• 제목/요약/키워드: Open-tube

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관 출구로부터 방출되는 펄스파의 수치해석적 연구 (Computational Study of The Pulse Waves Discharged From The Open End of a Duct)

  • 김희동;김현섭;권용훈;이동훈
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.355-360
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    • 2001
  • This study addresses a computational work of the impulsive wave which is discharged from the open end of a pipe. An initial compression wave inside the pipe is assumed to propagate toward atmosphere. The over pressure and wave-length of the initial compression wave are changed to investigate the characteristic values of the impulsive wave. The second order total variation diminishing (TVD) scheme is employed to solve the axisymmetric, compressible, unsteady Euler equations. The relationship between the initial compression wave form and impulsive wave is characterized in terms of the peak pressure of the impulsive wave and its directivity. The results obtained show that for the initial compression wave of a large wave-length the peak pressure of the impulsive wave does not depend on the over pressure of the initial compression wave, but for the initial compression wave of a very short wave-length, like a shock wave, the peak pressure of the impulsive wave is increased with an increase in the over pressure of the initial compression wave. The directivity of the impulsive wave to the pipe axis becomes significant with a decrease in the wave-length of the initial compression wave.

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실시간 OTT 서비스 데이터 분석: 유투브 게임방송 사례 (A Study of Analyzing Live Streaming OTT Service Data: Focused on Youtube Game Broadcasting)

  • 최민지;용혜련;황현석
    • 한국게임학회 논문지
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    • 제16권2호
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    • pp.61-74
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    • 2016
  • e스포츠의 발달로 게임을 매개로 한 여러 분야의 산업들이 함께 성장하였다. 게임방송은 다양한 플랫폼을 통해 시청자들에게 도달하면서 대중적인 게임문화 확산에 기여하고 있으며, 게임이 점차 스포츠로 인식되기 시작하면서 게임방송을 실시간으로 시청하고자 하는 수요가 늘어나고 있다. 이러한 수요와 함께 최근 OTT(Over-The-Top) 서비스를 기반으로 한 글로벌 게임중계 방송채널은 빠르게 증가하고 있는 추세이다. 이에 본 연구에서는 YouTube의 Open API 분석을 통한 글로벌 게임방송 스트리밍 현황 파악 및 시청행태를 분석하고 국내 게임방송산업의 발전을 위해 실무적인 제안을 하고자 한다. 본 연구는 방송 공급자와 시청자 모두 온라인 상태에서 실시간으로 방송을 스트리밍 하는 상태인 세션을 중심으로 방송시간 및 실시간 시청자를 카테고리, 날짜, 요일, 시간대별로 나누어 분석하였다.

일측폐 전적출술 100례에 대한 임상적 고찰: 특히 합병증의 원인에 대하여 (A Clinical Review of the 100 Cases of Pneumonectomy)

  • 김진식;김의윤;손재현
    • Journal of Chest Surgery
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    • 제3권1호
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    • pp.3-12
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    • 1970
  • During the last 10 years of period, one hundred patients with various pulmonary diseases were pneumonectomized upon at the Department of Chest Surgery of Pusan University Hospital. This paper is concerned with the clnical results of these patients along with the serious postoperative complications such as postoperative intrapleural infection and hemorrhage. The results were obtained as follows. 1.Left pneumonectomy was done in sixty-six of 100 patients [66 %] and the right one was done in the rest thirty-four[34 %]. The ratio between left and right was nearly 2:1. 2.Of all oostoperative complications, the intrapleural infection was most common, and these were 53 % in empyema thoracis and 12.7 % in pulmonary tuberculosis respectively. 3.More postoperative complications could be seen after right pneumonectomy than the left one. 4.It was thought that the postoperative intrapleural infection was closely correlated with the methods of pleural dissection at pneumonectomy,postoperatlve tube drainage, time of operation, massive hemorrhage during operation, prolongation of bleeding time, and dysfunction of the liver. 5.The repeated thoracenteses with infusion of neomycin into the infected thoracic cavity and intravenous administrations of the high units of penicillin were effective in treatment of the postoperative intrapleural infection, however, the refractory cases have to be cured by thoracoplasty with open window. 6.Immediate secondary open thoracotomy appears to be the method of choice in life saving who developed massive intrathoracic hemorrhage after pneumonectomy. 7.The mortality rate was 10 % in our cases and the main causes of death were postoperative respiratory insufficiency, pulmonary edema, hemorrhage and sudden cardiac arrest.

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개심술 환자를 위한 조기 운동프로그램의 개발 및 적용에 관한 연구 (Development and Application of an Early Exercise Program for Open Heart Surgery Patients)

  • 하이경;정연이
    • 중환자간호학회지
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    • 제4권1호
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    • pp.65-73
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    • 2011
  • Purpose: This study was to develop and evaluate stability and effects of an early exercise program for patients with open heart surgery. Methods: The subjects of this study were 30 patients who had either a coronary bypass surgery or a valvular heart surgery at a tertiary hospital in Seoul. The data was collected by observation and measurement from October 1, 2004 to November 15, 2004. Results: The early exercise program developed for this study consisted of range of motion exercise and walking. Intensity of walking was 1~3 METs and increased progressively to daily target distance. During exercise, the subjects were monitored heart rate, blood pressure and RPE (Rating of Perceived Exertion). The mean FIM (Functional Independent Measurements) score of subjects was significantly improved after the early exercise program. However, several complaints such as dizziness or pain were also reported. Most complaints were associated with chest tube and RPE. Conclusion: The early exercise program can help to recover patients' physical activities after surgery, and can be applied to most patients. Patients' RPE, dizziness and pain was possible limitations, therefore, active pain control and prevention of accidents for patients would be needed.

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고속철도용 유리애자의 진동 및 파손가능성 분석 (Analysis of Fault Possibility and Vibration of Glass Insulator on High-speed Railway)

  • 김영석;송길목;정진수;김선구;전용주;류영태
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.2044-2045
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    • 2008
  • This paper was studied fault possibility of glass insulator through the proper vibration and field vibration comparison. The proper vibration of 1 cell glass insulator have many frequency band and high amplitude showed in high frequency than low frequency. The field signal amplitude of viaduct and open route were biggest moment pantograph of high-speed rail. From the FFT analysis of viaduct and open route, in the case of positive direction, the strut tube insulator effect by vertical vibration was big, the frequency was 82.5Hz and 105Hz, respectively. However, in the case of negative direction, the vibration did not cause big effect. In comparison with the proper vibration of glass insulator, the resonance was not observed.

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SNS를 IoT 플랫폼으로 이용한 도시농장 관리시스템 개발 (Development of Urban Farm Management System using Commercial SNS as IoT Platform)

  • 류대현
    • 한국인터넷방송통신학회논문지
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    • 제13권5호
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    • pp.149-154
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    • 2013
  • IoT는 포스트 스마트폰 시대의 화두로 부상하고 있지만 표준화된 개방형 IoT 서비스 플랫폼 부재로 인해 실서비스가 쉽지 않은 실정이다. 본 연구에서는 IoT 서비스 플랫폼으로 트위트, 페이스북 또는 유튜브와 같은 상용 SNS 플랫폼을 이용하는 방안을 제안하고 구현하였다. 또한 IoT 서비스의 한 예로서 지능형 도시농장 관리시스템에 적용하였다. 본 시스템은 트위트나 페이스북 또는 유튜브와 같은 개방형 SNS 플랫폼을 활용하므로 별도의 서버 구축 및 관리 비용을 절약할 수 있다. 또한 스마트폰을 위한 앱을 개발할 필요가 없이 글로벌 대기업이 개발한 유용한 사용자 인터페이스를 활용할 수 있다.

도시철도의 열차출입문제어에 관한 연구 (A Case Study for SMRT Train Open Doors Control System)

  • 원유덕;심원섭
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2006년도 추계학술대회 논문집
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    • pp.941-946
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    • 2006
  • It followed in system development and SMRT(Seoul Metropolitan Rapid Transit Co)System reached to an automatic train operation(ATO) and driverless operation(DLM) from the manual operation due to the train driver. The train like the general bus or the car vehicle was not serial riding in a car and the Parallel concept which the numerous passenger rides in a car simultaneously occur frequently the charge of the train driver unmanned bitterly from existing manual handling was a possibility of doing, train open door control(ODM) which bites also ATO, it handles it minimized. Like this ATO/DLM, the control system which bites being a Wayside to Train communication for immediacy, it is a system of the Vital concept the immediacy of the citizen Data evil the radio information transmission and the train of the interface which is accurate from unmanned operation and, will decipher, will accomplish it will guarantee. It respects the passenger accident prevention and an air question environment improvement from subway platform and phul leys the screen door of Platform(PSD) with the fire tube frost it refers and part it treats and to sleep it does, ODM which bites is accuracy and immediacy of altitude and when seeing from the viewpoint which demands the trust of altitude, ODM system the trust of car incest interface in the equipment construction which is safe and the comparative analysis back of the system analysis against the control which bites and case study and other subway system it leads from the research which it sees and signal - train in base grudge to sleep it contributes it does.

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자동차용 GAS SPRING의 최적 설계에 관한 연구 (A Study on the Optimal Design of Gas Spring for Vehicle)

  • 김영범
    • 한국정밀공학회지
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    • 제15권11호
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    • pp.39-45
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    • 1998
  • Gas springs have been widely used in motor vehicles as well as in most areas of industry. Instead of coil springs, these gas springs are easily opreated to open(extension process) or close (compression process) the doors because $N_2$ gas with high pressure and oil are charged in tube. Most of manufacturers are using the trial & error method in order to decide its specification(reaction force, damping force), which tends to waste time and money. Therefore, gas springs have been improved by properly changing the control pressure of $N_2$ Gas with its mounting location and weight to maximize its effect and to minimize its space. Although it has been researched on damping structure to minimize impact which is applied to vehicle when its back door is fully opened, the characteristics of damping structure are not known clearly. There(ore, this paper will not only clearly define the effect of important factors(open & close force)for gas springs through theoretical analysis but also provide optimum design specification through development of program to avoid traditional method of specification determination such as the trail It error method which is widely used in whole industries including automotive industry.

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Preliminary Modelling of Plasco Tower Collapse

  • Yarlagadda, Tejeswar;Hajiloo, Hamzeh;Jiang, Liming;Green, Mark;Usmani, Asif
    • 국제초고층학회논문집
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    • 제7권4호
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    • pp.397-408
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    • 2018
  • In a recent tragic fire incident, the Plasco Tower collapsed after an intense outburst of fire lasting for three and a half hours and claiming the lives of 16 firefighters and 6 civilians. This paper will present continuing collaborative work between Hong Kong Polytechnic University and Queen's University in Canada to model the progressive collapse of the tower. The fire started at the 10th floor and was observed to have travelled along the floor horizontally and through the staircase and windows vertically. Plasco Tower was steel structure and all the steel sections were fabricated by welding standard European channel or angle profiles and no fire protection was applied. Four internal columns carried the loads transferred by the primary beams, and box columns were constructed along the perimeter of the building as a braced tube for resisting seismic loading. OpenSees fibre-based sections and displacement-based beam-column elements are used to model the frames, while shell elements are used for the reinforced concrete floor slabs. The thermal properties and elevated temperature mechanical properties are as recommended in the Eurocodes. The results in this preliminarily analysis are based on rough estimations of the structure's configuration. The ongoing work looks at modeling the Plasco Tower based on the most accurate findings from reviewing many photographs and collected data.

An unstable patient with a large sucking chest wound managed with gauze packing for preventing tension and bleeding control before surgery in Korea: a case report

  • Chang-Sin Lee;Min-Jeong Cho;Tae-Wook Noh;Nak-Jun Choi;Jun-Min Cho
    • Journal of Trauma and Injury
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    • 제37권2호
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    • pp.147-150
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    • 2024
  • This case report describes the management of a 51-year-old female patient who arrived at the emergency room with a stab wound to the upper right chest. Immediate medical interventions were undertaken, including blood transfusions and endotracheal intubation. To prevent tension and control bleeding, gauze packing was applied directly through the large open wound. Further surgical exploration identified a laceration in the lung, necessitating a right upper lobe resection. Postoperatively, the patient's vital signs stabilized, and she was subsequently discharged without complications. This case highlights the decision-making process in selecting between an emergency department thoracotomy and an operating room thoracotomy for patients with penetrating chest trauma. It also illustrates the role of gauze packing in managing tension and hemorrhage. In summary, gauze packing can be an effective interim measure for stabilizing patients with traumatic injuries, unstable vital signs, and large open chest wounds, particularly when a chest tube is already in place, to prevent tension and facilitate bleeding control prior to surgical intervention.