• 제목/요약/키워드: Space-Time Theories

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EDMS와 기록물의 라이프사이클 (EDMS and Life-cycle of Records)

  • 김익한
    • 기록학연구
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    • 제5호
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    • pp.3-37
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    • 2002
  • Today the market of EDMS is esteemed more than 100 billions won. It signifies a comming of age of electronic records. The traditional archival theories which are based on the paper records are confronted with a new challenge. In some leading countries of archival studies reorientation of archives management has been tried by a number of distinguished specialists such as Bearman and Hedstrom since 10 years. As a consequence new paradigm of archival theories has been developed. Also in Korea this new paradigm has been introduced by some expert such as Lee, Sang-Min, Sul, Moon-won, Lee, Seung-Eok. However their arguments are too general to offer a concrete clue for new paradigm. Faced by new age of electronic records, it's important to start a discussion for the reasonable methods of electronic records management at once. The most drastically changed part of record management by the electronic technique is the life-cycle of records. The commonly practiced three-stage life-cycle is to be reduced to the two-stage life-cycle, and the concept of the spatial movement of records is to be changed. It can be also pointed that the public emerges as user from the early creating stage of records beyond time and space. Thus is can be said that the method of the management features dynamic and cohesive. The method of appraisal must be also changed and reproduced, so that it can reflect the various levels considering dynamics of the electronic records. Supposedly it will be a core factor that causes the change of methodology in records management with the change of life-cycle theory. It must be noted that various subjects would be involved in the work of classification and description over time and space and that feedback between them is of important. Description also tends to be made at the crating stage of records and structured dynamically. It results from the change of life-cycle and the introduction of the concept of continuum. Such trend allows us to start discussions on the assumption that description of both creator and archival professionals act together an important role. Of course, it is linked with the methodology in which most descriptions are made automatically at the early drafting stage of the structure. The meat date is formed on the assumption that there should be feedback between areas of automatic description, description of creators and archival professionals. The most important thing in description is to develop a suitable way how it is structured. An alternative must be offered for managing data set. As iweb that is being operated by Myongji university shows, records created in daily business are managed not as electronic records but as date base. This is because they exist outside the repository in the EDMS system. Since data set often has various sources, an alternative for classification needs to be developed. It is now likely that database is filed according to the created year to be transferred automatically to the repository. Over a long-term the total management of database, electronic records and electronic information will be a topic. A right direction of new paradigm will be found for both iweb and E-government, when practice and studies of theories are combined and interacted.

Empirical Design of an On and Off Type Solenoid Actuator For Valve Operation

  • Sung, Baek-Ju;Lee, Eun-Woong;Kim, Hyoung-Eui
    • KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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    • 제4B권2호
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    • pp.39-46
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    • 2004
  • Modern users demand that the on and off type solenoid actuator should be smaller, lighter in weight, lower in consumption power, and higher in response time. The complete design satisfying such requirements can be achieved when electromagnetic theories and empirical knowledge are combined. This paper presents various types of empirical coefficients essentially needed for optimal design of a solenoid actuator. The values of these empirical coefficients are obtained through extensive experiments over a great length of time for various kinds of solenoid actuators. We have developed a design program that is composed by combination of governing equations and empirical coefficients, and have also manufactured a prototype solenoid actuator based on the final results of the design program. The propriety of the design program and empirical coefficients have been proven by experiments.

GENERALIZED THERMOELASTICITY WITH TEMPERATURE DEPENDENT MODULUS OF ELASTICITY UNDER THREE THEORIES

  • Ezzat, M.;Zakaria, M.;Abdel-Bary, A.
    • Journal of applied mathematics & informatics
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    • 제14권1_2호
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    • pp.193-212
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    • 2004
  • A new model of generalized thermoelasticity equations for isotropic media with temperature-dependent mechanical properties is established. The modulus of elasticity is taken as a linear function of reference temperature. The present model is described both generalizations, Lord Shulman (L-S) theory with one relaxation time and Green-Lindsay (G-L) with two relaxation times, as well as the coupled theory, instantaneously. The method of the matrix exponential, which constitutes the basis of the state space approach of modern control theory, applied to two-dimensional equations. Laplace and Fourier integral transforms are used. The resulting formulation is applied to a problem of a thick plate subject to heating on parts of the upper and lower surfaces of the plate that varies exponentially with time. Numerical results are given and illustrated graphically for the problem considered. A comparison was made with the results obtained in case of temperature-independent modulus of elasticity in each theory.

Rotational State Distribution of CO₂ after a Collision with H Atom

  • 김유항;김성훈
    • Bulletin of the Korean Chemical Society
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    • 제16권7호
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    • pp.644-648
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    • 1995
  • Based on the collisional time correlation function (CTCF) formalism, Kim and Micha derived a simple expression which gives nascent rotational state distribution of molecules after collision with fast atoms.32 The expression is valid when the collision time is short and the collision is impulsive in nature. This expression has been applied to analyze the experimentally measured, state resolved rotational distribution of CO2 in various types of vibrational levels, i.e., (0001), (0111), (0002), and (1000/0200). The theoretical distributions obtained from this CTCF based expression can represent the experimentally measured rotational distributions remarkably well, and have been found to be much superior to those obtained from other simple theories such as Boltzmann distribution, prior distribution, breathing ellipsoid model, and phase space statistical calculation.

Information Processing in Primate Retinal Ganglion

  • Je, Sung-Kwan;Cho, Jae-Hyun;Kim, Gwang-Baek
    • Journal of information and communication convergence engineering
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    • 제2권2호
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    • pp.132-137
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    • 2004
  • Most of the current computer vision theories are based on hypotheses that are difficult to apply to the real world, and they simply imitate a coarse form of the human visual system. As a result, they have not been showing satisfying results. In the human visual system, there is a mechanism that processes information due to memory degradation with time and limited storage space. Starting from research on the human visual system, this study analyzes a mechanism that processes input information when information is transferred from the retina to ganglion cells. In this study, a model for the characteristics of ganglion cells in the retina is proposed after considering the structure of the retina and the efficiency of storage space. The MNIST database of handwritten letters is used as data for this research, and ART2 and SOM as recognizers. The results of this study show that the proposed recognition model is not much different from the general recognition model in terms of recognition rate, but the efficiency of storage space can be improved by constructing a mechanism that processes input information.

교실 연구의 최근 동향과 '교실 공간 메타포' 연구 (A Study on the 'Classroom Space Metaphors' in Classroom Research)

  • 한희경
    • 대한지리학회지
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    • 제44권6호
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    • pp.833-851
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    • 2009
  • 최근 국내외에서 교육의 현장에 대한 이해가 절실해지면서 '교실'에 대한 관심이 크게 부상하고 있다. 본 연구는 영어권을 중심으로 교실 연구의 최근 동향을 검토한 다음, 교실의 이해를 위해 긴요하지만 지금까지 다분히 간과되어 온 주제로서 '교실의 공간성' 문제를 제기하고 이를 '교실 공간 메타포'를 통해 접근하는 데에 목적이 있다. 이를 위해 먼저 영어권의 최근 동향에 주목하면서 최근의 교실 연구에서는 교실 그 자체를 수단이 아닌 목적으로 다루고 있으며 방법론에 있어서도 모종의 전환을 보이고 있다는 점을 확인할 수 있었고, 이를 근거로 최근의 일단의 교실 연구들을 염두에 두고 '교실론'의 설정 가능성을 제안하였다. 다음으로 최근의 교실론의 지평을 확장함에 있어서 매우 중요하면서도 다분히 간과되었던 주제가 바로 '교실의 공간성'에 대한 논의임을 제기하였다. 여기에 접근하기 위해 연구자는 '메타포' 개념을 동원하였고, 전통적 교실 연구에서 상정하는 교실 공간 메타포를 크게 '작업장으로서의 교실'과 '연극 무대로서의 교실'로 범주화할 수 있었다. 그리고, 최근의 교실론을 바탕으로 '삶의 공간으로서의 교실'이라는 새로운 메타포를 제시하면서 여기에 내포된 교육적 함의를 제3공간에 대한 논의와 연결시켜 도출해 보고자 하였다.

Wide-field and Deep Survey of Nearby Southern Clusters of Galaxies

  • 이수창;성언창;;;정애리;김석;이영대
    • 천문학회보
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    • 제36권2호
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    • pp.121-121
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    • 2011
  • Thanks to KMTNet's wide field of view, it is time to implement imaging survey of extensive area of clusters of galaxies in the southern sky with modern instrument. As part of potential long-term survey of nearby (D < 50 Mpc) well-known clusters of galaxies, we propose a wide-field and deep survey of Fornax cluster as a first step of the project. By imaging the 400 square deg region (100 fields) enclosed within the five times virial radius of the Fornax cluster, in three SDSSfilters(g', r', i'), we can provide an unprecedented view of structure of Fornax cluster using sample from giant to dwarf galaxies. We will secure galaxies with brightness comparable to the limiting magnitude (r'=23.1 AB mag) of SDSS. Furthermore, we also request extremely deep (limiting surface brightness of ~ 28 mag $arcsec^{-2}$forr'band) survey for the central region (16 square degree, i.e., four fields) of Fornax cluster. This will allow us to detect the diffuse intracluster light (ICL) that permeates clusters as a valuable tool for studying the hierarchical nature of cluster assembly. In order to complete whole survey, about 285 hr observing time (without overhead) is required. By combining data available at other wavelengths, it will offer unique constraints on the formation of large-scale structure and also provide important clues for theories of galaxy formation and evolution. Our proposed survey will be implemented in the close collaboration with researchers in various countries (Germany, Australia, UK, USA) and ongoing project (e.g., SkyMapper).

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미의 기준과 공간 특성의 상관관계에 대한 역사적 연구 - 그리스.로마 및 르네상스를 중심으로 - (A Historical Research on Correlation between the Standard of Beauty and Spatial Characteristics - Focusing on Greek.Rome and Renaissance -)

  • 이철재
    • 한국실내디자인학회논문집
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    • 제19권6호
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    • pp.141-149
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    • 2010
  • This thesis is designed to take a close look into the characteristics of architectural space through the standard of beauty, which has been created apart from our desires at certain cultural or historical periods of time. It will try to construct the outline of conception about the beauty throughout many centuries. First of all, contents of the research will focus on the aspects, which people have been considering as beauty eversince the ancient time without having any assumptions on its concept. For example, if the beauty of art has been accepted by the theories of modern aesthetics while degrading the beauty of nature, its value could have possibly been much more appreciated. The standard of beauty has been going through the process of change in such history of mankind. The general standard of beauty, which was established in the ancient time was the proportion and harmony between many elements. Afterwards, beauty was expressed as colors and light in medieval times. Expression of beauty using ugly features such as monsters or demons also existed at the time. Beauty has been periodically developing from supernatural to gracious, rational, noble, romantic, religious, mechanical, and today's media. The concept of beauty established from the above has been appearing throughout various culture such as dress and decoration at the given period of time. It would later affect the formation of space as well as decoration for architectures and styles. It will be analyzed throughout the five design elements; style, composition, materials, components, and form. The thesis would like to find the spatial order of beauty from the result of the analysis. The analysis will examine the possibility for which the recomposition of beauty will be provided as a design process for the new era. The Greek beauty represents a shape. The shape represents proportion and the proportion represents given numbers. However, beauty is being expressed by the opposite process at the present time. In other words, computers will arrange the numbers, which would formalize the proportion between the numbers. Beauty would be presented when the shape is presented as certain forms.

원대(元代)와 세종대(世宗代) 자동 물시계 시보시스템 비교 (COMPARISON OF THE TIME-SIGNAL SYSTEM OF AUTOMATIC WATER CLOCKS DURING THE YUAN DYNASTY AND THE KING SEJONG ERA OF THE JOSEON DYNASTY)

  • 윤용현;김상혁;민병희;임병근
    • 천문학논총
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    • 제39권1호
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    • pp.1-12
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    • 2024
  • In this study, we investigated the time signal devices of Deungnu (circa 1270) and Gungnu (1354), the water clocks produced during the Yuan Dynasty (1271-1368). These clocks influenced Heumgyeonggaknu (1438) of the Joseon Dynasty (1392-1910), exemplifying the automatic water clocks of the Yuan Dynasty. Deungnu, Gungnu, and Heumgyeonggaknu can be considered as automatic mechanical clocks capable of performances. The Jega-Yeoksang-Jip (Collection of Calendrical and Astronomical Theories of Various Chinese Masters) contains records of Deungnu extracted from the History of the Yuan Dynasty. We interpreted these records and analyzed reproduction models and technical data previously produced in China. The time signal device of Deungnu featured a four-story structure, with the top floor displaying the four divine constellations, the third floor showcasing models of these divinities, the second floor holding 12-h jacks and a 100-Mark ring, and the first floor with four musicians and a 100-Mark Time-Signal Puppet providing a variety of visual attractions. We developed a 3D model of Deungnu, proposing two possible mechanical devices to ensure that the Time-Signal Puppet simultaneously pointed to the 100-Mark graduations in the east, west, south, and north windows: one model reduced the rotation ratio of the 100-Mark ring to 1/4, whereas the other model maintained the rotation ratio using four separate 100-Mark rings. The power system of Deungnu was influenced by Suunuisangdae (the water-driven astronomical clock tower) of the Northern Song Dynasty (960-1127); this method was also applied to Heumgyeonggaknu in the Joseon Dynasty. In conclusion, these automatic water clocks of East Asia from the 13th to 15th centuries symbolized creativity and excellence, representing scientific devices that were the epitome of clock-making technology in their times.

Role of Mass Inflow and Supernova Feedback on Nuclear Ring Star Formation

  • Moon, Sanghyuk;Kim, Woong-Tae;Kim, Chang-Goo;Ostriker, Eve C.
    • 천문학회보
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    • 제46권2호
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    • pp.37.1-37.1
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    • 2021
  • Observations suggest the star formation in nuclear rings of barred galaxies proceeds episodically in time and sometimes asymmetrically in space. Existing theories and numerical simulations suggest that the episodic star formation is perhaps due to either supernova feedback combined with fluid instabilities or time-varying mass inflow rate. However, it has been challenging to discern what dominates in shaping the star formation history because the effects of the inflow and feedback are blended in global simulations of nuclear rings. To understand their effects separately, we construct semi-global models of nuclear rings, which treat the mass inflow rate as a model parameter. By running simulations with the inflow rates kept constant or oscillating in time, we find that the star formation rate (SFR) of the rings varies coherently with the inflow rate, while the feedback is responsible only for stochastic fluctuations of the SFR within a factor of two. The feedback instead plays an important role in maintaining the vertical dynamical equilibrium and setting the depletion time. While the asymmetry in the inflow does not necessarily lead to the asymmetry in the star formation, we find that the rings undergo a transient period of lopsided star formation when the inflow rate of only one dust lane is suddenly increased.

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