• Title/Summary/Keyword: multiple scales

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Bayesian Analysis for Categorical Data with Missing Traits Under a Multivariate Threshold Animal Model (다형질 Threshold 개체모형에서 Missing 기록을 포함한 이산형 자료에 대한 Bayesian 분석)

  • Lee, Deuk-Hwan
    • Journal of Animal Science and Technology
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    • v.44 no.2
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    • pp.151-164
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    • 2002
  • Genetic variance and covariance components of the linear traits and the ordered categorical traits, that are usually observed as dichotomous or polychotomous outcomes, were simultaneously estimated in a multivariate threshold animal model with concepts of arbitrary underlying liability scales with Bayesian inference via Gibbs sampling algorithms. A multivariate threshold animal model in this study can be allowed in any combination of missing traits with assuming correlation among the traits considered. Gibbs sampling algorithms as a hierarchical Bayesian inference were used to get reliable point estimates to which marginal posterior means of parameters were assumed. Main point of this study is that the underlying values for the observations on the categorical traits sampled at previous round of iteration and the observations on the continuous traits can be considered to sample the underlying values for categorical data and continuous data with missing at current cycle (see appendix). This study also showed that the underlying variables for missing categorical data should be generated with taking into account for the correlated traits to satisfy the fully conditional posterior distributions of parameters although some of papers (Wang et al., 1997; VanTassell et al., 1998) presented that only the residual effects of missing traits were generated in same situation. In present study, Gibbs samplers for making the fully Bayesian inferences for unknown parameters of interests are played rolls with methodologies to enable the any combinations of the linear and categorical traits with missing observations. Moreover, two kinds of constraints to guarantee identifiability for the arbitrary underlying variables are shown with keeping the fully conditional posterior distributions of those parameters. Numerical example for a threshold animal model included the maternal and permanent environmental effects on a multiple ordered categorical trait as calving ease, a binary trait as non-return rate, and the other normally distributed trait, birth weight, is provided with simulation study.

Nonlinear Analysis of a Forced Beam with Internal Resonances (내부공진을 가진 보의 비선형 강제진동해석)

  • 이원경;소강영
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1991.04a
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    • pp.147-152
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    • 1991
  • 양단이 고정된 보가 변형할 때에는 중간 평면의 신장을 수반하게 된다. 운동 의 진폭이 증가함에 따라 이 신장이 보의 동적 응답에 미치는 영향은 심각 하게 된다. 이러한 현상은 응력과 변형도와의 관계가 선형적이라 하더라도 변형도와 변위와의 관계식은 비선형이 되며 결국은 보의 비선형 운동방정식 을 낳게된다. 보는 연속계이긴하지만 근사를 위하여 다자유도계로 간주할 수 있다. 비선형 다자유도계에 있어서는 선형화된 계의 고유진동수끼리 적절한 관계를 가질 때 내부공진이 발생할 수 있다. 양단이 고정된 곧은 보의 비선 형 동적응답이 그동안 많이 연구되어 오고 있으며, 집중질량을 가지고 직각 으로 굽은 보의 해석을 위하여 내부공진을 고려한 해석적 혹은 실험적 연구 가 이루어져 왔다. 그중에서도 Nayfeh등은 조화가진 하의 핀과 꺾쇠로 고정 된(hinged-clamped) 보의 정상상태응답을 해석하기 위해 두 모우드 사이의 내부공진을 고려하였다. 이 연구에서는 세 모우드 사이의 내부공진을 고려하 여 강제진행 중인 보의 비선형 해석을 다루고자 한다. 이 문제에 관심을 갖 게 된 동기는 "연속계의 비선형 해석에서 더 많은 모우드를 포함시키면 어 떤 결과를 낳게 될 것인가\ulcorner"라는 질문에서 생겨난 것이다. 갤러킨 법을 이용 하여 비선형 편미분 방정식과 경계 조건으로 표현되는 이 문제를 연립 비선 형 상미분 방정식으로 변환한다. 다중시간법(the method of multiple scales) 을 이용하여 이 상미분 방정식을 정상상태에서의 세 모우드의 진폭과 위상 에 대한 연립비선형 대수방정식으로 변환한다. 이 대수방정식을 수치적으로 풀어서 정상상태 응답을 구하고 Nayfeh등의 결과와 비교한다. 결과와 비교한다. studies, the origin of ${\alpha}$$_1$peak was attributed to the detrapping process form trap with 2.88[eV] deep of injected space charge from the chathode in the crystaline regions. The origin of ${\alpha}$$_2$ peak was regarded as the detrapping process of ions trapped with 0.9[eV] deep originated from impurity-ion remained in the specimen during production process of the material, in the crystalline regions. The origin of ${\beta}$ peak was concluded to be due to the depolarization process of "C=0"dipole with the activation energy of 0.75[eV] in the amorphous regions. The origin of ${\gamma}$ peak was responsible to the process combined with the depolarization of "CH$_3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorp

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Variables Associated with School-Related Adjustment of Technical High School Students (공업계 고등학교 학생들의 학교생활 적응과 관련 변인)

  • Lee, Myung-Hun
    • 대한공업교육학회지
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    • v.32 no.2
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    • pp.1-22
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    • 2007
  • The purposes of this study were to measure the school-related adjustment level of technical high school students, and to determine the relationship between school-related adjustment and its related variables. The study was carried out through questionnaire survey method. The population sample for the study constituted 553 completed questionnaires from purposive sample of 600 first grade technical high school students. A survey questionnaire was developed by researcher, which consisted of 28 scales. Both descriptive and inferential statistics were employed for data analysis. Major findings of this study were as follows: First, school-related adjustment level of technical high school students was average. In sub-variables of school-related adjustment, 'compliance with the rule' was the highest, and 'relation to teacher' was the lowest. Second, five related variables were found to be a significant relationship with school-related adjustment level of technical high school students. They were 'orientation for freshman', 'student's department hope', 'teacher activity for student learning improvement', 'teacher support for student school life', 'parent's interest about school life'. Third, after multiple regression analysis, the proportion of the variance in school-related adjustment of technical high school students was about 42.2%. School-related adjustment of technical high school students was most explained by 'teacher activity for student learning improvement'.

Pipeline Structural Damage Detection Using Self-Sensing Technology and PNN-Based Pattern Recognition (자율 감지 및 확률론적 신경망 기반 패턴 인식을 이용한 배관 구조물 손상 진단 기법)

  • Lee, Chang-Gil;Park, Woong-Ki;Park, Seung-Hee
    • Journal of the Korean Society for Nondestructive Testing
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    • v.31 no.4
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    • pp.351-359
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    • 2011
  • In a structure, damage can occur at several scales from micro-cracking to corrosion or loose bolts. This makes the identification of damage difficult with one mode of sensing. Hence, a multi-mode actuated sensing system is proposed based on a self-sensing circuit using a piezoelectric sensor. In the self sensing-based multi-mode actuated sensing, one mode provides a wide frequency-band structural response from the self-sensed impedance measurement and the other mode provides a specific frequency-induced structural wavelet response from the self-sensed guided wave measurement. In this study, an experimental study on the pipeline system is carried out to verify the effectiveness and the robustness of the proposed structural health monitoring approach. Different types of structural damage are artificially inflicted on the pipeline system. To classify the multiple types of structural damage, a supervised learning-based statistical pattern recognition is implemented by composing a two-dimensional space using the damage indices extracted from the impedance and guided wave features. For more systematic damage classification, several control parameters to determine an optimal decision boundary for the supervised learning-based pattern recognition are optimized. Finally, further research issues will be discussed for real-world implementation of the proposed approach.

Relationship between Characteristics of Five Types of Obese Woman based on Physical Tests and Fei-kao-liuren based on Oriental Medical Theory (여성(女性) 비만(肥滿) 유형별 검사특성과 비고육인(肥膏肉人)과의 관계)

  • Jin Seng-Hee;Choi Kyung-Mee;Park Young-Bae
    • The Journal of Korean Medicine
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    • v.27 no.2 s.66
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    • pp.145-154
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    • 2006
  • Objectives : Methods to evaluate obesity are growing to be important in studying links between health and disease. Physicians are using BMI (body mass index) to evaluate obesity, but they can't know how much fat the body has by using that method. Even though there are several assessments, there are different scales, so patients are diagnosed as obese, by some but not by others. These studies are limited in evaluating obesity; it is necessary to study based on new knowledge. According to Oriental Medical Theory, obese people are categorized into 3 types, Fei, Kao and Liu Ren. They have different pathology and body shapes than non-obese people. The relationship between Oriental Medical Theory and BMI and assessment of body fat is a fundamental need to easily approach and treat obesity. Methods : At 00 Oriental Medical Center, 145 female subjects who intended to lose weight were given physical tests and grouped into 5 types of obesity. The physical tests were height measurement, BMI, body composition (body fat mass and lean body mass), skin elasticity and physical strength tests. One-way analysis of variance was done to compare the means of physical tests between the five types of obese women. There was some relationship between characteristics of the five types based on physical tests and Fei, Kao and Liu Ren based on Oriental Medical Theory. Least significant difference (LSD) was used in multiple comparisons. Results : 1. According to the skin elasticity test, obesity type 5 placed between obesity types 3 and 4 and obesity types 1 and 2. Obesity types 3 and 4 were in the low skin elasticity result group; obesity types 1 and 2 were in the high ones (p<0.1).Based on Oriental Medical Theory, Fei Ren and Kao Ren can be distinguished by skin elasticity degree. This result should form the basis of obesity diagnosis. 2. According to Oriental Medical Theory, Fei Ren is smaller than others. Based on height measurement, obesity types 3 and 4 were significantly lower than other obesity types (p<0.1), so there is a relationship between Fei Ren and obesity types 3 & 4. 3. There were significant differences between obesity type 2 and obesity type 4 in the body fat mass result (p<0.1). This study did not have large enough a sample size to distinguish Liu Ren. Conclusions : Further clinical research is necessary to study measurement methods of body shape type and skin elasticity for distinguishing Fei Ren from Kao Ren. The diagnosis and treatment based on the relationship of these types should be studied further.

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A Comparative Study on the Methods for Weighting the Dimensions of Customer Satisfaction with Importance Perceived by Customers (고객만족도 조사도구의 차원별 가중치 부여방법 비교)

  • Kang, Myunggeun;Cho, Woohyun;Lee, Sunhee;Choi, Kuison;Mooon, Kitae
    • Quality Improvement in Health Care
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    • v.7 no.2
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    • pp.230-242
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    • 2000
  • Background : The measuring instruments for customer satisfaction in hospitals are often composed of some dimensions reflecting the conceptive complexity of them. Then, overall satisfaction would be expected to be equal the 'weighted' sum of scores by dimensions because the importance rated by customers may be different across the dimensions. But the issue of how to weight the dimensions with importance is not yet solved. We examined 3 sets of weighting methods as to make effect on predictive power against overall satisfaction. Methods : We conducted a survey included 483 subjects who had visited or admitted to a university hospital, using the short form questionnaire being developed by The Korean Society of Quality Assurance in Health Care for out-patient and in-patient. By using a multiple linear regression model, we compared among changes of explanatory powers against overall satisfaction as dependent variable after weighting 4 dimensions of the survey questionnaire as independent variables with importance scores of dimensions perceived by consumers. And we compared the feasibility of each weighting, methods by checking missing cases. Results : There were no weighting methods increasing the explanatory power after applying them. The method of absolute scoring was found higher explanatory-power than others, but this finding had no statistical significance. Regarding the number of missing value, method of absolutely scoring had the least cases. Conclusion : Our findings suggested that weighting the dimensions with importance might have little significance in the cases of scales having items highly correlated, such as consumers' satisfaction. Though asking with items to be answered absolutely, customers might be rating relatively in some degree and this method produced least missing cases. Considering these points, in the cases when weighting the dimensions with importance would be required, we suggest that weighting method by absolute scoring might be better than others.

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A Study on the Introduction of Linear Programming Model into the Management of Korean Coastal and Offshore Fisheries (한국 연근해어업의 합리적 관리를 위한 LP모형의 도입방안에 관한 연구)

  • 박장일
    • The Journal of Fisheries Business Administration
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    • v.25 no.1
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    • pp.37-59
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    • 1994
  • Many studies to cope with the present problems of Korean coastal and offshore fisheries has been performed, but these were done partly in necessities and general studies for Korean inshore and offshore fisheries are in early stage. Most of these studies adopted analytical way of approach for each fishery individually and they could not reflect the effect of correlated interaction among fisheries on the several common species/stocks, and thus optimal effort allocation was impossible. To consider general fisheries and optimal effort allocation among competing mixed species, a linear programming (LP) approach is applied in this study and introduced into 16 important inshore and offshore fisheries with 13 constraining species which were chosen by annual yield order. This study is not based on the biological interaction among species (i.e., prey - predator system) but the technological interaction between species and fishing efforts. For the application of LP model in these fisheries, the standardization of fishing efforts through different fishing gears could not be successful and a new way of effort standardization through CPUE for vessel tonnage was originated. Total standardized fishing effort on a particular species i, Ei, is computed as the linear summation of standardized fishing effort generated by each fishery j. That is, (equation omitted) where $f_{j}$ is the total vessel tonnage of fishery j and aij is the coefficients contributing to the standardized fishing effort per ton for species i taken in fishery j. The total fishing effort level on species i due to both directed fishing and by - catch can thus be accounted in the aij's. Optimal effort allocation among the j fisheries may be considered a minimizing problem (minimize $\Sigma$ $f_{j}$), subject to the constraints that standardized fishing effort levels on particular species are maintained at, above, and below certain predefined levels. Fishing effort goals for individual species can be based on various biological and/or economic criteria, i.e., fishing effort level generating maximum sustainable yield and/or maximum economic yield. But in this study the $F_{0.1}$ criteria which was accepted as an approximate level for $F_{mey}$ by Outland and Boerema's (1973) study. The findings of this study are, (1) LP model can be applied to the Korean inshore and offshore fisheries giobally. (2) Through a new way of combining multiple different fisheries' efforts for a particular species together generating standardized fishing effort, Schaefer curve could be applied to the complex system successfully. (3) The results of this study for total reduction scale were mostly the same as those of prior studies, but different much from the individual scales of reduction. This study showed the necessities for exploitation of more concrete parameters to put into consideration of profitability of fisheries and social factors, and this model can be modified according to the actual constraints. Also, considering the age structure of stocks, this model can be developed into better one for better fisheries management.ent.

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The Moderating Effect of Teacher-Child Relationship on the Relation between Child's Shyness and Peer Victimization (남녀 유아의 수줍음과 또래괴롭힘 피해 간 관계에 대한 교사-유아 관계의 중재효과)

  • Kwon, Yeon Hee
    • Korean Journal of Childcare and Education
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    • v.10 no.5
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    • pp.25-45
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    • 2014
  • This study examined the moderating role of teacher-child relationship on the relation between children's shyness and peer victimization. Participants were 200 children(97 boys, 103 girls; recruited from classes with 5-6 year olds) and their kindergarten teachers. The teachers completed rating scales to measure the children's peer victimization, shyness and teacher-child relationship. The collected data were analyzed using descriptive statistics, t-tests, correlations, and hierarchical multiple regressions. Boys and girls were analyzed separately. Results showed that children's shyness had a positive relation to their peer victimization. Teacher-child relationship significantly related to children's peer victimization. Hierarchical regression analysis indicated that the interaction of boys' shyness and teacher-child closeness predicted boys' peer victimization. Boys' shyness, whose teachers demonstrated the lowest level of teacher-child closeness, was significantly associated with their peer victimization. Boys' shyness had a significant relation to their peer victimization, especially for the highest level of teacher-child conflictual relationship. Results are discussed in terms of the role of teachers to shy boys' peer victimization.

The Effects of Mothers' Rejective Parenting, Emotional Expressivity and Children's Emotional Regulation Strategy on their Social Withdrawal (유아의 사회적 위축에 대한 어머니의 거부적 양육행동과 정서표현성 및 유아의 정서조절전략의 영향)

  • Kwon, Yeon Hee
    • Korean Journal of Childcare and Education
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    • v.9 no.2
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    • pp.215-238
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    • 2013
  • This study examined the effects of mothers' rejective parenting, emotional expressivity, children's emotional regulation strategy on their social withdrawal. Participants were 223 children(121 boys, 102 girls; recruited from classes with 4-5 year olds), their mothers and 20 child care teachers. The teachers completed rating scales to measure the children's social withdrawal and emotional regulation strategies. Mothers reported their rejective parenting along with emotional expressivity. The collected data were analyzed using descriptive statistics, Pearson's productive correlation coefficient, and hierarchical multiple regressions. Results showed that mothers' rejective parenting, children's venting/support seeking strategy and avoidance/non-responsive strategy had positive relation to, whereas mother's positive expressivity were negatively related to their social withdrawal. Hierarchical regression analysis indicated that the interaction of mother's rejective parenting and positive expressivity predicted children's social withdrawal. Mother's rejective parenting was associated with children's social withdrawal, especially for children with the lowest level of mother's positive expressivity. In addition, the association between mother's rejective parenting and children's social withdrawal were partially mediated by their venting/support seeking strategy.

Development of Road Surface Management System using Digital Imagery (수치영상을 이용한 도로 노면관리시스템 개발)

  • Seo, Dong-Ju
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.1
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    • pp.35-46
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    • 2007
  • In the study digital imagery was used to examine asphalt concrete pavements. With digitally mastered-image information that was filmed with a video camera fixed on a car travelling on road at a consistent speed, a road surface management system that can gain road surface information (Crack, Rutting, IRI) was developed using an object-oriented language "Delphi". This system was designed to improve visualized effects by animations and graphs. After analyzing the accuracy of 3-D coordinates of road surfaces that were decided using multiple image orientation and bundle adjustment method, the average of standard errors turned out to be 0.0427m in the X direction, 0.0527m in the Y direction and 0.1539m in the Z direction. As a result, it was found to be good enough to be put to practical use for maps drawn on scales below 1/1000, which are currently producted and used in our country, and GIS data. According to the analysis of the accuracy in crack width on 12 spots using a digital video camera, the standard error was found to be ${\pm}0.256mm$, which is considered as high precision. In order to get information on rutting, the physically measured cross sections of 4 spots were compared with cross sections generated from digital images. Even though a maximum error turned out to be 10.88mm, its practicality is found in work efficiency.

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