• Title/Summary/Keyword: Reflection Line

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A Study on the Automatic Fairing and Modeling System of Hull From (선형의 자동순정 및 모델링 시스템에 관한 연구)

  • 김동준
    • Journal of Ocean Engineering and Technology
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    • v.14 no.2
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    • pp.121-127
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    • 2000
  • In this paper a new technique of inverse fairing problem for ship hull is proposed. Recently Lu solved the inverse fairing problem for automobile's body that was made by one surface element. In this system however hull surface is constructed by Gregory's composite surface interpolation method. So reflection line at boundary position is used as a tool of solving inverse problem in surface fairing. But the results are not good. The new concepts of Normal vector line and Constrained reflection line are introduced as an alternative tool. Energy minimization method for Normal Vector Line curve net and the inverse method for Constrained Reflection Line by using optimization technique are examined And the final lines from this proposed surface fairing method shows good fairness.

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Efficient Algorithm for the Real-time Generation of Reflection Lines (자동차 스타일링을 위한 반사선의 실시간 생성 및 표현 알고리듬)

  • Gang, Ju-Yeop;Lee, Geon-U
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.1 s.173
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    • pp.173-181
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    • 2000
  • Depending upon the method of the surface generation and the quality of the boundary curves provided, the resulting surfaces may have global or local irregularities in many cases. Thus it would be necessary for the designer to evaluate the surface quality and to modify the surface. This capability is very important because the defect of the surface requires the rework of the dies that causes a big loss in cost and delivery time. To simulate the reflection line test in the actual production line, a faster generation algorithm is presented. Among., various surface interrogation methods using reflection lines, Blinn-Newell type of reflection mapping is applied to generate reflection lines on the trimmed NURBS surface. The generation of reflection lines is formulated as a surface-plane intersection problem, and solved by surface-contouring techniques. In addition, a modified reflection map is proposed to eliminate the discontinuity of reflection lines due to the configuration of the reflection map. A fast reflection line algorithm is developed utilizing an efficient traced contouring technique, and proved to be well suited for real-time quality-assessment task.

Efficient generation of reflection lines to evaluate car body surfaces (자동차 외형설계곡면의 검사를 위한 효율적인 반사선의 생성)

  • 최인진;이건우
    • Korean Journal of Computational Design and Engineering
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    • v.2 no.3
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    • pp.133-141
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    • 1997
  • In the process of car body design, various surfaces are generated from the given boundary curves. Depending upon the method of the surface generation and the quality of the boundary curves provided, the resulting surfaces may have global or local irregularities in many cases. Thus it would be necessary for the designer to evaluate the surface quality and to modify the surface or to use the different generation method based on the evaluation results. This capability is very important because the defect of the surface quality detected in the production stage will require the rework of the dies and will cause a big loss in cost and time. A method of surface interrogation using reflection line is introduced. In this paper, We applied reflection mapping to generate reflection lines on the trimmed NURBS surface. Since reflection lines are obtained from reflection mapping that uses simple and physically acceptable mapping algorithm, they can be efficiently used to simulate the reflection test on the real part in the production line.

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An effects of the Pulse Distortion due to Dispersion and Reflection on Tapered Microstrip Line (데이퍼형 마이크로 스트립 선로에서 분산과 반사가 펄스의 왜곡에 미치는 영향)

  • 김기래
    • Proceedings of the IEEK Conference
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    • 2000.06a
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    • pp.271-274
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    • 2000
  • In this paper, the distortion of an electrical pulse with rise/fall time resulting from dispersion and reflection as it propagates along a tapered microstrip line is investigated, and the delay time and distortion rate with respect to input and load impedances are analyzed on triangular and exponential tapered lines and analyzed the influence of the reflection and frequency dispersion on the distorted voltage wave in the tapered lines. The observed overshoot in front of the distorted wave is caused due to the frequency dispersion and the sustained tail of that comes from the reflection in the tapered line.

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Enhancement of Seismic Stacking Energy with Crossdip Correction for Crooked Survey Lines

  • Kim, Ji Soo;Lee, Sun Jung;Seo, Yong Seok;Ju, Hyeon Tae
    • The Journal of Engineering Geology
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    • v.24 no.2
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    • pp.171-178
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    • 2014
  • In seismic reflection data processing, the crossdip correction effectively focuses the stacking energy near the sharp bends of a crooked survey line. Additionally, approximate 3-D information on the reflector (e.g., true crossdip angle and lateral continuity) are locally investigated as a by-product of the crossdip correction procedure. Improvement of the signal-to-noise ratio and estimation of reflector crossdip attitude are tested, in terms of both common midpoint bin direction and processing-line type, using synthetic seismic reflection data. To effectively image the reflection energy near bends in seismic survey lines, straight-line binning is preferred to slalom-line binning.

Analysis on Signal Flow Graph of Slotted LIne (Slotted Line의 Signal Flow Graph 해석)

  • 박기수
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.6 no.3
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    • pp.8-11
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    • 1969
  • In the precision measurement of the voltage standing wave ratio (VSWR) or reflection coefficient by means of the slotted line technique, one of the important factors is the maximum error due to the discontinuities and multi-reflection in the slotted line. Particularly, this error becomes a critical factor when the VSWR or the reflection coefficient to be measured is very small. In this paper, the exact expression of this error is obtained by means of the Signal flow graph method.

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Power Reflection and Transmission Coefficients for Meander-Line Polarizers with a Chiral Slab

  • Delihacioglu, Kemal;Uckun, Savas
    • ETRI Journal
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    • v.25 no.1
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    • pp.41-48
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    • 2003
  • This paper presents a theoretical investigation of power reflection and transmission coefficients for a meander-line polarizer placed periodically on a chiral slab. It is assumed that a linearly polarized transverse magnetic wave is incident on a chiral slab from the air region. In the analysis, we derive the electric and magnetic fields in the modal form in the air and chiral regions. We obtain power reflection and transmission coefficients in a straightforward manner after matching the tangential components of the electric and magnetic fields at the boundaries. We present numerical results for the power reflection and transmission coefficients versus frequency and incident angle for different values of the chirality admittance. A meander-line polarizer placed on a dielectric slab can convert a linearly polarized wave to a circularly polarized wave. The design parameters for a meander-line polarizer are the dimensions of the meander-line and the values of the dielectric slab. Replacing a dielectric slab with a chiral slab introduces a new independent parameter which controls the wave polarization.

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Efficient Algorithm for Real-time Generation of Reflection Lines

  • Kim, Tae-wan;Juyup Kang;Lee, Kunwoo;Park, Sangkun
    • Journal of Mechanical Science and Technology
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    • v.15 no.2
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    • pp.160-171
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    • 2001
  • Depending upon the method of the surface generation and the quality of the designed boundary curves, the resulting surfaces may have global or local irregularities in many cases. Thus, it would be necessary for the designer to evaluate the surface quality and to modify the surface. This is very important because the defect of the surface causes the rework of the dies, increasing cost and delivery time significantly. To simulate the reflection line test in the actual production line, a faster algorithm for generating reflection lines is presented. In this paper, among various surface interrogation methods using reflection lines, Blinn-Newell type of reflection mapping is applied to generate the reflection lines on the trimmed NURBS surfaces. The derivation of reflection lines is formulated as a surface-plane intersection problem (Jung 1994) and is solved by surface-contouring techniques. Also, for eliminating the discontinuity of reflection lines due to the configuration of reflection map, a modified reflection map is proposed. An efficient traced contouring technique is utilized for the computational efficiency and proves to be well suited for the real-time quality-assessment task.

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Earth Reflection Effect Analysis in the Environment of Line Source Induction (전력선 유도 환경에서의 지면 반사계 영향 분석)

  • Lee, Sangmu
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.4
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    • pp.26-32
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    • 2013
  • The earth reflection effect on the induced voltage by line source such as power line occurring induction inteference is analyzed to scrutinize how much it would reduce the induced voltage. Using hankel transformation including bessel function, directly calculation formulae for extracting a refelction coefficient is a most important technical application in this paper since the reflection coefficient on the earth cannot be deduced by a general coefficient calculation formulae according to a plain wave. The electric field is utilized to transform the electromagnetic field into an induced voltage. The composed efficiency to a source induction voltage by an earth reflection is about a range of 60~70% for the axis constellation of each object like observation point, source position and other material parameters.

Design of Planar Microwave Bandstop Filters by Control of Wave Propagation on Nonuniform Transmission Line

  • Park, Eui-Joon
    • Journal of Electrical Engineering and information Science
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    • v.2 no.5
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    • pp.114-120
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    • 1997
  • A design method is newly presented for the creation of planar type filters which shapes will be nonuniform transmission line with continuously varying characteristic impedances. Those filters yield frequency characteristics of the bandstop filter in transmission, and have not nay discontinuities. The design is achieved by the control of wave propagation in view to both reflection an transmission properties on the dispersive nonuniform line within the desired frequency band. The developed algorithm is based on optimized perturbations of inherent nulls of lobes from the solution of first-order nonlinear differential equation for reflection coefficients of the nonuniform line, and an appropriate distribution of reflection coefficient which affects to filter length and bandwidth. Practical measurements for designed wideband microstrip and stop filter show very good agreement with theoretical results.

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