• Journal of Korea Multimedia Society
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• v.4 no.5
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• pp.423-429
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• 2001

In this paper, we propose the improved method for retrieving images with DC element of DCT that is used in image compression such as JPEG/MPEG. The existing method retrieves images with DC of fixed block size DCT. In this method, the increase in the block size results in faster retrieving speed, but it lessens the accuracy. The decrease in the block size improves the accuracy, however, it degrades the retrieving speed. In order to solve this problem, the proposed method utilizes the variable block size DCT. This method first determines the existence of object regions within each block, and then creates an image region table. Based on this table, it determines the size of each block, following a simple rule; decrease the block size in the object regions, and increase the block size in the background regions. The proposed method using variable block size DCT improves about 15% in terms of the accuracy. Additionally, when there rarely exist images of same pattern, it is able to retrieve faster only by comparing the image region patterns.

• Transactions of the Society of Information Storage Systems
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• v.1 no.2
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• pp.155-160
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• 2005

In this paper, the channel decoder promising reliable data retrieving in noisy holographic channel has been developed for holographic WORM(write once read many) system. It covers various DSP(digital signal processing) blocks, such as align mark detector, adaptive channel equalizer, modulation decoder and ECC(error correction code) decoder. The specific schemes of DSP are designed to reduce the effect of noises in holographic WORM(H-WORM) system, particularly in prototype of DAEWOO electronics(DEPROTO). For real time data retrieving, the channel decoder is redesigned for FPGA(field programmable gate array) based hardware, where DSP blocks calculate in parallel sense with memory buffers between blocks and controllers for driving peripherals of FPGA. As an input source of the experiments, MPEG2 TS(transport stream) data was used and recorded to DEPROTO system. During retrieving, the CCD(charge coupled device), capturing device of DEPROTO, detects retrieved images and transmits signals of them to the FPGA of hardware channel decoder. Finally, the output data stream of the channel decoder was transferred to the MPEG decoding board for monitoring video signals. The experimental results showed the error corrected BER(bit error rate) of less than $10^{-9}$, from the raw BER of DEPROTO, about $10^{-3}$. With the developed hardware channel decoder, the real-time video demonstration was possible during the experiments. The operating clock of the FPGA was 60 MHz, of which speed was capable of decoding up to 120 mega channel bits per sec.

• Korean Journal of Optics and Photonics
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• v.29 no.4
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• pp.139-148
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• 2018

In this study, aerosol size distributions were retrieved from aerosol optical depth measured over a range of 10 wavelengths from 250 to 1100 nm. The 10 wavelengths were selected where there is no absorption of atmospheric gases. To obtain the solar spectrum, a home-made solar tracking system was developed and calibrated. Using this solar tracking system, total optical depths (TODs) were extracted for the 10 wavelengths using the Langley plot method, and aerosol optical depths (AODs) were obtained after removing the effects of gas absorption and Rayleigh scattering from the TODs. The algorithm for retrieving aerosol size distributions was suggested by assuming a bimodal aerosol size distribution. Aerosol size distributions were retrieved and compared under various arbitrary atmospheric conditions. Finally, we found that our solar tracking spectrometer is useful for retrieving the aerosol size distribution, even though we have little information about the aerosol's refractive index.

• Journal of The Korean Association For Science Education
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• v.34 no.5
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• pp.511-521
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• 2014

In this study, we conducted an exploratory investigation of the imaginative writing processes of middle school students. Twelve 8th graders were asked to imagine and write about the daily life of atoms, assuming that they became specific atoms for themselves. The think-aloud method was used to investigate students' writing processes. We recorded students' writing processes, and also collected the data through interviews to clarify ambiguities in their writing processes. The analyses of the results revealed that their imaginative writing processes could be classified into the three types by the two aspects of writing process components (retrieving information and generating ideas). That is, the integration of retrieving information and generating ideas, the predominant retrieving information, and the predominant generating ideas. The students who were classified into the type of the integration of retrieving information and generating ideas came up with a story and properly introduced science concepts into it. These suggested that this type of students expressed their own understanding more effectively, and that this type was most appropriate for imaginative writing in learning science. The results also showed that the imaginative writing processes were greatly influenced by whether the planning step was adequately considered or not. On the bases of the results, we suggest the teaching strategies for effective imaginative writing in learning science.

• Proceedings of the Korean Society for Information Management Conference
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• 1999.08a
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• pp.173-176
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• 1999

인터넷 환경에서는 정보자원을 식별하기 위한 기호로서 URL을 사용하고 있다. 그러나 URL은 자원이 위치한 장소를 지시하기 때문에 자원의 위치가 변경될 경우에는 접근하지 못한다는 단점이 있다. 본 논문에서는 이러한 URL의 단점을 보완하기 위한 대안으로서 URN을 이용하여 국내 학위논문을 고유하게 식별하고 검색하기 위한 방안에 대해 연구하였다.

• Proceedings of the IEEK Conference
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• 2000.06c
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• pp.71-74
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• 2000

New methods for storing and retrieving semi-structured data such XML documents has been recently studied. In this paper, we concern querying of XML data stored in relational tables. We first describe a method of querying XML documents using Oracle XDK, especially XSQL Servlet. We then apply the method to XML documents describing book information.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.357-358
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• 2011

• Bioinformatics and Biosystems
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• v.1 no.2
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• pp.95-98
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• 2006

Recent proteomic studies of protein domains require high-throughput and systematic approaches. Since most experiments using protein domains, the modules of protein-protein interactions, require gene cloning, the first experimental step should be retrieving DNA sequences of domain encoding regions from databases. For a large scale proteomic research, however, it is a laborious task to extract a large number of domain sequences manually from several inter-linked databases. We present a new methodology to retrieve DNA sequences of domain encoding regions through automatic database cross-referencing. To extract protein domain encoding regions, it traverses several inter-connected database with validation process. And we applied this method to retrieve all the EGF domain encoding DNA sequences of homo sapiens. This new algorithm was implemented using Python library PAMIE, which enables to cross-reference across distinct databases automatically.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.2
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• pp.12-17
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• 2003

This paper proposes content-based image retrieval system with fuzzy ART neural network algorithm. Retrieving large database of image data, the clustering is essential for fast retrieval. However, it is difficult to cluster huge image data pertinently, Because current retrieval methods using similarities have several problems like low accuracy of retrieving and long retrieval time, a solution is necessary to complement these problems. This paper presents a content-based image retrieval system with neural network in order to reinforce abovementioned problems. The retrieval system using fuzzy ART algorithm normalizes color and texture as feature values of input data between 0 and 1, and then it runs after clustering the input data. The implemental result with 300 image data shows retrieval accuracy of approximately 87%.

• Journal of Acupuncture Research
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• v.26 no.2
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• pp.147-158
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• 2009

Objectives : The purpose of this study is to review the recent research trends of evidence based medicine, especially human randomized controlled trials on acupuncture. Methods : The articles were collected by retrieving the database of Pubmed and Journal of Korean Acupuncture & Moxibustion Society. The retrieving period was from October 2003 to September 2008, and the search term was 'acupuncture'. The articles were classified according to their publication journals, countries, publication years, targeted diseases, types of acupuncture and types of control. Results : In total, 558 articles in Pubmed and 35 articles in Journal of Korean Acupuncture & Moxibustion Society were searched. The number of articles on acupuncture research has increased with higher rate since 2000, but the Qualitative development has not achieved the same amplitude. Studies in Korea were insufficient both in Qualitative and Quantitative aspects. In countries, China had the most papers, and in targeted diseases, pain diseases were most dominant. In the types of acupuncture, classical acupuncture, and in the types of control, conventional western treatment showed the highest frequency. Conclusions: We need to do many-sided and more high Quality researches on acupuncture. For that, well-designed randornized trials are absolutely necessary.