• Title/Summary/Keyword: physics concept

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Inventory Management in Construction Operations Involving on-site Fabrication of Raw Materials (원자재 조립.가공과정을 갖는 건설공사 프로세스의 적정 재고관리 방안에 관한 연구)

  • Im, Keon-Soon;Han, Seung-Heon;Jung, Do-Young;Ryu, Chung-Kyu;Choi, Seok-Jin
    • Korean Journal of Construction Engineering and Management
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    • v.9 no.1
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    • pp.187-198
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    • 2008
  • There are usually plenty of material inventories in a construction site. More inventories can meet unexpected demands, and also they may have an economical advantage by avoiding a probable escalation of raw material costs. On the other hand, these inventories also cause negative aspects to increase costs for storing redundant inventory as well as decreasing construction productivity. Therefore, a proper method of deciding an optimal level of material inventories while considering dynamic variations of resources under uncertainty is very crucial for the economical efficiency of construction projects. This research presents a stochastic modelling method for construction operations, particularly targeting a work process involving on-site fabrication of raw materials like iron-rebar process (delivery, cut and assembly, and placement). To develop the model, we apply the concept of factory physics to depict the overall components of a system. Then, an optimal inventory management model is devised to support purchase decisions where users can make timely actions on how much to order and when to buy raw materials. Also, optimal time lag, which minimizes the storage time for pre-assembled materials, is obtained. To verify this method, a real case is applied to elicit an optimal amount of inventory and time lag. It is found that average values as well as variability of inventory level decreased significantly so as to minimize economic costs related to inventory management under uncertain project condition.

Characteristics of Social Interaction in Scientific Modeling Instruction on Combustion in Middle School (연소의 과학적 모형형성 수업에서 나타난 중학생의 사회적 상호작용 특징)

  • Park, HyunJu;Kim, HyeYeong;Jang, Shinho;Shim, Youngsook;Kim, Chan-Jong;Kim, Heui-Baik;Yoo, Junehee;Choe, Seung-Urn;Park, Kyung-Mee
    • Journal of the Korean Chemical Society
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    • v.58 no.4
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    • pp.393-405
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    • 2014
  • The purpose of this study was to investigate the characteristics of social interaction on cultural aspects, verbal interaction, and discussion maps in scientific modeling instruction on combustion in middle school. Revised-CLEQ (Cultural Learning Environment Questionnaire), verbal interaction framework, discussion maps analysis were implemented for this study. The results of study follow respectively. First, the characteristics on cultural aspects of middle school students showed cooperation rather than competition in terms of collectivism. Students' attitudes to learning science tended to depend on others' idea, and students were passive and reluctant to present their comments when they were modeling work. Second, for the characteristics of verbal interaction, they simply presented knowledge related to build a model. The response to comments and feedback was relatively few. Third, discussion maps showed a lot of interaction for reponses that was alternatively brought the concept of commenters, which students were depended on a specific one, and responses. There were not many interaction for elaboration, which were described to have new presented ideas, corrections, and reasons when they exchange their ideas. In this study the model type of interaction affecting the formation of the students understanding of and in our country, it makes a lot of social interactions as the basis for teaching system could be utilized.

The Effect of Ionizing Radiation on the Ultrastructural Changes and Mechanism on the Cytoplasmic Organelles (전리방사선이 세포질 소기관의 미세구조변화와 기전에 미치는 영향)

  • Lee, Moo Seok;Lee, Jong Kyu;Nam, Ji Ho;Ha, Tae Yeong;Lim, Yeong Hyeon;Kil, Sang Hyeong
    • Journal of Life Science
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    • v.27 no.6
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    • pp.708-725
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    • 2017
  • Ionizing radiation is enough energy to interact with matter to remove orbital electrons, neutrons, and protons in the atom. Ionizing radiation like this leads to oxidizing metabolism that alter molecular structure through direct and indirect interactions of radiation with the deoxyribonucleic acid in the nucleus and cytoplasmic organelles or via products of cytoplasm radiolysis. These ionization can result in tissue damage and disruption of cellular function at the molecular level. Consequently, ionizing radiation-induced modifications of ion channels and transporters have been reported. When the harmful effects exceed those of homeostatic biochemical processes, induced biological changes persist and may be propagated to progeny cells. Also, Reactive oxygen species formed on the effect of ionizing radiation can get across into neighboring cells through the cell junctions that are responsible for intercellular chemical communication, and may there bring about changes characteristic to radiation damage. Depending on radiation dose, dose-rate and quality, these protective mechanisms may or may not be sufficient to cope with the stress. This paper briefly reviewed reports on ionization radiation effects on cellular level that support the concept of radiation biology. A better understanding of the biological effects of ionizing radiation will lead to better use of and better protection from radiation.

Case Studies Via Level Classes Of The Convergence Program For Verifying The Center Of Gravity (무게중심 확인 융합 프로그램의 수준별 수업 적용 사례연구)

  • Kim, Su Geum;Ryu, Shi Kyu;Kim, Sun Bae
    • Journal of the Korean School Mathematics Society
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    • v.17 no.4
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    • pp.771-804
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    • 2014
  • The concept of the center of gravity is presently being introduced in elementary school curriculums and is broadly applied to Mathematics, Physics, and the Engineering field in University education which are mostly theoretical classes much separated from actual life in the practical educational field. In 2013, ${\bigcirc}{\bigcirc}$ University of Science and Gifted Education, had developed the multidisciplinary approach program of verifying the center of gravity for gifted students, but this program was reconstructed and applied to ordinary students and the effectiveness was analyzed to lay the foundation and generalize this convergence education. Including experiments for verifying the center of gravity in an object with a hollow interior and the existence of a center of gravity outside an object, I proposed realizing the calculations by considering the weight of the lever, the Principle of the lever being a core factor when finding the center of gravity. We altered the existing 8 step program to a 4 step program for the told 65 students from elementary, Junior and High School students, letting them freely select the class lecture by themselves. The analysis attained from surveys, debates and interviews showed that by precise error analysis, students achieved a higher success experience, showing us the importance of the development of a new convergence program.

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Development of Quantification Method for Bioluminescence Imaging (발광영상에 대한 정량화 방법 개발)

  • Kim, Hyeon-Sik;Choi, Eun-Seo;Tak, Yoon-O;Choi, Heung-Kook;Lee, Ju-Young;Min, Jung-Joon;Lee, Byeong-Il
    • Nuclear Medicine and Molecular Imaging
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    • v.43 no.5
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    • pp.451-458
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    • 2009
  • Purpose: Optical molecular luminescence imaging is widely used for detection and imaging of bio-photons emitted by luminescent luciferase activation. The measured photons in this method provide the degree of molecular alteration or cell numbers with the advantage of high signal-to-noise ratio. To extract useful information from the measured results, the analysis based on a proper quantification method is necessary. In this research, we propose a quantification method presenting linear response of measured light signal to measurement time. Materials and Methods: We detected the luminescence signal by using lab-made optical imaging equipment of animal light imaging system (ALIS) and different two kinds of light sources. One is three bacterial light-emitting sources containing different number of bacteria. The other is three different non-bacterial light sources emitting very weak light. By using the concept of the candela and the flux, we could derive simplified linear quantification formula. After experimentally measuring light intensity, the data was processed with the proposed quantification function. Results: We could obtain linear response of photon counts to measurement time by applying the pre-determined quantification function. The ratio of the re-calculated photon counts and measurement time present a constant value although different light source was applied. Conclusion: The quantification function for linear response could be applicable to the standard quantification process. The proposed method could be used for the exact quantitative analysis in various light imaging equipments with presenting linear response behavior of constant light emitting sources to measurement time.

Suggestions for an Effective Earthquake R&D Strategy in Korea through an Analysis of Japan's Earthquake Disaster Prevention System (일본의 지진방재·대응 시스템 분석을 통한 효과적인 우리나라 지진 R&D 전략 제언)

  • Kim, Seong-Yong;Lee, Jae-Wook
    • Economic and Environmental Geology
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    • v.53 no.3
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    • pp.321-336
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    • 2020
  • The Headquarters for Earthquake Research Promotion (HERP) represents the upper-most level of Japan's earthquake disaster prevention governance. Its policy committee establishes the national earthquake investigation research promotion plan. The earthquake investigation committee of HERP collects survey geo-data and evaluates the research results of each earthquake disaster prevention agency. The establishment of an earthquake-related geo-resilience research strategy is both necessary and desirable for Korea. The concept of geo-resilience entails the ability to improve disaster resilience through the application of research results and the convergence of geoscience with science and technology (S&T) including the humanities and social sciences. The achievement of geo-resilience requires a national long-term roadmap and strategy for earthquake prediction research, the development of earthquake disaster prediction and prevention technology, Geo-ICT convergence technology development, implementation of a geocyber physics system (Geo-CPS), the use of geo-mimetics, and geoscientific R&D as it relates to local communities. Through such efforts, the national research institutes of Korea will be able to develop earthquake prediction capacities in relevant fields, reinforce proactive response capabilities, enhance community-level confidence in geodata and its research results, foster next-generation geoscientific manpower, and expand geoscientific infrastructure.

Understanding the Selective Attention and Animation Induction Device According to the Visual Capture of Audience (관객의 시각포획현상에 따른 선택적 주의집중과 애니메이션 유도장치의 이해)

  • Lee, Jong-Han
    • Cartoon and Animation Studies
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    • s.41
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    • pp.133-152
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    • 2015
  • Some artists and scientists in physics and animation originating from research on its form of expression thanks to the rapid development of the example in the late 20th century image production technology integrating existing media feature, perform a re-creation and pop culture content has been recognized as a key factor. animation of the modern emphasis is also commercial and artistic activities as show whether the artist can not be excluded that also target audience. The audience does not want only to receive offers simply 'seeing' and 'hearing' in the animation requires a more indirect mental met. the other side, the director should lead the audience to immerse myself in work as intended mystification induce the world. where a conflict occurs between the audience and the director and The director needs to have its troubleshooting point to 'Technology of the communication'. Which is reduced to 'How will tell,' is technology communication technologies that are abbreviated representations of animation director is accessible to the audience and it is a close relationship between the psychological aspect of audience. Because, the audience is reproduced in a limited space, but he called on the board of directors and the same time the screen, the audience located at reception and the director located at provide. It is given. led force is given to the director. for this reason, The director needs to pay attention to the psychological aspect of audience this can be explained based on psychoanalytic theory. In this paper, "How can you lie to the audience and the director is the same line?" put down logic that is the animation audience under the logic that takes place visually capture phenomenon "selective attention" and sub-concept of "goal-directed selection' and 'stimulus-driven capturel' for theory of psychology. also, Induction device to elicit selective attention of the audience accordingly, let's consider whether and how they apply in animation.

Development of Experimental Apparatus to Efficiently Educate the Phenomena by Coriolis Force (전향력에 의한 현상을 효과적으로 교육시킬 수 있는 실험 장치의 개발)

  • Kim, Eun-Ju;Lee, Sang-Bub;Yoon, Ill-Hee;Lee, Hyo-Nyong
    • Journal of the Korean earth science society
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    • v.30 no.6
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    • pp.787-798
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    • 2009
  • A new apparatus was presented in order to help understand the concept of the Coriolis force which is essential in understanding the trajectories of the atmospheric current and the tide of seawater. In the apparatus proposed in high-school textbooks, since the slide from which the ball is released is set outside the rotating disk, it was not possible to interpret, with the trajectory of the ball on the disk, the motion of the atmosphere and the current of seawater occurring as a result of the Coriolis force. In order to resolve such problem, a new apparatus was developed in which the slide was set on the disk and rotated with the disk. Experiments were carried out using both the existing apparatus and the new apparatus, and the results were compared. While, in the experiment performed with the existing apparatus, it was difficult to analyze the trajectory of ball because the motion of the ball was not smooth when it hit the disk, in the experiment with the new apparatus it was much easier to analyze the trajectories. It was also possible to compare the trajectories when the initial velocity of the ball was varied.

Change of Science Teachers' Perceptions About the Atmosphere Composition of Molecules with Different Masses (서로 다른 질량을 가진 분자들로 이루어진 대기의 조성에 대한 과학교사들의 인식 변화)

  • Yoo, Seunggyun;Paik, Seoung-Hey
    • Journal of the Korean Chemical Society
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    • v.62 no.4
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    • pp.288-298
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    • 2018
  • In this study, we surveyed pre- and post-perceptions of fourteen science teachers related to the atmosphere composition of molecules with different masses by the developed test. As a result of the test, the teachers were classified into two types of thoughts; One of them is considered the atmosphere to be a homogeneous solution, and the other is a thought that the composition ratio of the atmosphere was not homogeneous considering the different weights of particles. The two types were reclassified into three categories; one of them is considering large gravity effect, another is considering small gravity effect, and the other is considering medium scale gravity effect. Total six types of thoughts were found from the pre-test. After introducing crosscutting concepts which are related to the composition of atmosphere. The teachers discussed the phenomena with the molecular motion by weights of atoms and temperature, the homogeneity of the solution of air in chemistry domain. They also discussed with the relationship between mass and gravity and distance in physics domain. And the discussion included distribution of the atmosphere, convection phenomena, etc. After the discussion, the teachers changed their pre-conceptions to post-concoctions considering combined perspectives of gravity, mass, temperature, altitude etc. Through these changes, we are able to confirm the importance of crosscutting concepts covered in various disciplines. In the integrated science, we should help teachers to provide students with these types of thinking in order to form a coherent world-view and to carry out inquiry thinking as an intellectual tool.

Analysis of Trends of Model and Modeling-Related Research in Science Education in Korea (과학교육에서 모델과 모델링 관련 국내 과학 교육 연구 동향 분석)

  • Cho, Hye Sook;Nam, Jeonghee
    • Journal of The Korean Association For Science Education
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    • v.37 no.4
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    • pp.539-552
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    • 2017
  • The purpose of this study is to investigate the trends of model and modeling-related research in science education from 1989 to 2016 in Korea. Eighty-five (85) models and modeling-related journal articles were extracted from the KCI-listed journals and analyzed according to the criteria such as participants, research fields, research design, methods, data collection and elements of metamodeling knowledge. According to research participants, three out of four (3/4) were studied for students and the rest were for teachers. More than half of the studies for students were conducted with middle and high school students. The research fields of models and modeling-related researches in science education were comprised of earth science, chemistry, biology science, physics and science course. With regards to research design, the highest type is qualitative research and followed by hybrid research and quantitative research. According to research methods, the most numerous researches that were analyzed was the effectiveness of program, which was a developed model and modeling-related research. The analysis from the elements of the metamodeling knowledge showed most of model and modeling-related research utilized for the change of scientific concept or understanding.