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1.
Storage performance-metrics and benchmarks 总被引:2,自引:0,他引:2
Chen P.M. Patterson D.A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1993,81(8):1151-1165
The metrics and benchmarks used in storage performance evaluation are discussed. The technology trends taking place in storage systems, such as disk and tape evolution, disk arrays, and solid-state disks, are highlighted. The current popular I/O benchmarks are then described, reviewed, and run on three systems: a DECstation 5000/200 running the Sprite Operating System, a SPARCstation 1+ running SunOS, and an HP Series 700 (Model 730) running HP-UX. Two approaches to storage benchmarks-LADDIS and a self-scaling benchmark with predicted performance-are also described 相似文献
2.
DJ Patterson 《Canadian Metallurgical Quarterly》1994,23(2):313-325
Postgastrectomy syndromes are uncommon but, unfortunately, frustrating for both patient and physician, because treatment with prokinetic agents is often of limited benefit. This article examines the evidence for efficacy of available prokinetic drugs in the management of these difficult disorders. 相似文献
3.
4.
Hovius Marjolijn; Kellenbach Marion L.; Graham Kim S.; Hodges John R.; Patterson Karalyn 《Canadian Metallurgical Quarterly》2003,17(1):100
The authors investigated the impact of semantic knowledge on visual object analysis by assessing the performance of patients with semantic dementia on a different-views object matching test and on 2 object decision tests differing, for example, in whether the nonreal items were nonsense objects or chimeras of 2 real objects. On average, the patients scored normally on both the object matching and the object decision test including nonsense objects but were impaired on the object decision test including chimeras; this latter was also the only visual object test that correlated significantly with degree of semantic impairment. These findings demonstrate that object decision is not a single task or ability and that it is not necessarily independent of conceptual knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Emily S. Patterson David D. Woods Richard I. Cook Marta L. Render 《Cognition, Technology & Work》2007,9(3):155-162
Resilience, the ability to adapt or absorb disturbance, disruption, and change, may be increased by team processes in a complex,
socio-technical system. In particular, collaborative cross-checking is a strategy where at least two individuals or groups
with different perspectives examine the others’ assumptions and/or actions to assess validity or accuracy. With this strategy,
erroneous assessments or actions can be detected quickly enough to mitigate or eliminate negative consequences. In this paper,
we seek to add to the understanding of the elements that are needed in effective cross-checking and the limitations of the
strategy. We define collaborative cross-checking, describe in detail three healthcare incidents where collaborative cross-checks
played a key role, and discuss the implications of emerging patterns. 相似文献
6.
SK Patterson JA Tworek MA Roubidoux MA Helvie HA Oberman 《Canadian Metallurgical Quarterly》1997,169(3):709-712
OBJECTIVE: The objective of this study was to describe the mammographic appearance with pathologic correlation of metaplastic carcinoma of the breast. CONCLUSION: Metaplastic carcinomas of the breast are masses with mammographic characteristics of low suspicion because of their histologic appearance. Metaplastic carcinoma should be included in the differential assessment of predominately circumscribed, noncalcified masses revealed on mammography. One salient feature that may distinguish metaplastic carcinomas is the occurrence of a circumscribed portion with a spiculated portion, which is seen in carcinomas that have a significant mixture of metaplastic and invasive carcinoma growth patterns. 相似文献
7.
Two patients are presented where internal mammary artery grafting was performed for the relief of symptomatic coronary artery disease. At follow-up the internal mammary artery was occluded and a communication between the internal mammary vein and the native coronary artery was demonstrated. These patients were characterised by the early recurrence of angina or the appearance of a continuous murmur. Both patients were treated by re-operation with ligation of the arterio-venous fistula and saphenous vein grafting. 相似文献
8.
From the rhizomes of Polygonatum alte-lobatum, two new homologous series of 1,4-benzoquinones, polygonaquinones A and B, a novel homoisoflavanone, a new gentrogenin glycoside and 13 known compounds were isolated and characterized. The structures of the new compounds were determined as two homologous series of three 2,5-dihydroxy-3-methyl-6-alkyl-1,4-benzoquinones and three 2-hydroxy-3-methyl-6-alkyl-1,4-benzoquinones, with chain lengths C21 to C23, and 4',5,7-trihydroxy-6,8-dimethylhomoisoflavanone and gentrogenin 3-O-beta-D-glucopyranosyl(1-->2)-[beta-D-xylopyranosyl(1-->3)] -beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside. 相似文献
9.
V Kamath CN Jones JC Yip BB Varasteh AH Cincotta GM Reaven YD Chen 《Canadian Metallurgical Quarterly》1997,20(11):1697-1701
OBJECTIVE: To assess the effect on various aspects of carbohydrate and lipid metabolism of administering a quick-release formulation of bromocriptine (Ergoset) to obese, nondiabetic, hyperinsulinemic women. RESEARCH DESIGN AND METHODS: Hourly concentrations of prolactin, glucose, insulin, free fatty acid (FFA), and triglyceride were measured for 24 h before and after approximately 8 weeks of treatment with Ergoset. In addition, fasting lipid and lipoprotein concentrations and the steady-state plasma glucose (SSPG) concentration in response to a continuous infusion of somatostatin, insulin, and glucose were determined before and after Ergoset administration. RESULTS: Circulating prolactin concentrations were dramatically decreased (P < 0.001) following treatment, associated with a significant fall (P < 0.05) in 24-h-long plasma glucose, FFA, and triglyceride concentrations. Neither circulating plasma insulin concentrations nor the ability of insulin to mediate glucose disposal changed with treatment. Finally, fasting total cholesterol fell (P < 0.05) and the ratio of total to HDL cholesterol decreased (P = 0.06) in association with Ergoset treatment. CONCLUSIONS: The fact that significant metabolic improvement was seen in the obese nondiabetic hyperinsulinemic women studied suggests that Ergoset could be of therapeutic benefit in clinical conditions of hyperglycemia and/or dyslipidemia. 相似文献
10.
The years of the great depression were marked with unemployment and economic ruin for many people. Americans were left feeling helpless and hopeless. After the 1932 presidential election of Franklin Roosevelt, his administration embarked on a course of government known as the New Deal. Many new and innovative programs were established to create jobs and a sense of hope for the public. This article will examine four programs that were of particular interest to nursing: the Federal Emergency Relief Act, the Civil Works Act, the Works Progress Act, and the Social Security Act. Nurses of the time embraced these programs. They participated in their development and implementation and made a difference in the lives of many desperate Americans. 相似文献