期刊文献+
共找到185,636篇文章
< 1 2 250 >
每页显示 20 50 100
Characteristics of transfer zones under the influence of preexisting faults and regional stress transformation:Wenchang A subsag,Zhujiang River Mouth Basin,northern South China Sea
1
作者 Wei LI Mingyue CAO +7 位作者 Meifang MENG Caiwei FAN Hui LI Jia LI Wanqiu WU Ruiqing QIN Xingan LI Yiming LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期744-759,共16页
A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon... A transfer zone in rift basins preserves important information on regional tectonic evolution and plays significant roles in hydrocarbon accumulation.Based on the systematic analysis of 3D seismic data and hydrocarbon accumulation conditions,the geometry,kinematics,and reservoir control of a large synthetic overlapping transfer zone in the south of the Wenchang A subsag in the Zhujiang(Pearl)River Mouth basin were investigated.Results indicate that the development and evolution of the transfer zone was controlled by the interaction between pre-existing faults and regional stress transformation.The intense rifting of the main faults of the transfer zone controlled the development of source rocks and faultcontrolled slope break paleogeomorphology.The strike-slip overprint since the Oligocene is conducive to the formation of a large-scale fault-anticline trap,and the secondary faults in the transfer zone contribute to the hydrocarbon transportation.The conjugate intersection area of the NE-and NW-trending faults offers more opportunity for hydrocarbon migration and accumulation. 展开更多
关键词 transfer zone pre-existing fault regional stress transformation CENOZOIC Wenchang A Subsag Zhujiang(Pearl)River Mouth Basin
下载PDF
A Study on the Path of Promoting External Dissemination of Regional Culture with Translation Technology under the Background of New Quality Productivity
2
作者 Juan Zhou 《Journal of Contemporary Educational Research》 2024年第8期26-31,共6页
With the introduction of the concept of new quality productivity characterized by high technology,efficiency,and quality,various industries in China have ignited a high spirit of innovation and development.Against thi... With the introduction of the concept of new quality productivity characterized by high technology,efficiency,and quality,various industries in China have ignited a high spirit of innovation and development.Against this background,this article analyzes the significance and current situation of the external dissemination of regional culture and combines the application of translation technology empowered by new quality productivity to explore a path suitable for the wider,more effective,and higher-quality external dissemination of regional culture.The aim is to provide practical experience for promoting the effective dissemination of regional culture in China to the world and better build a cultural power. 展开更多
关键词 New quality productivity regional culture External dissemination translation technology
下载PDF
基于Vision Transformer的车辆重识别模型优化
3
作者 张震 张亚斌 田鸿朋 《郑州大学学报(理学版)》 CAS 北大核心 2025年第1期46-52,共7页
针对车辆重识别任务中样本类内差异性大和类间相似度高的问题,提出了一种Vision Transformer框架下的车辆重识别方法。设计一种关键区域选择模块,整合Transformer中注意力分数矩阵,加强车辆的具有辨别性区域的关注程度,减小局部区域过... 针对车辆重识别任务中样本类内差异性大和类间相似度高的问题,提出了一种Vision Transformer框架下的车辆重识别方法。设计一种关键区域选择模块,整合Transformer中注意力分数矩阵,加强车辆的具有辨别性区域的关注程度,减小局部区域过度集中的注意力权重;构建一种包含对比损失和中心损失的混合损失函数,对比损失函数的引入增强了模型捕捉和比较样本之间的差异的能力,中心损失使得同一类别的样本更加紧密地聚集在一起,增强类间样本的区分度。实验结果验证了其有效性。 展开更多
关键词 车辆重识别 自注意力机制 注意力权重 区域选择
下载PDF
Atmospheric Sulfur and Nitrogen Deposition in Five Nature Reserves of Sichuan Basin to Qinghai-Tibetan Plateau Transect Region,Southwest-ern China
4
作者 XU Zhongjun SHU Xi +5 位作者 YANG Han FU Liqiang LIU Tingting XIA Zhonglin QIAO Xue TANG Ya 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1060-1072,共13页
Enhanced sulfur and nitrogen deposition has been observed in many transect regions worldwide,from urban/agricultural areas to mountains.The Sichuan Basin(SCB),with 18 prefectural cities,is the most economically-develo... Enhanced sulfur and nitrogen deposition has been observed in many transect regions worldwide,from urban/agricultural areas to mountains.The Sichuan Basin(SCB),with 18 prefectural cities,is the most economically-developed region in western China,while the rural Qinghai-Tibetan Plateau(QTP)lies west of the SCB.Previous regional and national atmospheric modeling studies have sug-gested that large areas in the SCB-to-QTP transect region experience excessive deposition of sulfur and nitrogen.In this study,we applied a passive monitoring method at 11 sites(one in urban Chengdu and 10 from fivenature reserves)in this transect region from September 2021 to October 2022 to confirm the high sulfur and nitrogen deposition fluxes and to understand the gaps between the modeling and observation results for this transect region.These observations suggest that the five reserves are under eutrophication risk,and only two reserves are partially under acidification risk.Owing to the complex topography and landscapes,both sulfur and nitrogen deposition and critical loads exhibit large spatial variations within a reserve,such as Mount Emei.Regional atmospheric modeling may not accurately capture the spatial variations in deposition fluxes within a reserve;however,it can capture general spatial patterns over the entire transect.This study demonstrates that a combination of state-of-the-art atmospheric chemical models and low-cost monitoring methods is helpful for ecological risk assessments at a regional scale. 展开更多
关键词 acid deposition ion exchange resin critical load ACIDIFICATION EUTROPHICATION Sichuan Basin to Qinghai-Tibetan Plateau transect region China
下载PDF
Spatiotemporal Variations and Regional Transport of Air Pollutants in Two Urban Agglomerations in Northeast China Plain 被引量:10
5
作者 LI Xiaolan HU Xiaoming +3 位作者 SHI Shuaiyi SHEN Lidu LUAN Lan MA Yanjun 《Chinese Geographical Science》 SCIE CSCD 2019年第6期917-933,共17页
Characteristics of air pollution in Northeast China(NEC) received less research attention in the past comparing to other heavily polluted regions in China.Spatiotemporal variations of six criteria air pollutants(PM10,... Characteristics of air pollution in Northeast China(NEC) received less research attention in the past comparing to other heavily polluted regions in China.Spatiotemporal variations of six criteria air pollutants(PM10, PM2.5, SO2, NO2, O3 and CO) in Central Liaoning Urban Agglomeration(CLUA) and Harbin-Changchun Urban Agglomeration(HCUA) in NEC Plain were analyzed in this study based on three-year hourly observations of air pollutants and meteorological variables from 2015 to 2017.The results indicated that the annual mean concentrations of air pollutants are generally higher in the middle and southern regions in NEC Plain and lower in the northern region.Megacities such as Shenyang, Harbin and Changchun experience severe air pollution, with a three-year averaged air quality index(AQI) larger than 80, far exceeding the daily AQI standard at the first-level of 50 in China.The annual mean PM and SO2 concentrations decrease most significantly in NEC urban agglomerations from 2015 to 2017, followed by CO and NO2, while O3 shows a slight increasing trend.All the six pollutants exhibit obvious seasonal and diurnal variations, and these variations are dictated by local emission and meteorological conditions.PM2.5 and O3 concentrations in NEC urban agglomerations strongly depend on wind conditions.High O3 concentrations at different cities usually occur in presence of strong winds but are independent on wind direction(WD), while high PM2.5 is usually accompanied by weak winds and poor dispersion condition, and sometimes also occur when the northerly or southerly winds are strong.Regional transport of air pollutants between NEC urban agglomerations is common.A severe haze event on November 1–4, 2017 is examined to demonstrate the role of regional transport on pollution. 展开更多
关键词 criteria air POLLUTANT METEOROLOGICAL condition regional transport urban AGGLOMERATION of NORTHEAST China
下载PDF
Assessment of the Biospheric Contribution to Surface Atmospheric CO_2 Concentrations over East Asia with a Regional Chemical Transport Model 被引量:6
6
作者 KOU Xingxia ZHANG Meigen +1 位作者 PENG Zhen WANG Yinghong 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第3期287-300,共14页
A regional chemical transport model,RAMS-CMAQ,was employed to assess the impacts of biosphere-atmosphere CO2 exchange on seasonal variations in atmospheric CO2 concentrations over East Asia.Simulated CO2 concentration... A regional chemical transport model,RAMS-CMAQ,was employed to assess the impacts of biosphere-atmosphere CO2 exchange on seasonal variations in atmospheric CO2 concentrations over East Asia.Simulated CO2 concentrations were compared with observations at 12 surface stations and the comparison showed they were generally in good agreement.Both observations and simulations suggested that surface CO2 over East Asia features a summertime trough due to biospheric absorption,while in some urban areas surface CO2 has a distinct summer peak,which could be attributed to the strong impact from anthropogenic emissions.Analysis of the model results indicated that biospheric fluxes and fossil-fuel emissions are comparably important in shaping spatial distributions of CO2 near the surface over East Asia.Biospheric flux plays an important role in the prevailing spatial pattern of CO2 enhancement and reduction on the synoptic scale due to the strong seasonality of biospheric CO2 flux.The elevation of CO2 levels by the biosphere during winter was found to be larger than 5 ppm in North China and Southeast China,and during summertime a significant depletion (≥ 7 ppm) occurred in most areas,except for the Indo-China Peninsula where positive bioflux values were found. 展开更多
关键词 CO2 regional transport modeling seasonal variation biospheric flux
下载PDF
Hub-and-Spoke System in Air Transportation and Its Implications to Regional Economic Development——A Case Study of United States 被引量:4
7
作者 SONG Wei MA Yanji 《Chinese Geographical Science》 SCIE CSCD 2006年第3期211-216,共6页
Considerable changes have taken place in commercial passenger air transport since the enactment of the 1978 Airline Deregulation Act in the US and the deregulation of airline networks that has occurred elsewhere. The ... Considerable changes have taken place in commercial passenger air transport since the enactment of the 1978 Airline Deregulation Act in the US and the deregulation of airline networks that has occurred elsewhere. The commercial and operational freedoms have led most of the larger carriers to develop hub-and-spoke networks, within which certain cities or metropolitan areas emerge as key nodes possessing tremendous advantages over other locations in the air transport system. This paper examines the nature of hub-and-spoke operations in air transportation services, and the benefits that accrue to a city or geographical region that is host to an airline hub. In particular, it looks into linkages between the air service hub and local economic development. Four potential types of impact of airports on the regional economy are defined and discussed. As an example, the assessment of the economic impacts of Cincinnati-Northern Kentucky International Airport (CVG), a major Delta Airlines hub, is introduced. 展开更多
关键词 Hub-and-Spoke System air transportation regional economic development
下载PDF
Effect of regional ecological carrying capacity on economic transformation 被引量:1
8
作者 WANG Shuo HU Zhen-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1522-1528,共7页
Combined with the actual situation of the western region city of Zunyi, the three subsystems including social, economic and natural environment evaluation index systems of ECC have been built based on the theory of ec... Combined with the actual situation of the western region city of Zunyi, the three subsystems including social, economic and natural environment evaluation index systems of ECC have been built based on the theory of ecological carrying capacity(ECC). In addition, the factor analysis method has been used and the influence factors on the ECC in the economic transition have been gained. The results show that factors of ECC in the three subsystems have different influence: 1) the natural subsystem, which contains factors on the ECC, has obvious limitation, and it has the greatest influence on industrial waste discharge per capita; 2) the social subsystem has a restriction on the ECC, which affects the traffic environment mostly; 3) the economic subsystem has a certain restriction on ECC, which has a large effect on the consumption level per capita. 展开更多
关键词 ECONOMIC transITION ECOLOGICAL carrying capacity (ECC) FACTOR analysis Chinese WESTERN region environmental engineering
下载PDF
Transformation from Comparative Advantage to Competitive Advantage——A Way to Improve Regional Agricultural Competitiveness 被引量:1
9
作者 SUN Neng-li College of Economics and Management,Huazhong Agricultural University,Wuhan 430070,China 《Asian Agricultural Research》 2011年第11期5-8,共4页
Primarily this paper analyses the internal correlation between comparative advantage and competitive advantage,and holds that there are no conflict and contradiction between the two,the industries with comparative adv... Primarily this paper analyses the internal correlation between comparative advantage and competitive advantage,and holds that there are no conflict and contradiction between the two,the industries with comparative advantage often easily to have strong competitive advantage.Then this paper analyses the factors influencing regional agricultural competitiveness,including resources endowment,ecological environment,quality of labour forces,infrastructure,technology innovation and transformation capacity,industrialization degree,relevant support industries,market demand structure,government management and policy and so on.Finally,based on the analysis of conversion mechanism of regional agriculture from comparative advantage to competitive advantage,this paper puts forward the countermeasures for promoting regional agricultural competitiveness as follows:vigorously develop agricultural industrialization,and foster the leading enterprises;improve the national policy system for supporting agriculture,and increase the inputs into infrastructure and scientific research innovation;promote the development of related industries and support industries,and promote agricultural competitiveness;increase consumers' demand for the quality of agricultural products,and propel business investment and innovation. 展开更多
关键词 COMPARATIVE ADVANTAGE COMPETITIVE ADVANTAGE region
下载PDF
Analysis on the Mode of Trans-Regional Allocation of Agricultural Machinery 被引量:2
10
作者 Li Liu Tong Chen +1 位作者 Shuguo Yang Xinli Wang 《American Journal of Plant Sciences》 2020年第7期1049-1056,共8页
With the continuous progress of agricultural technology, agricultural mechanization presents a good development trend after half a century development. But agricultural machinery equipment and the level of agricultura... With the continuous progress of agricultural technology, agricultural mechanization presents a good development trend after half a century development. But agricultural machinery equipment and the level of agricultural mechanization are imbalances in different regions</span><span style="font-family:Verdana;">;</span><span style="font-family:Verdana;"> the structure of agricultural machinery equipment is unreasonable</span><span style="font-family:Verdana;">;</span><span style="font-family:Verdana;"> there are great differences in agricultural mechanization level of different operations and different crops and the whole level of agricultural mechanization social service is not high. Through cross regional allocation of existing agricultural machinery</span><span style="font-family:Verdana;"> to</span><span style="font-family:Verdana;"> improve the working efficiency of agricultural machinery;we can extend the operation time of the agricultural machinery and improve the operation effect and income of agricultural machinery. 展开更多
关键词 Agricultural Machinery trans-regional Work Agricultural Machinery Allocation
下载PDF
A Case Study of Typical Regional Pollution Transport in Fuzhou City 被引量:1
11
作者 Wang Hong Xie Zuxin +1 位作者 Zheng Qiuping Li Yan 《Meteorological and Environmental Research》 CAS 2016年第3期15-18,26,共5页
Based on data of PM2.5 hourly concentration and HYSPLIT model backward trajectory in coastal cities of Fujian Province during January 25 -26, 2014, a typical regional pollution process affecting Fujian from the north ... Based on data of PM2.5 hourly concentration and HYSPLIT model backward trajectory in coastal cities of Fujian Province during January 25 -26, 2014, a typical regional pollution process affecting Fujian from the north to the south and the east to the west on January 26 was investiga- ted. Taking Fuzhou as an example, based on weather situation on the ground and at high altitudes as well as corresponding meteorological data such as wind direction, wind velocity, and visibility, the changes of meteorological elements before, during and after the pollution were compared. Based on the V-3θ atmospheric vertical structure diagrams, the weather reasons for the generation, maintaining and dissipation of the pollution were discussed. The results indicated that the regional pollution was transported from the northeast to the southwest. The northeasterly air flow in front of the cold ridge strengthened and moved toward the east, so that the pollutant from the north affected Fujian form the north to the south and from the east to the west. As a result, there was a dramatic increase of pollutant concentration, rapid drop of visibility, and deterioration of air quality in the affected areas. The heavy pollution process featured high-speed transport and short-time generation. The air quality changed from good state to heavy pollution in just 3 -4 hours. The maximum of IAQIpM2.5 reached 280. The whole pollution process lasted for 14 hours. Solar radiation had been deeply affected by aerosol clouds, so that atmospheric stratification was extremely stable. Along with the eastward movement of cold high pressure into the sea, the dominant wind direction near the ground changed from the northeast to the east, so that the source of the pollutant was cut off , and air quality quickly turned well. The changes of atmospheric vertical structure indicated that the high inversion layer and clouds near 700 hPa kept lower air clean and blocked upper pollution transport. The later sudden increase of wind speed and strengthening of atmospheric mechanical turbu- lent destroyed inversion layer, so that the upper pollutants invaded air near the ground rapidly. During the period of high pollution, the isothermal layer (aerosol clouds) leaded to decrease of wind speed, and the atmosphere became more stable. The pollution ended until the wind field changed. 展开更多
关键词 regional pollution transport Meteorological factors Atmospheric vertical structure HYSPLIT model backward trajectory China
下载PDF
Estimation of Regional Evapotranspiration in Alpine Area and Its Response to Land Use Change:A Case Study in Three-River Headwaters Region of Qinghai-Tibet Plateau,China 被引量:6
12
作者 LI Huixia LIU Guohua FU Bojie 《Chinese Geographical Science》 SCIE CSCD 2012年第4期437-449,共13页
Three-River Headwaters (TRH) region involved in this paper refers to the source region of the Changjiang (Yangtze) River, the Huanghe (Yellow) River and the Lancang River in China. Taking the TRH region of the Q... Three-River Headwaters (TRH) region involved in this paper refers to the source region of the Changjiang (Yangtze) River, the Huanghe (Yellow) River and the Lancang River in China. Taking the TRH region of the Qing- hai-Tibet Plateau as a case, the annual evapotranspiration (ET) model developed by Zhang et al. (2001) was applied to evaluate mean annual ET in the alpine area, and the response of annual ET to land use change was analyzed. The plant-available water coefficient (w) of Zhang's model was revised by using vegetation-temperature condition index (VTCI) before annual ET was calculated in alpine area. The future land use scenario, an input of ET model, was spa- tially simulated by using the conversion of land use and its effects at small regional extent (CLUE-S) to study the re- sponse of ET to land use change. Results show that the relative errors between the simulated ET and that calculated by using water balance equation were 3.81% and the index of agreement was 0.69. This indicates that Zhang's ET model based on revised plant-available water coefficient is a scientific and practical tool to estimate the annual ET in the al- pine area. The annual ET in 2000 in the study area was 221.2 ram, 11.6 mm more than that in 1980. Average annual ET decreased from southeast to northwest, but the change of annual ET between 1980 and 2000 increased from southeast to northwest. As a vast and sparsely populated area, the population in the TRH region was extremely unbalanced and land use change was concentrated in very small regions. Thus, land use change had little effect on total annual ET in the study area but a great impact on its spatial distribution, and the effect of land use change on ET decreased with in- creasing precipitation. ET was most sensitive to the interconversion between forest and unused land, and was least sen- sitive to the interconversion between cropland and low-covered grassland. 展开更多
关键词 evapotranspiration (ET) land use change plant-available water coefficient alpine area Three-RiverHeadwaters (TRH) region Qinghai-Tibet Plateau
下载PDF
Review of trans-Mediterranean power grid interconnection:a regional roadmap towards energy sector decarbonization 被引量:1
13
作者 Kaifeng Yu Paul van Son 《Global Energy Interconnection》 EI CAS CSCD 2023年第1期115-126,共12页
Climate change is becoming an important issue in all fields of infrastructure development.Electricity plays a core role in the decarbonized energy system’s path to a regional zero-emission pattern.A well-built trans-... Climate change is becoming an important issue in all fields of infrastructure development.Electricity plays a core role in the decarbonized energy system’s path to a regional zero-emission pattern.A well-built trans-Mediterranean backbone grid can hedge the profound evolution of regional power generation,transmission,and consumption.To date,only Turkey and the Maghreb countries(i.e.,Morocco,Algeria,and Tunisia)are connected with the Continental European Synchronous Area.Other south-and east-shore countries have insufficient interconnection infrastructures and synchronization difficulties that have proven to be major hurdles to the implementation of large-scale solar and wind projects and achievement of climate goals.This study analyzes the current trans-boundary grid interconnections and power and carbon emission portfolios in the Mediterranean region.To align with the recently launched new climate target‘Fit for 55’program and the accelerated large-scale renewables target,a holistic review of projected trans-Mediterranean grids and their market,technical,and financial obstacles of implementation was conducted.For south-and east-shore countries,major legal and regulatory barriers encompassing non-liberalized market structure,regulation gaps of taxation and transmission tariffs,and the private sector’s access rights need to be removed.Enhancement of domestic grids,substations,and harmonized grid codes and frequency,voltage,and communication technology standards among all trans-Mediterranean countries are physical prerequisites for implementing the Trans-Mediterranean Electricity Market.In addition,the mobilization of capital instruments along with private and international investments is indispensable for the realization of supranational transmission projects.As the final section of the decarbonization roadmap,the development of electric appliances,equipment,and vehicles with higher efficiency is inevitable in the decarbonized building,transportation,and industry sectors. 展开更多
关键词 Mediterranean Grid interconnection regional roadmap Power system Decarbonization Climate change
下载PDF
URBAN REGIONAL STRUCTURES TRANSFORMATION AND SUSTAINABLE DEVELOPMENT: CASE STUDY OF NANJING MEGALOPOLIS 被引量:1
14
作者 XU Yi-lun WU Qi-yan REN Dong-ming 《Chinese Geographical Science》 SCIE CSCD 2000年第4期32-38,共7页
s: Since 1978, many changes have happened on the background of urban regional structure in China, such as the economy system restructuring, the social transforming including the population flow accelerating and social... s: Since 1978, many changes have happened on the background of urban regional structure in China, such as the economy system restructuring, the social transforming including the population flow accelerating and social demand diversifying and individualizing, the political and economic systems reforms, the rise of the real estate market and the changing relationship between human and nature. From the macroscopic view, these changes make the national urban system to be a newer pattern with a widening gap among the cities in spite of the rising of the cities as a whole. At the same, the urban land use structures are changing with both the trends of intensification and diversification, and the trends of the regional diversification and the economic integration. Besides, urban structures with multiple centers are emerging in several metropolitan areas in China. These changes and trends mentioned above are confirmed by a case study of Nanjing City, a growing metropolitan area in east China. The case study also points out some problems in urban regional structure reforming, especially the poor social and ecological considerations. We should pay more attention to some ideas like balance of intensification and decentralization, development of suburban centers and a reasonable mixing of the functional activities to develop a sustainable urban regional structure. 展开更多
关键词 urban regional structure Nanjing megalopolis sustainable development
下载PDF
Research on the Impact of Industry Transfer to Regional Competitiveness 被引量:3
15
作者 Zhongping Wang 《Chinese Business Review》 2005年第10期38-40,共3页
In this paper the effects of industry transfer are discussed. Through analysis it can be found industry transfer will have important influence on the national competitiveness, regional competitiveness and enterprise c... In this paper the effects of industry transfer are discussed. Through analysis it can be found industry transfer will have important influence on the national competitiveness, regional competitiveness and enterprise competitiveness. It is found that industry transfer is an effective way to rejuvenate the old industrial base in the Northeast Region of China. 展开更多
关键词 industry transfer regional competitiveness life cycle
下载PDF
Statistical Transformation Indicators of Short-Term to Long-Term Using Flood Regional Coefficients (Case Study: East Azarbaijan Province, Iran)
16
作者 Iraj Ebn Abbas Maaroof Siosemarde 《Open Journal of Ecology》 2017年第1期34-40,共7页
Changing contexts in a long-term and short-term perspective should be managed within an integrated risk management framework that accounts for both temporary management strategies and permanent preventive measures to ... Changing contexts in a long-term and short-term perspective should be managed within an integrated risk management framework that accounts for both temporary management strategies and permanent preventive measures to reduce the impact of natural hazard processes. In this study, statistical transformation indicators of short-term (20 year) to long-term (30 year) used flood regional coefficients. After the tests of data validation and the reconstruction of missing and outlier data, the data of 18 hydrometric stations were completed for 30 years (1985 to 2014). In the next phase, the return period values were prepared for 20-year and 30-year statistical periods (1985 to 2004 and 1985 to 2014) using the HYFA software. Thus the 20-year to 30-year ratio for various return period discharges obtained and these dimensionless values were plotted for the return periods of 2, 5, 10, 20, 50 and 100 years, also fitted the logarithmic trend line and the values of coefficients of the relationship were obtained. The statistics including average, standard deviation, coefficient of variation (CV), skewness coefficient (CS) and Kurtosis coefficient (CK) were calculated for 20-year data period for each station and we identified the statistics as independent parameters and the coefficients of A and B as dependent parameter, thus analyzed using linear multivariate regression, and regional factors were obtained. In the hydrometric station with 17-027 code, the discharge using the regional factors was calculated and compared with the discharge values of 30 years data. The results showed that there is little difference between the observed and estimated values from regional factors thus this method can be used in projects that require at least 30 years of data. 展开更多
关键词 Factor Analysis FLOOD LONG-TERM SHORT-TERM regional Factors
下载PDF
Pricing Mechanism of China’s Trans-regional and Trans-provincial Electricity Trading
17
作者 Tian Xia ZhiYan Liu +1 位作者 Wei Xiong YongXiu He 《Energy and Power Engineering》 2013年第4期811-815,共5页
With the large-scale development of Chinese electric power, the contradiction of China’s energy supply and demand that reverse distributed is very prominent, therefore, promoting electricity trading is one of the imp... With the large-scale development of Chinese electric power, the contradiction of China’s energy supply and demand that reverse distributed is very prominent, therefore, promoting electricity trading is one of the important measures to get optimized configuration of energy resources in nationwide. For the two kinds of trading method, the “power point to the grid” trading and the “grid to grid” trading, this paper designed pricing mechanism model, and took one area as an example, we analyzed the impact of the participants by using different pricing mechanism, and put forward reasonable policy proposals for China’s pricing mechanism of trans-regional and trans-provincial electricity trading. 展开更多
关键词 trans-regional and trans-provincial ELECTRICITY TRADING Pricing Mechanism
下载PDF
Effects of kallikrein gene transfer on penumbral microvascular proliferation and on regional cerebral blood flow following cerebral ischemia/reperfusion injury
18
作者 Ruiyan Lu Qingyu Shen Lianhong Yang Mei Li Yidong Wang Ying Peng 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第10期1045-1050,共6页
BACKGROUND: Recent findings have demonstrated that the kallikrein-kinin system (KKS) participates in the pathological process of cerebral ischemia/reperfusion injury. Kallikrein gene transfer exhibits neural protec... BACKGROUND: Recent findings have demonstrated that the kallikrein-kinin system (KKS) participates in the pathological process of cerebral ischemia/reperfusion injury. Kallikrein gene transfer exhibits neural protective effects following cerebral infarction. OBJECTIVE: To observe the effects of kallikrein gene transfer on vascular proliferation in the peripheral infarct focus and on regional cerebral blood flow (rCBF) following cerebral ischemia/reperfusion injury. DESIGN, TIME AND SETTING: The completely randomized, controlled experiment was performed at the Lin Baixin Laboratory Center, the Second Affiliated Hospital of Sun Yat-sun University between September 2007 and April 2008. MATERIALS: pUCI9-HTK plasmid was constructed and maintained in the Laboratory for Neurology, the Second Affiliated Hospital of Sun Yat-sen University, China. Mouse anti-human kallikrein 1 monoclonal antibody was purchased from R&D Systems, USA. METHODS Ninety healthy, male, Sprague Dawley rats were used. Middle cerebral artery occlusion (MCAO) was established in all rats to induce cerebral ischemia/reperfusion injury. Following MCAO establishment, all rats were randomly divided into three groups (n = 30): blank control, saline, and pAdCMV-HTK. The saline and pAdCMV-HTK groups were stereotactically micro-injected with 5μL of physiological saline or with pAdCMV-HTK [multiplicity of infection (MOI) = 20], respectively, into the ischemic penumbra. In the blank control group, only sham injection was performed. MAIN OUTCOME MEASURES: At 12, 24, and 72 hours after treatment, cerebral infarction volume was measured by 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. Exogenous HTK expression, as well as regional vascular endothelial growth factor (VEGF) expression, was detected by immunohistochemistry. rCBF was examined by 14C-iodoantipyrine micro tracing. In addition, neurological severity score (NSS) was performed. Higher scores indicated more severe neurological deficits. RESULTS: NSS results demonstrated that compared with the saline and the blank control groups, the pAdCMV-HTK group exhibited lower NSSs 24 hours after pAdCMV-HTK injection (P 〈 0.05). The NSSs were further decreased after 72 hours (P 〈 0.01). Cerebral infarction volume at 24 hours, and in particular at 72 hours after treatment, was significantly reduced in the pAdCMV-HTK group compared with the blank control and saline groups (P 〈 0.05). The rCBF in the area surrounding the infarction lesion was slightly decreased in all groups compared with the contralateral area. At 24 and 72 hours following treatment, the rCBF in the peripheral infarction lesion was significantly elevated in the pAdCMV-HTK group compared with the blank control and saline groups (P 〈 0.05). Immunohistochemistry results revealed that VEGF-positive cells were primarily found in the cortex and in some white matter surrounding the cerebral infarction lesion. In addition, the expression of VEGF in the pAdCMV-HTK group was significantly higher compared with that in the blank control and saline groups at 12, 24, and 72 hours following treatment (P 〈 0.05). CONCLUSION: Following cerebral ischemia/reperfusion, kallikrein gene transfer can promote vascular proliferation in the brain tissue surrounding the infarction lesion, improve rCBF, and reduce infarction volume, thereby exhibiting protective effects to attenuate neurological deficits. 展开更多
关键词 cerebral ischemia ischemia/reperfusion injury ADENOVIRUS gene transfer KALLIKREIN vascular endothelial growth factor perfusion regional
下载PDF
Analysis of Asynchronism-Synchronism of Regional Precipitation in Inter-Basin Water Transfer Areas
19
作者 张强 王本德 李慧赟 《Transactions of Tianjin University》 EI CAS 2012年第5期384-392,共9页
The local characteristics of multi-dimensional modeling method of multivariate copula. A new modeling remedy this defect. Different types of copula distribution random variables are seldom considered in the general me... The local characteristics of multi-dimensional modeling method of multivariate copula. A new modeling remedy this defect. Different types of copula distribution random variables are seldom considered in the general method, called pair-copula construction, is introduced to functions are allowed to be introduced in this method. Correspondingly, the related characteristics of complex multivariate can be described by a cascade of pair-copula acting on two variables at a time. In the analysis of asynchronism-synchronism of regional precipitation in WED inter- basin water transfer areas, the pair-copula construction method is compared with the general modeling method of mul- tivariate copula. The results show that the local dependence structure would exist among hydrologic variables even in three-dimensional cases. In this situation, the general modeling method of multivariate copula would face difficulties in fitting distribution. However, the pair-copula construction method could capture the local information of hydrologic variables efficiently by introducing different types of copula distribution functions. Moreover, the compensation ca- pacity of water resources is strong in different hydrological areas of WED water transfer project. The asynchronous frequency of wetness and dryness is 69.64% and the favorable frequency for water transfer is 46.15%. 展开更多
关键词 PAIR-COPULA inter-basin water transfer asynchronism-synchronism of regional precipitation frequency analysis
下载PDF
Sino-Western Regional Differences and Translation
20
作者 ZHAO You-bin 《Journal of Literature and Art Studies》 2016年第4期441-444,共4页
Cultuare difference always exists in many aspects. Due to the national characters, regionalism, and times, translation can not be in a position when we try to translate without considering the language culture. Cultur... Cultuare difference always exists in many aspects. Due to the national characters, regionalism, and times, translation can not be in a position when we try to translate without considering the language culture. Cultural difference between English and Chinese, determines the different features between English and Chinese. 展开更多
关键词 Sino-Western cultures regional culture transLATION
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部