• Journal of Korea Water Resources Association
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• v.53 no.9
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• pp.647-660
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• 2020

The objectives of this study are to develop a framework for selecting multi-GCMs considering Asia monsoon characteristics and assess it's applicability. 12 climate variables related to monsoon climates are selected for GCM selection. The framework for selecting multi-GCMs includes the evaluation matrix of GCM performance based on their capability to simulate historical climate features. The climatological patterns of 12 variables derived from individual GCM over the summer monsoon season during the past period (1976-2005) and they are compared against observations to evaluate GCM performance. For objective evaluation, a rigorous scoring rule is implemented by comparing the GCM performance based on the results of statistics between historical simulation derived from individual GCM and observations. Finally, appropriate 5 GCMs (NorESM1-M, bcc-csm1-m, CNRM-CM5, CMCC-CMS, and CanESM2) are selected in consideration of the ranking of GCM and precipitation performance of each GCM. The selected 5 GCMs are compared with the historical observations in terms of monsoon season and monthly mean to validate their applicability. The 5 GCMs well capture the observational climate characteristics of Asia for the 12 climate variables also they reduce the bias between the entire GCM simulations and the observational data. This study demonstrates that it is necessary to consider various climate variables for GCM selection and, the method introduced in this study can be used to select more reliable climate change scenarios for climate change assessment in the Asia region.

• Journal of Korea Water Resources Association
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• v.52 no.6
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• pp.381-395
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• 2019

The purpose of this study is to predict agricultural reservoir storage rate (RSR) in a month. This algorithm was developed by multiple linear regression model (MLRM) which included the past 3 months RSRs data and the future climate change scenarios. In order to improve use of predicted RSR, this study need the severe criteria in terms of drought. So, the predicted RSR was indexed as the 3 months reservoir drought index (RDI3) and then it was disaggregated into drought duration, severity, and intensity. For the future RSR estimation by climate change scenarios, the 6 RCP 8.5 scenarios of HadGEM2-ES, CESM1-BGC, MPI-ESM-MR, INM-CM4, FGOALS-s2, and HadGEM3-RA were used in three future evaluation periods (S1: 2011~2040, S2: 2041~2070, S3: 2071~2099). The future S3 period of HadGEM2-ES scenario which has the biggest increase in precipitation and temperature showed the largest decrease to 60.2% among the 6 scenarios compared to the historical RSR (1976~2005) 77.3%. In contrast, INM-CM4 scenario which has smallest changes in precipitation and temperature in S3 period showed the smallest decrease to 72.8%. For the CESM1-BGC and MPI-ESM-MR, FGOALS-s2, and HadGEM3-RA, the S3 period RSR showed 72.6%, 72.6%, 67.4%, and 64.5% decrease respectively. The future severe drought condition of RDI3 below -0.25 showed the increase trend for the number and severity up to -2.0 during S3 period.

• Proceedings of KHEA Conference
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• 2004.04a
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• pp.190-190
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• 2004

• Journal of the Korean Home Economics Association
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• v.43 no.2
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• pp.203-229
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• 2005

The purpose of this study was to explore the perceived quality of life of Korean university students'. The perceived quality of life was composed of three dimensions: emotion, cognitive efficiency, and satisfaction. The study results were as follow: 1. Korean university students felt more positive emotions when they spent time for social activities. 2. In the cognitive efficiency, social activities also scored highly of 5 questions, but in the item of "awareness of another person's eye", productive activities were higher. 3. Korean university students were more satisfied with themselves when they spent time for productive activities. However, they were more satisfied with their work itself when the work was social activities. 4. Korean university students' emotions, cognitive efficiencies, and satisfaction were significantly different by socio-graphic variables and context.

• The Journal of the Acoustical Society of Korea
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• v.23 no.1
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• pp.40-46
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• 2004

The equivalent source method (ESM) uses two groups of equivalent source positions. One group includes the first order images of the sound source inside the enclosure. The positions of the other group are usually on a spherical surface some distance outside the enclosure. A proper selection of the positions for the far field sources could greatly improve the performance of the modeling accuracy and reduce the number of the sources to achieve the required accuracy. This study uses optimally distributed far field source positions on the surface of enlarged version of the rectangular enclosure instead of using typical spherical distribution. Simulations using various sizes of the box shaped distribution are executed and optimal positions are searched using an optimization technique from the larger number of candidate positions. The results of using these far field source positions are compared and analyzed.

• Korean Journal of Child Studies
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• v.33 no.4
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• pp.19-34
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• 2012

This study investigated the differences in time use patterns and psychological states across daily activity contexts and interpersonal contexts, depending on the levels of school maladjustment among elementary school students. Using the Experience Sampling Method (ESM), 107 elementary school 6th grade students' daily time use patterns and psychological states across daily contexts were measured six times a day over a period of 4 days. Using the school maladjustment scale, an internal problem based school maladjusted group and an external problem based school maladjusted group were identified and selected. The daily time use patterns and psychological states of both school maladjusted groups were compared to those of the adjusted groups. The principle findings are as follows: first, the school maladjusted group students' daily time use patterns across daily activity contexts or interpersonal contexts did not differ from those of the students from the school adjusted group. Second, the school maladjusted group students experienced more negative emotions, lower concentration levels, and lower motivation levels across daily contexts than the school adjusted group students. These differences in motivation between the external problem school maladjusted group and adjusted group, however, were greater in the schoolwork context compared to the other daily activity contexts. The findings were discussed in the contexts of the daily experiences of child school maladjustment.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.9
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• pp.1039-1048
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• 2015

In this paper, we propose an efficient stair locomotion method for a quadruped robot with mechanism of insectile legs using genetic algorithm(GA). In the proposed method, we first define the factors and the reachable region for the stair locomotion. In addition, we set the gene and the fitness function for GA and generate the gait trajectory by searching the landing position of a quadruped robot, which has the minimun distance of movement and the optimal energy stability margin(ESM). Finally, we verify the effectiveness and superiority of the proposed stair locomotion method through the computer simulations.

• Korean Journal of Human Ecology
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• v.16 no.2
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• pp.349-365
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• 2007

The purpose of this study was to explore the Korean housewives' consumption experiences and perceived quality of life. Perceived quality of life was composed of four dimensions: motivation, affect, efficiency, and activation. The study results are: 1. Housewives spare their time for physiologic activities(22.9%), household activities(20.1), and personal activities(10.1%) in sequence. 2. Although the motivation that housewives do shopping activities is coming from a sense of duty, the perceived quality of life during shopping is showing far more positive affect than the perceived quality of life during other activities. In this context, shopping activities are interesting in that they are thought of a kind of entertainment as well as work. 3. With an analysis of covariance, housewives' perceived quality of life has an effect on everyday life in that 4 perceived qualities of life such as motivation, affect, efficiency and activation has a significant effect on flow and it has a significant effect on satisfaction.

• Convergence Security Journal
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• v.11 no.6
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• pp.3-8
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• 2011

Advanced Persistent Threat (APT), aims a specific business or political targets, is rapidly growing due to fast technological advancement in hacking, malicious code, and social engineering techniques. One of the most important characteristics of APT is persistence. Attackers constantly collect information by remaining inside of the targets. Enterprise Security Management (EMS) system can misidentify APT as normal pattern of an access or an entry of a normal user as an attack. In order to analyze this misidentification, a new system development and a research are required. This study suggests the way of forecasting APT and the effective countermeasures against APT attacks by categorizing misidentified data in data-mining through threshold ratings. This proposed technique can improve the detection of future APT attacks by categorizing the data of long-term attack attempts.

• The KIPS Transactions:PartC
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• v.10C no.1
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• pp.1-10
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• 2003

In this paper, we propose a secure communication framework for interaction and information sharing between a server and agents in DS-NVSA(Detection System of Network Vulnerability Scan Attacks) proposed in〔1〕. For the scalability and interoperability with other detection systems, we design the proposed IDMEF and IAP that have been drafted by IDWG. We adapt IDMEF and IAP to the proposed framework and provide SKTLS(Symmetric Key based Transport Layer Security Protocol) for the network environment that cannot afford to support public-key infrastructure. Our framework provides the reusability of heterogeneous intrusion detection systems and enables the scope of intrusion detection to be extended. Also it can be used as a framework for ESM(Enterprise Security Management) system.