• 대한방사선협회지
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• 제29권1호
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• pp.44-49
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• 2003

감마카메라를 이용하여 영상화할 수 있는 $^{99m}Tc-DMSA$ 신장 검사는 비침습적으로 신장의 기능과 형태를 동시에 평가할 수 있고, 신장 기능의 이상은 형태학적인 변화 보다 먼저 나타나기 때문에 다른 검사보다 $^{99m}Tc-DMSA$ 신장 검사를 이용하면 병변을 조기에 진단할 수 있는 장점이 있다. 신장의 상대적 기능 평가시에 깊이 보정, 총 계수 또는 평균 계수의 사용, BKG 보정, SPECT 검사의

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.469-470
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• 2007

In this paper, we propose a simple and relative electrode contact monitoring method. By exploiting the power line interference, which is regarded as one of the worst noise sources for bio-potential measurement, the relative difference in electrode impedance can be measured without a current or voltage source. Substantial benefits, including no extra circuit components, no degradation of the body potential driving circuit, and no electrical safety problem, can be achieved using this method. Furthermore, this method can be applied to multi-channel isolated bio-potential measurement systems and home health care devices under a steady measuring environment.

• 한국구조물진단유지관리공학회 논문집
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• 제6권1호
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• pp.193-203
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• 2002

The results of an experimental study on Saemangeum dredged sands are presented. Undrained triaxial compression tests were performed with there different initial relative densities, namely 18, 34, and 50%, intend to evaluate undrained Behavior. All undrained triaxial compression tests were performed under static loading conditions. Undrained triaxial compression tests were exhibited complete static liquefaction, zero effective confining pressure and zero stress difference at lower confining pressures. As confining pressures were increased, the effective stress paths indicated increasing resistance to static liquefaction by showing increasing dilatant tendencies. The fines and larger particles create a particle structure with high compressibility at lower confining pressure. The effect of increasing relative density was to increase the resistance of the sand against static liquefaction by making the sand more dilatant.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권1호
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• pp.385-405
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• 2019

High Efficiency Video Coding (HEVC) enables significantly improved compression performance relative to existing standards. However, the advance also requires high computational complexity. To accelerate the intra prediction mode decision, a minimum risk Bayesian classification framework is introduced. The classifier selects a small number of candidate modes to be evaluated by a rate-distortion optimization process using the sum of absolute Hadamard transformed difference (SATD). Moreover, the proposed method provides a loss factor that is a good trade-off model between computational complexity and coding efficiency. Experimental results show that the proposed method achieves a 31.54% average reduction in the encoding run time with a negligible coding loss of 0.93% BD-rate relative to HEVC test model 16.6 for the Intra_Main common test condition.

• 한국영어학회지:영어학
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• 제2권1호
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• pp.97-121
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• 2002

Aoun and Li (1989) and Hornstein (1995) suggest that the cross-linguistic contrast in quantifier scope between English and East Asian languages is attributed to the parametric difference in the base subject position, viz. VP-internal position in English and Spec IP in East Asian languages. This paper argues that their suggestion is untenable, and that the cross linguistic contrast in question is due to the parametric difference that English permits and East Asian languages do not permit (overt) object shift.

• Imaging Science in Dentistry
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• 제34권1호
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• pp.13-18
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• 2004

Purpose : This study was to evaluate the influence of slice thickness of computed tomography (CT) and rapid protyping (RP) type on the accuracy of 3-dimensional medical model. Materials and Methods: Transaxial CT data of human dry skull were taken from multi-detector spiral CT. Slice thickness were 1, 2, 3 and 4 mm respectively. Three-dimensional image model reconstruction using 3-D visualization medical software (V-works /sup TM/ 3.0) and RP model fabrications were followed. 2-RP models were 3D printing (Z402, Z Corp., Burlington, USA) and Stereolithographic Apparatus model. Linear measurements of anatomical landmarks on dry skull, 3-D image model, and 2-RP models were done and compared according to slice thickness and RP model type. Results: There were relative error percentage in absolute value of 0.97, 1.98,3.83 between linear measurements of dry skull and image models of 1, 2, 3 mm slice thickness respectively. There was relative error percentage in absolute value of 0.79 between linear measurements of dry skull and SLA model. There was relative error difference in absolute value of 2.52 between linear measurements of dry skull and 3D printing model. Conclusion: These results indicated that 3-dimensional image model of thin slice thickness and stereolithographic RP model showed relative high accuracy.

• 약학회지
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• 제43권2호
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• pp.278-284
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• 1999

This study deals with the biological changes in mice after ${\gamma}-irradiated$. Four weeks old BALA/c mice were irradiated with 6.5Gy of ${\gamma}-ray$ on the fifth day after oral administration of radioprotectants such as ascorbic acid, tocopherol and cysteine. Control group was irradiated with 6.5Gy without pre-administration of radioprotectors. Blood cells and sperm cells were counted and body, testis and spleen were weighed 3 days after irradiation. And also liver antioxidant activity and range of spleen immune cells were measured. Differences in most biological parameters were not clearly distinguished between experimental groups. However, the relative spleen weight, the relative testis weight and the population size of spleen immune cells such as T helper cells, B cells and macrophages measured by means of FACS showed significant difference between irradiated and radioprotectant administered group. It is concluded that the relative spleen weight, the relative testis weight and the population size of spleen immune cells are easy and useful parameters for assessing the effect of radioprotective substances and for quantifying biological damage of radiation, as well.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.450-455
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• 2001

The time-dependent behavior of nonequilibrium condensation of moist air through the Ludwieg tube is investigated with a computational fluid dynamics(CFD) method. The two-dimensional, compressible, Navier-Stokes equations, fully coupled with the condensate droplet growth equations, are numerically solved by a third-order MUSCL type TVD finite-difference scheme, with a second-order fractional time step. Baldwin-Lomax turbulence model is employed to close the governing equations. The computational results are compared with the previous experiments using the Ludwieg tube with a downstream diaphragm. The results clearly show that for an initial relative humidity below 30% there is no periodic oscillation of the condensation shock wave, but for an initial relative humidity over 40% the periodic excursions of the condensation shock occurs in the Ludwieg tube, and the frequency increases with the initial relative humidity. It is also found that total pressure loss due to nonequilibrium condensation in the Ludwieg tube should not be ignored even for a very low initial relative humidity, and the periodic excursions of the condensation shock wave are responsible for the total pressure loss.

• Journal of Mechanical Science and Technology
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• 제17권12호
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• pp.2066-2077
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• 2003

The time-dependent behavior of unsteady condensation of moist air through the Ludwieg tube is investigated by using a computational fluid dynamics (CFD) work. The two-dimensional, compressible, Navier-Stokes equations, fully coupled with the condensate droplet growth equations, are numerically solved by a third-order MUSCL type TVD finite-difference scheme, with a second-order fractional time step. Baldwin-Lomax turbulence model is employed to close the governing equations. The predicted results are compared with the previous experiments using the Ludwieg tube with a diaphragm downstream. The present computations represent the experimental flows well. The time-dependent unsteady condensation characteristics are discussed based upon the present predicted results. The results obtained clearly show that for an initial relative humidity below 30% there is no periodic oscillation of the condensation shock wave, but for an initial relative humidity over 40% the periodic excursions of the condensation shock occurs in the Ludwieg tube, and the frequency increases with the initial relative humidity. It is also found that total pressure loss due to unsteady condensation in the Ludwieg tube should not be ignored even for a very low initial relative humidity and it results from the periodic excursions of the condensation shock wave.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2001년도 제34회 추계학술대회 개최
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• pp.117-126
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• 2001

Tribological properties of high temperature fade were investigated by changing relative amounts of ingredients in the brake friction material. Based on a simple experimental formulation containing 10 ingredients, friction materials were tested using a pad-on-disk type friction tester. Twenty-five friction material specimens with different relative amounts of the ingredients were manufactured according to the constrained mixture design .The difference ($\Delta$${\mu}$=${\mu}$$\sub$max/. -${\mu}$$\sub$min/. ) of friction coefficients was measured to represent the high temperature fade. Results from elevated temperature tests showed that five ingredients including cashew, graphite, Sb$_2$S$_3$, ZrSiO$_4$, and Cu fibers played important roles on $\Delta$${\mu}$. In order to find relative importance on fade phenomena among these ingredients, ANOVA(analysis of variance) was performed in this investigation. Thirty-two friction material specimens by changing ${\pm}$50vol.％ of these five ingredients were tested to examine the relative importance. Results showed that cashew, graphite '||'&'||' Sb$_2$S$_3$, and cashew '||'&'||' graphite aggravated the fade behavior and Cu fibers improved on fade resistance.