• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3
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• pp.372-379
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• 2013

In this study, we investigated the traits of the clad metals used in hot-rolled clad steel plates. We examined the sensitization and mechanical properties of STS 316 steel plate and carbon steel (A516) under the specific circumstances of post heat treatment and whether a weld was multilayered and thick or repeated because of repairs. The test conditions were as follows. The clad steel plates were butt-welded using FCAW/SAW, and the heat treatment was conducted at $625^{\circ}C$, for 80, 160, 320, 640, or 1280 min. The change in the corrosion resistance was evaluated in these specimens. In the case of the carbon steel (A516), as the heat treatment time increased, the annealing effect caused the tensile strength to decrease. The micro- hardness gradually increased and then decreased after 640 min. The elongation and contraction of the area increased gradually. An oxalic acid etch test and EPR test on STS316, a clad metal, showed a STEP structure and no sensitization. From the test results for the multi-layered and repair welds, it could be concluded that there is no effect on the corrosion resistance of clad metals. In summary, the purpose of this study was to suggest some considerations when developing on-site techniques and evaluate the sensitization of stainless steels.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.4
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• pp.44-49
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• 2011

The crawler crane, which consists of a lattice boom, a driving system, and movable vehicle, is widely used in a construction site. It needs to be installed an overload limiter to prevent the overturning accident and the fracture of structure. This research is undertaken to provide the relation formula for designing the overload limiter as follows: First the relation formulas between the wire-rope tension and the hoisting load or the overturning ratio according to the luffing angle and length of a lattice boom are established. Secondly the derived formulas are corrected by using the compensated angle considering the deflection of boom through the finite element analysis. The stiffness analysis is carried out for 30-kinds of models as a combination of 6-kinds of luffing angle and 5-kinds of length of boom. Finally the shape design of a stick type load cell, which is the device to measure the wire-rope tension, is performed. 5-kinds of notch radius and 5-kinds of center hole radius are adopted as the design parameter for the strength analysis of the load cell.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.5
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• pp.667-671
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• 2010

The study was aimed at developing a power transmission coupling that is possible to transfer power without any trouble even if the two rotating shafts are making minute misalignment. The coupling that has been developed is Flange Flexible Urethane-key Coupling that connects two shafts by flanges with Urethane-key. A model coupling for use in transmitting power of 10hp was made and undergone performance evaluation and tests. Property and usefulness was proved through the test. The performance evaluation has demonstrated a property of $11.25Kgf{\cdot}m$ of allowable torque and 28.25hp of power at 1,80Orpm, which was found to be superior compared to the performance of similar couplings. Based on the performance test, study was made also for improving the shape of the Urethane-key and was successful to make the flange in smaller outside diameter. Further application test at site has proved that the product is easy to install and maintain, and has property of absorbing minute misalignment between two shafts and vibration caused there from.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.16 no.1
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• pp.117-124
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• 2020

3D printing is a technology that has significantly grown in recent years, particularly in the aerospace, defense, and medical sectors where it offers significant potential cost savings and reduction of the supply chain by allowing parts to be manufactured on-site rather than at a distance supplier. In nuclear industry, 3D printing technology should be applied according to the manufacturing trend change. For the application of 3D printing technology to the nuclear power plant, several problems, including the absence of code & standards of materials, processes and testing & inspection methods etc, should be solved. Preemptively, the improvement of reliability of 3D printing technology, including mechanical properties, structural performance, service performance and aging degradation of 3D printed parts should be supported. These results can be achieved by collaboration of many organizations such as institute, 3D printer manufacturer, metal powder supplier, nuclear part manufacturer, standard developing organization, and nuclear utility.

• Journal of Mechanical Science and Technology
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• v.14 no.4
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• pp.380-392
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• 2000

A typical production-distribution system consist of three main echelons representing the retailer, distributors, and a factory each with an on-site warehouse. The system is sufficiently general and realistic to represent many industrial situations. However, decision functions and parameters have been selected to apply particularly to the production and distribution of consumer durables. The flows included in the model are materials, orders, and those information flows needed to support the material and order-rate decisions. In this work, a realistic production-distribution system has been used as a basic model, which consists of three sectors: retailer, distributor, and factory. That system is a nonlinear 25th-order continuous system interconnected between the echelons. Using a modern control algorithm, a typical multi-echelon production-distribution system using a dynamic controller is numerically simulated in the nominal plant and in the perturbed plant when the piecewise constant manufacturing decision is limited by a factory manufacturing upper-limit due to capital equipment, manpower, and factory lotsize.

• CDE review
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• v.4 no.3
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• pp.26-31
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• 1998

Recent trend of popularity of CAE(Computer Aided Engineering) tools and its availability, partly contributed by significant price reduction of H/W and SW, makes us believe CAE has already established terra firma as de jure tools, enablint the design improvement in the manufacturing am. However, if your jobs are required to be working closely with engineers located in the front line of manufacturing site, CAE is observed far from popularity, still being regarded as exclusive tools for engineers holding advanced degrees. Conventional methodologies depending on knowledge that was accumulated thorough trial and errors, depending primarily on engineering tables and formulas or proprietary know-how, are preferred as the de factor standard under the roof of contemporary development shops. Samsung camera, having stared its business since early 、80, has accumulated enough technological strength to compete in the world market. As today's consumers demand more sophisticated featured-lighter weight, built-in multi zoom and miniature size fitting in the palm-from camera manufacturer, so should Samsung camera respond to ever-delicate consumer's needs with great flexibility. Consequently conventional designers, without sophisticated analytical tools, with encounter solving the critical design factors that have never been treated as seriousness-marginal safety factors induced by reduced size of parts. In the study, CAE results of boss and gears were demonstrated as examples, which confirms the facts that the simple analysis done by front line designers, can bring distinguishable effects on the potential improvements of design and on the consequential influences on the future design process-simulation before actual tooling and productions.

• The Research Journal of the Costume Culture
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• v.12 no.5
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• pp.691-701
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• 2004

The first purpose of this study was to compare the factors of information searching before purchasing with the factors of information offering after purchasing of the products, which were communication contents about the wedding Hanbok in internet communities. The second purpose was to propose marketing strategies for internet wedding Hanbok marketer. To accomplish the goal, the content analysis method which considered references and opinions of internet community members was used. Two hundred cases from WEDDING CLUB(62,893members), WEDDING GONGBU (18,649members), and WEDDING DOUMI (17,326members) in Daum internet portal site were selected from August 1 to September 21, 2003. The results were as follows: First, the information factors which were considered seriously when consumers purchased wedding Hanbok, were design, the level of sewing, price, store location, cognitive power, service level, and manufacturing time. Second, the consumers considered the price as the most important factor when they searched internet information. Third, the service factor was also considered importantly, and it was recognized important factor so much after purchasing as before purchasing wedding Hanbok. Fourth, the factors such as cognitive power, manufacturing time and store location were seriously considered as the information searching factors before purchasing. It showed higher rate when compared with information offering factors of after purchasing the wedding Hanbok. Fifth, the factor of sewing was considered as lower rate than other factors. It showed similar results before and after purchasing the wedding Hanbok.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.4
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• pp.89-96
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• 2017

A cable tray is a structure made of metal or a non-combustible material that supports cables in the electrical wiring of buildings. Cable trays should be developed to meet the various requirements of the construction site. In this study, a design system was developed to calculate the maximum support load and the maximum deflection according to the cross-sectional shape of the cable tray. The cross-sections of cable trays were modeled by combining linear and arc elements, and cross-sectional characteristics such as the 2nd moment of area were calculated. The distributed load and the concentrated load were applied to the cable tray using the Euler beam theory, and then the deflection profiles and maximum stress were calculated. To verify the developed system, deflection distributions and maximum stresses for two types of cable trays were calculated and compared. The maximum deflection and maximum stress errors calculated from the developed system were found to be less than 4% compared with numerical analysis results.

• 보존과학연구
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• s.27
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• pp.83-102
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• 2006

The Suchon-ri tomb No. 1 is the earliest one among the Suchon-ri tombs excavated in 2003. The Suchon-ri tomb No. 1 yielded a number of valuable artifacts furnished with burial goods such as gilt bronze items of a crown, a pair of earrings and shoes and a loop-handled sword with inlaid silver decoration. In particular, a loop-handled sword drew scholarly attention in that it showed characteristics of Baekje such as wave patterns on a silver plate decorated in the handle and sheath and inlaid dragon design on the loop-handle. In the process of the reproducing the loop-handled sword, classification methods of the loop-handled swords, iconography decorated on the swords, unearthed loop-handled swords of the Three Kingdoms Period have been investigated along with studying the reproduction cases in Japan. In addition to the study focused on the shape of the swords, manufacturing techniques have been thoroughly analyzed through scientific methods. Finally, based on the synthesis of a series of studies and analyses, traditional manufacturing techniques employed by Baekje artisans had been inferred and a replica of the loop-handled sword was manufactured with the traditional methods.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.6
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• pp.95-100
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• 2017

Recently, biomedical-grade texture material gauze has often been used to treat wounds. At this time, it is difficult to remove scratches and pushed gauze; if you remove it with force, the tissue may separate and bleeding may occur again. In this study, we studied a method to apply medical-grade silicone material. Similar to the research result that hypertrophic wounds reduce the thickness of scar marks. Through mini-pig experiments, we evaluated the effects on scar treatment. The test results showed that the silicone cover layer applied to the wound site had a sealing effect on the wound area, skin temperature, and histopathological examination. In conclusion, gel treatment utilizing a biocompatible substance had the effect of minimizing hypertrophic scars.