• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2145-2157
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• 2018

Congestion Management (CM) is an attractive research area in the electrical power transmission with the power compensation abilities. Reconfiguration and the Flexible Alternating Current Transmission Systems (FACTS) devices utilization relieve the congestion in transmission lines. The lack of optimal power (real and reactive) usage with the better transfer capability and minimum cost is still challenging issue in the CM. The prediction of suitable place for the energy resources to control the power flow is the major requirement for power handling scenario. This paper proposes the novel optimization principle to select the best location for the energy resources to achieve the real-reactive power compensation. The parameters estimation and the selection of values with the best fitness through the Symmetrical Distance Travelling Optimization (SDTO) algorithm establishes the proper controlling of optimal power flow in the transmission lines. The modified fitness function formulation based on the bus parameters, index estimation correspond to the optimal reactive power usage enhances the power transfer capability with the minimum cost. The comparative analysis between the proposed method with the existing power management techniques regarding the parameters of power loss, cost value, load power and energy loss confirms the effectiveness of proposed work in the distributed renewable energy systems.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.3
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• pp.308-313
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• 2015

In this research, a multi-objective optimal design of a scroll compressor lower frame was approximated, and the design parameters of the lower frame were selected. The sensitivity of the design parameters was induced through a parameter analysis, and the thickness was determined to be the most sensitive parameter to stress and deflection. All of the design parameters regarding the mass are sensitive factors. It was formulated for the problem about stress and deflection to be caused by the axial load. The sensitivity of the design variables was determined using an orthogonal array for the parameter analysis. Using the central composite and D-optimal designs, a second polynomial approximation of the objective and constraint functions was formulated and the accuracy was verified through an R-square. These functions were applied to the optimal design program (NSGA-II). Through a CAE analysis, the effectiveness of the central composite and D-optimal designs was determined.

• Korean Journal of Veterinary Research
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• v.47 no.2
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• pp.247-254
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• 2007

This study was performed to identify the normal anatomic orientation of pulmonary arteries and to obtain the normal baseline parameters and the optimal contrast material delivery methods of computed tomographic pulmonary angiography (CTPA) on normal beagle dogs. Based on the contrast injection flow rate, the contrast volume, and the administration methods, the experimental groups were divided into 4 groups such as group 1 : 2 ml/s, 3 ml/kg, and monophasic administration; group 2 : 5 ml/s, 3 ml/kg, and monophasic administration; group 3 : 5 ml/s, 4 ml/kg, and monophasic administration; group 4 : 5 ml/s and 2 ml/kg in first phase, 0.3 ml/s and 2 ml/kg in second phase, as biphasic administration. Normal anatomic orientation of pulmonary arteries in CTPA was evaluated through reformatted and 3D images after retro-reconstruction. Normal parameters for great arteries and peripheral pulmonary arteries were obtained on the factor of basement hounsfield unit (HU) values, contrast enhanced HU values, delay time, and peak time. And the optimal contrast delivery methods were evaluated on the factor of contrast enhanced HU values, image quality, and artifact. The monophasic administration with 5 ml/s contrast injection flow rate and 3 ml/kg contrast volume was optimal in canine CTPA.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.6
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• pp.504-510
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• 2016

Robots are widely utilized in many fields, and various demands need customized robots. This study proposes an optimal design method based on swarm intelligence for selecting the kinematic parameter of a manipulator according to the task space trajectory desired by the user. The optimal design method is dealt with herein as an optimization problem. This study is based on swarm intelligence-based optimization algorithms (i.e., ant colony optimization (ACO) and particle swarm optimization algorithms) to determine the optimal kinematic parameters of the manipulator. The former is used to select the optimal kinematic parameter values, whereas the latter is utilized to solve the inverse kinematic problem when the ACO determines the parameter values. This study solves a design problem with the PUMA 560 when the desired task space trajectory is given and discusses its results in the simulation part to verify the performance of the proposed design.

• Fisheries and Aquatic Sciences
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• v.26 no.9
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• pp.525-534
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• 2023

Vitamin C plays an important role for fish survival, growth and disease resistance. However, the optimal vitamin C for rearing red drum Sciaenops ocellatus juveniles in Vietnam is not known. To address this issue, a 70-day feeding trial was conducted to evaluate the optimal dietary vitamin C requirements for red drum juveniles. Seven isonitrogenous (55.35% protein) and isolipidic (9.07% lipid) diets were formulated to include graded vitamin C concentrations of 23.2, 124.5, 235.2, 423.8, 626.7, 824.6, and 1,027.3 mg/kg, respectively. The results showed that fish fed on 423.8 mg/kg vitamin C diet had the highest growth rate, which can be linked to the increased feed utilization. Broken-line analysis indicated that the optimal dietary vitamin C requirements of red drum juveniles were 342.92 and 405.80 mg/kg for growth parameters, feed utilization, body composition and biochemical parameters of serum. Based on these parameters the optimal vitamin C supplementation level for red drum juveniles was estimated in the range of 342.92-405.80 mg/kg vitamin C in the diets with direct applications in producing artificial feed for rearing juveniles of this species in Vietnam.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.10
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• pp.1854-1862
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• 2006

The numerical methods of finding out the optimal position of optical phase conjugator (OPC) and the optimal fiber dispersions are prosed, which are able to effectively compensate overall channels in $8{\times}40Gbps$Gbps WDM system with non zero - dispersion shifted fiber (NZ-DSF) as an optical fiber. And BER characteristics in the system with two induced optimal parameters are compared with those in the system with the currently used mid-span spectral inversion (MSSI) in order to confirm the availability of the proposed methods. It is confirmed that the applying two induced optimal parameters into WDM system contribute to reduce power penalty to 4 times than that of WDM system with the conventional MSSI. Thus, the methods proposed in this research will be expected to alternate with the method of making a symmetrical distribution of power and local dispersion in real optical link which generates a serious problem if it was not made but it is the condition in the case of applying the OPC into multi-channels WDM system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.361-364
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• 2006

The numerical methods of finding the optimal position of optical phase conjugator (OPC) and the optimal fiber dispersions are proposed, which are able to effectively compensate overall channels in $8\times40$ Gbps WDM system with non zero - dispersion shifted fiber (NZ-DSF) as an optical fiber. And BER characteristics in the system with two induced optimal parameters are compared with those in the system with the currently used mid-span spectral inversion (MSSI) in order to confirm the availability of the proposed methods. It is confirmed that the applying two induced optimal parameters into WDM system contribute to reduce power penalty to 4 times than that of WDM system with the conventional MSSI.

• Structural Engineering and Mechanics
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• v.56 no.6
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• pp.959-982
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• 2015

In this study, a non-stationary random earthquake Clough-Penzien model is used to describe earthquake ground motion. Using stochastic direct integration in combination with an equivalent linear method, a solution is established to describe the non-stationary response of lead-rubber bearing (LRB) system to a stochastic earthquake. Two parameters are used to develop an optimization method for bearing design: the post-yielding stiffness and the normalized yield strength of the isolation bearing. Using the minimization of the maximum energy response level of the upper structure subjected to an earthquake as an objective function, and with the constraints that the bearing failure probability is no more than 5% and the second shape factor of the bearing is less than 5, a calculation method for the two optimal design parameters is presented. In this optimization process, the radial basis function (RBF) response surface was applied, instead of the implicit objective function and constraints, and a sequential quadratic programming (SQP) algorithm was used to solve the optimization problems. By considering the uncertainties of the structural parameters and seismic ground motion input parameters for the optimization of the bearing design, convex set models (such as the interval model and ellipsoidal model) are used to describe the uncertainty parameters. Subsequently, the optimal bearing design parameters were expanded at their median values into first-order Taylor series expansions, and then, the Lagrange multipliers method was used to determine the upper and lower boundaries of the parameters. Moreover, using a calculation example, the impacts of site soil parameters, such as input peak ground acceleration, bearing diameter and rubber shore hardness on the optimization parameters, are investigated.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1092-1094
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• 2009

The purpose of the research was to figure out the optimal binocular parallax inducing the least 3D visual fatigue. Subjective 3D visual fatigue was measured while the revolution depth and the average depth of an object were manipulated. The optimal binocular parallax was figured out by using data fitting method.

• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.346-350
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• 2009

Natural state materials contain a lot of available nutrient components. Among them, natural nutrient substances are utilized not only as the ingredient of functional foods but also as the excipients of functional cosmetics and pharmaceutic. Of these nutrient substances, solubility parameters of each components were calculated to choose the most suitable solvents for solutions. The solubility parameters for each components were composed of the dispersion contribution of the molecular attractive function, the polar contribution of the molecular attractive function and the contribution of the hydrogen bonding force. The chi parameters ($\chi_{12}$) were calculated with the information of the solubility parameter for the solute and solvent and were used as the criteria for the optimal solute-solvent pair. The optimal solvents were suggested with the numerical values of chi parameters for some amino acids.