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991.
Bill Parker 《Coloration Technology》1993,109(12):382-384
The basic principles of finishing both woollen and worsted fabrics have changed very little in 50 years, but the speed and control of many processes have changed beyond recognition in many cases. In this article, Bill Parker looks at the techniques in use today. 相似文献
992.
Properties of objects and spatial relations between objects play an important role in rule-based approaches for high-level vision. The partial presence or absence of such properties and relationships can supply both positive and negative evidence for region labeling hypotheses. Similarly, fuzzy labeling of a region can generate new hypotheses pertaining to the properties of the region, its relation to the neighboring regions, and, finally, hypotheses pertaining to the labels of the neighboring regions. A unified methodology that can be used to characterize both properties and spatial relationships of object regions in a digital image is presented. The methods proposed for computing the properties and relations of image regions can be used to arrive at more meaningful decisions about the contents of the scene 相似文献
993.
994.
M Aprahamian S Evrard P Keller M Tsuji G Balboni C Damgé J Marescaux 《Canadian Metallurgical Quarterly》1993,8(2):101-114
The in vivo administration and distribution of a potent new photosensitizer, pheophorbide A (PH-A), was investigated in rats. The spectral characteristics were determined. This hydrophobic compound was solubilized by an ethanol/phosphate-buffered saline (PBS) mixture (v/v) and sonicated immediately before i.v. administration. Tissue distribution and the affinity of PH-A for an acinar pancreatic tumor were determined in Lewis rats for up to 48 h after a single i.v. administration of 3 mg kg-1 body wt. Methanol-extracted PH-A was quantitatively determined by fluorescence spectrophotometry at 665.6 nm. The PH-A uptake pattern showed that the reticulo-endothelial system is the major target of PH-A, followed by the gut and then the lung and pancreas. PH-A concentrations in skin were very low. The presence of an enterohepatic cycle was suggested by the PH-A biliary output, intestinal uptake and blood concentrations. Tumor PH-A retention was longer than pancreatic retention. The ratio of tumoral to peri-tumoral pancreas PH-A was 6.7:1, 24 h after i.v. administration. With its similar tissue pattern, better absorption spectrum and lower skin toxicity, PH-A could be a more potent photosensitizer than hematoporphyrin derivatives. 相似文献
995.
Mason Robert A.; Just Marcel Adam; Keller Timothy A.; Carpenter Patricia A. 《Canadian Metallurgical Quarterly》2003,29(6):1319
Two fMRI studies investigated the time course and amplitude of brain activity in language-related areas during the processing of syntactically ambiguous sentences. In Experiment 1, higher levels of activation were found during the reading of unpreferred syntactic structures as well as more complex structures. In Experiments 2A and 2B higher levels of brain activation were found for ambiguous sentences compared with unambiguous sentences matched for syntactic complexity, even when the ambiguities were resolved in favor of the preferred syntactic construction (despite the absence of this difference in previous reading time results). Although results can be reconciled with either serial or parallel models of sentence parsing, they arguably fit better into the parallel framework. Serial models can admittedly be made consistent but only by including a parallel component. The fMRI data indicate the involvement of a parallel component in syntactic parsing that might be either a selection mechanism or a construction of multiple parses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
997.
John R. Serrano B.Sc. Dennis Berger B.Sc. Bill Bridges Jr. 《JOM Journal of the Minerals, Metals and Materials Society》1994,46(10):12-14
This article describes quality-control work at Phelps Dodge, undertaken as part of ISO 9003 certification, to better identify and prevent the contamination of copper cathodes by bismuth. It also overviews the implementation of a production control system as well as associated training designed to minimize the possibility of bismuth-contaminated copper progressing beyond the cathode stage to other areas of manufacturing or distribution. 相似文献
998.
Gregory J. McCarthy Lindsay P. Keller Paul J. Schields Mark P. Elless Keven C. Galbreath 《Cement and Concrete Research》1984,14(4):479-484
A lignite coal ash produced in a low-Btu atmospheric pressure gasifier has been studied by X-ray diffraction. The ash was dominantly crystalline and consisted of CaOMgONa2O-silicates (melilite, merwinite, Ca2SiO4-bredigite, nepheline/carnegieite), oxides (ferrite spinel, quartz, periclase, hematite), phases formed by reaction with water or precipitation from solutions used in ash handling (calcite, portlandite, brucite, thenardite, ettringite, gypsum, goethite) and several additional trace phases (plagioclase, pyroxene, cristobalite, serpentine and talc). 相似文献
999.
Bill Holdsworth 《Refocus》2004,5(2):28-30
The ground is as universal as air and solar radiation. Over the past twenty years, as the hunt for natural low-carbon energy sources has intensified, there has been an increased endeavour to investigate and develop both earth and ground water thermal energy storage and usage. Bill Holdsworth reports on some recent pioneering developments in the Netherlands and UK. 相似文献
1000.
EK Butker DJ Helton JW Keller LL Hughes T Crenshaw LW Davis 《Canadian Metallurgical Quarterly》1996,23(10):1809-1814
A method was devised to simulate patients with breast cancer in the actual treatment position utilizing a diagnostic CT spiral scanner, 3-D Image Workstation for virtual simulation, and a laser coordinate system to transfer planning parameters to the patient's skin. It was desired to produce non-divergent tangential beams through the lung as well as a matched line for tangential and supraclavicular fields. The patients were immobilized in an Alpha CradleTM cast. Radio-opaque markers were placed on the superior, inferior, medial, and lateral margins of the field so as to afford appropriate initial field set-up approximations. The patient was scanned. The data set was then transferred to the workstation where an isocenter was chosen. The patient was marked. Virtual simulation was then performed. This method employed a half beam technique for the posterior edge of the tangential fields. Table rotation and blocking of the superior margin of the tangential fields were used to produce a vertical edge to match a supraclavicular field. Using a beam's eye view the lateral tangent was matched to the medial exit. A digitally reconstructed radiograph was created to define the tangent fields and place the supraclavicular block. Our initial experience with 50 patients verifies that this is a reproducible and accurate technique. Time required for immobilization and tangential field simulation is approximately 30 minutes. Data is available for 3-D treatment planning or 2-D treatment planning on a reconstructed transverse slice angled to match the collimator angle through the patient. Using a CT simulator for simulation of breast cancer affords accuracy of at least equal magnitude to conventional simulators as determined by beam films and ease of set-up. This technique also affords greater ease in changing treatment parameters without having to resimulate the patient. 相似文献