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Parkland trees on smallholder farms ameliorate soil physical-chemical properties in the semi-arid area of Tigray,Ethiopia

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Journal of Arid Land 2024年第1期16卷 1-13页

作者： Selam LJALEM Emiru BIRhANE Kassa TEKA Daniel h BERhE Department of Land Resources Management and Environmental Protection College of Dryland Agriculture and Natural ResourcesMekelle UniversityMekelle 231Ethiopia Institute of Climate and Society Mekelle UniversityMekelle 231Ethiopia Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences(NMBU)Ås 1432Norway Department of Natural Resources Management Adigrat UniversityAdigrat 50Ethiopia

Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic *** African birch(Anogeissus leiocarpa(DC.)Guill.&Perr.)and pink jacaranda(Stereospermum kunthianum Cham.)trees are the dominant species in the agroforestry parkland system in the drylands of Tigray,*** farmers highly value these trees for their multifunctional uses including timber,firewood,charcoal,medicine,*** trees also could improve soil ***,the amount of soil physical and chemical properties enhanced by the two species must be determined to maintain the sustainable conservation of the species in the parklands and to scale up to similar agroecological ***,we selected twelve isolated trees,six from each species that had similar dendrometric characteristics and were growing in similar environmental *** divided the canopy cover of each tree into three radial distances:mid-canopy,canopy edge,and canopy gap(control).At each distance,we took soil samples from three different *** collected 216 soil samples(half disturbed and the other half undisturbed)from each canopy position and soil *** density(BD),soil moisture content(SMC),soil organic carbon(SOC),total nitrogen(TN),available phosphorus(AP),available potassium(AK),p h,electrical conductivity(EC),and cation exchange capacity(CEC)were *** revealed that soil physical and chemical properties significantly improved except for soil texture and EC under both species,CEC under ***,and soil p h under ***,all the studied soils were improved under both species canopy as compared with canopy ***,TN,AP,and AK under canopy of these trees were respectively 24.1%,11.1%,55.0%,and 9.3% higher than those soils under *** two parkland agroforestry species significantly enhanced soil fertility near the canopy of top

关键词： agroforestry bulk density carbon stock dispersed tree soil texture tree canopy

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Integralinput-to-statestability ystemswithsmalldelays Integral input-to-state stability of systems with small delays

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Control Theory and Technology 2024年第3期22卷 455-467页

作者： R.h.harsha Nawarathna Yuandan Lin Yuan Wang Department of Mathematical Sciences Florida Atlantic UniversityBoca RatonFL 33431USA

We consider how small delays affect the integral-input-to-state stability(iss)property for a *** result is similar to the input-to-state stability(Iss)result obtained in[1]:the iss property will be preserved in a practical and semi-global manner if the delay interval is small ***,since the iss quantifies the robust stability in terms of a generalized Li norm of the inputs instead of a generalized Loo norm of the inputs for the Iss case,the techniques and proofs for the Iss case do not apply to the iss case *** the proofs in[1]are based on the Lyapunov-Razumikhin approach,our proofs are based on the iss-Lyapunov functions for the zero-delay *** addition to the interest by its own in showing how the iss property is affected by small delays,the result also serves to the study of the iss property for singularly perturbed systems.

关键词： Integral-input-to-state stability Nonlinear systems Small delays Lyapunov method

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Dissociation cross sections ofψ(3770),ψ(4040),ψ(4160),andψ(4415)mesons with nucleons

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Communications in Theoretical Physics 2024年第4期76卷 93-112页

作者： Ruo-Qing Ding Xiao-Ming Xu h J Weber Department of Physics Shanghai UniversityBaoshanShanghai 200444China Department of Physics University of VirginiaCharlottesvilleVA 22904United States of America

We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a ■ meson leads to the dissociation of the ■ meson. We consider the reactions:■, and■, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and the ■ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the S-matrix *** cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-charmonium scattering quark interchange relativistic constituent quark potential model

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Tilted global solar irradiance in Bahrain:an experimental study

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Clean Energy 2024年第2期8卷 27-34页

作者： N.Vasilikos C.Georgantopoulou h.Alajaimi S.h.Almajed M.Ahmed D.Mathioulakis School of Mechanical Engineering Bahrain PolytechnicIsa TownPO Box 33349Kingdom of Bahrain School of Mechanical Engineering National Technical University of AthensHeroon Polytechniou 7 StZografos 15773AthensGreece

In the present work,tilted global solar irradiance data are presented and analysed,measured for a period of 1 year on the campus of Bahrain Polytechnic,Kingdom of Bahrain,from both a fixed photovoltaic panel and a moving one via a two-axis solar *** fixed panel faces south with an angle of 26°with respect to the horizontal,coinciding with the local geographical *** second panel is moved by two motors,controlled by a global positioning system and suitable software so that the Sun’s rays are perpendicular to the panel surface.A pyranometer is installed on each panel,recording the tilted global solar irradiance,stored by using a data *** analysis of the data obtained shows a 33%solar energy gain on an annual basis for the moving panel(2780 versus 2088 kWh/m^(2) on the fixed panel).More importantly,in June,when the energy demand in Bahrain is elevated due to the increased residential cooling loads,the solar energy received by the moving panel is 54.7%higher compared with that of the fixed *** a percentage basis,the increase in solar energy from the moving panel is profound in the early morning and late evening ***,the reduction in the solar energy received by the fixed panel from May to June does not appear in the moving panel because of the adjustable orientation of the *** the year,the mean daily solar power varies between 0.37 and 0.56 kW/m^(2) for the fixed panel,and 0.45 and 0.70 kW/m^(2) for the moving *** winter,solar energy fluctuations are elevated due to erratic weather conditions that present a peak standard deviation of 28%of the corresponding *** data presented are useful for potential solar investments in Gulf countries.

关键词： tilted solar irradiance renewable energy solar tracking photovoltaic Gulf Cooperation Council Countries

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Next generation multiple access for IMT towards 2030 and beyond

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Science China(Information Sciences) 2024年第6期67卷 448-450页

作者： Zhiguo DING Robert SChOBER Pingzhi FAN h.Vincent POOR Department of Computer and Information Engineering Khalifa University Department of Electrical and Electronic Engineering University of Manchester Institute for Digital Communications Friedrich Alexander-University Erlangen-Nurnberg (FAU) CSNMT International Cooperation Research Center (MoST) Southwest Jiaotong University Department of Electrical and Computer Engineering Princeton University

Multiple access techniques are fundamental to the design of wireless communication systems,since many crucial components of such systems depend on the choice of the multiple access technique[1].For example,the use of ...

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Investigation of the crystal structure and magnetic properties of Nd_(3-x)GdxCo_(11)B_4 borides

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Journal of Rare Earths 2011年第5期29卷 466-470页

作者： Seluk Kervan Nazmiye Kervan Ayse zdemir hseyin Szeri Nevsehir University Faculty of Arts and SciencesPhysics Department TUBTAK-UME National Metrology Institute

Polycrystalline samples of pseudo-ternary intermetallic Nd3–xGdxCo11B4 （x=0,1,2,3） borides prepared by standard arc-melting were characterized by X-ray powder diffraction （XRPD）,magnetization and differential scanning calorimetry （DSC） measurements. The X-ray diffraction patterns indicated the hexagonal Ce3Co11B4-type structure with P6/mmm space group for each composition. The substitution of Gd for Nd led to a decrease of the unit-cell parameters a and the unit-cell volume V,while the unit-cell parameter c increased linearly. Magnetic measurements indicated that all samples were ordered magnetically below the Curie temperature. The Curie temperatures increased as Nd was substituted by Gd. The saturation magnetization at 4 K decreased upon the Gd substitution up to x=1,and then increased.

关键词： intermetallics magnetically ordered materials magnetic measurements rare earths

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An introductory review of swarm technology for spacecraft on-orbit servicing

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International Journal of Mechanical System Dynamics 2024年第1期4卷 3-21页

作者： El Ghali Asri Zheng h.Zhu Department of Mechanical Engineering York UniversityTorontoOntarioCanada

This review paper presents a comprehensive evaluation and forward-looking perspective on the underexplored topic of servicing target objects using spacecraft *** targets can be known or unknown,cooperative or uncooperative,and pose significant challenges in modern space operations due to their inherent complexity and *** servicing space objects is vital for active debris removal and broader on-orbit servicing tasks such as satellite maintenance,repair,refueling,orbital assembly,and *** effort has been invested in the literature to explore the servicing of targets using a single *** its advantages and benefits,this paper expands the discussion to encompass a swarm approach to the *** review covers various single-spacecraft approaches and presents a critical examination of the existing,although limited,body of work dedicated to servicing orbital objects using multiple *** focus is also broadened to include some influential studies concerning the characterization,capture,and manipulation of physical objects by general multiagent systems,a subject with significant parallels to the core interest of this ***,this article also delves into the realm of simultaneous localization and mapping,highlighting its application within close-proximity operations in space,especially when dealing with unknown uncooperative *** attention is paid to the benefits that this field can receive from distributed multiagent ***,an exploration of the promising field of swarm robotics is presented,with an emphasis on its potential to revolutionize the servicing of orbital target ***,a survey of general research directly engaging swarms in the orbital context is *** review aims to bridge the knowledge gap and stimulate further research in the underexplored domain of servicing space targets with spacecraft swarms.

关键词： space robotics on-orbit servicing close-proximity operations guidance and navigation swarm robotics multiagent systems object capture and manipulation simultaneous localization and mapping

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The immune response to SARS-CoV-2 in people with hIV

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Cellular & Molecular Immunology 2024年第2期21卷 184-196页

作者： Maxine A.höft Wendy A.Burgers Catherine Riou Institute of Infectious Disease and Molecular Medicine University of Cape TownCape TownSouth Africa Division of Medical Virology Department of PathologyUniversity of Cape TownCape TownSouth Africa Wellcome Centre for Infectious Diseases Research in Africa University of Cape TownCape TownSouth Africa

This review examines the intersection of the hIV and SARS-CoV-2 *** with hIV(PWh)are a heterogeneous group that differ in their degree of immune suppression,immune reconstitution,and viral *** COVID-19 in those with wellcontrolled hIV infection poses no greater risk than that for hIV-uninfected individuals,people with advanced hIV disease are more vulnerable to poor COVID-19 ***-19 vaccines are effective and well tolerated in the majority of PWh,though reduced vaccine efficacy,breakthrough infections and faster waning of vaccine effectiveness have been demonstrated in *** is likely a result of suboptimal humoral and cellular immune responses after *** with advanced hIV may also experience prolonged infection that may give rise to new epidemiologically significant variants,but initiation or resumption of antiretroviral therapy(ART)can effectively clear persistent ***-19 vaccine guidelines reflect these increased risks and recommend prioritization for vaccination and additional booster doses for PWh who are moderately to severely *** recommend continued research and monitoring of PWh with SARS-CoV-2 infection,especially in areas with a high hIV burden.

关键词： SARS-CoV-2 hIV Immune dysfunction Vaccine efficacy Prolonged infection Immunogenicity

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Optimization of CNC cutting parameters using design of experiment(DOE) and desirability function

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Journal of Forestry Research 2018年第5期29卷 1423-1434页

作者： Ender hazir Emine Seda Erdinler Kücük hüseyin Koc Department of Forest Industrial Engineering Faculty of ForestryIstanbul University

In this study,2~5 （five factors at two-level factorial design） design of experiment was applied to investigate a set of optimal machining parameters to achieve a minimum surface roughness value for Abies *** specimens were prepared using different values of spindle speed,feed rate,depth of cut,tool radius,and cutting *** surface roughness （R_z） values were applied using a *** objectives were to：（1）obtain the effective variables of wood surface roughness;（2） analyze which of these factors had an impact on variability in the CNC machining process;（3） evaluate the optimal cutting values within the range of different cutting levels of machining *** results indicate that the design of experiment（DOE） based on the desirability function approach determined the optimal machining parameters successfully,leading to minimum R_a compared to the observed *** surface roughness values of tangential and radial cutting directions were 3.58 and 3.21 μm,respectively.

关键词： Wood surface roughness Optimization CNC Desirability function Pareto analysis

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Advanced Optimized Anomaly Detection System for IoT Cyberattacks Using Artificial Intelligence

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Computers, Materials & Continua 2024年第2期78卷 1525-1545页

作者： Ali hamid Farea Omar h.Alhazmi Kerem Kucuk Department of Computer Science Taibah UniversityMedina42315Saudi Arabia Department of Software Engineering Kocaeli UniversityKocaeli41001Turkey

While emerging technologies such as the Internet of Things(IoT)have many benefits,they also pose considerable security challenges that require innovative solutions,including those based on artificial intelligence(AI),given that these techniques are increasingly being used by malicious actors to compromise IoT *** an ample body of research focusing on conventional AI methods exists,there is a paucity of studies related to advanced statistical and optimization approaches aimed at enhancing security *** contribute to this nascent research stream,a novel AI-driven security system denoted as“AI2AI”is presented in this ***2AI employs AI techniques to enhance the performance and optimize security mechanisms within the IoT *** also introduce the Genetic Algorithm Anomaly Detection and Prevention Deep Neural Networks(GAADPSDNN)sys-tem that can be implemented to effectively identify,detect,and prevent cyberattacks targeting IoT ***,this system demonstrates adaptability to both federated and centralized learning environments,accommodating a wide array of IoT *** evaluation of the GAADPSDNN system using the recently complied WUSTL-IIoT and Edge-IIoT datasets underscores its *** an impressive overall accuracy of 98.18%on the Edge-IIoT dataset,the GAADPSDNN outperforms the standard deep neural network(DNN)classifier with 94.11%***,with the proposed enhancements,the accuracy of the unoptimized random forest classifier(80.89%)is improved to 93.51%,while the overall accuracy(98.18%)surpasses the results(93.91%,94.67%,94.94%,and 94.96%)achieved when alternative systems based on diverse optimization techniques and the same dataset are *** proposed optimization techniques increase the effectiveness of the anomaly detection system by efficiently achieving high accuracy and reducing the computational load on IoT devices through the adaptive selection of active features.

关键词： Internet of Things security anomaly detection and prevention system artificial intelligence optimization techniques

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