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91.
王宇坤 《中国石油大学学报(社会科学版)》2016,(5):41-46
中国实行四级两审终审的审级制度,这种审级制度设置源于法律移植、历史传统、地缘环境以及认知理念等因素的考量。但是当下正在积极推行试点的刑事案件速裁程序改革、人民陪审员制度改革,强烈冲击了司法裁判生效过程的一元化特征,并对各级刑事审判机关的职能划分提出了挑战,进而影响刑事审级制度的设置。为了更好地适应社会结构的转型和司法改革的推进,中国刑事审级制度的设置应当进行调整,实现司法裁判生效过程的多元化,并重塑各级刑事审判机关的职能划分。 相似文献
92.
未焊透是压力管道焊接接头常见缺陷之一,严重时会导致管道的承载能力明显降低,进而引发严重的安全事故。
目前我国的《在用工业管道定期检验规程》中对未焊透管道的定级是很保守的,为了减少对未焊透缺陷的返修,文章采
用非线性有限元分析的方法,通过简化未焊透管道的影响因素,并研究在不同载荷工况下管道失效模式与缺陷尺寸的关
系,获得了未焊透管道的极限载荷曲线簇;再运用塑性力学分析方法对有限元分析结果进行筛选,得到了焊接缺陷的安
全尺寸;最终通过试验验证极限载荷数值分析结果的合理性。研究结果表明含有超标焊接缺陷(如未焊透)的管道不通
过复杂应力计算和安全评定即可在保证安全前提下最大限度地使用。 相似文献
93.
A Note on the Large Sample Properties of Estimators Based on Generalized Linear Models for Correlated Pseudo‐observations 下载免费PDF全文
Pseudo‐values have proven very useful in censored data analysis in complex settings such as multi‐state models. It was originally suggested by Andersen et al., Biometrika, 90, 2003, 335 who also suggested to estimate standard errors using classical generalized estimating equation results. These results were studied more formally in Graw et al., Lifetime Data Anal., 15, 2009, 241 that derived some key results based on a second‐order von Mises expansion. However, results concerning large sample properties of estimates based on regression models for pseudo‐values still seem unclear. In this paper, we study these large sample properties in the simple setting of survival probabilities and show that the estimating function can be written as a U‐statistic of second order giving rise to an additional term that does not vanish asymptotically. We further show that previously advocated standard error estimates will typically be too large, although in many practical applications the difference will be of minor importance. We show how to estimate correctly the variability of the estimator. This is further studied in some simulation studies. 相似文献
94.
Shaun R. Seaman Daniel Farewell Ian R. White 《Scandinavian Journal of Statistics》2016,43(4):996-1018
Linear increments (LI) are used to analyse repeated outcome data with missing values. Previously, two LI methods have been proposed, one allowing non‐monotone missingness but not independent measurement error and one allowing independent measurement error but only monotone missingness. In both, it was suggested that the expected increment could depend on current outcome. We show that LI can allow non‐monotone missingness and either independent measurement error of unknown variance or dependence of expected increment on current outcome but not both. A popular alternative to LI is a multivariate normal model ignoring the missingness pattern. This gives consistent estimation when data are normally distributed and missing at random (MAR). We clarify the relation between MAR and the assumptions of LI and show that for continuous outcomes multivariate normal estimators are also consistent under (non‐MAR and non‐normal) assumptions not much stronger than those of LI. Moreover, when missingness is non‐monotone, they are typically more efficient. 相似文献
95.
A problem of using a non‐convex penalty for sparse regression is that there are multiple local minima of the penalized sum of squared residuals, and it is not known which one is a good estimator. The aim of this paper is to give a guide to design a non‐convex penalty that has the strong oracle property. Here, the strong oracle property means that the oracle estimator is the unique local minimum of the objective function. We summarize three definitions of the oracle property – the global, weak and strong oracle properties. Then, we give sufficient conditions for the weak oracle property, which means that the oracle estimator becomes a local minimum. We give an example of non‐convex penalties that possess the weak oracle property but not the strong oracle property. Finally, we give a necessary condition for the strong oracle property. 相似文献
96.
Grzegorz Wyłupek 《Scandinavian Journal of Statistics》2016,43(4):1103-1123
The paper proposes a new test for detecting the umbrella pattern under a general non‐parametric scheme. The alternative asserts that the umbrella ordering holds while the hypothesis is its complement. The main focus is put on controlling the power function of the test outside the alternative. As a result, the asymptotic error of the first kind of the constructed solution is smaller than or equal to the fixed significance level α on the whole set where the umbrella ordering does not hold. Also, under finite sample sizes, this error is controlled to a satisfactory extent. A simulation study shows, among other things, that the new test improves upon the solution widely recommended in the literature of the subject. A routine, written in R, is attached as the Supporting Information file. 相似文献
97.
98.
This paper deals with the problem of predicting the real‐valued response variable using explanatory variables containing both multivariate random variable and random curve. The proposed functional partial linear single‐index model treats the multivariate random variable as linear part and the random curve as functional single‐index part, respectively. To estimate the non‐parametric link function, the functional single‐index and the parameters in the linear part, a two‐stage estimation procedure is proposed. Compared with existing semi‐parametric methods, the proposed approach requires no initial estimation and iteration. Asymptotical properties are established for both the parameters in the linear part and the functional single‐index. The convergence rate for the non‐parametric link function is also given. In addition, asymptotical normality of the error variance is obtained that facilitates the construction of confidence region and hypothesis testing for the unknown parameter. Numerical experiments including simulation studies and a real‐data analysis are conducted to evaluate the empirical performance of the proposed method. 相似文献
99.
随着大众旅游时代的到来,出游人数激增,极易形成高度聚集的游客群,而高聚集的游客群难控难疏,易导致安全事故发生。加强和完善游客高聚集场所的安全管理已成为旅游管理部门一项紧迫而重要的任务。本文主要以国内外政策法规中关于人员密集场所、公共聚集场所的表述为出发点,结合已有研究成果,借鉴人员密集场所的定义,界定“游客高聚集场所”的概念,并就游客高聚集场所的特征进行了讨论;在此基础上,分析了游客高聚集场所面临的风险类型及其相关诱发因素;最后,根据现有人员密集场所的研究进展提出了游客高聚集场所的相关研究议题。 相似文献
100.
在既定资源约束下实现粮食产出最大化是粮食生产安全的核心。而今旨在提升粮食竞争力的农业规模经营虽得到政府力推,却并非保障国家粮食安全的充分条件。在梳理规模经营与粮食安全保障相关争论的基础上,结合调研资料,依次回应了规模经营后农地是否大概率用于种粮、规模经营是否可持续以及规模经营能否保障粮食产量三个焦点问题。研究发现,与小农经营相比,规模经营与种植结构“非粮化”虽无必然联系,却存在规模经济不显著及单产提升乏力等问题。对此,一方面应强化小农扶持力度,巩固维系小农群体的粮食保障功能;另一方面应调整规模经营主体的政策干预结构,除非在规模经济与土地产出率不一致的情形下,应最大化避免对规模经营主体的直接干预,降低政策的扭曲效应,推动规模经济实现。 相似文献