• Title/Summary/Keyword: time-space distribution

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A Study on Indoor Environment of Interior with Ventilation

  • Kang, Tae-Wook;Koh, Jae-Yoon
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.2
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    • pp.267-274
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    • 2006
  • There are no solar loads through windows and heat transfer from outer walls of the building to the interior This study analyzes indoor air temperature and air flow distribution for the interior of buildings or vessels occupying space. Numerical method is adopted to visualize the indoor side environmental situation. that is without heat transmission to outside the building in various cooling load conditions; supply ventilation lighting. occupancy and infiltration in conditioned spaces. Reaching time of an air conditioner is predicted theoretically by cooling load variations. Theoretical modelling of the reaching time shows good agreement with experimental results.

Analysis of Time-Dependent Behavior of Plasma Sheath using Ion Fluid Model (이온유체방정식을 이용한 Plasma Sheath 시변 해석)

  • Lee, Ho-Jun;Lee, Hae-June
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.12
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    • pp.2173-2178
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    • 2007
  • Dynamics of plasma sheath was analyzed using simple ion fluid model with poison equation. Incident ion current, energy, potential distribution and space charge density profile were calculated as a function of time. The effects of initial floating sheath on the evolution of biased sheath were compared with ideal matrix sheath. The effects of finite rising time of pulse bias voltage on the ion current and energy was studied. The influence of surface charging on the evolution of sheath was also investigated

PWN SED modeling: stationary and time-dependent leptonic scenarios

  • Kim, Seung-jong;An, Hong-jun
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.43.3-43.3
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    • 2018
  • We develop a model for broadband spectral energy distribution (SED) of Pulsar Wind Nebulae (PWNe). The model assumes that electrons/positrons in the pulsar wind are injected into and stochastically accelerated in the pulsar termination shock. We consider two scenarios: a stationary one-zone case and a time-evolving multi-zone case. In the latter scenario, flow properties in the PWNe (magnetic field, bulk speed) are modeled to vary in time and space. We apply the model to the broadband SED of the pulsar wind nebula 3C 58. From the modeling, we find that a broken power-law injection is required with the maximum electron energy of ~200 TeV.

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The Study of Two-dimensional Chemical Distribution about Soil using Laser Spectroscopy (레이저 분광법을 활용한 토양 2차원 화학적 분포도 검출 연구)

  • Yang, Jun-Ho;Yoh, Jai-Ick
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.45 no.6
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    • pp.523-530
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    • 2017
  • Laser-Induced Breakdown Spectroscopy (LIBS) which a plasma is irradiated at a specific wavelength depending on the material when a high-energy laser is irradiated, and a Raman spectroscopy which measures rotation and vibration in molecules as light-scattering phenomenon occurs, are attracting attention as a space exploration technology because of the advantages of high accuracy and real-time analysis, and the ability to perform long-range detection. In this study, the tendency of the laser spectrum according to the change of the soil component was analyzed by laser spectroscopy and the two - dimensional chemical distribution was conducted based on the trend of laser spectrum. We have also established the environment of Mars (4-7 torr) and lunar atmosphere (<1 torr) in experimental setup, to prove that it is possible to measure by difference of soil chemical composition using LIBS and Raman spectroscopy even in artificial space environment.

전자상거래에서 정보탐색경로와 구매의도에 관한 연구 - 라이프스타일 유형을 중심으로 -

  • 황인태;심완섭
    • Proceedings of the Korean DIstribution Association Conference
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    • 2000.10a
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    • pp.131-149
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    • 2000
  • 오늘날 급속한 과학기술의 발달과 더불어 우리들은 새로운 미디어 환경의 변화를 통해 지금까지와는 매우 다른 커뮤니케이션 양식을 목격하고 있다. Harvey(1990)의 시간과 공간의 응축(time-space compression)이란 개념을 굳이 빌리지 않더라도 현대사회의 커뮤니케이션 양식은 이전의 것들과는 전혀 다른 양상을 보이고 있다. 전통적인 4대 매체에 이어 제5의 매체로 자리잡고 있는 인터넷이라는 새로운 매체에 대한 학문적 관심이 필요한 이유는 인터넷이 기존의 매체들과는 본질적으로 다른 구별되는 속성을 지니고 있기 때문이다. (중략)

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일본ME학회 학술대회 참관기

  • 홍승홍
    • Journal of Biomedical Engineering Research
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    • v.9 no.1
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    • pp.135-138
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    • 1988
  • In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality.

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SEQUENTIAL CONFIDENCE INTERVALS WITH ${\beta}-PROTECTION$ IN A NORMAL DISTRIBUTION HAVING EQUAL MEAN AND VARIANCE

  • Kim, Sung-Kyun;Kim, Sung-Lai;Lee, Young-Whan
    • Journal of applied mathematics & informatics
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    • v.23 no.1_2
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    • pp.479-488
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    • 2007
  • A sequential procedure is proposed in order to construct one-sided confidence intervals for a normal mean with guaranteed coverage probability and ${\beta}-protection$ when the normal mean and variance are identical. First-order asymptotic properties on the sequential sample size are found. The derived results hold with uniformity in the total parameter space or its subsets.

Global Theory of Einstein-Cartan Equations - Godel Universe with Torsion -

  • Minn, Ho-Kee
    • Journal of The Korean Astronomical Society
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    • v.9 no.1
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    • pp.9-14
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    • 1976
  • Godel models of the universe filled with fluid are studied in the framework of the Einstein-Cartan theory of gravitation. It is assumed that the models admit a group of motions simply transitive on space-time. The combined effects of spin and rotation(vorticity) are studied with a particular attention to whether the held equations impose any restriction on alignement of spin direction (a polarized spin distribution). The solutions are found explicitly in a closed form, which show that spin components are vanishingly small except in the direction of z-axis (the compass of inertia) in which they can assume an arbitrary distribution.

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A Study on the Characteristics of Public Space in Specialized Restaurants at Domestic Composite Shopping Malls and Department Stores (복합쇼핑몰과 백화점 내 전문식당가의 공유 공간 특성에 관한 연구)

  • Yang, Chul-Sik;Kim, Chung-Ki
    • Korean Institute of Interior Design Journal
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    • v.18 no.4
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    • pp.3-10
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    • 2009
  • Domestic distribution market is in a time of transition for the present. With consumers' diverse demands, the growth of department stores, shopping malls, specialized shops and so on has been taken place radically and the competition among them also has become severe. In order to promptly and positively cope with the radically changing trend of market and the generation of competing business entities, they are necessary to establish a discriminated indoor space plan. With such desires as the expansion of leisure activities based on the increase of personal income and the up-gradation, diversification and individualization of living standard based on economic growth, the dining-out space, one of people's life environments, need a variety of changes. In the past, the specialized restaurants of composite shopping malls and department stores were a mere mediating space of food sale between producers and consumers, but today they become a discriminated and creative indoor space which representing customers' lifestyle. The purpose of this study was to examine the characteristic of public space of specialized restaurants at composite shopping malls and department stores and then present a discriminated spatial marketing strategy in order to find out the direction of its proceeding in the future. Therefore, the purpose of this study was to work out basic data for the development of dining-out contents at the time of appearing diverse composite dining-out spaces in the future and of establishing a renovation plan of specialized restaurants at composite shopping malls and department stores in order to provide customers a space which could satisfy their desires. In this vein, the characteristic and composition of necessary space was analyzed based on the examination of cases. The investigator hopes that study findings are used as basic data for the study on the interrelationship between the sale space and dining-out space of composite commercial facilities and for the establishment of marketing strategy to attract customers.

A Study on Changes in China's Distribution Market and Firms' Response Strategies

  • KIM, Byoung-Goo
    • East Asian Journal of Business Economics (EAJBE)
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    • v.9 no.4
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    • pp.69-80
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    • 2021
  • Purpose - This study investigated the development process of the Chinese distribution industry and analyzed the current status of China's offline and online distribution industries under the development process of the Chinese distribution industry. In addition, the current status of offline distributors in China and representative companies were analyzed as case studies. Research design, data, and methodology - This study analyzed the overall environment of the Chinese distribution industry by using literature data. Then, this study conducted a case analysis using RT Mart and Jingdong, major companies in the distribution industry. Result -The main research results of this study show that the Chinese distribution market has already matured, and retailers are fiercely competing to secure sales and operating profits through various methods such as finding new management methods, improving awareness and customer loyalty by expanding the number of stores. Conclusion -Recently, the characteristic of China's distribution industry is that the boundaries of distribution are breaking down. Chinese retailers are taking strategies to expand the scope of services by erasing the boundaries of distribution. In other words, distribution companies are promoting a borderless distribution strategy in which consumers purchase products online and offline without restrictions on time and space. In addition, small stores in residential areas are on the rise compared to large-scale stores in the city center. The existing distribution industry operates various types of distribution stores to prepare for the post-COVID-19 crisis.