• The Korean Journal of Pain
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• 제25권3호
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• pp.151-154
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• 2012

Background: The aim of this study was to document the optimal spacing of two cannulae to form continuous strip lesions and maximal surface area by using water-cooled bipolar radiofrequency technology. Methods: Two water-cooled needle probes (15 cm length, 18-gauge probe with 6 mm electrode tip) were placed in a parallel position 10, 20, 24, 26, and 28 mm apart and submerged in egg white. Temperatures of the probes were raised from $35^{\circ}C$ to $90^{\circ}C$ and the progress of lesion formation was photographed every 1 minute with the increase of the tip temperature. Approximately 30 photographs were taken. The resultant surface areas of the lesions were measured with the digital image program. Results: Continuous strip lesions were formed when the cannulae were spaced 24 mm or less apart; monopolar lesions around each cannula resulted if they were spaced more than 26 mm apart. Maximal surface areas through the formation of continuous strip lesion were 221 $mm^2$, 375 $mm^2$, and 476 $mm^2$ in 10, 20, and 24 mm, respectively. Summations of maximal surface area of each monopolar lesions were 394 $mm^2$ and 103 $mm^2$ in 26 and 28 mm, respectively. Conclusions: Water-cooled bipolar Radiofrequency technology creates continuous "strip" lesions proportional in size to the distance between the probes till the distance between cannulae is 24 mm or less. Spacing the cannulae 24 mm apart and treating about $80^{\circ}C$ for 24 minutes maximizes the surface area of the lesion.

• 전기학회논문지
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• 제56권3호
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• pp.561-565
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• 2007

We propose glass and PDMS (polydimethylsiloxane) chips for DNA amplification with continuous-flow PCR (polymerase chain reaction). The PDMS microchannel was fabricated using a negative molding method for sample injection. Three heaters and sensors of ITO (indium-tin-oxide) thin films were fabricated on glass chip. ITO heaters and sensors were calibrated accurately for the temperature control of the liquid flow. ITO heater generated stable heat versus applied power. ITO sensor resistance was changed linearly versus temperature increase as a RTD (resistance temperature detector) sensor. As a result, we enable precision temperature control of continuous-flow PCR chip. Using the continuous-flow PCR chip DNA plasmid pKS-GFP 720 bp was successfully amplified.

• 한국분말재료학회지
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• 제15권3호
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• pp.204-209
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• 2008

Aluminum alloys are not only lightweight materials, but also have excellent thermal conductivity, electrical conductivity and workability, hence, they are widely used in industry. It is important to control and enhance the densification behavior of metal powders of aluminum. Investigation on the extrusion processing combined with equal channel angular pressing for densification of aluminum powders was performed in order to develop a continuous production process. The continuous processing achieved high effective strain and full relative density at $200^{\circ}C$. Optimum processing conditions were suggested for good mechanical properties. The results of this simulation helped to understand the distribution of relative density and effective strain.

• 한국미생물·생명공학회지
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• 제19권1호
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• pp.70-75
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• 1991

Continuous and simultaneous production of gluconic acid and sorbitol from glucose and fructose was carried out by using glucose-fructose oxidoreductase and glucanolactonase of Zymomonas mobilis. In order to utilize the enzymes without purification, Zymomonas mobilis was permeabilized with toluene. Optimum conditions for permeabilization and reaction kinetics of permeabilized Zymomonas mobilis were studied. In batch operation with the permeabilized cells immobilized in alginate beads, about 90% conversion was obtained within 35 h reaction. Continuous production of gluconic acid and sorbitol using the immobilized permeabilized cells was carried out. Optimum conditions for continuous operation with the imn~obilized cells were; pH 6.2 and temperature $40^{\circ}C$. Maximum productivities for gluconic acid and sorbitol were about 14.5 g/l/h and 14.8 g/l/h respectively at the dilution rate of 0.075 $h^{-1}$ when 300 g/l each of substrates was fed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.261-263
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• 1995

The continuous sliding mode controller with disturbance observer for the tracking control of permanent magnet synchronous motor(PMSM) is presented. In spite of the robust performance of variable structure control, there exists an undesirable chattering problem, which may be very harmful in some cases. To alleviate the problem, continuous sliding mode controller with continuous saturation function is proposed and also the prescribed performance can be obtained by efficient compensation of disturbance. Experimental results using 7.5 kW, 4000 rpm motor which is controlled by TMS320C30 DSP, are shown to demonstrate the usefulness of the proposed algorithm.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2002년도 전력전자학술대회 논문집
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• pp.715-718
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• 2002

As the modern technology of continuous casting plant is focused on improvement of slab quality, the control system of strand driven roll which has positive effect is investigated in this paper. An irregular distribution of withdrawal force gives rise to horizontal crack in high and middle grade carbon steel. Based on the basic understanding on design concept of high technology company, monitoring the withdrawal force distribution of strand driven roll and analysis of the control system was Performed at continuous casters of POSCO. The control algorithm of withdrawal force distribution for A.C motor vector control, which was derived from above study and had been applied for POSCO Kwangyang 1-4 continuous casting plant, is presented.

• 한국농공학회지
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• 제42권
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• pp.61-67
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• 2000

Composting of hog manure amended with sawdust trials lasted three weeks and used pilot-scale in bin composting system. Results showed that the rise temperature and carbon dioxide evolution in compost during the composting decomposition process were affected by the aeration method, pH, C/N, moisture content, bulk density and particle size distribution. No significant differences existed in biophysical properties of the composit produced from the continuous and intermittent aeration method. The intermittent aeration was very successful in compost odor control and required less time to reach stability than the continuous aeration.

• 조명전기설비학회논문지
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• 제30권2호
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• pp.20-25
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• 2016

This paper describes the effectiveness of continuous water removal in oil immersed transformers. Insulation oil in which insulation papers were immersed were prepared for tests and water concentrations in oil with heating time were measured at five oil temperatures. Also, the tests that water dissolved in $100^{\circ}C$ oil was removed at once and continuously at $50^{\circ}C$ and $100^{\circ}C$ were performed for consideration of effective method for water removal. Test results indicated that the oils for water measurement have to be extracted at similar temperatures and water in oil has to be continuously removed at higher temperatures for more effective water management of transformers.

• Kyungpook Mathematical Journal
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• 제48권3호
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• pp.487-493
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• 2008

A. Di Nola & S.Sessa [8] showed that two compact spaces X and Y are homeomorphic iff the MV -algebras C(X, I) and C(Y, I) of continuous functions defined on X and Y respectively are isomorphic. And they proved that A is a semisimple MV -algebra iff A is a subalgebra of C(X) for some compact Hausdorff space X. In this paper, firstly by use of functorial argument, we show these characterization theorems. Furthermore we obtain some other functorial results between topological spaces and MV -algebras. Secondly as a classical problem, we find a necessary and sufficient condition on a given residuated l-monoid that it is segmenently embedded into an l-group with order unit.

• 한국환경과학회지
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• 제8권4호
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• pp.443-449
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• 1999

This paper describe the working of algal culture system under batch and continuous feeding effluents in biological treatment process. The main objective of this study was the determination of fundamental opeating parameters such as dilution rates, light intensity, biomass concentration, nutrients contents, which engender an effective nutrient and organic waste removal process. The results of this research indicate that the algae system will remove effectively nutrient and organic waste. In batch cultures, 91.8% dissolved orthophosphate and 83.3% ammonia nitrogen were removed from the sewage in ten days. In continuous flow systems, a detention time of 2.5 days was found adequate to remove 91% T-P, 87% T-N and 95% $NH_3-N$. At 22-28$^{\circ}C$, 60 rpm, with an intensity of 3500 Lux, the specific growth rate, k was 0.59/day in batch experiments. The optimal growth temperature and nutrients rate (N/P) were respectively $25^{\circ}C$ and 3~5. With an abundant supply of untrients, it was possible to sustain substantial population densities in the temperature range of 22~28$^{\circ}C$.