• Corrosion Science and Technology
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• v.9 no.6
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• pp.247-253
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• 2010

The characteristics of selective oxidation prior to hot-dip galvanizing with the annealing atmosphere dew point and chemical composition in dual-phase steels and their effect on the inhibition layer formation relevant to coating adhesion have been studied using a combination of electron microscopic and surface analytical techniques. The annealed and also galvanized samples of 3 kinds of Si/Mn ratios with varied amounts of Si addition were prepared by galvanizing simulator. The dew point was controlled at soaking temperature $800^{\circ}C$ in 15%$H_2$ -85%$N_2$ atmosphere. It was shown that good adhesion factors were mainly uniformity of oxide particle distribution of low number density and low Si/Mn ratio prior to hot-dip galvanizing. Their effect was the greatly reduced coating bare spots and the formation of uniform inhibition layer leading to good adhesion of Zn overlay. The mechanism of good adhesion is suggested by two processes: the formation of inhibition layer on the oxide free surface uncovered with no $SiO_2$-containing particles in particular, and the inhibition layer bridging of oxide particles. The growth of inhibition layer was enhanced markedly by the delayed reaction of Fe and Al with the increase of Si/Mn ratio.

• The Journal of the Korea Contents Association
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• v.11 no.11
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• pp.42-48
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• 2011

This paper presents a bridge road surface frost prediction and monitoring system. The node sensing hardware comprises microprocessor, temperature sensors, humidity sensors and Zigbee wireless communication. A software interface is implemented the control center to monitor and acquire the temperature and humidity data of bridge road surface. A bridge road surface frost occurs when the bridge deck temperature drops below the dew point and the freezing point. Measurement data was used for prediction of road surface frost occurrences. The actual alert is performed at least 30 minutes in advance the road surface frost. The road surface frost occurrences data are sent to nearby drivers for traffic accidents prevention purposes.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.5
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• pp.1083-1089
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• 2014

The aims of this study are to find out the possibility of the charcoal as a desiccant. The only humidity control under high temperature and high humidity environment can be provided to the thermal comfort at indoor environment. Functionality of charcoal is known to be deodorization, antiseptic effect, filtering effect and humidity control. But research related to humidity control in the country not yet. Thus, the dehumidification capacity of the charcoal experimental results to see the results were as follows : 1) Entering the experimental humidification is 148.02 g/h, 161.05 g/h and 243.2 g/h when air velocity was changed 1.5 m/s, 1.7 m/s and 2.0 m/s. 2) When the basis weight of the charcoal 2.0 m/s air velocity to obtain the largest number of adsorption capacity. 3) Dru bulb temperature and dew point temperature ware measured at front and rear of the charcoal. Absolute humidity is calculated from the measured Dry bulb temperature and dew point temperature. The quantity of dehumidification is calculated from absolute humidity is the largest 129.6 g/h at the air velocity 2.0 m/s.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.55-61
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• 2012

Road signs are important facilities in terms of providing information to driver, they are helpful for driver's judgment as deliver it's own information. However if there is occurrence dew on the road sign because of the change of temperature and humidity, it can be cause of accidents. Therefore it is necessary to develop anti-dew or dew resistance technology. In this research the anti-dew technologies such as insulation road sign and anti-dew film were compared with normal road sign, and the effectiveness analysis was conducted for each alternatives. The quantity of dew on the road sign was check using ANOVA and Tukey HSD and the relation between the retro-reflectivity and quantity of dew on the sign was check using Pearson correlation coefficient. As a result, the sample of anti-dew film attached road sign showed lesser quantity of dew compared with normal road sign. After 90 seconds, the difference of dew quantity for anti-dew film and insulation road sign showed statistically significant result. The relation of between quantity of dew and retro-reflectivity was inverse correlation. As a result, when analyzed the quantity of dew and retro-reflectivity a point of view anti-dew effectiveness, the anti-dew film and insulation road sign showed meaningful result.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.6-9
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• 2008

The efficiency and life time of the proton exchange membrane (PEM) fuel cell system is critically changed with its humidity which should be maintained properly during dynamic operation. Membrane humidifier is required to regulate proper humidity level for the design point of the PEMFC system. In this study, we presented the performance of the cylindrical membrane humidifier which is operated as water-to-gas. Dry air pressure, liquid water flow temperature, and air flow rate were chosen as the operating parameters. Humidity level is expressed with dew point.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.285-290
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• 2009

The main thrust of this paper is to investigate acceptable supply air conditions of a dedicated outdoor air system (DOAS) for highrise apartment buildings. As for a typical $132-m^2$ apartment unit, it was assumed that centralized DOAS-Ceiling Radiant Cooling Panel was installed. Transient behavior and control characteristics of each system were modeled numerically using a commercial equation solver program. The optimized dew point temperature of the DOAS was discussed on the basis of the ASHRAE standard 62.1-2007 and the current Korean ventilation standard for apartments. It was found that the optimized dew point temperature of the DOAS supply air accommodating total latent load of a space is $11-12^{\circ}C$ and the appropriate supply air temperature of the DOAS is $11-12^{\circ}C$ in cooling period and neutral temperature of $18-20^{\circ}C$ in intermediate period.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.916-919
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• 2003

In this paper, we deal with a development of measurement system to apply the leakage rates test of primary containment in nuclear power plant. The measurement test about leakage rates in primary containment is one sort of test to prove safety of nuclear power plant. The parameters which are measured to calculate leakage rates are drybulb temperature, dew point temperature(or relative humidity), absolute pressure and flow. Overall, the measurement system consists of sensor module for data acquisition of the parameters, transfer module for wireless data communication and control module to control system and to calculate leakage rates. Because existing measurement systems are difficult to set in field, we pursued convenience of use, we applied wireless data communication and individual form module using battery. We also changed for the better in confidence. Recently, we are developing a drybulb temperature and a dew point temperature sensor module. We describe about function of developed measurement system, its standard and an plan for verification of measurement system.

• Applied Microscopy
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• v.43 no.1
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• pp.40-45
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• 2013

Phase transformation by the Mn-deprivation was observed in the high-Mn twinning-induced plasticity-aided steel. Mn-depletion was induced by the formation of Mn-O oxide during the dew-point control process at temperature above $-20^{\circ}C$, which changed austenitic parent phase to multi-grained ferrite. Mixture of Al-O, Al-Mn-Si-O oxides were observed at the grain boundaries of transformed ferrite.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.3 s.22
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• pp.111-115
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• 2005

The compact storage of ammunitions in magazine causes serious dew problem on the surface of the shell. Lots of previous studies try to solve this problem by increasing the temperature of air in military magazine. They tried to reduce relative humidity by increasing the temperature of air, but all of them failed. One of the major reasons of these failures is analysed based on the point of view of physics.

• Progress in Superconductivity and Cryogenics
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• v.12 no.1
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• pp.66-70
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• 2010

The operational temperature range of thermosiphon is generally limited from the critical point to the triple point of the working fluid to maintain two-phase state. Thermosiphon with mixed working fluid has a potential to widen the operational temperature range. In this study, the physical behavior of mixed working fluid during the transient operation of thermosiphon was analyzed with temperature-mole fraction diagram. The condenser and the evaporator temperature variations were explained by the dew line and the bubble line of the mixture. It is encouraging that the thermosiphon operation commences early with larger fraction of high boiling point component, but the temperature gap between the condenser and the evaporator due to the separation of two components has a negative effect on the officient cool down process.