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MODULATION OF GRAPHENE FIELD EFFECT TRANSISTOR CHARACTERISTICS BY TUNING ACIDITY OF SiO_2 SUBSTRATE
Get PDFSince the chemical environment such as the interface with the substrate and the surface adsorption species has a large influence on the electronic characteristics of graphene, it is necessary to study to control the interface interactions with guest chemical species to modulate the electronic state of graphene. In this study, the surface of the SiO_2 / Si substrate supporting graphene in a field-effect transistor (FET) was chemically modified with self-assembled monolayers (SAMs) with different acidity to tune the gate voltage V_G dependence of the electrical conductivity (transfer curve) upon molecular adsorption. The charge neutral points of FETs changed upon acidity of SAMs on substrate, explained by the electrochemical doping mechanism
REMOVAL OF BORIC ACID ION AND MERCURY ION IN WASTEWATER USING LAYERED DOUBLE HYDROXIDES
Get PDFWe have attempted to synthesize layered double hydroxides (LDHs) adsorbents that can selectively remove harmful substances such as boron (B) and mercury (Hg) contained in wastewater. The calcined CaAl-LDH demonstrated high B removal performance of 96% in the B solution coexisting with sulfate ions. The calcined CaAl-LDH forms ettringite and incorporates B into the crystals, achieving a level of purification below the effluent standards. Furthermore, [S_3]^2- intercalated MgAl-LDH can selectively remove Hg from Hg-contaminated water containing Mn and Fe ions
PROPOSAL FOR A SOFT CLIMBING ROBOT WITH UPWARD DRINING FORCE BY PROPELLER
Get PDFIn recent years, many bio-inspired robots have been developed, and especially octopus-like robots that can grasp various objects and climb various columnar objects have attracted considerable attention. In addition, application for inspection of huge infrastructures is expected. In this research, we improve the mobility of our previous soft climbing robot by adding a propeller-driven climbing mechanism
Novel design methods of central nervous system of C. elegans and olfactory bulb model of mammal based on sequential logic and numerical integration
Get PDFThis study proposes a novel design method of a neuromorphic electronic circuit: design of a neuromorphic circuit based on appropriately selected hybrid dynamics of synchronous sequential logic, asynchronous sequential logic, and numerical integration. Based on the proposed design method, a novel central nervous system model of C. elegans, and an olfactory bulb model are presented. It is then shown that the presented models can realize typical responses of a conventional central nervous system model of C. elegans, and the observation of chaos in the olfactory bulb. Furthermore, the presented models are implemented by a field programmable gate array and the presented model of C.elegans is used to control a prototype robot of C. elegans body. Then, experiments validate that the presented central nervous system model enables the body robot to reproduce typical chemotaxis behaviors of the conventional C. elegans model. In addition, comparisons show that the presented model consumes fewer circuit elements and lower power compared to various central nervous system models of C. elegans based on synchronous sequential logic, asynchronous sequential logic, and numerical integration
ANALYSIS OF PERIODIC ORBITS IN COUPLED DIGITAL RETURN MAPS
Get PDFThis paper considers periodic orbits in coupled digital spike maps. The digital spike map is a digital dynamical system defined by a set of points. The digital spike map can generate a variety of periodic orbits. Digital dynamical systems are suitable for precise numerical analysis, hardware implementation using FPGA and can be applied to various systems including neural networks. We can obtain the coupled digital spike map by mutual coupling of two digital spike maps. The coupled system can exhibit a variety of periodic orbits. First, we introduce typical examples generated by coupled digital spike maps. Next, we introduce two simple feature quantities for quantitative analysis of the behavior of periodic orbits. The first quantity evaluates complexity of periodic orbits. The second quantity evaluates stability of periodic orbits. We construct feature planes using two feature quantities for analysis. We focus on maximum periodic orbits because the phenomena are complex
Analysis of dynamic binary neural networks based on evolutionary computation
Get PDFWe consider evolutionary synthesis of permutation binary neural network characterized by global permutation connection and local binary connection. The network is simple version of dynamic binary neural network. Although the networks are simple and the parameter space is small, the networks exhibit various periodic orbits of binary vectors. Since analysis of all the periodic orbits is not easy, we focus on globally stable periodic orbits such that almost all initial points fall into the orbits. We present a simple search algorithm for globally stable periodic orbits. Applying the algorithm, we have clarified that permutation binary neural networks generate a variety of globally stable periodic orbits
STUDY ON LUMINESCENCE STABILITY OF COLLOIDAL SI NANOCRYSTALS PREPARED FROM POROUS SILICON
Get PDFSi crystal particles with a diameter of several nanometers exhibits visible light emission at room temperature due to the quantum size effect. Since Silicon exists abundantly in the earth\u27s crust, it is inexpensive and is expected to be applied to future light-emitting materials as an environmentally friendly material. The purpose of this research is to improve the luminescence stability by changing the experimental conditions for preparing colloidal silicon nanocrystals from porous silicon
A STUDY OF DESIGN OPTIMIZATION SYNCHRONOUNS RELUCTANCE MOTORS USING ELECTOROMAGNETICS-MECHANICS COUPLED TOPOLOGY OPTIMIZATION METHOD
Get PDFRecentry, demand for higher efficiency of motor has increased due to global warming, the electrification of cars and others. the synchronous reluctance motors are inexpensive because they do not require magnets, the torque characteristic is lower than that of the interior permanent magnet motor. Furthermore, when the motor rotates on the high speed, it is necessary to enhance not only the high efficiency but also the high stiffness. When designing motors with high efficiency and high stiffness, "electromagnetics-mechanics coupled topology optimization" is useful to automatically estimate the machine geometry that satisfies the design goals. This paper investigates a electromagnetics-mechanics coupled topology optimization method for synchronous motors, which using density-level set method and structural mutation to prevent grayscale residuals and convergence to local minimum
Recommendation Algorithms Based on Behavioral History.
Get PDFWith the rapid popularity of Internet and mobile Internet, the number of movie entertainment information on the Web is quite huge, and it is increasingly difficult for people to obtain information about movies of interest. In this study, we propose a personalized recommendation strategy based on the sequence of user playing behavior for the personalized recommendation problem of movie websites. The strategy analyzes the user playing video behavior data by Word2vec, a deep neural network word vector model, maps the videos into equal-dimensional feature vectors, calculates the similarity of movies, and uses it as the basis of recommendation to generate a recommendation list to users. In addition, to improve recommendation accuracy, Word2vec parameter settings were considered, and a pre-processing method for history sequences was proposed
MEASUREMENT OF INTERFERENCE WAVE IN ELECTRIC FIELD COMMUNICATION ON LARGE METAL PLATE
Get PDFWe study electric field communication on a large metal plate．Since electric field communication can use metal as a transmission line, it is expected to be applied to things made of metal such as cars and robots.．Interference noises from environmental electronic equipment propagate along the large metal plate and disturb the communication. Therefore, the influence of the interference noise on communication performance should be examined. This paper reports on the interference measurement in electric field communication on a large metal plate with an electrically isolated measuring instrument