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Novel high-safety aeroengine performance predictive control method based on adaptive tracking weight

Chinese Journal of Aeronautics 2024年第7期37卷 352-374页

作者： Qian CHEN Hanlin SHENG jie zhang Jiacheng LI College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Increasing attention has been attracted to the dynamic performance and safety of advanced performance predictive control systems of the next-generation *** latest research demonstrates that Subspace-based Improved Model Predictive Control(SIMPC)can overcome the difficulty in solving the predictive model in MPC/NMPC ***,applying constant design parameters cannot maintain consistent control effects in all ***,the designed system relies too much on sensor-measured data,and thus it is difficult to thoroughly validate the safety of the system because of its high *** means that any potential hardware/software faults will endanger the ***,this paper first presents a novel nonlinear mapping relationship to adaptively tune the tracking weight online with the change of Power Lever Angle(PLA)and real-time relative tracking ***,without introducing additional design parameters,an Adaptive Tracking Weight-based SIMPC(ATW-SIMPC)controller is designed to improve the control performance in all operating states ***,a Primary/Backup Hybrid Control(PBHC)strategy with the ATW-SIMPC controller as the primary system and the traditional speed(Nf)controller as the backup system is proposed to ensure *** designed affiliated switching controller and the real-time monitor therein can be used to realize reasonable and smooth switching between primary/backup systems,so as to avoid bump *** PBHC system switches to the Nf controller when the ATW-SIMPC controller is wrong because of potential hardware/software faults;otherwise,the ATW-SIMPC controller keeps acting on the *** main results prove that the ATW-SIMPC controller with the optimal nonlinear mapping relationship,compared with the existing SIMPC controller,uplifts the dynamic control performance by 32%and reduces overshoots to an allowable limit,resulting in a better control effect in full *** comparison results consistently i

关键词： Aeroengine Model predictive control Hybrid system Adaptive weight Safety

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Effect of biological activated carbon filter depth and backwashing process on transformation of biofilm community

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Frontiers of Environmental Science & Engineering 2019年第1期13卷 159-169页

作者： Wanqi Qi Weiying Li Junpeng zhang Xuan Wu jie zhang Wei zhang College of Environmental Science and Engineering Tongji University Shanghai 200092 China State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Chengdu Chuanli Intelligence Fluid Equipment Co. Ltd. Chengdu 611530 China

The biological activated carbon (BAC) is a popular advanced water treatment to the provision of safe water supply. A bench-scale device was designed to gain a better insight into microbial diversity and community structure of BAC biofilm by using high-throughput sequencing method. Both samples of BAC biofilm (the first, third and fifth month) and water (inlet water and outlet water of carbon filter, outlet water of backwashing) were analyzed to evaluate the impact of carbon filter depth, running time and backwash process. The results showed that the microbial diversity of biofilm decreased generally with the increase of carbon filter depth and biofilm reached a steady-state at the top layer of BAC after three months' running. Proteobacteria (71.02%-95.61%) was found to be dominant bacteria both in biofilms and water samples. As one of opportunistic pathogen, the Pseudomonas aeruginosa in the outlet water of device (1.20%) was about eight times higher than that in the inlet water of device (0.16%) at the genus level after five-month operation. To maintain the safety of drinking water, the backwash used in this test could significantly remove Sphingobacteria (from 8.69% to 5.09%, p < 0.05) of carbon biofilm. After backwashing, the operational taxonomic units (OTUs) number and the Shannon index decreased significantly (p <0.05) at the bottom of carbon column and we found the Proteobacteria increased by about 10% in all biofilm samples from different filter depth. This study reveals the transformation of BAC biofilm with the impact of running time and backwashing.

关键词： Biological activated carbon Biofilm Community structure Carbon filter depth High-throughput sequencing

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Relationship of atmospheric boundary layer depth with thermodynamic processes at the land surface in arid regions of China

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Science China Earth Sciences 2011年第10期54卷 1586-1594页

作者： zhang Qiang zhang jie QIAO Juan WANG Sheng Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province Key Open Laboratory of Arid Climate Change and Disaster Reduction Lanzhou Institute of Arid Meteorology China Meteorological Administration Lanzhou 730020 China Key Laboratory of Meteorological Disasters (KLMD) Ministry of Education Nanjing Information Engineering University Nanjing 210044 China Meteorological Bureau of Xi' an City Xi'an 710016 China Institute of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

The atmospheric boundary layer （ABL） is an important physical characteristic of the Earth＇s atmosphere. Compared with the typical ABL, the ABL in arid regions has distinct features and is formed by particular mechanisms. In this paper, the depth of the diurnal and nocturnal ABLs and their related thermodynamic features of land surface processes, including net radiation, the ground-air temperature difference and sensible heat flux, under typical summer and winter conditions are discussed on the basis of comprehensive observations of the ABL and thermodynamic processes at the land surface carried out in the extreme arid zone of Dunhuang. The relationships of the ABL depth in the development and maintenance stages with these thermodynamic features are also investigated. The results show that the depth of the ABL is closely correlated with the thermodynamic features in both development and maintenance stages and more energy is consumed in the development stage. Further analysis indicates that wind velocity also affects ABL development, especially the development of a stable boundary layer in winter. Taken together, the analysis results indicate that extremely strong thermodynamic processes at the land surface are the main driving factor for the formation of a deep ABL in an arid region.

关键词： arid region deep atmospheric boundary layer development and maintenance thermodynamic process at the land surface main driving factor

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Computer-Assisted Detection of Colonic Polyps Using Improved Faster R-CNN

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Chinese Journal of Electronics 2019年第4期28卷 718-724页

作者： LI Jiangyun zhang jie CHANG Dedan HU Yaojun School of Automation and Electrical Engineering University of Science and Technology Beijing Key Laboratory of Knowledge Automation for Industrial Processes Ministry of Education Department of Gastroenterology Fu Xing Hospital Capital Medical University

The deficiencies of existing polyp detection methods remain: i) They primarily depend on the manually extracted features and require considerable amounts of preprocessing. ii) Most traditional methods cannot specify the location of the polyps in colonoscopy images, especially for the polyps with variable size. In order to derive the improvement and lift the accuracy, we propose a novel and scalable detection algorithm based on deep neural networks—an improved Faster Regionbased Convolutional neural networks(Faster R-CNN)—by increasing the fusion of feature maps at different *** can be employed to detect and locate polyps, and even achieve a multi-object task for polyps in the *** experimental consequences demonstrate that the best version among improved algorithms achieves 97.13%accuracy on the CVC-ClinicDB database, overtaking the previous methods.

关键词： Colonic polyps Deep learning Improved Faster R-CNN Object detection

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Physical simulation of mixing on a C-H2 smelting reduction reactor with different tracer feeding positions

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Journal of Iron and Steel Research International 2020年第9期27卷 1018-1034页

作者： Jin-yin Xie Bo Wang jie-yu zhang State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and EngineeringShanghai UniversityShanghai 200072China

With the growing demand for energy saving,emission reduction,and green metallurgy,we had designed a new C-H2 smelting reduction *** order to solve the key problem that the heat transfer efficiency from high temperature oxidation zone in upper region to low temperature reduction zone in lower region is low in traditional metallurgical reduction reactor,a water simulation was adopted to optimize the mean residence time and to improve the transmission efficiency within the *** to the modified Froude similarity,a water model experimental reactor with a ratio of 1:1 to the prototype was *** the prototype,the feed port was used to feed preheated ore and *** order to simulate the effect of different feeding positions of the tracer on the mixing behavior in the molten pool,four points of tracer feeding position were arranged for a systematic *** the same time,based on double-row side nozzle with thick slag layer in a C-H2 smelting reduction reactor,nine influencing factors,including relative angle between upper and lower side nozzles,were *** experimental results showed that the tracer feeding position had a great influence on the mean residence time,and the relative angle also had a great influence on tracer feeding ***,through comprehensive analysis,the optimal condition parameters were obtained under different tracer feeding *** results provide valuable help for the design and optimization of the C-H2 smelting reduction reactor.

关键词： Smelting reduction reactor Tracer feeding position Double-row side blowing Mean residence time Relative angle Horizontal angle Vertical angle

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Assessment of C-band compact polarimetry SAR for sea ice classification

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Acta Oceanologica Sinica 2016年第5期35卷 79-88页

作者： zhang Xi zhang jie LIU Meijie MENG Junmin First Institute of Oceanography State Oceanic Administration College of Physics Qingdao University

The C-band synthetic aperture radar（SAR） data from the Bohai Sea of China, the Labrador Sea in the Arctic and the Weddell Sea in the Antarctic are used to analyze and discuss the sea ice full polarimetric information reconstruction ability under compact polarimetric modes. The type of compact polarimetric mode which has the highest reconstructed accuracy is analyzed, along with the performance impact of the reconstructed pseudo quad-pol SAR data on the sea ice detection and sea ice classification. According to the assessment and analysis, it is recommended to adopt the CTLR mode for reconstructing the polarimetric parameters σ_（HH）~0,σ_（VV）~0, H and α,while for reconstructing the polarimetric parameters σ_（HV）~0, ρ_（H-V）, λ_1 and λ_2, it is recommended to use the π/4 ***, it is recommended to use the π/4 mode in studying the action effects between the electromagnetic waves and sea ice, but it is recommended to use the CTLR mode for studying the sea ice classification.

关键词： sea ice SAR compact polarimetry sea ice classification assessment and analysis

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Bi-level Optimal Operation Model of Mobile Energy Storage System in Coupled Transportation-power Networks

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1725-1737页

作者： Weiqing Sun Wei Liu jie zhang Kunpeng Tian School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China

The operation characteristics of energy storage can help the distribution network absorb more renewable energy while improving the safety and economy of the power *** energy storage systems(MESSs)have a broad application market compared with stationary energy storage systems and electric vehicles due to their flexible mobility and good dispatch ***,when urban traffic flows rise,the congested traffic environment will prolong the transit time of MESS,which will ultimately affect the operation state of the power networks and the economic benefits of *** paper proposes a bi-level optimization model for the economic operation of MESS in coupled transportation-power networks,considering road congestion and the operation constraints of the power *** upper-level model depicts the daily operation scheme of MESS devised by the distribution network operator(DNO)in order to maximize the total revenue of the *** fuzzy time windows and fuzzy road congestion indexes,the lower-level model optimizes the route for the transit problem of ***,road congestion that affects the transit time of MESS can be fully incorporated in the optimal operation *** the IEEE 33-bus distribution network and the 29-node transportation network are used to verify and examine the effectiveness of the proposed *** simulation results demonstrate that the operation scheme of MESS will avoid the congestion period when considering road ***,the transit energy consumption and the impact of the traffic environment on the economic benefits of MESS can be reduced.

关键词： Mobile energy storage system economic dispatch bi-level optimization model road congestion fuzzy constraint

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Dynamic modeling and beating phenomenon analysis of space robots with continuum manipulators

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Chinese Journal of Aeronautics 2022年第9期35卷 226-241页

作者： Jinzhao YANG Haijun PENG jie zhang Zhigang WU School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China Department of Engineering Mechanics Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian I16024China

Space robotics has been used extensively in complex space missions. Rigid-manipulator space robots may suffer from rigid-body collisions with targets. This collision is likely to cause damage to the space robot and the target. To overcome such a problem, a novel ContinuumManipulator Space Robot(CMSR) for performing on-orbit servicing missions is proposed in this paper. Compared with rigid-manipulator space robots, CMSRs are able to perform compliant operations and avoid rigid-body collisions with a target. The CMSR consists of two kinds of flexible components, including solar arrays and continuum manipulators. The elastic vibrations of these flexible components disturb the position and attitude of CMSRs. The beating phenomenon introduced by the energy transfer among these flexible components can cause damage to solar *** complicated dynamic coupling poses enormous challenges in dynamic modeling and vibration analysis. The dynamic model for CMSRs is derived and the mechanism of the beating phenomenon is analyzed in this paper. Simulation results show that an obvious beating phenomenon occurs and the amplitude of the solar arrays increases significantly when the natural frequencies of two kinds of flexible components are close. A method is provided to avoid the beating phenomenon.

关键词： Continuum manipulators Dynamic model Solar arrays Space robots Vibration analysis

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Generalized Energy Storage Allocation Strategies for Load Aggregator in Hierarchical Electricity Markets

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 1021-1031页

作者： Weiqing Sun Wei Liu Wei Xiang jie zhang School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Shenergy New Power Storage R&D Co. Ltd.Shanghai 201419China

The uncertainty of user-side resource response will affect the response quality and economic benefit of load aggregator(LA).Therefore,this paper regards the flexible user-side resources as a virtual energy storage(VES),and uses the traditional narrow sense energy storage(NSES)to alleviate the uncertainty of *** order to further enhance the competitive advantage of LA in electricity market transactions,the operation mechanism of LA in day-ahead and real-time market is analyzed,***,truncated normal distribution is used to simulate the response accuracy of VES,and the response model of NSES is constructed at the same ***,the hierarchical market access index(HMAI)is introduced to quantify the risk of LA being eliminated in the market ***,combined with the priority response strategy of VES and HMAI,the capacity allocation model of NSES is *** the capacity model is nonlinear,Monte Carlo simulation and adaptive particle swarm optimization algorithm are used to solve *** order to verify the effectiveness of the model,the data from PJM market in the United States is used for *** results show that the model established can provide the effective NSES capacity allocation strategy for LA to compensate the uncertainty of VES response,and the economic benefit of LA can be increased by 52.2%at its *** the reasonable NSES capacity allocation,LA is encouraged to improve its own resource level,thus forming a virtuous circle of market competition.

关键词： Load aggregator generalized energy storage narrow sense energy storage capacity allocation strategy ancillary service market

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Pose-free assembly retrieval based on spatial-contact skeleton

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Chinese Journal of Aeronautics 2022年第4期35卷 497-507页

作者： Jianfeng YU Jiazhen PANG jie zhang Yuan LI School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China

In complicated product industry such as aircraft manufacturing, an assembly model contains abundant engineering information for use in design, manufacture, and maintenance. Assembly retrieval can be used to find relevant models for knowledge reuse. However, an assembly with rotatable joints may have many poses, which brings difficulty to assembly retrieval, since there is no pose principle for assembly design. Therefore, focused on rotatable joints in assembly, a skeleton-based descriptor for pose-free assembly retrieval is proposed. The centroid points of part surfaces and contact faces in an assembly are extracted to construct a spatial-contact skeleton. The skeletonbased distance is proposed to measure the distance between two surface points, which is invariant to the rotatable joints. The distribution of skeleton distances between two parts is used to describe the pair. Considering a part paired with all other parts in the assembly, the set of part pairs is used to represent a part, and the modified Hausdorff distance is used to measure the dissimilarity between parts for assembly retrieval. Experiments are conducted to compare the accuracy of the proposed descriptor to holistic and structureless descriptors. The proposed method is shown to retrieve assemblies with similar parts and structures regardless of their rotatable joints.

关键词： Assembly retrieval Computer-aided design(CAD) Rotation connection Similarity measure Spatial-contact skeleton

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