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A Projection Pursuit Dynamic Cluster Model Based on a Memetic Algorithm

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Tsinghua Science and Technology 2015年第6期20卷 661-671页

作者： Hongli Zhang cong wang Wenhui Fan School of Electrical Engineering Xinjiang University Department of Automation Tsinghua University

A Projection Pursuit Dynamic Cluster(PPDC) model optimized by Memetic Algorithm(MA) was proposed to solve the practical problems of nonlinearity and high dimensions of sample data, which appear in the context of evaluation or prediction in complex systems. Projection pursuit theory was used to determine the optimal projection direction; then dynamic clusters and minimal total distance within clusters(min TDc) were used to build a PPDC model. 17 agronomic traits of 19 tomato varieties were evaluated by a PPDC model. The projection direction was optimized by Simulated Annealing(SA) algorithm, Particle Swarm Optimization(PSO), and MA. A PPDC model,based on an MA, avoids the problem of parameter calibration in Projection Pursuit Cluster(PPC) models. Its final results can be output directly, making the cluster results objective and definite. The calculation results show that a PPDC model based on an MA can solve the practical difficulties of nonlinearity and high dimensionality of sample data.

关键词： projection pursuit dynamic cluster memetic algorit

Brazing temperature-dependent interfacial reaction layer features between CBN and Cu-Sn-Ti active filler metal

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Journal of Materials Science & Technology 2019年第10期35卷 2163-2168页

作者： Yonggang Fan Junxiang Fan cong wang School of Metallurgy Northeastern UniversityShenyang110819China Shenyang NEU New Industrial Technology Research Institute Co.LTD Northeastern UniversityShenyang110819China

CBN/Cu-Sn-Ti(CBN: cubic boron nitride) composites are prepared by active brazing sintering at 1123 K,1173 K, 1223 K and 1273 K, respectively. The effects of brazing temperature on the wettability, interfacial characteristics, and elemental distribution variations are fully investigated. When the brazing temperature is below 1223 K, completely uncoated and/or partially coated CBN particles with sharp edges can still be observed, and the reaction layer, mainly composed of Ti N and Ti B2, appears to be thin and *** the brazing temperature is 1223 K, all CBN particles are completely coated, suggesting that adequate wetting has taken place. Besides, as Ti diffuses thoroughly and enriches the interface, the reaction layer, filled primarily by Ti N, Ti B2 and Ti B, becomes thicker(about 1.30 μm), more uniform, stable and continuous. Further increasing the temperature to 1273 K is unnecessary or even harmful as the reaction layer thickness undergoes negligible change yet some tiny micro-cracks appear on the interface, which may likely deteriorate the grinding capability of the final brazing products.

关键词： Brazing temperature CBN/Cu-Sn-Ti filler metal Wettability Reaction layer

Pattern-based learning and control of nonlinear pure-feedback systems with prescribed performance

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Science China(Information Sciences) 2023年第1期66卷 188-209页

作者： Fukai ZHANG Weiming WU cong wang Center for Intelligent Medical Engineering School of Control Science and EngineeringShandong University

This article presents a novel pattern-based intelligent control scheme with prescribed performance(PP) for uncertain pure-feedback systems operating in multiple control situations(patterns). Based on PP,an observer-based adaptive neural network(NN) control approach, which not only achieves system stability and prescribed tracking control performance but also realizes accurate identification/learning of the unknown closed-loop dynamics via deterministic learning and uses only one NN unit, is proposed. Subsequently, the knowledge learned is utilized to construct high-performance candidate controllers for each control *** on the transformed system and observer technique, accurate classification of the nth order systems under different control situations is achieved by requiring only one set of dynamic estimators, thereby significantly reducing the complexity of pattern recognition. Thus, sudden changes in the control situation can be rapidly recognized based on the minimum residual principle, with which the correct candidate controller is selected to achieve superior control performance. The simulation results verify the efficacy of the proposed scheme.

关键词： adaptive neural control (ANC) deterministic learning neural networks (NNs) pattern-based control high gain observer pure-feedback systems

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基于预训练大模型的行动方案生成方法

计算机科学 2025年第1期52卷 80-86页

作者：颜玉松周圆王琮孔圣麒王权黎敏讷王之元国防科技大学计算机学院长沙410005 智能博弈与决策实验室北京100000

围绕生成式人工智能赋能指挥决策需求,分析了指挥决策中方案生成问题的难点挑战和新兴预训练大语言模型技术的应用前景,提出了一种基于预训练大模型的作战行动方案生成方法——COA-Gen。首先,为了使生成的行动方案符合目标,设计了多轮... 详细信息

围绕生成式人工智能赋能指挥决策需求,分析了指挥决策中方案生成问题的难点挑战和新兴预训练大语言模型技术的应用前景,提出了一种基于预训练大模型的作战行动方案生成方法——COA-Gen。首先,为了使生成的行动方案符合目标,设计了多轮方案生成框架;其次,构建了多要素中文提示词模板用于整合海量多源信息;最后,针对特定小领域的数据缺乏问题,引入知识增强技术以提升大模型规划效能。为了验证所提行动方案的效果,制定了基于《星际争霸II》游戏引擎和“虎爪”想定的方案验证环境。实验结果表明,该方法具有较好的鲁棒性,可以较好地依从指挥员意图,验证了大模型用于作战行动方案生成的可行性。此外,不同预训练大模型在相同任务中展现出不同的效果,表明在实际应用中选择不同的预训练大模型可能会生成具有不同风格的行动方案,从而影响最终的行动结果。

关键词：大模型生成式人工智能智能决策指挥与控制作战行动方案

Detailing interfacial reaction layer products between cubic boron nitride and Cu-Sn-Ti active filler metal

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Journal of Materials Science & Technology 2021年第9期68卷 35-39页

作者： Yonggang Fan Junxiang Fan cong wang School of Metallurgy Northeastern UniversityShenyang 110819China

In the present study,we offer an in-depth analysis over the microstructure,thickness and product composition of the interfacial reaction layer generated upon CBN/Cu-Sn-Ti active filler metal at 1223 *** findings demonstrate that adequate wettability and satisfactory bonding have been achieved via chemical reactions between Ti and N,*** importantly,we report,for the first time,the formation of a three-layer juxtaposition of reaction products,namely,TiN,TiB2 and TiB,along the diffusion path of ***,we determine the average layer thickness to be 1.24 μ*** deep etching,we unambiguously present morphologies of the newly formed TiN and TiB2,which are columnar and bulky,re spectively,and constitute the formation of a high strength metallu rgical interfacial bonding layer,and is crucial towards gaining enhanced grinding ***,we propose a possible reaction sequence and mechanism that govern the nucleation and growth of corre s ponding crystals.

关键词： Brazing Cubic boron nitride Cu-Sn-Ti Interfacial products

Controllable Synthesis of Hollow Multishell Structured Co3O4 with Improved Rate Performance and Cyclic Stability for Supercapacitors

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Chemical Research in Chinese Universities 2020年第1期36卷 68-73页

作者： wang cong wang Jiangyan HU Wenping wang Dan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China Department of Chemistry School of Science&Collaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072P.R.China

Hollow multishelled structures(HoMSs)Co3O4 with specially appointed shell number(double-,triple-and quadruple-)were accurately prepared by a sequential templating *** to the superiorities of inimitable porous multishelled structure,triple-HoMSs Co3O4 achieved the best performance among all the samples with a specific capacitance of 1028.9 F/g at 10 mV/s and 688.2 F/g at 0.5 A/g,***,the electrode delivered a high rate performance(89.8%retention at 10 A/g)and excellent cycle stability(6.8%loss over 2000 cycles),showing a great promise for practical application in the future.

关键词： Hollow multishelled structure Cobalt oxide Supercapacitor

Microblog Topic Mining Based on FR-DATM

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Chinese Journal of Electronics 2018年第2期27卷 334-341页

作者： LIU Bingyu wang Cuirong wang Yiran ZHANG Kun wang cong School of information science engineering Northeastern University School of management Northeastern University at Qinhuangdao

Microblog has become a ma jor platform for people to release or obtain information. Texts on Microblog are shorter and have scarce co-occurrence information of terms. It is more complicated to discover topics from Microblog. To solve the problems, this paper proposes a dynamic author topic model FR-DATM and uses Gibbs sampling implementation for inference of this *** FR-DATM model analyzes the relationships between blogs, and connects the related blogs to solve the sparseness of data. It allows blogs to be related to multiple topics,and each author of the blogs is also related to the topics of the blogs. The FR-DATM can also mine the topic evolution of the blogs and the authors. Experiments on Twitter dataset show that FR-DATM outperforms Latent dirichlet allocation(LDA) model and Microblog latent Dirichlet Allocation(MB-LDA) from three different perspectives:The quality of generated latent topics, the model perplexity and FR-DATM can mine the topic that the author are concerned dynamically.

关键词： Topic mining Microblog Dynamic latend topic model Author topic model

Structure and magnetic properties of RAlSi(R=light rare earth)

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Chinese Physics B 2021年第7期30卷 332-338页

作者： Tai wang Yongquan Guo cong wang School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

We prepared the semimetals RAl Si(R=light rare earth),and systematically study their crystal structures and magnetic properties.X-ray diffractions confirm the coexistence of the site-disordered phase with group space of I41/amd and the noncentrosymmetrically ordered phase with space group of I41 md in RAl Si *** ordered phase is the main phase in RAl Si *** Si alloys show nonmagnetic character for R=La,low temperature ferromagnetic order for R=Ce,Pr,and paramagnetic character for R=Nd,*** Al Si shows metamagnetic transition at 10 K and ferromagnetic order at 143 K,*** Al Si follows the van Vleck paramagnetic model in its paramagnetic *** magnetization curves of RAl Si(R=Ce,Pr,Sm)follow the mixed model of ferromagnetism and paramagnetism,and the fitted saturation moment MSdepends on the moment of trivalent rare *** paramagnetic susceptibilityχof RAl Si is going up with increasing the atomic order numbers of rare earth *** reveals that the magnetic property of RAl Si originates from the rare earth.

关键词： RAlSi crystal structure magnetic properties

Post-Impact Motion Planning and Tracking Control for Autonomous Vehicles

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 315-332页

作者： cong wang Zhenpo wang Lei Zhang Huilong Yu Dongpu Cao National Engineering Research Center for Electric Vehicles Beijing Institute of TechnologyBeijing 100081China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Vehicle and Mobility Tsinghua UniversityBeijing 100080China

There is an increasing awareness of the need to reduce traffic accidents and fatality due to vehicle ***-impact hazards can be more serious as the driver may fail to maintain effective control after *** avoid subsequent crash events and to stabilize the vehicle,this paper proposes a post-impact motion planning and stability control method for autonomous *** enabling motion planning method is proposed for post-impact situations by combining the polynomial curve and artificial potential field while considering obstacle avoidance.A hierarchical controller that consists of an upper and a lower controller is then developed to track the planned *** the upper controller,a time-varying linear quadratic regulator is presented to calculate the desired generalized *** the lower controller,a nonlinear-optimization-based torque allocation algorithm is proposed to optimally coordinate the actuators to realize the desired generalized *** proposed scheme is verified under comprehensive driving scenarios through hardware-in-loop tests.

关键词： Active safety Post-impact control Motion planning Vehicle dynamics control