• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.235-242
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• 2018

BACKGROUND: About 81% of nitrous oxide ($N_2O$) emissions from agricultural land to the atmosphere is due to nitrogen (N) fertilizer application. Mitigation of $N_2O$ emissions can be more effective in controlling biochemical processes such as nitrification and denitrification in the soil rather than decreasing fertilizer application. The use of urease inhibitors is an effective way to improve N fertilizer efficiency and reduce $N_2O$ emissions. Several compounds act as urease inhibitors, but N-(n-butyl) thiophosphoric triamide (NBPT) has been used worldwide. METHODS AND RESULTS: Hot pepper and chinese cabbage were cultivated in five treatments: standard fertilizer of nitrogen-phosphorus-potassium(N-P-K, $N-P_2O_5-K_2O$: 22.5-11.2-14.9 kg/ha for hot pepper and $N-P_2O_5-K_2O$: 32.0-7.8-19.8 kg/ha for chinese cabbage), no fertilizer, and NBPT-treated fertilizer of 0.5, 1.0, and 2.0 times of nitrogen basal application rate of the standard fertilizer, respectively in Gyeonggi-do Hwaseong-si for 2 years(2015-2016). According to application of NBPT-treated fertilizer in hot pepper and chinese cabbage, $N_2O$ emission decreased by 19-20% compared to that of the standard fertilizer plot. CONCLUSION: NBPT-treated fertilizer proved that $N_2O$ emissions decreased statistically significant in the same growth conditions as the standard fertilization in the hot pepper and chinese cabbage cultivated fields. It means that NBPT-treated fertilizer can be applied for N fertilizer efficiency and $N_2O$ emissions reduction.

• Journal of Climate Change Research
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• v.4 no.4
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• pp.409-416
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• 2013

Recently, the property damage has been increasing due to climate change in South Korea. While the general public has become more aware of the environmental issues, but the environmental education system has not been able to meet up with the demands of the public. The purpose of this study is to suggest preliminary data which is needed for developing a environmental textbook. A survey was conducted to meet the following requirements. Respondent's level of interest in problems or situations concerning the following eight themes: fundamental science, health and medicine, aerospace engineering, life science, electrical electronics, telecommunication, mineral and energy resources, environment. The data was collected from 139 students in Seoul and Gyeonggi province. The results showed that health and medicine issues interest students the most (49.6%), followed by environment (46.8%). We asked the respondents who were very interested in each question for their reasons, and they answered that environmental issue is related to the improvement of their life quality (53.8%) than their curiosity (38.5%). Students were very interested in the other issues because of just curiosity. Most students (90.6%) said seasonal change was not same each year. 18.0% of respondents replied that they and their friends had experienced climate change. The majority of students (94.2%) thought that they will experience natural disaster blamed on climate change during their life. In other words, climate change is already the day-to-day events of their lives. The majority of their opinions, more then three than ten students(30.9%) said the South Korean government should conduct an energy saving campaign to climate change problems followed by expanding new renewable energy (24.5%), conducting adaptation policies of climate change(22.3 %), introducing of a system as like $CO_2$ emissions trading(20.9%) and so on. There are more Stu- dents (69.1%) who know of new renewable energy than students who don't know it; however, respondents who know the meaning very well were just 18.7% showing that most students dimly know the meaning of new renewable energy.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.46-54
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• 2019

Experiments of local cooling and heating on crown and root zone of forcing cultivation of strawberry 'Seolhyang' using heat pump and root pruning before planting were conducted. During the daytime, the crown surface temperature of the crown local cooling treatment was maintained at $18{\sim}22^{\circ}C$. This is suitable for flower differentiation, while those of control and root zone local cooling treatment were above $30^{\circ}C$. Budding rate of first flower clusters and initial yields were in the order of crown local cooling, root zone local cooling and control in root pruning plantlet and non pruning plantlet, except for purchase plantlet. Those of root pruning plantlet were higher than those of non pruning plantlet. These trends were evident in the yield of the first flower cluster until February 14, 2018, and the effect of local cooling and root pruning decreased from March 9, 2018. The budding rates of the second flower cluster according to the local cooling and root pruning treatments were not noticeable compared to first flower cluster but showed the same tendency as that of first flower cluster. In the heating experiment, root zone local heating(root zone $20^{\circ}C$+inside greenhouse $5^{\circ}C$) and crown local heating(crown $20^{\circ}C$+inside greenhouse $5^{\circ}C$) saved 59% and 65% of heating fuel, respectively, compared to control(inside greenhouse $9^{\circ}C$). Considering the electric power consumption according to the heat pump operation, the heating costs were reduced by 55% and 61%, respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.83-91
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• 2019

The purpose of this study is to assess a fire-damaged concrete structure using a digital camera and image processing software. To simulate it, mortar and paste samples of W/C=0.5(general strength) and 0.3(high strength) were put into an electric furnace and simulated from $100^{\circ}C$ to $1000^{\circ}C$. Here, the paste was processed into a powder to measure CIELAB chromaticity, and the samples were taken with a digital camera. The RGB chromaticity was measured by color intensity analyzer software. As a result, the residual compressive strength of W/C=0.5 and 0.3 was 87.2 % and 86.7 % at the heating temperature of $400^{\circ}C$. However there was a sudden decrease in strength at the temperature above $500^{\circ}C$, while the residual compressive strength of W/C=0.5 and 0.3 was 55.2 % and 51.9 % of residual strength. At the temperature $700^{\circ}C$ or higher, W/C=0.5 and W/C=0.3 show 26.3% and 27.8% of residual strength, so that the durability of the structure could not be secured. The results of $L^*a^*b$ color analysis show that $b^*$ increases rapidly after $700^{\circ}C$. It is analyzed that the intensity of yellow becomes strong after $700^{\circ}C$. Further, the RGB analysis found that the histogram kurtosis and frequency of Red and Green increases after $700^{\circ}C$. It is analyzed that number of Red and Green pixels are increased. Therefore, it is deemed possible to estimate the degree of damage by checking the change in yellow($b^*$ or R+G) when analyzing the chromaticity of the fire-damaged concrete structures.

• Korean Journal of Heritage: History & Science
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• v.46 no.2
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• pp.70-95
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• 2013

The Tejaprabha Buddha painting, located in the Korai Museum in Kyoto, Japan, was made in 1569 when Joseon Dynasty was in his $14^{th}$ year under SeonJo's ruling, and is only one of Tejaprabha Buddha paintings from the early Chosun dynasty. With its well preserved state, the painting allows clear indications of all icons and list of names that were written, and the record region also has minimal deterioration. This Buddhist painting is a GumSeonMyoHwa which is drawn with gold lining on red hemp cloth and has a relatively small dimension of $84.8{\times}66.1cm$. With the Tejaprabha Buddha in the center, the painting has two unidentified Bodhisattvas, Navagrabha, Rahu, Keto, YiSipPalSoo (28 constellation of the eastern philosophy), SipYiGoong (12 zodiacs of the western philosophy), SamDaeYookSung, and BookDooChilSung (the Big Dipper), all of which provide resourceful materials for constellation worshipin the Joseon era. This painting has a crucial representation of the overall Tejaprabha Buddhism - a type of constellation worships - from the early Joseon dynasty. Even though the composition does seem to be affiliated with the paintings from the Koryo dynasty, there are meaningful transformations that reflect changes in content into constellation worship in Joseon dynasty. As a part of the Tejaprabha Buddha, SipIlYo has become a center of the painting, but with reduced guidance and off-centered 'Weolpe (star)', the painting deteriorates the concept of SipIlYo's composition. Furthermore, addition of Taoistic constellation beliefs, such as JaMiSung (The purple Tenuity Emperor of the North Pole), OkHwangDaeChae, and CheonHwangJae, eliminates the clear distinction between Taoistic and Buddhist constellation worships. Unlike the Chinese Tejaprabha Buddha painting, the concept of YiSipPalSoo (28 constellation of eastern philosophy) in this painting clearly reflects Korean CheonMoonDo's approach to constellation which can be applied to its uniqueness of the constellation worships. The fact that the Big Dipper and ChilWonSungKoon (Buddha of the Root Destiny Stars of the Northern and central Dipper) are simultaneously drawn can also be interpreted as the increase in importance of the constellation worship at the time as well.

• Korean Journal of Heritage: History & Science
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• v.46 no.1
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• pp.268-289
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• 2013

The Dinosaur tracksite at Jeori, Geumseongmyeon, Euiseonggun, Gyeongsangbukdo, Korea (National Monument No. 373) has been studied in the aspects of location, stratigraphy, sedimentology, fossil occurrence, unique geological records, literature, significance in natural history, preservation, and management. On the basis of these features, the Jeori tracksite has been assessed semiquantitavely. The Jeori tracksite occurs in the Sagok Formation (Albian) of the Euiseong sub-basin, and over 300 footprints forming 12 sauropod trackways, 10 ornithopod trackways, and 1 theropod trackways are preserved in this tracksite. The track-bearing deposits consist of tabular-bedded medium- to fine-grained arkose with mudstone drape, interlaminated fine-grained sandstone to siltstone and mudstone, and shaly mudstone. The dinosaur tracks are preserved in the interlaminated fine-grained sandstone to siltstone and mudstone, and most of them are observed as underprints. The track-bearing deposits are interpreted as sheetflood deposits on the floodplain under a seasonal paleoclimatic condition with alternating of wetting and drying periods. Multiple tension fractures with NE strike were formed in the track-bearing bed, which resulted in that tracks seem to occur in several horizons. The significance in natural history of the tracksite can be summarized as follows: 1) the historical implication of the Jeori tracksite as the firstly designated National Monument of dinosaur fossil sites, 2) the high density of the occurrence of diverse footprints (over 300) within small area (about $1,600m^2$), and 3) the significance of the tension fractures associated with the track-bearing bed as geoeducational records for the understanding the development of fault. In order to share the value of the Jeori tracksite in the aspect of natural history with the community and public, the interpretive panel should be modified to include figures explaining paleoenvironment and tension fault development. In addition it is recommended that a brochure be published briefly explaining the tracksite and to educate the residents about the natural and social significance of the tracksite. For the safety of visitors it would be desirable for the road in front of the tracksite to be moved at least 10 m southward, which could mitigate the shaking of the track bed caused by traffic.

• Korean Journal of Heritage: History & Science
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• v.42 no.4
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• pp.198-221
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• 2009

Royal tombs of Joseon dynasty are the crystallization of history, ideology, culture, art, architecture, and ritual ceremony of Joseon dynasty, all mingled in one. So, they are very significant symbols showing 500 years of dynastic history as a whole. Among various factors comprising a royal tomb, stone figures surrounding grave mound are special factors as a symbol protecting it. Further among them, twelve zodiac images arrayed nearest to the grave mound represent the core of the function. Images of twelve zodiac signs originated from the tombs of the Unified Silla Kingdom are certain to hold important role and position in the construction of royal tombs, judging from huge scale and excellent sculptural art of them. However, both their scale and form had been gradually simplified in Goryeo and Joseon dynasty, thus the importance of them has been underestimated compared to other stone figures Images of twelve zodiac signs were very important factors which decorated royal tombs both as a protective role and as a concept of direction. Their historicity and symbolism cannot be neglected in that they had been transmitted to the royal tombs of Joseon dynasty. In this paper, images of twelve zodiac signs expressed in the royal tombs of Joseon dynasty are classified into 3 forms, and reviewed the origin and development of them for each period. They could be classified into 3 forms ; civil vassals with human body and head, civil vassals with human body and head wearing hat decorated with zodiac animals, Chinese characters of either zodiac signs or either a combination of 10 calendar signs and 8 trigrams. The above 3 forms originated from China and became a favorite motif to decorate the royal tombs from early Joseon period until late Joseon by replacing each other and thus changing along the course of the dynasty. In the meantime, we can see a unique character in the images of twelve zodiac signs of royal tombs of Joseon dynasty. In some cases, 24 directions are expressed in which 10 calender signs and 8 trigrams are composed altogether. Images of twelve zodiac signs in the royal bombs of Joseon dynasty are very significant as evidences by which we can confirm uniqueness and tradition of Korean tomb system transmitted from Unified Silla period.

• Korean Journal of Heritage: History & Science
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• v.47 no.2
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• pp.46-67
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• 2014

The Dinosaur track-bearing deposits recently found at Bangudae Petroglyph site in Ulju (National Treasure No. 285) have been studied in the aspects of sedimentology, paleoenvironments, and significance in natural history. The dinosaur tracks occur in the Daegu Formation (late Early Cretaceous), and over 80 footprints including 43 ornithopod footprints, 36 sauropod footprints, and 2 theropod footprints are preserved in this tracksite. The track-bearing deposits consist of irregularly interlaminated siltstone and mudstone, calcareous sandy to silty mudstone, thin-bedded tuffaceous sandstone, planar- to cross-laminated sandstone, and thin- to medium-bedded graded sandstone, and they are interpreted to be sheetflood deposits on an alluvial plain. Diverse types of ripples and mudcracks, rainprints, and invertebrate trace fossils are observed in these deposits, and the crest-lines of wave ripples do not show preferred orientation. Dinosaur footprints occur as true prints, underprints, overtracks, and casts on the bedding surfaces, and the orientation of trackways are scattered. It is interpreted that paleoclimatic condition of the track-bearing deposits were semiarid with alternation of wetting and drying periods, and that dinosaurs frequented small and shallow ponds during wetting periods and recorded their tracks on an alluvial plain. The frequent occurrence of dinosaur tracks in study area indicates that the Cretaceous deposits around Daegokcheon Stream are very useful sedimentological and paleontological records to understand the paleoecology and paleoenvironments during the dinosaur age in Korean Peninsula. Consequently the dinosaur track-bearing deposits around Daegokcheon Stream should be further studied in sedimentary geology and paleontology in order to enhance cultural heritage value of the Petroglyphs of Bangudae Terrace as the World Heritage.

• Korean Journal of Heritage: History & Science
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• v.40
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• pp.357-386
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• 2007

At present, thirteen Buddhist bells of Unified Silla are known to the world: Six in Korea, five in Japan and two other bells, and three out of them are impossible to make out its original form. Therefore, we divided the form of Unified Silla Buddhist bells based on the ten other bells, and we tried out to prove the manufacturing technology by the comparison of the research material of Uncheon-dong bell and existing research materials of other bells, in other to find their linkage based on the alloy elemental composition. We divided Unified Silla Buddhist bell into two types: Type I has symmetric apsaras and regular patterns on its face and it was made in early Silla period; type II has asymmetric apsaras and irregular pattern arrangement and made in late Silla period. In particular, Uncheon-dong Buddhist bells is very similar to Komyoji[光明寺] temple bell from ninth century in Japan. It is peculiar that the apsaras on Uncheon-dong bell play vertical music instruments that are never seen in Unified Silla Buddhist bell. Most of Unified Silla Buddhist bell are compounded with Cu-Sn or Cu-Sn-Pb system. From eighth and ninth century, bells were cast with even composition of copper, tin and lead, and the bronze alloy ratio was similar to the record in Gogonggi[考工記], Jurye[周禮], a book from ancient China. Particularly, Uncheon-dong bell is in a rare case of Cu-Sn-Pb-As system. As had been rarely used in Unified Silla Buddhist bells, so we presented the relative research materials. As has the same nature as Pb. Because As easily volatilize at high temperature, it is hard to use. But it has its merit of solidity and durability. Pb enhances fluidity and thereby expresses the patterns more distinct; As makes the bell stronger. The result of lead isotope ratio could not exactly reveal a concrete producing center. However, over the analysis of our samples, hereby we suggest Uncheon-dong bell was made of materials from just one ore deposit.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.165-178
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• 2021

Owing to the lack of consistent research on endangered plant species in Korea, there are insufficient data to preservespecies and expand habitats. This study analyzed the preferred habitat and threats to the survival of Aconitum austrokoreense, found on Baekwun Mountain in Gurye-gun, Gwangyang-si, Jeollanam-do Province, and classified as a level two endangered wild plant by the Ministry of Environment, by investigating major environmental factors such as climate, location, soil, and stand structure. By examining five selected sites inhabited by Aconitum austrokoreense on BaekwunMountain, this study found that the habitat had an altitude of 420 to 675 m above sea level and showed a northeast tendency, spreading over a range of inclination angles between 15° and 37°. The average number of plants across the five sites was 156. Site 4 (550 m) had the highest density of 372 plants, with an average height of 0.6 m. The average soil moisture and relative light intensity were 20.48% and 7.34%, respectively. Layer soil was presumed to be sandy loam, characterized by high sand content and good drainage. The habitat had average soil pH of 5.2, average organic matter of 16.46%, average nitrogen of 0.86%, average available phosphate of 11.86 mg/kg, average electrical conductivity of 0.44 dS/m, and average cation exchange capacity of 37.04 cmolc/kg. The total carbon in soil averaged 10.68%. From the analysis of the vegetation structure of sites inhabited by Aconitum austrokoreense, the dominant populations were Pinus koraiensis and Lindera erythrocarpa in Site 1, Magnolia obovata and Carpinus laxiflora in Site 2, Zelkova serrate and Quercus variabilis in Site 3, Staphylea bumalda and Lindera erythrocarpa in Site 4, and Morus bombycis,Styrax japonicus, and Carpinus laxiflora in Site 5. With most habitats located near trails and sap collection sites of Acer pictum, the species were exposed to artificial damage and interference threats.