• Journal of Korean Society for Atmospheric Environment
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• v.15 no.3
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• pp.317-325
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• 1999

The demand of diesel engine on the construction equipment has been rapidly increased because of high thermal efficiency and fuel economy. The exhaust emission from nonroad vehicles equipped with diesel engine such as construction equipment, ship, and agricultural equipment, etc. Which are known to be harmful to human health and environment, has not been regulated in our country. But the regulation for nonroad vehicle has been already progressed in advanced country. So we investigated the contribution ratio of air pollution by construction equipment in order to establish the exhaust emission management strategy for nonroad vehicle. Based on the statistical data for construction equipment, 5 kinds of equipment are selected and tested in the engine dynamometer to determine the emission factor. And the amount of air pollutant from construction equipment are calculated by using of the emission factor and recommended exhaust emission standard for construction equipment.

• Journal of Korean Society for Atmospheric Environment
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• v.6 no.2
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• pp.135-146
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• 1990

The purpose of the study was to identify sources of particulate matters statistically and to estimate the mass contribution quantitatively in the Pusan metropolitan area. Then, the study has used the TTFA (target transformation factor analysis) model, a receptor model, to apportion aerosol mass with the raw data of 106 ambient samples characterized by 24 heavy metal variables. The TTFA was extensively applied to generate source profiles and their aerosol mass contributions. Though a couple of sources were not identified, four to seven sources were able to be extracted at 3 different sites (Jang Rim-Dong, Kwang Bok-Dong, and Kwang An-Dong) in Pusan area and finally mass conributions could be calculated.

• Biomolecules & Therapeutics
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• v.28 no.1
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• pp.45-57
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• 2020

In the neurovascular unit, the neuronal and vascular systems communicate with each other. O₂ and nutrients, reaching endothelial cells (ECs) through the blood stream, spread into neighboring cells, such as neural stem cells, and neurons. The proper function of neural circuits in adults requires sufficient O₂ and glucose for their metabolic demands through angiogenesis. In a central nervous system (CNS) injury, such as glioma, Parkinson's disease, and Alzheimer's disease, damaged ECs can contribute to tissue hypoxia and to the consequent disruption of neuronal functions and accelerated neurodegeneration. This review discusses the current evidence regarding the contribution of oxygen deprivation to CNS injury, with an emphasis on hypoxia-inducible factor (HIF)-mediated pathways and Notch signaling. Additionally, it focuses on adult neurological functions and angiogenesis, as well as pathological conditions in the CNS. Furthermore, the functional interplay between HIFs and Notch is demonstrated in pathophysiological conditions.

• Journal of Environmental Science International
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• v.17 no.3
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• pp.315-323
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• 2008

Based on the result of extraction of common factors executed in order to elucidate the visual attributes of street scenery by types through the rotation of 23 adjective variables by Varimax, the visual attributes expressed after the construction of the facilities using street scenery were anylized to be 4 factors including factor 1 through factor 4. Theexplanation of the 4 factor groups to explain the entire distribution was 65.3% and these factor groups are the psychological attributes felt when using facilities are constructed by securing the street spaces in downtowns and the factors were named as naturalness(factor 1), locality(factor 2), identity(factor 3) and clarity(factor 4) respectively. Based on the result of one-way layout distribution analysis, the preferences for street scenery by types were found out to show considerable differences at 1 % significance level. Based on the result of multiple regression analysis, all of the factors explaining preferences including factor 1 through factor 4 were significant at 1 % significance level. In case other conditions are constant, if the values of the adjective variables related to locality(factor 2) increase by 1 unit, the preferences which are the values of dependent variables will increase by 0.709. The variable with the largest relative contribution among the 4 factor groups was the locality(factor 2) factor group and on the contrary, it was found that the independent variable with least influences was the clarity(factor 4) factor group.

• Tribology and Lubricants
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• v.10 no.4
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• pp.13-26
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• 1994

Effects of resin contents, number of carbonization, graphitization, sliding speed, and oxidation on friction and wear behavior of carbon/carbon composite materials were investigated. Friction and wear tests were carried out under various sliding conditions. An experimental setup was designed and built in the laboratory. Stainless steel disks were used as the counterface material. Friction coefficient, emperature, and wear factor were measured with a data acquisition system. Wear surfaces were observed by the scanning electron microscope. It has been shown that the average friction coefficient was increased with the sliding speed in the range of 1.43~6.10 m/s, but it as decreased in the range of 6.10~17.35 m/s. Specimens prepared by different numbers of carbonization. showed variations in friction coefficient and friction coefficient of the graphitized specimen was the highest. Friction coefficients depended on contribution of the plowing and adhesive components. As the number of carbonization was increased, wear factor was reduced. Wear factor of the graphitized specimens dropped further. In the case of graphitized specimens, sliding speed had a large influence on wear behavior. When the tribological experiments were conducted in nitrogen atmosphere, the wear factor was decreased to two thirds of the wear factor obtained in air. It is obvious that the difference was affected by oxidation. Results of friction and wear tests were applied to a neural network system based on the backpropagation algorithm. A neural network may be a valuable tool for prediction of tribological behavior of the carbon/carbon composite material if ample data are present.

• Journal of the Korean Home Economics Association
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• v.41 no.6
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• pp.119-129
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• 2003

This study was peformed to establish the standard size system to be required for the production of brassiere. The subject were 155 Korean twenties-aged women and were directly measured anthropometrically. From 27 measurements, 5 factors were extracted through factor analysis. The accumulative contribution ratio is 76.92％. Factor 1 indicates the degree of obesity around the chest, factor 2 is the drooping degree of breast, factor 3 is the contours and prominence, factor 4 is the breast breadth and breadth of bust point, factors 5 is the volume of breast. The subject were classified into 3 cluster as their breast types through cluster analysis. Type 1 is the closest to the ideal breast shape and not too droopy. This group belonged to 75A. Type 2 has small breast and belonged to 70AA group. Type 3 is the obesest and has the biggest and droopy breast. This group belonged to 75B. The distribution of size of brassiere had 3 sections from 70 to 80 showing a rate of 81.94% and the sin of the cup had 4 sections from AAA cup to B cup showing a rate of 89.70％. The production ratio of each brassiere size, it was found that the brassiere size of highest production ratio was 75A(16.39％) in type 1,70AA(16.27%) in type 2, and 75B(13.72％) in type 3. This suggests that it is necessary to adjust for the production rate of brassieres.

• Journal of Korea Port Economic Association
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• v.23 no.4
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• pp.49-69
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• 2007

The purpose of this study is to analyze contribution factors of economic growth through growth accounting analysis in Korean port-logistics industry. Comparing with the average level of entire industry for 1990-2003, the contributions of total factor productivity and labor in port-logistics industry were high, but that of capital stock was very low. The pattern of growth in Korean port-logistics industry has greatly changed before and after Korean financial crisis. Before the 1997 financial crisis, the economic growth rate of port-logistics industry was 14.1%, which is higher than that of the whole industries, 7.7% for 1990-1998. Main contribution factors of the economic growth rate were the growth of capital stock and productivity, but ratios of their contributions were relatively low and did not come up to that for the whole industry. After the financial crisis, annualized growth rate of GDP in port-logistics industry had rapidly declined at 5.4% for 1998-2003, which did not get to that of the entire industry (10.1%). The main contribution factors of the economic growth rate over the 1998-2003 period were capital stock 13.1%, labor 57.0 %, and total factor productivity 29.9 %, Such growth pattern as excess dependence on growth of labor brought reduction of the rate of economic growth with degradation of productivity growth in the Korean port-logistics industry.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.1
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• pp.47-55
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• 2021

The objective of this study was to access the effect of climate and soil factors on alfalfa dry matter yield (DMY) by the contribution through constructing the yield prediction model in a general linear model considering climate and soil physical variables. The processes of constructing the yield prediction model for alfalfa was performed in sequence of data collection of alfalfa yield, meteorological and soil, preparation, statistical analysis, and model construction. The alfalfa yield prediction model used a multiple regression analysis to select the climate variables which are quantitative data and a general linear model considering the selected climate variables and soil physical variables which are qualitative data. As a result, the growth degree days(GDD) and growing days(GD), and the clay content(CC) were selected as the climate and soil physical variables that affect alfalfa DMY, respectively. The contributions of climate and soil factors affecting alfalfa DMY were 32% (GDD, 21%, GD 11%) and 63%, respectively. Therefore, this study indicates that the soil factor more contributes to alfalfa DMY than climate factor. However, for examming the correct contribution, the factors such as other climate and soil factors, and the cultivation technology factors which were not treated in this study should be considered as a factor in the model for future study.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.600-608
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• 2013

Amide analogs of tridecapeptide ${\alpha}$-factor (WHWLQLKPGQPMYCONH$_2$) of Saccharomyces cerevisiae, in which Trp at position 1 and 3 were replaced with other residues, were synthesized to ascertain whether cooperative interactions between two Trp residues occurred upon binding with its receptor. Analogs containing Ala or Aib at position 3 of the peptide $[Ala_3]{\alpha}$-factor amide (2) and $[Aib_3]{\alpha}$-factor amide (5) exhibited greater decreases in bioactivity than analogs with same residue at position one $[Ala^1]{\alpha}$-factor amide (1) and $[Aib^1]{\alpha}$-factor amide (4), reflecting that $Trp^3$ may plays more important role than $Trp^1$ for agonist activity. Analogs containing Ala or Aib in both position one and three 3, 6 exhibited complete loss of bioactivity, emphasizing both the essential role and the combined role of two indole rings for triggering cell signaling. In contrast, double substituted analog with D-Trp in both positions 9 exhibited greater activity than single substituted analog with D-Trp 8 or deleted analog 7, reflecting the combined contribution of two tryptophane residues of ${\alpha}$-factor ligand to activation of Ste2p through interaction with residue $Tyr^{266}$ and importance of the proper parallel orientation of two indole rings for efficient triggering of signal G protein coupled activation. Among ten amide analogs, $[Ala^{1,3}]{\alpha}$-factor amide (3), $[Aib^{1,3}]{\alpha}$-factor amide (6), [D-$Trp^3]{\alpha}$-factor amide (8) and [des-$Trp^1,Phe^3]{\alpha}$-factor amide (10) were found to have antagonistic activity. Analogs 3 and 6 showed greater antagonistic activity than analogs 8 and 10.

• Journal of Photoscience
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• v.3 no.3
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• pp.147-151
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• 1996

Dynamics of contact ion-pair between 1, 2, 4, 5-tetracyanobenzene anion and cation of biphenyl derivatives was investigated on the picosecond time scale. Solvent effect on the electron transfer was observed and electron transfer rates were examined using Marcus equation which contains distance dependence of the electron transfer rate in the frequency factor, along with the consideration of molecular shape. From the discussion based on disk model for molecular shape, contribution of interring torsional motion of biphenyl to the inner-sphere reorganization energy is strongly suggested, which leads to the physical explanation for the observed solvent effect on the rate of electron transfer.