中国有线电视产业改革:竞争与规制

在中国广电系统积极推进有线电视产业化过程中,重构有线电视产业组织结构、促进有效竞争的同时,建立和完善其政府规制体系至关重要。本文在研判有线电视产业属性并分析有线电视产业现行管理机制存在问题的基础上,探讨对于进入产业化改造初期的有线电视产业,借鉴波特竞争模型,从微观主体重构、替代品竞争等方面提升有线电视产业的可竞争性。同时,提出构建有线电视产业规制体系的战略选择:设置专门的规制机构、严格进入规制、实施非对称规制,改进频道资源、节目内容的分类规制,加强规制立法,以提高对有线电视产业的规制质量,促进有线电视产业的良性发展。     

论农村、农业、农民的"四性与四化" --关于"三农"问题研究的理论构架

“把握农业的产业属性和市场化趋势,把握农村的社会属性和现代化进程;把握农民的主体属性和国民化要求;把握‘三农’的基础属性和国际化走向”即“三农”问题研究中的“四性与四化”的理论模式,这是在实际调查和对历史与现实情况的社会分析基础上提出的认识框架,它推进了“三农”理论的创新。     

双权值最短路径问题的一种解决算法

物流配送方案中,费用、时间是客户最关心的两个问题。物流企业需要基于这两个客户所关心的问题,提出一套低成本的物流配送方案。本文探求使用费用、时间双权值有向图最短路径问题,解决这种配送方案,并进行算法的时间复杂度分析。     

D-S证据理论中冲突证据的合成方法

针对高度冲突证据的合成问题,分析了D-S合成方法及其改进方法的不足,提出了一种新的改进方法。新方法仍利用D-S合成公式,但针对该公式要求参与合成的各证据需具有相同重要程度的要求,考虑到融合系统中各证据的重要程度可能不同,直接利用公式合成可能得到与实际相悖的结论,因而引入证据权的概念,给出了证据权的具体算法,通过证据权对已有的基本可信度分配函数进行修正得到了重要性相同的新的证据的基本可信度分配模型。最后通过算例比较表明新方法的合成结果更为理想。     

平淡出奇巧简明蕴繁复--鲁迅《风波》重量人名巧用

鲁迅<风波>中七斤一家的重量人名是其小说中常用的数字人名之一种.作者结合秤的度量标准的变化和人的生理规律,经过仔细推算确定、使用的重量人名,在表面的民俗现象之下,暗示出辛亥革命时期社会经济凋敝,民众饱受通货膨胀之苦的生存现实.这与小说反映的民众的精神意识相辅相成,完整勾勒了辛亥革命时期的社会风貌,从而在经济状况这一层面表达了鲁迅对社会变革的深重忧虑.     

A bayesian test for a two-way contingency table using independence priors

One method of testing for independence in a two-way table is based on the Bayes factor, the ratio of the likelihoods under the independence hypothesis H and the alternative hypothesis H. The main difficulty in this approach is the specification of prior distributions on the composite hypotheses H and H. A new Bayesian test statistic is constructed by using a prior distribution on H that is concentrated about the “independence surface” H. Approximations are proposed which simplify the computation of the test statistic. The values of the Bayes factor are compared with values of statistics proposed by Gunel and Dickey (1974), Good and Crook (1987), and Spiegelhalter and Smith (1982) for a number of two-way tables. This investigation suggests a strong relationship between the new statistic and the p-value.     

古代宪法概念变迁之中西比较

古代宪法是一个容易被忽视的研究领域,然而古代宪法又是一个现代宪法的宝藏发源地。古代宪法概念变迁过程大致可从两个角度来看:首先,从纵向上,其经历了历史渐进的变化;其次,从横向上,还存在一个无法忽视的东西方比较,其中表现最明显的应是中西比较。基于时代的不同和价值观念的差异,古代东西方宪法概念被赋予了不同的内涵和意义。本文正是从这种纵横两方面的比较,追根溯源,来寻找东西方古代宪法概念的内在联系和差异,从而为解读现代宪法的正式含义提供可靠的参考。     

Evaluating Weight of Evidence in the Mystery of Balkan Endemic Nephropathy

Balkan endemic nephropathy (BEN) is a chronic, progressive wasting disease of the kidneys, endemic in certain rural regions of the Balkan nations Croatia, Serbia, Bulgaria, and Romania. It is irreversible and ultimately fatal. Though this disease was first described in the 1950s, its causes have been a mystery and a source of much academic and clinical contention. Possible etiologic agents that have been explored include exposure to metals and metalloids, viruses and bacteria, and the dietary toxins aristolochic acid (AA) and ochratoxin A (OTA). AA is a toxin produced by weeds of the genus Aristolochia, common in Balkan wheat fields. Aristolochia seeds may intermingle with harvested grains and thus inadvertently enter human diets. OTA is a mycotoxin (fungal toxin) common in many foods, including cereal grains. In this study, we analyzed the weight of evidence for each of the suspected causes of BEN using the Bradford Hill criteria (BHC): nine conditions that determine weight of evidence for a causal relationship between an agent and a disease. Each agent postulated to cause BEN was evaluated using the nine criteria, and for each criterion was given a rating based on the strength of the association between exposure to the substance and BEN. From the overall available scientific evidence for each of these suspected risk factors, AA is the agent with the greatest weight of evidence in causing BEN. We describe other methods for testing causality from epidemiological studies, which support this conclusion of AA causing BEN.     

关于带权Hardy不等式

本文得到了Hardy算子Tf(x)=integral from o to x f(t)dt从空间L~p(R_+,vdx)到L~q(R_+,Udx)有界的权函数对(u,v)的特征,其中1≤q相似文献   

一类拟微分算子的强Grding不等式

研究由S?类象征所规定的拟微分算子的Garding不等式,利用一对新的权函数Ψ,Ψ,导出了由S?(0相似文献