• 한국자동차공학회논문집
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• 제9권5호
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• pp.165-172
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• 2001

Wheel bearing units were almost exclusively used for car front wheel, where the two ball rows are directly side by side with integrated rubber seal. The seal is of important for wheel bearing units due to the adverse environmental conditions with mud and splash water. The seal of wheel bearing units was designed to have geometry with multi lips, which elastic lip contacts and deforms with bearing. The equation of reaction force for deformed lip as cantilever beam was previously used for seal lip design. But it's result was not useful because deflection of the beam differs from lip's. In this study, deformed shape of the lip was assumed to and order function which is more similar to lip deformation and made the equation for reaction force prediction. The Reaction forces from each other equations were compared with results by FEA to prove usefulness of new equation.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2001년도 춘계학술대회 논문집
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• pp.77-80
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• 2001

IC lead frame needs the precision shape for good efficiency. In the blanking process, there are many parameter effected the dimensional accuracy : lead width, blanking order, striper force, tool clearance etc. In this research, the4 undesirable defects appeared in the final blanking process. so we measured the deflection of lead according to the stripper force using $PAM-STAMP_{TM}$. In the result, the deflection was decreased by increasing the stripper force properly. and we changed the blanking order on the test model. In the blanking order, deflection is good from the outer line position blanking to center line position. so we can design the precision die without tryout by the prediction of the lead deflection.

• 한국정밀공학회지
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• 제15권2호
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• pp.146-153
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• 1998

NC machines with 4 or 5 axes are capable of various tool approach motions, which makes interference-free and high machinablity machining possible. This paper deals with how to integrate these two advantages (interference-free and high machinability machining) in multi-axes NC machining with a ball-end mill. Feasible tool approach region at a point on a surface is first computed, then among which an approach direction is determined so as to minimize the cutting force required. Tool and spindle volumes are considered in computing the feasible tool approach region, and the computing time is improved by trans-forming surface patches into minimal enclosing spheres. A cutting force prediction model is used for estimating the cutting force. The algorithm is developed so as to be applied to 4- or 5-axes NC machining in common.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
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• pp.153-162
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• 2004

The force profile from strip to work roll is very important factor in deformation of roll. But It is not easy to predict the profile because strip crown affect its tendency. From finite element method result, some assumptions can be obtained and the roll force profile model is derived. Also the tension profile and lateral strain are derived. The prediction accuracy of the proposed model is examined through comparison with finite element calculation result.

• 한국정밀공학회지
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• 제16권4호통권97호
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• pp.229-236
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• 1999

The surface, generated by end milling operation, is deteriorated by tool runout, vibration, tool wear and tool deflection, etc. Among them, the effect of tool deflection on surface accuracy is analyzed. Surface generation model for the prediction of the topography of machined srufaces has been developed based on cutting mechanism and cutting tool geometry. This model accounts for not only the ideal geometrical surface, but also the deflection of tool due to cutting force. For the more accurate prediction of cutting force, flexible end mill model is used to simulate cutting process. Computer simulation has shown the feasibility of the surface generation system. Using developed simulation system, the relations between the shape of end mill and cutting conditions are analyzed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.31-35
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• 2001

Slopping deteriorates the productivity and the stability of operation in BOF refining process, and hence POSCO has developed methods to predict and prevent slopping. Specific equipment was developed to measure the change of the reacting force to the oxygen-blowing lance against oxygen jet and the force was gathered and analyzed with the flow rate of oxygen and the height of lance. From this study, it was found that the reacting force is strongly correlated to the slag foam height. Currently, the modeling of the relation of the slag foaming level and the vertically acted force to lance is being approached for predicting the slopping.

• 소음진동
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• 제2권4호
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• pp.273-280
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• 1992

The prediction of vibration response of floor is necessary in order to check whether the floor vibration level will satisfy the allowable vibration standard of precise machinery such as electronic microscopes in semiconductor manufacturing plant before the installation of various neighboring equipment facility. In conventional vibration isolation, we were mainly interested in minimization of vibration transmissibility and stabilization of vibration isolation system. But in order to predict vibration response of floor, it is necessary to know exciting force of equipment installed on the floor and the mobility of the floor. We measured the exciting force of the dropped mass assumed as equipment and the mobility of some practical building floor using large impact hammer. And from this we predicted the vibration response of floor on which the mass dropped. This predicted vibration response of floor is compared with measured vibration response. Through upper procedure, we examined the possibility of predicting vibration response of floor from the information of exciting force of equipment and the mobility of floor.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.1055-1060
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• 2001

Springing phenomena of ships is introduced with its concept, research history and approach methodology. Being a hydroelasticity problem, non-linear vibration and stochastic process, springing was formulated and modeled in vibration point of view separating hydrodynamic force into system properties and excitation force. Both RAO and response spectrum as well as wave spectrum were presented as a case study of springing analysis for a flexible vessel with wide breadth. The effect of advance speed, heading angle and loading condition were investigated as parametric study. The results and observations showed availability of analysis for the prediction of the ship springing behavior.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1653-1654
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• 2013

• International Journal of Naval Architecture and Ocean Engineering
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• 제8권6호
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• pp.589-601
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• 2016

The hybrid grid was adopted and numerical prediction analysis of propeller unsteady bearing force considering free surface was performed for mode and full-scale KCS hull-propeller-rudder system by employing RANS method and VOF model. In order to obtain the propeller velocity under self-propulsion point, firstly, the numerical simulation for self-propulsion test of full-scale ship is carried out. The results show that the scale effect of velocity at self-propulsion point and wake fraction is obvious. Then, the transient two-phase flow calculations are performed for model and full-scale KCS hull-propeller-rudder systems. According to the monitoring data, it is found that the propeller unsteady bearing force is fluctuating periodically over time and full-scale propeller's time-average value is smaller than model-scale's. The frequency spectrum curves are also provided after fast Fourier transform. By analyzing the frequency spectrum data, it is easy to summarize that each component of the propeller bearing force have the same fluctuation frequency and the peak in BFP is maximum. What's more, each component of full-scale bearing force's fluctuation value is bigger than model-scale's except the bending moment coefficient about the Y-axis.