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1.
We discuss some different ideas about the sort of formalism appropriate for translation (more specifically, transfer) that have been explored within Eurotra. The intention is not to evaluate these different ideas, but to outline the issues of general interest and relevance that they raise. Section 1 describes some common assumptions, section 2 describes the different ways they have been interpreted, and section 3 considers some further implications. 相似文献
2.
M. D. Beard M. J. S. Lowe 《International Journal of Rock Mechanics and Mining Sciences》2003,40(4):527-536
The research outlined in this paper is aimed at the development of a portable non-destructive testing instrument for evaluating the condition of rock bolts. In applications such as coal mine roof reinforcement, the opportunities for rock bolt inspection are currently limited to destructive techniques such as the pull-out test. It is proposed that guided ultrasonic waves can be used to solve this inspection problem, using a pulse-echo test carried out from the free end of the bolt. Suitable test frequencies have been identified through the use of modelling software, and successful laboratory and site trials have been undertaken. The research has shown that the proposed approach is capable of determining the bolt length, and of identifying major defects such as necking, deformation, and loss of resin encapsulation. 相似文献
3.
Bufferless distributed circuit (BDC) broadcasting is proposed as a technique for broadcasting high-speed chip input signals to a series of on-chip destination cells as needed in crosspoint switch, parallel multiplier, distributed amplifier, etc., chip designs. In contrast with conventional techniques that use an on-chip buffer to assist broadcasting, BDC broadcasting offers the advantage of lower signal delay and power dissipation. In an experimental GaAs heterojunction bipolar transistor (HBT) 8×4 crosspoint switch assembly, BDC broadcasting was found to achieve a 40% power savings with little or no penalty in jitter or bit error rate performance at a 10-Gb/s data rate 相似文献
4.
Alpidem, an imidazopyridine that acts at the gamma-aminobutyric acid/benzodiazepine receptor complex, has been reported to be an effective anxiolytic with a more favorable side effect profile than benzodiazepines. The effect of alpidem was investigated in an 8-week, open, clinical trial in 13 patients with panic disorder, with or without agoraphobia. Three patients were responders (much improved or very much improved), five patients were nonresponders, and five patients dropped out after less than 6 weeks of treatment. Significant improvement was seen in the sample as a whole for spontaneous panic attacks, phobic avoidance, and anticipatory anxiety. Most improvement occurred during the first 4 weeks of treatment, and responders had milder panic disorder at baseline. Adverse effects were generally mild. After 8 weeks of treatment, taper of medication over 2 weeks occurred without significant worsening of panic disorder symptoms. The efficacy of alpidem in the treatment of panic disorder remains uncertain and requires assessment in a controlled trial. 相似文献
5.
A. Lowe 《Journal of Materials Science》1996,31(4):1005-1011
The transverse compressive behaviour of a structurally complex carbon-epoxy unidirectional composite (T300/914) has been investigated over various temperatures and test rates. The mechanical behaviour was found to mirror the transverse tensile behaviour of the material, with the viscoelastic response being different between micro- and macroproperties. Composite macrofracture was found to occur at ±34 ° to the loading axis and was regular, whereas fracture of the bulk resin was irregular and occurred by Poisson forces, rather than compressive forces. The performance of the test fixture was assessed and found to be adequate for composites testing. An optimum specimen gauge length was determined as the ASTM recommendation was found to be unsatisfactory. 相似文献
6.
Fitting parameterized three-dimensional models to images 总被引:11,自引:0,他引:11
Model-based recognition and motion tracking depend upon the ability to solve for projection and model parameters that will best fit a 3-D model to matching 2-D image features. The author extends current methods of parameter solving to handle objects with arbitrary curved surfaces and with any number of internal parameters representing articulation, variable dimensions, or surface deformations. Numerical stabilization methods are developed that take account of inherent inaccuracies in the image measurements and allow useful solutions to be determined even when there are fewer matches than unknown parameters. The Levenberg-Marquardt method is used to always ensure convergence of the solution. These techniques allow model-based vision to be used for a much wider class of problems than was possible with previous methods. Their application is demonstrated for tracking the motion of curved, parameterized objects 相似文献
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9.
In this study, rat dermal fibroblasts were used as a model system to examine the ability of ligands that are known to activate protein kinase-C to regulate the levels of the mRNAs encoding basic fibroblast growth factor (bFGF) and insulin-like growth factor-I (IGF-I), two growth factors that are thought to be important in processes such as tissue repair and regeneration and wound healing. Treatment of fibroblasts with the phorbol ester phorbol 12-myristate 13-acetate (PMA), thrombin, bradykinin, serotonin, angiotensin-II, or bombesin increased protein kinase-C activity to a similar degree. Treatment of fibroblasts with 1 microM serotonin transiently increased bFGF mRNA levels about 3-fold compared to the level in control cells maintained in serum-free medium with 0.25% BSA and decreased IGF-I mRNA levels by approximately 50% compared to the level in control cells. This is similar to the previously described changes induced by bradykinin in these cells, but different from the more marked and sustained changes induced by thrombin and PMA. In contrast, angiotensin-II and bombesin had no effect on bFGF or IGF-I mRNA levels. The effects of serotonin, bradykinin, and PMA on bFGF and IGF-I mRNA levels were abrogated by preincubation of cells in 250 nM PMA to down-regulate protein kinase-C. In contrast, the effect of thrombin on bFGF mRNA levels was only partially inhibited by down-regulation of protein kinase-C, while its effect on IGF-I mRNA levels was unaffected. The activation of signaling pathways by the different ligands was further investigated to begin to determine the mechanism for the differences in the effects of thrombin vs. serotonin and bradykinin and in the effects of these three ligands vs. angiotensin-II and bombesin. All of the ligands activated phospholipase-D to a similar degree, suggesting that activation of this enzyme was not responsible for the differential effects of the ligands. In contrast, thrombin, serotonin, and bradykinin had marked effects on the hydrolysis of phosphatidylcholine and phosphatidylinositol, whereas bombesin and angiotensin-II had a small effect on phosphatidylcholine hydrolysis and no effect on phosphatidylinositol hydrolysis.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
10.
The prevalence of several paraneoplastic syndromes associated with ovarian cancer was determined from a clinicopathological study of 908 patients with primary ovarian malignancy in the North East Thames Region. The diversity and rarity of these manifestations are great and the explanation for them is difficult. Circumstantial evidence suggests that in some cases an autoimmune phenomenon is the most plausible cause. 相似文献