• Title/Summary/Keyword: science fair

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Cryptoporus volvatus (Peck) Shear: Mycelial characteristics under different culture conditions (한입버섯 균사체 특성과 배양 적정 조건)

  • Kyung-Hwa, Shin;Tae-Min, Park;Kyung-Gu, Min;Soon-Ja, Seok;Myung-Jun, Jang
    • Journal of Mushroom
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    • v.20 no.4
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    • pp.263-269
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    • 2022
  • This study investigated the culture characteristics of Cryptoporus volvatus, whichis grow naturally in Korea, to determine the suitable environmental conditions for its cultivation. The physiological characteristics of the mycelia were assessed according to the cultivation conditions, to determine the optimal conditions for artificial cultivation. The visual characteristics of the hyphae of Cryptoporus volvatus KACC52303 included an irregular and uneven surface and a fuzzy or cotton-like texture. Under the microscope, its microstructure showed pre-chlamydospore formation, but no clamps were seen. The appropriate culture temperature was found to be a medium/high temperature of approximately 25-30℃, and the optimal pH was found to have a wide range from weakly acidic (pH 4) to neutral (pH 7). In the optimal nutrient source experiment, hyphal growth was shown to be fair in a mixed medium with 2.5% dextrin as the carbon source and 0.1% yeast extract as the organic nitrogen source. Among the various amino acids, organic acids, and inorganic salts tested, the fastest hyphal growth was observed in the presence of leucine, acetic acid or gluconic acid, and KCl or KH2PO4, respectively. The column test showed that the best mycelial growth occurred in a mixed medium of 80% pine sawdust, 10% rice bran, and 10% corncob sawdust.

Keyword Analysis of Research on Consumption of Children and Adolescents Using Text Mining (텍스트마이닝을 활용한 아동, 청소년 대상 소비관련 연구 키워드 분석)

  • Jin, Hyun-Jeong
    • Journal of Korean Home Economics Education Association
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    • v.33 no.4
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    • pp.1-13
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    • 2021
  • The purpose of this study is to identify trends and potential themes of research on consumption of children and adolescents for 20 years by analyzing keywords. The keywords of 869 studies on consumption of children and adolescents published in journals listed in Korean Citation Index were analyzed using text mining techniques. The most frequent keywords were found in the order of youth, youth consumers, consumer education, conspicuous consumption, consumption behavior, and character. As a result of analyzing the frequency of keywords by dividing into five-year periods, it was confirmed that the frequency of consumer education was significantly higher betwn 2006 and 2010. Research on ethical consumption has been active since 2011, and research has been conducted on various topics instead of without a prominent keyword during the most recent 5-year period. Looking at the keywords based on the TF-IDF, the keywords related to the environment and the Internet were the main keywords between 2001 and 2005. From 2006 to 2010, the TF-IDF values of media use, advertisement education, and Internet items were high. From 2011 to 2015, fair trade, green growth, green consumption, North Korean defector youths, social media, and from 2016 to 2020, text mining, sustainable development education, maker education, and the 2015 revised curriculum appeared as important themes. As a result of topic modeling, eight topics were derived: consumer education, mass media/peer culture, rational consumption, Hallyu/cultural industry, consumer competency, economic education, teaching and learning method, and eco-friendly/ethical consumption. As a result of network analysis, it was found that conspicuous consumption and consumer education are important topics in consumption research of children and adolescents.

The Antecedents of Consumer's Perceived Value and Repurchase Intention in the O2O Food Delivery Service Value Chain (O2O 음식배달서비스에서 있어서의 소비자의 지각된 가치와 재구매 의도에 대한 선행요인 연구)

  • Wenzhou Zheng;Anurag Agarwal;Kwangtae Park
    • Journal of Service Research and Studies
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    • v.13 no.2
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    • pp.1-23
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    • 2023
  • In this study, we try to discover some success factors, for the entire value chain of the O2O food delivery industry in China, from ordering to delivery. We study the influence of three aspects of the value chain, namely, (1) the mobile platform, (2) the restaurant and food and (3) the delivery service, on the perceived value and repurchase intention of customers. Using structural equation modeling, we develop a structural research model with seven sets of hypotheses relating various independent variable constructs (platform, restaurant, and delivery) and dependent constructs (perceived value and repurchase intention). We find that usefulness of mobile app, the food condition and the availability of offline restaurants were significant antecedents for perceived value and repurchase intention. In addition, fair pricing was a significant antecedent for repurchase intention.

Media exposure analysis of official sponsors and general companies of mega sport event (메가 스포츠이벤트의 공식스폰서와 일반기업의 미디어 노출 분석)

  • Kim, Joo-Hak;Cho, Sun-Mi
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.8 no.4
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    • pp.171-181
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    • 2018
  • As the proportion of sports events in the sports industry grows, the official sponsor market for sports events is also increasing. But because official sponsors are limited and expensive, some companies approach sporting events by way of Ambush marketing. This study is to analyze the differences of media exposure between official sponsors and general companies of mega sport events. To accomplish the purpose of the study, we collected text articles and analyzed them from the period of 2016 Rio Olympics, one year before the Olympics and one year after the Olympics. Web crawling was performed using Python for the collection of articles. Morphological and frequency analysis was performed using the KoNLP package and the TM package of statistical program R. In addition, the opinions of the related experts group were gathered to classify the companies or organizations in the media as the Organizing Committees for the Olympic Games(OCOGs), official sponsor, and general companies. As a result of the analysis, 5,220 times appeared related to the OCOGs, 7,845 times appeared related to the official sponsor, and 7,028 times appeared related to general companies. There isn't much difference in the frequency of exposure between official sponsors and general companies. It implies that Ambush marketing is recognized as a strategic marketing technique. The International Olympic Committee(IOC) has to recognize these social phenomena and establish reasonable standards for the marketing activities of official sponsors and general companies. And this study will serve as a basis for fair sponsor activities or marketing activities of sports events.

A Servicism Model for A New Democracy (서비스주의 민주주의 모델 연구)

  • Hyunsoo Kim
    • Journal of Service Research and Studies
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    • v.12 no.1
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    • pp.1-24
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    • 2022
  • This study was conducted to derive a new model for popular democracy in the modern society. The problem is exacerbated as the original model of democracy, isonomia, has faded and modern democracy is operated as a democracy in which the masses rule. Democracy is exposing a bigger problem due to the economic inequality caused by the majority rule and the capitalist economic system. Popular democracy, in which all the masses are equally qualified as sovereigns, is a structure in which cunning politicians can easily seize power if the voters are not wise. Isonomia is a system in which free people who solve economic problems on their own and have honesty, courage, dedication, sacrifice and sincerity set laws with the same qualifications, and keep the laws themselves, is a system that depends heavily on the conscience and virtue of free people. Modern popular democracy embodies the absolute equality of the sovereign regardless of economic power, but without the spirit of sacrifice and dedication to the community, those who can win popularity by wrapping themselves up as if they are sacrificial and capable people may seize power. This study presents a service-oriented democracy as a system that can maintain the merits of modern popular democracy while embodying the essence of isonomia. The system was implemented focusing on the qualifications for virtue, such as honesty, courage, sacrifice, integrity, etc., fair to all regardless of wealth. Human imperfections have been supplemented by the use of artificial intelligence. The assumption about the nature of the sovereign and public officials' agents was newly established, and the winner-take-allism problem was solved. This study proved that both the philosophy of Isonomia and the merits of Democracy can be realized through service-oriented democracy based on the common principle of humanity and the philosophy of service. Service-oriented democracy can be called revision democracy.

A Comprehensive Computer Program for Monitor Unit Calculation and Beam Data Management: Independent Verification of Radiation Treatment Planning Systems (방사선치료계획시스템의 독립적 검증을 위한 선량 계산 및 빔데이터 관리 프로그램)

  • Kim, Hee-Jung;Park, Yang-Kyun;Park, Jong-Min;Choi, Chang-Heon;Kim, Jung-In;Lee, Sang-Won;Oh, Heon-Jin;Lim, Chun-Il;Kim, Il-Han;Ye, Sung-Joon
    • Progress in Medical Physics
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    • v.19 no.4
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    • pp.231-240
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    • 2008
  • We developed a user-friendly program to independently verify monitor units (MUs) calculated by radiation treatment planning systems (RTPS), as well as to manage beam database in clinic. The off-axis factor, beam hardening effect, inhomogeneity correction, and the different depth correction were incorporated into the program algorithm to improve the accuracy in calculated MUs. A beam database in the program was supposed to use measured data from routine quality assurance (QA) processes for timely update. To enhance user's convenience, a graphic user interface (GUI) was developed by using Visual Basic for Application. In order to evaluate the accuracy of the program for various treatment conditions, the MU comparisons were made for 213 cases of phantom and for 108 cases of 17 patients treated by 3D conformal radiation therapy. The MUs calculated by the program and calculated by the RTPS showed a fair agreement within ${\pm}3%$ for the phantom and ${\pm}5%$ for the patient, except for the cases of extreme inhomogeneity. By using Visual Basic for Application and Microsoft Excel worksheet interface, the program can automatically generate beam data book for clinical reference and the comparison template for the beam data management. The program developed in this study can be used to verify the accuracy of RTPS for various treatment conditions and thus can be used as a tool of routine RTPS QA, as well as independent MU checks. In addition, its beam database management interface can update beam data periodically and thus can be used to monitor multiple beam databases efficiently.

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Morphologic Response of Gravel Beach to Typhoon Invasion - A Case Study of Gamji Beach Taejongdae in Busan (태풍 내습 시 자갈 해빈의 지형반응 - 부산 태종대 감지 해빈의 사례)

  • Lee, Young Yun;Chang, Tae Soo
    • Journal of the Korean earth science society
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    • v.41 no.1
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    • pp.19-30
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    • 2020
  • To understand the impact of typhoons on Gamji gravel beach Taejongdae in Busan, we carried out beach profiling using a VRS-GPS system and a Drone photogrammetry for the typhoons 'Kong-rey' invaded in October 2018 and 'Danas' in July 2019. In addition, grain sizes are analyzed to investigate the overall distribution pattern of gravels on the beach, and the beach topography is surveyed periodically to confirm the recovery rate of the beach. Grain-size analysis reveals that mean gravel sizes, in general, become finer from -6.2Φ to -5.4Φ towards the east in the seashore line direction. Variation in mean sizes is obviously observed in the cross-shore direction. Gravels in the swash zone are relatively fine about -4.5Φ in size and equant in shape, whereas the coarse and oblate gravels ranged from -5Φ to -6Φ are found in the berm. Gamji gravel beach particularly has two lines of berms: a lower berm situated facing beach and an upper berm about 10 m landward. After the typhoon Kong-rey passed by, about 1.4 m of severe erosion in upper berm occurred, and the berm eventually disappeared. On the backshore of the upper berm about 50 cm of erosion took place so that the elevation became lower. However, tangible erosion was not observed in the lower berm. When typhoon Danas hit, rated as mild storm, both upper and lower berm were eroded out. However, about 50 cm of deposition occurred only in the backshore. Only three days later, the new lower berm was formed, meaning that sedimentation rate must be high. This result indicates that Gamji gravel beach is recovered very fast from erosion caused by the typhoons when it is under the fair-weather condition even though beach morphology changes dramatically in a short period of time. Gravel beach is estimated to be or evaluated very resilient to typhoon erosion.

Analysis of Methoxyfenozide and Bentazone in Plant with HPLC by pH-Adjusted Liquid-liquid Partition Cleanup (pH조절 분배추출에 의한 식물체 중 Methoxyfenozide와 Bentazone의 HPLC 분석)

  • Lo, Seog-Cho;Hwang, Cheol-Hwan;Yoo, Ki-Yong;Han, Seong-Soo
    • Korean Journal of Environmental Agriculture
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    • v.26 no.3
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    • pp.246-253
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    • 2007
  • This study was performed to enhance the cleanup efficiency of methoxyfenozide and bentazone by pH adjustment in the course of liquid-liquid partition and to develop an optimum analytical conditions using HPLC coupled with DAD for two matrices, brown rice and rice straw. Preparation procedure of brown rice sample was "extraction${\rightarrow}$coagulation${\rightarrow}$liquid-liquid partition$\rightarrow$-florisil C.C", and this procedure was samely applied to two compounds. In rice straw, preparation procedure of methoxyfenozide sample was "extraction$\rightarrow$-alkalization$\rightarrow$liquid-liquid extraction$\rightarrow$coagulation$\rightarrow$florisil C.C", and in the case of bentazone, "extraction$\rightarrow$alkalization$\rightarrow$liquid-liquid partition$\rightarrow$acidification$\rightarrow$liquid-liquid extraction$\rightarrow$florisil C.C". All these purified samples were redissolved in the mobile phases, acetonitile : 20 mM sodium acetate (75:25, v/v) for methoxyfenozide and acetonitrile : 75 mM sodium acetate, pH 6.0 (40:60, v/v) for bentazone. Recoveries of methoxyfenozide analysis in brown rice and rice straw were 83.5-97.4 and 86.4-97.3%, and detection limits were 0.02 and 0.04 mg/kg, respectively. Recoveries of bentazone in brown rice and rice straw were 86.8-101.9 and 88.3-94.5% and detection limits were 0.005 and 0.01 mg/kg, respectively. This methods seem to be usefully applied to the residue analysis of two compounds in the view of producing stable analytical condition and fair reproducibility.

Dynamic Contrast-Enhanced MR Imaging in Detecting Local Tumor Progression after HIFU Ablation of Localized Prostate Cancer (국소적 전립선암의 고강도 집속 초음파 치료 후 국소적 암 재발의 발견과 역동적 조영증강 자기공명영상의 역할)

  • Park, Jung Jae;Kim, Chan Kyo;Lee, Hyun Moo;Park, Byung Kwan;Park, Sung Yoon
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.3
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    • pp.192-199
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    • 2013
  • Purpose : To retrospectively evaluate the diagnostic performance of dynamic contrast-enhanced MR imaging (DCE-MRI) in detecting recurrent prostate cancer after HIFU of clinically localized cancer, as compared with T2-weighted imaging (T2WI). Materials and Methods: Twenty-six patients with increased prostate-specific antigen levels after HIFU were included in this study. All MR examinations were performed using T2WI and DCE-MRI, followed by transrectal ultrasound-guided biopsy. MRI and biopsy results were correlated in six prostate sectors. Residual or recurrent cancer after HIFU was defined as local tumor progression if biopsy results showed any cancer foci. Two independent readers interpreted the MR images. Results: Of 156 prostate sectors, 51 (33%) were positive for cancer in 17 patients. For detecting local tumor progression, the sensitivity of DCE-MRI and T2WI was 80% and 57% for reader 1 (P < 0.001) versus 84% and 61% for reader 2 (P < 0.001), respectively. The specificity and overall accuracy between DCE-MRI and T2WI showed no statistical difference in both readers (P > 0.05). Interobserver agreement of DCE-MRI and T2WI was moderate and fair, respectively. Conclusion: For detecting local tumor progression of prostate cancer after HIFU, DCE-MRI was more sensitive than T2WI, with less interobserver variability.

Characteristics of Pollution Loading from Kyongan Stream Watershed by BASINS/SWAT. (BASINS/SWAT 모델을 이용한 경안천 유역의 오염부하 배출 특성)

  • Jang, Jae-Ho;Yoon, Chun-Gyeong;Jung, Kwang-Wook;Lee, Sae-Bom
    • Korean Journal of Ecology and Environment
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    • v.42 no.2
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    • pp.200-211
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    • 2009
  • A mathematical modeling program called Soil and Water Assessment Tool (SWAT) developed by USDA was applied to Kyongan stream watershed. It was run under BASINS (Better Assessment Science for Integrating point and Non-point Sources) program, and the model was calibrated and validated using KTMDL monitoring data of 2004${\sim}$2008. The model efficiency of flow ranged from very good to fair in comparison between simulated and observed data and it was good in the water quality parameters like flow range. The model reliability and performance were within the expectation considering complexity of the watershed and pollutant sources. The results of pollutant loads estimation as yearly (2004${\sim}$2008), pollutant loadings from 2006 were higher than rest of year caused by high precipitation and flow. Average non-point source (NPS) pollution rates were 30.4%, 45.3%, 28.1% for SS, TN and TP respectably. The NPS pollutant loading for SS, TN and TP during the monsoon rainy season (June to September) was about 61.8${\sim}$88.7% of total NPS pollutant loading, and flow volume was also in a similar range. SS concentration depended on precipitation and pollution loading patterns, but TN and TP concentration was not necessarily high during the rainy season, and showed a decreasing trend with increasing water flow. SWAT based on BASINS was applied to the Kyongan stream watershed successfully without difficulty, and it was found that the model could be used conveniently to assess watershed characteristics and to estimate pollutant loading including point and non-point sources in watershed scale.