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41.
Don Chambers 《Journal of Automated Methods and Management in Chemistry》1994,16(4):135-137
It is generally believed that successful robot users have dedicated
centralized robotic groups. While such a generalization holds some
merit historically, the availability of newer more user-friendly robots
and workstations in recent years and a more computer-literate work
force today is changing the way that automation can be managed.
Decentralization recognizes robots and workstations as additional
tools for all analysts, not a select few. Such an approach initiates
involvement and education of more staff with respect to automation.
This further ushers the development of automated methods instead
of the automation of manually-developed methods. Decentralization
also provides local control of resources to address the priorities of
a specific functional group within the department. Both a vision of
the future, as well as a look at the past, should be considered when
determining how to manage robotic and other means of automation.
This paper discusses decentralized management of robots as
currently applied and envisioned in a large pharmaceutical
analytical R & D department. 相似文献
42.
James Rodgers Kaye Wolf Norm Willis Don Hamilton Ralph Ledbetter Curtis Stewart 《Color research and application》1994,19(5):322-331
A multiplant Quality Improvement Team [QIT] was firmed to develop and implement an evaluation program for various color measurement .systems as potential replacements for the then-current aging systems. The emphasis qf this article is the analytical methodology utilized to evaluate the various color systems. The evaluation program consisted cf two phases. Phase I was a general overview/review of several systems, while Phase II was an extensive internal comparative evaluation measurement systems. These were Milton-Roy's ColorMate HDS, HunterLab's Ultrascan, Datacolor's CS-5, and BYK-Gardner's The Color Sphere [TCS]. The main comparison criteria were interinstrument agreement [agreement between two instruments ofthe same system], user-friendly software and computer interface capability, vendor amenability to a long-term logistical and maintenance relationship, and price. All systems were evaluated by duplicate measurements on various color tiles, yarns, and polymer flakes-over 1600 measurements on each system. The systems were compared with an instrument matrix, a decision matrix, and a product matrix. The instrument matrix was a comparison qfinstrument parameters, software/math treatments, and economics. The decision matrix was a forced ranking of each system by each criteria category [1–4 scale, with 1 representing the best and 4 representing the worst]. The product matrix accentuated the relative importance ofone criterion category over another by multiplying the forced ranking by the criticality of the category. The criticality of a given category wus determined by consensus within the QIT. Thr combination qf the three matrices allowed the evaluator[.s] t o select the color rneasuremmt system that best satixfied the color measurement needs and requirements of their facility and their products. For this evaluation, all ofthe evaluated systems were superior to the then-current agingsystems. As a result of this methodology, one instrument emerged as clearly superior. © 1994 John Wrley & Sons, Inc. 相似文献
43.
H. Khim Boo Bela K. Mikofalvy James W. Summers W. Alan Sell Don H. Mittendorf 《乙烯基与添加剂工艺杂志》1992,14(3):140-144
The separation of PVC from contaminants is one of the most important steps in recycling PVC. Earlier works have shown that one can separate PVC from other polymers by using the X-ray fluorescence technique. However, in many cases, even after careful separation, there is a remaining impurity level of about 0.1% due to the limitations of the separation processes. In many applications, impurities, particularly nonmeltables, cause defects in the PVC matrix and must be removed for best performance and appearance. Melt filtration appears to be the best technique to remove the nonmeltable impurities. 相似文献
44.
Variation in repeated nucleotide sequences (RNSs) at the level of entire families assayed by Southern blot hybridization is remarkably low within species and is a powerful tool for scrutinizing the origin of allopolyploid taxa. Thirty-one clones from RNSs isolated from different Triticeae genera were used to investigate the genome constitution of South American Elymus. One of these clones, pHch2, preferentially hybridized with the diploid H genome Hordeum species. Hybridization of this clone with a worldwide collection of Elymus species with known genome formulas showed that pHch2 clearly discriminates Elymus species with the H genome (StH, StHH, StStH, and StHY) from those with other genome combinations (StY, StStY, StPY, and StP). Hybridization with pHch2 indicates the presence of the H genome in all South American Elymus species except Elymus erianthus and Elymus mendocinus. Hybridization with additional clones that revealed differential restriction fragments (marker bands) for the H genome confirmed the absence of the H genome in these species. Differential restriction fragments for the Ns genome of Psathyrostachys were detected in E. erianthus and E. mendocinus and three species of Leymus. Based on genome constitution, morphology, and habitat, E. erianthus and E. mendocinus were transferred to the genus Leymus. 相似文献
45.
H Reznik-Wolf TA Treves M Davidson J Aharon-Peretz PH St George Hyslop J Chapman AD Korczyn B Goldman E Friedman 《Canadian Metallurgical Quarterly》1996,98(6):700-702
Germline mutations in the presenilin 1 (PS1) gene apparently account for the majority of early-onset, familial Alzheimer's disease (AD). Using a mutation-screening strategy (denaturing gradient gel electrophoresis; DGGE), we analyzed a large family with early onset AD and seizures. The patients in this family showed a novel missense mutation in exon 5 of the PS1 gene (A to T change in codon 120, altering glutamine to aspartic acid). This novel mutation is located within the second hydrophilic domain of the molecule, a region not particularly involved in previously described germline mutations, and is of unknown biological significance. These results also demonstrate that DGGE can be used effectively to screen for mutations within this gene. 相似文献
46.
P Barrett G Davidson DG Hazlerigg MA Morris AW Ross PJ Morgan 《Canadian Metallurgical Quarterly》1998,139(1):163-171
47.
This study investigates within-subject variations and associations of salivary viscosities and flow rates in a test panel of healthy adults. After several practice sessions, unstimulated and stimulated whole saliva samples were collected 5 times daily (at 0800, 1100, 1400, 1700, and 2000 h) from 30 university students. There was a significant within-subject variation in viscosity and flow rate of unstimulated saliva (P<0.001). Intra-item correlations were significantly different for salivary flow rates (r= 0.82 for unstimulated, r= 0.88 for stimulated, P< 0.001) and viscosity of unstimulated saliva (r= 0.54, P< 0.05), but viscosity of stimulated saliva was different in this respect. Our results indicate that there is a significant within-subject variation in viscosity of unstimulated saliva. 相似文献
48.
Reward only is not enough: Evaluating and improving the fairness policy of the P2P file sharing network eMule/eDonkey 总被引:1,自引:0,他引:1
Yunzhao Li Don Gruenbacher Caterina Scoglio 《Peer-to-Peer Networking and Applications》2012,5(1):40-57
Limiting the threat of free-riding behavior is an important design issue for peer-to-peer (P2P) file sharing networks. However,
the fairness policy that rewards contributors with credit in one of the most popular P2P file sharing networks, eMule/eDonkey,
hasn’t been thoroughly studied. In this paper, motivated by our experiments with the eMule/eDonkey network, we firstly theoretically
analyze the content exchange process with credit in eMule/eDonkey and then verify the mathematical model by an agent-based
simulation. Both the numerical and simulation-based results confirm our discovery in the experiments that eMule/eDonkey’s
local credit strategy can not provide enough fairness as it doesn’t explicitly punish free-riders. To overcome this drawback,
we propose a new free-riding control scheme, which can simply maintain the current credit local structure and take advantage
of the credit policy. Extensive numerical evaluation and simulation indicate that this scheme significantly improves system
fairness. 相似文献
49.
Requirements Engineering - To reduce program risks, engineering methods capitalizing on modeling and machine assistance have been extensively investigated within systems engineering (and more... 相似文献
50.
Several related algorithms are presented for computing logarithms in fieldsGF(p),p a prime. Heuristic arguments predict a running time of exp((1+o(1))
) for the initial precomputation phase that is needed for eachp, and much shorter running times for computing individual logarithms once the precomputation is done. The running time of the precomputation is roughly the same as that of the fastest known algorithms for factoring integers of size aboutp. The algorithms use the well known basic scheme of obtaining linear equations for logarithms of small primes and then solving them to obtain a database to be used for the computation of individual logarithms. The novel ingredients are new ways of obtaining linear equations and new methods of solving these linear equations by adaptations of sparse matrix methods from numerical analysis to the case of finite rings. While some of the new logarithm algorithms are adaptations of known integer factorization algorithms, others are new and can be adapted to yield integer factorization algorithms. 相似文献