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Impact toughness,crack initiation and propagation mechanism of Ti6422 alloy with multi-level lamellar microstructure
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作者 Jie Shen Zhihao Zhang Jianxin Xie 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期595-609,共15页
The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.... The influence of different solution and aging conditions on the microstructure,impact toughness,and crack initiation and propagation mechanisms of the novel α+β titanium alloy Ti6422 was systematically investigated.By adjusting the furnace cooling time after solution treatment and the aging temperature,Ti6422 alloy samples were developed with a multi-level lamellar microstructure,in-cluding microscaleαcolonies and α_(p) lamellae,as well as nanoscale α_(s) phases.Extending the furnace cooling time after solution treatment at 920℃ for 1 h from 240 to 540 min,followed by aging at 600℃ for 6 h,increased the α_(p) lamella content,reduced the α_(s) phase content,expanded theαcolonies and α_(p) lamellae size,and improved the impact toughness from 22.7 to 53.8 J/cm^(2).Additionally,under the same solution treatment,raising the aging temperature from 500 to 700℃ resulted in a decrease in the α_(s) phase content and a growth in the thickness of the α_(p) lamella and α_(s) phase.The impact toughness increased significantly with these changes.Samples with high α_(p) lamellae content or large α_(s) phase size exhibited high crack initiation and propagation energies.Impact deformation caused severe kinking of the α_(p) lamellae in crack initiation and propagation areas,leading to a uniform and high-density kernel average misorientation(KAM)distribu-tion,enhancing plastic deformation coordination and uniformity.Moreover,the multidirectional arrangement of coarserαcolonies and α_(p) lamellae continuously deflect the crack propagation direction,inhibiting crack propagation. 展开更多
关键词 novel titanium alloy multi-level lamellar microstructure impact toughness crack initiation and propagation
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A survey of five first-level hospital ethics committees in Urumqi,China
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作者 Jian LIU Jie SHEN Pei-zhen LIU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第6期541-548,共8页
This paper presents the results from a survey of first-level hospitals in Urumqi,China.The survey had two parts:the first part was aimed at understanding the operation of the ethics committees of first-level hospitals... This paper presents the results from a survey of first-level hospitals in Urumqi,China.The survey had two parts:the first part was aimed at understanding the operation of the ethics committees of first-level hospitals,including the process for electing members and the variety of members' backgrounds.Information was also gathered about the establishment of criteria,operational rules and regulations,and standard operational procedures.The aim of the second part was to investigate the level of understanding among technicians and doctors about the function of the ethics committees.This paper identifies and analyzes some deficiencies found in the operation of hospital ethics committees,offers some constructive suggestions for improvement,and promotes the role of the Xinjiang Uygur autonomous region hospital ethics committees. 展开更多
关键词 First-level hospital Ethics committee Xinjiang Urumqi
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Election Procedure for Rural Two Committees
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作者 Lin ZENG Wenbin SU +6 位作者 Chaozhong ZHANG Shunsheng LU Yunfei SONG Guotian YANG Mingshan LIAO Zhenzhao SAI Yan LIU 《Asian Agricultural Research》 2017年第5期48-51,55,共5页
In order to further strengthen the construction and improvement of villager autonomy system with democratic election,democratic decision making,democratic management,and democratic supervision of rural two committees ... In order to further strengthen the construction and improvement of villager autonomy system with democratic election,democratic decision making,democratic management,and democratic supervision of rural two committees with Chinese characteristics,experience of work team of Longyang District Agricultural Technology Extension Station dispatched to villager committees( or offices) and their guidance on election of rural two committees in 2007-2016 were used,and exploration was made for election of rural two committees from the third to the sixth committees. It summarized achievements and main problems in election of rural two committees and came up with pertinent recommendations.The results of this study are expected to provide certain reference for theory and practice of future villager autonomy. 展开更多
关键词 Rural two committees Election procedure Villager committee
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Board Independence and Internal Committees in the BRICs
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作者 Daniela M. Salvioni Luisa Bosetti Alex Almici 《Chinese Business Review》 2013年第8期521-539,共19页
To be successful in global markets, companies from the emerging countries need the approval of foreign investors and other stakeholders. In this regard, Brazil, Russia, India, and China (BRIC) have progressively str... To be successful in global markets, companies from the emerging countries need the approval of foreign investors and other stakeholders. In this regard, Brazil, Russia, India, and China (BRIC) have progressively strengthened their corporate governance rules to help their companies overcome the competitors from the old industrialized countries. Directors' non-executive qualification, independence, and professional expertise represent basic requirements for effective corporate governance, so they should be carefully considered to guarantee a proper board composition and an adequate establishment of internal committees in listed companies. The paper intends to compare the legislative and regulatory frameworks adopted by the four countries; then it aims at answering to the following research questions by means of an empirical investigation: Have BRIC companies appointed non-executive and independent board members? What do BRIC companies do in order to assure an effective participation of non-executive and independent board members to corporate governance activities? Have BRIC companies established internal committees? The research examines the appointment of non-executive directors and independent directors to the boards of 100 BRIC leading firms, as well as their involvement in internal committees focused on matters requiring motivated and impartial opinions. Although the laws and recommendations seem to favor a general convergence of corporate governance principles among the four BRIC and towards the international best practices, some differences and peculiarities emerge from a firm-level perspective. Indeed, the Indian and the Chinese companies analyzed appear more inclined than the Brazilian and the Russian ones to reassure their international stakeholders about board independence and effective committees. 展开更多
关键词 corporate governance GLOBALIZATION CONVERGENCE BRICS INDEPENDENCE board committees
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Audit Committees: How They Affect Financial Reporting in Nigerian Companies
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作者 Abdulkadir Madawaki Noor Afza Amran 《Journal of Modern Accounting and Auditing》 2013年第8期1070-1080,共11页
This study examines whether audit committees are associated with improved financial reporting quality for a sample of Nigerian listed companies prior to and after a corporate governance code mandated new regulations f... This study examines whether audit committees are associated with improved financial reporting quality for a sample of Nigerian listed companies prior to and after a corporate governance code mandated new regulations for audit committees in 2003. Using a sample of 70 companies listed on the Nigerian Stock Exchange, this study uses archival data in the form of companies' annual reports to measure the association between audit committees and improved financial reporting quality. Dechew and Dichev (2002)'s model was used to measure earnings as a proxy for financial reporting quality. The results indicate that formation of audit committees was positively associated with improved financial reporting quality. It was also found that audit committees having an independent chair and audit committee expertise were positively associated with financial reporting quality. Other audit committee characteristics examined were found to be insignificantly related to financial reporting quality. 展开更多
关键词 audit committees financial reporting quality Nigerian listed companies
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Effectiveness of Supervisory Boards in Coordination With Audit Committees in China
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作者 Pao-Chen Lee 《Chinese Business Review》 2012年第12期1250-1263,共14页
China's supervisory mechanism is peculiar in that it integrated the supervisory board (SB) of the German corporate governance (CG) model in 1993, and has simultaneously adopted the audit committee (AC) of the A... China's supervisory mechanism is peculiar in that it integrated the supervisory board (SB) of the German corporate governance (CG) model in 1993, and has simultaneously adopted the audit committee (AC) of the Anglo-American model since 2002. This paper aims to reveal the effectiveness of SBs in coordination with ACs in China. The regulations for Anglo-American and Chinese systems are compared and further evidence is provided through interviewing two governors of all listed companies in the SSE and of 79 investment corporations in Hangzhou. Both statements indicate that China still faces difficulties and problems in meeting the two indexes of independence and expertise of supervision to give effective supervisory functions. Both opinions differed in terms of the co-ordination of SBs and ACs in the future. The evidence presented forms a basis for proposals of how key characteristics of effectiveness and co-ordination can be improved to make supervisory functions in China more effective. 展开更多
关键词 EFFECTIVENESS audit committee (AC) supervisory board (SB) corporate govemance (CG)
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National Standardization Technical Committees & Subcommittees
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《China Standardization》 2005年第1期47-48,共2页
关键词 SCI TC National Standardization Technical committees Subcommittees
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A Multi-Level Semantic Constraint Approach for Highway Tunnel Scene Twin Modeling 被引量:2
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作者 LI Yufei XIE Yakun +3 位作者 CHEN Mingzhen ZHAO Yaoji TU Jiaxing HU Ya 《Journal of Geodesy and Geoinformation Science》 2025年第2期37-56,共20页
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge... As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes. 展开更多
关键词 highway tunnel twin modeling multi-level semantic constraints tunnel vehicles multidimensional modeling
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Research on Multi-Level Automatic Filling Optimization Design Method for Layered Cross-Sectional Layout of Umbilical 被引量:1
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作者 YIN Xu FAN Zhi-rui +4 位作者 CAO Dong-hui LIU Yu-jie LI Meng-shu YAN Jun YANG Zhi-xun 《China Ocean Engineering》 2025年第5期891-903,共13页
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple... The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections. 展开更多
关键词 UMBILICAL cross-sectional layout multi-level filling layered layout optimization design
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Three National Standardizetion Technical Committees Authorized By SAC
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《China Standardization》 2005年第2期14-14,共1页
In December, 2004, the Standardization Administration of China (SAC) has approved the establishments of three National Standardization Technical Committees. They are the National Standardization Technical Committees f... In December, 2004, the Standardization Administration of China (SAC) has approved the establishments of three National Standardization Technical Committees. They are the National Standardization Technical Committees for Environmental Protection Products (SAC/TC275), for Safety Management of Agricultural Transgenic Biology (SAC/TC276) and for Testing of New Varieties of Plant (SAC/TC277).The National Standardization Technical Committee for Environmental Protection Products is responsible for the development and revision of national standards in the following fields: 展开更多
关键词 Three National Standardization Technical committees Authorized By SAC
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CAS is to organize the establishment of new national professional standardization technical committees, subcommittees & working groups under the commissioning of SAC
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《China Standardization》 2006年第2期37-,共1页
关键词 SAC subcommittees CAS is to organize the establishment of new national professional standardization technical committees working groups under the commissioning of SAC
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MEMBERSHIP OF THE 1996 CAS PRESIDIUM & STANDING COMMITTEES OF THE CAS ACADEMIC DIVISIONS
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《Bulletin of the Chinese Academy of Sciences》 1996年第3期192-194,共3页
Chen Nengkuan Liang Xiaotian Ni Jiazan Wang Yuan Zheng
关键词 CAS CHEN MEMBERSHIP OF THE 1996 CAS PRESIDIUM STANDING committees OF THE CAS ACADEMIC DIVISIONS WANG
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Analysis of New Model of "Rule by Three Committees" and Discussion on Construction of Villagers' Self-governing Organizations in China
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作者 YANG Cheng ZHANG Lu-ping 《Asian Agricultural Research》 2011年第7期98-102,共5页
This paper introduces the operation model of "rule by three committees", including the members of "three committees", functional constitution of "three committees", and relationship betwe... This paper introduces the operation model of "rule by three committees", including the members of "three committees", functional constitution of "three committees", and relationship between restriction and coordination of "three committees". By referring to the villagers' self-governing system in China, and the relevant provisions in Constitution and Village Committee Organization Law, we take into account the legitimacy of "rule by three committees". In terms of the details of system design, we perfect the new model of "rule by three committees" as follows: make the conditions of holding office stringent and ensure the quality requirements of members of "three committees"; standardize the procedures of election, and guarantee the equitable election of members of "three committees"; perfect dismissal procedure, and strengthen the supervision on members of "three committees". 展开更多
关键词 Villagers'self-governing Villagers'self-governing organizations 'Rule by three committees' China
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Analysis of the Election of Village Committees: A Case in Shanxi Province
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作者 XIAN KAILIN SHI RUI 《The Journal of Human Rights》 2013年第3期36-39,共4页
The report to the 18th National Congress of the Communist Party of China (CPC) called for improving the grassroots autonomy mechanism led by grassroots Party organizations; paying more attention to enriching democra... The report to the 18th National Congress of the Communist Party of China (CPC) called for improving the grassroots autonomy mechanism led by grassroots Party organizations; paying more attention to enriching democracy, improving the democratic system to ensure people's democratic elections, democratic decision-making, democratic management and democratic supervision; 展开更多
关键词 Analysis of the Election of Village committees A Case in Shanxi Province
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MEMBERSHIP OF THE CAS PRESIDIUM AND STANDING COMMITTEES OF THE CAS ACADEMIC DIVISIONS
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《Bulletin of the Chinese Academy of Sciences》 1995年第3期222-225,共4页
关键词 CAS MEMBERSHIP OF THE CAS PRESIDIUM AND STANDING committees OF THE CAS ACADEMIC DIVISIONS CHEN ZHANG
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CAS sets up committee on smart elderly care facilities
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作者 Fang Luofan 《China Standardization》 2025年第6期26-26,共1页
This year’s WSD draws attention to par tnerships for the SDGs.Therefore,China Association for Standardization(CAS)held the inauguration ceremony of the professional committee on smart elderly care facilities on Octob... This year’s WSD draws attention to par tnerships for the SDGs.Therefore,China Association for Standardization(CAS)held the inauguration ceremony of the professional committee on smart elderly care facilities on October 11 in Shenzhen. 展开更多
关键词 smart elderly care facilities partnerships sdgs professional committee inauguration ceremony par tnerships
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Multi-relation spatiotemporal graph residual network model with multi-level feature attention:A novel approach for landslide displacement prediction
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作者 Ziqian Wang Xiangwei Fang +3 位作者 Wengang Zhang Xuanming Ding Luqi Wang Chao Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4211-4226,共16页
Accurate prediction of landslide displacement is crucial for effective early warning of landslide disasters.While most existing prediction methods focus on time-series forecasting for individual monitoring points,ther... Accurate prediction of landslide displacement is crucial for effective early warning of landslide disasters.While most existing prediction methods focus on time-series forecasting for individual monitoring points,there is limited research on the spatiotemporal characteristics of landslide deformation.This paper proposes a novel Multi-Relation Spatiotemporal Graph Residual Network with Multi-Level Feature Attention(MFA-MRSTGRN)that effectively improves the prediction performance of landslide displacement through spatiotemporal fusion.This model integrates internal seepage factors as data feature enhancements with external triggering factors,allowing for accurate capture of the complex spatiotemporal characteristics of landslide displacement and the construction of a multi-source heterogeneous dataset.The MFA-MRSTGRN model incorporates dynamic graph theory and four key modules:multilevel feature attention,temporal-residual decomposition,spatial multi-relational graph convolution,and spatiotemporal fusion prediction.This comprehensive approach enables the efficient analyses of multi-source heterogeneous datasets,facilitating adaptive exploration of the evolving multi-relational,multi-dimensional spatiotemporal complexities in landslides.When applying this model to predict the displacement of the Liangshuijing landslide,we demonstrate that the MFA-MRSTGRN model surpasses traditional models,such as random forest(RF),long short-term memory(LSTM),and spatial temporal graph convolutional networks(ST-GCN)models in terms of various evaluation metrics including mean absolute error(MAE=1.27 mm),root mean square error(RMSE=1.49 mm),mean absolute percentage error(MAPE=0.026),and R-squared(R^(2)=0.88).Furthermore,feature ablation experiments indicate that incorporating internal seepage factors improves the predictive performance of landslide displacement models.This research provides an advanced and reliable method for landslide displacement prediction. 展开更多
关键词 Landslide displacement prediction Spatiotemporal fusion Dynamic graph Data feature enhancement multi-level feature attention
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Implementation of Villagers Autonomy on Fast Lane——In commemoration of the fifth anniversary of the promulgation and implementation of the Organic Law of the Villagers Committees
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作者 WANG JINHUA 《The Journal of Human Rights》 2004年第1期16-17,共2页
It is already five years since the 10-year-old experimental law on the organization of villagers committees adopted in November 1987 by the Standing Committee of the National People’s Congress was made permanent, end... It is already five years since the 10-year-old experimental law on the organization of villagers committees adopted in November 1987 by the Standing Committee of the National People’s Congress was made permanent, ending an intense political debate about how much independence villagers committees should be given to manage village affairs and to what extent villagers should be allowed to choose their leaders. It is five years in which the implementation of villagers autonomy as defined by the law proceeded the fastest and the achievements were the most fruitful. Local laws Over the past five years, all places 展开更多
关键词 In commemoration of the fifth anniversary of the promulgation and implementation of the Organic Law of the Villagers committees Implementation of Villagers Autonomy on Fast Lane
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A robust method for large-scale route optimization on lunar surface utilizing a multi-level map model
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作者 Yutong JIA Shengnan ZHANG +5 位作者 Bin LIU Kaichang DI Bin XIE Jing NAN Chenxu ZHAO Gang WAN 《Chinese Journal of Aeronautics》 2025年第3期134-150,共17页
As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could ra... As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could range from kilometers to tens of kilometers, and even hundreds and thousands of kilometers. Therefore, it is crucial to develop effective long-range path planning for lunar rovers to meet the demands of lunar patrol exploration. This paper presents a hierarchical map model path planning method that utilizes the existing high-resolution images, digital elevation models and mineral abundance maps. The objective is to address the issue of the construction of lunar rover travel costs in the absence of large-scale, high-resolution digital elevation models. This method models the reference and semantic layers using the middle- and low-resolution remote sensing data. The multi-scale obstacles on the lunar surface are extracted by combining the deep learning algorithm on the high-resolution image, and the obstacle avoidance layer is modeled. A two-stage exploratory path planning decision is employed for long-distance driving path planning on a global–local scale. The proposed method analyzes the long-distance accessibility of various areas of scientific significance, such as Rima Bode. A high-precision digital elevation model is created using stereo images to validate the method. Based on the findings, it can be observed that the entire route spans a distance of 930.32 km. The route demonstrates an impressive ability to avoid meter-level impact craters and linear structures while maintaining an average slope of less than 8°. This paper explores scientific research by traversing at least seven basalt units, uncovering the secrets of lunar volcanic activities, and establishing ‘golden spike’ reference points for lunar stratigraphy. The final result of path planning can serve as a valuable reference for the design, mission demonstration, and subsequent project implementation of the new manned lunar rover. 展开更多
关键词 Crewed lunar exploration Long-range path planningi multi-level map Deep learning Volcanic activities
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