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A Study on Diagnostic Assist Systems of Chronic Obstructive Pulmonary Disease from Medical Images by Deep Learning
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作者 Toru Kimura Takashi Kawakami +3 位作者 Akihiro Kikuchi Ryosuke Ooev Masaki Akiyama Hiroyuki Horikoshi 《Journal of Computer and Communications》 2018年第1期21-31,共11页
In this paper, we propose new diagnostic assist systems of medical images using deep learning algorithms. Specifically, we aim to develop a diagnostic support system for the very early stage of chronic obstructive pul... In this paper, we propose new diagnostic assist systems of medical images using deep learning algorithms. Specifically, we aim to develop a diagnostic support system for the very early stage of chronic obstructive pulmonary disease (COPD) based on the CT images. It is said that COPD is a disease that develops due to long-term smoking, and it is said that there are a large number of latent onset reserve forces. By discovering this COPD in the very early period 0 and improving the living conditions, subsequent severity can be avoided in many cases, so a system that will help diagnosis by professional radiologists is needed. We show the some experimental results examined by the constructed system. 展开更多
关键词 Deep Learning CT Images DIAGNOSTIC assist systemS CHRONIC OBSTRUCTIVE PULMONARY Disease
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Anesthesia management of a patient undergoing implantation of a left ventricular assist system:A case report
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作者 Shu-Guang Wu Wei He 《World Journal of Anesthesiology》 2022年第1期1-7,共7页
BACKGROUND Heart failure is generally regarded as a progressive and irreversible medical condition.The EVAHEART is an implantable left ventricular assist system.CASE SUMMARY We report the anesthesia management of a 56... BACKGROUND Heart failure is generally regarded as a progressive and irreversible medical condition.The EVAHEART is an implantable left ventricular assist system.CASE SUMMARY We report the anesthesia management of a 56-year-old male patient with dilated cardiomyopathy undergoing an EVAHEART implantation.Transesophageal echocardiography is crucial to ensure the correct positioning of the device and the proper aortic valve outflow.Because the continuous blood flow device functions best under low systemic and pulmonary vascular resistance,milrinone is the preferred drug.Our patient was accompanied by pulmonary hypertension,so during the operation,nitric oxide was used to reduce pulmonary artery pressure.CONCLUSION The cardiac output achieved by the patient with the assistance of EVAHEART can reach 4 L/min,which of course depends on the front load,rear load,and pump speed. 展开更多
关键词 Heart failure ANESTHESIA HEMODYNAMICS Left ventricular assist device Transesophageal echocardiography Pulmonary hypertension
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Assistive Robotics for Upper Limb Physical Rehabilitation:A Systematic Review and Future Prospects
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作者 Andrés Guatibonza Leonardo Solaque +1 位作者 Alexandra Velasco Lina Peñuela 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期50-73,共24页
Physical assistive robotics are oriented to support and improve functional capacities of people.In physical rehabilitation,robots are indeed useful for functional recovery of affected limb.However,there are still open... Physical assistive robotics are oriented to support and improve functional capacities of people.In physical rehabilitation,robots are indeed useful for functional recovery of affected limb.However,there are still open questions related to technological aspects.This work presents a systematic review of upper limb rehabilitation robotics in order to analyze and establish technological challenges and future directions in this area.A bibliometric analysis was performed for the systematic literature review.Literature from the last six years,conducted between August 2020 and May 2021,was reviewed.The methodology for the literature search and a bibliometric analysis of the metadata are presented.After a preliminary search resulted in 820 articles,a total of 66 articles were included.A concurrency network and bibliographic analysis were provided.And an analysis of occurrences,taxonomy,and rehabilitation robotics reported in the literature is presented.This review aims to provide to the scientific community an overview of the state of the art in assistive robotics for upper limb physical rehabilitation.The literature analysis allows access to a gap of unexplored options to define the technological prospects applied to upper limb physical rehabilitation robotics. 展开更多
关键词 Upper limb REHABILITATION assistive robotics Human-machine interaction Robotic systems Virtual reality Rehabilitation monitoring
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Advances in magnetic-assisted triboelectric nanogenerators:structures,materials and self-sensing systems
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作者 Pengfan Wu Chenxi Zhao +5 位作者 Endian Cui Shiwei Xu Tao Liu Fayang Wang Chengkuo Lee Xiaojing Mu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第5期162-188,共27页
Triboelectric nanogenerators(TENG),renowned for their remarkable capability to harness weak mechanical energy from the environment,have gained considerable attention owing to their cost-effectiveness,high output,and a... Triboelectric nanogenerators(TENG),renowned for their remarkable capability to harness weak mechanical energy from the environment,have gained considerable attention owing to their cost-effectiveness,high output,and adaptability.This review provides a unique perspective by conducting a comprehensive and in-depth analysis of magnetically assisted TENGs that encompass structures,materials,and self-powered sensing systems.We systematically summarize the diverse functions of the magnetic assistance for TENGs,including system stiffness,components of the hybrid electromagnetic-triboelectric generator,transmission,and interaction forces.In the material domain,we review the incorporation of magnetic nano-composites materials,along with ferrofluid-based TENG and microstructure verification,which have also been summarized based on existing research.Furthermore,we delve into the research progress on physical quantity sensing and human-machine interface in magnetic-assisted TENGs.Our analysis highlights that magnetic assistance extends beyond the repulsive and suction forces under a magnetic field,thereby playing multifaceted roles in improving the output performance and environmental adaptability of the TENGs.Finally,we present the prevailing challenges and offer insights into the future trajectory of the magnetic-assisted TENGs development. 展开更多
关键词 triboelectric nanogenerator magnetic assistance tuning structure controlled material preparation self-powered system
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Sub-6GHz Assisted mmWave Hybrid Beamforming with Self-Supervised Learning
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作者 Li Hongyao Gao Feifei +3 位作者 Lin Bo Wu Huihui Gu Yuantao Xi Jianxiang 《China Communications》 2025年第1期158-170,共13页
In this paper,we propose a sub-6GHz channel assisted hybrid beamforming(HBF)for mmWave system under both line-of-sight(LOS)and non-line-of-sight(NLOS)scenarios without mmWave channel estimation.Meanwhile,we resort to ... In this paper,we propose a sub-6GHz channel assisted hybrid beamforming(HBF)for mmWave system under both line-of-sight(LOS)and non-line-of-sight(NLOS)scenarios without mmWave channel estimation.Meanwhile,we resort to the selfsupervised approach to eliminate the need for labels,thus avoiding the accompanied high cost of data collection and annotation.We first construct the dense connection network(DCnet)with three modules:the feature extraction module for extracting channel characteristic from a large amount of channel data,the feature fusion module for combining multidimensional features,and the prediction module for generating the HBF matrices.Next,we establish a lightweight network architecture,named as LDnet,to reduce the number of model parameters and computational complexity.The proposed sub-6GHz assisted approach eliminates mmWave pilot resources compared to the method using mmWave channel information directly.The simulation results indicate that the proposed DCnet and LDnet can achieve the spectral efficiency that is superior to the traditional orthogonal matching pursuit(OMP)algorithm by 13.66% and 10.44% under LOS scenarios and by 32.35% and 27.75% under NLOS scenarios,respectively.Moreover,the LDnet achieves 98.52% reduction in the number of model parameters and 22.93% reduction in computational complexity compared to DCnet. 展开更多
关键词 hybrid beamforming mmWave selfsupervised learning sub-6GHz assisted mmWave transmission sub-6GHz channel
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基于NodeMCU和Home Assistant的智能家居控制系统
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作者 杨骏 梁念渝 王凯 《通讯世界》 2024年第8期124-126,共3页
为了提高家居生活的舒适性和便利性,开发了一套智能家居控制系统。该系统采用节点微控制单元(NodeMCU)作为基础硬件,负责收集传感器数据并操控相关执行器件。同时,该系统利用消息队列遥测传输协议(MQTT)和WiˉFi技术构建数据传输链路。... 为了提高家居生活的舒适性和便利性,开发了一套智能家居控制系统。该系统采用节点微控制单元(NodeMCU)作为基础硬件,负责收集传感器数据并操控相关执行器件。同时,该系统利用消息队列遥测传输协议(MQTT)和WiˉFi技术构建数据传输链路。此外,该系统利用开源的Home Assistant系统建立了后台服务端,以实现数据的图形化展示。用户可通过安卓移动设备实时监控家居环境状况,并对智能设备实施控制。该系统经过严格测试,表现稳定,显著提高了家居环境的智能化程度。 展开更多
关键词 NodeMCU Home assistant 智能家居
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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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An RGB-D Camera Based Visual Positioning System for Assistive Navigation by a Robotic Navigation Aid 被引量:6
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作者 He Zhang Lingqiu Jin Cang Ye 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第8期1389-1400,共12页
There are about 253 million people with visual impairment worldwide.Many of them use a white cane and/or a guide dog as the mobility tool for daily travel.Despite decades of efforts,electronic navigation aid that can ... There are about 253 million people with visual impairment worldwide.Many of them use a white cane and/or a guide dog as the mobility tool for daily travel.Despite decades of efforts,electronic navigation aid that can replace white cane is still research in progress.In this paper,we propose an RGB-D camera based visual positioning system(VPS)for real-time localization of a robotic navigation aid(RNA)in an architectural floor plan for assistive navigation.The core of the system is the combination of a new 6-DOF depth-enhanced visual-inertial odometry(DVIO)method and a particle filter localization(PFL)method.DVIO estimates RNA’s pose by using the data from an RGB-D camera and an inertial measurement unit(IMU).It extracts the floor plane from the camera’s depth data and tightly couples the floor plane,the visual features(with and without depth data),and the IMU’s inertial data in a graph optimization framework to estimate the device’s 6-DOF pose.Due to the use of the floor plane and depth data from the RGB-D camera,DVIO has a better pose estimation accuracy than the conventional VIO method.To reduce the accumulated pose error of DVIO for navigation in a large indoor space,we developed the PFL method to locate RNA in the floor plan.PFL leverages geometric information of the architectural CAD drawing of an indoor space to further reduce the error of the DVIO-estimated pose.Based on VPS,an assistive navigation system is developed for the RNA prototype to assist a visually impaired person in navigating a large indoor space.Experimental results demonstrate that:1)DVIO method achieves better pose estimation accuracy than the state-of-the-art VIO method and performs real-time pose estimation(18 Hz pose update rate)on a UP Board computer;2)PFL reduces the DVIO-accrued pose error by 82.5%on average and allows for accurate wayfinding(endpoint position error≤45 cm)in large indoor spaces. 展开更多
关键词 assistive navigation pose estimation robotic navigation aid(RNA) simultaneous localization and mapping visual-inertial odometry visual positioning system(VPS)
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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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Assisted Hatching in Couples with Advanced Maternal Age: A Systematic Review and Meta-analysis 被引量:2
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作者 Fan HE Chan-yu ZHANG +2 位作者 Li-si WANG Sang-lin LI Li-na HU 《Current Medical Science》 SCIE CAS 2018年第3期552-557,共6页
This systematic review aimed to evaluate the efficacy and safety of assisted hatching (AH) performed in couples with advanced maternal age. We searched for randomized controlled trials (RCTs) in electronic databas... This systematic review aimed to evaluate the efficacy and safety of assisted hatching (AH) performed in couples with advanced maternal age. We searched for randomized controlled trials (RCTs) in electronic databases, including MEDLINE, EMBASE and CENTRAL (from inception to January 2018); in addition, we hand-searched the reference lists of included studies and similar reviews. We included RCTs comparing AH versus no treatment (control). The meta-analysis was performed by RevMan 5.3 software. The search retrieved 943 records and 8 RCTs were included, comprising 870 cycles (n=440 for AH, and n=430 for control). There was no significant difference in the rates of live birth (RR 0.88, 95% CI 0.65 to 1.18, 3 RCTs, n-427,I^2=0%), clinical pregnancy (RR 1.00, 95% CI 0.83 to 1.19, 8 RCTs, n=870, I^2=22%), implantation (RR 1.07, 95% CI 0.83 to 1.39, 4 RCTs, n=1359, I^2=0%), miscarriage (RR 1.13, 95% CI 0.66 to 1.94, 2 RCTs, n=116, I^2=0%) and multiple pregnancy (RR 0.89, 95% CI 0.31 to 2.52, 1 RCT, n=97,I^2=not applicable) between the treatment group and control group. No reasonable conclusions could be drawn regarding reproductive outcomes after AH in patients with advanced maternal age due to the small sample pooled in meta-analyses. Studies of high methodological quality and with adequate power are necessary to further investigate the value of AH in assisted conception of those patients. 展开更多
关键词 assisted hatching advanced maternal age in vitro fertilization frozen-thawed embryo transfer
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Research on Stealth Assistant Decision System of Submarine Voyage Stage 被引量:2
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作者 Yushan Sun Wenlong Jiao +2 位作者 Guocheng Zhang Lifeng Wang Junhan Cheng 《Journal of Marine Science and Application》 CSCD 2020年第2期208-217,共10页
Stealth security has always been considered as an important guarantee for the vitality and combat effectiveness of submarines.In accordance with the stealth requirements of submarines performing stealth voyage tasks,t... Stealth security has always been considered as an important guarantee for the vitality and combat effectiveness of submarines.In accordance with the stealth requirements of submarines performing stealth voyage tasks,this paper proposes a stealth assistant decision system.Firstly,the submarine stealth posture is acquired.A fuzzy neural network inference engine based on improved simplified particle swarm optimization is designed.The auxiliary decision-making scheme for state control and maneuver avoidance of submarine and its equipment is automatically generated.Secondly,the simulation and deduction of the assistant decision-making scheme are realized by the calculation modules of sound source level,propagation loss,and stealth situation.The assistant decision-making scheme and simulation result provide decision support for the commander.Thirdly,the simulation experiment platform of the submarine stealth assistant decision system is constructed.The submarine stealth assistant decision system described in this paper can quickly and efficiently produce assistant decision-making schemes,including submarine and equipment control and maneuver avoidance.The scheme is in line with the combat experience and the results of the pre-model simulation experiments,whereas the simulation deduction evaluates the rationality and effectiveness of the selected scheme.The submarine stealth assistant decision system can adapt to a complex battlefield environment in addition to rapidly and accurately providing assistance in decision-making. 展开更多
关键词 SUBMARINE Dynamic stealth assistant decision Fuzzy neural network Improved simplified particle swarm optimization
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Design and Implementation of a System for Laser Assisted Milling of Advanced Materials 被引量:2
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作者 WU Xuefeng FENG Gaocheng LIU Xianli 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第5期921-929,共9页
Laser assisted machining is an effective method to machine advanced materials with the added benefits of longer tool life and increased material removal rates. While extensive studies have investigated the machining p... Laser assisted machining is an effective method to machine advanced materials with the added benefits of longer tool life and increased material removal rates. While extensive studies have investigated the machining properties for laser assisted milling(LAML), few attempts have been made to extend LAML to machining parts with complex geometric features. A methodology for continuous path machining for LAML is developed by integration of a rotary and movable table into an ordinary milling machine with a laser beam system. The machining strategy and processing path are investigated to determine alignment of the machining path with the laser spot. In order to keep the material removal temperatures above the softening temperature of silicon nitride, the transformation is coordinated and the temperature interpolated, establishing a transient thermal model. The temperatures of the laser center and cutting zone are also carefully controlled to achieve optimal machining results and avoid thermal damage. These experiments indicate that the system results in no surface damage as well as good surface roughness, validating the application of this machining strategy and thermal model in the development of a new LAML system for continuous path processing of silicon nitride. The proposed approach can be easily applied in LAML system to achieve continuous processing and improve efficiency in laser assisted machining. 展开更多
关键词 laser assisted milling laser assisted milling device silicon nitride ceramic finite element analysis heat transfer
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Study on Characteristic of Electric Power Assist Steering System 被引量:1
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作者 许镇琳 王豪 +2 位作者 尚喆 张海华 王家军 《Transactions of Tianjin University》 EI CAS 2003年第3期211-213,共3页
A pinion-type electric power steering (EPS) equipped on a sedan is reached in this paper. A three-freedom dynamic model of this system is created. The variables affecting assist character is analyzed. The formulas of ... A pinion-type electric power steering (EPS) equipped on a sedan is reached in this paper. A three-freedom dynamic model of this system is created. The variables affecting assist character is analyzed. The formulas of simpled steering resistance force and the relationship between assist gain and vehicle speed are presented for the first time. Assist character is found based on the parameters of a sedan at last. This assist character is fit for the control rule of the EPS system through analyzing this character. The assist character figure offers reference for system design and control. Furthermore, this research method has generality for assist character of different kinds of vehicles. 展开更多
关键词 VEHICLE electric power steering assist steering assist characteristic
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AMORPHIZATION IN Nb-M (M=Fe, Co, Ni) BINARY METAL SYSTEMS INDUCED BY ION BEAM ASSISTED DEPOSITION (IBAD) 被引量:1
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作者 F.Pan, F. Zeng and B. Zhao Laboratory of Advanced Materials, Department of Materials and Engineering, Tsinghua University, Beijing 100084, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2002年第2期160-166,共7页
Ion beam assisted deposition technique (IBAD) was utilized to systematically study amorphization in binary metal systems of Nb-magnetic element, i.e., Nb-M (M=Fe, Co or Ni). The glass forming range termed as Nb fracti... Ion beam assisted deposition technique (IBAD) was utilized to systematically study amorphization in binary metal systems of Nb-magnetic element, i.e., Nb-M (M=Fe, Co or Ni). The glass forming range termed as Nb fraction of Nb-Fe system was about 34at.% to 56at.%, that of Nb-Co system was about 32at.% to 72at.% and that of Nb-Ni about 20at. % to 80at. %. Similar percolation patterns were found in amorphous alloy films. The fractal dimensions of the percolation patterns approach to 2, which indicates 2-D layer growth for amorphous phases. It is regarded that the assisted Ar+ ion beam during the deposition process plays important role for the 2-D layer growth. Some metastable crystalline phases were obtained in these three systems by IBAD, e.g., bcc supersaturated solid solutions in Nb-Fe and Nb-Co systems, fcc and hcp phases in Nb-Co and Nb-Ni systems. The formation and competing between the amorphous and the metastable crystalline phases were determined by both the phases' thermodynamic states in binary metal systems and kinetics during IBAD process. 展开更多
关键词 amorphization ion beam assisted deposition glass forming range metastable phase
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A real-time AI-assisted seismic monitoring system based on new nodal stations with 4G telemetry and its application in the Yangbi M_(S) 6.4 aftershock monitoring in southwest China 被引量:2
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作者 Junlun Li Huajian Yao +10 位作者 Baoshan Wang Yang Yang Xin Hu Lishu Zhang Beng Ye Jun Yang Xiaobin Li Feng Liu Guoyi Chen Chang Guo Wen Yang 《Earthquake Research Advances》 CSCD 2022年第2期3-10,共8页
A rapidly deployable dense seismic monitoring system which is capable of transmitting acquired data in real time and analyzing data automatically is crucial in seismic hazard mitigation after a major earthquake.Howeve... A rapidly deployable dense seismic monitoring system which is capable of transmitting acquired data in real time and analyzing data automatically is crucial in seismic hazard mitigation after a major earthquake.However,it is rather difficult for current seismic nodal stations to transmit data in real time for an extended period of time,and it usually takes a great amount of time to process the acquired data manually.To monitor earthquakes in real time flexibly,we develop a mobile integrated seismic monitoring system consisting of newly developed nodal units with 4G telemetry and a real-time AI-assisted automatic data processing workflow.The integrated system is convenient for deployment and has been successfully applied in monitoring the aftershocks of the Yangbi M_(S) 6.4 earthquake occurred on May 21,2021 in Yangbi County,Dali,Yunnan in southwest China.The acquired seismic data are transmitted almost in real time through the 4G cellular network,and then processed automat-ically for event detection,positioning,magnitude calculation and source mechanism inversion.From tens of seconds to a couple of minutes at most,the final seismic attributes can be presented remotely to the end users through the integrated system.From May 27 to June 17,the real-time system has detected and located 7905 aftershocks in the Yangbi area before the internal batteries exhausted,far more than the catalog provided by China Earthquake Networks Center using the regional permanent stations.The initial application of this inte-grated real-time monitoring system is promising,and we anticipate the advent of a new era for Real-time Intelligent Array Seismology(RIAS),for better monitoring and understanding the subsurface dynamic pro-cesses caused by Earth's internal forces as well as anthropogenic activities. 展开更多
关键词 Seismic dense array 4G data transmission Real-time earthquake monitoring Machine-learning assisted processing Real-time intelligent array seismology
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FPGA-Based Traffic Sign Recognition for Advanced Driver Assistance Systems 被引量:1
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作者 Sheldon Waite Erdal Oruklu 《Journal of Transportation Technologies》 2013年第1期1-16,共16页
This paper presents the implementation of an embedded automotive system that detects and recognizes traffic signs within a video stream. In addition, it discusses the recent advances in driver assistance technologies ... This paper presents the implementation of an embedded automotive system that detects and recognizes traffic signs within a video stream. In addition, it discusses the recent advances in driver assistance technologies and highlights the safety motivations for smart in-car embedded systems. An algorithm is presented that processes RGB image data, extracts relevant pixels, filters the image, labels prospective traffic signs and evaluates them against template traffic sign images. A reconfigurable hardware system is described which uses the Virtex-5 Xilinx FPGA and hardware/software co-design tools in order to create an embedded processor and the necessary hardware IP peripherals. The implementation is shown to have robust performance results, both in terms of timing and accuracy. 展开更多
关键词 TRAFFIC SIGN Recognition Advanced DRIVER assistANCE systems Field PROGRAMMABLE GATE Array (FPGA)
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Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid 被引量:2
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作者 Yusuf Suleiman Dambatta Changhe Li +8 位作者 Mohd Sayuti Ahmed A D Sarhan Min Yang Benkai Li Anxue Chu Mingzheng Liu Yanbin Zhang Zafar Said Zongming Zhou 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期115-136,共22页
Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL ... Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics. 展开更多
关键词 Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants NANOFLUID GRINDING CERAMIC
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Effects of equine-assisted interventions on older adults’health:A systematic review
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作者 Léa Badin Émilie Alibran +1 位作者 Kristell Pothier Nathalie Bailly 《International Journal of Nursing Sciences》 CSCD 2022年第4期542-552,共11页
Objective:Equine-assisted interventions(EAI)can improve a variety of health problems in older adults and thus promote their well-being.This systematic review aimed to synthesize studies on EAI to understand better the... Objective:Equine-assisted interventions(EAI)can improve a variety of health problems in older adults and thus promote their well-being.This systematic review aimed to synthesize studies on EAI to understand better their effects on the health of older adults.Method:A systematic search guided by the PRISMA 2020 approach was performed on specific databases:Medline(PubMed),EMBASE,PsycINFO,and Cochrane Library.Peer-reviewed articles published in the English language from inception to June 2022 were retrieved.Methodological quality was established using the modified version of the Downs and Black checklist.Results:A total of 244 studies were retrieved,and 13 eligible studies were finally included.Three health domains were investigated:physical(balance,gait,and muscular strength),psychological(quality of life and cognitive assessment),and physiological(hormonal measures,cerebral and muscular activity).Among the eight studies investigating the physical dimension,four studies highlighted a positive effect of EAI on balance,four for gait,and three for strength.Regarding the three studies investigating the psychological dimension,two studies showed a positive effect of EAI on quality of life.Lastly,the four studies investigating the physiological dimensions all demonstrated a positive effect of EAI on hormonal measures and cerebral and muscular activity.Conclusion:Nevertheless,this systematic review provides promising findings regarding the positive effects of EAI on physical,psychological,and physiological health in older adults.Research on EAI should therefore be pursued rigorously to promote this non-pharmacological intervention in an older adult population. 展开更多
关键词 Animal assisted therapy Aged Equine assisted therapy Health promotion
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A Wire-Driven Series Elastic Mechanism Based on Ultrasonic Motor for Walking Assistive System
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作者 Weihao Ren Hiroki Yoshioka +1 位作者 Lin Yang Takeshi Morita 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期179-190,共12页
In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assi... In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising technology.Therefore,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this research.In contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force control.The proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating part.To overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear reducer.Among the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 constantly.Meanwhile,the prototype is manufactured and its actual performance is verified by experimental results.In a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·m.At this torque,the ultrasonic motor's speed is around 4.1 rad/s.Moreover,experiments with different operation periods have been conducted for different application scenarios.This study provides a useful idea for the application of ultrasonic motor in walking assistance system. 展开更多
关键词 Ultrasonic motor WIRE-DRIVEN Series elastic mechanism Walking assistive system Pulley Reduction ratio
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A New hcp Phase Formed in the Ni-Nb System during Ion-beam-assisted Deposition
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作者 Bin ZHAO, Kuiwei GENG, Fei ZENG and Feng PANLaboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第5期577-579,共3页
The Ni80Nb20 films were prepared by ion beam assisted deposition (IBAD) with various Ar+ ion energies. A phase evolution of fcc→amorphous→Ni+Nb→Ni+hcp was observed with the increasing of ion beam energy from 2 keV ... The Ni80Nb20 films were prepared by ion beam assisted deposition (IBAD) with various Ar+ ion energies. A phase evolution of fcc→amorphous→Ni+Nb→Ni+hcp was observed with the increasing of ion beam energy from 2 keV to 8 keV. When bombarded by Ar+ ions of 8 keV during deposition, a new crystalline phase with hcp structure was obtained, of which the lattice parameters are a=0.286 nm and c=0.483 nm, different from those of the similar A3B-type hcp phase previously reported. The experimental results were discussed in terms of thermodynamics and restricted kinetic conditions in the far-from-equilibrium process of IBAD. The formation of hep phase may also be related to the valence electron effect. 展开更多
关键词 Hcp phase Ni-Nb Ion beam assisted deposition THERMODYNAMICS Valence electron effect
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