• Title/Summary/Keyword: width function

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A Study on the Estimation of the Fatigue Life Using the Stress Generated Models in the Steel Railroad Bridges (강철도교의 응력발생모형을 이용한 피로수명 추정에 관한 연구)

  • Yong, Hwan Sun;Kim, Seok Tae;Lee, Seong Soo
    • Journal of Korean Society of Steel Construction
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    • v.8 no.4 s.29
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    • pp.19-29
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    • 1996
  • In this paper, it is presumed that the stress time history was generated by simulation method and investigated compatibility in regard to the reappearance of stress time history. In this procedure, the identified frequency distribution of stress range of the steel railroad bridge varies with the rational values of cut off point and bar width. Thus, we show variable aspect of the equivalent stress range results from change of cut off point and bar width. In addition, we analyze the variable of RMC and RMS model due to the cut off point and bar width of the measured stress history which influencs the prediction of fatigue life in the steel railroad bridge. The simulated stress time history is carried out by the superposition method incorporating the vertical load with rotation moment obtained from the Hermition interpolation function, and compared with developing stress results from measured maxi mum stress. Through this study, we can estimate the remaining fatigue life from a safety point of view and comparative accuracy.

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Thinning of 2D and 3D Fractal Antenna Arrays with Bounded and Unbounded Fractal Distribution Functions for Celestial Communications

  • Ponnapalli, Venkata Aditya Sankar;Jayasree, Pappu Venkata Yasoda
    • ETRI Journal
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    • v.38 no.6
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    • pp.1135-1144
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    • 2016
  • Fractal antenna arrays are geometry-based thinned arrays having multiband applications. The major challenge of these arrays is their large number of elements at higher expansion factors. This article presents the thinning of fractal antenna arrays while maintaining an appropriate balance between the side lobe level and beam width by using various quantized fractal distribution functions. A 2D square fractal antenna array and 3DSierpinski gasket antenna array are considered in this article to validate the proposed distribution functions. Nearly one third of the antenna elements are thinned in each successive iteration except in the case of a one-count distribution function. The proposed technique can simplify practical implementation and exhibits better performance for various parameters such as the side lobe level, side lobe angle, and half power beam width than fully populated fractal antenna arrays.

Study on the Theoretical Analysis of Lateral Guiding in Stripe geometry DH Laser Diode (스트라입구조형 DH Laser Diode의 Lateral Guiding 해석에 관한 연구)

  • Kim, Eun-Su;Park, Yeong-Gyu;Yang, In-Eung
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.17 no.5
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    • pp.1-7
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    • 1980
  • In this paper, the theoretical analysis of lateral guiding in stripe geometry DH laser diode is performed. In the analysis, the carrier density profile is modeled as the function of stripe width and the beam width variations related to the stripe width are calculated using the perturbed mode theory. Finally the results of this paper are compared and analyzed with the Hakki's calculated data & kirkby's experimental data.

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STABLE AND ROBUST ℓp-CONSTRAINED COMPRESSIVE SENSING RECOVERY VIA ROBUST WIDTH PROPERTY

  • Yu, Jun;Zhou, Zhiyong
    • Journal of the Korean Mathematical Society
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    • v.56 no.3
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    • pp.689-701
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    • 2019
  • We study the recovery results of ${\ell}_p$-constrained compressive sensing (CS) with $p{\geq}1$ via robust width property and determine conditions on the number of measurements for standard Gaussian matrices under which the property holds with high probability. Our paper extends the existing results in Cahill and Mixon from ${\ell}_2$-constrained CS to ${\ell}_p$-constrained case with $p{\geq}1$ and complements the recovery analysis for robust CS with ${\ell}_p$ loss function.

Optimization of fairway design parameters: Systematic approach to manoeuvring safety

  • Gucma, Stanislaw;Zalewski, Pawel
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.129-145
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    • 2020
  • The article presents a systematic approach to design of marine navigation channels parameters resulting from manoeuvring and operational safety. Relations between the parameters of waterway system elements and the conditions of safe ship operation have been determined and the objective function of waterway parameters' optimization problems has been minimized with respect to variables of construction and operation costs. These costs have been functionally associated to variables of channel width at the bottom and fairway depth. The method of fairway's width computation at specified safe depth at the preliminary and detailed stages of waterway design has been proposed. The results of this method application have been illustrated with two examples: 1. The modernization of Szczecin-Swinoujscie fairway aimed at accepting vessels of 60,000 DWT capacity. 2. Construction of an approach channel leading to a newly built container terminal in Swinoujscie harbour (Poland), handling ocean-going container ships of 20,000 TEU capacity.

Properties of Triangle-Shaped Fuzzy Membership Function (삼각 퍼지 멤버쉽함수의 특성)

  • 이규택;이장규
    • Journal of the Korean Institute of Intelligent Systems
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    • v.5 no.1
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    • pp.15-20
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    • 1995
  • Fuzzy membership functions are some kinds of mapping function for the fuzzification and the defuzzification. Triangle-shaped fuzzy membership functions are widely used in fuzzy controller, for it is easy to implement. In these membership functions, it is known that narrower fuzzy sets permit finer control near the operating point than that far from the operating point. $Supp{\acute{o}}se$ we have a membership function with narrower triangle near zero and wider triangle far from zero. The membership function will make fine control when small input is given and rough control at large input. Therefore the performance of the controller with that membership function will be enhanced. This paper presents how the width of triangle base in the fuzzy membership function has influence on the output using geometrical approaches.

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EFFECT OF HARDNESS CHANGES AND MICROSTRUCTURAL DEGRADATION ON CREEP BEHAVIOR OF A Mod.9Cr-1Mo STEEL

  • PARK K. S.;CHUNG H. S.;LEE K. J.;JUNG Y. G.;KANG C. Y.;ENDO T.
    • International Journal of Automotive Technology
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    • v.6 no.1
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    • pp.45-52
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    • 2005
  • Interrupted creep tests for investigating the structural degradation during creep were conducted for a Mod.9Cr-1Mo steel in the range of stress from 71 to 167 MPa and temperature from 873 to 923 K. The change of hardness and tempered martensitic lath width was measured in grip and gauge parts of interrupted creep specimens. The lath structure was thermally stable in static conditions. However, it was not stable during creep, and the structural change was enhanced by creep strain. The relation between the change in lath width and creep strain was described quantitatively. The change in Vickers hardness was expressed by a single valued function of creep LCR(life consumption ratio). Based on the empirical relation between strain and lath width, a model was proposed to describe the relation between change in hardness and creep LCR. The comparison of the model with the empirical relation suggests that about 65% of hardness loss is due to the decrease of dislocation density accompanied by the movement of lath boundaries. The role of precipitates on subboundaries was discussed in connection with the abnormal subgrain growth appearing in low stress regime.

A Study on Development of Seam Tracker with Weaving Function (위빙기능을 가진 용접선 추적장치의 개발에 관한 연구)

  • Kim, Hyun-Soo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.13 no.4
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    • pp.113-117
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    • 2007
  • The study was performed on the development of system in which the bead width can be controlled. In order to control the bead width, we designed the automatic seam tracking device by attaching the probe type strain gauge sensor, motor driving slide and encoder to check the moving distance, and interface card connected MCU(80Cl96KC) upside the speed controllable carriage. Seam tracking experiments were done by changing the bead width. We compared and analyzed the sampling data which were obtained by output voltage of strain gauge sensor and rotary encoder pulse every 50ms.

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A study on Variation of Marking Effecting the Required Property Quantity & Market Efficiency in Development of Ready-Made Clothes (기성복 디자인의 개발에서 Marking에 따른 차이가 원자재 소요량과 Maker 효율에 미치는 영향에 관한 연구)

  • 김준범
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.1
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    • pp.120-127
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    • 1999
  • The purpose of the study is to mae experimental whether the required property quantity and marker efficiency has variation of marking based on theoretical background of marking using th function of computer marking system. To investigate that variation of marking effect the required property quantity and marker efficiency as the following is tried to solve giving separation to item width of property cutting line detail which is believed to influence the required property quantity and marker efficiency. How to make experiment as follows separating in order marker of 1082 styles of women's ready-made clothes of with basic design(jacket. pants. skirt, two-piece). Then the data were subjected to analysis of variance and Duncan's multiple range test. The result of this studying as follows 1. In marker of women's jacket and pants the required property quantity shows lower when it is each item than when it is two-pice,. 2. In marker of women's pants marker efficiency shows the highest level when width is 132cm and it shows the lowest level when width is 112cm. 3. In width 152cm of skirt marker it has cutting lines shows lower the required property quantity than it doesn't have. 4. In marker of women's pants it has details shows more high marker efficiency than it doesn't have.

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A Study on the Sleeve Cap Ease of Leather Garment (피혁 의류의 Sleeve Cap Ease 분량에 관한 연구)

  • 최보람;서미아
    • The Research Journal of the Costume Culture
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    • v.9 no.1
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    • pp.33-43
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    • 2001
  • In this study, both kinds of materials, that is, leather and woolen fabrics, which have similar thickness, have been adopted. To determine proper length of ease, not only sleeve cap height but also sleeve width has been adjusted mainly based on 5cm length of the ease, which follows maximum sleeve cap height, and then different length of ease, for example, 4cm, 3cm, 2cm and 1cm of ease, have been made. As a result, eighteen kinds in total of sleeves have been made: In other words, each nine kinds of both leather and woolen fabrics have different ease lengths. In addition, each sleeve has been inspected visually and functionally. Following conclusion has been gotten based on outcome of the study: 1. Proper ease length for manufacture of leather garment is said to be 1∼2 cm. As a result, ease length with higher sleeve cap height shall be 1∼2cm, while the length with lower sleeve cap height shall be 1cm or less. 2. Wider sleeve width has better function. Considering relations with sleeve cap height, sleeve width shall exceed +4cm of bicep line. 3. to satisfy a variety of those conditions while manufacturing leather garment, sleeve cap height, which is used for the manufacture of full dress and street wear garment, To lessen the ease length, body A.H shall be relatively loose under the arms, or pad shall be supplemented on the shoulder, so that the difference had better be lessened to solve such problems.

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