• Journal of Navigation and Port Research
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• v.29 no.5 s.101
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• pp.377-382
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• 2005

A ship runs with various modes of motion due to waves. Among the modes, roll mainly influences on the safety of cargos on the deck of container ship. In order to protect cargo shifting and turning, securing and lashing system are generally installed. In that case, it is necessary that the force and moment at the connection point of containers should be estimated. Therefore we derived mathematical equations to calculate the forces of securing points and lashing wires. Also we calculated those forces and moments about various lashing patterns.

• Journal of Broadcast Engineering
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• v.8 no.2
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• pp.136-145
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• 2003

This paper proposes a DTV receiver using beamforming techniques to improve indoor and mobile reception. The proposed DTV receiver estimates the directions of arrival (DOAs) of incoming signals using Capon's DOA estimation method and generates an adaptive antenna beam pattern to the estimated DOA of the mainpath signal to Improve the channel condition. After beamforming, a following decision feedback equalizer (DFE) removes the remaining multipath components. The proposed receiver can be implemented with a conventional DTV receiver without anymodification. The performance of the proposed receiver is analyzed with modified Brazilian field test models, which include DOA information of Incoming signals. Simulation results show that the proposed receiver can satisfy the threshold of visibility (TOV) when input signal to noise ratio is slightly over 10 dB.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.2
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• pp.68-74
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• 2006

An experimental study was carried out to investigate the combustion characteristics of the slinger combustor. A combustion test rig was manufactured and installed in KARI combustor test facility. From the ignition test results, we found that there were two major factors influencing the ignition limits; by increasing the rotational speed and the air mass flow rate, a better ignition performance was attained. From the combustion test results, we obtained 99.6% combustion efficiency, 15% pattern factor, and 3% profile factor. The results in this work indicate that the ignition and combustion characteristics of a slinger combustor are markedly different from those of a conventional annular combustor.

• Journal of KIISE:Information Networking
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• v.37 no.6
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• pp.444-452
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• 2010

To avoid a channel zapping delay, the device needs to predict a next channel and must download it. Previous researches suggest algorithms based on assumption by utilizing many data. How to select and download future channels is a main issue in IPTV system. Most proposal based on assumption do not guarantees complete performance of channel zapping. In this paper, we suggest an effective method to avoid a channel zapping time with a constant performance by using a number remote controller key information.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.917-920
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• 2006

In mobile environments, their is more than one propagation path between each transceiver and Receiver have two or more delayed multipath signals. Delayed multipath signals can cause ISI and Receiver needs a adaptive algorithm to estimate a channel periodically. Also adaptive antenna using adaptive algorithm provide a significant increase in capacity, performance and coverage. This paper describes various LMS algorithm and evaluate the performance of array antenna Base station by using LMS algorithm in the presence of multipath signals and multiple users. As a result of simulation, Adaptive array antenna systems are able to adjust their antenna pattern to select desired signals, and reduce interference.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.189.2-189.2
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• 2013

1차원 산화아연 나노구조물은 광대역 에너지 밴드갭(~3.3 eV)과 독특한 물리적 특성을 갖고 있어, 전계효과 트랜지스터(field effect transistor), 발광다이오드(light emitting diode), 자외선 광검출기 (ultraviolet photodetector) 및 태양전지(photovoltaic cell)에 널리 이용되고 있다. 특히, 1차원 산화아연 나노구조물은 직접천이형 에너지 밴드갭(direct bandgap)을 갖고 있으며, 빛으로부터 여기된 전자가 1차원 나노구조물을 통해 향상된 이동경로를 제공할 수 있어서 차세대 자외선 광검출기 응용에 대한 연구가 활발히 진행되고 있다. 한편, 수열합성법(hydrothermal method)을 통해서 1차원 산화아연 나노구조물을 비교적 간단하고 저온공정을 통해서 합성할 수 있는데, 이를 광검출기 소자구조에 응용에서 양전극에 연결하기 위해서는 복잡하고 정교한 공정이 필요하다. 이에 본 연구에서는 수열합성법을 통해 합성된 산화아연 나노로드가 포함된 에탄올 용액을 금(Au) 패턴에 drop-casting을 통해서 간단한 방법으로 metal-semiconductor-metal (MSM) 광검출기를 제작하여 광반응 특성을 분석하였다. 또한 염료를 통해 가시광을 흡수하여 광전류(photocurrent)를 발생시킬 수 있도록 염료를 흡착한 산화아연 나노로드를 이용하여 같은 구조의 MSM 광검출기를 제작하여 가시광에 대한 광반응 특성을 관찰하였다.

• Journal of Internet Computing and Services
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• v.11 no.1
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• pp.103-116
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• 2010

In this paper, we propose an optimal camera placement using agent-based simulation. To derive importance of space and to cover the space efficiently, we accomplished an agent-based simulation based on classification of space and pattern analysis of moving people. We developed an agent-based camera placement method considering camera performance as well as space priority extracted from path finding algorithms. We demonstrate that the method not only determinates the optimal number of cameras, but also coordinates the position and orientation of the cameras with considering the installation costs. To validate the method, we compare simulation results with videos of real materials and show experimental results simulated in a specific space.

• Journal of Korea Multimedia Society
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• v.12 no.8
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• pp.1066-1072
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• 2009

This paper proposes a method to reduce the complexity and improve the performance for gentle-slope edges which is the disadvantage of deinterlacing algorithm using the new edge-directed interpolation. To improve the performance for gentle-slope edges, the proposed algorithm increases the number of neighboring reference pixels. To reduce the artifacts and the computational complexity, the proposed algorithm adaptively determines the number of neighboring reference pixels. With computer simulations for a variety of images, it shows that the proposed algorithm provides improved performance in PSNR and subjective evaluation compared with the existing algorithm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1089-1098
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• 2007

Currently, user require is diverse on the Web. Furthermore, each web user is wishing to retrieve data or goods that hey want to look for more conveniently and more quickly. Because different search criteria and dispositions of web users, they lead to unnecessary repeated operations in order to use implemented by web designer. In this paper, we suggest the system that analyzes user patterns on the Web using the technique of log file analysis and transfers more effectively the information of web sites to users. And we analyze the log file for customer data in the system the proposed method are implemented by means of EC-Miner that is one of the tool of datamining, and aims to offer appropriate Layout corresponding with personalization by giving weight to each transport path.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.1
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• pp.39-45
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• 2008

In this parer a branch type inverted-F structure antenna with dual-band is proposed. The proposed antenna has a size of about $70mm{\times}35mm{\times}0.8mm$ with a total mobile phone PCB for support and patch of about $12mm{\times}8mm{\times}0.8mm$. This antenna is designed to operate of frequency 2.45GHz and 5.8GHz, Bandwidth at each other frequency is satisfied $83MHz{\sim}100MHz$ in frequencies. Also, The designed and fabricated dual-band antenna for 2.45GHz, 5.8GHz have a gain between 2.0dBi and -1.0dBi at all bands.