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1.
In this note we show that many classes of global optimization problems can be treated most satisfactorily by classical optimization theory and conventional algorithms. We focus on the class of problems involving the minimization of the product of several convex functions on a convex set which was studied recently by Kunoet al. [3]. It is shown that these problems are typical composite concave programming problems and thus can be handled elegantly by c-programming [4]–[8] and its techniques.  相似文献   
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The design of tunable large angular aperture TeO2 noncollinear acousto-optic filters for use in the 1.0–1.6m region is discussed. It is shown that it is possible to maximize the angular aperture of such a filter by the correct choice of the direction for the acoustic wave vector and that this required direction is independent of the operating wavelength in the range 1.0–1.6m. The theoretical model adopted is verified by comparison with experimentally measured filter characteristics and the design of filters with narrow bandwidths and low power requirements is discussed.  相似文献   
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In the present study we examine the thermodynamics of binding of two related pyrazine-derived ligands to the major urinary protein, MUP-I, using a combination of isothermal titration calorimetry (ITC), X-ray crystallography, and NMR backbone (15)N and methyl side-chain (2)H relaxation measurements. Global thermodynamics data derived from ITC indicate that binding is driven by favorable enthalpic contributions, rather than the classical entropy-driven hydrophobic effect. Unfavorable entropic contributions from the protein backbone and side-chain residues in the vicinity of the binding pocket are partially offset by favorable entropic contributions at adjacent positions, suggesting a "conformational relay" mechanism whereby increased rigidity of residues on ligand binding are accompanied by increased conformational freedom of side chains in adjacent positions. The principal driving force governing ligand affinity and specificity can be attributed to solvent-driven enthalpic effects from desolvation of the protein binding pocket.  相似文献   
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Self‐assembled metallosupramolecular architectures (MSAs) with built‐in functionalities such as light‐harvesting metal centers are a promising approach for developing emergent properties within discrete molecular systems. Herein we describe the synthesis of two new but simple “click” ligands featuring a bidentate 2‐pyridyl‐1,2,3‐triazole chelate pocket linked to a monodentate pyridyl (either 3‐ or 4‐substituted, L1 and L2 ) unit. The ligands and the corresponding four PdIIand PtIImetallo‐ligands ( Pd1 , Pd2 , Pt1 and Pt2 ) were synthesized and characterized using nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry (ESI‐MS), and X‐ray crystallography. Solid‐state characterization of the series of ligands and metallo‐ligands revealed that these compounds display a co‐planar conformation of all the aryl units. The PtIIcontaining metallo‐ligands ( Pt1 and Pt2 ) were found to assemble into square ( Sqr ) and triangular ( Tri ) shaped architectures when combined with neutral PdCl2 linker units. Additionally, the ability of the PtIImetallo‐ligands and Tri to photocatalyze the cycloaddition of singlet oxygen to anthracene was investigated.  相似文献   
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Measurements of synchrotron radiation emitted by 30-MeV runaway electrons in the TEXTOR-94 tokamak show that the runaway population decays after switching on neutral beam injection (NBI). The decay starts only with a significant delay, which decreases with increasing NBI heating power. This delay provides direct evidence of the energy dependence of runaway confinement, which is expected if magnetic modes govern the loss of runaways. Application of the theory by Mynick and Strachan [Phys. Fluids 24, 695 (1981)] yields estimates for the "mode width" (delta) of magnetic perturbations: delta<0.5 cm in Ohmic discharges, increasing to delta = 4.4 cm for 0. 6 MW NBI.  相似文献   
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A series of star-shaped oligofluorene molecules, each containing a TPE core, have been specifically designed and produced to show effective aggregation-induced emission (AIE). Each molecule differs either in the number of fluorene units within the arms (e.g., 1 or 4, compounds 4 and 5 ), or the terminal group positioned at the end of each arm (e.g., H, TMS, or TPA, compounds 4 , 6 , and 7 ). Although they are all poor emitters in solution phase they become efficient yellow-green luminogens in the condensed state. Their AIE properties were investigated in THF/H2O mixtures, with each molecule exhibiting a clear emission enhancement at specific water contents. An all-organic distributed feedback (DFB) laser was fabricated using compound 4 as the gain material and exhibited an average threshold energy fluence of 60 ± 6 μJ/cm2 and emission in the green region. Furthermore, piezofluorochromism studies on a thin film of this material displayed a linear dependence of the amplified spontaneous emission (ASE) peak position on applied pressure, indicating potential applications as lasing-based pressure sensors. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 734–746  相似文献   
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This paper discusses the question of how operational research in general, and discrete event simulation in particular, can help to meet management challenges in hospital-based orthopaedics medicine. It focuses on the reduction of waiting times for elective patients, both for a first outpatient appointment and for the subsequent commencement of in-patient treatment. The research is based on a series of projects carried out by students from the Department of Management Science, University Strathclyde in Stobhill Hospital and the Glasgow Royal Infirmary between 1999 and 2003. An increasingly detailed and complex simulation model was developed for the musculo-skeletal service provided by these hospitals. The paper discusses the application of a modelling methodology—based on the idea of requisite models evolving over time—that is participatory, iterative and focused on enhancing the clients' understanding of the main performance drivers of the service. It concludes that this methodology fits well with successful strategies to sustain reductions in waiting times.  相似文献   
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