• Journal of Astronomy and Space Sciences
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• v.18 no.1
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• pp.27-32
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• 2001

A statistical study has been performed of the magnetic storm recovery phase using the Dst index for 102 storm events in the interval January 1996 to December 1998. In 43 cases (or 42%) out of our 102 events, the recovery phase exhibits fast recovery (kaking about 8 hours or less) at its initial stage or for the entire recovery period. Since this fast recovery can be explained by the fast charge exchange less of $O^{+}$ ions which mostly com from the ionosphere, and since a fraction of $H^{+}$ ions is of ionospheric origin as well, our statistical result supports the view that the source of ring current ions in many magnetic storms can be terrestrial.

• The Journal of Korea Robotics Society
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• v.2 no.1
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• pp.29-39
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• 2007

We present an implementation of particle filter algorithm for global localization and kidnap recovery of mobile robot. Firstly, we propose an algorithm for efficient particle initialization using sonar line features. And then, the average likelihood and entropy of normalized weights are used as a quality measure of pose estimation. Finally, we propose an active kidnap recovery by adding new particle set. New and independent particle set can be initialized by monitoring two quality measures. Added particle set can re-estimate the pose of kidnapped robot. Experimental results demonstrate the capability of our global localization and kidnap recovery algorithm.

• Review of KIISC
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• v.7 no.4
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• pp.45-58
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• 1997

본고에서는 현재 여러 국가와 기업에서 논의되고 있는 Key Recovery시스템이 제안된 배경과 미국에서의 시행 정책과 현황 등을 살펴보고 Key Recovery시스템을 구성하는 주요 요소와 실제 시스템의 구현시에 고려되어야 할 부분들을 보다 일반적인 관점에서 논의하고자 한다.

• Journal of Sericultural and Entomological Science
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• v.28 no.1
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• pp.61-65
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• 1986

This work was to realize the wrinkling behavior of spun silk fabric. The results were obtained through the various conditions such as temperature, wrinkling time, wrinkling load and crease recovery time. The obtained results were summerized as follows : 1. Wrinkle recovery of the silk fabric was decreased with the increase of temperature, humidity and the influence of humidity was superior to the influence of temperature. 2. The change of wrinkle recovery depending on the wrinkle recovery time showed the experimental equation (Y=a+b lnT). The wrinkle recovery increased with the lapse of wrinkle recovery time but arrived at the equilibrium position about 300 sec. 3. The value "K1" of the silk fabric in the "Voigt model" was inferior as compared with the polyester and Nylon. 4. The change of wrinkle recovery depending on the wrinkling time was decreased with the lapse of wrinkle recovery time but the change of the value "a" could not be fined. 5. The change of wrinkle recovery depending on the wrinkling load was same as above 4.

• Journal of Periodontal and Implant Science
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• v.49 no.2
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• pp.127-135
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• 2019

Purpose: The aim of this study was to evaluate the computed tomography (CT) imaging findings and clinical symptoms of patients who complained of neurosensory disturbances after mandibular implant surgery, and to investigate the relationships of these parameters with the prognosis for recovery. Methods: CT scans were reviewed in 56 patients with nerve disturbance after mandibular implant surgery. Two oral radiologists classified the imaging findings into intrusion, contact, close, and separate groups according to the distance from the inferior border of the implant to the roof of the mandibular canal (MC). The symptoms of 56 patients were classified into 8 groups and the frequency of each group was investigated. Patients were categorized according to symptom improvement into no recovery and recovery groups, and the relationships of recovery with the CT classification and specific symptom groups were analyzed. Results: Thirty-eight of the 56 nerve disturbance cases showed improvement. The close and separate groups in the CT classification had a strong tendency for recovery (90.9% and 81.8%, respectively) (P<0.05). Although the lowest recovery rate was found in the intrusion group, it was non-negligible, at 50%. The 6 patients with a worm crawling feeling all improved, while the 8 cases with a tightening sensation showed the lowest recovery rate, at 12.5%, and the symptom of a tightening sensation occurred only in the intrusion and contact groups. Conclusions: The closer the implant fixture was to the MC on CT images, the less likely the patient was to recover. Regarding paresthesia symptoms, while a worm crawling feeling is thought to be a predictor of recovery, a tightening sensation appeared to be associated with a lower recovery rate.

• Journal of Information Technology Applications and Management
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• v.23 no.4
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• pp.25-39
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• 2016

Asset prices decline sharply and stock markets collapse when financial crisis happens. Recently we have encountered more frequent financial crises than ever. 1998 currency crisis and 2008 global financial crisis triggered academic researches on early warning systems that aim to detect the symptom of financial crisis in advance. This study proposes a risk recovery index for detection of good opportunities from financial market instability. We use SVM classifier algorithms to separate recovery period from unstable financial market data. Input variables are KOSPI index and V-KOSPI200 index. Our SVM algorithms show highly accurate forecasting results on testing data as well as training data. Risk recovery index is derived from our SVM-trained outputs. We develop a trading system that utilizes the suggested risk recovery index. The trading result records very high profit, that is, its annual return runs to 121%.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.54-62
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• 2003

This paper surveys a number of remotely operated recovery techniques and their recent applications in the removal of the toxic liquid from sunken ships, and suggests the appropriate recovery technique for our ocean environment, especially, in view of its cost and efficiency. Authors also give the technical requirements for the suggested remotely operated recovery system and the basic design result which is well-matched with such requirements.

• Journal of Korean Society for Quality Management
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• v.41 no.1
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• pp.95-108
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• 2013

Purpose: The purpose of this study is to identify the impact of TQM dimensions through service recovery justice on service quality and customer satisfaction. Methods: This study employed structural equation modeling methodology analyzing 265 samples collected. Results: This study found that TQM related factors had positive influence on service recovery justice in general. In specific, top management leadership and employee participation are the most important factors for the service recovery justice. Conclusion: This study reveals that service recovery justice has the positive impact on both service quality and customer satisfaction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4C
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• pp.371-376
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• 2010

In this paper, we propose a new fast carrier recovery algorithm for high-order QAM systems. The proposed algorithm detects carrier frequency offset from the phase differences among the received symbols directly and combines it with the conventional carrier recovery, so that it is possible to achieve the carrier recovery with wide tracking range and fast acquisition time. Simulation results show that the proposed carrier recovery method reduces acquisition time at large frequency offset and low signal-to-noise ratio (SNR).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.8
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• pp.690-696
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• 2003

This paper presents the heat recovery performance of water fluidized-bed heat exchanger. Temperature and humidity ratio of waste gas are considered as important parameters in this study. Therefore, the heat recovery rate through water fluidized-bed heat exchanger for exhaust gases with various temperatures and humidity ratios can be estimated from the results of this study. Mass flow ratio (the ratio of mass flow rate of water to that of gas) and temperature of inlet water are also considered as important operating variables. Increase of heat recovery rate can be obtained through either high mass flow ratio or low temperature of inlet water with resultant low recovered temperature. The heat recovery performance with the mass flow ratio of about up to 10 has been investigated. The effect of number of stages of water fluidized-bed on the heat recovery performance has been also examined in this study.