• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.206-219
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• 2021

The warming of the climate is increasing the damage caused by termites to wooden buildings, cultural properties and houses. A group removal system can be installed around the building to detect and remove termite damage; however, if the site is not visited regularly, every one to two months, you cannot observe whether termites have spread within, and it is difficult to take prompt effective action. In addition, since the system is installed and operated in an exposed state for a long period of time, it may be ineffective or damaged, resulting in a loss of function. Furthermore if the system is installed near a cultural site, it may affect the aesthetic environment of the site. In this study, we created a detection system that uses wood, cellulose, magnets, and magnetic sensors to determine whether termites have entered the area. The data was then transferred to a low power LoRa Network which displayed the results without the necessity of visiting the site. The wood was made in the shape of a pile, and holes were made from the top to the bottom to make it easier for termites to enter and produce a cellulose sample. The cellulose sample was made in a cylindrical shape with a magnet wrapped in cellulose and inserted into the top of a hole in the wood. Then, the upper part of the wood pile was covered with a stopper to prevent foreign matter from entering. It also served to block external factors such as light and rainfall, and to create an environment where termites could add cellulose samples. When the cellulose was added by the termites, a space was created around the magnet, causing the magnet to either fall or tilt. The magnetic sensor inside the stopper was fixed on the top of the cellulose sample and measured the change in the distance between the magnet and the sensor according to the movement of the magnet. In outdoor experiments, 11 cellulose samples were inserted into the wood detection system and the termite inflow was confirmed through the movement of the magnet without visiting the site within 5 to 17 days. When making further improvements to the function and operation of the system it in the future, it is possible to confirm that termites have invaded without visiting the site. Then it is also possible to reduce damage and fruiting due to product exposure, and which would improve the condition and appearance of cultural properties.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.78-99
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• 2020

The Buddha triad and 16 Arhat statues carved on the rock surface at Seongbulsa temple is the only domestic remaining example of all 16 Arhats, so its academic value is very high. However, it is severely damaged and so required a stability evaluation through study of digital documentation and precise diagnosis for the purpose of comprehensive conservation. This process established that the Buddha statues were of similar scale, while the Arhats showed a wide variety of sizes, and the two kith and kin in the volume were larger than the Arhats. It was estimated that the statues of food for Buddha are similar to the Arhat statues, and most of the statues are well-formed. The rock used to carve the Buddha statues is banded gneiss with distinct foliation, alternating between white bands of quartz and feldspar and black bands composed of biotite. The Buddha statues have been damaged by physical weathering, discoloration, and biological contamination. In damage evaluations, joint (3.6 crack index), peeling (5.2%), exfoliation (1.7%), and falling off (0.1%) were observed on the rock surface of the Buddha statues. In particular, due to severe biological weathering, stage 9 and 10 biological coverage of the rock surface accounted for 57.5% of the total area, and stages 5 to 8 also accounted for a high share at 22.3%. The discoloration factors were shown to be dark brown and white with Fe, Ca, and S, and a large amount of C detected in the blackened contaminants, and the damage weight high in all areas. Discontinuities in different directions were identified in the rock surface. Analysis of potential rock failure types indicated that there is a possibility of plane and toppling failure, but wedge failure is unlikely to occur. The mean ultrasonic velocity of the main rock surface was 2,463m/sec, the lower part of the left side with a large number of joints was relatively low, and the highly weathered (HW) type to the completely weathered (CW) type concentrated distribution, showing weak properties. For the Buddha statues, conservation treatment is required for about 14.9% of micro cracks and 58.9% of exfoliation cracks. In addition, in order to improve the conservation environment of the Buddha statues, maintenance of drainage and ground preparations for the rock surface gradient and plants are necessary, and protection facilities should be reviewed for long-term conservation and management purposes.

• Journal of Bio-Environment Control
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• v.30 no.1
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• pp.1-9
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• 2021

This study was conducted to examine the changes of photosynthesis, growth, chlorophyll contents and functional material contents in light intensity and EC concentration of wild baby leaf vegetable, Indian lettuce (Lactuca indica L. cv. 'Sunhyang') in DFT hydroponics. The cultivation environment was 25±1℃ of temperature and 60±5% of relative humidity in growth system. At 14 days after sowing, combination effect of light intensity (Photosynthetic Photon Flux Density (PPFD 100, 250, 500 µmol·m-2·s-1) and EC level (EC 0.8, 1.4, 2.0 dS·m-1) of nutrient solution was determined at the baby leaf stage. The photosynthesis rate, stomatal conductance, transpiration rate and water use efficiency of Indian lettuce increased as the light intensity increased. The photosynthesis rate and water use efficiency were highest in PPFD 500-EC 1.4 and PPFD 500-EC 2.0 treatment. The chlorophyll content decreased as the light intensity increased, but chlorophyll a/b ratio increased. Leaf water content and specific leaf area decreased as light intensity increased and a negative correlation (p < 0.001) was recognized. Plant height was the longest in PPFD 100-EC 0.8 and leaf number, fresh weight and dry weight were the highest in PPFD 500-EC 2.0. Anthocyanin and total phenolic compounds were the highest in PPFD 500-EC 1.4 and 2.0 treatment, and antioxidant scavenging ability (DPPH) was high in PPFD 250 and 500 treatments. Considering the growth and functional material contents, the proper light intensity and EC level for hydroponic cultivation of Indian lettuce is PPFD 500-EC 2.0, and PPFD 100 and 250, which are low light conditions, EC 0.8 is suitable for growth.

• Journal of Bio-Environment Control
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• v.30 no.1
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• pp.46-55
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• 2021

This experiment was conducted to investigate the effect on chlorophyll fluorescence, stem sap flux relative rate (SFRR) and leaf temperature of cucumber when irrigation is controlled using a soil moisture tensiometer. Cucumber (Cucumis sativus L.) 'Chungchun' was irrigated of 10-10-20 kPa and 20-10-10 kPa by soil starting point of irrigation at each growth stage. At the 66 days after treatment (DAT) of 736 to 854 W·m-2 and above 32℃, chlorophyll fluorescence variables (Fo, Fm, Fv/Fm) values showed significantly different between treatments. The Fo and Fv/Fm value in the daytime (10:30 am to 6:00 pm) at 66 DAT was higher in 20-10-10 kPa treatment than in 10-10-20 kPa treatment. The Fv/Fm value decreased when the leaf temperature was increased. There was no difference in leaf growth (length, width and area) at 28 and 66 DAT, but the chlorophyll content (SPAD value) was significantly higher in 20-10-10kPa treatment. SFRR and leaf temperature increased with light intensity and temperature increased. In both treatments, the SFRR started to increase sharply between 8 am and 9 am when the solar radiation is 170 W·m-2 or higher. The soil temperature of the treatments decreased after irrigation, that showed 31.0℃ at 10-10-20kPa and 28.5℃ at 20-10-10kPa on July 5 (820W·m-2 at 1 pm). However, there was no difference in SFRR, leaf temperature, temperature difference (leaf temperature - air temperature) and VPD between treatments. SFRR was significantly positive correlate with the leaf temperature (p < 0.01, r = 0.770). The SFRR and leaf temperature showed positive significant correlation with solar radiation, temperature, soil temperature, soil moisture content and VPD. There was a negative significant correlation with relative humidity and temperature difference.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.377-386
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• 2021

This study was conducted to provide basic data for habitat management and preservation of Jeongmaek. A total of 18 priority research areas were selected with consideration to terrain and habitat environment, and 54 fixed plots were selected for three types of habits: development, valley, and forest road and ridge. The survey was conducted in each season (May, August, and October), excluding the winter season, from 2016 to 2018. The distribution analysis of birds observed in each habitat type using a self-organizing map (SOM) classified them into a total of four groups (MRPP, A=0.12, and p <0.005). The comparative analysis of the number of species, the number of individuals, and the species diversity index for each SOM group showed that they were all the highest in group III (Kruskal-Wallis, the number species: x² = 13.436, P <0.005; the number of individuals: x² = 8.229, P <0.05; the species diversity index: x² = 17.115, P <0.005). Moreover, the analysis by applying the land cover map to the random forest model to examine the index species of each group and identify the characteristics of the habitat environment showed a difference in the ratio of the habitat environment and the indicator species among the four groups. The index species analysis identified a total of 18 bird species as the indicator species in three groups except for group II. When applying the random forest model and indicator species analysis to the results of classification into four groups using the SOM, the composition of the indicator species by the group showed a correlation with the habitat characteristics of each group. Moreover, the distribution patterns and densities of observed species were clearly distinguished according to the dominant habitat for each group. The results of the analysis that applied the SOM, indicator species, and random forest model together can derive useful results for the characterization of bird habitats according to the habitat environment.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.198-221
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• 2021

After large-scale reforestation in the 1960s and 1970s, forests in Korea have gradually been aging. Net ecosystem CO₂ exchange of old-growth forests is theoretically near zero; however, it can be a CO₂ sink or source depending on the intervention of disturbance or management. In this study, we report the CO₂ budget dynamics of the Gwangneung deciduous old-growth forest (GDK) in Korea and examined the following two questions: (1) is the preserved GDK indeed CO₂ neutral as theoretically known? and (2) can we explain the dynamics of CO₂ budget by the common mechanisms reported in the literature? To answer, we analyzed the 15-year long CO₂ flux data measured by eddy covariance technique along with other biometeorological data at the KoFlux GDK site from 2006 to 2020. The results showed that (1) GDK switched back-and-forth between sink and source of CO₂ but averaged to be a week CO₂ source (and turning to a moderate CO₂ source for the recent five years) and (2) the interannual variability of solar radiation, growing season length, and leaf area index showed a positive correlation with that of gross primary production (GPP) (R²=0.32~0.45); whereas the interannual variability of both air and surface temperature was not significantly correlated with that of ecosystem respiration (RE). Furthermore, the machine learning-based model trained using the dataset of early monitoring period (first 10 years) failed to reproduce the observed interannual variations of GPP and RE for the recent five years. Biomass data analysis suggests that carbon emissions from coarse woody debris may have contributed partly to the conversion to a moderate CO₂ source. To properly understand and interpret the long-term CO₂ budget dynamics of GDK, new framework of analysis and modeling based on complex systems science is needed. Also, it is important to maintain the flux monitoring and data quality along with the monitoring of coarse woody debris and disturbances.

• Journal of Nutrition and Health
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• v.55 no.1
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• pp.155-173
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• 2022

Purpose: This study was undertaken to update the Nutrition Quotient for Elderly (NQ-E), which reflects dietary quality and behavior among Korean older adults. Methods: The first 29 items of the measurable food behavior checklist were obtained from a previous NQ-E checklist, recent literature reviews, and national nutrition policies and recommendations. One-hundred subjects (50 men and 50 women) aged ≥ 65 years living in the Seoul Metropolitan Area, including Gyeonggi Province, completed a pilot survey from March to April 2021. Based on the results of the pilot study, we conducted factor analysis and frequency analysis to determine whether the items of the survey were properly organized and whether the distribution of answers for each evaluation item was properly distributed. As a result, we reduced the number of items on the food behavior checklist and used 23 items for the national survey. Nationwide, 1,000 subjects (472 men and 528 women) aged > 65 years, completed the checklist survey, which was applied using a face-to-face survey method from May to August 2021. The construct validity of the NQ-E 2021 was assessed using confirmatory factor analysis, LISREL. Results: Seventeen food behavior checklist items were selected for the final NQ-E 2021. Checklist items addressed three factors: balance (8 items), moderation (2 items), and practice (7 items). Standardized path coefficients were used as the weights of items to determine nutrition quotients. NQ-E and three-factor scores were calculated according to the weights of questionnaire items. Conclusion: The updated NQ-E 2021 produced by structural equation modelling provides a suitable tool for assessing the dietary quality and behavior of Korean older adults.

• Korean Journal of Environment and Ecology
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• v.35 no.6
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• pp.609-620
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• 2021

This study surveyed six national parks that included a wide range of afforestation among national parks in Korea to analyze the vegetation structure of Larix kaempferi, which occupies the highest ratio among planted areas. Plots were established considering the dominant ratio, diameter at breast height and afforestation area of Larix kaempferi. The purpose of the study was to provide basic data for ecological management to promote diversity. A total of 51 plots were selected based on 400 m² quadrates. TWINSPAN was used for community classification, and each classified community was analyzed of importance percentage, species diversity, number of species, and populations. The community classification identified7 communities, all dominated by Larix kaempferi in the tree layer and classified by the appearance species of the subtree layer and shrub layer. In communities I, II, and VII that are located in the valley, Zelkova serrata, Morus bombycis, and Fraxinus rhynchophylla appeared, while dominated by Larix kaempferi were in the tree layer. Wetland deciduous broad-leaved species such as Fraxinus rhynchophylla and Morus bombycis frequently appeared in the subtree layer. In community III through VI is located on the slope, Quercus spp., such as Quercus mongolica and Quercus acutissima, mainly appeared while dominated by Larix kaempferi in the tree layer, and Quercus and wetland broad-leaved species frequently appeared in the subtree layer and shrub layer. The average species diversity of Larix kaempferi in the surveyed six national parks was 1.2090, with community III the highest at 1.5413 and community VI the lowest at 0.7042. The average number of species was 9.35±2.90, and the average population was 226.05±89.98.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.1
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• pp.55-64
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• 2022

This study aims to shed light on the cultural history of Hajodae(河趙臺) enjoyed by writers of the Joseon Dynasty by analyzing the origin and the contents of the landscape based on the literature materials of Hajodae in Yangyang(襄陽). The results of the study are as follows. First, Hajodae is a space that is said to have been visited by Ha Ryun(河崙) and Jo Jun(趙浚). However, since this story has not been confirmed in the literature, various opinions coexisted in history. Jo Wi-Han(趙緯韓) quoted the opinions of aged people who lived in Yangyang, saying that it could be Jo In-Byeok(趙仁壁), not Jo Jun(趙浚), and Jo Deok-Rin(趙德鄰) recorded it as "遐眺臺", which means "a stand for a distance view." There is a need to clearly present the origin of Hajodae by revealing the literary authority. Second, Hajodae was talked about as the best scenic site in Gwandong(關東) in the middle of the Joseon Dynasty. during the mid-Joseon Dynasty. The writers of the time mentioned Hajodae as one of the best scenic sites in Gwandong, which soon became a symbol of Yangyang. These records of Hajodae show a relatively decreasing trend entering the late Joseon Dynasty. It is believed to be the result of the slight degrading in the status of Hajodae as the Eight Views of Gwandong were established and Naksansa Temple(洛山寺) gained fame. Third, the writers of Joseon enjoyed the scenic sites through various landscapes of Hajodae. The open terrain on three sides allowed a sea view and provided an opportunity to develop a great spirit or to reflect on oneself. On the other hand, the strange rock formations and cliffs, which correspond to a close-up view, drew the attention of tourists, and the Rosa rugosa Thunb. blooming in the Hajodae area was enough to show a bizarre charm. This shows the various charms of Hajodae, suggesting that the management of such landscape is necessary. Fourth, a Chinese poem about Hajodae shows the spatial meaning of Hajodae. Looking into all sides of the Chinese poem about Hajodae, a case of unburdening one's mind on the landscape, and the aspect a person compared oneself to the natural landscape or projected one's consciousness onto it, and a case of recalling Ha Ryun and Jo Jun, illustrious retainers in the early Joseon Dynasty are confirmed. It can be seen that it results in the aspect of expressing one's impressions and looking back on history through the landscape.

• Korean Journal of Remote Sensing
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• v.38 no.6_2
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• pp.1723-1735
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• 2022

Landslides are one of the most prevalent natural disasters, threating both humans and property. Also landslides can cause damage at the national level, so effective prediction and prevention are essential. Research to produce a landslide susceptibility map with high accuracy is steadily being conducted, and various models have been applied to landslide susceptibility analysis. Pixel-based machine learning models such as frequency ratio models, logistic regression models, ensembles models, and Artificial Neural Networks have been mainly applied. Recent studies have shown that the kernel-based convolutional neural network (CNN) technique is effective and that the spatial characteristics of input data have a significant effect on the accuracy of landslide susceptibility mapping. For this reason, the purpose of this study is to analyze landslide vulnerability using a pixel-based deep neural network model and a patch-based convolutional neural network model. The research area was set up in Gangwon-do, including Inje, Gangneung, and Pyeongchang, where landslides occurred frequently and damaged. Landslide-related factors include slope, curvature, stream power index (SPI), topographic wetness index (TWI), topographic position index (TPI), timber diameter, timber age, lithology, land use, soil depth, soil parent material, lineament density, fault density, normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) were used. Landslide-related factors were built into a spatial database through data preprocessing, and landslide susceptibility map was predicted using deep neural network (DNN) and CNN models. The model and landslide susceptibility map were verified through average precision (AP) and root mean square errors (RMSE), and as a result of the verification, the patch-based CNN model showed 3.4% improved performance compared to the pixel-based DNN model. The results of this study can be used to predict landslides and are expected to serve as a scientific basis for establishing land use policies and landslide management policies.