The exploration/exploitation perspective is a well-known concept in the strategic management field;however,it has seldom been used to explore and analyze strategy at a national level.This study utilizes this perspecti...The exploration/exploitation perspective is a well-known concept in the strategic management field;however,it has seldom been used to explore and analyze strategy at a national level.This study utilizes this perspective to analyze China's eco-innovation mode in response to climate change.By categorizing eco-innovation into radical and incremental eco-innovation,we examine the relationship between these concepts using Y02 patents as a proxy and panel data from 30 Chinese provinces from 2004 to 2015.The results show that eco-innovation as a whole as well as both radical and incremental innovations are drivers for reducing carbon emissions.Furthermore,contradictory to most previous empirical results related to the complementarity hypothesis,we find a complementary relationship between radical and incremental eco-innovation.These results collectively represent China's unique eco-innovation mode,confirming the assumed diversity of eco-innovation models in different contexts.The results also show the significant positive effects of economic development,urbanization level,industrial structure,and China's opening up on carbon emissions,indicating that economic and social development have not yet been completely dissociated from carbon emissions in China.展开更多
In order to tradeoff exploration/exploitation and inspired by cell genetic algorithm a cellshift crossover operator for evolutionary algorithm (EA) is proposed in this paper. The definition domain is divided into n-...In order to tradeoff exploration/exploitation and inspired by cell genetic algorithm a cellshift crossover operator for evolutionary algorithm (EA) is proposed in this paper. The definition domain is divided into n-dimension cubic sub-domains (cell) and each individual locates at an ndimensional cube. Cell-shift crossover first exchanges the cell numbers of the crossover pair if they are in the different cells (exploration) and subsequently shift the first individual from its initial place to the other individual's cell place. If they are already in the same cell heuristic crossover (exploitation) is used. Cell-shift/heuristic crossover adaptively executes exploration/exploitation search with the vary of genetic diversity. The cell-shift EA has excellent performance in terms of efficiency and efficacy on ten usually used optimization benchmarks when comparing with the recent well-known FEP evolutionary algorithm.展开更多
From a harmonized structural map at the scale of a portion of SW Burkina Faso (90 × 80 km2), we targeted prospective zones on the basis of structural criteria and structure-geology relationships. The map was cons...From a harmonized structural map at the scale of a portion of SW Burkina Faso (90 × 80 km2), we targeted prospective zones on the basis of structural criteria and structure-geology relationships. The map was constructed from an aeromagnetic image, and the geology was deduced from old geological maps. The procedure involved extracting the magnetic fabric and deducing the deformation gradients, which led to the identification of shear zones. Analysis and interpretation of the structural geometry of the obtained structural pattern led us to target areas of interference between structures or geology-structures interplays, which are conducive to the deposition of metallic elements. The subsequent overlay of known gold prospects and deposits documented in the region revealed the validity of the predefined prospects. This result reinforces the applicability of the methodology as a first-order regional approach to mineral exploration.展开更多
In mid-May,good news came from Tajikistan,the country of high mountains.The Tajikistan Bogda Mountain geological exploration and sampling project,which had been dormant for over a decade,achieved a key breakthrough af...In mid-May,good news came from Tajikistan,the country of high mountains.The Tajikistan Bogda Mountain geological exploration and sampling project,which had been dormant for over a decade,achieved a key breakthrough after years of careful research,multi-party collaboration,and optimization of various plans,launching a new round of field exploration and testing work.展开更多
Near-surface geological defects pose a serious threat to human life and infrastructure.Hence,the exploration of geological hazards is essential.Currently,there are various geological hazard exploration methods;however...Near-surface geological defects pose a serious threat to human life and infrastructure.Hence,the exploration of geological hazards is essential.Currently,there are various geological hazard exploration methods;however,those require improvements in terms of economic feasibility,convenience,and lateral resolution.To address this,this study examined an extraction method to determine spatial autocorrelation velocity dispersion curves for application in near-surface exploration.展开更多
Economic violence is a form of domestic violence that extends beyond physical harm,affecting victims’economic stability and independence.This situation perpetuates gender inequality and also reinforces the cycle of g...Economic violence is a form of domestic violence that extends beyond physical harm,affecting victims’economic stability and independence.This situation perpetuates gender inequality and also reinforces the cycle of gender-based violence.With definitions of economic violence broadening to encompass a range of coercive and manipulative behaviors-from financial abuse in domestic violence scenarios to the economic harassment faced by stay-at-home moms-understanding this form of exploitation is crucial for crafting effective interventions.This article aims to delve into various facets of economic violence,including its definition,prevalence,and the stark realities it creates for its victims.Following the search of international databases:Social Work Abstracts(EBSCO),Psychology Abstracts,Family and Women Studies Worldwide,Psychiatry Online,Psych INFO(including Psych ARTICLES),PubMed,Wiley,and Scopus,60 peer-reviewed articles that met all inclusion criteria were included in the paper.Our review clarifies that looking forward,the call for a comprehensive understanding of economic violence,enhanced legal frameworks,and the strengthening of supportive networks underscore the multidisciplinary approach required to combat this issue effectively.展开更多
On June 3,Scopus,a database owned by Elsevier,released CiteScore 2024 metrics for academic journal evaluation.Both the Chinese and English editions of Petroleum Exploration and Development achieved record highs in the...On June 3,Scopus,a database owned by Elsevier,released CiteScore 2024 metrics for academic journal evaluation.Both the Chinese and English editions of Petroleum Exploration and Development achieved record highs in the past year,ranking among the top in various categories.The CiteScore of the Chinese edition increased to 9.9 in 2024 from 8.4 in 2023,ranking 13th out of 330 journals in the Earth and Planetary Sciences:Geology category and 2lst out of 239 journals in the Earth and Planetary Sciences:Geotechnical Engineering and Engineering Geology category.展开更多
China’s energy resource endowment is characterized by being“poor in oil,scarce in gas,and rich in coal”,a fundamental national condition that determines the uniqueness of China’s energy strategy.At the beginning o...China’s energy resource endowment is characterized by being“poor in oil,scarce in gas,and rich in coal”,a fundamental national condition that determines the uniqueness of China’s energy strategy.At the beginning of the 20th century,foreign experts and scholars generally concluded and claimed that China was an“oil-poor country”lacking the geological conditions for hydrocarbon formation.展开更多
At the turn of the new spring,as we bid farewell to 2024 and welcome the Spring Festival of 2025,our entire editorial team of Petroleum Exploration and Development extends heartfelt gratitude and sincere New Year'...At the turn of the new spring,as we bid farewell to 2024 and welcome the Spring Festival of 2025,our entire editorial team of Petroleum Exploration and Development extends heartfelt gratitude and sincere New Year's greetings to our editorial board,experts,authors,readers,and friends from all fields!展开更多
Sent out at 1:31am GMT+8 on May 29 by a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Sichuan province,China,Tianwen-2,the second mission of China’s Planetary Exploration Program,correctly ...Sent out at 1:31am GMT+8 on May 29 by a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Sichuan province,China,Tianwen-2,the second mission of China’s Planetary Exploration Program,correctly entered the transfer trajectory toward an asteroid named 2016HO3 after flying for 18 minutes.Its solar wings unfolded properly,signaling a successful start,and primed for the next stage of its mission.展开更多
The advancement of intelligent mining in open-pit operations has imposed higher demands on geological transparency,aiming to provide a robust foundation for intelligent drilling and charging.In this study,a linear arr...The advancement of intelligent mining in open-pit operations has imposed higher demands on geological transparency,aiming to provide a robust foundation for intelligent drilling and charging.In this study,a linear array of 120 nodal seismometers was deployed along the surfaces of the C8 and C9 platforms at Fenghuang Mountain to investigate cavities within the rock mass and prevent improper intelligent charging.The seismometers were 1 m apart along measurement lines,with a 2-m spacing between lines,and the monitoring time for each line was set at 2 h.This deployment was paired with spatial autocorrelation and station autocorrelation to analyze ambient noise seismic data and image the velocity and structure within the rock mass.The results demonstrate that the locations and sizes of cavities or loose structures can be accurately identified at the prepared excavation site.Compared with traditional geological exploration methods for openpit mines,the approach in this study off ers higher accuracy,greater efficiency,reduced labor intensity,and insensitivity to water conditions.Ambient noise seismic imaging for detecting adverse geological conditions in open-pit mines provides critical insights and references for intelligent mining advancements.展开更多
This study investigated proactive personality effects on employment preparation and the mediating roles of self-efficacy and career exploration behaviors in this relationship.The study sample comprised 445 university ...This study investigated proactive personality effects on employment preparation and the mediating roles of self-efficacy and career exploration behaviors in this relationship.The study sample comprised 445 university students(68.3%female;aged 20 to 24)from a university in central China.The participants completed measures to assess proactive personality,employment preparation,self-efficacy,and career exploration behaviors.Structural equation modeling analysis results indicated that proactive personality predicted higher employment preparation;Self-efficacy and career exploration behaviors partially mediated this relationship.Specifically,career exploration behaviors had a stronger mediating effect than self-efficacy on the total effect(34.71%vs.28.89%).The findings suggest proactive personality is key to employment preparation through self-belief and willingness to explore the job market.Higher education career counseling and mental health education programs should provide targeted training to promote career exploration by the student’s personal attributes for best match employment preparation.展开更多
Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have bee...Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields.展开更多
Autonomous driving technology is constantly developing to a higher level of complex scenes,and there is a growing demand for the utilization of end-to-end data-driven control.However,the end-to-end path tracking proce...Autonomous driving technology is constantly developing to a higher level of complex scenes,and there is a growing demand for the utilization of end-to-end data-driven control.However,the end-to-end path tracking process often encounters challenges in learning efficiency and generalization.To address this issue,this paper designs a deep deterministic policy gradient(DDPG)-based reinforcement learning strategy that integrates imitation learning and feedforward exploration in the path following process.In imitation learning,the path tracking control data generated by the model predictive control(MPC)method is used to train an end-to-end steering control model of a deep neural network.Another feedforward exploration behavior is predicted by road curvature and vehicle speed,and adds it and imitation learning to the DDPG reinforcement learning to obtain decision-making experience and action prediction behavior of the path tracking process.In the reinforcement learning process,imitation learning is used to update the pre-training parameters of the actor network,and a feedforward steering technique with random noise is adopted for strategy exploration.In the reward function,a hierarchical progressive reward form and a constrained objective reward function referring to MPC are designed,and the actor-critic network architecture is determined.Finally,the path tracking performance of the designed method is verified by comparing various training results,simulations,and HIL tests.The results show that the designed method can effectively utilize pre-training and feedforward prior experience to obtain optimal path tracking performance of an autonomous vehicle,and has better generalization ability than other methods.This study provides an efficient control scheme for improving the end-to-end control performance of autonomous vehicles.展开更多
Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework f...Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework for embodied visual exploration that possesses the efficient exploration capabilities of deep reinforcement learning(DRL)-based exploration policies and leverages feature-based visual odometry(VO) for more accurate mapping and positioning results. An improved local policy is also proposed to reduce tracking failures of feature-based VO in weakly textured scenes through a refined multi-discrete action space, keyframe fusion, and an auxiliary task. The experimental results demonstrate that Ne OR has better mapping and positioning accuracy compared to other entirely learning-based exploration frameworks and improves the robustness of feature-based VO by significantly reducing tracking failures in weakly textured scenes.展开更多
Renewable energy resources,including geothermal,are crucial for sustainable environmental management and climate change mitigation,offering clean,reliable,and low-emission alternatives to fossil fuels that reduce gree...Renewable energy resources,including geothermal,are crucial for sustainable environmental management and climate change mitigation,offering clean,reliable,and low-emission alternatives to fossil fuels that reduce greenhouse gases and support ecological balance.In this study,geographic information system(GIS)predictive analysis was employed to explore geothermal prospects,promoting environmental sustainability by reducing the dependence on fossil energy resources.Spatial and statistical analysis including the attribute correlation analysis was used to evaluate the relationship between exploration data and geothermal energy resources represented by hot springs.The weighted sum model was then used to develop geothermal predictive maps while the accuracy of prediction was determined using the receiver operating characteristic/area under curve(ROC/AUC)analysis.Based on the attribute correlation analysis,exploration data relating to geological structures,host rock(Asu River Group)and sedimentary contacts were the most critical parameters for mapping geothermal resources.These parameters were characterized by a statistical association of 0.52,0.48,and 0.46 with the known geothermal occurrences.Spatial data integration reveals the central part of the study location as the most prospective zone for geothermal occurrences.This zone occupies 14.76%of the study location.Accuracy assessment using the ROC/AUC analysis suggests an efficiency of 81.5%for the weight sum model.GIS-based multi-criteria analysis improves the identification and evaluation of geothermal resources,leading to better decision-making.展开更多
Deep space is incredibly quiet,but once astronauts leave the station,they must contend with extreme temperatures,fluctuating pressures,and high levels of radiation.Their spacesuits are equipped with life-support syste...Deep space is incredibly quiet,but once astronauts leave the station,they must contend with extreme temperatures,fluctuating pressures,and high levels of radiation.Their spacesuits are equipped with life-support systems,which are essential for a safe“walk in space.”On 15 August,the crew of Shenzhou-20 successfully completed their third spacewalk.For this mission,taikonaut Chen Dong wore the extravehicular spacesuit B,which has now been used in 20 spacewalks.With this achievement,the space station has reached the target of“four years and 20 spacewalks.”展开更多
Geothermal exploration and development in North Africa have advanced significantly,driven by the region's rich geothermal resources and rising energy demand.The countries of Mauritania,Morocco,Algeria,Tunisia,Liby...Geothermal exploration and development in North Africa have advanced significantly,driven by the region's rich geothermal resources and rising energy demand.The countries of Mauritania,Morocco,Algeria,Tunisia,Libya,and Egypt are located near tectonic plate boundaries(African and Eurasian plates),giving them substantial geothermal potential.Various exploration activities,including geological surveys and geophysical studies,have been conducted to assess geothermal reservoirs and identify suitable development sites.This article reviews the progress made in geothermal exploration across the region,highlighting the key activities undertaken to evaluate geothermal resources.It also explores how government policies have played a critical role either in fostering or in freezing geothermal development.The different conducted assessments such as analyzing geological structures,hydrothermal systems,and subsurface temperatures lead to identify suitable sites for geothermal development and improve the understanding of subsurface conditions and ongoing projects.Today,some countries in North Africa are positioning themselves to become important players in the global geothermal energy landscape,and with continued investment and concerted efforts,the region has the potential to emerge as a prominent player in the global geothermal energy landscape.展开更多
In response to the current situation of practical teaching and the main problems in the teaching process of cultivating composite talents in the characteristic demonstration software college,this paper analyzes the im...In response to the current situation of practical teaching and the main problems in the teaching process of cultivating composite talents in the characteristic demonstration software college,this paper analyzes the importance of digital reform in practical teaching,introduces the work foundation,main work,reform characteristics,and effects of digital reform in practical teaching of composite talents in Software College of Northeastern University and lays the foundation for future in-depth research,providing reference for the digital reform of practical teaching in related majors of other colleges.展开更多
基金supported by the National Natural Science Foundation of China“Research on Value Chain Structure and Firm Embeddedness of Emerging Industries Driven by Technology Convergence”[Grant number 71704069]the Humanities and Social Science Foundation of China's Ministry of Education“Research on the Formation Mechanism of Dynamic Capability of China's Manufacturing Clusters for Sustainable Eco-innovation”[Grant number 16YJC630125]+1 种基金the Social Science Foundation of Jiangsu Province“Research on Eco-innovation and New Competitive Advantages of Jiangsu Manufacturing Industrial Clusters”[Grant number 17GLB020]the Natural Science Foundation of the Jiangsu Higher Education Institutions“Spatial Pattern Evolution and Influencing Factors of Carbon Emissions Efficiency of Construction Industry in China”[Grant number 17KJB170004]。
文摘The exploration/exploitation perspective is a well-known concept in the strategic management field;however,it has seldom been used to explore and analyze strategy at a national level.This study utilizes this perspective to analyze China's eco-innovation mode in response to climate change.By categorizing eco-innovation into radical and incremental eco-innovation,we examine the relationship between these concepts using Y02 patents as a proxy and panel data from 30 Chinese provinces from 2004 to 2015.The results show that eco-innovation as a whole as well as both radical and incremental innovations are drivers for reducing carbon emissions.Furthermore,contradictory to most previous empirical results related to the complementarity hypothesis,we find a complementary relationship between radical and incremental eco-innovation.These results collectively represent China's unique eco-innovation mode,confirming the assumed diversity of eco-innovation models in different contexts.The results also show the significant positive effects of economic development,urbanization level,industrial structure,and China's opening up on carbon emissions,indicating that economic and social development have not yet been completely dissociated from carbon emissions in China.
文摘In order to tradeoff exploration/exploitation and inspired by cell genetic algorithm a cellshift crossover operator for evolutionary algorithm (EA) is proposed in this paper. The definition domain is divided into n-dimension cubic sub-domains (cell) and each individual locates at an ndimensional cube. Cell-shift crossover first exchanges the cell numbers of the crossover pair if they are in the different cells (exploration) and subsequently shift the first individual from its initial place to the other individual's cell place. If they are already in the same cell heuristic crossover (exploitation) is used. Cell-shift/heuristic crossover adaptively executes exploration/exploitation search with the vary of genetic diversity. The cell-shift EA has excellent performance in terms of efficiency and efficacy on ten usually used optimization benchmarks when comparing with the recent well-known FEP evolutionary algorithm.
文摘From a harmonized structural map at the scale of a portion of SW Burkina Faso (90 × 80 km2), we targeted prospective zones on the basis of structural criteria and structure-geology relationships. The map was constructed from an aeromagnetic image, and the geology was deduced from old geological maps. The procedure involved extracting the magnetic fabric and deducing the deformation gradients, which led to the identification of shear zones. Analysis and interpretation of the structural geometry of the obtained structural pattern led us to target areas of interference between structures or geology-structures interplays, which are conducive to the deposition of metallic elements. The subsequent overlay of known gold prospects and deposits documented in the region revealed the validity of the predefined prospects. This result reinforces the applicability of the methodology as a first-order regional approach to mineral exploration.
文摘In mid-May,good news came from Tajikistan,the country of high mountains.The Tajikistan Bogda Mountain geological exploration and sampling project,which had been dormant for over a decade,achieved a key breakthrough after years of careful research,multi-party collaboration,and optimization of various plans,launching a new round of field exploration and testing work.
基金supported by the Henan Province science and technology research project(Grant No.242102321031)National Natural Science Foundation of China(grant numbers 42207200).
文摘Near-surface geological defects pose a serious threat to human life and infrastructure.Hence,the exploration of geological hazards is essential.Currently,there are various geological hazard exploration methods;however,those require improvements in terms of economic feasibility,convenience,and lateral resolution.To address this,this study examined an extraction method to determine spatial autocorrelation velocity dispersion curves for application in near-surface exploration.
文摘Economic violence is a form of domestic violence that extends beyond physical harm,affecting victims’economic stability and independence.This situation perpetuates gender inequality and also reinforces the cycle of gender-based violence.With definitions of economic violence broadening to encompass a range of coercive and manipulative behaviors-from financial abuse in domestic violence scenarios to the economic harassment faced by stay-at-home moms-understanding this form of exploitation is crucial for crafting effective interventions.This article aims to delve into various facets of economic violence,including its definition,prevalence,and the stark realities it creates for its victims.Following the search of international databases:Social Work Abstracts(EBSCO),Psychology Abstracts,Family and Women Studies Worldwide,Psychiatry Online,Psych INFO(including Psych ARTICLES),PubMed,Wiley,and Scopus,60 peer-reviewed articles that met all inclusion criteria were included in the paper.Our review clarifies that looking forward,the call for a comprehensive understanding of economic violence,enhanced legal frameworks,and the strengthening of supportive networks underscore the multidisciplinary approach required to combat this issue effectively.
文摘On June 3,Scopus,a database owned by Elsevier,released CiteScore 2024 metrics for academic journal evaluation.Both the Chinese and English editions of Petroleum Exploration and Development achieved record highs in the past year,ranking among the top in various categories.The CiteScore of the Chinese edition increased to 9.9 in 2024 from 8.4 in 2023,ranking 13th out of 330 journals in the Earth and Planetary Sciences:Geology category and 2lst out of 239 journals in the Earth and Planetary Sciences:Geotechnical Engineering and Engineering Geology category.
文摘China’s energy resource endowment is characterized by being“poor in oil,scarce in gas,and rich in coal”,a fundamental national condition that determines the uniqueness of China’s energy strategy.At the beginning of the 20th century,foreign experts and scholars generally concluded and claimed that China was an“oil-poor country”lacking the geological conditions for hydrocarbon formation.
文摘At the turn of the new spring,as we bid farewell to 2024 and welcome the Spring Festival of 2025,our entire editorial team of Petroleum Exploration and Development extends heartfelt gratitude and sincere New Year's greetings to our editorial board,experts,authors,readers,and friends from all fields!
文摘Sent out at 1:31am GMT+8 on May 29 by a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Sichuan province,China,Tianwen-2,the second mission of China’s Planetary Exploration Program,correctly entered the transfer trajectory toward an asteroid named 2016HO3 after flying for 18 minutes.Its solar wings unfolded properly,signaling a successful start,and primed for the next stage of its mission.
基金National science and technology signifi cant special(No.2024ZD1003406)Natural Science Research Project of Colleges and Universities in Anhui Province(No.2024AH050374)National Natural Science Foundation of China(Grant No.52274071).
文摘The advancement of intelligent mining in open-pit operations has imposed higher demands on geological transparency,aiming to provide a robust foundation for intelligent drilling and charging.In this study,a linear array of 120 nodal seismometers was deployed along the surfaces of the C8 and C9 platforms at Fenghuang Mountain to investigate cavities within the rock mass and prevent improper intelligent charging.The seismometers were 1 m apart along measurement lines,with a 2-m spacing between lines,and the monitoring time for each line was set at 2 h.This deployment was paired with spatial autocorrelation and station autocorrelation to analyze ambient noise seismic data and image the velocity and structure within the rock mass.The results demonstrate that the locations and sizes of cavities or loose structures can be accurately identified at the prepared excavation site.Compared with traditional geological exploration methods for openpit mines,the approach in this study off ers higher accuracy,greater efficiency,reduced labor intensity,and insensitivity to water conditions.Ambient noise seismic imaging for detecting adverse geological conditions in open-pit mines provides critical insights and references for intelligent mining advancements.
基金the“International Trade”course in the research-based teaching project of undergraduate universities in Henan Province in 2023(project approval number:121)。
文摘This study investigated proactive personality effects on employment preparation and the mediating roles of self-efficacy and career exploration behaviors in this relationship.The study sample comprised 445 university students(68.3%female;aged 20 to 24)from a university in central China.The participants completed measures to assess proactive personality,employment preparation,self-efficacy,and career exploration behaviors.Structural equation modeling analysis results indicated that proactive personality predicted higher employment preparation;Self-efficacy and career exploration behaviors partially mediated this relationship.Specifically,career exploration behaviors had a stronger mediating effect than self-efficacy on the total effect(34.71%vs.28.89%).The findings suggest proactive personality is key to employment preparation through self-belief and willingness to explore the job market.Higher education career counseling and mental health education programs should provide targeted training to promote career exploration by the student’s personal attributes for best match employment preparation.
文摘Bubbles play crucial roles in various fields,including naval and ocean engineering,chemical engineering,and biochemical engineering.Numerous theoretical analyses,numerical simulations,and experimental studies have been conducted to reveal the mysteries of bubble motion and its mechanisms.These efforts have significantly advanced research in bubble dynamics,where theoretical study is an efficient method for bubble motion prediction.Since Lord Rayleigh introduced the theoretical model of single-bubble motion in incompressible fluid in 1917,theoretical studies have been pivotal in understanding bubble dynamics.This study provides a comprehensive review of the development and applicability of theoretical studies in bubble dynamics using typical theoretical bubble models across different periods as a focal point and an overview of bubble theory applications in underwater explosion,marine cavitation,and seismic exploration.This study aims to serve as a reference and catalyst for further advancements in theoretical analysis and practical applications of bubble theory across marine fields.
基金Supported by National Natural Science Foundation of China(Grant No.52405104)Jiangxi Provincial Natural Science Foundation(Grant Nos.20242BAB20249 and 20232BAB204041)Science and Technology Project of Department of Transportation of Jiangxi Province(Grant No.2025QN003).
文摘Autonomous driving technology is constantly developing to a higher level of complex scenes,and there is a growing demand for the utilization of end-to-end data-driven control.However,the end-to-end path tracking process often encounters challenges in learning efficiency and generalization.To address this issue,this paper designs a deep deterministic policy gradient(DDPG)-based reinforcement learning strategy that integrates imitation learning and feedforward exploration in the path following process.In imitation learning,the path tracking control data generated by the model predictive control(MPC)method is used to train an end-to-end steering control model of a deep neural network.Another feedforward exploration behavior is predicted by road curvature and vehicle speed,and adds it and imitation learning to the DDPG reinforcement learning to obtain decision-making experience and action prediction behavior of the path tracking process.In the reinforcement learning process,imitation learning is used to update the pre-training parameters of the actor network,and a feedforward steering technique with random noise is adopted for strategy exploration.In the reward function,a hierarchical progressive reward form and a constrained objective reward function referring to MPC are designed,and the actor-critic network architecture is determined.Finally,the path tracking performance of the designed method is verified by comparing various training results,simulations,and HIL tests.The results show that the designed method can effectively utilize pre-training and feedforward prior experience to obtain optimal path tracking performance of an autonomous vehicle,and has better generalization ability than other methods.This study provides an efficient control scheme for improving the end-to-end control performance of autonomous vehicles.
基金supported by the National Natural Science Foundation of China (No.62202137)the China Postdoctoral Science Foundation (No.2023M730599)the Zhejiang Provincial Natural Science Foundation of China (No.LMS25F020009)。
文摘Embodied visual exploration is critical for building intelligent visual agents. This paper presents the neural exploration with feature-based visual odometry and tracking-failure-reduction policy(Ne OR), a framework for embodied visual exploration that possesses the efficient exploration capabilities of deep reinforcement learning(DRL)-based exploration policies and leverages feature-based visual odometry(VO) for more accurate mapping and positioning results. An improved local policy is also proposed to reduce tracking failures of feature-based VO in weakly textured scenes through a refined multi-discrete action space, keyframe fusion, and an auxiliary task. The experimental results demonstrate that Ne OR has better mapping and positioning accuracy compared to other entirely learning-based exploration frameworks and improves the robustness of feature-based VO by significantly reducing tracking failures in weakly textured scenes.
文摘Renewable energy resources,including geothermal,are crucial for sustainable environmental management and climate change mitigation,offering clean,reliable,and low-emission alternatives to fossil fuels that reduce greenhouse gases and support ecological balance.In this study,geographic information system(GIS)predictive analysis was employed to explore geothermal prospects,promoting environmental sustainability by reducing the dependence on fossil energy resources.Spatial and statistical analysis including the attribute correlation analysis was used to evaluate the relationship between exploration data and geothermal energy resources represented by hot springs.The weighted sum model was then used to develop geothermal predictive maps while the accuracy of prediction was determined using the receiver operating characteristic/area under curve(ROC/AUC)analysis.Based on the attribute correlation analysis,exploration data relating to geological structures,host rock(Asu River Group)and sedimentary contacts were the most critical parameters for mapping geothermal resources.These parameters were characterized by a statistical association of 0.52,0.48,and 0.46 with the known geothermal occurrences.Spatial data integration reveals the central part of the study location as the most prospective zone for geothermal occurrences.This zone occupies 14.76%of the study location.Accuracy assessment using the ROC/AUC analysis suggests an efficiency of 81.5%for the weight sum model.GIS-based multi-criteria analysis improves the identification and evaluation of geothermal resources,leading to better decision-making.
文摘Deep space is incredibly quiet,but once astronauts leave the station,they must contend with extreme temperatures,fluctuating pressures,and high levels of radiation.Their spacesuits are equipped with life-support systems,which are essential for a safe“walk in space.”On 15 August,the crew of Shenzhou-20 successfully completed their third spacewalk.For this mission,taikonaut Chen Dong wore the extravehicular spacesuit B,which has now been used in 20 spacewalks.With this achievement,the space station has reached the target of“four years and 20 spacewalks.”
文摘Geothermal exploration and development in North Africa have advanced significantly,driven by the region's rich geothermal resources and rising energy demand.The countries of Mauritania,Morocco,Algeria,Tunisia,Libya,and Egypt are located near tectonic plate boundaries(African and Eurasian plates),giving them substantial geothermal potential.Various exploration activities,including geological surveys and geophysical studies,have been conducted to assess geothermal reservoirs and identify suitable development sites.This article reviews the progress made in geothermal exploration across the region,highlighting the key activities undertaken to evaluate geothermal resources.It also explores how government policies have played a critical role either in fostering or in freezing geothermal development.The different conducted assessments such as analyzing geological structures,hydrothermal systems,and subsurface temperatures lead to identify suitable sites for geothermal development and improve the understanding of subsurface conditions and ongoing projects.Today,some countries in North Africa are positioning themselves to become important players in the global geothermal energy landscape,and with continued investment and concerted efforts,the region has the potential to emerge as a prominent player in the global geothermal energy landscape.
文摘In response to the current situation of practical teaching and the main problems in the teaching process of cultivating composite talents in the characteristic demonstration software college,this paper analyzes the importance of digital reform in practical teaching,introduces the work foundation,main work,reform characteristics,and effects of digital reform in practical teaching of composite talents in Software College of Northeastern University and lays the foundation for future in-depth research,providing reference for the digital reform of practical teaching in related majors of other colleges.