• Title/Summary/Keyword: Weight Method

Search Result 9,524, Processing Time 0.035 seconds

Minimum Weight Design of Transverse Frames of Oil Tankers by Generalized Slope Deflection Method (일반화 경사처짐법에 의한 유조선 횡강도 부재의 최소 중량 설계)

  • Chang-Doo Jang;Seung-Soo Na
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.33 no.3
    • /
    • pp.103-111
    • /
    • 1996
  • A generalized slope deflection method has already been developed by the authors from the existing one, and applied to the 3-dimensional structural analysis of tankers idealized as frame models to verify the effectiveness of the method from the analysis viewpoint. In this study, a minimum hull weight design program of tankers is developed to verify the effectiveness of the method from the design viewpoint by the combination of generalized slope deflection method and optimization method considering discrete design variables. By this program, it is possible to determine the scantling of each member of actual tankers that give minimum weight under given constraints. Also, a considerable weight saving has been found compared with existing ship.

  • PDF

Stress Analysis of Linear Elastic Solid Problems by using Enhanced Meshfree Method based on Fast Derivatives Approximation (고속 도함수 근사화에 의해 개선된 무요소법을 이용한 선형탄성 고체문제의 응력해석)

  • 이상호;김효진;윤영철
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2002.10a
    • /
    • pp.583-590
    • /
    • 2002
  • Point collocation method based on the fast derivatives approximation of meshfree shape function is applied to solid mechanics in this study. Enhanced meshfree approximation with approximated derivative of shape function is reviewed, and formulation of linear elastic solid mechanics by point collocation method is presented. It implies that governing equation of solid mechanics with strong form is directly formulated without no numerical integration cells or grid. The regularity of weight function is not required due to a use of approximated derivative, so we propose the exponential type weight function that is discontinuous in first derivative. The convergence and stability of the proposed method is verified by passing the generalized patch test. Also, the efficiency and applicability of the proposed method in solid mechanics is verified by solving types of solid problems. Numerical results show that not only a use of proposed weight function leads lower error and higher convergence rate than that of the conventional weight functions, but also the improved collocation method with derivative approximation enables to compute the derivatives of shape function very fast and accurately enough to replace the classical direct derivative calculation.

  • PDF

Standardization of Impact Test Methods of Non-bearing Lightweight Wall for Building (건축용 비내력 경량벽체의 내충격성 시험방법의 표준화)

  • Kim, Ki-Jun;Choi, Soo-Kyung
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2015.05a
    • /
    • pp.181-182
    • /
    • 2015
  • The use of non-bearing light weight wall has increased recently due to the increase of high-rise buildings and supply of long-life housing. Light weight wall has advantages such as reducing the self-weight of the building, convenience in installation, and shortening construction period, however, must have a sufficient strength to external force. This study standardized the impact resistance test method for light weight walls by using the actual impact load obtained through load analysis test in previous studies. The impact resistance test method was divided into the test method that uses soft body and the one that uses hard body. The size of specimen was set up as height 2.4m and width 3.0m. The size and shape of the body followed those used in BS 5234-2 and so on for the compatibility with the test method used overseas. The judgment criteria for impact resistance based on test results were not defined uniformly as the assessment of functional damage can vary depending on the type of material, structural method, purpose of wall, and so on even when the same impact load was applied.

  • PDF

A Study on the Molding Process of an Optical Communication Aspherical Glass Lens Using the Weight Molding Method (광통신용 비구면 글라스 렌즈 자중성형 공정 연구)

  • Ryu, Sang;Roh, Kyung Hwan;Choi, Kwang Hyeon;Kim, Won Guk;Lee, Won Kyung;Kim, Do Hee;Yang, Kuk Hyeon
    • Ceramist
    • /
    • v.21 no.4
    • /
    • pp.427-432
    • /
    • 2018
  • In this study, the aspherical lens for optical communications produced not with an one-step pneumatic type of external pressurization system (existed GMP process) but a constant weight of self-loaded mold put up to upper core. So the lens is molding with self-loaded weight molding and it calls Weight Molding process. In self-loaded molding process, we measured changes of center thickness molding lenses with each variable molding temperatures and time to find the effect of center of lens thickness to search key factors. As experimental results, the center thickness reach to targeted lenses step time value was changed drastically and it depends by molding temperature. If the molding temperature gets higher, the targeted lens that is reaching to the center thickness step time value was decreased. To find the effect of life improvement on mold core by imposing the self-loaded molding process we molded with GMP(Glass molding press) method and self-loaded molding method for 9,000 times and measured the lenses shape accuracy and surface roughness to evaluate the core life. As a result the self-loaded molding method core has 2,000 times longer that GMP (Glass molding press) method. If we adopt self-loaded molding method of the optical aspherical lens molding in the future, we expect that it would reduce the expense of changing the molds by molding core life improvements.

A Study on the Desired Target Signal Estimation using MUSIC and LCMV Beamforming Algorithm in Wireless Coherent Channel

  • Lee, Kwan Hyeong
    • International journal of advanced smart convergence
    • /
    • v.9 no.1
    • /
    • pp.177-184
    • /
    • 2020
  • In this paper, we studied to direction of arrival (DoA) estimation to use DoA and optimum weight algorithms in coherent interference channels. The DoA algorithm have been considerable attention in signal processing with coherent signals and a limited number of snapshots in a noise and an interference environment. This paper is a proposed method for the desired signal estimation using MUSIC algorithm and adaptive beamforming to compare classical subspace techniques. Also, the proposed method is combined the updated weight value with LCMV beamforming algorithm in adaptive antenna array system for direction of arrival estimation of desired signal. The proposed algorithm can be used with combination to MUSIC algorithm, linearly constrained minimum variance beamforming (LCMV) and the weight value method to accurately desired signal estimation. Through simulation, we compare the proposed method with classical direction of in order to desired signals estimation. We show that the propose method has achieved good resolution performance better that classical direction arrival estimation algorithm. The simulation results show the effectiveness of the proposed method.

An Optimal Design for Truss Core Unit of Railway Carbody of Aluminum Extrusion Plate (알루미늄 압출재를 사용한 철도차량차체의 단위 압출재 최적설계)

  • 장창두;하윤석;조영천;신광복
    • Journal of the Korean Society for Railway
    • /
    • v.6 no.3
    • /
    • pp.194-202
    • /
    • 2003
  • To make railway carbody light in weight has advantages at some aspects of both manufacturing and maintenance. Recently, railway carbodys of steel structure have been lightened their weight by using aluminum extrusion plate. for the additional lightening of railway carbody, an optimal design which maintains proper strength and minimizes weight must be achieved. Optimization which is used with finite element analysis for aluminum extrusion plate has the disadvantage of consuming much time. In this paper, the method of equivalent material property which is available to FEA code is established using the method of equivalent stiffness. This method for plate is expanded into the method for railway carbody structure with plates and shells. An objective function is established for maximum stiffness of unit aluminum extrusion plate using established method of equivalent material property. We performed an multi-objective optimization using the penalty function method. As a result, recommendable shapes and sizes of unit extrusion plate for under-frame of high speed train is presented.

A Study of the New Body Surface Area Calculation for Twenties Women (20대 여성을 위한 새로운 체표면적 산출식에 관한 연구)

  • Im, Soon
    • The Research Journal of the Costume Culture
    • /
    • v.7 no.2
    • /
    • pp.275-288
    • /
    • 1999
  • The purpose of this is providing a simple, relatively errorless body surface area calculation. Subjects were 10 married women and 10 singles women whose age was 20 to 29 years old. The Gypsum method has applied for the sampling of body surface. The Weight method has been used to measure body surface by means of transferring gypsum shape on uniform plane polypropylene films. In this study, compare analyzed errors between the traditional formulas for measuring body surface area and measuring data in this experiment. More than all, it has been to induce a regression equation for measuring body surface area, which is so simple to calculate with less errors, with variable factors as weight and height. The results of this experiment as follows : 1. In the traditional formulas, weight formula was shown high average error : Niya\`s height formula. which was modified K value as 0.62 in the height formula (S = KH) is shown lower average error than Lassabliere\`s Height formula. 2. In the weight-height formula (S=K √WH), it was shown high average error according to the increasing of K value. Kawanami\`s formula, which 5.378 as K value, was shown low average error both the singles and the married women. 3. Dubois weight-heingt formula (S=W/sup a/·H/sub b/·K) was shown low average error than the weight, height, weight-height (S=K√WH) formula. 4. The regression equations with variable factors as weight and height are 156.74W + 86.05H - 660.25 (Single women) and 136.02W + 90.57H - 6241.32 (Married women) the average error and absolute average error to the singles are 0.09%, 0.94% and resoectively -0.13%, 1.16% for the married women.

  • PDF

Calibration Method of Vehicle Weight Data from Weigh-In-Motion System According to Temperature Effects (온도의 영향에 대한 Weigh-In-Motion 시스템의 차량중량자료 보정기법)

  • Hwan, Eui-Seung;Lee, Sang-Woo
    • International Journal of Highway Engineering
    • /
    • v.12 no.4
    • /
    • pp.187-196
    • /
    • 2010
  • The purpose of this study is to develop the calibration method for temperature effects to improve the accuracy of the Weigh-In-Motion(WIM) system for collecting long-term truck weight data. WIM system was installed at a location where the truck traffic volume is high and weight data has been collected from January 2010. In this study, as a calibration measure, the first axle weight of Truck Type 10, the semi tractor-trailer is used based on the fact that the first axle weight is relatively constant, independent of the cargo weight. From this fact, calibration equations are developed from the relationship between the axle weight and the temperature(daily mean, maximum and minimum). Analysis on calibrated weight data shows adequacy of the proposed calibration method. Results of this study can be used to improve the accuracy of the WIM system and to carry out more rational design of pavement and bridge structures.

THE t-WISE INTERSECTION OF RELATIVE THREE-WEIGHT CODES

  • Li, Xin;Liu, Zihui
    • Bulletin of the Korean Mathematical Society
    • /
    • v.54 no.4
    • /
    • pp.1095-1110
    • /
    • 2017
  • The t-wise intersection is a useful property of a linear code due to its many applications. Recently, the second author determined the t-wise intersection of a relative two-weight code. By using this result and generalizing the finite projective geometry method, we will present the t-wise intersection of a relative three-weight code and its applications in this paper.

A STANDARD METHOD FOR JOINTING CAMEL CARCASSES WITH REFERENCE TO THE EFFECT OF SLAUGHTER AGE ON CARCASS CHARACTERISTICS IN NAJDI CAMELS. I. WHOLESALE CUT WEIGHT

  • Abouheif, M.A.;Basmaeil, S.M.;Bakkar, M.N.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.3 no.2
    • /
    • pp.97-102
    • /
    • 1990
  • A procedure to standardize camel carcass fabrication is proposed. This includes a definitive method of jointing the carcass into wholesale neck, shoulder, brisket, rib, plate, loin, flank, rump and leg cuts. Carcass cutout data were collected from the right sides of 21 Najdi male camels averaging 8, 16 and 26 months of age in order to determine the influence of age on the weight of each wholesale cut. The weight of body, empty body, hot carcass, cold carcass, hump fat, kidney, pelvic and heart fat (KPH) and each wholesale cut increased (p < .01) with age. Except for percent shrinkage and wholesale rump weight, all studied traits increased (p < .01) linearly as the age increased. This change was most pronounced in wholesale flank and plate cuts, increasing by 4.2 and 3.4 times, respectively, while the rump and shoulder cuts changed the least, increasing by 1.8 and 1.9 times, respectively. Allometric growth coefficients indicated that as the camel grew, the weight of rib, brisket, plate and flank cuts increased relatively more rapidly than did cold carcass or empty body weight and that the weight of wholesale shoulder, neck, leg and rump increased less rapidly than did cold carcass or empty body weight.