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SBAS-InSAR技术监测青藏高原季节性冻土形变 被引量:111
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作者 李珊珊 李志伟 +2 位作者 胡俊 孙倩 俞晓莹 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2013年第5期1476-1486,共11页
冻土的冻结和融化的反复交替会造成地质环境与结构的破坏,从而导致房屋和道路等地面工程建筑物的地基破裂或者塌陷,还会引起山体滑坡、洪水暴发以及冰川移动等.因此,监测冻土形变对确保冻土区工程建筑的稳定性和安全性,同时保证冻土区... 冻土的冻结和融化的反复交替会造成地质环境与结构的破坏,从而导致房屋和道路等地面工程建筑物的地基破裂或者塌陷,还会引起山体滑坡、洪水暴发以及冰川移动等.因此,监测冻土形变对确保冻土区工程建筑的稳定性和安全性,同时保证冻土区社会经济可持续发展具有重要的意义.目前,在冻土监测方面并没有能大面积监测冻土形变时间演化情况的有效方法,本文提出将InSAR技术中的小基线集方法(SBAS-InSAR)应用于监测冻土来获取其形变时间序列中.考虑到冻土形变呈现明显的季节性特征,本文提出利用周期形变模型来代替传统SBAS方法中的线性形变模型,从而更好地分离出高程残差和大气误差.利用ENVISAT卫星获取的21景ASAR影像图作为实验数据,采用改进的SBAS技术成功获取了青藏高原从羊八井站至当雄站铁路段冻土区的地表形变时间序列图,揭示了该冻土区从2007年到2010年的季节性形变演化情况.通过与研究地区温度变化的联合分析,发现所得到的地表形变结果与冻土的物理变化规律非常吻合,证明了SBAS-InSAR技术在冻土形变监测中具有良好的发展应用前景. 展开更多
关键词 冻土 INSAR SBAS (Small BASELINE subset) 青藏高原 形变监测
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Machine learning in materials informatics:recent applications and prospects 被引量:69
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作者 Rampi Ramprasad Rohit Batra +2 位作者 Ghanshyam Pilania Arun Mannodi-Kanakkithodi Chiho Kim 《npj Computational Materials》 SCIE EI 2017年第1期1-13,共13页
Propelled partly by the Materials Genome Initiative,and partly by the algorithmic developments and the resounding successes of data-driven efforts in other domains,informatics strategies are beginning to take shape wi... Propelled partly by the Materials Genome Initiative,and partly by the algorithmic developments and the resounding successes of data-driven efforts in other domains,informatics strategies are beginning to take shape within materials science.These approaches lead to surrogate machine learning models that enable rapid predictions based purely on past data rather than by direct experimentation or by computations/simulations in which fundamental equations are explicitly solved.Data-centric informatics methods are becoming useful to determine material properties that are hard to measure or compute using traditional methods—due to the cost,time or effort involved—but for which reliable data either already exists or can be generated for at least a subset of the critical cases.Predictions are typically interpolative,involving fingerprinting a material numerically first,and then following a mapping(established via a learning algorithm)between the fingerprint and the property of interest.Fingerprints,also referred to as“descriptors”,may be of many types and scales,as dictated by the application domain and needs.Predictions may also be extrapolative—extending into new materials spaces—provided prediction uncertainties are properly taken into account.This article attempts to provide an overview of some of the recent successful data-driven“materials informatics”strategies undertaken in the last decade,with particular emphasis on the fingerprint or descriptor choices.The review also identifies some challenges the community is facing and those that should be overcome in the near future. 展开更多
关键词 OVERCOME subset PROPERLY
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Atomization Inhalation of Terbutaline and Budesonide Efficiently Improved Immunity and Lung Function of AECOPD Patients 被引量:30
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作者 Guilan Xiong Lijun Xu Liu Wei Xiaodan Li 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2008年第4期287-291,共5页
Chronic obstructive pulmonary disease (COPD) is a syndrome of chronic progressive airflow limitation as a result of chronic inflammation of the airways and lung parenchyma. COPD patients always have airway hyperreac... Chronic obstructive pulmonary disease (COPD) is a syndrome of chronic progressive airflow limitation as a result of chronic inflammation of the airways and lung parenchyma. COPD patients always have airway hyperreactivity (AHR), so how to reduce AHR becomes the key purpose of clinical treatment. It is hypothesized that combined inhalation of corticosteroids and β2-agonists can reduce the AHR in COPD. In this study, atomization inhalation of budesonide and terbutaline plus conventional therapies was applied to treat AECOPD (acute exacerbation of chronic obstructive pulmonary disease) patients for two weeks. The results showed that additional inhalation of budesonide and terbutaline could upregulate serum IL-2 levels, the percentages of CD3^+ T and CD4^+ T cells, and CD4/CD8 ratio, and decrease eosinophils and serum CRP level more efficiently than conventional treatment in patients with AECOPD. And the lung function of the atomization inhalation group was improved more obviously after the treatment compared with the conventional treatment group. Thus, atomization inhalation of terbutaline and budesonide can control AECOPD effectively, and has wide clinical perspective in controlling and preventing the exacerbation of COPD. Cellular & Molecular Immunology. 2008;5(4):287-291. 展开更多
关键词 AECOPD T lymphocyte subset IL-2 EOSINOPHIL C-reactive protein
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Deep learning in optical metrology:a review 被引量:25
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作者 Chao Zuo Jiaming Qian +6 位作者 Shijie Feng Wei Yin Yixuan Li Pengfei Fan Jing Han Kemao Qian Qian Chen 《Light(Science & Applications)》 SCIE EI CAS CSCD 2022年第4期466-519,共54页
With the advances in scientific foundations and technological implementations,optical metrology has become versatile problem-solving backbones in manufacturing,fundamental research,and engineering applications,such as... With the advances in scientific foundations and technological implementations,optical metrology has become versatile problem-solving backbones in manufacturing,fundamental research,and engineering applications,such as quality control,nondestructive testing,experimental mechanics,and biomedicine.In recent years,deep learning,a subfield of machine learning,is emerging as a powerful tool to address problems by learning from data,largely driven by the availability of massive datasets,enhanced computational power,fast data storage,and novel training algorithms for the deep neural network.It is currently promoting increased interests and gaining extensive attention for its utilization in the field of optical metrology.Unlike the traditional,,physics-basedH approach,deep-learning-enabled optical metrology is a kind of,/data-drivenw approach,which has already provided numerous alternative solutions to many challenging problems in this field with better performances.In this review,we present an overview of the current status and the latest progress of deep-learning technologies in the field of optical metrology.We first briefly introduce both traditional image-processing algorithms in optical metrology and the basic concepts of deep learning,followed by a comprehensive review of its applications in various optical metrology tasks,such as fringe denoising,phase retrieval,phase unwrapping,subset correlation,and error compensation.The open challenges faced by the current deep-learning approach in optical metrology are then discussed.Finally,the directions for future research are outlined. 展开更多
关键词 BACKBONE subset VERSATILE
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益气养阴活血化痰方对老年性COPD稳定期免疫功能的影响 被引量:14
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作者 李成海 邹国林 《上海中医药杂志》 北大核心 2001年第12期15-17,共3页
为探讨益气养阴活血化痰方对COPD稳定期免疫功能的影响 ,以益气养阴活血化痰方治疗 33例老年性COPD患者 ,疗程 6个月。测定患者用药前及用药 3个月、6个月的T细胞亚群、免疫球蛋白、细胞因子 ,并与 30例正常组比较。结果 :COPD患者用药... 为探讨益气养阴活血化痰方对COPD稳定期免疫功能的影响 ,以益气养阴活血化痰方治疗 33例老年性COPD患者 ,疗程 6个月。测定患者用药前及用药 3个月、6个月的T细胞亚群、免疫球蛋白、细胞因子 ,并与 30例正常组比较。结果 :COPD患者用药前CD3 +、CD4+、CD4+/CD8+、IgG、IgA、IgM、IL 2明显低于正常组 ;CD8+、TNF α高于正常组。用药 3个月、6个月后上述各项指标均有接近正常组的趋势。提示益气养阴活血化痰方能增强老年性COPD患者免疫功能的作用。 展开更多
关键词 慢性阻塞性肺部疾病 益气养阴活血化痰方 T细胞亚群 免疫球蛋白 白细胞介素-2 肿瘤坏死因子
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Anti-cd TCR antibody-expanded cd T cells:a better choice for the adoptive immunotherapy of lymphoid malignancies 被引量:18
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作者 Jianhua Zhou Ning Kang +2 位作者 Lianxian Cui Denian Ba Wei He 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2012年第1期34-44,共11页
Cell-based immunotherapy for lymphoid malignancies has gained increasing attention as patients develop resistance to conventional treatments.cd T cells,which have major histocompatibility complex(MHC)-unrestricted lyt... Cell-based immunotherapy for lymphoid malignancies has gained increasing attention as patients develop resistance to conventional treatments.cd T cells,which have major histocompatibility complex(MHC)-unrestricted lytic activity,have become a promising candidate population for adoptive cell transfer therapy.We previously established a stable condition for expanding cd T cells by using anti-cd T-cell receptor(TCR)antibody.In this study,we found that adoptive transfer of the expanded cd T cells to Daudi lymphoma-bearing nude mice significantly prolonged the survival time of the mice and improved their living status.We further investigated the characteristics of these antibody-expanded cd T cells compared to the more commonly used phosphoantigen-expanded cd T cells and evaluated the feasibility of employing them in the treatment of lymphoid malignancies.Slow but sustained proliferation of human peripheral blood cd T cells was observed upon stimulation with anti-cd TCR antibody.Compared to phosphoantigen-stimulated cd T cells,the antibody-expanded cells manifested similar functional phenotypes and cytotoxic activity towards lymphoma cell lines.It is noteworthy that the anti-cd TCR antibody could expand both the Vd1 and Vd2 subsets of cd T cells.The in vitro-expanded Vd1 T cells displayed comparable tumour cell-killing activity to Vd2 T cells.Importantly,owing to higher C–C chemokine receptor 4(CCR4)and CCR8 expression,the Vd1 T cells were more prone to infiltrate CCL17-or CCL22-expressing lymphomas than the Vd2 T cells.Characterizing the peripheral blood cd T cells from lymphoma patients further confirmed that the anti-cd TCR antibody-expanded cd T cells could be a more efficacious choice for the treatment of lymphoid malignancies than phosphoantigen-expanded cd T cells. 展开更多
关键词 adoptive cell therapy anti-cd TCR antibody cd T cells lymphoid malignancies Vd1 subset
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环磷酰胺单次注射对小鼠淋巴细胞及其亚群的早期作用 被引量:17
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作者 刘继彦 李永强 +6 位作者 彭瑞清 丁娅 李鸿立 程霞 张念华 张晓实 曾益新 《中国肿瘤生物治疗杂志》 CAS CSCD 2005年第3期179-182,共4页
目的:探讨环磷酰胺(CTX)的免疫增强作用机理。方法:对单次腹腔注射50 mg/kg CTX后小鼠外周血和脾脏中淋巴细胞数量的变化进行了连续的观察,并用流式细胞术分析了注射CTX后第5天外周血淋巴细胞亚群的变化。结果:使用CTX后第1-5天外周血... 目的:探讨环磷酰胺(CTX)的免疫增强作用机理。方法:对单次腹腔注射50 mg/kg CTX后小鼠外周血和脾脏中淋巴细胞数量的变化进行了连续的观察,并用流式细胞术分析了注射CTX后第5天外周血淋巴细胞亚群的变化。结果:使用CTX后第1-5天外周血和脾脏中淋巴细胞数量出现了迅速的下降,同时,外周血淋巴细胞亚群中出现非T淋巴细胞比例的下降和T淋巴细胞比例的升高,且CD8+比CD4+T淋巴细胞比例升高明显。结论:淋巴细胞数量和亚群的变化可能同CTX 的免疫增强作用有关。 展开更多
关键词 环磷酰胺 免疫增强作用 淋巴细胞 亚群
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基于短基线集方法(SBAS-INSAR)技术的山区城市地面沉降监测研究——以攀枝花为例 被引量:17
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作者 孟庆凯 汪宝存 苗放 《科学技术与工程》 北大核心 2016年第13期12-17,共6页
基于合成孔径雷达干涉(interferometric synthetic aperture radar,INSAR)技术的山区城市地面沉降研究,因地形复杂、植被覆盖等因素开展较少。首次在攀枝花市,利用12景2009-2010ENVISAT ASAR数据,采用短基线集方法开展大范围、长时间监... 基于合成孔径雷达干涉(interferometric synthetic aperture radar,INSAR)技术的山区城市地面沉降研究,因地形复杂、植被覆盖等因素开展较少。首次在攀枝花市,利用12景2009-2010ENVISAT ASAR数据,采用短基线集方法开展大范围、长时间监测。结果表明,攀枝花市东区地面沉降较大,沉降的平均速率高达48 mm/年;西区沉降较小,沉降平均速率10 mm/年。推测原因多为城市化建设所致地面荷载;而市东北方向的露天矿区,因连续开采所致,不同时期同一地点的地表变化,导致高相干点在此区域分散稀疏,不能表明是否有沉降现象。 展开更多
关键词 地面沉降 短基线集(sinall BASELINE subset SBAS) 时序分析 攀枝花
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大肠癌患者外周血T细胞亚群和NK细胞活性检测的临床意义 被引量:13
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作者 熊彪 邹尤宝 《国际检验医学杂志》 CAS 2008年第10期892-893,共2页
目的通过外周血 T 细胞亚群和 NK 细胞活性的检测,研究大肠癌患者免疫状况及其与肿瘤分期的关系。方法应用流式细胞术对90例大肠癌患者和40例健康成人的外周血进行 T 细胞业群和 NK 细胞活性的检测。结果大肠癌患者 CD3^+、CD4^+比例、C... 目的通过外周血 T 细胞亚群和 NK 细胞活性的检测,研究大肠癌患者免疫状况及其与肿瘤分期的关系。方法应用流式细胞术对90例大肠癌患者和40例健康成人的外周血进行 T 细胞业群和 NK 细胞活性的检测。结果大肠癌患者 CD3^+、CD4^+比例、CD4^+/CD8^+比值下降且 NK细胞活性显著降低,CD8^+比例显著高于健康对照组,随着 Dukes 分级的增加这种变化更加显著。结论大肠癌患者存在细胞免疫功能紊乱,并随病情进展而加重。 展开更多
关键词 结直肠肿瘤 T淋巴细胞亚群 杀伤细胞 天然
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Distribution of natural killer cells and T-lymphocyte subsets in peripheral blood,gallbladder cancer and surrounding tissue 被引量:12
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作者 Liu, Gang Ren, Hong +1 位作者 Sun, Xue-Jun Shi, Jing-Sen 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第1期81-86,共6页
BACKGROUND: The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to define t... BACKGROUND: The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to define the relationship between the immune function of local cells and cancer development by investigating the distribution of natural killer (NK) cells and T-lymphocyte subsets in peripheral blood, the cancer tissue and the tissue surrounding gallbladder carcinoma. METHODS: The numbers of CD4(+) and CD8(+) T-lymphocytes and NK cells were measured by flow cytometry in samples taken from gallbladder cancer tissue, the surrounding tissues and peripheral blood of 38 patients, and compared with the numbers in the peripheral blood and gallbladder tissue of 30 patients with cholecystitis as controls. RESULTS: The numbers of CD4(+) and CD8(+) T-cells and NK cells in gallbladder cancer tissues were significantly higher than those in the surrounding tissue and gallbladder with gallstone. However, the ratio of CD4(+)/CD8(+) was lower in the cancer tissue than that in the surrounding tissue and tissue from gallbladders with gallstones. The distribution of CD4(+) and CD8(+) T-cells and NK cells in mucous membrane of cholecystitis gallbladder and that in the tissue surrounding gallbladder cancer were significantly different. CONCLUSIONS: Disproportionate and imbalanced distribution of NK cells and subsets of T-lymphocytes occurs in the mucous membrane proper of gallbladder cancer and surrounding tissue. Although gallbladder cancer tissue has higher expressions of CD4(+), CD8(+) and NK cells, the immune function is low or in an inhibited state. In gallbladder cancer immunization therapy, local cellular immunological function should be enhanced and the protective barrier improved. 展开更多
关键词 gallbladder cancer T-lymphocyte subset natural killer cell
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OSG中三维场景构建的关键技术 被引量:13
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作者 项杰 靳媛媛 李爱光 《地理空间信息》 2012年第1期43-45,2,共3页
随着基于OpenGL的各种三维渲染引擎的日趋成熟,如何更好地利用这些引擎已成为人们首先要解决的问题,而OpenSceneGraph作为一款高性能的、开源的渲染引擎也越来越受到人们的关注。系统地对OSG的结构和特性进行了分析,并对OSG中三维场景... 随着基于OpenGL的各种三维渲染引擎的日趋成熟,如何更好地利用这些引擎已成为人们首先要解决的问题,而OpenSceneGraph作为一款高性能的、开源的渲染引擎也越来越受到人们的关注。系统地对OSG的结构和特性进行了分析,并对OSG中三维场景的构建过程以及其中的一些关键技术如三维场景的数据组织、场景的裁剪技术、渲染的流程等进行了研究。 展开更多
关键词 OSG 三维场景 渲染引擎 数据组织 裁剪 构建技术 地形生成
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基于分组的分布式节点调度覆盖算法 被引量:11
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作者 李小龙 林亚平 +1 位作者 胡玉鹏 刘永和 《计算机研究与发展》 EI CSCD 北大核心 2008年第1期180-187,共8页
当部署的传感器节点服从随机分布时,现有的基于分组的节点调度算法不能保证各个组内的节点均匀分布在目标区域.基于以上原因,建立了极大相似分布模型,并提出了极大相似分布的一种近似求解算法:基于分组的分布式节点调度覆盖算法.算法仅... 当部署的传感器节点服从随机分布时,现有的基于分组的节点调度算法不能保证各个组内的节点均匀分布在目标区域.基于以上原因,建立了极大相似分布模型,并提出了极大相似分布的一种近似求解算法:基于分组的分布式节点调度覆盖算法.算法仅需要簇内的节点维持时钟同步,簇之间节点的时钟异步对于覆盖效果的影响可以忽略,因此适用于难以维持整个网络保持时间同步的大型传感器网络.此外,给出了在节点随机分布的条件下,采用分组调度时平均覆盖率的理论上界值.仿真实验表明,提出的这种算法能使各个组内的传感器节点较为均匀地分布在目标区域,获得的平均覆盖率接近于上界值. 展开更多
关键词 传感器网络 覆盖 节点调度 分组 极大相似分布
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慢性支气管炎急性发作期患者T淋巴细胞亚群的研究 被引量:10
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作者 高越 何建如 +2 位作者 陈小青 缪群 许国根 《科技通报》 北大核心 2001年第2期67-69,共3页
对慢性支气管炎急性发作期和缓解期患者体内 T淋巴细胞亚群进行研究 .用荧光单抗CD4 +、CD8+/CD2 8-,CD8+/CD2 8+对 T淋巴细胞亚群进行标记和计数 .检测结果显示慢性支气管炎急性发作期患者体内 CD4 +无明显变化 ;CD8+/CD2 8-增加 ;CD8+... 对慢性支气管炎急性发作期和缓解期患者体内 T淋巴细胞亚群进行研究 .用荧光单抗CD4 +、CD8+/CD2 8-,CD8+/CD2 8+对 T淋巴细胞亚群进行标记和计数 .检测结果显示慢性支气管炎急性发作期患者体内 CD4 +无明显变化 ;CD8+/CD2 8-增加 ;CD8+/CD2 8+减少 .我们认为慢性支气管炎急性期患者 T淋巴细胞亚群变化造成免疫功能紊乱 .因此在治疗疾病过程中 ,除对症处理外 ,另须配合使用提高免疫功能药物 。 展开更多
关键词 亚群 T淋巴细胞 支气管炎 患者 慢性支气管炎 急性发作期 外周血淋巴细胞 免疫系统
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Random dynamic analysis of vertical train–bridge systems under small probability by surrogate model and subset simulation with splitting 被引量:10
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作者 Huoyue Xiang Ping Tang +1 位作者 Yuan Zhang Yongle Li 《Railway Engineering Science》 2020年第3期305-315,共11页
The response of the train–bridge system has an obvious random behavior.A high traffic density and a long maintenance period of a track will result in a substantial increase in the number of trains running on a bridge... The response of the train–bridge system has an obvious random behavior.A high traffic density and a long maintenance period of a track will result in a substantial increase in the number of trains running on a bridge,and there is small likelihood that the maximum responses of the train and bridge happen in the total maintenance period of the track.Firstly,the coupling model of train–bridge systems is reviewed.Then,an ensemble method is presented,which can estimate the small probabilities of a dynamic system with stochastic excitations.The main idea of the ensemble method is to use the NARX(nonlinear autoregressive with exogenous input)model to replace the physical model and apply subset simulation with splitting to obtain the extreme distribution.Finally,the efficiency of the suggested method is compared with the direct Monte Carlo simulation method,and the probability exceedance of train responses under the vertical track irregularity is discussed.The results show that when the small probability of train responses under vertical track irregularity is estimated,the ensemble method can reduce both the calculation time of a single sample and the required number of samples. 展开更多
关键词 Train–bridge system Ensemble method Surrogate model Nonlinear autoregressive with exogenous input subset simulation with splitting Small probability
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Review of the SBAS InSAR Time-series algorithms, applications, and challenges 被引量:9
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作者 Shaowei Li Wenbin Xu Zhiwei Li 《Geodesy and Geodynamics》 CSCD 2022年第2期114-126,共13页
In the past 30 years,the small baseline subset(SBAS)InSAR time-series technique has emerged as an essential tool for measuring slow surface displacement and estimating geophysical parameters.Because of its ability to ... In the past 30 years,the small baseline subset(SBAS)InSAR time-series technique has emerged as an essential tool for measuring slow surface displacement and estimating geophysical parameters.Because of its ability to monitor large-scale deformation with millimeter accuracy,the SBAS method has been widely used in various geodetic fields,such as ground subsidence,landslides,and seismic activity.The obtained long-term time-series cumulative deformation is vital for studying the deformation mecha-nism.This article reviews the algorithms,applications,and challenges of the SBAS method.First,we recall the fundamental principle and analyze the shortcomings of the traditional SBAS algorithm,which provides a basic framework for the following improved time series methods.Second,we classify the current improved SBAS techniques from different perspectives:solving the ill-posed equation,increasing the density of high-coherence points,improving the accuracy of monitoring deformation and measuring the multi-dimensional deformation.Third,we summarize the application of the SBAS method in monitoring ground subsidence,permafrost degradation,glacier movement,volcanic activity,landslides,and seismic activity.Finally,we discuss the difficulties faced by the SBAS method and explore its future development direction. 展开更多
关键词 INSAR Small baseline subset Time-series InSAR DEFORMATION
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扇束图像重建中OSEM算法及子集划分的研究 被引量:10
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作者 印胤 刘力 《CT理论与应用研究(中英文)》 2003年第3期1-8,共8页
将一种快速迭代图像重建方法OSEM用于仿真Phantom模型的扇束投影数据的重建中,验证其重建参数的有效取值范围,分析比较不同子集选取对扇束OSEM重建的图像质量以及收敛速度的影响。方法: 本研究采用事先计算特定几何扇束扫描的概率矩阵... 将一种快速迭代图像重建方法OSEM用于仿真Phantom模型的扇束投影数据的重建中,验证其重建参数的有效取值范围,分析比较不同子集选取对扇束OSEM重建的图像质量以及收敛速度的影响。方法: 本研究采用事先计算特定几何扇束扫描的概率矩阵和最大间距划分投影子集的方法,选取图像大小为128*128。通过对模拟的Phantom扇束投影数据的重建,结果: OSEM重建效果好于传统滤波反投影(FBP)重建的结果,尤其是在有噪声情况下,在一定范围内重建质量与迭代次数和子集划分个数成正比,而计算时间仅仅与迭代次数正比。结论: 恰当地选取子集个数,扇束OSEM重建可用较少迭代次数和较短的计算时间获取好的重建图像。 展开更多
关键词 有序子集最大期望值方法 子集 扇束重建 图像
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Investigation of Combining Plant Genotypic Values and Molecular Marker Information for Constructing Core Subsets 被引量:7
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作者 Jian-Cheng Wang Jin Hu Ning-Ning Liu Hai-Ming Xu Sheng Zhang 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第11期1371-1378,共8页
In the present study, a strategy was proposed for constructing plant core subsets by clusters based on the combination of continuous data for genotypic values and discrete data for molecular marker InformaUon. A mixed... In the present study, a strategy was proposed for constructing plant core subsets by clusters based on the combination of continuous data for genotypic values and discrete data for molecular marker InformaUon. A mixed linear model approach was used to predict genotyplc values for eliminating the environment effect. The "mixed genetic distance" was designed to solve the difficult problem of combining continuous and discrete data to construct a core subset by cluster. Four commonly used genetic distances for continuous data (Euclidean distance, standardized Euclidean distance, city block distance, and Mahalanobls distance) were used to assess the validity of the conUnuous data part of the mixed genetic distance; three commonly used genetic distances for discrete data (cosine distance, correlaUon distance, and Jaccard distance) were used to assess the validity of the discrete data part of the mixed genetic distance, A rice germplasm group with eight quantitative traits and information for 60 molecular markers was used to evaluate the validity of the new strategy. The results suggest that the validity of both parts of the mixed geneUc distance are equal to or higher than the common geneUc distance. The core subset constructed on the basis of a combination of data for genotyplc values and molecular marker information was more representative than that constructed on the basis of data from genotypic values or molecular marker informaUon alone. Moreover, the strategy of using combined data was able to treat dominant marker informaUon and could combine any other continuous data and discrete data together to perform cluster to construct a plant core subset. 展开更多
关键词 cluster core subset genotypic value mixed linear model molecular marker information
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Unitariness in Ordered Semigroups
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作者 Michael Tsingelis 《Applied Mathematics》 2023年第8期531-543,共13页
We introduce the concepts of unitary, almost unitary and strongly almost unitary subset of an ordered semigroup. For the notions of almost unitary and strongly almost unitary subset of an ordered semigroup, we use the... We introduce the concepts of unitary, almost unitary and strongly almost unitary subset of an ordered semigroup. For the notions of almost unitary and strongly almost unitary subset of an ordered semigroup, we use the notion of translational hull of an ordered semigroup. If (S,⋅,≤) is an ordered semigroup having an element e such that e ≤ e<sup>2</sup> and U is a nonempty subset of S such that u ≤ eu, u ≤ ue for all u ∈ U, we show that U is almost unitary in S if and only if U is unitary in . Also if (S,⋅,≤) is an ordered semigroup, e ∉ S, U is a nonempty subset of S, S<sup>e</sup>:= S ∪ {e} and U<sup>e</sup>:= U ∪ {e}, we give conditions that an (“extension” of S) ordered semigroup and the subset U<sup>e</sup> of S<sup>e</sup> must satisfy in order for U to be almost unitary or strongly almost unitary in S (in case U is strongly almost unitary in S, then the given conditions are equivalent). 展开更多
关键词 Left (Right) Translation of an Ordered Semigroup Bitranslation of an Ordered Semigroup Translational Hull of an Ordered Semigroup Unitary subset of an Ordered Semigroup Almost Unitary subset of an Ordered Semigroup Strongly almost Unitary subset of an Ordered Semigroup
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慢性病毒性肝炎患者血清IL-12水平、T细胞亚群变化及相互关系的研究 被引量:6
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作者 闫峻 申吉子 李东复 《吉林医学》 CAS 2002年第6期346-347,共2页
目的 :研究慢性病毒性肝炎患者血清IL 12水平、T细胞亚群变化及相互关系。方法 :分别采用双抗体夹心ELISA法与抗体致敏的红细胞花环试验法 ,对 6 8例慢性病毒性肝炎患者血清IL 12水平及T细胞亚群进行了测定。结果 :慢性病毒性肝炎患者IL... 目的 :研究慢性病毒性肝炎患者血清IL 12水平、T细胞亚群变化及相互关系。方法 :分别采用双抗体夹心ELISA法与抗体致敏的红细胞花环试验法 ,对 6 8例慢性病毒性肝炎患者血清IL 12水平及T细胞亚群进行了测定。结果 :慢性病毒性肝炎患者IL 12水平明显低于正常对照组 ,以慢性重型肝炎为最低 ;CD4+ 细胞、CD4+ /CD8+ 比值明显降低 ,与血清IL 12水平呈正相关 ;而CD8+ 细胞则明显增高 ,与血清IL 12水平呈负相关。结论 :慢性病毒性肝炎患者存在细胞免疫功能低下 ,免疫调节功能紊乱 ,IL 12及T细胞亚群共同参与慢性病毒性肝炎的发病过程 ,也为临床上应用IL 展开更多
关键词 慢性病毒性肝炎 T细胞亚群 IL-12
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乙肝疫苗免疫前后淋巴细胞表型研究 被引量:7
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作者 李菁华 李长城 +1 位作者 关显智 王长宏 《中国实验诊断学》 2001年第6期314-315,共2页
目的 了解乙肝疫苗(HBsAg)免疫后健康成人外周血T淋巴细胞的表型变化,分析表型变化和是否产生抗体应答或弱应答的关系。方法 应用间接免疫荧光法原理和FACScan流式细胞仪分析了免疫后健康成人外周血T淋巴细胞的表型变... 目的 了解乙肝疫苗(HBsAg)免疫后健康成人外周血T淋巴细胞的表型变化,分析表型变化和是否产生抗体应答或弱应答的关系。方法 应用间接免疫荧光法原理和FACScan流式细胞仪分析了免疫后健康成人外周血T淋巴细胞的表型变化;同时应用ELISA原理,检测了免疫后HBV相关抗体。结果和结论 免疫后CD3+细胞和CD4+细胞活化增生,提高了机体的免疫调节能力;同时测定了HBsAb的阳性率。 展开更多
关键词 T淋巴细胞 表型 HBSAG 乙型肝炎 HBSAG
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