• Title/Summary/Keyword: the imaginary

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Vibrational Assignment of S$_8$ from Normal Coordinatie Analysis

  • Chang, Man-Chai;Kim, Hyun-Yong;Jhon, Mu-Shik
    • Bulletin of the Korean Chemical Society
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    • v.6 no.1
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    • pp.29-32
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    • 1985
  • Normal modes of crystalline orthorhombic sulfur belonging to the space group $D_{2h}$-Fddd, have been evaluated by taking the lowest temperature phase in the solid. Normal modes are obtained by the valence force field with modified force constants and a quantitative description of the mode is adjusted by the potential energy distribution. Since the full crystal system of orthorhombic sulfur is so large, we intended to calculate the normal modes simply by constructing the imaginary box made by the infinite mass boundary. And the Raman experiment is done by using the more powerful Ar-Kr gas laser with lowering the temperature to ${\sim}10^{\circ}K$.

Controller design to diminish oscillation and steady state error in water temperature systems with drive delay

  • Nakamura, Masatoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1888-1893
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    • 1991
  • Systematic design of a controller for a water temperature system was considered, with the intention of devising an accurate control experiment. The results of an experiment using a water temperature system based on the pole placement regulator showed water temperature oscillation and steady state error. This paper proposed a. method for eliminating both the oscillation and the steady state error. The oscillation was eliminated by a drive delay compensation technique, in which a future state value of the system was predicted through a real time computer simulation. The steady state error was eliminated by an steady state error correction technique, in which an actual steady state heatrate in the system model was replaced by an imaginary heatrate. By combining these two techniques, we obtained an experimental result for water temperature control of 0.01 (.deg. C) accuracy. Furthermore, the proposed method was evaluated relatively by comparing the experimental results using several other methods and proved to be the most accurate and convenient control method for the delay system.

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College Students Knowledge and Attitudes Toward AIDS in Pusan and Ulsan Areas (부산 및 울산지역 일부 대학생들의 에이즈에 대한 지식과 태도 조사)

  • 신영희;홍영혜
    • Journal of Korean Academy of Nursing
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    • v.26 no.1
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    • pp.33-42
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    • 1996
  • Given the global impact of the AIDS pandemic, it is necessary to take every measure to prevent an epidemic of this disease in Korea. The only available strategy is prevention. Considering college students as a potential risk group, this study examined their knowledge of, and attitudes toward AIDS. In this study, 399 students from three colleges in Pusan and Uoolsan were examined for their attitudes to, and knowledge of AIDS. Findings indicate that the majority of the students(90%) had basic knowledge on the transmission and the prevention of the disease. However, most of them, including nursing students, lacked knowledge as to the etiological agent, major symptoms and available diagnostic techniques. To the questions designed to examine social attitude towards AIDS patients, the students showed a tendency to view AIDS patients as responsible for their own illness. Interestingly, they showed sympathy to their imaginary friends and relatives suffering from AIDS. The study findings suggest a need for the development of AIDS educational programs for college students.

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An Electrical fire Diagnosis System Using the Mixed Approach of the Case-Based Reasoning with the Knowledge-Based Reasoning (지식기반 추론과 사례기반 추론의 혼합 적용 기법을 이용한 전기화재 원인진단 시스템)

  • 권동명;김두현;김상철;김상렬
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 1999.06a
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    • pp.223-228
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    • 1999
  • This paper presents an electrical fire diagnosis system using intellectual reasoning which is the mixed approach of the case-based reasoning with the knowledge-based reasoning A prototype system is implemented using Delphi, one of the program development tools under windows environment, for making an application program for database. And database is builded using Paradox. The results of applying the system to some imaginary fire cases to verify its capability and validity show that the causes of fires is successfully diagnosed, so the proposed system proves to be reasonable.

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A Study on the Conception of Planarity in Modern Art (근대 건축에서의 '평면성' 개념)

  • Lee, Kwang-In
    • Journal of The Korean Digital Architecture Interior Association
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    • v.7 no.2
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    • pp.59-65
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    • 2007
  • This study is aimed to find out the conception of planarity in Modern Architecture. Some architecture historians such as Hildebrand and Schmarsow indicated the planarity by which new idea of space in architecture was made. The characteristics of the planar was embodied and developed through the proclamation of the ideology and their works in the avant-garde art movement of Cubism and Neoplasticism. The planarity in modern architecture was embodied from various aspects -the perception of space, the pictorial art and the metaphysics- by means of imaginary plane, superposition of planes, oscillation of plane, deconstruction of mass and elimination of natural color.

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Effect of Rare Earth (Gd, Er) on the Permeabilities of Ba-Ferrite (회토류(Gd, Er)첨가가 Ba 페라이트의 투자율에 미치는 영향)

  • 정승우;김태원;최우성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.10
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    • pp.887-894
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    • 2000
  • In this paper, we have studied the effect of earth (Gd, Er) on the various properties (microstructure, shrinkage, initial permeability, permeability as a function of frequency, etc) of Ba-ferrite. The permeabilities were analyzed by Impedance Analyzer(100KHz~40MHz) and Network Analyzer(30KHz~3㎓). As the result of XRD, all of the Ba-ferrite doped with rat earth was found to be Y-hexagonal phase. The resonance frequencies at the maximum imaginary value of complex permeability were observed near 2㎓. The complex permeabilities of the Ba-ferrite doped with Gd$_2$O$_3$at 3wt% and doped with Er$_2$O$_3$at 3wt% and 5wt% as a function of frequency showed the highest value at sintered temperature at 95$0^{\circ}C$/3h.

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Red Shift of the Raman (FBCARS) Excitation Profile of Iodine from the Absorption Spectrum(I)

  • Lee, Mu-Sang;Carreira, L.A.
    • Bulletin of the Korean Chemical Society
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    • v.7 no.1
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    • pp.59-62
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    • 1986
  • Folded Box coherent anti-Stokes Raman spectroscopy (FBCARS) spectra of the fundamental symmetric stretch(213 $cm^{-1}$) and the first overtone(421 $cm^{-1}$) of $I_2$ have been recorded over the pump wavelength range from 495 nm to 580 nm. The lineshapes were fitted using the least squares method and the A and C term of CARS were calculated. From the fitting of A and C terms, the real(R) and imaginary(I) term intensity of CARS were calculated using harmonic oscillator program. The calculated CARS excitation profile of $I_2$ with R and I term data was about 270 $cm^{-1}$ red shifted from the absorption spectrum.

Alternative Potentials Analyzing the Scattering Cross Sections of 7,9,10,11,12,14Be Isotopes from a 12C target: Proximity Potentials

  • Aygun, M.
    • Journal of the Korean Physical Society
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    • v.73 no.9
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    • pp.1255-1262
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    • 2018
  • In this paper, alternative potentials to explain the scattering cross sections of $^{7,9,10,11,12,14}Be$ isotopes by a $^{12}C$ target nucleus at different energies are researched. For this purpose, fourteen different proximity potentials, such as Proximity 1966, Proximity 1976, Proximity 1977, Proximity 1979, Proximity 1984, Proximity 1988, Proximity 1995, Broglia and Winther 1991, Aage Winther, Bass 1973, Bass 1977, Bass 1980, Christensen and Winther 1976, and $Ng{\hat{o}}$ 1980, are used to produce the real potential within the optical model. The imaginary potential is formed by using the Woods-Saxon potential. The theoretical results are compared with both experimental data and data reported in the literature. The results are in good agreement with the data. The proximity potentials are observed to play a significant role in obtaining the scattering cross sections of $^{7,9,10,11,12,14}Be$ isotopes.

Schwinger Pair Production via Polons and the Origin of Stokes Phenomena

  • Kim, Sang Pyo
    • New Physics: Sae Mulli
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    • v.68 no.11
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    • pp.1225-1230
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    • 2018
  • Schwinger pair production of electrons and positrons in a strong electric field is a prediction of nonperturbative quantum field theory, in which the out-vacuum is superposed of multi-particle states of the in-vacuum. Solving the Dirac or Klein-Gordon equation in the background field, though a linear wave equation, and finding the pair-production rate is a difficult or nontrivial job. The phase-integral method has recently been introduced to compute the pair production in space-dependent electric fields, and a complex analysis method has been employed to calculate the pair production in time-dependent electric fields. In this paper, we apply the complex analysis method to a Sauter-type electric field and other hyperbolic-type electric fields that vanish in the past and future and show that the Stokes phenomena in pair production occur when the time-dependent frequency for a given momentum has finite simple poles (polons) with pure imaginary residues.

The Body Shape and 3D Humanbody Model for the Electronic Commerce of the Clothing Manufacture of College Women in their Twenties (의류제품(衣類製品)의 전자상거래(電子商去來)를 위한 20대(代) 여대생(女大生)의 체형(體型) 및 3D 인체(人體) 모형(模型))

  • Kim, Hyo-Sook;Lee, So-Young
    • Journal of Fashion Business
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    • v.8 no.4
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    • pp.94-103
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    • 2004
  • The purpose of this study was to make activated electronic business transaction of clothes. The subject used for this study was 19 - 24 aged 149 college women who most likely buying products through internet. By compare the 149 women's body shape with 3D model, 149 women could be judged their body shape objectively. We showed the average 3D model by the measurement of 19 - 24aged women's body shape. 19 - 24aged women are big customer of internet shopping mall. By understanding of the difference between real somatotype and perceptual somatotype, we can reduce the disadvantage such as returning clothes. Also, imaginary fitting model can be used for internet shopping mall, animation work, fashion show, and advertisement work. Therefore, we can expect the worth of this study to do.