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31.
Uniform designs are widely used in various scientific investigations and industrial applications. By considering all possible level permutation of the factors, a connection between average centered L2-discrepancy and generalized wordlength pattern for asymmetrical fractional factorial designs is derived. Moreover, we present new lower bounds to the average centered L2-discrepancy for symmetrical and asymmetrical U-type designs. For illustration of the theoretical results, the lower bounds for symmetrical and asymmetrical U-type designs are tabulated, and numerical results indicate that our lower bounds behave well and can be recommended for use in practice.  相似文献   
32.
In a special paired sample case, Hotelling’s T2 test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given.  相似文献   
33.
BackgroundIn the Palestinian community, lifestyle changes, rapid urbanization and socioeconomic development, stress, smoking, and changes in food habits has increased the risk of non-communicable diseases especially diabetes mellitus. Diabetes complications can be prevented if the glycemic status of patients with diabetes is maintained within a nearly normal range. Therefore, patient education is critical in controlling blood glucose levels within the normal range.ObjectiveThis study aimed at measuring the effect of diabetes educational intervention program for patients suffering from type 2 diabetes attending the Diabetes Clinic in Tulkarim Directorate of Health.MethodsA short duration observational study involving pre- and post-test educational intervention program was carried out on a relatively small number of type 2 diabetes patients at the Diabetes Clinic in Tulkarim Directorate of Health. In total, 215 patients attended a group-based 4 h educational intervention session about diabetes. The program included explaining diabetes mellitus-symptoms, risk factors, types, treatment and complications and main aspects of self-care of the disease (foot care, eye care, and blood glucose monitoring), main aspects of dietary management, weight reduction, blood pressure, smoking cessation, periodic investigations, home monitoring and importance of physical activity. Knowledge evaluation questionnaire were evaluated pre- and post-study. Anthropometric measurements such as body weight (WT), body mass index (BMI) and laboratory tests such as fasting blood glucose (FBG), hemoglobin A1C (HbA1c), cholesterol (Chol), and triglycerides (TG) were measured both at the beginning and at the end of the study. Significance of the results was assessed by paired t-test at 95% confidence interval.ResultsThe participant’s mean age was 51.07 that ranged between 31 and 70 years. For a total of 215 participants, 41.4% were males and 58.6% were females. The mean weight before educational intervention was 80.81 ± 14.95 kg (82.6 kg for males and 79.5 kg for females) that decreased to 78.9 ± 14.33 kg (81.1 kg for males and 77.3 kg for females) after educational intervention program. The BMI also decreased significantly after educational intervention. The mean fasting blood sugar was 188.65 ± 71.45 mg/dL before educational intervention that decreased to 177.7 ± 66.11 mg/dL after the educational intervention (p = 0.049). The mean glycosylated hemoglobin was 8.57 ± 1.21 before educational intervention that decreased to 7.95 ± 1.42 after educational intervention. The mean value of cholesterol before educational intervention was 183.27 ± 37.74 mg/dL that decreased to 169.57 ± 34.23 mg/dL after educational intervention. The mean triglycerides value decreased after educational intervention from 209.85 ± 171.04 mg/dL to 183.28 ± 152.4 mg/dL (p = 0.025). The mean score of knowledge questionnaire before educational intervention was 60.6 ± 20.65 that increased to 78.1 ± 13.4 after conducting educational intervention.ConclusionsDiabetes education was found to be effective on BMI, FBG, HbA1c, Chol, TG, and knowledge.RecommendationsDiabetes education is a cornerstone in the management and care of diabetes and should be an integral part of health planning involving patient’s family, diabetes care team, community, and decision makers in the education process.  相似文献   
34.
自适应共振模型是为了能够分类任意次序模拟输入模式而设计的,它可以按任意精度对输入的模拟观察矢量进行分类,较好地解决了前稳定性和灵活性问题,同时能够避免对网络先前所学的学习模式修改。本文将ART2模型应用于信用风险评估,通过实证比较研究,结果显示应用自适应共振模型进行信用风险评估在精度和准确性上,都优于其他神经网络模型和统计方法。  相似文献   
35.
通过解剖典型的个案,概括出作为无形文化资产(遗产)的文学,从无形转为有形的物化形态,衍生为产业链,从而走向当代价值实现的三个重要前提条件;并论述了“后文学产业链”的三级资源化过程,以及被资源化之后,传统文学活动系统中的作家、作品、读者三大要素的地位和功能的蜕变,分析了文学作为审美意识形态具有“不可资源化”的特质。  相似文献   
36.
国内外对L2句子加工的研究存在着较大区别。国外偏重于探讨句子加工的心理机制本身,而国内不仅探讨句子加工的心理机制本身,而且还注重探讨句子加工的心理机制所说明的问题,分析L2句子加工是否接近或相似于L1句子加工。目前,该领域的研究主要存在三种主要流派:模块说、交互说和平行说。多数学者认为L2句子加工是句法和语义加工交织的过程,即多数人接受了交互说。少数学者认为语义加工优先于句法加工。至于平行说,最近L2句子加工研究鲜有成果支持此理论。  相似文献   
37.
P2P技术与网络传播的未来   总被引:4,自引:0,他引:4  
伴随着P2P技术和商业应用的发展,P2P技术对于未来网络传播可能产生的影响也成为一个令 人关注的问题。从目前来看,P2P技术对于网络传播的影响主要包括以下几方面:网络信息共享与 利用的方式与程度将进一步改变;围绕P2P技术思想展开的软件与信息产品开发,将在一定程度上 决定作为媒体的网络的未来面貌;P2P带来的去中心化特点将使互联网管理的难度进一步增加; P2P可能成为媒体间的交流与合作的新平台,也可能加速媒体形态的演化。从总体看,P2P技术未 来的社会影响程度,取决于政治、经济等各种力量的博弈结果,而这也将最终影响着互联网的未来。  相似文献   
38.
In high-dimensional linear regression, the dimension of variables is always greater than the sample size. In this situation, the traditional variance estimation technique based on ordinary least squares constantly exhibits a high bias even under sparsity assumption. One of the major reasons is the high spurious correlation between unobserved realized noise and several predictors. To alleviate this problem, a refitted cross-validation (RCV) method has been proposed in the literature. However, for a complicated model, the RCV exhibits a lower probability that the selected model includes the true model in case of finite samples. This phenomenon may easily result in a large bias of variance estimation. Thus, a model selection method based on the ranks of the frequency of occurrences in six votes from a blocked 3×2 cross-validation is proposed in this study. The proposed method has a considerably larger probability of including the true model in practice than the RCV method. The variance estimation obtained using the model selected by the proposed method also shows a lower bias and a smaller variance. Furthermore, theoretical analysis proves the asymptotic normality property of the proposed variance estimation.  相似文献   
39.
冯博  叶绮文  陈冬宇 《管理科学》2017,20(4):113-126
P2P ( 个人对个人) 网络借贷是指通过网络借贷平台,在全球范围内实现个人与个人或小微企业间的小额信用借贷交易. P2P 网络借贷作为全新的互联网金融服务受到商业界的高度关注,而且发展成为学术研究的国际前沿领域. 对 P2P 网络借贷相关研究文献进行了综述,具体从影响借贷交易的信息因素、羊群效应以及社交网络等 3 个方面分析了该领域研究的现状和发展脉络. 因为中国已超越美国成为全球最大的 P2P 网络借贷交易市场,所以结合中国的具体情境和问题,提出了未来研究工作的展望.  相似文献   
40.
Fractional factorial (FF) designs are no doubt the most widely used designs in experimental investigations due to their efficient use of experimental runs. One price we pay for using FF designs is, clearly, our inability to obtain estimates of some important effects (main effects or second order interactions) that are separate from estimates of other effects (usually higher order interactions). When the estimate of an effect also includes the influence of one or more other effects the effects are said to be aliased. Folding over an FF design is a method for breaking the links between aliased effects in a design. The question is, how do we define the foldover structure for asymmetric FF designs, whether regular or nonregular? How do we choose the optimal foldover plan? How do we use optimal foldover plans to construct combined designs which have better capability of estimating lower order effects? The main objective of the present paper is to provide answers to these questions. Using the new results in this paper as benchmarks, we can implement a powerful and efficient algorithm for finding optimal foldover plans which can be used to break links between aliased effects.  相似文献   
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