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Hans-Jürgen Odenthal Herbert Pfeifer Ina Lemanowicz Rainer Gorissen 《Metallurgical and Materials Transactions B》2002,33(2):163-172
The present work describes quantitative digital particle image velocimetry measurements of a full-scale water model of a thin
slab mold. Different casting speeds and two submerged entry nozzles with one and two outlet ports have been investigated.
The flow pattern of the single-port nozzle shows a counterclockwise-rotating double vortex that is nearly steady-state but
leads to high stationary surface waves. The flow jets out of the two-port nozzle oscillate and produce a transient flow pattern
with low wave amplitudes. The amplitudes for the one-port nozzle show a linear variation with the volumetric flow rate. The
experimental results lead to a good interpretation of the flow phenomena and are used to validate steady-state numerical simulations
with the commercial program, CFX, on the basis of the Reynolds equations. To describe anisotropic turbulence effects, the
Reynolds stress model (RSM) is used for the flat single-port nozzle and the standard k-ɛ model for the mold flow. The calculated mean velocities and wave amplitudes, predicted from pressure distribution at the
water surface, are generally in the consensus of the experimental data.
An erratum to this article is available at . 相似文献
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The vicissitudes of the Israeli-Palestinian peace process since 1967 are analyzed using attitudes and related concepts where relevant. The 1967 war returned the two peoples' zero-sum conflict around national identity to its origin as a conflict within the land both peoples claim. Gradually, new attitudes evolved regarding the necessity and possibility of negotiations toward a two-state solution based on mutual recognition, which became the building stones of the 1993 Oslo agreement. Lacking a commitment to a final outcome, the Oslo-based peace process was hampered by reserve options, which increased avoidance at the expense of approach tendencies as the parties moved toward a final agreement. The resulting breakdown of the process in 2000 produced clashing narratives, reflecting different anchors for judgment and classical mirror images. Public support for violence increased, even as public opinion continued to favor a negotiated two-state solution. Reviving the peace process requires mutual reassurance about the availability of a partner for negotiating a principled peace based on a historic compromise that meets the basic needs and validates the identities of both peoples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Sood Johanna R.; Cisek Edward; Zimmerman Joan; Zaleski Ellen H.; Fillmore Herbert H. 《Canadian Metallurgical Quarterly》2003,48(1):44
Objective: To replicate and extend P. A. Lichtenberg and colleagues' (1996) cross-disciplinary intervention to improve physical and mental health among older adults. Participants: 14 depressed older adults (6 treatment, 8 control). Setting: The short-term rehabilitation unit of an urban nursing home. Intervention: Occupational therapists were trained to treat depression using pleasant events and cognitive-behavioral therapies. Outcome Measures: Geriatric Depression Scale, the Short Form-12, and the Multi-Level Assessment Instrument: Activities of Daily Living. Results: No significant group differences were found in physical or mental health. However, more control group members (75%) than treatment group members (33%) were depressed at study completion. Conclusions: The treatment of depressive symptoms can be integrated with a nonmental health treatment modality. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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R Zahn A Vogt K Seidl S Schuster H Gülker KW Heinrich M Gottwik K Neuhaus J Senges 《Canadian Metallurgical Quarterly》1997,86(9):712-721
Balloon angioplasty as the treatment of first choice in the setting of an acute myocardial infarction (AMI) is gaining widespread acceptance because of favourable results from specialised centres concerning high patency rates and low mortality. This study reports the results of angioplasty for AMI at large community hospitals during 1992-1995. 4625 procedures were performed at 68 centres of the Arbeitsgemeinschaft Leitender Kardiologischer Krankenhaus?rzte (ALKK). The age of the patients was 60.8 +/- 11.3 years, with 75.1% men. The infarct related artery was the left anterior descendent in 43%, the right coronary artery in 37%, the circumflex artery in 16%, a bypass graft in 2.3% and the left main stem in 1.4% of patients. The success rate (residual stenosis < 50%) of the intervention was 86%. There was a wide range of procedures per centre, with a median of 40 AMI angioplasties per year and centre. The amount of angioplasties for AMI in relation to all angioplasties performed during this period rose from 5.2% in 1992 to 5.9% in 1995 (p = 0.01). Local complications at the puncture site occurred in 3.2%, with the need for a surgical intervention in 1.1% of patients. In 273 (5.9%) of the patients a second angioplasty was performed during the hospital stay. Aortocoronary bypass surgery was performed in 3% of the patients. Hospital mortality was 9.5% (438/4625 patients). The mortality rate remained constant during the years investigated (1992: 10.6%; 1993: 8.6%; 1994: 9.7%; 1995: 9.8%; p = ns). Higher mortality was observed in older patients, patients with multiple vessel disease, the left anterior descending artery or a bypass graft as infarct related artery as well as in patients with failed reperfusion (residual stenoses > 50%). Hospitals with a case load of more than 40 angioplasties for AMI per year showed a lower mortality as compared to the others. In clinical practice at large community hospitals results of angioplasty for AMI concerning mortality, complications and technical success rate are comparable to those of highly specialised centres. The absolute numbers of angioplasties for AMI increased constantly over the years. 相似文献