• 한국통신학회논문지
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• 제28권3C호
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• pp.264-270
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• 2003

Application of the Filtered-X LMS adaptive filter to active noise control requires to estimate the transfer characteristics between the output and the error signal of the adaptive canceler. In this paper, we derive an adaptive control algorithm and analyze its convergence behavior when the acoustic noise is assumed to consist of multiple sinusoids. The results of the convergence analysis of the Filtered-X LMS algorithm indicate that the effects of parameter estimation inaccuracy on the convergence behavior of the algorithm are characterize by two distinct components : Phase estimation error and estimated magnitude. In particular, the convergence of the Filtered-X LMS algorithm is shown to be strongly affected by the accuracy of the phase response estimate. Simulation results of the algorithm are presented which support the theoretical convergence analysis.

• Structural Engineering and Mechanics
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• 제91권5호
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• pp.517-526
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• 2024

Due to the asymmetric cross-section of unequal-angle steel, the application of loads can induce axial rotation, leading to a series of buckling failure behaviors. Special attention must be paid during the design process. The present study aims to analyze the structural behavior of asymmetric steel angle members under various eccentric loading conditions, considering the complex biaxial bending interaction that arises when the angle steel is connected to the panel. Several key factors are investigated in this paper, including the effects of uniaxial and biaxial eccentricity on the structural behavior and the eccentric axial compression strength of long and short legs at different load application points. Potential risks associated with the specified load points, based on the AISC specifications, are also discussed. The study observed that the strength values of the members exhibited significant changes when the eccentric load deviates from the specified point. The relative position of the eccentric load point and the slenderness ratio of the member are critical influencing factors. Overall, this research intends to enhance the accuracy and reliability of strength analysis methods for asymmetric single angle steel members, providing valuable insights and guidance for a safer and more efficient design.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제3권1호
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• pp.47-53
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• 2022

The escape behavior of prey fish to predator attack is directly linked to the survival of the fish. In this study, I explored the escape behavior of Medaka fish to bird attacks. To simulate the attack, I designed a model triangular-shaped bird to slide along a fishing line connected between rods at both ends of the tank. The triangular shape was set to 10×15 (S=1), 15×20 (S=2), and 20×25 cm (S=3) with base×height. The slope (θ) of the fishing line, which determines the attack speed of the model bird, was set to values of 15° (θ=1), 30° (θ=2), and 45° (θ=3). The escape behavior was characterized using five variables: escape speed (ν), escape acceleration (α), responsiveness (γ), branch length similarity entropy (ε), and alignment (ϕ). The experimental results showed when (S, θ)=(fixed, varied), the change in values of the five variables were not significant. Thus, the fish respond more sensitively to S than to θ In contrast, when (S, θ)=(varied, fixed), ν, α, and γ showed increasing trends but ε and ϕ did not change much. This indicates the nature of fish escape behavior irrespective of the threat is inherent in ε and ϕ. I found that fish escape behavior can be divided into two types for the five physical quantities. In particular, the analysis showed that the type was mainly determined by the size of the model bird.

• 감성과학
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• 제19권4호
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• pp.13-20
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• 2016

최근 사용자들의 일상생활을 실시간으로 측정하고 기록하며 타인과의 공유까지 확장되고 있는 라이프로깅 서비스가 증가하고 있다. 특히, 웨어러블 디바이스와 스마트폰의 발달로 애플리케이션에 기반한 라이프로깅 서비스가 대중화되면서 사용자 행태에 의해 서비스 콘텐츠가 제작되고 메뉴화되어 인포그래픽 형태로 제공되고 있다. 따라서 본 논문에서는 라이프로깅 서비스의 콘텐츠 항목을 구성하기 위한 사용자 행태를 추출하고 분류하는데 목적이 있다. 본 연구를 위하여 첫째, 학술 서적과 논문, 단행본을 포함한 도서, 출판물 등 문헌조사를 통한 라이프로깅의 개념과 특징을 살펴보고 기존의 라이프로깅 관련 사용자 행태 기반 콘텐츠 항목을 살펴본다. 둘째, 라이프로깅 서비스를 위한 콘텐츠 항목으로서 사용자 행태를 추출하고 분류 한다. 문헌 자료, 선행 논문 및 라이프로깅 애플리케이션의 콘텐츠 항목에서 사용자 행동 어휘를 수집한다. 수집된 어휘는 FGI(Focus Group Interview)와 설문을 통한 적합성 검정 분석에 의하여 라이프로깅 서비스를 위한 콘텐츠 항목에 필요한 39개 어휘를 추출한다. 최종적으로 추출한 39개 어휘는 설문과 통계 분석 및 FGI를 통해 19개 사용자 행태 - '먹다', '집안일을 하다', '다이어트를 하다', '여행하다', '운동하다', '대중교통 수단을 이용하다', '촬영하다', '만나다', '감정을 느끼다', '말하다', '보살피다', '운전하다', '듣다', '온라인에 접속하다', '잠자다', '가다', '일하다', '배우다', '보다'-로 분류되었다. 셋째, 본 연구를 통해 제시한 결과를 통하여 라이프로깅 애플리케이션에서의 콘텐츠 항목 구성에 대한 활용과 한계점을 논할 것이다.

• 한국세라믹학회지
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• 제46권6호
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• pp.643-647
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• 2009

We investigated the viscosity behavior and the carbon yield of coal tar pitch (CTP) treated with iodine. The viscosity of iodine treated pitch showed that the fluidity of iodine treated CTP did not increase within the iodine addition of 1.4%. DTG analysis showed that cross linking was accelerated at the temperature range from $400\;to\;500{^{\circ}C}$ with iodine treatment, which is due to the accelerated dehydrogenative reaction by iodine. The iodine treatment was mainly effective for β-resin content increase of CTP. The carbon yield of CTP increased from 40 to 60% by the iodine non-treated CTP.

• IEIE Transactions on Smart Processing and Computing
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• 제5권2호
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• pp.94-99
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• 2016

Application layer attacks have for years posed an ever-serious threat to network security, since they always come after a technically legitimate connection has been established. In recent years, cyber criminals have turned to fully exploiting the web as a medium of communication to launch a variety of forbidden or illicit activities by spreading malicious automated software (auto-ware) such as adware, spyware, or bots. When this malicious auto-ware infects a network, it will act like a robot, mimic normal behavior of web access, and bypass the network firewall or intrusion detection system. Besides that, in a private and large network, with huge Hypertext Transfer Protocol (HTTP) traffic generated each day, communication behavior identification and classification of auto-ware is a challenge. In this paper, based on a previous study, analysis of auto-ware communication behavior, and with the addition of new features, a method for classification of HTTP auto-ware communication is proposed. For that, a Not Only Structured Query Language (NoSQL) database is applied to handle large volumes of unstructured HTTP requests captured every day. The method is tested with real HTTP traffic data collected through a proxy server of a private network, providing good results in the classification and detection of suspicious auto-ware web access.

• 보건교육건강증진학회지
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• 제32권5호
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• pp.17-31
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• 2015

Objectives: This paper aims to identify the health related behaviors patterns and its associated factors among marriage immigrant women in Korea, and discusses their application to health promotion strategies. Methods: The study participants were 7,591 immigrant wives in Gyeonggi province who participated in health examinations conducted by the Korea Association of Health Promotion in 2011-2013. The participants completed self-administered questionnaires on sociodemographics, psychological characteristics, health status and health care factors, and health related behaviors. Results: A 3-latent-class model of health behaviors was identified related to 'lack of physical activity', 'abnormal diet', and 'not experienced medical check-up': 'high risk class', 'middle risk class', and 'low risk class'. Most of the participants belong to 'middle risk class'. Country of origin, age, length of stay, number of children, work status, health insurance status, and unmet health care needs were associated with problematic health behaviors in middle risk health behavior class. Conclusions: Health promotion and intervention programs for marriage immigrant women and their family members need to consider the health behavior patterns of physical inactivity, abnormal diet and no medical check-up and develop multiple behavior intervention with pre-existing program modification.

• 가정과삶의질연구
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• 제27권1호
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• pp.165-179
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• 2009

The purpose of this study is to analyze the effectiveness of a host family experience program on the adaptive behavior and self-management skills of children with severe disabilities and to suggest its applicability into clinical practice. The investigators developed a host family experience program and researched the pre-test and post-test designs with nonequivalent groups. The experiment and comparison groups were comprised of 34 children with severe disabilities that lived at S, a care facility for the severely disabled. They were examined for the program's effects on them before and after the application. After analyzing 17 cases for differences in the subjects' quantitative scores, a qualitative analysis was carried out on one representative case. The quantitative analysis results reveal that the experiment group showed a significant increase in their scores of adaptive behavior and self-management skills compared to the comparison group. Positive changes were also observed among the former group in the qualitative analysis. Thus the host family experience program was effective in improving the adaptive behavior and self-management skills of the children with severe disabilities at the facility. These findings indicate that the host family experience program played a positive role in enhancing the adaptive behavior and self-management skills of the children with severe disabilities at the facility and that such host family experience programs should be applied and reinforced in the field of social welfare practice.

• 디지털융복합연구
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• 제20권5호
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• pp.559-567
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• 2022

본 연구에서는 스마트폰 이용동기가 어플리케이션 디스플레이 광고태도와 광고회피에 미치는 영향을 확인하였다. 또한, 광고침입성의 매개효과를 확인하였다. 연구참여자는 309명이며 설문조사방법을 이용하여 자료를 수집하였다. 공변량구조분석을 이용하여 스마트폰 이용동기와 어플리케이션 디스플레이 광고태도간의 인과관계를 분석하였으며, 광고침입성의 매개효과를 검증하였다. 연구결과, 첫째 스마트폰 이용동기는 스마트폰 어플리케이션 디스플레이 광고태도에 유의미한 영향을 미쳤다. 둘째, 스마트폰 어플리케이션 디스플레이 광고태도가 광고회피행동에 유의미한 영향을 미쳤다. 셋째, 스마트폰 어플리케이션 디스플레이 광고태도는 지각된 광고침입성에 유의미한 영향을 미쳤다. 넷째, 스마트폰 에플리케이션 디스플레이 광고의 침입성 지각은 광고회피행동에 유의미한 영향을 미쳤다. 마지막으로, 스마트폰 어플리케이션 디스플레이 광고태도와 광고회피 행동간에 인과관계에서 광고침입성 지각은 매개효과를 미쳤다. 본 연구결과는 광고회피 행동을 감소시키는 전략을 제안하는데 기여할 것이다.

• Journal of Welding and Joining
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• 제16권6호
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• pp.104-112
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• 1998

In the previous study, the countermeasure for welding deformation of bracket tilt is through up through experimental inspection for total process including welding process. For completeness of systematic examination of parts having sensitivity on welding deformation, the comparison and feedback between the result through simulation of welding process and experimental data is needed. In other words, it is necessary to control welding deformation that construct the prediction system for welding deformation through comparison and tuning with experimental data. In the present study, the application of FEA on welding process of bracket tilt with susceptibility to deformation is made and deformation behavior through change of welding sequence is focused on. It is used to improve the exactness of deformation analysis that three dimensional analysis for moving heat source, activated and deactivated bead element, and volume heat flux etc.