개선된 탄성지반상 보의 휨해석

鄭熺孝,安光列,李承烈,朴泳珏 경상대학교 생산기술연구소 2002 工學硏究院論文集 Vol.2 No.-

The BEF(Beam on Elastic Foundation) analogy was first noted by Vlasov and then utilized for the distortional analysis of box girders by Wright et al., but it was limited only to prismatic straight box girders. With the development of this study, a more generalized element in a stiffness matrix form was presented. With this element, which is "equivalent" to the BEF(Beam on Elastic Foundation) analogy, more complicated configurations can be resulted. In this study, it compares analysis results using the traditional trigonometric function to solve a BEF(Beam on Elastic Foundation) problem with analysis results using stiffness matrix form to solve a EBEF(Equivalent Beam on Elastic Foundation).

OPTIMAL CONTROL PROBLEM IN A TUMOR MODEL WITH IMMUNE SUPPRESSION EFFECTS

Kwang?Su KIM,Il-Hyo JUNG 한국산업응용수학회 2013 한국산업응용수학회 학술대회 논문집 Vol.8 No.1

중간스프링을 가진 개선된 탄성지반상(彈性地盤上) 보의 휨해석

鄭熺孝,李承烈,安光列 慶尙大學校 經營行政大學院 2004 工學硏究院論文集 Vol.20 No.-

While the BEF(Beam on Elastic Foundation, Wright et al, 1968) analogy has been widely used in straight and simple supported box girder analysis, the EBEF(Equivalent Beam on Elastic Foundation, Yao. T. Hsu et al, 1995) analogy has been made possible in curved and continuous box girder. Instead of using the traditional trigonometric foundation to solve a BEF problem, EBEF analogy used stiffness matrix considering bending, shear, elastic foundation and defined middle diaphragms in box girder as middle supports of continuous beam. In this study, for the comparison with BEF analogy, the element length of beam is determined first and infinity support stiffness corresponding to dimensionless middle diaphragm stiffness is determined in EBEF analogy. Two approaches, BEF and EBEF analogy are compared in the beam on elastic foundation.

거더의 單純化 解析에 관한 硏究

鄭熺孝,安光列 慶尙大學校生産技術硏究所 1999 生産技術硏究所論文集 Vol.15 No.-

A simplified method to analyze pin-ended girders under uniform load is presented. This method is shown to estimate the maximum moment, shear and deflection of the girder without calculating any of the beam reactions it supports. If exact solutions for the maximum moment, shear and deflection are needed, they can be easily found by multiplying the approximate results by a tabulated constant. Results are valid for any type of pin-ended girder, provided structures are made by uniformly spaced beams or trusses. This method can easily be programmed into a spreadsheet, calculated by hand or incorporated into an existing software package.

隔壁의 傾斜에 따른 箱子桁의 硏究

鄭熺孝,安光列,李承烈,朴泳珏 경상대학교 생산기술연구소 2002 工學硏究院論文集 Vol.2 No.-

The box girder has became a popular bridge type for long span or curved bridges because of its structural advantage of torsional stiffness. Generally box girder have inner diaphragms. The purpose of diaphragms is to prevent the deformation of cross section shape. Most diaphragms are parallel to cross section but it is necessary at present to adapt the design of bridge structures to transport requirement and the restrictive conditions of environment. City bridges, bridges spanning railway lines and stations, skew crossing of streets and highways, etc., require an irregular arrangement of internal supports. If diaphragms are applied, they are usually skew. It is advantageous to use a box girder as the basic component for a bridge of this kind because the box girder provides a high torsional stiffness, a favorable stresses, and due to the small shear stresses arising due to torsion. This paper deal with the analysis of the function of irregularly situated support and skew diaphragms and with their influence on the resulting state of stress of the box girder and compare with vertical deflections, horizontal deflections, longitudinal stresses, distortional stresses according to the angle of diaphragms.

편심하중을 받는 상자형의 단면변형에 관한 연구

鄭熺孝,安光列,金鎬洙,黃俊碩 경상대학교 생산기술연구소 2001 工學硏究院論文集 Vol.1 No.-

Eccentric load acts on box girder is divided into bending and torsional load and deforms cross section. Distortion that is resulted from torsional load is largely different according to tickness of each plate or stiffener. According to with and without regard of distorsion effect, it is possible to divide analysis of box gilder into two. First, analysis of box gilder can be able to calcurate with rigid box girder in assumption that there is no distorsion when the girder is well stiffened with diaphragms or cross bracing and plate thickness of box section is thick. Second is the analysis that must be considered effect of distorsion when the girder has not sufficient stiffener or plate thickness of box section is not well thick. In numerical example of this study, normal stress of rigid cross section analysis is compared with that of deformable cross section analysis without interior diaphragms. Then, it was studied that stresses of the deformable cross section analysis can be near rigid analysis when box girder was stiffened with interior diaphragms.

경사격벽을 가진 상자형의 해석

鄭熺孝,安光列,李承烈,朴泳珏 경상대학교 생산기술연구소 2001 工學硏究院論文集 Vol.1 No.-

It is necessary at present to adapt the design of bridge structures to transport requirement and the restrictive conditions of environment. City bridges, bridges spanning railway lines and stations, skew crossing of streets and highways, etc., require an irregular arrangement of internal supports. If diaphragms are applied, they are usually skew. It is advantageous to use a box girder as the basic component for a bridge of this kind because the box girder provides a high torsional stiffness, a favorable stresses, and due to the small shear stresses arising due to torsion. This paper deal with the analysis of the function of irregularly situated support and skew diaphragms and with their influence on the resulting state of stress of the box girder. The solution is shown for a box girder under eccentric load and according to the length of skew diaphragms.

3차식 상태방정식을 이용한 고압기액평형의 계산 : Maximum Likelihood 의 원리에 의한 Parameter 의 결정과 일반화 Determination and Generalization of Parameters by Principle of Maximum Likelihood

배효광,정해익 嶺南大學校 工業技術硏究所 1990 연구보고 Vol.18 No.1

The vapor-liquid equilibria at high pressure are predicted by using Peng-Robinson's equation of state. The interaction and size parameters included in the equation of state are obtained by optimization based on the principle of maximum likelihood. The optimal size parameter ηij is nearly equal to unity for 100 binary systems composed of carbon dioxide-hydrocarbon, methane-hydrocarbon and hydrocarbon-hydrocarbon, which are extremely unsymmetric systems. This fact means that it is not necessary to introduce the size parameter(ηij) into the equation of state. The interaction parameter ηij depends irregularly on temperature for all the binary systems and it is more sensible to the error of experimental variables than the temperature of system. More accurate observed date are, therefore, needed to investigate the temperature dependence on the interaction parameter.

초임계프로판에 의한 폐윤활유의 재생과 공정의 경제성

전정호,박민우,배효광 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.2

The feasibility of supercritical extraction processes of waste lubricating oil by estimating the production costs of re-refining oil was discussed. The process was carried out at the supercritical condition of 150 and 100 bar, which was the optimum regeneration condition for waste lube oil and had already established using half and full-contineous appratus of supercritical exctraction. The supercritical extraction of waste lube oil was estimated to cost down 10%∼20% of brand-new oil.

飮食物쓰레기의 效率的 管理를 위한 物理的 特性 및 處理

권효정,정영헌,김임경,심언봉,오광중 부산대학교 환경문제연구소 2003 環境硏究報 Vol.21 No.-

This study was conducted to manage food wastes in Korea efficiently. We carried out an experiments on food wastes generated from Yeonjae gu, Pusan as a representative boundary according to the measurement of apparent density, generation quantity, physical characteristics, proximate analysis, and elemental analysis as well as drying and carbonizing, and also tested the hazardous materials in fertilizer and compost from public and private recycling center in operation. The purposes of this study are to investigate current status of food wastes recycling methods and facilities, to examine the fuelization of food wastes, and to suggest the cost effective food wastes treatment plans. Based on the results of the analysis of apparent density and water content in food wastes, it was revealed that the apparent density of food wastes was in inverse proportion to the water content. The water content of food wastes was highly influenced by the fruit and vegetables such as watermelons. These results indicate that the food wastes with about 75 ~80wt% initial moisture content should be reduced under 70wt% moisture content by drying process pier to throwing away. Comparing the heating values of the food wastes which were calculated by Dulong's equation and Steuer's equation it was revealed that Steuer's equation(HHV 5,186 kcal/kg, LHV 880 kcal/kg) was more compatible than Dulong's equation(HHV 4,676 kcal/kg, LHV 330 kcal/kg) because the results of proximate analysis for the food wastes were very similar to those of sewage sludges. Additionally, to reduce water contents of food wastes under 60wt% as acceptable water contents for fuelization, it was also found that blending with 25wt% chars made from food wastes was more efficient than the drying of food wastes itself at 105°C, 45minutes in view of completion time. Furthermore, these chars generated from food wastes (about LHV 6,608 kcal/kg) comparable to commercial charcoal(LHV 7,134 kcal/kg) generated from oak trees and lower ash contents(under 15wt% of chars) than those.