• Title/Summary/Keyword: good class

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A Statistical Perspective of Neural Networks for Imbalanced Data Problems

  • Oh, Sang-Hoon
    • International Journal of Contents
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    • v.7 no.3
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    • pp.1-5
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    • 2011
  • It has been an interesting challenge to find a good classifier for imbalanced data, since it is pervasive but a difficult problem to solve. However, classifiers developed with the assumption of well-balanced class distributions show poor classification performance for the imbalanced data. Among many approaches to the imbalanced data problems, the algorithmic level approach is attractive because it can be applied to the other approaches such as data level or ensemble approaches. Especially, the error back-propagation algorithm using the target node method, which can change the amount of weight-updating with regards to the target node of each class, attains good performances in the imbalanced data problems. In this paper, we analyze the relationship between two optimal outputs of neural network classifier trained with the target node method. Also, the optimal relationship is compared with those of the other error function methods such as mean-squared error and the n-th order extension of cross-entropy error. The analyses are verified through simulations on a thyroid data set.

Testing for Lack of Fit via the Generalized Neyman Smooth Test

  • Lee, Geung-Hee
    • Journal of the Korean Statistical Society
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    • v.27 no.3
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    • pp.305-318
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    • 1998
  • Smoothing tests based on an L$_2$ error between a truncated courier series estimator and a true function have shown good powers for a wide class of alternatives, These tests have the same form of the Neyman smooth test whose performance depends on the selected order, a basis, the farm of estimators. We construct flexible data driven Neyman smooth tests by changing a basis, combining model selection criteria and different series estimators. A simulation study shows that the generalized Neyman smooth test with the best basis provides good power for a wider class of alternatives compared with other data driven Neyman smooth tests based on a fixed form of estimator, a fixed basis and a fixed criterion.

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Numerical Simulation of Radial Strain Controlled Uniaxial and Triaxial Compression Test of Rock Using Bonded Particle Model (입자결합모델을 이용한 횡방향 변형률 제어 하에서의 암석의 일축 및 삼축압축시험의 수치적 모사)

  • Lee, Chang-Soo;Kwon, Sang-Ki;Jeon, Seok-Won
    • Tunnel and Underground Space
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    • v.21 no.3
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    • pp.216-224
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    • 2011
  • In this study, Class II behavior of rock failure process under uniaxial and biaxial compression has been numerically simulated using bonded particle model. Class II behavior of rock was simulated by radial strain controlled uniaxial and biaxial compression tests using a suggested method of ISRM. Micro-parameters used in the simulation were determined based on the laboratory uniaxial compression tests carried out at ${\"{A}}sp{\"{o}}$ Hard Rock Laboratory, Sweden. Class II behavior of ${\"{A}}sp{\"{o}}$ rock was effectively simulated using newly proposed numerical technique in this study, and the results of numerical simulations show good similarity with the complete stress-strain curves for Class II behavior obtained from the laboratory tests.

Electrical Characteristics of ZnO Varistor for Transmission Class Arrester (송전급 피뢰기용 ZnO 바리스터 소자의 전기적 특성)

  • Kim, Seok-Sou;Park, Choon-Hyun;Cho, I-Gon;Park, Tae-Gon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.04b
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    • pp.179-182
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    • 2004
  • ZnO varistor for transmission class arrester$({\Phi}65{\times}20mm)$ of 10kA(Class 3) grade was recently developed in korea and is tested for the properties by switching surge operating duty test to know the line discharge class and complex surge property in electric properties. To find out changing rate of residual voltage before and after lightning impulse residual voltage testing, the sample is cool to room temperature after finishing switching surge operating duty test, and the rate is good as 1.0~1.7%. The element had been considered as applicable ZnO varistor for electricity transmission from the test results of state conterl, switching surge operating duty, thermal stability and above test. But various test should be required for actual application because this is a part of the to be needed for application.

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The Effects of the Creative Thinking and Creative Personality Using the 'Weather and our life' on Science-Based STEAM (과학 기반 STEAM의 '날씨와 우리생활' 학습이 창의적사고 및 창의적 인성에 미치는 효과)

  • Lee, Yong-Seob;Kim, Yoon-Kyung
    • Journal of the Korean Society of Earth Science Education
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    • v.5 no.2
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    • pp.204-212
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    • 2012
  • The purpose of this study was to examine the effects of science-based STEAM on creative thinking and creative personality. For this study the 3 grade, 2 class was divided into a research group and a comparative group. The class was pre-tested in order to ensure the same standard. The research group had the science class with science-based STEAM, and the comparative group had the class with teacher centered lectures for 5 months. The science-based STEAM was focused on finding stories in lifes, composition of knowledge, completion of knowledge. The results of this study are as follows. First, science-based STEAM was effective in creative thinking. Second, science-based STEAM was effective in creative personality. Also, after using science-based STEAM was good reaction by students. As a result, the elementary science class with science-based STEAM had the effects of developing creative thinking and creative personality. it means the science class with creative personality has potential possibilities and value to develop creative thinking and creative personality.

Noisy label based discriminative least squares regression and its kernel extension for object identification

  • Liu, Zhonghua;Liu, Gang;Pu, Jiexin;Liu, Shigang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.5
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    • pp.2523-2538
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    • 2017
  • In most of the existing literature, the definition of the class label has the following characteristics. First, the class label of the samples from the same object has an absolutely fixed value. Second, the difference between class labels of the samples from different objects should be maximized. However, the appearance of a face varies greatly due to the variations of the illumination, pose, and expression. Therefore, the previous definition of class label is not quite reasonable. Inspired by discriminative least squares regression algorithm (DLSR), a noisy label based discriminative least squares regression algorithm (NLDLSR) is presented in this paper. In our algorithm, the maximization difference between the class labels of the samples from different objects should be satisfied. Meanwhile, the class label of the different samples from the same object is allowed to have small difference, which is consistent with the fact that the different samples from the same object have some differences. In addition, the proposed NLDLSR is expanded to the kernel space, and we further propose a novel kernel noisy label based discriminative least squares regression algorithm (KNLDLSR). A large number of experiments show that our proposed algorithms can achieve very good performance.

The Effects of Teacher's Beliefs about Mathematics on the Method of Class and the Performance of Problem Solving (교사의 수학에 대한 신념이 수업 방법과 학생의 문제해결 수행에 미치는 영향)

  • 김시년
    • Education of Primary School Mathematics
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    • v.3 no.1
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    • pp.79-88
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    • 1999
  • This paper shows how the social tradition and belief of korea on education affects teachers and students and learning. 1 Interview with teacher. During surveying this teacher's class, we knowed that the teacher have accentuated algorism loaming and preparation fur external examination in math class. Teacher's beliefs about mathematics have a strong effect on the method of class and the performance of problem solving 2. Interview with students and short test. 1) Students usually had fine ability of calculation for number. But Many pupils didn't know the meaning of the operations. 2) The most of pupils are good at routine math problem solving but when the question whose the condition don't meet was given, they experienced difficulties.3.Korean sociocultural specialty on education: The korean place high emphasis on education and think of education as the means of success. This emphasis can be traced to the Confucian view. 1) tradition on examination culture. 2) the traditional convention of the learning method. Korean sociocultural specialty on education play role of strengthen role learning and algorism class. The important things to education reformation are getting a balance between practice and understanding. we should make changes not only in national dimension but also in math class.

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On Approximation of Functions Belonging to Lip(α, r) Class and to Weighted W(Lr,ξ(t)) Class by Product Mean

  • Nigam, Hare Krishna;Sharm, Ajay
    • Kyungpook Mathematical Journal
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    • v.50 no.4
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    • pp.545-556
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    • 2010
  • A good amount of work has been done on degree of approximation of functions belonging to Lip${\alpha}$, Lip($\xi$(t),r) and W($L_r,\xi(t)$) and classes using Ces$\`{a}$ro, N$\"{o}$rlund and generalised N$\"{o}$rlund single summability methods by a number of researchers ([1], [10], [8], [6], [7], [2], [3], [4], [9]). But till now, nothing seems to have been done so far to obtain the degree of approximation of functions using (N,$p_n$)(C, 1) product summability method. Therefore the purpose of present paper is to establish two quite new theorems on degree of approximation of function $f\;\in\;Lip({\alpha},r)$ class and $f\;\in\;W(L_r,\;\xi(t))$ class by (N, $p_n$)(C, 1) product summability means of its Fourier series.

Analysis on Teachers' Perception of Questioning and Teaching Practices in Elementary Science Class (초등 과학 수업에서 나타나는 교사의 발문에 대한 인식과 실제 수업 분석)

  • Choi, Chui-Im;Cho, Min-Jung;Yeo, Sang-Ihn
    • Journal of Korean Elementary Science Education
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    • v.31 no.1
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    • pp.57-70
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    • 2012
  • We investigated the perception and preferred type of question and analyzed type of questions asked by teachers in elementary science class to identify how teachers' perception of questioning is reflected in teaching practices. We collected the data from questionnaires, deep-interview and audiotaped four classes from grade 3 and six classes from grade 6. The data form deep-interview were analyzed interpretively and Blosser' framework of question was used to analyze questions which teachers used in classes. By interpretation of data from questionnaires, the teachers agreed that questioning affects science class in elementary school. There were a little differences in perceptions of questioning among three teachers. They preferred various types of question rather than a specific type. They didn't have a good understanding of questioning. The result showed that the teachers used frequently cognitive-memory question and convergent thinking question, which belonged to closed questions in their science classes. This didn't accord with their preferred types of question. The causes came from objectives of science instruction, degree of understanding about questioning, preference and confidence for science class. From this findings, we suggested that teachers should be given opportunities to take training courses in questioning in order to use effective questioning in science class.

Propose an Improvement of Checklist for Actual Condition Survey for Designation of Class-lll Facilitie (제3종시설물 지정을 위한 실태조사 체크리스트 개선방안)

  • Yoon, Ji-Ho;Jang, Myunghoun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.100-101
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    • 2021
  • Facilities with high risk of a disaster or requiring continuous safety management are designated as class-III facility. In order to designate a class-III facility, it is evaluated based on the safety status of the facility, the risk to the building users, and the number of years elapsed of the facility, etc. and this shall be referred to the actual condition survey for the designation of a class-III facility. In the actual condition survey conducted to designate the safety status is calculated by the checklist based on the evaluation scores consisting of five stages each item, and is evaluated in three stages by 'good', 'careful observation', and 'designated review' through the average of the combined scores. Currently, the actual condition survey being conducted applies only structural stability, and the risk factors such as damage to the finish, the risk of cracking, and the type and weight of major structures are not included in the checklist for the actual condition survey, so even if experts think it is dangerous, scores cannot be reflected. Therefore, this study aims to analyze the problems of checklist of the actual condition survey for the designation of class-III facility and to propose an improvement plan for the checklist for the actual condition survey.

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