期刊文献+
共找到2,954篇文章
< 1 2 148 >
每页显示 20 50 100
The Genus Rhithrogena Eaton (Ephemeroptera: Heptageniidae) from Chinese Mainland, with Description of a New Species 被引量:1
1
作者 周长发 郑乐怡 《Entomotaxonomia》 CSCD 北大核心 2004年第2期81-85,共5页
In present paper the genus Rhithrogena Eaton from Chinese mainland, including a new species to science (Rhithrogena lutea, sp. nov.), 2 new record species from China (R. bajkovae Sowa, R. lepnevae Brodsky) and 3 known... In present paper the genus Rhithrogena Eaton from Chinese mainland, including a new species to science (Rhithrogena lutea, sp. nov.), 2 new record species from China (R. bajkovae Sowa, R. lepnevae Brodsky) and 3 known species [R. wuyinensis (Gui et al.) (comb. nov.), R. trispina Zhou et Zheng, R. orientalis You (= R. sangangensis You, new synonym)] are revised besed on the imaginal specimens. A key to 7 species imagos is provided. All materials in this study are deposited in Nanjing Normal University. 展开更多
关键词 EPHEMEROPTERA HEPTAGENIIDAE Rhithrogena Chinese mainland +
在线阅读 下载PDF
A Preliminary Study on the Genus Caenis (Ephemeroptera: Caenidae) from Chinese Mainland, with Description of a New Species
2
作者 周长发 郑乐怡 《Entomotaxonomia》 CSCD 北大核心 2004年第1期1-7,共7页
Five species of the genus Caenis from Chinese mainland are reviewed. Among them, C. parviforcipis (Zhou et al.) (nov. comb.) is transferred from the genus Brachycercus The larvae of the C. sinensis Gui et al. are desc... Five species of the genus Caenis from Chinese mainland are reviewed. Among them, C. parviforcipis (Zhou et al.) (nov. comb.) is transferred from the genus Brachycercus The larvae of the C. sinensis Gui et al. are described for the first time. The previously reported C. nigroforceps Zhou et al. is recognized as a new synonym of the Caenis rivulorum Eaton, and the report of C. nigropunctata Klapálek from China is confirmed. Both imagos and larvae of a new species C. melanoleuca, sp. nov. are described and illustrated in detail. 展开更多
关键词 EPHEMEROPTERA Caenidae Caenis REVISION Chinese mainland
在线阅读 下载PDF
Surveillance of Hand,Foot,and Mouth Disease in China's Mainland (2008-2009) 被引量:77
3
作者 ZHU Qi HAO YuanTao +2 位作者 MA JiaQi YU ShiCheng WANG Yu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第4期349-356,共8页
Objective Since HFMD was designated as a class C communicable disease in May 2008,18 months surveillance data have been accumulated to December 2009.This article was to describe the distribution of HFMD for age,sex,ar... Objective Since HFMD was designated as a class C communicable disease in May 2008,18 months surveillance data have been accumulated to December 2009.This article was to describe the distribution of HFMD for age,sex,area,and time between 2008 and 2009,to reveal the characteristics of the epidemic.Methods We analyzed weekly reported cases of HFMD from May 2008 to December 2009,and presented data on the distribution of age,sex,area and time.A discrete Poisson model was used to detect spatial-temporal clusters of HFMD.Results More than 1 065 000 cases of HFMD were reported in China's Mainland from May 2008 to December 2009 (total incidence:12.47 per 10 000).Male incidence was higher than female for all ages and 91.9% of patients were 5 years old.The incidence was highest in Beijing,Shanghai,Zhejiang and Hainan.The highest peak of HFMD cases was in April and the number of cases remained high from April to August.The spatial-temporal distribution detected four clusters.Conclusion Children 5 years old were susceptible to HFMD and we should be aware of their vulnerability.The incidence was higher in urban than rural areas,and an annual pandemic usually starts in April. 展开更多
关键词 HAND FOOT and mouth disease China's mainland SURVEILLANCE Epidemiologic features
在线阅读 下载PDF
Recurrence behaviors of segment-rupturing earthquakes on active faults of the Chinese mainland 被引量:8
4
作者 闻学泽 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第4期457-465,共9页
To investigate the recurrence behaviors of segment-rupturing eathquakes on active faults of the Chinese mainland, thispaper analyzes quantitatively earthquake history of 19 fault segments based on earthquake dam of mu... To investigate the recurrence behaviors of segment-rupturing eathquakes on active faults of the Chinese mainland, thispaper analyzes quantitatively earthquake history of 19 fault segments based on earthquake dam of multi-cyclerecurrences. The result shows that, for these fault segments, eanhquake recurring at previous locations is mainlycharacterized by both quasi-periodic (in a ratio of about) and time-predictable (in a ratio of about) behaviors.For the first behavior. intrinsic uncertainty of recurrence interval accounts for 0. 15-0.40 of the average interval, andmagnitudes of event vary from cycle to cycle within the range of the mean magnitUde t0.5. For the second behavior,intrinsic uncertainty of recurrence interval ranges mostly from 0. 19 to 0.40 of the average interval, and for successivetwo cycles the maximum change of event magnitudes is as much as 1.7 magnitude-units. In addition, for a few casesthe first behavior coexists along with either the second or the slip-predictable behaviors. 展开更多
关键词 active faults segment-rupturing earthquake RECURRENCE behavior Chinese mainland
在线阅读 下载PDF
Spatiotemporal dynamics of electric power consumption in Chinese Mainland from 1995 to 2008 modeled using DMSP/OLS stable nighttime lights data 被引量:28
5
作者 HE Chunyang MA Qun +2 位作者 LI Tong YANG Yang LIU Zhifeng 《Journal of Geographical Sciences》 SCIE CSCD 2012年第1期125-136,共12页
Electric power consumption(EPC)is one of the basic indices for evaluating electric power use.Obtaining timely and accurate data on the spatiotemporal dynamics of EPC is crucial for understanding and practical deployme... Electric power consumption(EPC)is one of the basic indices for evaluating electric power use.Obtaining timely and accurate data on the spatiotemporal dynamics of EPC is crucial for understanding and practical deployment of electric power resources.In this study,an EPC model was developed using stable nighttime lights time-series data from the Defense Meteorological Satellite Program Operational Linescan System(DMSP/OLS).The model was used to reconstruct the spatial patterns of EPC in Chinese Mainland at the county level from 1995 to 2008.In addition,the spatiotemporal dynamics of EPC were analyzed,and the fol-lowing conclusions were drawn.(1)The EPC model reliably represented the spatiotemporal dynamics of EPC in Chinese Mainland with approximately 70%accuracy.(2)The EPC in most regions of Chinese Mainland was at low to moderate levels,with marked temporal and spatial variations;of high-level EPC,58.26%was concentrated in eastern China.Six urban agglomerations(Beijing-Tianjin-Tangshan region,Shanghai-Nanjing-Hangzhou region,Pearl River Delta,Shandong Peninsula,middle-south of Liaoning Province,and Sichuan Basin)accounted for 10.69%of the total area of Chinese Mainland but consumed 39.23%of the electricity.(3)The EPC of most regions in Chinese Mainland increased from 1995 to 2008,and 64%of the mainland area showed a significant increase in EPC.Moderate increases in EPC were found in 61.62%of eastern China and 80.65%of central China from 1995 to 2008,whereas 75.69%of western China showed no significant increase in EPC.Meanwhile,77.27%,89.35%,and 66.72%of the Shanghai-Nanjing-Hangzhou region,Pearl River Delta,and Shandong Peninsula,respectively,showed high-speed increases in EPC.Moderate increases in EPC occurred in 71.12%and 72.13%of the Beijing-Tianjin-Tangshan region and middle-south of Liaoning Province,respectively,while no significant increase occurred in 56.34%of the Sichuan Basin. 展开更多
关键词 DMSP/OLS electric power consumption spatiotemporal dynamics Chinese mainland
原文传递
Distribution of empirical recurrence intervals for segment-rupturing earthquakes onactive faults of the Chinese mainland 被引量:6
6
作者 闻学泽 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第6期667-675,共9页
For the two main recurrence behaviors of segment-rupturing earthquakes on active faults of the Chinese mainland,this paper establishes corresponding empirical distributions forearthquake recurrence interval. The resul... For the two main recurrence behaviors of segment-rupturing earthquakes on active faults of the Chinese mainland,this paper establishes corresponding empirical distributions forearthquake recurrence interval. The results show that, for the time-predictable recurrence, the normalized recurrence interval, T/Tt, obeys very well the lognormal distributions: LN (μ1=0.00, σ21 =0. 152), where, T is an observed recurrence interval, and Tt is the average recurrence interval that is correlative with the size of the preceding event. For the quasi-periodic recurrence, the normalized recurrence interval, T/T, follows the lognormal distribution : LN(μq=0.00, σ2q=0.242), where, T is the median of recurrence intervals for various cycles. A statistical test suggests that, there is no significant difference between the latter distribution, built by this paper, and the recurrence interval distribution for the characteristic earthquakes of the Circum-Pacific Plate boundaries (NB model). Accordingly, this paper combines these two distributions into one and obtains a more stable lognormal distribution :LN (μ = 0.00, σ2 = 0.222), for the quasi-periodic recurrence interval. 展开更多
关键词 segment-rupturing earthquake time-predictable RECURRENCE QUASI-PERIODIC RECURRENCE probability DISTRIBUTION Chinese mainland
在线阅读 下载PDF
Hyperthermic intraperitoneal chemotherapy for gastric and colorectal cancer in China's Mainland 被引量:18
7
作者 Tao Suo Haile Mahteme Xin-Yu Qin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第8期1071-1075,共5页
AIM:To investigate the current status of peritoneal carcinomatosis(PC) management,as well as the usage of cytoreductive surgery(CRS) and hyperthermic intraperitoneal chemotherapy(HIPEC) in China's Mainland.METHODS... AIM:To investigate the current status of peritoneal carcinomatosis(PC) management,as well as the usage of cytoreductive surgery(CRS) and hyperthermic intraperitoneal chemotherapy(HIPEC) in China's Mainland.METHODS:A potentially curative therapeutic strategy for selecting patients with PC,known as "Techniques",consists of CRS in combination with HIPEC.A systemic search of published works and clinical trials was performed.Additional papers were retrieved by crosschecking references and obtaining information from Chinese oncologists and relevant conferences.One hundred and one papers and one registered clinical trial on HIPEC were included.RESULTS:A literature review identified 86 hospitals in 25 out of all 31 areas of China's Mainland that perform HIPEC.The earliest report included in our survey was published in 1993.Different approaches to HIPEC have been utilized,i.e.palliative,prophylactic,and possiblycurative treatment.Only one center has consistently performed HIPEC according to the "Sugarbaker Protocol",which involves evaluating the extent of PC with peritoneal cancer index and the results of CRS with the completeness of cytoreduction.Positive preliminary results were reported:7 of 21 patients with PC survived,free of tumors,during an 8-43-mo follow-up period.Hyperthermic strategies that include HIPEC have been practiced for a long time in China's Mainland,whereas the "Sugarbaker Protocol/Techniques" has been only rarely implemented in China.The Peritoneal Surface Oncology Group International hosts a biannual workshop with the intent to train more specialists in this field and provide support for the construction of quality treatment centers,especially in developing countries like China,whose population is huge and has a dramatically increased incidence of cancer.CONCLUSION:To popularize Sugarbaker Protocol/Techniques in China's Mainland in PC management arising from gastric cancer or colorectal cancer will be the responsibility of the upcoming Chinese Peritoneal Surface Oncology Group. 展开更多
关键词 Peritoneal carcinomatosis HYPERTHERMIA Prophylactic strategy Sugarbaker Protocol/techniques China's mainland
在线阅读 下载PDF
Molecular Epidemiology of Enteroviruses Associated with Hand, Foot, and Mouth Disease in the Mainland of China 被引量:24
8
作者 ZHANG Yong XU Wen Bo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第11期875-876,共2页
Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontan... Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontaneously, include mucocutaneous papulovesicular lesions on the hands, feet, mouth, and buttocks. In rare cases, however, the patients may also develop neurological complications such as neurogenic pulmonary edema, 展开更多
关键词 HFMD CVA FOOT Molecular Epidemiology of Enteroviruses Associated with Hand and Mouth Disease in the mainland of China
暂未订购
Recent gravity changes in China Mainland 被引量:8
9
作者 Li Hui Shen Chongyang +3 位作者 Sun Shaoan Wang Xiaoquan Xiang Aimin Liu Shaoming 《Geodesy and Geodynamics》 2011年第1期1-12,共12页
Based on results of the mobile gravity measurements of the Crustal Movement Observation Network of China and Digital Earthquake Observation Network of China, this paper shows the pattern of temporal gravity changes in... Based on results of the mobile gravity measurements of the Crustal Movement Observation Network of China and Digital Earthquake Observation Network of China, this paper shows the pattern of temporal gravity changes in China mainland on a time scale of 2 - 3 years since 1998, and gives an analysis of the patterns. The result shows that the temporal gravity changes basically reflect the current mass movement and occurrence of strong earthquakes. 展开更多
关键词 China mainland gravimetric network GRAVIMETRY gravity change crust movement
原文传递
Surface wave tomography of the crust and upper mantle of Chinese mainland and its neighboring region 被引量:5
10
作者 何正勤 丁志峰 +2 位作者 叶太兰 孙为国 张乃铃 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第6期634-641,共8页
The three dimensional S wave velocity structure of the crust and upper mantle of Chinese mainland and its neighboring region is obtained by genetic algorithm of surface wave tomography, with smoothness constraint, bas... The three dimensional S wave velocity structure of the crust and upper mantle of Chinese mainland and its neighboring region is obtained by genetic algorithm of surface wave tomography, with smoothness constraint, based on 25 wave group velocities for the periods from 10 s to 92 s, measured from long period Rayleigh waves recorded by 11 stations of CDSN and 12 digital seismometers surrounding China. The S wave velocity image is shown on two latitudinal sections along 30°N and 38°N, two longitudinal sections along 90°E and 120°E, and four horizontal slices at the different depths. 展开更多
关键词 Rayleigh wave seismic tomography the Chinese mainland crust and upper mantle velocity structure
在线阅读 下载PDF
Boundary conditions of the dynamicnumerical model for the Chinese mainland lithosphere 被引量:4
11
作者 张东宁 许忠淮 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期148-154,共7页
The numerical dynamic model of Chinese mainland lithosphere's stress and strain field was constructed withelasto-viscous creep constitive relation. The most recent data of the stress field of Chinese mainland and ... The numerical dynamic model of Chinese mainland lithosphere's stress and strain field was constructed withelasto-viscous creep constitive relation. The most recent data of the stress field of Chinese mainland and thehorizontal movement velocity of the crust blocks were used as constraint conditions. The values of the boundalsforce were computed by trial-and-error method. The effect of the Qinghai-Xizang Plateau's excess potential energyto the movement of Chinese mainland was studied also in this model. The results of the numerical computing showthat, recent rapid raising of the Qinghai-Xizang Plateau and the generation of normal faults in the southem part ofthe plateau resulted from the convergence of Indian Plate to the Eurasian Plate, and also from the rapid convectivethinning of the lower lithosphere. Horizontal extension of the Qinghai-Xizang Plateau is the main dynamic factorto torm the present tectonic framework of the Chinese mainland. The compressive loads on the eastern boundaryof the model were mainly applied by the subduction of the Pacific Plate. The compression from the PhilippinePlate maybe slight. 展开更多
关键词 Chinese mainland stress field movement rate boundary conditions finite element
在线阅读 下载PDF
Development of the Transitional Care Model for nursing care in China's Mainland:A literature review 被引量:11
12
作者 Zeng-Jie Ye Mei-Ling Liu +4 位作者 Rui-Qing Cai Mei-Xia Zhong Hui Huang Mu-Zhi Liang Xiao-Ming Quan 《International Journal of Nursing Sciences》 2016年第1期113-130,共18页
Background:The Transitional Care Model(TCM)for nursing care has yet to be implemented in China despite its success in Western countries.However,rapid social changes have demanded an upgrade in the quality of nursing c... Background:The Transitional Care Model(TCM)for nursing care has yet to be implemented in China despite its success in Western countries.However,rapid social changes have demanded an upgrade in the quality of nursing care;in 2010,the Chinese government has acknowledged the need to implement the TCM in China.Objective:This study has the following objectives:(1)perform a thorough review of the literature regarding the development and implementation of the TCM in China's Mainland within the past 5 years;(2)provide a comprehensive discussion of the current status,problems,and strategies related to the implementation of the TCM in China's Mainland;and(3)suggest strategies pertaining to the future of the TCM in China.Design:The current pertinent literature is systematically reviewed.Data sources:Systematic and manual searches in computerized databases for relevant studies regarding the TCM led to the inclusion of 26 papers in this review.Review methods:Abstracts that satisfied the inclusion criteria were reviewed independently by the two authors of this manuscript,and discrepancies were resolved through discussion.The same reviewers independently assessed the paper in its entirety for selected abstracts.Results:The present English literature reviewrevealed a paucity of updated information about the development and implementation of the TCM in China's Mainland.Nevertheless,the dramatic growth of the TCM in the past 5 years has had a vital impact within the society and in nursing development.This review also revealed numerous issues regarding the focus of the TCM.Overall implications for practiceandrecommendations for future researchare discussed.Conclusion:Despite the potential of this nursing model to have a successful and beneficial impact in China's Mainland,it remains an under-researched topic.Further research on education and training as well as premium policies for nurses under the TCM are needed. 展开更多
关键词 Transitional Care Model Continued nursing Continuity of care Health care needs DEVELOPMENT mainland China
暂未订购
ANALYSIS ON THE CHARACTERISTICS OF TROPICAL CYCLONES MAKING LANDFALL ON DIFFERENT REGIONS OF CHINESE MAINLAND 被引量:3
13
作者 尹宜舟 朱志存 +1 位作者 叶殿秀 黄强 《Journal of Tropical Meteorology》 SCIE 2013年第3期276-283,共8页
The locations(longitudes and latitudes)of the tropical cyclones(TCs)making landfall on the Chinese mainland from 1949 to 2008 are investigated in detail by using ArcGis and FORTRAN routine.The southeast coastline[110 ... The locations(longitudes and latitudes)of the tropical cyclones(TCs)making landfall on the Chinese mainland from 1949 to 2008 are investigated in detail by using ArcGis and FORTRAN routine.The southeast coastline[110 to 122°E)with most landfall TCs was selected as the key region,which was divided into 12 subsections with 1°intervals of longitude.The study period was from July to September in each year.The result showed that the average sustaining time of TCs making landfall on the subsections east of 118°E is longer than those west of 118°E.Before landfall,the averaged TC intensity in the subsections east of118°E is stronger than that west of it.After landfall,however,the difference between the west and east is not significant.The index of destructive potential for the period before/after landfall was defined as TDP1/TDP2.The maximum of TDP1/TDP2 occurred in the subsection of[119,120°E)/[110,111°E).The ENSO impact on the frequency and average location of landfall TC over the whole region at 110 to 122°E is not obvious,but the effect varies with specific subsections.There is little differences of averaged TDP1 in the subsections between different phases of ENSO events,but the averaged TDP2 is larger in the warm events than that in the cold events.The rainstorm days of each station caused by TCs in different subsections were counted respectively.The results suggested that the rainstorm days of the subsections east of 118°E are much more than those west of 118°E.The larger values are primarily distributed at the subsections of[119,120°E)and[110,111°E). 展开更多
关键词 Chinese mainland LANDFALL tropical cyclone CHARACTERISTICS ANALYSIS destructive potential RAINSTORM frequency
在线阅读 下载PDF
Crustal deformation on the Chinese mainland during 1998—2004 based on GPS data 被引量:75
14
作者 Zhao Bin Huang Yong +3 位作者 Zhang Caihong Wang Wei Tan Kai Du Rinlin 《Geodesy and Geodynamics》 2015年第1期7-15,共9页
This study focuses on resolving moderate amounts of crustal motion at the continental scale based on a large volume of global positioning system(GPS) data during 1998e2014. A state-of-the-art GPS processing strategy... This study focuses on resolving moderate amounts of crustal motion at the continental scale based on a large volume of global positioning system(GPS) data during 1998e2014. A state-of-the-art GPS processing strategy was used to resolve position time series and velocities from carrier beat phases for all available data. Position time series were closely analyzed to estimate linear constant, coseismic displacements, postseismic motions, and other parameters. We present coseismic offsets inferred from the GPS data for the 2010 Yushu and 2014 Yutian earthquakes, and also illustrate transient postseismic motions following the 2001 Kokoxili, 2008 Wenchuan, and 2011 Tohoku-Oki earthquakes. Since not all GPS position time series dominated by postseismic motions can be modeled and corrected reasonably, we present contemporary horizontal velocities from 2009 to 2014 for campaign stations and from 1998 to 2014 for continuous stations, irrespective of postseismic deformations. Our study concludes that we need to accumulate observations over a greater duration and apply accurate postseismic modeling to correct for transient displacement in order to resolve reasonable interseismic velocity. 展开更多
关键词 Velocity field Coseismic deformation Postseismic deformation Error analysis Chinese mainland
原文传递
Crustal block rotations in Chinese mainland revealed by GPS measurements 被引量:3
15
作者 Wei Wang Shaomin Yang Qi Wang 《Earthquake Science》 CSCD 2009年第6期639-649,共11页
We simulate GPS horizontal velocity field in terms of rotations of crustal blocks to describe deformation behavior of the Chinese mainland and its neighboring areas. 31 crustal blocks are bounded primarily by -30 Quat... We simulate GPS horizontal velocity field in terms of rotations of crustal blocks to describe deformation behavior of the Chinese mainland and its neighboring areas. 31 crustal blocks are bounded primarily by -30 Quaternary faults with distinct geometries and variable long-term rates of 〈20 mm/a, and 1 683 GPS velocities were determined from decade-long observations mostly with an averaged uncertainty of 1-2 mm/a. We define GPS velocity at a site by the combination of motion of rigid block and elastic strain induced by the fault that is locking during a seismic cycle. Model velocities predicted from the preferable block model match well with the GPS velocities to an uncertainty of-l.7mm/a. The slip rates inferred from this model is in a range of 6-18 mm/a for the major faults in Tibet and its margins and 1-4 mm/a in eastern China, consistent with geological observations. Our numerical simulation suggests that the crustal blocks deform internally at a level of-10× 10^-9/a, quite small in comparison with significant deformation localized along fault zones of 50-100 km wide. We conclude that the pattern of continental deformation is not continuous-like but block-like, and the tenet of plate tectonics may be applicable to characterize the active deformation in Asia. 展开更多
关键词 GPS Chinese mainland active block block rotation crustal deformation
在线阅读 下载PDF
Re-delineating mountainous areas with three topographic parameters in Mainland Southeast Asia using ASTER global digital elevation model data 被引量:4
16
作者 XIAO Chi-wei LI Peng FENG Zhi-ming 《Journal of Mountain Science》 SCIE CSCD 2018年第8期1728-1740,共13页
Tropical mountainous areas not only provide substantial carbon storage and play an important role in global biological diversity, but also provide basic livelihood for a large number of poor ethnic minorities. However... Tropical mountainous areas not only provide substantial carbon storage and play an important role in global biological diversity, but also provide basic livelihood for a large number of poor ethnic minorities. However, there is no unified and explicit definition for mountainous areas. The local elevation range(LER) is a crucial structural parameter for delineating mountainous areas. However, current LER products are limited by the subjective selection of an optimum statistical window or coarser spatial resolution of topographical data. In this study, we presented an approach using thresholds for three topographic parameters, elevation, slope, and LER, derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM) to redelineate the vast mountainous areas of mainland Southeast Asia(MSEA). The mean change-point analysis method was applied to determine the optimum statistical window of the 1 arc second(approximately 30 m)-resolution GDEM LER. The results showed that: First, the optimum statistical window is 38 × 38 cell units(width × height) in a rectangular neighborhood, or an area of about 1.30 km^2 for calculating GDEM LER in MSEA. Second, the LER of more than 80% of the area ranges from 30 m to 499 m in MSEA. The LERs in the northern and northwestern MSEA are greater than their counterparts in the south and east. Third, the area of the re-delineated mountainous areas was 83.52 × 10~4 km^2, about 38.71% of the total area. Spatially, the mountainous areas are mainly distributed in the north and northeast of MSEA. The re-delineated 30-m resolution map of the mountainous areas will serve as a topographical dataset for monitoring mountainrelated land surface changes in MSEA. The parameter-modified mountain extraction procedure can be expanded to delineate global mountainous areas. 展开更多
关键词 Mountainous areas Local elevation range (LER) Statistical analysis Global digital elevation model mainland Southeast Asia(MSEA)
原文传递
Current horizontal strain field in Chinese mainland derived from GPS data 被引量:3
17
作者 杨国华 李延兴 +2 位作者 韩月萍 胡新康 巩曰沐 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第4期351-362,共12页
The current crustal horizontal strain field is given in the paper based on the horizontal movement rates obtained from about 400 GPS stations located in Chinese mainland and its surrounding areas. The results show: a)... The current crustal horizontal strain field is given in the paper based on the horizontal movement rates obtained from about 400 GPS stations located in Chinese mainland and its surrounding areas. The results show: a) The horizontal strain in Chinese mainland is strong in the west and weak in the east and the shear strain is larger than the normal strain (absolute magnitude). The general strain magnitude is 10-8/a and in local regions is 10-7/a, but the strain distribution is not homogeneous; b) The regions with the most significant NS-trending strains are the Himalayas belt along the western segment of Chinese southern boundary, the segment of 36N~42N along the western boundary and the northern margin of Qaidam block; c) The EW-trending strain variation along the western margin is the maximum and it is characterized by the alternatively positive and negative variations from the west to the east; d) The regions with larger magnitudes of REN (NE-trending shear strain) and Rmax (maximum shear strain) are Himalayas belt, the segment of 36N~42N along the western boundary, the western part of Qaidam block, Sichuan-Yunnan (Chuan-Dian) rhombic block and the border area of Alxa, Qilian and Tarim blocks; e) The surrounding area of Qinghai-Xizang (Qingzang) block is mainly superfacial contraction and its interior is basically superfacial expansion. The area to its north is mainly superfacial contraction with the maximum magnitude along the western boundary and the minimum magnitude in the eastern part (except Yanshan tectonic zone); f) In the west of the western part, the principal compressive strain is in the SN direction and the principal tensile strain is in the EW direction, while in the eastern margin area of the western part, the principal compressive strain is proximate EW and the principal tensile strain is about SN. The principal strain direction of Chuan-Dian rhombic block has changed greatly. In the northern part, it is compression in the EW and tension in the SN, while in the southern part, it is just the opposite; g) The strain pattern in Chinese mainland might be the integration of block mode and successive deformation mode. In addition, the shear strain might be the small-scale dominant strain. Such a result might be resulted from the collision of Indian plate and the boundaries coupling, and it is also closely related to the motion of deep-seated matters and the physical nature of crustal medium. Therefore, it should be noted that since the GPS stations are not homogenous in spatial distribution, the obtained strain fields and the scales of the strain should be different. 展开更多
关键词 GPS Chinese mainland current strain field strain mechanism
在线阅读 下载PDF
Detecting and mapping annual newly-burned plots(NBP) of swiddening using historical Landsat data in Montane Mainland Southeast Asia(MMSEA) during 1988–2016 被引量:6
18
作者 李鹏 封志明 +2 位作者 肖池伟 BOUDMYXAY Khampheng 刘宇 《Journal of Geographical Sciences》 SCIE CSCD 2018年第9期1307-1328,共22页
Swidden agriculture is by far the dominant land use system in the uplands of Southeast Asia (SEA), as well as other tropical regions, which plays an important role in the implementation of Reducing Emissions from De... Swidden agriculture is by far the dominant land use system in the uplands of Southeast Asia (SEA), as well as other tropical regions, which plays an important role in the implementation of Reducing Emissions from Deforestation and Forest Degradation (REDD) of United Nations. To our knowledge, the long-term inter-annual area of newly burned plots (NBP) of swidden agriculture in mainland Southeast Asia is still not available, let alone in the whole tropics. With the strengthening regional geo-economic cooperation in SEA, swidden agriculture has experienced and/or is still experiencing extensive and drastic transformations into other diverse market-oriented land use types since the 1990s. In this study, high-level surface reflectance products of Landsat 4151718 family sensors including Thematic Mapper (TM), Enhanced Thematic Mapper Plus (ETM+) and Operational Land Imager (OLI) acquired in March, April and May of each year between 1988 and 2016 were firstly utilized to detect and monitor the extent and area of NBP of swidden agriculture with multiple thresholds of four commonly-used vegetation indices, namely the Normalized Difference Vegetation Index (NDVI), Normalized Difference Moisture Index (NDMI), Normalized Burn Ratio (NBR) and Soil Adjusted Vegetation Index (SAVI), in combination with local phenological features of swid- dening and topographical data. The results showed that: (1) an annual average of 6.08×104 km2 of NBP of swidden agriculture, or 3.15% of the total land area of MSEA, were estimated in the past nearly three decades. (2) Annual NBP were primarily distributed in four major geomorphic units including the Central Range of Hills, Northern Mountainous Region, West- ern Myanmar Hills, and Annamite Chain. (3) A decadal average analysis indicated that the NBP of swidden agriculture opened year by year declined as a whole, especially after 2010, merely with an average of 5.23×104 km2. (4) The top ten provincial administrative units in Cambodia, Laos, Myanmar, Thailand and Vietnam, which consistently accounted for over 90% of the newly opened swiddens of each country, showed distinct fluctuations in usingslash-and-burn practices in the last decades. The Landsat-based (30 m) reconstructed 29-year longitudinal updated maps (including extent and area) of the NBP of swidden agri- culture may contribute to REDD and local livelihood related studies in Continental Southeast Asia. Our study further demonstrated that the multiple vegetative indices thresholds approach holds great potential in detecting swidden agriculture in tropical mountainous regions. 展开更多
关键词 swidden agriculture phenology newly-burned plots (NBP) LANDSAT Montane mainland SoutheastAsia (MMSEA)
原文传递
Structure and evolution of the submarine cable network of Chinese mainland 被引量:4
19
作者 XIE Yongshun WANG Chengjin HUANG Jie 《Journal of Geographical Sciences》 SCIE CSCD 2022年第5期932-956,共25页
Submarine cable network is one of the most important connectivity infrastructures in the digital era.In the past 20 years,the submarine cable network of Chinese mainland has formed a complex connectivity structure.Thi... Submarine cable network is one of the most important connectivity infrastructures in the digital era.In the past 20 years,the submarine cable network of Chinese mainland has formed a complex connectivity structure.This paper focuses on exploring the structure and evolution of the submarine cable network of Chinese mainland.The results show that the evolution can be divided into four stages:an initial stage(1993-1998),a developmental stage(1999-2002),a stagnation stage(2003-2015)and an accelerated stage(2016-2018).The connectivity structure can be analyzed at micro,meso and macro scales.Statistically,the connectivity increased significantly overall,but showed significant differences in space.For the microscale,the landing cities were characterized by“extensive but low,exclusive and high”;for the mesoscale,the connectivity of countries or regions was characterized by“distance attenuation”as a whole,but,in part,by a“regional identity”;for the macroscale,intercontinental connectivity differences have been declining.The hierarchy has been upgraded from a“3 system”to a“2+3 system”.Finally,this paper discusses the interaction between submarine cable network construction and international relations,and puts forward policy suggestions for China’s submarine cable construction. 展开更多
关键词 submarine cable network structure CONNECTIVITY EVOLUTION Chinese mainland
原文传递
Statistical features of aftershock distribution size for moderate and large earthquakes in Chinese mainland 被引量:3
20
作者 蒋海昆 郑建常 +3 位作者 吴琼 曲延军 李永莉 代磊 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第2期158-171,共14页
Based on data of earthquake sequences with Ms≥5.0 in Chinese mainland from 1970 to 2004, for different sequence types and different rupture modes of the main shock, the relationship between aftershock distribution si... Based on data of earthquake sequences with Ms≥5.0 in Chinese mainland from 1970 to 2004, for different sequence types and different rupture modes of the main shock, the relationship between aftershock distribution size R and the magnitude of the main shock Mo has been studied statistically. Considering the rupture mode of the main shock, we give the quantitative statistical relationships between R and Mo under 95% confidence level for different sequence typos. Qualitatively, lgR, the logarithm of the aftershock distribution size, is positively correlative to the M0, but the data distribution is dispersed. Viewing from different sequence typos, the correlation between R and M0 is very weak for isolated earthquake type (lET) sequence, R distributes in the range from 5 to 60 km; For mainshock-aftershock type (MAT), lgR is positively correlative to M0; For multiple main shock type (MMT), the corelation between lgR and M0 is not very obvious when M0≤6.2 and R distributes in the range from 5 to 70 km, while it shows a linear correlation when M0≥6.3. The statistical results also show that the occupational ratios of different sequence types for strike-slip and oblique slip are almost the same. But for dip-slip (mostly are thrust mechanisms), the ratio of MAT is higher than that of IET and MMT. Comparing with previous results, it indicates that, when M0 is large enough, R is mainly determined by M0 and there is almost no relationship with the rupture mode of the main shock. 展开更多
关键词 Chinese mainland aftershock distribution size types of aftershock sequences rupture mode ofthe main shock
在线阅读 下载PDF
上一页 1 2 148 下一页 到第
使用帮助 返回顶部