Inspection of an unreliable flexible manufacturing system: with repairable parts and non-negligible inspection times

The purpose of this paper is to address the problem of quality control and repair in an FMS which is described by an open queuing network. We consider two cases: first, all detected defective parts are directed to a special repair facility; second, a defective part is repaired within the machine group where it is detected. Using numerical analyses, we provide some managerial insights regarding the role, position, and distribution of the inspection effort in an FMS, and draw some inferences regarding the design of such FMS when both quality and quantity issues in the FMS are considered.     

The Gaussian Mixture Dynamic Conditional Correlation Model: Parameter Estimation,Value at Risk Calculation,and Portfolio Selection

A multivariate generalized autoregressive conditional heteroscedasticity model with dynamic conditional correlations is proposed, in which the individual conditional volatilities follow exponential generalized autoregressive conditional heteroscedasticity models and the standardized innovations follow a mixture of Gaussian distributions. Inference on the model parameters and prediction of future volatilities are addressed by both maximum likelihood and Bayesian estimation methods. Estimation of the Value at Risk of a given portfolio and selection of optimal portfolios under the proposed specification are addressed. The good performance of the proposed methodology is illustrated via Monte Carlo experiments and the analysis of the daily closing prices of the Dow Jones and NASDAQ indexes.     

More nonconcavities in information processing functions

The productivity of (human) information processing as an economic activity is a question that is raising some interest. Using Marschak's evaluation framework, Radner and Stiglitz have shown that, under certain conditions, the production function of this activity has increasing marginal returns in its initial stage. This paper shows that, under slightly different conditions, this information processing function has repeated convexities with ongoing processing activity. Even for smooth changes in the signals' likelihoods, the function is only piecewise smooth with non-differentiable convexities at points of conditional changes of action. For linear likelihood functions the processing value proves to be piecewise linear with convexities at these levels. This revised version was published online in June 2006 with corrections to the Cover Date.     

Communicative competence and the facilitating and perturbing factors in the socialisation of immigrant students

This work analyses the communicative competence and the factors that facilitate and perturb the socialisation of immigrant students in primary education. It provides greater knowledge concerning the relationship between the immigrant student's social and linguistic competence. It also analyses the presence of difficulties in the different language components (morphology, syntax, semantics and pragmatics). The sample is made up of a total of 326 immigrant students between 6 and 12 years of age, attending 10 different schools. The study demonstrates that immigrant students possess a low level of linguistic dominion. All the linguistic components analysed are affected, although greater difficulties are evident in morphology and syntax than in semantics and pragmatics. The relationship between linguistic competence and the factors that facilitate and perturb socialisation is underlined. This work concludes that there is a significant relation between semantics and pragmatics and several socialisation factors (leadership, aggressiveness–stubbornness and anxiety–shyness). The educational centres should be aware of the complicated learning process that immigrant students have to go through.     

现代性效果与地域文化差异——转型期中国社会价值观的分化与整合

当下中国社会所经历的结构转型与体制调整不仅在客观环境上改变着人们的日常生活方式,更在主观内心世界里影响着人们对于自身所处生活状态的认知与判断,一方面,由于工业社会发展过程中“现代性”的主题效果在中国社会日益扩大,另一方面,传统文化的地域性差异与多样性同时在不同层次上作用于中国社会的日常运作模式中,这一社会变迁中两种力量...     

大学生群体对社会工作职业声望评价探析——以四川农业大学本科生为例

为了解社会工作目前的职业声望,本文通过问卷调查了作为社会先进群体的大学生对社工的职业声望评价。调查结果显示,大学生自身所持有的价值观、择业要求会影响对职业的评价,对社工本身的了解程度也是影响因素之一。笔者因此建议通过大力加强社工价值教育,扩大舆论宣传和提高社工福利等措施来提高社工的职业声望。     

审美：语文教育本质的回归

本文认为语文审美教育是建立在语文教育发展的必然性、语文的本质规定性以及人的发展和内在需要基础之上的。其内涵是主体在一切言语实践中，运用强有力的言语材料，直接对个体或类的生命存在本身进行塑造、规范和引导，以提高生命质量的一种自觉的教育活动。     

重新审视事实与价值的区分

自从元伦理学以来,事实与价值的区分被认为是价值概念的基础。以“是”为述词的判断形式和以“应当”为述词的判断形式是根本不同的,前者是事实判断,后者是价值判断。当代哲学的这一认识来源于休谟。但休谟是在一种道德文化转换背景下意识到这种区分的,当现代哲学家把它看成是价值研究的基本前提时,就取消了价值存在的本体,从而把价值看成是对主体自身态度的表达。新自然主义提出区分自然事实与社会事实,认为价值与社会事实内在相关,我们认为,新自然主义的这一认识揭示了价值的源泉。     

新课程理念下的英语教学改革浅谈

《英语课程标准》强调课程应从学生的学习兴趣、生活经验和认知水平出发 ,倡导体验、实践、参与、合作与交流的学习方式和任务型教学途径 ,发展学生的综合语言运用能力。     

金融风险度量VaR与CVaR方法的比较研究及应用

风险价值(VaR)是近年来受到国际金融界的广泛支持和认可的一种度量金融风险的工具。文章指出了风险价值(VaR)模型两个重大的缺陷,并对它和条件风险价值(CVaR)金融风险度量模型进行了详细的介绍和对比分析,给出了它们的共同点和CVaR在投资组合应用中的优势,结合中国金融市场的实际情况,指出CvaR在中国金融市场中应用应注意的问题,对其应用前景提出了新的思路。