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Multi-baseline extended particle filtering phase unwrapping algorithm based on amended matrix pencil model and quantized path-following strategy

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Journal of Systems Engineering and Electronics 2019年第1期30卷 78-84页

作者： XIE Xianming zeng Qingning School of Information and Communication Guilin University of Electronic Technology

This paper proposes a new multi-baseline extended particle filtering phase unwrapping algorithm which combines an extended particle filter with an amended matrix pencil model and a quantized path-following strategy. The contributions to multibaseline synthetic aperture radar(SAR) interferometry are as follows: a new recursive multi-baseline phase unwrapping model based on an extended particle filter is built, and the amended matrix pencil model is used to acquire phase gradient information with a higher precision and lower computational cost, and the quantized path-following strategy is introduced to guide the proposed phase unwrapping procedure to efficiently unwrap wrapped phase image along the paths routed by a phase derivative variance map.

关键词： multi-baseline phase unwrapping interferometric synthetic aperture radar (InSAR) extended particle filter.

Generalized δ-entropy condition to Riemann solution for Chaplygin gas in traffic flow

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Applied Mathematics and Mechanics(English Edition) 2015年第3期36卷 353-364页

作者： Wancheng SHENG Ying zeng Department of Mathematics Shanghai University Department of Mathematics and Physics Quzhou University

The Riemann problem for the Aw-Rascle model in the traffic flow with the Delta initial data for the Chaplygin gas is studied. The solutions are constructed globally under the generalized Rankine-Hugoniot relations, the δ-entropy conditions, and the generalized δ-entropy conditions. A new Delta wave, which is called a primary Delta wave, is defined in some solutions. The primary Delta wave satisfies the generalized Rankine- Hugoniot relations and the generalized δ-entropy conditions. It generates initially from the Delta initial data, which either evaluates a Delta wave, whose weight becomes stronger and stronger, or disappears at a finite time.

关键词： generalized δ-entropy condition Riemann problem for Aw-Rascle model,generalized Rankine-Hugoniot relation Delta initial datum Chaplygin gas

2018 petroleum & chemical industry development report

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2606-2614页

作者： Chunyang zeng Qianlin Hu Chemical Industry Productivity Promotion Center of China Beijing 100723China China Petroleum Chemical Industry Federation Beijing 100723China

In 2018,the petroleum and chemical industries of China achieved steady economic *** main business income of the entire industry was 12.4 trillion CNY,an increase of 13.6%over the previous *** total profit was 83.93 billion CNY,an increase of 32.1%over the previous *** total national oil and gas production reached 334 million tons of oil equivalent,increasing by 2.4%*** the total production,crude oil production was 189 million tons,decreased 1.2%,and natural gas production was 161.02 billion cubic meters,increased 7.5%year on *** crude oil production was 462 million tons,an increase of 10.1%over the last *** gas production was 125.72 billion cubic meters,increased 31.9%.The annual processing capacity of crude oil was 604 million tons,up by 6.8%.The refined oil production was 360 million tons,up by 3.6%.The industry structure was optimized for production growth in 2018,the transformation and upgrading of enterprises and products structure adjustment were sped up,energy efficiency was improved,and overall industrial benefit was *** present,the economic operation of the industry is still not very stable,and downward pressure is still great,mainly being reflected in the overcapacity of some industries,high cost operation of enterprises,increased tax burden,and weak *** the slow recovery of the global economy and the key support of high-quality development through technological innovation,it is expected that the petroleum and chemical industry of China will achieve the general objective of steady growth in 2019.

关键词： China Petroleum and chemical industry Profit Main business income Production Consumption Technological innovation

Electrochemical conversion of organic compounds and inorganic small molecules

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Science China Chemistry 2024年第10期67卷 3223-3246页

作者： Weimei zeng Youai Qiu Department of Chemistry Nankai UniversityTianjin 300071China

Electrochemical synthesis presents a facile and sustainable strategy to produce valuable *** review summarizes the most recent advances in electrosynthesizing value-added compounds with inorganic small ***“small molecules”refers to a broad spectrum of chemicals,we mainly focus on the electrochemical conversion of CO_(2),H_(2)O/D_(2)O,NH_(3)and SO_(2)until March *** review intends to compare the results and display general trends throughout the field,with an emphasis on the substrate scope and mechanical ***,we propose several techniques and protocols that can enable a more fundamental understanding of the electrochemical reaction involving inorganic small molecules and help drive this methodology toward commercialization.

关键词： electrochemical synthesis inorganic small molecule organic synthesis carbon dioxide water

Entransy dissipation analysis of interfacial convection enhancing gas–liquid mass transfer process based on field synergy principle

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1777-1788页

作者： Dong Li Aiwu zeng State Key Laboratory of Chemical Engineering School of Chemical Engineering and Technology Tianjin University

An exploration of the gas CO2 absorbed into liquid ethanol accompanied with Rayleigh convection is performed by analyzing the mass entransy dissipation;this new statistical quantity is introduced to describe the irreversibility of mass transfer potential capacity. Based on the general advection–diffusion differential equation for an unsteady mass transfer process, the variation of the included angle between the velocity vector and concentration gradient fields is investigated to reveal the underlying mechanism of interfacial convection enhancing mass transfer. Results show some identical characteristics with the qualitative analyses of the synergy effects generated by the concentration and velocity fields after interfacial convection occurring for a boundary condition of fixed surface concentration. And the equivalent mass resistance for convective mass transfer process presents the similar variation with the reciprocal of instantaneous mass transfer coefficient. Accordingly, it is reasonable to be seen that mass transfer dissipation rate could be provided to assess the convection strength and explain fundamentally how Rayleigh convection improves mass transfer performance through establishing a close relationship between the mass transfer capacity and field synergy principle from the view of mass transfer theory.

关键词： Field synergy Mass entransy dissipation Equivalent mass resistance Interfacial convection Reinforcement

Studies on gas turbulence and particle fluctuation in dense gas-particle flows

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Acta Mechanica Sinica 2008年第3期24卷 251-260页

作者： Lixing Zhou Zhuoxiong zeng Department of Engineering Mechanics Tsinghua UniversityBeijing 100084 China Aeronautic and Mechanical Engineering College Nanchang Hangkong University Nanchang 330034 China

Particle fluctuation and gas turbulence in dense gas-particle flows are less studied due to complexity of the phenomena. In the present study, simulations of gas turbulent flows passing over a single particle are carried out first by using RANS modeling with a Reynolds stress equation turbulence model and sufficiently fine grids, and then by using LES. The turbulence enhancement by the particle wake effect is studied under various particle sizes and relative gas velocities, and the turbulence enhancement is found proportional to the particle diameter and the square of velocity. Based on the above results, a turbulence enhancement model for the particle-wake effect is proposed and is incorporated as a sub-model into a comprehensive two-phase flow model, which is then used to simulate dilute gas-particle flows in a horizontal channel. The simulation results show that the predicted gas turbulence by using the present model accounting for the particle wake effect is obviously in better agreement with the experimental results than the prediction given by the model not accounting for the wake effect. Finally, the proposed model is incorporated into another two-phase flow model to simulate dense gasparticle flows in a downer. The results show that the particle wake effect not only enhances the gas turbulence, but also amplifies the particle fluctuation.

关键词： Particle fluctuation Gas turbulence Densegas particle flows

Constitutive Model for the Thermo-viscoplastic Behavior of Hexagonal Close-Packed Metals with Application to Ti-6A1-4V Alloy

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Acta Mechanica Solida Sinica 2018年第3期31卷 369-382页

作者： Yunfei Li Xiangguo zeng Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621999China College of Architecture and Environment Sichuan UniversityChengdu 610065China

In this paper, a new physically based constitutive model is developed for hexagonal close-packed metals, especially the Ti-6Al-4V alloy, subjected to high strain rate and different temperatures based on the microscopic mechanism of plastic deformation and the theory of thermally activated dislocation motion. A global analysis of constitutive parameters based on the Latin Hypercube Sampling method and the Spearman＇s rank correlation method is adopted in order to improve the identification efficiency of parameters. Then, an optimal solution of constitutive parameters as a whole is obtained by using a global genetic algorithm composed of an improved niche genetic algorithm, a global peak determination strategy and the local accurate search techniques. It is concluded that the proposed constitutive modal can accurately describe the Ti-6Al-4V alloy＇s dynamic behavior because the prediction results of the model are in good agreement with the experimental data.

关键词： Hexagonal close-packed metals Physically based constitutive model Dislocationmotion High strain rate Ti-6Al-4V

Optimal reduction of anthropogenic emissions for air pollution control and the retrieval of emission source from observed pollutants Ⅰ. Application of incomplete adjoint operator

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Science China Earth Sciences 2018年第7期61卷 951-956页

作者： Qingcun zeng Lin WU Institute of Atmospheric Physics Chinese Academy of Sciences

The ultimate solution to anthropogenic air pollution depends on an adjustment and upgrade of industrial and energy structures. Before this process can be completed, reducing the anthropogenic pollutant emissions is an effective measure. This is a problem belonging to "Natural Cybernetics", i.e., the problem of air pollution control should be solved together with the weather prediction; however, this is very complicated. Considering that heavy air pollution usually occurs in stable weather conditions and that the feedbacks between air pollutants and meteorological changes are insufficient, we propose a simplified natural cybernetics method. Here, an off-line air pollution evolution equation is first solved with data from a given anthropogenic emission inventory under the predicted weather conditions, and then, a related "incomplete adjoint problem" is solved to obtain the optimal reduction of anthropogenic emissions. Usually, such solution is sufficient for satisfying the air quality and economical/social requirements. However, a better solution can be obtained by iteration after updating the emission inventory with the reduced anthropogenic emissions. Then, this paper discusses the retrieval of the pollutant emission source with a known spatio-temporal distribution of the pollutant concentrations, and a feasible mathematical method to achieve this is proposed. The retrieval of emission source would also help control air pollution.

关键词： Air pollution Optimal control Source retrieval Incomplete adjoint operator

Integrated dynamic shared protection algorithm for GMPLS networks

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1264-1271页

作者： Wang Yan zeng Jiazhi Coll. of Computer Science and Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

The path protection approach is widely investigated as a survivability solution for GMPLS networks, which has the advantage of efficient capacity utilization. However, there is a problem of the path protection approach that searching a disjoint backup path for a primary path is often unsuccessful. In order to resolve this problem, an integrated dynamic shared protection （IDSP） algorithm is proposed. The main idea of the proposed algorithm is that the path protection approach is first used to establish a backup path for the primary path; if the establishment is unsuccessful, then the primary path is dynamically divided into segments whose hop count are not fixed but not more than the limitation calculated by the equations introduced. In this proposal, backup bandwidth sharing is allowed to improve the capacity utilization ratio, which makes the link cost function quite different from previous ones. Simulation experiments are presented to demonstrate the efficiency of the proposed method compared with previous methods. Numerical results show that IDSP can not only achieve low protection failure probability but can also gain a better tradeoff between the protection overbuild and the average recovery time.

关键词： generalized multi-protocol label switching protection hop count primary path backup path