• 지질공학
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• 제13권3호
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• pp.281-292
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• 2003

모형시추공 내에서 공내수 전기전도도의 자동 측정시스템을 구축하고 이로부터 수리상수 결정과 관련된 제반 기초 환경을 검증하였다. 실험은 상대적으로 높은 염도를 공내수로 하고 증류수를 지층수로 사용하여 지층수의 유입과 유출되는 유량을 일정하게 유지한 상태에서 공내수의 전기전도도 프로파일을 구하는 방식으로 이루어졌다. 관찰의 주 대상은 공내수와 지층수 사이의 염도차. 온도차 및 지층수의 유입량. 유입 ·유출구에 따른 모형시추공 내에서의 전기전도도 변화 양상 파악에 있었다. 실헌결과, 이들 요인이 미치는 영향범위와 적정 측정 환경이 제시되어 향후 모델 실험 및 원위치시험에서 적용될 기초실험 여건이 마련되었다.

• 한국가시화정보학회지
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• 제15권1호
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• pp.32-40
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• 2017

Interaction between fluid and a rigid object is frequently observed in everyday life. However, it is difficult to simulate their interaction as the medium and the object have different representations. One of the challenging issues arises especially in handling deformation of the object visually as well as rendering haptic feedback. In this paper, we propose a real-time simulation technique for multimodal interaction between particle-based fluids and soluble solids. We have developed the dissolution behavior model of solids, which is discretized based on the idea of smoothed particle hydrodynamics, and the changes in physical properties accompanying dissolution is immediately reflected to the object. The user is allowed to intervene in the simulation environment anytime by manipulating the solid object, where both visual and haptic feedback are delivered to the user on the fly. For immersive visualization, we also adopt the screen space fluid rendering technique which can balance realism and performance.

• 한국가시화정보학회지
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• 제12권2호
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• pp.23-29
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• 2014

Although many studies have been done on an open-end capillary, the invasion into a closed end capillary is still novel in its investigation. In this research we have explored the fluid invasion in closed-end capillaries where the shape of the meniscus and the height of invasion were accompanied by gas compression inside the capillary. Theoretically, the one dimensional momentum balance equation shows the fluid oscillation. In the experiments, we have found the different phenomena, either the fluid oscillation with low frequency or no oscillation. This discrepancy is mostly caused by two factors. First, a continuous decrease of the advancing contact angle due to decreasing invasion velocity as increasing pressure inside the closed-end capillary reduces the invasion velocities. Second, the high shear stress within the entrance length region was generated by the plug like velocity profile.

• 대한기계학회논문집B
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• 제26권12호
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• pp.1699-1706
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• 2002

In this paper, the investigation about the elevation control and the formation of the free surface of magnetic fluids is carried out theoretically and experimentally on the basis of magnetic fluids is carried out theoretically and experimentally on the basis of Rosensweig' Ferrohydrodynamic Bernoulli Equation. Governing equations of magnetic fields are solved using the concept of vector potential. While applied magnetic fields are induced by 4$\times$4 electromagnet located under the magnetic fluid, the fee surface of the magnetic fluid is formed the balance of surface force, gravity, pressure difference, magnetic normal pressure and magnetic body force. The results of numerical simulation and experiment show the formation of the free surface of the magnetic fluid. Using PID control, an experiment for the elevation control of the free surface of magnetic fluids is performed.

• 대한간호학회지
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• 제25권1호
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• pp.88-98
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• 1995

The Fluid and electrolytes balance in the body is of critical importance in maintaining good health. When the fluid and electrolyte imbalance is present, patients are in great danger. They must be assessed immediately by a nurse so that appropriate treatment can be started as soon as possible. Patients' fluid intake and output records contain highly important information for the diagnosis and treatment of fluid imbalance, but, these records are often inaccurate and the method of recording the fluid intake is not universal for every hospital. Be-cause they are few quantitative measurements of a patient's hydration, the need to improve the accuracy of fluid intake records is very important. However, very few studies have been done to investigate the accuracy of measurements of patients' fluid intake and output. The purpose of this study was to investigate the methods used for calculation of fluid intake which is most similar to fluid output in normal adults and hospitalized patients. This study focused on three different calculation methods for fluid intake and compared these to fluid output and developed suggestions as to the ideal way to record fluid in-take. Data for 43 hospitalized patients and 37 normal adults were analyzed. The findings of this study are as follows ; 1) In normal adults, the daily intake of water which enteres by the oral route was 2415m1 (the first method of calculation). The daily intake of water in the form of pure water or some other beverage was 1365m1 (the third method of calculation) The daily intake of water including fresh fruits and vegetables, rice, porridges, and Me m which have water content more than 80% were 2186m1 (the second method of calculation). 2) The urine output of the normal adults was 1350m1. This apprroximates the amount of fluid an adult takes in the form of pure water. 3) In patient group, the total intake of water was 2550m1 (the first method of calculation). The in-take of water in the form of pure water or as some other beverage and IV fluid was 1661m1 (the third method of calculation). The daily in-take of water including foods which have high water content was 2356m1 (the second method of calculation). 4) The urine output of the patient's group was 1728m1. This approximates the amount of fluid an adult takes in the form of pure water. 5) Investigation of the method of calculation of the patient fluid intake showed that among the 31 hospitals studied, only eight use the third method of calculation which reflects the most close value to urine output. From the results obtained in this study, it was indicated that the amount of fluid taken in the form of pure water reflects the most close value to urine output. Therefore, it can be suggested that the third method of calculation which includes water in-take only in the form of pure water or beverage should be used as patients' fluid intake record.

• 한국농공학회논문집
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• 제56권6호
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• pp.139-147
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• 2014

Forecasting salinity in an estuary reservoir is essential to promise irrigation water for the reclaimed land. The objective of the research was to assess salinity balance and its temporal and spatial variations in the Iwon estuary reservoir which has been issued by its high contents of salinity in spite of desalination process for four years. Seepage flows through the see dikes which could be one of possible reason of high salinity level of the reservoir was calculated based on the salinity balance in the reservoir, and used as input data for salinity modeling. A three-dimensional hydrodynamic model, Environmental Fluid Dynamics Code (EFDC), was used to simulate salinity level in the reservoir. The model was calibrated and validated based on weekly or biweekly observed salinity data from 2006 to 2010 in four different locations in the reservoir. The values of $R^2$, RMSE and RMAE between simulated and observed salinity were calculated as 0.70, 2.16 dS/m, and 1.72 dS/m for calibration period, and 0.89, 1.15 dS/m, and 0.89 dS/m for validation period, respectively, showing that simulation results was generally consistent with the observation data.

• 대한의용생체공학회:의공학회지
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• 제14권4호
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• pp.349-354
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• 1993

To investigate the relations between the physical constitutions, the acid-base balance, and the autonomic nervous function, the blood gas, the heart rate and the concentrations of Na, K of serum were measured pre-and poststimulation. As the result, it is shown that in the normal condition the macro-negative(strong liver- weak lung type) is the metabolic alkalosis, the macro-positive (strong lung-weak liver type) is the metabolic acidosis, the micro-negative(strong kidney-weak spleen type) is the alkalosis and the micro-positive (strong spleen-weak kidney type) is the acidosis. And the ntacro-positive and micro-positive are the sympathetic lead, the macro-negative and micro-negative are the parasympathetic lead. In the macro-positive and micro-positive subjects, the concentration of K in serum is relatively high. This si coincided with the acidosis. But in the macro-negative and micro-negative subjects, the concentration of K in serum is relatively low. This is coincided with the alkalosis.

• Clinical and Experimental Pediatrics
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• 제50권5호
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• pp.430-435
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• 2007

Even though we drink and excrete water without recognition, the amount and the composition of body fluid remain constant everyday. Maintenance of a normal osmolality is under the control of water balance which is regulated by vasopressin despite sodium concentration is the dominant determinant of plasma osmolality. The increased plasma osmolality (hypernatremia) can be normalized by the concentration of urine, which is the other way of gaining free water than drinking water, while the low plasma osmolality (hyponatremia) can be normalized by the dilution of urine which is the only regulated way of free water excretion. On the other hand, volume status depends on the control of sodium balance which is regulated mainly by renin-angiotensin-aldosterone system, through which volume depletion can be restored by enhancing sodium retention and concomitant water reabsorption. This review focuses on the urine concentration and dilution mechanism mediated by vasopressin and the associated disorders; diabetes insipidus and syndrome of inappropriate antidiuretic hormone secretion.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2004년도 추계 학술대회논문집
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• pp.65-68
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• 2004

The design procedure for centrifugal blower with high inlet resistance is not presented yet. Overall fluid dynamic performance is estimated for comparison between the case of atmospheric inlet condition and the present model. Detail information between blades is prepared by using a commercial program, SCRYU-Tetra. A centrifugal blower with large inlet pressure is adopted in an air purifier having filtering devices. As the inlet residence increases the flow rate of the system is decreased. In parallel, outlet area of the system affects the performance of the system in the sense of flow balance. Consequently, the flow balance between the inlet and outlet becomes an important parameter for the design of the scroll casing for the centrifugal blower with high inlet pressure.

• 한국전기전자재료학회논문지
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• 제19권3호
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• pp.260-266
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• 2006

In this paper, We coupled fluid balance and director balance equation from Ericksen-Leslie's continuum theory and observed the motion of Liquid Crystal molecular. We simulated flow velocity and director distribution in which flow effect is considered in switching on and switching off state. We interpreted the dynamic response characteristic caused by the flow. As the result of the simulation, We could see the flow effect. In the case of Twisted Nematic(TN) cell, this flow caused abnormal twist temporarily in switching off state. We could prove that this abnormal twist is a direct cause of optical bounce phenomenon known well until now with the result of simulation. In addition, We analyzed the mechanism of the fast response due to flow in the case of Optically Compensated Bend(OCB) cell.