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Neural decoding based on probabilistic neural network

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第4期11卷 298-306页

作者： Yi YU shao-min zhang Huai-jian zhang Xiao-chun LIU Qiao-sheng zhang Xiao-xiang ZHENG Jian-hua DAI Qiushi Academy for Advanced Studies Zhejiang University Hangzhou 310027 China College of Biomedical Engineering and Instrument Science Zhejiang University Hangzhou 31002 7 China Key Laboratory of Biomedical Engineering of ministry of Education Zhejiang University Hangzhou 310027 China College of Computer Science and Technology Zhejiang University Hangzhou 310027 China

Brain-machine interface (BMI) has been developed due to its possibility to cure severe body paralysis. This technology has been used to realize the direct control of prosthetic devices,such as robot arms,computer cursors,and paralyzed muscles. A variety of neural decoding algorithms have been designed to explore relationships between neural activities and movements of the limbs. In this paper,two novel neural decoding methods based on probabilistic neural network (PNN) in rats were introduced,the PNN decoder and the modified PNN (MPNN) decoder. In the ex-periment,rats were trained to obtain water by pressing a lever over a pressure threshold. Microelectrode array was implanted in the motor cortex to record neural activity,and pressure was recorded by a pressure sensor synchronously. After training,the pressure values were estimated from the neural signals by PNN and MPNN decoders. Their per-formances were evaluated by a correlation coefficient (CC) and a mean square error (MSE). The results show that the MPNN decoder,with a CC of 0.8657 and an MSE of 0.2563,outperformed the traditionally-used Wiener filter (WF) and Kalman filter (KF) decoders. It was also observed that the discretization level did not affect the MPNN performance,indicating that the MPNN decoder can handle different tasks in BMI system,including the detection of movement states and estimation of continuous kinematic parameters.

关键词： Brain-machine interfaces (BMI) Neural decoding Probabilistic neural network (PNN) Microelectrode array

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Genetic mechanisms of secondary pore development zones of Es_4~x in the north zone of the minfeng Sag in the Dongying Depression,East China

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Petroleum Science 2016年第1期13卷 1-17页

作者： Yan-Zhong Wang Ying-Chang Cao shao-min zhang Fu-Lai Li Fan-Chao Meng School of Geosciences China University of Petroleum

The genetic mechanisms of the secondary pore development zones in the lower part of the fourth member of the Shahejie Formation（Es_4／6x） were studied based on core observations,petrographic analysis,fluid inclusion analysis,and petrophysical measurements along with knowledge of the tectonic evolution history,organic matter thermal evolution,and hydrocarbon accumulation *** secondary pore development zones exist in Es_4~x,the depths of which range from 4200 to 4500 m and from 4700 to 4900 m,*** reservoirs in these zones mainly consist of conglomerate in the middle fan braided channels of nearshore subaqueous fans,and the secondary pores in these reservoirs primarily originated from the dissolution of feldspars and carbonate *** reservoirs experienced ‘‘alkaline–acidic–alkaline–acidic–weak acidic＇＇,‘‘normal pressure–overpressure–normal pressure＇＇,and‘‘formation temperature increasing–decreasing–increasing＇＇ diagenetic *** diagenetic evolution sequences were ‘‘compaction/gypsum cementation/halite cementation/pyrite cementation/siderite cementation–feldspar dissolution/quartz overgrowth–carbonate cementation/quartz dissolution/feldspar overgrowth–carbonate dissolution/feldspar dissolution/quartz overgrowth–pyrite cementation and asphalt filling＇＇.Many secondary pores（fewer than the number of primary pores） were formed by feldspar dissolution during early acidic geochemical systems with organic acid when the burial depth of the reservoirs was relatively ***,the pore spaces wereslightly changed because of protection from early hydrocarbon charging and fluid overpressure during deep ***,the present secondary pore development zones were formed when many primary pores were filled by asphalt and pyrite from oil cracking in deeply buried paleoreservoirs.

关键词： reservoirs dissolution Depression carbonate hydrocarbon pores quartz porosity buried pyrite

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Influence of fuel quality on vehicular NOx emissions

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Journal of Environmental Sciences 2001年第3期13卷 265-271页

作者： WANG shao xia, shao min, zhang Yuan hang (State Joint Key Laboratory of Environmental Simulation and Pollution Control, Center for Environmental Sciences, Peking University, Beijing 100871, China. State Joint Key Laboratory of Environmental Simulation and Pollution Control Center for Environmental Sciences Peking University Beijing 100871 China

The quality of gasoline and diesel fuel affects pollutant emissions from vehicles. By applying the COMPLEX model, developed by the US EPA and industry to relate fuel composition to vehicle emissions, this paper estimates the influence of improvements in gasoline quality to lower vehicular NOx emissions. A case study is performed for Guangzhou City that has NOx concentrations significantly above the national ambient air quality standards (NAAQS). The paper discusses the potential for reducing NOx in Guangzhou by improving the quality of gasoline.

关键词： Air quality Automotive fuels Gasoline

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Reservoir characteristics,formation mechanisms and petroleum exploration potential of volcanic rocks in China

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Petroleum Science 2015年第1期12卷 54-66页

作者： Zhi-Guo Mao Ru-Kai Zhu Jing-Lan Luo Jing-Hong Wang Zhan-Hai Du Ling Su shao-min zhang Research Institute of Petroleum Exploration & Development Petro China State Key Laboratory of Enhanced Oil Recovery Northwest University Xi’an 710069 State Key Laboratory of Continental Dynamics International Iraq FZE Petro China China University of Petroleum

Characterized by complex lithology and strong heterogeneity, volcanic reservoirs in China developed three reservoir space types： primary pores, secondary pores and fractures. The formation of reservoir space went through the cooling and solidification stage （including blast fragmentation, crystallization differentiation and solidification） and the epidiagenesis stage （including metasomatism, filling, weathering and leaching, formation fluid dissolution and tectonism）. Primary pores were formed at the solidification stage, which laid the foundation for the development and transformation of effective reservoirs. Secondary pores were formed at the epidiagenesis stage, with key factors as weathering and leaching, formation fluid dissolution and tectonism. In China, Mesozoic-Cenozoic volcanic rocks developed in the Songliao Basin and Bohai Bay Basin in the east and Late Paleozoic volcanic rocks developed in the Junggar Basin, Santanghu Basin and Ta- rim Basin in the west. There are primary volcanic reser- voirs and secondary volcanic reservoirs in these volcanic rocks, which have good accumulation conditions and great exploration potential.

关键词： Volcanic reservoirs Diagenesis Formation mechanism Hydrocarbon exploration

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Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China Chemistry 2024年第6期67卷 1935-1940页

作者： Ya-Ping shao Zhuo-min Chi Yong-min Liang State Key Laboratory of Applied Organic Chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking

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Tackling the proton limit under industrial electrochemical CO_(2)reduction by a local proton shuttle

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Carbon Energy 2024年第4期6卷 233-243页

作者： Tianye shao Kang Yang Sheng Chen min Zheng Ying zhang Qiang Li Jingjing Duan MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjingChina School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSouth AustraliaAustralia

Industrial CO_(2)electroreduction has received tremendous attentions for resolution of the current energy and environmental crisis,but its performance is greatly limited by mass transport at high current *** this work,an ion‐polymer‐modified gas‐diffusion electrode is used to tackle this proton *** is found that gas diffusion electrode‐Nafion shows an impressive performance of 75.2%Faradaic efficiency in multicarbon products at an industrial current density of 1.16 A/cm^(2).Significantly,in‐depth electrochemical characterizations combined with in situ Raman have been used to determine the full workflow of protons,and it is found that HCO_(3)^(−)acts as a proton pool near the reaction environment,and HCO_(3)^(−)and H_(3)O^(+)are local proton donors that interact with the proton shuttle−SO_(3)^(−)from *** rich proton hopping sites that decrease the activation energy,a“Grotthuss”mechanism for proton transport in the above system has been identified rather than the“Vehicle”mechanism with a higher energy ***,this work could be very useful in terms of the achievement of industrial CO_(2)reduction fundamentally and practically.

关键词： industrial CO_(2)electroreduction proton donor proton pool proton shuttle proton transport mechanism

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Neural network modeling and prediction of HfO2 thin film properties tuned by thermal annealing

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High Power Laser Science and Engineering 2024年第2期12卷 79-86页

作者： min Gao Chaoyi Yin Jianda shao Meiping Zhu School of Microelectronics Shanghai UniversityShanghaiChina Laboratory of Thin Film Optics Key Laboratory of Materials for High Power LaserShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhouChina

Plasma-enhanced atomic layer deposition (PEALD) is gaining interest in thin films for laser applications, and post-annealing treatments are often used to improve thin film properties. However, research to improve thin film properties is often based on an expensive and time-consuming trial-and-error process. In this study, PEALD-HfO2 thin film samples were deposited and treated under different annealing atmospheres and temperatures. The samples were characterized in terms of their refractive indices, layer thicknesses and O/Hf ratios. The collected data were split into training and validation sets and fed to multiple back-propagation neural networks with different hidden layers to determine the best way to construct the process–performance relationship. The results showed that the three-hidden-layer back-propagation neural network (THL-BPNN) achieved stable and accurate fitting. For the refractive index, layer thickness and O/Hf ratio, the THL-BPNN model achieved accuracy values of 0.99, 0.94 and 0.94, respectively, on the training set and 0.99, 0.91 and 0.90, respectively, on the validation set. The THL-BPNN model was further used to predict the laser-induced damage threshold of PEALD-HfO2 thin films and the properties of the PEALD-SiO2 thin films, both showing high accuracy. This study not only provides quantitative guidance for the improvement of thin film properties but also proposes a general model that can be applied to predict the properties of different types of laser thin films, saving experimental costs for process optimization.

关键词： laser-induced damage threshold laser thin film neural network plasma-enhanced atomic layer deposition

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Factors influencing physical property evolution in sandstone mechanical compaction:the evidence from diagenetic simulation experiments

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Petroleum Science 2015年第3期12卷 391-405页

作者： Ke-Lai Xi Ying-Chang Cao Yan-Zhong Wang Qing-Qing zhang Jie-Hua Jin Ru-Kai Zhu shao-min zhang Jian Wang Tian Yang Liang-Hui Du School of Geosciences China University of Petroleum Department of Geosciences University of Oslo Research Institute of Petroleum Exploration and Development CNPC

In order to analyze the factors influencing sandstone mechanical compaction and its physical property evolution during compaction processes, simulation exper- iments on sandstone mechanical compaction were carried out with a self-designed diagenetic simulation system. The experimental materials were modem sediments from dif- ferent sources, and the experiments were conducted under high temperature and high pressure. Results of the exper- iments show a binary function relation between primary porosity and mean size as well as sorting. With increasing overburden pressure during mechanical compaction, the evolution of porosity and permeability can be divided into rapid compaction at an early stage and slow compaction at a late stage, and the dividing pressure value of the two stages is about 12 MPa and the corresponding depth is about 600 m. In the slow compaction stage, there is a good exponential relationship between porosity and overburden pressure, while a good power function relationship exists between permeability and overburden pressure. There is also a good exponential relationship between porosity and permeability. The influence of particle size on sandstone mechanical compaction is mainly reflected in the slowcompaction stage, and the influence of sorting is mainly reflected in the rapid compaction stage. Abnormally high pressure effectively inhibits sandstone mechanical com- paction, and its control on sandstone mechanical com- paction is stronger than that of particle size and sorting. The influence of burial time on sandstone mechanical compaction is mainly in the slow compaction stage, and the porosity reduction caused by compaction is mainly con- trolled by average particle size.

关键词： Primary porosity Mechanical compaction Unconsolidated sand Diagenetic simulation experiment

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Influences of Co-Flow and Counter-Flow Modes of Reactant Flow Arrangement on a PEMFC at Start-Up

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1337-1356页

作者： Qianqian shao min Wang Nuo Xu School of Petroleum Engineering Guangdong University of Petrochemical TechnologyMaoming525000China Mechanics Division Beijing Computational Science Research CenterBeijing100193China

To investigate the influences of co-flowand counter-flowmodes of reactant flowarrangement on a proton exchange membrane fuel cell(PEMFC)during start-up,unsteady physical and mathematical models fully coupling the flow,heat,and electrochemical reactions in a PEMFC are *** continuity equation and momentum equation are solved by handling pressure-velocity coupling using the SIMPLE *** electrochemical reaction rates in the catalyst layers(CLs)of the cathode and anode are calculated using the Butler-Volmer *** multiphase mixture model describes the multiphase transport process of gas mixtures and liquid water in the fuel *** validation,the influences of co-flow and counter-flow modes on the PEMFC performance are investigated,including the evolution of the current density,flow field,temperature field,and reactant concentration field during start-up,as well as the steady distribution of the current density,reactant concentration,andmembrane water content when the start-up ***-flow and counter-flow modes influence the current density distribution and temperature *** the one hand,the co-flow mode accelerates the start-up process of the PEMFC and leads to a more evenly distributed current density than the counter-flow *** the other hand,the temperature difference between the inlet and outlet sections of the cell is up to 10.1℃ under the co-flow mode,much larger than the 5.0℃ observed in the counter-flow ***,the counter-flowmode results in a more evenly distributed temperature and a lower maximum temperature than the co-flow ***,in the flow field design of a PEMFC,the reactant flow arrangements can be considered to weigh between better heat management and higher current density distribution of the cell.

关键词： PEMFC full coupling model Butler-Volmer equation multiphase mixture model co-flow mode counter-flow mode

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Elliptical encirclement control capable of reinforcing performances for UAVs around a dynamic target

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Defence Technology（防务技术） 2024年第2期32卷 104-119页

作者： Fei zhang Xingling shao Yi Xia Wendong zhang National Key Laboratory for Electronic Measurement Technology School of Instrument and ElectronicsNorth University of ChinaTaiyuan030051China

Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external ***,elliptical encirclement with a time-varying observation radius,may permit a more flexible and high-efficacy enclosing solution,whilst the non-orthogonal property between axial and tangential speed components,non-ignorable environmental perturbations,and strict assignment requirements empower elliptical encircling control to be more challenging,and the relevant investigations are still *** this line,an appointed-time elliptical encircling control rule capable of reinforcing circumnavigation performances is developed to enable Unmanned Aerial Vehicles(UAVs)to move along a specified elliptical path within a predetermined reaching *** remarkable merits of the designed strategy are that the relative distance controlling error can be guaranteed to evolve within specified regions with a designer-specified convergence ***,wind perturbations can be online counteracted based on an unknown system dynamics estimator(USDE)with only one regulating parameter and high computational *** tool demonstrates that all involved error variables are ultimately limited,and simulations are implemented to confirm the usability of the suggested control algorithm.

关键词： Elliptical encirclement Reinforced performances Wind perturbations UAVs

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