• Title/Summary/Keyword: Thought Experiment

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Reasoning-Based Inquriy Model Embedded in Earth Science Phenomena (지구과학적 현상의 특성을 고려한 추론 중심 탐구수업 모형 제안)

  • Lee, Gyu-Ho;Kwon, Byung-Doo
    • Journal of the Korean earth science society
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    • v.31 no.2
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    • pp.185-204
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    • 2010
  • Inquiring earth science phenomena is characterized by the followings: a big scale of time and space, inaccessibility, uncontrollability, and complexity. Thus, it is very difficult or, in some cases, impossible to investigate them through the actual manipulation in laboratories. Therefore, it is necessary to provide chance for students to experience scientific inquiry without actual manipulation in earth science classes. This study is to explore the role of reasoning based on a thought experiment as a representative model without actual manipulation, and to investigate features of various inquiry models using reasoning in classes. We can make implications when applying for applying each inquiry model to earth science classes, proposing a reasoning-based inquiry model embedded in earth scientific phenomena.

Development of chemical conversion coating process for Mg-Al alloy and its anti-corrosion property (마그네슘-알루미늄 합금의 화성처리 공정 개발과 그 내식성 평가)

  • Kim, Seong-Jong
    • Proceedings of the Korean Society of Marine Engineers Conference
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    • 2006.06a
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    • pp.265-266
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    • 2006
  • The chemical conversion coating formed on magnesium alloy investigated for low cost and harmless in environment by using the colloidal silica as the main component. The film formed in 298 K is thick, the film, which was thought combination of Si-O, was formed. The film formed in 313 K is thinner than that in 298 K. The quantity of film formed at high temperature such as 333 K and 353 K is smaller than dissolved quantity. At the anodic polarization experiment, corrosion resistance in sealing by hot water after chemical conversion treatment in basic solution condition get worse than that in comparison with basic solution condition. In salt spray test, the ratio of black rust on specimen that did not conducted chemical conversion treatment was five times or more compared with those of chemical conversion treated specimen. The film thickness of chemical conversion coating produced by alkali treatment process is thinner than in comparison with that of specimen produced in basic chemical conversion treatment solution condition. It is thought, however, that it showed good corrosion resistance during salt spray test because the area of microcracks is small.

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A thought experiment on the Cochlodinium bloom in Korean waters (한국해역 Cochlodinium의 이상증식에 대한사고실험)

  • 이동섭
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.9 no.4
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    • pp.173-178
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    • 2004
  • Chronic Cochlodinium blooms in the southern waters of Korea have brought about considerable economic losses for about a decade, This paper aims to reframe current perspectives on the outbreak mechanism and the remediation schemes through a thought experiment in a context of mass balance and mathematical ecology. Far different explanations emerge from a careful examination of the scientifically unnoticed clues and a through discussion on the phytoplankton conservation equation. Logic of the eutrophication-induced red tide subjects to criticism. It is strongly recommended that the current remediation scheme to exterminate the target species should be rerouted to an environmentally sound competition enhancement tactics. Finally a novel convergence-float-aggregation hypothesis is proposed as an outbreak mechanism.

Effect of Reclaimed Sewage Irrigation on Paddy Rice Culture and Soil Characteristics (오수처리수의 관개가 벼 생육 및 토양 특성에 미치는 효과)

  • 윤춘경
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.3
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    • pp.66-75
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    • 2000
  • Effect of reclaimed sewage on the paddy rice culture was examined by field experiment for two consecutive years. The domestic sewage was treated by the constructed wetland and the effluent of the treatment wetland was used for irrigation water. The reclaimed sewage was diluted before irrigation in the first year and it was used without dilution in the second year experiment. Growth components and yields were compared against the control plot where conventional method was applied. And also soil characteristics of the plots before and after reclaimed sewage irrigation were analyzed Generally addition of the reclaimed sewage irrigation didn't affect paddy rice culture adversely and even enhancement was observed. Fertilization was thought to be important factor for rice culture rather than irrigation water quality. Conventional fertilization and reclaimed sewage irrigation which contained high nutrient concentration resulted in better growth and more yield. Unlike widespread concern lodging did not happen even in the case of irrigation with average 90mg/L of T-N and conventional fertilization. Soil characteristics changed after irrigation and significant EC increasing was observed for the reclaimed sewage irrigation plots. From soil analyses salt accumulation could be a more potential problem than nutrients like nitrogen and phosphorus in the use of reclaimed sewage irrigation. Overall reclaimed sewage irrigation was thought to be one of practical alternatives for the ultimate disposal of sewage in rural area.

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A study on the understanding of limitations of experiential viewpoints for 9th grade students (증명에서 경험적 관점의 한계에 대한 중학교 3학년 학생들의 이해 연구)

  • Rho, Eun Hwan;Kang, Jeong Gi
    • The Mathematical Education
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    • v.54 no.1
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    • pp.13-30
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    • 2015
  • The mathematical object is conceptual. Thus we can not prove the property of mathematical object in experimental viewpoint but in conceptual viewpoint. We performed the experiment for 28 middle school students to investigate whether they understand this. As a result, the majority of student didn't cognize the limit of experimental method. We had also individual interviews with four students. As results, one student was exactly cognizing the limit of experimental method, but he couldn't prove logically. The others didn't cognize the limit of experimental method. They thought that the proposition was already true regardless of the error. And one of them even thought that to be equal approximately was the same of to be equal exactly. Also, one student has confused between the experimental viewpoint and the conceptual viewpoint. This implies that it is necessary to help students understand the limit of experimental method.

Elementary Students' Perception of the Science Inquiry Activities and Essential Features of Science Inquiry (과학 탐구 활동의 유형과 과학 탐구의 특징에 대한 초등학생의 인식)

  • Seong, Hyejin;Lim, Heejun
    • Journal of Korean Elementary Science Education
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    • v.37 no.4
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    • pp.391-401
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    • 2018
  • This study investigated elementary students' perception of the suitability of inquiry activities related to the science inquiry, essential features of the inquiry and essential features of the inquiry by science inquiry activities. First, 5-6th grade elementary students' perception of the suitability of inquiry activities to the science inquiry was positive in this study and especially the score of experiment and field trip was high. The lowest score was on the discussion and elementary students thought that discussion might be wrong, because they just talked when they participated in the discussion. Second, perception of the essential features of science inquiry was positive. Especially, engaging students in evaluating their explanations in the light of alternative explanations was the highest. Students thought that explanation is important, but it is too hard to perform the science inquiry with only the explanation. Third, the score of research and experiment was high in essential features of science inquiry by science inquiry activities. The score of the field trip was low, so a more meaningful field trip should be carried out in the school.

The Effect of Unconscious Thought on Goal-Dependent Decision Making (목표지향적 정보처리에서 무의식적 사고의 효과)

  • Kim, Min-Jeong;Lee, Young-Ai
    • Korean Journal of Cognitive Science
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    • v.22 no.4
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    • pp.405-427
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    • 2011
  • We explored whether unconscious thought affects the processing of scientific technology information concerning nuclear power. Instead of conscious deliberation of cost-benefit analysis of nuclear energy, we would like to show the effects of unconscious thought on decision making. Participants were presented with all information about nuclear power and then judged the most positive as well as the most negative items. Participants in the unconscious thought condition performed a 2-back digit memory task as distractor before they made any decision regarding the nuclear power. Those in conscious thought condition were asked to carefully evaluate all presented information while participants in the immediate decision condition made a quick decision. Based on the analysis of previous studies on this topic, we attempted to obtain the potential effects of unconscious thought by modifying materials and experimental procedures including the use of noise. Even with these new manipulations, the effect of unconscious thought on decision making was not observed in Experiment 1. In contrast, we observed a significant effect of unconscious thought on decision making when task purpose was clearly presented after participants have finished reading all information regarding nuclear power. The results of the present study indicate that if the task purpose were clearly presented, the effects of unconscious thoughts on decision making could be observed.

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The Effects of Scientific Experimental Classes Emphasized Small Group Argument Activities on Science Achievement and Scientific Attitudes (소집단 논의활동을 강조한 과학실험수업이 과학성취도 및 과학적 태도에 미치는 효과)

  • Kim, Soon-Shik
    • Journal of the Korean Society of Earth Science Education
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    • v.5 no.1
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    • pp.95-104
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    • 2012
  • The purpose of this study is to examine what effects the experiment class to stress discussion of small groups in scientific experiment class of the elementary school has on scientific achievement and attitude on the science of the students comparing to the usual scientific experiment class. For that purpose, this study has divided 49 students at the 6th grade of the M elementary school in P City into test groups of 24 students and control groups of 25 students. Classes have been progressed by giving sufficient time to the test groups for discussion by each small groups after experiment while by allowing the control groups to finish the experiment with arrangement of the experiment results. Conclusions of this study include: First, the more familiar the experiment materials are and the easier the experiment procedures are to be operated by the students, the more actively the small group discussion activities have been deployed. It shows that the students need a certain level of background knowledge before experiment for vital discussing activities. Second, it is appeared that the test groups given the scientific experiment class stressing small group discussing activity have significantly high scores comparing to the control groups given the existing scientific experiment class. It shows that the small group discussing activities have effects on promoting understanding of the students on the scientific achievement for the scientific experiment class. Third, it is appeared that the test groups given the scientific experiment class stressing small group discussing activity significantly high scores on attitude about the science comparing to the control groups given the existing scientific experiment class. It is considered that the students could have opportunities to compare their own thoughts with others and to have reflective thought to change their thoughts through the small group discussing activity. As shown above, it shows that the experiment class to stress discussing activities is more effective to increase scientific achievement and attitude about the science than the scientific experiment class to get and arrange the experiment results from the existing experiment classes.

Physiological Responses of Cold Protective Clothing with Different clo Value (보온력 차이에 따른 방한복 상의의 인체착의 생리반응)

  • Lee, Jung-Sug;Kim, Hee-Eun;Song, Min-Kyu
    • Fashion & Textile Research Journal
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    • v.10 no.5
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    • pp.683-689
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    • 2008
  • The purpose of this study was to investigate physiological responses such as rectal temperature, skin temperature, micro climate, sweat rate and subjective sensations using cold protective clothing with five different clo value. The clo value was measured by thermal manikin in windless condition. Healthy five 20's males volunteered as subjects for wearing trial experiment. The climate chamber was controlled at $50^{\circ}C$, 65% RH. The experiment consisted of repeated exercise and recovery periods. We found that the higher clo value has, the higher mean skin temperature, micro climate and sweat rate show. They felt warm and wet with higher insulation clothing. Thermal comfort increased in the last recovery period after exercise. There was significant difference between five cold protective clothing. In correlation analysis of clo value, it showed that correlation coefficient(r) values were more than 0.8. Therefore, in terms of clothing insulation, we found that correlation between thermal manikin experiment and wearing trial experiment was high. Clothing insulation could be variable according to many factors such as body movement, covering area, clothing gap, layering and design. Considering the body movement, we thought that insulation measurement need to carry out both thermal manikin experiment and wearing trial experiment.

A Study on the Channel Noise on VDT Workstation (VDT 작업환경에서 경로노이즈에 관한 연구)

  • Kwon, Kyu-Sik;Choi, Chul
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.25 no.1
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    • pp.71-77
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    • 2002
  • This study deals with noise occurring in the process of human information transmission. Human process many kinds of information by receiving them from the outside or using their own thought and express the processed information to the outside by acting. In this process, Channel Noise ($C_N$) is defined as the characteristics of noise generating the incomplete result for the external stimulus. To evaluate $C_N$, keyboard-typing experiment has been performed to the 87 subjects. In this experiment, the subject consists of college students who have abundant experience in computer usage. In the experiment, there were some cases that typing order was unconsciously reversed. In this study, we deal with only these cases since these cases can be used as important data to study humans information transmission system.