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This paper first proposes a novel concept of differential evolution (DE) with an automatic parameter adjustment that controls its search situation to be a promising situation by the error feedback. It is called feedback-controlled differential evolution (FCDE), whose adjustment mechanism consists of three parts: Evaluator, Referencer, and Controller. Evaluator calculates an evaluation index which measures the search situation. Referencer generates a reference index being a target of the evaluation index which corresponds to a promising situation. Controller operates the parameters to make the evaluation index follow the reference index using its error feedback. Further, this paper realizes a method in FCDE for a typical DE called 'DE/best/1/bin" by designing the three parts. The effectiveness of the proposed method is confirmed through various computational experiments from the viewpoints of controllability and performance. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

SUMMARY Differential evolution (DE) is an effective optimization method for global continuous optimization problems. Recently, we developed local descent direction vector based differential evolution (LDDVDE), which uses local descent direction vectors based on the operation vectors in order to improve the local search performance of DE. In this paper, we extend LDDVDE to multiobjective optimization problems. We adopt the hyper-volume indicator to order the operation vectors to make the local descent direction vectors for the case of multiobjective optimization problems. The effectiveness of the proposed method is confirmed through some numerical experiments for typical benchmark problems. [ABSTRACT FROM AUTHOR]

Particle swarm optimization (PSO) is one of the most powerful methods for solving unconstrained and constrained global optimization problems. A cluster-structured PSO with interaction and adaptation is proposed in this paper, and the cluster structure, interaction, and adaptation of the proposed PSO are analyzed by numerical simulations. The feasibility and advantages of the proposed cluster-structured PSO are demonstrated by numerical simulations using some typical global optimization test problems. © 2011 Wiley Periodicals, Inc. Electron Comm Jpn, 94(11): 9-17, 2011; Published online in Wiley Online Library (). DOI 10.1002/ecj.10379 [ABSTRACT FROM AUTHOR]

This paper presents a new form of Particle Swarm Optimization (PSO) based on the concept of tabu search (TS). In PSO, when a particle finds a local optimal solution, all of the particles gather around that one, and cannot escape from it. On the other hand, TS can escape from the local optimal solution by moving away from the best present solution. The proposed Tabu List PSO (TL-PSO) is a method for combining the strong points of PSO and TS. This method stores the history of pbest in a tabu list. When a particle has a reduced searching ability, it selects a pbest of the past from the historical values, which is used for the update. This makes each particle active, and the searching ability of the swarm makes progress. The proposed method was validated by numerical simulations with several functions that are well known as optimization benchmark problems for comparison to the conventional PSO method. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(4): 31–37, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20966 [ABSTRACT FROM AUTHOR]

To study an environmental or biological solution, it is essential to separate its constituents. In this study, a 3D-deformable dynamic microfilter was developed to selectively separate the target substance from a solution. This microfilter is a fine metallic nickel structure fabricated using photolithography and electroplating techniques. It is gold-coated across its entire surface with multiple slits of 10–20 μm in width. Its two-dimensional shape is deformed into a three-dimensional shape when used for fluid separation due to hydrodynamic forces. By adjusting the pressure applied to the microfilter, the size of the gap created by deformation can be changed. To effectively isolate the target substance, the relationship between the solution flow rate and the extent of microfilter deformation was investigated. The filtration experiments demonstrated the microfilter's ability to isolate the target substance with elastic deformation without undergoing plastic deformation. Additionally, modification of the microfilter surface with nucleic acid aptamers resulted in the selective isolation of the target cell, which further demonstrates the potential application of microfilters in the isolation of specific components of heterogeneous solutions. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the properties of the superior solution set search (SSSS) problem and point out the structural similarities between it and the multiobjective optimization problem. Based on the analyzed properties, we propose a new Firefly algorithm (FA) based on superior relations, which can search for the superior solution set by using the user's quantitative desire level as a search strategy. By introducing the distance of the problem space into the moving mechanism, FA makes it possible to search for multiple local optimal solutions by dividing the solution set into multiple groups. By analyzing this property of FA, we clarify the affinity between FA and the SSSS problem. We subsequently analyze the SSSS problem and FA, and discuss their properties together in a similar problem setting. We propose an FA based on superior relations as a new optimization technique for the superior solution set problem based on these analyses. Numerical experiments are then conducted using the SSSS problem and demonstrate the usefulness of the proposed method by comparing the performance of the proposed method with the conventional FA. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

In conventional single‐objective optimization, presenting multiple alternatives is difficult because the aim is to search for only one global optimal or suboptimal solution. In this paper, we propose a superior solution set search problem as an optimization problem to simultaneously find multiple excellent solutions in multimodal functions. In addition, we analyze the characteristics of the Firefly Algorithm (FA), which divides the search process into multiple clusters, and using this property, we efficiently search for the superior solution set. We interpret the metaheuristics strategy (i.e., diversification and intensification) of the superior solution set search problem and clarify the effects of parameters on the cluster search dynamics of FA in terms of the metaheuristics strategy. After the above analysis, we propose an adaptive FA that preliminarily performs parameter adjustment according to set target value schedule, evaluate indicators of diversification and intensification for the superior solution set search problem, and verify their usefulness by conducting a numerical experiment using three typical benchmark functions. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

In this study, we show the lack of rotational invariance in the Artificial Bee Colony algorithm (ABC) through numerical experiments. After analysis from the viewpoint of rotational invariance, we develop an ABC with rotational invariance using a hypersphere. The performance of the proposed ABC with rotational invariance is verified through numerical experiments for typical separable benchmark functions without and with rotation. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

SUMMARY In this paper, we introduce a new concept of hierarchical structure into solution space of a combinatorial optimization problem, and develop a novel combinatorial optimization method based on the concept. The introduction of the above new hierarchical structure concept 'basin of attraction,' which is a set binding solution by utilizing properties of local optimal solutions, enables us to construe solution space as not only set of solutions but also set of basins of attraction hierarchically. It is well known that the appropriate balance of two policies, intensification and diversification, is essential in the search of metaheuristics. The proposed method clarifies the search policy by relating the hierarchical structure in solution space with intensification and diversification. With regard to diversification, we incorporate a movement strategy that has longer term or more macroscopic viewpoint than before in the algorithm by utilizing the concept basin of attraction. The performance of the proposed combinatorial optimization method is inspected by numerical experiments using some typical benchmark problems of a traveling salesman problem, a knapsack problem, a flow-shop scheduling problem, and a quadratic assignment problem. [ABSTRACT FROM AUTHOR]

A super-distributed energy system is a future energy system in which a large part of its demand is fed by a huge number of distributed generators. At one time some nodes in the super-distributed energy system behave as load, whereas at other times they behave as generator—the characteristic of each node depends on the customers' decision. In such situation, it is very difficult to regulate the voltage profile over the system due to the complexity of power flows. This paper proposes a novel control method of distributed generators that can achieve autonomous decentralized voltage profile regulation by using multi-agent technology. The proposed multi-agent system employs two types of agent: a control agent and a mobile agent. Control agents generate or consume reactive power to regulate the voltage profile of neighboring nodes and mobile agents transmit the information necessary for VQ-control among the control agents. The proposed control method is tested through numerical simulations. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(4): 43–52, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20484 [ABSTRACT FROM AUTHOR]

Cancer cell count in the blood of cancer patients is extremely low. If these cells are easily detectable, cancer diagnosis may be possible by simply using a blood test, thus reducing patient burden. This study aimed to develop a cancer detection device by combining a microfilter that can be dynamically deformed and a nucleic acid aptamer that has a specific binding ability to cancer cells for easy detection. The cancer detection device was fabricated by photolithography, electroforming, and three-dimensional printing. The cancer cell detection ability of the fabricated device was evaluated using 1 mL of blood samples spiked with different concentrations of cancer cells. The lowest concentration of cancer cells in the blood was 5 cancer cells/1 mL blood. The fabricated microfilters specifically detected cancer cells in the blood successfully at exceedingly low concentrations. Moreover, the cancer detection experiment results using human whole blood revealed that cancer detection could be performed with higher accuracy using the fabricated cancer detection device compared to pre-existing cancer detection equipment (e.g., CellSearch system, Veridex). These findings provide important insights into the use of cancer cells in the blood as a diagnostic approach for cancer. [Display omitted] • We developed a cancer detection device using a microfilter and nucleic acid aptamer. • The device was evaluated using 1 mL blood spiked with cancer cells. • The lowest detectable concentration of cancer cells in blood was 5 CTCs/1 mL blood. • The fabricated microfilters specifically detected low concentrations of cancer cells. • This method showed higher accuracy than the CellSearch System. [ABSTRACT FROM AUTHOR]

The superior solution set search problem contains parameters that provide constraints on evaluation value and distance. Therefore, in this article, we propose an evaluation indicator that is inspired by a method based on a dominance relation in multiobjective optimization problems and includes the aforementioned parameters. We also propose a search method based on the genetic algorithm (GA) with this indicator and perform numerical experiments on unique superior solution set search problems. The proposed method finds more superior solutions than the conventional single‐objective optimization method, which confirms its usefulness. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

In this letter, an adaptive Cuckoo Search with a parameter adjustment mechanism of each search point by using parameters of the search points variously and ranking of search points is proposed. The neighborhood area of the search point of the proposed method differs depending on its ranking. The search performance of the proposed method is verified through numerical simulations for typical benchmark problems. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

It is difficult to fabricate three-dimensional structures using semiconductor-process technology, because it is based on two-dimensional layered structure fabrication and the etching of thin films. In this study, we fabricated metal structures that can be dynamically deformed from two-dimensional to three-dimensional shapes by combining patterning using photolithography with electroforming technology. First, a resist structure was formed on a Cu substrate. Then, using a Ni sulfamate electroforming bath, a Ni structure was formed by electroforming the fabricated resist structure. Finally, the resist structure was removed to release the Ni structure fabricated on the substrate, and electroforming was used to Au-plate the entire surface. Scanning-electron microscopy revealed that the structure presented a high aspect ratio (thickness/resist width = 3.5), and metal structures could be fabricated without defects across the entire surface, including a high aspect ratio. The metallic structures had an average film thickness of 12.9 µm with σ = 0.49 µm, hardness of 600 HV, and slit width of 7.9 µm with σ = 0.25 µm. This microfabrication enables the fabrication of metal structures that deform dynamically in response to hydrodynamic forces in liquid and can be applied to fields such as environmental science, agriculture, and medicine.