Korean Journal of Construction Engineering and Management
/
v.9
no.1
/
pp.187-198
/
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.
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
/
v.58
no.4
/
pp.393-405
/
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.
Lee, Moo Seok;Lee, Jong Kyu;Nam, Ji Ho;Ha, Tae Yeong;Lim, Yeong Hyeon;Kil, Sang Hyeong
Journal of Life Science
/
v.27
no.6
/
pp.708-725
/
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.
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.
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
/
v.43
no.5
/
pp.451-458
/
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.
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.
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.
Kim, Eun-Ju;Lee, Sang-Bub;Yoon, Ill-Hee;Lee, Hyo-Nyong
Journal of the Korean earth science society
/
v.30
no.6
/
pp.787-798
/
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.
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.
Journal of The Korean Association For Science Education
/
v.37
no.4
/
pp.539-552
/
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.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.