• 제목/요약/키워드: Representative Characteristics

검색결과 2,328건 처리시간 0.028초

Reaction of Dipyrrolidinoaluminum Hydride in Tetrahydrofuran with Selected Organic Compounds Containing Representative Functional Groups

  • Jin Soon Cha;Oh Oun Kwon;Jong Mi Kim;Jae Cheol Lee
    • Bulletin of the Korean Chemical Society
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    • 제15권8호
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    • pp.644-649
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    • 1994
  • The approximate rates and stoichiometry of reaction of excess dipyrrolinoaluminum hydride (DPAH) with selected organic compounds containing representative functional groups under standardized conditions (tetrahydrofuran, 0, reagent : compound=4 : 1) were examined in order to define the characteristics of the reagent for selective reductions. The reducing ability of DPAH was also compared with that of bis(diethylamino)aluminum hydride (BEAH). The reagent appears to be stronger than BEAH, but weaker than the parent reagent in reducing strength. DPAH shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, acid chlorides, epoxides, and nitriles readily. In addition to that, ${\alpha},\;{\beta}$-unsaturated aldehyde is reduced to the saturated alcohol. Quinone are reduced cleanly to the corresponding 1,4-reduction products. The examination for possibility of achieving a partial reduction to aldehydes was also performed. Both primary and tertiary aromatic carboxamides are converted to aldehydes with a limiting amount of DPAH. Finally, disulfides and sulfoxides are readily reduced to thiols and sulfides, respectively.

Characteristics of micro-plastics in stormwater sediment basin: Case study of J wetland

  • Jiyeol Im;Kyungik Gil
    • Membrane and Water Treatment
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    • 제14권4호
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    • pp.147-153
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    • 2023
  • Urbanization has been causing such new pollutants as micro-plastic, thus the environmental impact of new pollutants on ecosystem is rapidly increasing. When it comes to micro-plastic, a representative artificial trace pollutant, its risk has been increased at a much faster rate, however the depth study associated with stormwater sediment and wetland was relatively rare. In this research, soil samples from storm water sediment were analyzed for distribution characteristics of micro-plastics in the J wetland (registered as Ramsar wetland, May 2021 and a representative environmental site in South Korea). Analyzed soil samples found approximately 201 ± 93 particle/kg (based on unit weight, Total micro plastic particles / Total Sample weight) micro-plastics in the samples. When considering the total quantitative numbers in stormwater sediment in the entire area of the J wetland, over 15,000 micro-plastics were estimated to be contaminating such area. In addition, in terms of qualitative numbers, micro-plastics were contaminating the J wetland with 94.7 % ratio of styrofoam type (43.9%) and polyethylene type (50.8%). These research results can be used as base data sets for controlling micro-plastics in the J wetland.

Morphology, Pathogenicity and Molecular analysis of Alternaria Isolates from Solanaceous Crops (oral)

  • Cho, H.S.;Park, M.S.;Kim, B.R.;Yu, S.H.
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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    • pp.112.3-113
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    • 2003
  • More than 30 isolates of Alternaria were obtained from various solanaceous crops in Korea. For all isolates, morphological characteristics of the conidia were determined and compared with those of representative isolates of A. solani and A. tomatophila. Pathogenicity test was performed to Potato, tomato, egg plant and red Pepper and molecular characteristics of them including the representative isolates were determined using sequence analyses of ITS rDNA and histone H3 gene, and URP-PCR analysis. Based on morphological characteristics, the isolates from the solanaceous crops were grouped as identical or very similar to either A. tomatophila(ATO), A. solani(ASO), and unidentified Altemaria sp.(ASP). Among the molecular markers used in this study, the URP-PCR analysis was found to be appropriate for taxonomic resolution of these species. Based on the conidial morphology, pathogenicity test and molecular characteristics, A. tomatophila(early blight of tomato) could be distinguished from A. solani(early blight of potato), and the Alternaria sp.(ASP) from potato, which was closely related to A. solani in conidial morphology, was considered as a new species.

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국내 보조기층 재료의 변형특성을 고려한 전체 변형률 영역의 구성모델 개발 (Development of whole Strain Range Constitutive Model Considering Deformational Characteristics of Subbase Materials in Korea)

  • 권기철
    • 한국도로학회논문집
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    • 제6권3호
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    • pp.65-77
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    • 2004
  • 보조기층 재료의 변형특성은 역학적 포장설계에 있어서 대단히 중요한 입력변수이다 국내에서 사용되는 보조기층 재료는 대부분 입상의 자갈질 흙으로서, 실제 시공현장에서 7종의 시료를 채취하였다. 보조기층 재료의 변형특성 평가를 위하여 공진주/비틂전단시험 삼축압축시험,자유단공진주시험을수행하여 탄성계수에 대한 여러 영향요소를 검토하였다. 보조기층 재료의 탄성계수에 대한 하중주파수 및 하중반복횟수의 영향은 매우 작은 것으로 평가되었으며 공학적 관점에서 무시가능 할 것으로 생각된다 보조기층 재료의 탄성계수는 구속응력과 변형률 크기에 대단히 큰 영향을 받는 것으로 나타났고, 대표적인 정규화탄성계수 감소곡선과 구성모델을 제안하였다.

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르네상스 시기의 유토피아 문학에 나타난 도시.건축에 관한 연구 (A Study on the Urban & Architecture that were Described in Utopian Literature of Renaissance Period)

  • 이일형
    • 건축역사연구
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    • 제19권6호
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    • pp.79-98
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    • 2010
  • If we take account of the 'Architectural Tradition' which aims a construction of better environment, we can see that this tradition has ended historically toward Utopia. And the concrete concepts of utopia mainly started on the Renaissance periods. The Utopias were described well in the literatures which contained particularly three representative utopian books in Renaissance period. The one was the most famous novel by Sir Thomas More and the other were by Tommaso Campanella and by Francis Bacon. These novels expressed ideal commonwealths in which inhabitants exist under perfect conditions, ideally perfect places or state of things. The plans of utopia are complete projects of image, its goal is an political, social and economical improvement according to the eras. Their utopias mostly had characteristics as follows; their shape of islands were almost circle, their shape of cities were rectangularity or circle and attached importance to geometrical compositions, their structure of cities were self-sufficiency in closed spaces and their architectural characteristics were uniformity, simplicity and non-ornament. And these architectural characteristics are urban and architectural traditions in communist countries. Also their utopian novels had not much explanations to daily lives of people like as birth, death, relative, mental conflict or authority, money, art. So their utopian novels were not practical and had inappropriate aspects.

색상영역과 비색상영역의 히스토그램을 이용한디지털 영상의 대표색상 추출 (Extraction of Representative Color of Digital Images Using Histogram of Hue Area and Non-Hue Area)

  • 곽내정;황재호
    • 대한전자공학회논문지SP
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    • 제47권2호
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    • pp.1-10
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    • 2010
  • 디지털 콘텐츠의 응용분야가 확산되면서 디지털 콘텐츠의 색상을 표준화하기 위한 연구가 활발히 진행되고 있다. 따라서 색상을 이용한 영상의 특징을 표현하는 방법도 표준화에 준한 연구가 필요하다. 또한 다양한 응용분야에 사용될 수 있는 색상 특징을 추출하는 방법도 필요하다. 본 논문에서는 디지털 표색계의 근간이 되는 먼셀좌표계를 기본으로 하여 기준색상을 50색상으로 정의하고 영상 내 색상의 분포 특성을 알 수 있는 히스토그램을 구하고 영상을 대표할 수 있는 대표색상을 추출한다. 제안 방법의 성능을 평가하기 위해 18개의 실험영상을 만들어 기존의 방법과 제안방법을 적용하였으며 일반영상에도 적용하여 그 결과를 분석하였다. 제안방법을 적용한 결과영상은 영상 내에 존재하는 색상의 분포 특성을 잘 나타내주며 대표색상으로 빈도가 집중함으로 영상의 대표색상을 이용하여 다양한 응용분야에 적용이 가능하다.

활동기반 접근법에 의한 활동패턴의 맥락적 정보분석과 프로파일 (An Activity-Based Analysis of Contextual Information of Activity Patterns and Profiles)

  • 조창현
    • 대한교통학회지
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    • 제25권6호
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    • pp.171-183
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    • 2007
  • 도시교통 수요는 활동 수행으로부터 유발된다. 개인의 활동 의사결정에 의한 일상활동의 개인 간 총합은 집합적 공간행동으로 관찰되며, 활동간 서로 다른 공간의 극복을 위해 유발된 통행은 활동 간의 구조적인 상호연쇄관계에 의해 그 구체적 형태를 부여받는다. 개인의 하루 일상을 통한 시공간적 의사결정 및 사회적 실행과 사회 공간적 환경간의 상호작용을 탐구하는 활동기반접근법은 도시민의 일상과 통행을 분석하는데 중요한 이론 틀을 제공한다. 이 연구는 도시민의 일상활동을 활동기반접근법에 근거하여 대표적인 유형으로 분류하고, 분류된 유형의 프로파일과 관련 있는 활동 주체 특성과 활동 당시의 상황 특성을 분석하였다. 분석 결과 도시민의 일상활동은 소수의 대표적 활동패턴 집단으로 분류 가능하며, 각 집단의 특성은 다차원 프로파일에 의해 유의하게 요약되었다. 또한 각각의 프로파일은 서로 다른 사회경제적, 상황적 특성과 상관되어 있음을 확인하였다. 연구는 도시민의 일상활동 원리를 밝힘으로써, 도시교통 정책수단에 대한 도시민의 개별 반응 양식과 그 집합적 행동을 예측하기 위한 이론적 기초를 제공한다.

주거공간 내 가족유형별 사용행태에 따른 실내공간계획에 관한 연구 (A Study on a design for an interior space accompanied by an using pattern in behaving As a family types in housing space)

  • 이병영;최경란
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2003년도 춘계학술발표대회 논문집
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    • pp.117-122
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    • 2003
  • This study deals with apartments, the representative form of residence in Korea, and analyzes the residential plane of 30-pyong apartments that are constructed by the 5 construction companies within in the past three years. It is discovered that these apartments show a certain form and that developing the frame work of interior elements according to the characteristics of family types of 30-pyong apartment residents and the process for such a frame work are needed. Therefore, by analyzing the differences of residential forms according to resident types, this investigation tries to approach the design centering around users. To summarize the steps and contents of this study, first, it draws the understanding and the study field of common residential space, second, it shows the characteristics of family types within residential space, third, it analyzes and verifies the differences of characteristics according to family types within the representative size and form of plane. This investigation is aimed to provide the reasons for developing different planes according to family types despite they may be of the same size, to show the frame of the study method for developing the plane design and the interior element design for users and to suggest the way of designing residence in a conditional approach applying the conditions of users within common residential space.

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충주 지역농산물을 활용한 메뉴 개발을 위한 관능적 특성 및 소비자 기호도 조사 (A Study on the Sensory Characteristics and Consumer Preferences for the Development of Food Menus Using Agricultural Products in Chungju)

  • 양정은;이호진
    • 한국식품영양학회지
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    • 제36권4호
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    • pp.274-285
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    • 2023
  • This study was conducted to select representative agricultural products (4 types of fruits and 4 types of wild vegetables) in Chungju, define their sensual characteristics, derive suitable flavour-pairing and recipes for each ingredient, and use them as a cornerstone in the development of menus. For the experiment, 10 experts were selected to choose 8 representative agricultural products in Chungju, and 18 menus were selected through a flavour-pairing survey. A consumer panel (a total of 413 people, 105 in their 20s, 103 in their 30s, 103 in their 40s, and 102 in their 50s) for evaluating the characteristics of consumer preferences was selected. After the flavour-pairing survey 'sweet taste', 'light flavour', 'soft flavour', 'savoury flavour', 'familiar flavour', 'harmonious flavour', 'softness', and 'harmoniousness with food ingredients' were determined as drivers of liking, on the other hand, 'disturbance with food ingredients' and 'soybean fishy smell' were determined as drivers of disliking. The degree of consumer preference and overall acceptance were found to be related to the consumers' familiarity, suggesting that if a menu should be developed using unfamiliar local agricultural products, it should be configured with familiar recipes and seasoning methods.

베타분포를 이용한 서울 지점 연 최대치 독립 호우사상의 대표 시간분포 특성 분석 (Analysis on the Characteristics about Representative Temporal-distribution of Rainfall in the Annual Maximum Independent Rainfall Events at Seoul using Beta Distribution)

  • 전창현;유철상
    • 한국수자원학회논문집
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    • 제46권4호
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    • pp.361-372
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    • 2013
  • 본 연구에서는 1961~2010년 사이의 서울 지점 연 최대치 독립 호우사상들을 베타분포로 분석하여 서울지점의 대표 호우사상을 결정하였다. 구체적으로 살펴보면, 먼저, 첨두강우량을 기준으로 연최대치 호우사상들을 상위 50%와 하위 50%로 구분한다. 각각의 경우에 대해 첨두강우량의 평균을 지나는 베타분포를 유도한다. 마지막으로, 유도된 두 베타분포의 산술평균을 우량주상도로 나타내어 대표 호우사상을 결정한다. 이렇게 유도된 대표 호우사상은 실제 호우사상과 유사한 모양을 갖는 것으로 확인되었으며, 특히 Huff 분포에 비해 큰 첨두 강우량을 갖는 것으로 확인되었다. 여러 강우시간분포 모형들과 비교해 본 결과 Keifer & Chu 모형이 본 연구의 결과와 가장 유사한 것으로 나타났다.