• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.413-422
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• 2022

Barnea manilensis is a bivalve which bores soft rocks, such as, limestone or mudstone in the low intertidal zone. They make burrows which have narrow entrances and wide interiors and live in these burrows for a lifetime. In this study, the morphology and the microstructure of the valve of rock-boring clam B. manilensis were observed using a stereoscopic microscope and FE-SEM, respectively. The chemical composition of specific part of the valve was assessed by energy dispersive X-ray spectroscopy (EDS) analysis. 3D modeling and structural dynamic analysis were used to simulate the boring behavior of B. manilensis. Microscopy results showed that the valve was asymmetric with plow-like spikes which were located on the anterior surface of the valve and were distributed in a specific direction. The anterior parts of the valve were thicker than the posterior parts. EDS results indicated that the valve mainly consisted of calcium carbonate, while metal elements, such as, Al, Si, Mn, Fe, and Mg were detected on the outer surface of the anterior spikes. It was assumed that the metal elements increased the strength of the valve, thus helping the B. manilensis to bore sediment. The simulation showed that spikes located on the anterior part of the valve received a load at all angles. It was suggested that the anterior part of the shell received the load while drilling rocks. The boring mechanism using the amorphous valve of B. manilensis is expected to be used as basic data to devise an efficient drilling mechanism.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.1
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• pp.10-16
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• 2022

This study was conducted to examine the dry matter yield and weed control of alfalfa according to postemergence herbicides treatment during spring seeding alfalfa. The seeding time of alfalfa was April 21, 2021, the seeding amount was 20 kg/ha, and the seeding method was by 20 cm wide. The alfalfa harvest was carried out at the early bloom stage (10% of flowering), and the harvest date was June 29, 2021. The test treatments were non herbicide (NH), hand weeding (HW), herbicide 1 (Trifluralin, H1), herbicide 2 (S-metolachlor, H2), herbicide 3 (Alachlor, H3), and herbicide 4 (Pendimethalin, H4). Alfalfa plant height was significantly highest in H2 (62.1±1.4 cm) followed by H3 (61.7±1.6 cm), HW (58.5±1.0 cm), H1 (57.2±1.3 cm), H4 (56.1±1.3 cm), and NH (54.1±1.2 cm) (p<0.05). Based on HW, H2 and H3 were high and H1 and H4 were short, but NH was significantly shorter than HW and H1~H4 (p<0.05). The dry matter yield of alfalfa in NH, HW, H1, H2, H3, and H4 were 717.2±94.2, 2,613.8±254.1, 1,667.8±94.1, 2,498.3±120.2, 2,435.0±118.3, and 1,793.7±354.3 kg/ha. HW is the highest among them (p<0.05). The feed composition of alfalfa was 22~24% of the dry matter yield, and the CP content were significantly higher in NH (23.6 %) (p<0.05). The NH had higher (p<0.05) NDF and ADF, but RFV was lower (p<0.05). The weed plant height was NH 98.0±3.3cm, HW 73.3±1.7 cm, H1 91.9±1.5 cm, H2 53.3±5.8 cm, H3 81.4±3.5 cm and H4 96.6±2.2 cm, and H2 was significantly smallest in the group (p<0.05). The weed dry matter yield was NH 4,770.4±232.5 kg/ha, HW 316.3±91.9 kg/ha, H1 2,353.4±173.7 kg/ha, H2 114.5±10.2 kg/ha, H3 752.7±440.6 kg/ha and H4 2,220.6±775.6 kg/ha. The weed control value was HW 94.1%, H1 53.5%, H2 98.2%, H3 84.9%, H4 48.7%, the weed value of H2 is similar to weed control value of HW. Considering the above results, postemergence herbicide treatment controlled weeds by more than 50% compared with no treatment, and among herbicides, H2 (S-metolachlor) was found to be on a similar level to hand weeding.

• Journal of Life Science
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• v.32 no.3
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• pp.202-209
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• 2022

The green alga Chlamydomonas reinhardtii, a unicellular haploid eukaryote, has long been used by researchers and industries as a cell factory to produce high value-added microalgae substances using genetic modification. Microalga K01, presumed to be Chlamydomonas, was isolated from 12 freshwater samples from the Chungcheong and Jeolla regions to replace C. reinhardtii, an introduced species currently used in most basic and industrial research. The isolated K01 strain was identified as C. reinhardtii through morphological and phylogenetic studies of the 18S rDNA gene sequence (NCBI accession number KC166137). The growth and lipid content of the isolated C. reinhardtii K01 were compared with three wild and four mutant strains in TAP medium, and it was found that the K01 strain could produce 1.74×10⁷ cells/ml by the third day of culture. The growth rate of C. reinhardtii K01 was 1.5 times faster than UTEX2244, which showed the highest number of cells (1.20×10⁷ cells/ml) among the compared strains. The lipid content of the isolated C. reinhardtii K01 (20.67%) was similar to those of the wild strains, although the fatty acid oleate C18:1 was not detected in the isolated strain but was identified in the seven others. The cell density of the isolated strain increased to 0.87 g/l during a six-day culture in BG11 medium, where nitrate (NaNO₃) was introduced as a nitrogen source, while the seven acquired strains showed almost no cell proliferation.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.427-434
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• 2022

This study aims to develop design elements for cultural convergence between rehabilitation for individuals with developmental disabilities and lifelong education for individuals with disabilities, which is a key area in the practical support system for independent life support for individuals with developmental disabilities. As for the research method, a procedure for conducting FGI by forming two teams for professors majoring in special education and rehabilitation science was formed. The research was presented in three upper categories (universal cultural convergence elements, field-centered cultural convergence elements, and policy-centered cultural convergence elements) that should be designed for cultural convergence between rehabilitation for individuals with developmental disabilities and lifelong education for individuals with disabilities. In addition, subcategories were specifically composed for each upper category. First, as a universal cultural element, "open creative convergence" was presented in principle, which can be explained as a principle of exploring and practicing the validity of convergence between related fields for rehabilitation for individuals with developmental disabilities and lifelong education for individuals with disabilities. Second, field-centered cultural factors included development of joint practice model between fields of rehabilitation science and special education, subject matter education knowledge and skills, teaching and learning methods, learning career roadmaps, employment and job career development roadmaps, and the formation of an independent life development history certification system. Third, as policy-centered cultural elements, the formation of a curriculum integration composition system between local related institutions, the establishment of a qualification development path for coordinator-professional teacher-type personnel, and the organizational systematization between school-center types were presented. The study concluded that independent life support for individuals with developmental disabilities should not only be guaranteed for the entire life of adulthood, but also a lifelong education for individuals with disabilities based rehabilitation support system for individuals with developmental disabilities should be established through cultural convergence.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.10-18
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• 2022

This study analyzed the relationship between the community structure of benthic macroinvertebrates and habitat changes in open estuaries among the sites included in the national estuary monitoring program. The estuary survey was conducted under the "Guidelines for Investigation and Evaluation of Biometric Networks" and classified by sea area, 80 places in the East Sea, 102 places in the South Sea, and 19 places in the West Sea were investigated. In a total of 201 open estuaries, benthic macroinvertebrates were identified with 4 phyla, 9 classes, 41 orders, 139 families, 269 species and 196 species in the East Sea, 182 species in the South Sea, and 90 species in the West Sea. The highest population densities were Insecta in the East Sea, the Malacostraca in the South Sea, and the Annelida in the West Sea. Through SIMPER analysis, species contributing to the similarity of benthic macroinvertebrates communities in each sea area were identified. Some species greatly influenced the similarity of clusters. The benthic community in the East Sea was affected by the salinity, so the contribution rate of freshwater species was high. On the other hand, the benthic communities of the South and West Seas showed species compositions are influenced by the substrate composition. As results, the benthic macroinvertebrate community in Korean estuaries was impacted by salinity and substrate simultaneously, and the close relationship with geographical distance was not observed. The result of this study is expected to be used to respond to environmental changes by identifying and predicting changes in the diversity and distribution of benthic macroinvertebrates in Korea estuaries.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.69-80
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• 2023

This study investigated the differences in barley growth at different growth stages (Dec, Feb, and Apr) and the yield at harvest in three groups (G1, G2, and G3) with different climates. Additionally, we measured meteorological differences between areas during the growing season to determine which factors were related to growth and yield differences. We evaluated the chemical composition of soil and the mineral content in leaves during the heading stages. We also recorded the main constituents, amino acids, and mineral compositions of barley seeds grown in different areas. Tiller number/m² in G1 areas was higher than in G2 and G3 when measured before and after overwintering. However, tiller number/m² and dry aboveground plant parts/m² in G2 and G3 areas were higher than in G1. Regrowth, panicle formation, and heading days in G2 areas occurred slightly later than in G1 and G3. However, there was no difference in chlorophyll content (SPAD value) between groups. The yield in G1 areas was 9~15% less than in G1 and G3. The decrease in yield in G2 areas could be due to lower panicle number, spikelet number, and ripening rate. In addition, the decrease in yield in G2 areas is likely because maximum, minimum, and average daily temperatures during the growing season were lower than those in G1 and G3. However, mineral nutrients in the soil were higher in the G2 area than in G1 and G3. The overall mineral content in plants tended to be higher in G1 areas than in G2 and G3. Mineral content such as Cu, K, Mg, and P in G3 areas and crude protein and most amino acids in G2 areas tended to be relatively low compared to other areas. Thus, the G1 area may be suitable for barley cultivation without adverse impacts on barley yield, main constituents, amino acids, and mineral contents compared to the main producing areas in G3.

• Korea Science and Art Forum
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• v.29
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• pp.305-318
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• 2017

The need for recognizing the crime in the urban spaces as a social problem and finding out specific approaches such as the study of space design and various guidelines for crime prevention is increasing. In this regard, "Crime Prevention Through Environmental Design" (marked as "CPTED") is actively underway. Yeomri-dong Salt Way is the first place to which the Seoul Crime Prevention Design Project was appled. The business objective of improving the local environment has been implemented rationally through cooperation and voluntary participation between subject of the project executives and community members. Since its efficiency has been proven, the sites have been expanded since then and becomes a benchmarking example of each local government.This kind of problem solving effort has the same context in purpose and direction of the 'Village Art Project' which has been implemented since 2009 with the aim of promoting the culture of the underdeveloped area and encouraging the participation of the residents by introducing the public art. It is noteworthy that this trend is centered around the characteristics of community functions and values. The purpose of this study is to propose the application method of community furniture as a way to increase the efficiency of CPTED to improve the 'quality of life' of residents. To do this, we reviewed CPTED, community design, public art literature and prior research, and identified the problems and implications based on the site visit Yeomri-dong of Seoul and Gamcheon Village of Pusan which is the successful model of "Seoul Root out Crime by Design" and 'Maeulmisul Art Project' respectively. The common elements of the two case places identified in this study are as follows: First, the 'lives' of community residents found its place in the center through the activation of community by collaborative activities in addition to the physical composition of the environment. Second, community design and introduction of public art created a new space, and thereby many people came to visit the village and revitalize the local economy. Third, it strengthened the natural monitoring, the territoriality and control, and the activity increase among the CPTED factors. The psychological aspect of CPTED and the emotional function of public art are fused with the 'community furniture', thereby avoiding a vague or tremendous approach to the public space through a specific local context based on the way of thinking and emotion of local people and it will be possible to create an environment beneficial for all. In this way, the possibility and implication of the fusion of CPTED and public art are expected to be able to reduce the social cost through the construction of the crime prevention infrastructure such as expansion of the CPTED application space, and to suggest a plan to implement the visual amenity as a design strategy to regenerate city.

• Economic and Environmental Geology
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• v.56 no.3
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• pp.311-330
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• 2023

Development of Carbon Capture and Storage (CCS) technique is becoming increasingly important as a method to mitigate the strengthening effects of global warming, generated from the unprecedented increase in released anthropogenic CO₂. In the recent years, the characteristics of basaltic rocks (i.e., large volume, high reactivity and surplus of cation components) have been recognized to be potentially favorable in facilitation of CCS; based on this, research on utilization of basaltic formations for underground CO₂ storage is currently ongoing in various fields. This study investigated the feasibility of underground storage of CO₂ in basalt, based on the examination of the CO₂ storage mechanisms in subsurface, assessment of basalt characteristics, and review of the global research on basaltic CO₂ storage. The global research examined were classified into experimental/modeling/field demonstration, based on the methods utilized. Experimental conditions used in research demonstrated temperatures ranging from 20 to 250 ℃, pressure ranging from 0.1 to 30 MPa, and the rock-fluid reaction time ranging from several hours to four years. Modeling research on basalt involved construction of models similar to the potential storage sites, with examination of changes in fluid dynamics and geochemical factors before and after CO₂-fluid injection. The investigation demonstrated that basalt has large potential for CO₂ storage, along with capacity for rapid mineralization reactions; these factors lessens the environmental constraints (i.e., temperature, pressure, and geological structures) generally required for CO₂ storage. The success of major field demonstration projects, the CarbFix project and the Wallula project, indicate that basalt is promising geological formation to facilitate CCS. However, usage of basalt as storage formation requires additional conditions which must be carefully considered - mineralization mechanism can vary significantly depending on factors such as the basalt composition and injection zone properties: for instance, precipitation of carbonate and silicate minerals can reduce the injectivity into the formation. In addition, there is a risk of polluting the subsurface environment due to the combination of pressure increase and induced rock-CO₂-fluid reactions upon injection. As dissolution of CO₂ into fluids is required prior to injection, monitoring techniques different from conventional methods are needed. Hence, in order to facilitate efficient and stable underground storage of CO₂ in basalt, it is necessary to select a suitable storage formation, accumulate various database of the field, and conduct systematic research utilizing experiments/modeling/field studies to develop comprehensive understanding of the potential storage site.

• Economic and Environmental Geology
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• v.56 no.3
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• pp.239-257
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• 2023

Sangdong deposit, a W-Mo skarn deposit, is located in Taebaeksan mineralized district, hosting vertically developed scheelite-quartz veins that formed at the late ore-forming stage. In this study, we tried to examine the geochemical signatures of ore-forming fluids and vein-forming mechanisms by analyzing the micro-texture of quartz veins and trace element concentrations of quartz. As a result of texture analyses, quartz veins in the hanging wall orebody and the foot wall orebody commonly exhibit the blocky and the elongate blocky texture, respectively, whereas quartz veins in the main orebody show both textures. These textural differences indicate that quartz veins from the hanging wall orebody were precipitated by the primary hydrofracturing due to H₂O saturation in the igneous body with relatively high temperature and pressure at a vein-skarn stage, and after that, repeated hydrofracturing caused the formation of quartz veins from the main orebody and foot wall orebody. The results of trace element concentrations show that Li⁺+Al³⁺↔Si⁴⁺ is a main substitution mechanism. However, those of the foot wall orebody were clearly divided into a Li⁺-dominated substitution and a Na⁺-, K⁺-dominated substitution. Considering that quartz veins from the foot wall orebody commonly show the elongate blocky texture, such a distinction means that it is a result of repeated injections of fluid with the different composition. Ti concentrations of quartz from the hanging wall, main, and the foot wall orebody are 28.6, 8.2, and 15.7 ppm in average, respectively. Given a proportional relationship between the precipitation temperature and Ti concentrations, it seems that quartz veins from the hanging wall orebody were precipitated at the highest temperature. Al concentrations of the hanging wall, main, and the foot wall orebody having an inverse relationship with fluid pH are 162.3, 114.2, and 182.5 ppm in average, respectively. These results show that Al concentrations in vein-forming fluids were not changed dramatically. Moreover, these concentrations are extremely low in comparison with the other hydrothermal deposits. This indicates that quartz in overall ore veins at Sangdong deposit was precipitated from the constant condition with slightly acidic to near neutral pH.

• Conservation Science in Museum
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• v.3
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• pp.43-50
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• 2001

This article is about a joint project carried out by the National Museum of Korea and the Tokyo Cultural Properties Research Institute for the conservation of central Asia Wall painting that has been selected for the exhibition at the new Seoul National Museum of Korea at Yongsan. The investigation of the wall painting revealed very useful information. This includes the condition of the object, and the identification of evident damage, such as cracks, loss of pigment, plus materials and methods employed during the object's creation, as well as previous conservation treatment. The object was mainly made by applying plaster to the body (wall) that consisted of a mixture of soils and rice straws. Then, on the surface of the wall-painting, pigments were used to draw and to colour it. As a part of the investigation, radiocarbon dating was conducted using straw samples taken from the object. The result indicates that the object is probably dated form between the end of the 10th Century and the beginning of the 13th Century. The result of X-ray diffraction also revealed the composition of the pigments used on the surface. These are 1. gypsom [Ca(SO₄)·2H₂O], CaSO₄ and Calcite (CaCO₃) and Calcite (CaCO₃) that were used for the white background. 2. Pb₃O₄ and led Arsenate [Pb(As₂O₆) that were used for the red colouring. 3. Cuprite (Cu₂O), Arsenolite (As₂O₃) and Arsenic Oxide (As₂O₄) that were used for the green colouring.