• 제목/요약/키워드: design wave

검색결과 3,251건 처리시간 0.033초

비선형파를 고려한 비대선의 선수선형설계에 관한 연구 (A Study on the Bow Hull Form Design of Full Ship Considering the Nonlinear Waves)

  • 유진원;이영길;최시영;최영찬;정광열;하윤진
    • 대한조선학회논문집
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    • 제47권5호
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    • pp.671-679
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    • 2010
  • This paper introduces a new hull form design method for the bow of a full ship, by actively applying the relation between the fore-body hull form and its wave resistance characteristics. For the hull form design, the Series 60($C_B=0.8$) hull is chosen as the parent ship, and Kracht's charts are used to determine the parameters of the bulbous bow in the early stages of hull form design. Several hull forms have been tested in order to obtain enough hull form variations with various bow shapes and design parameters in the search of the best design. In order to investigate the resistance characteristics of the designed hull forms, numerical simulations with corresponding model tests have been rigorously performed. For the numerical simulations, the Marker-density method is employed to track the nonlinear phenomena of the free surface(program IUBW). Model tests have also been performed to achieve an improved research performance using the designed hulls. Both numerical and experimental results show that the wave resistance of the hull forms can be effectively diminished if the bows are designed using the method introduced in this research. It is also expected that this research can facilitate better productivity in hull form design, especially at the preliminary design stage of a full ship type vessel.

A Study on Culture and Fashion of 'Ha-Han-Zu'

  • Yang, Wang;Lee, Sang-Rye
    • International Journal of Costume and Fashion
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    • 제6권1호
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    • pp.20-29
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    • 2006
  • Once people thought the phenomenon of 'Ha-Han' was only a vogue of young people pursuing oddity. However, when Korean TV series, Korean food, Korean movies and their music penetrated into our life and appeared on TV screens and fashionable magazines, all aspects influence of Korean wave finally arouse people's attention. 'Ha-Han-Zu' is a group of young people who pursue Korean popular culture even imitating their dressing, thoughts and behaviors. This article takes China the original place of Korean wave's popularity as focus, observes the reflection of Chinese to Korean popular culture and discusses the culture exchange phases of Korean wave as the center of popular culture. It can be more detailed that it bases on HOT wave from 1998 to 2004 and analyzes of popular TV series, observes reflects of 'Ha-Han-Zu' to Korean culture, discusses the acceptance to Korean popular culture and what kind of active reflection consumption giving to culture exchange.

충격파압에 의한 콘크리트 방파제의 거동 예측 (Response Prediction of Concrete Breakwater In Wave Impact Pressure)

  • 양종석;김성훈;김동완;경민수;김장호
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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    • pp.197-202
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    • 2002
  • The most common failure of breakwater comes from impact wave pressure generated by intense storms. This impact pressure is 10 folds greater than the pressure generated by normal waves. Therefore, the precise knowledge of magnitude of impact wave pressure applied on breakwater and its structural response is crucial for the economical and safe design. However, presently, a precise analysis of breakwater is restricted by insufficient and incorrect consideration of the effect of soil-structure Interaction. 3 major research areas included in this study are (1) theoretical analysis of impact wave pressure, (2) selection of breakwater structure model (3) soil-structure interaction analysis using limit analysis computer program. Based on this analysis, predicted response of concrete breakwater and probable failure location under wave impact pressure are determined.

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공기저항과 미기압파 저감을 위한 고속전철 전두부형상의 최적화설계 (Nose Shape Optimization of the High-speed Train to Reduce the Aerodynamic drag and Micro-pressure Wave)

  • 권혁빈;김유신;이동호;김문상
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.373-379
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    • 2001
  • When a train runs into a tunnel at high-speed, aerodynamic drag suddenly increases and the booming noise is generated at the exit of tunnel. The noise shape is very important to reduce the aerodynamic drag in tunnel as well as on open ground, and the micro-pressure wave that is a source of booming noise is dependent on nose shape, especially on area distribution. In this study, the nose shape has been optimized employing the response surface methodology and the axi-symmetric compressible Navier-Stokes equations. The optimal designs have been executed imposing various conditions of the aerodynamic drag and the micro-pressure wave on object functions. The results show that the multi-objective design was successful to decrease micro-pressure wave and aerodynamic drag of trains.

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과도 수파중의 복합실린더에 작용하는 쇄파력에 관한 연구 (Wave Force Acting on Cylinders in Transient Waves)

  • 조효제;구자삼;이상길
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2001년도 추계학술대회 논문집
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    • pp.220-226
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    • 2001
  • It is important to estimate exactly wave forces acting on various types of offshore structures under the severe environmental conditions in the ocean site. This paper presents an easy experimental method which deals with transient waves. The proposed scheme made it possible to generate breaking waves at any position in the wave tank by changing the maximum slope of the component waves. The theoretical and experimental methods were investigated by generating concentrated waves which acted on a single and multiple cylinders. The waves forces increased rapidly when the models encountered breaking waves. The theoretical results underestimates the forces due to breaking waves. Therefore, the effects due to breaking waves should be considered carefully in the design process of a structure under the influence of breaking waves.

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Design and Fabrication of the EM Wave Absorber with Excellent Characteristics for ETC System

  • Kim, Dong-Il;Choi, Dong-Soo;Choi, Dong-Han;Kim, Do-Yeol
    • Journal of electromagnetic engineering and science
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    • 제12권1호
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    • pp.20-25
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    • 2012
  • In this paper, the EM wave absorber for ETC system was designed and fabricated. We fabricated several samples in different composition ratios of flaked sendust and CPE(Chlorinated Polyethylene). Absorption abilities were simulated in accordance with different thicknesses of the prepared absorbers and changed complex relative permittivity and permeability according to composition ratio. The optimized mixing ratio of flaked sendust and CPE was found as 60 : 40 wt.% by experiments and simulation. Then the EM wave absorber was fabricated and tested using the simulated data. As a result, the developed EM wave absorber has the thickness of 2.75 mm and absorption ability was 22.5 dB in the case of normal incidence at 5.8 GHz. Therefore, it was confirmed that the newly developed absorber can be used for ETC system.

A Feasibility Study of Guided Wave Technique for Rail Monitoring

  • Rose, J.L.;Lee, C.M.;Cho, Y.
    • 비파괴검사학회지
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    • 제26권6호
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    • pp.411-416
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    • 2006
  • The critical subject of transverse crack detection in a rail head is treated in this paper. Conventional bulk wave ultrasonic techniques oftenfail because of shelling and other surface imperfections that shield the defects that lie below the shelling. A guided wave inspection technique is introduced here that can send ultrasonic energy along the rail under the shelling with a capability of finding the deleterious transverse crack defects. Dispersion curves are generated via a semi analytical finite element technique along with a hybrid guided wave finite element technique to explore the most suitable modes and frequencies for finding these defects. Sensor design and experimental feasibility experiments are also reported.

Wave Propagation 을 이용한 타이어 굽힘파 분석 (The analysis of tire's flexural characteristic using wave propagation)

  • 황성욱;한진혁;노국희;조춘택
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 추계학술대회논문집
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    • pp.1237-1240
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    • 2007
  • Tire noise is a major noise source at high speeds. One of the noise source is controlled by pattern and structure. Pattern noise is effected by the shape of tread. And the bending stiffness of tire is influenced to the resonance of tire‘s belt. But in high frequency region, FEA is not appropriated with application. So this paper discusses about wave propagation of tire. There has been much effort to verify the flexural wave velocity with structure design specification.

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