Chiba Institute of Technology

About: Chiba Institute of Technology is a education organization based out in Narashino, Japan. It is known for research contribution in the topics: RNA & Magnet. The organization has 2663 authors who have published 4999 publications receiving 56870 citations. The organization is also known as: Chiba kōgyō daigaku & Kōa Institute of Technology.

A sensor platform for outdoor navigation using gyro-assisted odometry and roundly-swinging 3D laser scanner

Abstract: This paper proposes a light-weight sensor platform that consists of gyro-assisted odometry and a 3D laser scanner for localization of human-scale robots. The gyro-assisted odometry provides highly accurate positioning only by dead-reckoning. The 3D laser scanner has a wide field of view and uniform measuring-point distribution. Robust and computationally inexpensive localization is implemented on the sensor platform using a particle filter on a 2D grid map generated by projecting 3D points on to the ground. The system uses small and low-cost sensors, and can be applied to a variety of mobile robots in human-scale environments. Outdoor navigation experiments were performed at the Tsukuba Challenge 2009, which is an open proving ground for human-scale robots. Our robot successfully navigated the assigned 1-km course in a fully autonomous mode multiple times.

Discovery of extremely REY-rich mud in the western North Pacific Ocean

Abstract: Copyright © 2016 by The Geochemical Society of Japan. ment of green technologies, including electric and hybrid vehicles, compact and long-life LED lights, and wind power generation, is required to shift human society toward sustainable growth. Rare-earth elements and yttrium, hereinafter together called REY, are essential elements for products with these advanced and green technologies, because of the magnetic and optical properties of REY that result from the characteristic configurations of electrons in these elements. With rising economic growth in Discovery of extremely REY-rich mud in the western North Pacific Ocean

AFM-Based Robotic Nano-Hand for Stable Manipulation at Nanoscale

Abstract: One of the major limitations for Atomic Force Microscopy (AFM)-based nanomanipulation is that AFM only has one sharp tip as the end-effector, and can only apply a point force to the nanoobject, which makes it extremely difficult to achieve a stable manipulation. For example, the AFM tip tends to slip-away during nanoparticle manipulation due to its small touch area, and there is no available strategy to manipulate a nanorod in a constant posture with a single tip since the applied point force can make the nanorod rotate more easily. In this paper, a robotic nano-hand method is proposed to solve these problems. The basic idea is using a single tip to mimic the manipulation effect that multi-AFM tip can achieve through the planned high speed sequential tip pushing. The theoretical behavior models of nanoparticle and nanorod are developed, based on which the moving speed and trajectory of the AFM tip are planned artfully to form a nano-hand. In this way, the slip-away problem during nanoparticle manipulation can be get rid of efficiently, and a posture constant manipulation for nanorod can be achieved. The simulation and experimental results demonstrate the effectiveness and advantages of the proposed method.

Phase diagram and collective excitations in an excitonic insulator from an orbital physics viewpoint

Abstract: An excitonic-insulating system is studied from a viewpoint of the orbital physics in strongly correlated electron systems. An effective model Hamiltonian for low-energy electronic states is derived from the two-orbital Hubbard model with a finite-energy difference corresponding to the crystalline-field splitting. The effective model is represented by the spin operators and the pseudospin operators for the spin-state degrees of freedom. The ground-state phase diagram is analyzed by the mean-field approximation. In addition to the low-spin state and high-spin state phases, two kinds of the excitonic-insulating phases emerge as a consequence of the competition between the crystalline-field effect and the Hund coupling. Transitions to the excitonic phases are classified to an Ising-type transition resulted from a spontaneous breaking of the ${Z}_{2}$ symmetry. Magnetic structures in the two excitonic-insulating phases are different from each other: an antiferromagnetic order and a spin nematic order. Collective excitations in each phase are examined using the generalized spin-wave approximation. Characteristics in the Goldstone modes in the excitonic-insulating phases are studied through the calculations of the dynamical correlation functions for the spins and pseudospin operators. Both the transverse and longitudinal spin excitation modes are active in the two excitonic-insulating phases in contrast to the low-spin state and high-spin state phases. Relationships of the present results to the perovskite cobalt oxides are discussed.

Comparison of Microstructure and Oxidation Behavior of CoNiCrAlY Bond Coatings Prepared by Different Thermal Spray Processes

Abstract: To protect various gas turbine components against high temperature in the hot sections of power generation plants and aircraft engines, thermal barrier coatings (TBCs) have been developed and widely used. Conventional TBCs consist of a MCrAlY bond coating for oxidation resistance and a ceramic top coating for thermal insulation. High quality coatings of MCrAlYs have been produced mostly by low pressure plasma spraying but other more economical processes are also used depending on the operating conditions of the component to be coated. In this study, CoNiCrAlY powders were deposited on Inconel 718 substrate with 3 types spraying system, i.e., low pressure plasma spraying, high velocity oxy-fuel spraying, and atmosphere plasma spraying. The specimens without top ceramic coating were isothermally tested for up to 100 hrs in air at 1373 K and mass gain of the coatings was measured. Microstructure of the coating cross sections and the surface oxides were observed with SEM. Moreover, phase changes during the oxidation test were investigated with calculated phase diagrams for the CoNiCrAlY alloy. [doi:10.2320/matertrans.47.1638]