• Journal of Biomedical Engineering Research
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• v.26 no.6
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• pp.365-372
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• 2005

Topology optimization method has a great advantage and capability over a conventional shape optimization technique because it optimizes a topology as well as a shape and size of structure. The purpose of the present study, using topology optimization method with an objective function of minimum compliance as a mechanism of bone remodeling, is to examine which shape factors of femur is strongly related with the curvature of femoral shaft. As is expected, the optimized curvature increased definitely with neck angle among the shape factors and showed a similar trend with the measured curvature to neck angle. Therefore, the topology optimization method can be successfully applied in the analysis of bone remodeling phenomenon in the subsequent studies.

• KSTLE International Journal
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• v.4 no.1
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• pp.31-36
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• 2003

Sliding and impact/sliding wear test in room temperature air and water were performed to evaluate the effect of spring shapes on the wear mechanism of a fuel rod. The main focus was to quantitatively compare the wear behavior of a fuel rod with different support springs (i.e. two concaves, a convex and a flat shape) using a ratio of wear volume to worn area (De)-The results indicated that the wear volumes at each spring condition were varied with the change of test environment and loading type. However, the relationship between the wear volume and worn area was determined by only spring shape even though the wear tests were carried out at different test conditions. From the above results, the optimized spring shape which has more wear-resistant could be determined using the analysis results of the relation between the variation of De and worn surface observations in each test condition.

• The KSFM Journal of Fluid Machinery
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• v.12 no.4
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• pp.7-13
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• 2009

The purposes of present work are to analyze the convective heat transfer with three-dimensional Reynolds-averaged Navier-Stokes analysis, and to optimize shape of the mixing vane using the analysis results. Response surface method is employed as an optimization technique. The objective function is defined as a combination of inverse of heat transfer rate and friction loss. Two bend angles of mixing vane are selected as design variables. Thermal-hydraulic performances have been discussed and optimum shape has been obtained as a function of weighting factor in the objective function. The results show that the optimized geometry improves the heat transfer performance far downstream of the mixing vane.

• The KSFM Journal of Fluid Machinery
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• v.10 no.6
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• pp.44-49
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• 2007

In this paper, effects of inlet shape on the performance of a submerged cargo pump were numerically studied using a commercial CFD code CFX. The inlet shape, especially the gap between pump and suction well, is an important parameter in a point of view of performances of submerged cargo pump due to its effects on the residual and also hydraulic performance of the pump, respectively. To know the optimized gap, the overall performance degradations were calculated with the gap. In addition to that, the flow field through the gap was investigated to explain the effect of velocity non-uniformity on the performance of the pump impeller.

• Journal of computational fluids engineering
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• v.14 no.2
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• pp.1-8
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• 2009

The purposes of present work are to analyze the convective heat transfer with three-dimensional Reynolds-averaged Navier-Stokes analysis, and to optimize shape of the mixing vane taken tolerance into consideration by using the analysis results. Response surface method is employed as an optimization technique. The objective function is defined as a combination of heat transfer rate and inverse of pressure drop. Two bend angles of mixing vane are selected as design variables. Thermal-hydraulic performances have been discussed and optimum shape has been obtained as a function of weighting factor in the objective function. The results show that the optimized geometry improves the heat transfer performance far downstream of the mixing vane.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.6
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• pp.133-139
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• 2000

Vibrational characteristics of the vehicle structure are mainly influenced by the shape of the pillar cross section. In this paper a vehicle structural optimization technique has been developed to investigate a lightweight vehicle structure subject to constraints on natural frequencies in a simple beam-and-shell model. In this technique, the optimization procedures involve two stages. In the first stage, the section procedures involve tow stages. In the first stage, the section properties of beam elements of the vehicle structure has been optimized to have minimum weight while satisfying the constraints of natural frequencies. And, in the second stage, the shape of the cross section of the elements of the structure has been determined.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.131-135
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• 2013

In this study, to develop a light weight duo type aluminum LPG tank in stead of a conventional steel tank optimization technology is used. Two types of optimization method are carried out for internal compression test simulation of a LPG tank. The first is the thickness only optimization of LPG tank components. The second is the thickness and shape optimization. For the case of the thickness only optimization the weight reduction rate of an optimized tank compare to that of the initial design is 42%. Also 48% weight reduction was achieved for the case of the thickness and shape optimization.

• Smart Structures and Systems
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• v.5 no.6
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• pp.645-662
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• 2009

Adaptive wings are capable of properly modifying their shape depending on the current aerodynamic conditions, in order to improve the overall performance of a flying vehicle. In this paper is presented the concept design of a small-scale compliant wing rib whose outline may be distorted in order to switch from an aerodynamic profile to another. The distortion loads are induced by shape memory alloy actuators placed within the frame of a wing section whose elastic response is predicted by the matrix method with beam formulation. Genetic optimization is used to find a wing rib structure (corresponding to the first airfoil) able to properly deforms itself when loaded by the SMA-induced forces, becoming as close as possible to the desired target shape (second airfoil). An experimental validation of the design procedure is also carried out with reference to a simplified structure layout.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.389-394
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• 2003

In this paper, a shape optimization technique is applied to design of an air-conditioner mounting bracket. The mounting bracket is a structural component of an engine, on which bolts attach an air-conditioner compressor. The air-conditioner mounting bracket has a large portion of weight among the engine components. To reduce weight of the bracket, the shape is optimized using a finite element software. The compressor assembly, composed of a compressor and a bracket is modeled using finite elements. An objective function for the shape optimization of the bracket is the weight of the bracket. Two design constraints on the bracket are the first resonant frequency of the compressor assembly and the fatigue life of the bracket. The design variables are the shape of the bracket including thickness profiles of the front and back surfaces of the bracket, radius of outer bolt-holes, and side edge profiles. The coordinates of the FE nodes control the shape parameters. Optimal shapes of the bracket are obtained by using SOL200 of MSC/NASTRAN.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.4
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• pp.1738-1756
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• 2020

To improve the accuracy and realism of the virtual surgical simulation system, this paper proposes an optimized mass-spring model with shape restoration ability based on volume conservation to simulate soft tissue deformation. The proposed method constructs a soft tissue surface model that adopts a new flexion spring for resisting bending and incorporates it into the mass-spring model (MSM) to restore the original shape. Then, we employ the particle swarm optimization algorithm to achieve the optimal solution of the model parameters. Besides, the volume conservation constraint is applied to the position-based dynamics (PBD) approach to maintain the volume of the deformable object for constructing the soft tissue volumetric model base on tetrahedrons. Finally, we built a simulation system on the PHANTOM OMNI force tactile interaction device to realize the deformation simulation of the virtual liver. Experimental results show that the proposed model has a good shape restoration ability and incompressibility, which can enhance the deformation accuracy and interactive realism.