• Korean Journal of Materials Research
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• v.6 no.12
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• pp.1221-1232
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• 1996

용접부 인성을 향상시키기 위해 Ti 산화물을 첨가한 Ti 산화물강에 대하여 용접시 최고가 열온도와 냉각속도의 변화가 용접열영향부의 미세조직에 미치는 영향을 조사하였다. 용접열영향부의 인성향상에 기여하는 acicular ferrite는 140$0^{\circ}C$ 이상의 최고가열온도와 $\Delta$t800-500가 40초보다 빠른 냉각속도에서 활발해 생성되었다. 오스테나이트 결정립내에서 개재물로부터 핵생성된 일차 acicular ferite의 생성량은 전체 aicular ferrite의 약 20% 정도로 적었으며 대부분의 acicular ferrite는 일차 acicular ferrite로부터 생성된 이차 acicular ferrite인 것으로 나타났다. 이차 acicular ferrite는 plate사이에 Fe3C층이 존재하는 것으로 보아 확산기구에 의해 생성되는 것으로 생각된다. 개재물은 TiO, TiO2, TiN, MnS, AI2O3 MnO(galaxite)등으로 구성된 복합상이었으며 개재물이 일차 acicular ferrite의 핵생성 site로 작용하기 위해서는 약 1$\mu\textrm{m}$이상의 크기가 효과적인 것으로 나타났다. Ti 산화물과 TiN는 직접적인 acicular ferrite의 핵생성 site로 작용하기보다는 MnS, galaxite 등의 석출 site로 작용하여 개재물의 크기를 증가시킴으로써 acicular ferrite의 생성을 촉진시키는 것으로 생각된다.

• Journal of the Korean Society for Heat Treatment
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• v.13 no.4
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• pp.224-230
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• 2000

Garbon steel(SM35C) was gas nitrocarburized at $580^{\circ}C$ in $55%N_2-40%NH_3-5%CO_2$ mixed gas atmosphere, and then the steel was induction hardened at $850^{\circ}C$. The microstructure of gas nitrocarburized surface layer was observed by optical microscope and SEM. The phase analysis was carried out by X-ray diffraction method. The mechanical properties of gas nitrocarburized SM35C steel was evaluated by hardness, wear and fatigue test. The thickness of compound and diffusion layer were increased with increasing the gas nitrocarburizing time and the densest compound layer was obtained at 3 hours gas nitrocarburizing time. In case of 15sec induction hardening after gas nitrocarburizing, the surface hardness was decreased from 800Hv to 630Hv owing to the decomposition of compound layer, but wear resistance was increased because of increased hardness of diffusion layer. The fatigue strength of induction hardened steel after gas nitrocarburizing, $58kgf/mm^2$, was higher than $41.5kg/mm^2$ of gas nitrocarburized steel and $45kg/mm^2$ of induction hardened steel, respectively.

• Journal of Families and Better Life
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• v.26 no.3
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• pp.169-189
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• 2008

There are few studies on the characteristics of defaulters, though research in this field is needed. The purpose of this study was to find out social, economic and psychological characteristics of defaulters who are married and in their thirties. For this study, an in-depth interview was used. The major findings were as follows. The focus of this study is defaulters who are married, in their thirties, have managed small businesses by themselves or with their spouses and have experienced job fluctuation. There were a lot of reasons for their becoming defaulters. Most of all, a slump in business with the occurrence of individual events caused them to be enrolled as defaulters. The monthly mean income of defaulters was $1,800,000{\sim}5,000,000$ won, yet it was irregular. Moreover, they were dependent upon labor income or business income. The monthly mean expenditure of defaulters was $1,000,000{\sim}2,300,000$ won, which constituted about $26%{\sim}57.5%$ of their monthly mean income. The defaulters needed to budget a number of expenditures such as food and private education. Defaulters had $25,000,000{\sim}128,000,000$ won in debts and $300,000{\sim}3,000,000$ won per month in debt payments. Most of them didn't have any emergency funds, monetary assets or fixed assets. Interestingly, they showed high tendency to use debt and low skill for their money management. Defaulters had short time horizons and were likely to buy something on the spur of the moment.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.49-55
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• 1984

Dormant one-year-old ginseng roots were subjected to a range of stratification temperatures and time to define effective limits to these parameters and to quantify their effect on terminating dormancy. Effective storage temperatures tested ranged from $0^{\circ}C\;to\;9^{\circ}C.$ A low percentage of roots produced tops with as few as 30 days in stratification; however, 75 to 90 days were required for 100 percent emergence. Days to emergence, after planting, decreased with increased days in storage thru the maximum storage time of 120 days. The number of days of dormancy was relatively constant, near 126.5 days, over the range of effective temperatures and acceptable storage times. The minimum period of dormancy was associated with 75 days in storage at $3^{\circ}C.$ Root growth rate, after emergence, was greatest following 105 days of stratification. The frequency distribution of emergence with days in stratification suggests the potential of selecting for strains of ginseng with low chilling needs for satisfying dormancy requirements.

• Corrosion Science and Technology
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• v.11 no.1
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• pp.9-14
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• 2012

The formation of the Fe-Al inhibition layer in hot-dip galvanizing is a confusing issue for a long time. This study presents a characterization result on the inhibition layer formed on C-Mn-Cr and C-Mn-Si dual-phase steels after a short time galvanizing. The samples were annealed at $800^{\circ}C$ for 60 s in $N_{2}$-10% $H_{2}$ atmosphere with a dew point of $-30^{\circ}C$, and were then galvanized in a bath containing 0.2 %Al. X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) was employed for characterization. The TEM electron diffraction shows that only $Fe_{2}Al_{5}$ intermetallic phase was formed. No orientation relationship between the $Fe_{2}Al_{5}$ phase and the steel substrate could be identified. Two peaks of Al 2p photoelectrons, one from metallic aluminum and the other from $Al^{3+}$ ions, were detected in the inhibition layer, indicating that the layer is in fact a mixture of $Fe_{2}Al_{5}$ and $Al_{2}O_{3}$. TEM/EDS analysis verifies the existence of $Al_{2}O_{3}$ in the boundaries of $Fe_{2}Al_{5}$ grains. The nucleation of $Fe_{2}Al_{5}$ and the reduction of the surface oxide probably proceeded concurrently on galvanizing, and the residual oxides prohibited the heteroepitaxial growth of $Fe_{2}Al_{5}$.

• The Journal of Korean Medicine
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• v.38 no.3
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• pp.111-123
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• 2017

Objectives: To develop and investigate the reliability of the pathologic aging scale based on korean medical theory and korean medical pattern identification for dementia. Methods: We searched the textbook of korean neurophychiatry and Donguibogam and selected items through professional consensus. We compared between dementia(n=40) and normal elderly(n=38) and tested the reliability of two scales. Results: After professional consensus, we drafted the Korean Medical Pathologic Aging Scale(12 items, Likert 3 scale) and Korean Medical Pattern Identification for Dementia(4 patterns, 28 items, Likert 5 scale). On Korean Medical Pathologic Aging Scale, There is no significant difference between two groups. We had good internal consistency(Cronbach's alpha = 0.6) and test-retest reliability(r=0.631) but low inter-rater reliability(r=0.430). On Korean Medical Pattern Identification for Dementia, dementia patients diagnosed with Qi deficiency are significantly more than those in normal group. We had fairly good internal consistency(Cronbach's alpha = 0.574) and excellent test-retest(kappa= .800) and inter-rater reliability(kappa = .733). Conclusions: Korean Medical Pattern Identification for Dementia is appropriate for diagnosing korean medical pattern. But Korean Medical Pathologic Aging Scale isn't appropriate to discriminate dementia from normal elderly because of many subjective items. Therefore objective measurement of sensory dysfunction would be needed to measure pathologic aging based on korean medical theory.

• Journal of the Society of Naval Architects of Korea
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• v.32 no.3
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• pp.1-18
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• 1995

This paper deals with the vibration absorbers of gravitational and centrifugal pendulum types for vibration controls of ship's substructures such as radarmasts, bridgewings and funnels. The mathematical model of such a vibrating system with an absorber is described as a 2 degree of freedom system and an efficient formulation for optimum design of the absorber is presented. For investigation applicability of the two types of the absorbers to a structure system, numerical calculations and experiments hove been performed with variation of mass ratios for each type. According to the results of investigations, the vibration absorber of gravitational type proved to be more useful and efficient than one of centrifugal pendulum type in a view point of mass ratio.

• Korean Journal of Community Nutrition
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• v.9 no.5
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• pp.606-614
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• 2004

This study was conducted to investigate the attitude to various soy foods and to estimate dietary isoflavone intake among Korean adolescents. The survey was carried out by self-administered questionnaire with 800 middle and high school students residing in urban and rural areas and 714 questionnaires were collected: resulting in 89% response rate. The dietary isoflavone intake was estimated by food frequency questionnaire developed for rapid assessment of isoflavone intake. Soybean paste, soybean curd, soy milk, bean sprouts and dambuk were recognized as nutritious and healthy food in order. Dambuk got the lowest score in taste and flavor. Bean sprouts, soybean curd and soybean paste were recognized as familiar food in order. Stuffed rice in fried soybean curd got the highest score and Miso soup got the lowest in preference. More than 50% of the subjects consumed soybean paste stew/soup and soybean curd over twice per week and 12.3% of the subjects consumed soybean over once a day. The estimated daily intake of isoflavones ranged from 0 to 227 mg, and the mean daily isoflavone intake of the subjects was 28.1 mg (16.3 mg genistein and 12.0 mg daidzein) whereas the median value of isoflavone intake was 19.7 mg. There was statistically significant relationship among Kyung Gi Do, Chung cheung Do and Seoul residents in their intake of isoflavone. The highest monthly income group consumed isoflavone more than the other groups. These results suggest that Korean adolescent perceived the soybean dishes as high quality foods but they didn't take much because of difficulty to cook or less chance to eat. Nutrition education program is needed to enhance consuming soy foods for prevention of chronic diseases related to dietary isoflavone intake. More detailed information on easy cook method of soy food is also needed.

• Korean Journal of Health Education and Promotion
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• v.15 no.1
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• pp.1-30
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• 1998

A study on skin care was conducted in order to develop proper skin care program and disseminate the Information to the consumers. The study was performed from October 2, 1997 though April 30 1997 by using questionnaires. The subjects were 1,793 from lug cities of Seoul, Pusan and, and 800 from medium and small cities of Kyongsan, Kimchon, Mokpo and KimHae cities. All subjects were females over 20 years. 1. 64.3% of the subjects said that they chose the massage packs after considering their skin condition. 55.1% of the subjects said that they did not know the side effects of the massage packs. 2. 53.3% of the subjects reported that they knew the cause of acne. and 73.3% of the respondents reported that they knew the nature of their body classified by oriental medicine. 3. The average knowledge and attitude was 10.61 :t3.46%( who it is converted to percent, it is 53.1%). The upper limit was 18.9% and lower limit was 19.0%. 4. The factors which are under the influence on knowledge of skin care were the times of massage, education level, the height of subjects, disease of skin, age, the degree of fatty body, the hour of make-up(R2=0.137). 5. The factors which are under the influence on the times of massage were education level, the experience of skin side effect, the status of physic8I health and the birth place of the subjects(R2=0.139). 6. The main factors which had significant effect on the status of face skin health were the status of physical health, economic status, age, the side effect of skin cosmetic, and the hour of make-up(R2=0.140). 7. Finally, it is recommended that training package on side effect of cosmetics, massage, physical characteristics and proper way of make-ups, and the public should be educated on the above mentioned areas.

• KSBB Journal
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• v.9 no.3
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• pp.299-305
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• 1994

Taxol contents in various parts of 15 years old yew tree were determined. The descending order of taxol content per unit mass was stem bark, root bark, needle and seed. In the seed, that order was seed coat, embryo and endosperm. The total amount of taxol extractable from a 15 years old yew tree was 1.68 gram. This amount was distributed in needle, stem bark, root bark and seeds as 48.0, 23.8, 27.9 and 0.4%, respectively. Altitudinal variation of taxol content was also observed. More taxol was observed in yew trees grown at high altitude over 1000m above sea level. Calli and suspension cultures were induced from various yew trees. The presence of taxo] in cultured cells was established bv HPLC. The taxol content in cultured cells were different according to the source of explants. These results may be useful for the goal of large scale taxol production by cultured yew tree cells.