• Tuberculosis and Respiratory Diseases
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• v.54 no.4
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• pp.429-438
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• 2003

Background : The mortality from acute respiratory distress syndrome(ARDS) is >40-50%. Although some prospective trials have failed to demonstrate a survival benefit of steroids in the early stages of ARDS, there are some reports showing some success with steroids in the later stages. This study observed the changes in the physiologic parameters with time in late ARDS patients who were treated with steroids. Methods : The medical charts of 28 intensive care unit patients(male:female=24:4; mean age 64 years), who had been diagnosed with refractory late ARDS ($PaO_2/FIO_2$ <200) and were treated with corticosteroids from December 1999 to July 2002, were retrospectively reviewed. The patients were divided into two groups: the weaned group(n=14), which included the patients who had been successfully weaned from a ventilator after corticosteroid therapy, and the failed group(n=14), which included the patients who had failed weaning. The physiologic parameters included the $PaO_2/FIO_2$ ratio, the positive end-expiratory pressure(PEEP) level, the $PaCO_2$, compliance, the sequential organ failure assessment(SOFA) score, the acute physiologic and the chronic health evaluation(APACHE) II score, and the Murray Lung Injury Score(LIS) in the two groups were compared from the day of mechanical ventilation(Dmv) to 7 days after the corticosteroid therapy. Results : There was no significant difference in the clinical characteristics and the physiologic parameters between the two groups prior to the corticosteroid therapy except for the SOFA score at Dmv(weaned group : $6.6{\pm}2.5$ vs failed group : $8.8{\pm}2.9$, p=0.047). However, within 7 days after corticosteroid therapy, there was significant improvement in the $PaO_2/FIO_2$ ratio, the PEEP level, the $PaCO_2$, the SOFA score, the APACHE II score, and the LIS of the weaned group compared to the failed group. Conclusions : During corticosteroid therapy in late ARDS, the continuation of corticosteroid therapy should be determined carefully in patients who do not show improvement in their physiologic parameters by day 7.

• Applied Chemistry for Engineering
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• v.23 no.2
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• pp.148-152
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• 2012

Anatase and anatase/rutile $TiO_2$ samples were prepared at $HNO_3$/TTIP molar ratio of 0.1, 0.5, 1.0, and 1.5 to study the effects of the physical properties of $TiO_2$ on photocatalytic decomposition of methylene blue. The physical properties of the samples were measured with XRD, SEM, TEM, BET, FT-IR, and UV-vis spectroscopy. Anatase phase was observed at $HNO_3$/TTIP of 0.1 and anatase/rutile phases were observed at $HNO_3$/TTIP of 0.5~1.5. Rutile crystal phase, mesopore size between $TiO_2$ nanoparticles, and surface OH group on $TiO_2$ sample were gradually increased with increasing the molar ratio of $HNO_3$/TTIP and the residual methylene blue concentration before UV irradiation decreased from 78.0 to 53.3%. After UV irradiation, the residual methylene blue concentrations of the samples prepared at $HNO_3$/TTIP of 0.1, 0.5, 1.0, and 1.5 were 20, 14, 11, and 23%, respectively, and the sample prepared at $HNO_3$/TTIP of 1.0 showed the best photocatalytic ability.

• Progress in Superconductivity and Cryogenics
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• v.18 no.4
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• pp.1-4
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• 2016

We investigated the relation between the Cu-O bond length and the superconducting properties of $BaSnO_3$ (BSO)-added $GdBa_2Cu_3O_{7-x}$ (GdBCO) thin films by using extended x-ray absorption fine structure (EXAFS) spectroscopy. 4 wt.% $BaSnO_3$ (BSO) added $GdBa_2Cu_3O_{7-x}$ (GdBCO) thin films with varying thickness from $0.2{\mu}m$ to $1.0{\mu}m$ were fabricated by using pulsed laser deposition (PLD) method. The transition temperature ($T_c$) and the residual resistance ratio (RRR) of the GdBCO films increased with increasing thickness up to $0.8{\mu}m$, where the crystalline BSO has the highest peak intensity, and then decreased. This uncommon behaviors of $T_c$ and RRR are likely to be created by the addition of BSO, which may change the ordering of GdBCO atomic bonds. Analysis from the Cu K-edge EXAFS spectroscopy showed an interesting thickness dependence of ordering behavior of BSO-added GdBCO films. It is noticeable that the ordering of Cu-O bond and the transition temperature are found to show opposite behaviors in the thickness dependence. Based on these results, the growth of BSO seemingly have evident effect on the alteration of the local structure of GdBCO film.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.6
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• pp.410-415
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• 1999

$Ba_{1-x}Sr_xTiO_3$ thin films with various ratio of Sr (X = 0.4, 0.5, 0.6) were grown $Pt/TiN/SiO_2/Si$ subastrate by RF magnetron sputtering deposition. As, Ag, and Cu films were deposited on $Ba_{1-x}Sr_xTiO_3$ thin films as top electrodes by using a thermal evaporator. The electrical properties of $Ba_{1-x}Sr_xTiO_3$ thin films for various compositions were characterized and the physical properties at interface between $Ba_{1-x}Sr_xTiO_3$ thin films and top electrodes were evaluated in terms of the work function difference. At x =0.5, the degradation of capacitance is lower to the other compositions. As negative biasapplied, the specimen with Cu top electrode has board saturation region and low leakage current since work function of Cu is bigger than other electrodes.$ Ba_{0.5}Sr_{0.5}TiO_3$ thin films with Cu top electrode, the dielectric constant was measured to the value of 354 at 1 kHz and the leakage current was obtained to the value of $5.26\times10^{-6}A/cm2$ at the forward bias of 2 V.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.377-377
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• 2011

Organic solar cells (OSCs) with low cost have been studied to apply on flexible substrate by solution process in low temperature [1]. In previous researches, conventional organic solar cell was composed of metal oxide anode, buffer layer such as PEDOT:PSS, photoactive layer, and metal cathode with low work function. In this structure, indium tin oxide (ITO) and Al was generally used as metal oxide anode and metal cathode, respectively. However, they showed poor reliability, because PEDOT:PSS was sensitive to moisture and air, and the low work function metal cathode was easily oxidized to air, resulting in decreased efficiency in half per day [2]. Inverted organic solar cells (IOSCs) using high work function metal and buffer layer replacing the PEDOT:PSS have focused as a solution in conventional organic solar cell. On the contrary to conventional OSCs, ZnO and TiO2 are required to be used as a buffer layer, since the ITO in IOSC is used as cathode to collect electrons and block holes. The ZnO is expected to be excellent electron transport layer (ETL), because the ZnO has the advantages of high electron mobility, stability in air, easy fabrication at room temperature, and UV absorption. In this study, the IOSCs based on poly [N-900-hepta-decanyl-2,7-carbazole-alt-5,5-(40,70-di-2-thienyl-20,10,30-benzothiadiazole)] (PCDTBT) : [6,6]-phenyl C71 butyric acid methyl ester (PC70BM) were fabricated with the ZnO electron-transport layer and MoO3 hole-transport layer. Thickness of the ZnO for electron-transport layer was controlled by rotation speed in spin-coating. The PCDTBT and PC70BM were mixed with a ratio of 1:2 as an active layer. As a result, the highest efficiency of 2.53% was achieved.

• Korean Membrane Journal
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• v.3 no.1
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• pp.69-74
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• 2001

Films of TiO$_2$/SiO$_2$ were deposited on the inner surface of the porous glass support tubes by decomposition of tetraisopropyl titanate (TIPT) and tetraethyl orthosilicate (TEOS) at atmospheric pressure. Dense and hydrogen -permselective membranes were formed at 400-600$\^{C}$. The permeation rates of H$_2$ through the membrane at 600$\^{C}$ were 0.2-0.4 ㎤(STP)/min-㎠ atm and H$_2$:N$_2$permeation ratios were above 1000. The permeation properties of the membranes were investigated at various deposition temperatures and TIPT/TEOS concentrations. Decomposition of TIPT alone at temperatures above 400$\^{C}$ produced porous crystalline TiO$_2$ films and they were not H7-selective. Decomposition of TEOS produced H$_2$-permeable SiO$_2$ films at 400-600$\^{C}$ but film deposition rate was very low. Addition of TIFT to the TEOS stream significantly accelerated the deposition rate and produced highly H$_2$-selective films. Increasing the TIPT/TEOS concentration ratio increased the deposition rate. The TiO$_2$/SiO$_2$ membranes formed at 600 $\^{C}$ have the permeation properties comparable to those of SiO$_2$ membranes produced from TEOS.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.4
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• pp.239-252
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• 1993

This study was done to analyze phonetic dysfunction and the effect of orthognathic surgery to phonation in the patients of mandibular prognathism. 20 persons were chosen as normal group and 20 patients of mandibular prognathism as abnormal for this study. 5 vowel sounds-'ㅏ(a)', 'ㅔ(e)', 'ㅣ(i)', 'ㅗ(o)', 'ㅜ(u)' and 14 consonant sounds-'ㄱ(g)', "ㄴ(n), 'ㄷ(d)', 'ㄹ(l)', 'ㅁ(m)', 'ㅂ(b)', 'ㅅ(s)', 'ㅇ(ng)', 'ㅈ(j)', 'ㅊ(ch)', 'ㅋ(k)', 'ㅌ(t)', 'ㅍ(p)', 'ㅎ(h)', were checked. We recorded these sounds in the period of preopration, postop. 12 months, postop. 24 months. A Formant ratio and a length of consonant time were studied with discriminant analysis. As a result of the study, the following conclusion were gained. 1. As a result of the analysis on vowel dysfunction patiensts of mandibular prognathism, more than 80% of men patients showed the dysfunction in prelingual sound 'ㅔ(e)' and 'ㅣ(i)'. More than 70% of women patients showed the dysfunction in all vowel. 2. One year later from the orthognathic surgery, men patients showed a marked improvement in 'ㅏ(a)'. The next were 'ㅗ(o)', 'ㅜ(u)' and 'ㅣ(i)'. Women patients showed a marked improvement in 'ㅜ(u)'. 3. Two year later from the orthognathic surgery, men patients showed a marked improvement in prelingual sound 'ㅔ(e)' and postlingual sound 'ㅗ(o)'. Women patients showed a marked improvement in 'ㅏ(a)'. More than 20% of patients showed the phonetic improvement compared with the condition of the postop. 12 months. 4. As a result of the analysis on consonant dysfunction patient of mandibular prognathism. more than 80% of men patients showed the dysfunction in lingual sound 'ㅅ(s)'. Most women patients showed the dysfunction in labial sound 'ㅁ(m)' and lingual sound 'ㄴ(n)'. More than 50% of patients showed the dysfunction in labial sound and lingual sound. 5. One year later from the orthognathic surgery. men patients showed a complete improvement in hard palatal sound 'ㅈ(j)'. The next were labial sound 'ㅂ(b)', lingual sound 'ㅅ(s)', soft palatal sound 'ㄱ(g)' and 'ㅋ(k)'. Women patients showed a marked improvement in soft palatal sound 'ㅇ(ng)' and 'ㄱ(g)'. 6. Two year later from the orthognathic surgery, all patients showed remarkable improvement in consonant sounds. except for labial sound 'ㅁ(m)', 'ㅍ(p)' and lingual sound 'ㄴ(n)'. The improvement ratio was increased as the time was going on compared with the condition of postop 12 months.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.183-187
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• 1983

The investigate the varietal differences is physiological characteristics related to nutrient uptake and response to nitrogen and phosphorus, a pot experiment was conducted in a temperature control chamber. Three varieties with different cold resistances were grown under normal ($23^{\circ}-25^{\circ}C$) and cold ($15^{\circ}C$) conditions with three nitrogen and phosphorus application levels. The cold temperature was treated for twelve days after thirty days from seeding. The results were summarized as follows: 1. Dry weight and nutrient contents were reduced in cold temperature treatment compared with control and the reduced ratio by low temperature were in order of dry weight 29.4% $P_2O_5$ 21.3%, N 15.3%, $K_2O$ 10.1%, $SiO_2$ 8.7%. 2. The reduced ratio of phosphorus contents of each varieties to normal condition were 13.5% in resistant, 19.5% in medium, 31.1% in susceptible variety, respectively. 3. The phosphorus and silicate contents of plants showed a good relationship with varietal differences in cold resistance but nitrogen and potassium didn't showed, therefore, phosphorus and silicate contents might be used as the index for physiological characteristics related with cold resistance. 4. Phosphorus content slightly increased with nitrogen application but silicate content decreased. Upon phosphorus application, nitrogen and silicate contents were increased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.1-7
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• 1980

In 1976, a newly released rice variety, Yushin, was planted in 300,000 ha of the 533,000 ha of cultivated total hecterage with new rice varieties. High productivity and quality were achieved by farmers around country. However, the wilting phenomena of Yushin occured in some regions where were employed poor cultural management, and flowed sewage into the paddy field from industrial factories. This study was identified some factors for the wilting phenomena of Yushin rice variety in morphological and physiological aspects. The Yushin variety showed greater internode elongation on low part of the stems that close related to lodge at heavier nitrogen levels, excessive number of spikelets per unit leaf blade weight i.e. higher sink/source ratio, and greater consumption of respiratory substrate by increased respiration rate of rice plant as compared with those of Tongil rice variety. In physilogical aspects, the Yushin variety was significantly declined root development and root activities under heavy nitrogen conditions. Yushin rice variety was decreased $K_2$O/N ratio, carbohydrate content in stem of rice plant, and physiological root activities specially in low light intensity, 50% light interception plots. Therefore, above factors were mainly promoted the wilting phenomena of Yushin rice variety.

• Journal of ILASS-Korea
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• v.25 no.1
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• pp.21-26
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• 2020

The objective of this work is to numerically reveal the effect of equivalence ratio change on the simultaneous reduction of NO_X and soot emissions from the simulated-EGR compression ignition engine containing CO₂. An experiment was conducted by using a single-cylinder common-rail injection system engine, an intake control system, and exhaust emissions analyzers. The numerical analysis results were validated under the same experimental conditions. To investigate the effect of equivalence ratio by simulated-EGR containing CO₂, the O₂, N₂, and CO₂ mole fraction were changed in the initial air conditions to the cylinder. The results were analyzed in terms of peak cylinder pressure, indicated mean effective pressure, indicated specific nitrogen oxide, and indicated specific soot. It was revealed that ignition delay characteristics and heat release rate (ROHR) characteristics were not significantly different according to the equivalence ratio. However, as the equivalence ratio increased from 0.68 to 0.83, the maximum combustion pressure and IMEP decreased by about 6.5% and 9.4%, respectively. In the case of ISFC, as is well known, the trend is opposite of IMEP. In the case of ISNO, as the equivalence ratio increased, less NO was generated, and as the equivalence ratio increased by 0.05, the ISSoot value of about 10% increased.