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101.
Let Γ be an arrangement of pseudo-lines, i.e., a collection of unbounded x -monotone curves in which each curve crosses each of the others exactly once. A pseudo-line graph (Γ, E) is a graph for which the vertices are the pseudo-lines of Γ and the edges are some unordered pairs of pseudo-lines of Γ . A diamond of a pseudo-line graph (Γ, E) is a pair of edges {p,q} , {p',q'}∈ E , {p,q} ∩ {p',q'}= , such that the crossing point of the pseudo-lines p and q lies vertically between p' and q' and the crossing point of p' and q' lies vertically between p and q . We show that a graph is planar if and only if it is isomorphic to a diamond-free pseudo-line graph. An immediate consequence
of this theorem is that the O(k
1/3
n) upper bound on the k -level complexity of an arrangement of straight lines, which was very recently discovered by Dey, holds for an arrangement
of pseudo-lines as well. 相似文献
102.
We have developed a technology for a robot that uses an indoor navigation system based on visual methods to provide the required
autonomy. For robots to run autonomously, it is extremely important that they are able to recognize the surrounding environment
and their current location. Because it was not necessary to use plural external world sensors, we built a navigation system
in our test environment that reduced the burden of information processing mainly by using sight information from a monocular
camera. In addition, we used only natural landmarks such as walls, because we assumed that the environment was a human one.
In this article we discuss and explain two modules: a self-position recognition system and an obstacle recognition system.
In both systems, the recognition is based on image processing of the sight information provided by the robot’s camera. In
addition, in order to provide autonomy for the robot, we use an encoder and information from a two-dimensional space map given
beforehand. Here, we explain the navigation system that integrates these two modules. We applied this system to a robot in
an indoor environment and evaluated its performance, and in a discussion of our experimental results we consider the resulting
problems. 相似文献
103.
[This corrects the article on p. 1930 in vol. 11, PMID: 20480050.]. 相似文献
104.
M Utsumi K Moriguchi H Takahashi C Kinoshita A Togari M Mizutani N Ohno 《Journal of electron microscopy》1999,48(2):139-145
The ultrastructure of the parathyroid gland (PTG) of the UM-X7.1 cardiomyopathic hamster (the UM-X7.1) was qualitatively and quantitatively compared with that of the normal hamster. In the UM-X7.1, the Golgi apparatus and rER were well developed compared with those of the control hamster. Morphometric analysis revealed that the mean values of the Golgi apparatus, rER and large vacuolar bodies were significantly greater in the UM-X7.1 than in the normal hamster and the mean value of lipid droplets was significantly less in the UM-X7.1 than in the normal hamster. Ultrastructurally, we consider that in the UM-X7.1, the synthesis and release of the parathyroid hormone may be activated by an excessive amount of circulating catecholamine, and the functional activity of the PTG may be higher than that in the normal hamster. 相似文献
105.
Yasushi Nishiwaki Hisao Yamashita Yoshihide Honda Yuichiro Kimura Hayami Fujimori 《The International journal of environmental studies》2013,70(1-4):277-289
The levels of 90Sr and 137Cs in human placenta, fetus and diet were determined by radiochemical methods during the period from March 1966 to December 1968. The possible effects of these radionuclides on the pregnant woman and the fetus were discussed. The metabolic characteristics of both 90Sr and 137Cs were also discussed on the basis of estimates of discrimination factors and observed ratios of these radionuclides. As a result of the analyses, the dose rate to the human placenta resulting from deposition of 90Sr in the organ was estimated at about 0.003 mrem/month and that of 137Cs at about 0.013 mrem/month. The dose rate to the total body resulting from the body burden of these radionuclides in the mother was estimated at about 0.012 mrem/ month. These values are much smaller than the monthly dose from 40K normally existing in the body. It was rather difficult to draw definitive conclusions concerning the possible correlation between the 90Sr fallout and the annual changes of infant mortality rates in Japan. 相似文献
106.
107.
Both President Peter Reynolds and Secretary General Glenn Stout attended the IWRA Regional Seminar on Water Quality and its Management in New Delhi, India on December 10–11, 1985. Over 100 members and fellow water scientists and administrators attended. Leading Indian water authorities participated in the program. We reproduce here the inaugural address by Shri B. Shankaranand, Union Minister for Water Resources, and a summary of the Conclusions and Recommendations. 相似文献
108.
Hidetoshi Miyazaki Shin-ichi Kikitsu Hisao Suzuki Toshitaka Ota 《Advanced Powder Technology》2011,22(4):544-547
In an effort to improve energy-efficient windows, we experimented with a precursor slurry composite by using needle-like TiO2 particles as the filler in a urethane matrix. Applying dc bias to the slurry failed to array the needle-like particles in the composite and to deposit on the film surface because of electrophoretic movement. However, applying ac bias of ±5 V to the precursor slurry composite for 12 h resulted in the needle-like TiO2 particles being arrayed in the composite in a direction normal to the film surface. This resulted in an improvement in the energy efficiency of the material through an angular dependence of transmittance in the visible–near-infrared range. 相似文献
109.
Kinoshita Kengo; Sadanami Keishi; Kidera Akinori; Go Nobuhiro 《Protein engineering, design & selection : PEDS》1999,12(1):11-14
In order to search for a common structural motif in the phosphate-bindingsites of proteinmononucleotide complexes, we investigatedthe structural variety of phosphate-binding schemes by an all-against-allcomparison of 491 binding sites found in the Protein Data Bank.We found four frequently occurring structural motifs composedof protein atoms interacting with phosphate groups, each ofwhich appears in different protein superfamilies with differentfolds. The most frequently occurring motif, which we call thestructural P-loop, is shared by 13 superfamilies and is characterizedby a four-residue fragment, GXXX, interacting with a phosphategroup through the backbone atoms. Various sequence motifs, includingWalker's A motif or the P-loop, turn out to be a structuralP-loop found in a few specific superfamilies. The other threemotifs are found in pairs of superfamilies: protein kinase andglutathione synthetase ATPase domain like, actin-like ATPasedomain and nucleotidyltransferase, and FMN-linked oxidoreductaseand PRTase. 相似文献
110.
A simple common-collector full-monolithic preamplifier is developed using an advanced 3 ?m Si-bipolar IC technology SICOS. The amplifier characteristics are a 650 MHz bandwidth and a 5.2 pA/?(Hz) equivalent input noise current at a 3 k? transimpedance. Measured optical sensitivity of a front end consisting of the amplifier and a Ge-APD is ?36.2 dBm for an error rate of 10?9 at a 560 Mbit/s bit rate and 1.3 ?m wavelength. 相似文献