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期刊论文 34

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光栅干涉仪;光学编码器;位移测量;精密测量 1

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Research on physical shape preserving curve reconstruction

TANG Kelun, ZHANG Xiangwei, CHENG Siyuan, XIONG Hanwei, ZHANG Hong

《机械工程前沿(英文)》 2007年 第2卷 第3期   页码 305-309 doi: 10.1007/s11465-007-0054-2

摘要: Fusion of various data is an effective way to improve the precision and efficiency of acquiring information in reverse engineering. A method of physical shape preserving curve reconstruction is proposed to better realize the data fusion of coordinate measuring machine (CMM) and visual information. From the principle of materials mechanics, the strain energy of the curve corresponding to the distortion is advanced as the internal energy, and the elastic potential energy of the curve is established, using a few precise measured data points as the equilibrium position, to be the external energy. On the basis of the principle of variation calculus, the basic spline finite element method (B-spline FEM) is used to determine the equilibrium position of curve deformation. Numerical simulation indicates that there is an extremely good agreement between the new fitted curve and the actual curve.

关键词: information     CMM     Numerical simulation     effective     coordinate measuring    

New form of geodetic coordinate system taking two length quantity as coordinate parameters

Yimin SHI, Ziyang ZHU, Yeming FAN

《结构与土木工程前沿(英文)》 2009年 第3卷 第1期   页码 105-110 doi: 10.1007/s11709-009-0014-5

摘要: A new form of geodetic coordinate system based on geodesic coordinates instead of geodetic longitude and latitude was proposed. The vertical and horizontal geodesic coordinates measured with length were defined as coordinate parameters, but the two families of coordinate curves were still meridians and parallel circles. The first fundamental form on the ellipsoidal surface and its three coefficients were deduced by the geodesic coordinate. The formula for the latitudinal scale factor of length for geodetic parallel lines was derived, by which the obtained result conformed to that standard value calculated from geodetic latitude, and it is applicable in the range of 400 km from north to south. Therefore, it lays the foundation for establishing the differential equation and differential relationship based on this type of coordinate parameters; and consequently, it is convenient and accurate enough to operate on the ellipsoidal surface in this new form of geodetic coordinate system.

关键词: geodetic coordinate system     meridian and parallel circle     coordinate parameter     the first fundamental form on the ellipsoidal surface     latitudinal scale factor of length    

Comparison of analytical procedures for measuring phosphorus content of animal manures in China

null

《农业科学与工程前沿(英文)》 2019年 第6卷 第4期   页码 431-440 doi: 10.15302/J-FASE-2019279

摘要:

The concentration and components of manure phosphorus (P) are key factors determining potential P bioavailability and runoff. The distribution of P forms in swine, poultry and cattle manures collected from intensive and extensive production systems in several areas of China was investigated with sequential fractionation and a simplified two-step (NaHCO -NaOH/EDTA) procedures. The mean total P concentration, determined by the sequential fractionation procedure of intensive swine, poultry and cattle manure, expressed as g·kg , was 14.9, 13.4 and 5.8 g·kg , respectively, and 4.4 g·kg in extensive cattle manure. In intensive swine, poultry and cattle manure about 73%, 74% and 79% of total P, respectively, was bioavailable (i.e., P extracted by H O and NaHCO ) and 78% in extensive cattle manure. The results indicated the relative environmental risk, from high to low, of swine, poultry and cattle manure. There is considerable regional variation in animal manure P across China, which needs to be considered when developing manure management strategies.

关键词: diet phosphorus     manure phosphorus     sequential P fractionation    

A feasibility study of the measuring accuracy and capability of wireless sensor networks in tunnel monitoring

Xiaojun LI, Zhong JI, Hehua ZHU, Chen GU

《结构与土木工程前沿(英文)》 2012年 第6卷 第2期   页码 111-120 doi: 10.1007/s11709-012-0150-1

摘要: Fire disasters and the deterioration of tunnel structures are major concerns for tunnel operation and maintenance. Traditional wired monitoring systems have many drawbacks in terms of installation time, overall cost, and flexibility in tunnel environments. In recent years, there has been growing interest in the use of wireless sensor networks (WSNs) for the monitoring of various structural monitoring applications. This paper evaluated the feasibility of applying a WSN in the monitoring of tunnels. The monitoring requirements of tunnels under explosion and combustion fire scenarios are analyzed using numerical simulation, and the maximum possible distance for temperature sensors is derived. The displacement monitoring of tunnels using an inclinometer is investigated. It is recommended that the inclinometer should be installed in the 1/4 span of the tunnel structure. The maximum wireless transmission distances in both outdoor and tunnel environments were examined. The influences of surface materials and sensor node locations on the data transmission distance in tunnel environments were also investigated. The experimental results show that the data loss in tunnel environments is approximately three times that in outdoor environments. Surface material has a considerable influence on the transmission distance of radio signals. The distance is 25 ? 28 m for a raw concrete surface, 20 m for a brick surface, and 36 m for a terrazzo surface. The transmission distances along the middle of quarter points are approximately 0.9 ( is the transmission distance in the center of the tunnel), and the relative error is less than±3%. The transmission distances at different locations along the bottom exhibit significant differences, decreasing from the middle to the corner point, with distances of approximately 0.8 at the quarter points and minimum distances of approximately 0.55 at the corner points.

关键词: wireless sensor network (WSN)     tunnel     monitoring     feasibility study    

Soft curvature sensors for measuring the rotational angles of mechanical fingers

Haixiao LIU, Li LI, Zhikang OUYANG, Wei SUN

《机械工程前沿(英文)》 2020年 第15卷 第4期   页码 610-621 doi: 10.1007/s11465-020-0596-0

摘要: The design, fabrication, and testing of soft sensors that measure elastomer curvature and mechanical finger bending are described in this study. The base of the soft sensors is polydimethylsiloxane (PDMS), which is a translucent elastomer. The main body of the soft sensors consists of three layers of silicone rubber plate, and the sensing element is a microchannel filled with gallium-indium-tin (Ga-In-Sn) alloy, which is embedded in the elastomer. First, the working principle of soft sensors is investigated, and their structure is designed. Second, the relationship between curvature and resistance is determined. Third, several sensors with different specifications are built in accordance with the structural design. Experiments show that the sensors exhibit high accuracy when the curvature changes within a certain range. Lastly, the soft sensors are applied to the measurement of mechanical finger bending. Experiments show that soft curvature sensors can effectively reflect mechanical finger bending and can be used to measure the bending of mechanical fingers with high sensitivity within a certain working range.

关键词: soft sensor     Ga-In-Sn alloy     strain sensing     curvature sensing     mechanical finger bending    

WEIS wheel speed real-time measuring method for VOSM

Mengyao PAN, Guixiong LIU, Xiaobin HONG, Tusheng LIN,

《机械工程前沿(英文)》 2010年 第5卷 第3期   页码 322-327 doi: 10.1007/s11465-010-0022-0

摘要: Wheel speed is one of the key parameters of vehicle operating attitude. To solve the problems in traditional wheel speed measuring methods, such as low measurement precision and the lack of real-time monitoring of the vehicle’s operating attitude, a wheel embedded intelligent sensors (WEIS) wheel speed measuring method for vehicle operating safety states monitoring (VOSM) is innovatively proposed. Radial acceleration signal is obtained through a WEIS module embedded in the hub. Using wavelet packet to implement wavelet de-noising for the non-stationary acceleration signals, and adopting short-time Fourier transform (STFT) algorithm to extract the signal characteristics, the wheel speed measurement can be achieved. The experimental result shows that under experimental conditions the speed measurement error is −2.05%, and the speed measuring response time is 0.45 s.

关键词: wheel embedded     intelligent sensing     wheel speed     monitoring    

水库水域生态系统温室气体排放测量技术

戴会超,李华,郑铁刚

《中国工程科学》 2010年 第12卷 第9期   页码 21-28

摘要:

基于国内外对全球温室气体排放监测研究的基础,总结并探讨了水库水域生态系统中温室气体排放通量常用测量分析技术的基本原理,对比分析了各种监测方法的适用性及优化措施,对我国形成系统的水库水域生态系统温室气体监测技术导则提供重要参考,为我国绿色水电和可持续发展水利水电建设提供重要的技术支撑。

关键词: 水库水域生态系统     温室气体     通量     测量技术    

A spectrometer for measuring particle size distributions in the range of 3 nm to 10 μm

Jieqiong LIU,Jingkun JIANG,Qiang ZHANG,Jianguo DENG,Jiming HAO

《环境科学与工程前沿(英文)》 2016年 第10卷 第1期   页码 63-72 doi: 10.1007/s11783-014-0754-x

摘要: A spectrometer combining electrical mobility sizing and aerodynamic sizing was developed to measure aerosol size distributions in the range of 3 nm to 10 μm. It includes three instruments which cover different size ranges (a nano scanning mobility particle sizer (NSMPS, 3 – 60 nm), a regular scanning mobility particle sizer (RSMPS, 40 – 700 nm), and an aerodynamic particle sizer (APS, 550 nm – 10 μm)). High voltage and sheath flow of the NSMPS and RSMPS were supplied using two home-built control boxes. A LabVIEW program was developed for spectrometer automatic operation. A linear inversion method was applied to correct particle multiple charging effects and to integrate data from the three instruments into a wide-range size distribution. Experiments were conducted to compare distributions in the overlap size ranges measured by three instruments. Good agreement between the NSMPS and RSMPS was achieved after correcting for the difference in counting efficiencies of the two particle counters. Aerodynamic size distributions reported by the APS were converted to mobility size distributions by applying an effective density method. Distributions measured by the RSMPS and APS were consistent in the overlap size range of 550 – 700 nm. A full spectrum in the size range of 3 nm to 10 μm was demonstrated by measuring aerosol generated using a mixture of different sized polystyrene latex spheres.

关键词: spectrometer     particle size distribution     electrical mobility     linear inversion     aerodynamic diameter    

盾构隧道长距离独头掘进的控制测量技术

许维青,韩福忠

《中国工程科学》 2010年 第12卷 第12期   页码 56-58

摘要:

北京地下直径线盾构独头掘进距离达5.2 km,因此隧道贯通精度控制难度大。通过测量精度分析,单纯通过导线测量已不能满足设计规定的贯通限差要求,施工中通过导线直接传递定向、洞内加测陀螺边、地上地下控制网紧密联系等辅助方法,提高了贯通横向误差的精度,达到了预期效果。

关键词: 盾构     长距离     独头掘进     控制测量    

微波快速测定镁质硅酸镍矿水分的应用研究

范兴祥,杨晶晶,黄铭,汪云华,李柏榆

《中国工程科学》 2007年 第9卷 第11期   页码 200-203

摘要:

利用微波技术快速测定镁质硅酸镍矿的水分,并对不同含水量的镁质硅酸镍矿对检测结果的影响 进行了分析和讨论;对微波检测装置、特性及其操作方法做了说明。

关键词: 微波     测定     镁质硅酸镍矿     水分    

高端测量仪器

谭久彬, Kenneth Thomas VictorGrattan

《工程(英文)》 2022年 第16卷 第9期   页码 1-2 doi: 10.1016/j.eng.2022.07.002

复合式叶片型面测量系统的误差分析与补偿

李兵,陈磊,丁建军,蒋庄德

《中国工程科学》 2013年 第15卷 第1期   页码 39-44

摘要:

针对具有复杂型面的叶片类零件检测中所面临的数字化测量问题,提出了一种复合式的测量原理与方法。分别采用接触式的电感原理和非接触式的激光三角原理测量叶片的叶根基准以及叶身型面,并基于此原理设计研制了叶片型面四坐标测量系统。研究中结合该系统的机械结构特征,对影响其测量精度的各项几何误差进行了系统的分析,并提出了基于激光干涉测量的误差提取与补偿方法。实验结果表明,应用提出的误差分析与补偿方法可有效获取叶片型面四坐标测量系统的几何误差并显著提高其测量精度。

关键词: 叶片型面     复合式测量原理     误差分析     误差补偿     激光干涉测量    

An autonomous miniature wheeled robot based on visual feedback control

CHEN Haichu

《机械工程前沿(英文)》 2007年 第2卷 第2期   页码 197-200 doi: 10.1007/s11465-007-0033-7

摘要: Using two micro-motors, a novel omni-direction miniature wheeled robot is designed on the basis of the bi-corner driving principle. The robot takes advantage of the Bluetooth technology to wirelessly transmit data at a short distance. Its position and omni-direction motion are precise. A Charge Coupled Device (CCD) camera is used for measuring and for visual navi gation. A control system is developed. The precision of the position is 0.5 mm, the resolution is about 0.05 mm, and the maximum velocity is about 52 mm/s. The visual navigation and control system allow the robot to navigate and track the target and to accomplish autonomous locomotion.

关键词: measuring     distance     autonomous locomotion     advantage     navigation    

Coordinate system applied to magnetic suspension project between Shanghai and Hangzhou

SHI Yimin, WANG Lihua, LUO Yan

《结构与土木工程前沿(英文)》 2008年 第2卷 第3期   页码 288-292 doi: 10.1007/s11709-008-0041-7

摘要: In order to satisfy the requirement for route location of a magnetic suspension project between Shanghai and Hangzhou, this paper proposes to adopt a new form of geodetic coordinate system, which is defined by meridians and parallel circles but with two coordinate parameters expressed by length. Not only the coordinate systems for route location along the whole line can be unified, but also the precision of lengths and angles obtained from simple formulas are very high and there are not any map projection distortions. This has been proven by calculation.

关键词: requirement     projection     calculation     Shanghai     precision    

A space solar cell bonding robot

FU Zhuang, ZHAO Yan-zheng, LIU Ren-qiang, DONG Zhi

《机械工程前沿(英文)》 2006年 第1卷 第3期   页码 360-363 doi: 10.1007/s11465-006-0027-x

摘要: A space solar cell bonding robot system which consists of a three-axis Cartesian coordinate s robot, coating device, bonding device, orientation plate, and control subsystem was studied. A method, which can control the thickness o

关键词: Cartesian coordinate     thickness     three-axis Cartesian     orientation     control subsystem    

标题 作者 时间 类型 操作

Research on physical shape preserving curve reconstruction

TANG Kelun, ZHANG Xiangwei, CHENG Siyuan, XIONG Hanwei, ZHANG Hong

期刊论文

New form of geodetic coordinate system taking two length quantity as coordinate parameters

Yimin SHI, Ziyang ZHU, Yeming FAN

期刊论文

Comparison of analytical procedures for measuring phosphorus content of animal manures in China

null

期刊论文

A feasibility study of the measuring accuracy and capability of wireless sensor networks in tunnel monitoring

Xiaojun LI, Zhong JI, Hehua ZHU, Chen GU

期刊论文

Soft curvature sensors for measuring the rotational angles of mechanical fingers

Haixiao LIU, Li LI, Zhikang OUYANG, Wei SUN

期刊论文

WEIS wheel speed real-time measuring method for VOSM

Mengyao PAN, Guixiong LIU, Xiaobin HONG, Tusheng LIN,

期刊论文

水库水域生态系统温室气体排放测量技术

戴会超,李华,郑铁刚

期刊论文

A spectrometer for measuring particle size distributions in the range of 3 nm to 10 μm

Jieqiong LIU,Jingkun JIANG,Qiang ZHANG,Jianguo DENG,Jiming HAO

期刊论文

盾构隧道长距离独头掘进的控制测量技术

许维青,韩福忠

期刊论文

微波快速测定镁质硅酸镍矿水分的应用研究

范兴祥,杨晶晶,黄铭,汪云华,李柏榆

期刊论文

高端测量仪器

谭久彬, Kenneth Thomas VictorGrattan

期刊论文

复合式叶片型面测量系统的误差分析与补偿

李兵,陈磊,丁建军,蒋庄德

期刊论文

An autonomous miniature wheeled robot based on visual feedback control

CHEN Haichu

期刊论文

Coordinate system applied to magnetic suspension project between Shanghai and Hangzhou

SHI Yimin, WANG Lihua, LUO Yan

期刊论文

A space solar cell bonding robot

FU Zhuang, ZHAO Yan-zheng, LIU Ren-qiang, DONG Zhi

期刊论文