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The Islamic Studies in China:Research in the Field of History
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作者 Alimtohte Shiho 《Cultural and Religious Studies》 2024年第6期329-337,共9页
A history of the Islamic studies in China,not only includes studies on world Islam,it also includes research on Islam and Muslims in China.Before the Reform and Opening Up,China did not achieve much in this field,sinc... A history of the Islamic studies in China,not only includes studies on world Islam,it also includes research on Islam and Muslims in China.Before the Reform and Opening Up,China did not achieve much in this field,since then,the research field of Islam and Muslim in China has been expanding and the results have been published,forming a new trend.In this field,scholars such as Jin Yijiu,Li Xinghua,Qin Huibin,Zhou Guoli,Sha Qiuzhen,Zhou Xiefan,Wu Yungui,and Yang Huaizhong have made the most outstanding achievements.Especially in the collation of reference books and historical materials,in the past 20 years,The Encyclopedia of the history of Islam,The Chinese Encyclopedia of Islam have emerged,and the Chinese and World Encyclopedia of Islamic Law and other important historical books have been published.This paper focuses on the field of historical research and divided into academic research history at home and abroad,which is discussed from several fields such as general history,special history,national history,and regional history. 展开更多
关键词 islamic studies china the field of history Chinese islam world islam
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Influencing Factors and Prediction of Risk of Returning to Ecological Poverty in Liupan Mountain Region,China
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作者 CUI Yunxia LIU Xiaopeng +2 位作者 JIANG Chunmei TIAN Rujun NIU Qingrui 《Chinese Geographical Science》 SCIE CSCD 2024年第3期420-435,共16页
China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragil... China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragility and risk susceptibility have increased the risk of returning to ecological poverty.In this paper,the Liupan Mountain Region of China was used as a case study,and the counties were used as the scale to reveal the spatiotempora differentiation and influcing factors of the risk of returning to poverty in study area.The indicator data for returning to ecological poverty from 2011-2020 were collected and summarized in three dimensions:ecological,economic and social.The autoregressive integrated moving average model(ARIMA)time series and exponential smoothing method(ES)were used to predict the multidimensional indicators of returning to ecological poverty for 61 counties(districts)in the Liupan Mountain Region for 2021-2030.The back propagation neural network(BPNN)and geographic information system(GIS)were used to generate the spatial distribution and time variation for the index of the risk of returning to ecological poverty(RREP index).The results show that 1)ecological factors were the main factors in the risk of returning to ecological poverty in Liupan Mountain Region.2)The RREP index for the 61 counties(districts)exhibited a downward trend from 2021-2030.The RREP index declined more in medium-and high-risk areas than in low-risk areas.From 2021 to 2025,the RREP index exhibited a slight downward trend.From 2026 to2030,the RREP index was expected to decline faster,especially from 2029-2030.3)Based on the RREP index,it can be roughly divided into three types,namely,the high-risk areas,the medium-risk areas,and the low-risk areas.The natural resource conditions in lowrisk areas of returning to ecological poverty,were better than those in medium-and high-risk areas. 展开更多
关键词 risk of returning to ecological poverty autoregressive integrated moving average model(ARIMA) exponential smoothing model back propagation neural network(BPNN) Liupan Mountain Region china
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Study on the Law of Hydraulic Fracture Propagation in Low Permeability Thin Interbed Reservoir
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作者 YangJie Ou Hao Liang 《Engineering(科研)》 CAS 2023年第4期207-219,共13页
The third member of Weixinnanliu in the west of the South China Sea develops thin interbeds, and the vertical extension of fracturing fractures is excessive. Once the fractures extend vertically to the upper and lower... The third member of Weixinnanliu in the west of the South China Sea develops thin interbeds, and the vertical extension of fracturing fractures is excessive. Once the fractures extend vertically to the upper and lower aquifers, it is easy to cause water flooding of oil wells, and the effect after fracturing is not obvious. The present work aims to explore the longitudinal extension law of fractures in Low Permeability Thin Interbed Reservoir based on the finite element calculation platform. A three-dimensional expansion model of hydraulic fractures in the target reservoir was established, and the displacement, fracturing fluid viscosity, minimum horizontal principal stress difference, vertical stress, interlayer thickness, perforation point separation were studied. The interlayer distance and other factors affect the crack propagation law. The research results show that the thin interbed fractures have three forms: T-shaped fractures, through-layer fractures, and I-shaped fractures;for the target layer, the overlying stress is relatively large, and the minimum principal stress is along the horizontal direction. Vertical cracks;the farther the perforation point is or the greater the stress difference, the smaller the thickness of the interlayer required to control the fracture height;the stress difference is 3 MPa, and the distance between the perforation points exceeds 10 m, the thickness of the interlayer is required to be ≥4 m;In order to ensure that the width of the fracture in the middle spacer does not affect the placement of the proppant, it is recommended that the displacement be controlled within 3 m<sup>3</sup>/min and the viscosity of the fracturing fluid is 150 mPa·s;in addition, the thickness of the spacer required to control the fracture height is different due to different geological parameters. Different, different wells need targeted analysis. 展开更多
关键词 Western South china Sea Thin interbed Finite Element Crack propagation
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The Islamic Studies in China-Research in Political and Social Fields
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作者 Alimtohte Shiho 《Journal of Sociology Study》 2023年第2期98-102,共5页
In the research of political and social fields,modern Islamic politics has evolved into three schools of nationalism,modernism and fundamentalism in the 20th century.The research in the field of contemporary Islam inv... In the research of political and social fields,modern Islamic politics has evolved into three schools of nationalism,modernism and fundamentalism in the 20th century.The research in the field of contemporary Islam involves different countries,nationalities and different economic and political conditions.It is not only the research field of religion,but also has the characteristics of interdisciplinary academic frontier.From the perspective of academic research,these trends have attracted the attention and research of scholars inside and outside the church on Islamic political and social issues.Recently,there have been many problems related to Islam and the current international political life,as well as the research results of Islamic social thoughts and social movements. 展开更多
关键词 islamic studies china POLITICAL SOCIAL RESEARCH
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Study of the propagation direction of the internal waves in the South China Sea using satellite images 被引量:22
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作者 WANG Juan HUANG Weigen +2 位作者 YANG Jingsong ZHANG Huaguo ZHENG Gang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第5期42-50,共9页
Internal wave propagation carries considerable vertical shear which can lead to turbulence and mixing. Based on the analysis of more than 2 500 synthetic aperture radar (SAR) and optical satellite images, the in- te... Internal wave propagation carries considerable vertical shear which can lead to turbulence and mixing. Based on the analysis of more than 2 500 synthetic aperture radar (SAR) and optical satellite images, the in- ternal wave propagation in the whole South China Sea was investigated systematically. The results show that (1) in the northeastern South China Sea, most internal waves propagate westward from the Luzon Strait and are diffracted by coral reefs near the Dongsha Islands. Some impinge onto the shelf and a few are reflected; (2) in the northwestern South China Sea, most internal waves are generated at the shelf and propagate northwestward or westward to the coast; (3) in the western South China Sea, most internal waves propagate westward to the Vietnamese coast, except a few propagate southward to the deep sea; and (4) in the southern South China Sea, most internal waves propagate southwestward to the coast. Some prop- agate southeastward to the coast of Kalimantan Island, and a few propagate southeastward because of the influence of the Mekon~ River. 展开更多
关键词 remote sensing internal wave propagation South china Sea satellite images
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Modal structure and propagation of internal tides in the northeastern South China Sea 被引量:3
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作者 Qian Liu Xiaohui Xie +2 位作者 Xiaodong Shang Guiying Chen Hong Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第9期12-23,共12页
The evolution of energy, energy flux and modal structure of the internal tides (ITs) in the northeastern South China Sea is examined using the measurements at two moorings along a cross-slope section from the deep con... The evolution of energy, energy flux and modal structure of the internal tides (ITs) in the northeastern South China Sea is examined using the measurements at two moorings along a cross-slope section from the deep continental slope to the shallow continental shelf. The energy of both diurnal and semidiurnal ITs clearly shows a ~14-day spring-neap cycle, but their phases lag that of barotropic tides, indicating that ITs are not generated on the continental slope. Observations of internal tidal energy flux suggest that they may be generated at the Luzon Strait and propagate west-northwest to the continental slope in the northwestern SCS. Because the continental slope is critical-supercritical with respect to diurnal ITs, about 4.6 kJ/m^2 of the incident energy and 8.7 kW/m of energy flux of diurnal ITs are reduced from the continental slope to the continental shelf. In contrast, the semidiurnal internal tides enter the shelf because of the sub-critical topography with respect to semidiurnal ITs. From the continental slope to the shelf, the vertical structure of diurnal ITs shows significant variation, with dominant Mode 1 on the deep slope and dominant higher modes on the shelf. On the contrary, the vertical structure of the semidiurnal ITs is stable, with dominant Mode 1. 展开更多
关键词 SOUTH china SEA internal TIDES propagation scattering MODAL STRUCTURE
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Evolution and propagation of a mesoscale eddy in the northern South China Sea during winter 被引量:4
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作者 LIU Changjian DU Yan +2 位作者 ZHUANG Wei XIA Huayong XIE Qiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第7期1-7,共7页
In situ observations, satellite data, and the output from an eddy-resolving ocean circulation model were used to study the generations and propagations of an anticyclonic eddy in the northern South China Sea (NSCS) ... In situ observations, satellite data, and the output from an eddy-resolving ocean circulation model were used to study the generations and propagations of an anticyclonic eddy in the northern South China Sea (NSCS) during the winter of 2009-2010. In the NSCS, the anticyclonic eddy firstly appeared to the west of the Luzon Strait, migrated generally along the continental slope and dissipated around the Xisha Archipela- go. The evolution of the warm eddy contains three phases: development, maturation, and decay. The eddy mainly stayed near 119.7°E in December and then gradually moved to 118.7°E until January 15, when its intensity, as indicated by the thermocline temperature and salinity anomalies, increased significantly, re- flecting the growth of the eddy. The eddy reached its peak on January 15 and persisted until February 23. During this period, the eddy propagated westward to 116.4°E. After, the warm eddy weakened significantly and dissipated finally near the Xisha Archipelago. 展开更多
关键词 northern South china Sea anticyclonic eddy propagation
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Statistical analysis of mesoscale eddy propagation velocity in the South China Sea deep basin 被引量:4
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作者 Runqi Huang Lingling Xie +3 位作者 Quanan Zheng Mingming Li Peng Bai Keyi Tan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第11期91-102,共12页
Using mesoscale eddy trajectory product derived from satellite altimetry data from 1993 to 2017,this study analyzes the statistical characteristics of spatiotemporal distribution of mesoscale eddy propagation velociti... Using mesoscale eddy trajectory product derived from satellite altimetry data from 1993 to 2017,this study analyzes the statistical characteristics of spatiotemporal distribution of mesoscale eddy propagation velocities(C)in the South China Sea(SCS)deep basin with depths>1000 m.Climatologically,the zonal propagation velocities(cx)are westwards in the whole basin,and the meridional velocities(cy)are southwards in the northwestern basin,and northwards in the southeastern basin.The variation of cy with longitude is consistent with that of the background meridional currents with correlation coefficient R2 of 0.96,while the variation of cx is related both to the background zonal currents andβeffect.The propagation velocities characterize significant seasonality with the minimum magnitude occurring in summer and the maximum in winter for cx and C.Interannually,larger values of cx and cy mostly occurred in La Ni?a years in the negative phase of the Pacific Decadal Oscillation(PDO).Mesoscale eddies move fast at the beginning and end of their life span,i.e.,at their growth and dissipation periods,and slowly during their stable"midlife"period.This trend is negatively correlated with the rotating tangential velocity with R2 of–0.93.Eddies with extreme propagation velocities are defined,which are slower(faster)than 1.5 cm/s(15.4 cm/s)and take 1.5%(1.9%)of the total eddies.The extremely slow-moving(fastmoving)eddies tend to appear in the middle(on the edge)of the basin,and mostly occur in summer(winter).The mechanism analysis reveals that the spatiotemporal distributions of the propagation velocities of mesoscale eddies in the SCS are modulated by the basin-scale background circulation. 展开更多
关键词 South china Sea mesoscale eddies eddy propagation velocity variation in life span eddies with abnormal speeds
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Statistical characteristics of mesoscale eddies on the continental slope in the northern South China Sea 被引量:1
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作者 Zi Cheng Meng Zhou +3 位作者 Yisen Zhong Zhaoru Zhang Hailong Liu Lei Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第3期36-44,共9页
The continental slope in the northern South China Sea(SCS) is rich in mesoscale eddies which play an important role in transport and retention of nutrients and biota. In this study, we investigate the statistical prop... The continental slope in the northern South China Sea(SCS) is rich in mesoscale eddies which play an important role in transport and retention of nutrients and biota. In this study, we investigate the statistical properties of eddy distributions and propagation in a period of 24 years between 1993 and 2016 by using the altimeter data. A total of 147 eddies are found in the continental slope region(CSR), including 70 cyclonic eddies(CEs) and 77 anticyclonic eddies(ACEs). For those eddies that appear in the CSR, the surrounding areas of Dongsha Islands(DS) and southwest of Taiwan(SWT) are considered as the primary sources, where eddies generated contribute more than 60% of the total. According to the spatial distribution of eddy relative vorticity, eddies are weakening as propagating westward. Although both CEs and ACEs roughly propagate along the slope isobaths, there are discrepancies between CEs and ACEs. The ACEs move slightly faster in the zonal direction, while the CEs tend to cross the isobaths with large bottom depth change. The ACEs generally move further into the basin areas after leaving the CSR while CEs remain around the CSR. The eddy propagation on the continental slope is likely to be associated with mean flow at a certain degree because the eddy trajectories have notable seasonal signals that are consistent with the seasonal cycle of geostrophic current. The results indicate that the eddy translation speed is statistically consistent with geostrophic velocity in both magnitude and direction. 展开更多
关键词 the SOUTH china Sea CONTinENTAL SLOPE Dongsha ISLANDS EDDY statistics EDDY propagation
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ARTIFICIAL PROPAGATION AND BREEDING OF MARINE FISH IN CHINA 被引量:2
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作者 洪万树 张其永 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第1期41-51,共11页
Since the 1990s, artificial propagation and breeding technique of marine fish in China have developed by way of increasing species and fry numbers, with special stress laid on valuable species. Large quantities of art... Since the 1990s, artificial propagation and breeding technique of marine fish in China have developed by way of increasing species and fry numbers, with special stress laid on valuable species. Large quantities of artificial fry can meet the needs of both marine cage culture and pond culture for most species. Experimental results obtained by scientists have been put into use in actual production. Fish fry production has entered a period of sustainable development. So far, at least 44 species (21 families) of marine fish have been successfully bred in China. The artificial fry number of large yellow croaker (Pseudosciaena crocea) exceeded 300 million in 1999. The species whose artificial fry numbers have each surpassed 10 million annually are red drum (Sciaenops ocellatus), Japanese seabass (Lateolabrax japonicus), cuneate drum (Nibea miichthioides), spring spawning red seabream (Pagrosomus major) and threebanded sweetlip (Plectorhynchus cinctus). Millions of artificial fry are bred annually in the species of black porgy (Sparus macrocephalus), Russell’s snapper (Lutjanus russelli), javelin grunt (Pomadasys hasta), miiuy croaker (Miichthys miiuy) and skewband grunt (Hapalogenys nitens). The fish in the family Sciaenidae are the main species in artificial propagation and breeding. Some problems and prospects on marine fish culture and stock enhancement are also discussed and some proposals for sustainable development are put forward in this article. 展开更多
关键词 人工繁殖 饲养 鱼类 水产养殖
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Effect of the westward-propagating zonal wind anomaly on the initial development of quasi-biweekly oscillation over the South China Sea during early summer 被引量:1
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作者 CHEN Guang-Hua WANG Xu 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第1期89-95,共7页
以往许多研究揭示了夏季西太平洋及其南海地区准双周振荡纬向西传的传播特征。然而,本研究通过对南海初夏(5-6月)准双周振荡典型事件的合成分析发现,南海初夏准双周对流和经向风异常表现为局地变化的特征,而纬向风异常却表现为纬向西传... 以往许多研究揭示了夏季西太平洋及其南海地区准双周振荡纬向西传的传播特征。然而,本研究通过对南海初夏(5-6月)准双周振荡典型事件的合成分析发现,南海初夏准双周对流和经向风异常表现为局地变化的特征,而纬向风异常却表现为纬向西传特征。通过对准双周散度异常倾向的诊断分析,表明与纬向风异常相关的效应异常项领先于准双周散度异常,可以加强准双周对流及经向风异常的强度,从而促进南海夏初准双周振荡的初始发展。 展开更多
关键词 西传纬向风 准双周振荡 南海 初夏
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Study on the Efficient Cutting Propagation Technology for <i>Ilex</i>“China Girl”
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作者 Xiaobin Wang Yushu Lv +5 位作者 Shutang Xing Gang Liu Jingkai Sun Yaqiong Wang Cairu Wang Xiaoyan Yu 《American Journal of Plant Sciences》 2021年第10期1459-1467,共9页
In order to realize the efficient industrial production of <i>Ilex</i> “China Girl”, an orthogonal experiment with 4 factors and 3 levels was designed. Firstly, the optimal orthogonal cutting scheme was ... In order to realize the efficient industrial production of <i>Ilex</i> “China Girl”, an orthogonal experiment with 4 factors and 3 levels was designed. Firstly, the optimal orthogonal cutting scheme was selected from 9 treatments. Then through the systematic analysis of the effects of cutting position, substrate, exogenous hormones type and concentration on rooting indexes, such as rooting rate, root number, root length and root effect index, the theoretical optimal scheme was predicted and verified. The results showed that the theoretical optimal scheme (3000 mg/L IBA treatment for 15 s, cutting in mixed matrix with peat soil, perlite and vermiculite ratio of 2:1:1) was the optimal <span>cutting rooting scheme of <i>Ilex</i> “China Girl”. After the treatment of this sc</span>heme, the rooting rate of <i>Ilex</i> “China Girl” reached 100%, the average root number was 51.67 per plant, and the average root length was 6.13 cm. The rooting time was greatly shortened, the rooting rate and rooting effect were greatly improved. In this study, the efficient cutting propagation technology system of <i>Ilex</i> “China Girl” was established, which laid a foundation for the popularization and application of <i>Ilex</i> “China Girl”, and also provided reference for further improving the cutting propagation efficiency of other evergreen holly. This study laid a foundation for the application of <i>Ilex</i> “China Girl”, and also provided a reference for further improving the cutting propagation efficiency of other evergreen holly. 展开更多
关键词 Evergreen Holly Ilex china Girl” Cutting propagation Rooting index
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Circulation in the South China Sea is in a state of forced oscillation:Results from a simple reduced gravity model with a closed boundary
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作者 Rui Xin Huang Hui Zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第7期1-12,共12页
The South China Sea(SCS)is a narrow semi-enclosed basin,ranging from 4°–6°N to 21°–22°N meridionally.It is forced by a strong annual cycle of monsoon-related wind stress.The Coriolis parameter f ... The South China Sea(SCS)is a narrow semi-enclosed basin,ranging from 4°–6°N to 21°–22°N meridionally.It is forced by a strong annual cycle of monsoon-related wind stress.The Coriolis parameter f increases at least three times from the southern basin to the northern basin.As a result,the basin-cross time for the first baroclinic Rossby wave in the southern part of the basin is about 10-times faster than that in the northern part,which plays the most vitally important role in setting the circulation.At the northernmost edge of SCS,the first baroclinic Rossby wave takes slightly less than 1 year to move across the basin,however,it takes only 1–2 months in the southernmost part.Therefore,circulation properties for a station in the model ocean are not solely determined by the forcing at that time instance only;instead,they depend on the information over the past months.The combination of a strong annual cycle of wind forcing and large difference of basin-cross time for the first baroclinic Rossby wave leads to a strong seasonal cycle of the circulation in the SCS,hence,the circulation is dominated by the forced oscillations,rather than the quasi-steady state discussed in many textbooks.The circulation in the SCS is explored in detail by using a simple reduced gravity model forced by seasonally varying zonal wind stress.In particular,for a given time snap the western boundary current in the SCS cannot play the role of balancing mass transport across each latitude nor balancing mechanical energy and vorticity in the whole basin.In a departure from the steady wind-driven circulation discussed in many existing textbooks,the circulation in the SCS is characterized by the imbalance of mechanical energy and vorticity for the whole basin at any part of the seasonal cycle.In particular,the western boundary current in the SCS cannot balance the mass,mechanical energy,and vorticity in the seasonal cycle of the basin.Consequently,the circulation near the western boundary cannot be interpreted in terms of the wind stress and thermohaline forcing at the same time.Instead,circulation properties near the western boundary should be interpreted in terms of the contributions due to the delayed wind stress and the eastern boundary layer thickness.In fact,there is a clear annual cycle of net imbalance of mechanical energy and vorticity source/sink.Results from such a simple model may have important implications for our understanding of the complicated phenomena in the SCS,either from in-situ observations or numerical simulations. 展开更多
关键词 South china Sea ocean circulation annual cycle first baroclinic Rossby wave propagation western boundary current forced ossilation
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Die Stellung der Frauen im chinesischen Islam
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作者 胡梵 《西安翻译学院论坛》 2020年第4期57-64,共8页
Die aktuellen Verhaltmisse der chinesischen Musliminnen sind losgelost von der chinesisch-konfuzia-nischen Tradition und von der shari'a(Islamisches Gesetz)nicht angemessen zu verstehen.Dazu steht die Frage im Mit... Die aktuellen Verhaltmisse der chinesischen Musliminnen sind losgelost von der chinesisch-konfuzia-nischen Tradition und von der shari'a(Islamisches Gesetz)nicht angemessen zu verstehen.Dazu steht die Frage im Mittelpunkt,inwieweit die Modernisierung und der Globalisierungsprozess ihnen in den chinesischen Gesellschaften zu Gleichberechigung und zu mehr Handlungschancen und gesellshaftlichen Beteiligungsrechten verhelfen k8nnen.Die Tatsache ist,dass sich die Mehrheit der chinesischen Frauen in China immer noch in den Zwingen der traditio-nell chinesischen Moralprizipien und islamischen Geschlechterhierarchien bewegt.Es ist dies nicht nur eine Heraus-forderung fir die gesamte islamische Welt,sondern zugleich ein Vorzeichen,das Geschlechterverhaltnis in der Zu-kunft zu verbessern und die Gleichberechtigung von Mann und Frau zu verwirkichen. 展开更多
关键词 Fauen tellung Gecschecherverhaltnis islam china
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The propagation of seafloor spreading in the southwestern subbasin,South China Sea 被引量:34
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作者 LI JiaBiao DING WeiWei +2 位作者 WU ZiYin ZHANG Jie DONG ChongZhi 《Chinese Science Bulletin》 SCIE CAS 2012年第24期3182-3191,共10页
On the basis of the summary of basic characteristics of propagation, the dynamic model of the tectonic evolution in the South-western Subbasin (SWSB), South China Sea (SCS), has been established through high resolutio... On the basis of the summary of basic characteristics of propagation, the dynamic model of the tectonic evolution in the South-western Subbasin (SWSB), South China Sea (SCS), has been established through high resolution multi-beam swatch bathymetry and multi-channel seismic profiles, combined with magnetic anomaly analysis. Spreading propagates from NE to SW and shows a transition from steady seafloor spreading, to initial seafloor spreading, and to continental rifting in the southwest end. The spreading in SWSB (SCS) is tectonic dominated, with a series of phenomena of inhomogeneous tectonics and sedimentation. 展开更多
关键词 西南地区 海底扩张 南海海盆 中国南海 传播 构造演化 动态模型 地震剖面
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西南地区汛期降水次季节变化主模态的低频环流传播路径特征
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作者 白慧 严小冬 +1 位作者 池再香 王瑾 《山地气象学报》 2024年第1期10-20,共11页
【目的】该文探讨我国西南地区汛期(5—9月)降水次季节变化的主模态,以及中高纬和热带次季节波动如何影响该地区持续性异常低频降水,能为了解和预测西南地区汛期降水的次季节变化提供参考。【方法】利用西南地区111个地面气象站1961—2... 【目的】该文探讨我国西南地区汛期(5—9月)降水次季节变化的主模态,以及中高纬和热带次季节波动如何影响该地区持续性异常低频降水,能为了解和预测西南地区汛期降水的次季节变化提供参考。【方法】利用西南地区111个地面气象站1961—2015年逐日降水资料和JRA-55再分析环流场资料,采用EOF经验证交分解方法,分析西南地区汛期降水次季节变化主模态的低频环流特征和传播路径。【结果】西南地区汛期逐日降水主模态的空间分布为南北纬向型分布,空间特征向量高值区域分布在西南地区的南部和东南部,其高值区对应的SWDR与PC1的相关系数达0.991(通过0.05信度检验),PC1气候平均值的显著周期为12.9 d,且逐年PC1的显著周期主要集中在10~20 d时段,占比为60.0%;在PC1的典型低频年中,汛期季节内及其各分月的PC1均能较好地表征对应降水异常分布型的时间演变特征,且二者低频分量的正相关性更高(通过0.05信度检验),即PC1低频分量均能更好地把握SWDPI低频分量的准双周振荡特征,尤其在6、7和8月,这可能与影响主模态降水异常分布型的同期大气低频环流信号更为稳定有关;PC1的季节内变化不仅与中国东南部和南海形成的对流异常偶极子有关,还与在西南地区对流层高层形成的位势高度异常偶极子息息相关,该对流异常偶极子的形成与前期菲律宾以东OLR正异常的西北向传播和巴尔喀什湖东南部OLR负异常的东南向传播有关,并且菲律宾以东被抑制的对流向西北方向传播总是伴随着低层的局部反气旋,而西南地区的西南部对流的增强(抑制)总是伴随着高层北部的负(正)位势高度异常,同时,西南地区对流层高层的位势高度异常偶极子的形成,与中高纬对流层高层类似Rossby低频波列东南向传播过程中在青藏高原东侧顺时针转向有关。【结论】从气候背景看,影响PC1季节内变化的低频波列传播主要与2个方面的因子有关,一方面对流层高层西风急流轴主体位置南压和强度增强,通过影响中高纬类似Rossby低频波列的东传南下,从而影响在西南地区对流层高层形成位势高度异常偶极子型分布;另一方面印度季风槽的北抬加强了南海—菲律宾海域异常反气旋西北侧的西南气流,促使西南地区低层异常气旋形成,同时东亚季风槽增强也有利于热带西太平洋低频对流发展并向西北传播,从而影响在中国东南部和南海的形成的对流异常偶极子型分布。 展开更多
关键词 降水 次季节 低频环流 传播路径 西南地区
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南海西南海域中尺度涡传播特征分析
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作者 张舒妍 裘是 +2 位作者 郭佳祺 张哲恩 陈学恩 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期1-10,共10页
本文依据越南离岸流等将该海域分为南北两部分,基于1993年1月1日—2020年12月31日的海平面异常卫星高度计数据,追踪了南海西南海域中尺度涡的传播轨迹,研究了中尺度涡的传播特征。结果表明:北部区域气旋涡传播方向更易沿等深线传播,反... 本文依据越南离岸流等将该海域分为南北两部分,基于1993年1月1日—2020年12月31日的海平面异常卫星高度计数据,追踪了南海西南海域中尺度涡的传播轨迹,研究了中尺度涡的传播特征。结果表明:北部区域气旋涡传播方向更易沿等深线传播,反气旋涡更易跨地形由深水向浅水运动;北部区域冬半年(秋分至春分)会有更多的气旋涡偏北向运动,更多反气旋涡偏南向运动,夏半年(春分至秋分)则会有更多的反气旋涡偏北向运动,更多的气旋涡偏南向运动;南部区域夏半年反气旋涡的传播路径最为独特,主要向东北方向运动,气旋涡则主要向西南方向运动,二者方向完全相反。本文研究结果可为全面了解南海旋涡的传播及其物理机制提供支撑。 展开更多
关键词 南海西南海域 中尺度涡 传播特征 统计特征
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不同遮阴处理对小花山奈生长的影响
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作者 殷爱华 唐永锐 +3 位作者 刘强 李亭潞 植楚锋 冯莹 《福建农业科技》 CAS 2024年第2期36-41,共6页
为探究小花山奈的光照需求特性,为其在华南地区的栽培提供理论依据。在小花山奈块茎繁殖期间进行遮阴栽培试验,测量不同遮阴处理下小花山奈地下部分、地上部分的鲜重和干重,并得到月生长量、含水量和产量等数据。结果表明:在小花山奈生... 为探究小花山奈的光照需求特性,为其在华南地区的栽培提供理论依据。在小花山奈块茎繁殖期间进行遮阴栽培试验,测量不同遮阴处理下小花山奈地下部分、地上部分的鲜重和干重,并得到月生长量、含水量和产量等数据。结果表明:在小花山奈生长初期(7~8月),不同遮阴处理对小花山奈地上、地下部分的生长无显著影响;在小花山奈生长中期(9~10月),30%的遮阴处理有利于促进小花山奈地上、地下部分的生长;在小花山奈生长后期(11月~次年1月),30%的遮阴处理有利于促进小花山奈地上部分的生长,全光照有利于促进小花山奈地下部分的生长。小花山奈的地上部分迅速增长期集中在8~11月,地下部分迅速增长期集中在10~12月;适度的遮阴(30%遮阴度)处理有利于提高小花山奈的产量,但遮阴度太高(50%遮阴度)反而会大大降低小花山奈的产量。因此,在夏季给予30%遮阴处理、秋冬季给予全光照是小花山奈在华南地区种植的最佳光照模式。 展开更多
关键词 小花山奈 光照强度 生长特性 块茎繁殖 华南地区
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Scenario simulation and forecast of land use/cover in northern China 被引量:6
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作者 LI YueChen 1,2,3 & HE ChunYang 3 1 College of Geographical Science, Chongqing Normal University, Chongqing 400047, China 2 College of Resources and Environmental Science, Chongqing University, Chongqing 400044, China 3 College of Resources Science & Technology, Beijing Normal University, Beijing 100875, China 《Chinese Science Bulletin》 SCIE EI CAS 2008年第9期1401-1412,共12页
Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ec... Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern China in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern China. 展开更多
关键词 土地利用 中国北方 细胞自动机 系统动力学
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西南地区气象干旱向水文干旱传播的特征 被引量:7
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作者 石朋 唐汉 +3 位作者 瞿思敏 闻童 赵兰兰 李琼芳 《水资源保护》 EI CAS CSCD 北大核心 2023年第1期49-56,共8页
为了解西南地区气象干旱向水文干旱传播的特征,采用西南地区1968—2017年101个气象站观测资料和8个水文站月径流资料,计算了标准化降雨蒸散发指数(SPEI)和标椎化径流指数(SRI),基于皮尔逊相关系数(PCC)确定了干旱响应时间并结合游程理... 为了解西南地区气象干旱向水文干旱传播的特征,采用西南地区1968—2017年101个气象站观测资料和8个水文站月径流资料,计算了标准化降雨蒸散发指数(SPEI)和标椎化径流指数(SRI),基于皮尔逊相关系数(PCC)确定了干旱响应时间并结合游程理论识别、融合和剔除干旱事件,构建了线性干旱传播模型并确定了西南地区部分流域气象干旱向水文干旱传播的触发阈值。结果表明:西南地区干旱响应时间为2~7月;水文干旱敏感度分布与气象干旱传播率分布较为一致;干旱烈度传播阈值较小的流域,水文干旱事件历时更长。 展开更多
关键词 气象干旱 水文干旱 干旱特征 干旱传播 干旱响应时间 传播阈值 西南地区
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