• Journal of the Institute of Convergence Signal Processing
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• v.2 no.3
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• pp.39-44
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• 2001

In frequency hopping spread spectrum(FHSS) communication systems, exact frequency synchronization is required due to the random hopping of carrier frequencies between transmitter and receiver even under harsh channel conditions. For synchronization of FHSS communications, multi-frequency hopping synchronization(MFHS) method has been used in which a small set of frequencies are repeatedly sent several times for long duration. But this long duration resulted in being easily detected by the unauthorized users as well as long duration of acquisition time. In this paper, motivated by these problems, an adaptive synchronization method(ASM) is proposed. ASM is technics to reduce the synchronization time where the number of synchronization frequencies and repetition numbers is adaptively changed (increased or decreased) according to the channel conditions. The performance analysis showed that the time duration of synchronization was reduced to 0.2sec, and the influence of jamming or interference was decreased to 46% in ASM.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.106-108
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• 2004

연속적이고 동기화된 미디어 스트림을 요구하는 분산 가상 환경 (DVE: Distributed Virtual Environment) 시스템은 크게 3 개 계층, 즉 가상환경, 동기화, 그리고 네트워크 계층 등으로 나누어 질 수 있다. 그 중 동기화 계층의 목적은 그룹 멤버들 간에 일관된 전역적인 상태와 멤버쉽을 유지하게 하는 것이다. 분산 가상 환경에서 이질적인 종단 시스템들 간에 효율적인 미디어 재생을 위해 적응형 동기화 기업들이 연구 되어 왔으나 기존의 적응형 동기화 기업은 가변적인 재생지연의 조절로 인하여 skipping 과 pausing 현상 을 야기한다. 본 논문에서는 분산 가상환경 시스템에서 다자간 미디어 재생을 지원하기 위한 동기화 계층을 설계하고 구현하는 방법에 대해서 기술한다. 특히, 가변적인 네트워크 상태로 인해 발생되는 이벤트 패킷 지연 (delay) 과 순서 오류 (out of sequence) 를 수신 측에서 효과적으로 제어하기 위한 적응형 동기화 재생 기법을 제안하고 skipping 과 pausing 현상을 감소시키기 위한 재생 버퍼 구조를 소개한다. 실험을 통하여 제안된 기법의 효율성을 검증하였다.

• Journal of Korean Home Economics Education Association
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• v.20 no.4
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• pp.139-155
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• 2008

The purpose of this study was to investigate the relation among father's child-rearing involvement, father-child communication style, children's achievement motivation and school adjustment. The subjects were 236 - 5th and 6th graders of elementary schools in Daegu. The major findings were as follows: first, children's achievement motivation was affected by father's child-rearing involvement. Second, children's achievement motivation was affected by father-child communication style. Third, children's school adjustment was affected by father's child-rearing involvement. Fourth, children's school adjustment was affected by father-child communication style. Fifth, children's school adjustment was affected by achievement motivation. Sixth, father's open communication style was the most important variable to teacher adjustment compared to other variable. Children's achievement motivation was the most important variable to peer adjustment compared to other variable. Father's leisure activity involvement was the most important variable to school education adjustment compared to other variable. Children's achievement motivation was the most important variable to school rule adjustment compared to other variable.

• The Journal of the Convergence on Culture Technology
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• v.7 no.1
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• pp.518-524
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• 2021

The purpose of this study was to examine the correlation between academic achievement, major selection motivation, work value, and campus life adjustment of healthcare major college students. Data was collected using a structured questionnaire for 495 healthcare major college students at a four-year university located in G city. As a result of the study, Academic achievement was determined with positive correlation by major selection motivation (r=.446, p<.001), work values (r=.255, p<.001), campus life adjustment(r=.391, p<.001), Major selection motivation was positively correlated with work value (r=.354, p<.001) and campus life adjustment (r=.220, p<.001). The work value showed a positive correlation with the campus life adjustment(r=.193, p<.001). It is necessary to develop a career education program that reinforces college students' major selection motivation and their work values, and a student guidance program that improves their adaptation to college life.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.2
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• pp.270-275
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• 2005

This paper presents a fuzzy model-based adaptive approach for synchronization of chaotic systems which consist of the drive and response systems. Takagi-Sugeno (T-S) fuzzy model is employed to represent the chaotic drive and response systems. Since the parameters of the drive system are assumed unknown, we design the response system that estimates the parameters of the drive system by adaptive strategy. The adaptive law is derived to estimate the unknown parameters and its stability is guaranteed by Lyapunov stability theory. In addition, the controller in the response system contains two parts: one part that can stabilize the synchronization error dynamics and the other part that estimates the unknown parameters. Numerical examples, including Doffing oscillator and Lorenz attractor, are given to demonstrate the validity of the proposed adaptive synchronization approach.

• Proceedings of the Korea Contents Association Conference
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• 2015.05a
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• pp.165-166
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• 2015

본 연구의 목적은 보건계열 대학생들의 소명의식, 일의 의미, 진로태도성숙도 및 대학생활적응과의 관계를 탐색하고자 하였다. D대학 보건계열 학생 261명을 대상으로 2014년 10월 4일부터 일주일간 편의추출하였다. 대상자들의 일반적 특성에 따라 소명의식은 전공, 지난 학기 성적, 학과지원동기, 아르바이트 형태에서 차이가 있었으며 일의 의미는 전공, 학과지원동기, 진로태도성숙도는 전공, 학과지원동기, 대학생활적응은 성별, 전공, 학년, 지난학기 성적, 학과지원동기, 가정형편, 아르바이트 형태에 따라 통계적으로 유의한 차이를 나타내었다. 주요 변수들과의 상관관계에서는 소명의식과 일의 의미, 대학생활적응, 일의 의미와 진로태도성숙도와 대학생활적응이 양의 상관관계를 나타낸 반면, 진로태도성숙도와 대학생활적응은 음의 상관관계를 나타내었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8C
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• pp.697-708
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• 2010

In this paper, we compare the timing synchronization performance of the adaptive filter to that of the correlator in direct sequence spread spectrum (DS/SS) systems. The test variables used in the code synchronization are statistically analyzed for both schemes, and then the obtained results are used in calculating the detection and false alarm probabilities. Based on the derived probabilities, the synchronization performance is compared and the simulation is followed. Analysis and simulation results show that the correlator outperforms the adaptive filter under most synchronization environments.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.225-234
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• 2018

The purpose of this study was to examine relationships among drinking motives, acculturative stress and problem drinking, and then to identify the influencing factors of problem drinking in foreign workers. A total of 120 foreign workers recruited from two shipyards in G city. Self-reported questionnaire survey was conducted from October to December, 2016. As a result, a rate of problem drinking in foreign workers was 39.2%. According to the multiple regression analysis, their problem drinking was significantly influenced by social motives (${\beta}=.368$ p=.003) and conformity motives (${\beta}=.337$ p=.005) as a subscale of drinking motives and homesickness (${\beta}=-.197$, p=.009) as a subscale of acculturative stress, explained 39.5% of the total variance (F=26.849, p=.000). Based on our results, an education program using drinking motives, acculturative stress should be developed to prevent problem drinking in foreign workers.

• Proceedings of the KIEE Conference
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• 2007.10c
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• pp.141-143
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• 2007

본 논문은 매입형 영구자석 동기전동기의 속도 센서리스의 제어 방법에 관한 것이다. 매입형 영구자석 동기전동기의 센서리스 구동을 위하여 적응 적분바이너리 관측기와 적응 슬라이딩 모드 관측기를 이용하였다. 두 관측기의 성능 비교를 위하여 매입형 영구자석 동기전동기의 고정자 전압방정식으로부터 각각 관측기를 구성하였고, 동일한 시스템에서의 실험을 통하여 관측기의 성능을 비교하였다.

• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.657-666
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• 2021

This study was conducted to understand the motivation for major selection and degree of satisfaction with major for university students in the department of Radiology, and to analyze the effect university life adjustment in COVID-19. From Jung 20 to July 20, 2021, 308 students in grades 1~4 were enrolled at universities in Busan and Gyeongnam. Factors influencing university life adjustment were found to have a good adjustment when majoring was selected with personal motive rather than social motive. Among the sub-factors of major satisfaction, general satisfaction and satisfaction with surrounding relationships had a positive effect on university life adjustment. Therefore, in order to adapt to healthy university life, it is necessary to secure closeness between school, professor, and students, and it is desirable to provide students with opportunities to experience various education by recognizing the rapidly changing policy changes in education to increase major satisfaction. Based on the results of this study, it is expected that the results of this study will be used as basic data for successful university life of students in the department of radiology.