Modeling time series data with semi-reflective boundaries

Time series data are increasingly common in many areas of the health sciences, and in some instances, may have natural boundaries serving as performance guidelines or as thresholds associated with adverse outcomes. Such boundaries may be labeled as semi-reflective, in that the time series values have an increased chance of returning towards middle levels as the boundaries are approached, but boundaries can still be breached. In this paper we review a model that was previously proposed for such data and we investigate its statistical properties. Specifically, this model consists of a third-order auto-regressive projection component, parameterized as a constrained linear combination of linear, flat, and quadratic trends, and an error term that uses a logistic regression model for its sign. We describe and compare a previously-proposed estimation method with a modified version thereof, using computer simulations, as well as data examples from heart monitoring and from a driving simulator. We find that the two methods tend to give different results, with the modified technique having lower bias and more accurate confidence intervals than the previously-proposed method.     

水泥土桩复合地基承载力取值方法探讨

水泥土桩复合地基承载力的确定,目前常用的方法是现场载荷试验,并被公认为是比较可靠的方法。结合工程实测资料,讨论了用该法确定水泥土极复合地基承载力的取值问题,提出用相对变形S认的取值是合理的。同时通过一定数量的水泥土单桩静载荷试验、单极复合地基载荷试验和多桩复合地基载荷试验对比分析,说明用一组极和桩间土所组成的单元作进行承载力试验,更接近实际复合地基的受力性状和承载机理。     

无人机载3mm波脉冲雷达信号处理系统

介绍了一个采用专用ＤＳＰ芯片ＰＤＳＰ１６５１０以及大规模ＰＬＤ芯片ＰＬＥＸ１０Ｋ实现的无人机载３ｍｍ波脉冲雷达信号处理系统。并对机载雷达普遍存在的主杂波抑制问题,提出一种在回波视频信号上抑制主杂波的方法。该系统具有处理速度快、分辨率高和灵活的可编程方式的特点,以及重量轻、体积小、可靠性高的工程实用性,并给出了具体实验测试结果。     

Quantitative microbiological risk assessment of nontyphoidal Salmonella in ground pork in households in Chengdu,China

Foodborne disease caused by nontyphoidal Salmonella (NTS) is one of the most important food safety issues worldwide. The objectives of this study were to carry out microbial monitoring on the prevalence of NTS in commercial ground pork, investigate consumption patterns, and conduct a quantitative microbiological risk assessment (QMRA) that considers cross-contamination to determine the risk caused by consuming ground pork and ready-to-eat food contaminated during food handling in the kitchen in Chengdu, China. The food pathway of ground pork was simplified and assumed to be several units according to the actual situation and our survey data, which were collected from our research or references and substituted into the QMRA model for simulation. The results showed that the prevalence of NTS in ground pork purchased in Chengdu was 69.64% (95% confidence interval [CI], 60.2–78.0), with a mean contamination level of −0.164 log CFU/g. After general cooking, NTS in ground pork could be eliminated (contamination level of zero). The estimated probability of causing salmonellosis per day was 9.43E-06 (95% CI: 8.82E-06–1.00E-05), while the estimated salmonellosis cases per million people per year were 3442 (95% CI: 3218–3666). According to the sensitivity analysis, the occurrence of cross-contamination was the most important factor affecting the probability of salmonellosis. To reduce the risk of salmonellosis caused by NTS through ground pork consumption, reasonable hygiene prevention and control measures should be adopted during food preparation to reduce cross-contamination. This study provides valuable information for household cooking and food safety management in China.     

Simultaneous semi-sequential testing of dual alternatives for pattern recognition

In this paper, we propose a new nonparametric simultaneous test for dual alternatives. Simultaneous tests for dual alternatives are used for pattern detection of arsenic contamination level in ground water. We consider two possible patterns, namely, monotone shift and an umbrella-type location alternative, as the dual alternatives. Pattern recognition problems of this nature are addressed in Bandyopadhyay et al. [5], stretching the idea of multiple hypotheses tests as in Benjamini and Hochberg [6]. In the present context, we develop an alternative approach based on contrasts that helps us to detect three underlying pattern much more efficiently. We illustrate the new methodology through a motivating example related to highly sensitive issue of arsenic contamination in ground water. We provide some Monte-Carlo studies related to the proposed technique and give a comparative study between different detection procedures. We also obtain some related asymptotic results.     

英汉语中“焦点/背景”设置对比反映的认知模式差异

“焦点／背景”理论于上世纪60年代从心理学研究走向语言学研究的领域,并带来了丰硕的研究成果。论文以该理论为基础,通过对比研究英汉语中“焦点”与“背景”的设置,得出英汉语人群的不同认知模式。英语中通常呈现焦点前置的原则,也就是“焦点--背景”的认知模式;对比之下,汉语则呈现焦点后置的原则,及“背景--焦点”的认知模式。     

海杂波背景下的双参数单元平均恒虚警检测器

介绍了海杂波的幅度分布模型,指出了对于同一门限系数"尖锐"海杂波背景下的虚警率要明显高于噪声背景下的虚警率,提出了双参数单元平均恒虚警(CA-CFAR)检测器的结构框图,仿真分析了其检测性能.最后分别利用双参数CA-CFAR检测器和常规CA-CFAR检测方法对实测数据进行处理和比较,指出在虚警率一定的前提下前者相对于后两者在空间上可以自适应地改变门限系数以有效地抑制海杂波引起的高虚警.     

“反本质论”的学术后果--对中国儿童文学史重大问题的辨析

近年来,儿童文学学术界出现了反本质论这一重要学术动向。对反本质论者的学术研究展开富于学理的深入讨论,这是谋求儿童文学学科的学术深化的一个契机。借鉴实用主义“真理”观的哲学方法,不针对本质论和反本质论作孰是孰非的理论论证,而是对“反本质论”这一工具的实际使用效果进行具体考察,揭示当下的反本质论者在中国儿童文学史的一些重大问题研究上出现的学术失据状况,以期引起学界对反本质论的负面学术效果的反思,并倡导学界保持凝视、谛视、审视这三重学术目光。     

《西江月·夜行黄沙道中》的认知诗学解读

《西江月.夜行黄沙道中》这首词是辛弃疾贬官闲居江西时的作品。这首词着意描写黄沙岭的夜景——明月清风,疏星稀雨,鹊惊蝉鸣,稻花飘香,蛙声一片。词从视觉、听觉和嗅觉三方面抒写夏夜的山村风光。由此可见作者辛弃疾将自身亲身体验夜行黄沙道中的所见所听所闻的所感通过诗的语言表达出来。诗歌是人类强烈情感导致的一种特殊认知活动的表达方式,而语言正是人类认知的结果,诗歌是人们特殊概念化过程的结果和表达,诗歌是人类认知世界（精神）体验的一种表达方式。由此看来,诗歌也是基于认知体验的过程;同时提出：认知诗学这一全新解读方法也可对本土作品进行分析。     

基于图形背景理论的《哈利·波特》认知解读

图形与背景理论是认知文体学中的重要内容.图形指某一认知概念或感知中突出的部分,背景则为突出图形而衬托的部分,两者不可同时被感知.认知文体学中,图形与背景理论不仅可以对语法现象进行详细的分析,也可以对语篇的内容进行探究.运用这一理论对近年来颇为畅销的<哈利*波特>系列小说进行认知解读,为赏析该小说开辟一个新视角.