• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.183-186
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• 2007

The injection molding process has high accuracy and good reproducibility that are essential for mass production at low cost. Conventional molding processes typically use the water-based mold heating and air cooling methods. However, in the nano injection molding processes, this semi-active mold temperature control results in the several defects such as air-flow mark, non-fill, sticking and tearing, etc. Therefore, in order to control temperature of the molds actively and improve the quality of the molded products, the novel nano injection molding system, which uses active heating and cooling method, has been introduced. By using the Peltier devices, the temperature of locally adiabatic molds can be controlled dramatically and the quality of the molded patterns can be improved.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.647-653
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• 2000

In this research the heat regenerative technology was employed to eliminate frosting on evaporator coil and improve COP of the heat pump system. This heat regenerative device(HRD) has very simple structure consisting a geared motor and a porous fiber belt passing through alternatively between cold and warm air duct. The laboratory test showed that the heat pump system with HRD yielded an impressive COP higher than 3.5 at the outside air temperature of $-7^{circ}C$ in heating mode.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1623-1628
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• 2008

A temperature gradient focusing (TGF) via Joule heating phenomenon was numerically studied. The governing transport equations are implemented into a quasi-1D numerical model to predict the resulting temperature, velocity, and concentration profiles along a microchannel of varying width under an applied electric field. The model is used to analyze the effects of varying certain geometrical parameters of a microchannel on the focusing performance of the device. We show the effects of varying width of the microchannel having a fixed length, and propose the optimal geometry of the device. This method can be easily implemented into lab-on-a-chip (LOC) applications where focusing is required based on its simple design.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.12
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• pp.1017-1021
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• 2015

Induction heating has been applied to the preheating process in various industrial fields. It has been used as a simple device structure, limiting the heating zone through controlled variables, and free-welding positions. It would be helpful to weld thick plates with arc welding such as GMAW. The induction heating process is well suited to this process. In this study, in order to find suitable induction heating parameters, a simulation was conducted with multi physics S/W. Three kinds of material were heated by induction coils designed specially for thick plate. Consequently, steel and nimonic alloy were the most efficient materials for preheating by induction. It can be concluded that the induction heating process is a good method for preheating the thick plate.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.33 no.12
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• pp.99-106
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• 2017

Recently, the condensation and mold problems of apartment buildings has been growing due to high insulation and high air-tightness performance for energy saving. Most of all, occupants in residential buildings has suffered from property damages due to the condensation and mold of built-in furniture. Condensation at built-in furniture were generally found in winter at the of furniture's back panels, adjacent surfaces of wall, floor and ceiling. The aim of paper is to analyze the characteristics of adjacent area around built-in furniture's condensation problem and the thermal environment around the built-in furniture in winter through the field measurements at apartment buildings. In this research, the thermal conditions and surface temperature around the built-in furniture were measured during winter season. In this research, we analyzed thermal conditions for built-in furniture which were applied and not applied auxiliary heating device. In results, it is important to consider increasing surface temperature for using heater and decreasing absolute humidity due to the occupants' behavior around built-in furniture for preventing condensation.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.1
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• pp.39-43
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• 2002

In present much CMOS devices used in VLSI circuit and Logic circuit. With increasing a number of device in VLSI, the confidence becomes more serious. This paper describe the mechanism of breakdown on CMOS, especially n-MOS, based on Hydro Dynamic model with device self-heating. Additionally, illustrate the CMOS latch-up characteristics on simplified device structure on this paper.

• ETRI Journal
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• v.26 no.6
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• pp.575-582
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• 2004

Fully-depleted silicon-on-insulator (FD-SOI) devices with a 15 nm SOI layer thickness and 60 nm gate lengths for analog applications have been investigated. The Si selective epitaxial growth (SEG) process was well optimized. Both the single- raised (SR) and double-raised (DR) source/drain (S/D) processes have been studied to reduce parasitic series resistance and improve device performance. For the DR S/D process, the saturation currents of both NMOS and PMOS are improved by 8 and 18%, respectively, compared with the SR S/D process. The self-heating effect is evaluated for both body contact and body floating SOI devices. The body contact transistor shows a reduced self-heating ratio, compared with the body floating transistor. The static noise margin of an SOI device with a $1.1\;{\mu}m^2$ 6T-SRAM cell is 190 mV, and the ring oscillator speed is improved by 25 % compared with bulk devices. The DR S/D process shows a higher open loop voltage gain than the SR S/D process. A 15 nm ultra-thin body (UTB) SOI device with a DR S/D process shows the same level of noise characteristics at both the body contact and body floating transistors. Also, we observed that noise characteristics of a 15 nm UTB SOI device are comparable to those of bulk Si devices.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.852-857
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• 2014

This study was carried out to develop a simple, convenient, and reproducible testing device to determine wettability and dispersibility of dairy powders. The testing device consists of a sieve ($150{\mu}m$) attached to a sample chamber, sensors mounted on a supporting body and a main control unit containing a display panel. The sensors detect the difference in electrical resistance between air and water. A timer is automatically triggered by the sensor when the bottom of sample-loaded chamber contacts water in the petri dish. Wettability and dispersibility of commercial skim milk powders (SMPs) produced at different heating strengths (low-, medium-, and high-heat SMP) are compared using the new testing device. Wettability of the SMPs were correlated with particle size and are found to increase in the order of medium-, low-, and high-heat SMP regardless of the amount of sample tested. Dispersibility of SMPs showed the same trend and high heat-SMP which has the smallest particle size resulted in the lowest dispersibility. Unlike existing methods, the new testing device can determine both wettability and dispersibility of powders and successfully detected differences among the samples.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.946-951
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• 2009

The research aims to study a new, optimum and renewable energy application method that can cover the minimum energy and operation costs within a range of school budgets. By deriving the optimum application method, it is expected to maximize the cooling/heating and water heating energy saving efficiencies for educational facilities. Therefore, this research carried out a study on the new/renewable energy utilization technique diffusion expansion method and the optimum method. As a result, the first optimum plan was introduced with the multi-type geothermal heat pump 174kW + solar heat collector $94\;m^2$ + highly efficient electronic cooling/heating device (EHP) 249.4kW. On the other hand, the second optimum plan was induced as the multi-type geothermal heat pump 255.2kW + highly efficient electronic cooling/heating device (EHP) 168.2kW.

• Applied Microscopy
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• v.45 no.2
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• pp.95-100
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• 2015

The in-situ heating transmission electron microscopy experiment allows us to observe the time- and temperature-dependent dynamic processes in nanoscale materials by examining the same specimen. The temperature, which is a major experimental parameter, must be measured accurately during in-situ heating experiments. Therefore, calibrating the thermocouple readout of the heating holder prior to the experiment is essential. The calibration can be performed using reference materials whose phase-transformation (melting, oxidation, reduction, etc.) temperatures are well-established. In this study, the calibration experiment was performed with four reference materials, i.e., pure Sn, Al-95 wt%Zn eutectic alloy, NiO/carbon nanotube composite, and pure Al, and the calibration curve and formula were obtained. The thermocouple readout of the holder used in this study provided a reliable temperature value with a relative error of <4%.