• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.4
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• pp.329-335
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• 2013

Three-dimensional quantitative structure-activity relationships (3D-QSARs) models between the substituents with changing groups ($R_1$ & $R_2$) of 4-hydroxybenzyl alcohol (4-HBA) derivatives as substrate molecule and their inhibitory activities against tyrosinase were derived and discussed quantitatively. The optimized CoMSIA FF model showed the best predictability and fitness ($r^2$ = 0.858 & $q^2$ = 0.951). The contour maps of the optimized CoMSIA FF model showed that, the inhibitory activities of the analogues against tyrosinase were expected to increase when hydrophobic (Hy) favor, negative charge (E) favor, steric (S) disfavor and hydrogen bond donor (HD) disfavor groups were substituted at the $R_2$ position. When the hydrogen bond donor (HD) favor groups were substituted at the $R_1$ position, it is predicted that the substituents will be able to increase the inhibitory activity.

• Journal of Ginseng Research
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• v.42 no.4
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• pp.419-428
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• 2018

Background: Despite the large number of studies on ginseng, pharmacological activities of ginseng seed oil (GSO) have not been established. GSO is rich in unsaturated fatty acids, mostly oleic and linoleic acids. Unsaturated fatty acids are known to exert a therapeutic effect in nonalcoholic fatty liver disease (NAFLD). In this study, we investigated the protective effect and underlying mechanisms of GSO against NAFLD using in vitro and in vivo models. Methods: In vitro lipid accumulation was induced by free fatty acid mixture in HepG2 cells and by 3 wk of high fat diet (HFD)-feeding in Sprague-Dawley rats prior to hepatocyte isolation. The effects of GSO against diet-induced hepatic steatosis were further examined in C57BL/6J mice fed a HFD for 12 wk. Results: Oil Red O staining and intracellular triglyceride levels showed marked accumulation of lipid droplets in both HepG2 cells and rat hepatocytes, and these were attenuated by GSO treatment. In HFD-fed mice, GSO improved HFD-induced dyslipidemia and hepatic insulin resistance. Increased hepatic lipid contents were observed in HFD-fed mice and it was lowered in GSO (500 mg/kg)-treated mice by 26.4% which was evident in histological analysis. Pathway analysis of hepatic global gene expression indicated that GSO increased the expression of genes associated with ${\beta}$-oxidation (Ppara, Ppargc1a, Sirt1, and Cpt1a) and decreased the expression of lipogenic genes (Srebf1 and Mlxipl), and these were confirmed with reverse transcription and quantitative polymerase-chain reaction. Conclusion: These findings suggest that GSO has a beneficial effect on NAFLD through the suppression of lipogenesis and stimulation of fatty acid degradation pathway.

• Korean Journal of Computational Design and Engineering
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• v.19 no.4
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• pp.305-315
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• 2014

It is important to predict and measure the combat effectiveness (CE) of weapons system in battlefield for acquiring efficient weapon system. Moreover, quantitative calculation of weapon effectiveness under complicated and uncertain battlefield environment is also difficult based on the future network centric warfare. Many papers used the term of combat effectiveness and tried to study a lot of related issues about it. However, there is no paper dealing with the classification of study issue about CE and what will happen in this study field. In this paper, we proposed how to classify the study issue about CE and forecast future direction of this study field. Conceptually, CE is nothing but the assessment results to measure the ability of a military weapon system to accomplish its objective. We believe that it is an appropriate time to review the literature extensively on CE analysis because the research interests and the papers of CE are rapidly growing in these days. This paper reviewed many CE analysis papers, classified them according to their research content and the research methodology applied. Additionally, a comprehensive list of future research areas is also given.

• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.220-227
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• 2020

Purpose: This study aims to investigate the cusp variation pattern of the Korean mandibular second premolar and to determine the difference in tooth diameter and surface area using a virtual three-dimensional model. Methods: Dental casts from 69 students were scanned as a virtual dental models with a three-dimensional dental model scanner. Tooth diameter, absolute and relative individual areas, total crown area, the number of lingual cusps and central groove pattern were analyzed using RapidForm 2004. The Mann-Whitney U-test and the Kruskal-Wallis test were performed to verify sexual dimorphism, the difference in tooth diameter and surface according to the cusp variation pattern (α=0.05). Results: There was no significant difference except in buccolingual diameter (p<0.05) and buccolingual diameter at the cervix (p<0.05). The relative surface area of the total clinical crown was 65.76% for the buccal half and 34.24% for the lingual half, with a ratio of 2:1. In the case of the presence of two lingual cusps, the ratio was 21.47% for the mesiolingual half and 14.12% for the distaolingual half, with a ratio of 3:2. The dominant central groove patterns of the second premolar were the H-pattern (42.0%), followed by the Y-pattern (37.7%), then the U-pattern (20.3%). The relative buccal half was largest in the U-pattern central groove and the relative lingual half was largest in the Y-pattern central groove (p<0.05). Conclusion: This study is significant in that it measured quantitative surface areas and the findings could be a meaningful reference to comprehend dental anatomy in Koreans.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.227-239
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• 2006

Reliability prediction provides a rational basis for design decisions such as the choice between alternative concepts, choice of part quality levels, derating factors to be applied, use of proven versus state-of-the-art techniques, and other factors. For this reasons, reliability prediction is essential functions in developing space systems. The worth of the quantitative expression lies in the information conveyed with the numerical value and the use which is made of that information and reliability prediction should be initiated early in the configuration definition stage to aid in the evaluation of the design and to provide a basis for item reliability allocation (apportionment) and establishing corrective action priorities. Reliability models and predictions are updated when there is a significant change in the item design availability of design details, environmental requirements, stress data, failure rate data, or service use profile. In this paper, the procedure, selection of reliability data and methods for space system reliability prediction is presented.

• Journal of Digital Contents Society
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• v.11 no.4
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• pp.463-471
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• 2010

In the management of a wastewater treatment plant which is a combination system of physical, chemical, and biological processes, computer simulator is an indispensable part for analysis of the operation status and evaluation of the treatment performance due to its fast computing speed. As an application software carrying out the data input-output operations and the mathematical calculations of the models, simulator is to be a powerful tool for estimating the treatment reaction and calculating mass balance of substrates, microorganisms, and chemicals within the treatment system in a given condition. Qualitative and quantitative prediction of treatment performance provides the plant manager with validity of decision-making through implementing modeling and simulation as a role of knowledge-based expert system in charge of automation and control. This paper shows the proceeding of design and development of the "WEC-Sim" software which is owned the various functions of data acquisition, monitoring, simulation, and control.

• Earthquakes and Structures
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• v.14 no.6
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• pp.577-587
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• 2018

The quantitative assessment of the seismic collapse risk of a structure requires the usage of an optimal intensity measure (IM) which can adequately characterise the severity of the ground motion. Research suggests that the average spectral acceleration ($Sa_{avg}$) may be an efficient and sufficient alternate IM as compared to the more traditional first mode spectral acceleration, $Sa(T_1)$, particularly during seismic collapse risk estimation. This study primarily presents a comparative evaluation of the sufficiency of the average spectral acceleration with respect to ground motion duration, and secondarily assesses the impact of ground motion duration on collapse risk estimation. By assembling a suite of 100 historical ground motions, incremental dynamic analysis of 60 different inelastic single-degree-of-freedom (SDF) oscillators with varying periods and ductility capacities were analysed, and collapse risk estimates obtained. Linear regression models are used to comparatively quantify the sufficiency of $Sa_{avg}$ and $Sa(T_1)$ using four significant duration metrics. Results suggests that an improved sufficiency may exist for $Sa_{avg}$ when the period of the SDF system increases, particularly beyond 0.5, as compare to $Sa(T_1)$. In reference to the ground motion duration measures, results indicated that the sufficiency of $Sa_{avg}$ is more sensitive to significant duration definitions that consider almost the full wave train of an accelerogram ($SD_{a5-95}$ and $SD_{v5-95}$). In order to obtain a reduced variability of the collapse risk estimate, the 5-95% significant duration metric defined using the Arias integral ($SD_{a5-95}$) should be used for seismic collapse risk estimation in conjunction with $Sa_{avg}$.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.286-291
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• 2008

Insulation of refrigerator with gasket material near door becomes the technical point at the aspect of heat loss and energy efficiency. Heat loss of refrigerator through the gasket is nearly 30%. In this paper, quantitative evaluation method of heat loss through gasket in established suggest the method for the improvement of heat loss. To analyze the heat transfer, we have used the common software Fluent that is used to CFD. Because of using the convection coefficient of heat transfer, we have solved only the equation of energy for heat transfer. As a result, we have known that heat loss flows through the heat flux vector and that the heat gathered out of the outside iron plate is transferred inner part through the gasket and ABS, etc. Through the result of the numerical simulation that use sub-gasket, we have known that we are able to reduce the heat loss about $20{\sim}40%$. when we applied that sub-gasket on a real refrigerator, the power consumption had reduced about 4.76%. In addition, when we applied a more improved sub-gasket on a real refrigerator and measured the power of the refrigerator the power consumption does reduce about 3% and we will try to apply the improved sub-gasket on a new models of refrigerator.

• Journal of the Optical Society of Korea
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• v.19 no.2
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• pp.136-143
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• 2015

Image deblurring by a deconvolution method requires accurate knowledge of the blur kernel. Existing point spread function (PSF) models in the literature corresponding to lens aberrations and defocus are either parameterized and spatially invariant or spatially varying but discretely defined. In this paper, a parameterized model is developed and presented for a PSF which is spatially varying due to lens aberrations and defocus in an imaging system. The model is established from the Seidel third-order aberration coefficient and the Hu moment. A skew normal Gauss model is selected for parameterized PSF geometry structure. The accuracy of the model is demonstrated with simulations and measurements for a defocused infrared camera and a single spherical lens digital camera. Compared with optical software Code V, the visual results of two optical systems validate our analysis and proposed method in size, shape and direction. Quantitative evaluation results reveal the excellent accuracy of the blur kernel model.

• Journal of the Ergonomics Society of Korea
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• v.25 no.3
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• pp.49-60
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• 2006

Technological encroachment provides human operators with flood of information that must be analyzed to understand the environment and make judgments that lead to strategic actions. Further, the environment is not static and therefore uncertain, changing its aspect dynamically. Complexity accompanied with its dynamics imposes substantial difficulty to human operators' task. Criticality of having situational understanding becomes more important than ever. Situationalunderstanding requires the human operators possessing tacit knowledge in order for them to make the sense out of the situation while interacting with information from many heterogeneous sources, the notion of sensemaking. Sensemaking refers to the process of developing mental framework to assemble pieces of information representing different aspects of the environment that can be used to develop one's own actionable knowledge to implement their judgments in the uncertain environment. Therefore, judgment process and performance is a key component of sensemaking process. Among many judgment and decision making models, the lens model with its extension can be utilized to partially describe the judgmental aspect of sensemaking. One of the lens model parameters, unmodeled knowledge, can be a corresponding quantitative measure for the tacit knowledge that plays an important role in sensemaking. In this paper, a comprehensive literature for sensemaking is provided to formally define the notion of sensemaking in the military domain. Also, it is proposed that there is a crucial link between the sensemaking and human judgment process and performance from the lens model perspective. Potential implications for experimental framework are also proposed.