• Journal of The Korean Association For Science Education
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• v.11 no.2
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• pp.13-21
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• 1991

For development of teaching model for observational experiment and the major contents of science education guide books published for secondary school teacher in America, the actual survey to the secondary schools and the investigation of science education guide were carried out. The results were summarized as follows. 1. The major concepts of contents in science education books are constituted of introduction(9.67%), ability(8.94%), activity(6.61%), curriculum(11.61%), instruction planning(5.25%), instruction strategy(l7.74%), materials and facilities(1O.97%), evaluation(8.62%), society and community(l0.55%), guidelines(4.76%), practice(3.54%), and index(1.74%). 2. The constitution of multimedia teaching model for observational instruction was developed and arranged in order of six steps as observation, materialization, broad understanding, advanced study, application, and synthesis. This model was thought as the most effective for the achievement of the instructive goal for observational unit and others.

• Journal of The Korean Association For Science Education
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• v.8 no.1
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• pp.33-42
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• 1988

Secondary school students' conceptions about the phenomena of evaporating, condensing, boiling and melting of ice using a modified questionare-about-events method. The specific views at each grade level were also studied. The results of investigation were as following. 1) Students' understanding on the sciencific concepts and terms is superficial and nonscientific. 2) Even though upper grade students have exposed to a considerable science teaching, their views are similar to lower grade students. 3) Certain views on the change of state of water can change with the advanced science teaching. However, some nonscientific views are more popular with the older students than with the younger students.

• The KSFM Journal of Fluid Machinery
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• v.11 no.4
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• pp.7-13
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• 2008

The computational investigation is performed to find out the interaction of arc plasmas with surrounding materials and the thermal flow characteristics in a PASB (Puffer-Assisted Self-Blast) chamber, which is one of new breaking concepts in $SF_6$ switchgears. It is very important to define the flow and mass transfer happened during the full arcing history for further understanding complex physics inside the chamber. In this study, we have considered two diffusion processes by the hot arc plasma, one is PTFE nozzle ablation and the other is Cu electrode evaporation, simultaneously. It was found that the principle of the pressure-rise inside the chamber is confirmed by the computational results and the increase of the electrical conductivity of the residual gas near current zero is critical to the chamber design.

• Journal of The Korean Association of Information Education
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• v.15 no.4
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• pp.543-550
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• 2011

STEAM education is a topic-based curriculum to integrate the concepts into other subjects such as science, technology, engineering, art and mathematics in order to improve the students' interesting, understanding, integrated thinking and problem solving ability. In this paper, we designed STEAM curriculum in the form of Project-based Learning and developed the material for elementary students. We also developed the android-based application through searching for a utilization of IT simulation for enhancement the students' Project-based Learning effect.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.12
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• pp.3109-3120
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• 1996

SDL has been standardized to specify behavioral aspects of communication systems based on the formal description technique, and it is powerful and user friendly in the sense of supporting human communication and understanding, formal analysis andcomparison of behaviors, alternative implementations and design optimization, and its structural decomposition. However, SDL is not sufficient for an efficient handing of entrire system descriptions because the communication systems are generally very complex, and composed from the various interactions among sub-systems. Also, it is very difficult to explicitly verify dynamic views such as liveness and reachability. it leads the demands on analysis scheme to verify dynamic behaviros of specified systems. This paper presents modeling concepts of Petri Nets from SDL and transformation rules to Numerical Petri Nets to provide efficient technqiques for verification of dynamic behaviors, and proposes the reachability garaph that is able to trace all reachable states of a modeled system and reduce an information loss on the reachability tree.

• Journal of the Korean earth science society
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• v.27 no.7
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• pp.705-714
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• 2006

The purpose of this study was to explore the elementary students' perceptions of Earth systems and environmental issues. A survey was conducted to determine the students' perceptions on the following aveas: (1) the concepts of certainty and tangibility, (2) self-reported knowledge level, (3) perceived danger level of selected eight Earth systems and environmental issues, and (4) their primary information source on these issues. Results indicated that ozone hole, acid rain, El $Ni\widetilde{n}o$, and global warming were identified by the students as uncertain and intangible issues. Perceived certainty and perceived tangibility were highly positively correlated with self-reported knowledge compared to other relationships. The results also showed that learning from school was the most frequent information source for environmental issues. The second most frequently used source of information was television among several mass media sources. It is hoped that this study contributes to understanding the elementary school students' perceptions toward the selected Earth systems and environmental issues.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.10
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• pp.854-870
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• 2000

This survey paper presents and overview on eigenstructure assignment (EA) control design methodologies. EA is an excellent control design method which may be used to assign the entire eigenstructure(eigenvalues, and right or left eigenvectors) of a closed-loop linear system via a full state or an output feedback control law. In general, EA is well-sutied for incorporating classical specifications on damping, settling time, and mode or disturbance decoupling into a modern multivariable control framework. The purpose of this paper is to provide an extensive survey on EA control design methods that might serve as an introduction to a study on EA. The fundamental concepts and formulations for understanding EA problems are extensively described. The recently reported results on EA are also presented.

• The Mathematical Education
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• v.48 no.1
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• pp.93-105
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• 2009

Considering the fact that PCK(pedogogical content knowledge) tends to guarantee the identity of mathematics education as a discipline and the teacher professionalism, PCK is one of the core concepts in the research on subject matter education. The purpose of this study is to review domestic and international researches on the definition and the components of PCK in mathematics. Based on the review, this study identified 3 knowledges which consist PCK; knowedge of mathematic content, knowledge of learner's understanding, and knowledge of teaching. Then this study provided some examples of PKC in the topic, the limit of sequences, and introduced the LMT and TEDS-M items, which were designed to measure the teacher's PCK. Lastly, this study attempted to evaluate the items on mathematics education included in the Teacher Employment Test administered for pre-service/. teachers in Korea based on PCK.

• Korean Journal of Poultry Science
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• v.28 no.2
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• pp.165-172
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• 2001

Vaccination is one of the most important and cost-effective methods of preventing infectious diseases. Over the past decade, scientific in molecular biology and immunology have improved understanding of many diseases and led to the development of novel strategies for vaccination. An ideal vaccine would induce effective immunity specific for the type of infection, have long duration, require minimal or no boosters, have safety, would not induce adverse reaction, and be easy to administer. The desire to meet these criteria has resulted in the development of vaccines that do not depend on the use of the viable disease agent. It is not the intent of this review to give an extensive review of the field of vaccinology, but rather to address characteristics of conventional and genetically engineered vaccines.

• Korea-Australia Rheology Journal
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• v.18 no.1
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• pp.31-38
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• 2006

A systematic approach is employed to elucidate the interrelationships among macroeconomic entities such as science, engineering, technology, industry and national economy. Specifically, a conceptual, sequential method has been developed to clearly identify the essential ingredients needed for each macroeconomic entity starting from science to transform to the next one, and all the way to the national economy where the production of added-value is of overriding importance. The results thus obtained can then be utilized for macroeconomists to readily apply the engineering theory and knowledge to various macroeconomics situations, while engineers can likewise utilize the results on top of the microeconomic knowledge already prevalent in many engineering fields in getting better grasp of the seemingly difficult nation's macroeconomic picture. Other peripheral concepts and issues such as the evolutionary development of industry, the perspectives of the $21^{st}$ century civilization, an analogy between macroeconomics and chemical engineering, and national policies for each macroeconomic entity are also presented in this study.