bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Distribution Performance of a New Oil-Air Distributor in Oil-Air Lubrication System
Authors: Sun Qi Guo , Zhou Zheng Hui , Lv Hong Bo , Wang Yue Fei
Published: February 2014

The fluid domain model of a new oil-air distributor in oil-air lubrication system is built and the phase distribution of oil and air two-phase flow on distribution interface is simulated based on the CFD model in Fluent, the mass flow rate of oil and air are collected from three different cross sections when the structures of oil-air guidance slot are designed as a plane, sphere and cone shape respectively, then the influence of oil-air guidance slot structure on the performance of distributor is analyzed in the oil-air lubrication system in this paper. The results show that the spherical surface and conical surface of oil-air guidance slot can improve the uniformity and stability of the oil and air two-phase flow distribution, promote the flow pattern to form a continuous annular oil film. Among these three structures of oil-air guidance slot, we also find that the distribution performance of conical surface is the best.
The Characteristics of the Annular Flow through the Sudden-Expansion Pipe of the Oil-Air Lubrication System
Authors: Sun Qi Guo , Wang Xiong Shi , Wang Ying , Li Zhi Hong
Published: February 2014

The characteristics of the sudden-expansion pipe in oil-air lubrication system have been analyzed based on Fluent. The results show that the pressure and oil film mutate when the annular flow through the sudden-expansion pipe and the suddenly change of position of pressure and film is not affected by the inlet air velocity, however, the strength of pressure and film is in direct ratio with the inlet air velocity. The film of oil-air annular flow in the pipeline before the suddenly expanding part is well-distributed, but the distribution after that is widely affected by the air velocity and the pipe diameter, and furthermore the larger air velocity and pipe diameter increase the degree of dispersion of the annular flow film.
Design of Hydraulic Station of Crawler Hydraulic Drilling Rig
Authors: Liu Zhi , Fang Peng , Wu Di , Li Dong
Published: February 2014

This article describes the design process of pumping stations of crawler full hydraulic drilling rig. The principle of full hydraulic drilling rig pumping station,scheme selection, hydraulic components selection and structural design of the tank were presented. The system used double loops in which some advanced hydraulic components and control technique were adopt.
Simulation Research on the Basic Performance of a Single Piston Hydraulic Free-Piston Engine
Authors: Li Shi Yu , Yuan Zhao Cheng , Ma Jia Yi , Zhu Qing
Published: February 2014

Hydraulic free-piston engine is a compact machine which is composed of a conventional engine and a hydraulic pump. Compared to the conventional technology, the free piston engine has many potential advantages. In this paper, a simulation model for a single piston hydraulic free-piston engine (SPHFPE) is described, and the differences in motion characteristics between the free-piston engine and the conventional engine are presented. And varying piston mass and starting pressures have an impact on the motion characteristics of the free-piston engine.
Benefit Estimation of Automatic Braking System Based on Real-World Pedestrian Accidents
Authors: Kong Chun Yu , Gao Xiao Bao , Nie Jin , Mo Fu Hao , Yang Ji Kuang
Published: February 2014

The aim of the current study was to assess effectiveness of automatic braking system quantitatively using real pedestrian accident data selected from IVAC database. Based on the IVAC pedestrian accident scenarios, vehicle and pedestrian trajectories, and other information, the relative position of vehicles and pedestrians were estimated one second (0.5 second) prior to the actual crash. According to the pedestrian fatal (AIS3+) risk and compared with the real pedestrian casualty risk, the benefit of the automatic braking system was calculated. About 86.8% (82.3%) reduction in pedestrian fatal (AIS3+) injury at a field of view of 60°.
Modeling, Validation and Optimization of Car Side Impact
Authors: Xing Yan Yun , Yu Bo , Yang Fang Qun
Published: February 2014

In this paper, a passenger cars side impact CAE model was built with LS-DYNA software according to Chinese New Car Assessment Program (C-NCAP), the model was correlated very well with the test based on the data of B pillar intrusion velocity and the deformation of B-pillar and door intrusion. In order to improve the performance for side impact, the optimization proposal was provided after analyzing the results. It is showed that the side impact performance of the car was enhanced significantly after the optimization implemented.
Study on the Relationships between the Optical Printing Density Based on the Offset Overprint Trapping and Ink Film Thickness
Authors: Yang Yong Gang , Gao Qiao Zhuo
Published: February 2014

The research finds out some existing certain regularity, and further revises the formulaD=D(1-e-ml). The formula means the relationship between ink thickness and ink in density. By using the formal of one-color ink thickness and ink density, the second density that correspond the first major density is transferred to the equal thickness. Then they are added together. According to the formula the real ink density is calculate. Then use the above formula to work out ink thickness. In this way, overprint densities come out, and make contrast with the actual measure data, so the new model formula is built up. The result shows that the average error between the overprint density calculated by ink thickness and the actual measure data is about 0.07. However, the average error between the calculated density using the simple adding method and the actual measure data is about 0.5, so this method is practical and more accurate.
An Auto Flip Delivery Mechanism of the Paper Laminating Machine
Authors: Xin Jian Feng , Cai Ji Fei , Zhu Ning Kuan
Published: February 2014

In order to solve the problem that the paper will be wrapped and distorted after being laminated by the paper laminating machine, an auto flip delivery mechanism of the paper laminating machine is designed. A set of flip mechanism is installed in the delivery part of the paper laminating machine for placing the small paper stacks right side up or side down, which effectively prevents the laminated paper from being wrapped and distorted. Comparing with manual delivery, it saves labor, reduces the number of employers and also reduces the cost of the enterprises. The effectiveness of the mechanism has been verified in its actual application.
Dynamic Characteristics and Load Coefficient Analysis of Involute Spline Couplings
Authors: Xue Xiang Zhen , Wang San Min
Published: February 2014

As one of the important components of aviation and space transmission systems, dynamic characteristics of involute spline couplings influence its lifetime and reliability seriously. Here, taking the backlash of spline joint into account, considering the meshing stiffness varying with the teeth engaged, established the dynamic model with varying stiffness and dynamic equations, and calculated the number of actual meshing teeth and comprehensive meshing stiffness while bearing the varying torque, then, solved dynamic equations using the fourth order Runge - Kutta method, finally, get the teeth meshing number is 23,and the maximum dynamic load coefficient gets smaller from 1.19 to1.15 with the decrease of . This provides a numerical basis for wear`s studying and lifetime`s forecasting of involute spline coupling.
Vibration and Noise Damping Treatment for an Excavator Cab
Authors: Mi Yong Zhen , Zhou Yi Qi , Wang Li
Published: February 2014

Acceleration signals at the mounts of an excavator cab are collected and analyzed, on the basis of which causes of peak values in the sound pressure level (SPL) at the drivers right ear (DRE) are discussed. A damping material layer made up of chlorobutyl rubber is arranged to the cabs panels by simulations according to results of panel acoustical contribution analysis, which indicates a great decline of the SPL peak values.
Research on Topology Optimization Design Based on Finite Unit Analysis of the Flywheel Hub
Authors: He Pi Yan , Yang Jia
Published: February 2014

Topology optimization design is to ensure the normal functioning of the machine, remove the invalid element structure makes the best structure to maintain the structure and keep the stress or strain level close to the same in each part of the security configuration, the pursuit of the best efficiency, lightest weight , smallest, or the longest service life and so on. Traditional structural optimization design one or several parameters set as the primary determination. This method only to the extent required. With the development and analysis of the efficiency of the computer, we have introduced in the design of finite element analysis. This article uses the basic evolutionary structural optimization method In this paper, load the hub topology optimization analysis of different groups.
Effect of Piston Motion on Combustion of CNG Free Piston Engine (FPE)
Authors: Yin Ning Xia , Xu Zhao Ping , Chang Si Qin , Lin Ji Ming
Published: February 2014

CNG is thought to be one of the most promising alternatives to traditional fuels. The multi-fuel ability is another characteristic of the FPE. The piston motion can be controlled to have beneficial effects on the engine performance. This article investigates the effect of piston motion on combustion of four-stroke CNG FPE using a multidimensional simulation model. It is found that the high piston acceleration and velocity at top dead center increases expansion ratio and fasting combustion, reduces the heat transfer losses and decreased NOx emissions formation. At the same time, the turbulent kinetic energy of the gas during the combustion process is added.
Simulation of Crossing Threaded Planetary Roller Screw Engagement
Authors: Liu Yan Qiang , Wang Jian Shen
Published: February 2014

This article described the structure and movement principle of planetary roller screw; established the equation of screw thread surface and roller surface, solved the meshing points of crossing thread engagement using numerical methods, while the screw and roller meshing at pitch diameter; studied meshing relationship between screw and roller comparing the distribution of simulated meshing point under various design parameters. The conclusion provides a theoretical basis for choosing parameters of planetary roller screw.
Finite Element Application of Gear Tooth Analysis
Authors: Balambica V. , Prabhu T. Jayachandra , Babu R. Venkatesh
Published: February 2014

Gears play an important role in every aspect of power and motion of transmission from historical period to modern day period . Due to this , gear design has become a complicated art.A considerable amount of research has been carried out to determine the amount of dynamic gear tooth loads acting.The findings of the dynamic load between the gear teeth results in difficulty for the designer.In this paper, an effort has been made to formulate a simple design procedure for calculating the dynamic load .Earlier the stiffness characteristics and deformation of the gear tooth were studied to predict the dynamic load acting. This was developed with the tooth assumed as a short cantilever.Whereas in reality, an involute profile exists in a spur gear tooth.Based on this reality, work has been done to model the exact profile of the tooth.Later ,the stiffness characteristics were carefully analysed and an improvement was thus made. It was proved that FEA is one such technique that can be used for predicting dynamic loads acting on a gear tooth.
Research of Marine Simulator Cables' Mathematical Models
Authors: Liu Xin , Ren Wei , Zhang Qiang , Zhang Shu Hao
Published: February 2014

As ships gradually getting larger, more special, tug assisted operation of the ship in and out of Port , berthing and unberthing becomes increasingly prominent, Tug-related training and safety assessment is increasingly important, increasing the tug unit for marine simulator is urgent.In tug unit, the cable is an important part, to establish the mathematical model of cable is key. Mooring strain satisfy Hooke's law, using the catenary equation and Hooke's Law deduces mooring unstressed length formula, according to the Department to calculate the cable unstressed length and the corresponding relations of the actual length of the mooring to calculate the tension of the mooring; Otherwise, ignoring the weight of the mooring by mooring strain curve fitting polynomial to calculate the tension of the mooring, and calculated the level of tension and vertical tension of the mooring. calculating example to verify the correctness and practicability of the model.
Fractal Approach to Bubble Rising Dynamics in Non-Newtonian Fluids
Authors: Fan Wen Yuan , Yin Xiao Hong
Published: February 2014

The Laser Doppler anemometry was employed to determine quantitatively the liquid velocity induced by the successive rising of single bubble in non-Newtonian carboxymethylcellulose (CMC) aqueous solutions under various experimental conditions of mass concentration solutions, measures heights and gas flow rate. The features of liquid motion in the region of bubble rising channel were investigated by analysis the liquid velocity pulsation using fractal theory. The results show that the liquid motion in the channel zone of bubble rise has a special feature of double fraction, and shows strong positive persistence characteristics for a small delay, but the positive persistence characteristics begins to reduce obviously with the increase of the delay, and even presents the anti-persistence for some measured points.
Extraction Shafting Oscillation Characteristic of Hydro Turbine Generating Sets Based on Prony Algorithm
Authors: Wu Zhe , Zeng Yun , Zeng Yan Yan , Yu Shi Ge
Published: February 2014

Hydro turbine generating sets vibration is an important factor affecting the safe operation of hydropower stations. The research on the vibration characteristics is basic for the unit structure design, control design and hydropower station powerhouse structure optimization design. Based on built transient model of the hydropower turbine generating sets shafting, this paper constructed the whole hydropower turbine generating sets operating system by combine the hydro turbine, the generator object model, the governor and the excitation controller. Using numerical simulation method to obtained the shafting vibration data under different operating conditions. And then used Prony algorithm to extract the oscillation characteristics of amplitude, frequency, attenuation factor and phase angle from the vibration signal of hydro turbine generating sets shafting parameters. The simulation results show that the proposed method is effective.
Finite Element Analysis of Static and Dynamic Characteristics of High-Speed Horizontal Machining Center Bed
Authors: Wang Peng , Zuo Yan Rui , Ren Li Na , Song Dong Dong
Published: February 2014

Based on the theory of finite element and modal analysis theory, analysis of static and dynamic characteristics of the lathe bed has been done. The static displacement contours and mode natural frequency and displacement contours have been given to realize the structure optimization of lathe bed of high-speed horizontal machining center. It is shown that the bed has good static stiffness and natural frequency and the deformation of lathe bed mainly occurred in the tray conversion mechanism and the cutter location. The deformation of processing work area is small and has certain light weight space, which lay the foundation for the lightweight design of the bed.
Simulation and Optimized Analysis of Channel for Injection Molding of Bottle Cap Based on Moldflow
Authors: Zhang Cong , Han Lei Lei , Yang De , Zhang Hui Min
Published: February 2014

A simulation optimization of a two-cavity injection molding for the bottle cap was studied. It included the preprocessor of the model, scheme one which used a series recommended parameters from Moldflow software. Though the result could meet surface quality requirements, the mold structure was too complicated especially the channel. The deformation of different factors were analyzed and uneven cooling had little effect on the deformation. And some relative heat condition equation were used to calculate the channel number. Therefore the optimized scheme two was put forward. According to the cooling circuit and deformation factors, the channel number was greatly reduced. After the simulation, scheme two could also meet surface quality requirements. At the same time, the mold structure can get simplified.
FTAe – Fault Tree Analysis in Microsoft Excel
Authors: Kuracina Richard , Šandor Denis , Balog Karol
Published: February 2014

FTAe is software tool for Fault Tree Analysis in Microsoft Excel. This paper is focused on short description of created FTAe. A brief description of Fault Tree Analysis is in the first part of paper. The Structure, Logic and Minimal Cut Sets in Fault Tree analysis is described too. Next part of this paper is focused on the choice of algorithm for cut set calculation and brief description of structure of FTAe. Finally, advantages of FTAe software in Microsoft Excel are described in conclusions.
Structural Topology Optimization Using Turing Model
Authors: Rahman Kaysar , Halik Azhar , Samsak Kahar , Helil Nurmamat
Published: February 2014

In this paper firstly a new hypothetical model of bone remodeling based on bone bioactivity mechanism and Turing reaction-diffusion equations is presented. Secondly this model of bone remodeling is translated to material formation and resorption process of continuum structures, a new heuristic structural topology optimization is presented. Finally short cantilever beam problem, one of the widely used examples in structural topology optimization are carried out by using present method to confirm the validity of the proposed topology optimization method.
New Algorithms for Solving Minimum Path Sets of Fault Tree Analysis and its Applications
Authors: Dai Zhang Yin
Published: February 2014

With analyzing the shortcomings of "Success Tree" method, the article proposed two new algorithms which base on the basic principles of Boolean algebra and Fussell determinant method respectively to replace the "success tree" method to solve the minimum path sets of fault tree. Combined with the simple and the complex examples' results, the correctness and effectiveness of new algorithms were verified. Especially for the large and complex fault trees, the solving process of these new algorithms can be simplified sharply. Furthermore, the new algorithms could provide the algorithm support for the realization of quantifying the qualitative analysis, modeling the quantitative analysis, and computerizing the model analysis.
Multi-Objective Model and Heuristic Algorithm for Billet Stacking Problem in Steel Production
Authors: Shi Can Tao , Dong Guang Jing , Ma Yi Wei
Published: February 2014

Aiming at billet stacking problem of the rolling mill, a multi-objective programming model is established. Billets on the roller are batched by clustering algorithm and then assigned to the warehouse stack positions by improved Clustering-based Best Fit algorithm (CBF). The utilization of non-empty warehouse stack positions and shuffles are considered in the algorithm. Compared to existing artificial calculation method, the proposed algorithm can not only reduce the shuffles significantly, but also improve the space utilization of warehouse stacking positions.
A New Heuristic Topology Optimization Method Based on Bone Remodeling Model
Authors: Rahman Kaysar , Samsak Kahar , Halik Azhar , Helil Nurmamat
Published: February 2014

The law of bone remodeling asserts that the internal trabecular bone adapts to external loadings, reorienting with the principal stress trajectories to maximize mechanical efficiency creating a naturally optimum structure. In this paper a new heuristic topology optimization method based on ordinary differential equations describing bone remodeling process is presented. The basis for numerical algorithm formulation was the phenomenon of bone adaptation to mechanical stimulation. The resulting optimization system allows fulling mechanical theorem for the stiffest design by use of presented heuristic topology optimization approach. Two widely used numerical examples are shown to confirm the validity and utility of the proposed topology optimization method.
Numerical Simulation Study of Concrete Beam with Bonding Steel Plates Bending Failure
Authors: Song Li , Wei Sai Ping , Gu Lin , Fan Cheng
Published: February 2014

In the sphere of the consolidating technique of the engineering structure the new and developing theory of the steel adhered reinforcement has gradually applied to the practical engineering. Reinforcement steel structural adhesive is a method using steel plate pasting on the component surface to improve bearing capacity of the structure, which is widely used in reinforced concrete bending, eccentric compression and tension reinforcement. In this paper, based on continuum damage theory and statistical strength theory, Starting from each phase of the concrete, medium micro softening plasticity and strain of non-uniform, Numerical simulation of steel bonded reinforcement bending failure of concrete beam was carried out and Analysis of the crack propagation and failure form were put forward. Based on FEM analysis, the size of material and binder were selected reasonably, ensuring the safety and durability of concrete beams, provide technical support for the practical engineering as well.
Remote Fault Diagnosis System Based on EMD and SVM for Heavy Rolling-Mills
Authors: Liu Jin Fei , Chen Ming , Gu Jia Yun , Cheng Lu
Published: February 2014

Aiming at the requirements of fault diagnosis for heavy mills, the architecture of remote fault diagnosis system based on EMD and SVM for heavy mills is built. Then the function of 3 main subsystems in the prototype system is introduced: Pattern recognition subsystem is used to evaluate healthy state of equipment with SVM classification algorithm; Fault location subsystem is used to fix fault position in the equipment with the method of Empirical Mode Decomposition and Hilbert-Huang Transform; Remaining life prediction subsystem is used to make a prediction of equipments health trends with SVM regression algorithm. At last, a remote fault diagnosis system based on website is established.
A Study on Obstructive Sleep Apnea by Using MindSet Platform
Authors: Qiao Dan Yang , Guo Yi Jing , Lin Bin , Zeng Hai Hang , Qiu Qin Xiu , Wu Jun Ying
Published: February 2014

BCI technology as a widely used technique is gradually into daily life. Based on the study of this technique and taking advantage of MindSet extraction equipment of EEG which is available in the market, we design a portable sleep apnea monitoring tools which use MindSet as a platform, which has comfortable pillow structure. Monitoring equipment described in the text achieves real-time monitoring for apnea, also has an alarm function. Apnea syndrome on self-monitoring and alarm has better effects.
Base on Double Thermocouple the Casting Powder Crystallization Measurement
Authors: Ma Qiong , Xie Dong
Published: February 2014

This paper proposed the measuring device for the casting powder crystallization and the crystalline proportion test by the double thermocouple. The two different dual platinum-rhodium thermocouple wires are acted as heating element and temperature measurer at the same time, so that, the temperature of both wires apart can be controlled accurately. Adjusting the two wires distance discretionarily, the crystalline state can be observed under the different range of temperature of flux film on the both sides. The fast temperature raising and high efficiency of metering technology is designed for the measurement device and achieved great sense to research the casting powder characters in the crystallizer.
Design of Side Line Short Circuit Detection Device Load of Low Voltage Circuit Breaker before Closing
Authors: Meng Xiang Fei , Li Zhi Chao
Published: February 2014

It uses MSP430F2274, the ultra low power microcontroller, as the control core of short circuit detection device, through the accurate measurement of low voltage circuit breaker load side of the main wiring of insulation resistance value and the interphase insulation resistance value, outputting high voltage startup sound and light alarm device, and then accomplish the open circuit fault detection. Testing power supply is the use of magnetic coupling resonance principle, from the main power grid electrical insulation for short circuit detection device. The device has the advantages of low cost, small volume, good safety, good detection effect, and can be embedded in use in low voltage circuit breaker.
Vibration Frequency Spectrum Measurement on a Hydraulic Turbine Runner Chamber for a Large Bulb Hydraulic Generator Set
Authors: Huang Chang Zheng , Li Jin , Yang Zu Chao
Published: February 2014

The vibration is severe for a hydraulic turbine runner chamber of a large bulb hydraulic generator set. A measurement and analysis system is composed of an acceleration transducer, a charge amplifier, and a dynamic data collecting & analyzing system. It is used to test the frequency spectrum, which provide a basis for the optimization design based on the modal analysis, so that its natural frequencies can stagger these frequencies of vibration sources, the resonance does not occur and the vibration is reduced.
The Study on Measurement Method of Glass Melts' Surface Tension at High Temperature
Authors: Tian Ying Liang , Guo Shu Guang , Wu De Long
Published: February 2014

At high temperature conditions, the glass molten by the combined action of gravity and surface tension form an oval. Through digital image measurement system we can obtain glass molten oval contours and the contact angle. By the Bashforth-Adams equation which deduced from Young- Laplace equation to obtain the glass molten' surface tension at the corresponding temperature conditions. This method has good reproducibility and accuracy.
Real-Time Temperature Monitoring System Design Based on MATLAB GUI
Authors: Xue Fei , Yang You Liang , Dong Fu Tao
Published: February 2014

A temperature real-time monitoring system was devised based on MATLAB GUI. It improved the data processing speed and software development efficiency. Serial port tool box in MATLAB and Modbus communication protocol were used to link up thermostat to PC. Variety operating modes can be achieved in different parameter configurations. The software source file is 304 KB. Test results show that, the temperature response curves of different parameters configuration are quite accurate. The sampling interval was 1s and the measurement accuracy was 0.1°C.
Research on Low-Voltage Series Arc Fault Detection Based on Higher-Order Cumulants
Authors: Yang Kai , Zhang Ren Cheng , Yang Jian Hong , Wu Xiao Mei
Published: February 2014

Arc faults are one of the main reasons of electrical fires. For the difficulty of series arc fault detection, very few of techniques have successfully protected loads from arc faults in low-voltage circuits, especially in China. When series arc faults occur, shoulders will appear in load currents. The shoulder widths of non-arc faults such as normal load arcs are stable, while those of arc faults are variable because the appearance of arc faults is erratic. Therefore, a novel detection method based on shoulder characteristics was proposed. To better capture shoulder widths, original currents were firstly converted into pulses. Then, the pulse widths were used to detect arcs and the fourth-order cumulants of their differential were used to distinguish arc faults from normal operations. Finally, an arc fault detection device (AFDD) prototype was developed for test. The results show this prototype can discriminate arc faults effectively from normal operations.
Study on Phase Shifting Algorithm and System of White Light Interference
Authors: Deng Lin Juan , Fu Yu Xia , Cai Xiao Yu , Li Yuan , Lei Li Hua , Zhao Dong
Published: February 2014

The white-light interferometry (WLI) has been widely used in 3D topography measurement. This paper introduces a white light phase shifting method for interferometry with the combination of Hariharan phase shifting and WLI. A micro/nanolevel mechanic system was designed and built for the experiments. To verify system accuracy and feasibility, a 100nm step height standard was measured by the designed system and the metrological nanomeasurement machine (NMM). Results of 102.7nm and 102.5nm are obtained respectively. En value of 0.14 is calculated, demonstrating the reliability of result measured by the system. Based on classic nanoquantity traceability system, the measurement results can effectively traced back to the definition of nanometer magnitude, which can improve the accuracy of measurement.
Error Compensation Method for Mine's Automatic Light Rail Weight-Bridge
Authors: Zheng Chuan Xing , Chen Jian
Published: February 2014

The method of wheel-weight for mine's automatic light rail weight-bridge is put forward. According to some important factors which cause measure error using wheel-weight method, for example, zero drift, speed and gradient, the error compensation algorithms are studied. The software flow charts of these algorithms are given, which have been put into effect in the ARM microprocessor based embedded system. It has been found that these error compensation methods are efficient to improve the accuracy of the measurement system.
Application of an Improved Wavelet Threshold Denoising Method for Vibration Signal Processing
Authors: Xie Zhi Jie , Song Bao Yu , Zhang Yang , Zhang Feng
Published: February 2014

Vibration signal analysis has been widely used in the fault detection and condition monitoring of rotation machinery. But the practical signals are easily polluted by noises in their transmission process. The raw signals should be processed to reduce noise and improve the quality before further analyzing. In this paper an improved wavelet threshold denosing method for vibration signal processing is proposed. Firstly, a new threshold is developed based on the VisuShrink threshold. The effect of noise standard deviation and wavelet coefficient is retained, and the correlation of wavelet decomposition scale is considered. Then, a new threshold function is defined. The new algorithm is able to overcome the discontinuity in hard threshold denoising method and reduce the distortion caused by permanent bias of wavelet coefficient in soft threshold denoising method. At last five kinds of threshold principles and three kinds of threshold functions are compared in processing the same signal, which is simulated as the mechanical vibration signal added white noises. The results show that the improved threshold is superior to the traditional threshold principles and the new threshold function is more effective than soft and hard threshold function in improving SNR and decreasing RMSE.
Passive Strain Transfer Analysis of Wireless SAW Torque Sensor
Authors: Wang Li Jiu , Zhang Yun Tao , Li Xi Peng
Published: February 2014

When detecting torque with surface acoustic wave (SAW) resonator sensors, the real strain of the host structure is not exactly consistent with the strain of SAW resonator due to material mismatch and the finite-thickness adhesive problem. A 3-layer (host structure, adhesive, and resonator layer) model is established. Finite-element Analysis (FEA) was used to investigate the strain transfer from the metal substrate to the SAW resonator (SAWR) through a bonding layer. The results show that the values of the strain transfer rate of FEA agree well with the experimental data. It can be concluded that FEA is of great value for SAW sensor design and sensing applications.
Modeling and Simulation of Airflow Omnibearing Posture Sensor
Authors: Yang Qi Rui , Piao Lin Hua , Tian Wen Jie
Published: February 2014

In order to improve the performance of sensor, Using ANSYS software, the three-dimensional finite element modelling method and simulation results of micromachined airflow omnibearing level posture sensor are presented. The results show that: (1)Using the sense organ’s symmetry characteristic, a half model is built first, which is convenient for modelling and observing the simulation results;(2) Gridding should be meshed more densely where fluid grads is large, which is helpful of saving simulation time and improving precision. Compared to two-dimensional modeling, the simulation results of three-dimensional modeling are more comprehensive and exact, which provides dependable basis for further research of the sensor.
Research of Micro Airstream Gyroscope Sensitive Mechanism
Authors: Yang Qi Rui , Piao Lin Hua , Tian Wen Jie
Published: February 2014

The sensitive mechanism of micro airstream gyroscope was explained by calculating the distributing of stream field in the sense organ. According to the real size of micro airstream gyro-scope, ANSYS-FLOTRAN CFD was used to create models and work out the gas flow field and distributing in the two-dimensional chamber with different angular velocities. The results show that while the gyroscope in a static state the gas velocities at both hot-wires are equal as well as the current, and the output voltage is zero. On inputting an angular rate the gas velocities differ and a voltage signal proportional to the input angular rate is achieved.
Research and Design of Gardon Heat Flux Sensor
Authors: Yu Jing , Bu Xiong Zhu , Chu Xiao Gang
Published: February 2014

In the field of aerospace, the Gardon heat flux sensor is not allowed water-cooling device, so the sensor sensitivity would be greatly affected by the temperature rise of the heat sink. To deal with this problem, a high-temperature, high-precision heat flux sensor is designed based on the metal thermo-electric effect and the principle of thermal conduction. First of all, the measuring principle of the Gardon heat flux sensor is expounded. Then the heating process of the copper heat sink is derived. In order to slowdown the temperature of the heat sink, kinds of adiabatic measures are taken. Thermodynamic simulation for the designed sensor is performed by the ANSYS finite element simulation software. Finally, experiments have been carried out to test the performance of the sensor. The experimental results show that the sensitivity of the sensor with adiabatic measures did not decline within 1000s, and its linearity is 1.38%. So the sensor is able to meet applications in the aerospace field.
Implementation of RLC Layer in the Terminal Side of TD-LTE
Authors: Chen Fa Tang , Zhu Ming
Published: February 2014

This paper focuses on the overall implementation process of RLC Layer in the Terminal Side of TD-LTE, which is based on the Nucleus Plus operating system. It contains primitive processing procedure and the realization of RLC layer entry function, which contains multi-instance module and state machine processing module. This helps to learn RLC layer and grasp the overall protocol stack.
The Optimization and Improvement of Truck Brake Caliper Bracket Based on the Finite Element Method
Authors: Lei Ming Xing , Cao Qin , Wang Yan , Xia Peng Fei
Published: February 2014

The brake caliper bracket (BCB) of the truck front axle would crack when a certain truck is running in 20000 kilometers road test. In view of the above phenomenon, this paper will use Altair HyperWorks to analyze the static strength of the BCB according to its working principle and load cases. The topology optimization will be done based on the reason found out before. Form the result of the topology optimization, the modified design for the BCB is carried out. Finally, an experiment result is given to check it is correct.
Experiment and Technical Research on Underwater Sonic Device Emitted by Electric Sparks with High Energy and Large Bandwidth
Authors: Su Hang , Wang Yu Zhe , Zhang Ru Bo , Wu Wei Min
Published: February 2014

Combined with practical research project, a novel discharge method using high voltage pulsed power technology was put into practice for a special kind of underground sonic source device. The sonic source guaranteed large power as well as broad and thick sonic wave. Simulation as well as field test confirmed the correctness and effectiveness of the design method.
The Implementation of In-Band FM Based on Fractional-N PLL
Authors: Han Yao , Qin Kai Yu
Published: February 2014

This paper studied the in-band frequency modulation technology based on fractional-N PLL, first elaborated the basic principle and transfer function analysis of FM PLL, and according to the fractional-N theory gives the realization principle and the concrete algorithm of the modulation signal frequency in the loop modulation loop bandwidth of PLL, gives the design of key circuit, and the result shows that the technology can realize the frequency of modulation signal low to the DC, and high precision modulation, good frequency stability.
Study on Intelligence Fault Diagnosis Approach Based on Digraph Model and Application to Satellite Battery
Authors: Cui Zi Qian , Xu Min Qiang , Wang Ri Xin
Published: February 2014

This article presents a SSDG---based intelligent fault diagnosis method. This method uses five signed threshold value modes to define nodes for carrying quantified information. This method establishes the SDGs of the system and its components, uses the based on rules method to diagnosis, then expands the diagnosing rule bank with logical operators to construct the diagnosing rule bank of the system. Applying in satellite battery system, this method can diagnosis the multiple fault, and batter explain, reworked and faster diagnosis.
Modeling and Simulation of Brushless DC Motor Speed Control System Based on SPWM
Authors: Wu Shuo , Ma Guang Jun
Published: February 2014

This paper introduces the composition of double closed loop DC speed control system of DC motor speed and current, it is described the working principle of DC PWM converter and the calculating method of the pulse width modulation technology. Using the Matlab software to the induction motor system of modeling and simulation based on the technology of SPWM . Observed in the steady state and dynamic system using SPWM control mode and the influence of control parameters. Finally, experimental results show that the SPWM technology for effective control of double closed loop DC speed control system
Driver Model Based on Controller with Open and Close Loop
Authors: Chen Huan Ming
Published: February 2014

It is very important to simulate driver's manipulation for people - car - road closed loop simulation system. In this paper, the driver model is divided into two parts, linear vehicle model is used to simulate the driver's driving experience, and closed-loop feedback is used to characterize the driver's emergency feedback. The lateral acceleration of vehicle is used as feedback in closed loop control. Simulation results show that the smaller lateral acceleration requires the less closed-loop feedback control. The driver model can accurately track the target path, which can be used to simulate the manipulation of the driver. The driver model can be used for people - car - road closed loop simulation to evaluate vehicle handling stability.
Measurement of Residual Stresses in Titanium Aerospace Components Formed via Additive Manufacturing
Authors: Hoye Nicholas , Li Hui Jun , Cuiuri Dominic , Paradowska Anna M.
Published: February 2014

In the present study gas tungsten arc welding (GTAW) with automated wire addition was used to additively manufacture (AM) a representative thin-walled aerospace component from Ti-6Al-4V in a layer-wise manner. Residual strains, and hence stresses, were analysed quantitatively using neutron diffraction techniques on the KOWARI strain scanner at the OPAL research facility operated by the Australian Nuclear Science and Technology Organisation (ANSTO). Results showed that residual strains within such an AM sample could be measured with relative ease using the neutron diffraction method. Residual stress levels were found to be greatest in the longitudinal direction and concentrated at the interface between the base plate and deposited wall. Difficulties in measurement of lattice strains in some discrete locations were ascribed to the formation of the formation of localised texturing where α-Ti laths form in aligned colonies within prior β-Ti grain boundaries upon cooling. Observations of microstructure reveal basket-weave morphology typical of welds in Ti-6Al-4V. Microhardness measurements show a drop in hardness in the top region of the deposit, indicating a dependence on thermal cycling from sequential welds.
Micromechanical Behavior of Solid-Solution-Strengthened Mg-1wt.%Al Alloy Investigated by In Situ Neutron Diffraction
Authors: Lee Soo Yeol , Woo Wan Chuck , Gharghouri Michael A. , Yoon Cheol , An Ke
Published: February 2014

In-situ neutron diffraction experiments were employed to investigate the micromechanical behavior of solid-solution-strengthened Mg-1wt.%Al alloy. Two starting textures were used: 1) as-extruded then solutionized texture, T1, in which the basal poles of most grains are tilted around 70~85° from the extrusion axis, and 2) a reoriented texture, T2, in which the basal poles of most grains are tilted around 10~20° from the extrusion axis. Lattice strains and diffraction peak intensity variations were measured in situ during loading-unloading cycles in uniaxial tension. Twinning activities and stress states for various grain orientations were revealed. The results show that the soft grain orientations, favorably oriented for either extension twinning or basal slip, exhibit stress relaxation, resulting in compressive residual strain after unloading. On the other hand, the hard grain orientations, unfavorably oriented for both extension twinning and basal slip, carry more applied load, leading to much higher lattice strains during loading followed by tensile residual strains upon unloading.
Investigation of Residual Stresses Distribution in Titanium Weldments
Authors: Song Shao Pin , Paradowska Anna M. , Dong Ping Sha
Published: February 2014

Titanium and its alloys have increasingly become a material of choice for applications in high-performance structures due to their superior corrosion resistance and high strength-to-weight ratio. However, in contrast to conventional steel alloys, there exist little design and manufacturing experience in the heavy fabrication industry with large welded structures made of titanium materials. In addressing the above concern, the University of New Orleans funded by Office of Naval Research (ONR) initiated program on investigation of manufacturability and performance of a titanium mid-ship section. The uniqueness of this program is its focus upon a representative full-size mid-ship section upon which relevant scientific and technological challenges are simulated and experimentally validated. This paper reports the measurements of residual stresses using neutron diffraction in titanium T-joints. The residual stresses were measured using Engin-X at ISIS (UK) and the Kowari Strain Scanner at ANSTO (Australia). This experimental research was used to validate our in house predictions and significantly improved the knowledge and understanding of the welding process of titanium alloys.
Evaluation of Ductile Damage Progress of Aluminum Single Crystal with Prior Activity of Single Slip System under Tensile Loading by Using Synchrotron White X-Ray
Authors: Shibano Junichi , Kajiwara Kentaro , Tsukamoto T. , Kawai H. , Miura Setsuo , Zhang Shuo Yuan , Shobu Takahisa , Kobayashi Michiaki
Published: February 2014

A ductile damage progress of an aluminum single crystal with the prior activity of the single slip system under tensile loading was verified by a profile analysis using white X-ray obtained in BL28B2 beam line of SPring-8. In this study, the aluminum single crystal of the purity 6N was used as a specimen prepared in I-type geometry for tensile test. A notch was introduced into one side of the center of a parallel part of the specimen by the wire electric discharge machining. White X-ray beam, which has 50 μm in both height and width, was incident into the specimen on the Bragg angle θ of 3 degrees using energy dispersive X-ray diffraction technique. The specimen was deformed by elongation in the direction of 45°to [11 and [11 crystal orientations, respectively, and a diffraction profile of the white X-ray from Al220 plane was analyzed. In profile analysis, an instrumental function was defined in consideration both of a divergence by a slit and a response function peculiar to the energy dispersive method. The Gauss component of integral breadth related to non-uniform strain and the Cauchy component of integral breadth related to crystallite size were determined by eliminating the broadening by the instrumental function from the diffraction profile of white X-ray. As a result, the characteristics of ductile damage progress near the notch of the aluminum single crystal were inspected from the distribution of both non-uniform strain and dislocation density.
Residual Stresses in a Welded Zircaloy Cold Neutron Source Containment Vessel
Authors: Bendeich Philip , Luzin Vladimir , Law Michael
Published: February 2014

Zirconium alloys are widely used in the nuclear industry because of their relative high strength, neutron transparency, resistance to high neutron-irradiation environment and corrosion resistance. One application for Zirconium alloy Zr-2.5Nb is the vacuum confinement vessel utilised in the cold neutron source of the OPAL research reactor at ANSTO. Having a total length of more the 3 meters, it is made of two sections joined using electron beam welding. The weld and the nearby regions are critical for the performance and integrity of the component and therefore understanding of the residual stresses development within the weld is important in connection to (i) evolution of fine dual phase α/b microstructure and crystallographic texture (ii) and stress-related radiation induced phenomena, such as grain growth, creep and sub-critical crack growth by delayed hydride cracking.
The stresses were measured in and around an electron beam weld produced during the development of this component of the OPAL Cold Neutron Source. The effects of a large grain size in the weld were reduced by taking advantage of rotational symmetry and rotating the sample to increase the swept volume. Due to the heat-treatment after welding, the stresses were very low, less than 10% of the yield strength of the material, in both the hoop and axial directions. As a result of phase transformation effects during the welding process the final stresses are compressive in the weld, which reduces the likelihood of fracture or of hydride formation in this region. The highest stresses are in the parent material adjacent to the weld where the toughness is expected to be higher than in the weld material.