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异总体统计问题的Bayes分析 被引量:10
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作者 张士峰 杨万君 《战术导弹技术》 2003年第2期33-37,共5页
讨论了异总体统计信息的处理方法 .运用Bayes方法将各阶段的试验信息以及总体分布参数的序化关系信息有效地融合 ,得到了设备性能参数的验后分布 ,进而可以对性能参数进行评估 .以设备精度评估为例分析了这种处理方法 。
关键词 异总体统计 BAYES分析 武器系统 信息处理 分布参数 序化关系信息 试验信息 精度评估 GAMMA分布
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国内生存分析在可靠性数据分析中的应用进展 被引量:5
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作者 王卓健 虞健飞 +1 位作者 王礼沅 沈安慰 《火力与指挥控制》 CSCD 北大核心 2015年第1期1-4,共4页
针对可靠性数据分析中遇到的小样本、异总体、删失和截尾问题,引入现代统计学的重要分支——生存分析理论,分别从参数生存分析模型、非参数生存分析模型和半参数生存分析模型3个方面分析了国内生存分析在可靠性数据分析中的研究现状与... 针对可靠性数据分析中遇到的小样本、异总体、删失和截尾问题,引入现代统计学的重要分支——生存分析理论,分别从参数生存分析模型、非参数生存分析模型和半参数生存分析模型3个方面分析了国内生存分析在可靠性数据分析中的研究现状与应用进展。 展开更多
关键词 生存分析 可靠性 删失 截尾 异总体 小样本
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装备测试性增长过程的贝叶斯验证方法 被引量:4
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作者 尹园威 尚朝轩 +2 位作者 蔡金燕 马彦恒 李刚 《振动.测试与诊断》 EI CSCD 北大核心 2016年第3期488-491,603,共4页
现有测试性验证试验方案需要较多故障样本,存在测试性验证时间长、结果置信度低的问题,为此提出一种装备测试性增长模型的贝叶斯验证方法,在小子样、异总体的情况下进行测试性验证。建立装备测试性水平动态增长的数学模型,依据已有的研... 现有测试性验证试验方案需要较多故障样本,存在测试性验证时间长、结果置信度低的问题,为此提出一种装备测试性增长模型的贝叶斯验证方法,在小子样、异总体的情况下进行测试性验证。建立装备测试性水平动态增长的数学模型,依据已有的研制阶段的数据进行求解,得到测试性增长模型的具体参数值,并对测试性水平进行预测。确定测试性水平的先验分布,使用最大熵法求解分布参数,采用贝叶斯理论融合现场试验数据得到后验分布,实现对装备测试性水平的验证。实例分析表明,该方法在较少样本量的情况下能够提高验证结果的置信度,降低双方风险。 展开更多
关键词 测试性增长 测试性验证 异总体 贝叶斯理论
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Effect of total isoflavones from pueraria lobata on the expressions of preproenkephalin, prodynorphin and D2 dopamine receptor mRNA in PC12 cells induced by MPP^+
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作者 Miaoxian Dong Chengchong Li +3 位作者 Yutao Gen Chun Zhang Xiaoming Li Yingcai Niu 《The Chinese-German Journal of Clinical Oncology》 CAS 2010年第1期48-52,共5页
Objective: The aim of the study was to observe the effect of total isoflavones from pueraria Iobata (TIP) on D2 dopamine receptor mRNA, preproenkephalin mRNA and prodynorphin mRNA expressions in Parkinson's disea... Objective: The aim of the study was to observe the effect of total isoflavones from pueraria Iobata (TIP) on D2 dopamine receptor mRNA, preproenkephalin mRNA and prodynorphin mRNA expressions in Parkinson's disease (PD) model cells induced by 1-methyl-4-phenylpyridinium ion (MPP^+). Methods: TIP was dissolved in 0.1 M NaOH and added to the culture medium at a final concentrations of 50 mg/L, 100 mg/L and 200 mg/L. Some cells (control) were exposed to 0.001 M NaOH. TIP was added to PC12 cells 30 min prior to the administration of MPP^+. TIP and MPP^+ remained in the culture medium for 96 h. D2 dopamine receptor mRNA, preproenkephalin mRNA and prodynorphin mRNA expressions were assayed by real-time quantitative reverse transcription-PCR. Results: The D2 dopamine receptor mRNA and preproenkephalin mRNA expressions were up-regulated in MPP^+ group compared with the control group, and prodynorphin mRNA expression was down-regulated in that. The D2 dopamine receptor mRNA expression being down-regulated and prodynorphin mRNA expression being up-regulated in TIP group compared with the MPP^+ group. And there was no effect of TIP on preproenkephalin gene expression in PC12 cells induced by MPP^+. Conclusion: The results suggest that TIP down-regulates the D2 dopamine receptor mRNA expression, up-regulates prodynorphin mRNA expression and not affects preproenkephalin gene expression in PC12 cells induced by MPP^+. 展开更多
关键词 Parkinson's disease (PD) total isoflavones from pueraria Iobata (TIP) PREPROENKEPHALIN D2 dopamine receptor PRODYNORPHIN 1-methyl-4-phenylpyddinium ion (MPP^+)
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Quality Assessment of Drinking Water in Tanta City, Egypt
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作者 Maha Abdelfattah Khalil Zenhom El-Said Salem +1 位作者 Saly Farouk Gheda Moustafa Mohamed E1-Sheekh 《Journal of Environmental Science and Engineering(B)》 2013年第5期257-275,共19页
The physico-chemical and biological (algal and bacterial) quality of tap water in Tanta City were elucidated. Samples were collected during December 2011, covering all the water plants and the areal extension of the... The physico-chemical and biological (algal and bacterial) quality of tap water in Tanta City were elucidated. Samples were collected during December 2011, covering all the water plants and the areal extension of the pipe line network in Tanta. Total dissolved solids content classifies water origin into surface water, shallow and deep groundwater. Fe, Mn and hardness in some samples of groundwater origin are obviously exceeding the WHO (World Health Organization) limit. Mostly, green algae are found (31 species), followed by diatoms (19 species), then blue-green algae (13 species). CCA (Canonical Corresponding Analysis) indicates that green algae are strongly correlated with pH, NH4, alkalinity, Mn and Si; diatoms with EC (electric conductivity), turbidity, Zn and Si and blue green algae with EC and alkalinity. 50% of samples of surface origin, 80% of samples of both deep and shallow groundwater origins crossed WHO and Egyptian guideline in their content of mean TCC (Total Coliform Count). CCA estimates strong correlations of TCC with temperature, NH4 and PO4; E. coli with EC; heterotrophic bacteria with turbidity and NO3; Salmonella sp. with Si and SO4 and Pseudomonas aeruginosa with Mn. Finally, the water plants treatment may be not effective and pipes serve as a reservoir for pathogenic microorganisms. 展开更多
关键词 Water pollution drinking water physicochemical characteristics ALGAE bacteria.
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2000年以来福建省区域经济差异时空演化 被引量:4
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作者 张明发 王强 《福建师范大学学报(自然科学版)》 CAS CSCD 北大核心 2016年第3期124-133,共10页
以人均GDP为测度指标,采用二阶段嵌套锡尔系数分解方法,从地级和县域两种尺度对2000-2013年福建省区域经济差异进行分解测度和比较研究.同时利用ESDA空间统计分析,从县域尺度揭示区域经济差异空间格局演变趋势.研究结果表明:福建省区域... 以人均GDP为测度指标,采用二阶段嵌套锡尔系数分解方法,从地级和县域两种尺度对2000-2013年福建省区域经济差异进行分解测度和比较研究.同时利用ESDA空间统计分析,从县域尺度揭示区域经济差异空间格局演变趋势.研究结果表明:福建省区域经济总体差异表现出先扩大后缩小的"倒U型"结构特征.地市内差异对于全省总体差异的影响较地区间和地市间差异显著.福建省经济空间格局呈现出明显空间集聚态势,集聚程度不断加强.经济热点区呈现出由"强-中-弱三核"—"V"字型—"双核"的格局演化特征;经济增长空间格局则呈现出"先强集聚后弱集聚"的空间集聚特征.经济增长热点区展现出由单核—三核增长的空间演化特征. 展开更多
关键词 锡尔系数 县域 总体差分解 经济空间格局 福建
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