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Groundwater recharge rates and surface runoff response to land use and land cover changes in semi-arid environments

Ecological Processes 2016年第1期5卷 195-215页

作者： S.O.Owuor k.butterbach-bahl A.C.Guzha M.C.Rufino D.E.Pelster E.Diaz-Pines L.Breuer Institute of Meteorology and Climate Research Atmospheric Environmental Research(IMK-IFU)Karlsruhe Institute of Technology(KIT)Kreuzeckbahnstr.1982467 Garmisch-PartenkirchenGermany International Livestock Research Institute(ILRI) Old Naivasha Rd.P.O.Box 30709-00100NairobiKenya United States Forest Service c/o CIFORWorld Agroforestry CentreUnited Nations Avenue GigiriP.O.Box 30677-00100NairobiKenya Center for International Forestry Research(CIFOR) C/o World Agroforestry CentreUnited Nations Avenue GigiriP.O.Box 30677-00100NairobiKenya Institute for Landscape Ecology and Resources Management(ILR) Research Centre for BioSystemsLand Use and Nutrition(iFZ)Justus Liebig University GiessenHeinrich-Buff-Ring 2635392 GiessenGermany Centre for International Development and Environmental Research(ZEU) Justus Liebig University GiessenGiessenGermany

The effects of land use and land cover(LULC)on groundwater recharge and surface runoff and how these are affected by LULC changes are of interest for sustainable water resources ***,there is limited quantitative evidence on how changes to LULC in semi-arid tropical and subtropical regions affect the subsurface components of the hydrologic cycle,particularly groundwater *** water resource management in these regions requires conclusive evidence and understanding of the effects of LULC changes on groundwater recharge and surface *** reviewed a total of 27 studies(2 modeling and 25 experimental),which reported on pre-and post land use change groundwater recharge or surface runoff magnitude,and thus allowed to quantify the response of groundwater recharge rates and runoff to *** between initial and subsequent LULC indicate that forests have lower groundwater recharge rates and runoff than the other investigated land uses in semi-arid tropical/subtropical *** of bare land induces a decrease in groundwater recharge from 42% of precipitation to between 6 and 12% depending on the final *** forests are cleared for rangelands,groundwater recharge increases by 7.8±12.6%,while conversion to cropland or grassland results in increases of 3.4±2.5 and 4.4±3.3%,*** of bare land to cropland results in surface runoff reductions of between 5.2 and 7.3%.The conversion of forest vegetation to managed LULC shows an increase in surface runoff from 1 to 14.1% depending on the final *** runoff was reduced from 2.5 to 1.1% when grassland is converted to forest *** there is general consistency in the results from the selected case studies,we conclude that there are few experimental studies that have been conducted in tropical and subtropical semi-arid regions,despite that many people rely heavily on groundwater for their ***,there is an urgent need to increase th

关键词： Groundwater recharge rate Infiltration Surface runoff Semi-arid Land use change Land cover change

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REGIONAL ASSESSMENT OF SOIL NITROGEN MINERALIZATION IN DIVERSE CROPLAND OF A REPRESENTATIVE INTENSIVE AGRICULTURAL AREA

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Frontiers of Agricultural Science and Engineering 2023年第4期10卷 530-540页

作者： Peng XU Minghua ZHOU Bo ZHU klaus butterbach-bahl key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChineseAcademyof SciencesChengdu610041China Institute for Meteorology and Climate Research Atmospheric Environmental Research(IMK-IFU)Karlsruhe Institute of Technology(KIT)Garmisch-Partenkirchen 82467Germany

Soil nitrogen mineralization(Nmin)is a key process that converts organic N into mineral N that controls soil N availability to ***,regional assessments of soil Nmin in cropland and its affecting factors are lacking,especially in relation to variation in *** this study,a 4-week incubation experiment was implemented to measure net soil Nmin rate,gross nitrification(Nit)rate and corresponding soil abiotic properties in five field soils(A-C,maize;D,flue-cured tobacco;and E,vegetables;with elevation decreasing from A to E)from different altitudes in a typical intensive agricultural area in Dali City,Yunnan Province,*** results showed that soil Nmin rate ranged from 0.10 to 0.17 mg·kg^(-1)·d^(-1)N,with the highest value observed in field E,followed by fields D,C,B,and A,which indicated that soil Nmin and Nit rates varied between fields,decreasing with *** soil Nit rate ranged from 434.2 to 827.1μg·kg^(-1)·h^(-1)N,with the highest value determined in field D,followed by those in fields E,C,B,and *** rates of soil Nmin and Nit were positively correlated with several key soil parameters,including total soil N,dissolved organic carbon and dissolved inorganic N across all fields,which indicated that soil variables regulated soil Nmin and Nit in cropland *** addition,a strong positive relationship was observed between soil Nmin and *** findings provide a greater understanding of the response of soil Nmin among cropland fields related to spatial *** is suggested that the soil Nmin from cropland should be considered in the evaluation of the N transformations at the regional scale.

关键词： cropland gross nitrification rate regulatory factors soil nitrogen mineralization spatial variation

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Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts

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Green Energy & Environment 2024年第4期9卷 777-788页

作者： A.k.k.Vikla k.koichumanova Songbo He k.Seshan Joint International Research Laboratory of Circular Carbon Nanjing Tech UniversityNanjing211816China Faculty of Science and Technology University of Twente7500 AE EnschedeThe Netherlands CoRe Pro 9723 BL GroningenThe Netherlands

Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction *** this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 *** them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst *** the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst *** proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.

关键词： APR Hydroxyacetone TOF Bio-based H_(2) Support effect

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Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： Mohammad Saifullah Vinay k.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

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Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k JAMES Jintu kIM Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

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Impact of Fin Arrangement on Heat Transfer and Melting Characteristics of Phase Change Material

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Journal of Thermal Science 2024年第2期33卷 435-456页

作者： Arun UNIYAL Yogesh k.PRAJAPATI Department of Mechanical Engineering National Institute of Technology UttarakhandSrinagar(Garhwal)246174India Department of Mechanical Engineering BIT SindriDhanbadJharkhand828123India

Present work investigates the heat transfer and melting behaviour of phase change material(PCM) in six enclosures(enclosure-1 to 6) filled with paraffin *** enclosures are equipped with distinct arrangements of the fins while keeping the fin's surface area equal in each *** analysis has been presented to recognize the suitable fin arrangements that facilitate improved heat transfer and melting rate of the *** wall of the enclosure is maintained isothermal for the temperature values 335 k,350 k and 365 *** length of the enclosure including fins is ranging between 0 and *** have been illustrated through the estimation of important performance parameters such as energy absorbing capacity,melting rate,enhancement ratio,and Nusselt *** has been found that melting time(to melt 100% of the PCM) is 60.5%less in enclosure-2(with two fins of equal length) as compared to the enclosure-1,having no *** the fin surface area equal,if the longer fin is placed below the shorter fin(enclosure-3),melting time is further decreased by 14.1% as compared to ***,among all the configurations,enclosure-6 with wire-mesh fin structure exhibits minimum melting time which is 68.4% less as compared to the *** on the findings,it may be concluded that fins are the main driving agent in the enclosure to transfer the heat from heated wall to the *** design and positioning of the fins improve the heat transfer rate followed by melting of the PCM in the entire area of the *** of the favourable vortices and natural convection current in the enclosure accelerate the melting phenomenon and help to reduce charging time.

关键词： phase change material enclosure fin melting fraction energy storage heat transfer

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MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar k.P.Vijayakumar k.Pradeep A.Balasundaram School of Computer Science and Engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber Physical Systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is *** the production and quality of the mangoes are hampered by many *** diseases need to be effectively controlled and ***,a quick and accurate diagnosis of the disorders is *** convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification ***,it requires large training datasets and several parameters that need careful *** proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango *** model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning *** data loader also builds mini-batches for training the models to reduce training ***,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 *** the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset

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Long Term X-Ray Spectral Variations of the Seyfert-1 Galaxy Mrk 279

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Research in Astronomy and Astrophysics 2024年第6期24卷 307-314页

作者： k.Akhila Ranjeev Misra Savithri H.Ezhikode k.Jeena Department of Physics Providence Women’s CollegeUniversity of CalicutKerala 673009India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PB No.4GaneshkhindPune 411007India Department of Physics and Electronics CHRIST(Deemed to be University)Hosur Main RoadBangalore 560029India

We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–*** use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the *** X-ray spectrum can be modeled as a double Comptonization along with the presence of neutral Fe kαline emission,at all *** determined the source’s X-ray flux and luminosity at these different *** find significant variations in the source’s flux *** also investigate the variations in the source’s spectral components during the observation *** find that the photon index and hence the spectral shape follow the variations only over longer time *** probe the correlations between fluxes of different bands and their photon indices,and found no significant correlations between the parameters.

关键词： galaxies:Seyfert galaxies:individual(Mrk 335) X-rays:galaxies

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Applicability limits of the DAX test in plastic bonded explosives

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Defence Technology（防务技术） 2024年第6期36卷 64-70页

作者： Martin künzel Jindrich kucera Jiri Pachman OZM Research Bliznovice 32Hrochuv Tynec 53862Czech Republic Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceStudentska 95Pardubice 53210Czech Republic

The Disc Acceleration e Xperiment(DAX)is one of the most recent experimental methods of performance characterization of new energetic materials.A cylindrical explosive charge accelerates a thin metallic disc and its velocity is measured continuously using photonic Doppler *** detonation velocity is measured *** DAX test can be used to obtain the Chapman-Jouguet(CJ)detonation pressure and to describe detonation products expansion using reduced amount of explosive.A series of DAX tests was performed at various charge diameters and disc thicknesses with Semtex 1 A plastic bonded explosive and sensitized *** DAX-like evaluation was also applied to previously measured data of Semtex 1A and A-IX-1 *** optimum disc thickness is determined by the disc to explosive mass ratio of *** repeatability of the Semtex 1 A detonation pressure results is about four times lower compared to the pressed and liquid explosives.

关键词： Flyer plate Detonation pressure Photonic Doppler velocimetry Semtex

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Hybrid Prairie Dog and Beluga Whale Optimization Algorithm for Multi-Objective Load Balanced-Task Scheduling in Cloud Computing Environments

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China Communications 2024年第7期21卷 307-324页

作者： k Ramya Senthilselvi Ayothi Department of Computer Science and Engineering SRM Institute of Science and TechnologyRamapuramChennaiTamil Nadu 600089India

The cloud computing technology is utilized for achieving resource utilization of remotebased virtual computer to facilitate the consumers with rapid and accurate massive data *** utilizes on-demand resource provisioning,but the necessitated constraints of rapid turnaround time,minimal execution cost,high rate of resource utilization and limited makespan transforms the Load Balancing(LB)process-based Task Scheduling(TS)problem into an NP-hard optimization *** this paper,Hybrid Prairie Dog and Beluga Whale Optimization Algorithm(HPDBWOA)is propounded for precise mapping of tasks to virtual machines with the due objective of addressing the dynamic nature of cloud *** capability of HPDBWOA helps in decreasing the SLA violations and Makespan with optimal resource *** is modelled as a scheduling strategy which utilizes the merits of PDOA and BWOA for attaining reactive decisions making with respect to the process of assigning the tasks to virtual resources by considering their priorities into *** addresses the problem of pre-convergence with wellbalanced exploration and exploitation to attain necessitated Quality of Service(QoS)for minimizing the waiting time incurred during TS *** further balanced exploration and exploitation rates for reducing the makespan during the task allocation with complete awareness of VM *** results of the proposed HPDBWOA confirmed minimized energy utilization of 32.18% and reduced cost of 28.94% better than approaches used for *** statistical investigation of the proposed HPDBWOA conducted using ANOVA confirmed its efficacy over the benchmarked systems in terms of throughput,system,and response time.

关键词： Beluga Whale Optimization Algorithm(BWOA) cloud computing Improved Hopcroft-karp algorithm Infrastructure as a Service(IaaS) Prairie Dog Optimization Algorithm(PDOA) Virtual Machine(VM)

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