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This paper studies a real-world manufacturing problem, which is modeled as a bi-objective integer programming problem. The variables and constraints involved are usually numerous and dramatically vary according to the manufacturing data. It is very challenging to directly solve such large-scale problems using heuristic algorithms or commercial solvers. Considering that the decision space of such problems is usually sparse and has a block-like structure, we propose to use decomposition methods to accelerate the optimization process. However, the existing decomposition methods require that the problem has strict block structures, which is not suitable for our problem. To deal with problems with such block-like structures, we propose a game theory based decomposition algorithm. This new method can overcome the large-scale issue and guarantee convergence to some extent, as it can narrow down the search space and accelerate the convergence. Extensive experimental results on real-world industrial manufacturing planning problems show that our method is more effective than the world fastest commercial solver Gurobi. The results also indicate that our method is less sensitive to the problem scale comparing with Gurobi. [ABSTRACT FROM AUTHOR]

Assembling cellulose nanocrystals (CNCs) can induce solid-state photoluminescence based on Stokes scattering. Such photoluminescent materials are free of photo-quenching and show great potential in optical applications, whereas poor flexibility of assembled CNC arrays limits their applications. Here, a binary co-assembly of 1D nanoparticles and long-chain polymers was explored to produce the uniaxial CNC arrays into transparent poly(vinyl alcohol) (PVA) membranes, which enhanced the mechanical properties, especially ductility. Besides, the CNC assembly was controlled by adjusting the mass ratio between CNCs and PVA. The result indicated that co-assembling with PVA could improve the uniaxial orientation of CNC arrays, which played a crucial role in enhancing the emission quantum efficiency (EQE). Stretching the PVA/CNC membrane could further induce an enhancement in EQE together with a blue shift in excitation wavelength. The mechanism study on stimulation-response suggested that the EQE enhancement and blue shift came from the change in uniaxial orientation degree and periodicity of the CNC assembly, respectively. Since the stimulation-responsive enhancement in EQE (from ca. 40 to 60%) can even be observed by naked eyes, we believe such cellulose-based materials can be widely used in optical sensors. [ABSTRACT FROM AUTHOR]

We report theoretical study of the effects of energy relaxation on the tunneling current through the oxide layer of a two-dimensional graphene field-effect transistor. In the channel, when three-dimensional electron thermal motion is considered in the Schrödinger equation, the gate leakage current at a given oxide field largely increases with the channel electric field, electron mobility, and energy relaxation time of electrons. Such an increase can be especially significant when the channel electric field is larger than 1 kV/cm. Numerical calculations show that the relative increment of the tunneling current through the gate oxide will decrease with increasing the thickness of oxide layer when the oxide is a few nanometers thick. This highlights that energy relaxation effect needs to be considered in modeling graphene transistors. [ABSTRACT FROM AUTHOR]

The ferromagnetic transition temperatures have been measured on two bathes of perovskite manganese oxides such as (La1- x R x )2/3Ca1/3MnO3(R=Ce, Pr, Nd, etc.) and La2/3(Ca1- y Cd y )1/3MnO3. It is found that the (La1- x R x )2/3Ca1/3MnO3 samples have obviously different Curie temperature T C although their (rA) (the average A-site cation radius) are almost identical, and the T C in the system of (La1- x R x )2/3Ca1/3MnO3(R=Ce, Pr, Nd, etc.) and La2/3(Ca1- y Cd y )1/3MnO3. It is found that the (La1- x R x )2/3Ca1/3MnO3 compounds increases with increasing y although (rA) decreases slightly. It is suggested that the Curie temperature should be influenced by the average local A-site magnetic moment in the ferromagnetic perovskite manganite system. [ABSTRACT FROM AUTHOR]

The electrical resistance in zero magnetic field and magnetoresistance in different external magnetic fields have been measured in a temperature range of 77—300 K. It is found that the temperature dependence of magnetoresistance can be well described by a phenomenofogical formula of where the fitting parameters α, β vary as the external magnetic field H changes, E 0 is the activation energy, E 0/ k B = 1160 K, M s is the saturation magnetization, the temperature and magnetic field dependence of M/ M s is obtained by the mean-field expression. [ABSTRACT FROM AUTHOR]