• 한국해양학회지
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• v.29 no.4
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• pp.357-365
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• 1994

The sediments on the continental shelf off the west coast (middle part) of Korea are divided into northern sandy deposits and southern muddy sediments, respectively. The sandy sediments consist dominantly of quartz and feldspar grains, representing mature-stage sediment in composition. Further-more, the presence of iron-stained quartz grain and glauconite does indicate that the sediments are similar to the relict sediments on the outer shelf of Yellow Sea and East China Sea. These sandy sediments are interpreted as a basal sands that were deposited during the transgression period due to sea-level rise after to last glacial maximum (LGM). The tidal deposits in the Namyang Bay, the west coast of Korea are divided vertically into the upper layer of muddy sediments and the lower layer of sandy sediments. the upper layer sediments contain abundant rock fragments, and are interpreted as the modern tetragenous sediments. The lower layer sediments, on the other hand, are rich in quartz and feldspar grains, representing high index of sediment maturity ratio. the lower layer sandy deposits show the presence of iron-stained.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.70-70
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• 2010

In the present study, to estimate the mechanical properties of 800 MPa grade weld metal, welding was carried out using 800 and 600 MPa grade flux cored arc welding (FCAW) consumable and characteristics of the weld metals were investigated. The chemical composition of weld metals was investigated by an optical emission spectroscopy (OES) method. The microstructure of weld metals was analyzed by optical microscopy (OM) and secondary electron microscopy (SEM). The compositions and sizes of inclusions which are the dominant factors for the nuclei of acicular ferrite were analyzed by an transmission electron microscopy (TEM). In addition, mechanical properties of the weld metals were evaluated through tensile tests and charpy impact tests. Mostly the acicular ferrite phase which has high strength and toughness was observed. The 600 MPa grade weld metal was consisted of 75% acicular ferrite and 25% ferrite which was formed at high temperature (grain boundary ferrite, widmanstatten ferrite, polygonal ferrite). However, the 800 MPa grade weld metal was composed of about 73% acicular ferrite and 27% low temperature phase (bainite, martensite). Toughness was considerably decreased due to the increase of tensile strength (from 600 MPa to 800 MPa). The sizes of inclusions which were observed in both weld metal were $0.4{\sim}0.8\;{\mu}m$, it is effective size to form acicular ferrite.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.10
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• pp.665-670
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• 2016

Prevailing dissemination of machine tools and cutting technology have caused drastic developments of high speed dry machining with work materials of high hardness, and demands on the high-hardness-materials with high efficiency have become increasingly important in terms of productivity, cost reduction, as well as environment-friendly issue. Addition of Si to TiAlN has been known to form nano-composite coating with higher hardness of over 30 GPa and oxidation temperature over $1,000^{\circ}C$. However, it is not easy to add Si to TiAlN by using conventional PVD technologies. Therefore, Ti-Al-Si-N have been prepared by hybrid process of PVD with multiple target sources or PVD combined with PECVD of Si source gas. In this study, a single composite target of Ti-Al-Si was prepared by powder metallurgy of MA (mechanical alloying) and SPS (spark plasma sintering). Properties of he resulting alloying targets were examined. They revealed a microstructure with micro-sized grain of about $1{\sim}5{\mu}m$, and all the elements were distributed homogeneously in the alloying target. Hardness of the Ti-Al-Si-N target was about 1,127 Hv. Thin films of Ti-Al-Si-N were prepared by unbalanced magnetron sputtering method by using the home-made Ti-Al-Si alloying target. Composition of the resulting thin film of Ti-Al-Si-N was almost the same with that of the target. The thin film of Ti-Al-Si-N showed a hardness of 35 GPa and friction coefficient of 0.66.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.511-516
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• 2007

This experiment was conducted to evaluate the effects of differently maturing corn hybrids on silage production and milk production per unit area in the northern part of Japan, where grain development occurs under decreasing ambient temperature. Both hybrids were harvested at the same time. The stages of maturity for the early-maturing hybrids (EH; 80 d relative maturity) and the mid-maturing hybrids (MH; 93 d relative day) were early dent and late dough stage, respectively. The plant yields for MH were higher than those for EH. The dry matter (DM) content of MH was lower than that for EH, and the effluent loss for MH silage was greater than that for EH silage. Therefore, the DM yields of prepared silage per area were similar for both treatments. Twelve multiparous mid-lactation Holstein cows ($58{\pm}13$ days in milk) were fed diets based on EH or MH silage in a crossover design with two 3-week periods. Cows were fed 3 kg of hay crop silage (DM basis) and either EH or MH silage ad libitum, and concentrates were supplied to meet NRC requirement for dairy cows. Silage DM intake for EH was found to be higher (p<0.05) than that for MH (10.0 vs. 9.1 kg/day). Milk production and milk composition for EH were similar to those for MH. Feed efficiency per total feed intake was similar in both treatments, although the feed efficiency per concentrate intake tended to be higher for the EH than that for the MH diet. These results indicate that differences in maturation in corn hybrids affect the effluent production of silage and the silage intake of dairy cows. It may be advantageous to plant early hybrid corn with a reduction in effluent production of silage as well as a reduction in purchased feed costs for dairy cows under the climatic conditions of the northern part of Japan.

• Journal of Nutrition and Health
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• v.32 no.3
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• pp.296-306
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• 1999

This study was carried out to prepare a copper database of Korean foods which can be used in calculating copper intake from dietary data, and to evaluate the copper nutritional status of Koran adults living in rural areas by dietary intake and serum copper concentrations. A copper database for 1,176 Korean foods was constructed (1) by analysing 112 Korean foods which are frequently consumed by Korean adults living in rural areas, (2) by adapting values form food composition databases from other countries-320 items from the University of Minnesota database, 201 items from the USAD database, and 25 items from U.K. database, and (3) by imputing values from similar foods for 518 food items. Copper intake of 2,034 Korean adults over the age of 30 living in Yeonchongun was Kyunggi province, Korea was estimated by 24-hour recall method. Mean daily copper intake of subjects was 0.98mg. Mean daily intake level of males was 1.11mg which was significantly higher than that of females, 0.88mg. There was a significant difference in the distribution of subjects by the level of copper intake and sex(p<0.05). Mean serum copper concentration was 14.8umol/1 and the percentage of subjects with low, adequate, and high levels of copper concentration were 23.9%, 69.4%, and 6.6%, respectively. The two food groups which contributed most to the dietary copper intake of subjects were cereals and grain products, and vegetables, supplying 46.2% and 12.7% of total copper intake, respectively. Individuallym, rice contributed most, suppling 31% of total copper intake, followed by soybean curd, starch vermicle, barley, etc. Plant foods contributed to 82.1% of the total copper intake. In summary, results of this study show that copper intake of Korean adults living in rural areas is low, and that dietary sources of copper are mainly plant foods. Serum levels of copper in the subjects were relatively normal. The copper database for Korean foods constructed in present study will be a valuable tool for the as-yet limited assessment of copper intake of Koreans. Such studies will contribute to the establishment of a dietary of a dietary allowance of copper and the relationship of copper nutriture and chronic diseases in Koreans.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.7
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• pp.980-989
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• 2005

The influence of treated, extruded, partially expelled soybean meals as undegradable protein and bypass fat sources on lactation performance and ruminal fermentation of dairy cows was studied. Experiment 1: nine cows were used in a replicated 3${\times}$3 Latin square design with each period being 3 wk in duration. Cows were fed 440 g/kg forage and 560 g/kg grain diet with one of three extruded soybean meals fed at 110 g/kg of the diet. The 3 soybean meals were 1) twice-extruded soybean meal (ESM; as a control); 2) lignosulfonate-treated, twice-extruded soybean meal (LSM); and 3) calcium oxide plus lignosulfonate-treated, twice extruded soybean meal (CLSM). Experiment 2: 3 ruminally cannulated cows were used in a 3${\times}$3 Latin square to study the treatment influence on ruminal fermentation characteristics. Feeding treated soybean meal to cows in LSM and CLSM treatments did not improve feed intake, milk yield, or milk composition except that cows fed the LSM and CLSM treatments produced less milk protein compared with the ESM treatment. The proportion of $C_{18:2}$ was greater in milk fat of cows fed CLSM compared with that of cows fed the ESM or LSM treatments. Ruminal pH, ammonia, and total volatile fatty acids were not affected by treatment. An increased proportion of $C_{18:2}$ in milk fat suggests that there is a potential use of calcium salts of fatty acids in protecting the lipid portion of extruded soybean meal and further research is needed to explore this potential with full-fat extruded soybeans not with extruded and partially oil expelled soybeans.

• Journal of the Mineralogical Society of Korea
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• v.21 no.1
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• pp.45-56
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• 2008

This study was carried out to determine the effects of mineral composition and grain size of zeolite and bentonite from Po-hang and Kyung-ju, South Korea on the adsorption of heavy metals. Zeolite specimen consists mainly of mordenite, clinoptilolite, heulandite etc. And bentonite specimen is mainly composed of montmorillonite. Five heavy metals, Cd, Cr, Cu, Mn, and Pb were used to conduct the relevant adsorption experiments with the fixed concentrations of 10 ppm and 20 ppm, respectively. Host specimens excluding specimen for Cr resulted in the adsorption rate over average 80 percent, and over 95 percent for Pb. This study indicates that zeolite is more efficient in the adsorption of the heavy metals than bentonite, and its adsorption rate tends to decrease with increasing concentration of the heavy metals.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.420-423
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• 2003

[ $TiO_2$ ] thin films were fabricated by DC magnetron sputtering system at by controlling deposition times, ratios of $Ar:O_2$ partial presser ratio and substrate conditions. And the surface, cross-section morphology, microstructure, and composition ratio of the films were analyzed by FE-SEM, TEM and XPS. Besides, the optical absorption and transmittance of the $TiO_2$ films were measured by a UV-VIS-NIR Spectrophotometer, and photocatalytic properties were studied by G C Analyzer & Data Analysis system. As the result, when $TiO_2$ thin film was made at deposition time of 120[min] and $Ar:O_2$ ratio of 60:40, the best structural and optical properties among many thin films could be accepted. The best results of properties were as follows: thickness; $360{\sim}370[nm]$, grain size; 40[m], gap between two peak binding energy, $5.8{\pm}0.05[eV]$ ($2p_{3/2}$ peak and $2p_{1/2}$ peak of Ti was show at $458.3{\pm}0.05[eV]$ and $464.1{\pm}0.05[eV]$ respectively), binding energy; $530{\pm}0.05\;[eV]$, opticalenergy band gap; 3.4[eV].

• Transactions on Electrical and Electronic Materials
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• v.4 no.1
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• pp.7-10
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• 2003

Single phase CuInS$_2$ thin film with the strongest diffraction peak (112) at diffraction angle (2$\theta$) of 27.7$^{\circ}$ and the second strongest diffraction peak (220) at diffraction angle (2$\theta$) of 46.25$^{\circ}$was well made with chalcopyrite structure at substrate temperature of 70$^{\circ}C$. annealing temperature of 250$^{\circ}C$, annealing time of 60 min. The CuInS$_2$ thin film had the greatest grain size of 1.2 Um when the Cu/In composition ratio of 1.03, where the lattice constant of a and c were 5.60${\AA}$ and 11.12${\AA}$, respectively. The Cu/In stoichiometry of the single-phase CuInS$_2$thin films was from 0.84 to 1.3. The film was p-type when tile Cu/In ratio was above 0.99 and was n-type when the Cu/In was below 0.95. The fundamental absorption wavelength, absorption coefficient and optical band gap of p-type CuInS$_2$ thin film with Cu/In=1.3 were 837nm, 3.OH 104 cm-1 and 1.48 eV, respectively. The fundamental absorption wavelength absorption coefficient and optical energy band gap of n-type CuInS$_2$ thin film with Cu/In=0.84 were 821 nm, 6.0${\times}$10$^4$cm$\^$-1/ and 1.51 eV, respectively.

• The Korean Journal of Community Living Science
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• v.25 no.1
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• pp.89-98
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• 2014

This study was conducted to assess diet-related health appraisal for cardiometabolic diseases of the college students in Gyeonggi-do. The survey data obtained by 21 questionnaire(6 general characteristics and 15 food behaviors) given to 90 students, 41 males and 49 females. The average age of the subjects was 22.2 years old for the male students and 20.9 years old for the female students(p<0.001). Among the subjects, 35 males and 47 females' height, weight and percentage of body fat were measured using bioelectrical impedance(Inbody 720). The average height, weight, Body Mass Index and percent body fat of the subjects were 175.7cm, 69.5kg, 22.4 and 16.9% for males and 162.0cm, 53.5kg, 20.4 and 27.7% for females, respectively (p<0.001). Male students had a higher prevalence of smoking compared with female students(p<0.001). Females had higher intake frequency of fruits than males(p<0.05). Males had higher intake frequency of fishes than females(p<0.05). Male students had higher number of side dishes at mealtime compared with female students. There were no difference between the sexes in intake frequency of dairy, ramyeon, rice with whole grain, 3-layered pork belly, processed meat, soft drinks, soy products and fast food. Also, there were no difference between sexes in number of vegetables per day, frequency of eating out, prevalence of eating kimchi at every meal. Cardiometabolic risks were calculated by 'Diet-related health risk appraisal'. Male students had higher cardiometabolic risks(hypertension, hyperlipidemia, diabetes, obesity, abdominal obesity) than female students(p<0.001). Appropriate nutritional education for college male students may help to prevent cardiometabolic diseases in the future.