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Identification of Visibility Level for Enhanced Road Safety under Different Visibility Conditions:A Hierarchical Clustering-Based Learning Model
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作者 Asmat Ullah Yar Muhammad +4 位作者 Bakht Zada Korhan Cengiz Nikola Ivkovic Mario Konecki Abid Yahya 《Computers, Materials & Continua》 2025年第11期3767-3786,共20页
Low visibility conditions,particularly those caused by fog,significantly affect road safety and reduce drivers’ability to see ahead clearly.The conventional approaches used to address this problem primarily rely on i... Low visibility conditions,particularly those caused by fog,significantly affect road safety and reduce drivers’ability to see ahead clearly.The conventional approaches used to address this problem primarily rely on instrument-based and fixed-threshold-based theoretical frameworks,which face challenges in adaptability and demonstrate lower performance under varying environmental conditions.To overcome these challenges,we propose a real-time visibility estimation model that leverages roadside CCTV cameras to monitor and identify visibility levels under different weather conditions.The proposedmethod begins by identifying specific regions of interest(ROI)in the CCTVimages and focuses on extracting specific features such as the number of lines and contours detected within these regions.These features are then provided as an input to the proposed hierarchical clusteringmodel,which classifies them into different visibility levels without the need for predefined rules and threshold values.In the proposed approach,we used two different distance similaritymetrics,namely dynamic time warping(DTW)and Euclidean distance,alongside the proposed hierarchical clustering model and noted its performance in terms of numerous evaluation measures.The proposed model achieved an average accuracy of 97.81%,precision of 91.31%,recall of 91.25%,and F1-score of 91.27% using theDTWdistancemetric.We also conducted experiments for other deep learning(DL)-based models used in the literature and compared their performances with the proposed model.The experimental results demonstrate that the proposedmodel ismore adaptable and consistent compared to themethods used in the literature.The proposedmethod provides drivers real-time and accurate visibility information and enhances road safety during low visibility conditions. 展开更多
关键词 CCTV images road safety and security visibility level estimation hierarchical clustering learning feature extraction safe and secure transportation
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Safe flight corridor constrained sequential convex programming for efficient trajectory generation of fixed-wing UAVs 被引量:2
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作者 Jing SUN Guangtong XU +2 位作者 Zhu WANG Teng LONG Jingliang SUN 《Chinese Journal of Aeronautics》 2025年第1期537-550,共14页
Generating dynamically feasible trajectory for fixed-wing Unmanned Aerial Vehicles(UAVs)in dense obstacle environments remains computationally intractable.This paper proposes a Safe Flight Corridor constrained Sequent... Generating dynamically feasible trajectory for fixed-wing Unmanned Aerial Vehicles(UAVs)in dense obstacle environments remains computationally intractable.This paper proposes a Safe Flight Corridor constrained Sequential Convex Programming(SFC-SCP)to improve the computation efficiency and reliability of trajectory generation.SFC-SCP combines the front-end convex polyhedron SFC construction and back-end SCP-based trajectory optimization.A Sparse A^(*)Search(SAS)driven SFC construction method is designed to efficiently generate polyhedron SFC according to the geometric relation among obstacles and collision-free waypoints.Via transforming the nonconvex obstacle-avoidance constraints to linear inequality constraints,SFC can mitigate infeasibility of trajectory planning and reduce computation complexity.Then,SCP casts the nonlinear trajectory optimization subject to SFC into convex programming subproblems to decrease the problem complexity.In addition,a convex optimizer based on interior point method is customized,where the search direction is calculated via successive elimination to further improve efficiency.Simulation experiments on dense obstacle scenarios show that SFC-SCP can generate dynamically feasible safe trajectory rapidly.Comparative studies with state-of-the-art SCP-based methods demonstrate the efficiency and reliability merits of SFC-SCP.Besides,the customized convex optimizer outperforms off-the-shelf optimizers in terms of computation time. 展开更多
关键词 Fixed-wing unmanned aerial vehicle Efficient trajectory planning safe flight corridor Sequential convex programming Customized convex optimizer
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Acetabular Component Positioning and Risk of Dislocation in Hip Arthroplasty: Is Lewinnek’s Safe Zone Truly Safe?
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作者 Oliver Damiani Meyer Luis Henrique Zambra Wink +3 位作者 Walter Brandt Iserhard Carlos Roberto Schwartsmann Anthony Kerbes Yépez Leandro de Freitas Spinelli 《Open Journal of Orthopedics》 2025年第2期47-53,共7页
Objective: The present research aims to determine if adherence to the Lewinnek safe zone, when exclusively considered, constitutes a pivotal element for ensuring stability in the context of total hip arthroplasty. Thi... Objective: The present research aims to determine if adherence to the Lewinnek safe zone, when exclusively considered, constitutes a pivotal element for ensuring stability in the context of total hip arthroplasty. This is done by examining the acetabular placement in instances of hip dislocation after total hip arthroplasty (THA). Methodology: The authors searched 2653 patient records from 2015 to 2022 looking for patients who had total hip arthroplasty at our facility. For the analysis, 23 patients were culled from 64 individuals who exhibited post-THA dislocations, employing a stringent exclusion criterion, and the resultant acetabular angulation and anteversion were quantified utilizing PEEKMED software (Peek Health S.A., Portugal) upon radiographic evidence. Results: Within the operational timeframe, from the cohort of 2653 subjects, 64 presented with at least a singular incident of displacement. Post-exclusion criterion enforcement, 23 patients were eligible for inclusion. Of these, 10 patients conformed to the safe zone demarcated by Lewinnek for both inclination and anteversion angles, while 13 exhibited deviations from the prescribed anteversion and/or inclination benchmarks. Conclusion: Analysis of the 23 patients reveals that 13 did not confirm to be in the safe zone parameters for anteversion and/or inclination, whereas 10 were within the safe zone as per Lewinnek’s guidelines. This investigative review, corroborated by extant literature, suggests that the isolated consideration of the Lewinnek safe zone does not suffice as a solitary protective factor. It further posits that additional variables are equally critical as acetabular positioning and mandate individual assessment. 展开更多
关键词 Acetabular Component Positioning DISLOCATION Hip Arthroplasty Lewinnek’s safe Zone
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A Low-Collision and Efficient Grasping Method for Manipulator Based on Safe Reinforcement Learning
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作者 Qinglei Zhang Bai Hu +2 位作者 Jiyun Qin Jianguo Duan Ying Zhou 《Computers, Materials & Continua》 2025年第4期1257-1273,共17页
Grasping is one of the most fundamental operations in modern robotics applications.While deep rein-forcement learning(DRL)has demonstrated strong potential in robotics,there is too much emphasis on maximizing the cumu... Grasping is one of the most fundamental operations in modern robotics applications.While deep rein-forcement learning(DRL)has demonstrated strong potential in robotics,there is too much emphasis on maximizing the cumulative reward in executing tasks,and the potential safety risks are often ignored.In this paper,an optimization method based on safe reinforcement learning(Safe RL)is proposed to address the robotic grasping problem under safety constraints.Specifically,considering the obstacle avoidance constraints of the system,the grasping problem of the manipulator is modeled as a Constrained Markov Decision Process(CMDP).The Lagrange multiplier and a dynamic weighted mechanism are introduced into the Proximal Policy Optimization(PPO)framework,leading to the development of the dynamic weighted Lagrange PPO(DWL-PPO)algorithm.The behavior of violating safety constraints is punished while the policy is optimized in this proposed method.In addition,the orientation control of the end-effector is included in the reward function,and a compound reward function adapted to changes in pose is designed.Ultimately,the efficacy and advantages of the suggested method are proved by extensive training and testing in the Pybullet simulator.The results of grasping experiments reveal that the recommended approach provides superior safety and efficiency compared with other advanced RL methods and achieves a good trade-off between model learning and risk aversion. 展开更多
关键词 safe reinforcement learning(safe RL) manipulator grasping obstacle avoidance constraints lagrange multiplier dynamic weighted
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Application Value of Bundle Management in Safe Nursing Care for Patients with Autoimmune Encephalitis
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作者 Ying Cui 《Journal of Clinical and Nursing Research》 2025年第4期149-154,共6页
Objective:To explore the application effect of bundle management in the safe nursing of patients with autoimmune encephalitis.Methods:Seventy-five patients with autoimmune encephalitis who met the inclusion criteria i... Objective:To explore the application effect of bundle management in the safe nursing of patients with autoimmune encephalitis.Methods:Seventy-five patients with autoimmune encephalitis who met the inclusion criteria in our hospital from January 2024 to June 2024 were randomly divided into two groups:an observation group of 39 patients and a control group of 36 patients.The control group received routine nursing care,while the observation group implemented a bundle management strategy based on routine nursing care.Safety nursing outcomes,clinical symptom improvement time,hospital stay,and neurologic function recovery were observed in both groups.Results:The incidence of adverse events in the observation group was 12.82%,significantly lower than the 33.33%in the control group,with a statistically significant difference(P<0.05).There was no statistically significant difference in restraint usage and ICU transfer rates between the two groups(P>0.05).The clinical symptom improvement time,hospital stay,and neurologic function recovery in the observation group were significantly better than those in the control group,with a statistically significant difference(P<0.05).Conclusion:Through the bundle management model,effective connections can be ensured in various aspects of treatment and rehabilitation for patients with autoimmune encephalitis,providing patients with comprehensive and multi-level nursing services and improving their overall satisfaction and treatment effectiveness. 展开更多
关键词 Bundle management Autoimmune Encephalitis safe nursing Clinical effect
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Historical Safe Haven in Shanghai
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作者 LU JIAJUN 《China Today》 2025年第9期36-41,共6页
IN the Shanghai Jewish Refugees Museum,a beautiful handbag is waiting for its owner in a display cabinet.The handbag belongs to a Jewish couple.When they sought refuge in Shanghai during World War II,they pawned the h... IN the Shanghai Jewish Refugees Museum,a beautiful handbag is waiting for its owner in a display cabinet.The handbag belongs to a Jewish couple.When they sought refuge in Shanghai during World War II,they pawned the handbag to Jin Wenzhen’s grandfather in exchange for their child’s medical expenses.He lent the couple the cash equivalent of one month’s revenue from his rice shop,but then never saw them again. 展开更多
关键词 rice shop Jewish refugees SHANGHAI historical safe haven pawned handbag medical expenses World War II
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Influence mechanism and calculation of the minimum safe thickness of waterproof rock mass in karst tunnels
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作者 AN Pengtao LI Maoxiang +1 位作者 ZHANG Wenjun LIU Xiong 《Journal of Mountain Science》 2025年第2期695-709,共15页
Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more random.In order to explore the influence rule of karst cave location on the ... Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more random.In order to explore the influence rule of karst cave location on the minimum safe thickness of water-proof rock mass,a simplified calculation model of water-proof rock mass thickness when the karst cave is located at any location around the tunnel is established,and the influence of multiple factors on the overall stability of water-proof rock mass is considered.Based on the cusp catastrophe theory,the analytical expressions for the safety thickness of waterproof rock mass are derived.Based on the finite difference principle,the analytical expressions of the safety thickness of water-proof rock mass are verified.In order to improve the application range of the analytical formula derived in this paper,the analytical formula is optimized based on the instability principle differences between the simplified calculation model and the elastic compressive bar.The research results show that the necessary condition solution is more applicable and much safer than the sufficient condition solution.Tectonic stress,rock beam length and karst cave water pressure are significantly positively correlated with the safe thickness of the waterproof rock mass.The calculated results of the semioptimized formula and the unoptimized formula are constant values,independent of the karst cave location.While the calculated results of the fully optimized formula are variable values,correlated with the karst cave location,the thickness of the waterproof rock mass gradually decreases as the karst cave location moves from the top of the tunnel to the bottom of the tunnel.The unoptimized formula does not consider the influence of the lateral force of the rock beam,and is not suitable for the working condition with large lateral force,the calculation results of the semi-optimized formula and the fully optimized formula are not very different and are biased to safety,so it can be given priority. 展开更多
关键词 Tunnel engineering Water inrush disaster safe thickness Waterproof rock mass Concealed karst cave
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Bye microplastics! Ocean-safe straws that break down naturally
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作者 Zhao Xinhua 《China Textile》 2025年第3期26-27,共2页
Against the backdrop of the global push for environmental protection and the reduction of plastic pollution,the research and development of alternatives to daily disposable plastic products such as straws have become ... Against the backdrop of the global push for environmental protection and the reduction of plastic pollution,the research and development of alternatives to daily disposable plastic products such as straws have become a hot topic in the environmental protection field.Traditional plastic straws are difficult to degrade,imposing a severe burden on the environment.Meanwhile,existing alternatives like paper straws and PLA(polylactic acid)straws also have numerous drawbacks. 展开更多
关键词 traditional plastic straws paper straws ocean safe straws plastic pollution alternatives disposable plastics microplastics natural breakdown environmental protection
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Safe and healthy working environment for occupational health:advancing evidence-informed policy-making
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作者 Min Zhang 《Global Health Journal》 2025年第2期63-64,F0002,共3页
With the civilization and modernization of human society,occupational health has emerged as a fundamental goal of social justice,as highlighted in the United Nations'Sustainable Development Goals(SDGs)since 2016.S... With the civilization and modernization of human society,occupational health has emerged as a fundamental goal of social justice,as highlighted in the United Nations'Sustainable Development Goals(SDGs)since 2016.Specifically,"SDG Goal 1:No Poverty","SDG 3:Good Health and Well-being",and"SDG 8:Decent Work and Economic Growth",are interconnected with other SDGs to support the pursuit of occupational health. 展开更多
关键词 modernization CIVILIZATION safe working environment development goals sdgs social justice occupational health evidence informed policy making healthy working environment
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A Game-Theoretic Approach to Safe Crowd Evacuation in Emergencies
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作者 Maria Gul Imran Ali Khan +9 位作者 Gohar Zaman Atta Rahman Jamaluddin Mir Sardar Asad Ali Biabani May IssaAldossary Mustafa Youldash Ashraf Saadeldeen Maqsood Mahmud Asiya Abdus Salam Dania Alkhulaifi 《Computers, Materials & Continua》 SCIE EI 2024年第4期1631-1657,共27页
Obstacle removal in crowd evacuation is critical to safety and the evacuation system efficiency. Recently, manyresearchers proposed game theoreticmodels to avoid and remove obstacles for crowd evacuation. Game theoret... Obstacle removal in crowd evacuation is critical to safety and the evacuation system efficiency. Recently, manyresearchers proposed game theoreticmodels to avoid and remove obstacles for crowd evacuation. Game theoreticalmodels aim to study and analyze the strategic behaviors of individuals within a crowd and their interactionsduring the evacuation. Game theoretical models have some limitations in the context of crowd evacuation. Thesemodels consider a group of individuals as homogeneous objects with the same goals, involve complex mathematicalformulation, and cannot model real-world scenarios such as panic, environmental information, crowds that movedynamically, etc. The proposed work presents a game theoretic model integrating an agent-based model to removethe obstacles from exits. The proposed model considered the parameters named: (1) obstacle size, length, andwidth, (2) removal time, (3) evacuation time, (4) crowd density, (5) obstacle identification, and (6) route selection.The proposed work conducts various experiments considering different conditions, such as obstacle types, obstacleremoval, and several obstacles. Evaluation results show the proposed model’s effectiveness compared with existingliterature in reducing the overall evacuation time, cell selection, and obstacle removal. The study is potentially usefulfor public safety situations such as emergency evacuations during disasters and calamities. 展开更多
关键词 safe crowd evacuation public safety EMERGENCY transition probability COOPERATION
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Study on the Safety and Prevention Technology of Coal Mining under the River in Xingyuan Coal Mine
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作者 Abdoulaye Sylla Wenbing Guo 《Open Journal of Geology》 CAS 2024年第3期339-402,共64页
Coal mining-induced surface subsidence poses significant ecological and infrastructural challenges, necessitating a comprehensive study to ensure safe mining practices, particularly in underwater conditions. This proj... Coal mining-induced surface subsidence poses significant ecological and infrastructural challenges, necessitating a comprehensive study to ensure safe mining practices, particularly in underwater conditions. This project aims to address the extensive impact of coal mining on the environment, infrastructure, and overall safety, focusing on the Shigong River area above the working face. The study employs qualitative and quantitative analyses, along with on-site engineering measurements, to gather data on crucial parameters such as coal seam characteristics, roof rock lithology, thickness, water resistance, and structural damage degree. The research encompasses a multidisciplinary approach, involving mining, geology, hydrogeology, geophysical exploration, rock mechanics, mine surveying, and computational mathematics. The importance of effective safety measures and prevention techniques is emphasized, laying the foundation for research focused on the Xingyun coal mine. The brief concludes by highlighting the potential economic and social benefits of this project and its contribution to valuable experience for future subsea coal mining. 展开更多
关键词 Coal Mining-Induced Surface Subsidence Ecological and Infrastructural Challenges safe Mining Practices Underwater Conditions Multidisciplinary Approach safety Measures Prevention Techniques
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Soil inorganic amendments produce safe rice by reducing the transfer of Cd and increasing key amino acids in brown rice 被引量:1
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作者 Fanyi Kong Shenggao Lu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第2期121-132,共12页
The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human health.In our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosag... The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human health.In our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosages were applied to produce safe rice and improve the quality of rice in Cd-contaminated paddy.With the increased application of SIA,Cd content in iron plaque on rice root significantly increased,the transfer of Cd from rice root to grain significantly decreased,and then Cd content in brown rice decreased synchronously.The vitro digestibility of Cd in brown rice was estimated by a physiologically based extraction test.Results showed that more than 70%of Cd in brown rice could be digested by simulated gastrointestinal juice.Based on the total and digestible Cd contents in brown rice to evaluate the health risk,the application of 2.25 ton SIA/ha could produce safe rice in acidic slightly Cd-contaminated paddy soils.The amino acids(AAs)in brown rice were determined by high-performance liquid chromatography.The contents of 5 key AAs(KAAs)that actively respond to environmental changes increased significantly with the increased application of SIA.The structural equation model indicated that KAAs could be affected by the Cd translocation capacity from rice root to grain,and consequently altered the ratio of indigestible Cd in brown rice.The formation of indigestible KAAs-Cd complexes by combining KAAs(phenylalanine,leucine,histidine,glutamine,and asparagine)with Cd in brown rice could be considered a potential mechanism for reducing the digestibility of Cd. 展开更多
关键词 Cadmium digestibility Soil inorganic amendments safe rice Amino acid Priming effect Health risk
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Enhanced Memory-Safe Linux Security Modules (eLSMs) for Improving Security of Docker Containers for Data Centers 被引量:1
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作者 Juan Martinez Delbugio Vijay K. Madisetti 《Journal of Software Engineering and Applications》 2024年第5期259-269,共11页
The adoption of Docker containers has revolutionized software deployment by providing a lightweight and efficient way to isolate applications in data centers. However, securing these containers, especially when handli... The adoption of Docker containers has revolutionized software deployment by providing a lightweight and efficient way to isolate applications in data centers. However, securing these containers, especially when handling sensitive data, poses significant challenges. Traditional Linux Security Modules (LSMs) such as SELinux and AppArmor have limitations in providing fine-grained access control to files within containers. This paper presents a novel approach using eBPF (extended Berkeley Packet Filter) to implement a LSM that focuses on file-oriented access control within Docker containers. The module allows the specification of policies that determine which programs can access sensitive files, providing enhanced security without relying solely on the host operating system’s major LSM. 展开更多
关键词 DOCKER LSM MAC RUST Memory safe Languages
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A cross-sectional study to assess medication safety,knowledge,attitude,and practices regarding nutrition and medication among pregnant women
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作者 Gauthami R Bipin Shaji +3 位作者 Twinkle MJS Krishnapriya Radhakrishnan Reshma Kolar Juno Jerold Joel 《Asian pacific Journal of Reproduction》 CAS 2024年第3期115-119,共5页
Objective:To assess pregnant women's knowledge,attitude,and practice regarding nutrition and medication usage,analyse the prescribing pattern,and categorize them based on the Food and Drug Administration(FDA)guide... Objective:To assess pregnant women's knowledge,attitude,and practice regarding nutrition and medication usage,analyse the prescribing pattern,and categorize them based on the Food and Drug Administration(FDA)guidelines.Methods:A cross-sectional study was conducted with 264 pregnant women in the obstetrics and gynaecology department of a tertiary care hospital from October 2022 to August 2023.A knowledge,attitude,and practice(KAP)questionnaire was prepared in English language by the researchers and validated by an expert panel consisting of 12 members.The validated questionnaire was then translated into regional languages,Kannada and Malayalam.The reliability of the questionnaire was assessed with test-retest method with a representative sample population of 30 subjects(10 subjects for each language).The subjects'knowledge,attitude,and practice were evaluated using the validated KAP questionnaire.The safety of the medication was assessed using the FDA drug safety classification for pregnancy.Results:The mean scores for nutritional and medication usage knowledge,attitude,and practice were 4.14±1.15,4.50±1.09,and 3.00±1.47,respectively.Among 30 prescribed medications,3 belong to category A(no risk in human studies),8 belong to category B(no risk in animal studies),18 belong to category C(risk cannot be ruled out)and 1 drug is not classified.A significant association was observed between medication knowledge and practice(r=0.159,P=0.010).Conclusions:Most of the study population knows the need to maintain good dietary and medication practices during pregnancy.Counselling pregnant women regarding diet and medication usage is crucial in maternal care. 展开更多
关键词 PREGNANCY NUTRITION MEDICATION KNOWLEDGE Practice safe medication
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A Dual-Task Learning Approach for Bearing Anomaly Detection and State Evaluation of Safe Region
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作者 Yuhua Yin Zhiliang Liu +1 位作者 Bin Guo Mingjian Zuo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期229-241,共13页
Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal phases.Within the ostensibly stable healthy phase,the reliance o... Predictive maintenance has emerged as an effective tool for curbing maintenance costs,yet prevailing research predominantly concentrates on the abnormal phases.Within the ostensibly stable healthy phase,the reliance on anomaly detection to preempt equipment malfunctions faces the challenge of sudden anomaly discernment.To address this challenge,this paper proposes a dual-task learning approach for bearing anomaly detection and state evaluation of safe regions.The proposed method transforms the execution of the two tasks into an optimization issue of the hypersphere center.By leveraging the monotonicity and distinguishability pertinent to the tasks as the foundation for optimization,it reconstructs the SVDD model to ensure equilibrium in the model’s performance across the two tasks.Subsequent experiments verify the proposed method’s effectiveness,which is interpreted from the perspectives of parameter adjustment and enveloping trade-offs.In the meantime,experimental results also show two deficiencies in anomaly detection accuracy and state evaluation metrics.Their theoretical analysis inspires us to focus on feature extraction and data collection to achieve improvements.The proposed method lays the foundation for realizing predictive maintenance in a healthy stage by improving condition awareness in safe regions. 展开更多
关键词 Bearing condition monitoring Anomaly detection safe region Support vector data description
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Risk-Informed Model-Free Safe Control of Linear Parameter-Varying Systems
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作者 Babak Esmaeili Hamidreza Modares 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第9期1918-1932,共15页
This paper presents a risk-informed data-driven safe control design approach for a class of stochastic uncertain nonlinear discrete-time systems.The nonlinear system is modeled using linear parameter-varying(LPV)syste... This paper presents a risk-informed data-driven safe control design approach for a class of stochastic uncertain nonlinear discrete-time systems.The nonlinear system is modeled using linear parameter-varying(LPV)systems.A model-based probabilistic safe controller is first designed to guarantee probabilisticλ-contractivity(i.e.,stability and invariance)of the LPV system with respect to a given polyhedral safe set.To obviate the requirement of knowing the LPV system model and to bypass identifying its open-loop model,its closed-loop data-based representation is provided in terms of state and scheduling data as well as a decision variable.It is shown that the variance of the closedloop system,as well as the probability of safety satisfaction,depends on the decision variable and the noise covariance.A minimum-variance direct data-driven gain-scheduling safe control design approach is presented next by designing the decision variable such that all possible closed-loop system realizations satisfy safety with the highest confidence level.This minimum-variance approach is a control-oriented learning method since it minimizes the variance of the state of the closed-loop system with respect to the safe set,and thus minimizes the risk of safety violation.Unlike the certainty-equivalent approach that results in a risk-neutral control design,the minimum-variance method leads to a risk-averse control design.It is shown that the presented direct risk-averse learning approach requires weaker data richness conditions than existing indirect learning methods based on system identification and can lead to a lower risk of safety violation.Two simulation examples along with an experimental validation on an autonomous vehicle are provided to show the effectiveness of the presented approach. 展开更多
关键词 Data-driven control linear parameter-varying systems probabilistic control safe control
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Smart materials for safe lithium-ion batteries against thermal runaway
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作者 Yu Ou Pan Zhou +5 位作者 Wenhui Hou Xiao Ma Xuan Song Shuaishuai Yan Yang Lu Kai Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期360-392,共33页
In recent years,the new energy storage system,such as lithium ion batteries(LIBs),has attracted much attention.In order to meet the demand of industrial progress for longer cycle life,higher energy density and cost ef... In recent years,the new energy storage system,such as lithium ion batteries(LIBs),has attracted much attention.In order to meet the demand of industrial progress for longer cycle life,higher energy density and cost efficiency,a quantity of research has been conducted on the commercial application of LIBs.However,it is difficult to achieve satisfying safety and cycling performance simultaneously.There may be thermal runaway(TR),external impact,overcharge and overdischarge in the process of battery abuse,which makes the safety problem of LIBs more prominent.In this review,we summarize recent progress in the smart safety materials design towards the goal of preventing TR of LIBs reversibly from different abuse conditions.Benefiting from smart responsive materials and novel structural design,the safety of LIBs can be improved a lot.We expect to provide a comprehensive reference for the development of smart and safe lithium-based battery materials. 展开更多
关键词 Lithium ion batteries(LIBs) Thermal runaway(TR) Smart materials safe batteries Solid electrolyte interface(SEI)
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无人机辅助物联网中基于Safe Actor-Critic的信息年龄最小化研究
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作者 魏宪鹏 付芳 张志才 《测试技术学报》 2024年第1期71-78,共8页
无人机作为一种新的通信设备,有望在物联网数据采集、监控等业务中发挥关键作用。为保证所采集数据的时效性,利用信息年龄来衡量无人机从物联网设备接收到的数据新鲜度。通过联合优化无人机轨迹和无人机与物联网设备的关联策略以最小化... 无人机作为一种新的通信设备,有望在物联网数据采集、监控等业务中发挥关键作用。为保证所采集数据的时效性,利用信息年龄来衡量无人机从物联网设备接收到的数据新鲜度。通过联合优化无人机轨迹和无人机与物联网设备的关联策略以最小化信息年龄加权和,并保证无人机累积飞行能量消耗满足预算要求。由于上述问题同时受短期和长期约束条件的限制,将问题建模为受约束的马尔可夫决策过程(CMDP),并利用Safe Actor-Critic来求解。仿真结果表明,所提算法在最小化信息年龄的同时,能有效保证能量预算。 展开更多
关键词 无人机 信息年龄 物联网 safe Actor-Critic
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Patient Safety Efforts in Tanzania: A Rapid Review of Two-Decades Efforts (2002-2022) to Inform Interventions towards Attainment of 2030 Targets
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作者 Joseph C. Hokororo Michael Habtu +12 位作者 Radenta P. Bahegwa Ruth R. Ngowi Yohanes S. Msigwa Mbwana M. Degeh Erick S. Kinyenje Omary A. Nassoro Laura E. Marandu Chrisogone J. German Edwin Mkwama Bushi Lugoba Grace E. Saguti Zabulon Yoti Eliudi S. Eliakimu 《Advances in Infectious Diseases》 CAS 2022年第3期466-495,共30页
Introduction: The need to address the problem of patient safety has been a focus of World Health Assembly (WHA) meetings of 2002, 2019 and 2021. The 2019 WHA Resolution urged the Member States to take action on patien... Introduction: The need to address the problem of patient safety has been a focus of World Health Assembly (WHA) meetings of 2002, 2019 and 2021. The 2019 WHA Resolution urged the Member States to take action on patient safety. We aimed to review patient safety efforts in Tanzania from 2002 to 2022 to inform improvement efforts towards the 2030 target. Methods: A rapid literature review was conducted between January 2002 and April 2022. We searched Google, PubMed and PubMed Central in April and May 2022 using the following search terms: PubMed—“patient safety Tanzania”, “blood safety in Tanzania”, “safe surgery Tanzania”, and “healthcare-associated infections Tanzania”;Google—“blood safety in Tanzania”, injection safety in Tanzania”, “infection prevention and control”, “radiation safety in health facilities in Tanzania”;and PubMed Central—“injection safety in Tanzania. Results: The search identified 4160 articles, of which 4053 were removed in initial screening;21 were duplicates, giving 86 relevant articles for full screening. Of the 86 articles, 04 were removed after the full screening, hence remaining with 82 articles. Among the 82 eligible articles, 27 are on IPC, 26 on safe surgery, 12 on blood safety, 07 on radiation safety, 06 on injection safety, and 02 on medication safety. One article was relevant to—blood safety, IPC and injection safety;and one article was relevant to—IPC and injection safety. Conclusion: Most of the eligible literature was on IPC and safe surgery, followed by blood safety, radiation safety, injection safety and medication safety. The literature on IPC has highlighted the need to strengthen efforts to address AMR. Findings from the implementation of the safe surgery 2020 intervention warrants for its scale-up to other zones. There is a need to strengthen hemovigilance and pharmacovigilance functions;and strengthen quality management and assurance systems and regulatory functions to ensure radiation safety. 展开更多
关键词 Patient safety safe Surgery Infection Prevention and Control Medication safety Radiation safety
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一种描述逻辑与DL-safe规则复合逻辑中的规则抽取方法 被引量:1
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作者 张阔 李涓子 +1 位作者 唐杰 王克宏 《计算机科学》 CSCD 北大核心 2005年第8期121-123,共3页
OWL本体描述语言包含相对丰富的概念定义符,但提供的关系定义符描述能力则较差。将 OWL与规则相结合是克服这种表达能力限制的一种常用方法。Motik提出了一种可判定的方法,将SHIQ(D)描述逻辑与规则结合,所结合的规则限定在一种叫做DL-s... OWL本体描述语言包含相对丰富的概念定义符,但提供的关系定义符描述能力则较差。将 OWL与规则相结合是克服这种表达能力限制的一种常用方法。Motik提出了一种可判定的方法,将SHIQ(D)描述逻辑与规则结合,所结合的规则限定在一种叫做DL-safe规则的范围内。本文提出了一种抽取DL-safe规则的方法,方法利用SHIQ(D)逻辑中的UNION定义符满足一些规则在前件中包含析取逻辑运算符的需求,从而扩展了规则的描述能力。 展开更多
关键词 描述逻辑 DL-safe规则 OWL 语义网 抽取方法 safe 复合 概念定义 能力限制 逻辑运算符
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