bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis on the Lightning Current Model
Authors: Wang Ying , He Wei , Zhou Zhen Zhu , Zhu Chun Dan
Published: November 2012

Through the analysis of characteristic of lightning currents, this paper expounded the lightning current wave-form and the primary parameters of it. The previous lightning current models contain only two parameters, wave tail time constant and the peak current value, which is imperfection. In order to solve this problem, a new lightning current model with the additional parameters such as lightning channel radius and velocity of the return stroke was proposed. On the basis of lightning current parameters and wave-form characteristic, we compared the new lightning current model with the double exponential function model, Hodler model and impulse function model. And then the distinctions among the four different models were received and the wave-form of the new model accorded with the characteristic of really lighting current wave-form well. On the other hand, the advantages and disadvantages about the new lightning current model were explained. This new lightning model provides the theoretical basis for further study of lightning electromagnetic field.
Analysis and Suppression Strategy of Harmonics for SPWM Inverter
Authors: Li Xin Jun
Published: November 2012

The three-phase voltage type SPWM inverter output voltage and current harmonic and its generation rule is discussed. And put forward a new easy to implement harmonic suppression strategy, the method through the correct choice of the carrier frequency and the sinusoidal wave superimposed on a three wave makes saddle shaped wave, to produce a corresponding SPWM waveform control inverter switch on-off thus improving the output waveform. Mathematical analysis shows that is helpful to reduce the output voltage THD ( waveform distortion factor ), improved harmonic current loss and torque characteristics, the simulation results prove the validity of these measures and practical.
The Compatibility Assessment between Voltage Sags and Equipment Tolerance Based on Fuzzy-Random Method
Authors: Yuan Zhi Jian , Li Yan
Published: November 2012

The impact of voltage sags on equipment is usually described by equipment failure probability.It is generally difficult to assess and predict the probability because of the uncertainty of both the nature of voltage sags and the VTL (VTL) of equipment. By defining the equipment failure event caused by voltage sags as a fuzzy-random event, a fuzzy-random assessment model incorporating those uncertainty is developed. The model is able to convert the probability problem of a fuzzy-random variable to that of a common random variable by using λ-cut set. It is thus valuable in theoretical analysis and engineering application. The validity of the developed model is verified by Monte Carlo stochastic simulation using personal computers (PCs)as test equipment.
Static Analysis and Electromotor Power Calculation of the Bisectional Astronomical Dome
Authors: Liu Ping
Published: November 2012

The snow and wind loading model of a bisectional astronomical dome was established. The press of the astronomical dome has been calculated. With the analysis of the loading mode of the dome when it was opening or closing, the maximum power of the electromotor has been calculated. The results are very valuable for calculating the snow and wind loading and designing the maximum power of the electromotor of the bisectional astronomical.
A Novel Electronic Current Transformer for High Voltage Systems
Authors: Song Tao
Published: November 2012

This paper illustrates a novel electronic current transformer (ECT) with a power source at ground potential. Employ the insulation structure of the traditional transformer insulated by SF6, the sensing unit with an air-core coil for measurement and protection transmits the electrical signal to the signal processing unit at the ground potential. Then the optical power source could be abandoned and the reliability is effectively enhanced. Utilizing mathematical models, designations and emulations have been done to compute the influence of the ambient temperature. Tests have been done and the experimental results show that this ECT meets the requirement of the 0.2s class for measurement and 5PTE for protection in IEC60044-8 respectively.
Research of TCSC Damping Effect on Low Frequency Oscillation in West Yunnan Power Grid
Authors: Qiu Ge Fei , Lin Zheng , He Li Jun , Cao Jun Hao , Dan Xiao
Published: November 2012

Based on the analysis of damping theory of Thyristor Controlled Series Capacitor (TCSC), the influence of TCSC to electric magnetic torque with and without damping function is studied by one generator infinite model so to deduce the mechanism of low frequency oscillation damping of TCSC. Combined with ‘the Twelfth Five-year Plan’ power and transmission grid construction plan in western Yunnan, the proper scheme for TCSC damping control was chosen in the southwestern Yunnan power grid and the transient and dynamic simulations of southwestern Yunnan power grid were performed. The simulation results show that TCSC can improve the system damping when the grid is in Yunguang area oscillation mode with frequency of 0.27Hz and 0.6Hz，especially in condition when Yunnan grid is in the local area oscillation mode of 0.6 Hz. The simulations also demonstrate that TCSC can improve transient stability of Yunnan power grid. The application of TCSC in southwestern Yunnan Power Grid is of great significance to power grid safe operation.
A High Precise Automatic Test Platform for the Boards of Wind Power Converter
Authors: Fan Shi Cai , Li Wen Ru , Peng Tao
Published: November 2012

As the core component of wind turbine generator system, the quality of wind power converter attracts great attention. Traditionally, manual testing has been the way to ensure the board performance. Based on virtual instrument, a hardware-in-the-loop test platform is designed using the LabVIEW graphical programming language. A method based on FFT spectrum analysis shows high precision in detection the phase shift of current signals, which would outperform the zero-crossing method when noises could not be omitted; and a method based on BP neural network improves the calibration precision of temperature detection channels. The satisfying precision and efficiency in application show great advantage in many aspects compared to the traditional testing method.
The Research of a Derivation Calculation Method for the Maximum Power Point in Grid-Connect Photovoltaic System
Authors: Wang Yu Xin , Zhang Feng Ge , Yin Xiao Ju , Zhu Shi Lu
Published: November 2012

A derivation calculation methods for the maximum power point tracking is proposed in this paper. This method is the direct calculation method for the maximum power point tracking, through the calculation of the derivative value of the power to voltage, adjust the change values of occupies emptiescompared, which is used to deduce the voltage and current value, judge whether the derivative of the power to the voltage is zero, if it is ture, the maximum power point is got. Hardware is used the method to regulate the duty ratio of PWM in DC/DC boost circuit ,though once sampling, it can calculate the value of voltage and the duty ratio at maximum power point. The prototype experiments using DSP2812 chip verify that the inverter can better realize the most power tracing, high accuracy, and the system has the high stability.
Influence of a Flux-Coupling Type Superconducting Fault Current Limiter on Power System Transient Stability
Authors: Qiu Ge Fei , Cao Jun Hao , Xu Zi Qing , Song Meng , Chen Lei , Zheng Lin , Xiao Dan
Published: November 2012

In this paper, the influence of superconducting fault current limiter (SFCL, flux-coupling type) on power system transient stability is studied in detail. The influence of SFCL to transient stability of power system is studied using a model of single generator infinite bus system, different transient stability calculation results gotten with and without SFCL and with model system in different fault conditions are compared. The results show that the SFCL can effectively reduce the transient swing amplitude of rotor and extend the critical clearance time, and the application of SFCL in the power system can help to enhance its transient stability.
Design and Analysis of MW-Level High Speed Permanent Magnet Machine
Authors: Zhang Feng Ge , Huang Na , Du Guang Hui
Published: November 2012

This paper presented a novel high speed permanent magnet machine, which is used for electric drives and motion control systems. Compared to traditional high speed permanent magnet machines, the proposed structure can increase the cooling capacity and reduce the core loss, which can improve the reliability of the system and efficiency. Meanwhile, in order to protect the permanent magnet, the carbon fiber bandage with thin layer of conductive metal is used to cover the permanent magnet. The basic design principle for the proposed structure is described. To verify the proposed structure, finite element method (FEM) is adopted to get the characteristics of the proposed structure. Finally, the validity of the proposed structure was verified by the FEM analysis results.
Energy Consumption Model for Wireless Sensor Networks
Authors: Chen Shuai , Chen Ling Ling , Shu Ren Yi
Published: November 2012

With the energy consumption, the new route may be reconstructed with energy sufficient nodes. In order to evaluate energy of nodes, an energy consumption model was raised to calculate node energy in wireless sensor networks. The model of nodes was setup in data structure, the energy consumption model was setup in the rule of energy consumption and the wireless radio model of wireless sensor networks was setup in the rule of wireless radio. The simulation algorithm was designed and realized. The result shows that the model can simulate energy consumption for wireless sensor networks which is helpful for route algorithm.
Design of a USB OTG Mass Storage Module Based on LM3S9B90
Authors: Zang Jie , Wang Xiao Li , Yan Zhong Hua
Published: November 2012

This paper introduces the method of design a USB On-The-Go (OTG) mass storage module according to USB 2.0 specification, which bases on embedded systems LM3S9B90. This module’s hardware system and software system is described, focusing on the implementation of USB host system. The module realizes USB OTG function, not only can realize functions of read and write USB mass storage devices, but also can exchange data with USB host as a USB mass storage device, can be used as an extension of USB system and has good application value.
Measurement of ARJ21 Aircraft Landing Gear Noise Using Array Signal Processing Technology
Authors: Chen Tao , Hou Hong , Chen Zhi Fei , Jiang Cheng Kun
Published: November 2012

Flyover noise measurements were conducted on an aircraft ARJ21 aiming at landing gear noise prediction schemes. The analysis is based on acoustic dedopplerized spectra and localization maps was calculated with the pressure signals of a acoustic phased array with 30 microphones. The acoustic phased array is a spatially distributed set of microphones which simultaneously sample the acoustic field. The doppler shifts was removed using linear interpolation.By appropriately time delaying the output of individual microphones, the origin and level of noise source(the landing gear) can potentially be determined. The success of this approach depends largely on the phased array design, and the array data processing method. This paper focuses on the two areas.
Designation of Image Acquisition Module Based on the C8051F340
Authors: Zhang Xin Bin , Li Shi Zhong
Published: November 2012

The image data acquisition module mainly completes the collection of image data and transmits the collected data to the wireless transmission module. This paper mainly discusses the hardware components of the image acquisition module and software implementation. The collected image quality influences image processing, therefore the choice of image sensor is an important part of this system. This is a OV7670 image sensor. The master controller uses C8051F340 MCU. C8051F MC’s frequency has been greatly improved compared with ordinary 51 MCU, and has the advantages of simple structure, interface expansion capability, low prices and better performance.
Low-Power Design for Battery Management System
Authors: Li Shuo , Liu Xiao Jun , Dong En Qing , Xiao Xiao Chao
Published: November 2012

This paper designs a Battery Management System (BMS) based on MCU C8051F350 for 4 series Li-ion battery. It implements the functions of battery pack charge and discharge protection, status display, voltage, current and temperature parameter acquisition and accomplishing RS232 communication between MCU and PC. The analysis of the low-power processing is focused on in the circuit design process. Experimental result shows that this design can reduce power consumption of BMS effectively.
Research on the Repeater Optimization Based on Voronoi Model
Authors: Liu Ban Teng , Hu Xi Lin , Xu Zheng Yu , Liu Yao Lin , Chen You Rong
Published: November 2012

This paper propose a two-tiered network in which lower-power users communicate with one another through repeaters, which amplify signals and retransmit them, have limited capacity, and may interfere with one another if their transmitter frequencies are close and they share the same private-line tone. Motivated by cellular networks, this paper gives a naive solution where the number of repeaters and their positions can be obtained analytically. In a circular area with radius 40 miles, 12 repeaters can accommodate 1,000 simultaneous users. This paper further propose an iterative refinement algorithm consisting of three fundamental modules that draw the Voronoi diagram, determine the centers of the circumscribed circles of the Voronoi regions, and escape the local optimum by using external optimization. The algorithm obtains a solution with 11 repeaters, which we prove to be the absolute minimum. For 10,000 users, it uses 104 repeaters, better than the naive solution's 108.
The Automatic Positioning System of Coke Oven Locomotive Based on Radio Frequency Identification and Image Processing
Authors: Zhang Yong Tao , Wu Lan , Bo Jing Dong , Li Qing Ping , Zhang Jing Xuan
Published: November 2012

Proposed the design method that separation of coking chamber’s number identification and accurate position. Researching new coke oven locomotive positioning system application of radio frequency identification and image processing technology, use radio frequency identification technology on accurate identification of coking chamber’s number, and then use the video camera to identify door image and its center point for accurate positioning of coke oven locomotive.
Electrochemical Oxidation of Ce(III) to Ce(IV) in Mixed Acid (H2SO4 and CH3SO3H)
Authors: Zhao Hua Li , You Qun Chu , Chun An Ma
Published: November 2012

Electrochemical behaviors of Ce3+/Ce4+ couple in mixed acid (H2SO4 and CH3SO3H) were investigated on Pt electrode. Polarization curves and electrochemical impedance spectroscopy (EIS) were used to optimize mixed acid composition, and the mixed acid consisting of 1.0 M methanesulfonic acid (MSA) and 0.8 M sulfuric acid is singled out as the optimum electrolyte. Subsequently, the effects of current density and electrolyte temperature on the electrochemical oxidation of Ce3+ to Ce4+ were researched. A 92.2% current efficiency was achieved at 40 mA•cm-2 in cerium (III) solution with the optimum mixed acid electrolyte above at 313 K. It can satisfy the application of mediated electrochemical oxidation process with Ce3+/Ce4+ mediator.
Research of GPS Signal Multipath Effects Based on GAMIT TRACK
Authors: Lu Bo , Jin Jian Ping , Duan Wen Yi , Chen Liang Jin , Guan Hong Ye
Published: November 2012

GPS multipath disturbance is a bottleneck problem that limits accuracy of GPS positioning. The function of single epoch kinematic positioning of GAMIT TRACK is used to study GPS signal multipath effects. A filtering method for separating signal and noise based on the wavelet analysis is established. The decomposition level for wavelet filter is confirmed according to the high correlation of the multipath effects between adjacent sidereal days by using the maximum correlation coefficient method. The accurate multipath corrections in GPS coordinate series are acquired with the proposed method making use of TRACK and the repeating property of multipath effects is used to weaken multipath effects in subsequent days, and therefore improve the precision of the GPS positioning.
A 12-Bit 1GS/s Current-Steering DAC with Matching Capacitor in Switched Current Cell
Authors: Xue Xiao Bo , Si Hong Wei , Shi Qi Feng , He Le Nian
Published: November 2012

This paper presents a 12-bit 1GS/s current-steering DAC with matching capacitor in switched current cell, which has been designed to enhance the DAC’s dynamic performance. Compared with traditional designs, the switched current cell with an matching capacitor can suppress the output-dependent delay differences effect. The Chip was designed by using TSMC 0.18μm CMOS mixed model, and the post-simulation results show that the DAC achieves 74.1 and 68.9 dBc SFDR at 1GS/s with 50MHz and 450MHz output frequency, respectively.
Slurry Concentration Detection Theory Based on the Ultrasonic Echo Attenuation
Authors: Li Fu Jin , An Chun Yan
Published: November 2012

Decay theory based on the ultrasonic echo, with ultrasonic sensors measure the concentration of the slurry through the use of the controller to control the ultrasonic transmitter and receiver circuits, this system will be integrated waveform chip MAX038 generate burst, and then after the power amplifier drive ultrasonic transducer transmits ultrasonic, use of the logarithmic amplifier attenuation of the echo signal through the mud interface to reach the receiving transducer in the ultrasonic detector amplification, concentration data processing obtained by the microcontroller.
Modeling and Simulation Research of Hydraulic Cylinder Speed Control System Based on High-Speed On-Off Valve
Authors: Gao Qin He , Guan Wen Liang , Song Hai Zhou , Yang Zhi Yong
Published: November 2012

Application of high-speed on-off valve in the hydraulic cylinder speed control system was researched in this paper. Series and parallel application schemes between high-speed on-off valve and hydraulic cylinder are proposed. Model of high-speed on-off valve and hydraulic circuit were established to carry out simulation. The speed and acceleration curve of hydraulic cylinder were achieved by the means of simulation with Simulink. The simulation curves show that, two application schemes can both control the speed of hydraulic cylinder effectively. Series application scheme can be only applied to small flow hydraulic system; parallel application scheme has wider application.
Performance of Carbide Tools with Micro-Texture on Titanium Alloys Cutting in Dry Conditions
Authors: Chen Chen , Chen Yong Jie , Li Ning , Liu Yang
Published: November 2012

Hard machinability of titanium alloys severely limits its development in the field of aviation. It has been proved that micro-texture has a good effect on friction-reducing in turning under the conditions of Minimum Quantity Lubrication (MQL). In this paper, cutting tool with micro-texture on its rake face is fabricated and then experiments are carried out under the conditions of dry continuous turning titanium alloys. A dynamometer is set under the workpiece to measure three components of the cutting forces and the data is processed by Business software MATLAB. Average coefficient μ is calculated according to the mechanical model. Experimental results show that under the dry conditions, micro-texture plays a role in the specific cutting parameters while losing its role in most cases. Also the reasons which lead to the failure of improving the friction properties are analyzed.
A Novel MPPT Intelligent Multiple Method Based on CVT and Fuzzy Control Applied in PV Power System
Authors: Li Ji Yong , Gong Ren Xi , Feng Zhao He
Published: November 2012

The power available at the output of photovoltaic (PV) cells keeps changing with solar irradiation and ambient temperature because PV cells exhibit a nonlinear current-voltage characteristic. In order to gain maximum power in PV power system, a novel MPPT method combining CVT and fuzzy control was proposed in this paper. The principle of the novel MPPT method was given and the verified experiment was performed at the same time. Experiment results show that the novel MPPT intelligent multiple method have the fast tracking ability in changing weather and more tracking accuracy in stable condition simultaneously.
Multi-Parameter Test System Based on the Microcontroller and Labview
Authors: Xu Shan Zhen , Chen Yun Chi , Wang Cheng
Published: November 2012

It put forward the design scheme of the multi-parameter data acquisition based on the existing sensors and related test equipment in laboratory. The system selected the acceleration and speed signals as the measured parameters. The PC computer was taken as the host computer and the PCI-6014 data acquisition card was used to achieve the data collection, analysis, storage and display of various parameters. At the same time the host computer sent the control signal to SCM. The SCM of AT89S52 was used as the slave computer to receive the control signal from the host computer and give an alarm signal. To achieve the real-time control for the data acquisition, the communication between the host and slave computer was achieved via the RS232 serial communication technology.
Study on the Temperature and Speed Test System
Authors: Zhao Qian , Xu Shan Zhen , Chen Qi , Wang Cheng
Published: November 2012

A kind of multiple parameter data acquisition system was designed based on single-chip microcomputer which can realized the data acquisition of temperature and DC motor speed. The data acquisition system consists of sensor, signal processing circuit, single-chip microcomputer and LED digital tube. The speed signal is acquired by photoelectric sensor, put into the Single-chip microcomputer processed after processed by signal processing circuit, and displayed the value in the digital tubes. The temperature signal is acquired by digital sensor, and the Single-chip microcomputer can read the data directly. Through two independent keyboards, the test system realized the data acquisition and data switch displaying of the multiple parameters.
Preparation of SnS2, SnS2:Cu, SnS Nanocrystals and Assembly of Thin Film Solar Cell with the Novel Structure of FTO/SnS2:Cu/SnS/Sn
Authors: Yao Min , Shi Cheng Wu , Zhang Yan Ru , Li Bing , Tao Li
Published: November 2012

In this paper, SnS2, SnS2:Cu and SnS nanocrystals were prepared by hydrothermal method and the thin film solar cell with the novel structure of FTO/SnS2:Cu/ SnS/Sn was fabricated by dipping-coating technique. The thin film solar cell gave the short circuit photocurrent density of 37.5 μA·cm−2, open circuit voltage of 130 mV, and fill factor of 0.35, corresponding to the photoelectric conversion efficiency of 0.17 %.
Precision Point Design of a Cam Indexing Mechanism
Authors: Borboni Alberto , Aggogeri Francesco , Pellegrini Nicola , Faglia Rodolfo
Published: November 2012

This work regards on the design of a cylindrical cam indexing mechanism with a motion law that passes through a positional precision point. A numerical algorithm is proposed to solve this problem and, particularly, a genetic algorithm. The algorithm and the encoding of the problem are described.
Innovative Modular SMA Actuator
Authors: Borboni Alberto , Aggogeri Francesco , Pellegrini Nicola , Faglia Rodolfo
Published: November 2012

A modular design for a shape memory actuator is proposed. The actuator is able to perform linear movements, while the modularity allows force and/or stroke improvements. Experimental results show how the behavior of the proposed implementation is sufficient for a wide class of problems and can be improved with proper developments.
Design of Current-Model Signal Source of Time Grating with Self-Compensation Technology
Authors: Zheng Fang Yan , Chen Zi Ran , Yang Ji Sen
Published: November 2012

The measurement precision of time grating sensors is influenced by the phase symmetrical characteristic of three-phase exciting signal source. Therefore, a novel current-model exciting signal source with self-compensation technology is presented. In order to obtain high precision phase symmetry in stability, three orthogonal sine signals are generated by direct digital frequency synthesis (DDS) technology with self-checking and self-collection. Experiment results prove that the stability and measurement precision are improved significantly.
Optimization Design of Loader Engine Stents Based on ANSYS
Authors: Wu Yong Hai , Wang Feng
Published: November 2012

Seeking the best layout engine scaffold materials is always the focus of the stent design personnel stent . This object of research in this article is the engine stent of a certain loader. the geometric structure model is created by Solidworks. On this basis, finite element model is created in ANSYS. Structure of stent is optimized topologically by using variable density of topological optimization algorithm in which bracket stiffness is been as the optimization objective and reduce the materials quality is been as the state variables. And stent is modeled secondly by using gotten the most optimal topological model. The stress and deformation of the improved stent of engine increased. But weight of stents is reduced by 8.7%.
Electrodeposition of Ni-Based Coatings with the Addition of CeO2 Nano Particles
Authors: Qu Ning Song
Published: November 2012

In the present study, a new nanocomposite coatings, Ni-CeO2, has been prepared by electrodepositing. The effect of current density on the CeO2 particles included into the deposits, morphology, preferred orientation, wear resistance and high temperature oxidation resistance has been studied. The investigated results demonstrate that the weight percent of particles in the nanocomposite coatings varied with a rise in current density, and the maximum weight percent of CeO2 particles in the coatings is 4.97 wt% obtained at the current density of 1 Adm-2. The paper firstly presents that the high temperature oxidation resistance of nanocomposite coatings is closely related to the current density, at which the nanocomposite coatings were electrodeposited, and the best high temperature oxidation resistance was acquired at the current density of 1 Adm-2
Kinematic Modeling for a 6-DOF Industrial Robot
Authors: Gao Guan Bin , Lu Jian , Zhou Jian Jun
Published: November 2012

The kinematic model of robots is to describe the nonlinear relationship between the displacement of joints and the position and orientation of the end-effector, which is an important part of robotics. Kinematic model has great influence on the robot’s accuracy and motion control. In this paper, we studied the robot’s kinematic modeling methods and analyzed the characteristics and singularity of traditional DH method. By analyzing and comparing the structural characteristics of a 6-DOF industrial robot a MDH method was chosen to establish kinematic model. From the kinematic model the joint coordinate systems, structural parameters and homogeneous transformation matrixes of the robot are obtained. The kinematic model provides a theoretical basis for the robot motion control, calibration and error compensation.
Research on Green Manufacturing of Automotive Enterprises Based on Fuzzy Comprehensive Evaluation Method
Authors: Li Su Hua
Published: November 2012

According to the analysis of the green performance at all stages in the process of green automotive manufacturing, the model of the green evaluation of automotive enterprises as well as the calculation method of it has been proposed in this paper. At the same time, a number of programs proposed by several companies which can meet the green requirements have been also specifically analyzed in this paper so as to obtain the green manufacturing programs that are best suited to the automotive enterprises, which has the practical guiding significance.
Analysis of the Structure and Morphology of Hydroxyapatite Nanopowder Obtained by Sol-Gel and Pirosol Methods
Authors: Rogojan Rodica , Andronescu Ecaterina , Ghitulica Cristina , Birsan Mihaela , Voicu Georgeta , Stoleriu Stefania , Melinescu Alina , Ianculescu Adelina
Published: November 2012

Nano-size hydroxyapatite is the main inorganic component of bone. There is a critical particle size that each property starts to change. Each property can be modified under controlled conditions. Multifunctional materials for applications, one must consider several properties change. Bone properties, are those which dictate the properties of hydroxyapatite, properties to be followed the synthetic materials to be used successfully as implants. Of these mention those related to surface materials, solubility and biocompatibility and their mechanical strength. Depending on the location and functionality of the implant have met some of these properties. The purpose of this study is to develop a synthetic hydroxyapatite at nano scale, using sol-gel and pyrosol method, for its use in medicine
Micro-Drilling of CFRP Plates Using a High-Speed Spindle
Authors: Ogawa Keiji , Nakagawa Heisaburo , Hirogaki Toshiki , Aoyama Eiichi
Published: November 2012

Fundamental characteristics in the micro drilling of carbon fiber reinforced plastic (CFRP) plates are investigated in the present paper. When micro drilling with a high-speed spindle, cutting forces during drilling, such as thrust force and torque, were measured by high resolution dynamometers and drill temperature was monitored by thermography. Comparing the experimental results of CFRP with that of drilling glass fiber-reinforced plastics (GFRP) revealed some unique tendencies. The cutting forces and drill temperature increased drastically. Moreover, drill wear rapidly accelerated. The tool life of CFRP plate drilling is much shorter than that of other plates.
Influences of the Inserted Angle of an Optical Fiber for an Optical Trapping
Authors: Watanabe Nobuyuki , Taguchi Kozo
Published: November 2012

Biological cell could be trapped by a single laser beam from an optical fiber end inserted at an angle to a sample chamber. We have already developed an optical trapping system. A temperature stabilized 1480nm cw diode laser was used as the light source. The fiber end had a hemispherical micro-lens with 5μm radius of curvature for focusing the laser beam. These trapping fibers were inserted into a sample cell at an angle. The microsphere, 10μm diameter particle (refractive index 1.4), could be trapped. We theoretically analyzed the optical forces exerted on a microsphere by laser beams. The optical force on a microsphere divides itself into two components, the force in the beam axial direction of the light and a transverse force. The transverse optical force acted to pull the sphere back. We investigated the relation between the pulling force and the inserted angle of an optical fiber into a sample chamber. The microsphere is trapped at the point where the horizontal directed optical forces are balanced. We theoretically verified that the inserted angle of an optical fiber into a sample chamber was important parameter. It was found that a small inserted angle produced a weak pulling force.
Improvement of Interface Roughness in Platinum/Carbon Multilayers for X-Ray Mirrors
Authors: Kim Jang Woo , Matsuyama Satoshi , Sano Yasuhisa , Yamauchi Kazuto
Published: November 2012

We present a study of the improvement in interface roughness of platinum/carbon multilayers for X-ray mirrors. The X-ray reflectivity of multilayers strongly depends on interface quality. In an effort to reduce the interface roughness caused by crystallization during deposition, carbon doping of platinum was proposed, and its effectiveness was evaluated. We compared 45-nm-thick single-layer platinum to carbon-doped platinum films. The films were deposited on a silicon (100) substrate by dc magnetron sputtering deposition. The surface roughness and X-ray diffraction spectrum of each film were measured by atomic force microscopy and X-ray diffraction, respectively. We concluded that the increase in carbon concentration suppresses the crystallization of platinum and causes the surface roughness to decrease.
The Effect of Cutting Point Swivel Machining by Using Round Tool with Special Chamfer
Authors: Tang Xin Rui , Nakamoto Keiichi , Obata Kazushi , Takeuchi Yoshimi
Published: November 2012

Recently, in accordance with the technical development and miniaturization of the information equipments, the demand of optic elements with high precision and miniaturization is increased. The mold is used in the manufacture of the optic elements. Thus, it is needed to machine the mold with high efficiency and high precision. As the material of mold, hard material including cemented carbide and ceramics is used. However, it is a problem of the occurrence of severe tool wear when hard material is machined. To solve this problem, the cutting point swivel machining by using the diamond tool with special chamfer was proposed, which has the ability to suppress tool wear and to realize ultraprecise machining. It is confirmed that the cutting point swivel machining has the ability to suppress tool wear by the microgrooving experiment of SiC. This study aims at investigating the effect of the cutting point swivel machining, and making clear the relationship between tool rotation speed and tool wear. As a result, it is known that the actual cutting direction can be changed by using the cutting point swivel machining, and that the chipping of tool becomes conspicuous with increasing tool rotation speed.
Edge Sharpening and Surface Modification of PcBN Cutting Tool by Pulsed Laser Grinding
Authors: Suzuki Daisuke , Itoigawa Fumihiro , Kawata Keiich , Suganuma Tetsuro , Nakamura Takashi
Published: November 2012

PcBN cutting tools have excellent characteristics such as high degree of hardness and low chemical reactivity, so they have potential to replace high precision grinding of hardened steel with high precision cutting. PcBN might be more efficient tool material if improvement in formability, and good surface modification can be achieved. In order to solve these problems, Pulsed Laser Grinding (PLG) is applied to a shape cutting edge and to finish a rake face. After processing by the PLG, shaped cutting edges were observed with a scanning electron microscope (SEM) and measured with contact- type profilometer. As a result, cutting edges processed by the PLG are similar or shaper than that by conventional diamond grinding. In addition, as a one of effects of surface modification, The Vickers microhardness of rake faces increases by about 10 present after PLG. On the other hand, according to frictional test with lateral force microscopy, the coefficient of friction of rake face decreases by half of ordinary surface. Depending on these advantages of PLG, high precision turning of hardened steel with 58HRC in hardness by use of the tool processed by PLG can demonstrate good performance rather than a commercial tool with diamond grinding finish.
Soft-Consolidation Abrasives Pneumatic Wheel Technology Oriented to Finishing of High-Hardness Free-Form Surface
Authors: Ji Shi Ming , Zeng Xi , Jing Ming Sheng
Published: November 2012

In order to improve the efficiency of high-hardness laser strengthening mold polishing, especially to the free-form surface, a new precision finishing method based on soft-consolidation abrasives pneumatic wheel is brought forward. The pneumatic wheel is constituded by flexible rubber maxtrix, combined with the robbet control. The abrasives group is bond to the rubber matrix by the polymer binder. In the way, compared with those free abrasives used in other polishing method, the soft-consolidation abrasives can get more stable surpport from nearby polymer to form effective cutting. On the other hand, it is unlike the abrasive of rigid grinding wheel because the flexibility of pneumatic wheel can have self-adaptation according to the changes in local curvature and achieve large scale copying contact between tools and work piece. Combined with the lay elastic system theory and Preston equation and coefficients, the mechanics model of polishing is given. The results of experiment shows the Ra of workpiece can be reached to 0.09um and the efficiency of process can be improved three times more than free abrasive machining. It will show its wild prospects in the process of polishing.
Performance of Wire-Sawing of Glass Assisted by Electro-Chemical Discharge
Authors: Furutani Katsushi , Tomoto Michiaki
Published: November 2012

This paper deals with a combination machining method of slicing with electro-chemical discharge machining (ECDM). Glass and fine ceramics are hard to machine, and cracks are generated on their surface during cutting and grinding because of their brittleness and hardness. ECDM has been studied for machining such insulating materials. The authors have proposed a deposition method of WC layer by electrical discharge machining (EDM) with a compressed WC-Co powder as an electrode. The improvement of removal rate is expected by combining wire-sawing with ECDM. A silica glass rod was cut with a saw wire with the WC layer. The removal rate of the combination machining is larger than that of individual use of ECDM or wire sawing. The groove width by wire sawing was smaller than the others. Cracks were seldom observed on the bottom and side walls of the groove. Providing the fresh working fluid also assisted to decrease the cracks. The synergy of wire-sawing with ECDM was obtained.
Detection of Surfaces and Edges in Large Point-Clouds Using Region-Growing on Spherical Space
Authors: Masuda Hiroshi , Matsuoka Ryo , Abe Yuji
Published: November 2012

Engineering facilities can be digitized as large-scale point-clouds by using the state-of-art mid-range laser scanners. For utilizing captured data in CAD systems, it is important to convert point-clouds to parametric surfaces. In this paper, we describe a method for robustly extract cylindrical faces and planar faces. Edges and silhouette lines have to be generated to construct bounded faces, but unfortunately points on silhouettes are very noisy in the case of mid-range laser scanners. Our method applies region-growing method on spherical space and improves the robustness. In addition, we enhance the region-growing so that surface regions can be propagated to disconnect points using multiple overlapping point-clouds.
Sensor-Less Tool Fracture Detection Applying Disturbance Observer Theory
Authors: Koike Ryo , Kakinuma Yasuhiro , Aoyama Tojiro
Published: November 2012

Detection of a tool fracture is necessary to ensure cutting accuracy and to avoid a tool breakage because tool fracture is one of the significant prediction signals of the tool breakage. For monitoring the tool condition, generally additional sensors are used. However using these sensors causes high cost and increase of failure rate. In this paper, a novel sensor-less detection method of tool fracture in drilling process is proposed on the basis of a disturbance observer theory. It is applied to the x-y stage of the machine tool. The proposed method requires no external sensor because it uses only the servo information of the spindle control system. Since structures of normal drills with two floats are symmetrical with respect to a point, theoretically the cutting force in the x and y directions does not work. When the drill is fractured, its structure becomes asymmetry so that unbalanced forces would exert in the x and y directions at intervals of the spindle speed. Therefore, it is possible to detect a tool fracture by the frequency analysis of estimated disturbance force with a wavelet transform. The experimental results show that the proposed method is available for detection of the small tool fracture effectively.
Analysis of Kinematic Motion Deviations of Machining Centers with Rotational Axis Based on Geometric Tolerances
Authors: Sugimura Nobuhiro , Thasana Wiroj , Iwamura Koji , Tanimizu Yoshitaka
Published: November 2012

Much progress has been made in the machine tool technologies, aimed at improving the performances of the machine tools from various viewpoints, such as accuracy, reliability, produc-tivity, and flexibility. The machining accuracy is one of the most important characteristics of the machine tools. From the viewpoints of the design and the manufacturing of the machine tools and their components, one of the important issues is to clarify the relationships between the kinematic motion deviations of the machine tools and the geometric tolerances of the components, such as the guide ways and the bearings. The objective of the present research is to establish mathematical models representing the kinematic motion deviations of the machine tools, on the basis of the geo-metric tolerances of the components, and to apply the models to analysis of the kinematic motion deviations.
Precise Positioning of an Air Bearing Lead Screw Stage by Semi-Closed Loop Control
Authors: Fukuda Makoto , Niwase Yasushi
Published: November 2012

An air bearing lead screw, whose nuts are levitated from the screw threads, has a great advantage of accurately transforming rotational motion to linear motion due to no friction, no backlash and no hysteresis. Therefor precise linear motion can be provided by precise rotational motion which can be obtained by a precise rotary encoder and a motor controller. We developed a positioning controller with servo sampling rate of 10 kHz that employed FPGA (Field Programmable Gate Array) and applied it to positioning of an air bearing stage. The stage consists of an air bearing lead screw and an air bearing linear guide. A rotary encoder, whose resolution has 225000 pulses per rotation, was directly mounted on an axis of the lead screw. This paper describes the positioning performance of the stage by the use of this semi-closed loop control, such as the resolution of less than 10 nm, the linearity over the long stroke.
A New Process to Fabricate Three Dimensional Ordered Nano Dot Array Structures by Nano Plastic Forming and Dewetting
Authors: Li Zhen Xing , Yamanaka Akinori , Yoshino Masahiko
Published: November 2012

Three dimensional (3D) nano/quantum dot array structures have attracted more and more attention due to their broad applications. A new fabrication method of multilayer ordered nano dot array with low cost and high throughput is developed in this paper. This process is combination of Top-down and Bottom-up approaches: Nano Plastic Forming (NPF) patterning of metal layer coated on the substrate as Top-down approach and self-organization by dewetting as Bottom-up approach. Effects of process conditions on 3D nano-dot array formation are studied experimentally. Regularity and uniformity of first layer nano-dot array is transferred to the second layer nano-dots by optimizing thickness of the spacer layer and Au coating layer. Multilayer ordered nano dot array structures with good alignment are obtained by repeating coating and annealing processes.
Development of Wire-Connected Mechanism for Precise Positioning
Authors: Shinoda Masahiro , Hirata Shinnosuke , Aoyama Hisayuki
Published: November 2012

Micro/nano positioning is one of important techniques to operate bio-cell and micro assembly. For realizing the precise positioning, the various piezo-driven stages have been already proposed and micro/nano scale resolution has been achieved. However, it is pointed out that the existing precision positioning tools are too large compared to operating area. Their devices are too difficult to combine other devices and use in tight environment like under microscope. In this paper, a precise positioning method with wire connected mechanism under microscope is proposed. The proposed positioning system is simply composed actuators including piezoelectric element and super extra-fine wires. By applying wire connected mechanism, the saving of larger work environment compared to traditional devices is hoped.
Quantitative Evaluation Method for Damping Capacity of Linear Rolling Bearings for Feed Drive Mechanisms
Authors: Sakai Yasunori , Tsutsumi Masaomi
Published: November 2012

The vibration damping of guide ways is an important factor in the design of feed drive mechanisms for machine tools. Linear rolling bearings are often used as guide ways because of their low friction. However, there are no quantitative evaluation methods for its damping. Thus, this paper describes a quantitative estimation method for the stiffness and damping capacity of a linear roller guide through an experiment and a mathematical model. The stiffness and damping coefficient of the linear roller guide are identified through the frequency resonance function and mathematical model of the feed drive mechanism. It is shown that a lubricant film can effectively increase the stiffness and damping capacity of the linear roller guide.
Development of a Lens Driving Maglev Actuator for Laser Beam Off-Axis Cutting and Deep Piercing
Authors: He Dong Jue , Shinshi Tadahiko , Nakai Takahiro
Published: November 2012

In laser beam cutting and laser piercing process, the machining speed and quality are very sensitive to the flow of assist gas and laser beam focusing position. In order not only to improve the cutting speed and the removal capability of the molten material and to save the consumption of the gas flow in laser beam cutting, but also to realize high speed piercing of high aspect-ratio holes, a magnetic-levitated (maglev) lens driving actuator was proposed and fabricated. The actuator can drive the lens to achieve real-time positioning control of the relative radial displacement between the lens axis and the assist gas jet nozzle axis (off-axis control) in radial directions in a range of ±1mm within 1.5 μm of tracking error and bandwidths more than 150Hz, and to achieve real-time positioning control of laser beam focusing point in axial direction in a range of ±5mm within 3 μm of tracking error and bandwidth more than 100Hz.
Development of a Cutting Tool with Micro Built-In Thermocouples - Characteristic of the Micro Cu/Ni Thermocouples Fabricated by Electroless Plating and Electro Plating
Authors: Harashita Junichi , Tomoda Yuji , Shinozuka Jun
Published: November 2012

This study has devised a tool insert with micro built-in thermocouples in order to establish a cutting-temperature measuring method for practical use. This tool insert possesses seven pairs of micro Cu/Ni film thermocouple near the cutting edge on the rake face. In this study, Cu film and Ni film were deposited in the micro grooves corresponding to a circuit pattern of the micro thermocouple by means of electroless plating and electroplating. This paper shows the results of the investigation concerning the electrical properties of the micro Cu/Ni film thermocouples. The influence of the current density in electroplating on the electrical resistivity of the films was examined. The characteristic of the Seebeck property of the micro Cu/Ni film thermocouple was investigated in a temperature difference of up to 600 K with a heating apparatus developed. The Seebeck coefficient of the micro Cu/Ni film thermocouple was smaller by 28 % than that of a Cu/Ni wire thermocouple. The result implies that the degradation in the Seebeck property of the micro Cu/Ni film thermocouple derives from an existence of an impurity between Cu film and Ni film in the hot junction.