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VIF-YOLO:A Visible-Infrared Fusion YOLO Model for Real-Time Human Detection in Dense Smoke Environments
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作者 Wenhe Chen Yue Wang +4 位作者 Shuonan Shen LeerHua Caixia Zheng Qi Pu Xundiao Ma 《Computers, Materials & Continua》 2026年第4期1463-1484,共22页
In fire rescue scenarios,traditional manual operations are highly dangerous,as dense smoke,low visibility,extreme heat,and toxic gases not only hinder rescue efficiency but also endanger firefighters’safety.Although ... In fire rescue scenarios,traditional manual operations are highly dangerous,as dense smoke,low visibility,extreme heat,and toxic gases not only hinder rescue efficiency but also endanger firefighters’safety.Although intelligent rescue robots can enter hazardous environments in place of humans,smoke poses major challenges for human detection algorithms.These challenges include the attenuation of visible and infrared signals,complex thermal fields,and interference frombackground objects,all ofwhichmake it difficult to accurately identify trapped individuals.To address this problem,we propose VIF-YOLO,a visible–infrared fusion model for real-time human detection in dense smoke environments.The framework introduces a lightweight multimodal fusion(LMF)module based on learnable low-rank representation blocks to end-to-end integrate visible and infrared images,preserving fine details while enhancing salient features.In addition,an efficient multiscale attention(EMA)mechanism is incorporated into the YOLOv10n backbone to improve feature representation under low-light conditions.Extensive experiments on our newly constructedmultimodal smoke human detection(MSHD)dataset demonstrate thatVIF-YOLOachievesmAP50 of 99.5%,precision of 99.2%,and recall of 99.3%,outperforming YOLOv10n by a clear margin.Furthermore,when deployed on the NVIDIA Jetson Xavier NX,VIF-YOLO attains 40.6 FPS with an average inference latency of 24.6 ms,validating its real-time capability on edge-computing platforms.These results confirm that VIF-YOLO provides accurate,robust,and fast detection across complex backgrounds and diverse smoke conditions,ensuring reliable and rapid localization of individuals in need of rescue. 展开更多
关键词 Fire rescue dense smoke environments human detection multimodal fusion YOLO
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An Unsupervised Online Detection Method for Foreign Objects in Complex Environments
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作者 YANG Xiaoyang YANG Yanzhu DENG Haiping 《Journal of Donghua University(English Edition)》 2026年第1期140-151,共12页
In modern industrial production,foreign object detection in complex environments is crucial to ensure product quality and production safety.Detection systems based on deep-learning image processing algorithms often fa... In modern industrial production,foreign object detection in complex environments is crucial to ensure product quality and production safety.Detection systems based on deep-learning image processing algorithms often face challenges with handling high-resolution images and achieving accurate detection against complex backgrounds.To address these issues,this study employs the PatchCore unsupervised anomaly detection algorithm combined with data augmentation techniques to enhance the system’s generalization capability across varying lighting conditions,viewing angles,and object scales.The proposed method is evaluated in a complex industrial detection scenario involving the bogie of an electric multiple unit(EMU).A dataset consisting of complex backgrounds,diverse lighting conditions,and multiple viewing angles is constructed to validate the performance of the detection system in real industrial environments.Experimental results show that the proposed model achieves an average area under the receiver operating characteristic curve(AUROC)of 0.92 and an average F1 score of 0.85.Combined with data augmentation,the proposed model exhibits improvements in AUROC by 0.06 and F1 score by 0.03,demonstrating enhanced accuracy and robustness for foreign object detection in complex industrial settings.In addition,the effects of key factors on detection performance are systematically analyzed,providing practical guidance for parameter selection in real industrial applications. 展开更多
关键词 foreign object detection unsupervised learning data augmentation complex environment BOGIE DATASET
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Impact of Data Processing Techniques on AI Models for Attack-Based Imbalanced and Encrypted Traffic within IoT Environments
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作者 Yeasul Kim Chaeeun Won Hwankuk Kim 《Computers, Materials & Continua》 2026年第1期247-274,共28页
With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comp... With the increasing emphasis on personal information protection,encryption through security protocols has emerged as a critical requirement in data transmission and reception processes.Nevertheless,IoT ecosystems comprise heterogeneous networks where outdated systems coexist with the latest devices,spanning a range of devices from non-encrypted ones to fully encrypted ones.Given the limited visibility into payloads in this context,this study investigates AI-based attack detection methods that leverage encrypted traffic metadata,eliminating the need for decryption and minimizing system performance degradation—especially in light of these heterogeneous devices.Using the UNSW-NB15 and CICIoT-2023 dataset,encrypted and unencrypted traffic were categorized according to security protocol,and AI-based intrusion detection experiments were conducted for each traffic type based on metadata.To mitigate the problem of class imbalance,eight different data sampling techniques were applied.The effectiveness of these sampling techniques was then comparatively analyzed using two ensemble models and three Deep Learning(DL)models from various perspectives.The experimental results confirmed that metadata-based attack detection is feasible using only encrypted traffic.In the UNSW-NB15 dataset,the f1-score of encrypted traffic was approximately 0.98,which is 4.3%higher than that of unencrypted traffic(approximately 0.94).In addition,analysis of the encrypted traffic in the CICIoT-2023 dataset using the same method showed a significantly lower f1-score of roughly 0.43,indicating that the quality of the dataset and the preprocessing approach have a substantial impact on detection performance.Furthermore,when data sampling techniques were applied to encrypted traffic,the recall in the UNSWNB15(Encrypted)dataset improved by up to 23.0%,and in the CICIoT-2023(Encrypted)dataset by 20.26%,showing a similar level of improvement.Notably,in CICIoT-2023,f1-score and Receiver Operation Characteristic-Area Under the Curve(ROC-AUC)increased by 59.0%and 55.94%,respectively.These results suggest that data sampling can have a positive effect even in encrypted environments.However,the extent of the improvement may vary depending on data quality,model architecture,and sampling strategy. 展开更多
关键词 Encrypted traffic attack detection data sampling technique AI-based detection IoT environment
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How do nanomaterials influence the spread of antibiotic resistance genes in aquatic environments?
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作者 Yun Bai Shengnan Li Shih-Hsin Ho 《Chinese Chemical Letters》 2026年第1期186-197,共12页
Antibiotic resistance genes(ARGs) are recognized as a primary threat to the sustainability of environment and human health in the 21^(st) century.Nanomaterials(NMs) have attracted substantial attention due to their un... Antibiotic resistance genes(ARGs) are recognized as a primary threat to the sustainability of environment and human health in the 21^(st) century.Nanomaterials(NMs) have attracted substantial attention due to their unique dimensions and structures.Unfortunately,emerging evidence suggests that NMs may facilitate the transmission of ARGs.It is crucial to elucidate how NMs affect the evolution and dissemination of ARGs.The current review comprehensively examines the role of NMs in the widespread transmission of ARGs in aquatic environments and the underlying mechanisms involved in the process.It aims to clarify the effects and mechanisms of NMs on the horizontal gene transfer processes that are associated with ARGs,including the enhancement of cell membrane permeability,the formation of nanopores on membranes,promotion of mutagenesis,and the generation of reactive oxygen species(ROSs).Furthermore,the trade-off between the removal of ARGs and horizontal transfer has been elucidated.The review aspires to guide future research directions,advance knowledge on the implications of NMs in the field of ARGs' transmission,and provide a theoretical foundation for the development of safer and more effective applications of NMs. 展开更多
关键词 Antibiotic resistance genes Antibiotic resistance bacteria NANOMATERIALS Horizontal gene transfer Aquatic environments
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Obtaining Electromagnetic Properties of Multi-Type Media in Realistic Environments:State-of-the-Art and Prospects 被引量:8
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作者 Guo Lantu Guan Ke +5 位作者 Liu Ting He Danping Zhang Haixia Zhu Qiuming Lu Jun Zhang Minggao 《China Communications》 2025年第1期25-40,共16页
To meet the requirements of electromagnetic(EM)theory and applied physics,this study presents an overview of the state-of-the-art research on obtaining the EM properties of media and points out potential solutions tha... To meet the requirements of electromagnetic(EM)theory and applied physics,this study presents an overview of the state-of-the-art research on obtaining the EM properties of media and points out potential solutions that can break through the bottlenecks of current methods.Firstly,based on the survey of three mainstream approaches for acquiring EM properties of media,we identify the difficulties when implementing them in realistic environments.With a focus on addressing these problems and challenges,we propose a novel paradigm for obtaining the EM properties of multi-type media in realistic environments.Particularly,within this paradigm,we describe the implementation approach of the key technology,namely“multipath extraction using heterogeneous wave propagation data in multi-spectrum cases”.Finally,the latest measurement and simulation results show that the EM properties of multi-type media in realistic environments can be precisely and efficiently acquired by the methodology proposed in this study. 展开更多
关键词 electromagnetic properties of media multi-type media parameter inversion ray tracing realistic environment
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A Secure Three-Factor Authenticated Key Agreement Scheme for Multi-Server Environment 被引量:2
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作者 Meichen Xia Shiliang Li Liu Liu 《Computers, Materials & Continua》 SCIE EI 2020年第9期1673-1689,共17页
Multi-server authenticated key agreement schemes have attracted great attention to both academia and industry in recent years.However,traditional authenticated key agreement schemes in the single-server environment ar... Multi-server authenticated key agreement schemes have attracted great attention to both academia and industry in recent years.However,traditional authenticated key agreement schemes in the single-server environment are not suitable for the multi-server environment because the user has to register on each server when he/she wishes to log in various servers for different service.Moreover,it is unreasonable to consider all servers are trusted since the server in a multi-server environment may be a semi-trusted party.In order to overcome these difficulties,we designed a secure three-factor multi-server authenticated key agreement protocol based on elliptic curve cryptography,which needs the user to register only once at the registration center in order to access all semi-trusted servers.The proposed scheme can not only against various known attacks but also provides high computational efficiency.Besides,we have proved our scheme fulfills mutual authentication by using the authentication test method. 展开更多
关键词 Authenticated key agreement three-factor multi-server authentication test method.
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Fluid-based moderate collision avoidance for UAV formation in 3-D low-altitude environments 被引量:1
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作者 Menghua ZHANG Honglun WANG +5 位作者 Zhiyu LI Yanxiang WANG Xianglun ZHANG Qiang TANG Shichao MA Jianfa WU 《Chinese Journal of Aeronautics》 2025年第6期533-551,共19页
Aiming to address the Unmanned Aerial Vehicle(UAV) formation collision avoidance problem in Three-Dimensional(3-D) low-altitude environments where dense various obstacles exist, a fluid-based path planning framework n... Aiming to address the Unmanned Aerial Vehicle(UAV) formation collision avoidance problem in Three-Dimensional(3-D) low-altitude environments where dense various obstacles exist, a fluid-based path planning framework named the Formation Interfered Fluid Dynamical System(FIFDS) with Moderate Evasive Maneuver Strategy(MEMS) is proposed in this study.First, the UAV formation collision avoidance problem including quantifiable performance indexes is formulated. Second, inspired by the phenomenon of fluids continuously flowing while bypassing objects, the FIFDS for multiple UAVs is presented, which contains a Parallel Streamline Tracking(PST) method for formation keeping and the traditional IFDS for collision avoidance. Third, to rationally balance flight safety and collision avoidance cost, MEMS is proposed to generate moderate evasive maneuvers that match up with collision risks. Comprehensively containing the time and distance safety information, the 3-D dynamic collision regions are modeled for collision prediction. Then, the moderate evasive maneuver principle is refined, which provides criterions of the maneuver amplitude and direction. On this basis, an analytical parameter mapping mechanism is designed to online optimize IFDS parameters. Finally, the performance of the proposed method is validated by comparative simulation results and real flight experiments using fixed-wing UAVs. 展开更多
关键词 Unmanned aerial vehicle Formation collision avoidance:3-D low-altitude environments Interfered fluid dynamical system 3-D dynamic collision region
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Weaknesses of a Dynamic ID Based Remote User Authentication Protocol for Multi-Server Environment
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作者 R. Madhusudhan Adireddi Praveen 《Journal of Computer and Communications》 2014年第4期196-200,共5页
Currently, smart card based remote user authentication schemes have been widely adopted due to their low cost and convenient portability. With the purpose of using various different internet services with single regis... Currently, smart card based remote user authentication schemes have been widely adopted due to their low cost and convenient portability. With the purpose of using various different internet services with single registration and to protect the users from being tracked, various dynamic ID based multi-server authentication protocols have been proposed. Recently, Li et al. proposed an efficient and secure dynamic ID based authentication protocol using smart cards. They claimed that their protocol provides strong security. In this paper, we have demonstrated that Li et al.’s protocol is vulnerable to replay attack, denial of service attack, smart card lost attack, eavesdropping attack and server spoofing attacks. 展开更多
关键词 AUTHENTICATION SMART CARD Dynamic ID multi-server environments PASSWORD
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A Bibliometric and Visualization Analysis of Forest Therapy Research:Investigating the Impact of Forest Environments on Human Physiological and Psychological Well-Being
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作者 Wei Hong Siyu Zhu +1 位作者 Donghui Lu Chiowa Ieong 《Journal of Environmental & Earth Sciences》 2025年第5期434-452,共19页
Human interaction with natural environments is gaining increasing attention in environmental sciences as research consistently shows that access to green spaces,clean air,and biodiversity plays a crucial role in enhan... Human interaction with natural environments is gaining increasing attention in environmental sciences as research consistently shows that access to green spaces,clean air,and biodiversity plays a crucial role in enhancing physical health,reducing stress,and improving overall well-being.This study conducts a bibliometric and visualization-based analysis of forest therapy research,emphasizing its physiological and psychological benefits.Using the Web of Science database,we identified and analyzed 414 studies from 1998 to 2023.Through CiteSpace and VOSviewer,we mapped these documents to examine research trends,publication networks,leading scholars and institutions,key journals,and thematic evolution.Findings indicate that forest therapy research is predominantly concentrated in East Asia,North America,Australia,and Europe,with strong collaborative networks among authors and institutions.The concentration of publications,research evolution,and keyword trends reflect the development of forest therapy research.The analysis further identifies sixteen research clusters and discusses two research themes:physiological and psychological effects.By analyzing how the natural environment contributes to human well-being,we provide a comprehensive and visually structured understanding of forest therapy as an intersection of environmental science,public health and well-being,and ecosystem conservation.Our findings offer a new perspective for future interdisciplinary research,emphasizing the need for well-designed clinical trials to substantiate forest therapy’s diverse health effects and its role in promoting sustainable interactions between human societies and natural environments. 展开更多
关键词 Forest Therapy CiteSpace VOSviewer environment Science
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Research on Anti-UAV Technology in Urban Environments
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作者 Lei Wang Haotian Chen +1 位作者 Tao Xi Lei Xia 《Journal of Electronic Research and Application》 2025年第5期143-149,共7页
With the rapid development of drone technology,drones are increasingly used in urban environments,but they also bring many security risks,such as illegal reconnaissance,smuggling,and terrorist attacks.Therefore,it is ... With the rapid development of drone technology,drones are increasingly used in urban environments,but they also bring many security risks,such as illegal reconnaissance,smuggling,and terrorist attacks.Therefore,it is of great significance to study the anti-UAV technology in the urban environment.This paper analyzes the advantages and disadvantages of existing technologies and their applicability in the urban environment from the aspects of UAV detection,identification,and countermeasures,and discusses the future development trend of anti-UAV technology,aiming to provide a reference for urban safety protection. 展开更多
关键词 Urban environment Anti-UAV technology DETECTION IDENTIFICATION COUNTERMEASURE
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Cold environments and health:proteomic analysis of health impacts
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作者 Hongquan Song Rui Zhang +2 位作者 Zixin Lu Xiaohui Jiao Jiaqun Yan 《Frigid Zone Medicine》 2025年第1期58-64,共7页
Background:Cold temperatures cause blood vessels to constrict,shallow breathing,and slight thickening of the blood.Working in extremely cold environments can have negative effects on health,yet there are currently no ... Background:Cold temperatures cause blood vessels to constrict,shallow breathing,and slight thickening of the blood.Working in extremely cold environments can have negative effects on health,yet there are currently no effective biomarkers to monitor these health conditions.Proteins are important intermediate phenotypes that can provide a theoretical basis for understanding disease pathophysiology.Proteins in the circulatory system reflect the physiological status of individuals,and plasma proteins have significant potential as biomarkers for various health conditions.Methods:In this study,we employed the Mendelian randomization(MR)method to analyze the effects of freezing temperatures on over 2900 plasma proteins.Subsequently,the selected plasma proteins were subjected to causal analysis in relation to 55 diseases,including respiratory disorders,cardiovascular diseases,various cancers,and oral diseases.The aim was to identify proteins that could serve as biomarkers for health status.Results:Our results indicate that cold environments may affect the concentrations of 78 plasma proteins.Further MR analysis revealed that nine of these plasma proteins are associated with the risk of respiratory disorders,cardiovascular diseases,various cancers,and oral diseases.Conclusion:These proteins show promise as biomarkers for monitoring the hazards and risks faced by individuals working in cold environments.These findings provide valuable insights into the biological mechanisms underlying occupational hazards. 展开更多
关键词 plasma protein BIOMARKER cold environment Mendelian randomization
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Multi-Agent Autonomous Collaborative Detection Method for Multi-Targets in Complex Fire Environments
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作者 Ke Li Haosheng Ye +4 位作者 Huairong Lin Runhan Xiao Biao Xu Bing Li Yao Yao 《Journal of Beijing Institute of Technology》 2025年第5期526-534,共9页
When a fire breaks out in a high-rise building,the occlusion of smoke and obstacles results in dearth of crucial information concerning people in distress,thereby creating a challenge in their detection.Given the rest... When a fire breaks out in a high-rise building,the occlusion of smoke and obstacles results in dearth of crucial information concerning people in distress,thereby creating a challenge in their detection.Given the restricted sensing range of a single unmanned aerial vehicle(UAV)cam-era,enhancing the target recognition rate becomes challenging without target information.To tackle this issue,this paper proposes a multi-agent autonomous collaborative detection method for multi-targets in complex fire environments.The objective is to achieve the fusion of multi-angle visual information,effectively increasing the target’s information dimension,and ultimately address-ing the problem of low target recognition rate caused by the lack of target information.The method steps are as follows:first,the you only look once version5(YOLOv5)is used to detect the target in the image;second,the detected targets are tracked to monitor their movements and trajectories;third,the person re-identification(ReID)model is employed to extract the appearance features of targets;finally,by fusing the visual information from multi-angle cameras,the method achieves multi-agent autonomous collaborative detection.The experimental results show that the method effectively combines the visual information from multi-angle cameras,resulting in improved detec-tion efficiency for people in distress. 展开更多
关键词 target detection multi-agent system fire environments detection
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Association between adverse home environments and symptoms in drugnaive children with attention-deficit/hyperactivity disorder
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作者 Chengchao Yu Wenqing Jiang Di Zhao 《General Psychiatry》 2025年第4期324-327,共4页
To the editor:Adverse home environments(AHE),characterised by family conflict,parental separation or dysfunctional parenting,are linked to negative mental health outcomes in children and adults.12 AHE disproportionate... To the editor:Adverse home environments(AHE),characterised by family conflict,parental separation or dysfunctional parenting,are linked to negative mental health outcomes in children and adults.12 AHE disproportionately affect children with neurodevelopmental disorders such as attention-deficit/hyperactivity disorder(ADHD),which is characterised by inattention,hyperactivity/impulsivity and functional impairments.3 Apart from core symptoms,including inattention and hyperactivity,disruptive behaviour disorders(DBD),such as oppositional defiant disorder(ODD)and conduct disorder(CD),may be associated with AHE.Conduct problems are risk factors for ODD.And CD has become a main concern for childhood mental health. 展开更多
关键词 conduct disorder attention deficit hyperactivity disorder adverse home environments home environments ahe characterised oppositional defiant disorder disruptive behavior disorders neurodevelopmental disorders
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Enhancing Military Visual Communication in Harsh Environments Using Computer Vision Techniques
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作者 Shitharth Selvarajan Hariprasath Manoharan +2 位作者 Taher Al-Shehari Nasser A Alsadhan Subhav Singh 《Computers, Materials & Continua》 2025年第8期3541-3557,共17页
This research investigates the application of digital images in military contexts by utilizing analytical equations to augment human visual capabilities.A comparable filter is used to improve the visual quality of the... This research investigates the application of digital images in military contexts by utilizing analytical equations to augment human visual capabilities.A comparable filter is used to improve the visual quality of the photographs by reducing truncations in the existing images.Furthermore,the collected images undergo processing using histogram gradients and a flexible threshold value that may be adjusted in specific situations.Thus,it is possible to reduce the occurrence of overlapping circumstances in collective picture characteristics by substituting grey-scale photos with colorized factors.The proposed method offers additional robust feature representations by imposing a limiting factor to reduce overall scattering values.This is achieved by visualizing a graphical function.Moreover,to derive valuable insights from a series of photos,both the separation and in-version processes are conducted.This involves analyzing comparison results across four different scenarios.The results of the comparative analysis show that the proposed method effectively reduces the difficulties associated with time and space to 1 s and 3%,respectively.In contrast,the existing strategy exhibits higher complexities of 3 s and 9.1%,respectively. 展开更多
关键词 Image enhancement visual information harsh environment computer vision
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Analysis of Measures for Strengthening the Protection of Meteorological Detection Environments in the New Era
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作者 Min GUO Yajing WANG Ziqi ZHANG 《Meteorological and Environmental Research》 2025年第4期6-8,共3页
Meteorological detection environments hold a fundamental and pioneering position in the development of meteorological undertakings,serving as the scientific support for accurately conducting weather forecast,professio... Meteorological detection environments hold a fundamental and pioneering position in the development of meteorological undertakings,serving as the scientific support for accurately conducting weather forecast,professional meteorological services,and disaster prevention and mitigation decision.The safety and stability of meteorological detection environments are of vital importance,and any behavior that damages or affects the detection environments is not allowed.In this paper,the factors influencing meteorological detection environments in the new era were explored,and measures to protect meteorological detection environments were proposed,such as strictly implementing the protection system of meteorological detection environments,lawfully investigating and punishing destructive behaviors,intensifying the publicity of the protection law,and enhancing public awareness. 展开更多
关键词 Meteorological observation environment Safety impact Protective measures
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Adaptive Vibration-Driven Tensegrity in Unstructured Environments
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作者 Ruhe Mei Ruizhi Liu +1 位作者 Yafeng Wang Xian Xu 《Journal of Bionic Engineering》 2025年第5期2354-2366,共13页
Tensegrity structures,embodying the principles of continuous tensioning and discrete compression,have emerged as fundamental frameworks in locomotive soft robotics for navigating uneven and unpredictable environments,... Tensegrity structures,embodying the principles of continuous tensioning and discrete compression,have emerged as fundamental frameworks in locomotive soft robotics for navigating uneven and unpredictable environments,owing to their flexible and resilient traits.By means of a straightforward and cost-effective method to achieve structure-driven,vibration-driven tensegrity shows great potential,particularly in tasks demanding random exploration.However,the design guidance for vibration-driven tensegrity and their performance evaluation in unstructured terrain remain unrevealed due to the complex dynamics of the structure.This paper presents a small six-bar tensegrity robot,driven by wireless vibration motors,designed for deployment in disaster rescue and search scenarios.Finite element simulation is used to investigate how structural characteristics,excitation parameters,and the arrangement of motors affect the kinematic performance of this tensegrity system.A prototype of the six-bar tensegrity robot with three motors located on the lower ends of the three lower struts is designed and manufactured after the numerical simulations.A simple control policy which adjusts the motion of the tensegrity robot by turning on or off the motors on different locations is proposed.The prototype with and without the control policy is tested in man-made environments of various complexity.It shows that the ability and efficiency of the tensegrity robot in exploring unstructured environments is significantly enhanced by the proposed control policy.It is believed that the potential of the vibration-driven tensegrity robot could be further exploited by integrating multi-source sensors and more intelligent control policies. 展开更多
关键词 Finite element simulation Parametric design TENSEGRITY Unstructured environment VIBRATION
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A multi-parametric path planning framework utilizing airspace visibility graphs for urban battlefield environments
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作者 Sidao Chen Xuejun Zhang +1 位作者 Zuyao Zhang Jianxiang Ma 《Defence Technology(防务技术)》 2025年第9期112-126,共15页
Urban combat environments pose complex and variable challenges for UAV path planning due to multidimensional factors,such as static and dynamic obstructions as well as risks of exposure to enemy detection,which threat... Urban combat environments pose complex and variable challenges for UAV path planning due to multidimensional factors,such as static and dynamic obstructions as well as risks of exposure to enemy detection,which threaten flight safety and mission success.Traditional path planning methods typically depend solely on the distribution of static obstacles to generate collision-free paths,without accounting for constraints imposed by enemy detection and strike capabilities.Such a simplified approach can yield safety-compromising routes in highly complex urban airspace.To address these limitations,this study proposes a multi-parameter path planning method based on reachable airspace visibility graphs,which integrates UAV performance constraints,environmental limitations,and exposure risks.An innovative heuristic algorithm is developed to balance operational safety and efficiency by both exposure risks and path length.In the case study set in a typical mixed-use urban area,analysis of airspace visibility graphs reveals significant variations in exposure risk at different regions and altitudes due to building encroachments.Path optimization results indicate that the method can effectively generate covert and efficient flight paths by dynamically adjusting the exposure index,which represents the likelihood of enemy detection,and the path length,which corresponds to mission execution time. 展开更多
关键词 UAV Path planning Urban battlefield environment Airspace visibility graph ISOVIST
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CO hydrogenation conversion driven by micro-environments of active sites over iron carbide catalysts
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作者 Nan Song Xingxing Li +6 位作者 Ebtihal Abograin Wenyao Chen Junbo Cao Jing Zhang De Chen Xuezhi Duan Xinggui Zhou 《Green Energy & Environment》 2025年第2期367-373,共7页
Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of CO hydrogenation conversion process is still a great ch... Essentially clearing the structure-activity relationship between iron carbide catalysts involving multiple active centers to understand the reaction mechanism of CO hydrogenation conversion process is still a great challenge.Here,two main micro-environment factors,namely electronic properties and geometrical effects were found to have an integrated effect on the mechanism of CO hydrogenation conversion,involving active sites on multiple crystal phases.The Bader charge of the surface Fe atoms on the active sites had a guiding effect on the CO activation pathway,while the spatial configuration of the active sites greatly affected the energy barriers of CO activation.Although the defective surfaces were more conducive to CO activation,the defective sites were not the only sites to dissociate CO,as CO always tended to dissociate in a wider area.This synergistic effect of the micro-environment also occurred during the CO conversion process.Surface C atoms on relatively flat configurations were more likely to form methane,while the electronic properties of the active sites could effectively describe the C-C coupling process,as well as distinguish the coupling mechanisms. 展开更多
关键词 MICRO-environMENT CO hydrogenation conversion Electronic property Local environment Synergistic effect
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Construction Robotics in Extreme Environments:From Earth to Space
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作者 Ke You Cheng Zhou +1 位作者 Lieyun Ding Yuxiang Wang 《Engineering》 2025年第12期107-124,共18页
Extreme environments are unstructured and change rapidly,making human exploration in unfamiliar areas difficult.Construction robotics can help reduce risks to human safety and property in these environments by integra... Extreme environments are unstructured and change rapidly,making human exploration in unfamiliar areas difficult.Construction robotics can help reduce risks to human safety and property in these environments by integrating digital technology and artificial intelligence.This technology has the potential to significantly improve the quality and efficiency of construction,making it a key area for future research.Extreme environments include hazardous work sites,polluted areas,and harsh natural conditions.Our review of construction robotics in these settings highlights several knowledge gaps.We focused on four main areas:mechanism design,perception,planning,and control.Our analysis reveals challenges in practical applications,such as creating adaptable mechanisms,accurately perceiving changing environments,planning for unstructured sites,and optimizing control models.Future research should explore:biomimetic designs inspired by nature,multimodal data fusion for perception,adaptive planning strategies,and hybrid control models that combine data-driven and mechanism-based approaches. 展开更多
关键词 Construction robotics Extreme environment Mechanism design PERCEPTION PLANNING CONTROL Artificial intelligence
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Biomimetic Manipulation of Smooth Solid Surfaces for Vacuum High-Temperature and Vibration Environments
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作者 Jiachun Zhang Tingwei Huo +5 位作者 Yuanming Ji Haozhen Zhan Shixun Fu Jianming Wu Xipeng Wang Keju Ji 《Journal of Bionic Engineering》 2025年第2期755-766,共12页
In the fields of optoelectronics and semiconductors, reliable fixation and handling of brittle materials (glass, wafer, etc.) in high-temperature, vacuum, and vibration environments face particular technical challenge... In the fields of optoelectronics and semiconductors, reliable fixation and handling of brittle materials (glass, wafer, etc.) in high-temperature, vacuum, and vibration environments face particular technical challenges. These challenges include the inability of suction cups in a vacuum, the residue of chemical adhesives, and the easy damage of mechanical clamping. In this paper, fluorine-based bionic adhesive pads (FBAPs) obtained using molding technology to imitate gecko micropillar arrays are presented. FBAPs inhibit the substantial decay of adhesive properties at high temperatures and provide stable and reliable performance in vacuum and vibration environments. The results demonstrated that the decayed force values of the normal and tangential strength of the FBAP were only 9.01% and 5.82% of the planar samples when warmed up to 300℃ from 25℃, respectively. In a vacuum, all FBAPs exhibit less than 20% adhesion attenuation, and in a vibrational environment, they can withstand accelerations of at least 4.27 g. The design of the microstructure arrays enables the realization of efficient and non-destructive separation through mechanical rotation or blowing. It provides a bionic material basis for the fixation of brittle materials on smooth surfaces under complex environments and for transportation automation. 展开更多
关键词 High-temperature environments van der Waals forces Microstructure arrays FLUOROELASTOMER Interfacial manipulation
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