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Estimation of hydraulic parameters from pumping tests in a multiaquifer system

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Underground Space 2020年第3期5卷 210-222页

作者： da ha Gang Zheng haizuo Zhou Chaofeng Zeng Huihui Zhang School of Civil Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Coast Civil Structure Safety of ministry of Education Tianjin UniversityTianjin 300072China Hunan Provincial Key Laboratory of Geotechnical Engineering for Stability Control and Health monitoring School of Civil EngineeringHunan University of Science and TechnologyXiangtanHunan 411201China School of Resources and Environmental Sciences Wuhan UniversityWuhan 430079China

The hydrogeologic conditions in Tianjin,China,are characterized by a system of multiple alternating aquifers and aquitards and a high groundwater ***,the groundwater system to a depth of 70 m includes one phreatic aquifer and three semiconfined aquifers(AqI–AqIII).The distribution of aquifers varies *** estimates of aquifer parameters from pumping tests are essential in geotechnical engineering *** this study,the applicability of different models for estimating hydraulic parameters in a multiaquifer system is *** avoid errors in the graphic-analytical process and to enhance the efficiency and accuracy,a hybrid algorithm,called GALmA(a genetic algorithm(GA)combined with the Levenberg–marquardt(Lm)algorithm),is used with the Neuman and Witherspoon model and ratio *** estimated values in the second and third semiconfined aquifers(AqII and AqIII)from various solutions are compared with the measured *** validations based on the prediction of the drawdown values are performed via a three dimensional numerical simulation.

关键词： Hydraulic parameter Leaky aquifer Pumping test Optimal approach

Development of a coupled supersonic inlet-fan Navier–Stokes simulation method

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Chinese Journal of Aeronautics 2018年第2期31卷 237-246页

作者： Qiushi LI Yongzhao LYU Tianyu PAN da LI ha'nan LU Yifang GONG National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeoing 100191 China School of Energy and Power Engineering Beihang University Beijing 100083 China Collaborative Innovation Center of Advanced Aero-Engine Beihang University Beijing 100083 China GL-Turbo Compressor Company Wuxi 214106 China

A coupled supersonic inlet-fan Navier–Stokes simulation method was developed by using COmSOL-CFD code. The flow turning, pressure rise and loss effects across blade rows of the fan and the inlet-fan interactions were taken into account as source terms of the governing equations without a blade geometry by a body force model. In this model, viscous effects in blade passages can also be calculated directly, which include the exchange of momentum between fluids and detailed viscous flow close to walls. NASA Rotor 37 compressor test rig was used to validate the ability of the body force model to estimate the real performance of blade rows. Calculated pressure ratio characteristics and the distribution of the total pressure, total temperature, and swirl angle in the span direction agreed well with experimental and numerical data. It is shown that the body force model is a promising approach for predicting the flow field of the turbomachinery. Then, coupled axisymmetric mixed compression supersonic inlet-fan simulations were conducted at mach number 2.8 operating conditions. The analysis includes coupled steady-state performance, and effects of the fan on the inlet. The results indicate that the coupled simulation method is capable of simulating behavior of the supersonic inlet-fan system.

关键词： Body force model Coupled simulation Rapid numerical method Supersonic inlet-fan Viscous flow

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKhaRI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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On the System Performance of mobile Edge Computing in an Uplink NOmA WSN With a multiantenna Access Point Over Nakagami-m Fading

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 668-685页

作者： Van-Truong Truong Van Nhan Vo dac-Binh ha Chakchai So-In the Faculty of Electrical-Electronic Engineering Duy Tan University the Institute of Research and Development Duy Tan University the Faculty of Information Technology Duy Tan University IEEE the Applied Network Technology(ANT)Laboratory Department of Computer ScienceCollege of ComputingKhon Kaen University

In this paper,we study the system performance of mobile edge computing(mEC)wireless sensor networks(WSNs)using a multiantenna access point(AP)and two sensor clusters based on uplink nonorthogonal multiple access(NOmA).Due to limited computation and energy resources,the cluster heads(CHs)offload their tasks to a multiantenna AP over Nakagami-m *** proposed a combination protocol for NOmA-mEC-WSNs in which the AP selects either selection combining(SC)or maximal ratio combining(mRC)and each cluster selects a CH to participate in the communication process by employing the sensor node(SN)*** derive the closed-form exact expressions of the successful computation probability(SCP)to evaluate the system performance with the latency and energy consumption constraints of the considered *** results are provided to gain insight into the system performance in terms of the SCP based on system parameters such as the number of AP antennas,number of SNs in each cluster,task length,working frequency,offloading ratio,and transmit power ***,to determine the optimal resource parameters,i.e.,the offloading ratio,power allocation of the two CHs,and mEC AP resources,we proposed two algorithms to achieve the best system *** approach reveals that the optimal parameters with different schemes significantly improve SCP compared to other similar *** use monte Carlo simulations to confirm the validity of our analysis.

关键词： mobile edge computing(mEC) Nakagami-m fading offloading selection combining(SC)/maximal ratio combining(mRC) successful computation probability(SCP) uplink nonortho-gonal multiple access(NOmA) wireless sensor networks(WSNs)

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

Peak shrinking and interpolating for PAPR reduction in m-IFoF-based mobile fronthaul

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Digital Communications and Networks 2022年第1期8卷 51-57页

作者： Luping Qin haibo Li da Chen Tao Jiang Research Center of 6G mobile Communications School of Cyber Science and Engineering Huazhong University of Science and Technology1037 Luoyu RoadWuhan 430074China State Key Laboratory of Optical Communication Technologies and Networks China Information Communication Technologies Group CorporationWuhan430074China

We apply a Peak Shrinking and Interpolating(PSI)scheme to improve the Peak-to-Average Power Ratio(PAPR)performance in multiple Intermediate-Frequency-over-Fiber(m-IFoF)based mobile *** key idea is to detect the high peaks of the signal and shrink them,and then the shrunk peak values are interpolated into the original signal to reduce the *** also compare the PSI technique with the previous Tone-Reservation(TR)technique and Phase Pre-Distortion(PPD)technique in terms of PAPR reduction effect and computational *** simulation results indicate that the PSI scheme can reduce the PAPR by more than 4.3 dB at 0.1%CCDF,which outperforms the two previous schemes with lower computational ***,we find that altering m-IFoF system parameters has little effect on the performance of the PSI technique.

关键词： mobile fronthaul multi-IF-Over-Fiber(m-IFoF) Peak Shrinking and Interpolating(PSI) Tone-Reservation(TR) Phase Pre-Distortion(PPD)

Syntheses and Crystal Structures of Four New Complexes [mn(4,4′-bip)_2(OH_2)_4](DBA)·4H_2O and [m(OH_2)(HDPA)_2]·3H_2O (m = mn,Co,Ni)

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Chinese Journal of Structural Chemistry 2006年第8期25卷 895-902页

作者： LIU Ying DOU Jian-min WANG da-Qi LI da-Cheng XU Feng ZHOU Lei SU Huai-Jing College of Chemistry and Chemical Engineering Liaocheng University 252059 China

Four new transition metal complexes, [mn（4,4′-bip）2（OH2）4]（DBA）-4H2O 1 （4,4′-hip = 4,4′-bipyridine, H2DBA = benzene-1,3-dicarboxylic acid） and [m（OH2）（HDPA）2]-3H2O （m = mn 2, m = Co 3, m = Ni 4, H2DPA = 2,6-pyridine-dicarboxylic acid）, have been prepared from the reaction of transition metals and carboxylic acids, and characterized by X-ray and elemental analyses. For compound 1, the packing diagram shows that a three-dimensional network is formed via hydrogen bonds and strong π-πinteractions. For compounds 2, 3 and 4, a double-helical chain is formed through hydrogen bonds. moreover, a three-dimensional network is constructed from chains via complicated hydrogen bonds between crystal water molecules and oxygen atoms of HDPA^-.

关键词： manganese cobalt nickel 4,4′-bipyridine benzene-1,3-dicarboxylic acid 2,6-pyridine-dicarboxylic acid X-ray analysis

machine learning applications on lunar meteorite minerals:From classification to mechanical properties prediction

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International Journal of mining Science and Technology 2024年第9期34卷 1283-1292页

作者： Eloy Peña-Asensio Josep m.Trigo-Rodríguez Jordi Sort Jordi ibáñez-Insa Albert Rimola Department of Aerospace Science and Technology Politecnico di MilanoMilano 20156Italy Institut de Ciències de l’Espai(ICE-CSIC) Campus UAB08193 Cerdanyola del VallèsSpain Institut d’Estudis Espacials de Catalunya(IEEC) Barcelona 08034Spain Departament de Física Universitat Autònoma de BarcelonaCerdanyola del Vallès E-08193Spain InstitucióCatalana de Recerca i Estudis Avançats(ICREA) Barcelona E-08010Spain Geosciences Barcelona(GEO3BCN-CSIC) E-08028 BarcelonaSpain Departament de Química Universitat Autònoma de BarcelonaBellaterra 08193Spain

Amid the scarcity of lunar meteorites and the imperative to preserve their scientific value,nondestructive testing methods are *** translates into the application of microscale rock mechanics experiments and scanning electron microscopy for surface composition *** study explores the application of machine Learning algorithms in predicting the mineralogical and mechanical properties of DHOFAR 1084,JAH 838,and NWA 11444 lunar meteorites based solely on their atomic percentage *** a prior-data fitted network model,we achieved near-perfect classification scores for meteorites,mineral groups,and individual *** regressor models,notably the KNeighbor model,provided an outstanding estimate of the mechanical properties—previously measured by nanoindentation tests—such as hardness,reduced Young’s modulus,and elastic *** considerations on the nature and physical properties of the minerals forming these meteorites,including porosity,crystal orientation,or shock degree,are essential for refining *** findings underscore the potential of machine Learning in enhancing mineral identification and mechanical property estimation in lunar exploration,which pave the way for new advancements and quick assessments in extraterrestrial mineral mining,processing,and research.

关键词： meteorites moon mineralogy machine learning mechanical properties

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biología molecular Severo Ochoa(CBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting