• Journal of Science and Technology Studies
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• v.1 no.1 s.1
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• pp.155-178
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• 2001

As is well known, logical positivists held the theory-independent of observation thesis(TIOT). On the other hand, the theories following the logical positivism typically represented by Hanson and Kuhn denied that there was a clear borderline between observation and theory, and held the theory-ladenness of observation thesis(TLOT). In order to mediate those theses I shall suggest a natural epistemic attitude (NEA) to the relation between theory and observation on the basis of the experimentalism. First, I discuss theories of Hanson and Kuhn as examples of views which profess TLOT. Then, I make a brief introduction of experimentalism and some critical discussions about TLOT follow from a point of the experimentalism: TLOT faces considerable counter-examples such as cases, 'observation precedes theory' and 'the combination of wrong theory and right observation'. I introduce a distinction between the guiding theory and the target theory in experimental situations and illustrate that TLOT loses its alleged power if we consider the distinction. Lastly, I suggest NEA, as conclusion of the paper, which can mediate among TIOT, TLOT, and experimentalism and takes a minimal ontology.

• Journal of The Korean Association For Science Education
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• v.30 no.1
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• pp.157-169
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• 2010

Scientific observation has been recognized as one of the fundamental aspects in scientific inquiry. However, more detailed discussions and practical guides for teachers' and students' understanding about the nature of scientific observation have not been conducted. Therefore, based on literature reviews, we described the nature of theory-laden scientific observation as 11 detailed statements. Using theses statements, we investigated science teachers' and students' recognition of each statement. According to results, certain aspects of theory-laden scientific observation were determined as important aspects to be considered for science teachers' in-service programs or for students' learning activities in understanding the nature of science.

• Journal of The Korean Association For Science Education
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• v.27 no.3
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• pp.169-179
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• 2007

We investigated the effects of hypothetical deductive experiment on students' views about the nature of science (NOS). Participants were 212 eighth graders from a middle school and they were assigned to a control group and an experimental group. Students of the control group did guided experiment in small group and students of the experimental group did hypothetical deductive experiment in small group. The results revealed that both students of the control group and the experimental group possessed similar views about NOS in a pretest. But the experimental group exhibited more sophisticated views about the theory of dependance of observation, scientific reasoning and hypothesis in the posttest. Students who used mainly surface learning strategy within the experimental group exhibited more sophisticated views about hypothesis in the posttest. On the other hand, students who used mainly deep learning strategy within the experimental group exhibited more sophisticated views about the theory of dependance of observation, scientific reasoning and hypothesis in the posttest.

• Korean Journal of Logic
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• v.17 no.2
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• pp.349-358
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• 2014

Human being has attempted to solve the problem of imperfect knowledge for a long time. In 1982 Pawlak proposed the rough set theory to manipulate the problem in the area of artificial intelligence. The rough set theory has two interesting properties: one is that a rough set is considered as distinct sets according to distinct knowledge bases, and the other is that distinct rough sets are considered as one same set in a certain knowledge base. This leads to a significant philosophical interpretation: a concept (or an event) may be understood as different ones from different perspectives, while different concepts (or events) may be understood as a same one in a certain perspective. This paper claims that such properties of rough set theory produce a mathematical model to support critical realism and theory ladenness of observation in the philosophy of science.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.4
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• pp.391-397
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• 2001

The guided wave propagation in inhomogeneous multi-layered structures is experimentally explored based on theoretical dispersion curves. It turns out that proper selection of incident angel and frequency is critical for guided wave generation in multi-layered structures. Theoretical dispersion curves greatly depend on adhesive zone thickness, layer thickness and material properties. It was possible to determine the adhesive zone thickness of an inhomogeneous multi-layered structure by monitoring experimentally the change of dispersion curves.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.243-246
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• 2004

W CMP 공정에서 abrasive 의 size 및 shape 에 따른 CMP 거동에 대해 관찰하였으며, 주요 제거 막질인 W 막질과 stopping layer 로 사용되는 Oxide 막질에 대한 압력(P)과 상대 속도(V) 영향성을 관찰하였다. CMP 제거량이 입자의 size 변화에 의존한다는 기존의 이론과는 달리 응집도(aggregate ratio) 변화가 주요 변수임을 밝혀 내었다. 한편, 각 막질에 대한 P,V 영향성 평가를 통해, 변형된 Prestonian equation 이 abrasive size 및 shape 에 상관없이 W 막질의 제거 거동을 설명하는데 중요한 역할을 수행함을 보였다. 그렇지만, W CMP 공정에서 stopping layer 로 사용되는 oxide 막질의 거동을 설명하는 데에는 어려움이 있었으며, 특히 P,V 에 의한 비선형적 removal rate(RR) 거동발생으로 인해 기존의 이론치와는 많은 차이를 나타내었다. 또한, abrasive size 와 shape 에 따라서도 복잡한 거동을 나타낸다.

• Clean Technology
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• v.20 no.2
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• pp.130-135
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• 2014

It is investigated that the surface properties of mercaptopyruvic-acid layer formed on gold surfaces may make an effect on the distribution of either gold particle adsorbed to the zirconia surface or vice versa. For the investigation, the atomic force microscope was used to measure the surface forces between the surfaces as a function of the salt concentration and pH value. The forces were quantitatively analyzed with the derjaguin-landau-verwey-overbeek (DLVO) theory to estimate the electrostatic properties, potential and charge density, of the surfaces for each condition of salt concentration and pH value. The estimatedvalue dependence on the salt concentration was explained with the law of mass action, and the pH dependence was interpreted with the ionizable groups on the surface. The salt concentration dependence of the surface properties, found from the measurement at pH 4 and 8, was predictable from the law. It was found that the mercaptopyruvic-acid layer had higher values for the surface charge densities and potentials than the zirconia surfaces at pH 4 and 8, which may be attributed to the ionizedfunctional-groups of the mercaptopyruvic-acid layer.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.1
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• pp.117-125
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• 1997

Ferroelastic $CsPbCl_3$ crystals were grown by the Czochralski method and Bridgman method. From XRD, DTA and the dielectric measurements, we investigated the structure and confirmed the phase transition temperatures of it. Using the polarizing microscope, we observed the ferroelastic domains and the temperature dependence of the domains. For the orientation states, we obtained the consistent result with the theoretical investigation by the crystallographical consideration. For Aizu species m3mF2/m(p) 12 orientation states are represented crystallographically.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.04b
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• pp.21-22
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• 1997

최근의 이온교환막은 종래의 양이온교환막의 표면에 polycation 등의 얇은 층을 덧붙인 다층막(multi-layer membrane)의 형태가 많이 이용되고 있으며, 정전기적 반발력의 차 등을 이용하여 원자가가 다른 이온들간의 투과성에 차를 부여하기 위하여 이용되고 있다. 이 때문에 polycation막을 통한 1가 이온과 2가 이온의 투과성을 연구하는 것은 우수한 이온교환막을 제작하는것 이상으로 중요하다. 본 연구에서는 고정전하농도(fixed charge density, $\Phi$ X)가 낮은 다공성 저전하음이온교환막을 제작하여, 양측에 대이온(counterion)은 같고 복이온(co-ion)이 다른 전해질용액을 두었을 경우에 관찰되는 막전위를 측정하였다. 이를 토대로 음이온교환막을 통한 막전위의 농도의존성에 관하여 검토하였으며, 비평형열역학(non-equilibrium thermodynamies)에 기초한 이론적 모델을 도입하여 실험치와 비교, 해석하였다.

• Journal of The Korean Association For Science Education
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• v.30 no.2
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• pp.206-217
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• 2010

This study aims to explore preservice teachers' overall views of nature of science and compare their views by gender and certificate area (biology vs. non-biology teachers). In addition, a comparison with American preservice teachers' views was also implemented. The Views of Nature of Science (Abd-El-Khalick, 1998), an openended questionnaire, is utilized to explore participants' views of nature of science. Along with 'definition of science', six aspects of the nature of science, (1) theories and laws, (2) tentativeness, (3) social and cultural embeddedness, (4) creativity, (5) theory-laden, and (6) inference, were investigated. The qualitative result indicates that the participants' first image of science was about the method of science such as observations and experiments. Furthermore, these preservice science teachers particularly have a difficulty in differentiating between scientific theories and laws, and understanding the importance of creation and imagination in developing scientific knowledge. In addition, compared to American preservice teachers' view of the nature of science, Korean preservice teachers possess naive views in creative and imaginative aspect. Interestingly, biology teachers demonstrated lower understanding in theories and laws as well as tentativeness of scientific knowledge. However, there is no difference by gender.