Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of The Korean Society of Manufacturing Technology Engineers
Journal Basic Information
Journal DOI :
The Korean Society of Manufacturing Technology Engineers
Editor in Chief :
Volume & Issues
Volume 23, Issue 6 - Dec 2014
Volume 23, Issue 5 - Oct 2014
Volume 23, Issue 4 - Aug 2014
Volume 23, Issue 3 - Jun 2014
Volume 23, Issue 2 - Apr 2014
Volume 23, Issue 1 - Feb 2014
Selecting the target year
A Hybrid Search Method Based on the Artificial Bee Colony Algorithm
Lee, Su-Hang ; Kim, Il-Hyun ; Kim, Yong-Ho ; Han, Seog-Young ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 213~217
DOI : 10.7735/ksmte.2014.23.3.213
A hybrid search method based on the artificial bee colony algorithm (ABCA) with harmony search (HS) is suggested for finding a global solution in the field of optimization. Three cases of the suggested algorithm were examined for improving the accuracy and convergence rate. The results showed that the case in which the harmony search was implemented with the onlooker phase in ABCA was the best among the three cases. Although the total computation time of the best case is a little bit longer than the original ABCA under the prescribed conditions, the global solution improved and the convergence rate was slightly faster than those of the ABCA. It is concluded that the suggested algorithm improves the accuracy and convergence rate, and it is expected that it can effectively be applied to optimization problems with many design variables and local solutions.
Fabrication of Micro-reactor by 3D Printing Machine
Choi, Hae Woon ; Yoon, Sung Chul ; Ma, Jae Kwon ; Bang, Dae Wook ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 218~222
DOI : 10.7735/ksmte.2014.23.3.218
A 3D printer was used to fabricate a micro-TAS system for biomedical applications. A polymeric medical device fabrication based on a 3D printer can be performed at atmospheric conditions. A CAD- and CAM-based system is a flexible method to design medical components, and a 3D printer is a suitable device to perform this task. In this research, a 100-micron-wide fluidic channel was fabricated with a high-aspect ratio. A cross-sectional SEM image confirmed its possible usage in a micro-reactor using 3D printers. CNC-machined samples were compared to 3D printer-fabricated samples, and the advantages and disadvantages were discussed. Based on the SEM images, the surface roughness of the 3D printed reactor was not affected by wet or dry conditions due to its manufacturing principle. An aspect ratio of 5 to 1 was achievable with 100-
m-wide fluid channels. No melting was found, and the shape of channels was straight enough to be used for micro reactors.
Vibration Characteristics of Cantilever Beam with a Crack
Kim, Jong-Do ; Jo, Ji-Yun ; Yoon, Moon-Chul ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 223~229
DOI : 10.7735/ksmte.2014.23.3.223
In this paper, the natural frequency and damping ratio are analyzed with the acceleration signal of an Euler-Bernoulli beam using the impact hammer test. The results are presented according to crack depth and position using the recursive least squares method. The results are compared and investigated with FEM analysis of CATIA. Both methods agree well with each other regarding the natural mode characteristics. The captured acceleration can be used for the calculation of the natural frequency and damping ratio using time series methods that are based on the measured acceleration. Using these data, a recursive time series model with the acceleration signal was configured and the behaviors of the natural frequency and damping ratio were investigated and analyzed. Finally, the results can be used for the prediction of crack position and depth under different crack conditions for an Euler-Bernoulli beam.
Wafer Level Package Design Optimization Using FEM
Ko, Hyun-Jun ; Lim, Seung-Yong ; Kim, Hee-Tea ; Kim, Jong-Hyeong ; Kim, Ok-Rae ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 230~236
DOI : 10.7735/ksmte.2014.23.3.230
Wafer level package technology is added to the surface of wafer circuit packages to create a semiconductor technology that can minimize the size of the package. However, in conventional packaging, warpage and fracture are major concerns for semiconductor manufacturing. We optimized the wafer dam design using a finite element method according to the dam height and heat distribution thermal properties. The dam design influences the uniform deposition of the image sensor and prevents the filling material from overflowing. In this study, finite element analysis was employed to determine the key factors that may affect the reliability performance of the dam package. Three-dimensional finite element models were constructed using the simulation software ANSYS to perform the dam thermo-mechanical simulation and analysis.
Prediction of Impact Life Time in Solder Balls of the Board Level Flip Chips by Drop Simulations
Jang, Chong Min ; Kim, Seong Keol ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 237~242
DOI : 10.7735/ksmte.2014.23.3.237
Recently much research are has been done into the compositions of lead-free solders. As a result, there has been a rapid increase in the number of new compositions. In the past, the properties of these new compositions were determined and verified through drop-impact tests. However, these drop tests were expensive and it took a long time to obtain a result. The main goal of this study was to establish an analytical method capable of predicting the impact life-time of a new solder composition for board-level flip chips though the application of drop simulations using LS-DYNA. Based on the reaction load obtain with LS-DYNA, the drop-impact fracture cycles were predicted. The study was performed using a Sn-3.0Ag-0.5Cu solder (305 composition). To verify the reliability of the proposed analytical method, the results of the drop-impact tests and life-time analysis were compared, and were found to be in good agreement. Thus, the new analytical method was shown to be very useful and effective.
Collapse Characteristics of CFRP Hat Member with Outer Laminated Angle Changes under Hygrothermal Environment with Temperature Changes
Yang, Yongjun ; Hwang, Woochae ; Yang, Inyoung ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 243~249
DOI : 10.7735/ksmte.2014.23.3.243
Currently, CFRP composites are rapidly replacing steel plates, as they are lighter, stronger, and more elastic; however, they are poorly suited to hygrothermal and impact-collapsed environments because moisture can alter their molecule arrangement and chemical properties. In this study, environments are experimentally simulated in order to investigate changes in the moisture absorption inside a CFRP composite and to determine its weakest point. Moreover, changes in the moisture absorption ratio at temperatures of
are studied and compared in order to understand how changes in temperature affect moisture absorption inside CFRP composites. Results show that moisture absorption leads to a strength reduction of around 50%. In addition, the moisture absorption rate inside CFRP composites is shown to change rapidly with increasing temperature. Accordingly, it showed that the change in matrix also has a weak point.
Investigation Into the Drilling Characteristics of Carbon Fiber Reinforced Plastic (CFRP) with Variation of the Stacking Sequence Angle
Kim, Tae-Young ; Kim, Ho-Seok ; Shin, Hyung-Gon ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 250~258
DOI : 10.7735/ksmte.2014.23.3.250
Due to recent industrial growth and development, there has been a high demand for light and highly durable materials. Therefore, a variety of new materials has been developed. These new materials include carbon fiber reinforced plastic (CFRP or CRP), which is a wear-, fatigue-, heat-, and corrosion-resistant material. Because of its advantageous properties, CFRP is widely used in diverse fields including sporting goods, electronic parts, and medical supplies, as well as aerospace, automobile, and ship materials. However, this new material has several problems, such as delamination around the inlet and outlet holes at drilling, fiber separation, and tearing on the drilled surface. Moreover, drill chips having a fine particulate shape are harmful to the work environment and engineers` health. In fact, they deeply penetrate into machine tools, causing the reduction of lifespan and performance degradation. In this study, CFRP woven and unidirectional prepregs were formed at
, respectively, in terms of orientation angle. Using a high-speed steel drill and a TiAIN-coated drill, the two materials were tested in three categories: cutting force with respect to RPM and feed speed; shape changes around the input and outlet holes; and the shape of drill chips.
Thermal Behavior of Ventilated Disc Brakes Considering Contact Between Disc and Pad
Ma, Jeong-Beom ; Lee, Bong-Gu ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 259~265
DOI : 10.7735/ksmte.2014.23.3.259
When the brakes of a vehicle are applied, large amounts of heat are generated on the surfaces of the brake discs owing to friction between the discs and the brake pads. A high temperature gradient on the disc surfaces leads to thermal deformation and severe disc abrasion. Ultimately, the thermal deformation and disc wear give rise to a thermal judder phenomenon, which has a major effect on the stability of the vehicle. To investigate and propose a solution to these problems, thermoelastic instabilities under applied thermal and mechanical loads were analyzed using the commercial finite element package ANSYS by considering the contact surfaces between the discs and pads. Direct-contact three-dimensional finite elements between the discs and pads were applied to investigate the disc friction temperature, thermal deformation, and contact stress so that the thermal judder phenomenon on the surface of the disc could be predicted.
Control on the Optical Image Stabilizer Mechanism in Mobile Phone Cameras
Lee, Chibum ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 266~272
DOI : 10.7735/ksmte.2014.23.3.266
This study proposes a closed-loop shaping control method with
optimization for optical image stabilization (OIS) in mobile phone cameras. The image stabilizer is composed of a horizontal stage constrained by ball bearings and actuated by the magnetic force from voice coil motors. The displacement of the stage is measured by Hall effect sensors. From the OIS frequency response experiment, the transfer function models of the stage and Hall effect sensor were identified. The weight functions were determined considering the tracking performance, noise attenuation, and stability with considerable margins. The
optimal controller was executed using closed-loop shaping and limiting the controller order, which should be less than 6 for real-time implementation. The control algorithm was verified experimentally and proved to operate as designed.
Virtual Dynamic Machining System for Chatter Detection and Avoidance
Kim, H. ; Jo, M.H. ; Koo, J.Y. ; Lee, J.H. ; Kim, J.S. ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 273~278
DOI : 10.7735/ksmte.2014.23.3.273
This study presents a chatter vibration avoidance program for the milling process. Chatter vibration has a negative effect on workpieces and spindle-tools. When chatter vibration occurs, the cutting tool is loaded dynamically, a chatter pattern is generated on the workpiece, and the tool life is reduced. The developed program is composed of various modules such as an FFT analyzer, an impact test analyzer, a chatter vibration indicator, and a spindle speed recommender. The proposed program is verified using an AISI D2 cutting experiment in milling process. The effect of chatter vibration on the machining condition can be simulated by the suggested method, and successfully exploited to avoid chatter vibration.
Improvement of Topology Algorithm`s Convergence Rate Using Chaotic Map
Kim, Yong-Ho ; Kim, Gi-Chul ; Lee, Jae-Hwan ; Jang, Hyo-Jae ; Han, Seog-Young ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 279~283
DOI : 10.7735/ksmte.2014.23.3.279
Recently, a topology algorithm based on the artificial bee colony algorithm (ABCA) has been proposed for static and dynamic topology optimization. From the results, the convergence rate of the algorithm was determined to be slightly slow. Therefore, we propose a new search method to improve the convergence rate of the algorithm using a chaotic map. We investigate the effect of the chaotic map on the convergence rate of the algorithm in static and dynamic topology optimization. The chaotic map has been applied to three cases, namely, employ bee search, onlooker bee search, and both employ bee as well as onlooker bee search steps. It is verified that the case in which the logistic function of the chaotic map is applied to both employ bee as well as onlooker bee search steps shows the best dynamic topology optimization, improved by 5.89% compared to ABCA. Therefore, it is expected that the proposed algorithm can effectively be applied to dynamic topology optimization to improve the convergence rate.
Investigation of Cutting Conditions for Stable Machining and Machinability Evaluation in Milling Process of Al7050-T7451 by Response Surface Methodology
Koo, Joon-Young ; Cho, Mun-Ho ; Kim, Hyuk ; Kim, Jeong-Suk ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 284~290
DOI : 10.7735/ksmte.2014.23.3.284
Aluminum alloy is a core material for structural parts of aircraft and automobiles to reduce the weight and maintain high specific strength. This study evaluates the machinability and investigates the optimal cutting conditions considering the surface integrity and productivity for Al7050-T7451 milling. The machining variables considered are the feed per tooth, spindle speed, axial depth of the cut, and radial depth of the cut. The machinability evaluation of Al7050-T7451 is conducted by analyzing the cutting force signals, acceleration signals, AE signals, and machined surface conditions. The optimal cutting conditions are determined by analyzing the experimental results using response surface methodology for stable machining considering the productivity and surface integrity.
Filling Behavior of Polymer Melt in Micro Injection Molding for V-Grooves Pattern
Kim, Moo Sun ; Kim, Seung Mo ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 291~298
DOI : 10.7735/ksmte.2014.23.3.291
This study uses two numerical approaches to analyze the filling behavior of micro patterns on micro-injection molding for V-grooves pattern which cannot be simulated with conventional CAE packages. The parametric studies have been performed to examine the fidelity of micro patterns with respect to temperature, pressure, inlet velocity and pattern location on the mold according to the boundary condition from the macro pressure and velocity data which can be obtained by conventional CAE packages. Through these numerical approaches, the filling behavior of polymer melt in micro patterns can be understood, the quality of replication can be predicted, and the V-groove pattern can be shaped uniformly during the process of injection molding.
A Numerical Study of the Air Quality Inside Automobiles According to the HVAC System Operating Conditions
Yoon, Seonghyun ; Seo, Jinwon ; Choi, Yunho ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 299~309
DOI : 10.7735/ksmte.2014.23.3.299
When using an automotive heating, ventilation, and air conditioning (HVAC) system, we can obtain fresh outside air while maintaining the interior vehicle temperature. In this study, a correction equation considering experimental data for automotive indoor air leakage is defined to simulate the ratio of fresh air to recirculated air in the automobile cabin. With this correction equation, numerical results are compared with experimental data and validated. The
concentration in the automotive cabin is evaluated by considering various boarding conditions and mass flow rates of the HVAC system. The
concentration model derived in this study is expected to be used to control the effective air conditioning and become a basic research tool for automotive air quality control system development.
Verification of Running Safety Evaluation Method for High-speed Railway
Ryu, Sang-Hyun ; Kim, Sang-Soo ; Kim, Dae-Sik ; Kim, Sang-Young ; Hong, June-Hee ; Lee, Ki-Jun ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 310~317
DOI : 10.7735/ksmte.2014.23.3.310
The Next-generation High-speed Rail Technology Development Project was started in 2007 by the Korean Government with the aim of developing the core technologies for a high-speed electric multiple unit (EMU) railway system. This is the first attempt to develop a high-speed EMU railway. High-speed EMU trains have superior acceleration and deceleration compared to push-pull high-speed railways such as KTX(Korean Train eXpress). A prototype train was developed and tested on a high-speed line starting in 2012. The new train must maintain running safety during the test. Generally, the international standard (UIC518) is adopted to evaluate the running safety of trains. This method suggests that the test zone must have over 25 sections, and the length of each section must be 500 m. However, it is difficult to implement these test conditions for a real high-speed line. In this study, we analyzed the running safety using several test section lengths (100 m to 500 m) and compared the results. The results of this study will be used to establish a running safety evaluation method for high-speed EMU railways.
Gain Scheduling in a 6-Axis Articulated Robot Based on LabVIEW
Kim, M.S. ; Chung, W.J. ; Kim, S.B. ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 23, issue 3, 2014, Pages 318~324
DOI : 10.7735/ksmte.2014.23.3.318
Recent years have witnessed a growing demand for a wide variety of high-performance industrial robots. In this paper, for accurate gain tuning of a 6-axis articulated industrial robot with reduced noise, a program routine for a dynamic signal analyzer (DSA) using the frequency response method will be programmed using
. Then, robot transfer functions can be obtained experimentally using the frequency response method with the DSA program. Data from the robot transfer functions are transformed into Bode plots, based on which an optimal gain tuning will be executed. Gain tuning can enhance the response quality of the output signal for a given input signal during real-time control of the robot. The effectiveness of our proposed technique will be verified by implementation with a (lab-manufactured) 6-axis articulated industrial robot (hereinafter called "RS2") and comparison with the zero position gain tuning, as well as other positions.