• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.2
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• pp.135-143
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• 2008

An emergy concept was used to evaluate the environment and economy of the estuarine areas of Yeongsan River, Seomjin River, and Han River in Korea. The emergy evaluations clearly showed ecological and socioeconomic characteristics of the estuarine areas that act as ecological and economic centers of surrounding areas. River, tide, and rain provided most of the renewable emergy inputs to the estuarine areas with their contribution to the total emergy input less than 8%. The estuarine areas mostly relied for their operation on the purchased emergy which accounted for $92{\sim}98%$ of the total emergy input to the systems. Emergy indices such as emergy use per unit area, population carrying capacity, environmental loading ratio, and emergy sustainability index revealed that the estuarine areas of Yeongsan River, Seomjin River, and Han River are not sustainable at the current level of economic activities in the areas. The ecological economic values of the environment of the areas were in the range of $7.29{\sim}22.06$ million Em\/ha/yr. They are more than twice that for the whole country, indicating the ecological and economic importance of the eatuarine areas. It is, therefore, urgent to establish and implement estuarine management policies to protect and restore the ecological and economic potentials of the estuarine areas of Yeongsan River, Seomjin River, and Han River. Management plans for the estuarine areas should include both demand-side measures such as reduction of population and economic concentration and consideration of ecological carrying capacity in planning stages for utilization and development of the areas, and supply-side ones such as restoration of degraded ecosystems and construction of new productive ecosystems.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.188-196
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• 2023

Wheat (Triticum aestivum L.) is an important crop in Korea, with a per capita consumption of 31.6 kg in 2019. In the southern region, wheat is grown after paddy rice, and it is harvested during the rainy season in mid-June. This timing, in combination with high humidity and untimely rainfall, activates the enzyme alpha-amylase, which breaks down starch in the wheat grains. As a result, sprouted grains have lower quality and value for flour. However, seeds that absorb water before sprouting are expected to maintain better quality. The aim of the study was to identify the critical period during wheat maturation when rainfall has the greatest impact on grain quality, to prevent price declines due to quality deterioration. Two wheat cultivars, Jokyoung and Hwanggeumal, were grown in a speed breeding room, and artificial rainfall was applied at different times after heading (30, 35, 40, 45, 50, and 55 days). The proportion of vitreous grains decreased from 40 to 55 days after heading (DAH). Both cultivars had chalky grain sections from 35 DAH, with Hwanggeumal having a higher proportion of vitreous grains. Starch degradation was observed using FE-SEM (Field Emission Scanning Electron Microscope) at 40 DAH for Jokyoung and 50 DAH for Hwanggeumal. Color measurements indicated increased L and E values from 40 DAH, with rain treatment at 55 DAH leading to a significant increase in L values for both cultivars. Ash content increased at 45 DAH, whereas SDSS decreased at 35 DAH. Overall, grain quality from 40 DAH until harvest was found to be affected to the greatest extent by direct exposure of the spikes to moisture. Red wheat showed better quality than white wheat. These findings have implications for the cultivation of high-quality wheat and can guide future research efforts in this area.

• Tuberculosis and Respiratory Diseases
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• v.57 no.5
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• pp.434-438
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• 2004

Background : An excessive endotracheal cuff pressure can cause tracheal injury, and insufficient cuff pressure may not generate an effective cuff seal. The peak inspiratory pressure influences the minimal occlusion pressure of the endotracheal tube cuff. However, the relationship between the minimal occlusion pressure and the tidal volume has not been investigated. This study was conducted to estimate the relationship between the tidal volume and the minimal occlusion pressure of the cuff. Methods : Ten mechanically ventilated patients were included. The minimal occlusion pressure of the cuff was measured using a pressure gauge. The basal tidal volume was increased and decreased as much as 10% whilst maintaining the same peak inspiratory pressure. The, minimal occlusion pressures were then measured in the high and low tidal volume state, respectively. Results : The peak inspiratory pressure was $32.6{\pm}4.72cmH_2O$ and the minimal occlusion pressure was $19.0{\pm}2.26$ mmHg in the basal ventilator setting. There was a significant relationship between the peak inspiratory pressure and the minimal occlusion pressure(r=0.77, p<0.01). The minimal occlusion pressure of the cuff was increased to $20.3{\pm}2.4$ mmHg in the high tidal volume state(p<0.05), and decreased to $16.8{\pm}3.01$ mmHg in the low tidal volume state (p<0.001). Conclusion : The minimal occlusion pressure of the cuff can be influenced by changes in the tidal volume as well as by the peak inspiratory pressure.

• Clinical and Experimental Pediatrics
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• v.46 no.11
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• pp.1061-1066
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• 2003

Purpose : The rising prevalence of childhood obesity may be due to an energy imbalance between food intake and energy expenditure. Recently, consumption of beverages in children has increased. The aim of this study is to provide useful information for the prevention and the control of childhood obesity by assessment of variable beverage consumption. Methods : Fight hundred seventy seven children(M : F=1 : 1.02, mean age; 9.7 years) from two primary schools in Seoul in May 2003 were enrolled. Body mass index(BMI) was calculated and the degree of obesity was classified into normal, overweight and obese groups by BMI percentile. Parental BMI, socio-economic factor, 3-day dietary intake, calory intake and beverage intake were examined by questionnaires. We researched beverages and classified them into six categories, milk, other milk products, soda, sports beverage, other beverage. Results : The prevalence of obesity was 7.2%. The parental BMI of the obese group were higher than those of the other groups. There was no significant difference in birth weight, or parents' intellectual and economic levels between the obese group and the other groups. There was no significant difference in daily total calory intake between the obese group and the other groups. The obese group of 7-9 year-old-males was higher than the other groups in sodas, and sports beverages intake. The obese group of 10-12 year-old-males was higher than the other groups in total beverage intake and other beverage intakes. The obese group of 10-12 year-old-females was higher than the other groups in other milk products. Conclusion : Excessive intake of beverages is associated with childhood obesity. Efforts to decrease intake of beverages may be important approaches to counter the rise in the prevalence of obesity.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.5
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• pp.1-12
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• 2014

Recently, the reenaction of place's memories that were considered sense of place based on its historical and structural characteristic were assumed important topics for recovering and making the park from industrial sites, such as factory, industrial complex, industrial city, labor residential development, landfill, etc., to the public all over the world. This research aimed to conduct some preliminary data for making the park's sense of place highly. So, after conducting the structural forms of sense of place for Seoul Forest and Seonyudo Park that were designed and built by considering its place memories actively, park planning and design implications that were considered its sense of place were suggested. The research results those were derived from the structural forms of sense of place for Seoul Forest and Seonyudo Park's are the following. First, the Structural Equation Modeling(SEM) on Seoul Forest and Seonyudo Park were determined that the natural-physical, artificial-physical, and experiential environmental factors' satisfaction of Seoul Forest and Seonyudo Park have an effect on forming the Sense of Place. In addition, the sense of place was affected by the willingness to visit. Second, according to its physical environment, the experiential factors, such as plays, exercises and etc., were more important relatively. Therefore, experiential factors should be considered significantly with physical factors to make the sense of place highly. Third, even the places were under similar category, the factors' and valuables' relative importance were changed. As the results of structural equation modeling said, specific valuables' related with each factors would be differentiated due to the places' characteristics. For example, the results were showed that natural-physical factor was more important than artificial-physical factor in Seoul Forest. On the other hand, artificial-physical factor was more important than the natural- physical factor. This research carries some significance for applying a quantitative research method(structural equation modeling) to various place to conduct the sense of place's structural model, for suggesting relative specific methods to make the sense of place, and for being a step forward to substance of sense of place. If further studies conduct focusing on various places to draw the forming models of sense of place that were based this research's analysis methods and results, those researches would contribute to make the urban place meaningful, characteristically and affectionately. Furthermore, those researches would contribute in making a humane and competitiveness city.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.400-407
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• 2011

To evaluate the aquatic ecological characteristics in Sinpyongcheon constructed wetlands for treating nonpoint source pollution, the removal rates of nutrients in water, the total amounts of T-N and T-P uptakes by water plants, and chemical characteristics of T-N and T-P in sediment were investigated. The concentrations of BOD, COD, SS, T-N and T-P in inflow were 0.07~1.47, 0.60~2.65, 0.50~4.60, 1.38~6.26 and $0.08{\sim}0.32mg\;L^{-1}$, respectively. The removal rates of BOD, COD, SS, T-N, and T-P were 14%, 6%, 18%, 24%, and 10%, respectively. The maximum amount of T-N uptake by water plants in August was $813mg\;plant^{-1}$ for Phragmites communis TRIV in $2^{nd}$ bed, $1,172mg\;plant^{-1}$ for Typha orientalis PRESL in $3^{rd}$ bed, respectively. The maximum amount of T-P uptake by water plants in August was $247mg\;plant^{-1}$ for Phragmites communis TRIV in $2^{nd}$ bed, $359mg\;plant^{-1}$ for Typha orientalis PRESL in $3^{rd}$ bed, respectively. Organic matter, T-N, and T-P contents in sediments were high in the order of $1^{st}$ bed > $2^{nd}$ bed > $3^{rd}$ bed. Microbial biomass C/N/P ratios in sediments in $1^{st}$, $2^{nd}$, and $3^{rd}$ were 78~110/3~6/1, 73~204/1~6/1, and 106~169/1~6/1, respectively.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.63-70
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• 2012

This study was conducted to investigated the distribution, ecological character and life cycle of Black Soldier Fly(BSF), Hermetia illucens, to determine effects of BSF on composing ability to the livestock feces. The distribution of BSF was defined in all parts of the country in Korea. Its main habitat was found to be areas near cattle sheds, feces sheds, living waste dump grounds, and food waste dump grounds. Excellent species of the bio-conversion using the livestock feces were selected out of two kinds of solider flies(Hermetia illucens and Ptecticus tenebrifer). And effects of BSF on composing ability to the livestock feces were pig feces 0.5 g, cattle feces 0.43 g and chicken feces 0.3 g per a larvae of BSF. In the examination of the ability of BSF to decompose food waste, volume of the livestock feces decreased by weight pig feces 77, cattle feces 83.62 and chicken feces 80%. Observed characteristics of BSF larvae and pupae stage were by developmental stage may be summarized as follows: size and length of larvae and pupae of BSF were higher than in pig feces and mixed sawdust treatments. In order to develop artificial indoor rearing techniques, The pupation and emergence rate were not visible the difference but important factor of the mating and egg-laying was a sun light. And it was visible the difference in mating ratio. Mating rate of H. illucens by seasonal change was the highest from May to July. Mating mostly occurred between 10 : 00 and 12 : 00 during which light intensity is high. As the egg-laying medium for artificial egg collection, calf feed and food waste were most effective. The ratio of egg-laying medium is waste food : sawdust(1 : 1) in volume. For egg-laying materials, flower foam and wood with holes were used; holes sized 3 ~ 5 mm in diameter, 7 ~ 10 mm in depth were most preferred for egg-laying.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.29-41
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• 2019

Terrestrial Gross Primary Production (GPP) is the largest global carbon flux, and forest ecosystems are important because of the ability to store much more significant amounts of carbon than other terrestrial ecosystems. There have been several attempts to estimate GPP using mechanism-based models. However, mechanism-based models including biological, chemical, and physical processes are limited due to a lack of flexibility in predicting non-stationary ecological processes, which are caused by a local and global change. Instead mechanism-free methods are strongly recommended to estimate nonlinear dynamics that occur in nature like GPP. Therefore, we used the mechanism-free machine learning techniques to estimate the daily GPP. In this study, support vector machine (SVM), random forest (RF) and artificial neural network (ANN) were used and compared with the traditional multiple linear regression model (LM). MODIS products and meteorological parameters from eddy covariance data were employed to train the machine learning and LM models from 2006 to 2013. GPP prediction models were compared with daily GPP from eddy covariance measurement in a deciduous forest in South Korea in 2014 and 2015. Statistical analysis including correlation coefficient (R), root mean square error (RMSE) and mean squared error (MSE) were used to evaluate the performance of models. In general, the models from machine-learning algorithms (R = 0.85 - 0.93, MSE = 1.00 - 2.05, p < 0.001) showed better performance than linear regression model (R = 0.82 - 0.92, MSE = 1.24 - 2.45, p < 0.001). These results provide insight into high predictability and the possibility of expansion through the use of the mechanism-free machine-learning models and remote sensing for predicting non-stationary ecological processes such as seasonal GPP.

• The Mathematical Education
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• v.62 no.3
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• pp.381-400
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• 2023

As the era of solving various and complex problems in the real world using artificial intelligence and big data appears, problem-solving competencies that can solve realistic problems through a mathematical approach are required. In fact, the 2015 revised mathematics curriculum and the 2022 revised mathematics curriculum emphasize mathematical modeling as an activity and competency to solve real-world problems. However, the real-world problems presented in domestic and international textbooks have a high proportion of artificial problems that rarely occur in real-world. Accordingly, domestic and international countries are paying attention to the reality of mathematical modeling tasks and suggesting the need for authentic tasks that reflect students' daily lives. However, not only did previous studies focus on theoretical proposals for reality, but studies analyzing teachers' perceptions of reality and their competency to reflect reality in the task are insufficient. Accordingly, this study aims to analyze in-service mathematics teachers' perception of reality among the characteristics of tasks for mathematical modeling and the in-service mathematics teachers' competency for designing the mathematical modeling tasks. First of all, five criteria for satisfying the reality were established by analyzing literatures. Afterward, teacher training was conducted under the theme of mathematical modeling. Pre- and post-surveys for 41 in-service mathematics teachers who participated in the teacher training was conducted to confirm changes in perception of reality. The pre- and post- surveys provided a task that did not reflect reality, and in-service mathematics teachers determined whether the task given in surveys reflected reality and selected one reason for the judgment among five criteria for reality. Afterwards, frequency analysis was conducted by coding the results of the survey answered by in-service mathematics teachers in the pre- and post- survey, and frequencies were compared to confirm in-service mathematics teachers' perception changes on reality. In addition, the mathematical modeling tasks designed by in-service teachers were evaluated with the criteria for reality to confirm the teachers' competency for designing mathematical modeling tasks reflecting the reality. As a result, it was shown that in-service mathematics teachers changed from insufficient perception that only considers fragmentary criterion for reality to perceptions that consider all the five criteria of reality. In particular, as a result of analyzing the basis for judgment among in-service mathematics teachers whose judgment on reality was reversed in the pre- and post-survey, changes in the perception of in-service mathematics teachers was confirmed, who did not consider certain criteria as a criterion for reality in the pre-survey, but considered them as a criterion for reality in the post-survey. In addition, as a result of evaluating the tasks designed by in-service mathematics teachers for mathematical modeling, in-service mathematics teachers showed the competency to reflect reality in their tasks. However, among the five criteria for reality, the criterion for "situations that can occur in students' daily lives," "need to solve the task," and "require conclusions in a real-world situation" were relatively less reflected. In addition, it was found that the proportion of teachers with low task development competencies was higher in the teacher group who could not make the right judgment than in the teacher group who could make the right judgment on the reality of the task. Based on the results of these studies, this study provides implications for teacher education to enable mathematics teachers to apply mathematical modeling lesson in their classes.

• Journal of Dairy Science and Biotechnology
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• v.33 no.2
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• pp.119-127
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• 2015

To date, detection of microbial populations in dairy products has been performed using culture media, which is a time-consuming and laborious method. The recently developed chromogenic media could be more rapid and specific than classical culture media. However, the newly developed molecular-based technology can detect microbial populations with greater rapidity and sensitivity than the classical method involving culture media and chromogenic media. This molecular-based technology could provide various options for monitoring the characterization of different states of bacteria and cells. Thus, it could help upgrade the processing system of the dairy industry so as to maintain the safety and quality of dairy foods. Among the various newly developed molecular-based technologies, flow cytometry can potentially be used for monitoring microbiological populations in the dairy industry if official international standards are available for this purpose. When omics technology would have biomarker identification, it could be regarded as the rapid and sensitive analytical methods. Methods based on PCR, which has become a basic technique in microbiological research, can be developed and validated as alternative methods for quantification of dairy microorganisms. This review discusses methods for monitoring microbiological populations in dairy foods and the limitations of these studies, as well as the need for further research on such methods in the dairy industry.