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面向期刊评价的s指数构造及实例研究
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作者 朱雯 陈荣 刘颖 《中国科技期刊研究》 CSSCI 北大核心 2019年第2期189-196,共8页
【目的】探讨基于被引频次的sc指数和基于下载频次的sd指数在多学科期刊评价中的应用情况。【方法】利用中国知网数据库,以2011-2015年理、工、农、医、社会科学五大学科期刊的下载频次和被引频次为基础,构造期刊sd指数与sc指数,比较201... 【目的】探讨基于被引频次的sc指数和基于下载频次的sd指数在多学科期刊评价中的应用情况。【方法】利用中国知网数据库,以2011-2015年理、工、农、医、社会科学五大学科期刊的下载频次和被引频次为基础,构造期刊sd指数与sc指数,比较2011-2015年不同学科样本期刊的sd指数、sc指数的相关性变化情况以及与其他期刊评价指标的关系。【结果】与h指数相比,s指数更适合综合评价期刊的影响力;2011-2015年理、工、农、医学科样本期刊的sd指数、sc指数相关性高于社会科学,各学科在2013年和2014年相关系数波动较大;除社会科学学科外,2011-2015年其余学科样本期刊的sd指数、sc指数与其他期刊评价指标的相关性相差不大。【结论】s指数作为期刊评价指标具有一定的合理性;在期刊评价中需要考虑不同时间、不同学科期刊的下载频次和被引频次的关系。 展开更多
关键词 s指数 H指数 G指数 r指数 期刊评价
Assessing the oscillation of channel geometry and meander migration cardinality of Bhagirathi River,West Bengal,India
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作者 Rakhohori Bag Ismail Mondal Jatisankar Bandyopadhyay 《地理学报:英文版》 SCIE CSCD 2019年第4期613-634,共22页
Lateral migration of the Bhagirathi River temporally creates unavoidable geomorphic hazards in West Bengal,India.The Bhagirathi River flows SW for-67.30 km betwee n the confluenee point of Ajay and Jalangi rivers in E... Lateral migration of the Bhagirathi River temporally creates unavoidable geomorphic hazards in West Bengal,India.The Bhagirathi River flows SW for-67.30 km betwee n the confluenee point of Ajay and Jalangi rivers in East Burdwan and Nadia districts of West Bengal.The course of Bhagirathi is notably migration prone and cultivates problematic changes along its course over time.In the study,we have looked into its migration tendency and unpredictability for past 238 years and then predicted the lateral shifting of river centerline using temporal satellite imageries-Landsat-5(TM)of 1987(8,December),1995(28,January),2005(7,January)and LISS-IV satellite imagery(2017,5 January);SOI Toposheet-1968-1969(79A/2,79A/3,79A/6 and 79A/7)and RennelPs map of 1779.Other highlights are the quest of fluvial features,oxbow lakes,mid-channel bars,channel migration rate,meander geometry,channel sinuosity in different parts of river course and the parts that experience intensive bank erosion.The entire river course has been subdivided into three segments;viz.reaches A,B and C.Investigation displays that degree of sinuosity decreases from its anterior course(1968)to the existing course(2017).Reach-specific outputs display that reach B is highly sinuous(SI value 1.94 in 2017)and SI increases temporarily,whereas for reaches A and C it decreases with time.The rate of migration is higher in reach B than that in reaches C and A.The study displays a notably decreasing trend of migration in comparison with its previous lateral migration and shows that the migration nature over time is intensively inconsistent and unpredictable except very few portions of the river course.The nature of deposition within the river channel shows an unstable behavior during the entire period of the study.Meander geometry depicts a rapid change of river course innate to meander bends and shows a higher rate of migration by meander loop cut-off rather than lateral migration that reflects the inconsistency,erosion vulnerability and unpredictable nature of migration.Th 展开更多
关键词 channel GEOMETRY sinuosity INDEX BRAIDING INDEX MEANDER GEOMETRY radius of curvature bend TIGHTNESS INDEX linear regression GIS
Wiener Index, Hyper-Wiener Index, Harary Index and Hamiltonicity Properties of graphs 预览
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作者 YU Gui-dong REN Li-fang LI Xing-xing 《高校应用数学学报:英文版(B辑)》 SCIE CSCD 2019年第2期162-172,共11页
In this paper, in terms of Wiener index, hyper-Wiener index and Harary index, we first give some sufficient conditions for a nearly balance bipartite graph with given minimum degree to be traceable. Secondly, we estab... In this paper, in terms of Wiener index, hyper-Wiener index and Harary index, we first give some sufficient conditions for a nearly balance bipartite graph with given minimum degree to be traceable. Secondly, we establish some conditions for a k-connected graph to be Hamilton-connected and traceable for every vertex, respectively. 展开更多
关键词 WIENER INDEX Hyper-Wiener INDEX Harary INDEX TRACEABLE Hamilton-connected TRACEABLE for EVERY VERTEX
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钛冶金数据库条目性能优化设计研究 预览
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作者 马力 唐晓宁 +2 位作者 贺韬 谢刚 张彬 《矿冶》 CAS 2019年第1期50-53,共4页
钛冶金数据库是基于传统数据库软件开发的,其中最重要的一部分就是各种钛冶金数据的数学计算模型。钛化合物的热力学计算数据存储形式复杂、计算过程繁琐,查询和分析计算速度都受到数据库性能的影响。为此把数据库索引建立在基础数据库... 钛冶金数据库是基于传统数据库软件开发的,其中最重要的一部分就是各种钛冶金数据的数学计算模型。钛化合物的热力学计算数据存储形式复杂、计算过程繁琐,查询和分析计算速度都受到数据库性能的影响。为此把数据库索引建立在基础数据库上,成为索引数据库,使数据索引单独存放在该数据库中。索引数据库可以按照经济性能的比较,规划成标准大小的索引数据库,新增数据根据自身数据特点形成新的索引加入到索引数据库中,这样就利用已有数据库的处理能力对条目性能进行了优化,大大提高了钛冶金数据库的数据检索效率。 展开更多
关键词 钛冶金数据库 数据条目 索引 索引数据库 索引生产
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Remote Sensing Monitoring of Surface Characteristics in the Badain Jaran, Tengger, and Ulan Buh Deserts of China 预览
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作者 LIU Qingsheng LIU Gaohuan +1 位作者 HUANG Chong LI He 《中国地理科学:英文版》 SCIE CSCD 2019年第1期151-165,共15页
Deserts and sandy land in northern China are very susceptible to sandy desertification and are the main source of sand-dust storms of Asian dust. However, because of the complex factors involved, descriptions of the r... Deserts and sandy land in northern China are very susceptible to sandy desertification and are the main source of sand-dust storms of Asian dust. However, because of the complex factors involved, descriptions of the relationship between sandy desertification and surface characteristics in these regions are lacking. We monitored the surface characteristics and their changes in time using information about soil, vegetation, and landforms in the Badain Jaran Desert(BJD), Tengger Desert(TD), and Ulan Buh Desert(UBD) in the northern China. The monitoring was done using tasseled cap angle(TCA), disturbance index(DI), and topsoil grain size index(TGSI) from Moderate Resolution Imaging Spectroradiometer(MODIS) images combined with a decision tree classification. Results showed that the TD had higher topsoil fine sand content, and the ratio of non-vegetated to vegetated areas was similar with that in the UBD. Northeast-southwest coarse sand dunes with thin interdune(NECTI) dominated the BD, fine sand dunes(FSD) dominated the TD, and a combination of northeast-southwest coarse sand dunes with wide interdune(NECWI) and northwest-southeast coarse sand dunes with wide interdune(NWCWI) dominated the UBD. From 2000 to 2015, in the BJD the area of the NECTI, non-sand dune(Non) and potential sand sources(PSS) increased, whereas the area of the NECWI, FSD and NWCWI decreased, indicating a improve process in the BJD. In the TD, the area covered by Non increased, whereas the area covered by PSS, NECWI, NECTI, FSD, and NWCWI decreased from 2000 to 2015. The area covered by the various surface characteristic types fluctuated annually in the UBD from 2000 to 2015. Changes in surface characteristics reflect the combined effects of natural conditions and human activity. The findings of our study will assist scientists and policy makers in proposing different management techniques to combat sandy desertification for the different surface characteristics of these regions. 展开更多
关键词 surface characteristics MODIS DESERT tasseled CAP angle DISTURBANCE INDEX TOPSOIL GRAIN size INDEX
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Durability classification of red beds rocks in central Yunnan based on particle size distribution and slaking procedure
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作者 ZHU Jun-jie DENG Hui 《山地科学学报:英文版》 SCIE CSCD 2019年第3期714-724,共11页
Moisture induced disintegration of soft rock in Red Beds is common all over the world. The slake durability index test is most useful to quantify durability of the soft rocks. Based on a series of slaking test, this a... Moisture induced disintegration of soft rock in Red Beds is common all over the world. The slake durability index test is most useful to quantify durability of the soft rocks. Based on a series of slaking test, this article aims to develop a durability classification involving particle size and slaking procedure. To describe the slaking procedure in detail,the Relative Slake Durability Index(Idi) is proposed. The Idi is the percentage ratio of the ith weight of oven-dry retained portion to the(i-1)th weight of ovendry retained portion. Results show that the Idi of samples have a large difference in certain slaking procedure, whereas the traditional Durability Slake Index(Id) is almost constant. Considering this limitation of Id in durability classification, an advanced classification by applying the Idi and disintegration ratio(DR) is further established in this article. Compared to the durability classification based on Slake Durability Index(Id), the new classification accounts for the particle size of the slaked material and the slaking procedure, so it provides a better measure of the degree of slaking. The classification recommended in this article divide the slake durability into three classes(i.e., low, medium and high class). Furthermore, it divides both the low class and the medium class into 3 subclasses. 展开更多
关键词 Slaking test DURABILITY CLASSIFICATION RELATIVE DURABILITY INDEX DURABILITY INDEX Disintegrate rate
土地整理项目重估指标体系研究——以烟台市牟平区为例 预览
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作者 张贵军 姜凌燕 夏艳玲 《科学技术创新》 2019年第23期5-6,共2页
本文针对烟台市牟平区土地整理项目实际情况,采用多因素综合评定法对整理后项目区土地进行质量评价,构建土地质量重估评价指标体系,并应用AHP法进行指标权重的确定,以保证评价结果的科学性,为该地区土地整理项目土地质量评价提供支持。
关键词 土地整理 重估 指标 权重
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1961—2016年祁连山区季节性干旱综合指数特征分析 预览
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作者 郭小芹 罗永忠 《气象与环境学报》 2019年第1期88-93,共6页
采用Z指数和熵权理论,构建了干旱综合指数作为干旱强度评价标准,对祁连山区季节性干旱特征及其空间分布规律进行了深入剖析。结果表明:1961—2016年季节性干旱强度普遍减弱,其中春秋两季显著减弱,夏季明显减弱;尽管20世纪60—70年代、9... 采用Z指数和熵权理论,构建了干旱综合指数作为干旱强度评价标准,对祁连山区季节性干旱特征及其空间分布规律进行了深入剖析。结果表明:1961—2016年季节性干旱强度普遍减弱,其中春秋两季显著减弱,夏季明显减弱;尽管20世纪60—70年代、90年代为季节性干旱频发与重发时段,但从2000年以来夏旱与冬旱却比较频繁,不容忽视。干旱强度由强到弱依次为冬季、夏季、春季和秋季,冬季干旱程度最强;在干旱波动性上秋季最强,冬季次之,春季最弱。春夏秋三季南侧比北侧干旱,冬季北侧比南侧干旱,其中冬季干旱范围最为广泛,尤以酒泉为中心的北侧区域最为显著。在研究时段内祁连山南北两侧干旱强度逐渐减弱,南侧明显减弱,枯草期干旱强度减弱程度尤为显著。本研究为祁连山区干旱评价提供了参考依据。 展开更多
关键词 Z指数 熵权赋值 干旱综合指数 季节性干旱
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Blessing and a curse of outpatient management of delayed graft function 预览
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作者 Justin W Blazel Jennifer A Turk +1 位作者 Brenda L Muth Sandesh Parajuli 《世界移植杂志》 2019年第4期58-61,共4页
Delayed graft function (DGF) is a common complication occurring most often after deceased donor kidney transplant with several donor characteristics as well as immunologic factors that lead to its development post-tra... Delayed graft function (DGF) is a common complication occurring most often after deceased donor kidney transplant with several donor characteristics as well as immunologic factors that lead to its development post-transplant.These patients require dialysis and close kidney function monitoring until sufficient allograft function is achieved.This has resulted in limited options for DGF management,either prolonged hospitalization until graft function improves to the point where dialysis is no longer needed or discharge back to their home dialysis unit with periodic follow up in the transplant clinic.DGF is associated with a higher risk for acute rejection,premature graft failure,and 30-d readmission;therefore,these patients need close monitoring,immunosuppression management,and prompt allograft biopsy if prolonged DGF is observed.This may not occur if these patients are discharged back to their home dialysis unit.To address this issue,the University of Wisconsin-Madison created a clinic in 2011 specialized in outpatient DGF management.This clinic was able to successfully reduce hospital length of stay without an increase in 30-d readmission,graft loss,and patient death. 展开更多
关键词 Delayed graft function KIDNEY transplantation IMMUNOSUPPRESSION Acute rejection KIDNEY DONOR profile INDEX KIDNEY DONOR risk INDEX Dialysis
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The Status Assessment and Preliminary Risk Assessment of Total Mercury in Sediments from Middle and Lower Reaches of the Yarlung Zangbo River 预览
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作者 Qin Dongli Li Lei +6 位作者 Wu Song Wang Nianmin Wang Peng Chen Zhongxiang Ma Bo Bai Shuyan Gao Lei 《气象与环境研究:英文版》 CAS 2019年第3期84-89,共6页
The occurrence and accumulation of total mercury (T-Hg) in sediments collected from the Yarlung Zangbo River (YLZB),the Lhasa River,the Niyang River and the Palongzangbu River were analyzed and the soil samples simult... The occurrence and accumulation of total mercury (T-Hg) in sediments collected from the Yarlung Zangbo River (YLZB),the Lhasa River,the Niyang River and the Palongzangbu River were analyzed and the soil samples simultaneously collected from the bank were employed as control.Meanwhile,pollution status and potential ecological risk of Hg were calculated and assessed using index of geoaccumulation ( I geo ) and potential ecological risk assessment method (Er) in this study.The results showed that the T-Hg concentrations in sediments at eight sections of YLZB ranged from 4.23 to 48.1 μg/kg with mean concentration of 25.1 μg/kg,which was higher than background Hg value of soils in Tibet.T-Hg concentrations in sediments at three typical segments of YLZB were all significantly higher than those in soils collected from its bank (P<0.05).The Igeo and E r indexes revealed that the T-Hg pollution levels were slight pollution in two sections and moderate ecological risk in six sections of YLZB.Hg pollution risks also existed in the sediments of partial sections of the Lhasa River and the Niyang River,and slightly moderate Hg contamination with high ecological risk was presented in Lhasa urban district.The level of Hg in sediments of YLZB showed a notable spatial distribution characteristic with a trend of increasing firstly and then declining.Human activities played an important role in increasing Hg content in sediments of the river. 展开更多
关键词 The Yarlung Zangbo RIVER Total MERCURY Sediment INDEX of geoaccumulation Potential ecological risk INDEX
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Development unit division and favorable area evaluation for joint mining coalbed methane 预览
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作者 YANG Zhaobiao LI Yangyang +6 位作者 QIN Yong SUN Hansen ZHANG Ping ZHANG Zhengguang WU Congcong LI Cunlei CHEN Changxiao 《石油勘探与开发:英文版》 2019年第3期583-593,共11页
Based on the productivity equation of coalbed methane (CBM) well, considering the impact of coal reservoir reformability on gas well productivity, the main production layer optimization index in the “three-step metho... Based on the productivity equation of coalbed methane (CBM) well, considering the impact of coal reservoir reformability on gas well productivity, the main production layer optimization index in the “three-step method” of optimal combination of production layers is corrected, and then the CBM production layer potential index is introduced to evaluate favorable areas for commingled multi-coal seam production. Through analysis of the key parameters of coal reservoirs affecting the CBM productivity index, a development unit division method for areas with multi-coal seams is established, and a quantitative grading index system is proposed. On this basis, the evaluation process of CBM development favorable area is developed: the mature 3-D modeling technology is used to characterize the reservoir physical properties of multi-coal seams in full-scale;the production layer potential index of each grid is calculated, and the production layer potential index contour under single-layer or commingled multi-layer production are plotted;according to the distribution of the contour of production layer potential index, the quantitative index of CBM development unit is adopted to outline the grade I, II, III coal reservoir distribution areas, and thus to pick out the favorable development areas. The practical application in the Yuwang block of Laochang in Yunnan proved that the favorable area evaluation process proposed can effectively overcome the defects of selecting favorable development areas only relying on evaluation results of a major coal seam pay, and enhance the accuracy of the evaluation results, meeting the requirements of selecting favorable areas for multi-coal seam commingled CBM production. 展开更多
关键词 coalbed methane reservoir physical property JOINT MINING production layer potential INDEX DEVELOPMENT unit DIVISION quantitative INDEX favorable area EVALUATION
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Usage patterns of emergency medical services in Korea: analysis of patient flow
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作者 Mira Oh Jae Hyeon Lee +3 位作者 Byoung Uk Jeon Tae Oh Jeong Tag Heo Sungmin Lee 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第3期259-268,共10页
Background:This study used the National Emergency Department Information System (NEDIS) data to analyze the flow of emergency and critical emergency patients and to identify the patterns of emergency medical service u... Background:This study used the National Emergency Department Information System (NEDIS) data to analyze the flow of emergency and critical emergency patients and to identify the patterns of emergency medical service usage in Korea.Methods:The relevance index (RI) and commitment index (CI) were calculated from the 2016 NEDIS data. In this study, the number of clusters was determined using NbClust, and cluster analysis was used to analyze the usage patterns of emergency and critical emergency patients.Results:The RI and CI were calculated using 8,389,766 cases of 214 districts. The results of the RI and CI suggested that there were 3 types of clusters among the emergency patients. In Cluster 1, 54 districts (25.2%) had low RI and high CI, and it was of outflow type. Cluster 2 was categorized as the influx-type in 58 districts (27.1%) irrespective of RI and low CI. Cluster 3 was categorized as the self-sufficient type found in 102 districts (47.7%), with high RI and high CI. The cluster analysis of the critical emergency patients was divided into 2 types. Cluster 1 was categorized as outflow type with high CI found in 129 districts (60.3%), while Cluster 2 was categorized as inflow type with low CI found in 85 districts (39.7%).Conclusions:This study elucidates the regional status of usage patterns of emergency and critical emergency patients in Korea. This study might serve as a basis for the establishment and selection of emergency medical service areas and vulnerable emergency medical service areas. 展开更多
关键词 CLUSTERING COMMITMENT INDEX EMERGENCY DEPARTMENT National EMERGENCY DEPARTMENT Information System RELEVANCE INDEX
Study on the Difference of Body Mass Index and Insulin Sensitivity Index in Salt-sensitive Hypertension Patients of Different Traditional Chinese Medicine Syndrome Types 预览
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作者 褚瑜光 胡元会 《世界中西医结合杂志(英文)》 2019年第2期20-25,共6页
OBJECTIVE: To explore the difference of body mass index(BMI) and insulin sensitivity index(ISI) in saltsensitive hypertension patients of different traditional Chinese medicine(TCM) syndrome types, so as to elucidate ... OBJECTIVE: To explore the difference of body mass index(BMI) and insulin sensitivity index(ISI) in saltsensitive hypertension patients of different traditional Chinese medicine(TCM) syndrome types, so as to elucidate the effect of the distribution of each syndrome on the degree of insulin resistance in salt-sensitive hypertension patients. METHODS: A total of 131 patients with salt-sensitive hypertension were included in the study. Factor analysis and cluster analysis were used to study the characteristics of TCM viscera, syndrome elements and syndrome differentiation. Furthermore, the following parameters were observed and corresponding differences were analyzed, including BMI, waist circumference, abdominal circumference, neck circumference and insulin sensitivity index among group s of different TCM syndrome types. RESULTS: There were 131 cases of saltsensitive hypertension. The results of factor analysis showed that the total variance contribution of F1-5 common factors was 75.8%. According to the pattern differentiation of zang-fu organs, a basic theory of traditional Chinese medicine(TCM), the main zang-fu organs involved in the five common factors are: liver, spleen, and kidney.The main syndrome factors that had been extracted include yin de?ciency, ?re, qi stagnation, yang hyperactivity,dampness, phlegm, qi reversal, heat, retained fluid, essence deficiency, qi descending, qi deficiency, and yang deficiency. Among them, factor 1 accounted for 18.32%, factor 2 accounted for 21.37%, factor 3 accounted for20.43%, factor 4 accounted for 20.61%, and factor 5 accounted for 22.14%. The proportion of zang-fu organs involvement was: 21.37% of the spleen, 17.56% of the kidney, 18.32% of the liver and spleen, and 42.75% of the spleen and kidney. Syndrome elements: yin de?ciency 18.32%, phlegm-dampness 21.37%, qi stagnation 39.69%, qi de?ciency 42.75%, retained ?uid 20.61%, yang de?ciency 60.31%, essence de?ciency 17.56%, qi sinking 17.56%,heat 21.37%, qi reversal 21.37%. Results of cluster analysis: there were 3 cat 展开更多
关键词 Salt-sensitive HYPERTENSION Research of TCM Syndrome Body mass INDEX INSULIN sensitivity INDEX
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Optimizing partitioning strategies for faster inverted index compression
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作者 Xingshen SONG Yuexiang YANG +1 位作者 Yu JIANG Kun JIANG 《中国计算机科学前沿:英文版》 SCIE EI CSCD 2019年第2期343-356,共14页
The inverted index is a key component for search engines to manage billions of documents and quickly respond to users' queries. Whereas substantial effort has been devoted to reducing space occupancy and decoding ... The inverted index is a key component for search engines to manage billions of documents and quickly respond to users' queries. Whereas substantial effort has been devoted to reducing space occupancy and decoding speed, the encoding speed when constructing the index has been overlooked. Partitioning the index aligning to its clustered distribution can effectively minimize the compressed size while accelerating its construction procedure. In this study, we introduce compression speed as one criterion to evaluate compression techniques, and thoroughly analyze the performance of different partitioning strategies. Optimizations are also proposed to enhance state-of-the-art methods with faster compression speed and more flexibility to partition an index. Experiments show that our methods offer a much better compression speed, while retaining an excellent space occupancy and decompression speed, networks. 展开更多
关键词 in verted INDEX INDEX compression OPTIMAL PARTITION APPROXIMATION algorithm
漳州碧湖生态园低碳生态指标体系研究 预览
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作者 林美凤 《建筑与文化》 2019年第6期46-47,共2页
文章研究了国内外生态园区的评价标准和指标体系,并且结合漳州市碧湖生态园的规划目标和发展定位,考虑园区发展的问题及地区特色,构建了适合漳州市碧湖生态园的低碳生态指标体系来指导碧湖生态园区未来的发展和建设。
关键词 绿色 生态 低碳 指标
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Dry/wet snow mapping based on the synergistic use of dual polarimetric SAR and multispectral data
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作者 Divyesh VARADE Onkar DIKSHIT Surendar MANICKAM 《山地科学学报:英文版》 SCIE CSCD 2019年第6期1435-1451,共17页
We propose a multi-sensor multi-spectral and bi-temporal dual-polarimetric Synthetic Aperture Radar(SAR) data integration scheme for dry/wet snow mapping using Sentinel-2 and Sentinel-1 data which are freely available... We propose a multi-sensor multi-spectral and bi-temporal dual-polarimetric Synthetic Aperture Radar(SAR) data integration scheme for dry/wet snow mapping using Sentinel-2 and Sentinel-1 data which are freely available to the research community. The integration is carried out by incorporating the information retrieved from ratio images of the conventional method for wet snow mapping and the multispectral data in two different frameworks. Firstly, a simple differencing scheme is employed for dry/wet snow mapping, where the snow cover area is derived using the Normalized Differenced Snow Index(NDSI). In the second framework, the ratio images are stacked with the multispectral bands and this stack is used for supervised and unsupervised classification using support vector machines for dry/wet snow mapping. We also investigate the potential of a state of the art backscatter model for the identification of dry/wet snow using Sentinel-1 data. The results are validated using a reference map derived from RADARSAT-2 full polarimetric SAR data. A good agreement was observed between the results and the reference data with an overall accuracy greater than 0.78 for the different blending techniques examined. For all the proposed frameworks, the wet snow was better identified. The coefficient of determination between the snow wetness derived from the backscatter model and the reference based on RADARSAT-2 data was observed to be 0.58 with a significantly higher root mean square error of 1.03 % by volume. 展开更多
关键词 SNOW MAPPING Ratio method Normalized Differenced SNOW Index Classification Polarimetric synthetic-aperture RADAR
Secure Inverted Index Based Search over Encrypted Cloud Data with User Access Rights Management
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作者 Fateh Boucenna Omar Nouali +1 位作者 Samir Kechid M.Tahar Kechadi 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期133-154,共22页
Cloud computing is a technology that provides users with a large storage space and an enormous computing power.However,the outsourced data are often sensitive and confidential,and hence must be encrypted before being ... Cloud computing is a technology that provides users with a large storage space and an enormous computing power.However,the outsourced data are often sensitive and confidential,and hence must be encrypted before being outsourced.Consequently,classical search approaches have become obsolete and new approaches that are compatible with encrypted data have become a necessity.For privacy reasons,most of these approaches are based on the vector model which is a time consuming process since the entire index must be loaded and exploited during the search process given that the query vector must be compared with each document vector.To solve this problem,we propose a new method for constructing a secure inverted index using two key techniques,homomorphic encryption and the dummy documents technique.However,1)homomorphic encryption generates very large ciphertexts which are thousands of times larger than their corresponding plaintexts,and 2)the dummy documents technique that enhances the index security produces lots of false positives in the search results.The proposed approach exploits the advantages of these two techniques by proposing two methods called the compressed table of encrypted scores and the double score formula.Moreover,we exploit a second secure inverted index in order to manage the users'access rights to the data.Finally,in order to validate our approach,we performed an experimental study using a data collection of one million documents.The experiments show that our approach is many times faster than any other approach based on the vector model. 展开更多
关键词 searchable ENCRYPTION cloud COMPUTING homomorphic ENCRYPTION attributeqbased ENCRYPTION INVERTED index
Evaluation methods and indexes of morphological characteristics of coarse aggregates for road materials: A comprehensive review
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作者 Saisai Zhang Rui Li Jianzhong Pei 《交通运输工程学报(英文版)》 CSCD 2019年第3期256-272,共17页
The morphological characteristics of coarse aggregates, namely shape profile, angularity and surface texture, have a significant effect on the mechanical properties of asphalt mixtures. The identification methods and ... The morphological characteristics of coarse aggregates, namely shape profile, angularity and surface texture, have a significant effect on the mechanical properties of asphalt mixtures. The identification methods and evaluation indexes of the morphological characteristics are crucial for the coarse aggregates. First, the visual identification technologies, including charged coupled device (CCD) image processing, X-ray tomography imaging and laser scanning technology, are summarized in term of the characteristics, research status and existing problems. Based on the deficiencies of visual identification technologies, it is proposed to improve the three-dimensional reconstruction of aggregate particles by increasing the number of two-dimensional projection directions or scanning sections. Moreover, the evaluation indexes of coarse aggregate morphology were summarized from the three aspects, namely shape profile, angularity and surface texture. It is found that evaluation of the indexes based on two-dimensional profile images or unrelated to pavement performance could not adequately evaluate the morphological characteristics of coarse aggregates. Therefore, the evaluation methods and indexes of coarse aggregate morphological characteristics have been recommended based on the performance of asphalt mixtures in this paper, which is helpful to establish a complete set of an evaluation system for coarse aggregate morphology. 展开更多
关键词 ROAD material Coarse AGGREGATE MORPHOLOGICAL CHARACTERISTIC Identification method Evaluation index
临床医学专业学位硕士研究生导师考核指标的制订与初步应用
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作者 张伟 潘沛 +5 位作者 王欣倍 严晓蕾 黄雪萍 单炯 董艳 刘艳 《中华医学教育探索杂志》 2019年第1期1-4,共4页
住院医师规范化培训的核心内容是临床实践能力培养,同时也是专业学位研究生培养的主要内容。随着专业学位研究生培养与住院医师规范化培训并轨,专业学位研究生导师考核体系应纳入研究生临床技能培训质量指标。通过文献检索、专家咨询等... 住院医师规范化培训的核心内容是临床实践能力培养,同时也是专业学位研究生培养的主要内容。随着专业学位研究生培养与住院医师规范化培训并轨,专业学位研究生导师考核体系应纳入研究生临床技能培训质量指标。通过文献检索、专家咨询等方法合理设置指标结构、考核内容,确定权重,建立临床医学专业学位硕士研究生导师考核细则,引导专业学位研究生导师加强研究生临床技能培养,提高专业学位研究生培养质量。 展开更多
关键词 临床医学 专业学位 研究生 导师 考核 指标
品位和炉渣成分对硅锰冶炼指标的影响 预览
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作者 妥建德 付光军 王先武 《甘肃冶金》 2019年第1期42-44,共3页
根据矿热炉冶炼硅锰合金的生产实践,研究入炉锰品位、炉渣成分变化对产量、回收率、电耗等指标的影响规律,提出硅锰合金冶炼的适宜入炉品位,炉渣碱度、Al2O3控制范围。
关键词 硅锰冶炼 品位 炉渣成分 指标
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