• Journal of the Korean Society of Mechanical Technology
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• v.13 no.2
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• pp.55-61
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• 2011

This study analyzed on the characteristics of temperature distribution in an active regeneration DPF using computer simulation. In order to verify the boundary condition of analysis, results of temperature distribution in DPF are compared between experimental and computer simulation. Using this boundary condition, temperature distribution and filter's durability in DPF analyzed according to various operating conditions. The results of computational analysis are agreed well with experimental ones from the tendency of temperature distribution of axis and radius direction. The temperature increases and the axial temperature gradients in DPF according to velocity of exhaust gas are lowered as the high velocity of exhaust gas. But the temperature gradients of radius direction at exit side in DPF are grown as the high velocity of exhaust gas. The results according to inlet temperature of exhaust gas show that the increase ratios of temperature in DPF are grown as the high temperature of exhaust gas.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.693-695
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• 2003

In this paper, we have investigated temperature-dependent characteristics of current-voltage for double gate MOSFET with main gate and side gate. DG MOSFET has the main gate length of 50nm and the side gate length of 70nm. We have investigated the temperature-dependent characteristics of current-voltage and drain voltage is changed from 0V to 5.0V at $V_{mg}$ =1.5V and $V_{sg}$ =3.0V. We have obtained a very good characteristics of current-voltage for 77K. We have simulated using ISE-TCAD tool for characteristics analysis of device.

• Advances in nano research
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• v.5 no.1
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• pp.61-67
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• 2017

A semi-empirical approach to model the temperature effects on I-V characteristics of Carbon Nanotube Field Effect Transistors (CNTFETs) is proposed. The model includes two thermal parameters describing CNTFET behaviour in terms of saturation drain current and threshold voltage, whose values are extracted from the simulated and trans-characteristics of the device in different temperature conditions. Our results are compared with those of a numerical model online available, obtaining I-V characteristics comparable but with a lower CPU calculation time.

• Journal of ILASS-Korea
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• v.15 no.2
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• pp.94-99
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• 2010

The object of this investigation is to study the thermal properties and spray characteristics of kerosene fuel in high temperature and pressure conditions. In order to investigate the thermal properties and spray characteristics, KIVA3 and SUPERTRAPP have been used at the same time. The thermal properties of kerosene has been calculated in high temperature and pressure condition using SUPERTRAPP. The study of spray characteristics has been conducted at both original properties of KIVA3 and calculated properties. The evaporation rate was increased in proportion to pressure when the calculated properties were used. However, the effect of pressure was not shown in the case of using original properties. So the calculated properties are more effective than original properties in high temperature and high pressure condition.

• Journal of the Korean Ceramic Society
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• v.26 no.1
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• pp.7-12
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• 1989

The effects of composition ratios and sintering conditions in Co1-xMgxO ceramics on the sintering characteristics, electrical properties and oxygen sensing characteristics were investigated. In the same sintering conditions, porosity decreased with increase of MgO contents. The relationshiop of temperature and resistance in Co1-xMgxO ceramics showed NTC(negative temperature coefficient) characteristics at the temperature range from $700^{\circ}C$ to 1,10$0^{\circ}C$. In the case of pure CoO, however, the PTC(positive temperature coefficient) characteristics were shown over about 90$0^{\circ}C$. The electrical conductivity of Co1-xMgxO ceramics decreased proportionally with decrease of oxygen partial pressure at the range from 1 to 10-4(atm). Particularly, Co0.5Mg0.5O ceramics showed the highest sensitivity to oxygen gas.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.82-84
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• 1993

A method for simulating general characteristics and temperature characteristics of magnetizing fixture coil of the capacitor discharge impulse magnetizer-magnetizing fixture system using SPICE is presented. This method has been developed which can aid the design, understanding and inexpensive, time-saving of magnetizing circuit. As the detailed characteristics of magnetizing circuit can be obtained, the efficient design of the magnetizing circuit which produce desired magnet will be possible using our SPICE modeling. Especially, The knowledge of the temperature of the magnetizing fixture is very important to forecast the characteristics of the magnetizing circuits tinder different conditions. The capacitor voltage was not raised above 810[V] to protect the magnetizing fixture from excessive heating. The temperature estimation method uses multi-lumped model with equivalent thermal resistance and thermal capacitance.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.4
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• pp.71-77
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• 1998

In this paper, algeration of electical characteristics is analyzed when the operating temperature of MOSFET, BJT and CMOS/BiCMOS inverter is lowered from 300K to 77K. As the operating temperature is lowered, electric characteristics of MOSFET are enhanced generally but, those of bipolar transistor are degraded because current gain is reduced by BGN(Band Gap Narrowing) effect. For the inverter considered in this work, switching characteristics of PSA-BiCMOS inverter are enhanced by the electrical characteristics enhancement of MOSFET when the operating temperature is reduced to 200K, while under 200K, those of PSA-BiCMOS inverter are degraded because the degradation of BJT impacts on the inverter circuit.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.10
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• pp.451-457
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• 2003

The silicon wafer is stable status at room temperature, but it is weak at high temperatures which is necessary for it to be fabricated into a power semiconductor device. During thermal diffusion processing, a high temperature produces a variety thermal stress to the wafer, resulting in device failure mode which can cause unwanted oxide charge or some defect. This disrupts the silicon crystal structure and permanently degrades the electrical and physical characteristics of the wafer. In this paper, the electrical characteristics of a single oxide layer due to high temperature diffusion process, wafer resistivity and thickness of polyback was researched. The oxide quality was examined through capacitance-voltage characteristics, defect density and BMD(Bulk Micro Defect) density. It will describe the capacitance-voltage characteristics of the single oxide layer by semiconductor process and device simulation.

• Korean Journal of Materials Research
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• v.25 no.7
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• pp.347-351
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• 2015

To study the characteristics of ZTO, which is made using a target mixed $ZnO:SnO_2=1:1$, the ZnO and $SnO_2$ were analyzed using PL, XRD patterns, and electrical properties. Resulting characteristics were compared with the electrical characteristics of ZnO, $SnO_2$, and ZTO. The electrical characteristics of ZTO were found to improve with increasing of the annealing temperature due to the high degree of crystal structures at high temperature. The crystal structure of $SnO_2$ was also found to increase with increasing temperatures. So, the structure of ZTO was found to be affected by the annealing temperature and the molecules of $SnO_2$; the optical property of ZTO was similar to that of ZnO. Among the ZTO films, ZTO annealed at the highest temperature showed the highest capacitance and Schottky contact.

• Journal of the Korean Society of Safety
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• v.29 no.3
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• pp.8-13
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• 2014

Accidents involving portable ranges occurred total 133 cases for the last five years(2008~2012). It accounted for 18.0% of all gas accidents(739 cases). Major causes of accidents are using of excessive hot grill, leaving a butane can near fire and overheating of a butane can during cooking. In this study, it is a desire to investigate the relationship between thermal behavior mechanism depending on characteristics of cooking equipment materials of portable gas ranges. It shows that slope of temperature change curve correlates with difference of heat capacity on thermal behavior characteristics experiment depending on materials of cooking equipment. In conclusion, temperature characteristics appear differently depending on variables such as materials of cooking equipment. Especially, it is necessary to restrict using cooking equipment made of stones, because it is very dangerous that temperature of can is rapidly increasing caused by high heat capacity of stone.