• Title/Summary/Keyword: salient

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Analysis of Reactive Power Capability for Salient Synchronous Generators, and its Application to Primary Restorative Systems (돌극형 동기 발전기의 무효전력 공급 한계 해석 및 우선공급계통에의 적용)

  • Lee, H.J.;Park, S.M.
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.1
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    • pp.14-17
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    • 2007
  • Power system restoration following a massive blackout starts with re-energizing primary restorative transmission systems at first. The comparison of the TLCC(transmission line charging capacity) and the RPC(reactive power capability) of related black-start generator should be considered in this stage because overvoltage can be caused by self-excitation at the generator when the RPC is smaller than the TLCC. The RPC can be decided by two criteria. One is stator end core heating, and the other is steady state stability. RPC in steady state stability area has been found based on a synchronous reactance Xd. This paper presents RPC limit of salient pole machine which is different from that of non-salient pole machine in steady state stability area and shows derivation process about that.

Computing EMF of Salient Pole Rotor Type Single Phase SRM (돌극형 회전자 단상 SRM의 유도기전력 산출)

  • Kim, Jun-Ho;Lee, Eun-Woong;Oh, Young-Woong;Lee, Min-Myung
    • Proceedings of the KIEE Conference
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    • 2001.07b
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    • pp.868-870
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    • 2001
  • Salient pole rotor type single phase SRM(switched reluctance motor) can be use axial direction magnetic flux and radial direction magnetic flux at the same time. Then, it has higher energy density per unit volume and can be lessened the shaft length of motor or exciting magnetic force. Additionally, it's durability is good because it is simple structure and driving device. Prototype of Salient pole rotor type single phase SRM was fabricated by using parameters of three phase SRM and 3D FEM analysis. Also, driving device was fabricated for prototype. Speed and torque characteristic was confirmed through the experiments, and flux linkage, which is important parameter of SRM for generating torque, was measured. The induction emf was calculated by using ideal inductance graph and current graph. Calculated emf and measured emf was compared for confirming loss of prototype in this paper.

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Geometric Model Decimation Method for Salient Features (돌출된 특징을 위한 기하 모델 단순화 방법)

  • Kim, Soo-Kyun;An, Sung-Og
    • The Journal of Korean Association of Computer Education
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    • v.11 no.4
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    • pp.85-93
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    • 2008
  • This paper proposes a method for generating low-level geometric models with retaining salient features during decimation. Our method employs feature extraction technique for extracting feature lines defined via curvature derivatives on the model (we divide features into ridges and valleys). We add the extraction method to simplification technique (Feature Quadric Error Metric) for making coarse model with features. This paper clearly shows that experimental results have better quality and smaller geometric error than previous methods.

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A Study on the EMF harmonics of Salient Synchronous Generator (돌극 동기발전기의 역기전력 고조파 연구)

  • Park, Jeong-Tae;Kim, Chang-Wook;Kim, Keun-Ung
    • Proceedings of the KIEE Conference
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    • 2005.07b
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    • pp.1050-1052
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    • 2005
  • In this paper, air gap flux density is calculated by permeance model which can consider the effects of the stator slot and the salient pole shape of the salient synchronous generator. No load Electro-motive force(EMF) of the short-pitched and distributed stator winding is also calculated. Therefore, it's very convenient to calculate the THD of the no load EMF for the user's request, in the first design state.

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An Artificial Visual Attention Model based on Opponent Process Theory for Salient Region Segmentation (돌출영역 분할을 위한 대립과정이론 기반의 인공시각집중모델)

  • Jeong, Kiseon;Hong, Changpyo;Park, Dong Sun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.7
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    • pp.157-168
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    • 2014
  • We propose an novel artificial visual attention model that is capable of automatic detection and segmentation of saliency region on natural images in this paper. The proposed model is based on human visual perceptions in biological vision and contains there are main contributions. Firstly, we propose a novel framework of artificial visual attention model based on the opponent process theory using intensity and color features, and an entropy filter is designed to perceive salient regions considering the amount of information from intensity and color feature channels. The entropy filter is able to detect and segment salient regions in high segmentation accuracy and precision. Lastly, we also propose an adaptive combination method to generate a final saliency map. This method estimates scores about intensity and color conspicuous maps from each perception model and combines the conspicuous maps with weight derived from scores. In evaluation of saliency map by ROC analysis, the AUC of proposed model as 0.9256 approximately improved 15% whereas the AUC of previous state-of-the-art models as 0.7824. And in evaluation of salient region segmentation, the F-beta of proposed model as 0.7325 approximately improved 22% whereas the F-beta of previous state-of-the-art models.

Actuating Characteristics of Electrostatic Micro-motors

  • Kim, Young-Cheol;Kim, Byung-Ok
    • 연구논문집
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    • s.33
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    • pp.53-65
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    • 2003
  • Electrostatic micro-motors can be divided into three classes: (i) salient type side drive motor, (ii) radial gap type wobble motor, (iii) axial gap type wobble motor. The working mechanism, torque evaluation, fabrication, and operational characteristics of each micro motors are compared. It is proved that axial gap type wobble motor has the bigger generating torque than that of the other type. The gear ratio of wobble motors increases the driving torque at the cost of a decreasing angular speed and decreases the friction because of the rolling motion instead of sliding at the bearing. Techniques for characterizing micro-motors performance are presented.

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The Asymmetric Effects of Identity Salience on Judgement: The Role of Valence and Attribute Congruence

  • DaHee Han;Claire Heeryung Kim
    • Asia Marketing Journal
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    • v.25 no.2
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    • pp.84-98
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    • 2023
  • A salient identity influences individuals' judgment on products. The current research investigates why identity salience sometimes produces asymmetric effects on an individual's judgment such that a salient identity often influences judgment on identity-congruent products only or identity-incongruent products only. Across two experiments, this research proposes and shows that the valence of identity-incongruent and identity-congruent attributes determines the direction of the asymmetric identity salience effects. Specifically, when an attribute of an identity-incongruent product is positively- (negatively-) valenced, identity salience influences judgment through a decreased (increased) preference for the identity-incongruent (identity-congruent) product.

A Study on the salient points detection and object representation for object matching (물체 정합을 위한 특징점 추출 및 물체 표현에 관한 연구)

  • Park, Jeong-Min;Sohn, Kwang-Hoon;Huh, Young
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.6
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    • pp.101-108
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    • 1998
  • An efficient approach to recognize occluded objects is to detect a number of essential features on the boundary of the unknown shape. The salient points including corner points, tangential points and inflection points are detected by the relation of neighboring pixels of each pixel on the boundaries. Corner points are usually detected in the curvature function and tangential points and inflection points are detected by median filtering the curvature function to avoid the effect of quantization noise as corner points is not sufficient to represent an object with lines and arcs. Then, these salient points are used as features for object matching. Discrete Hopfield Neural Network is used for object matching. Experimental results show that the matching result using salient points is better than those of using corner points only when an object consists of lines and arcs.

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A Visual Image Perception of Clothing Colors, Color Combinations of Borean Traditional Dress for Woman(Part I) (복식색과 색조합의 이미지 지각(제1보) -여자 저고리, 치마를 중심으로 한 준실험 연구 -)

  • 이혜숙;김재숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.5
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    • pp.597-606
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    • 1998
  • The purposes of the study were 1) to evaluate the visual image of colored Korean traditional dress for woman 2) to analyze the colors and, color combinations effect on the image perception using gestalt theory. The research method was a quasi-experimental with a between subjects design. The experimental materials developed for the study were a set of stimuli and a response scale. The stimuli was consisted of 17 drawings of females wearing Korean tradinational dress, by using CAD simulation. A response scale consisted of semantic differential scales. The subjects were 1138 undergraduate students of Taejon city, Chungnam province and Chungbuk province. Their responses to the semantic differential scales were analyzed using factor analysis, one-way ANOVA, Duncan's multiple range test, 1-test. Results were as follows; 1) The image of the stimulus was consisted of the 4 different dimensions.(sociability, evaluation, visibility, attractiveness) 2) Clothing colors had significant effects on image perception of the evaluation dimension, visibility dimension and attractiveness dimension in the mono-color set. The blue showed the most positive image on the evaluation dimension, and the yellow and the gray showed negative image on the same dimension. The yellow showed the most salient image and the gray showed the least salient image on the visibility dimension. The red showed the most attractive image and the green showed the least attractive image on the attractiveness dimension. 3) In hi-color set stimulus, the perceived image was influenced by color combinations. The yellow blouse-the red skirt set showed the most sociable image on the sociability dimension. The blue blouse-the green skirt set showed the most positive image on the evaluation dimension. The yellow blouse-the red skirt set showed the most salient image and the blue blouse-the green skirt set showed the least salient image on the visibility dimension. And the red blouse-the yellow skirt set showed the most attractive image on the attractiveness dimension. On conclusion the visual image of Korean traditional dress wearer was affected by dress colors and color combinations.

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Assessment of U.S. Consumers' Underlying Beliefs about Local Food Purchase (미국 소비자들의 로컬 푸드 구매에 대한 내재된 신념에 관한 연구)

  • Shin, Yeon Ho;Hancer, Murat;Jung, Seung Eun;Kim, Dong Jin
    • Culinary science and hospitality research
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    • v.21 no.5
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    • pp.109-118
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    • 2015
  • The main purpose of this study is to get insight into the essential cognitive basis of local food purchase behavior based on Ajzen's (1991) theory of planned behavior. By asking open-ended questions using an online survey, participants' (n=163) salient behavioral, normative, and control beliefs in regard to local food purchase were assessed and analyzed. The most salient advantage was supporting local economy, followed by freshness, knowledge of where the food came from and how it was handled, environmental benefits, and health benefits. Assessing to consumers' normative beliefs found that local businesses, local farmers, family, local people, and friends were the most frequently mentioned individuals or groups who would approve consumers' local food purchasing. In contrast, the most salient barrier was inconvenient store location and time, followed by higher prices, limited availability and variety, and limited knowledge about where to buy local food.