• 제목/요약/키워드: Dimensional nature

검색결과 368건 처리시간 0.033초

Two-dimensional Nature of Center-of-mass Excitons Confined in a Single CdMnTe/CdTe/CdMnTe Heterostructure

  • Lee, Woojin;Kim, Minwoo;Yang, Hanyi;Kyhm, Kwangseuk;Murayama, Akihiro;Kheng, Kuntheak;Mariette, Henri;Dang, Le Si
    • Current Optics and Photonics
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    • 제2권6호
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    • pp.589-594
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    • 2018
  • We have investigated the dimensional nature of center-of-mass exciton confinement states in a CdMnTe/CdTe/CdMnTe heterostructure, where the CdTe well is too wide (144 nm) to confine both electrons and holes but able to confine whole excitons in the center-of-mass coordinate. Fine multiple photoluminescence spectra with a few meV separation were observed at 6 K. From the thickness dependence of the transition rate, they were attributed to even numbered center-of-mass exciton confinement states (N = 2, 4, 6, ${\cdots}$, 18). Dimensionality of the center-of-mass exciton confinement states was also investigated in terms of temperature dependence of radiative decay time. At low temperatures (${\leq}12K$), we found that the ground state excitons are likely localized possibly due to the barrier interface fluctuation, resulting in a constant decay time (~350 ps). With increased temperature (${\geq}12K$), localized excitons are thermally released, giving rise to a linear temperature dependence of radiative decay time as an evidence of two-dimensional nature.

Composition,Dimensional Issue and Nature of Entrepreneurial Orientation (EO) Construct

  • Gupta, Rakesh;Sebastian, V.J.
    • 아태비즈니스연구
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    • 제5권1호
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    • pp.23-31
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    • 2014
  • Entrepreneurship is considered as an important driver of economic growth, new firm creation, business rejuvenation& job creation. Over a period of time research within entrepreneurship literature has shifted from entrepreneur and his personality to his behavioral disposition. This has led to emergence of entrepreneurial orientation (EO) construct, which focuses on the process of entrepreneurship at firm level and it has emerged as the most widely researched area within entrepreneurship field. Though research in this field has been rigorous and exhaustive, still there have been concerns that researchers might have prematurely agreed on the composition, dimensionality, and nature of EO Construct. There has been considerable debate about whether EO Construct comprises three or five dimensions, about co-variance or independence of these dimensions and nature of construct whether formative or reflective. This article builds an argument about the multidimensional nature of EO construct comprising five dimensions, which vary independently and the fact that EO is better explained through formative construct rather than reflective one.

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Model Predicitve Control of First Order Hyperbolic PDE Systems

  • Park, Jinhoon;Lee, Kwang-Soon
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.46.3-46
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    • 2002
  • Most of the process control algorithms in practice are based on the finite dimensional control theory. However, many chemical processes are described by partial differential equations (PDE's) and are infinite dimensional in nature due to spatial variation. Especially when the convection is dominant and thus diffusion can be ignored, chemical processes that are described by a system of first order hyperbolic PDE's. Such processes include tubular reactors, fixed bed reactors and pressure swinging adsorption. Conventionally such infinite dimensional systems described by PDE's are controlled by finite dimensional controllers that are designed through finite dimensional reduction of the process m...

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브랜드 아파트에 나타난 자연친화적 외부공간의 디자인 특성에 관한 연구 (Nature-Friendly Design Characteristics of Outdoor Spaces in Brand Apartments)

  • 황연숙;이송현
    • KIEAE Journal
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    • 제13권1호
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    • pp.93-100
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    • 2013
  • A outdoor space of the brand apartment can improve the quality of the whole environment in apartment and has differentiated identity in apartment housing through various versions of the green space and water space plan. The purpose of this study is to evaluate nature-friendly design characteristics in brand apartments and to offer a basic information for planning of brand apartment. In concrete, nature-friendly design did by green space and water space that can analyze by visual, and investigation contents divided to position, form, user behavior, link space from user viewpoint by case study. This study examined a case of eight brand apartments located in Gangnamgu, Seoul. We has divided the characteristics of a green space into horizontal type, vertical type, multi-dimensional type and has divided the water space into stagnant water type, flowing stream type, waterfall type and fountain type. The findings are summarized as follows: First, in case of the space of brand apartment, the application of horizontal and vertical greenery was lower compare with multi-dimensional green space. The most of items for multi-dimensional greenery have been planned to the open space and promenade. Second, a stagnant water type of water space features well used in most of the cases but a water space of signs of activity like a flowing stream, waterfall, fountain types were underused because of problem of administrative and maintenance expenses. Thirdly, Water space of brand apartments was planned with specialization item by apartment housing but green space does not have differentiated item and was planned by most similar form.

과도기적 위치의 워즈워스: 정신과 자연의 상호 작용 모색 (Wordsworth of Transitional Position : Seeking Interaction between Mind and Nature)

  • 황병훈
    • 영미문화
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    • 제17권2호
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    • pp.89-109
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    • 2017
  • This study focuses upon the fact that Wordsworth has a great interest in the epistemological understanding of nature. It denies that his early poems, such as An Evening Walk and Descriptive Sketches, only represent the subtleties of nature, according to the picturesque mode of the eighteenth century, without any other consideration about human mind. It tries to trace his effort to deal with the relationship between nature and mind, which is committed to the apprehension of Wordsworth's experience which shapes much of his later work. Prior to Wordsworth, or in his earlier days, both the picturesque description and the descriptive poetry tend to be two-dimensional. Staying away from the cold rules of painting and overcoming passivity, he prefers to contemplate nature through his emotions and tries to come close to the sublime sense. Therefore, his poetic strategy is to show that his poetic description of nature goes beyond the limits which these picturesque rules and colors impose. His readers get the feeling of how desperate he become trying to choose the suitable poetic language to express the relationship between nature and mind. He also has an interest in developing a character, Dorothy, to match what he thinks and to mediate what he intends to describe through his epistemological understanding of nature.

지속가능한 발전의 사회학적 고찰 (A Sociological Approach to Sustainable Development)

  • 정대연
    • 환경영향평가
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    • 제12권1호
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    • pp.55-72
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    • 2003
  • The term sustainable development is being used widely since WCED suggested it in 1987. This paper aims at catching up its sociological implications. For doing this, the paper examined some major existing researches on sustainable development. It was found that sustainable development has been defined as an economic development with the preservation of nature as an environment of human life. In this sense, the existing concept of sustainable development is an economic perspective. Sustainable development as an economic perspective is faced with some limitations and/or problems. They are summarized as follows. The human-made environment is excluded from the concept of sustainable development. Its ideology is anthroponcentric in that the sustainability of nature is a necessary condition for economic development. The objective reference which can measure whether the current state of nature is sustainable or not is not proposed. Consequently, sustainable development results in merely a survivability of economy, a new form of economic utility and/or a successful economy. In terms of sociological perspective, economy and nature can not be sustainable without other social factors being sustainable, because all social factors including economy and nature exist in a causal mechanism. This means that sustainable development should be approached from a multi-dimensional perspective. The multi-dimensional approach can be a framework of sustainable development in terms of whole society, then can be termed sustainable society which implies not a sustainable development, but a societal development. The factors which should be included in the sustainable society are, at least, nature, economy, population as an aggregate, mode of living existence of people as a cultural actor, technology, and social structure.

다차원 공간 제한 기법의 3차원 비정렬 격자계로 확장 (EXTENSION OF MULTI-DIMENSIONAL LIMITING PROCESS ONTO THREE-DIMENSIONAL UNSTRUCTURED GRIDS)

  • 박진석;김종암
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2010년 춘계학술대회논문집
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    • pp.404-411
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    • 2010
  • The present paper deals with the continuous work of extending multi-dimensional limiting process (MLP), which has been quite successfully proposed on two- and three-dimensional structured grids, onto the unstructured grids. The basic idea of the present limiting strategy is to control the distribution of both cell-centered and cell-vertex physical properties to mimic a multi-dimensional nature of flow physics, which can be formulated as so called the MLP condition. The MLP condition can guarantee a high-order spatial accuracy without yielding spurious oscillations. Recently, MLP slope limiter was proposed based on the MUSCL-type reconstruction in two-dimensional case and it can be readily extended to three-dimensional case. Through various numerical analyses and extensive computations, it is observed that the proposed limiters are quite effective in controlling numerical oscillations and very accurate in capturing both discontinuous and continuous multi-dimensional flow features on 3-D tetrahedral grids.

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Delicate Difference in Coordinating Nature between Copper(II) and Nickel(II) Ions. Structural Properties of Copper(II) and Nickel(II) Nitrate Containing 1,2-Bis(dimethyl-3-pyridylsilyl)ethane

  • Kim, Shin-A;Kim, Chi-Won;Noh, Tae-Hwan;Lee, Young-A;Jung, Ok-Sang
    • Bulletin of the Korean Chemical Society
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    • 제31권8호
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    • pp.2158-2162
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    • 2010
  • Studies on the molecular construction and structures of $M(NO_3)_2$ (M = Cu(II), Ni(II)) complexes with 1,2-bis(dimethyl-3-pyridylsilyl)ethane (L) have been carried out. Formation of each molecular skeleton appears to be primarily associated with a suitable combination of bidentate N-donors of L and coordinating nature of octahedral metal(II) ions: [$Cu(NO_3)_2(L)_2$] yields a 2-dimensional sheet structure consisting of 44-membered $Cu_4L_4$ skeleton whereas $[Ni(L)_2(H_2O)_2](NO_3)_2$ produces an interpenetrated 3-dimensional structure consisting of 66-membered cyclohexanoid ($M_6L_6$) skeleton. The Cu(II) ion prefers nitrate whereas the Ni(II) ion prefers water molecules as the fifth and the sixth ligands.

The Relationship Between Visitors' Environmental Attitudes and Their Recreational Motivations: A Case Study in a Korean National Park

  • Shin, Won Sop;Kwon, Heon Gyo;Han, Hang Yeol
    • 한국산림과학회지
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    • 제98권2호
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    • pp.163-169
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    • 2009
  • This study examines the relationships between visitors' environmental attitudes as measured by the new environmental paradigm (NEP) and their recreational motivations based on data collected from a national park in South Korea. The data analysis indicated that visitors' environmental attitudes and motivation were multi-dimensional structures. The NEP composed of three factors named 'Humans over Nature', 'Balance of Nature', and Limit to Growth'. Visitors' motivation also composed of four factors representing 'Achievement and Stimulation', 'Escape and Enjoying Nature', 'Social and Leadership', and 'Family'. However, there were significant correlations among the factors, suggesting they were independent each other. There were also significant differences in visitors' motivation due to their level of environmental attitudes.

자연친화적인 공원시설 설치를 위한 정책방향 - 국립공원 공원시설의 자연친화성 평가를 근거로 - (Policy Directions to Build on Nature-Friendly Park Facilities - Based on an Evaluation on the Nature-Friendliness of Park Facilities in National Parks -)

  • 박창석;배민기;김태진
    • 한국조경학회지
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    • 제37권5호
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    • pp.1-12
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    • 2009
  • 본 연구의 목적은 국립공원 내에 자연친화적인 공원시설의 설계와 설치를 위한 정책방향을 제시하는 것이다. 이를 위해서 국내 외 친환경건물 인증제도와 관련 연구에 대한 고찰을 통해 입지, 설계와 설치, 운영과 관리부분별로 자연친화성 평가지표를 개발하였다. 본 연구에서는 19개 국립공원의 26개 공원사무소에서 실제 시설을 관리하고 있는 공원관리자 79명을 대상으로 한 설문조사를 통해 자연친화성 평가를 위한 자료를 수집하였다. 분석방법은 기술분석, 집단간 평균의 차이분석, 다차원척도법, 요인분석을 활용하였다. 분석결과, 1) 자연친화성 평가지표들 간의 상대적 중요도를 산정한 결과, 시설의 입지 관련지표의 중요도가 가장 높게 나타났다. 2) 공원시설의 자연친화성 수준에 대한 평가 결과, 입지 관련 지표들의 자연친화성 수준이 가장 높게 나타난 반면, 시설의 설계 및 설치 관련 지표들의 수준이 낮게 평가되었다. 특히, 에너지 효율화와 관련된 지표들의 평가값이 가장 낮게 나타났다. 3) 시설별로 보면, 대피소의 자연친화성이 가장 높게 나타난 반면, 휴게소의 자연친화성이 가장 떨어지는 것으로 평가되었다. 4) 전반적으로 볼 때, 설악산, 오대산, 태안해안국립공원의 공원시설에 대한 자연친화성 수준이 높게 나타난 반면, 경주와 속리산 국립공원의 자연친화성 수준은 떨어지는 것으로 평가되었다. 본 연구 결과는 자원절약 및 자연생태계와 공원자원을 보존하고 탐방객의 편리한 이용을 위한 자연친화적인 공원시설 설치를 위한 권고기준을 마련하는데 활용될 수 있을 것이다.