• Title/Summary/Keyword: seasonal change concept

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Hourly load forecasting (시간별 전력부하 예측)

  • Kim, Moon-Duk;Lee, Yoon-Sub
    • Proceedings of the KIEE Conference
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    • 1992.07a
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    • pp.495-497
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    • 1992
  • Hourly load forecasting has become indispensable for practical simulation of electric power system as the system become larger and more complicated. To forecast the future hourly load the cyclic behavior of electric load which follows seasonal weather, day or week and office hours is to be analyzed so that the trend of the recent behavioral change can be extrapolated for the short term. For the long term, on the other hand, the changes in the infra-structure of each electricity consumer groups should be assessed. In this paper the concept and process of hourly load forecasting for hourly load is introduced.

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An Analysis of the Effect of Climate Change on Nakdong River Environmental Flow (낙동강 유역 환경유량에 대한 기후변화의 영향 분석)

  • Lee, A Yeon;Kim, Sangdan
    • Journal of Korean Society on Water Environment
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    • v.27 no.3
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    • pp.273-285
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    • 2011
  • This study describes the modeling of climate change impact on runoff across southeast Korea using a conceptual rainfall-runoff model TANK and assesses the results using the concept of environmental flows developed by International Water Management Institute. The future climate time series is obtained by scaling the historical series, informed by 4 global climate models and 3 greenhouse gas emission scenarios, to reflect a $4.0^{\circ}C$ increase at most in average surface air temperature and 31.7% increase at most in annual precipitation, using the spatio-temporal changing factor method that considers changes in the future mean seasonal rainfall and potential evapotranspiration as well as in the daily rainfall distribution. Although the simulation results from different global circulation models and greenhouse emission scenarios indicate different responses in flows to the climate change, the majority of the modeling results show that there will be more runoff in southeast Korea in the future. However, there is substantial uncertainty, with the results ranging from a 5.82% decrease to a 48.15% increase in the mean annual runoff averaged across the study area according to the corresponding climate change scenarios. We then assess the hydrologic perturbations based on the comparison between present and future flow duration curves suggested by IMWI. As a result, the effect of hydrologic perturbation on aquatic ecosystems may be significant at several locations of the Nakdong river main stream in dry season.

Analysis of Changes in Elementary Students' Mental Models about the Causes of the Seasonal Change (계절 변화의 원인에 관한 초등학생의 멘탈 모델 변화 과정 분석)

  • Kim, Soon-Mi;Yang, Il-Ho;Lim, Sung-Man
    • Journal of The Korean Association For Science Education
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    • v.33 no.5
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    • pp.893-910
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    • 2013
  • The purpose of this study was to identify changes in mental models of students in the elementary school about causes of seasonal changes. During a total of eight sessions, eight sixth graders were asked to describe the causes of seasonal changes through pictures, writing and thinking aloud by using microgenetic research methods, and the changes in mental models were examined. When the research was conducted, linguistic and behavioral factors and contents of interviews of participants were recorded on video. Moreover, a variety of materials such as field observation chart were written by a researcher and mental models records were written by a student. The protocol was written by integration of collected results, and it was repeated to read and was inductively categorized. The results of this study were as follows: First, participants' mental models about causes of seasonal changes were changed in various paths within and across sessions. Participants' mental models that had been more changed in various ways were closer to the scientific model. In addition, like rotation and revolution, students who correctly established the preconceptions related to seasonal changes formed the mental models consistent with scientific concept based on new information. On the other hand, students who did not correctly establish the preconceptions did not deviate from non-scientific mental models. Second, prior knowledge, experience and information which participants held in advance, accuracy of prior knowledge, resolution of inconsistency between new knowledge and existing mental models, activation of mental models through operation of models and drawing an picture affected the changes of mental models. Teachers should provide to learners with sufficient experience which can be configured to various mental models in order to form the scientific concepts. And they need to let learners feel the doubt and resolve it through presentation of new teaching material which is inconsistent with the existing mental models.

Thre Traditional Perception and Viewpoint to Natural Environment in the Orient (동양의 전통적 환경인식과 환경관)

  • 오홍석
    • Hwankyungkyoyuk
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    • v.3 no.1
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    • pp.55-62
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    • 1992
  • In the orient, ancestor's perception to natural environment was related on the change of climate. Man had been a essence of the warm blood animal, which had suited in mild climate for living and acting. The weather of hot or cold was not only comfort in human life but influences negatively on human behavior. The most people of oriental was particularly interrelated to seasonal change of climate in earlier time. Because, there are elements such as temperature, humidity and wind in the category of climate, these elements differentiated seasonal change. The main methods of perception of natural environment were observed and classified. Although these methods were in the primitive stage, these coincided the tendency of modern science. For example, confucian was recognized the law of vertical air current that warm air rised and cold air sinked. And they could classify all elements nature based on the principles of 'Yin and Yang(陰陽論)' such as male and female, the sun and moon. shade and light etc. Thus results of the observation and the classification concerned with physical environment can be utilize a wisdom for progressive life of inhabitants. It was a origin of the education in natural environment. Commonness in the viewpoint of environment in the orient if recognized the law of circulation. Buddhism, originated in india, realized that all of phenomena in the world was changed slowly through the principles of cycle(輪廻說) such as male and female, the sun and moon, shade and light etc. Thus results of the observation and the classification concerned with physical environment can be utilized a wisdom for progressive life of inhabitants. It was a origin of the education in natural environment. Commonness in the viewpoint of environment in the orient if recognized the law of circulation. Buddhism, originated in India, realized that all of phenomena in the world was changed slowly through the principles of cycle(輪廻說). For example, whole of land is shifted from young stage to old stage as the life cycle of humanbeing. The theory of karma effects(葉報設) is so signify with the good result that good one's action is reap a sweet fruit. The most environmental problem in today must realized as a consequence of men's act. Then Taoism emphasized the pure nature without the artificiality. Because complexual environment was composed of several elements, It was maintained through the artificiality. Because complexual environment was composed of several elements, It was maintained through the interaction of cause and effects. The solution of environmental problem is maintenanced the harmony between cause and effects by a philosophical concept.

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Hybrid Phenomena in Modern Sports-Inspired Fashion (현대 스포츠 인스파이어드 패션에 나타난 하이브리드)

  • Lee, Young-Min;Park, Jae-Ok
    • The Research Journal of the Costume Culture
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    • v.18 no.3
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    • pp.569-587
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    • 2010
  • In the field of fashion in this modern era, the tendency of diversification has created a variety of hybrid patterns and this tendency is being accelerated simultaneously by the hybrid trend. This research aims to analyze the aesthetic features of hybrid fashion in the modern "Sports Inspired Fashion(SIF)." We analyze fashion in the past 10 years from 2001 S/S to 2010 S/S. We focus on the four largest worldwide collections from New York, Paris, Milano, and London and concentrate on analyzing the contents from 38 volumes of Gap Press magazine. To accomplish our goal of study, we first define the concept of sports-inspired fashion and propose a framework of analysis to study hybrid patterns by reviewing the previous studies on hybrid patterns. Second, we analyze a wide range of sports-inspired fashion examples that have appeared in Gap Press magazines for the past 10 years(those which have been inspired by sports uniforms and training wears). Third, we analyze and classify the hybrid patterns of sports-inspired fashion. The results of our research are as follows. We have collected a total of 534 SIF works from the whole set of 61359 pictures and examined 23 sports fields. In terms of seasonal changes, the SIF works were found the most in the spring collections. Then, we have identified 25 hybrid patterns. The time hybrid pattern comprises more than half of the data(58.2%). The class-culture hybrid patterns comprise 18.8%, while the gender hybrid patterns comprise 18.2%. However, the intercultural hybrid patterns were rarely found, comprising merely 5% of the data. Our analysis confirms that sports and sports wear fashion are changing and developing in truly diverse ways in this modern era. This trend has continued to influence the high fashion in the modern age and is expected to exert a continuous impact on the change of fashion in the future.

Virechana karma (therapeutic purgation) in the restoration of gut microbiota concerning Amavata (RA): A scientific exposition

  • Godbole, Amrit;Sweta, Sweta;Abhinav, Abhinav;Singh, O.P.
    • CELLMED
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    • v.11 no.1
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    • pp.1.1-1.4
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    • 2021
  • Background: Amavata is a disease that occurs as a result of the error of metabolism. Poor dietary habits and faulty Dincharya (daily regimen) and ritucharya (seasonal regimen) leading to deranged metabolism and Agni (metabolic fire) which results in the formation of Ama(undigested product of metabolism). When Amaconceals with Vata(subtle energy associated with movement) and circulates in the body under the influence of Vyana Vayu (omnipresent air)it clogs the srotasas (microchannels) and initiates the inflammatory cascade. Amavata is commonly correlated with rheumatoid arthritis (RA) while other forms of auto-immune disorders can also be included in Amavata.Dysbiosis of the gut microbiota (GM) has been connected to the onset of diverse autoimmune diseases. In this study, it was hypothesized that Panchakarma (bio-purificatory methods) based intervention such as Virechana Karma (therapeutic purgation) may influence microbiota. Materials and Methods: Various Ayurvedic literature were reviewed for the etiopathogenesis of Amavata. Different databases were searched with research papers related to Gut Dysbiosis and autoimmunity and management of RA. A connecting link between Intestinal Dysbiosis with the autoimmune mechanisms was established and it was also found that the bowel cleansing introduced a change to the GM. Conclusion: It was concluded that Virechana karma is effective in gut flora Dysbiosis. This study aims to correlate the ancient Ayurvedic principles related to Agni Bala(metabolic energy) and biopurificatory treatment modalities like Virechana karma (therapeutic purgation)with the modern concept of gut microbiota and its role in the pathogenesis of various autoimmune disorders such as rheumatoid arthritis. The article creates an understanding about principles of Ayurveda and its rationality in today's scientific world and thereby opens newer vistas of research in therapeutics from Ayurveda, which may be helpful in the management of various immune-mediated Diseases through Ayurveda.

Relationship Analysis of Reference Evapotranspiration and Heating Load for Water-Energy-Food Nexus in Greenhouse (물-에너지-식량 넥서스 분석을 위한 시설재배지의 기준작물증발산량과 난방 에너지 부하 관계 분석)

  • Kim, Kwihoon;Yoon, Pureun;Lee, Yoonhee;Lee, Sang-Hyun;Hur, Seung-Oh;Choi, Jin-Yong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.61 no.4
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    • pp.23-32
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    • 2019
  • Increasing crop production with the same amount of resources is essential for enhancing the economy in agriculture. The first prerequisite is to understand relationships between the resources. The concept of WEF (Water-Energy-Food) nexus analysis was first introduced in 2011, which helps to interpret inter-linkages among the resources and stakeholders. The objective of this study was to analyze energy-water nexus in greenhouse cultivation by estimating reference evapotranspiration and heating load. For the estimation, this study used the physical model to simulate the inside temperature of the agricultural greenhouse using heating, solar radiation, ventilated and transferred heat losses as input variables. For estimating reference evapotranspiration and heating load, Penman-Monteith equation and seasonal heating load equation with HDH (Heating Degree-Hour) was applied. For calibration and validation of simulated inside temperature, used were hourly data observed from 2011 to 2012 in multi-span greenhouse. Results of the simulation were evaluated using $R^2$, MAE and RMSE, which showed 0.75, 2.22, 3.08 for calibration and 0.71, 2.39, 3.35 for validation respectively. When minimum setting temperature was $12^{\circ}C$ from 2013 to 2017, mean values of evapotranspiration and heating load were 687 mm/year and 2,147 GJ/year. For $18^{\circ}C$, Mean values of evapotranspiration and heating load were 707 mm/year and 5,616 GJ/year. From the estimation, the relationship between water and heat energy was estimated as 1.0~2.6 GJ/ton. Though additional calibrations with different types of greenhouses are necessary, the results of this study imply that they are applicable when evaluating resource relationship in the greenhouse cultivation complex.

Analysis of Misconceptions on Oceanic Front and Fishing Ground in Secondary-School Science and Earth Science Textbooks (중등학교 과학 및 지구과학 교과서 조경 수역 및 어장에 관한 오개념 분석)

  • Park, Kyung-Ae;Lee, Jae Yon;Kang, Chang-Keun;Kim, Chang-Sin
    • Journal of the Korean earth science society
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    • v.41 no.5
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    • pp.504-519
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    • 2020
  • Oceanic fronts, which are areas where sea water with different properties meet in the ocean, play an important role in controlling weather and climate change through air-sea interactions and marine dynamics such as heat and momentum exchange and processes by which properties of sea water are mixed. Such oceanic fronts have long been described in secondary school textbooks with the term 'Jokyung water zone (JWC hereafter) or oceanic front', meaning areas where the different currents met, and were related to fishing grounds in the East Sea. However, higher education materials and marine scientists have not used this term for the past few decades; therefore, the appropriateness of the term needs to be analyzed to remove any misconceptions presented. This study analyzed 11 secondary school textbooks (5 middle school textbooks and 6 high school textbooks) based on the revised 2015 curriculum. A survey of 30 secondary school science teachers was also conducted to analyze their awareness of the problems. An analysis of the textbook contents related to the JWC and fishing grounds found several errors and misconceptions that did not correspond with scientific facts. Although the textbooks mainly uses the concept of the JWC to represent the meeting of cold and warm currents, it would be reasonable to replace it with the more comprehensive term 'oceanic front', which would indicate an area where different properties of sea water-such as its temperature, salinity, density, and velocity-interact. In the textbooks, seasonal changes in the fishing grounds are linked to seasonal changes in the North Korean Cold Current (NKCC), which moves southwards in winter and northwards in summer; this is the complete opposite of previous scientific knowledge, which describes it strengthening in summer. Fishing grounds are not limited to narrow coastal zones; they are widespread throughout the East Sea. The results of the survey of teachers demonstrated that this misconception has persisted for decades. This study emphasized the importance of using scientific knowledge to correct misconceptions related to the JWC, fishing grounds, and the NKCC and addressed the importance of transferring procedures to the curriculum. It is expected that the conclusions of this study will have an important role on textbook revision and teacher education in the future.