bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Burrs Detection of Parts Surface Based on Threshold Segmentation
Authors: Zhang Yi , Chen Xiao Rong , Li Hao Lin , Tan Fu Sheng , Yan Jun Fan
Published: August 2014

Mental cutting process, a widespread process in the machining, which can produce the maximum number of burrs. Burr detection and deburring are crucially important to safe reliability of parts. In order to avoid the effects of subjective factors effectively, and improve the production efficiency and production automation, we introduced the machine vision technique. According to the universal burrs produced in the cutting process, this paper principally studied the image segmentation, burrs feature extraction, the improvement of adaptability based on digital image processing. The authors conclude that the algorithm applied in this paper can detect the burrs information effectively, laid a solid foundation for automatic polishing, with the certain practical value.
Study on Pre-Mixed Micro Abrasive Water Jet Machining System
Authors: Liu Zeng Wen , Liu R.Y.
Published: August 2014

This paper conducts a study on a pre-mixed micro abrasive water jet machining system. A new kind of abrasive mixing tank and the jet system are designed and tapped for the pre-mixed micro abrasive water jet machining system. The performances of the pre-mixed micro AWJ machining system are tested, and some polishing experiments are conducted for hard-brittle materials such as silicon nitride. The results show the feasibility and the advantage of the pre-mixed micro abrasive water jet machining system for polishing hard-brittle materials.
A High Precision and Convenient Method to Analyze the Mechanics of Scissor Lift Platform under the Action of Combined Loads
Authors: Qu Fei Peng , Xue Yuan
Published: August 2014

Scissor lift platform had lots of kinematic pairs and the mechanics relations between them were complex. So mechanics analysis became the focus by researchers. The mechanical model of scissor lift platform under the action of combined loads was built in the paper. The calculation formula of nodal force of scissor transmission unit was given used the transfer matrix method. The calculation formulas of drive units were given on the virtual work principle. Also the calculation method of nodal forces of drive units was given. How the different distributions of drive unit influence on the nodal force was analyzed. The drive units’s position optimization method was given in this paper. In order to verify the reliability of this calculation method, an calculation example of typical structure was given. The calculation results given by the method in this paper was identical with the result given by finite element method. The conclusions obtained could serve as theoretical guidance and reference for mechanical analysis and optimal design of scissor transmission mechanism.
A Thin Cloud Removal Method for Optical Image Based on Improved Homomorphism Filtering
Authors: Yu Guang , Sun Wen Bang , Liu Gang , Zhou Mai Yu
Published: August 2014

Optical remote image is affected by thin cloud inevitably, which debases image definition. Traditional homomorphism filtering frequently used in thin cloud removing has affect on the cloud in low frequency region, but is not effective for those in high frequency region. An improved homomorphism filtering method is proposed on the basis of statistical characters of image information. Instead of the filtering in frequency field, it isolates the low frequency component of the image representing cloud information with calculating neighborhood average in spatial field. Then, the filtered image is enhanced based on rough set. The experiment results show that the proposed method compared to traditional methods can obtain good results and performs faster.
Design of a 0.7~2.6GHz Wideband Power Amplifier in 0.18-μm CMOS Process
Authors: Yu Zhou , Fan Xiang Ning , Hua Zai Jun , Xu Chen
Published: August 2014

A power amplifier (PA) for multi-mode multi-standard transceiver which is implemented in a TSMC 0.18μm process is presented. The proposed PA uses matching compensation, lossy matching network and negative feedback technique to improve bandwidth. To achieve the linearity performance, the two-stage PA operates in Class-A regime. Simulation results show that the power amplifier achieves maximum output power of more than 24dBm in 0.7~2.6GHz. The output P1dB of the PA is larger than 22dBm. The simulated power gain is more than 27dB. The S11 is less than-10dB and the S22 is under-5dB.
Design of Microcontroller Standard SPI Interface
Authors: Li Li Li , He Jing Yu , Zhao Yong Peng , Yang Jian Hong
Published: August 2014

This paper describes a design of high-speed and reusable SPI interface model which is used for Microcontroller. The SPI interface is designed by very simple but universally useful method, used a FIFO to improve transmission speed and supported data serial input and parallel output which other interface didn’t mentioned. The paper analyses the function of every module of SPI interface and standard 8051 microcontroller interface communication protocol, describes the design project of implement SPI logical function. After testbench and FPGA verification, the results indicate that the microcontroller SPI interface function and performance are all achieve design target, many communication tests indicate the design is reliable in performance and more universal.
SVM-Based Credit Rating and Feature Selection
Authors: Qin Yu Qiang , Qi Yu Dong , Ying Hui
Published: August 2014

The assessment of risk of default on credit is important for financial institutions. Logistic regression and discriminant analysis are techniques traditionally used in credit rating for determining likelihood to default based on consumer application and credit reference agency data. We test support vector machines (SVM) against these traditional methods on a large credit card database. We find that they are competitive and can be used as the basis of a feature selection method to discover those features that are most significant in determining risk of default.
Study on the Value Management of Forestry Intangible Assets in the Era of Knowledge Economy
Authors: Zhou Zhao , Zhang Jun Mei , Wang Shu Hui , Chen Rui , Zhong Wen Wen
Published: August 2014

In the era ofthe knowledge economy, the accounting priority has shifted from tangible assets to intangible assets. The knowledge economy-based intangible assets is gradually emerging as the main impetus for determining the forthcoming cash flow and market value. This paper takes the stocks listed in Shenzhen Securities Exchange as the study object, conducts empiricalstudy and analysis based on the sampling data, including 2008-2010 pershare intangible assets,per share returns, per share net assets after deducting intangible assets and share price,describes the disclosure of intangible assets of such listed companies as Jilin Forest Industry,Zhongfu Industrial, Yihua Timber Industry, Fenglin Group and Palm Landscape and inspects the value relevance of intangible assets. Accordingly, this paper proposes to consolidate the value management of intangible assets of the forestry enterprises and improve their core competítíveness.
Grid Material Supplier Selection Based on Entropy Weight Correction from Perspective of Low Carbon
Authors: Jia Zheng Yuan , He Bin
Published: August 2014

Supplier management is an important part of supply chain management, combined with the feature of the power industry, the paper design supplier comprehensive evaluation system of power grid enterprises, and put forward comprehensive green degree into supplier evaluation index system to conform to the national grid company production requirements. Firstly, according to the index system, the analytic hierarchy process evaluation method to draw the initial weights, secondly, the modification of entropy weight method to reduce the subjective factor influence on the evaluation results by AHP , finally, an example is given to demonstrate the feasibility of the evaluation index system for the power grid enterprise, it aslo provides a theoretical basis for decision-makers during the vendor selection.
Galvanic-Cell-Based Synthesis and Photovoltaic Performance of ZnO-CdS Core-Shell Nanorod Arrays for Quantum Dots Sensitized Solar Cells
Authors: Chi Le Ha , Long Pham Duy , Chung Hoang Vu , Phuong Do Thi , Mai Do Xuan , Oanh Nguyen Thi Tu , Lien Thach Thi Dao , Trung Le Van
Published: August 2014

Zinc oxide (ZnO) is recognized as one of the most attractive metal oxides because of its direct wide band gap (3.37 eV) and large exciton binding energy (60 meV), which make it promising for various applications in solar cells, gas sensors, photocatalysis and so on. Here, we report a facile synthesis to grow well-aligned ZnO nanorod arrays on SnO2: F (FTO) glass substrates without the ZnO seed layer using a Galvanic-cell-based method at low temperature (<100°C). CdS quantum dot thin films were then deposited on the nanorod arrays in turn by an effective successive ionic layer adsorption and reaction (SILAR) process to form a ZnO/CdS core-shell structure electrode. Structural, morphological and optical properties of the ZnO/CdS nanorod heterojunctions were investigated. The results indicate that CdS quantum dot thin films were uniformly deposited on the ZnO nanorods and the thickness of the CdS shell can be controlled by varying the number of the adsorption and reaction cycles. The number of quantum dots layers affects on photovoltaic performance of the ZnO/CdS core-shell nanorod arrays has been investigated as photoanodes in quantum dots sensitized solar cells.
Research for Photoelectric Property of SnO2 Doped Sb
Authors: You Xin , Miao Feng , Huang Yi , Zhang Chuan Wu
Published: August 2014

based on Density Functional Theory, we investigated the electronic structures and the optical properties of Sb doped SnO2 with density of 12.5%.including band structure ,the density of state (dos),dielectric function and optical absorption spectrum. The results show that Fermi level access valence band gradually with the doped density. And this can attributed to the increased folded state. Which have enhanced the electrical and metal property of material ;The peaks of absorption Spectrum and dielectric spectrum correspond, Optical absorption edge decrease and the absorption peaks show blue shift.
Modification of Expandable Graphite and Adsorption for Methyl Orange
Authors: Yang Liu , Liu Hui , Deng Qin , Zhou Yan Zi , Zhang Yan Zong
Published: August 2014

Results of preparing expandable graphite through Microwave Expansion method with the material of expandable graphite made through the Chemical Oxidation process show that in the temperature range of 700°C~900°C, the volume of expandable graphite will bigger with the rise of temperature, reaching the maximum 203 ml/g at the temperature of 900°C. The expandable graphite of 900°C can be modified in 0.5M hydrochloric acid; at the temperature of 40°C and 6h later, decolourization ratio of methyl orange will reach 95%. If the graphite is modified in concentrated nitric acid with the temperature of 50°C for 6 hours, the decolourization rate will be 96%. In terms of cost, it is more economical to modify expandable graphite in hydrochloric acid.
Bonding Properties of Poplar Plywood with High Moisture Content Veneer
Authors: Qiao Jian Zheng
Published: August 2014

The poplar is largest plantation tree species of in China. However, poplar veneer is easily broken when subjected to drying for plywood. This work presents an orthogonal test to reveal the key technological parameters of poplar veneer with high moisture content (MC) on the bonding properties. The results showed that, veneer MC has a significant effect on internal bond (IB) and MC of obtained plywood, but has a light effect on the content of released formaldehyde. Resin content has a significant effect on IB, MC and content of released formaldehyde. Hot-press time has a significant effect on content of released formaldehyde; but has a light effect on MC and IB. The obtained optimal technological parameters of poplar veneer with high moisture content is, veneer MC of 26%, resin content of 11%, and hot-press time of 200s.
Core of the Structural Characteristic of Natural Zeolite and its Catalytic Activity in the Aromatization of Light-Molecular Paraffin
Authors: Gulzira Vasilina , Raisa Moisa , Zhaksyntay Kayrbekov , Elmira Yermoldina
Published: August 2014

The porous structure of Semeytau natural zeolite field, catalysts on its basis, and their catalytic activity in the course of aromatization of n-octane has been investigated. Higher activity of Ni, the Zn sample containing catalyst is defined by formation by more developed specific surface and porous structure.
Synthesis of Rigid-Body Guidance Mechanism with Path and Pose Generation Independently
Authors: Liu Jing Shuai , Lin Song
Published: August 2014

This paper proposes a practical method for the synthesis of rigid-body guidance mechanism by dividing the guidance task into path and pose generation independently. As a first step, based on the mechanism combination principle, a basic four-bar mechanism for path generation is synthesized and a binary-link is combined to the mechanism for achieving the execute link’s poses, then the potential kinematic chain with ability to realize the desired coupler poses is selected from all of the combination possibilities. And then a strategy by fixing a Cam to the basic four-bar mechanism to control the linkage poses is also proposed. Finally, the Cam’s profile is synthesized and the combined cam-link mechanism is able to guide the coupler through all desired linkage positions. One example is presented to validate the proposed guidance mechanism synthesis method.
The Effects of Injection Timing on BDF in an IDI Diesel Engine
Authors: Kim Eun Sung , Choi Seung Hun
Published: August 2014

Biodiesel fuel (BDF) can be effectively used as an alternative fuel in diesel engines. The BD, however, may affect performance and exhaust emissions of the diesel engine because it's physical and chemical properties, such as viscosity, compressibility and so on, are different from the diesel fuel. To investigate effects of an injection timing on characteristics of performance and exhaust emissions with the BDF in an IDI (Indirect injection) diesel engine, this research applied the BDF derived from soybean oil in this study. The engine was operated with six different injection timings from TDC to BTDC 12°CA and six different loads at engine speeds of 1500 and 2000 rpm. In less then the BDF 20, the diesel engine showed the similar trend compare to the diesel fuel. But, the best injection timing with the BD 50 was 2°CA retarded compare to the diesel fuel.
Wear Behaviour of Stellite 6 Coatings Produced on an Austenitic Stainless Steel Substrate by Laser Cladding Using Two Different Heat Inputs
Authors: Kusmoko Alain , Dunne Druce P. , Li Hui Jun
Published: August 2014

Stellite 6 was deposited by laser cladding on an austenitic stainless steel substrate (ASS) with energy inputs of 1 kW (ASS 1) and 1.8 kW (ASS 1.8). The chemical compositions and microstructures of these coatings were characterized by atomic absorption spectroscopy, optical microscopy and scanning electron microscopy. The microhardness of the coatings was measured and the wear mechanism of the coatings was assessed using a pin-on-plate (reciprocating) wear testing machine. The results showed less cracking and pore development for Stellite 6 coatings applied to the austenitic stainless steel substrate with the lower heat input (ASS 1). Further, the Stellite coating for ASS 1 was significantly harder than that obtained for ASS 1.8. The wear test results showed that the weight loss for ASS 1 was much lower than for ASS 1.8. It is concluded that the lower hardness of the coating for ASS 1.8, together with the softer underlying substrate structure, markedly reduced the wear resistance of the Stellite 6 coating.
Design, Fabrication and Evaluation of a Novel Electro Thermal Micro-Gripper for Handling of Head Gimbal Assembly
Authors: Pimpin Alongkorn , Anuchitworawong Thanapon , Jandabao Nirun , Saengchote Samach , Ratanasumawong Chanat , Srituravanich Werayut
Published: August 2014

A development of a novel electro thermal micro-gripper for handling of Head Gimbal Assembly (HGA) is an ultimate goal of this study. The scope of this study covers a design, fabrication and performance evaluation of the electro thermal micro-gripper. ANSYS software was used to examine the magnitude of tip displacement, exerting force and induced stress to investigate the mechanism’s viability for handling of HGA. Electroplating of nickel was employed to construct the micro-gripper’s mechanisms with three different sizes, and their displacement and exerting force were then examined. From the experiments, each mechanism deflected between 100 to 220 μm while the exerting force was over 200 mN at 25oC above room temperature. Therefore, the results suggested that the new electro thermal micro-grippers are viable for the HGA handling application.
Electrical Energy Conservation in Engineering Industry: A Case Study
Authors: Pahariya Yogesh , Saxena Rakesh
Published: August 2014

Energy efficiency is extremely important to all organisations, especially those that are energy intensive. Detailed studies to establish, and investigate, energy balances for specific plant departments or items of process equipment have been carried out. The energy audit of the industry (Indo-German Tool Room, Indore) has been done. It has been concluded that total energy saving potential of 1,28,560 KWH per year is possible by implementing the recommendations. Hence achievable saving is 13.85% of total annual electricity consumption. The total savings Rs.7,71,360/- per year with initial investment of Rs.12,79,000/-.
Weld Bead Tracking Control of a Magnetic Wheel Wall Climbing Robot Using a Laser-Vision System
Authors: Eiammanussakul Trinnachoke , Taoprayoon Jirawut , Sangveraphunsiri Viboon
Published: August 2014

Magnetic wheel wall climbing robots are used in inspection of weld bead on large steel tanks. This research aims to develop the robot and tracking control algorithm to be more suitable for the inspection process. A laser-vision system was added on the robot to provide accurate weld bead detection. The simulation of the robot tracking along a weld bead by using nonlinear controller is demonstrated the effectiveness of the tracking control system.
A μP-μC-FPGA Synergy Controller for a Linear Delta Robot
Authors: Phanatamporn Kitithorn , Chancharoen Ratchatin
Published: August 2014

The paper proposes a novel of fully integrated microprocessor (μP), microcontroller (μC) and field programmable gate array (FPGA) robot controller that combines their processing power to fully control all functions of a linear Delta robot. The μP computes the heavy floating point Mathematics including the control law and all robot kinematics at 1 kHz rate while FPGA processes all digital signals from/to the digital sensors and actuators in parallel. At the same time, the μC interfaces with analog I/O and personal computer and passes the signals to the μP via FPGA. The proposed controller is effectively used to control a robot. The experimental results demonstrate the performance of the proposed controller.
Design Morphological Changing All-Terrain-Rover and Optimizing with Genetic Algorithm for Enhancing Mobility
Authors: Kim In Ho , Lee Jae Seong , Jeong Woo Young , Kim Jang Hyun , Yang Hyun Seok
Published: August 2014

This paper proposes a design of morphological changing all-terrain-rover as new concept of hybrid-type mobile robot for enhancing mobility. Mobility evaluation is performed by mechanical theories, and its calculating methods are used for simulations. A feasibility of suggested design of all-terrain-rover is investigated by simulation. After verifying feasibility, this paper applies a PD control with the genetic algorithm as optimizing gains for enhancing mobility. The mobility is able to verify by fitness value from simulation results, and it shows that proposed rover can overcome a mobility limitation of former designed rovers.
A Low-Cost Stereo Vision System for Real-Time Pose Estimation and its Application for Robot Tracking
Authors: Sangveraphunsiri Viboon , Bamrungthai Pongsakon
Published: August 2014

In this paper, a 3-D pose estimation system by using stereo vision with low-cost devices is presented. It is developed as a base system for application development. Two webcams and a planar target with circular markers are used to reduce development cost and computational complexity. To avoid correspondence search problem, user has to select regions of interest (ROI’s) of each marker on the two images in the same sequence before starting the 3-D reconstruction process. Linear triangulation method is applied for 3-D position calculation of each marker. These positions and the positions of the markers referenced in the planar target coordinate frame are used for pose estimation by using least-squares fitting algorithm to obtain the position and orientation of the planar target. The system can be applied for robot tracking as shown in the experiments. The experimental results validate the system’s ability to estimate object pose in real-time with minimum system frequency of 25 Hz.
A Study on Mobile Gait Rehabilitation Training Robots
Authors: Eom Su Hong , Lee Won Young , Jang Mun Suck , Lee Eung Hyuk
Published: August 2014

The falling off of body functions occurs gait disturbances as the human body is aged. Rehabilitation training is needed for overcoming such gait disturbances and the training can be achieved through repetitive training. Recent robot-assisted rehabilitation training has been usually performed in indoors and training speed is to be passively selected. Thus, in this study a training method that implements mobile gait rehabilitation training and varies training speed intellectually is proposed. The proposed method estimates gait intentions and information in training subjects and that is used in determining training speed.
Experiment of the State Variable Feedback for a Quadrotor
Authors: Faramee Veeravat , Sangveraphunsiri Viboon
Published: August 2014

This work is the design of the robust attitude stabilization of a quadrotor. The dynamics model of the quadrotor is normally non-linear and it is difficult to obtain an accurate dynamic model. The linearized model is obtained based on data from experiments. The Multiple Input Multiple Output (MIMO) state variable feedback control is implemented to stabilize the system. The dynamic model based on approximated torques (roll, pitch, and yaw) as inputs and the dynamic model based on rotational speeds of the four rotors are used for design the controller. The experimental results from both dynamic model has very similar characteristic and perform much better than the conventional controller.
Study on Dynamic Characteristics of DC Valve in Electro-Hydraulic System Using CFD Simulation
Authors: Junchangpood Aphaiwong
Published: August 2014

The development of an intelligence control system has presently been widely studied for application in areas of automation industries, especially an electro-hydraulic system (EHS). Usually, it has the position, force and speed controls which are sensitive to change in the system parameters. Hence, a multi-input multi-output (MIMO) fuzzy controller has recently been proposed to control those parameters in a complex system. However, a mathematical model of the EHS which included the dynamic parameters has not yet been clarified. The objective of this paper is to analyze numerically the dynamic characteristics of the directional control valve (DCV) and also the flow behaviors in the electro-hydraulic system control. The spool displacements of 4/3 hydraulic closed center DCV and flow-pressure coefficient were simulated with the computational fluid dynamics (CFD). Furthermore, this paper presents CFD results, which explain the flow behaviors related with the dynamic characteristics of flow-pressure coefficient. The simulation results show that those coefficients show non-linear correlation with the opening spool displacements.
Gain-Scheduled Control Approach by Logarithm Transformation for Electrical Vehicle Traction Force Control
Authors: Young Jieh Shian , Lin Yu Bang , Chen Kuan Jie , Chen Po Ting
Published: August 2014

This paper proposes an approach by logarithm to evaluating the electrical vehicle traction force control directly instead of the slip ratio measurements. Utilizing the built character database of the driven motor, or so-called current-RPM-torque database, a gain-scheduled approach by logarithm transformation is developed to provide the appropriate traction force while one traction wheel of the vehicle is traveling into different road surface. An illustrated simulation with a scenario close to real situation is also given to show the feasibility to evaluate and control the traction force through the database of the motor.
Evaluation of Deadband Effect in Steer-by-Wire Force Feedback System by Using Driving Simulator
Authors: Noomwongs Nuksit , Chantranuwathana Sunhapos
Published: August 2014

This paper presents an evaluation of dead band in force feedback which affects on driving precision with Steer-by-Wire System by using Driving Simulator. Dead band is considered as a zero zone of a relation between Force feedback torque and hand wheel angle. Experimental was designed to focus on dead band size from 0 to ±10 degrees of Force feedback model. The result has shown that the driver has the best driving precision with dead band size of ±4 to ±6 degrees.
A New Stator Flux Estimation Method for Direct Torque Control of Electrical Excitation Flux-Switching Generator
Authors: Wang Yu , Deng Zhi Quan
Published: August 2014

The electrical excitation flux-switching (EEFS) machine, which exhibits advantages including high reliability, good flux regulation capability, bipolar flux linkage and sinusoidal back-EMF, is suitable for use as a generator in DC power systems. In this paper, a direct power control (DPC) scheme is investigated for voltage regulation of the EEFS generator in order to improve the dynamic performance. However, the stator flux estimation accuracy will affect torque control quality. Hence, a simple and practical stator flux estimation method, which only contains a second-order low pass (LP) filter, a high pass (HP) filter and a simple coordinate transformation module, is proposed for the DPC scheme of the EEFS generator. In this estimation method, the HP filter can completely filter out the DC drift in the back-EMF, and the leading phase produced by the second-order LP filter and HP filter can be compensated by the coordinate transformation module. Hence, at any synchronous angular frequency, the amplitude-frequency and phase frequency characteristics of the new estimation method are same as those of the pure integrator, while DC gain of this method is zero. The DPC scheme of the EEFS generator using this estimation method exhibits good dynamic performance, which is verified by experimental results.
Prediction the Springback in Air-Bending Process Using Neural Network Metamodel
Authors: Abu Khadra Fayiz Y. , Abu Qudiri Jaber E. , Hussein H.M.A.
Published: August 2014

To eliminate geometric deviations of sheet metal subjected to an air-bending process from the geometry required by the designer, it is necessary to predict the accurate value of the springback. Springback is the elastic deformation observed upon removal of the load during a bending process. In order to predict the springback amount, a multidimensional function should be approximated. In this paper, a neural network metamodel (NNM) based on the back propagation algorithm is introduced to predict the springback value. A verified nonlinear finite element model is developed to generate NNM training data. To select the training data for the NNM, computer generated D-optimal designs are utilized. The NNM developed model in this research can be used in determination of the springback value in sheet metal bending.
Improved SPIHT Algorithm for Texture Image Compression
Authors: Cui Bao Xia , Wu Yun Ze
Published: August 2014

Aiming at the problems of complicated convolution process of traditional wavelet transform and the unsatisfied effect of SPIHT algorithm for texture image compression, an improved SPIHT algorithm for texture image compression is proposed. At first, the texture image is decomposed into N order with the help of the lifting wavelet and the first-order high frequency sub-bands are decomposed into N-1 order by the lifting wavelet, and then the wavelet coefficients are encoded by the improved SPIHT algorithm. The improved SPIHT algorithm improved the process method of the wavelet coefficients in the low-frequency sub-bands and the detection method of some important coefficient in the L collection of the original SPIHT algorithm. Experiments show that the improved algorithm can retain the texture information of texture image more effectively and the quality of reconstructed image and peak signal to noise ratio are better than the original algorithm at the same rate. The effect is better especially at low rate, so the improved algorithm is an efficient compression method for texture image.
A New Analytical Approach to Estimate Fading in Mobile Communication System Design
Authors: Mandal Nasiba , Bagchi Tapan P.
Published: August 2014

This paperprovides a novel analytical platform for evaluating theessential second order statistical boundaries for fading in mobile communication for average fade duration (AFD) and levelcrossing rate (LCR) of Rayleigh, Rician and Nakagami fading channels. We derive new expressions for average LCR and AFD. We then model and computationally simulate the proposed method for Rayleigh, Rician and Nakagami channels and separately calculate the LCR and AFD for each channel by this approach. Simulated results obtained for all three channels show that the values of LCR and AFD calculated by using the proposed approach are much closer to actual simulated values than what conventional theoretical formulas deliver.
The New Rolling Mill Gearbox Concept Design
Authors: Rattanachan Kittiphat
Published: August 2014

Gear design is a state of art in mechanical design topic. In this paper, the systematic gear design concept was used to design the double output shaft gearbox for rolling mill, the aim to reduce cost of production. The design process starts from receive the requirement data, elaborate the data to the design specification. Make a conceptual design, embodiment design or preliminary design and finally detailed design. The all design methodology has suggested systematic decision-making procedures for early stages of the design. The design result is leading to change from the traditional two stage gearbox into the single stage gearbox ratios 1:2.3.
Evaluating the III-Posedness of Inverse Problem to Size Flaws from Eddy Current NDT Signals Obtained with an Absolute Type Probe
Authors: Yusa Noritaka , Shishido Hiroki , Hashizume Hidetoshi
Published: August 2014

This study discusses the applicability of eddy current testing to the non-destructive evaluation of the depth of a flaw. Three-dimensional finite element simulations are carried out to calculate eddy current signals due to a flaw, and subsequent calculations correlate the difference between signals due to two flaws with the difference between the depths of the flaws. Standard deviation of the difference between the depths of the flaws is used to discuss the ill-posedness of the problem. A flaw is modeled as a sufficiently long rectangular region with a constant width and uniform electrical conductivity; an absolute pancake probe is considered. This study reveals that lift-off and coil diameter do not have a large effect on the ill-posedness, which supports that it is reasonable to decide parameters in actual inspections so that signal-to-noise ratio is maximized. The results obtained also indicate the difficulty in evaluating the depth of a flaw deeper than 1 mm using the signals obtained using an absolute pancake probe.
Comparative Study on Wear Particle Colour Classifications Using Various Machine Learning Algorithms
Authors: Nunthavarawong Peerawatt
Published: August 2014

Wear particle assessment is one of state-of-the-art in used lubricant analyses. There are three categories, i.e. shape analysis, surface texture analysis, and particle colour analysis. Especially, an analysis of wear particle colour can be induced to identify the material type from the worn surface when surface failures of component occurred in the most commonly used lubricants. The quantification of wear particle colours is essential, which is readily extracted by the image processing. However, the colours of wear particles are often unrecognised by visual examination of the human, although these are probably indicated via RGB colours by personal computer. This article therefore aims to determine the quantitative colour descriptors of wear particles, and to find out the suitable method to classify the particle colour. In present work, the colours of wear particle images were separated with combined HSI and L*a*b* colour models, and were then classified by using machine learning algorithms as a decision-making tool. These tools consist of the Bayesian classifiers, Tree classifiers, Rule classifiers, Lazy classifiers, Meta-learning classifiers, and Function classifiers. By comparing in their tools, the function classifier tool was performed to accurately distinguish the heated metals, steel particles, dark and red oxides, and copper alloys, resulting in more reliable examination than that of the other tools.
A Study of a Single-Period Model for the Parallel Fleet Replacement Problem
Authors: Laksuwong E. , Pannakkong W. , Parthanadee Parthana , Buddhakulsomsiri Jirachai
Published: August 2014

This paper presents a new approach for the parallel fleet replacement problem. The problem involves determining an optimal replacement schedule for a fleet of vehicles that results in minimal total cost of owning and operating the fleet. Four main aspects including utilization patterns, O&M cost patterns, salvage value patterns and replacement policies are considered. The proposed approach is to use a single-period integer programming model instead of the multiple-period model that requires much higher computing power and data requirement. The approach is tested on a small numerical example in eight scenarios. Promising results of off-optimal percentage are obtained.
Evaluation of the Performance of Micro-Drills in Drilling a Machinable Ceramic Material
Authors: Shin Hyun Ho , Hwang In Joon , Lim Sung Jun , Kim Bum Sup
Published: August 2014

The performance of three different micro-drills in drilling a machinable ceramic material has been evaluated in terms of the critical feed speed (mm/min) at a given rotation rate (rpm). The critical speed is the feed speed from and above which the chipping on the rear side of the machinable ceramic material takes place. The determined critical speed turns out to increase with rotation rate in the tested range of 2k-8k rpm, forming the critical boundary line. The drilling performance of the micro-drills can be evaluated quantitatively by using the position of the critical boundary lines in the space of feed speed vs. rotation rate: the upper the critical boundary line, the higher the drilling performance of the micro-drill.
NET3D Calculation on the Depth of Penetration by a Long-Rod Penetrator with Varying Obliquity
Authors: Kim Jong Bong , Shin Hyun Ho
Published: August 2014

The effect of the obliquity of a long-rod penetrator on the depth of penetration (DOP) into a witness block has been investigated by NET3D code based on a 3D finite element model with SK constitutive model and polynomial equation of state. The calculation results herein are in general agreement with limited number of experimental data and are very close to the calculation results of the CTH code, both of which are available in the literature. By combining with the present results with existing data, the DOP turns out to decrease rapidly with obliquity up to 30o, decrease relatively slowly up to 70o, and show a saturation behavior thereafter up to 90o.
Simulation on the Life Expectancy of Fine Blanking Punch for Recreation Vehicle Seat Recliner Sector Tooth
Authors: Kim Jong Deok , Ko Hyun Jun , Kang Jeong Jin , Lee Sang Yong , Lee Sung Hee
Published: August 2014

The fine blanking product cost can be increased, however, while the precise fine blanking tool and high cost fine blanking press are required. Therefore it is very important to design the fine blanking tool in view of life expectancy of punch. In this paper the fatigue simulation of fine blanking tool punch for recreation vehicle seat recliner sector tooth was conducted with using the commercial FEA software ANSYS in order to evaluate the life expectancy of the fine blanking tool punch. Initially, the material properties were tested, the fine blanking tool was designed for production experiments. The modelling of tool elements and the fatigue simulation according to repeated loads was conducted. As a result of fatigue simulation, the fine blanking tool punch for seat recliner sector tooth had been fractured with 11,121 strokes. In the fine blanking production experiments, the fine blanking tool punch had to be regrinded, after it was used with 10,160 strokes. It would be found that the fatigue simulation of the fine blanking tool punch was conducted with an error of 8.6% .
Utilization of Tooth Contact Pattern in a Gear Meshing Model for Estimation of Sliding Loss in a Parallel-Axis Gear Pair
Authors: Phraeknanthoe Jetsada , Ponchai Natcha , Ratanasumawong Chanat
Published: August 2014

The utilization of tooth contact pattern in a gear meshing model for estimation of sliding loss in a spur and helical gear pair is presented in this paper. The photo of tooth contact pattern taken after the gear operation is used as the database to generate the simplified tooth contact pattern. Then the simplified contact pattern is used along with the gear meshing model to estimate the sliding loss of a gear pair. Experiments are done to verify the results. The estimated results from the presented method agree well with the experimental results. The presented method is able to estimate the effect of the helix angle on the sliding loss correctly whereas the estimation without using the data of tooth contact pattern cannot.
Computer Aided Design of the Die-Set for Sheet Metal Punching and Blanking Dies
Authors: Abdel-Magied R.K. , Hussein H.M.A. , Abu Qudeiri J. , Umer U.
Published: August 2014

Die-Set is one of the Punching/Blanking die components. It includes lower and upper shoes, guide posts and guide bushes. The High demand of Die-Set in industry resulted in the supply of specified die set from many manufacturing companies. The standard components in the market cover only the small and medium die sizes. In many cases, the designers need to build their own die-sets especially in case of progressive die design and non-tradition die sizes. In this paper, a CAD system for building a Die-Set is discussed. This system is built using Visual Basic (VB) interfacing with AutoCAD. The system covers all Die-Sets sizes (small, medium). The proposed CAD system is prepared to work as a standalone or as a subroutine for a blanking die design CAD system. It saves time in Die-Set design operation from hours to minutes. This module is a part of a series of studies to automate the design of sheet metal working tools.
Dynamic Equilibrium Configurations of Multibody Systems
Authors: Kang Ju Seok
Published: August 2014

It is difficult to calculate dynamic equilibrium configuration in the mechanical systems, especially with the constraint conditions. In this paper, a method to calculate the dynamic equilibrium positions in the constrained mechanical systems is proposed. The accelerations of independent coordinates are derived in the algebraic form so that the numerical solution is easily obtained by the iteration method. The proposed method has been applied to calculate the dynamic equilibrium configuration for speed governor and the wheelset of railway vehicle.
A Hybrid Approach for Process Optimization in Taper Cutting Operation Using Wire Electrical Discharge Machining
Authors: Nayak Bijaya Bijeta , Mahapatra Siba Sankar
Published: August 2014

Angular error is a major concern for the tool engineers during the taper cutting operation in wire electrical discharge machining (WEDM) process. Due to the complexity and non-linearity involved in the process, it is difficult to obtain good functional relationship between responses and process parameters. To address this issue, the present study proposes artificial neural network (ANN) model to determine the relationship between input parameters and output response. Bayesian regularization is adopted for selection of optimum network architecture because of its ability to fix number of network parameters irrespective of network size. Levenberg-Marquardt algorithm has been used to train the ANN model and the resulting network has good generalization capability minimizing the chance of over fitting. The model is developed based on the data obtained from a laboratory scale experimental set up. A set of six important input parameters such as part thickness, taper angle, pulse duration, discharge current, wire speed and wire tension is chosen to study the tapering operation in WEDM. Finally, a recent meta-heuristic approach known as Bat algorithm is used to suggest the optimum parametric combination for minimizing the angular error during taper cutting process in WEDM.
Optimization of the EDM Parameters on Machining Ti-6Al-4V Alloy with Multiple Quality Characteristics
Authors: Xess Prity Aniva , Biswas Sandhyarani , Masanta Manoj
Published: August 2014

Conventional machining methods are unable to meet the challenges postured by the demand for economic machining of ultra-hard and high strength materials. Electro discharge machining (EDM) is a promising technique with great potential for application to machining hard materials over conventional techniques. In recent years, researchers have explored a number of ways to improve the EDM process performance by studying the different factors that affect the quality characteristics. The theoretical and experimental studies showed that process performance can be improved significantly by proper selection of EDM parameters, material parameters and operating parameters. In this study, an attempt has been made for simultaneous optimization of the process performances like, metal removal rate, surface roughness and overcut based on Grey Taguchi methodology for machining of Ti-6A-4V Titanium alloy by EDM.
Thermodynamic Analysis of Hydrogen Production from Methanol Reforming in Supercritical Water
Authors: Srisiriwat Nawadee , Wutthithanyawat Chananchai
Published: August 2014

The hydrogen production via methanol reforming in supercritical water (SCW) condition has been thermodynamically investigated by a Gibbs free energy minimization method to determine equilibrium yields and energy requirements in fuel processor over the temperature range between 673 and 1273 K and water-to-methanol (H2O:MeOH) ratio of 1 – 5 corresponding to the methanol concentration from 64 to 26 wt%, respectively. In this research, the main objective is to compare the influence of operating pressure from atmospheric (ATM) pressure to SCW condition on the product yields. At ATM pressure, a hydrogen production increases with increasing reaction temperature up to 973 K while under SCW condition, an increase of temperature constantly increases the formation of hydrogen. As the reaction temperature increases, the hydrogen production and the total heat load increase but the hydrogen to carbon monoxide (H2/CO) ratio decreases. Although the hydrogen yield is constantly higher at ATM pressure than under SCW condition, the H2/CO ratios are always greater in SCW at temperatures above approximately 700 K. The amount of hydrogen and the heat load of both the preheater and the reactor also increase significantly as the H2O:MeOH ratio increases.
Structure Design Based on Mechanism and Materials Property
Authors: Liu Heng Li , Liu Bao Shun , Li Xiao Na
Published: August 2014

For products, the structure determines function; appearance form aesthetic; and the two co-exist to achieve the perfect unity of function and aesthetics, but in fact, the structure is largely affects the product shape. In this paper, classified the product structure according to function, analyzed the impact of the typical structural design to the shape of product, and also pointed out that the development of science and technology and material choice are also an important factor in the structure design, thereby affected the design of the product styling. By analyzing, it elaborated fully the impact of structural design and its importance in the product design, and provided one practical way of thinking.
Design Optimization of Hub for 3-Bladed Horizontal Axis Tidal Turbine
Authors: Kamran Muhammad , Li Zhen Yu , Zhu Shi Fan , Kong Fan Kai
Published: August 2014

In this paper, Wind turbines knowledge, which is already matured enough, is effectively used for design of horizontal axis tidal turbine (HATT) hub. Design optimization keeping in view the shape and strength for minimum weight was done using ANSYS software. Maximum stress concentration areas are found to be the blade roots and edges of shaft connection. A novel approach is used to optimize the fillet radii along with overall thickness.
A New Method of LCMV Algorithm in GNSS Anti-Interference
Authors: Zhang Xiu Qing , Diao Yan Hua , Tian Zheng Yang
Published: August 2014

Owing to the satellite signal strengths of GNSS is so low that it is interfered with powerful signal, that how to effectively resist interference is becoming a problem.In this paper,first LCMV algorithm based on the power-inversion adaptive array is deduced from theory in certain mathematical model ,what’s more ,for avoiding computing the inverse of matrix, LCMV algorithm is improved and then is verified through the Matlab-simulation .Last,the hardware design is given for the realization of this algorithm.
Analysis of Geometric Characteristic of Missile Vertical Launching System Guide Rail
Authors: Yang Ji Chao , Yang Yun
Published: August 2014

By analyzing the shipboard missile vertical launching system (VLS), we simplified the assembly model and reconstructed it with mathematical methods, established the clearance parameter and deviation angle mathematical formulas. In considering of the assembly errors of guide rail in missile vertical launcher system, we studied assembly clearance parameters effects on the system at first. And then established dynamic simulation model, researched the relationship between assembly clearance parameters and missile launching status. At last, used the above relationship model and conclusions, developed a prototype simulation method, and provided the foundation and guidance for design of missile vertical launching system.
Optimization of Multiple Performances for EDM in Gas Media Using Grey Relational Analysis
Authors: Chuang Fang Pin , Lin Yan Cherng , Chow Han Ming , Wang A Cheng
Published: August 2014

The aim of this investigation is to optimize the multiple performance characteristics of electrical discharge machining (EDM) for SKD 61 tool steel in gas media using grey relational analysis. The three most important machining characteristics namely material removal rate (MRR), electrode wear rate (EWR), and surface roughness (SR) were considered as the measures of the performance characteristics. A series of experiments were conducted according to an L18 orthogonal array based on the Taguchi experimental design method. The observed data obtained from the experiments were evaluated to determine the optimization of machining parameters correlated with multiple performance characteristics through grey relational analysis. Moreover, analysis of variance (ANOVA) was conducted to explore the significant machining parameters crucially affecting the multiple performance characteristics. In addition, the optimal combination levels of machining parameters were also determined from the response graph of grey relational grades for each level of machining parameter.