• Journal of Conservation Science
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• v.26 no.3
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• pp.277-294
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• 2010

The Seosanmaaesamjonbulsang (National Treasure No. 84) consists of light gray and coarse to mediumgrained biotite granite with partly developed pegmatite and quartz vein. The host rock is divided into dozens of rock blocks with various shape along irregular discontinuity plane. The evaluation results of discontinuity systems reveal that the host rock were exposed to instable sloping environments. Results of deterioration diagnosis show that the degree of damage has been made worse by physical weathering and surface discoloration laying stress on part that vertical and horizontal joints are massed. Generally, deterioration rate of the triad Buddha surface cover with 42.7%, however, the rate of physical weathering and surface discoloration are subdivided to 9.6% and 33.1%, respectively. Ultrasonic measurements indicate that the triad Buddha was reached highly weathered grade in general. And the rock material was weaken to show low velocity zone of 1,000m/s along irregular joint systems. Indoor and outdoor mean relative humidity of the shelter was recorded more than 70% during every season, and high frequency appears in high relative humidity range over 95%. Such environments seem to have produced dew condensation on the rock surface with rainfall and supply water, promoted physical, chemical and biological weathering along crack and joint, resulting in high permeation of water and percentage of water content. Therefore, it is judged that for scientific conservation of the triad Buddha it needs environment control through persistent preservation environment monitoring including water problem.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.13-20
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• 2006

The changing patterns of water temperature and turbidity in streams entering Imha Reservoir were studied. The turbidity variation near the intake tower in Imha Reservoir was investigated in relation with the variation of water temperature and turbidity in streams. Water temperature was estimated using multi-regression method with air temperature and dew point as independent variables. Peak turbidity was also estimated using non-linear regression method with rainfall intensity as an independent variable. Although more independent variables representing watershed characteristics seem to be needed to increase estimation accuracies, the methodology used in this study can be applied to estimate water temperature and peak turbidity in other streams.

• Journal of Astronomy and Space Sciences
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• v.24 no.4
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• pp.339-348
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• 2007

KASINICS (Korea Astronomy and Space Science Institute Near Infrared Camera System) is equipped with a InSb array which can observe $1-5\;{\mu}m$ bands in near-infrared. The absorption and emission by telluric water vapor becomes serious in the bands longer than $3\;{\mu}m$. We measured PWV (precipitable Water Vapor) levels above Bohyusan Optical Astronomy Observatory and Sobaeksan Optical Astronomy Observatory from July 2006 to August 2007 using the GPS PWV measurement system of KASI. We found that monthly averaged PWVs are lower than the prediction using dew-point temperature and as low as above Kitt Peak from September to February.

• Journal of the Korean Society of Earth Science Education
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• v.11 no.1
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• pp.21-37
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• 2018

The purpose of the study is to visualize the concept of water circulation in elementary school students through science behavioral system. Elementary school students found it difficult to understand concepts related to the water cycle. Most of the elementary school children think it rains because the clouds are heavier. It is most difficult to explain invisible concepts to elementary school children. Also, experiments in current textbooks are likely to disrupt scientific concepts. Accordingly, conventional water cycle, dew, fog, and cloud experiments were integrated into one system. The researchers then developed a device that allowed students to see the water's circulation at a glance. It is intended to enable integrated thinking on evaporation, condensation and precipitation. In addition, a instruction program to guide students using the system has been developed to demonstrate its effectiveness. Employing a quasi-experimental design, the participants were measured on their concepts of evaporation, condensation, and water circulation before and after participation. The findings indicated that the experiment is more effective in changing the concepts of evaporation, condensation, and water circulation than in previous experiments. Also, the optimal conditions for making use of the device were found, and there were no various experimental parameters, such as condensation.

• Journal of the Korean earth science society
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• v.31 no.3
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• pp.288-299
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• 2010

Recently, scientific literacy means not only the acquisition of scientific knowledge but also the linguistic ability to participate in a scientific discourse community. Keeping this in mind, this study investigated middle school students' writings about phase transitions of water in air. Sixty seven students at 9th grade (age 15) students participated in this study and wrote two individual short texts. The result of text analysis can be summarized as follows: (1) students had problems with familiar scientific terms such as 'water vapor' and 'steam' as well as unfamiliar ones like 'dew point'. (2) Students described right semantic relations and at the same time wrong ones more in the idea formed from everyday experience than those from school instruction. (3) While students showed action and process centered writing in text about everyday phenomenon, they showed more preference for technical words and nouns in text about school science. This study suggest that students could develop linguistic ability of science from both spontaneous process based on experience and formal and theoretical learning; the former in forming various semantic relations, the latter in technical and abstract aspect of scientific writing.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.

• Journal of Conservation Science
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• v.33 no.4
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• pp.283-295
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• 2017

It is crucial to measure meteorological elements in relation to the biodeterioration of building cultural heritages. The Beopjusa and Seonamsa temples located respectively in Chungbuk and Jeonnam provinces, Korea, exhibit biological damage to the building cultural heritages and cause noticeable climatic differences. To compare biodeterioration environments of the abovementioned temples, 10 meteorological elements were observed, and particulate matter (TSP) was collected at each location. Furthermore, a correlation analysis was conducted between meteorological elements, and between meteorological elements and TSP. The local meteorology at Beopjusa temple characteristically showcased high total horizontal radiation, UV radiation, evaporation, wind speed, and TSP concentration, whereas, that at Seonamsa temple showcased high temperature, humidity, dew point temperature, air pressure, precipitation and number of days with precipitation. An elemental analysis of TSP revealed the presence of sae-salts at Seonamsa temple, and compared to that of Beopjusa temple, the monthly frequencies of biogenic aerosol and Fe-containing particles were higher. The correlation analysis showed that wind speed and humidity were major meteorological factors at Beopjusa and Seonamsa temples, respectively. Subsequently, the characteristics of the local meteorology at Seonamsa temple are expected to affect the biological damage of the building cultural heritages, which is favorable for the growth of various organisms.

• Corrosion Science and Technology
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• v.11 no.1
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• pp.1-8
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• 2012

The development of martensitic grades which can be processed in continuous galvanizing lines requires the reduction of the oxides formed on the steel during the hot dip process. This reduction mechanism was investigated in detail by means of High Resolution Transmission Electron Microscopy (HR-TEM) of cross-sectional samples. Annealing of a martensitic steel in a 10% $H_2+N_2$ atmosphere with the dew point of $-35^{\circ}C$ resulted in the formation of a thin $_{C-X}MnO.SiO_{2}$ (x>1) oxide film and amorphous $_{a-X}MnO.SiO_{2}$ oxide particles on the surface. During the hot dip galvanizing in Zn-0.13%Al, the thin $_{C-X}MnO.SiO_{2}$ (x>1) oxide film was reduced by the Al. The $_{a-X}MnO.SiO_{2}$ (x<0.9) and $a-SiO_{2}$ oxides however remained embedded in the Zn coating close to the steel/coating interface. No $Fe_{2}Al_{5-X}Zn_{X}$ inhibition layer formation was observed. During hot dip galvanizing in Zn-0.20%Al, the $_{C-X}MnO.SiO_{2}$ (x>1) oxide film was also reduced and the amorphous $_{a-X}MnO.SiO_{2}$ and $a-SiO_{2}$ particles were embedded in the $Fe_{2}Al_{5-X}Zn_{X}$ inhibition layer formed at the steel/coating interface during hot dipping. The results clearly show that Al in the liquid Zn bath can reduce the crystalline $_{C-X}MnO.SiO_{2}$ (x>1) oxides but not the amorphous $_{a-X}MnO.SiO_{2}$ (x<0.9) and $a-SiO_{2}$ oxides. These oxides remain embedded in the Zn layer or in the inhibition layer, making it possible to apply a Zn or Zn-alloy coating on martensitic steel by hot dipping. The hot dipping process was also found to deteriorate the mechanical properties, independently of the Zn bath composition.

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.153-163
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• 2010

This study was carried out to establish an improved bioassay system, whole-plant bioassay which is more effective in developing natural herbicides for foliar treatment such as herbicidal essential oils. Two bioassay systems using four weed species (Echinochloa crus-galli, Digitaria sanguinalis, Aeschynomene indica, and Abutilon theophrasti), spraying method and spotting method, were established. Spraying method is applicable if the amount of test compounds is enough, while spotting method is useful for the small amount of test compounds. The initial application rate was desirable at $2,500{\sim}5,000\;{\mu}g\;mL^{-1}$. Herbicidal activities were higher in the NOP treatment when compared to the Tween 20 treatment. To efficiently evaluate volatile compounds such as essential oils, if the compound-treated pots were incubated in dew chamber for about 10hrs, better results were obtained in the degree and stability of herbicidal responses. When the efficiency of bioassay systems established in this study was compared, the spraying method was minimized four times to the conventional method that has beed used for screening of synthetic compounds in KRICT. On the other hand, in the spotting method, screening for development of a natural herbicides was possible even in level of 1/100 test volume and 1/200 amounts of test compound compared to the spraying method.

• Korean Journal of Construction Engineering and Management
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• v.19 no.4
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• pp.34-42
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• 2018

Apartment is a typical type of housing preferred by the majority of people. However, and defect disputes occur because various defects such as cracks, subsidence, breakage, water leakage, dew condensation and dropout are confirmed with numerous structures and finishing materials. From this point of view, this paper analyzes defect frequency and costs of each warranty period by work types, and estimates defect risks by using defect dispute cases. It examined about 5,337 defect items for 32 apartment over ten years old. In this paper, there are 10 types of work types and the warranty liability period is divided into 6 categories. Based on these categories, defect frequency and costs are investigated, and finally defect risk of the warranty liability period by work types confirmed. As a result of this analysis, it was found that defect risk in RC and finishing work is very high. Especially the RC work revealed that there is a high risk of trying from the third year onwards and it was found that the defect risk up to the second year is high in the finishing work. Due to aging of RC structure, the defect risk gradually increases, and finishing work initially cause defect disputes because of the housing environment.