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Deployment optimization for target perpetual coverage in energy harvesting wireless sensor network

Digital Communications and Networks 2024年第2期10卷 498-508页

作者： Zhenkun jin Yixuan Geng Chenlu zhu Yunzhi Xia Xianjun Deng Lingzhi Yi Xianlan Wang Wuhan Business University 430056China Wuhan Research Institute of Post and Telecommunication Wuhan430074China Hubei Key Laboratory of Distributed System Security Hubei Engineering Research Center on Big Data SecuritySchool of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Hubei Chutian Expressway Digital Technology Co.Ltd Wuhan430074China School of Information and Safety Engineering Zhongnan University of Economics and LawWuhan430073China

Energy limitation of traditional Wireless Sensor Networks(WSNs)greatly confines the network lifetime due to generating and processing massive sensing data with a limited *** energy harvesting WSN is a novel network architecture to address the limitation of traditional ***,existing coverage and deployment schemes neglect the environmental correlation of sensor nodes and external energy with respect to physical *** considering the spatial correlation of the environment and the uneven distribution of energy in energy harvesting WSN,we investigate how to deploy a collection of sensor nodes to save the deployment cost while ensuring the target perpetual *** Confident Information Coverage(CIC)model is adopted to formulate the CIC Minimum Deployment Cost Target Perpetual Coverage(CICMTP)problem to minimize the deployed sensor *** the CICMTP is NP-hard,we devise two approximation algorithms named Local Greedy Threshold Algorithm based on CIC(LGTA-CIC)and Overall Greedy Search Algorithm based on CIC(OGSA-CIC).The LGTA-CIC has a low time complexity and the OGSA-CIC has a better approximation *** simulation results demonstrate that the OGSA-CIC is able to achieve lower deployment cost and the performance of the proposed algorithms outperforms GRNP,TPNP and EENP algorithms.

关键词： Energy harvesting WSN Deployment optimization Confident information coverage(CIC) Target perpetual coverage

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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao Jian Zheng jin guo Yunbo Shi Hengzhen Feng Jun Tang Jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

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First-Arrival Picking Method for Active Source Data with Ocean Bottom Seismometers Based on Spatial Waveform Variation Characteristics

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Journal of Ocean University of China 2024年第4期23卷 970-980页

作者： LIU Hongwei XING Lei zhu Henghua ZHANG jin ZHANG jing LIU Huaishan Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266071China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Shandong Institute of Geological Survey Jinan 250014China

The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction *** methods for first-arrival picking based on sample points are characterized by theoretical errors,especially in low-sampling-frequency OBS data because the travel time of seismic waves is not an integer multiple of the sampling *** this paper,a first-arrival picking method that utilizes the spatial waveform variation characteristics of active source OBS data is ***,the distribution law of theoretical error is examined;adjacent traces exhibit variation characteristics in their ***,a label cross-correlation superposition method for extracting highfrequency signals is presented to enhance the first-arrival picking *** from synthetic and field data verify that the proposed approach is robust,successfully overcomes the limitations of low sampling frequency,and achieves precise outcomes that are comparable with those of high-sampling-frequency data.

关键词： first-arrival picking spatial waveform variation label cross-correlation superposition method

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Molecule configurations modulate packing array and charge transfer in cocrystal engineering

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Science China Chemistry 2024年第2期67卷 512-516页

作者： Shenglong An Mengyuan Qiao Xin jin Xuanying Chen Jianhua Su Lifang guo Zhiyun Zhang Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CentreFrontiers Science Center for Materiobiology and Dynamic ChemistryEast China University of Science&TechnologyShanghai200237China

Organic cocrystal as an emerging assembly strategy has received increasing attention in constructing multiple functional materials,through continually screening suitable constituent monomers or changing their stoichiometry ***,the role of molecule configuration in the cocrystal field is rarely explored despite the fascinating potential in regulating the packing *** this study,the N,N′-diphenyl-5,10-dihydrophenazine derivatives(DPPs) with the flexible scaffold and different methyl substitutions are selected as the donors bearing various molecular *** a simple collaborative way,a series of cocrystals based on DPPs and OFN(octafluoronaphthalene) are fabricated,exhibiting two self-adaptive molecular stacking arrays.X-ray crystallographic analysis and theoretical calculation unveil their different π···π interactions and charge transfer characters,leading to the significant emission redshift up to 125 nm compared with individual *** a result,controllable molecule stacking structure,tunable emission,and charge transfer properties can be *** study provides a new perspective to reveal the structure-property relationships at the molecular level by controlling the molecule configuration in cocrystal engineering,contributing to the development of cocrystal theoretical physics and organic functional materials.

关键词： cocrystals molecular configuration self-adaptive packing mode charge transfer

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Constructing Ce-Mn/Al2O3 with different active components for low temperature catalytic degradation of chlorobenzene in soil

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Journal of Rare Earths 2024年第10期42卷 1873-1881页

作者： Tianyu Sun Mutao Xu Xuelu Meng Tiantian Liu Qijie jin Chengzhang zhu Haitao Xu School of Environmental Science and Engineering Nanjing Tech University College of Materials Science and Engineering Nanjing Tech University

Soil remediation containing numerous organic contaminants is of great significance to ecological ***,the synergetic effects of Ce-Mn/Al2O3with different active components on catalytic thermal desorption of chlorobenzene in soil were *** optimized Ce-Mn/Al2O3drastically enhance the desorption efficiency of chlorobenzene,and the corresponding conversion reaches 100%within 1 h at a low temperature of 120℃.The superior performance is ascribed to the formation of Ce-Mn solid solution during the calcination process,resulting in a certain lattice change to the generation of abundant oxygen vacancies and acidic *** with the analysis of in-situ diffuse reflectance infrared spectroscopy and gas chromatography-mass spectrometry,the final products of chlorobenzene are decomposed into CO2,H2O,Cl2and *** work sheds light on the rational design of highly-active catalysts for practical applications of sustainable soil remediation.

关键词： Ce-Mn/Al2O3 Degradation pathway Low temperature Rare earths Soil Thermal desorption

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Multimode Design and Analysis of an Integrated Leg-Arm Quadruped Robot with Deployable Characteristics

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 41-61页

作者： Fuqun Zhao Yifan Wu Xinhua Yang Xilun Ding Kun Xu Sheng guo Xiaodong jin School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

To improve locomotion and operation integration, this paper presents an integrated leg-arm quadruped robot(ILQR) that has a reconfigurable joint. First, the reconfigurable joint is designed and assembled at the end of the legarm chain. When the robot performs a task, reconfigurable configuration and mode switching can be achieved using this joint. In contrast from traditional quadruped robots, this robot can stack in a designated area to optimize the occupied volume in a nonworking state. Kinematics modeling and dynamics modeling are established to evaluate the mechanical properties for multiple modes. All working modes of the robot are classified, which can be defined as deployable mode, locomotion mode and operation mode. Based on the stability margin and mechanical modeling, switching analysis and evaluation between each mode is carried out. Finally, the prototype experimental results verify the function realization and switching stability of multimode and provide a design method to integrate and perform multimode for quadruped robots with deployable characteristics.

关键词： Quadruped robot Multimode design Mode switching Locomotion Operation

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Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye Da-Ming Wei Yi-Ming zhu Zhi-Ping jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

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A"messenger zone hypothesis"based on the visual three-dimensional spatial distribution of motoneurons innervating deep limb muscles

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Neural Regeneration Research 2024年第7期19卷 1559-1567页

作者： Chen Huang Shen Wang jin Deng Xinyi Gu Shuhang guo Xiaofeng Yin MoE Key Laboratory for Trauma Treatment and Nerve Regeneration Peking UniversityBeijingChina Department of Orthopedics and Trauma Peking University People’s HospitalBeijingChina

Coordinated contraction of skeletal muscles relies on selective connections between the muscles and multiple classes of the spinal motoneuro *** r,current research on the spatial location of the spinal motoneurons innervating differe nt muscles is *** this study,we investigated the spatial distribution and relative position of different motoneurons that control the deep muscles of the mouse hindlimbs,which were innervated by the obturator nerve,femoral nerve,inferior gluteal nerve,deep pe roneal nerve,and tibial *** were visualized by combining a multiplex retrograde tracking technique compatible with three-dimensional imaging of solvent-cleared o rgans(3DISCO)and 3-D imaging technology based on lightsheet fluorescence microscopy(LSFM).Additionally,we propose the hypothesis that"messenger zones"exist as interlaced areas between the motoneuron pools that dominate the synergistic or antagonist muscle *** hypothesize that these interlaced neurons may participate in muscle coordination as messenger *** revealed the precise mutual positional relationships among the many motoneurons that innervate different deep muscles of the *** only do these findings update and supplement our knowledge regarding the overall spatial layout of spinal motoneurons that control mouse limb muscles,but they also provide insights into the mechanisms through which muscle activity is coordinated and the architecture of motor circuits.

关键词： 3-D imaging motoneurons multiple retrograde tracing muscle coordination skeletal muscle spatial distribution optical tissue clearing

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Isotope constraints on seasonal dynamics of nitrogen in Zhanjiang Bay, a typical mariculture bay in South China

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Acta Oceanologica Sinica 2024年第6期43卷 60-70页

作者： Chunqing Chen Qibin Lao Fajin Chen Guangzhe jin Jiacheng Li Qingmei zhu College of Ocean and Meteorology Guangdong Ocean UniversityZhanjiang 524088China School of Chemistry and Environment Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory for Coastal Ocean Variation and Disaster Prediction Guangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environment in Continental Shelf Sea and Deep Sea of Department of Education of Guangdong ProvinceGuangdong Ocean UniversityZhanjiang 524088China

Eutrophication in coastal waters has been increasing remarkably,severely impacting the water quality in mariculture *** this study,we conducted multiple isotopic measurements on suspended particulate nitrogen(δ^(15)N-PN) and dissolved nitrate(δ^(15)N-NO_(3)^(-)and δ^(18)O-NO_(3)^(-)) in Zhanjiang Bay,a typical mariculture bay with a high level of eutrophication in South China,to investigate the changes in nitrogen sources and their cycling between the rainy and dry *** the rainy season,the study found no significant relation between δ^(15)NPN and δ^(15)N-NO_(3)^(-)due to the impact of heavy rainfall and terrestrial *** the upper bay,a slight nitrate loss and slightly higher δ_(15)N-NO_(3)^(-)and δ^(18)O-NO_(3)^(-)values were observed,attributed to intense physical sedimentwater *** some fluctuations,nitrate concentrations in the lower bay mainly aligned with the theoretical mixing line during the rainy season,suggesting that nitrate was primarily influenced by terrestrial erosion and that nitrate isotopes resembled the ***,the isotopic values of nitrate can be used for source apportionment in the rainy *** results indicated that soil nitrogen(36%) and manure and sewage(33%) were the predominant nitrogen sources contributing to nitrogen loads during this *** contrast,the dry season saw a deficient ammonium concentration(<0.2 μmol/L) in the bay,due to nearly complete consumption by phytoplankton during the red tide ***,the significant loss of nitrate and simultaneous increase in the stable isotopes of dissolved and particulate nitrogen suggest a strong coupling of assimilation and mineralization during the dry *** active biogeochemical processes during the dry season may be related to decreased runoff and increased water retention ***,our study illustrated the major seasonal nitrogen sources and their dynamics in Zhanjiang B ay,providing valuable insights for formulati

关键词： nitrogen stable nitrogen isotopes biogeochemical processes eutrophication Zhanjiang Bay

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Tailoring Ni based catalysts by indium for the dehydrogenative coupling of ethanol into ethyl acetate

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Green Energy & Environment 2024年第8期9卷 1321-1331页

作者： Ming Yin Jifeng Pang jin guo Xianquan Li Yujia Zhao Pengfei Wu Mingyuan Zheng CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Materials Science and Engineering Dalian Jiaotong University

Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising ***,novel NiIn based catalysts were developed by tailoring Ni catalysts with Indium （In） for this *** the optimal Ni0.1Zn0.7Al0.3InOx catalyst,the ethyl acetate selectivity reached 90.1%at 46.2%ethanol conversion under the conditions of 548 K and a weight hourly space velocity of 1.9 h-1in the 370 h time on ***,the ethyl acetate productivity surpassed1.1 gethyl acetateg-1catalysth-1,one of the best performance in current *** to catalyst characterizations and conditional experiments,the active sites for dehydrogenative coupling of ethanol to ethyl acetate were proved to be Ni4In *** presence of In tailored the chemical properties of Ni,and subsequently inhibited the C±C cracking and/or condensation reactions during ethanol *** Ni4In alloy sites,ethanol was dehydrogenated into acetaldehyde,and then transformed into acetyl species with the removal of H ***,the coupling between acetyl species and surface-abundant ethoxyde species into ethyl acetate was achieved,affording a high ethyl acetate selectivity and catalyst stability.

关键词： Dehydrogenative coupling Ethanol Ethyl acetate Nickel and indium alloys

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