• Journal of the Korean Ceramic Society
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• v.36 no.2
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• pp.178-185
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• 1999

For the process control of silicon nitride gelcasting, the composition effect of acryamide system on the viscosity of slip and mechanical property of gelcast green body were investigated. The slip was prepared by ball milling of silicon nitride suspension prepared with acrylamide monomer and polyelectrolyte dispersant after premixing them by attritor. The slip mixed with initiator was vacuum deaired and cast into molds, and then polymerized. The consolidated green body was obtained by drying the gelated slip. The viscosity measument and the diametral compression test was done to evaluate the rheological behaviro of slip and mechanical property of gelcast body, respectively. Experimental results showed that the high solid loading of silicon nitride slip was obtained up to 46 vol% with a low viscosity. The mechanical property of gelcast body mainly increased with increasing the concentration of monomer. The gelcast body was machinable above the ∼3 MPa of tensile strength. The relative density of pressured-sintered body was 98.5% at 1760$^{\circ}C$, 3 h.

• Archives of Obesity and Metabolism
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• v.1 no.2
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• pp.59-65
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• 2022

Obesity is a serious health concern, which has been linked to an increased risk for cardiovascular diseases and some cancers. The traditional obesity control program is expensive. Moreover, it is difficult to maintain a healthy body weight as well as reduce body fat. The long-term use of effective and tolerable medication is carefully recommended to control body weight. In addition to obesity control medications, health functional foods, related to body weight control, have become popular in the commercial market. Known mechanisms include lipolysis, appetite control, inflammation reduction, and lean body mass maintenance. Previous clinical trials have documented the efficacy of some health functional foods; however, there are limitations. Studies on the potential roles and efficacy of some health functional foods, including caffeine, green tea, protein supplement, probiotics, and arginine, were reviewed. More large-scale and randomized placebo-controlled trials should be conducted eventually.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.72-78
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• 1988

Microstructures of 18 kinds of legume seeds (15 varieties including 3 strains) which were cultivated in tropical areas, were observed under a light microscope. Majority of legume seeds were composed of starchy cotyledonary cells in which large amounts of single starch granules were contained, while a few had cotyledonary cells filled with a number of protain bodies. Starch granules were different in size and shape depending on varieties. Some contained lipid bodies distributed in cytoplasmic network, and were distinctive in thick cell walls. Microstructure of soybean was also observed for the comparison of the structures.

• Journal of Korea Multimedia Society
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• v.19 no.1
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• pp.68-79
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• 2016

Electromyographic (EMG) signals have been widely used as motion commands of prosthetic arms. Although EMG signals contain meaningful information including the movement intentions of human body, it is difficult to predict the subject's motion by analyzing EMG signals in real-time due to the difficulties in extracting motion information from the signals including a lot of noises inherently. In this paper, four Ag/AgCl electrodes are placed on the surface of the subject's major muscles which are in charge of four upper arm movements (wrist flexion, wrist extension, ulnar deviation, finger flexion) to measure EMG signals corresponding to the movements. The measured signals are sampled using DAQ module and clustered sequentially. The Fuzzy C-Means (FCMs) method calculates the center values of the clustered data group. The fuzzy system designed to detect the upper arm movement intention utilizing the center values as input signals shows about 90% success in classifying the movement intentions.

• Journal of the Korean Ceramic Society
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• v.48 no.3
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• pp.228-235
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• 2011

Sintering behavior and lightweight characteristics of porcelain by addition of FAHM (Fly-Ash Hollow Microsphere) were evaluated. Green body of Backja composition (general porcelain) in which FAHM was added(15 and 20 wt%) was made by slip casting method. The green body was sintered at 1270 and $1290^{\circ}C$ and maintained for 1h. The bulk density and linear shrinkage of the sintered body with FAHM (20 wt%) decreased. As the contents of FAHM. increased, mullite and cristobalite phases increased. In the microstructure, FAHM shells remained after sintering, and the generation of mullite fibers around FAHM shells also were confirmed. the weight of porcelain with of 20% FAHM decreased by 40% and residual FAHM shells promoted the mullite of generation in the matrix.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.4
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• pp.66-74
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• 1992

A panel method in the spirit of Hess & Smith(1962), and also of Dawson(1977) was developed to compute the wave resistance of a submerged, or a surface piercing, body moving in the water of finite depth. As a boundary condition on the free surface what is called the Poisson equation is used, while Yasukawa(1989) chose the Dawson equation for which the double-body flow is regarded as the basic one. In order to satisfy the boundary condition on the bottom surface automatically, the sum of a Rankine source and its image with respect to the bottom surface is chosen as the Green function, and hence the singularity is distributed only on the body and on the free surface thereby decreasing the required number of panels dramatically, compared to that of Yasukawa, without the consequential loss of accuracy. Calculations were done for a submerged sphere and for the Wigley hull, and the results are compared with other existing analytical and numerical data.

• Journal of Environmental Science International
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• v.18 no.11
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• pp.1199-1206
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• 2009

Obesity affects various kinds of adult diseases and is a principal cause of injuring people's health. Physical activities are very important to solve the obesity problem and green spaces are good place to take physical activities. In order to examine the utilization of green spaces for physical activities to improve health, the survey was implemented in regards to recognition of health, forms of use of green spaces for physical activities. Only 8.1% of respondents didn't care about health, but 91.9% of them were interested in health more than 'commonness'. 95.2% of respondents knew that obesity has an effect on various adult diseases, and 93.1% of respondents cognized that it's possible to prevent obesity by doing physical activities. More than half of respondents replied that the types of green spaces utilized for physical activities were small-scale neighborhood parks and mini parks around house. About 70% of respondents took walking as a type of physical activities. 53% of respondents utilized green spaces one or two times a week, while 25% of them utilized the places at least three times a week to take physical activities. 91.8% of respondents took exercise for more than 30 minutes. These results are expected to promote health because many experts encourage people to take physical activities at least three times a week because fats of human body begins to bum after 30 minutes from start of physical activities. In the utilizing time of green spaces, evening or after work(56.7%) was higher than morning or before work(35.1%). 71% of respondents usually visited green spaces by walking. This study shows green spaces are good places for physical activities and have boundless potentialities improving people's health.

• Journal of Mushroom
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• v.12 no.4
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• pp.258-262
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• 2014

We aim to elucidate suitable mixed color of light during development of fruit body in Pleurotus ostreatus. The four mixed color of LED(Light Emitting Diode), blue and white, green and white, blue and green and green and red LED, were irradiated for formation of fruit-body. First, as effect of mixed color of LED, the properties of fruit body of P. ostreatus in blue and white LED irradiation were showed higher commercial yields than those in control(fluorescent lamp). And the ergothioneine was the highest at the blue and white LED. Second, we could obtain higher commercial yields than those at the $1{\mu}mol/m^2/s$ of light intensity by blue and white LED in P. ostreatus.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.2
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• pp.248-255
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• 2013

The objective of this study is to optimize the Metal Injection Molding(MIM) process with design of experiments(DOE) and numerical analysis. To derive the optimal process condition, experiment or numerical analysis was performed under various process conditions. To analyze the interaction among influential factors contributing to the temperature at flow front and response surface in MIM, both central point and axial point were added to the full factorial design with 2 levels and 5 factors and then their impacts on response variable in 43 experimental conditions were analyzed and the significance was evaluated. As a result, sprue, runner, and gate were completely filled in about 0.247 seconds after injection, the front part of the green body was filled in about 0.3344 seconds, the green body except gate, etc changed to almost solid state in about 3.29 seconds, the Packinging pressure was completed in about 6.29 seconds, and the green body inside and outside and sprue, etc became solid in 13.2 seconds. The impact of individual or reciprocal action of factors on the temperature at flow front was analyzed through regular probability, test statistics, main effect, and interaction effect. As a result, of a total of 31 combinations of factors, 9 unit factors and reciprocal actions were significant, and the screening was also possible. A proper regression equation was drawn with regression analysis and response surface design on the response variable of temperature at flow front, and the applicability could be verified.

• Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.35-39
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• 2013

The aim of this study was to assess visible implant fluorescent elastomer (VIE) tagging in greenling Hexagrammos otakii. The experiental fish were anesthetized individually and marked with orange, yellow, red, and green elastomer at the following five body locations, respectively: the adipose eyelid, the surface of the dorsal fin base, the inside surface of the pectoral fin base, the inside surface of the pelvic fin base, and the surface of the anal fin base. Control fish were anesthetized but not marked. During the 20-month trial, fish growth and retention, underwater visibility, and readability of the tags were determined. After 20 months, body length of marked greenling ($43.2{\pm}3.5cm$, mean ${\pm}$ standard deviation [SD]) did not differ from that of the control ($41.4{\pm}3.7cm$). Additionally, the body weight of marked greenling ($527.4{\pm}39.8g$, mean ${\pm}$ SD) did not differ from that of the controls ($505.9{\pm}31.7g$). Greenling retained >90% of the tags at the surface of the dorsal fin base. The anal fin base showed a higher tag retention rate than the inside surfaces of the pectoral fin and the pelvic fin bases (P < 0.05). Red and orange tags were identified more easily underwater than green and yellow tags. Green and yellow tags emitted fluorescence in response to a narrower range of light wavelengths. Thus, the VIE mark was easy to apply to greenling (< 1 min per fish) and was readily visible when viewed under an ultraviolet lamp.