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Deep Structural Framework and Genetic Analysis of Gold Concentration Areas in the Northwestern Jiaodong Peninsula, China: A New Understanding based on High-Resolution Reflective Seismic Survey 被引量:23
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作者 YU Xuefeng SHAN Wei +8 位作者 XIONG Yuxin GENG Ke SUN Yuqin CHI Naijie GUO Baokui LI Dapeng LI Hongkui SONG Yingxin YANG Deping 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期1823-1840,共18页
The gold concentration areas in the northwestern Jiaodong Peninsula constituted an important gold metallogenetic region in Eastern China during the Mesozoic. The deep geological bodies' texture characteristic is impo... The gold concentration areas in the northwestern Jiaodong Peninsula constituted an important gold metallogenetic region in Eastern China during the Mesozoic. The deep geological bodies' texture characteristic is important for exploring the resources thoroughly and understanding the metallogenic process. The detailed textures were revealed using high-resolution seismic profiles through the three major ore-controlling structures-Sanshandao fault zone, Jiaojia fault zone and Zhaoping fault zone. This study aims to establish a deep structural framework of this area. Based on their formation mechanism, the fault structures developed in the area can be divided into regional and local fault structures. The structural styles are characterised by superimposing their compressional, strike-slip and extensional multi-stage activities. The crust is cut by vertical structures corresponding to a left-lateral strike-slip fault system on the surface. Nearby these structures are the arc-shape structures formed by multi-stage magma intrusions into the upper crust. Bounded by the Tancheng–Lujiang and Muping–Jimo fault zones, the current Jiaodong block, developed a series of NE-trending strike-slip fault systems, was probably formed by the assemblage of several obliquely aligned blocks. The intensive magmatism and hydrothermal activity between the blocks induced large-scale mineralisation. It provides a new angle of view for understanding the cratonic destruction and large ore-concentration formed during the Mesozoic. 展开更多
关键词 ore concentration area deep exploration strike-slip faults Sanshandao fault zone cratonic destruction Shandong
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Deep reinforcement learning and its application in autonomous fitting optimization for attack areas of UCAVs 被引量:12
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作者 LI Yue QIU Xiaohui +1 位作者 LIU Xiaodong XIA Qunli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期734-742,共9页
The ever-changing battlefield environment requires the use of robust and adaptive technologies integrated into a reliable platform. Unmanned combat aerial vehicles(UCAVs) aim to integrate such advanced technologies wh... The ever-changing battlefield environment requires the use of robust and adaptive technologies integrated into a reliable platform. Unmanned combat aerial vehicles(UCAVs) aim to integrate such advanced technologies while increasing the tactical capabilities of combat aircraft. As a research object, common UCAV uses the neural network fitting strategy to obtain values of attack areas. However, this simple strategy cannot cope with complex environmental changes and autonomously optimize decision-making problems. To solve the problem, this paper proposes a new deep deterministic policy gradient(DDPG) strategy based on deep reinforcement learning for the attack area fitting of UCAVs in the future battlefield. Simulation results show that the autonomy and environmental adaptability of UCAVs in the future battlefield will be improved based on the new DDPG algorithm and the training process converges quickly. We can obtain the optimal values of attack areas in real time during the whole flight with the well-trained deep network. 展开更多
关键词 attack area neural network deep deterministic policy gradient(DDPG) unmanned combat aerial vehicle(UCAV)
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Land Remediation Projects in Poverty-stricken Counties in Tibetan Areas Promoting Poverty Alleviation——A Case Study of Songpan County,Sichuan Province 被引量:2
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作者 Feng QIU Zisheng YANG 《Asian Agricultural Research》 2019年第3期55-58,61,共5页
Songpan County is a poverty-stricken county in the four provinces of China,one of the concentrated areas in China. This paper analyzes the effectiveness of land consolidation in Songpan County to promote poverty allev... Songpan County is a poverty-stricken county in the four provinces of China,one of the concentrated areas in China. This paper analyzes the effectiveness of land consolidation in Songpan County to promote poverty alleviation and development through specific cases. The results show that land remediation has improved agricultural production conditions,promoted agricultural efficiency,increased farmers' income,improved rural living conditions,promoted the development of urban and rural integration,improved the ecological environment,solved the problem that restricts the survival and development of poverty-stricken areas,enhanced the ability of farmers to develop themselves,raised the level of civilization in rural areas,and promoted poverty alleviation and development. The poverty alleviation and development has provided certain financial support for land remediation. It has promoted land remediation,and pointed out key directions for land remediation. It has an indirect promotion effect on land remediation. 展开更多
关键词 LAND REMEDIATION POVERTY alleviation poverty-stricken areas TIBETAN areas Songpan County
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Empirical Analysis of Factors Influencing Surplus Labor Transfer in Poverty-stricken Areas: A Case Study of Yimatu Town in Fuxin City 被引量:2
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作者 CHEN Shuang 1 ,ZHANG Yan2,HU Li-jia1 1.Southwest Forestry University,Kunming 650224,China 2.Shenyang Agricultural University,Shenyang 110866,China 《Asian Agricultural Research》 2012年第7期53-57,共5页
From the microscopic point of view,taking the surplus labor transfer in the Yimatu Town area as study object,we conduct survey of characteristics and transfer of rural surplus labor in Yimatu Town,through questionnair... From the microscopic point of view,taking the surplus labor transfer in the Yimatu Town area as study object,we conduct survey of characteristics and transfer of rural surplus labor in Yimatu Town,through questionnaires and field interviews.Then we analyze the main factors influencing surplus labor transfer in rural areas from the personal characteristics of labor forces and family factor of labor forces.The results show that gender,age,educational level,farmland management days and other factors pertaining to the labor forces all affect the transfer of surplus labor, but the size and extent of the impact vary.In accordance with various influencing factors,we put forward recommendations for promoting the effective transfer of surplus labor in rural areas as follows:first,paying equal attention to macroscopic factors and microscopic factors influencing the transfer of surplus labor;second,focusing on the factors concerning the rural households and individual farmers,to find out the factors influencing the rational transfer;third,shifting the employment concept of surplus labor in rural areas;fourth,speeding up the construction of small towns and developing the secondary and tertiary industries. 展开更多
关键词 Yimatu TOWN poverty-stricken areas SURPLUS LABOR T
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Realization Path for Inclusive Finance to Support Rural Revitalization in Poverty-stricken Areas 被引量:1
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作者 Qi HUANG 《Asian Agricultural Research》 2021年第6期1-5,共5页
Based on the quarterly economic,social and financial development data of 39 poverty-stricken counties in Henan Province during 2016-2018,this paper utilized the entropy-based TOPSIS method to objectively measure the r... Based on the quarterly economic,social and financial development data of 39 poverty-stricken counties in Henan Province during 2016-2018,this paper utilized the entropy-based TOPSIS method to objectively measure the rural revitalization index,and then built the quantile regression model to study the effects of various elements of inclusive finance on different stages of rural revitalization.Research results show that industrial development,agricultural modernization,targeted poverty alleviation,endogenous demand,and rural governance are the main points of inclusive finance in poverty-stricken areas to support rural revitalization;the rural revitalization index indicates that compared with the Dabie Mountain area and the non-contiguous poverty-stricken areas,the rural revitalization of the Qinba Mountain area is slower;for inclusive finance supporting rural revitalization,it is necessary to bring into play the role of monetary policy tools in re-lending,functions of credit in supporting industrial development,and role of insurance in risk protection;furthermore,inclusive finance solves problems such as the diminishing marginal effect of physical machinery investment in rural revitalization support,financial support for the coordinated development of small farmers and new agricultural business entities,financial support for the development of the entire industry chain,and the"siphon effect"of capital. 展开更多
关键词 Inclusive finance Rural revitalization poverty-stricken areas Entropy-based TOPSIS Quantile regression analysis method
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Deep Learning-Based ECG Classification for Arterial Fibrillation Detection
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作者 Muhammad Sohail Irshad Tehreem Masood +3 位作者 Arfan Jaffar Muhammad Rashid Sheeraz Akram Abeer Aljohani 《Computers, Materials & Continua》 SCIE EI 2024年第6期4805-4824,共20页
The application of deep learning techniques in the medical field,specifically for Atrial Fibrillation(AFib)detection through Electrocardiogram(ECG)signals,has witnessed significant interest.Accurate and timely diagnos... The application of deep learning techniques in the medical field,specifically for Atrial Fibrillation(AFib)detection through Electrocardiogram(ECG)signals,has witnessed significant interest.Accurate and timely diagnosis increases the patient’s chances of recovery.However,issues like overfitting and inconsistent accuracy across datasets remain challenges.In a quest to address these challenges,a study presents two prominent deep learning architectures,ResNet-50 and DenseNet-121,to evaluate their effectiveness in AFib detection.The aim was to create a robust detection mechanism that consistently performs well.Metrics such as loss,accuracy,precision,sensitivity,and Area Under the Curve(AUC)were utilized for evaluation.The findings revealed that ResNet-50 surpassed DenseNet-121 in all evaluated categories.It demonstrated lower loss rate 0.0315 and 0.0305 superior accuracy of 98.77%and 98.88%,precision of 98.78%and 98.89%and sensitivity of 98.76%and 98.86%for training and validation,hinting at its advanced capability for AFib detection.These insights offer a substantial contribution to the existing literature on deep learning applications for AFib detection from ECG signals.The comparative performance data assists future researchers in selecting suitable deep-learning architectures for AFib detection.Moreover,the outcomes of this study are anticipated to stimulate the development of more advanced and efficient ECG-based AFib detection methodologies,for more accurate and early detection of AFib,thereby fostering improved patient care and outcomes. 展开更多
关键词 Convolution neural network atrial fibrillation area under curve ECG false positive rate deep learning CLASSIFICATION
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Analysis on Temporal and Spatial Changes and Driving Forces of Poverty-Stricken Areas in Hebei Province
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作者 Shi Xiaoli, Yuan Jinguo & Wang WeiCollege of Resources and Environmental Sciences, Hebei Normal University, Shijiazhuang 050016,China 《Chinese Journal of Population,Resources and Environment》 北大核心 2005年第2期42-48,共7页
关键词 poverty-stricken areas temporal andspatial changes Hebei Province driving forces
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Multi-level Cooperation and Complementary Advantage Poverty Alleviation Model in Poverty-Stricken Counties of Tibetan Areas:A Case Study of Songpan County in Sichuan Province
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作者 Feng QIU Zisheng YANG +1 位作者 Kai RAO Qiude LI 《Asian Agricultural Research》 2019年第10期66-75,共10页
Songpan County is a poverty-stricken county in Tibetan areas of Sichuan Province,it belongs to a concentrated poverty-stricken area in China.Through summarizing the specific conditions of multi-level cooperation and c... Songpan County is a poverty-stricken county in Tibetan areas of Sichuan Province,it belongs to a concentrated poverty-stricken area in China.Through summarizing the specific conditions of multi-level cooperation and complementary advantage poverty alleviation model in Songpan County,this paper analyzed the effect of this model.Through the analysis on the cooperative poverty alleviation model(eastern-western cooperation,provincial targeted assistance,county-wide"four-leading and four-assistance"inner-party assistance,social force"10000 enterprises helping 10000 villages",and"visiting every household and keeping every person busy"),it summarized the implementation and actual results of each level.In addition,it summarized the problems encountered in the implementation process of multi-level cooperation and complementary advantage poverty alleviation model and came up with recommendations.With the aid of this successful multi-level cooperation and complementary advantage poverty alleviation model,Songpan County has achieved a decisive victory in the fight against poverty.At the end of April 2019,the poverty rate in the whole region fell to 0.45%,and it successfully took off the poverty hat.This paper analyzed and refined the specific practice,main achievements,successful experience,implications and reference significance of multi-level cooperation and complementary advantage poverty alleviation model,to provide necessary references for innovation of poverty alleviation model in poverty-stricken Tibetan areas,or even other similar provinces and regions. 展开更多
关键词 MULTI-LEVEL COOPERATION POVERTY alleviation ACHIEVEMENTS poverty-stricken COUNTY in Tibetan areas Songpan COUNTY
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Poverty Alleviation through Employment Promotion in Extreme Poverty-stricken Areas in Western China: A Case Study of Targeted Poverty Alleviation through Employment Promotion in Awang Town,Dongchuan District
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作者 Yi LOU Zisheng YANG 《Asian Agricultural Research》 2019年第7期55-62,共8页
Poverty alleviation through employment promotion is to promote the poor households to get rid of poverty through promoting employment to increase income. It is the most effective and direct way out of poverty. Dongchu... Poverty alleviation through employment promotion is to promote the poor households to get rid of poverty through promoting employment to increase income. It is the most effective and direct way out of poverty. Dongchuan District, located in the alpine valley area of northeastern Yunnan, is a typical extreme poverty-stricken county in China. Under its jurisdiction, Awang Town is a mountainous township with a wide area of poverty and an extreme poverty. The incidence of poverty in 2015 reached 35.39%. In recent years, through the implementation of various policies to combat poverty, combined with the advantages as a traditional "hometown of migrant labor", focusing on employment- promoting poverty alleviation work, Awang Town has made certain achievements in poverty alleviation work. By the end of 2018, the poverty rate in the town fell to 0.57%, marking a major victory in the town s fight against poverty. Through field investigations, this article summarizes the main practices of Awang Town to carry out employment-promoting targeted poverty alleviation, analyzes the poverty alleviation achievements and successful experience of the town s employment-promoting targeted poverty alleviation work and discusses the promotion and application of this model so as to provide reference Yunnan Province and other poverty-stricken areas to carry out employment-promoting poverty alleviation. 展开更多
关键词 EXTREME poverty-stricken areas POVERTY alleviation though employment promotion Model POVERTY alleviation achievements Awang TOWN Dongchuan District
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From anti-poverty to revitalization: Exploring the path of sustainable development in poverty-stricken areas
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作者 YANG Yong LI Shi-ran 《Ecological Economy》 2019年第1期66-74,共9页
On the basis of analyzing the internal logic of rural revitalization and targeted poverty alleviation, it has made a path analysis of the decision-making to overcome poverty and effectively strengthen the rural revita... On the basis of analyzing the internal logic of rural revitalization and targeted poverty alleviation, it has made a path analysis of the decision-making to overcome poverty and effectively strengthen the rural revitalization. Grasping the internal unity of Marxism and the socialist theory system with Chinese characteristics, profoundly expounding the 'comprehensive' rural revitalization and 'concentration'targeted poverty alleviation, 'long-term' rural revitalization and 'stage' targeted poverty alleviation, and'active' rural revitalization Corresponding to the 'passive' targeted poverty alleviation, it corresponds to the philosophical logic of the materialist dialectic, the law of the unity of opposites, the law of mutual change of quality, and the law of negation of negation. It points out the path of targeted poverty alleviation work under the rural revitalization strategy: scientifically compiling the functional spatial planning of poor rural areas;party building leads the transformation of concepts;industrial development is expanding in depth;and public services are advancing to market. 展开更多
关键词 rural REVITALIZATION TARGETED POVERTY alleviation poverty-stricken areas path selection
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New perspective of Miocene marine hydrocarbon source rocks in deep-water area in Qiongdongnan Basin of northern South China Sea 被引量:3
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作者 LI Wenhao ZHANG Zhihuan +1 位作者 LI Youchuan FU Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第5期107-114,共8页
Drilling wells reveal that the organic matter abundance of Miocene marine source rocks in shallow water area of the Qiongdongnan Basin is relatively low with poor hydrocarbon generation poten- tial. However, in some d... Drilling wells reveal that the organic matter abundance of Miocene marine source rocks in shallow water area of the Qiongdongnan Basin is relatively low with poor hydrocarbon generation poten- tial. However, in some drilling wells of deep water area close to the central depression belt, Miocene marine source rocks with better organic matter abundance and hydrocarbon generation have been found, which have achieved better source rock standard based on the analysis of geochemical charac- teristics. Although there are no exploratory wells in deep water area of the research region, through the comparative analysis of geochemical data of several typical exploratory wells respectively from shallow water area in the basin, central depression belt margin in deep-water area of the basin and Site 1148 of deep sea drilling in the South China Sea Basin, it reveals that the tendency of the quality of source rocks becomes positive gradually from delta to bathyal environment, which then becomes negative as in deep oceanic environment. Owing to the lack of terrestrial organic matter input, the important controlling factors of Miocene marine source rocks in the Qiongdongnan Basin are ocean productivity and preservation conditions of organic matter. The element geochemistry data indicate that the tendency of the paleoproductivity and the preservation conditions of organic matter become positive as water depth increase from shallow area to bathyal area close to central depression belt. So it is speculated that there must exist high quality source rocks in the central depression area where the preservation conditions of organic matter are much better. Besides, in theory, in oxygen-poor zone of oceanic environment at the water depth 400–1 000 m, the preservation conditions of organic matter are well thus forming high-quality marine source rocks. The result- ing speculation, it is reasonable to consider that there are high hydrocarbon generation potential source rocks in bathyal environment of the Qiongdongnan Basin, especially at the water depth 400– 1 000 m. 展开更多
关键词 hydrocarbon-generation potential marine source rocks ocean productivity preserva- tion condition deep water area deep sea drilling
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Impacts of formal credit on rural household income:Evidence from deprived areas in western China 被引量:5
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作者 CHEN Si LUO Er-ga +2 位作者 Lita ALITA HAN Xiao NIE Feng-ying 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第4期927-942,共16页
Financial support is a crucial part of China's poverty alleviation effort.Thus,it is vital to understand how formal credit impacts income growth in rural households.In 2012,2015,and 2018,a survey was conducted to ... Financial support is a crucial part of China's poverty alleviation effort.Thus,it is vital to understand how formal credit impacts income growth in rural households.In 2012,2015,and 2018,a survey was conducted to obtain a panel dataset of 592 rural households from 6 poverty-stricken counties in western China,including counties in Guizhou,Yunnan,and Shaanxi provinces.We use the data to examine the effect of formal credit on rural household income and the mechanism that underlies this effect.We find that formal credit can significantly increase rural households'income in deprived areas in western China.Furthermore,formal credit promotes the reallocation of household labor from the agricultural sector to the non-agricultural sector and changes rural households'decisions about investment-consumption behavior.These are the drivers of changes in the amount and structure of household income.Further analyses show that formal credit may widen income inequality among rural households in western China's deprived areas.The individual characteristics of rural households,such as different levels of material capital,human capital,and social capital,bring about differences in the effects of formal credit on income growth.This study emphasizes that the implementation of formal credit is an essential strategy for poverty alleviation in underdeveloped areas,but policymakers should not excessively interfere with the financial market. 展开更多
关键词 formal credit rural household income rural finance poverty-stricken areas in western China
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Chemical kinetics evaluation and its application of natural gas generation derived from the Yacheng Formation in the deep-water area of the Qiongdongnan Basin,China 被引量:1
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作者 SU Long ZHANG Dongwei +4 位作者 YANG Haizhang CHEN Ying CHEN Guojun ZHENG Jianjing XU Yongchang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第1期50-59,共10页
The natural gas generation process is simulated by heating source rocks of the Yacheng Formation, including the onshore-offshore mudstone and coal with kerogens of Type II2-III in the Qiongdongnan Basin. The aim is to... The natural gas generation process is simulated by heating source rocks of the Yacheng Formation, including the onshore-offshore mudstone and coal with kerogens of Type II2-III in the Qiongdongnan Basin. The aim is to quantify the natural gas generation from the Yacheng Formation and to evaluate the geological prediction and kinetic parameters using an optimization procedure based on the basin modeling of the shallow-water area. For this, the hydrocarbons produced have been grouped into four classes(C1, C2, C3 and C4-6). The results show that the onset temperature of methane generation is predicted to occur at 110℃ during the thermal history of sediments since 5.3 Ma by using data extrapolation. The hydrocarbon potential for ethane, propane and heavy gaseous hydrocarbons(C4-6) is found to be almost exhausted at geological temperature of 200℃ when the transformation ratio(TR) is over 0.8, but for which methane is determined to be about 0.5 in the shallow-water area. In contrast, the end temperature of the methane generation in the deep-water area was over 300℃ with a TR over 0.8. It plays an important role in the natural gas exploration of the deep-water basin and other basins in the broad ocean areas of China. Therefore, the natural gas exploration for the deep-water area in the Qiongdongnan Basin shall first aim at the structural traps in the Ledong, Lingshui and Beijiao sags, and in the forward direction of the structure around the sags, and then gradually develop toward the non-structural trap in the deep-water area basin of the broad ocean areas of China. 展开更多
关键词 deep—water area geological prediction natural gas Yacheng Formation EVALUATION Qiongdongnan Basin
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Industrial Poverty Alleviation Model in Deep Poverty-stricken Villages in the Dry-hot Valley of Jinsha River: A Case Study of Poverty Alleviation in the Green Prickleyash Planting Industry in Laopingzi Village,Luquan County 被引量:1
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作者 Meiqi SHAO Zisheng YANG 《Asian Agricultural Research》 2019年第6期59-63,70,共6页
Industrial poverty alleviation is the core of poverty alleviation in rural areas of China,and it is the fundamental way for the rural poor to achieve stable income and poverty alleviation. Laopingzi Village,Jiaopingdu... Industrial poverty alleviation is the core of poverty alleviation in rural areas of China,and it is the fundamental way for the rural poor to achieve stable income and poverty alleviation. Laopingzi Village,Jiaopingdu Town,Luquan County,Kunming County,Yunnan Province,located in the dry-hot valley area of Jinsha River,has become a typical deep poverty-stricken village due to its special natural conditions.In recent years,in the battle to win the fight against poverty,the people of Laopingzi Village have achieved a virtuous cycle of the ecological environment and an access to get rid of poverty and get rich through vigorously developing green prickleyash planting industry. By the end of 2018,the incidence of poverty in Laopingzi Village Committee dropped from 45. 62% in 2014 to 1. 11%,and the green prickleyash planting industry had achieved remarkable results in poverty alleviation. This article summarizes the specific practices of developing the green prickleyash planting industry in the village,analyzes the main results and successful experiences of the mode and discusses the inspiration of the implementation of green prickleyash cultivation on industrial poverty alleviation,so as to provide an effective practical example for the development and poverty alleviation of poverty-stricken areas. 展开更多
关键词 INDUSTRIAL poverty alleviation Green prickleyash Characteristic PLANTING Mode deep poverty-stricken VILLAGE Dry-hot valley area of Jinsha River
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Basic Features of the Crustal Structure in the Lower Yangtze and Its Neighboring Area in the Chinese Mainland: Review of Deep Seismic Sounding Research 被引量:3
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作者 Bai Zhiming Wu Qingju +1 位作者 Xu Tao Wang Xiao 《Earthquake Research in China》 CSCD 2016年第3期298-315,共18页
The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection /... The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection / refraction record sections,and of the crustal structure are summarized. It shows that there were in total five clear wave groups on the record sections,which include the first arrival Pg,the reflection P1 from the bottom interface of the upper crust,the reflection P3 from the bottom interface of the middle crust,the strong reflection Pm from the Moho boundary,and the refraction Pn from uppermost mantle. In general,these phases are easily consistently traced and compared,despite some first arrivals being delayed or arriving earlier than normal due to the shallow sedimentary cover or bedrocks. In particular,in the Dabie Mountain region the seismic events of a few gathered shots always have weak reflection energy,are twisted,or exhibit disorganized waveforms, which could be attributed to the disruption variations of reflection depth,the broken Moho,and the discontinuity of the reflection boundary within crust. The regional crustal structures are composed of the upper,middle and lower crust,of which the middle and lower layers can be divided into two weak reflection ones. The crustal thickness of the North China and Yangtze platform are 30km- 36 km,and the Moho exhibits a flat geometry despite some local uplifts. The average pressure velocity in lower crust beneath this two tectonic area is 6. 7 ± 0. 3km / s. Nevertheless,beneath the Dabieshan area the crustal thickness is 32km- 41 km,the Moho bends down sharply andtakes an abrupt 4km- 7km dislocation in the vertical direction. The average pressure velocity in the lower crust beneath the Dabieshan area is 6. 8 ± 0. 2km / s. 展开更多
关键词 deep seismic sounding projects Wave group feature Crustal structure feature Anhui Province and its neighboring area
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Gravity inversion of deep-crust and mantle interfaces in the Three Gorges area 被引量:1
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作者 Wang Jian Shen Chongyang +2 位作者 Li Hui Sun Shaoan Xing Lelin 《Geodesy and Geodynamics》 2012年第4期7-17,共11页
To better understand the heterogeneity of deep-crust and mantle interfaces in the region of the Three Gorges, China, we used the Parker-Oldenburg iterative inversion method to invert existing Bouguer gravity data from... To better understand the heterogeneity of deep-crust and mantle interfaces in the region of the Three Gorges, China, we used the Parker-Oldenburg iterative inversion method to invert existing Bouguer gravity data from the Three Gorges area ( 1 : 500000) , a new gravity map of the Three Gorges Dam ( 1 : 200000) , and the results of deep seismic soundings. The inversion results show a Moho depth of 42 km be- tween Badong and Zigui and the depth of the B2 lower-crustal interface beneath the Jianghan Plain and sur- rounding areas at 21 -25 km. The morphology of crustal interfaces and the surface geology present an over- pass structure. The mid-crust beneath the Three Gorges Dam is approximately 9 km thick, which is the thin- nest in the Three Gorges area and may be related to the shallow low-density body near the Huangling anti- cline. The upper crust is seismogenic, and there is a close relationship between seismicity and the deep- crust and mantle interfaces. For example, the MS. 1 Zigui earthquake occurred where the gradients of the Moho and the B2 interface are the steepest, showing that deep structure has a very important effect on re- gional seismicity. 展开更多
关键词 INVERSION gravity anomaly deep structure the Three Gorges area
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Crustal Electrical Structure and Deep Metallogenic Potential in Northern Wuyi Area(South China),based on Magnetotelluric Data 被引量:1
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作者 LUO Fan Lü Qingtian +4 位作者 ZHANG Kun YAN Jiayong Colin GFARQUHARSON ZHANG Chong FU Guangming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第3期791-805,共15页
The northern Wuyi area,which is located in the northern Wuyi metallogenic belt,has superior mineralization conditions.The Pingxiang-Guangfeng-Jiangshan-Shaoxing fault(PSF)extends across the whole region regardless of ... The northern Wuyi area,which is located in the northern Wuyi metallogenic belt,has superior mineralization conditions.The Pingxiang-Guangfeng-Jiangshan-Shaoxing fault(PSF)extends across the whole region regardless of whether or how the PSF relates to the near-surface mineralization.We carried out an MT survey in the region and obtained a reliable 2D model of the crustal electrical structure to a depth of 30 km.In the resistivity model,we inferred that a continuous high conductivity belt that ranges from the shallow to deep crust is a part of the PSF.Then,we estimated the fluid content and pressure gradient to identify the deep sources of fluid as well as its pattern of motion pattern.Finally,we proposed a model for the deep metallogenic migration processes that combines geological data,fluid content data,pressure gradient data,and the subsurface resistivity model.The model analysis showed that the Jiangnan orogenic belt and the Cathaysia block formed the PSF during the process of com.The deep fluid migrated upward through the PSF to the shallow crust.Therefore,we believe that the PSF is an ore-forming fluid migration channel and that it laid the material basis for large-scale mineralization in the shallow crust. 展开更多
关键词 MAGNETOTELLURICS crustal electrical structure PSF deep metallogenic background model northern Wuyi area
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Predicting the 25th solar cycle using deep learning methods based on sunspot area data 被引量:1
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作者 Qiang Li Miao Wan +2 位作者 Shu-Guang Zeng Sheng Zheng Lin-Hua Deng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第7期290-298,共9页
It is a significant task to predict the solar activity for space weather and solar physics. All kinds of approaches have been used to forecast solar activities, and they have been applied to many areas such as the sol... It is a significant task to predict the solar activity for space weather and solar physics. All kinds of approaches have been used to forecast solar activities, and they have been applied to many areas such as the solar dynamo of simulation and space mission planning. In this paper, we employ the long-shortterm memory(LSTM) and neural network autoregression(NNAR) deep learning methods to predict the upcoming 25 th solar cycle using the sunspot area(SSA) data during the period of May 1874 to December2020. Our results show that the 25 th solar cycle will be 55% stronger than Solar Cycle 24 with a maximum sunspot area of 3115±401 and the cycle reaching its peak in October 2022 by using the LSTM method. It also shows that deep learning algorithms perform better than the other commonly used methods and have high application value. 展开更多
关键词 Sun:activity Sun:solar cycle prediction Sun:sunspot area Method:deep neural network
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The Relationship between Tectonic Subsidence and BSR of Upper Neogene in the Deep-Water Area of the Northern Continental Slope, South China Sea 被引量:6
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作者 YU Xinghe WANG Jianzhong +5 位作者 LI Shengli FANG Jingnan JIANG Longyan CONG Xiaorong LIANG Jinqiang SHA Zhibin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第3期804-818,共15页
BSR (Bottom Simulating Reflector) occurs widely in the strata since the late Miocene in the deep-water area of the northern continental slope of South China Sea (SCS). It is an important seismic reference mark whi... BSR (Bottom Simulating Reflector) occurs widely in the strata since the late Miocene in the deep-water area of the northern continental slope of South China Sea (SCS). It is an important seismic reference mark which identifies the gas hydrate and its distribution influenced by the tectonic movements. Single-point basin modeling was conducted using 473 points in the study area. To discuss the relationships between the tectonic subsidence and BSR, the volume and rate of tectonic subsidence in each geological time have been simulated. The results show that there are three tectonic accelerate subsidence processes in the study area since the late Miocene, especially since 1.8Ma the tectonic subsidence accelerates more apparently. Since the Late Miocene to Pleistocene, the rate of tectonic subsidence in deep-water underwent a transformation from weak to strong. The ratio of tectonic subsidence to the total subsidence was relatively high (65-70%). Through the superposition of the BSR developed areas and the contours of tectonic subsidence in this area, it was discovered that more than 80% of BSR tend to be distributed at the slope break or depression-uplift structural transfer zone and the average tectonic subsidence rate ranges from 70 m/Ma to 125 m/Ma. 展开更多
关键词 BSR tectonic subsidence quantitative simulation deep-water area Northern continental slope of South China Sea
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Movement characteristics of Karst water in a deep mining area 被引量:2
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作者 CHAO Chen-ming BAI Hai-bo +1 位作者 MIAO Xie-xing YAO Bang-hua 《Mining Science and Technology》 EI CAS 2009年第1期14-18,共5页
In order to study the movement characteristics of groundwater in a deep mining area and solve the dispute of the distri- bution rule of hydro-chemical zoning which is contradicted by lixiviation water zoning in a hori... In order to study the movement characteristics of groundwater in a deep mining area and solve the dispute of the distri- bution rule of hydro-chemical zoning which is contradicted by lixiviation water zoning in a horizontal direction, we directed our attention to the source of deep groundwater, its seepage and hydro-chemical characteristics in a typical mining area. We used a neotectonic water-control theory, chemical and isotope methods, as well as a method for analyzing dynamic groundwater conditions. The results indicate that 1) Karst water in the deep and medium parts of this mining area is recharged by vertical leakage through neotectonic fractures rather than seepage along strata from subcrop parts or surrounding flows; 2) from surface to deep leakage paths, the variation in the types of chemical groundwater agrees with the normal lixiviation water distribution rule and the age of mixed groundwater increases; 3) the water-rich zones along neotectonic fractures correspond with water-diluted zones in a hori-zontal direction; 4) the leakage coefficient and water capacity of aquifers increases during the flow process of Karst water along the antidip direction (from west to east) and 5) Karst water in shallow mining areas forms a strong runoff belt along strikes and quickly dilutes the water from deep and medium mining areas. Overall, chemical and dynamic water characteristics actually agree with in terms of the entire consideration for differences in vertical leakage and abnormalities in the zone of water chemical distribution, along a horizontal runoff direction. 展开更多
关键词 深矿地区 喀斯特水 垂直渗漏量 稀释
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