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411.
This paper presents a co-evolutionary particle swarm optimization (PSO) algorithm, hybridized with noising metaheuristics,
for solving the delay constrained least cost (DCLC) path problem, i.e., shortest-path problem with a delay constraint on the
total “cost” of the optimal path. The proposed algorithm uses the principle of Lagrange relaxation based aggregated cost.
It essentially consists of two concurrent PSOs for solving the resulting minimization-maximization problem. The main PSO is
designed as a hybrid PSO-noising metaheuristics algorithm for efficient global search to solve the minimization part of the
DCLC-Lagrangian relaxation by finding multiple shortest paths between a source-destination pair. The auxiliary/second PSO
is a co-evolutionary PSO to obtain the optimal Lagrangian multiplier for solving the maximization part of the Lagrangian relaxation
problem. For the main PSO, a novel heuristics-based path encoding/decoding scheme has been devised for representation of network
paths as particles. The simulation results on several networks with random topologies illustrate the efficiency of the proposed
hybrid algorithm for the constrained shortest path computation problems. 相似文献
412.
We present a direct method for finding particular solutions of equations of sine-Gordon type, including single sinh-Gordon equation, single sine-Gordon equation, double sinh-Gordon and double sine-Gordon equations. 相似文献
413.
414.
V. I. Kelarev M. Bellul' R. A. Karakhanov Dibi Ammar A. F. Lunin 《Chemistry of Heterocyclic Compounds》1987,23(3):298-304
The reaction of 2-amino- and 2,4-diamino-sym-triazines with nitrourea and phenyl isocyanate was studied; it gives N-mono- and N,N-disubstituted ureas that contain sym-triazine segments. General features were established for the decomposition of carbamide derivatives of sym-triazine under electron impact.For communication 4, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 356–362, March, 1987. 相似文献
415.
Effect of the server capacity distribution on the optimal control of a bulk service queueing system 总被引:1,自引:0,他引:1
In this paper the optimal control of a single-channel bulk service queueing system with random server capacity is investigated. Given an accumulation level r, the server stops processing new customers whenever the queue falls below r and resumes service when the queue reaches level r again. Server capacity becomes random following an idle period. A quick search procedure is designed to determine the value of r that yields the minimum expected total cost per unit of time. The effect of the server capacity distribution on the optimal control is then studied. Finally, a sensitivity analysis is conducted in order to assess the extent to which our results are valid. 相似文献
416.
B. M. Moharram A. M. El-Khatib E. A. Ammar 《Isotopes in environmental and health studies》2013,49(10):461-463
Thicknesses of gold and silver thin films have been determined by NAA technique. Reasonable agreement with conventional optical method has been obtained, but the lower detection limit in the case of NAA is far better than in the optical method. Es wurde die Dicke von Gold- und Silberfilmen mittels NAA-Technik bestimmt. Dabei konnte eine vernünftige Übereinstimmung mit der konventionellen optischen Methode erzielt werden, wobei im Falle der NAA die untere Nachweis grenze wescntlich besser war als vergleichsweise die optische Methode. 相似文献
417.
This paper explores the relations between the matrix Riccati equation and the standard matrix eigenvalue methods. It is demonstrated that the mathematics of the analysis of the two objects is essentially the same; consisting of the analysis of flows on the homogeneous spaces of various Lie groups.Supported in part by DOE Contract DE-ACOL-80RA-5256.Supported in part by DOE Contract DE-ACOL-80RA-5256 and by NASA Grant DAG2-82. 相似文献
418.
Pozzar F Sassi A Pace G Lora S D'Archivio AA Jeràbek K Grassi A Corain B 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(24):7395-7404
Six gel-type functional resins, that is, three poly-DMAA-co-TMPTP (DMAA = N,N-dimethylacrylamide, TMPTP = trimethylolpropyltrimethacrylate) samples with different degrees of cross-linking (0.6, 1.2, 1.7 % mol) and three poly-DMAA-co-MA-co-TMPTP (MA = methacrylic acid, ca. 5.5 % mol) samples with 1.7, 3.5, and 7 % mol cross-linking were investigated with ISEC (inverse steric exclusion chromatography), and ESR and CP-MAS (cross polarization magic angle spinning) 13C NMR spectroscopy after swelling in water and other solvents. This unprecedented combination of conceptually independent physicochemical techniques provides a thorough overall consistent picture of the morphology of the resins on the nanometer scale and of the molecular accessibility of the swollen polymer framework to the paramagnetic probe TEMPONE (2,2,6,6-tetramethyl-4-oxo-1-oxypiperidine) and to selected solvents. 相似文献
419.
A. Godone E. Bava M. P. Sassi F. Bertinetto P. Cordiale 《International Journal of Infrared and Millimeter Waves》1986,7(2):293-298
The absorptions of RuO4 coincident with12C16O2 and14N2
16O laser lines have been observed with sub-Doppler resolution and their frequency distances from the laser line-centers have been measured. These preliminary results suggest a possible extension of the absolute reference frequency grid up to the 10.9 m region, based on transitions of hyperfine-structure free heavy molecules. 相似文献
420.
Alexander J Artuso M Bebek C Berkelman K Cassel DG Cheu E Coffman DM Crawford G DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Katayama N Kreinick DL Lewis JD Mistry NB Mueller J Namjoshi R Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Silverman A Stone S Worden H Worris M Sadoff AJ Avery P Besson D Garren L Yelton J Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Ammar R Baringer P Coppage D 《Physical review letters》1990,64(19):2226-2229