• Journal of the Society of Naval Architects of Korea
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• v.33 no.2
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• pp.30-35
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• 1996

It is well known that the improved methods of the estimation of the service power margin is necessary to design a optimum ship and to operate economically a ship. Unfortunately, most conventional methods of the predicting of the service power margin are not so accurate that attention should be payed to improve this. From this overview, it is importance with. the effects of waves, as recommended by the 15th and 16th International Towing Tank Conference in 1978 and l981. However the progress of research in this field is very slow mainly since it is taken so long time to take data about hull roughness according to ship ages. For instance, it would be taken 17 or 25 years to measure ideally the data for a ship. Moreover it would be also necessary to take data for many types of ships to lead a general solution. A relationship between roughness and ship age are studied in this paper considering full scale data. A comparison is also made between the effects of hull roughness and of weather at sea for the ship.

• Journal of Korean Society of Disaster and Security
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• v.13 no.1
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• pp.1-11
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• 2020

One of the important problem in statistical hydrology is to estimate the appropriated probability distribution for a given sample data. For the problem, a goodness-of-fit test is conducted based on the similarity between estimated probability distribution and assumed theoretical probability distribution. Probability plot correlation coefficient test (PPCC) is one of the goodness-of-fit test method. PPCC has high rejection power and its application is simple. In this study, test statistics of PPCC were derived for generalized extreme value distribution (GEV) models based on L-moments and these statistics were suggested by the multiple and nonlinear regression equations for its usability. To review the rejection power of the newly proposed method in this study, Monte Carlo simulation was performed with other goodness-of-fit tests including the existing PPCC test. The results showed that PPCC-A test which is proposed in this study demonstrated better rejection power than other methods, including the existing PPCC test. It is expected that the new method will be helpful to estimate the appropriate probability distribution model.

• Journal of Plant Biology
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• v.34 no.2
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• pp.93-100
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• 1991

Walnut (Juglans regia L.) is a common cultivated and wild deciduous tree in the temperate regions of Pakistan and elsewhere. A bare or poor understorey of wild or cultivated species is frequently observed beneath and around it. Soil analysis indicated insignificant differences in nutrient status of soils taken from areas with or without walnut influence. Field investigations revealed that the height, shoot, fresh and dry weight of potato, turnip, corn and bean significantly decreased in the walnut-influenced parts of the field compared to their counter-parts in the same field but without walnut influence. Aqueous extracts from various parts, shoot litter, natural rain leachates and soil collected from beneath walnut significantly reduced the germination, early seedling growth, fresh and dry weight, and moisture contents of corn, turnip and bean in various laboratory experiments. Ferulic, p-coumaric, caffeic, vanillic, jJ-hydroxybenzoic, chlorogenic and gallic acid were identified as the possible allelopathic substances in the aquous extracts and rain leachates of the walnut tree. The findings suggest that the observed poor growth of crops is due to allelopathic effects of walnut.walnut.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.107-107
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• 1993

결과 및 고찰: 이 약의 흰쥐에서의 체내동태는 혈중농도로 볼 때 2-exponential pharmacokinetics에 따르고, HPLC법으로 정량한 경우의 $T_1$/$_2$$\alpha$, $T_1$/$_2$$\beta$, AUC, C $L_{T}$, C $L_{R}$, V $D_{SS}$ 는 각각 1.90min, 21.89min, 1899.36$\mu\textrm{g}$ㆍmin/ml, 10.66ml/min/kg, 7.48ml/min/kg, 0.28l/kg으로 bioassay법과는 약간의 차이를 보였다. 분포특성은 간장과 신장에 많이 이행하였으며, 폐로의 이행도 적지만 관찰되었다. 이 약의 단백결합률은 그 농도가 31.3$\mu$M일 때 42.3%였고 water/n-octanol계에서의 유상으로의 분배는 거의 일어나지 않았다. 이 약의 분포용적이 작은 것은 단백결합 때문이라기보다는 높은 극성때문으로 추정되었다. 이 약의 C $L_{R}$은 GFR의 문헌치보다 컸으며 C $L_{T}$의 약 2/3을 차지하므로 약물소실에 있어서 신장의 기여도가 크고 신배설 과정에 신분비가 관여하고 있음을 알 수 있었다. 이런 사실은 CAZ나 CTX등의 기존 세파계 항생제들과 유사했으며, 추후 다회투여시와 용량의존적 체내동태에 관해 더 많은 연구가 필요하리라 생각되었다.되었다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.6
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• pp.561-567
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• 2011

The inverse radiation analysis of a two-dimensional irregular configuration using unstructured triangular meshes is presented. In this study, an enclosure filled with an absorbing, emitting and scattering medium with diffusely emitting and reflecting opaque boundaries is considered. The finite volume method is applied to solve the radiative transfer equation in order to simulate the measured incident radiation values which are used as input data for the inverse analysis. The conjugate gradient method is adopted for the estimation of wall emissivities by minimizing the objective function at each iteration step. To verify the performance of the unstructured grid system, we compare the results with those using a structured grid system for the two-dimensional lopsided shape. The effect of measurement errors on the estimation accuracy is also investigated.

• Microbiology and Biotechnology Letters
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• v.44 no.2
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• pp.163-170
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• 2016

Strains of lactic acid bacteria were isolated from a variety of fermented foods collected in Korea. The strain L2167 showed a strong antipathogenic activity against Bacillus cereus, Listeria monocytogenes, Salmonella Typhimurium, Staphylococcus aureus, and Staphylococcus epidermidis. L2167 was identified as Lactobacillus plantarum by sequence analysis of its 16S rRNA gene. Scanning electron microscopy revealed rough and wrinkled morphology of B. cereus, L. monocytogenes, S. Typhimurium, S. aureus, and S. epidermidis cell membranes after treatment with a crude cell extract of L. plantarum L2167, indicating that Lactobacillus plantarum L2167 might destroy the cell membrane of pathogenic bacteria. The optimal temperature and initial medium pH for Lactobacillus plantarum L2167 growth were 35℃ and 5.5, respectively. Lactobacillus plantarum L2167 was more sensitive to NaCl than Lactobacillus plantarum KCTC21004, used as a control strain. Lactobacillus plantarum L2167 is expected to be developed as a prominent starter strain for efficient inhibition of growth of pathogens.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.4
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• pp.95-104
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• 2010

The storage function model is one of the most commonly used models for flood forecasting and warning system in Korea. This paper studies the physical significance of the storage function model by comparing it with kinematic wave model. The results showed universal applicability of the storage function model to Korean basins. Through a comparison of the basic equations for the models, the storage function model parameters, K, P and $T_l$, are shown to be related with the kinematic wave model parameters, k and p. The analysis showed that P and p are identical and K and $T_l$ can be related to k, basin area, and coefficients of Hack's law. To apply the storage function model throughout the southern part of Korean peninsular, regional parameter relationships for K and $T_l$ were developed for watershed area using data from 17 watersheds and 101 flood events. These relationships combine the kinematic wave parameters with topographic information using Hack's Law.

• Korean Journal of Agricultural Science
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• v.29 no.2
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• pp.53-66
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• 2002

This study was performed to evaluation the consolidation behavior of agricultural reservoir in the very soft ground. The final settlement prediction methods by Terzaghi, Hyperbolic and Asaoka methods were used to compare with the degree of consolidation estimated by exess pore water pressure. The dissipated excess pore water pressure during embankment construction and peak excess pore water pressure on the completed embankment were suggested for the estimation of the degree of consolidation. It was concluded that the degree of consolidation estimated from dissipated excess pore water pressure was more reliable than that from the peak excess pore water pressure. The stability methods for agricultural reservoir was used to compare and analyze with various condition by limit equilibrium method.

• Nuclear Engineering and Technology
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• v.14 no.4
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• pp.172-177
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• 1982

The state of Am in the concentration of 10$^{-5}$M has been studied in the pH range of 5 to 10 by filtration and centrifugation method. By the experiments, we could estimate possible Am hydrolysis products and solubility constants. If the solubility of Am (OH)$_3$ estimated by Baes and Mesmer is increased about a factor of 10, i.e. changing logk=-l8.7 to logk=-17 5 it was found that the calculated curve of Am concentration versus pH agreed completely with experimental values.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.319-323
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• 2001

This study was conducted to derive the regional design rainfall by the regional frequency analysis based on the regionalization of the precipitation. Using the L-moment ratios and Kolmogorov-Smirnov test, the underlying regional probability distribution was identified to be the Generalized extreme value distribution among apt]lied distributions. regional and at-site parameters of the Generalized extreme value distribution were estimated by the method of L-moment. The regional and at-site analysis for the design rainfall were tested by Monte Carlo simulation. Relative root-mean-square error(RRMSE), relative bias(RBIAS) and relative reduction(RR) in RRMSE were computed and compared with those resulting from at-site Monte Carlo simulation. All show that the regional analysis procedure can substantially reduce the RRMSE, RBIAS and RR in RRMSE in the prediction of design rainfall. Consequently, optimal design rainfalls following the regions and consecutive durations were derived by the regional frequency analysis.