• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.237-243
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• 2004

A multichannel smart sound sensor capable to detect and identify sound events in noisy conditions is presented in this paper. Sound information extraction is a complex task and the main difficulty consists is the extraction of high­level information from an one-dimensional signal. The input of smart sound sensor is composed of data collected by 5 microphones and its output data is sent through a network. For a real time working purpose, the sound analysis is divided in three steps: sound event detection for each sound channel, fusion between simultaneously events and sound identification. The event detection module find impulsive signals in the noise and extracts them from the signal flow. Our smart sensor must be capable to identify impulsive signals but also speech presence too, in a noisy environment. The classification module is launched in a parallel task on the channel chosen by data fusion process. It looks to identify the event sound between seven predefined sound classes and uses a Gaussian Mixture Model (GMM) method. Mel Frequency Cepstral Coefficients are used in combination with new ones like zero crossing rate, centroid and roll-off point. This smart sound sensor is a part of a medical telemonitoring project with the aim of detecting serious accidents.

• 한국통신학회논문지
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• 제22권10호
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• pp.2329-2338
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• 1997

A conventional digital receiver sampled a baseband signal and processed it digitally for demodulation. But now we can sample at sufficiently high speed a wideband signal to take enough discrete data values due to the advent of economic high-speed ADC. With this technical background, a wideband frequency-division-multiplexed signal can be undersampled and channelized in digital domain by DFT analysis filter using the theory of polyphase. In this paper, we propose a new digital receiver which can digitally process the multichannel received signal by sampling at IF band, develop a mathematical theory and algorithm, and analyze the performance by using C-language simulaation. The proposed receiver can demodulate analog and digital FM signals.

• 한국의상디자인학회지
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• 제22권2호
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• pp.1-18
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• 2020

The purpose of this study is to investigate the consumers' characteristics in terms of information source usage and purchase channel choice focusing on apparel purchasers in the multichannel retailing environment. The specific research objects are as follows: analyzing consumer's information source usage and purchase channel choice when buying their own clothing, examining the differences of consumers' characteristics according to the groups who are classified by their information source usages, and examining the differences of consumers' characteristics according to the purchase channel choice. The data was collected from adults over 20 years of age who had bought their own clothing within the last year. The questionnaire was carried out during September 2019, using a professional internet research panel, and 490 useful data sets were analyzed by utilizing descriptive statistics, factor analysis, reliability analysis, chi-squared test, ANOVA and a Duncan-test using SPSS 21.0. The findings showed that there were also significant differences of consumers' characteristics which included age, gender, monthly clothing expenditure, purchase price, shopping value and perceived risk according to the consumer's information source usage and their purchase channel choice.

• Journal of Radiation Protection and Research
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• 제12권1호
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• pp.12-25
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• 1987

SA(Successive Approximation)형 ADC(Analog to Digital Converter)를 사용하여 방사선다중채널파고 분석기를 설계 제작하였다. 선형게이트, 윈도우 및 펄스스트레처는 논리 IC와 선형 IC들을 위주로 결합하여 구성하였으며, 분석시간이 $120{\mu}sec$인 ADC 1211(12 bit)을 중심으로 한 ADC 모듈의 메모리로는 S-RAM 6264 (Address 13 bit, Data 8 bit) 2개를 병렬로 연결하여 사용하였다. 마이크로 컴퓨터 (Apple II)가 전체 시스템을 제어하고 또 계측된 결과의 데이타를 분석할 수 있도록 인터페이스와 소프트 웨어도 만들었다. 제작된 시스템의 동작시험은 표준펄스 발생기로 $0{\sim}10V$ 사이의 일정한 펄스를 만들어 시스템에 입력시켜 그 펄스들을 계측하게 하고, 계측이 끝난 후 컴퓨터가 그 결과를 받아들여 분석하게 함으로써 이루어졌다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2116-2119
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• 2003

In this paper, we present a DirectShow-based retrieval and playback subsystem of DVR(Digital Video Recorder), which supports real-time playback of stored video data and synchronized playback among several video channel data. The effectiveness of out proposed design is verified through experiments with a DVR system implementing the proposed design.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (2)
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• pp.232-234
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• 2002

EEG-based brain computer interface (BCI) provides a new communication channel between human brain and computer. The classification of EEG data is an important task in EEG-based BCI. In this paper we present methods which jointly employ principal component analysis (PCA) and linear dynamical system (LDS) modeling for the task of EEG classification. Experimental study for the classification of EEG data during imagination of a left or right hand movement confirms the validity of our proposed methods.

• 인터넷정보학회논문지
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• 제16권2호
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• pp.1-6
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• 2015

본 논문에서는 고품질 멀티미디어 데이터를 IEEE 802.1 Audio Video Bridging 기반의 네트워크를 통해 스마트 자동차와 스마트 홈 및 스마트 공연장에서 실시간으로 송수신할 수 있는 임베디드 플랫폼을 설계를 통해 정밀한 시간 동기화 표준인 IEEE 802.1AS와 QoS 보장을 위한 자원할당 표준인 IEEE 802.1Qat 프로토콜 분석을 통해 성능을 검증한다. 이를 위해 MRP(Multiple Registration Protocol), MMAP(Multicast Address Acquisition Protocol), IEEE 1722, 1722.1 등 AVB의 핵심 Layer-2 프로토콜을 리눅스 운영체제를 기반으로 구현한다. 아울러 상용 AVB 엔드포인트와 연동 실험을 통해 상호 호환성 및 멀티미디어 스트림의 실시간 송수신이 가능함을 보인다.

• 한국유통학회지:유통연구
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• 제13권3호
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• pp.27-54
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• 2008

본 연구는 가정 내 유통업체(In-home shopping channel)의 다채널 고객관리에 시사점을 제공하기 위하여 가정 내 쇼핑채널로서 TV, 카탈로그 및 인터넷 쇼핑채널 간 소비자의 정보탐색과 구매행동과의 관계를 고찰하였다. 가정 내 쇼핑채널들의 정보탐색과 구매행동과의 관련성을 채널 내 고객 고정(channel lock-in)과 채널 간 시너지(cross-channel synergy)로 구분하여 영향력을 비교 평가하였다. 이를 위하여 1개월 동안의 가정 내 쇼핑채널 이용에 대한 자료를 345명의 가정주부를 대상으로 수집하였다. 소비자의 구매채널 이용행동을 선택, 빈도 및 지출행동으로 구분하여 분석을 수행만 결과 가정 내 쇼핑채널 간 정보탐색과 구매행동 간에는 높은 채널 내 고객 고정 효과가 나타나고 있으며 낮은 채널 간 시너지 효과가 나타나고 있었다. 또한 TV 채널의 경우 카탈로그와 인터넷 채널 간 대체성이 나타나는 반면에 카탈로그와 인터넷 채널은 보완성이 나타나고 있다. 이러만 결과는 가정내 다채널 유통기업에게 채널 간 조정과 통합 및 고객관리에 많은 시사점을 제공하고 있다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2006년도 공동학술대회 논문집
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• pp.17-22
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• 2006

Shear modulus is directly linked to material's stiffness and is one of the most critical engineering parameters. Seismically, shear-wave velocity (Vs) is its best indicator. Although methods like refraction, down-hole, and cross-hole shear-wave surveys can be used, they are generally known to be tougher than any other seismic methods in field operation, data analysis, and overall cost. On the other hand, surface waves, commonly known as ground roll, are always generated in all seismic surveys with the strongest energy, and their propagation velocities are mainly determined by Vs of the medium. Furthermore, sampling depth of a particular frequency component of surface waves is in direct proportion to its wavelength and this property makes the surface wave velocity frequency dependent, i.e., dispersive. The multichannel analysis of surface waves (MASW) method tries to utilize this dispersion property of surface waves for the purpose of Vs profiling in 1-D (depth) or 2-D (depth and surface location) format. The active MASW method generates surface waves actively by using an impact source like sledgehammer, whereas the passive method utilizes those generated passively by cultural (e.g., traffic) or natural (e.g., thunder and tidal motion) activities. Investigation depth is usually shallower than 30 m with the active method, whereas it can reach a few hundred meters with the passive method. Overall procedures with both methods are briefly described.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제24권3호
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• pp.256-264
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• 2021

Purpose: Data on the relationship between gastroesophageal reflux (GER) and brief resolved unexplained events (BRUE) in infants is scarce. The aim of this study was to identify the characteristics of combined multichannel intraluminal impedance-pH (MII-pH) monitoring in infants who have experienced BRUE. Methods: We conducted a prospective study of infants who were hospitalized on account of BRUE and required 24-hour MII-pH monitoring. Results: Twenty-one infants (mean age, 4.7 months; range, 0.9-8.9 months; male/female, 11/10) participated in this study. BRUE symptoms associated with GER were found in 10 infants (47.6%). Based on the RI on pH-metry alone, only 7 (33.3%) infants were diagnosed with GERD. More than 100 GER episodes detected by MII were found in 10 (47.6%) infants. Nineteen percent of infants were diagnosed with GERD based on both pH and MII. Conclusion: Both acid and non-acid reflux seem to play a significant role in the pathogenesis of GER-related BRUE in infants.