• Title/Summary/Keyword: COR

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Modelling of variable coefficient of restitution and its application to impact analysis of dynamic systems (반발계수의 모델링과 동적 시스템의 충돌 분석으로의 적용)

  • Ryu, Hwan-Taek;Choi, Jae-Yeon;Kwon, Young-Hun;Yi, Byung-Ju
    • The Journal of Korea Robotics Society
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    • v.10 no.4
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    • pp.200-212
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    • 2015
  • In classical dynamics, the coefficient of restitution is one of variables to estimate the amount of impulse. In general, we have considered the coefficient of restitution as a constant value. However, coefficient of restitution (COR) is the function of contact material and colliding velocity. Furthermore, COR is also a function of contact area. Thus, without considering the variable characteristic of COR, the actual motion of an object just after impact is not the same as we expect. A general COR model is proposed in this work and its effectiveness is verified through a cart impact experiment and its result is applied to simulation of a ball impact problem. A three-degree-of-freedom manipulator is employed as a test-bed.

cor triatriatum dexter combined with pulmonary stenosis (폐동맥 협착증을 동반한 우측 삼중심방 -1예 치험-)

  • Kim, Hyuck;Lee, Joon-Young;Lee, Hong-Sub;Jun, Suk-Chul;Lee, Kyu-Whan;Kim, Chang-Ho
    • Journal of Chest Surgery
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    • v.19 no.2
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    • pp.313-318
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    • 1986
  • A rare anomaly, Cor triatriatum dexter combined with pulmonary stenosis and patent foramen ovale in a 2-years- old female is presented. Abnormal embryologic development of the right sinus venosus valve caused partial membranous septation of the right atrium. Most cases have been recorded at necropsy either as an incidental finding or in association with severe congenital heart disease. In this case, Cor triatriatum dexter was diagnosed preoperatively by cineangiography and echocardiography.

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Cor Triatriatum (A case report) (삼중방심 치험 1례)

  • 인강진
    • Journal of Chest Surgery
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    • v.22 no.4
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    • pp.667-671
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    • 1989
  • Cor triatriatum is a rare congenital malformation of the heart in which a diaphragm stretches in a transverse plane through the left pulmonary venous chamber, thus creates two subchambers. The proximal chamber connects with the pulmonary veins, and the distal one has left auricle and the mitral valve. A 3 year old boy who had Cor triatriatum underwent surgical excision of the abnormal diaphragm in March, 1989 in Chungnam University Hospital. An obliquely oriented fibromuscular diaphragm divided the left atrium into a proximal chamber which was connected to the pulmonary veins and a distal chamber which had the atrial appendage and the mitral valve. The opening in the diaphragm was 5 mm in diameter. There were no associated abnormalities. The abnormal diaphragm was completely excised. The postoperative result was excellent.

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Implementation of external corrosion direct ass- essment (ECDA) on water pipelines (매설배관 방식시스템의 효율 향상을 위한 실효성 제고)

  • Pyo, Min-Tae;Kim, Byoung-Jig;Jung, Sung-Won;Choi, Jun;Li, Seon-Yeob
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.2045_2046
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    • 2009
  • 광역상수도관에 대하여 외면부식직접평가(ECDA)를 실시하였다. ECDA평가는 과거 방식이력 등에 대한 사전검사, CIPS-DCVG-비저항 측정의 3단계 간접검사를 통해서 배관의 부식가능성이 큰 지점을 검출하여 위험성 우선순위를 판정하고 최종적으로 굴착을 통한 직접 검사 우선순위를 선정하였다. 직접 검사후 사후단계로 수집한 모든 데이터를 종합적으로 분석하여 검사구간의 건전성을 종합 평가를 하였다. 이러한 검사기법을 도입함으로써 배관의 부식위험지역을 파악하고 적절한 조치를 취할 수 있는 체계적인 근거를 마련한 것으로 판단하였다.

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Restitution Behaviors and Mechanical Characteristics of Strings (스트링의 반발거동과 역학적 특성)

  • 김태용;박진무
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.11a
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    • pp.543-546
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    • 2000
  • Static and dynamic experiments were done to study on the restitution behaviors of strings. The elastic and viscoelastic model were compared. To apply a linear viscoelastic model (Kelvin model) to longitudinal behaviors of strings, static and dynamic tensile tests were done. Using their results, it should be intended to acquire damped stress (Stress related to velocity), and to calculate the viscoelastic coefficient. Fixing both ends, string was pushed by the loadcell attached to the tensile tester. The experimental results were in accordance with the calculated results using the Kelvin model acquired from the results of longitudinal tensile test. But the results of falling mass experiments, the behaviors of strings were near to elastic model. The clamping condition of strings in both sides has an effected on the value of COR. The smaller contact area, the grower the value of COR.

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AutoCor: A Query Based Automatic Acquisition of Corpora of Closely-related Languages

  • Dimalen, Davis Muhajereen D.;Roxas, Rachel Edita O.
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2007.11a
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    • pp.146-154
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    • 2007
  • AutoCor is a method for the automatic acquisition and classification of corpora of documents in closely-related languages. It is an extension and enhancement of CorpusBuilder, a system that automatically builds specific minority language corpora from a closed corpus, since some Tagalog documents retrieved by CorpusBuilder are actually documents in other closely-related Philippine languages. AutoCor used the query generation method odds ratio, and introduced the concept of common word pruning to differentiate between documents of closely-related Philippine languages and Tagalog. The performance of the system using with and without pruning are compared, and common word pruning was found to improve the precision of the system.

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Cor Triatriatum Sinistrum with an Ostium Primum Atrial Septal Defect in a Siamese Cat

  • Choi, Ran;Hyun, Chang-Baig
    • Journal of Veterinary Clinics
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    • v.25 no.6
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    • pp.518-522
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    • 2008
  • An approximately 8-month-old, 2.61 kg, male Siamese kitten was referred with primary complaints of a 1-week history of respiratory distress, exercise intolerance and dyspnea. Diagnostic studies identified III/VI systolic murmur in the cardiac auscultation, right ventricular enlargement patterns in the electrocardiogram, pleural effusion and right-sided cardiomegaly in the thoracic radiography, and right marked ventricular dilatation, right atrial enlargement, atrial septal defect and abnormal left atrium divided by fibromuscular membrane. Based on these findings, the case was diagnosed as cor triatriatum sinistrum complicated with an ostium primum atrial septal defect. The cat was rescued with furosemide, nitroglycerine, oxygen supplement and fluid removal from pleural cavity.

Regeneration of Exhausted Activated Carbon by a Countercurrent Oxygen Reaction

  • 류건상;김태동;김유항
    • Bulletin of the Korean Chemical Society
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    • v.20 no.12
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    • pp.1447-1450
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    • 1999
  • Countercurrent oxygen reaction (COR) was developed and evaluated for regeneration of exhausted activated carbon. Whether the regeneration technique is feasible or not is affected strongly by gradual loss and physical changes of activated carbon, energy consumption, and effective removal of adsorbed materials during the process. Various parameters such as reaction temperature, the loss of activated carbon, surface area, pore volume, surface structure, adsorptive property, etc. were examined to determine the effectiveness of COR. The results of these tests showed that the parameters were strongly dependent on oxidant flow rate, and suggest that the newly developed COR is comparable and, in some ways, possibly superior to conventional regeneration techniques because the overall process runs in a single step and is less energy intensive, and also because the adsorptive capacity of exhausted activated carbon was completely recovered.

Preparation and characterization of Poly (ethylene terephthalate) (PET) (가지 달린 poly (ethylene terephthalate) (PET)의 제조와 물성에 관한 연구)

  • Kim, Soochan;Park, Sungshin;Sooyun Jung;Kim, Jungsoo;Seungsoon Im
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10b
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    • pp.203-204
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    • 2003
  • Generally, polymeric foam has many advantages, such as light-weight, good impact absorptivity and adiabatic properties. Poly (ethylene terephthalate) PET has good recyclability and no toxicity. Hence, if we make foam of PET, it could be used for various applications such as heat insulating material, recyclable packing material, and food vessel. Thus these properties are attractive interests to manufacturers. (omitted)

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Les problèmes et les solutions de thèâtre musical corèen (한국 라이선스 뮤지컬의 현실과 개선에 대한 연구)

  • Kim, Gyunhyeong
    • (The) Research of the performance art and culture
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    • no.18
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    • pp.257-282
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    • 2009
  • Le $th{\acute{e}}{\hat{t}}re$ musical en $Cor{\acute{e}}e$ est devenu aujourd'hui une mode. Beaucoup parlent de musical, mais beaucoup de musicals sont $mont{\acute{e}}s$ sur la $sc{\grave{e}}ne$ sans des recherches $n{\acute{e}}cessaires$ suffisantes. C'est pour cette raison que la plupart des spectacles musicaux qui sont $cr{\acute{e}}es$ en $Cor{\acute{e}}e$ sont $destin{\acute{e}}s$ en faillite $d{\grave{e}}s$ la naissance. D'ailleurs les musicals $liscenci{\acute{e}}s$ par $l^{\prime}Am{\acute{e}}rique$, la France qui sont $mont{\acute{e}}s$ sur la $sc{\grave{e}}ne$ de $Cor{\acute{e}}e$ aujourd'hui sont assez pour nuire le $march{\acute{e}}$ $cor{\acute{e}}en$ $constitu{\acute{e}}$ autour de musical. Quels sont donc les $probl{\grave{e}}mes$ que posent les musicals $liscenci{\acute{e}}s$? $Premi{\grave{e}}rement$ ils encouragent la mime, pas la $cr{\acute{e}}ation$. En d'autre terme, les musicals $liscenci{\acute{e}}s$ que les $Cor{\acute{e}}ens$ montent sur la $sc{\grave{e}}ne$ ne sont pas les $cr{\acute{e}}ations$ propres chez les $Cor{\acute{e}}ens$, par contre, ces derniers sont $demand{\acute{e}}s$ de suivre ${\grave{a}}$ la mot les indications $dict{\acute{e}}es$ par le droit d'auteur. Les $cr{\acute{e}}ateurs$ $cor{\acute{e}}ens$ ne sont pas libres de $cr{\acute{e}}ation$. $Deuxi{\grave{e}}mement$ les musicals ${\grave{a}}$ la mode ont pouvoir de $d{\acute{e}}truire$ la $diversit{\acute{e}}$ de l'homme. L'homme se $caract{\grave{e}}rise$ par la $diversit{\acute{e}}$ et se $diff{\grave{e}}re$ l'un par rapport ${\grave{a}}$ l'autre. C'est l'essence de l'homme. Tous sont $diff{\acute{e}}rents$. Pourtant le musical qui $r{\grave{e}}gne$ sur tous genres de spectacles d'aujourd'hui de $Cor{\acute{e}}e$ ne laisse pas vivre d'autres genres de spectacles, la danse, le $th{\acute{e}}{\hat{a}}tre$, etc. Seul le musical est $compt{\acute{e}}$. $Troisi{\grave{e}}mement$ le musical ne peut pas nier $compl{\grave{e}}tement$ son origine commerciale. En fait le musical est devenu une chose important depuis des investigations immenses par le gouvernement $d^{\prime}Am{\acute{e}}rique$ pour donner des travails aux gens. Donc, $d{\grave{e}}s$ le $d{\acute{e}}but$, il n'y avait pas de $consid{\acute{e}}rations$ artistiques dans et sur le musical. Comme c'est par le commerce que le musical est $r{\acute{e}}pandu$, s'il y aura un $probl{\grave{e}}me$ quelconque, il est $tr{\grave{e}}s$ possible qu'on cherche ${\grave{a}}$ $r{\acute{e}}soudre$ le $probl{\grave{e}}me$ par la vue de commerce. En comprenant les $probl{\grave{e}}mes$ $mentionn{\acute{e}}s$ $l{\grave{a}}$-dessus, il faut $pr{\acute{e}}parer$ le changement de $march{\acute{e}}$ $cor{\acute{e}}enne$ de musical. Le moyen le plus $su{\hat{r}}$ de se $pr{\acute{e}}parer$ est de trouver la $r{\acute{e}}solution$ dans la culture. Pourtant cette $derni{\grave{e}}re$ ne signifie pas la tradition comme $c^{\prime}{\acute{e}}tait$ le cas $jusqu^{\prime}{\grave{a}}$ aujourd'hui, car les $Cor{\acute{e}}ens$ ne sont pas ${\acute{e}}duqu{\acute{e}}s$ par cette $derni{\grave{e}}re$. La $modernit{\acute{e}}$, disons occidentale, traverse la $Cor{\acute{e}}e$. Donc, la signification du mot 'culture' doit ${\hat{e}}tre$ $bas{\acute{e}}e$ sur la tradition et la $modernit{\acute{e}}$ en $m{\hat{e}}me$ temps.