• The KIPS Transactions:PartC
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• v.13C no.5 s.108
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• pp.601-606
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• 2006

Decode-and-forward cooperative communications protocol (DFP) allows single-antenna users in wireless medium to obtain the powerful benefits of multi-antenna systems without physical antenna arrays. For this protocol, so far the relays have used SNR to evaluate the reliability of the received signal before deciding whether to forward the decoded data so as to prevent their unsuccessful detection. However, SNR only characterizes the long-term statistic of Gaussian noise and thus leading to inaccurate assesment. Therefore, we propose using log-likelihood ratio (LLR) which accounts for the instantaneous noise in the received signal as an alternative to SNR. A variety of simulation results reveal the significant superiority of the SNR-based DFP to the SNR-based DFP regardless of threshold level and relay position under the flat Rayleigh fading channel plus AWGN (Additive White Gaussian Noise).

• The KIPS Transactions:PartB
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• v.11B no.6
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• pp.683-690
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• 2004

Garment modeling and simulation is now one of the important elements in broad range of digital contents. Though there have been recent products on garment simulation, general users do not know well enough how to design a virtual costume that meets some requirements about its specific clothing pattern. In particular, Hanbok - the Korean traditional costume - has many different characteristics against western ones in the aspect of its pattern design and of draping. This paper presents a knowledge-driven approach for virtual Hanbok modeling without knowing how to make real Hanbok. First, parameterized knowledge for several fabric types art solicited using visual similarity assessment from simulated and real cloth. Secondly, based on the analysis of designer's knowledge, we defined multi-level adjustment processes of Hanbok measurements with regard to body shape features for different virtual actors. An experimental system is developed as the form of a Maya plug-in and the result shows the applicability of the proposed method.

• Journal of the Korea Computer Industry Society
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• v.2 no.4
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• pp.443-454
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• 2001

Software design patterns are reusable solutions to recurring problems that occur during software development. As programmers gain experience, they recognize the similarity of new problems to problems they have solved before. With even more experience, they recognize that solutions for similar problems follow recurring patterns. In this paper, as one of these reusable design-patterns, the Intermediator pattern for the efficient communication between business component is designed and implemented. Existent business components were way that follow Facade pattern. But Facade pattern is almost like the existing Interface pattern in that the communication of all the object outside the set is done by only one representative object, and this causes the traffic system to be overloaded. Therefore, the Intermediator pattern supplements the traffic overloads by improving the inefficient system of business components' communication through multi-interface, and make all communication behavior between objects done by Intermediator object which controls all actual behavior by way of Intermediator method implementation. Consequently, the Intermediator pattern is designed and implemented in this paper can bring down the level of coupling and raise the cohesion among objects, and refer to many of other object flexibly through several interfaces.

• Journal of Gifted/Talented Education
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• v.17 no.1
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• pp.77-98
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• 2007

It has been said that the level of teacher professionalism determines the quality of education. The same notion allies for gifted education. Therefore, exploration of teacher professionalism in gifted education may provide fundamental bases for raising the quality of gifted education. In this study, first, literature review was conducted to extract elements of teacher professionalism in gifted education and a survey instrument was developed to find out categories of those elements and differences of teacher perception to professionalism at school levels and subject areas of gifted education. Research subjects included 212 teachers who participated in 2005 KEDI teacher training program of gifted education, 60 hour-clock introductory program and 232 teachers who participated in 2005 KEDI teacher training program of gifted education, 120 hour-clock enrichment program. It was found that elements of teacher professionalism in gifted education were categorized into knowledge-based, abilitybased and context-based. It was also found that secondary school teachers' perception to knowledge-based professionalism was significantly higher than those at elementary and science teachers' perception to ability-based and context-based professionalism was significantly higher than mathematics teachers. The research findings may provide insights for better teacher training program in gifted education as well as gifted education policies.

• Journal of the Korea Convergence Society
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• v.11 no.6
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• pp.43-49
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• 2020

In spite of the notable advancements of millimeter wave communication technologies, the 60 GHz Wi-Fi is still not widespread yet, mainly due to the high limitation of coverage. Conventionally, it has been hardly possible to support a high data rate with fast beam adaptation while keeping atmospheric beamforming coverage. To solve these challenges in the 60 GHz communication system, holistic system designs are considered. we implemented an enhanced design LDPC decoder enabling 6.72 Gbps coded-throughput with minimal implementation loss, and our proposed phase-tracking algorithm guarantees 3.2 dB performance gain at 1 % PER in the case of 16 QAM modulation and LDPC code-rate 3/4.

• Journal of Environmental Science International
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• v.25 no.7
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• pp.1029-1042
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• 2016

The initial and boundary conditions are important factors in regional chemical transport modeling systems. The method of generating the chemical boundary conditions for regional air quality models tends to be different from the dynamically varying boundary conditions in global chemical transport models. In this study, the impact of real time Copernicus atmosphere monitoring service (CAMS) re-analysis data from the modeling atmospheric composition and climate project interim implementation (MACC) on the regional air quality in the Korean Peninsula was carried out using the community multi-scale air quality modeling system (CMAQ). A comparison between conventional global data and CAMS for numerical assessments was also conducted. Although the horizontal resolution of the CAMS re-analysis data is not higher than the conventionally provided data, the simulated particulate matter (PM) concentrations with boundary conditions for CAMS re-analysis is more reasonable than any other data, and the estimation accuracy over the entire Korean peninsula, including the Seoul and Daegu metropolitan areas, was improved. Although an inland area such as the Daegu metropolitan area often has large uncertainty in PM prediction, the level of improvement in the prediction for the Daegu metropolitan area is higher than in the coastal area of the western part of the Korean peninsula.

• Journal of the Korea Fashion and Costume Design Association
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• v.13 no.4
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• pp.1-14
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• 2011

This study is to analyze the image similarity and the preference for clothing stores in the 6 giant discount chains in Daejeon. The survey for this study was based on the questionnaires accomplished by 257 people through the multidimensional scaling. The results are as follows First, 6 clothing stores had 4 image groups located in 4 coordinates. CW(Costco Wholesale), NH(Nonghyup Hanaro-Mart), and SZ(Save Zone) had a similar distinct image, while HP(Home Plus) and EM(E-Mart), and LM(Lotte-Malt) also had similar differentiated images. Second, according to the preference analysis in terms of demographic characteristic, NH had the lowest preference from the people of all the different ages, while SZ had the highest. HP, EM, CW, and LM had their own preference in the following order: in the thirties, forties, and over fifties. Meanwhile, relatively, SZ is preferred by the people in their twenties and people over age fifty liked CW more. Third, according to the analysis of the preference for clothing stores in the giant discount chains in terms of educational background, clothing consumers who had high school degrees preferred NH and LM, people with 2 year college degrees liked HP and EM more, while 4-year college graduates and people with higher education had preference for SZ. Finally, according to the preference analysis in terms of income level, higher income groups preferred SZ and CW and lower income groups liked LH and LM more, while HP and EM had high preference from all kinds of income groups.

• Journal of Korean Institute of Industrial Engineers
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• v.39 no.1
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• pp.46-54
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• 2013

Recently, the marine leisure industry has begun to make a mark on the growth engines of the Korean economy. Hence, various government research projects are in progress to catch up with the fundamental yacht technologies of advanced countries. Research on the integrated management technologies of sail yachts is carried out as a part of those projects. Work Breakdown Structure (WBS) is a basic architecture for robust and high-level management systems. In this paper, we suggest a product-oriented Yacht Work Breakdown Structure (YWBS). General WBS has a drawback in that it can only follow the targeted purpose, but YWBS allows for a generic WBS approach. This concept allows us to apply WBS to multi-purpose uses. The YWBS is used as an infrastructure in information management and for data relationships in sail yacht management systems. YWBS is designed and managed by a web application, and the system is implemented with a website as a user interface. This application has not only a design function, but also a data transfer function that is based on the Microsoft Silverlight platform, a kind of Rich Internet Application (RIA) technology. Using this application, YWBS designers can communicate with the management system without added tasks like as uploading and updating.

• Journal of Korea Multimedia Society
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• v.7 no.9
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• pp.1219-1232
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• 2004

Recently, the web sites, such as e-business sites and shopping mall sites, deal with lots of catalog image information and contents. As a result, it is required to support semantic-based image retrieval efficiently on such image data. This paper presents a semantic-based image retrieval system, which adopts XML and Fuzzy technology. To support semantic-based retrieval on product catalog images containing multiple objects, we use a multi-level metadata structure which represents the product information and semantics of image data. To enable semantic-based retrieval on such image data, we design a XML database for storing the proposed metadata and study how to apply fuzzy data. This paper proposes a system, generate the fuzzy data automatically to use the image metadata, that can support semantic-based image retrieval by utilizing the generating fuzzy data. Therefore, it will contribute in improving the retrieval correctness and the user's satisfaction on semantic-based e-catalog image retrieval.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.6
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• pp.348-353
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• 2010

A threshold decryption scheme is a multi-party public key cryptosystem that allows any sufficiently large subset of participants to decrypt a ciphertext, but disallows the decryption otherwise. When performing a threshold decryption, a third party is often involved to guarantee fairness among the participants. To maintain the security of the protocol as high as possible, it is desirable to lower the level of trust and the amount of information given to the third party. In this paper, we present a threshold decryption scheme which allows the anonymity of the participants as well as the fairness by employing a semi-trusted third party (STTP) which follows the protocol properly with the exception that it keeps a record of all its intermediate computations. Our solution preserves the security and fairness of the previous scheme and reveals no information about the identities of the participants and the plaintext even though an attacker is allowed to access the storage of the STTP.