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31.
THE 'HYBRID' TECHNIQUE FOR RISK ANALYSIS OF SOME DISEASES   总被引:1,自引:0,他引:1  
51. IntroductionSince the theory of fuszy set was introduced by Lotfi A. Zadeh in 1965, fuzzy techniquehas developed rapidly and has been successfully aPplied into many fields.In receat yeaJrs3 a new and promising way of using the fuzzy technique is combinedwith other deterministic and statistica1 methods. The so-called 'hybrid' technique has beenaPplied to insurance business and achieved positive results (see [1, 2], etc.).Based on the data obtained from a survey recelltly made in a commun…  相似文献   
32.
Based on the data obtained from a survey recently made in Shanghai, this paper presents the hybrid technique for risk analysis and evaluation of some diseases. After determination of main risk factors of these diseases by analysis of variance, the authors introduce a new concept ‘Illness Fuzzy Set‘ and use fuzzy comprehensive evaluation to evaluate the risk of suffering from a disease for residents. Optimal technique is used to determinethe weights wi in fuzzy comprehensive evaluation, and a new method ‘Improved Information Distribution‘ is also introduced for the treatment of small sample problem. It is shown that the results obtained by using the hybrid technique are better than by using single fuzzy technique or single statistical method.  相似文献   
33.
该文首次用几何方法研究回归模型中数据变换参数及其子集参数的渐近置信域问题.由于文中讨论的是一般的数据变换多参数的渐近置信域的曲率表示,从而有关结论适用于各种数据变换如著名的Box-Cox变换、带有漂移参数的幂变换等变换中变换参数的渐近置信域的曲率表示.  相似文献   
34.
本文从我国统计信息事业的现状,提出了关于第一类统计与第二类统计。同时指出统计信息事业的迅速发展与繁荣,首先必须实现两类统计的相互渗透;其二必须与计算机技术密切结合,以建立起各级各类统计信息的高速公路,使统计信息更好地为我国的科技、经济、社会的全面发展提供有效的服务。  相似文献   
35.
大学生综合素质的问卷调查与结论   总被引:4,自引:0,他引:4  
本文给出的大学生综合素质问卷调查的若干结论,是通过对武汉大学、中国科技大学等18所高校参与的大学生综合素质问卷调查所获统计数据,进行了多层次、多方面、多视角的比较与分析所得。我们期望这些研究结果,能给大学的领导与广大教育工作者进一步了解在校大学生的现状、特点、问题以及对如何全面提高大学生的培养质量等提供帮助。  相似文献   
36.
《Electrophoresis》2018,39(7):909-923
Rapid advances in mass spectrometry (MS) and nuclear magnetic resonance (NMR)‐based platforms for metabolomics have led to an upsurge of data every single year. Newer high‐throughput platforms, hyphenated technologies, miniaturization, and tool kits in data acquisition efforts in metabolomics have led to additional challenges in metabolomics data pre‐processing, analysis, interpretation, and integration. Thanks to the informatics, statistics, and computational community, new resources continue to develop for metabolomics researchers. The purpose of this review is to provide a summary of the metabolomics tools, software, and databases that were developed or improved during 2016–2017, thus, enabling readers, developers, and researchers access to a succinct but thorough list of resources for further improvisation, implementation, and application in due course of time.  相似文献   
37.
Summary The selective inhibition of COX-2 isozymes should lead to a new generation of NSAIDs with significantly reduced side effects; e.g. celecoxib (Celebrex®) and rofecoxib (Vioxx®). To obtain inhibitors with higher selectivity it has become essential to gain additional insight into the details of the interactions between COX isozymes and NSAIDs. Although X-ray structures of COX-2 complexed with a small number of ligands are available, experimental data are missing for two well-known selective COX-2 inhibitors (rofecoxib and nimesulide) and docking results reported are controversial. We use a combination of a traditional docking procedure with a new computational tool (Contact Statistics analysis) that identifies the best orientation among a number of solutions to shed some light on this topic.  相似文献   
38.
应用电感中耦合等离子体发射光谱法(ICP-AES),测定了海口市214例人发中锌、失、钙、锰的含量,按照年龄不同划分为婴儿组、幼儿组、大儿童和青少年组及成人组。对同一元素不同年龄组进行统计分析,表明幼儿和青少年处于生长发育时期最易缺乏微量元素。  相似文献   
39.
A gas chromatography-mass spectrometry GC-MS method was established to determine three different synthetic musksSMsfrom ground water. Dichloromethane as the extracting solventthe concentrated extracts were tested by GC-MS using the external standard quantitative method. Each sample was extracted three times with 40 mL dichloromethane respectively. The linearity test was carried out in the range of 20.0 to 2000 μµg/L the relative standard deviationRSDRRFof average relative response factor was less than 8.7%and the limits of detectionLODswere in the range of 0.007 to 0.012 μµg/L. The recoveries of three spiked ground water samples were all between 98.1% and 117.0%and the relative standard deviations were less than 13%. Musk xylene in the ground water sample was 0.013 μµg/Land the spiked real sample had the recoveries higher than 80%. This method was suitable for the detection of trace SMs in ground water. © 2022, Youke Publishing Co.,Ltd. All rights reserved.  相似文献   
40.
对复杂环境介质中的典型污染物进行快速、精准甚至远程连续自动的检测,是控制环境污染、确保环境和生态安全的重要前提。近年来,基于色谱技术的典型环境污染物快速检测方法发展迅猛,主要包括样品快速制备和目标物快速检测两方面。辅助萃取、快速液相萃取、QuEChERS等样品前处理方法具有萃取效率高、溶剂消耗少、操作简便快速等优点。快速检测技术可在几秒到半小时内提供检测结果,主要包括实验室和现场检测。本文综述了2019年以来基于色谱技术的典型环境污染物快速检测研究新进展。介绍了萃取技术和基于试验设计的样品快速制备,实验室快速检测、便携仪器现场检测及遥感技术远程检测,提出了色谱技术快速检测环境污染物的挑战和展望。  相似文献   
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