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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Transactions of the Korean Society of Mechanical Engineers A
Journal Basic Information
Journal DOI :
The Korean Society of Mechanical Engineers
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Volume & Issues
Volume 39, Issue 12 - Dec 2015
Volume 39, Issue 11 - Nov 2015
Volume 39, Issue 10 - Oct 2015
Volume 39, Issue 9 - Sep 2015
Volume 39, Issue 8 - Aug 2015
Volume 39, Issue 7 - Jul 2015
Volume 39, Issue 6 - Jun 2015
Volume 39, Issue 5 - May 2015
Volume 39, Issue 4 - Apr 2015
Volume 39, Issue 3 - Mar 2015
Volume 39, Issue 2 - Feb 2015
Volume 39, Issue 1 - Jan 2015
Selecting the target year
Statistical Analysis of Experimental Results on Emission Characteristics of Biodiesel Blended Fuel
Yeom, Jeong Kuk ; Yoon, Jeong Hwan ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1199~1206
DOI : 10.3795/KSME-A.2015.39.12.1199
In this study, the exhaust gas of a diesel engine operating on biodiesel(BD) fuel(a mixture of diesel and soybean oil) was investigated for different fuel mixing ratios in the range of BD3 to BD100. The experiments were conducted using injection pressures of 400, 600, 800, 1000, and 1200 bar. The Pearson correlation coefficient and Spearman rank-order correlation coefficient were used to quantify the NOx and Soot emissions based on the fuel mixing ratio and injection pressure. Consequently, the Pearson correlation coefficient obtained for NOx and Soot emissions according to the mixing ratio and injection pressure was -0.811 and the corresponding Spearman rank-order correlation coefficient was -0.884, which indicated that the correlation of the NOx and Soot emissions was linear. Thus, the NOx and Soot have a trade-off relationship. Moreover, at each injection pressure, the Pearson correlation coefficient was a negative number, which indicated an inversely proportional relationship between NOx and Soot.
Evaluation of Fatigue Life of Welded Joint of Gear Box-Shank in Vibro Ripper Using P-S-N Curve
Oh, Kwang Keun ; Kim, JaeHoon ; Park, Jung Yeol ; Yang, GyuSang ; Park, JongWon ; Kim, Sung Hyun ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1207~1212
DOI : 10.3795/KSME-A.2015.39.12.1207
A vibro ripper utilizes high-frequency vibration for rock fragmentation. This concept is different from those used by other existing breakers. The gearbox-shank welded joint of a vibro ripper is a very important part. Because it delivers the vibromotive force to the tooth, it is important to predict its soundness. This study was conducted to predict the fatigue life under welding conditions. The shank materials were Hardox-Hituf and AR400, and the filler metals were CSF-71T and CSF-81T. Fatigue tests were conducted under each set of conditions. P-S-N curves are presented based on the statistical testing method recommended by JSME-S002, and a comparison is made of the results under each set of conditions. The life was estimated using a P-S-N curve.
A Study on the Efficient Flexible Multibody Dynamics Modeling of Deep Seabed Integrated Mining System with Subsystem Synthesis Method
Yun, Hong-Seon ; Kim, Sung-Soo ; Lee, Chang Ho ; Kim, Hyung-Woo ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1213~1220
DOI : 10.3795/KSME-A.2015.39.12.1213
A deep seabed integrated mining system consists of a mining vessel, a lifting pipe, a buffer station, a flexible pipe, and a mining robot for collecting manganese nodules. Recently, the concept of multiple mining robots was introduced to enhance to mining productivity. In this paper, the subsystem synthesis method was applied to the deep seabed integrated mining system in order to improve the efficiency of system analysis and to facilitate its extension to the system of multiple mining robots. Large deflections of the lifting and flexible pipe were considered by dividing a flexible pipe into several substructures, and applying flexible multibody dynamics to each substructure. Theoretical study has been carried out for the efficiency of the subsystem synthesis method for the integrated mining system, by comparing the arithmetic operational counts of the subsystem synthesis method with those of the conventional method.
The Effect of Post-Bond Heat Treatment on Tensile Property of Diffusion Bonded Austenitic Alloys
Hong, Sunghoon ; Kim, Sung Hwan ; Jang, Changheui ; Sah, Injin ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1221~1227
DOI : 10.3795/KSME-A.2015.39.12.1221
Diffusion bonding is the key manufacturing process for the micro-channel type heat exchangers. In this study, austenitic alloys such as Alloy 800HT, Alloy 690, and Alloy 600, were diffusion bonded at various temperatures and the tensile properties were measured up to
. Tensile ductility of diffusion bonded Alloy 800HT was significantly lower than that of base metal at all test temperatures. While, for Alloy 690 and Alloy 600, tensile ductility of diffusion bonded specimens was comparable to that of base metals up to
, above which the ductility became lower. The poor ductility of diffusion bonded specimen could have caused by the incomplete grain boundary migration and precipitates along the bond-line. Application of post-bond heat treatment (PBHT) improved the ductility close to that of base metals up to
. Changes in tensile properties were discussed in view of the microstructure in the diffusion-bonded area.
A Study on Fabrication of 3D Dual Pore Scaffold by Fused Deposition Modeling and Salt-Leaching Method
Shim, Hae-Ri ; Kim, Jong Young ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1229~1235
DOI : 10.3795/KSME-A.2015.39.12.1229
Scaffold fabrication technology using a 3D printer was developed for damaged bone tissue regeneration. A scaffold for bone tissue regeneration application should be biocompatible, biodegradable, and have an adequate mechanical strength. Moreover, the scaffold should have pores of satisfactory quantity and interconnection. In this study, we used the polymer deposition system (PDS) based on fused deposition modeling (FDM) to fabricate a 3D scaffold. The materials used were polycaprolactone (PCL) and alginic acid sodium salt (sodium alginate, SA). The salt-leaching method was used to fabricate dual pores on the 3D scaffold. The 3D scaffold with dual pores was observed using SEM-EDS (scanning electron microscope-energy dispersive spectroscopy) and evaluated through in-vitro tests using MG63 cells.
Optimal Design of Gerotor with Combined Lobe Profiles (Ellipse 1-Elliptical Involute-Ellipse 2)
Kwak, Hyo Seo ; Li, Sheng Huan ; Kim, Chul ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1237~1244
DOI : 10.3795/KSME-A.2015.39.12.1237
A gerotor can be manufactured in a miniature size because it has a high discharge per cycle and a simple structure. Gerotors are widely used for the lubrication oil of an engine and as the hydraulic source of an automatic transmission. Recently, improvements in fuel efficiency and noise reduction have come to the fore in the automobile industry, and it has been necessary for better fuel efficiency to continuously improve the flow rate and noise of internal gear pumps through the optimal design of the gerotor and port shape. In this study, gerotors were generated based on the equations derived for a lobe shape with multiple profiles (ellipse 1-elliptical involute-ellipse 2). The ranges of the design parameters were considered to prevent a cusp and loop. In addition, the optimal lobe shape was obtained by determining the influence of the lobe shape on the performances (flow rate, irregularity, etc.), according to the values of the design parameters.
Diffuse Reflectance Enhancement through Wrinkling of Nanoscale Thin Films
Kim, Yun Young ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1245~1249
DOI : 10.3795/KSME-A.2015.39.12.1245
This study investigated the reflection spectra of wrinkled metal/polymer multilayers. A wavy surface was self-assembled by annealing an aluminum-coated poly(methyl metacrylate) layer on a silicon substrate. The total and diffuse reflectance characteristics of the sample with additional metal coatings(aluminum or silver) were evaluated in the visible wavelength(400~800 nm) using a spectrophotometer. The results showed that the wrinkled surface enhanced the diffuse reflectance up to 40~50% in the lower-wavelength range, demonstrating its potential for applications to optical thin-film devices.
An Experimental Investigation of the Effect of Corrosion on Dry Friction Noise
Baek, Jongsu ; Kang, Jaeyoung ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1251~1256
DOI : 10.3795/KSME-A.2015.39.12.1251
This study investigates the friction noise characteristic in relation to the corrosion of metal by using the frictional reciprocating and pin-on-disk system. From the experiments, it is found that the corrosion of metal advances the onset time and increases the magnitude of friction noise. Further, it is observed that the effect of corrosion on friction noise stems from the alteration of tribo-surface during repetitive frictional motion. The alteration of the corrosive contact surface induces a negative friction-velocity slope, by which the corrosion of metal can generate dynamic instability faster than non-corrosion of metal.
Correlation Between Transient Regime and Steady-State Regime on Creep Crack Growth Behavior of Grade 91 Steel
Park, Jae-Young ; Kim, Woo-Gon ; Ekaputra, I.M.W. ; Kim, Seon-Jin ; Kim, Eung-Seon ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1257~1263
DOI : 10.3795/KSME-A.2015.39.12.1257
A correlation between the transient regime and steady state regime on the creep crack growth (CCG) for Grade 91 steel, which is used as the structural material for the Gen-IV reactor systems, was investigated. A series of CCG tests were performed using 1/2" CT specimens under a constant applied load and at a constant temperature of
. The CCG rates for the transient and steady state regimes were obtained in terms of
parameter. The transient CCG rate had a close correlation with the steady-state CCG rate, as the slope of the transient CCG data was very similar to that of the steady state data. The transient rate was slower by 5.6 times as compared to the steady state rate. It can be inferred that the steady state CCG rate, which is required for long-time tests, can be predicted from the transient CCG rate obtained from short-time tests.
A Study on Structural Safety of the Boom Hoisting Cylinder of a Coal Handling Machine
Choi, Yong Hoon ; Kwak, Hyo Seo ; Kim, Chul ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1265~1273
DOI : 10.3795/KSME-A.2015.39.12.1265
A coal handling machine is a type of equipment used for loading coal, the main material in a steam power plant, along a conveyer belt from a ship, and is placed after the driving chain bucket. However, studies on the boom hoisting cylinder, which is a hydraulic system used to control the angle of the boom based on loading location, indicate that domestic models are insufficient, and are thereby often substituted with a foreign product. In this study, a technique for analyzing the contact pressure in a thick-walled cylinder was established by comparing the contact pressure, which is calculated theoretically based on the results obtained from FEM simulation, and by checking whether the working oil is leaking from the boom hoisting cylinder using a v-seal. In addition, the driving motion was simulated according to the strokes of the cylinder, and the structural stability was verified under the maximum output conditions.
Development of the Accelerated Life Test Method & Life Test Equipment for the Counterweight of the Construction Machinery
Lee, Gi-Chun ; Lee, Young-Bum ; Choi, Byung-Oh ; Kang, Bo-Sik ; Kim, Do-Sik ; Choi, Jong-Sik ; Kim, Jae-Hoon ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1275~1280
DOI : 10.3795/KSME-A.2015.39.12.1275
A large-sized exciter that vibrates a two-ton component is required to simulate the field operating conditions of a counterweight of an excavator. However, it is difficult for a small-medium sized company to obtain a large exciter for the life test of a counterweight which is an equivalent counterbalancing weight that balances a load. Therefore, in this study, we developed life test equipment for evaluating the reliability of construction machinery weighing about two tons. It simulates the field operating conditions using rotational vibrators consisting of electric motors. A failure analysis of the counterweight was also performed for the major components. Field data acquired from various sites were applied to the life test design of the counterweight. Finally, a zero-failure qualification test based on the accelerated life test was designed, and there was no failure during the test, which guarantees a life of
Stress Spectrum Algorithm Development for Fatigue Crack Growth Analysis and Experiment for Aircraft Wing Structure
Chun, Young Chal ; Jang, Yun Jung ; Chung, Tae Jin ; Kang, Ki Weon ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1281~1286
DOI : 10.3795/KSME-A.2015.39.12.1281
Fatigue cracks can be generated in aircraft as a result of the cumulative time spent during flight operations, which can extend for long periods of time and cover a variety of missions. If a crack occurs in an aircraft`s main spar, it can generate many problems, including a lift time reduction. To solve this problem, it was necessary to perform an analysis of fatigue crack growth in the fatigue critical locations. Much time and expense is involved in generating the stress needed for a crack propagation analysis over a long period of time to obtain the amount of data required for an actual aircraft. In this paper, an algorithm is developed that can calculate the spectrum of stress over a long period of time for a mission by the Southwest Research Institute, which is based on the short-time load factor data produced using the peak-valley cycle counting method.
Implementation of CiA 406 Device Profile for CANopen Compatible Encoders
Hwang, Hyunbum ; Ahn, Hyosung ; Kim, Sanghyun ; Kim, Taehyoun ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1287~1295
DOI : 10.3795/KSME-A.2015.39.12.1287
Recently, fieldbus communication technologies have been widely deployed for industrial automation because they are profitable in providing easy system integration and management for multiple devices, as well as high-speed communication. It is essential for smart encoders to support fieldbus connectivity, where the device configuration and various types of information related to position are exchanged between an external controller and multiple encoders over the communication link. In this study, we implemented the CiA 406 device profile for smart encoders from the CANopen standards by extending an open-source CANopen standard-compliant framework, called CanFestival. The CiA 406 functionalities implemented in this study were validated on a test-bed consisting of a CANopen master and virtual CANopen encoders with our CiA 406 extension module.
Study On Effect of Fe Density on Electrolyte Exfoliation of Chromium Plating Layer
Park, Jin-Saeng ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1297~1303
DOI : 10.3795/KSME-A.2015.39.12.1297
The internal chromium plating of a long-axis tube is widely used in military and industrial application, with the thick hard plating formed using a mixed solution of Chromium acid and catalytic
. A large-caliber gun can endure a high explosive force as a result of the increased stiffness and wear resistance provided by this internal hard chromium surface. The internal chromium layer of a tube is prone to exfoliation caused by the high kinetic energy of the projectile and high pressure of the explosion. Therefore, we reviewed the plating process. Chromium plating comprises many steps, including the removal of Grease, water cleaning, electrolytic abrasion, etching, plating, water cleaning, and hydrogen brittleness removal. The exfoliated chromium plating layer is affected by the adhesion property of the plating. In particular, the Fe concentration of the electrolyte affects the adhesion property. The optimum Fe concentration for effectively suppressing the exfoliation of the plating layer was established by using a scanning electron microscope to determine the surface roughness, and the effectiveness was proved in an adhesion test, etc.
Reliability Evaluation of Concentric Butterfly Valve Using Statistical Hypothesis Test
Chang, Mu-Seong ; Choi, Jong-Sik ; Choi, Byung-Oh ; Kim, Do-Sik ;
Transactions of the Korean Society of Mechanical Engineers A, volume 39, issue 12, 2015, Pages 1305~1311
DOI : 10.3795/KSME-A.2015.39.12.1305
A butterfly valve is a type of flow-control device typically used to regulate a fluid flow. This paper presents an estimation of the shape parameter of the Weibull distribution, characteristic life, and
life for a concentric butterfly valve based on a statistical analysis of the reliability test data taken before and after the valve improvement. The difference in the shape and scale parameters between the existing and improved valves is reviewed using a statistical hypothesis test. The test results indicate that the shape parameter of the improved valve is similar to that of the existing valve, and that the scale parameter of the improved valve is found to have increased. These analysis results are particularly useful for a reliability qualification test and the determination of the service life cycles.