• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.42-48
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• 2013

The present study assessed the amount of $CO_2$ uptake owing to concrete carbonation through a case study for an apartment building with a principal wall system and an office building with Rahmen system under different exposed environments during use phase and recycling application. The $CO_2$ uptake assessment owing to concrete carbonation followed the procedure established by Yang et al. As input data necessary for the case study, actual surveys conducted in 2012 in Korea, which included data about the climate environments, $CO_2$ concentration, lifecycle inventory database, life expectancy of structures, and recycling activity scenario, were used. From the comparisons with the $CO_2$ emissions from concrete production, the $CO_2$ uptake during the lifetime of structures was estimated to be 5.5~5.7% and that during recycling activity after demolition was 10~12%; as a result, the amount of $CO_2$ uptake owing to concrete carbonation can be estimated to be 15.5~17% of the $CO_2$ emissions from concrete production, which roughly corresponds to 18-21% of the $CO_2$emissions from cement production as well.

• Science of Emotion and Sensibility
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• v.21 no.1
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• pp.71-82
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• 2018

Stress involves changes in behavior, autonomic function and the secretion of hormones. Autonomic nervous system (ANS) contributes to physiological adaptive process in short durations. In particular, heart rate variability (HRV) analysis is commonly used as a quantitative marker depicting the ANS activity related to mental stress. The aim of this study is to investigate correlations between psychological responses to stress and HRV indices induced by the cognitive stressor. Thirty-three participants rated their mental and physical symptoms occurred during the past two weeks on Stress Response Inventory (SRI), which is composed of seven stress factors that may influence the status of mental stress levels. Then, they underwent the psychophysiological procedures, which are collected electrocardiogram (ECG) signals during a cognitive stress task. HRV indices, the standard deviation of R-R interval (SDNN), root mean square of successive R-R interval difference (RMSSD) and low frequency (LF)/high frequency (HF) ratio were extracted from ECG signals. Physiological responses were calculated stress responses by subtracting mean of the baseline from the mean of recovery. Stress factors such as tension, aggression, depression, fatigue, and frustration were positively correlated to HRV indices. In particular, aggression had significant positive correlations to SDNN, RMSSD and LF/HF ratio. Increased aggressive responses to stress correlated with the increases of all HRV indices. This means the increased autonomic coactivation. Additionally, tension, depression, fatigue, and frustration were positively associated with RMSSD reflecting increases in parasympathetic activation. The autonomic coactivation may represent an integrated response to specific cognitive reactions such as the orienting response.

• Journal of the Korea Society for Simulation
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• v.24 no.4
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• pp.163-170
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• 2015

This research is to focus on the method of moving line optimization in Agricultural Industry, especially Garak Wholesale Market Modernization Project, by using simulation tool. As everybody knew, it's very difficult to apply the SCM operation rules in Agricultural Industry, because the standardization system in Agricultural Industry was not completed. The five flow management factors, vehicle moving line management, customer moving line Management, Logistics Device Moving Line Management, Working Person Moving Line Management, Product display moving line management, are needed to be optimized on the basis of standardization rules, and to achieve this will be the good infrastructure to make the Agricultural SCM system. It's very different between the SCM structure of manufacturing industry and logistics industry and the SCM structure of Agricultural Industry, because the SCM in manufacturing is occur in the basis of flow management, on the contrary, the SCM of Agricultural Industry is on the basis of activity management. For these reason, this study is the first approach to apply the simulation method in the part of moving line optimization in Agricultural SCM, and in near future, This study will help all designers and operators to apply the simulation work in the part of agricultural SCM, and we hope that next advanced study will continue by using this study.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.300-312
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• 2020

The growing stocks of young forests that are less than10 years of age have been excluded from the Korean forest resource statistics, despite the existence of standing trees; however, sustainable forest management and carbon removals in the forestry section require complete information regarding forest resources. This study developed a method to estimate the growing stocks for young forests from National Forest Inventory (NFI) data. After reviewing previous research on growth characteristics for young forests, we conducted stem analysis of major species, and examined stand characteristics by site index, based on real yield tables. Our statistical analysis results showed that there were few standing trees with diameters at breast height (DBH) above 6 cm in young stands, and that it would have taken 12 years, on average, to reach 6 cm DBH. This suggests that mean tree height by diameter should be assessed at the root, in order to assess growing stocks for young stands through the NFI. Moreover, the database system should be improved to differentiate tree species, since diverse shrubs, including trees, have been surveyed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.287-297
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• 2016

This study aims to identify the relationship between climatic factors and stand mean Diameter at Breast Height (DBH) for two major tree species; Pinus densiflora and Quercus mongolica in Andong-dam basin. Forest variables such as age, diameter distribution and number of trees per hectare from the $5^{th}$ and $6^{th}$ National Forest Inventory data were used to develop a DBH estimation model. Climate data were collected from six meteorological observatory station and twelve Automatic Weather System provided by Korea Meteorological Administration to produce interpolated daily average temperature map with Inverse Distance Weighting (IDW) method. Andong-dam basin reflects rugged mountainous terrain, so temperature were adjusted by lapse rate based correction. As a result, predictions of model were consistent with the previous studies; that the rising temperature is negatively related to the growth of Pinus densiflora whereas opposing trend is observed for Quercus mongolica.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.185-192
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• 2010

The chemical-looping combustion(CLC) has advantages of no energy loss for separation of $CO_2$ without $NO_x$ formation. This CLC system consists of oxidation and reduction reactors where metal oxides particles are circulating through these two reactors. In the present study, the reaction kinetic equations of iron oxide oxygen carriers supported on bentonite have been determined by the shrinking core model. Based on the reactivity data, design values of solid circulation rate and solids inventory were determined for the rector. Two types of interconnected fluidized bed systems were designed for CLC application, one system consists of a riser and a bubbling fluidized bed, and the other one has a riser and two bubbling fluidized beds. Solid circulation rates were varied to about $30kg/m^2s$ by aeration into a loop-seal. Solid circulation rate increases with increasing aeration velocity and it increases further with an auxiliary gas flow into the loop-seal. As solid circulation rate is increased, solid hold up in the riser increases. A typical gas leakage from the riser to the fluidized bed is found to be less than 1%.

• Nuclear Engineering and Technology
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• v.27 no.4
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• pp.470-482
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• 1995

The Ulchin 3&4, which are 2825 MWt PWRs, adopted Safety Depressurization System (SDS) to mitigate the beyond design basis event of Total Less of Feedwater(TLOFW). In this study the results and methodology of the analyses for the determination of SDS bleed capacity are discussed. The SDS design bleed capacity has been determined from the CEFLASH-4AS/REM simulation according to the following design criteria : 1) Each SDS flow path, in conjunction with one of two High Pressure Safety Injection (HPSI) pumps, is designed to have a sufficient capacity to prevent core uncovery if one SDS path is opened simultaneously with the opening of the Pressurizer Safety Valves (PSVs). 2) Both SDS bleed paths are designed to have sufficient total capacity with both HPSI pumps operating to prevent core uncovery if the Feed and Bleed (F&B) initiation is delayed up to thirty minutes from the time of the PSVs lift. To verify the results of CEFLASH-4AS/REM simulation a comparative analysis kas also been per-formed by more sophisticated computer code, RELAP5/MOD3. The TLOFW event without operator recovery and TLOFW event with F&B are analyzed. The predictions by the CEFLASH-4AS/REM of the transient too phase system behavior are in good qualitative and quantitative agreement with those by the RELAP5/MOD3 simulation. Both of the results of analyses by CEFLASH-4AS/REM and RELAP5/MOD3 have demonstrated that decay heat removal and core inventory make-up can be successfully accomplished by F&B operation during now event for the Ulchin 3&4.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.431-440
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• 2019

This study was conducted to investigate changes in activities of daily living (ADLs) according to the Gross Motor Function Classification System (GMFCS) after one year of physical and occupational therapy and to compare the responsiveness of ADL tools. A total of 48 children with spastic cerebral palsy participated in the study. The GMFCS, Functional Independence Measure for Children (WeeFIM), and Pediatric Evaluation of Disability Inventory (PEDI) were measured. The results showed that the GMFCS was significantly correlated with the PEDI (p<0.05), while there was a significant difference in the change of ADLs measured by the PEDI, but not the WeeFIM. There was a significant difference in the changes in ADLs according to the GMFCS, and the change in ADLs in the high functional level group was significantly higher than in the low functional level group (p<0.05). After physical and occupational therapy, the degree of improvement of ADLs varied according to the GMFCS, but seemed to be improved in a clinically meaningfully way. The PEDI is sensitive to changes in ADLs, so it may be used widely in clinical practice.

• Anxiety and mood
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• v.15 no.2
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• pp.101-108
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• 2019

Objective : This study aimed to investigate the associations of anxiety symptoms with behavior and attention in elementary school children with attention-deficit/hyperactivity disorder (ADHD). Methods : A total of 195 elementary school children with ADHD participated in the study. The Korean Version of ADHD Rating Scale (K-ARS) and Behavior Assessment System for Children(BASC-2) were used to measure the children's behavior. Anxiety and attention was assessed with State-Trait Anxiety Inventory for Children (STAIC) and ADHD Diagnostic System (ADS), respectively. Children with ADHD were categorized to two groups of ADHD with low anxiety (ADHD-LA) and ADHD with high anxiety (ADHD-HA) according to the total STAIC scores. Scores on K-ARS, BASC-2 and ADS were compared between two groups of ADHD-LA and ADHD-HA. Results : The Scores on K-ARS total and both subscales in ADHD-HA group were significantly higher than ADHD-LA group. Scores on the BASC-2 subscales including hyperactivity, aggression, conduct problem, anxiety, depression, somatization, withdrawal, attention problems were also significantly higher in ADHD-HA group compared to ADHD-LA group. In contrary, scores on ADS subscales were not significantly different between the both groups. Conclusion : Our study identified that the anxiety accompanied with ADHD was associated with the negative behavioral aspect in children with ADHD. However, the performances on attention task were not affected by the anxiety comorbid with ADHD. Future studies to reveal underlying mechanism are needed for further understanding the association with anxiety and ADHD.

• Journal of Environmental Impact Assessment
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• v.31 no.4
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• pp.214-225
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• 2022

This study emphasized the soil of environmental impact assessment to devise measures to minimize the negative impact of project implementation on the environment. As a series of efforts for impact assessment procedures, a national inventory-based database was established for urban development projects, and three machine learning model performance evaluation as well as soil pollutant concentration distribution mapping were conducted. Here, nine soil pollutants were mapped to the metropolitan area of South Korea using the Random Forest model, which showed the best performance. The results of this study found that concentrations of Zn, F, and Cd were relatively concerned in Seoul, where urbanization is the most active. In addition, in the case of Hg and Cr6+, concentrations were detected below the standard, which was derived from a lack of pollutants such as industrial and industrial complexes that affect contents of heavy metals. A significant correlation between land cover and pollutants was inferred through the spatial distribution mapping of soil pollutants. Through this, it is expected that efficient soil management measures for minimizing soil pollution and planning decisions regarding the location of the project site can be established.