• Title/Summary/Keyword: general circulation

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Enhance of Dissolved Oxygen Rate using a 3-prong Nozzle (3구 노즐을 이용한 산소의 용존율 향상)

  • Park, Young-Seek
    • Journal of Environmental Science International
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    • v.24 no.7
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    • pp.947-954
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    • 2015
  • Dielectric barrier discharge plasma is a new technique in water pollutant degradation, which that is characterized by the production of chemically active species such as hydroxyl radicals, ozone, hydrogen peroxide, etc. If dissolving of plasma gas generated in the plasma reaction has increased, it is possible to increase the contaminant removal capacity. In this study, the improvement on the dissolving performance of plasma gas was evaluated by the indirect method measuring the overall oxygen transfer coefficient. Experiments were conducted to examine the effects of nozzle type, distance from water surface, air supply rate and liquid circulation rate. The experimental results showed that the $K_{La}$ value of the 3-prong nozzle is 2.67 times higher than the diffuser. The order of $K_{La}$ value with nozzle type ranked in the following order: 3-prong nozzle (inner diameter, less 1 mm) > circular nozzle (inner diameter, 1.5 mm) > ellipse nozzle (short diameter 1 mm, long diameter 2.5 mm) > circular nozzle (inner diameter, 3 mm). Optimal liquid circulation rate was appeared to be 1.7 L/min, the value of $K_{La}$ was 0.510 1/min. The value of $K_{La}$ with increasing air supply rate was revealed in the form of an exponential such as $K_{La}=0.3581e^{0.2919^*air\;flow\;rate}$.

A Study on the Planning Directions based on the Analysis of the Campus Plan (대학 캠퍼스계획의 분석을 통한 방향설정에 관한 연구)

  • Ahn, Kyung-Hwan
    • Journal of the Korean Institute of Educational Facilities
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    • v.16 no.5
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    • pp.27-33
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    • 2009
  • The existing universities enlarged the scope, filled up the facilities. And many new universities are founded by increase of university students, the change of curriculum and extension of installations for new curriculum. However, the planning for university campus hinders desirable activities in campus and also the origin function of university, because of the problems caused by an application of a uniform planning standard that lacks in logical analysis and such a short step as the occasion demands for the growth and the change of the university campus changing more rapidly than any other field in society. This dissertation is for space program beginning from architectural explanation and basic planning concluding a general structure-planning for land utility, circulation planning, and building layout planning in order to find the practical solution for the applicable campus plan. The contents of this dissertation is summarized below. First, I studied the characteristics of the university, the structure of the university facilities and the expansion the development process of the campus. Second, through the case study of domestic campus planning, I analyzed the characteristics and the problems about space programming, facility layout planning, circulation planning and exterior space planning. Third, in the basis of the above analyses, I set up the directions of comprehensive campus master plan.

Analysis on the Characteristics of Climate about Korean Summer Season 1998

  • Cha, Eun-Jeong;Choi, Young-Jean;Oh, Jai-Ho
    • International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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    • v.26 no.1
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    • pp.31-41
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    • 1998
  • The climatic characteristics of summer in 1998 are analyzed with the weather observational data and the upper air observational data. The temperature of that period is lower than that of normal years and the precipitation is larger. Due to the heavy rainfall which started at July 31, rain pured down compared to normal years and the maximum precipitation recorded at the many observational stations, particularly in Seoul, Kyunggi-Do region and mountanious districts like Taegwallyong, Mt. Sokri and Mt. Chiri. The patterns of general circulations in 1982/98 and 1997/98 are compared each other and are analyzed. The anomaly patterns of stream functions on winter in two El Nio years are simialr. The counterclockwise circulation occurred near the date line and the clockwise circulation was appeared near the Hwanam region and Alaska. These patterns are opposite to those of La Nia year, 1988/89. And the anomaly patterns of 500hPa geopotential height in summer are similar, too. The low temperature and much rain were dominated in summer of 1997/98. These phenomena is similar to the existing results of research, that temperature is low and precipitation is large in summer of El Nio years.

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Stroke after percutaneous transhepatic variceal obliteration of esophageal varix in Caroli syndrome

  • Lee, Yoo Min;Lee, Yoon;Choe, Yon Ho
    • Clinical and Experimental Pediatrics
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    • v.56 no.11
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    • pp.500-504
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    • 2013
  • Here we present the case of an 11-year-old female patient diagnosed with Caroli syndrome, who had refractory esophageal varices. The patient had a history of recurrent bleeding from esophageal varices, which was treated with endoscopic variceal ligation thrice over a period of 2 years. However, the bleeding was not controlled. When the patient finally visited the Emergency Department, the hemoglobin level was 4.4 g/dL. Transhepatic intrajugular portosystemic shunt was unsuccessful. Subsequently, the patient underwent percutaneous transhepatic variceal obliteration. Twenty hours after this procedure, the patient complained of aphasia, dizziness, headache, and general weakness. Six hours later, the patient became drowsy and unresponsive to painful stimuli. Lipiodol particles used to embolize the coronary and posterior gastric veins might have passed into the systemic arterial circulation, and they were found to be lodged in the brain, kidney, lung, and stomach. There was no abnormality of the portal vein on portal venography, and blood flow to the azygos vein through the paravertebral and hemiazygos systems was found to drain to the systemic circulation on coronary venography. Contrast echocardiography showed no pulmonary arteriovenous fistula. Symptoms improved with conservative management, and the esophageal varices were found to have improved on esophagogastroduodenoscopy.

Evaluation of North Pacific Intermediate Water Simulated by HadGEM2-AO (HadGEM2-AO의 북태평양 중층수 모의 성능 평가)

  • Min, Hong Sik;Yim, Bo Young
    • Ocean and Polar Research
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    • v.37 no.4
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    • pp.265-278
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    • 2015
  • We analyzed the North Pacific Intermediate Water (NPIW) that was simulated in 25 coupled general circulation models (CGCMs) using historical and Representative Concentration Pathway 4.5 (RCP4.5) scenario experiments of Coupled Model Intercomparison Project Phase 5 (CMIP5), focusing on the evaluation of the performance of HadGEM2-AO. A large inter-model diversity in salinity, density, and depth of the NPIW exists even though the multi-model ensemble mean (MME) is comparable to observations. It was found that the depth of the NPIW tends to be deeper in the models in which the NPIW is relatively saltier. HadGEM2-AO simulates the lightest NPIW having the lowest salinity at shallower depth, compared with other CGCMs. Future projections of the NPIW show that the temperature of the NPIW increases, but the density decreases in all CMIP5 models. It was shown that the salinity of the NPIW decreases in most models and the decrease tends to be larger in models simulating the lighter NPIW. The HadGEM2-AO projects moderate changes in the temperature and density of the NPIW out of the CMIP5 models.

A Study on the Effects of Flexible Operation of Imported Grain Transportation Vehicles on Logistics Costs by Considering Empty Transfer Rates (공차율을 고려한 유연한 수입곡물 화물차운영이 물류비용에 미치는 영향에 관한 연구)

  • Kim, Byeong Chan;Yang, Dae Yong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.4
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    • pp.193-203
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    • 2012
  • This study analyzed regular transportation costs between port warehouses and processing plants and between processing plants and central distribution centers and further transportation costs relations according to empty transfer rates in each circulation by examining the distribution routes of imported grain including wheat, barley, corn, and soybean, namely port warehouses, processing plants, and central distribution centers. Based on the results, the study compared and reviewed the logistics transportation costs. The analysis results of the alternative model show that logistics operational costs could be considerably cut down by introducing a flexible vehicle transportation operational method, which is to change the vehicle loading parts for proper substitute transportation after unloading and transport them to other locations such as central distribution centers instead of returning empty, as an alternative to high operational costs deriving from empty vehicle operation in each circulation after unloading items in case of transportation of imported grain and processed items. The results allow for a more realistic approach to general problems with large-scale distribution network operation and provide a theoretical foundation to serve as a guide to establish policies for corporate operation of imported grain logistics systems.

Power Circulation Characteristics of Hydro-Mechanical transmission System in Steering (정유압 기계식 변속기의 조향시 동력 순환 특성)

  • Kim, J. S.;Kim, W.;Jung, Y. H.;Jung, S. B.;Kim, H. S.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.2
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    • pp.13-22
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    • 1997
  • Power flow characteristics of a hydro-mechanical transmission system(HMT) are investigated for tracked vehicle in steering. A HMT consisting of two hydrostatic pump motors(HST), several planetary gear trains and steer differential gear is considered. In order to obtain the direction and magnitude of the power flow of the HMT, network theory for the general power transmission is used. Network model for the HMT in steering is developed, which consists of shafts, nodes and transmission elements such as clutch, gear, etc. Power flow analysis procedure consists of two stages : (1) traction force analysis in steering, (2) power flow analysis in HMT. Torque and speed of every transmission element of the HMT is determined from the network analysis. Also, efficiency, mechanical and hydraulic power loss including HST, are obtained. In addition, the regenerative power flow resulting from steering can be studied in graphic display. The power flow analysis program(PCSTEER) developed in this work can be used as a useful design tool for the tracked vehicle with HMT.

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Congenital Diaphragmatic Hernia and Eventration Requiring Operation in the first 24hrs of Life - A report of 5 cases - (생후 24 시간 이내에 수술을 요하는 선천성 횡경막 탈장 및 횡경막 내번증5례 보고)

  • Lee, Cheol-Beom;Hong, Gi-Ung;No, Jin-Sam
    • Journal of Chest Surgery
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    • v.21 no.1
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    • pp.175-183
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    • 1988
  • Congenital diaphragmatic hernia [CDH] is a surgical emergency in the newborn infant because it causes severe cardiorespiratory distress. Congenital diaphragmatic eventration [CDE] may also produce severe cardiorespiratory distress in the newborn infant. CDH is an anatomically simple defect that can be easily repaired by reduction of the displaced viscera from the pleural cavity and closure of the diaphragmatic defect. But these infants mortality has not been reduced and still remains very high. The barrier to survival is pulmonary parenchymal and vascular hypoplasia as well as the complex syndrome of persistent fetal circulation. Between May, 1985 and Oct, 1987, 4 neonates with CDH and 1 neonate with CDE were seen in respiratory distress within 12 hrs of birth at St. Francisco general hospital. Each had severe acidosis and hypoxia. And was transferred from a local clinic. They were surgically repaired within 24 hrs of birth. Three neonates lived and two died. Two of the three neonates with CDH operated in the first 6 hrs died. The remaining two [one with CDH, the other with CDE] operated between 6hrs and 24 hrs lived. One case of mortality was combined with bilateral pulmonary hypoplasia and contralateral pneumothorax. The other one case of mortality was combined with complex syndrome of persistent fetal circulation after honeymoon period.

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A Comparative Study of the Remodeling of an Existing Hospital and the Remodeling of an Existing Hospital with the Addition of an Annex - Focused on Adventist General Hospital in Seoul - (기존병원 중심의 리모델링과 새 병원중심의 리모델링 비교연구 - A 종합병원을 중심으로 -)

  • Hong, Soon-Myung
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.14 no.1
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    • pp.7-20
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    • 2008
  • This study is an analysis of the characteristics between the remodeling of an existing hospital and the remodeling of an existing hospital with the addition of a new annex. The comparison of the two remodeling methods focused on the difference of gross area, circulation system, improvement of hospital function, profitability of remodeling construction, and so on. The result of this study can be summed up as follows. The remodeling of an existing hospital with a new annex has the merit of enlarging new areas, promoting the function of the hospital, changing the inner circulation system, and facilitating the construction. However, it has the demerit of requiring too much money and expanded space for the construction. Therefore, it is possible to use the existing hospital remodeling method for small scale hospitals that do not have many patients, but it would be necessary for big scale hospitals with many patients to adopt the method of remodeling the existing hospital with the addition of an annex.

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A study on better wire protector of equipment on the Circulating Current in Catenary System (순환전류에 대한 전철설비 보호카바 개선 연구)

  • Kang, Seung-Wook;Kim, In-Chol;Kim, Hyo-Jin;Kim, Dae-Sik;Baek, Seong-Hyun;Han, Sang-Ok
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.375-378
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    • 2007
  • In these days, Korea Railway apply simple catenary system to general lines and high speed lines of Korea Electric Railway. Circulation Current in catenary system frequently bring undesirable consequences. Namely, the Connector wire has many problems according to a flow of excessive circulation (or traction current) and a sudden rise of temperature on catenary when electric car or locomotive is running in high speed. The occurrence of events by the load increasement do considerable damages to peoples, organizations and systems. On a case by case accidents, the reeltype protective cover as part of various methods has some problems. In this project, we proposed the improved changes on the catenary system of a improvement and change of a messenger wire protector, improvement of connector wire's institution angle and of a replacement the connector wire with a dropper. Its tridimensional space limitation dictated the scale of the $32{\times}{\Phi}55$ to be as small as possible. It is easier to install than work by the existing cover on the messenger wire.

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