• Korean Journal of Ecology and Environment
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• v.51 no.4
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• pp.331-344
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• 2018

Lotic organisms in streams are affected by natural and anthropogenic disturbances such as increase of heavy rainfall event caused by climate change and flow regime change caused by weir constructions. Based on domestic and foreign literature, 157 Korean benthic macroinvertebrate taxa were selected species as potential lotic candidates. Three shoreline sites (total 54 samples) were surveyed consecutively before ('08~'09), during ('10~'12) and after ('13~'16) the construction of the weirs (Gangcheon, Yeoju and Ipo weir) in the Namhan-River for tracing changes of lotic communities. As a result, water flow of the Ipo-wier and water quality variables such as T-N, T-P, BOD5, etc. of the weir section revealed no significant changes. Physical habitat conditions such as the flow velocity and streambed substrate evidently changed. Particulary, flow velocity measured at sampling points along with each microhabitat drastically decreased and particle size of streambed substrate steadily decreased after weir constructions. Lotic organisms also decreased after construction, especially Hydropsychidae (insecta: Trichoptera) acutely decreased from $3,526ind.\;m^{-2}$ to $2ind.\;m^{-2}$ As a result of CCA, lotic species such as Hydropsyche valvata, Hydropsyche kozhantschikovi, Cheumatopsyche brevilineata, Cheumatopsyche KUa, Macrostemum radiatum, etc. correlated with the flow velocity, streambed substrate. Therefore, the decrease of the flow velocity and substrate size after weir construction seemed to be closely related to the decrease of the individual abundances of the lotic organisms independently of water quality. In order to evaluate the influence of the ecosystem on the flow regime change more accurately, it is necessary to study the indicator species based on the resistance or preference of the flow.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.5
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• pp.78-90
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• 2019

The purpose of this study is to explore the direction of developing policies for parks and green spaces for inclusive urban planning and regeneration. By reviewing the status, budget, and laws pertaining to urban parks in Korea, as well as assessing the inclusivity of urban parks, this study revealed the problems and limitations in Korea as follows. First, the urban park system, which takes into account indicators such as park area per capita and green space ratio, is focused only on quantitative expansion. Second, the distribution of urban parks is unequal; hence, the higher the number of vulnerable residents, the lower the quality of urban parks and green spaces. Moreover, this study focused on the UK central government, along with the five local governments, including London, Edinburgh, Cardiff, Belfast, and Liverpool. Through an analysis of the contexts and contents establishing UK park and green space policies that can reduce socioeconomic inequalities while at the same time increase inclusiveness. This study discovered the following. The government's awareness of the necessity of tackling socioeconomic inequalities to make an inclusive society, the change in the urban regeneration policies from physical redevelopment to neighborhood renewal, and the survey and research on the correlation of parks and green spaces, inequality, health, and well-being provided the background for policy establishment. As a result, the creation of an inclusive society has been reflected in the stated goals of the UK's national plan and the strategies for park and green space supply and qualitative improvement. Deprived areas and vulnerable groups have been included in many local governments' park and green space policies. Also, tools for analyzing deficiencies in parks and methods for examining the qualitative evaluation of parks were developed. Besides, for the sustainability of each project, various funding programs have been set up, such as raising funds and fund-matching schemes. Different ways of supporting partnerships have been arranged, such as the establishment of collaborative bodies for government organizations, allowing for the participation of private organizations. The study results suggested five policy schemes, including conducting research on inequality and inclusiveness for parks and green spaces, developing strategies for improving the quality of park services, identifying tools for analyzing policy areas, developing park project models for urban regeneration, and building partnerships and establishing support systems.

• The Korean Journal of Archival Studies
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• no.33
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• pp.85-112
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• 2012

Group for the People without History(GPH) was launched at September 2002 and had worked for around five years with the following purposes; Firstly, GPH collects first-hand data on people's everyday lives based on fieldworks. Secondly, GPH constructs digital archives of the collected data. Thirdly, GPH guarantees the accessibility to the archives for people. And lastly, GPH promotes users to utilize the archived data for the various levels. GPH has influenced on the construction of archives on everyday life history as well as the research areas such as anthropology and social history. What is important is that GPH tried to construct digital archives even before the awareness on archives was not widely spreaded in Korea other than formal sectors. Furthermore, the GPH archives proposed a model of open archives which encouraged the people's participation in and utilization of the archives. GPH also showed the ways in which archived data were used. It had published forty seven books of people's life histories and five photographic books, and held six photographic exhibitions on the basis of the archived data. Though GPH archives had contributed to the ignition of the discussions on archives in various areas as leading civilian archives, it has a few limitations. The most important problem is that the data are vanishing too fast for researchers to collect. It is impossible for researchers to collect the whole data. Secondly, the physical space and hardware for the data storage should be ensured. One of the alternatives to solve the problems revealed in the works of GPH is to construct community archives. Community archives are decentralized archives run by people themselves to preserve their own voices and history. It will guarantee the democratization of archives.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.29-41
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• 2019

Terrestrial Gross Primary Production (GPP) is the largest global carbon flux, and forest ecosystems are important because of the ability to store much more significant amounts of carbon than other terrestrial ecosystems. There have been several attempts to estimate GPP using mechanism-based models. However, mechanism-based models including biological, chemical, and physical processes are limited due to a lack of flexibility in predicting non-stationary ecological processes, which are caused by a local and global change. Instead mechanism-free methods are strongly recommended to estimate nonlinear dynamics that occur in nature like GPP. Therefore, we used the mechanism-free machine learning techniques to estimate the daily GPP. In this study, support vector machine (SVM), random forest (RF) and artificial neural network (ANN) were used and compared with the traditional multiple linear regression model (LM). MODIS products and meteorological parameters from eddy covariance data were employed to train the machine learning and LM models from 2006 to 2013. GPP prediction models were compared with daily GPP from eddy covariance measurement in a deciduous forest in South Korea in 2014 and 2015. Statistical analysis including correlation coefficient (R), root mean square error (RMSE) and mean squared error (MSE) were used to evaluate the performance of models. In general, the models from machine-learning algorithms (R = 0.85 - 0.93, MSE = 1.00 - 2.05, p < 0.001) showed better performance than linear regression model (R = 0.82 - 0.92, MSE = 1.24 - 2.45, p < 0.001). These results provide insight into high predictability and the possibility of expansion through the use of the mechanism-free machine-learning models and remote sensing for predicting non-stationary ecological processes such as seasonal GPP.

• The Korean Journal of Archival Studies
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• no.45
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• pp.51-82
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• 2015

Maeul-making, which is to restore inherent characteristics of maeul as a living community has been proceeded by local communities themselves since the 1990s when political democracy and local government in Korean society has been progressed in full-scale. Although New Maeul Movement has been done in the 1970s before and after, it is different from maeul-making because it was focused mainly on improving physical environments of rural communities and initiated by government. The development of maeul community archives in Korea has been related closely to such a maeul-making since the 1990s. Maeul-based community archives, maeul community archives had been begun to build as part of maeul-making and grass-root movement by the 2000s. Initiated by self-motivated communities, maeul community archives were carried out through cooperations between civic activists and residents in maeul communities and voluntary professional archivists from outside. Although records about the maeul community has been collected by mainstream cultural institutions such as public archives, museum, local historical association, and local cultural center, it was at this time to collect records of the maeul community by self-motivated local residents. This tendency of 'independent' maeul community archives, however, is currently entering upon a new phase with the city of Seoul's project (2012) to support making a maeul community, that is, the governance phase based on private-government partnership. At this point of time, it is important for maeul community archives to be built on privately-led governance model that guarantees their autonomy and at the same time bring government's knowhow and supports into them, as opposed to the way captured or driven unilaterally by government. This article explores the growth of maeul community archives and collections in Korean society through a range of self-motivated bodies; the interaction with government; and as a result of those interactions, the creation of maeul community archives based on governance. To introduce and explicate the motivations behind maeul archiving endeavors, this article will first sketch something of the historical, social, and political context in which 'maeul' communities have arisen, collapsed, and restored. It will then examine in more detail some specific examples of maeul community archives as grass-root movement of maeul community. The third section will attempt to identify the governance model of maeul community archives under the auspices of the city of Seoul and its limitations. Finally through these activities, it will suggest the ways in which maeul community archives commit themselves to their duty of grass-root movement of community and at the same time, secure sustainability, that is, concrete ways of privately initiated governance model.

• Journal of Life Science
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• v.29 no.1
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• pp.76-83
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• 2019

In this study, the optimal growth and poly(3-hydroxybutyrate) (PHB) biosynthesis of Pseudomonas sp. EML2 were established using waste frying oil (WFO) as a cheap carbon source. The fatty acid composition of WFO and fresh frying oil (FFO) were analyzed by gas chromatography. The unsaturated and saturated fatty acid contents of the FFO were 82.6% and 14.9%, respectively. These contents changed in the WFO. The compositional change in the unsaturated fatty acid content in the WFO was due to a change in its chemical and physical properties resulting from heating, an oxidation reaction, and hydrolysis. The maximum dry cell weight (DCW) and PHB yield (g/l) of the isolated strain Pseudomonas sp. EML2 were confirmed under the following culture conditions: 30 g/l of WFO, 0.5 gl of $NH_4Cl$, pH 7, and $20^{\circ}C$. Based on this, the growth and PHB yield of Pseudomonas sp. EML2 were confirmed by 3 l jar fermentation. After the cells were cultured in 30 g/l of WFO for 96 h, the DCW, PHB content, and PHB yield of Pseudomonas sp. EML2 were 3.6 g/l, 73 wt%, and 2.6 g/l, respectively. Similar results were obtained using 30 g/l of FFO as a carbon source control. Using the FFO, the DCW, PHB content, and PHB yield were 3.4 g/l, 70 wt%, and 2.4 g/l, respectively. Pseudomonas sp. EML2 and WFO may be a new candidate and substrate, respectively, for industrial production of PHB.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.1
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• pp.92-105
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• 2019

Spatial and temporal characteristics of phytoplankton communities around the coastal waters of Jeju Island were investigated with environmental factors such as water temperature, salinity, and dissolved oxygen. Monthly samples were collected at 0 and 30 m depths of 10 stations from March 2015 to February 2016. During the survey period, water temperature ranged in 13.7~25.9 and $13.6{\sim}20.8^{\circ}C$ at 0 and 30 m, salinity in 31.51~34.47 and 33.03~34.47 psu at 0 and 30 m, and dissolved oxygen in 6.12~8.10 and $5.73{\sim}7.88mg\;L^{-1}$ at 0 and 30 m, respectively. Chlorophyll-a ranged in 0.28~2.48 and $0.44{\sim}1.01{\mu}g\;L^{-1}$ at 0 and 30 m, respectively. Phytoplankton abundance fluctuated in the range of $5,300{\sim}639,900cells\;L^{-1}$ during the year, showing the lowest in February at all stations, and the highest in July at the northern and western sea as well as in August at the southern and eastern sea of Jeju Island. A total of 362 species were occurred including 181 spp. of Bacillariophyta, 147 spp. of Dinophyta and 34 spp. of other phytoflagellates. Dominant species with occupancy rate over 20 percent of phytoplankton abundance showed apparent seasonal succession such as Paralia sulcata and Skeletonema costatum in spring and autumn, 6 spp. of genus Chaetoceros in summer, and 2 spp. of genus Chaetoceros and Thalassionema frauenfeldii in winter. Monthly abundance in the northern and western sea fluctuated with similar tendency, and the southern and eastern sea also showed similar pattern of monthly abundance variation. Species composition and dominant species succession mentioned above were quite different from previous studies, so some physical changes such as water temperature, salinity and current pattern might cause the changes of phytoplankton assemblages around Jeju Island.

• Journal of Astronomy and Space Sciences
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• v.36 no.1
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• pp.21-33
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• 2019

This paper focuses on the interpretation of radiation fluxes from active galactic nuclei. The advantage of positron annihilation spectroscopy over other methods of spectral diagnostics of active galactic nuclei (therefore AGN) is demonstrated. A relationship between regular and random components in both bolometric and spectral composition of fluxes of quanta and particles generated in AGN is found. We consider their diffuse component separately and also detect radiative feedback after the passage of high-velocity cosmic rays and hard quanta through gas-and-dust aggregates surrounding massive black holes in AGN. The motion of relativistic positrons and electrons in such complex systems produces secondary radiation throughout the whole investigated region of active galactic nuclei in form of cylinder with radius R= 400-1000 pc and height H=200-400 pc, thus causing their visible luminescence across all spectral bands. We obtain radiation and electron energy distribution functions depending on the spatial distribution of the investigated bulk of matter in AGN. Radiation luminescence of the non-central part of AGN is a response to the effects of particles and quanta falling from its center created by atoms, molecules and dust of its diffuse component. The cross-sections for the single-photon annihilation of positrons of different energies with atoms in these active galactic nuclei are determined. For the first time we use the data on the change in chemical composition due to spallation reactions induced by high-energy particles. We establish or define more accurately how the energies of the incident positron, emitted ${\gamma}-quantum$ and recoiling nucleus correlate with the atomic number and weight of the target nucleus. For light elements, we provide detailed tables of all indicated parameters. A new criterion is proposed, based on the use of the ratio of the fluxes of ${\gamma}-quanta$ formed in one- and two-photon annihilation of positrons in a diffuse medium. It is concluded that, as is the case in young supernova remnants, the two-photon annihilation tends to occur in solid-state grains as a result of active loss of kinetic energy of positrons due to ionisation down to thermal energy of free electrons. The single-photon annihilation of positrons manifests itself in the gas component of active galactic nuclei. Such annihilation occurs as interaction between positrons and K-shell electrons; hence, it is suitable for identification of the chemical state of substances comprising the gas component of the investigated media. Specific physical media producing high fluxes of positrons are discussed; it allowed a significant reduction in the number of reaction channels generating positrons. We estimate the brightness distribution in the ${\gamma}-ray$ spectra of the gas-and-dust media through which positron fluxes travel with the energy range similar to that recorded by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) research module. Based on the results of our calculations, we analyse the reasons for such a high power of positrons to penetrate through gas-and-dust aggregates. The energy loss of positrons by ionisation is compared to the production of secondary positrons by high-energy cosmic rays in order to determine the depth of their penetration into gas-and-dust aggregations clustered in active galactic nuclei. The relationship between the energy of ${\gamma}-quanta$ emitted upon the single-photon annihilation and the energy of incident electrons is established. The obtained cross sections for positron interactions with bound electrons of the diffuse component of the non-central, peripheral AGN regions allowed us to obtain new spectroscopic characteristics of the atoms involved in single-photon annihilation.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.161-171
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• 2019

The purposes of this study are: 1) to verify the systems thinking factor structure of elementary school students and 2) to compare systems thinking according to their preferred subjects in order to get implications for following research. For the study, pre-tests analyze data from 732 elementary school students using the STMI (Systems Thinking Measuring Instrument) developed by Lee et al. (2013). And exploratory factor analysis was conducted to identify the factor structure of the students. Based on the results of the pre-test, the expert group council revised the STMI so that elementary school students could respond to the 5-factor structure that STMI intended. In the post-test, 503 data were analyzed by modified STMI and exploratory factor analysis was performed. The results of the study are as follows: First, in the pre-test, elementary school students responded to the STMI with a test paper consisting of two factors (personal internal factors and personal external factors). The total reliability of the instrument was .932 and the reliability of each factor was analyzed as .857 and .894. Second, for modified STMI, elementary school students responded a 4-factor instrument. Team learning, Shared Vision, and Personal Mastery were derived independent factors, and mental model and systems analysis were derived 1-factor. The total reliability of the instrument was .886 and the reliability of each factor was analyzed as .686 to .864. Finally, a comparison of systems thinking according to preferred subjects showed a significant difference between students who selected science (engineering) group and art (music and physical education). In conclusion, it was confirmed that statistically meaningful results could be obtained using STMI modified by term and sentence structure appropriate for elementary school students, and it is a necessary to study the relation of systems thinking with various student variables such as the preferred subjects.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.1
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• pp.1-11
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• 2019

This study was conducted to analyze the conservation status by diagnostical methology for the front wall of Jungjeongdang area of Dodong-Seowon. The study was carried out as photogrammetry and mapping - investigation of materials and conservation status - analysis and evaluation of conservation status. The results are as follows. First, in the case of photogrammetry, each photograph was took in superposition, and the distortions of the photographs were corrected and synthesized. Based on this, actual survey drawings of the wall were prepared. Second, in case of material and conservation status, the wall is in the form of Wapyeondam and the material of the head part are tile, mud and lime, and the material of the body part are mud and tile. The mud was mixed with gravel, sand and straw. At the base part, amorphous natural stones and mud were used. The remarkable damage that appears on the wall is erosion of the base part, and some disintegration appears in the body part. There is a biological patina on the head and the base, and vegetation such as lichen is concentrated on the partial body. There was superficial deposit in the head part, and some tiles were broken or lost. Deep fissures are intensively located in some part of the eastern wall. Third, in the case of analysis and evaluation of the conservation status, it is considered that by the erosion of the foundation part and the disintegration of the body part, there is a possibility that physical damage will continue to be applied to the wall, so immediate action is necessary. The distribution of biological patina and vegetation does not appear to cause great problems in the wall, but it is necessary to reduce it in view of aesthetic problems. A cracked or missing tile would need to be replaced, and deep cracks in the eastern wall appear to have been caused by subsidence, and reinforcement of the underground is necessary to prevent further damage.