• Steel and Composite Structures
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• v.45 no.4
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• pp.579-590
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• 2022

One of the biggest problems in structural steel calculation is the design of structures using the lowest possible material weight, making this a slow and costly process. To achieve this objective, several optimization methods have been developed and tested. Nevertheless, a method that performs very efficiently when applied to different problems is not yet available. Based on this assumption, this work proposes a hybrid metaheuristic algorithm for geometric and dimensional optimization of space trusses, called Simulated Squirrel Search Algorithm, which consists of an association of the well-established neighborhood shifting algorithm (Simulated Annealing) with a recently developed promising population algorithm (Squirrel Search Algorithm, or SSA). In this study, two models are tried, being respectively, a classical model from the literature (25-bar space truss) and a roof system composed of space trusses. The structures are subjected to resistance and displacement constraints. A penalty function using Fuzzy Logic (FL) is investigated. Comparative analyses are performed between the Squirrel Search Algorithm (SSSA) and other optimization methods present in the literature. The results obtained indicate that the proposed method can be competitive with other heuristics.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.288-294
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• 2013

The diagnosis of motor failures using an on-line method has been the aim of many researchers and studies. Several spectral analysis techniques have been developed and are used to facilitate on-line diagnosis methods in industry. This paper discusses the first application of a motor flux spectral analysis to the identification of broken rotor bar (BRB) faults in induction motors using a multiple signal classification (MUSIC) technique as an on-line diagnosis method. The proposed method measures the leakage flux in the radial direction using a radial flux sensor which is designed as a search coil and is installed between stator slots. The MUSIC technique, which requires fewer number of data samples and has a higher detection accuracy than the traditional fast Fourier transform (FFT) method, then calculates the motor load condition and extracts any abnormal signals related to motor failures in order to identify BRB faults. Experimental results clearly demonstrate that the proposed method is a promising candidate for an on-line diagnosis method to detect motor failures.

• Proceedings of the ESK Conference
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• 1997.10a
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• pp.168-176
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• 1997

The purpose of this study is to know load for each human body's knee joint to endure load efficiently, when weight lifter pulls suitable bar in the each weight lifting level. To use the difference of load and correlation between men and women, the conclusion of this stduy is to find parameters to conduct maximum limitation of maximum load to search maximum limitation. The moment of each joint in the lower area was to have a much difference between group of the turunk in the first step. It decreased rapidly until decent and greatly pulled in the second step. Neuromusclar moment increased suddenly in the decrease phase. This phenomenon resulted from shock-absorbing function to sbsorb a load from bar.

• Journal of the Korea Safety Management & Science
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• v.7 no.4
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• pp.85-99
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• 2005

The main objective of this paper is to search whether containment vessel's best pressure may increase until how long when loss of coolant accident (LOCA) happened in containment vessel of Ulchin nuclear power plant 1 and 2. Another goal of this research is to find the influential factors that increase containment vessel pressure. Model for this research is Ulchin nuclear power plant 1 with 10 cycles. Data were collected by simulator of Ulchin nuclear power plant 1 and design of experiment was used for data analysis. For the experiment, seven factors that are going to influence in containment vessel pressure were chosen. It was found that fatter which influences in early rise of containment vessel pressure after LOCA is only explosion size. Also, containment vessel's best pressure (3.74 bar.a) was much lower than limit (4.86 bar.a) of FSAR (Final Safety Analysis Report).

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.384-388
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• 2016

This paper proposed a m.Sketch to search the optimal link lengths for a legged walking robot. In order to apply the m.Sketch for the proposed, set the design parameters of the constraints and use the m.Skecth to get optimal GL(Groud Length) and GAC(Ground Angle Coefficient). The legged robot designed based on four-bar linkage theory and Theo Jansen mechanism. The stride length of the legged walking robot was defined based on the proposed kinematic analysis. Use the Edison Design m.Sketch simulate and find the optimal link length having the best of the Ground Length (GL) and Ground Angle Coefficient(GAC). And use these length implemented the Theo Jansen mechanism both in Science box parts and acrylic. In addition to the further expansion of the legs to reach the goaltranslating heavy objects or person.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.10a
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• pp.32-39
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• 2000

Probabilistic structural design optimization, which is characterized by the so-called probabilistic. constraints which introduce permissible probability of violation, is preferred to deterministic design optimization since unpredictable inherent uncertainties and randomness in structural and environmental properties are to be taken quantitatively into account by probabilistic design optimization. In this paper, the well-known reliability index based MPFP(Most Probable Failure Point) search approach and the newly introduced target performance measure based MPTP(Minimum Performance Target Point) search approach are summarized and compared. The present comparison focuses on the number of iterations required for the estimation of probabilistic constraints and a technique for improvement which removes exhaustive iterations is presented as well. A 10 bar truss problem is examined for this.

• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.1465-1468
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• 2007

지식정보화 시대의 많은 정보가 온라인에 공개되면서 다양한 형태의 검색 서비스가 여러 사이트를 통해서 제공됨에 따라 사용자는 목적에 따라 여러 사이트를 방문하여 원하는 정보를 검색하고 있다. 그동안 검색 서비스 제공자는 사용자의 접근성을 향상시키고 이용용이성을 제공하기 위해 여러 가지 검색창을 제공하였지만 변경된 서비스 정책이 유연하게 반영되지 않아 장기적으로 사용되지 못하였다. 본 논문에서는 기존 검책창 구조의 한계점을 극복하여 사용자 측면에서 간편하게 설치하면서, 제공자의 서비스 제공 정책에 따라 비즈니스 로직을 수정할 수 있는 검색창을 설계 구현하여 적용하였다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.4
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• pp.1-9
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• 2014

With the development of quantum computer, the development of the quantum-inspired search method applying the features of quantum mechanics and its application to engineering problems have emerged as one of the most interesting research topics. This algorithm stores information by using quantum-bit superposed basically by zero and one and approaches optional values through the quantum-gate operation. In this process, it can easily keep the balance between the two features of exploration and exploitation, and continually accumulates evolutionary information. This makes it differentiated from the existing search methods and estimated as a new algorithm as well. Thus, this study is to suggest a new minimum weight design technique by applying quantum-inspired search method into structural optimization of planar truss. In its mathematical model for optimum design, cost function is minimum weight and constraint function consists of the displacement and stress. To trace the accumulative process and gathering process of evolutionary information, the examples of 10-bar planar truss and 17-bar planar truss are chosen as the numerical examples, and their results are analyzed. The result of the structural optimized design in the numerical examples shows it has better result in minimum weight design, compared to those of the other existing search methods. It is also observed that more accurate optional values can be acquired as the result by accumulating evolutionary information. Besides, terminal condition is easily caught by representing Quantum-bit in probability.

• ETRI Journal
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• v.38 no.2
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• pp.326-336
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• 2016

We propose and describe new error control algorithms for redundant residue number systems (RRNSs) and residue number system product codes. These algorithms employ search techniques for obtaining error values from within a set of values (that contains all possible error values). For a given RRNS, the error control algorithms have a computational complexity of $t{\cdot}O(log_2\;n+log_2\;{\bar{m}})$ comparison operations, where t denotes the error correcting capability, n denotes the number of moduli, and ${\bar{m}}$ denotes the geometric average of moduli. These algorithms avoid most modular operations. We describe a refinement to the proposed algorithms that further avoids the modular operation required in their respective first steps, with an increase of ${\lceil}log_2\;n{\rceil}$ to their computational complexity. The new algorithms provide significant computational advantages over existing methods.

• Smart Media Journal
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• v.5 no.1
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• pp.104-113
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• 2016

A new design method for multi-functional pull-down menu based on stacking rules is proposed. The importance of a design point of view has been emphasized in many previous studies on web navigation. Taking technical aspects with an emphasis on programming techniques into consideration in this paper, multiple elements, which are used for constructing main menu of the pull-down menu, are capable of performing their unique functions independently in addition to basic classification function by disposing them to separated layers using stacking rules. Furthermore, the improvement of visual effects and efficiency for information navigation can be expected by implementing submenu selection-bar using animation techniques and function to automatically search submenu item. Finally, the effectiveness of the proposed method is identified by implementing multi-functional pull-down menu using CSS and jQuery.