• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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• pp.193-200
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• 2004

In this study, the impact load on bridge by vessel collision in consideration of fender system is evaluated by numerical method. The bow of object vessel(DWT5000) is standardized, and modeled by shell elements. The main body of objective vessel is modeled by beam elements that present mass distribution and stiffness of vessel. The buoyancy effect of vessel is considered as linear spring. The two types of fender systems, such as steel and rubber are analyzed in this study. In steel fender system, the steel plates that absorb collision energy by its collapse are modeled by shell element with stiffener. The steel is material modeled elastic-plastic material. In the rubber fender system, the rubber material is modeled hyper-elastic material and the main body of fender is modeled by solid elements. The global impact responses of vessel and fender system are evaluated by explicit dynamic scheme. The results show that the magnitude of vessel collision force are depended on the material behavior of fender system. Also the values of collision load are conservative compare to the those of design codes.

• 한국신뢰성학회지:신뢰성응용연구
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• 제8권2호
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• pp.87-100
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• 2008

The rubber fender is used to absorb the berthing energy that is produced when a ship is near a port, and it prevents collision between the ship and port. If the rubber fender becomes defective, the berthing energy cannot be absorbed when it is near the port, and damage can result from collisions due to the hardening process. In this research, when the rubber fender is heated, collisions can cause cracks and other damage. It is also confirmed from the research the lifetime distribution of the rubber fender. The researcher has predicted using different variables and elongation that a rubber fender has an 11year lifespan at $20^{\circ}C$.

• 대한조선학회논문집
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• 제42권1호
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• pp.43-49
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• 2005

in this paper a dolphin-fender moored pontoon-type floating structure in shallow water depth is studied focusing on mooring force. The pontoon-type floating structure is 500m long, 300m wide. The structure has partially non-uniform drafts of 2.0m and 3.0m. The employed mooring system is a guyed frame type dolphin-fender system. The 1/125 scale model fender system is made of rubber tube to have hi-linear load deflection characteristics. A series of model tests has been conducted focusing on motion and fender force responses in regular and irregular waves at KRISO's ocean engineering basin Non-linear numerical simulation of fender reaction force has been carried out and the results are compared with those of model tests. The simulated rigid body motion and mooring forces also have been compared with the test results.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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• pp.696-703
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• 2005

Recently, the collision problems between a bridge and a navigating ship are frequently issued at the stage of structure design. Even the many study results about vessel to vessel collision are presented, but the collision studies between vessel and bridge structure have been hardly presented. In this study, nonlinear dynamic analysis of vessel and fender system carry out using ABAQUS/Explicit commercial program with consideration of some parameters, such as bow structure we composed to shell element also ship's hull is modeling to beam element. Also, buoyancy effect is considered as spring element. The two types of fender systems was comparable with both collision analysis about steel materials fender system and rubber fender system On the purpose of study is analyzed the plasticity dissipated energy of vessel and fender system. We blow characteristic that kinetic energy is disappeared by plastic large deformation in case of collision. Also, We considered dissipated kinetic energy considering friction effect.

• Elastomers and Composites
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• 제54권1호
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• pp.70-76
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• 2019

The function and purpose of the marine rubber fender, to prevent the damage of the ship and the mooring while the ship is being attached to the pier. However, maintenance of the fender after installation is not enough, because it is generally handled as an attachment facility. Estimation the life of a marine rubber fender is important in the maintenance of a port. When manufacturers design and produce marine rubber fenders, they do so according to various conditions such as the reaction force acting on the hull and docking vessel and deformation after absorbing the kinetic energy of the ship. In this study, a method for predicting and evaluating service life from the product design and development stage was established, in order to evaluate the durability of the marine rubber fenders. The SSp-300H and HSP-300H models were used to predict the service life. The method developed in this study, is expected to predict the service life of the marine rubber fender accurately and in a comparatively shorter time, thereby contributing to the evaluation standard and quality stability of the product.

• 한국전산유체공학회지
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• 제20권1호
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• pp.1-9
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• 2015

A developed code is applied to simulate relative motion of floating bodies in a side-by-side arrangement, including effects of a fender and a hawser. The developed code is based on the flux-difference splitting scheme for immiscible incompressible fluids and the hybrid Cartesian/immersed boundary method. To validate the developed code for free surface flows around deforming boundaries, the water wave generation is simulated, which is caused by bed movement. The computed wave profile and time histories of wave elevation are compared with other experimental and computational results. The effects of a fender and a hawser are modeled by asymmetric force acting on the floating bodies according to a relative displacement with the bounds, in which the fender and the hawser exert no force on the bodies. It has been observed that the floating body can be accelerated by a gap flow due to a phase difference caused by the free surface. Grid independency is established for the computed time history of the body velocity, based on three different size grids.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2013년도 춘계학술대회
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• pp.261-263
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• 2013

방충재(Fender)는 함정의 안전한 접안, 계류 및 선체를 보호하기 위하여 설치된 중요한 안벽시설 중 하나이다. 기존의 고무 방충재는 초기변형 28~30% 정도에서 가장 높은 반력이 발생하여 함정에 지속적인 힘을 가해주기 때문에 선체에 찌그러짐(dent)이 발생하게 되고, 검정색이 착색되기도 하여 선체에 심대한 훼손이 발생하게 된다. 이런 문제점을 개선하기 위하여 이 연구에서는 초기 반력이 적어 선체의 손상을 일으키지 않고 착색이 되어 선체가 더러워지는 현상을 막는 폼필드 펜더(Foam Filled Fender)를 직접 제작하여 그 결과를 제시하기로 한다.

• 한국소음진동공학회논문집
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• 제26권5호
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• pp.584-593
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• 2016

In this study, an improvement design method for reducing the vibration of fenders equipped in a tractor is proposed through the establishment of a finite element model and the topology optimization. As the original shapes of the parts cannot be altered, an improved design model was derived in which a stiffener was attached to the border of parts. Thus, the first resonance frequency was increased by approximately 16 Hz, which was confirmed to be the frequency interval for avoiding the idle and operating frequency of the engine. Finally the improved design model was applied to confirm the effect of vibration reduction. Therefore, it can be concluded that the improved design model of the tractor fender is effective at reducing vibrations of the tractor fender.

• 한국산학기술학회논문지
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• 제21권5호
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• pp.426-432
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• 2020

20세기 이후 미디어의 발달과 함께한 음악은 이전 시대에서는 상상하기 힘들었던 대중들의 삶과 음악이 서로 함께하는 시대로 변화를 맞이하게 된다. 이러한 문화적 흐름을 바탕으로 기존 문화에서 철저히 소외되었던 10대들의 음악이 주류로 진입한 사건인 록큰롤의 탄생과 그 배경에는 기타, 그 중에서도 솔리드 바디 일렉트릭 기타의 출현과 그 맥을 같이 한다고 볼 수 있다. 이렇게 일렉트릭 기타의 대명사로 일컬어지는 펜더 스트라토케스터는 록큰롤을 위시한 대중음악의 역사와 함께했다 해도 과언이 아닐 것이다. 현재까지도 많은 추종자와 세대를 아우르는 폭넓은 지지를 받는 막강한 영향력은 대중음악의 역사적 흐름과 일렉트릭 기타의 위상에 있어서도 현재까지 끊임없이 재생산되는 가교 역할을 했다. 또한 대중음악과 미디어의 비약적인 발전 속에서도 언제나 현재진행형으로 도구를 넘어 시대와 함께 하는 생명력에 진정한 의미와 가치를 들 수 있을 것이다. 본 논문에서는 이러한 펜더 스트라토케스터의 특징과 흔적들이 어떻게 나타나는지 살펴보도록 한다.

• 한국구조물진단유지관리공학회 논문집
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• 제26권2호
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• pp.28-36
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• 2022

매립지 위에 건설되는 항만시설물은 바람(태풍), 파랑, 선박과의 충돌 등 극한 외부 하중에 노출되기 때문에 구조물의 안전성 및 사용성을 주기적으로 평가하는 것이 중요하다. 본 논문에서는 항만 계류시설에 설치된 방충설비의 유지관리를 위하여 비전 및 딥러닝 기반의 방충설비 세분화(segmentation) 시스템을 개발하였다. 방충설비 세분화를 위하여 인코더-디코더 형식과 인간 시각체계의 편심 기능에서 영감을 얻은 수용 영역 블록(Receptive field block) 기반의 합성곱 모듈을 DenseNet 형식으로 개선하는 딥러닝 네트워크를 제안하였다. 네트워크 훈련을 위해 BP형, V형, 원통형, 타이어형 등 다양한 형태의 방충설비 영상을 수집하였으며, 탄성 변형, 좌우 반전, 색상 변환 및 기하학적 변환을 통해 영상을 증강시킨 다음 제안한 딥러닝 네트워크를 학습하였다. 기존의 세분화 모델인 VGG16-Unet과 비교하여 제안한 모델의 세분화 성능을 검증하였으며, 그 결과 본 시스템이 IoU 84%, 조화평균 90% 이상으로 정밀하게 실시간으로 세분화할 수 있음을 확인하였다. 제안한 방충설비 세분화 시스템의 현장적용 가능성을 검증하기 위하여 국내 항만 시설물에서 촬영된 영상을 기반으로 학습을 수행하였으며, 그 결과 기존 세분화 모델과 비교하였을 때 우수한 성능을 보이며 정밀하게 방충설비를 감지하는 것을 확인하였다.