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排序方式: 共有1599条查询结果,搜索用时 15 毫秒
991.
Henry Schultz John Alexander Jim Petersen Thomas Hartmann Doug Overland Bill Gigante Peter Grandsard 《Journal of The Association for Laboratory Automation》2003,8(1):24-27
Automation of large-scale compound storage, biological and chemical assays, and many other biopharmaceutical R&D processes have prompted the need for immediate and regular determination of equipment performance levels. The Automatic Metric Monitoring Program (AMMP) in Amgen Research is designed to fill this need. Standardized tests are performed at regular intervals with results instantaneously retrieved, analyzed, and stored in a database. Critical information is automatically tracked using control charts allowing immediate notification via e-mail alerts when problems or nonconforming performance is discovered. System usage and errors are automatically compiled with tabulated results provided at regular intervals and e-mail alarms issued for nonconforming operation. AMMP now provides researchers with needed real-time feedback on the performance of their automation systems. 相似文献
992.
We consider an extension of the classical resource-constrained project scheduling problem (RCPSP), which covers discrete resource-resource and time-resource tradeoffs. As a result a project scheduler is permitted to identify several alternatives or modes of accomplishment for each activity of the project. The solution procedure to be presented is a considerable generalization of the branch-and-bound algorithm proposed by Demeulemeester and Herroelen, which is currently the most powerful method for optimally solving the RCPSP. More precisely, we extend their concept of delay alternatives by introducing mode alternatives. The basic enumeration scheme is enhanced by dominance rules which increase the performance of the algorithm. We then report on our computational results obtained from the comparison with the most rapid procedure reported in the literature. 相似文献
993.
With 23 postmenopausal and 33 premenopausal females the interactions between circadianic secretion patterns of estradiol, growth hormone, IGF I, prolactin, DHEA-S as well as cortisol and the amount and distribution of subcutaneous body fat, estimated by using 10 absolute body measures and 10 anthropometric indices were tested. Premenopausal and postmenopausal women differed regarding the secretion patterns of estradiol and growth hormone significantly from each other. Furthermore it turned out, that the daily secretion rate, estimated by using the area under the curve, of growth hormone and estradiol correlated significantly with the amount and the distribution of body fat. In both proband groups more corpulent women had lower growth hormone levels and higher estradiol levels. The age dependent reduction of growth hormone secretion may be co-responsible for the general weight gain with increasing age. The reduced estrogen secretion however, seems to be the major determinant of the expression of a more masculine type of fat distribution during climacteric and after the menopause. 相似文献
994.
995.
R Grunwald U Griebner E T Nibbering A Kummrow M Rini T Elsaesser V Kebbel H J Hartmann W Jüptner 《Journal of the Optical Society of America. A, Optics, image science, and vision》2001,18(11):2923-2931
Small-angle, noncollinear, first- and second-order interferometric autocorrelation experiments with Ti:sapphire laser pulses of 9-80-fs duration have been performed with microaxicon arrays. Predictions of short-pulse spatial frequency effects were verified by comparison of interference patterns of single elements and matrices. An angular spectrum of Gaussian-shaped axicons was analyzed on the basis of linear refraction. Experimental data indicate contributions to autocorrelation by nonlinear refraction and travel-time differences. The influence of the spectral bandwidth was separated from the pulse-duration-dependent effects. Spatially resolved information about the coherence time was delivered by the multichannel structure. 相似文献
996.
Zusammenfassung Performancesteigerung ist beim Einsatz von RDBMS ein Kernthema. W?hrend h?ufig noch detailliertes Know How der RDBMS-Architektur
und Erfahrung dafür erforderlich sind, werden von einzelnen Datenbankherstellern Instrumente angeboten, die dem Administrator
die notwendigen Analysen weitestgehend abnehmen. Dies wird am Beispiel von Adabas D und den Werkzeugen x_wizard und Diagnose
Monitor gezeigt.
Eingegangen am 28.10.1996, in überarbeiteter Form am 04.03.1997 相似文献
997.
R. B. Heimann H. V. Tran P. Hartmann 《Materialwissenschaft und Werkstofftechnik》2003,34(12):1163-1169
The structure and phase composition of HAp coatings deposited onto Ti6Al4V coupons (50x20x2mm) by atmospheric plasma spraying (APS) were studied by laser‐Raman spectroscopy, 31P‐ and 1H‐MAS‐NMR and 2D‐31P/1H HETCOR‐CP‐NMR spectroscopy, and XRD with Rietveld refinement. The samples investigated comprised APS HAp coatings with and without a TiO2 bond coat as well as coatings incubated for different lengths of time (up to 12 weeks) in simulated body fluid (SBF) under physiological conditions. In APS coatings the presence of a bond coat increased the proportion of well‐ordered crystalline HAp at the expense of distorted apatite‐like structures such as oxyHAp and oxyapatite, and thermal decomposition products such as tricalcium phosphate (TCP) and tetracalcium phosphate (TTCP), and also decreased the amount of amorphous calcium phosphate (ACP). Incubation in SBF further advanced the proportion of crystalline HAp since the disordered structures, the thermal decomposition products, and ACP exhibit substantially higher solubility. 相似文献
998.
K Midtvedt A Hartmann J Hjelmesaeth K Lund BL Bjerkely 《Canadian Metallurgical Quarterly》1998,13(2):427-431
The DNA sequences of two related plasmids pPR1 and pPR3 described previously in Streptococcus pneumoniae isolates from Germany and Spain were now determined. Both plasmids belong to a family of rolling circle (RC) plasmids found in a variety of bacteria. Their GC content with 32% is lower than that of the S. pneumoniae chromosomal DNA. The plasmid pPR3 has a molecular size of 3160 bp with four putative open reading frames, whereas pPR1 contained a deletion of 313 bp that included the 5'-part of ORF2 and upstream regions and differed by three bp from pPR3. The predicted protein of ORF1 showed high similarity to replication proteins of RC plasmids with 74% identical amino acids to RepA of Streptococcus thermophilus plasmids. Sequences similar to the plus origin of replication of ssDNA plasmids were present in both plasmids. They also contained a 152-bp region with over 83% identity to the minus origin of replication of the Streptococcus agalacticae plasmid pMV158. 相似文献
999.
1000.