人口稀疏地区的环境保护问题

目前,环境保护成为全球亟待解决的问题.由于越来越多的地区参与到经济活动中,因而环境保护涉及包括人口稀疏地区在内的各个地区.在多数情况下,人为因素给环境带来了许多负面的影响. 环境问题不仅与整个国家相关,也与各个地区相关,包括俄罗斯的沃洛格达地区.     

Modelling human immunodeficiency virus ribonucleic acid levels with finite mixtures for censored longitudinal data

The measurement of human immunodeficiency virus ribonucleic acid levels over time leads to censored longitudinal data. Suitable models for dynamic modelling of these levels need to take this data characteristic into account. If groups of patients with different developments of the levels over time are suspected the model class of finite mixtures of mixed effects models with censored data is required. We describe the model specification and derive the estimation with a suitable expectation-maximization algorithm. We propose a convenient implementation using closed form formulae for the expected mean and variance of the truncated multivariate distribution. Only efficient evaluation of the cumulative multivariate normal distribution function is required. Model selection as well as methods for inference are discussed. The application is demonstrated on the clinical trial ACTG 315 data.     

区域经济现代化问题

20年前,俄罗斯向市场型社会经济生活组织的转型是复杂而充满矛盾的,原因之一是市场改革的战略和决策,原因之二是世界经济快速全球化背景下危机的表现方式. 在俄罗斯联邦第一任总统叶利钦执政时期,俄罗斯创建了大型民营企业、商业环境和市场基础设施.新社会秩序的基本步骤是建立在"休克疗法"基础之上,国家工业产值减少一半,固定资产投资减少五倍,就业率急剧下降,人民生活水平降低,国家的完整性也受到威胁.     

Can We Perceive Near Miss? An Empirical Study

Near misses are a special kind of reinforcement which increases one’s desire to play. The aim of this paper is to examine the perception of near misses in normal population. We used a slot machine simulation running on a PC, where participants had to play four rounds with different near miss ratios (0, 15, 30 and 45%). Our sample consisted of 159 individuals with mean age of 22.8 and with no or little gambling experience. For data analysis we used chi-squared goodness-of-fit test and exact binomial test. Despite the fact, that there was a notable effect of near misses results showed that the subjects could not perceive trials of them.     

历史的创新教学

教学创新是现代教学发展的必然趋势,运用新的教学手段和理念,培养学生的创新能力,是初中历史教学创新的客观要求.为了适应历史教学新形势的需要,必须遵照新课标下的历史教学要求,创新历史教学原则、教学理念、教学手段等等.     

拉动消费的意义

尽管过去十年里，中国的实际工资水平上涨了12．5％，但是消费在经济中所占的比例却在下降，因此，评论员怀疑，企业家面临的是国内外需求及生产能力同时萎缩的局面。