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Nishiyama H.,Tohoku University | Kudoh D.,Tohoku University | Kato N.,NTT East Corporation | Kadowaki N.,Japan National Institute of Information and Communications Technology
Proceedings of the IEEE | Year: 2011

While GEostationary Orbit (GEO) satellite systems provide us with a wide coverage area, their long delay serves as a significant constraint for real-time applications. On the other hand, Low Earth Orbit (LEO) satellite systems are best suited to delay sensitive applications. However, the coverage and mobility issues of LEO satellites lead to relatively high management costs. In this paper, we devise a new load balancing and quality of service (QoS) provisioning scheme to accommodate both real-time and non-real-time traffic based on a new congestion-prediction scheme. The effect of this new scheme is expected to improve the efficiency of the GEO/LEO hybrid satellite networks and the QoS satisfaction of end users. © 2011 IEEE.

Takahashi M.,Sapporo Medical University | Takahashi M.,NTT East Corporation | Yamada G.,Sapporo Medical University | Koba H.,Teine Keijin kai Hospital | Takahashi H.,Sapporo Medical University
Open Respiratory Medicine Journal | Year: 2012

Introduction: Centrilobular emphysema (CLE) is recognized as low attenuation areas (LAA) with centrilobular distribution on high-resolution computed tomography. The LAA often exhibit a variety of shape or sharpness of border. This study was performed to elucidate the relationship between morphological features of LAA and pathological findings in CLE. Materials and Methods: The inflated-fixed lungs from 50 patients with CLE (42 males, 8 females; 14 operated, 36 autopsied) were examined by a method of CT-pathologic correlations that consisted of three steps. The first, CT images of the sliced lungs of the inflated-fixed lung specimens were examined on the shape and the peripheral border of each LAA. The second, the sliced lungs were radiographed in contact with high magnification. The third, the surface of the sliced lungs was observed by using stereomicroscopy. The views at low magnification of stereomicroscope were compared with the radiographs and the CT images of the same sample. Results: Using CT-pathologic correlations, LAAs of CLE were classified into three types as follows; round or oval shape with well-defined border (Type A), polygonal or irregular shape with ill-defined border and less than 5 mm in diameter (Type B), and irregular shape with ill-defined border and 5 mm or over in diameter (Type C). Type A, Type B and Type C LAA were mainly related to dilatation of bronchioles, destruction of proximal part of alveolar ducts, and destruction of distal part of alveolar ducts, respectively. Type A, Type B and Type C were dominant LAA in 5 (10%), 29 (58%) and 12 (24%) patients, respectively. However, remained 4 patients (8%) did not show dominant LAA type. Conclusion: Morphological features of LAA in CLE may depend on dilatation or destruction of certain parts of the secondary lobule. Type B LAA was the commonest type in CLE. © Takahashi et al.

Masugi M.,Ritsumeikan University | Hirasawa N.,Nippon Telegraph and Telephone | Akiyama Y.,NTT East Corporation | Murakawa K.,Nippon Telegraph and Telephone
IEICE Transactions on Communications | Year: 2012

To clarify the characteristics of high-speed electrostatic discharge (ESD) events, we use two kinds of discharge electrodes: sphereand cylinder-shape ones. We measure the energy level of ESD waveforms with charging voltages of 0.25, 0.5, and 1.0 kV. We find that the cylindrical electrode yields higher high-speed ESD energies, especially when the charging voltage is high; this indicates that the discharge gap shape is an important factor in ESD events. Copyright © 2012 The Institute of Electronics, Information and Communication Engineers.

Tanaka Y.O.,University of Tsukuba | Okada S.,University of Tsukuba | Yagi T.,University of Tsukuba | Satoh T.,University of Tsukuba | And 4 more authors.
American Journal of Roentgenology | Year: 2010

OBJECTIVE. Although mural nodules are considered to be the most important hallmark in the recognition of ovarian cancers accompanied with endometriotic cysts, benign neoplasms and even inflammatory diseases can show similar MRI findings. We sought to clarify the MRI characteristics of malignancy accompanied with endometriotic cysts of the ovary. MATERIALS AND METHODS. Contrast-enhanced MRI was performed and endometriosis was pathologically confirmed in 49 patients with endometriotic cysts displaying mural nodules. Malignancy was pathologically diagnosed in 33 patients and benignity, in 16. Clinical data including patient age and MRI findings in terms of the size of the endometriotic cysts, number of loculi, presence of shading of the cysts, size of the mural nodules, signal intensity of the mural nodules on T1- and T2-weighted images, and contrast enhancement of the mural nodules were retrospectively reviewed. Statistical analysis of each parameter used the Mann-Whitney U test. RESULTS. The mean age of the patients and mean size of the endometriotic cysts were significantly higher in patients with a malignant condition than in those with a benign condition. Contrast enhancement of the mural nodules was observed in 97% of malignant and 44% of benign tumors. The size of the mural nodules was significantly larger in patients with a malignant condition than in those with a benign condition. Differences in size between the bilateral diseases, multilocularity, existence of shading, and the signal intensities of mural nodules were not significantly different between the malignant and benign conditions. CONCLUSION. Endometriotic cysts with enhanced mural nodules are not always complicated with malignancy. In elderly patients, the presence of large enhanced nodules on large endometriotic cysts is more likely to indicate malignancy. © American Roentgen Ray Society.

Takeshita Y.,Nippon Telegraph and Telephone | Sawada T.,Nippon Telegraph and Telephone | Handa T.,Nippon Telegraph and Telephone | Watanuki Y.,Nippon Telegraph and Telephone | Kudo T.,NTT East Corporation
Progress in Organic Coatings | Year: 2012

Properties such as the specular gloss, adhesive strength, viscoelasticity, and impact resistance of thermoplastic polyester powder coating film were studied as a function of air-cooling time. Thermoplastic polyester resin is known for the fact that the heating condition has an effect on the degree of crystallinity. We focused on the relationship between the air-cooling time employed in the film preparation process and the degree of crystallinity. The test pieces were dipped into a fluidized polyester powder vessel, and then cooled in air to form the film. We refer to this cooling time in air as the "air-cooling time". It was found that the degree of crystallinity increased as the air-cooling time increased. As the degree of crystallinity increased, the specular gloss, adhesive strength, viscosity and impact resistance decreased. We therefore found that the improvement in film performance is related to the reduction in the air-cooling time. The importance of this phenomenon is considered in relation to the widespread use of thermoplastic polyester resin. Similar behavior is expected for other polyester powder coatings. © 2012 Published by Elsevier B.V. All rights reserved.

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