A Passivity-Based Distributed Reference Governor for Constrained Robotic Networks

This paper focuses on a passivity-based distributed reference governor (RG) applied to a pre-stabilized mobile robotic network. The novelty of this paper lies in the method used to solve the RG problem, where a passivity-based distributed optimization scheme is proposed. In particular, the gradient descent method minimizes the global objective function while the dual ascent method maximizes the Hamiltonian. To make the agents converge to the agreed optimal solution, a proportional-integral consensus estimator is used. This paper proves the convergence of the state estimates of the RG to the optimal solution through passivity arguments, considering the physical system static. Then, the effectiveness of the scheme considering the dynamics of the physical system is demonstrated through simulations and experiments.Comment: 8 pages, International Federation of Automatic Conference 2017, 8 figure

『易緯』の総合的研究

内容の要約広島大学(Hiroshima University)博士(文学)Doctor of Philosophydoctora

Influence of Substrate Surface Roughness on Synthesized Diamond Films by Flame Combustion on Ti Substrate for Dental Implants

The flame combustion method enables the synthesis of diamonds via acetylene-oxygen gas flame combustion in ambient air, and this method has various advantages over other methods. However, most diamond films synthesized by this method delaminate because of thermal stress during cooling. Titanium (Ti) has recently been utilized as a dental implant in the dental industry. In this study, to improve the strength, wear resistance, and biocompatibility of dental implant surfaces, diamond films were synthesized on a Ti substrate, a dental implant material, by the flame combustion method. Moreover, to obtain high-quality diamond films and achieve good adhesion on the Ti substrate, as a pretreatment of the substrate to prevent delamination, scratch processing, in which a substrate is ground with emery paper in one direction, was performed to roughen the surface. The surface roughness of the Ti substrates was varied by scratching with emery paper of #180, #400, and #1500 grain sizes. According to these results, diamond films were synthesized on the Ti substrate surface by flame combustion. The surface morphology of the synthesized films could be altered by varying the scratching process using emery paper. Delamination of the synthesized films during the scratching process with emery paper #180 (Case A) and #400 (Case B) grain size was completely prevented. However, delamination occurred during the scratching process with a grain size of emery paper #1500 (Case C). To investigate the reason for this result, the surface roughness of the pretreated Ti substrate was observed, and it affected the surface roughness of pretreated Ti substrate affected the surface morphology and delamination of the synthesized diamond films

Endoscopic Laser Treatment for Pediatric Nasal Allergy

We have used the carbon dioxide (CO2) laser and the gallium aluminium arsenide (GaAlAs) diode laser with flexible fiber delivery instruments for vaporization of the inferior nasal turbinate in pediatric patients since 1993. Under endoscopic control, the whole inferior turbinate was vaporized by 5–10 W laser output delivered via an optical fiber. Generally, the nasal mucosa changes into normal mucosa, and symptoms improve. The greatest symptomatic improvement was in nasal obstruction. The results obtained by the two laser devices were similar although they have had different characteristics. Endoscopic laser surgery is effective in the treatment of pediatric nasal allergy

The Subaru Deep Field Project: Lymanα\alpha Emitters at Redshift of 6.6

We present new results of a deep optical imaging survey using a narrowband filter ($NB921$) centered at $\lambda =$ 9196 \AA ~ together with $B$, $V$, $R$, $i^\prime$, and $z^\prime$ broadband filters in the sky area of the Subaru Deep Field which has been promoted as one of legacy programs of the 8.2m Subaru Telescope. We obtained a photometric sample of 58 Ly$\alpha$ emitter candidates at $z \approx$ 6.5 -- 6.6 among $\sim 180$ strong $NB921$-excess ($z^\prime - NB921 > 1.0$) objects together with a color criterion of $i^\prime - z^\prime > 1.3$. We then obtained optical spectra of 20 objects in our $NB921$-excess sample and identified at least nine Ly$\alpha$ emitters at $z \sim 6.5$ -- 6.6 including the two emitters reported by Kodaira et al. (2003). Since our Ly$\alpha$ emitter candidates are free from strong amplification of gravitational lensing, we are able to discuss their observational properties from a statistical point of view. Based on these new results, we obtain a lower limit of the star formation rate density of $\rho_{\rm SFR} \simeq 5.5 \times 10^{-4}$ $h_{0.7}$ $M_\odot$ yr$^{-1}$ Mpc$^{-3}$ at $z \approx 6.6$, being consistent with our previous estimate. We discuss the nature of star-formation activity in galaxies beyond $z=6$.Comment: 49 pages, 16 figures, PASJ, Vol. 57, No. 1, in pres