• Korean Journal of Remote Sensing
• /
• v.27 no.3
• /
• pp.329-338
• /
• 2011

The time-series normalized difference vegetation index (NDVI) product has proven to be a powerful tool to investigate the phenological information because it can monitor the change of the forests with very high time-resolution, This study described the application of the DFT analysis over the 9 year MODIS data for the identification of the two types of vegetation cover, Pinus densiflora(Pd) and Querqus mongolica(Qm) which are dominant species of evergreen and broadleaved deciduous forest, respectively, The total number of samples was 5148 reference cycles which consist of 2160 Pd and 2988 Qm. They were extracted from the pixel-based MODIS scenes over the 9 years from 2000 to 2008 of South Korea. The DFT analysis was mainly focused on the 0th and $1^{st}$ harmonic components, each of which represents the mean value and the variation amplitude of the NDVI over the years, respectively. The $0^{th}$ harmonic values of the vegetation Pd and Qm averaged over the 9 years were 0.74 and 0.65, respectively. This implies that Pd has a higher NDVI than Qm. Similarly obtained $1^{st}$ harmonic values of Pd and Qm were 0.19 and 0.27, respectively. This can be intuitively understood considering that the seasonal variation of Qm is much larger than Pd. This distinctive difference of the $1^{st}$ harmonic value has been used to identify evergreen and deciduous forests. Overall agreement between the Fourier analysis-based map and the actal vegetation map has been estimated to be as high as 75%. This study found that the DFT analysis can be a concise and repeatable method to separate and trace the changes of evergreen and deciduous forest using the annual NDVI cycles.

• Journal of Veterinary Clinics
• /
• v.33 no.1
• /
• pp.1-5
• /
• 2016

Septic tenosynovitis of the digital flexor tendon sheath (DFTS) is a potentially career-ending and life-threatening problem in horses. This study aimed to describe the outcomes of tenoscopy for the treatment of acute septic digital flexor tenosynovitis in horses. Tenoscopy was performed on 13 Thoroughbred horses with acute septic tenosynovitis of the DFTS. Surgical time was 56-148 min (mean 85.6 min, median 84.0 min). In the synovial fluid analysis, mean white blood cell count, mean neutrophil proportion, and mean total protein were $42.9{\times}10^3cells/{\mu}l$ (range, $7.2-109.5cells/{\mu}l$), 89.5% (range, 68-97%), and 4.0 g/dl (range, 2.5-5.2 g/dl), respectively. Microbial growth in the synovial fluid culture was detected in 2 of 11 horses. All horses survived and returned to their intended use without complications. The present study demonstrated that the tenoscopy is useful for treating acute septic tenosynovitis of the DFTS in horses.

• Applied Science and Convergence Technology
• /
• v.25 no.1
• /
• pp.19-24
• /
• 2016

In this study, we evaluated the change of electronic structure during redox process in cerium-doped $ZrO_2$ grown by sol gel method. By sol-gel method, we could obtain cerium-doped $ZrO_2$ in high oxygen partial pressure and low temperature. After post annealing process in nitrogen ambient, the film is deoxidized. We used spectroscopic and theoretical methods to analysis change of electronic structure. X-ray absorption spectroscopy (XAS) for O K1-edge and Density Functional Theory (DFT) calculation using VASP code were performed to verify the electronic structure of the film. Also, high resolution x-ray photoelectron spectroscopy (HRXPS) for Ce 3d was carried out to confirm chemical bond of cerium doped $ZrO_2$. Through the investigation of the electronic structure, we verified as followings. (1) During reduction process, binding energy of oxygen is increase. Simultaneously, oxidation state of cerium was change to 4+ to 3+. (2) Cerium 4+ and cerium 3+ states were generated at different energy level. (3) Absorption states in O K edge were mainly originated by Ce 4+ $f_0$ and Ce 3+, while occupied states in valance band were mainly originated from Ce 4+ $f_2$.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.8
• /
• pp.2219-2222
• /
• 2010

A density functional theory (DFT) study of $CO_2$ adsorption on barium oxide (BaO) adsorbents is conducted to understand the chemical activity of the oxygen site on the BaO (100) surface. This study evaluated the adsorption energies and geometries of a single $CO_2$ molecule and a pair of $CO_2$ molecules on the BaO (100) surface. A quantum calculation was performed to obtain information on the molecular structures and molecular reaction mechanisms; the results of the calculation indicated that $CO_2$ was adsorbed on BaO to form a stable surface carbonate with strong chemisorption. To study the interactive $CO_2$ adsorption on the BaO (100) surface, a pair of $CO_2$ molecules was bound to neighboring and distant oxygen sites. The interactive $CO_2$ adsorption on the BaO surface was found to slightly weaken the adsorption energy, owing to the interaction between $CO_2$ molecules.

• Korean Chemical Engineering Research
• /
• v.55 no.2
• /
• pp.270-274
• /
• 2017

Formic acid has been known as one of key sources of hydrogen. Among various monometallic catalysts, hydrogen can be efficiently produced on Pd catalyst. However, the catalytic activity of Pd is gradually reduced by the blocking of active sites by CO, which is formed from the unwanted indirect oxidation of formic acid. One of promising solutions to overcome such issue is the design of alloy catalyst by adding other metal into Pd since alloying effect (such as ligand and strain effect) can increase the chance to mitigate CO poisoning issue. In this study, we have investigated formic acid deposition on the bimetallic $Pd/Pd_3Fe$ core-shell nanocatalyst using DFT (density functional theory) calculation. In comparison to Pd catalyst, the activation energy of formic acid dehydrogenation is greatly reduced on $Pd/Pd_3Fe$ catalyst. In order to understand the importance of alloying effects in catalysis, we decoupled the strain effect from ligand effect. We found that both strain effect and ligand effect reduced the binding energy of HCOO by 0.03 eV and 0.29 eV, respectively, compared to the pure Pd case. Our DFT analysis of electronic structure suggested that such decrease of HCOO binding energy is related to the dramatic reduction of density of state near the fermi level.

• Journal of Korean society of Dental Hygiene
• /
• v.5 no.1
• /
• pp.15-27
• /
• 2005

The purpose of this study was to assess how mothers' oral health behaviour, knowledge, and socio-demographic characteristics influence on dental caries status of their children. The 142 children and their mothers were selected for this study. The children were 5 and 6 years old in the three day care centers in Ulsan, Korea. Date were collected by oral examination on children and self-administrated questionnaire on their mothers. The questionnaire was surveyed mothers' behaviour and know ledge of oral health and their socio-demographic characteristics. The findings of this study were summarized as follows: 1. The higher mother's educational level and the greater children members, the higher degree of oral health knowledge, but there was no significant relation. 2. There was significant relationship between working mothers and correct toothbrushing, between monthly mean income and important for oral health. 3. The dft index was lower when the higher mother's oral health knowledge, the larger toothbrushing frequency, preventive dental visit.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.4 no.1
• /
• pp.45-52
• /
• 1977

The purpose of this study was to provide information concerning the dental caries incidence in cerebral palsy children, and to aid improvement of their oral health. The author examined 106 cerebral palsy children and 185 normal children as control group, between 3 and 15 years of age. The obtained results were as follows: 1) In the DMF person rate, DMFT rate and DMFT index, cerebral palsy children (74.68%, 16.24% and 2.76 respectively) showed remarkable increment compare to normal children. (14.28%, 6.95% and 1.20 respectively.) 2) In the df person rate, dft rate and dft index, cerebral palsy children(93.33%, 37.41% and 6.22 respectively) showed remarkable increment compare to normal children. (78.64%, 20.68% and 3.29 respectively.) 3) There showed no significant in sexual differences. 4) In the dental caries incidence of the permanent teeth, athetosis and paraplegia type was found higher than other types. 5) Cerebral palsy children was found higher than normal children in the oral hygiene index. 6) There was found out necessity of the continuous dental enlightenment and treatment through this study.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.5
• /
• pp.1421-1423
• /
• 2010

• Bulletin of the Korean Chemical Society
• /
• v.33 no.3
• /
• pp.1052-1054
• /
• 2012

• Bulletin of the Korean Chemical Society
• /
• v.31 no.2
• /
• pp.500-502
• /
• 2010