• 제목/요약/키워드: side branch

검색결과 227건 처리시간 0.02초

스프링클러설비의 설계면적에 대한 연구 (A Study on Design Area of Fire Sprinkler System)

  • 정기신
    • 한국화재소방학회논문지
    • /
    • 제24권3호
    • /
    • pp.93-98
    • /
    • 2010
  • 스프링클러 설비가 중요한 화재진압설비 임에도 화재 시 헤드가 작동하는 면적인 설계면적에 대한 이해의 부족으로 설계면적의 형태를 설정하고 이를 계산하는 것이 원칙에 맞지 않게 하고 있는 것으로 나타났다. 설계면적의 형태는 정사각형으로 하거나 가지관 쪽의 길이가 교차배관 쪽의 길이보다 약간 긴 직사각형으로 하는 것이 일반적이다. NFPA에서는 가지관 쪽 길이를 교차배관 쪽 길이보다 1.2배 크게 할 것을 요구하며 FM에서는 1.4배 크게 할 것을 요구한다. 동일한 설계면적에서 가지관 쪽의 길이를 길게 하면 할수록 유량과 압력이 더 커지게 된다. 설계면적의 수리계산 결과에서 가지배관 쪽의 길이가 1.2배 크게 할 경우 정방형의 경우보다 유량은 4.6%가 커지고 압력은 4.67%가 커졌으며 1.4배 크게 할 경우 유량은 7.52%가 압력은 14.51%가 커졌다. 따라서 스프링클러 설계자들은 설비를 좀 더 안정적으로 설계하기 위하여 설계면적을 정사각형 또는 가지관 쪽의 길이를 약간 길게하는 직사각형의 형태를 갖는 일반적인 규칙을 따라야 한다.

족양명위경 하지부 유주에 관한 고찰 - 『중국침구경락통감』을 중심으로- (A Study on the Courses of Lower Limb Region of Stomach Meridian -Focused on Categorized Collection of Literatures on Chinese Meridians and Collaterals-)

  • 박상균;안성;이광호
    • Korean Journal of Acupuncture
    • /
    • 제35권3호
    • /
    • pp.117-122
    • /
    • 2018
  • Objectives : Most meridians have each well point located at the distal end of fingers or toes, congruous with their meridian courses. Exceptively, ST45(Yeotae), stomach meridian(ST)'s final point, is located at the lateral side of the tip of the second toe, while the tip of the second toe was not mentioned in the course of ST. So, we studied the course of lower limb region of ST. Methods : Courses of ST in Categorized Collection of Literatures on Chinese Meridians and Collaterals(CCM) was examined. The literatures included in CCM was selected as study subjects to be studied if the meridian route was different from "Youngchu" or more detailed notes were attached. There are 3 branches in lower limb region of ST, we analyzed theories of scholars of all time about the 3 branches of ST. Results and Conclusions : Branch 1 descends along the lateral margin of the fibula to the dorsum of foot, entering into the medial side of the middle toe. Branch 2 leaves ST36 separately, terminating at the lateral side of the middle toe. Branch 3 leaves ST42 and descends to the end of the great toe. The medial side of the middle toe equate to the lateral side of the second toe, and it is connected to ST45. So branch 1 is the main stream of ST. Branch 3 drives to the great toe passing between first and second toe, it goes medial side of LR2.

Post-Coronary Artery Bypass Grafting Myocardial Ischemia Caused by an Overgrown Left Internal Thoracic Artery Side Branch

  • Kim, Eung Re;Oh, Se Jin;Kang, Hyun-Jae;Kim, Ki-Bong
    • Journal of Chest Surgery
    • /
    • 제47권5호
    • /
    • pp.465-467
    • /
    • 2014
  • We present a patient who developed recurrent angina after coronary artery bypass grafting (CABG). Myocardial single-photon emission computed tomography (SPECT) demonstrated deterioration in the myocardial perfusion, and coronary angiography revealed an overgrown side branch of the grafted left internal thoracic artery (ITA); otherwise, there were no significant changes compared with previous imaging studies obtained after the CABG. After percutaneous embolization of the grafted left ITA side branch, the angina was resolved and myocardial SPECT showed improved perfusion.

분기관을 이용한 피스톤 펌프의 압력 맥동에 관한 연구 (A Study on Pressure Ripple of Axial Piston Pump using Branch Hose)

  • 이홍선;임태형;천세영;권순광;이창돈;양순용
    • 한국공작기계학회논문집
    • /
    • 제16권6호
    • /
    • pp.117-124
    • /
    • 2007
  • The pressure ripple in most hydraulic systems is the root cause of their noise and vibration. This paper reduced the pressure ripple using side branch hose for an axial piston pump applied to small excavator. First, in calculating open area, a new method using groove area of valve plate is proposed. Simulation model in AMESim environment is developed to verify proposed method, find effective length and diameter of branch hose. Finally, the comparisons with experiment results show that the proposed method is more effective than previous method in reducing the pressure ripple.

발병초기 Bell's Palsy 환자의 안면부 피부전기활동성 차이에 관한 연구 (Differences Between Facial Electrodermal Activities of Paralyzed Side and Those of Normal Side in Acute Stage of Bell's Palsy Patients)

  • 한경숙;남동현;고형균;박영배
    • 대한한의진단학회지
    • /
    • 제9권2호
    • /
    • pp.72-82
    • /
    • 2005
  • Background and purpose: Bell‘s Palsy is a condition that causes the facial muscles to weaken or become paralyzed. It's caused by trauma to the 7th cranial nerve, and is not permanent. The aim of this study is to be convinced of differences between facial electrodermal activities of paralyzed side and those of normal side in acute stage of Bell's Palsy patients Methods: Electrodermal activity (EDA) was performed within 1 week after the onset of facial palsy and facial nerve electromyography (EMG) at 2 weeks after the onset. The recovery of facial nerve function was documented by House and Brackmann grading. All the patients were followed up weekly until recovery or up to 6 weeks. Results: There was significant differences (conductivity A: t=3.319, p=0.002; conductivity C: t=2.699, p=0.010) between facial electrodermal conductivities of paralyzed side and those of normal side in acute stage of Bell's Palsy patients (N=45). And the result showed that logarithmic scale of electrodermal conductivity A value ratio obviousely decreased with logarithmic scale of EMG zygomatic branch amplitude ratio (r=-0.472, p=0.143); logarithmic scale of capacitance B, logarithmic scale of EMG temporal branch amplitude ratio (r=-0.422, p=0.133); logarithmic scale of conductivity C, logarithmic scale of EMG buccal branch amplitude ratio (r=-0.545, p=0.083) (N=12). Conclusion: Electrodermal conductivities increased in paralyzed facial side in acute stage of Bell's Palsy patients.

  • PDF

휴리스틱 탐색전략을 이용한 배전계통 계획의 급전선 최적 경로 선정 (Optimal Feeder Routing for Distribution System Planning Using a Heuristic Strategy)

  • 최남진;김병섭;신중린
    • 대한전기학회논문지:전력기술부문A
    • /
    • 제49권11호
    • /
    • pp.566-574
    • /
    • 2000
  • This paper propose a heuristic algorithm based on the Branch-Exchange (BE) method to solve Optimal feeder Routing(OFR) problem for the distribution system planning. The cost function of the OFR problem is consisted of the investment cost representing the feeder installation and the system operation cost representing the system power loss. We propose a properly designed heuristic strategy, which can handle the horizon-year expansion planning problem of power distribution network. We also used the loop selection method which can define the maximum loss reduction in the network to reduce calculation time, and proposed a new index of power loss which is designed to estimate the power loss reduction in the BE. The proposed index, can be considered with both sides, the low voltage side and voltage side branch connected with tie one. The performances of the proposed algorithms and loss index were shown with 32, 69 example bus system.

  • PDF

튜너 내장 자동차 조향호스의 해석 모델과 실용적 응용 (On the Analytical Model of Automotive Steering Hoses Containing Tuner and Its Practical Application)

  • 이재천;오상흔
    • 유공압시스템학회논문집
    • /
    • 제6권1호
    • /
    • pp.1-9
    • /
    • 2009
  • This study presents an analytical model of an automotive steering hose containing tuner(flexible spiral metal tube) to reduce the ripple pressure induced by steering vane pump. The double-wall side branch composed in a steering hose containing tuner was analogically considered as a filter in a conduit. Specialized test equipment was manufactured for the estimation of speed of sound in a conduit and measurement of amplitude ratio between the propagated ripple pressures of inlet and outlet of the steering hose. Experimental data of entire frequency ranges can be obtained through the test once in short time. The results of three points' measurement method and cross-correlation method to estimate the speeds of sound in a hose, tuner, and side branch respectively reveal that cross-correlation method can be used practically. The results of simulation and experiment were so close, especially in the range of engine idling speed, that the proposed analytical model in this study was validated. Sensitivity analyses and experiments show that longer tuner is preferable, and that the positive-positive composition of the steering hoses containing tuner is superior to others to attenuate ripple pressure.

  • PDF