69 research outputs found

    Piezoelectric Vibration Energy Harvester Using Polyvinylidene Difluoride Film Formed by Bar-Coating Method and Its Spray- Coating Method on a Three Dimensional Surface

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    A cantilever-type vibration energy harvester (VEH) made of polyvinylidene difluoride (PVDF) was fabricated and characterized. PVDF is one of the polymer piezoelectric materials, which is more flexible than ceramic-based piezoelectric materials such as lead zirconate titanate (PZT). The fabrication process of VEH is as follows: a PVDF film was coated on a phosphor bronze plate by bar-coating method, followed by polarization by corona discharge method. Aluminum top electrode was deposited on the PVDF film by sputtering. One end of the plate was clamped by a fixture to form a cantilever, the length of which is 25 mm. Output power P at the resonance frequency (=55 Hz) was measured as a function of load resistance R with the acceleration set at 17 m/s2. Maximum output reached 4.3 μW at R = 2.1 MΩ. This result is not inferior compared with other reported VEHs using ceramic piezoelectric material. Spray coating was carried out to form PVDF film on a 3D surface. This method is suitable for fabricating a uniform thin film on a three-dimensional (3D) surface, even if it is complicatedly curved. In this study, PVDF film was formed on a 3D helical compressing spring, and the deposition on it was successfully achieved

    超音波を用いた移動体の自動追尾システムの開発

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    金沢大学工学部研究課題/領域番号:04750197, 研究期間(年度):1992出典:研究課題「超音波を用いた移動体の自動追尾システムの開発」課題番号04750197(KAKEN:科学研究費助成事業データベース(国立情報学研究所)) (https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-04750197/)を加工して作

    Brain Abscess as a Rare Complication of Primary Extranodal Nasal-type Natural Killer/T-cell Lymphoma

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    We present the case of a 58-year-old Japanese woman with a natural killer T (NK/T)-cell lymphoma complicated by brain abscess. NK/T-cell lymphomas represent a rare type of lymphoma derived from either activated NK cells or, rarely, cytotoxic T cells. They are aggressive Epstein-Barr virus (EBV)-associated lymphomas that involve mainly the nasal cavity. Brain abscess associated with primary extranodal nasal-type NK/T-cell lymphoma is extremely uncommon: to our knowledge, this is the first reported case of this lymphoma with brain abscess as the initial clinical manifestation. Endoscopic surgery was performed for definitive diagnosis under intraoperative navigation system. Chemotherapy followed by radiotherapy was performed and was effective: 72 months later the tumor has not recurred. Recommendations of endoscopic management for diagnosis and treatment of this rare neoplasm are discussed

    Case Report Carbon Ion Beam Radiotherapy for Sinonasal Malignant Tumors Invading Skull Base

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    Objective. To evaluate the treatment outcome and prognostic factors in patients with sinonasal malignant tumors invading skull base. Study Design and Setting. A retrospective clinical study at the Yamagata University School of Medicine. Subjects and Methods. Three patients with sinonasal malignant tumors invading skull base were presented in present study. All patients were treated with carbon ion beam radiotherapy. The prescribed dose to the center of the clinical target volume was 64.0 GyE/16 fractions over 4 weeks at 4.0 GyE/fraction per day. Results. All patients completed carbon ion beam radiotherapy without an interval. The mean observation period was 39.6 months (range: 11-54 months). There were no local or regional recurrences in all cases; however, one patient had a metastasis in distant organs. Regarding the complications, visual loss was observed in one eye of one patient whose optic nerve was entirely involved by the tumor and field of carbon ion beam radiotherapy. Radiation induced brain injury was observed in two patients; however, these patients do not complain about neurological abnormality and had no treatment for radiation induced brain necrosis. Conclusions. Carbon ion beam radiotherapy for sinonasal malignant tumors invading the skull base showed therapeutic effectiveness

    Human Detection by Fourier descriptors and Fuzzy Color Histograms with Fuzzy c-means method

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    It is difficult to use histograms of oriented gradients (HOG) or other gradient-based features to detect persons in outdoor environments given that the background or scale undergoes considerable changes. This study involved the segmentation of depth images. Additionally, P-type Fourier descriptors were extracted as shape features from two-dimensional coordinates of a contour in the segmentation domains. With respect to the P-type Fourier descriptors, a person detector was created with the fuzzy c-means method (for general person detection). Furthermore, a fuzzy color histogram was extracted in terms of color features from the RGB values of the domain surface. With respect to the fuzzy color histogram, a detector of a person wearing specific clothes was created with the fuzzy c-means method (specific person detection). The study includes the following characteristics: 1) The general person detection requires less number of images used for learning and is robust against a change in the scale when compared to that in cases in which HOG or other methods are used. 2) The specific person detection gives results close to those obtained by human color vision when compared to the color indices such as RGB or CIEDE. This method was applied for a person search application at the Tsukuba Challenge, and the obtained results confirmed the effectiveness of the proposed method.A part of the study was financially supported by Promotion Grant for Higher Education and Resech 2014 at Kansai University under the title "Tsukuba Challenge and RoboCup @ Home."平成26年度関西大学教育研究高度化促進

    つくばチャレンジ2019における関西大学の自律移動ロボットの開発

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    本研究の一部は,平成28年度関西大学教育研究高度化推進費において,研究課題「ロボット競技会をモチベーションとしたソフトウェアに力点を置いたメカトロニクス教育」として研究費を受けた

    Development and application of an ultra-miniaturized blood collecting/testing system by MEMS

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    This report outlines research, supported by a Kansai University special fund (2004). Collecting blood and sending it to a given destination is inevitable in micro-TAS application for the purpose of this research. Development of a micro-needle made of biodegradable polymer and a method for collecting blood with this micro-needle, evaluation of bloodstream characteristics in a micro-channel, and development of supporting technology for collecting and analyzing blood are discussed in this paper. In each case, successful new technologies were developed
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