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Light Propagation in the Second post-Newtonian Approximation of Scalar-Tensor Theory of Gravity

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Communications in Theoretical Physics 2011年第3期55卷 457-461页

作者： dong peng LI Lei Graduate University of the Chinese Academy of Sciences Beijing 100049 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Department of Physics Dalian Maritime University Dalian 116026 China

In this paper, we use the metric coefficients and the equation of motion obtained in the second post- Newtonian approximation of scalar-tensor theory to derive the second-order light propagation equation and the light deflection angle and compare it with previous works. These results are useful for precision astrometry missions like ASTROD, GALA, Darwin and SIM which aim at astrometry with micro-arcsecond and nano-aresecond accuracies, and need for the second post-Newtonian framework and ephemeris for observations to determine the stellar and spacecraft positions.

关键词： post-Newtonian approximation scalar-tensor theory light propagation

Self-Consistent Flow Shear Induced by Drift-Thermal Turbulence

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Chinese Physics Letters 1996年第8期13卷 598-601页

作者： peng Xiao-dong GAO Qing-di Southwestern Institute of Physics Chengdu 610041

The self-consistent poloidal flow shear induced by turbulence driven by impurity radiation has been studied analytically. A set of reduced equations is obtained. In our system, three equilibrium states exist. The first is the zero flow shear state, which is relevant to the behavior such as L mode, the second is the positive flow shear state, which is relevant to the behavior such as dithering H mode, and the third is the negative flow shear state, which is relevant to the behavior such as edge-localized modes.

关键词： flow Shear turbulence

Electrical characteristics of laminar propane flame during head-on quenching

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Science China(Technological Sciences) 2020年第8期63卷 1497-1508页

作者： GUO Li ZHAI Ming ZHANG YiChi dong peng School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The electrical characteristics of laminar propane flame during head-on quenching were investigated experimentally and computationally.A variable small electric field was applied between the burner and the quenching plate,which recorded flame current as a function of the height of the quenching plate,for both polarities,different premixed-air volume,and quenching plate *** detailed information of flame,such as the distribution of OH radical and main charged species(H3O+and e-)were obtained by using numerical *** results showed that during the head-on quenching,the resistance of the propane flame is on the order of 108Ω,the flame current increases with the increase of the premixed-air volume,and the effect of the quenching plate materials on the flame current is *** addition,it is found that the direction of the electric field has a significant influence on the flame current,indicating the"rectifier"characteristics of the ***,it is interestingly found that the trend of flame current for burner-(burner is negative)is more consistent with the trend of the maximum OH mole concentration than for burner+(burner is positive),which indicates that the trend of flame current for burner-can more accurately reflect the combustion state during head-on *** it would be a better choice to use burner as the negative electrode when diagnosing the combustion state with an applied electric field.

关键词： electrical characteristics laminar propane flame head-on quenching

Preparation of Polylactide/Poly(ether)urethane Blends with Excellent Electro-actuated Shape Memory via Incorporating Carbon Black and Carbon Nanotubes Hybrids Fillers

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Chinese Journal of Polymer Science 2018年第10期36卷 1175-1186页

作者： Yuan Wei Rui Huang peng dong Xiao-dong Qi Qiang Fu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University

In this work, hybrid conductive fillers of carbon black （CB） and carbon nanotubes （CNTs） were introduced into polylactide （PLA）/thermoplastic poly（ether）urethane （TPU） blend （70/30 by weight） to tune the phase morphology and realize rapid electrically actuated shape memory effect （SME）. Particularly, the dispersion of conductive fillers, the phase morphology, the electrical conductivities and the shape memory properties of the composites containing CB or CB/CNTs were comparatively investigated. The results suggested that both CB and CNTs were selectively localized in TPU phase, and induced the morphological change from the sea-island structure to the co-continuous structure. The presence of CNTs resulted in a denser CB/CNTs network, which enhanced the continuity of TPU phase. Because the formed continuous TPU phase provided stronger recovery driving force, the PLA/TPU/CB/CNTs composites showed better shape recovery properties compared with the PLA/TPU/CB composites at the same CB content. Moreover, the CB and CNTs exerted a synergistic effect on enhancing the electrical conduetivities of the composites. As a result, the prepared composites exhibited excellent electrically actuated SME and the shape recovery speed was also greatly enhanced. This work demonstrated a promising strategy to achieve rapid electrically actuated SME via the addition of hybrid nanoparticles with self-networking ability in binary PLA/TPU blends over a much larger composition range.

关键词： Polymer composites Shape memory polymer Co-continuous structure Self-networking behavior Hybrid filler

A granular-biomass high temperature pyrolysis model based on the Darcy flow

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Frontiers of Earth Science 2015年第1期9卷 114-124页

作者： Jian GUAN Guoli QI peng dong China Special Equipment Inspection and Research Institute Beijing 100013 China School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China

We established a model for the chemical reaction kinetics of biomass pyrolysis via the hightemperature thermal cracking of liquid products. We divided the condensable volatiles into two groups, based on the characteristics of the liquid prdoducts., tar and biomass oil. The effects of temperature, residence time, particle size, velocity, pressure, and other parameters on biomass pyrolysis and high-temperature tar cracking were investigated numerically, and the results were compared with experimental data. The simulation results showed a large endothermic pyrolysis reaction effect on temperature and the reaction process. The pyrolysis reaction zone had a constant temperature period in several layers near the center of large biomass particles. A purely physical heating process was observed before and after this period, according to the temperature index curve.

关键词： biomass pyrolysis high temperature pyrolysis model condensable volatile cracking Darcy flow

Modulation and enhancement of photonic spin Hall effect with graphene in broadband regions

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Chinese Physics B 2021年第3期30卷 260-265页

作者： peng dong Gaojun Wang Jie Cheng College of Electronic and Optical Engineering&College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Science New Energy Technology Engineering Laboratory of Jiangsu ProvinceNanjing University of Posts and TelecommunicationsNanjing 210023China Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province Nanjing 210023China

The photonic spin Hall effect(SHE)holds great potential applications in manipulating spin-polarized ***,the SHE is generally very weak,and previous studies of amplifying photonic SHE were limited to the incident light in a specific wavelength *** this paper,we propose a four-layered nanostructure of prism-graphene-air-substrate,and the enhanced photonic SHE of reflected light in broadband range of 0 THz–500 THz is investigated *** spin shift can be dynamically modulated by adjusting the thickness of air gap,Fermi energy of graphene,and also the incident *** optimizing the structural parameter of this structure,the giant spin shift(almost equal to its upper limit,half of the incident beam waist)in broadband range is achieved,covering the terahertz,infrared,and visible *** difference is that in the terahertz region,the Brewster angle corresponding to the giant spin shift is larger than that of infrared range and visible *** findings provide us with a convenient and effective way to tune the photonic SHE,and may offer an opportunity for developing new tunable photonic devices in broadband range.

关键词： photonic spin Hall effect graphene spin shift

Optimization of Electron Density and Temperature Profiles in Tokamaks via Safety Factor Profile

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Chinese Physics Letters 2001年第8期18卷 1101-1102页

作者： QIU Xiao-Ming peng Xiao-dong Southwestern Institute of Physics P.O.Box 432Chengdu 610041

The turbulent particle and thermal transport scaling laws are derived by means of Lagrangian invariant of trapped electron dynamics in tokamaks,which are in good agreement with experimental *** the basis of the two scaling laws,it is proposed that the optimization of electron density and temperature profiles can be achieved by designing a desirable safety factor profile.

关键词： Electron scaling Profiles

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高校工程项目数字智能化审计体系构建及应用

办公自动化 2025年第1期30卷 119-122页

作者：彭东伍济芬刘丽广西医科大学南宁530021

21世纪以来,随着科技的飞速进步,数字智能化已在医疗、教育、交通等各领域迅猛发展,为生活带来前所未有的变革。医疗诊断精准率的提升、自动驾驶安全性的提高以及智能机器人的普及应用都是智能化技术发展的生动例证。然而,在高校工程项... 详细信息

21世纪以来,随着科技的飞速进步,数字智能化已在医疗、教育、交通等各领域迅猛发展,为生活带来前所未有的变革。医疗诊断精准率的提升、自动驾驶安全性的提高以及智能机器人的普及应用都是智能化技术发展的生动例证。然而,在高校工程项目审计领域,尽管智能化技术的应用已受到广泛关注,但实际应用仍停留在初级阶段。传统的高校工程项目审计,无论是过程审计还是专项审计,都面临诸多的挑战。其中最突出的问题在于审计人员专业水平存在差异,容易导致工作效率低下,工作质量不高;数据处理与分析依赖于低效、易错的人工流程,审计人员往往需要手工处理大量的数据,不仅耗时、耗力,且易出错;此外,数据分析静态且滞后也使得审计人员难以实时预警潜在风险,从而影响审计工作的准确性和时效性。在此背景下,引入数字智能化技术,能为当下审计工作提供更加高效、便捷的审计方式,并把审计人员从庞大、繁冗的审计数据处理中解脱出来,使审计人员有更多的精力投入对重点问题的分析和判断上,因此,如何在未来实现工程项目智能化审计已成为一个新的课题。文章将从高校审计人员日常工作视角,结合工程项目专项审计特点,从工程项目审计体系构建、应用、功能实现等方面,运用VBA代码模拟软件分析,帮助工程项目审计人员打开思路,更好地应对新形势的挑战。

关键词：高校数字智能化工程审计软件代码

A deep reinforcement learning(DRL)based approach for well-testing interpretation to evaluate reservoir parameters

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Petroleum Science 2022年第1期19卷 264-278页

作者： peng dong Zhi-Ming Chen Xin-Wei Liao Wei Yu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing(CUP)Beijing102249China University of Texas at Austin Austin78731TexasUSA

Parameter inversions in oil/gas reservoirs based on well test interpretations are of great significance in oil/gas *** well test interpretations based on artificial intelligence are the most promising to solve the problem of non-unique *** this work,a new deep reinforcement learning(DRL)based approach is proposed for automatic curve matching for well test interpretation,by using the double deep Q-network(DDQN).The DDQN algorithms are applied to train agents for automatic parameter tuning in three conventional well-testing *** addition,to alleviate the dimensional disaster problem of parameter space,an asynchronous parameter adjustment strategy is used to train the ***,field applications are carried out by using the new DRL *** show that step number required for the DDQN to complete the curve matching is the least among,when comparing the naive deep Q-network(naive DQN)and deep Q-network(DQN).We also show that DDQN can improve the robustness of curve matching in comparison with supervised machine learning *** DDQN algorithm to perform 100 curve matching tests on three traditional well test models,the results show that the mean relative error of the parameters is 7.58%for the homogeneous model,10.66%for the radial composite model,and 12.79%for the dual porosity *** the actual field application,it is found that a good curve fitting can be obtained with only 30 steps of parameter adjustment.

关键词： Well testing Deep reinforcement learning Automatic interpretation Parameter evaluation