• Title/Summary/Keyword: Science and Technology (S&T)

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Effects of Various Physical and Chemical Factors on the Death of Trouble Seaweed Ulva australis (구멍갈파래(Ulva australis) 해조류 사멸에 미치는 여러 물리화학적 요인들의 영향)

  • Kim, Jin-Seog;Kwak, Hwa Sook;Kim, Bo Gwan
    • Weed & Turfgrass Science
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    • v.6 no.3
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    • pp.222-234
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    • 2017
  • Green tides, which was mainly caused by Ulva spp., have been increasing in severity and frequency globally, and have negatively affected on marine ecosystems. This study was conducted to investigate effects of various physical and chemical factors on the death of Ulva australis (ULAUS) and to consider a practical measures useful for alleviating Ulva bloom. Soaking of ULAUS thalli in pure water for 8 hr didn't induce a death, but incubation in 1.0-1.5% salinity for 7 d inhibited sporulation by about 70%. Desiccation gave rise to a serious damage when more than 40-50% of initial fresh weight was lost. ULAUS growth was sensitive to temperature and seriously inhibited from more than $30^{\circ}C$. At $35^{\circ}C$, $40^{\circ}C$, $45^{\circ}C$ and $50^{\circ}C$, treatment time required for 90-95% death of ULAUS thalli was 1 d, 10 min, 30 sec, and 1 sec, repectively. ULAUS growth was seriously inhibited at lower than pH 6.0 and completely dead at pH 4.0. Several compounds for ULAUS control was selected and the chemcals causing a rapid death were oxidants such as hydrogen peroxide and sodium percarbonate. Taken together, our results suggest that low salinities, dryness, pH, high temp. and compounds could be selected for Ulva bloom control, and high temperature and compounds seems to be useful for a development of practical control methods.

Design of Cloud-Based Data Analysis System for Culture Medium Management in Smart Greenhouses (스마트온실 배양액 관리를 위한 클라우드 기반 데이터 분석시스템 설계)

  • Heo, Jeong-Wook;Park, Kyeong-Hun;Lee, Jae-Su;Hong, Seung-Gil;Lee, Gong-In;Baek, Jeong-Hyun
    • Korean Journal of Environmental Agriculture
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    • v.37 no.4
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    • pp.251-259
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    • 2018
  • BACKGROUND: Various culture media have been used for hydroponic cultures of horticultural plants under the smart greenhouses with natural and artificial light types. Management of the culture medium for the control of medium amounts and/or necessary components absorbed by plants during the cultivation period is performed with ICT (Information and Communication Technology) and/or IoT (Internet of Things) in a smart farm system. This study was conducted to develop the cloud-based data analysis system for effective management of culture medium applying to hydroponic culture and plant growth in smart greenhouses. METHODS AND RESULTS: Conventional inorganic Yamazaki and organic media derived from agricultural byproducts such as a immature fruit, leaf, or stem were used for hydroponic culture media. Component changes of the solutions according to the growth stage were monitored and plant growth was observed. Red and green lettuce seedlings (Lactuca sativa L.) which developed 2~3 true leaves were considered as plant materials. The seedlings were hydroponically grown in the smart greenhouse with fluorescent and light-emitting diodes (LEDs) lights of $150{\mu}mol/m^2/s$ light intensity for 35 days. Growth data of the seedlings were classified and stored to develop the relational database in the virtual machine which was generated from an open stack cloud system on the base of growth parameter. Relation of the plant growth and nutrient absorption pattern of 9 inorganic components inside the media during the cultivation period was investigated. The stored data associated with component changes and growth parameters were visualized on the web through the web framework and Node JS. CONCLUSION: Time-series changes of inorganic components in the culture media were observed. The increases of the unfolded leaves or fresh weight of the seedlings were mainly dependent on the macroelements such as a $NO_3-N$, and affected by the different inorganic and organic media. Though the data analysis system was developed, actual measurement data were offered by using the user smart device, and analysis and comparison of the data were visualized graphically in time series based on the cloud database. Agricultural management in data visualization and/or plant growth can be implemented by the data analysis system under whole agricultural sites regardless of various culture environmental changes.

Selection of Representative Foods and 'Best-fit' Mapping of Other Foods for Estimation of a Comprehensive Exposure to Food Contaminants in a Korean Total Diet Study (한국인의 유해물질 식이 노출량 평가를 위한 대표식품 선정과 mapping)

  • Koh, Eun-Mi;Shin, Hye-Hyung;Yon, Mi-Yong;Nam, Eun-Jeong;Lee, Yoon-Na;Kim, Do-Hee;Lee, Jee-Yeon;Kim, Mee-Hye;Park, Sung-Kug;Choi, Hoon;Kim, Cho-Il
    • Korean Journal of Food Science and Technology
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    • v.43 no.6
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    • pp.773-782
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    • 2011
  • A food list representing the typical diet of Koreans was developed for a total diet study based on the 687 food items which appeared in the dietary intake data collected during the 2008 & 2009 Korea National Health & Nutrition Examination Survey. Food items included in 90% of the cumulative intake, items with a consumption frequency of 5% or higher and items contributing to 80% of cumulative fat intake were considered first. From the resulting 165 food items, 15 items were removed to avoid similar foods, while 10 distinct items were added to increase the efficiency of 'best-fit' mapping. Consequently, 160 items were selected as representative foods, which cover 90.93% of intake amount, 91.36% of energy intake and 89.05% of fat intake. Given that every food consumed by Koreans can't be analyzed for contaminants of interest, mapping other foods to the previously mentioned representative 160 foods is warranted because it enables a more comprehensive dietary exposure assessment that is close to reality.

Establishment and application of a qualitative real-time polymerase chain reaction method for detecting genetically modified papaya line 55-1 in papaya products (RT-PCR을 이용한 유전자변형파파야(55-1)검사법 확립 및 파파야가공식품의 적용 연구)

  • Kwon, Yu Jihn;Chung, So Young;Cho, Kyung Chul;Park, ji Eun;Koo, Eun Joo;Seo, Dong Hyuk;Kim, Eugene;Whang, Jehyun;Park, Seong Soo;Choi, Sun Ok;Lim, Chul Joo
    • Analytical Science and Technology
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    • v.28 no.2
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    • pp.117-124
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    • 2015
  • Genetically modified (GM) papaya line 55-1, which is resistant to PRSV infection, has been marketed globally. Prompt and sensitive protocols for specific detections are essential for the traceability of this line. Here, an event- and construct-specific real-time polymerase chain reaction (RT-PCR) method was established to detect 55-1. Qualitative detection was possible for fresh papaya fruit up to dilutions of 0.005% and 0.01% for the homozygous SunUp and heterozygous Rainbow cultivars, respectively, in non-GM papaya. The method was applied in the qualitative detection of 55-1 in eight types of commercially processed papaya products. Additionally, papaya products were monitored to distinguish GM papaya using the P35S and T-nos RT-PCR detection methods. As expected, detection capacity was improved via modified sample preparation and the established RT-PCR detection method. Taking these results together, it can be suggested that a suitable method for the extraction and purification of DNA from processed papaya products was established for the detection of GM papaya.

Mitotic-Specific Methylation in the HeLa Cell through Loss of DNMTs and DMAP1 from Chromatin

  • Kim, Kee-Pyo;Kim, Gun-Do;Kang, Yong-Kook;Lee, Dong-Seok;Koo, Deog-Bon;Lee, Hoon-Taek;Chung, Kil-Saeng;Lee, Kyung-Kwang;Han, Yong-Mahn
    • Proceedings of the KSAR Conference
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    • 2003.06a
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    • pp.27-27
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    • 2003
  • A diversified and concentrative approach of methylation player can be one of the most powerful studies in the understanding of global epigenetic modifications. Previous studies have suggested that DNA methylation contributes to transcriptional silencing through the several DNA methylation-mediated repression systems by hypermethylation, including methyltransferases (DNMTs), DNA methyltransferase association protein 1 (DMAPl), methyl-CpG binding domain (MBD), and histone deacetylases (HDACs). Assembly of these regulatory protein complexes act sequentially, reciprocally, and interdependently on the newly composed DNA strand through S phase. Therefore, these protein complexes have a role in coupling DNA replication to the designed turn-off system in genome. In this study, we attempted to address the role of DNA methylation by the functional analysis of the methyltransferase molecule, we described the involvement of DMAP1 and DNMTs in cell divistion and the effect of their loss. We also described distinct patterns that DMAP1 and DNMTs are spatially reorganized and displaced from condensing chromosomes as cells progress through mitosis in HeLa cell, COS7, and HIH3T3 cell cycle progressions. DNMT1, DNMT3b, and DMAP1 do not stably contact the genetic material during chromosome compaction and repressive expression. These finding show that the loss of activities of DNMTs and DMAP1 occure stage specifically during the cell cycle, may contribute to the integral balance of global DNA methylation. This is consistent with previous studies resulted in decreased histone acetyltransferases and HDACs, and differs from studies resulted in increased histone methyltransferases. Our results suggest that DNA methylation by DNMTs and DMAP1 during mitosis acts to antagonize hypermethylation by which this mark is epigenetical mitotic-specific methylation.

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Interpreting Bounded Rationality in Business and Industrial Marketing Contexts: Executive Training Case Studies (집행관배훈안례연구(阐述工商业背景下的有限合理性):집행관배훈안례연구(执行官培训案例研究))

  • Woodside, Arch G.;Lai, Wen-Hsiang;Kim, Kyung-Hoon;Jung, Deuk-Keyo
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.3
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    • pp.49-61
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    • 2009
  • This article provides training exercises for executives into interpreting subroutine maps of executives' thinking in processing business and industrial marketing problems and opportunities. This study builds on premises that Schank proposes about learning and teaching including (1) learning occurs by experiencing and the best instruction offers learners opportunities to distill their knowledge and skills from interactive stories in the form of goal.based scenarios, team projects, and understanding stories from experts. Also, (2) telling does not lead to learning because learning requires action-training environments should emphasize active engagement with stories, cases, and projects. Each training case study includes executive exposure to decision system analysis (DSA). The training case requires the executive to write a "Briefing Report" of a DSA map. Instructions to the executive trainee in writing the briefing report include coverage in the briefing report of (1) details of the essence of the DSA map and (2) a statement of warnings and opportunities that the executive map reader interprets within the DSA map. The length maximum for a briefing report is 500 words-an arbitrary rule that works well in executive training programs. Following this introduction, section two of the article briefly summarizes relevant literature on how humans think within contexts in response to problems and opportunities. Section three illustrates the creation and interpreting of DSA maps using a training exercise in pricing a chemical product to different OEM (original equipment manufacturer) customers. Section four presents a training exercise in pricing decisions by a petroleum manufacturing firm. Section five presents a training exercise in marketing strategies by an office furniture distributer along with buying strategies by business customers. Each of the three training exercises is based on research into information processing and decision making of executives operating in marketing contexts. Section six concludes the article with suggestions for use of this training case and for developing additional training cases for honing executives' decision-making skills. Todd and Gigerenzer propose that humans use simple heuristics because they enable adaptive behavior by exploiting the structure of information in natural decision environments. "Simplicity is a virtue, rather than a curse". Bounded rationality theorists emphasize the centrality of Simon's proposition, "Human rational behavior is shaped by a scissors whose blades are the structure of the task environments and the computational capabilities of the actor". Gigerenzer's view is relevant to Simon's environmental blade and to the environmental structures in the three cases in this article, "The term environment, here, does not refer to a description of the total physical and biological environment, but only to that part important to an organism, given its needs and goals." The present article directs attention to research that combines reports on the structure of task environments with the use of adaptive toolbox heuristics of actors. The DSA mapping approach here concerns the match between strategy and an environment-the development and understanding of ecological rationality theory. Aspiration adaptation theory is central to this approach. Aspiration adaptation theory models decision making as a multi-goal problem without aggregation of the goals into a complete preference order over all decision alternatives. The three case studies in this article permit the learner to apply propositions in aspiration level rules in reaching a decision. Aspiration adaptation takes the form of a sequence of adjustment steps. An adjustment step shifts the current aspiration level to a neighboring point on an aspiration grid by a change in only one goal variable. An upward adjustment step is an increase and a downward adjustment step is a decrease of a goal variable. Creating and using aspiration adaptation levels is integral to bounded rationality theory. The present article increases understanding and expertise of both aspiration adaptation and bounded rationality theories by providing learner experiences and practice in using propositions in both theories. Practice in ranking CTSs and writing TOP gists from DSA maps serves to clarify and deepen Selten's view, "Clearly, aspiration adaptation must enter the picture as an integrated part of the search for a solution." The body of "direct research" by Mintzberg, Gladwin's ethnographic decision tree modeling, and Huff's work on mapping strategic thought are suggestions on where to look for research that considers both the structure of the environment and the computational capabilities of the actors making decisions in these environments. Such research on bounded rationality permits both further development of theory in how and why decisions are made in real life and the development of learning exercises in the use of heuristics occurring in natural environments. The exercises in the present article encourage learning skills and principles of using fast and frugal heuristics in contexts of their intended use. The exercises respond to Schank's wisdom, "In a deep sense, education isn't about knowledge or getting students to know what has happened. It is about getting them to feel what has happened. This is not easy to do. Education, as it is in schools today, is emotionless. This is a huge problem." The three cases and accompanying set of exercise questions adhere to Schank's view, "Processes are best taught by actually engaging in them, which can often mean, for mental processing, active discussion."

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The Prediction of Currency Crises through Artificial Neural Network (인공신경망을 이용한 경제 위기 예측)

  • Lee, Hyoung Yong;Park, Jung Min
    • Journal of Intelligence and Information Systems
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    • v.22 no.4
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    • pp.19-43
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    • 2016
  • This study examines the causes of the Asian exchange rate crisis and compares it to the European Monetary System crisis. In 1997, emerging countries in Asia experienced financial crises. Previously in 1992, currencies in the European Monetary System had undergone the same experience. This was followed by Mexico in 1994. The objective of this paper lies in the generation of useful insights from these crises. This research presents a comparison of South Korea, United Kingdom and Mexico, and then compares three different models for prediction. Previous studies of economic crisis focused largely on the manual construction of causal models using linear techniques. However, the weakness of such models stems from the prevalence of nonlinear factors in reality. This paper uses a structural equation model to analyze the causes, followed by a neural network model to circumvent the linear model's weaknesses. The models are examined in the context of predicting exchange rates In this paper, data were quarterly ones, and Consumer Price Index, Gross Domestic Product, Interest Rate, Stock Index, Current Account, Foreign Reserves were independent variables for the prediction. However, time periods of each country's data are different. Lisrel is an emerging method and as such requires a fresh approach to financial crisis prediction model design, along with the flexibility to accommodate unexpected change. This paper indicates the neural network model has the greater prediction performance in Korea, Mexico, and United Kingdom. However, in Korea, the multiple regression shows the better performance. In Mexico, the multiple regression is almost indifferent to the Lisrel. Although Lisrel doesn't show the significant performance, the refined model is expected to show the better result. The structural model in this paper should contain the psychological factor and other invisible areas in the future work. The reason of the low hit ratio is that the alternative model in this paper uses only the financial market data. Thus, we cannot consider the other important part. Korea's hit ratio is lower than that of United Kingdom. So, there must be the other construct that affects the financial market. So does Mexico. However, the United Kingdom's financial market is more influenced and explained by the financial factors than Korea and Mexico.

A study on ecotoxicity characteristics of public sewage treatment plant process using Daphnia magna (물벼룩을 이용한 공공하수처리시설 공정별 생태독성 특성 연구)

  • Gyeongrok Son;Haram Kim;Sungryong Park;Gwangwoon Cho;Yunhee Kim;Jintae Kim;Misook Goh;Kyoungran Moon;Gwangyeob Seo;Byunghoon Park
    • Journal of Korean Society of Water and Wastewater
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    • v.38 no.3
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    • pp.141-153
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    • 2024
  • The purpose of this study is to analyze the correlation between ecotoxicity and water quality items using Daphnia magna in public sewage treatment plant process and to obtain operational data to control ecotoxicity through research on removal efficiency. The average value of ecotoxicity was 1.39 TU in the influent, 1.50 TU in the grit chamber, and 0.84 TU in the primary settling tank and it was found that most organic matters, nitrogen, and phosphorus were removed through biological treatment in the bioreactor. Using Pearson's correlation analysis, the positive correlation was confirmed in the order of ecotoxicity and water quality items TOC, BOD, T-N, NH3-N, SS, EC, and Cu. As a result of conducting a multilinear regression analysis with items representing positive correlation as independent variables, the regression model was found to be statistically significant, and the explanatory power of the regression model was about 81.6%. TOC was found to have a significant effect on ecotoxicity with B=0.009 (p<.001) and Cu with B=16.670 (p<.001), and since the B sign is positive (+), an increase of 1 in TOC increases the value of ecotoxicity by 0.009 and an increase in Cu by 1 increases the value of ecotoxicity by 16.670. TOC (β=0.789, p<.001) and Cu (β=0.209, p<.001) were found to have a significant positive effect on ecotoxicity. TOC and Cu have a great effect on ecotoxicity in the sewage treatment plant process, and it is judged that TOC and Cu should be considered preferentially and controlled in order to efficiently control ecotoxicity.

Estimation of Genetic Parameters for Four Reproduction Component Traits in Two Chinese Indigenous Pig Breeds

  • Zhu, M.J.;Ding, J.T.;Liu, B.;Yu, M.;Fan, B.;Li, C.C.;Zhao, S.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.8
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    • pp.1109-1115
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    • 2008
  • The reproduction component traits are important components of sow efficiency. The objective of this study was to evaluate the phenotypic and genetic parameters of four reproduction component traits (age at puberty (AP), preweaning number dead (PND), weaning to service interval (WSI), and intra-individual SD in litter size (IISDLS)) of sows in two Chinese indigenous pig breeds. Available reproductive records including 22,591 piglets born from 2,054 litters by 574 Jiangquhai sows and 464 Meishan sows were used in this investigation. A set of mixed models and restricted maximum likelihood methodology were used for the multiple trait analyses of these traits. The results showed that the estimates of heritabilities (${\pm}$standard error) for AP, PND, WSI and IISDLS were $0.40{\pm}0.05$, $0.06{\pm}0.03$, $0.20{\pm}0.02$ and 0.09{\pm}0.03 in Jiangquhai sows, and $0.35{\pm}0.06$, $0.05{\pm}0.03$, $0.18{\pm}0.03$ and $0.10{\pm}0.04$ in Meishan sows, respectively. There was moderate genetic correlation between AP and WSI, while there were low genetic correlations between the other pairwise traits. The genetic correlations were positive for most of the pairwise traits, except for the one between AP and IISDLS. The results indicated that all traits except for AP were difficult to make genetic improvement by traditional selection methods due to low heritabilities and the favorable improvement of AP might result in unfavorable changes of IISDLS due to the trend of genetic antagonism.

Determination of Net Energy and Protein Requirements for Growth in Hanwoo Steers by Comparative Slaughter Experiment (비교도체법에 의한 한우 거세우의 증체에너지 및 단백질 요구량)

  • Kim, K.H.;Oh, Y.G.;Lee, S.C.;Shin, K.J.;Chung, W.T.;Kang, S.W.;Hong, S.K.;Ju, J.C.;Baek, B.H.
    • Journal of Animal Science and Technology
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    • v.49 no.1
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    • pp.41-50
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    • 2007
  • Data from a comparative slaughter experiment with two hundreds of Korean native (Hanwoo) beef steers were utilized to determine net energy and protein requirements for growth (NEg and NPg). Eight randomly selected steers were used in the initial slaughter group of 6 month of age and the remaining steers allocated to treatments within two groups. The restricted groups were fed 1.2 to 1.5% concentrate per kg body weight (BW) in the growing period (6~12 month of age), 1.7 to 1.8% concentrate per kg BW in the early fattening period (13~18 month of age), and concentrate feed ad libitum in the late fattening period (19~30 month of age). Ad libitum groups were fed concentrate ad libitum through the whole period. Rice straw was offered ad libitum for 24 month of two feeding systems. The steers were slaughtered when animals reached every 2 month from 8 to 30 month of age. For all body composition determinations, whole empty body components were weighed, taken each proportional subsample was ground for chemical analysis. Equations developed with the pooled data to predicted NEg and NPg were similar to the equations of Japanese Feeding Standard for Beef Cattle (2000). First equations were developed to predicted NEg; NEg = 0.05332×LBW0.75×DG for restricted treatment and NEg = 0.04912×LBW0.75×DG for ad libitum treatment. Second equations were developed to predicted NPg; NPg = DG × (224.7-0.251×LBW) for restricted treatment and NPg=DG×(210.1-0.214×LBW) for ad libitum treatment.