• Title/Summary/Keyword: method of ideal elements

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Implementation of SNR Estimator for ISDB-T Systems (ISDB-T 시스템을 위한 SNR 추정기 구현)

  • Kim, Seongihl;Sohn, Chae-Bong
    • Journal of Broadcast Engineering
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    • v.18 no.6
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    • pp.927-934
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    • 2013
  • This paper aims to realize a Signal to Noise Ratio Estimator which constitutes a critical index of the broadcasting system in OFDM system with a synchronized type based on ISDB-T system. Of the elements which are comprising OFDM segments of ISDB-T system using the MSE algorithm suitable for ASIC design owing to its low complexity among a diverse SNR estimation methods, SNR estimation method using the broadcasting information data and the SNR estimation method using scattered pilot signal were realized by RTL. These two methods were compared in terms of their performance through simulation test not only in the AWGN channel which is an ideal channel, but also in SFN channel and frequency selective fading channel, which are distorted channels. Complexity of two methods were also compared through RTL realization. As a result of this comparison analysis, it was concluded that the SNR estimation method using scattered pilot signal shows more excellent performance and easiness in realization.

A Study on the Expressional characteristics of Geometrical Design in the Deconstructive and Experimental Architects (해체 및 실험적 건축가들의 기하학적 디자인 표현 특성에 관한 연구)

  • 황태주
    • Korean Institute of Interior Design Journal
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    • no.11
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    • pp.57-63
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    • 1997
  • In the early 20'c, scientific thoughts make a change the absolute and separate concept of space-time into relative concept of continual entity; a kind of ideal world. It suggests that the meaning of geometry as absolute truth with which has endowed human beings would changed to a relative meaning of accumulation in intellectual work on 'nature'. This cognitive changes appeared into absolute arts in 20'c like Cubism, Superematism or Constructivism. De Stijl movement which had recepted the relative concepts like Einstein's 'theory of relativity' as a developed thought from Newton-Cartesian cognition on the world. Abstration would be adequate method for expressing the dynamics and interrelationship between forms and for giving values to indivisual elements in a compositiov. This method had appeared Modern architectural form, as a common framework. The expression characteristics of geometrical design in Deconstructive and Experimental architecture were summerized in four features through the results of the analysis. First, the relation of architectural element and intertextuality is expressed in discontinuation of context and refusal of functional building. Second, the concept of trace expresses as connection of place, decomposing of excavation of trace, trace of axis, trace of fragments. Third, anti-gravity expression is there to express of open cubic, to outgrow of rectangular system, to outgrow of volume, to separate of ground connectiov. Fourth, the complex composition of abstracted geometric form is these to abstracted geometry about indefinite shape, to layer through the overlap and collage, to de-meaning and amusement of form through the pursuit of uncertainty, to indeterminate of formal meaning through operation and composition of similar form cause to the diverse of meaning.

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Dual Band Design of Aperture-Coupled Cavity-Fed Microstrip Antenna (이중 대역 개구면 결합 공진기 급전 마이크로스트립 안테나 설계)

  • Jang, Guk-Hyun;Nam, Kyung-Min;Lee, Jang-Hwan;Nam, Sang-Ho;Kim, Chul-Un;Kim, Jeong-Phill
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.3 s.357
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    • pp.26-32
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    • 2007
  • A simple but accurate equivalent circuit of an aperture-coupled cavity-fed microstrip patch antenna is developed. It consists of ideal transformers, admittance elements, and transmission lines, and the related circuit element values are computed by applying the reciprocity theorem and complex power concept with the spectral-domain immittance approach. After validating by the published design example, a dual-band antenna was designed with the help of a hybrid optimization method. For this purpose, the Genetic Algorithm is applied with the Nelder-Mead simplex method. The obtained good results show that this approach turned out to be a very efficient tool for the design of aperture-coupled cavity-fed microstrip patch antenna having various structural design parameters.

Shape Optimal Design by P-version of Finite Element Method (p-Version 유한요소법에 의한 형상 최적화설계)

  • Kim, Haeng Joon;Woo, Kwang Sung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.4
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    • pp.729-740
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    • 1994
  • In the shape optimal design based on h-version of FEM, the ideal mesh for the initial geometry most probably will not be suitable for the final analysis. Thus, it is necessary to remesh the geometry of the model at each stage of optimization. However, the p-version of FEM appears to be a very attractive alternative for use in shape optimization. The main advantages are as follows; firstly, the elements are not sensitive to distortion for interpolation polynomials of order $p{\geq}3$; secondly, even singular problems can be solved more efficiently with p-version than with the h-version by proper mesh design; thirdly, the initial mesh design are identical. The 2-D p-version model for shape optimization is presented on the basis of Bezier's curve fitting, gradient projection method, and integrals of Legendre polynomials. The numerical results are performed by p-version software RASNA.

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Inquisitive Tendency Comparative Analysis on the 'Education with Robots' Units in the 2015 Revised Practical Arts Textbook (2015 개정 실과 교과서 '로봇 활용 교육' 단원 탐구성 비교 분석)

  • Lee, Jeaho;Gen, Sang-il
    • Journal of Creative Information Culture
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    • v.7 no.1
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    • pp.21-29
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    • 2021
  • This paper analyzed 'Education with Robots' of the Practical Arts unit among the six textbooks developed under the 2015 revised curriculum, and provided implications for selection of textbooks, researching curriculum, and developing the next textbook. As a result of analyzing the prior study, it was found that the inquiry analysis was insufficient in the elementary school 'Education with Robots' unit. On the contrary, in the middle and high school textbooks research were sufficient. Therefore, we analyzed the contents of the textbook using the Romey analysis method, judging that our children who will live in the era of the Fourth Industrial Revolution need an inquiry type textbook. As a result of analyzing textbooks, there was no ideal textbook with an inquisitive disposition in all analysis elements, and in all textbooks, the analysis element with the lowest inquiry disposition was the text, and the highest analysis element was activity.

A Study Based on Quantifying Theory for a Non-fiction Creation Tool : Focus on Comparative Analysis of and (정량화 이론을 활용한 논픽션 창작도구 모델 연구 : <소트 오피스> 및 <스토리헬퍼> 비교분석 중심으로)

  • Lyou, Chul-gyun;Park, Eun-kyung
    • The Journal of the Korea Contents Association
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    • v.16 no.3
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    • pp.247-256
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    • 2016
  • This paper points out that the existing digital story creation tools are biased in the field of entertainment storytelling, so it proposes a specialized tool for non-fiction creation. This paper selects Quantifying Theory to design this tool. When creating nonfiction storyline, it is important to have the appropriate combination between the actual events and fictional elements. A Gossip System, based on Quantifying Theory, is suitable for that work. Before designing a Gossip System as a nonfiction creation tool, this analysis evaluated that the Gossip System in and . As a result, the linked structure in is useful in searching for material for non-fiction creation, and the separated structure in is ideal for arranging dramatic events. This paper proposed a method of switching the fact to fiction through a combination of this two Gossip System structure. I conclude that this is the best method for non-fiction creation tool.

Analysis of Steady Flow by Main Pipe Arrangement in the Water Distributing Pipe Network (배수관망(配水管網)의 간선배치(幹線配置)에 따른 정류(定流)흐름 해석(解析))

  • Lee, Jeung Seok;Park, Ro Sam;Kim, Jee Hak;Choi, Yun Young;Ahn, Seung Seop
    • Journal of Korean Society of Water and Wastewater
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    • v.13 no.3
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    • pp.73-82
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    • 1999
  • In this study, the optimal analysis for pipe network is performed for the combined ideal pipe network system(CASE 1, CASE 2 and CASE 3) which is composed of 25 nodes, 41 elements, and 1 fixed nodal head with evaluating pressure variation distribution of main and branch in grid composed drainage pipe network. The linear analysis technique used as the analysis method in this study, the KYPIPE being used extensively as the linear technique to design and analysis of pipe network is applied. Firstly, in the analysis of pipe network, the CASE 2 and CASE 3 supply same thing(value) in the result of considering the total flow provided each pipeline, but in the general intension in the case of CASE 2, relative width of supply is more large than CASE 1 and CASE 3. Secondly, in the analysis technique of pipe network, CASE 3 is analysed largest as a result of comparing with same heads, and in the order of their size CASE 2 and CASE 1 were determined but the difference doesn't appear to be obvious. Thirdly, as the result of determining main factor, pressure in the design and analysis of net work. CASE 3 is from Node 3 to 25 than CASE 1 and CASE 2 and it is determined in the order of their size, CASE 2 and CASE 1. Finally, in this study, discharge flow distribution is evaluated in the same condition with 3-type CASE in the case of branch position for designing optimal composed drainage pipe network. As the result of that, branch pipe perform. Therefore, it is thought that the efficient and reasonable management of water supply and sewerage design will be possible if it give all our energies to study at the pipe system design in and out of country in the future.

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Microstructure and Mechanical Properties of High Strength and Stretch-Flangeability Hot-Rolled Steels (고강도-신장플랜지성 열연강의 미세조직 및 기계적 성질)

  • Chun, Eun-Joon;Lee, Ju-Seung;Do, Hyeong-Hyeop;Kim, Seong-Ju;Park, Yong-Ho;Kang, Nam-Hyun
    • Korean Journal of Materials Research
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    • v.22 no.1
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    • pp.16-23
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    • 2012
  • Research into the development of high strength (1 GPa) and superior formability, such as total elongation (10%), and stretch-flangeability (50%) in hot-rolled steel was conducted with a thermomechanically controlled hot-rolling process. To improve the overall mechanical properties simultaneously, low-carbon steel using precipitation hardening of Ti-Nb-V multimicroalloying elements was employed. And, ideal microstructural characteristics for the realization of balanced mechanical properties were determined using SEM, EBSD, and TEM analyses. The developed steel, 0.06C-2.0Mn-0.5Cr-0.2(Ti + Nb + V), consisted of ferrite as the matrix phase and second phase of granular bainite with fine carbides (20-50 nm) in both phases. The significant factor of the microstructural characteristics that affect stretch-flangeability was found to be the microstructural homogeneity. The microstructural homogeneity, manifest in such characteristics as low localization of plastic strain and internally stored energy, was identified by grain average misorientation method, analyzed by electron backscattered diffraction (EBSD) and hardness deviation between the phases. In summar, a hot-rolled steel having a composition 0.06C-2.0Mn-0.5Cr-0.2(Ti + Nb + V) demonstrated a tensile strength of 998 MPa, a total elongation of 19%, and a hole expansion ratio of 65%. The most important factors to satisfy the mechanical property were the presence of fine carbides and the microstructural homogeneity, which provided low hardness deviation between the phases.

Compensation of Radiation Pattern Distortion by Mutual Coupling in the Array Antenna Using the Particle Swarm Optimization Algorithm (입자군집 최적화 알고리즘을 이용한 배열안테나의 상호결합에 의한 방사패턴 왜곡보상)

  • Kim, Jae Hee;Ahn, Chi-Hyung;Chun, Joong-Chang
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.5
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    • pp.458-464
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    • 2016
  • This paper proposes the compensation method which decreases the radiation pattern distortion caused by the mutual coupling in an array antenna. If the element distance of an array antenna decreases, the radiation pattern could be distorted by the strong mutual coupling, which changes the magnitude and phase of input signals and causes an unwanted radiation pattern. To remove the pattern distortion, compensated input signals are inserted in an array antenna. The magnitude and phase of input signals are determined by Particle Swarm Optimization (PSO) algorithm. A $4{\times}1$ dipole array antenna with omnidirectional elements is used to confirm the validity of the algorithm, where each element is placed in 0.2 wavelength to evoke the strong coupling. After input signals are optimized by PSO, it is found that the compensated radiation results in the same as the ideal case.

A Study on Accreditation-based Qualification System: Focusing on the Case of K University (인증평가형 자격제도에 관한 연구: K 대학 사례를 중심으로)

  • Yong-Yeon Cho;Seung-Chan Kang
    • Journal of Practical Engineering Education
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    • v.15 no.3
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    • pp.739-750
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    • 2023
  • Several preceding studies have been conducted to integrate the education programs and qualification examination systems in higher education institutions, such as four-year engineering colleges and vocational universities. However, in practice, the implementation of such integration is a rare occurrence. The most ideal method of integrating education and qualifications can be seen as the unified operation of educational programs and qualification assessments. However, various elements required for accreditation of educational institutions and qualification systems must precede this. In this paper, we first compare and analyze the currently implemented competency-based qualification system and the Accreditation for engineering education evaluation operating as a quality management system for educational programs. Subsequently, through a case study of University K, which concurrently operates the Accreditation for engineering education and competency-based qualification systems, we examine the potential linkage between education and qualifications. After reviewing the case that education and qualifications can be linked, and reflecting the analysis results, if a program that has obtained the Accreditation for engineering education operates a curriculum that satisfies the criteria for Course-based Qualification System. We propose Accreditation-based Qualification System that can grant qualifications, students who have completed it will be provided.