• 한국자동차공학회논문집
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• 제13권2호
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• pp.142-148
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• 2005

In this paper, the stress singularity on interface of friction welded dissimilar materials was investigated by using 2-dimensional elastic boundary element method. It is required that stress distributions and stress singularities on an interface for friction welded dissimilar materials analize to establish strength evaluation. The stress singularity index ($\lambda$) and stress singularity factor ($\Gamma$) were calculated from the results of stress analysis. The stress singularities on variations for shapes and thickness of friction welded flashes were analized and discussed. This paper suggested that the strength evalution by using the stress singularity factors as fracture parameters, considering the stress singularity on an interface edge of friction welded dissimilar materials were very useful.

• Journal of Biosystems Engineering
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• 제22권2호
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• pp.227-236
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• 1997

Manual grading and sorting of red-ginsengs are inherently unreliable due to its subjective nature. A computerized technique based on optical and geometrical characteristics was studied for the objective quality evalution. Spectral reflectance of three categories of red-ginsengs - "Chunsam", "Chisam", "Yangsam" - were measured and analyzed. Variation of reflectance among parts of a single ginseng was more significant than variation among the quality categories of ginsengs. A PC-based image processing algorithm was developed to extract geometrical features such as length and thickness of body, length and number of roots, position of head and branch point, etc. The algorithm consisted of image segmentation, calculation of Euclidean distance, skeletonization and feature extraction. Performance of the algorithm was evaluated using sample ginseng images and found to be mostly sussessful.

• 분석과학
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• 제5권2호
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• pp.217-222
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• 1992

수은침투법을 이용하여 AIN의 이장성형체와 건조가압성형체의 기공구조 해석을 시도하였다. 좁은 기공크기 분포와 높은 충진밀도를 가진 이장성형체에서 소결도가 높고 2차상의 분포가 균일하였다. 수은침투법에 의한 기공크기 분포 해석은 잉크병 현상이 없을 때만 유효하지만 정량미시 분석과의 비교결과 기공률의 측정은 개기공 상태이면 유효함을 보였다.

• 한국광학회지
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• 제9권6호
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• pp.396-402
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• 1998

광학계의 결상성능평가는 optical transfer function(OTF)을 측정하는 것이 표준적인 방법으로 사용되고 있다. 그러나, 대량 생산되는 광학계의 경우에서는 측정의 편리함 때문에 test pattern을 투영하여 contrast를 검사하는 방법도 많이 사용되고 있다. 본 연구에서는 회절결상이론을 사용하여 주기적 line-space pattern에 대한 contrast transfer function(CTF)을 계산하는 프로그램을 개발하고, C­계수와 Zernike 다항식으로 표현되는 3차 파면수차에 의한 광학계의 modulation transfer function (MTF)과 CTF 변화를 비교, 분석하였다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2000년도 The 7th International Symposium
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• pp.52-63
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• 2000

Many plant species are used in China in traditional medicine for the prevention and treatment of cancer. This paper presents some of these species with details on other pharmacologic evaluation and its traditional Chinese meditional uses. The known bioaktivities and some chemical constituents of each of the species given. Information on bioactivities of each species resulting from tests on experimental animals are given. Many of the known chemical constituents of each species are given. Various species of plants elective for various types. In this meeting I will present on some antitumor of the plants which are as follows; (1) Akebia trifoliata(Thunb.)Koidz. ((2) Panax notoginseng(Burk.) F, H, Chen., (3) Ziziphus jujuba Mill., (4) coriolus versicolor(Fr.)Que l., (5) Trichosanthes kirilowii Maxim., (6) Ficus carica Linnaeus., (7) Acanthopanax senticosus(Rupr.et Maxim.)Harms., (8) Hibiscus mutabilis Linnaeus., (9) Arctium lappa Linnaeus., (11) Agrimonia pilosa Ledebour and (12) Hedyotis diffusa Willd.

• 한국생활과학회지
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• 제7권2호
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• pp.161-169
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• 1998

The purpose of this study is to find some major factors which can be used as basic design guideline for the elderly housing as the comfortable dwelling circumstances to keep life as self-reliant and secure as possible in their life. The subjects for this study were 200 elderly women in Taegu, data were collected through an individual visiting interview from 29th, Oct. to 15th, Nov., 1997. The major findings are as follows: 1) The elderly women preferred to live 30.3 pyung as the house size, and they desire to live with the married son's family in urban areas. 2) The evalution for the dwelling circumstance was unsatisfatory on the whole. All the preferred housing characteristics were different from the current housing characteristics. The comfortability of dwelling was least satisfied while the space size was most satisfied.

• 대한가정학회지
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• 제31권4호
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• pp.37-51
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• 1993

The Objects of this study are: 1. To compare the housework time of housewives by region and employment status. 2. To compare the economic value of housework by region and employment status. 3. To evaluate the economic value of housework by each method. The subjects of this study were 815 housewives living in Taegu and Kyungsangpookdo. The statistics used for data analysis were frequency, percentile, T-test, ANOVA and Seheffe test by SPSS PC programs: 1) The average housework time was 7.8hours per day. Full-time housewives spent 8.2hours and employed housewives spent 6.7hours to housework. 2) Partially there were significant difference in economic value of housework by employment status. 3) Estimates of economic value of housework by each method of evaluation are : (unit : won) sample mean method monthly (1) Specialized substitute method 587,080 (2) Overall substitute method 760,640 (3) Opportunity cost method 556,060 (4) Reservation wage method 534,070 (5) Subjective evalution method 644,540

• Journal of Pharmaceutical Investigation
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• 제25권4호
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• pp.347-351
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• 1995

Antisense phosphorothioate oligodeoxynucleotide(PS-ODN) against $TGF-{\beta}$ was developed as scar formation inhibitor. The scar was caused collagen deposition due to overexpression of $TGF-{\beta}$ in wounded skin. The percutaneous absorption of partially modified PS-ODN(25 mer) was investigated for the purpose of its effective delivery. Though PS-ODN has high molecular weight (MW=8,000) and polyanionic charge, it was permeated through skin. The skin permeation of PS-ODN was markedly increased by the removal of stratum corneum and dermis. Moreover, the skin permeation of PS-ODN was decreased in the following order; hairless mouse skin>rat skin>human cadaver skin. Thus, PS-ODN represents a logical candidate for further evalution due to the potential for delivery into the wounded skin.

• 한국정보처리학회논문지
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• 제4권2호
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• pp.483-490
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• 1997

비중심 $X^2$분포의 누적분포 함수의 계산은 $X^2$검정에서 검정력 계산에 요구된다. 비중심 $X^2$분포의 확률계산은 일반적으로 많은 시간이 소요될 뿐 아니라 정확성이 문제가 되어 여러 접근 방법들이 계산속도와 정확성을 고려하여 제시되었다. 따라서 본 논문에서는 기존의 비중심 $X^2$분포의 확률 계산 접근방법에 의한 계산결과를 비교하고 자유도와 비중심모수에 따른 효율적인 접근방법을 탐색하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.201-215
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• 2003

At present, European railways in U.K., Sweden, and Belgium have taken serious efforts to improve railway services by implementing a service evaluation system. Not only do they measure the service-related performance of a railway system, but also operate an incentive system according to the results of service-related performance. This performance evaluation system can be also used to provide basic data for other policies such as fares, subsidies and track user charges etc. After the restructuring process of Korean national railways, therefore, although it is expected to face many difficulties in the future, it is desirable to implement a performance evaluation system for securing the long-term growth of Korean railway industry.