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Evolutionary-assisted reinforcement learning for reservoir real-time production optimization under uncertainty

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Petroleum Science 2023年第1期20卷 261-276页

作者： Zhong-Zheng Wang Kai Zhang Guo-Dong Chen Jin-Ding Zhang Wen-Dong Wang Hao-Chen Wang Li-Ming Zhang Xia Yan Jun Yao School of Petroleum Engineering China University of PetroleumQingdao266580ShandongChina Qingdao University of Technology Qingdao266520ShandongChina The University of Hong Kong 999077Hong KongChina

Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery *** existing methods could produce high-optimality results,they cannot be applied to real-time optimization for large-scale reservoirs due to high computational *** addition,most methods generally assume that the reservoir model is deterministic and ignore the uncertainty of the subsurface environment,making the obtained scheme unreliable for practical *** this work,an efficient and robust method,namely evolutionaryassisted reinforcement learning(EARL),is proposed to achieve real-time production optimization under ***,the production optimization problem is modeled as a Markov decision process in which a reinforcement learning agent interacts with the reservoir simulator to train a control policy that maximizes the specified *** deal with the problems of brittle convergence properties and lack of efficient exploration strategies of reinforcement learning approaches,a population-based evolutionary algorithm is introduced to assist the training of agents,which provides diverse exploration experiences and promotes stability and robustness due to its inherent *** with prior methods that only optimize a solution for a particular scenario,the proposed approach trains a policy that can adapt to uncertain environments and make real-time decisions to cope with unknown *** trained policy,represented by a deep convolutional neural network,can adaptively adjust the well controls based on different reservoir *** results on two reservoir models show that the proposed approach not only outperforms the RL and EA methods in terms of optimization efficiency but also has strong robustness and real-time decision capacity.

关键词： Production optimization Deep reinforcement learning Evolutionary algorithm Real-time optimization Optimization under uncertainty

Secure Localization Technology Based on Dynamic Trust Management in Wireless Sensor Networks

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Chinese Journal of Electronics 2021年第4期30卷 759-768页

作者： LI Peng YU Xiaotian XU He WANG Ruchuan School of Computer Science and Technology Nanjing University of Posts and Telecommunications Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks

Wireless sensor networks have critical applications in various fields, and the algorithm of their secure localization has become a vital technology to support a network. In the light of the self-organization, random deployment and dynamic topology, the localization process is vulnerable to various kinds of malicious attacks. The model of dynamic trust management for a given node is proposed to deal with security concerns in wireless sensor networks. The trust computation is divided into three stages, which are the stage of trust initialization,trust establishment, and trust evolution. The initial value of a global trust relationship is established through a corresponding global trust relation graph in the initial stage of trust. The trust value of each node is calculated by the attribute value in the stage of trust establishment. In the evolution of trust, the iterative process of trust value is accelerated via the finite state machine. Compared with the existing wireless sensor networks, simulation results show that the proposed security localization technology method can resist many kinds of attacks with low communication and time consumption.

关键词： Wireless sensor networks Secured localization Dynamic trust management Finite state machines

Development of self-generated proppant based on modified low-density and low-viscosity epoxy resin and its evaluation

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Petroleum Science 2022年第5期19卷 2240-2252页

作者： Jia-Cheng Fan Zhan-Qing Qu Tian-Kui Guo Ning Qi Ming Chen Jian Hou Ji-Jiang Ge Xiao-Qiang Liu Ji-Wei Wang College of Petroleum Engineering China University of PetroleumQingdao266580ShandongChina Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China

Hydraulic fracturing is a critical technology for the economic development of unconventional oil and gas *** main factor influencing fracture propping and reservoir stimulation effect is proppant *** increasing depth of fractured oil and gas reservoirs is causing growing difficulty in hydraulic ***,the migration of conventional proppants within the fracture is always limited due to small fracture width and rigid proppant ***,proppants with good transportation capacity and fracture propping effects are ***,a novel self-generated proppant based on toughened low-viscosity and low-density epoxy resin was developed to satisfy this ***,proppant performances were ***-viscosity and low-density epoxy resin was generated when the thiol-ene click chemical reaction product of eugenol and 1-thioglycerol reacts with the ***,the resin was toughened with graphite particles to increase its compressive strength from50.8 to 72.1 MPa based on micro-cracking mechanism and crazing-nail anchor *** adduct of diethylene triamine and butyl glycidyl ether and the Si O2 nanoparticles were treated as the curing agent and emulsifier respectively to form the *** emulsion is transformed into solid particles of various sizes within a reservoir to prop the *** shows good migration capacity of this self-generated proppant due to the low density of epoxy resin.

关键词： Low-viscosity and low-density epoxy resin Resin toughening Self-generated proppant Performance evaluation

Spatial pattern and utility of Populus euphratica seed rain:a simulation study combined with field investigations

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Forestry Studies in China 2012年第3期14卷 169-179页

作者： HAO Peng LI Jing-wen ZHOU Wei-lei LIU Qian-wen ZHANG Yu-bo Key Laboratory for Silviculture and Conservation of the Ministry of Education Beijing Forestry UniversityBeijing 100083E R.China Inner Mongolia Research Academy of Environmental Sciences Hohhot 010011P.R.China

Seed dispersal is a fundamental process affecting destinies of seeds and seedlings, as well as regeneration dynamics and distribution patterns of communities. Recently however, declining Populus euphratica forests have failed to regenerate by seeding, while the spatial pattern and utility of their seed rains are unclear. In this study, we designed a model to simulate seed rains based on field investigations by fitting our observations to a normal distribution and testing the model with data from three years, with ac- ceptable results. We examined the simulated results of dispersed seeds patterns on the classification of three factors, i.e., density of Sophora alopecuroides, surface soil moisture and surface soil salinity. The results of seed rain simulation show that over 70% of seeds were dispersed and confined to each of the three plots where their mother trees located. The proportion of 3：7 seeds dispersed inside and outside each plots remained largely unaltered. The differences in the amounts of dispersed seed among the different levels of each of the factors were not significant, although the distributing pattern of P. euphratica in each plot varied. Therefore, in P. eu- phratica communities, the amount of seed does not become a constraint in subsequent germination, although the surface environment does. We conclude that successful P. euphratica seed regeneration relies on less than 30% of seeds dispersed over longer distance to colonize favorable growth habitats.

关键词： Populus euphratica forest seed rain spatial pattern utility wind direction

Controllable Morphology Tailoring with Solvothermal Method Toward LiMnPO_(4)/C Cathode Materials for Improved Performance and Favorable Thermostability

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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 790-800页

作者： Wei Yang Xiulian Qiu Chengyun Wang Jinhao Ye Jihua Zhu Hanbo Zou Shengzhou Chen School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou510006China GAC Automotive Research and Development Center Guangzhou511434China Sunwoda Electronics Co. LtdShenzhen518107China

An environmentally friendly method for the synthesis of LiMnPO_(4)/C anode material for lithium-ion batteries by solvothermal method is *** modification of the morphology of this precursor is altered by changing the ratio of the conditioning solvent(water-ethylene glycol solution)and the order of material *** glycol(EG)exerts a considerable influence on synthesizing LiMnPO_(4)/C flake-like nanocrystal,which benefits the extraction/insertion reaction of lithium ions and improves the electrochemical activity and electrochemical performance of LiMnPO_(4)/C *** the solvent composition is H_(2)O:EG=1:3,exhibiting exceptional charge/discharge performance and rate capability,the specific discharge capacities are 155.8,153.7,148.8,141.4,129.5,and 112.6 mAh g^(−1) at the 0.1,0.2,0.5,1,2,and 5 C rates,*** the charge-discharge rate returns to 0.1 C,the LiMnPO_(4)/C material shows a reversible discharge specific capacity of 153.7 mAh g^(−1).Differential scanning calorimetry(DSC)tests verify that the thermodynamic stability of the prepared LiMnPO_(4)/C(LMP)and commercial LiFePO_(4)(LFP)materials is better than that of commercial nickel-cobalt-aluminum(NCA)ternary *** prepared LiMnPO_(4)/C composites have high electrochemical capacity and cycle stability.

关键词： LiMnPO_(4)/C solvothermal method Ethylene glycol Lithium-ion diffusion Thermostability

Interface-engineered MoS_(2)/CoS/NF bifunctional catalysts for highly-efficient water electrolysis

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Journal of Energy Chemistry 2022年第12期75卷 16-25,I0002页

作者： Wenxia Chen Xingwang Zhu Rui Wang Wei Wei Meng Liu Shuai Dong Kostya Ken Ostrikov Shuang-Quan Zang School of Chemistry and Chemical Engineering Henan Key Laboratory of Biomolecular Recognition and SensingHenan D&A Engineering Center of Advanced Battery MaterialsShangqiu Normal UniversityShangqiu 476000HenanChina Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001HenanChina College of Environmental Science and Engineering Yangzhou UniversityYangzhou 225009JiangsuChina School of Chemistry and Physics and Centre for Materials Science Queensland University of Technology(QUT)BrisbaneQLD 4000Australia

The utilization of non-noble metal catalysts with robust and highly efficient electrocatalytic activity for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)are extremely important for the large-scale implementation of renewable energy *** of bifunctional electrocatalysts on both anode and cathode electrodes remains a significant ***,we report on a novel and facile strategy to construct the ordered and aligned MoS_(2)nanosheet-encapsulated metal–organic frameworks(MOFs)derived hollow CoS polyhedron,in-situ grown on a nickel foam(NF).The starfish-like MoS_(2)/CoS/NF heterojunctions were formed due to the ordered growth of the material caused by NF *** optimized 2-MoS_(2)/CoS/NF heterojunction exhibits robust bifunctional electrocatalytic activity with a low overpotential of 67 and 207 m V toward the HER and OER at 10 mA cm^(-2),and the long-term stability,which exceeds most of the reported bifunctional *** high electrocatalytic performance arises due to the synergistic effect between the MoS_(2)and CoS phases across the interface,the abundant active sites,as well as the hierarchical pore framework,which collectively enhance the mass and electron transfer during the *** work provides a promising approach to fabricating bifunctional catalysts with custom-designed heterojunctions and remarkable performance for applications in electrochemical energy devices and related areas.

关键词： Heterojunction Bifunctional catalysts HER OER

Transmission FTIR derivative spectroscopy for estimation of furosemide in raw material and tablet dosage form

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Acta Pharmaceutica Sinica B 2014年第5期4卷 376-383页

作者： Máximo Gallignani Rebeca A.Rondón JoséF.Ovalles María R.Brunetto Laboratorio de Espectroscopia Molecular Departamento de QuímicaFacultad de CienciasUniversidad de Los AndesMérida 5101-AVenezuela Departamento de Análisis y Control Facultad de Farmacia y BioanálisisUniversidad de Los AndesMérida 5101-AVenezuela

A Fourier transform infrared derivative spectroscopy(FTIR-DS)method has been developed for determining furosemide(FUR)in pharmaceutical solid dosage *** method involves the extraction of FUR from tablets with N,N-dimethylformamide by sonication and direct measurement in liquid phase mode using a reduced path length *** general,the spectra were measured in transmission mode and the equipment was configured to collect a spectrum at 4 cm^(-1) resolution and a 13 s collection time(10 scans co-added).The spectra were collected between 1400 cm^(-1) and 450 cm^(-1).Derivative spectroscopy was used for data processing and quantitative measurement using the peak area of the second order spectrum of the major spectral band found at 1165 cm^(-1)(SO_(2) stretching of FUR)with baseline *** method fulfilled most validation requirements in the 2 mg/mL and 20 mg/mL range,with a 0.9998 coefficient of determination obtained by simple calibration model,and a general coefficient of variation <2%.The mean recovery for the proposed assay method resulted within the(100±3)%over the 80%–120% range of the target *** results agree with a pharmacopoeial method and,therefore,could be considered interchangeable.

关键词： FTIR Derivative spectroscopy Furosemide Frusemide Pharmaceutical analysis

Investigating jet physical properties of Fermi blazars with broad-line emissions

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中国科学:物理学、力学、天文学英文版 2023年第10期66卷 138-154页

作者： Lixia Zhang Jianghe Yang Yi Liu Junhui Fan Center for Astrophysics Guangzhou UniversityGuangzhou 51006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Great Bay Center National Astronomical Data CenterGuangzhou 510006China Department of Physics and Electronics Science Hunan University of Arts and ScienceChangde 415000China

Relativistic outflows often exhibit extreme observational characteristics due to beaming effects, which makes measuring their jet power a challenging task. Although the spectral energy distribution(SED) obtained from multi-wavelength data can constrain the physical parameters of these jets, accurately estimating the Doppler factor remains difficult. To address this challenge, we assemble a comprehensive sample containing available SEDs of synchrotron and inverse Compton(IC) components, monochromatic luminosity, and broad-line region(BLR) emissions. We employ a parabolic equation to fit the synchrotron radiation SEDs,constraining jet physical parameters within the framework of a one-zone leptonic model. Our study delves into the jet properties and Doppler factor estimations, yielding the following key findings:(1) The fitting results of SED data for the entire sample reveal normal distributions of jet physical parameters for two subclasses of blazars.(2) Correlation analysis demonstrates that synchrotron peak luminosity exhibits a proportional relationship with both the radio and the γ-ray luminosities.(3) We introduce a novel method for estimating Doppler factors, which uncovers discrepancies between Doppler factors from this work and others from different techniques.

关键词： active galactic nuclei blazars jets spectral energy distribution

Enhanced remediation of Cr(Ⅵ)-contaminated groundwater by coupling electrokinetics with ZVI/Fe_(3)O_(4)/AC-based permeable reactive barrier

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Journal of Environmental Sciences 2022年第2期34卷 280-290页

作者： Ruolin Cao Shiqing Liu Xinyu Yang Chunfeng Wang Yanbin Wang Wanfeng Wang Yunqing Pi Henan Key Laboratory for Environmental Pollution Control and Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control(Ministry of Education) School of EnvironmentHenan Normal UniversityXinxiang 453007China

Although widely used in permeation reaction barrier(PRB)for strengthening the removal of various heavy metals,zero-valent iron(ZVI)is limited by various inherent drawbacks,such as easy passivation and poor electron *** a solution,a synergistic system with PRB and electrokinetics(PRB-EK)was established and applied for the efficient removal of Cr(Ⅵ)-contaminated *** the filling material of PRB,ZVI/Fe_(3)O_(4)/activated carbon(ZVI/Fe_(3)O_(4)/AC)composites were synthesized by ball milling and thermal treatment.A series of continuous flow column experiments and batch tests was conducted to evaluate the removal efficiency of Cr(Ⅵ).Results showed that the removal efficiency of Cr(Ⅵ)remained above 93%even when the bed volume(BV)reached 2000 under the operational parameters(iron/AC mass ratio,2:1;current,5 m A).The mechanism of Cr(Ⅵ)removal by the PRB-EK system was revealed through field emission scanning electron microscopy images,X-ray diffraction,X-ray photoelectron spectroscopy,Fe^(2+) concentration,and redox potential(E h)*** key in Cr(Ⅵ)reduction was the Fe^(2+)/Fe^(3+) cycle driven by the surface microelectrolysis of the *** application of an externally supplied weak direct current maintained the redox process by enhancing the electron transfer capability of the system,thereby prolonging the column ***(Ⅵ)chemical speciation was determined through sequential extraction,verifying the stability and safety of the *** findings provide a scientific basis for PRB design and the in-situ remediation of Cr(Ⅵ)-contaminated groundwater.

关键词： ZVI/Fe_(3)O_(4)/AC Electrokinetics Micro-electrolysis Cr(Ⅵ)-continuous ground water Zero-valent iron