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111.
Through a Personal Emergency Link system, the Senior Citizen Home Safety Association has rendered 24-hour care to more than 111,000 service users in Hong Kong who are mostly vulnerable seniors and chronic invalids living alone or living with their elderly spouses/caregivers only. This article will describe how the Personal Emergency Link system is used to link seniors living in the community. Measures taken to prevent failure of the system will be described. With the use of different technology applications, many human touches and warm caregiving are rendered to the elderly and needy.  相似文献   
112.
对川东T构造须家河组含气储层的地球物理响应特征进行了分析,采用地质与地球物理互馈结合的手段,通过合成记录正演、储层置换的方法进行了其地质形成机制研究。结果表明:T构造须家河组含气储层主要表现为低频率、弱振幅(近空白)反射,其形成机制主要有两方面的因素,一是含气层速度的降低导致振幅减弱,在薄层叠加效应的作用下,含气层下部出现弱振幅;二是含气层对高频的吸收作用,低频率导致砂泥岩互层无法分辨,表现为弱振幅。最终形成的低频率、弱振幅特征是这两种因素的综合响应,该特征在T构造高部位可以作为识别含气储层的标志。  相似文献   
113.
Response surface methodology is widely used for developing, improving, and optimizing processes in various fields. In this article, we present a method for constructing three-level designs in order to explore and optimize response surfaces combining orthogonal arrays and covering arrays in a particular manner. The produced designs achieve the properties of rotatability, predictive performance and efficiency for the estimation of a second-order model.  相似文献   
114.
Quality of life (QOL) has become an important component of health. By using the methodology of psychometric theory, we examine the item properties of the WHOQOL-BRIEF. Samejima’s graded response model with natural metrics of the logistic response function was fitted. The results showed items with negative natures were less discriminating. Items written in a specific way were more suitable to assess certain subgroups. The national items showed variation in discriminatory power. Questions measuring objective and specific issues performed worse than items assessing general aspects of the QOL.  相似文献   
115.
Severe departures from normality occur frequently for null distributions of statistics associated with applications of mulLi-response permutation procedures (MRPP) for either small or large finite populations. This paper describes the commonly encountered situation associated with asymptotic non-normality for null distributions of MRPP statistics which does not depend on the underlying multivariate distribution. In addition, this paper establishes the existence of a non-degenerate underlying distribution for which the null distributions of MRPP statistics are asymptotically non-normal for essentially all size structure configurations. It is known that MRPP statistics are symmetric versions of a broader class of statistics, most of which are asymmetric. Because of the non-normality associated with null distributions of MRPP statistics, this paper includes necessary results for inferences based on the exact first three moments of anv statistic in this broader class (analogous to existing results for MRPP statistics).  相似文献   
116.
Standard resulrs on the extrema of quotients of quadratic forms are extended to the non-negative definite case. The maximum and the set over which it is achieved are characterized explicitly both in terms of generalized inverse matrices and generalized eigenvalues. These results become the basis of Scheffe type multiple comparisons in the usual way. To demonstrate their application to statistics with singular covariance matrices, the method is detailed for Mantel-Haenszel, Breslow, and Cox statistics. An example is presented illustrating a situation where the proposed Scheffe type comparisons may be better than the pairwise method.  相似文献   
117.
Correlated binary data arise frequently in medical as well as other scientific disciplines; and statistical methods, such as generalized estimating equation (GEE), have been widely used for their analysis. The need for simulating correlated binary variates arises for evaluating small sample properties of the GEE estimators when modeling such data. Also, one might generate such data to simulate and study biological phenomena such as tooth decay or periodontal disease. This article introduces a simple method for generating pairs of correlated binary data. A simple algorithm is also provided for generating an arbitrary dimensional random vector of non-negatively correlated binary variates. The method relies on the idea that correlations among the random variables arise as a result of their sharing some common components that induce such correlations. It then uses some properties of the binary variates to represent each variate in terms of these common components in addition to its own elements. Unlike most previous approaches that require solving nonlinear equations or use some distributional properties of other random variables, this method uses only some properties of the binary variate. As no intermediate random variables are required for generating the binary variates, the proposed method is shown to be faster than the other methods. To verify this claim, we compare the computational efficiency of the proposed method with those of other procedures.  相似文献   
118.
英国小说家艾丽丝·默多克的代表作《黑王子》是一部具有实验性质的小说,从多个层面探讨了生活的本质,艺术与生活的关系。包括情节、引喻、叙事策略以及结构安排等构成了小说的召唤结构,共同作用于读者的阅读活动,使读者能够自觉地建构小说的意义,对其哲学内涵作出反应。  相似文献   
119.
对于所采集的条码图像,为了适应实时性的要求,以得到不同光照条件下的最佳阈值,该文提出了把直方图双峰法、OTSU法及NLNiblack阈值法结合起来的改进的自适应阈值法。实验证明了该方法具有高效性和稳定性。为了在条码分割图像中获取QR码的4个顶点,首先,根据3个位置探测图形的特性提出了一种新的方法以求取对应的3个顶点,同时利用QR码的特征提出挖空算法获取条码的边缘,再采用过已知点的Hough变换得到第4个顶点。实验证明该算法在各种采集条件下可有效地得到QR码的4个顶点。  相似文献   
120.
In this paper we consider the problem of obtaining best linear unbiased estimators of individual response coefficients in a Random Coefficient Linear Regression (RCR} Model, comparing alternative estimators for these response vectors through a simulation study. We also provide an empirical example that illustrates the estimation procedure proposed here.  相似文献   
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