This paper presents a method of wireless-power transmission to devices which move from close distance to far area from transmitting antenna. UHF range, specifically 430 MHz, was selected in this study so that both of the near-field and the electro-magnetic energy would exist in the applicable distance and the rectenna would be small enough. The resulting hardware is compact and light enough to be installed on a moving target with only minor sacrifices in size and weight. As a demonstration of this concept, a rectenna and two driving motors were embedded in each of the four rotors of a quadcopter. The rotor assembly (rotor, antenna, rectifier, two motors) is powered by UHF waves and rotates around a mechanically fixed shaft. Successful test flights of the quadcopter demonstrate the feasibility of wireless power transmission to mobile targets.
This paper describes a noise reduction method for acoustic distance measurement using cross spectrum between 2ch observations, constructing analytic signal based on cosine and sine linear chirp sound. Specifically, synchronous addition is applied to observed signals themselves or to their cross spectrum.
In this paper, we propose a data relaying method for heterogeneous networks using device to device (D2D) communications. The proposed method uses two communication types (D2D communications and cellular communications) to reduce power consumption of terminals. At first, a source node in a macro cell transmits a data to a relay node in a small cell with D2D communications. Second, the relay node in a small cell transmits the data to a base station (BS) with cellular communications. We implement the proposed method on MATLAB, and confirm that the proposed method can reduce power consumption of terminals in heterogeneous networks. From the computer simulations, the proposed method can achieve 33 percent less power consumption compared with the existing method.
Recently, the system for massed tag management (at 13.56 MHz) and the system for the long distance identification (at 920 MHz) have been carried out to practical use. For continuous logistics, it is desired that those be integrated seamlessly. However, integration into the system, which uses the frequency band of 13.56 MHz, is disadvantageous to keep the feature of the long distance identification. In this paper, the system that identifies nearby cluttered tags by the frequency band for the long distance identification is described.
Smart metering systems with Wireless Smart Utility Network (Wi-SUN) have been introducing in gas and water infrastructures for optimal management of energy and resources. These wireless systems require low-power consumption to operate long period, e.g., 10 years by battery operation. One of the solutions is development of Media Access Control (MAC) protocol for low-power operation. The Feathery Receiver Initiated Transmission (F-RIT) protocol is one of the implementable low-power consumption MAC protocol complied with IEEE 802.15.4g global standard for the MAC layer of the Wi-SUN systems. In this paper, the feasibility and effectiveness of the F-RIT protocol are experimentally investigated in terms of communication link establishment success rate performance and power consumption performance by implementing the F-RIT protocol on commercial Wi-SUN modules equipped with IEEE 802.15.4g complied RF module.
Pictures of four kinds of filled shapes (circle, equilateral triangle, square and regular pentagon) colored by red, green, blue and corresponding grays were prepared. As a typical brain-computer interface (BCI) paradigm using P300, pictures were presented in an oddball paradigm. Target stimulus was selected from four filled shapes of specific color and non-target stimuli were the other filled shapes of the same color. Twelve experiments (twice for each color) were implemented. Subjects counted whenever targets were detected. For each color, the P300 peak amplitude for target minus that for non-target which relate to signal-to noise ratio (S/N) were calculated. S/N for red and blue were larger than those for the corresponding grays. Correct rates of BCI calculated by the statistical method for red, green and blue were higher than those for the corresponding grays. Peak latency for red was shorter than that for the corresponding gray. These results showed the probability of improvement of noise proof property, correct rate and rapidity of BCI by using effects of colors.
This paper proposes dependable parallel differential evolutionary particle swarm optimization (DEEPSO) for on-line optimal operational planning of energy plants. The planning can be formulated as a mixed integer nonlinear optimization problem (MINLP). When optimal operational planning of numbers of energy plants are calculated simultaneously in a data center, it is required to generate optimal operational planning as rapidly as possible considering control intervals and numbers of treated plants. One of the solutions for this challenge is speed-up by parallel and distributed processing (PDP). However, PDP utilizes numbers of processes and countermeasures for various faults of the processes should be considered. On-line optimal operational planning requires successive calculation at every control interval for keeping customer services. Therefore, sustainable (dependable) calculation keeping quality of solutions are required even if some of the calculation results cannot be returned from distributed processes. Using the proposed dependable parallel DEEPSO based method, calculation time becomes about 3 times faster than that by a sequential calculation, and high quality of solutions can be kept even with high fault probabilities.
The built-in inspection is very important for quality control in precision cutting by throw-away tip. We propose a new automatic inspection method for tool ware of industrial devices. We first do contrast enhancement of the ware image and then segment the cutting ware region by using Otsu thresholding method from the enhanced image. The area of the cutting ware region is used a measure of cutting ware degree. Experimental results show that the proposed method is effective for automatic inspection of throw-away tips in precision cutting.
The goal of this research is to understand the true distribution of character patterns. Advances in computer technology for mass storage and digital processing have paved way to process a massive dataset for various pattern recognition problems. If we can represent and analyze the distribution of a large-scale pattern set directly and understand its relationships deeply, it should be helpful for improving classifier for pattern recognition. For this purpose, we use a visualization method to represent the distribution of patterns using a relative neighborhood graph (RNG), where each node corresponds to a single pattern. Specifically, we visualize the pattern distribution using a compressed representation of RNG (Clustered-RNG). Clustered-RNG can visualize inter-class relationships (e.g. neighboring relationships and overlaps of pattern distribution among “multiple classes”) and it represents the distribution of the patterns without any assumption, approximation or loss. Through large-scale printed and handwritten digit pattern experiments, we show the properties and validity of the visualization using Clustered-RNG.
This paper proposes a single-frame super-resolution algorithm based on the dictionary learning technique without sample image set. Because example-based super-resolution techniques often demand the sample image set to construct the dictionaries, the performance of these techniques depend heavily on the sample image set.
In this paper, utilizing the image segmentation technique, we propose to construct the dictionaries without using sample set. Experiment results show the effectiveness of the proposed algorithm.
Data replication method reducing data restoration time is evaluated on backup server fault model assuming Great East Japan Earthquake. Use-case is to back up important data via network in preparation to large-scale disasters. When the number of backup servers increases, restoration time becomes short because of parallel restoration; therefore, the restored data can be accessed as soon as possible. However, the amount of backup data also increases. In this study, data replication methods are classified, and evaluation functions are created for each method. Restoration time is calculated by using the backup server fault model, and then balanced method is revealed.
In order to solve our energy and environmental issues, it is important not only to make efforts by industrial fields but also to promote pro-environmental behaviors (PEBs) in our daily lives. It is however difficult for us to keep doing PEBs for a long time. In order to keep it, it can be effective that they join an online community because they can interact with each other to keep their motivations in the community even if they live in distant places. In this study, the authors have proposed an online community operation model to promote our PEBs. The model is organized based on six principles of compliance-gaining strategies and aims to promote not only their message postings to Bulletin Board System (BBS) but also their PEBs. An online community which realized the model was built and had been operated as a case study for four weeks where 10 participants had joined. As the result, it was found that their message posting activities had been kept to the end and PEBs activities of half of them were significantly improved.
In the paper, we propose a method of utilizing smart device in measure lesson of proficiency test aimed at active learning. The purpose of this method is to aim essential interactive lesson and the students’ autonomy study outside of class. In addition, the aim of the proposed method is the improvement of learning effect. In order to realize of these aims, the proposed method in view of the problems of the previous methods is based on the Bluetooth and SQLite of smart devices without internal and external supports and constructed by based on the ADDIE model. Through the implementation of the actual measure lesson, evaluation of the proposed method to the improvement of the learning effect is analyzed by the listening score results of Korean proficiency test.
In this letter, a new type of tunable hybrid circuit is introduced. First, a circuit theory of proposed hybrid circuit is reported. The proposed hybrid circuit is constructed by a general branch-line type hybrid circuit and four matching networks using tunable capacitance elements. Next, S parameter characteristics of the hybrid circuit are presented, and effectiveness of the circuit theory is confirmed.