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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean Society for Precision Engineering
Journal Basic Information
Journal DOI :
Korean Society of Precision Engineering
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Volume & Issues
Volume 20, Issue 12 - Dec 2003
Volume 20, Issue 11 - Nov 2003
Volume 20, Issue 10 - Oct 2003
Volume 20, Issue 9 - Sep 2003
Volume 20, Issue 8 - Aug 2003
Volume 20, Issue 7 - Jul 2003
Volume 20, Issue 6 - Jun 2003
Volume 20, Issue 5 - May 2003
Volume 20, Issue 4 - Apr 2003
Volume 20, Issue 3 - Mar 2003
Volume 20, Issue 2 - Feb 2003
Volume 20, Issue 1 - Jan 2003
Selecting the target year
Fuzzy Logic Controlled Seat Cushion Orthosis to Prevent Decubitus Ulcer
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 7~25
Restoration of Motor Function using Electrical Stimulation : Functional Electrical Stimulation (FES)
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 26~35
Gait Improvement of polio Patients Using an Electromechanical KAFO
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 36~42
Micro Electrochemical Machining Characteristics and Shape Memory Effect in Ni-Ti SMA
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 43~49
In this study, micro electrochemical machining method was introduced for accomplishment the fabrication technology of functional parts and smart structures using the Ni-Ti shape memory alloy. From the experimental result, the micro part which has very fine surface could be achieved by use of micro electrochemical process with point electrode method. Concretely, the optimal performance of micro electrochemical process in Ni-Ti SMA was obtained at the condition of approximately 100% of current efficiency and high frequency pulse current. That is, much finer surface integrity and shape memory effect can be obtained at the same condition mentioned above.
Critical Review on Carcinogenicity of Metalworking Fluids
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 50~62
Exposure to metalworking fluids (MWFs) has significantly been associated with cancer developed in multi-organs, respiratory diseases and skin diseases. Several carcinogens to humans or animals are contained in MWFs. They have been reported to be mineral oils, polynuclear aromatic hydrocarbons (PAHs), formaldehyde and N-nitrosodiethanolamine (NDELA). The great hazards of MWF have forced the advanced country including United States to regulate carcinogens contained in MWF. In 2001, American Conference of Governmental Industrial Hygienists (ACGIHs) regarded MWF mist as suspected carcinogen to human (A2) and added it to “Notice of Intended Change (NIC)” list of 2001. In spite of the fact that much MWF has widely been used in many industries using machines, Korea has no legal actions for management of MWF. What is worse, even toxicity such as Carcinogenicity has not been reported. KS (Korean Standards) lists 7 advices of MWF but it does net state the hazards to health. It is very hard to control or minimize worker's exposure to MWF containing many carcinogens. Prier to the introduction of MWF to workplace, it is the most effective measure to regulate carcinogens below a certain level. Regulation on the content of PAH seems to be necessary because less amount of PAH in mineral oils improves the quality of MWF. Also, addition of nitrosating groups to MWF should be prohibited to minimize worker's exposure to NDELA. Employers and manufacturers should indicate the Carcinogenicity of all carcinogens in MWFs in Material Safety Data Sheets (MSDS) in order fer workers to recognize Carcinogenicity. Legal actions have to be taken to protect workers from health hazards due to exposure to MWF by further investigation on MWF.
Construction of Attractor Simulator for Cutting Characteristics Evaluation of Non-Ferrous Metals
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 63~69
This study proposes the construction of attractor simulator for cutting characteristics evaluation of non-ferrous metals. Also this paper aims to find the optimal cutting conditions of diamond turning machine by measuring surface form and roughness to perform the cutting experiment of non-ferrous metals, which are aluminum, with diamond tool. As well, according to change cutting conditions such as feed rate, cutting force and surface roughness are measured by tool dynamometer. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics. Constructed attractor in this study can be used for cutting characteristics evaluation of non-ferrous metals
A Study on the Hand Drum Form Predict in the Wire Electric Discharge
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 70~78
The purpose of this study was to present the method to choose the optimization machining condition for the wire electric discharge machine. This was completed by examining the ever-changing quality of the material and by improving the function of the wire electric discharge machine. Precision metal mold products and the unmanned wire electric discharge machining system were used and then applied in industrial fields. This experiment uses the wire electric discharge machine with brass wire electrode of 0.25mm. In this experiment, we changed no-node voltage to 7 and 9, pulse-on-time to 6
, pulse-off-time to 8
, and experimented on wire tension at room temperature by 1000gf, 1200gf, and 1400gf, respectively.
Laser Marking Process for LCD Light Guide Panel
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 79~84
A light guide panel is an element of the LCD backlight module that is often used for the display of compact electronic devices. In this study, a laser marking system is proposed to fabricate light guide panel, which can replace other manufacturing methods such as silk printing, stamping, or v-cutting methods. The objective of this research is to evaluate the process parameters of the laser marking system. Light guide patterns were marked with a 50W
laser (CW) to understand the effects of average power and scanning speed on the geometry and quality of groove pattern. The width of the fabricated grooves increases with increasing laser power and decreasing scan speed. In order to analyze surface characteristics and optical properties (luminance, uniformity), SEM photography and BM7 (luminance measuring system) were used. As a result, the optimal conditions of the process parameters were determined.
Effects of Change of Wafer Shape through Heating on Chemical Mechanical Polishing Process
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 85~90
Removal rate and Within Wafer Non-Uniformity (WIWNU), the most critical issues in Chemical Mechanical Polish (CMP) process, are related to the pressure distribution, wafer shape, slurry flow, mechanical property of pad and etc. Among them, wafer warp generated by other various manufacturing process of wafer may induce the deviation of pressure distribution on the backside of wafer. In the convex shaped wafer the pressure onto the backside of wafer is higher than that of perfectly flat shaped wafer. Besides, such an added pressure is in proportion to the curvature of wafer. That is, the bigger the curvature of wafer becomes the higher the removal rate goes. And the WIWNU is known to be directly related to the pressure distribution on the wafer as well. In other words, the deviation of pressure distribution is in proportion to the WIWNU. In this paper, it is found that the wafer shape may be modified through heating the backside of it and thus properly changed pressure onto the backside of it may improve the WIWNU.
A Study of Rapid Tooling of Porous Metal Mold
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 91~98
Removal of gas in a mold has been a big problem in pressing mold or in injection mold. Air vent has been used to solve the problem, but it has weak points such as the increased cost, the increased number of process, and vent marks on the surface of a product. In this study, the sintering method and rapid tooling method are used for making porous metal mold. Porous metal mold has many open pores, which are very small. When porous metal mold is used for pressing mold or injection mold, all process would be made short, produce cost would be down, and vent marks would be not leaved on the surface of a product. Characteristic of porous material varies from sintering conditions, which are the length of sintering time, sintering temperature and sintering atmosphere etc. This study will find optimized sintering condition for the porous metal mold.
Recognition of the Center Position of Electric Line Using Modified Hough Transform
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 99~106
Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. The maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system. In order to realize these tasks autonomously, the there dimensional position of target object such as electric line and the stand of insulator must be recognized accurately and rapidly. The insertion task of an electric line into a sleeve is selected as the typical task of the maintenance of active electric power distribution lines in this paper. A modified hough transform is applied to the recognition of the center of electric line and optimal target position calculation method is newly derived in order to recognize the center 3 dimensional position of the electric line. By the proposed method, it is proved that the center position of the electric line can be recognized without respect to the noise of image and the shape of electric lines and the insertion task of an electric tine is realized.
Development of Automatic Polishing Robot System and Integrated Operating Program
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 107~117
Polishing a die that has free-form surfaces is a time-consuming and tedious job, and requires a considerable amount of high-precision skill. In order to reduce the polishing time and cope with the shortage of skilled workers, an automatic polishing robot system was developed. The polishing robot system is composed of two subsystems, a three-axis machining center and a two-axis polishing head. The machining center is controlled by a FANUC controller, and the polishing head by DSP controller. The system has five degrees of freedom and is able to keep the polishing tool normal to the die surface during operation. To easily operate the developed polishing robot system, this study developed an integrated operating program in the Windows environment. The program consists of five modules: a polishing data generation module, a code separation module, a polishing module, a graphic simulator module, and a teaching module. And, the automatic teaching system was developed to easily obtain teaching data and it consists of a three dimensional joystick and a proximity sensor. Also, to evaluate the performance of the integrated operating program and the polishing robot system, polishing experiments of a die of shadow mask were carried out.
Development of Tool Item Selection System Aiding CAM Procedure for Injection Mold
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 118~125
As consumer's desire becomes various, agility of mold manufacturing is the most important factor for competitive mold manufacturer. Decision making process is required to produce optimal result of CAM systems in using commercial CAM system to generate tool path. The paper proposes a methodology fur computer-assisted tool selection procedures for various cutting type of rough, semi-rough and finish cuts. The procedure provides assistance for machining tool selection by analyzing sliced CAD model section of die cavity and core. Information about machining time for the generated NC-code is used to aid the tool selection. The module is developed with commercial CAM API. This module will be used fur the optimization of tool selection and planning process.
Environmentally-Conscious Cleaning System for End-of-Life CRT
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 126~134
In this study, we suggest a environmentally-conscious and dry cleaning process mechanism for the more useful recycling of end-of-life CRT, and also develop a prototype cleaning system to verify the faulty of the designed mechanism. This system accommodates the specifications of 14∼32" end-of-life CRT. In experimental result, it is expected that the developed system improve the productivity up to 10% and decrease the loss rate of cleaning glass 3∼4 times than the glass blasting methods.
A Study on the Automatic Design of Dies for Hot Extrusion of Aluminium Alloys
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 135~143
This study presents development of a automatic design software for process and die design of hot extrusion of aluminium alloys through square dies. The design of extrusion dies is still an art rather than a science with increasing complexity of shape and thinness of section. Therefore, most of the die design is still dependent on personal judgement, intuition and experience. The objective of this study is to develop a software system which includes a design rule extracted from literatures and experts in the extrusion industry. The developed system is effectively used to design extrusion processes and dies with reduced lead time and trial extrusion.
Effect of Composition on Cutting Characteristics of Ti(C,N) Cermet Tool
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 144~150
When WC and group IV elements are added to Ti(C,N)-Ni substrate, microstructures of the cermet is changed. The microstructure gives direct effect on the property of the material. In this study, the amount of WC and group W elements of Ti(C,N) cermet tool was investigated. The composition of WC was changed from 5 to 20wt% to determine the effect of WC on the cutting performance of cermet tool. The more WC was added, the longer the tool life of the cermet tool was. The cermet with 20wt% WC showed the best fracture toughness. The effect of group W elements; ZrC, ZrN and HfC was also investigated by adding each of them to manufacture the cermet tool with fixed l4wt% WC composition. The cermet with 1wt% ZrC and 14wt% WC showed the best cutting performance among the investigated cermet tools.
Change Impact Analysis in Engineering Design Process
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 151~158
Design changes frequently occur while design activities are performed. If the impact of design changes is estimated, design efficiency can be improved. But, the types of design changes are various and they can affect other design parts. Hence, it is difficult to deal with design changes directly. The purpose of this research is to develop systematic algorithms for change propagation tracing and change impact analysis, and then to implement a change impact analysis system. We have selected a process-based design and a design environment which is composed of design parameters and constraints. The algorithm for change propagation tracing tracks the change propagation of design parameters and finds design parameters, constraints and tasks which are probably changed. In the algorithm for change impact analysis, a change impact value is calculated from the list of changeable tasks. These two algorithms have been implemented into change impact analysis system (CIAS). CIAS has been applied to the redesign of 2 stage gear drives. CIAS can improve the efficiency of design activities. If there are many alternatives for a design change at the redesign step, designers can calculate the change impact value of each alternative and perform design change activities in the direction of minimizing design change impact.
Determination of Design Parameters for Automobile Parts Recycling
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 159~171
In this paper, same parts of a domestic automobiles and foreign automobiles are disassembled fur the evaluation of disassemblability, especially door trim and bumper. Influencing factors of disassembly are determined by the classification of bottleneck process in disassembly process. On the bases of disassembly sequence and structure of parts and subassembly, disassemblability is classified into aye categories. The influencing factors, which are related with the five categories are determined. By these relations, the checklist for disassembly evaluation is draw up and score tables of checked factors are established. For the establishing the disassembly score tables, the weighting values of each five categories are calculated by the disassembly test of automobiles and then, the weighting values of each influencing factors of five categories are calculated by the method of AHP (Analytic Hierarchy Process). And the last, the weighting values are modified and recalculated from the disassembly test. Using these weighting values, the score of influencing factors are determined and then, the score tables are established based on the score of influencing factors.
An Analysis of Dynamic Characteristics of Bolted Lap Joints with Viscoelastic Layers
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 172~178
Two types of bolted lap joints, one with a viscoelastic layer and the other without the viscoelastic layer were chosen to analyze the dynamic characteristics of the joints with the mechanical properties of the bolts in the joints are considered as computational variables. The finite element method was used along with the modal testing to verify the PEM model. The results in the bolted lap joints reveal that the higher the Young's modulus for the bolts we use the higher the natural frequencies we obtain fur the joints. However, the natural frequency differences in the first and second mode are not substantial but become noticeable in the higher modes. Lower natural frequencies were obtained for the bolted lap joints with the viscoelastic layer when compared with those of the bolted lap joints without the viscoelastic layer. And the differences in the natural frequencies for the two types of joints are relatively small in the first and second mode whereas in the higher mode the differences become significant. The loss factors were observed to be significant especially in the second mode for the bolted lap joints with the viscoelastic layer.
Wear Characteristics of Submerged-Arc Cladding
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 179~186
This paper is to investigate the wear behavior of submerged-arc claddings by the wear test with a ball-on-disk type wear testing machine in air. The specimens were clad with Stoody105 alloy wire on a medium carbon steel (SM45C) substrate by submerged-arc cladding process under different welding parameters. The wear behavior of the cladding through ball-on-disk test has been studied under the wear load from 5 to 16 N and the sliding speed from 8 to 35 cm/s. The weight loss of the specimen was measured. Scanning electron micrographs of the worn surface show a layer of oxide film formed on the worn surface. Oxidation wear mechanism controls the wear process. The spatting of the oxide is caused by the repeated rubbing fatigue mechanism.
A Study on the Vehicle Dynamic Characteristic of Displacement Sensitive Shock Absorber
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 187~195
The performance of shock absorber is directly related to the car behaviour and performance, both for handling and ride comfort. The displacement sensitive shock absorber has two modes of damping force (i.e. soft and hard) according to the position of piston. In this study, a mathematical nonlinear dynamic model is introduced to predict the performance of displacement sensitive shock absorber. Especially in this paper, the transient zone is considered and the simulation result is well fit with experimental data. And the vehicle dynamic characteristic of displacement sensitive shock absorber is presented using quarter car simulation model. The simulation results of frequency response are compared with passive shock absorber.
Dynamic Deformation Behavior of Aluminum Alloys under High Strain Rate Compressive/Tensile Loading
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 196~204
Mechanical properties of the materials used for transportations and industrial machinery under high strain rate loading conditions such as seismic loading are required to provide appropriate safety assessment to these mechanical structures. The split Hopkinson Pressure Bar (SHPB) technique with a special experimental apparatus can be used to obtain the material behavior under high strain rate loading conditions. In this paper, dynamic deformation behaviors of the aluminum alloys such as A12024-T4, A16061-T6, and A17075-T6 under both high strain rate compressive and tensile loading conditions are determined using the SHPB technique.
Development of an Automated Design System of CNG Composite Vessel using Steel Liner Manufactured by D.D.I Process
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 205~213
The fiber reinforced composite material is widely used in the multi-industrial field where the weight reduction of the infrastructure is demanded because of their high specific modulus and specific strength. It has two main merits which are to cut down energy by reducing weight and to prevent explosive damage preceding to the sudden bursting which is generated by the pressure leakage condition. Therefore, Pressure vessels using this composite material in comparison with conventional metal vessels can be applied in the field such as defense industry, aerospace industry and rocket motor case where lightweight and the high pressure are demanded. In this paper, for nonlinear finite element analysis of E-glass/epoxy filament winding composite pressure vessel receiving an internal pressure, the standard interpretation model is developed by using the ANSYS, general commercial software, which is verified as the accuracy and useful characteristic of the solution based on Auto LISP and ANSYS APDL. Both the preprocessor for doing exclusive analysis of filament winding composite pressure vessel and postprocessor that simplifies result of analysis have been developed to help the design engineers.
Evaluation of Fatigue Strength by Graphite in Ductile Cast Iron
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 214~221
In this study, based on the effect of the interaction of fracture mechanics by graphite and fatigue limit phenomena of the microscopic observation various matrix structure, spheroidal ratio, size of graphite and distribution etc. parameters containd with Ductile Cast Iron. Therefore, in this study, different ferrite-pearlite matrix structure and spheroidal ratio of graphite of 70%, 80% and 90%, GCD40, GCD45-1 and GCD45-2 series and three different ferrite-pearlite matrix structure, GCD 45-3, GCD 50, GCD 60 series, all of which contain more than 90% spheroidal ratio of graphite, were used to obtain the correlation between mean size of spheroidal graphite and fatigue strength. (1) 73% pearlite structure had the highest fatigue limitation while 36% pearlite structure had the lowest fatigue limitation among ferrite-pearlite matrix. the increase in spheroidal ratio with increasing fatigue limitation, 90% had the highest, 14.3% increasing more then 10%, distribution range of fatigue life was small in same stress level. (2) (equation omitted) of graphite can be used to predict fatigue limit of Ductile Cast Iron. The Statistical distribution of extreme values of (equation omitted) may be used as a guideline for the control of inclusion size in the steelmaking processes.
A Study on Tool Wear Diagnosis by Measuring Spindle Displacement
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 222~228
A reliable tool wear monitoring technique is the one of important aspects for achieving an integrated and self-adjusting manufacturing system. In this paper, a tool wear estimation approach for turning is proposed. This approach uses the model of cutting force, spindle displacement and their relation. A series of experiments were conducted by designing experimental techniques to determine the relationship between flank wear and cutting force coefficient as well as cutting parameters such as cutting speed, depth of cut and feed. The proposed model performance has shown that the spindle displacement model predicts tool wear with high accuracy and spindle displacement signal is possible to replace cutting force signal.
Development of Integrated Design System for Structural Design of Machine Tools
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 229~239
The design process of machine tools is regarded as a sequential, discrete, and inefficient works as it requires various kinds of design tools and many working hours. This paper describes an integrated design system embedding a design methodology that can support efficiently and systematically the conceptual structural design of machine tools. The system is a knowledge-based design system and has four machine-tool-specific functional modules including configuration design, configuration analysis, structure design, and structural analysis support module. Through the configuration design and analysis module, a machine configuration appropriate for design requirements is selected, and then the arrangement of ribs fer each structural part is decided in the structure design module. Also, the structural analysis support module is used to evaluate design result by utilizing structural analysis software, ANSYS. The system is applied to design of a tapping machine, and shows that the machine structure can be designed fast and conveniently by processing each design step interactively.
Tribological Characteristics of FDTS & OTS SAM according to Annealing Temperature
Journal of the Korean Society for Precision Engineering, volume 20, issue 1, 2003, Pages 240~247
The tribological characteristics of FDTS (1H, 1H, 2H, 2H-Perflurodecyltrichlorosilane) SAM (self-assembled monolayer) and OTS (octadecyltrichlorosilane) SAM treated by high temperature annealing have been investigated from the viewpoint of stiction, adhesion and friction in micro/nano scale. From the experimental results, it was found that OTS SAM gets destroyed at 20
and stiction, adhesion and friction coefficient increased, but FDTS SAM was stable up to 40
. Also, it was found that the friction coefficient of normal OTS SAM below 20
is lower than that of FDTS SAM in micro/nano scale, but stiction and adhesion is vice versa. This work shows the importance of surface group of self-assembled monolayer in dictating the tribological characteristics and thermal stability.