• Title/Summary/Keyword: Good science class

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The roles of public libraries on the cultural development of Korea (한국의 문화발전에 대한 공공도서관의 역할)

  • 박인웅
    • Journal of Korean Library and Information Science Society
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    • v.21
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    • pp.291-323
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    • 1994
  • The Result of the study can be summarized as follows : (1) Korean culture and public library look extremely wasted equally. Judging from this fact, I believe that it is impossible for public library can contribute to development of Korean culture. (2) But, public library can contribute to development of culture in the cultural environment that mental desire is prior to physical wants. This cultural environment can be built up with reading of good books. Therefore, if class to reading education and diverse reading education programs can be activated in a large portion of the nationwide public libraries and the majority of a local resident are capable of improving their creativity power, thinking power and imaginative faculty, public library can contribute to produce such cultural circumstances. (3) Quality, culture, a human and mind receive mu6 respect in Korean Society as advanced civil, democratic and industrial society in the future. The Society will be influenced by reason and rational culture will be suitable to this society. Creativity power, thinking-power, imaginative faculty, intelligence and power of information management are demanded to the greatest degree for the development of idea and new technology in the society under the control of rational culture. So, lifelong education with library use is the most fruitful and inexpensive way for the improvement of these powers.

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Molecular Modeling of Small Molecules as BVDV RNA-Dependent RNA Polymerase Allosteric Inhibitors

  • Chai, Han-Ha;Lim, Dajeong;Chai, Hee-Yeoul;Jung, Eunkyoung
    • Bulletin of the Korean Chemical Society
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    • v.34 no.3
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    • pp.837-850
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    • 2013
  • Bovine viral diarrhea virus (BVDV), a major pathogen of cattle, is a well-characterized pestivirus which has been used as a good model virus for HCV. The RNA-dependent RNA polymerase (RdRp) plays a key role in the RNA replication process, thus it has been targeted for antivirus drugs. We employed two-dimensional quantitative structure-activity relationship (2D-QSAR) and molecular field analysis (MFA) to identify the molecular substructure requirements, and the particular characteristics resulted in increased inhibitory activity for the known series of compounds to act as effective BVDV inhibitors. The 2D-QSAR study provided the rationale concept for changes in the structure to have more potent analogs focused on the class of arylazoenamines, benzimidazoles, and acridine derivatives with an optimal subset of descriptors, which have significantly contributed to overall anti-BVDV activity. MFA represented the molecular patterns responsible for the actions of antiviral compound at their receptors. We conclude that the polarity and the polarizability of a molecule play a main role in the inhibitory activity of BVDV inhibitors in the QSAR modeling.

Design of Small Antennas with Inductively Coupled Feed Using a Pareto Genetic Algorithm (Pareto 유전자 알고리즘을 이용한 초소형 유도결합 안테나 설계)

  • Cho Chihyun;Choo Hosung;Park Ikmo;Kim Youngkil
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.1 s.92
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    • pp.40-48
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    • 2005
  • In this paper, we explore the inductively coupled concept and propose a class of electrically small planar antennas. The antennas are optimized using NEC in conjunction with a Pareto GA. These antennas show good efficiency and bandwidth performance without any additional matching network. Several optimized designs are fabricated and measured. We explain the operating principle of these antennas using a simple lumped element circuit model. The proposed antennas are translated as printed lines on Duroid for RFID tag antennas.

A quantification study of blood test results for dyspnea patients (호흡곤란 환자에 대한 혈액검사 결과들의 수량화 연구)

  • Park, Cheol-Yong
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.3
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    • pp.477-485
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    • 2011
  • Park et. al (2010) proposed a statistical model for determining the admission or discharge of 668 patients with a chief complaint of dyspnea by the number of 11 blood tests belonging to the corresponding discharge intervals. Since this method does not take into consideration the importance of each blood test result, its performance might not be optimally good. In this study, we employ a quantification method to evaluate the importance of those blood test results, and then provide a new statistical mode that takes the importance into consideration. The results show that the performance of this new model is a little better than that of the model by Park et. al (2010).

Rotordynamic Performance Measurements of An Oil-Free Turbocharger Supported on Gas Foil Bearings and Their Comparisons to Floating Ring Bearings

  • Lee, Yong-Bok;Park, Dong-Jin;Sim, Kyuho
    • International Journal of Fluid Machinery and Systems
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    • v.8 no.1
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    • pp.23-35
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    • 2015
  • This paper presents the rotordynamic performance measurement of oil-free turbocharger (TC) supported on gas foil bearings (GFBs) for 2 liter class diesel vehicles and comparison to floating ring bearings (FRBs). Oil-free TC was designed and developed via the rotordynamic analyses using dynamic force coefficients from GFB analyses. The rotordynamics and performance of the oil-free TC was measured up to 85 krpm while being driven by a diesel vehicle engine, and compared to a commercial oil-lubricated TC supported on FRBs. The test results showed that the GFBs increased the rotor speed by ~ 20% at engine speeds of 1,500 rpm and 1,750 rpm, yielding the reduction of turbine input energy by more than 400 W. Incidentally, an external shock test on the oil-free TC casing was conducted at the rotor speed of 60 krpm, and showed a good capability of vibration damping due to the well-known dry friction mechanism of the GFBs.

A Simple Mlodel for Dispersion in the Stable Boundary Layer

  • Sung-Dae Kang;Fuj
    • Journal of Environmental Science International
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    • v.1 no.1
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    • pp.35-43
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    • 1992
  • Handling the emergency problems such as Chemobyl accident require real time prediction of pollutants dispersion. One-point real time sounding at pollutant source and simple model including turbulent-radiation process are very important to predict dispersion at real time. The stability categories obtained by one-dimensional numerical model (including PBL dynamics and radiative process) are good agreement with observational data (Golder, 1972). Therefore, the meteorological parameters (thermal, moisture and momentum fluxes; sensible and latent heat; Monin-Obukhov length and bulk Richardson number; vertical diffusion coefficient and TKE; mixing height) calculated by this model will be useful to understand the structure of stable boundary layer and to handling the emergency problems such as dangerous gasses accident. Especially, this simple model has strong merit for practical dispersion models which require turbulence process but does not takes long time to real predictions. According to the results of this model, the urban area has stronger vertical dispersion and weaker horizontal dispersion than rural area during daytime in summer season. The maximum stability class of urban area and rural area are "A" and "B" at 14 LST, respectively. After 20 LST, both urban and rural area have weak vertical dispersion, but they have strong horizontal dispersion. Generally, the urban area have larger radius of horizontal dispersion than rural area. Considering the resolution and time consuming problems of three dimensional grid model, one-dimensional model with one-point real sounding have strong merit for practical dispersion model.al dispersion model.

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Bacterial community comparison revealed by metagenomic analysis and physicochemical properties of eastern little tuna (Euthynnus affinis) with storage temperature differences

  • Asadatun Abdullah;Rahadian Pratama;Tati Nurhayati;Windy Sibuea;Sabila Diana Ahmad Sauqi
    • Fisheries and Aquatic Sciences
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    • v.26 no.10
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    • pp.593-604
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    • 2023
  • Post-harvest handling and hygienic level of aquatic products significantly affect the quality and level of safety. Cold chain control is one of the determining factors for the quality of fish and the bacterial community that grows on the fish. Identification of spoilage bacteria and pathogens in aquatic products must be made because it will determine the physical and chemical quality. A molecular identification method with high sensitivity is the solution. This study aims to identify the quality of fish and bacterial communities that grow. The research procedures included sample collection, pH measurement, drip loss measurement, transportation and cold storage treatment, DNA extraction, DNA sequencing, sequence analysis, and bioinformatics analysis. The conclusion obtained from this study is that the simulation of the cold chain system applied to eastern little tuna does not significantly affect changes in the water activity value, pH, and drip loss. The insignificant change indicates that the eastern little tuna samples are still in good quality. The bioinformatics analysis showed the highest diversity and abundance of the bacterial community came from the Gammaproteobacterial class.

Semi-Supervised SAR Image Classification via Adaptive Threshold Selection (선별적인 임계값 선택을 이용한 준지도 학습의 SAR 분류 기술)

  • Jaejun Do;Minjung Yoo;Jaeseok Lee;Hyoi Moon;Sunok Kim
    • Journal of the Korea Institute of Military Science and Technology
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    • v.27 no.3
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    • pp.319-328
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    • 2024
  • Semi-supervised learning is a good way to train a classification model using a small number of labeled and large number of unlabeled data. We applied semi-supervised learning to a synthetic aperture radar(SAR) image classification model with a limited number of datasets that are difficult to create. To address the previous difficulties, semi-supervised learning uses a model trained with a small amount of labeled data to generate and learn pseudo labels. Besides, a lot of number of papers use a single fixed threshold to create pseudo labels. In this paper, we present a semi-supervised synthetic aperture radar(SAR) image classification method that applies different thresholds for each class instead of all classes sharing a fixed threshold to improve SAR classification performance with a small number of labeled datasets.

How did Elementary Teachers Handle Critical Experiments in Science Classrooms?

  • Kwon, Sung-Gi;Lee, Mi-Kyoung;Nam, Il-Kyun
    • Journal of Korean Elementary Science Education
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    • v.28 no.2
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    • pp.105-120
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    • 2009
  • Critical Experiments (CE) in science classrooms mean, tentatively, critical situations as comparable to anomalous cases in scientific revolutions where the results of science experiments in schools are unclear, differ from the theory, or students misunderstand the purpose of the experiments. The purpose of this research is to identify what CE occurred during science classes and to investigate how elementary teachers handled them. To analyze how teachers recognized and handled CE, we selected nine typical CE from the $7^{th}$ Korean science curriculum. 125 teachers were selected from 8 districts' elementary schools in a local city. A questionnaire with photos of the nine CE above-mentioned was distributed to these teachers. The focus in this research was the way that each teacher handled the CE. We discovered that there were three basic ways in which teachers handled CE. When CE occurred, 51% of elementary teachers explained the correct result of the experiment (what should have happened) to the students while 40.7% of the teachers repeated to get the correct results. The focuses of handling CE varied. 57 % of the teachers focused on the 'materials' while 30% of the teachers focused on the 'theory'. The other focus was 'thinking'. Only 7.6% of the teachers answered that they gave students a chance to think about the reasons why the CE happened. By analyzing our survey results, we could determine what each teacher did as a follow up to the CE and their focus and reasoning for handling the CE this way. When the CE happened in the science class, few handled the CE with the point of view about purpose of doing experiment. As a result, students could not gain educational experience from the CE. If we use CE as a new method to teach science, it will be a good subject incorporating the nature of science in science education.

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Principal Discriminant Variate (PDV) Method for Classification of Multicollinear Data: Application to Diagnosis of Mastitic Cows Using Near-Infrared Spectra of Plasma Samples

  • Jiang, Jian-Hui;Tsenkova, Roumiana;Yu, Ru-Qin;Ozaki, Yukihiro
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1244-1244
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    • 2001
  • In linear discriminant analysis there are two important properties concerning the effectiveness of discriminant function modeling. The first is the separability of the discriminant function for different classes. The separability reaches its optimum by maximizing the ratio of between-class to within-class variance. The second is the stability of the discriminant function against noises present in the measurement variables. One can optimize the stability by exploring the discriminant variates in a principal variation subspace, i. e., the directions that account for a majority of the total variation of the data. An unstable discriminant function will exhibit inflated variance in the prediction of future unclassified objects, exposed to a significantly increased risk of erroneous prediction. Therefore, an ideal discriminant function should not only separate different classes with a minimum misclassification rate for the training set, but also possess a good stability such that the prediction variance for unclassified objects can be as small as possible. In other words, an optimal classifier should find a balance between the separability and the stability. This is of special significance for multivariate spectroscopy-based classification where multicollinearity always leads to discriminant directions located in low-spread subspaces. A new regularized discriminant analysis technique, the principal discriminant variate (PDV) method, has been developed for handling effectively multicollinear data commonly encountered in multivariate spectroscopy-based classification. The motivation behind this method is to seek a sequence of discriminant directions that not only optimize the separability between different classes, but also account for a maximized variation present in the data. Three different formulations for the PDV methods are suggested, and an effective computing procedure is proposed for a PDV method. Near-infrared (NIR) spectra of blood plasma samples from mastitic and healthy cows have been used to evaluate the behavior of the PDV method in comparison with principal component analysis (PCA), discriminant partial least squares (DPLS), soft independent modeling of class analogies (SIMCA) and Fisher linear discriminant analysis (FLDA). Results obtained demonstrate that the PDV method exhibits improved stability in prediction without significant loss of separability. The NIR spectra of blood plasma samples from mastitic and healthy cows are clearly discriminated between by the PDV method. Moreover, the proposed method provides superior performance to PCA, DPLS, SIMCA and FLDA, indicating that PDV is a promising tool in discriminant analysis of spectra-characterized samples with only small compositional difference, thereby providing a useful means for spectroscopy-based clinic applications.

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