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761.
Solving Location-allocation Problems with Rectilinear Distances by Simulated Annealing 总被引:1,自引:0,他引:1
Chih-Ming Liu Ruey-Li Kao An-Hsiang Wang 《The Journal of the Operational Research Society》1994,45(11):1304-1315
The objective of this study is to use the simulated annealing method to solve minisum location-allocation problems with rectilinear distances. The major advantage of the simulated annealing method is that it is a very general and efficient algorithm for solving combinatorial optimization problems with know objective functions. In this study, a simulated annealing algorithm was developed to solve the location-allocation problems, and its performance was compared with two other popular methods for solving location-allocation problems. The results show that simulated annealing is a good alternative to the two methods, as measured by both the solution quality and the computational time. 相似文献
762.
The conformational characteristics of allylamine were investigated by the ab initio STO -3G basis set. The results indicate that the molecule exists in a number of stable conformations through rotations about the CC? NH and CC? CN bonds. The TE (trans-CCNLP , LP representing lone-pair electrons, and eclipsed-CCCH) is the most stable, while TC (trans-CCNLP and cis-CCCN), GE (gauche-CCNLP and eclipsed-CCCH), G′C(gauche′-CCNLP and cis-CCCN), and G′E (gauche′-CCNLP and eclipsed-CCCH) conformations are less stable, respectively, by 0.41, 0.67, 0.92, and 1.14 kcal mol?1. These results are in general consistent with previous experimental results. Rationale for the conformational characteristics and order of stabilities are explored. 相似文献
763.
A nonplanar, reentrant two-spherical-mirror ring cavity is demonstrated. It is compact and free of astigmatism. Unidirectional operation is achieved by use of reciprocal and nonreciprocal polarization rotators to differentiate round-trip loss. A single-frequency green laser is generated by intracavity frequency doubling. Amplitude noise as low as 0.25% is achieved. 相似文献
764.
J.-M.L. Beaujour W. Chen K. Krycka C.-C. Kao J. Z. Sun A. D. Kent 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,59(4):475-483
We report on room temperature
ferromagnetic resonance (FMR) studies of [ t Co|2t Ni] × N
sputtered films, where 0.1 ≤ t ≤ 0.6 nm. Two series of
films were investigated: films with the same number of Co|Ni bilayer
repeats (N = 12), and samples in which the overall magnetic layer
thickness is kept constant at 3.6 nm (N = 1.2/t). The FMR
measurements were conducted with a high frequency broadband
coplanar waveguide up to 50 GHz using a flip-chip method. The
resonance field and the full width at half maximum were measured
as a function of frequency for the field in-plane and field normal
to the plane, and as a function of angle to the plane for several
frequencies. For both sets of films, we find evidence for the
presence of first and second order anisotropy constants, K1 and
K2. The anisotropy constants are strongly dependent on the
thickness t, and to a lesser extent on the total thickness of
the magnetic multilayer. The Landé g-factor increases with
decreasing t and is practically independent of the multilayer
thickness. The magnetic damping parameter α, estimated from
the linear dependence of the linewidth ΔH, on
frequency, in the field in-plane geometry, increases with
decreasing t. This behaviour is attributed to an enhancement of
spin-orbit interactions with decreasing Co layer thickness and in thinner films,
to a spin-pumping contribution to the damping. 相似文献
765.
Re-Ching Lin Ying-Chung Chen Kuo-Sheng Kao 《Applied Physics A: Materials Science & Processing》2007,89(2):475-479
This study investigates high-performance ZnO piezoelectric films used for thin film bulk acoustic resonators (TFBAR). The
ZnO piezoelectric film was deposited on a Pt/Ti electrode using an RF magnetron sputter by a two-step method at room temperature.
The Pt/Ti electrode was deposited by a DC sputtering system, on which, ZnO piezoelectric films were deposited in one step
and in two steps to minimize roughness in the first step and produce the preferred orientation in the second. Both field-emission
scanning electron microscopy (FESEM) and atom force microscopy (AFM) revealed that ZnO piezoelectric film deposited by two-step
sputtering exhibited favorable characteristics, such as a rigidly precise surface structure with surface roughness of 7.37 nm,
even better than in one-step sputtering. Examining the ZnO thin film by X-ray diffraction (XRD) showed a much higher c-axis-preferring
orientation than in one-step sputtering. The reflection coefficient of the resonator device was measured using an HP8720 network
analyzer. The frequency response of the FBAR device exhibited a return loss of -25 dB at a resonant frequency of 2212 MHz
with a high coupling coefficient of 6.7%.
PACS 68.55.Jk; 43.35.Ns; 81.15.-z 相似文献
766.
Chi-Hua Tung Yen-Ta Lu Wei-Ting Kao Jen-Wei Liu Yi-Hsuan Lai Shinn-Jong Jiang Hao-Ping Chen Tzenge-Lien Shih 《中国化学会会志》2020,67(7):1254-1262
Three novel naphthalimide-based derivatives were synthesized and tested in vitro as anticancer agents. Our previous report of the C4-benzazole 1,8-naphthalimide derivatives showed good inhibition against murine melanoma. We aimed to synthesize more potent agents and found that compound 5 reported in this article behaved 5- to 10-fold potency than our previous best results. The unique structure of compound 5 consisted of a naphthalimide framework in which C4 position was linked with an ethylenediamine group where the amino group was coupled with a 2-piconic acid moiety. Compound 5 exhibited the most potent inhibitory activity toward human DNA topoisomerase II proteins with IC50 value (2.6 ± 0.1 μM) against murine B16F10 melanoma cells among the three target compounds synthesized in this study. In accordance with this finding, the results of molecular docking also revealed that compound 5 has the highest affinity with human DNA topoisomerase II among the selected compounds. Compound 5 , therefore, has high potential for becoming a lead compound. 相似文献
767.
Two novel indium silicates, K5In3Si7O21 (1) and K4In2Si8O21 (2), have been synthesized by a flux-growth method and characterized by single-crystal X-ray diffraction. The structure of 1 consists of siebener single chains of corner-sharing SiO4 tetrahedra running along the b axis linked via corner-sharing by In2O9 face-sharing octahedral dimers and InO5 trigonal bipyramids to form a 3D framework. The structure of 2 consists of a 3D silicate framework containing 6- and 14-ring channels. InO5 square pyramids are located within the 14-ring channels sharing corners with the silicate framework. The solid-state 29Si MAS NMR spectrum of compound 1 was recorded; it shows the influence of the indium atoms in the second coordination sphere of the silicon on the chemical shift. Crystal data: 1, orthorhombic, Pna21 (No. 33), a = 12.4914(3) A, b = 16.8849(3) A, c = 10.2275(2) A, V = 2157.1(1) A3 and Z = 4; 2, monoclinic, P21/n (No. 14), a = 8.4041(3) A, b = 11.4919(4) A, c = 10.4841(3) A, beta = 90.478(2) degrees , V = 1012.5(1) A3 and Z = 2. 相似文献
768.
Takanori Iino Po-Lin Li Wen-Zhe Wang Jia-Huei Deng Yun-Chang Lu Fu-Jen Kao Yoichiroh Hosokawa 《Applied Physics A: Materials Science & Processing》2014,116(1):389-393
When an intense femtosecond laser is focused in a cell culture medium, shock wave, stress wave, and cavitation bubble are generated at the laser focal point. Cell–cell adhesion can be broken at the cellular level by the impacts of these factors. We have applied this breaking of the adhesion to an estimation of the cell–cell adhesion strength. In this application, it is important to identify which of these factors is the dominant factor that breaks the adhesion. Here we investigated this issue using streptavidin-coated microbeads adhering to a biotin-coated substrate as a mimic of the cell–cell adhesion. The results indicated that the break was induced mainly by the stress wave, not by the impact of the cavitation bubble. 相似文献
769.
Single crystals of benzophenone-2-furoyl hydrazone are grown by slow evaporation solution growth technique from ethanol at room temperature. It belongs to monoclinic system with the space group P21/c and the cell parameters are, a = 6.1631(3) Å, b = 13.1397(8) Å, c = 18.0030(11) Å and V = 1457.72(14) Å3. NMR spectral studies reveal the structure and powder XRD indicates the crystallinity of the specimen. The characteristic functional groups present in the molecule are confirmed by Fourier transform infrared spectroscopy. The crystals are transparent in the visible region having a lower optical cut-off at ∼406 nm and the band gap energies are estimated by the application of Kubelka–Munk algorithm. Thermal analysis by TG/DTA indicates the stability of the material. The scanning electron microscopy studies reveal the surface morphology of the as-grown crystal. Theoretical calculations were performed using Hartree–Fock method with 6-31G(d,p) as the basis set for to derive the optimized geometry, dipole moment and first-order molecular hyperpolarizability (β) values. 相似文献
770.