• Korean Journal of Radiology
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• v.22 no.5
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• pp.770-781
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• 2021

Objective: Chemical exchange-dependent saturation transfer (CEST) MRI is sensitive for detecting solid-like proteins and may detect changes in the levels of mobile proteins and peptides in tissues. The objective of this study was to evaluate the characteristics of chemical exchange proton pools using the CEST MRI technique in patients with dementia. Materials and Methods: Our institutional review board approved this cross-sectional prospective study and informed consent was obtained from all participants. This study included 41 subjects (19 with dementia and 22 without dementia). Complete CEST data of the brain were obtained using a three-dimensional gradient and spin-echo sequence to map CEST indices, such as amide, amine, hydroxyl, and magnetization transfer ratio asymmetry (MTR_asym) values, using six-pool Lorentzian fitting. Statistical analyses of CEST indices were performed to evaluate group comparisons, their correlations with gray matter volume (GMV) and Mini-Mental State Examination (MMSE) scores, and receiver operating characteristic (ROC) curves. Results: Amine signals (0.029 for non-dementia, 0.046 for dementia, p = 0.011 at hippocampus) and MTR_asym values at 3 ppm (0.748 for non-dementia, 1.138 for dementia, p = 0.022 at hippocampus), and 3.5 ppm (0.463 for non-dementia, 0.875 for dementia, p = 0.029 at hippocampus) were significantly higher in the dementia group than in the non-dementia group. Most CEST indices were not significantly correlated with GMV; however, except amide, most indices were significantly correlated with the MMSE scores. The classification power of most CEST indices was lower than that of GMV but adding one of the CEST indices in GMV improved the classification between the subject groups. The largest improvement was seen in the MTR_asym values at 2 ppm in the anterior cingulate (area under the ROC curve = 0.981), with a sensitivity of 100 and a specificity of 90.91. Conclusion: CEST MRI potentially allows noninvasive image alterations in the Alzheimer's disease brain without injecting isotopes for monitoring different disease states and may provide a new imaging biomarker in the future.

• Smart Media Journal
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• v.1 no.1
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• pp.53-57
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• 2012

Smart phone and its applications are currently bringing about significant changes in our lives and it is expected that applying such technology in the area of agriculture could increase the value added and productivity of agriculture with its various uses. This paper proposed a smartphone-based application for monitoring and managing livestock barn in real-time anytime, anywhere. In the proposed application, the livestock barn environment and video information collected in ubiquitous livestock barn based on wireless sensor networks can be used by user to monitor the livestock barn in real-time through the use of smart phone to control the livestock barn facilities anytime, anywhere. This application can provide user convenience and increase productivity by allowing users to control their livestock barn facilities.

• Journal of Information Technology Services
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• v.12 no.4
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• pp.461-472
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• 2013

Today, In the Service Industry are more getting a lot of convergence of IT utilization. And global IT companies are strengthening that platform based Services Ecosystems. These business in the field, Ecosystem Competitive strategy is difficult to imitate. And this strategy is generated organic Business Model that a by Competitive-Predominance to brings. In addition, the added value of the Service Industry is taken, a new type of job creation by the ripple-effect is huge. However, existing the Ecosystem Theory of Business is a lack of research on the use. Thus, Ecosystem Construction conditions is very difficult. This study is try to successful Platform Case's Analysis such as Apple, Google, Amazon, eBay's. These Ecosystems is that want to know the Major attributes. At first, would be analyzing to previous research, the Service and Knowledge Services' major attributes and Ecosystem studies' major attributes to grasp. Then, from a Group of Experts is to assess the importance. Finally, according to each Platform, examined the Correlation of Major Attributes.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.45-50
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• 2006

As a settlement for the fiber access, the FTTH is an ideal mode for providing various high-bandwidth value added services including high definition IPTV to broadband users, and KT, the largest incumbent of Korea, started FTTH service from 2005. For FTTH deployment, it needs a cost-effective solution including reliability and maintenance costs. This paper analyzes the characteristics and technical issues for the main components of outside plant in general household area.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.979-982
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• 2005

This paper is to be pre-processing that decides the text recognizability and quality contained in natural image. Differentiated with the existing studies, In this paper, it suggests the application of partially unified color models, Coiflet Wavelet and text extraction algorithm that uses the closed curve edge features of LoG (laplacian of gaussian)operator. The text image included in natural image such as signboard has the same hue, saturation and value, and there is a certain thickness as for their feature. Each color element is restructured into closed area by LoG operator, the 2nd differential operator. The text area is contracted by Hough Transform, logical AND-OR operator of each color model and Minimum-Distance classifier. This paper targets natural image into which text area is added regardless of the size and resolution of the image, and it is confirmed to have more excellent performance than other algorithms with many restrictions.

• Archives of design research
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• v.17 no.2
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• pp.363-372
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• 2004

In the new millenium of information and digital age, the vogue cycle has been gelling shorter and shorter and the individualistic and high quality preference of contemporary consumers drive the small quantity production by order. The traditional screen printing system can not hold the competitive edge anymore. In order to actively meet the demand of the fast evolving market, compete with other nations, and produce high value-added products, we need the new production system to meet the individual needs promptly. Mass production using the traditional screen printing system has the economic advantage of the production speed and cost. The digital textile printing system digitalizes the total process from the design to the printing and omits the separation and engraving. It is more suitable to produce the multiple item-small quantity and add more values to its products. It has also the advantage of less pollution problem.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.287-293
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• 2005

Ubiquitous Computing has introduced one of the most innovative international research contributions on the design and evaluation of new generations of handheld and mobile information appliances. New devices are being invented and existing devices are being improved with smaller size and increased mobility. These changes of computing paradigm are enabling the enterprises' legacy services to be automated and value-added all the more. We suggest a service framework and algorithms of provisioning healthcare services in a ubiquitous computing environment. We construct domain ontology that is related to diabetes and minimum common sense ontology for service composition. The results of this research enable integration and interconnection of devices, applications, and functions of enterprises within the healthcare services.

• Journal of Korea Multimedia Society
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• v.15 no.3
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• pp.312-322
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• 2012

The paper presents an approach for recognizing the broken area of the traffic signs. The method is based on the Recognition System for Traffic Signs (RSTS). This paper describes an approach to using the location histogram matching for the broken traffic signs recognition, after the general process of the image detection and image categorization. The recognition proceeds by using the SIFT matching to adjust the acquired image to a standard position, then the histogram bin will be compared preprocessed image with reference image, and finally output the location and percents value of the broken area. And between the processing, some preprocessing like the blurring is added in the paper to improve the performance. And after the reorganization, the program can operate with the GPS for traffic signs maintenance. Experimental results verified that our scheme have a relatively high recognition rate and a good performance in general situation.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.789-791
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• 2005

국내의 원격검침 데이터는 주로 전력요금 산출용도에 활용되고 있다. 하지만 국외 전력회사들은 미래 디지털 사회의 기반이 되는 신 전력시스템을 구현하는데 필요한 핵심기술 중의 하나로서 IT(Information Technology)기반 전력부가서비스 기술의 중요성에 대해 강조하고 있으며, 이를 위해 원격검침 데이터를 기반으로 하는 다양한 전력부가서비스를 개발하여 적용하고 있다. 따라서, 국내의 경우도 원격검침 데이터를 단순한 전력요금 산출용도가 아닌 전력소비자와의 관계에서 부가가치를 높일 수 있는 무한한 잠재력을 지닌 전략적인 자산으로 보고, 원격검침 데이터 가공 및 활용기술의 선진화를 통하여 전력회사와 전력소비자 모두에게 필요한 전력부가서비스의 적용이 필요하다. 본 논문에서는 국내외 전력부가서비스 시스템의 비교 분석을 통해 국내 전력산업 환경에 적합한 새로운 전력 부가서비스 적용방향을 제시하고, 이를 기초로 설계한 전력부가서비스의 일종인 전력 에너지 컨설팅 서비스 시스템에 대해 소개하고자 한다. 설계한 전력부가서비스 시스템의 적용시 전력소비자 측면에서는 요금절감 효과가 전력회사 측면에서는 부하 수요관리 및 투자비 절감 효과가 예상된다.

• Communications for Statistical Applications and Methods
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• v.25 no.2
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• pp.217-234
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• 2018

Copulas are a tool for constructing multivariate distributions and formalizing the dependence structure between random variables. From copula literature review, there are a few asymmetric copulas available so far while data collected from the real world often exhibit asymmetric nature. This necessitates developing asymmetric copulas. In this study, we discuss a method to construct a new class of bivariate asymmetric copulas based on products of symmetric (sometimes asymmetric) copulas with powered arguments in order to determine if the proposed construction can offer an added value for modeling asymmetric bivariate data. With these newly constructed copulas, we investigate dependence properties and measure of association between random variables. In addition, the test of symmetry of data and the estimation of hyper-parameters by the maximum likelihood method are discussed. With two real example such as car rental data and economic indicators data, we perform the goodness-of-fit test of our proposed asymmetric copulas. For these data, some of the proposed models turned out to be successful whereas the existing copulas were mostly unsuccessful. The method of presented here can be useful in fields such as finance, climate and social science.