• Archives of Pharmacal Research
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• v.21 no.4
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• pp.478-480
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• 1998

The structure activity relationship of flavonoids for anti-allergic actions was studied by determining the $IC_{50}$ values for the degranulation. The hexosaminidase release from RBL-2H3 cells (degranulation marker) was employed as an estimate for the anti-allergic actions. Among 22 flavonoid compounds tested, luteolin, apigenin, diosmetin, fisetin, and quercetin were found to be most active with $IC_{50}$ values less than 10 $\mu\textrm{M}$.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.2
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• pp.55-61
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• 2002

In this paper, 'lifetime-temperature rise model' based on the 'lifetime-resistance model' is theoretically Proposed, in order to find out the evaluation method of degradation and the residual lifetime by use of infrared image camera for electric connections/contacts. Two assumptions have been builded up for the 'lifetime-temperature rise model': one is associated with the linear relationship between the temperature ism ΔK and contact resistance, and the other the functional relationship between the temperature of electric connections/contacts and the operating time presenting in the 'lifetime-resistance model'. To prove the proposed model, experiments have been performed for various electric connections/contacts. From the experimental results, measured values were quite similar to the calculated values, which proved the above-mentioned two assumptions. Therefore, by use of 'lifetime-temperature rise model', it is possible to estimate the trend of degradation and the residual lifetime for electric connections/contacts through the temperature measurements .

• Journal of Korea Multimedia Society
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• v.19 no.8
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• pp.1386-1394
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• 2016

Pyramid fusion usually adjusts the Laplacian weights of pixels of the input images by evaluating predefined criteria. This has advantages that it can selectively express intense color and enhance the contrast when applied to HDR exposure fusion. But it may cause noise because the weights are determined by pixel importance without considering the interdependent pixel relationship that constitutes a scene. This paper proposes a fusion method using simple weight criteria generated from the gray pixel values, which is expected to preserve the interdependent relationship and improve execution speed. In order to evaluate the performance of the proposed method we examine a homogeneity measure, H and compare the execution time for both methods. The proposed method is found to be more advantageous with respect to homogeneity and execution speed.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.2
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• pp.397-405
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• 1999

Purpose: To clarify the usefulness and the limitation of Digora system/sup (R)/ by evaluating the physical characteristics as the quantitative image on Image Plate(Ip). Materials and Methods: Radiograms were taken by Heliodent MD(Siemens Co.. Germany) with the image plate for adult. Cu-step wedge as reference material. and three pieces of dry mandibular bone. Image analysis was performed by single color enhancement. density measurement with histogram. The relationship between the exposure conditions and the distribution of the pixel values of the image. the variation of pixel values of each step of Cu-step wedge at two different area and Cu-equivalent value of three pieces of dry mandibular bone measure by the conversion equation. Results: There was no linear relationship between the exposure condition and the average pixel value of the image. of which the distribution was not even. The pixel value differences between the center portion and the periphery were ranged from 60 to 70 in vertical plane and from 15 to 26 in horizontal plane. Two plot profile formed at two different areas of the Cu-step wedge were different. The measured Cu-equivalent values showed the discrepancy among the times of measurement. Conclusion: As above results. Image Plate(Ip) of Digora system/sup (R)/ showed the limitation as the quantitative image. The physical property of IP was expected to need to be compensated for the quantitative evaluation of the bone or others

• Journal of Digital Convergence
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• v.10 no.6
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• pp.171-179
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• 2012

In this study, production of the psychological characteristics of college, and work values, and adjusting to college by examining the relationship between the impact and importance of college life was to become the basis of map. The results of this study First, the psychological characteristics of college production to adjust to college has a positive effect. In particular, self-esteem, how the formation of ego identity doeneunyae adjustment to college so well that the results could be obtained. Second, the psychological characteristics of college production value of the job was not found to affect the formation. Finally, the work value adjustment to college life was not affected by.

• Journal of the Korean Institute of Intelligent Systems
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• v.5 no.2
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• pp.3-12
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• 1995

A controller utilizing fuzzy logic is developed to control the speed of a motor in a washing machine by choosing an appropriate phase. Due to the hardship imposed on obtaining a result from a relation established for inputs, present speed and present rate of speed, and ouput, a phase, of the system that can be tested against an experimental result, it is impossible to apply a genetic algorithm to fine-tune the fuzzy logic controller. To avoid this difficulty, a proper assumption that the parameters of an if-part of a primary fuzzy logic controller have a functional relationship with an error between computed values and experimental ones in made. Setting up of a fuzzy relationship between the parameters and the errors is then achieved through experimentally obtained data. Genetic Algorithm is then applied to this secondary fuzzy logic controller to verify the fuzzy logic. In the verification process, the primary fuzzy logic controller is used in obtaining experimental results. In this way the kind of difficulty in obtaining enough experimental values used to verify the fuzzy logic with genetic algorithm is gotten around. Selection of the parameters that would produce the least error when using the secondary fuzzy logic controller is done with applying genetic algorithm to the then-part of the controller. In doing so the optimal values for the parameters of the if-part of the primary fuzzy logic controller are assumed to be contained. The experimental result presented in the paper validates the assumption.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.687-695
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• 2009

The present study attempted to offer more insights into the foreign consumers' consumption decision structure of Korean restaurants located in foreign countries. A survey was designed based on the means-end chain theory, using the laddering interview technique. The qualitative data obtained from 10 Americans, 10 Japanese, and 10 Chinese were content analyzed and resulted in categories such as 'new experience', 'interest in Korea', 'recommendation', 'good food', 'easy to access', 'service', 'dining environment', and 'price' as perceived attributes of choice. The hierarchical value maps linking attributes, psychological consequences, and terminal values were presented. The most frequent consequences were 'experience new culture', 'be exposed to new experience', and 'learn more about Korea' which were related to 'happiness', 'pleasure', 'good relationship', 'desire fulfillment', and 'self-satisfaction' as personal values. Laddering interviews, which required laborious analysis, provided important information on the relationship between perceived attributes and the reasons for choosing Korean restaurants.

• The Korean Journal of Physiology and Pharmacology
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• v.13 no.6
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• pp.511-516
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• 2009

A series of substituted 2-arylnaphthyridin-4-one analogues, which were previously synthesized in our laboratory, were evaluated for their in vitro cytotoxic activity against human lung cancer A549 and human renal cancer Caki-2 cells using MTT assay. Some compounds (11, 12, and 13) showed stronger cytotoxicity than colchicine against both tumor cell lines, and compound 13 exhibited the most potent activity with $IC_{50}$ values of 2.3 and $13.4\;{\mu}M$, respectively. Three-dimensional quantitative structure activity relationship (3D-QSAR) studies of comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were performed. Predictive 3D-QSAR models were obtained with $q^2$ values of 0.869 and 0.872 and $r^2_{ncv}$ values of 0.983 and 0.993 for CoMFA and CoMSIA, respectively. These results demonstrate that CoMFA and CoMSIA models could be reliably used in the design of novel cytotoxic agents.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.457-461
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• 2007

In many applications, received signal strength indicator is used for location tracking and sensor nodes localization. For location finding, the distances between sensor nodes can be estimated by converting received signal's power into distance using path loss prediction model. Many researches have done the analysis of power-distance relationship for radio channel characterization. In indoor environment, the general conclusion is the non-linear variation of RSSI values as distance varied linearly. This has been one of the difficulties for indoor localization. This paper presents works on indoor RSSI characterization based on statistical methods to find the overall trend of RSSI variation at different places and times within the same room From experiments, it has been shown that the variation of RSSI values can be determined by both spatial and temporal factors. This two factors are directly indicated by the two main parameters of path loss prediction model. The results show that all sensor nodes which are located at different places share the same characterization value for the temporal parameter whereas different values for the spatial parameters. Using this relationship, the characterization for location estimation can be more efficient and accurate.

• The Journal of Korean Academic Society of Nursing Education
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• v.20 no.4
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• pp.587-595
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• 2014

Purpose: This study undertakes to identify factors influencing the perception university students in Korea hold toward having children. Method: A cross-sectional, descriptive study was conducted on 187 university students (79 males and 108 females) from one university located in a metropolitan area. Participating students completed a packet of self-report questionnaires on values concerning gender roles, marriage, family and children along with their personal demographic details. The resulting data were analyzed using t-tests, one-way ANOVA and Pearson's correlation coefficients as well as descriptive statistics. Stepwise multiple regression was performed to identify factors that most influenced the value of children held among university students. Results: The value of having children was negatively associated with the value of family, but positively associated with the value of marriage. In addition, the value of family had a negative relationship with the value of marriage, but a positive relationship with the value of gender role. Stepwise multiple regression found that the equation consisting of gender and value of marriage explained about 42.0% of the variance of the value of having children. Conclusion: Considering the findings from this study, programs promoting the positive values of marriage are required for university students to have positive values toward having children.