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The Gut Brain Connection
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作者 Saeed Alzubide Muslih Alhalafi 《Journal of Behavioral and Brain Science》 2024年第3期103-117,共15页
The gut-brain connection is a bidirectional communication system that links the gut microbiome to the central nervous system (CNS). The gut-brain axis communicates through a variety of mechanisms, including the releas... The gut-brain connection is a bidirectional communication system that links the gut microbiome to the central nervous system (CNS). The gut-brain axis communicates through a variety of mechanisms, including the release of hormones, neurotransmitters, and cytokines. These signaling molecules can travel from the gut to the brain and vice versa, influencing various physiological and cognitive functions. Emerging therapeutic strategies targeting the gut-brain connection include probiotics, prebiotics, and faecal microbiota transplantation (FMT). Probiotics are live microorganisms that are similar to the beneficial bacteria that are naturally found in the gut. Prebiotics are non-digestible fibers that feed the beneficial bacteria in the gut. FMT is a procedure in which faecal matter from a healthy donor is transplanted into the gut of a person with a diseased microbiome. Probiotics, prebiotics, and FMT have been shown to be effective in treating a variety of gastrointestinal disorders, and there is growing evidence that they may also be effective in treating neurological and psychiatric disorders. This review explores the emerging field of the gut-brain connection, focusing on the communication pathways between the gut microbiome and the central nervous system. We summarize the potential roles of gut dysbiosis in various neurological and psychiatric disorders. Additionally, we discuss potential therapeutic strategies, research limitations, and future directions in this exciting area of research. More research is needed to fully understand the mechanisms underlying the gut-brain connection and to develop safe and effective therapies that target this pathway. However, the findings to date are promising, and there is the potential to revolutionize the way we diagnose and treat a variety of neurological and psychiatric disorders. 展开更多
关键词 gut-brain connection gut-brain Axis Enteric Nervous System Microbiota NEUROTRANSMITTERS Neuroinflammation and Mental Health
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Ultra Reliable Load-Aware Connection Management(LACM)Algorithm in WIA-FA Systems
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作者 Liu Gang Jiang Chunhao +3 位作者 Ren Xiaochun Fan Pingzhi Liang Chengchao Ma Zheng 《China Communications》 SCIE CSCD 2024年第8期142-161,共20页
The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication technology.As an international standard based on 802.11,Wir... The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication technology.As an international standard based on 802.11,Wireless networks for Industrial Automation-Factory Automation(WIA-FA)greatly improves the reliability in factory automation scenarios by Time Division Multiple Access(TDMA).However,in ultra-dense WIA-FA networks with mobile users,the basic connection management mechanism is inefficient.Most of the handover and resource management algorithms are all based on frequency division multiplexing,not suitable for the TDMA in the WIA-FA network.Therefore,we propose Load-aware Connection Management(LACM)algorithm to adjust the linkage and balance the load of access devices to avoid blocking and improve the reliability of the system.And then we simulate the algorithm to find the optimal settings of the parameters.After comparing with other existing algorithms,the result of the simulation proves that LACM is more efficient in reliability and maintains high reliability of more than 99.8%even in the ultra-dense moving scenario with 1500 field devices.Besides,this algorithm ensures that only a few signaling exchanges are required to ensure load bal-ancing,which is no more than 5 times,and less than half of the best state-of-the-art algorithm. 展开更多
关键词 connection management load-aware multi-connectivity reliability RETRANSMISSION WIAFA
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Seismic fragility analysis of three-tower cable-stayed bridges with different connection configurations
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作者 Chen Chen Liu Jinlong +1 位作者 Lin Junqi Li Suchao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期1009-1027,共19页
Seismic fragility analysis of three-tower cable-stayed bridges with three different structural systems,including rigid system(RS),floating system(FS),and passive energy dissipation system(PEDS),is conducted to study t... Seismic fragility analysis of three-tower cable-stayed bridges with three different structural systems,including rigid system(RS),floating system(FS),and passive energy dissipation system(PEDS),is conducted to study the effects of connection configurations on seismic responses and fragilities.Finite element models of bridges are established using OpenSees.A new ground motion screening method based on the statistical characteristic of the predominant period is proposed to avoid irregular behavior in the selection process of ground motions,and incremental dynamic analysis(IDA)is performed to develop components and systems fragility curves.The effects of damper failure on calculated results for PEDS are examined in terms of seismic response and fragility analysis.The results show that the bridge tower is the most affected component by different structural systems.For RS,the fragility of the middle tower is significantly higher than other components,and the bridge failure starts from the middle tower,exhibiting a characteristic of local failure.For FS and PEDS,the fragility of the edge tower is higher than the middle tower.The system fragility of RS is higher than FS and PEDS.Taking the failure of dampers into account is necessary to obtain reliable seismic capacity of cable-stayed bridges. 展开更多
关键词 seismic fragility cable-stayed bridge connection configuration viscous damper comparison analysis
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Electromechanical Transient Modeling Analysis of Large-Scale New Energy Grid Connection
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作者 Shichao Cao Yonggang Dong Xiaoying Liu 《Energy Engineering》 EI 2024年第4期1109-1125,共17页
The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance a... The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance as the generator.It is the key technology to realize new energy grid connections’stable and reliable operation.This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is proposed.The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter constraint.The rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by interference.The branch transient of the critical cut set in the system can be confined to a limited area.Thus,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous state.The simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this paper.This paper provides a theoretical basis for improving the transient stability of new energy-connected power grids. 展开更多
关键词 New energy grid connection transient electromechanical modeling synchronous virtual machine PSASP software energy storage
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Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data
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作者 JIANG Hongqiang WEI Ye +1 位作者 MEI Lin WANG Zhaobo 《Chinese Geographical Science》 SCIE CSCD 2024年第3期533-547,共15页
Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and... Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination planning.This paper uses geotagging data to compare the links between attractions in Beijing,China during four different periods:the pre-Olympic period(2004–2007),the Olympic Games and subsequent‘heat period’(2008–2013),the post-Olympic period(2014–2019),and the COVID-19(Corona Virus Disease 2019)pandemic period(2020–2021).The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the destination.The results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism networks.The macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high value.The mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of clusters.The pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four different periods has a very similar importance profile structure suggesting that the attraction network has the same construction rules and evolution mechanism,which aids in understanding the attraction network pattern at both macro and micro scales.Important approaches and practical implications for planners and managers are presented. 展开更多
关键词 attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning Beijing China
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A Clean Connection
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作者 GE LIJUN 《ChinAfrica》 2024年第12期48-49,共2页
As companies look to reduce their carbon footprint,the green electricity market is growing by leaps and bounds in China By purchasing Green Electricity Certificates(GECs),the organisers of the seventh China Internatio... As companies look to reduce their carbon footprint,the green electricity market is growing by leaps and bounds in China By purchasing Green Electricity Certificates(GECs),the organisers of the seventh China International Import Expo(CIIE)have succeeded in making the once energy-intensive event more environmentally friendly. 展开更多
关键词 COMPANIES CLEAN connection
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Smart Connection
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作者 ZHAO YANG 《ChinAfrica》 2024年第10期48-49,共2页
Digital services stand out at this year’s China International Fair for Trade in Services.Visitors gathered around a large screen displaying scenes from the video game Black Myth:Wukong,China’s first AAA title,where ... Digital services stand out at this year’s China International Fair for Trade in Services.Visitors gathered around a large screen displaying scenes from the video game Black Myth:Wukong,China’s first AAA title,where they learnt that the monkey king can move with lifelike fluidity,performing seamless actions,thanks to Virtual Motion’s state-of-the-art motion capture technology. 展开更多
关键词 connection SERVICES SERVICES
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Cost Optimization of Steel Beam-to-Column Connections using AVOA
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作者 Ziyu Wang Zhaoyang Ren 《Journal of Architectural Research and Development》 2024年第2期18-23,共6页
The joint-bolt-African Vulture optimization algorithm(AVOA)model is proposed for the design of building connections to improve the stability of steel beam-to-column connections.For this algorithm,the type of steel is ... The joint-bolt-African Vulture optimization algorithm(AVOA)model is proposed for the design of building connections to improve the stability of steel beam-to-column connections.For this algorithm,the type of steel is first determined,and the number of bolts needed by the corresponding steel type is referenced in Eurocode 3.Then,the bearing capacity of the joint can be calculated.The joint-bolt-AVOA model is established by substituting the bolt number required by the steel into the algorithm to obtain the optimal bolt number required while ensuring joint stability.The results show that the number of bolts required by the joint-bolt-AVOA model based on the stability of steel is lower than that calculated by Eurocode 3.Therefore,AVOA can effectively optimize the number of bolts needed in building connections and save resources. 展开更多
关键词 Steel connections African vulture optimization algorithm Optimization of bolts
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改进RRT-Connect与DWA算法的巡检机器人路径规划研究 被引量:1
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作者 罗征志 韩怡可 +1 位作者 张鑫 邹宇博 《计算机工程与应用》 CSCD 北大核心 2024年第15期344-354,共11页
针对传统RRT-Connect算法在密集复杂环境中路径规划效率低、动态避障效果差等问题,提出一种改进RRT-Connect与DWA融合算法。该算法通过改进采样策略、动态步长优化和碰撞检测引导随机树生长;在随机树中采用贪心策略和角度约束优化路径... 针对传统RRT-Connect算法在密集复杂环境中路径规划效率低、动态避障效果差等问题,提出一种改进RRT-Connect与DWA融合算法。该算法通过改进采样策略、动态步长优化和碰撞检测引导随机树生长;在随机树中采用贪心策略和角度约束优化路径。基于巡检机器人建立运动学模型,通过速度采样空间生成轨迹簇;建立模糊逻辑系统自适应调整DWA算法评价函数的权重系数,将全局最优路径点融入DWA算法中实现全局最优路径和实时避障。仿真结果表明,在油气站场密集复杂环境中,改进RRT-Connect算法较传统算法路径缩短约27.09%,平滑度提高约84.6%,碰撞距离提高约18.75%;改进融合算法路径减少约2.97%,平滑度提高约78.8%,碰撞距离提高约30.6%,验证了提出算法的有效性。 展开更多
关键词 路径规划 改进RRT-connect算法 DWA算法 融合算法
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基于逆向重布线改进RRT-Connect算法的机械臂路径规划
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作者 王博 顾寄南 李兴家 《江苏科技大学学报(自然科学版)》 CAS 2024年第2期47-52,共6页
为解决RRT-Connect算法在复杂非结构环境下规划出的路径成本较长、有效节点数过多、曲折不平滑等问题,提出了一种基于逆向重布线的改进RRT-Connect算法(Improved-RRT-Connect).首先,在算法的起始位置加入碰撞检测函数,当起点和终点之间... 为解决RRT-Connect算法在复杂非结构环境下规划出的路径成本较长、有效节点数过多、曲折不平滑等问题,提出了一种基于逆向重布线的改进RRT-Connect算法(Improved-RRT-Connect).首先,在算法的起始位置加入碰撞检测函数,当起点和终点之间不存在障碍物时,能够快速生成一条路径;其次,通过对生成的路径采取逆向重布线的措施,对生成的路径中的节点进行重新筛选布线,达到缩短生成路径长度,减少有效节点数量的目的;最后,通过结合B样条曲线对生成的路径进行拟合处理,得到一条平滑连续的路径.通过Improved-RRT-Connect算法与RRT、RRT^(*)-Smart、RRT-Connect等算法的对比实验表明,在规划时间上,Improved-RRT-Connect算法比RRT、RRT^(*)-Smart算法减少了52.14%、98.53%,在路径成本上比RRT、RRT-Connect算法减少了19.39%、17.15%,阐明了提出的Improved-RRT-Connect算法的优越性. 展开更多
关键词 RRT-connect算法 机械臂 碰撞检测 逆向重布线 B样条曲线
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Age-related hearing loss accelerates the decline in fast speech comprehension and the decompensation of cortical network connections 被引量:3
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作者 He-Mei Huang Gui-Sheng Chen +10 位作者 Zhong-Yi Liu Qing-Lin Meng Jia-Hong Li Han-Wen Dong Yu-Chen Chen Fei Zhao Xiao-Wu Tang Jin-Liang Gao Xi-Ming Chen Yue-Xin Cai Yi-Qing Zheng 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第9期1968-1975,共8页
Patients with age-related hearing loss face hearing difficulties in daily life.The causes of age-related hearing loss are complex and include changes in peripheral hearing,central processing,and cognitive-related abil... Patients with age-related hearing loss face hearing difficulties in daily life.The causes of age-related hearing loss are complex and include changes in peripheral hearing,central processing,and cognitive-related abilities.Furthermore,the factors by which aging relates to hearing loss via changes in audito ry processing ability are still unclear.In this cross-sectional study,we evaluated 27 older adults(over 60 years old) with age-related hearing loss,21 older adults(over 60years old) with normal hearing,and 30 younger subjects(18-30 years old) with normal hearing.We used the outcome of the uppe r-threshold test,including the time-compressed thres h old and the speech recognition threshold in noisy conditions,as a behavioral indicator of auditory processing ability.We also used electroencephalogra p hy to identify presbycusis-related abnormalities in the brain while the participants were in a spontaneous resting state.The timecompressed threshold and speech recognition threshold data indicated significant diffe rences among the groups.In patients with age-related hearing loss,information masking(babble noise) had a greater effect than energy masking(speech-shaped noise) on processing difficulties.In terms of resting-state electroencephalography signals,we observed enhanced fro ntal lobe(Brodmann’s area,BA11) activation in the older adults with normal hearing compared with the younger participants with normal hearing,and greater activation in the parietal(BA7) and occipital(BA19) lobes in the individuals with age-related hearing loss compared with the younger adults.Our functional connection analysis suggested that compared with younger people,the older adults with normal hearing exhibited enhanced connections among networks,including the default mode network,sensorimotor network,cingulo-opercular network,occipital network,and frontoparietal network.These results suggest that both normal aging and the development of age-related hearing loss have a negative effect on advanced audito ry processing capabilities and that hearing loss accele rates the decline in speech comprehension,especially in speech competition situations.Older adults with normal hearing may have increased compensatory attentional resource recruitment represented by the to p-down active listening mechanism,while those with age-related hearing loss exhibit decompensation of network connections involving multisensory integration. 展开更多
关键词 age-related hearing loss aging ELECTROENCEPHALOGRAPHY fast-speech comprehension functional brain network functional connectivity restingstate SLORETA source analysis speech reception threshold
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Topological Aspects of Dendrimers via Connection-Based Descriptors 被引量:1
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作者 Muhammad Javaid Ahmed Alamer Aqsa Sattar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1649-1667,共19页
Topological indices(TIs)have been practiced for distinct wide-ranging physicochemical applications,especially used to characterize and model the chemical structures of various molecular compounds such as dendrimers,na... Topological indices(TIs)have been practiced for distinct wide-ranging physicochemical applications,especially used to characterize and model the chemical structures of various molecular compounds such as dendrimers,nanotubes and neural networks with respect to their certain properties such as solubility,chemical stability and low cytotoxicity.Dendrimers are prolonged artificially synthesized or amalgamated natural macromolecules with a sequential layer of branches enclosing a central core.A present-day trend in mathematical and computational chemistry is the characterization of molecular structure by applying topological approaches,including numerical graph invariants.Among topological descriptors,Zagreb connection indices(ZCIs)have much importance.This manuscript involves the establishment of general results to calculate ZCIs,namely first ZCI(FZCI),second ZCI(SZCI),third ZCI(TZCI),modified FZCI,modified SZCI and modified TZCI of two special types of dendrimers nanostars,namely,poly propylene imine octamin(PPIO)dendrimer and poly(propyl)ether imine(PPEtIm)dendrimer.Furthermore,we provide the numerical and graphical comparative analysis of our calculated results for both types of dendrimers with each other. 展开更多
关键词 Zagreb indices zagreb connection indices topological index dendrimer nanostars
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Unraveling the gut-brain axis:the impact of steroid hormones and nutrition on Parkinson's disease 被引量:3
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作者 Paula Maria Neufeld Ralf A.Nettersheim +3 位作者 Veronika Matschke Matthias Vorgerd Sarah Stahlke Carsten Theiss 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第10期2219-2228,共10页
This comprehensive review explores the intricate relationship between nutrition,the gut microbiome,steroid hormones,and Parkinson's disease within the context of the gut-brain axis.The gut-brain axis plays a pivot... This comprehensive review explores the intricate relationship between nutrition,the gut microbiome,steroid hormones,and Parkinson's disease within the context of the gut-brain axis.The gut-brain axis plays a pivotal role in neurodegenerative diseases like Parkinson's disease,encompassing diverse components such as the gut microbiota,immune system,metabolism,and neural pathways.The gut microbiome,profoundly influenced by dietary factors,emerges as a key player.Nutrition during the first 1000 days of life shapes the gut microbiota composition,influencing immune responses and impacting both child development and adult health.High-fat,high-sugar diets can disrupt this delicate balance,contributing to inflammation and immune dysfunction.Exploring nutritional strategies,the Mediterranean diet's anti-inflammatory and antioxidant properties show promise in reducing Parkinson's disease risk.Microbiome-targeted dietary approaches and the ketogenic diet hold the potential in improving brain disorders.Beyond nutrition,emerging research uncovers potential interactions between steroid hormones,nutrition,and Parkinson's disease.Progesterone,with its anti-inflammatory properties and presence in the nervous system,offers a novel option for Parkinson's disease therapy.Its ability to enhance neuroprotection within the enteric nervous system presents exciting prospects.The review addresses the hypothesis thatα-synuclein aggregates originate from the gut and may enter the brain via the vagus nerve.Gastrointestinal symptoms preceding motor symptoms support this hypothesis.Dysfunctional gut-brain signaling during gut dysbiosis contributes to inflammation and neurotransmitter imbalances,emphasizing the potential of microbiota-based interventions.In summary,this review uncovers the complex web of interactions between nutrition,the gut microbiome,steroid hormones,and Parkinson's disease within the gut-brain axis framework.Understanding these connections not only offers novel therapeutic insights but also illuminates the origins of neurodegenerative diseases such as Parkinson's disease. 展开更多
关键词 diet gut-brain axis microbiome neurodegenerative diseases NUTRITION Parkinson's disease PROGESTERONE steroid hormones
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Immune regulation of the gut-brain axis and lung-brain axis involved in ischemic stroke 被引量:4
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作者 Xiaodi Xie Lei Wang +2 位作者 Shanshan Dong ShanChun Ge Ting Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期519-528,共10页
Local ischemia often causes a series of inflammatory reactions when both brain immune cells and the peripheral immune response are activated.In the human body,the gut and lung are regarded as the key reactional target... Local ischemia often causes a series of inflammatory reactions when both brain immune cells and the peripheral immune response are activated.In the human body,the gut and lung are regarded as the key reactional targets that are initiated by brain ischemic attacks.Mucosal microorganisms play an important role in immune regulation and metabolism and affect blood-brain barrier permeability.In addition to the relationship between peripheral organs and central areas and the intestine and lung also interact among each other.Here,we review the molecular and cellular immune mechanisms involved in the pathways of inflammation across the gut-brain axis and lung-brain axis.We found that abnormal intestinal flora,the intestinal microenvironment,lung infection,chronic diseases,and mechanical ventilation can worsen the outcome of ischemic stroke.This review also introduces the influence of the brain on the gut and lungs after stroke,highlighting the bidirectional feedback effect among the gut,lungs,and brain. 展开更多
关键词 enteric glia cells gut microbiota gut-brain axis immune response inflammation ischemic stroke lung-brain axis microglia
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基于改进RRT-Connect算法的全局路径规划
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作者 朱建军 王明森 《组合机床与自动化加工技术》 北大核心 2024年第4期52-55,61,共5页
针对RRT-Connect算法在复杂环境内的路径规划中存在探索性弱、收敛速度慢、冗余节点多、搜索路径较长等问题,提出一种改进的RRT-Connect算法。通过引入高质量随机点和动态步长的方法,提高了生成随机树的质量并减少了冗余节点数量;采用... 针对RRT-Connect算法在复杂环境内的路径规划中存在探索性弱、收敛速度慢、冗余节点多、搜索路径较长等问题,提出一种改进的RRT-Connect算法。通过引入高质量随机点和动态步长的方法,提高了生成随机树的质量并减少了冗余节点数量;采用正向寻优和逆向贪婪的方式,改善了搜索路径较长的问题。实验结果表明,改进RRT-Connect算法平均路径规划时间缩短26.41%,平均路径规划长度缩短19.05%,平均路径规划节点个数减少41.91%,证明了改进RRT-Connect算法相比于原算法规划效率更高,规划时间更少,规划路径质量更优。 展开更多
关键词 路径规划 RRT-connect算法 动态步长 轨迹优化 贪婪算法 3次B样条曲线
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Analytical Investigation into the Rotational Performance of Glulam Bolted Beam-Column Connections under Coupled Bending Moment and Shear Force
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作者 Xiaofeng Zhang Lisheng Luo +2 位作者 Youfu Sun Xinyue Cui Yongqiang Zhang 《Journal of Renewable Materials》 SCIE EI 2023年第4期2033-2054,共22页
Considering the glulam beam-column connection form and the number of bolts,monotonic loading test and finite element analysis was carried out on 9 connection specimens in 3 groups to study the rotational performance a... Considering the glulam beam-column connection form and the number of bolts,monotonic loading test and finite element analysis was carried out on 9 connection specimens in 3 groups to study the rotational performance and failure mode of the connection.The test results revealed that compared with U-shaped connectors,T-shaped connectors can effectively improve the ductility of connections,and the increase in the number of bolts can reduce the initial stiffness and ductility of connections.By theoretical analysis,formulas for calculating the initial stiffness and ultimate moment of connections were deduced.Subsequently,the moment-rotation theoretical model of connections was established based on the formulas,which were validated according to the test data and simulation results.The proposed model can not only improve the current theoretical system of heavy-duty glulam beam-column structure but also provide a theoretical basis for calculating the mechanical properties of the glulam beam-column connection. 展开更多
关键词 Beam-column connection mechanical properties STIFFNESS ultimate moment
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Ensuring Secure Platooning of Constrained Intelligent and Connected Vehicles Against Byzantine Attacks:A Distributed MPC Framework 被引量:1
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作者 Henglai Wei Hui Zhang +1 位作者 Kamal AI-Haddad Yang Shi 《Engineering》 SCIE EI CAS CSCD 2024年第2期35-46,共12页
This study investigates resilient platoon control for constrained intelligent and connected vehicles(ICVs)against F-local Byzantine attacks.We introduce a resilient distributed model-predictive platooning control fram... This study investigates resilient platoon control for constrained intelligent and connected vehicles(ICVs)against F-local Byzantine attacks.We introduce a resilient distributed model-predictive platooning control framework for such ICVs.This framework seamlessly integrates the predesigned optimal control with distributed model predictive control(DMPC)optimization and introduces a unique distributed attack detector to ensure the reliability of the transmitted information among vehicles.Notably,our strategy uses previously broadcasted information and a specialized convex set,termed the“resilience set”,to identify unreliable data.This approach significantly eases graph robustness prerequisites,requiring only an(F+1)-robust graph,in contrast to the established mean sequence reduced algorithms,which require a minimum(2F+1)-robust graph.Additionally,we introduce a verification algorithm to restore trust in vehicles under minor attacks,further reducing communication network robustness.Our analysis demonstrates the recursive feasibility of the DMPC optimization.Furthermore,the proposed method achieves exceptional control performance by minimizing the discrepancies between the DMPC control inputs and predesigned platoon control inputs,while ensuring constraint compliance and cybersecurity.Simulation results verify the effectiveness of our theoretical findings. 展开更多
关键词 Model predictive control Resilient control Platoon control Intelligent and connected vehicle Byzantine attacks
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Effects of connection types and elevated temperature on the impact behaviour of restrained beam in portal steel frame
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作者 Yu-Xu Guo Feng Xi +2 位作者 Ying-Hua Tan Feng Liu Ya-Chao Hu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期174-191,共18页
Based on the background of structural protection and Disaster Reduction Engineering, the dynamic behaviour and failure mechanism of restrained beams in portal steel frames in localised fire are investigated via experi... Based on the background of structural protection and Disaster Reduction Engineering, the dynamic behaviour and failure mechanism of restrained beams in portal steel frames in localised fire are investigated via experimental measurement and numerical simulation techniques. Comprehensive parametric studies are carried out to discuss the influence of end connection types, temperature, impact velocity,impact mass and span-to-depth ratio(SDR) on the dynamic response of the beams. The characteristics of deformation, internal force and energy distribution about the restrained beams and its joints are investigated. A temperature dependent criterion for evaluating the frame joint performance is proposed to measure the degree of performance degradation and impact resistance of the joint. The dynamic displacement amplification factor in different temperature environments are proposed for the different beam end constraint types and SDRs. Results of the experimental and numerical analysis show that the welded connection(WC) of three typical joint types is the strongest, and the extended endplate connection(EEC) is the weakest in terms of the impact resistance performance. With regard to the failure mode of the joint, the failure positions of the WC and the welded-bolted connection are located in the inner web of the column. Meanwhile, the EEC is located in the connection position between the beam and the endplate. Three different internal force stages and two obvious critical temperature boundaries of the restrained beams emerge with the increase in temperature, and they have significant characteristics in terms of deformation trend, internal force transfer and energy distribution. During the impact, a phenomenon known as “compression arch action” develops into “catenary action” with the increase in deflection in the frame beam mechanism. 展开更多
关键词 Restrained beam connection Temperature Impact Failure modes Internal force mechanism
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Shear Behaviors of Steel-Plate Connections for Timber-Concrete Composite Beams with Prefabricated Concrete Slabs
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作者 Benkai Shi Bowen Huang +2 位作者 Huifeng Yang Yongqing Dai Sijian Chen 《Journal of Renewable Materials》 SCIE EI 2023年第1期349-361,共13页
To promote the development of timber-concrete composite(TCC)structures,it is necessary to propose the assembly-type connections with high assembly efficiency and shear performances.This article presented the experimen... To promote the development of timber-concrete composite(TCC)structures,it is necessary to propose the assembly-type connections with high assembly efficiency and shear performances.This article presented the experimental results of the innovative steel-plate connections for TCC beams using prefabricated concrete slabs.The steel-plate connections consisted of the screws and the steel-plates.The steel-plates were partly embedded in the concrete slabs.The concrete slabs and the timber beams were connected by screws through the steel-plates.The parameters researched in this article included screw number,angle steel as the reinforcement for anchoring,and shallow notches on the timber surface to restrict the slip of the steel-plates.Experimental results were discussed in terms of failure modes,ultimate bearing capacities,and slip moduli.It was found that increasing the number of screws could lead to the obvious improvement on the ultimate bearing capacities and the slip moduli at the ultimate state;and the angle steel as the reinforcement showed the slight influence on the ultimate bearing capacities and the slip moduli.The application of the shallow notch can greatly improve the ultimate bearing capacities and the slip moduli.The calculation models for the ultimate bearing capacities and the slip moduli of the steel-plate connections with and without shallow notches were proposed,which showed good accuracy compared with the experimental results. 展开更多
关键词 Timber-concrete composites steel-plate connections PREFABRICATED shallow notches push-out tests
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The Effect of Self-Investment on Hoarding Tendency of Chinese College Students:Role of Psychological Connections
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作者 Xiangli Guan Yue Zhang +6 位作者 Yang Li Yaqi Zhang Jingjing Wang Xuejiao Li Mary C.Jobe Md Zahir Ahmed Oli Ahmed 《International Journal of Mental Health Promotion》 2023年第6期755-766,共12页
Because of factors such as energy and time one invests in an object,the stronger the connection,value,and reluc-tance to lose said object individual will have.Hoarding behavior arises when individuals incorporate a st... Because of factors such as energy and time one invests in an object,the stronger the connection,value,and reluc-tance to lose said object individual will have.Hoarding behavior arises when individuals incorporate a strong attachment with themselves to an object.The purpose of this study is to examine the effect of self-investment on hoarding tendency and the roles of possession-self link and liking level in this connection.A hypothetical model of the relationship between self-investment,possession-self link,liking level,and hoarding tendency was tested.A convenience sampling method was used to survey 450 college students in Yunnan Province on either a paper-based or online self-report scale.The data were collected using self-investment,possession-self link,and liking level questionnaires,as well as the Saving Inventory Revised.Results showed positive relationship between the study variables,ranging from 0.37 to 0.87.College students’self-investment had a direct positive pre-dictive effect on hoarding tendency;self-investment,in turn,indirectly predicted hoarding tendency through the mediating effect of possession-self link;and individual liking level of items had a moderating effect for self-invest-ment on the possession-self link.This study shows how self-investment affects the hoarding tendency of college students,and the results of this study also help demonstrate the value of self-investment and possession-self link in optimizing students’hoarding tendency and thus promoting good psychological status. 展开更多
关键词 Hoarding tendency self-investment psychological connections possession-self link liking level
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