• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.471-475
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• 2004

The solubility of N,N'-Bis(salicylidene) ethylenediamine (n-salen) and N,N'-bis(3,5-di-tert-butylsalicylidene) ethylenediamine (t-butyl-salen) was studied with in-situ UV-VIS spectrometer. n-Salen is 3-5 times more soluble than t-butyl-salen in liquid or supercritical $CO_2$. This behavior may be attributed to Lewis acid-base interaction between salen and $CO_2$. The chelation of salen with $Co^{++}$ ion in supercritical condition was confirmed to be fast enough above room temperature. However, the metal ion extraction capability of t-butyl salen is relatively poor because of its low solubility and ionic nature of complex.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.379-382
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• 2009

As IT becomes leading part of futurity industry, issue about Green IT is being on the increase and resources recycling, toxicity water use resection, saveenergy etc. are emphasized. Fundamental purpose for Neteuwokeusiseutem's Green IT realization that is constructed on ship studied about network security system that can control access that use resources as efficient and safe and is enemy of evil which can give subordinate of system for this and resect unnecessary hardware waste by back more.

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.423-427
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• 2005

The bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex-272) and sodium diethyl- dithiocarbamate (NaDDC) ligands were used to extract of metal ions ($Cd^{2+},\;Co^{2+},\;Cu^{2+},\;Pb^{2+},\;Zn^{2+}$) in supercritical $CO_2$. Experiments showed a strong synergistic effect and better extraction efficiency if the two ligands were used together. In-situ UV-visible observation indicates that NaDDC in the water/supercritical $CO_2$ started to decompose slowly. The synergistic effect seems to come from the deprotonation of the organophosphorus ligand by amines from the decomposed NaDDC. The enhancing role of amines was confirmed using the mixture of Cyanex-272 and diethylamine(DEA) in the metal extraction.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.3
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• pp.349-354
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• 2020

The preliminary investigation to expand the green space requires a lot of cost and time. In this paper, we solve the problem by measuring the ratio of green space in a specific region through a convolutional neural network based the green space classification using Google Earth images. First, the proposed method collects various region images in Google Earth and learns them by using the convolutional neural network. The proposed method divides the image recursively to measure the green space ratio of the specific region, and it determines whether the divided image is green space using a trained convolutional neural network model, and then the green space ratio is calculated using the regions determined as the green space. Experimental results show that the proposed method shows high performance in measuring green space ratios in various regions.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.101-112
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• 2021

In Korea, efforts have been made continuously to improve the environment of traditional markets concerning the issues of urban regeneration. In particular, many old cities and traditional markets face a lack of parking spaces. As a solution to this, attempts are being made to prepare underground parking spaces by designing urban planning facilities in three-dimensional ways and utilizing the upper part as a more meaningful space. This study is about the master plan to use the upper green area while creating an underground parking lot at 571 Sinmae-dong, Suseong-gu, Daegu. This green area was defined as a space with dual values, 'defensive green space' that needs to be ecologically protected, and 'active cultural space' where walking flows to the market and various events are concentrated. Three specific design strategies to balance these values were presented. First, to prevent indiscriminate occupation and damage by people and maintain a healthy green environment, securing the maximum amount of undivided green space in the site was suggested. Second, a space layout and a topography and planting patterns that can overcome the morphological characteristics of narrow and long-shaped sites enable the experience of abundant green spaces. Third, providing space to strengthen the connections with nearby urban facilities such as Sinmae Market and Gosan Library can also intensively accommodate cultural activities in various cities. This study has academic significance in providing implications for urban regeneration projects with similar contexts in the future.

• Journal of the Korean Data and Information Science Society
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• v.14 no.4
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• pp.975-982
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• 2003

In this paper we considered the problem of estimating the bivariate survival distribution of the random vector (X, Y) when Y may be subject to random censoring but X is always uncensored. Adapting conditional Koziol-Green model, simplified estimator for bivariate survival function is proposed. We perform simulation to compare the proposed estimator with popular estimators and discussed the performance of it.

• Korean Journal of Environment and Ecology
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• v.26 no.5
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• pp.801-811
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• 2012

The purpose of this study is to find out how land cover and planting of an urban park influence temperature. Field research on the land cover and planting status was conducted for Bundang Central Park in Sungnam-si. 30 study plots in the site were selected to closely analyze land cover type and planting structure. The temperature was measured 10 times for each plot. Land coverage type, planting type, planting layer structure and green space area (the ratio of green coverage, GVZ) were chosen as factors impacting temperature and statistics were analyzed for the actual temperature measured. Analysis on how the land coverage type influences temperature showed that planting site had a low temperature and that grassland and paved land had a high temperature. When it comes to planting type, the temperature at the land planted with conifers and broad-leaved trees was low, while the temperature at grassland and paved land was high. With regard to planting layer structure, canopy and canopy-underplanting type showed low temperature, while grassland and paved land showed high temperature. An analysis on the relation between green space area and temperature found out that both ratio of green coverage and GVZ had a high level of negative correlation with the temperature measured. According to regression model of green space area and the temperature measured, for every 1% increase in the ratio of green coverage, temperature is expected to lower by $0.002^{\circ}C$. Also, for every $1m^3/m^2$ increase in GVZ, temperature is expected to go down by $0.122^{\circ}C$.

• 한국약용작물학회:학술대회논문집
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• 2010.10a
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• pp.557-558
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• 2010

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.47-48
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• 1979

To study on the state of nitrogen fixation of Lemma associated with blue green algae this experiment was carried out. The results were as follows: 1) The blue green algaes associated with Lemnaceae were mainly Calthrix sp. and Microcrate sp., but Anabaena sp. was found only in L. gibba. 2) It was believed that Lemnaceae associated with blue green algae have semi-symbiotic nitrogen fixation ability, especially clear in L. oligorhiza.

• ALGAE
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• v.20 no.3
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• pp.197-205
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• 2005

Temporal variability in lake phytoplankton is controlled by a complex between hydrological and chemical factors, and biological interactions. We explored annual change of phytoplankton in Lake Daecheong, using phytoplankton analysis data from 1997 to 2002 (except 2000). The standing crop of phytoplankton was ranged from 3.5 x 10 to 1.5 x 106 cells mL$^{-1}$ and the highest mean value was at site 1. The class composition ratios of phytoplankton standing crop were divided into three classes. From January to March, diatoms showed a dominance (68.1-77.7%). From April to June, diatoms were mixed with cryptomonad etc. or blue-green algae. From July to October, blue-green algae showed a dominance (54.7-84.0%). In the case of green algae, the class composition ratios were below 10%. But green algae appeared all the year round.