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排序方式: 共有332条查询结果,搜索用时 15 毫秒
1.
We propose an abstract approach to the problems of common divisors and common multiples of rational matrix functions which (in the case of matrix polynomials) have been studied before using Vandermonde and resultant matrices.Supported in part by the Office of Naval Research, Air Force Office of Scientific Research, and the National Science Foundation.The work of this author was partially supported by an NSF grant and was carried out while visiting the University of California, San Diego. 相似文献
2.
Rubber Tired Gantry Cranes (RTGCs) are the most widely used pieces of equipment in the Hong Kong sea-freight container yards. Workload distribution in the yard changes continuously over time. The dynamic deployment of RTGCs is an important issue in yard operation management. This paper investigates the dynamic crane deployment problem with the objective of determining the crane deployment frequency and routes over a planning horizon to minimize the total workload overflow. The problem is formulated as a mixed integer programming model. A heuristic algorithm is then developed to solve problems of practical sizes. The heuristic quickly finds a near optimal solution for crane deployment operation. 相似文献
3.
Allen Karen; Linn Richard T.; Gutierrez Horacio; Willer Barry S. 《Canadian Metallurgical Quarterly》1994,39(1):29
Investigated burden experienced by 60 spouses and 71 parents who served as primary caregivers to individuals with traumatic brain injury (BI). Burden levels, as assessed by the Questionnaire on Resources and Stress (QRS-SF), were compared for spouses and parents. Both parents and spouses exhibited high levels of burden. Relative to spouses, parents reported significantly greater burden related to lifespan care. Spouses reported significantly less personal reward than did parents. The presence of social aggression and cognitive disability in the individual with BI was found to have a greater association with subjective burden of caregivers than was the presence of physical disability or injury severity. Results of previous studies with QRS-SF scores show that the responsibility assumed by spouses and parents of persons with BI was as great as that experienced by families of people with severe chronic physical disabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Leiba Rodman 《Systems & Control Letters》1992,19(6):475-480
Pole shifting of multivariable control system
over finite dimensional real algebras is studied. The main results are expressed in terms of the minimal polynomial of A + BF, where F is a feedback. 相似文献
5.
Vandermonde and resultant matrices: An abstract approach 相似文献
6.
Saeidi R. Mohammadi H.R.S. Ganchev T. Rodman R.D. 《IEEE transactions on audio, speech, and language processing》2009,17(2):344-353
Recently, we introduced the sorted Gaussian mixture models (SGMMs) algorithm providing the means to tradeoff performance for operational speed and thus permitting the speed-up of GMM-based classification schemes. The performance of the SGMM algorithm depends on the proper choice of the sorting function, and the proper adjustment of its parameters. In the present work, we employ particle swarm optimization (PSO) and an appropriate fitness function to find the most advantageous parameters of the sorting function. We evaluate the practical significance of our approach on the text-independent speaker verification task utilizing the NIST 2002 speaker recognition evaluation (SRE) database while following the NIST SRE experimental protocol. The experimental results demonstrate a superior performance of the SGMM algorithm using PSO when compared to the original SGMM. For comprehensiveness we also compared these results with those from a baseline Gaussian mixture model-universal background model (GMM-UBM) system. The experimental results suggest that the performance loss due to speed-up is partially mitigated using PSO-derived weights in a sorted GMM-based scheme. 相似文献
7.
Noei Maziar Luckner Paul Linn Tobias Jungemann Christoph 《Journal of Computational Electronics》2022,21(1):153-168
Journal of Computational Electronics - We discuss the numerical aspects of the Boltzmann transport equation (BE) for electrons in semiconductor devices, which is stabilized by Godunov’s... 相似文献
8.
Zhang A Robbins PS Averill AL Weber DC Linn CE Roelofs WL Villani MG 《Journal of chemical ecology》2003,29(7):1635-1642
Hoplia equina LeConte (Coleoptera: Scarabaeidae: Melolonthinae) is a beetle pest of cranberry beds in Massachusetts. Larvae feed on the roots of the cranberry plant, reducing yield as well as vine density. The female sex pheromone was identified as 2-tetradecanone. There were eight compounds found in the airborne volatiles collected from females that elicited antennal responses from males. Of the eight compounds tested (nonanal, decanal, dodecanal, 2-dodecanone, 2-tridecanone, 2-tetradecanone, 2-pentadecanone, and 2-hexadecanone), 2-tetradecanone was the only one that attracted male beetles in the field. Combining any of the other seven antennally active compounds with 2-tetradecanone did not increase male capture. 相似文献
9.
10.
目的 制备并评价产肠毒素大肠埃希氏菌(ETEC)标准物质。方法 分别用基质辅助激光解吸电离(MALDI-TOF MS)、生化、16 s RNA基因序列测定三种方法确认菌株种属。采用冷冻干燥技术制备600个ETEC标准样品(103CFU/样品);从中随机抽取20个进行均匀性检验;模拟25℃和37℃的运输温度测试样品的运输稳定性,同时在4℃和-20℃的条件下进行保藏稳定性检验。组织3家实验室对样品进行协同验证。最后选择20件食品基质来验证样品的使用效果。结果 生化、MALDI-TOF MS、16 s RNA基因序列鉴定CMCC(B)43208为大肠埃希氏菌,lt、stp、sth基因确认其为ETEC。均匀性检验中,单因素方差分析得F=1.48,小于FINV(0.05,19,20)。稳定性检验中,在25℃和37℃保藏7 d后结果为103CFU/样品,在-20℃保藏60 d和4℃保存28 d后结果为103CFU/样品。协同标定实验中,3家实验室检测样品中菌株均为ETEC(103CFU/标准样品)。使用效果评价中,ETEC标准样品加入20种食品基质后均可检出,而本底对照均未检出。结论 本实验制备的... 相似文献