• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.767-773
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• 2001

We investigated the impacts of the fairy-ring of Tricholoma matsutake on the dynamics of soil microflora and soil enzyme activities by grouping the soils around the fairy-ring of T. matsutake into four regions. The regions were grouped as 'zone of decayed mycorrhizae', 'zone of mycorrhizae for fruiting', 'zone of physiologically active mycorrhizae' and 'zone free from mycorrhizal infection'. Soil fungi and actinomycetes were quite little at the soils around the fairy-ring of T. matsutake compared to those of general forest soils, and there were significant differences among the four regions. The soils with the mycelial cluster of T. matsutake showed about one third of microbial population compared to those in the zone free from mycorrhizal infection, which indicated that T. matsutake took a dominant position within the fairy-ring of the fungus. We could manifest that T. matsutake showed a distinctive characteristics of mycorrhizal fungus since the activities of dehydrogenase were significantly different between the zone of physiologically active mycorrhizae and the zone free from mycorrhizal infection. The dehydrogenase activity was the highest at the early season of fruiting around the fairy-ring of T. matsutake, while the acid-phosphatase activity increased from March to June followed by a slight decrease on August and peaked on October. This phenomenon made us infer that the vitality of T. matsutake be sustained after fruiting.

• Korean Journal of Remote Sensing
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• v.19 no.4
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• pp.307-317
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• 2003

This paper presents an algorithm that automatically extracts buildings among many different features on the earth surface by fusing LIDAR data with panchromatic aerial images. The proposed algorithm consists of three stages such as point level process, polygon level process, parameter space level process. At the first stage, we eliminate gross errors and apply a local maxima filter to detect building candidate points from the raw laser scanning data. After then, a grouping procedure is performed for segmenting raw LIDAR data and the segmented LIDAR data is polygonized by the encasing polygon algorithm developed in the research. At the second stage, we eliminate non-building polygons using several constraints such as area and circularity. At the last stage, all the polygons generated at the second stage are projected onto the aerial stereo images through collinearity condition equations. Finally, we fuse the projected encasing polygons with edges detected by image processing for refining the building segments. The experimental results showed that the RMSEs of building corners in X, Y and Z were 8.1cm, 24.7cm, 35.9cm, respectively.

• Korean Journal of Plant Taxonomy
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• v.35 no.1
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• pp.7-23
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• 2005

Molecular phylogenetic studies were conducted to evaluate interspecific relationships in 40 populations of Viola including 35 Korean taxa, four Japanese populations and one outgroup using nuclear ribosomal ITS sequences. The phylogenetic analyses were conducted using parsimony and neighbor-joining methods. Subsection Trigonocarpae of section Nomimium appeared as the most basal clade within the Korean Viola. Section Dischidium and Chamaemelanium was monophyletidbootstrap 100%) and placed between subsect. Trigonocarpae and three other subsections of sect. Nomimium. Sect. Nomimium was paraphyletic. Although each subsectional grouping was in accordance with previous infrageneric classification based on morphological characters, yet discordance remained at the series level. Two evolutionary trends observed in the ITS tree were as follows. First, subsect. Trigonocarpae(x=10) was derived from the outgroup(x=6); Second, subsects. Bilobatae and Vaginatae(x=10 or 12), and subsect. Patellares(x=12) of sect. Nomimium were originated from sects. Dischidium and Chamaemelanium(x=6). Viola albida complex including three very closely related taxa was recognized as independent group within subsect. Patellares in parsimony tree. This result suggested that they should be treated as a taxa in series Pinnatae. Phylogenetic position of a putative hybrid species, Viola woosanensis was not supported with previous morphological hypothesis.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.944-958
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• 2011

Soil hydraulic properties such as hydraulic conductivity or water retention which are costly to measure can be indirectly generated by soil pedotransfer function (PTF) using easily obtainable soil data. The field soil structure description which is routinely recorded could also be used in PTF as an input to reduce the uncertainty. The purposes of this study were to use qualitative morphological soil structure descriptions and soil structural index into PTF and to evaluate their contribution in the prediction of soil hydraulic properties. We transformed categorical morphological descriptions of soil structure into quantitative values using categorical principal component analysis (CATPCA). This approach was tested with a large data set from the US National Pedon Characterization database with the aid of a categorical regression tree analysis. Six different PTFs were used to predict the saturated hydraulic conductivity and those results were averaged to quantify the uncertainty. Quantified morphological description was successively used in multiple linear regression approach to predict the averaged ensemble saturated conductivity. The selected stepwise regression model with only the transformed morphological variables and structural index as predictors predicted the $K_{sat}$ with $r^2$ = 0.48 (p = 0.018), indicating the feasibility of CATPCA approach. In a regression tree analysis, soil structure index and soil texture turned out to be important factors in the prediction of the hydraulic properties. Among structural descriptions size class turned out to be an important grouping parameter in the regression tree. Bulk density, clay content, W33 and structural index explained clusters selected by a two step clustering technique, implying the morphologically described soil structural features are closely related to soil physical as well as hydraulic properties. Although this study provided relatively new method which related soil structure description to soil structure index, the same approach should be tested using a datasets containing the actual measurement of hydraulic properties. More insight on the predictive power of soil structure index to estimate hydraulic properties would be achieved by considering measured the saturated hydraulic conductivity and the soil water retention.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1169-1175
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• 2011

The soil chemical properties, microbial community structures and biochemical properties of lettuce or cucumber-cultivated greenhouse soil samples were analyzed to assess soil health and characterize microbial distribution in 8 locations in Korea. Although most of chemical properties were within the soil management guidelines, the available phosphate, and the contents of exchangeable potassium and calcium were higher than those of recommended levels. In the culture-dependent analysis, 841 bacterial strains were isolated from the greenhouse soils and were identified at the genus level by 16S rRNA gene sequences analysis. The dominant bacterial genera were Bacillus (35.7%), Microbacterium (9.3%), Arthrobacter (5.7%) and Lysobacter (5.1%). The abundance of pseudomonads was highly variable depending on the soil samples. In the culture-independent analysis, soil microbial community was investigated by using phospholipid fatty acid (PLFA) method. Principal component analysis (PCA) showed that a specific grouping for microbial community structure in the greenhouse soils was not observed based on cultivated crops and investigated sites. The results revealed that the greenhouses soils examined are relatively sound managed in terms of soil chemical contents and microbial properties.

• International Journal of High-Rise Buildings
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• v.10 no.4
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• pp.345-364
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• 2021

Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (V_S / V_BO), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.65-70
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• 2019

The purpose of this study is to understand the college students' needs for software curriculum which based on surveys from educational satisfaction of the software lecture evaluation, as well as to find out the improvement plan by applying the text content analysis method. The research method used the text content analysis program to calculate the frequency of words occurrence, key words selection, co-occurrence frequency of key words, and analyzed the text center and network analysis by using the network analysis program. As a result of this research, the decent points of the software education network are mentioned with 'lecturer' is the most frequently occurrence after then with 'kindness', 'student', 'explanation', 'coding'. The network analysis of the shortage points has been the most mention of 'lecture', 'wish to', 'student', 'lecturer', 'assignment', 'coding', 'difficult', and 'announcement' which are mentioned together. The comprehensive network analysis of both good and shortage points has compared among key words, we can figure out difference among the key words: for example, 'group activity or task', 'assignment', 'difficulty on level of lecture', and 'thinking about lecturer'. Also, from this difference, we can provide that the lack of proper role of individual staff at group activities, difficult and excessive tasks, awareness of the difficulty and necessity of software education, lack of instructor's teaching method and feedback. Therefore, it is necessary to examine not only how the grouping of software education (activities) and giving assignments (or tasks), but also how carried out group activities and tasks and monitored about the contents of lectures, teaching methods, the ratio of practice and design thinking.

• Economic and Environmental Geology
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• v.51 no.6
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• pp.543-551
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• 2018

The uranium concentrations were determined in groundwater collected from 3,820 community groundwater system (CGS) located in remote rural areas where access to the nationwide water work is not easy. The frequency distribution of uranium concentrations shows a lognormal distribution which is common in most radionuclide surveys. The measured maximum uranium concentration was $1,757.0{\mu}g/L$ with an average of $6.46{\mu}g/L$ and a median of $0.76{\mu}g/L$. When grouping the uranium concentration results of CGS into 10 geological units, the median uranium concentration was high ($0.99-2.05{\mu}g/L$) in three granite areas, and low in sedimentary rocks areas and porous volcanic rocks areas ($0.04-0.50{\mu}g/L$). Of the 3,820 samples, 3.8% are above the guideline value of $30{\mu}g/L$ (WHO, 2011). On the other hand, the exceeding rates of JGRA and PGRA CGS are 8.5% and 7.5%, respectively. Therefore, attention should be paid for the development of new CGS along with the management of the existing CGS in JGRA and PGRA areas.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.3
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• pp.279-298
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• 2019

This study comprehensively addresses recent progress at KAERI in waste treatment technology to cope with waste produced by pyroprocessing, which is used to effectively manage spent fuel. The goal of pyroprocessing waste treatment is to reduce final waste volume, fabricate durable waste forms suitable for disposal, and ensure safe packaging and storage. KAERI employs grouping of fission products recovered from process streams and immobilizes them in separate waste forms, resulting in product recycling and waste volume minimization. Novel aspects of KAERI approach include high temperature treatment of spent oxide fuel for the fabrication of feed materials for the oxide reduction process, and fission product concentration or separation from LiCl or LiCl-KCl salt streams for salt recycling and higher fission-product loading in the final waste form. Based on laboratory-scale tests, an engineering-scale process test is in progress to obtain information on the performance of scale-up processes at KAERI.

• Journal of the Korean Society for Library and Information Science
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• v.53 no.2
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• pp.91-116
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• 2019

This study conducted a demand analysis for the operation and management of closed schools, the direction of future use of closed schools, and the utilization of closed schools, among local residents expected to play a key role in the successful use of closed libraries. According to the study, residents in areas where schools actually occur may actively consider the use of closed schools when they are lacking in the number of libraries in the region or when they hope to remodel their schools as libraries, given that they are positive about future use of closed schools and that remodeling them is more economical in terms of cost than building new libraries. The current awareness of the use and operation of closed schools remains at a normal level, so it is deemed necessary to improve the direction of the promotion, operation and recycling of closed schools in the order of promotion, operation and physical aspects by grouping obstacles to the operation and management of closed schools. In addition, the current status of cultural facilities and the demands of local residents are met in terms of the types of use of closed school facilities, and it means that closed schools can be used in a relatively easy-to-access location based on their location, while libraries can be used as a space for cultural facilities that are different from the existing public libraries, exhibition halls, and eco-friendly libraries.