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Comparison of LR,5-CV SVM,GA SVM,and PSO SVM for landslide susceptibility assessment in Tibetan Plateau area,China

Journal of Mountain science 2023年第4期20卷 979-995页

作者： zhang Ying-bin Xu Pei-yi LIu Jing HE jian-xian YANG Hao-tian ZENG Ying HE Yun-yong YANG Chang-feng Department of Geotechnical Engineering School of Civil EngineeringSouthwest Jiaotong UniversityChengdu610031China Sichuan Highway Planning SurveyDesign and Research Institute Ltd.Chengdu610041China

The applicability of statistics-based landslide susceptibility assessment methods is affected by the number of historical *** studies have proposed support vector machine(SVM)as a small-sample learning ***,those studies demonstrated that different parameters can affect model *** optimized the SVM and obtained models as 5-fold cross validation(5-CV)SVM,genetic algorithm(GA)SVM,and particle swarm optimization(PSO)*** study compared the prediction performances of logistic regression(LR),5-CV SVM,GA SVM,and PSO SVM on landslide susceptibility mapping,to explore the spatial distribution of landslide susceptibility in the study area in Tibetan Plateau,China.A geospatial database was established based on 392 historical landslides and 392 non-landslides in the study *** used 11 influencing factors of altitude,slope,aspect,curvature,lithology,normalized difference vegetation index(NDVI),distance to road,distance to river,distance to fault,peak ground acceleration(PGA),and rainfall to construct an influencing factor evaluation *** evaluate the models,four susceptibility maps were compared via receiver operating characteristics(ROC)curve and the results showed that prediction rates for the models are 84%(LR),87%(5-CV SVM),85%(GA SVM),and 90%(PSO SVM).We also used precision,recall,F1-score and accuracy to assess the quality performance of these *** results showed that the PSO SVM had greater potential for future implementation in the Tibetan Plateau area because of its superior performance in the landslide susceptibility assessment.

关键词： Tibetan Plateau area Logistic regression Support vector machine Landslide susceptibility assessment

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Nonlocal Denosing Method for Natural Image via 2DPCA and Direction Information 11th

Nonlocal Denosing Method for Natural Image via 2DPCA and Dir...

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2012 IEEE 11th International Conference on Signal Processing(ICSP 2012)

作者： Yu Hui Zheng Yao Wang jian Wei zhang Shun Feng Wang Xun Jie Chen College of Computer & Software Nanjing University of Information Science & Technology College of Math & statistics Nanjing University of Information Science & Technology

ISBN: (纸本)9781467321969

Recently, the Nonlocal means filter have has gained wide attention. unfortunately, the computational complexity of this methods is quite a burden. Several Speedup methods have been suggested. In our former work[17], we propose a scheme to more efficiently preselect similar patches, based on the two-dimensional principal component analysis（2DPCA）. Although the method can yield good results, the computational complexity remains high. Besides, both practice and theory proved that nonlocal mean filter is suitable for processing the texture image. For natural image, its performance still needs improvement. Hence we proposed improved Semi-nonlocal version of the 2DPCA NL-mean filter, which directly employs features extracted by the 2DPCA to compute the weights, meanwhile the direction information of image patch is also used to design the weights function. Experimental results show that our method can achieve better filtering results in a variety of images, such as weak gradient image, face image and texture image.

关键词： Nonlocal denosing 2DPCA Noise estimation Structure tensor

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DNA methylation markers in the diagnosis and prognosis of common leukemias

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Signal Transduction and Targeted Therapy 2020年第1期5卷 2468-2477页

作者： Hua jiang Zhiying Ou Yingyi He Meixing Yu Shaoqing Wu Gen Li Jie Zhu Ru zhang Jiayi Wang Lianghong Zheng Xiaohong zhang Wenge Hao Liya He Xiaoqiong Gu Qingli Quan Edward zhang Huiyan Luo Wei Wei Zhihuan Li Guangxi Zang Charlotte zhang Tina Poon Daniel zhang Ian Ziyar Run-ze zhang Oulan Li Linhai Cheng Taylor Shimizu Xinping Cui jian-kang Zhu Xin Sun kang zhang Guangzhou Women and Children’s Medical Center Guangzhou Medical UniversityGuangzhou 510623China Guangzhou Regenerative Medicine and Health Guangdong Laboratory Guangzhou 510005China State key Laboratory of Oncology Sun Yat-sen University Cancer CenterGuangzhou 510060China Department of statistics and institute for Integrative Genome Biology University of California RiversideRiversideCA 92521USA Shanghai Center for Plant Stress Biology Shanghai Institute for Biological SciencesChinese Academy of SciencesShanghai 210602China Faculty of Medicine Macao University of Science and TechnologyTaipaMacaoChina

The ability to identify a specific type of leukemia using minimally invasive biopsies holds great promise to improve the diagnosis,treatment selection,and prognosis prediction of *** genome-wide methylation profiling and machine learning methods,we investigated the utility of CpG methylation status to differentiate blood from patients with acute lymphocytic leukemia(ALL)or acute myelogenous leukemia(AML)from normal *** established a CpG methylation panel that can distinguish ALL and AML blood from normal blood as well as ALL blood from AML blood with high sensitivity and *** then developed a methylation-based survival classifier with 23 CpGs for ALL and 20 CpGs for AML that could successfully divide patients into high-risk and low-risk groups,with significant differences in clinical outcome in each leukemia ***,these findings demonstrate that methylation profiles can be highly sensitive and specific in the accurate diagnosis of ALL and AML,with implications for the prediction of prognosis and treatment selection.

关键词： diagnosis prognosis acute

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Radial velocity measurements from LAMOST medium-resolution spectroscopic observations: a pointing towards the kepler field

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Research in Astronomy and Astrophysics 2019年第5期19卷 133-140页

作者： Nian Liu jian-Ning Fu Weikai Zong jian-Rong Shi A-Li Luo Hao-Tong zhang Xiang-Qun Cui Yong-Hui Hou Yang Pan Xin-Rui Shan jian-Jun Chen Zhong-Rui Bai jian-Xing Chen Bing Du Wen Hou Yu-Chen Liu Hao Tian jiang-Tao Wang Jia-Xin Wang ke-Fei Wu Yu-Zhong Wu Hong-Liang Yan Fang Zuo Department of Astronomy Beijing Normal University key Lab for Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space science University of Chinese Academy of Sciences Nanjing institute of Astronomical Optics & Technology National Astronomical Observatories Chinese Academy of Sciences

Radial velocity is one of the key measurements in understanding the fundamental properties of stars, stellar clusters and the Galaxy. A plate of stars in the kepler field was observed in May of 2018 with the medium-resolution spectrographs of LAMOST, aiming to test the performance of this new system which is the upgraded equipment of LAMOST after the first five-year regular survey. We present our analysis on the radial velocity measurements(RVs) derived from these data. The results show that slight and significant systematic errors exist among the RVs obtained from the spectra collected by different spectrographs and exposures, respectively. After correcting the systematic errors with different techniques, the precision of RVs reaches ～1.3,～1.0,～0.5 and ～0.3 km s^(-1) at S/Nr = 10, 20, 50 and 100, respectively. Comparing with the RVs of standard stars from the APOGEE survey, our RVs are calibrated with a zero-point shift of～7 km s^(-1). The results indicate that the LAMOST medium-resolution spectroscopic system may provide RVs with a reasonable accuracy and precision for the selected targets.

关键词： technique:spectroscopy stars:radial velocity stars:statistics

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工程数字测井自动分层的人工智能技术

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天津大学学报（自然科学与工程技术版） 2001年第5期34卷 633-635页

作者：张献民王建华天津大学建筑工程学院岩土工程研究所天津300072

根据人工对测井资料分析的思维过程 ,应用模糊数学理论及统计学参数 ,建立了岩土性质识别及界面划分的人工智能数学模型 ,并研制了相应的软件 ,实现了工程数字测井的自动分层 .对离散的数字测井值 ,通过测井物理参数对地层性质的隶属函... 详细信息

根据人工对测井资料分析的思维过程 ,应用模糊数学理论及统计学参数 ,建立了岩土性质识别及界面划分的人工智能数学模型 ,并研制了相应的软件 ,实现了工程数字测井的自动分层 .对离散的数字测井值 ,通过测井物理参数对地层性质的隶属函数模型 ,逐一识别 ,然后进行聚类处理 ;对地层界面处由于邻层效应产生的模糊数据 ,分别计算其对上下层岩性的隶属度 ,采用主因素决定型算法实现界面划分 .应用结果表明 ,该方法简单。

关键词：工程数字测井自动分层人工智能岩石性质识别界面划分隶属函数

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The number of births in China in 2015： policy meets superstition

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science Bulletin 2018年第19期63卷 1235-1237页

作者： Hong-Tian Li Susan Hellerstein Chuyun kang Leonardo Trasande Yanqiu Gao Yali zhang Shusheng Luo Yu-Bo Zhou Jie Qiao Jan Blustein jian-Meng Liu institute of Reproductive and Child Health. National Health Commission key Laboratory of Reproductive Health Peking University Health Science Center Beijing 100191 China Office for National Maternal and Child Health statistics of China. School of Public Health Peking University Health Science Center Beijing 100191 China Department of Epidemiology and Biostatistics School of Public Health Peking University Health Science Center Beijing 100191 China Department of Obstetrics and Gynecology Brigham and Women's Hospital Harvard Medical School Boston MA 02115 USA Department of Child Adolescent and Women's Health School of Public Health Peking University Health Science Center Beijing 100191 China Departments of Pediatrics and Environmental Medicine NYU School of Medicine NY 100016 USA Department of Population Health NYU School of Medicine NY 100016 USA NYu Wagner School of Public Service NY 100012 USA Department of Obstetrics and Gynecology Center for Reproductive Medicine Peking University Third Hospital. Beijing 100191 China key Laboratory of Assisted Reproduction Ministry of Education Beijing 100191 China Reproductive Health Research Center of Peking university Health science Center Belting 100191 China

Fertility in China was long constrained by the One-Child policy enacted in 1978. Over time the policy was progressively relaxed,first in rural areas and then for couples who both had no siblings.A Selective Two-Child policy which started in January-June 2014allowed a second child for couples for whom one spouse was an only child. Now with the universal Two-Child policy, as of

关键词：中国迷信独生子女孩子

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基于固有光学量的高光谱数据反演城市河网水质

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光谱学与光谱分析 2019年第12期39卷 3761-3768页

作者：林剑远张长兴尤红建中国科学院大学工程科学学院北京100049 中国科学院上海技术物理研究所中国科学院空间主动光电技术重点实验室上海200083 中国科学院电子学研究所北京100190

水体辐射传输模型是水体光谱特性分析的理论基础,水体固有光学量由水体组成决定,与水体表面光场无关。基于统计的半经验算法虽然能获取指定区域水质参数反演结果,但是缺乏物理意义;基于生物光学模型的分析算法,针对城市河网内陆Ⅱ类水... 详细信息

水体辐射传输模型是水体光谱特性分析的理论基础,水体固有光学量由水体组成决定,与水体表面光场无关。基于统计的半经验算法虽然能获取指定区域水质参数反演结果,但是缺乏物理意义;基于生物光学模型的分析算法,针对城市河网内陆Ⅱ类水体光学特性复杂、空间分布异质性强、水体细小、流动性大等特点,利用高光谱数据,研究基于固有光学量的城市河网水质参数反演模型,对内陆城市浑浊水体光谱特性研究具有重大意义。提出了适用于内陆城市河网水体的改进QAA算法,以获取水体固有光学量,改进包括后向散射估计模型调整和参考波段优化两个方面;计算参考波段总吸收系数、颗粒物后向散射系数等固有光学量,得到浮游植物吸收系数和剔除纯水吸收系数;对浮游植物吸收系数最优波段比值与叶绿素a浓度进行线性回归分析,构建叶绿素a水质浓度反演模型,对剔除纯水吸收系数最优波段比值与悬浮物浓度线性回归分析,构建悬浮物水质浓度反演模型。针对内陆河网Ⅱ类水体,以典型的河网城市嘉兴市为研究区域,获取了研究区域航空高光谱数据,以及水质采样化验数据和水面以上光谱数据等地面准同步测量数据;利用QAA算法和IIMIW算法对实测水面以上光谱进行固有光学量反演,对比分析两个算法并结合城市河网水体特点,提出改进QAA算法;利用改进的QAA算法实现了研究区域水体的固有光学量反演,基于反演的水体固有光学量建立了叶绿素a浓度和悬浮物浓度两项水色参数定量反演模型,反演模型决定系数R^2分别为0.64和0.71;并用航空高光谱数据同步区域的4个地面样点实测数据,对反演结果进行验证分析。通过水质参数浓度反演值与实测值的对比,叶绿素a和悬浮物水质浓度反演的平均相对误差分别为9.2%和9.4%,反演得到的叶绿素a和悬浮物浓度分布图,也与城市河网的特点和实际情况相符,为城市河网水质监测提供方法和模型参考。

关键词：河网城市高光谱固有光学量改进QAA 水质反演

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Global view on virus infection in non-human primates and implications for public health and wildlife conservation

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Zoological Research 2021年第5期42卷 626-632页

作者： Zhi-Jin Liu Xue-kun Qian Min-Heng Hong Jia-Li zhang Da-Yong Li Tian-Han Wang Zuo-Min Yang Li-Ye zhang Zi-Ming Wang Hua-jian Nieke-Yue Fan Xiong-Fei zhang Meng-Meng Chen Wei-Lai Sha Christian Roos Ming Li College of Life sciences Capital Normal UniversityBeijing 100048China College of Life sciences Hebei UniversityBaodingHebei 071002China CAS key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyBeijing 100101China university of Chinese Academy of sciences Beijing 100049China College of Life sciences China West Normal UniversityNanchongSichuan 637009China College of Life sciences Qufu Normal UniversityQufuShandong 273100China Primate Genetics Laboratory German Primate CenterLeibniz Institute for Primate ResearchGoettingen 37077Germany State key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Gene Bank of Primates German Primate CenterLeibniz Institute for Primate ResearchGoettingen 37077Germany Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China

Viruses can be transmitted from animals to humans(and vice versa)and across animal *** such,host-virus interactions and transmission have attracted considerable ***-human primates(NHPs),our closest evolutionary relatives,are susceptible to human viruses and certain pathogens are known to circulate between humans and ***,we generated global statistics on virus infections in NHPs(VI-NHPs)based on a literature search and public data *** total,140 NHP species from 12 families are reported to be infected by 186 DNA and RNA virus species,68.8%of which are also found in humans,indicating high potential for crossing species boundaries.

关键词： species. primates attention

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Time-varying impact of political risk on copper prices

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Transactions of Nonferrous Metals Society of China 2021年第8期31卷 2532-2544页

作者： Jing TANG jian-bai HuANG Hong-wei zhang Yu-mei LuO School of Business Central South UniversityChangsha 410083China institute of Metal Resources Strategy Central South UniversityChangsha 410083China School of mathematics and statistics Central South UniversityChangsha 410083China

using the International Country Risk Guide(ICRG)index to represent countries’political risk,the time-varying effect of political risk on copper prices was examined based on the time-varying parameter structural vector autoregression with stochastic volatility(TVP-SVAR-SV)*** empirical results show that the impact of political risk on copper prices is time-varying and has tended to increase gradually in recent *** are significant country-level differences in the impact of political risk on copper *** risk has a stronger and longer-lasting impact on copper prices in exporting *** terms of risk sources,external and internal conflicts contribute most to international copper price fluctuations in the sample *** impact of political risk on copper prices reaches an extreme level during the international financial crisis,the European debt crisis,and the election of Donald Trump.

关键词： political risk copper prices time-varying impact TVP-SVAR-SV model

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6个芒果品种品质特性评价研究

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食品科技 2011年第9期36卷 65-69页

作者：张劲黄丽夏宁韦保耀滕建文广西大学轻工与食品工程学院南宁530004

对台农一号、紫花、桂七、凯特、马切苏和三年芒6个品种芒果原浆的色泽、口感滋味及物理特征进行了评价,分析了包括可溶性固形物、可滴定酸度、pH、总糖、胡萝卜素、抗坏血酸、黏度以及色泽等与芒果原浆品质特性相关的物理和生化指标。... 详细信息

对台农一号、紫花、桂七、凯特、马切苏和三年芒6个品种芒果原浆的色泽、口感滋味及物理特征进行了评价,分析了包括可溶性固形物、可滴定酸度、pH、总糖、胡萝卜素、抗坏血酸、黏度以及色泽等与芒果原浆品质特性相关的物理和生化指标。基于SPSS统计分析软件对测定指标进行了因子分析,比较了不同芒果品种品质特性的差异性,并与国外优良品种品质进行比较。结果表明,台农一号、凯特、马切苏口感品质较为适宜,马切苏和三年芒营养素含量最为丰富,凯特和紫花色泽品质较佳。中国芒果品种整体品质低于国外品种。

关键词：芒果品种品质特性因子分析

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