• Journal of Advanced Marine Engineering and Technology
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• 제28권4호
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• pp.577-586
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• 2004

Structural failures, such as crack initiation, often arise near the bolted parts of the side member and trunnion bracket in some commercial vehicles. The purpose of this paper is: 1) establishment of a simple and practical bolted joint modelling technique and 2) determination of the key design variables for design improvement based on numerical experiments. Once the bolted joint modelling technique is established through experimental verification, the key design variables must be identified in order to alleviate the level of the stress concentration near the problem region. Numerical results indicate that the torsional rigidity of the frame cross-section should be increased to reduce the level of the maximum stress at the actual crack initiation location.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.801-806
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• 2000

This study deals with the design of snow plow for the special equipment vehicle. The purpose of the study is to develop the snow plow that can install in the special equipment vehicle such as clean up vehicle or dump truck in winter season. To do so, it is designed by 3 sub-assembly - snow shovel, main frame, and hydraulic cylinder and its support. The snow shovel consists of 3 pieces to meet the road profile and to exchange easily the damaged parts. Main frame connects the snow shovel with the hydraulic cylinder and its support and supports the weight of snow. Finally, the hydraulic cylinder and its support move the snow shovel up and down and tilt it. We designed it using 3D commercial CAD software for concurrent engineering design.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.120-124
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• 2003

NVH issue at idle condition is one of the major concerns of Passenger and Commercial Vehicle including Sports Utility Vehicle Especially steering wheel vibration at idle condition is a very complex problem and affected by firing frequency of the engine, stiffness of a steering wheel system and the body to which the steering wheel system is attached. To avoid vibration mode coupling between each system of a vehicle, experimental and analytical method has been used at the pre-prototype stage. The resonance frequency of the body and the frame has been decoupled by CAE and the resonance frequency of steering wheel system has been set in between the 1st bending frequency of body and frame. These Results has been used as design guidelines tot the prototype drawing stage. The experimental verification of tile modified pre-prototype vehicle shows good results of the vibration mode decouple. Modal test of prototype vehicle also confirms the vibration mode decouple between each system.

• 한국기계가공학회지
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• 제17권2호
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• pp.130-136
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• 2018

This study develops a seat with electric motor technology for a one-ton grade commercial vehicle. While applying electric motor technology, the FMVSS 210 seat frame strength test is also conducted to examine the product's weak parts. The seat frame strength test used the FMVSS 210 test standard and the ANSYS program was used to simulate the test and identify weak parts in the deformation and strain values. The test results showed that the cushion frame and slide rail connection bracket were fractured at loads of about 10,000 N. Similarly, the maximum stress and strain values in the bracket were obtained in the simulation results. On this basis, it was evaluated that the connection part bracket was a considerably weak part in the case of the first model, and changing the shape of the bracket and reinforcing the strength were required. In addition, the seat belt anchorage test results and simulation results were compared to assure their validity. In the comparison results, the error for each is about 5-10%. Therefore, the simulation performed in this study is considered to have produced reasonably accurate results.

• 한국자동차공학회논문집
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• 제25권3호
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• pp.360-366
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• 2017

In commercial vehicles such as frame-based mid-size trucks, it is easy to reduce vibration caused by driveline with the cab mount system. There are no critical driveline vibration problems associated with these vehicles up to now. However, in the case of a similar grade of monocoque type mini-bus, there are no effective vibration isolation components such as a cab mount. Vibration caused by driveline is quite a complex problem to understand in terms of which part governs the phenomenon and how the problem can be solved. Thus, we have to manage the design factor about the driveline and mount system strictly at the early stage of vehicle development. Low frequency vibration caused by the driveline system is investigated in this study. We created the CAE driveline model and analyze low frequency vibration. Then contribution analysis about each design factor of driveline and mount system is performed. Finally, we can obtain the optimized design factor for a driveline system of a mini-bus, which is verified by the vehicle test results.

• 한국기계기술학회지
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• 제13권4호
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• pp.131-136
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• 2011

In commercial vehicle, sub-frame which equipped in main frame supporting dump deck and oil tanker. This is the main structure for all equipment which including joint function. Sub-frame is made by welding process, this susceptible to deform and crack by its longitudinal size. Also various kind of sub-frame make it difficult to standardization in manufacturing process and exclusive jig is not adapted yet. Frame size is over 6~8m and weight is more than 300kg this make re-work more difficult. If manufacturing company made precise sub-frame, this is not only convenient for customers but also save the company money by reducing the working time. In this study manufacture the sub-frame be suitable for its main function and develop exclusive welding jig for obtain checking fixture function as well.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.32-36
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• 2010

This paper dealt with the flow simulation for the optimum designed propeller for Micro Aerial Vehicle, using a commercial CFD program(FLUENT). The propeller was modeled by the Multiple Reference Frame(MRF) method. For the validation of the computational method, the flow field analysis results for the propeller were compared with the flow analysis results, which are using Xfoil, for the optimum design, and with the wind tunnel data of a similar propeller model. By these validation processes, the reliability of MRF method was confirmed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.590-596
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• 2010

Maglev vehicles levitated and propelled by electromagnet as non-contact between vehicle and guide rail is environmentally friendly transport system which have many advantages like ride comfort and guide way construction costs. As a goal of commercial operation at Incheon International Airport in 2012, development of vehicle is underway and proto-vehicle is test running at KIMM. The maglev bogie system of proto-vehicle, like railway vehicle, has functions to support weight of vehicle, transfer force of brake and propulsion and improve ride comfort through insulation of vibration and improve curve negotiation capability. The main components of a bogie are two modules consisted of electromagnetic, frame and linear motor, two tie beams to connect two modules and steering system to improve curve negotiation capability. The purpose of this paper is to describe general specification, structure, manufacturing process, performance testing, ride comfort of proto-vehicle and bogie system.

• 한국군사과학기술학회지
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• 제13권5호
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• pp.933-940
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• 2010

A numerical analysis for the space frame structure under ballistic and blast loads was performed using LS-DYNA, a commercial code. The space frame structure was developed to be adapted to the ground vehicle in the future and it was designed to build with Al7039 frames and lightweight multi-layered panels for the purpose of weight reduction and shock mitigation. The analyses have done for side impacts by a cylindrical projectile and Comp. C-4 explosive representing major threats to the vehicle. The deformed shape of the panel section and stresses as well as accelerations of the frames calculated from LS-DYNA were compared to the test results to validate the analysis model. The internal energies for panels and frames from LS-DYNA were also compared to each other to discern their role in absorbing the ballistic and blast impact.

• 한국전산유체공학회지
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• 제20권2호
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• pp.81-87
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• 2015

For Underwater vehicles, Unwanted roll excursions are inevitable as they are caused by induced propeller torque, disturbances, and banking motion during turns. To estimate the manoeuvring performance of underwater vehicle, it is necessary to obtain the roll coefficient of body. This paper was covered estimation of roll coefficient of underwater vehicle using STAR-CCM+, commercial CFD(Computational Fluid Dynamics) code. The RANS equations for incompressible fluid flows was solved numerically by using a finite volume method. An MRF(Moving Reference Frame) Method was Also adopted for rotations of body. For the validation, the flow around a DARPA SUBOFF bare hull model was simulated and good agreement with experiments was obtained. And Pure roll coefficients were calculated and campared with the experimental data which were presented by Seoul National University. Finally, an underwater vehicle model with propeller was simulated and analyzed for estimation of roll coefficient variation caused by induced propeller torque.