• Title/Summary/Keyword: Comparative Characteristics

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Analytical solution of free vibration of FG beam utilizing different types of beam theories: A comparative study

  • AlSaid-Alwan, Hiyam Hazim Saeed;Avcar, Mehmet
    • Computers and Concrete
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    • 제26권3호
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    • pp.285-292
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    • 2020
  • In engineering structures, to having the projected structure to serve all the engineering purposes, the theory to be used during the modeling stage is also of great importance. In the present work, an analytical solution of the free vibration of the beam composed of functionally graded materials (FGMs) is presented utilizing different beam theories. The comparison of supposed beam theory for free vibration of functionally graded (FG) beam is examined. For this aim, Euler-Bernoulli, Rayleigh, Shear, and Timoshenko beam theories are employed. The functionally graded material properties are assumed to vary continuously through the thickness direction of the beam with respect to the volume fraction of constituents. The governing equations of free vibration of FG beams are derived in the frameworks of four beam theories. Resulting equations are solved versus simply supported boundary conditions, analytically. To verify the results, comparisons are carried out with the available results. Parametrical studies are performed for discussing the effects of supposed beam theory, the variation of beam characteristics, and FGM properties on the free vibration of beams. In conclusion, it is found that the interaction between FGM properties and the supposed beam theory is of significance in terms of free vibration of the beams and that different beam theories need to be used depending on the characteristics of the beam in question.

필라멘트 와인딩과 인발성헝 제작 복합소재 교량 바닥판의 휨 특성 비교분석 (Comparative Study on the Flexural Characteristics of Composite Bridge Deck Fabricated with Filament Winding and Pultrusion)

  • 이성우
    • 한국전산구조공학회논문집
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    • 제18권2호
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    • pp.191-200
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    • 2005
  • 본 논문에서는 유리섬유 복합소재 교랑 바닥판 개발에 필요한 기초 자료를 마련하기 위하여, 필라멘트 와인딩공정과 인발성형공정으로 제작된 복합소재 교량 바닥판에 대해 휨시험과 구조해석을 실시하여, 휨특성을 비교$\cdot$분석하였다. 필라멘트 와인딩으로 제작된 삼각형 형상의 복합소재 교량 바닥판의 성능을 비교하기 위하여, 미국 MMC사의 Duraspan 바닥판과 동일한 크기의 바닥판 시험체를 필라멘트 와인딩으로 제작하여 휨시험을 실시하고 최대 파괴하중과 처짐, 변형률을 비교하였으며, 필라멘트 와인딩 바닥판 시험체와 동일한 바닥판 모델에 대해 구조해석을 실시하여 시험한 결과와 비교하였다.

2000년대 패션에 표현된 미니멀리즘과 맥시멀리즘의 비교 미학적 연구 (A Comparative Study on Minimalism and Maximalism in the 2000s Fashion)

  • 박은경
    • 복식
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    • 제62권8호
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    • pp.100-117
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    • 2012
  • This research aims to study comparatively on the aesthetic characteristics of minimalism and maximalism in the 2000s fashion, based on the previous studies in art and design. For this purpose, literature survey and demonstrative analysis of fashion collection photographs were performed. The scope of this research is from 2000 to 2010. The results are as follows: First, the formativeness of minimalism fashion in the 2000s is analyzed as understatement, simplicity, non decorativeness. The internal meanings are reduction, purity, asceticism, transcendence and practicality. Second, the formativeness of maximalism fashion in the 2000s is analyzed as enlargement, fusion, decorativeness, luxury and avant-garde. The internal meanings are pluralism, open mind, sensibility, fun and materialism. Third, minimalism and maximalism fashion in the 2000s are opposite when compared to each other. While minimalism pursues the nature of human being by ascetic approach, maximalism does it by immersing in human affairs. Within the spectrum of these two opposing ends, there are different degrees of expressions. Also these two trends fuse with other styles. As these trends express and pursue the nature of human being, they are expected to exist incessantly in the future.

폐기물 처리시설 입지선정의 효율화 방안에 관한 연구 - 여주군 폐기물 매립지 입지선정 사례를 중심으로 - (A Case Study on Simplified Assessment Method for Site Selection of the Waste Treatment Facilities in Korea)

  • 이무춘;구자건;김기철;권연정
    • 환경영향평가
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    • 제8권1호
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    • pp.71-79
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    • 1999
  • The comparative evaluation is the most effective method for site selection because the selection of waste treatment facility is to determine the optimum site out of limited candidate sites. This study adopted the ordinal scale evaluation, one of methods of comparative evaluation. The ordinal scale evaluation aims to determine the investigating items referring to the character of sites, to determine the importance factors for investigating items, and to determine the optimum site according to the quantitative evaluation. As a result of this study, the defects of the former reports on the environmental characteristics, such as obscurity of meaning and subjective statement, were reduced by the ordinal scale evaluation which is one of the quantitative evaluation methods. This ordinal scale evaluation method has some valuable advantages, such as, to be able to consider the cost-effect efficiency, to consider the objectiveness and the clearness of the reports on the environmental characteristics. Therefore the reducement of social complications about site selection of the indisposed facilities could be expected by this study.

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대화면/고화질 TFT-LCD 개발을 위하여 ELA 및 SMC로 제작된 다결정 실리콘 박막 트랜지스터의 화소 특성 비교 (Comparative Pixel Characteristics of ELA and SMC poly-Si TETs for the Development of Wide-Area/High-Quality TFT-LCD)

    • 한국진공학회지
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    • 제10권1호
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    • pp.72-80
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    • 2001
  • 본 논문에서는 ELA(excimer laser annealing) 및 SMC(silicide mediated crystallization) 공정으로 제작된 다결정 실리콘 TFT-LCD(Thin Film Transistor-Liquid Crystal Display) 화소의 전기적 특성을 Spice회로 시뮬레이션을 통해 비교 분석하였다. 복잡한 TFT-LCD 어레이 (array) 회로의 전기적 특성 분석을 위하여 GUI(Graphic User Interface) 방식으로 손쉽게 복잡한 회로를 구성할 수 있는 PSpice에 AIM-Spice의 다결정 실리콘 박막 트랜지스터 소자 모델을 이식하고, AIM-Spice의 변수 추출법을 개선 체계화하였으며 ELA 및 SMC공정으로 각기 제작된 다결정 실리콘 박막트랜지스터에 적용하여 단위 화소 및 라인 RC 지연을 고려한 화소 특성을 비교 분석하였다. 비교 결과 ELA 다결정 실리콘 박막 트랜지스터 소자가 SMC에 비해 TFT-LCD의 화소 충전 시간 및 킥백(kickback) 전압 특성이 모두 우수하게 나타남을 확인하였다.

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Structural Characteristics that Influence on the Insecticidal Activity of 2-(n-Octyl)pseudothiourea Analogues against the Diamondback Moth (Plutella xylostella, L.)

  • Soung, Min-Gyu;Kil, Mun-Jae;Sung, Nack-Do
    • Bulletin of the Korean Chemical Society
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    • 제30권11호
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    • pp.2749-2753
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    • 2009
  • Structural characteristics that influence on the insecticidal activity ($pI_{50}$) of 2-(n-octyl)isothiourea analogues (1-45) against the diamondback moth (Plutella xylostella, L.) based on three dimensional quantitative structure activity relationships (3D-QSARs) were discussed quantitatively using a comparative molecular field analysis (CoMFA) and a comparative molecular similarity indeces analysis (CoMSIA) methods. The statistical values of the CoMFA 2 model were better than those of the CoMSIA 1 model. The CoMFA 2 model was the optimized model with the correlativity (the training set: Ave. = 0.104 & PRESS = 0.613) and the predictability (the test set: Ave. = 0.086 & PRESS = 0.096). Insecticidal activities with the optimized CoMFA 2 model were dependent upon steric factors (79.4%) of $R_1-R_3$ substituents. From the analytical results of CoMFA contour maps, it is predicted that the R1 substituent of 1-45 which has a steric favor in a broad space, $R_2\;and\;R_3$ groups with a steric favor in a narrow space and a H-bond donor favor would have better the insecticidal activity.

산불피해지역에서 숲 가꾸기 실행유무가 산불에 미치는 영향 (Comparative analysis of forest fire danger rating on the forest characteristics of thinning area and non-thinning area on forest fire burnt area)

  • 이시영;이명욱;염찬호;권춘근
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2008년도 정기총회 및 학술발표대회
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    • pp.153-156
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    • 2008
  • Comparative analysis of forest fire danger rating on the forest characteristics of thinning area and non-thinning area on forest fire burnt area was studied in this work. To investigate the effect of thinning slash in forest fire, Gangneung-si Wangsan-myeon, Ulgin-gun Wonnam-Myeon, Samchok-si Gagok-Myeon, in which forest fire broke out, were selected. As a result that investigated forest fire danger ratio between thinning slash and non-thinning slash, leeward scorching ratio(36%), crown damage ratio(29%), mortality of branch at the former are higher than those at the latter, leeward scorching ratio of tree, where thinning slash is around, is 10%-20% higher than that of independent tree. So I estimate that thinning slash has a some effect on the intensity of forest fire. And the result to investigate damage of forest fire according to tree species shows that leeward scorching ratio of conifer is 5% higher than that of non-conifer, and mortality of branch of the former is 19% higher than that of the latter. It is considered that forest fire may affect directly to a tree trunk if it diffuse to piled thinning tree because there was no space between thinning trees and trees. Furthermore, it was found that re-ignition had a chance to occur due to lots of piled thinning trees.

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환자 보호자 만족도 조사에 대한 신뢰도 및 타당성 연구 - Korean Medicine Satisfaction Questionnaire(KMSQ)를 도입하여 - (A Study of Validity and Reliability about Parent's Satisfaction in Korean Medicine Hospital - Introducing Korean Medicine Satisfaction Questionnaire -)

  • 정상교;김기봉
    • 대한한방소아과학회지
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    • 제27권2호
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    • pp.31-47
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    • 2013
  • Objectives This study was done to confirm reliability, validity and the internal structure of the Korean Medicine Satisfaction Questionnaire(KMSQ). Methods 154 parents who visited in Department of Pediatrics of Korean Medicine, University Hospital participated in this study. They were statistically analyzed by using PASW Statistics 20.0K for Windows. Results Factor analyses were largely divided into six categories such as Hospital, Waiting & Consultation Time, Doctor, Medicine, Therapy, and Cost. The validity and reliability of KMSQ were favorable. The highest average score of satisfaction was Doctor category as $4.20{\pm}0.51$ and the lowest one was Cost as $3.33{\pm}0.71$. The six factors showed highly positive relationship from correlation analysis. The result of comparative study on parent's demographic characteristics showed only one significant difference in satisfaction of Doctor within occupation. The result of comparative study on child's demographic characteristics showed significantly different in satisfaction of Therapy within gender, and of Medicine within age. Every average score of satisfaction showed somewhat difference within each section, and only 5.6% of them showed significantly difference in T-test. Conclusions Uses and research with the KMSQ as subjective tool in various department or medical institution are suggested.

국내외 재난대응 이동형 병원의 배치특성 비교분석 연구 (A Comparative Study on the Deployment Characteristics of Korean and Foreign Mobile Hospitals Responding to Disasters)

  • 양민규;서상욱;이영
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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    • 제25권1호
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    • pp.29-40
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    • 2019
  • Purpose: The purpose of this study is to analyze the deployment characteristics of korean and foreign mobile hospitals and to draw out the advantages and disadvantages based on the movement of patients. Methods: The arrangement and user movement lines of foreign mobile hospitals which were actually utilized, and the arrangements and user movement lines of korean mobile hospitals are compared and analyzed. Based on the results of the comparative analysis, we suggest the optimal placement of mobile hospital in Korea. Results: The recently developed Korean mobile hospitals have made many improvements. However, there is no practical use case for the mobile hospital in Korea, so it is necessary to establish the basis for the mobile hospital development site and the site access considerations. In addition, there is no detailed analysis of the movement of the administrators other than the medical staff, and it is considered that research on safe waste disposal is further needed. Implications: It is highly likely to be used as a basic data to find out the combination method of mobile hospitals that can efficiently deal with disasters through the arrangement and movement analysis of mobile hospitals in Korea and abroad.

Comparative Analysis of Historical National Image Advertising in Korea - Video Advertisements Produced between 1998-2017

  • Bae, Inkyung
    • International Journal of Contents
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    • 제16권4호
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    • pp.84-97
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    • 2020
  • Since national image video advertisements are a means of public relations with wide delivery and major repercussions at home and abroad, this study performs a comparative analysis of video advertisements aired by previous governments as reported by Daejung Kim, Moohyun Roh, Myungbak Lee, and Geunhye Park. The characteristics of the previous governments, whether or not social trends were reflected, and the importance of traditional and modern elements were examined. As we describe, there are clear differences in video advertisements by government regime, and while messages expressing traditional values of Eastern culture have gradually decreased, reflecting the trends of the times, the messages emphasizing the modern values of the West have gradually increased. Our research confirmed that traditional elements such as 'Samulnori' and 'Taekwondo' are gradually disappearing. In addition, it was confirmed that the collective values, traditional values, and humanism represented by the 'large crowd' and 'traditional elements' in the Kim Dae-jung and Roh Moo-hyun administration changed in the Lee Myung-bak and Park Geun-hye administrations to more individualistic, materialistic, Western values. This study is meaningful in that it analyzed the components and characteristics of national image advertisements by governments in the past, how social trends were reflected, and the weight difference between traditional and modern elements. Based on this research, the significance of the current Moon Jae-in government's groundwork for follow-up research should not be understated.