• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.6-7
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• 2018

In the previous study, durometer, namely rubber hardness tester Was used to confirm the possibility of using the setting time of concrete for determination. in this study, the possibility of using condensation time judgment condensation estimation system by comparing the measuring station setting estimation system Measuring needle of the proctor penetration resistance tester by newly making a measurement needle and refining the coagulation estimation system Want to make sure. As a result of this study, it was possible to use one condensation estimation system showing similar correlation between the two types of durometer showing high correlation with the penetration resistance value of proctor testers, It is considered to be fruitful to use the dew condensation estimation system for determining the setting time.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.4
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• pp.391-396
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• 2015

When the temperature of a flange in a refrigerator is reduced to the dew point, condensation is generated on the flange. Generally, hot lines, having a temperature of $35^{\circ}C$, are located near the flange to increase its surface temperature above the dew point. Hot lines are installed in close contact with the flange in order to increase the heat transfer from the hot lines to the flange surface. Through this work, the effects of the hot line shape and installation conditions, including a gap between the hot line and flange, and the function of a spacer in the inner case of the refrigerator were investigated. Additionally, an optimal shape of the inner case for easy assembling is proposed considering the contact between the hot line and flange.

• Journal of the Korean earth science society
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• v.41 no.6
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• pp.684-694
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• 2020

In this study, we developed a rubric for assessing middle school students' conceptual understanding about dew point. For this purpose, we analyzed 9th grade students' responses collected by using a multi-tiers constructed-response item of National Assessment of Educational Achievement (NAEA) and classified the types of the responses according to their characteristics. In addition, we analyzed the distribution of student response types according to mean achievement scores and developed an assessment rubric of conceptual understanding about dew point. The findings are as follows: First, the analysis of student responses to finding dew point in the saturation curve showed that many students had no or lack understanding of the scientific concept of dew point. Second, as a result of analyzing the student response to the water vapor condensation process at dew point, the proportion of scientific conception types was very low, while the proportion of misconception types was relatively high and the types varied as well. Third, a four- level assessment rubric was developed based on the analysis of the distribution of student response types according to the mean achievement scores. Based on the findings, we suggested the development and utilization of assessment rubric in the field of Earth science education.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.4
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• pp.429-434
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• 2011

Bulk cargo loaded into ship can be damaged by various kinds reasons. This paper aims to analyze about cargo damage of coil carrier ship due to condensation. Condensation is the formation of liquid drops of water from water vapor. Condensation consists of small drops of water which form when warm water vapour or steam touches a cold surface such as a window. In general, condensation have occurred by temperature difference at large building and ship's tank. It is phenomenon that can occur often to oceangoing vessel moving temperature difference places in similar time. This paper proposes a new method using dehumidification device and fan heater to prevent bulk cargo damage of coil carrier ship from condensation.

• Land and Housing Review
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• v.2 no.3
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• pp.269-276
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• 2011

Recently, the chance of dew condensation in apartment buildings is increasing because of several reasons. For example, ventilation rate has been decreased because of high-insulations and airtightness for saving energy. Besides, the humidity has been made by drying washes, cooking and bathing inside of apartment buildings. However, there is lack of resonable design criteria for preventing condensation in real life and real surroundings. Therefore, this study is aimed at making a resonable design criteria of preventing condensation by measuring the indoor temperature and humidity in real life. In addition to this, it is aimed at making a resonable outdoor condition and classifying regions by using weather data. The following are the results. The interior criterion for condensation was set up $25^{\circ}C$ and a relative humidity of 55%. The outdoor criterion for condensation was set up $20^{\circ}C$, $-15^{\circ}C$, and $10^{\circ}C$ respectively for the hard frost, middle, and southern areas.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.7
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• pp.607-616
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• 2002

This study has been conducted to evaluate the applicability of the control method in the dehumidification-integrated radiant floor cooling system in terms of stability of the room air temperature and the control variables through experiments. To do this, the relationship between the control variables in preventing floor surface condensation is first analyzed and the control method is predetermined through simulations. The results are as follows. First, it is necessary to determine the operation status of the dehumidification system according to the relationship between floor surface temperature and dew point temperature in the conditioned space. Second, outdoor reset with indoor temperature feedback control is better than on/off bang-bang control with respect to temperature stability in controlling the room air temperature and the possibility of energy savings. Finally, the humidity sensor can be located with the current thermostat in that there are small differences in absolute humidity in vertical distribution.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.533-542
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• 2019

As energy costs increase, more people has become interested on energy efficiency and savings in residential buildings. The two main subjects related to energy in residential buildings are insulation and condensation. There are two approaches to prevent condensation; increasing air tightness and maintaining the temperature inside of the wall structure over the dew point, which is in turn related to insulation. Even though the Korean government has highlighted the importance of energy efficiency for residential housings, and in spite of the customers' demands, the timber construction industry is still using conventional light-frame construction without even trying to improve energy efficiency. In this study, various types and combinations of wall structures were tested under cold outdoor and warm indoor temperatures to analyse the temperature gradients and to determine the possible sites of condensation in the wall structures. In addition to the experimental tests, three theoretical models were developed and their estimations of temperature change through the wall structure were compared with the actual measurements to evaluate accuracy of the models. The results of the three models agree relatively well with the experimental values, indicating that they can be used to estimate temperature changes in wall structures. The theoretical analysis of different insulation layers' combinations show that condensation may occur within the mid-layer in the conventional light-frame wall structures for any combination of inner-, mid-, and outer-layers of insulation. Therefore, it can be concluded that the addition of an inner and outer insulation layer or increasing the thickness of insulation may not be adequate to prevent condensation in the wall structure without preventing penetration of warm moist air into the wall structure.

• Journal of the Korean earth science society
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• v.40 no.6
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• pp.624-638
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• 2019

A questionnaire was administered, and all responses were analyzed to examine prospective teachers' conceptual understanding of the relationship between dew point temperature and absolute humidity in air parcels. The responses revealed that many prospective teachers have substantial misconceptions about the relationship. For example, some thought that the absolute humidity and the dew point temperature are proportional to each other, and that the dew point temperature is proportional to the water vapor mass in the parcel. The misconceptions seemingly stemmed from inadequate descriptions on the relationship in middle-school science textbooks of the 7th and 2007 revised curricula. The study notes that the first year students' textbook of the 2015 revised curriculum introduced the concepts of evaporation, condensation, and volume changes as a function of gaseous pressure and temperature, from a perspective of molecular motion. It is suggested that keeping this perspective in the middle school curriculum, while introducing water vapor pressure as the measure of water vapor amount and dew point temperature, should help prevent middle school teachers and students from having misconceptions. There should be a concerted effort to make the science curriculum more consistent and coherent across the grade levels.

• 보존과학연구
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• s.31
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• pp.103-120
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• 2010

Most of the important stone cultural heritage (National treasures and Treasures) in Korea are mainly located outdoor and considerably affected by the changes of the temperature, humidity and rainfalls. 541 of the stone cultural heritage are preserved as National treasure and Treasure. The pagodas occupy 187 remains and next 127 Buddha statues, 68 monuments, 60 stupas, and the others 74 stone cultural heritages. The shelter has been installed for one pagoda, 60 Buddha statues, 36 monuments and two stupas. The shelters are categorized in three shapes as traditional shape, modern shape, and others (tradition+modern). Approximately 100 of shelters that have constructed in traditional ways, and about nine of shelters have modern ways, and the only one has the combination shape of tradition and modern, which has been constructed since mid 1900s and repaired from the 1980s~2000s. Many researchers are studying for improvement of manners such as repairing, remodeling or removing of the shelter because problems have occured on shelters. Architectural form of traditional style of Korean timber building is respected, but it has problems on importing natural sunlight to the inside as well as ventilation and spacial problems. However, it needs to supplement policies to improve the positive roles of shelters such as prevention of artificial damage, blocking acid rain, and so on. For instance, the rock-carved Buddha Triad in Seosan, it had problems with viewing, contamination, and dew condensation on the surface. These problems decreased after dismantling the shelter, the space was made for improvement of viewing and dew condensation, and moisture problems were in better conditions. The velocity wind is an important factor in drying conditions on the surface of the rock, therefore the condition has improved after dismantling the shelter.

• Journal of Conservation Science
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• v.19
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• pp.85-98
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• 2006

Rock property of the Seosan Maaesamjonbulsang is composed of biotite granite with medium grained texture. The triad Buddha is highly deteriorated by the joint, fracture, break-out, exfoliation, dew condensation of the surface and discoloration of the secondary pollutant. Host rock of the triad Buddha is divided dozens of rock blocks with various shape, and developed irregular discontinuity planes. Besides, the host rock is promoted biological pollution due to the surrounding crowded vegetation and high humidity environment. As the results of structural stability, it is confirmed that developed discontinuity system in the host rock is exposed instability sloping environment. Therefore, the host rock and surroundings are required maintenance, and required preservation by continuance monitoring for understand behavior of discontinuity system.