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81.
In this paper we propose a framework for dynamic routing systems based on their degree of dynamism. Next, we consider its impact on solution methodology and quality. Specifically, we introduce the Partially Dynamic Travelling Repairman Problem and describe several dynamic policies to minimize routing costs. The results of our computational study indicate that increasing the dynamic level results in a linear increase in route length for all policies studied. Furthermore, a Nearest Neighbour policy performed, on the average, uniformly better than the other dispatching rules studied. Among these, a Partitioning policy produced only slightly higher average route lengths. 相似文献
82.
A family of Hecke C*-algebras can be realised as crossed productsby semigroups of endomorphisms. It is shown by dilating representationsof the semigroup crossed product that the category of representationsof the Hecke algebra is equivalent to the category of continuousunitary representations of a totally disconnected locally compactgroup. 相似文献
83.
Li W Nelson DP Jensen MS Hoerrner RS Cai D Larsen RD Reider PJ 《The Journal of organic chemistry》2002,67(15):5394-5397
3-Pyridylboronic acid was prepared in high yield and bulk quantity from 3-bromopyridine via a protocol of lithium-halogen exchange and "in situ quench". This technique was further studied and evaluated on other aryl halides in the preparation of arylboronic acids. 相似文献
84.
Jack B. Brown Udayan B. Darji Eric P. Larsen 《Proceedings of the American Mathematical Society》1999,127(1):173-182
We investigate the relationships between the notions of a continuous function being monotone on no interval, monotone at no point, of monotonic type on no interval, and of monotonic type at no point. In particular, we characterize the set of all points at which a function that has one of the weaker properties fails to have one of the stronger properties. A theorem of Garg about level sets of continuous, nowhere monotone functions is strengthened by placing control on the location in the domain where the level sets are large. It is shown that every continuous function that is of monotonic type on no interval has large intersection with every function in some second category set in each of the spaces , and .
85.
Christian L. Pedersen Ole Buchardt Sine Larsen Kenneth J. Watson 《Tetrahedron letters》1973,14(24):2195-2198
86.
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88.
N.R. Zangenberg A. Nylandsted Larsen 《Applied Physics A: Materials Science & Processing》2005,80(5):1081-1086
Vacancy-related defects in Si are explored with deep level transient spectroscopy (DLTS). The measurements are performed on-line on irradiated p-type Si and a new trap with the signature (Epa, pa) = (0.18 eV, 6.5×10-15 cm2) – only present at cryogenic temperatures – is studied. Furthermore, the bi-stable boron-vacancy complex is studied and its configuration at low temperatures is investigated and found to have the signature (Epa, pa) = (0.11 eV, 8.2×10-15 cm2). PACS 71.55.Cn; 61.80.Fe; 61.82.Fk; 61.72.Ji 相似文献
89.
[chemical reaction: see text]. Prior to detachment of compounds synthesized on sulfonamide based safety-catch linkers, the molecular anchor has to be activated. This is achieved by alkylation of the nitrogen atom of the N-acylsulfonamide using different established protocols. As an addition to the existing repertoire of activating reagents, we suggest the use of O,N,N'-trialkylisoureas. Besides the demonstration of the feasibility of these mild alkylating agents for this purpose, custom-tailored novel O,N,N'-trialkylisoureas prepared from electron-deficient alcohols are reported. 相似文献
90.