• Journal of The Korean Association For Science Education
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• v.19 no.1
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• pp.78-90
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• 1999

This study investigated the high school students' and science teachers' understanding of idealization involved in the physics experiment. Major research questions are as follows: (1) what kind of ideal conditions do subjects identify from the presented experimental context? (2) do subjects think how well ideal conditions are satisfied with the experiment? (3) how well do subjects expect the effect of idealization on the experimental result? (3) what kind of view point do science teachers have about the ideal condition involved in the experiment? A total of 85 subjects were given 6 questions related with the research questions I. 2. and 3. with simple experiment about the brightness of the bulbs connected with parallel to the battery. And another 4 questions for the forth research question were given to 42 science teachers. Subjects' responses were summarized and used to draw the implications for the teaching of physics experiment.

• Atmosphere
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• v.31 no.4
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• pp.445-459
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• 2021

This study uses a cloud-resolving storm simulator (CReSS) to understand the individual effect of determinant meteorological factors on snowfall characteristics in the Yeongdong region based on the rawinsonde soundings for two snowfall cases that occurred on 23 February (Episode 1) and 13 December (Episode 2) 2016; one has a single-layered cloud and the other has two-layered cloud structure. The observed cloud and precipitation (snow crystal) features were well represented by a CReSS model. The first ideal experiment with a decrease in low-level temperature for Episode 1 indicates that total precipitation amount was decreased by 19% (26~27% in graupel and 53~67% in snow) compared with the control experiment. In the ideal experiment that the upper-level wind direction was changed from westerly to easterly, although total precipitation was decreased for Episode 1, precipitation was intensified over the southwestern side (specifically in terrain experiment) of the sounding point (128.855°E, 37.805°N). In contrast, the precipitation for Episode 2 was increased by 2.3 times greater than the control experiment under terrain condition. The experimental results imply that the low-level temperature and upper-level dynamics could change the location and characteristics of precipitation in the Yeongdong region. However, the difference in precipitation between the single-layered experiment and control (two-layered) experiment for Episode 2 was negligible to attribute it to the effect of upper-level cloud. The current results could be used for the development of guidance of snowfall forecast in this region.

• Journal of Technologic Dentistry
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• v.2 no.1
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• pp.11-15
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• 1980

This study was aimed at obtaining an ideal gold alloy for dental prothetic. The experiment was on physical characteristics of gold alloy and mixing proportion for proper appliance to living tissues. The most frequently used material in the past for dental prothetic was gold, but recently used are mictures or precious metals and non-precious, which are proved to affect on oral tissues. The experiment was to examine gold alloy over its physical and chemical qualities and to make an ideal type of gold alloy by means of statistic and laboratory research.

• Journal of Korean Elementary Science Education
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• v.23 no.4
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• pp.318-325
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• 2004

The purpose of this study is to improve the experiment of dihydrogen production which was newly added to the 7th curriculum of the elementary science education. For this study, the teachers who had taught 6th grade students were asked about the difficulties they ever had in the dihydrogen production experiment by questionnaire. And the contents of the science textbook and teachers' guide book were analyzed. According to this investigation, the following controversial points were found. First, they didn't have exact explanations about the concentration of hydrochloric acid and the quantity of hydrochloric acid and magnesium in the science textbook and teachers' guide book. Second, the experiment which can show well the nature of dihydrogen was not included because of the safety problem. So this paper presents the ideal condition for the production of dihydrogen and an experimental method to show the nature of dihydrogen. The most ideal condition of dihydrogen production includes 40 mL of 2 molarity hydrochloric acid and 1 g of magnesium. It took 5' 42＆apos; on average to gather two bottles (250 mL) of dihydrogen. In this condition it was possible to reduce the risk of accidents and to economize the materials. This paper proposes the experiment of dihydrogen explosion with a test tube and a film box which is not included in the 7th scince textbook. If teachers show the experiment of dihydrogen explosion with a test tube or film box to students at a class, it will be more interesting for students. And they will be able to help students to understand that dihydrogen can be gathered.

• Journal of The Korean Association For Science Education
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• v.19 no.1
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• pp.62-77
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• 1999

Idealization has an important role in the process of learning as well as in physics research. The purpose of this study was to survey students' and science teachers' recognition of the ideal conditions involved in the process of problem solving and of explaining the natural phenomena. The instrument for probing the understanding of the ideal conditions in the domains of force, electricity and heat was administered to general high and science high school students and science teachers. The framework of responses composed of three categories. The first category is "idealized conditions relevant to problem", the second "not relevant idealized conditions", which has more delicate subcategories of general/ irrelevant conditions, simple statement of formula/ law, repeating problems, uncorrect explaining/ describing conditions, and the last "no responses". The results of analysis showed that the majority of the subjects well understood the various ideal conditions, especially for science high school students. But some of them could not differentiate the ideal condition from the general conditions, or they simply repeat the problem situation or the formula. The understanding of idealization is different by the domains of physics. We discovered that the misconceptions about the ideal conditions in various physical phenomena and revealed some interconnection of researches in the fields of misconception and the ideal condition.

• Journal of Korean Physical Therapy Science
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• v.3 no.4
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• pp.113-120
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• 1996

The purpose of this study was to comparison clinical applied versus theoretical fitness on axillary crutch in human stance phase. Ideal crutch length is defined as the length of the crutch, including accessories, obtained during stance when the crutch tip is 15 cm(about 6inch) lateral and 15 cm(about 6 inch) anterior to the fifth toe and the axillary pad is 5 cm(about 2 inch) below the axillay fold. The participations(volunteers) were 71 inpatients(53 men and 18 women) who have orthopedic and neurological impairment on unilateral and/or bilateral lower extrimities, and mean age was 31.4 year old. Prior to participation, each subject informed the procedures of experiment from researcher and assistant researcher. This measured for axillary crutch using each of the following aspects : (1) length of actual using crutch, (2) length of axillary fold after modified(77% of actual height), (3) angle of elbow flexion after modified(77% of actual height). In order to determine the statistical significance of result, t-test were applied at the 0.05 level of significance. The result were as follows ; 1. There was significant difference between actual crutch and ideal crutch length(77% of actual height)(p<0.05). 2. There was significant difference of length of axillary fold between actual and ideal crutch (77% of actual height)(p<0.05). 3. There was significant difference of angle of elbow flexion between actual and ideal crutch(77% of actual height)(p<0.05).

• Journal of the Korean housing association
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• v.27 no.5
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• pp.37-44
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• 2016

The purpose of this study is to investigate the relationship of architectural ideology and characteristics of spatial composition between Moisei Ginzburg's Narkomfin communal house and Le Corbusier's Unite d'Habitation. Narkomfin communal house and Unite d'Habitation is considered as example of experiment to construct ideal community housing model. Moisei Ginzburg designed Narkomfin communal house to make typical housing model for socialist city. Meanwhile, Le Corbusier is considered as a leader of modern functionalism architecture. His Unite d'Habitation in Marseille is important experiment for housing model in modern period. Unite d'Habitation is known to be affected by Narkomfin communal house in terms of architectural ideology and its spatial composition. This study focuses on comparative analysis between Narkomfin communal house and Unite d'Habitation through drawings, pictures and various literatures. Narkomfin communal house and Unite d'Habitation have common ideology to realize ideal community housing model. Moreover, both of them have considerable similarities in their spatial composition. First of all, unit housing of Narkomfin and Unite d'Habitation are maisonette type. Secondly, both of them have unique system that one corridor serve two of housing unit. Also, both have common facility such as laundry, childcare which is connected with their housing.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.475-490
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• 1993

Even though modem ideal body type is rather tall and slim one, most of women don't coincide with it exactly. The objective of this research was to study the optical illusion effect of clothing design line so that average Korean women can approach the modern ideal body type. This research also tried to show the more scientific method to make stimulus by computer simulation and to present quantitative data. For the experiment, 9 design variables were selected from design principal book as follows : waistline level, skirt length, horizontal line emphasis, vertical line emphasis. princess line, vertical stripe, horizontal stripe, diagonal stripe. Each variable was divided into 4 levels so that 36 experimental designs were made. Visual stimuli which same model was wearing each design were recreated by the CAD system. These were given to evaluating panels through slide projecter. Then panels compared experimental design with basic design by 'tall effect' and 'slim effect', All the data from the experiment were analyszed by ANOVA and DUNCAN test for multiple comparison to study significance, direction(positive or negative), degree, proper extent of optical illusion effect. The result showed that some designs have optical illusion effect to make better look. In addition, it proved that the stronger design variable does not mean the more optical illusion effect and there was proper extent which produce the best illusion effect in each design variable.

• Journal of Engineering Education Research
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• v.23 no.3
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• pp.32-40
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• 2020

A new moment of inertia experiment apparatus different from the existing one has been developed, which does not require deformation of a sample in order to fix it to the apparatus. This new experiment apparatus was able to experiment with constant-shaped objects that did not deform the samples, so that it enabled them for conducting an experiment which is close to an ideal rigid model dealt in the general physics course. The new experimental apparatus was easy and accurate in measuring the physical quantity by using the experimental principle of physical pendulum. In the results of the measurement of the moments of inertia of the six samples, all measurements were made to be accurate enough to measure with very small errors within 1%. In addition, it has been found to be useful as an experiment apparatus to understand the concept of the moment of inertia and to prove the formula for moment of inertia. Therefore, if the new moment of inertia experiment apparatus developed in this study is used in students' experiments, it is expected that students will be able to greatly increase their understanding of the concept of moment of inertia.

• Journal of Korean Elementary Science Education
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• v.23 no.2
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• pp.152-158
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• 2004

The purpose of this study was to find the difficulties and problems in the carbon dioxide production experiment and to suggest the device for the improvement. Many students have misconception for the smell of carbon dioxide. I found that the smell of carbon dioxide of producting through the experiment didn't concern with the quantity of calcium carbonate. I certificated that the smell of carbon dioxide was related with the concentration of hydrochloric acid. I built two trap applicaing suction in the gas production device to exclude fully the smell of carbon dioxide. So the smell of carbon dioxide was not present by passing the two trap. To find the ideal experimental conditions I perform the experiment step by step. As the result enough carbon dioxide to use for the property experiment was collected under the condition that is 60 mL of 3 molarity hydrochloric acid and 30 g calcium carbonate. I certificated to mesuring flowing quantity of carbon dioxide using the flow meter of carbon dioxide. In the improvement experiment of the property of carbon dioxide, I proposed the experiment device regarding as spreading of the gas and children's interest. To improve the problem of gas production experiment, I proposed the gas certification device using a thread.