• 한국통신학회논문지
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• 제22권5호
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• pp.1097-1106
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• 1997

Most works on importance sampling (IS) as an efficient evaluation technique havd been done in an additibe white gaussian noise channel (Awgn). In this paper we propose a CQ(conventional importance sampling and quasi-translantion) IS technique for the mobile radio channel modeled as Rician fading, and analyze the IS estimator's variance to determine optimum IS parameters and the minimum number of run times. Reference showed that CIS technique has a poor performance for systems with meories, but it is shown that the CIS technique can be improved by combining with quasi-translation technique even for systems with memories. Here the CQ IS technique modifies the variance of additive noise and also performs quasi-translation for the fading distribution. We determine the optimum IS parameters of the proposed CQ IS estimator and whow that the simulation gains are about 10$^{3}$~10$^{6}$ for the mobile communication systems with memories in case of the expected BERs 10$^{-5}$ ~10$^{-8}$ .

• International Journal of Internet, Broadcasting and Communication
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• 제11권1호
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• pp.85-88
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• 2019

In this paper, we propose a technique for spatially encrypting confidential data into R, G, B planes of color image and extracting spatially encrypted confidential data. The effectiveness of the proposed technique is verified by mathematically analyzing the quality of the stego-image generated using the proposed technique. The proposed technique can hide confidential data securely into cover image by spatially encrypting the confidential data, and can extract confidential data from the stego-image. The quality of the stego-image created by applying the proposed technique is very good. The average value of the quality of the stego-image is 51.14 dB. Therefore, it is not visually recognizable whether the confidential data is hidden in the stego-image. The proposed technique can be widely used for military and intellectual property protection.

• Journal of Power Electronics
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• 제19권2호
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• pp.413-430
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• 2019

This paper presents an optimum hybrid SVPWM technique for three-level voltage source inverters (VSIs). The proposed hybrid SVPWM technique aims to minimize total harmonic distortion (THD). A new parameter is introduced to incorporate the heterogeneous nature of switching sequences of SVPWM technique. The proposed hybrid SVPWM technique is implemented on a low-cost PIC microcontroller (PIC18F452) and verified experimentally with a 2 KVA three-phase three-level insulated gate bipolar transistor-based VSI. Optimum switching sequence results in the three-level inverter configuration are demonstrated. The proposed hybrid SVPWM technique improves the THD performance by 17.3% compared with the best available three-level SVPWM technique.

• International journal of advanced smart convergence
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• 제9권4호
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• pp.86-95
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• 2020

There is a unique method of musical expression in the nature documentary. The expression method is Mickey Mousing technique, which expresses the movement of animals with music. The Mickey mousing technique can also be used in other types of documentaries, but it is most prominently used in nature documentaries. The Mickey Mousing technique cannot be used in any field other than music composition, because the composer should describe the movement of animals by playing music to match the animal's movements exactly. It is also because they have to play the instrument separately according to the sound source. In this study, we examined the nature documentaries broadcast by KBS over the last five years and analyzed the cases of Mickey Mousing technique. Therefore, we obtained research results that the Mickey Mousing technique is necessary and that the music composition is also necessary as a background music of nature documentaries.

• 대한임베디드공학회논문지
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• 제17권6호
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• pp.329-335
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• 2022

In this paper, we study the effect of noise on video inpainting, a technique that fills missing regions of video. Since the video may contain noise, the quality of the video may be affected when applying the video inpainting technique. Therefore, in this paper, we compare the inpainting performance in video with and without denoising techniqueDAVIS dataset. For that, we conducted two experiments: 1) applying inpainting technique after denoising the noisy video and 2) applying the inpainting technique to the video and denoising the video. Through the experiment, we observe the effect of denoising technique on the quality of video inpainting and conclude that video inpainting after denoising would improve the quality of the video subjectively and objectively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권11호
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• pp.3658-3679
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• 2022

Classification of persons wearing and not wearing face masks in images has emerged as a new computer vision problem during the COVID-19 pandemic. In order to address this problem and scale up the research in this domain, in this paper a hybrid technique by employing ResNet-101 and multi-layer perceptron (MLP) classifier has been proposed. The proposed technique is tested and validated on a self-created face masks classification dataset and a standard dataset. On self-created dataset, the proposed technique achieved a classification accuracy of 97.3%. To embrace the proposed technique, six other state-of-the-art CNN feature extractors with six other classical machine learning classifiers have been tested and compared with the proposed technique. The proposed technique achieved better classification accuracy and 1-6% higher precision, recall, and F1 score as compared to other tested deep feature extractors and machine learning classifiers.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1998년도 학술발표대회 논문집 제17권 1호
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• pp.239-242
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• 1998

A new real time sound field visualization technique is introduced in this study using PIV(Particle Imaging Velocimetry) technique. Small particles of which density is small enough to follow up the air flow are used for sound visualization. When the driving frequency is in the vicinity of the resonance frequency of the simplified 2-dimensional muffler system, an acoustic streaming is shown and of which velocity distribution is obtained through PIV technique. It is experimentally proved that the present technique is able to visualize and quantify the sound field's energy flow.

• 척추신경추나의학회지
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• 제3권1호
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• pp.49-54
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• 2008

This study is designed to evaluate the effect of HyunGa manual technique for the patient with scoliosis. After HyunGa manual technique the results of cobb's angle were improved significantly. It is suggested that HyunGa manual technique might be effective for the patiant with Scoliosis.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.442-447
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• 2005

This paper presents an application of overlapping-grid technique for probe feeding simulation. The overlapping grid technique is used to solve contour path problem. In this technique, field interpolation is very important to make communication between two coordinates. By applying overlapping-grid technique, error of contour path in probe feeding simulation is reduced.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 전력전자학술대회 논문집
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• pp.171-174
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• 1998

The development of the high-frequency induction-heating for 2700kW power range intend to make localization at forging and rolling mill part by technical innovation. And, the development makes to increase our's competitive power at technique, quality and cost. This paper describes the heart of high-frequency induction-heating technique, switching technique, a few problem in common using as an unsatisfied technique, load adjustment technique, system control, diagnostic system, and auto-interface etc.