• Journal of Educational Research in Mathematics
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• v.13 no.4
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• pp.485-493
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• 2003

The purpose of this study is to suggest the alternative strategies for teaching mensuration of parallelogram raised by Max Wertheimer, a gestalt psychologist who was particularly concerned with mathematics learning and teaching. For this, 77 student teachers were paper and pencil tested and we could get the 7 interesting and useful ideas from their datas in spite of the fact that not many student teachers correctly responsed. Analysing the datas, it turned out all the 7 ideas are related to equivalent transformation and can make children more easily to see the structure of area of Wertheimer's parallelogram than traditional approach.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.55-60
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• 2000

Wire codes, introduced by Wertheimer and Leeper, are interesting largely because several case-control studies have reported associations between them and certain types of cancers, including childhood leukemia. This paper is concerned with the reliability of wire codes as a surrogate for residential electric and magnetic field, divided into four categories based on the electrical wiring within 40m of homes. To examine the correlation between spot measurements and wire codes, EMF was measured by using HI-3604 and classified by wire codes. The correlation between long-transformed RMS of magnetic field and wire codes was 0.81. But the correlation between log-transformed RMS of electric field and wire codes was 0.27. The results led us to determine a four category from of the Wertheimer and Leeper code that 1) may be useful in domestic epidemiological studies and 2) is not suitable for electric field exposure. Thus, the critical point of exposure assessment in residential magnetic field is to classify a wire code precisely.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.331_332
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• 2009

1979년 Nancy Wertheimer와 Ed Leeper가 수행한 연구결과에서 자기장이 소아백혈병에 의한 사망률을 높일 수 있다는 가능성을 발표한 이후, 인체건강에 유해한지에 대한 많은 궁금증이 증가해 왔다. 이후 일부 검증되지 않은 연구결과를 여과없이 인용 보도함으로써 대다수 국민이 오해하고 막연한 불안감을 갖게 된 측면이 있으며, 전기의 소중함은 누구나 인정하면서 전력시설 인근 주민은 자계에 대해 염려하며 건설반대, 전력설비 이전 등 극저주파전자계의 피해를 우려하고 있는 실정이다. 본 고에서는 국내 송전선로 극저주파자계의 노출현황을 살펴보고, 2007년 6월 세계보건기구(WHO)가 발표한 극저주파전자계와 인체건강의 관계 검토를 마무리한 공식보고서(Fact sheet No.322)를 고찰하고자 한다.

• Korean Association for Visual Culture
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• v.19
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• pp.189-221
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• 2012

This thesis investigates the development of optical instruments in the 19th century, before the birth of the cinema, and the principle of the perception of moving images. For this purpose it traces the development stages of the optical instruments which demonstrated 'illusion of movement' from 1820s when the 'persistence of vision' had begun to be researched by scientists. Then, it examines the theory of the 'persistence of vision' or 'afterimage effect' known as the principle in the perception of illusion of movement produced from moving images. The optical instruments in the 19th century that presented the illusion of movement began with the Thaumatrope (double-sided picture disc), and appeared from the Phenakistiscope/Stroboscope (revolving disc), the Zoetrope (revolving drum) and the Praxinoscope (mirror-reflexive revolving drum), and in 1892 the Projection-Praxinoscope presented firstly the moving pictures (animation) on the screen. According to the research of psychology and physiology in the early 20th century it has been recognized that the 'afterimage effect' theory is not sufficient to explain the perception of illusion of movement from the moving images which is closely related to the particularity of the visual perception system of the human eyes. Since then, the Phi-phenomenon suggested 1912 by the Gestalt psychologist, Max Wertheimer (1880-1943), is regarded as the most persuasive theory until now, although it is still imperfect.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.10
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• pp.485-491
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• 2002

Since Wertheimer and Leeper reported possible adverse health effects of magnetic field in 1979, worldwide researches on this issue have been conducted. More recently, the U.S. Congress instructed the NIEHS (National Institute of Environmental Health Sciences), NIH (National Institute of Health) and DOE (Department of Energy) to direct and manage EMF RAPID (Electric and Magnetic Fields Research and Public Information Dissemination) program aimed at providing scientific evidence to clarify the potential for health risks from exposure to extremely low frequency electric and magnetic fields(ELF-EMF). Although they concluded that the scientific evidence suggesting adverse health risks of ELF-EMF is weak, the exposure to ELF-EMF cannot be recognized as entirely safe. Therefore, the purpose of this article is to describe magnetic field 3-D calculation and to evluate eddy current of human body compare to international guide line recognized one of the basic problems. In open boundary problem, Magnetic field using FEM is not advantageous in the point of the division of area and the proposition of the fictitious boundary. Therefore, we induced the analytic equation of magnetic field calculations so but the finite line segment based on Biot-Savarts law Also, Eddy currents induced due to ELF-EMF magnetic field are computed. To calculate induced currents, impedance method is used in this paper, An example model of human head with resolution of 1.27cm is used. In this paper, We evaluate the magnetic field and eddy current of human head around 765 kV transmission lines compare to international guide line.