期刊文献+
共找到2,636篇文章
< 1 2 132 >
每页显示 20 50 100
Non-PLL high-precision synchronous sampling method among lots of acoustics acquisition channels for underwater multilinear array seismic exploration system
1
作者 JIANG Jiajia CUI Jindong +6 位作者 WANG Xianquan LI Xiaodong ZENG Xianjun ZHOU Dasen YAO Qingwang DUAN Fajie FU Xiao 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2022年第1期41-50,共10页
Synchronous sampling is very essential in underwater multilinear array seismic exploration system in which every acquisition node(AN)samples analog signals by its own analog-digital converter(ADC).Aiming at the proble... Synchronous sampling is very essential in underwater multilinear array seismic exploration system in which every acquisition node(AN)samples analog signals by its own analog-digital converter(ADC).Aiming at the problems of complex synchronous sampling method and long locking time after varying sampling rate in traditional underwater seismic exploration system,an improved synchronous sampling model based on the master-slave synchronous model and local clock asynchronous drive with non phase locked loop(PLL)is built,and a high-precision synchronous sampling method is proposed,which combines the short-term stability of local asynchronous driving clock with the master-slave synchronous calibration of local sampling clock.Based on the improved synchronous sampling model,the influence of clock stability,transmission delay and phase jitter on synchronous sampling error is analyzed,and a high-precision calibration method of synchronous sampling error based on step-by-step compensation of transmission delay is proposed.The model and method effectively realize the immunity of phase jitter on synchronous sampling error in principle,and compensate the influence of signal transmission delay on synchronous sampling error.At the same time,it greatly reduces the complexity of software and hardware implementation of synchronous sampling,and solves the problem of long locking time after changing the sampling rate in traditional methods.The experimental system of synchronous sampling for dual linear array is built,and the synchronous sampling accuracy is better than 5 ns. 展开更多
关键词 seismic exploration system synchronous sampling non phase locked loop(PLL) local clock asynchronous drive transmission delay
在线阅读 下载PDF
Accurate Source-Receiver Positioning Method for a High-Resolution Deep-Towed Multichannel Seismic Exploration System 被引量:1
2
作者 LI Jing LIU Kai +5 位作者 WEI Zhengrong ZHANG Liancheng LIU Yangting PEI Yanliang LIU Chenguang LIU Baohua 《Journal of Ocean University of China》 CAS CSCD 2024年第2期415-426,共12页
The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high... The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high vertical and horizontal resolution.However,the quality of deep-towed seismic imaging hinges on accurate source-receiver positioning information.In light of existing technical problems,we propose a novel array geometry inversion method tailored for high-resolution deep-towed multichannel seismic exploration systems.This method is independent of the attitude and depth sensors along a deep-towed seismic streamer,accounting for variations in seawater velocity and seabed slope angle.Our approach decomposes the towed line array into multiline segments and characterizes its geometric shape using the line segment distance and pitch angle.Introducing optimization parameters for seawater velocity and seabed slope angle,we establish an objective function based on the model,yielding results that align with objective reality.Employing the particle swarm optimization algorithm enables synchronous acquisition of optimized inversion results for array geometry and seawater velocity.Experimental validation using theoretical models and practical data verifies that our approach effectively enhances source and receiver positioning inversion accuracy.The algorithm exhibits robust stability and reliability,addressing uncertainties in seismic traveltime picking and complex seabed topography conditions. 展开更多
关键词 high-resolution deep-towed multichannel seismic exploration source-receiver positioning array geometry inversion seawater heterogeneity seabed slope angle
在线阅读 下载PDF
Design and Implementation of a Multi-Sensor Based Object Detecting and Removing Autonomous Robot Exploration System
3
作者 Fan Wu Johnathan Williams 《Journal of Computer and Communications》 2014年第7期8-16,共9页
Developing autonomous mobile robot system has been a hot topic in AI area. With recent advances in technology, autonomous robots are attracting more and more attention worldwide, and there are a lot of ongoing researc... Developing autonomous mobile robot system has been a hot topic in AI area. With recent advances in technology, autonomous robots are attracting more and more attention worldwide, and there are a lot of ongoing research and development activities in both industry and academia. In complex ground environment, obstacles positions are uncertain. Path finding for robots in such environment is very hot issues currently. In this paper, we present the design and implementation of a multi-sensor based object detecting and moving autonomous robot exploration system, 4RE, with the VEX robotics design system. With the goals of object detecting and removing in complex ground environment with different obstacles, a novel object detecting and removing algorithms is proposed and implemented. Experimental results indicate that our robot system with our object detecting and removing algorithm can effectively detect the obstacles on the path and remove them in complex ground environment and avoid collision with the obstacles. 展开更多
关键词 AUTONOMOUS ROBOT exploration system OBJECT Detecting and Removing Algorithm Multiple Sensors
暂未订购
Networking autonomous material exploration systems through transfer learning
4
作者 Naoki Yoshida Yutaro Iwabuchi +1 位作者 Yasuhiko Igarashi Yuma Iwasaki 《npj Computational Materials》 2025年第1期4243-4251,共9页
Autonomous material exploration systems that integrate robotics,material simulations,and machine learning have advanced rapidly in recent years.Although their number continues to grow,these systemscurrently operate in... Autonomous material exploration systems that integrate robotics,material simulations,and machine learning have advanced rapidly in recent years.Although their number continues to grow,these systemscurrently operate in isolation,limiting the overall efficiency of autonomous material discovery.In analogy to how human researchers advance materials science by sharing knowledge and collaborating,autonomous systems can also benefit from networking and knowledge exchange.Here,we propose a framework in which multiple autonomous material exploration systems form a network via transfer learning,selectively utilizing relevant knowledge from other systems in real time.We demonstrate this approach using three distinct autonomous systems and show that such networking significantly enhances the efficiency of material discovery.Our results suggest that the proposed framework can enable the development of large-scale autonomous material exploration networks,ultimately accelerating progress in material development. 展开更多
关键词 transfer learning material simulations sharing knowledge autonomous material discoveryin ROBOTICS advance materials science machine learning autonomous material exploration systems
原文传递
High-throughput materials exploration system for the anomalousHall effect using combinatorial experiments and machine learning
5
作者 Ryo Toyama Yuma Iwasaki +3 位作者 Prabhanjan D.Kulkarni Hirofumi Suto Tomoya Nakatani Yuya Sakuraba 《npj Computational Materials》 2025年第1期3115-3123,共9页
The development of new materials exhibiting large anomalous Hall effect(AHE)is essential for realizing highly efficient spintronic devices.However,this development has been a time-consuming process due to the combinat... The development of new materials exhibiting large anomalous Hall effect(AHE)is essential for realizing highly efficient spintronic devices.However,this development has been a time-consuming process due to the combinatorial explosion for multielement systems and limited experimental throughput.In this study,we identify new materials exhibiting large AHE in heavy-metal-substituted Fe-based alloys using a high-throughput materials exploration method that combines deposition of compositionspread films using combinatorial sputtering,photoresist-free facile multiple-device fabrication using laser patterning,simultaneous AHE measurement of multiple devices using a customized multichannel probe,and prediction of candidate materials using machine learning.Based on experimental AHE data on Fe-based binary system alloyed with various single heavy metals,we perform machine learning analysis to predict the Fe-based ternary system containing two heavy metals for larger AHE.We experimentally confirm larger AHE in the predicted Fe–Ir–Pt system.Using scaling analysis,we reveal that the enhancement of AHE originates from the extrinsic contribution. 展开更多
关键词 machine learning large anomalous hall effect ahe high throughput materials exploration development new materials combinatorial experiments combinatorial explosion deposition compositionspread films identify new materials
原文传递
Design and mechanical optimization of multidirectional pressure-preserved coring system for deep-earth resource exploration
6
作者 Guikang Liu Yachen Xie Cong Li 《International Journal of Mining Science and Technology》 2025年第5期719-735,共17页
Pressure-preserved coring technologies are critical for deep-earth resource exploration but are constrained by the inability to achieve multidirectional coring,restricting exploration range while escalating costs and ... Pressure-preserved coring technologies are critical for deep-earth resource exploration but are constrained by the inability to achieve multidirectional coring,restricting exploration range while escalating costs and environmental impacts.We developed a multidirectional pressure-preserved coring system based on magnetic control for deep-earth environments up to 5000 m.The system integrates a magnetically controlled method and key pressure-preserved components to ensure precise self-triggering and self-sealing.It is supported by geometric control equations for optimizing structural stability.Their structure was verified and optimized through theoretical and numerical calculations to meet design objectives.To clarify the self-triggering mechanism in complex environments,a dynamic interference model was established,verifying stability during multidirectional coring.The prototype was fabricated,and functional tests confirmed that it met its design objectives.In a 300-meter-deep test inclined well,10 coring operations were completed with a 100%pressure-preserved success rate,confirming the accuracy of the dynamic interference model analysis.Field trials in a 1970-meter-deep inclined petroleum well,representative of complex environments,demonstrated an in-situ pressure preservation efficiency of 92.18%at 22 MPa.This system innovatively expands the application scope of pressure-preserved coring,providing technical support for efficient and sustainable deep resources exploration and mining. 展开更多
关键词 Deep mining Environmentally and economically sustainable deep-earth resource exploration Multidirectional pressure-preserved coring system Magnetic control technology Dynamic interference model Field validation
在线阅读 下载PDF
Major breakthroughs and significance of risk exploration for tight oil in Fuyu pay zone in the deep area of Gulong Sag,northern Songliao Basin,China
7
作者 BAI Xuefeng YANG Yu +2 位作者 LI Junhui CHEN Fangju ZHENG Qiang 《Petroleum Exploration and Development》 2026年第1期31-45,共15页
The concurrent exploration of shale oil wells in the Gulong Sag of the Songliao Basin has uncovered promising hydrocarbon shows in the Fuyu pay zone of the Lower Cretaceous Quantou Formation.To assess the hydrocarbon ... The concurrent exploration of shale oil wells in the Gulong Sag of the Songliao Basin has uncovered promising hydrocarbon shows in the Fuyu pay zone of the Lower Cretaceous Quantou Formation.To assess the hydrocarbon exploration potential of the Fuyu pay zone,this study systematically analyzes the main controlling factors for hydrocarbon accumulation,including source rock conditions,reservoir characteristics and migration capacity,in the deep area of the Gulong Sag,using seismic,drilling and core data,and reveals the hydrocarbon enrichment mechanism and accumulation model.The results indicate that the source rocks in the first member of Cretaceous Qingshankou Formation(Qing-1 Member)in the Gulong Sag are widely distributed,characterized by high quality,large area,high maturity and high hydrocarbon generation intensity,providing an ample oil source for the Fuyu pay zone.The Fuyu pay zone in the Gulong Sag features multi-phase channel sand bodies and beach-bar sands that are laterally superimposed and vertically stacked,forming large-scale sand-rich reservoir assemblages,which provide the storage space for tight oil enrichment.Influenced by overpressure pore preservation and dissolution-enhanced porosity,the porosity of the Fuyu pay zone can reach up to 13%,meeting the reservoir conditions necessary for large-scale tight oil enrichment.The episodic opening of hydrocarbon-source connected faults during the hydrocarbon expulsion period,combined with source-reservoir pressure differentials,drives the efficient charging and enrichment of hydrocarbons into the underlying tight reservoirs.The hydrocarbon accumulation model of the Fuyu pay zone is summarized as“source-reservoir juxtaposition,overpressure charging,lateral source-reservoir connection+vertical fault-directed bidirectional hydrocarbon supply,continuous sand body distribution,and large-scale enrichment in fault-horst belts”.A new insight for the deep area of the Gulong Sag is proposed as being sand-rich,having superior reservoirs,and being oil-rich.This insight guided the deployment of three risk exploration wells.The Well HT1H achieved a high-yield industrial oil flow rate of 35.27 t/d during testing,discovering light tight oil with low density and low viscosity.Through horizontal well volumetric fracturing treatment,the Well HT1H achieved the first high-yield breakthrough of tight oil in the deep area of the Gulong Sag,confirming the presence of geological conditions for large-scale hydrocarbon accumulation in this area.This expands the potential for hundred-million-ton tight oil resource additions in the Songliao Basin and deepens the theoretical understanding of continental tight oil accumulation. 展开更多
关键词 Songliao Basin Gulong Sag Cretaceous Qingshankou Formation Fuyu pay zone tight oil risk exploration exploration breakthrough enrichment pattern
在线阅读 下载PDF
New Year Message for 2026 from Petroleum Exploration and Development
8
作者 Editorial Office of Petroleum Exploration and Development 《Petroleum Exploration and Development》 2026年第1期F0002-F0002,共1页
Time flows with no stop,and seasons change in swift succession.As we bid farewell to 2025 and welcome the Spring Festival of 2026,the Editorial Office of Petroleum Exploration and Development extends our most heartfel... Time flows with no stop,and seasons change in swift succession.As we bid farewell to 2025 and welcome the Spring Festival of 2026,the Editorial Office of Petroleum Exploration and Development extends our most heartfelt gratitude and sincerest New Year wishes to our editorial board members,experts,authors,readers,and friends from all sectors. 展开更多
关键词 DEVELOPMENT new year message seasons change editorial office editorial board members petroleum exploration experts petroleum exploration development
在线阅读 下载PDF
Geochemistry,possible origin and exploration potential of crude oils from Neogene Shawan Formation in the Chepaizi Uplift,Junggar Basin(NW China)based on biomarker recovery method
9
作者 Chen-yu Wang Xiang-chun Chang +4 位作者 You-de Xu Bing-bing Shi Tian-chen Ge Wei-zheng Gao Lei Su 《China Geology》 2026年第1期86-101,共16页
The Neogene Shawan Formation in the Chepaizi Uplift of the Junggar Basin(NW China)has obtained high oil flow,demonstrating a good potential for oil and gas exploration.The multi-source hydrocarbon generation backgroun... The Neogene Shawan Formation in the Chepaizi Uplift of the Junggar Basin(NW China)has obtained high oil flow,demonstrating a good potential for oil and gas exploration.The multi-source hydrocarbon generation background and strong tectonic activity have led to the simultaneous production of heavy oil and light oil from multi-layer in the area,which makes it very difficult to identify oil origins,presently,the hot debate on the oil origins needs to be clarified.In this paper,due to the selective consumption of different types of compounds in crude oils by severe and intense biodegradation,the commonly used oilsource correlation tools are ineffective or may produce misleading results,this study adopted a biomarker recovery method based on the principle of mass conservation that uses the sum of the mass of the residual biomarkers and their corresponding biodegradation products to obtain the mass of the original biomarkers,improving the reliability of oil origins determination.Based on the nature and occurrence of crude oils,the investigated oils are subdivided into three types,Group A,Group B and Group C.Group A,light oils occurred mainly in lower structure Neogene Shawan Formation in the western Chepaizi Uplift,while Group B,heavy oils occurred mainly in higher structure Neogene Shawan Formation in the western Chepaizi Uplift.The two types of crude oils may come from the mixed source of Jurassic Badaowan Formation source rocks(J_(1)b)and Paleogene Anjihaihe Formation source rocks(E_(2-3)a)in the Sikeshu Sag,and Jurassic Badaowan Formation source rocks(J_(1)b)are the main source of crude oils.Group C,heavy oils occurred mainly in Neogene Shawan Formation in the eastern Chepaizi Uplift,showing good correlation with the Permian(P_(1)f and P_(2)w)source rocks in the Shawan Sag.At the same time,by combining stable carbon isotope and parameters related to triaromatic steroids,the accuracy of the oilsource correlation results by biomarker recovery method was further verified. 展开更多
关键词 Biomarker recovery Oil-source correlation Stable carbon isotope Heavy and light oil identify Oil-gas exploration potential Chepaizi Uplift Neogene Shawan Formation Petroleum exploration engineering Junggar Basin
在线阅读 下载PDF
AI and ML in groundwater exploration and water resources management:Concepts,methods,applications,and future directions
10
作者 Adla Andalu MGopal Naik Sandeep Budde 《Journal of Groundwater Science and Engineering》 2026年第1期100-122,共23页
The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This rev... The integration of Artificial Intelligence(AI)and Machine Learning(ML)into groundwater exploration and water resources management has emerged as a transformative approach to addressing global water challenges.This review explores key AI and ML concepts,methodologies,and their applications in hydrology,focusing on groundwater potential mapping,water quality prediction,and groundwater level forecasting.It discusses various data acquisition techniques,including remote sensing,geospatial analysis,and geophysical surveys,alongside preprocessing methods that are essential for enhancing model accuracy.The study highlights AI-driven solutions in water distribution,allocation optimization,and realtime resource management.Despite their advantages,the application of AI and ML in water sciences faces several challenges,including data scarcity,model reliability,and the integration of these tools with traditional water management systems.Ethical and regulatory concerns also demand careful consideration.The paper also outlines future research directions,emphasizing the need for improved data collection,interpretable models,real-time monitoring capabilities,and interdisciplinary collaboration.By leveraging AI and ML advancements,the water sector can enhance decision-making,optimize resource distribution,and support the development of sustainable water management strategies. 展开更多
关键词 Artificial intelligence Machine learning Groundwater exploration Hydrological modeling Remote sensing applications Water resources management
在线阅读 下载PDF
Hotspots,trends,and regional focus on oil or gas exploration:A bibliometric comparative study
11
作者 Jihong Wang Zhongkai Li +1 位作者 Jianguo Wang Zhiqiang Li 《Deep Underground Science and Engineering》 2026年第1期296-311,共16页
Oil and gas resources serve as the driving force for economic and social development.This rapid development of science and technology has accelerated the exploration,development,and utilization of oil and gas resource... Oil and gas resources serve as the driving force for economic and social development.This rapid development of science and technology has accelerated the exploration,development,and utilization of oil and gas resources,and thus led to spurts in related research.However,the research trends in global oil and gas exploration vary with the progress of science and technology as well as social demands.Accordingly,they are not easily captured.This study explores the research trends in global oil and gas exploration through the bibliometric analysis of 3460 articles on oil and gas exploration collected from the Web of Science database and published from 2013 to 2023.The research hotspots,objects,regional distribution,methods,and evaluation methods in oil and gas exploration are analyzed,and the direction of development of oil and gas exploration is presented on this basis.The research characteristics of four major countries or regions related to oil and gas exploration were further investigated and compared.The results show that the number of publications on oil and gas exploration research has been continuously increasing in the past decade,with China ranking the top in terms of publications.Given the continuously evolving global energy demand,exploration of unconventional oil and gas,application of digital technology,deep and emerging regional resource exploration,and environmentally friendly and low-carbon source exploration will be future research hotspots. 展开更多
关键词 bibliometric analysis oil or gas exploration RESOURCES shale gas unconventional energy
原文传递
Dynamic reconstruction of the source-to-sink system of the Paleogene Enping Formation in the Baiyun Sag,Pearl River Mouth Basin,China:Insights from stratigraphic forward modeling
12
作者 GAO Jianlei LIU Keyu 《Petroleum Exploration and Development》 2026年第1期152-166,共15页
Traditional source-to-sink analyses cannot effectively characterize deep-time sedimentary processes involving multiple sediment sources and the spatiotemporal evolution of sediment contributions from different sources... Traditional source-to-sink analyses cannot effectively characterize deep-time sedimentary processes involving multiple sediment sources and the spatiotemporal evolution of sediment contributions from different sources.In this study,a dynamic,quantitative source-to-sink analysis approach using stratigraphic forward modeling(SFM)is proposed,and it is applied to the Paleogene Enping Formation in the Baiyun Sag,Pearl River Mouth Basin.The built-in spatiotemporal provenance tagging of the model assigns a unique time-source label to sediments from each provenance,making each source's contribution identifiably“labeled”in the simulated formation,and thus enabling a direct precise tracking and high spatiotemporal resolution quantification of such contributions.Five pseudo-wells(from proximal to distal locations)in the Baiyun Sag were analyzed.The simulation results quantitatively represent the varied proportion of contribution of each source at different locations and in different periods and verify the proposed approach's operability and accuracy of the proposed approach.The simulated 3D deposit distribution shows a high agreement with the measured stratigraphic data,validating the model's reliability.Results reveal significant spatiotemporal changes in the Enping sedimentary system.In the late stage of Enping Formation deposition,a distal source supply from the northern part of the sag became dominant,the depocenter migrated northward to the deepwater area,and large-scale deltaic sand bodies extensively progradating into the sag were formed.The modeled 3D deposit distribution indicates that extensive high-quality reservoir sandstones are likely present across the deepwater area of the Baiyun Sag,which are identified as key exploration targets.Compared to traditional static approaches,the SFM-based dynamic simulation markedly enhances the spatiotemporal resolution of source-to-sink analysis and quantitatively captures the sedimentary system's responses to tectonic activity,base-level fluctuations and other external drivers.The proposed approach provides a novel quantitative framework for investigating complex,deep-time,multi-source systems,and offers an effective tool for reservoir prediction and hydrocarbon exploration planning in underexplored deepwater areas. 展开更多
关键词 source-to-sink system stratigraphic forward modeling reservoir prediction deepwater hydrocarbon exploration Baiyun Sag Pearl River Mouth Basin Paleogene Enping Formation
在线阅读 下载PDF
Research on Casing Techniques for Horizontal Drilling in Fractured Strata During Water Conveyance Tunnel Exploration
13
作者 Changyou Dai Zijia Ge Shulei Zhang 《Journal of Environmental & Earth Sciences》 2026年第3期154-168,共15页
The most common aspect of water conveyance tunnel construction is the use of horizontal and sub-horizontal exploration drilling of headings of a tunnel to predict geology and groundwater conditions.The instability of ... The most common aspect of water conveyance tunnel construction is the use of horizontal and sub-horizontal exploration drilling of headings of a tunnel to predict geology and groundwater conditions.The instability of boreholes,extreme loss of circulation,and high-head inflow are also common in fractured strata,which often inhibit completion of probe holes and the reliability of coring,packer testing,and grouting tests.Casing,consequently,is a significant enabling technology to stabilize fractured intervals and has a hydraulic isolation under coupled mechanical and hydrogeological disturbances.The review is a synthesis of research and engineering experience on methods of casing to be used in horizontal drilling of fractured rock masses used in the exploration of water conveyance tunnels.The geological and working environment is initially outlined with a focus on fracture-adaptable instability processes and the special goings on of underground drilling,such as the restricted workspace,cuttings difficult to move,and fast movement of the competent and crushed regions.Types of casing systems are then listed,including both standard threaded steel strings and telescopic programs,and more specialized casing system types,including expandable casing,swellable sealing elements,and external casing packers.Special focus is made on the sealing of annulus in horizontal holes,wherein slurry loss,gravity segregation,and non-uniform borehole geometry usually worsen isolation.Lastly,the article suggests adaptive choice of strategy according to real-time drilling reaction,and research priorities,such as tunnel-specific performance measurements,coupled hydro-mechanical modelling,and field trials of sophisticated sealing material and data-driven choice making. 展开更多
关键词 Horizontal exploration Drilling Fractured Strata Casing Techniques Annulus Sealing Water Conveyance Tunnel
在线阅读 下载PDF
2025 global progress in rare earth exploration
14
作者 Hui Guo Jie Meng +2 位作者 Ya-ping Li Bo-ran Guo Zi-guo Hao 《China Geology》 2026年第1期221-226,共6页
In 2025,the global rare earth exploration and development sector achieved breakthroughs across multiple fronts.Projects advanced intensively across the Americas,Oceania,Africa,and Europe,with significant growth in res... In 2025,the global rare earth exploration and development sector achieved breakthroughs across multiple fronts.Projects advanced intensively across the Americas,Oceania,Africa,and Europe,with significant growth in resources,continuous emergence of new deposits,and strong impetus injected into the industry by technological innovation and policy support.The global rare earth resource supply pattern was further optimized (Table 1).1.Fruitful results in resource growth and new deposit discoveriesBrazil emerged as a core region for resource growth.The Colossus rare earth deposit saw a 150%increase in resources and announced its first reserve estimate.The Caldeira rare earth deposit’s resource estimate grew by 50%.The combined ore resources in the Caladão rare earth deposit’s Zones A and B reached 5.72×10~8 tonnes,with a total rare earth oxide(TREO) grade of 0.1506%,concurrently hosting 2.29×10~4tonnes of gallium metal resources. 展开更多
关键词 technological innovation new deposit discoveries rare earth policy supportthe rare earth resource supply pattern resource growth rare earth exploration development policy support
在线阅读 下载PDF
Noise-driven enhancement for exploration:Deep reinforcement learning for UAV autonomous navigation in complex environments
15
作者 Haotian ZHANG Yiyang LI +1 位作者 Lingquan CHENG Jianliang AI 《Chinese Journal of Aeronautics》 2026年第1期454-471,共18页
Unmanned Aerial Vehicle(UAV)plays a prominent role in various fields,and autonomous navigation is a crucial component of UAV intelligence.Deep Reinforcement Learning(DRL)has expanded the research avenues for addressin... Unmanned Aerial Vehicle(UAV)plays a prominent role in various fields,and autonomous navigation is a crucial component of UAV intelligence.Deep Reinforcement Learning(DRL)has expanded the research avenues for addressing challenges in autonomous navigation.Nonetheless,challenges persist,including getting stuck in local optima,consuming excessive computations during action space exploration,and neglecting deterministic experience.This paper proposes a noise-driven enhancement strategy.In accordance with the overall learning phases,a global noise control method is designed,while a differentiated local noise control method is developed by analyzing the exploration demands of four typical situations encountered by UAV during navigation.Both methods are integrated into a dual-model for noise control to regulate action space exploration.Furthermore,noise dual experience replay buffers are designed to optimize the rational utilization of both deterministic and noisy experience.In uncertain environments,based on the Twin Delay Deep Deterministic Policy Gradient(TD3)algorithm with Long Short-Term Memory(LSTM)network and Priority Experience Replay(PER),a Noise-Driven Enhancement Priority Memory TD3(NDE-PMTD3)is developed.We established a simulation environment to compare different algorithms,and the performance of the algorithms is analyzed in various scenarios.The training results indicate that the proposed algorithm accelerates the convergence speed and enhances the convergence stability.In test experiments,the proposed algorithm successfully and efficiently performs autonomous navigation tasks in diverse environments,demonstrating superior generalization results. 展开更多
关键词 Action space exploration Autonomous navigation Deep reinforcement learning Twin delay deep deterministic policy gradient Unmanned aerial vehicle
原文传递
Total play system of natural gas in the northern continental margin of the South China Sea
16
作者 ZHANG Gongcheng CHEN Ying +10 位作者 HONG Sijie FENG Congjun LIAO Jin JI Mo LIU Shixiang WANG Panrong HU Gaowei LI Anqi HAO Jianrong WANG Ke GUO Jia 《Petroleum Exploration and Development》 2026年第1期46-60,共15页
For the next exploration direction and integrated evaluation and optimization of targets for the northern continental margin of the South China Sea,this paper proposes the concept of the“total natural gas play system... For the next exploration direction and integrated evaluation and optimization of targets for the northern continental margin of the South China Sea,this paper proposes the concept of the“total natural gas play system”based on the principles of systems theory.Integrating over 60 years of exploration achievements in the four major basins,the paper studies the basic geological conditions,hydrocarbon accumulation models and distribution characteristics of the system.With the core principle of“source-heat controlling natural gas and play-stratigraphy controlling accumulation”,it analyzes the distribution law of natural gas reservoirs covering“intra-sag,sag margin,extra-sag”and multi-stratigraphic sequences.The study shows that under the joint control of source and heat,the northern continental margin of the South China Sea can be divided into two major gas areas:the southern area dominated by coal-type gas and the northern area dominated by oil-type gas,with the former as the main body.Based on the distribution location of hydrocarbon kitchen,the total gas plays are classified into three types:intra-sag,sag margin and extra-sag.In the oil-type gas area of the northern coastal zone,the proportion of intra-sag natural gas is relatively high;in the coal-type gas area of the southern offshore zone,the proportions of intra-sag and sag margin natural gas are relatively large;while the scale of gas accumulation in the extra-sag plays is relatively small.Finally,it is clearly pointed out that the southern offshore zone is the main direction for the next natural gas exploration in the northern South China Sea.Specifically,in the offshore zone,the intra-sag play and middle-deep layers of the sag margin play in the Yingzhong sag should be focused for the Yinggehai Basin;the intra-sag play and sag margin play in the central depression are targets for the Qiongdongnan Basin;the middle-deep layers of the intra-sag play are targets for the Baiyun sag of the Pearl River Mouth Basin.Furthermore,in the northern depression zone of the Pearl River Mouth Basin within the coastal zone,the main exploration directions include the middle-deep layers of the intra-sag play in the Huizhou sag and the middle-deep layers of the intra-sag play in the Enping sag;in the Beibu Gulf Basin,the main directions are the middle-deep layers of the intra-sag play in the Weixinan sag and the middle-deep layers of the intra-sag play in the Haizhong sag. 展开更多
关键词 coal-type gas oil-type gas total play system of natural gas exploration target Yinggehai Basin Qiongdongnan Basin Pearl River Mouth Basin Beibu Gulf Basin South China Sea
在线阅读 下载PDF
Various approaches of laparoscopic common bile duct exploration plus primary duct closure for choledocholithiasis:A systematic review and meta-analysis 被引量:67
17
作者 Ming-Yan He Xia-Dong Zhou +3 位作者 Hao Chen Peng Zheng Fa-Zhan Zhang Wei-Wei Ren 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第3期183-191,共9页
Background: Common bile duct (CBD) stones may occur in up to 3%–14.7% of all patients with cholecystectomy.Various approaches of laparoscopic CBD exploration plus primary duct closure (PDC) are the most commonly... Background: Common bile duct (CBD) stones may occur in up to 3%–14.7% of all patients with cholecystectomy.Various approaches of laparoscopic CBD exploration plus primary duct closure (PDC) are the most commonly used and the best methods to treat CBD stone. This systematic review was to comparethe effectiveness and safety of the various approaches of laparoscopic CBD exploration plus PDC forcholedocholithiasis 展开更多
关键词 LAPAROSCOPY CHOLEDOCHOLITHIASIS Common bile duct exploration Primary duct closureMeta-analysis
暂未订购
A scale-integrated exploration model for orogenic gold deposits based on a mineral system approach 被引量:9
18
作者 David I.Groves M.Santosh Liang Zhang 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第3期719-738,共20页
Concept-based orogenic gold exploration requires a scale-integrated approach using a robust mineral system model.Most genetic hypotheses for orogenic gold deposits that involve near-surface or magmatic-hydrothermal fl... Concept-based orogenic gold exploration requires a scale-integrated approach using a robust mineral system model.Most genetic hypotheses for orogenic gold deposits that involve near-surface or magmatic-hydrothermal fluids are now negated in terms of a global mineral system model.Plausible models involve metamorphic fluids,but the fluid source has been equivocal.Crustal metamorphic-fluid models are most widely-accepted but there are serious problems for Archean deposits,and numerous Chinese provinces,including Jiaodong,where the only feasible fluid source is sub-crustal.If all orogenic gold deposits define a coherent mineral system,there are only two realistic sources of fluid and gold,based on their syn-mineralization geodynamic settings.These are from devolatilization of a subducted oceanic slab with its overlying gold-bearing sulfide-rich sedimentary package,or release from mantle lithosphere that was metasomatized and fertilized during a subduction event,particularly adjacent to craton margins.In this model,CO_2 is generated during decarbonation and S and ore-related elements released from transformation of pyrite to pyrrhotite at about 500 ℃.This orogenic gold mineral system can be applied to conceptual exploration by first identifying the required settings at geodynamic to deposit scales.Within these settings,it is then possible to define the critical gold mineralization processes in the system:fertility,architecture,and preservation.The geological parameters that define these processes,and the geological,geophysical and geochemical proxies and responses for these critical parameters can then be identified.At the geodynamic to province scales,critical processes include a tectonic thermal engine and deep,effective,fluid plumbing system driven by seismic swarms up lithosphere-scale faults in an oblique-slip regime during uplift late in the orogenic cycle of a convergent margin.At the district to deposit scale,the important processes are fluid focussing into regions of complex structural geometry adjacent to crustal-scale plumbing systems,with gold deposition in trap sites involving complex conjugations of competent and/or reactive rock sequences and structural or lithological fluid caps.Critical indirect responses to defined parameters change from those generated by geophysics to those generated by geochemistry with reduction in scale of the mineral system-driven conceptual exploration. 展开更多
关键词 MINERAL systems OROGENIC GOLD Sub-crustal fluids CONVERGENT MARGINS GOLD exploration
在线阅读 下载PDF
Hydrodynamic Links between Shallow and Deep Mineralization Systems and Implications for Deep Mineral Exploration 被引量:11
19
作者 CHI Guoxiang XU Deru +5 位作者 XUE Chunji LI Zenghua Patrick LEDRU DENG Teng WANG Yumeng SONG Hao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第1期1-25,共25页
Deep mineral exploration is increasingly important for finding new mineral resources but there are many uncertainties.Understanding the factors controlling the localization of mineralization at depth can reduce the ri... Deep mineral exploration is increasingly important for finding new mineral resources but there are many uncertainties.Understanding the factors controlling the localization of mineralization at depth can reduce the risk in deep mineral exploration.One of the relatively poorly constrained but important factors is the hydrodynamics of mineralization.This paper reviews the principles of hydrodynamics of mineralization,especially the nature of relationships between mineralization and structures,and their applications to various types of mineralization systems in the context of hydrodynamic linkage between shallow and deep parts of the systems.Three categories of mineralization systems were examined,i.e.,magmatic-hydrothermal systems,structurally controlled hydrothermal systems with uncertain fluid sources,and hydrothermal systems associated with sedimentary basins.The implications for deep mineral exploration,including potentials for new mineral resources at depth,favorable locations for mineralization,as well as uncertainties,are discussed. 展开更多
关键词 HYDRODYNAMICS structural control of mineralization mineral systems shallow and deep mineralization deep mineral exploration
在线阅读 下载PDF
Marine Engineering Geological Exploration Information System(MEGEIS):A GIS-based Application to Marine Resources Exploitation 被引量:3
20
作者 SU Tianyun LIU Baohua +2 位作者 ZHAI Shikui LIANG Ruicai ZHENG Yanpeng 《Journal of Ocean University of China》 SCIE CAS 2007年第3期226-230,共5页
Based on the ArcGIS geographic information system and the ORACLE database management system,this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System(MEGEIS). By ... Based on the ArcGIS geographic information system and the ORACLE database management system,this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System(MEGEIS). By analyzing system structure,designing function modules and discussing data management,this paper systematically proposes a framework of technol-ogy to integrate,manage,and analyze the seabed information comprehensively. Then,the technology is applied to the design and development of the Bohai Sea Oilfield Paradigm Area Information System. The system can not only meet the practical demands of marine resources exploration and exploitation in the Bohai Sea oilfield,but also serve as a preparatory work in theory and technology for the realization of the 'Digital Seabed'. 展开更多
关键词 geographic information system (GIS) Digital Oilfield marine resources exploitation Digital Seabed Marine Engineering Geological exploration Information system (MEGEIS)
在线阅读 下载PDF
上一页 1 2 132 下一页 到第
使用帮助 返回顶部