• Title/Summary/Keyword: ${\pi}$-domain

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An efficient Decision-Making using the extended Fuzzy AHP Method(EFAM) (확장된 Fuzzy AHP를 이용한 효율적인 의사결정)

  • Ryu, Kyung-Hyun;Pi, Su-Young
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.6
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    • pp.828-833
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    • 2009
  • WWW which is an applicable massive set of document on the Web is a thesaurus of various information for users. However, Search engines spend a lot of time to retrieve necessary information and to filter out unnecessary information for user. In this paper, we propose the EFAM(the Extended Fuzzy AHP Method) model to manage the Web resource efficiently, and to make a decision in the problem of specific domain definitely. The EFAM model is concerned with the emotion analysis based on the domain corpus information, and it composed with systematic common concept grids by the knowledge of multiple experts. Therefore, The proposed the EFAM model can extract the documents by considering on the emotion criteria in the semantic context that is extracted concept from the corpus of specific domain and confirms that our model provides more efficient decision-making through an experiment than the conventional methods such as AHP and Fuzzy AHP which describe as a hierarchical structure elements about decision-making based on the alternatives, evaluation criteria, subjective attribute weight and fuzzy relation between concept and object.

Novel Anti-Angiogenic and Anti-Tumour Activities of the N-Terminal Domain of NOEY2 via Binding to VEGFR-2 in Ovarian Cancer

  • Rho, Seung Bae;Lee, Keun Woo;Lee, Seung-Hoon;Byun, Hyun Jung;Kim, Boh-Ram;Lee, Chang Hoon
    • Biomolecules & Therapeutics
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    • v.29 no.5
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    • pp.506-518
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    • 2021
  • The imprinted tumour suppressor NOEY2 is downregulated in various cancer types, including ovarian cancers. Recent data suggest that NOEY2 plays an essential role in regulating the cell cycle, angiogenesis and autophagy in tumorigenesis. However, its detailed molecular function and mechanisms in ovarian tumours remain unclear. In this report, we initially demonstrated the inhibitory effect of NOEY2 on tumour growth by utilising a xenograft tumour model. NOEY2 attenuated the cell growth approximately fourfold and significantly reduced tumour vascularity. NOEY2 inhibited the phosphorylation of the signalling components downstream of phosphatidylinositol-3'-kinase (PI3K), including phosphoinositide-dependent protein kinase 1 (PDK-1), tuberous sclerosis complex 2 (TSC-2) and p70 ribosomal protein S6 kinase (p70S6K), during ovarian tumour progression via direct binding to vascular endothelial growth factor receptor-2 (VEGFR-2). Particularly, the N-terminal domain of NOEY2 (NOEY2-N) had a potent anti-angiogenic activity and dramatically downregulated VEGF and hypoxia-inducible factor-1α (HIF-1α), key regulators of angiogenesis. Since no X-ray or nuclear magnetic resonance structures is available for NOEY2, we constructed the three-dimensional structure of this protein via molecular modelling methods, such as homology modelling and molecular dynamic simulations. Thereby, Lys15 and Arg16 appeared as key residues in the N-terminal domain. We also found that NOEY2-N acts as a potent inhibitor of tumorigenesis and angiogenesis. These findings provide convincing evidence that NOEY2-N regulates endothelial cell function and angiogenesis by interrupting the VEGFR-2/PDK-1/GSK-3β signal transduction and thus strongly suggest that NOEY2-N might serve as a novel anti-tumour and anti-angiogenic agent against many diseases, including ovarian cancer.

Estimation of Flood Risk Index for the Nakdong River Watershed (낙동강 유역의 홍수위험지수 산정)

  • Song, Jae Ha;Kim, Sangdan;Park, Moo Jong;Choi, Hyun Il
    • Journal of Korea Water Resources Association
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    • v.46 no.1
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    • pp.35-45
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    • 2013
  • The aim of study is to present how to estimate and use the FRI (Flood Risk Index) for classifying area zones based on regional flooding risk in terms of the integrated flood risk management. To estimate the FRI at a spatial resolution of city/county/town units for the Nakdong River Watershed, the 17 representative flood indexing factors are carefully selected for the three flood indexes, such as PI (Pressure Index), SI (State Index), and RI (Response Index) under the P-S-R (Pressure-State-Response) classification system. Because flood indexing factors are measured at different scales and units, they are transformed into a common domain by the T-Score normalization technique. The entropy weight coefficient method is also applied to calculate the weight of flood indexing factors in order to reduce subjective judgement on the effect of weight coefficients. The three flood indexes of PI, SI, and RI are integrated for an overall value of the FRI to evaluate the flood risk of districts. To examine the practical application of the proposed FRI, the FRI results with/without the weight coefficients are compared with flooding zones of natural disaster risk areas officially announced in 2010. It is expected that the FRI ensured by full verification can make regional protection plans against flooding disasters with respect to causes and characteristics of past floods.

Properties of Nanocomposites Based on Polymer Blend Containing PVDF, Carbon Fiber and Carbon Nanotube (PVDF를 포함한 고분자 블렌드와 탄소섬유/탄소나노튜브를 이용한 복합재료의 특성)

  • Kim, Jeong Ho;Son, Kwonsang;Lee, Minho
    • Applied Chemistry for Engineering
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    • v.25 no.1
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    • pp.14-19
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    • 2014
  • Nanocomposites based on poly(methyl methacrylate) (PMMA)/poly(vinylidene fluoride) (PVDF) and poly(ethylene terephthalate) (PET)/(PVDF) blended with carbon fibers (CF) and carbon nanotube (CNT) were prepared by melt mixing in the twin screw extruder. Morphologies of the PMMA/PVDF/CF/CNT and PET/PVDF/CF/CNT nanocomposites were investigated using SEM. The aggregation of CNT was observed in PMMA/PVDF/CF/CNT nanocomposites while the good dispersion of CNT was shown in PET/PVDF/CF/CNT nanocomposites. In SEM image of PET/PVDF/CF/CNT nanocomposite, the CNT were mainly located at the PET domain of phase-separated PET/PVDF blend due to the ${\pi}-{\pi}$ interaction between the phenyl ring of PET and graphite sheet of the CNT's surface. In addition, a fairly good compatibility between PET/PVDF matrix and CF was shown in the SEM image. In the case of PET/PVDF nanocomposites blended with the co-addition of CF and CNT, the volume electrical resistivity decreased while no change was observed in PMMA/PVDF/CF/CNT composites. The degree of CNT dispersion in morphology results was consistent with the electrical conductivity results. From the DSC results, the crystallization temperature (Tc) of PET/PVDF/CF/CNT nanocomposites increased due to the co-addition of CF and CNTs acting as a nucleating agent. Flexural modulus of PET/PVDF/CF/CNT were sharply enhanced due to increasing the interaction between PET and CF.

Multi-loop PID Control Method of Brushless DC Motors via Convex Combination Method

  • Kim, Chang-Hyun
    • Journal of Electrical Engineering and Technology
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    • v.12 no.1
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    • pp.72-77
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    • 2017
  • This paper proposes the explicit tuning rule of multi-loop PID controller for brushless direct current motors to predict the system behaviors in time and frequency domains, using properties of the convex combination method. The convex set of the proposed controllers formulates the envelope to satisfy the performances in time and frequency domains. The final control parameters are determined by solving the convex optimization problem subject to the constraints which are represented as convex set of time domain performances. The effectiveness of the proposed control method is shown in the numerical simulation, in which controller tuning algorithm and dynamics of brushless DC motor are well taken into account.

Tuning-free Anti-windup Strategy for High Performance Induction Machine Drives (고성능 유도전동기 구동을 위한 자동 튜닝 Anti-windup 기법)

  • Seok Jul-Ki;Bae Sang-Gyu;Lee Dong-Choon
    • Proceedings of the KIPE Conference
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    • 2004.07a
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    • pp.312-315
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    • 2004
  • This paper presents a tuning-free conditional integration anti-windup strategy for induction machine with Proportional-Integral (PI) type speed controller. The on/off condition of integral action is determined by the frequency domain analysis of machine torque command without a prior knowledge of set-point changes. There are no tuning parameters to be selected by users for anti-windup scheme. In addition, the dynamic performance of the proposed scheme assures a desired tracking response curve with minimal oscillation and settling time even in the change of operating conditions. This algorithm is useful in many high performance induction machine applications not to allow the oscillation and overshoot of speed/torque responses. The main idea can be extended to general applications such as chemical processes and industrial robots.

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Modeling and Filter Design through Analysis of Conducted EMI in Switching Power Converters

  • Vimala, R.;Baskaran, K.;Aravind Britto, K.R.
    • Journal of Power Electronics
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    • v.12 no.4
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    • pp.632-642
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    • 2012
  • This paper presents a filter analysis of conducted Electro-Magnetic Interference (EMI) in switching power converters (SPC) based on noise impedances. The EMI characteristics of SPC can be analytically deduced from a circuit theoretical viewpoint. The analytical noise model is investigated to get a full understanding of the EMI mechanism. It is shown that with suitable and justified model, filters pertinent to EMI noise is investigated. The EMI noise is identified by time domain measurements associated with an isolated half-bridge ac-dc converter. Practical filters like LC filter, ${\pi}$ filter and complete EMI filters are investigated. The proposed analysis and results can provide a guideline for improving the effectiveness of filtering schemes in SPC. Experimental results are also included to verify the validity of the proposed method. The results obtained satisfy the Federal Communications Commission (FCC) class A and class B regulations.

On-line Optimal EMS Implementation for Distributed Power System

  • Choi, Wooin;Baek, Jong-Bok;Cho, Bo-Hyung
    • Proceedings of the KIPE Conference
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    • 2012.11a
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    • pp.33-34
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    • 2012
  • As the distributed power system with PV and ESS is highlighted to be one of the most prominent structure to replace the traditional electric power system, power flow scheduling is expected to bring better system efficiency. Optimal energy management system (EMS) where the power from PV and the grid is managed in time-domain using ESS needs an optimization process. In this paper, main optimization method is implemented using dynamic programming (DP). To overcome the drawback of DP in which ideal future information is required, prediction stage precedes every EMS execution. A simple auto-regressive moving-average (ARMA) forecasting followed by a PI-controller updates the prediction data. Assessment of the on-line optimal EMS scheme has been evaluated on several cases.

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Design and Implemention of Decision Model for Registration Fee Using the Fuzzy Reasoning (퍼지추론에 의한 등록금 결정 모델의 설계 및 구현)

  • Chung, Hong;Pi, Su-Young;Chung, Hwan-Mook
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1997.10a
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    • pp.97-101
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    • 1997
  • In recent years, there have been a number of applications of fuzzy logic in fuzzy reasoning system. The main objective of these applications is to approximate a decision making using the fuzzy reasoning system. This paper designs a fuzzy reasoning model for the decision making of registration fee at a private school, implements it applying for linguistic variables and fuzzy rules, and evaluates the practical availability of the model. The system accepts fuzzy rules, the type of membership functions, the domain of fuzzy sets and hedge, and fuzzifies the linguistic variables to generates fuzzy sets. The fuzzy sets generated are combined to constructs a solution fuzzy set. Finally, the system defuzzifies the solution fuzzy set to calculate a scalar value which is used for decision making.

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A Research on Developing the Fault Tolerant Control System using Restructurable Control Method (구조 변경 제어 방식을 이용한 고장 허용 제어 시스템 설계에 관한 연구)

  • Hong, Ho-Taek;Kim, Yong-Min;Park, Jae-Hong
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.10
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    • pp.1259-1263
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    • 1999
  • In this paper, a method to guarantee system continuity is developed, which can be applied to discontinuity problem in the time domain of restructurable control system. This method can be summarized as input alternation using weight change considering convergence speed of system mode. Input is changed from 'system continuity guarantee input,' which is defined as a input that minimizes the change of state variables, to 'alternative controller input,' which is selected by Neil's PI/EAM[3]. AIDC aircraft model is used for simulation. By showing the waveform of system input and state variable, we can sure that this method is effective for depression of system shock like jerk.

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