• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.95-100
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• 1992

The radioisotopic measurement of glomerular filtration rate (GFR) has required analysis of serial blood or urine samples over several hours, and does not allow measurement of separate renal function unless separate catherterization of individual ureters is done. Gates described isotopic method for the measurement of global and unilateral GFR based on the determination by scintillation camera of the fraction of the injected dose of $^{99m}Tc-diethylenetriaminepentaacetic$ acid (DTPA) present in the kidneys 2-3 minutes after its administration. We calculated GFR according to Gates' method in 58 adult patients with various levels of global renal function using $^{99m}Tc$ DTPA and validated this technique by correlation with 24 hour creatinine clearance. A good correlation was observed between 24 hour creatinine clearance and GFR calculated by Gates' formula, with an r value of 0.91 (p<0.01). We concluded that determination of GFR according to the Gates' formula allows good and reproducible prediction of GFR with great rapidity and simplicity rendering this technique suitable for clinical practice.

• Ocean and Polar Research
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• v.32 no.1
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• pp.23-40
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• 2010

This study investigated the effects of imported fisheries products on WTO/DDA tariff negotiations. To calculate the results, the study estimated the demand functions of imported fisheries products by using unit root and cointegration approaches. These approaches allowed us to solve spurious regression problems with macro-economic variables. In addition, this study surmised the effects of change by individually imported fish products from a tariff negotiation model using price elasticities of estimated import demand function. In a process of the analysis for estimating import effects, this study found out that 39 out of 128 imported fish products had positive (+) price elasticities or did not exhibit cointegrations. To cure this problem, this study suggested that the effects of these 39 imported products be estimated with the average variation rate of import volume, rather than by the Ordinary Least Squares approach. In this study, a case-study of tariff formula with coefficient 8 based on a 'Swiss formula' for priority duty rate of 2001 and 2008 was used by to analyze the effect of change in the 128 imported fish products of both years, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.11
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• pp.1499-1507
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• 2000

This trial was to compare the digestive function of laboratory animals, which included omnivores (rats) and herbivores (rabbits, guinea pigs and hamsters). Ten weanling rats, rabbits, guinea pigs and hamster were randomly allocated in individual metabolic cages for a performance and a digestibility trial. Results showed that guinea pigs were significantly best in digestion of dietary crude protein and fiber. Rabbits, however, had the poorest nutrient digestion among the herbivores. Crude fiber digested significantly less by rats than by the herbivores (p<0.05). The digesta retention in the GI tract was longest in rabbits followed by guinea pigs, rats and hamsters. The relative length of the large intestine was significantly shorter in rats as compared to guinea pigs or hamsters. Both the weight and length ratio of the caecum or colon-rectum to the large intestine reflected the major site for fermentation that was the caecum in rabbits and the colon-rectum in guinea pigs. 10% of crude fiber diet did not result in damaged mucosa in any of the experimental animals in this trial.

• Journal of Pharmaceutical Investigation
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• v.20 no.1
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• pp.19-28
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• 1990

Pharmacokinetic parameters of aminoglycosides are dependent on renal function, sex, age, hematocrit, fever, lean body weight (LBW) and disease states, etc. Therefore, the individual pharmacokinetic parameters such as half life $(t^{1/2})$ and volume of distribution(Vd) are needed to achieve optimal therapy. However these parameters had not been determined in Koreans. The purpose of this study was to evaluate the Vd and $t^{1/2}$ of amikacin in Korean patients who had normal renal function, to compare the mean values of study group with that reported in the literature and to compare the measured $t^{1/2}$ with the expected $t^{1/2}$ based on actual body weight (ABW), LBW and ideal body weight (IBW), respectively. Based on data, the Vd was greater than the literature and $t^{1/2}$ was similar to the literature. The predicted $t^{1/2}$ based on IBW was the closest to actual $t^{1/2}$. And postpartum patients had greater Vd than other group and had lower correlation between actual elimination rate constant and calculated creatinine clearance but higher correlation between actual elimination rate constant and Vd than other group.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.4
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• pp.125-136
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• 1996

In order to investigate the characteristics of gravity drainage for geotextile, small-scale model tests for the geotextile chimney drain of earth dam which is a typical type of gravity drainage were carried out using 15 kinds of nonwoven and composite geotextiles. According to the results of this study, the drainage discharge of geotexgile drain generally increases with exponential function as hydraulic head increases and the increasing rate is greater in the coarser soil of dam material. It has a trend to increase when the construction slope of geotextile drain is steeper and the number of layers of geotextile is more. The relationship between the transmissivity of geotextile and the drainage discharge has positive correlation and the rate of increase is greater in the coarser soil. The geotextile products must be carefully selected in consideration of transmissivity of geotextile when the soil to be drained is coarser and the seepage flow is relatively high. Most of staple fiber nonwoven geotextile used in this study are found to be appropriate for drainage purpose. Among them, the composite geotextile the type of which geotextile is evaluated to be the most excellent material. But the geotextile of low permeability such as filament thermal bonded and filament spunbonded nowovens closely examined their transmissivity especially to be used for drainage function.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.130-134
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• 2007

DCF(Distributed Coordination Function) of IEEE 802.11 WLAN(Wireless Local Area Network) MAC Layer apply to CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance) for solution of collision when the station try to access at the same time. But DCF happens falling performance as increasing a number of stations. In this paper, we suggest algorithm that improved performance in congestion. And we compare DCF, DCF+ and proposed algorithm respect to saturation throughput, delay, collision rate and drop rate using NS2(Network Simulator 2) simulation tool.

• Membrane Journal
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• v.14 no.2
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• pp.142-148
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• 2004

This paper presents the enhancement of oxygen transfer efficiency using vibrating intravascular lung assist device (VIVLAD) for patients having chronic respiratory problems. The flow rate was controlled by the pump and monitored by a built-in flow meter. The vibration apparatus was composed of a piezo-actuator, a function generator, and a power amplifier. Gas flow rates of up to 6 L/min through the 120-cm-long hollow fibers have been achieved by exciting a piezo-actuator. The output PVDF sensor and FRF (frequency response function) were investigated by various frequency in VIVLAD. As a result, the maximum oxygen transfer rate was found to occur with maximum amplitude and the transfer of vibration to the hollow fiber membranes. It was excited by the frequency band of 35 Hz at various distilled water flow rates, and various module types.

• The Journal of the Acoustical Society of Korea
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• v.11 no.2
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• pp.5-14
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• 1992

In the fields of astronomy, communication, X-ray crystallography, and engineering, it is a very important and useful fact that the original signal can be reconstructed from a partial information, only spectral magnitude or phase, of the signal. In this paper, we proposed a modified iterative algorithm to solve the Magnitude Retrieval Problem (MRP) for 1-D, 2-D signals. In oder to accelerate the convergence rate, the unit constant initial function which is used in the references is replaced by the exponential initial function for the modified adaptive iterative method. As a result, MRP with 1-D signal and low-pass detail image is significantly enhanced from an iterative convergence rate and a computer storage memory points of view.

• International Commerce and Information Review
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• v.8 no.3
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• pp.71-95
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• 2006

In recent, T-commerce is widely dispersed as alternative type of commerce. It is forecasted that t-commerce system is used more than e-commerce system. Therefore more and more t-commerce-related industries are also recognizing that t-commerce is a critical business model. It is needed to understand the concept of t-commerce and develop the t-commerce marketing strategy. CEO analyses consumer's behaviors according to the data about buyers and applies the advantage of t-commerce to the communication with customers. This t-commerce system plays an important role in maximizing customer satisfaction and affecting their intention to reuse it. Therefore this paper attempts to identify T-commerce critical success factors and divide between use-intention group and unuse-intention group by taking out a discriminant function by the discriminant analysis. This lays a foundation in developing T-commerce strategy. According to the discriminant function extracted, convenience factor, amusement factor, system quality factor, product perception factor are significant in the sequence of influential degree. However, usefulness factor and speedy connection factor are not significant. In result, the target hitting rate is 77.9% in the first unuse-intention group and it is 95.2% in the second use-intention group. The total discriminant target hitting rate is computed to higher value, 86.55%. The statistic package, SPSS 12.0, is used to survey and analyse data and test the hypothesis. The validity and reliability of variables are verified by both reliability analysis and factor analysis. The discriminant analysis is used to tell the difference between use-intention group and unuse-intention group.

• YAKHAK HOEJI
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• v.34 no.2
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• pp.88-101
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• 1990

Captopril, angiotensin converting enzyme (ACE) inhibitor, when given intravenously in dog, elicited the diuretic action along with the increases of glomerular filtration rates (GFR), renal plasma flow (RPF) and osmolar clearances (Cosm) with no changes of free water clearnces ($C_{H_2O}$), and then captopril produced the enlargement of excretion rates of electrolytes in urine and the reduction of reabsorption rates of electrolytes in renal tubles. Captopril, when given into a renal artery, exhibited no changes of renal function in the experinental kidney, whereas diuretic action with the same mechanism as shown in intravenous captopril in control kidney. Captopril, when injected into a carotid artery, showed increases in rates of urine flow in a small does which did not affect on renal action when it was administered intravenusly. Diuretic action induced by captopril was not influenced by renal artery denervation, propranolol and angiotensin II inhibiters. Above results suggest that captopril produced diuretic action along with renal hemodynamic changes by slight contraction of vas efferense and reduction of reabsorption rate of electrolytes in renal tubules, especilly distal tubules, that may be mediatedby endogenous substances.