• International Journal of Control, Automation, and Systems
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• v.5 no.2
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• pp.192-199
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• 2007

This paper proposes a new printed circuit board (PCB) assembly planning method for multi-head surface mounters. We present an integer programming formulation for the optimization problem, and propose a heuristic method to solve the large NP-complete problem within a reasonable time. A dynamic programming technique is then applied to the feeder arrangement optimization and placement sequence optimization to reduce the overall assembly time. Comparative simulation results are finally presented to verify the usefulness of the proposed method.

• IE interfaces
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• v.12 no.2
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• pp.337-345
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• 1999

This paper presents the optimization of a drilling operation subject to machining constraints such as power, torque, thrust, speed and feed rate. The optimization is meant to minimize the machining time required to produce a hole. For the first time, the effects of a pilot hole are included in the formulation of the machining constraints. The optimization problem is solved by using the geometric programming technique. The dual problem is simplified based on the characteristics of the problem, and the effects of machining constraints on the machining variables are identified.

• International Journal of Control, Automation, and Systems
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• v.6 no.3
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• pp.401-412
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• 2008

This paper discusses a design methodology of cooperative path planning for dynamical multi-agent systems with spatial and temporal constraints. The cooperative behavior of the multi-agent systems is specified in terms of the objective function in an optimization formulation. The path of achieving cooperative tasks is then generated by the optimization formulation constructed based on a differential flatness approach. Three scenarios of multi-agent tasking are proposed at the cooperative task planning framework. Given agent dynamics, both spatial and temporal constraints are considered in the path planning. The path planning algorithm first finds trajectory curves in a lower-dimensional space and then parameterizes the curves by a set of B-spline representations. The coefficients of the B-spline curves are further solved by a sequential quadratic programming solver to achieve the optimization objective and satisfy these constraints. Finally, several illustrative examples of cooperative path/task planning are presented.

• Computers and Concrete
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• v.3 no.5
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• pp.313-334
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• 2006

A novel formulation aiming to achieve optimal design of reinforced concrete (RC) structures is presented here. Optimal sizing and reinforcing for beam and column members in multi-bay and multistory RC structures incorporates optimal stiffness correlation among all structural members and results in cost savings over typical-practice design solutions. A Nonlinear Programming algorithm searches for a minimum cost solution that satisfies ACI 2005 code requirements for axial and flexural loads. Material and labor costs for forming and placing concrete and steel are incorporated as a function of member size using RS Means 2005 cost data. Successful implementation demonstrates the abilities and performance of MATLAB's (The Mathworks, Inc.) Sequential Quadratic Programming algorithm for the design optimization of RC structures. A number of examples are presented that demonstrate the ability of this formulation to achieve optimal designs.

• Journal of Computational Design and Engineering
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• v.2 no.3
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• pp.157-164
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• 2015

This paper discusses an optimization-based approach for the design of a product platform for industrial three-axis linear-type robots, which are widely used for handling objects in manufacturing lines. Since the operational specifications of these robots, such as operation speed, working distance and orientation, weight and shape of loads, etc., will vary for different applications, robotic system vendors must provide various types of robots efficiently and effectively to meet a range of market needs. A promising step toward this goal is the concept of a product platform, in which several key elements are commonly used across a series of products, which can then be customized for individual requirements. However the design of a product platform is more complicated than that of each product, due to the need to optimize the design across many products. This paper proposes an optimization-based fundamental framework toward the design of a product platform for industrial three-axis linear-type robots; this framework allows the solution of a complicated design problem and builds an optimal design method of fundamental features of robot frames that are commonly used for a wide range of robots. In this formulation, some key performance metrics of the robot are estimated by a reducedorder model which is configured with beam theory. A multi-objective optimization problem is formulated to represent the trade-offs among key design parameters using a weighted-sum form for a single product. This formulation is integrated into a mini-max type optimization problem across a series of robots as an optimal design formulation for the product platform. Some case studies of optimal platform design for industrial three-axis linear-type robots are presented to demonstrate the applications of a genetic algorithm to such mathematical models.

• Food Engineering Progress
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• v.15 no.4
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• pp.297-304
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• 2011

Ramen flour formulation was optimized by applying a mixture experimental design. In the optimization, the overall palatability (OP) of cooked ramen and the rheological properties of selected dough were maximized or minimized. Blended ratios of the ingredients such as Dark Northern Spring (DNS), Hard Red Winter (HRW), and Soft White (SW) were designed on a simplex-lattice. Dough rheological properties were measured by Rapid Visco Analyser (RVA), Farinograph, and Extensograph, and the overall palatability by sensory evaluation. Several principal dough rheological properties such as RVA peak viscosity (PV), Farinograph development time (DT), and Extensograph resistance/extensibility after 45 min (R/E 45 min) were selected to influence the overall palatability by canonical correlation analysis (CCA). Goals of the optimization were given as OP maximized, PV maximized, DT minimized, and R/E at 45 min maximized. The optimization results were found to be DNS 33.3%, HRW 33.3%, and SW 33.3% with OP, 5.825; PV, 587.9 cP; DT, 3.1 min; R/E at 45 min, 2.339 BU/mm.

• Journal of Pharmaceutical Investigation
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• v.28 no.4
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• pp.267-274
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• 1998

Biphenyl dimethyl dicarboxylate (DDB) has been used for the treatment of acute and chronic hepatitis. However, its poor solubility in water, $2.5\;{\mu}g/ml$, caused low bioavailability of the drug after its oral administration. In order to increase the dissolution of DDB in gastrointestinal tracts, consequently to increase the bioavailability of the drug, DDB tablet was prepared with solid dispersion of DDB with poloxamer 338 or 407 using a direct compression method. To improve the flowability of the solid dispersion, Aerosil was used as an adsorbent. The effect of formulation variables (poloxamer and Aerosil contents) on the dissolution rate of DDB from tablets was investigated using an analysis of variance. The dissolution rate of DDB from tablets was evaluated with KP II (paddle) method. The dissolution patterns of the drug from the tablet prepared with poloxamer 407 were affected significantly by the contents of poloxamers and Aerosil over the range employed, but those of the drug from the tablet prepared with poloxamer 338 were not. The optimum formulation of the DDB tablet, showed the same dissolution pattern as that of the reference, was obtained after polynomial equations of drug dissolution profiles for each formula were fitted to contour plots. The optimum formulation ratios of DDB:poloxamer 407:Aerosil were 1:2.5:2.5 and 1:5:5.

• Computational Structural Engineering
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• v.7 no.1
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• pp.117-124
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• 1994

Multi-level Multi-objective optimization(MLMO) for reinforced concrete framed structure is performed, and compared with the results of single-level single-objective optimization. MLMO method allows flexibility to meet the design needs such as deflection and cost of structures using weighting factors. Using Multi-level formulation, the numbers of constraints and variables are reduced at each levels, and the optimization formulation becomes simplified. The force approximation method is used to reflect the variation in design variables between the substructures, and thus coupling is maintained. And the linear approximated constraints and objective function are used to reduce the number of structural analysis in optimization process. It is shown that the developed algorithm with move limit can converge effectively to optimal solution.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.2 s.107
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• pp.115-123
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• 2006

A feasibility of using the topology optimization method for structural damage identification is investigated for the first time. The frequency response functions (FRFs) are assumed to be constructed by the finite element models of damaged and undamaged structures. In addition to commonly used resonances, antiresonances are employed as the damage identifying modal parameters. For the topology optimization formulation, the modal parameters of the undamaged structure are made to approach those of the damaged structure by means of the constraint equations, while the objective function is an explicit penalty function requiring clear black-and-white images. The developed formulation is especially suitable for damage identification problems dealing with many modal parameters. Although relatively simple numerical problems were considered in this investigation, the possibility of using the topology optimization method for structural damage identification is suggested through this research.

• Journal of Korean Society of Transportation
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• v.18 no.1
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• pp.87-97
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• 2000

Signal optimization model is divided bandwidth-maximizing model and delay-minimizing model. Bandwidth-maximizing model express model formulation as MILP(Mixed Integer Linear Programming) and delay-minimizing model like TRANSYT-7F use "hill climbing" a1gorithm to optimize signal times. This study Proposed optimization model using genetic algorithm one of evolution algorithm breaking from existing optimization model This Proposed model were tested by several scenarios and evaluated through NETSIM with TRANSYT-7F\`s outputs. The result showed capability that can obtain superior solution.