• Journal of the Korean Society of Earth Science Education
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• v.15 no.3
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• pp.335-344
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• 2022

This study was conducted for 4 weeks on the preparation of the science teaching/learning course plan for 109 students in 4 classes of the 2nd year intensive course at B University of Education. Pre-service elementary teachers attended a two-week field training practice after listening to a lecture on how to write a science teaching and learning course plan. Pre-service elementary teachers tried to find out about the selection of materials and the degree of connection between the course plan and the class to prepare the science teaching/learning course plan. The researcher completed the questionnaire by reviewing and deliberation on the questionnaire questions together with 4 pre-service elementary teachers. The questionnaire related to the writing of the science teaching and learning course plan consists of 8 questions. Preferred reference materials when writing the course plan, the level of interest in learning, the success or failure of the science course plan and class, the science preferred model, the evaluation method in unit time, and the science teaching and learning One's own efforts to write the course plan, the contents of this course are the science faculty. It is composed of the preparation of the learning process plan and how helpful it is to the class. The results of this study are as follows. First, it was found that elementary school pre-service elementary teachers preferred teacher guidance the most when drafting science teaching and learning curriculum plans. Second, it is recognized that the development stage is very important in the teaching and learning stage of the science department. Third, Pre-service elementary teachers believe that the science and teaching and learning process plan has a high correlation with the success of the class. Fourth, it was said that the student's level, the teacher's ability, and the appropriate lesson plan had the most influence on the class. Fifth, it was found that pre-service elementary teachers prefer the inquiry learning class model. Sixth, it was found that reports and activity papers were preferred for evaluation in 40-minute classes. Seventh, it was stated that the teaching and learning process plan is highly related to the class, so it will be studied and studied diligently. Eighth, the method of writing a science teaching and learning course plan based on the instructional design principle is interpreted as very beneficial.

• Journal of the Korean Society of Earth Science Education
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• v.15 no.3
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• pp.354-372
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• 2022

The purpose of this study is to explore the philosophical position of various scientific theories based on the scientific worldviews for science education. In addition, it aims to expand science education, which has usually dealt with epistemology and methodology, to ontology, that is, to the problem of metaphysics. It can be said that there exists a physical realism, traditionally defined as a strong determinism of the metaphysical belief. That is fixed and unchanging objective scientific knowledge independent of our minds, which was established by Newton, Einstein and Schridinger. What can be seen in the natural laws of dynamics can be called 'mathematicization'. Einstein also shook the traditional views to some extent through the theory of relativity, but his theory was still close to traditional thinking. On the contrary, to escape from this rigid determinism, we need anthropomorphic concepts such as 'possibility' and 'chance'. It is a characteristic of the modern scientific worldviews that leads the change of scientific theory from a classically strong deterministic thought to a weak deterministic accidental accident, probability theory, and a naturalistic point of view. This can be said to correspond to Darwin's theory of evolution and quantum mechanics. We can have three types of epistemological worlds that justify this ontological worldviews. These are rationalism, empiricism and naturalism. In many cases, science education does not tell us what kind of metaphysical beliefs the scientific theories we deal with in the field of education are based on. Also, science education focuses only on the understanding of scientific knowledge. However, it can be said that true knowledge can bring understanding only when it is connected to the knowledge of learned knowledge and the learner's own metaphysical belief in the world. Therefore, in the future, science education needs to connect various scientific theories based on scientific worldviews and philosophical position and present them to students.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.285-294
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• 2022

In order to accurately calculate greenhouse gas emissions in the agricultural field, Korea has been developing national-specific emission factors through direct measurement of gas fluxes using the closed-chamber method. In the rice paddy, only national-specific emission factors for methane (CH₄) have been developed. It is thus necessary to develop those for nitrous oxide (N₂O) affected by the application of nitrogen fertilizer. However, since the concentration of N₂O emission from rice cultivation is very low, the QA/QC methods such as method detection and practical quantification limits are important. In this study, N₂O emission from a rice paddy was evaluated affected by the amount of nitrogen fertilizer, by taking into account both method detection and practical quantification limits for N₂O concentration. The N₂O emission from a rice paddy soils affected by the nitrogen fertilizer application was estimated in the following order. The method detection limit (MDL) of N₂O concentration was calculated at 95% confidence level based on the pooled standard deviation of concentration data sets using a standard gas with 98 nmol mol^-1 N₂O 10 times for 3 days. The practical quantification limit (PQL) of the N₂O concentration is estimated by multiplying 10 to the pooled standard deviation. For the N₂O flux data measured during the rice cultivation period in 2021, the MDL and PQL of N₂O concentration were 18 nmol mol^-1 and 87 nmol mol^-1, respectively. The measured values above the PQL were merely about 12% of the total data. The cumulative N₂O emission estimated based on the MDL and PQL was higher than the cumulative emission without nitrogen fertilizer application. This research would contribute to improving the reliability in quantification of the N₂O flux data for accurate estimates of greenhouse gas emissions and uncertainties.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.330-336
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• 2022

It is likely that the heading would occur early when air temperature increases. In 2022, however, the heading date was delayed unusually, e.g., by 3 to 5 days although temperature during the vegetative growth stage was higher than normal years. The objective of this study was to identify the cause of such event analyzing weather variables including average temperature, sunshine hours, and day-length for each growth stage. The observation data were collected for medium-late maturing varieties, which has been grown at crop yield experiment sites including Daegu, Andong, and Yesan. The difference in heading date was compared between growing seasons in 2021 and 2022 because crop management options, e.g., the cultivars and cultivation methods, were identical at those sites during the study period. It appeared that the heading date was delayed due to the difference in temperature responsiveness under a given day-length condition The effect of the temperature increase on the heading date differed between the periods during which when the day-length was more than 14.3 hours before and after the summer-solstice.. The effect of the temperature decrease during the period from which the day-length decreased to less than 14.3 hours to the heading date was relatively greater. This merits further studies to examine the response of rice to the temperature change under different day-length and sunshine duration in terms of heading.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.149-156
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• 2023

The purpose of this study is to compare of growth and chlorophyl between old-barley seed (OBS, 2019) and New-barley seed (NBS, 2020) exposed by X-ray. After germination the OBS and NBS, experimental group was exposed by 30 Gy X-ray using linear accelerator (Clinac IS, VERIAN, USA), by 6 MV X-ray, SSD 100 cm, 18 × 10 cm², 600 MU/min. Length was measured every day until 9th day, and chlorophyl was analyzed using spectrophotometer(uv-1800, shimadzu, japan) after measuring weight in 9th day. Data analysis was performed the Independent T-test using SPSS ver 26.0(Chicago, IL, USA). NBS grow more faster than OBS in control group, but OBS grow more faster than NBS in experimental group. Length of control group was longer significantly every day than that of experimental group in OBS. NBS weighted more than OBS in control group, but OBS weighted more than NBS in experimental group. In comparing chlorophyl density, NBS high more than OBS in control group as well as experimental group. Growth and weight of OBS was effected more those than NBS by X-ray, but NBS in chlorophyl by X-ray. It is expected to be used as basic data for future X-ray research in barley seed.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.4
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• pp.32-48
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• 2022

This study analyzed the construction pattern and historical reality of Gwallamji Pond(觀纜池) in the rear garden of Changdeokgung Palace(昌德宮), which has been received as distorted information and has not received sufficient attention. The main topics consisted of the construction period and reorganization in the pond garden, changes in the installed wooden bridge, the existence of the berthing facility, and whether the plan shape was deformed. The main results of this study can be summarized as follows. First, the Gwallamji Pond was already completed before the Gapsin Coup, which occurred in the year of King Gojong. Since then, the Gwallamji Pond area, including the surrounding facilities, has been neglected for a while and was extensively renovated in the early 1900s. It is difficult to find a clear basis for the suspension and resumption of the Gwallamji Pond construction proposed in the previous discussion. Second, three types of wooden bridges with different shapes and structures were installed sequentially in the Gwallamji Pond. In particular, the second wooden bridge, which installed after the maintenance of the Gwallamji Pond, is judged to be the pontoon bridge depicted in Donggweoldohyeong(東闕圖形), and the railing of the bridge was decorated to symbolize the imperial family of the Korean Empire. The third wooden bridge, which appeared intensively in Japanese colonial era, was a Japanese-style bridge. Third, a berth facility for boarding and disembarking existed on the eastern shore of the Gwallamji Pond. The berth facility is also described in Donggweoldohyeong and it remained until the Japanese colonial period. However, as the maintenance work of the Gwallamji Pond was carried out several times after liberation, the berth facility was gradually damaged, and there are no traces left now. Fourth, The Gwallamji Pond was originally constructed in a planar shape of the Korean Peninsula similar to the present. It is necessary to reconsider the conventional theory that the Gwallamji Pond, made in the shape of a gored-shaped bottle, was renovated in the shape of the Korean Peninsula in Japanese colonial era. Even when the term Pandoji Pond(半島池) first appeared, there was no view that the Japanese intentionally modified the Gwallamji Pond.

• Journal of Korean Elementary Science Education
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• v.41 no.4
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• pp.701-724
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• 2022

In this study, the Nature of Science (NOS) instrument for elementary school students in the form of open questionnaires was developed specifically to reveal elementary school students' perceptions of the NOS, and its validity and effectiveness were investigated. To develop a NOS instrument for elementary school students, problems that may occur when applying the existing NOS instruments to elementary school students were analyzed and based on this, the development direction of the NOS instrument was established. In addition, after selecting seven NOS types suitable for the level of elementary school students, the preliminary instrument was produced by modifying and supplementing the items in the existing instruments for each type or by developing new items. Finally, the NOS instrument consisting of eight questions was developed by adding one question asking for a comprehensive understanding of science to seven questions related to each type of NOS after a content validity test of the science education expert group. To verify the practical effect of the developed instrument, pre- and post-tests were conducted on 50 students in two classes of sixth grade at two elementary schools in Seoul: 'existing instrument → development instrument' in one class, and 'development instrument → existing instrument' in the other class. The collected data were then compared and evaluated through summary content analysis and analyzed by executing the Wilcoxon signed-rank test. As a result of comparing and analyzing students' responses to the existing NOS instrument and the developed NOS instrument, students' perspectives on the NOS were more diverse when using the developed instrument, and the level of error in the response caused by misinterpreting the intention of the question was reduced. In addition, when using the developed instrument, the responses of the majority of students at a statistically significant level changed more specifically. In this study, the implications for the development of NOS instruments suitable for elementary school students were discussed based on these results.

• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.4
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• pp.379-391
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• 2022

The current study aimed to compare the pH, solubility value, and ion release capability of premixed mineral trioxide aggregates (MTAs) versus conventional pulp capping materials before and after setting. The following materials were used: resin-modified calcium silicate cement (TheraCal LC^®, TLC), resin-modified calcium hydroxide cement (Ultra-Blend^TM plus, UBP), and 2 kinds of premixed MTA (Endocem MTA^® premixed regular [EMPR] and Well-Root^TM PT [WRP]). The specimens of each material were prepared before and after setting and were immersed in distilled water. The materials' pH and solubility value were assessed. Next, three kinds of ion (calcium, sulfide, and strontium) released by pulp capping materials were evaluated via inductively coupled plasma atomic emission spectrometry. In the after-setting group, the pH of TLC and UBP decreased. However, the pH of the premixed MTAs increased with time. TLC released a higher concentration of strontium ion compared with the other materials. Meanwhile, EMPR released a significantly high concentration of sulfide ion (p < 0.05). In the after-setting group, the 2 kinds of premixed MTAs released a significantly higher concentration of calcium ion compared with the other materials (p < 0.05). In the after-setting group, EMPR had a significantly low solubility value (p < 0.05). The Kruskal-Wallis test, followed by the Mann-Whitney U test with Bonferroni correction, was used in statistical analysis. In conclusion, resin-modified calcium silicate cement, modified calcium hydroxide cement, and the 2 kinds of premixed MTAs had an alkaline pH and low solubility value and they released various concentrations of ions after setting.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.548-556
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• 2022

In this study, basic data were obtained to determine the optimal cultivation method to achieve stable fruiting and yield increase in "Cheonhwang" jujube trees. Accordingly, thefructification, fruit characteristics, and yield according to tree age were analyzed. The mean (and range of) tree height, crown area, stem diameter near the root, clear stem length, number of main branches, and distance between main branches were 235.6 (217.4-253.8) cm, 3.5 (3.1-4.1) m², 5.5 (4.0-7.1) cm, 70.6 (66.2-72.7) cm, 9.7 (8.6-10.5), and 10.4 (7.9-14.2) cm, respectively. Correlationanalysis results indicated that tree age was positively correlated with crown area, stem diameter near the root, and clear stem length but not with the number of main branches. The mean number (and range) of fruit per fruit-bearing mother shoot and tree were 18.3 (16.7-18.3) and 170.7 (157.9-178.3), respectively. Tree age was not significantlycorrelated with fruiting characteristics (i.e., the numbers of fruit-bearing mother shoots per main branch, fruit-bearing shoots per fruit-bearing mother shoot, fruit per fruit-bearing shoot, and fruit per tree). Given that the shape of jujube trees is constantly managed according to the growing area and greenhouse type, the tree growth characteristics were more affected by tree management techniques than by tree age. The mean (and range of) fruit weight, fruit hardness, and soluble solid content were 28.6 (27.7-30.3) g, 29.4 (28.5-30.4) N, and 20.4 (19.3-21.0) °brix, respectively, and these fruit characteristics were not significantly correlated with tree age.The average yield per tree of the 'Cheonhwang' jujube cultivar was 4.9 (4.8-5.0) kg, which was not significantly correlated with tree age.

• Journal of Practical Agriculture & Fisheries Research
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• v.24 no.4
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• pp.11-17
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• 2022

Ginseng hydroponic cultivation was cultivated as a nutrient solution and the growth was investigated 60 days later. The length(cm) increased from EC1.0 and EC2.0 concentrations to 5.47cm before, followed by EC0.5, 2.5, 1.5, and 0.0. The weight(g) increased from EC1.0 concentration to 2.39g before, followed by EC1.5, 2.5, 0.5, 0.0 and 2.0. The width(mm) increased from EC1.0 concentration to 1.9mm than before, followed by EC2.5, 0.5, 1.5, 2.0, and 0.0. In the ginseng growth experiment according to nutritional components, the average length of NO₃-N mixed experiment increased to 0.33cm, the average weight of 0.04g, and the average width of 0.35mm. In the experiment in which NH₄-N was mixed without NO₃-N, the growth was reduced to 0.37cm in average length, 0.03g in average weight, and 0.22mm in average width. In an experiment in which germanium(Ge) is mixed with a nutrient component, the average length is increased to 0.33cm, the average weight is increased to 0.04g, and the average width is increased to 0.35mm, but in an experiment excluding germanium(Ge), the growth is reduced to 0.11cm, the average weight is 0.04g, and the average width is 0.03mm.