• ETRI Journal
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• v.46 no.3
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• pp.513-525
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• 2024

Deep neural networks trained on labeled medical data face major challenges owing to the economic costs of data acquisition through expensive medical imaging devices, expert labor for data annotation, and large datasets to achieve optimal model performance. The heterogeneity of diseases, such as Alzheimer's disease, further complicates deep learning because the test cases may substantially differ from the training data, possibly increasing the rate of false positives. We propose a reconstruction-based self-supervised anomaly detection model to overcome these challenges. It has a dual-subnetwork encoder that enhances feature encoding augmented by skip connections to the decoder for improving the gradient flow. The novel encoder captures local and global features to improve image reconstruction. In addition, we introduce an entropy-based image conversion method. Extensive evaluations show that the proposed model outperforms benchmark models in anomaly detection and classification using an encoder. The supervised and unsupervised models show improved performances when trained with data preprocessed using the proposed image conversion method.

• Journal of applied mathematics & informatics
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• v.42 no.2
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• pp.305-320
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• 2024

We consider a mathematical model which describes the quasistatic contact of electro-viscoelastic rod with an obstacle. We use a modified Kelvin-Voigt viscoelastic constitutive law in which the elasticity operator is nonlinear and locally Lipschitz continuous, taking into account the piezoelectric effect of the material. We model the contact with a general damped response condition. We establish a local existence and uniqueness result of the solution by using arguments of time-dependent nonlinear equations and Schauder's fixed-point theorem and obtain a global existence for small enough data.

• Cartoon and Animation Studies
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• s.40
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• pp.243-260
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• 2015

Being a symbolic image to let traditional 'mother wonlee' contents characters known widely, need to be made in a way that can deliver the powerful message of korea An-dong traditional local contents and the value of regent story. As for the contents character develope methods and the scope of the study, an theoretical study was conducted based on literature review, and, factor plus fiction field surveys, and the legend story and then an effect of character marketing on global contents with original identity. 'mother wonlee' pre-production plaining have been analysis with creative described based on the ancients features and the classification of ancient original characters, and the situation and the concept of An-dong local place. as a results this thesis is show up how to make up a main character develop processing and make a features design processing of the characters who different age and a scenes. as a conclusion is drawing about a 'Wonlee' and 'Eungtea' both main Character plaining processing and graphics; traditional face, all clothes, body proportion, etc. Also we trade to traditional patten with character planing. it will be a high value industry which facilitates a variety of industries in conjunction with marketing traditional source characters in global. Recognizing the value of traditional story main character design and graphics marketing and utilizing the value through various media will create infinite value, enabling the global marketing.

• The Korean Journal of Applied Statistics
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• v.33 no.3
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• pp.335-345
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• 2020

This paper deals with the problem of estimating the log-transformed linear regression model to fit actual battle data from the Ardennes Campaign of World War II into the Lanchester model. The problem of determining a global solution for parameters and multicollinearity problems are identified and modified by examining the results of previous studies on data. The least squares method requires attention because a local solution can be found rather than a global solution if considering a specific constraint or a limited candidate group. The method of exploring this multicollinearity problem can be confirmed by a statistic known as a variance inflation factor. Therefore, the Lanchester model is simplified to avoid these problems, and the combat power attrition rate model was proposed which is statistically significant and easy to explain. When fitting the model, the dependence problem between the data has occurred due to autocorrelation. Matters that might be underestimated or overestimated were resolved by the Cochrane-Orcutt method as well as guaranteeing independence and normality.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1361-1374
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• 2010

The impact of urbanization on local meteorology (e.g., surface temperature, PBL height, wind speed, etc.) in the Greater Seoul Area (GSA) was quantitatively evaluated based on a numerical modeling approach during a 1-month period of 2001 (9 Sep. through 8 Oct. 2001). The analysis was carried out by two sets of simulation scenarios: (1) with the global land use and topographic data from the U.S. Geological Survey (USGS) in 1990s (i.e., LU-USGS case) and (2) with the land use data from the Environmental Geographic Information System (EGIS) along with the 3 sec elevation data from the Shuttle Radar Topography Mission (SRTM) in 2000s (i.e., LU-EGIS case). The extension of urban areas in the GSA (especially, the southern parts of Seoul) accounted for 1.8% in the LU-USGS case and 6.2% in the LU-EGIS case. For the simulations, the surface temperature and PBL height due to urbanization in the LU-EGIS case was higher (the differences of up to $0.1^{\circ}C$ and 36 m, respectively) than those in the LU-USGS case, whereas the wind speed (up to 0.3 $ms^{-1}$) in the former was lower than that in the latter at 1500 LST. The increase in surface temperature due to urbanization in the GSA (especially, the southern parts of Seoul) was led to the strong convergence of air masses, causing the early sea breeze and its rapid propagation to inland locations. In addition, the vertical mixing motion in the extended urban areas for the LU-EGIS case was predicted to be stronger than that for the LU-USGS case and vice versa for the original urban areas.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.1
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• pp.25-44
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• 2010

With the increasing popularity of mobile devices, it has become necessary to protect private information and content in these devices. Face recognition has been favored over conventional passwords or security keys, because it can be easily implemented using a built-in camera, while providing user convenience. However, because mobile devices can be used both indoors and outdoors, there can be many illumination changes, which can reduce the accuracy of face recognition. Therefore, we propose a new face recognition method on a mobile device robust to illumination variations. This research makes the following four original contributions. First, we compared the performance of face recognition with illumination variations on mobile devices for several illumination normalization procedures suitable for mobile devices with low processing power. These include the Retinex filter, histogram equalization and histogram stretching. Second, we compared the performance for global and local methods of face recognition such as PCA (Principal Component Analysis), LNMF (Local Non-negative Matrix Factorization) and LBP (Local Binary Pattern) using an integer-based kernel suitable for mobile devices having low processing power. Third, the characteristics of each method according to the illumination va iations are analyzed. Fourth, we use two matching scores for several methods of illumination normalization, Retinex and histogram stretching, which show the best and $2^{nd}$ best performances, respectively. These are used as the inputs of an SVM (Support Vector Machine) classifier, which can increase the accuracy of face recognition. Experimental results with two databases (data collected by a mobile device and the AR database) showed that the accuracy of face recognition achieved by the proposed method was superior to that of other methods.

• Korean Journal of Clinical Pharmacy
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• v.29 no.4
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• pp.267-277
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• 2019

Backgrounds: With the globalization of drug development, multi-regional clinical trials (MRCTs) have emerged to facilitate rapid availability of medicines to patients worldwide. The present study aimed to has explored attitudes and perceptions towards adopting the Korean MRCT guideline. Methods: An online survey, consisting of 16 questions, classified into two subjects, was administered to stakeholders in Korea. Most quantitative components were measured using the Likert scales. A content analysis of the qualitative components was carried out to identify the keywords in open-ended responses. Results: A total of 94 survey responses were analyzed: 51 participants from pharmaceutical companies, 11 from clinical research organizations, and 21 from clinical trial centers. The content of the guideline was rated as appropriate for clarity, acceptability, and applicability (96.8, 96.8, and 93.6%, respectively). The local environmental impact of the systemic/political, academic/technical, and industrial/economical aspects of the guideline was rated as appropriate at 95.7, 97.9, and 91.5%, respectively. The suggested adoption period was 1~2 years (40, 42.6%). The concept and individuals' domestic circumstances were the key problems affecting the clarity, applicability, and local environmental impact of the guideline. Conclusion: The Korean MRCT guideline was well-developed. Their overall impact on the local environmental impact of MRCTs in Korea was expected to be beneficial, but methods are needed to minimize the negative impacts. The findings of this study can inform the priorities for the future adoption of the guideline in Korea.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.40.3-40.3
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• 2019

There is growing evidence for the dependence of Type Ia supernova (SN Ia) luminosities on the environments. The origin of this correlation, however, is under debate. In order to explore the physical origin of the trend in detail, we analyze SN Ia light-curves by combining a sample of 1231 SNe Ia over a wide redshift range (0.01 < z < 1.37) in various SN surveys and employing two independent light-curve fitters of SALT2 and MLCS2k2. Although SALT2 is the most widely used fitter in the SN community, MLCS2k2 has a novelty in the context of an investigation of the luminosity evolution of SNe Ia. For this reason we use both fitters and analyze them separately. We also determine a stellar mass and a star formation rate (SFR) for a sample of ~600 host galaxies. In addition, because recent low-redshift studies suggest that this dependence manifests itself most strongly when using the local SFR at the SN location, we introduce a new method to infer the local environments by restricting the SN Ia sample in globally star-forming host galaxies to a low-mass host galaxy subset (${\leq}10^{10}M_{\odot}$). We find that SNe Ia in low-mass and star-forming host galaxies are fainter than those in high-mass and passive hosts, after light-curve corrections. Especially, for the first time in host studies, we show that SNe Ia in locally star-forming environments are $0.081{\pm}0.018$ mag fainter ($4.5{\sigma}$) than those in locally passive environments from the sample including SNe at the high-redshift range. Considering the significant difference in the mean stellar population age between these environments, the result would suggest that the origin of the environmental dependence is the luminosity evolution of SNe Ia.

• Journal of Korea Trade
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• v.24 no.8
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• pp.189-206
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• 2020

Purpose - This paper attempted to verify the process by which a multinational corporation (MNC)'s subsidiary practices entrepreneurship to create effective knowledge (KC) in the local market. We have looked at whether subsidiary entrepreneurship (SENT) has a moderation effect in creating knowledge for the local market when a subsidiary has been given autonomy (AUT) from the headquarters (HQ). We also argue that when a subsidiary creates meaningful knowledge, the effect of the increased status by the HQ within the MNC network position (NP) has an indirect effect on whether knowledge is transferred to other overseas subsidiaries (KTO). Design/methodology - This paper used a structural equation model (SEM) of 282 effective foreign companies invested in Korea. To test the hypothesis about the process of SENT on KTO, descriptive statistics, confirmatory factor analysis, reliability, convergent and discriminant validities, and common method bias were analyzed using STATA. In addition, the moderation effect was verified along with SEM. The moderation effect of AUT on SENT and KC was presented graphically by confirming \mathrm{\pm1} standard deviation of AUT for the main effect. Findings - Our findings are as follows. First, while the hypothesis about the direct effect of SENT and KC on KTO was not supported, all other hypotheses were supported. Second, both the AUT and moderating effect and the indirect effect of NP were significant. In the conclusion, these findings are discussed in relation to its various theoretical and practical implications. Originality/value - This study attempted to contribute to the knowledge creation theory of MNC by contemplating how subsidiaries can move away from HQ and grow in the local market. Although there is still a shortage of foreign investment in the Korean market, our practical implications offer guidance for how current subsidiaries can develop more than other overseas subsidiaries.

• SUVANNABHUMI
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• v.10 no.1
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• pp.63-91
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• 2018

One of the goals of this article is to continue the momentum begun by emerging scholarship on theory and practice of writing about visual culture of and in Southeast Asia. I hope to offer culturally sensitive and embodied ways of looking at images and objects as sites/sights of cultural knowledge as further theoretical intervention. The argument put forward in my essay is three-fold: first, I critique the prevailing logocentric approach in the field of Southeast Asian Studies and I argue that in a postcolonial, global, and transnational period, it is important to be inclusive of other objects as sites/sights of social, political and cultural analysis beyond written and oral texts. Second, I argue that although it has its own political and theoretical problems, the evolving field of Visual Studies as it is practiced in the United States is one of many ways to decolonize the prevailing logocentric approach to Southeast Asian Studies. Third, I argue that if one reads these Euro-American derived theories of vision and visuality through the lens of what Walter Mignolo calls "colonial difference(s)," then Visual Studies as an evolving field has the potential to offer more nuanced local ways of looking at and understanding objects, vision, and visuality. Last, I point out that unlike in the West where there is an understanding of pure, objective and empirical vision, local Southeast Asian perspectives on objects and visions are more embodied and multi-sensorial. I argue that if one is ethically mindful of the local cultural ways of seeing and knowing objects, then the evolving field of Visual Studies offers a much-needed intervention to the privileged, lingering logocentric approach to Southeast Asian Studies. Moreover, these alternative methods might help to decolonize method and theory in academic disciplines that were invented during the colonial period.