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| 1 | Annual temperatures during the last 2485 years in the mid-eastern Tibetan Plateau inferred from tree rings显示文摘By combining living trees and archaeological wood, the annual mean temperatures were reconstructed based on ring-width indices of the mid-eastern Tibetan Plateau for the past 2485 years. The climate variations revealed by the reconstruction indicate that there were four periods to have average tem- peratures similar to or even higher than that mean of 1970 to 2000 AD. A particularly notable rapid shift from cold to warm, we call it the 'Eastern Jin Event', occurred from 348 AD to 413 AD. Calculation re- sults show that the temperature variations over the mid-eastern Tibetan Plateau are not only repre- sentative for large parts of north-central China, but also closely correspond to those of the entire Northern Hemisphere over long time scales. During the last 2485 years, the downfall of most major dynasties in China coincides with intervals of low temperature. Compared with the temperature records in other regions of China during the last 1000 years, this reconstruction from the Tibetan Plateau shows a significant warming trend after the 1950s. | Hans W. LINDERHOLM | 2009 | Science China Earth Sciences2009，52，3： | 62 |
| 2 | 基于Petri网的服务组合故障诊断与处理显示文摘通过分析服务组合的故障需求,给出服务组合故障处理的框架.该框架采用Petri网来解决服务组合的错误发现及其处理问题.重点讨论了可用服务失败、组件失败及网络故障的情况,并相应地给出了服务组合故障模型.在此基础上对故障处理模型进行分析,给出服务组合故障处理正确性准则,并证明了其正确性.最后,采用CTL(computational tree logic)描述相关性质并提出验证服务组合故障分析的实施算法.仿真结果表明,该方法在处理服务组合故障时具有一定的优越性. | 范贵生 虞慧群 陈丽琼 刘冬梅 | 2010 | 软件学报2010，21，2： | 41 |
| 3 | 面向对象方法的时间序列MODIS数据湿地信息提取——以洞庭湖流域为例显示文摘以洞庭湖流域为研究区,对大范围湿地信息遥感提取方法进行了研究。先基于时间序列MODIS EVI及物候特征参数,通过J-M(Jeffries-Matusita distance)距离分析,构建了MODIS(250 m)最佳时序组合分类数据;其次,通过Johnson指数确定了最佳分割尺度,采用面向对象的遥感分类方法(Random tree分类器)提取了洞庭湖流域的湿地信息,并验证该方法的适用性。研究结果表明,基于时序数据与面向对象的Random tree分类的总体精度和Kappa系数分别为78.84%和0.71,较之基于像元的相同算法的总体分类精度和Kappa系数分别提高了5.79%和0.04。同时,基于面向对象方法的湿地整体的用户精度与生产者精度较基于像元方法分别提高了4.56%和6.21%,可有效提高大区域湿地信息提取的精度。 | 张猛 曾永年 朱永森 | 2017 | 遥感学报2017，21，3： | 39 |
| 4 | 一种基于K-D树优化的ICP三维点云配准方法显示文摘为提高三维点云数据配准精度和速度,提出一种基于K-D树优化的ICP三维点云配准方法,首先采用中心重合法实现点云数据的粗配准,然后利用K-D tree快速搜索最近点对改进传统ICP方法,完成三维点云数据精配准,该方法克服传统ICP算法中由于利用欧式距离来判断最近点所引起的工作量大、耗费时间多的缺陷,提高点云的配准速度。在此基础上利用斯坦福不同密度Bunny点云数据进行实验验证,结果表明在采用中心重合法实现三维点云粗配准的基础上,利用K-D tree优化ICP算法,能够提高点云配准的精度、速度和稳定性。 | 刘江 张旭 朱继文 | 2016 | 测绘工程2016，25，6： | 34 |
| 5 | 基于PATRICIA tree的汉语自动分词词典机制显示文摘分词词典是汉语信息处理系统的一个基本组成部分 ,其查询和更新效率将直接影响汉语信息处理系统的性能。本文采用PATRICIAtree的数据结构 ,设计了一种可以对词典词条进行快速查询、更新的分词词典机制 ,并从理论上初步分析了它的性能。最后通过实验 ,在时间效率上与逐字二分的分词词典机制进行了比较。结果表明 ,基于PATRICIAtree的分词词典机制具有更高的查询速度和更新效率 ,能满足大规模、开放文本处理系统的需求。 | 杨文峰 陈光英 李星 | 2001 | 中文信息学报2001，15，3： | 29 |
| 6 | The Chromosome-Level Reference Genome of Tea Tree Unveils Recent Bursts of Nonautonomous LTR Retrotransposons in Driving Genome Size Evolution显示文摘Dear Editor,The tea tree Camellia sinensis,a member of the genus Camellia in the Theaceae family,includes two major cultivated varieties,C.sinensis var.assamica(CSA\Assam type)and C.sinensis var.sinensis(CSS;Chinese type)(Ming and Bartholomew,2007).Due to the high economic importance of the tea tree,considerable efforts have been made to explore genetic basis of the biosynthesis of natural metabolites that determine health benefits and diverse tea flavors(Shi et al.,2011;Li et al.,2011;Li et al.,2015;Xia et aL,2017;Liu et al.,2019). | Qun-Jie Zhang Wei L i Kui Li Hong Nan Cong Shi Yun Zhang Zhang-Yan Dai Yang-Lei Lin Xiao-Lan Yang Yan Tong Dan Zhang Cui Lu Li-Ying Feng Chen-Feng Wang Xiao-Xin Liu Jian-An Huang Wen-Kai Jiang Xing-Hua Wang Xing-Cai Zhang Evan E.Eichler Zhong-Hua Liu and Li-Zhi Gao | 2020 | Molecular Plant2020，13，7： | 27 |
| 7 | Strong law of large numbers for Markov chains indexed by an infinite tree with uniformly bounded degree显示文摘In this paper,we study the strong law of large numbers and Shannon-McMillan (S-M) theorem for Markov chains indexed by an infinite tree with uniformly bounded degree.The results generalize the analogous results on a homogeneous tree. | HUANG HuiLin~1 YANG WeiGuo~(2+) 1 Department of Mathematics,Shanghai Jiaotong University,Shanghai 200240,China 2 Faculty of Science,Jiangsu University,Zhenjiang 212013,China | 2008 | Science China Mathematics2008，51，2： | 23 |
| 8 | On the combined effect of soil fertility and topography on tree growth in subtropical forest ecosystems—a study from SE China显示文摘Aims The aim of our research was to understand small-scale effects of topography and soil fertility on tree growth in a forest biodiversity and ecosystem functioning(BEF)experiment in subtropical SE China.Methods Geomorphometric terrain analyses were carried out at a spatial resolution of 5×5 m.Soil samples of different depth increments and data on tree height were collected from a total of 566 plots(667 m2 each).The soils were analyzed for carbon(soil organic carbon[SOC]),nitrogen,acidity,cation exchange capacity(CEC),exchangeable cations and base saturation as soil fertility attributes.All plots were classified into geomorphological units.Analyses of variance and linear regressions were applied to all terrain,soil fertility and tree growth attributes.Important Findings In general,young and shallow soils and relatively small differences in stable soil properties suggest that soil erosion has truncated the soils to a large extent over the whole area of the experiment.This explains the concurrently increasing CEC and SOC stocks downslope,in hollows and in valleys.However,colluvial,carbon-rich sediments are missing widely due to the convexity of the footslopes caused by uplift and removal of eroded sediments by adjacent waterways.The results showed that soil fertility is mainly influenced by topography.Monte-Carlo flow accumulation(MCCA),curvature,slope and aspect significantly affected soil fertility.Furthermore,soil fertility was affected by the different geomorphological positions on the experimental sites with ridge and spur positions showing lower exchangeable base cation contents,especially potassium(K),due to leaching.This geomorphological effect of soil fertility is most pronounced in the topsoil and decreases when considering the subsoil down to 50 cm depth.Few soil fertility attributes affect tree height after 1-2 years of growth,among which C stocks proved to be most important while pH_(KCl)and CEC only played minor roles.Nevertheless,soil acidity and a high proportion of Al on the exchange complex affected tree height even after only 1-2 years growth.Hence,our study showed that forest nutrition is coupled to a recycling of litter nutrients,and does not only depend on subsequent supply of nutrients from the mineral soil.Besides soil fertility,topography affected tree height.We found that especially MCCA as indicator of water availability affected tree growth at small-scale,as well as aspect.Overall,our synthesis on the interrelation between fertility,topography and tree growth in a subtropical forest ecosystem in SE China showed that topographic heterogeneity lead to ecological gradients across geomorphological positions.In this respect,small-scale soil-plant interactions in a young forest can serve as a driver for the future development of vegetation and biodiversity control on soil fertility.In addition,it shows that terrain attributes should be accounted for in ecological research. | Thomas Scholten Philipp Goebes Peter Kühn Steffen Seitz Thorsten Assmann Jürgen Bauhus Helge Bruelheide Francois Buscot Alexandra Erfmeier Markus Fischer Werner Härdtle Jin-Sheng He Keping Ma Pascal A.Niklaus Michael Scherer-Lorenzen Bernhard Schmid Xuezheng Shi Zhengshan Song Goddert von Oheimb Christian Wirth Tesfaye Wubet Karsten Schmidt | 2017 | Journal of Plant Ecology2017，10，1： | 22 |
| 9 | 基于Boosting Tree算法的测井岩性识别模型显示文摘使用Boosting Tree算法,以录井资料和测井资料为基础,优选出自然伽马、自然电位、冲洗带电阻率、侵入带电阻率、原状地层电阻率、密度、补偿中子、声波时差8个对岩性敏感度较高的测井属性,建立岩性识别模型。使用该方法对玛北油田岩石类型齐全的6号井的目的层岩性进行识别,正确率达到89.1%,优于决策树、支持向量机(SVM)等传统的机器学习方法。使用Boosting Tree算法对岩性进行识别也为测井解释提供了新的思路。 | 江凯 王守东 胡永静 浦世照 段航 王政文 | 2018 | 测井技术2018，42，4： | 21 |
| 10 | Island partition of the distribution system with distributed generation显示文摘In this paper, a novel optimum island partition model based on Tree Knapsack Problem (TKP) is presented for the distribution system integrated with distributed generation (DG), and a Depth-first Dynamic Programming Algorithm (DPA) is used to solve this model. With the considerations of the load priority, controlled/uncontrolled loads, and the constraints of power balance, voltage and equipment capacity, the model can meet the practical engineering requirements very well. The island partition problem of the distribution system integrated with multiple DGs is first decomposed into multiple TKPs, each of which is solved by DPA respectively. Then, the initial optimum island partition scheme is gained through an island combination procedure, and the final island partition scheme is obtained after feasibility checking and adjustment. Since the algorithm proposed owns the advantages of strong theoretical foundation and low computational complexity, it can find the approximate optimal solution within a limited time. The results of examples demonstrate the validity of the new model and algorithm. | WANG XuDong & LIN JiKeng* Key laboratory of Power System Simulation and Control of Ministry of Education, Tianjin University, Tianjin 300072, China | 2010 | Science China(Technological Sciences)2010，53，11： | 21 |
| 11 | FAULT TREE ANALYSIS OF SPONTANEOUS COMBUSTION OF SULPHIDE ORES AND ITS RISK ASSESSMENT显示文摘A logic fault tree of mine spontaneous combustion of sulphide ores was built by the fault tree analysis (FTA) based on a lot of mechanism investigation of sulphide ore spontaneous combustion in more than ten mines and review of a great amount of relevant | Wu Chao(Department of Resources Exploitation Engineering, Central South University of Technology, Changsha, 410083, China ) | 1995 | Journal of Central South University1995，7，2： | 21 |
| 12 | IPSMS:一个网络舆情监控系统的设计与实现显示文摘描述一个网络舆情监控系统IPSMS(Internet public sentiment monitoring system)。该系统试图将网络新闻及论坛、BBS上的帖子依关键词搜索,并依'事件'聚类,让管理者通过阅读事件可以了解正在发生或已经发生的事件,并提供自动持续追踪事件发展的功能,以协助管理者快速完整且全面地了解事件全貌。系统由网页抓取器、网页解析器及跟踪检测系统三部分组成。由于网络舆情的特点是数据量巨大,为了提高效率,系统采用了网页清理技术,并且在话题跟踪过程中使用了k-d tree方法。最后,对系统的未来工作进行了展望。 | 丁杰 徐俊刚 | 2010 | 计算机应用与软件2010，27，4： | 21 |
| 13 | 一种改进的基于PCA的ICP点云配准算法研究显示文摘三维点云配准是三维重建过程中的重要环节,ICP配准算法无法处理初始位姿相差较大的点云,结果可能陷入局部最优的问题。本文提出了一种改进的基于PCA的快速ICP匹配算法,通过对两组点云进行主成分求解,形成各自的PCA坐标系。对两组点云分别进行坐标系转换,通过主轴校正矩阵解决了PCA主轴反向问题;利用K-D tree快速搜索最近点改进传统ICP 方法,完成点云的快速精确配准。实验表明,该配准算法可以有效处理点云初始位置较差的情况,实现任意位姿关系下的两组点云的快速精确配准。 | 刘哲 周天 彭东东 冯晨 | 2019 | 黑龙江大学自然科学学报2019，36，4： | 19 |
| 14 | The Chromosome-Based Rubber Tree Genome Provides New Insights into Spurge Genome Evolution and Rubber Biosynthesis显示文摘The rubber tree,Hevea brasiliensis,produces natural rubber that serves as an essential industrial raw material.Here,we present a high-quality reference genome for a rubber tree cultivar GT1 using single-molecule real-time sequencing(SMRT)and Hi-C technologies to anchor the~1.47-Gb genome assembly into 18 pseudochromosomes.The chromosome-based genome analysis enabled us to establish a model of spurge chromosome evolution,since the common paleopolyploid event occurred before the split of Hevea and Manihot.We show recent and rapid bursts of the three Hevea-specific LTR-retrotransposon families during the last 10 million years,leading to the massive expansion by~65.88%(~970 Mbp)of the whole rubber tree genome since the divergence from Manihot.We identify large-scale expansion of genes associated with whole rubber biosynthesis processes,such as basal metabolic processes,ethylene biosynthesis,and the activation of polysaccharide and glycoprotein lectin,which are important properties for latex production.A map of genomic variation between the cultivated and wild rubber trees was obtained,which contains~15.7 million high-quality single-nucleotide polymorphisms.We identified hundreds of candidate domestication genes with drastically lowered genomic diversity in the cultivated but not wild rubber trees despite a relatively short domestication history of rubber tree,some of which are involved in rubber biosynthesis.This genome assembly represents key resources for future rubber tree research and breeding,providing novel targets for improving plant biotic and abiotic tolerance and rubber production. | Jin Liu Cong Shi Cheng-Cheng Shi Wei Li Qun-Jie Zhang Yun Zhang Kui Li Hui-Fang Lu Chao Shi Si-Tao Zhu Zai-Yun Xiao Hong Nan Yao Yue Xun-Ge Zhu Yu Wu Xiao-Ning Hong Guang-Yi Fan Yan Tong Dan Zhang Chang-Li Mao Yun-Long Liu Shi-Jie Hao Wei-Qing Liu Mei-Qi Lv Hai-Bin Zhang Yuan Liu Ge-Ran Hu-tang Jin-Peng Wang Jia-Hao Wang Ying-Huai Sun Shu-Bang Ni Wen-Bin Chen Xing-Cai Zhang Yuan-Nian Jiao Evan E.Eichler Guo-Hua Li Xin Liu Li-Zhi Gao | 2020 | Molecular Plant2020，13，2： | 15 |
| 15 | A novel image segmentation approach for wood plate surface defect classification through convex optimization显示文摘Detection of wood plate surface defects using image processing is a complicated problem in the forest industry as the image of the wood surface contains different kinds of defects. In order to obtain complete defect images, we used convex optimization(CO) with different weights as a pretreatment method for smoothing and the Otsu segmentation method to obtain the target defect area images. Structural similarity(SSIM) results between original image and defect image were calculated to evaluate the performance of segmentation with different convex optimization weights. The geometric and intensity features of defects were extracted before constructing a classification and regression tree(CART) classifier. The average accuracy of the classifier is 94.1% with four types of defects on Xylosma congestum wood plate surface: pinhole, crack,live knot and dead knot. Experimental results showed that CO can save the edge of target defects maximally, SSIM can select the appropriate weight for CO, and the CART classifier appears to have the advantages of good adaptability and high classification accuracy. | Zhanyuan Chang Jun Cao Yizhuo Zhang | 2018 | Journal of Forestry Research2018，29，6： | 14 |
| 16 | 区块链综述:技术与挑战显示文摘区块链技术被广泛认为是一个可以在数字空间中构建信任的系统技术,其主要特征包括去中心化、多副本冗余、防数据纂改、分布式环境下的建立共识等。区块链的相关应用如比特币、智能合约等逐步在不同的领域被采纳和推广。区块链的核心构建技术和理论,包括有链式安全存储、共识算法、对等网络、智能合约等。从区块链的参考技术架构、区块链的核心理论和技术、区块链典型系统三个方面讨论了现有的区块链技术,希望为相关研究提供有益的指导和借鉴。 | 王锡亮 刘学枫 赵淦森 王欣明 周子衡 莫泽枫 | 2018 | 无线电通信技术2018，44，6： | 14 |
| 17 | 基于近邻搜索的激光点云数据孤立噪点滤波研究显示文摘受仪器自身和测量环境等条件的影响,地面三维激光扫描仪获取的无序或者散乱点云中通常存在孤立的噪声点。针对孤立噪声点,使用k-d tree组织和管理点云数据,使其有序化;根据孤立噪声点与其k个最近邻点距离的正态统计分布特性,自动计算噪声滤除的阈值并滤除噪声。建筑物激光点滤除噪声的实验表明,文中方法能自动滤除孤立噪声点,滤噪阈值无需人工设置且精度与人机交互滤噪结果基本一致,能有效滤除无序点云的孤立噪声点。 | 张芳菲 梁玉斌 王佳 | 2018 | 测绘工程2018，27，11： | 14 |
| 18 | Complex Least Squares Adjustment to Improve Tree Height Inversion Problem in PolInSAR显示文摘At present,the principal data processing methods involving complex observations are based on two strategies according to characteristics of the observation process,i.e.,step-by-step and direct resolution.However,these strategies have some limitations,e.g.they cannot consider statistical observation error information,redundant observations and so on.This paper applies least squares methods to complex data processing to extend surveying adjustment theory from real to complex number space.We compared the two adjustment criteria for a complex domain in a quantitative way.In order to understand the effectiveness of complex least squares,tree height inversion from PolInSAR data is taken as an example.We firstly established both a complex adjustment function model and a stochastic model for PolInSAR tree height inversion,and then applied the complex least squares method to estimate tree height.Results show that the complex least squares approach is reliable and outperforms other classic tree height retrieval methods;the method is simple and easy to implement. | Jianjun ZHU Qinghua XIE Tingying ZUO Changcheng WANG Jian XIE | 2019 | Journal of Geodesy and Geoinformation Science2019，2，1： | 12 |
| 19 | An Embedded Feature Selection Method for Imbalanced Data Classification显示文摘Imbalanced data is one type of datasets that are frequently found in real-world applications, e.g., fraud detection and cancer diagnosis. For this type of datasets, improving the accuracy to identify their minority class is a critically important issue.Feature selection is one method to address this issue. An effective feature selection method can choose a subset of features that favor in the accurate determination of the minority class. A decision tree is a classifier that can be built up by using different splitting criteria. Its advantage is the ease of detecting which feature is used as a splitting node. Thus, it is possible to use a decision tree splitting criterion as a feature selection method. In this paper, an embedded feature selection method using our proposed weighted Gini index(WGI) is proposed. Its comparison results with Chi2, F-statistic and Gini index feature selection methods show that F-statistic and Chi2 reach the best performance when only a few features are selected. As the number of selected features increases, our proposed method has the highest probability of achieving the best performance. The area under a receiver operating characteristic curve(ROC AUC) and F-measure are used as evaluation criteria. Experimental results with two datasets show that ROC AUC performance can be high, even if only a few features are selected and used, and only changes slightly as more and more features are selected. However, the performance of Fmeasure achieves excellent performance only if 20% or more of features are chosen. The results are helpful for practitioners to select a proper feature selection method when facing a practical problem. | Haoyue Liu MengChu Zhou Qing Liu | 2019 | IEEE/CAA Journal of Automatica Sinica2019，6，3： | 11 |
| 20 | How do machine learning techniques help in increasing accuracy of landslide susceptibility maps?显示文摘Landslides are abundant in mountainous regions.They are responsible for substantial damages and losses in those areas.The A1 Highway,which is an important road in Algeria,was sometimes constructed in mountainous and/or semi-mountainous areas.Previous studies of landslide susceptibility mapping conducted near this road using statistical and expert methods have yielded ordinary results.In this research,we are interested in how do machine learning techniques help in increasing accuracy of landslide susceptibility maps in the vicinity of the A1 Highway corridor.To do this,an important section at Ain Bouziane(NE,Algeria) is chosen as a case study to evaluate the landslide susceptibility using three different machine learning methods,namely,random forest(RF),support vector machine(SVM),and boosted regression tree(BRT).First,an inventory map and nine input factors were prepared for landslide susceptibility mapping(LSM) analyses.The three models were constructed to find the most susceptible areas to this phenomenon.The results were assessed by calculating the receiver operating characteristic(ROC) curve,the standard error(Std.error),and the confidence interval(CI) at 95%.The RF model reached the highest predictive accuracy(AUC=97.2%) comparatively to the other models.The outcomes of this research proved that the obtained machine learning models had the ability to predict future landslide locations in this important road section.In addition,their application gives an improvement of the accuracy of LSMs near the road corridor.The machine learning models may become an important prediction tool that will identify landslide alleviation actions. | Yacine Achour Hamid Reza Pourghasemi | 2020 | Geoscience Frontiers2020，11，3： | 11 |
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