• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.648-657
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• 2021

This study was conducted to estimate the volume growth by forest type and major species using the national forest resource inventory and to predict the final age of maturity by deriving the mean annual increment (MAI) and the current annual increment (CAI). We estimated the volume growth using the Chapman-Richards model. In the volume estimation equations by forest type, coniferous forests exhibited the highest growth. According to the estimation formula for each major species, Larix kaempferi will grow the highest among coniferous tree species and Quercus mongolica among broad-leaved tree species. And these estimation formulas showed that the fitness index was generally low, such as 0.32 for L. kaempferi and 0.21 for Quercus variabilis. In the analysis of residual amount, which indicates the applicability of the volume estimation formula, the estimates of the estimation formula tended to be underestimated in about 30 years or more, but most of the residuals were evenly distributed around zero. Therefore, these estimation formulas have no difficulty estimating the volume of actual forest species in Korea. The maximum age attained by calculating MAI was 34 years for P. densiflora, 35 years for L. kaempferi, and 31 years for P. rigida among coniferous tree species. In broad-leaved tree species, we discovered that the maximum age was 32 years for Q. variabilis, 30 years for Q. acutissima, and 29 years for Q. mongolica. We calculated MAI and CAI to detect the point at which these two curves intersected. This point was defined by the maximum volume harvesting age. These results revealed no significant difference between the current standard cutting age in public and private forests recommended by the Korea Forest Service, supporting the reliability of forestry policy data.

• Korean Journal of Remote Sensing
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• v.37 no.2
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• pp.337-357
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• 2021

Because the growth of paddy rice is affected by meteorological factors, the selection of appropriate meteorological variables is essential to build a rice yield prediction model. This paper examines the suitability of multiple meteorological datasets for the rice yield modeling in South Korea, 1996-2019, and a hindcast experiment for rice yield using a machine learning method by considering the nonlinear relationships between meteorological variables and the rice yield. In addition to the ASOS in-situ observations, we used CRU-JRA ver. 2.1 and ERA5 reanalysis. From the multiple meteorological datasets, we extracted the four common variables (air temperature, relative humidity, solar radiation, and precipitation) and analyzed the characteristics of each data and the associations with rice yields. CRU-JRA ver. 2.1 showed an overall agreement with the other datasets. While relative humidity had a rare relationship with rice yields, solar radiation showed a somewhat high correlation with rice yields. Using the air temperature, solar radiation, and precipitation of July, August, and September, we built a random forest model for the hindcast experiments of rice yields. The model with CRU-JRA ver. 2.1 showed the best performance with a correlation coefficient of 0.772. The solar radiation in the prediction model had the most significant importance among the variables, which is in accordance with the generic agricultural knowledge. This paper has an implication for selecting from multiple meteorological datasets for rice yield modeling.

• (The) Research of the performance art and culture
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• no.20
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• pp.31-61
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• 2010

This thesis proposes to explore the theatre aesthetics of North-Korea during after the Liberation. From now South-Korean theorists have provided the theatre aesthetics of North-Korea to South-Korea, so we can say that it lacks of an equity. For example, South-theorists have said that North-Korean theatre only emphasized politics and propaganda, they have had not any aesthetics in performance. So this study focused on North-Korean critics and records for fairness and as a result something new is founded. The best theatres in North-Korea were some works which contains natural and proper lines to character, well-expressed inner desires of characters, realistic acting and stage design, and realistic life of working class. Of course they should reflect communist ideology and policy, but more important is that it did not mean everything in North-Korea. So we can say that it is fact that North-Korea should reflect their policy, which does not mean lack of aesthetics of performance. North-Korea had an obvious point of view for theatre, and they made an effort to realistic lines, movements and stage. During right after the Liberation, North Korea sought to find an answer for 'realization of true life', and sought to eliminate Japanese acting style in theatre. Concluded theatre aesthetics of North-Korea during right after the Liberation is realistic acting and directing style.

• Food Engineering Progress
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• v.14 no.2
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• pp.166-172
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• 2010

The extraction of polyphenol and flavonoid from citrus peel was performed by the ethanol, sugar, hot water (80$^{\circ}C$), and subcritical water extraction methods. The maximum yields of total polyphenolic compounds (27.25${\pm}$1.33 mg QE/g DCP, QE and DCP indicate quercetin equivalent and dried citrus peel, respectively) and flavonoids (7.31${\pm}$0.41 mg QE/g DCP) were obtained by subcritical water extraction (SWE) with operating conditions of 190$^{\circ}C$, 1300 psi, and 10 min. The yields by SWE were over 7.2-, and 8.5-fold higher than those of total polyphenols (3.79${\pm}$0.73 mg QE/g DCP) and flavonoids (0.86${\pm}$0.27 mg QE/g DCP) obtained using the ethanol extraction, which showed the highest extraction efficiency among tested conventional methods, respectively. Antioxidant activities of extracts obtained by different methods showed no significant differences. However, the relative antioxidant yield per 1 g dried citrus peel by SWE (190$^{\circ}C$, 10 min) was over 9.5-fold higher than that by the ethanol extraction.

• Food Engineering Progress
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• v.14 no.4
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• pp.335-341
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• 2010

The extraction of polyphenol and flavonoid from black rice bran was performed by diverse extraction methods using the sugar solution, ethanol, hot water ($80^{\circ}C$), and by subcritical water extraction (SWE) method. By SWE under operating conditions of $190^{\circ}C$, 1,300 psi, and 10 min, the maximum yields of total polyphenolic compounds (35.06${\pm}$1.28 mg quercetin equivalent (QE)/g dried material and flavonoids (7.08${\pm}$0.31 mg QE/g dried material) could be obtained. These results were over 11.77- and 12.21-fold higher than those of the ethanol extraction, which showed the highest extraction efficiency among tested conventional methods in total polyphenols (2.98${\pm}$0.74 mg QE/g dried material) and flavonoids (0.58${\pm}$0.21 mg QE/g dried material), respectively. Though the highest antioxidant activity (87.14${\pm}$1.14%) was observed at the dried extract obtained from ethanol method, the relative antioxidant activity per 1 g dried black rice bran by SWE ($190^{\circ}C$, 10 min) was over 11.53-fold higher than that by the ethanol extraction.

• The Korean Journal of Archival Studies
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• no.13
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• pp.91-134
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• 2006

In general, personally collected archives, manuscripts, are physically badly conditioned and also contextual of the archives and information on the history of production is mostly collected partly in the manuscripts. Therefore they need to control the name of the producers on the archives collected in various ways effectively and accumulate provenance information which is the key element when understanding the production background in the collecting repository. Here, the authority control and provenance information management must be organized from the beginning of acquisition and this means to collect necessary information considering control process of acquisition as well. This thesis is for verifying the necessity of the authority control in collecting repository and accumulation of the provenance information and for suggesting the things to be considered as collecting Archival authority system. For all these, this thesis shows that it has checked out the necessity of the authority control in archival management and archival authority control and researched the standard of archival authority control, work process and accumulation process. Archival provenance information management and authority control in the archival authority control system are organized through the whole steps of the archival management starting from the lead file to the name of the producers at archival registration and archival description at acquisition. And a lot of information is registered and described at the proper point of time and finally all the information including authority control which controls the Heading in the authority management must be organized to use them as an intellectual management of archives and Finding Aids. The features of the Archival authority system are as follows; first of all, Authority file type which is necessary at the archival authority control of democracy movement is made up of the name of the group, person, affair and terminology(subject name). Second of all, basic record structures and description elements in authority collection of Korea Democracy Foundation Archives apply in the paragraph 1 of ISAAR(CPF) adding some necessary elements and details of description rule such as spacing words and using the periods apply in the paragraph 4 of KCR coping with the features of the archival management system. And also the way of input on the authority record is based on EAC(Encoded Archival Context). Third of all, it made users approach to the sources which they want more easily by connecting the authority terms systemically making it possible to connect the relative terms with up and down words, before and after words variously and concretely expanding the term relations rather than earlier traditional authority system which is usually expressed only with relative words (see also). So the authority control of archival management system can effectively collect and manage the function of various and multiple groups and information on main activities as well as its own function which is controlling the Heading and express the multiple and intermediary relationship between archives and producers or between producers and it also provides them with expanded Record information service which satisfies user's various requests through Indexing service. Finally applying in this international standard ISAAR(CPF) through the instance of the authority management like this, it can be referred to making Archival authority system in Collecting repository hereafter by reorganizing the description elements into appropriate formations and setting up the authority file type which is to be managed properly for every service.

• Journal of Nutrition and Health
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• v.52 no.1
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• pp.36-46
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• 2019

Purpose: This study evaluated amounts of physical activity and sedentary behavior patterns in older adults using an accelerometer and physical activity diary. Methods: Forty-nine older adults (male 26, female 23) participated in this study. They wore a triaxial accelerometer (ActiGraph wGT3X-BT) for one week and wrote a physical activity diary concurrently for three days. Amounts of physical activity, sedentary behavior patterns, and percentage of meeting the World health organization (WHO) physical activity guidelines were analyzed using an accelerometer. In addition, the contents recorded in the physical activity diary were reclassified to 18 levels and the average daily times spent on each level and physical activity level (PAL) were calculated. Results: The subjects were sitting more than half of the day except for bedtime and shower time (59.2%). The numbers of prolonged ${\geq}30$, 40 minutes sedentary bouts were significantly higher in males ($3.10{\pm}1.34$, $1.78{\pm}1.09$, respectively) than in females ($2.34{\pm}1.22$, $1.32{\pm}1.07$, respectively) and the number of breaks per sedentary hour was significantly less in males ($5.74{\pm}0.89$) than in females ($6.44{\pm}0.71$). Among the activities corresponding to sedentary behavior surveyed by the physical activity diary, only the amount of time spent 'resting, speaking and watching TV' showed a significant correlation with the sedentary behavior pattern measured by the accelerometer. The persistence of sedentary behavior was interrupted primarily when low intensity activity was performed. Only 22.4% of the subjects met WHO physical activity guidelines. Conclusion: Based on these results, the physical activity guidelines for older adults should be developed that reflects the appropriate strength, including low activity level and maintenance time of moderate to vigorous physical activity.

• Korean Journal of Child Education & Care
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• v.18 no.4
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• pp.1-25
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• 2018

Purpose: The purpose of this study was to explore about 2-year-old infants' attachment security to a child care teacher and peer play process through a case study. For this purpose, the attachment security was assessed with attachment Q-set to 2-year-old five infants at a day care center in Seoul. Participants of this study are four infants included two infants attached securely to their child care teacher and two infants attached insecurely to their child care teacher. Methods: Participant observation was conducted from April 12 to July 19 in 2018 through 36 observations in free play activities. The Data collected from the transcriptions of video shoots and teachers' interviews, child care plans, and reflexive journal was analyzed and interpreted. Results: The main results of the research were as follows: The beginning of peer play, when infants invited their peers to play, secure attachment infants selected suitable play partners and asked for a specific play behaviors. However, insecure attachment infants invited unsuitable play partners and asked uncertainly play actions to peers. In addition, when infants entered in-progress play, secure attachment infants understood the context of play but insecure attachment infants did not understand the context of play. In the progress of peer play, secure attachment infants cooperated with peers, shared play objects, but insecure attachment infants did not cooperate complementally with peers and express only their opinions. As well, insecure attachment infants could not play harmoniously without child care teacher's interventions. In the end of the peer play, secure attachment infants finished in collaboration with peers but insecure attachment infants failed to finish with the peers and was turned into play with the child care teacher because of peer conflict. Conclusion/Implications: This study has implications for basic resources to think about the role of child care teachers by helping them understand about the relation 2-year-old infants' attachment security to them and peer play process.

• Korean Chemical Engineering Research
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• v.56 no.6
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• pp.871-877
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• 2018

Storing the surplus energy from renewable energy resource is one of the challenges related to intermittent and fluctuating nature of renewable energy electricity production. $CO_2$ methanation is well known reaction that as a renewable energy storage system. $CO_2$ methanation requires a catalyst to be active at relatively low temperatures ($250-500^{\circ}C$) and selectivity towards methane. In this study, the catalytic performance test was conducted using a pressurized bubbling fluidized bed reactor (Diameter: 0.025 m and Height: 0.35 m) with $Ni/{\gamma}-Al_2O_3$ (Ni70%, and ${\gamma}-Al_2O_3$30%) catalyst. The range of the reaction conditions were $H_2/CO_2$ mole ratio range of 4.0-6.0, temperature of $300-420^{\circ}C$, pressure of 1-9 bar, and gas velocity ($U_0/U_{mf}$) of 1-5. As the $H_2/CO_2$ mole ratio, temperature and pressure increased, $CO_2$ conversion increases at the experimental temperature range. However, $CO_2$ conversion decreases with increasing gas velocity due to poor mixing characteristics in the fluidized bed. The maximum $CO_2$ conversion of 99.6% was obtained with the operating condition as follows; $H_2/CO_2$ ratio of 5, temperature of $400^{\circ}C$, pressure of 9 bar, and $U_0/U_{mf}$ of 1.4-3.

• Journal of Wetlands Research
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• v.21 no.1
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• pp.34-42
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• 2019

Baseflow which is one of the unmeasurable components of streamflow and slowly flows through underground is important for water resource management. Despite various separation methods from researches preceded, it is difficult to find a significant separation method for baseflow separation. This study applied the MRC method and developed the improved approach to separate baseflow from total streamflow hydrograph. Previous researchers utilized the whole streamflow data of study period at once to derive synthetic MRCs causing unreliable results. This study has been proceeded with total nine areas with gauging stations. Each three areas are selected from 3 domestic major watersheds. Tool for drawing MRC had been used to draw MRCs of each area. First, synthetic MRC for whole period and two other MRCs were drawn following two different criteria. Two criteria were set by different conditions, one is flow condition and the other is seasonality. The whole streamflow was classified according to seasonality and flow conditions, and MRCs had been drawn with a specialized program. The MRCs for flow conditions had low R2 and similar trend to recession segments. On the other hand, the seasonal MRCs were eligible for the baseflow separation that properly reflects the seasonal variability of baseflow. Comparing two methods of assuming MRC for baseflow separation, seasonal MRC was more effective for relieving overestimating tendency of synthetic MRC. Flow condition MRCs had a large distribution of the flow and this means accurate MRC could not be found. Baseflow separation using seasonal MRC is showing more reliability than the other one, however if certain technique added up to the flow condition MRC method to stabilize distribution of the streamflow, the flow conditions method could secure reliability as much as seasonal MRC method.