• Title/Summary/Keyword: Hybrid Function

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Development of a High-Order Accurate Hybrid Scheme Using the Central Flux and WENO Schemes (Central Flux Scheme과 WENO Scheme을 이용한 고차 정확도 Hybrid Scheme의 개발)

  • Kim D.;Kwon J. H.
    • 한국전산유체공학회:학술대회논문집
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    • 2005.04a
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    • pp.135-141
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    • 2005
  • A hybrid central-WENO scheme is proposed. The fifth order WENO-LF scheme is coupled with a central flux scheme at cell face. Two sub-schemes, the WENO-LF scheme and the central flux scheme, are switched by a weighting function. The efficiency and accuracy of the proposed hybrid central-WENO scheme is validated through several numerical experiments.

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Proposed New Encoders Using a Hybrid approach (하이브리드방식을 이용한 새로운 엔코더의 제안)

  • Kim, Young-Su;Kwon, Soon-Jae
    • Proceedings of the KIPE Conference
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    • 2016.07a
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    • pp.371-372
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    • 2016
  • In this paper, the encoder of the hybrid type which can use a single position sensor in order to overcome the use of multiple signal lines and the reliability reduction for the location information acquisition caused by using a plurality of position detectors to acquire the position information of the rotor offer. Encoder of the proposed method was the replacement location information generating function by the plurality of sensors to the Capture function of the shape and the microcomputer of the encoder plate. Capture of the DSP function was verified through experiments using the in order to verify the validity of the detection by the proposed method and the hybrid encoder position prototyping, a means.

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Estimation of the exponentiated half-logistic distribution based on multiply Type-I hybrid censoring

  • Jeon, Young Eun;Kang, Suk-Bok
    • Communications for Statistical Applications and Methods
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    • v.27 no.1
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    • pp.47-64
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    • 2020
  • In this paper, we derive some estimators of the scale parameter of the exponentiated half-logistic distribution based on the multiply Type-I hybrid censoring scheme. We assume that the shape parameter λ is known. We obtain the maximum likelihood estimator of the scale parameter σ. The scale parameter is estimated by approximating the given likelihood function using two different Taylor series expansions since the likelihood equation is not explicitly solved. We also obtain Bayes estimators using prior distribution. To obtain the Bayes estimators, we use the squared error loss function and general entropy loss function (shape parameter q = -0.5, 1.0). We also derive interval estimation such as the asymptotic confidence interval, the credible interval, and the highest posterior density interval. Finally, we compare the proposed estimators in the sense of the mean squared error through Monte Carlo simulation. The average length of 95% intervals and the corresponding coverage probability are also obtained.

Estimation of entropy of the inverse weibull distribution under generalized progressive hybrid censored data

  • Lee, Kyeongjun
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.3
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    • pp.659-668
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    • 2017
  • The inverse Weibull distribution (IWD) can be readily applied to a wide range of situations including applications in medicines, reliability and ecology. It is generally known that the lifetimes of test items may not be recorded exactly. In this paper, therefore, we consider the maximum likelihood estimation (MLE) and Bayes estimation of the entropy of a IWD under generalized progressive hybrid censoring (GPHC) scheme. It is observed that the MLE of the entropy cannot be obtained in closed form, so we have to solve two non-linear equations simultaneously. Further, the Bayes estimators for the entropy of IWD based on squared error loss function (SELF), precautionary loss function (PLF), and linex loss function (LLF) are derived. Since the Bayes estimators cannot be obtained in closed form, we derive the Bayes estimates by revoking the Tierney and Kadane approximate method. We carried out Monte Carlo simulations to compare the classical and Bayes estimators. In addition, two real data sets based on GPHC scheme have been also analysed for illustrative purposes.

Shape recovery and extraction the reflection properties of hybrid reflectance surface(II) (혼성 반사면의 반사 특성 추출 및 형상 복구(II))

  • 김태은;최종수
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.34S no.6
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    • pp.21-29
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    • 1997
  • In this paper, we propose a new approach for recovering 3-D shape and extracting the reflectance properties of surface from intensity images. Photometric stereo method(PSM) is genrally based on the direct illumination. In this paper, the reflectance function is derived by interoduceing the indirect diffuse illumination in PSM and then applied to hybrid reflectance model which consists of two components; the lambertian and the specular reflectance. Under the hybrid reflectance model and the indirect diffuse illumination circumstance, the reflectance properties of sample surface can be extracting by normal sampler and then 3-D shape of an object can be recovered based on extracting reflectance properties. This method is rapid because of using the reference table and simplifies the restriction condition about the reflectance function existing in prior studies. Th erecovery efficiency in our method is better than that in prior studies. Also, this method is applied to various types of surfaces by defining general reflectance function.

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Development of the Hybrid Vibration Isolator for Large Superprecision Stage (대형 초정밀 스테이지용 복합 아이솔레이터 개발)

  • Kim, Won-Kyum;Jung, Soon-Chul;Chang, Seung-Hwan;Lee, Jae-Eung;Shin, Dong-Su;Lee, Jae-Jung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.1404-1408
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    • 2006
  • In this paper, a hybrid-type vibration isolator which has air chamber(spring) and viscous damper in series is developed. The developed vibration isolator is designed to perform 3 following functions : spring function for normal operating conditions, damping function to reduce an impact for sudden move of upper beam, and finally leveling function. Based on the given natural frequency and damping factor, the design procedure is proposed. The performance of the developed isolator is tested by measuring stiffness and damping.

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Obtaining 3-dimensional shape of hybrid reflectance surfaces using indirect diffuse illumination (간접 확산 조명을 이용한 혼성반사 표면의 3차원 형상 취득)

  • 김태은;안호근;최종수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.2
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    • pp.301-312
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    • 1996
  • A new approach is presented for recovering the 3-D shape from shading image. Photometric Stereo Method (PSM) is generally based on the direct illumination. In this paper, the reflectance function is derived by introduceing the indirect diffuse illumination in PSM and then applied to hybrid reflectance model which consists fo two components; the Lambertian reflectance and the speclar reflectance. Under the hybrid reflectance model and the indirect diffuse illumination circumstances, the 3-D shape of object can be recovered from the suface normal vector extracted from the surface roughness, the surface reflectance ratio, and the intensity value of a pixel. This method is rapid because of using the reference table and simplifies the restriction condition about the reflectance function existing in prior studies. The recovery efficiency in our method is better than that in prior studies. Also, this method is applied to various types of surfaces by defining general reflectance function.

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Engineering Hybrid Proteins by Modular Recombination and Evolutionary Optimization (모듈성 단백질의 재설계 및 개량)

  • Lee, Seung-Goo;Rha, Eu-Gene;Ha, Jae-Seok;Lee, Jeong-Min;Kim, Sun-Hwa
    • Microbiology and Biotechnology Letters
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    • v.36 no.2
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    • pp.149-157
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    • 2008
  • Many proteins consist of distinctive domains that can act independently or cooperatively to achieve a unique function. As these domains evolve from a naturally existing repertoire of functional domains, this implies that domain organization is an intrinsic element involved in building the complex structure and function of proteins. Thus, identifying functional domains would appear to be critical to the elucidation of questions related to protein evolution, folding, and the engineering of hybrid proteins for tai- lored applications. However, the simple application of "Lego-like assembly" to the engineering of hybrid proteins is an oversimplification, as many hybrid constructs lack structural stability, usually due to unfavorable domain contacts. Thus, directed evolution, along with computational studies, may help to engineer hybrid proteins with improved physico-chemical properties. Accordingly, this paper introduces several approaches to functional hybrid protein engineering that potentially can be used to create modulators of gene transcription and cell signaling, and novel biosensors to analyze biological functions in vivo.

Fuzzy Relation-Based Fuzzy Neural-Networks Using a Hybrid Identification Algorithm

  • Park, Ho-Seung;Oh, Sung-Kwun
    • International Journal of Control, Automation, and Systems
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    • v.1 no.3
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    • pp.289-300
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    • 2003
  • In this paper, we introduce an identification method in Fuzzy Relation-based Fuzzy Neural Networks (FRFNN) through a hybrid identification algorithm. The proposed FRFNN modeling implement system structure and parameter identification in the efficient form of "If...., then... " statements, and exploit the theory of system optimization and fuzzy rules. The FRFNN modeling and identification environment realizes parameter identification through a synergistic usage of genetic optimization and complex search method. The hybrid identification algorithm is carried out by combining both genetic optimization and the improved complex method in order to guarantee both global optimization and local convergence. An aggregate objective function with a weighting factor is introduced to achieve a sound balance between approximation and generalization of the model. The proposed model is experimented with using two nonlinear data. The obtained experimental results reveal that the proposed networks exhibit high accuracy and generalization capabilities in comparison to other models.er models.

Estimation for the Rayleigh distribution based on Type I hybrid censored sample

  • Kwon, Byongwon;Lee, Kyeongjun;Cho, Youngseuk
    • Journal of the Korean Data and Information Science Society
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    • v.25 no.2
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    • pp.431-438
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    • 2014
  • Type I hybrid censoring scheme is the combination of the Type I and Type II censoring scheme introduced by Epstein (1954). Epstein considered a hybrid censoring sampling scheme in which the life testing experiment is terminated at a random time $T^*$ which is the time that happens rst among the following two; time of the kth unit is observed or time of the experiment length set in advance. The likelihood function of this scheme from the Rayleigh distribution cannot be solved in a explicit solution and thus we approximate the function by the Taylor series expansion. In this process, we propose four dierent methods of expansion skill.