• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1933-1938
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• 2004

Nucleate boiling experiments with constant wall temperature of heating surface were performed using R113 for almost saturated pool boiling conditions. A microscale heater array and Wheatstone bridge circuits were used to maintain a constant wall temperature condition and to measure the heat flow rate with high temporal and spatial resolutions. Bubble images during the bubble growth were taken as 5000 frames a sec using a high-speed CCD camera synchronized with the heat flow rate measurements. The geometry of the bubble during growth time could be obtained from the captured bubble images. The bubble growth behavior was analyzed using the new dimensionless parameters for each growth regions to permit comparisons with previous results at the same scale. We found that the new dimensionless parameters can describe the whole growth region as initial and later respectively. The comparisons showed good agreement in the initial and thermal growth regions. The required heat flow rate for the volume change of the observed bubble was estimated to be larger than the instantaneous heat flow rate measured at the wall. Heat, which is different from the instantaneous heat supplied through the heating wall, can be estimated as being transferred through the interface between bubble and liquid even with saturated pool conditions. This phenomenon under a saturated pool condition needs to be analyzed and the data from this study can supply the good experimental data with the precise boundary condition (constant wall temperature).

• Geotechnical Engineering
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• v.14 no.3
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• pp.47-62
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• 1998

The disturbed state concept (DSC) proposed here is based on the idea that a deforming material element can be treated as a mixture of two constituent parts in the relative intact (Rl) and fully adjusted (FA) states, referred to as reference states. Based on this idea, DSC provides a unified constitutive model for the characteristics of saturated sands under cyclic loading. The model parameters for saturated sands are evaluated by using data from truly triaxial test device, The laboratory test results are also used for the verification of D SC model. In general, the model predictions are found to provide satisfactory correlation with the test results. From the results of this research, it can be stated that the DSC model is capable of characterizing the cyclic behavior of saturated sands under dynamic loading.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.1829-1831
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• 2012

Background: The generalized gamma distribution statistics constitute an extensive family that contains nearly all of the most commonly used distributions including the exponential, Weibull and log normal. A saturated version of the model allows covariates having effects through all the parameters of survival time distribution. Accelerated failure-time models assume that only one parameter of the distribution depends on the covariates. Methods: We fitted both the conventional GG model and the saturated form for each of its members including the Weibull and lognormal distribution; and compared them using likelihood ratios. To compare the selected parameter distribution with log logistic distribution which is a famous distribution in survival analysis that is not included in generalized gamma family, we used the Akaike information criterion (AIC; r=l(b)-2p). All models were fitted using data for 369 women age 50 years or more, diagnosed with stage IV breast cancer in BC during 1990-1999 and followed to 2010. Results: In both conventional and saturated parametric models, the lognormal was the best candidate among the GG family members; also, the lognormal fitted better than log-logistic distribution. By the conventional GG model, the variables "surgery", "radiotherapy", "hormone therapy", "erposneg" and interaction between "hormone therapy" and "erposneg" are significant. In the AFT model, we estimated the relative time for these variables. By the saturated GG model, similar significant variables are selected. Estimating the relative times in different percentiles of extended model illustrate the pattern in which the relative survival time change during the time. Conclusions: The advantage of using the generalized gamma distribution is that it facilitates estimating a model with improved fit over the standard Weibull or lognormal distributions. Alternatively, the generalized F family of distributions might be considered, of which the generalized gamma distribution is a member and also includes the commonly used log-logistic distribution.

• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.225-230
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• 2007

A physical model experiment with GPR and 3-D resisitivity survey were conducted to investigate the geoelectrical response of hydrocarbon-impacted zone, so called smeared zone, on the geophysical data. The results from the experiment show that GPR signals were enhanced when LNAPL was present as a residual saturation in the water saturated system (${\varepsilon}_r$ = 21) due to less attenuation of the electromagnetic energy through the medium, compared to when the medium was saturated with only water (${\varepsilon}_r$ = 21). 3-D resistivity data obtained from the former gas station site demonstrate that the highly contaminated zones could be imaged with low resistivities attributed to the biodegradation of petroleum hydrocarbons at the aged, hydrocarbon-impacted sites. The study results also show that the geophysical methods, as a non-invasive sounding technique, can be a very useful tool for mapping hydrocarbon-contaminated zones.

• Computers and Concrete
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• v.13 no.2
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• pp.149-171
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• 2014

This study presents the mathematical model for predicting chloride penetration into saturated concrete under non-isothermal condition. The model considers not only diffusion mechanism but also migration process of chloride ions and other chemical species in concrete pore solution such as sodium, potassium, and hydroxyl ions. The coupled multi-ionic transport in concrete is described by the Nernst-Planck equation associated with electro-neutrality condition. The coupling parameter taken into account the effect of temperature on ion diffusion obtained from available test data is proposed and explicitly incorporated in the governing equations. The coupled transport equations are solved using the finite element method. The numerical results are validated with available experimental data and the comparison shows a good agreement.

• Journal of the Korean Solar Energy Society
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• v.30 no.5
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• pp.93-99
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• 2010

Nucleate pool boiling experiments with constant heat flux condition were performed using pure R113 for various channel heights under saturated pool condition. A circular heater of 1mm diameter, with artificial cavity in the center, fabricated using MEMS technique and the high-speed controller were used to maintain the constant heat flux. Images of bubble growth were taken at 5,000 frames per second using a high-speed CCD camera. The bubble geometry was obtained from the captured bubble images. The effects of channel height on the bubble growth behaviors were analyzed as dimensional scales for the initial and thermal growth regions. The parameters for the bubble growth behaviors were bubble radius, bubble growth rate, and bubble shapes. These phenomena require further analysis for various surface angles, but this study will provide good experimental data with constant heat flux boundary condition for such works.

• Fire Science and Engineering
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• v.16 no.3
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• pp.16-25
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• 2002

For Freon-23, a conventional extinguished agent regulated by Montreal Protocol and HFC-227ea, its alternative, the empirical equations were correlated in terms of saturated pressure, density, viscosity, enthalpy and surface tension. They were obtained by regression analysis from the experimental data in the literature. The empirical equations of saturated pressure were expressed as the second and third order function of temperature. The empirical equation of density was expressed as compressibility factor and saturated pressure by a function of temperature. The empirical equation of viscosity was formulated as a power function. Heat capacities as well as enthalpies were well fitted by empirical form of the second-order temperature. Finally, surface tension simply has linear function form in terms of temperature.

• Journal of the Korean Solar Energy Society
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• v.29 no.4
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• pp.7-14
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• 2009

Nucleate pool boiling experiments with constant heat flux condition were performed using pure R11 and R113 for various surface angles under saturated pool condition. A circular heater of 1 mm diameter, with artificial cavity in the center, fabricated using MEMS technique and the high-speed controller were used to maintain the constant heat flux. Images of bubble growth were taken at 5,000 frames per second using a high-speed CCD camera. The bubble geometry was obtained from the captured bubble images. The effects of surface angles on the bubble growth behaviors were analyzed as dimensional scales for the initial and thermal growth regions. The parameters for the bubble growth behaviors were bubble radius, bubble growth rate, sliding velocity, bubble shape and advancing and receding contact angles. These phenomena require further analysis for various surface angles, but this study will provide good experimental data with constant heat flux boundary condition for such works.

• Fire Science and Engineering
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• v.17 no.1
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• pp.26-32
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• 2003

Inert gases, Af, $N_2$, $CO_2$, as a Halon alternative, the empirical equations were correlated in terms of saturated pressure, density and viscosity, They were obtained by regression analysis from the experimental data in the literature. The empirical equations of saturated pressure were expressed as the second and third order function of temperature. The empirical equation for Ar and $N_2$ of density were expressed as the first order function of temperature. And $CO_2$ was expressed as the second and third order function of temperature. The empirical equation of viscosity was formulated as a power function with temperature. This empirical equations would allow us to predict pure component state.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.170-179
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• 1994

Atherosclerosis, a multifactorial disease, is closely related to lipid nutrition , Data from well known epidemiological studies including Seven Country , Framinghsam Study and several intervention trials have confirmed that serum cholesterol is the major risk factor and elevation of LDL-cholesterol level is most undesriable. On the basis of results concurring in that dietary saturated fat and cholesterol increase serum cholesterol while polyunsaturated fat decrease it, changes in serum choesterol level have been predicted by regression equations developed by Keys et al. and other investigators. Effects of individual fatty acids on the level of serum cholesterol have been further differentiated by chain length, cis-trans isomers and n-6 vs n-3 polyunsaturated fatty acids. Among them the effect of n-3 fatty acids has been well recogniaed as antiplatelet activity, thus reducing the incidence of atherosclerosis. Role of vitamin E in prevention of atherosclerosis has been evovled from works showing that LDL oxdiation stimulates formation of ateroma and also from epidemiologic studies. Dietary recommendations at present are : (ⅰ) 30 and 10 cal % as upper limit of total and saturated fat intakes, respectively (ⅱ) no more than 300 mg cholesterol/day, (ⅲ) 1-2 g of n-3 fatty acid/day and (ⅳ) some increase RDA of vitamin E which is 8-10 TE.