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Holographic alloy positioning design system and holographic network phase diagrams of Au-Cu system 被引量:3
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作者 谢佑卿 刘心笔 +2 位作者 李小波 彭红建 聂耀庄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期885-906,共22页
Taking Au?Cu system as an example, three discoveries and two methods were presented. First, a new way for boosting sustainable progress of systematic metal materials science (SMMS) and alloy gene engineering (AGE) is ... Taking Au?Cu system as an example, three discoveries and two methods were presented. First, a new way for boosting sustainable progress of systematic metal materials science (SMMS) and alloy gene engineering (AGE) is to establish holographic alloy positioning design (HAPD) system, of which the base consists of measurement and calculation center, SMMS center, AGE center, HAPD information center and HAPD cybernation center; Second, the resonance activating-sychro alternating mechanism of atom movement may be divided into the located and oriented diffuse modes; Third, the equilibrium and subequilibrium holographic network phase diagrams are blueprints and operable platform for researchers to discover, design, manufacture and deploy advanced alloys, which are obtained respectively by the equilibrium lever numerical method and cross point numerical method of isothermal Gibbs energy curves. As clicking each network point, the holographic information of three structure levels for the designed alloy may be readily obtained: the phase constitution and fraction, phase arranging structure and properties of organization; the composition, alloy gene arranging structure and properties of each phase and the electronic structures and properties of alloy genes. It will create a new era for network designing advanced alloys. 展开更多
关键词 Au-Cu system holographic alloy positioning design system equilibrium and subequilibrium holographic network phase diagrams systematic metal materials science network designing advanced alloys
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Positioning and design by computed tomography imaging in neuroendoscopic surgery of patients with chronic subdural hematoma
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作者 Xue-Jian Wang Yu-Hua Yin +3 位作者 Long-Yao Zhang Zhi-Feng Wang Cheng Sun Zhi-Ming Cui 《World Journal of Clinical Cases》 SCIE 2023年第14期3204-3210,共7页
BACKGROUND Neuroendoscopy is a very useful technique to Chronic Subdural Hematoma(CSH).But how to achieve the goal of treatment more minimally invasive?AIM To develop a simple,fast and accurate preoperative planning m... BACKGROUND Neuroendoscopy is a very useful technique to Chronic Subdural Hematoma(CSH).But how to achieve the goal of treatment more minimally invasive?AIM To develop a simple,fast and accurate preoperative planning method in our way for endoscopic surgery of patients with CSH.METHODS From June 2018 to May 2020,forty-two patients with CSH,admitted to our hospital,were performed endoscopic minimally invasive surgery;computed tomography(CT)imaging was employed to locate the intracerebral hematoma and select the appropriate endoscopic approach before the endoscopic surgery.The clinical data and treatment efficacy were analyzed.RESULTS According to the learning of CT scanning images,the surgeon can accurately design the best minimally invasive neuroendoscopic surgical approach and realize the precise positioning and design of the drilling site of the skull and the size of the bone window,so as to provide the most effective operation space with the smallest bone window.In this group,the average operation time was only about 1 h,and the clearance rate of hematoma was about 95%.CONCLUSION Patients with CSH can achieve good therapeutic effect by using our way to positioning and design to assist the operation of CSH according to CT scan and image,and our way is very useful and necessary. 展开更多
关键词 Chronic subdural hematoma Neurosurgery neuroendoscopy positioning and design Bone window design
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The Design and Implementation of High-rise Building Construction Based on GPS Positioning Technology
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作者 Deng Hui 《Journal of Architectural Research and Development》 2018年第1期1-5,共5页
Baseline observation as well as height measurement is the important content of the quality control of high-rise building construction.In order to strengthen the quality of construction projects,meet the requirement of... Baseline observation as well as height measurement is the important content of the quality control of high-rise building construction.In order to strengthen the quality of construction projects,meet the requirement of completion time,improve the accuracy and efficiency of locating observation and explore a scientific way of observation suitable for high-rise building construction,this paper studies the design and implementation of high-rise building construction based on GPS positioning technology. 展开更多
关键词 HIGH-RISE BUILDING CONSTRUCTION GPS positioning technology design implementation
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Optomechanical Design for Precision Lens Positioning and Mounting
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作者 Shuping Wang Chi Zhang +3 位作者 Mark Alt Colleen Davis Michael L. Gardner Zheng Ji 《Optics and Photonics Journal》 2016年第8期1-7,共7页
The proper choice of optomechanical components along with alignment techniques is vital to the successful implementation of lens positioning and mounting. In general, there is a trade-off between lens positioning accu... The proper choice of optomechanical components along with alignment techniques is vital to the successful implementation of lens positioning and mounting. In general, there is a trade-off between lens positioning accuracy and manufacturing cost. In order to achieve optimal precision- to-cost ratio, a careful optomechanical design together with accurate alignment and assembly is necessary. This paper presents a lens positioning and mounting in a few microns accuracy using a kinematic mount module. The optomechanical design of the kinematic mount module and the associated fixtures based on the simulation study of components sensitivity are presented. The processes for alignment and assembly, which separate decenter from tip-tilt, are developed and presented. Finally, the prototypes are created and testing results are presented. The optomechanical design that allows the separation of decenter from tip-tilt considerably simplifies the positioning and assembly process and reduces the cost for mass production. 展开更多
关键词 Optomechanical design Lens Mount Lens positioning
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Research on the Architectural Design Positioning of University Halls
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作者 Haixiu Liang Jiantao Huang 《Journal of Architectural Research and Development》 2021年第6期25-32,共8页
University hall is an important carrier of information exchange and sharing in higher education campuses,and the correct architectural design positioning can improve the value of university halls.There are many differ... University hall is an important carrier of information exchange and sharing in higher education campuses,and the correct architectural design positioning can improve the value of university halls.There are many different features in the design and use of university halls and urban theaters.This paper investigates the feasibility study report and indexes of university hall projects,analyzes the indexes,construction scale and functional positioning of university halls in the pre-design period,summarizes some design suggestions,and believes that the use efficiency of university halls should be improved through intensive and compound construction to meet the needs of the rapid development of Chinas Universitys and universities. 展开更多
关键词 University hall design positioning Architectural design INTENSIVE
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Experimental Investigation and Optimization Design of Multi-Support Pipeline System 被引量:12
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作者 Xiantao Zhang Wei Liu +1 位作者 Yamei Zhang Yujie Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第2期135-149,共15页
The design of aircraft hydraulic pipeline system is limited by many factors,such as the integrity of aviation structure or narrow installation space,so the limited clamp support position should be considered.This pape... The design of aircraft hydraulic pipeline system is limited by many factors,such as the integrity of aviation structure or narrow installation space,so the limited clamp support position should be considered.This paper studied the frequency adjustment and dynamic responses reduction of the multi-support pipeline system through experiment and numerical simulation.To avoid the resonance of pipeline system,we proposed two different optimization programs,one was to avoid aero-engine working range,and another was to avoid aircraft hydraulic pump pulsation range.An optimization method was introduced in this paper to obtain the optimal clamp position.The experiments were introduced to validate the optimization results,and the theoretical optimization results can agree well with the test.With regard to avoiding the aero-engine vibration frequency,the test results revealed that the first natural frequency was far from the aero-engine vibration frequency.And the dynamic frequency sweep results showed that no resonance occurred on the pipeline in the engine vibration frequency range after optimization.Additionally,with regard to avoiding the pump vibration frequency,the test results revealed that natural frequencies have been adjusted and far from the pump vibration frequency.And the dynamic frequency sweep results showed that pipeline under optimal clamp position cannot lead to resonance.The sensitivity analysis results revealed the changing relationships between different clamp position and natural frequency.This study can provide helpful guidance on the analysis and design of practical aircraft pipeline. 展开更多
关键词 Multi-support pipeline system Clamp position optimization Frequency adjustment design Dynamic responses
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Simulation-based Optimal Design of α-β-γ-δ Filter 被引量:1
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作者 Chun-Mu Wu Paul P. Lin +1 位作者 Zhen-Yu Han Shu-Rong Li 《International Journal of Automation and computing》 EI 2010年第2期247-253,共7页
The existing third-order tracker known as α-β-γ-δ filter has been used for target tracking and predicting for years. The filter can track the target's position and velocity, but not the acceleration. To extend it... The existing third-order tracker known as α-β-γ-δ filter has been used for target tracking and predicting for years. The filter can track the target's position and velocity, but not the acceleration. To extend its capability, a new fourth-order target tracker called α-β-γ-δ filter is proposed. The main objective of this study was to find the optimal set of filter parameters that leads to minimum position tracking errors. The tracking errors between using the α-β-γ-δ filter and the α-β-γ-δ filter are compared. As a result, the new filter exhibits significant improvement in position tracking accuracy over the existing third-order filter, but at the expense of computational time in search of the optimal filter. To reduce the computational time, a simulation-based optimization technique via Taguchi method is introduced. 展开更多
关键词 Filter design simulation-based optimization Taguchi methods position tracking velocity tracking acceleration tracking.
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Asynchronous Observer Design for Switched Linear Systems: A Tube-Based Approach 被引量:2
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作者 Minghao Han Ruixian Zhang +2 位作者 Lixian Zhang Ye Zhao Wei Pan 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期70-81,共12页
This paper proposes a tube-based method for the asynchronous observation problem of discrete-time switched linear systems in the presence of amplitude-bounded disturbances.Sufficient stability conditions of the nomina... This paper proposes a tube-based method for the asynchronous observation problem of discrete-time switched linear systems in the presence of amplitude-bounded disturbances.Sufficient stability conditions of the nominal observer error system under mode-dependent persistent dwell-time(MPDT)switching are first established. Taking the disturbances into account, a novel asynchronous MPDT robust positive invariant(RPI) set and an asynchronous MPDT generalized RPI(GRPI)set are determined for the difference system between the nominal and disturbed observer error systems. Further, the global uniform asymptotical stability of the observer error system is established in the sense of converging to the asynchronous MPDT GRPI set, i.e., the cross section of the tube of the observer error system. Finally, the proposed results are validated on a space robot manipulator example. 展开更多
关键词 Asynchronous observer design generalized robust positive invariant(GRPI) set mode-dependent persistent dwell-time(MPDT) switched linear systems
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Beam Position and Beam Hopping Design for LEO Satellite Communications 被引量:1
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作者 Leyi Lyu Chenhao Qi 《China Communications》 SCIE CSCD 2023年第7期29-42,共14页
The numbers of beam positions(BPs)and time slots for beam hopping(BH)dominate the latency of LEO satellite communications.Aiming at minimizing the number of BPs subject to a predefined requirement on the radius of BP,... The numbers of beam positions(BPs)and time slots for beam hopping(BH)dominate the latency of LEO satellite communications.Aiming at minimizing the number of BPs subject to a predefined requirement on the radius of BP,a low-complexity user density-based BP design scheme is proposed,where the original problem is decomposed into two subproblems,with the first one to find the sparsest user and the second one to determine the corresponding best BP.In particular,for the second subproblem,a user selection and smallest BP radius algorithm is proposed,where the nearby users are sequentially selected until the constraint of the given BP radius is no longer satisfied.These two subproblems are iteratively solved until all the users are selected.To further reduce the BP radius,a duplicated user removal algorithm is proposed to decrease the number of the users covered by two or more BPs.Aiming at minimizing the number of time slots subject to the no co-channel interference(CCI)constraint and the traffic demand constraint,a low-complexity CCI-free BH design scheme is proposed,where the BPs having difficulty in satisfying the constraints are considered to be illuminated in priory.Simulation results verify the effectiveness of the proposed schemes. 展开更多
关键词 beam hopping(BH)design beam position(BP)design low earth orbit(LEO) low latency satellite communications
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Ecological Planning and Design of Urban Green Space System of Sanya City 被引量:1
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作者 WANG Shengnan YANG Dan WEI Xuan 《Journal of Landscape Research》 2015年第4期13-16,19,共5页
The construction of International Tourism Island has accelerated the development of Sanya City. The population aggregation and the external extension of urban area have brought a lot of negative effects, such as disco... The construction of International Tourism Island has accelerated the development of Sanya City. The population aggregation and the external extension of urban area have brought a lot of negative effects, such as discontinuities of green space matrix, dysfunction of green wedge permeation, deficiency of eco-corridor, structural imbalance of green space system and so on. The overall layout of Green space system known as "One Belt & Three Bays, One Core & Six Towns, Two Axes & Three Wedges, Two Net Synchronous-construction" strengthens the eco-connection among different groups and green space in central area of the city, and realizes the collaborative construction of both resource corridor and landscape corridor. The eco-layout of green core, green corridor and green patch helps keep the integrity of large vegetation patches, enhances the eco-connection of different types of green space and improves finger-shaped network of urban green space. The most efficient way to promote the circulation of urban ecosystem and the positive development of Sanya City is to plan multilevel and three-dimensional eco-space structure and maximize ecological benefits of green space system. 展开更多
关键词 Green space system Ecological plan & design Urban district Sanya
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The design of multi-function nursing wheelchair 被引量:2
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作者 LI Xiaoman WANG Zhengxing +2 位作者 ZHANG Shuai LI Fei ZHANG Li 《Computer Aided Drafting,Design and Manufacturing》 2013年第1期68-70,共3页
In order to reduce nursing intensity and improve freedom of the elderly and the disabled, a multi-function nursing wheelchair which can switch chair to bed and realize many kinds of posture transformation is designed.... In order to reduce nursing intensity and improve freedom of the elderly and the disabled, a multi-function nursing wheelchair which can switch chair to bed and realize many kinds of posture transformation is designed. This paper introduces the mechanical structure design (position adjustment mechanism and variable wheelbase mechanism) and control design of posture transformation unit of multifunctional nursing wheelchair. 展开更多
关键词 posture transformation position adjustment mechanism variable wheelbase the control system design
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Angular Position Controller and Its Design Model Verification for the Electro-Hydraulic Servo Control System 被引量:1
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作者 KARAM M. Elbayomy 《Computer Aided Drafting,Design and Manufacturing》 2007年第1期60-65,共6页
The angular position controller is system (EHSAS) to control the output of the rotary applied to electro-hydraulic servo actuator actuator. It works as a compensator based on the frequency response of the EHSAS. Its... The angular position controller is system (EHSAS) to control the output of the rotary applied to electro-hydraulic servo actuator actuator. It works as a compensator based on the frequency response of the EHSAS. Its design model is verified on the state-space model of EHSAS by using simulation program SIMULINK. Real data used to test the system. Simulation results give a good agreement for the controller and also for the state-space model. 展开更多
关键词 angular position controller electro-hydraulic servo control system design model state-space model SIMULINK
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Precision Design for Machine Tool Based on Error Prediction 被引量:5
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作者 HUANG Qiang ZHANG Genbao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第1期151-157,共7页
Digitization precision analysis is an important tool to ensure the design precision of machine tool currently. The correlative research about precision modeling and analysis mainly focuses on the geometry precision an... Digitization precision analysis is an important tool to ensure the design precision of machine tool currently. The correlative research about precision modeling and analysis mainly focuses on the geometry precision and motion precision of machine tool, and the forming motion precision of workpiece surface. For the machine tool with complex forming motion, there is not accurate corresponding relationship between the existing criterion on precision design and the machining precision of workpiece. Therefore, a design scheme on machine tool precision based on error prediction is proposed, which is divided into two-stage digitization precision analysis crucially. The first stage aims at the technology system to complete the precision distribution and inspection from the workpiece to various component parts of technology system and achieve the total output precision of machine tool under the specified machining precision; the second stage aims at the machine tool system to complete the precision distribution and inspection from the output precision of machine tool to the machine tool components. This article serves YK3610 gear hobber as the example to describe the error model of two systems and basic application method, and the practical cutting precision of this machine tool achieves to 5-4-4 grade. The proposed method can provide reliable guidance to the precision design of machine tool with complex forming motion. 展开更多
关键词 complex forming motion machine tool precision design position-pose error error sensibility
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Analysis of the Development Strategy of China Petroleum Design & Engineering Company
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作者 ZhangBaosheng 《Petroleum Science》 SCIE CAS CSCD 2004年第1期83-89,96,共8页
China Petroleum Design & Engineering Company (CPDEC) is a new corporation established in the year 2001. The company puts forward its development objectives for becoming a first-class national and international des... China Petroleum Design & Engineering Company (CPDEC) is a new corporation established in the year 2001. The company puts forward its development objectives for becoming a first-class national and international desigh firm within 5 to 10 years. In this paper, the theories and techniques related to the business environment and strategy are used to make an analysis of the companys development objectives. According to the analysis of the environment and internal conditions of CPDEC, we suggest adoping the strategic measures for reaching the development objectives on the basis of the SWOT (the acronym of Strengths, Weaknesses, Opportunities and Threats) analysis method. Some conclusions and recommendations on the companys situation and strategies are given. 展开更多
关键词 design & engineering company development strategy business environment
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Landscape Planning & Design of Small Townlet in Ethnic Area
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作者 吴威龙 《Journal of Landscape Research》 2009年第6期9-11,共3页
In this study, the overall planning of Ji Townlet in Jianshan Town, Tujia-Miao Autonomous Prefecture was analyzed. The landscape planning & design of small townlets combined with the natural environment, humanist ... In this study, the overall planning of Ji Townlet in Jianshan Town, Tujia-Miao Autonomous Prefecture was analyzed. The landscape planning & design of small townlets combined with the natural environment, humanist resources and ethnic features in ethnic area were discussed. 展开更多
关键词 ETHNIC area SMALL townlet LANDSCAPE PLANNING & design
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BIM in Multifamily Design &Construction
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作者 Matt Jefferies Swarnali Ghosh Dastider 《Journal of Building Construction and Planning Research》 2018年第4期331-339,共9页
In 2014, the National Association of Homebuilders conducted an initial survey about the use of Building Information Modeling (BIM) in residential construction. They found that BIM had not been widely adopted, but ther... In 2014, the National Association of Homebuilders conducted an initial survey about the use of Building Information Modeling (BIM) in residential construction. They found that BIM had not been widely adopted, but there was interest in future use. Four years later, the authors, Prof. Ghosh Dastider and Matt Jefferies at Washington University in St. Louis used a similar methodology to see what has changed. They found a significant increase in BIM’s application in the multifamily residential industry. Based on data collected from the re-conducted survey, the authors concluded with the future predictions on how use of BIM will accelerate in residential construction market in next few years. Few significant findings indicate increased use of BIM among contractors along with design built firms, as well as during the construction phase and life cycle analysis. 展开更多
关键词 BIM MULTIFAMILY design & CONSTRUCTION HIGH-RISE RESIDENTIAL Technology
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Study on Design Rainstorm Profile in Liuzhou City Based on Pilgrim &Cordery Method
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作者 Xiaoling Su Dong Xie +5 位作者 Lei Liu Chunrong Liang Zhourong Liu Yu Li Qiu Lan Le Ren 《Journal of Geoscience and Environment Protection》 2019年第3期136-144,共9页
Liuzhou City is located in Guangxi Zhuang Autonomous Region of China. It has a warm and rainy climate and belongs to the middle subtropical monsoon climate. It is a rainstorm and flood-prone area. The work of flood dr... Liuzhou City is located in Guangxi Zhuang Autonomous Region of China. It has a warm and rainy climate and belongs to the middle subtropical monsoon climate. It is a rainstorm and flood-prone area. The work of flood drainage and waterlogging prevention is very important. The “minute to minute” rainfall process data of Liuzhou National Meteorological Observation Station from 1975 to 2014 and the Pilgrim & Cordery method were used to estimate the short-time design rainstorm profile of Liuzhou City, and the profiles of the rainfall lasting for 30, 60, 90, 120, 150, and 180 min were obtained. The research shows that the same rain duration and different recurrence period conditions are consistent with the rainstorm profile. The rainfall duration of 30, 60, 90, 120, and 180 min generally shows single-peak rainstorm profile, and the rainfall duration of 150 min shows double-peak rainstorm profile. Most peaks of each short-time design rainstorm profile are at or ahead of the 1/3 part of the entire rainfall process. During the same recurrence period, the rainfall in peak period fluctuated with the increase of the duration, and the intensity of rainfall increased with the prolonging of the recurrence period. 展开更多
关键词 Liuzhou CITY PILGRIM & Cordery METHOD Short-Time RAINSTORM design RAINSTORM PROFILE
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Quantifying Design Parameters of Symbology Page for Automotive Head up Display
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作者 Gupta Sharad Karar Vinod +2 位作者 Saini Surender Singh Jaggi Neena Bajpai Phun Phun 《Computer Technology and Application》 2011年第8期658-662,共5页
This paper gives an overview of studies on parameters displayed on the Automotive Head Up Display (A-HUD) including calculation and construction of symbology page based on study results. A study has been made on vit... This paper gives an overview of studies on parameters displayed on the Automotive Head Up Display (A-HUD) including calculation and construction of symbology page based on study results. A study has been made on vital parameters required for car drivers and design calculations have been made based on design parameters like field of view, distance from the design eye position, minimum character size viewable from a distance of 1.5m between driver and the projected image, and optical magnification factor. lhe display format suitable for A-HUD applications depends upon the parameters required to be displayed. The aspect ratio chosen is 4:3. This paper also provides method to design the symbology page embedding six vital parameters with their relative positioning and size considering relative position between display device and optical elements which has been considered with a magnification factor of 2.5. The field of view obtained is 6.7° × 4.8°. 展开更多
关键词 Automotive head up display (A-HUD) MAGNIFICATION symbology character size human factors field of view (FOV). design eye position (DEP).
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An Implementation Technique for Multivariate Robust Design
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作者 MAYi-zhong ZHAOFeng-yu 《International Journal of Plant Engineering and Management》 2005年第1期47-53,共7页
This paper investigates systematically the problem of multivariate robustparameter design. First, a measurement criterion for the total variation of multivariate qualitycharacteristics is introduced by the result of i... This paper investigates systematically the problem of multivariate robustparameter design. First, a measurement criterion for the total variation of multivariate qualitycharacteristics is introduced by the result of information theory. Then the implementation procedurein the robust design is presented. After that, a simulation example from a practical industrialprocess is provided. Finally, some comments and further work are discussed. 展开更多
关键词 multivariate robust design implementation procedure positive analysis
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多体位智能轮椅床椅转换装置的运动学仿真分析 被引量:2
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作者 张爽 李建永 +2 位作者 李作家 罗春阳 孙永强 《林产工业》 北大核心 2024年第2期43-47,79,共6页
介绍了多体位智能轮椅的坐、躺、立、蹲、行5种姿态的转换功能,对床椅转换装置进行简化处理,建立背板机构的运动学模型,利用MATLAB对模型进行计算,得到背板的角速度和角加速度时间的运动曲线。利用ADAMS对优化后的装置模型进行运动学分... 介绍了多体位智能轮椅的坐、躺、立、蹲、行5种姿态的转换功能,对床椅转换装置进行简化处理,建立背板机构的运动学模型,利用MATLAB对模型进行计算,得到背板的角速度和角加速度时间的运动曲线。利用ADAMS对优化后的装置模型进行运动学分析,得到改进后床椅转换装置的运动曲线。结果表明:该装置具有较好的运动学性能,在床椅转换过程中背板的最大角加速度达到了16°/s^(2),小于人体所能承受的最大角加速度50°/s^(2)。改进后,床椅平稳转换的时间有所延长,转换过程耗时7.5 s,在0.7~6.9 s内,背板运动趋于加速度接近0的平稳运动,表明推杆速度设计合理。 展开更多
关键词 失能老人 多体位变换 模块化设计 床椅转换 运动学分析
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