University of Electro-Communications

About: University of Electro-Communications is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Laser & Robot. The organization has 8041 authors who have published 16950 publications receiving 235832 citations. The organization is also known as: UEC & Denki-Tsūshin Daigaku.

Molecular Robots with Sensors and Intelligence

Abstract: ConspectusWhat we can call a molecular robot is a set of molecular devices such as sensors, logic gates, and actuators integrated into a consistent system. The molecular robot is supposed to react autonomously to its environment by receiving molecular signals and making decisions by molecular computation. Building such a system has long been a dream of scientists; however, despite extensive efforts, systems having all three functions (sensing, computation, and actuation) have not been realized yet.This Account introduces an ongoing research project that focuses on the development of molecular robotics funded by MEXT (Ministry of Education, Culture, Sports, Science and Technology, Japan). This 5 year project started in July 2012 and is titled “Development of Molecular Robots Equipped with Sensors and Intelligence”.The major issues in the field of molecular robotics all correspond to a feedback (i.e., plan–do–see) cycle of a robotic system. More specifically, these issues are (1) developing molecular sensor...

Holographic manipulation of nanoparticle distribution morphology in nanoparticle-dispersed photopolymers

Abstract: We report on experimental verification of mass transfer of nanoparticles during holographic recording in nanoparticle-dispersed photopolymers. Through direct observations of the microscopic structure of recorded holograms as well as optical measurements of the phase shift between the light interference pattern and a recorded hologram we find that holographic exposure causes nanoparticles to be redistributed from bright to dark regions, leading to periodic assembly of nanoparticles and thereby to formation of high-contrast holograms.

Anisotropy in conductance of a quasi-one-dimensional metallic surface state measured by a square micro-four-point probe method.

Abstract: We have devised a "square micro-four-point probe method" using an independently driven ultrahigh-vacuum four-tip scanning tunneling microscope, and succeeded for the first time to directly measure anisotropic electrical conductance of a single-atomic layer on a solid surface. A quasi-one-dimensional metal of a single-domain Si(111)4 x 1-In had a surface-state conductance along the metallic atom chains (sigma(axially)) to be 7.2(+/-0.6) x 10(-4) S/square at room temperature, which was larger than that in the perpendicular direction (sigma(radially)) by approximately 60 times. The sigma(axially) was consistently interpreted by a Boltzmann equation with the anisotropic surface-state band dispersion, while the sigma(radially) was dominated by a surface-space-charge-layer conductance.

High-cycle rotating bending fatigue property in very long-life regime of high-strength steels

Abstract: In order to investigate the fatigue properties of high-strength steels in the very long-life regime up to over 10 9 cycles, cantilever-type rotating bending fatigue tests were carried out for two kinds of high-strength steels, SUJ2 and SNCM439, which were machined by grinding and finished by electropolishing after grinding. And also, the residual stress on the specimen surface of the ground specimen was examined by X-ray diffractometer in order to investigate effects of the residual stress on the fatigue properties. From the investigations, the S-N curves clearly have a tendency to decrease again in the longer-life range over 10 7 cycles for both types of specimen and for both steels. From observations of fracture surfaces, it was found that fatigue crack origins could be grouped into two types: (i) 'surface crack origin type' in the shorter-life regime and (ii) 'internal crack origin type' in the longer-life regime.

Fragmentation Problems and Management Approaches in Elastic Optical Networks: A Survey

Abstract: Bandwidth fragmentation, a serious issue in elastic optical networks (EONs), can be suppressed by proper management in order to enhance the accommodated traffic demands. In this context, we need an in-depth survey that covers bandwidth fragmentation problems and how to suppress them. This survey paper starts with the basic concept of EONs and their unique properties. This paper then moves to the fragmentation problem in EONs. We discuss and analyze the major conventional spectrum allocation policies in terms of the fragmentation effect in a network. The taxonomies of the fragmentation management approaches are presented along with different node architectures. Subsequently, this paper reviews state-of-the-art fragmentation management approaches. Next, we evaluate and analyze the major fragmentation management approaches in terms of blocking probability. Finally, we address the research challenges and open issues on fragmentation problem in EONs that should be addressed in future research.