• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.453-454
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• 2010

포장콘크리트 시공특성을 고려한 합리적 품질검사 기준을 수립하기 위하여 KS Q 0001을 준용한 포장콘크리트 로트 크기에 대한 통계적 분석을 실시하였다. 그 결과, 설계기준휨강도를 보증하기 위한 합리적인 품질검사기준으로는 1일 $300m^3$마다 1회 시험이 적정한 것을 알 수 있다.

• Structural Engineering and Mechanics
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• 제59권6호
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• pp.1095-1120
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• 2016

This paper investigates the change of structural characteristics of steel cable-stayed bridges after cable failure. Cables, considered as the intermediate supports of cable-stayed bridges, can break or fail for several reasons, such as fire, direct vehicle clash accident, extreme weather conditions, and fatigue of cable or anchorage. Also, the replacement of cables can cause temporary disconnection. Because of the structural characteristics with various geometric nonlinearities of cable-stayed bridges, cable failure may cause significant change to the structural state and ultimate behavior. Until now, the characteristics of structural behavior after cable failure have rarely been studied. In this study, rational cable failure analysis is suggested to trace the new equilibrium with structural configuration after the cable failure. Also, the sequence of ultimate analysis for the structure that suffers cable failure is suggested, to study the change of ultimate behavior and load carrying capacity under specific live load conditions. Using these analysis methods, the statical behavior after individual cable failure is studied based on the change of structural configuration, and distribution of internal forces. Also, the change of the ultimate behavior and load carrying capacity under specific live load conditions is investigated, using the proposed analysis method. According to the study, significant change of the statical behavior and ultimate capacity occurs although just one cable fails.

• 대한조선학회지
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• 제18권1호
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• pp.39-43
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• 1981

The auther presents two simplified methods of stability analysis for small vessels. The paper includes a brief review of some excellent papers recently published. The righting arm and moment of inertia of trimmed waterplane resulted from two methods are compared with. The conclusion is reached that CTTM is more adequate than CTM to ensure statical stability for vessels.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.499-504
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• 2012

The high-speed train enjoys widespread acceptance as environment-friendly means of medium- to long-distance transportation. The pursuit of higher speed and lighter weight in railroad vehicles has engendered higher noise level. In particular, the environmental noise places many restrictions in the operation of high-speed railroad vehicles. This research investigates the effect of installing a skirt onto a high-speed train bogie with the top speed of 400 km/hr and using High Speed EMU for the purpose of reducing the environmental noise. In order to analyze the effect of the interior noise and environmental noise due to installation of the skirt, sound level is calculated using the Ray method and Statical Energy Analysis method. The numerical calculation predicts a reduction of approximately 2 dB in the environmental noise level, but at the cost of increase of approximately 2.5 dB in the interior noise level of the vehicle.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.261-265
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• 2002

In the machining tool avoid vibration problem have an effect on high precision as well as statical and thermal characteristics. Therefore overcome this problem is essential to advance of machine tool and machining skill. Even though vibration arises owing to a variety of causes, in this paper vibration analysis of column as a major part of machine tool structures is presented. At this procedure vibration analysis applied to mode synthesis method using a attachment mode .

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1797-1802
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• 2005

In this study, we were developed an accuracy of the proposed two dimensional statical inclinometer what used a position sensitive detector(PSD) by an error analysis. The inclinometer consists of a laser source, a mass, an optic-fiber, and a PSD. The gravity direction on a base platform of the inclinometer is changed by an unknown inclination angle. And a laser spot is moved from the origin to another position of a PSD following a variation of an optical path by the gravity. These processes enable the inclinometer to estimate the inclination angle from distance information of the moving spot. A design methodology on the basis of a sensitivity analysis was applied to improve the measurement performance such as a full measuring range and a resolution. But it still has error factors, so we analyze the uncertainty of the inclinometer to evaluate the systematic errors from alignments, assembly error and so on. The experimental performance evaluation about the design objectives as a measuring range and a resolution was performed. And the validity and the feasibility of the design process were certified by an experimental process. Systematic errors eliminated to improve the accuracy of the inclinometer by the corrected measuring model from the calibration process between the inclination angle and the PSD position instead of the nominal measuring model. The ANOVA(analysis of variance) confirmed the effect of eliminating the systematic errors in the inclinometer. From these methodologies, the proposed inclinometer was able to measure with a high resolution(35.14sec) and a wide range(from $-15^{\circ}\;to\;15^{\circ}$

• 대한토목학회논문집
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• 제2권3호
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• pp.57-66
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• 1982

본(本) 연구(硏究)는 불규칙적(不規則的)인 지지형태(支持形態)를 갖는 곡선항교(曲線桁橋)의 정적(靜的) 해석(解析)에 관(關)한 것으로서 그 목적(目的)은 소형(小型) 전자계산기(電子計算機)에 의해 곡선항교(曲線桁橋)의 단면력(斷面力)과 변위량(變位量)을 구하기 위한 해법(解法)을 제시(提示)하는 데 있다. 본(本) 연구(硏究)서는 곡선항교(曲線桁橋) 단면특성(斷面特性)과 풀이식(式)의 실제설계(實際設計)에의 이용(利用) 가능성(可能性)을 고려(考慮)하여 전달(傳達)매트릭스법(法)을 적용(適用)하였다. 이 전달(傳達)매트릭스법(法)은 소형(小型) 전자계산기(電子計算機)에 의한 구조해석(構造解析)에 효율적이며 보편적으로 사용되는 전산해법(電算解法)이다. 또한 본(本) 연구(硏究)에서는 부재중심각(部材中心角)으로 나누어지는 항(項)을 제거시킴으로써 항(桁)의 곡선(軸線)이 직선화(直線化)되어도 풀이가 가능(可能)하도록 하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 가을 학술발표회논문집
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• pp.355-360
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• 2000

This paper presents properties of piecewise cubic B-spline function and Rayleigh-Ritz method to compute the smallest eigenvales. In order to compute the smallest eigenvalues, Rayleigh quotient approach is used and four different types of finite element approximating functions corresponding to the statical deflection curve, spanned by the linearly independent set of piecewise cubic B-spline functions with equally spaced 5 knots from a partion of [0, 1], each satisfying homogeneous boundary conditions with constraining effects are used to compute the smallest eigenvalues for a Sturm-Lionville boundary equations of u"＋ λ²u＝0, u(0.0)＝u(0.0)＝0, 0≤x≤1.0.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1102-1107
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• 2004

High-speed railway bridges subject to effect of statical loads by temperature change as well as dynamic loads by interaction between vehicle load which run specially fast and behavior of bridges, If suitable longitudinal expansion by temperature change of bridge does not happened, it can cause unhealthy condition for the parts of bridges as well as can generate addition stress to bridges, For these reason, Analysis and Estimation of data about behavior of bridges occupies important factor in that estimate the remaining life of bridges and select the maintenance, repair and retrofit. In this paper, Analysis for the long-term behavior of bridges using Longitudinal displacement and Temperature data that is actuality measured data to the bridges of Seoul-Busan high speed railroad test section has been made.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 2003년도 공동 춘계학술대회 논문집
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• pp.523-528
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• 2003

본 연구는 지가의 공간분포 분석(spatial data analysis)을 통하여 합리적인 표준지 선정 방안을 제시하고자 하였다. 우리나라의 경우 개별 공시지가는 표준지 공시지가로부터 비교해서 산정된다. 때문에, 표준지는 개별지의 지가를 산정하는데 편리할 수 있도록 선정되어야 한다. 이를 위하여 표준지를 선정할 때, 개별지의 지가와 토지특성을 고려하여 표준지의 수와 공간적 분포를 결정하여야 한다. 본 연구에서는 지가의 공간적 분포를 해석하기 위하여 군집분석(cluster analysis) 개념을 활용하였다. 이를 통하여 유사 지가구획을 정의하였고, 지가구획의 계층적 해석을 시도하였다. 또한, 군집분석을 반복적으로 수행하고 군집수의 변화에 따른 군집별 지가분포의 특성을 해석함으로써 적정표준지 수를 추정하였다.