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    题名 作者 年代 出处 被引量
1Extrinsic harmful residues in Chinese herbal medicines: types,detection, and safety evaluation显示文摘Chinese herbal medicines(CHMs)are playing important roles in the treatment of diseases and human health care throughout the world.However,the extrinsic harmful residues have been threatening the therapies by destroying CHMs qualtiy which hinders the international trades of CHMs.This review summarized the extrinsic harmful residues contaminating CHMs in types,detection methods,national and international regulations,and made safety evaluations according to their contaminated levels,aiming to establish understanding among nations or organizations and provide references for the formulation or amendment of relative regulations.Cong-min Liu Jia-an Qin Xiao-wen Dou Mei-hua Yang Xiao-bo Sun 2018Chinese Herbal Medicines2018,10,2:13
2Chinese herbal medicine reduces mortality in patients with severe and critical coronavirus disease 2019: a retrospective cohort study显示文摘This study aimed to evaluate the efficacy of Chinese herbal medicine(CHM)in patients with severe/critical coronavirus disease 2019(COVID-19).In this retrospective study,data were collected from 662 patients with severe/critical COVID-19 who were admitted to a designated hospital to treat patients with severe COVID-19 in Wuhan before March 20,2020.All patients were divided into an exposed group(CHM users)and a control group(non-users).After propensity score matching in a 1:1 ratio,156 CHM users were matched by propensity score to 156 non-users.No significant differences in seven baseline clinical variables were found between the two groups of patients.All-cause mortality was reported in 13 CHM users who died and 36 non-users who died.After multivariate adjustment,the mortality risk of CHM users was reduced by 82.2%(odds ratio 0.178,95%CI 0.076–0.418;P<0.001)compared with the non-users.Secondly,age(odds ratio 1.053,95%CI 1.023–1.084;P<0.001)and the proportion of severe/critical patients(odds ratio 0.063,95%CI 0.028–0.143;P<0.001)were the risk factors of mortality.These results show that the use of CHM may reduce the mortality of patients with severe/critical COVID-19.Guohua Chen Wen Su Jiayao Yang Dan Luo Ping Xia Wen Jia Xiuyang Li Chuan Wang Suping Lang Qingbin Meng Ying Zhang Yuhe Ke An Fan Shuo Yang Yujiao Zheng Xuepeng Fan Jie Qiao Fengmei Lian Li Wei Xiaolin Tong 2020Frontiers of Medicine2020,14,6:10
3基于无人机LiDAR的天然林与人工林林隙提取显示文摘为研究主动遥感进行森林地物分类和林隙提取的效果,分别在天然林和人工林中比较了无人机激光雷达(LiDAR)数据的阈值法、逐像元法和面向对象法3种方法的分类精度和适用性。选取天然林(黑龙江省哈尔滨市帽儿山林场)和人工林(内蒙古自治区赤峰市旺业甸林场)两处试验区,应用阈值法、逐像元法和面向对象法3种方法,对两个试验区采集的无人机LiDAR数据进行林隙、非林隙、其他类型划分。研究结果表明,面向对象法在天然林和人工林试验区中的分类精度和Kappa系数均最高,天然林为82.43%、0.73,人工林为91.74%、0.88;逐像元法次之,天然林为76.62%、0.64,人工林为78.68%、0.68;阈值法的分类精度和Kappa系数差异较大,在天然林中的精度极低,为50.54%、0.27,人工林的精度较高,为79.12%、0.69。面向对象法和逐像元法在天然林和人工林普遍适用,均可以达到理想的分类精度和Kappa系数。阈值法在天然林的精度较低,更适合于人工林的分类,即林分高度趋于一致,且建筑、道路等其他类型干扰较少的区域。天然林的最佳分类方法为面向对象法,人工林的最佳分类方法为阈值法。毛学刚 杜子涵 刘家倩 陈树新 2020农业机械学报2020,51,3:8
4Review:Anticancer effects of Chinese herbal medicine,science or myth?显示文摘Currently there is considerable interest among oncologists to find anticancer drugs in Chinese herbal medicine (CHM). In the past, clinical data showed that some herbs possessed anticancer properties, but western scientists have doubted the scientific validity of CHM due to the lack of scientific evidence from their perspective. Recently there have been encouraging results, from a western perspective, in the cancer research field regarding the anticancer effects of CHM. Experiments showed that CHM played its anticancer role by inducing apoptosis and differentiation, enhancing the immune system, inhibiting angiogenesis, reversing multidrug resistance (MDR), etc. Clinical trials demonstrated that CHM could improve survival, increase tumor response, improve quality of life, or reduce chemotherapy toxicity, although much remained to be determined regarding the objective effects of CHM in human in the context of clinical trials. Interestingly, both laboratory experiments and clinical trials have demonstrated that when combined with chemotherapy, CHM could raise the efficacy level and lower toxic reactions. These facts raised the feasibility of the combination of herbal medicines and chemotherapy, although much remained to be investigated in this area.RUAN Wen-jing LAI Mao-de ZHOU Jian-guang 2006Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2006,7,12:7
5浅析电子书及其发展前景显示文摘作为网络出版物的主要组成部分 ,电子书的发展越来越受到人们的关注。本文就目前电子书的概念、特点、潜在的发展前景及影响制约的因素等问题加以分析和探讨。认为随着时间的推移和技术的进步 ,电子书因其自身的优点一定会赢得人们的亲睐 。季开祥 2003现代情报2003,23,11:7
6基于DOM及LiDAR的多尺度分割与面向对象林隙分类显示文摘为研究分割尺度对航空正射影像(DOM)与LiDAR数据协同面向对象林隙分割与分类的影响,以东北典型的天然次生林帽儿山实验林场东林施业区为试验区,对DOM与LiDAR数据进行多尺度分割与面向对象林隙分类。分割过程中,采用基于DOM分割、基于LiDAR数据分割、DOM&LiDAR协同分割3种分割方案。每种分割方案采用10种尺度。在每种尺度应用两种数据提取的光谱和高度两种特征,采用支持向量机分类器(SVM)进行林隙分类。研究结果表明:3种分割与分类方案分类精度随尺度的增大整体呈现下降的趋势,与ED3(Modified)趋势相反。基于LiDAR数据在尺度参数10获得了最优分割结果。在所有尺度上(10~100),基于LiDAR数据分割与分类精度高于其他两种数据源的分类精度,相比单独使用DOM优势更加明显。基于LiDAR数据分割与分类方案在尺度参数10时获得了最高分类精度(Kappa系数为80%)。3种分割与分类方案最优尺度的分类精度显著高于其他尺度分类精度。分割尺度对面向对象林隙分类结果有重要影响。毛学刚 侯吉宇 白雪峰 范文义 2017农业机械学报2017,48,9:7
7基于机载激光雷达的林隙结构参数提取显示文摘【目的】运用激光雷达技术识别提取林隙面积、边界木高和形状指数,为林隙结构参数调查提供技术支持。【方法】以机载激光雷达数据为数据源,以东北林业大学帽儿山实验林场内设置的5块林隙调查样地中的54个林隙为研究对象,通过对比普通克里金插值、反距离权重插值、样条插值、自然临近插值和局部多项式插值确定最优插值方法得到冠层高度模型,运用交替贯序滤波法对冠层高度模型进行林隙识别提取。【结果】通过对比5种插值方法的RMSE发现,普通克里金法适合插值DEM,反距离权重法适合插值DSM;采用交替贯序滤波法识别提取林隙时,林隙识别率为92.6%,运用配对检验法对提取的林隙面积、边界木高与野外调查数据进行检验,基于激光雷达技术提取的林隙面积和边界木高与野外实测值呈较强线性关系,R^2分别为0.983和0.737,其中提取的林隙面积与实测值平均相对误差为15.78%,林隙边界木高与实测值平均相对误差为11.94%。【结论】基于机载激光雷达数据采用交替贯序滤波能有效识别林隙且能准确提取其结构参数;坡度、坡位及冠层结构复杂程度都会影响冠层高度模型的插值精度;林隙面积提取受林隙边界形状和林层结构影响,林隙边界木高随着样地地形、坡度增加误差也随之增大。机载激光雷达技术具有获取地形和树木三维结构信息的优势,可为林隙识别及其结构参数提取提供新的遥感方法。李欢 李明泽 范文义 王斌 2018林业科学2018,54,10:6
8应用软件帮助文档的制作方法初探显示文摘介绍了应用软件帮助文档的主要格式,对当前流行的帮助文档制作工具进行了比较和总结,以QuickCHM为例归纳了联机帮助设计和制作的思想和方法,并对如何在用VB6.0开发的应用程序中引用帮助文件进行了讨论。刘兴权 杨海燕 陈奇 2005计算机时代2005,,7:5
9基于ICESat-GLAS波形估测平均树高的研究显示文摘以吉林省汪清林业局经营区域为例,基于星载激光雷达ICESat-GLAS回波参数,构建了平均树高回归模型,预估精度为84.05%;利用反距离加权法,对ICESat-GLAS光斑平均树高估测值进行差值运算,得到初始CHM(Canopy Height Model),实现了平均树高空间连续分布制图;再利用坡度校正和3×3移动窗口差分滤波平滑初始CHM,得到研究区平均树高修正CHM,预估精度达到91.52%。研究结果表明,坡度校正和移动窗口差分滤波方法能有效削弱坡度影响,剔除异常点,提高平均树高估测精度。刘美爽 邢艳秋 吴红波 尤号田 2014林业科学研究2014,27,3:4
10无线传感器网络路由协议成簇算法研究显示文摘阐述了无线传感器网络中路由协议成簇算法。在分析LEACH和SCRP的基础上,结合二者各自特点,提出了对SCRP的改进方案,并对实现算法进行了详细描述。由于考虑了网络负载平衡,该改进算法有利于提高WSN能量利用率,延长整个WSN网络的生存时间,拓展了基于簇的WSN路由协议的应用范围。芦东昕 侯晓东 2006华北电力大学学报(自然科学版)2006,33,4:4
11Object-based forest gaps classification using airborne LiDAR data显示文摘Object-based classification differentiates forest gaps from canopies at large regional scale by using remote sensing data. To study the segmentation and classification processes of object-based forest gaps classification at a regional scale, we sampled a natural secondary forest in northeast China at Maoershan Experimental Forest Farm.Airborne light detection and ranging(LiDAR; 3.7 points/m2) data were collected as the original data source and the canopy height model(CHM) and topographic dataset were extracted from the LiDAR data. The accuracy of objectbased forest gaps classification depends on previous segmentation. Thus our first step was to define 10 different scale parameters in CHM image segmentation. After image segmentation, the machine learning classification method was used to classify three kinds of object classes, namely,forest gaps, tree canopies, and others. The common support vector machine(SVM) classifier with the radial basis function kernel(RBF) was first adopted to test the effect of classification features(vegetation height features and some typical topographic features) on forest gap classification.Then the different classifiers(KNN, Bayes, decision tree,and SVM with linear kernel) were further adopted to compare the effect of classifiers on machine learning forest gaps classification. Segmentation accuracy and classification accuracy were evaluated by using Mo¨ller's method and confusion metrics, respectively. The scale parameter had a significant effect on object-based forest gap segmentation and classification. Classification accuracies at different scales revealed that there were two optimal scales(10 and 20) that provided similar accuracy, with the scale of 10 yielding slightly greater accuracy than 20. The accuracy of the classification by using combination of height features and SVM classifier with linear kernel was91% at the optimal scale parameter of 10, and it was highest comparing with other classification classifiers, such as SVM RBF(90%), Decision Tree(90%), Bayes(90%),or KNN(87%). The classifiers had no significant effect on forest gap classification, but the fewer parameters in the classifier equation and higher speed of operation probably lead to a higher accuracy of final classifications. Our results confirm that object-based classification can extract forest gaps at a large regional scale with appropriate classification features and classifiers using LiDAR data. We note, however, that final satisfaction of forest gap classification depends on the determination of optimal scale(s) of segmentation.Xuegang Mao Jiyu Hou 2019Journal of Forestry Research2019,30,2:3
12SrTiO_3纳米四方片状晶体的自组装行为及向立方晶体的转变显示文摘采用复合氢氧化物媒介法(CHM),以SrCO3和TiO2为原料在200℃、48h的生长条件下合成了立方相SrTiO3纳米晶体,它由大量的平行四方片层自组装成为长约500-800nm、宽约100-150nm的弯曲条状.生长时加入少量水可以改变晶体的形状得到尺寸略大的立方SrTiO3颗粒.探讨了CHM法制备纳米SrTiO3粉体的形成机理,指出SrTiO3纳米条的生长经过了'溶解→均相成核→片状晶体的生长→片层自组装'四个过程,此外分析了水在CHM方法中对晶体生长产生的影响.苗静 胡陈果 熊玉峰 韩向宇 奚伊 2007物理化学学报2007,23,10:3
133D facial motion tracking by combining online appearance model and cylinder head model in particle filtering显示文摘A 3D facial motion tracking approach has been proposed based on the incorporation of online appearance model(OAM)and cylinder head model(CHM)in the framework of particle filtering.1)For the construction of OAM,multi-measurements are infused to reduce the influence of lighting and person dependence.2)The global motion acquired from CHM fitting is set as the initialization of OAM fitting,and the fitting result is set as the initialization of CHM in the next frame.3)Motion filtering is applied with particle filter combined with local optimization and improved resampling.Objective between subjects evaluations show that our approach is fit to track facial motions.YU Jun WANG ZengFu 2014Science China(Information Sciences)2014,57,2:3
14Easy CHM——中小型图书馆电子图书制作之利器显示文摘分析目前图书馆数字化工作的现状及图书馆数字化管理软件的应用情况,侧重介绍EasyCHM电子图书制作软件的功能及其应用,旨在为中小型图书馆数字化工作拓展思路。方方 2005上海高校图书情报工作研究2005,15,3:2
15基于机载激光雷达冠层高度模型的小班区划显示文摘[目的]探究如何有效利用机载激光雷达冠层高度模型(CHM)自动区划小班,提高小班区划工作效率。[方法]在高光谱影像树种信息的辅助下,使用机载激光雷达数据生成的CHM进行两种空间尺度的分割和优化来自动区划小班。先对1 m空间分辨率CHM数据进行过分割,再对降尺度处理并平滑后的5 m空间分辨率CHM数据进行欠分割,结合两种尺度分割结果并优化得到最终区划结果。将自动区划结果与人工区划小班、数字正射影像(DOM)屏幕勾绘小班以及主伐作业小班为三类参考小班对比,采用最终测量精度(UMA)准则的圆度(RO),紧致度(CO),形状指数(SI),最小包络圆短半径(RE),椭圆度(EF)和形状因子(P2A)8个指标,及自动区划小班与参考小班的交并比(IOU)指标,定量评价自动区划小班边界勾绘的准确程度。并利用样地实测数据和CHM数据计算自动区划结果平均胸径、平均树高和冠层平均高的可解释性方差,验证自动区划结果的内部一致性和外部差异性精度。[结果]自动区划结果与参考小班的UMA形状、面积等特征较接近,与人工区划小班最相近。自动区划小班与人工区划、屏幕勾绘、主伐作业小班交并比大于70%的比例分别为46%,37%,43%,交并比大于50%的比例分别为61%,54%,55%。自动区划结果平均胸径可解释性方差为97%,平均树高可解释性方差为98%,和人工区划小班相同,说明其内部一致性高且和相邻小班差异大。冠层平均高可解释性方差为84.81%,比人工区划小班提高了1.77%。[结论]利用两种空间尺度的CHM与高光谱树种分类图的分割和优化方法自动区划的小班在内部一致性及边界的精准度方面有明显优势,更符合小班边界处林木的分布情况,小班边界准确,且工作效率高,有助于森林的精细化管理。熊昊 庞勇 荚文 李春干 2022林业科学研究2022,35,2:2
16林隙主被动遥感协同自动识别显示文摘【目的】研究林隙主被动遥感协同自动识别方法,为进一步量化林隙特征提供技术支持。【方法】以真彩色航空正射影像(0.2 m)和机载Li DAR(3.7点·m-2)为主被动遥感数据源,选取东北典型天然次生林——帽儿山实验林场东林施业区为研究区进行面向对象林隙识别。在面向对象分类过程中,通过对比3种分割方案(航空影像分割、Li DAR数据分割、航空影像&Li DAR协同分割)、10种尺度(10~100,步长为10)确定最优分割方案及尺度参数。在最优分割结果基础上应用航空影像的光谱特征、Li DAR数据提取的高度特征及共同特征,应用支持向量机分类器(SVM)进行林隙识别。【结果】3种分割方案的最优尺度均为20;所有尺度均是基于Li DAR数据分割ED3modified(0.52±0.11)低于基于航空影像分割(0.58±0.07)与航空影像&Li DAR协同数据分割(0.58±0.07)。在Li DAR数据最优尺度(20)下,采用光谱和高度共同特征的主被动识别与单独采用光谱特征的主动识别及单独使用高度特征的被动识别相比,分类精度分别提高36.71%和8.17%。【结论】3种分割方案中,基于Li DAR数据分割结果最好;使用主被动遥感协同自动识别进行林隙分类时精度最高(OA=87.73%,Kappa=0.81)。毛学刚 侯吉宇 范文义 2017林业科学2017,53,11:2
17无人机可见光遥感在普洱市森林资源监测中的应用显示文摘选取部分云南省普洱市2018年森林监测变化图斑,以华测P316组合翼无人机进行拍摄。对拍摄的照片数据利用Pix4Dmapper软件进行处理和三维重建,最终输出数据DOM、DEM、DSM和点云成果数据。利用ArcMap和Lidar360软件分别对栅格和点云成果数据进行处理和分析,研究其在森林资源监测中的应用。内容包括森林增量郁闭度计算,森林减量是否符合用地和采伐范围,立地因子中地貌、坡度、坡向的获取,林分因子中株数、树高、冠幅的获取以及测区的3D展示等。结果表明,无人机影像分辨率可达到肉眼近地观测精度,可采集部分立地因子和林分因子数据在替代人工现地调查中提高了调查工作效率。目前尚存在无人机续航时间不足,不适宜于大面积普查,且野外调查成本较高等问题。下一步需对其应用于森林蓄积量估算、获取测区多光谱信息,评估测区植被生长状态及森林健康状况监测等方面进一步研究。冷鸿天 杨雨渐 王海波 李元杰 冷天熙 马俊华 吴颜奎 2022林业调查规划2022,47,1:1
18森林经营空间规划软件联机帮助系统制作问题的解决方案显示文摘介绍软件联机帮助系统制作的方法,以森林经营空间规划软件为例,用Quick Chm开发帮助系统。CHM是目前流行的帮助文件格式,集各种优点于一体,将文字、声音、图像和动画等内容表现得淋漓尽致,可以用来制作软件说明书、产品介绍和学习教程等,能够为用户更好的使用软件提供一个有效途径,对软件的推广应用有着积极的作用。在制作过程中,遇到文字和图像不能按预定样式显示等问题,经过探索,多方寻找解决途径,最终成功地解决这些问题。张舟 罗传文 柴造坡 田爽 2009森林工程2009,25,3:1
19A Key Model: Translational Medicine in Research of Herbal Medicines显示文摘Chang-Xiao Liu 2014Chinese Herbal Medicines2014,6,2:1
20把课件做成CHM帮助文件风格显示文摘衡量一个教师教学水平的高低,对现代化教育教学手段的运用已成为一个非常重要的方面,教师制作多媒体教学课件已司空见惯了,由于高校教师教学、科研任务比较重,没有太多的时间去学习、钻研那些较难、较专业的多媒体制作工具的使用。于是,简单、易学、易用的PowerPoint成为了大多数教师一种理想的课件制作工具和现代化教学的重要手段。利用PowerPoint可以非常方便地插入各种文字,绘制图形,加入图像、声音、动画、视频影像等各种媒体信息,并根据需要设计各种演示效果,而且还可以非常方便地将每一种媒体超级链接到它的演示文稿中,丰富课件的内容和形式。苏艳艳 2004教育与职业2004,,27:1
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