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公共管理艺术价值及提升策略研究

艺术科技 2021年第15期34卷 152-153页

作者：向云龙贵州大学贵州贵阳550025

对政府与民众来讲,公共管理存在一定的艺术价值,公共管理的艺术价值主要是借助公共管理的方式表现的。因此,只有不断对公共管理中的艺术形象进行完美塑造,才能展现艺术价值。

关键词：公共管理艺术价值提升策略

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实时手势与目标检测无人机人机交互系统

福建电脑 2024年第9期40卷 75-79页

作者：向云龙雷德俊许建国荆州学院信息工程学院湖北荆州434020 长江大学文理学院信息与机电工程学院湖北荆州434020

为了提高人机交互效率,本文研发了一种基于视觉的无人机。通过人体手势控制和目标追踪,系统采用Opencv和halcon算子库对无人机拍摄的图像进行处理,结合目标检测模型YOLOv5和Pytorch等算法优化目标检测的实时性和精确度。测试的结果表明... 详细信息

为了提高人机交互效率,本文研发了一种基于视觉的无人机。通过人体手势控制和目标追踪,系统采用Opencv和halcon算子库对无人机拍摄的图像进行处理,结合目标检测模型YOLOv5和Pytorch等算法优化目标检测的实时性和精确度。测试的结果表明,该系统能够准确识别手势并有效执行目标检测,可以广泛应用于安防监控和城市交通管理等领域。

关键词：手势识别目标检测无人机 YOLOv5模型 Halcon算法包

Economic MPC-based transient control for a dual-mode power-split HEV

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Science China(Technological Sciences) 2017年第12期60卷 1917-1934页

作者： QI yunlong WANG WeiDa xiang ChangLe ZHAO YuLong School of Mechanical Engineering Beijing Institute of Technology Beijing100081 China

The existing research into hybrid electric vehicle(HEV) control is mainly focussed on the optimisation of the power distribution between a conventional internal combustion engine(ICE) and an alternative power source(usually a battery pack), however,transient control, which is a key technique that affects both fuel economy and the drivability of the HEV, has not been fully addressed. Especially in dual-mode power-split HE Vs, due to the different dynamic characteristics of the actuators in the transmission, and its complicated speed-torque relationship, transient control also affects the precision of power distribution and the speed of response of the electric output power. To improve the transient control performance, the design of an economic model predictive control(EMPC)-based transient controller for a dual-mode power-split HEV is developed. By incorporating an experimental identification model of a diesel ICE in a control-oriented transmission model, a better coordination among the actuators involved in HEV transmission can be achieved. Moreover, an ICE efficiency index is also added to the objective function to improve ICE fuel efficiency during this transient process. Then, a fast MPC method is applied to reduce the on-line computation effort required of the proposed control algorithm. By the flexible application of the EMPC and an innovative ICE model which is suited to the control-oriented model in EMPC, the transient control performance was improved. The effectiveness,and the real-time performance,of the control algorithm are validated by way of MATLABTM/Simulink-based simulations,as well as test-bed experiments combined with the use of the RapidECU platform.

关键词： hybrid electric vehicle transient control fuel economy economic MPC fast MPC method

MPC-based energy management with adaptive Markov-chain prediction for a dual-mode hybrid electric vehicle

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Science China(Technological Sciences) 2017年第5期60卷 737-748页

作者： xiang ChangLe DING Feng WANG WeiDa HE Wei QI yunlong School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 China

The energy management strategy is an important part of a hybrid electrical vehicle design. It is used to improve fuel economy and to sustain a proper battery state of charge by controlling the power components while satisfying various constraints and driving demands. However, achieving an optimal control performance is challenging due to the nonlinearities of the hybrid powertrain, the time varying constraints, and the dilemma in which controller complexity and real-time capability are generally conflicting objectives. In this paper, a real-time capable cascaded control strategy is proposed for a dual-mode hybrid electric vehicle that considers nonlinearities of the system and complies with all time-varying constraints. The strategy consists of a supervisory controller based on a non-linear model predictive control （MPC） with a long sampling time interval and a coordinating controller based on linear model predictive control with a short sampling time interval to deal with different dynamics of the system. Additionally, a novel data based methodology using adaptive Markov chains to predict future load demand is introduced. The predictive future information is used to improve controller performance. The proposed strategy is implemented on a real test-bed and experimental trials using unknown driving cycles are conducted. The results demonstrate the validity of the proposed approach and show that fuel economy is significantly improved compared with other methods.

关键词： hybrid electric vehicle dual-mode energy management Markov chains model predictive control

A novel ferroelectric based on quinuclidine derivatives

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Chinese Chemical Letters 2020年第6期31卷 1686-1689页

作者： Siyu Deng Junyi Li xiang Chen yunlong Hou Lizhuang Chen School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The compound[(CH3)2 CH-C3 H17 N][CoBr4](1)based on quinuclidine derivatives was achieved by the solution synthetic method and characterized by elemental analysis,infrared spectroscopy,single-crystal X-ray structural analysis and dielectric measurement,***-temperature single-crystal X-ray diffraction suggested that the compound unde rwent the phase transition from the space group C2/c to *** polarization curve was measured using the Sawyer-Tower *** structural phase transitions of 1 was ascribed to the distortion of a[(CH3)2 CH-C3 H17N]2+cation from this inorganicorganic hybrid material[(CH3)2 CH-C3 H17N][CoBr4].The strong change in dielectric anomalies makes compound 1 a suitable candidate for promising switchable dielectric *** work represents a feasible strategy thought for the targeted harvesting of low temperature ferroelectrics.

关键词： Ferroelectric Quinuclidine Phase transition Polarization Dielectric

Research of influence of reduced-order boundary on accuracy and solution of interior points

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Applied Mathematics and Mechanics(English Edition) 2017年第1期38卷 111-124页

作者： yunlong LI Wei CAO Department of Mechanics Tianjin UniversityTianjin 300072China

The flow field with a high order scheme is usually calculated so as to solve complex flow problems and describe the flow structure accurately. However, there are two problems, i.e., the reduced-order boundary is inevitable and the order of the scheme at the discontinuous shock wave contained in the flow field as the supersonic flow field is low. It is questionable whether the reduced-order boundary and the low-order scheme at the shock wave have an effect on the numerical solution and accuracy of the flow field inside. In this paper, according to the actual situation of the direct numerical simulation of the flow field, two model equations with the exact solutions are solved, which are steady and unsteady, respectively, to study the question with a high order scheme at the interior of the domain and the reduced-order method at the boundary and center of the domain. Comparing with the exact solutions, it is found that the effect of reduced-order exists and cannot be ignored. In addition, the other two model equations with the exact solutions, which are often used in fluid mechanics, are also studied with the same process for the reduced-order problem.

关键词： reduced-order boundary shock wave accuracy numerical solution high order scheme

Study of material agglomeration during nozzle injection of multiviscosity liquid into a fluidized bed reactor by the electric conductance method

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Particuology 2018年第3期16卷 174-184页

作者： NingYang yunlong Zhou Tianyu Qi College of Energy Resource and Power Engineering Northeast Dianli University Jilin 132012 China Institute of Unclear and New Energy Technology Tsinghua University Beijing 100084 China

Fluidized bed agglomeration is an important and challenging problem for thermal cracking in fluid cokers. A low coker temperature can be problematic because the bitumen is injected into the fluidized bed with a different viscosity, resulting in formation of agglomerates of varying sizes, which slows the cracking reactions. In the present study, the bed material agglomeration process during nozzle injection of multi- viscosity liquid was investigated in a fluidized bed operated at different mass ratios of the atomization gas to the liquid jets （GLR= 1%-3.5%） and gas velocities （3.9Umf and 5,9Umf） based on a conductance method using a water-sand system to simulate the hot bitumen-coke system at room temperature. During the tests of liquid-jet dispersion throughout the bed, different agglomeration stages are observed at both gas velocities. The critical amount oftert-butanol in the liquid jets that could lead to severe agglomeration of the bed materials （poor fluidization） at GLR = 1% is about 10 wt% at the low fluidizing gas velocity （3.9Umf） and 18wt% at the high gas velocity （5,9Umf）. This study provides a new approach for on-line monitoring of bed agglomeration during liquid injection to guarantee perfect contact between the atomized liquid and the bed particles.

关键词： Material agglomeration Nozzle Multiviscosity Fluidized bed reactor Electric conductance

A thriving decade: rational design, green synthesis, and cutting-edge applications of isoindigo-based conjugated polymers in organic field-effect transistors

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Science China Chemistry 2022年第7期65卷 1225-1264页

作者： Mingliang Zhu yunlong Guo Yunqi Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Recent advances in organic electronics of novel materials and optoelectronic devices spark great interest in the design and synthesis of high-performance polymer semiconductors. During the last decade, isoindigo(ⅡD) and its derivatives have sprung up as common electron-deficient building blocks and obtained extensive applications in organic field-effect transistors(OFETs).In this review, we first present the current status, basic principles, and general material design strategies for OFETs. Then,multiple ⅡD-type acceptors, mature synthetic routes to monomers, and typical ⅡDs-based conjugated polymers are *** also introduce side-chain engineering and cutting-edge applications, like stretchable transistors, sensing, active-matrix driving, etc., of the classic copolymer poly(isoindigo-co-bithiophene). Green polymerization approaches towards conjugated polymers incorporating ⅡDs are subsequently discussed for efficient polymerization. Finally, we conclude this review and propose in-depth prospects with respect to material synthesis and device applications. Undoubtedly, ⅡDs-based conjugated polymers would occupy a significant position in the future of organic electronics, due to diverse building blocks, mature synthetic pathways, tunable side chains, and unique optoelectronic properties.

关键词： isoindigos green synthesis cutting-edge applications polymer field-effect transistors

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Seynergistic effect of Mo and Zr additions on microstructure and mechanical properties of Nb-Ti-Si-based alloys additively manufactured by laser directed energy deposition

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Journal of Materials Science & Technology 2022年第8期103卷 84-97页

作者： yunlong Li Xin Lin yunlong Hu Jun Yu Junguo Zhao Hongbiao Dong Weidong Huang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’an 710072China School of Engineering University of LeicesterLE17RHUK

The synergistic effect of Mo and Zr additions on microstructure evolution,room-temperature fracture toughness and microhardness of Nb-22Ti-15Si-xMo-yZr(x=4,8,y=3,6)alloys manufactured by laser directed energy deposited(L-DED)have been *** major phases in as-deposited 4Mo-3Zr alloy are Nb solid solution(Nbss),Nb_(3)Si andγ-Nb_(5)Si_(3).The Nb_(3)Si phases disappear with increasing Mo content to 8 at.%or increasing Zr content to 6%.γ-Nb_(5)Si_(3) precipitates formed in the Nbss of as-deposited xMo-yZr alloys due to the cyclic re-heating,and theγ-Nb_(5)Si_(3) precipitates and Nbss matrix exhibits orientation relationship(OR)of[001]Nbss//[1112]γand(110)Nbss//(0110)γin as-deposited 4Mo-6Zr *** microstructure of xMo-yZr alloys became relative homogeneity and the Nbss matrix showed the better continuity after the heat treatment(1400°C/30 h).The Nb_(3)Si phase has transformed into Nbss andαNb_(5)Si_(3) with the OR have been determined as{100}Nbss//{100}αand{111}Nbss//{111}αin the heat-treated 4Mo-3Zr *** Mo content increase to 8at.%,a part ofγ-Nb_(5)Si_(3) phase also transformed into theα-Nb_(5)Si_(3) phase with the OR have been determined as{1120}γ//{110}αand{1010}γ//{111}αafter heat *** the as-deposited alloys,the 4Mo-6Zr alloy has the highest fracture toughness KQ with the lowest *** average KQ of 4Mo-6Zr and 8Mo-6Zr alloys increased by 28%and 30%after the heat treatment,and reached 13.61 and 11.43 MPa·m^(1/2),*** hardness of Nb-22Ti-15Si-xMoyZr alloys is significantly decreased after the heat treatment.

关键词： alloys microstructure toughness