• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.101-109
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• 2004

Ship structures is thin-walled structures and she has lots of curved platings. In these days, lots different kinds of closed-formulas are development for ultimate strength of flat plate but for curved panels, there are not enough study or papers for this field. In this study, the ultimate strength characteristics for ship curved plates are studied. The ship plating is generally subjected to combined in-plane and lateral pressure loads. In-plane loads included biaxial compression/tension and edge shear. This is first report about the developing of ultimate compressive strength for ship curved plating. A closed-form formula for predicting the ultimate compressive strength of curved plates are empirically derived by curve fitting based on the computed results. The results and insights developed in the present study will be useful for damage tolerant design of curved plated structures.

• Kyungpook Mathematical Journal
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• 제55권2호
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• pp.473-484
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• 2015

Archimedes determined the center of gravity of a parabolic section as follows. For a parabolic section between a parabola and any chord AB on the parabola, let us denote by P the point on the parabola where the tangent is parallel to AB and by V the point where the line through P parallel to the axis of the parabola meets the chord AB. Then the center G of gravity of the section lies on PV called the axis of the parabolic section with $PG=\frac{3}{5}PV$. In this paper, we study strictly locally convex plane curves satisfying the above center of gravity properties. As a result, we prove that among strictly locally convex plane curves, those properties characterize parabolas.

• ETRI Journal
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• 제38권6호
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• pp.1095-1103
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• 2016

We present a method for transferring deformation weights of a human character to three-dimensional (3D) scanned clothes. First, clothing vertices are projected onto a character skin. Their deformation weights are determined from the barycentric coordinates of the projection points. For more complicated parts, such as shoulders and armpits, continuously moving planes are constructed and employed as projection reference planes. Clothing vertices on a plane are projected onto the intersection curve of the plane with a character skin to achieve a smooth weight transfer. The proposed method produces an initial deformation for physically based clothing simulations. We demonstrated the effectiveness of our method through several deformation results for 3D scanned clothes.

• 한국자동차공학회논문집
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• 제6권6호
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• pp.15-23
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• 1998

A three dimensional simulation of the fluid flow in an automotive torque converter was conducted adopting the mixing plane model implemented in the computational fluid dynamics program CFD-ACE. The present numerical results for performance characteristics showed a good agreement with the experimental results. In the flow of the torque converter, recirculating flow regimes were found mostly at the suction side of each element, which caused the performance decrease. The recirculating flow can be minimized by the optimization of the blade geometries.

• 한국정밀공학회지
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• 제11권2호
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• pp.104-109
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• 1994

This research describes some developments of computer-aided process planning and die design for hot forging products of H-shaped plane strain produced by the press. The system is composed of three main modules(process planning module, die design module and simulation module) which are used independently or in all. Systm capabilities include as follows: 1. In die design module, using the results of process planning module, the shape and size of bolcker and finish die in each operation are determined and the ouput id generated in graphic form for manufacturing drawing. 3. In simulation module, the flow pattern of workpiece and the load/stroke curve are approximately predicted. Design rules for process planning and die design are extracted from plasticity theories, handbooks, relevant references and empirical know-how of field experts in hot forging companies. The developed system provides poweful capabilities for process planning and die design of hot forging products.

• 천문학회보
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• 제46권2호
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• pp.43.4-43.4
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• 2021

One of the most promising secondary target programmes of DESI is the peculiar velocity survey, which will notably improve the measurements of cosmology parameters in the low-redshift universe. We use the Fundamental plane and Tully-Fisher relation as distance indicators to calculate peculiar velocities for DESI. This required additional observations to obtain spectra with sufficient quality to measure the velocity dispersions in the case of the fundamental plane, and to get off-centre redshift measurements to reconstruct the rotation curve in the case of the Tully-Fisher relation. However, we devised a clever strategy for suitable target galaxies, that takes advantage of the spare fibres of DESI to gather the required additional data without causing conflicts with the main survey programmes. We provide a brief overview of the preliminary results and success rate based on the first measurements obtained during survey validation as well as an outlook on expected improvements in the fσ₈ measurements once the survey has been completed.

• 한국구조물진단유지관리공학회 논문집
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• 제25권1호
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• pp.16-24
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• 2021

이 연구에서는 강봉 트러스 시스템으로 보강된 조적벽체의 면내·외 거동에 대한 내진성능을 평가하였다. 강봉 트러스 시스템 보강은 무보강 조적벽체 1면에 2개의 강봉 트러스 시스템 유닛을 배치하였다. 면내 거동에 대한 실험결과는 무보강 조적벽체 및 벽체 1면에 1개의 강봉 트러스 시스템 보강된 조적벽체와 비교하였으며, 면외 거동에 대한 실험결과는 무보강 조적벽체와 비교하였다. 실험 결과, 강봉 트러스 시스템으로 보강된 조적벽체의 면내·외 초기 강성은 무보강 조적벽체에 비해 각각 1.9배 및 2.3배 높았으며, 면내·외 최대 내력은 각각 1.8배 및 1.9배 높았다. 특히 강봉 트러스 시스템으로 보강된 조적벽체의 면내·외 에너지 소산능력은 무보강 조적벽체에 비해 각각 6.1배 및 2.4배 높았으며, 등가 감쇠비는 각각 5.1배 및 1.2배 높았다. 즉, 강봉 트러스 시스템은 무보강 조적벽체의 면내 방향으로의 내진성능 향상뿐만 아니라 면외 방향으로의 내진성능 향상에도 유리할 것으로 판단된다.

• 한국지반공학회논문집
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• 제36권11호
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• pp.51-60
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• 2020

횡방향의 토압에 저항하는 앵커블록, 흙막이 가설벽체, 레이커 지지블록 등에서 수동토압 산정은 중요한 요소이다. 실무에서는 사용의 편의성으로 인하여 파괴면을 직선으로 가정한 Coulomb과 Rankine의 이론을 사용하여 토압을 산정하는 것이 일반적이다. 하지만 실제 발생하는 수동파괴면은 벽면과 지반의 마찰로 인하여 벽체부근에서는 곡면이고 지표부근에서는 평면이 되는 복합파괴면을 형성한다. 흙막이 구조물의 안정검토에서 저항력으로 산정되는 수동토압이 발생되는 변위는 주동토압이 발생되는 주동변위 보다 커 대부분 구조물의 안정성을 초과하는 변위가 발생하여야 수동토압의 저항력이 발휘되므로 수동토압을 설계에 적용하기 위해서는 허용변위 이내의 임의변위에서 발휘되는 수동측토압의 산정이 매우 중요한 요소이다. 본 연구에서는 복합파괴면을 반영한 한계변위 내의 임의 변위에서 발휘되는 수동측토압을 산정할 수 있는 반경험식을 활용하여 벽체의 세 가지 거동조건에 따라 임의 변위에서 발휘되는 수동토압을 분석하였다.

• 한국화재조사학회지
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• 제3권1호
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• pp.12-15
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• 2003

The purpose of this study is to distinguish the causes of broken glass from doors or windows when it is found being originally kept among the remains on the floor in fire site - whether it was broken due to heating or by outer power through test and the properties of the broken plane including the pattern on the plane. Addition to it, the study tries to find characteristics for judging the point and direction of breakdown through the analysis of glass broken by outer power. With two causes assumed - a. breakdown due to heating and b. breakdown due to outer power - 3 pieces of glass plates $(30cm{\times}30cm{\times}5mm)$ for each case were tested, getting the results as following: 1. For the glass broken due to the change of temperature The broken plane is of slow curve and smooth without any pattern. 2. For the broken due to outer power With the impact point as the center, the shows breakdown of radial type and the side shows breakdown of near-perpendicular type. The far the broken piece is from the impact point, the bigger the size is. The broken piece at the impact point is of long triangle type and the two long planes of the triangle shows semi-arc with the center of breakdown point and the other plane shows opposite pattern 3. Change of the pattern and type of the glass due to outer power The pattern and type of the glass due to outer power shows change due to heatihg.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.431-436
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• 2006

The latest system of GIS has been changing from 2 dimension to 3 dimension. According to the rapid growth of the fields linked to 3D GIS, 3D GIS has variously affected the public field, the national defense field, and the industrial field. This study estimated sight distance safety of curve section considering the environmental impact based on 3D GIS. Sight distance is calculated from the relation between road which keeps the three-dimension character and driver gaze, so it needs to consider both plane and vertical ior the accurate measuring. This study made analysis of the sight distance through considering the environmental impact with driving simulation of design speed 80km/h and running speed 60-120km/h.