• Communications of Mathematical Education
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• v.21 no.3
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• pp.407-430
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• 2007

The extreme didactic phenomena that occur by ignoring or overemphasizing the process of personalization/contextualization, depersonalization/decontextualization of mathematical knowledge is always in our teaching practice and in fact, seems to be a kind of phenomena that suppress teachers psychologically or didactically. The study of the problems on error, misconception or obstacles revealed by students has been done continuously, but that of the extreme didactic phenomena revealed by teachers has not. In this study, I will explain four extreme didactic phenomena and help you understand them by giving various examples from several case studies and analyzing them. And also, I will discuss the way to overcome the extreme didactic phenomena in the mathematical class, based on this analysis. This thesis will become a standard of didactic phenomena that are proceeded extremely by having teachers reconsider their own classes and furthemore, will offer the research data for considering better didactic situation.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.2
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• pp.57-66
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• 1988

Sandy dust phenomena was observed from April 19 to 23, 1988 in Seoul and suspended particulate was collected by Andersen air sampler during this period. The samples were analyzed for 16 components $(SO_n^{2-}, NO_3^-, Cl^-, PO_4^{3-}, NH_4^+, F^-, Al, Fe, K, Cu, Mn, Na, Pb, Mg, Ca, Cd)$. The conclusions are as follwes: 1. Total suspended particulate concentation during the period of sandy dust phenomena was 489 $\mug/m^3$ (ordinary times: 140-125 $mug/m^3$) 2. The water - soluble ion component concentration of suspended particulate during the period of sandy dust phenomena was few and the metal concentration of that was more than that of ordinary times. 3. The cumulative frequency distribution of suspended particulates in logarithmic diagram did not show similar to normal log distribution during the period of sandy dust phenomena. 4. $SO_4^{2-}, NO_3^-, Cl^-, and PO_4^{3-}$ was onsided to coarse particle, and $NH_4^+$ and F to fine particle in the size distribution of water - soluble ion components during the period of sandy dust phenomena. 5. Metal concentration was high and Al, Fe, Cu, Mn, Na, Mg, and Ca was onsided to coarse particle, and K, Pb, and Cd to fine particle in the size distribution of metal components. 6. During the period of sandy dust phenomena the quantity of respirable particle (< 1 $\mum$) was about 3 times and that of metal components were about 2 - 11 times than that of ordinary times. 7. The concentrations of $NO_3^-, Cl^-, NH_4^+$ at ordinary times were 1.1 - 4 time than that of the period of sandy dust phenomena.

• Journal of the Daesoon Academy of Sciences
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• v.18
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• pp.149-164
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• 2004

Various social surveys conducted by mass media and government agencies in recent years in Japan suggest that the percentage of those who believe in religion are between twenty and thirty percent. However, more than seventy percent of Japanese visit Shinto shrines or Buddhist temples during the New year period. Although there are varying interpretations on whether Japanese people are religious or not, detailed research shows the existence of certain religious tendencies among Japanese. I base my estimates on research surveys of college students covering a period of almost ten years. It is helpful for understanding the religiosity of the Japanese to differentiate between "clear-cut religion" and "peripheral religious phenomena." The exact boundary between these two categories, however, is difficult to clearly demarcate. "Clear-cut religion" refers here phenomena which are directly related to established religious organizations such as shrine Shinto, Buddhist sects, or Christianity. "Peripheral religious phenomena" covers such phenomena as fortune telling, mystical phenomena, religious customs and similar matters. It is often said that the younger generations are less concerned with religion. Our seven surveys questioning several thousand college students, conducted between 1995 and 2001, show that only between six and seven percent of the students state that they believe in religion. Additionally, the extent of negative attitudes toward religion quite remarkable. On the other hand, students who take part in conventional ritual such as a New year's visit to a shrine or temple and visiting the graves of ancestors amount to about fifty percentage. In spite of the prevailing negative attitude toward religious groups, these students have apparently kept a certain level of interest in religious customs. Moreover, they show a relatively strong interest in fortune telling, mystical phenomena, or supernatural phenomena. The exact degree of a positive attitude toward peripheral religious phenomena differs according to the level of being informed on these matters. As a whole, they largely rely on information gained from their families and local communities. Therefore, we can conclude that there is a degree of transmission of religious culture among younger generations.

• School Mathematics
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• v.1 no.2
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• pp.605-615
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• 1999

In this paper, we explain the pedagogical phenomena appeared in the learning of 0.$\dot{9}$ = 1 in terms of its intrinsic mathematical structure, and investigate the reason why such phenomena happen. Also we analyze such phenomena through the dialogue between student and teacher, and present some instruction idea from the mathematical and educational view points.

• Korean Institute of Interior Design Journal
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• no.16
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• pp.126-134
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• 1998

In Contemporary architecture we could find rough and stiff feeling expression as a special phenomena. This style is combined regionalism to the modern spirit that we could imagine such a phenomena of the modern design toward vernacular culture. it's conception is conformed to the regionalist architecture in that period and the 3rd world experiences, From 1930s resident house Le corbusier introduced vernacular phenomena that considered productional condition of the region and regional environment This tendancy attempted by few young architects. they built building in vernacular phenomena based on the 3rd world experiences and Le Corbusier's architecture. After Le Corbusier's unite d'hbitation in Marseille Ando finishing with diversified material. but Le Corbusier's intention concerned not only to finishing of material but also to practical and human building as he had experienced in vernacular architecture.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.235-236
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• 2002

Tribological phenomena such as wear or transfer are influenced by various factors and have complicated behavior. Therefore, it is difficult to predict the behavior of the gribological phenomena because of their complexity. But, those tribological phenomena can be considered simply as to transfer micro material particles from the sliding interface. Then, we proposed the numerical simulation method for tribological phenomena such as wear of transfer using stochastic process models. This numerical simulation shows the change of the 3-D surface topography. In this numerical simulation, initial 3-D surface toughness data are generated by the method of non-causal 2-D AR (autoregressive) model. Processes of wear and transfer for some generated initial 3-D surface data are simulated. Simulation results show successfully the change of the 3-D surface topography.

• Journal of Korean Elementary Science Education
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• v.27 no.4
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• pp.371-384
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• 2008

The purposes of this study were to investigate perspective teachers' conceptions of liquid-state and get implications for the direction of science curriculum or professional development. The instrument was composed of seven questions focusing on aspects of liquid-state phenomena. The results showed that the participants have various alternative concepts about liquid-state. The problem revealed in almost every question was their macroscopic explanations for the phenomena. In addition, it appeared that the participants seemed to understand phenomena in terminology level, but they didn't know basic reasons or fundamental concepts about the phenomena. It is required to change the curriculum or instructional methods in secondary school and teacher education programs to anchor the scientific concepts on molecular or microscopic level.

• Journal of KSNVE
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• v.6 no.4
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• pp.439-446
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• 1996

This paper introduces a newly designed pendulum system that enables the more accurate boservation of dynamic behaviour arising from both horizontal and vertical(i.e. two dimension) excitation. First, experiments were carried out to examine the frequency responses of the devised pendulum system. Interestingly, experimental results for the three excitation angles of 22, 32 and 48 degree show 'new' jump phenomena. For the further understanding of these phenomena, experimental investigationhas been made to identify the equation of motion of the pendulum system from experimental data. This attempt has revealed that the viscous, coulomb and aerodynamic damping factors are involved in the equation of motion. By applying the Ritz averaging method to the equation, it becomes apparent that the jumping phenomena of the pendulum system in this work is more theoretically understood.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1704-1709
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• 2000

This paper proposes a spherical probe allowing acoustic intensity measurements in three dimensions to be made, which creates a diffracted field that is well-defined, thanks to analytic solution of diffraction phenomena. Six microphones are distributed on the surface of the sphere along three rectangular axes. Its measurement technique is not based on finite difference approximation, as is the case for the ID probe but on the analytic solution of diffraction phenomena. In fact, the success of sound source identification depends on the inverse models used to estimate inverse diffraction phenomena, which has non-linear properties. In this paper, we introduce the concept of nonlinear inverse diffraction modeling using a neural network and the idea of 3 dimensional sound source identification with several tests.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.18 no.2
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• pp.144-153
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• 2009

It is widely known that no-slip assumptions are often violated on regular basis in micrometer- or nanometer-scale fluid flow. In the case of cavity-filling process of nanoimprint lithography(NIL), slip phenomena take place naturally at the solid-to-liquid boundaries, that is, at the mold-to-polymer or polymer-to-substrate boundaries. If the slip or partial slip phenomena are promoted at the boundaries, the processing time of NIL, especially of thermal-NIL which consumes more tact time than that of UV-NIL, can be significantly improved. In this paper it is aimed to elucidate how the cavity-filling process of NIL can be influenced by the slip phenomena at boundaries and to what degree those phenomena increase the process rate. To do so, computational fluid dynamics(CFD) analysis of cavity filling process has been carried out. Also, the effect of mold pattern shape and initial thickness of polymer resist were considered in the analysis, as well.