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Integrated Clustering and Routing Design and Triangle Path Optimization for UAV-Assisted Wireless Sensor Networks

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China Communications 2024年第4期21卷 178-192页

作者： Shao Liwei Qian Liping wu Mengru wu Yuan College of Information Engineering Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Internet of Things for Smart City University of MacaoMacaoChina Department of Computer and Information Science University of MacaoMacaoChina

With the development of the Internet of Things(IoT),it requires better performance from wireless sensor networks(WSNs),such as larger coverage,longer lifetime,and lower ***,a large amount of data generated from monitoring and long-distance transmission places a heavy burden on sensor nodes with the limited battery *** this,we investigate an unmanned aerial vehicles assisted mobile wireless sensor network(UAV-assisted WSN)to prolong the network lifetime in this ***,we use UAVs to assist the WSN in collecting *** the current UAV-assisted WSN,the clustering and routing schemes are determined ***,such a separate consideration might not maximize the lifetime of the whole WSN due to the mutual coupling of clustering and *** efficiently prolong the lifetime of the WSN,we propose an integrated clustering and routing scheme that jointly optimizes the clustering and routing *** the whole network space,it is intractable to efficiently obtain the optimal integrated clustering and routing ***,we propose the Monte-Las search strategy based on Monte Carlo and Las Vegas ideas,which can generate the chain matrix to guide the algorithm to find the solution *** point-to-point collection leads to long collection paths,so a triangle optimization strategy is then proposed that finds a compromise path to shorten the collection path based on the geometric distribution and energy of sensor *** avoid the coverage hole caused by the death of sensor nodes,the deployment of mobile sensor nodes and the preventive mechanism design are *** emergency data transmission mechanism is further proposed to reduce the latency of collecting the latency-sensitive data due to the absence of *** with the existing schemes,the proposed scheme can prolong the lifetime of the UAVassisted WSN at least by 360%,and shorten the collection path of UAVs by 56.24%.

关键词： Monte-Las search strategy triangle path optimization unmanned aerial vehicles wireless sensor networks

Terminal-selective C（sp3）–H borylation of unbranched alkanes enabled by intermolecular radical sampling and LMCT photocatalysis

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National Science Review 2024年第5期11卷 96-98页

作者： Zhexuan Lei Jie wu Department of Chemistry National University of Singapore

The selective functionalization of C（sp3）–H bonds with subtle differences in alkanes is highly sought after due to its atom-and step-efficiency. The activation of C（sp3）–H bonds through hydrogen atom transfer （HAT） has been extensively exploited to produce a valueadded product from unfunctionalized material [1,2].

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BSIN: A Behavior Schema of Information Networks Based on Approximate Bisimulation

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Tsinghua Science and Technology 2024年第4期29卷 1092-1104页

作者： wujie Hu Jinzhao wu School of Electrical Engineering Guangxi UniversityNanning 530004China

Information networks are becoming increasingly important in practice. However, their escalating complexity is gradually impeding the efficiency of data mining. A novel network schema called the Behavior Schema of Information Networks (BSIN) is proposed to address this issue. This work defines the behavior of nodes as connected paths in BSIN, proposes a novel function distinguish behavior differences, and introduces approximate bisimulation into the acquisition of quotient sets for node types. The major highlight of BSIN is its ability to directly obtain a high-efficiency network on the basis of approximate bisimulation, rather than reducing the existing information network. It provides an effective representation of information networks, and the resulting novel network has a simple structure that more efficiently expresses semantic information than current network representations. The theoretical analysis of the connected paths between the original and the obtained networks demonstrates that errors are controllable;and semantic information is approximately retained. Case studies show that BSIN yields a simple network and is highly cost-effective.

关键词： data mining information network approximate bisimulation controllable error

Benzoyl cyanide, a general radical acylating reagent for photoredox-catalyzed benzylic site-selective acylation reactions

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Science China Chemistry 2024年第11期67卷 3833-3843页

作者： Zhaodong Zhu Jingjing wu Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced Study Shanghai Jiao Tong University

Based on rational design, benzoyl cyanide, a well-known ionic acylating reagent, has been developed as a general radical acylating reagent for benzylic site-selective acylation reactions for the first time. Using visible-light photoredox-catalyzed single electron transfer(SET) and hydrogen atom transfer(HAT) strategies, two different direct benzylic C–H acylation reactions with high atom economy have been developed. This newly developed radical acylating reagent could also be used to achieve three component acyltrifluoromethylation of styrenes, which is usually challenging to achieve by other means. All of these reactions proceed under mild nickel-free and NHC-free conditions with high functional group tolerance. In addition, based on our detailed mechanistic experiments, the process of radical-radical cross-coupling mechanism was suggested for these transformations.

关键词： photoredox catalysis benzylic C–H acylation radical acylating reagent HAT catalysis acyltrifluoromethylation

3D simulation of image-defined complex internal features using the numerical manifold method

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Science China(Technological Sciences) 2024年第4期67卷 1023-1039页

作者： wu Jie MA GuoWei School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Tianjin Key Laboratory for Prefabricated Building and Intelligent Construction Tianjin 300401China

The numerical simulation of internal features,such as inclusions and voids,is important to analyze their impact on the performance of composite ***,the complex geometries of internal features and the induced continuous-discontinuous(C-D)deformation fields are challenges to their numerical *** this study,a 3D approach using a simple mesh to simulate irregular internal geometries is developed for the first *** the help of a developed voxel crack model,image models that are efficient when recording complex geometries are directly imported into the *** reconstructions,which are usually labor-intensive,are excluded from this ***,using image models as the geometric input,image processing techniques are applied to detect material interfaces and develop contact ***,the C-D deformations of the complex internal features are directly calculated based on the numerical manifold *** accuracy and convergence of the developed3D approach are examined based on multiple *** 3D C-D simulation of sandstones with naturally formed complex microfeatures demonstrates the capability of the developed approach.

关键词： 3D continuous-discontinuous simulation image-based simulation complex internal features numerical manifold method voxel crack model structured mesh

Geometric approach to robust quantum control for time-varying noises

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 197-198页

作者： Rebing wu Center for Intelligent and Networked Systems Department of AutomationTsinghua UniversityBeijing 100084China

Quantum technologies are expected to revolutionze modern information processing *** all quntum technologies demand high-precision control of quantum ***,maintaining the high-precision against noises is rather difficult[1].This requirement calls for robust control pulse design that is insensitive to *** practical implementation,the control pulses need to be smoothly shaped and be able to tackle parametric uncertainties or time-varying noises with complicated frequency characteristics.

关键词： quantum smoothly shaped

Elucidating and manipulating pressure-induced water intrusion–extrusion in tunable hydrophobic Co/Zn bimetallic ZIFs:Roles of pore size and hydrogen bond

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Nano Research 2024年第1期17卷 344-353页

作者： Diyi Fang Chuanlei Liu Yu Chen Qilong Peng Kongguo wu Yuxiang Chen Hao Jiang Yuan wu Benxian Shen Qiumin wu Di wu Hui Sun International Joint Research Center of Green Energy Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Alexandra Navrotsky Institute for Experimental Thermodynamics The Gene and Linda Voiland School of Chemical Engineering and BioengineeringMaterials Science and Engineeringand Department of ChemistryWashington State UniversityWashington 99163USA

Porous heterogeneous lyophobic systems(HLSs)find potential applications in energy restoring,dissipating,and ***,the development of controllable HLSs still lacks rational structure design of nanoporous materials matching the molecular sizes of adopted *** that,thoroughly understanding the underlying transportation mechanism in the confined nano channels is greatly *** this work,a series of Co/Zn bimetallic zeolitic imidazolate frameworks(ZIFs)with tunable structures were synthesized via regulating the Co to Zn ratios and employed to investigate the intrusion–extrusion of liquid water in confined *** characterizations confirm the heterometallic coordination in the Co/Zn-doped *** intrusion–extrusion experiments unlock the relationship between the intrusion pressure and the nanopore size and realize the evolution of the HLSs between molecular spring and *** addition,cycling tests indicate the reversible structure change of Co/Zn ZIFs encountering pressure-induced water *** combination with molecular dynamics simulations,we present that the water multimers intrude into nanopores of ZIFs in chain-like forms along with dissociation of hydrogen bonds(HBs).Water molecules in the pre-intrusion state exhibit reduced HBs in response to the increase of pressure and linear structure with 1.6–3.0 HBs on *** transition to the post-intrusion situation,the associative configuration of water tends to exhibit the tetrahedral ***,we highlight the roles of pore size and HB in synergically dominating the pressure-induced intrusion–extrusion of liquid water in hydrophobic ***,the present work can also guide the development of functional guest–host systems based on porous architectures.

关键词： heterometallic zeolitic imidazolate frameworks nanopore intrusion hydrogen bonds

Safety-Critical Trajectory Tracking for Mobile Robots With Guaranteed Performance

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2033-2035页

作者： Wentao wu Di wu Yibo Zhang Shukang Chen Weidong Zhang Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Department of Information and Communication Engineering Hainan UniversityHaikou 570288China

Dear Editor,This letter considers a collision-free trajectory tracking problem for performance-guaranteed mobile robots(MRs)subject to *** propose a safety-critical performance-guaranteed trajectory tracking method based on control barrier functions(CBFs).First,an auxiliary system is established to generate the non-negative signals for inflexible bounds such that the performance constraints are not violated when avoiding obstacles.

关键词： constraints bounds collision

Numerical simulation of fluid-thermal-structural coupling characteristics of stratospheric non-rigid airship

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Chinese Journal of Aeronautics 2024年第9期37卷 224-236页

作者： Huafei DU Mingyun LYU Chuan YU Yifei wu Yongmei wu Kangwen SUN School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Linzhou(Ningbo)Technology Co.Ltd Yuyao 315042China

The voluminous stratospheric non-rigid airship is very sensitive to the external thermal *** temperature change of internal gas caused by the variation in the external ther-mal environment and wind speed will lead to a change in the shape and buoyancy of the airship,thereby affecting its flight *** traditional static analysis method is difficult to accurately reflect this fuid-thermal-structural coupling *** this paper,the iterative analysis method was established for the fluid-thermal-structural coupling effect of stratospheric non-rigid airship based on the models of fluid,thermal,and structural *** the load such as the internal thermal effect and external flow field of the airship,the simulation of the thermo-induced structural deformation effect was conducted using Fluent and Abaqus *** influ-ence of local time and external wind speed on the structural deformation,volume,and equilibrium altitude of the airship was *** results demonstrate that,at low wind speed,the influence of aerodynamic pressure on the deformation of the airship is ***,a great amount of heat is carried away by the wind,then the structural deformation caused by internal and external pressure difference is alleviated and the equilibrium altitude of the airship change *** can serve as a guideline for the design and flight test of the long-endurance stratospheric non-rigid airship.

关键词： Altitude change Fluid-thermal-structural coupling Stratospheric non-rigid airship Structural deformation Wind speed