飞机排故专家系统的EASERVER三层结构设计

针对航空公司维修部门及其维护信息库多而分散的特点,提出了一种基于EASERVER应用服务器的C/A/S三层软件结构解决方案,该方案作为飞机排故专家系统,优化了专家系统的软件结构,避免了硬件升级,并节省了费用。采用不可视对象和DATAWINDOW结合处理技术,满足了专家系统对大量数据处理和数据共享的要求。     

论高等教育系统的分化与重组

伴随着高等教育规模的不断扩大,高等教育系统趋同问题已引起各国学者与政府的高度重视。为了使高等教育更好地适应社会经济发展的需要,各国纷纷采取措施以促进高等教育系统的分化与重组。高等教育系统趋同有其内在必然性,高等教育系统分化与重组的关键在于,通过规划与竞争促进高等教育机构类型、质量标准与职能的多样化。     

形式语言中的上下文无关和上下文相关

形式语言与自动机理论已成为计算机科学的理论基础；对于程序设计语言的说明和分析尤其重要。文中介绍了形式语言与自动机理论中的基本原理，给出了上下文无关文法、上下文相关文法及其相应语言的定义，讨论了它们之间的关系。     

高素质婴幼儿教师教育培养的实践研究

教师教育已经成为影响到幼儿教育发展的重要因素。如何培养高素质婴幼儿教师教育已经引起人们的高度重视,因此对其培养目标、课程设置、教育内容、教学方法等方面急需进行深入细致的探讨和研究,为探索我国师范教育调整下本科层次幼儿教师的培养提供一定的研究基础。     

Further theoretical results and a comparison between two methods for approximating eigenvalues of perturbed covariance matrices

Covariance matrices, or in general matrices of sums of squares and cross-products, are used as input in many multivariate analyses techniques. The eigenvalues of these matrices play an important role in the statistical analysis of data including estimation and hypotheses testing. It has been recognized that one or few observations can exert an undue influence on the eigenvalues of a covariance matrix. The relationship between the eigenvalues of the covariance matrix computed from all data and the eigenvalues of the perturbed covariance matrix (a covariance matrix computed after a small subset of the observations has been deleted) cannot in general be written in closed-form. Two methods for approximating the eigenvalues of a perturbed covariance matrix have been suggested by Hadi (1988) and Wang and Nyquist (1991) for the case of a perturbation by a single observation. In this paper we improve on these two methods and give some additional theoretical results that may give further insight into the problem. We also compare the two improved approximations in terms of their accuracies.     

“新村级债务”：形成机制与社会后果

不同于税费时期的“老村级债务”,“新村级债务”是在取消农业税以后,国家公共财政资源以项目制为主要形式向农村输送的背景下产生的村级债务,项目制是新村级债务产生的基础。新村级债务具有普遍性、差异性、私人性、隐蔽性等特点。村庄发展导向、村干部经营项目是村级债务产生的内在原因,项目的资金配套制度和地方政府的自利逻辑是村级债务形成的外因。新村级债务对乡村社会的影响是全面的,造成了村级权力固化、村庄主体性丧失、乡村关系扭曲以及村庄间分化加剧等严重后果。随着新村级债务的不断膨胀,容易造成新的债务危机,应当高度警惕。     

More on local influence in pllincipal components analysis

Local influence on the eigenvalues of sample covariance matrices in

principal components analysis is examined for a reasonable modification of Shi's (1997) perturbation scheme, The modification is suggested for samples from populations with both unknown mean vector and covariance matrix. While Shi's detection indexes (1997) consist of only quadratic terms, the modified perturbation scheme leads to detection indexes constituted by both linear and quadratic terms associated with centralized observations. These linear and quadratic terms reflect local influences on the first two sample moments. Examples are investigated based on the two detection indexes.     

针对影像处理的快速二维离散余弦转换算法(英文)

由于离散余弦转换在影像处理领域之重要性与日俱增,且消耗许多处理器运算时间,所以众多快速二维离散余弦转换算法不断被发表。该文提出一个应用于JPEG及MPEG图像处理的快速二维8×8离散余弦转换算法,该算法主要运用基本的累加及移位运算,快速评估8×8影像区块的复杂程度,可调整离散余弦转换参数的计算数量。该算法只需花费少量硬件成本,如比较器、加法器、移位器,便可有效降低离散余弦转换运算时间,且在模拟结果显示所提出的算法与传统及整数离散余弦转换相比,可达到较快的运算速度,且在量化系数较大的情况下,可得到更好效果。     

Inference on proportional hazard rate model parameter under Type-I progressively hybrid censoring scheme

ABSTRACT

In this paper, under Type-I progressive hybrid censoring sample, we obtain maximum likelihood estimator of unknown parameter when the parent distribution belongs to proportional hazard rate family. We derive the conditional probability density function of the maximum likelihood estimator using moment-generating function technique. The exact confidence interval is obtained and compared by conducting a Monte Carlo simulation study for burr Type XII distribution. Finally, we obtain the Bayes and posterior regret gamma minimax estimates of the parameter under a precautionary loss function with precautionary index k = 2 and compare their behavior via a Monte Carlo simulation study.