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Fine machining processes are of great importance in automotive series production, e.g. the machining of valve guide and seat in the cylinder head of a combustion engine. In industrial manufacturing processes, disturbances are inevitable and provide a measure of uncertainty in each production step. Increasingly, the influence of such uncertainties is being evaluated using simulation models. In this paper, a modeling approach for simulation of multi-stage fine machining processes with step tools is presented and investigations regarding influence of uncertainty caused by disturbances are performed.

The Wonogiri Reservoir with 1.343 km2 catchment area has a major problem of sedimentation. To overcome this issue, a new spillway has been built and closure dike is being constructed to localize sediment inflow from the Keduang watershed. Study on the effect of the closure and overflow dike on the reservoir operation in flood period is necessary to evaluate the performance of flood control related to the flood risk in the downstream area of the reservoir. For this purpose, the reservoir routing simulation model was developed under two condition, namely old condition and new condition with the new spillway and closure dike. The reservoir routing simulation was conducted for three inflow hydrographs of 60 and 500 years return period, and probable maximum flood (PMF). The results show that the presence of closure dike causes the peak outflow discharge increases to 1.45%, 75.18% and 56.28% for inflow hydrograph of 60 years, 500 years return period and PMF, respectively. Furthermore, the maximum water level also increases by 0.3 m, 1.9 m and 0.9 m for those three new design floods respectively. In order to reduce the dam overtopping failure chance of the 500 years return period flood, it is recommended to operate full opening of the new spillway gate when the water level reaches elevation +135.6 m MSL.

Investigation of residual stresses in an infrastructure is important due to the reason of safety. One of the most important problems is non-destructive testing of residual stresses particularly in welded constructions. A quite lot of technologies are used to solve this problem. Ultrasonic testing is based on the dependence of the velocity of ultrasonic waves on the stress value within a material under study. This technology is robust, operative and can be used in field conditions. The main problem is to measure the velocity of ultrasonic waves with high precision at a short trace. The proposed technique of the Contact Laser-Ultrasonic Evaluation (CLUE) is used in our work to overcome this difficulty. The variation of the results of the measurement of the ultrasonic wave velocity using CLUE does not exceed 0.05% and provides the threshold of the detection of the residual stress in steel at the level of 2-3 MPa. Basics of CLUE and some experimental cases of the study of the uniaxial stress in compressed and tensioned rail steel specimens are described. The advantages and disadvantages of CLUE for the stress measurement are discussed.

This paper presents a numerical algorithm technique to detect cracks propagated in concrete beams based on the frequency response curve of the beam determined from vibration testing. Impact tests on simply supported reinforced concrete beams were conducted to measure vibration on the beam. The ICATS software was carried out to capture the Frequency Response Functions (FRFs) data at each load step. Utilizing the FRFs data, a numerical algorithm based on finite different methods was performed to compute the different FRFs between undamage and damage beams based on the mode shape curvature square (MSCS) method. The numerical damage location was defined by subtracting the MSCS undamage to damage of beams. Therefore, the accurate damage location was identified by comparing the numerical and observed experimental results.

This paper is to explore the measure of isotropy applied to a 2-DOF revolute spherical serial manipulator. A revolute spherical serial manipulator means that the directions of rotation of the manipulator are intersecting. This manipulator arm will be used for carrying microscope camera as part of the 2-hand master-slave operation with force reflection system for miniature task operation in order to enhance view of vision. The data of the dexterity measure are collected from the computer simulation based on invert kinematics and Jacobian of the manipulator. The results revealed that the design solution of the manipulator has high measure of isotropy for prescribe paths. This result is to confirm that the manipulator can move with in the design workspace smoothly.

This article is focused on the problematics of high-pressure fuel injectors of Common Rail system which are inside of high pressure environment. Those injectors are able to measure cycle's amount of fuels and visualization of fuel ray disintegration during outflow into high pressure environment. Article is primarily focused into a construction of pressure testing chamber which will be functional extension for high pressure systems testing device. Monitoring of measured parameters will have positive influence during designing of constructing changes on the injection unit.

In this work, identification of rebar radius for a single steel reinforcement buried in a concrete member was investigated. A method based on electromagnetic penetrating radar was proposed. The principle of this method consists of working with adequate high frequency antennas that emit short pulses and measure the reflected echoes from the discontinuities present inside the medium. Image post-processing of the obtained B-scan radargrams enabled to extract essential information which has facilitated the derivation of a correlation formula to estimate the rebar radius. Predictions made by this formula were found to achieve better accuracy than previously known methods.

This article discusses the use of accelerometers to measure the angle of rotation of the kinematic pairs. The main problems of accelerometer methods and justified phasemetric method of forming the differential signal transducer. The application phase metric method accelerometeric measuring the angle of rotation of the kinematic pair eliminates the multiplicative error at the preliminary stage of the measurement.

This paper integrated a laser triangulation probe with a two-dimensional image measurement system to measure the height of an object using the auto-focusing method. In the laser triangulation probe, the laser diode was used as the light source and one-dimensional position sensitive detector was adopted to receive the position of the laser spots to detect the height. The laser triangulation probe was used for small height measurement and the auto-focusing method was used for large height measurement. Two standard gauges with thicknesses of 8mm and 8.5mm were used to verify our proposed method. With height difference of 500μm, the experiment results showed the measuring error was within ±3μm and standard deviation was about 0.1μm.

In this paper, research on a testing method of indentation test proposed by F M Haggag is discussed first, and the experimental testing research on metallic material properties with strain aging is carried out and discussed using indentation test. The authors proposed to use indentation test to measure the properties of metallic materials with strain aging embrittlement based on experimental verification. And it provides a possibility to measure the properties of metallic materials with strain aging using nondestructive testing method.

This paper presents a 20 Hz to 200K Hz alternating current (AC) and direct current (DC) analog-to-digital converter (ADC). The strange to minimize the zero crossing noise adopts hysteresis comparison technique. Multi-slope integral technique is also employed to enhance measurement accuracy. Furthermore, an algorism is designed to eliminate measure error. The prototype ADC achieves millivolt precision.

The eddy current sensor can be used to measure the displacement. It is widely used in petrifaction, electric power, mechanism. The eddy current sensor has fast dynamic response, non-contact measurement, and better adaptability characters. The accuracy of eddy current sensor often is influenced by the environment temperature. The environment temperature effect is analyzed and put forward to a method to compensate to enhance the accuracy.

Black-start is an effective measure to restore the power system when blackout occurs. An appropriate black-start scheme may not only speed up system restoration, reduce outage losses, but also have important significance to deal with emergencies. In this paper, a method to design black-start scheme for a combined system in Taizhou regional grid is presented. The feasibility and efficiency of designing black-start scheme is significantly improved, based on comprehensive consideration of Taizhou regional situation and the real-time status of hydropower, wind power, energy storage and circuits. The simulation results show that the new method is valid.

This paper researches on the non-contact online detection of concentricity error, which mainly focus on the structural principle of the measurement system and the concentricity error evaluation methods. The paper using the method of projection, converting the three-dimensional model to a two-dimensional model and evaluating coaxially error. And it is validated by the simulation of MATLAB. In theory, the proposed measurement system can measure geometric tolerance, including coaxially error, cylindricity error, circularity error, etc.

In this paper ,the method of the fluorescence lifetime (FL) in fluorescence optical fiber temperature sensor is used to measure the temperature. During the fluorescence information processing , because of existence of the system noise interference, measurement reliability of fluorescence lifetime has been greatly affected, thereby reducing the temperature measurement precision. This paper presents an improved wavelet threshold de-noising method to signal processing, which improves the signal-to-noise ratio and increases the measurement of fluorescence lifetime precision, reduce the error of temperature measurements at the same time. The experimental results demonstrate that this method is effective.

In order to measure capture performance of the seeker in the typical terminal guidance scene under HPM damage effect, the paper proposes a new method to model the dynamic capture state in different ballistic position. The proposed missile-target geometry count can be used to process multiple data generated in multiple Monte Carlo simulations under the same scene, which facilitates capture performance comparative analysis between different scenes. Simulations validate proposed counting measure, so that it can be applied for measuring the performance of missile capture.

In the micro-climate cloth researching, we usually need to accurate measuring the body temperature, in this paper we choose the constant-voltage temperature measuring system based on the NTC thermistor to measure the temperature. Because the resistance of the thermistor and the temperature is not linear, so this will cause the output of the measurement circuit is not linear. In actual measurement we usually require the output of the circuit varies linearly in the required range. This paper mainly research the linearization problem of the NTC thermistor bridge circuit in the required temperature range.

A new method to predict ocean wave spectra based on X-band radar is proposed. X-band wave-measuring radar is a new powerful tool to monitor ocean wave, and is the only method that can be used to measure wave spectra onboard and in real-time. This makes wave spectra prediction possible. The real ocean wave is a non-linear process. Through screening time series prediction method based on wavelet neural network is chosen looking at its strong ability on dealing with non-linear problems. The experimental result indicates that this method is of high precision.

This article describes a method to measure the refraction index of transparent material by combining the characteristics of transparent material with 2D digital image correlation. The method established the relationship between refraction index and in-plane displacement of speckles using the refraction principle. In-plane displacement can be calculated by the 2D digital image correlation directly. Refractive index of PMMA were obtained by speckle patterns which were recorded by single camera. Results showed that the calculation is very close to the existing PMMA material refractive index value that proved the feasibility and the effectiveness of the method. Of course, this method also can be used to calculate the thickness of the transparent material to widen its using fields.

Traditional tooling for aircraft skin will produce a large clamping deformation of the inadequacies in the assembly process, designed a vacuum suction cup flexible assembly tooling, that tooling using vacuum suction force to clamp the workpiece in the assembly process, greatly reduces the amount of deformation of the workpiece. In order to accurately grasp the new tooling excellent performance in terms of adsorption deformation, through the establishment of a laser measuring device test platform, we conducted a large number of studies of vacuum adsorption deformation experiment on different thickness of the workpiece,has been obtained the workpiece adsorption deformation rate range under the flexible tooling system, as well workpiece thickness, sucker adsorption, the number of anchor effect on the adsorption deformation rate of the workpiece, and verify the reasonableness of the flexible assembly tooling.

In the actual operation by crane operator, there will appear situation that operator cannot make timely judgment on distance between crane and adjacent obstacle and cause collision accident. For this problem, this paper establishes anti-collision system on distance measurement focuses on ARM 11, on the basis based on machine vision and image procession, it considers effect of corresponding point match and extraction deviation of single characteristics point on measurement result, adopts one kind of method of distance measurement by monocular vision based on single characteristic point. The test result indicates that this system can effectively measure distance with obstacle, it has accurate measurement, high reliability and it can meet real-time requirement.

This paper discusses a kind of total wave force sensor, which includes the wave total force sensor principle design,the total force sensor structure design, measuring circuit design. And analyzes the relation between strain and the structure parameters at the position of strain gauge, the coordination between measuring circuit and structure. A more reasonable wave total force sensor structure has been synthetically selected. Cooperated with reasonable strain measuring circuit, the total wave force sensor has been designed, which is used to measure 3-D wave force and has promoted the wave total force sensor innovation and development.

Magnetic rotary encoder can be used to detect the rotor position of PMSM, in order to realize vector control of PMSM. An initial positioning method on magnetic rotary encoder based on open loop control system was presented to calculate absolute difference of average through setting Rotor position angle on multi point.Experimental results show that the method was simple and suitable to measure rotor angle exactly and easily.

Array induction tools can be used to measure the resistivities of thin beds with 1ft or 2ft thickness in theory. The measurements were affected by formation thickness and shoulder resistivity.The array of 1ft resolution has good vertical recognition ability. For thick beds, both 1ft and 2ft resolution matching data tent to the same and all apparent resistivities have less variation with bed thicknessH. The influence of shoulder resistivity on AIT measurements decreased with the increasing of formation thickness. The greater is the difference between shoulder resistivity and formation resistivity, the poorer is the vertical resolution.

In recent years, the cultivation of innovative ability of master of engineering has become a heated topic. This article first clarifies some concepts and characteristics of innovation ability of Master of Engineering and analyzes main issues in training innovative ability. Then evaluate the traditional Single Triple Helix Model in aspects of its origin and content, its advantages and disadvantages. After pointing out the hysterics of the old model, this article illustrates how to construct a new double triple helix model and then proposes some measure to secure its operation.

The interface blunt-prosthesis from blunt-prosthesis-rod complex is the subject of stress and friction due to forces that act in the walking stage. The dermal wounds and patient's discomfort sensation that can appear can be alleviated or predicted by analyzing the stump’s pressure map taking into account tribological aspects. There are many studied related to transtibial prosthesis but studies that analyze the transfemoral prosthesis are relative rare. A analyze of pressure in blunt-prosthesis complex for transfemoral sub-ischeal prosthesis is proposed during a complete gait cycle.The experiments used three types of liners and a standard type of socket. The areas that are subject of maximum stress and friction are identified as the value of forces of moments that act n stump during a gait cycle. An integral measure and functional ones are proposed to evaluate for influence of each factor that can contribute to optimization of prosthesis and an empirical formulas that connect these measure for prediction is suggested. Theoretical approaches are presented along with experimental results and further research directions.

This paper introduces a new correction method for laser scanner system. Based on image recognition, the laser marking result which includes a crossed matrix is grabbed as matching pattern. A algorithm is presented to locate all crosses and measure their positions , and a correction data is generated automatically for laser scanner system. This method makes the correcting process be much faster and more accurate than conventional manual measurement way.

The method to measure the branching fraction of decayed from in experiment has been studied. Based on the data sample collected on the BEPCII and the optimized criteria for event selection, the result can be obtained.

Infrared imaging simulation is important in national defense, military affairs, aviation and aerospace etc. A method of infrared imaging simulation is proposed based on Vega sensors, in this paper. The 3D model of air target with a visible texture was built with the software Creator. Then infrared texture was mapped to get by the tool TMM and atmosphere conditions were modeled in MAT and infrared image was simulated using Vega sensors. Finally the emulational infrared image is corrected using infrared imaging instrument and the measure instrument of infrared radiation on the surface of objects based on the above results.The experimental results show the method of infrared imaging simulation is effective and valuable in engineering application.

The flow in centrifugal fan and 90° bend pipe was simulated numerically by the RNG k-turbulent model in software Fluent, and obtained the distribution diagram of the pressure and velocity. From the distribution diagram of the pressure and velocity, for measurement, three measurement points must be chosen, and two of them should be closed to the wall of pipe. However, in order to insure the measure accuracy, five or six measure points should be chosen. In addition, the velocity distribution of pipe bending reaches well-distibuted at the 1000 mm away from pipe exports. That is fluid flowing after through the flow field of bending section tends to uniform soon, so for the greater curvature bend pipe, measurement is more convenient.

Using the finite element software “ANSYS” to establish the three-dimensional coupled model in magnetic field and temperature field during the process of transverse flux induction heating of ring-shaped heater and Square-shaped sheet steel, this paper studies the distribution laws of the magnetic and temperature fields in the induction heating process. Through studies, the calculations show: 1) The distribution of the magnetic fields and eddy cavities in the sheet workpiece is in the shape of ring; has close ties with the shapes of the coils; 2) The intensities of the coils’ magnetic field and eddy cavities reach the strongest in the projection of sheet metal, and the temperature in the projection part also rises the fastest. For the purpose of verification, the induction heating experimental plat is established to measure the changes of temperatures of numerous points in the plat and to compare the changes with the calculations. Via the comparison between the simulation results and the experimental measurements, the results of numerical simulation are confirmed reliable, and can be used as the theory and the experimental basis for the design of the induction heating system.

Cutting force is one of important parameters for manufacturing processes. The traditional dynamometer is limited by size, machining environments, and so on. This paper introduces a new constantan thin film sensor which embedded on the holder of external turning tool to measure cutting force. The relationship between force and output voltage are deduced from theory. By using the finite element software, the analyses on induction and linearity capability of thin film sensor are simulated, and the influences of the location and thickness of film on the output voltage are analyzed. The results show that the linearity of input and output is good and the deviation between the calculated value and simulation results is identical. As the result, the constantan thin film sensor unit can be used to measure the cutting forces.

Steam pressure and resonant frequency of microwave cavity are important measure parameters of microwave wetness measurement system. The measuring precision of pressure and frequency directly affect the accuracy of wetness measurement. This paper takes different pressure and wetness of steam as example to analyze the parameter uncertainty of measurement relationship and deduces standard uncertainty of wetness measurement. The system comprehensive uncertainty is identified, when the parameters measurement, cavity heat expansion, sampling error, sedimentary water film and so on are considered. The result shows that the system uncertainty is less than 0.004%. The system uncertainty introduced by pressure measurement is small and can be neglected, but the system uncertainty from frequency measurement has a great effect. The precisely measurement of resonance frequency is key to ensure the accuracy of the system.

As a high precision attitude measuring instrument in arc-second level, star sensor has become a necessary component for satellites, spacecraft and space station. However, star sensor misalignment angle can reach the arc-minute level and reduce the accuracy of the star sensor’s output severely. Since it’s difficult to measure the initial alignment error precisely on the ground, research applicable to star sensor misalignment angle calibration technique is necessary. To make the system get a high precision attitude control, a GPS-assisted Kalman filter modeling of the system was carried out. Finally, the misalignment angle from the board axes to the star sensor axes can be estimated by employing the derived relationship. The mathematical simulation results show the effectiveness of the calibration algorithm.

The external turbine can be used on underwater high-speed moving body to measure its own velocity. By establishing the rotating turbine dynamic equations and using UDF programming for secondary development on fluent software, the three-dimensional dynamic simulation of water speed measurement turbine model was achieved. Using this model, under the complex flow environment like cavitation and small attack angle, the dynamics simulation was performed and the results was analyzed to get the turbine movement characteristics. Simulation results show that the simulation model can reflect the variation in characteristics of the turbine caused by the small attack angle at cavitation situation.

In multiattribute decision making, it is critical to indentify the importance degree of attributes before the overall assessment of the alternatives. In this paper, we give a measurement of importance degree of attributes based on knowledge discovery in the decision information system, which satisfies the conditions of fuzzy measure. Further, we construct an evaluation model combined Choquet integral with the importance degree measure. The case study illustrates the validity and the effectiveness of the method.

In this work, we investigate the measure of isotropy of a manipulator based on its Jacobian matrix. Our manipulator is an exoskeleton arm robot for human physical therapy. An exoskeleton arm robot is wearable robot with joints and links corresponding to those of the human body. Our goal is to derive dexterity measures called the measure of isotropy which can be used for both design and real-time control of a manipulator. Generally, a dexterity measure must be independent of the scale of a manipulator for design and must be expressed analytically so that it can be used for real-time control. Of course, every dexterity measure must bear a physical meaning.

Sensor systems are an essential part of automated equipment. They are even more important in machines that come in contact with people, because they have a significant impact on safety. This paper describes the design of active feedback for rehabilitation device driven by pneumatic artificial muscles. Here are presented three methods for measuring the load of the robot. The first is a system composed of Force Sensitive Resistors (FSR) placed in the handle of the device. Two other methods are intended to measure the load of the actuator composed of artificial muscles. The principle of one method is to measure the difference in filling pressures of the muscles, second is based on strain measurement in the drive cables. The paper describes advantages and disadvantages of using each of these methods in a rehabilitation device.

An Approach that measuring static radial and axial runouts around rotational centre of spindle for cylindrical mills on milling machine was presented, its possible errors coming from imprecise location of gauge were theoretically analyzed. Milling force measuring experiments with variable feeds and cutting depths in low spindle speed was done to estimate the static runouts, these estimated values then were used to test the precision of measured values with this approach. Both results of theoretical analysis and experimental test showed that the relative errors of this measuring approach were small. This approach is to measure the runouts of installed mills, and its measured value is rather precise, its operation is simple, and it needs no special gauge. This approach can be used in study on force of cylindrical mills.

In recently years, in order to exactly judge artillery capability, we should measure important parts of distortion. In this article, we research and design a non-contact three –dimension measure system of artillery parts distortion, and it can get exactly measure results.

Several conventional steady-state measuring methods of material coefficient of thermal conductivity was systemically compared and discussed. The limitations and shortcomings of the infinite flat layer method, the infinitely long cylinder method and the concentric spherical shell layer method were pointed out. A new method for measuring the material coefficient of thermal conductivity, standard sample method, was proposed. The measure principle, the preparation of standard sample, the measure process and the obtainment of the result were presented. The advantages and applicability of the standard sample method to measure coefficient of thermal conductivity were evaluated.

Deformation of expansive soil subgrade depends on moisture content. Anti-seepage measure of unsaturated expansive soil was carried out using ABAQUS as for the influence of atmosphere. The results show that there is large change in water content using anti-seepage measure measure. After using anti-seepage measure, range of water content decreases. At the same time, range of water content value obviously decreases with the increase of the depth of seepage control. Therefore, damage of pavement caused the deformation can decrease by seepage control measure. The results could be used for engineering design and numerical calculation.

Due to the quality of all aspects of the human body differ greatly, collecting attitude parameters,electronic scales can not achieve the precision requirements. Therefore, how to ensure a large range torque measurement accuracy becomes the core of a recognition system of dimensional distribution of body weight. In this paper, based on the original measure will convert measuring force to measure the distance , redesigning the said bed to improve test accuracy.

When we use the laser auto collimation theodolite to measure the azimuth error angle of air target, the strong noise background reduces the spot imaging quality and seriously influences the measuring angle ability of the theodolite. In order to solve the problem, a photoelectric detection system used to detect the weak signal is designed based the correlation detection principle and the principle of correlation detection technology is introduced. We use Simulink software presenting a simulation to the detection system and do a feasibility analysis. Finally, it's proved that the photoelectric detection system could suppress the strong noise background, improve the SNR greatly and detect the weak signal effectively. © (2014) Trans Tech Publications, Switzerland.

The supporting structure in foundation pit is very important in civil engineering and is used to support the whole foundation pit. Its diaplacement is directly related to the safety of buildings. White light digital image analysis in frequency domain has the advantages of whole-field, non-contact measurement and the simple measuring system and can obtain displacements by frequency domination correlation arithmetic. In this paper, the method was introduced to measure the displacements of supporting structure. The experimental results show the usability of the method for supporting structure in foundation pit.

This paper presents a novel sensory system for monitoring situations of riding bicycle. The proposed system can be used to measure and save in real-time not only the motion of bicycle rider but also the situation near the vehicle. Multiple inertial sensors being attached to human body are employed to measure the motion of the rider. Two laser scanners installed in the front of the bicycle and two cameras of wide view angle were used to detect the environmental change including pedestrians and static/dynamic objects. The system configuration was designed for the synchronization of multiple sensors according to the position information of the vehicle. Particularly, the human motion of riding bicycle is captured with the system and analyzed with the measurement data in this paper.

IPMC (Ion-exchange polymer metal composite) is a kind of novel artificial intelligent materials. It has a lot of good properties, such as light weight, good flexibility, easily cut in any size and shape, and can be used as both an actuator and sensor. A micro-force sensor based on the theory model of cantilever beam structure of IPMC is built up, which is applied to measure probe force during the micro operations under the environment of the cell injection.

During basketball sport, the movement of a joint is quite complex. And if move fast, it is difficult to constrain by fix algorithm the subtle angle changes between joints. Traditional sports vision modeling method is unable to describe the moving changes of the small areas which causes the unsatisfactory measuring effect of subtle posture in motion. This paper proposes a measurement method for three-dimensional motion posture of basketball athletes. It converts the constrained optimization problem for motion parameters as a nonlinear minimization problem by optimizing human motion parameters; uses L-M motion constraints parameter to provide fast convergent regularization method, in order to seek motion and structural parameters matrix of non-rigid basketball sport and complete three-dimensional measurement for motion parameters. The simulation results show that the method can accurately measure the 3D movement parameters of the athletes.

This design has proposed a method which uses the Hypogynous Computer and ARM together to get a high speed temperature field display.It displays multi re-biulded severed two dimension section by takig image superier performance of WinCE 6.0 operation system as the subject.It has introduced a design idea with modular processes, and it provides a reference for the miniaturization intelligent instrument which it's measure subject is field.

Vibrating wire sensor signal acquisition system is widely used in the fields of water conservancy dam, slope, construction, mining and so on to measure osmotic pressure, soil pressure, strain and other physical quantities. This paper studies the single coil vibrating wire sensor signal acquisition system,which uses the STM32F103 core processor generating a low-voltage feedback PWM signal to excite vibrating wire with scanning frequency, after signal amplification, filtering and signal normalization through the frequency measurement module, and ultimately achieve frequency measurement. The system can improve the traditional vibrating wire acquisition instrument, so as to achieve fast and efficient and reliable long-lasting measurement. According to some simulation and designed circuit, the measured data and diagram can verify the feasibility of the method.