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231.
232.
Traditional studies in data envelopment analysis (DEA) view systems as a whole when measuring the efficiency, ignoring the operation of individual processes within a system. This paper builds a relational network DEA model, taking into account the interrelationship of the processes within the system, to measure the efficiency of the system and those of the processes at the same time. The system efficiency thus measured more properly represents the aggregate performance of the component processes. By introducing dummy processes, the original network system can be transformed into a series system where each stage in the series is of a parallel structure. Based on these series and parallel structures, the efficiency of the system is decomposed into the product of the efficiencies of the stages in the series and the inefficiency slack of each stage into the sum of the inefficiency slacks of its component processes connected in parallel. With efficiency decomposition, the process which causes the inefficient operation of the system can be identified for future improvement. An example of the non-life insurance industry in Taiwan illustrates the whole idea. 相似文献
233.
Let n > 1 and G be the group SU(n) or Sp(n). This paper constructs compact symplectic manifolds whose symplectic quotient under a Hamiltonian G-action does not inherit the strong Lefschetz property. 相似文献
234.
Yuan-Fong Chou Chau Chung-Ting Chou Chao Hai-Pang Chiang Chee Ming Lim Nyuk Yoong Voo Abdul Hanif Mahadi 《Journal of nanoparticle research》2018,20(7):190
We have investigated numerically the plasmonic effect on a two-dimensional periodic array of metallic nanostructures. The unit cell of the array has an Ag nanosphere and nanorod pair formed in a single structure. Three-dimensional finite element method is used for the study on the sensing performance within the optical spectra. The study takes into account the influences of the structural and material parameters, the rotational angle of the metal nanostructure, the number of metal nanostructure per unit cell, and the localized surface plasmon resonances. The proposed nanostructures function as a refractive index sensor with a sensitivity of 400 nm/RIU (RIU is the refractive index unit), showing the characteristics of low transmittance (T?=?3.90%), high absorptance (A?=?94.5%), and near-zero reflectance (R?=?0.15%), could be achieved by a triangular arrangement of nanostructures within a unit cell. We also show how the tailoring of the structural parameters relates to the specific sensing schematics of the sensor. 相似文献
235.
Chiang‐Jui Chu Pei‐Yun Chung Mu‐Huan Chi Yi‐Huei Kao Jiun‐Tai Chen 《Macromolecular rapid communications》2014,35(18):1598-1605
Block copolymers have been extensively studied over the last few decades because they can self‐assemble into well‐ordered nanoscale structures. The morphologies of block copolymers in confined geometries, however, are still not fully understood. In this work, the fabrication and morphologies of three‐dimensional polystyrene‐block‐polydimethylsiloxane (PS‐b‐PDMS) nanostructures confined in the nanopores of anodic aluminum oxide (AAO) templates are studied. It is discovered that the block copolymers can wet the nanopores using a novel solvent‐annealing‐induced nanowetting in templates (SAINT) method. The unique advantage of this method is that the problem of thermal degradation can be avoided. In addition, the morphologies of PS‐b‐PDMS nanostructures can be controlled by changing the wetting conditions. Different solvents are used as the annealing solvent, including toluene, hexane, and a co‐solvent of toluene and hexane. When the block copolymer wets the nanopores in toluene vapors, a perpendicular morphology is observed. When the block copolymer wets the nanopores in co‐solvent vapors (toluene/hexane = 3:2), unusual circular and helical morphologies are obtained. These three‐dimensional nanostructures can serve as naontemplates for refilling with other functional materials, such as Au, Ag, ZnO, and TiO2.
236.
Nai-Hsiang Sun Chia-Ming Hu Jung-Sheng Chiang Wen-Fung Liu Jiun-Jie Liau Shih-Chiang Lin 《Fiber and Integrated Optics》2014,33(1-2):47-55
AbstractThe experimental results of the radiation for second-order fiber Bragg gratings, which are made of a single-mode photosensitive fiber (PS-1500; Fiber-Core Corp.) and a single-mode fiber (SMF-28; Corning Inc.), by a phase mask writing fabrication technique are explored. For PS-1500 fiber Bragg gratings, the maximum radiation efficiency of ?23.5 dB at resonance λ = 1,539.34 nm with a very narrow bandwidth (about 0.02 nm) are measured from a 10-mm-diameter photo-detector, while for SMF-28 fiber Bragg gratings, the maximum radiation efficiency is ?34.6 dB (λ = 1,538.03 nm) with a bandwidth of 0.06 nm. The total efficiencies of the radiation are about ?16.8 dB for PS-1500 fiber Bragg gratings and ?28.1 dB for SMF-28 fiber Bragg gratings. 相似文献
237.
Ultrashort TE (UTE) sequences allow direct visualization of tissues with very short T2 relaxation times, such as tendons, ligaments, menisci, and cortical bone. In this work, theoretical calculations, simulations, and phantom studies, as well as in vivo imaging were performed to maximize signal-to-noise ratio (SNR) for slice selective RF excitation for 2D UTE sequences. The theoretical calculations and simulations were based on the Bloch equations, which lead to analytic expressions for the optimal RF pulse duration and amplitude to maximize magnetic resonance signal in the presence of rapid transverse relaxation. In steady state, it was found that the maximum signal amplitude was not obtained at the classical Ernst angle, but at an either lower or higher flip angle, depending on whether the RF pulse duration or amplitude was varied, respectively. 相似文献
238.
Lin SH Yang CI Kuo TS Chiang MH Hsu KC Lu KL 《Dalton transactions (Cambridge, England : 2003)》2012,41(5):1448-1450
The self-adaptation of manganese-chloride arrangement with the tripodal ligand 1,3,5-tris(benzimidazoyl-1-ylmethyl)-2,4,6-trimethylbenzene (Me(3)-TBzIm) afforded a rare 3D metal-organic framework, [Mn(5)Cl(10)(Me(3)-TBzIm)(4)](n) (1) showing a high spin ground state with S = 15/2. 相似文献
239.
Perera PN Schmidt M Chiang VL Schuck PJ Adams PD 《Analytical and bioanalytical chemistry》2012,402(2):983-987
A new robust, noninvasive, Raman microspectroscopic method is introduced to analyze the structure of native lignin. Lignin
spectra of poplar, Arabidopsis, and Miscanthus were recovered and structural differences were unambiguously detected. Compositional analysis of 4-coumarate-CoA ligase suppressed
transgenic poplar showed that the syringyl-to-guaiacyl ratio decreased by 35% upon the mutation. A cell-specific compositional
analysis of basal stems of Arabidopsis showed similar distributions of S and G monolignols in xylary fiber cells and interfascicular cells. 相似文献