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GPS and Google Earth based 3D assisted driving system for trucks in surface mines 被引量:9
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作者 SUN Enji NIETO Antonio LI Zhongxue 《Mining Science and Technology》 EI CAS 2010年第1期138-142,共5页
In order to reduce the number of surface mining accidents related to low visibility conditions and blind spots of trucks and to provide 3D information for truck drivers and real time monitored truck information for th... In order to reduce the number of surface mining accidents related to low visibility conditions and blind spots of trucks and to provide 3D information for truck drivers and real time monitored truck information for the remote dispatcher, a 3D assisted driving system (3D-ADS) based on the GPS, mesh-wireless networks and the Google-Earth engine as the graphic interface and mine-mapping server, was developed at Virginia Tech. The research results indicate that this 3D-ADS system has the potential to increase reliability and reduce uncertainty in open pit mining operations by customizing the local 3D digital mining map, con-structing 3D truck models, tracking vehicles in real time using a 3D interface and indicating available escape routes for driver safety. 展开更多
关键词 surface mining safety 3D assisted driving system Google Earth API GPS
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Zigbee/Google Earth based assisted driving system in mining 被引量:3
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作者 SUN En-ji NIETO Antonio 《Mining Science and Technology》 EI CAS 2009年第5期626-630,共5页
The Assisted Driving System (ADS) for haul trucks operating in surface mining and construction sites is to reduce accidents related to low visibility conditions. This system is based on the GPS, Zigbee, and the Google... The Assisted Driving System (ADS) for haul trucks operating in surface mining and construction sites is to reduce accidents related to low visibility conditions. This system is based on the GPS, Zigbee, and the Google-Earth engine as the graphic interface and mine-mapping server. The system has the capability to pin-point and track vehicles in real time using a 3D interface, which is based on user-based AutoCAD mine maps using the Google-Earth graphics interface. All equipped vehicles are shown in a 3D mine map stored in a local server through a wireless network. When low visibility conditions are present, the system indicates available exit/escape routes for driver safety. The ADS potentially increases reliability and reduces uncertainty in open pit mining operations. 展开更多
关键词 3D simulation GPS MINING assisted driving system Google Earth
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Simulation on Driving System Used for Differential Steering of Electric Scooter 被引量:2
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作者 舒红宇 许永亮 +1 位作者 陈齐平 任凯 《Transactions of Tianjin University》 EI CAS 2011年第2期103-106,共4页
To investigate the feasibility and effectiveness of the designed control system used for driving and steering of an electric scooter, a model of differential steering was developed. The function of electronic differen... To investigate the feasibility and effectiveness of the designed control system used for driving and steering of an electric scooter, a model of differential steering was developed. The function of electronic differential steering was realized by controlling the speed of right or left wheel and the corresponding speed difference. The control system was simulated with MATLAB/SIMUL1NK and ADAMS. It is found that the motor load torque is proportional to the tire vertical force, so the adhesive capacity is met. The electric scooter can operate stably on the slope road at a speed of more than 1.5 m/s and turn stably at yawing velocities of 10° and 90°per second. 展开更多
关键词 electric scooter driving system differential steering proportion-integration-differentiation
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The dynamic running law study on driving system of hydraulic winder 被引量:1
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作者 彭佑多 刘德顺 +2 位作者 郭迎福 张永忠 文西芹 《Journal of Coal Science & Engineering(China)》 2002年第1期73-78,共6页
Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist... Dynamic running law of the hydraulic driving system decides the hoisting cage velocity curve in a hoisting cycle and is decided by the characteristic of the hydraulic driving system and by the operating speed of hoist driver. The paper studies the dynamic running law of hydraulic driving system, analyses the influence of driver operating speed on the dynamic running characteristic, and points out the reasonable driver operating speed to control the dynamic stress in rope and to reduce the oscillation of rope system. 展开更多
关键词 hydraulic winder driving system hoisting cage dynamic running characteristic driver operating speed
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Development of belt conveyor driving system 被引量:1
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作者 付峻青 王聪 霍伟 《Journal of Coal Science & Engineering(China)》 2004年第1期83-87,共5页
A short review for the existing various driving methods for belt conveyor was given, which include the analysis and comparison about the advantages, disadvantages and suitable application range of these methods. Based... A short review for the existing various driving methods for belt conveyor was given, which include the analysis and comparison about the advantages, disadvantages and suitable application range of these methods. Based on this the vari-able-frequency-control(VFC) method for belt conveyor drive was fully discussed with focus on its application in medium-high voltage range. The principle of Neutral Point Clamped (NPC) Three-Level Inverter using high-voltage IGBTs together with the control strategy of rotor field-oriented vector control for induction motor drive were illustrated. 展开更多
关键词 belt conveyor driving system variable-frequency-control three-level inverter
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A Sine Driving System for the Dynamic Experiment of the Aerofoil Model
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作者 XIE Yajun, GUO Qi, ZHANG Li, XI Zhongxiang Northwestern Polytechnical University, Xi’an, 710072, P. R. China 《International Journal of Plant Engineering and Management》 2000年第4期149-153,共5页
The design principle and the structural characters of a new sine driving system apparatus, which have been used by NPU NF-3 wind tunnel in the dynamic stall experiments on the oscillating aerofoil model from 1994, is ... The design principle and the structural characters of a new sine driving system apparatus, which have been used by NPU NF-3 wind tunnel in the dynamic stall experiments on the oscillating aerofoil model from 1994, is introduced. Some measures to improve the stability and flexibility are studied. The obvious advantages of the system are its simple structure, convenient operation and more accurate sine relationship between the attack angle and the rotating angle of the aerofoil The driving system has been proved advisable comparing with the experimental results both abroad and in many dynamic tests in NF-3 wind tunnel. It can provide guidelines for the study of the aerodynamic properties on the oscillating aerofoil. 展开更多
关键词 aerofoil dynamic experiment sine driving system
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Analysis and Control over Noises in Main Driving System of XK-736-type NC Miller
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作者 Yan Jun 《International Journal of Plant Engineering and Management》 2012年第2期117-124,共8页
Some concrete methods are suggested in the article to control noises in main driving system of XK-736-type NC miller by analyzing working conditions of gears in the main driving system and bearings in the spindle gear... Some concrete methods are suggested in the article to control noises in main driving system of XK-736-type NC miller by analyzing working conditions of gears in the main driving system and bearings in the spindle gearshift system. Without changing the original design, noises are reduced ideally by modifying gear top, and by controlling the profile error ; the central distance of meshing gear, the quality of the inner and outer rings of bearings ; and the fit accuracy among bearing, hole and axis. The results may provide a reference for diagnosing and maintaining in future use. 展开更多
关键词 NC miller main driving system NOISES
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Implementation and Evaluation of Local Dynamic Map in Safety Driving Systems 被引量:13
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作者 Hideki Shimada Akihiro Yamaguchi +1 位作者 Hiroaki Takada Kenya Sato 《Journal of Transportation Technologies》 2015年第2期102-112,共11页
Cooperative safety driving systems using vehicle-to-vehicle and vehicle-to infrastructure communication are developed. Sensor data of vehicles and infrastructures are communicated in the cooperative safety driving sys... Cooperative safety driving systems using vehicle-to-vehicle and vehicle-to infrastructure communication are developed. Sensor data of vehicles and infrastructures are communicated in the cooperative safety driving system. LDM (Local Dynamic Map) is standardized by ETSI (European Telecommunications Standards Institute) to manage the vehicle sensor data and the map data. Implementations of LDM are reported on documents of ETSI, but there are no numerical results. The implementations of LDM are deployed the database management system. We think that the response time of the database becomes higher as the number of vehicles grows. In this paper, we have implemented and evaluated the LDM with the collision detection application. 展开更多
关键词 LOCAL Dynamic MAP ITS COOPERATIVE SAFETY driving systemS
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On the Development of an Effective Pressure Driving System for Ultra-Low Permeability Reservoirs 被引量:4
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作者 Yapu Zhang Zhengming Yang +2 位作者 Dajian Li Xuewei Liu Xinli Zhao 《Fluid Dynamics & Materials Processing》 EI 2021年第6期1067-1075,共9页
Given its relevance to the exploitation of ultra-low permeability reservoirs,which account for a substantial proportion of the world’s exploited and still unexploited reserves,in the present study the development of ... Given its relevance to the exploitation of ultra-low permeability reservoirs,which account for a substantial proportion of the world’s exploited and still unexploited reserves,in the present study the development of an adequate water injection system is considered.Due to the poor properties and weak seepage capacity of these reservoirs,the water injection pressure typically increases continuously during water flooding.In this research,the impact on such a process of factors as permeability,row spacing,and pressure gradient is evaluated experimentally using a high-pressure large-scale outcrop model.On this basis,a comprehensive evaluation coefficient is introduced able to account for the effective driving pressure. 展开更多
关键词 Ultra-low permeability reservoir physical simulation effective development water flooding effective driving coefficient
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Optimum Driving System Design for Dual-Motor Pure Electric Vehicles 被引量:1
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作者 Hongwei Zhang Weichi Chen +4 位作者 Zhuangzhuang Shang Zhifeng Xu Zepeng Gao Yong Chen Hongbin Ren 《Journal of Beijing Institute of Technology》 EI CAS 2020年第4期592-602,共11页
A pure electric vehicle driven by dual motors is taken as the research object and the driving scheme of the driving motor is improved to increase the transmission efficiency of existing electric vehicles.Based on the ... A pure electric vehicle driven by dual motors is taken as the research object and the driving scheme of the driving motor is improved to increase the transmission efficiency of existing electric vehicles.Based on the architecture of the transmission system,we propose vehicle performance parameters and performance indexes of a pure electric vehicle,a time-sharing driving strategy of dual motors.First,the parameters of the battery,motor,and transmission system are matched.Then,the electric vehicle transmission model is built in Amesim and the control strategy is designed in Simulink.With the optimization goal of improving the vehicle’s dynamic performance and driving range,the optimal parameters are determined through analysis.Finally,the characteristics of the motor are tested on the bench.The results show that the energy-saving potential of the timesharing driven double motor is higher,and the driving mileage of the double motor drive is increased by 4%. 展开更多
关键词 pure electric vehicle vehicle powertrain parameter matching time sharing drive
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Potential Driving Systems Associated with Extreme Rainfall across East Africa during October to December (OND) Season 2019
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作者 Constantine Ingeri Wang Wen +5 位作者 Joseph Ndakize Sebaziga Vedaste Iyakaremye Samuel Ekwacu Prosper Ayabagabo Anthony Twahirwa Jonah Kazora 《Journal of Geoscience and Environment Protection》 2024年第7期25-49,共25页
The East African (EA) region highly experiences intra-seasonal and inter-annual variation in rainfall amounts. This study investigates the driving factors for anomalous rainfall events observed during the season of Oc... The East African (EA) region highly experiences intra-seasonal and inter-annual variation in rainfall amounts. This study investigates the driving factors for anomalous rainfall events observed during the season of October-November-December (OND) 2019 over the region. The study utilized daily rainfall data from Climate Hazards Group InfraRed Precipitation with Station Data Version 2 (CHIRPSv2) and the driving systems data. Statistical spatiotemporal analysis, correlation, and composite techniques were performed to investigate the teleconnection between OND 2019 seasonal rainfall and global synoptic climate systems. The findings showed that the OND 2019 experienced seasonal rainfall that was twice or greater than its seasonal climatology and varied with location. Further, the OND 2019 rainfall showed a positive correlation with the Indian Ocean Dipole (IOD) (0.81), Nino 3 (0.51), Nino 3.4 (0.47), Nino 4 (0.40), Pacific Decadal Oscillation (PDO) (0.22), and North Tropical Atlantic (NTA) (0.02), while El Nino-Southern Oscillation (ENSO) showed a negative correlation (−0.30). The region was dominated by southeasterly warming and humid winds that originated from the Indian Ocean, while the geopotential height, vertical velocity, and vorticity anomalies were closely related to the anomalous rainfall characteristics. The study deduced that the IOD was the major synoptic system that influenced maximum rainfall during the peak season of OND 2019. This study therefore provided insights on the diagnosis study of OND 2019 anomalous rainfall and its attribution over the EA. The findings of the study will contribute to improvements in forecasting seasonal rainfall by regional climate centers and national meteorological centers within the region. 展开更多
关键词 East Africa driving Climate systems October-November-December (OND) 2019 Rainfall
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On Designing of the Main Elements of a Hybrid-Electric Vehicle Driving System
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作者 Petre-Marian Nicolae Ileana-Diana Nicolae Ionut-Daniel Smarandescu 《Journal of Power and Energy Engineering》 2014年第4期103-112,共10页
The paper deals with the designing of an electric drive system used for hybrid electric vehicles. The driving system is realized with an induction motor and a voltage source inverter. Specifically, the application is ... The paper deals with the designing of an electric drive system used for hybrid electric vehicles. The driving system is realized with an induction motor and a voltage source inverter. Specifically, the application is for a series hybrid vehicle powered by electric storage batteries charged by solar batteries. In the first part of the paper the designing of the electric storage batteries and of the photoelectric system is presented. In the second part of the paper some aspects regarding the designing of the induction motor are presented. Then some aspects concerning the voltage source inverter designing are exposed. 展开更多
关键词 Hybrid Electric Vehicle Drive system DESIGNING Electric Storage Batteries Photoelectric system Induction Motor Voltage Source Inverter
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Multimodal large-language model empowering nextgeneration autonomous driving systems
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作者 Zhiqiang Hu Mingxing Xu Qixiu Cheng 《Journal of Intelligent and Connected Vehicles》 2025年第2期1-3,共3页
1 Introduction Autonomous driving technology has made significant advancements in recent years.The evolution of autonomous driving systems from traditional modular designs to end-to-end learning paradigms has led to c... 1 Introduction Autonomous driving technology has made significant advancements in recent years.The evolution of autonomous driving systems from traditional modular designs to end-to-end learning paradigms has led to comprehensive improvements in driving capabilities.In modular designs,driving tasks are segmented into independent modules,such as perception,decision-making,planning,and control. 展开更多
关键词 driving capabilities autonomous driving systems end end learning next generation MULTIMODAL large language model autonomous driving traditional modular designs
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Acomprehensive survey of physical adversarial vulnerabilities in autonomous driving systems
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作者 Shuai ZHAO Boyuan ZHANG +3 位作者 Yucheng SHI Yang ZHAI Yahong HAN Qinghua HU 《Frontiers of Information Technology & Electronic Engineering》 2025年第4期510-533,共24页
Autonomous driving systems(ADSs)have attracted wide attention in the machine learning communities.With the help of deep neural networks(DNNs),ADSs have shown both satisfactory performance under significant uncertainti... Autonomous driving systems(ADSs)have attracted wide attention in the machine learning communities.With the help of deep neural networks(DNNs),ADSs have shown both satisfactory performance under significant uncertainties in the environment and the ability to compensate for system failures without external intervention.However,the vulnerability of ADSs has raised concerns since DNNs have been proven vulnerable to adversarial attacks.In this paper,we present a comprehensive survey of current physical adversarial vulnerabilities in ADSs.We first divide the physical adversarial attack methods and defense methods by their restrictions of deployment into three scenarios:the real-world,simulator-based,and digital-world scenarios.Then,we consider the adversarial vulnerabilities that focus on various sensors in ADSs and separate them as camera-based,light detection and ranging(LiDAR)based,and multifusion-based attacks.Subsequently,we divide the attack tasks by traffic elements.For the physical defenses,we establish the taxonomy with reference to input image preprocessing,adversarial example detection,and model enhancement for the DNN models to achieve full coverage of the adversarial defenses.Based on the above survey,we finally discuss the challenges in this research field and provide further outlook on future directions. 展开更多
关键词 Physical adversarial attacks Physical adversarial defenses Artificial intelligence safety Deep learning Autonomous driving system Data-fusion Adversarial vulnerability
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Dynamic changes and driving factors of ecosystem service value(ESV)in the Northeast Forest Belt of China 被引量:1
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作者 Jiao Shi Yujuan Gao Yuyou Zou 《Journal of Forestry Research》 2025年第2期167-186,共20页
The scientific assessment of ecosystem ser-vice value(ESV)plays a critical role in regional ecologi-cal protection and management,rational land use planning,and the establishment of ecological security barriers.The ec... The scientific assessment of ecosystem ser-vice value(ESV)plays a critical role in regional ecologi-cal protection and management,rational land use planning,and the establishment of ecological security barriers.The ecosystem service value of the Northeast Forest Belt from 2005 to 2020 was assessed,focusing on spatial–temporal changes and the driving forces behind these dynamics.Using multi-source data,the equivalent factor method,and geo-graphic detectors,we analyzed natural and socio-economic factors affecting the region.which was crucial for effective ecological conservation and land-use planning.Enhanced the effectiveness of policy formulation and land use plan-ning.The results show that the ESV of the Northeast Forest Belt exhibits an overall increasing trend from 2005 to 2020,with forests and wetlands contributing the most.However,there are significant differences between forest belts.Driven by natural and socio-economic factors,the ESV of forest belts in Heilongjiang and Jilin provinces showed significant growth.In contrast,the ESV of Forest Belts in Liaoning and Inner Mongolia of China remains relatively stable,but the spatial differentiation within these regions is characterized by significant clustering of high-value and low-value areas.Furthermore,climate regulation and hydrological regulation services were identified as the most important ecological functions in the Northeast Forest Belt,contributing greatly to regional ecological stability and human well-being.The ESV in the Northeast Forest Belt is improved during the study period,but the stability of the ecosystem is still chal-lenged by the dual impacts of natural and socio-economic factors.To further optimize regional land use planning and ecological protection policies,it is recommended to prior-itize the conservation of high-ESV areas,enhance ecological restoration efforts for wetlands and forests,and reasonably control the spatial layout of urban expansion and agricul-tural development.Additionally,this study highlights the importance of tailored ecological compensation policies and strategic land-use planning to balance environmental protec-tion and economic growth. 展开更多
关键词 Ecosystem service value(ESV) Northeast Forest Belt of China Equivalent factor method Geographic detectors driving factors
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Research framework for integrated geography:Composite driving-system evolution-coupling mechanism-synergistic regulation
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作者 Wenwu Zhao Zizhao Ni +2 位作者 Caichun Yin Yanxu Liu Paulo Pereira 《Geography and Sustainability》 2025年第3期1-8,共8页
Amid ongoing global environmental change and the critical pursuit of sustainable development,human-environment systems are exhibiting increasingly complex dynamic evolutions and spatial relationships,underscoring an u... Amid ongoing global environmental change and the critical pursuit of sustainable development,human-environment systems are exhibiting increasingly complex dynamic evolutions and spatial relationships,underscoring an urgent need for innovative research frameworks.Integrated geography synthesizes physical geography,human geography,and geographic information science,providing key frameworks for understanding complex human-environment systems.This editorial proposes an emerging research framework for integrated geography—“Composite driving-System evolution-Coupling mechanism-Synergistic regulation(CSCS)”—based on key issues such as climate change,biodiversity loss,resource scarcity,and social-ecological interactions,which have been highlighted in both recent critical literature on human-environment systems and UN assessment reports.The framework starts with diverse composite driving forces,extends to the evolution of human-environment system structures,processes,and functions that these drivers induce,explores couplings within human-environment systems,and calls for regulation aimed at sustainable development in synergies.Major research frontiers include understanding the cascading“evolution-coupling”effects of shocks;measuring system resilience,thresholds,and safe and just operating space boundaries;clarifying linkage mechanisms across scales;and achieving synergistic outcomes for multi-objective sustainability.This framework will help promote the interdisciplinary integration and development of integrated geography,and provide geographical solutions for the global sustainable development agenda. 展开更多
关键词 Integrated geography driving Evolution COUPLING REGULATION Human-environment system
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Driving pressure in acute respiratory distress syndrome for developing a protective lung strategy:A systematic review
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作者 Hassan A Alzahrani Nadia Corcione +9 位作者 Saeed M Alghamdi Abdulghani O Alhindi Ola A Albishi Murad M Mawlawi Wheb O Nofal Samah M Ali Saad A Albadrani Meshari A AlJuaid Abdullah M Alshehri Mutlaq Z Alzluaq 《World Journal of Critical Care Medicine》 2025年第2期158-169,共12页
BACKGROUND Acute respiratory distress syndrome(ARDS)is a critical condition characterized by acute hypoxemia,non-cardiogenic pulmonary edema,and decreased lung compliance.The Berlin definition,updated in 2012,classifi... BACKGROUND Acute respiratory distress syndrome(ARDS)is a critical condition characterized by acute hypoxemia,non-cardiogenic pulmonary edema,and decreased lung compliance.The Berlin definition,updated in 2012,classifies ARDS severity based on the partial pressure of arterial oxygen/fractional inspired oxygen fraction ratio.Despite various treatment strategies,ARDS remains a significant public health concern with high mortality rates.AIM To evaluate the implications of driving pressure(DP)in ARDS management and its potential as a protective lung strategy.METHODS We conducted a systematic review using databases including EbscoHost,MEDLINE,CINAHL,PubMed,and Google Scholar.The search was limited to articles published between January 2015 and September 2024.Twenty-three peer-reviewed articles were selected based on inclusion criteria focusing on adult ARDS patients undergoing mechanical ventilation and DP strategies.The literature review was conducted and reported according to PRISMA 2020 guidelines.RESULTS DP,the difference between plateau pressure and positive end-expiratory pressure,is crucial in ARDS management.Studies indicate that lower DP levels are significantly associated with improved survival rates in ARDS patients.DP is a better predictor of mortality than tidal volume or positive end-expiratory pressure alone.Adjusting DP by optimizing lung compliance and minimizing overdistension and collapse can reduce ventilator-induced lung injury.CONCLUSION DP is a valuable parameter in ARDS management,offering a more precise measure of lung stress and strain than traditional metrics.Implementing DP as a threshold for safety can enhance protective ventilation strategies,po-tentially reducing mortality in ARDS patients.Further research is needed to refine DP measurement techniques and validate its clinical application in diverse patient populations. 展开更多
关键词 Acute respiratory distress syndrome Mechanical ventilation driving pressure Respiratory care Intensive care unit Pulmonary disease
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A Collaborative Protection Mechanism for System-on-Chip Functional Safety and Information Security in Autonomous Driving
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作者 Zhongyi Xu Lei Xin +1 位作者 Zhongbai Huang Deguang Wei 《Journal of Electronic Research and Application》 2025年第2期226-232,共7页
This article takes the current autonomous driving technology as the research background and studies the collaborative protection mechanism between its system-on-chip(SoC)functional safety and information security.It i... This article takes the current autonomous driving technology as the research background and studies the collaborative protection mechanism between its system-on-chip(SoC)functional safety and information security.It includes an introduction to the functions and information security of autonomous driving SoCs,as well as the main design strategies for the collaborative prevention and control mechanism of SoC functional safety and information security in autonomous driving.The research shows that in the field of autonomous driving,there is a close connection between the functional safety of SoCs and their information security.In the design of the safety collaborative protection mechanism,the overall collaborative protection architecture,SoC functional safety protection mechanism,information security protection mechanism,the workflow of the collaborative protection mechanism,and its strategies are all key design elements.It is hoped that this analysis can provide some references for the collaborative protection of SoC functional safety and information security in the field of autonomous driving,so as to improve the safety of autonomous driving technology and meet its practical application requirements. 展开更多
关键词 Autonomous driving SoC functional safety Information security Collaborative protection mechanism Collaborative protection architecture
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Response of Ecosystem Service Value Based on Land Use Changes and Analysis of its Driving Factors in Typical Hilly Region with Red Soil 被引量:6
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作者 邹金浪 王金政 +1 位作者 王鹏 乐文年 《Agricultural Science & Technology》 CAS 2010年第11期150-154,共5页
The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation w... The contribution rate of ecosystem service value variation was used to analyze the effects of land use changes on the changes of ecosystem service value in Xingguo County during 1996-2005.Grey integrated correlation was employed to explore the contribution level of the indicators such as total population,urbanization level,proportion of primary industry and investment of social fixed assets on ecosystem service value,and the correlation analysis was also carried out.The results showed that the ecosystem service value in Xingguo County during 1996-2005 mainly was woodland,and the decrease of woodland area was the major reason for the sustained reduction of ecosystem service value.With the further increase of market demand and the incentives of local government,the garden area rapidly increased during 2001-2005,and the influence degree of garden towards the changes of ecosystem service value was only second to woodland,ranking No.2.Four socio-economic indicators had different correlation degree with ecosystem service value during the different research periods.Total population,urbanization level and proportion of primary industry had high correlation degree with ecosystem service value,whereas the influence degree of various socio-economic indicators on ecosystem service value was equal with each other day by day.Urbanization level,investment of social fixed assets and total population had significant negative correlation with ecosystem service value,while the proportion of primary industry had positive correlation with ecosystem service value. 展开更多
关键词 Ecosystem service value Land use change Gray correlation analysis driving factor Hilly region with red soil
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Theoretical analysis of output speed of multi-pump and multi-motor driving system 被引量:44
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作者 WEN DeSheng 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第4期992-997,共6页
A theory for multi-pump and multi-motor hydraulic systems is presented in this paper based on the analysis of the advantages and disadvantages of the popular hydraulic transmission and the double-stator motor(pump).By... A theory for multi-pump and multi-motor hydraulic systems is presented in this paper based on the analysis of the advantages and disadvantages of the popular hydraulic transmission and the double-stator motor(pump).By taking the single-acting fixed displacement multi-pump and multi-motor driving system as an example,the output speeds in a variety of connections of this novel hydraulic transmission are analyzed theoretically.This research work lays a theoretical foundation for the study of the multi-pump and multi-motor driving system and for the design of the system principle diagram. 展开更多
关键词 multi-pump and multi-motor driving system way of connection TORQUE turning speed differential motor
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