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71.
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73.
Wai Kuan Foong Angus R. Simpson Holger R. Maier Stephen Stolp 《Annals of Operations Research》2008,159(1):433-450
A number of algorithms have been developed for the optimization of power plant maintenance schedules. However, the true test
of such algorithms occurs when they are applied to real systems. In this paper, the application of an Ant Colony Optimization
formulation to a hydropower system is presented. The formulation is found to be effective in handling various constraints
commonly encountered in practice. Overall, the results obtained using the ACO formulation are better than those given by traditional
methods using engineering judgment, which indicates the potential of ACO in solving realistic power plant maintenance scheduling
problems. 相似文献
74.
Let V be an indefinite quadratic space over a number field F and U be a nondegenerate subspace of V. Suppose that M is a lattice on V, and that N is a lattice on U which is represented by M locally everywhere. The main result of this paper is a necessary and sufficient condition for which there exists a representation of N by M that approximates a given family of local representations. This is applied to determine when the variety of representations of U by V has strong approximation with respect to a finite set of primes of F that contains all the archimedean primes. 相似文献
75.
Lap Mou Tam Juhn Horng Chen Hsien Keng Chen Wai Meng Si Tou 《Chaos, solitons, and fractals》2008,38(3):826-839
A system with more than one positive Lyapunov exponent can be classified as a hyperchaotic system. In this study, a sinusoidal perturbation was designed for generating hyperchaos from the Chen–Lee chaotic system. The hyperchaos was identified by the existence of two positive Lyapunov exponents and bifurcation diagrams. The system is hyperchaotic in several different regions of the parameters c, ε, and ω. It was found that this method not only can enhance or suppress chaotic behavior, but also induces chaos in non-chaotic parameter ranges. In addition, two interesting dynamical behaviors, Hopf bifurcation and intermittency, were also found in this study. 相似文献
76.
Li Liu Ling‐Xiang Qiao Shi‐Zhong Liu Dong‐Mei Cui Chun‐Mei Zhang Zheng‐Ji Zhou Zu‐Liang Du Wai‐Yeung Wong 《Journal of polymer science. Part A, Polymer chemistry》2008,46(10):3193-3206
A new family of organometallic/inorganic composite Langmuir‐Blodgett (LB) films consisting of rigid‐rod polyplatinayne polymer ([Pt‐T(OMe‐Fl)T]∞ or [Pt‐T(F‐Fl)T]∞, where the triplet bonds are abbreviated by T, and fluorene ring by Fl) as the π‐conjugated organometallic molecule, polyoxometalate (POM, POM = K3PMo12O40, H3PW12O40, or H6P2W18O62) of the Keggin and Dawson structures as the inorganic component, and dimethyldioctadecylammonium bromide (DODA) or a mixture of octadecanoic acid (OA) and docosanoic acid (DA) as the auxiliary film‐forming agent were prepared and characterized by π–A isotherms, UV–Vis absorption spectra, photoluminescence spectra, atomic force microscopy imaging, scanning tunneling microscopy, and low‐angle X‐ray diffraction. Our experimental results indicate that steady, even, and ordered Langmuir and LB films are formed in pure water and polyoxometalate subphases. It was shown that the POM molecules are probably embedded inside the polyplatinayne molecules in the LB film structure and they can quench the luminescence of the Pt polyyne. These Pt‐polyyne based LB films display interesting electric conductivity behavior. [Pt‐T(OMe‐Fl)T]∞/DODA/HPW12 monolayer film shows a good electrical conductivity, and the tunneling current amounts to ±100 nA when the voltage is set at ±8 V. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3193–3206, 2008 相似文献
77.
V. M. Murukeshan Ng Chee Keong Krishnakumar. V Ong Lin Seng A. Asundi 《Optics & Laser Technology》2001,33(5):919
This paper presents a double shearographic configuration based on the optical method by using two Michelson interferometers in tandem. The problems associated with the extraction of second order derivatives by optical means and a comparison with the proposed novel approach by digital means are discussed in this paper. 相似文献
78.
THE ANALYTICAL SOLUTION FOR SEDIMENT REACTION AND DIFFUSION EQUATION WITH GENERALIZED INITIAL-BOUNDARY CONDITIONS 总被引:1,自引:0,他引:1
1 TheGeneralizedInitialandBoundaryProblemforSedimentTransportIntheresearchofnonequilibriumsedimenttransportwithreactionanddiffusionconditions,weneedtoconsiderthefollowingequation c t=w c z k 2 c z2 rc,(1 )andtheinitialvalueaswellasthegeneralizedboundarycondit… 相似文献
79.
Granzyme-mediated apoptosis, supported by pore-forming perforin, plays an important role in CD8+ T lymphocytes (CTL)-dependent cellular immunity protection against both cancer and viral infection. Quantitative and qualitative problems with CTL are potential contributing factors to disease progression. The feasibility of developing CTL-independent cellular immunity is desired but must first overcome the barrier of CTL-independent target cell recognition. Granzyme B with its strong pro-apoptotic activity in many different target cells is investigated for use in the CTL-independent cellular immunity approach, and granzyme B or its bioactive peptides without the enzymatic activity are more desirable for use. Native granzyme B with enzymatic activity is usually investigated in cancer cells for its mediation of apoptosis by detection of DNA fragmentation. Detection of cell death mediated by such peptides in cancer cells is needed to demonstrate the potential therapeutic purposes. We show with never-before-seen microscopic images using fluorescence microscopy that a synthetic granzyme B-like peptide fluorescent conjugate (GP1R) can: 1) mediate cell death of different cancer cells via membrane extrusion, 2) bind to constitutively expressed binding targets in different cancer cells and bacteria, and 3) promote bacterial phagocytosis. The putative binding targets may serve as a universal pathologic biomarker detectable by GP1R. Our data taken together demonstrate the potential applications of GP1R for use in CTL-independent target cell recognition and target cell death induction. It may lead to development of rapid targeted detection and new treatment of cancer, viral and bacterial infections. The new treatment may show mutual benefits for two or more diseases. 相似文献
80.
Preparation of the enantiomeric pair of 3‐[2‐(3‐benzenesulfonylamino‐7‐oxabicyclo[2.2.1]hept‐2‐yl‐methyl)phenyl] propionic acid, a novel thromboxane antagonist is reported. They are synthesized from either enantiomers of known (1R,2R,3R,4S)‐3‐[2‐(3‐carboxy‐7‐oxabicyclo[2,2,1]hept‐2‐yl‐methyl)phenyl]‐propionic acid methyl ester via epimerization, modified Curtius' rearrangement and sulfonylamino formation. Other derivatives may be prepared similarly. 相似文献