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Gold Sun:Actively planning for the Vietnamese market
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作者 Zhong Mengxia 《China Textile》 2024年第2期9-9,共1页
Jiangsu Gold Sun is a textile enterprise mainly manufacturing home textile fabrics integrated with R&D,sales and service.Gold Sun has won wide recognition and good reputation in the domestic and international home... Jiangsu Gold Sun is a textile enterprise mainly manufacturing home textile fabrics integrated with R&D,sales and service.Gold Sun has won wide recognition and good reputation in the domestic and international home textile industry through its persistent brand development.In 2023,Gold Sun has been steadily moving forward,continuously innovating and actively tackling market changes,showing its strong competitiveness.This year,Gold Sun continues to explore new areas,and the company participated in the first VITATT 2024 on Feburary 28th. 展开更多
关键词 market CONTINUE service
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The role of forest culture in green construction and management of forest parks:merging knowledge-attitude-practice and theory of planned behavior 被引量:1
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作者 Yao Xu Zhiguang Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期841-852,共12页
As a cultural concept refl ecting the relationship between humans and forests,forest culture plays an active role in sustainable forest management.Forest parks provide a wide range of ecosystem services essential for ... As a cultural concept refl ecting the relationship between humans and forests,forest culture plays an active role in sustainable forest management.Forest parks provide a wide range of ecosystem services essential for the sustainable development of society,and the relationships between forest culture,green construction and management of forest parks have practical signifi cance.This study aimed to understand the interaction and process of forest culture infl uencing green construction and management in forest parks with the models Knowledge-Attitude-Practice(KAP)and Theory of Planned Behavior(TPB)by proposing a theoretical model.Four hypotheses were tested using data collected from 193 forest park employees in Heilongjiang Province,China.Our results show that forest culture had a signifi cant infl uence on green construction and forest management.In addition,subjective norm and perceived behavioral control directly impacted behavior in green construction and management of the forest park,whereas attitude did not have an impact.Subjective norm had a direct eff ect on attitude.Results between constructs show that forest culture had an indirect eff ect on planning and construction,and on ecological and economic management.Consequently,it supported three of four hypotheses within the proposed model in determining the infl uence of forest culture on green construction and management. 展开更多
关键词 Forest parks Forest culture Green construction and management Knowledge-attitudepractice Theory of planned behavior
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Design of a Social Marketing Plan on Salt Reduction for the Control and Treatment of Noncommunicable Diseases in Costa Rica
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作者 Adriana Blanco-Metzler Hilda Patricia Nuñez-Rivas +3 位作者 Marlene Roselló-Araya Karol Madriz-Morales Karla Benavides-Aguilar Marco Castro-Araya 《Food and Nutrition Sciences》 2023年第11期1057-1077,共21页
High blood pressure and other non-communicable diseases associated with excessive salt/sodium consumption represent a major challenge to the health of the world’s population. Consumption is a human behavior that is u... High blood pressure and other non-communicable diseases associated with excessive salt/sodium consumption represent a major challenge to the health of the world’s population. Consumption is a human behavior that is usually influenced by significant factors, internal and external to people. The design of a national social marketing intervention is described. The whole process was developed by a national interdisciplinary team over the course of a decade (2011-2022). Its purpose is to promote changes in this behavior, through gradual reduction of salt/sodium consumption in the target populations of Costa Rica, for the prevention and control of associated diseases. The process includes four phases: research, situation analysis, creation of a proposal for the social marketing strategy, and implementation and evaluation. Last phase was not developed by the research team. The main inputs used to design this intervention were the data generated in three qualitative researchers carried out by the national work team and the social marketing regional plan for salt consumption reduction in Latin America. By analyzing these research data, marketing mix components were determined for designing the intervention. The marketing strategy is promotional and is based on encouraging a natural diet with less sodium using natural seasonings and adding less discretional salt and industrialized products high in sodium, in the preparation of food and dishes. The primary key audience is the mother of the school-aged child, and the secondary is the adult caregivers of this child. It is expected that in the short term, health promoters from different government and non-state sectors will contribute to the implementation of the national social marketing plan, to achieve, in the medium or long term, a consumption that approaches five grams of salt per person per day. This plan is a country initiative to position the value of a natural diet with less sodium and to contribute to the prevention and treatment of HT and NCD associated diseases. 展开更多
关键词 SALT Social marketing Behavior Change Noncommunicable Diseases SODIUM
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Discussion on the Planning of a Remaining Market in the New Urban Area under the Background of Urbanization: A case study of Xin’an Grand Market of Qingdao
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作者 LIU Zihan LI Daoyong YANG Peizhe 《Journal of Landscape Research》 2023年第6期27-30,共4页
Chinese markets play an important social role in the long history and are important places for currency circulation,human communication and cultural collision.However,with the acceleration of urbanization,market civil... Chinese markets play an important social role in the long history and are important places for currency circulation,human communication and cultural collision.However,with the acceleration of urbanization,market civilization has gradually faded.In this study,the current situation of a remaining market in Qingdao Development Zone was surveyed,and the problems of the market were discussed.Meanwhile,the reasons for the formation and survival of the market were analyzed,and some strategies to transform the market were put forward to find a way out for the development of the same type of markets in China. 展开更多
关键词 URBANIZATION market A new city Xin’an
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Creating the Role of Rural Teachers as New Rural Sages under the Background of Rural Revitalization Based on Organizational Change and Planned Happenstance Theories
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作者 LIN Jiangfeng YANG Shuai SHAN Yingyu 《Journal of Landscape Research》 2023年第6期65-68,72,共5页
In the context of rural revitalization,people are re-examining the issue of creating the role of teachers as“new rural sages”.However,most of previous studies ignored the school organizational change in the process ... In the context of rural revitalization,people are re-examining the issue of creating the role of teachers as“new rural sages”.However,most of previous studies ignored the school organizational change in the process of reform.The planned happenstance suggests that teachers should maintain a positive mindset about the eventualities in their careers.Based on the organizational change theory,this paper gave some advice to help teachers in playing a role of new rural sages:①rooting in local culture and enhancing teachers’sense of belonging,②providing compensation for teachers in a targeted way,and③providing a comprehensive and objective evaluation mechanism for ensuring teachers’participation in social governance. 展开更多
关键词 Rural teacher School organizational reform planned happenstance theory New rural sage
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Exploration moving beyond medical facility walls:opportunities,challenges and attitudes of midwives towards planned homebirth:a qualitative
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作者 Thuraya Ibrahim Ahmad Fallatah Grace Mcfarlane Lindsay 《Nursing Communications》 2023年第18期1-8,共8页
Background:The establishment of Saudi Vision 2030 has led to a shift from obstetric care to midwifery-led care in maternity care,giving rise to planned home birth(PHB).This study may enable midwives to carry out PHB a... Background:The establishment of Saudi Vision 2030 has led to a shift from obstetric care to midwifery-led care in maternity care,giving rise to planned home birth(PHB).This study may enable midwives to carry out PHB and achieve the goals of the Saudi health vision.The general aim is to explore Saudi midwives’attitudes towards the PHB,opportunities and challenges associated with PHB implementation in Saudi Arabia.Methods:We employed a qualitative study design and conducted interviews using open-ended questions with 19 Saudi midwives recruited from thirteen health regions.Thematic analysis was manually performed to analyze the qualitative data.Results:Thematic analysis revealed seven major themes:midwives as care providers in PHB,health institutions,academic institutions,national policy for PHB,Women’s health status,socio-economic and physical environment suitability,and maternal and neonatal health outcomes.However,Saudi midwives would exhibit a favorable attitude towards PHB if decision-makers from the Ministry of Health and the Ministry of Education addressed the challenges and promoted opportunities for providers,organizations,and the population.Conclusion:The findings of the thematic analysis shed light on several positive aspects,including job opportunities and high financial incomes for midwives.However,they also revealed challenges such as a shortage of midwifery staff,a scarcity of midwifery academic programs,and an ineffective administrative support system for midwives.Integrating both sets of findings enhances the understanding of the challenges and opportunities of planned home birth in Saudi Arabia from various perspectives,capturing the breadth and depth of the obtained data. 展开更多
关键词 planned home birth thematic analysis maternal services midwife Saudi Arabia
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Optimal search path planning of UUV in battlefeld ambush scene
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作者 Wei Feng Yan Ma +3 位作者 Heng Li Haixiao Liu Xiangyao Meng Mo Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期541-552,共12页
Aiming at the practical application of Unmanned Underwater Vehicle(UUV)in underwater combat,this paper proposes a battlefield ambush scene with UUV considering ocean current.Firstly,by establishing these mathematical ... Aiming at the practical application of Unmanned Underwater Vehicle(UUV)in underwater combat,this paper proposes a battlefield ambush scene with UUV considering ocean current.Firstly,by establishing these mathematical models of ocean current environment,target movement,and sonar detection,the probability calculation methods of single UUV searching target and multiple UUV cooperatively searching target are given respectively.Then,based on the Hybrid Quantum-behaved Particle Swarm Optimization(HQPSO)algorithm,the path with the highest target search probability is found.Finally,through simulation calculations,the influence of different UUV parameters and target parameters on the target search probability is analyzed,and the minimum number of UUVs that need to be deployed to complete the ambush task is demonstrated,and the optimal search path scheme is obtained.The method proposed in this paper provides a theoretical basis for the practical application of UUV in the future combat. 展开更多
关键词 Battlefield ambush Optimal search path planning UUV path planning Probability of cooperative search
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Impact of Sharing Marketing on Marketing Willingness of Employees in Internet Decoration Industry
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作者 Zhongxin LI 《Asian Agricultural Research》 2024年第1期10-13,共4页
With the development of information technology,sharing marketing,as an innovative marketing method,plays an important role in promoting the marketing willingness and enthusiasm of employees in the Internet decoration ... With the development of information technology,sharing marketing,as an innovative marketing method,plays an important role in promoting the marketing willingness and enthusiasm of employees in the Internet decoration industry.Based on the data obtained from the ques-tionnaire survey,this paper makes an empirical analysis of the impact of the economic value,social value,perceived ease of use,perceived convenience,enabling conditions and subjective norms of sharing marketing on the marketing willingness of employees in the Internet decoration industry.The results showed that the questionnaire had good internal consistency and construct validity.Through empirical analysis,it can be found that the economic value,social value,perceived ease of use,perceived convenience,enabling conditions and subjective norms of sharing marketing have a significant positive impact on employees'marketing willingness. 展开更多
关键词 marketING Sharing marketing Internet decoration marketing willingness
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Stochastic programming based coordinated expansion planning of generation,transmission,demand side resources,and energy storage considering the DC transmission system
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作者 Liang Lu Mingkui Wei +4 位作者 Yuxuan Tao Qing Wang Yuxiao Yang Chuan He Haonan Zhang 《Global Energy Interconnection》 EI CSCD 2024年第1期25-37,共13页
With the increasing penetration of wind and solar energies,the accompanying uncertainty that propagates in the system places higher requirements on the expansion planning of power systems.A source-grid-load-storage co... With the increasing penetration of wind and solar energies,the accompanying uncertainty that propagates in the system places higher requirements on the expansion planning of power systems.A source-grid-load-storage coordinated expansion planning model based on stochastic programming was proposed to suppress the impact of wind and solar energy fluctuations.Multiple types of system components,including demand response service entities,converter stations,DC transmission systems,cascade hydropower stations,and other traditional components,have been extensively modeled.Moreover,energy storage systems are considered to improve the accommodation level of renewable energy and alleviate the influence of intermittence.Demand-response service entities from the load side are used to reduce and move the demand during peak load periods.The uncertainties in wind,solar energy,and loads were simulated using stochastic programming.Finally,the effectiveness of the proposed model is verified through numerical simulations. 展开更多
关键词 Hydro-wind-solar complementary Expansion planning Demand response Energy storage system Source-network-demand-storage coordination
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A Reverse Path Planning Approach for Enhanced Performance of Multi-Degree-of-Freedom Industrial Manipulators
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作者 Zhiwei Lin Hui Wang +3 位作者 Tianding Chen Yingtao Jiang Jianmei Jiang Yingpin Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1357-1379,共23页
In the domain of autonomous industrial manipulators,precise positioning and appropriate posture selection in path planning are pivotal for tasks involving obstacle avoidance,such as handling,heat sealing,and stacking.... In the domain of autonomous industrial manipulators,precise positioning and appropriate posture selection in path planning are pivotal for tasks involving obstacle avoidance,such as handling,heat sealing,and stacking.While Multi-Degree-of-Freedom(MDOF)manipulators offer kinematic redundancy,aiding in the derivation of optimal inverse kinematic solutions to meet position and posture requisites,their path planning entails intricate multiobjective optimization,encompassing path,posture,and joint motion optimization.Achieving satisfactory results in practical scenarios remains challenging.In response,this study introduces a novel Reverse Path Planning(RPP)methodology tailored for industrial manipulators.The approach commences by conceptualizing the manipulator’s end-effector as an agent within a reinforcement learning(RL)framework,wherein the state space,action set,and reward function are precisely defined to expedite the search for an initial collision-free path.To enhance convergence speed,the Q-learning algorithm in RL is augmented with Dyna-Q.Additionally,we formulate the cylindrical bounding box of the manipulator based on its Denavit-Hartenberg(DH)parameters and propose a swift collision detection technique.Furthermore,the motion performance of the end-effector is refined through a bidirectional search,and joint weighting coefficients are introduced to mitigate motion in high-power joints.The efficacy of the proposed RPP methodology is rigorously examined through extensive simulations conducted on a six-degree-of-freedom(6-DOF)manipulator encountering two distinct obstacle configurations and target positions.Experimental results substantiate that the RPP method adeptly orchestrates the computation of the shortest collision-free path while adhering to specific posture constraints at the target point.Moreover,itminimizes both posture angle deviations and joint motion,showcasing its prowess in enhancing the operational performance of MDOF industrial manipulators. 展开更多
关键词 Reverse path planning Dyna-Q bidirectional search posture angle joint motion
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A Planning Method for Operational Test of UAV Swarm Based on Mission Reliability
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作者 Jingyu Wang Ping Jiang Jianjun Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1889-1918,共30页
The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the... The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the high cost and long duration of operational tests,it is essential to plan the test in advance.To solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission reliability.Therefore,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test plans.This study first constructs a mission reliability model for the UAV swarm in the combat stage.Then,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability model.Finally,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the model.The optimal plans considering both reliability and cost are obtained.The proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning. 展开更多
关键词 UAV swarm PMS MOQPSO BDD mission reliability operational test planning
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Correlates of Mistimed Pregnancy and Unmet Need for Family Planning among Women of Reproductive Age in Sandema, Ghana
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作者 Elvis Junior Dun-Dery Elijah Yendaw +2 位作者 Frederick Dun-Dery Lawrence Bagrmwin Menaal Kaushal 《Advances in Reproductive Sciences》 CAS 2024年第2期125-140,共16页
Background: Globally, an estimated 80 million unintended pregnancies comprising both mistimed and unwanted pregnancies are recorded yearly. Yet only half of the women at risk of mistimed pregnancy use contraceptives. ... Background: Globally, an estimated 80 million unintended pregnancies comprising both mistimed and unwanted pregnancies are recorded yearly. Yet only half of the women at risk of mistimed pregnancy use contraceptives. In developing countries, over 100 million females have unmet need, and national surveys in Ghana indicate 23% unmet need rate. Methods: Using a cross-sectional community-based approach, a sample size of 300 women of reproductive age were selected using multi-step cluster sampling techniques. The study was quantitative, using structured interviewer-administered questionnaires. Results: Two-third (66%) of the women in reproductive age still had unmet need, 71% were currently pregnant, and more than a third (36%) confirmed ever having a mistimed pregnancy. Fifty-three percent (53%) of the women confirmed never communicating with their partners on family planning issues, a little below half (45%) took their own health care decisions. Seventy nine percent (79%) ever received family planning services from a health professional. Factors related to unmet needs included mistimed pregnancy, level of education, preferred birth/pregnancy interval, communication between partners and the autonomy to spend self-earnings. Conclusion: Considering that high rates of unmet need results in mistimed pregnancy, improved policies around the influence of unmet need on mistimed pregnancies are needed. 展开更多
关键词 CONTRACEPTION Family planning Mistimed Pregnancy Ghana Unintended Pregnancy
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Ground threat prediction-based path planning of unmanned autonomous helicopter using hybrid enhanced artificial bee colony algorithm
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作者 Zengliang Han Mou Chen +1 位作者 Haojie Zhu Qingxian Wu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期1-22,共22页
Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning system.Aiming to reduce the influence of non-complete ground threat information on UAH path planning,a gro... Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning system.Aiming to reduce the influence of non-complete ground threat information on UAH path planning,a ground threat prediction-based path planning method is proposed based on artificial bee colony(ABC)algorithm by collaborative thinking strategy.Firstly,a dynamic threat distribution probability model is developed based on the characteristics of typical ground threats.The dynamic no-fly zone of the UAH is simulated and established by calculating the distribution probability of ground threats in real time.Then,a dynamic path planning method for UAH is designed in complex environment based on the real-time prediction of ground threats.By adding the collision warning mechanism to the path planning model,the flight path could be dynamically adjusted according to changing no-fly zones.Furthermore,a hybrid enhanced ABC algorithm is proposed based on collaborative thinking strategy.The proposed algorithm applies the leader-member thinking mechanism to guide the direction of population evolution,and reduces the negative impact of local optimal solutions caused by collaborative learning update strategy,which makes the optimization performance of ABC algorithm more controllable and efficient.Finally,simulation results verify the feasibility and effectiveness of the proposed ground threat prediction path planning method. 展开更多
关键词 UAH Path planning Ground threat prediction Hybrid enhanced Collaborative thinking
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Trajectory planning for multi-robot coordinated towing system based on stability
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作者 赵志刚 ZHAO Xiangtang +2 位作者 WEI Qizhe SU Cheng MENG Jiadong 《High Technology Letters》 EI CAS 2024年第1期43-51,共9页
Given the unconstrained characteristics of the multi-robot coordinated towing system,the rope can only provide a unidirectional constraint force to the suspended object,which leads to the weak ability of the system to... Given the unconstrained characteristics of the multi-robot coordinated towing system,the rope can only provide a unidirectional constraint force to the suspended object,which leads to the weak ability of the system to resist external disturbances and makes it difficult to control the trajectory of the suspended object.Based on the kinematics and statics of the multi-robot coordinated towing system with fixed base,the dynamic model of the system is established by using the Newton-Euler equations and the Udwadia-Kalaba equations.To plan the trajectories with high stability and strong control,trajectory planning is performed by combining the dynamics and stability of the towing system.Based on the dynamic stability of the motion trajectory of the suspended object,the stability of the suspended object is effectively improved through online real-time planning and offline manual adjustment.The effectiveness of the proposed method is verified by comparing the motion stability of the suspended object before and after planning.The results provide a foundation for the motion planning and coordinated control of the towing system. 展开更多
关键词 towing system unconstrained system trajectory planning dynamic stability
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Activity Data and Emission Factor for Forestry and Other Land Use Change Subsector to Enhance Carbon Market Policy and Action in Malawi
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作者 Edward Missanjo Henry Kadzuwa 《Journal of Environmental Protection》 2024年第4期401-414,共14页
Activity data and emission factors are critical for estimating greenhouse gas emissions and devising effective climate change mitigation strategies. This study developed the activity data and emission factor in the Fo... Activity data and emission factors are critical for estimating greenhouse gas emissions and devising effective climate change mitigation strategies. This study developed the activity data and emission factor in the Forestry and Other Land Use Change (FOLU) subsector in Malawi. The results indicate that “forestland to cropland,” and “wetland to cropland,” were the major land use changes from the year 2000 to the year 2022. The forestland steadily declined at a rate of 13,591 ha (0.5%) per annum. Similarly, grassland declined at the rate of 1651 ha (0.5%) per annum. On the other hand, cropland, wetland, and settlements steadily increased at the rate of 8228 ha (0.14%);5257 ha (0.17%);and 1941 ha (8.1%) per annum, respectively. Furthermore, the results indicate that the “grassland to forestland” changes were higher than the “forestland to grassland” changes, suggesting that forest regrowth was occurring. On the emission factor, the results interestingly indicate that there was a significant increase in carbon sequestration in the FOLU subsector from the year 2011 to 2022. Carbon sequestration increased annually by 13.66 ± 0.17 tCO<sub>2</sub> e/ha/yr (4.6%), with an uncertainty of 2.44%. Therefore, it can be concluded that there is potential for a Carbon market in Malawi. 展开更多
关键词 Activity Data Emission Factor Climate Change Forestland Carbon market
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Safe Motion Planning and Control Framework for Automated Vehicles with Zonotopic TRMPC
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作者 Hao Zheng Yinong Li +1 位作者 Ling Zheng Ehsan Hashemi 《Engineering》 SCIE EI CAS CSCD 2024年第2期146-159,共14页
Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal ... Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning layer.To address this issue,this study proposes a safe motion planning and control(SMPAC)framework for AVs.For the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller conservatism.For the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is proposed.The safety sets provide the basis for the subsequent evaluation and ranking of the generated trajectories.An efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the SMPAC.The result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties. 展开更多
关键词 Automated vehicles Automated driving Motion planning Motion control Tube MPC ZONOTOPE
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Evolutionary Decision-Making and Planning for Autonomous Driving Based on Safe and Rational Exploration and Exploitation
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作者 Kang Yuan Yanjun Huang +4 位作者 Shuo Yang Zewei Zhou Yulei Wang Dongpu Cao Hong Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期108-120,共13页
Decision-making and motion planning are extremely important in autonomous driving to ensure safe driving in a real-world environment.This study proposes an online evolutionary decision-making and motion planning frame... Decision-making and motion planning are extremely important in autonomous driving to ensure safe driving in a real-world environment.This study proposes an online evolutionary decision-making and motion planning framework for autonomous driving based on a hybrid data-and model-driven method.First,a data-driven decision-making module based on deep reinforcement learning(DRL)is developed to pursue a rational driving performance as much as possible.Then,model predictive control(MPC)is employed to execute both longitudinal and lateral motion planning tasks.Multiple constraints are defined according to the vehicle’s physical limit to meet the driving task requirements.Finally,two principles of safety and rationality for the self-evolution of autonomous driving are proposed.A motion envelope is established and embedded into a rational exploration and exploitation scheme,which filters out unreasonable experiences by masking unsafe actions so as to collect high-quality training data for the DRL agent.Experiments with a high-fidelity vehicle model and MATLAB/Simulink co-simulation environment are conducted,and the results show that the proposed online-evolution framework is able to generate safer,more rational,and more efficient driving action in a real-world environment. 展开更多
关键词 Autonomous driving DECISION-MAKING Motion planning Deep reinforcement learning Model predictive control
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General Optimal Trajectory Planning:Enabling Autonomous Vehicles with the Principle of Least Action
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作者 Heye Huang Yicong Liu +4 位作者 Jinxin Liu Qisong Yang Jianqiang Wang David Abbink Arkady Zgonnikov 《Engineering》 SCIE EI CAS CSCD 2024年第2期63-76,共14页
This study presents a general optimal trajectory planning(GOTP)framework for autonomous vehicles(AVs)that can effectively avoid obstacles and guide AVs to complete driving tasks safely and efficiently.Firstly,we emplo... This study presents a general optimal trajectory planning(GOTP)framework for autonomous vehicles(AVs)that can effectively avoid obstacles and guide AVs to complete driving tasks safely and efficiently.Firstly,we employ the fifth-order Bezier curve to generate and smooth the reference path along the road centerline.Cartesian coordinates are then transformed to achieve the curvature continuity of the generated curve.Considering the road constraints and vehicle dynamics,limited polynomial candidate trajectories are generated and smoothed in a curvilinear coordinate system.Furthermore,in selecting the optimal trajectory,we develop a unified and auto-tune objective function based on the principle of least action by employing AVs to simulate drivers’behavior and summarizing their manipulation characteristics of“seeking benefits and avoiding losses.”Finally,by integrating the idea of receding-horizon optimization,the proposed framework is achieved by considering dynamic multi-performance objectives and selecting trajectories that satisfy feasibility,optimality,and adaptability.Extensive simulations and experiments are performed,and the results demonstrate the framework’s feasibility and effectiveness,which avoids both dynamic and static obstacles and applies to various scenarios with multi-source interactive traffic participants.Moreover,we prove that the proposed method can guarantee real-time planning and safety requirements compared to drivers’manipulation. 展开更多
关键词 Autonomous vehicle Trajectory planning Multi-performance objectives Principle of least action
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Multi-UAVs Collaborative Path Planning in the Cramped Environment
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作者 Siyuan Feng Linzhi Zeng +2 位作者 Jining Liu Yi Yang Wenjie Song 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期529-538,共10页
Due to its flexibility and complementarity, the multiUAVs system is well adapted to complex and cramped workspaces, with great application potential in the search and rescue(SAR) and indoor goods delivery fields. Howe... Due to its flexibility and complementarity, the multiUAVs system is well adapted to complex and cramped workspaces, with great application potential in the search and rescue(SAR) and indoor goods delivery fields. However, safe and effective path planning of multiple unmanned aerial vehicles(UAVs)in the cramped environment is always challenging: conflicts with each other are frequent because of high-density flight paths, collision probability increases because of space constraints, and the search space increases significantly, including time scale, 3D scale and model scale. Thus, this paper proposes a hierarchical collaborative planning framework with a conflict avoidance module at the high level and a path generation module at the low level. The enhanced conflict-base search(ECBS) in our framework is improved to handle the conflicts in the global path planning and avoid the occurrence of local deadlock. And both the collision and kinematic models of UAVs are considered to improve path smoothness and flight safety. Moreover, we specifically designed and published the cramped environment test set containing various unique obstacles to evaluating our framework performance thoroughly. Experiments are carried out relying on Rviz, with multiple flight missions: random, opposite, and staggered, which showed that the proposed method can generate smooth cooperative paths without conflict for at least 60 UAVs in a few minutes.The benchmark and source code are released in https://github.com/inin-xingtian/multi-UAVs-path-planner. 展开更多
关键词 Collision avoidance conflict resolution multi-unmanned aerial vehicles(UAVs)system path planning
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Research on Anthropomorphic Obstacle Avoidance Trajectory Planning for Adaptive Driving Scenarios Based on Inverse Reinforcement Learning Theory
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作者 Jian Wu Yang Yan +1 位作者 Yulong Liu Yahui Liu 《Engineering》 SCIE EI CAS CSCD 2024年第2期133-145,共13页
The forward design of trajectory planning strategies requires preset trajectory optimization functions,resulting in poor adaptability of the strategy and an inability to accurately generate obstacle avoidance trajecto... The forward design of trajectory planning strategies requires preset trajectory optimization functions,resulting in poor adaptability of the strategy and an inability to accurately generate obstacle avoidance trajectories that conform to real driver behavior habits.In addition,owing to the strong time-varying dynamic characteristics of obstacle avoidance scenarios,it is necessary to design numerous trajectory optimization functions and adjust the corresponding parameters.Therefore,an anthropomorphic obstacle-avoidance trajectory planning strategy for adaptive driving scenarios is proposed.First,numerous expert-demonstrated trajectories are extracted from the HighD natural driving dataset.Subsequently,a trajectory expectation feature-matching algorithm is proposed that uses maximum entropy inverse reinforcement learning theory to learn the extracted expert-demonstrated trajectories and achieve automatic acquisition of the optimization function of the expert-demonstrated trajectory.Furthermore,a mapping model is constructed by combining the key driving scenario information that affects vehicle obstacle avoidance with the weight of the optimization function,and an anthropomorphic obstacle avoidance trajectory planning strategy for adaptive driving scenarios is proposed.Finally,the proposed strategy is verified based on real driving scenarios.The results show that the strategy can adjust the weight distribution of the trajectory optimization function in real time according to the“emergency degree”of obstacle avoidance and the state of the vehicle.Moreover,this strategy can generate anthropomorphic trajectories that are similar to expert-demonstrated trajectories,effectively improving the adaptability and acceptability of trajectories in driving scenarios. 展开更多
关键词 Obstacle avoidance trajectory planning Inverse reinforcement theory Anthropomorphic Adaptive driving scenarios
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