• 제목/요약/키워드: Authors determined

검색결과 320건 처리시간 0.035초

축대칭 압출 공정에서 상계법을 이용한 금형 접족면압의 계산 (Calculation of Contact Pressure to the Die of Axisymmetric Extrusion by Using Upper Bound Solution)

  • 최영;여홍태;허관도
    • 한국정밀공학회지
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    • 제21권12호
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    • pp.133-139
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    • 2004
  • In general, the contact pressure to the die cannot be easily determined by using upper bound solution. Recently, the authors have proposed the method determining the contact pressure with the upper bound solution for the forming with the plane stain plastic deformation. In this paper, the method is applied to an axisymmetric forward extrusion process. The contact pressure to the die of the axisymmetric extrusion has been determined with the upper bound solution and compared with the result of rigid plastic FEM. The optimal semi-angles of die have been obtained minimizing the relative contact pressure to die fur the extrusion ratio.

매립석탄회 고배합 콘크리트 배합설계 기법 (Concrete Mixture Design Method with Large Amount of Land Reclamation Ash)

  • 한상묵;송영철;하재담
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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    • pp.344-347
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    • 2004
  • The amount of coal ash has been increasing and development of effective use is urgently needed. Various by-products and waste are expected to be used as resources from the point of reduction in environmental load. This is an experimental study to compare the properties of high volume coal ash concrete using the reclaimed coal ash. For this purpose, authors have started work to develop a production method of hardening coal ash concrete. Laboratory tests show that the optimum mixture of coal ash concrete can be determined from multiple regression analysis. According to test results, it was found that the compressive strength of the concrete can be determined by a single curve. And it is obtained from the analysis of the results tested for concrete with the ratio of total power to water and amount of land reclamation ash.

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장수명주택 해외진출을 위한 대상국가의 외부환경분석 (External Environment Analysis of Target Countries for Overseas Expansion of Long-life Housing)

  • 정준수;이보라
    • 한국주거학회논문집
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    • 제26권5호
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    • pp.71-78
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    • 2015
  • Currently, the Korean construction industry is shifting its interest to the overseas construction market because of a stagnating domestic market. In the meantime, the international housing construction market is expanding with respect to new city development projects that are supported by population growth and urban migration. Despite the Korean construction industry's expertise in new city development, technology, and systems for apartment supply, the share of Korean players in the international housing construction market is continuously decreasing. As a measure to overcome this situation, the authors of this study considered the paper "The Development of a Cost Effective, Long-life Housing Model and Construction of Testbed," which is currently in progress as a part of national project. Through literature review and interviews with experts, the authors determined that there are "column+minimum interior (infill)" apartments that are similar to the long-life housing in some areas of China, Southeast Asia, and Russia. Candidate countries expected to be feasible for the entry of long-life housing were selected by determining the top countries that have already entered the long-life housing market and analyzing those selections through additional specific techniques. The external environments of the selected countries were also analyzed. Please refer to the full paper for details.

악교정수술 및 교정치료를 위한 개별화된 이상적인 교합평면에 관한 연구 (INDIVIDUALIZED IDEAL OCCLUSAL PLANE FOR ORTHOGNATHIC SURGERY AND ORTHODONTIC TREATMENT (PRELIMINARY STUDY))

  • 황윤정;양상덕;최진영
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제31권2호
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    • pp.143-148
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    • 2009
  • Introduction: To correct abnormal occlusal plane by orthognathic surgery, we need to have clear criteria for therapeutic occlusal plane. Authors introduced the concept of individualized ideal occlusal plane(Y-plane), which is determined by the size and form of the mandible, and the ideal incisor tip considering upper and lower lip. Authors studied the following to verify if the actual occlusal plane of the patients with optimal jaw relationship corresponds with the individualized ideal occlusal plane. Patients: We reviewed 44 patients who have normal occlusion visitied in the Dept. of orthodontics, Pundang CHA hospital. Methods: We evaluated if there are agreement between individualized ideal occlusal plane(Y plane) and occlusal plane of actual patients. And we confirmed if tested group has a normal face by measuring FABA, FMA, AB-LOP. Results: There were no significant differences of FABA, FMA, AB-LOP, Mo-Y plane between male and female. FABA, FMA and AB-LOP were included in the normal value. Average distance of Mo-Y plane was $0.75{\pm}0.78mm$. Conclusion: Individualized ideal occlusal plane may be applied to orthognathic surgery.

MCS-BEq 알고리즘에 의한 $SF_6-Ar$ 혼합기체의 확산계수 (Diffusion Coefficients in $SF_6-Ar$ Gas used by MCS-BE Algorithm)

  • 김상남
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2006년도 춘계학술대회 논문집
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    • pp.298-301
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    • 2006
  • This paper describes the electron energy distribution function characteristics in $SF_6-Ar$ gas calculated for range of E/N values from $50\sim700[Td]$ by the Monte Carlo simulation(MCS) and Boltzmann equation(BE) method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters are obtained by time of flight(TOF) method. In this dissertation the results of the combined experimental and theoretical studies designed to understand and predict the spatial growth and transport coefficients for electrons in $SF_6$ and $SF_6-Ar$ mixtures have described. The ionization and attachment coefficients in pure $SF_6$ and $SF_6-Ar$ mixtures have been calculated over the range of 10$SF_6$ molecule and for Ar atom proposed by other authors. The results obtained in this work will provide valuable information on the fundamental behaviors of electrons in weakly ionized gases and the role of electron attachment in the choice of better gases and unitary gas dielectrics or electro negative components in dielectric gas mixtures.

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한의학 학술지에서의 이중게재 현황 (The trends of duplicate publication in Korean Medical journals.)

  • 안진향;이영진;곽재영;김민희;최인화
    • 대한한의학회지
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    • 제38권3호
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    • pp.103-110
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    • 2017
  • Objectives: The purpose of this study was to examine trends in duplicate publication in Korean medical articles indexed in the Oriental Medicine Advanced Searching Integrated System(OASIS). Methods: We searched the list of papers published in Korean medical journals by using OASIS. We randomly extracted 10% of total articles (n=1,162). We searched using OASIS by entering keywords from the title and names of the first and last authors of each indexed article. After the librarian selected the candidates of duplicate publication, three authors reviewed the full texts of the articles independently. When their opinions were not in agreement, reconciliation was made by discussion. The patterns of duplicate publication, such as copy, salami slicing (fragmentation), and aggregation (imalas), were also determined. Results: A total of 1162 articles were evaluated, 24 (2.1%) index articles of which were duplicate articles. Among 24 index articles, Two were triple publications and 22 were double publications. The patterns of duplication publication were as follows; (1) copy (n=8, 33.3%); (2) salami (9, 37.5%), (3) imalas (5, 20.8%) (4) others (2, 8.3%). Conclusion: Duplicate publications have appeared in Korean medical journals in a small proportion. Education on publication ethics and authors'ethical awareness is needed.

$SF_6$-Ar 혼합기체(混合氣體)의 전자(電子) 평균(平均)에너지 (Mean energy of electrons in $SF_6$-Ar Mixtures Gas)

  • 김상남;성낙진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 학술대회 논문집 전문대학교육위원
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    • pp.75-78
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    • 2003
  • Energy distribution function for electrons in $SF_6$-Ar mixtures gas used by MCS-BEq algorithm has been analysed over the E/N range $30\sim300$[Td] by a two term Boltzmann equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6$-Ar mixtures were measured by time-of-flight(TOF) method. The results show that the deduced electron drift velocities, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients and mean energy agree reasonably well with theoretical for a rang of E/N values. The transport coefficients for electrons in (0.2[%])$SF_6$-Ar and (0.5[%]$SF_6$ - Ar mixtures were measured by time-of-flight method, and the electron energy distribution function and the parameters of the velocity and the diffusion were determined by the variation of the collision cross-sections with energy. The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

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$SF_6-Ar$ 혼합기체(混合氣體)의 MCS-BEq알고리즘에 의한 전자(電子) 평균(平均)에너지 해석(解析) (Analysis on the Mean energy of electrons in $SF_6-Ar$ Mixtures Gas used by MCS-BEq Algorithm)

  • 김상남;하성철
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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    • pp.281-284
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    • 2004
  • Mean energy of electrons in $SF_6-Ar$ Mixtures Gas used by MCS-BEq algorithm has been analysed over the E/N range $30{\sim}300[Td]$ by a two term Boltzmann equation and by a Monte Carlo Simulation using a set of electron cross sections determined by other authors, experimentally the electron swarm parameters for 0.2[%] and 0.5[%] $SF_6-Ar$, 0.1[%] and 5.0[%], $SF_6-Ar$ mixtures were measured by time-of-flight(TOF) method. The transport Coefficients for electrons in (100[%])$SF_6$. (100[%])Ar, (0.2[%])$SF_6-Ar$ and (0.5[%]) $SF_6-Ar$, (5.0[%]) $SF_6-Ar$, (0.1[%])$SF_6-Ar$ mixtures were measured by time-of-flight method, and the electron energy distribution function and the parameters of the velocity and the diffusion were determined by the variation of the collision cross-sections with energy. The results obtained from Boltzmann equation method and Monte Carlo simulation have been compared with present and previously obtained data and respective set of electron collision cross sections of the molecules.

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프런트 필라 트림의 내열특성 향상을 위한 순차적 실험계획법과 인공신경망 기반의 최적설계 (Optimum Design based on Sequential Design of Experiments and Artificial Neural Network for Heat Resistant Characteristics Enhancement in Front Pillar Trim)

  • 이정환;서명원
    • 한국정밀공학회지
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    • 제30권10호
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    • pp.1079-1086
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    • 2013
  • Optimal mount position of a front pillar trim considering heat resistant characteristics can be determined by two methods. One is conventional approximate optimization method which uses the statistical design of experiments (DOE) and response surface method (RSM). Generally, approximated optimum results are obtained through the iterative process by a trial and error. The quality of results depends seriously on the factors and levels assigned by a designer. The other is a methodology derived from previous work by the authors, which is called sequential design of experiments (SDOE), to reduce a trial and error procedure and to find an appropriate condition for using artificial neural network (ANN) systematically. An appropriate condition is determined from the iterative process based on the analysis of means. With this new technique and ANN, it is possible to find an optimum design accurately and efficiently.