• Journal of Soil and Groundwater Environment
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• v.7 no.4
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• pp.59-67
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• 2002

As a parameter for hydrodynamic modeling to define the range of seawater intrusion, dispersivities are frequently determined from pre-experiments or theoretical studies because field experiments need a lot of time and expenses. If the dispersivities are inadequate for an aquifer, the numerical results may have some errors. We examined the validity of longitudinal dispersivities by comparing the ranges of seawater intrusion with numerical modeling, field data and apparent resistivity sections. In the numerical modeling the TDS distributions simulated by the Xu's longitudinal dispersivity are more similar to the values of TDS measured at monitoring wet]s and boreholes than those by the Neuman's longitudinal dispersivity. The ranges of seawater intrusion by numerical simulations using Xu's longitudinal dispersivity show that the contour line of 1000 ㎎/L. as TDS is located at 480 m from the coast in May, while at 390 m in July. The difference is originated from the shift of the interface between seawater and fresh water. It moved toward the coast in July because of the seasonal increase of hydraulic gradient according to rainfall. A contour line of 15 ohm-m was used to define the range of seawater intrusion in apparent resistivity sections. From this criterion on the interface between seawater and fresh water, the range of seawater intrusion is located at 450 m from the coast. This result is similar to the range of seawater intrusion simulated by the numerical modeling using Xu's dispersivity. Therefore the range of seawater intrusion shows the difference due to the dispersivities used for the hydrodynamic modeling and the dispersivity generated by the Xu's equation is considered more effective to decide the range of seawater intrusion in this study area.

• Korean Journal of Pharmacognosy
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• v.36 no.2 s.141
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• pp.102-108
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• 2005

We have studied the physico-chemical change and pharmacological transformation of traditional herbal medicines with processing. Evodia fruit (EF) has processed for the purpose of detoxification and reduction of its bitter taste. There are various methods of processing EF in Oriental medicinal reference. Among them, we processed EF according to the method of Sang-han theory, the most famous medicinal reference. We processed EF with washing in hot water, and then dried. Processed EFs(PEFs) were prepared according to the above procedure through repetition of 1,3,5 and 7 times respectively. The contents of weight loss, water extract, diluted ethanol extract, ether extract, total ash, acid insoluble ash, alkaloids and limonin in non-processed EF (NPEF) and PEFs were examined. The weight loss, and contents of water extract and dilute ethanol extract in PEF showed decrease in proportion to increase of washing time, while the contents of ether extract, total ash and acid insoluble ash showed little change as compared with those of NPEF. And the content of evodiamine and rutaecarpine was not changed distinctly. However, the content of limonin decreased in the final processed material in proportion to increase of washing times with hot water. And the intense of bitter taste in PEF was also reduced. These results were ascribed to the flowing-out of the water-soluble portion. The biological activities of NPEF and PEF were also investigated. In the test of DPPH scavenging effect, xanthine oxidase inhibition effect and TBA-Rs effect, PEF was more effective than NPEF in vitro. Also, both NPEF and PEF showed potent analgesic and anti-inflammatory effects against in mice. Especially, PEF by 3 times washing with hot water was more effective than other PEFs. From these results, it is considered that PEF should be prepared by 3 times washing with hot water.

• Journal of Korean Society of Transportation
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• v.23 no.3 s.81
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• pp.7-19
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• 2005

Mode choice Analysis is essential analysis stage in transportation demand forecasting process. Therefore, methods for calibration and forecasting of mode choice model in aspect of practical view need to be discussed in depth. Since 1980s, choice models, especially Logit model, are spread widely and rapidly over academic area, research institutes and consulting firms in Korea like other developed countries in the world. However, the process of calibration and parameter estimation for practical application was not clearly explained in previous papers and reports. This study tried to explain clearly the calibration process of mode choice step by step and suggested a forecasting mode choice model that can be applicable in real policy analysis by using household survey data of Pusan metropolitan are. The study also suggested a way of estimating attributes which was not observed during the household survey commonly such as travel time and cost of unchosen alternative modes. The study summarized the statistical results of model specification for four different Logit models as a process to upgrade model capability of explanation for real traveler's choice behaviors. By using the analysis results, it also calculated the value of travel time and compared them with the values of other previous studies to test reliability of the estimated model.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.219-225
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• 1993

The evaluation of radiation-induced DNA double strand breaks (DSB) was made following irradiation of human lymphocytes, murine lymphocytes and EL-4 leukemia cells over a wide dose range of $^{60}Co\;{gamma}-rays.$ In lipopolysaccharide (LPS) or phytohemagglutinin (PHA)-stimulated murine lymphocytes, the slopes of the stand scission factor (SSF) revealed that lymphocytes with LPS increased DNA DSB formation by a factor of 1.432 (p<0.005). Furthermore, strand break production was relatively inefficient in the T lymphocytes compared to the B lymuhocytes. And EL-4 leukemia cells were found to form significantly more DNA DSB to a greater extent than normal lymphocytes (p<0.005). The in vitro studies of the intrinsic radiosensitivity between human lymphocytes and murine lymphocytes showed similar phasic kinetics. However, murine lymphocytes were lower in DNA DSB formation and higher in the relative radiation dose of 10 percent DNA strand breaks at 3.5 hours following ${gamma}-irradiation$ than human lymphocytes. Though it is difficult to interpret these results, these differences may be result from environmental and genetic factors. From our data, if complementary explanations for this difference will be proposed, the differences in the dose-effect relationship for the induction of DSB between humans and mice must be related to interspecies variations in the physiological condition of the peripheral blood in vitro and not to differences in the intrinsic radiation sensitivity of the lymphocytes. These results can be estimated on the basis of dose-effect correlation enabling the interpretation of clinical response and the radiobiological parameters of cytometrical assessment.

• Journal of Food Hygiene and Safety
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• v.5 no.1
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• pp.7-12
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• 1990

The disposition of Brazilin including plasma concentration-time profiles, excretions via urine and bile, and plasma protein binding was investigated after intravenous or oral administration of radio labeled Brazilin ($^3H-Brazilin$) to male Wistar rats. The main pharmac:okinetic parameters were as follows; $t\;_{ 1/2}$, 13.71 hr; AUC, $53.38\;\mu\textrm{g}{\cdot}hr/ml$; AUMC, $1013.4I\;\mu\textrm{g}{\cdot}hr^2/ml$, MRT, 18.95 hr; Vss, 17778 mllkg and CL, 936.77 ml/hr.kg. The 2nd peak was found in the plasma concentration-time profiles indicating potential enterohepatic circulation. The enterohepatic circulation was supported by the bile excretion. After oral administration, about 64.4 % of administered radioactivity was excreted into the bile within 10 hours and its excretion rate reached maximum at 3 hours after administration. The Vss was extremely high, 17.8 l/kg indicating distribution of brazilin in most organs (tissues) with high concentration of brazilin in some organs. Brazilin was distributed into most of organs (spleen, adrenal, pancreas, kidney, thymus, lung, heart, liver, prostate, epididymus, testis, fat, muscle and done) except brain. High concentration of Brazilin was detected especially in liver, kidney, epididymus and testis. Approximately, 62.9% and 44.1% of the dose was excreted for intravenous and oral administration, respectively. About 80% of the dose eventually excreted into urine was excreted within 24 hr after dosing. Plasma protein binding of brazilin resulted in $40\;{\pm}\;4%$ by ultrafiltration method.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.4
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• pp.247-259
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• 2007

In this study, we examined the flux of carbon and water using an eco-hydrological model, Regional Hydro-Ecologic Simulation System (RHESSys). Our purposes were to develop a set of parameters optimized for a well-designed experimental watershed (Gwangneung Research Watershed, GN) and then, to test suitability of the parameters for predicting carbon and water fluxes of other watershed with different regimes of climate, topography, and vegetation structure (i.e Gangseonry Watershed in Mt. Jumbong, GS). Field datasets of stream flow, soil water content (SWC), and wood biomass product (WBP) were utilized for model parameterization and validation. After laborious parameterization processes, RHESSys was validated with the field observations from the GN watershed. The parameter set identified at the GN watershed was then applied to the GS watershed in Mt. Jumbong, which resulted in good agreement for SWC but poor predictability for WBP. Our study showed that RHESSys simulated reliable SWC at the GS by adjusting site-specific porosity only. In contrast, vegetation productivity would require more rigorous site-specific parameterization and hence, further study is necessary to identify primary field ecophysiological variables for enhancing model parameterization and application to multiple watersheds.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.140-146
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• 2017

It is laser induced breakdown spectroscopy(LIBS) that enables qualitative and quantitative analysis of the elements contained in unknown specimen by comparing the wavelength characteristics of each element obtained from the spectral analysis of the standard specimen with the wavelength analysis results from unknown specimens. In this study, the applicability of LIBS to the analysis of major deterioration factors affecting concrete durability was experimentally analyzed. That is, the possibility of applying LIBS to the diagnosis of concrete deterioration by studying the quantitative detection of harmful deteriorating factors on chloride, sulfate and carbonated mortar specimens using LIBS was studied. As a result of LIBS test for each chloride and sulfate specimen, the LIBS spectral wavelength intensity of chlorine and sulfur ions increased linearly with increasing concentration. Carbon ion LIBS spectral wave intensities of carbonated specimens increased nonlinearly over the duration of carbonation exposure. From the above results, it can be partially confirmed that LIBS can be applied to the diagnosis of concrete deterioration. In case of concrete carbonation, it is presumed that carbon content is contained in the cement itself and is different from the detection of chloride and sulfate specimen. Therefore, it is considered that more various parameter studies should be performed to apply LIBS to concrete carbonation.

• Journal of KIISE:Software and Applications
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• v.33 no.2
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• pp.201-219
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• 2006

The key to developing software with the lowest cost and highest quality is to implement or fit the software development process into a given environment. Generally, applying commercial or standard software development processes on a specific project can cause too much overhead if there is no effort to customize the given generic processes. Even though the customizing activities are done before starting the project, these activities are thoroughly dependent on the process engineers who have abundant experience and knowledge with tailoring processes. Owing to this dependence on human knowledge, it has been very difficult to explain the rationale for the results of process tailoring and it takes a long time to get the customized process that is applicable. Hence, we suggest a process tailoring method which adopts the artificial neural network based teaming theory to reduce the time consumed by process tailoring. Furthermore, we suggest the feedback loop mechanism to get higher accuracy in the neural network designed for the process tailoring. It can be done by reusing the process tailoring data results and determining its appropriateness level as sample data to the neural network. We proved the effectiveness of our process tailoring method through case studies using real historical data, which yielded abundant process tailoring results as sample data.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.28-32
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• 2003

As part of studies on the high quality dunggule tea, made of Polygonatum odoratum root with different growth year were analyzed for their flavor compounds. The quality attributes related to flavors were compared between raw and roasted samples which were treated at $130^{\circ}C$ for 15 min. Free sugars in the roots were mainly composed of fructose ($3.59{\sim}4.83%,\;d.b.$), sucrose ($1.78{\sim}2.49%$), and glucose ($1.60{\sim}1.80%$). Threonine ($1,239{\sim}1,444\;mg/100g,\;d.b.$), arginine ($589{\sim}689$), histidine ($289{\sim}370$) were three major free amino acids. The root grown for three years showed the highest content in total free sugar and amino acids (p<0.05). There was negligible difference in proximate composition and Hunter's color parameter depending on the growth year of the roots. However, sensory scores on color, taste and aroma were highest in 3 years' root, which is found most suitable for the preparation of dunggule tea. The roasting of 3 years old root significantly reduced the content of fructose and sucrose (p<0.01). It caused most apparent changes in the decreasing amount of threonine and in the decreasing rate of lysine, showing the significant decrease in total free amino acid content (p<0.01).

• Journal of The Korean Astronomical Society
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• v.37 no.4
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• pp.199-203
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• 2004

The gas response to a proposed spiral stellar pattern for our Galaxy is presented here as calculated via 2D hydrodynamic calculations utilizing the ZEUS code in the disk plane. The locus is that found by Drimmel (2000) from emission profiles in the K band and at 240 ${\mu}m$. The self-consistency of the stellar spiral pattern was studied in previous work (see Martos et al. 2004). It is a sensitive function of the pattern rotation speed, $\Omega$p, among other parameters which include the mass in the spiral and its pitch angle. Here we further discuss the complex gaseous response found there for plausible values of $\Omega$p in our Galaxy, and argue that its value must be close to $20 km s^{-l}\;kpc^{-1}$ from the strong self-consistency criterion and other recent, independent studies which depend on such parameter. However, other values of $\Omega$p that have been used in the literature are explored to study the gas response to the stellar (K band) 2-armed pattern. For our best fit values, the gaseous response to the 2-armed pattern displayed in the K band is a four-armed pattern with complex features in the interarm regions. This response resembles the optical arms observed in the Milky Way and other galaxies with the smooth underlying two-armed pattern of the old stellar disk populations in our interpretation. The complex gaseous response appears to be related to resonances in stellar orbits. Among them, the 4:1 resonance is paramount for the axisymmetric Galactic model employed, and the set of parameters explored. In the regime seemingly proper to our Galaxy, the spiral forcing appears to be marginally strong in the sense that the 4:1 resonance terminates the stellar pattern, despite its relatively low amplitude. In current work underway, the response for low values of $\Omega$p tends to remove most of the rich structure found for the optimal self-consistent model and the gaseous pattern is ring-like. For higher values than the optimal, more features and a multi-arm structure appears.