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From Elastic Spin to Phonon Spin:Symmetry and Fundamental Relations

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Chinese Physics Letters 2022年第12期39卷 41-49页

作者： Jie ren Center for Phononics and Thermal Energy Science China-EU Joint Lab on NanophononicsShanghai Key Laboratory of Special Artificial Microstructure Materials and TechnologySchool of Physics Science and EngineeringTongji UniversityShanghai 200092China

This work is mainly based on postgraduate lectures at Tongji University since 2020 *** firstly revisit the elastic spin and orbital angular momentum[*** 115,9951(2018)]but more general for anisotropic systems by applying Noether’s theorem to the elastic Lagrangian and by applying the symmetry argument in the field ***,fundamental relations between elastic energy flux and elastic spin are *** particular cases,the wave spin is closely related to the vorticity of energy flux and ***,we move forward from the elastic spin to revisit the phonon spin[Fizika Tverdogo Tela 3,2160(1961)]by applying the second quantization to elastic *** show that the uncovered phonon spin,a polarized elastic-vibration quanta,is generally not restricted to transverse phonon modes,but applying to general phonon modes,such as the longitudinal phonon modes,surface phonon modes,and hybridized phonon modes,regarded as a consequence of mode *** elastic spin and phonon spin originate from the local rotating of the field polarization in time domain,not the local circulation(vorticity)of displacement or velocity in space *** is hopeful that the present results could advance the fundamental understanding of phonon spin and elastic spin,and promote the spin phononics for hybrid quantum sensing and technology with multiple degrees of freedom.

关键词： theory phonon applying

Discrete Differential Calculus on Simplicial Complexes and Constrained Homology

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Chinese Annals of Mathematics,Series B 2023年第4期44卷 615-640页

作者： Shiquan ren School of Mathematics and Statistics Henan University

Let V be a finite *** K be a simplicial complex with its vertices in *** this paper,the author discusses some differential calculus on *** constructs some constrained homology groups of K by using the differential calculus on ***,he defines an independence hyper graph to be the complement of a simplicial complex in the complete hypergraph on *** L be an independence hypergraph with its vertices in *** constructs some constrained cohomology groups of L by using the differential calculus on V.

关键词： Simplicial complexes Hypergraphs Chain complexes Homology Differential calculus

New advances in biomimetic surface

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Science China(Technological Sciences) 2016年第10期59卷 1619-1620页

作者： ren LuQuan Key Laboratory of Bionic Engineering Ministry of Education Jilin University

Anti-adhesion is a common phenomenon in living organisms, which is the evolution results to adapt their living surroundings. From the perspective of surface type, there are two typical anti-adhesion mechanisms： micro- and nano- surface structures and liquid-covered surface. Many living organisms possess one or two of these anti-adhesion surfac- es in order to achieve superior anti-adhesion, for example, soil animals like mole cricket and earthworm [1]. Carnivo- rous pitcher plant Nepenthes can capture and digest insects to meet the fundamental nutrients needs. When the insects crawl on its slippery peristome, they could easy-sliding into the picher, known as ＂aquaplaning＂. Wong et al. [2] at Harvard University has designed and fabricated slippery surface mimicking this slippery mechanism in Nepenthes, the results of which was published in Nature. However, questions remain about the mechanism underlying its func- tion, especially for the liquid film formation mechanism.

关键词： Biomimetics Hydrophilicity

Path Computing Scheme with Low-Latency and Low-Power in Hybrid Cloud-Fog Network for IIoT

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China Communications 2023年第8期20卷 1-16页

作者： Jijun ren Peng Zhu Zhiyuan ren School of Communications and Information Engineering Xi’an University of Posts&TelecommunicationsShaanxi 710061China State Key Laboratory of Integrated Services Networks Xidian UniversityShaanxi 710071China

With the rapid development of the Industrial Internet of Things(IIoT),the traditional centralized cloud processing model has encountered the challenges of high communication latency and high energy consumption in handling industrial big data *** paper aims to propose a low-latency and lowenergy path computing scheme for the above *** scheme is based on the cloud-fog network *** computing resources of fog network devices in the fog computing layer are used to complete task processing step by step during the data interaction from industrial field devices to the cloud center.A collaborative scheduling strategy based on the particle diversity discrete binary particle swarm optimization(PDBPSO)algorithm is proposed to deploy manufacturing tasks to the fog computing layer *** task in the form of a directed acyclic graph(DAG)is mapped to a factory fog network in the form of an undirected graph(UG)to find the appropriate computing path for the task,significantly reducing the task processing latency under energy consumption *** experiments show that this scheme’s latency performance outperforms the strategy that tasks are wholly offloaded to the cloud and the strategy that tasks are entirely offloaded to the edge equipment.

关键词： collaborative offloading strategy cloudfog network architecture industrial internet of things path computing PDBPSO

A Review of Biological Fluid Power Systems and Their Potential Bionic Applications

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Journal of Bionic Engineering 2019年第3期16卷 367-399页

作者： Chunbao Liu Yingjie Wang Luquan ren Lei ren School of Mechanical and Aerospace Engineering Jilin University Changchun 130022 China Key Laboratory of Bionic Engineering Ministry of Education Jilin University Changchun 130022 China School of Mechanical Aerospace and Civil Engineering University of Manchester Manchester M13 9PL UK

Nature has always inspired human achievements in industry, and biomimetics is increasingly being applied in fluid power technology. Arachnida use hydraulic forces, rather than muscle, for leg extensions during locomotion. Many cold-blooded and soft-bodied organisms rely on a hydrostatic skeleton to transmit force, which involves a hydraulic mechanism. Biological hydraulic transmission differs from engineering hydraulic transmission in many aspects, such as in energy transfer and transformation, the movement mode, environmental friendliness, system pressure level, and energy supplement mode. The existence of a hydraulic mechanism in a biological drive requires 3 features: a power source, cavity, and working medium. The power source is similar to a hydraulic pump, and the cavity is similar to a hydraulic cylinder, both of which are necessary for producing deformation. The working medium is similar to a hydraulic fluid. Under these 3 conditions, a biological flow is generated inside or outside the body to meet the requirements of a biological drive. This paper reviews the biological organisms that employ hydraulic systems, identifies related studies on these biological hydraulic systems, and summarizes the mechanisms involved in using hydraulic pressure to achieve graceful and agile movements. This in-depth study and exploration of biological hydraulic systems can provide a good reference for solving the challenges of using hydraulic systems, such as increasing the energy efficiency, improving reliability, building smart components and systems, reducing the size and weight of components, reducing the environmental impact of systems, and improving and applying energy storage and redeployment capabilities. This paper also includes a detailed discussion of new ideas and innovative sources for the future development of hydraulic systems. In contrast with the bio-inspired designs used in other engineering fields, very few studies have reported on using bio-inspired methods

关键词： bionic fluid power pressurized liquids locomotion bio-inspired applications

A FAS approach for stabilization of generalized chained forms: part 2. Continuous control laws

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Science China(Information Sciences) 2024年第3期67卷 114-135页

作者： Guang-ren DUAN Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and Technology Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, continuous time-varying stabilizing controllers for the type of general nonholonomic systems proposed and treated in part 1 are designed using the fully actuated system(FAS) approach. The key step is to differentiate the first scalar equation, and by control of the obtained second-order scalar system, a proportional plus integral feedback form for the first control variable is obtained. With the solution to this designed second-order scalar system, the rest equations in the nonholonomic system form an independent time-varying subsystem which is then handled by the FAS approach. The overall designed controller contains an almost arbitrarily chosen design parameter, and is proven to guarantee the uniformly and globally exponential stability of the closed-loop system. The proposed approach is simple and effective,and is demonstrated with a practical example of ship control.

关键词： nonholonomic systems feedback stabilization fully actuated systems Lyapunov stability continuous controllers

强震区装配式和现浇地铁车站结构地震响应对比研究

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A FAS approach for stabilization of generalized chained forms: part 1. Discontinuous control laws

工程力学 2025年第1期42卷 164-173页

作者：江志伟杨秀仁李霞城市轨道交通绿色与安全建造技术国家工程研究中心北京100037 北京城建设计发展集团股份有限公司北京100037

以往的地下结构抗震研究大多是针对现浇结构开展的，而装配式结构由独立的预制构件拼装而成，从根本上区别于传统整体现浇结构，已有研究得到的认识对其适用性尚不明确，这极大地限制了装配式地下结构在强震区的推广与应用。该文以实际... 详细信息

以往的地下结构抗震研究大多是针对现浇结构开展的，而装配式结构由独立的预制构件拼装而成，从根本上区别于传统整体现浇结构，已有研究得到的认识对其适用性尚不明确，这极大地限制了装配式地下结构在强震区的推广与应用。该文以实际工程为背景，开展了全装配式和同型现浇车站结构的三维非线性有限元时程分析，对比了结构在八度区设防、罕遇和极罕遇地震下的变形、内力和损伤等响应。结果表明：装配式和现浇车站结构整体的地震变形差异不大，但柔性装配式车站结构榫槽节点可产生张开变形。设防和罕遇地震下，节点张开有利于结构减震，装配式车站结构的损伤小于现浇结构;而在极罕遇地震下，节点张开变大，榫槽、榫头和构件边缘的部分区域损伤集中，装配式和现浇结构地震响应产生了较大差异，但因应变幅值有限且损伤范围较小，此时全装配式与现浇车站结构整体的损伤程度基本相当。

关键词：装配式地铁车站结构地下结构抗震预制装配式地下结构装配式车站结构抗震结构地震损伤

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Science China(Information Sciences) 2024年第2期67卷 118-143页

作者： Guang-ren DUAN Center for Control Science and Technology Southern University of Science and Technology Center for Control Theory and Guidance Technology Harbin Institute of Technology

In this paper, a type of general nonholonomic systems is proposed, which contains both the Brockett's two example systems, and their extended n-dimensional chained forms, as special cases. For the stabilization of such systems, a stabilizing controller is proposed based on the fully actuated system(FAS)approach, which is discontinuous at the origin but time-invariant when the open-loop system is time-invariant,and drives the feasible trajectories of the system to the origin exponentially. Furthermore, the proposed FAS approach is also extended to the sub-normal system case and the time-delay system case.

关键词： nonholonomic systems feedback stabilization exponential convergence sub-fully actuated systems time-delay systems

H型试剂对于大直径泥水盾构泥水分离处理的影响与应用

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岩土工程学报 2025年第1期47卷 153-163页

作者：张箭任国平尹义豪钟小春张春雷梁禹河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098 中铁十四局集团大盾构工程有限公司江苏南京211800 河海大学环境学院江苏南京210098 中山大学土木工程学院广东珠海519082

针对广东湛江湾海底隧道施工中出现的盾构废弃泥浆脱水速率慢、泥渣含水率高与废浆排放污染等问题,研发了一种新型H型脱水试剂。通过絮凝脱水试验、微观机理试验以及现场生产试验,揭示了泥浆泥水分离体积比/上清液浊度/粒径分布和Zeta... 详细信息

针对广东湛江湾海底隧道施工中出现的盾构废弃泥浆脱水速率慢、泥渣含水率高与废浆排放污染等问题,研发了一种新型H型脱水试剂。通过絮凝脱水试验、微观机理试验以及现场生产试验,揭示了泥浆泥水分离体积比/上清液浊度/粒径分布和Zeta电位等变化规律,综合评价H型试剂与3种聚丙烯酰胺(PAM)在泥浆脱水效果方面的差异。结果表明:H型试剂与泥浆作用的最优添加量为0.5%;与PAM相比,H型试剂前期沉降速度较慢,但脱水后的泥渣含水率降低了约18.1%,且上清液非常清澈,7.8的pH值符合直接外排条件;H型试剂兼具了较好的桥网作用与电中和作用,使粒径<10μm的细粒更容易聚集成50μm以上的大颗粒,加快了泥浆的絮凝速度。H型试剂营造了渗水性更强的Ca排水通道,降低泥浆的黏滞性,提高泥浆压滤脱水的效率;与原脱水试剂相比,现场使用0.1%的H型试剂,可提高30.5%的脱水泥样含固率,降低20%的工程成本。

关键词：泥水盾构泥水分离絮凝脱水机理研究现场试验