• 제목/요약/키워드: Qualitative Characteristic

검색결과 215건 처리시간 0.027초

가상환경의 시뮬레이션을 위한 충돌반응 양상의 논리적 모델링 (A Logical Model of Collision Response for Simulation of the Virtual Environment)

  • 김병주;박종희
    • 정보처리학회논문지B
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    • 제11B권7호
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    • pp.821-830
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    • 2004
  • 본 논문에서는 지표면을 향해 낙하하는 자유 물체의 충돌 현상에 대해 모델링하고자 한다. 이를 위해 최소한의 근원적인 요소를 찾아서 최대한의 다양성을 제공하고자 한다. 몰입감있는 가상환경 구축을 위해 보다 사실적이고 논리적으로 동작하는 충돌 현상을 표현하는데 설계의 초점을 둔다. 이를 위해, 낙하 물체의 재료(material)적 특성에 대한 범위(domain)를 결정하고 우성력(dominant forte)을 선택할 것이며, 힘과 지표면에 대한 모델링을 구축할 것이다. 이는 충돌 후 발생하는 결과들을 정량적인 면뿐만 아니라 정성적인 면에서도 충족시킬 수 있다. 아울러 기존에 많은 연구가 진행된 충돌 검출 보다는 충돌 반응 양상에 모델링의 초점을 둘 것이다.

Wood anatomy of Korean Symplocos Jacq. (Symplocaceae)

  • GHIMIRE, Balkrishna;PARK, Beom Kyun;OH, Seung-Hwan;LEE, Jaedong;SON, Dong Chan
    • 식물분류학회지
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    • 제50권3호
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    • pp.333-342
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    • 2020
  • Despite poorly documented species delimitation and unresolved taxonomic nomenclature, four species of Symplocos (S. coreana, S purnifolia, S sawafutagi, and S. tanakana) have been described in Korea. In this study, we carried a comparative wood anatomy analysis of all four species of Korean Symplocos to understand the wood anatomical variations among them. The results of this study indicated that Korean Symplocos are comparatively indistinguishable in terms of their qualitative wood features, except for exclusively uniseriate rays present in S. purnifolia instead of uniseriate to multiseriate in other three species. Nevertheless, differences are noticed in quantitative wood variables such as the vessel density, vessel size, and ray density. The vessel density of S. purnifolia is more than twice as high as those of S. sawafutagi and S. tanakana. In contrast, the vessel circumference and diameter on both plants of S. sawafutagi and S. tanakana is nearly twice as large as those of S. purnifolia. Symplocos coreana has characteristic intermediacy between these two groups in terms of vessel features and is closer to S. purnifolia in terms of its ray density level. A cluster analysis based on a paired group (unweighted pair-group method with the arithmetic mean, UPGMA) algorithm using the Euclidean similarity index clearly differentiates S. purnifolia from the remaining species, representing the first branch of the phenogram.

퍼지근사추론에 의한 폐터널의 보강방식 선정 (Determination of Reinforcement Method for Abandoned Tunnel by Fuzzy Approximate Reasoning)

  • 조만섭
    • 터널과지하공간
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    • 제14권4호
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    • pp.275-286
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    • 2004
  • 본 논문에서는 신규 터널노선과 교차하는 폐터널의 보강방식을 결정하기 위하여 의사결정기법을 검토하였고, 여러 가지 의사결정기법들 중에서 설문조사의 과정을 최소화 하고, 조사항목 별 정성적ㆍ정량적 특성을 모두 반영할 수 있도록 쌍대비교와 퍼지근사추론을 이용하여 폐터널의 보강방식에 대한 적정성을 평가하여 보았다. 페터널 보강방식을 선정하기 위하여 4개의 주 요인들 즉, 시공성, 경제성, 안전성, 유지관리성을 평가의 수단으로 사용하였고, 간단한 설문조사와 쌍대비교행렬을 이용하여 4가지 주 요인들의 가중치를 결정하였다. 퍼지근사추론은 4개의 주 요인별 평가점수를 산정 하는데 사용되어졌고, 이 결과들에 가중치를 반영하여 최종적인 폐터널의 보강방식을 선정할 수 있었다.

Variation of the Essential oil and Main Component from Different Origin of Levisticulum officinale Koch

  • Chung, Hae-Gon;Kim, Seong-Min;Nemeth, E.
    • 한국약용작물학회지
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    • 제10권4호
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    • pp.298-302
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    • 2002
  • The essential oils were isolated by hydrodistillation and their composition determined capillary GC method with standards. The essential oil content showed significant differences between the two populations on the vegetative organs. The essential oil level of the leaves and roots was considerably higher in the Korean population at full flowering and waxy ripening stage but essential oil content of the roots was significantly higher in the Hungarian taxon at leaf rosette stage. We observed the essential oil accumulation tendency was mianly dependent on plant organs and intra-specific taxon during the vegeation period. Butylidene-phthalide was proved to be the main component of the oil in both population roots (50.9-73.3%), while dimethyl-acetate was showed as a major compound on the over-ground parts (56.7-62.0%). The qualitative composition of the essential oil in the reproductive organs concerning the identified compounds was the same as the vegetative parts with the main component ${\alpha}-phellandrene$ (4.8-28.1%) and butylidene-phtalide (9.7-16.1%), The quantitative composition showed some changes during the ontogenesis phases. Most characteristic ones are the decreasing proportion of dimethyl-acetate (from 7.3% to 1.1%) and the appearance of ${\alpha}-pinene$ (from 0.5% to 1.5%) only after fruit setting in both population.

절삭력과 음향방출 신호를 이용한 밀링공구의 파손 검출 (Fracture Detection of Milling Cutter Using Cutting Force and Acoustic Emission Signals)

  • 맹민재
    • 한국기계가공학회지
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    • 제3권1호
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    • pp.28-37
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    • 2004
  • An on-line monitoring system of endmill failure such as weal, chipping, and fracture is developed using AE, cutting force Characteristic variations of AE and cutting force signals due to endmill failure are identified as follows. When endmill fracture occurs, AE count rate shows a rapid Increase in conjunction with a subsequent decrease while a standard deviation of the principal cutting force Increases significantly. The increase of AE count rate precedes the Increase of standard deviation of principal cutting force. Chipping results in relatively small increase and decrease of AE count rate without any significant variation of the cutting force Gradual increase of AE count rate and mean principal cutting force are Identified to be related with the wear of cutter. A cutter fracture detection algorithm is developed based on the present results. The signals me normalized to enhance the applicability of the algorithm to Wide those of fresh cutters, and qualitative characteristics of AE signals encountered at the moment of fracture are employed. It is demonstrated that the algorithm can detect the cutter fracture successfully.

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문헌정보학 연구방법으로서의 이야기 - 내러티브 탐구를 중심으로 - (Narrative Inquiry, As a Research Methodology for Library and Information Science)

  • 이호신
    • 한국문헌정보학회지
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    • 제49권1호
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    • pp.149-172
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    • 2015
  • 이 연구는 문헌정보학 연구방법의 하나로 이야기의 가능성을 제안하기 위한 것이다. 이를 위해서 먼저 사회과학적인 인식의 방법으로서 이야기의 가능성과 힘을 논의하고, 서구 사회과학의 해석학적인, 내러티브적인 전환에 대하여 살펴보았다. 아울러 연구의 대상이면서 방법인 내러티브 탐구의 특징과 수행 절차를 소개하고, 문화기술적 연구와 현상학적 연구 등과 비교하여 제시하였다. 또한 미국에서의 선행연구 사례를 소개하면서 문헌정보학 분야에서의 내러티브 탐구의 적용 가능성을 살펴보았다.

정적연소기에서 토치의 체적 변화에 따른 메탄의 연소특성 파악 (A Study on Combustion Characteristic Methane Fuel according to Torch Volume Variation in a Constant Volume Combustion Chamber)

  • 권순태;박찬준;엄인용
    • 한국가시화정보학회지
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    • 제9권1호
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    • pp.42-48
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    • 2011
  • Six different size of torch-ignition device were applied in a constant volume combustion chamber for evaluating the effects of torch-ignition on combustion. The torch-ignition device was designed for six different volumes and same orifice size. The combustion pressures were measured to calculate the mass burn fraction and combustion enhancement rate. In addition, the flame propagations were visualized by shadowgraph method for the qualitative comparison. The result showed that the combustion pressure and mass burn fraction were increased when using the torch ignition device. And the combustion duration were decreased. The combustion enhancement rates of torch-ignition cases were improved in comparison with conventional spark ignition. Finally, the visualization results showed that the torch-ignition induced faster burn than conventional spark ignition due to the earlier transition to turbulent flame and larger flame surface, during the initial stage. Finally, the initial flame propagation was affected by torch-ignition volume.

대한민국 건강도시 평가(2008-2010) (Evaluation of the Healthy Cities in Korea(2008-2010))

  • 오유미;김혜정;홍경수
    • 보건교육건강증진학회지
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    • 제28권3호
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    • pp.99-111
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    • 2011
  • Objectives: This study aims at evaluating performance of the Healthy Cities in Korea during the period of 2008-2010. Furthermore, it will explore future direction for qualitative growth of the Healthy Cities in Korea. Methods: A survey has been conducted annually with current healthy cities; 46 in 2009, 56 in 2010 and 60 in 2011. Survey instrument consists of 13 questions to evaluate general status, implementation system and sub-programs, and the result of the survey was analyzed by using PASW Statistic 18.0 focusing on categorizing healthy cities and looking at sub-programs trends. Results: In 2010, there are 60 Healthy Cities in Korea, whose number grows continuously. The most noticeable characteristic is that administrative bodies in urban area strongly promote the Healthy Cities Project, while the projects are usually associated with other health promotion projects rather than independently carried out. Also, their sub-programs are concentrated on 'healthy-setting' and 'healthy lifestyle programs'. Conclusions: To improve the quality of the Healthy Cities in Korea, a number of requirements should be met. The most urgent requirement is sector-wide comprehensive policy fostering Healthy Cities development strategy. Moreover, it is expected that over-arching theme should be set up under the framework of National Healthy Cities Network.

배합수에 따른 안정액의 공학적 특성 분석 (A Study on Engineering Characteristics of the Drilling Fluid Dependingon the Mix Water)

  • 최정혁;유충식;한윤수
    • 한국지반신소재학회논문집
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    • 제15권4호
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    • pp.43-52
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    • 2016
  • 본 논문에서는 지반 시추 시 공벽붕괴 방지를 위해 사용되는 안정액의 다양한 배합비에 따른 공학적 특성에 대한 실험적 연구를 다루었다. 이를 위해 먼저 배합수가 청수일 경우, 안정액의 공학적 특성을 검토하였으며 아울러 해수 배합시 안정액의 공학적 성능 변화에 대한 공학적 특성을 분석하였다. 그 결과, 청수에서 벤토나이트와 폴리머를 추가할 경우 공학적 성능이 향상되는 것으로 나타났으며, CMC에 비해 Polymer의 증점 효과가 우수한 것으로 검토되다. 또한 해수의 경우 벤토나이트에 비해 내염성점토의 내염성 성능이 우수한 것으로 검토되었다. 따라서 본 논문에서는 시공시 배합수에 따른 안정액을 성능에 대한 정성적인 결과를 제시하였다.

소집단 탐구기법을 활용한 '계절의 변화 원인' 학습이 공간지각 개념 및 창의적 인성에 미치는 효과 (The Effects of the Space Perception Ability and Creative Personality 'Source of Season Change' Using Small Inquiry Method)

  • 이용섭
    • 대한지구과학교육학회지
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    • 제5권3호
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    • pp.307-315
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    • 2012
  • The purpose of this study was to examine the effects of small inquiry method on space perception ability and creative personality. Testees of this research are 36 elementary pre-service teachers taking an astronomical observation class. Doing inquiry activity after 36 elementary pre-service teachers are classified into 6 Jigsaw small inquiry. Learning activity was split into two groups, expert group and a population. To find out research outcome, pre-test was executed space perception ability test, creative personality test. Analysis of test result was accomplished with statistical package SPSS 18.0 paired t testing hypothesis. The results of this study are as follows. First, 'source of season change' class using Jigsaw small inquiry method has effect on space perception ability improvement. This was interpreted that space perception ability improvement was effective because characteristic of Jigsaw small inquiry is made up of lots of semin Second, 'source of season change' class using Jigsaw small inquiry method has no effect on creative personality. This was interpreted that experiment and discussion activity getting accomplished in a short time has no effect on qualitative characterizing Creative Personality improvement.