• 한국진공학회지
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• 제8권4A호
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• pp.417-424
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• 1999

In order to investigate field emission mechanism of undoped polycrystalline diamond films, diamond films with different structural properties were deposited by varying positive substrate bias and/or $CH_4$ concentration. When increasing $CH_4$ concentration and positive substrate bias voltage, nondiamond carbon content in diamond films increased. Increase of nondiamond carbon content with increasing substrate voltage is ascribed to increase of substrate and excess generation of $CH_n$ radicals. Field emission properties of undoped polycrystalline diamond films ere significantly enhanced with increasing nondiamond carbon content. For diamond films with a small amount of nondiamond carbon, electrons are emitted through diamond surface while for the films with a large amount of nondiamond carbon, electron emission occurs through diamond bulk as well as surface. From this study, depending on nondiamond carbon content two field emission mechanisms were suggested.

• 한국식품영양과학회지
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• 제30권1호
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• pp.107-111
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• 2001

This study was carried out to investigate the effect of Meristotheca papulosa on lipid concentration of serum and liver in rats fed high fat diet for 4 weeks. Experimental groups ere divided into normal group (5% corn oil), high fat diet group (5% corn oil+20% lard), high fat diet and 5% or 10% Meristotheca papulosa treated group. The weights of kidney, heart and tests were not significantly different among the group, but weight of liver was significantly decreased by supplement of Meristotheca papulosa (10%). The contents of serum total lipid, trigly-ceride, total cholesterol, free cholesterol, cholesterol ester and atherogenic index were decreased, while HDL-cholesterol was increased by Meristotheca papulosa supplementation compared to high fat diet group. Meristotheca papulosa supplement has obvious effects on lowering hepatic total lipid, triglyceride and total cholesterol. Our findings suggest that Meristotheca papulosa supplement can improve lipid metabolism in high fat fed rats.

• 복식문화연구
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• 제2권2호
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• pp.355-369
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• 1994

The purpose of this study was to investigate the relationship between the social values and selected clothing behavior variable for a group of working women in Kwang Ju, Chonnam, Korea. The findings of this study as follows: 1. The were differences in selective clothing variables according to their general characteristics; age, marital status, religion. 2. There were differences in selective clothing variables according to their occupational characteristics; type, length of employment, income. 3. A significant relationship was found between he social values and selected clothing behavior variables; There were significant relationship between the social trend and five clothing behavior variables; social approval, psychological dependence, satisfaction, comfort, interest. There ere significant relationship between the human relation and one clothing variables; management. There were significant relationship between the popularization and three clothing behavior variables; social approval, psychological dependence and management.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.679-682
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• 2002

Layered Na0.7[Ni0.05Mn0.95]O2 compounds have been synthesized by a sol-gel method, using glycolic acid as a chelating agent. Na0.7[Ni0.05Mn0.95]O2 precursors w ere used to prepare layered lithium manganese oxides by ion exchange for Na by Li, using LiBr in hexanol. Powder X-ray diffraction shows the layered Na0.7[Ni0.05Mn0.95]O2 has an O3 type structure, which exhibits a large reversible capacity of approximately 190 mA h g-1 in the 2.4-4.5 V range. Na0.7[Ni0.05Mn0.95]O2 powders undergo transformation to spinel during cycling.

• Journal of Plant Biology
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• 제33권4호
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• pp.237-242
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• 1990

Geographical distribution of diploid plant with AA genome (2n=16) and allotetraploid with AABB genome (2n=34) of Scilla scilloides Complex from Korea has been studied. The composition and frequencies of B chromosomes ere also investigated. Plants with AABB genome were predominant over AA genome plants. A mixed population of AA and AABB genome plants was found for the first time. Aneuploid plants have not been found. Chromosomes of AA genome were composed of three pairs of metacentric, two pairs of submetacentric, two pairs of subtlocentric and one pair of telocentric chromosomes, whereas BB genome was four pairs of metacentric and five pairs of subtelocentric chromosomes. B chromosomes were classified into two categories, isochromosome (F) and chromosome fragment (f). The frequencies of B chromosomes were 43% in AA genome plants and 44% in AABB genome plants. The number of B chromosome ranged from 1 to 3 and 1 to 7 in AA and AABB genome plants, respectively. B chromosome combinations were F and F+f in AA genome plants and F, F+f and f in AABB genome plants.

• Natural Product Sciences
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• 제26권2호
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• pp.171-175
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• 2020

Liriodendron tulipifera, belonging to the family Magnoliaceae, is commonly called tulip tree. Four N-acetylated aporphine alkaloids, N-acetylnornuciferine (1), N-acetylanonaine (2), N-acetyl-3-methoxynornuciferine (3), and N-acetyl-3-methoxynornantenine (4) were isolated from the roots of L. tulipifera. Although the purity of each compound (1 - 4) was determined to be 97, 96, 99, and 98%, respectively, the ¹H and ¹³C NMR spectroscopic data of the aporphine alkaloids 1 - 4 displayed all signals in duplicate, indicating the presence of two rotamers due to restricted rotation of N-COCH₃ functionality in solution status. The absolute configurations of 1 - 4 w ere established by measuring specific rotation and comparison with the reported data. This is the first report on the ¹H and ¹³C NMR assignments of N-acetyl-3-methoxynornuciferine (3) and N-acetyl-3-methoxynornantenine (4). This study provides advanced NMR spectroscopic data for the structure determination of rotameric aporphine alkaloids.

• Radiation Oncology Journal
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• 제2권2호
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• pp.177-184
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• 1984

A retrospective analysis of survival data of i2 cases with brain astrocytomas was presented. All patients received post·operative radiotherapy in the period of $1973\~1983$ at YUMC, Yonsei Cancer Center. There were 24 patients with Grade II, 12 patients with Grade III and 16 patients with Grade IV astrocytomas. Survival rates o ere analyzed according to histologic grade of malignancy, age, tumor location, radiation dose and extent of surgical tumor resection. 5year actuarial survival for patients with Grade II astrocytomas was $32.9\%$ and Grade III was $42.9\%$. The 1 year and 2 year survival rate of Grade astrocytomas were $46.7\%$ and $0\%$. Histologic grade of tumor was important prognostic factor in brain astrocytomas. Age and extent of surgical resection were significant prognostic (actors in all grades of astrocytomas and tumor location and radiation dose were significant in Grade f astrocytomas.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.327-332
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• 1997

This study is aimed to investigate the effect of load and deflection on steel fiber reinforced concrete slab. Slabs were made with Hooked and Straight types steel fiber and compared a change of steel fiber contents and fiber types. Test were carried out to evaluate he first crack load, maximum load and deflection of slab. At the result, the first crack load, maximum load and energy absorption capacity were increased remarkably as steel fiber contents wee increased. And we found that the deflection of slab at same load ere decreased as steel fiber contents were increased, too. As the aspect ration was increased, the first crack load, maximum load and energy absorption capacity were increased.

• 한국해양공학회지
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• 제23권1호
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• pp.31-37
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• 2009

Coastal vegetation consists of rooted flowering marine plants that provide a variety of ecosystem services to the coastal areas they colonize. The attenuation of currents and waves and sediment stabilization are often listed among these services. From this point of view, artificial seaweed is an effective method of controlling sea bed sediment and stabilization without damaging the landscape or the stability of the coastline. A series of hydraulic experiments were performed in a wave channel with regular and irregular waves to examine the effect of artificial seaweed in relation to scouring and beach erosion prevention. Based on the results of these experiments, the coastal vegetation model is efficient against scouring and beach erosion.

• 가정과삶의질연구
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• 제3권1호
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• pp.35-49
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• 1985

The Purpose of the study is to identify some factors affecting the consumer behavior of the Oriental students in the United States and provide some basic information for desirable consumer skills. The ninety subjects ere collected form the Oriental groups who were studying in Denton, Texas, U.S.A. Data were analyzed by frequency, percentage, mean, X2-test. The results are as follows: 1) There are significant similarities in the consumer behavior of the Oriental students regarding the information source, the preferred type of clothing, the factors affecting the choice of retail store, and the satisfaction after the clothing purchase. 2) There are some differences in the consumer behavior among three groups regarding expenditures of the purchase of clothing and the preferred choice of retail store. This study concludes that the Oriental students tend to: 1) adjust their life style to new situation ; 2) avoid their conflicts dur to the language barrier; 3) have a limited income to stay in the USA; and 4) have their own social acceptability based on their nationality.