• Honam Mathematical Journal
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• v.31 no.3
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• pp.315-321
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• 2009

Erd$\"{o}$s posed the problem of determining the minimum number g(n) such that any set of g(n) points in general position in the plane contains an empty convex n-gon. In 1978, Harborth proved that g(5) = 10. We reprove the result in a geometric approach.

• Communications of the Korean Mathematical Society
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• v.32 no.3
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• pp.677-688
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• 2017

The composition of Jacobi type finite classes of the classical orthogonal polynomials with two generalized Riemann-Liouville fractional derivatives are considered. The outcomes are expressed in terms of generalized Wright function or generalized hypergeometric function. Similar composition formulas are also obtained by considering the generalized Riemann-Liouville and $Erd{\acute{e}}yi-Kober$ fractional integral operators.

• Honam Mathematical Journal
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• v.36 no.2
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• pp.455-465
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• 2014

In recent years, diverse inequalities involving a variety of fractional integral operators have been developed by many authors. In this sequel, here, we aim at establishing certain new inequalities involving pathway type fractional integral operator by following the same lines, recently, used by Choi and Agarwal [7]. Relevant connections of the results presented here with those earlier ones are also pointed out.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.11a
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• pp.163-170
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• 2002

해체 데이터베이스 구조 설계를 위하여 입력과 출력 항목 및 평가 대상 항목을 선정하였다. 해체 활동으로부터 발생되는 수많은 해체 정보들을 코드화하였다. 데이터베이스 구축에 사용되는 설계 도구들을 검토한 후 20 여가지 설계 도구들 중 범용적으로 사용되고 있는 모델링 도구를 이용하여 사용자 요구사항으로부터 도출된 주요 해체 정보들간의 관계를 ERD(Entity Relationship Diagram)를 사용하여 규명하였으며, DFD(Data Flow Diagram)를 이용하여 해체 DB 시스템의 프로세스 흐름을 파악하였다. 해체 데이터베이스 구현의 원할한 진행을 위해 프로토타입을 설계하였다.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.29.1-29.1
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• 2008

• Proceedings of the Korean Vacuum Society Conference
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• 2004.08a
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• pp.190-190
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• 2004

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.163-170
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• 2002

해체 데이터베이스 구조 설계를 위하여 입력과 출력 항목 및 평가 대상 항목을 선정하였다. 해체 활동으로부터 발생되는 수많은 해체 정보들을 코드화하였다. 데이터베이스 구축에 사용되는 설계 도구들을 검토한 후 20여가지 설계 도구들 중 범용적으로 사용되고 있는 모델링 도구를 이용하여 사용자 요구사항으로부터 도출된 주요 해체 정보들간의 관계를 ERD(Entity Relationship Diagram)를 사용하여 규명하였으며, DFD(Data Flow Diagram)를 이용하여 해체 DB 시스템의 프로세스 흐름을 파악하였다 해체 데이터베이스 구현의 원할 한 진행을 위해 프로토타입을 설계하였다.

• Journal of Biomedical Engineering Research
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• v.33 no.1
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• pp.15-24
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• 2012

Classification of human thought is an emerging research field that may allow us to understand human brain functions and further develop advanced brain-computer interface (BCI) systems. In the present study, we introduce a new approach to classify various mental states from noninvasive electrophysiological recordings of human brain activity. We utilized the full spatial and spectral information contained in the electroencephalography (EEG) signals recorded while a subject is performing a specific mental task. For this, the EEG data were converted into a 2D spatiospectral pattern map, of which each element was filled with 1, 0, and -1 reflecting the degrees of event-related synchronization (ERS) and event-related desynchronization (ERD). We evaluated the similarity between a current (input) 2D pattern map and the template pattern maps (database), by taking the inner-product of pattern matrices. Then, the current 2D pattern map was assigned to a class that demonstrated the highest similarity value. For the verification of our approach, eight participants took part in the present study; their EEG data were recorded while they performed four different cognitive imagery tasks. Consistent ERS/ERD patterns were observed more frequently between trials in the same class than those in different classes, indicating that these spatiospectral pattern maps could be used to classify different mental states. The classification accuracy was evaluated for each participant from both the proposed approach and a conventional mental state classification method based on the inter-hemispheric spectral power asymmetry, using the leave-one-out cross-validation (LOOCV). An average accuracy of 68.13% (${\pm}9.64%$) was attained for the proposed method; whereas an average accuracy of 57% (${\pm}5.68%$) was attained for the conventional method (significance was assessed by the one-tail paired $t$-test, $p$ < 0.01), showing that the proposed simple classification approach might be one of the promising methods in discriminating various mental states.

• Journal of the Korean Vacuum Society
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• v.13 no.1
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• pp.1-8
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• 2004

The SOI wafer fabrication technique has been developed by using ion-cut process, based on proton implantation and wafer bonding techniques. It has been shown by TRIM simulation that 65 keV proton implantation is required for the standard SOI wafer (200 nm SOI, 400 nm BOX) fabrication. In order to investigate the optimum proton dose and primary annealing condition for wafer splitting, the surface morphologic change has been observed such as blistering and flaking. As a result, effective dose is found to be in the 6∼$9\times10^{16}$ $H^{+}/\textrm{cm}^2$ range, and the annealing at $550^{\circ}C$ for 30 minutes is expected to be optimum for wafer splitting. The depth distribution of implanted hydrogen has been experimentally confirmed by ERD and SIMS measurements. The microstructure evolution in the damaged layer was also studied by X-TEM analysis.

• IE interfaces
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• v.15 no.4
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• pp.391-400
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• 2002

The internet call systems using CTI(Computer Telephony Integration) functions are designed with system configuration, DFD(Data Flow Diagram) and ERD(Entity Relationship Diagram) in this paper. The internet call systems are constructed to cooperate with conventional CTI call center. The internet phone calls occurred from the web browser of customer can be connected throughout VoIP gateway and PBX to many counselors. The internet call systems can provide various services; customer information service, escorted browsing service, text chatting service, text sharing service, conference service, and statistical analysis service.