1,167 research outputs found
Single-Motor Robotic Gripper With Three Functional Modes for Grasping in Confined Spaces
This study proposes a novel robotic gripper driven by a single motor. The
main task is to pick up objects in confined spaces. For this purpose, the
developed gripper has three operating modes: grasping, finger-bending, and
pull-in modes. Using these three modes, the developed gripper can rotate and
translate a grasped object, i.e., can perform in-hand manipulation. This
in-hand manipulation is effective for grasping in extremely confined spaces,
such as the inside of a box in a shelf, to avoid interference between the
grasped object and obstacles. To achieve the three modes using a single motor,
the developed gripper is equipped with two novel self-motion switching
mechanisms. These mechanisms switch their motions automatically when the motion
being generated is prevented. An analysis of the mechanism and control
methodology used to achieve the desired behavior are presented. Furthermore,
the validity of the analysis and methodology are experimentally demonstrated.
The gripper performance is also evaluated through the grasping tests
Measurements of stratospheric ozone by rocket ozonesondes in Japan
A small optical ozone instrument has been developed for a rocket-borne dropsonde to measure the altitude profile of stratospheric ozone. It consists of a four-color filter photometer that measures the attenuation of sunlight as a function of altitude at four wavelengths in the middle ultraviolet. The ozone dropsonde is launched aboard a meteorological rocket MT-135, providing the altitude profiles of ozone as well as atmospheric temperature and wind. The rocket launchings have been carried out five times since August 1990 at Uchinoura (31 deg N, 131 deg E), Japan to measure ozone concentration from 52 to 20 km altitudes during the slow fall of the dropsonde. The ozone profiles measured in summer (August 27, 1990; Sep. 11 and 12, 1991) were very stable above an altitude of 28km. where as those measured in winter (Feb. 9, and 11, 1991) showed considerable day-to-day variations at the stratospheric altitudes. Ozone, temperature and wind profiles measured simultaneously by both rocket and balloon ozonsondes are compared with CIRA 1986 model atmosphere
An approach to nutritional therapy of hepatic encephalopathy by normalization of deranged amino acid patterns in serum
A mixture with essential and nonessential amino acids
high in branched chain amino acids and low in aromatic amino acids (Fischer solution), and another synthetic mixture of branched chain amino acids containing 3 amino acids associated with the urea cycle (Hep-OU) were infused to control subjects and patients with severe hepatic disease. Alterations in serum aminograms, blood ammonia
levels and electroencephalograms following the infusion were studied and compared with those obtained by a commercially available amino acid mixture. Short-term or continuous infusion of a commercially available amino acid solution to cirrhotic patients caused an increase in
methionine, phenylalanine and tyrosine and a decrease in branched chain amino acids. These post-infusion results were similar to the patterns seen in hepatic encephalopathy. In cirrhotic patients, infusion of
Fischer solution which contains small quantities of methionine and phenylalanine produced an increase in the concentrations of these 2 amino acids, probably because of impaired utilization by the injured liver. No marked alterations in serum aminograms, however, were
observed in cirrhotic patients either immediately after, or 3 h after, the end of the Hep-OU infusion. Reduction of methionine, tyrosine and phenylalanine levels and elevation of the molar ratio of (valine+leucine+isoleucine) / (phenylalanine+tyrosine) were significant. The infusion of Hep-OU to patients with liver cirrhosis or subacute hepatitis resulted in clinical and neurological improvements and the restoration of the
molar ratio of branched chain amino acids/aromatic amino acids.</p
3-D Kinematics of Water Masers in the W51A Region
We report proper motion measurements of water masers in the massive-star
forming region W51A and the analyses of the 3-D kinematics of the masers in
three maser clusters of W51A (W51 North, Main, and South). In W~51 North, we
found a clear expanding flow that has an expansion velocity of ~70 km/s and
indicates deceleration. The originating point of the flow coincides within 0.1
as with a silicon-monoxide maser source near the HII region W~51d. In W51 Main,
no systematic motion was found in the whole velocity range (158 km/s =< V(lsr)
=< -58 km/s) although a stream motion was reported previously in a limited
range of the Doppler velocity (54 km/s =< V(lsr) =< 68 kms). Multiple driving
sources of outflows are thought to explain the kinematics of W51 Main. In W51
South, an expansion motion like a bipolar flow was marginally visible. Analyses
based on diagonalization of the variance-covariance matrix of maser velocity
vectors demonstrate that the maser kinematics in W51 North and Main are
significantly tri-axially asymmetric. We estimated a distance to W51 North to
be 6.1 +/- 1.3 kpc on the basis of the model fitting method adopting a radially
expanding flow.Comment: 20 pages, 8 figures, 8 tables, appear in the NRO report No. 564
(ftp://ftp.nro.nao.ac.jp/nroreport/PASJ-W51.pdf) and will appear in Publ.
Astron. Soc. Japan, Vol. 54, No. 5 (10/25 issue
Determining the Optical Geometry of a Gold Semi-Shell under the Kretschmann Configuration
Dielectric nanoparticles coated with metals (half-shell or semi-shell structures) have attracted attention as potential composite plasmonic nanomaterials with large optical anisotropy and absorption cross-sections. Structures approximately 100 nm in size can excite plasmons in the visible and near-infrared ranges, highlighting their distinct optical properties. This study employed metal semi-shell structures (metal: gold, dielectric: silica) in the Kretschmann configuration to experimentally and numerically demonstrate the optical determination of single-structure orientations through a finite-difference time-domain method. Gold semi-shell structures were fabricated through deposition and etching. These structures were removed from their substrate in ultrapure water and randomly dropped onto a thin gold substrate. In the single structure, we experimentally observed changes in the scattering light spectrum based on the optical geometry of the gold semi-shell at wavelengths ranging from 530 to 700 nm. The obtained results closely resembled those of a simulation and confirmed the presence of eigenmodes in the orientation through electric field analysis. These observations allow for the cost-effective and rapid determination of the orientations of numerous structures that are approximately 100 nm in size, solely through optical methods. This technique is a valuable development for measurement applications in nanostructure orientation control and functionality enhancement
- …