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951.
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We present a three-dimensional (3D) measurement and imaging based on a multicamera system. In the presented system, projected images of 3D objects are taken by cameras located at random positions on a circumference, and then the 3D objects can be reconstructed numerically. We introduce an angle correction function to improve the quality of the reconstructed object. The angle correction function can correct the angle error caused by the position errors in the projected images due to the finite pixel size of the image sensor. The numerical results show that the point source was reconstructed successfully by introducing the angle correction function. We also demonstrate experiments: the two objects are located on a rotary stage controlled by a computer, the projected images are taken by a single camera, and by using 33 projected images, the two objects are reconstructed successfully. 相似文献
954.
Randles AB Esashi M Tanaka S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2010,57(11):2372-2380
This paper presents the etch rate of lithium niobate (LiNbO(3)) as a function of crystal orientation. Etching is a fundamental technology needed for the fabrication of new sensors, actuators, and other new devices. In this study, LiNbO(3) spheres 30 mm in diameter were etched in hydrofluoric acid and a mixture of hydrofluoric and nitric acids at different temperatures and different times. The measured data of the etched sphere shape were processed and plotted, giving etch rate diagrams over the entire spheres. Based on the etch rate data obtained, the Wulff-Jaccodine method was used to predict the etched shape of 128° Y-cut and 155° Y-cut LiNbO(3). The predicted etching profiles were compared with those obtained by experiments. A least-square polynomial fit for the data was also developed and was found to be useful in removing some of the variation in the measurements. 相似文献
955.
The effect of small dose of topiroxostat on serum uric acid in patients receiving hemodialysis 下载免费PDF全文
Yume Nagaoka Yoshiko Tanaka Hiroshi Yoshimoto Rie Suzuki Kakei Ryu Mio Ueda Minako Akiyama Miho Nagai Yoshitaka Miyaoka Eiichiro Kanda Shinnichi Iwai Michio Nagaoka Yoshihiko Kanno 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(3):388-393
Introduction : Topiroxostat, a recently developed xanthine oxidase inhibitor, is expected to have fewer adverse effects than allopurinol because it has different mechanism of action from alloprinol. However, its dosage, usage and safety have not been established in patients with impaired renal function or those undergoing dialysis at the development since no studies was conducted in these patients. Methods : Cross over clinical trial using 3 months of allopurinol and topiroxostat on 27 maintain Japanese HD patients were carried out. The effects on oxidative stress status of both drugs were also evaluated by measuring oxidation reduction potential. Findings : Twenty‐five of twenty‐seven patients completed study. The mean serum uric acid levels in the topiroxostat‐treated arm was significantly lower than it in the allopurinol‐treated arm time‐dependently (P < 0.0001). Corrected oxidative stress ratio defined as biological antioxidant potential/diacron reactive oxygen metabolites was significantly increased in topiroxostat‐arm (*P = 0.0035), but not in allopurinol‐arm (P = 0.1429). No significant difference was seen in diacron reactive oxygen metabolites, biological antioxidant potential, static oxidation‐reduction potential, and capacity oxidation‐reduction potential between pre and post treatment of both drugs. Discussion : It is suggested that a low dose of topiroxostat decreased serum uric acid sufficiently to maintain it below 7.0 mg/dL in patients receiving hemodialysis. 相似文献
956.
957.
The present study aimed to produce small-diameter grafts made of a silk fibroin by electrospinning. In order to reinforce the electrospun silk fibroin graft (ES), the graft was coated with a silk sponge (ESSC). Physical properties such as a diameter of the electrospun silk fibers were influenced by a concentration of fibroin solution. Ultimate tensile strength (UTS) of the ESSC graft was improved compared to the ES graft. However, the ESSC graft was less compliant than the ES graft. Importantly, water permeability of the ESSC graft was within the range of which endothelialization was promoted in previous studies. 相似文献
958.
This paper describes a study of the test specimen thickness effect on fracture toughness of a material, in the transition temperature region, for CT specimens. In addition we studied the specimen thickness effect on the T33-stress (the out-of-plane non-singular term in the series of elastic crack-tip stress fields), expecting that T33-stress affected the crack-tip triaxiality and thus constraint in the out-of-plane direction. Finally, an experimental expression for the thickness effect on the fracture toughness using T33-stress is proposed for 0.55% carbon steel S55C. In addition to the fact that T33 (which was negative) seemed to show an upper bound for large B/W, these results indicate the possibility of improving the existing methods for correlating fracture toughness obtained by test specimen with the toughness of actual cracks found in the structure, using T33-stress. 相似文献
959.
K. Maehata N. Iyomoto T. Yasumune M. Maeda S. Matsumura T. Hara K. Mitsuda N. Yamasaki K. Tanaka 《Journal of Low Temperature Physics》2012,167(3-4):226-231
A 3×3+1 superconducting transition-edge sensor (TES) microcalorimeter-array has been developed for the energy dispersive spectrometer performed on a transmission electron microscope. For increasing sensitive area, each TES microcalorimeter consisted of a Ti/Au bilayer and a mushroom shaped absorber. The mushroom shaped absorber is made from a Au layer of 0.5?μm thick. Geometrical dimensions of the surface area of the TES and the absorber are 350?μm×350?μm and 330?μm×330?μm, respectively. The absorber stem of 150?μm×150?μm in the cross sectional area is deposited on the center of the TES surface. A Ta2O5 insulating layer of 0.1?μm thick is inserted between the overhang layer of the absorber and the TES surface. One pixel of the TES microcalorimeter was operated for detecting X-ray photons emitted from an 55Fe source. 相似文献
960.
Beta-ray skin dose due to the fission fallout from the Hiroshima atomic bomb is potentially related to the epilation in the black rain area. The absorbed dose to the skin from beta-rays emitted by fission fallout has been estimated for an initial 13?Cs deposition of 1 kBq m?2 on the ground at 0.5 h after the explosion. The estimated skin dose takes into account both external exposure from fission fallout radionuclides uniformly distributed in 1 mm of soil on the surface of the ground and from a 26 μm thickness of contaminated soil on the skin, using the Monte Carlo radiation transport code MCNP-4C. The cumulative skin dose for 1 month after the explosion is taken as the representative value. The estimated skin dose for an initial 13?Cs deposition of 1 kBq m?2 was determined to be about 500 mSv. 相似文献