• Journal of Climate Change Research
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• v.2 no.4
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• pp.297-307
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• 2011

This study investigates relation of food safety incidents with climate. Therefore food safety incidents and climate data during 1999 to 2009 have been analyzed. In situ observations of monthly mean temperature, maximum temperature, minimum temperature, precipitation, and relative humidity in 60 observation stations of Korean Meteorological Administration (KMA) have been used in this study. Food safety incidents data have been constructed by searching media reports following Park's method (2009) during the same period. According to the Park's method, 729 events were collected. To analyze its relations, food safety incidents data have been classified into chemical, biological, and physical hazards. Pearson product-moment correlation coefficients have been applied to analyze the relations. The correlation of food safety incidents has negative one with precipitation (-0.48), and positive one with minimum temperature(0.45). Precipitation has been correlated with biological and physical hazards more than chemical hazard. Temperatures (mean temperature, maximum temperature, and minimum temperature) have been correlated closely with chemical hazard than others. Food safety incidents data has been interblended with human behavior factor through decision-making processes in food manufacturing, processing, and consumption phases of "farm-totable" food processing. Act in the preventing damage will be obvious if the hazard were apparent. Therefore abnormal condition could be more dangerous than that of apparent extreme events because apparent events or extreme events become one of alarm over hazards. Therefore, human behavior should be considered as one of the important factors for analysis of food safety incidents. The result of this study can be used as a better case study for food safety researches related to climate change.

• Journal of Climate Change Research
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• v.4 no.4
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• pp.397-407
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• 2013

Seasons in Korea have very distinguishable features. Due to continental high pressure, spring in Korea is dry and has low precipitation. Due to climate change derived from the increase of greenhouse gases, climate variability had increased and it became harder to predict. This caused the spring drought harsher than usual. Since 1990s, numbers of chronic drought from winter to spring increased in southern regions of Korea. Such drought in the spring damages the growth and development of the crops sown in the spring and decreases its quantity. For stable agricultural production in the future, it is necessary to assess vulnerability of the relationship between spring drought and agricultural production as well as to establish appropriate measures accordingly. This research used CCGIS program to perform vulnerability assessment on spring drought based on climate change scenario SRES A1B, A1FI, A1T, A2, B1, B2 and RCP 8.5 in 232 regions in Korea. As a result, Every scenario showed that vulnerability of spring drought decreased from 2000s to 2050s. Ratio of decrease was 37% under SRES scenario but, 3% under RCP 8.5 scenario. Also, for 2050 prediction, every scenario predicted the highest vulnerability in Chungcheongnam-do. However, RCP-8.5 predicted higher vulnerability in Gyeonggi-do than SRES scenario. The reason for overall decrease in vulnerability of agriculture for future spring drought is because the increase of precipitation was predicted. The assessment of vulnerability by different regions showed that choosing suitable scenario is very important factor.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.415-423
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• 2018

Rice panicle architecture is an important factor affecting yield potential. Korean rice cultivars have a narrow genetic background for panicle architecture. To enhance the yield potential of Korean rice cultivars, we developed and characterized rice lines with new panicle architecture. Rice with improved panicle architecture has clustered spikelets and dense panicles (CD type). CD rice was derived from a cross between "Binhae Col.#1" carrying dense panicles, and "ARC10319" that has the clustered spikelets gene (Cl). CD rice lines had short and semi-erect panicles with two to five high density spikelets clustered at the tips of primary and secondary rachis branches. CD rice lines had dramatically increased numbers of spikelets; almost twice as many as those of Korean rice cultivars. The increase in spikelet number was mainly caused by the increased spikelets and branches on secondary rachises compared to those on primary rachises. The increase in spikelet number was expected to enhance the yield of CD rice by expanding sink capacity. However, the yield of selected lines; CD9, CD27, CD34, and CD39, did not reach the level of the Korean high-yielding cultivars "Boramchan" and "Hanareum2," due to the reduction in panicle number and grain weight, and poor ripening. Although no substantial yield increase was observed in CD rice, the panicle architecture of CD rice, clustered spikelets, and dense panicles could be new genetic resources as breeding material for diversifying panicle architecture and enhancing yield potential.

• Journal of Wetlands Research
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• v.20 no.4
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• pp.424-431
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• 2018

Stormwater runoff containing considerable amounts of pollutants such as particulates, organics, nutrients, and heavy metals contaminate natural bodies of water. At present, best management practices (BMP) intended to reduce the volume and treat pollutants from stormwater runoff were devised to serve as cost-effective measures of stormwater management. However, improper design and lack of proper maintenance can lead to degradation of the facility, making it unable to perform its intended function. This study evaluated an infiltration trench (IT) that went through a series of maintenance operations. 41 monitored rainfall events from 2009 to 2016 were used to evaluate the pollutant removal capabilities of the IT. Assessment of the water quality and hydrological data revealed that the inflow volume was the most relative factor affecting the unit pollutant loads (UPL) entering the facility. Seasonal variations also affected the pollutant removal capabilities of the IT. During the summer season, the increased rainfall depths and runoff volumes diminished the pollutant removal efficiency (RE) of the facility due to increased volumes that washed off larger pollutant loads and caused the IT to overflow. Moreover, the system also exhibited reduced pollutant RE for the winter season due to frozen media layers and chemical-related mechanisms impacted by the low winter temperature. Maintenance operations also posed considerable effects of the performance of the IT. During the first two years of operation, the IT exhibited a decrease in pollutant RE due to aging and lack of proper maintenance. However, some events also showed reduced pollutant RE succeeding the maintenance as a result of disturbed sediments that were not removed from the geotextile. Ultimately, the presented effects of maintenance operations in relation to the pollutant RE of the system may lead to the optimization of maintenance schedules and procedures for BMP of same structure.

• Journal of The Korean Association For Science Education
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• v.39 no.3
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• pp.363-377
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• 2019

This study reveals the aspects of subjectivity in the test results in a science-specific aspect when assessing science-related affective characteristic through self-report items. The science-specific response was defined as the response that appear due to student's recognition of nature or characteristics of science when his or her concepts or perceptions about science were attempted to measure. We have searched for cases where science-specific responses especially interfere with the measurement objective or accurate self-reports. The results of the error due to the science-specific factors were derived from the quantitative data of 649 students in the 1st and 2nd grade of high school and the qualitative data of 44 students interviewed. The perspective of science and the characteristics of science that students internalize from everyday life and science learning experiences interact with the items that form the test tool. As a result, it was found that there were obstacles to accurate self-report in three aspects: characteristics of science, personal science experience, and science in tool. In terms of the characteristic of science in relation to the essential aspect of science, students respond to items regardless of the measuring constructs, because of their views and perceived characteristics of science based on subjective recognition. The personal science experience factor representing the learner side consists of student's science motivation, interaction with science experience, and perception of science and life. Finally, from the instrumental point of view, science in tool leads to terminological confusion due to the uncertainty of science concepts and results in a distance from accurate self-report eventually. Implications from the results of the study are as follows: review of inclusion of science-specific factors, precaution to clarify the concept of measurement, check of science specificity factors at the development stage, and efforts to cross the boundaries between everyday science and school science.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.4
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• pp.457-467
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• 2019

To investigate the long-term variation characteristics of nutrients in the east coast of Korea, water temperature, salinity, dissolved oxygen, and nutrients were measured at three stations of Sokcho, Jukbyeon and Gampo coasts for five years from 2013 to 2017. For five years, the water temperature of the East Sea coast was in the range of $1.2{\sim}28.8^{\circ}C$, the salinity was in the range of 30.63~34.79 and the dissolved oxygen (DO) was in the range of 3.53~7.64 mL/L. Distribution and variation of the water environment factors in the study area were determined by the vertical stratification of water column and distribution of water temperature. The high DO concentration in Sokcho coast From 2015 to August 2016 is presumed to be the result of the southward inflow of North Korean Cold Water (NKCW). Concentrations of dissolved inorganic nitrogen (DIN, $NH_4-N+NO_2-N+NO_3-N$) ranged $0.11{\sim}24.19{\mu}M$, phosphate concentration ranged $0.01{\sim}1.75{\mu}M$, and silicate ranged $0.17{\sim}32.80{\mu}M$. The N:P ratio was in the range of 0.7~54.3 (mean 15.2) and the N:P slope was in the range of 11.67~13.75. The N:P ratios in this study were lower than the Redfield ratio (16), indicating that nitrate did act as a limiting factor in phytoplankton growth. The correlation ($R^2$) of total N:P ratio was as high as 0.95, indicating that the effect of the surrounding land or non-point sources was not significant. In conclusion, the spatial and temporal variation of nutrients in the east coast of Korea was determined by the vertical mixing of water mass with thermocline and mainly affected by physical factors such as influx of external water masses and coastal upwelling, and the influences from inflows from the land were minimal.

• Korean Journal of Heritage: History & Science
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• v.45 no.3
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• pp.114-159
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• 2012

The Northern Song Dynasty Period (北宋時代) was a drastic transitional era in all aspect of Chinese society including the politico-economic system, ideology and cultural trait. These changes that began in the late Tang (唐) Dynasty Period accomplished in the Northern Song Dynasty. In this phase, the fundamental change influenced in all institutional area; and among them, the capital city planning and its associating building technology to pile stone walls shows one of the significant change of those time. Based on the geographical factor, confluences of many rivers, the Kaifeing (開封) area where the BianLieng palace had developed as a political and economical centre since the Tang Dynasty when the Grand Canal was constructed. According to archaeological researches, the central city structure of Dongjing Walled Town was begun to plan in the late Tang Dynasty and formed in Five Dynasties. The fundamental functional change of city completed in the Midnorthern Song Dynasty. In spite of the relatively late beginning of archaeological investigations to Kaifeng Walled Town and Dongjing Walled Town due to unfavourable natural environment, excavations inaugurated since 1981 have achieved the significant investigations including the actual measurement and excavation to the outer wall, the preliminary excavation to the inner city area, the investigation and excavation to the royal palace of Song and the survey to the royal palace of King Zho in the Ming (明) Dynasty. These surveys have provide important data to reconstruct the 변량 palace, and elucidate the characteristics of city plan in the Dongjing Walled Town and the institutional change of capital city plan of the Northern Song Dynasty. The basic layout of Dongjing Walled Town reflect the realisation of ideality of the late Chinese medieval capital city structure that establish the commercial and economic centre based on the intensification of emperor's power by means of the organisation of ethical institution and the development of commercial economy. Firstly, the central place of the Kaifeng area is encircled with triple walls. This emphasise the authority of emperor located on the summit in the hierarchical ethic system succeeding to the main capital city plan of the late phase of ancient China. Secondly, the location of Dongjing Walled Town was decided by the transport network and the commercial function and defence function. Thirdly, this site shows the change of city structure and landscape of the Northern Song Dynasty. The closed Fengri (坊里: block) system transferred the open Jiexiang (街巷: road) system. Fourthly, the capital city was characterised by the free market trade and the diversification of market place. Fifthly, a convenient transport network in the Bian River, a centre of the Grand Canals, enabled to construct the Kaifeng Walled Town. Therefore, the Northern Song Dynasty continuously accomplished the developed water system as concerning about the utilisation of waterways after the construction of city.

• The Journal of Engineering Geology
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• v.29 no.2
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• pp.85-97
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• 2019

It can be observed that steep slopes ($65^{\circ}$ to $80^{\circ}$) consist of rock masses were kept stable for a long time. In rock-mass slopes with similar ground condition, steeper slopes than 1 : 0.5 ($63^{\circ}$) may be applied if the discontinuities of rock-mass slope are distributed in a direction favorable to the stability of the slope. In making a decision the angle of the slope, if the preliminary rock mass conditions applicable to steep slope are quantitatively setup, they may be used as guidance in design practice. In this study, the above rock mass was defined as a good continuum rock mass and the quantitative setup criterion range was proposed using RMR, SMR and GSI classifications for the purpose of providing engineering standard for good continuum rock mass conditions. The methods of study are as follows. The stable slope at steep slopes ($65^{\circ}$ to $80^{\circ}$) for each rock type was selected as the study area, and RMR, SMR and GSI were classified to reflect the face mapping results. The results were reviewed by applying the calculated shear strength to the stable analysis of the current state of rock mass slope using the Hoek-Brown failure criterion. It is intended to verify the validity of the preliminary criterion as a rock mass condition that remains stable on a steep slope. Based on the analysis and review by the above research method, it was analyzed that a good continuum rock mass slope can be set to Basic RMR ${\geq}50$ (45 in sedimentary rock), GSI and SMR ${\geq}45$. The safety factor of the LEM is between Fs = 14.08 and 67.50 (average 32.9), and the displacement of the FEM is 0.13 to 0.64 mm (average 0.27 mm). This can be seen as a result of quantitative representation and verification of the stability of a good continuum rock mass slope that has been maintained stable for a long period of time with steep slopes ($65^{\circ}$ to $80^{\circ}$). The setup guideline for a good continuum rock mass slope will be able to establish a more detailed setup standard when the data are accumulated, and it is also a further study project. If stable even on steep slopes of 1 : 0.1 to 0.3, the upper limit of steep slopes is 1 : 0.3 with reference to the overseas design standards and report, thus giving the benefit of ensuring economic and eco-friendlyness. Also, the development of excavation technology and plantation technology and various eco-friendly slope design techniques will help overcome psychological anxiety and rapid weathering and relaxation due to steep slope construction.

• Journal of Nutrition and Health
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• v.52 no.5
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• pp.435-448
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• 2019

Purpose: This study examined the changes in the nutrient intake and the prevalences of obesity and metabolic syndrome according to the eating alone behavior in middle-aged men and women. Methods: The data from the 2013 ~ 2017 Korean National Health and Nutrition Examination Survey were analyzed. A total of 7,728 adults (3,404 male, 4,324 female) aged 40 ~ 64 years old were included. The subjects were classified into three groups according to the number of times eating alone per day (0, 1 ~ 2, and 3 times/day). Dietary data were collected by a 1-day 24-h recall. The nutrient intakes were compared among the three groups. Survey logistic regression analyses were conducted to examine the association of the eating alone behavior with obesity and metabolic syndrome, adjusting for the related confounding variables. Results: In men, eating alone was associated significantly with a lower intake of potassium (p-for-trend = 0.048) and lower intake of calories from protein (p-for-trend = 0.04). In women, the proportion of subjects consuming energy less than 75% of the estimated energy requirement (p = 0.001) and less than the estimated adequate requirement of riboflavin (p < 0.001) differed significantly according to the eating alone behavior. The eating alone behavior was positively associated with an increased risk of developing metabolic syndrome (p-for-trend = 0.033), increased blood pressure (p-for-trend < 0.001), and increased waist circumference (p-for-trend = 0.004). On the other hand, in women, however, the eating alone behavior was associated with a decreased risks of developing obesity (p-for-trend = 0.02). No association was found between the eating alone behavior and the risk of metabolic syndrome in women. Conclusion: These results suggest that the eating alone behavior is a risk factor for the development of metabolic syndrome in middle-aged Korean men.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.210-220
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• 2019

Population growth and the increase of energy consumption due to civilization caused global warming. Temperature on the Earth rose about $0.7^{\circ}C$ for the last 100 years, the rate is accelerated since 2000. Temperature is a factor, which determines physiological action, growth and development, survival, etc. of the plant together with light intensity and precipitation. Therefore, it is expected that global warming would affect broadly geographic distribution of the plant as well as structure and function ecosystem. In order to understand the effect of global warming on the ecosystem, a study about the effect of temperature rise on germination and growth in the plant is required necessarily. This study was carried out to investigate the effects of experimental warming on the germination and growth of two oak species(Quercus mongolica and Q. serrata) in temperature gradient chamber(TGC). This study was conducted in control, medium warming treatment($+1.7^{\circ}C$; Tm), and high warming treatment ($+3.2^{\circ}C$; Th) conditions. The final germination percentage, mean germination time and germination rate of two oak species increased by the warming treatment, and the increase in Q. serrata was higher than that in Q. mongolica. Root collar diameter, seedling height, leaf dry weight, stem dry weight, root dry weight, and total biomass were the highest in Tm treatment. Butthey were not significantly different in the Th treatment. In the Th treatment, Q. serrata had significantly higher H/D ratio, S/R ratio, and low root mass ratio (RMR) compared with control plot. Q. mongolica had lower RMR and higher S/R ratio in the Tm and Th treatments compared with control plot. Therefore, growth of Q. mongolica are expected to be more vulnerable to warming than that of Q. serrata. The main findings of this study, species-specific responses to experimental warming, could be applied to predict ecosystem changes from global warming. From the result of this study, we could deduce that temperature rise would increase germination of Q. serrata and Q. mongolica and consequently contribute to increase establishment rate in the early growth stage of the plants. But we have to consider diverse variables to understand properly the effects that global warming influences germination in natural condition. Treatment of global warming in the medium level increased the growth and the biomass of both Q. serrata and Q. mongolica. But the result of treatment in the high level showed different aspects. In particular, Q. mongolica, which grows in cooler zones of higher elevation on mountains or northward in latitude, responded more sensitively. Synthesized the results mentioned above, continuous global warming would function in stable establishment of both plants unfavorably. Compared the responses of both sample plants on temperature rise, Q. serrata increased germination rate more than Q. mongolica and Q. mongolica responded more sensitively than Q. serrata in biomass allocation with the increase of temperature. It was estimated that these results would due to a difference of microclimate originated from the spatial distribution of both plants.