• Journal of Hydrogen and New Energy
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• v.30 no.5
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• pp.455-464
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• 2019

Experiments were conducted to investigate the sensitivity of steel plate oxidation with temperature in a simulated furnace. Used steel plates were a general steel and a high tensile steel. Porous media burner (PM burner) used in model furnace was made for uniform temperature profile. The surrounding temperature was controlled by adjusting the flow rate of the mixture in the combustor. Oxide layer analysis was performed using SEM image analysis and EDS line scanning. Both steel sheets showed a tendency to increase the thickness of the steel sheet surface oxide layer as the temperature increases, and it was confirmed that the flaking phenomenon in surface oxidation layer appeared when the temperature was above a certain temperature.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2528-2533
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• 2007

Thermoforming is one of the most versatile and economical processes available for the manufacturing polymer products. The drawback of thermoforming is difficult to get uniform thickness of final products. For the distribution of thickness strongly depends on the temperature distribution of sheet, the adjustment of heater power is very important In this paper, an optimization study for getting uniform temperature distribution was carried out using dual optimization steps. At first, the steady state optimal distribution of heater power is searched by numerical optimization to get uniform temperature of sheet surface. In the second step, time-dependent optimal heater inputs have been found out to decrease the temperature difference through the direction of thickness using Rseponse Surface Method and D-optimal method. The optimization results show that the time-dependent optimal heater power distribution gives acceptable uniform sheet temperature in the field of forming temperature..

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1178-1183
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• 2004

Temperature distribution and heating characteristic of the panel heater for infrared heating have been investigated. The temperature variation with time is firstly measured with the thermocouple to figure out the response time of the heater to the power input. The heater reaches faster to the steady state in comparison to the ceramic heater. The infrared thermal imaging system is utilized to investigate the temperature distribution over the heater surface. The measured thermal images show that the thermal boundary layer induced by the free convection near the heater surface affects the temperature distribution on the surface. The images also show the fairly good uniformity of the temperature distribution in the core region of the surface.

• Transactions on Electrical and Electronic Materials
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• v.6 no.4
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• pp.164-168
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• 2005

Effects of high-temperature slurry were investigated on the chemical mechanical polishing (CMP) performance of tetra-ethyl ortho-silicate (TEOS) film with silica and ceria slurries by the surface analysis of X-ray photoelectron spectroscopy (XPS). The pH showed a slight tendency to decrease with increasing slurry temperature, which means that the hydroxyl $(OH^-)$ groups increased in slurry as the slurry temperature increased and then they diffused into the TEOS film. The surface of TEOS film became hydro-carbonated by the diffused hydroxyl groups. The hydro-carbonated surface of TEOS film could be removed more easily. Consequently, the removal rate of TEOS film improved dramatically with increasing slurry temperature.

• Journal of the Semiconductor & Display Technology
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• v.16 no.3
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• pp.116-120
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• 2017

Temperature uniformity of a wafer in a semiconductor process is a very important factor that determines the overall yield. Therefore, it is very important to confirm the temperature characteristics of the chuck surface on which the wafer is lifted. The temperature characteristics of the chuck depend on the external heat source, the shape of the cooling channel inside the chuck, the material on the chuck surface, and so on. In this study, CFD confirms the change of temperature characteristics according to the stacking order of ceramic materials on the chuck surface, and suggests the best lamination method.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.54-54
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• 2010

In this study, the correlation between temperature and the gel-content of the module were analyzed through experiments. Amorphous thin-film solar cell used in this experiment has a visible light transmission performance of 10%. In addition, ethylene vinyl acetate(EVA) film and the clear glass have been used for the modulation. The most important process is to laminate the module in the manufacturing process of BIPV(Building integrated photovoltaic) module. Setting parameters of laminator in the lamination process are temperature, pressure and time. Setting conditions significantly affect the durability, watertightness and airtightness of module. The most important factor in the setting parameters is temperature to satisfy the gel-contents. The bottom and top surface temperature of module are measured according to setting temperature of laminator. The results showed $145^{\circ}C$ of max temperature of the bottom surface and $128^{\circ}C$ of max temperature of top surface on the module at the temperature condition of $160^{\circ}C$. And at the another temperature condition of laminator with $150^{\circ}C$, the max temperature do bottom and top are $117^{\circ}C$ and $134^{\circ}C$ respectively. The temperature difference between bottom and top of the module occurred, that is because heat has been blocked by the clear glass and the bottom of the cells absorb the heat from the laminator. In this particular, the temperature difference between setting temperature of the laminator and the surface temperature of the module showed $15^{\circ}C$, because the heat of laminator plate is transferred to the surface of the module and heat is lost at this time. As a results, gel-content showed 94.8%, 88.7% and 81.7% respectively according to the setting temperature $155^{\circ}C$, $150^{\circ}C$ and $145^{\circ}C$ of the laminator. In conclusion, the surface temperature of module increases, the gel-contents is relatively increased. But if the laminator plate temperature is too high, the gel-content shows rather decline in performance. Furthermore, the temperature difference between setting temperature and the surface temperature of the module is affected by laminating machine itself and the temperature of module should be considered when setting the laminator.

• The Journal of Fisheries Business Administration
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• v.46 no.2
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• pp.31-41
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• 2015

This study aimed to analyze the relationship between sea surface temperature as a climatic element and catch amount of offshore and coastal fisheries in Korea using annual time series data from 1970 to 2013. It also tried to predict the future changes in catch amount of fisheries by climate change. Time series data on variables were estimated to be non-stationary from unit root tests, but one long-term equilibrium relation between variables was found from a cointegration test. The result of Granger causality test indicated that the sea surface temperature would cause directly changes in catch amount of offshore and coastal fisheries. The result of regression analysis on sea surface temperature and catch amount showed that the sea surface temperature would have negative impacts on the catch amount of offshore and coastal fisheries. Therefore, if the sea surface temperature would increase, all other things including the current level of fishing effort being equal, the catch amount of offshore and coastal fisheries was predicted to decrease.

• Journal of Environmental Impact Assessment
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• v.9 no.3
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• pp.177-183
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• 2000

The Landsat Thematic Mapper (TM) has suggested that spatial and spectral characteristics would be suited to evaluate water quality of lake. But, TM has not been commonly used for the analysis of in-land water quality, such as surface water temperature, chlorophyll-a, suspended sediments, and Secchi depth in domestic research. This paper summarizes the analysis of Landsat 5 - TM image collected on 22 Feb 1996 for evaluation of chlorophyll-a and surface temperature in the Lake Soyang. And, field measurements collected in the Lake Soyang were used to obtain water optical algorithms for calibration of satellite data. It is concluded that we can assess chlorophyll-a with remote sensing reflectance and surface temperature with thermal band in lake Soyang. However, surface temperature calculated with thermal band of Landsat TM are underestimated. Relationship between remote sensing reflectance and chlorophyll-a using the ratio of TM band 1 and band 3 is as follows; Y = 17.206 - 6.4711 * (Rrs(band1) / Rrs(band3)) $R^2$=0.8762 and, using the ratio of TM band 1 and band 2 as follows; Y = 57.77 - 35.771 * (Rrs(band1) / Rrs(band2)) $R^2$=0.8317.

• 한국전산유체공학회:학술대회논문집
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• 1996.05a
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• pp.40-45
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• 1996

This paper discribes the viscous interaction of Hypersonic Wedge Flows using Roe FDS and AUSM+. For this purpose we developed the frozen and the equilibrium code and numerically simulated the viscous interaction by changing the surface temperature and the mach number. We used curve fitting data in NASA Reference Publication 1181, 1260 to calculate equilibrium properties. We compare the equilibrium flow with the frozen flow. We conclude that the mach number and the surface temperature are significant parameters, as the surface temperature and the mach number increase the viscous interaction becomes stronger, and we must consider high-temperature effects in hypersonic flow

• Transactions of Materials Processing
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• v.15 no.8 s.89
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• pp.539-543
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• 2006

Experimental studies are carried out in order to investigate the effects of heat treatment on the surface machined by W-EDM. In this work, two ways of heat treatment after W-EDM are considered. As a comparison, the machined surface by a traditional method such as milling/grinding is also considered. Thereby, specimens are prepared by four different machining methods. Those are (1) milling and then grinding, (2) wire-cut electric discharge machining (W-EDM), and (3) low temperature heat treatment or (4) high temperature heat treatment after W-EDM. The resulting surface roughness are measured and the changes of surface microstructures are investigated using the scanning electron microscope (SEM) with energy dispersive X-ray spectrometer (EDS). In general, heat treatment after W-EDM result in smoother surface and better chemical composition at the machined surface. Especially, high temperature tempering could remove defects in the thermally affected zone, which cause an overall deterioration of the surface machined by W-EDM.