• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.384-389
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• 2000

A artificial neural network model was developed to analyze and forecast the flow fluctuation at small streams in the Balan watershed. Backpropagation neural networks were found to perform very well in forecasting daily streamflows. In order to deal with slow convergence and an appropriate structure, two algorithms were proposed for speeding up the convergence of the backpropagation method, and the Bayesian Information Criterion(BIC) was proposed for obtaining the optimal number of hidden nodes. From simulations using daily flows at the HS#3 watershed of the Balan Watershed Project, which is 412,5 ㏊ in size and relatively steep in landscape, it was found that those algorithms perform satisfactorily.

• Journal of the Korean Professional Engineers Association
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• v.43 no.3
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• pp.23-27
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• 2010

Since 3DTV was introduced, the market could not grow further due to the several causes such as the lack of content, technology for production and display and eyestrain. However, the rapid advances of the technologies on digital broadcasting, consumer electronics and computer enabled the commercialization of 3D animation, computer graphic, 3D advertising as well as 3D movies, and since then the international technical competition is growing fiercer. Since much more companies introduced the solutions for 3D in NAB 2010 than 2009, the expected size of the market will be bigger than ever before. This article describes the recent trends and the prospect of the 3D technologies including national defence strategy, content, construction, consumer electronics, advertisement, and terrestrial 3D1V pilot project in Korea.

• Child Studies in Asia-Pacific Contexts
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• v.2 no.1
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• pp.45-60
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• 2012

This project examined 2, 3, and 4-year-old children (N = 34) in a university campus child care setting to assess their understanding of the graphic features they use in their emergent writing (to distinguish it from a drawing of the same referent). The graphic features present in samples of the children's work were examined and compared to the graphic features children could identify through verbal and nonverbal communication. We examined the frequencies of graphic feature identification, as well as significant differences between graphic feature usage and graphic feature identification. The most frequently used graphic features were linearity, unidirectionality, and small size of units. The most frequently identified graphic feature was conventional letter. Overall, children used significantly more graphic features than they were able to identify. Significant relationships comparing the 2-year-old group and 4-year-old group's usage and identification were also found. The findings are discussed in terms of their application to early childhood classrooms. Teachers can apply these findings when engaging children in conversations about their emergent writing; these discussions are explored as a beneficial teaching tool.

• Journal of electromagnetic engineering and science
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• v.11 no.3
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• pp.174-182
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• 2011

The On-line Electric Vehicle (OLEV) is an electric transport system in which the vehicle's power is transferred wirelessly from power lines underneath the surface of the road. Advantages of the OLEV include reducing battery size and cost to about 20 percent of that of conventional battery-powered electric vehicles, thereby minimizing the vehicle's weight and price, as well as the cost of charging the system. In this paper, we introduce a wireless power transfer mechanism to maximize the electrical performance of the power transfer system. Power transfer capacity, power transfer efficiency, and magnitude of leakage in the electromagnetic field (EMF) are analyzed, and the optimization methodology of the design parameters is discussed.

• The Journal of the Korean dental association
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• v.55 no.7
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• pp.468-480
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• 2017

A wide variety of benign and malignant lesions and other diseases can develop on oral mucosa. Oral mucosal lesions can also be associated with an underlying systemic disease, so their correct diagnosis, which may even share similar clinical and demographic features, is always a challenge for a dentist. Common oral mucosal lesions include candidiasis, herpes viral infection, leukoplakia, recurrent aphthous stomatitis, pemphigus, lichen planus and benign migratory glossitis. The differential diagnosis of these lesions are based on a thorough review of the patient's past medical and dental history and a complete oral examination. The knowledge of clinical features such as size, location, morphology, color, and pain is helpful in establishing a diagnosis. In addition, diagnostic tests, including microbiologic and laboratory tests and biopsies are usually required for establishing a proper diagnosis.

• Journal of Information Processing Systems
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• v.7 no.1
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• pp.151-158
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• 2011

Bivium is a simplified version of Trivium, a hardware profile finalist of the eSTREAM project. Bivium has an internal state size of 177 bits and a key length of 80 bits. In this paper, a guess and determine attack on this cipher is introduced. In the proposed method, the best linear approximations for the updating functions are first defined. Then by using these calculated approximations, a system of linear equations is built. By guessing 30 bits of internal state, the system is solved and all the other 147 remaining bits are determined. The complexity of the attack is O ($2^{30}$), which is an improvement to the previous guess and determine attack with a complexity of order O($2^{52.3}$).

• Proceedings of the KIEE Conference
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• 1998.11b
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• pp.685-688
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• 1998

In this research project, two aspects of small signal stability are studied: improvement in Hessenberg method to compute the dominant electromechanical oscillation modes and siting FACTS devices to damp the low frequency oscillation. Fourier transform of transient stability simulation results identifies the frequencies of the dominant oscillation modes accurately. Inverse transformation of the state matrix with complex shift equal to the angular speed determined by Fourier transform enhances the ability of Hessenberg method to compute the dominant modes with good selectivity and small size of Hessenberg matrix. Any specified convergence tolerance is achieved using the iterative scheme of Hessenberg method. Siting FACTS devices such as SVC, STACOM, TCSC, TCPR and UPFC has been studied using the eigen-sensitivity theory of augmented matrix. Application results of the improved Hessenberg method and eigen-sensitivity to New England 10-machine 39-bus and KEPCO systems are presented.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05b
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• pp.17-20
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• 2010

Recent Construction and Transportation R&D projects are larger in size, investment scale has been increasing rapidly. However, the results of Construction and Transportation in R & D are papers, patents and other results. So, the application record of R&D in the construction field is very lacking. In particular, Construction New Technology's ratio in the midst of R&D's results are about 2.29%. Therefore, this study suggested program that R&D's results has been connected Construction New Technology. The introduction of the new system has greatly increased Construction New Technology and the results of excellent &D will be applied in construction field. So, Cost-reduction and technology's improvement are expected.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.52
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• pp.297-309
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• 1999

Resource Constrained Dynamic Multi-Projects Scheduling(RCDMPS) is intended to minimize the total processing time(makespan) of two or more projects sequentially arriving at the shop under restricted resources. The aim of this paper is to develop the new Tabu Search heuristic for RCDMPS to minimize makespan. We propose the insertion method to generate the neighborhood solutions in applying the Tabu Search for the RCDMPS and the diversification strategy to search the solution space diversely. The proposed diversification strategy apply the dynamic tabu list that the tabu list size is generated and renewed at each iteration by the complexity of the project, and change the proposed tabu attribute. In this paper, We use the dynamic tabu list for the diversification strategy and intensification strategy in the tabu search, and compare with other dispatching heuristic method to verify that the new heuristic method minimize the makespan of the problem.

• Journal of the Microelectronics and Packaging Society
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• v.9 no.1
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• pp.15-20
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• 2002

In this project, we hale developed various techniques for subminiaturization, surface implementation, high frequency design, small-size SMD, performance test and application of the Dual PLL module, which is a core component for the personal communication systems. We also obtained base techniques for the next-generation Dual PLL module design and fabrication techniques for an internationally competitive subminiature Dual PLL module.