• Journal of Digital Contents Society
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• v.18 no.1
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• pp.197-202
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• 2017

In this study, the current status of the South Korean performance facilities was analyzed, and then the key tasks for the improvement of such facilities were identified. The study results show that the country's performance facilities are disproportionately concentrated in the Seoul region whereas the lack of performance facilities per unit area in the other regional provinces considerably lowers the accessibility of such facilities to the local residents. As part of the measures to solve such problems, this study proposed the development of a system that would enable the optimal placement of such performance facilities. It also proposed the development of another system that can simulate and suggest an optimal performance type for a given region because the ultimate goal of this study was to raise the utilization rate and financial self-reliance of the performance facilities in South Korea.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.5
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• pp.381-389
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• 2014

This study is concerned with the estimation of vibration-field of a cylindrical structure by modal expansion method(MEM). MEM is a technique that identifies modal participation factors using some of vibration signals and natural modes of the structure: The selection of sensor locations has a big influence on predicted vibration results. Therefore, this paper deals with four optimal sensor placement( OSP) methods, EFI, EFI-DPR, EVP, AutoMAC, for the estimation of vibration field. It also finds optimal sensor locations of the cylindrical structure by each OSP method and then performs MEMs. Predicted vibration results compared with reference ones obtained by forced response analysis. The standard deviations of errors between reference and predicted results were also calculated. It is utilized to select the most suitable OSP method for estimation of vibration field of the cylindrical structure.

• Smart Structures and Systems
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• v.15 no.1
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• pp.191-207
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• 2015

Proper placement of sensors plays a key role in construction and implementation of an effective structural health monitoring (SHM) system. This paper proposes a novel methodology called the distributed monkey algorithm (DMA) for the optimum design of SHM system sensor arrays. Different from the existing algorithms, the dual-structure coding method is adopted for the representation of design variables and the single large population is partitioned into subsets and each subpopulation searches the space in different directions separately, leading to quicker convergence and higher searching capability. After the personal areas of all subpopulations have been finished, the initial optimal solutions in every subpopulation are extracted and reordered into a new subpopulation, and the harmony search algorithm (HSA) is incorporated to find the final optimal solution. A computational case of a high-rise building has been implemented to demonstrate the effectiveness of the proposed method. Investigations have clearly suggested that the proposed DMA is simple in concept, few in parameters, easy in implementation, and could generate sensor configurations superior to other conventional algorithms both in terms of generating optimal solutions as well as faster convergence.

• Structural Engineering and Mechanics
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• v.1 no.1
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• pp.119-135
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• 1993

The paper presents a generalized optimal active control algorithm for earthquake-resistant structures. The study included the weighting matrix configuration, stability, and time-delays for achieving control effectiveness and optimum solution. The sensitivity of various time-delays in the optimal solution is investigated for which the stability regions are determined. A simplified method for reducing the influence of time-delay on dynamic response is proposed. Numerical examples illustrate that the proposed optimal control algorithm is advantageous over others currently in vogue. Its feedback control law is independent of the time increment, and its weighting matrix can be flexibly selected and adjusted at any time during the operation of the control system. The examples also show that the weighting matrix based on pole placement approach is superior to other weighting matrix configurations for its self-adjustable control effectiveness. Using the time-delay correction method can significantly reduce the influence of time-delays on both structural response and required control force.

• The Journal of Advanced Prosthodontics
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• v.7 no.1
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• pp.76-84
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• 2015

This article reviews the topic of how to identify and develop a removable partial denture (RPD) path of placement, and provides a literature review of the concept of the RPD path of placement, also known as the path of insertion. An optimal RPD path of placement, guided by mutually parallel guide planes, ensures that the RPD flanges fit intimately over edentulous ridge structures and that the framework fits intimately with guide plane surfaces, which prevents food collecting empty spaces between the intaglio surface of the framework and intraoral surfaces, and ensures that RPD clasps engage adequate numbers of tooth undercuts to ensure RPD retention. The article covers topics such as the causes of obstructions to RPD intra-oral seating, the causes of food collecting empty spaces that may exist around an RPD, and how to identify if a guide plane is parallel with the projected RPD path of placement. The article presents a method of using a surgical operating microscope, or high magnification (6-8x or greater) binocular surgical loupes telescopes, combined with co-axial illumination, to identify a preliminary path of placement for an arch. This preliminary path of placement concept may help to guide a dentist or a dental laboratory technician when surveying a master cast of the arch to develop an RPD path of placement, or in verifying that intra-oral contouring has aligned teeth surfaces optimally with the RPD path of placement. In dentistry, a well-fitting RPD reduces long-term periodontal or structural damage to abutment teeth.

• Smart Media Journal
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• v.11 no.9
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• pp.75-80
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• 2022

Recently, research and development on immersive virtual reality(VR) technology to provide a realistic experience is being widely conducted. To provide realistic experience in immersive virtual reality for VR participants, virtual environments should consist of high-realistic environments using 3D reconstruction. In this paper, to acquire 3D information in real space using multiple cameras in the reconstruction process, we propose a novel method of optimal camera placement for accurate reconstruction to minimize distortion of 3D information. Through our approach in this paper, real 3D information can obtain with minimized errors during environment reconstruction, and it is possible to provide a more immersive experience with the created virtual environment.

• Transactions on Electrical and Electronic Materials
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• v.18 no.6
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• pp.345-349
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• 2017

Reconfiguration is an important method to minimize power loss and load interruption by creating an optimal configuration of a system. Furthermore, by increasing demand and value of consumption, construction of new power plants can be postponed in networks by reconfiguration and proper arrangement of linkage switches. This method is feasible for radial networks, which create meshes of linkage switches. One convenient way to achieve a system with minimal power loss and interruption is to utilize capacitors. Optimal placement and sizing of capacitors in such applications is an important issue in the literature. In this paper, cat swarm optimization is introduced as a new metaheuristic algorithm to achieve this purpose. Simulation has been carried out in two feasible networks, 69-bus and 33-bus systems.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.81-82
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• 2016

The present study aims to derive optimal interface treatment conditions for emulating a monolithic construction. The joints in this construction are formed through the bonding shear evaluation method during the placement of ultra-high-performance concrete (UHPC) and normal strength concrete (NSC). The evaluation items include push-off tests for homogeneous UHPC + UHPC and heterogeneous NSC + UHPC. The experimental samples comprised a monolithic placement as the baseline, two levels for the separated placement according to the compression strength of concrete, and five levels for the interface treatment. The increase in the number of grooves and their cross-sectional areas only slightly influenced the bonding shear performance. The optimal interface treatment method for the homogeneous UHPC + UHPC construction grooves was at least 30mm. The heterogeneous NSC + UHPC construction should utilize waterjet roughening to expose the aggregate for the increased roughness.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.164-171
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• 2008

This paper proposes the planning method for placement of capacitors in a distribution system. The main objectives in the planning for capacitor allocation are the reduction of installation costs and electric power loss. In the proposed method, the life time of each device is considered in calculating installation costs, and the optimal operation status of devices is found by genetic algorithm. Then, the optimal numbers and locations are determined based on the optimal operation status. Simulation results in the 69-bus distribution system show that the proposed method performs better than conventional methods.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.474-486
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• 2015

This paper proposes a multi-objective optimal placement method of Phasor Measurement Units (PMUs) in large electric transmission systems. It is proposed for minimizing the number of PMUs for complete system observability and maximizing measurement redundancy of the buses, simultaneously. The measurement redundancy of the bus indicates that number of times a bus is able to monitor more than once by PMUs set. A high level of measurement redundancy can maximize the system observability and it is required for a reliable power system state estimation. Therefore, simultaneous optimizations of the two conflicting objectives are performed using a binary coded firefly algorithm. The complete observability of the power system is first prepared and then, single line loss contingency condition is added to the main model. The practical measurement limitation of PMUs is also considered. The efficiency of the proposed method is validated on IEEE 14, 30, 57 and 118 bus test systems and a real and large- scale Polish 2383 bus system. The valuable approach of firefly algorithm is demonstrated in finding the optimal number of PMUs and their locations by comparing its performance with earlier works.