• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.2101-2106
• /
• 2011

It is reported that about more than 45% of damage shown in railroad rails include breakage of rail end which cross the center of Thermit welded zone. Thermite welding is always accompanied by numerous aluminum oxide and secondary inclusions, which may have a negative influence on the ductility and toughness of the weld metal. In this study the aluminum powder recycled by waste aluminum can was used for iron oxide generated after the process of welding rod and the remain aluminum was reduced by minimizing the quantity of aluminum. And complete dissolution was induced by using ferro Mn powder as the additive element. This study reviewed the applicability of heat treatment in the welded zone of rail using ceramic heating pad by carrying it out. This study could observe the improvement of the mechanical characteristics (UTS and elongation) and the changes of failure mechanism from brittleness to ductility. It could be found that improved strength and elongation result from pearilte fine structure.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2002.05a
• /
• pp.285-290
• /
• 2002

Screw in injection molding machine is affected by heat flux, pressure on inside barrel, geometry of screw including flight number, pitch and flight angle. Volumetric efficiency increases as the flight number increases, but it didn't show steady tendency according to helix angle of flight. Heat flux from heating pad and injection pressure play a very important role on the thermal behavior characteristics. The increased number of multi-flight is merits and demerits for a screw efficiency. So, we have to optimize flight number of the screw considering temperature, displacement, distortion and stress of the screw.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 1998.10a
• /
• pp.230-236
• /
• 1998

Thermal environment of greenhouse was investigated by thermo-tracer in this study. The Thermo-tracer is a high-sensitivity infrared thermometer of non-contact type. The infrared energy emitted from the measured object is converted into an electrical signal by the detector(HgCdTe) and display as a color or black & white thermal image by way of optical scanning, The experiment was conducted for Venlo-type greenhouse with pad & fan system. The temperature difference between measured by Thermo-trace and measured by HOBO sensor is maximum 0.8$^{\circ}C$. Thermo-trace is possible to use for the thermal environment analysis and diagnosis of a cooling and heating system of greenhouse.

• Tribology and Lubricants
• /
• v.16 no.2
• /
• pp.7-7
• /
• 2000

Using a coupled thermal-mechanical analysis, the dynamic distortion of the ventilated disk brakes has been presented for a high-speed train. The offset ratio between the maximum and minimum values of the thermal distortions has been analyzed as a function of a braking number. The computed FEM results show that the offset rations in radial direction are much greater than those of circumferentially distorted components. This means that the axial distortions in radial direction may dominantly produce thermally caused wears and cracks at the rubbing surfaces.

• Tribology and Lubricants
• /
• v.16 no.2
• /
• pp.99-105
• /
• 2000

Using a coupled thermal-mechanical analysis, the dynamic distortion of the ventilated disk brakes has been presented for a high-speed train. The offset ratio between the maximum and minimum values of the thermal distortions has been analyzed as a function of a braking number. The computed FEM results show that the offset ratios in radial direction are much greater than those of circumferentially distorted components. This means that the axial distortions in radial direction may dominantly produce thermally caused wears and cracks at the rubbing surfaces.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2001.04a
• /
• pp.28-33
• /
• 2001

Screw conveyors are used extensively in industrial for conveying and elevating materials. Despite their apparent simplicity, the mechanics of the conveying action is very complex. so many engineers depend on experiential data. Capacities of screw are pumping, steady flow of polymer melts, steady volumetric throughput etc. they are affected by geometry of screw, heat flux, pressure on inside barrel, rotating velocity, friction coefficient at screw surface etc. by computation volumetric efficiency increases as rotating velocity increases and decreases as friction coefficient increases. also it decreases with short pitch length. and double flight screw is more effective than single flight screw. The temperature of polymer melts by heating pad and injection pressure play a very important role in the injection molding machine. so in this paper we analyze thermal distortion and stress of screw includes pressure and temperature distributions by finite element analysis to understand what design factors influence on volumetric throughput efficiency of the screw and thermo-mechanical characteristics of screw.

• Tribology and Lubricants
• /
• v.15 no.2
• /
• pp.199-205
• /
• 1999

Using a coupled thermal-mechanical analysis, the thermal distortion of the ventilated disk brakes has been investigated based on the air cooling effects during 15 braking operations. The FEM results show that the bendings and distortions of the disk toward the left side are decreased, but the sinusoidal distortion of the disk rubbing surface along the arc length of the vent hole is highly increased by increasing the convective air cooling effects, which is heavily related to the squeal, wear and micro-thermal crackings at the rubbing surfaces due to uneven dissipation rates of friction heatings.

• Proceedings of the KIEE Conference
• /
• 2002.07d
• /
• pp.2710-2711
• /
• 2002

Conventional direct moxibustion remedy for cancer medical treatment has used a number of moxa lump for a surgical operation of patient However such a remedy has troubles in operating the moxibustion and causes the risk of burn. In order to get rid of the problems we have suggested the multiple heating pad with the Artemisia patch.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.11
• /
• pp.1692-1696
• /
• 2004

This paper presents the thermally induced hot spot characteristics of rubbing surface in the friction pad disk brake. During the braking period, the rubbing surface with irregular asperities that are strongly engaged in rough surface, wear, and deformed surface due to a friction heating may produce an irregular distorted geometry of the disk surface. The tribological interactions between the disk and the pads are unstable if the contact stress is severe, in which the irregularity develops the contact pressure distribution, leading eventually to localized contact, high temperature and formation of hot spots. The computed results of contact spots that are simulated using a coupled thermal-mechanical analysis present sinusoidal distortions and localized extrusions of the disk surface, which are strongly related to a hot spot in the practical disk brake.

• Journal of East-West Nursing Research
• /
• v.21 no.2
• /
• pp.133-139
• /
• 2015

Purpose: The purpose of this study was to identify the effects of thermotherapy on abdominal distension and pain during colonoscopy. Methods: This study used a nonequivalent control group and a non-synchronize design. Twenty-nine participants were assigned in an experimental group and 29 in the control group. For the experimental group, electronic heating pad was applied before test throughout the entire procedure. Results: Abdominal distension and total time required for colonoscopy significantly were lower in the experimental group than those in the control group. Conclusion: The results suggest that thermotherapy can be effective to improve abdominal distension and colonoscopy time in patients with colonoscopy. Therefore, thermotherapy can be recommended for those patients undergoing of colonoscopy.