Inoue M.,Kitakyushu National College of Technology
Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C | Year: 2013
This paper describes the particle damper design, based on the analytical single mass damper model and experiments with smaller size steel balls. The effects of various system parameters - including mass ratio, particle size, cavity dimensions, intensity, and frequency of excitation - were investigated using a SDOF structure under harmonic force excitation when the vertical excitation is applied to the structure. The damper designs call for that the damped motions of the structure equipped with steel ball particle dampers become periodic as well as kept approximately equivalent as predictions by the analytical model. It is shown that the suitable size of steel ball and container dimensions were found to be selected for the combinations of mass ratio and excitation levels in the vicinity of the optimum range of system. Thus, the particle dampers with steel balls, with moderate mass ratios, can be very effective in attenuating the response of lightly damped structures. © 2013 The Japan Society of Mechanical Engineers.
Kaido C.,Kitakyushu National College of Technology
IEEJ Transactions on Industry Applications | Year: 2013
This paper discusses the increase in thrust with grain-oriented electrical steel sheets (GO) in plunger-type electromagnetic actuators. In these actuators, GO-laminated cores generate reluctance thrusts due to magnetic anisotropy energies in addition to conventional reluctances which are induced by the form anisotropies of the cores. Therefore, the maximum thrusts, which are induced at a displacement of about the core tooth width, increase by using GO-laminated core. The thrusts of GO cores are approximately 10% larger with high exciting current than those of non-oriented electrical steel sheet cores, and consequently may reduce copper losses by about 40% and iron losses by about 60%. © 2013 The Institute of Electrical Engineers of Japan.
Nagamura T.,Kitakyushu National College of Technology
Kobunshi | Year: 2015
Recent advances on polymeric and organic materials are reviewed from viewpoints of photoresponses and change or control of optical properties by various stimuli. The former includes photonic upconversion with noncoherent light based on tripet-triplet annihilation, ultrafast photoinduced electrochromism for all-optical signal processing in the optical telecommunication wavelength region, real-time holographic display by fast photochromism and photorefractive effects, optical polarization switching in chiral photomagnet, photoinduced changes in macroscopic shapes for future photo-driven motors, and photochemically reversible liquefaction and solidification. The latter includes a thermochromic coordination polymer with high thermal stabililty for temperature sensitive paints, high-performance electro-optic polymer modulators superior to conventional inorganic crystals, various chemical-and bio-sensing properties based on amplified fluorescence quenching or color changes in polymeric photonic crystals, mechanochromism due to stress-induced ring-opening, polymer chain dissociation, or changes in aggregation. Highly ordered photonic crystal films of block copolymers recently commercialized as notch filters for Raman spectroscopy are also shown. Efforts to fully utilize many useful properties of light are further expected. © 2015 The Society of Polymer Science. Japan.
Matsuo T.,Kitakyushu National College of Technology |
Ishii K.,Kyushu Institute of Technology
Proceedings of the SICE Annual Conference | Year: 2012
Robot are expect to be new tools for the operations and observations in the extreme environments where human has difficulties for accessing directly, deep ocean, space, nuclear plants and so on. One of the important matters to realize mobile robots for extreme environments are to establish systems in the movement and their structures which are strong enough to disturbance. A solution for realization an adaptive control system is to learn and imitate biological systems. For example, in the spinal cord of animals, neural oscillator systems called Central Pattern Generator (CPG) are proven to exist and investigated that CPG control rhythmical signals such as swimming pattern, walking locomotion, heart beats, etc. In this paper, an adaptive control system based on the feature of neural oscillators was developed and applied to motion control of a snake-like robot. © 2012 SICE.
Kaushal D.R.,Indian Institute of Technology Delhi |
Kumar A.,YMCA UST |
Tomita Y.,Kyushu Institute of Technology |
Kuchii S.,Kitakyushu National College of Technology |
Tsukamoto H.,Kitakyushu National College of Technology
International Journal of Multiphase Flow | Year: 2013
Pipeline slurry flow of mono-dispersed particles through horizontal bend is numerically simulated by implementing Eulerian two-phase model in FLUENT software. A hexagonal shape and Cooper type non-uniform three-dimensional grid is chosen to discretize the entire computational domain, and a control volume finite difference method is used to solve the governing equations. The modeling results are compared with the experimental data collected in 53.0. mm diameter horizontal bend with radius of 148.4. mm for concentration profiles and pressure drops. Experiments are performed on narrow-sized silica sand with mean diameter of 450 μm and for flow velocity up to 3.56. m/s (namely, 1.78, 2.67 and 3.56. m/s) and four efflux concentrations up to 16.28% (namely, 0%, 3.94%, 8.82% and 16.28%) by volume for each velocity. Eulerian model gives fairly accurate predictions for both the pressure drop and concentration profiles at all efflux concentrations and flow velocities. © 2013 Elsevier Ltd.