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221.
As an alternative to the intensity correlation used in conventional speckle metrology, we propose a new technique for displacement observation that is based on spatial-signal-domain phase-only correlation and that makes use of the pseudophase of the complex analytic signal generated from a Hilbert-filtered speckle pattern. Experimental results are presented that demonstrate the validity and the advantage of the proposed signal-domain phase-only correlation technique over both the conventional intensity correlation technique and the spatial-frequency-domain phase-only correlation technique. 相似文献
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The effect of additives on the formation of fine Ti02 particles by vapor phase reaction was studied. The oxygenolysis of TiC14 was enhanced by the addition of Fecl3 , and AlBr3 , and suppressed by SiCl4 , and ZrCl4 . Particles formed in the presence of additives were 1/2 to 1/5 the size of those formed without additives, and particle size distributions became very narrow. Particle shape was also influenced by the additives. 相似文献
224.
Yoko Akama Debra Evans Seth Keen Faye McMillan Mark McMillan Peter West 《Digital Creativity》2017,28(1):58-72
ABSTRACTThe proliferation of digitally mediated DIY practices constitutes new modalities of political expression and participation, shaping how citizenship is enacted and performed. However, our paper begins by problematizing concepts of citizenship in media and communication contexts that only speaks to identity-formation. For Indigenous Australians, citizenship does not need to be asserted or constructed—they are sovereign and they have never ceded their land, rights or identity. Pursuing this argument, we share insights of various digital and creative scaffolds that are being designed with Wiradjuri people as continuous ‘infrastructuring’ to express and practice Wiradjuri sovereignty. This exploration is enabling a political identity to form and creating multiple places to be Wiradjuri together. We also discuss how designing digital and creative scaffolds can be considered as a meeting place of sovereigns, to attend to a consciousness that non-Indigenous people are also practising their own sovereignty in relation to respecting Indigenous sovereignty/ies. 相似文献
225.
Yoko Kumiko Hirokazu Hiroyuki Toshifumi Isao Kohji 《Sensors and actuators. B, Chemical》2009,142(1):28-32
We constructed a wearable and flexible humidity sensor (thickness: 80 μm) in a sandwich configuration, with a hydrophilic poly-tetrafluoroethylene membrane placed between two gold deposited layers, using soft-MEMS techniques. The device was used to measure humidity level, via its electrical conductivity, using a multi-frequency LCR-meter at frequencies ranging from 100 Hz to 100 kHz. The device was calibrated at 100 Hz against moist air over the range of 30–85% RH, which includes normal humidity levels in the atmosphere and physiological air such as breath and evaporating sweat. The response sensitivity of the humidity device was extremely high, even for recovery to dry air; for example response time was less than 1 s for a conductivity shift between humid air of 80% RH and dry air of −60 °C dew point. The sensor performance was reproducible over multiple measurements, with a coefficient of variation of 1.77% (n = 5). The sensor was appropriate for physiological applications, and was successfully used in two non-invasive approaches: to monitor breath air at the mouth, and to measure sweat moisture from the nostrils. 相似文献
226.
Giuliano Freddi Yoko Gotoh Tadasu Mori Ichihiko Tsutsui Masuhiro Tsukada 《应用聚合物科学杂志》1994,52(6):775-781
This work deals with the chemical composition, physical structure, and thermal behavior of Antheraea assama silk fibers. The amino acid composition is characterized by the high content of alanine, glycine, and serine. Among the amino acid residues with polar side chains, aspartic acid, arginine, and tyrosine prevail. The birefrigence and isotropic refractive index values are 0.030 and 1.557, respectively. The stress-strain curve shows a yield point at 5% elongation, followed by a region of gradual extensibility. Blongation at break is about 40%. The X-ray diffraction pattern is typical of β silks, with–(ala)n–repeats in the polypeptide sequences of the crystalline regions. The differential scanning calorimetry curve shows two minor endotherms at 230 and 300°C, before final thermal decomposition at 362°C. The maximum extent of contraction exhibited by the thermomechanical analysis curve is 2%. The surface of degummed fibers shows the presence of longtitudinal strations. The fiber cross section is mostly relliptical. Raw Fibers taken from cocoons show the presence of several crystalline deposits on the surface, identified as crystals of calcium oxalate. © 1994 John Wiley & Sons, Inc. 相似文献
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Preservation of the pelvic plexus in surgery for rectal cancer could shorten the distance between the cancer and the lateral resection margin, whereby the curability of the operation may be reduced. To clarify the indications for preserving the pelvic plexus in such surgery, the relationship of the pelvic plexus to the rectum and rectal cancer was investigated anatomically in 12 autopsied specimens and 12 surgical specimens. The rectum and anus were dissected with all the pelvic organs from autopsied cadavers and transverse sections were prepared at 10-mm intervals after fixation. The location of the pelvic plexus was then measured on the tissue preparations, and compared to that of surgical specimens from rectal cancers with concurrent resection of the pelvic plexus. The pelvic plexus was located from 3.3 +/- 1.2 cm above to 2.3 +/- 1.9 cm below the peritoneal reflection in the autopsied specimens. The average distances between the muscularis propria and the pelvic plexus in the autopsied specimens and surgical specimens were 8.3 +/- 3.5 mm and 14.7 +/- 4.5 mm, respectively, showing a significant difference (P < 0.05). Pelvic plexuses were located about 10 mm from the outer margin of rectal muscularis propria. These findings indicate that concurrent resection of the pelvic plexus may be required to secure sufficient surgical clearance in pT3 rectal cancers, especially those invading deeply beyond the muscularis propria (a2). 相似文献
230.
This paper reports a flexible scanner consisting of a scanning actuator and optical waveguides for medical imaging applications such as endoscopic fluorescence imaging diagnosis. The 0.3-mm-thick and 5-mm-wide functional scanner was designed to be smaller enough than the 10 mm-diameter of channel of endoscope. The proposed device can be used to introduce an excitation light into the abdominal cavity or digestive tract. A pneumatic balloon actuator (PBA) consisting of polydimethylsiloxane (PDMS) is used as the scanning actuator for the scanner in consideration of its small, soft, and safe features. The SU-8 optical waveguides with high refractive index (nSU-8 = 1.575) are integrated onto the PBA structure made of PDMS with a lower refractive index (nPDMS = 1.405). Excitation light at a wavelength of 405 nm is transmitted through an optical fiber to the SU-8 waveguides. The outgoing light from the waveguide can be scanned by the bending motion of the PBA. The waveguide functions as a detector as well. Our developed device has successfully scanned, excited, and detected light from fluorescence beads at a wavelength of 540 nm distributed in a pseudo-tissue. 相似文献