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Zhang J.,Hunan First Normal University | He J.,Guangdong University of Petrochemical Technology
IEEE Photonics Journal | Year: 2017

In this paper, we propose a new kind of circular Airy beam whose spectrum is imposed an initial quadratic phase modulation (QPM). Unlike common abruptly autofocusing beams, we find that such modulated circular Airy beams (MCAB) at image plane, i.e., initial plane, may be morphed into conventional Airy patterns or Bessel-like patterns in spatial regime, depending on the magnitude of QPM. We further investigate the propagation characteristics of the MCAB both analytically and numerically. It is found that the focal intensity, as well as the size of focal spot, do not change with the QPM, but the latter greatly affects the focal trajectory and the focal position of MCAB. In particular, we show that, for the case of Airy pattern, MCAB will exhibit a dual abruptly focusing behaviors having the same focal intensity as well as size of focal spot, where there is one focus behind the image plane, and the another one is in front of it. On the other hand, for the case of Bessel-like pattern, the dual abruptly foci are simultaneously observed behind the image plane for positive QPM but in front of it for negative QPM, thus leading to the formation of an elegant optical bottle with paraboloidal shape. Such novel dual focusing behaviors are expected to be applied in the field of optical trapping and particle acceleration. © 2016 IEEE.

Zhao J.-Y.,Guangdong University of Petrochemical Technology
CIE 2016: 46th International Conferences on Computers and Industrial Engineering | Year: 2016

With simulation model of the manufacturing process in Fluorine Roller Workshop by Witness, which was run on computer, we can obtain such information of the production logistics system as manufacturing outcome, rate of equipment utilization, as well as some issues which were related to material handling and production bottleneck. By the analysis of the simulation results, had pointed out each kinds of question existed in the production process and came up with the improvement plan, simulation model's running results show that the improvement plan can make the production capacity increase by 30%.

Yu D.,Tianjin University | Chen G.,Tianjin University | Yu W.,Nuclear Power Institute of China | Li D.,Guangdong University of Petrochemical Technology | Chen X.,Tianjin University
International Journal of Plasticity | Year: 2012

Experimental results of monotonic uniaxial tensile tests at different strain rates and the reversed strain cycling test showed the characteristics of rate-dependence and cyclic hardening of Z2CND18.12N austenitic stainless steel at room temperature, respectively. Based on the Ohno-Wang kinematic hardening rule, a visco-plastic constitutive model incorporated with isotropic hardening was developed to describe the uniaxial ratcheting behavior of Z2CND18.12N steel under various stress-controlled loading conditions. Predicted results of the developed model agreed better with experimental results when the ratcheting strain level became higher, but the developed model overestimated the ratcheting deformation in other cases. A modified model was proposed to improve the prediction accuracy. In the modified model, the parameter mi of the Ohno-Wang kinematic hardening rule was developed to evolve with the accumulated plastic strain. Simulation results of the modified model proved much better agreement with experiments. © 2011 Elsevier Ltd. All rights reserved.

Liu W.,Guangdong University of Petrochemical Technology | Chen C.,Guangdong University of Petrochemical Technology | Zhang Q.,Guangdong University of Petrochemical Technology
Organic and Biomolecular Chemistry | Year: 2011

A novel reaction including the sequence of hydroamination of alkynes and subsequent oxidative C-H bond functionalization has been developed in the presence of diacetoxyiodobenzene (DIB). The method allows us to synthesize a wide range of tetrasubstituted (E)-alkenes and provides a potential method to construct densely functionalized carbonyl compounds. © 2011 The Royal Society of Chemistry.

Wang F.,Guangdong University of Petrochemical Technology
Advances in Science and Technology of Water Resources | Year: 2014

In order to investigate the fractal features of meandering rivers, the divider dimension was used as a parameter to describe the internal structure of river patterns. It is proven that the divider dimension is equal to the Housdorff dimension. The divider dimensions of the lower Jingjiang River and its three local sections in six historical periods from 1496 to 2013 were computed, quantitatively characterizing the evolution laws of the river patterns. The results show that, compared with the sinuosity coefficient, the divider dimensions can better characterize the river pattern and its evolution laws.

Chen H.,Guangdong University of Petrochemical Technology | Hu S.,Guangdong University of Petrochemical Technology
Optics Communications | Year: 2014

The optical solitons in parity-time (PT) symmetric mixed Bessel linear potential and modulated nonlinear lattices are studied, including linear case, and self-focusing modulated nonlinear lattices' cases. For linear case, the PT-breaking points, the eigenvalues and eigenfunction for different modulated depths of PT symmetry Bessel complex potential, are obtained numerically. The eigenvalue for linear case is equal to the critical propagation constant b c of soliton existence. With increasing of the depth of the nonlinear lattices, the power of fundamental solitons decreases and the beam width changes little, but the power of multipole solitons increases and the beam width decreases. Fundamental solitons are stable in the whole region and multipole solitons are stable with the propagation constants close to bc. The range of multipole solitons stability decreases with increasing of the depth of the nonlinear lattices. © 2014 Elsevier B.V.

Chen H.,Guangdong University of Petrochemical Technology | Hu S.,Guangdong University of Petrochemical Technology
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2016

We investigate the properties in two-dimensional (2D) special parity-time (PT) symmetric complex potentials. The linear case of this special 2D PT-symmetric complex potential and self-focusing nonlinear cases are discussed. For linear case, the eigenvalues and eigenfunction for different loss or gain level of the PT-symmetric complex potentials are obtained numerically. For nonlinear cases, the existence of asymmetric solitons and PT-symmetric solitons is studied in this PT symmetric system. The eigenvalue for linear case is equal to the critical propagation constant bc of existing PT-symmetric solitons. When the PT-symmetric soliton's propagation constant reaches a certain threshold bc1, a branch of asymmetric solitons can bifurcate out from the branch of PT-symmetric solitons. © 2015 Elsevier B.V. All rights reserved.

Tian H.,Guangdong University of Petrochemical Technology | Liao Z.,Guangdong University of Petrochemical Technology
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2013

In order to efficiently utilize agricultural biomass, thermogravimetry experimentation analysis of corn stalks, corn cobs, straw, lychee bar, and longan sticks and its mixed fuel was performed by using the TG-DTG-DSC (Thermogravimetric-Differential Thermogravimetric-Differential Scanning Calorimetry) thermal analysis technology. The combustible characteristics, ignition characteristics, burnout characteristics and synthetic combustion characteristics were investigated, and the combustion kinetics parameters were identified. The results show that the early burning DTG curves of corn stalks and corn cob have two peaks and three peaks, respectively, and the burning DTG curves of straw, longan sticks, and lychee strip each have only one peak. The mixed fuels prophase similar combustion characteristics of corn stalks, straw, and lychee bar show that the three fuels are suitable co-combustion. DSC curves of corn stalks S1 and straw S3 both have one endothermic peak late in the combustion, and the post-combustion needs to absorb more heat in order to maintain its combustion, which indicates that herbaceous biomass post-combustion stability is poor and not suitable for separate combustion. The DSC curve characteristics of wood-based biomass show that wood-based biomass has higher post-combustion stability. The combustible characteristics index and ignition characteristics index of corn stalks are both the largest, and their ignition temperature is the lowest, resulting in excellent pre-combustion performance. The burnout characteristic index of lychee bar is the largest and its burnout rate is the best, but its early combustion characteristics are not easy to catch fire and burn. The synthetic combustion characteristics of corncob are the best. The low-temperature phase of the reaction order is about 1.0-1.2, the high temperature phase of the reaction order is approximately 0.5-0.8, and the corresponding reaction activation energy is larger at the low temperature phase than that at the high temperature phase. The early biomass burning is a homogeneous fire and the late biomass burning belongs to a multiphase fire. The late stability of pure burning straw biomass is bad, but adding straw biomass with wood biomass is conducive to its pre-combustion of mixed fuels. The study results can provide guidance for the combustion and utilization of agricultural biomass.

Wende K.,Guangdong University of Petrochemical Technology
International Journal of Wireless and Mobile Computing | Year: 2016

A preferential vector algorithm of particle swarm with hierarchical reinforcement learning is proposed to solve the balance problem of global searching range and local searching precision, and the problem of fixedly adjusting strategy of inertia weight. Firstly, the preferential particle position with crossover operation was introduced on the standard particle swarm algorithm. The sequential adding operations on single step of particle position were divided into the seeking of middle particles. The operations of crossover and mutation were combined to keep the elite particle swarm. Secondly, the adjusting strategies of inertia weight were treated as the actions. The hierarchical learning was executed in every iteration of particle swarm and the strategy with maximal discounted profit was selected. The experiment proved the validity of the algorithm. © 2016 Inderscience Enterprises Ltd.

Hu S.,Guangdong University of Petrochemical Technology | Hu W.,South China Normal University
Journal of Physics B: Atomic, Molecular and Optical Physics | Year: 2012

Optical solitons in the parity-time (PT)-symmetric Bessel complex potential are studied, including the linear case, and self-focusing and self-defocusing nonlinear cases. For the linear case, the PT-symmetric breaking points, eigenvalues and the eigenfunction for different modulated depths of the PT-symmetric Bessel complex potential are obtained numerically. The PT-symmetric breaking points increase linearly with increasing the real part of the modulated depths of the PT potential. Below the PT-symmetric breaking points, the eigenfunctions of linear modes are symmetrical; however, the symmetries of the eigenfunction break above the PT-symmetric breaking points. For nonlinear cases, the existence and stability of fundamental and multipole solitons are studied in self-focusing and self-defocusing media. The eigenvalue for the linear case is equal to the critical propagation constant b c of the existing soliton. Fundamental solitons are stable in the whole region and multipole solitons are stable with the propagation constants being close to b c both for self-focusing and self-defocusing nonlinearities. The range of solitons stability decreases with an increase of the number of the intensity peaks of the solitons. © 2012 IOP Publishing Ltd.

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