• The Transactions of the Korea Information Processing Society
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• v.6 no.8
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• pp.2020-2030
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• 1999

Data acquired about 53 gigabyte per a naval vessel is massive, expensive and impossible to be retested in a underwater acoustic measurement. So, it is required to manage systematically. In this paper, we mention MUADS (Massive Underwater Acoustic Database System) that was developed to store a long time, manage systematically and supply raw data and analyzed data. we analyze client/server performance based on 6003 input data individually in our MUADS that Unix server having a massive DC-jukebox and Windows clients.

• Journal of Internet Computing and Services
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• v.8 no.6
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• pp.127-133
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• 2007

The u-learning environment has been developed through a number of iterations, and has now been formally evaluated, through analysis of student learning results and the use of quantitative and qualitative measures, Generally, for advance learning effect and analysis of student learning results, the most learning system be use to the item analysis method. But, nowadays, it has using the IRT(Item Response Theory) instead of the item analysis method, The IRT adopts explicit models for the probability of each possible response to a test. Therefore, I proposed the lightweight component based u-learning system using the IRT. Applied device of u-learning is PDA which is in Windows mobile 5.0 environments.

• Journal of Radiation Protection and Research
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• v.12 no.1
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• pp.12-25
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• 1987

A basic multichannel analyser (MCA) system have been designed and constructed with the successive approximation type ADC (Analog to Digital Converter). Linear Gate, window, and palse stretcher consist of mainly linear and logic IC's, and are properly combined together to achieve short dead time and good linearity of the system. ADC 1211 (analysing time: $120{\mu}sec$) and S-RAM (static random acess memory) 6264 are used in ADC module. Two 6264 memories are connected in parallel in order to-provide enough counting capacity ($2^{16}-1$). Interfaced microcomputer Apple II controls this system and analizes the counted data. The system is tested by input pulses between 0V to 10V from oscillator.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.6
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• pp.1204-1211
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• 2004

As the development of information telecommunication technology and thus the information sharing and opening is accelerated, f system is exposed to various threatener and the avrious security incident is rasing its head with social problem. As countermeasure, to protect safely and prepare in the attack for a system from a be latent security threat, various security systems are been using such as IDS, Firewall, VPN etc.. But, expertise or expert is required to handle security system. The module, implemented in this paper, is based on Windows XP, like Linux and Unix, and has effect integrity and non-repudiation for a file.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.8
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• pp.371-378
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• 2002

This paper presents the rapid and accurate algorithm for fault detection and location estimation in the transmission line. This algorithm uses wavelet transform for fault detection and harmonics elimination and utilizes least square error method for fault impedance estimation. Wavelet transform decomposes fault signals into high frequence component Dl and low frequence component A3. The former is used for fault phase detection and fault types classification and the latter is used for harmonics elimination. After fault detection, an adaptive data window technique using LSE estimates fault impedance. It can find a optimal data window length and estimate fault impedance rapidly, because it changes the length according to the fault disturbance. To prove the performance of the algorithm, the authors test relaying signals obtained from EMTP simulation. Test results show that the proposed algorithm estimates fault location within a half cycle after fault irrelevant to fault types and various fault conditions.

• Convergence Security Journal
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• v.10 no.1
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• pp.1-8
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• 2010

Recently, the number of internet users using smartphone is increasing worldwide, and the interest in the smartphone malware is increasing. Especially, since mobile malware are occurring to the smartphones using Symbian or Windows Mobiles in the abroad, it is necessary to have an action plan against these mal wares. This paper describes the possible security threat through the analysis of the mal wares occurred after 2004. Also we present a model for the future propagation prevention system which can cope with domestic smartphone mal wares.

• Journal of Digital Contents Society
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• v.8 no.4
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• pp.579-586
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• 2007

The process of developing a online 3D game engine involves designing details of the engine, alpha test, adjustment, supplementation, beta test and introduction, and an online 3D game engine is made of a server engine and client engine. The server engine, which is made of server construction part, distribution center and DB construction part for building asymmetric multiple servers, is developed by Linux, and the client engine, which is made of a graphic part, sound part, AI part and object management part, is developed by using DirectX in Windows, and it proposes an engine configuration and method based on 3D engine technology by analyzing the network technology, which is a common engine technology.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1530-1536
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• 2007

In this paper, a mobile banking system which can provide banking services is introduced. Since a PDA has excellent features like a small-size computer and provides mobility, it has been widely used by salesmen. Therefore, if general banking services can be provided with PDA by using wireless technology, it will be very useful. In addition, it is easy to develop and maintain the client software of PDA because it uses Windows-based operation systems. In this paper, a PDA banking system is introduced. The system is designed and developed based on the techniques of wireless network, security and PDA programming to be used for mobile banking and a prototype system is developed. Moreover, we used the object-oriented modeling technique, UML and Java Beans for programming.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.2
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• pp.22-28
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• 1994

A data acquisition and processing system. using an IBM PC, an AD converter, and a printer, has been developed to monitor rapidly and significantly varying signals. The sister takes live signals and computes and displays the trend of the moving averages of the signals in real time. The system has been applied to monitor the shaft horsepower and revolution and the speed of ships for their speed trial. The reliable interpretation of the measured data using moving average can eliminate unnecessary arguments between the owner and yard on the performance of the newly built ships. Other applications of the system-inspection of engine hunting, providing data for ship maneuvering analysis, vibration data analysis, extending to the ship performance monitoring system-are also demonstrated and discussed.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.597-597
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• 2015

기후변화에 따른 홍수 위험도 증가와 태풍 및 집중호우의 증가는 도시지역의 홍수로 인한 피해가 커지고 있다. 실제로 최근 10년간 홍수로 인한 재산피해 및 인명피해는 해마다 늘고 있다. 이러한 홍수피해를 최소화 할 수 있는 도시지역 초단기 강우 예보 시스템 개발은 필수적이다. 그동안 기상레이더를 이용한 강우예측 모형은 국내외적으로 많이 개발이 되어 있지만, 위성을 이용한 단기간 강우예보모형은 많이 부족한 실정이다. 최근 국내 최초 기상위성의 발사로 위성을 이용한 강수관측 및 초단기 예보가 가능하게 되었다. 이러한 초단기 강우 예보 시스템의 기본예측모형인 구름이동벡터를 개발하기 위해서 본 연구에서 COMS 위성자료를 이용하였다. COMS 위성은 2011년 4월에 발사되어 현재 운영 중에 있다. COMS 위성 자료는 현재 일본 정지궤도 위성 MTSAT 위성자료와 달리 한반도 영역을 대상으로 적외채널 자료들을 8-15분 간격으로 수집 가능하여 집중호우 예보에 매우 유리하다. COMS 위성의 연속되는 위성 구름의 교차상관을 통해서 이동벡터를 산출하여 예측 모형을 산출하였다. 교차상관 기법은 연속되는 구름 자료에 대해서 두 윈도우 사의 상관계수의 최대치를 찾아냄으로써 구름의 이동방향과 이동속도를 산출하는 방법이다. 기 개발된 예측모형을 이용하여 한반도 지역의 이동벡터를 산출하였으며, 본 연구에서 산출된 구름이동벡터는 도시지역의 갑자기 발생하는 집중호우나 태풍의 초단기 예측의 기본 모형으로 탑재될 것이다.