391 research outputs found

    Laser fluid velocity detector Patent

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    Doppler shifted laser beam as fluid velocity senso

    Laser Doppler instrument measures fluid velocity without reference beam

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    Fluid velocity is measured by focusing laser beam on moving fluid and measuring Doppler shift in frequency which results when radiation is scattered by particles either originally present or deliberately injected into moving fluid

    Investigation of air-flow velocity by laser backscatter

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    Laser light backscatter investigation of air flow velocity in contaminated atmospheres for application to clear air turbulence detector

    Satellite Attitude Control Utilizing the Earth's Magnetic Field

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    A study was conducted to determine the feasibility of a satellite attitude fine-control system using the interaction of the earth's magnetic field with current-carrying coils to produce torque. The approximate intensity of the earth's magnetic field was determined as a function of the satellite coordinates. Components of the magnetic field were found to vary essentially sinusoidally at approximately twice orbital frequency. Amplitude and distortion of the sinusoidal components were a function of satellite orbit. Two systems for two-axis attitude control evolved from this study, one using three coils and the other using two coils. The torques developed by the two systems differ only when the component of magnetic field along the tracking line is zero. For this case the two-coil system develops no torque whereas the three-coil system develops some effective torque which allows partial control. The equations which describe the three-coil system are complex in comparison to those of the two-coil system and require the measurement of all three components of the magnetic field as compared with only one for the two-coil case. Intermittent three-axis torquing can also be achieved. This torquing can be used for coarse attitude control, or for dumping the stored momentum of inertia reaction wheels. Such a system has the advantage of requiring no fuel aboard the satellite. For any of these magnetic torquing schemes the power required to produce the magnetic moment and the weight of the coil seem reasonable

    Photoemission study of TiO2/VO2 interfaces

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    We have measured photoemission spectra of two kinds of TiO2_2-capped VO2_2 thin films, namely, that with rutile-type TiO2_2 (r-TiO2_2/VO2_2) and that with amorphous TiO2_2 (a-TiO2_2/VO2_2) capping layers. Below the Metal-insulator transition temperature of the VO2_2 thin films, ∼300\sim 300 K, metallic states were not observed for the interfaces with TiO2_2, in contrast with the interfaces between the band insulator SrTiO3_3 and the Mott insulator LaTiO3_3 in spite of the fact that both TiO2_2 and SrTiO3_3 are band insulators with d0d^0 electronic configurations and both VO2_2 and LaTiO3_3 are Mott insulators with d1d^1 electronic configurations. We discuss possible origins of this difference and suggest the importance of the polarity discontinuity of the interfaces. Stronger incoherent part was observed in r-TiO2_2/VO2_2 than in a-TiO2_2/VO2_2, suggesting Ti-V atomic diffusion due to the higher deposition temperature for r-TiO2_2/VO2_2.Comment: 5 pages, 6 figure

    Web API for biology with a workflow navigation system

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    DNA Data Bank of Japan (DDBJ) provides Web-based systems for biological analysis, called Web APIs for biology (WABI). So far, we have developed over 20 SOAP services and several workflows that consist of a series of method invocations. In this article, we present newly developed services of WABI, that is, REST-based Web services, additional workflows and a workflow navigation system. Each Web service and workflow can be used as a complete service or a building block for programmers to construct more complex information processing systems. The workflow navigation system aims to help non-programming biologists perform analysis tasks by providing next applicable services on Web browsers according to the output of a previously selected service. With this function, users can apply multiple services consecutively only by following links without any programming or manual copy-and-paste operations on Web browsers. The listed services are determined automatically by the system referring to the dictionaries of service categories, the input/output types of services and HTML tags. WABI and the workflow navigation system are freely accessible at http://www.xml.nig.ac.jp/index.html and http://cyclamen.ddbj.nig.ac.jp/, respectively

    Scalar Field Contribution to Rotating Black Hole Entropy

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    Scalar field contribution to entropy is studied in arbitrary D dimensional one parameter rotating spacetime by semiclassical method. By introducing the zenithal angle dependent cutoff parameter, the generalized area law is derived. The non-rotating limit can be taken smoothly and it yields known results. The derived area law is then applied to the Banados-Teitelboim-Zanelli (BTZ) black hole in (2+1) dimension and the Kerr-Newman black hole in (3+1) dimension. The generalized area law is reconfirmed by the Euclidean path integral method for the quantized scalar field. The scalar field mass contribution is discussed briefly.Comment: 26 page

    Classical and Quantum Solutions and the Problem of Time in R2R^2 Cosmology

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    We have studied various classical solutions in R2R^2 cosmology. Especially we have obtained general classical solutions in pure R2R^2\ cosmology. Even in the quantum theory, we can solve the Wheeler-DeWitt equation in pure R2R^2\ cosmology exactly. Comparing these classical and quantum solutions in R2R^2\ cosmology, we have studied the problem of time in general relativity.Comment: 17 pages, latex, no figure, one reference is correcte

    Disrupted White Matter Integrity and Structural Brain Networks in Temporal Lobe Epilepsy With and Without Interictal Psychosis

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    Background: Despite the importance of psychosis as a comorbidity of temporal lobe epilepsy (TLE), the underlying neural mechanisms are still unclear. We aimed to investigate abnormalities specific to psychosis in TLE, using diffusion MRI parameters and graph-theoretical network analysis. Material and Methods: We recruited 49 patients with TLE (20 with and 29 without interictal schizophrenia-like psychosis) and 42 age-/gender-matched healthy controls. We performed 3-tesla MRI scans including 3D T1-weighted imaging and diffusion tensor imaging in all participants. Among the three groups, fractional anisotropy (FA), mean diffusivity (MD), and global network metrics were compared by analyses of covariance. Regional connectivity strength was compared by network-based statistics. Results: Compared to controls, TLE patients showed significant temporal and extra-temporal changes in FA, and MD, which were more severe and widespread in patients with than without psychosis. We observed distinct differences between TLE patients with and without psychosis in the anterior thalamic radiation (ATR), inferior fronto-occipital fasciculus (IFOF), and inferior longitudinal fasciculus (ILF). Similarly, for network metrics, global, and local efficiency and increased path length were significantly reduced in TLE patients compared to controls, but with more severe changes in TLE with psychosis than without psychosis. Network-based statistics detected significant differences between TLE with and without psychosis mainly involving the left limbic and prefrontal areas. Conclusion: TLE patients with interictal schizophrenia-like psychosis showed more widespread and severe white matter impairment, involving the ATR, IFOF and ILF, as well as disrupted network connectivity, particularly in the left limbic and prefrontal cortex, than patients without psychosis
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