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Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling Systems
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作者 Sabrina Meddah Sid Ahmed Tadjer +3 位作者 Abdelhakim Idir Kong Fah Tee Mohamed Zinelabidine Doghmane Madjid Kidouche 《Structural Durability & Health Monitoring》 EI 2025年第1期77-103,共27页
Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emp... Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is required.This study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling equipment.The study specifically investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency stick-slip.These events not only hinder the efficiency of drilling but also lead to exhaustion and harm to the system’s components since they are difficult to be detected and controlled in real time.The study investigates the dynamic interactions of these vibrations,specifically in their high-frequency modes,usingfield data obtained from measurement while drilling.Thefindings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem performance.The obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control systems.Therefore,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect damage.Moreover,by exploiting thesefindings,the assessment of structural resilience in rotary drilling systems can be enhanced.Furthermore,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efficiency of rotary drilling systems in the petroleum industry. 展开更多
关键词 Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis field data analysis
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Forensic Analysis of Cyberattacks in Electric Vehicle Charging Systems Using Host-Level Data
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作者 Salam Al-E’mari Yousef Sanjalawe +4 位作者 Budoor Allehyani Ghader Kurdi Sharif Makhadmeh Ameera Jaradat Duaa Hijazi 《Computers, Materials & Continua》 2025年第11期3289-3320,共32页
Electric Vehicle Charging Systems(EVCS)are increasingly vulnerable to cybersecurity threats as they integrate deeply into smart grids and Internet ofThings(IoT)environments,raising significant security challenges.Most... Electric Vehicle Charging Systems(EVCS)are increasingly vulnerable to cybersecurity threats as they integrate deeply into smart grids and Internet ofThings(IoT)environments,raising significant security challenges.Most existing research primarily emphasizes network-level anomaly detection,leaving critical vulnerabilities at the host level underexplored.This study introduces a novel forensic analysis framework leveraging host-level data,including system logs,kernel events,and Hardware Performance Counters(HPC),to detect and analyze sophisticated cyberattacks such as cryptojacking,Denial-of-Service(DoS),and reconnaissance activities targeting EVCS.Using comprehensive forensic analysis and machine learning models,the proposed framework significantly outperforms existing methods,achieving an accuracy of 98.81%.The findings offer insights into distinct behavioral signatures associated with specific cyber threats,enabling improved cybersecurity strategies and actionable recommendations for robust EVCS infrastructure protection. 展开更多
关键词 Electric vehicle charging systems forensic analysis CYBERSECURITY host security cyber-physical systems
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Optimal Planning of Multiple PV-DG in Radial Distribution Systems Using Loss Sensitivity Analysis and Genetic Algorithm
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作者 A. Elkholy 《Journal of Power and Energy Engineering》 2025年第2期1-22,共22页
This paper introduces an optimized planning approach for integrating photovoltaic as distributed generation (PV-DG) into the radial distribution power systems, utilizing exhaustive load flow (ELF), loss sensitivity fa... This paper introduces an optimized planning approach for integrating photovoltaic as distributed generation (PV-DG) into the radial distribution power systems, utilizing exhaustive load flow (ELF), loss sensitivity factor (LSF), genetic algorithms (GA) methods, and numerical method based on LSF. The methodology aims to determine the optimal allocation and sizing of multiple PV-DG to minimize power loss through time series power flow analysis. An approach utilizing continuous sensitivity analysis is developed and inherently leverages power flow and loss equations to compute LSF of all buses in the system towards employing a dynamic PV-DG model for more accurate results. The algorithm uses a numerical grid search method to optimize PV-DG placement in a power distribution system, focusing on minimizing system losses. It combines iterative analysis, sensitivity assessment, and comprehensive visualization to identify and present the optimal PV-DG configurations. The present-ed algorithms are verified through co-simulation framework combining MATLAB and OpenDSS to carry out analysis for 12-bus radial distribution test system. The proposed numerical method is compared with other algorithms, such as ELF, LSF methods, and Genetic Algorithms (GA). Results show that the proposed numerical method performs well in comparison with LSF and ELF solutions. 展开更多
关键词 Photovoltaic systems Distributed Generation Multiple Allocation and Sizing Power Losses Radial Distribution System Genetic Algorithm
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Analysis of Two Irrigation Water Pumping Systems on the Taddis Valley Site: Solar Kit and Motor Pump Unit (GMP) in Tahoua (Niger)
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作者 Yerima Bako Djibo Aboubacar Guero Yadji Bori Haoua 《World Journal of Engineering and Technology》 2025年第1期39-48,共10页
The study was carried out in the Tahoua region at the market gardening sites of the Taddis 1 and 2 valley. Small-scale pumping irrigation is one of the most interesting uses of solar energy. The objective of this stud... The study was carried out in the Tahoua region at the market gardening sites of the Taddis 1 and 2 valley. Small-scale pumping irrigation is one of the most interesting uses of solar energy. The objective of this study is to carry out a comparative analysis of two dewatering pumping systems (Solar Kit and GMP) for water mobilization on a certain number of criteria such as sustainable use, economic aspect and performance. To achieve this, the adapted methodology consisted first of all in the development of a data collection tool in the field. Then flow measurements, estimation of fuel consumption, pressure height, etc., were carried out. Thus, the data collection involved a sample of 120 irrigators who had to use the two (2) types of pumping systems. The collected data were analyzed and processed with appropriate software. The results of the study show that the two pumping systems studied have strengths and constraints. Thus, the solar pumping system has a significant investment cost, very low maintenance and a low operating cost. On the other hand, the system with a generator has a relatively low investment cost (25 to 30 times less than solar), but a relatively high operating, upkeep and maintenance cost. He adds that these assets and constraints must be taken into consideration when an investment is made. This study shows that 74% of producers use GMP compared to 26% who use the Solar Kit. But in practice, the Solar Kit is more reliable for producers from the point of view of planted area, environmental management and investment costs, supply of fuel and lubricant. These results indicate better performance of the solar pumping system compared to GMP at the study sites. 展开更多
关键词 Market Gardening Sites Pumping systems Solar Kit GMP Taddis and Tahoua Valley
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Comparative Analysis of Mineral Rights Licensing Systems in Tanzania and Uganda
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作者 Mudan Huang 《Proceedings of Business and Economic Studies》 2025年第4期391-401,共11页
In order to promote the development of the mineral industry in their countries,Tanzania and Uganda have revised their mining acts in recent years,and the reform of the mineral rights licensing system is one of the key... In order to promote the development of the mineral industry in their countries,Tanzania and Uganda have revised their mining acts in recent years,and the reform of the mineral rights licensing system is one of the key points.This paper is intended to make a comparative analysis of the two countries’mineral rights licensing systems in terms of the main body of approval,approval time,approval information,approval conditions and application fees.Through comparison,it can be seen that the two countries focus on the role of the government in the mineral rights licensing,jurisdiction is more centralized,access system is fairer,the review is more stringent,and the provisions are clearer and more concise.On the whole,Tanzania’s mineral rights licensing system is more detailed and standardized than Uganda’s,and is more operational in practice.In addition to exploring the advantages of the two countries’mineral rights licensing system,this paper also summarizes and analyzes the shortcomings of the two countries’mineral rights licensing system,how to verify the review of information in the two countries’mineral rights licensing system,how to effectively supervise the activities after licensing,and how to continue to deepen the reform of the two countries’ministries of mines and minerals,which are responsible for the important task of strengthening the administrative capacity and improving the efficiency of the administration,is still an important issue that deserves continuous and in-depth study for the two countries.For both countries,this is still a topic that deserves continuous and in-depth research.Through the comparative analysis of the Tanzanian and Ugandan mineral rights licensing systems,this paper clearly demonstrates the similarities and differences between the two systems as well as their advantages and disadvantages,which can provide decision-making references for relevant mining investments and help investors more comprehensively assess the legal environment,policy risks and operating costs of mining development in the two countries,so as to optimize their investment strategies and reduce compliance risks. 展开更多
关键词 Mineral rights Licensing systems Tanzania Uganda
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Analysis of Renewable Energy Absorption and Economic Feasibility in Multi-Energy Complementary Systems under Spot Market Conditions
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作者 Xiuyun Wang Zipeng Zhang +1 位作者 Chuang Liu Guoliang Bian 《Energy Engineering》 2025年第2期577-619,共43页
As the power system transitions to a new green and low-carbon paradigm,the penetration of renewable energy in China’s power system is gradually increasing.However,the variability and uncertainty of renewable energy o... As the power system transitions to a new green and low-carbon paradigm,the penetration of renewable energy in China’s power system is gradually increasing.However,the variability and uncertainty of renewable energy output limit its profitability in the electricity market and hinder its market-based integration.This paper first constructs a wind-solar-thermalmulti-energy complementary system,analyzes its external game relationships,and develops a bi-level market optimization model.Then,it considers the contribution levels of internal participants to establish a comprehensive internal distribution evaluation index system.Finally,simulation studies using the IEEE 30-bus system demonstrate that the multi-energy complementary system stabilizes nodal outputs,enhances the profitability of market participants,and promotes the market-based integration of renewable energy. 展开更多
关键词 Multi-energy complementary systems spot market two-layer optimization new energy consumption
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LOKIBASE:The Device for Seismic Isolation of Pallet Racking Systems-Optimization Analysis
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作者 Marco Ferrari 《Journal of Civil Engineering and Architecture》 2025年第8期361-372,共12页
LOKIBASE is a non-linear isolator/dissipator device to protect pallet racking systems against the earthquake.LOKIBASE consists of the following main components:(1)two slider devices on which a rubber membrane is set u... LOKIBASE is a non-linear isolator/dissipator device to protect pallet racking systems against the earthquake.LOKIBASE consists of the following main components:(1)two slider devices on which a rubber membrane is set up(LOKI devices).LOKI devices are linear displacement dependent ones;(2)a cylindrical beam damper(“CANDLE”device).The“CANDLE”device is a non-linear displacement dependent one;(3)two anti-lifting devices(“UP-LIFT”devices);(4)a fuse plug(see www.lokibasedevice.com).The main work which is the purpose of the paper,is the optimization of the behavior of an isolator/dissipator device to mitigate the seismic action on special structures,where the stiffness values are very different in the main cross-aisle and down-aisle directions.Under seismic action,in these structures it is very important to reduce the value of the forces at the Limit state for the safeguard of human life(SLV)in the down-aisle direction as much as possible and simultaneously to use the highest damping value allowed by the building rules to reduce the LOKIBASE displacement at the Limit state for collapse prevention(SLC)in the cross-aisle direction.The goal was achieved through a cylindrical device made of stainless steel(AISI304)with an optimized shape,under large displacement during seismic action. 展开更多
关键词 LOKIBASE “CANDLE” pallet racking systems cylindrical beam damper holed cylindrical beam damper
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Status analysis on sputtering and erosion evaluation methods of ion optic systems
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作者 Long MIAO Tongxun YANG +3 位作者 Zhengxi ZHU Chang LU Zhiwen WU Ningfei WANG 《Chinese Journal of Aeronautics》 2025年第1期254-270,共17页
In the past few decades,ion engines have been widely used in deep-space propulsion and satellite station-keeping.The aim of extending the thruster lifetime is still one of the most important parts during the design st... In the past few decades,ion engines have been widely used in deep-space propulsion and satellite station-keeping.The aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion engine.As one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming failures.In this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid assembly.The advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are analyzed.Three different types of experimental methods of grid assembly erosion patterns are compared.The analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid assembly.Consequently,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime. 展开更多
关键词 Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation
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Plant extracts with antioxidant and hepatoprotective benefits for liver health:A bibliometric analysis of drug delivery systems
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作者 Gaurav Mittal Prashanth A +4 位作者 Arkadeep Dhali Roshan Prasad Yogesh S Khulud Mahmood Nurani Mihnea-Alexandru Găman 《World Journal of Gastroenterology》 2025年第18期84-100,共17页
BACKGROUND The rising global burden of liver diseases,such as non-alcoholic fatty liver disease and liver fibrosis,has necessitated innovative therapeutic approaches.Plant-based therapies,recognized for their anti-inf... BACKGROUND The rising global burden of liver diseases,such as non-alcoholic fatty liver disease and liver fibrosis,has necessitated innovative therapeutic approaches.Plant-based therapies,recognized for their anti-inflammatory and antioxidant properties,have shown promising effects.However,poor bioavailability limits their clinical application.AIM To map global research trends,key contributors,and emerging themes in plant-based therapies combined with advanced drug delivery systems for liver health.METHODS Using the Scopus database,645 documents were retrieved and analyzed using bibliometric tools Biblioshiny and VOSviewer.Analysis focused on publication trends,geographical contributions,and advancements in drug delivery technologies,including nanoparticles,liposomes,and polymeric micelles.Metrics such as publication growth rate,authorship collaboration,and thematic clustering were assessed.RESULTS The dataset spans 43 years(1981-2024),with an annual growth rate of 11.09%in the number of publications.Research output is dominated by China(33%),followed by the United States(24%)and India(18%).Collaborative studies accounted for 24.34%of publications,with an average of 5.81 co-authors per document.Key innovations include nanoparticle encapsulation of curcumin and silymarin,improving bioavailability by up to 85%.Highly cited studies demonstrated the antioxidant,anti-inflammatory,and anti-fibrotic properties of these compounds.For instance,curcumin nanoparticles showed a 70%improvement in solubility,and silymarin liposomal formulations enhanced therapeutic efficiency by 62%.Thematic analysis revealed a transition from basic clinical observations to molecular and pharmacokinetic research,with a focus on oxidative stress mitigation and hepatoprotection.CONCLUSION This study highlights the growing synergy between plant-based therapies and advanced drug delivery systems,with significant contributions from Asian and Western countries.Future efforts should prioritize clinical trials,standardization of plant extract formulations,and interdisciplinary approaches to maximize therapeutic outcomes.The findings provide a foundation for integrating plant-derived compounds into evidence-based hepatological therapies,addressing critical challenges in bioavailability and safety. 展开更多
关键词 Liver health Plant extracts Drug delivery PHARMACOKINETICS HEPATOPROTECTION BIOAVAILABILITY Bibliometric analysis
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An Analysis of the Chemical Stress Field Under Potentiostatic Intermittent Titration Techniques for Interfacial Reaction-Controlled Systems
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作者 Kaikai Li Shichen Wang +1 位作者 Xiuling Shi Yan Huang 《Acta Mechanica Solida Sinica》 2025年第3期508-516,共9页
The potentiostatic intermittent titration technique(PITT)is widely used to determine the diffusion coefficient of ions in electrode materials for rechargeable batteries such as lithium-ion or sodium-ion batteries,pred... The potentiostatic intermittent titration technique(PITT)is widely used to determine the diffusion coefficient of ions in electrode materials for rechargeable batteries such as lithium-ion or sodium-ion batteries,predicated on the assumption that the insertion/extraction of ions in the host materials is governed by diffusion.However,in practical scenarios,the electrochemical process might be dominated by interfacial reaction kinetics rather than diffusion.The present work derives analytical equations for electric current by considering the finite interfacial reaction kinetics and small overpotentials during PITT measurements and further studies the chemical stress field induced by the interfacial reaction-controlled ion insertion.The exchange current density(j_(0))can be ascertained using the analytical equation,which dictates the magnitude and decay rate of the electric current during a PITT process.The electric current decays more rapidly,and consequently,the lithium concentration reaches equilibrium faster for larger values of j_(0).The magnitude of the chemical stress is independent of j_(0) but depends on the overpotential. 展开更多
关键词 Chemical stress Potentiostatic intermittent titration techniques Interfacial reaction-controlled systems Exchange current density Lithium diffusion
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Research on the Development Strategies of Realtime Data Analysis and Decision-support Systems
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作者 Wei Tang 《Journal of Electronic Research and Application》 2025年第2期204-210,共7页
With the advent of the big data era,real-time data analysis and decision-support systems have been recognized as essential tools for enhancing enterprise competitiveness and optimizing the decision-making process.This... With the advent of the big data era,real-time data analysis and decision-support systems have been recognized as essential tools for enhancing enterprise competitiveness and optimizing the decision-making process.This study aims to explore the development strategies of real-time data analysis and decision-support systems,and analyze their application status and future development trends in various industries.The article first reviews the basic concepts and importance of real-time data analysis and decision-support systems,and then discusses in detail the key technical aspects such as system architecture,data collection and processing,analysis methods,and visualization techniques. 展开更多
关键词 Real-time data analysis Decision-support system Big data System architecture Data processing Visualization technology
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Economic and carbon emission analysis of two typical denitrification systems for sintering process in the iron and steel industry
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作者 Jianguo Yang Mengdan Wu +6 位作者 Jian Gao Hanxiao Liu Miaomiao Cheng Xuecheng Wu Xiang Gao Kunzan Qiu Yang Yang 《Journal of Environmental Sciences》 2025年第10期79-90,共12页
The transition of the Chinese iron and steel industry to ultralow emissions has accelerated the development of denitrification technologies.Considering the existing dual carbon targets,carbon emissions must be conside... The transition of the Chinese iron and steel industry to ultralow emissions has accelerated the development of denitrification technologies.Considering the existing dual carbon targets,carbon emissions must be considered as a critical indicator when comparing denitrification systems.Consequently,this study provided a comprehensive cost-benefit model for denitrification in the steel industry,encompassing additional carbon emissions resulting from the implementation of denitrification systems.Activated-carbon adsorption and selective catalytic reduction(SCR)systems are two efficient techniques for controlling NOx emissions during sintering.Based on thismodel,a cost-benefit analysis of these two typical systems was conducted,and the results indicated that the unit flue-gas abatement costs of SCR and activated-carbon adsorption systems were 0.00275 and 0.0126 CNY/m^(3),and the unit flue-gas abatement benefits were 0.0072 and 0.0179 CNY/m^(3),respectively.Additionally,the effect of operational characteristics on operating costs,including duration and material prices,was analyzed.When treating the flue gas,the two systems released 0.0020 and 0.0060 kg/m^(3) of carbon dioxide,respectively.The primary sources of carbon emissions from the SCR and activated-carbon adsorption systems are the production of reducing agents and system operations,respectively.Furthermore,considering the features of the activated carbon adsorption system for simultaneous desulfurization,a SCR-wet flue gas desulfurization(WFGD)technology route was developed for comparison with the activated carbon adsorption system. 展开更多
关键词 Iron and steel industry Denitrification technology Carbon emission Cost-benefit model Economic analysis
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Collaborative State Estimation for Coupled Transmission and Distribution Systems Based on Clustering Analysis and Equivalent Measurement Modeling
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作者 Hao Jiao Xinyu Liu +4 位作者 Chen Wu Chunlei Xu Zhijun Zhou Ye Chen Guoqiang Sun 《Energy Engineering》 2025年第7期2977-2992,共16页
With the continuous expansion of the power system scale and the increasing complexity of operational mode,the interaction between transmission and distribution systems is becoming more and more significant,placing hig... With the continuous expansion of the power system scale and the increasing complexity of operational mode,the interaction between transmission and distribution systems is becoming more and more significant,placing higher requirements on the accuracy and efficiency of the power system state estimation to address the challenge of balancing computational efficiency and estimation accuracy in traditional coupled transmission and distribution state estimation methods,this paper proposes a collaborative state estimation method based on distribution systems state clustering and load model parameter identification.To resolve the scalability issue of coupled transmission and distribution power systems,clustering is first carried out based on the distribution system states.As the data and models of the transmission system and distribution systems are not shared.For the transmission system,equating the power transmitted from the transmission system to the distribution system is the same as equating the distribution system.Further,the power transmitted from the transmission system to different types of distribution systems is equivalent to different polynomial equivalent load models.Then,a parameter identification method is proposed to obtain the parameters of the equivalent load model.Finally,a transmission and distribution collaborative state estimation model is constructed based on the equivalent load model.The results of the numerical analysis show that compared with the traditional master-slave splitting method,the proposed method significantly enhances computational efficiency while maintaining high estimation accuracy. 展开更多
关键词 Transmission and distribution collaboration cluster analysis parameter identification equivalent load state estimation
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Investigation of mechanical strength and deformation properties of Y25 bogie suspension systems by finite element analysis
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作者 Celalettin Baykara 《Railway Sciences》 2025年第6期685-710,共26页
Purpose–This paper aims to offer a novel viewpoint for improving performance and reliability by developing and optimizing suspension components in a Y25 bogie through material optimization based on wheel–rail intera... Purpose–This paper aims to offer a novel viewpoint for improving performance and reliability by developing and optimizing suspension components in a Y25 bogie through material optimization based on wheel–rail interactions under variable load and track conditions.Design/methodology/approach–The suspension system,a critical component ensuring adaptation to road and load conditions in all vehicle types,is especially vital in heavy freight and passenger trains.In this context,the suspension set of the Y25 bogie–commonly used in T€urkiye and Europe–was modelled using CATIAV5,and stress analyses have been performed by way of ANSYS using the finite element analysis(FEA)method.E300-520-M cast steel was selected for the bogie frame,while two different spring steels,61SiCr7 and 51CrV4,were considered for the suspension springs.The modeled system was subjected to numerical analysis under loading conditions.The resulting stresses and displacements were compared with the mechanical properties of the selected materials to validate the design.Findings–The results demonstrate that the mechanical strength and deformation characteristics of the suspension components vary according to the applied external loads.The stress and displacement responses of the system were found to be within the allowable limits of the selected materials,confirming the structural integrity and reliability of the design.The suspension set is deemed suitable for the prescribed material and environmental conditions,suggesting potential for practical application in real-world rail systems.Originality/value–This research contributes to the design and optimization of bogie suspension systems using advanced CAD/CAE tools.It thinks that the material selection and numerical validation approach presented here can guide future designs in heavy load rail applications and potentially improve both safety and performance. 展开更多
关键词 Finite element analysis Y25 railway bogie Suspension system Railway vehicles Wheel-rail interaction
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Health Assessment and Driving Force Analysis of Cropland Systems in Typical Black Soil Region of Northeast China from 2003 to 2023
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作者 TIAN Xinyu JIANG Hailing +3 位作者 LUO Niu ZHANG Shuhan YU Hailin ZHANG Jingyi 《Chinese Geographical Science》 2025年第3期564-580,共17页
The health of cropland systems is directly related to the degree of food security guarantee,and the‘quantity-quality-ecology as a whole’protection is of great significance for maintaining the health of cropland syst... The health of cropland systems is directly related to the degree of food security guarantee,and the‘quantity-quality-ecology as a whole’protection is of great significance for maintaining the health of cropland systems.Taking the typical black soil region in Northeast China(TBSN)as an example,this paper combined the concept of‘quantity-quality-ecology as a whole’protection with crop-land systems health,constructed a health assessment model for cropland systems,and used Google Earth Engine to conduct a quantitat-ive analysis of the temporal and spatial evolution of cropland systems health in TBSN during 2003–2023.By coupling the geographical detector and the Multi-scale Geographically Weighted Regression(MGWR)model,the driving factors of cropland health changes were explored.The study finds that during the research period,the health status of cropland systems in TBSN showed a slight downward trend,and the distribution pattern of cropland systems health gradually shifted from‘better in the east’to‘high in the northeast and low in the southwest’.Changes in average annual sunshine duration,relative humidity,and precipitation had a significant impact on the spa-tial differentiation of cropland systems health in the early stages,and were considered as dominant factors.Meanwhile,the influence of dual dominant factors in the natural environment on cropland systems health is increasing.Furthermore,the MGWR model performed better in revealing the complex relationships between natural and social factors and changes in cropland systems health,demonstrating the significant spatial heterogeneity of the impacts of natural environment and human activities on cropland systems health.The re-search can provide scientific guidance for the sustainable development of TBSN and formulate more precise and effective cropland pro-tection policies. 展开更多
关键词 cropland systems health Google Earth Engine(GEE) Multi-scale Geographically Weighted Regression(MGWR)model Geographical Detector typical black soil region Northeast China
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Analysis and Design of Time-Delay Impulsive Systems Subject to Actuator Saturation 被引量:1
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作者 Chenhong Zhu Xiuping Han Xiaodi Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期196-204,共9页
This paper investigates the exponential stability and performance analysis of nonlinear time-delay impulsive systems subject to actuator saturation. When continuous dynamics is unstable, under some conditions, it is s... This paper investigates the exponential stability and performance analysis of nonlinear time-delay impulsive systems subject to actuator saturation. When continuous dynamics is unstable, under some conditions, it is shown that the system can be stabilized by a class of saturated delayed-impulses regardless of the length of input delays. Conversely, when the system is originally stable, it is shown that under some conditions, the system is robust with respect to sufficient small delayed-impulses. Moreover, the design problem of the controller with the goal of obtaining a maximized estimate of the domain of attraction is formulated via a convex optimization problem. Three examples are provided to demonstrate the validity of the main results. 展开更多
关键词 Delayed impulses impulsive control impulsive disturbance nonlinear systems SATURATION
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Frequency-domain analysis of fluid-structure interaction in aircraft hydraulic pipeline systems: numerical and experimental studies 被引量:2
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作者 Yang DENG Zongxia JIAO Yuanzhi XU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2024年第8期605-617,共13页
The fluid-structure interaction(FSI)in aircraft hydraulic pipeline systems is of great concern because of the damage it causes.To accurately predict the vibration characteristic of long hydraulic pipelines with curved... The fluid-structure interaction(FSI)in aircraft hydraulic pipeline systems is of great concern because of the damage it causes.To accurately predict the vibration characteristic of long hydraulic pipelines with curved segments,we studied the frequency-domain modeling and solution method for FSI in these pipeline systems.Fourteen partial differential equations(PDEs)are utilized to model the pipeline FSI,considering both frequency-dependent friction and bending-flexibility modification.To address the numerical instability encountered by the traditional transfer matrix method(TMM)in solving relatively complex pipelines,an improved TMM is proposed for solving the PDEs in the frequency domain,based on the matrix-stacking strategy and matrix representation of boundary conditions.The proposed FSI model and improved solution method are validated by numerical cases and experiments.An experimental rig of a practical hydraulic system,consisting of an aircraft engine-driven pump,a Z-shaped aero-hydraulic pipeline,and a throttle valve,was constructed for testing.The magnitude ratio of acceleration to pressure is introduced to evaluate the theoretical and experimental results,which indicate that the proposed model and solution method are effective in practical applications.The methodology presented in this paper can be used as an efficient approach for the vibrational design of aircraft hydraulic pipeline systems. 展开更多
关键词 Fluid-structure interaction(FSI) Frequency-domain analysis Aircraft hydraulic pipeline Pipeline vibration Transfer matrix method(TMM)
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Modeling,Simulation,and Risk Analysis of Battery Energy Storage Systems in New Energy Grid Integration Scenarios 被引量:2
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作者 Xiaohui Ye Fucheng Tan +4 位作者 Xinli Song Hanyang Dai Xia Li Shixia Mu Shaohang Hao 《Energy Engineering》 EI 2024年第12期3689-3710,共22页
Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy s... Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy storage system(BESS).However,the current modeling of grid-connected BESS is overly simplistic,typically only considering state of charge(SOC)and power constraints.Detailed lithium(Li)-ion battery cell models are computationally intensive and impractical for real-time applications and may not be suitable for power grid operating conditions.Additionally,there is a lack of real-time batteries risk assessment frameworks.To address these issues,in this study,we establish a thermal-electric-performance(TEP)coupling model based on a multitime scale BESS model,incorporating the electrical and thermal characteristics of Li-ion batteries along with their performance degradation to achieve detailed simulation of grid-connected BESS.Additionally,considering the operating characteristics of energy storage batteries and electrical and thermal abuse factors,we developed a battery pack operational riskmodel,which takes into account SOCand charge-discharge rate(Cr),using amodified failure rate to represent the BESS risk.By integrating detailed simulation of energy storage with predictive failure risk analysis,we obtained a detailed model for BESS risk analysis.This model offers a multi-time scale integrated simulation that spans month-level energy storage simulation times,day-level performance degradation,minutescale failure rate,and second-level BESS characteristics.It offers a critical tool for the study of BESS.Finally,the performance and risk of energy storage batteries under three scenarios—microgrid energy storage,wind power smoothing,and power grid failure response—are simulated,achieving a real-time state-dependent operational risk analysis of the BESS. 展开更多
关键词 Grid-connected battery energy storage system thermal-electric-performance coupling model operational risk model failure rate risk analysis
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Perspectives on risk analysis and control for real-time operation of flood control systems 被引量:1
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作者 Juan Chen Lu Zhang +1 位作者 Guo-zhi Li Ping-an Zhong 《Water Science and Engineering》 CSCD 2024年第4期319-322,共4页
Flood control operation,a non-engineering measure,can efficiently manage flood disasters within a river basin.However,numerous uncertainties exit in the real-time operation of flood control systems,creating risks in d... Flood control operation,a non-engineering measure,can efficiently manage flood disasters within a river basin.However,numerous uncertainties exit in the real-time operation of flood control systems,creating risks in decision-making.As an efficient tool to mitigate these risks,risk management has garnered increasing attention in real-time flood control operation.This communication offers a series of suggestions for future research concerning risk management in real-time flood control operation,including risk assessment,risk diagnosis,and risk control methods. 展开更多
关键词 Flood control system Real-time operation Risk management Risk analysis Risk control
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Editorial:special issue on analysis and control of complex systems in honor of the 90th birthday of Professor Huashu Qin
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作者 Yiguang Hong Shengwei Mei Ping Yang 《Control Theory and Technology》 EI CSCD 2024年第3期343-344,共2页
It is our great pleasure to organize this special issue in Control Theory and Technology in honor of the 90th birthday of Professor Huashu Qin.She is one of the pioneers in control theory and applications in China,and... It is our great pleasure to organize this special issue in Control Theory and Technology in honor of the 90th birthday of Professor Huashu Qin.She is one of the pioneers in control theory and applications in China,and has made many truly outstanding contributions to the field including nonlinear dynamics and control,intelligent control,robotics and complex systems.It is no surprise that she was selected as a representative introduced significantly in“Women in Control”of IEEE Control Systems Magazine. 展开更多
关键词 CONTROL HONOR analysis
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