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Generation of Accelerated Stability Experiment Profile of Inertial Platform Based on Finite Element

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Chinese Journal of Aeronautics 2012年第4期25卷 584-592页

作者： CHEN Yunxia huang xiaokai KANG Rui School of Reliability and System Engineering Beihang UniversityBeijing 100191China

The residual stress generated in the manufacturing process of inertial platform causes the drift of inertial platform parameters in long-term storage ***,the existing temperature cycling experiment could not meet the increased repeatability technical requirements of inertial platform *** order to solve this problem,in this paper,firstly the Unigraphics（UG） software and the interface compatibility of ANSYS software are used to establish the inertial platform finite element ***,the residual stress is loaded into finite element model by ANSYS function editor in the form of surface loads to analyze the *** then,the generation based on ANSYS simulation inertial platform to accelerate the stability of experiment profile is achieved by the application of the analysis method of orthogonal experimental design and ANSYS thermal-structural *** optimum accelerated stability experiment profile is determined finally,which realizes the rapid,effective release of inertial platform residual *** research methodology and conclusion of this paper have great theoretical and practical significance to the production technology of inertial platform.

关键词： inertial platform residual stresses accelerated stability orthogonal experimental design ANSYS thermal-structural coupled analysis

Associations between LMO1 gene polymorphisms and central nervous system tumor susceptibility

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Pediatric Investigation 2021年第4期5卷 281-287页

作者： Huiran Lin Huitong Chen Ao Lin Xiaoping Liu xiaokai huang Jingying Zhou Li Yuan Zhenjian Zhuo Department of Pediatric Surgery Guangzhou Institute of PediatricsGuangdong Provincial Key Laboratory of Research in Structural Birth Defect DiseaseGuangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhouGuangdongChina Faculty of Medicine Macao University of Science and TechnologyMacaoChina Laboratory Animal Management Office Public Technology Service PlatformShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdongChina Department of Hematology Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhouGuangdongChina Department of Hematology The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhouZhejiangChina Department of Pathology Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhouGuangdongChina

Importance:LIM domain only 1(LMO1)gene polymorphisms were previously found to be implicated in the risk of several *** available studies were performed regarding the predisposing effect of LMO1 gene single nucleotide polymorphisms(SNPs)on central nervous system(CNS)tumor ***:We aimed to determine whether the LMO1 gene SNPs were associated with the risk of CNS tumor by applying a case-control study with 191 cases and 248 controls in ***:The contributions of LMO1 gene SNPs to the risk of CNS tumor was evaluated by multinomial logistic ***:Based on the calculations of odds ratio(OR)and 95%confidence interval(CI),we failed to detect a significant relationship between each LMO1 gene SNP(rs110419 A>G,rs4758051 G>A,rs10840002 A>G,rs204938 A>G,and rs2168101 G>T)and CNS tumor risk,respectively.A negative association was also found in the combined effects on these five SNPs and CNS tumor *** stratification analysis further demonstrated the individuals with rs204938 AG/GG genotype confer to increased risk of CNS tumor compared with those with an AA genotype in males(OR:1.74,95%CI:1.01-2.98,P=0.046).Interpretation:We concluded that LMO1 gene SNPs may not strong enough to influence the risk of CNS tumor in Chinese *** studies are required to verify this association.

关键词： LMO1 SNPs CNS tumor Chinese

Association of ERCC1 and XPF polymorphisms with pediatric glioma susceptibility

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Chinese Medical Journal 2023年第6期136卷 746-748页

作者： Yongping Chen Yuxiang Liao Xingyu Jia Huiran Lin Lei Miao Li Yuan xiaokai huang Jingying Zhou Jun Bian Zhenjian Zhuo Department of Pediatric Surgery Guangzhou Institute of PediatricsGuangdong Provincial Key Laboratory of Research in Structural Birth Defect DiseaseGuangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhouGuangdong 510623China Department of Neurosurgery Xiangya HospitalCentral South UniversityChangshaHunan 410008China School of Medicine Jinan UniversityGuangzhouGuangdong 510632China Faculty of Medicine Macao University of Science and TechnologyMacao 999078China Department of Hematology The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical UniversityWenzhouZhejiang 325027China Department of General Surgery Xi’an Children’s HospitalXi’an Jiaotong University Affiliated Children’s HospitalXi’anShaanxi 710003China Laboratory Animal Center School of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhenGuangdong 518055China

To the Editor:Glioma is a highly invasive and lethal heterogeneous disease caused by glial or precursor cell *** accounts for about 50%of tumors in children and 80%of malignant tumors.[1]The nucleotide excision repair(NER)pathway is a process that involves the sequential assembly of many proteins,including excision repair cross complementation group 1(ERCC1)and xeroderma pigmentosum complementation group F(XPF,also known as ERCC4).

关键词： ERCC1 XPF excision

Uniqueness of the Reissner-Nordstrom metric near the null infinity

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Science China Mathematics 2024年第8期67卷 1933-1956页

作者： xiaokai He Xiaoning Wu Naqing Xie School of Mathematics and Statistics Hunan First Normal UniversityChangsha 410205China Institute of Mathematics Academy of Mathematics and Systems Science and Hua Loo-Keng Key Laboratory of MathematicsChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences Fudan UniversityShanghai 200433China

In the Newman-Penrose formalism,we prove that the Reissner-Nordstrom metric is the only asymptotically fat,static,axially symmetric,Petrov type-D analytic solution of the electro-vacuum Einstein-Maxwell equations near... 详细信息

关键词： uniqueness theorem Reissner-Nordstrom metric Newman-Penrose formalism

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基于多机理竞争退化的导弹贮存可靠性分析

北京航空航天大学学报 2013年第5期39卷 701-705页

作者：罗湘勇黄小凯北京航空航天大学可靠性与系统工程学院北京100191

远程转换开关、无线电高度表、雷达角自动装置、陀螺仪和弹上电源是影响导弹长期贮存可靠性的关键部件.明确导弹贮存剖面,通过定期检测得到长期贮存条件下各关键部件的特征电压值,然后采用移动标准偏差方法描述了各特征电压值的贮存稳... 详细信息

远程转换开关、无线电高度表、雷达角自动装置、陀螺仪和弹上电源是影响导弹长期贮存可靠性的关键部件.明确导弹贮存剖面,通过定期检测得到长期贮存条件下各关键部件的特征电压值,然后采用移动标准偏差方法描述了各特征电压值的贮存稳定性水平,并对其进行退化规律拟合求得各关键部件贮存寿命.提炼出10套导弹产品的各关键部件贮存寿命,通过分布假设检验和分布参数辨识,求得各关键部件的贮存可靠度模型,最后根据导弹产品随机性、分散性、多机理竞争特点,分析导弹产品在悲观和乐观情况下的可靠性结果.本文的研究思路和结论能为长期贮存条件下贮存类产品的贮存可靠性评估、贮存维护方案研究提供技术支撑.

关键词：导弹随机性分散性多机理竞争退化贮存可靠性

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基于多应力加速试验方法的智能电表寿命评估

北京航空航天大学学报 2015年第12期41卷 2217-2224页

作者：查国清黄小凯康锐北京航空航天大学可靠性与系统工程学院北京100191 中国空间技术研究院北京卫星环境工程研究所北京100094

如何准确地分析、评估多应力-多参数下智能电表的可靠性和寿命是当前热点.首先分析了在温度、湿度、电应力、振动和磁场等条件下智能电表的性能参数内涵,通过失效机理分析提炼了关键参数及其敏感应力,然后通过强化试验探索了关键参数应... 详细信息

如何准确地分析、评估多应力-多参数下智能电表的可靠性和寿命是当前热点.首先分析了在温度、湿度、电应力、振动和磁场等条件下智能电表的性能参数内涵,通过失效机理分析提炼了关键参数及其敏感应力,然后通过强化试验探索了关键参数应力极限条件,设计了加速寿命试验方案并实施,对试验数据进行退化轨迹建模、多应力加速模型研究,综合评估了智能电表可靠性和寿命水平.本文成果能为改善智能电表可靠性和寿命提供方法.

关键词：智能电表多应力多参数强化试验加速寿命试验

Uncertainty of the Export VAT Rebate Policy:Measurement and Its Effects

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China Finance and Economic Review 2024年第2期13卷 90-111页

作者： Yanzhe Zhang Helian Xu xiaokai Shao School of Economics Hainan University School of Economics and Trade Hunan University International Business School Beijing Foreign Studies University

Based on the export VAT rebate rate data from 2004 to 2015,this paper measures the uncertainty of Chinese export VAT rebate policy by using unexpected fluctuation of export VAT rebate rate,and finds that the index varies across products,years and ***,the paper studies the influence of the uncertainty of export VAT rebate policy on China’s export growth from both theoretical and empirical *** research results show that this uncertainty reduces the expected profit of export enterprises and their optimal output,and significantly reduces the growth rate of the ordinary export that applies the export VAT rebate method,but it has no impact on the processing *** decomposing total value of exports,it is found that the growth in the number of ordinary export relationship and average sales decrease with the increase of uncertainty,while the average price growth rate increases slightly,and these effects are only refl ected in the newly entered export *** findings suggest that when the uncertainty of export VAT rebate policy is high,enterprises are more cautious about entering the ordinary export market and more likely to adopt a lowquantity-high-price strategy.

关键词： export VAT rebate policy uncertainty export growth ordinary export

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加速度计参数变化建模方法

北京航空航天大学学报 2010年第10期36卷 1229-1233页

作者：黄小凯陈云霞康锐北京航空航天大学可靠性与系统工程学院北京100191

通过归纳工程上常用数据建模方法及其应用特点,且结合贮存条件下加速度计零偏和标度因数试验测量数据变化规律,综合给出了建立零偏时间序列模型和标度因数回归模型的详细步骤,并据此建立了贮存条件下加速度计零偏和标度因数的变化模型,... 详细信息

通过归纳工程上常用数据建模方法及其应用特点,且结合贮存条件下加速度计零偏和标度因数试验测量数据变化规律,综合给出了建立零偏时间序列模型和标度因数回归模型的详细步骤,并据此建立了贮存条件下加速度计零偏和标度因数的变化模型,所建模型预测的数据与真实数据相比误差很小,充分验证了模型的有效性.所建模型真实地反映了零偏随机性变化规律和标度因数趋势性变化规律的特点,可以为加速度计零偏和标度因数随时间变化的补偿模型提供参考,为加速度计参数长期变化稳定性水平评价提供手段.

关键词：加速度计回归分析时间序列分析零偏标度因数

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长期贮存平台惯导系统壳体效应变化行为模型

北京航空航天大学学报 2016年第3期42卷 444-451页

作者：黄小凯张超胡芳刘守文北京卫星环境工程研究所北京100094 航天机电产品环境可靠性试验技术北京市重点实验室北京100094 北京航空航天大学自动化科学与电气工程学院北京100083

长期贮存条件下平台惯导系统壳体效应具有与使用状态不同的漂移特性,其漂移规律与各性能参数退化及其相互耦合特性相关,在工程应用中往往难以分析贮存条件下壳体效应稳定性水平和合理配置标定维护资源。本文通过全面分析伺服电路零位和... 详细信息

长期贮存条件下平台惯导系统壳体效应具有与使用状态不同的漂移特性,其漂移规律与各性能参数退化及其相互耦合特性相关,在工程应用中往往难以分析贮存条件下壳体效应稳定性水平和合理配置标定维护资源。本文通过全面分析伺服电路零位和框架轴上干扰力矩引起壳体效应漂移的原理及其漂移表达式,在此基础上深入挖掘了表达式中漂移参数的变化特性,综合给出了伺服电路零位和框架轴上干扰力矩引起壳体效应漂移的变化行为模型,并结合实际贮存环境剖面对其进行了长期漂移特性、加速特性和稳定性分析,分析表明在现有贮存条件下,伺服电路零位和框架轴上干扰力矩引起的壳体效应在X、Y和Z轴的长期漂移特性相近,与实际使用状态的响应特性不同,且无加速特性,具有较好的稳定性水平,从而为合理安排标定维护资源提供了依据。

关键词：长期贮存平台惯导系统壳体效应伺服电路零位干扰力矩