• 제목/요약/키워드: Extreme Values

검색결과 406건 처리시간 0.033초

일사량에 따른 전압-전력 특성 (P-V Characteristics According to the Irradiation)

  • 박철웅;신현만;조재철;최용성;이경섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.2154_2155
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    • 2009
  • Development of renewable energy is promoted to achieve sustainability. So researchers are seeking and developing a new, clean, safe and renewable energy. However, solar energy is an extreme intermittent and inconstant energy source. In order to improve the photovoltaic system efficiency and utilize the solar energy more fully, and the DC power vary with the irradiation, it is necessary to study the characteristics of P-V according to the external factors. This paper presents the analysis of characteristics of P-V according to the irradiation. The results show that the DC power of the photovoltaic system are increased along with the increasing values of irradiation.

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P-V Characteristics of Photovoltaic According to the Irradiation

  • Lee, Ying;Choi, Yong-Sung;Zhang, You-Sai;Hwang, Jong-Sun;Lee, Kyung-Sup
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.2101_2102
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    • 2009
  • Solar energy has inestimable development potential. However, it is an extreme intermittent and inconstant energy source. The radiative energy output from the sun derives from a nuclear fusion reaction. So it is necessary to study the photovoltaic P-V characteristics according to the irradiation. The results show that the DC power of the photovoltaic system is increased along with the increasing values of irradiation and module.

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일사량에 따른 전압-전류 특성 (I-V Characteristics According to the Irradiation)

  • 황준원;정종철;김석곤;최용성;이경섭
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.2103_2104
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    • 2009
  • Solar, as an ideal renewable energy, has inexhaustible, clean and safe characteristics. However, solar energy is an extreme intermittent and inconstant energy source. In order to improve the photovoltaic system efficiency and utilize the solar energy more fully, and the DC current vary with the irradiation, it is necessary to study the characteristics of photovoltaic I-V according to the external factors. This paper presents the analysis of characteristics of photovoltaic I-V according to the irradiation. The results show that the DC current of the photovoltaic system are increased along with the increasing values of irradiation.

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Acoustic Monitoring of Rice Milling Process

  • Ikeda, Y.;Nishizu, T.;Akashi, S.;Satake, T.;Fukumori, T.;Mesaki, T.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2003년도 하계 학술대회 논문집
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    • pp.232-237
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    • 2003
  • Sound has been rated negatively in many industrial areas as the noise to be removed. In the agricultural process such as rice milling based on grinding the surface of the rice, however, it may be anticipated that the sound can contain the some information on the process. In this research, on the assumption that variation of the shape of the rice kernel during milling may bring the change in frequency characteristic of sound signal, we tried to investigate the relationship between the milling degree in the grinding test mill and the resonance and anti-resonance frequencies (the frequencies at which the sound power has the extreme values). (omitted)

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태양광 시스템에서 전압-전류 특성의 일사량 의존성 (Irradiation Dependance of I-V Characteristics of Photovoltaic System)

  • 박세준;황준원;최용성;이경섭
    • 전기학회논문지P
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    • 제58권4호
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    • pp.521-525
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    • 2009
  • Solar, as an ideal renewable energy, has inexhaustible, clean and safe characteristics. However, solar energy is an extreme intermittent and inconstant energy source. In order to improve the photovoltaic system efficiency and utilize the solar energy more fully, and the DC current vary with the irradiation, it is necessary to study the characteristics of photovoltaic I-V according to the external factors. This paper presents the analysis of characteristics of photovoltaic I-V according to the irradiation. The results show that the DC current of the photovoltaic system are increased along with the increasing values of irradiation.

Stochastic response spectra for an actively-controlled structure

  • Mochio, Takashi
    • Structural Engineering and Mechanics
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    • 제32권1호
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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.

Wind pressures on a large span canopy roof

  • Rizzo, Fabio;Sepe, Vincenzo;Ricciardelli, Francesco;Avossa, Alberto Maria
    • Wind and Structures
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    • 제30권3호
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    • pp.299-316
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    • 2020
  • Based on wind tunnel tests, this paper investigates the aerodynamic behavior of a large span canopy roof with elliptical plan and hyperbolic paraboloid shape. The statistics of pressure coefficients and the peak factor distributions are calculated for the top and bottom faces of the roof, and the Gaussian or non-Gaussian characteristics of the pressure time-histories in different areas of the roof are discussed. The cross-correlation of pressures at different positions on the roof, and between the top and bottom faces is also investigated. Combination factors are also evaluated to take into account the extreme values of net loads, relevant to the structural design of canopies.

수정된 엘만신경망을 이용한 외환 예측 (Predicting Exchange Rates with Modified Elman Network)

  • ;박범조
    • 지능정보연구
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    • 제3권1호
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    • pp.47-68
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    • 1997
  • This paper discusses a method of modified Elman network(1990) for nonlinear predictions and its a, pp.ication to forecasting daily exchange rate returns. The method consists of two stages that take advantages of both time domain filter and modified feedback networks. The first stage straightforwardly employs the filtering technique to remove extreme noise. In the second stage neural networks are designed to take the feedback from both hidden-layer units and the deviation of outputs from target values during learning. This combined feedback can be exploited to transfer unconsidered information on errors into the network system and, consequently, would improve predictions. The method a, pp.ars to dominate linear ARMA models and standard dynamic neural networks in one-step-ahead forecasting exchange rate returns.

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구간 결정값을 갖는 의사결정시스템의 양방향 퍼지 추론망 (A bidirectional fuzy inference network for interval valued decision making systems)

  • 전명근
    • 전자공학회논문지C
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    • 제34C권10호
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    • pp.98-105
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    • 1997
  • In this work, we proesent a bidirectional approximate reasoning method and fuzzy inference network for interval valued decision making systems. For this, we propose a new type of similarity measure between two fuzzy vectors based on the Ordered Weighted Averaging (OWA) operator. Since the proposed similarity measure has a structure to give the extreme values by choosing a suitable weighting vector of the OWA operator, it can render an interval valued similarity value. From this property, we derive a bidirectional approximate reasoning method based on the similarity measure and show its fuzzy inference network implementation for the decision making systems requiring the interval valued decisions.

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Absence of Physicality in Fashion -Focusing on the Deformation of the Body Parts-

  • Yim, Eun-Hyuk
    • International Journal of Costume and Fashion
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    • 제9권1호
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    • pp.26-33
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    • 2009
  • Clothes and human body are inseparably related. Aesthetic consciousness of the body determines the form of clothing, reflecting the time and culture as well as the individual and society. Clothes can even reorganize the meaning of the body, while transcending their instrumental functions of concealing, revealing, and deforming the body. Using �body�t o analyze the clothing form, my study develops a framework by which to classify the absence of physicality in fashion focusing on the deformation of the body parts. The absence of physicality denotes the break away from the idealized and standardized body for mass productions. It tends to experiment with extreme exaggeration in form refusing to subscribe to the traditional values that build on the balance and symmetry of the body, which opposes the sartorial convention and symbolism that results in the discord between signifiant and signifi? f clothing.