary to compare benefits and harms. With new study designs, new statistical approaches may be needed to facilitate this comparison. A case in point arose in a proposed genetic substudy of a randomized trial of tamoxifen versus placebo in asymptomatic women who were at high risk for breast cancer. Although the randomized trial showed that tamoxifen substantially reduced the risk of breast cancer, the harms from tamoxifen were serious and some were life threaten-ing. In hopes of finding a subset of women with inherited risk genes who derive greater bene-fits from tamoxifen, we proposed a nested case–control study to test some trial subjects for various genes and new statistical methods to extrapolate benefits and harms to the general population. An important design question is whether or not the study should target common low penetrance genes. Our calculations show that useful results are only likely with rare high penetrance genes.     

汉口租界的报刊与传播控制

近代汉口新闻事业之发端与繁荣,与租界及租界特殊的传播环境有密切关系。开埠以来,外侨与国人在汉口的五国租界里创办了近百种报刊。租界内的新闻传播受到多方面控制:汉口租界当局的基本章程中有关于新闻传播管理的条例;满清与北洋政府从多方面对租界内的报刊进行钳制;军阀势力与帝国主义列强亦常插手干涉。与上海租界相较,汉口租界的媒介与传播环境仍有自己的特色。     

民族院校新闻传播学科发展的路径选择

民族院校应该是以全面服务于非主流族群作为自身的基本定位，民族院校的新闻传播学科要在准确理解这一定位的基础上确立自身的发展路径，以鲜明的特色建构来强化自身的学科核心竞争力。