• Journal of Korean Elementary Science Education
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• v.41 no.4
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• pp.658-672
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• 2022

The unique teaching and learning difficulties of speed-related units in elementary school science are mainly due to the student's lack of mathematical thinking ability and procedural knowledge on speed measurement, and curriculums and textbooks must be constructed with these in mind. To identify the implications of composing a new science curriculum and relevant textbooks, this study reviewed the structure and contents of the speed-related units of three curriculums from the 2007 revised curriculum to the 2015 revised curriculum and the resulting textbooks and examined their relevance in light of the literature. Results showed that the current content carries the risk of making students calculate only the speed of an object through a mechanical algorithm by memorization rather than grasp the multifaceted relation between traveled distance, duration time, and speed. Findings also highlighted the need to reorganize the curriculum and textbooks to offer students the opportunity to learn the meaning of speed step-by-step by visualizing materials such as double number lines and dealing with simple numbers that are easy to calculate and understand intuitively. In addition, this paper discussed the urgency of improving inquiry performance such as process skills by observing and measuring an actual object's movement, displaying it as a graph, and interpreting it rather than conducting data interpretation through investigation. Lastly, although the current curriculum and textbooks emphasize the connection with daily life in their application aspects, they also deal with dynamics-related content somewhat differently from kinematics, which is the main learning content of the unit. Hence, it is necessary to reorganize the contents focusing on cases related to speed so that students can grasp the concept of speed and use it in their everyday lives. With regard to the new curriculum and textbooks, this study proposes that students be provided the opportunity to systematically and deeply study core topics rather than exclude content that is difficult to learn and challenging to teach so that students realize the value of science and enjoy learning it.

• Korean Association of Arts Management
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• no.58
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• pp.5-47
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• 2021

This paper is a story about five middle-aged men in their 50s who suddenly began their photographic activities as they reached middle age. In the perspective of Borudieu's cultural capital theory, this study observes five men in their 50s by implementing in-depth interviews about the motivation behind taking photographs, the experience of photography activities, and the rewards of these activities. The theory has undergone a theoretical revision with the criticism that factors other than the class can be influential. Based on these ideas, I have proceeded my study by preferentially grasping the notion of the 'field' in accordance with the specific history of Korean society. Therefore, this study sought to more specifically understand the various photographic activities of middle-class men in their 50s by referring Coskuner-Balli and Thompson's argument(2013), which revised 2018's cultural captial theory and proposed the concept of 'subordinate cultural capital' and 'leisure capital' who proposed by Backlund, E. A. & Kuentzel, W. F.(2013). As a middle-class men in their 50s, research participants have grown up and worked in a social atmosphere where economic capital is recognized as an individual's ability. However, they are faced with the value that the knowledge and taste towards culture and arts is one's identity. In addition to the subjective deprivation that arises from this situation, the lifespan characteristic of their age that it is on the brink of the old age appeared to have influenced them to put their psychological motivation immediately into practice. Economic capital was the main conversion terms to move form interest to practice, which includes 'time' as a resource as well as money. With the cultural practices being expanded since their creation of photographs, the reason that these expansions can be maintained more actively lies in their identity as 'cultural artist' that is consolidated in new relationships in the sharing of photographic activities. In this way, photographic activities grant a symbolic status of 'a middle-aged man who actively builds and expresses his identity' through the conversion of accumulating cultural capital and the conversion into social capital. Furthermore, the recognized scope of the symbolic capital acquired by the research participants is in the domain of the private life that is family and acquaintance. Especially, they were gaining a great psychological reward from their children's recognition that they are not just a 'breadwinner' but 'dad who cultivates himself with a culture and arts'. Accordingly, by considering that 'generation' other than class can be a meaningful discussion point when understanding Korea society from the perspective of cultural theory, this study is meaningful that a more flexible understanding of cultural theory can give a glimpse into the possibility of a more specific and diverse approach that will arise in the discussion of culture and arts education.

• Korean Journal of Heritage: History & Science
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• v.55 no.3
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• pp.46-58
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• 2022

This study analyzed the documentation trend of garden components such as plants, infrastructure, unit facilities, and structures, based on 188 measurement drawings of 94 old houses in a report on the documentation of the national folklore cultural heritage. The findings are as follows. First, it was found that plants and structures continuously appeared as the subject of measurement drawings, while infrastructure was often omitted. It was confirmed that unit facilities, which are smaller than other components, were frequently excluded from the documentation subject as well due to frequent changes such as movement, loss, and expansion. Second, the level of expression in measurement drawings showed different aspects for each component. The unit facilities showed a large change over time with respect to the level of documentation, and the level of documentation was somewhat polarized, particularly toward the latter stage. This suggests that the level of documenting the drawings limited to specific facilities improved, but the overall level of drawings did not improve, such as a lack of diversification of expression techniques suitable for various unit facilities. On the other hand, it was confirmed that the level of documenting the drawings for plants, infrastructure and structures did not change to a significant degree, implying that no improvements were made to the expression of components. Third, as for the technique of detailed expression, in the case of plants, vegetation status was prepared without distinction of old or protected trees that have historical value. Above all, there was no record of the vegetation structure that could help grasp the vegetation landscape of the outer area. As for the infrastructure, there was no consistent expression technique to systematically convey topographic changes such as the height and slope of the land. In addition, since there was no subtype classification defined for unit facilities and structures, there was no subject or method of documentation. This study is meaningful in that it expanded the category of documentation, which has been concentrated on buildings in old houses, to gardens, and called attention to the need for documenting the gardens for the preservation and management of old houses as an integration of the building and outer area.

• Journal of Life Science
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• v.32 no.12
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• pp.947-955
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• 2022

Silkworms, which have recently shown promise as functional health foods, show functional differences between varieties; therefore, the need for variety identification is emerging. In this study, we analyzed the whole silkworm genome to identify 10 unique silkworm varieties (Baekhwang, Baekok, Daebaek, Daebak, Daehwang, Goldensilk, Hansaeng, Joohwang, Kumkang, and Kumok) using single nucleotide polymorphisms (SNP) present in the genome as biomarkers. In addition, nine SNPs were selected to discriminate between varieties by selecting SNPs specific to each variety. We subsequently created a decision tree capable of cross-verifying each variety and classifying the varieties through sequential analysis. Restriction fragment length polymorphism (RFLP) was used for SNP867 and SNP9183 to differentiate between the varieties of Daehwang and Goldensilk and between Kumkang and Daebak, respectively. A tetra-primer amplification refractory (T-ARMS) mutation was used to analyze the remaining SNPs. As a result, we could isolate the same group or select an individual variety using the nine unique SNPs from SNP780 to SNP9183. Furthermore, nucleotide sequence analysis for the region confirmed that the alleles were identical. In conclusion, our results show that combining SNP analysis of the whole silkworm genome with the decision tree is of high value as a discriminative marker for classifying silkworm varieties.

• Ecology and Resilient Infrastructure
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• v.9 no.2
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• pp.113-123
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• 2022

The blood and physiological changes of common carp (Cyprinus carpio) and crucian carp (Carassius auratus) were analyzed when the water temperature was rapidly increased from 20℃ (control) to 26 and 32℃. The water temperature reached 26℃ and 32℃ within 6 hours from the water temperature of 20℃, and the control was maintained at 20℃ for the duration of the experiment. From each experimental group, blood was collected every 3, 12, 24 and 48 hours after the water temperature rise, and the red blood cell count, hemoglobin, hematocrit, Na⁺, K⁺, Cl^-, cortisol, glucose, aspartate amino transferase (AST) and alanine amino transferase (ALT) contents were analyzed. In the case of the crucian carp experimental group where the water temperature was raised to 32℃, the concentrations of plasma cortisol, glucose, AST and ALT increased 3 hours after the water temperature rise, and the concentrations did not decrease until 48 hours (P<0.05). Plasma cortisol, glucose, AST, and ALT in both C. carpio and C. auratus in the control group and the experimental group raised to 26℃ increased at 3 hours after the water temperature rise (P<0.05), and decreased to the value before the water temperature rise at 48 hours (P<0.05). The plasma Na⁺, K⁺ and Cl^- concentrations of C. carpio and C. auratus in the experimental group where the water temperature was raised to 32℃ were higher than in the 20 and 26℃ experimental groups. The blood reaction of all experimental groups including the control group showed a common trend in both C. carpio and C. auratus increasing up to 12 hours after the water temperature rise and then decreasing at 48 hours after the water temperature rise. The results derived from this study would be useful for investigating the physiological response of fish stress in future. In addition, as fish mortality has recently occurred frequently in rivers and lakes, it is judged that it can be used as basic data.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.3
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• pp.355-365
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• 2022

Precipitation and phase transition of iron minerals in mine drainage greatly affect the behavior of trace elements. However, the precipitation of ferrihydrite, one of the major iron minerals precipitated in drainage, and the related behavior of trace elements have hardly been studied. In this study, the effects of pH change and time on mineral precipitation characteristics in mine drainage from the Munkyeong coal mine were investigated, and the behavioral changes of trace elements related to the precipitation of these minerals were studied. In the case of precipitated mineral phases, goethite was observed at pH 4, and 2-line ferrihydrite mixed with small amount of 6-line ferrihydrite was mainly identified at pH 6 or higher. In addition, it was observed that the precipitation of calcite additionally increased as the pH increased in the samples at pH 6 or higher. The occurrence of goethite was probably due to the phase change of initially precipitated ferrihydrite within a short time under the influence of low pH. Our results showed that the concentration of trace elements was strongly influenced by pH and time. With increasing time, Fe concentration in the drainage showed a abrupt decrease due to the precipitation of iron minerals, and the concentration of As existing as oxyanions in the drainage, also decreased rapidly like Fe regardless of the pH values. This decrease in As concentration was mainly due to co-precipitation with ferrihydrite, and also partly to surface adsorption on goethite at low pH in drainage. Contrary to this observation, the concentration of other trace elements, such as Cd, Co, Zn, and Ni was greatly affected by the pH regardless of the mineral species. The lower the pH value, the higher the concentration of these trace elements were observed in the drainage, and vice versa at higher pH. These results indicate that the behavior of trace elements present as cations is more greatly affected by the mineral surface charge influenced by the pH values than the type of the precipitated mineral.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.6
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• pp.197-211
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• 2021

In the service industry the types are diversifying and the scale of service companies is greatly improving. Such a phenomenon is caused by economic growth and technological development diversifying consumer needs creating demand for new services maturing the service industry and intensifying competition among companies in the form of global competition. It can be said that this is because it is necessary to improve competitiveness by utilizing the economy of scale. Research is needed on the impact of entrepreneurship on various outcome variables in order for service organization managers to respond quickly to diverse and rapidly changing environments and achieve organizational outcomes and corporate goals of management outcomes. The purpose of this study was to empirically analyze the relationship in which the entrepreneurial spirit of a manager influences the relationship between customer orientation, which is an organizational result, customer satisfaction, and financial result, which is a management result. In order to verify such research, the questionnaire was composed of one business owner questionnaire, two employee questionnaires, and two customer questionnaires. The questionnaire was distributed to a total of 400 companies, and the questionnaires of 340 companies were collected. Of these, 303 companies, excluding the questionnaires of 37 companies with many dishonest or missing values, were used for hypothesis testing. The results of this study can be summarized as follows. First, entrepreneurship had a positive (+) effect on customer orientation, supporting the hypothesis. Second, customer orientation showed a positive (+) effect on customer satisfaction, supporting the hypothesis. Third, customer satisfaction showed a positive (+) effect on financial outcomes, supporting the hypothesis. Fourth, it was found that entrepreneurship influences customer satisfaction through customer orientation, and customer satisfaction affects financial outcomes. It turns out that customer orientation between entrepreneurship and customer satisfaction is completely mediated, and customer satisfaction is completely mediated by customer orientation and financial outcomes. The relationship between entrepreneurship and management improved employee behavior and attitudes, which is an individual outcome, and this change was found to improve customer satisfaction, which is an organizational outcome. It makes frequent contact with customers in the process of servicing them. Employee roles are important at service contacts and influence service purchases. Employees facing customers through service contacts act as a decisive factor in maintaining a continuous relationship with customers. Within a beauty service company, it is necessary to create a customer-oriented environment among workers. It suggests that customer-oriented companies and employees can anticipate their desires and provide products or services of superior value to achieve greater customer satisfaction and a competitive advantage. In addition, it was clarified that customer satisfaction has an aspect relationship with financial management, which is a management result. Therefore, it is suggested that the entrepreneurial spirit is an important factor for the management of a beauty service company to secure competitiveness and improve results.

• Korean Journal of Ecology and Environment
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• v.55 no.3
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• pp.231-243
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• 2022

Anthropogenic disturbances on freshwater ecosystem are known to degrade biodiversity, especially on fish assemblage. In this study, we have conducted fish surveys to identify impact of a bridge construction on fish assemblages. A total of eight study sites were surveyed in the Danjang and the Dong Stream in southern part of South Korea from June to November in 2021. The fish samplings were carried out five times, using cast-nets(10×10 mm mesh size), scoop-nets(4×4 mm, 5×5 mm mesh size), set-nets (10×10 mm mesh size), and fish traps (3×3 mm mesh size), along with the Stream/River Ecosystem Survey and Health Assessment by the Ministry of Environment of Korea and basic water quality measurement. Also, we applied the species diversity index and length-weight relationship regressions on certain species to identify interspecific growth rate differences in accordance with study sites. As a result, a total of 782 individuals, 23 species and 10 families were collected. The dominant species was Zacco Koreanus and relative abundance was 50.89%. When applying the length-weight relationship regressions on certain species, the 'b' value for Z. Koreanus was lower at the downstream points than at the upstream points of the construction site. In addition, when comparing to the results of the past survey, relative density of demersal fish at the upstream and downstream points decreased from 26% to 1.4%, and from 18% to 6.3%, respectively. In conclusion, it is considered that bridge construction negatively affects the habitat of fishes, especially on demersal fishes. Therefore, appropriate conservation efforts such as installation of silt protector and sand sedimentation pond are needed to alleviate the disturbance in habitat such as occurrence of turbidity and destruction of micro-habitats.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.4
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• pp.215-221
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• 2022

This study was carried out to investigate the growth characteristics, yield and chemical compositions of rye according to mixing ratio of chemical fertilize r(CF) and liquid swine manure (LSM) in paddy field cultivation. The experimental design was arranged in a randomized block design with three replications. The manure fertilizer ratio of five treatments were CF 100% + LSM 0% (C), CF 70% + LSM 30% (T1), CF 50% + LSM 50% (T2), CF 30% + LSM 70% (T3), and CF 0% + LSM 100% (T4) of rye. At this time, the application of liquid swine manure was based solely on nitrogen. Plant length did not show significant differences among treatments. Ear length, leaf length and leaf width were the longest in C, T3, and T2, respectively (p<0.05). The stem diameter showed in the order of T4 > T3 > T2 > T1 > C, which was thicker as the LSM application rate increased (p<0.05). Fresh, dry matter and total digestible nutrient (TDN) yield were the highest in T4 (p<0.05), whereas the lowest in C treatment. Crude protein, neutral detergent fiber (NDF), acid detergent fiber (ADF) and crude fiber content were did not show significant difference among treatments. However, compared to C, crude fat and crude ash were significantly higher in T2 and T3, respectively (p<0.05). Total mineral content decreased significantly as the LSM application rate increased (p<0.05). Total free sugar showed high in T3 and T4 with a high LSM ratio, but showed significantly lower in chemical fertilizer treatment (C) and low LSM treatment (T1) (p<0.05). The analysis of all the above results suggests that the application of LSM is very effective, considering the dry matter yield and the contents of free sugar. In addition, LSM may be possible to grow rye without chemical fertilizer.

• Journal of Wetlands Research
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• v.25 no.2
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• pp.75-82
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• 2023

Data for measuring the flow rate of streams are used as important basic data for the development and maintenance of water resources, and many experts are conducting research to make more accurate measurements. Especially, in Korea, monsoon rains and heavy rains are concentrated in summer due to the nature of the climate, so floods occur frequently. Therefore, it is necessary to measure the flow rate most accurately during a flood to predict and prevent flooding. Thus, the U.S. Geological Survey (USGS) introduces 1, 2, 3 point method using a flow meter as one way to measure the average flow rate. However, it is difficult to calculate the average flow rate with the existing 1, 2, 3 point method alone.This paper proposes a new 1, 2, 3 point method formula, which is more accurate, utilizing one probabilistic entropy concept. This is considered to be a highly empirical study that can supplement the limitations of existing measurement methods. Data and Flume data were used in the number of holesman to demonstrate the utility of the proposed formula. As a result of the analysis, in the case of Flume Data, the existing USGS 1 point method compared to the measured value was 7.6% on average, 8.6% on the 2 point method, and 8.1% on the 3 point method. In the case of Coleman Data, the 1 point method showed an average error rate of 5%, the 2 point method 5.6% and the 3 point method 5.3%. On the other hand, the proposed formula using the concept of entropy reduced the error rate by about 60% compared to the existing method, with the Flume Data averaging 4.7% for the 1 point method, 5.7% for the 2 point method, and 5.2% for the 3 point method. In addition, Coleman Data showed an average error of 2.5% in the 1 point method, 3.1% in the 2 point method, and 2.8% in the 3 point method, reducing the error rate by about 50% compared to the existing method.This study can calculate the average flow rate more accurately than the existing 1, 2, 3 point method, which can be useful in many ways, including future river disaster management, design and administration.