• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.972-978
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• 2009

In order to achieve color constancy, this paper proposes a method that can detect an invariant direction that affects formation of an intrinsic image significantly, using eigenvector in the $\chi$-chromaticity space. Firstly, image is converted into datum in the $\chi$-chromaticity space which was suggested by Finlayson et al. Secondly, it removes datum, like noises, with low probabilities that may affect an invariant direction. Thirdly, so as to detect the invariant direction that is consistent with a principal direction, the eigenvector corresponding to the largest eigenvalue is calculated from datum extracted above. Finally, an intrinsic image is acquired by recovering datum with the detected invariant direction. Test images were used as parts of the image data presented by Barnard et al., and detection performance of invariant direction was compared with that of entropy minimization method. The results of experiment showed that our method detected constant invariant direction since the proposed method had lower standard deviation than the entropy method, and was over three times faster than the compared method in the aspect of detection speed.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.10
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• pp.21-29
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• 2015

For higher reliability against component failures in railroad trains with many electronic sensors and actuators, a distributed control system with which all electronic components are connected via a network is being considered. This paper compares and analyzes various topologies of Ethernet network for a railroad train in the aspects of (1) failure recovery, (2) the number of ports per device, (3) the number of cable connections between vehicles, and (4) performance. Especially, the unique characteristic of a train system that the number of vehicles changes is considered through analysis. Various combinations of in- and inter-vehicle topologies are considered. In addition, we introduce a hybrid of star and daisy-chain topology for inter-vehicle connection when the maximum number of inter-vehicle connections is limited to reduce possible failures of inter-vehicle connections. Simulation results show performance comparison between different topology combinations; the hybrid topology is shown to enhance delay performance even with a highly limited number of inter-vehicle connections.

• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.74-81
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• 2015

As one of urban infrastructure system, the electricity substation is critical for urban life and industrial activity as the electricity demands get higher than ever. However the substation is generally regarded as unpleasant or dangerous facility, which finally results in the continuous opposition movement by resident due to the belief of unidentified negative effect in apartment prices. Accordingly, as the scientifically objective and quantitative analysis is required to solve the social conflict, this study intends to examine the variation affected by urban infrastructure system, expecially for substation. After the independent variable defining the price of apartment and the dependent variable, which is apartment price, are identified and their spatial data has been filed, the forecasting model has been developed through the hedonic price function as well as artificial neural networks system. The research finding indicated that the spatial range affected by substation is not notable and the range of some case was applicable for less than 600m. It is expected that these research findings can be applied for establishing the one of solid cases for the analysis of economical effect to local housing market by the urban infrastructure system.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.1
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• pp.31-44
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• 2020

Accelerators that invest in early startups, as well as nursery and overall management, have recently emerged as "key players" in the startup ecosystem. This can be proved by the case where the number of domestic accelerators registered in the Korean Ministry of SMEs and Startups has recently reached 208. Accelerators provide the necessary education for early-stage companies, including guidance for a certain period of time, and support startups in ways such as demo days to attract subsequent investment after the seed investment. There is not much research in academia about what factors impact on these accelerators when making investment decisions at the time of seed investment. In this study, we checked the meaning and function of the accelerator and tried to analyze what factors affect on accelerators when making a decision to invest in startups. The research method is based on a literature survey of previous studies on investment decision-making factors of venture capital and angel investors, and a lens model and judgment analysis method through empirical research targeting 43 accelerator investment decision-makers. Empirical analysis shows that accelerators have three of the key factors to consider when choosing the first startup to invest and educate; entrepreneurs' entrepreneurial traits, their product and service expertise and a potential return on success. This will provide an opportunity for early startups to gain strategic access to accelerators when they need money or need a structured educational program. Also, the results obtained through this research will be a kind of guideline for startups to attract accelerators' investment. The significance of this study is that discriminatory evidence was presented on the accelerator determinants of investment, and it would be highly suggestive to startups and related public institutions.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.2 s.40
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• pp.87-93
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• 2007

Over the years, Advanced Public Transportation System (APTS) has been implemented to manage and operate public transportation system. With the expanding mass spatio-temporal data such as comprehensive spatial information of each individual passenger and public transportation vehicle, it has been required to consolidate and analyze these multiple data sets from various sources. This paper demonstrates how GIS is utilized for the consolidation of massive transit related spatio-temporal information. And it presents effective applications to improve transit planning process and support transit related decision-making activities. GIS based system is used to combine multi-agents' data in the areas of transit operation and individual transit ride and transfer management. Due to the unique comprehensiveness and the level of detail of the data provide by the Seoul Transit system, this GIS based information consolidation is the first in its class. Based on the integrated database, this paper describes the effective and efficient GIS based analysis deployed in a transportation system planning process. The data integration systems and analytic models developed in this paper can be transferred and applied by any municipal governments provided that the appropriate data is available.

• Journal of Korea Multimedia Society
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• v.7 no.1
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• pp.132-144
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• 2004

With the rapid development of internet technology, the number of internet users and the amount of multimedia information on the internet is ever increasing. Recently, the web sites, such as e-business sites and shopping mall sites, deal with lots of image information. As a result, it is required to support content- based image retrieval efficiently on such image data. This paper proposes an intelligent image retrieval system, which adopts XML, technology. To support object-based col)tent retrieval on product catalog images containing multiple objects, we describe a multi -level metadata structure which represents the local features, global features, and semantics of image data. To enable semantic-based and content-based retrieval on such image data, we design a XML-Schema for the proposed metadata and show how to represent such metadata using XML- documents. We also describe how to automatically transform the retrieval results into the forms suitable for the various user environments, such as web browser or mobile browser, using XSLT The proposed scheme can be easily implemented on any commercial platforms supporting XML technology. It can be utilized to enable efficient image metadata sharing between systems, and it will contribute in improving the retrieval correctness and the user's satisfaction on content-based e-catalog image retrieval.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.755-761
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• 2017

This study was conducted to establish an analytical method using an HPLC system equipped with a photodiode array (PDA) detector for the quality control of raw materials and cosmeceuticals containing fucoxanthin as an active ingredient. The column was octadecyl-functionalized silica gel and the measurement wavelength of the PDA was set to 499 nm. To validate the analytical method, the linearity of the calibration curve, detection limit, reproducibility and recovery rate were investigated and good results were obtained. The correlation coefficient of the calibration curve was 1.000 and the linearity was good in the concentration range of 0.5 ~ 100 ppm. Moreover, the limit of detection (LOD) was 0.1 ppm and the limit of quantification (LOQ) was 0.5 ppm. The results of the peak reproducibility test used for evaluating the system suitability showed that the RSD (n = 5) of the peak area was 2.0% and that of the retention time was 0.09%. In the spiking test, the recovery rate was $101.6{\pm}0.77%$. The fucoxanthin contents of the two kinds of fucoxanthin-containing raw materials were $49.6{\pm}3.3%$ and $1.03{\pm}0.016%$, respectively. In addition, the fucoxanthin content in the test product, which was intended to be 150 ppm, was $156.7{\pm}4.7ppm$. From the above results, it was concluded that this method could be applied to the quantitative analysis of fucoxanthin in cosmeceuticals.

• Journal of the Korean Institute of Intelligent Systems
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• v.7 no.3
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• pp.43-54
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• 1997

Knowledge acquisition is one of the most difficult problems in designing fuzzy systems. As application domains of fuzzy systems become larger and more complex, it is more difficult to find the relations among the system's input- outpiit variables. Moreover, it takes a lot of efforts to formulate expert's knowledge about complex systems' control actions by linguistic variables. Another difficulty is to define and adjust membership functions properly. Soin conventional fuzzy systems, the membership functions should be adjusted to improve the system performance. This is time-consuming process. In this paper, we suggest a new approach to design a fuzzy system. We design a fuzzy system using two neural networks, Kohonen neural network and backpropagation neural network, which generate fuzzy rules automatically and construct inference network. Since fuzzy inference is performed based on fuzzy relation in this approach, we don't need the membership functions of each variable. Therefore it is unnecessary to define and adjust membership functions and we can get fuzzy rules automatically. The design process of fuzzy system becomes simple. The proposed approach is applied to a simulated automatic car speed control system. We can be sure that this approach not only makes the design process of fuzzy systems simple but also produces appropriate inference results.

• Journal of KIISE:Computing Practices and Letters
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• v.9 no.6
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• pp.646-661
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• 2003

It is not easy that we visualize the large volume data stored in the every client computers of the web environment. One solution is as follows. First we compress volume data, second store that in the database server, third transfer that to client computer, fourth visualize that with direct-volume-rendering in the client computer. In this case, we usually use wavelet transform for compressing large data. This paper reports the experiments for acquiring the wavelet bases and the compression ratios fit for the above processing paradigm. In this experiments, we compress the volume data Engine, CThead, Bentum into 50%, 10%, 5%, 1%, 0.1%, 0.03% of the total data respectively using Harr, Daubechies4, Daubechies12 and Daubechies20 wavelets, then visualize that with direct-volume-rendering, afterwards evaluate the images with eyes and image comparison metrics. When compression ratio being low the performance of Harr wavelet is better than the performance of the other wavelets, when compression ratio being high the performance of Daubechies4 and Daubechies12 is better than the performance of the other wavelets. When measuring with eyes the good compression ratio is about 1% of all the data, when measuring with image comparison metrics, the good compression ratio is about 5-10% of all the data.

• Journal of The Korean Association For Science Education
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• v.33 no.7
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• pp.1285-1299
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• 2013

Nurturing students' scientific creativity is considered an important element in science education in Korea. The study aims to explore patterns displayed by well-known scientists in their quest for problem finding. Each case of scientists' course of problem solving is described in terms of historical background, a process of problem finding, and a process of problem solving. There are five patterns from ten scientists which are as follows: Pattern 1 is that scientists find problems from insufficiencies and/or errors from explanation of theories at the time and the related cases are A. Lavoisier, G. Mendel, and J. Watson. Pattern 2 shows that scientists find a problem because of strange phenomena unexplained by theories at the time, and here important case studies are E. Rutherford and W. R$\ddot{o}$ntgen. Pattern 3 demonstrates that scientists find a problem from analogical reasoning between known theories and unknown science phenomena. The cases include S. Carnot and T. Young. Pattern 4 points to the fact that scientists find a problem while they utilize a newly invented experimental instrument. Here, G. Galilei is an important example. Pattern 5 establishes that scientists happen to find a problem while they conduct research projects. The works of M. Faraday and J. Kepler are prominent case studies related to this pattern.