• Journal of the Korea Society for Simulation
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• v.27 no.1
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• pp.61-73
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• 2018

In the defense modeling and simulation, for the detailed analysis of the communication system, many studies have carried out the analysis under the C3 SoS(system of systems) which consists of C2(command and control) and C(communication). However, it requires time and space constraints of the C2 system. To solve this problem, this paper proposes a communication analysis method in the standalone system environment which is combined with the C system after abstracting the C2 system. In the abstraction process, we hypothesize the traffic model and mobility model for C system analysis and learn the parameters in the model based on machine learning. Through the proposed method, it is possible to construct traffic and mobility model with different output according to the battlefield. This case study shows how the process can be applied to the C3 SoS and the enhanced accuracy than the existing method. We expect that it is possible to carry out the efficient communication analysis against many experimental scenarios with various communication parameters.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.369-376
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• 2003

Coulson (ZINDO), Mulliken $(MP2/6-31G^*)$ and Natural $(MP2/6-31G^*)$ population analyses of several large molecules were performed by the Fragment Reassociation (FR) method. The agreement between the conventional ZINDO (or conventional MP2) and FR-ZINDO (or FR-MP2) charges of these molecules was excellent. The standard deviations of the FR-ZINDO net atomic charges from the conventional ZINDO net atomic charges were 0.0008 for $C_{10}H_{22}$ (32 atoms), 0.0012 for $NH_2-C_{16}O_2H_{28}-COOH$ (53 atoms), 0.0014 for $NH_3^+-C_{16}O_2H_{28}-COOH$ (54 atoms), 0.0017 for $NH_2-C_{16}O_2H_{28}-COO^-$ (52 atoms), 0.0019 for $NH_3^+-C_{16}O_2H_{28}-COO^-$ (53 atoms), 0.0024 for a conjugated model $(O=CH-(CH=CH)_{15}-C=O-(CH=CH)_{12}-CH=CH_2)$, 118 atoms), 0.0038 for aglycoristocetin $(C_{60}N_7O_{19}H_{52}^+$, 138 atoms), 0.0023 for a polypropylene model complexed with a zirconocene catalyst $(C_{68}H-{121}Zr^+$, 190 atoms) and 0.0013 for magainin $(C_{112}N_{29}O_{28}SH_{177}$, 347 atoms), respectively. The standard deviations of the FR-MP2 Mulliken (or Natural) partial atomic charges from the conventional ones were 0.0016 (or 0.0016) for $C_{10}H_{22}$, 0.0019 (or 0.0018) for $NH_2-C_{16}O_2H_{28}-COOH$ and 0.0033 (or 0.0023) for $NH_3^+-C_{16}O_2H_{28}-COO^-$, respectively. These errors were attributed to the shape of molecules, the choice of fragments and the degree of ionic characters of molecules as well as the choice of methods. The CPU time of aglycoristocetin, conjugated model, polypropylene model complexed with zirconocene and magainin computed by the FR-ZINDO method was respectively 2, 4, 6 and 21 times faster than that by the normal ZINDO method. The CPU time of $NH_2-C_{16}O_2H_{28}-COOH\;and\;NH_3^+-C_{16}O_2H_{28}-COO^-$ computed by the FR-MP2 method was, respectively, 6 and 20 times faster than that by the normal MP2 method. The largest molecule calculated by the FR-ZINDO method was B-DNA (766 atoms). These results will enable us to compute atomic charges of huge molecules near future.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.2
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• pp.71-77
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• 1994

A serious of study is carried out to practical use of the three-slot cambered otter board improved by the authors. As the first step, we designed main plates, slots and accessories, such as holding plate, fan-shaped towing plate, normans, center ring, etc. Standing on this design, we made the simple cambered and three-slot cambered model otter board with accessories in a linear scale 6:1. and carried out model test to examine the efficiency of these boards. The obtained results can be summarized as follows: 1. On the simple cambered board with accessories, the values of the maximum shear coefficient($C _{LX}$ ). drag coefficient(($C _{D}$) and hydrodynamic efficiency($C _{L}$/$C _{D}$ ) are 1.39, 0.56, 2.48 at $22^{\circ}$ of the angle of stall respectively. 2. On the three-slot cambered board with accessories, $C _{LX}$/$C _{D}$ and $C _{I}$/$C _{D}$ are 1.67, 0.92, 1.82 at $32^{\circ}$ of the angle of stall respectively. 3.$C _{LX}$ of board with accessories is smaller 10~12% than that of only the main plate, and the angle of stall is almost same. 4. $C _{LX}$ and the angle of stall of the three-slot cambered board with accessories are greater 20% and $10^{\circ}$ than that of the simple cambered board respectively.

• Journal of Energy Engineering
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• v.23 no.1
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• pp.58-66
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• 2014

Catalytic gasification of a low rank coal- Inner Mongolian lignite has been carried out with carbon dioxide. The gasification reactions were performed in a thermogravimetric analyzer at temperatures of $600^{\circ}C$ to $900^{\circ}C$. The kinetic parameters were evaluated using three different gas-solids reaction models and the prediction ability of each model were compared. Among the models evaluated, the modified volumetric model was found to correlate best both the non-catalytic and catalytic gasification reactions. The theoretical models, homogeneous and shrinking-core models, were found to satisfactorily correlate gasification reactions for the non-catalytic and $FeSO_4$-catalyzed reactions. In case of alkali metal catalysts, the catalytic activity was mostly pronounced at a low temperature of $600^{\circ}C$ and observed to decrease by 50% as the temperature was increased to $700^{\circ}C$, and it remained nearly constant at temperature over $800^{\circ}C$. The order of catalytic activity was found to be: $K_2CO_3$ > $Na_2CO_3$ > $K_2SO_4$ > $FeSO_4$.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.7
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• pp.1013-1021
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• 2016

This study developed probabilistic models to predict Salmonella growth in processed meat products formulated with varying concentrations of NaCl and $NaNO_2$. A five-strain mixture of Salmonella was inoculated in nutrient broth supplemented with NaCl (0%, 0.25%, 0.5%, 0.75%, 0.5%, 1.0%, 1.25%, and 1.75%) and $NaNO_2$ (0, 15, 30, 45, 60, 75, 90, 105, and 120 ppm). The inoculated samples were then incubated under aerobic and anaerobic conditions at $4^{\circ}C$, $7^{\circ}C$, $10^{\circ}C$, $12^{\circ}C$, and $15^{\circ}C$ for up to 60 days. Growth (assigned the value of 1) or no growth (assigned the value of 0) for each combination was evaluated by turbidity. These growth response data were analyzed with a logistic regression to evaluate the effect of NaCl and $NaNO_2$ on Salmonella growth. The results from the developed model were compared to the observed data obtained from the frankfurters to evaluate the performance of the model. Results from the developed model showed that a single application of $NaNO_2$ at low concentrations did not inhibit Salmonella growth, whereas NaCl significantly (p<0.05) inhibited Salmonella growth at $10^{\circ}C$, $12^{\circ}C$, and $15^{\circ}C$, regardless of the presence of oxygen. At $4^{\circ}C$ and $7^{\circ}C$, Salmonella growth was not observed in either aerobic or anaerobic conditions. When $NaNO_2$ was combined with NaCl, the probability of Salmonella growth decreased. The validation value confirmed that the performance of the developed model was appropriate. This study indicates that the developed probabilistic models should be useful for describing the combinational effect of $NaNO_2$ and NaCl on inhibiting Salmonella growth in processed meat products.

• Journal of Preventive Medicine and Public Health
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• v.46 no.2
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• pp.74-81
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• 2013

Objectives: The objective of this study was to evaluate the performance of risk-adjusted mortality models for colorectal cancer surgery. Methods: We investigated patients (n=652) who had undergone colorectal cancer surgery (colectomy, colectomy of the rectum and sigmoid colon, total colectomy, total proctectomy) at five teaching hospitals during 2008. Mortality was defined as 30-day or in-hospital surgical mortality. Risk-adjusted mortality models were constructed using claims data (basic model) with the addition of TNM staging (TNM model), physiological data (physiological model), surgical data (surgical model), or all clinical data (composite model). Multiple logistic regression analysis was performed to develop the risk-adjustment models. To compare the performance of the models, both c-statistics using Hanley-McNeil pair-wise testing and the ratio of the observed to the expected mortality within quartiles of mortality risk were evaluated to assess the abilities of discrimination and calibration. Results: The physiological model (c=0.92), surgical model (c=0.92), and composite model (c=0.93) displayed a similar improvement in discrimination, whereas the TNM model (c=0.87) displayed little improvement over the basic model (c=0.86). The discriminatory power of the models did not differ by the Hanley-McNeil test (p>0.05). Within each quartile of mortality, the composite and surgical models displayed an expected mortality ratio close to 1. Conclusions: The addition of clinical data to claims data efficiently enhances the performance of the risk-adjusted postoperative mortality models in colorectal cancer surgery. We recommended that the performance of models should be evaluated through both discrimination and calibration.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.349-354
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• 2004

Predictive growth model of Vibrio parahaemolyticus in modified surimi-based imitation crab broth was investigated. Growth curves of V. parahaemolyticus were obtained by measuring cell concentration in culture broth under different conditions ($Initial\;cell\;level,\;1{\times}10^{2},\;1{\times}10^{3},\;and\;1{\times}10^{4}\;colony\;forming\;unit\;(CFU)/mL$; temperature, 15, 25 37, and $40^{\circ}C$; pH 6, 7, and 8) and applying them to Gompertz model. Microbial growth indicators, maximum specific growth rate (k), lag time (LT), and generation time (GT), were calculated from Gompertz model. Maximum specific growth rate (k) of V. parahaemolyticus increased with increasing temperature, reaching maximum rate at $37^{\circ}C$. LT and GT were also the shortest at $37^{\circ}C$. pH and initial cell number did not influence k, LT, and GT values significantly (p>0.05). Polynomial model, $k=a{\cdot}\exp(-0.5{\cdot}((T-T_{max}/b)^{2}+((pH-pH_{max)/c^{2}))$, and square root model, ${\sqrt{k}\;0.06(T-9.55)[1-\exp(0.07(T-49.98))]$, were developed to express combination effects of temperature and pH under each initial cell number using Gauss-Newton Algorism of Sigma plot 7.0 (SPSS Inc.). Relative coefficients between experimental k and k Predicted by polynomial model were 0.966, 0.979, and 0.965, respectively, at initial cell numbers of $1{\times}10^{2},\;1{\times}10^{3},\;and\;1{\times}10^{4}CFU/mL$, while that between experimental k and k Predicted by square root model was 0.977. Results revealed growth of V. parahaemolyticus was mainly affected by temperature, and square root model showing effect of temperature was more credible than polynomial model for prediction of V. parahaemolyticus growth.

• Journal of Environmental Science International
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• v.8 no.5
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• pp.575-586
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• 1999

From the environmental aspects, primary productivity of phytoplankton plays the most improtant role in enhancement of marine culture oyster production. This study may be divided into two branches; one is estimation of maximum oyster meat production per unit facility(Carrying Capacity) under the present enviromental conditions in Kamak Bay, the other is improvement of carrying from increase of primary productivity by changing the environmental conditions that cause not ot form an unfavorable environment such as the formation of oxygen deficient water mass using the eco-hydrodynamic model. By simulation of three-dimensional hydrdynamic model and ecosystem model, the comparison between observed and computed data showed good agreement. The results of sensitivity analysis showed that phytoplankton maximum growth rate was the most important parameter for phytoplankton and dissolved oxygen. The estimation of mean primary productivity of Wonpo, Kamak, Pyongsa, and Kunnae culture grounds in Kamak Bay during culturing period were 3.73gC/$m^2$/d, 2.12gC/$m^2$/d, 1.98gC/$m^2$/d, and 1.26gC/$m^2$/d, respectively. Under condition not ot form the oxygen deficient water mass, four times increasing of pollutants loading as much as the present loading from river increased mean primary productivity of whole culture grounds to 4.02gC/$m^2$/d. Sediment N, P fluxes that allowed for 35% increasing from the present conditions increased mean primary productivity of whole culture grounds to 3.65gC/$m^2$/d. Finally, ten times increasing of boundary loadings from the present conditions increased mean primary productivity of whole culture grounds to 3.95gC/$m^2$/d. The maximum oyster meat production per year and that of unit facility in actual oyster culture grounds under the present conditions were 6,929ton and 0.93ton, respectively. This 0.93ton/unit facility is considered to be the carrying capacity in study area, and if the primary productivity is increased by changing the environmental conditions, oyster production can be increased.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.7
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• pp.35-44
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• 2004

In this study, a ventilation model was developed to determine a ventilation rate for the balance of heat, moisture and $CO_{2}$ in a mushroom house. Internal and external temperature, relative humidity and $CO_{2}$ concentration were measured and used to validate the ventilation model. The effects of various environmental factors on physiological responses of mushroom were also investigated. The verified model was simulated under the observed ventilation rates with a difference of$ 0.001{\~}0.065\;m^{3}{\cdot}S^{-1}$ (relative error of $0.3{\~}18.9\%$) when external temperature varied 22.5 to $24.8^{circ}C$ and average ventilation rates was $0.35m^{3}{\cdot}S^{-1}$. The optimal conditions for mushroom growth (internal temperature $22 ^{circ}C$, relative humidity $80\%$, $CO_{2}$ concentration 1,000 ppm) were used for the model application with external temperature, relative humidity and $CO_{2}$ concentration of $27.5{\~}33.5^{circ}C$, $60\%$, and 355 ppm, respectively. Thermal balance was a important factor for an optimum ventilation up to the external temperature of $32^{circ}C$, while $CO_{2}$ concentration balance was more important over $32^{circ}C$. This suggests that humidification for moisture balance is required to maintain temperature and $CO_{2}$ concentration at an optimal level by ventilation in a mushroom house.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.4
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• pp.619-626
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• 2010

ROK Joint Chiefs of Staff in developing an WMA-EA(Warfighting Mission Area-Enterprise Architecture) tries to create the practical buildup requirements of military power through precise requirements and operational capabilities based on the architectures. However, it is difficult to verify the effectiveness of target architectures and do efficient requirement planning because we cannot know the gap of quantitative combat effectiveness between current and target WMA-EAs. This study presents an evaluation method of combat effectiveness and focuses on combat's positive effects in WMA-EAs. The method proposed is based on C2 model which is appropriate for the evaluation of combat effectiveness in architectures. We verify the effectiveness of the proposed method through a case study of an anti-ship warfare architecture.