期刊文献+
共找到88篇文章
< 1 2 5 >
每页显示 20 50 100
暗网法律治理问题探究 被引量:8
1
作者 范江波 《信息安全研究》 2018年第7期593-601,共9页
许多人相信Google搜索可以识别互联网上给定主题的大部分信息,整个网络世界是一个巨大的网络世界,超出了Google或任何其他搜索引擎的范围.互联网黑暗网络的规模更是巨大的,截至2015年,由于隐藏在黑暗网络上的服务,暗网经常与深网交替使... 许多人相信Google搜索可以识别互联网上给定主题的大部分信息,整个网络世界是一个巨大的网络世界,超出了Google或任何其他搜索引擎的范围.互联网黑暗网络的规模更是巨大的,截至2015年,由于隐藏在黑暗网络上的服务,暗网经常与深网交替使用;被称为Deep Web的非索引网站的数量估计比索引的可搜索网站的表面网络大400~500倍.Deep Web代表着互联网黑暗的一面.被称为Dark net的Deep Web部分已成为监管的天堂逃避、犯罪和对国家安全的威胁.概要介绍Deep Web是如何访问的,以及为什么应该关心它们.Deep Web的持续增长以及Dark net的加速扩张带来新的政策挑战.对这些挑战的回应可能对公民自由,国家安全和全球经济产生深远的影响. 展开更多
关键词 DeepWeb计算机犯罪 互联网 Tor丝綢之路 国家安全 台理 网络安全
下载PDF
社区抗高血压药物联合应用 被引量:2
2
作者 孙泽艳 《中国社区医师(医学专业)》 2006年第9期9-9,共1页
关键词 抗高血压药物 药物联合应用 心脑血管疾病 社区 最佳治疗效果 高血压病人 危险因素 统一标准 治疗目标 台理用药
下载PDF
学术不端成因分析——基于理性选择制度主义视角
3
作者 童小娟 《黄冈师范学院学报》 2016年第5期120-122,124,共4页
理性选择制度主义认为制度的产生是人们在策略性基础上的利益最大化行为,是个人自我利益理性计算的结果。在学术不端行动者中,学术不端行为人通过对比成本和收益,会理性选择学术不端;部分出版社或学术期刊基于策略性算计,默许学术不端... 理性选择制度主义认为制度的产生是人们在策略性基础上的利益最大化行为,是个人自我利益理性计算的结果。在学术不端行动者中,学术不端行为人通过对比成本和收益,会理性选择学术不端;部分出版社或学术期刊基于策略性算计,默许学术不端的发生;举报人发现了学术不端行为,在衡量成本收益后,一般会理性选择保持沉默;高校监督单位会理性选择沉默或不惩罚,学术不端行为因此产生。提出应建立举报奖励制度,加强学术不端的监督力度,加大惩罚力度来治理学术不端。 展开更多
关键词 学术不端 理性选择制度主义 台理
下载PDF
“河长制”下的水环境修复与治理 被引量:3
4
作者 彭贤则 夏懿 +1 位作者 刘婷 李鹏飞 《湖北师范大学学报(哲学社会科学版)》 2018年第1期81-83,共3页
以水生态修复出发,从水环境治理整体考虑,通过对水生态系统特点,水环境治理中的水质、水安全分析等几个方面提出水环境修复与治理现阶段的问题,从而对水环境系统保护与修复目标,产业发展情况推动经济结构转型升级给出一些建议。
关键词 河长制 水环境 修复 台理
下载PDF
Signal and Data Processing of Television Based on Multistatic Radar Systems 被引量:1
5
作者 李硕 曾涛 龙腾 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期271-275,共5页
A television based multistatic radar system is described. The commercial television transmitter is used as the illuminator in the multistatic radar system. The reflected commercial television signals are measured by ... A television based multistatic radar system is described. The commercial television transmitter is used as the illuminator in the multistatic radar system. The reflected commercial television signals are measured by an array of sensors. A data processing scheme is developed that adapts to the poor signal processing ability. The innovation is focused on the construction of the observation space, which could reduce the non linearity error. The new method leads to better system stability than the traditional one. Monte Carlo simulation is utilized and compared with the traditional method. 展开更多
关键词 multistatic radar television signal signal detection tracking and filter sequential processing
下载PDF
Numerical Study on Tides in the Taiwan Strait and its Adjacent Areas 被引量:3
6
作者 朱佳 胡建宇 +4 位作者 张文舟 曾淦宁 陈德文 陈金泉 商少平 《Marine Science Bulletin》 CAS 2009年第2期23-36,共14页
Diurnal and semi-diurnal tides in the Taiwan Strait and its adjacent areas are calculated by using a two-dimensional finite-difference model. Compared with data of more than 20 observation stations around the Taiwan S... Diurnal and semi-diurnal tides in the Taiwan Strait and its adjacent areas are calculated by using a two-dimensional finite-difference model. Compared with data of more than 20 observation stations around the Taiwan Strait, the model-produced results agree quite well with those of previous researches using observational data from coastal tidal gauge stations. According to the results, the co-tidal and co-range charts are given. Furthermore, the characteristics of 8 major tidal constituents have been uminated respectively. The result shows that: (1) The tide motion can be attributed to the interaction between the degenerative rotary tidal system in the north and the progressive tidal system in the south. (2) The southward and northward tidal waves of semi-diurnal tide converge in the middle of the Taiwan Strait while the diurnal tidal waves propagate southwestward through the Taiwan Strait and the Luzon Strait. (3) The maximum amplitude of semi-diurnal tides exists at the area between the Meizhou Bay and Xinghua Bay, and that of diurnal tides appears in the region to the east of the Leizhou Peninsula, (4) The patterns of co-tidal and co-range charts of N2, K2 and P1, Q1 tidal constituents are similar to those of M2, S2 and K1 O1 tidat constituents, respectively 展开更多
关键词 Taiwan Strait and its adjacent areas tidal characteristics MODEL
下载PDF
Design and Implementation of an Open Network Security Management Platform 被引量:2
7
作者 曹元大 王勇 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期316-320,共5页
In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasib... In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it. 展开更多
关键词 network security management open platform XML RPC SNMP
下载PDF
Research on Software Radio Fuze
8
作者 黄忠华 崔占忠 +1 位作者 林森 栗苹 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期81-85,共5页
The functions and characteristics of software radio are discussed. Using techniques and method of software radio, the concept and advantages of a new kind of radio fuze, software radio fuze, are analysed. Several kind... The functions and characteristics of software radio are discussed. Using techniques and method of software radio, the concept and advantages of a new kind of radio fuze, software radio fuze, are analysed. Several kinds of hardware platform structures of the software radio fuze are studied and the key techniques are analysed. The software radio fuze will become the most promising radio fuze techniques in 21st century. 展开更多
关键词 software radio FUZE hardware platform digital signal processor(DSP)
下载PDF
老年人“四多”饮食最养生
9
作者 王壮凌 《中国保健营养》 2003年第7期33-34,共2页
在影响老年人健康长寿的诸多因素中,合理营养是极其重要的因素之一。专家对老年人的健康饮食提出了“四多”。 多吃鱼 鱼肉鲜嫩,宜于老人食用。美国老人心脏学会2001年推荐成人每周至少吃两次高油脂的鱼。高油脂的鱼包括:鲑鱼、金枪鱼... 在影响老年人健康长寿的诸多因素中,合理营养是极其重要的因素之一。专家对老年人的健康饮食提出了“四多”。 多吃鱼 鱼肉鲜嫩,宜于老人食用。美国老人心脏学会2001年推荐成人每周至少吃两次高油脂的鱼。高油脂的鱼包括:鲑鱼、金枪鱼、鲭鱼(鲐鱼)、美洲鳗鱼、淡水鲟鱼、鲱鱼、沙丁鱼、淡水鳟鱼、鲤鱼、大比目鱼、剑鱼、黑鳕鱼及大黑鱼等。 展开更多
关键词 老年人 饮食结构 养生 台理营养
下载PDF
Soil Physical and Chemical Properties of Five Subtropical Forests in Lingao of Hainan
10
作者 薛杨 宿少锋 +1 位作者 王小燕 林之盼 《Agricultural Science & Technology》 CAS 2017年第8期1459-1464,共6页
With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosi... With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosity was the highest in the Casuarina equisetifolia forest (46.168%), but the lowest in the Encalyptus robusta forest (39.46%). The soil capillary porosity was the highest in the Acacia mangium forest (22.57%), but the lowest in the secondary forest (18.95%). The soil water content was the highest in the C. equisetifolia forest, with a mean value of 27.85%, but the lowest in the secondary forest, with a mean value of 4.34%. The soil pH values were in the range of 4.81-6.59, the soils in the A. mangium forest, C. equisetifolia forest and E. robusta forest were strongly acidic (pH 4.5-5.5), and the soils in the secondary forest and C. nucifera forest were weakly acidic. The soils had organic matter contents in the range of 0.34-28.68 g/kg, and showed an order of A. mangium forest〉C. equisetifolia forest〉E. robusta forest〉secondary forest〉C. nucifera forest, with a decreasing trend with the soil depth increasing. The soil total N contents were in the range of 0.10-1.63 g/kg, the A. mangium forest showed the highest soil total N contents, while the C. nucifera forest exhibited the lowest soil total N contents; the soil total P contents were in the range of 0.21-1.74 g/kg, and the E. robusta forest had the highest soil total P contents; and the soil total K contents were in the range of 0.16-2.15 g/kg, and the A. mangium forest exhibited the highest soil total K contents. The soil available P contents were in the range of 0.98-132.46 mg/kg; and the secondary forests had the highest soil available P contents; and the soil rapidly available K contents were in the range of 3.03-27.35 mg/kg, and the C. nucifera forest exhibited the highest soil rapidly available K contents. The soil ammonium N contents were in the range of 1.38-5.15 mg/kg, and the nitrate N contents were in the range were in the range of 0.56 -3.51 mg/kg. The A. mangium forest showed the highest soil nitrate N contents (with a mean value of 2.29 mg/kg) and ammonium N contents (with a mean value of 3.93 mg/kg). For the same forest type, with the increase of soil depth, the nitrate nitrogen and ammonium nitrogen content also showed a decreasing trend. 展开更多
关键词 Lingao County Coastal platform Different forest types Soil physical and chemical properties COMPARISON
下载PDF
An Application of a Multi-Tier Data Warehouse in Oil and Gas Drilling Information Management 被引量:2
11
作者 张宁生 王志伟 《Petroleum Science》 SCIE CAS CSCD 2004年第4期1-5,共5页
Expenditure on wells constitute a significant part of the operational costs for a petroleum enterprise, where most of the cost results from drilling. This has prompted drilling departments to continuously look for wa... Expenditure on wells constitute a significant part of the operational costs for a petroleum enterprise, where most of the cost results from drilling. This has prompted drilling departments to continuously look for ways to reduce their drilling costs and be as efficient as possible. A system called the Drilling Comprehensive Information Management and Application System (DCIMAS) is developed and presented here, with an aim at collecting, storing and making full use of the valuable well data and information relating to all drilling activities and operations. The DCIMAS comprises three main parts, including a data collection and transmission system, a data warehouse (DW) management system, and an integrated platform of core applications. With the support of the application platform, the DW management system is introduced, whereby the operation data are captured at well sites and transmitted electronically to a data warehouse via transmission equipment and ETL (extract, transformation and load) tools. With the high quality of the data guaranteed, our central task is to make the best use of the operation data and information for drilling analysis and to provide further information to guide later production stages. Applications have been developed and integrated on a uniform platform to interface directly with different layers of the multi-tier DW. Now, engineers in every department spend less time on data handling and more time on applying technology in their real work with the system. 展开更多
关键词 drilling information management multi-tier data warehouse information processing application system
下载PDF
Wave-current interaction during Typhoon Nuri(2008)and Hagupit(2008):an application of the coupled ocean-wave modeling system in the northern South China Sea 被引量:3
12
作者 ZHANG Chen HOU Yijun LI Jian 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期663-675,共13页
The northern South China Sea(SCS) is frequently affected by typhoons. During severe storm events, wave-current interactions produce storm surges causing enormous damage in the path of the typhoon. To evaluate the infl... The northern South China Sea(SCS) is frequently affected by typhoons. During severe storm events, wave-current interactions produce storm surges causing enormous damage in the path of the typhoon. To evaluate the influence of wave-current interactions on storm surge, we used a coupled ocean-atmospherewave-sediment transport(COAWST) modeling system with radiation-stress and vortex-force formulations to simulate two typically intense tropical storms that invaded the SCS, namely Typhoons Nuri(2008) and Hagupit(2008), and compared results with observations from the Hong Kong Observatory. Both radiationstress and vortex-force formulations significantly improved the accuracy of the simulation. Depending on which typhoon and the topography encountered, the influence of surface waves on the oceanic circulation showed different characteristics, including the differences of range and intensity of storm surge between vortex-force and radiation-stress experiments. During typhoon landing, strong sea-surface elevation in concert with wave set-up/set-down caused the adjustment of the momentum balance. In the direction perpendicular to the current, but especially in the cross-shore direction, the pressure gradient and wave effects on the current dominated the momentum balance. 展开更多
关键词 northern South China Sea wave-current interactions storm surge coupled ocean-atmosphere-wave-sediment transport(COAWST) modeling system
下载PDF
Geomorphic Characteristics of Hillslope and Channelized Debris Flows: A Case Study in the Shitou Area of Central Taiwan 被引量:3
13
作者 Jinn-Chyi CHEN Ching-Weei LIN Lung-Chang WANG 《Journal of Mountain Science》 SCIE CSCD 2009年第3期266-273,共8页
The data on the hillslope and channelized debris flows in the Shitou area of central Taiwan occurred during Typhoons Toraji and Nali in 2001 were applied in this paper. The geomorphic parameters, including the flow le... The data on the hillslope and channelized debris flows in the Shitou area of central Taiwan occurred during Typhoons Toraji and Nali in 2001 were applied in this paper. The geomorphic parameters, including the flow length, gully gradient, drainage area and form factor of the debris flows were determined by spatial analysis using a Geographic Information System (GIS) based on the data derived from field investigation, aerial photographs, and topographical maps. According to such determined geomorphic parameters, the threshold conditions and empirical equations, such as the relationship between the gully gradient and drainage area and that between gully length and drainage area and topographic parameter, are presented and used to distinguish the geomorphic characteristics between the channelized and hillslope debris flows. 展开更多
关键词 Hillslope debris flow Channelized debris flow Empirical equation Topographic parameter Central Taiwan China
下载PDF
GIS applications in typhoon simulation and Hazard assessment 被引量:5
14
作者 常亮 段忠东 欧进萍 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第4期383-387,共5页
GIS technology provides a powenful tool for disaster hazard assessment and mitigation. A GIS based system is developed for typhoon data management and analysis, typhoon simulation and hazard assessment for southeast c... GIS technology provides a powenful tool for disaster hazard assessment and mitigation. A GIS based system is developed for typhoon data management and analysis, typhoon simulation and hazard assessment for southeast coast of China in this paper. A typhoon database by Microsoft Access is designed. Data manipulation and analysis, typhoon simulation and hazard assessment, and visualization of results are implemented on GIS platform. This GIS-based typhoon database and analysis system greatly facilitates typhoon hazard assessment. 展开更多
关键词 GIS TYPHOON hazard analysis disaster mitigation
下载PDF
AN SENSITIVITY SIMULATION ABOUT CLOUD MICROPHYSICAL PROCESSES OF TYPHOON CHANCHU 被引量:2
15
作者 林文实 吴剑斌 +3 位作者 李江南 梁旭东 方杏芹 徐穗珊 《Journal of Tropical Meteorology》 SCIE 2010年第4期390-401,共12页
With the Reisner-2 bulk microphysical parameterization of the fifth-generation Pennsylvania State University-U.S. National Center for Atmospheric Research (PSU--NCAR) Mesoscale Model (MM5), this paper investigates... With the Reisner-2 bulk microphysical parameterization of the fifth-generation Pennsylvania State University-U.S. National Center for Atmospheric Research (PSU--NCAR) Mesoscale Model (MM5), this paper investigates the microphysical sensitivities of Typhoon Chanchu. Four different microphysical sensitivity experiments were designed with an objective to evaluate their respective impacts in modulating intensity forecasts and microphysics budgets of the typhoon. The set of sensitivity experiments were conducted that comprised (a) a control experiment (CTL), (b) NEVPRW from which evaporation of rain water was suppressed, (c) NGP from which graupel was taken, and (d) NMLT from which melting of snow and graupel was removed. We studied the impacts of different cloud microphysical processes on the track, intensity and precipitation of the typhoon, as well as the kinematics, thermodynamics and vertical structural characteristics of hydrometeors in the inner core of the typhoon. Additionally, the budgets of the cloud microphysical processes in the fine domain were calculated to quantify the importance of each microphysical process for every sensitivity experiment. The primary results are as follows: (1) It is found that varying cloud microphysics parameters produce little sensitivity in typhoon track experiments. (2) The experiment of NGP produces the weakest storm, while the experiment of NMLT produces the strongest storm, and the experiment of NEVPRW also produces stronger storms than CTL. (3) Varying parameters of cloud rnicrophysics have obvious impacts on the precipitation, kinematics, and thermodynamics of the typhoon and the vertical structural characteristics of hydrometeors in the typhoon's inner core. (4) Most budgets of cloud microphysics in NMLT are larger than in CTL, while they are 20%-60% smaller in NEVPRW than in CTL. 展开更多
关键词 Typhoon Chanchu cloud microphysics SIMULATION
下载PDF
THE IMPACT OF CUMULUS PARAMETERIZATIONS AND MICROPHYSICS SCHEMES UNDER DIFFERENT COMBINATIONS ON TYPHOON TRACK PREDICTION 被引量:1
16
作者 河惠卿 王振会 +2 位作者 金正润 牛生杰 徐爱淑 《Journal of Tropical Meteorology》 SCIE 2011年第2期113-119,共7页
This study examines the effects of cumulus parameterizations and microphysics schemes on the track forecast of typhoon Nabi using the Weather Research Forecast model. The study found that the effects of cumulus parame... This study examines the effects of cumulus parameterizations and microphysics schemes on the track forecast of typhoon Nabi using the Weather Research Forecast model. The study found that the effects of cumulus parameterizations on typhoon track forecast were comparatively strong and the typhoon track forecast of Kain-Fritsch (KF) was superior to that of Betts-Miller (BM). When KF was selected, the simulated results would be improved if microphysics schemes were selected than otherwise. The results from Ferrier, WSM6, and Lin were very close to those in the best track. KF performed well with the simulations of the western extension and eastern contraction changes of a North Pacific high as well as the distribution and strength of the typhoon wind field. 展开更多
关键词 cumulus parameterizations microphysics schemes typhoon track prediction
下载PDF
Epidemiological and histopathological study of relevance of Guizhou Maotai liquor and liver diseases 被引量:15
17
作者 WuJ ChenML 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期571-574,共4页
AIM: To explore the relevance of Maotai liquor and liver diseases. METHODS: Epidemiological study was conducted on groups of subjects, each consisting of 3 subjects from the Maotai liquor group consisting of 99 indivi... AIM: To explore the relevance of Maotai liquor and liver diseases. METHODS: Epidemiological study was conducted on groups of subjects, each consisting of 3 subjects from the Maotai liquor group consisting of 99 individuals and one from the non-alcoholic control group consisting of 33 individuals. Liver biopsy was performed on 23 volunteers from Guizhou Maotai Distillery who had a constant and long history of drinking Maotai liquor. Experimental histopathological study was conducted as follows: sixty male Wistar rats were divided into 3 groups randomly and fed with Maotai liquor, ordinary white wine, and physiological saline respectively for a period of 8 and 12 weeks. The rats were sacrificed in batches, then serum ALT, AST, TBil, and AKP were measured. Rat livers were harvested to measure the liver indexes, GSH, and MDA. Histopathological examinations were also performed. Another eighty mice were randomly divided into 4 groups and fed with Maotai (at different dosages of 10 ml.kg(-1) and 20 ml.kg(-1)), ethanol, and physiological saline. The animals were sacrificed after 4 weeks and serum ALT was determined. Then the livers were harvested and liver indexes and MDA were measured. RESULTS: The incidence rate of hepatic symptoms, splenomegaly, liver function impairment, reversal of Albumin/Globulin and increased diameter of portal veins in the Maotai liquor group were 1.0% 1/99 , 1.0% 1/99 , 1.0% 1/99 , 1.0% 1/99 , 0 0/99 and 0 0/99 , 0 0/99 ,0 0/99 , 0 0/99 , 0 0/99 , respectively. There was no significant difference between the Maotai group and the non-alcoholic control group P】0.05 . Various degree of fatty infiltration of hepatocytes was found in the 23 volunteers receiving liver biopsy, but there was no obvious hepatic fibrosis or cirrhosis. A comparison was made between the Maotai liquor group and the ordinary white wine group. It was found that hepatic MDA in rats and mice were 0.33+/-0.10 and 0.49+/-0.23 respectively in Maotai group and 0.61+/-0.22 and 0.66+/-0.32 in the ordinary white wine group; MDA had an obvious decrease in the Maotai liquor group (P【0.05); hepatic GSH were 0.12 mg.g(-1)+/-0.06 mg.g(-1) in rats of the Maotai liquor group and (0.08+/-0.02)mg.g(-1) in white wine group, it was obviously increased in the Maotai liquor group (P【0.05). After the 20 rats had been fed with ordinary white wine for 8 weeks consecutively, disarranged hepatocyte cords, fatty infiltration of hepatocytes, and fibrous septa of varying widths due to hepatic connective tissues proliferation were observed; after 12 weeks, the fibrous tissue proliferation continued and early cirrhosis appeared. Compared with the ordinary white wine group, fatty infiltration was observed in the 8-week and 12-week groups, but no necrosis or fibrosis or cirrhosis was found in the Maotai liquor group (P【0.05). CONCLUSION: Maotai liquor may cause fatty liver but not hepatic fibrosis or cirrhosis, and it can strengthen lipid peroxidation in the liver. 展开更多
关键词 Adult Alcoholic Beverages Animals China Fatty Liver Alcoholic Female Humans Liver Cirrhosis Alcoholic Liver Diseases Alcoholic Male Mice Middle Aged RATS Rats Wistar Research Support Non-U.S. Gov't Wine
下载PDF
Challenges and Solutions of Information Security Issues in the Age of Big Data 被引量:6
18
作者 YANG Mengke ZHOU Xiaoguang +1 位作者 ZENG Jianqiu XU Jianjian 《China Communications》 SCIE CSCD 2016年第3期193-202,共10页
Big data has been taken as a Chinese national strategy in order to satisfy the developments of the social and economic requirements and the development of new information technology. The prosperity of big data brings ... Big data has been taken as a Chinese national strategy in order to satisfy the developments of the social and economic requirements and the development of new information technology. The prosperity of big data brings not only convenience to people's daily life and more opportunities to enterprises, but more challenges with information security as well. This paper has a research on new types and features of information security issues in the age of big data, and puts forward the solutions for the above issues: build up the big data security management platform, set up the establishment of information security system and implement relevant laws and regulations. 展开更多
关键词 information security big data data privacy information technology
下载PDF
A SUPER-RESOLUTION APPROACH TO SAR PROCESSING
19
作者 邱晓晖 朱兆达 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第2期131-135,共5页
Compared with other methods, the chirp scaling (CS) algorithm is a novel one for compensating the range migration without any interpolation in SAR imaging. However, its resolution ability can't exceed that of Four... Compared with other methods, the chirp scaling (CS) algorithm is a novel one for compensating the range migration without any interpolation in SAR imaging. However, its resolution ability can't exceed that of Fourier transformation. To realize the super-resolution ability in the azimuth direction a chirp scaling Burg (CSB) algorithm is proposed in this paper, which can still reserve the advantage of avoiding any interpolation in the process of the two-dimensional space-variant correlation in the CS algorithm. 展开更多
关键词 synthetic aperture radar signal processing super resolution
下载PDF
Landform Planation Index Extracted from DEMs: A Case Study in Ordos Platform of China 被引量:3
20
作者 QIAN Yeqing XIONG Liyang +1 位作者 LI Jilong TANG Guoan 《Chinese Geographical Science》 SCIE CSCD 2016年第3期314-324,共11页
Planation surface, a surface that is almost flat, is a kind of low-relief landforms. Planation surface is the consequence of the denudation and planation processes under a tectonic stable condition. The quantitative e... Planation surface, a surface that is almost flat, is a kind of low-relief landforms. Planation surface is the consequence of the denudation and planation processes under a tectonic stable condition. The quantitative expression of the characteristics of planation surface plays a key role in reconstructing and describing the evolutionary process of landforms. In this study, Landform Planation Index(LPI), a new terrain derivative, was proposed to quantify the characteristics of planation surface. The LPIs were calculated based on the summit surfaces formed according to the clustering results of peaks. Ten typical areas in the Ordos Platform located in the central part of the Loess Plateau of China are chosen as the test areas for investigating their planation characteristics with the LPI. The experimental results indicate that the LPI can be effectively used to quantify the characteristics of planation surfaces. In addition, the LPI can be further used to depict the patterns of spatial differentiation in the Ordos Platform. Although the present Ordos Platform area is full of the high-density gullies, its planation characteristics is found to be well preserved. Furthermore, the characteristics of the planation surfaces can also reflect the original morphology of the Ordos Platform before the loess dusts deposition process evolved in this area. The statistical results of the LPI show that there is a gradually increasing tendency along with the increasing of slope gradient of summit surface. It indicates that the characteristics of planation surfaces vary among test areas with different landforms. These findings help to deepen the understanding of planation characteristics of the loess landform and its underlying paleotopography. Results of this study can be also served as an important theoretical reference value for revealing the evolutionary process of loess landform. 展开更多
关键词 Landform Planation Index(LPI) peak summit surface Digital Elevation Model(DEM) Ordos Platform China
下载PDF
上一页 1 2 5 下一页 到第
使用帮助 返回顶部