• Title/Summary/Keyword: loss variation

Search Result 1,226, Processing Time 0.029 seconds

Effect of Chromium Chloride on the Mechanical and Dielectric Properties of EPDM Rubber

  • Salem, M.A.;Khaled, M.A.;Hussein, A.M.;Elway, E.
    • Macromolecular Research
    • /
    • v.11 no.4
    • /
    • pp.256-259
    • /
    • 2003
  • Measurements of Young's modulus, dielectric loss and a.c. conductivity have been carried out on EPDM rubber samples loaded with different concentrations of $CrCl_3$ (0,2,4 and 6 phr). The values of Young's modulus was found to be linearly dependent on the $CrCl_3$ content. Variation of the dielectric loss with temperature showed that $CrCl_3$ may act as plasticizer. However, at higher frequencies the dielectric loss was found to be independent of frequency and the rubber samples may behave as non-polar dielectric. Investigations of the a.c conductivity suggested that the conduction in these rubber samples can be described by small polaron tunneling. In addition, conductivity was found to increase with $CrCl_3$ content.

Thermal characteristics variation of PDP in compliance with dielectric loss

  • Lee, Tae-Ho;Jung, Jae-Chul;Lee, Sang-Kuk;Kim, Joong-Kyun;Whang, Ki-Woong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.265-268
    • /
    • 2009
  • The discharge condition of Plasma display panel(PDP) changes as the display time increases. Imaginary part of permittivity of dielectric material which is related to dielectric loss has been often neglected because of relatively small value compare to that of the real part. The thermal characteristics of PDPs with two different dielectrics has been studied and compared.

  • PDF

A Study on Dielectric Properties of Printed Circuit Board Materials with Variation of Frequency and Temperature (온도 및 주파수 변화에 따른 프린트 배선기판의 유전특성 연구)

  • 박종성;김종헌;이준웅
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.10
    • /
    • pp.773-777
    • /
    • 1998
  • This paper presents the results of measured permittivity of PCB sheet material in the frequency range of 0.1 ~ 2[㎓] and temperature range of 25~ 85[>$^{\circ}C$]. Microstrip lines with different physical length are implemented to measure the attenuation and phase shift of the signals through these lines. The loss factor of glass-epoxy and teflon could by calculated with the measured dielectric constant and the attenuation. From the experiment, the glass-epoxy was more influenced by temperature and frequency than teflon. The average dielectric constants of glass-epoxy and teflon within the measured frequency range are 4.48 and 2.18, respectively.

  • PDF

2-D Finite Element Analysis of Brushless DC Motor Considering Eddy Current (와전류 손실을 고려한 브러시리스 DC 모터의 2차원 유한 요소 해석)

  • Choi, Tae-Sik;Chun, Yon-Do;Lee, Ju;Lim, Tae-Bin;Kim, Suk-Tae
    • Proceedings of the KIEE Conference
    • /
    • 1999.07a
    • /
    • pp.49-51
    • /
    • 1999
  • This paper presents an efficient 2D finite element analysis(FEA) for brushless DC motor (BLDCM) taking into account the eddy current and lamination effect of stator. In BLDCM, the dynamic characteristic analysis considering the eddy current and driving circuit is applied for the accurate prediction of motor performance in high speed because the eddy current loss is proportional of square of the driving frequency. According to the variation of lamination number, the characteristics of electro magnetic force, torque, and eddy current loss are analyzed. From the results, it is known that the effect of the lamination of stator on the eddy current loss is verified.

  • PDF

Tension Control Using On-Line Compensation of Friction Loss for Continuous Strip Processing Line (연속 공정 라인의 실시간 마찰손 보상을 통한 장력 제어 특성 개선)

  • Lee, Jeong-Uk;Choi, Chang-Ho;Song, Seung-Ho;Hyun, Dong-Seok
    • Proceedings of the KIEE Conference
    • /
    • 2000.07b
    • /
    • pp.1096-1098
    • /
    • 2000
  • This paper proposes a tension control to compensate friction loss using on-line friction torque observer for a continuous strip processing line. Friction loss of roller results in significant deviation of strip tension. accordingly it has an influence on the operation of other adjacent rolls. To avoid tension variation of the strip, a friction torque observer is designed in adjacent roll, which operates in speed control mode. The experimental results show improvement of tension control performance by the proposed friction compensation method.

  • PDF

Economic Tolerance Design of Quality Characteristics by the TAGUCHI's Loss Function (다구찌의 손실함수를 이용한 특성치의 경제적 허용차 설계)

  • 최문일;강창욱;황의철
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.14 no.24
    • /
    • pp.133-139
    • /
    • 1991
  • If the specifications of product. in general. art determined too wide. the precision of product becomes diminished. Otherwise it costs dearly to keep the precision. Therefore, It is realistic to consider various factors in determining specification of qualify characteristics TAGUCH Idefines quality of an object as "Quality is the loss that a product causes to society after being shipped. other than any losses caused by its intrinsic function". Particularly, to improve the performances of product TAGUCHI focuses his attention on the product design and process design which enable the functional characteristics of product to he robust to noises. In this paper, by the TAGUCHI's loss function, the characteristics which affect the variation of a product performance are classified into the scrappable characteristics and the reworkable characteristics when the target values of functional characteristics have been determined. And we will determine the tolerance of each characteristic which minimize the quality cost by the cost function which considers the economic factors and probability features of each characteristic.cteristic.

  • PDF

The Consideration for the Loss Characteristics accompanied by Variation of Inverter waveform in Induction Motor (인버터 파형 변화에 따른 유도전동기의 손실 특성 고찰)

  • Baek, Soo-Hyun;Youn, Shin-Yong;Kim, Seong-Cheol;Kim, Pill-Soo
    • Proceedings of the KIEE Conference
    • /
    • 1995.07a
    • /
    • pp.174-176
    • /
    • 1995
  • An additional consideration for using general Induction Motor are about copper loss by harmonic component of source, and increase of iron loss due to switching frequency in semiconductor devices, so that these losses come to be significant elements on design for motors used for variable V/F. In this paper, therefore, the effects of the losses are discussed, in the case the source is generated by square wave and PWM Inverter.

  • PDF

Deep Residual Networks for Single Image De-snowing (이미지의 눈제거를 위한 심층 Resnet)

  • Wan, Weiguo;Lee, Hyo Jong
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2019.05a
    • /
    • pp.525-528
    • /
    • 2019
  • Atmospheric particle removal is a challenging task and attacks wide interests in computer vision filed. In this paper, we proposed a single image snow removal framework based on deep residual networks. According to the fact that there are various snow sizes in a snow image, the inception module which consists of different filter kernels was adopted to extract multiple resolution features of the input snow image. Except the traditional mean square error loss, the perceptual loss and total variation loss were employed to generate more clean images. Experimental results on synthetic and realistic snow images indicated that the proposed method achieves superior performance in respect of visual perception and objective evaluation.

Comparative Analysis of Low-pass Microstrip Filter Performances for Two Different Dielectric Materials

  • Samah Khmailia;Abdelkader MAMI
    • International Journal of Computer Science & Network Security
    • /
    • v.24 no.7
    • /
    • pp.118-122
    • /
    • 2024
  • The dielectric material is a basic element which impacts considerably on a microstrip structure performances. This project demonstrates how filter performances such as gain, bandwidth, return loss and insertion loss change proportionally with substrate material variation. The RT/Duroid 5880 and the FR-4 are two dielectric materials proposed as substrates of a low pass microstrip filter. The design and simulation are done on ADS software. The transmission and reflection characteristics show that the RT/ Duroid 5880 as a dielectric substrate permits to obtain better performance as compared to the FR-4 substrate.

Application of ArcGIS-based Model Developed to Estimate Monthly Potential Soil Loss (월단위 토양유실가능성 추정을 위해 개발된 ArcGIS 기반의 모형 적용)

  • Yu, Na Young;Shin, Min Hwan;Kim, Jonggun;Park, Youn Shik
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.59 no.5
    • /
    • pp.109-126
    • /
    • 2017
  • Universal soil loss equation (USLE) is used to estimate soil loss solely or employed in any hydrologic models. Since soil erosion has been an issue in South Korea for decades, the Ministry of Environment enacted a law to regulate soil erosion in 2012, which is the Notification of topsoil erosion status. The notification is composed of preliminary and field investigations, the preliminary investigation suggests to use USLE and provides USLE factors. However, the USLE factors provided in the notification was prepared at least 10 years ago, therefore it is limited to reflect recent climate changes. Moreover the current yearly USLE approach does not provide an opportunity to consider seasonal variation of soil erosion in South Korea. A GIS-based model was therefore applied to evaluate the yearly USLE approach in the notification. The GIS-based model employs USLE to estimate soil loss, providing an opportunity to estimate monthly soil loss with monthly USLE factor databases. Soil loss was compared in five watersheds, which were Geumgang, Hangang, Nakdonggang, Seomjingang, and Yeongsangang watersheds. The minimum difference was found at Seomjingang watershed, the yearly potential soil loss were 40.15 Mg/ha/yr by the notification approach and 34.42 Mg/ha/yr by the GIS-based model using monthly approach. And, the maximum difference was found at Nakdonggang watershed, the yearly potential soil loss were 27.01 Mg/ha/yr by the notification approach and 10.67 Mg/ha/yr by the GIS-based model using monthly approach. As a part of the study result, it was found that the potential soil loss can be overestimated in the notification approach.