• The Journal of Information Systems
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• v.22 no.1
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• pp.65-87
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• 2013

The development and expansion of communication technology in the field of information technology (IT) have changed the method and culture of communication, mediating communication among people. In particular, since social network service (SNS) has the attributes of information delivery and processing, it has a more powerful dissipating effect and influence than other existing communication methods. The role of users in SNS is important because it has the communication structure of producer-consumer, which consists of sharing, connection and participation of users. In this line, the purpose of this study is to investigate the intention for continued use of SNS by user ability. In order to explain the motivation and behavior for continued use of SNS by users, this study employed the motivation theory and post-adaptation model. The study applied 'media literacy' to the characteristics of SNS media and environment and expanded it into the concept of 'SNS literacy' to identify the moderating effect by user ability. Referred to as 'user's ability that is required to use SNS,' the SNS literacy was verified for its moderating effect with the three sub-dimensions: 'technical accessing ability,' 'understanding ability' and 'creative ability.' The major findings of this study are as follows. First, the perceived usefulness and playfulness were found to have a significant effect on the intention for continued use of SNS, showing the same result with previous studies on technology acceptance. In other words, usefulness and playfulness are variables with an explanatory power in the SNS environment as well. Second, the conceptualization of SNS literacy with accessing ability, understanding ability and creative ability was found to be valid. Third, it was verified that there was a significant difference in the SNS literacy between perceived usefulness and continued use, indicating that users with higher ability respond sensitively to usefulness and affect continued behavior. The moderating effect of SNS literacy was also verified in the relationship between perceived playfulness and intention for continued use. The results above confirm the difference in post-adaptation behavior of individuals, and are expected to provide several implications.

• Journal of Digital Convergence
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• v.16 no.5
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• pp.373-383
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• 2018

The purpose of this study was to identify menopausal resilience in middle-aged women. The data were collected from 227 middle-aged women who participated in friendship and religious activities in the Jeonbuk province. The data were collected through self-report questionnaires, which were constructed to Self-efficacy, family support, social support, menopausal adaptation, resilience. Data were analyzed using frequencies, means, $X^2$_Test, pearson's correlation coefficient and multiple regression with SPSS/WIN 23. Regular exercise(${\beta}=-.15$, p<.01), self-efficacy(${\beta}=.29$, p=<.001), social support(${\beta}=.29$, p=<.001), menopausal Adaptation(${\beta}=.17$, p<.01) were influencing factors and these variables showed an explanatory power of 35.3% (F=18.65, p<.001). Therefore, it is suggested that middle-aged women in menopause can plan to overcome the menopausal crisis positively through nursing interventions that include self-efficacy and social support.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2015.07a
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• pp.78-80
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• 2015

광적응(Luminance Adaptation; LA) 효과는 영상의 배경 밝기에 따른 왜곡에 대한 시각 인지 민감도가 달라지는 특성을 의미한다. 기존 영상 화질 측정(Image Quality Assessment; IQA) 방법들은 베버의 법칙(Weber' s law) 모델을 이용하여 LA 효과를 IQA 방법에 반영해왔다. 그러나, 이러한 IQA 방법들에 있어서 베버의 법칙 기반 LA 효과 모델은 다음 두 가지 이유로 부정확하게 동작한다: (i) 전통적인 베버의 법칙 모델은 실제 광도(luminance)에 대한 인지 민감도 응답값을 정확히 반영할 수 없다는 것이 밝혀졌다, (ii) 대부분 IQA 방법들은 픽셀 강도 영역에서 계산되지만, 베버의 법칙과 같은 LA 효과 모델들은 광도 영역에서 개발되었다. 따라서 광도와 픽셀 강도간 비선형 관계로 인해 IQA 방법에 반영된 베버의 법칙 기반 LA 효과 모델들은 부정확하게 동작한다. 이 문제를 해결하기 위해, 본 논문에서 처음으로 픽셀 강도 영역에서의 LA 모델을 이론적으로 유도한다. 본 논문에서 제안하는 픽셀 강도 영역에서의 LA 효과 모델은 감마 교정 함수(Gamma correction function)와 광도 영역에서의 LA 효과 모델인 제곱-법칙(power-law) 모델을 기반으로 하는 테일러 급수 확장 근사화를 통해 유도된다. 제안하는 픽셀 강도 영역 LA 효과 모델의 효과를 검증하기 위해, 제안하는 LA 효과 모델을 PSNR 에 도입하여 광범위한 실험을 수행한다. 실험 결과, 제안하는 LA 효과 모델 기반 PSNR 은 PSNR 및 베버의 법칙 기반 PSNR 대비 괄목할 만한 주관적 화질 예측 성능 향상을 보였다.

• Journal of Family Resource Management and Policy Review
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• v.17 no.4
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• pp.189-213
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• 2013

The purpose of this work is to explore different types of intergenerational relationships in the later lives of old retirees. This will be done according to the eligibility of public pension and the old age social security system so that the factors affecting intergenerational relationships can be analyzed, and to propose a plan to improve social adaptation in later life. The data used in this work are the Fourth basic survey data of the 2011 Korea Retirement and Income Study. The study subjects of this work were 2,435 retirees over age 65 who had children. In this study, latent class analysis and logistic regression analysis were conducted to classify types of intergenerational relationships and to analyze the influence of relevant factors. As a result of the analysis, some of those in the group were eligible for public pension, and the ones who were not were classified into three types: the closely-living-together type, the separate-living-contact type, and the estrangement type. In the group not eligible for public pension, it was found that age, spouse, number of children, economic factors, and level of health satisfaction gave significant power to intergenerational relationships. In the group eligible for public pension, it was found that age, income and net assets, ADL(Activities of Daily Living), whether there was an IADL(Instrumental Activities of Daily Living) spouse, and number of children affected types of intergenerational relationships; Socio-demographic factors, economic factors, and healthy factors became significant variables according to the classified types of intergenerational relationship. Based on the study results, this work suggested such necessities to lay the foundation for an elderly welfare system for social adaptation in later life, This includes the offering of programs for retirement preparation, the use of family and local society resources, and expansion of the opportunity to participate in social activities.

• Journal of Internet Computing and Services
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• v.14 no.4
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• pp.85-90
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• 2013

Currently, the electric fire prediction system uses PIC(Peripheral Interface Controller) for controller microprocessor. PIC has a slower computing speed than DSP does, so its real-time computing ability is inadequate. So with the basic characteristics waveform during arc generation as the standard reference, the comparison to this reference is used to predict and alarm electric fire from arc. While such alarm can be detected and taken care of from a remote central server, that prediction error rate is high and remote control in mobile environment is not available. In this article, the arc detection of time domain and frequency domain and wavelet-based adaptation algorithm executing the adaptation algorithm in conversion domain were applied to develop an electric fire prediction system loaded with new real-time arc detection algorithm using DSP. Also, remote control was made available through iPhone environment-based app development which enabled remote monitoring for arc's electric signal and power quality, and its utility was verified.

• Journal of IKEEE
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• v.22 no.3
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• pp.651-657
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• 2018

IEEE 802.11 wireless LANs support 20, 40, 80 and 160MHz bandwidth transmission. In general, the data rate increases as the transmission bandwidth increases. However, the transmission power spectral density decreases, which may lead to increasing packet errors and retransmissions. In this paper, we derive a mathematical model of energy consumption with consideration of various factors such as transmission bandwidth, packet error rate and data size. Based on the model, we design a scheme to adapt a transmission bandwidth for each frame transmission. The scheme estimates packet error rates for different bandwidth cases, updates the table of energy consumption and selects the best bandwidth for the next transmission. The simulation study with VoIP traffic shows the energy consumption of the scheme under various environments.

• Nuclear Engineering and Technology
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• v.25 no.1
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• pp.110-124
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• 1993

A Nonlinear model-based Hybrid Controller (NHC) is developed which consists of the adaptive proportional-integral-feedforward (PIF) gains and variable structure controller. The controller has the robustness against modeling uncertainty and is applied to the trajectory tracking control of single-input, single-output nonlinear systems. The essence of the scheme is to divide the control into four different terms. Namely, the adaptive P-I-F gains and variable structure controller are used to accomplish the specific control actions by each terms. The robustness of the controller is guaranteed by the feedback of estimated uncertainty and the performance specification given by the adaptation of PIF gains using the second method of Lyapunov. The variable structure controller is incorporated to regulate the initial peak of the tracking error during the parameter adaptation is not settled yet. The newly developed NHC method is applied to the power tracking control of a nuclear reactor and the simulation results show great improvement in tracking performance compared with the conventional model-based control methods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.11a
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• pp.363-367
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• 1999

As the subscription rate to both Internet services and wireless communications services increases rapidly, traffic in the future wireless communications will be dominated by Internet applications. Current research for wireless technology is focused to the multimedia data transmission mainly for the personal computer or notebook whose display which has large display and abundant memory. But in the near future, Internet access request from the handphone or PDA device which is already spreaded in the world will be large. Special handset terminals which has small display monitor, low capacity memory and poor processing power has to be managed differently from torrent wireless communications protocols. So, WAP Forum is organized with wireless handset manufacturers in the world and the standardization process for wireless application is being actively developed. In this paper, basic model and architecture of WAP is introduced and adaptation requirements for change from HTML documents to WML formats are proposed. Also, compression ratio gained in the transform from the existing web documents to WML is shown.

• ETRI Journal
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• v.42 no.4
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• pp.585-595
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• 2020

Integration of multiple communication technologies in a smart grid (SG) enables employing cognitive radio (CR) technology for improving reliability and security with low latency by adaptively and effectively allocating spectral resources. The versatile features of the CR enable the smart meter to select either the unlicensed or the licensed band for transmitting data to the utility company, thus reducing communication outage. Demand response management is regarded as the control unit of the SG that balances the load by regulating the real-time price that benefits both the utility company and consumers. In this study, joint allocation of the transmission power to the smart meter and consumer's demand is formulated as a two stage multi-armed bandit game in which the players select their optimal strategies noncooperatively without having any prior information about the media. Furthermore, based on historical rewards of the player, a real-time pricing adaptation method is proposed. The latter is validated through numerical results.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2090-2092
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• 2003

Adaptive algorithms are widely used for various applications. One challenging application is an echo canceller in the long distance telephony network. This paper proposes the new variable step-size algorithm for adaptive lattice structure for echo cancellation. The new algorithm is using power of the output signal and the error signal to controlled the step of adaptation process. By this technique, the proposed algorithm is an excellent and effective in good stability. Performance comparison of the proposed algorithm and the other algorithm is made through simulation results.