• The Korean Journal of Ecology
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• v.28 no.6
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• pp.365-373
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• 2005

Understanding the relation of water environmental factors and vegetation is critical to restoration and management of wetlands. To reveal relationships between representative plant groups and water environments, we measured cover and abundance of plant species, water depth, temperature, pH, conductivity, dissolved oxygen, $NH_4$-N, $NO_3$-N, and $PO_4-P$ concentration in water in Wangsuk stream (WS) and Gwarim reservoir (GR). This study was conducted monthly from May to October, 2004. Six vegetation groups $(W1{\sim}W6)$ in WS and five vegetation groups $(G1{\sim}G5)$ in GR were identified using TWINSPAN. WS was characterized by Phragmites japonica, Digitaria sanguinalis, Phalaris arundinacea, Beckmannia xyzigachne and Persicara hydropiper, Persicaria thunbergii, Typha angustifolia. GR was characterized by T. angustifolia, Scirpus tabernaemontani, P. thunbergii, Humulus japonicus and Scirpus fluviatilis, Typha orientalis, Zizania latifolia. The vegetation in WS experienced greater seasonal changes than in GR. A correspondence analysis suggests that water depth was the major environmental factor influencing the distribution of most plants communities in both wetlands.

• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.100-101
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• 1992

• Journal of Korean Elementary Science Education
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• v.33 no.2
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• pp.401-414
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• 2014

The purpose of this study is to investigate the elementary preservice teachers' conceptions about 'plastics' focusing on non-polar property from a National University of Education. For the study, the views about plastics, relative shapes of a water droplet on plastic or glass material, and relative shapes of water surface in the plastic or glass measuring cylinder were surveyed from the preservice teachers. And the responses were analyzed based on the patterns. The results from the study are as follows: First, most preservice teachers were well aware of the plastic products which are used in daily life. Second, the responses concerning the reason why plastics can be used commonly were divided into 2 categories with 14 sub-level groups. However relatively few preservice teachers mentioned regarding 'chemical stability' and 'conductivity', which are associated with the plastics' non-polar property. Third, it was found that 50 participants (30.1%) had 'Scientific conception (Sc)', 38 (22.9%) had 'Partial-scientific conception (Ps)', 66 (39.8%) had 'Misconception (Mc)', and 12 (7.2%) had 'No conception (Nc)' on the subject of the relative shapes of a water droplet. Fourth, the distribution patterns and the ratio of the preservice teachers' conception on the survey question 3 concerning the relative shapes of water surface were quite similar to those of the survey question 2. So it was concluded that overall understanding level of the preservice teachers was pretty low on the subjects of the relative polarities of the plastic, glass, and water as well as their interactions. Fifth, the distribution percentile of 'Sc'/'Ps'/'Mc'/'Nc' was not related with the gender but highly correlated with preservice teachers' academic field and their science subjects taken in high school. Based on the results from the study, some educational guidelines were suggested.

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.628-637
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• 2012

In this research, the textbook contents related to the ionization degree of strong acid in water were analyzed from 1945 year syllabus to chemistry II textbook in 2009 revised curriculum. Fifty chemistry teachers' cognition related to the species of strong acid in water, and the relationship between the degree of ionization was surveyed by a questionnaire and interviews. As results, most of the teachers thought the species of strong acid in water based on the degree of ionization represented on the chemistry II textbooks. They didn't recognize the conflict of the degree of ionization and definition of strong acid on the textbooks, and then they awakened the conflict, they could not solve the problem.

• Hwankyungkyoyuk
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• v.19 no.2 s.30
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• pp.96-107
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• 2006

Inquiry has great value in environmental education(EE). Being able to see the world environmentally through 'inquiry-based environmental education' can be an important value and goal of EE. In this study, we intended to develop an EE program of measuring activity of dissolved oxygen(DO), based on the theory of 'inquiry-based EE'. Especially, we recognized the potential that DO meter can be used in 'inquiry-based EE', and we tried to develop a model of inquiry-based EE using DO meter. As a result of this research, we present specific models of inquiry-based EE about how to perform measuring activity of DO and how to use the DO meter in laboratories and streams from the perspective of inquiry of water environment. In the process of program development, we considered organization of the inquiry process, use of concept and knowledge, scientific inquiry and insightful inquiry, integration, sustain-ability, content components of 'Environmental Studies for EE', developmental level and in-forest of students. The developed EE model is a scientific inquiry model, pursuing 'explanation' based on data collection. Through this model, we tried to make students see water environment more deeply. The developed program can be applied to various water environments, like laboratories, streams, ponds, etc. It can be more effective inquiry activity if we perform measuring activities simultaneously with PH, electrical conductivity, and turbidity meters.

• Journal of Soil and Groundwater Environment
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• v.20 no.5
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• pp.34-40
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• 2015

It is reported that the intensity of rainfall will likely increase, on average, over the world on 2000. For water resources security, many studies for flow paths from rainfall or snowmelt to subsurface have been conducted. In Korea, few isotopic studies for characterizations of flow path have been undertaken. For a better understanding of how water derived from atmosphere moves to subsurface and from subsurface to stream, an analysis of precipitation and stream water using oxygen-18 and deuterium isotopes in a small watershed, Dorim-cheon, Seoul, was conducted with high resolution data. Variations of oxygen-18 in precipitation greater than 10‰ (δ¹⁸O_max = −1.21‰, δ¹⁸O_min = −11.23) were observed. Isotopic compositions of old water (groundwater) assumed as the stream water collected in advance were −8.98‰ and −61.85‰ for oxygen and hydrogen, respectively. Using a two-component mixing model, hydrograph separation of the stream water in Dorim-cheon was conducted based on weighted mean value of δ¹⁸O. As a result, except of instant dominance of rainfall, contribution of old water was dominant during the study period. On average, 71.3% of the old water and 28.7% of rainfall contributed to the stream water. The results show that even in the small watershed, which is covered with thin soil layer in granite mountain region, the stream water is considerably influenced by old water inflow rather than rainfall.

• Journal of Forest and Environmental Science
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• v.34 no.1
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• pp.61-65
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• 2018

To know if small changes in rearing water temperature and density affect the number of bacterial and fungal colonies in metamorphosed frogs, Dybowski's frog tadpoles were reared from Gosner 25-26 stages at either low ($1^{\circ}C$ low to ambient water temperature), ambient, or high ($1^{\circ}C$ high) water temperature (each 15 tadpoles in 20 L water) condition and at either low (10 tadpoles/20 L water), medium (20 tadpoles), or high (30 tadpoles) density condition. Immediately after metamorphosis, we sampled bacteria and fungi from skin, liver, and heart of six metamorphosed frogs, randomly selected for each treatment group. After separate incubation of bacteria and fungi on 3M Petrifilm plates, we counted the number of bacterial and fungal colonies appeared on the plates and compared the numbers among the temperature and density treatment groups. For temperature treatment, high-temperature group had fewer bacterial colonies, while low-temperature group had more fungal colonies than the other two groups. For density treatment, low-density group had fewer bacterial colonies than the other two groups, but the number of fungal colonies were not different among the groups. Our results suggest that small increased rearing water temperature and lowered rearing density could potentially reduce pathogens in farming frogs.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.799-801
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• 2005

• Proceedings of the Korea Water Resources Association Conference
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• 1997.11a
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• pp.11-28
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• 1997

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.1
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• pp.169-179
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• 2017

The purpose of this research is to identify the overall operation status of the marine program, which operates in the Department attempted, in various qualities and operational programs consisting of lecturers derives the problem, and to the policy proposal accordingly. In order to complete the purpose, to analyzed based on the status of marine programs of the Marine Training Center Chungcheong Cluster of three Education Offices from 2014 until the first half of 2016. In addition to direct visit the scene to confirm the status of the data collected through field surveys and interviews were officials confirm the validity of the data, and also to obtain additional study. In conclusion, First, Establish measures for the reduction of blind spots urgent law. Second, Appliances installed for program development and Instructors training.