• Analytical Science and Technology
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• v.20 no.3
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• pp.227-236
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• 2007

This study was carried out to estimate the contents of heavy metals (Hg, Pb, and Cd) in seaweeds (n=169) which are closely related to food resources. The contents of heavy metals in the laver were found as follows; Hg was highly detected in the east coastal area ($0.0509{\pm}0.0635mg/kg$), Pb in the south coastal area ($0.0509{\pm}0.0635mg/kg$), Cd in the south coastal area ($1.3785{\pm}0.7754mg/kg$). In the sea mustard, Hg was highly detected in the south coastal area ($0.0152{\pm}0.0116mg/kg$), Pb in the east coastal area ($0.1633{\pm}0.2888mg/kg$), Cd in the south coastal area ($0.7141{\pm}0.4952mg/kg$). In the sea tangle, Hg was highly detected in the south coastal area ($0.0177{\pm}0.0118mg/kg$), Pb in the east coastal area ($0.0728{\pm}0.1025mg/kg$), Cd in the south coastal area ($0.1640{\pm}0.1253mg/kg$). In the sea lettuce, Hg, Pb, and Cd were highly detected from the west coastal area. In the fusiforme, Hg and Cd were highly in the west coastal area, Pb in the south coastal area. In general brown algae showed the highest level of Hg, Pb, and green algae showed the highest level of Cd Additionally, the significant correlation was observed between Hg and Cd (r=0.513, p<0.01), between Cd and Pb (r=0.420, p<0.05). The weekly average intakes of Hg, Pb and Cd from seaweeds takes about 0.17~10.30 % of PTWI (Provisional Tolerable Weekly Intakes) that FAO/WHO Joint Food Additive and Contaminants Committee has set to evaluate their safeties.

• Analytical Science and Technology
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• v.22 no.4
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• pp.336-344
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• 2009

This survey was carried out to estimate the contents of heavy metals (Hg, Pb, Cd, and As) in 10 kinds of dried marine products (n=189) which are closely related to food resources. The contents of heavy metals were estimated by inductively coupled plasma spectrometer (ICP) and mercury analyzer. The values of heavy metals in dried marine products were as follows (Mean${\pm}$SD (range), mg/kg). The average contents of heavy metals in the dried marine products were Hg $0.058{\pm}0.069$ (0.002~0.502) mg/kg, Pb $0.178{\pm}0.598$ (ND~5.130) mg/kg, Cd $0.306{\pm}0.610$ (ND~6.802) mg/kg, As $5.282{\pm}6.158$ (ND~71.760) mg/kg. The range of heavy metal contents in dried marine products are low level, except of lead contents (n=2). In the comparison of heavy metal content by anchovy size, it was shown that cadmium, mercury and arsenic were meaningfully different. The contents of heavy metals by the shape of shrimp and Alaska Pollack were shown that the result of each group was meaningless. In the comparison imported production with domestic production, in the case of common squid, cadmium and arsenic were meaningfully different. The weekly average intakes of Hg, Pb and Cd from dried marine products takes about 1.17~11.52% of PTWI (Provisional Tolerable Weekly Intakes) that FAO/WHO Joint Food Additive and Contaminants Committee has set to evaluate their safeties.

• The Korean Journal of Zoology
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• v.14 no.2
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• pp.57-74
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• 1971

The present investigation has been done to observe the ecological habits of field mice to protect the rice from damages during the growing season in paddy-field and during the storge period. The results obtained are summarized as follows: 1. Of 155 mice captured in the period of April-November 1970, which belong to four genera (Apodemus, Cricetulus, Rattus, and Micromys), 148 mice(95%) were found as striped field mice (Apodemus agrarius coreae). The population density of striped field mouse was revealed by the present study as 55/ha, which is quite a low level compared with that in Japan of 900/ha. 2. The age distribution of the mice as judged by their body weight was found mainly composed of adult and the sex ratio was found to be 1.8 as determined with 147 individuals. The nest was found to be occupied by an adult and was composed of at least three openings and more than one food storage tunnels. The mice usually keep hulled rice rather than unhulled one in storage tunnel. The weight of food found in a nest was about 50 grams on an average. 3. The mice show a most active behaviour 1-2 hours after the sunset, around midnight, and an hour before the sunrise, but they are active even in daytime in order for searching for food and for breeding. 4. The ratio (%) of damage appeared in high stem of sweet corn in August was 30 ~ 40 percent, whereas that in low stem was 80 ~ 90 percent. The weight of spoiled grains in paddy-field was 11, 400gm/0.4ha and this gives an estimate of 349, 695 for whole country. 5. The female striped field mouse weighs average of about 30 grams and gives birth to average of 4.8 younglings which wean away from female mouse three weeks after delivery. 6. The natural enemies to the mice are found to be carnivores (weasel, cat, mountain cat, fox, raccoon, and otter), raptatores(eagle, owl, kete, buzzard), and snakes. Two kinds of field rats(Rattus norvegicus, Cricetulus tritor) are also the predator to the mice. 7. The feeding preference of striped field mice follows in decreasing order of sweet corn, soybean, sweet potatoes, chestnut, and wheat. The mice do not have a preference for barley, millet, rough millet, red bean, and green bean. 8. The starvation experiment, in which water alone was supplied, revealed that the mice in good physical and nutritional conditions survived for 71 ~ 79 hours, whereas those in worse conditions survived for only 32 ~ 39 hours.

• Exercise Science
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• v.23 no.1
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• pp.1-11
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• 2014

The purpose of this study was to develop and validate regression models to estimate maximal oxygen uptake (VO₂max) from the 20 m Progressive Shuttle Run Test (20 m PSRT) in Korean middle-school girls aged 13-15 years. The 20 m PSRT and VO₂max were assessed in a sample of 194 participants. The sample was randomly split into validation (n=127) and test-retest reliability (n=99, 32 out of 127 participants also performed validity test) groups. 127 participants performed a graded exercise test (GXT, stationary gas analyser) and the 20 m PSRT (portable gas analyser) once to develop a VO₂max prediction model and to analyze the validity of the modified 20 m PSRT protocol (starting at 7.5 km/h and increasing by 0.5 km/h every 1 min). 99 participants performed the 20 m PSRT twice for test-retest reliability purpose. Mean measured VO₂max (39.2±5.1 ml/kg/min) from the potable gas analyzer was significantly increased from that measured during the GXT from stationary gas analyzer (37.7±5.7 ml/kg/min, p=.001) using the modified 20 m PSRT protocol. But it was a narrow range (1.5 ml/kg/min). The measured VO₂max from the potable and stationary gas analyzers correlated at r=.88(p<.001). Test-retest of the 20 m PSRT yielded comparable results (Laps r=.88 & final speed r=.85). New regression equations were developed from present data to predict VO₂max for middle-school girls: y=.231×Laps-.311×weight(in kg)+46.201 (r=.74, SEE=4.29 ml/kg/min). It is concluded that (a) the modified 20 m PSRT protocol is a valid and reliable test and (b) this equation developed in this study provides valid estimates of VO₂max of Korean middle-school girl aged 13-15 years.

• Korean Journal of School Psychology
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• v.15 no.3
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• pp.459-488
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• 2018

The self-report assessment has been most commonly used to estimate bullying/victimization (B/V) rates in most domestic and international prevalence studies. However, the presence of many potential biasing factors in such an assessment method, including specific operationalization/measurement strategies and testing conditions, has become an issue due to a considerable variability in reported involvement rates across studies. This study analyzed self-reported B/V involvement rates on Olweus Bullying Questionnaire (OBQ) among 690 Korean middle school students by gender and two different cut-offs (generous vs. strict cut-offs) and examined if the involvement rates were significantly varied by testing conditions such as presentation vs. omission of a precise definition of B/V, anonymous vs. non-anonymous/confidential administration, and the use of global vs. specific questions. Chi-square analyses revealed that boys displayed higher involvement rates on global measures of B/V and on items related to direct forms of B/V, with no significant gender differences on specific measures of relational B/V rates. It was also found that a global rate of bullying and specific rates of verbal B/V were 111% to 157% higher when no definition was provided. However, anonymous vs. non-anonymous administration had no significant impacts on rates of involvement, except for one item; there were also no significant differences in reported degrees of frankness and perceived confidentiality of their responses across two adminstration conditions. Finally, when involvement rates were assessed by using specific vs. global items, they were 68% to 148% higher with binominal correlations in low to moderate ranges. Findings also indicated that global items had a high specificity but a relatively low sensitivity. Implications of these findings were fully discussed for researchers and practitioners in the field of B/V assessment.

• (The) Research of the performance art and culture
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• no.23
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• pp.63-103
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• 2011

This paper inquires closely into the background of pansori gosu(drummer) and his social position based on documents and oral materials and the performance features of gosu in the entire process of pansori performance, 'preparation', 'performance' and 'aftermath', focused on the relationship between the changja(singer)-gosu. In the past, some gosus were ex-tightrope performers. Their social position and working conditions were better than that of the ex-tightrope performers but were worse than that of the pansori singer. After 1910's, people formed some special sense about the gosu due to the change of the space for pansori performances and the technological advances on the media, and gosu's conditions improved. The theory of pansori drum gradually began to be established well. The function and the role of gosu in the whole process of pansori performance may be summarized as follows. To begin with, the training with various and a lot of singers is required in the 'preparation'. Rehearsals are divided into individual practices and joint practices, and the latter can be controlled by the level of the capacity of gosu and the degree of the experience between chanja-gosu. Next, bobiwi(flattering drumming) and chuimsae(encouraging remarks) are important in tbe 'process'. The gosu has to share the speed of one jangdan(rhythmic patterns) and the accent of the sori and adjust his enery. Besides, he has to acknowledge the naedeureum(beginning sign) and reply with changja's singing. In formal performances, working in harmony with changja and gosu and their joint experiences are necessary for the gosu; in pansori contests, giving chanja a stability; in contests for gosu, drumming skill, position, chuimsae; in small performances and new adaptation of pansori, cheap fees and positive response of the transformational play or ad-lib; in lecturer concerts, reacting quickly to rapidly changing situations. Chuimsae is way which gosus and audiences express their feeling together, however, its context and sound are different. Finally, 'aftermath' is a process the pair of chamgja and gosu mutually evaluates about performance or audiences estimate that.

• Korean Journal of Culture and Social Issue
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• v.25 no.2
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• pp.101-118
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• 2019

Alexithymia refers to a psychological deficit of identifying and describing one's feelings. It has benn reported that the level of alexithymia of East-Asians is generally higher than that of Western Europeans. Recently one research conducted in U.S. suggested that the interdependent self-construal from East-Asians' collectivism culture might be a cause of this cross-cultural difference. In the current study, we examined the relationship between the level of independent and interdependent self-construal of Korean college students and their level of alexithymia, as well as their ambivalence over emotional expressiveness and emotion suppression. The correlation analysis shows that the Korean students' alexithymia level does not correlate with their level of interdependent self-construal, but negatively correlates with their level of independent self-construal. Moreover, it is also correlated with the level of ambivalence over emotional expressiveness(AEE) and emotion suppression(ES). Thus, we setup a double-mediation model between the deficiency of independent self-construal and alexithymia via AEE and ES, and estimate mediation effects using Hayes and Preacher(2014)s' Process analysis. The results show that the deficiency of independent self-construal has a direct effect as well as indirect effects of AEE and ES on the alexithymia level. Further analysis on the indirect effects reveals that the mediation effect of AEE and the double mediation effect of ES via AEE are significant, but the mediation effect of ES is not significant. Current results imply that the interdependent self-construal from the traditional collectivistic culture may not cause Korean college students' problems on the emotional expression, but the relatively lower independent self-construal may cause them. The deficiency of independent self-constural may raise up the level of self-defensive ambivalence over emotional expressiveness and suppress emotional expression by themselves, which can result in alexithymia.

• Journal of Wetlands Research
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• v.25 no.4
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• pp.297-305
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• 2023

The recycled irrigation is a type of irrigation that uses downstream water to fulfill irrigation demand in the upstream agricultural areas; the used irrigation water returns back to the downstream. The recycled irrigation is advantageous for securing irrigation water for plant growth, but the returned water typically contains high levels of nutrients due to excess nutrients inputs during the agricultural activities, potentially deteriorating stream water quality. Therefore, quantitative assessment on the effect of the recycled irrigation on the stream water quality is required to establish strategies for effective irrigation water supply and water quality management. For this purpose, a watershed model is generally used; however no functions to simulate the effects of the recycled irrigation are provided in the existing watershed models. In this study, we used multi-reservoir model coupled with the Hydrological Simulation Program-Fortran (HSPF) to estimate the effect of the recycled irrigation on the stream water quality. The study area was the Gwangok stream watershed, a subwatershed of Gyeseong stream watershed in Changnyeong county, Gyeongsangnam-do. The HSPF model was built, calibrated, and used to produce time series data of flow and water quality, which were used as hypothetical observation data to calibrate the multi-reservoir model. The calibrated multi-reservoir model was used for simulating the recycled irrigation. In the multi-reservoir model, the Gwangok watershed consisted of two subsystems, irrigation and the Gwangok stream, and the reactions (plant uptake, adsorption, desorption, and decay) within each subsystem, and fluxes of water and materials between the subsystems, were modeled. Using the developed model, three scenarios with different combinations of the operating conditions of the recycled irrigation were evaluated for their effects on the stream water quality.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.337-345
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• 2023

Estimating the rice heading date is one of the most crucial agricultural tasks related to productivity. However, due to abnormal climates around the world, it is becoming increasingly challenging to estimate the rice heading date. Therefore, a more objective classification method for estimating the rice heading date is needed than the existing methods. This study, we aimed to classify the rice heading stage from various images using a CNN classification model. We collected top-view images taken from a drone and a phenotyping tower, as well as slanted-view images captured with a RGB camera. The collected images underwent preprocessing to prepare them as input data for the CNN model. The CNN architectures employed were ResNet50, InceptionV3, and VGG19, which are commonly used in image classification models. The accuracy of the models all showed an accuracy of 0.98 or higher regardless of each architecture and type of image. We also used Grad-CAM to visually check which features of the image the model looked at and classified. Then verified our model accurately measure the rice heading date in paddy fields. The rice heading date was estimated to be approximately one day apart on average in the four paddy fields. This method suggests that the water head can be estimated automatically and quantitatively when estimating the rice heading date from various paddy field monitoring images.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.267-275
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• 2023

This study predicted rice harvest date in South Korea using 11-year (2012-2022) hindcasts based on dynamically downscaled 2m air temperature at subseasonal (1-month lead) timescale. To obtain high (5 km) resolution meteorological information over South Korea, global prediction obtained from the NOAA Climate Forecast System (CFSv2) is dynamically downscaled using the Weather Research and Forecasting (WRF) double-nested modeling system. To estimate rice harvest date, the growing degree days (GDD) is used, which accumulated the daily temperature from the seeding date (1 Jan.) to the reference temperature (1400℃ + 55 days) for harvest. In terms of the maximum (minimum) temperatures, the hindcasts tends to have a cold bias of about 1. 2℃ (0. 1℃) for the rice growth period (May to October) compared to the observation. The harvest date derived from hindcasts (DOY 289) well simulates one from observation (DOY 280), despite a margin of 9 days. The study shows the possibility of obtaining the detailed predictive information for rice harvest date over South Korea based on the dynamical downscaling method.