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The Potential Contribution of Subsurface Drip Irrigation to Water-Saving Agriculture in the Western USA 被引量:19
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作者 T L Thompson PANG Huan-cheng LI Yu-yi 《Agricultural Sciences in China》 CSCD 2009年第7期850-854,共5页
Water shortages within the western USA are resulting in the adoption of water-saving agricultural practices within this region. Among the many possible methods for saving water in agriculture, the adoption of subsurfa... Water shortages within the western USA are resulting in the adoption of water-saving agricultural practices within this region. Among the many possible methods for saving water in agriculture, the adoption of subsurface drip irrigation (SDI) provides a potential solution to the problem of low water use efficiency. Other advantages of SDI include reduced NO3 leaching compared to surface irrigation, higher yields, a dry soil surface for improved weed control, better crop health, and harvest flexibility for many specialty crops. The use of SDI also allows the virtual elimination of crop water stress, the ability to apply water and nutrients to the most active part of the root zone, protection of drip lines from damage due to cultivation and tillage, and the ability to irrigate with wastewater while preventing human contact. Yet, SDI is used only on a minority of cropland in the arid western USA. Reasons for the limited adoption of SDI include the high initial capital investment required, the need for intensive management, and the urbanization that is rapidly consuming farmland in parts of the western USA. The contributions of SDI to increasing yield, quality, and water use efficiency have been demonstrated. The two major barriers to SDI sustainability in arid regions are economics (i.e., paying for the SDI system), including the high cost of installation; and salt accumulation, which requires periodic leaching, specialized tillage methods, or transplanting of seedlings rather than direct-seeding. We will review advances in irrigation management with SDI. 展开更多
关键词 subsurface drip irrigation (SDI) water-saving agriculture western usA
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Soil Fertility Survey in Western Usambara Mountains, Northern Tanzania 被引量:3
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作者 P. A. NDAKIDEMI J. M. R. SEMOKA 《Pedosphere》 SCIE CAS CSCD 2006年第2期237-244,共8页
Soil samples from thirty sites representing four agro-ecological zones in the Western Usambara Mountains (WUM) of the Lushoto District in northern Tanzania were collected and analyzed for different nutrients. The resu... Soil samples from thirty sites representing four agro-ecological zones in the Western Usambara Mountains (WUM) of the Lushoto District in northern Tanzania were collected and analyzed for different nutrients. The results suggested that the major soil fertility constraint was P deficiency. On the basis of critical levels established in other areas, 90% of the soils were ranked as P deficient. This was followed by N, which was ranked as inadequate in 73% of the sites. Magnesium, K, and Ca also appeared limiting with 67%, 53% and 50% of the soils falling below the established critical values, respectively. A few soils (10%) were also found to contain exchangeable Al. The metallic micronutrients (Cu, Fe, and Zn) were adequate in all soils. Two sites had excessive Mn that could lead to toxicity in crops, and one was Mn deficient. 展开更多
关键词 agro-ecological zone P deficiency soil fertility western usambara Mountains
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A bruptchanges in an 8000-year precipitationreconst ruction for Nevada,the Western USA 被引量:1
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作者 GU Xiangqian JIANC Jianmin +1 位作者 Franklin SCHWING Roy MENDELSSOHN 《Journal of Geographical Sciences》 SCIE CSCD 2005年第3期259-272,共14页
A scanning t-test algorithm for detecting multiple time-scale abrupt changes in the level of a time-series was used to analyze an 8000 year time series of annual precipitation which was reconstructed from tree rings f... A scanning t-test algorithm for detecting multiple time-scale abrupt changes in the level of a time-series was used to analyze an 8000 year time series of annual precipitation which was reconstructed from tree rings for the Nevada Climate Division 3 in the western USA. The tree ring samples were gathered from eight states in the southwestern USA. Twenty-two change-points were identified by the algorithm and these were used to partition the tree-ring series into twenty-three relatively Wet/Normal/Dry episodes. These twenty-three episodes were collaborated by a coherency analysis of abrupt changes between the precipitation reconstruction series and the TIC/δ^18O records from cored sediments of Pyramid Lake in Nevada, and by comparison with published results from related studies. These episodes were also compared with studies of the global climate change and with records of climate change in China during the same periods. The results suggest that the precipitation reconstruction series is quite valuable for climate-change research on multi-centurial time-scales in the western USA, and that the scanning t-test and coherency detection algorithms may have a wide use for detecting multiple time-scale abrupt changes in a long time series. As the TIC and δ^18O record series are high resolution with unequal sampling intervals ranging between 3 and 14 years, a new algorithm was developed to deal with the unequal time intervals in the series. 展开更多
关键词 abrupt change 8000 years precipitation reconstruction tree ring western usA
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A comparison of tectonic ambient shear stress value in China with that in western USA
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作者 陈培善 白彤霞 李保昆 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第5期503-509,共7页
A method is proposed to estimate average tectonic ambient shear stress value for a region. Thus the average stress values of 19 regions in western USA, and 43 regions (each region is 1010) in Chinese mainland and its ... A method is proposed to estimate average tectonic ambient shear stress value for a region. Thus the average stress values of 19 regions in western USA, and 43 regions (each region is 1010) in Chinese mainland and its surroundings have been obtained. The data of 15 993 earthquakes are from the Internet Centroid Moment Tensor solution made by Harvard University from 1997 to 1999. The results demonstrate that there are highest average stress values in the regions of south California of USA and its off coast sea, reach to 12.0 MPa and 13.7 MPa respectively, then gradually decrease toward north, south, and east. The lowest value is 8.7 MPa and 63% of highest value. The average stress values in northern Xinjiang and in the Chayu region of Tibet are 17.2 and 12.9 MPa respectively. They are highest values in China and higher than USAs. The average stress value in North China, Yunnan, Sichuan, Taiwan is similar to south California of USA. The average stress value in South-North seismic zone is about 13 MPa, a little higher than south California. The distribution of average stress value for two important regions provides basic data for geology. These results are useful to research earthquake activity background and attenuation relation of strong ground motion parameters (e.g. peak acceleration and response spectra). 展开更多
关键词 average tectonic ambient shear stress value comparison of average stress value Chinese mainland and its surroundings western usA
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Quantitative effect of kerogen type on the hydrocarbon generation potential of Paleogene lacustrine source rocks,Liaohe Western Depression,China 被引量:1
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作者 Sha-Sha Hui Xiong-Qi Pang +7 位作者 Fu-Jie Jiang Chen-Xi Wang Shu-Xing Mei Tao Hu Hong Pang Min Li Xiao-Long Zhou Kan-Yuan Shi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期14-30,共17页
Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source rocks.Lacustrine source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organ... Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source rocks.Lacustrine source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organic carbon(TOC)content,various kerogen types,and a wide range of thermal maturity.Consequently,their hydrocarbon generation potential and resource estimation can be misinterpreted.In this study,geochemical tests,numerical analysis,hydrocarbon generation kinetics,and basin modeling were integrated to investigate the differential effects of kerogen types on the hydrocarbon generation potential of lacustrine source rocks.Optimized hydrocarbon generation and expulsion(HGE)models of different kerogen types were established quantitatively upon abundant Rock-Eval/TOC/vitrinite reflectance(R_(o))datasets.Three sets of good-excellent source rocks deposited in the fourth(Es4),third(Es3),and first(Es1)members of Paleogene Shahejie Formation,are predominantly types I-II_(1),II_(1)-II_(2),and II-III,respectively.The activation energy of types I-II_(2)kerogen is concentrated(180-230 kcal/mol),whereas that of type III kerogen is widely distributed(150-280 kcal/mol).The original hydrocarbon generation potentials of types I,II_(1),II_(2),and III kerogens are 790,510,270,and 85 mg/g TOC,respectively.The Ro values of the hydrocarbon generation threshold for type I-III source rocks gradually increase from 0.42%to 0.74%,and Ro values of the hydrocarbon expulsion threshold increase from 0.49%to 0.87%.Types I and II_(1)source rocks are characterized by earlier hydrocarbon generation,more rapid hydrocarbon expulsion,and narrower hydrocarbon generation windows than types II_(2)and III source rocks.The kerogen types also affect the HGE history and resource potential.Three types(conventional,tight,and shale oil/gas)and three levels(realistic,expected,and prospective)of hydrocarbon resources of different members in the Liaohe Western Depression are evaluated.Findings suggest that the Es3 member has considerable conventional and unconventional hydrocarbon resources.This study can quantitatively characterize the hydrocarbon generation potential of source rocks with different kerogen types,and facilitate a quick and accurate assessment of hydrocarbon resources,providing strategies for future oil and gas exploration. 展开更多
关键词 Kerogen type Hydrocarbon generation potential Lacustrine source rocks Liaohe western depression
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Geophysical and Crustal Movement Characteristic of Western Sichuan Basin
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作者 ZHOU Wenyue SUN Yanyun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期98-100,共3页
Analysis and research of large complex phenomena before and after the devastating earthquake to reduce the threat of natural disasters to human survival environment is of great significance.This paper analyzes the Wen... Analysis and research of large complex phenomena before and after the devastating earthquake to reduce the threat of natural disasters to human survival environment is of great significance.This paper analyzes the Wenchuan earthquake zone characteristics of gravity anomaly distributions,and then use edge detection and Euler deconvolution method to inverse Longmenshan gravity anomaly before earthquake.Fault distribution features and the general depth about the fault top of Longmenshan and its adjacent area before earthquake has been obtained.Morphology difference and possible earthquake formation have been analyzed through the Euler deconvolution result of gravity anomaly profile before and after the earthquake. 展开更多
关键词 edge detection gravity anomaly morphology difference western Sichuan Basin
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Morphological and molecular description of a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii sp.nov.(Diptera:Psychodidae)from Western Ghats,India
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作者 Prasanta Saini Harish Kumar Shah +3 位作者 Mathew Jessu Sonia T Tom Anns KP Amju 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第5期226-234,共9页
Objective:To report a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii sp.nov.(Diptera:Psychodidae)from Western Ghats,India.Methods:A systematic sandfly survey was conducted in the Thrissur and Kollam distr... Objective:To report a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii sp.nov.(Diptera:Psychodidae)from Western Ghats,India.Methods:A systematic sandfly survey was conducted in the Thrissur and Kollam districts of Kerala,India using mechanical aspirators,light and sticky traps,both indoor and outdoor habitats,for a period of one year.Deoxyribonucleic acid barcoding of samples was performed targeting mitochondrial cytochrome oxidase I(COI)gene and sequence generated was subjected to phylogenetic analysis.Results:Sergentomyia(Neophlebotomus)ashwanii,a new sandfly species is recorded and described in this communication.A single row of 10-12 pointed teeth in the cibarium with 4-6 small denticles or fore-teeth are the key characteristics that is distinctive from other members of the subgenus Neophlebotomus.Mitochondrial COI barcode followed by phylogenetic analysis of the nucleotide sequence confirms that specimens of the species belong to the same taxonomic group while the genetic distance(14.2%)with the congeners established it to be a different species.Conclusions:The Western Ghats'being an important biodiversity hotspot and has dearth of systematic entomological surveys on sandflies.The current study tried to fill the void and also report a new sandfly species. 展开更多
关键词 Sergentomyia(Neophlebotomus)ashwanii COI barcode western Ghats Phlebotomine sandflies
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Impact of typical environments in China’s western mountainous areas on the durability of railway concrete:a review
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作者 Jiahe Wang Yanbin Tan +3 位作者 Huajian Li Xinhua Zhong Jiaxuan Wang Yu Gao China 《Railway Sciences》 2024年第5期650-669,共20页
Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodolog... Purpose–This study aims to analyze the impact mechanism of typical environments in China’s western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodology/approach–With the continuous promotion of infrastructure construction,the focus of China’s railway construction has gradually shifted to the western region.The four typical environments of large temperature differences,strong winds and dryness,high cold and low air pressure unique to the western mountainous areas of China have adverse effects on the durability of typical railway structure concrete(bridges,ballastless tracks and tunnels).This study identified the characteristics of four typical environments in the western mountainous areas of China through on-site research.The impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research;Finally,a strategy for improving the durability of railway concrete suitable for the western mountainous areas of China was proposed.Findings–The daily temperature difference in the western mountainous areas of China is more than twice that of the plain region,which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless tracks.It will result in cracking.The wind speed in the western plateau region is about 2.5 to 3 times that of the plain region,and the average annual rainfall is only 1/5 of that in the plain region.The drying effect on the surface of casting concrete will significantly accelerate its cracking process,leading to serious durability problems.The environmental temperature in the western mountainous areas of China is generally low,and there are more freeze-thaw cycles,which will increase the risk of freeze-thaw damage to railway concrete.The environmental air pressure in the western plateau region is only 60%of that in the plain region.The moisture inside the concrete is more likely to diffuse into the surrounding environment under the pressure difference,resulting in greater water loss and shrinkage deformation of the concrete in the plateau region.The above four issues will collectively lead to the rapid deterioration of concrete durability in the western plateau region.The corresponding durability improvement suggestions from theoretical research,new technology development and standard system was proposed in this paper.Originality/value–The research can provide the mechanism of durability degradation of railway concrete in the western mountainous areas of China and corresponding improvement strategies. 展开更多
关键词 western mountainous areas CONCRETE DURABILITY ENVIRONMENT
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Utility of fluid inclusion paleo-temperature in petroleum system modelling:A case study from western offshore,India
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作者 V.Nandakumar S.Shivapriya Silpa Thankan 《Energy Geoscience》 EI 2024年第2期101-119,共19页
The paleo-temperature(Th)data from fluid inclusions are utilized for thermal history modelling using PetroMod software.Generally,bottom hole temperature(BHT)and vitrinite reflectance(Ro)measurements are widely used in... The paleo-temperature(Th)data from fluid inclusions are utilized for thermal history modelling using PetroMod software.Generally,bottom hole temperature(BHT)and vitrinite reflectance(Ro)measurements are widely used in petroleum system modelling(PSM)in the oil industry for calibration purposes.Th representing the minimum temperature of fluid entrapment estimated from fluid-inclusion study provides extra support to build the thermal models for PSM.Fluid inclusion parameters along with Rock-Eval pyrolysis analysis have been used to predict the maturity of oil in terms of API gravity as well as the maturity of source rocks respectively.Two exploratory wells RV-1(Mumbai Offshore Basin)and KK4C-A-1(Kerala-Konkan Offshore Basin),India were examined and the T_(h)from most of the fluid inclusions of wells RV-1 and KK4C-A-1 fell in the oil window range of 60-140℃suggesting thermal conditions favourable for oil generation in both of the wells.T_(h)of coeval aqueous inclusions along with the Hydrocarbon Fluid inclusions(HCFIs)was used to calibrate PSM.Vital parameters show that source rocks of well RV-1 are mature and that of well KK4C-A-1 are immature.Two sets of PSM are created in terms of generation and expulsion for the dry wells RV-1 and KK4C-A-1 and calibrated each well using fluid inclusion Th and BHT.From the fluid inclusion analysis method,it is evident that hydrocarbon generation happened in both wells and the paleo-temperature indicates that the formations of both wells were subjected to temperatures in the oil window range,even though it was designated as dry wells in the present scenario.The present study highlights the application of fluid inclusion paleo-temperature(Th)during calibration instead of commonly used methods.We could obtain desirable and accurate data output from PSM using T_(h) calibration. 展开更多
关键词 Paleo-temperature(T_(h)) Hydrocarbon fluid inclusion Petroleum system modelling Petroleum generation and expulsion western offshore basin
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The Impact of Western Scholars on the Music Education of the Jingpo Ethnic Group in Yunnan,China
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作者 Kaili Lei 《Journal of Contemporary Educational Research》 2024年第11期56-62,共7页
This research attempts to uncover the influence of Western scholars’activities on music education in the Jingpo areas of Dehong Dai-Jingpo Autonomous Prefecture in western Yunnan,China,during the early 20th century.T... This research attempts to uncover the influence of Western scholars’activities on music education in the Jingpo areas of Dehong Dai-Jingpo Autonomous Prefecture in western Yunnan,China,during the early 20th century.The differences exist in the cultures,languages,and beliefs of the various ethnic groups in Yunnan.As such,systematic basic education is difficult to carry out in order,especially music education.However,this phenomenon changed in the early 20th century with the arrival of Western scholars.This study will analyze existing literature and data collected in fieldwork to trace the origins of Western music education in the Jingpo areas.In addition,the study intends to explore the localized and modernized music education model used by Western scholars for Jingpo.Furthermore,this research may help broaden the understanding of minority communities to the development of music education policies that precede the implementation of regulations.Additionally,it seeks to raise awareness of the music of ethnic minority groups worldwide and to achieve equality of musical education resources in ethnic minority areas as much as possible. 展开更多
关键词 western music Jingpo Music education LOCALIZATION MODERNIZATION
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Lithium-bearing Pegmatite Exploration in Western Altun,Xinjiang,using Remote-Sensing Technology 被引量:4
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作者 JIANG Qi DAI Jingjing +2 位作者 WANG Denghong WANG Chenghui TIAN Shufang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期681-694,共14页
Western Altun in Xinjiang is an important area,where lithium(Li)-bearing pegmatites have been found in recent years.However,the complex terrain and harsh environment of western Altun exacerbates in prospecting for Li-... Western Altun in Xinjiang is an important area,where lithium(Li)-bearing pegmatites have been found in recent years.However,the complex terrain and harsh environment of western Altun exacerbates in prospecting for Li-bearing pegmatites.Therefore,remote-sensing techniques can be an effective means for prospecting Li-bearing pegmatites.In this study,the fault information and lithologyical information in the region were obtained using the median-resolution remotesensing image Landsat-8,the radar image Sentinel-1 and hyperspectral data GF-5.Using Landsat-8 data,the hydroxyl alteration information closely related to pegmatite in the region was extracted by principal component analysis,pseudoanomaly processing and other methods.The high spatial resolution remote-sensing data WorldView-2 and WorldView-3 short-wave infrared images were used and analyzed by principal component analysis(PCA),the band ratio method and multi-class machine learning(ML),combined with conventional thresholds specified the algorithms used to automatically extract Li-bearing pegmatite information.Finally,the Li-bearing pegmatite exploration area was determined,based on a comprehensive analysis of the faults,hydroxyl alteration lithology and Li-bearing pegmatite information.Field investigations have verified that the distribution of pegmatites in the central part of the study area is consistent with that of Li-bearing pegmatites extracted in this study.This study provides a new technique for prospecting Li-bearing pegmatites,which shows that remote-sensing technology possesses great potential for identifying lithium-bearing pegmatites,especially in areas that are not readily accessible. 展开更多
关键词 remote sensing prospecting multi-class machine learning Li-bearing pegmatites western Altun
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Expert consensus on diagnosis and treatment of ulcerative colitis with integrated traditional Chinese and Western medicine:A nursing perspective 被引量:1
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作者 Bing XU Miao LIU +3 位作者 Hairong HU Jing ZHANG Yanping HUANG Ling TANG 《Journal of Integrative Nursing》 2023年第1期1-7,共7页
Ulcerative colitis(UC)is a chronic nonspecific intestinal inflammatory disease of unclear etiology,characterized by continuous and diffuse inflammatory changes of colorectal mucosa.In recent years,the incidence rate o... Ulcerative colitis(UC)is a chronic nonspecific intestinal inflammatory disease of unclear etiology,characterized by continuous and diffuse inflammatory changes of colorectal mucosa.In recent years,the incidence rate of UC in China has increased year by year,but there is no effective cure method in Western medicine.Traditional Chinese medicine treatment based on syndrome differentiation has the unique advantages of simplicity,convenience,effectiveness,and low cost.Therefore,integration of Chinese and Western medicine has become an important strategy for UC diagnosis and treatment,and has made significant progress in UC.On the basis of learning from a number of consensuses at home and abroad,combined with Chinese research results and the actual clinical situation of traditional Chinese and Western medicine,the UC group of the Chinese Association of Integrative Medicine has formulated the expert consensus on the diagnosis and treatment of UC with integrated traditional Chinese and Western medicine.In this consensus,the pathogenesis,etiology and pathogenesis,diagnosis,integrated traditional Chinese and Western medicine treatment,and chronic disease management with integrated traditional Chinese and Western medicine for UC were recommended by experts.This article interprets the consensus from the perspective of nursing in order to provide reference basis for clinical nursing workers. 展开更多
关键词 CONSENSus continuing care integrated traditional Chinese and western medicine nursing nursing perspective traditional Chinese medicine ulcerative colitis
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A Physics-informed Deep-learning Intensity Prediction Scheme for Tropical Cyclones over the Western North Pacific 被引量:1
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作者 Yitian ZHOU Ruifen ZHAN +4 位作者 Yuqing WANG Peiyan CHEN Zhemin TAN Zhipeng XIE Xiuwen NIE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1391-1402,共12页
Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a ti... Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a time-dependent theory of TC intensification,termed the energetically based dynamical system(EBDS)model,together with the use of a long short-term memory(LSTM)neural network.In time-dependent theory,TC intensity change is controlled by both the internal dynamics of the TC system and various environmental factors,expressed as environmental dynamical efficiency.The LSTM neural network is used to predict the environmental dynamical efficiency in the EBDS model trained using besttrack TC data and global reanalysis data during 1982–2017.The transfer learning and ensemble methods are used to retrain the scheme using the environmental factors predicted by the Global Forecast System(GFS)of the National Centers for Environmental Prediction during 2017–21.The predicted environmental dynamical efficiency is finally iterated into the EBDS equations to predict TC intensity.The new scheme is evaluated for TC intensity prediction using both reanalysis data and the GFS prediction data.The intensity prediction by the new scheme shows better skill than the official prediction from the China Meteorological Administration(CMA)and those by other state-of-art statistical and dynamical forecast systems,except for the 72-h forecast.Particularly at the longer lead times of 96 h and 120 h,the new scheme has smaller forecast errors,with a more than 30%improvement over the official forecasts. 展开更多
关键词 tropical cyclones western North Pacific intensity prediction EBDS LSTM
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Natural gas exploration potential and favorable targets of Permian Fengcheng Formation in the western Central Depression of Junggar Basin,NW China 被引量:1
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作者 TANG Yong HU Suyun +4 位作者 GONG Deyu YOU Xincai LI Hui LIU Hailei CHEN Xuan 《Petroleum Exploration and Development》 SCIE 2024年第3期563-575,共13页
Based on the organic geochemical data and the molecular and stable carbon isotopic compositions of natural gas of the Lower Permian Fengcheng Formation in the western Central Depression of Junggar Basin,combined with ... Based on the organic geochemical data and the molecular and stable carbon isotopic compositions of natural gas of the Lower Permian Fengcheng Formation in the western Central Depression of Junggar Basin,combined with sedimentary environment analysis and hydrocarbon-generating simulation,the gas-generating potential of the Fengcheng source rock is evaluated,the distribution of large-scale effective source kitchen is described,the genetic types of natural gas are clarified,and four types of favorable exploration targets are selected.The results show that:(1)The Fengcheng Formation is a set of oil-prone source rocks,and the retained liquid hydrocarbon is conducive to late cracking into gas,with characteristics of high gas-generating potential and late accumulation;(2)The maximum thickness of Fengcheng source rock reaches 900 m.The source rock has entered the main gas-generating stage in Penyijingxi and Shawan sags,and the area with gas-generating intensity greater than 20×10^(8) m^(3)/km^(2) is approximately 6500 km^(2).(3)Around the western Central Depression,highly mature oil-type gas with light carbon isotope composition was identified to be derived from the Fengcheng source rocks mainly,while the rest was coal-derived gas from the Carboniferous source rock;(4)Four types of favorable exploration targets with exploration potential were developed in the western Central Depression which are structural traps neighboring to the source,stratigraphic traps neighboring to the source,shale-gas type within the source,and structural traps within the source.Great attention should be paid to these targets. 展开更多
关键词 Junggar Basin western Central Depression Lower Permian Fengcheng Formation gas-generating potential gas-source correlation exploration target
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Detection and characteristics analysis of the western subarctic front using the high-resolution SST product
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作者 Changyuan Chen Chen Wang +4 位作者 Huimin Li Denghui Hu Gang Li Xin Chen Yijun He 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第6期24-32,共9页
Oceanic front plays a significant role in the ocean vertical mixing and the regulation of air-sea interaction,among others.The western branch of the subarctic front(WSAF)located in the Northwest Pacific has attained l... Oceanic front plays a significant role in the ocean vertical mixing and the regulation of air-sea interaction,among others.The western branch of the subarctic front(WSAF)located in the Northwest Pacific has attained lots of attention given its strong intensity and widespread influence on this region.In this study,we take advantage of the merged sea surface temperature(SST)at a high spatial resolution of 0.05°to investigate the characteristics of WSAF.The front detection algorithm that combines the Sobel operator and histogram analysis is adopted.It is advantageous in both preserving the front intensity represented by the SST gradient as well as reducing the detection noise level.We systematically applied this algorithm to the daily SST products for front detection,based on which the WSAF characteristics including its intensity,occurrence of frequency,latitudinal position and coverage area are then extracted.WSAF is mostly located within a small latitude range between 40°N and 41°N with a clear seasonal trend in its intensity that peaks in the winter and troughs in the summer.The seasonal variation of WSAF intensity is almost consistent throughout the temporal period of interest from 2010 to 2018.Similar seasonality is observed for its occurrence of frequency with the winter-summer contrast reaching up to5%.The findings presented here shall help better interpret the WSAF characteristics in the long-term run as well as their impact on the regional weather and climate patterns at high spatial resolution. 展开更多
关键词 sea surface temperature western subarctic front front detection characteristics analysis
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A Middle Pleistocene Glaciation Record from Lacustrine Sediments in the Western Tibetan Plateau and Discussion on Climate Change
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作者 ZHAO Zhenming JI Wenhua FU Chaofeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期623-635,共13页
The Tibetan Plateau is an important area for studying global climate change,but the answers to many scientific problems remain unknown.Here,we present new information from the lacustrine sedimentary record in the west... The Tibetan Plateau is an important area for studying global climate change,but the answers to many scientific problems remain unknown.Here,we present new information from the lacustrine sedimentary record in the western Tibetan Plateau,related to the third most-recent glaciations.Continuous sediment data,including sporopollen,particle size,total organic carbon,mass susceptibility,CaCO_(3),CaSO_(4),BaSO_(4)contents and chronological data,were reconstructed and revealed that climate and environmental conditions obviously and distinctly changed between 600 and 700 thousand years ago.In comparison,the data obtained from the Guliya ice core in this area also corresponds to the global glacial climatic characteristics recorded in basin sediments in the eastern and southeastern regions of the plateau and to the information obtained from ice cores in the Antarctic and Arctic regions.In this study,we conclude that the main reason for the glaciations and new tectonic movement must be a geomagnetic polarity reversal 774 thousand years ago(from Matuyama to Brunhes).Indeed,the results of this study suggest that the described reversal event might have influenced the current global climate pattern and will continue to impact climatic changes in the future. 展开更多
关键词 glacial record global climate change geomagnetic polarity reversal middle Pleistocene western Tibetan Plateau
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Fuzzy cluster analysis of water mass in the western Taiwan Strait in spring 2019
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作者 Zhiyuan Hu Jia Zhu +4 位作者 Longqi Yang Zhenyu Sun Xin Guo Zhaozhang Chen Linfeng Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第12期1-8,共8页
The classification of the springtime water mass has an important influence on the hydrography,regional climate change and fishery in the Taiwan Strait.Based on 58 stations of CTD profiling data collected in the wester... The classification of the springtime water mass has an important influence on the hydrography,regional climate change and fishery in the Taiwan Strait.Based on 58 stations of CTD profiling data collected in the western and southwestern Taiwan Strait during the spring cruise of 2019,we analyze the spatial distributions of temperature(T)and salinity(S)in the investigation area.Then by using the fuzzy cluster method combined with the T-S similarity number,we classify the investigation area into 5 water masses:the Minzhe Coastal Water(MZCW),the Taiwan Strait Mixed Water(TSMW),the South China Sea Surface Water(SCSSW),the South China Sea Subsurface Water(SCSUW)and the Kuroshio Branch Water(KBW).The MZCW appears in the near surface layer along the western coast of Taiwan Strait,showing low-salinity(<32.0)tongues near the Minjiang River Estuary and the Xiamen Bay mouth.The TSMW covers most upper layer of the investigation area.The SCSSW is mainly distributed in the upper layer of the southwestern Taiwan Strait,beneath which is the SCSUW.The KBW is a high temperature(core value of 26.36℃)and high salinity(core value of 34.62)water mass located southeast of the Taiwan Bank and partially in the central Taiwan Strait. 展开更多
关键词 water mass classification western Taiwan Strait fuzzy cluster analysis T-S similarity number
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Research on the Industrial Transfer and Restructuring Path of the Energy-Intensive Manufacturing Industry in Western China
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作者 Wang Fang Chen Shiwei Qu Tiantian 《Contemporary Social Sciences》 2023年第2期21-37,共17页
The orderly transfer of the manufacturing industry is a major action in China’s industrial restructuring.From the perspective of industrial transfer,we used the concentration ratio to depict the trend of the industri... The orderly transfer of the manufacturing industry is a major action in China’s industrial restructuring.From the perspective of industrial transfer,we used the concentration ratio to depict the trend of the industrial transfer of energy-intensive manufacturing in the eastern,central,and western regions since the policy of large-scale development of western China was implemented.We measured the total factor productivity(TFP)of western China using the DEAMalmquist index method.We conducted a regression analysis to measure the effect of western China’s undertaking of the transfer of the energy-intensive manufacturing industry.The findings of this study show that during 2000–2019,eleven provinces(as well as autonomous regions and municipalities)in western China undertook the transfer of the energy-intensive manufacturing industry from the eastern and central regions to varying degrees,exhibiting significant phase features regarding the rate and scale of transfers.Further investigation also demonstrated that the transfer of energy-intensive manufacturing industries has a U-shaped enabling effect on TFP in western China with the scale effect greater than the technology effect.Therefore,it is necessary to transition from“extensive industrial transfer”at the cost of the labor force,land,and resources to“modern industrial transfer”featured by technology and efficiency improvements to contribute to industrial restructuring in western China effectively. 展开更多
关键词 industrial transfer energy-intensive manufacturing industry western China total factor productivity(TFP) U-shaped relationship
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Survey and Countermeasures on Current Status of Farmer Training and Education Informatization in Western Liaoning Province
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作者 Zeguo DENG Jianwei LIU 《Asian Agricultural Research》 2023年第1期50-57,共8页
This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current st... This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current status of agricultural development in western Liaoning and farmers’needs for education and training and rural education informatization were surveyed.The construction of an education and technical support service platform for scientific and technological farmers in western Liaoning was proposed,aiming to use information technology to train modern professional farmers.Through independent and self-learning education and training methods,it is expected to promote great improvement in the scientific and technological quality and moral level of farmers in western Liaoning and cultivate professional farmers who are educated and understand both agricultural techniques and business management. 展开更多
关键词 western Liaoning Province Professional farmers Education informatization TRAINING
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Nursing perspective of expert consensus for diagnosis and treatment of gastric cancer with integrated traditional Chinese and Western medicine
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作者 Shuhong LIU Ling TANG +4 位作者 Yanan ZHAO Jingjing HUO Yan ZHAO Kang YAN Baoya ZHAO 《Journal of Integrative Nursing》 2023年第1期8-14,共7页
Gastric cancer is a common and highly malignant tumor of the digestive system,which seriously threatens human health.The benefit of surgical treatment is limited.The effect of radiotherapy and chemotherapy is not sign... Gastric cancer is a common and highly malignant tumor of the digestive system,which seriously threatens human health.The benefit of surgical treatment is limited.The effect of radiotherapy and chemotherapy is not significant,and the toxic and side effects are large.Although the diagnosis and treatment modes of molecular targeting and multidisciplinary cooperation have also been further developed and applied,a relatively unified comprehensive treatment standard scheme has not been formed.Traditional Chinese medicine(TCM),as complementary and alternative medicine,has unique advantages in the development of diagnosis and treatment of diseases in China.Therefore,the Chinese Association of Integrative Medicine formed“Expert Consensus for Diagnosis and Treatment of Gastric Cancer with Integrated Traditional Chinese and Western Medicine”on the basis of clinical practice and experience.In this article,the consensus is interpreted from the perspective of nursing,focusing on the pathogenesis,high‑risk factors,characteristic therapies of TCM,and nursing of integrated traditional Chinese and Western medicine for gastric cancer,to provide a reference for front‑line medical personnel in the roots in the future nursing care of gastric cancer. 展开更多
关键词 Consensus interpretation gastric cancer integrated traditional Chinese and western medicine nursing integrative nursing traditional Chinese medicine
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