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101.
MP Fried J Kleefield H Gopal E Reardon BT Ho FA Kuhn 《Canadian Metallurgical Quarterly》1997,107(5):594-601
Image-guided surgery has recently been described in the literature as a useful technology for improved functional endoscopic sinus surgery localization. Image-guided surgery yields accurate knowledge of the surgical field boundaries, allowing safer and more thorough sinus surgery. We have previously reviewed our initial experience with The InstaTrak System. This article presents a multicenter clinical study (n=55) that assesses the system's capability for localizing structures in critical surgical sites. The purpose of this paper is to present quantitative data on accuracy and performance. We describe several new advances including an automated registration technique that eliminates the redundant computed tomography scan, compensation for head movement, and the ability to use interchangeable instruments. 相似文献
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104.
Jean A. Tangeman Brian L. Phillips Robert Hart 《Journal of the American Ceramic Society》2007,90(3):758-762
Containerless liquid-phase processing methods were used to synthesize two glasses, both containing alumina (A), yttria (Y), and lanthana (L), and one containing ∼20 mole% silica (S) as well. In both materials, denoted AYL and AYLS, alumina is the dominant component (>50 mole%), and the lanthana:yttria ratio is ∼2:1. A variety of experimental techniques, e.g. X-ray diffraction, high-field 27 Al magic angle spinning-nuclear magnetic resonance (MAS-NMR), differential scanning calorimetry, and neutron diffraction, were used to analyze both the structure of the amorphous phases resulting from liquid-phase processing and subsequent thermal treatments, and the thermodynamic properties of the as-made and heat-treated materials. The results of the experiments on these glasses and liquids have elucidated the nature of the transitions occurring between the glass transition and crystalline regimes, and have enabled the synthesis of a novel class of alumina-based nanomaterials. 相似文献
105.
Ion beam mixing was used to improve the adhesion between deposited Cu film (400 Å) and polyimide (PI) substrate. Ar+ ion with the energy levels between 180 and 200 keV, and the dose between 1014 to 4 × 1016 ions/cm2 were used. The surface analyses were carried out by Rutherford Backscattering Spectroscopy (SEM). RBS analysis, using 2 MeV He+ ions, showed mixing of Cu and FI and the mixing depended on the Ar+ energy and dose. The X-ray study showed a very broad halo for deposited Cu film but the (111) peak appeared after the Ar+ implantation and the peak increased with Ar+ ion dose. Optical micrographs showed that Cu film formed circular bubbles after many thermal cycles when adhesion was poor and fracture cracks when adhesion was good. 相似文献
106.
Hart Ronald R.; McNeill John W.; Lutz David J.; Adkins Thomas G. 《Canadian Metallurgical Quarterly》1986,17(3):269
[Correction Notice: An erratum for this article was reported in Vol 17(5) of Professional Psychology: Research and Practice (see record 2008-10955-002). In this article, the copyright information was incorrect. The corrected copyright information is included in the erratum.] Examined the clinical correspondence of the full-scale Minnesota Multiphasic Personality Inventory (MMPI) and the MMPI-168 on a psychiatric screening sample of 210 men (mean age 43.27 yrs). The present results fail to replicate previous optimistic findings regarding the worth of the MMPI-168 and accent the need for caution in any further use of this abbreviated instrument. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Hart Robert P.; Kwentus Joseph A.; Wade James B.; Hamer Robert M. 《Canadian Metallurgical Quarterly》1987,55(2):236
Patients with mild dementia of the Alzheimer's type (DAT), patients with major depression, and normal control subjects completed the Wechsler Adult Intelligence Scale (WAIS) Digit Symbol test and a measure of incidental memory for the digit-symbol pairs. Mild DAT and depressed patients had equivalent deficits in psychomotor speed, but DAT patients recalled fewer digit-symbol items. Although the standard administration of the Digit Symbol test has limited utility in differential diagnosis, the addition of a brief measure of incidental memory may be clinically useful as part of the battery of neuropsychological tests used to distinguish early dementia from depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
利用齐次坐标转换法,针对滚齿时刀具与工件切削点的误差建立了六轴滚齿机综合误差数学模型,为便于模型应用于实际直齿加工中,对模型作了进一步简化,并通过采样求出了简化误差数学模型。该模型适用于需要综合考虑各种误差影响,而又不便于测量这些误差的场合。 相似文献
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