• Title/Summary/Keyword: gap functions

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Spectral Domain Analysis of Input Impedance and Radiation Pattern in Rectangular Microstrip Patch Antenna on Anisotropy Substrates with Airgap (공기 갭을 갖는 이방성 매질 위의 사각 마이크로스트립 패치 안테나의 입력 임피던스와 방사패턴에 대한파수 영역 해석)

  • 윤중한;곽경섭
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.5
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    • pp.187-196
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    • 2003
  • Effects of Airgap and anisotropy substrate on input impedance and radiation pattern of rectangular microstrip patch antenna are studied in terms of an integral equation formulation. The input impedance and radiation pattern of microstrip patch antenna is investigated by using Galerkin's moment method in solving the integral equation. Sinusoidal functions are selected as basis functions, which resemble in the actual standing wave on the Patch. From the numerical results, the variation of input impedance and radiation patterns in the variation of air gap thickness, anisotropy ratio of substrate, and relative permittivity of anisotropy substrate are presented.

Resonant Frequency in Rectangular Microstrip Patch Antenna on Anisotropic Substrates with Airgap and Permittivity Superstrate (공기갭과 유전체 덮개층을 갖는 이방성 기판 위의 마이크로스트립 패치 안테나의 공진 주파수 해석)

  • 윤중한;이상목;곽경섭
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11B
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    • pp.1600-1606
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    • 2001
  • Resonant frequency in rectangular microstrip patch antenna on anisotropic substrates with airgap and superstrate are analyzed. Dyadic Green function is derived for selected anisotropic material by constitutive relation. From these results, integral equations of electric fields are formulated using Fourier transform in space region. The electric field integral equations are discretized into the matrix form by applying Galerkin\`s moment method. Sinusoidal functions are selected as basis functions because they resemble in the actual standing wave on the patch. To verify the validity of numerical result, we compare our result with existing one and get a good agreement between them. From the numerical results, the resonant frequency in the variation of air gap, patch length and anisotropy ratio are presented and analysed.

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Dielectric Cover effect of Rectangular Microstrip Patch Antenna on Uniaxial Substrates with Airgap (공기 갭을 갖는 일축성 매질 위에 마이크로스트립 패치 안테나의 덮개층 영향)

  • Yoon, Joong-Han;An, Gyoo-Chul;Kwak, Kyung-Sup
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.9
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    • pp.29-39
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    • 2001
  • Dielectric cover effect of rectangular microstrip patch antenna on uniaxial substrates with airgap are studied. First, we derive Dyadic Green function for selected anisotropic material by constitutive relation and then formulate integral equations of electric fields using Fourier transform in space region. Using Galerkin's moment method, we discretize the electric field integral equations into the matrix form and select sinusoidal functions as basis functions. We verify the validity of numerical results and compare the results with existing ones in showing a good agreement between them. When the dielectric cover thickness is varied, the resonant frequencies and input impedances in the variation of air gap, patch length and thickness and permittivity of superstrate are presented and analyzed.

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EXTENDED DRY STORAGE OF USED NUCLEAR FUEL: TECHNICAL ISSUES: A USA PERSPECTIVE

  • Mcconnell, Paul;Hanson, Brady;Lee, Moo;Sorenson, Ken
    • Nuclear Engineering and Technology
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    • v.43 no.5
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    • pp.405-412
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    • 2011
  • Used nuclear fuel will likely be stored dry for extended periods of time in the USA. Until a final disposition pathway is chosen, the storage periods will almost definitely be longer than were originally intended. The ability of the important-tosafety structures, systems, and components (SSCs) to continue to meet storage and transport safety functions over extended times must be determined. It must be assured that there is no significant degradation of the fuel or dry cask storage systems. Also, it is projected that the maximum discharge burnups of the used nuclear fuel will increase. Thus, it is necessary to obtain data on high burnup fuel to demonstrate that the used nuclear fuel remains intact after extended storage. An evaluation was performed to determine the conditions that may lead to failure of dry storage SSCs. This paper documents the initial technical gap analysis performed to identify data and modeling needs to develop the desired technical bases to ensure the safety functions of dry stored fuel.

Pedestrian Distribution in High-Rise Commercial Complexes: An Analysis of Integrating Spatial and Functional Factors

  • Xu, Leiqing;Xia, Zhengwei
    • International Journal of High-Rise Buildings
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    • v.5 no.2
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    • pp.95-103
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    • 2016
  • One of the key problems in the design of high-rise commercial complex is how to guide reasonable pedestrian distribution in commercial space. In this study, pedestrian distribution in three high-rise commercial complexes in Shanghai and Hong Kong was studied using spatial configuration analysis software Space Syntax and quantification of physical elements in commercial spaces, such as functional attractiveness, entrances, escalators, level variations and passage width. Additionally, in an attempt to integrate functions with spatial integration and spatial depth, two combination variables, the spatial coefficient of function (IF) and spatial depth coefficient of function (F/D), were proposed. The results of the correlation analysis and multiple regression analyses reflected the following: (1) Regarding the influence on pedestrian distribution, there was a synergistic and complementary relationship between function and space; (2) The comprehensive flow distribution analytic model could successfully interpret flow distribution in high-rise commercial complexes and its R Square ranged up to about 70% in the three cases; (3) The spatial coefficient of function (IF) and spatial depth coefficient (F/D) could effectively integrate functions and spatial configuration, which could help close the gap between over-emphasis on function in commercial research and the lack of consideration of function in space-syntax analysis.

Spectral Domain Analysis of Resonant Frequency in Rectangular Microstrip Patch Antenna on Uniaxial Substrates with Airgap and Superstrate (공기 갭과 덮개층을 갖는 이방성 매질 위의 사각 마이크로스트립 패치 안테나 공진 주파수의 파수 영역 해석)

  • Lee, Sang-Mok;Yoon, Joong-Han;Kim, Heung-Soo
    • Journal of IKEEE
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    • v.5 no.1 s.8
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    • pp.91-99
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    • 2001
  • Spectral domain of resonant frequency rectangular microstrip patch antenna on anisotropic substrates and superstrate with airgap are analyzed. First, we derive dyadic Green function for selected anisotropic material by constitutive relation and then formulate integral equations of electric fields using Fourier transform in space region. Using Galerkin's moment method, we discretize the electric field integral equations Into the matrix form and select sinusoidal functions as basis functions. We verify the validity of numerical results and compare the results with existing ones in showing a good agreement between them. The resonant frequencies in the variation of air gap, patch length and permittivity of superstrate anisotrpy ratio of anisotrpic superstrate are presented and analyzed.

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A Study on the Interior Conditions of Public Libraries and Satisfaction of User (공공도서관의 실내현황 및 사용자 만족도에 관한 연구)

  • Chang, A-Ri;Son, Yeo-Rym;Hwang, Yeon-Sook
    • Korean Institute of Interior Design Journal
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    • v.17 no.4
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    • pp.75-83
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    • 2008
  • This study examined the various functions of public libraries, as well as user satisfaction and needs. We targeted 6 public libraries in the Seoul and Gyunggi area. After 280 library users were surveyed, the collected data were analyzed with an SPSS for Win 14.0 statistics program, where we used frequency, percentage, mean, T-test, One-way ANOVA, and Duncan's test. The major findings were as follows: 1) Half of the users used educational functional space, mainly in the 10-20 age group, who used it for educational purposes as a student or to prepare for getting a job. 2) There were gaps between the furniture arrangement and user preference since most libraries used a rigid system while users preferred a more flexible arrangement. 3) Space by space, public library satisfaction levels differed according to the users' gender and age. Satisfaction of the digital information room scored high, especially for users in their forties. Since public library users are diverse and require various functions, library interiors should be planned accordingly in terms of furniture arrangement and interior design. In particular, there was a gap between satisfaction by age groups, so libraries must account for community needs by considering the age group demographics of their surrounding areas.

The adverse impact of personal protective equipment on firefighters' cognitive functioning

  • Park, Juyeon
    • The Research Journal of the Costume Culture
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    • v.27 no.1
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    • pp.1-10
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    • 2019
  • Firefighters wear Personal Protective Equipment (PPE) for protection from environmental hazards. However, due to the layers of protective functions, the PPE inevitably adds excessive weight, bulkiness, and thermal stress to firefighters. This study investigated the adverse impact of wearing PPE as an occupational stressor on the firefighter's cognitive functioning. Twenty-three firefighters who had been involved in firefighting at least for 1 year were recruited. The overall changing trend in the firefighter's cognitive functioning (short-term memory, long-term memory, and inductive reasoning) was measured by the scores of three standardized cognitive tests at the baseline and the follow-up, after participating in a moderate-intensity physical activity, wearing a full ensemble of the PPE. The study findings evinced the negative impact of the PPE on the firefighter's cognitive functioning, especially in short-term memory and inductive reasoning. No significant influence was found on the firefighter's long-term memory. The results were consistent when the participant's age and BMI were controlled. The outcomes of the present study will not only fill the gap in the literature, but also provide critical justification to stakeholders, including governments, policymakers, academic communities, and industry, for such efforts to improve human factors of the firefighter's PPE by realizing the negative consequences of the added layers and protective functions on their occupational safety. Study limitations and future directions were also discussed.

정보전달 매체로서의 과학저어널의 문제점과 그 개선책

  • 이영자
    • Journal of Korean Library and Information Science Society
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    • v.6
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    • pp.159-185
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    • 1979
  • The dissemination of scientific information in Society involves interactions among a number of publics and many kinds of information channels. There is a need for examining the the entire process of information dissemination for the solving many problems which scientific many problems which scientific communication is now confronted with, This paper is an attempt to identify the functions of a scientific journal as one of major inf. transfer media, to clarify the problems in performing the functions, and to synthesize various on-going efforts toward the improvement and solution of such problems. Some conclusions derived from this study are as follows; (1) a scientific journal was, is and will be the valuable primary source for the recording and controlling scientific in formation which plays a role as a main energy source in the scientific activities. (2) Traditional built-in delays involved in the communication by a scientific journal should be improved by way of some new methods and techniques such as, of establishing a publishing center, controlling vocabularies in the scientific papers, distributing pre-publication materials, etc. (3) There should be a organized special committe for scientific communication for the assuming the responsibilities of educating, planning and carrying out activities relating to scientific information. (4) To improve the function of a scientific journal as information transfer media, other informal primary media such as report, preprint, etc, and secondary media such as abstracts and indexes should be studied which will result in the clarification of unigue functions, and advantages and disadvantages of each media. as an information dissemination media. (5) Each government should pay attention to the national information system as a changing social system and should recognize the gap in speed between technological development and the change of a social system Technological development should be made a contribution to the improvement of social system.

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A Minor Transactivation Effect of GATA-3 on its Target Sites in the Extrachromosomal Status

  • Lee, Gap-Ryol
    • Journal of Microbiology and Biotechnology
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    • v.17 no.12
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    • pp.2056-2060
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    • 2007
  • Transcription factor GATA-3 is the critical transcription factor for Th2 cell differentiation. In spite of its importance in Th2 cell differentiation, the molecular mechanism for its action in Th2 differentiation is poorly understood. Previous studies have suggested that GATA-3 may be involved in the chromatin remodeling in the Th2 cytokine locus. To determine whether GATA-3 exerts its effect on its target sites in the extrachromosomal status, cell transfection assay was performed. In this assay, 800 bp IL4 promoter-luciferase constructs linked with GATA-3 target sites were transfected into the M12 B cell line, D10 mouse Th2 cell lines, and human T lymphoma Jurkat cell lines with or without the GATA-3 expression vector. The GATA-3 effects on its target sites were minimal in the extrachromosomal status, supporting the previous propositions that GATA-3 functions at the chromatin level by remodeling chromatin structure.