• Title/Summary/Keyword: scale effects

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Evaluating the Performance of APEX-Paddy Model using the Monitoring Data of Paddy Fields in Iksan, South Korea (국내 논필지 모니터링 자료를 이용한 APEX-Paddy 모델 적용성 평가)

  • Kamruzzaman, Mohammad;Cho, Jaepil;Choi, Soon-Kun;Song, Jung-Hun;Song, Inhong;Hwang, Syewoon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.1
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    • pp.1-16
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    • 2020
  • The APEX model has been developed for assessing agricultural management efforts and their effects on soil and water at the field scale as well as more complex multi-subarea landscapes, whole farms, and watersheds. Recently, a key component of APEX application, named APEX-Paddy, has been modified for simulating water quality by considering paddy rice management practices. In this study, the performance of the APEX-Paddy model was evaluated using field data at Iksan experimental paddy sites in Korea. The discharge and pollutant load data during 2013 and 2014 were used to both manually and automatically calibrate the model. The APEX auto-calibration tool (APEX-CUTE 4.1) was used for model calibration and sensitivity analysis. Results indicate that APEX-Paddy reasonably performs in predicting runoff discharge rate and nitrogen yield. However, sediment and phosphorus yield is not correctly predicted due to the limitation of model schemes. With APEX-Paddy, the performance in reproducing the discharge and nitrogen yield is found to be a satisfactory level after manual calibration. The manually calibrated model performed better than the automatically calibrated model in nearly all comparisons. For runoff, manual calibration reduced PBIAS while R2 and NSE values of the automatically calibrated model were the same as the manual calibration. For T-N, NSE and PBIAS were reduced when using manual calibration, whereas R2 value was the same as manual calibration. The limitation of the APEX-Paddy model for predicting sediment, as well as the phosphorous yield, was discussed in this study.

Preliminary study on geochemical elements concentration changes in coral skeleton from Chuuk, Micronesia (마이크로네시아 축 경산호 골격의 지화학 원소 농도에 대한 예비연구)

  • Hyun, Sang-Min;Park, Heung-Sik;Kim, Su-Hyun;Kim, Han-Jun;Jang, Suk
    • The Korean Journal of Quaternary Research
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    • v.22 no.1
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    • pp.1-12
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    • 2008
  • We investigated metal concentrations and oceanic environment changes that have occurred over the past several years by studying the hard coral Porites lutea, which inhabits tropical and subtropical areas. Soft X-radiographs clearly showed distinctive annual bands within 71 mm coral sample, which reflect changes in the oceanic environment over this period. There were large fluctuations in the major and minor element concentrations. Considering the physicochemical partition coefficient, some elements accumulated in the aragonite matrix in a mechanical manner, while others were affected by environmental factors. The concentrations of some heavy metals varied over a wide range, implying local environmental effects. The variation of Sr/Ca and Mg/Ca in coral skeleton clearly showed large-scale fluctuation over the specific intervals, implying environmental changes during this period. The concentrations of heavy metals also show high fluctuations, and roughly accord with Mg/Ca variation. In addition, Cu and Zn seem to show cyclicity-like peaks, coincide with Mg/Ca variation over the specific intervals. Such variation might be related to local pollution and oceanographic changes. More detailed investigation is necessary, including the pretreatment of coral skeleton sediment.

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A Discourse Analysis of Attempts to Strengthen Global Image through the 2011 World Athletics Championships (스포츠 관광을 통한 대구의 세계화 - 2011 대구세계육상선수권대회의 문화지리학적 분석 -)

  • Ethan, Yorgason
    • Journal of the Korean association of regional geographers
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    • v.19 no.3
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    • pp.454-475
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    • 2013
  • In 2011, Daegu hosted the International Association of Athletics Federation Championships and attempted to use this event strengthen its global profile. Organizers hoped Daegu 2011 would strengthen knowledge about Daegu internationally and help the city overcome recent economic stagnation by bolstering tourism and investment on the global scale. Written from the perspective of a foreigner living in Korea, this interpretive article uses mixed-method cultural geographic analysis to evaluate the momentum Daegu 2011 produced in these directions. The article draws on a tripartite "territorialisation" approach to mega-event tourism's production of space, focusing on representational efforts during the approach to the championships and the event itself. Promotional materials receive particular attention. Interviews with international tourists during 2011 strengthen conclusions drawn from analysis of promotional materials. After reviewing relevant conceptual literature, Daegu's history, and the background of Daegu 2011, the article devotes three subsections to analysis. The first uses critical discourse analysis of a key promotional video to argue that Daegu's self-promotions betrayed insecurity about the city's place within the global tourism market. A second analysis subbsection finds that additional promotional materials did not fully overcome that problem. These materials also produced an overload of Daegu images and aspirations. The third subsection further develops these arguments, pointing to a partial mismatch between images emphasized by promotions and experiences available in the tourism landscape. This subsection also argues that while Daegu 2011 undoubtedly produced positive effects for the city, key challenges remain if Daegu will be placed on the map of globally acknowledged cities.

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Studies on the Thermal and Rheological Properties of Polypropylene/Starch-MB Blends (폴리프로필렌/옥수수전분 블렌드의 열적 유변학적특성 연구)

  • Kim, Youn Cheol;Lee, Chang-Young
    • Applied Chemistry for Engineering
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    • v.18 no.6
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    • pp.557-561
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    • 2007
  • Polypropylene (PP)/corn starch master batch (starch-MB) blends with different PP compositions of 40, 50, 60, and 80 wt% were prepared by melt compounding at $200^{\circ}C$, using lab scale Brabender mixer. The chemical structures and thermal properties of the PP/starch-MB blends were investigated by FT-IR, differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA). The chemical structure was confirmed by the existence of hydroxy group. There was no district change in melting temperature and melting enthalpy, and TGA curve indicated a decrease in degradation temperature with starch-MB content. The porosity change of blend was measured by scanning electron microscope (SEM), the degree of porosity on the blend surface increased with the starch-MB content. The rheological properties indicated an increase in complex viscosity, shear thinning tendency and elasticity with the starch-MB concentration. These effects were confirmed by an oscillatory viscometer at $200^{\circ}C$. From these results, it is found that 40 wt% is the optimum starch-MB concentration. The fiber was fabricated from PP60/MB40 with 40 wt% starch-MB and the porosity and tensile properties were investigated.

Effects of Egg White Manufacturing Conditions on the Physicochemical and Sensory Properties of Angel Food Cakes (난백분말 제조 조건에 따른 엔젤 푸드 케이크의 특성 변화)

  • Yang, Hae-Young;Kim, Min-Young;Kim, Jeong-Yeon;Shim, Jae-Yong;Imm, Jee-Young;Park, Ki-Hwan
    • Korean Journal of Food Science and Technology
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    • v.41 no.2
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    • pp.167-172
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    • 2009
  • The principal objective of this study was to determine the optimum manufacturing conditions of egg white with high foaming property for the production of angel food cakes. The egg whites were desugarized and powdered at predetermined pHs and drying temperatures. The physicochemical properties of the produced cakes were measured and sensory evaluations were conducted on a 9-point scale. The volume and textural properties of cakes produced from spray-dried egg whites did not differ from those of the cakes prepared from the control egg whites. The pH of batter and the specific gravity of foam and batter with egg white powder at pH 6.74/66.5$^{\circ}C$ did not differ from those of the control, whereas the one prepared with commercial powder lost the characteristics of cake to a significant degree. The overall acceptance scores of egg white powder of pH 6.74/66.5$^{\circ}C$ and commercial powder were 6.25 and 2.33 as compared to the control (6.42). These results indicate that the egg white powder that was desugarized, pH-adjusted to 6.74, and dried at 66.5$^{\circ}C$ might be utilized to prepare angel food cakes with the desirable physicochemical and sensory attributes.

The Effect of Middle Schoolers' Oral Health Awareness on Oral Health Condition and Oral Health Behavior (중학생들의 구강보건인식이 구강건강상태와 구강건강행위에 미치는 영향)

  • Cho, Eun-Suk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.5020-5028
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    • 2013
  • The purpose of this study is to investigate the effects of awareness of oral health on oral health status and oral health behavior with subjects of students in the middle school which is the important period when lifetime set of teeth is completed with eruption of the second molar tooth and complete set of permanent teeth, and provide the basic data for development of oral health program for adolescents. We examined oral condition and conducted the survey about students' awareness of oral health and behavior in the middle school located in JeonJu. As the results of oral examination, dental caries and malocclusion were higher in female students and periodontal disease was higher in male students (p < 0.038). There was no significant difference in awareness of oral health between male and female students. However, M = 4.08 out of 5 point scale, which was high. For oral health behaviors, female students (M = 4.508) was higher than male students (M = 4.257) in the question of 'I visit the dental office when my gums are bleeding'. Female students (M = 4.547) was higher than male students (M = 4.333) in the question of 'I use the dental floss after brushing my teeth'(p<0.05). Awareness of oral health gave the significant effect on the oral health behavior at 95 % confidence level. Therefore, the education for oral health behavior is required to improve oral health and studies are needed to present the development of program for awareness and knowledge of oral health affecting behavior.

A study on the Improvement Method of the Report and Reward System on an Illegal Behavior of the Emergency Exit (비상구 불법행위 신고포상제도의 개선방안에 관한 연구)

  • Kim, Myeong Sik;Lee, Tae Shik;Cho, Won Cheol
    • Journal of Korean Society of Disaster and Security
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    • v.5 no.2
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    • pp.49-59
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    • 2012
  • The safety management of the emergency exit, by directly related to the $civil^{\circ}$Øs dead in the fire situation, have limited by which the fire station take the on-side and control-centered way of business processing, it is expect to the effects in which the citizen have to concern and to take part. From 2010 years in the back-ground, it is operated nationally the report and reward system on an illegal behavior of the emergency exit, it is happened to the unfit operating situation in the mission and direction of the system up which the exit paparazzi act with intent to receive the reward payments. The study suggests solution through analyzing the illegal emergency exit operation result of sixteen counties and the Seoul metropolitan from year 2010 to 2011. Firstly, the report destination is adjusted to the multiple use establishments and the large-scale multiple use facilities over the limit level is limited under five times the report events of the same people in the minor endorsement. And the fine incomes should be invested to the disaster prevention acting related with the exit. Secondly, for upgrade of the report accuracy, a reporter is received the possible information for the confirmation of an illegal act, has become to lead the pre-monitoring act which the reporter is can to take the safety education and to guide the information about season and vulnerable business location. Finally, considering the support way about the encounter facility, the fire officer is not happen to occur the repetitive report in the same place, is related to the volunteer service system the report acts, consider as the volunteer service time, and must support them to act as the disaster prevention volunteer.

The Analysis of Effect of Biopolymer Treated Soils in Seed Spray Method in the River Embankment (제방 녹화공법에서 바이오폴리머 처리토의 효능 분석)

  • Seo, Seunghwan;Jin, Seungnam;Chang, Ilhan;Chung, Moonkyung
    • Ecology and Resilient Infrastructure
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    • v.6 no.4
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    • pp.304-313
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    • 2019
  • Biopolymer based on microbial β-glucan and xanthan gum is effective for vegetation and has a function of enhancing soil strength, which can be used as soil reinforcement and stabilization materials in river embankment. The purpose of this study is to verify the vegetation effect of the surface of levee by biopolymer with seed spraying method. Mixed soils with biopolymer were used to cover the surface of embankments. The strength is higher in biopolymer-treated soil and xanthan gum based biopolymer has advantage for quality control in field scale. In addition, the vegetation of F. arundinacea and L. perenne showed various reactions with types of biopolymers. Biopolymer has a positive effect on the vegetation of them. In contrast, root growth tended to decrease in biopolymer-treated soils. The results indicate that root growth is slow down due to increasing ability to retain water in biopolymer-treated soil. In order to apply biopolymer to river embankment, it is necessary to examine the effects of biopolymers on a wide range of plant species in river embankment.

Emotion Changes during Virtual Bowling Game: An EEG Study on Hemispheric Asymmetry (가상현실볼링 수행에 따른 정서변화: 대뇌반구 비대칭 연구)

  • Shin, Kyeong-Sik;Kim, Jin-Gu;Ryu, Kwang-Min
    • Science of Emotion and Sensibility
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    • v.20 no.1
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    • pp.49-56
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    • 2017
  • The purpose of this study was to investigate the effects of virtual reality bowling on emotional changes using EEG (Electroencephalogram). Sixteen bowling players who have at least three years of experiences in bowling participated in this study. Their aged ranged from 26 to 35 years old with a mean age of 29.6 years. The frontal lobes (Fp2-Fp1, F4-F3, F8-F7) of each player were measured while subjects were performing five games of bowling. And after performing every frame, their emotion was measured immediately with Visual Analogue Scale. The data were analyzed by one-way analysis of variance to test differences in the alpha value of each region of the frontal lobes. The dependent variable is the alpha power of the cerebral asymmetry. The results showed that players who scored a strike showed higher VAS values than those who missed the spares or cleared the spares; those who cleared spares showed higher VAS values than those who missed spares In addition, with respect to frontal R-L asymmetry score, the alpha-wave of the left frontal lobe was activated when scoring a strike and clearing spares and the alpha-wave of the right frontal lobe was activated when missing spares. In conclusion, the results of this study demonstrated that success or achievement in competition gives rise to positive emotions and vice versa. This study neurophysiologically proved that performance outcomes during a competition directly influence players' emotion and brain waves.

Verification of Stream Flow by Rainfall-Runoff Simulation and Hydrologic Analysis in Daecheong Basin (수문 특성 분석에 의한 대청유역 주요지점 유출모의 검증)

  • Lee, Sang-Jin;Kim, Joo-Cheol;Noh, Joon-Woo
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.183-189
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    • 2010
  • In this study long term rainfall-runoff model, developed based on SSARR, was applied to Geum river basin and its simulation results of major control points were compared with the corresponding observed channel discharges. The validities of the simulation results were examined with re-measured discharges of those control points. From the above procedure the points showing the unreliable results were found out and its principal causes are analyzed through hydrological inspection of runoff characteristics of their circumstances. Finally the simulation results were modified by the consideration of the effects by small-scale hydraulic structures which could directly affect the channel discharges. As a result the annual runoff simulations of two major points in Geum river basin, Yongdam and Daecheong dam sites, work well. However the low flow simulation of the point located between them, Sutong station, showed more or less the unreliable result. Its causes are considered by means of the hydraulic/hydrological inspection of the corresponding point.