• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.215-234
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• 2014

The purpose of this study is to identify the type and characteristics of the domestic natural streams in order to establish a basis for stream restoration and evaluation. To this end, 95 domestic natural stream areas, which have various natural environments, were selected except for the province of island and then the characteristics of natural environment, hydromorpholoy, plant and vegetation were investigated and analyzed in each stream area. As a result, 95 stream areas were classified into total 24 types according to 3 criteria such as stream size (4 types), altitude (3 types), bed material (5 types). Depending on altitude class that is the environmental factor showing the highest correlation with each stream types, the emergence of vegetation and plant, 24 stream types were reclassified into 3 types such as lowland (altitude less than 200m), mountain (altitude from 200m to 500m), highland (altitude more than 500m), and hydromorpholoy, plant and vegetation characteristics of each stream type were compared. First, when compared to the mountain and highland streams, the typical features of lowland streams were as follows: Stream size was large but bed material size was small and there were many valley forms where flood plane were developed well. In addition, the more large stream size was, the more cross-section width variability, bars and sinuosity were in good conditions. In lowland stream, representative vegetation community was Salix koreensis community. On the other hand, when compared to the lowland streams, the typical features of mountain and highland streams were as follows: Stream size was small but bed material was coarse-grained and its size was large. Mountain and highland streams valley form where flood plane was not developed well was narrow, and sinuosity and bars development were weak. Representative vegetation communities of mountain streams were Quercus serrata -, Quercus variabilis -, Styrax japonica community and representative vegetation communities of highland streams were Pinus densiflora -, Quercus mongolica -, Fraxinus rhynchophylla community.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.246-254
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• 2013

Five isolates of Tomato yellow leaf curl virus (TYLCV) collected from various regions of Korea were amplified using PCR and determined the sequences of full-length genome, respectively. The PCR-amplified DNA of each TYLCV isolate was introduced into a binary vector to construct infectious clone containing 1.9 copies of the corresponding viral genome. Various cultivars and breeding lines of tomato were inoculated with Agrobacterium tumefaciens harboring infectious clone of each TYLCV isolate to assess resistance against TYLCV. Susceptible cultivar 'Super-sunread' revealed typical yellowing and narrowing of the upper leaves. In contrast, breeding linesTY12, GC9, GC171, and GC173, which contained the TY-1 and/or TY-3 genes that confer resistance against TYLCV in nature, were completely symptomless, suggesting that the lines were resistant to challenging TYLCV isolates. Symptoms of TYLCV in susceptible tomato cultivars are significantly different from those of TYLCV in the resistant tomato cultivars at 30 days after agroinfiltration. Although genomic DNAs of TYLCV were detected from the breeding lines TY12, GC9, GC171, and GC173 using real-time PCR analysis with specific primers, levels of TYLCV DNA accumulation in the resistant breeding lines were much lower than those of TYLCV DNA accumulation in susceptible tomato cultivars. Similar symptom severity and levels of TYLCV DNA accumulation were observed from TYLCV infections mediated by Bemisia tabaci in the resistant and susceptible tomato cultivars. Concentration of agrobacterium did not affect the response of tomato cultivars against TYLCV inoculation. Taken together, these results suggest that TYLCV inoculation via agroinfiltration is as effective as inoculation through Bemisia tabaci and is useful for breeding programs of TYLCV-resistant tomato.

• Journal of the Korean Society of Radiology
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• v.14 no.6
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• pp.841-848
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• 2020

In the field of radiation therapy using photon beams and electron beams, since each patient has a different sensitivity to radiation, skin side effects may occur even at the same dose. Therefore, if there is a risk of excessive dose to the skin, a dosimeter is attached to verify whether the correct dose is being investigated. However, since the skin dosimeter checks the attachment site visually by measuring a point dose, it is difficult to confirm an accurate dose distribution. As a result, the measurement and simulation errors of the material HgI₂ in the 6 MV photon beam were 3.73% and 5.24%, respectively, at the minimum thickness of 25 ㎛, and the material PbI₂ was 4.73% and 5.65%, respectively. On the other hand, as a result of the 6 MeV electron beam, the measurement and simulation errors of the material HgI₂ were 1.35% and 1.12%, respectively, at a minimum thickness of 25 ㎛, and the material PbI₂ showed relatively low attenuation error, 1.67% and 1.20%, respectively. Therefore, it was evaluated that the thickness of the photon beam within 25 ㎛ and the electron beam within 100 ㎛ is suitable to have a reduction rate error within 5%. This study presents a new research direction for a flexible dosimeter attached to the human body that is required in clinical practice and the construction conditions of a future skin dosimeter.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.620-637
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• 2008

$Che{\breve{o}}n$ (提堰) refers to the irrigation facilities used to provide water to the land on which rice is farmed. As the maintenance of $Che{\breve{o}}n$ required great amounts of capital, labor, and technology, the construction and maintenance of such facilities was controlled by the government. $Che{\breve{o}}n$ was perceived as being of particular importance during the $Che{\breve{o}}n$ era, which adopted agriculture as the basis of state management. Therefore, the management of $Che{\breve{o}}n$ was considered to be one of the main state policies. This is why $Che{\breve{o}}n$-related records can often be found in the historical documents written during the $Che{\breve{o}}n$ era. As such historical documents in the form of Jiriji (地理誌, geographical descriptions) include detailed descriptions of the number, size, and location of $Che{\breve{o}}n$ in individual counties($kunby{\breve{o}}n$), these help to conduct comprehensive analysis of the state of $Che{\breve{o}}n$ during the $Che{\breve{o}}n$ era. Based on these facts, this study attempts to establish a database of the $Che{\breve{o}}n$-related contents included in the <$Y{\breve{o}}jitos{\breve{o}}$(與地圖書)> published during the latter period of $Che{\breve{o}}n$, and using the established database, to identify the regional characteristics of $Che{\breve{o}}n$. More precisely, by analyzing the state of the distribution of $Che{\breve{o}}n$ at the national level, an effort was made to review the regional characteristics of $Che{\breve{o}}n$ in terms of their distribution and of the natural geographical conditions found in the locales where $Che{\breve{o}}n$ were located, as well as of the interrelation between such $Che{\breve{o}}n$ and socioeconomic factors such as the scale of the population and the size of the area under cultivation. Other factors which were delved into included matters related to the size of $Che{\breve{o}}n$ such as their perimeter, length, and scale of the area which they irrigated, the characteristics of the locales where $Che{\breve{o}}n$ were located, and the regional differences in the characteristics of $Che{\breve{o}}n$.

• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.141-158
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• 2004

The dependency of criteria used to terminate compatibility tests on the prehydration and quality of bentonite in geosynthetic clay liners (GCLs) is evaluated based on permeation with chemical solutions containing 5, 10, 20, 50, and 100 mM calcium chloride ($CaCl_2$). The hydraulic conductivity tests are not terminated before chemical equilibrium between the effluent and the influent chemistry has been established, resulting in test durations ranging from < 1 day to > 900 days, with longer test durations associated with lower $CaCl_2$ concentrations. The evaluation includes both physical termination criteria (i.e., volumetric flow ratio and steady hydraulic conductivity based on ASTM D 5084, ${\ge}2$ pore volumes of flow, constant thickness of specimen) and chemical termination criteria requiring equilibrium between influent and effluent chemistry (viz., electrical conductivity, pH, and $Ca^{2+}\;and\;Cl^-$ concentrations). For specimens permeated with 5, 10, and 20 mM $CaCl_2$ solutions, only the criterion based on chemical equilibrium in $Ca^{2+}$ concentration correlates well with equilibrium in hydraulic conductivity, regardless of prehydration or quality of bentonite. However, all of the termination criteria, except for the volumetric flow ratio and 2 pore volumes of flow for the prehydrated specimens, correlate well with equilibrium in hydraulic conductivity regardless of prehydration or quality of bentonite when permeated with 50 and 100 mM $CaCl_2$ solutions. The results illustrate the uniqueness of the termination criterion based on solute concentration equilibrium between the effluent and the influent with respect to both prehydration and quality of bentonite in the GCLs.

• Journal of the Korean Geotechnical Society
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• v.36 no.2
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• pp.5-15
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• 2020

The liquefaction phenomenon that occurred during the Pohang earthquake (M_L=5.4) brought new awareness to the people about the risk of liquefaction caused by the earthquake. Liquefaction hazard maps with 2 km grid made in 2014 used more than 100,000 borehole data for the whole country, and regions without soil investigation data were produced using interpolation. In the mapping of macro liquefaction hazard for the whole country, the site amplification effect and the ground water level 0 m were considered. Recently, the Ministry of Public Administration and Security (2018) published a new site classification method and amplification coefficient of the common standard for seismic design. Therefore, it is necessary to rewrite the liquefaction hazard map reflecting the revised amplification coefficient. In this study, the results of site classification according to the average shear wave velocity in soils before and after revision were compared in the whole country. Also, liquefaction assessment results were compared in Gangseo-gu, Busan. At this time, two ground accelerations corresponding to the 500 and 1,000 years of return period and two ground water table, 5 m for the average condition and 0 m the extreme condition were applied. In the drawing of liquefaction hazard map, a 500 m grid was applied to secure a resolution higher than the previous 2 km grid. As a result, the ground conditions that were classified as S_C and S_D grounds based on the existing site classification standard were reclassified as S₂, S₃, and S₄ through the revised site classification standard. Also, the result of the Liquefaction assessments with a return period of 500 years and 1,000 years resulted in a relatively overestimation of the LPI applied with the ground amplification factor before revision. And the results of this study have a great influence on the liquefaction assessment, which is the basis of the creation of the regional liquefaction hazard map using the amplification factor.

• 대한공업교육학회지
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• v.38 no.2
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• pp.89-113
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• 2013

The study started from the point that learners should be basically equipped to quickly respond to changes in demand for future human resources efficiently and effectively, and an attitude to take part in learning voluntarily should thus be cultivated. To this end, the author applied the TAI model based on a module as a class strategy to solve problems related to several classes occurred in specialized high schools. This application of the TAI model was also motivated by the necessity for designing an appropriate teaching-learning method that encourages improvement of self-learning capacity, consistent learning motivation, and willingness rather than external factors. Through this work, the author aims to heighten the interest of learners and improve endurance in learning. The study results are as follows. First, the learning unit was structuralized as a module and then learning stages were proceeded with so that capacity to adapt to learning would improve. The achievement standard (learning goal) was structuralized in a module type by analyzing and reorganizing the textbook considering the link between the actual practice field and a curriculum based on subject characteristics. Through the process of module type learning stages, the student's capacity to ascertain characteristics of units and to adapt to learning both improved. Second, through application of a TAI model based on a module, Self-Directed Learning capacity and capacity to adapt to a new field improved. By applying the module, Self-Directed Learning could be accomplished more effectively than in the existing passive learning environment. By grafting cooperative learning of the TAI model, students had greater interest and achievement in classes, self-confidence and community consciousness, and an opportunity to broaden their thinking. In particular, improvement of self-confidence is effective in cultivating the capacity required in industrial society to transcend the learning of simple functions and knowledge, as well as the capacity to adapt to new environments. Third, by solving tasks focused on fields related to industrial sites, not only actual survey capacity but also additional capacity to identify and solve tasks through various experiences improved. Furthermore, it was helpful for students to have interest and motivation about their own life and learning to cultivate the qualities and capacity to adapt to the working world where new knowledge and technology rapidly change. Fourth, by applying a standard-based assessment system for technical subjects introduced in 2012 to model design for learning plans, clearer and more objective assessment criteria were arranged, and individual learning through instruction at each achievement level could be accomplished. This improved achievement level of individual learners was helpful in reaching achievement goals at specific levels by overcoming the disadvantages of cooperative learning in each group.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.172-179
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• 2017

The purpose of this study is to analyze the current original habitat and to conserve the narrow-mouthed toad populations. For this study, we used 240 pitfall traps (30 cm height ${\times}$ 20 cm width) to catch the narrow-mouthed toads that inhabit in Myeongji-dong, Gangseo-gu, in Busan metropolitan city from August 2, 2013 to November 7, 2013. We measured the environmental characteristics (soil composition factors, soil moisture, Humidity, soil temperature) for the seven habitat patterns of narrow-mouthed toads based on vegetation types. Main habitats of narrow mouthed toads were flat grassland where grass and false acacia grew and there was wetland all over the place. When analyzing habitats that main habitats of narrow-mouthed toads prefer after selecting representative seven vegetation, it was found that the most narrow-mouthed toads were caught in amur silver grass colony while the least narrow-mouthed toads were caught in bare land. Totally, we caught 846 narrow-mouthed toads over 68 times, and released them into the newly constructed habitat after injection VIE-tag. It seems that the reason for which the least narrow mouthed toads were caught in bare land is that bare land is not suitable for narrow mouthed toads to protect themselves from strong sunlight and to hide themselves from natural enemy. We found that temperature had the greatest influence on activities of narrow mouthed toads and at temperature of less than $15.6^{\circ}C$. We also found that the activities of narrow mouthed toads were remarkably low and then temperature was below $15.6^{\circ}C$. It meant that narrow mouthed toads seemed to go into hibernation. From this research, we could find the prefer habitat after analyzing habitats for the narrow-mouthed toads and could suggest for construction for the better habitat of narrow-mouthed toads.

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.169-177
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• 2014

BACKGROUND: The ferronickel and rapid cooling slags used in present study are industrial wastes derived from a steel factory in Korea. These slags are used as almost road construction materials after magnetic separation. However, the use of slag to remove phosphorus from wastewater is still a relatively less explored. The objective of this work was to evaluate the feasibility of ferronickel slag (FNS) and rapid cooling slag (RCS) as sorbents for phosphorus removal in wastewater. METHODS AND RESULTS: Adsorption experiments were conducted to determine the adsorption characteristics of the FNS and RCS for the phosphorus. Adsorption behaviour of the phosphorus by the FNS and RCS was evaluated using both the Freundlich and Langmuir adsorption isotherm equations. FNS and RCS were divided into two sizes as effective sizes. Effective sizes of FNS and RCS were 0.5 and 2.5 mm, respectively. The adsorption capacities (K) of the phosphorus by the FNS and RCS were in the order of RCS 0.5 (0.5105) > RCS 2.5 (0.3572) ${\gg}$ FNS 2.5 (0.0545) ${\fallingdotseq}$ FNS 0.5 (0.0400) based on Freundlich adsorption isotherm. The maximum adsorption capacities (a; mg/kg) of the phosphorus determined by the Langmuir isotherms were in the order of RCS 0.5 (3,582 mg/kg) > RCS 2.5 (2,983 mg/kg) > FNS 0.5 (320 mg/kg) ${\fallingdotseq}$ FNS 2.5 (187 mg/kg). RCS 0.5 represented the best sorbent for the adsorption of phosphorus. In the experiment, the Langmuir model showed better fit with our data than the Freundlich model. CONCLUSION: This study indicate that the use of RCS in constructed wetlands or filter beds is a promising solution for phosphorus removal via adsorption and precipitation mechanisms.

• Cartoon and Animation Studies
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• s.35
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• pp.29-65
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• 2014

Visual culture art education (VCAE) seems to be the new paradigm for art education after postmodernism. Getting beyond the traditional art education, VCAE has expanded its scope of interest to include the visual environment that surrounds our life, thus pushing the boundary of art education beyond the traditional fine arts to cover pop culture and visual art. VCAE shares the issues as well as a lot of elements of culture and art education and in fact serves as a major theoretic background for culture and art education, in that it pays attention to the sociocultural context of images and emphasizes visual literacy and constructionist learning. In this paper, I have reviewed the theoretical background and related issues of VCAE with a view to presenting a direction for animation education, which is gaining in importance coming into the Age of Digital Media. VCAE was born in the progressive cultural atmosphere from the 1970s and thereafter, and its gist consists in figuring out visual artifacts and their action in order to improve individual and social life. Yet, VCAE continues with its development according to the changing aspects of visual culture, and currently, it is expanding its scope of interest to cover the esthetic, experiential education in visual culture and construction of meaning through digital story-telling. In the visual environment of the Digital Age, animation is establishing itself as the center of the visual culture, being a form that goes beyond an art genre or technology to realize images throughout the visual culture. Also, VCAE, which has so far emphasized visual communication and critical reading of culture, would need to reflect the new aspects of the visual culture in digital animation across the entire gamut from experiencing to understanding and appreciating art education. In this paper, I emphasize on Cross-Curricula, social reconstruction, the expansion of animation education, interests in animation as a digital media, and animation literacy. A study of animation education from the perspective of VCAE will not only provide a theoretical basis for establishing animation education, but also enrich the content of VCAE, traditionally focused on critical text reading, and promote its contemporary and futuristic orientation.