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61.
In this paper, we present a branch-and-bound approach for solving a two-machine flow shop scheduling problem, in which the objective is to minimize a weighted combination of job flowtime and schedule makespan. Experimental results show that the algorithm works very well for certain special cases and moderately well for others. In fact, it is able to produce optimal schedules for 500-job problems in which the second machine dominates the first machine. It is also shown that the algorithm developed to provide an upper bound for the branch-and-bound is optimal when processing times for jobs are the same on both machines. The primary reason for developing the branch-and-bound approach is that its results can be used to guide other heuristic techniques, such as simulated annealing, tabu search and genetic algorithms, in their search for optimal solutions for larger problems.  相似文献   
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An efficient single step process for the construction of pharmaceutically relevant substituted aminobenzoxazoles have been described in this report. Various electrodes and electrolytes combinations have been carried out to harvest optimum coupling results. The presented CN bond formation reaction methodology has applied for the synthesis of biologically active compounds. This methodology saves reaction steps over traditional functionalization reactions.  相似文献   
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Let P = {1, 2, . . . , n} be a set of elements called participants. In this paper we construct a visual cryptography scheme (VCS) for the strong access structure specified by the set Γ0 of all minimal qualified sets, where ${\Gamma_0=\{S: S\subseteq P, 1\in S}$ and |S| = k}. Any VCS for this strong access structure is called a (k, n)*-VCS. We also obtain bounds for the optimal pixel expansion and optimal relative contrast for a (k, n)*-VCS.  相似文献   
66.
Films of nanocrystalline γ-Fe2O3 were deposited on silicon substrates by using the technique of electrophoretic deposition. The precursor powder was nanocrystalline γ-Fe2O3, which was synthesized, using DC arc plasma in the oxygen ambient by vapour–vapour interaction in gas phase condensation; at a stabilized arc current of 40 A. This powder was characterized by X-ray diffraction, Transmission Electron Microscopy, Vibrating Sample Magnetometer and Mössbauer Spectroscopy. An increase in directional coercivity was observed in case of films deposited on silicon substrates, which is dramatically significant. Preferred orientation of almost similar sized nanocrystalline magnetic domains in deposited films is evident from the results of X-ray diffraction and Transmission Electron Microscopy results. The preferred alignment of the nanocrystallites seems to be responsible for the significant changes observed in magnetic properties of films.  相似文献   
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Non-aqueous reactions of aluminum isopropoxide with 8-hydroxyquinoline (Hq = HONH6C9) in 1:1, 1:2 and 1:3 molar ratios in anhydrous benzene yield complexes of the type [qnAl(OPri)3?n] {where n = 1 (1), n = 2 (2), n = 3 (3)}. Progress of the reactions were monitored by estimating liberated 2-propanol in benzene-2-propanol azeotrope by oxidimetric method. All the products were fluorescent green powders, sparingly soluble in CHCl3. They were characterized by elemental analysis, FT-IR and (1H, 13C and 27Al) NMR studies. The ESI mass spectral studies indicate dimeric nature for (1) and (2) and monomeric nature for the compound (3). The XRD spectra of (13) showed crystalline nature with the average particle size of 45, 32 and 27 nm respectively, as evaluated from DebyeScherrer equation. The XRD spectrum of (3) also suggests the formation of β-crystalline polymorphs of Alq3. The SEM images appear to indicate granular morphology for (1) and formation of cylindrical shaped rods for (2) and (3). Sol–gel hydrolysis of (1), (2) or (3) in presence of a strong acid as well as of the precursor, Al(OPri)3,without acid or base catalyst, followed by sintering at 950 °C yielded tetragonal primitive phase of nano-sized δ-alumina in all the cases, as reflected by their powder X-ray diffraction pattern. The IR, SEM and EDX studies also support the formation of transition alumina.  相似文献   
69.
Designs, Codes and Cryptography - Given $$m, n, qin mathbb {N}$$ such that q is a prime power and $$mge 3$$ , $$ain mathbb {F}_q$$ , we establish a sufficient condition for the existence of a...  相似文献   
70.
The role of inflammation in cancer generation is gaining importance in the field of cancer research. The chemo‐anti‐inflammatory strategy that involves using non‐steroidal anti‐inflammatory drug compounds as effective anti‐tumor agents is being acceded globally. In the present study, seven new Pt (IV) complexes based on cisplatin, carboplatin and oxaliplatin scaffold bearing the anti‐inflammatory drug naproxen in the axial position were synthesized and characterized by elemental analysis, ESI‐MS, Fourier transform‐infrared, 1H‐ and 195Pt‐NMR spectroscopy. The reduction behavior in the presence of ascorbic acid was studied using high‐performance liquid chromatography. The cytotoxicity against two human breast cell lines and the anti‐inflammatory properties were evaluated. All the complexes are able to promote a comparable activity, with average three‐ and 13‐fold more cytotoxic than cisplatin against MCF7 and MDA‐MB‐231 cell lines, respectively. The complexes show remarkable anti‐inflammatory effects, which indicated their potential in treating cancer associated with inflammation and reducing side‐effects of chemotherapy.  相似文献   
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