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Estimating Differences in Restricted Mean Lifetime Using Additive Hazards Models under Dependent Censoring

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 17-34页

作者： Qun LI bao-xue zhang Liu-quan SUN School of Statistics Capital University of Economics and BusinessBeijing 100070China Institute of Applied Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

In epidemiological and clinical studies,the restricted mean lifetime is often of direct interest *** differences of this quantity can be used as a basis of comparing several treatment groups with respect to their survival *** the factor of interest is not randomized and lifetimes are subject to both dependent and independent censoring,the imbalances in confounding factors need to be *** use the mixture of additive hazards model and inverse probability of censoring weighting method to estimate the differences of restricted mean *** average causal effect is then obtained by averaging the differences in fitted values based on the additive hazards *** asymptotic properties of the proposed method are also derived and simulation studies are conducted to demonstrate their finite-sample *** application to the primary biliary cirrhosis(PBC)data is illustrated.

关键词： additive hazards model dependent censoring inverse probability censoring weighting mean lifetime

A Two Sample Test based on U-statistic for Functional Data

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Acta Mathematica Sinica,English Series 2023年第3期39卷 533-552页

作者： Wen Juan HU Liang WANG bao xue zhang Guo Chang WANG School of Statistics Capital University of Economics and BusinessBeijing 100070P.R.China School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China School of Economics Jinan UniversityGuangzhou 510632P.R.China

We propose a two-sample test for the mean functions of functional data when the number of bases is much lager than the sample *** novel test is based on U-statistics which avoids estimating the covariance operator accurately under the high dimensional *** further prove the asymptotic normality of our test statistic under both null hypothesis and a local alternative *** extensive simulation study is presented which shows that the proposed test works well in comparison with several other methods under the high dimensional *** application to egg-laying trajectories of Mediterranean fruit flies data set demonstrates the applicability of the method.

关键词： Mean test functional data U-statistics two sample

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Existence,uniqueness,and global attractivity of positive solutions and MLE of the parameters to the Logistic equation with random perturbation

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Science China Mathematics 2007年第7期50卷 977-986页

作者： Da-qing JIANG bao-xue zhang De-hui WANG Ning-zhong SHI School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024China School of Mathematics Jilin UniversityChangchun 130012China

This paper discusses a randomized Logistic equation $\dot N(t) = (r + \alpha \dot B(t))N(t)[1 - \frac{{N(t)}}{K}]$ with an initial value N(0) = N 0, and N 0 is a random variable satisfying 0 < N 0 < K. The existence, uniqueness and global attractivity of positive solutions and maximum likelihood estimate (MLE) of the parameters of the equation are studied.

关键词： randomized Logistic equation existence uniqueness global attractivity MLE of the parameter 34F05 34E10 62F10

Novel MEI1 compound heterozygous mutation in a sporadic family associated with spermatogenetic failure

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Asian Journal of Andrology 2023年第4期25卷 544-546页

作者： Jie Chen Feng-Hua Li Jin-Hao Xing xue-bao zhang Zhao-Li Du Yin-Shan Jin Yuan-Qing Cui Xiong Wang Reproductive Medicine Center Affiliated Yantai Yuhuangding Hospital of Qingdao UniversityYantai 264000China Yinfeng Gene Technology Co. Ltd.Jinan 250000China

Dear Editor,Male infertility is a complex and multifactorial health problem with highly heterogeneous phenotypes,ranging from reduced sperm production to the complete absence of sperm in testis,and genetic factors play an important role in this problem.1 Patients with azoospermia have the highest risk of carrying genetic abnormalities,and this risk gradually decreases as sperm count increases.1 Due to the high throughput and low cost of next-generation sequencing(NGS)technology,many centers have used NGS to identify genetic defects associated with abnormal spermatogenesis.

关键词： centers compound infertility

Synergistic Effect of Schwann Cells and Retinoic Acid on Differentiation and Synaptogenesis of Hippocampal Neural Stem Cells in vitro

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Biomedical and Environmental Sciences 2006年第3期19卷 219-224页

作者： xue-bao zhang YUAN-SHAN ZENG WEI zhang YA-YUN CHEN YI XIONG SUI-JUN CHEN Division of Neuroscience Department of Histology and Embryology Zhongshan Medical College Sun Yat-Sen University Guangzhou 510080 Guangdong China

Objective To investigate the synergistic effect of Schwann cells （SCs） and retinoic acid （R.A） on differentiation and synaptogenesis of neural stem cells （NSCs） derived from hippocampus of neonatal rats. Methods The classical method for 2×2 factorial analysis experiment was used to assess synergistic action of SCs and RA. NSCs were treated with R.A, SCs, and SCs ＋ RA in DMEM/F12 with 0.5% fetal bovine serum for six days, respectively. Double immunofluorescent staining was used to detect the differentiation of NSCs including nestin, glial fibrillary acidic protein （GFAP） and Map2. The expression of PSD95 was used to demonstrate synaptogenesis. Results After NSCs were treated with RA or SCs, the expression of nestin and GFAP was significantly decreased while the expression of Map2 and PSD95 was significantly increased in comparison with the control. Factorial ANOVA showed that interactions between SCs and RA could induce the expression of Map2 and PSD95. Conclusion SCs and RA could promote synergistically the neuronal differentiation and synaptogenesis of hippocampal neural stem cells in vitro while they decreased the astrocytes and nestin positive NSCs.

关键词： Neural stem cell Neuronal differentiation PSD95 Schwann cells Retinoic acid

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综合聚类和上下文特征的高光谱影像分类

武汉大学学报（信息科学版） 2017年第7期42卷 890-896页

作者：鲍蕊薛朝辉张像源苏红军杜培军天津市地质调查研究院天津300191 南京大学卫星测绘技术与应用国家测绘地理信息局重点实验室江苏南京210023 南京大学江苏省地理信息技术重点实验室江苏南京210023 河海大学地球科学与工程学院江苏南京210098

常规高光谱影像逐像素分类往往没有考虑空间相关性,分类结果未体现地物的空间关联和分布特征。为了在分类中充分利用空间特征,利用聚类信息并结合隐马尔可夫随机场模型讨论了高光谱遥感影像光谱-空间分类方法。首先,在不同特征提取方法... 详细信息

常规高光谱影像逐像素分类往往没有考虑空间相关性,分类结果未体现地物的空间关联和分布特征。为了在分类中充分利用空间特征,利用聚类信息并结合隐马尔可夫随机场模型讨论了高光谱遥感影像光谱-空间分类方法。首先,在不同特征提取方法(最小噪声分离、独立成分分析和主成分分析)下,使用不同聚类方法(k-均值、迭代自组织分析算法和模糊c-均值算法)借助隐马尔可夫随机场获取优化的分割图;然后,采用4连通区域标记法对分割区域标记生成图像对象,并根据支持向量机的逐像素分类结果采用多数投票法对图像对象进行分类;最后,借助凹槽窗口邻域滤波技术改进分类结果,削弱"椒盐"现象。该方法综合了监督分类和非监督分类的优势,通过聚类引入地物空间相关性信息,通过隐马尔可夫随机场引入上下文特征,较好地弥补了单纯基于光谱信息分类的不足。

关键词：聚类隐马尔可夫随机场支持向量机高光谱影像光谱-空间分类多数投票

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功率因数校正电路设计

安徽电子信息职业技术学院学报 2006年第5期5卷 72-74,81页

作者：薛宝章中国电子科技集团41研究所安徽蚌埠233000

本文主要介绍功率因数校正的概念以及有源功率因数校正电路的基本原理和设计方法。

关键词：功率因数校正平均电流控制模式升压式变换器

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改进的密封铅酸蓄电池充电技术

安徽电子信息职业技术学院学报 2006年第3期5卷 85-87页

作者：薛宝章中国电子科技集团第41研究所安徽蚌埠233000

对于密封铅酸蓄电池,我们使用的传统充电电路是恒压限流充电电路。本文介绍了一种先进的密封铅酸蓄电池充电电路的设计原理,给出了确定充电参数的方法和基本公式。和传统电路相比,这种电路的优点是能使电池快速充电,恢复到最大容量,且... 详细信息

对于密封铅酸蓄电池,我们使用的传统充电电路是恒压限流充电电路。本文介绍了一种先进的密封铅酸蓄电池充电电路的设计原理,给出了确定充电参数的方法和基本公式。和传统电路相比,这种电路的优点是能使电池快速充电,恢复到最大容量,且能延长电池的使用寿命。

关键词：密封铅酸蓄电池充电器均充电过充电浮充电

基于M-CVaR的供应链收益共享契约协调研究

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运筹与管理 2016年第6期25卷 53-58页

作者：钟昌宝丁彦学张宏如常州大学商学院江苏常州213164

基于收益共享契约能有效改善供应链运作效率且实践中不仅存在风险中性、厌恶型,还存在风险喜好型供应链成员。运用均值-条件风险价值统一度量决策者的风险喜好、中性及厌恶水平,并据此研究考虑决策者风险偏好水平的供应链收益共享契约... 详细信息

基于收益共享契约能有效改善供应链运作效率且实践中不仅存在风险中性、厌恶型,还存在风险喜好型供应链成员。运用均值-条件风险价值统一度量决策者的风险喜好、中性及厌恶水平,并据此研究考虑决策者风险偏好水平的供应链收益共享契约协调问题。首先建立零售商及供应链整体的均值-条件风险价值模型;然后研究考虑决策者风险偏好水平的供应链收益共享契约协调问题;最后讨论供应链成员的风险偏好水平对最优订购量及最优批发价格的影响,并通过数值算例进行验证。结果表明产品的最优批发价格随着零售商悲观系数的增大而减小,随着供应商悲观系数的增大而增大,而最优订购量随着零售商悲观系数的增大而减小,亦随着供应商悲观系数的增大而减小。因此,设计供应链收益共享契约时应考虑成员的风险偏好水平。

关键词：均值-条件风险价值收益共享契约供应链协调