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A Study On Wear Pattern of Wheel Flange for Urban Railway Vehicle (도시철도 차량 차륜 플랜지의 마모패턴에 관한 연구)

  • Noh, Hang-Nak;Maeng, Hee-Young;Kwon, Seok-Jin
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.71-77
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    • 2007
  • The surface of railway wheel tread in wheel-rail system can not be free from wear because of various circumstance such as railway condition, maintenance condition, weather condition, characteristics of wheel surface's geometrical shape, and vehicle suspension's structural characteristics etc. Therefore, the research on wear reduction and maintenance method are very important to ensure the safety of railway vehicle, to improve car comfort and to decrease maintenance cost. In this study, the wear rates of railway wheel have been periodically measured in terms of the running distance of Electrical Multiple Unit which have been currently operated and the microstructure transformation of wheel tread using replication method have been performed. The results show that the relations between the flange wear and tread microstructure are depended on running distance and it will supply basic data on wheel maintenance.

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Wavelet identification for the abnormal seismic wave component of rock burst

  • Yunliang Tan;Wei Yan;Tongbin Zhao
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.437-440
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    • 2003
  • As we know, roof is composed of heterogeneous rock. When roof fractures, a large amount of energy would be released in the form of seismic wave. How to identify the abnormal signal of seismic wave is a much difficult problem, there are many methods used usually, such as Fourier Transformation, filter technique etc., but abnormal signal can't be recognized accurately. In this paper, multi-resolution wavelet technique is used to identify the first and second variation point, based on the Lipschitz $\alpha$. A living example analysis shows, multi-resolution wavelet technique can identify the abnormal signal of seismic wave effectively in different scale, and the omen of roof fall can be grasped in order to forecast the roof fall accurately. It provides a new idea for the predication of catastrophe on rock mechanics and engineering.

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Wavelet-Based Face Recognition by Divided Area (웨이브렛을 이용한 공간적 영역분할에 의한 얼굴 인식)

  • 이성록;이상효;조창호;조도현;이상철
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2307-2310
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    • 2003
  • In this paper, a method for face recognition based on the wavelet packet decomposition is proposed. In the proposed method, the input image is decomposed by the 2-level wavelet packet transformation and then the face areas are defined by the Integral Projection technique applied to each of the 1-level subband images, HL and LH. After the defined face areas are divided into three areas, called top, bottom, and border, the mean and the variance of the three areas of the approximation image are computed, and the variance of the single predetermined face area for the rest of 15 detail images, from which the feature vectors of statistical measure are extracted. In this paper we use the wavelet packet decomposition, a generalization of the classical wavelet decomposition, to obtain its richer signal analysis features such as discontinuity in higher derivatives, self-similarity, etc. And we have shown that even with very simple statistical features such as mean values and variance we can make an excellent basis for face classification, if an appropriate probability distance is used.

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SYMMETRY REDUCTIONS, VARIABLE TRANSFORMATIONS AND EXACT SOLUTIONS TO THE SECOND-ORDER PDES

  • Liu, Hanze;Liu, Lei
    • Journal of applied mathematics & informatics
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    • v.29 no.3_4
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    • pp.563-572
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    • 2011
  • In this paper, the Lie symmetry analysis is performed on the three mixed second-order PDEs, which arise in fluid dynamics, nonlinear wave theory and plasma physics, etc. The symmetries and similarity reductions of the equations are obtained, and the exact solutions to the equations are investigated by the dynamical system and power series methods. Then, the exact solutions to the general types of PDEs are considered through a variable transformation. At last, the symmetry and integration method is employed for reducing the nonlinear ODEs.

The study on the Paeoniae Radix Alba's efficacy in "Sanghanron(傷寒論)" prescription ("상한론(傷寒論)" 처방(處方) 속의 작약(芍藥) 효능(效能)에 대한 연구(硏究))

  • Bang, Jung-Kyun
    • Journal of Korean Medical classics
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    • v.23 no.1
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    • pp.47-58
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    • 2010
  • "Sanghanron(傷寒論)" can be approached through the understanding of the formulas. It is very important to correlate the efficacy of drugs and pathogenesis of syndrome. In this sense, the author examines the Paeoniae Radix Alba's efficacy. The Paeoniae Radix Alba[芍藥] used in Gyejitang(桂枝湯), Galgeuntang(葛根湯), Sogeonjungtang (小建中湯), Jagyakgamchotang(芍藥甘草湯) all have a similar effect. The Paeoniae Radix Alba supplies the tendon and blood meridian with bodily fluids, so it treats the stiffness and pain of the head and neck[頭項强痛], stiffness of the neck and back[項背强几几] and acute pain in the abdomen[腹中急痛] etc. Meanwhile, the Paeoniae Radix Alba treats difficulty in urination. It moistens the path to the excretion of urine included among drugs which increase digestion and transformation.

A Study on the Magnetic Levitation Technology for Iron Plate Conveyance (강판운송을 위한 자기부상기술에 관한 연구)

  • 조경재;차인수;이권현
    • Proceedings of the KIPE Conference
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    • 1998.07a
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    • pp.95-98
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    • 1998
  • Applying the magnetically levitated transportation system, which is noncontact bearing system, to solve the problems such as transformation of original form or flaw of iron plate caused by transportation of thin iron plate which required high quality as body of motor vehicle, materials of electronic devices etc.. Magnetic saturation phenomena caused by thickness of iron plate and gap size between magnets. In case of iron plate, the vibration mode will be considered since vibration occurs during transportation. In order to solve the problems caused by vibration, choose the levitation system method using numbers of magnet, magnetic saturation for thickness and length of iron plate with parameters in location and gap of magnet. In this paper, we will suggest the whole design technique of magnetically levitated transportation system, namely method of magnetic attraction and transportation system

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Study on a Prediction of Noise Attenuation Performance of Automotive Mufflers (자동차 소음기의 소음성능 예측에 관한 연구)

  • 양기영;황원걸;기창두
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1994.10a
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    • pp.389-394
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    • 1994
  • The lattice filter formed transfer function has the advantage of computer simulation in the analysis of muffler. The transfer function is derived by using z-transformation for perforated elements in through-flow, cross-flow and reverse-flow type. A computer program for the prediction of the performance of automotive mufflers is developed using the transfer functions for uniform tube, open termination, expansion element, perforated elements, etc. The analytical results are verified by comparing with the experimental results for the transmission loss of a muffer. The effect of geometric configuration change of the muffler was invesigated in order to improve the performance of noise attenuation.

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The Residential Space Transformations according to the Introduction of Current Housing Life of Rural Traditional Houses in Taebaek Mountainous Regions (태백산간지역 농촌재래주택의 현대적 주생활 도입에 따른 주거공간의 변화)

  • Choi, Jang Soon
    • Journal of the Korean Institute of Rural Architecture
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    • v.15 no.3
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    • pp.33-40
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    • 2013
  • The rural traditional houses in Taebaek mountainous regions play important roles in figuring out values and social aspects of past time including housing life. But due to the introduction of convenient facilities in the current housing life style after industrialized society, many transformations have been taken place even to exist rural traditional folk houses such as installation of new equipment and furniture, the arrangement and function change of rooms, expansion of residential area and etc. So this study aims to secure basic data to prepare installation standard of the convenient facilities as examining convenience facility installation status of the cultural asset designated as rural traditional house, and to identify the meaning and usage of major room of rural traditional houses in order to prepare the proper balances between its original form preservation and residents' convenience living.

A Study of Improving Stability of a System with Perturbed Controller (섭동이 있는 제어기를 갖는 시스템의 안정도 향상에 관한 연구)

  • Cha, Young-Ho;Chung, Tea-Jin;Chung, Chan-Soo
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.466-468
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    • 1998
  • This paper designs a robust controller with improved stability of a system. Robust control theory has been developed by many researchers. The controller derived in that using robust control theory has an assumption that it will be exactly implementation. But, It is very hard because of truncation errors, D-A, A-D transformation, and finite resolution, etc. Such perturbations would make problems in the stability of the system. Recently, Keel's paper presents some examples which shows controllers based on the robust controller design method are very fragile on its own perturbation. In this paper, we try to improve the stability of the closed-loop system in which there exist perturbation in the plant as well as in the controller. The results shows that the stability is improved and the performance is still satisfied.

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Factors for Shopping Malls to be Successful in Delhi Ncr (India)

  • Mullick, N.H.
    • Asia-Pacific Journal of Business
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    • v.4 no.1
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    • pp.25-30
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    • 2013
  • Today a consumer is confused and he looks only for values in relation to the prices spent by him/her in the buying process. He/She relates value in terms product pricing, brand value, his experiences etc. This therefore gives a vast scope for organized retailing that can make products available as per the aspirations of the consumer. For these organized retailers, Shopping Malls are acting as a catalyst and helping them to enhance their growth all over the country. They are providing them the required infrastructure and also helping them to achieve a faster growth. The present study is therefore done visualizing the opportunities available in the Indian market and the issues faced by the mushrooming of Malls in Indian metropolitan cities making their survival difficult due to cut-throat competition. This is also resulting in poor occupation and is not able to find neither the right rentals nor the footfalls.

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