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TDICCD相机的低噪声视频处理技术

光学精密工程 2008年第10期16卷 1869-1873页

作者：郝贤鹏任建岳中国科学院长春光学精密机械与物理研究所中国科学院研究生院

建立了TDICCD相机系统的噪声模型,分析了TDICCD视频信号读出复位噪声的产生机理,讨论了相关双采样技术的工作原理;给出了TDICCD相机视频处理电路各个组成部分的设计,并进行了分析。在此基础上设计了科学级TDICCD相机。实验结果表明,该... 详细信息

建立了TDICCD相机系统的噪声模型,分析了TDICCD视频信号读出复位噪声的产生机理,讨论了相关双采样技术的工作原理;给出了TDICCD相机视频处理电路各个组成部分的设计,并进行了分析。在此基础上设计了科学级TDICCD相机。实验结果表明,该视频处理电路在本身引入噪声较小的同时,有效地抑制了暗电流噪声、复位噪声、1/f噪声等,数据输出速率在55 MHz时,整机信噪比(S/N)在50 dB以上。

关键词： TDICCD相机低噪声相关双采样视频处理

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弹性支承块轨道结构落轴冲击动力性能分析

中国铁道科学 2006年第3期27卷 22-26页

作者：朱剑月练松良同济大学道路与交通工程教育部重点实验室

将轮轨接触边界条件用罚函数法释放,采用点面接触单元导出轮轨接触有限元控制方程,建立轨道结构落轴冲击动力有限元方程。分析落轴冲击对轨道结构产生的动态响应,比较弹性支承块及短轨枕埋入式整体道床轨道结构的动力性能,并用现场实测... 详细信息

将轮轨接触边界条件用罚函数法释放,采用点面接触单元导出轮轨接触有限元控制方程,建立轨道结构落轴冲击动力有限元方程。分析落轴冲击对轨道结构产生的动态响应,比较弹性支承块及短轨枕埋入式整体道床轨道结构的动力性能,并用现场实测数据进行验证。结果表明:弹性支承块轨道结构与普通短轨枕结构相比,其轨下及块下刚度易于调整,可进行双层弹性的合理匹配,从而有效吸收轮轨冲击,提高列车运行平稳性,具有减振降噪与延缓轮轨磨损等优越性能。建议其块下刚度稍大于轨下刚度,增幅值控制在20%以内。

关键词：轨道结构弹性支承块有限元落轴冲击动态响应

壁面厚度随机度对闭孔Voronoi泡沫材料弹性性能的影响

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航空动力学报 2010年第3期25卷 592-596页

作者：卢子兴王建月北京航空航天大学航空科学与工程学院北京100191

基于闭孔Voronoi随机模型,通过引入壁面厚度随机度,研究了壁面厚度不均匀性对各向同性和各向异性闭孔泡沫弹性性能的影响,并讨论了壁面厚度随机度与模型随机度共同作用下的影响效果.结果表明,壁面厚度随机度对各向同性和各向异性弹性模... 详细信息

基于闭孔Voronoi随机模型,通过引入壁面厚度随机度,研究了壁面厚度不均匀性对各向同性和各向异性闭孔泡沫弹性性能的影响,并讨论了壁面厚度随机度与模型随机度共同作用下的影响效果.结果表明,壁面厚度随机度对各向同性和各向异性弹性模量均起减小的作用,且其在各向同性时的影响效果要低于模型随机度的影响,而在各向异性情况下则要高于模型随机度的影响.但是,壁面厚度随机度对闭孔泡沫的泊松比影响却很小.

关键词：闭孔泡沫弹性性能 Voronoi模型擘面厚度随机度各向异性

Performance Evaluation of a Self-Developed Ozonesonde and Its Application in an Intensive Observational Campaign

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Atmospheric and Oceanic Science Letters 2014年第3期7卷 175-179页

作者： ZHANG Jin-Qiang XUAN yue-jian XIA Xiang-Ao LIU Ming-Yuan YAN Xiao-Lu PANG Li BAI Zhi-Xuan WAN Xiao-Wei Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Chinese Academy of Meteorological Sciences jiangsu Radio Scientific Institute Company Limited

To make a detailed test on the reliability and detection performance of the electrochemical concentra- tion cell （ECC） type ozonesonde which had been devel- oped and preliminarily evaluated by the authors, an inten- sive ozonesonde release experiment was held at two sites in Beijing and Changchun in June 2013. The results showed that the mean background current and its standard deviation were 0.03 （0.04） pA and 0.02 （0.03） pA in Bei- jing （Changchun）. The average response time and its standard deviation were 27.8 s （30.4 s） and 4.0 s （3.7 s） in Beijing （Changchun）. The ozone partial pressure profiles at both sites showed a central peak in the stratosphere and a side peak in the boundary layer. Large variation in ozone partial pressure was observed at the middle levels of the atmosphere （10-17 kin）. A more marked gradient of ozone change was observed in Beijing （3.4 mPa km-1） at the lower atmosphere level, as compared to that in Changchun （0.4 mPa km-l）. The results presented in this paper indicate that this self-developed ozonesonde shows a high level of reliability and good performance. The ozonsonde is expected to play an important role in opera- tional observations of ozone profiles.

关键词： ozonesonde evaluationozone profile

开孔Voronoi泡沫支柱形状变化对力学性能的影响

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航空动力学报 2009年第9期24卷 2007-2011页

作者：卢子兴王建月北京航空航天大学航空科学与工程学院北京100191

针对开孔泡沫材料提出了新的支柱形状控制方程,并在Voronoi随机泡沫模型基础上,研究了支柱形状变化对其各向同性弹性性能、非线性压缩和拉伸力学行为的影响;讨论了支柱细腰程度和模型随机度共同作用的影响效果,并比较了两种因素作用效... 详细信息

针对开孔泡沫材料提出了新的支柱形状控制方程,并在Voronoi随机泡沫模型基础上,研究了支柱形状变化对其各向同性弹性性能、非线性压缩和拉伸力学行为的影响;讨论了支柱细腰程度和模型随机度共同作用的影响效果,并比较了两种因素作用效果的大小.结果表明,支柱细腰程度的增大明显降低了泡沫材料的弹性模量和无量纲应力.同时,支柱细腰程度对泡沫力学性能的影响要大于模型随机度的影响,并随模型随机度的增加而增大.

关键词：泡沫材料力学性能 Voronoi模型支柱形状

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软土地基中组合桩承载性状试验研究

四川大学学报（工程科学版） 2008年第3期40卷 65-69页

作者：岳建伟白宪臣谷岩河南大学材料与结构研究所河南开封475001 天津大学建筑工程学院天津300072

为掌握组合桩(钢筋混凝土桩插入水泥土搅拌桩复合而成的桩)的荷载传递机理、破坏模式和竖向承载力特性,通过对3根14 m长桩的载荷试验和桩身应变的测量,分析了桩身轴力的分布和桩周的侧摩阻力分布及影响组合桩承载力因素。试验得到了组... 详细信息

为掌握组合桩(钢筋混凝土桩插入水泥土搅拌桩复合而成的桩)的荷载传递机理、破坏模式和竖向承载力特性,通过对3根14 m长桩的载荷试验和桩身应变的测量,分析了桩身轴力的分布和桩周的侧摩阻力分布及影响组合桩承载力因素。试验得到了组合桩的Q-S曲线、S-logt曲线、桩的极限承载力;试验表明混凝土桩的插入改变竖向荷载的传递规律,形成了从混凝土桩到水泥土再到土的传递模式,更有效地发挥了桩周的侧摩阻力;水泥土的固化效应、混凝土桩的挤土效应和混凝土桩的荷载传递是组合桩高承载力的主要来源。组合桩具有较高的单桩竖向承载力且造价低,在软土地基工程中具有广泛的应用价值。

关键词：水泥土搅拌桩软土组合桩预应力混凝土桩挤土效应

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轨道结构落轴冲击动态响应有限元分析

铁道学报 2005年第3期27卷 76-79页

作者：朱剑月练松良同济大学道路与交通工程教育部重点实验室上海200331

通过确定落轴冲击问题的轮轨接触条件,根据接触冲击响应的虚位移原理,将轮轨接触边界条件用罚函数法释放,确立轮轨接触变分方程;采用点面接触单元导出轮轨接触有限元控制方程,进一步建立轨道结构动力有限元方程,从而可模拟计算落轴冲击... 详细信息

通过确定落轴冲击问题的轮轨接触条件,根据接触冲击响应的虚位移原理,将轮轨接触边界条件用罚函数法释放,确立轮轨接触变分方程;采用点面接触单元导出轮轨接触有限元控制方程,进一步建立轨道结构动力有限元方程,从而可模拟计算落轴冲击对轨道结构产生的动态响应。基于该分析方法,求解了弹性支承块轨道结构的动力性能,并由现场实测得到验证。结果表明,运用所建立的落轴冲击有限元计算模型分析轨道结构动力性能,直观有效。

关键词：轨道结构有限元落轴冲击动态响应

Diagnosis and endovascular treatment of spontaneous direct carotid-cavernous fistula

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Chinese Medical Journal 2008年第16期121卷 1558-1562页

作者： YU Jia-sheng LEI Ting CHEN Jin-cao HE yue CHEN jian LI Ling Department of Neurosurgery Tongj1 Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Huhei 430030 China

Background Spontaneous direct carotid-cavernous fistula （CCF） is relatively rare and few reports have been found in the literature. The aim of this paper was to report the clinical characteristics, imaging findings and curative effect of endovascular treatment for patients with spontaneous direct CCF. Methods We retrospectively analyzed the clinical data of nine patients with spontaneous direct CCF admitted between May 2003 and November 2007 and the *** endovascular treatment. Sudden neuro-ophthalmological symptoms were the most common clinical presentation at diagnosis （n=8）. No patients had a history of head trauma. Cerebral digital subtraction angiography （DSA） was performed on all cases under local anesthesia and seven cases received endovascular treatment. Results In eight patients, internal carotid angiograms recorded during the early arterial phase revealed aneurysms located in the cavernous sinuses, and in one patient, a dilated internal carotid artery （ICA） was seen. Among the nine cases, seven received endovascular treatment via a transarterial approach and complete occlusion of the fistula was obtained with no technique-related complications, one died suddenly before treatment and one gave up treatment. A detachable balloon was used as the embolic material in two cases, a detachable balloon and detachable coil as the embolic material in two cases, balloon-assisted coil embolization in two cases and covered stents were successfully placed in the parent vessel to exclude the aneurysm and fistula from circulation in one case. During a follow-up period of 3-48 months, all treated patients remained asymptomatic except for one patient who suffered from ipsilateral decreased vision. Conclusions Most spontaneous direct CCF may be caused by a ruptured intracavernous aneurysm with direct shunting into the cavernous sinus. Endovascular treatment seems to be a safe and effective method for treating spontaneous direct CCF.

关键词： spontaneous, direct, carotid-cavernous fistula detachable balloon coil covered stent

Polymorphisms of MTHFR and TYMS predict capecitabine-induced hand-foot syndrome in patients with metastatic breast cancer

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Cancer Communications 2019年第1期39卷 514-525页

作者： Shaoyan Lin jian yue Xiuwen Guan Peng Yuan Jiayu Wang Yang Luo Ying Fan Ruigang Cai Qiao Li Shanshan Chen Pin Zhang Qing Li Fei Ma Binghe Xu Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeNo.17Panjiayuan NanliChaoyang DistrictBeijing 100021P.R.China Department of VIP Medical Services National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100021P.R.China

Background:Breast cancer is a global problem,and a large number of new cases are diagnosed every ***-abine is effective in patients with metastatic breast cancer(MBC).Hand-foot syndrome(HFS)is a common adverse effect of *** this study,we investigated the association between single nucleotide polymorphisms(SNPs)in genes involved in capecitabine metabolism pathways and capecitabine-induced HFS in Chinese patients with MBC to identify some predictive genetic ***:We selected 3 genes involved in capecitabine metabolism and screened genetic variants in these target *** genotyped a total of 22 SNPs in the thymidylate synthase gene(TYMS),the methylene tetrahydrofolate reductase gene(MTHFR),and the ribonucleotide reductase M1 gene(RRM1)in 342 MBC patients treated with capecit-abine-based *** genotype distributions of each SNP in patients with and without HFS were assessed using Pearson’sχ^(2)test,and the relationship between HFS and genotypes of SNPs was determined using logistic regression *** association between SNPs and their corresponding gene expression was analyzed using the Blood expression quantitative trait loci(eQTL)browser online ***:We found 4 positive sites for HFS in the TYMS and MTHFR genes:TYMS rs2606241(P=0.022),TYMS rs2853741(P=0.019),MTHFR rs3737964(P=0.029),and MTHFR rs4846048(P=0.030).Logistic regression analyses showed that the genotype AG of MTHFR rs3737964[odds ratio(OR)=0.54,95%confidence interval(CI)0.31-0.97,P=0.038]and MTHFR rs4846048(OR=0.54,95%CI 0.30-0.98,P=0.042)were protective factors of HFS,whereas the genotype CT of TYMS rs2853741(OR=2.25,95%CI 1.31-3.87,P=0.012)increased the risk of *** association between the genotype GT of TYMS rs2606241(OR=1.27,95%CI 0.73-2.23,P=0.012)and HFS was *** eQTL analyses confirmed that the alleles of rs3737964 and rs4846048 affected the gene expression levels of MTHFR in ***:We have identified four potentiall

关键词： Capecitabine Polymorphism Metastatic breast cancer Hand-foot syndrome TYMS MTHFR