• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1134-1139
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• 2004

Recently, development of flame control scheme has been hot issues in the combustion engineering. It has been held that flame shape can be controllable by pressure inside combustor. The influence of combustor atmospheric pressure on flame shape was investigated in the present study. The flame shape, flammable limit, flame temperature and nitric oxide emission were measured as functions of combustor atmospheric pressure and equivalence ratio. The reaction region became longer and wider with decreasing combustor atmospheric pressure by direct photography, hence reduction of blow off limit. This tendency was also observed in the mean flame temperature distribution. Nitric oxide emission decreased with decreasing combustor atmospheric pressure. Low NOx combustion is ascribed to wide-spread reaction region in the low atmospheric pressure condition. These results demonstrate that flame shape and nitric oxide emission can be controllable with combustor atmospheric pressure.

• Textile Coloration and Finishing
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• v.5 no.2
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• pp.134-138
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• 1993

Wool, silk and nylon 6 fabrics were treated with low-temperature plasma under atmospheric pressure of acetone/argon or helium/argon for 30 and 180 sec, and then dyed with leveling type acid dye, C.I. Acid Red 18 and milling type acid dye, C.I. Acid Blue 83. In spite of short time of the plasma treatment for thirty seconds, the color depth of wool fabrics was increased remarkably with both of the plasma gases, aceton/argon or helium/argon and with the kinds of dyes i.e., levelin type or milling type. But the atmosperic low-temperature plasmas did not increase the depth of silk and nylon 6 fabrics dyed with both of the acid dyes regardless of the teated time and plasma gases. It seems that low-temperature plasma by atmospheric-pressure discharge is effective for improvement of dyeing of wools as is the same way with the low-temperature plasma by glow discharge. The kinds of plasma gases and treated time did not influnce the depth of wool fabric pretreted with the atmosperic low-temperature plasmas.

• Atmosphere
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• v.19 no.1
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• pp.67-78
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• 2009

A strong negative correlation has been detected between the North Pacific Oscillation Index (NPI) and the Effective Drought Index (EDI) in May over Korea. In May of positive NPI year, anomalous patterns caused a drought in Korea as follows: the anomalous south-low, north-high low-level pressure patterns in the northeast and southeast of Korea have strengthened the anomalous northerlies to Korea. In addition, these anomalous northerlies have prevented western North Pacific (WNP) high from moving northward. As a result, anomalous descending flows have strengthened in the mid-latitude region in East Asia. In the WNP, the anomalous south-high, north-low sea surface temperature (SST) has been widely distributed, which has strengthened anomalous south-low, north-high low-level pressure patterns. These anomalous characteristics of pressure and SST patterns observed in May of positive NPI years have already been detected in previous winter (December-February) and early spring (March, April). In addition, the anomalous negative sea ice concentration in the North Pacific during two seasons has strengthened the anomalous anticyclonic circulation in the same region and in turn made a contribution to formation of anomalous south-low, north-high pressure patterns in May.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.8
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• pp.12-16
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• 2002

It is confirmed that the ITO(Indium Tin Oxide) thin films can be etched by low-temperature plasma at atmospheric pressure. The etching happened deepest at a hydrogen flow rate of 4 sccm, and the etch rate was 120 /min. The etching speed corresponded to the H$\alpha$* emission intensity The etching mechanism of the ITO thin films is as follows; thin films were reduced by H$\alpha$*, and the metal compound residues were detached from the substrate by reacting on the CH* The etching was started after etching time of initial 50 sec and above the threshold temperature of 145$^{\circ}C$. The activation energy of 0.16 eV(3.75 Kcal/mole) was obtained from the Arrehenius plots.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.974-983
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• 1997

The Okhotsk Sea is unique natural object with climatic peculiarities. The climate of the Okhotsk Sea results from the general distribution of solar radiation during a year, and the characteristics of the atmospheric circulation that varies through a year: In cold half year the main pressure formations are Siberian high and Aleutian low. Asian low centered on Afghanistan dominates over the Asian continent in summer. The North-Pacific sea surface is under effect of permanent North Pacific high. The changes in their position from year to year are very significant. The anticyclonic activity over the Far Eastern Seas is one of the main factors for the formation of weather anomalies over the adjacent territories. The analysis of summer weather characteristics over the coast of Okhotsk and East Sea using the data obtained from Hydrometeorological stations during $1949\~1990$ showed that, to a great extent, distribution of the air temperature depends on thermal state of the Okhotsk Sea and atmospheric circulation over it. We show some relations between weather characteristics and the intensity of atmospheric action center for the North Pacific high in summer when its ridge propagates to Okhotsk Sea. Correlation coefficients between air pressure over the Okhotsk Sea and air temperature for the coastal areas reach up to 0.7. Analysis of the spatial-temporal distribution of main meteorological values over the Okhotsk Sea such as air pressure, and air temperature are also performed.

• Journal of Korean Society for Atmospheric Environment
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• v.5 no.1
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• pp.52-61
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• 1989

The hydrodenitrogenation of quinoline dissolved in n-heptane was studied over sulfided Ni-Mo/$\gamma-Al_2O_3$ catalyst at the range of the temperature between 553 K and 673 and the total pressure between $20 \times 10^5$ Pa and $60 \times 10^5$ Pa in a fixed bed flow reactor. Quinoline conversion was very high at relatively low temperature and total pressure, and decreased with quinoline partial pressure. The thermodynamic equilibrium between quinoline and Py-THQ existed in wide ranges of experimental conditions and shifted in favor of quinoline at higher temperature. At the range of the temperature betwwen 553 K and 673 K and at the total pressure $60 \times 10^5$ Pa, the quinoline reaction rate was 1st order with respect to the concentr4ation of quinoline and its apparent activation energy was 7.15 Kcal/mole.

• Korean Journal of Remote Sensing
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• v.16 no.2
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• pp.117-133
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• 2000

We studied the sea level variations at Kerguelen island in the South Indian Ocean with ARGOS data and meteorological data during about 1 year(May 1993~April 1994) through using filter, spectral analysis, coherency and phase, and found characteristics for the two oceanic signal levels(detided oceanic signal level, h$_{detided}$ and seasonal oceanic level, h$_{corr.ib}$). The forms of atmospheric pressure variations are good agreed to between ARGOS data and meteorological data in the observed periods. This Kerguelen area shows the inflow of an air temperature(gain of a radiant heat) into the sea water and the stagnation of high atmospheric pressure bands in summer, and the outflow of a sea water temperature(loss of sensible and latent heat) toward the atmosphere and the stagnation of low atmospheric pressure bands in winter. The seasonal difference of sea level between summer and winter is about 1.6cm. Both the detided oceanic signal level(h$_{detided}$) variation and the inverted barometer level(h$_{ib}$) variation have a strong correlation for T>1day period bands. The characteristics of h$_{detided}$ variation are not decided by the influence of any meteorological distributions (atmospheric pressure), but the influence of other factors(bottom water temperature) for T>2days periods bands. h$_{corr.ib}$ plays a very important role of sea level variation in the observed periods (especially T>about 180days period bands).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.5
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• pp.344-349
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• 2020

Modern thin film deposition processes require high deposition rates, low costs, and high-quality films. Atmospheric pressure plasma-enhanced chemical vapor deposition (AP-PECVD) meets these requirements. AP-PECVD causes little damage on thin film deposition surfaces compared to conventional PECVD. Moreover, a higher deposition rate is expected due to the surface heating effect of atomic hydrogens in AP-PECVD. In this study, polycrystalline silicon thin film was deposited at a low temperature of 100℃ and then AP-PECVD experiments were performed with various plasma powers and hydrogen gas flow rates. A deposition rate of 15.2 nm/s was obtained at the VHF power of 400 W. In addition, a metal foam showerhead was employed for uniform gas supply, which provided a significant improvement in the thickness uniformity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.4
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• pp.486-492
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• 2016

This study investigates the relationship between environmental factors, such as semilunar rhythm and atmospheric pressure, and the release of Marphysa sanguinea larvae. During artificial seed production in a temperature-regulated culture system, there was an increase in the number of released larvae at tide times between 3-4 and 9-11. Numbers of larvae released were significantly correlated with tidal rhythms. Atmospheric pressure also appeared to influence larval release, with increased numbers released when a period of high atmospheric pressure followed a period of low pressure.

• Journal of the Korean Ceramic Society
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• v.39 no.4
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• pp.409-412
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• 2002

Under atmospheric pressure, apparently homogeneous and stable plasma can be generated from insulator barrier rf plasma generators each of which has an rf powered cathode and a grounded anode covered with a dielectric insulating material. In order to characterize the generating plasma under atmospheric pressure, some basic characteristic have been evaluated by the Langmuire probe method as well as by optical emission spectroscopy. From the result of plasma characteristics, the generated plasma was verified to be nonequilibrium; T(electron)>T(excitation)>T(gas). High rate Si(100) etching (($1.5{\mu}m$/min) were achieved by using He plasma containing a small amount of $CF_4$.