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Marginal Selenium Deficiency Alternates Inflammatory Response through NF-κB Pathway in LPS-induced Mouse Mastitis Model
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作者 Zhang Yixin Sun Qiaochu +3 位作者 Luo Tianning Zhang Huayu Wang Fucheng Zhang Wen 《Journal of Northeast Agricultural University(English Edition)》 2025年第2期37-46,共10页
The trace element selenium(Se)occurs naturally throughout the earth.Se deficiency has been linked to impaired breast health and other diseases in human and animals.Compared to severe Se deficiency,marginal dietary Se ... The trace element selenium(Se)occurs naturally throughout the earth.Se deficiency has been linked to impaired breast health and other diseases in human and animals.Compared to severe Se deficiency,marginal dietary Se deficiency accusers more frequently in low-Se regions.Therefore,to investigate the Se status and inflammatory response of the mammary gland under marginal dietary Se levels,an lipopolysaccharide(LPS)induced mouse mastitis model was established.Mice were fed with moderate Se diet(0.087 mg•kg^(-1) Se),adequate Se diet(0.15 mg•kg^(-1) Se)or excessive Se diet(1.5 mg•kg^(-1) Se)for 60 days.Se status and inflammatory factors were investigated.Results showed that the Se status of mammary gland correlated with dietary Se levels.Marginal Se deficiency exacerbated mammary tissue histopathology;increased the mRNA level of inflammatory genes tumor necrosis factor alpha(TNF-α),interleukin-1β(IL-1β)and cyclooxygenase-2(COX-2);and enhanced the phosphorylation of NF-κB p65 in mammary gland tissues.Supplementation of Se in diet higher than recommended levels reduced the inflammatory reaction of mammary glands in LPS-induced mastitis model and provided a protective effect. 展开更多
关键词 marginAL selenium deficiency MASTITIS INFLAMMATION NF-κB signal pathway
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基于不同Margin的人脸特征选择及识别方法 被引量:2
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作者 李伟红 陈伟民 +1 位作者 杨利平 龚卫国 《电子与信息学报》 EI CSCD 北大核心 2007年第7期1744-1748,共5页
Margin在机器学习中具有很重要的意义,基于margin的特征选择方法就是从分类的角度对特征集各特征的权重进行分析。该文对不同的margin进行了分析,提出将sample-margin和hypothesis-margin分别作为特征选择标准对SBS特征选择方法进行改进... Margin在机器学习中具有很重要的意义,基于margin的特征选择方法就是从分类的角度对特征集各特征的权重进行分析。该文对不同的margin进行了分析,提出将sample-margin和hypothesis-margin分别作为特征选择标准对SBS特征选择方法进行改进,然后设计具有最佳超参数的SVM多项式分类器进行人脸识别。实验在FRERT人脸图像库上进行并与Relief特征选择方法进行了比较,对SVM和NN分类器的实验结果也进行了分析。实验结果显示:该文提出的人脸识别特征选择及识别方法是有效、适用的。 展开更多
关键词 人脸识别 margin 特征选择 支持向量机(SVM) 顺序后退法(SBS)
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基于权重一致性优化的实时Marginalized粒子滤波算法 被引量:2
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作者 胡振涛 刘先省 +1 位作者 金勇 侯彦东 《电子学报》 EI CAS CSCD 北大核心 2014年第10期1970-1976,共7页
针对Marginalized粒子滤波中随机量测噪声对于非线性状态估计精度的不利影响以及线性状态估计中计算量较大问题,提出了一种基于权重一致性优化的实时Marginalized粒子滤波算法.首先,结合量测系统建模中先验信息的提取和利用,通过粒子权... 针对Marginalized粒子滤波中随机量测噪声对于非线性状态估计精度的不利影响以及线性状态估计中计算量较大问题,提出了一种基于权重一致性优化的实时Marginalized粒子滤波算法.首先,结合量测系统建模中先验信息的提取和利用,通过粒子权重间一致性距离和一致性矩阵的构建,提出了量测提升策略下权重的一致性优化方法,以改善粒子滤波在非线性状态估计中的滤波精度.其次,通过对Marginalized粒子滤波实现中时间更新和量测更新环节的结构优化,给出了实时Marginalized粒子滤波,以降低蒙特卡罗仿真实现下卡尔曼滤波在状态线性估计中的计算复杂度.最后,在两者的动态结合基础上给出了新算法具体实现步骤.利用基于单站雷达目标跟踪仿真场景,分析了算法性能.理论分析和仿真实验结果验证了算法的可行性和有效性. 展开更多
关键词 非线性估计 marginalized粒子滤波 量测提升 权重优化
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快速Marginalized粒子滤波器在纯方位跟踪中的应用 被引量:1
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作者 薛锋 刘忠 石章松 《火力与指挥控制》 CSCD 北大核心 2008年第11期66-68,72,共4页
为提高纯方位跟踪性能,降低粒子滤波方法的运算量,在原有Marginalized粒子滤波器(MPF)的基础上,对线性部分处理方法进行简化,提出了快速Marginalized粒子滤波器(FMPF),并结合纯方位跟踪模型,推导了FMPF应用的具体算法步骤,使用机动目标... 为提高纯方位跟踪性能,降低粒子滤波方法的运算量,在原有Marginalized粒子滤波器(MPF)的基础上,对线性部分处理方法进行简化,提出了快速Marginalized粒子滤波器(FMPF),并结合纯方位跟踪模型,推导了FMPF应用的具体算法步骤,使用机动目标纯方位跟踪仿真实例,与其他滤波器进行了仿真对比,分析了跟踪性能和计算量。仿真结果表明,与标准粒子滤波器相比,FMPF可以提高线性部分的计算精度,同时减少MPF所需的计算量。 展开更多
关键词 纯方位跟踪 粒子滤波 marginalized粒子滤波器 运算时间
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Analyzing our educational resource deployment of compulsory education by marginal utility
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作者 高丽 程宝良 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2006年第S1期353-356,共4页
In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment ... In the base of utility and marginal utility,the article put forwardthe concept of utility and marginal utilityof educational outlay and the theory of them,and analyzed the actuality of educational resource deployment in ourcountry,gave some advice about howtoi mprove our educational resource deployment of compulsory education. 展开更多
关键词 marginal utility educational resource compulsory education
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最大化最小margin的抽样多样性集成学习方法研究 被引量:2
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作者 周钢 郭福亮 《计算机应用与软件》 北大核心 2020年第8期300-306,共7页
从偏差-方差分解和误差-分歧分解角度,发现集成学习中的基分类器多样性是提升集成学习泛化能力和分类精度的重要途径,在数据样本中通过最大化最小margin的方法能够有效提升集成学习多样性。针对Bagging算法,提出一种基于最大化最小margi... 从偏差-方差分解和误差-分歧分解角度,发现集成学习中的基分类器多样性是提升集成学习泛化能力和分类精度的重要途径,在数据样本中通过最大化最小margin的方法能够有效提升集成学习多样性。针对Bagging算法,提出一种基于最大化最小margin的优化集成学习算法。通过优化抽样方法实现最大化最小margin,将该问题简化为基分类器权重调整问题;通过给正确分类易错数据样本的基分类器赋予更高权重来实现在集成学习抽样中该类数据样本的margin值最大化。实验结果表明,该算法对比常用集成学习方法在大部分数据集上具有更高的执行效率和泛化精度。 展开更多
关键词 集成学习 多样性 margin BAGGING 动态权重
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STRUCTURAL AND THERMAL EVOLUTION OF THE SOUTH ASIAN CONTINENTAL MARGIN ALONG THE KARAKORAM AND HINDU KUSH RANGES,NORTH PAKISTAN 被引量:7
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作者 M.P.Searle\+1, J.E.Fraser\+1, P.R.Hildebrand\+1, R.R. Parrish\+2, S.R.Noble\+2(1.Dept. Earth Sciences, Oxford University, Park Rd., Oxford, UK 2.NERC Isotope Geosciences Laboratory, Keyworth, Nottingham, UK) 《地学前缘》 EI CAS CSCD 2000年第S1期82-83,共2页
Prior to the collision and accretion of the Kohistan arc terrane during the late Cretaceous and the Indian plate after the early Eocene, the southern margin of Asia along the Hindu Kush, Karakoram and Lhasa block terr... Prior to the collision and accretion of the Kohistan arc terrane during the late Cretaceous and the Indian plate after the early Eocene, the southern margin of Asia along the Hindu Kush, Karakoram and Lhasa block terranes was an active Andean\|type continental margin. In south Tibet this margin was dominated by the calc\|alkaline Ladakh—Gangdese granite batholith, associated andesitic volcanic rocks and continental red\|beds. In contrast, the southern Karakoram exposes deep crustal metamorphic rocks and crustal melt leucogranites. New U\|Pb age dating from the Hunza valley and Baltoro glacier region has revealed four spatially and temporally distinct metamorphic episodes. M1 sillimanite grade metamorphism in Hunza was a late Cretaceous event, probably caused by the accretion of the Kohistan arc to Asia. M2 was the major kyanite and sillimanite grade event during late Eocene—Oligocene crustal thickening and shortening, following India\|Asia collision. Numerous melting events resulted in the formation of crustal melt granites throughout the last 50Ma with multiple generations of dykes and very large scale crustal melting along the Baltoro monzogranite\|leucogranite ba tholith during the late Oligocene—early Miocene. M3 metamorphism was a high\| T , low\| p contact thermal metamorphism around the Baltoro granite. In Hunza, younger staurolite grade metamorphism has been dated by U\|Pb monazites at 16Ma, with the Sumayar leucogranite intruded at 9 5Ma cross\|cutting the metamorphic isograds. In the Baltoro region the youngest metamorphism, M4, is the sillimanite grade Dassu gneiss core complex dated by U\|Pb on monazites as late Miocene—Pliocene (5 4±0 25)Ma with Precambrian protolith zircon cores (1855±11)Ma. Numerous gem\|bearing pegmatite dykes cross\|cut these rocks and are thought to have been intruded within the last 2~3Ma. Structural mapping, combined with U\|Pb geochronology shows that major metamorphic events can be both long\|lasting (up to 20Ma) and very restrictive, both in time and space. 展开更多
关键词 STRUCTURAL and thermal evolution CONTINENTAL margin KARAKORAM HINDU Kush RANGES NORTH Pakistan Asian plate
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Marginal optimization method to improve the inconsistent comparison matrix in the analytic hierarchy process 被引量:11
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作者 Shihui Wu Jiang Xie +3 位作者 Xiaodong Liu Bo He Minxiang Yang Zhengxin Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第6期1141-1151,共11页
To improve the inconsistency in the analytic hierarchy process(AHP), a new method based on marginal optimization theory is proposed. During the improving process, this paper regards the reduction of consistency ratio(... To improve the inconsistency in the analytic hierarchy process(AHP), a new method based on marginal optimization theory is proposed. During the improving process, this paper regards the reduction of consistency ratio(CR) as benefit, and the maximum modification compared to the original pairwise comparison matrix(PCM) as cost, then the improvement of consistency is transformed to a benefit/cost analysis problem. According to the maximal marginal effect principle, the elements of PCM are modified by a fixed increment(or decrement) step by step till the consistency ratio becomes acceptable, which can ensure minimum adjustment to the original PCM so that the decision makers’ judgment is preserved as much as possible. The correctness of the proposed method is proved mathematically by theorem. Firstly, the marginal benefit/cost ratio is calculated for each single element of the PCM when it has been modified by a fixed increment(or decrement).Then, modification to the element with the maximum marginal benefit/cost ratio is accepted. Next, the marginal benefit/cost ratio is calculated again upon the revised matrix, and followed by choosing the modification to the element with the maximum marginal benefit/cost ratio. The process of calculating marginal effect and choosing the best modified element is repeated for each revised matrix till acceptable consistency is reached, i.e., CR<0.1. Finally,illustrative examples show the proposed method is more effective and better in preserving the original comparison information than existing methods. 展开更多
关键词 analytic hierarchy process(AHP) comparison matrix CONSISTENCY marginal optimization
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Mineralogy and fracture development characteristics of marine shale-gas reservoirs: A case study of Lower Silurian strata in southeastern margin of Sichuan Basin, China 被引量:3
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作者 郭岭 姜在兴 郭峰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1847-1858,共12页
Mineral contents and fractures of shale from well Yuye-1 and outcrops were examined mainly based on systematic description of the cores and outcrops, and data from experimental analyses. The data enabled us to thoroug... Mineral contents and fractures of shale from well Yuye-1 and outcrops were examined mainly based on systematic description of the cores and outcrops, and data from experimental analyses. The data enabled us to thoroughly explore the mineralogy and developmental features of shale of the Lower Silurian Longmaxi Formation in the study area. The results show that,the Lower Silurian Longmaxi Shale(SLS) in the southeastern margin of Sichuan Basin, China, is primarily characterized by a high content of brittle minerals and a relatively low content of clay minerals. The total content of brittle minerals is approximately 57%,including 27% quartz, 12.2% feldspar, 11.2% carbonate and 2.4% pyrite. The total content of clay minerals reaches 41.6%,composed of illite(23.8%), mixed-layer of illite and smectite(I/S)(10.8%) and chlorite(7.0%). The SLS accommodates the widespread development of various types of fractures, including tectonic fractures, diagenetic fractures, inter-layer fractures and slip fractures. The developmental level of the fracture in the SLS is mainly influenced by faults, lithology, mineral contents and total organic carbon content(TOC) in study area. 展开更多
关键词 shale fracture MINERALOGY gas shale Lower Silurian margin of Sichuan Basin
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基于自适应粒子群优化的代价评估Marginalized粒子滤波 被引量:1
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作者 胡振涛 魏丹 +1 位作者 金勇 胡玉梅 《计算机科学》 CSCD 北大核心 2014年第6期199-203,共5页
针对量测受扰动情况下粒子重要性权重的精确度量和粒子的有效采样问题,提出了一种基于自适应粒子群优化的代价评估Marginalized粒子滤波。首先,在Marginalized粒子滤波框架下,通过引入代价函数和风险函数,实现了粒子重要性权重评价过程... 针对量测受扰动情况下粒子重要性权重的精确度量和粒子的有效采样问题,提出了一种基于自适应粒子群优化的代价评估Marginalized粒子滤波。首先,在Marginalized粒子滤波框架下,通过引入代价函数和风险函数,实现了粒子重要性权重评价过程中对最新量测信息的合理利用,以降低传统的依据重要性权重度量方式中对于噪声先验信息的依赖。其次,通过对粒子分布特征信息的提取和利用,构建了粒子极限速度设定的自适应选取策略,给出了一种自适应粒子群优化方法。在此基础上,结合粒子群优化中群体优化机理来提升采样粒子对被估计状态的逼近程度,进而改善重采样后粒子的多样性。理论分析和仿真实验验证了算法的有效性。 展开更多
关键词 非线性滤波 代价评估粒子滤波 粒子群优化 量测不确定
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DISCUSSION ON RELATIONSHIP BETWEEN WESTERN MARGIN OF YANGTZE BLOCK AND SOUTHWESTERN SANJIANG REGION IN PROTEROZOIC 被引量:1
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作者 Li Zhongxiong, Cheng Ming, Guan Shiping 《地学前缘》 EI CAS CSCD 2000年第S1期317-318,共2页
The western margin of Yangtze block and southwestern Sanjiang region absorbed much attention from geologists. It has been proved that there occurred a series of plate subduction, collision, assembly, rifting and break... The western margin of Yangtze block and southwestern Sanjiang region absorbed much attention from geologists. It has been proved that there occurred a series of plate subduction, collision, assembly, rifting and breakup processes between them since Palaeozoic and the tectonic evolutionary relationship between them is clear. But in Proterozoic this kind of links between them became unclear. Did they undergo the assembly and breakup processes of the Rodinia super continent? This paper will take a primary discussion on this question on the basis of basement component, structure characteristics and magmatic activities.1\ Basement features\;(1) In western margin of Yangtze block its basement is composed of crystalline basement and folded basement, a so\|called double\|layer structure. The crystalline basement is made up of Kangding group, Pudeng Formation and Dibadu Formation, among them Kangding group is a representative and composed mainly of migmatite, compositing gneiss, hornblende schist and granulitite. The isotopic age of crystalline basement is older than 1900Ma, so its geological time is late Archaean to early Proterozoic. The folded basement is composed of Dahongshan group, Hekou group, Kunyang group, Huili group and Yanbian group. Their rock associations are made up mainly of spilite\|keratophyre formation, carbonate formation, clastic rock and clastic rock formation with some basic volcanic rocks. The folded basement is assigned to be early and middle Proterozoic (1000~1700M a). 展开更多
关键词 PROTEROZOIC basement structure ophiolite suite GRENVILLE orogenic belt WESTERN margin of Yangtze block SOUTHWESTERN Sanjiang REGION
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Margin optimization algorithm for digital subscriber lines based on particle swarm optimization 被引量:1
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作者 Tang Meiqin Guan Xinping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1316-1323,共8页
The margin maximization problem in digital subscriber line(DSL) systems is investigated.The particle swarm optimization(PSO) theory is applied to the nonconvex margin optimization problem with the target power and... The margin maximization problem in digital subscriber line(DSL) systems is investigated.The particle swarm optimization(PSO) theory is applied to the nonconvex margin optimization problem with the target power and rate constraints.PSO is a new evolution algorithm based on the social behavior of swarms, which can solve discontinuous, nonconvex and nonlinear problems efficiently.The proposed algorithm can converge to the global optimal solution, and numerical example demonstrates that the proposed algorithm can guarantee the fast convergence within a few iterations. 展开更多
关键词 digital subscriber line margin NONCONVEX particle swarm optimization.
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Kernel density estimation and marginalized-particle based probability hypothesis density filter for multi-target tracking 被引量:3
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作者 张路平 王鲁平 +1 位作者 李飚 赵明 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期956-965,共10页
In order to improve the performance of the probability hypothesis density(PHD) algorithm based particle filter(PF) in terms of number estimation and states extraction of multiple targets, a new probability hypothesis ... In order to improve the performance of the probability hypothesis density(PHD) algorithm based particle filter(PF) in terms of number estimation and states extraction of multiple targets, a new probability hypothesis density filter algorithm based on marginalized particle and kernel density estimation is proposed, which utilizes the idea of marginalized particle filter to enhance the estimating performance of the PHD. The state variables are decomposed into linear and non-linear parts. The particle filter is adopted to predict and estimate the nonlinear states of multi-target after dimensionality reduction, while the Kalman filter is applied to estimate the linear parts under linear Gaussian condition. Embedding the information of the linear states into the estimated nonlinear states helps to reduce the estimating variance and improve the accuracy of target number estimation. The meanshift kernel density estimation, being of the inherent nature of searching peak value via an adaptive gradient ascent iteration, is introduced to cluster particles and extract target states, which is independent of the target number and can converge to the local peak position of the PHD distribution while avoiding the errors due to the inaccuracy in modeling and parameters estimation. Experiments show that the proposed algorithm can obtain higher tracking accuracy when using fewer sampling particles and is of lower computational complexity compared with the PF-PHD. 展开更多
关键词 particle filter with probability hypothesis density marginalized particle filter meanshift kernel density estimation multi-target tracking
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Formation and Evolution of the Late Mesozoic-Cenozoic Ruo'ergai Basin,Northeastern Margin of the Qinghai-Tibet Plateau
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作者 Yuxiu Zhang,Chengshan Wang,Meng He,Chao Ma,Xinsheng Niu 1.School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.Research Center for Tibetan Plateau Geology,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期275-275,共1页
The Middle Triassic Ladinian-Upper Triassic Norian series in the Mesozoic-Cenozoic Ruo’ergai basin of Songpan area is characterized of large thick shallow marine-deep marine fine grained clastic.The strata are region... The Middle Triassic Ladinian-Upper Triassic Norian series in the Mesozoic-Cenozoic Ruo’ergai basin of Songpan area is characterized of large thick shallow marine-deep marine fine grained clastic.The strata are regionally unconformable between each adjacent two of the Middle-Late Triassic fine grained clastic,the Jurassic coal-containing clastic,the Cretaceous-Paleogene variegated coarse clastic。 展开更多
关键词 FORMATION and EVOLUTION NORTHEASTERN margin Qinghai-Tibet PLATEAU
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STYLE AND CONSEQUENCE OF STRAIN PARTITION IN THE NORTHEAST MARGIN OF QINGHAI—TIBET PLATEAU
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作者 Shen Xuhui, Ding Guoyu, Tian Qinjian, Wei Kaibo, Chen Zhengwei 《地学前缘》 EI CAS CSCD 2000年第S1期248-248,共1页
The Northeastern margin of Qinghai—Tibet plateau,here refers to the region bounded by Western Qinling fault zone and Longshoushan—Liupanshan tectonic zone, where obliquely compression deformation occurred with the N... The Northeastern margin of Qinghai—Tibet plateau,here refers to the region bounded by Western Qinling fault zone and Longshoushan—Liupanshan tectonic zone, where obliquely compression deformation occurred with the NE\|trending maximum principle axis of stress, with Ordos Massif to the east, Alaxa Block to the north, and Qinghai—Tibet plateau to the southwest. The main structure in this region is Haiyuan—Gulang transpression zone. It consists of a series of active faults: the Haiyuan fault zone, the Tianjingshan fault zone, the Yantongshan fault zone and the Niushoushan—Luoshan fault zone. 展开更多
关键词 strain PARTITION STYLE CONSEQUENCE the northeast margin of Qinghai—Tibet Plateau
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NEOTECTONICS ALONG THE EASTERN MARGIN OF THE TIBETAN PLATEAU: INFERENCES FROM BEDROCK RIVER INCISION PATTERNS
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作者 Eric Kirby 1, Kelin X.Whipple 1, Tang W. 2, B.C.Burchfiel 1,Chen Z. 2 2 Chengdu Institute of Geology and Mineral Resources, Chengdu 610082,China) 《地学前缘》 EI CAS CSCD 2000年第S1期281-282,共2页
The topographic margin of the Tibetan Plateau adjacent to the Sichuan Basin is one of the World’s most impressive continental escarpments, rising from ~600 meters in the basin to peak elevations exceeding 6km across... The topographic margin of the Tibetan Plateau adjacent to the Sichuan Basin is one of the World’s most impressive continental escarpments, rising from ~600 meters in the basin to peak elevations exceeding 6km across a horizontal distance of only 50~60km. Despite this relief, recent geodetic results (King et al., 1997; Chen et al., 1999) indicate that active shortening across this margin of the plateau is <3mm/a, and is within uncertainty of zero. Recent geodynamic models for active deformation in eastern Tibet (Royden et al., 1997) explain this discrepancy as a consequence of flow of lower crust from beneath the central plateau. These models predict relatively high rates of rock uplift in the near absence of horizontal shortening. Rivers along this margin of the plateau are actively incising into bedrock and afford the opportunity to better resolve the distribution of rock uplift along the margin. 展开更多
关键词 NEOTECTONICS the eastern margin the TIBETAN PLATEAU
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Cu-Ni-PGES MINERALIZATION OF MELANOCRATIC ROCKS IN SOUTHEAST MARGIN OF THE QINGHAI-XIZANG(TIBET) PLATEAU, HKT
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作者 Cao Zhimin 1, Luo Yaonan 2, Li Youguo 1, Song Xieyan 1, Chen Cuihua 1, Yang Zhusheng 2, He Hong 2 2 Sichuan Bureau of geology and Mineral Resources, Chengdu 610081,China) 《地学前缘》 EI CAS CSCD 2000年第S1期415-415,共1页
The Panxi Rift Zone is a famous metallogenic province in Southwest China. Continental rifting developed in Hercynian period (P 2, 260~250Ma) accompany with a series of basic\|ultrabasic rocks. Various in lithologies,... The Panxi Rift Zone is a famous metallogenic province in Southwest China. Continental rifting developed in Hercynian period (P 2, 260~250Ma) accompany with a series of basic\|ultrabasic rocks. Various in lithologies, such as layered intrusions (V\|Ti\|Fe formation), small\|sized mafic\|ultramafic bodies (stocks) and large\|scale basalt (Emeishan Basalt) are constituted of a complete melanocratic rock system.Most of Cu\|Ni\|PGE sulfide deposits are related to small\|sized ultramafic rock bodies. It is a perfect possibility for them to be an affinity of basic eruptive lava and for the neck facies. But in ① Panzhihua\|Center Yunnan Province, the Gaojiacun, also Jinbaoshan, as large stratiform basic\|ultrabasic complex used to be thought that is older one intruded to basement rocks in Precambrian. However, new evidences suggest it is similar with the small\|sized ultramafic rock bodies containing Cu\|Ni\|PGE, and also the both are affinity of the Emeishan Basalt; ② Miyi district, Cu\|Pt mineralization was discovered in the Xinjie bedded basic complex, and in where ophitic olivine\|pyroxenite\|peridotite facies are exactly Pt\|bearing layers; ③ Longzhoushan district, we have recently researched basic\|ultrabasic clusters which intruded into fracture zones, and Cu\|Ni\|Pt, Pd mineralization developed at the salbands.Generally, the basalt is poor in PGE and rich in Cu. It is suggested as the result of PGE dispersion\|concentration processing in the melanocratic rock system when rifting happened. 展开更多
关键词 Cu\|Ni\|PGEs MINERALIZATION Province melanocratic ROCKS em eishan basalt basic\|ultrabasic complex SOUTHEAST margin the Qinghai —Xizang(Tibet) PLATEAU HKT
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Passive target tracking using marginalized particle filter
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作者 Zhan Ronghui Wang Ling Wan Jianwei Sun Zhongkang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期503-508,共6页
A marginalized particle filtering (MPF) approach is proposed for target tracking under the background of passive measurement. Essentially, the MPF is a combination of particle filtering technique and Kalman filter. ... A marginalized particle filtering (MPF) approach is proposed for target tracking under the background of passive measurement. Essentially, the MPF is a combination of particle filtering technique and Kalman filter. By making full use of marginalization, the distributions of the tractable linear part of the total state variables are updated analytically using Kalman filter, and only the lower-dimensional nonlinear state variable needs to be dealt with using particle filter. Simulation studies are performed on an illustrative example, and the results show that the MPF method leads to a significant reduction of the tracking errors when compared with the direct particle implementation. Real data test results also validate the effectiveness of the presented method. 展开更多
关键词 nonlinear filtering passive target tracking particle filter marginalized particle filter state estimation.
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Parametric study on collapse margin ratio of structure
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作者 欧晓英 何政 欧进萍 《Journal of Central South University》 SCIE EI CAS 2014年第6期2477-2486,共10页
The determination of collapse margin ratio(CMR)of structure is influenced by many uncertain factors.Some factors that can affect the calculation of CMR,e.g.,the elongation of the structural fundamental period prior to... The determination of collapse margin ratio(CMR)of structure is influenced by many uncertain factors.Some factors that can affect the calculation of CMR,e.g.,the elongation of the structural fundamental period prior to collapse,the determination of earthquake intensity measure,the seismic hazard probability,and the difference of the spectral shapes between the median spectrum of the ground motions and the design spectrum,were discussed.Considering the elongation of the structural fundamental period,the intensity measure Sa(T1)should be replaced with *aS in the calculation of CMR for short-period and medium-period structures.The reasonable intensity measure should be determined by the correlation analysis between the earthquake intensity measure and the damage index of the structure.Otherwise,CMR should be adjusted according to the seismic hazard probability and the difference in the spectral shapes.For important long-period structures,CMR should be determined by the special site spectrum.The results indicate that both Sa(T1)and spectrum intensity(SI)could be used as intensity measures in the calculation of CMR for medium-period structures,but SI would be a better choice for long-period structures.Moreover,an adjusted CMR that reflects the actual seismic collapse safety of structures is provided. 展开更多
关键词 collapse margin ratio strong ground motion intensity measurement probability of exceedance Housner's spectrum intensity spectrum acceleration
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Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District,Southern Margin of the North China Craton
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作者 BI Shi-jian1,2,LI Jian-wei1,2,LI Zhan-ke1,2,ZHANG Su-xin1,ZHENG Shu1(1. State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,430074 Wuhan,China 2. Faculty of Earth Resources,China University of Geosciences,430074 Wuhan,China) 《矿物学报》 CAS CSCD 北大核心 2009年第S1期113-114,共2页
Gold is commonly associated with arsenic in As-rich pyrite or arsenopyrite in a variety types of gold deposit,such as sediment-hosted gold deposits,epithermal Au-Ag deposits,Au-rich VMS deposits,and mesothermal lode g... Gold is commonly associated with arsenic in As-rich pyrite or arsenopyrite in a variety types of gold deposit,such as sediment-hosted gold deposits,epithermal Au-Ag deposits,Au-rich VMS deposits,and mesothermal lode gold deposits(Ciobanu and Cook,2002;Pals et al. 展开更多
关键词 Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District Southern margin of the North China
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