• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.3
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• pp.209-221
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• 2002

In the present paper, a method which enhances the circulation of harbor waters by using wave energy was investigated. The overflow levee was selected as a coastal structure helping the harbor circulation, and was applied to Jeju-outer-port site so as to estimate its effectiveness quantitatively in probabilistic point of view. It was assumed that sea water influx rate through the overflow levee into the harbor depended upon wave height and tidal level and a functional relationship among them was calculated using the results of hydraulic experiment. The probability distribution of water influx could be obtained from hindcasted wave data and measured tidal elevations at Jeju harbor. The Gamma distribution was appeared to best fit the estimated influx distribution, and the optimal location of the levee was discussed. Finally, water quality purification effect was investigated by computing the contaminant material dispersion according to whether the levee was or not.

• Korean Institute of Interior Design Journal
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• v.23 no.6
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• pp.195-203
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• 2014

This study selects factors affecting form type of hospital architecture by considering studies and references on hospital architecture type in korea and other countries in general. Also this study classifies general hospitals chronologically and analyzes type change of general hospitals in relation with periodic change of healthcare environment. Through this, this study aims to analyze chronological change of general hospitals' form type and provide the current of hospital architecture's general type. The form type classification of this study is classification according to the form of ward, classification according to the relationship between ward and D.T.D(Diagnostic and Treatment department), classification according to the relationship between O.P.D(Out Patient department) and D.T.D, classification according to the rate of centralization, classification according to the circulation system. The form type of ward changed from plate type to tower type, and the circulation system of ward changed from middle corridor to double corridor, the number of Team Nursing chaged from 1 to 2 in 1990. On the other hand the chage of others classifications took place from 1990' to 2010'. It is judged that this overall change is appeared by a change from an inpatien-oriented system to an outpatient-oriented system followed by an increase in number of outpatients, an increase in amenities in ground floor and adoption of healing environment for patients and visitors.

• Journal of the Korean Solar Energy Society
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• v.27 no.3
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• pp.45-54
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• 2007

For a conventional natural-circulation type solar water heater, the pressure head is limited by the height between the storage tank and hot water tap. Therefore, it is difficult to provide sufficient hot water flow rate for general usage. This study deals with a design modification of the storage tank to utilize the tap-water pressure to increase hot-water supply Based on fluid dynamic and heat transfer theories, a series of modeling and simulation is conducted to achieve practical design requirements. An experimental setup is built and tested and the results are compared with theoretical simulation model. The storage tank capacity is 240 l and the outer diameter of piping was 15 mm. Number of tube turns tested are 5, 10, and 15. Starting with initial storage tank temperature of $80^{\circ}C$, the temperature variation of the supply hot water is investigated against time, while maintaining minimum flow rate of 10 1/min. Typical results show that the hot water supply of minimum $30^{\circ}C$ can be maintained for 34 min with tap-water supply pressure of 2.5 atm, The relative errors between modeling and experiments coincide well within 10% in most cases.

• International Journal of Vascular Biomedical Engineering
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• v.2 no.2
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• pp.16-26
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• 2004

The object of this study is to develop a mathematical model of the hemodialysis system including the mechanism of solute kinetics, water exchange and also cardiovascular dynamics. The cardiovascular system model used in this study simulates the short-term transient and steady-state hemodynamic responses such as hypotension and disequilibrium syndrome (which are main complications to hemodialysis patients) during hemodialysis. It consists of a 12 lumped-parameter representation of the cardiovascular circulation connected to set-point models of the arterial baroreflexes, a kinetic model (hemodialysis system model) with 3 compartmental body fluids and 2 compartmental solutes. We formulate mathematically this model in terms of an electric analog model. All resistors and most capacitors are assumed to be linear. The control mechanisms are mediated by the information detected from arterial pressoreceptors, and they work on systemic arterial resistance, heart rate, and systemic venous unstressed volume. The hemodialysis model includes the dynamics of urea, creatinine, sodium and potassium in the intracellular and extracellular pools as well as fluid balance equations for the intracellular, interstitial, and plasma volumes. Model parameters are largely based on literature values. We have presented the results on the simulations performed by changing some model parameters with respect to their basal values. In each case, the percentage changes of each compartmental pressure, heart rate (HR), total systemic resistance (TSR), ventricular compliance, zero pressure filling volume and solute concentration profiles are represented during hemodialysis.

• Journal of Chest Surgery
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• v.29 no.11
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• pp.1263-1266
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• 1996

We have experienced a case of coronary artery bypass surgery without extracorporeal circulation through limited anterior thoracotomy. The lesion was a single vessel disease involving the take off of the left anterior descending artery(LAD) which showed tubular lesion with irregular contour and eccentric stenosis of more than 95% luminal narrowing. Percutaneous transluminal coronary angioplasty(PTCA) seemed to have moderate success rate and moderate complication rate. A segment of left internal mammary artery(LIMA) from the second rib down to the sixth rib was harvested through the bed of resected fourth costal cartilage. Anastomosis between LIMA and LAD was performed under beating condition. The patient was extubated in the operation room and showed excellent postoperative course without complications. The coronary angiography on the postoperative 7th day revealed good patency at the anastomosis site.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.27-34
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• 2002

Clinical study on hemodynamics of healthy elders before and after tread mill. Using doubleblind, placebo-controlled study design. Seventy-five 50-70 years old volunteers without organic disease were divided into two groups, Ginseng group and control group. Each subject was received 3 g Korea Red Ginseng (KRG) capsules or placebo per day for 4 weeks. Before and after administration 4 weeks, the symptoms were asked and hemodynamics parameter such as pump function, systolic function, preload and afterload were recorded before and after tread mill 1,5, 10 minutes by the method of thoracic impedance cardiograph. The result showed that Ginseng could improve quality of life, had obvious effect of increasing PEP (pre-ejection period), PEP/LVET (pre-ejection period/left ventricular ejection period), PCWP (wedged pressure pulmonary capillary). The change rate of HR (heart rate), SV (stroke volume) in KRG group were much lowered, while EF (ejection fraction), LVET (left ventricular ejection period), LVEDP (left ventricular end diastolic pressure) was recovered much quickly. The circulation showed Ginseng could improve the quality of life though its promoting circulation function which are increasing both the systolic function and the preload.

• Journal of Information Science Theory and Practice
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• v.9 no.2
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• pp.33-46
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• 2021

The purpose of this paper is to analyze the case of 'drive-thru' services newly introduced and tried in libraries in Korea under the influence of COVID-19, and to develop and propose a service model so that this service can be continuously applied to all libraries in the future. Therefore, the method of study was selected and analyzed by selecting one of the representative libraries that provide related services in Seoul Special City, Incheon Metropolitan City, and Anyang City of Gyeonggi Province. In addition, a focus group interview was conducted with twelve people in charge to find a way to apply the drive-thru service to the library. As a result, the library's drive-thru service is a way to fulfill the library's original purpose of providing information materials while minimizing faceto-face contact with users. It was concluded that it is a suitable method for a library of complex buildings, where there is a lack of parking space. In addition, it was deduced that it may be one of the ways to use the library efficiently for office workers who are unable to use library services during the opening hours. Therefore, if the drive-thru service is implemented according to the developed model, it is expected to increase the library visit rate and data utilization rate.

• Journal of Distribution Science
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• v.12 no.3
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• pp.99-103
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• 2014

Purpose - The objective of this study was to examine the volatility of the exchange rate of the Somali shilling (SoSh) during 2010, especially the exchange rate between the Somali shilling and US dollar. Research design, data, and methodology - The study employed aquantitative research design; the data was analyzed using contents analysis for the data pertaining to the exchange rate between the US dollar and Somali Shilling in 2010. Results - The main findings were that the exchange rate was very volatile during 2010 because of three sources: (1) Imbalance of demand and supply in the money market, (2) People adopting the US dollar as the medium of exchange forgoods and services, thereby reducing the circulation of the SoSh, and (3) Lack of a strong central bank. Conclusions - The study suggested three possible remedies: the establishment of an effective central bank that matches the demand and supply of the currencies, adoption of the Somali shilling as the official currency base for the prices of commodities, and minimizing the imports into the country and maximizing its exports, to support the strengthening of the Somali shilling.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.639-646
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• 2000

Hot air heater with light oil combustion is the most common heater for greenhouse heating in the winter season in Korea. However, since the heat efficiency of the heater is about 80%, considerable unused heat in the form of exhaust gas heat discharges to atmosphere. In order to capture this exhaust gas heat a heat recovery system for plant bed heating in the greenhouse was built and tested in the hot air heating system of greenhouse. The system consists of a heat exchanger made of copper pipes, ${\phi}\;12.7{\times}0.7t$ located inside the rectangular column of $330{\times}330{\times}900mm$, a water circulation pump, circulation plastic pipe and a water tame The total heat exchanger area is $1.5m^2$, calculated considering the heat exchange amount between flue gas and water circulated in the copper pipes. The system was attached to the exhaust gas path. The heat recovery system was designed as to even recapture the latent heat of flue gas when exposing to low temperature water in the heat exchanger. According to performance test it can recover 45,200 to 51,000kJ/hr depending on the water circulation rates of 330 to $690{\ell}$/hr from the waste heat discharged. The exhaust gas temperature left from the heat exchanger dropped to $100^{circ}C$ from $270^{circ}C$ by the heat exchange between the water and the flue gas, while water gained the difference and temperature increased to $38^{circ}C$ from $21^{circ}C$ at the water flow rate of $690{\ell}$/hr. And, the condensed water amount varies from 16 to $43m{\ell}$ at the same water circulation rates. This condensing heat recovery system can reduce boiler fuel consumption amount in a day by 34% according to the feasibility study of the actual mimitomato greenhouse. No combustion load was observed in the hot air heater.

• Korean Institute of Interior Design Journal
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• v.23 no.5
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• pp.76-85
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• 2014

When conscious and unconscious exploring information of space-visitors which is contained in the information acquired in the process of seeing any space is analyzed, it can be found what those visitors pick up as factors in the space for its selection as visual information in order to put it into action. This study, with the object of the space reproduced in three dimensions from the cafe which was visited for conversation, has analyzed the process of acquiring space-information by sex to find out the features of scanning path, findings of which are the followings. First, the rate of scanning type of males was "Combination (50.5%)- Circulation (31.0%) and that of females "Horizontal (32.5%) - Combination (32.1%)", which shows that there was a big difference by sex in the scanning path which took place in the process of observing any space. Second, when the features of continuous observation frequency by sex is looked into, the trends of increased "horizontal" scanning and decreased "Combination" scanning of both showed the same as the frequency of continuous observations increased, while in case of "Circulation" scanning, that of females was found to decrease but that of males showed the aspect of confusion. Third, the 'Combination' scanning of males was found strong at the short observation time with three times of continuous observation frequency defined as "Attention Concentration" while the distinct feature was seen that the scanning type was dispersed to "combination-circulation" as the frequency of continuous observation increased. Females start the information acquirement with "combination-circulation" but in the process of visual appreciation they showed a strong "Horizontal" These scanning features can be defined as those by sex for acquiring space information and therefore are very significant because they are fundamental studies which will enable any customized space-design by sex.