• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.4
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• pp.929-940
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• 1995

The fatigue strength and fracture topography in the friction welded interface of high speed steel (HSS-Co) to SM55C carbon steel have been investigated through the fatigue test, SEM fractograph and EDS (energy dispersive spectrometer) analysis. Three kinds of specimens used in this research are the friction welded joints, HSS-Co and SM55C carbon steel with circumferential notch, saw notch and smooth, respectively. The notch sensitivity factor, .eta. of the friction welded joints is lower than that of the base materials, and that represents a superiority of the joint performance of FRW. Fracture topography of the FRW specimens with a notch showed a cleavage or brittle appearance, while that of the FRW smooth specimen appeared to be ductile. Furthermore, although fatigue crack likely initiated near the weld interface of the FRW smooth specimen, crack propagation continued into the HAZ of SM55C steel. Finally, fatigue fractures of the base materials were associated primarily with the inclusions located at the outer periphery of the specimen.

• Food Science and Preservation
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• v.12 no.3
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• pp.252-256
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• 2005

For increasing shelf-life, melons with different washing and packaging were evaluated during storage at room temperature. Hardness and weight of melon was decreased during storage period and, after 12 days, severe rotten or decay appeared on melons except melon with ozone-water. Organoleptic test on color, appearance, taste and texture showed maximum values on melons eith ozone-water washing. Particularly, spots have been shown on all packaged melons in the later storage, except melons washed with ozone-water. According to these results, ozone-water washing was effective for keeping the high quality of melons.

• Journal of the Korean Society of Costume
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• v.50 no.7
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• pp.155-163
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• 2000

The objectives of this study were to examine how clothing design preference and clothing attitude vary according to gender of the aging. Using the data collected through interview with 200 subjects who were 60years of age and older residing at Kunsan city area in Korea. These data were analyzed by frequency and $\chi$$^2$-test. The tendency of the gender on jacket stymie preference showed that men liked the soutien collar jacket, two button sing1e Jacket, and four button double jacket, women liked two button single jacket, three button single Jacket and four button double jacket. The general preference did allot depend on the practical purchasing. Men preferred more the soutien collar jacket than the women. On the shirts pattern preference, men liked thick horizon and plaid pattern, while the women liked polk dots pattern and small flowered one. The practical clothing purchase was done by themselves directly. The important criteria depended on the appearance style like simple and smart. For the main complaining factor to purchase the clothes, men considered the color, and women complained not to have suitable shopping stores. The most of all complaining was the expensive prices.

• The korean journal of orthodontics
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• v.22 no.4 s.39
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• pp.855-868
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• 1992

This study was designed to test the possibility of using a standardized lateral facial photographs as a clinical tool which produce the prediction of postsurgical soft-tissue profile changes associated with surgical correction in skeletal CIII patients. The number of the patients involved in this study were 27 in total, including 11 male patients and 16 female patients. A practical method to the utilization of presurgical photo prediction for mandibular prognathic patients has been presented. To predict postoperative facial appearance, montage photographs were superimposed on standard facial reference photos taken preoperatively. Within the limitations of its technology, postoperative predictions generated by this method were of sufficient accuracy, especially mandible and chin area, for clinical use. In addition, they provide valuable communication and diagnostic information which may be used in formulating treatment plan in cases requiring corrective orthognathic surgery. But, the lip changes were somewhat exaggerated by photo prediction. Consequently, the photo prediction seems suitable for planning profile changes in orthognathic surgery that include mobilization of one main mandibular fragment. Futher investigations are needed to determine whether changes of soft-tissues and hard-tissues are sufficiently reproducible so that more meaningful predictive values can be established.

• International Journal of Fluid Machinery and Systems
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• v.10 no.2
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• pp.164-175
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• 2017

Francis turbines are often operated over a wide load range due to high flexibility in electricity demand and penetration of other renewable energies. This has raised significant concerns about the existing designing criteria. Hydraulic turbines are not designed to withstand large dynamic pressure loadings on the stationary and rotating parts during such conditions. Previous investigations on transient operating conditions of turbine were mainly focused on the pressure fluctuations due to the rotor-stator interaction. This study characterizes the synchronous and asynchronous pressure and velocity fluctuations due to rotor-stator interaction and rotating vortex rope during load variation, i.e. best efficiency point to part load and vice versa. The measurements were performed on the Francis-99 test case. The repeatability of the measurements was estimated by providing similar movement to guide vanes twenty times for both load rejection and load acceptance operations. Synchronized two dimensional particle image velocimetry and pressure measurements were performed to investigate the dominant frequencies of fluctuations, vortex rope formation, and modes (rotating and plunging) of the rotating vortex rope. The time of appearance and disappearance of rotating and plunging modes of vortex rope was investigated simultaneously in the pressure and velocity data. The asynchronous mode was observed to dominate over the synchronous mode in both velocity and pressure measurements.

• Fashion & Textile Research Journal
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• v.21 no.6
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• pp.776-788
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• 2019

This study developed an ergonomic Korean female military winter jacket and (inner and outer) pattern in in order to increase dimension and operational suitability for military missions. First we developed the 1st development pattern and sample jackets with improved dimensions and operational suitability based on a previous investigation of fitness and motion suitability of Korean female military winter jackets (inner and outer) and motion suitability by a wearing test. The evaluation result of fitness for the 1st development pattern were over 4.0 (5.0 Likert scale) for both the inner and outer jacket, a positive result and the result of motion suitability were over 3.5 in both the inner and outer jacket except for the neck front part by collar height. However, we did not modify the collar height because decreases in warmth and military regulations. We also evaluated appearance by experts that showed good results in both the inner and outer jacket. Finally, we developed a final pattern based on evaluation results and military regulations. Existing military uniform research was conducted mainly on male soldiers. Beginning with this study, we expect to expand research on the development of military uniform patterns suitable for a female soldier body type.

• Korean Journal of Pharmacognosy
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• v.50 no.4
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• pp.318-323
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• 2019

This study was designed to establish the stability of EGHB010, a combined hot water extract of Paeoniae Radix and Glycyrrhizae Radix. Test of coliform groups, sensory evaluations, contents of moisture, and the amount of paeoniflorin and glycyrrhizin were determined during storage at 4, 25 and 35℃ for 6 months. Coliform groups were not observed and moisture contents were maintained about 3.0% during the storage period. Sensory characteristics including color, taste, texture and appearance were tested over 3 points throughout the entire storage period. It maintained the commercial value during the storage period. Contents of paeoniflorin and glycyrrhizin as indicator components were remained stably for the storage period. The shelf-life of EGHB010 based on a linear response to zero of sensory evaluation with the highest correlation coefficient was predicted. Finally, the shelf-life of EGHB010 was expected for about 3 years to consider in safety coefficient. The shelf-life data of EGHB010 can be used to develop a functional health ingredient.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.88-97
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• 2009

The vacuum die casting techniques can diminish the porosity of products and provide better surface appearance by the ordinary high pressure die casting process. The vacuum system can also reduce the cold laps in the die casting process and minimize the overflow pockets of the die. The vacuum system does not need high pressures to die cast compared to the ordinary die casting process, and so enables die casting of large parts for a given machine size. Parts made by the vacuum system have higher strength and more elongation than parts made by the ordinary die casting systems. In this paper, we designed and produced the Magnesium seat frames using the vacuum die casting processes. The new Magnesium seat frame was designed to satisfy safety regulations. Some safety test procedures of the seat frame were simulated by the finite element method. We obtained 10% weight reduction by design modification of seat frames compared to the current model. Flow simulations were carried out to minimize the trial and error in producing the parts. The die casted parts using vacuum systems resulted in better mechanical characteristics and no defects compared to those without vacuum systems.

• Journal of Korean Society of Steel Construction
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• v.22 no.1
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• pp.75-85
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• 2010

A new freeform structure representing "Diagrid, Cantilevered, Tilted." which has been considered not only its distinctive appearance but also the structural advantages becomes one of the trends in tall building design. Especially in the Diagrid system, loads can be distributed through bracing frame so that it can be save the materials since it has more effective in the structure behavior. But the seismic performance index such as response modification factor is not clearly defined yet. Even though the diagrid is supposed to show higher seismic performance, it is underestimated due to the lack of reliable data. In this paper the response modification factor for the diagrid system is experimentally explored.

• Journal of the Korean Wood Science and Technology
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• v.24 no.4
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• pp.15-21
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• 1996

This study was carried out to investigate the making method and properties of Hanji(Korean traditional paper) for wallpaper for the purpose of mass production and mass consumption of Hanji. Paper mulberry fiber was longer than wood fiber in length and it had also much extractives and ash in content. Bast fiber was a little damaged in the fibrilation and beating process because it was weak in flexibility and compressive properties. Proper conditions for making two-ply and three-ply Hanji were examined and six kinds of Hanji were made on the basis of the three-ply paper making method. The sample OH(Original Hanji) 2-2 and OH 3-2 among them obtained good results in quality test by appearance from wallpaper makers.