• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.233-245
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• 2014

Nighttime correction of $CO_2$ flux is one of the most important and challenging tasks in eddy covariance measurements over a complex mountainous terrain. In this study, we have scrutinized the quality and the credibility of the $CO_2$ flux datasets which were produced by employing three different methods of nighttime correction, i.e., (1) friction velocity ($u^*$) correction, (2) light response curve (LRC) correction, and (3) advection-based van Gorsel (VG) correction. The whole year datasets used in our analysis were collected at the two KoFlux tower sites (i.e., GDK deciduous forest site at the upper hill and GCK coniferous forest site at the lower hill) located in the valley of Gwangneung National Arboretum in central Korea. The resultant magnitudes and patterns of ecosystem respiration ($R_E$), gross primary productivity (GPP), and net ecosystem exchange (NEE) of $CO_2$ showed marked differences among the datasets produced with three different correction methods, which were also site-specific. The examination from micrometeorological and ecological perspectives suggests that the major cause of some inconsistency seems to be associated with the advection of $CO_2$ along the sloping terrain and the inappropriate selection of the correction data that might have been already affected by advective flows. The comparison with the results from other studies indicated that the overall characteristics of the corrected $CO_2$ fluxes at GDK and GCK (except those with LRC correction) were well within the ranges reported in the literature for various ecosystems in East Asia in similar latitudes. However, our study also implies that there will be always a room for further improvement in the present datasets. Therefore, caution must be exercised for the data users in order to properly use the updated version of datasets through transparent, open and participatory communication with data producers.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.366-377
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• 2016

Water use efficiency (WUE) is considered as an important ecological indicator which may provide information on the process-structure relationships associated with energy-matter-information flows in ecosystem. The WUE at ecosystem-level can be defined as the ratio of gross primary productivity (GPP) to evapotranspiration (ET). In this study, KoFlux's long-term (2007-2015) eddy covariance measurements of $CO_2$ and water vapor fluxes were used to examine the WUE of needle fir plantation in Korea National Arboretum. Our objective is to ascertain the seasonality and inter-annual variability in WUE of this needle fir plantation so that the results may be assimilated into the development of a holistic ecological indicator for resilience assessment. Our results show that the WUE of needle fir plantation is characterized by a concave seasonal pattern with a minimum ($1.8-3.3g\;C{\cdot}(kg\;H_2O)^{-1}$) in August and a maximum ($5.1-11.4g\;C{\cdot}(kg\;H_2O)^{-1}$) in February. During the growing season (April to October), WUE was on average $3.5{\pm}0.3g\;C\;(kg\;H_2O)^{-1}$. During the dormant seasons (November to March), WUE showed more variations with a mean of $7.4{\pm}1.0g\;C{\cdot}(kg\;H_2O)^{-1}$. These values are in the upper ranges of WUE reported in the literature for coniferous forests in temperate zone. Although the growing season was defined as the period from April to October, the actual length of the growing season (GSL) varied each year and its variation explained 62% of the inter-annual variability of the growing season WUE. This is the first study to quantify long-term changes in ecosystem-level WUE in Korea and the results can be used to test models, remote-sensing algorithms and resilience of forest ecosystem.

• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.313-324
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• 2009

We explore the effect of particle shape and size on 3-dimensional (3D) network and pore structure of porous earth materials composed of glass beads and silica gel using NMR micro-imaging in order to gain better insights into relationship between structure and the corresponding hydrologic and seismological properties. The 3D micro-imaging data for the model porous networks show that the specific surface area, porosity, and permeability range from 2.5 to $9.6\;mm^2/mm^3$, from 0.21 to 0.38, and from 11.6 to 892.3 D (Darcy), respectively, which are typical values for unconsolidated sands. The relationships among specific surface area, porosity, and permeability of the porous media are relatively well explained with the Kozeny equation. Cube counting fractal dimension analysis shows that fractal dimension increases from ~2.5－2.6 to 3.0 with increasing specific surface area from 2.5 to $9.6\;mm^2/mm^3$, with the data also suggesting the effect of porosity. Specific surface area, porosity, permeability, and cube counting fractal dimension for the natural mongolian sandstone are $0.33\;mm^2/mm^3$, 0.017, 30.9 mD, and 1.59, respectively. The current results highlight that NMR micro-imaging, together with detailed statistical analyses can be useful to characterize 3D pore structures of various porous earth materials and be potentially effective in accounting for transport properties and seismic wave velocity and attenuation of diverse porous media in earth crust and interiors.

• Journal of Korean Home Economics Education Association
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• v.18 no.2 s.40
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• pp.63-77
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• 2006

The Purpose of this study is to provide the basic data for the improvement or the contents or clothing curriculum in the 7th technology home economics of middle school. The standard of satisfaction of students' according to the detail domains and the standard of necessity and practical use and learners' patterns of activity task suggested in textbooks were evaluated. The ninth grade 169 boy students and 336 girl students in the national capital region were participated in this survey. According to the survey results, firstly, a dress domain got the highest relative importance(28.56%) while a clothes material domain took the lowest relative importance(8.07%) among various detail domains. Secondly, the standard of satisfaction according to each detail domain fell below the average. Generally girls' satisfaction for teaching was higher than boys'. Thirdly, a clothes material domain showed the lowest necessity for textbook contents according to detail domain and other domains showed above the average. The necessity for textbook contents appeared high for boy students rather than girl students. In addition, boy and girl students did not have interest in content relevance in textbook. Especially, they could not do well and understand experiments and practices in clothing section. Finally, The degree of utilization of the activity task ill textbooks was very low. Among various activity tasks, the learning by discovering and exploring were more utilized than cooperating learning.

• Journal of Korean Home Economics Education Association
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• v.20 no.1
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• pp.63-83
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• 2008

The purpose of this study was to investigate food involvement, dietary behavior and relationship according to the levels of nutrition knowledge. Data in this research was obtained by using the questionnaire which was given out to 528 subjects(boys 182, girls 346) in Naju city area. The awareness of dietary behavior of middle school students put the first priority on breakfast from among 3 meals a day, and they selected 'taste' as the most important criterion. The majority and above of subjects responded that they had ever delivered food at least more than 1 or 2 times a week. This research found that middle school students are tends to regard themselves as being rather close to obesity or fatness. Subjects were also aware that they have some problems with a unbalanced eating habbit and irregular timing of having meals, and more than 40% of the subjects responded that they obtain the most of information about food & dietary behavior through television. Significant difference was found in the food involvement with related variables such as sex, grade, the academic background of mother, self-perception of weight, the way of weight control, perception of problems requiring improvement. Dietary behavior related with variables showed significant difference. Variables are grade, perception of meal importance, selecting standard of food, method of weight control, improvement of eating habits. Dietary behavior is found highly relative with food involvement. Dietary behavior is found highly relative with food involvement. In conclusion, suggestions that could bring motivation to improvement is more essential to the nutrition education rather than knowledge oriented education.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.784-789
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• 2005

The inhibitory effects of hot water extracts of Rhus verniciflua Stokes pith and peel roasted at 170, 200 and $220^{\circ}C$ on lipid peroxidation, formation of DPPH free radicals and growth of four human cancer cells such as HepG2 (liver cancer), SNU-1 (stomach cancer), MCF-7 (breast cancer) and Widr (colon cancer) were examined. The antioxidant activities and growth inhibitory effects on cancer cells of hot water extracts of peel were higher than those of pith, and the activities were dose-dependent. The roasting temperature showing the highest antioxidant activities and growth inhibitory effects on cancer cells was in the range of $170\~200^{\circ}C$ The lipid peroxidation and formation of DPPH free radicals of hot water extracts of roasted pith and peel were inhibited to 50.9, $56.5\%\;and\;79.0,\;78.4\%$ at the concentration of $500\mu g/mL$, respectively. The growth inhibitory effects of roasted pith and peel on cancer cells were in the order of Widr (41.5, $36.0\%$) > HepG2 (61.5, $44.0\%$) > MCF-7 (92.0, $69.2\%$)> SNU-1 (100, $100\%$) cells at the concentration of $1,000\mu g/mL$ as compared with the control, respectively. These results suggest that roasted Rhus verniciflua Stokes could be an useful natural medicinal plant for colon cancer.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.478-484
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• 2012

This study was carried out to investigate the plant growth and ion absorbance balance of various native plants affected by the NaCl concentration (0, 100, 200, 300 mM). Carex blepharicarpa, Carex lenta, Carex matsumarae, Carex sendaica, Iris pseudacorus L., Sedum oryzifolium Makino, Sedum polytrichoides Hemsl., and Typha angustifolia L. were used in this experiment. Carex blepharicarpa, Carex lenta, Carex matsumarae, and Iris pseudacorus L. were tolerant of salinity at the NaCl concentration of 200 mM. The root growth of Carex sendaica and Typha angustifolia L. was suppressed at the NaCl concentration of 100 mM, expecially the root growth responded more sensitively than the upper growth to salinity. The K absorbance of Carex sendaica decreased according to the NaCl application, and the Na/K rate value was 3 at the NaCl concentration of 300 mM. The K, Ca, and Mg absorbance of Typha angustifolia L. decreased at the NaCl concentration of 200~300 mM, and the Na/K rate value was 0.8 at the NaCl concentration of 300 mM. The plant growth of Sedum oryzifolium Makino and Sedum polytrichoides Hemsl. was suppressed at the NaCl concentration of 100~200 mM. The K, Ca, and Mg absorbance of Sedum oryzifolium Makino decreased at the NaCl concentration of 200~300 mM, and Sedum polytrichoides Hemsl. was unaffected by the NaCl application. The Na/K value was 1 in both plants. Therefore, Carex blepharicarpa, Carex lenta, Carex matsumarae, and Iris pseudacorus L. were tolerant plants of salinity at the NaCl concentration of 200 mM considering the plant growth and ion absorbance balance. Especially, the Carex plants were expected to expanding use by the proven tolerance of salinity. The root growth of Carex sendaica, Sedum oryzifolium Makino, Sedum polytrichoides Hemsl., and Typha angustifolia L., was suppressed at the NaCl concentration of 100 mM, but there was no distinct tendency of ion absorbance in leaves according to the NaCl application.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1470-1475
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• 1998

Two kinds of Korean rice-wine (Yakju) with different process and ingredients, and Japanese rice-wine (Sake) were chosen for this study, and throughly dried and solubilized in water or cell culture medium. In vitro cytotoxicity assays of the solubilized wine solids exhibited that maximum dilution factors for inhibition of B 16BL6 mouse melanoma cell growth were 16X for herbal medicine-added rice-wine (Korean rice-wine I) and typical Korean rice-wine (Korean rice-wine II), and 8X for Japanese rice-wine. Their cytotoxic effects on HRT18 human colon adenocarcinoma cells were even lower than those on B16BL6 cells. The morphology of the tumor cells were changed by addition of the solubilized wine solids. Inhibitory effect of the rice-wine on in vivo tumor growth and metastasis were monitored after implantation of B16BL6 cells into C57BL/6 mice with daily feeding the solubilized wine solids. Compared to non-fed control groups, B16BL6 tumor growth and metastasis to lung were clearly inhibited by feeding the wine solids, in order of Korean rice-wine I > Korean rice-wine II > Japanese rice-wine. The data of in vitro cytotoxicity and the cell shape changes indicate that the inhibitory effect of tumor progression may be attributed to tumor cell differentiation or immune stimulation induced by certain components in the rice-wine, rather than direct cytotoxicity of the components.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.1
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• pp.23-33
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• 2012

In this study, how much users of Hannamkeumbuk Keumbuk Mountains are aware of Baekdaegan and its attached mountain chains, a traditional geographic system, according to Sangyungpyo and basic data like the degree of awareness and use-behaviors, etc. have been studied. In addition, the environmental value of Hannamkeumbuk Keumbuk Mountains separating the central and the southern part of Korea among attached mountain ranges, secondary mountain chains, which act as an ecosystem buffer in the Baekdudaegan Range, has been estimated at the current amount of currency. In the questions of the perception of the traditional classification standard of mountain chains and Baekdudaegan, more than 70% of respondents answered that they had heard of or known them but 66.8% werenot aware of Hannamkeumbuk Keumbuk Mountains. While the awareness for Baekdudaegan is high, the perception of its attached mountain chains was very poor. DBDC responder system and CVM, which is used widely for the value estimate method of environment goods, were used. As the result, an additional benefit got when a person visits Hannamkeumbuk Keumbuk mountains was estimated as 5,813 won. It could find out that this amount was very low compared with 51,984 won, average visit cost. It judged that the reason was that damage of environmental conditions, the monotony of the trails and progress of indiscriminate environmental destruction, etc. The results of this study will offer a new perspective on public relations activities and resource conservation of Baekdudaegan and its attached mountain chains and estimate perceptions and efficient services for visitors to HannamKeumbuk Keumbuk Mountains. This study will act as data for basic planning and management to increase the mountains' value and to preserve them. Further studies are needed to make a frame of work division and management with various organizations so that the management of Hannamkeumbuk-Keumbuk Mountains may be properly established and their value may been hanced.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.3
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• pp.128-136
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• 2018

This study was centered on the protested data of the issue of "History of Landscape Architecture" in the handwritten course of landscaping articles of National Qualifications Test. The purpose of this study is to examine the types of social problems in the process of correcting erroneous historical facts. The purpose of this study was to find alternatives for the development of the field of landscape and culture history that can assist in the verification of the historical facts of the landscape sciences examination questions. The main results are as follows. First, as a result of analyzing the contents of the landscape architects' subject matter, the establishment of concept of landscape style and form and the confirmation of historical facts were investigated as important types to be established for development of landscape landscape history department. It seems that the social consensus of the expert group is needed to supplement the lack of data to refer to landscape architectural theory. Second, the analysis of the problematic narrative contents resulted in a total of five types of questionnaires. The appeared in the Undefined style and form(52.94%), Unproven historical facts(25.13%), Obscurity Era classification(11.77%), Lack of specificity(6.95%), Content scope of obscurity events(3.21%) Third, it is not only the lack of information to learn the theory by comparing and analyzing the contents of the statements in the landscape architect 's question items, but also the difference of contents between books was analyzed as the main cause of the problem. As a result of examining the characteristics and examples of the issues raised in landscape architectural problems, it was related to the social phenomenon, and it was classified into cultural factors and political factors. Fourth, the resolution of problematic issues in landscape architects' landscaping articles, which are national technical qualification tests, shows positive results. The information determined in the process of solving the perceived content can be used directly in landscaping field, and it helps the accuracy of the verification process by identifying the types and characteristics of the issues.