• Title/Summary/Keyword: random factor

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Antigenic-types of Salmonella pullorum and Salmonella gallinarum isolated from poultry in Korea (우리나라의 닭에서 분리한 Salmonella pullorum과 Salmonella gallinarum의 항원형)

  • Woo, Yong-ku;Kim, Bong-hwan
    • Korean Journal of Veterinary Research
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    • v.38 no.4
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    • pp.777-783
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    • 1998
  • Antigenic types of 114 Salmonella pullorum and 152 Salmonella gallinarum field isolates were evaluated. All 3 antigenic types were identified among field isolates of S pullorum by factor-serum analysis but the majority of them were standard type(90.4%). Of the 114 S pullorum isolates, only eight(7.0%) were intermediate type and 3(2.6%) were variant type. Using the ammonium sulfate precipitation(ASP) test, one-hundred and three(90.4%) S pullorum isolates were standard type, while intermediate and variant types were 8.4% and 1.4%, respectively. One-hundred and fifty-two S gallinarum isolates were identified as standard type by ASP test and serological analysis. According to the random amplified polymorphisms of DNA(RAPD) patterns, most of S pullorum isolates were differentiated with 3 types in their fragment-patterns. No correlations were found between SDS-PAGE profiles and antigenic types of S pullorum isolates.

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Multipath Channel Modeling for UWB (UWB 다중경로 전송환경 모델)

  • Bae Bag-Geun;Park Jin-Hwan;Ko Young-Eun;Choi Min-Sung;Bang Sung-Il
    • Proceedings of the IEEK Conference
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    • 2004.06a
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    • pp.23-26
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    • 2004
  • This paper analyzed time delay and phase distortion that generates in multipath and the degree of distortion due to power attenuation factor when UWB system is applied at indoor environment and the effects of indoor structure and material on distortion factors. Based on these distortion factors, channel model similar to actual environment is mathematically described and multipath and the degree of signal distortion generated when UWB system is applied to random environment is tested through channel model simulation and varies distortion factor that UWB system needs to consider in different indoor environment is analyzed.

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Design of MEMS Resonator Array for Minimization of Mode Localization Factor Subject to Random Fabrication Error (랜덤 제조 오차를 고려한 모드 편재계수를 최소화하는 반복 배열 마이크로 공진기의 최적설계)

  • Kim, Wook-Tae;Lee, Chong-Won
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.840-845
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    • 2005
  • This paper presents a robust optimal design method for a periodic structure type of MEMS resonator that is vulnerable to mode localization. The robust configuration of such a MEMS resonator to fabrication error is implemented by changing the regularity of periodic structure. For the mathematical convenience, the MEMS resonator is first modeled as a multi pendulum system. The index representing the measure of mode variation is then introduced using the perturbation method and the concept of modal assurance criterion. Finally, the optimal intentional mistuning, minimizing the expectation of the irregularity measure for each substructure, is determined for the normal distributed fabrication error and its robustness in the design of MEMS resonator to the fabrication error is demonstrated with numerical examples.

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Design of MEMS Resonator Array for Minimization of Mode Localization Factor Subject to Random Fabrication Error (랜덤 제조 오차를 고려한 모드 편재계수를 최소화하는 반복 배열 마이크로 공진기의 최적설계)

  • Kim, Wook-Tae;Lee, Chong-Won
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.15 no.8 s.101
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    • pp.931-938
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    • 2005
  • This paper presents a robust optimal design method for a periodic structure type of MEMS resonator that is vulnerable to mode localization. The robust configuration of such a MEMS resonator to fabrication error is implemented by changing the regularity of periodic structure For the mathematical convenience, the MEMS resonator is first modeled as a multi-pendulum system. The index representing the measure of mode variation is then introduced using the perturbation method and the concept of modal assurance criterion. Finally, the optimal intentional mistuning, minimizing the expectation of the irregularity measure for each substructure, is determined for the normal distributed fabrication error and its robustness in the design of MEMS resonator to the fabrication error is demonstrated with numerical examples.

Stochastic response spectra for an actively-controlled structure

  • Mochio, Takashi
    • Structural Engineering and Mechanics
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    • v.32 no.1
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    • pp.179-191
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    • 2009
  • A stochastic response spectrum method is proposed for simple evaluation of the structural response of an actively controlled aseismic structure. The response spectrum is constructed assuming a linear structure with an active mass damper (AMD) system, and an earthquake wave model given by the product of a non-stationary envelope function and a stationary Gaussian random process with Kanai-Tajimi power spectral density. The control design is executed using a linear quadratic Gaussian control strategy for an enlarged state space system, and the response amplification factor is given by the combination of the obtained statistical response values and extreme value theory. The response spectrum thus produced can be used for simple dynamical analyses. The response factors obtained by this method for a multi-degree-of-freedom structure are shown to be comparable with those determined by numerical simulations, demonstrating the validity and utility of the proposed technique as a simple design tool. This method is expected to be useful for engineers in the initial design stage for structures with active aseismic control.

Bayesian multiple comparisons in Freund's bivariate exponential populations with type I censored data

  • Cho, Jang-Sik
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.3
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    • pp.569-574
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    • 2010
  • We consider two components system which have Freund's bivariate exponential model. In this case, Bayesian multiple comparisons procedure for failure rates is sug-gested in K Freund's bivariate exponential populations. Here we assume that the com-ponents enter the study at random over time and the analysis is carried out at some prespeci ed time. We derive fractional Bayes factor for all comparisons under non- informative priors for the parameters and calculate the posterior probabilities for all hypotheses. And we select a hypotheses which has the highest posterior probability as best model. Finally, we give a numerical examples to illustrate our procedure.

Present and preferred design characteristics of major interior furnishings in the Gamsil apartment area of Gangdong-Ku -on the focus of sofa and tea table, curtain, and carpet- (아파트 실내장식물 디자인 특성의 실태 및 선호에 관한 연구 I - 강동구 잠실지역 아파트를 중심으로 -)

  • 이연숙
    • Journal of the Korean Home Economics Association
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    • v.23 no.4
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    • pp.123-141
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    • 1985
  • The purposes of this study were 1)to examine the present and the preferred design characteristics of major interior furnishings in the Gamsil apartment area of Gangdong-Ku and to investigate the relationship between those characteristics and residents' socioeconomic and their physical housing characteristics, 2) to determine the past and the future factor structures for attributes of the major furnishing, and , 3) to examine the change between the degree of the past and the future consideration on each of the attributes. The data for the study were collected using self-administered questionnaire. Households in Gamsil apartment area of Gangdong-Ku were the population. A proportional stratified systematic random sampling was employed. 480 questionnaires were distributed and 258 were collected. Among them, SAS package. The staticstics used were frequency, percentage, χ\sup 2\-test, factor analysis, and paired t-test.

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Coal Miners' Recognition and Attitude toward Pneumoconiosis in Kangneung Area (강릉지역 석탄광업 근로자의 진폐에 대한 인식 및 태도)

  • Chung, Ho-Keun;Rhee, Kyung-Yong
    • Journal of Preventive Medicine and Public Health
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    • v.21 no.2 s.24
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    • pp.251-266
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    • 1988
  • This study was planned in order to investigate coal miners' recognition and attitude toward pneumoconiosis, and its realtionship with related behavior for prevention of pneumoconiosis. Study object was coal miners in Kangneung area, sampled by multistage random proportional sampling. Sample size was 13% of total coal miners in Kangneung area. The results were devided into three parts: (1) descriptive results presented percent distribution, (2) reclassification of knowledge, experiences, and attitude by factor analysis, (3) prediction of health behavior for prevention of pneumoconiosis by discriminant analysis. Knowledge, experiences, and attitude toward pneumoconiosis were classified into nine factors. Knowledge about pneumoconiosis were broken down to two factors and attitude to four factors, and valence, perceived severity were classified into each one factor. According to demographic, socioeconomic characteristics, and factors of knowledge, experiences, attitude about pneumoconiosis, about 62% of behavior of wearing respiratory protector was correctly discriminated. And by the same methods, about 81% of behavior of hospital visit at respiratory symptoms; cough, sputum, chest pain etc. was discriminated correctly.

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Sampling Based Approach to Bayesian Analysis of Binary Regression Model with Incomplete Data

  • Chung, Young-Shik
    • Journal of the Korean Statistical Society
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    • v.26 no.4
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    • pp.493-505
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    • 1997
  • The analysis of binary data appears to many areas such as statistics, biometrics and econometrics. In many cases, data are often collected in which some observations are incomplete. Assume that the missing covariates are missing at random and the responses are completely observed. A method to Bayesian analysis of the binary regression model with incomplete data is presented. In particular, the desired marginal posterior moments of regression parameter are obtained using Meterpolis algorithm (Metropolis et al. 1953) within Gibbs sampler (Gelfand and Smith, 1990). Also, we compare logit model with probit model using Bayes factor which is approximated by importance sampling method. One example is presented.

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Characterization of Surface Roughness Using the Concept of Entropy in Machining (엔트로피 개념을 이용한 절삭가공에서 표면거칠기의 특성화)

  • 최기홍;최기상
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.12
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    • pp.3118-3126
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    • 1994
  • This paper describes the use of the concept of (relative) entropy for effective characterization of the amplitude and the frequency distributions of the surface profile formed in machining operation. For this purpose, a theoretical model for surface texture formation in turning operation is developed first. Then, the concept of (relative) entropy is reviewed and its effectiveness is examined based on the simulation and experimental results. The results also suggest that under random tool vibration the effect of the geometrical factors on the surface texture formation can be successfully decomposed and therefore, identified by applying the concept of (relative) entropy.