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61.
Uniformly layered mixture of the succeeding members in the structure series was found in artificially layered Bi2Sr2Ca
n–1Cu
n
O2n+4 films synthesized by a three-target sequential sputter deposition technique. The intergrowth structure was quantitatively evaluated by X-ray analysis technique. An averagedc-axis (half) unit length and a plane spacing d0-0.31 nm
in the intergrowth structure are considered as a modulation wavelength and an average lattice of superlattice in the analysis. It is shown that the X-ray diffraction patterns observed in our films are in good agreement with that predicted by the superlattice model. 相似文献
62.
Watabe H Hatazawa J Ishiwata K Ido T Itoh M Iwata R Takahashi T Hatano K Nakamura T 《IEEE transactions on medical imaging》1995,14(4):688-696
We proposed a new method (;linearized method') to analyze neuroleptic ligand-receptor specific binding in a human brain using positron emission tomography (PET). We derived the linear equation to solve four rate constants, k(3), k(4), k(5), k(6) from PET data. This method does not demand a radioactivity curve in plasma as an input function to the brain, and can perform fast calculations in order to determine rate constants. We also tested the nonlinearized method including nonlinear equations which is a conventional analysis using plasma radioactivity corrected for ligand metabolites as an input function. We applied these methods to evaluate dopamine D(2) receptor specific binding of [(11)C] YM-09151-2. The value of B(max)/K(d)=k(3)/k (4) obtained by the linearized method was 5.72+/-3.1 which was consistent with the value of 5.78+/-3.4 obtained by the nonlinearized method. 相似文献
63.
A simple and effective technique for synchronizing two independent Ti: sapphire lasers was developed and used for difference-frequency generation. By control of pump intensity, buildup times of these lasers were adjusted to coincide for any combination of wavelengths that was needed for the production of a desired difference frequency. Synchronized pulses were mixed at a AgGaS(2) crystal, producing infrared pulses from 6.2 to 9.7 μm. Characteristic features of the method as well as its possible extension of the tuning range are discussed. 相似文献
64.
S Nakamura S Shibata K Shirota K Abe K Uetsuka H Nakayama N Goto K Doi 《Canadian Metallurgical Quarterly》1996,33(6):696-699
Renal glomerular fibrosis was observed in a 1-year-old spayed female Japanese domestic cat that showed clinically advanced renal failure. In the glomeruli, increased homogeneous materials were stained strongly with aniline blue by Masson's trichrome and positive for anti-type III collagen antibody by immunohistochemical staining, causing mesangial sclerosis and capillary collapse. By electron microscopy, randomly arranged fibrils were observed in the expanded subendothelial and mesangial areas, and the fibrils showed periodicity characteristic of collagen fibers in longitudinal sections. These findings of glomerular lesions closely resemble those of human "collagenofibrotic glomerulonephropathy," which has recently been described as a new type of glomerulonephropathy. 相似文献
65.
66.
Database of human motion has been widely used for recognizing human motion and synthesizing humanoid motions. In this paper,
we propose a data structure for storing and extracting human motion data and demonstrate that the database can be applied
to the recognition and motion synthesis problems in robotics. We develop an efficient method for building a human motion database
from a collection of continuous, multi-dimensional motion clips. The database consists of a binary tree representing the hierarchical
clustering of the states observed in the motion clips, as well as node transition graphs representing the possible transitions
among the nodes in the binary tree. Using databases constructed from real human motion data, we demonstrate that the proposed
data structure can be used for human motion recognition, state estimation and prediction, and robot motion planning. 相似文献
67.
Morihiro Nakamura Yuki Koyama Daisuke Sakamoto Takeo Igarashi 《Computer Graphics Forum》2016,35(7):323-332
We present an interactive design system for designing free‐formed bamboo‐copters, where novices can easily design free‐formed, even asymmetric bamboo‐copters that successfully fly. The designed bamboo‐copters can be fabricated using digital fabrication equipment, such as a laser cutter. Our system provides two useful functions for facilitating this design activity. First, it visualizes a simulated flight trajectory of the current bamboo‐copter design, which is updated in real time during the user's editing. Second, it provides an optimization function that automatically tweaks the current bamboo‐copter design such that the spin quality—how stably it spins—and the flight quality—how high and long it flies—are enhanced. To enable these functions, we present non‐trivial extensions over existing techniques for designing free‐formed model airplanes [ UKSI14 ], including a wing discretization method tailored to free‐formed bamboo‐copters and an optimization scheme for achieving stable bamboo‐copters considering both spin and flight qualities. 相似文献
68.
Kenichi Asakawa Kensuke Watari Hidetoshi Ohuchi Masahiko Nakamura Tadahiro Hyakudome Yasuhisa Ishihara 《Advanced Robotics》2016,30(1):41-49
A buoyancy engine with a swashplate-type axial piston pump was developed. Its oil extrusion and drawing properties under high hydraulic pressure were evaluated. This buoyancy engine is now installed in an underwater glider that will achieve long-term monitoring of ocean environments up to 2100 m depth in a designated area with lower operational costs. This bidirectionally functioning pump can control the amount of oil in extrusion and draw operations. When drawing oil under high pressure, the hydraulic pump and the electric motor, respectively, act as a hydraulic motor and an electric generator. The generated electric power is absorbed by a damping resistor. The oil-drawing and extrusion properties were measured using a large hyperbaric chamber that is able to produce an almost identical environment to that of actual operations. Results confirmed stable oil extrusion operations up to 21 MPa. Regarding oil-drawing properties, although it was measured only up to 10 MPa in the hyperbaric chamber, it can be inferred that the system can draw the oil and can control the buoyancy precisely up to 21 MPa by replacing the two-way ball valve with an electromagnetic latching solenoid valve. 相似文献
69.
Fengrong LI Takuya IIDA Yoshiharu ISHIKAWA 《Frontiers of Computer Science in China》2008,2(3):257-267
In recent years, peer-to-peer (P2P) technologies are used for flexible and scalable information exchange in the Internet,
but there exist problems to be solved for reliable information exchange. It is important to trace how data circulates between
peers and how data modifications are performed during the circulation before reaching the destination for enhancing the reliability
of exchanged information. However, such lineage tracing is not easy in current P2P networks, since data replications and modifications
are performed independently by autonomous peers—this creates a lack of reliability among the records exchanged. In this paper,
we propose a framework for traceable record exchange in a P2P network. By managing historical information in distributed peers,
we make the modification and exchange histories of records traceable. One of the features of our work is that the database
technologies are utilized for realizing the framework. Histories are maintained in a relational database in each peer, and
tracing queries are written in the datalog query language and executed in a P2P network by cooperating peers. This paper describes
the concept of the framework and overviews the approach to query processing. 相似文献
70.
Nakamura K 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1993,40(6):763-767
The coupled-mode approach is a powerful tool for analyzing surface acoustic wave (SAW) periodic structures such as reflectors and interdigital transducers. The relations among the terminal quantities at two acoustical ports and one electrical port of an interdigital transducer (IDT) are derived from coupled-mode equations. A simple distributed-parameter equivalent circuit representing the entire IDT is proposed. A few examples of applications of this equivalent circuit to analysis of SAW devices are presented. 相似文献