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1.
Harish C. Bahl Stanley Zionts 《The Journal of the Operational Research Society》1987,38(12):1141-1148
Scheduling the production of several items requires the determination of production quantities in different periods in the presence of resource constraints. Several approximate and heuristic algorithms have been proposed to solve this problem. However, no method for finding an optimal solution has as yet been developed. It is shown that the problem may be solved advantageously using Benders' decomposition. The subproblem in Benders' decomposition is shown to be a transportation problem, and some strategies for solving the master problem are indicated. The paper concludes with a sample problem demonstrating the application of the method. 相似文献
2.
Przemyslaw Bogacki Stanley Weinstein Yuesheng Xu 《Advances in Computational Mathematics》1997,7(4):593-621
We consider the choice of a functional to measure the distance between two parametric curves. We identify properties of such
a distance functional that are important for geometric design. Several popular definitions of distance are examined, and new
functionals are presented which satisfy the desired properties.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
A family of infinite measure preserving odometers is presented which exhibit examples ofp-recurrent but notp+1-recurrent ergodic transformations for everyp>1. 相似文献
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D. Ohlberg J.J. Blackstock R. Ragan S. Kim R. Stanley Williams 《Applied Physics A: Materials Science & Processing》2005,80(6):1327-1334
A recently demonstrated [1] in-vacuo template-stripping process is applied to the study of platinum films stripped from ultra-flat silicon-oxide surfaces. Template-stripped (TS) Pt surfaces, prepared with a range of post-deposition annealing times prior to being stripped from the templating surface in an ultra-high vacuum (UHV) environment, are examined by UHV scanning tunneling microscopy (STM). These studies reveal that without post-deposition annealing, TS Pt surfaces are largely made up of poorly-ordered, granular nanostructures undesirable for many applications. The post-deposition annealing treatments explored in the study result in the emergence and continuous growth of large smooth crystallites. Issues with crystallite orientation relative to the TS surface and artefacts arising as a result of the epoxy used in the template-stripping process are presented and discussed in relation to optimizing the template-stripping procedure for specific applications such as self-assembled monolayer (SAM) formation for molecular electronics. PACS 68.37.Ef; 68.47.De; 68.55.Jk; 81.05.Bx; 81.15.Ef 相似文献
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Richard P. Stanley 《Israel Journal of Mathematics》2004,143(1):317-339
We survey three recent developments in algebraic combinatorics. The first is the theory of cluster algebras and the Laurent
phenomenon of Sergey Fomin and Andrei Zelevinsky. The second is the construction of toric Schur functions and their application
to computing three-point Gromov-Witten invariants, by Alexander Postnikov. The third development is the construction of intersection
cohomology for nonrational fans by Paul Bressler and Valery Lunts and its application by Kalle Karu to the torich-vector of a nonrational polytope. We also briefly discuss the “half hard Lefschetz theorem” of Ed Swartz and its application
to matroid complexes.
Partially supported by NSF grant #DMS-9988459. 相似文献
8.
Stanley D. Rasberry 《Fresenius' Journal of Analytical Chemistry》1993,345(2-4):87-89
Summary Sales and use of analytical instruments have expanded in the United States over the past two years, despite the recessionary nature of the economy. Interest in increasing the quality of analytical measurements seems to be undiminished, if not growing. Trends in several measurement areas, including health, environment, manufacturing, and commerce, are described as they bear on this growth of interest in reliably accurate measurements. The paper also considers trends in the development of reference materials and accreditation of laboratories in the USA. United States of America participation in efforts of the International Organization for Standardization, and a study by the International Bureau of Weights and Measures of how to provide for international traceability for analytical chemical measurements are mentioned. 相似文献
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