Masashi Miura

Communication-Based Decentralized Demand Response for Smart Microgrids

Demand response (DR) is one of the most promising solutions to efficient control of smart grids with renewable energy resources. Usually, DR programs are implemented by means of centralized control by power supply companies or independent system operators. In contrast, recently, the focus has been on decentralized control to enhance the efficient use of distributed energy resources especially on microgrids. This paper proposes a decentralized control system for DR. The key of the proposed method is a new decentralized algorithm for determining appropriate control signals (corresponding to prices and/or incentives) by using communication networks provided by smart meters. The effectiveness of the proposed method is illustrated by a numerical example.

Distributed constraint optimization on networked multi-agent systems

This paper deals with a distributed constraint optimization problem on networked multi-agent systems. First, we propose a distributed algorithm based on the Lagrangian method, where a new update law of the Lagrangian multiplier is designed. This update law enables each agent to estimate the value of the Lagrangian multiplier in a distributed manner. Next, we derive a necessary and sufficient condition that the optimization problem is solvable in a distributed manner over a graph. Finally, we apply the proposed method to power grid control via distributed pricing to maintain the supply-demand balance.

A wireless sensor network platform for water quality monitoring

We have developing a wireless sensor network system for water quality monitoring. It consists of various sensors for the sensing of physical and chemical properties of water, and systems including wireless communication module, power module and interface between sensors and wireless communication module. In this paper, we report the development results of a novel wireless sensor network platform for water quality monitoring, which is proposed for rapid prototyping of wireless sensor network system. In order to demonstrate our novel wireless sensor network platform, we fabricated the platform as a sensor node and field-tested it with several sensors in the lake. As a result, we could confirm that our proposed novel platform was operated successfully in real environment.

Complete distributed optimization with constraints on networked multi-agent systems and its application to real-time pricing

This paper deals with a distributed constraint optimization problem on networked multi-agent systems. First, we propose a complete distributed algorithm based on the Lagrangian method which does not rely on supervisors. A new method to estimate the Lagrangian multiplier is proposed which enables each agent to obtain the Lagrangian multiplier in a distributed manner. Next, we derive a necessary and sufficient condition that the optimization problem is solvable in a distributed manner over a given network. Finally, a numerical example illustrates the effectiveness of the proposed method.

Graphical and scalable multi-agent simulator for real-time pricing in electric power grid

AbstractWith growing great interest in the energy problems, real-time pricing (RTP) for power systems has attracted attention in the world. In our research, a new distributed optimization method is proposed for RTP. It is based on negotiations between players (consumers, suppliers and distributors) through information networks. Then we developed a graphical and scalable multi-agent simulator for RTP which is named “RTPsim” for further investigations. RTPsim enables us to conduct numerical simulations in various conditions and various scales. This paper shows the new distributed optimization method based on negotiations, the features of our graphical and scalable RTP simulator and examples of simulation results.

Agent-Based Modeling and Simulation for Two-Dimensional Spatial Competition

We examine a feasibility study on agent-based modeling and simulation for spatial competition originating from Hotelling model. Hotelling model is a theory that explains the consequence of the spatial competition between two shops. This model is employed to explain little product differentiation and agglomeration of retail shops. Conventionally, the researches for spatial competition has employed the analytical approaches in the game situations. On the contrary, our research intends to introduce the agent-based approach. With the agent-based approach, we can deal with discrete and non-uniform consumer distributions which are closer to the actual situation. This paper introduces our agent-based model as extension of two-dimensional Hotelling model and the agent simulator which we’ve developed as a prototype.

Flexible and stackable terahertz metamaterials via silver-nanoparticle inkjet printing

There is presently much interest in tunable, flexible, or reconfigurable metamaterial structures that work in the terahertz frequency range. They can be useful for a range of applications, including spectroscopy, sensing, imaging, and communications. Various methods based on microelectromechanical systems have been used for fabricating terahertz metamaterials, but they typically require high-cost facilities and involve a number of time-consuming and intricate processes. Here, we demonstrate a simple, robust, and cost-effective method for fabricating flexible and stackable multiresonant terahertz metamaterials, using silver nanoparticle inkjet printing. Using this method, we designed and fabricated two arrays of split-ring resonators (SRRs) having different resonant frequencies on separate sheets of paper and then combined the two arrays by stacking. Through terahertz time-domain spectroscopy, we observed resonances at the frequencies expected for the individual SRR arrays as well as at a new frequency due...

Study of a new type of UAV with vertical fins

Use of a rotor type UAV that can perform three-dimensional movement and hover is being actively pursued. Although a multi-rotor type UAV is important, because it is driven by electric motors its application has the limitation of a short cruising time. In this study, the composition and control system of a single rotor UAV that achieves attitude control by pivotable vertical fins are proposed. Herein, the results of the dynamical simulations and experiments using a bread board model of the proposed UAV are described.

A Feasibility Study on the Simultaneous Sensing of Turbidity and Chlorophyll a Concentration Using a Simple Optical Measurement Method

We have been developing a wireless sensor network system to monitor the quality of lake water in real time. It consists of a sensor module and a system module, which includes communication and power modules. We have focused on pH, turbidity and chlorophyll a concentration as the criteria for qualifying lake water quality. These parameters will be detected by a microfluidic device based sensor module embedded in the wireless sensor network system. In order to detect the turbidity and the chlorophyll a concentration simultaneously, we propose a simple optical measurement method using LED and photodiode in this paper. Before integrating a turbidity and chlorophyll a concentration sensor into the microfluidic device based pH sensor, we performed feasibility studies such as confirmation of the working principle and experiments using environmental water samples. As a result, we successfully verified our simultaneous sensing method by using a simple optical setup of the turbidity and the chlorophyll a concentration.

Turbidity monitoring of lake water by transmittance measuresment with a simple optical setup

We are developing a wireless sensor network system for the lake water quality monitoring, which consists of sensor module, wireless transceiver module, control ICs and power module. In the sensor module, sensors to monitor the water quality such as pH sensor, turbidity sensor, chlorophyll concentration sensor and dissolved oxygen concentration sensor, will be integrated as a microfluidic device. The power module of a sensor node of the wireless sensor network system will be implemented with solar cells and thermoelectric effect based energy harvesting devices utilizing temperature difference between the surface and the bottom water layer. In this paper, we report the feasibility study results of a turbidity sensor that will be integrated into the sensor module for the lake water quality monitoring. Our turbidity sensor has been achieved by a simple optical setup, which consists of LED and photodiode. The turbidity is determined by measuring the transmittance of scattered LED light by the particles in the water sample. As a result of experiments with the lake water sample, we could verify that our simple optical measurement setup can be a useful tool in turbidity sensing.