bluuebunny/crossref_metadata_2025 huggingface dataset:
A Descriptive Approach for Power System Stability and Security Assessment
Authors: Tikdari A. G. , Bevrani H. , Ledwich G.
Published: October 2013

Power system dynamic analysis and security assessment are becoming more significant today due to increases in size and complexity from restructuring, emerging new uncertainties, integration of renewable energy sources, distributed generation, and micro grids. Precise modeling of all contributed elements/devices, understanding interactions in detail, and observing hidden dynamics using existing analysis tools/theorems are difficult, and even impossible. In this chapter, the power system is considered as a continuum and the propagated electromechanical waves initiated by faults and other random events are studied to provide a new scheme for stability investigation of a large dimensional system. For this purpose, the measured electrical indices (such as rotor angle and bus voltage) following a fault in different points among the network are used, and the behavior of the propagated waves through the lines, nodes, and buses is analyzed. The impact of weak transmission links on a progressive electromechanical wave using energy function concept is addressed. It is also emphasized that determining severity of a disturbance/contingency accurately, without considering the related electromechanical waves, hidden dynamics, and their properties is not secure enough. Considering these phenomena takes heavy and time consuming calculation, which is not suitable for online stability assessment problems. However, using a continuum model for a power system reduces the burden of complex calculations. Finally, a new power system emergency control framework based on descriptive study of electrical measurements and electromechanical wave propagation in large electric power systems is introduced. Since, fast and accurate detection of instability is essential in initiating certain emergency control measures, the proposed methodology could be also useful to detect the contingency condition and performing the well-known islanding and load shedding techniques. The chapter is supplemented by some illustrative nonlinear simulations on large scale test systems.
Risk Assessment and Real Time Vulnerability Identification in IT Environments
Authors: Peotta de Melo Laerte , Gondim Paulo Roberto Lira
Published: October 2013

Contrary to static models of risk analysis, the authors propose a pro-active framework for identifying vulnerabilities and assessing risk in real-time. Instead of searching for vulnerabilities from an external point of view, where the information is obtained by simply exploring a digital asset (computational system composed of hardware and software), the authors propose that software agents (sensors) capable of providing application, configuration and location information be incorporated into assets. Any observed changes, such as physical location, software update or installation, hardware modifications, changes in security policy and others, will be immediately reported by the agent, in a pro-active manner, to a central repository. It is possible to assess risk in a certain environment comparing databases of rules and known vulnerabilities with information about each asset, collected by the sensors and stored in the central repository.
Security Risks/Vulnerability in a RFID System and Possible Defenses
Authors: Chowdhury Morshed U. , Ray Biplob R.
Published: October 2013

Remote technologies are changing our way of life. The radio frequency identification (RFID) system is a new technology which uses the open air to transmit information. This information transmission needs to be protected to provide user safety and privacy. Business will look for a system that has fraud resilience to prevent the misuse of information to take dishonest advantage. The business and the user need to be assured that the transmitted information has no content which is capable of undertaking malicious activities. Public awareness of RFID security will help users and organizations to understand the need for security protection. Publishing a security guideline from the regulating body and monitoring implementation of that guideline in RFID systems will ensure that businesses and users are protected. This chapter explains the importance of security in a RFID system and will outline the protective measures. It also points out the research direction of RFID systems.
Application of Cyber Security in Emerging C4ISR Systems
Authors: Malik Ashfaq Ahmad , Mahboob Athar , Khan Adil , Zubairi Junaid
Published: October 2013

C4ISR stands for Command, Control, Communications, Computers, Intelligence, Surveillance & Reconnaissance. C4ISR systems are primarily used by organizations in the defense sector. However, they are also increasingly being used by civil sector organizations such as railways, airports, oil, and gas exploration departments. The C4ISR system is a system of systems and it can also be termed as network of networks and works on similar principles as the Internet. Hence it is vulnerable to similar attacks called cyber attacks and warrants appropriate security measures to save it from these attacks or to recover if the attack succeeds. All of the measures put in place to achieve this are called cyber security of C4ISR systems. This chapter gives an overview of C4ISR systems focusing on the perspective of cyber security warranting information assurance.
The Servo Control System of Fabrication System for Optical Fiber Gratings Written Online
Authors: Wu Fei , Li Rui Tao , Pang Bo , Li Cong Jun
Published: October 2013

Nowadays, as a new type of optical fiber devices, with flexible structure characteristic and steady frequency-selecting performance among the key support device areas of optic fiber technology, Fiber Bragg Grating (FBG) is rapidly developed as an very important basic device.Therefore, the study of phase mask plate which will be good for the mass production of the optical fiber gratings is becoming a central issue. The appearance of phase mask plate technology makes the industrialized production of fiber optical gratings with a stable wavelength possible. This paper based on the optical fiber gratings written online is mainly about the study of related servo control system. By the design of the servo control system of phase mask plate, we will get the ideal purposes that phase mask plate is precisely positioned, torque of plate is increased and the time of picking any plate is undifferentiated.
Kinematic Optimization of a New High-Speed Press Using a GA-DE Algorithm
Authors: Sun Xi Yang , Wang Shuan Hu
Published: October 2013

The objective of this paper is to implement the optimal design of a high-speed press with a new transmission mechanism for punching. Firstly, the novel mechanism is shown and its merits are discussed. Then kinematic analysis is carried out by using the vector loop method. Additionally, the kinematic dimensions of the mechanism are derived by using a GA-DE algorithm. Finally, a comparative study for kinematics is made between original and optimized dimensions. The results indicate that proposed novel mechanism with optimized kinematic dimensions is of better output motion for high-speed punching.
The Tension Calculation of Self-Propelled, Cable-Controlled Vehicles' Cables
Authors: Li Lin , Zhang Yan Hui , Yang Ping
Published: October 2013

A self-propelled, cable-controlled vehicle is a self-propelled types ROV with a cable, its movement patterns underwater is significantly influenced by the tension of the cable. The paper analyses different force models of cable elements, provides a basis for correct usage of differential equation system in cable tension calculation, and puts forward a quick and accurate way to calculate the cable tension of self-propelled, cable-controlled vehicles.
Dynamic Characteristics of a Four-Bar Linkage-Type Continuously Variable Valve Actuation Mechanism Based on ADAMS
Authors: Qu Xiao Zhen , Liu Hao , He Hui
Published: October 2013

This paper proposes a simple mechanical CVVA mechanism using a four-bar linkage, a rotating 1st cam and two oscillating 2nd cams in addition to the conventional overhead camshaft valve train system. The fundamental operating principle of the CVVA mechanism is described. A multi-body dynamic model of the CVVA mechanism of single cylinder in ADAMS is developed according to the kinematic design and topological structure of the mechanism. Valve motions and compressive loads of the mechanism are analyzed through the various lift phases and camshaft rotating speeds. The results of the dynamic simulation demonstrate that the CVVA mechanism sustains proper performance in the valve timing and event control through the whole speed range.
Design and Research of Intelligent Fire-Fighting Robot
Authors: Cai Li , Zhang Rong
Published: October 2013

With the development of microelectronics technology and microprocessor, some intelligent robots have emerged. This paper presents a simple design of the robot based on 51-series microcomputer and multiple sensors with the optimization algorithm.The fire-fighting robot which can avoid the obstacles with the photoelectric sensors, can extinguish fire through flame detection with far infrared sensors. The particle swarm optimization algorithm is introduced into software design to improve the sensitivity of fire-fighting robot,which has the advantages of simple structure and easy control.
Simulation of PFC Algorithm in the System of Tension Control of Shaftless Driven
Authors: Huang Meng Tao , Zhou Yan Jun , Ma Jing
Published: October 2013

Through the in-depth study of working principle and application of PFC algorithm, the paper introduces PFC algorithm to the constant tension control of the system of shaftless driven in printer. In order to better implement constant tension control of shaftless driven control system, the paper choose a first order system as the transfer function of the system of tension model. The paper carries on the silulation of the system’s output of constant tension ,aiming at the situation of the changing of the internal parameters of prediction model for PFC algorithm, such as the attenuation coefficient of reference trajectory , the change of fitting points , prediction horizon and so on, matching of prediction model and tension model of PFC algorithm. The simulation system provides a theoretical basis to build the actual tension control system.
Laser Tracking System Design Performance Test
Authors: Wang Chun Yan , Wang Yi Bo
Published: October 2013

To simulate the real field environment far field, to obtain the best performance of the laser measurements of the turntable tracking system to be developed, can be locked by means of the tracking of the target, the turntable adjusting the rotational angular velocity tracking system size and rotation means, so as to simulate different motion state space moving target effect on the laser irradiation to test the performance targets to achieve the targeting system performance evaluation.
A High-Precision Binocular Measurement System
Authors: Fu Yue Gang , Jin Fan Hao
Published: October 2013

The system uses three-dimensional measurement of binocular vision theory, through optical, mechanical, computer and other aspects of the technology to measure the target without contact, and up to a certain precision. In the high-voltage area, high-altitude target,and the target which is not easy to touch, there is a unique measure advantage. Binocular stereo vision is based on the principle of parallax and using imaging devices from different locations to obtain two images of the measured object and obtain three dimensional geometric of target by positional deviation between corresponding points in computer image. Binocular stereo currently used in four areas: robot navigation, micro operating system parameter detection, three-dimensional measurements and virtual reality. In addition, the system not only to measure the length of the distant object, the system can also be used to measure the width, surface area, height and tilt angle. As the tip of an optical imaging technology this system has a broad application prospects in the future.
Applied Research on Segmented-Hilbert-Huang Transform Algorithm in Fault Feature Extraction of Main Reducer
Authors: Huang Feng Yun , Sun Huan Huan , Pan Hao , Zhang Wei Ru
Published: October 2013

For the multi-time scale characteristics of vibration signal, a composite multi-frequency dictionary combining the low-frequency Fourier dictionary and the high-frequency impulse time-frequency dictionary is constituted, to decompose multi-component vibration signal into the combination of several one-component signals. The use of empirical model decomposition (EDM) in high-frequency impulse Component signal including feature information is to realize segmented Hilbert-Huang transform of signal and to acquire the time-frequency representation of every one-component signal, which is the process of fault information extraction of vibration signal. The application of the method in main reducer fault diagnosis verifies the engineering practicability and validity of the new algorithm.
Modeling and Realization of CBTC Interlocking System Using SCADE
Authors: Wang Xi , Liu Shuo
Published: October 2013

With the rapidly growing of passenger flow in big city, Communications Based Train Control (CBTC) system is believed to be the chief choice for urban railway transportation system. Interlocking system is a key safety critical application for CBTC, as it provides trains safety routes both in normal condition and under degraded mode. To deal with the logic complexity and high demand for safety, this paper addresses a novel scheme for modeling and realization of CBTC interlocking system. Using SCADE toolset, core function model prototypes are elaborated and software codes are generated automatically. The practical application indicates that this method provides an accurate and complete description for the whole system, and offers a path to gain high quality system implementation.
Numerical Simulation on Detecting Defects in Pipes Using T(0,1) Mode Guided Wave
Authors: Zhu Long Xiang , Wang Yue Min , Sun Feng Rui
Published: October 2013

The guided-wave technology is very efficient in inspecting a large portion of pipe. In order to study the propagation property of guided wave in pipe and the interaction between guided waves and defects, pipe model was established using 3D solid finite element in the software ANSYS. Tangential displacements were prescribed on the nodes in the pipe end and the propagating of T(0,1) mode guided wave in pipes was simulated. The detecting signals for the pipe model with different defects were extracted, which matched very well with experimental result.
Temperature Measurement with CTMU
Authors: Zuo Xiao Qiong , Chen Meng Jun
Published: October 2013

The paper introduces a new low-cost temperature measurement solution. CTMU module is available in many Microchip microcontrollers.The method is to use the CTMU of microcontroller and a diode to replace the higher cost thermostat or temperature sensor.
Part Parametric Modeling Technology Research Based on Function Module
Authors: Zhang Yan Gang , Su Tie Xiong , Li Wei Huan , Mao Hu Ping , Guo Zhi Ming
Published: October 2013

Firstly this thesis summarized the research status about traditional modeling technology and the feature-based parameterized modeling technology about components. Secondly the article developed an idea of part parametric modeling technology research based on function module and its program realization method, on the basis of analyzing mechanical characteristic decomposition and building, parameter constraint condition, methods of module creating division and combination and numerical simulation of the part components modeling. In the text of the dissertation we also gave an example of gears and verified the validity and practical applicability about the text of the proposed method. Application of modular modeling technology can shorten modeling time and improve parts design efficiency for the same type and series of part. Especially it has great reference value on the creation of complex model.
The System Design and Simulation Research of Low Voltage Lockout over Current Protection about Transmission Line
Authors: Jia Jian Ping
Published: October 2013

Electricity has become the foundation of the national economy. Electric power security concerns the vital interests of people , economic development and social stability. Power system relay protection and automatic device is a reliable guarantee for safe and stable operation of power system .On the basis of the over current protection , low voltage lockout over current protection can improve the reliability of protection action by using low voltage lockout condition. The article describes the structure of low voltage lockout over current protection system and working state of it.The simulation results indicate that the system can correctly reflect the working state of protection, and it is conducive to understand the working principle of low voltage lockout over current protection . So, the system has practical application value.
A Study on the Evaluation of Wind Power Amount Using Air Flow Analysis Results by High-Rise Apartment Building Disposition in the City Center
Authors: You Ki Pyo , Kim Young Moon , You Jang Youl
Published: October 2013

High-rise buildings in the city center construction has been with diversify disposition. As there is high wind on top of high-rise buildings, wind turbines are often installs on top of high-rise buildings. However, we can expect efficient power generation only by installing when the turbine in the place of heavy wind. In this article, it tries to evaluate wind power generation by performing airflow analysis around the roof according to the disposition of high-rise buildings.
Envelope Signal of Partial Discharge Pattern Recognition Based on Wavelet Packet Transform
Authors: Luo Dong Song , Chen Kun Peng
Published: October 2013

In order to achieve the GIS fault detection and defect type recognition, four typical defect models were designed and discharge tests are carried out aiming at insulation defect as well as discharge characteristics in the GIS .With a large number of ultra high frequency envelope signal ,a method of domain feature extraction was proposed based on wavelet packet transform with singular value decomposition .The envelope signal was decomposed through wavelet packet transform first in the method, then the coefficient matrix of wavelet packet transform was built in the scale ,after that feature vectors of matrix were extracted by means of singular value decomposition. On this basis, BP neural network was took advantage of for pattern recognition .The results show that the good recognition effect was obtained with that method . Keyword: Ultra high frequency; Envelope signal; Wavelet packet transform; Singular value decomposition; BP neural network
Application of Pro/Engineer in Mobile Front Cover Product Development and Mould Design
Authors: Li Tian Xia , Chen Feng
Published: October 2013

In the mobile industry, mobile cover is the primary manifestations of the look of the phone, which is made up of complex curved surface, the cover design and directly affect the quality of phone design efficiency and competitiveness. Take mobile front cover as the example, introduced the process of product modeling and mold design using the Pro/E software. Elaborated this product 3D design method in detail, introduced with emphasis the mold design cycle and design of the parting surface, the mold die space and the core. Software applications shorten product cycles, mold design and processing cycles, improving the accuracy of product design, and reduce product development and tooling costs, proof of use efficiency characteristics of Pro/E plastic mould design.
Keywords-c Pro/E; 3D Model ; Mobile Front Cover ; Mould Design
Analysis and Design of Production Management System of Automobile Industry Based on Web
Authors: Luo Xuan
Published: October 2013

Production management is the core of the information management of automobile manufacturing industry, can help the enterprise organization and management of production. This paper analyses the important role of production management and the process in the current information management system of automobile. Put forward the design idea and overall framework based on Browser/Server 3 layer architecture model of production management system of automobile industry, designed the function module of the system according to the enterprise production and management mode and the analysis of the various functional modules, and finally the whole work flow of production management systems in the automobile industry are given. The system can effectively organize and manage the production, enhance enterprise supply capacity.
Sequential Multiple Signature Scheme Based on Wavelet Domain Digital Watermarking
Authors: Li Hui , Dong Xu
Published: October 2013

With wavelet transform multiresolution characteristics, using wavelet domain digital watermarking algorithm, we embed signed information in in the intermediate frequency subband picture which is processed by three level wavelet decomposition. Signed information not only have a good invisibility and robustness, but also enhance security. The practice shows that the scheme can effectively hide signature information in the seal picture, if attacked, the receiver can discriminate from seal image, and has better safety.
Process of Baluster for Stone Spiral Staircase
Authors: Chen Yan
Published: October 2013

In modern cities, with the rapid development of economy, various stone spiral staircases were decorated by more and more hotels or guest houses. It was very popular and showed beautiful decoration design style of modern hotel. In this paper, we studied the design process of baluster from stone spiral staircase. A new technical process for baluster of spiral staircase was investigated. We found much flaws of spiral surface in process of stone staircase and calculated a series of formulas by digital control of bead or wire saw. And one-time-molding techniques will be used in pieces processing. By sample analysis, this new method is more convenient than before. We believe that this stone spiral staircase will be used by more construction in the future.
Multifunctional Special Vehicle Design for the Viaduct Maintenance Based on Solidworks
Authors: Zhang Rong , Cai Li , Zhang Xiao Hong , Peng Xiao Ling
Published: October 2013

With the development of highway transportation, there being a rapid increasing in the number of highway bridges. On one hand, it creates a good condition for the development of our economy, on the other hand, due to the security risks often bring up a lot of tragic accidents, the issue about regular maintenance of the bridge becomes more and more important.
Having taken all above mentioned into consideration, this paper designed a special vehicle named "Viaduct Maintenance Multifunction Vehicle ". The vehicle mainly adopted the plane bear and gear combination as chassis rotary mechanism; used rack and gear meshing as elevating mechanism,and realized the trusss fliping by pneumatic circuit .As well as ,this paper included SCM system and wireless remote control technology, through them multifunctional special vehicle could provide protection for workers accomplishing altitude operations in the process of the viaduct repair and maintenance. Finally,we used three-dimensional software Solidworks for motion simulation to verify its functionality.
The Analysis on the Application of CAD/CAPP/CAM in Die Designing and Manufacturing
Authors: Zhang Hong , Chen Yang Yang , Chen Zhuo , Tang Ping
Published: October 2013

Die design and manufacturing are organic unity, primarily owning to its own characteristics. On account of the fact that curves and surfaces constitute the main inner part of die, CAD software can be applied in die designing, plotting and three-dimensional modeling. Additionally, CAPP software could be applied in the scheming of die processing while CAM software in the imitation of die manufacturing. As the intensive research and development of CAD/CAPP/CAM, computers not only offer spacious room for die design, modeling and application but also bring about great prospects for research and development of computer software.
Preparation and Characterization of Nano Particle Reinforced Polyactides Composite
Authors: Chee Ching Yern , Rosiyah Y. Yahya , Li Garlie
Published: October 2013

Polylactides (PLA) based composite films modified with nanoclay content ranges from 0-30 wt% were fabricated using solvent casting method and the mechanical properties, water vapor permeability, oxygen barrier, thermal stability and optical properties were studied. The study showed that the addition of up to 15 wt% of clay has caused a significant improvement of tensile strength of the PLA/nanoclay composite film. However, the further increasing of nanoclay content of >15 wt% of nanoclay has caused a significant reduction in tensile, elongation at break and optical properties of PLA matrix. Both the oxygen and water permeability of the PLA/nanoclay composite film decrease with the increasing of nanoclay contents. Greater water barrier properties would be achieved if the high nanoclay contents of 10-30 wt% were dispersed homogenous within the PLA matrix. The addition of nanoclay greater than 10 wt% affected the appearance of the film (i.e. increasing the haze and ΔE). Thermal analysis result has proved that the melting temperature, crystallization temperature and glass transition temperature of the composite film only slightly affected by the addition of nanoclay due to the immobilization polymer chain in the composite film.
Characterization of Fabricated Feedstock Using Nano Powders and a Water-Soluble Binder in Micro Metal Injection Molding
Authors: Javad Rajabi , Muhamad Norhamidi , Sulong Abu Bakar , Hasyimah Aziz , Fayyaz Abdolali , Zakaria Hafizawati
Published: October 2013

Micro metal injection molding has become the promising method in powder metallurgy research in order to fabricate small-scale intricate parts in an influential process and competitive cost of mass production. Stainless steel 316 L powders with powder size of 150 nm and 5 μm were mixed with a binder with a water soluble component which consisted of a major fraction of water soluble Polyethylene Glycol (PEG), a minor fraction of polymethyl-methacrylate (PMMA) and some stearic acid has been used as a surfactant. This work aims to investigate the rheological properties of a feedstock which are efficiently characterised by capillary Rheometry to measure apparent viscosities at different temperatures and shear rates. Results obtained by the varying feedstock characteristics, when viscosity decreases by increasing of shear rate at certain temperature feedstock should have a pseudoplastic behaviour. Melt viscosity of the feedstock was decreased by adding nanoscale powders. The reduced (n) values at high temperature with addition of nanoparticles indicated a possible increase in the shear-thinning behavior.
An Experimental Investigation of Cutting Forces in Hard Milling of H13 Steel under Different Cooling/Lubrication Conditions
Authors: Zhang Song , Li Jian Feng , Lv Hong Gang , Chen Wei Dong
Published: October 2013

In the present research, an attempt has been made to experimentally investigate the cutting forces in hard milling of H13 steel with coated carbide tools under dry, MQL (minimum quantity lubrication) and MQCL (minimum quantity cooling lubrication) cutting conditions. Based on Taguchis method, four-factor (cutting speed, feed per tooth, radial depth of cut, and axial depth of cut) four-level orthogonal experiments were employed. It is found that the periodical fluctuation of the cutting forces caused by the variation of the undeformed chip thickness with the entry/exit of the cutting edge is an essential feature of the hard milling process. The empirical models for cutting forces are established, and ANOVA (analysis of variance) indicates that the quadratic models can well express the relationship between cutting forces and cutting parameters.
Johnson-Cook Constitutive Equation for Titanium Alloy TC11
Authors: Chen Ming , Niu Qiu Lin , An Qing Long , Tang Si Wen , Li Peng Nan
Published: October 2013

Studying the dynamic properties of a material are an important method to understand the dynamic processes and deformation mechanism of material at different working conditions, particularly at high strain rate. The constitutive equation of a material has the highest significance to represent the mechanical properties, and is the principal research basis for the numerical simulation. In this paper, an important titanium alloy TC11 was studied through the quasi-static tensile test and the split Hopkinson pressure bar (SHPB) tests. Dynamic compressive behavior of TC11 alloy was discussed. Moreover, this paper gave the constitutive model of TC11 alloy and established the Johnson-Cook (J-C) constitutive equation.
Numerical Simulation of Single Grit Cutting
Authors: Yan Lan , Jiang Feng , Hu Zhong Wei , Rong Yi Ming(Kevin)
Published: October 2013

Grinding process can be considered as micro-cutting processes with a lot of irregular abrasive grits on the surface of grinding wheel. The study of the grit-workpiece interaction through single grit cutting is an important contribution to describe the material removal processes in the grinding process. In this study, single grit cutting processes with different process parameters (depth of cut, cutting speed) were modeled by FEM software AdvantEdge. The critical depth of cut from plowing t cutting was investigated. The simulated tangential and radial cutting forces increase sharply due to the pile-up of workpiece material in the front of single grit when the depth of cut reached to some value. And the increase extent of cutting forces at low cutting speed is larger than that at high cutting speed due to the thermal softening of workpiece material. The simulated highest cutting temperature increase first, and then decrease, finally increase again with the increase of depth of cut. And the peak value of simulated highest cutting temperature occurs near the critical depth of cut. The simulated material removal rate increases with the increase of cutting speed and depth of cut.
Experimental Study on Milling of Titanium Matrix Composites
Authors: Huan Hai Xiang , Xu Jiu Hua , Su Hong Hua , Fu Yu Can , Ge Ying Fei
Published: October 2013

Titanium matrix composites (TMCs) possess many outstanding properties and have increasing and potential application in aerospace, automobile and other industries. However, TMCs are typical difficult-to-machining material due to the rapid tool wear rate and excessive machining induced defects. In this paper, tool wear, cutting forces, cutting temperature and surface roughness were investigated when milling TMCs with Polycrystalline Diamond (PCD) and carbide tools. The results showed that the values of surface roughness obtained by carbide tools were higher than that of PCD tools under the same cutting conditions. The value of cutting temperature for PCD tool was about 75% of the carbide tools, and the main cutting force value of PCD tool was about 85% of the carbide tool. Abrasive and adhesive wear were the main wear mechanisms of PCD and carbide tools. In all, PCD tools had a better cutting performance than carbide tools during finishing milling titanium matrix composites.
Numerical Simulation for Peripheral Milling of Aero-Aluminum Alloy Based on 3D FE Model
Authors: Cui Kui Hu , Ren Cheng Zu , Chen Guang
Published: October 2013

In this paper, an advanced 3D FE model was established using ABAQUS Explicit to simulate the process of milling aluminum-alloy 7075-T7451. Taking the end edge and the side edge of single flute into consideration, the model simulated the interaction between the spiral flute and wokpiece at full depth of cut. In addition, by defining automatic element deletion criterion and locally refining mesh, this model realized chip separating from workpiece without defining of cutting layer. The simulation results were compared with experimental data to verify the correctness of the simulation model.
CFD Analysis of Cryogenic Oil Mist of Milling Cutters with Different Interior Channels
Authors: Zou Lin Tao , Zhang Song , Chen Wei Dong , Zhao Guo Qiang , Zhao Bin
Published: October 2013

In the present research, a model of the cryogenic oil mist flow field of milling cutters with different interior oil channels was conducted to determine the effects of rotational speed, temperature and flow of cold air. For the milling cutters with single direct hole and double direct holes, the increase of the rotational speed has little effect on the velocity and temperature of the measuring points at different distances along the milling cutters. For the milling cutter with double direct holes the separated streamlines of double direct holes are nearer with the rise of the distance because of the viscidity of cutting fluid. When the distance exceeds 5mm, the separated streamlines combine with each other. For the milling cutter with double helical holes the streamlines of cold air present irregularly. At last, some of the simulated results were validated.
Research on the Tools’ Life in the Dynamic Heavy-Duty Cutting Process
Authors: Hu Qiang , Liu Xian Li , Yan Fu Gang , Cheng Yao Nan , Qiao Shuai , He Geng Huang , Sun Shou Hui
Published: October 2013

In this paper, the machinability of surface is introduced, and it is obtained from the analysis that the main macroscopic factors of tool premature failure are forging defects. Through research on the mechanism and rule of heavy-duty turning tool fracture failure, the conclusion is obtained that dynamic load leads to tool fracture and breakage finally. The tool working state under dynamic load is analyzed similarly by finite element software, and the simulate result verifies accuracy of the conclusion. Finally, the critical time model of tool fracture under dynamic load is established and the prevention measures of tool premature failure are formulated, which provide reference for the improvement of production efficiency and tool breakage prediction.
The Research on Cutting Performance of Two Kinds of Ti (C,N)-Based Cermet Cutters
Authors: Zhou Ming Hu , Yang Hai Dong , Zhang Hu , Zhang Jun Sheng , Xia Xi Quan , Liu Xiao Jun
Published: October 2013

A systematic cutting test was conducted turning normalized AISI1045 carbon steel with two kinds of Ti (C, N)-based cermet cutters, which were made with micron and nanometer TiC powders. And the cutting performance and abrasion mechanism was discussed in the article. The effect of tool orthogonal clearance on tool life was also researched in this paper. Results showed that: The tool life was affected seriously by tool orthogonal clearance angle, and the optimum tool orthogonal clearance angle of Ti (C, N)-based cermet cutter was 5°when cutting normalized AISI1045 steel. The cutting Performance of Ti (C, N)-based cermet cutters which were made with nanoTiC powders was better than the ones which were made with micron TiC powders obviously. And the primary wear behaviors were wear.
The Design and Finite Element Simulation Analysis of the Tool in Milling Titanium Alloys
Authors: Zhu Cai Li , Huang Shu Tao , Zhou Li
Published: October 2013

In this paper, considering material properties and processing characteristics of titanium alloys, the milling tool under the machining condition of large cutting depth and quasi-high speed is designed, and the face milling cutter with integral CBN inserts is developed. Then, the solid model of the CBN face-milling cutter is built by the three-dimensional modeling software Pro/E. At the same time, based on the platform of finite element simulation analysis, the deformation and stress analysis of the overall structures are carried out. It turns out that: the maximum stress of the cutter blades is not in the cutter tip region but distributed approximately along the direction of the main cutting edge, the maximum stress of the tool body is at the bottom of the groove for insert. The maximum stress acting on the wedge is at the bottom of the contact area between the wedge and the cutter body. Strength sensitive area of the clamping screw happens in the connection root. Through the static analysis, the reasonableness of structural design of the tool is evaluated theoretically.
Stress Analysis on the Cutting Edge Based on Design of Micro-Cutting Tool
Authors: Jiang Fang , Wang Xi Bin , Liu Zhi Bing , Wang Huai Ming
Published: October 2013

Stress analysis on wedge zone is an important step for micro-cutting tool design. The effect of stress borne by the cutting tool upon the radius of its blunt edge was analyzed, when the tool machines with minimum cutting thickness which is confined within 10-4-10-2mm. It shows that the minimal extreme value of the radius of blunt edge is existed in the process of micro-cutting tool design.
Research on Cutter Location Optimization of Tapered Ball End Mill Finish Flank Milling Ruled Surface Blade
Authors: An Shuo , Cheng Yao Nan , Liu Xian Li , Li Mao Yue , Shi Lei
Published: October 2013

For the low efficiency and poor surface quality problem of finishing ruled surface blade in the traditional method, tapered ball end mill cutter location optimization methods had been proposed to ensure that the envelope surface of tapered ball end mill is close to intractable ruled surface blade as much as possible. First, the tapered ball end mill initial cutter location was obtained based on the improved two point offset algorithm. Then to realize the cutter location optimization calculation, selected three point in tool axis to slide for the target of the minimum range between cutter envelope surface and blade surface. Finally, the blades instance was calculated according to the obtained tool center point and optimized tool axis vector. Simulation and experiments verified the effectiveness of cutter location optimization method proposed in this paper.
A Scientific Method of Tool Life Evaluation for Large Cylinder Section Cutting Database
Authors: Liu Ming , Zheng Wen Juan , Liu Xian Li , Zhang Bo , Zhang Hui Ping
Published: October 2013

Cutting database; Image processing; Large cylinder section; Tool life evaluationAbstract. This paper builds the optimization database system of cutting parameters for large cylinder section. The system is based on Browser/Server mode (B/S). The system can optimize cutting parameters, store knowledge, query information, maintain system, assess tool life and design tool. It completes the optimization of cutting parameters, according to the cutting parameters to design and evaluate the properties of cutting tools. It introduces tool life evaluation, data analysis and storage model. This paper also points out the method of tool life evaluation to achieve the collection of data of the tool cutting performance and the accurate and scientific evaluation of tool life.
Experiment Research Progresses of Single Abrasive Grain Grinding
Authors: Deng Zhao Hui , Liu Wei , Wan Lin Lin , Tang Hao
Published: October 2013

Grinding Mechanism is very complex and difficult, and it can be simplified to a single abrasive grain grinding research. With the analysis of process and result of single abrasive grain grinding from experiment, the purpose can be achieved of understanding the complexity of the grinding mechanism. According to the characteristics of grinding process, the current domestic and international research status of single abrasive grain grinding experiments is introduced. The different experimental methods used by scholars are analyzed in detail, as well as grinding characteristics of single abrasive grain and chip formation mechanism of different characteristics materials. Finally, the current research difficulties of theory and experiment research are analyzed for the single abrasive grain grinding, and the further research direction is made.
Experimental Research on Double-Side Lapping of Cylindrical Roller by Taguchi Methods
Authors: Feng Ming , Yao Wei Feng , Zhou Wen Hua , Lv Bing Hai , Deng Qian Fa , Yuan Ju Long
Published: October 2013

The rolling element is the most important component of rolling bearings. Its geometric accuracy and consistency affect greatly the performance and working life of bearings. In this paper, a standard Taguchi L9(34) orthogonal array(oa) is designed to analyse how abrasive size, rotating speed of plates, deflection angle of carrier holes and other factors impacting on precision of cylindrical roller process and achieved the optimized parameters combination by adopting evaluation of Signal-to-Noise ratio and ANOVA analysis(analysis of variance). Under the optimized lapping condition, the roundness,pand s can reach , and respectively.
Research on Thermal Resistance of Micro Heat Pipe with Sintered Wick
Authors: Li Xi Bing , Wang Xun , Ma Yun Shi , Cao Zhong Liang
Published: October 2013

As a highly efficient heat dissipation unit, a micro heat pipe is widely used in high heat flux microelectronic chips, and its thermal resistance is crucial to heat transfer capacity. Through analyses of the structure and heat transfer performance of a circular heat pipe with sintered wick, the theoretical model of total thermal resistance was established on heat transfer theory, and then simplified, finally a testing platform was set up to test for total thermal resistance performance. The testing results show that when the micro heat pipe is in optimal heat transfer state, its total thermal resistance conform well with that from the theoretical model, and its actual thermal resistance is much lower than that of the rod made of the material with perfect thermal conductivity and of the same geometric size. With the increment of heat transfer capability, the total thermal resistance of a micro heat pipe with sintered wick decreases first, then increases and reaches the minimum when it is in the optimal heat transfer state. The greater total thermal resistance in low heat transfer performance is mainly caused by too much working fluid accumulating in evaporator and the lower velocity in vapor cavity, and the greater total thermal resistance in high heat transfer performance is mainly due to the working fluid drying up in condenser. Total thermal resistance is related to many factors, such as thermal conductivity of tube-shell material, wall thickness, wick thickness, copper powders grain size and porosity, the lengths of condenser and evaporator, and the diameter of vapor cavity etc.. Therefore, the structure parameters of a micro heat pipe with sintered wick should be reasonably designed according to the specific conditions to ensure its heat transfer capacity and total thermal resistance to meet the requirements.
Cutting Forces and Surface Roughness in High-Speed End Milling of Ti6Al4V
Authors: Wang Fu Zeng , Zhao Jun , Li An Hai , Zhao Jia Bang
Published: October 2013

In this paper, high speed milling experiments on Ti6Al4V were conducted with coated carbide inserts under a wide range of cutting conditions. The effects of cutting speed, feed rate and radial depth of cut on the cutting forces, chip morphologies as well as surface roughness were investigated. The results indicated that the cutting speed 200m/min could be considered as a critical value at which both relatively low cutting forces and good surface quality can be obtained at the same time. When the cutting speed exceeds 200m/min, the cutting forces increase rapidly and the surface quality degrades. There exist obvious correlations between cutting forces and surface roughness.
Turning of Cast Inconel 718 with Coated Carbide and Whisker Reinforced Ceramic Tools
Authors: He Lin Jiang , Xu Jiu Hua , Su Hong Hua , Chen Yan
Published: October 2013

Nickel-based alloy is known as one of the most difficult-to-machine materials. During the machining process, the high temperature coupled with high strength and work hardening leads to excessive tool wear, short tool life, low productivity, etc. Tool life and material removal rate are the two targets of rough machining. In this paper, some turning tests are conducted to investigate the tool lives and material removal rate of coated carbide tools and whisker reinforced ceramic tools. The results show that notch wear is the dominant failure mode for whisker reinforced ceramic tools while severe flank wear and micro-chipping for coated carbide tools. The whisker reinforced ceramic tools are more effective in machining nickel-based alloys than the coated carbide tools both in tool life and material removal rate.
Analysis of Wind Load Effect on Ship Loader in Shipping Process
Authors: Zhou Meng Long , Lin Bin , Zhang Xu , Zhang Xiao Feng , Liu Peng Fei
Published: October 2013

Research about sea wind load effect on ship loader is completed in this paper. Entity modeling method and solid element is used in the process of finite element modeling. Sea wind is divided into the steady wind and the turbulent wind. The steady wind is disposed as the constant speed wind which can be converted to wind pressure. After the static load solution, modal analysis is conducted which is essential for the following dynamic analysis. Because turbulent wind has random amplitude, direction and frequency, random vibration analysis method is used in the dynamic analysis process. With the results from the three representative positions, it is concluded that the displacement size and dynamic response intensity is in direct proportion to the height of the position.
Energy Characteristics Analysis of Engineering Ceramics during the Process of Edge Chipping Based on AE
Authors: Tang Xiu Jian , Zhang Bao Guo , Tian Xin Li , Zhou Ze Yun , Ge Hui
Published: October 2013

To study the failure process of edge chipping for engineering ceramics, a method of energy analysis is used. Acoustic emission parameters such as energy, cumulative energy and amplitude collected in the experiment system are analyzed in this paper. The results show that energy and cumulative energy change little, amplitude changes among 40dB to 60dB before fracturing; the main reason for these is the micro-cracks propagation. While edge chipping engenders, energy, cumulative energy and amplitude would increase sharply and reach to the maximums; the main reason for these is the macro-cracks coming into being, and lots of energy release out. The change regulars of different parameters have reflected types of acoustic emission source. The method of energy could reveal the fracture mechanism of edge chipping for engineering ceramics well.
Ringing Effect and Reversed Current Analysis of RC-Pulse Generator in Electrical Discharge Machining
Authors: Zhang Min , Zhang Qin He , Kong De Zheng , Bai Xue
Published: October 2013

RC-pulse generator has a simple structure and it is easy to be made and repaired. Especially RC-pulse generator can provide high frequency and low energy discharges. Therefore RC-pulse generators are used in micro-EDM field. But its high tool wear ratio and low efficiency restrict its applications. Ringing effect is considered to have effect on the defects. This research was done to study the ringing effect in electrical discharge. Taguchi method was used and discharge curves of voltage and current were recorded and analyzed. Ringing effect plays a key role in discharges and reversed current. A waveform model established with ringing effect theory is almost the same as the waveforms recorded in the experiment. Reversed current exists in almost a half time of discharge period which is the representation of ringing effect. Suitable process parameters can reduce reversed current and proper improvements could eliminate reversed current which will reduce the tool wear ratio and increase the efficiency in RC-pulse generator.