Dialectic operator fuzzy logic (DOFL) is presented which is relevant,paraconsistent and nonmonotonic.DOFL can vividly describe the belief revision in the cognitive process and can infer reasonably well while the knowledge is inconsistent,imprecise or incomplete. 相似文献
The performance of thermoelectric (TE) coolers is determined by the figure of merit of the TE materials ZT. In order to obtain the optimal performance of a superlattice microcooler, both the superlattice structure and the device were optimized in the design and the fabrication process. The thermal conductivities of InGaAs/InGaAsP superlattices with different periodic lengths were measured with the 3omega method. The result indicates that the superlattice at a certain periodic length has minimal thermal conductivity, which, in general, corresponds to an enhanced ZT. A 1D model was utilized to investigate the significant parameters in microcoolers. Based on the modeling results, a set of superlattice microcoolers were fabricated. The maximum cooling temperature that was reached is 0.76degC for the optimized cooler at room temperature. 相似文献
The structural, dielectric and piezoelectric properties of （1-x）（Bi1/2Na1/2） TiO3-xBaTiO3 ceramics were investigated for the compositional range, x=0.02, 0.04, 0.06, 0.08, 0.10. The samples were synthesized by a conventional solid-state reaction technique. All compositions show a single perovskite structure, and X-ray powder diffraction patterns can be indexed using a rhombohedral structure. Lattice constants and lattice distortion increase while the amount of BaTiO3 increases. The X-ray diffraction results show the morphotropic phase boundary （MPB） of （1-x）（Bi1/2Na12） TiO3-xBaTiO3 exists in near x=0.06-0.08. Temperature dependence of dielectric constant eT33/ε0 measurement reveals that all compositions experience one structural phase and two ferroelectric phases transition below 400℃： rhombohedral （or rhombohedral plus tetragonal） ferroelectric phase ←→ tetragonal antiferroelectric phase ←→ tetragonal paraelectric phase. Relaxor behaviors exist in the course of ferroelectric to antiferroelectric phase transition. Dielectric and piezoelectric properties are enhanced in the MPB range for （ 1-x）（Bi1/2Na1/2）TiO3-xBaTiO3. 相似文献
Optimum detectors for pilot symbol assisted modulation (PSAM) signals in Rayleigh and Rician fading channels are derived. Conventional PSAM as used on Rayleigh fading channels is also employed on Rician fading channels. It is shown that the conventional PSAM receiver is optimal for binary phase shift keying in Rayleigh fading but suboptimal for Rician fading and suboptimal for 16-ary quadrature amplitude modulation in Rayleigh fading. The optimum PSAM signal detector uses knowledge of the specular component and also jointly processes the pilot symbols and the data symbol. The performance of the optimum detector is analyzed and compared with that of the conventional detector. It is concluded that substantial gains can be achieved by exploiting knowledge of the specular component while joint processing of the data symbol with the pilot symbols may offer small benefits. 相似文献
Photoanodes, which are used in photoelectrochemical (PEC) water splitting, have been shown to be applicable in the construction of a PEC biosensing platform. This was realized by replacing water oxidization with oxidation of an appropriate test molecule. Here, we have demonstrated the feasibility of adopting photoanodes consisting of zinc oxide nanorods arrays decorated with plasmonic gold nanoparticles (Au NPs@ZnO NRs) for the self-powered PEC bioanalysis of glutathione (GSH) in phosphate-buffered saline (PBS) at an applied bias potential of 0 V vs. Ag/AgCl. This heterostructure exhibited enhanced PEC properties because of the introduction of the Au/ZnO interface. Under visible light illumination, hot electrons from surface-plasmon resonance (SPR) at the Au NP surface were injected into the adjacent ZnO and subsequently driven to the photocathode. Under ultraviolet (UV) light illumination, the photogenerated electrons in ZnO tended to transfer to the fluorine-doped tin oxide due to the step-wise energy band structure and the upward energy band bending at the ZnO/ electrolyte interface. These results indicate that plasmonic metal/semiconductor heterostructure photoanodes have great potential for self-powered PEC bioanalysis applications and extended field of other photovoltaic beacons.
