• Geomechanics and Engineering
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• v.31 no.6
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• pp. 583-597
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• 2022

Frost heave can cause uneven ground uplift that may damage geo-infrastructure. To assist damage-prevention strategies, standard frost heave testing methods and frost susceptibility criteria have been established and used in various countries. ASTM International standard testing method is potentially the most useful standard, as abundant experimental data have been acquired through its use. ASTM International provides detailed recommendations, but the method is expensive and laborious because of the complex testing procedure requiring a freezing chamber. A simple frost heave testing method using a temperature-controllable cell has been proposed to overcome these difficulties, but it has not yet been established whether a temperature-controllable cell can adequately replace the ASTM International recommended apparatus. This paper reviews the applicability of the ASTM International testing method using the temperature-controllable cell. Freezing tests are compared using various soil mixtures with and without delivering blow to depress the freezing point (as recommended by ASTM International), and it is established that delivering blow does not affect heave rate, which is the key parameter in successful characterization of frost susceptibility. As the freezing temperature decreases, the duration of supercooling of pore water shortens or is eliminated; i.e., thermal shock with a sufficiently low freezing temperature can minimize or possibly eliminate supercooling.

• Macromolecular Research
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• v.16 no.6
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• pp.544-548
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• 2008

An HPLC column with a self-contained temperature control device was constructed for preparative temperature programmed interaction chromatography. Two Peltier plates were attached to a large bore column ($120{\times}22\;mm$ i.d.) and the column temperature was controlled by PID mode feed back control. At a flow rate of 1.5 mL/min, the column temperature could be increased and decreased at a rate as high as $50^{\circ}C/min$ and $10^{\circ}C/min$, respectively, which is much faster than using a column jacket and bath/circulator. The rapid heating and cooling rates allows a high repetition rate of chromatographic fractionation. The performance of the temperature controllable column was demonstrated successfully by the fractionation of homo-polymer precursors from diblock copolymers.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.177-180
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• 2001

A saw-tooth waveform generator with current-controllable frequency is described. The generator utilizes operational transconductance amplifiers as switching element. It features simple and wide sweep capability. The circuit built with commercially avaliable components exhibits good linearity of current to frequency and relatively low temperature sensitivity.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.3
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• pp.167-172
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• 1999

The device characteristics of the base resistance controlled thyristor with self-align corrugated p-base is demonstrated for the first time with varying the n+ cathode width and the temperature form room temperature to $125^{\circ}C$. The experimental results show that the snap-back in the CB-BRT is significantly suppressed irrespective of the various n+ cathode width and the temperature as compared with that of the conventional BRT. The maximum controllable current of the CB-BRT is uniformly higher when compared with that of the conventional BRT over the temperature range from room temperature to $125^{\circ}C$.

• Journal of electromagnetic engineering and science
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• v.14 no.3
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• pp.267-272
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• 2014

Hyperthermia is a form of cancer treatment in which affected human tissue is exposed to $>40^{\circ}C$ temperature. In this paper, our goal is to assess the efficacy of fullerene agents to reduce heating time for cancer treatment. Such agents can accelerate heating of cancer cells and improve hyperthermia treatment efficacy. Typically, in vitro testing involves cancer cell culturing, heating cell cultures in accordance to specifications, and recording cancer cell viability after hyperthermia. To heat cell cultures, we design and evaluate a 2.4-GHz microwave cavity with controllable temperature. The cavity is comprised of a polystyrene cell culture dish (diameter = 54 mm, height = 13.5 mm) and a printed monopole antenna placed within the cavity for microwave heating. The culture temperature can be controlled through the intensity and duration of the antenna's microwave radiation. Heating experiments were carried out to validate the cavity's performance for F-12K culture medium (Kaighn's F-12K medium, ATCC). Importantly, fullerene agents were shown to reduce heating time and improve hyperthermia treatment efficacy. The culture medium temperature increased, on average, from $24.0^{\circ}C$ to $50.9^{\circ}C$ (without fullerene) and from $24.0^{\circ}C$ to $56.8^{\circ}C$ (with 3 mg/mL fullerene) within 15 minutes.

• Journal of Aerospace System Engineering
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• v.6 no.4
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• pp.24-28
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• 2012

In this paper, 2-D experiment and steady-state computational fluid analysis were conducted for measuring the hear transfer coefficient of pintle type controllable thruster in high pressure and temperature. In case of 2-D experiment, transient liquid crystal technique was used for measuring heat transfer coefficient for the 2-D pintle model. The experimental result was used to validate the CFD result. The CFD results well predicted the heat transfer coefficient on the pintle surface except the nozzle downstream region, where the results by CFD was higher than experimental results. The CFD results were also compared with the result by Bartz equation and the it was shown that the Bartz equation overestimated the heat transfer coefficient on the nozzle throat as much as 80%.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.13-19
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• 1995

In order to produce phenylalanine without tyrosine co-production, we constructed various temperature-controllable expression vectors by insertion of lower expression of the tyrA gene into the plasmid pSY130-14. And tyrosine revertant to cultivate without addition of tyrosine, was selected from Escherichia coli strain AT2471[tyrA , thi ] by spontaneous mutation. The strain AT2471 harbouring plasmid pSY146A and the tyrosine revertant 5 harbouring plasmid pSY111-14 produced 12 g/l and 15 g/l of phenylalanine respectively in a 2.5 l jar fermenter at a constant temperature of $39^{\circ}C$ after 55 hours cultivation.

• Proceedings of the KIEE Conference
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• 2003.10a
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• pp.45-48
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• 2003

In the research of proteomics, mass spectrometry analysis is the essential method for identification of the unknown proteins. Trypsin treatment for the sample preparation of mass spectrometry is the inevitable procedure[1]. However, sample preparation procedure is cumbersome and time consuming. To resolve these problems, Temperature controllable microreactor was designed and fabricated. It consists of metering chamber, micro channel, reaction chamber, platinum (Pt) thin film heater and a temperature sensor so that micro metering and mixture of reagent with temperature control can be done on the same chip. The total size of the fabricated microreactor was $37{\times}30{\times}1\;mm^3$ and the size of channel cross section was $200{\times}100{\mu}m^2$. PID temperature controller was realized using NI DAQ, PCI-MIO-l6E-1 board and LabVIEW program.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.5
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• pp.1-14
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• 2014

This study has found out appropriate scopes of correlated color temperature and illuminance value with regard to general diffused lighting and work in the kitchen. It also has presented appropriate photometric quantity control speed for behavioral change with the following results. 1)For general diffused lighting, the appropriate photometric quantity has turned out to be 4,000 to 4,500K in color temperature and illuminance value of 300 to 400lx. And 300lx at 4,500K has proven to be the most comfortable, behavior-appropriate, and preferred pair. 2)As far as appropriate photometric quantity for work is concerned, color temperature of 4,000 to 5,000K and illuminance value of 600 to 800lx are appropriate, while 700lx at 4,500 to 5,000K are the most comfortable, behavior-appropriate, and preferred set. 3)As for appropriate photometric quantity control speed in behavioral change, 3 to 5 seconds has proven the most comfortable, appropriate, and preferred for behavioral change from entry to general areas and 1 to 3 seconds for change from general to work.

• 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.