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71.
Location-based services in ubiquitous computing environments 总被引:1,自引:0,他引:1
Ichiro Satoh 《International Journal on Digital Libraries》2006,6(3):280-291
This paper presents a framework for providing dynamically deployable services in ubiquitous computing settings. The goal of
the framework is to provide people, places, and objects with computational functionalities to support and annotate them. Using
RFID-based tracking systems, the framework detects the locations of physical entities, such as people or things, and deploys
services bound to the entities at proper computing devices near where they are located. It enables location-based and personalized
information services to be implemented as mobile agents and operated at stationary or mobile computing devices, which are
at appropriate locations, even if the services do not have any location-information. This paper presents the rationale, design,
implementation, and applications of our prototype infrastructure. 相似文献
72.
Infrared sea surface emissivity including multiple reflection effect for isotropic Gaussian slope distribution model 总被引:1,自引:0,他引:1
Kazuhiko Masuda 《Remote sensing of environment》2006,103(4):488-496
A method is described for incorporating surface-emitted surface-reflected (SESR) radiation into the calculation of infrared sea surface emissivity. Firstly, the direct emissivity is obtained by ignoring SESR emission. Next, the first order SESR emissivity is obtained by using the direct emission as a radiation source. Finally, the ith order SESR emissivity is iteratively obtained by using the i − 1st order SESR emission.Computational results are in good agreement with a Monte Carlo calculation, where the SESR emissivity increases from an emission angle of 50° showing a maximum value of about 0.03 at an emission angle of 80°. The direct emissivity is smaller than the measured emissivity by 0.02∼0.03 around a wavelength of 10 μm at an emission angle of 73.5°. By incorporating the SESR emission into the emissivity model, the discrepancy between the computed and the measured emissivity is significantly reduced.The advantage of the present method over the previous works is that we need not to specify a cutoff angle to differentiate the radiation from the sea and that from the sky for calculating SESR emission. Instead of using a cutoff angle, the probability that radiation originates from the sea is derived from the probability distribution function of sea surface slope. As a result, the uncertainty in the computation of sea surface emissivity attributed to the uncertainty in cutoff angle could be effectively suppressed. 相似文献
73.
Noriaki Kurita Norihiko Fukatsu Teruo Ohashi Satoshi Miyamoto Fumiaki Sato Hiroyuki Nakai Kazuhiko Irie 《Metallurgical and Materials Transactions B》1996,27(6):929-935
We have developed a hydrogen sensor for in situ measurements of hydrogen activities in molten copper. The sensor consists of a concentration cell utilizing a proton conductor,
CaZr0.9In0.1O3-δ, as the solid electrolyte. The electromotive force (emf) of the cell was generated by both hydrogen and oxygen activity gradients
across the cell in a high-temperature region simulating the fire refining processes of copper. However, accurate hydrogen
activity in molten copper could be evaluated from the emf if oxygen activity in molten copper was determined simultaneously
by another concentration cell and if the hydrogen and the oxygen activities at the reference electrode were known. The performance
of the sensor was studied under various conditions. The observed good response and reliability of the sensor show that it
should be a powerful tool for improvement of the fire refining process of the molten copper. Theoretical treatment of the
calculation of the emf of the concentration cells using a mixed ionic conductor, i.e., protonic and oxide ionic conductor, as solid electrolytes is also discussed briefly. 相似文献
74.
K Ohgi K Satoh S Tanaka T Higami T Furukawa H Akiyama S Kimura K Uehara K Murata M Higashi 《Canadian Metallurgical Quarterly》1998,56(11):2854-2858
Artifacts of MR cholangiopancreatography (MRCP) include fluid-filled gastrointestinal tracts, respiratory motion artifacts, spasm of Oddi's sphincter, vascular compression of bile ducts, overlapping of various anatomical structures and bright signal of surrounding fatty tissue. In this article, various technical considerations to eliminate these artifacts were described for the better imaging analysis of MRCP. The use of high-concentration ferric ammonium citrate (Ferriseltz) is recommended to reduce bright signal of fluid-filled gastrointestinal tracts. In case of long breathhold sequences, O2-inhalation study is useful to eliminate respiratory motion artifacts. Careful attention should be paid to the spasm of Oddi's sphincter and the vascular compression of bile ducts to avoid erroneous interpretation of MRCP findings. 相似文献
75.
M Sumi H Satoh M Ohtsuka S Hasegawa M Fujiwara H Kamma 《Canadian Metallurgical Quarterly》1998,5(6):1439-1440
Malignant lymphomas arise in the pleura in association with a long-standing chronic tuberculous pyothorax. We report a case of a non-Hodgkin's lymphoma of the pleural cavity, inoperable because of local invasion into thoracic wall, who has survived more than 6 years without recurrence. This patient represents the longest reported survival after radiation therapy alone. Radiotherapy holds an important role in the treatment of locally advanced lymphoma of the pleural cavity. 相似文献
76.
Summary Series of several alkylated cycloheptanes were detected in some commercial samples of high pressure polyethylene. The structures of the alkylated cycloheptanes were found closely related to the chain transfer agents used in the polymerization process. A probable mechanism involving radical cyclization to cycloheptane structures was presented. 相似文献
77.
Behavior of pseudo-fission products (Ba, Sr, and Zr) as oxides in UO2 has been investigated by means of high-temperature X-ray diffraction and microprobe analysis. Two identifiable compounds were formed as reaction products in the mixed oxides which initially consisted of UO2, BaO, SrO, and ZrO2 powder. These compounds were present and were identified crystallographically as (Ba, Sr) ZrO3 and (Ba, Sr)UO3 after heat treatment of the powders at 1500°C for 30 min. Both compounds are isostructural with perovskite, CaTiO3, and the lattice parameters of both (Ba, Sr)ZrO3 and (Ba, Sr)UO3 decrease with increasing content of Sr. (Ba, Sr)UO3 is decomposed almost completely at 1800°C while (Ba, Sr) ZrO3 is stable up to 2000°C. The behavior of Ba, Sr, and Zr in fuel under irradiation is discussed. 相似文献
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