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71.
A method is proposed for modeling the self-pressurization of optical fibers that are sealed before drawing. The model is solved numerically and the results compared with experimental results. An explanation of the mechanism is presented and a numerical investigation is undertaken to optimize the choice of experimental parameters to minimize the transient effects of sealed preform drawing. 相似文献
72.
Improving after-the-fact tracing and mapping: supporting software quality predictions 总被引:1,自引:0,他引:1
The software engineering industry undertakes many activities that require generating and using mappings. Companies develop knowledge bases to capture corporate expertise and possibly proprietary information. Software developers build traceability matrices to demonstrate that their designs satisfy the requirements. Proposal managers map customers' statements of work to individual sections of companies' proposals to prove compliance. Systems engineers authoring interface specifications record design rationales as they make relevant decisions. We developed an approach to tracing and mapping that aims to use fully automated information retrieval techniques, and we implemented our approach in a tool called RETRO (requirements tracing on target). 相似文献
73.
Hayes J.H. Dekhtyar A. Sundaram S.K. 《IEEE transactions on pattern analysis and machine intelligence》2006,32(1):4-19
This paper addresses the issues related to improving the overall quality of the dynamic candidate link generation for the requirements tracing process for verification and validation and independent verification and validation analysts. The contribution of the paper is four-fold: we define goals for a tracing tool based on analyst responsibilities in the tracing process, we introduce several new measures for validating that the goals have been satisfied, we implement analyst feedback in the tracing process, and we present a prototype tool that we built, RETRO (REquirements TRacing On-target), to address these goals. We also present the results of a study used to assess RETRO's support of goals and goal elements that can be measured objectively. 相似文献
74.
E. Hayes 《Water and Environment Journal》2004,18(1):17-19
Woods Mill Lake is the centrepiece of a nature reserve at Henfield in Sussex, UK. During the last forty years, the lake has undergone a succession of changes, and this has resulted in loss of depth and encroachment of the reed-bed. In the summer months the large carp population was suffering stress due to shallow water. The problem of silt excavation required extensive discussion with statutory agencies: in addition, the work had to be scheduled around nesting birds, breeding newts and school visits. This paper (a) discusses the complexity of the work which was undertaken, and (b) provides an analysis of the fish population which was removed from the lake. 相似文献
75.
76.
Hayes Jeffrey A.; McCracken Janet E.; McClanahan Mary K.; Hill Clara E.; Harp Jennifer S.; Carozzoni Paul 《Canadian Metallurgical Quarterly》1998,45(4):468
A consensual qualitative research strategy was used to examine data from 127 interviews conducted with 8 psychologists immediately following their sessions of brief therapy with 8 clients. Analyses revealed 3 domains relevant to countertransference: origins (including categories of family issues, needs and values, therapy specific issues, and cultural issues), triggers (including categories of content of client material, therapist comparing client with others, change in therapy structure or procedures, therapist assessing progress of therapy, therapist perception of client, and emotions), and manifestations (including categories of approach, avoidance, negative feelings, and treatment planning). The frequency of categories within and across cases was classified, and relationships among categories from the 3 domains were detected, generating hypotheses for future empirical research. Implications for practice, training, and continued research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
DA Hullett MT Cantorna C Redaelli J Humpal-Winter CE Hayes HW Sollinger HF Deluca 《Canadian Metallurgical Quarterly》1998,66(7):824-828
BACKGROUND: 1,25-Dihydroxyvitamin D3, the hormonal form of vitamin D, is now believed to play a significant role in the immune responses, both in vitro and in vivo, preventing the development of several autoimmune diseases. These studies suggest that 1,25-dihydroxyvitamin D3 may be effective in prolonging allograph survival. METHODS: To test the hypothesis that 1,25-dihydroxyvitamin D3 would prolong allograft survival, neonatal heart grafts were transplanted to allogeneic recipients receiving either 19-nor-1,25-dihydroxyvitamin D2 (200 ng/day) or 1,25-dihydroxyvitamin D3 (50 ng/mouse/day) orally through the diet. The efficacy of 1,25-dihydroxyvitamin D3 in prolonging graft survival in a vascularized model was determined by heterotopic ACI to Lewis heart transplants. RESULTS: The provision of exogenous 1,25-dihydroxyvitamin D3 or an analog, 19-nor-1,25-dihydroxyvitamin D2, to mice markedly prolonged the survival of neonatal mouse heart allografts. Similar results were obtained with a vascularized heterotopic heart transplant model in rats. Cyclosporine at a maximum 25 mg/kg dose for mice proved less effective than 1,25-dihydroxyvitamin D3. Graft survival in mice differing at class I and class II loci (B10.A(4R) --> C57BL/10) increased from 13.0+/-1.1 days to 51.0+/-5.6 days and was significantly better than cyclosporine monotherapy (33.2+/-3.6). Rat heart survival in a high responder strain combination (ACI --> Lewis) increased from 6.2+/-0.3 to 25.2+/-2.8 days. The increased survival of the transplants brought about with 1,25-dihydroxyvitamin D3 was not accompanied by hypercalcemia in rats. CONCLUSION: These results suggest that 1,25-dihydroxyvitamin D3 can be used as an effective agent in preventing graft rejection. 相似文献
78.
Decarburisation experiments were carried out by levitating liquid iron droplets in a flowing gas stream containing carbon dioxide at 1723K. Decarburisation of liquid iron droplets by carbon dioxide can be adequately described by the mixed control of gas phase mass transport and dissociative chemisorption of carbon dioxide. Carbon monoxide in the gas phase does not have any significant effect on the rate of decarburisation. The rate of decarburisation decreases significantly with increase in sulphur content in the melt and this effect can be quantitatively explained using the Langmuir isotherm. Adsorption coefficient of sulphur is found to be 200. Influence of phosphorus and chromium in the melt on the rate of decarburisation is negligibly small. 相似文献
79.
Glycoproteins play key roles in the development, structuring, and subsequent functioning of the nervous system. However, the complex glycosylation process is a critical component in the biosynthesis of CNS glycoproteins that may be susceptible to the actions of toxicological agents or may be altered by genetic defects. This review will provide an outline of the complexity of this glycosylation process and of some of the key neural glycoproteins that play particular roles in neural development and in synaptic plasticity in the mature CNS. Finally, the potential of glycoproteins as targets for CNS disorders will be discussed. 相似文献
80.
HM Hayes 《Canadian Metallurgical Quarterly》1976,104(6):673-677
Significantly reduced immunoglobulins were found in 22 patients with phenylketonuria. Tests of cellular immune function which included delayed skin hypersensitivity, T rosettes and PHA transformation were normal. Escherichia coli antibodies and the booster response to tetanus toxoid were also normal. 相似文献