新一代数字电视传输标准DMB-T的关键技术

本文描述了地面数字电视广播（Digital Televison Terrestrial Broadcasting ,DTTB)的要求和地面数字电视广播的信道特点，在介绍国外现有的DTTB传输标准的基础上说明了清华大学数字电视传输技术研发中心提出的DMB－T（Terrrestrial Digital Multimedia /Televison Broadcasting)标准。通过与现有标准在调制、同步、信道估计等方面的比较证明,DMB-T具有优越的性能。     

衍生交易、风险管理与公司治理——中航油事件反思

本文以中航油巨亏事件为例，分析了跨国企业的衍生交易、风险管理与公司治理之间的关系。研究发现，中航油巨亏事件的根本动囚是对衍生金融工具认识不足，以致没能很好遵循国际会计准则惯例并导致投资风险的增加。同时，中航油自身在企业风险管理上的弱化，又逐渐滋生了公司治理的内生性问题，即内控机制和监控机制的缺乏。因此，对企业风险的有效管理和公司治理的有效监督是解决当前跨国企业投资风险的最佳办法。     

Wages distribution in Poland: The roles of privatization and international trade, 1992-96

This paper reports an investigation into the changes in the wage distribution in Poland in the first half of the 1990s. We concentrate on the effects of privatization and international trade. We show that the tendency towards increased dispersion in wages halted between 1992 and 1996, despite a rapid expansion in private-sector work. We also show that, during the same period, private-sector workers typically earned less than their state-sector counterparts on an hourly basis, and this gap widened. However, if one controls for experience, tenure and size of workplace, then there existed a small positive private-sector premium. On the effects of international trade, we find suggestive circumstantial evidence that the increase in trade with Western Europe raised wages and employment in manufacturing.     

驱动与阻碍:网络位置影响知识转移的系统动力学研究

基于网络位置的“双刃剑”特性，从驱动机制和阻碍机制着手构建网络位置影响知识转移的系统动力学模型，并进行仿真和灵敏度分析。结果显示：知识转移受到网络位置驱动与阻碍的双重影响;当企业占据较高的网络中心度与较少的网络结构洞时，协同效应最显著，知识转移量最大。该研究揭示了网络位置对知识转移的影响机制，也可为企业选择合适的网络占位提供借鉴与依据。     

An investigation of AAA diamond rating changes on hotel performance

Despite previous attempts to link hotel rating systems to performance, no prior study has examined the effects of changes in Diamond ratings. Considering the variability in Diamond ratings, and the fact that hotels may gain or lose a Diamond over time, it is important for hotel properties to assess such outcomes on key performance indicators (KPIs). Hence, this study examines the influence of Diamond rating changes on hotels’ KPIs (i.e., occupancy rate, average daily rate, and revenue per available room) and competitive set indexes, which allow to benchmark a property’s performance against a designated competitive set. Results suggest that in both the short and long-terms, significant differences in KPIs and indexes exist between properties which benefited from an increase in Diamond rating, versus those which suffered from a drop in Diamond rating. Furthermore, despite such improved performances over time, improvements in hotels’ KPIs and indexes tended to diminish over time. The current findings yield important contributions to the literature regarding the effects of hotel rating changes on KPIs and indexes and provide valuable insights to hotel owners and operators.     

关键研发者自我中心网络变化对企业创新绩效的影响:以整体网络为中介变量

关键研发者作为组织创新的重要参与者,对创新绩效具有显著影响,但其影响机制不明确。以整体网为中介变量,利用36家通讯制造企业专利数据,分两个步骤探究关键研发者对创新绩效的影响机制。第一步,探索关键研发者的个人网络特征、网络规模及网络密度变化对整体合作网络和知识网络中介中心势的影响;第二步,研究整体网络的中介中心势变化(正向和负向)与创新绩效的关系。结果表明:在合作网络中,关键研发者自我中心网络规模变化幅度增大会引起整体合作网络中介中心势变化幅度增大;关键研发者引起的合作网络中介中心势变小会使企业创新绩效显著降低;在知识网络中,关键研发者自我中心网络规模与网络密度变化幅度增加均会使整体知识网络中介中心势变化幅度显著增大。由关键研发者引起的知识网络中介中心势变小会使企业创新绩效显著提升。     

Analyzing the effect of aviation infrastructure over aviation fuel consumption reduction

The purpose of this paper is to examine the effect of various aviation infrastructure dimensions over aviation fuel consumption reduction (AFCR) performance. This study is an effort that considers the role of dimensions collectively from all aspects belonging to aviation infrastructure. The relevance of dimensions and constructs for hypothesis development are based on extensive literature review. Exploratory factor analysis (EFA) and Confirmatory Factor Analysis (CFA) were performed in the consecutive purification processes. Also, hypothesis testing was conducted using Structural Equation Modeling (SEM). A customized questionnaire was developed for collecting data from both kinds of respondents: Aviation industry experts and academic experts. Out of 382 approaches through mail survey, a total of 194 valid responses were collected. Analysis of the results shows the positive and significant impact of various factors such as: airport design, airspace management and air traffic control over the aviation fuel consumption reduction. Maximum importance is adjudged on air traffic control (ATC) and airspace route flexibility. The results of this study will encourage airlines and airport development authorities to increase their insight over aviation infrastructure, also to perform deeper analysis and find out precise values for real life implications.     

Using Statistics and Statistical Thinking to Improve Organisational Performance

A systematic approach to measuring organisational performance is fundamental to the pursuit of business excellence. As such, the area of organisational performance measurement, and its use of data and analysis to inform business decisions, affords statisticians a potentially high value-adding opportunity. To be effective in this area, statisticians need to appreciate the differing requirements for statistical information in various management zones of an enterprise.
This paper describes a strategy that seeks to link measurement to all facets of organisational performance, particularly to desired business outcomes, and also to mesh measurement with process improvement in a natural way. The use of statistics and statistical thinking is then discussed in this context, with particular focus on the opportunity for statisticians to have a key role at the top decision-making level of the organisation. We argue that the role requires skills in both advanced technical statistical modelling and analysis, and in statistical thinking. It also requires a preparedness to form an appreciation of the business and management imperatives faced by the leaders of an enterprise, and a willingness to work from this basis.     

空地数据链路研究

本文介绍了一种作用距离远、信息量大且实时性要求高的数据传输链路方案，通过同步卫星中继，预计能达到2Mbps的数据传输率，误码率为10^-6。     

高校大部制改革范围经济的理论分析

范围经济是评价高等学校生产效率的重要工具。高校大部制改革是现今一大热点问题,从范围经济这一角度看,高校大部制改革有利于高等教育教学、科研、社会服务三大功能的资源共享,有利于本科生、硕士生、博士生培养的资源共享,有利于专业跨度整合。但在大部制改革的过程中,需要用有机整合代替机械结合,不同学科合并大部需要具体论证、分别对待,并且应充分论证大部制合并的范围。