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121.
The consolidation of multiple workloads and servers enables the efficient use of server and power resources in shared resource pools. We employ a trace-based workload placement controller that uses historical information to periodically and proactively reassign workloads to servers subject to their quality of service objectives. A reactive migration controller is introduced that detects server overload and underload conditions. It initiates the migration of workloads when the demand for resources exceeds supply. Furthermore, it dynamically adds and removes servers to maintain a balance of supply and demand for capacity while minimizing power usage. A host load simulation environment is used to evaluate several different management policies for the controllers in a time effective manner. A case study involving three months of data for 138 SAP applications compares three integrated controller approaches with the use of each controller separately. The study considers trade-offs between: (i) required capacity and power usage, (ii) resource access quality of service for CPU and memory resources, and (iii) the number of migrations. Our study sheds light on the question of whether a reactive controller or proactive workload placement controller alone is adequate for resource pool management. The results show that the most tightly integrated controller approach offers the best results in terms of capacity and quality but requires more migrations per hour than the other strategies. 相似文献
122.
Background
This research was conducted to explore the relationships between the levels of omega-3 fatty acids in serum phospholipid and key fatty acid ratios including potential cut-offs for risk factor assessment with respect to coronary heart disease and fatal ischemic heart disease. 相似文献123.
Presents an obituary for Brian Mullen. In a field that values empirical precedent and established paradigms, Brian Mullen's career was one of passion and originality. He was motivated by pure intellectual curiosity; the recognition he received for his pioneering work in archival methodology, meta-analysis, and group processes and relations was secondary. His contributions to the field of social psychology were unique and will be enduring. His 1985 book with Robert Rosenthal, BASIC Meta-Analysis: Procedures and Programs, is a classic. In 2006, he was identified as the 15th most cited scholar in social psychology textbooks. Brian died of cancer on May 4, 2006. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
124.
Castro Carl A.; Paylor Richard; Moye Thomas B.; Rudy Jerry W. 《Canadian Metallurgical Quarterly》1990,104(2):390
There are age-related differences in the rat's short-term memory processes. Rats 24–25 days old are 90% correct when the delay interval separating the forced run and choice run of a trial is either 10 or 30 s, but they perform at chance when the delay interval is 60 s. In contrast, the choice performance of 30-day-old rats remains constant across all delay intervals. It is reported that the cholinergic agent physostigmine dramatically improved the short-term-memory-based performance of rats 24–25 days old such that they displayed no loss in choice accuracy even when the delay interval was 60 s. No such enhanced performance was seen in rats treated with neostigmine, a peripherally acting anticholinesterase. The results support the hypothesis that postnatal maturational differences in central cholinergic systems may contribute to age-related differences in short-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
Jerry Riddle 《集成电路应用》2008,(3):45-45
设备制造商和晶圆厂在运营上一直在寻找降低热预算的方法,这样可以提高生产率,降低原材料、设备以及能源的消耗。例如:对于某些外延工艺,工程人员设法在降低反应温度的同时,满足薄膜性能的苛刻要求。这意味着外延工艺将在更快的过程转换中完成,而不是像很多年前,必须将反应腔温度稳定在1000℃以上。然而,随着反应温度的降低,工程人员也发现,在反应腔、压力容器,晶圆输送盒,甚至晶圆上出现了以前没有过的污染物。因此,用户需要开发出可以密切监控污染物的检测方法。 相似文献
126.
Thirty-six depressive subjects were randomly assigned to one of three treatment groups. Group 1 subjects received 60 subliminal presentations of a slide of two figures and the words MOMMY AND I ARE ONE for male subjects and DADDY AND I ARE ONE for female subjects. Group 2 subjects received 60 subliminal slide presentations of a single figure with the words PEOPLE ARE WALKING. Group 3 subjects did not receive a slide. A pretest and posttest Beck Depression Inventory was administered to assess depression increase or decrease. The "subliminal" therapy was carried out over four different sessions. The data show that Group 1 subjects significantly reduced depression scores from pretest to posttest, whereas the subjects in Groups 2 and 3 did not reduce depression scores. Discussion is centered on comparisons of the data with past findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
For the pharmaceutical industry, powder segregation can occur in many processes such as blending and compression solid dose unit operations. Yet it is important that the high quality standards of drug product manufacture are maintained throughout the whole processes. Powder segregation has been identified by the pharmaceutical industry as a potential issue, and in some cases it may cause variability in tablet assay and uniformity throughout a compression run. Early studies suggested for certain Direct Compression (DC) products, the separation of Active Pharmaceutical Ingredient (API) from excipients could arise due to air-induced segregation of the powders discharging from an Intermediate Bulk Container (IBC) to the tablet press via a vertical chute.Segregation tests were carried out on trial powder blend materials supplied by GlaxoSmithKline (GSK), using a laboratory-scale air elutriation test facility at The Wolfson Centre. Particle size analysis of the virgin and segregated sub-samples clearly indicated that powder segregation occurred as a result of aerodynamic effects. Subsequent chemical assay results concurred with the particle size results. Flowability testing of the powder blends indicated them to be free-flowing materials; this in addition to the presence of large particle size differentials within the powder blends is the likely cause of the susceptibility to air-induced segregation. 相似文献
128.
The classification of colorectal cancers (CRC) is currently based largely on histologically determined tumour characteristics, such as differentiation status and tumour stage, i.e., depth of tumour invasion, involvement of regional lymph nodes and the occurrence of metastatic spread to other organs. These are the conventional prognostic factors for patient survival and often determine the requirement for adjuvant therapy after surgical resection of the primary tumour. However, patients with the same CRC stage can have very different disease-related outcomes. For some, surgical removal of early-stage tumours leads to full recovery, while for others, disease recurrence and metastasis may occur regardless of adjuvant therapy. It is therefore important to understand the molecular processes that lead to disease progression and metastasis and to find more reliable prognostic markers and novel targets for therapy. This review focuses on cell surface proteins that correlate with tumour progression, metastasis and patient outcome, and discusses some of the challenges in finding prognostic protein markers in CRC. 相似文献
129.
Andrew A. Wereszczak Timothy P. Kirkland Kevin T. Strong Jr. James Campbell Jerry C. LaSalvia Herbert T. Miller 《International Journal of Applied Ceramic Technology》2010,7(5):635-642
Quasi-static Weibull strength-size scaling of hot-pressed silicon carbide is described. Two surface conditions (uniaxial ground and uniaxial ground followed by grit blasting) were explored. Strength test coupons sampled effective areas from the very small (4 × 10−3 mm2) to the very large (4 × 104 mm2). Equibiaxial flexure and Hertzian ring crack initiation were used for the strength tests, and characteristic strengths for several different specimen geometries were analyzed as a function of effective area. Characteristic strength was found to substantially increase with decreased effective area for both surface conditions. Weibull moduli of 9.4- and 11.7 well-represented strength-size scaling for the two ground conditions between an effective area range of 10−1 and 4 × 104 mm2. Machining damage was observed to be the dominant flaw type over this range. However, for effective areas <10−1 mm2, the characteristic strength increased rapidly for both ground surface conditions as the effective area decreased, and one or more of the inherent assumptions behind the classical Weibull strength-size scaling were in violation in this range. The selections of a ceramic strength to account for ballistically induced tile deflection and expanding cavity modeling are considered in context with the measured strength-size scaling. The observed size-scaling is briefly discussed with reference to dynamic strength. 相似文献
130.