• Journal of Environmental Science International
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• v.16 no.8
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• pp.907-912
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• 2007

Ion exchange resin was used to remove silica ion at ultralow concentration. The effects of temperature, type of ion exchange resin and single/mixed-resin systems on removal efficiency were estimated. As temperature increased, the slope of concentration profile became stiff, and the equilibrium concentration was higher. In the single resin system, the removal of silica was continued up to 400 min, but the silica concentration was recovered to initial concentration after 400 min due to the effect of dissolved $CO_2$. In the mixed-resin system it took about 600 min to reach equilibrium. Because of faster cation exchange reaction than anion exchange reaction, the effect of $CO_2$ could be removed. Based on the experimental results carried out in the mixed-resin system, the selectivity coefficients of silica ion for each ion exchange resin were calculated at some specific temperatures. The temperature dependency of the selectivity coefficient was expressed by the equation of Kraus-Raridon type.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.559-562
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• 2004

A 2.2-inch QCIF+ $(176{\times}RGB{\times}220)$ TFT-LCD with integrated row driver was developed using a standard amorphous silicon TFT technology. At low temperature $({\sim}-20^{\circ}C)$, the integrated row driver operation is dramatically effected by the electron drift mobility variation $({\sim}50%)$ and the threshold voltage shift $({\sim}1V)$ of the a-Si TFT. We studied the temperature dependency of the circuit design and found that higher on-current circuit is important to guarantee good operation in wide temperature range.

• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.418-420
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• 2005

This paper proposed ultrasonic distance measurement module development for correct distance detection with collision escaping or obstacle of mobile robot is traveling self-regulation. Representative ultrasonic module applied in existing was Polaroid company's 6500 series and Devantech company's SRF04/SRF08 series. This ultrasonic sensors are corrupted by systematic errors due mainly to the dependency of sound speed upon surrounding conditions and random errors of uncertain origin. Therefore Ultrasonic distance detecting means of error compensation method and high definition, narrow beam angle, board area distance detecting means to apply to ultrasonic mobile robot control urgently need. In this paper use internal type temperature compensation method to improve problem of ultrasonic distance measurement method instead of that volume that have shortcoming of used correct temperature compensation methods applied big addition device. Compensate error by environment change of temperature. Humidity density etc. and is applicable to mobile robot offering various interface and real-time processing developed possible distance measurement module.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1315-1320
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• 2003

The thermal expansion coefficient, which causes the micro failure at the interfacial state of thin films is necessary to consider for proper designing MEMS. The effect of temperature on the coefficient of thermal expansion(CTE) of $SiO_2$ and $Si_3N_4$ film was investigated. Thermal strain induced by mismatch of CTE between substrate and thin film continuously measured with resolution-improved electronic speckle pattern interferometry(ESPI). The thermal stress induced by mismatch of CTE derivate through thermal strain. The thermal expansion coefficients of thin film were calculated with the general equation of CTE and thermal stress in thin films, and it confirmed that CTE of $SiO_2$changed from $0.25{\times}10^{-6}/^{\circ}C$ to $1.4{\times}10^{-6}/^{\circ}C$ with temperature increasing from 50 to $600^{\circ}C$

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.8
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• pp.448-455
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• 2009

A performance analysis of the regenerative gas turbine system with afterfogging is carried out. Because of the high temperature at the outlet of air compressor, afterfogging has a potential of improved recuperation of exhaust heat than inlet fogging. Thermodynamic analysis model of the gas turbine system is developed by using an ideal gas assumption. Using the model, the effects of pressure ratio, water injection ratio, and ambient temperature are investigated parametrically on thermal efficiency and specific power of the cycle. The dependency of pressure ratio giving peak thermal efficiency is also investigated. The results of numerical computation for the typical cases show that the regenerative gas turbine system with afterfogging can make a notable enhancement of thermal efficiency and specific power. In addition, the peak thermal efficiency is shown to decrease almost linearly with ambient temperature.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1145-1150
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• 2003

Zr-based bulk metallic glasses have a significant mechanical properties such as high strength and elastic strain limit, and a good processing ability due to the deformation behavior such as superplasticity under supercooled liquid region. Recently, many researches on the determination of optimum working condition in various bulk metallic glasses have been carried out. In this study, the deformation behavior and forming conditions of $Zr_{55}Cu_{30}Al_{10}Ni_{5}$ bulk metallic glass were investigated under three different strain rates and at various temperatures between 627K and 727K. The glass transition temperature, crystallization temperature and supercooled liquid region of $Zr_{55}Cu_{30}Al_{10}Ni_{5}$ bulk metallic glass are 680K, 762K and 82K, respectively.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.515-519
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• 1987

The kinetics of thermal softening of chinese cabbage was investigated by puncture tests with an Instron. It was concluded that low temperature-long time blanching and pasteurization process provided an opportunity of improving the texture of pasteurized Kimchi. The rate of softening showed apparent first order kinetics, and the apparent Arrhenius activation energies ranged from 2.8-42.4 kcal/mol. The temperature dependency of the softening rate during pasteurization was more profound by blanching at blanching at higher temperature.

• Environmental Engineering Research
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• v.24 no.4
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• pp.529-542
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• 2019

Nowadays, drying methods for municipal solid waste quality improvement have been adopted in the developed and developing countries to valorize wastes for a renewable energy source, reduce dependency on fossil fuel and keep safer disposal at landfills. Among them, biodrying, biostabilization, thermal drying and solar drying are the most common. Drying of municipal solid waste could offer several environmental and economic benefits. Therefore, this review highlighted the drying methods for municipal solid waste quality improvement around the world and compared them based on the reduction of moisture, weight and volume of municipal solid wastes against drying temperature and time by using statistical analysis. It was observed that the drying temperature of different drying methods accounted for 115 ± 40℃ for thermal drying, 59 ± 37℃ for solar drying, 55 ± 15℃ for biodrying and 58 ± 11℃ for biostabilization. Among the drying methods, thermal drying provided the shortest drying time. The moisture reduction, weight reduction, volume reduction and heating value increase of municipal solid waste could vary with drying temperature and time. Finally, the benefits and drawbacks of different drying methods were specified, and recommendations were made for the future efficient drying.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.225-230
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• 2008

Onion slices were dehydrated in a single layer at drying air temperatures ranging from $50{\sim}70^{\circ}C$ in a laboratory scale convective hot-air dryer at an air velocity of 0.66 m/s. The effect of drying air temperature on the drying kinetic characteristics were determined. It was found that onion slices would dry within $210{\sim}460\;min$ under these drying conditions. Moisture transfer during dehydration was described by applying the Fick's diffusion model and the effective diffusivity changed between $1.345{\times}10^{-8}$ and $2.658{\times}10^{-8}\;m^2/s$. A non-linear regression procedure was used to fit 9 thin layer drying models available in the literature to the experimental drying curves. The Logarithmic model provided a better fit to the experimental drying data as compared to other models. Temperature dependency of the effective diffusivity during the hot-air drying process obeyed the Arrhenius relationship with estimated activation energy being 31.36 kJ/mol. The effect of the drying air temperature on the drying model constants and coefficients were also determined.

• Industry Promotion Research
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• v.1 no.2
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• pp.13-17
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• 2016

ZTO films were annealed in a vaccum atmosphere conditions to research the temperature dependency of current-voltage characteristics. The ZTO film annealed in a vacuum became an amorphous structure but films annealed in an atmosphere condition had a crystal structure. The defects or depletion layer were formed by the electron-hole combination after annealing processes, and the electrical properties were changed depending on the crystal structure, binding energy and the variation of carriers. ZTO became more crystal-structural with increasing the annealing temperature, and the current increased at ZTO film annealed at $150^{\circ}C$ with Schottky contact.