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Machine learning applications in healthcare clinical practice and research
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作者 Nikolaos-Achilleas Arkoudis Stavros P Papadakos 《World Journal of Clinical Cases》 SCIE 2025年第1期16-21,共6页
Machine learning(ML)is a type of artificial intelligence that assists computers in the acquisition of knowledge through data analysis,thus creating machines that can complete tasks otherwise requiring human intelligen... Machine learning(ML)is a type of artificial intelligence that assists computers in the acquisition of knowledge through data analysis,thus creating machines that can complete tasks otherwise requiring human intelligence.Among its various applications,it has proven groundbreaking in healthcare as well,both in clinical practice and research.In this editorial,we succinctly introduce ML applications and present a study,featured in the latest issue of the World Journal of Clinical Cases.The authors of this study conducted an analysis using both multiple linear regression(MLR)and ML methods to investigate the significant factors that may impact the estimated glomerular filtration rate in healthy women with and without non-alcoholic fatty liver disease(NAFLD).Their results implicated age as the most important determining factor in both groups,followed by lactic dehydrogenase,uric acid,forced expiratory volume in one second,and albumin.In addition,for the NAFLD-group,the 5th and 6th most important impact factors were thyroid-stimulating hormone and systolic blood pressure,as compared to plasma calcium and body fat for the NAFLD+group.However,the study's distinctive contribution lies in its adoption of ML methodologies,showcasing their superiority over traditional statistical approaches(herein MLR),thereby highlighting the potential of ML to represent an invaluable advanced adjunct tool in clinical practice and research. 展开更多
关键词 Machine Learning Artificial INTELLIGENCE CLINICAL Practice research Glomerular filtration rate Non-alcoholic fatty liver disease MEDICINE
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Synthetic data as an investigative tool in hypertension and renal diseases research
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作者 Aleena Jamal Som Singh Fawad Qureshi 《World Journal of Methodology》 2025年第1期9-13,共5页
There is a growing body of clinical research on the utility of synthetic data derivatives,an emerging research tool in medicine.In nephrology,clinicians can use machine learning and artificial intelligence as powerful... There is a growing body of clinical research on the utility of synthetic data derivatives,an emerging research tool in medicine.In nephrology,clinicians can use machine learning and artificial intelligence as powerful aids in their clinical decision-making while also preserving patient privacy.This is especially important given the epidemiology of chronic kidney disease,renal oncology,and hypertension worldwide.However,there remains a need to create a framework for guidance regarding how to better utilize synthetic data as a practical application in this research. 展开更多
关键词 Synthetic data Artificial intelligence NEPHROLOGY Blood pressure research EDITORIAL
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Exploration and Research on the Development of Higher Vocational English Education in Guangxi
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作者 Binbin Liu 《Journal of Contemporary Educational Research》 2024年第10期253-262,共10页
With the acceleration of economic development and globalization and the rapid development of China’s foreign economy,the position of English education in higher vocational education has become increasingly prominent.... With the acceleration of economic development and globalization and the rapid development of China’s foreign economy,the position of English education in higher vocational education has become increasingly prominent.Particularly in the multi-ethnic and multi-cultural areas of Guangxi Zhuang Autonomous Region,higher vocational education undertakes the responsibility of talent export for the construction of the China-ASEAN foreign trade exchange platform.However,the current phenomena and problems existing in higher vocational English education in Guangxi need to be deeply discussed and solved.Therefore,this paper discusses the development ideas of English education mode in Guangxi higher vocational education and studies the feasibility suggestions,in order to provide a reference for the future development of higher vocational English education in Guangxi. 展开更多
关键词 Guangxi higher vocational English Educational development exploration and research
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Research and exploration of direct current power supply and distribution systems for Antarctic research stations
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作者 WANG Lei 《Advances in Polar Science》 CSCD 2024年第2期228-237,共10页
The power supply and distribution systems for Antarctic research stations have special characteristics.In light of a worldwide trend toward a gradual increase in the application of renewable energy,an analysis was per... The power supply and distribution systems for Antarctic research stations have special characteristics.In light of a worldwide trend toward a gradual increase in the application of renewable energy,an analysis was performed to assess the feasibility of achieving a direct current power supply and distribution at Antarctic research stations by comparing the characteristics of direct current and alternating current electricity.Research was also performed on the status quo and future trends in direct current power supply and distribution systems in Antarctica research stations in combination with case studies. 展开更多
关键词 direct current alternating current renewable energy ANTARCTIC research station
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Research funding and citations in papers of Nobel Laureates in Physics, Chemistry and Medicine, 2019-2020 被引量:1
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作者 Mario Coccia Saeed Roshani 《Journal of Data and Information Science》 CSCD 2024年第2期56-80,共25页
Purpose:The goal of this study is a comparative analysis of the relation between funding(a main driver for scientific research)and citations in papers of Nobel Laureates in physics,chemistry and medicine over 2019-202... Purpose:The goal of this study is a comparative analysis of the relation between funding(a main driver for scientific research)and citations in papers of Nobel Laureates in physics,chemistry and medicine over 2019-2020 and the same relation in these research fields as a whole.Design/methodology/approach:This study utilizes a power law model to explore the relationship between research funding and citations of related papers.The study here analyzes 3,539 recorded documents by Nobel Laureates in physics,chemistry and medicine and a broader dataset of 183,016 documents related to the fields of physics,medicine,and chemistry recorded in the Web of Science database.Findings:Results reveal that in chemistry and medicine,funded researches published in papers of Nobel Laureates have higher citations than unfunded studies published in articles;vice versa high citations of Nobel Laureates in physics are for unfunded studies published in papers.Instead,when overall data of publications and citations in physics,chemistry and medicine are analyzed,all papers based on funded researches show higher citations than unfunded ones.Originality/value:Results clarify the driving role of research funding for science diffusion that are systematized in general properties:a)articles concerning funded researches receive more citations than(un)funded studies published in papers of physics,chemistry and medicine sciences,generating a high Matthew effect(a higher growth of citations with the increase in the number of papers);b)research funding increases the citations of articles in fields oriented to applied research(e.g.,chemistry and medicine)more than fields oriented towards basic research(e.g.,physics).Practical implications:The results here explain some characteristics of scientific development and diffusion,highlighting the critical role of research funding in fostering citations and the expansion of scientific knowledge.This finding can support decision-making of policymakers and R&D managers to improve the effectiveness in allocating financial resources in science policies to generate a higher positive scientific and societal impact. 展开更多
关键词 research funding CITATIONS Science diffusion Scientific change Science of Science Power-law distribution Basic research Applied research Matthew effect Nobel Laureates Nobel Prizes
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Geological characteristics and exploration breakthroughs of coal rock gas in Carboniferous Benxi Formation,Ordos Basin,NW China 被引量:2
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作者 ZHAO Zhe XU Wanglin +8 位作者 ZHAO Zhenyu YI Shiwei YANG Wei ZHANG Yueqiao SUN Yuanshi ZHAO Weibo SHI Yunhe ZHANG Chunlin GAO Jianrong 《Petroleum Exploration and Development》 SCIE 2024年第2期262-278,共17页
To explore the geological characteristics and exploration potential of the Carboniferous Benxi Formation coal rock gas in the Ordos Basin,this paper presents a systematic research on the coal rock distribution,coal ro... To explore the geological characteristics and exploration potential of the Carboniferous Benxi Formation coal rock gas in the Ordos Basin,this paper presents a systematic research on the coal rock distribution,coal rock reservoirs,coal rock quality,and coal rock gas features,resources and enrichment.Coal rock gas is a high-quality resource distinct from coalbed methane,and it has unique features in terms of burial depth,gas source,reservoir,gas content,and carbon isotopic composition.The Benxi Formation coal rocks cover an area of 16×104km^(2),with thicknesses ranging from 2 m to 25 m,primarily consisting of bright and semi-bright coals with primitive structures and low volatile and ash contents,indicating a good coal quality.The medium-to-high rank coal rocks have the total organic carbon(TOC)content ranging from 33.49%to 86.11%,averaging75.16%.They have a high degree of thermal evolution(Roof 1.2%-2.8%),and a high gas-generating capacity.They also have high stable carbon isotopic values(δ13C1of-37.6‰to-16‰;δ13C2of-21.7‰to-14.3‰).Deep coal rocks develop matrix pores such as gas bubble pores,organic pores,and inorganic mineral pores,which,together with cleats and fractures,form good reservoir spaces.The coal rock reservoirs exhibit the porosity of 0.54%-10.67%(averaging 5.42%)and the permeability of(0.001-14.600)×10^(-3)μm^(2)(averaging 2.32×10^(-3)μm^(2)).Vertically,there are five types of coal rock gas accumulation and dissipation combinations,among which the coal rock-mudstone gas accumulation combination and the coal rock-limestone gas accumulation combination are the most important,with good sealing conditions and high peak values of total hydrocarbon in gas logging.A model of coal rock gas accumulation has been constructed,which includes widespread distribution of medium-to-high rank coal rocks continually generating gas,matrix pores and cleats/fractures in coal rocks acting as large-scale reservoir spaces,tight cap rocks providing sealing,source-reservoir integration,and five types of efficient enrichment patterns(lateral pinchout complex,lenses,low-amplitude structures,nose-like structures,and lithologically self-sealing).According to the geological characteristics of coal rock gas,the Benxi Formation is divided into 8 plays,and the estimated coal rock gas resources with a buried depth of more than 2000 m are more than 12.33×10^(12)m^(3).The above understandings guide the deployment of risk exploration.Two wells drilled accordingly obtained an industrial gas flow,driving the further deployment of exploratory and appraisal wells.Substantial breakthroughs have been achieved,with the possible reserves over a trillion cubic meters and the proved reserves over a hundred billion cubic meters,which is of great significance for the reserves increase and efficient development of natural gas in China. 展开更多
关键词 coal rock gas coalbed methane medium-to-high rank coal CLEAT Ordos Basin Carboniferous Benxi Formation risk exploration
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A comprehensive review of lunar lava tube base construction and field research on a potential Earth test site 被引量:1
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作者 Yujie Feng Peng-Zhi Pan +3 位作者 Xuhai Tang Zhaofeng Wang Yuxin Li Altaf Hussain 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1201-1216,共16页
The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission... The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission.Lunar lava tubes are special underground caves formed by volcanic eruptions and are considered as ideal natural shelters and scientific laboratories for lunar base construction.This paper begins with an in-depth overview of the geological origins,exploration history,and distribution locations of lunar lava tubes.Subsequently,it delves into the presentation of four distinctive advantages and typical concepts for constructing bases within lava tubes,summarizing the ground-based attempts made thus far in lunar lava tube base construction.Field studies conducted on a lava tube in Hainan revealed rock compositions similar to those found during the Apollo missions and clear lava tube structures,making it a promising analog site.Lastly,the challenges and opportunities encountered in the field of geotechnical engineering regarding the establishment of lunar lava tube bases are discussed,encompassing cave exploration technologies,in-situ testing methods,geomechanical properties under lunar extreme environments,base design and structural stability assessment,excavation and reinforcement techniques,and simulated Earth-based lava tube base. 展开更多
关键词 Lunar lava tube Lunar base construction Extraterrestrial cave exploration Earth analog site
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General laws of funding for scientific citations:how citations change in funded and unfunded research between basic and applied sciences 被引量:1
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作者 Mario Coccia Saeed Roshani 《Journal of Data and Information Science》 CSCD 2024年第4期71-89,共19页
Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relati... Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relationship between research funding and citations of papers using 831,337 documents recorded in the Web of Science database.Findings:The original results reveal general characteristics of the diffusion of science in research fields:a)Funded articles receive higher citations compared to unfunded papers in journals;b)Funded articles exhibit a super-linear growth in citations,surpassing the increase seen in unfunded articles.This finding reveals a higher diffusion of scientific knowledge in funded articles.Moreover,c)funded articles in both basic and applied sciences demonstrate a similar expected change in citations,equivalent to about 1.23%,when the number of funded papers increases by 1%in journals.This result suggests,for the first time,that funding effect of scientific research is an invariant driver,irrespective of the nature of the basic or applied sciences.Originality/value:This evidence suggests empirical laws of funding for scientific citations that explain the importance of robust funding mechanisms for achieving impactful research outcomes in science and society.These findings here also highlight that funding for scientific research is a critical driving force in supporting citations and the dissemination of scientific knowledge in recorded documents in both basic and applied sciences.Practical implications:This comprehensive result provides a holistic view of the relationship between funding and citation performance in science to guide policymakers and R&D managers with science policies by directing funding to research in promoting the scientific development and higher diffusion of results for the progress of human society. 展开更多
关键词 research funding CITATIONS Scientific development Science diffusion Scientific laws Power law model Matthew effect Science policy research policy Science of science Dynamics of science Evolution of science
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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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Research Progress and Prospects of Total Factor Productivity in the Construction Industry 被引量:1
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作者 Chen WANG Shijie YU +2 位作者 Chenhao LIANG Lidan CAI Xiaohong XIONG 《Asian Agricultural Research》 2024年第7期39-41,共3页
The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the ... The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the construction industry to a higher level by scientifically and accurately measuring the total factor productivity of the construction industry and deeply analyzing the influencing factors behind it.Based on a comprehensive consideration of research methods and influencing factors,this paper systematically reviews the existing relevant literature on total factor productivity in the construction industry,aiming to reveal the current research development trend in this field and point out potential problems.This effort aims to provide a solid theoretical foundation and valuable reference for further in-depth research,and jointly promote the continuous progress and development of total factor productivity research in the construction industry. 展开更多
关键词 Construction industry Total factor productivity research progress Influence factor Theoretical basis
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Distribution characteristics, exploration and development, geological theories research progress and exploration directions of shale gas in China 被引量:10
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作者 Shi-zhen Li Zhi Zhou +7 位作者 Hai-kuan Nie Lei-fu Zhang Teng Song Wei-bin Liu Hao-han Li Qiu-chen Xu Si-yu Wei Shu Tao 《China Geology》 2022年第1期110-135,共26页
The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can ... The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can be divided into three types according to their sedimentary environments,namely marine,marine-continental transitional,and continental shales,which are distributed in 13 stratigraphic systems from the Mesoproterozoic to the Cenozoic.The Sichuan Basin and its surrounding areas have the highest geological resources of shale gas,and the commercial development of shale gas has been achieved in the Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in these areas,with a shale gas production of up to 20×10^(9)m^(3) in 2020.China has seen rapid shale gas exploration and development over the last five years,successively achieving breakthroughs and important findings in many areas and strata.The details are as follows.(1)Large-scale development of middle-shallow shale gas(burial depth:less than 3500 m)has been realized,with the productivity having rapidly increased;(2)breakthroughs have been constantly made in the development of deep shale gas(burial depth:3500-4500 m),and the ultradeep shale gas(burial depth:greater than 4500 m)is under testing;(3)breakthroughs have been made in the development of normal-pressure shale gas,and the assessment of the shale gas in complex tectonic areas is being accelerated;(4)shale gas has been frequently discovered in new areas and new strata,exhibiting a great prospect.Based on the exploration and development practice,three aspects of consensus have been gradually reached on the research progress in the geological theories of shale gas achieved in China.(1)in terms of deep-water fine-grained sediments,organic-rich shales are the base for the formation of shale gas;(2)in terms of high-quality reservoirs,the development of micro-nano organic matter-hosted pores serves as the core of shale gas accumulation;(3)in terms of preservation conditions,weak structural transformation,a moderate degree of thermal evolution,and a high pressure coefficient are the key to shale gas enrichment.As a type of important low-carbon fossil energy,shale gas will play an increasingly important role in achieving the strategic goals of peak carbon dioxide emissions and carbon neutrality.Based on the in-depth study of shale gas geological conditions and current exploration progress,three important directions for shale gas exploration in China in the next five years are put forward. 展开更多
关键词 Shale gas Shale gas distribution Formation era Deep-water fine-grained sediments Shale reservoirs Preservation conditions exploration and development Wufeng-Longmaxi formations exploration directions Oil-gas exploration engineering China
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Exploration and research progress of shale gas in China 被引量:25
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作者 Gang-yi Zhai Yu-fang Wang +3 位作者 Zhi Zhou Shu-fang Yu Xiang-lin Chen Yun-xiao Zhang 《China Geology》 2018年第2期257-272,共16页
There are three types of shale gas resources in China.The resources are present in large amounts and are widely distributed.Marine facies,transitional facies and continental facies resources each account for a third.B... There are three types of shale gas resources in China.The resources are present in large amounts and are widely distributed.Marine facies,transitional facies and continental facies resources each account for a third.Based on resource distributions,there are many wells penetrated into the Sinian,Cambrian, Ordovieian,Silurian,Devonian,Carboniferous and Permian strata of the Yangtze plate and its periphery, the North China Craton and the Tarim Basin.Many years of exploration have indicated that the marine Silurian Longmaxi shale gas is widely distributed in south China and has been industrialized in its production in the Siehuan basin.The shale gas from the Cambrian Niutitang Formation and the Sinian Doushantuo Formation are important discoveries in Yichang,Hub ei and Zhenba,Shanxi.There are also shale gas resources found within transitional facies and continental facies in different areas in China.The "two element enrichment theory"has been summarized during the exploration process of Silurian marine shale gas in the Sichuan Basin.In addition,horizontal drilling and fracturing technologies up to 3500 m in depth have been developed.Based on the understanding of shale gas accumulation in a complex tectonic zone outside the Sichnan basin,a preliminary summary of the formation of the "converse fault syneline control reservoir"and "paleo uplift control reservoir"model has been constructed.The dominant theory of "Trinity"shale gas enrichment and the high yield of the "deep water Lu Pengxiang sedimentary facies belt, structural preservation conditions and overpressure"is summarized.Guided by the above theories.Anyel well in Guizhou and Eyangyel well in Hubei were drilled."Four storey"oil and shale "gas is found in the Permian Qixia group,the Silurian Shiniulan Formation,the Longmaxi Formation and the Ordovician Baota Formation in Anyel well.Good shale gas has been gound in the Cambrian Niutitang formation inian Doushantuo formation in Eyangye lwell.This paper aims to summarize and review the main progress,theoretical technology and problems of shale gas exploration and development in recent years in China,and predicts the future exploration and development direction for shale gas and possible exploration areas. 展开更多
关键词 SHALE GAS exploration ENRICHMENT ACCUMULATION THEORETICAL technology
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Two stages power generation test of the hot dry rock exploration and production demonstration project in the Gonghe Basin,northeastern Qinghai-Tibet plateau,China 被引量:1
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作者 Er-yong Zhang Dong-guang Wen +24 位作者 Gui-ling Wang Xian-peng Jin Lin-you Zhang Hai-dong Wu Wen-shi Wang Cheng-ming Ye Wei Weng Kuan Li Jin-sheng Wu Xian-chun Tang Chong-yuan Zhang Qing-da Feng Sheng Lian Li-sha Hu Gui-lin Zhu Xing-long Xie Bin Wu Dan Wang Xue Niu Zhao-xuan Niu Dong-lin Liu Hui Zhang Wen-hao Xu Shu-qing Yao Li Yang 《China Geology》 CAS CSCD 2024年第3期409-421,共13页
The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in eff... The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in efficient drilling and completion,reservoir construction,and fracture simulation.In 2019,China Geological Survey(CGS)initiated a demonstration project of HDR exploration and production in the Gonghe Basin,aiming to overcome the setbacks faced by HDR projects.Over the ensuing four years,the Gonghe HDR project achieved the first power generation in 2021,followed by the second power generation test in 2022.After establishing the primary well group in the initial phase,two directional wells and one branch well were drilled.Noteworthy progress was made in successfully constructing the targeted reservoir,realizing inter-well connectivity,power generation and grid connection,implementing of the real-time micro-seismic monitoring.A closed-loop technical validation of the HDR exploration and production was completed.However,many technical challenges remain in the process of HDR industrialization,such as reservoir fracture network characterization,efficient drilling and completion,multiple fracturing treatment,continuous injection and production,as well as mitigation of induced seismicity and numerical simulation technology. 展开更多
关键词 Power generation Hot dry rock(HDR) Enhanced geothermal system(EGS) Genesis mechanism Gonghe Basin Directional drilling Reservoir construction Circulation test Induced seismicity Clean energy exploration engineering
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Citation distributions and research evaluations:The impossibility of formulating a universal indicator
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作者 Alonso Rodríguez-Navarro 《Journal of Data and Information Science》 CSCD 2024年第4期24-48,共25页
Purpose:To analyze the diversity of citation distributions to publications in different research topics to investigate the accuracy of size-independent,rank-based indicators.The top percentile-based indicators are the... Purpose:To analyze the diversity of citation distributions to publications in different research topics to investigate the accuracy of size-independent,rank-based indicators.The top percentile-based indicators are the most common indicators of this type,and the evaluations of Japan are the most evident misjudgments.Design/methodology/approach:The distributions of citations to publications from countries and journals in several research topics were analyzed along with the corresponding global publications using histograms with logarithmic binning,double rank plots,and normal probability plots of log-transformed numbers of citations.Findings:Size-independent,top percentile-based indicators are accurate when the global ranks of local publications fit a power law,but deviations in the least cited papers are frequent in countries and occur in all journals with high impact factors.In these cases,a single indicator is misleading.Comparisons of the proportions of uncited papers are the best way to predict these deviations.Research limitations:This study is fundamentally analytical,and its results describe mathematical facts that are self-evident.Practical implications:Respectable institutions,such as the OECD,the European Commission,and the U.S.National Science Board,produce research country rankings and individual evaluations using size-independent percentile indicators that are misleading in many countries.These misleading evaluations should be discontinued because they can cause confusion among research policymakers and lead to incorrect research policies.Originality/value:Studies linking the lower tail of citation distribution,including uncited papers,to percentile research indicators have not been performed previously.The present results demonstrate that studies of this type are necessary to find reliable procedures for research assessments. 展开更多
关键词 SCIENTOMETRICS research assessment research indicators Citation distribution Rank analysis
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Notes for the 50th Anniversary Special Issue of Petroleum Exploration and Development
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作者 Zhao Wenzhi 《Petroleum Exploration and Development》 SCIE 2024年第4期F0002-F0002,共1页
The year of 2024 marks the 50th anniversary of the publication of Petroleum Exploration and Development.For half a century,Petroleum Exploration and Development has been committed to disseminating petroleum technology... The year of 2024 marks the 50th anniversary of the publication of Petroleum Exploration and Development.For half a century,Petroleum Exploration and Development has been committed to disseminating petroleum technology,witnessing and recording the glorious journey of China's petroleum industry from being weak to becoming strong.The journal has also become a bright banner in China's petroleum technology industry. 展开更多
关键词 exploration NOTES JOURNAL
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Research and exploration progress on lithium deposits in China 被引量:12
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作者 Deng-hong Wang Hong-zhang Dai +6 位作者 Shan-bao Liu Cheng-hui Wang Yang Yu Jing-jing Dai Li-jun Liu Yue-qing Yang Sheng-chao Ma 《China Geology》 2020年第1期137-152,共16页
Since 2012,some advances have been made through the resource investigation,metallogenesis research,and comprehensive utilizing of lithium deposits in China.Firstly,the progress of lithium exploration has been made in ... Since 2012,some advances have been made through the resource investigation,metallogenesis research,and comprehensive utilizing of lithium deposits in China.Firstly,the progress of lithium exploration has been made in Sichuan,Xinjiang,Qinghai and Jiangxi provinces(autonomous region).Li deposits are not only found within the pegmatite rocks but also within the granitic rocks and sedimentary rocks.Secondly,the methods of geological survey,geochemical and geophysical exploration,remote sensing technology and even drilling technology have been improved,which can be delineating orebodies quickly.Thirdly,the mechanisms of Li mineralization were summarized by analyzing the relationship between the Li contents and kinds of geological phenomena.Based on practice,a new understanding of"multi-cycle,deep circulation,integration of internal and external"metallogenic mechanism or"MDIE"metallogenic mechanism for short has been put forwarded further in this paper,and the"five levels+basement"exploration model has been successfully expanded to guide the prospecting work both in the Jiajika and Keeryin pegmatite ore fields in western Sichuan Province.Besides,new progress has been made in the aspect of amblygonite deposits of granite-type and hydrothermal type in the Mufushan-Jiuling ore district,which points out a new direction for prospecting new types of lithium deposits in China. 展开更多
关键词 Lithium deposits Amblygonite "MDIE"metallogenic mechanism "Five levels+basement"exploration model Mineral exploration engineering China
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Research Advances and Exploration Significance of Large-area Accumulation of Low and Medium Abundance Lithologic Reservoirs 被引量:1
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作者 ZHAO Wenzhi WANG Zecheng WANG Hongjun CHEN Mengjin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期463-476,共14页
In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low... In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low oil/gas column height, multiple thin hydrocarbon layers, and distribution in overlapping and connection, and so on. The advantageous conditions for large-area accumulation of low-medium abundance hydrocarbon reservoirs include: (1) large (fan) delta sandbodies are developed in the hinterland of large flow-uncontrolled lake basins and they are alternated with source rocks extensively in a structure like "sandwiches"; (2) effective hydrocarbon source kitchens are extensively distributed, offering maximum contact chances with various sandbodies and hydrocarbon source rocks; (3) oil and gas columns are low in height, hydrocarbon layers are mainly of normal-low pressure, and requirements for seal rock are low; (4) reservoirs have strong inheterogeneity and gas reservoirs are badly connected; (5) the hydrocarbon desorption and expulsion under uplifting and unloading environments cause widely distributed hydrocarbon source rocks of coal measures to form large-area reservoirs; (6) deep basin areas and synclinal areas possess reservoir-forming dynamics. The areas with great exploration potential include the Paleozoic and Mesozoic in the Ordos Basin, the Xujiahe Formation in Dachuanzhong in the Sichuan basin, deep basin areas in the Songliao basin etc. The core techniques of improving exploration efficiency consist of the sweetspot prediction technique that focuses on fine characterization of reservoirs, the hydrocarbon layer protecting and high-speed drilling technique, and the rework technique for enhancing productivity. 展开更多
关键词 reserve abundance lithologic hydrocarbon reservoir hydrocarbon-rich sag sweet spot exploration technique
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New Data on Coal, Gypsum, Iron and Silica Sand Deposits and Geochemical Exploration (Pakistan): Revision of 25 Years History of Dinosaur Discoveries from Pakistan
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作者 Muhammad Sadiq Malkani 《Open Journal of Geology》 CAS 2024年第3期431-511,共81页
Discoveries of many coal seams at depths by drilling carried by Geological Survey of Pakistan in Sor Range and Harnai Gochina, extended the coal seams at depth which is challenge for mine owners to exploit feasibly. B... Discoveries of many coal seams at depths by drilling carried by Geological Survey of Pakistan in Sor Range and Harnai Gochina, extended the coal seams at depth which is challenge for mine owners to exploit feasibly. Bed to bed gypsum samplings (and their chemical analyses) of huge gypsum deposits from Sulaiman foldbelt is a base for industrialist and also planers to develop cement and gypsum industries to increase export and foreign exchange for the development of area and Pakistan. Low and high grade sedimentary iron deposits, silica sand and uranium host rocks and their extensions in Sulaiman and Kirthar foldbelts are presented. Anomalies of a few base metals arise as a result of geochemical exploration carried at part of Loralai District of Balochistan. Theropod dinosaurs were frequent in India, while Poripuchian titanosaurs (Sauropoda, Dinosauria) were frequent in Pakistan. Besides some ichnotaxa, many bone taxa such as 1 titanosauriform, 14 titanosaurian sauropod (including one new titanosaur), and 3 theropod dinosaurs are established from Pakistan. Among these 12 titanosaur species and 3 theropod species are named in about 10 km<sup>2</sup> area of Vitakri dome and 2 titanosaur species are named in about a few hundred square meter area of Mari Bohri (Kachi Bohri) which is about 10 km westward from Vitakri dome. Pakistan is a unique country which discoverd 14 diversified titanosaurs in a short area and also in a short period (67 - 66 million years ago/Ma). About 400 bones found from a few meter thick upper part of upper shale horizon of latest Maastrichtian Vitakri Formation which is base for titanosaur taxa. Cranial material is in low fraction (but include significant diverse snouts), caudal vertebrae are prominent, the cervicals, dorsals and sacrals have significant numbers, forelimb and hind limb bones have balanced fraction. Humeri, femora and tibiae are most common. To know the position of Pakistani titanosaurs among titanosaurs and sauropods, there is a need to extend list of characters for phylogenetic analyses. This broad feature list should include main characters of titanosaurs from Pakistan and also from global world. 展开更多
关键词 COAL GYPSUM IRONSTONE Silica sands Geochemical exploration Dinosaurs TITANOSAURIFORMES Titanosaurs Theropods REVISION BALOCHISTAN Pakistan
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Cu-Zn isotope compositions of hydrothermal sediments from the southern Mid-Atlantic Ridge:implications to the sediment formation and mineral exploration
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作者 Baoju YANG Lianhua HE +3 位作者 Chuanshun LI Qiannan HU Bingfu JIN Jihua LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1470-1485,共16页
Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in 2017.Sulfides and oxides in the samples wer... Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in 2017.Sulfides and oxides in the samples were separated,and Cu and Zn isotope compositions were analyzed.Results show that the ranges ofδ^(65)Cu values of the bulk sediments,sulfides,and oxides were 0.36‰-2.46‰,-0.21‰-1.10‰,and 0.68‰-1.52‰,respectively.Theδ^(65)Cu values of sulfides in four samples(46II-14,46II-30,46III-06,and 46II-09)were relatively low(-0.21‰-0.50‰),corresponding to theδ^(65)Cu values of sulfides from inactive old hydrothermal chimneys in northern Mid-Atlantic Ridge(n MAR),suggesting that the sulfides in the sediments were originated from collapsed dead chimney mainly.While theδ^(65)Cu values of the other two samples(46III-02 and 46III-08)were relatively high(1.10‰-0.96‰),corresponding to theδ^(65)Cu values for active hydrothermal chimneys sulfides in n MAR,which indicated that the sulfides in these two samples might mainly come from sulfide particles settled from active hydrothermal plume.Because of the high density of sulfide particles,they tended to settle near the hydrothermal vents first.Therefore,highδ^(65)Cu values of sulfides in 46III-02 and 46III-08 implied that undiscovered active hydrothermal vents near the sampling positions of 46III-02 in the Xunmei hydrothermal field and 46III-08 in the Tongguan hydrothermal field.Theδ^(66)Zn values of hydrothermal sediments and sulfides ranged 0.11‰-0.43‰and 0.29‰-0.67‰,respectively.In the four samples from the Xunmei hydrothermal field,a positive correlation was found between the distance of the sampling position from sulfide mineralized spot and the Zn isotopic ratio,showing that the greater the distance from the mineralized spot,the heavier the Zn isotope composition as seen in two samples(46II-30 and 46II-14)of the Xunmei-3 spot.This result aligned with the findings of Wilkinson et al.(2005)and Baumgartner et al.(2023),suggesting that the lower the Zn isotope composition,the closer it is to the hydrothermal vent.However,in the Xunmei hydrothermal field,the Zn isotope composition in the other two samples(46III-02and 46III-06)showed the opposite trend.This indicated that there might be an active hydrothermal vent near the sampling location of sample 46III-02.This observation aligned with the Cu isotope analysis results.This study showed that Cu-Zn isotopes are good indicators for understanding the formation mechanisms of hydrothermal sediments and for locating active hydrothermal vents. 展开更多
关键词 Cu-Zn isotope hydrothermal sediments mineral exploration southern Mid-Atlantic Ridge
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Research on Integrated Planning Method of Offshore Oil and Gas Exploration and Development 被引量:2
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作者 Xunda Wu 《International Journal of Geosciences》 2020年第7期483-491,共9页
Under the requirement of high-quality development, the research method of integrated model planning for offshore oil and gas exploration and development suitable for the western South China Sea is put forward. Based o... Under the requirement of high-quality development, the research method of integrated model planning for offshore oil and gas exploration and development suitable for the western South China Sea is put forward. Based on the new round of resource evaluation and exploration and development research in the western South China Sea, the in-depth research on underground oil and gas resources, surface development facilities, external factors and economic indexes are carried out to clarify the industrial layout of oil and gas development. The potential and prospect of oil and gas exploration and development were implemented, and the main external factors and corresponding measures affecting the planning were clarified in this paper. The economic evaluation model suitable for the region is established based on the analysis of internal rate of return, comprehensive barrel oil cost, critical price, financial net present value and other important indicators, and a set of planning and research methods suitable for the integration of exploration and development in the western South China Sea is finally formed. This method has been applied to the replacement reserve study of Weizhou X and Weizhou Y oil fields. It is found that the planned reserves and production are consistent with the actual ones, and good practical results have been achieved. 展开更多
关键词 West of South China Sea Integration of exploration and Development PLANNING RESERVES YIELD
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