• Journal of Science Education
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• v.36 no.1
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• pp.153-165
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• 2012

This study investigated the frequent mistakes and the causes of the alternative conceptions in the animal classification by using the questionnaire and interview with the middle school students (N=300). As results, some students have difficulties classifying suggested animals into vertebrates or invertebrates : snakes (31.7%), shrimps (28.3%), turtles (25.6%), frogs (24.7%), and starfish (10.7%) in order of precedence. These errors seemed to be caused by intuitive thinking over characteristics of physical motions and appearance of suggested animals, wrong inference from comparing to features of familiar animals and the lack of observation experience of the vertebrate backbone. Furthermore, the results showed that relatively many students made a mistake classifying subgroup members of vertebrates such as classifying salamanders into the class Reptilia (45.3%) and turtles into Amphibia (40.3%). It is likely that those errors are affected by ambiguousness of classification terminology (e.g. the term of Amphibia) and weak ability in relating the physiological and ecological feature to standard of classification feature. In addition, sociocultural factors could influence animal classification as 'bat in birds', 'whale in fish, and 'penguin in mammals'. The present study implied that teaching and learning animal classification may require an appropriate guide focused on activities to explore major characteristics used for the animal classification standard through providing more chances of animal observation rather than the cramming method of learning induced by technical memorizing.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.263-273
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• 2020

In this study, in order to confirm the ameliorative effects of onion (Allium cepa L.) flesh and peel on amyloidbeta (Aβ)-induced cognitive dysfunction, we evaluated their in vitro neuroprotection and in vivo cognitive functions. As the result of in vitro neuroprotection, the protective effect of the ethyl acetate fraction of onion flesh (EOF) on Aβ-induced cytotoxicity was similar to that of the ethyl acetate fraction of onion peel (EOP). In the behavioral tests, the EOF and EOP effectively improved the Aβ-induced learning and memory impairments. For this reason, it could be concluded that the EOF and EOP improved the antioxidant activities (superoxide dismutase, oxidized glutathione/total glutathione, and malondialdehyde) in brain tissue. In addition, the EOF and EOP effectively activated mitochondrial functions by protecting the mitochondrial membrane potential, ATP, mitochondria-mediated protein (BAX and cytochrome c), and caspase 3/7 activities. The EOF and EOP also improved the cholinergic system (acetylcholinesterase and acetylcholine). Therefore, we suggest that onion could be used for management of Aβ-induced cognitive dysfunction.

• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.1008-1017
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• 2004

In physics education, language is an fundamental learning tool as in other subjects. In writing activity, students can get fair opportunities to express their own ideas during the class. Even though there are various styles of writing, students are usually supposed to make a report in their science classes. But there have been few studies in science education on the tasks and features of student's science writing. In this research, different styles of writing tasks were designed for science classes, and students' writing was analysed in terms of conceptual and emotional aspects. Also the usefulness of each task type was discussed relating to school physics education. Four types of writing, i.e. , , , and writing were developed, and 'The reflection of light' was selected as the theme and given to students. Four types of writing were analysed in this paper. In each type of writing, students showed different features in their conception. They also showed emotional expressions in imaginative writing types, that is, and types. Based on these results, it is recommended that in physics teaching various types of writing need to be designed, developed and applied according to the aim of a particular lesson.

• Korean Journal of Acupuncture
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• v.22 no.4
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• pp.67-81
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• 2005

Objectives : Cervus Elaphus(CE) has been used to medication for ischemic stroke in the Oriental Medicine. So this study was planned to investigate the effects of CE herbal acupuncture therapy(CE-HAT) on the focal ischemia-induced by intraluminal filament insertion in the rats. Materials and methods : The focal ischemia was induced by middle cerebral artery occlusion for 2hours. The groups divided into 6 groups, normal(intachess group), control(no theray group after ischemia-induced), CE-HAT1(Cervus Elaphus-herbal acupuncture therapy group at LR1, HT9 after ischemia-induced), CE-HAT2(Cervus Elaphus-herbal acupuncture therapy group at LU8, KI7 after ischemia-induced), CE-HAT3(Cervus Elaphus-herbal acupuncture therapy group at LR1, HT9, LU8, KI7 after ischemia-induced), CE-HAT4(Cervus Elaphus-herbal acupuncture therapy group at LR1, HT9, HT3, KI10 after ischemia-induced). CE-HAT was carried out during 3 weeks after focal ischemia-induced. Eight-arm radial maze was used for the behavioral task and neuropretective effect of CE-HAT was observed by Cresyl violet, AchE, ChAT-stain. Results : The error rate in the eight-arm radial maze task was significantly decreased in CE-HAT1, CE-HAT2, CE-HAT4 on 3days, CE-HAT4 on 4days, CE-HAT2, CE-HAT4 on 5days, CE-HAT3, CE-HAT4 on 6days. The rate of correct choice was significantly increased in CE-HAT4. The density of neurons in the hippocampal CA1 was significantly increased in CE-HAT1, CE-HAT2, CE-HAT3, CE-HAT4, compared to control group. The density of ChAT in the hippocampal CA1 was significantly increase in CE-HAT4. The density of ChAT in the hippocampal CA1 was significantly increased CE-HAT1. Conrlusions : These results suggest that the Cervus Elaphus-herbal acupuncture therapy could be used as a medication for controlling the stroke induced by deficiency.

• Communications of Mathematical Education
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• v.13 no.1
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• pp.73-96
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• 2002

수학적인 사고력과 창의력이 강조되고 있는 요즈음 수학교육에서는, 이산수학적인 영역이 담당해야 할부분이 더욱 많아진 것으로 생각된다. 이에 발맞춰, 최근에 이산수학에 관한 연구가 활발해지고 있다. 그러나, 아직 초등학교에서 적절히 사용할 수 있는 별도의 이산수학 관련 서적이나 연구 문헌이 없어 아동들의 이산수학에 대한 관심과, 수학 성적과 이산수학의 문제 해결력과의 관계에 대하여 조사해 보았다. 이산수학의 문제들을 구성하여 아동들에게 예고 없이 평가하고 문제에 대한 수학적인 태도를 질문을 통하여 알아보고, 수학 실력이 우수한 학생과 그렇지 못한 학생들과의 이산수학 문제 해결력의 관계를 알아보고자 다음과 같은 연구 내용을 설정하였다. 이를 살펴보면 첫째, 초등 수학교육에서 이산수학에 대한 학생들의 반응에 대하여 생각해 본다. 둘째, 수학 성적과 이산수학 문제 해결과의 관계를 생각해 본다. 이상의 연구 문제를 해결하기 위해, 문헌 연구를 통하여 이산수학에 관련된 초등학교 내용을 소개하고, 문항을 구성하였다. 소개된 주제 중에서 4개의 주제(수 세기, 한 붓 그리기, 지도 색칠하기, 최소 거리 ${\cdot}$ 비용 수형도)를 선정하여 10개의 문항을 작성하였다. 조사 연구를 위한 대상은 서운 시내 2개 초등학교 5, 6학년 2개 반을 선정하였다. 각 문항의 정답율은 백분율(%)에 의하여 분석하였는데 그 결과를 살펴보면, 첫째, 수 세기의 정답율은 첫 번째 문항의 정답율이 낮았을 뿐, 다른 문항들의 정답율은 비교적 좋게 나타난 것으로 보아 문제를 이해하기 쉽게 구성하는 것이 중요하다는 것을 알게 되었다. 둘째, 한 붓 그리기와 지도 색칠하기의 문제들의 정답율은 상당히 높게 나타났는데, 그러한 것은 아동들이 직접 다양한 방법으로 시도해 봄으로써 문제를 해결할 수 있었기 때문인 것 같다. 또한 이러한 유형의 문제들은 아래 학년에도 투입해 볼 수 있을 것 같다. 셋째, 최소거리 ${\cdot}$ 비용 수형도의 문제에서는 난이도가 높은 이유도 있지만 문제 이해를 완전히 하지 못해 정답율이 무척 낮게 나온 것으로 생각된다. 넷째, 수학 성적이 높은 학생들이 대체적으로 문제 해결력이 높았던 것으로 나타났으나, 몇몇 학생들은 정반대의 결과가 나와 특이한 시사점을 제공했다. 그러한 이유로는 정형화된 문제들을 선호하고 쉽게 해결하는 아동들과, 그렇지 않은 아동들 사이의 문제 접근 방법의 차이라고 생각된다. 본 연구를 통하여 다음과 같은 제언을 하고자 한다. 첫째, 이산수학에 관련된 많은 문항을 개발하여 아동들에게 확대 투입함으로써 수학 수업의 효과와 문제 해결력을 높일 수 있을 것이라 생각된다. 둘째, 수학 실력이 떨어지는 아동들에게 보다 흥미있는 이산수학적 문제들을 제시함으로써 수학에 대한 자신감과 흥미를 높일 수 있을 것이라 생각된다. 셋째, 초등학교 과정에 알맞은 이산수학의 다른 주제도 학습 지도안과 그와 관련된 문제들을 개발하는 연구가 진행되어야 하겠다.

• Korean Journal of Childcare and Education
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• v.10 no.2
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• pp.111-131
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• 2014

This study aims to research the use of smart devices of infants and preschool children, and their mothers' perception about it. Moreover, the goal of this study is to collect preliminary data about problems from the use of smart devices, and to prevent the problems. Therefore, the questions of inquiry for this study are: 1. How do infants and preschool children use smart devices? 2. How do mothers perceive their children using smart devices? Four hundred and forty mothers, who send their child to a day-care center or kindergarten in Busan, participated in this research and data among 397 of them were analyzed using PASW 18.0 program. The answers to a multiple-choice question were converted into a frequency and percentage. To verify the difference of factors, Chi-squared Test and One-way Analysis of Variance methods were used. The following are findings of this study: 1. Most of the families owning smart devices allow their children to use a smart device when children want it, and children use it for entertainment purpose before their bedtime. Children start to use a smart device mostly around the age of 4. Compared to girls, boys spend a longer time on smart devices playing mobile game. In addition, the research indicated that the children of younger mothers tend to use smart devices in earlier ages than the children of elder mothers. 2. Mothers of preschool children have higher perception about the availability of their child using smart devices compare to the mothers of day-care center. However, the research showed that elder mothers have more positive perceptions about all the other five lower factors, (e.g. educational characteristic, entertainment characteristic, design, safety, and smart recognition).

• Journal of The Korean Association For Science Education
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• v.33 no.2
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• pp.390-404
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• 2013

The premise of the study is that teacher communities or teacher interest groups are one of the representative examples of Communities of Practice (CoP) formed by teachers who engage in the process of collective learning regarding science teaching. Based on the theory of CoP, we investigated and interpreted the process of identity development of six science teachers who have been actively involved in teacher communities. We conducted 2-3 individual interviews with the teachers in order to explore their narratives and personal experiences of being involved in the communities over the years. Results indicated that a teacher community is a place where the teachers not only generated and shared repertories of ideas, documents on teaching and learning, or routines (i.e. practices), but also formulated a set of relationships through social participation. Teacher communities actively provide the teachers a sense of joint enterprise and identity, and where the teachers have an opportunity to develop themselves personally and professionally as science teachers playing major roles in their communities.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.8
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• pp.535-542
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• 2013

Since case-based reasoning(CBR) has many advantages, it has been used for supporting decision making in various areas including medical checkup, production planning, customer classification, and so on. However, there are several factors to be set by heuristics when designing effective CBR systems. Among these factors, this study addresses the issue of selecting appropriate neighbors in case retrieval step. As the criterion for selecting appropriate neighbors, conventional studies have used the preset number of neighbors to combine(i.e. k of k-nearest neighbor), or the relative portion of the maximum similarity. However, this study proposes to use the absolute similarity threshold varying from 0 to 1, as the criterion for selecting appropriate neighbors to combine. In this case, too small similarity threshold value may make the model rarely produce the solution. To avoid this, we propose to adopt the coverage, which implies the ratio of the cases in which solutions are produced over the total number of the training cases, and to set it as the constraint when optimizing the similarity threshold. To validate the usefulness of the proposed model, we applied it to a real-world target marketing case of an online shopping mall in Korea. As a result, we found that the proposed model might significantly improve the performance of CBR.

• Management & Information Systems Review
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• v.36 no.2
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• pp.187-206
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• 2017

This study empirically investigated the direct and indirect effects of inter-organizational relationships control mechanisms (IRCM; prudent partner selection and complex contract) on the decrease of inter-organizational risks (i.e., relational risk and performance risk). The empirical results showed that prudent partner selection has a positive impact on the degrees of inter-organizational cooperation and the levels of inter-organizational information flow. The effects of complex contract on the inter-organizational cooperation and information flow were not significant. In the results of the decrease of inter-organizational risks, it was observed that inter-organizational cooperation has significant positive effects on the decrease of both relational risk and performance risk. It was found that partner selection only influences the decrease of performance risk. The impact of inter-organizational information flow on the decrease of inter-organizational risks was not statistically significant. The indirect effects of IRCM on the decrease of performance risk through inter-organizational cooperation were also empirically demonstrated. The significant impact of inter-organizational cooperation on the decrease of risks implies that high levels of collaborations among employees decrease the risk of opportunistic behavior as well as the possibility of low degrees of performance through cooperative efforts. According to the results of the effects of risks on supply-chain performance, only the impact of performance risk was negatively significant. This result points out that the low levels of performance cause delays in delivery and product launch, deterred production and delayed market response, and these deteriorated managerial activities necessarily decrease the degrees of supply-chain performance.

• Journal of IKEEE
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• v.19 no.2
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• pp.237-243
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• 2015

Recently, eight out of ten people have smartphone in Korea. Also, many applications of smartphone have increased. So, smartphone addiction has become a social issue. Especially, many people in smartphone addiction can't control themselves. Sometimes they don't realize that they are smartphone addiction. Many studies, mostly surveys, have been conducted to diagnose smartphone addiction, e.g. S-measure. In this paper, we suggest how to detect smartphone addiction based on ECG and Eye Gaze. We measure the signals of ECG from the Shimmer and the signals of Eye Gaze from the smart eye when the subjects see the emotional video. In addition, we extract features from the S-transform of ECG. Using Eye Gaze signals(pupil diameter, Gaze distance, Eye blinking), we extract 12 features. The classifier is trained using Random Forest. The classifiers detect the smartphone addiction using the ECG and Eye Gaze signals. We compared the detection results with S-measure results that surveyed before test. It showed 87.89% accuracy in ECG and 60.25% accuracy in Eye Gaze.