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Joint Algorithm of Message Fragmentation and No-Wait Scheduling for Time-Sensitive Networks

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 478-490页

作者： Xi Jin Changqing xia nan Guan Peng Zeng Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016 Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China Department of Computing Hong Kong Polytechnic UniversityHong KongChina

Time-sensitive networks(TSNs)support not only traditional best-effort communications but also deterministic communications,which send each packet at a deterministic time so that the data transmissions of networked control systems can be precisely scheduled to guarantee hard real-time ***-wait scheduling is suitable for such TSNs and generates the schedules of deterministic communications with the minimal network resources so that all of the remaining resources can be used to improve the throughput of best-effort ***,due to inappropriate message fragmentation,the realtime performance of no-wait scheduling algorithms is ***,in this paper,joint algorithms of message fragmentation and no-wait scheduling are ***,a specification for the joint problem based on optimization modulo theories is proposed so that off-the-shelf solvers can be used to find optimal ***,to improve the scalability of our algorithm,the worst-case delay of messages is analyzed,and then,based on the analysis,a heuristic algorithm is proposed to construct low-delay ***,we conduct extensive test cases to evaluate our proposed *** evaluation results indicate that,compared to existing algorithms,the proposed joint algorithm improves schedulability by up to 50%.

关键词： Message fragmentation networked control system real-time scheduling time sensitive network

二维光晶格中旋转玻色-爱因斯坦凝聚基态中的涡旋分布

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原子与分子物理学报 2025年第1期42卷 118-126页

作者：张志强王平平吕亚南郑州商学院大学物理教研室郑州451200

利用多重网格预条件共轭梯度法,研究了囚禁在二维光晶格与谐振势组成的复合势阱中的旋转玻色-爱因斯坦凝聚体中的涡旋分布,探讨了光晶格深度、晶格常数和凝聚体旋转频率对旋转凝聚体中涡旋分布的影响.结果表明,由于光晶格势阱的引入,凝... 详细信息

利用多重网格预条件共轭梯度法,研究了囚禁在二维光晶格与谐振势组成的复合势阱中的旋转玻色-爱因斯坦凝聚体中的涡旋分布,探讨了光晶格深度、晶格常数和凝聚体旋转频率对旋转凝聚体中涡旋分布的影响.结果表明,由于光晶格势阱的引入,凝聚体中产生涡旋,且涡旋位于外部势阱极小值处.随着光晶格势阱深度的增加,凝聚体集聚在光晶格势阱的底部,形成格点状分布,其中的涡旋形成涡旋对,并融合形成更大的涡旋.在晶格常数较小时,凝聚体中涡旋分布形成类似Abrikosov涡旋晶格,随着晶格常数的增加,凝聚体中涡旋的分布形式出现多样化,出现了内中外三层结构.随着旋转频率的增加,凝聚体中涡旋数目也随之增加,涡旋分布也更加复杂和富于变化,凝聚体密度分布范围也随着旋转频率的增加而扩展.当凝聚体旋转频率接近外部谐振势阱的谐振频率,即凝聚体处于最低朗道能级近似时,其中的涡旋数量大幅度增加,且出现涡旋成对组合与融合现象,并形成了涡旋斑图花纹.

关键词：波色-爱因斯坦凝聚涡旋二维光晶格复合势阱

基于Res-UNet网络的井地电阻率法反演

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物探与化探 2025年第1期49卷 73-81页

作者：周楠王智方思南张宇哲长江大学电子信息与电气工程学院湖北荆州434023 长江大学地球物理与石油资源学院湖北武汉430100

为了解决传统电阻率反演方法依赖反演初始模型的选择、反演过程容易陷入局部极小且反演耗时较长的缺点,本文提出了一种基于Res-UNet神经网络的井地电阻率实时反演方法,通过Gmsh软件获得大幅扩展的正演响应数据集,并针对数据特性选取合... 详细信息

为了解决传统电阻率反演方法依赖反演初始模型的选择、反演过程容易陷入局部极小且反演耗时较长的缺点,本文提出了一种基于Res-UNet神经网络的井地电阻率实时反演方法,通过Gmsh软件获得大幅扩展的正演响应数据集,并针对数据特性选取合适的网络参数进行反演实验。实验结果表明,Res-UNet算法能充分挖掘数据特性,快速获得符合地层电性特征的电阻率成像结果,在电阻率正演数据集上的预测值和正演响应的均方误差为0.01944,在测试集上的均方根误差为0.0758,与传统反演方法相比,成像结果有显著提升。基于Res-UNet网络的井地电阻率反演方法在仿真模型的反演计算中得到了较好的结果,能快速、准确地反演出地下异常体的位置和形态,且具有较好的抗噪声能力,为电阻率数据和真实地电结构之间的映射关系提供了一种新的方法和思路。

关键词： Res-UNet Gmsh 残差块批量建模井地电阻率反演

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明代嘉鱼李憭与四邑公堤修筑始末考

湖北科技学院学报 2025年第1期45卷 10-18页

作者：朱志先张霞湖北科技学院人文与传媒学院湖北咸宁437100

从宋代开始,为解决长江水对江夏、嘉鱼、咸宁、蒲圻四地沿江造成的水患,四地主政者不断修筑江堤,各地利害关系不一,所修江堤效果不太理想。明代万历年间,在嘉鱼李憭的呼吁协调下,历时数年,加固老堤,修筑新堤,长达上百里,被誉为四邑公堤... 详细信息

从宋代开始,为解决长江水对江夏、嘉鱼、咸宁、蒲圻四地沿江造成的水患,四地主政者不断修筑江堤,各地利害关系不一,所修江堤效果不太理想。明代万历年间,在嘉鱼李憭的呼吁协调下,历时数年,加固老堤,修筑新堤,长达上百里,被誉为四邑公堤,有效抵制了江水泛滥所造成的危害。其间,李憭在四邑公堤的修筑筹备方面积极倡导和协调,在修筑制度方面采取因地制宜灵活变通的措施,在修筑经费方面据实情合理估算费用,保证四邑公堤顺利完工。

关键词：明代嘉鱼李憭四邑公堤水利

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Reduction of dinitrogen to ammonia on doped three-atom clusters Nb_(2)M(M=Sc to Cu & Y to Ag)

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Rare Metals 2024年第8期43卷 3810-3818页

作者： Ran Cheng Chao-nan Cui zhi-Xun Luo Beijing National Laboratory for Molecular Science(BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Science University of Chinese Academy of SciencesBeijing 100049China

Catalytic reduction of dinitrogen to ammonia under mild conditions remains an attractive topic for the purpose of lowering energy ***-atom metal clusters have been proved an ideal model to explore highly efficient catalysts taking advantage of unique geometric/electronic structures and cooperative active *** a study of N2 activation and reduction on seventeen bimetallic Nb_2M(M=Sc to Cu,and Y to Ag) clusters was *** key processes for ammonia fixation(namely nitrogen activation,hydrogenation,and ammonia desorption) are fully studied,and three preferred systems(Nb_2Ni,Nb_2Rh and Nb_2Pd) are highlighted with outstanding catalytic *** d-σ and d-π~* orbital hybridizations between these metal clusters and N_(2) were demonstrated and the internal association with the N≡N bond activation was *** examining the ammonia synthesis on four chosen Nb_(2)M clusters(M=Fe,Ni,Rh and Pd),it can be elucidated that the distal pathway is more favorable than the alternative pathway in these *** work not only clarifies the N_(2) reduction on the bimetallic Nb_(2)M clusters,but also guides efficient bimetallic catalyst design.

关键词： Three-atom cluster catalysis Three-criteria strategy Nitrogen fixation Ammonia synthesis Theoretical calculations

Modification of methyl oleate for silicon-based biological lubricating base oil

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Chinese Journal of Chemical Engineering 2017年第1期25卷 130-136页

作者： Shixing Cui zhi Yun xia Gui College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China

A new kind of silicon-based biological lubricating base oil with good viscosity-temperature behavior,viscosity index,thermostability,oxidation stability and wear resistance performance was synthesized as a derivative of methyl *** reaction was introduced to further improve methyl oleate oxidation stability and lubricity after epoxidation and open-ring *** order of effectiveness of acid binding agent was N,N-diisopropylethylamine(DIEA) > pyridine > diethylamine > triethylamine,and the effects of various parameters on the trimethylsilylation reaction as well as on the silicon-oxygen bond stability and reaction yield were studied.A maximum yield of 34.54%was achieved at hydroxyl/trimethyl chlorosilane/DIEA molar ratio of1:1.25:1,reaction temperature 40℃,reaction time 1.5 h.

关键词： Methyl oleate Trimethyl chlorosilane Acid binding agent N N-diisopropylethylamine Lubricity Silicon-based biological lubricating base oil

Continuous production of biodiesel from cottonseed oil and methanol using a column reactor packed with calcined sodium silicate base catalyst

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Chinese Journal of Chemical Engineering 2016年第4期24卷 499-505页

作者： xia Gui Sichen Chen zhi Yun College of Chemistry and Chemical Engineering Nanjing Tech University

Sodium silicate and that calcined at 400℃ for 2 h were used to catalyze the transesterification of cottonseed oil with methanol. Calcined sodium silicate （CSS） catalyst exhibited much higher catalytic activity and stability. A maximum biodiesel yield of 98.9~ was achieved at methanol/oil mole ratio of 12：1, reaction temperature 65℃, reaction time 3.0 h, and CSS/oil mass ratio of 2 Wffo. After 7 consecutive reactions without any treatment, biodiesel yield reduced to 82.5%. Considering technological and economic feasibility, CSS base catalyst supported on 0 rings was prepared for continuous transesterification. The maximum yield was 99.1% under optimum conditions （reaction temperature 55 ~C, methanol velocity 1 ml. rain- 1, oil velocity 3 ml- rain- 1, and 5 tower sec- tions）. These results indicate that this new continuous biodiesel production process and apparatus present a great potential for industrial application in biodiesel.

关键词： TransesterificationCottonseed oilCalcined sodium silicateBiodieselSodium silicateContinuous production

A Train-Bridge Dynamic Interaction Analysis Method and Its Experimental Validation

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Engineering 2016年第4期2卷 528-536页

作者： nan Zhang Yuan Tian He xia School of Civil Engineering BeijingJiaotong University Beijing 100044 China

The train-bridge dynamic interaction problem began with the development of railway technology, and requires an evaluation method for bridge design in order to ensure the safety and stability of the bridge and the running train. This problem is studied using theoretical analysis, numerical simulation, and experimental study. In the train-bridge dynamic interaction system proposed in this paper, the train vehicle model is established by the rigid-body dynamics method, the bridge model is established by the finite element method, and the wheel/rail vertical and lateral interaction are simulated by the corresponding assumption and the Kalker linear creep theory, respectively. Track irregularity, structure deformation, wind load, collision load, structural damage, foundation scouring, and earthquake action are regarded as the excitation for the system. The train-bridge dynamic interaction system is solved by inter-history iteration. A case study of the dynamic response of a CRH380BL high-speed train running through a standard-design bridge in China is discussed. The dynamic responses of the vehicle and of the bridge subsystems are obtained for speeds ranging from 200 km-b-1 to 400 km.h-1, and the vibration mechanism are analyzed.

关键词： Train-bridge dynamic interaction Wheel/rail relationship Inter-history iteration Field measurement Experimental validation

Sulfur dioxide gas sensing at room temperature based on tin selenium/tin dioxide hybrid prepared via hydrothermal and surface oxidation treatment

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Rare Metals 2021年第6期40卷 1588-1596页

作者： Qian-nan Pan zhi-Min Yang Wei-Wei Wang Dong-zhi Zhang College of Control Science and Engineering China University of Petroleum(East China)Qingdao 266580China

In this paper,a novel SnSe/SnO_(2) nanoparticles(NPs) composite has been successfully fabricated through hydrothermal method and surface oxidation *** as-prepared sample was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS) and transmission electron microscopy(TEM).A series of morphological and structural characteristics confirm that the SnSe/SnO_(2) NPs composite shows a core-shell structure with a SnO_(2) shell with thickness of 6 *** prepared SnO_(2) NPs and SnSe/SnO_(2) NPs composite were applied as gas-sensing materials,and their gas-sensing properties were investigated at room temperature *** results show that the response value of the SnSe/SnO_(2) composite sensor toward 100×10^(-6) SO_(2) is 15.15%,which is 1.32 times higher than that of pristine SnSe(11.43%).And the SnSe/SnO_(2) composite sensor also has a detection limit as low as 74×10^(-9) and an ultra-fast response *** enhanced gas-sensing performance is attributed to the formation of p-n heterojunction between SnSe and SnO_(2) and the appropriate SnO_(2) shell thickness.

关键词： SO_(2)gas sensor Room temperature detection Core-shell structure SnSe/SnO_(2)composite Debye length