• Title/Summary/Keyword: Round

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Biaxial Compressive Deformation Characteristics of Double Round Copper Pipes (2중 원형동관의 2축압축 변형특성에 관한 연구)

  • Yoo, C.K.;Won, S.T.
    • Transactions of Materials Processing
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    • v.23 no.1
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    • pp.35-40
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    • 2014
  • The deformation characteristics of a double round copper pipe and a single round copper pipe under biaxial compression were studied using a horizontal compression die. The change in punch load and in deformation behavior was measured during the experiments using various compressive deformation rates in the range of 10mm/min. ~ 450mm/min. The maximum punch load for both the double round copper pipe and the single round copper pipe decreased with increasing compressive deformation rate. The maximum punch load for the single round copper pipe was twice that of the double round copper pipe. After a 4.0mm stroke, the deformed shape of the single round copper pipe remained rectangular. However the outer tube of double round copper pipe remained rectangular while the inner tube was clover shaped. The stress and strain distributions in the double round copper pipe and the single round copper pipe show clear differences. The results of numerical simulations using Deform-2D are in good agreement with experimental results.

Round Atelectasis - One case report - (Round Atelectasis 수술치험 1예 보고)

  • 유영종
    • Journal of Chest Surgery
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    • v.22 no.5
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    • pp.857-861
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    • 1989
  • Round atelectasis is an uncommon benign pulmonary condition not relevant to neoplastic or inflammatory lung disease, usually presenting as a peripheral parenchymal round mass density on a chest roentgenogram. Recently, authors experienced one patient with this disease entity associated with spontaneous pneumothorax who was treated surgically with a successful outcome. The case is thought to be the first documented report of round atelectasis in Korea.

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A Proposal of Round Specimen for the Determination of Crack Arrest Toughness (균열정지 인성치결정을 위한 원형시편의 제안)

  • 이억섭;김상철;송정일;이규철
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.5
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    • pp.1472-1478
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    • 1991
  • 본 연구에서는 Rectangular Computer Tension(CT) 시편을 수정하여 만든 표준 시편인 MRL-CLWL시편(material research laboratorycrack line wedge loaded specimen )으로 균열정지 인성치를 결정하였다. 그리고 CT시편과 같은 효과를 갖는 Newman등 이 제안한 round compact tension(RCT)시편을 수정한 Round-CLWL 시편으로 균열정지인 성치를 결정하여 상호 비교평가하였다. Round-CLWL 시편은 시편제작시 round-bar를 절단하여 시편으로 가공할 수 있으므로 가공성이 좋으며 따라서 가공비가 적게 든다. 특히 균열 위치 및 방향을 임의로 선택하여 가공하기가 용이하므로 방향성이 있는 소 재의 균열정지 인성치를 결정하는 데 매우 편리한 시편이라 생각된다. 본 논문에서 는 Round-CLWL 시편으로 $K_{1a}$ 값을 계산하는데 필요한 형상계수를 결정하였으며, Polymethylmethacrylate(PMMA)를 사용하여 Round-CLWL 시편 채택의 타당성 확인을 위 한 MRL-CLWL과 Round-CLWL 시편 채택의 타당성 확인을 위한 MRL-CLWL과 Round-CLWL시 편의 $K_{1a}$결정 실험을 하였다.하였다.

Evaluation of Static/Dynamic Structural Strength for Automotive Round Recliner (자동차용 라운드 리클라이너 정적/동적 구조 강도 평가)

  • Lee Dongjae;Park Changsoo;Lee Kyoungteak;Kim Sangbum;Kim Heonyoung
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.1
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    • pp.140-146
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    • 2005
  • This study presents the development of a round recliner using the finite element method. That reduces the number of test repeating times and gives an information about stiffness. A simulation model of round recliner mounting seat module and tooth strength simulation are established using a PAM-CRASH and ABAQUS. With the optimization of gear profile, structural strength design of round recliner was achieved. The round recliner seat module simulation, structure strength simulation and a crash safety are requested by FMVSS test. Solution of round recliner optimum variable study and design problem are searched for round recliner stress, deformation and application. Also an examination of safety is made.

Development of Educational Materials for Prevention of Accidents in Vocational High Schools (특성화고등학교 현장실습 사고와 건강문제 예방을 위한 교육자료 개발 및 적용)

  • Choi, Eun-Hi;Lee, Mi-Kyoung;Hong, Jin Eui;Jung, Hye-Sun
    • Journal of the Korean Society of School Health
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    • v.33 no.3
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    • pp.194-202
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    • 2020
  • Purpose: The purpose of the study was to develop educational materials on field practice safety based on existing field practice data and accident cases regarding vocational high schools and apply them to identify their impact. Methods: The existing data, accumulated since 2010, on field practices of vocational high schools were analyzed, and educational materials regarding field practices were developed by six experts. 195 students in three vocational high schools were surveyed before and after being taught with the materials. The survey asked about their knowledge of industrial safety and health and attitudes toward industrial safety and health. Results: As a result of the study, harmful environments for field practices of vocational high schools were physical, chemical, ergonomic, and emotional labor, and the consequences were accidents, death by overwork, musculoskeletal diseases, etc. The materials covered students' rights and how to respond to workplace accidents in the 1st round, how to organize a workshop in the 2nd round, workplace safety and health signs in the 3rd round, prevention of musculoskeletal diseases in the 4th round, management of physical risk factors in 5th round, management of hazardous chemicals in 6th round, wearing and managing protective equipment in 7th round, first aid depending on the situation in the 8th round, CPR and defibrillator in the 9th round, sexual harassment in the 10th round, and prevention of sexual violence in the 11th round. After completing the education, their knowledge of industrial safety and health increased significantly from 6.52 points to 7.01 points. Conclusion: The results of this study suggest: first, to statistically organize the data on accidents that have occurred during field practices of vocational high schools; second, to develop a systematic curriculum for high school 1st to 3rd graders on accidents that may happen during field practices of vocational high schools.

An efficient recognition of round objects using the curve segment grouping (곡선 조각의 군집화에 의한 둥근 물체의 효과적인 인식)

  • 성효경;최흥문
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.9
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    • pp.77-83
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    • 1997
  • Based on the curve segment grouping, an efficient recognition of round objects form partially occuluded round boundaries is proposed. Curve segments are extracted from an image using a criterion based on the intra-segment curvature and local contrast. During the curve segment extraction the boundaries of pratially occluding and occuluded objects are segmented to different curve segments. The extracted segments of constant intra-segment curvature are grouped to different curve segments. The extracted segments of constant intra-segment curvature are grouped nto a round boundary by the proposed grouping algorithm using inter-segment curvature which gives the relatinships among the curve segments of the same round boundary. The 1st and the 2nd order moments are used for the parameter estimation of the best fitted ellipse with round boundary, and then recognition is perfomed based on the estimated parameters. The proposed scheme processes in segment unit and is more efficient in computational complexity and memory requirements those that of the conventional scheme which processed in pixel units. Experimental results show that the proposed technique is very efficient in recognizing the round object sfrom the real images with apples and pumpkins.

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CPU Scheduling with a Round Robin Algorithm Based on an Effective Time Slice

  • Tajwar, Mohammad M.;Pathan, Md. Nuruddin;Hussaini, Latifa;Abubakar, Adamu
    • Journal of Information Processing Systems
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    • v.13 no.4
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    • pp.941-950
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    • 2017
  • The round robin algorithm is regarded as one of the most efficient and effective CPU scheduling techniques in computing. It centres on the processing time required for a CPU to execute available jobs. Although there are other CPU scheduling algorithms based on processing time which use different criteria, the round robin algorithm has gained much popularity due to its optimal time-shared environment. The effectiveness of this algorithm depends strongly on the choice of time quantum. This paper presents a new effective round robin CPU scheduling algorithm. The effectiveness here lies in the fact that the proposed algorithm depends on a dynamically allocated time quantum in each round. Its performance is compared with both traditional and enhanced round robin algorithms, and the findings demonstrate an improved performance in terms of average waiting time, average turnaround time and context switching.

Coouping Losses of the Round HTS Wires with Stacked Filaments and Radial Filaments (적층형 필라멘트와 방사형 필라멘트 구조를 갖는 원형 초전도선의 결합손실)

  • 신정욱;차귀수;이지광;한송엽
    • Progress in Superconductivity and Cryogenics
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    • v.2 no.1
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    • pp.40-44
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    • 2000
  • The round HTS wire is easier to handle than the rectangular HTS tape. This paper describes the coupling losses of the round HTS wires by finite element method. Effect of the round HTS wire are considered. Two types of Filaments arrangement, stacked filament and radial filaments, are considered. Calculation results show that coupling losses of the round HTS wire vary only a little with the direction of external magnetic field.

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Breeding of a New Spray Chrysanthemum Cultivar, 'Dream Round' with Dark Pink Petals and Thick Stem of Anemone Type for Cut-flower (줄기가 강건하고 진분홍색인 아네모네형 절화용 스프레이 국화 신품종 '드림라운드' 육성)

  • Jung, Yun Kyung;Kim, Sung Kee;Kim, Hee Dong;Lee, Young Soon
    • Horticultural Science & Technology
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    • v.31 no.4
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    • pp.517-521
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    • 2013
  • A new cultivar Dendranthema grandiflourm 'Dream Round' was developed at Gyeonggi-do Agricultural Research & Extension Services (GARES), Korea in 2010. The variety 'Dream Round' was initially derived from a cross in 2006 between 'Hebo' a seed parent, a spray chrysanthemum cultivar with white anemone type, and 'Samos' as a pollen parent, a spray chrysanthemum variety with white anemone type. The cultivar has anemone type with white petals. Trial evaluation was conducted from 2008 to 2010 for the selection of that cultivar, including a shading culture in spring and a retarding culture in summer. The flowering time of 'Dream Round' was October 24th, and year-round flowering was possible by shading or lighting treatment. The diameter of flower of 'Dream Round' was 34.1 mm. Numbers of flowers per stem and petals per flower of 'Dream Round' were 12.8 and 26.1, respectively. Its leaf color was green (Green Group 147A) and plant height was 92.4 cm. Days to flowering of 'Dream Round' under the short day treatment was about 54 in spring, and diameter of flower of 'Dream Round' was 34.2 mm in the summer. The vase life of 'Dream Round' was 21.7 days in autumn.