• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.60-61
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• 2003

A new approach to reduce the computation time of genetic algorithm (GA) for making binary phase holograms is described. Synthesized holograms having diffraction efficiency of 75.8% and uniformity of 5.8% are proven in computer simulation and experimentally demonstrated. Recently, computer-generated holograms (CGHs) having high diffraction efficiency and flexibility of design have been widely developed in many applications such as optical information processing, optical computing, optical interconnection, etc. Among proposed optimization methods, GA has become popular due to its capability of reaching nearly global. However, there exits a drawback to consider when we use the genetic algorithm. It is the large amount of computation time to construct desired holograms. One of the major reasons that the GA' s operation may be time intensive results from the expense of computing the cost function that must Fourier transform the parameters encoded on the hologram into the fitness value. In trying to remedy this drawback, Artificial Neural Network (ANN) has been put forward, allowing CGHs to be created easily and quickly (1), but the quality of reconstructed images is not high enough to use in applications of high preciseness. For that, we are in attempt to find a new approach of combiningthe good properties and performance of both the GA and ANN to make CGHs of high diffraction efficiency in a short time. The optimization of CGH using the genetic algorithm is merely a process of iteration, including selection, crossover, and mutation operators [2]. It is worth noting that the evaluation of the cost function with the aim of selecting better holograms plays an important role in the implementation of the GA. However, this evaluation process wastes much time for Fourier transforming the encoded parameters on the hologram into the value to be solved. Depending on the speed of computer, this process can even last up to ten minutes. It will be more effective if instead of merely generating random holograms in the initial process, a set of approximately desired holograms is employed. By doing so, the initial population will contain less trial holograms equivalent to the reduction of the computation time of GA's. Accordingly, a hybrid algorithm that utilizes a trained neural network to initiate the GA's procedure is proposed. Consequently, the initial population contains less random holograms and is compensated by approximately desired holograms. Figure 1 is the flowchart of the hybrid algorithm in comparison with the classical GA. The procedure of synthesizing a hologram on computer is divided into two steps. First the simulation of holograms based on ANN method [1] to acquire approximately desired holograms is carried. With a teaching data set of 9 characters obtained from the classical GA, the number of layer is 3, the number of hidden node is 100, learning rate is 0.3, and momentum is 0.5, the artificial neural network trained enables us to attain the approximately desired holograms, which are fairly good agreement with what we suggested in the theory. The second step, effect of several parameters on the operation of the hybrid algorithm is investigated. In principle, the operation of the hybrid algorithm and GA are the same except the modification of the initial step. Hence, the verified results in Ref [2] of the parameters such as the probability of crossover and mutation, the tournament size, and the crossover block size are remained unchanged, beside of the reduced population size. The reconstructed image of 76.4% diffraction efficiency and 5.4% uniformity is achieved when the population size is 30, the iteration number is 2000, the probability of crossover is 0.75, and the probability of mutation is 0.001. A comparison between the hybrid algorithm and GA in term of diffraction efficiency and computation time is also evaluated as shown in Fig. 2. With a 66.7% reduction in computation time and a 2% increase in diffraction efficiency compared to the GA method, the hybrid algorithm demonstrates its efficient performance. In the optical experiment, the phase holograms were displayed on a programmable phase modulator (model XGA). Figures 3 are pictures of diffracted patterns of the letter "0" from the holograms generated using the hybrid algorithm. Diffraction efficiency of 75.8% and uniformity of 5.8% are measured. We see that the simulation and experiment results are fairly good agreement with each other. In this paper, Genetic Algorithm and Neural Network have been successfully combined in designing CGHs. This method gives a significant reduction in computation time compared to the GA method while still allowing holograms of high diffraction efficiency and uniformity to be achieved. This work was supported by No.mOl-2001-000-00324-0 (2002)) from the Korea Science & Engineering Foundation.

• Korean Journal of Optics and Photonics
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• v.28 no.5
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• pp.203-212
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• 2017

A scientific model refers to a conceptual system that can describe, explain, and predict a particular physical phenomenon. The co-construction of the scientific model is attracting attention as a new teaching and learning strategy in the field of science education and various studies. The evaluation and modification of models compared with the predicted models of data from the real world is the core of modeling strategy. However, there were only a limited data provided by the teacher in many studies of modeling comparing the students' predictions of their own models. Most of the students were not given the opportunity to evaluate the suitability of the model with the data in the real world. The purpose of this study was to develop a scientific model co-construction program that can evaluate the model by directly comparing the predicted models with the observed data from the real world. Through a collaborative discussion between teachers and researchers for 6 months, a 5-session scientific model co-construction program on the subject 'image formation by convex lenses' for second grade middle school students was developed. Eighty (80) students in 3 classes and a science teacher with 20 years of service from general public co-educational middle school in Gyeonggi-do participated in this 2-week program. After the class, students were asked about the helpfulness and difficulty of the class, and whether they would like to recommend this class to a friend. After the class, 95.8% of the students constructed the scientific model more than the model using the construction rule. Students had difficulties to identify principles or understand their friends, but the result showed that they could understand through model evaluation experiment. 92.5% of the students said that they would be more than willing to recommend this program to their friends. It is expected that the developed program will be applied to the school and contribute to the improvement of students' modeling ability and co-construction ability.

• Journal of Christian Education in Korea
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• v.67
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• pp.45-75
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• 2021

The purpose of this study is to explore a new paradigm for Bible didactics in the context of the contemporary times and it turns its gaze to the midrash, the old tradition of Hebrew Bible interpretation. In order for the current Bible study to be meaningful and effective in today's situation, it is an effort to connect the Bible and us well, more than educational contents or materials. The word "midrash" itself means "textual interpretation", or "study", derived from the root verb darash, which means "to seek," "to seek with care," "to enquire," "to require" forms of which appear frequently in the Hebrew Bible. Midrash means an exegesis and interpretation of the Hebrew Bible (Torah) as well as a group of works that are the result of specific interpretations of the rabbis. This rabbinical tradition provides specific interpretative guidelines dealing with the Bible. These interpretive guidelines were passed down and formed an attitude of interpreting the Bible that is still relevant today. The rabbinical interpretative guidelines in midrash lead to the discovery of the following biblical didactical meanings. First, the Bible requires an attitude of listening and learning. Second, an attitude of inquiry is needed. Third, an exploration through the empty space is essential. Fourth, it leads us to recognize the importance of mutual respect and communication. Fifth, through the Words that challenge me, the meaning of biblical teaching is discovered. These interpretation guidelines have much in common with Bibliodrama, which applies midrash to the didactic of Bible. Bibliodrama is a dramatic inquiry, where the effect of in-depth inquiry and consideration that midrash aimed at can be expected. In addition, bibliodrama is a process of communal interaction that leads to a new experience and a richer understanding of the Bible through different positions and viewpoints. Exploring the "white fire" of the Bible, we listen to what God says to us, which causes us to change and form an identity. The biblical didactical meaning found in midrash's interpretation guidelines and the biblical didactical application of midrash through the bibliodrama can be presented as a new alternative to Christian education for the past, the present and the future. This will be able to present a new paradigm for biblical didactics with the word of God living and working in the present, not the Bible of the past, which is far from our present life.

• 대한공업교육학회지
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• v.44 no.1
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• pp.52-71
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• 2019

The quality of school education is a key element for national education development. An important factor that determines the quality of school education is qualities of teachers who are in responsible for school education in the field. Therefore, it is necessary to hire competent teachers in the teacher appointment exam for the secondary school. This necessity is evident especially for vocational high schools and Meister high schools with the introduction of 2015-revised curriculum based on NCS that separates each three subjects, "Electrical, Electronics Communication" resulting in the change of question mechanism, which requires new designing of assessment and content area. So, this study analyzes curriculum in college of education for "Electrical", "Electronics", "Communication", 2015-revised curriculum based on NCS and the development of standards for teacher qualifications and assessment area and evaluation of teaching ability in the subjects of the teacher appointment exam, "Electrical, Electronics Communication" Engineering" in 2009. The assessment area and content elements of "Electrical", "Electronics", "Communication are extracted from the analyzed results and they are verified by experts' consultation and presented as follows; First, the assessment area and content elements of the "Electrical" subject were designed to evaluate the NCS - based 2015 revised curriculum by presenting the NCS learning module to the evaluation area and content element in the basic subject "Electrical and Electronics Practice". Second, the section of "Electronics" presented the assessment area and content elements applying the Electronic Circuit, basic subject of the NCS and it also added "Electromagnetics", which is the basic part of Electronics in the Application of Electromagnetic waves that could be applied to the assessment. Third, the assessment area and content elements of "Communication" consist of the communication-related practice that is based on "Electrical" and "Electronic", considering the characteristics of "Communication Engineering". In particular, "Electrical and Electronics practice" which adds network construction practice and communication-related practice makes it to be able to evaluate the communication-related practical education.

• Journal of The Korean Association For Science Education
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• v.38 no.6
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• pp.765-780
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• 2018

The purpose of this study is to synthesize the theoretical perspectives, research methods, and research results of teachers' professional vision by reviewing and analyzing previous research papers and to suggest implications for science teacher education and research. Three databases were used to search peer reviewed journal articles published between 1997-2017, which include 'teachers' and 'professional vision' explicitly in abstracts and empirical studies only. 21 articles in total were analyzed and review results are as follows. First, researchers regarded professional vision as a new concept of teacher professionalism. Previous research viewed professional vision as integrated structure of teachers' knowledge or ability activated at specific moment. Second, the analytical framework of professional vision included two aspects; 'selective attention' and 'reasoning'. Several aspects of lessons or the desirable teaching and learning factors are suggested as the subcategories of selective attention. Hierarchical levels or independent reasoning ability factors are suggested as the subcategories of reasoning process. Third, research on teachers' professional vision focused more on middle school teachers than elementary teachers and on various subject areas. Most studies used video clips and more cases of using videos of non-participants were found. In case of measurement of professional vision, most quantitative scoring methods were whether the responses of experts and teachers on video clips were consistent. Last, most studies examined or assessed teachers' professional vision. It is reported that in-service teachers' professional vision was evaluated higher than novice teachers' and using video clips were effective to examine and improve teachers' professional vision.

• Journal of Korean Home Economics Education Association
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• v.33 no.3
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• pp.85-105
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• 2021

The purpose of this study is to develop and implement cooperative consumption education programs using design thinking in middle school home economics education classes to understand the impact on students' cooperative problem solving competency. Accordingly, a cooperative consumption education program based on design thinking was developed according to the ADDIE model, and the evaluation was conducted on a total of 25 students. The results of the study were as follows. First, based on prior research, we developed a consumption education program based on D. school's design thinking process under the theme of 'Creating a Shared School' for the practice of cooperative consumption. As a result of expert validity verification of the teaching/learning course plan and workbook for the eight sessions, the average question was 4.72 (out of 5 points) and the average CVI was 0.93, indicating that the content validity and field suitability were excellent. Second, to summarize the results achieved from the implementation of the cooperative consumption education program, the pre-/post-test using the revised and supplemented cooperative problem-solving competency tool, and the open-ended survey, It was confirmed that the developed program had a significant effect on improving not only the students' knowledge and perceived necessity for cooperative consumption along with the awareness of practice, but also the cooperative problem-solving competency. As a follow-up study, we propose to expand the research to a wider audience, and to further conduct research and develop programs applied with design thinking in home economics curriculum and in consumer competency development. This study confirmed that cooperative consumption education programs using design thinking are effective in improving youth's cooperative problem-solving competency and is meaningful in that they developed consumption education programs under the theme of 'cooperative consumption' in response to changing consumer education needs.

• The Journal of Korean Philosophical History
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• no.23
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• pp.317-347
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• 2008

Huang Gan(1152 - 1220, pen-name Mian-zhai) was a famous scholar of Zhu-zi xue in the Southern Song period. Zhu-zi xue was also called Daoxue(道學), because it was based on the Cheng-Zhu xue(程朱學) and had very severe idea of Daotong(道統). Therefore, Zhu-zi xue emphasized practical movements of spreading Confucianism. The view of the Daotong(道統) developed in two aspects: protection of Confucianism and exclusion of Daoism Buddhism. Zhu Xi completed the idea of Daotong(道統), and his disciples, especially Huang Gan, continued his efforts. Zhu Xi's disciples searched the ultimate teaching of Confucianism through studying Four-books(四書). In due of their effort, Zhu-zi xue played a reading role in those academic fields. Huang Gan look upon himself as the successor to Zhu-zi xue. He expounded and missionized Zhu Xi's philosophical thought. In his later years, he accepted many students and passed the Zhu Xi's thought on to his students. He fostered "Jin-hua school(金華學派)"-He Ji(何基), the representative of this school. There is the relation of thought on the theory of knowledge and learning centering around Daotong between Huang Gan and Jin-hua school(金華學派). Especially, the most schools leading the academic society of Yuan period founded their thought on Huang Gan's. And it explained Huang Gan's historical influence and contributions to the Zhu-zi xue in the Yuan period.

• The Journal of Korean Philosophical History
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• no.32
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• pp.79-112
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• 2011

Since Noron(老論) had organized in the period of Sookjong(肅宗), it constantly had led the political situation of Choson until Choson(朝鮮) perished as the grasping political power. Studies and thoughts development of Noron can be devided into four periods. First, the term of politics of faction of the period of Sookjong. Second, a period of Youngjo(英祖) and Joungjo(正祖). Third, a period of politics of power(勢道政治). Fourth, the latter term of 19century. We can look into an origin and development aspect in outline by dividing like this. The general character of Noron can be summarized by the respect of Song Si-yeol(宋時烈, 1607-1689), the theory of a party of a man of virtue(君子黨論) based on the theory of moral civilization of Choson(朝鮮中華論), the succession of Lee i(李珥; 1636-1684)'s neo-confucianism, rejecting all teaching that does not conform to neoconfucianism and protecting right studies, and oppression of Roman Catholic. The noticeable scholars of Noron were Kwon sang Ha(權尙夏; 1641~1721), Kim chang hyup(金昌協; 1651~1708), Lee jea(李縡; 1680~1746) etc. These scholars of Noron following Song Si-yeol had tried to raise "Learning of the Way"(正明道) by respecting Zushi and removing injustice(尊朱子攘夷狄), also believed people should embody moral values in their society and country. and possessed an will guiding to stabilize the country by rejecting uncivilization(尊王攘夷). Above all, they insisted, the King of Choson should rule with 'lighting heavenly reason'(明天理). Also they insisted the King and countrymen should together strive to recover civilization of moral humanity and destroy uncivilzation. But gradually they lost the motive and purpose of moral politics in the seventeenth century. Finally Noron Byeokpa(?派) take over the reins of government. It resulted in the bad effect of politics of autocrat(勢道政治) having their own way to use power of authority after death of Jungjo(正祖). The peculiar character of Noron politics can valued as the extreme aspect of 'according of politics and scholarship'(政學一致).

• Journal of Nutrition and Health
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• v.55 no.1
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• pp.21-35
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• 2022

The recommended meal composition allows the general people to organize meals using the number of intakes of foods from each of six food groups (grains, meat·fish·eggs·beans, vegetables, fruits, milk·dairy products and oils·sugars) to meet Dietary Reference Intakes for Koreans (KDRIs) without calculating complex nutritional values. Through an integrated analysis of data from the 6th to 7th Korean National Health and Nutrition Examination Surveys (2013-2018), representative foods for each food group were selected, and the amounts of representative foods per person were derived based on energy. Based on the EER by age and gender from the KDRIs, a total of 12 kinds of diets were suggested by differentiating meal compositions by age (aged 1-2, 3-5, 6-11, 12-18, 19-64, 65-74 and ≥ 75 years) and gender. The 2020 Food Balance Wheel included the 6th food group of oils and sugars to raise public awareness and avoid confusion in the practical utilization of the model by industries or individuals in reducing the consistent increasing intakes of oils and sugars. To promote the everyday use of the Food Balance Wheel and recommended meal compositions among the general public, the poster of the Food Balance Wheel was created in five languages (Korean, English, Japanese, Vietnamese and Chinese) along with card news. A survey was conducted to provide a basis for categorizing nutritional problems by life cycles and developing customized web-based messages to the public. Based on survey results two types of card news were produced for the general public and youth. Additionally, the educational program was developed through a series of processes, such as prioritization of educational topics, setting educational goals for each stage, creation of a detailed educational system chart and teaching-learning plans for the development of educational materials and media.

• Journal of the Korean earth science society
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• v.43 no.2
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• pp.312-323
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• 2022

This study began with the hypothesis of whether "solar radiation" and "terrestrial radiation" can be replaced by "visible radiation" and "infrared radiation", respectively. To this end, we investigated the perceptions of high school students who completed the Earth Science I course through a questionnaire to reveal how they perceived each concept. We also analyzed the descriptions and illustrations of textbooks that may have affected their perceptions. All of the students who participated in the questionnaire recognized solar radiation as radiation emitted only in the visible light region. About 35% of the students recognized convection, conduction, and latent heat as energy transfer by radiation in the Earth's heat budget. By analyzing six types of Earth Science I textbooks in the 2015 revised curriculum, we observed that two types introduced the terms "shortwave radiation" and "longwave radiation" but had no explanation for them, while the other two described solar radiation as "radiation mainly in the visible light region" or "radiation in short wavelengths". Regarding solar and terrestrial radiation in the last two types, there was no explanation for the wavelength regions, or ambiguous terms such as "short wavelength" and "long wavelength" were used. In addition, the two textbooks contained some errors in the illustration of the energy budget. Considering that textbooks described solar and terrestrial radiation without defining the exact terms for shortwave and longwave radiation, learners are likely to recognize solar and terrestrial radiation as visible and infrared radiation, respectively. This finding implies that vague statements or errors in textbooks can cause or reproduce students' misconceptions. The discussion in this study is expected to be used as a helpful reference material for teaching and learning processes regarding the Earth's radiation equilibrium and heat budget, and thereby contribute to proposing reasonable description plans for future textbook writing.