• Journal of Korean Society for Atmospheric Environment
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• v.32 no.6
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• pp.633-641
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• 2016

Two identical Particle Into Liquid Samplers-Total Organic Carbon (PILS-TOC) were operated to measure fine particle Water Soluble Organic Carbon (WSOC) for one week on Feb. in 2016. The dual instrument operations provided validated WSOC concentrations to have a continuous WSOC measurement during the sample analysis period. Both PILS-TOC instruments were operated downstream of an carbon denuder to remove positive adsorption artifacts associated with semi-volatile organic compounds. Comparison of WSOC showed good agreement each other. The linear regression had a coefficient of determination ($r^2$) of 0.92 and a regression slope of 1.01 for the first period. The lower collection efficiency due to lower steam temperature is discussed. In addition, the potential primary source related to WSOC based on the comparison of black carbon (BC) concentrations is explained. The results of good agreement between two PILS-TOC measurements can provide the validation of WSOC cooperations and knowledge regarding the origins of WSOC and their behaviors.

• Journal of the Korean earth science society
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• v.27 no.2
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• pp.177-187
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• 2006

Due to a lack of reproducibility and visibility of the conventional equipment for westerly wave simulation, it is difficult to have indoor experiments at high school that show the stream of Hadley cell. A modified improvement of the old one improves the problem. The side wall and bottom of the new equipment is made by copper and acrylic resin, respectively, in order to clarify the difference between the water temperature inside and outside of the water tank. The equipment also has a high quality digital record for generating exact analysis of the results. And we also carried out several experiments that relate theoretical and experimental aspection of westerly wave. Temperature Detected Sheet (TDS) in flow visualization unit provides not only visual information of liquid flow, but also clear understanding of the relation between upper and lower wind flow structure. And the liquid stream simulated in indoor experiment using proposed equipment is commensurate with westerly wave in real atmosphere. The efficiency of educational properties of the proposed equipment is verified indirectly by Likert Scales survey of high school teachers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.603-608
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• 2004

Traditional Jeju tofu with a hard texture was manufactured by traditional method with a compounded coagulant. The processing condition for industrial production was optimized by determining soaking of soybean, extraction and heat treatment of soymilk as well as concentration and composition of coagulant. Maximum yield of soymilk was obtained by grinding one part of soaked soybean with eight parts of water, and the soluble solid of soymilk was about 8$^{\circ}$Brix. The free thiol group in soymilk was maximally exposed by heating at 10$0^{\circ}C$ for 2 min. A vacuum cooker for heating soymilk was effective for the improvement of yield and texture properties of tofu. The hardness of traditional Jeju tofu was obtained by increasing pressing time and drying by a fan instead of soaking in cold water. Optimization of a traditional tofu production resulted in the increase of total yield and improvement of quality control. Texture of traditional Jeju tofu prepared in industrial production scale was analyzed by instrumental analysis and sensory evaluation. Traditional Jeju tofu showed higher score in the hardness, roasting taste and overall preference compared with a commercial tofu, showing significant difference in 5% significant level..

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.4
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• pp.456-464
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• 2010

RNA interference (RNAi) is an acknowledged useful and effective tool to study gene function in various cells. Here, we suppressed the Connexin 43 (Cx 43) gene expression during in vitro development of ovine pre-implantation embryos using the RNAi method. The 353 bp Cx 43 double-stranded RNA was microinjected into in vitro fertilized ovine zygotes, and the levels of target mRNA and protein were investigated. Control groups included uninjected zygotes or those injected with RNase-free water. The dsRNA injection resulted in the specific reduction of Cx 43 transcripts as analyzed by quantitative real-time RT-PCR and decreased protein levels as shown by Western blot analysis at the blastocyst stage. Microinjection of Cx 43 dsRNA led to 20.3%, 21.7% and 34.5% blastocyst rates and 19.2%, 37.5% and 41.3% hatched blastocyst rates in Cx 43 dsRNA-injected, water-injected and uninjected groups, respectively. Then the RNAi could not significantly affect cell number and cell death rates of blastocysts. Therefore, suppression of Cx 43 dsRNA and proteins did not apparently affect the development potential of ovine pre-implantation embryos but may play a role in embryo quality. RNAi technology is a promising approach to study gene function in early ovine embryogenesis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.2
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• pp.188-193
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• 2014

Seed viability testing provides valuable information for assessing seed lot germinability. However, most testing methods require destruction of seed prior to test. Because the dissected seeds for viability test cannot be used further evaluation, the nondestructively X-ray photography technique that can be applied for the evaluation of seed quality has been developed. In order to know the validity and accuracy of X-ray photography technique in seed evaluation test that conducted to remove the abnormal seed from a seed lot, we have compared the results from tetrazolium viability test, germination test and X-ray contrast method in cotton. Metallic salts treatment increased the efficiency of X-ray photographic method by enhancing the penetration of X-ray in abnormal or damaged seeds rather than normal seeds that have strong and well-organized tissues in seed. Cotton seeds presoaked for 16 hr in distilled water followed by soaking into metallic salt solution (5% NaI in water) for 60 min were easily classified seeds into dead seed and viable seed based on the radiography images obtained by X-ray radiation. We concluded that soft X-ray photography was reliable to find out the various defective characters due to heat and mechanical damage of seeds.

• Journal of Korean Elementary Science Education
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• v.36 no.1
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• pp.1-15
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• 2017

The purpose of this study is to analyze the problems of land and sea breeze model experiment that has presented in $5^{th}$ grade curriculum in chapter "Weather and our lives" and makes better model simulation so that learners can have better and more effective way to study it. To survey the opinions from dedicated teachers about land and sea breeze model experiment, we produced the survey through interview with science exclusive teacher from M elementary school. An elementary science education expert, 3 men of science EdD modified and complemented survey and started Delphi survey to 12 science teachers who have career teaching more than 3 years. The problems found in this survey were 'one heat bulb, short heating time, small temperature difference of water and sand, lack of class time, empty space between sand and water, back of transparent boxes, little amount of scent and the location of the it' etc. But the most of all, it is hard to see the successful result of the experiment. Based on these kinds of investigations, and lots of trial and error, redesigned the new model experiment that has the most similarity to the real one and high probability of success. According to this, it was able to see the smoke forms horizontal movement along the sand and the smoke goes in one circulation cycle. through this experiment, we made a conclusion that although those scientific experiments in textbook were developed through lots of considerations of expert, to consider the aspect of consumer, it needs to reach the educational agreement about simulation experiment so that It can lead to successful experiment and high quality education.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.8
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• pp.441-448
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• 2017

A method for measuring the concentration of surfactant in water was developed. In this technique, microbubbles were used as light scatterers. The polarization change of light scattered by microbubbles was analyzed by Mueller matrix analysis. $M_{11}$, one of the Mueller matrix elements, was found to be a key parameter inferring the surfactant concentration within the concentration range of 0 ppm to 60 ppm. The best results for this measurement were obtained when the scattering angle was $150^{\circ}$ and the extinction ratio was 56.2. This experimental result shows that the EPLS can be effectively used as a real time inspection method for water quality monitoring in lakes or rivers.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.6
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• pp.93-100
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• 2016

This study conducted a quantitative assessment on the environmental flows associated with climate change in the Gosam Reservoir, Korea. The application of RCP 8.5 climate change scenario has found that the peak value of High Flow Pulses has increased by 36.0 % on average compared to historical data (2001 ~ 2010), which is likely to cause disadvantage on flood control and management but the increase in peak value is expected to make a positive impact on resolving the issue of green algal blooms, promoting vegetation in surrounding areas and encouraging spawning and providing habitats for native species by releasing a larger amount of landslides as well as organic matters than the past. However, the decreasing pattern of the peak value of High Flow Pulses is quite apparent with the trend of delay on the occurrence time of peak value, necessitating a long-term impact analysis. The peak value of Large Floods shows a clear sign of decrease against climate change scenario, which is expected to lead to changes in fish species caused by degraded quality of water and decreasing habitats. A quicker occurrence of Small Floods is also expected to make an impact on the growth cycle of aquatic plants, and the reduction in occurrence frequency of Extreme Low Flows is to contribute to increasing the population of and raising the survival rate of native fish, greatly improving the aquatic ecosystem. The results of this study are expected to be useful to establish the water environment and ecological system in adapting or responding to climate change.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6877-6883
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• 2014

The continuous social development has led to increasing pollution in lakes. This study proposed the LVRI (Lake Vulnerability Resilience Indicator) based on the vulnerability assessment of climate change for an environmental risk assessment in lakes sufferign water pollution in an integrated aspect of the characteristics in lake watersheds. A total of 11 representative assessment factors were selected and constructed for 6 lake basins in the Geum River Watershed to calculate the exposure, sensitivity and adaptation indicators in a vulnerability assessment classification system. The weight coefficients for assessment factors of the LVRI were also calculated using the Entropy method. This study also compared the rank results of the lake environmental risk with/without the weight coefficients of assessment factors for the practical application of the proposed lake environmental risk assessment method. The lake environmental risk results estimated in this study can be used for long-term water quality analysis and management in lakes.

• Journal of the Korean Graphic Arts Communication Society
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• v.26 no.1
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• pp.29-38
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• 2008

Print-through is one of the most important attributes of print quality and has long been a subject to study. However, some aspects of print through are still in need to be enlighten. In this paper, different kinds of evaluating methods for print through are compared using densitometry, brightness, and image analysis. Printing conditions including ink feed, drying condition, and emulsification rate are systematically changed to effect print-through both on uncoated and coated commercial papers. Also several inks from different makers are introduced and compared in terms of print-through propensity. From the results, densitometry is not a good indicator for print through on the papers in this study. Ink feed has a strong effect on print through, especially for uncoated paper and should be considered in a point of optimum ink feed level in real world. Contribution of faster ink(oil) absorption seems to be more competitive than that of ink(oil) evaporation resulting in severer print-through for hot drying process. It is shown that ink-water emulsification rate increases print through at mild level but easy to decrease it with lower density due to the increase of water contents in emulsion. It is believed that the effect of absorption overwhelms that of density drop at mild emulsification level. This study does not include the effect of ink attributes in detail but shows that distinctive differences in print through may be resulted from various ink-makers and is finalized with some suggestions.