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81.
Experiments on uniform channel (VDS ≈ 0) MOSEFTs with resistance RDS show that the thermal noise is given by the normal Nyquist formula vn2 = 4kT RDSΔf. The modification to this formula which has been proposed is thus not necessary. The discrepancies are discussed.  相似文献   
82.
IMI Ti-230 (Ti + 2.5% Cu) is a commercial age-hardening alloy which is capable of withstanding considerable cold deformation in the solution heat treated condition. Age-hardening is associated with the coherent Ti2Cu precipitates. IMI recommends a duplex aging treatment comprising of nucleation (first aging) at 400°C for 24 hours followed by growth (second aging) for 8 hours at 475°C.

This investigation was aimed at designing a shorter and economical heat treatment cycle for achieving properties comparable to those obtained by the standard 32 hours duplex aging treatment as recommended by IMI. In addition, the effects of cold deformation at various stages in the aging cycle on the precipitation reaction were assessed by tensile property measurements.  相似文献   
83.
3D graphene, as a light substrate for active loadings, is essential to achieve high energy density for aqueous Zn‐ion batteries, yet traditional synthesis routes are inefficient with high energy consumption. Reported here is a simplified procedure to transform the raw graphite paper directly into the graphene‐like carbon film (GCF). The electrochemically derived GCF contains a 2D–3D hybrid network with interconnected graphene sheets, and offers a highly porous structure. To realize high energy density, the Na:MnO2/GCF cathode and Zn/GCF anode are fabricated by electrochemical deposition. The GCF‐based Zn‐ion batteries deliver a high initial discharge capacity of 381.8 mA h g?1 at 100 mA g?1 and a reversible capacity of 188.0 mA h g?1 after 1000 cycles at 1000 mA g?1. Moreover, a recorded energy density of 511.9 Wh kg?1 is obtained at a power density of 137 W kg?1. The electrochemical kinetics measurement reveals the high capacitive contribution of the GCF and a co‐insertion/desertion mechanism of H+ and Zn2+ ions. First‐principles calculations are also carried out to investigate the effect of Na+ doping on the electrochemical performance of layered δ‐MnO2 cathodes. The results demonstrate the attractive potential of the GCF substrate in the application of the rechargeable batteries.  相似文献   
84.
In this paper, according to the Maclaurin symmetric mean (MSM) operator, the dual MSM (DMSM) operator and the q-rung interval-valued orthopair fuzzy set (q-RIVOFS), we develop some novel MSM operators under the q-rung interval-valued orthopair fuzzy environment, such as, the q-rung interval-valued orthopair fuzzy MSM operator, the q-rung interval-valued orthopair fuzzy weighted MSM (q-RIVOFWMSM) operator, the q-rung interval-valued orthopair fuzzy DMSM operator, and the q-rung interval-valued orthopair fuzzy weighted DMSM operator. In addition, some precious properties and numerical examples of these new operators are given in detail. These new operators have the advantages of considering the interrelationship of arguments and can deal with multiple attribute group decision-making problems with q-rung interval-valued orthopair fuzzy information. Finally, a reality example for green suppliers selection in green supply chain management is provided to demonstrate the proposed approach and to verify its rationality and scientific.  相似文献   
85.
We present a scheme to generate the Bell state deterministically on remote transmon qubits coupled to different 1D superconducting resonators connected by a long superconducting transmission line. Using the coherent evolution of the entire system in the all-resonance regime, the transmission line need not to be populated with microwave photons which can robust against the long transmission line loss. This lets the scheme more applicable to the distributed quantum computing on superconducting quantum circuit. Besides, the influence from the small anharmonicity of the energy levels of the transmon qubits can be ignored safely.  相似文献   
86.

This article examines the hydromagnetic three-dimensional flow of viscous nanoliquid. A bidirectional linear stretching surface has been used to create the flow. Novel features regarding Brownian motion and thermophoresis have been studied by employing Buongiorno model to examine the slip velocity of nanoparticle. Viscous liquid is electrically conducting subject to uniform applied magnetic field. Problem formulation in boundary-layer region is performed for low magnetic Reynolds number. Simultaneous effects of constant heat flux and zero nanoparticles flux conditions are utilized at boundary. Appropriate transformations correspond to the strongly nonlinear ordinary differential expressions. The resulting nonlinear systems have been solved through the optimal homotopy analysis method. Graphs have been sketched in order to analyze that how the temperature and concentration profiles are affected by various physical parameters. Further the coefficients of skin-friction and heat transfer rate have been numerically computed and discussed. Our findings show that the temperature distribution has a direct relationship with the magnetic parameter. Moreover, the temperature distribution and thermal boundary-layer thickness are higher for hydromagnetic flow in comparison with the hydrodynamic flow.

  相似文献   
87.
This paper focuses on the identification problem for a class of bilinear-in-parameter systems with an additive noise modeled by an autoregressive moving average process. By using the over-parameterization model, the special form of the bilinear term can be obtained by the model equivalent transformation. Then, we use a decomposition of the model into two synthetic models in order to separate the effect of the two sets of parameters, i.e., the coefficients of the nonlinear basis functions from the parameters of the colored noise. Moreover, two decomposition based iterative algorithms are proposed to identify the unknown parameters. A numerical example is presented to confirm the effectiveness of the proposed methods.  相似文献   
88.
International Journal of Control, Automation and Systems - By means of the model equivalence theory, this paper proposes a model equivalence based least squares iterative algorithm for estimating...  相似文献   
89.
This article considers the identification problems of multivariable input nonlinear systems with unmeasured disturbances. For the identification difficulty caused by the crossproducts between the parameters of the linear block and the nonlinear block, the key term separation technique is adopted to separate the parameters of the nonlinear block from the parameters of the linear block. By combining the model decomposition technique and the hierarchical identification principle, a key term separation‐based maximum likelihood recursive extended stochastic gradient algorithm with reduced computational complexity is presented to estimate all the parameters directly. By introducing the multiinnovation identification theory, a key term separation‐based maximum likelihood multiinnovation extended stochastic gradient algorithm is proposed to improve the parameter estimation accuracy. The simulation results illustrate the effectiveness of the proposed methods.  相似文献   
90.
Wireless Personal Communications - Device to device (D2D) communication is one of the potentials to achieve the established standards for 5G. It represents a direct communication between two...  相似文献   
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