• 한국전기전자재료학회논문지
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• 제24권5호
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• pp.410-415
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• 2011

In this paper, we investigated the fault current limiting and the load voltage sag suppressing characteristics of the flux-lock type SFCL, designed with the additive polarity winding, according to the variations of turn number's ratio and the comparative analysis between the resistive type and the flux-lock type SFCLs were performed as well. From the analysis for the short-circuit tests, the flux-lock type SFCL designed with the larger turn number's ratio was shown to perform more effective fault current limiting and load voltage sag suppressing operations compared to the flux-lock type SFCL designed with the lower turn number's ratio through the fast quench occurrence of the high-$T_C$ superconducting (HTSC) element comprising the flux-lock type SFCL. In addition, the recovery time of the flux-lock type SFCL after the fault removed could be confirmed to be shorter in case of the flux-lock type SFCL designed with the lower turn number ratio.

• Journal of the Korean Data and Information Science Society
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• 제24권3호
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• pp.543-555
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• 2013

이 연구는 프로골프대회에서 기록되는 중요변인들 (드라이브거리, 페어웨이안착율, 그린적중율, 센드세이브율, 리커버리율, 평균퍼팅수)이 평균타수에 미치는 영향력에 대해 집단 간 차이를 분석하였다. 구체적으로 미국남자프로골프협회 (PGA), 미국여자프로골프협회 (LPGA), 한국남자프로골프투어 (KGT), 그리고 한국여자프로골프투어 (KLPGT)에서 측정, 공개하는 자료를 통해 PGA, LPGA, KPGA, KLPGA 집단 간에 중요변인들이 평균타수에 미치는 경로에 유의한 차이가 있는지를 검증하였다. 그 결과 PGA와 LPGA 모형 간에 드라이브거리와 그린적중율이 평균타수에 미치는 경로가 p <.05 수준에서 통계적으로 유의한 차이가 있는 것으로 나타났으며, KPGA와 KLPGA 모형 간에는 드라이브거리, 리커버리율, 그리고 평균퍼팅이 평균타수에 미치는 경로가 유의한 차이가 있는 것으로 나타났다. 또한 PGA와 KPGA 모형 간에 드라이브거리, 리커버리율, 그리고 평균퍼팅이 평균타수에 미치는 경로가p <.05 수준에서 통계적으로 유의한 차이가 있는 것으로 나타났으며, LPGA와 KLPGA 모형 간에는 모든 경로에서 p >.05 수준에서 통계적으로 유의한 차이가 없는 것으로 나타났다. 이 연구 결과는 남녀 국내 투어와 미국 투어의 골프 경기력의 구조 특성을 이해하는데 필요한 기초자료로 활용 할 수 있을 것이며 향후 투어 진출을 위한 유의한 정보가 될 수 있을 것이다.

• Journal of information and communication convergence engineering
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• 제14권2호
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• pp.106-114
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• 2016

Differential sensing methods are more effective in alleviating panel noise than single-line sensing, and thus have been increasingly used in the touch screen industry. However, they have a drawback: they tend to cancel out multiple touches and need touch position recovery algorithms. This paper introduces a novel algorithm of touch position recovery for differential sensing, which is a low-complexity but high-accuracy approach for determining multiple touch positions. We have implemented the proposed method in a touch screen controller system on a chip. In the simulation experiments using realistic touch screen models and a differential sensing circuit, the algorithm exhibited a high detection performance of a signal-to-noise ratio gain of up to 52.21 dB. Therefore, we can conclude that the proposed method is substantially more accurate than the previous method. Further, the proposed method incurs little or no overhead in terms of the detection speed and the chip size.

• 한국물환경학회지
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• 제31권4호
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• pp.387-391
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• 2015

This study was performed to evaluate the effect of pH (8-12) and molar ratio of magnesium and phosphate ($[Mg^{2+}]/[PO_4{^{3-}}]$) (0.6-1.4) on struvite crystallization of anaerobic digester supernatant using seawater as magnesium source. pH range of 9-10 is favorable for ammonium and phosphate recoveries. The recovery efficiency of ammonium was highest at $[Mg^{2+}]/[PO_4{^{3-}}]$ of 1.0 and pH 10. On the other hand, high phosphate recovery efficiency (> 99%) was achieved at ($[Mg^{2+}]/[PO_4{^{3-}}]$) of 1.4 and pH 10. The results demonstrated that seawater can be considered as low-cost magnesium source to recover phosphorus from anaerobic digester supernatant.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권10호
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• pp.4160-4176
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• 2015

Data compression like image and video compression has come a long way since the introduction of Compressive Sensing (CS) which compresses sparse signals such as images, videos etc. to very few samples i.e. M < N measurements. At the receiver end, a robust and efficient recovery algorithm estimates the original image or video. Many prominent algorithms solve least squares problem (LSP) iteratively in order to reconstruct the signal hence consuming more processing time. In this paper non-iterative threshold based recovery algorithm (NITRA) is proposed for the recovery of images and videos without solving LSP, claiming reduced complexity and better reconstruction quality. The elapsed time for images and videos using NITRA is in ㎲ range which is 100 times less than other existing algorithms. The peak signal to noise ratio (PSNR) is above 30 dB, structural similarity (SSIM) and structural content (SC) are of 99%.

• Nuclear Engineering and Technology
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• 제55권2호
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• pp.674-680
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• 2023

The brine and seawater are important and largely untapped sources of critical trace metals and elements. The coupling of selective recovery of trace metals from seawater/brine with desalination plants gives an added advantage of energy credits to desalination plants and as well as reduce the cost of desalinated water. In this paper, status review on recovery of important trace metals and other alkali metals from seawater is presented. The potential of Indian desalination plants for recovery of trace metals, based on recovery ratio of 0.35 is also highlighted. Studies carried out by the process based on adsorption using Radiation Induced Grafted (RIG) polymeric adsorbents and then fractional elutions are presented. The fouling factors due to bio fouling and dirt fouling have been estimated for various locations of interest through field trails. The pay loader in the form of compact Contactor Assembly with minimum pressure drop, for loading specially designed radiation grafted sorbent in leaflet form has been briefed, as required for plant scale facility. The typical conceptual process design details of farm assembly of project CRUDE are described.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권9호
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• pp.522-529
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• 2002

In this paper, computer simulations of the physical Phenomena occurring in the arc region before and after current zero were carried out to evaluate the thermal recovery characteristics of a Laval nozzle. A commercial CFD program "PHOENICS" is used for the simulation and the user-coded subroutines to consider the arcing phenomena were added to this program by the authors. The computed results were verified by the comparison with the test results presented by the research group of GE Co.(General Electric Company). In order to investigate the state of the arc region after current zero, the simulation was carried out with three steps. They are steady state arc simulation, transient arc simulation before current zero, and transient hot-gas flow simulation after current zero. The semi-experimental arc radiation model is adapted to consider the radiation energy transport and Prandtl's mixing length model is employed as the turbulence model. The electric field and the magnetic field were calculated with the same grid structure used for the simulation of the flow field. The post-arc current was calculated to evaluate the thermal recovery characteristics after current zero. Compared with the results obtained by GE Co., it has been found that the critical RRRV(ratio of rise of recovery voltage) will be determined previously by this study.his study.

• 대한금속재료학회지
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• 제48권3호
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• pp.203-209
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• 2010

An application of the instrumented indentation technique has been expanded from the measurements of hardness and elastic modulus to the analysis of residual stress. A slope of the indentation loading curve increases (or decreases) according to compressive (or tensile) residual stress. A theoretical equation has been established for quantifying residual stress from the slope change. However, a precise observation of the remnant indents is indispensible because the theoretical approach needs actual contact information. In addition, the conventional hardness test is still used for predicting the residual stress distribution of welded joints. Thus, we observed the three-dimensional morphologies of the remnant indents formed on artificial stress states and analyzed stress effects on morphological recovery of the indents. First, a depth recovery ratio, which has been regarded as a sensitive stress indicator, did not show a clear dependency with the residual stress. Thus an analysis on volumetric recovery was tried in this study and yielded a inverse proportional behavior with the residual stress. In addition, an elastic to plastic volume recovery ratio showed more significant correlation with the residual stress.

• Journal of Information Processing Systems
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• 제14권2호
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• pp.510-522
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• 2018

As the major source of information, digital images play an indispensable role in our lives. However, with the development of image processing techniques, people can optionally retouch or even forge an image by using image processing software. Therefore, the authenticity and integrity of digital images are facing severe challenge. To resolve this issue, the fragile watermarking schemes for image authentication have been proposed. According to different purposes, the fragile watermarking can be divided into two categories: fragile watermarking for tamper localization and fragile watermarking with recovery ability. The fragile watermarking for image tamper localization can only identify and locate the tampered regions, but it cannot further restore the modified regions. In some cases, image recovery for tampered regions is very essential. Generally, the fragile watermarking for image authentication and recovery includes three procedures: watermark generation and embedding, tamper localization, and image self-recovery. In this article, we make a review on self-embedding fragile watermarking methods. The basic model and the evaluation indexes of this watermarking scheme are presented in this paper. Some related works proposed in recent years and their advantages and disadvantages are described in detail to help the future research in this field. Based on the analysis, we give the future research prospects and suggestions in the end.

• 한국관광식음료학회지:관광식음료경영연구
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• 제15권2호
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• pp.123-150
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• 2004

The purpose of this study is to prove that the approprlate fit between service failure and recovery strategy can effciently maximize customer satisfaction and behavioral intention, by using prepared scenario through comprehensive approach concerning how the expectation level about service recovery has influences on perceived fairness, satisfaction and behavioral intention of servlce recovery based upon size in case of service failure. This study has been conducted by way of selection of filling-up type questionnaires for customers themselves who have experience in service failure out of customers who can easily visit family and hotel restaurants, that is, domestic restaurants in Seoul area, June ~ August 2004, by setting factorial design of 2(control, severeness) ${\times}$ 3(distributive fairness, procedural fairness, mutual relational fairness) ${\times}$ 2(customer satisfaction, customer behavior). The survey was performed on the customers who visited common restaurants, family restaurants, hotel restaurants, etc. mainly in Seoul, and total 600 sheets of questionnaires were distributed and 496 sheets of them were returned(82.67% of return ratio).