• Title/Summary/Keyword: value of time

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Persistence of Fungicide Pencycuron in Soils (토양 중 살균제 Pencycuron의 잔류 특성)

  • An, Xue-Hua;An, Wen-Hao;Im, Il-Bin;Lee, Sang-Bok;Kang, Jong-Gook
    • The Korean Journal of Pesticide Science
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    • v.10 no.4
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    • pp.296-305
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    • 2006
  • The adsorption and persistence of pencycuron {1-(4-chlorobenzyl) cyclopentyl-3-phenylurea} in soils were investigated under laboratory and field conditions to in order to assess the safety use and environmental impact. In the adsorption rate experiments, a significant power function of relation was found between the adsorbed amount of pencycuron and the shaking time. Within one hour following the shaking, the adsorption amounts in the SCL and the SiCL were 60 and 65% of the maximum adsorption amounts, respectively. The adsorption reached a quasi-equilibrium 12 hours after shaking. The adsorption isotherms followed the Freundlich equation. The coefficient (1/n) indicating adsorption strength and degree of nonlinearity was 1.45 for SCL and 1.68 to SiCL. The adsorption coefficients ($K_d$) were 2.31 for SCL and 2.92 to SiCL, and the organic carbon partition coefficient, $K_{oc}$, was 292.9 in SCL and 200.5 inSiCL. In the laboratory study, the degradation rate of pencycuron in soils followed a first-order kinetic model. The degradation rate was greatly affected by soil temperature. As soil incubation temperature was increased from 12 to $28^{\circ}C$, the residual half life was decreased from 95 to 20 days. Arrhenius activation energy was 57.8 kJ $mol^{-1}$. Furthermore, the soil moisture content affected the degradation rate. The half life in soil with 30 to 70% of field moisture capacity was ranged from 21 to 38 days. The moisture dependence coefficient, B value in the empirical equation was 0.65. In field experiments, the half-life were 26 and 23 days, respectively. The duration for period of 90% degradation was 57 days. The difference between SCL and SiCL soils varied to pencycuron degradation rates were very limited, particularly under the field conditions, even though the characteristics of both soils are varied.

Significance of Apoptotic Cell Death after $\gamma-Irradiation$ (방사선 조사에 의한 세포사에 있어서 세포고사의 의미)

  • Wu H.G.;Kim I.H.
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.252-258
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    • 2001
  • Purpose : The objectives of this study are to investigate the significance of apoptotic death compared to total cell death after $\gamma-ray$ irradiation in human H&N cancer cell lines and to find out correlation between apoptosis and radiation sensitivity. Materials and method : Head and neck cancer cell lines (PCI-1, PCI-13, and SNU-1066), leukemia cell line (CCRF-CEM), and fibroblast cell line (LM217) as a normal control were used for this study. Cells were irradiated using Cs-137 animal experiment irradiator. Total cell death was measured by clonogenic assay. Annexin-V staining was used to detect the fraction of apoptotic death. Results : Surviving fraction at 2 Gy (SF2) were 0.741, 0.544, 0.313, 0.302, and 0.100 for PCI-1, PCI-13, SNU-1066, CCRF-CEM, and LM217 cell lines, respectively. Apoptosis was detected in all cell lines. Apoptotic index reached peak value at 72 hours after irradiation in head and neck cancer cell lines, and that was at 24 hours in CCRF-CEM and LM217. Total cell death increased exponentially with increasing radiation dose from 0 Gy to 8 Gy, but the change was minimal in apoptotic index. Apoptotic fractions at 2 Gy were $46\%,\;48\%,\;46\%,\;24\%,\;and\;19\%$ and at 6 Gy were $20\%,\;33\%,\;35\%,\;17\%,\;and\;20\%$ for PCI-1, PCI-13, SNU-1066, CCRF-CEM, and LM217, respectively. The radioresistant cell lines showed more higher apoptotic fraction at 2 Gy, but there was not such correlation at 6 Gy. Conclusion : All cell lines used in this study showed apoptosis after irradiation, but time course of apoptosis was different from that of leukemia cell line and normal fibroblast cell line. Reproductive cell death was more important mode of cell death than apoptotic death in all cell lines used in this study. But there was correlation between apoptotic fraction and radiation sensitivity at 2 Gy.

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Analysis of comparisons of eating-out, dietary lifestyles, and healthy dietary competencies among middle-aged consumers according to obesity status and gender for implications of consumer education (소비자교육을 위한 중년기 소비자의 성별, 비만도별 외식 행동, 식생활 라이프스타일 및 건강한 식생활역량의 차이 분석)

  • Park, Jong Ok
    • Journal of Nutrition and Health
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    • v.51 no.1
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    • pp.60-72
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    • 2018
  • Purpose: The purpose of this study was to determine differences in eating-out, dietary life styles, and healthy dietary competencies among middle-aged consumers according to obesity status and gender for implications of consumer education. Methods: Data were drawn from the 2016 Food Consumption Behavior Survey, and 3,022 subjects (mail 1,388; female 1,634) who were middle-aged adults were investigated. Analysis of variance with $Scheff\acute{e}$ test, t-test, $x^2$-test, and factor analysis were performed using SPSS v.24. Results: Males showed less interest in diet than females. For both males and females, higher BMI degrees were associated with higher levels of interest in diet. For frequency, monthly average consumption expenditure, one-time cost for eating out, and drinking frequency, males showed higher levels than females. Especially for the male group, higher obesity status was associated with higher levels of eating out and drinking. Dietary lifestyles of males and females turned out to be very similar. For the male group, normal weight group was more likely to show 'health and high quality pursuit dietary life-style' than the other groups. For females, the normal weight group were more likely to show 'health and high quality pursuit dietary life-style' and 'safety pursuit dietary life-style' than the other groups. The level of 'healthy dietary competence' for females was found to be higher than that for males. For the female group, there were significant differences according to obesity status, and practice was more important than knowledge in determining a healthy dietary life. Conclusion: For dietary life-related education for obese middle-aged consumers, it is important to emphasize less eating-out and drinking and less overeating while eating-out based on the results that eating-out, drinking, and overeating in the obesity group were significantly higher than in the normal group. It is important to focus on the value of dietary life and diverse foods, based on the results that the obesity group was less likely to be have healthy dietary lifestyles and consume less diverse foods than the normal group.

A Study on Documentation Strategy for Archiving Locality (지역 아카이빙을 위한 기록화방안 연구)

  • Kwon, Soon-Myung;Lee, Seung-Hwi
    • The Korean Journal of Archival Studies
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    • no.21
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    • pp.41-84
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    • 2009
  • Lots of cultures, memories, histories of the local life have disappeared. Some sectors of universities and religion have keep their records in manuscript archive only. On the other hand records of public sectors were at least able to be managed by the records management law. Citizen's groups and academic bounds were also roles to get public records strong. However can we just describe whole body with only public records? As records management law a record of private sector which has value of preserving can be managed under national protection. Yet establishment of local archive is not obligate. Only stressing on public records is like what dictatorial government acted in past years. It is what we ignore diversity and request of community. We need to move our view that we have focused on public and central sectors to private and local sectors. Local records management based on locality could help to complete the entire puzzle. The way complete the puzzle is various and wide spheres including from cultural space to being extinct village. Locality is defined as the property in certain area or distinctiveness of locals. Establishing production strategies is as important as collecting records produced over the past years for local archiving. Local archiving has to be regionally conducted in phase. Moreover common wealth and recognition of communities are reflected in the acquisition process. In next to archiving local organizations and private records according to collection policy, methodology on local archiving needs for archive management and use in various public and private fields. This methodology could be possible by building a local archive networking tool. It is true that Local archiving is not familiar and clear yet. If we can turn the effort for public records we have made to endeavor for private sectors, we might expect big fruits in private sectors. We easily emphasis on globalization or internationalization, our daily lives start on our villages. Setting aside our small communities, such a puzzle of the whole would never be completed. This is good time to begin finding lost puzzle for future. The key that can find lost puzzles be held in archiving localities.

Predicting Crime Risky Area Using Machine Learning (머신러닝기반 범죄발생 위험지역 예측)

  • HEO, Sun-Young;KIM, Ju-Young;MOON, Tae-Heon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.21 no.4
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    • pp.64-80
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    • 2018
  • In Korea, citizens can only know general information about crime. Thus it is difficult to know how much they are exposed to crime. If the police can predict the crime risky area, it will be possible to cope with the crime efficiently even though insufficient police and enforcement resources. However, there is no prediction system in Korea and the related researches are very much poor. From these backgrounds, the final goal of this study is to develop an automated crime prediction system. However, for the first step, we build a big data set which consists of local real crime information and urban physical or non-physical data. Then, we developed a crime prediction model through machine learning method. Finally, we assumed several possible scenarios and calculated the probability of crime and visualized the results in a map so as to increase the people's understanding. Among the factors affecting the crime occurrence revealed in previous and case studies, data was processed in the form of a big data for machine learning: real crime information, weather information (temperature, rainfall, wind speed, humidity, sunshine, insolation, snowfall, cloud cover) and local information (average building coverage, average floor area ratio, average building height, number of buildings, average appraised land value, average area of residential building, average number of ground floor). Among the supervised machine learning algorithms, the decision tree model, the random forest model, and the SVM model, which are known to be powerful and accurate in various fields were utilized to construct crime prevention model. As a result, decision tree model with the lowest RMSE was selected as an optimal prediction model. Based on this model, several scenarios were set for theft and violence cases which are the most frequent in the case city J, and the probability of crime was estimated by $250{\times}250m$ grid. As a result, we could find that the high crime risky area is occurring in three patterns in case city J. The probability of crime was divided into three classes and visualized in map by $250{\times}250m$ grid. Finally, we could develop a crime prediction model using machine learning algorithm and visualized the crime risky areas in a map which can recalculate the model and visualize the result simultaneously as time and urban conditions change.

A study on the modernization of 'Kokdugaksinorum' (<꼭두각시놀음>의 현재화 방안 연구 - 극단 '사니너머'의 <돌아온 박첨지 시즌2>를 중심으로 -)

  • Choe, Yunyoung
    • (The) Research of the performance art and culture
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    • no.32
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    • pp.71-106
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    • 2016
  • This study analyzes the current work of the traditional theater around 'Back Parkcheomji(season2)' of theatre troupe 'Saninomou'. 'Back Parkcheomji(season2)' has proved that it is possible modernization while at the same time preserving the traditional theater. As a result, 'Back Parkcheomji(season2)' regained the spirit of contemporary social criticism and reality inherent in Kokdugaksinorum. The performance are beyond the traditional production method, which has created a new performance aspects. 'Back Parkcheomji(season2)' has created the puppets like this 'Kimga' 'Seweolho' 'Ryukbang' 'Chourani'. Traditional and creative dolls has criticized our modern society at the same stage. On the other hand, plays such as tightrope, Pungmul, Burna confirmed the spirit of Namsadangpae, and gave a dramatic fun. 'Back Parkcheomji(season2)' has dual stage. The dual stage will produce a magnificent spectacle, and has provided a variety of attractions. 'Back Parkcheomji(season2)' re-created the traditional theater of Namsadangpae in vivid contemporary version. The performance has made the opportunity to think again about the value of classical and allowed to recognize the new phase of classical theater.

Biochemical Methane Potential Analysis of Mushroom Waste Medium (버섯 폐배지의 생화학적 메탄퍼텐셜 분석)

  • Kim, Chang-Gyu;Lee, Jun-Hyeong;Yoon, Young-Man
    • Journal of the Korea Organic Resources Recycling Association
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    • v.30 no.1
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    • pp.13-21
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    • 2022
  • Mushroom waste medium refers to the waste biomass generated after mushroom cultivating. And, the burden of treatment on mushroom farmhouse is increasing due to the absence of appropriate treatment method and increase of treatment costs of the mushroom waste medium. In this study, in order to assess the energy value of mushroom waste medium by an anaerobic digestion, methane potential and anaerobic organic matter decomposition characteristics were investigated. The theoretical methane potential(Bth) of mushroom medium(MM) was 0.481 Nm3-CH4/kg-VSadded, and the Bth of mushroom waste medium(MWM) was 0.451 Nm3-CH4/kg-VSadded. The biochemical methane potential(Bu-exp) of MWM was increased by 18% from 0.155 for MM to 0.183 Nm3-CH4/kg-VSadded for MWM. In the reaction kinetics analysis by the Modified Gompertz model, the maximum methane production rate(Rm) was increased from 4.59 for MM to 7.21 mL/day for MWM and the lag growth phase time(λ) was decreased from 2.78 for MM to 1.96 days for MWM. In the reaction kinetics analysis by the parallel first order kinetics model, the easily degradable organic matter(VSe) content was increased by 5.89% and the persistently degradable organic matter(VSp) content was 2.03% in MWM, and the non-degradable organic matter(VSNB) content was decreased by 7.85%. Therefore, it was evaluated that the anaerobic digestion efficiency of MWM was increased. The anaerobic digestion efficiency of MWM was assessed to be more improved than that of MM.

Changes in Teaching Practices of Elementary School Teachers in Scientific Modeling Classes: Focused on Modeling Pedagogical Content Knowledge (PCK) (과학 모델링 수업에서 나타난 초등 교사의 수업 실행 변화 -모델링 PCK를 중심으로-)

  • Uhm, Janghee;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
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    • v.40 no.5
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    • pp.543-563
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    • 2020
  • This study explores how the teaching practices of two teachers changed during scientific modeling classes. It also aims to understand these changes in terms of the teachers' modeling pedagogical content knowledge (PCK) development. The study participants were two elementary school teachers and their fifth-grade students. The teachers taught eight lessons of scientific modeling classes about the human body. The data analysis was conducted for lessons 1-2 and 7-8, which best showed the change in teaching practice. The two teachers' teaching practices were analyzed in terms of feedback frequency, feedback content, and the time allocated for each stage of model generation, evaluation, and modification. Teacher A led the evaluation and modification stages in a teacher-driven way throughout the classes. In terms of feedback, teacher A mainly used answer evaluation feedback in lesson 1-2; however, in lesson 7-8, the feedback content changed to thought-provoking feedback. Meanwhile, teacher B mostly led a teacher-driven model evaluation and modification in lesson 1-2; however, in lesson 7-8, she let her students lead the model evaluation and modification stages and helped them develop models through various feedbacks. The analysis shows that these teaching changes were related to the development of modeling PCK components. Furthermore, the two teachers' modeling PCK differed in teaching orientation, in understanding the modeling stages, and in recognizing the value of modeling, suggesting the importance of these in modeling teaching practice. This study can help improve the understanding of modeling classes by revealing the relationship between teaching practices and modeling PCK.

Management Strategy of Indoor Hazardous Chemicals (실내.외 통합 모델링 및 인체 위해성 평가를 통한 실내 유해화학물질의 관리 전략)

  • Shin, Yong-Seung;Lim, Hye-Sook
    • Journal of Environmental Policy
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    • v.7 no.2
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    • pp.67-90
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    • 2008
  • The purpose of this study is to develop indoor air quality management strategies regarding indoor air pollutants while considering various factors affecting indoor pollutants concentration. The Integrated Indoor Air Quality model(IIAQ) developed by Seoul National University is used for this study. The IIAQ model is a tool that can provide an integrated view to indoor environmental pollution by simulating suggested scenarios. The results of the modeling are used to assess health risk. The concentrations that are used for the risk characterization are weighted concentrations based on the period of time in each place and existing Indoor Air Quality(IAQ) standards. The estimated concentration of toluene and formaldehyde for 10 years through the IIAQ model was 207.3 $ug/m^3$ and 36.4 $ug/m^3$ in indoors, and 55.9 $ug/m^3$ and 8.62 $ug/m^3$ in outdoors. These concentrations are lower than the existing IAQ standards. The estimated carcinogenic risk of formaldehyde is up to 1.05E-03 for the adult male group and exceeds 1E-06 for all receptor groups. This value means that cancer could affect one person out of 1000. The estimated non-carcinogenic risk of toluene was lower than 1, which means that there was no serious non- carcinogenic risk. The result of modeling shows that using low emitting indoor sources is the most effective strategy for both formaldehyde and toluene. This risk assessment suggests that the total exposure levels of existing IAQ standards may cause serious carcinogenic risk. In order to avoid uncontrolled risk, it is suggested that the current IAQ standards should be adjusted by taking into account the total amount of exposure from all exposure pathways from indoor and outdoor sources.

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Studies on the Improvement of Mountainous Pasture III. Effect of seed coating on oversown pasture (산지초지 개량에 관한 연구 III. 종자 Coating에 의한 겉뿌림 초지육성)

  • 이인덕
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.4 no.3
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    • pp.194-200
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    • 1984
  • Effects of seed coating on establishment, early growth and herbage production were investigated in Pot, Soil box and Field experiments. Seed was coated with 60% Lime, 20% Phosphate and 20% Peatmoss(W/W), also finely sprayed 13% Arabic gum and 2% Methyl cellulose(W/V). Coating were generally 1:20, seed: coat(W/W). 1. In the general growth of the growing stages and different oversown species at 80 days, seed coated was promoted than none in early growth. (Table 2 and 3) 2. Stand counts at 60 days after oversown, seed coated was higher 15% than none, especially, there was advantage due to coating on the medium and large size seeds such as Orchardgrass, Perennial ryegrass and Kentucky bluegrass, but did not assist establishment of the large (Tall fescue) and small (Ladino clover) size seed. 3. Variation of sward composition was not quite different between two treatments, but seed coated was slightly increased the Percentage of sown grasses with advance of cutting time. 4. Total dry metter yield per unit area with seed coated was higher 17% than none in establishment year. 5. Variations in the chemical composition of the herbage and soil were influenced by coating materials in the coating regime (Table 8). 6. From these facts, seed coated also appeared that adequate seedling stands, early growth and herbage production could be obtained with higher than conventional overseeding method under a poor conditions.

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