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111.
We propose using support vector machines (SVMs) to learn the efficient set in multiple objective discrete optimization (MODO). We conjecture that a surface generated by SVM could provide a good approximation of the efficient set. As one way of testing this idea, we embed the SVM-approximated efficient set information into a Genetic Algorithm (GA). This is accomplished by using a SVM-based fitness function that guides the GA search. We implement our SVM-guided GA on the multiple objective knapsack and assignment problems. We observe that using SVM improves the performance of the GA compared to a benchmark distance based fitness function and may provide competitive results.  相似文献   
112.
In this letter, we report on the use of tin as an effective surfactant material for silver growing on silicon oxide. We observed that submonolayers of Sn pre-deposited on SiO2 result in earlier film coalescence and formation of smoother Ag layers. We suggest that Sn atoms reduce the Ag-adatom mobility resulting in experimentally observed increased island density and decreased film roughness. Angle-resolved X-ray photoelectron spectroscopy reveals that Sn remains under the Ag layer giving circumstantial evidence that at later stages of Ag film growth Sn does not influence the interlayer transport.  相似文献   
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The lifting scheme has been found to be a flexible method for constructing scalar wavelets with desirable properties. Here it is extended to the construction of multiwavelets. It is shown that any set of compactly supported biorthogonal multiwavelets can be obtained from the Lazy matrix filters with a finite number of lifting steps. As an illustration of the general theory, compactly supported biorthogonal multiwavelets with optimum time–frequency resolution are constructed. In addition, experimental results of applying these multiwavelets to image compression are presented.  相似文献   
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116.

Background

The aim of the current work was to determine thermo dynamical properties of 5(2-nitro phenyl)-furan-2-carbaldehyde, 5(3-nitro phenyl)-furan-2-carbaldehyde and 5(4-nitro phenyl)-furan-2-carbaldehyde.

Results

The temperature dependence of saturated vapor pressure of 5(2-nitro phenyl)-furan-2-carbaldehyde, 5(3-nitro phenyl)-furan-2-carbaldehyde and 5(4-nitro phenyl)-furan-2-carbaldehyde was determined by Knudsen’s effusion method. The results are presented by the Clapeyron–Clausius equation in linear form, and via this form, the standard enthalpies, entropies and Gibbs energies of sublimation and evaporation of compounds were calculated at 298.15 K. The standard molar formation enthalpies of compounds in crystalline state at 298.15 K were determined indirectly by the corresponding standard molar combustion enthalpy, obtained using bomb calorimetry combustion.

Conclusions

Determination of the thermodynamic properties for these compounds may contribute to solving practical problems pertaining optimization processes of their synthesis, purification and application and it will also provide a more thorough insight regarding the theoretical knowledge of their nature.
Graphical abstract: Generalized structural formula of investigated compounds and their formation enthalpy determination scheme in the gaseous state
  相似文献   
117.
We investigate the problem of finding the nadir point for multiobjective discrete optimization problems (MODO). The nadir point is constructed from the worst objective values over the efficient set of a multiobjective optimization problem. We present a new algorithm to compute nadir values for MODO with \(p\) objective functions. The proposed algorithm is based on an exhaustive search of the \((p-2)\)-dimensional space for each component of the nadir point. We compare our algorithm with two earlier studies from the literature. We give numerical results for all algorithms on multiobjective knapsack, assignment and integer linear programming problems. Our algorithm is able to obtain the nadir point for relatively large problem instances with up to five-objectives.  相似文献   
118.
It has been previously observed that the measured frequency of ions in a Fourier transform mass spectrometry experiment depend upon the number of trapped ions, even for populations consisting exclusively of a single mass-to-charge. Since ions of the same mass-to-charge are thought not to exert a space-charge effect among themselves, the experimental observation of such frequency shifts raises questions about their origin. To determine the source of such experimentally observed frequency shifts, multiparticle ion trajectory simulations have been conducted on monoisotopic populations of Cs+ ranging from 102 ions to 106 ions. A close match to experimental behavior is observed. By probing the effect of ion number and orbital radius on the shift in the cyclotron frequency, it is shown that for a monoisotopic population of ions, the frequency shift is caused by the interaction of ions with their image-charge. The addition of ions of a second mass-to-charge to the simulation allows the comparison of the magnitude of the frequency shift resulting from space-charge (ion-ion) effects versus ion interactions with their image charge.  相似文献   
119.
Three‐dimensional mesoscopic morphologies and the thermodynamics of structural phase transitions of amphiphilic lipids at air‐water interfaces are studied using self‐consistent field theory. Changing the relative amount of lipids in the system led to a series of 3D morphologic phases with varying average interfacial area per molecule, mimicking a compression of the model membranes. Membranes of both saturated and unsaturated lipids undergo a transition from cylindrical micelle to lamella when the lipid content in the system increases from 2% to about 19–20%. With further increase in the lipid content, saturated lipids first develop non‐uniform quasi‐2D distributions in the lamella and then gradually transform into a hybrid morphology containing quasi‐planar lamellae. In contrast, unsaturated lipids develop reverse‐micellar morphologies.

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120.
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