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Study on technical efficiency of traditional Chinese medicine industry of the Belt and Road Initiative based on environmental complexity
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作者 Tong Shao Yan Zhou 《Traditional Medicine Research》 2022年第2期20-26,共7页
Background:Based on the principle of“joint consultation,co-building,and sharing”,with the aim of creating an energetic new model of economic growth,the Belt and Road Initiative achieves connectivity and mutual benef... Background:Based on the principle of“joint consultation,co-building,and sharing”,with the aim of creating an energetic new model of economic growth,the Belt and Road Initiative achieves connectivity and mutual benefit.However,the degree of coordinated development of innovation subjects directly affects the improvement and optimization of the Belt and Road Initiative’s strategy implementation environment,and technology efficiency needs improvement.Methods:In this study,a data envelopment analysis model based on the environmental noise elimination algorithm(traditional Chinese medicine-Belt and Road Initiative)was used to identify the technical efficiency of the traditional Chinese medicine industry of Belt and Road Initiative by eliminating the impact of environmental factors.Results:Pure technical ineffectiveness,regional impact,and environmental factors represented by policy responses have a non-linear impact on technical efficiency.The overall technical efficiency of the traditional Chinese medicine industry in the countries along the route shows a trend of annual increases,technical efficiency and scale efficiency are relatively high,and operational efficiency is influenced by the degree of response of the countries along the route and its supporting policies.Conclusion:Pure technical inefficiency is the main factor affecting total technical loss.Geographical advantage is the key factor in operational efficiency.External environmental factors have a significant influence on the operational efficiency of the traditional Chinese medicine industry. 展开更多
关键词 traditional Chinese medicine Belt and Road Initiative environmental complexity data envelopment analysis wavelet model
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Recent Progress in Reinforcement Learning and Adaptive Dynamic Programming for Advanced Control Applications 被引量:4
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作者 Ding Wang Ning Gao +2 位作者 Derong Liu Jinna Li Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期18-36,共19页
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ... Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence. 展开更多
关键词 Adaptive dynamic programming(ADP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)
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Study on Durability of Recycled Aggregate Concrete in High-Temperature and Complex Environments
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作者 Xiaoqing Hu Yao Tong +1 位作者 Xuan Min Rongchong Xu 《Journal of World Architecture》 2024年第5期66-71,共6页
Recycled aggregate concrete refers to a new type of concrete material made by processing waste concrete materials through grading,crushing,and cleaning,and then mixing them with cement,water,and other materials in a c... Recycled aggregate concrete refers to a new type of concrete material made by processing waste concrete materials through grading,crushing,and cleaning,and then mixing them with cement,water,and other materials in a certain gradation or proportion.This type of concrete is highly suitable for modern construction waste disposal and reuse and has been widely used in various construction projects.It can also be used as an environmentally friendly permeable brick material to promote the development of modern green buildings.However,practical applications have found that compared to ordinary concrete,the durability of this type of concrete is more susceptible to high-temperature and complex environments.Based on this,this paper conducts theoretical research on its durability in high-temperature and complex environments,including the current research status,existing problems,and application prospects of recycled aggregate concrete’s durability in such environments.It is hoped that this analysis can provide some reference for studying the influence of high-temperature and complex environments on recycled aggregate concrete and its subsequent application strategies. 展开更多
关键词 Recycled aggregate concrete Construction engineering High-temperature and complex environment DURABILITY
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Precision Machining Equipment Fault Diagnosis Based on CWT and Improved ResNeXt
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作者 Lichen Shi Jiahang Guo Haitao Wang 《Instrumentation》 2024年第2期36-43,共8页
A fault diagnosis method based on continuous wavelet transform and improved multi-dimensional residual network was proposed to solve the problem that the working environment of precision machining equipment is very co... A fault diagnosis method based on continuous wavelet transform and improved multi-dimensional residual network was proposed to solve the problem that the working environment of precision machining equipment is very complicated,and the fault characteristic signal is weak and hard to extract.Firstly,the best wavelet base Cmor 3-3 is selected by comparing 6 different wavelet base types.Secondly,continuous wavelet transform(CWT)is applied to the acquired original vibration signal to generate the feature map and process the gray level.Finally,the improved ResNeXt network is used to diagnose faults in precision machining equipment.The experimental results show that the proposed CWT and the improved ResNeXt algorithm have high accuracy in identifying precision machining equipment faults in complex environments,with an average accuracy of 99.4%。 展开更多
关键词 complex working environment ResNeXt precision working equipment
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Path Planning Method Based on D^(*) lite Algorithm for Unmanned Surface Vehicles in Complex Environments 被引量:9
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作者 YAO Yan-long LIANG Xiao-feng +4 位作者 LI Ming-zhi YU Kai CHEN Zhe NI Chong-ben TENG Yue 《China Ocean Engineering》 SCIE EI CSCD 2021年第3期372-383,共12页
In recent decades,path planning for unmanned surface vehicles(USVs)in complex environments,such as harbours and coastlines,has become an important concern.The existing algorithms for real-time path planning for USVs a... In recent decades,path planning for unmanned surface vehicles(USVs)in complex environments,such as harbours and coastlines,has become an important concern.The existing algorithms for real-time path planning for USVs are either too slow at replanning or unreliable in changing environments with multiple dynamic obstacles.In this study,we developed a novel path planning method based on the D^(*) lite algorithm for real-time path planning of USVs in complex environments.The proposed method has the following advantages:(1)the computational time for replanning is reduced significantly owing to the use of an incremental algorithm and a new method for modelling dynamic obstacles;(2)a constrained artificial potential field method is employed to enhance the safety of the planned paths;and(3)the method is practical in terms of vehicle performance.The performance of the proposed method was evaluated through simulations and compared with those of existing algorithms.The simulation results confirmed the efficiency of the method for real-time path planning of USVs in complex environments. 展开更多
关键词 path planning unmanned surface vehicle D^(*)lite algorithm complex environment
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Switching variability index based multiple strategy CFAR detector 被引量:4
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作者 Yang Li Zhenyuan Ji +1 位作者 Bingfei Li Gil Alterovitz 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期580-587,共8页
A switching variability index (SVl) constant false alarm rate (CFAR) detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homo... A switching variability index (SVl) constant false alarm rate (CFAR) detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homogeneity in CFAR reference windows is indicated by a VI-CFAR detector, a switching- CFAR detector is introduced to optimize the performance of the VI-CFAR detector in homogeneous, multiple targets and clutter edge backgrounds. The structure and parameters selection method of the SVI-CFAR detector is presented. Comparisons with classic CFAR detectors and recently proposed detectors are also given. Theoretical analysis and simulation results show that SVICFAR detector maintains the good performance of the VI-CFAR detector in homogeneous and clutter edge backgrounds, while greatly improving the capacity of anti-multi targets. 展开更多
关键词 switching variability index constant false alarm rate(SVI-CFAR) adaptive detection complex environment multiple-strategy detection radar target detection.
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Dynamic analysis of wind turbine tower structures in complex ocean environment 被引量:2
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作者 Guanzhong LIU Xingming GUO Li ZHU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第7期999-1010,共12页
Studying and analyzing the dynamic behavior of offshore wind turbines are of great importance to ensure the safety and improve the efficiency of such expensive equipments.In this work,a tapered beam model is proposed ... Studying and analyzing the dynamic behavior of offshore wind turbines are of great importance to ensure the safety and improve the efficiency of such expensive equipments.In this work,a tapered beam model is proposed to investigate the dynamic response of an offshore wind turbine tower on the monopile foundation assembled with rotating blades in the complex ocean environment.Several environment factors like wind,wave,current,and soil resistance are taken into account.The proposed model is ana-lytically solved with the Galerkin method.Based on the numerical results,the effects of various structure parameters including the taper angle,the height and thickness of the tower,the depth,and the diameter and the cement filler of the monopile on the funda-mental natural frequency of the wind turbine tower system are investigated in detail.It is found that the fundamental natural frequency decreases with the increase in the taper angle and the height and thickness of the tower,and increases with the increase in the diameter of the monopile.Moreover,filling cement into the monopile can effectively im-prove the fundamental natural frequency of the wind turbine tower system,but there is a critical value of the amount of cement maximizing the property of the monopile.This research may be helpful in the design and safety evaluation of offshore wind turbines. 展开更多
关键词 wind turbine tower structure dynamic analysis tapered beam fundamen-tal natural frequency complex ocean environment
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Comprehensive analysis of safe mining to heavy and steep coal seam under complex geophysics environment 被引量:3
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作者 王宁波 李立波 +1 位作者 来兴平 柴鑫 《Journal of Coal Science & Engineering(China)》 2008年第3期378-381,共4页
In virtue of effect of N-S intensive ground stress and mining disturbance to +579E2EB_(1+2) mining site at Weihuliang Mine,the dip angle and section height is 65° and 52 m,respectively,the collapses happed freque... In virtue of effect of N-S intensive ground stress and mining disturbance to +579E2EB_(1+2) mining site at Weihuliang Mine,the dip angle and section height is 65° and 52 m,respectively,the collapses happed frequently during mining.Firstly,mining condi- tions,spatial structure and parameters were investigated.Then physical simulation and dynamic numerical tracing and elaborate simulation relating roof and top-coal were ap- plied based on 2D-Block Program and quantitative regularity of stress at variable depths had been estimated.Furthermore,it was manifested that effective measures,i.e.,fast mining,control symmetrical top-coal-caving at dip and strike directions,optimizing ventila- tion system,active-stereo preventing gas were performed successfully in mining practice. Ultimately,the derived dynamic hazard were prevented so as to safety mining. 展开更多
关键词 complex geophysics environment heavy-steep coal seam high-section-top- coal-caving(HSTCC) excavation disturbance zone(EDZ) dynamic destabilization
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An improved Gmapping algorithm based map construction method for indoor mobile robot 被引量:1
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作者 Tao yong Jiang Shan +2 位作者 Ren Fan Wang Tianmiao Gao He 《High Technology Letters》 EI CAS 2021年第3期227-237,共11页
With the rapid development in the service,medical,logistics and other industries,and the increasing demand for unmanned mobile devices,mobile robots with the ability of independent mapping,localization and navigation ... With the rapid development in the service,medical,logistics and other industries,and the increasing demand for unmanned mobile devices,mobile robots with the ability of independent mapping,localization and navigation capabilities have become one of the research hotspots.An accurate map construction is a prerequisite for a mobile robot to achieve autonomous localization and navigation.However,the problems of blurring and missing the borders of obstacles and map boundaries are often faced in the Gmapping algorithm when constructing maps in complex indoor environments.In this pursuit,the present work proposes the development of an improved Gmapping algorithm based on the sparse pose adjustment(SPA)optimizations.The improved Gmapping algorithm is then applied to construct the map of a mobile robot based on single-line Lidar.Experiments show that the improved algorithm could build a more accurate and complete map,reduce the number of particles required for Gmapping,and lower the hardware requirements of the platform,thereby saving and minimizing the computing resources. 展开更多
关键词 complex indoor environment single-line Lidar map construction improved Gmapping algorithm sparse pose adjustment(SPA)optimization
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Middleware Challenges in Robotic Fleets for Precision Agriculture
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作者 Domagoj Drenjanac Slobodanka Dana Kathrin Tomic 《Journal of Mechanics Engineering and Automation》 2013年第11期702-714,共13页
The past decade has witnessed a huge increase in the number of proposed middleware solutions for robotic fleets operating in unstructured environments. As a result, it has become difficult to decide which middleware i... The past decade has witnessed a huge increase in the number of proposed middleware solutions for robotic fleets operating in unstructured environments. As a result, it has become difficult to decide which middleware is the most appropriate for a specific application or application domain. In this paper we first extract a set of common and specific challenges that middlewares address, and group them according to the source domain they have originated within. These challenges are derived from a specific precision agriculture use-case based on the robotic fleet for weed control elaborated within the European project RHEA-robot fleets for highly effective agriculture and forestry management. Furthermore, the paper provides an analysis of a number of different middlewares and suggests a set of criteria for systemizing representative solutions. The aim of this analysis is to assist the process of finding an adequate middleware for a specific application domain. 展开更多
关键词 Robotic middleware robotic fleets complex environment multi-robot system.
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The mechanism of environmental D-xylose perception by the bacterial membrane two-component complex XylFII-LytS
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《Science Foundation in China》 CAS 2017年第4期23-,共1页
D-xylose,the main building block of plant biomass,is a pentose sugar that can be used by bacteria as a carbon source for bio-based fuel and chemical production through fermentation.In bacteria,the first step for D-xyl... D-xylose,the main building block of plant biomass,is a pentose sugar that can be used by bacteria as a carbon source for bio-based fuel and chemical production through fermentation.In bacteria,the first step for D-xylose metabolism is signal perception at the membrane.Scientists previously identified a threecomponent system in Firmicutes bacteria comprising a membrane-associated sensor protein(XylFII)。 展开更多
关键词 The mechanism of environmental D-xylose perception by the bacterial membrane two-component complex XylFII-LytS
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Path Planning in Complex 3D Environments Using a Probabilistic Roadmap Method 被引量:14
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作者 Fei Yan Yi-Sha Liu Ji-Zhong Xiao 《International Journal of Automation and computing》 EI CSCD 2013年第6期525-533,共9页
This paper presents a 3D path planning algorithm for an unmanned aerial vehicle (UAV) in complex environments. In this algorithm, the environments are divided into voxels by octree algorithm. In order to satisfy the... This paper presents a 3D path planning algorithm for an unmanned aerial vehicle (UAV) in complex environments. In this algorithm, the environments are divided into voxels by octree algorithm. In order to satisfy the safety requirement of the UAV, free space is represented by free voxels, which have enough space margin for the UAV to pass through. A bounding box array is created in the whole 3D space to evaluate the free voxel connectivity. The probabilistic roadmap method (PRM) is improved by random sampling in the bounding box array to ensure a more efficient distribution of roadmap nodes in 3D space. According to the connectivity evaluation, the roadmap is used to plan a feasible path by using A* algorithm. Experimental results indicate that the proposed algorithm is valid in complex 3D environments. 展开更多
关键词 3D path planning complex environment unmanned aerial vehicle (UAV) probabilistic roadmap methed (PRM) octree.
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Target localization method of non-cooperative spacecraft on on-orbit service 被引量:3
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作者 Yingxiao LI Ju HUO +1 位作者 Ping MA Ruiye JIANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第11期336-348,共13页
With the explosion of the number of meteoroid/orbital debris in terrestrial space in recent years, the detection environment of spacecraft becomes more complex. This phenomenon causes most current detection methods ba... With the explosion of the number of meteoroid/orbital debris in terrestrial space in recent years, the detection environment of spacecraft becomes more complex. This phenomenon causes most current detection methods based on machine learning intractable to break through the two difficulties of solving scale transformation problem of the targets in image and accelerating detection rate of high-resolution images. To overcome the two challenges, we propose a novel noncooperative target detection method using the framework of deep convolutional neural network.Firstly, a specific spacecraft simulation dataset using over one thousand images to train and test our detection model is built. The deep separable convolution structure is applied and combined with the residual network module to improve the network’s backbone. To count the different shapes of the spacecrafts in the dataset, a particular prior-box generation method based on K-means cluster algorithm is designed for each detection head with different scales. Finally, a comprehensive loss function is presented considering category confidence, box parameters, as well as box confidence. The experimental results verify that the proposed method has strong robustness against varying degrees of luminance change, and can suppress the interference caused by Gaussian noise and background complexity. The mean accuracy precision of our proposed method reaches 93.28%, and the global loss value is 13.252. The comparative experiment results show that under the same epoch and batchsize, the speed of our method is compressed by about 20% in comparison of YOLOv3, the detection accuracy is increased by about 12%, and the size of the model is reduced by nearly 50%. 展开更多
关键词 Spacecraft service High resolution image Object detection Complex environment Lightweight model
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Scientific problems and research proposals for Sichuan–Tibet railway tunnel construction 被引量:9
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作者 Dingli Zhang Zhenyu Sun Qian Fang 《Underground Space》 SCIE EI 2022年第3期419-439,共21页
The Sichuan–Tibet railway construction has received significant attention from both China and abroad.The new section from Ya’an to Nyingchi is about 1018.6 km long,including 69 tunnels with a total length of 841.7 k... The Sichuan–Tibet railway construction has received significant attention from both China and abroad.The new section from Ya’an to Nyingchi is about 1018.6 km long,including 69 tunnels with a total length of 841.7 km.The longest tunnel(Yigong tunnel)is 42.4 km long.The successful construction of the Sichuan–Tibet railway depends largely on tunnel construction.Due to the complex conditions,tunnel construction for the Sichuan–Tibet railway poses great challenges to the research community.This paper aims to illustrate the necessity of interdisciplinary and joint research to solve problems associated with tunnel construction that will be encountered in the immediate future and facilitate the communication and exchange of ideas between disciplines.To this end,based on a systematic analysis of the available data related to Sichuan–Tibet railway tunnels,six major aspects of the geology,environment,and engineering conditions are identified.Next,based on the engineering responses from the Sichuan–Tibet railway tunnels,potential technical problems and risk characteristics are predicted and evaluated.Further,six key scientific issues are identified and discussed based on a coupled multi-layer analysis of essential tunnel engineering issues.Finally,research directions,technical ideas,and research methods that should be carried out for this project are proposed. 展开更多
关键词 Sichuan–Tibet railway tunnels Key scientific problems Complex stress environment Deformation mechanism of surrounding rock Dynamic response
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COMPARISONS OF RAY-TRACING AND PARABOLIC EQUATION METHODS FOR THE LARGE-SCALE COMPLEX ELECTROMAGNETIC ENVIRONMENT SIMULATIONS 被引量:1
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作者 YUEWEI SHEN LIN ZHANG +3 位作者 DENGKUN LIU YINGNIAN WU LAN MU ALPH CHUNTSINGER 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2012年第2期42-68,共27页
It is important for the wireless communication field to conduct research on large-scale complex electromagnetic environment(CEME)simulation.There exist many models for computing CEME simulation,including empirical mod... It is important for the wireless communication field to conduct research on large-scale complex electromagnetic environment(CEME)simulation.There exist many models for computing CEME simulation,including empirical models,half-empirical or halfdeterministic models and deterministic models.Most of these models cannot obtain satisfactory results due to the limitation of the capacity of computers.The ray tracing(RT)and parabolic equation(PE)methods are very suitable for large-scale CEME simulation.Based on the introduction of RT and PE,qualitative comparisons of the two methods are analyzed in view of algorithm theory,the category of the model,solution to the model and the application field,and then four specific indices are focused on to analyze the computational complexity,accuracy,speed and parallelism in details.The numerical experiments are presented by the three-dimensional(3D)RT method employing the software of Wireless InSite(WI)and a quasi-3DPE method using the sliced method.Although both RT and PE methods can achieve high speedup using coarse-grained parallel computing,the experimental results indicate that the PE method can obtain a higher speed than the RT method,and the two methods can acquire an approximate precision.A hybrid procedure using both RT and PE methods can obtain a better result for solving CEME problems. 展开更多
关键词 Complex electromagnetic environment(CEME) ray tracing(RT) threedimensional parabolic equation(3DPE) complexity parallelism.
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