• Title/Summary/Keyword: ER 모델

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Model Synthesis and Performance analysis of an Engine Mount Using Electro-Rheological Fluids (전기유동유체를 이용한 엔진마운트의 모델구성과 성능해석)

  • 최영태;김기선;최승복;정재천;전영식
    • Transactions of the Korean Society of Automotive Engineers
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    • v.2 no.3
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    • pp.62-74
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    • 1994
  • This paper addresses on the model synthesis and performance analysis of an engine mount featuring electro-rheological(ER) fluids which undergo a phase change when subjected to electric fields. A novel type of ER fluid-filled engine mount is devised and its hydraulic model is constructed. An equivalent mechanical model is subsequently obtained from the governing equation of the hydraulic model. The model parameters associated with the ER fluids are distilled from experimental investigations on the Bingham properties of the fluids. The distilled data are then incorporated into the governing model to undertake feasible work through computer simulations,. It is shown that the proposed engine mount has an inherent capability of controlling both the damping force and the resonance frequency. Other superior performance characteristics accrued from the proposed methodology are also evaluated.

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A Star Schema Extraction Algorithm Using Connection Topologies of ER Diagrams (ER 도형의 연결 위상구조를 이용한 스타 스키마 추출 알고리즘)

  • 신성현;김진호
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.10c
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    • pp.136-138
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    • 2002
  • 관계형 OLAP 시스템에서는 다차원 분석에 사용될 데이터를 하나의 사실과 여러 개의 차원 테이블로 구성된 스타 스키마로 표현한다. 사실 테이블은 측정치의 속성을 포함하며, 차원 테이블들은 이러한 사실 테이블에서 중심으로 뻗어져 나온 형태로써, 측정치에 대한 정보를 제공한다. 방대한 크기의 OLTP 소스 데이타베이스로부터 사실과 차원 테이블로 구성된 스타 스키마 설계하기 위해서는 풍부한 경험과 많은 시간을 필요로 한다. 따라서 스타 스키마를 효과적으로 설계하기 위한 체계적인 설계 방법이 필요하다. 본 논문에서는 소스 데이터베이스들에 대한 개념적 모델인 ER 도형을 이용하여 여러 개의 사실 엔터티를 추출하는 알고리즘과 이를 통해 자동적으로 스타 스키마를 설계하는 알고리즘을 제시하였다. 스타 스키마가 하나의 사실 테이블에 여러 개의 차원 테이블이 M:1의 관계로 연결되었다는 성질을 활용하여, 이 방법에서는 EH 도형이 연결된 위상 구조를 이용하여 각 엔터티에 연결된 M:1 관계의 개수에 근거하여 사실과 차원을 추출하는 방법을 제시하였다. 본 논문에는 이러한 방법을 통해 데이터 웨어하우스의 스타 스키마들 자동적으로 쉽게 설계하여 소요되는 시간과 노력을 줄일 수 있도록 하였다.

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Bio-Gateway System Architecture for Integrating Heterogeneous Bio-Databases (이질형 바이오 데이터베이스 통합을 위한 게이트웨이 시스템)

  • Jung, Jin-Hee;Jung, Min-A
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.8
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    • pp.1828-1833
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    • 2005
  • The Integration of biological databases is critically important because of the interconnectedness of biological research. But it's not easy to integrate these databases for the different formats and designers in heterogeneous environments. So initial design is indispensable to integrate heterogeneous databases. In this paper, after we performed conceptual modeling on a popular nucleotide database, GenBank and a protein database, Swiss-Prot and integrated them by considering cross-reference. we also propose the integration system architecture called Bio-Gateway System, which can help users query closely linked information between two biological databases within one system differently from existing systems as well as query easily on condition that user knows fine condition for less effort.

A Design Methodology of Relational Database Based on Dataflow Diagram (자료흐름도에 기반한 관계형 데이터베이스의 설계방법)

  • 엄윤섭;권중장;정희석;김창동
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.615-618
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    • 2003
  • The design process of a relational database system consists of requirement analysis, conceptual design using ER diagram, logical design, and physical design. In logical design process, the conceptual schema is transformed to relational schema, and relational schema is normalized. This traditional design process is hard to applied in real database design process, since there is an ambiguity in conceptual design process. In this paper, we suggest a new design process, which provides more structural design steps by removing the conceptual design process. In new approach, we produce the data flow diagram by the structural methodology. From the attributes in the data store of data flow diagram, we construct relational table schema, and we normalize relational schema. Finally we produced table relationship diagram in order to figure out relationships between tables.

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A Study on SVM-Based Speaker Classification Using GMM-supervector (GMM-supervector를 사용한 SVM 기반 화자분류에 대한 연구)

  • Lee, Kyong-Rok
    • Journal of IKEEE
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    • v.24 no.4
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    • pp.1022-1027
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    • 2020
  • In this paper, SVM-based speaker classification is experimented with GMM-supervector. To create a speaker cluster, conventional speaker change detection is performed with the KL distance using the SNR-based weighting function. SVM-based speaker classification consists of two steps. In the first step, SVM-based classification between UBM and speaker models is performed, speaker information is indexed in each cluster, and then grouped by speaker. In the second step, the SVM-based classification between UBM and speaker models is performed by inputting the speaker cluster group. Linear and RBF are applied as kernel functions for SVM-based classification. As a result, in the first step, the case of applying the linear kernel showed better performance than RBF with 148 speaker clusters, MDR 0, FAR 47.3, and ER 50.7. The second step experiment result also showed the best performance with 109 speaker clusters, MDR 1.3, FAR 28.4, and ER 32.1 when the linear kernel was applied.

MAGNETO-OPTICAL KERR SPECTRA FOR AMORPHOUS RE-Co ALLOY FILMS (비정질 RE-Co 합금막의 자기광학 스펙트럼)

  • Y. J. Choe;S. Tsunashima;S. Uchiyama
    • Journal of the Korean Magnetics Society
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    • v.4 no.2
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    • pp.154-159
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    • 1994
  • The magneto-optical Kerr spectra(${\lambda}=250~700nm$) of amorphous RE-Co(RE=Ce, Nd, Pr, Gd, Tb, Er, Ho) are compared with those of Y-Co films. It has been found that the Kerr rotation of RE-Co is mainly due to Co in the long wavelength region, whereas at short wavelength Ce, Pr, Nd, and Gd contribute positively, and Tb, Ho, and Er contribute negatively to the Kerr rotation of RE-Co amorphous films. In the interesting energy region(1.5~5.0 eV), the magneto-optical contribution of Pr and Nd are thought to be related with $4f{\uparrow}->5d{\uparrow}$ interband transition, and the contribution of Ce and Gd might be concerned with d->p interband transition. The magneto-optical effect of Tb in the short wavelength region might be related with $4f{\downarrow}->5d{\downarrow}$ and/or $5d{\downarrow}->4f{\downarrow}$, and that of Ho and Er can be explained by $4f{\downarrow}->5d{\downarrow}$ magneto-optical interband transition.

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Gomisin A Ameliorates Endoplasmic Reticulum Stress-induced Hepatic Steatosis (Gomisin A의 비알코올성 지방간 보호효과)

  • Yun, Ye-Rang;Jung, Myeong Ho
    • Journal of Life Science
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    • v.27 no.2
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    • pp.233-240
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    • 2017
  • Previously, we have shown that Schisandra chinensis (Turcz.) Baill. (S. chinensis) has a protective effect against endoplasmic reticulum (ER) stress-induced hepatic steatosis. Gomisin A is a bioactive phytoestrogen derived from S. chinensis. In the present study, the in vitro and in vivo effects of gomisin A on ER stress and hepatic steatosis were investigated. We quantified the expression of markers of ER stress, including glucose regulated protein 78 (GRP78), C/EBP homolog protein (CHOP), and X-box-binding protein-1 (XBP-1), in HepG2 cells treated with tunicamycin or palmitate. Tunicamycin treatment in HepG2 cells induced the expression of markers of ER stress, including GRP78, CHOP, and XBP-1c. However, treatment with gomisin A reduced the expression of markers of ER stress. These inhibitory effects were also observed in palmitate-incubated HepG2 cells. The in vivo inhibitory effects of gomisin A were assessed in mice injected with tunicamycin or fed with a high fat diet (HFD). Gomisin A reduced the expression of markers of ER stress and decreased triglyceride levels in the livers of mice after tunicamycin injection or HFD feeding. Furthermore, gomisin A decreased the expression of inflammatory genes in palmitate-incubated HepG2 cells and the liver of HFD-fed obese mice. These results suggest that gomisin A inhibits ER stress and ameliorates hepatic steatosis induced by ER stress.

A Study on Applicability of Equivalent Continuum Flow Model in DFN Media (DFN 매질에 대한 등가연속체 유동모델의 적용 가능성 평가에 관한 연구)

  • Lee, Dahye;Um, Jeong-Gi
    • Tunnel and Underground Space
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    • v.27 no.5
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    • pp.303-311
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    • 2017
  • The correlation analysis between the results obtained from DFN flow model and equivalent continuum flow model were conducted on total of 72 DFN blocks having various fracture geometry and domain size. A strong linear relation seems to exist between the two approaches under condition that normalized relative error for continuum behavior (ER) is less than 0.2, and the results from both methods are found to almost identical. To explore the field applicability of equivalent continuum flow model in DFN media, a total of 48 numerical schemes related to inflow of underground circular openings were implemented under various DFN configurations. The equivalent continuum flow model in DFN media with a constant hydraulic aperture was evaluated as valid. However, as the anisotropy increases due to variation of the hydraulic aperture, the results are likely to be overestimated compare to the DFN flow model.

Attribute and is-a Relationship for Unification of Converting Rule on Database Schema (데이터베이스 스키마 전환규칙 통합을 위한 속성 및 is-a관계)

  • Kang, Byung-Young;Park, Chul-Jae
    • Proceedings of the Korea Information Processing Society Conference
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    • 2002.04a
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    • pp.117-120
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    • 2002
  • 본 논문에서는 객체지향 데이터베이스 스키마 전환 규칙 통합을 위한 속성, is-a 관계 및 예외처리를 정의하였다. 개념적모델(ER모델)에서 객체지향 스키마로 전환하는 규칙을 확장하여 개발하였으며 다중상속 문제나 예외처리와 같은 스키마의 변경에 대한 규칙도 제시한다. 객체지향 데이터베이스의 개념적모델을 전환하는 규칙을 정립함으로서 이미 생성된 정보를 활용할 수 있으며, 데이터베이스와 지식베이스를 결합하려는 시도에도 활용할 수 있다.

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Analysis of the Mean Uranium Valence of $U_{1-y}Er_{y}O_{2{\pm}x}$ Solid Solutions in terms of Lattice Parameter and Oneen Potential (격자상수 및 산소포텐샬에 의한 $U_{1-y}Er_{y}O_{2{\pm}x}$ 고용체의 평균우라늄원자가 분석)

  • Kim, Han-Soo;Sohn, Dong-Seong
    • Nuclear Engineering and Technology
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    • v.28 no.2
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    • pp.118-128
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    • 1996
  • The lattice parameters of stoichiometric $UO_2$ and $U_{1-y}Er_{y}O_2$ in the range of y=0.01 to y =0.33 were determined with use of X-ray diffraction data. Oxygen potentials have been measured by means of a thermogravimetric method in the range of 1200~$1500^{\circ}C$ and $10^{-14}$ $\leq$ $Po_2$ $\leq$ $10^{-3}$ for pure $UO_2$ and $U_{1-y}Er_{y}O_{2{\pm}x}$ solid solutions with y=0.02, y=0.06 and y=0.20, respectively. Their oxygen partial pressures were maintained by controlling $CO_2$/CO mixture atmosphere, and the $Po_2$ values corresponding to x of $U_{1-y}Er_{y}O_{2{\pm}x}$ solid solutions were measured with an electrolyte oxygen sensor. The lattice parameter decreases linearly with an increase in the erbium content. The change of the lattice parameter can be expressed in a linear equation of y as a($\AA$) =5.4695-0.220y for 0 $\leq$y$\leq$0.33. The experimental coefficient of y -0.220 in $U_{1-y}Er_{y}O_2$ was an intermediate value between the calculated values -0.273 and -0.156 in the case of $U^{5+}$ and $U^{6+}$, respectively. The (equation omitted) has been found to undergo abrupt increase in the range of -360 to -270 kJ/mole for y=0.06 and -320 to -220 H/mole for y=0.20, respectively, in the temperature range of 1200-$1500^{\circ}C$. (equation omitted) increases with erbium content, but the effect of the dopant for x =0.01 is less significant than that for stoichiometry. The oxygen potentials for $UO_2$ and $U_{0.98}Er_{0.02}O_{2+x}$ can be approximately represented by the $U^{5+}$/$U^{4+}$ model but those for y$\geq$ 0.06 in $U_{1-y}Er_{y}O_{2{\pm}x}$ solid solutions cannot be interpreted by the mean uranium valence model.

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