• Proceedings of the Korean Society of Crop Science Conference
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• 2020.06a
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• pp.37-37
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• 2020

• Korean Journal of Environmental Agriculture
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• v.16 no.2
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• pp.136-141
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• 1997

In this study, we can be obtained the following conclusions about the characteristics of leachate with passed time in the expired landfill. Compared with the expired landfilling H. and S., pH shows a tendency to increase in E., because $NH_3$ is created by anaerobic degradation and dissolved in leachate. The initial BOD and COD of E. and S. are high in similar concentration but H. is low, Since the organics of waste in H. are lower than in E. and S. during landfilling. SS of E. in concentration is increased and very altered, because food of combustible in E. is higher than it in H. and S.. According to passed time, T-N is high in concentration but T-P shows a similar tendency. Heavy metals of leachate is lower than threshold concentrations. If leachate is treated biologically, microbes are not inibitory.

• Journal of the Korean Society for information Management
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• v.34 no.2
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• pp.81-95
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• 2017

This study examined two characteristics of library and information science (LIS) journals in Korea through analysis of journal coupling with common authors. This study also illustrated the trend of Korean LIS research in the recent decade. The notable change is that record management and archival studies settle in LIS domain as a major research area. We introduced two indicators, Publishing Preference Index (PPI) and Researcher Attraction Index (RAI), based on the degree of common authors among journals. Both indicators revealed notable changes in author coupling, including reversal of PPIs in some journals, which can be interpreted as proof of changes in their author groups. The RAI analysis, which measured the degree of journals' attractiveness to Korean LIS researchers and author sharing between two journals, illustrated the journals' states in a domain; this result can help find both an isolated journal and strongly bonded journals in the specific domain. Journal coupling with common authors introduced in this study proved to be an effective investigative method for illustrating journals' states in a specified domain as well as a multidisciplinary area.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.1
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• pp.168-182
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• 2019

The objectives of this study were to examine the production processes and methods of "Forest Type Map Actualization Production (Database (DB) Construction Work Manual)" (Work Manual) identify issues associated with the production processes and methods, and suggest solutions for them by applying evaluation items to a 1:5k digital forest type map. The evaluation items applied to a forest type map were divided into zoning and attributes, and the issues associated with the production processes and methods of Work Manual were derived through analyzing the characteristics of the stand structure and fragmentation by administrative districts. Korea is divided into five divisions, where one is set as the area changed naturally and the other four areas set as the area changed artificially. The area changed naturally has been updated every five years, and those changed artificially have been updated annually. The fragmentation of South Korea was analyzed in order to examine the consistency of the DB established for each region. The results showed that, in South Korea, the number of patches increased and the mean patch size decreased. As a result, the degree of fragmentation and the complexity of shapes increased. The degree of fragmentation and the complexity of shapes decreased in four regions out of 17 regions (metropolitan cities and provinces). The results indicated that there were spatial variations. The "Forest Classification" defines the minimum area of a zoning as 0.1ha. This study examined the criteria for the minimum area of a zoning by estimating the divided object (polygon unit) in a forest type map. The results of this study revealed that approximately 26% of objects were smaller than the minimum area of a zoning. The results implied that it would be necessary to establish the definition and the regeneration interval of "Areas Changed Artificially and Areas Changed Naturally", and improve the standard for the minimum area of a zoning. Among the attributes of Work Manual, "Species Change" item classifies terrain features into 52 types, and 43 types of them belong to stocking land. This study examined distribution ratios by extracting species information from the forest type map. It was found that each of 23 species, approximately 53% of species, occupied less than 0.1% of Forested land. The top three species were pine and other species. Although undergrowth on unstocked forest land are classified in the terrain feature system, their definition and classification criteria are not established in the "Forest Classification" item. Therefore, it will be needed to reestablish the terrain feature system and set the definitions of undergrowth.

• Journal of The Korean Association For Science Education
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• v.38 no.6
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• pp.901-917
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• 2018

The purpose of this study is to develop the questionnaire on pre-service elementary teachers' recognition of self-understanding and change capacity for science education and to investigate their recognitions with it. At the beginning of the study, we made a tool to investigate the self-understanding and change capacity of pre-service elementary teachers through literature review and discussions. The former half of the questionnaire was related to self-understanding with factors such as 'self-concept clarity,' 'career identity' and 'self-efficacy:' 'self-understanding as a pre-service elementary teacher' (12 items) and 'self-understanding as a pre-service elementary science teacher' (12 items). Its latter half was about the change capacity with factors such as 'change sensitivity,' 'goal consciousness,' 'collaboration,' 'reflection,' and 'mastery.' It consisted of three parts: 'general change capacity,' 'change capacity as a pre-service elementary teacher' and 'change capacity as a pre-service elementary science teacher' with 17 items, respectively. With this tool, we surveyed 153 pre-service elementary teachers. The results are as follows: First, pre-service elementary teachers have a positive recognition about self-understanding and change capacity, but the recognition of self-understanding and change capacity as pre-service elementary science teachers were relatively less positive. Second, factors of self-understanding and change capacity as pre-service elementary science teachers have a significant correlation with each other. Especially, there was a high correlation between 'self-efficacy' of self-understanding and 'goal consciousness' and 'mastery' of change capacity. Based on these results, some implications for self-understanding and change capacity related to science education were discussed.

• Proceedings of the Korean Society for Information Management Conference
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• 2002.08a
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• pp.115-121
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• 2002

인터넷과 웹 기술의 발전은 전자도서관의 목록정보나 목차정보서비스에서 원문정보서비스로의 변화를 주도하고 있다. 그러나 대학에서 생산하는 학문적 가치가 높은 학술지들은 웹을 통해 원문으로 서비스되고 있지만 상이한 OPAC 시스템과 목록을 위한 통일된 메타데이터의 부재로 원문정보를 공유$.$활용하기가 매우 힘든 실정이다. 본 고에서는 각 대학에서 생산하고 구축된 원문정보를 메타데이터 기반의 목록시스템을 이용하여 모든 대학의 학술지 논문정보를 검색하여 공유할 수 있는 분담목록시스템모형을 제시함으로써 대학 학술지 이용의 효율적 방안을 모색 해보고자 한다.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.681-692
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• 2015

It is well documented that physiological and nutritional condition of wintering birds is strongly related to migration success to breeding sites, and also breeding success. However, how abiotic factors during winter affect the migration and breeding successes still remains unclear. Thus, this study developed a dynamic-state-dependent model for wintering life-history to identify the potential impact on the life-history, success to breeding site and breeding success of wintering birds, which are related to temperature fluctuation, interspecific competition and human disturbance at the wintering sites. To find the best-fit-model, we referred to the existing research data on wintering ecology of Red-crowned cranes (Grus japonensis) in Cheolwon, Korea, which is well documented as a long-term wintering study. Our model predicted that the higher temperature fluctuation and a higher rate of human disturbance are negatively related to migration success to breeding sites and their fitness, ultimately breeding success via changing of proportion in resource allocation (for e. g., lower energy compensation or higher level of stress accumulation). Particularly, the rate of body mass compensation after arrival at wintering sites may be accelerated when there are less temperature fluctuations and a lower rate of human disturbance. In addition, the rate of interspecific competition sharing the wintering foraging sites is negatively related to the rate of body mass compensation. Consequently, we discussed the conservation strategies of wintering birds based on the outcomes of the model.

• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.503-514
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• 2021

Rice production with adequate level of area is important for decision making of rice supply and demand policy. It is essential to grasp rice cultivation areas in advance for estimating rice production of the year. This study was carried out to classify paddy rice cultivation in Gimje-si using sentinel-1 SAR (synthetic aperture radar) and UAV imagery in early July. Time-series Sentinel-1A and 1B images acquired from early May to early July were processed to convert into sigma naught (dB) images using SNAP (SeNtinel application platform, Version 8.0) toolbox provided by European Space Agency. Farm map and parcel map, which are spatial data of vector polygon, were used to stratify paddy field population for classifying rice paddy cultivation. To distinguish paddy rice from other crops grown in the paddy fields, we used the decision tree method using threshold levels and random forest model. Random forest model, trained by mainly rice cultivation area and rice and soybean cultivation area in UAV image area, showed the best performance as overall accuracy 89.9%, Kappa coefficient 0.774. Through this, we were able to confirm the possibility of early estimation of rice cultivation area in Gimje-si using UAV image.

• Research in Plant Disease
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• v.30 no.2
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• pp.165-175
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• 2024

The Korean fir tree (Abies koreana), an endemic species of South Korea, is experiencing a severe decline in population due to climate change. Studies on the conservation of Korean fir have been extensive, yet research regarding its correlation with rhizosphere bacterial communities remains scarce, warranting further investigation. In this study, metagenome amplicon sequencing targeting the 16S rRNA V4 region was conducted to examine the presence of specific bacterial communities in Korean fir and to investigate potential differences based on habitat types (rhizosphere of native or cultivated trees, soil of dead trees, and bulk soil) and seasonal variations (April, June, September, November). Here we show that although we could not identify specific taxa highly specifically with Korean fir, the rhizosphere bacterial community in native trees exhibited less variability in response to seasonal changes compared to that in bulk soils. Suggesting the establishment of relatively stable bacterial populations around the Korean fir natural habitat. Further research on other types of rhizosphere and/or microbes is necessary to investigate the distinct relationship of Korean fir with microbial communities.

• Journal of Astronomy and Space Sciences
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• v.24 no.2
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• pp.125-134
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• 2007

In this paper, we analyze the orbital variation of the Korea Multi-Purpose SATellite-1(KOMPSAT-1) in a strong space environment due to satellite drag by solar and geomagnetic activities. The satellite drag usually occurs slowly, but becomes serious satellite drag when the space environment suddenly changes via strong solar activity like a big flare eruption or coronal mass ejections(CMEs). Especially, KOMPSAT-1 as a low earth orbit satellite has a distinct increase of the drag acceleration by the variations of atmospheric friction. We consider factors of solar activity to have serious effects on the satellite drag from two points of view. One is an effect of high energy radiation when the flare occurs in the Sun. This radiation heats and expands the upper atmosphere of the Earth as the number of neutral particles is suddenly increased. The other is an effect of Joule and precipitating particle heating caused by current of plasma and precipitation of particles during geomagnetic storms by CMEs. It also affects the density of neutral particles by heating the upper atmo-sphere. We investigate the satellite drag acceleration associated with the two factors for five events selected based on solar and geomagnetic data from 2001 to 2002. The major results can be summarized as follows. First, the drag acceleration started to increase with solar EUV radiation with the best cross-correlation (r = 0.92) for 1 day delayed F10.7. Second, the drag acceleration and Dst index have similar patterns when the geomagnetic storm is dominant and the drag acceleration abruptly increases during the strong geomagnetic storm. Third, the background variation of the drag accelerations is governed by the solar radiation, while their short term (less than a day) variations is governed by geomagnetic storms.