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Adjusting Sink Location to Reduce End-to-End Delay in Low-Duty-Cycle Wireless Sensor Networks

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Journal of Electronic Science and Technology 2015年第1期13卷 20-26页

作者： yu-yuan lin Kuo-Feng Ssu Hau-yu Chiang Institute of Computer and Communication Engineering National Cheng Kung University Department of Electrical Engineering National Cheng Kung University Data Systems Consulting Co. Ltd

Low-duty-cycle mechanisms can reduce the energy consumption significantly in wireless sensor networks（WSNs）. Sensors stay dormant most of the time to save their energy and wake up based on their needs. However, such a technique, while prolonging the network lifetime, sets excessive challenges for reducing the end-to-end（E2E） delay within the network. In this paper, the centralized cluster-based location finding（CCLF） algorithm is proposed to reduce the high latency in low-duty-cycle WSNs by finding a suitable position for the sink. The algorithm is mainly composed of three steps： a） the cluster construction, b） the fast look-up table（FLU-table） construction, and c） the sink location decision. The simulation results show that the performance of the CCLF algorithm is significantly similar to that of the optimal algorithm. Moreover, the CCLF algorithm requires less operation time compared with the optimal algorithm.

关键词： Duty cycle latency sink wireless sensor networks

LES NUMERICAL SIMULATION OF CAVITATION BUBBLE SHEDDING ON ALE 25 AND ALE 15 HYDROFOILS

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Journal of Hydrodynamics 2009年第6期21卷 807-813页

作者： LIU De-min LIU Shu-hong WU yu-lin XU Hong-yuan State Key Laboratory of Hydro Science and Hydraulic Engineering Department of Thermal Engineering Tsinghua University Beijing 100084 China

A cavitation calculation scheme is developed and applied to ALE 15 and ALE 25 hydrofoils, based on the Bubble Two-phase Flow （BTF） cavity model with a Large Eddy Simulation （LES） methodology. The Navier-Stokes equations including cavitation bubble clusters are solved through the finite-volume approach with a time-marching scheme. Simulations are carried out in a 3-D field with a hydrofoil ALE 15 or ALE 25 at an angle of attack of 8^0 and cavitation number σ = 2.3 with α 2× 10^6, meshing system. With the time-marching, the cavitation bubble gradually grows to a steady lump shape and then produces an irregular small bubble behind the main cavitation bubble, finally shedding from the leading edge of the cloud cavitation structure. The calculated results including velocity field and pressure field are consistent with experiment data at the same Reynolds number and cavitation number. The vortex and reverse flow are observed on the hydrofoil surface.

关键词： cavitation ALE hydrofoil Large Eddy Simulation (LES)

Extraction method of typical IEQ spatial distributions based on low-rank sparse representation and multi-step clustering

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Building Simulation 2024年第6期17卷 983-1006页

作者： yuren Yang Yang Geng Hao Tang Mufeng yuan Juan yu Borong lin School of Architecture Tsinghua UniversityBeijingChina Key Laboratory of Eco Planning&Green Building Ministry of EducationTsinghua UniversityBeijingChina

Indoor environment quality(IEQ)is one of the most concerned building performances during the operation *** non-uniform spatial distribution of various IEQ parameters in large-scale public buildings has been demonstrated to be an essential factor affecting occupant comfort and building energy ***,IEQ sensors have been widely employed in buildings to monitor thermal,visual,acoustic and air ***,there is a lack of effective methods for exploring the typical spatial distribution of indoor environmental quality parameters,which is crucial for assessing and controlling non-uniform indoor *** this study,a novel clustering method for extracting IEQ spatial distribution patterns is ***,representation vectors reflecting IEQ distributions in the concerned space are generated based on the low-rank sparse ***,a multi-step clustering method,which addressed the problems of the“curse of dimensionality”,is designed to obtain typical IEQ distribution patterns of the entire indoor *** proposed method was applied to the analysis of indoor thermal environment in Beijing Daxing international airport *** a result,four typical temperature spatial distribution patterns of the terminal were extracted from a four-month monitoring,which had been validated for their good *** typical patterns revealed typical environmental issues in the terminal,such as long-term localized overheating and temperature increases due to a sudden influx of *** extracted typical IEQ spatial distribution patterns could assist building operators in effectively assessing the uneven distribution of IEQ space under current environmental conditions,facilitating targeted environmental improvements,optimization of thermal comfort levels,and application of energy-saving measures.

关键词： indoor environment quality(IEQ) thermal environment spatial distribution temperature field low-rank sparse representation(LRSR) clustering

Lipid metabolism, amino acid metabolism, and prostate cancer: a crucial metabolic journey

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Asian Journal of Andrology 2024年第2期26卷 123-134页

作者： lin Chen yu-Xin Xu yuan-Shuo Wang Jian-Liang Zhou School of Pharmacy Hangzhou Normal UniversityHangzhou 311121China Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province Hangzhou Normal UniversityHangzhou 311121China School of Pharmacy Guangxi Medical UniversityNanning530021China

Prostate cancer(PCa)is one of the most common malignancies in males worldwide,and its development and progression involve the regulation of multiple metabolic *** in lipid metabolism affect the proliferation and metastatic capabilities of PCa *** cells increase lipid synthesis and regulate fatty acid oxidation to meet their growth and energy ***,changes occur in amino acid metabolism in *** cells exhibit an increased demand for specific amino acids,and they regulate amino acid transport and metabolic pathways to fulfill their proliferation and survival *** changes are closely associated with disease progression and treatment response in PCa ***,a comprehensive investigation of the metabolic characteristics of PCa is expected to offer novel insights and approaches for the early diagnosis and treatment of this disease.

关键词： amino acid metabolism lipid metabolism metabolic pathways prostate cancer treatment strategies

Experimental study on ice monitoring method for 10 kV transmission line with tangent tower in alpine landform

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High Voltage 2024年第1期9卷 182-194页

作者： lin Yang Zhiqiang Chen Yanpeng Hao Xinhao lin Lei yu yue Li Zhiyong yuan Licheng Li School of Electric Power South China University of TechnologyGuangzhouChina Electrical Power Research Institute China Southern Power GridGuangzhouChina Electric Power Research Institute of Guizhou Power Grid Co.Ltd. GuizhouChina

Ice monitoring methods were applied for 110 kV and above transmission lines with tangent ***,the change in the vertical span is not considered,and a significant difference lies in the tower-conductor structure of 10 kV transmission *** this reason,a proposal is made about the ice monitoring method for the 10 kV transmission line with tangent tower in alpine landform,which includes the ice monitoring system based on pressure measurement and corresponding equivalent ice thickness calculating *** methods calculate the vertical span under different height difference coefficients.A finite element simulation model and a simulated ice load experiment system are established based on real conductors and *** and simulations under four simulated terrains are conducted within 2.5–20 mm ice thickness *** comparison is made between this method and the method without considering the change in vertical *** results show that the two methods are consistent and the relative errors are lower than�4%in simulation and�10%in experiment when the height difference coefficient is *** it is not 0,the relative errors of this method fall between t0.38%and t6.78%in simulation and−6.40%to t6.60%in experiment,while the relative errors of the method without considering the change in vertical span ranges between−11.13%and−20.23%in simulation and−11.65%to−23.20%in experiment.

关键词： methods tangent method

A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures

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Petroleum Science 2024年第4期21卷 2583-2599页

作者： Jun Li Ming-Yi Wu Xu Han Si-yuan He Ze-yu lin State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Particles Energy and Technology Co. Ltd Chongqing Industry Polytechnic College Petroleum Systems Engineering Faculty of Engineering and Applied Science University of Regina

Low-permeability reservoirs are generally characterized by low porosity and low permeability. Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor. In recent years, hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing ***, the transportation of the proppant is inefficient in the low-viscosity fluid, and the proppant has a low piling-up height in fracture channels. These key challenges restrict the fluid(natural gas or oil) flow in fracture channels and their functional flow areas, reducing the profits of hydrocarbon *** study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber. Its structure was similar to that of dandelion seeds, and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional ***, the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model, rough fracture model,narrow fracture model, complex fracture model, large-scale single fracture model, and small-scale single fracture model). Experimental results indicated that, compared with the traditional proppant, the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid. Compared with the traditional proppant, the dandelionbased bionic proppant had 0.1-4 times longer transportation length, 0.3-5 times higher piling-up height, and 2-10 times larger placement area. The newly developed proppant also had some other extraordinary features. The tortuosity of the fracture did not influence the transportation of the novel proppant. This proppant could easily enter the branch fracture and n

关键词： Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation

Path-Dependent Progressive Failure Analysis for 3D-Printed Continuous Carbon Fibre Reinforced Composites

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 84-93页

作者： yuan Chen lin Ye School of System Design and Intelligent Manufacturing(SDIM) Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Intelligent Manufacturing for Continuous Carbon Fibre Reinforced Composites Southern University of Science and TechnologyShenzhen 518055China

In order to predict the damage behaviours of 3D-printed continuous carbon fibre(CCF)reinforced composites,when additional short carbon fibre(SCF)composite components are employed for continuous printing or special functionality,a novel path-dependent progressive failure(PDPF)numerical approach is ***,a progressive failure model using Hashin failure criteria with continuum damage mechanics to account for the damage initiation and evaluation of 3D-printed CCF reinforced polyamide(PA)composites is developed,based on actual fibre placement trajectories with physical measurements of 3D-printed CCF/PA ***,an elastic-plastic model is employed to predict the plastic damage behaviours of SCF/PA ***,the accuracy of the PDPF model was validated so as to study 3D-printed CCF/PA composites with either negative Poisson's ratio or high *** results demonstrate that the proposed PDPF model can achieve higher prediction accuracies in mechanical properties of these 3D-printed CCF/PA *** analyses show that the stress distribution is generally aggregated in the CCF areas along the fibre placement paths,and the shear damage and matrix tensile/compressive damage are the key damage *** study provides a new approach with valuable information for characterising complex 3D-printed continuous fibre-matrix composites with variable mechanical properties and multiple constituents.

关键词： 3D printing Continuous carbon fibre Modelling Energy absorption Negative Poisson's ratio

Enhanced potassium storage of carbon nanofibers as binderfree anodes enabled by coupling ultra-small amorphous Sb_(2)O_(3),graphene modification and sulfur doping

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Rare Metals 2024年第1期43卷 51-64页

作者： Zhao Huang yu-Kang Lou lin Peng yuan Peng Meng-Meng Wang Ming Zhang College of Railway Transportation Hunan University of TechnologyZhuzhou 412007China College of Semiconductors(College of Integrated Circuits) Changsha Semiconductor Technology and Application Innovation Research InstituteHunan UniversityChangsha 410082China Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education College of Semiconductors(College of Integrated Circuits)Hunan UniversityChangsha 410082China

Considering the intrinsic advantages of natural copiousness and cost-effectiveness of potassium resource,potassium-ion batteries(KIBs) are booming as prospective alternatives to lithium-ion batteries(LIBs) in large-scale energy storage scenarios. Nevertheless, lacking desirable electrodes for reversibly hosting the bulky K+hinders the widespread application of KIBs, and it needs to be urgently solved. Hereon, the porous S-doped Sb_(2)O_(3)-graphene-carbon(SAGC) nanofibers are manufactured through an adjustable and facile approach, which involves electrospinning, in situ etching and sulfuration. The synthesized SAGC is featured by the ultra-small amorphous Sb_(2)O_(3) homogeneously wrapped inside the carbon matrix, as well as the co-incorporation of graphene and sulfur. Tentatively,the SAGC nanofiber sheets are applied as binder-free anodes for KIBs, exhibiting a prominent cycling life(256.72 m Ah·g^(-1) over 150 cycles at 100 m A·g^(-1)) and rate·g^(-1) over 100 cycles at 1 A·g^(-1)). The positive synergy among all the active components accounts for the distinguished performances of the SAGC. By reinforcing the tolerability to the swelling stress, producing the valid electrochemical active sites, and promoting the charge transferring for reversible K+uptake, the SAGC finally renders the excellent cyclability, capacity, and rate capability. Moreover, the extrinsic electrochemical pseudocapacitance characteristics induced by the porous carbon substrate elevate the K-storage capacity of the SAGC as well. It is hoped that the conclusions drawn may offer new insights into a direction for the high-performance binderfree KIB anodes.

关键词： S-doped Sb_(2)O_(3)-graphene-carbon Nanofibers Binder-free Anodes Potassium-ion batteries

Revealing the specific role of sulfide and nano-alumina in composite solid-state electrolytes for performance-reinforced ether-nitrile copolymers

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Journal of Energy Chemistry 2024年第4期91卷 628-636页

作者： Haoyang yuan Changhao Tian Mengyuan Song Wenjun lin Tao Huang Aishui yu Department of Chemistry Collaborative Innovation Center of Chemistry for Energy MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsInstitute of New EnergyFudan UniversityShanghai 200438China Laboratory of Advanced Materials Fudan UniversityShanghai 200438China

Composite solid-state electrolytes represent a critical pathway that balances the interface compatibility and lithium-ion conductivity in all-solid-state *** quest for stable and highly ion-conductive combinations between polymers and fillers is vital,but blind attempts are often made due to a lack of understanding of the mechanisms involved in the interaction between polymers and ***,we employ in-situ polymerization to prepare a polymer based on an ether-nitrile copolymer with high cathode stability as the foundation and discuss the performance enhancement mechanisms of argyrodite and *** 1%content of sulfide interacting with the polymer at the two-phase interface,the local enhancement of lithium-ion migration capability can be achieved,avoiding the reduction in capacity due to the low ion conductivity of the passivation layer during *** capacity retention after 50cycles at 0.5 C increases from 83.5%to 94.4%.Nano-alumina,through anchoring the anions and interface inhibition functions,eventually poses an initial discharge capacity of 136.8 m A h g^(-1)at 0.5 C and extends the cycling time to 1000 h without short-circuiting in lithium metal *** the combined action of dual fillers on the composite solid-state electrolyte,promising insights are provided for future material design.

关键词： Composite solid-state electrolytes Lithium metal anode Dual fillers Interfacial ionic conduction Inert nano-alumina