• Journal of Korea Water Resources Association
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• v.53 no.5
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• pp.383-393
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• 2020

The main objective of this study is to provide a robust model for estimating parameters of the Clark unit hydrograph (UH) using the observed rainfall-runoff data in the Soyangang dam basin. In general, HEC-1 and HEC-HMS models, developed by the Hydrologic Engineering Center, have been widely used to optimize the parameters in Korea. However, these models are heavily reliant on the objective function and sample size during the optimization process. Moreover, the optimization process is carried out on the basis of single rainfall-runoff data, and the process is repeated for other events. Their averaged values over different parameter sets are usually used for practical purposes, leading to difficulties in the accurate simulation of discharge. In this sense, this paper proposed a hierarchical Bayesian model for estimating parameters of the Clark UH model. The proposed model clearly showed better performance in terms of Bayesian inference criterion (BIC). Furthermore, the result of this study reveals that the proposed model can also be applied to different hydrologic fields such as dam design and design flood estimation, including parameter estimation for the probable maximum flood (PMF).

• Informatization Policy
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• v.27 no.4
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• pp.85-100
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• 2020

The purpose of this study is to investigate how level of digital information usage of the middle-aged or elderly people affects life satisfaction and whether social capital mediates the relationship between level of digital information usage and life satisfaction. In this study, we analyzed data of 1,661 people aged 55 or older from the 「2018 Survey on Digital divide」 by the National Information Society Agency. The SPSS 25.0 statistical package was used for the mutiple regression analysis and Baron and Kenny(1986)'s steps for mediation. The statistical significance of the mediated effects of social capital was verified by the Sobel Test. As a result of the analysis, the aged people have a higher life satisfaction when they are women and older, do not live alone, have higher levels of digital informatization usage and social capital. In addition, social capital also revealed to have a mediating role between level of digital information usage and life satisfaction. This shows that social capital needs to be considered along with the level of digital information usage as a way to improve life satisfaction of the middle-aged or the elderly people.

• Korean Journal of Culture and Social Issue
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• v.25 no.1
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• pp.55-77
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• 2019

Negative experience related to work-family multiple roles has been associated with internalizing problems in mothers. In particular, employed mothers with preschool children report high degree of stress. As such, the need to examine potential factors that may explain and alleviate such difficulties has been emphasized. The purpose of this study was thus to examine the mediating effect of sociotropy on the relationship between negative work-family multiple roles and internalizing problems in employed mothers with preschool children. The Negative Experience of Work-Family Multiple Roles Scale, Adult Self Report (ASR) Scale, and Personal Style Inventory-II (PSI-II), were completed by 208 employed mothers with preschool children through an online survey. The results indicated that the direct effect of negative experience of work-family multiple roles on internalizing problems was statistically significant and the indirect effect of sociotropy in this relationship was significant. These findings suggest that sociotropy in employed mothers may indirectly explain internalizing problems related to multiple roles. The implications of sociotropy in negative experience of work-family multiple roles and internalizing problems are discussed.

• Management & Information Systems Review
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• v.36 no.2
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• pp.261-276
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• 2017

One of the main objectives of this paper is to identify the mediating effects of both social and intellectual capitals in the relations between entrepreneurship and innovation performance in Small and Medium Businesses. Based on the previous literatures on their relationships, we set our research model and test our hypotheses through a questionnaire survey. The main results of our analyses are as followings: first, entrepreneurship has a significant effect on innovation performance; second, social capital has a significant mediating effect between entrepreneurship and innovation performance; and finally, there exists a significant mediating effect between intellectual capital and entrepreneurship. One of the main policy implications of this study would be that the level of both social and intellectual capitals, coupled with entrepreneurship, should be reinforced in order to improve innovation performance.

• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.100-101
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• 2007

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.468-472
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• 2000

This paper discusses the development of a acoustic vector channel simulator for the performance analysis of a acoustic digital communication system. The channel simulator consists of transmission module, acoustic channel model, receiver, beamformer, and adaptive equalizer. QPSK source signal is generated by the parameters specified by a user and transmitted. The transmitted signal generate multipath signals which have a different delay, amplitude, and dopper Sequency. The multipath signals with the acoustic noises is the received signal. We can analysis the communication system performance according to the antenna structure, beamforming algorithm, and equalization algorithm.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.4
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• pp.861-868
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• 2000

This paper discusses the development of an acoustic vector channel simulator for the performance analysis of an acoustic digital communication system. The channel simulator consists of transmission module, acoustic channel model, receiver, beamformer, and adaptive equalizer. QPSK source signal is generated by the parameters specified by a user. The transmitted signal generates multipath signals which have a different delay, amplitude, and dopper frequency. The multipath singnals with the acoustic noises are the received signal. This paper presents the performance analysis of an acoustic digital communication system according to the antenna structure and the various baseband signal processing techniques.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.01a
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• pp.189-190
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• 2023

본 연구에서는 노인의 생계급여와 기초연금 수급, 건강상태, 지역사회만족, 우울 간의 구조적 관계분석을 통해 노인의 우울 감소 방안을 제시하고자 한다. 분석자료는 2017년 노인실태조사 패널데이터 중 노인 본인이 직접 응답한 2,493명을 분석에 사용하였다. 분석결과, 첫째, 생계급여와 기초연금 수급은 노인의 건강상태에 정(+)적인 영향을 미쳤고, 지역사회만족에는 부(-)적인 영향을 미쳤고, 우울에는 정(+)적인 영향을 미쳤다. 둘째, 노인의 건강상태는 지역사회만족에 부(-)적인 영향을 미쳤고, 우울에 정(+)적인 영향을 미쳤다. 셋째, 노인의 지역사회만족은 우울에 부(-)적인 영향을 미쳤다. 넷째, 노인의 생계급여와 기초연금 수급과 우울사이에서 건강상태, 지역사회만족의 다중매개효과는 유의한 영향을 미치는 것으로 분석되었다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.6
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• pp.372-372
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• 2000

In this paper, we propose to use nonparametric detector for the PN code acquisition in DS/CDMA systems. Because the detector is nonparametric, we can decide the threshold of the detector without first haying to estimate the valiance of time-varying interference. We compare the proposed detector with the conventional detector by showing both analytic and simulation results. From these results, we can observe that the DS/CDMA system with the proposed detector have better performance than that with the conventional detector when the exact estimation of the interference variance is not possible.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2639-2641
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• 2003

유전자 알고리즘은 다윈의 자연선택설과 유전자의 진화 개념을 이용한 적응 탐색 알고리즘으로 적용하고자 하는 문제의 매개 변수를 유전자와 비슷한 데이터 구조로 부호화하고, 유전 연산자를 이용하여 문제의 해답을 찾는 알고리즘이다. 최근 유전자 알고리즘은 이러한 복수개의 목적 함수를 최적화 하기 위한 다중 최적화 문제를 위한 최적화 기술로서의 관심이 크게 다루어지고 있으며 전송 문제, 생산 공정 문제 계획 등과 같은 다목적 함수를 다루는 많은 응용 부분에 대해 적용되고 있다. 본 논문에서는 기본적인 다중 목적 함수용 예와 Gen과 Kim이 제안한 네트워크 신뢰도를 고려한 연결 비용과 메시지 지연을 고려한 이중 구속 통신망 설계 문제를 가지고 가중치 합과 여러 가지 파레토 방법들을 비교하고 연구 검토 하고자 한다.