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A Digitized Weather Radar in gansu Province and a Simple Radar-Raingauge Comparison

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高原气象 1987年第2期 97-110页

作者： M.Blaskovic,A.Bellon,g.l.austin,Q.M.Cai Mcgill Radar Weather Observatory Montreal Quebec Canada H2X 1CO Mcgill Radar Weather Observatory Montreal Quebec Canada H2X 1CO Mcgill Radar Weather Observatory Montreal Quebec Canada H2X 1CO lanzhou Institute of Plateau Atmospheric Physics Academia Sinica lanzhou gansu

An on-line computer processing system was added to the lanzhouInstitute’*** of digitized weather radar isdiscussed and a preliminary examination of the rain-measuring capabilityof the radar-computer system is made.

关键词： In A Digitized Weather Radar in gansu Province and a Simple Radar-Raingauge Comparison

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数字天气雷达监测暴雨洪水研究

气象科技 1990年第1期18卷 23-29页

作者：徐宝祥蔡启铭 C.A.Madramootoo g.l.austin 中国科学院兰州大气所中国科学院南京地理所加拿大麦吉尔大学

从加强水资源管理和减少洪水危害来看.应用数字天气雷达定量测定大范围区域降水量,并建立降雨量对水文参量的预报方程是有应用价值的方案.统计表明,在建立预报方程时应区分不同类型降水.经过仔细标定的数字化天气雷达,在探测区内少数地... 详细信息

从加强水资源管理和减少洪水危害来看.应用数字天气雷达定量测定大范围区域降水量,并建立降雨量对水文参量的预报方程是有应用价值的方案.统计表明,在建立预报方程时应区分不同类型降水.经过仔细标定的数字化天气雷达,在探测区内少数地面雨量计的校准下,可以30%(层状云降水)和60%(混合型降水)的精度实时监测降雨风暴并做出外推形势预报.与洪水关系密切的过程降雨总量之测量误差对不同类型降水均在±40%之内.用双线偏振等特种天气雷达系统,并考虑截流地表特性和地面蒸发等因子,则可进一步提高测量预报精度.

关键词：天气雷达暴雨洪水探测区加强水资源管理地面蒸发预报精度降雨总量区域降水量预报方程形势预报

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数字化3cm天气雷达定量测量降水的结果和讨论

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高原气象 1988年第4期 330-344页

作者：薛震刚蔡启铭徐宝祥 g.l.austin 中国科学院兰州高原大气物理研究所 Mcgill University Canada

本文讨论了3cm天气雷达在兰州地区定量测量降水及其精度;分析了不同降水类型和衰减等对测量的影响;讨论了地面雨量计订正雷达测量值的方法和效果。

关键词：数字化雷达雷达测雨等高平显

No evidence of predator odor avoidance in a North American bird community

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Avian Research 2024年第1期15卷 133-138页

作者： austin Dotta Batur Yaman Alex Van Huynh Department of Biology DeSales University2755 Station AvenueCenter ValleyPAUSA

Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian *** studies investigating predator avoidance behaviors in response to predator odor cues have produced mixed results across species and *** we assess if a community of birds in eastern Pennsylvania displays avoidance behaviors towards predator odor cues in a natural foraging *** use clay caterpillars to measure foraging activity by birds in the presence of predator(bobcat)urine,non-predator(rabbit)urine,and water controls in two different environmental contexts(field ***).Although we detected a weak trend for birds to forage less at predator urine-treated sites,we found no significant difference in avian foraging between the site *** did find that foraging rates between environmental contexts changed significantly over the course of the experiment,with forest sites showing decreasing foraging rates and field sites showing increasing foraging *** results reinforce the published literature that avoidance of predator odors by birds may not be ubiquitous across contexts and species.

关键词： Foraging Odor Olfaction Predation Predator-avoidance

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First-principles calculation on the electronic structures, phonon dynamics, and electrical conductivities of Pb_(10)(PO_(4))_(6O) and Pb_(9)Cu(PO_(4))_(6O) compounds

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Journal of Materials Science & Technology 2024年第6期173卷 218-224页

作者： l.Y.Hao E.g.Fu State Key laboratory of Nuclear Physics and Technology Department of Technical PhysicsSchool of PhysicsPeking UniversityBeijing 100871China

Superconducting materials with high critical temperature have the potential to revolutionize many fields,including military,electronic communications,and power ***,scientists around the world have been tirelessly working with the ultimate goal of achieving high-temperature *** 2023,a preprint by lee et *** South Korea claimed the discovery of ultra-high-temperature superconductivity with a critical temperature of up to 423 K in Cu-doped lead-apatite(lK-99)(arXiv:2307.12008,arXiv:2307.12037),which caused a worldwide sensation and ***,the electronic structures,phonon dynamics,and electrical conductivities of lK-99 and its parent compound lead-apatite have been calculated using first-principles *** results show that the lead-apatite compound and the lK-99 compound are insulator and half-metal *** flat band characteristic is consistent with previous *** electrical conductivity of the lK-99 compound shows two extreme points,and the electrical conductivity along the C-axis increases significantly after 400 *** phonon dispersion spectra of the compounds were investigated,demonstrating their dynamic instability.

关键词： Superconductivity lK-99 lead-apatite First-principles calculation

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite Buffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： l.Iniya B.Sivakumar g.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

Combustion characteristics of low-quality lignite for different bed material sphericities in a circulating fluidized bed boiler:A numerical study

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Particuology 2024年第7期90卷 364-382页

作者： Barış gürel gülşah Karaca Dolgun Osman İpek Ali Keçebaş Department of Mechanical Engineering Engineering FacultySüleyman Demirel UniversityÇünürIspartaTurkey Department of Energy Systems Engineering Technology FacultyMuğla SıtkıKoçman UniversityKötekliMenteşeMuğlaTurkey

This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key ***,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case of glI-Tunçbilek *** levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure *** combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole *** NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with Ilgın lignite showcasing low NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and ***,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power.

关键词： Circulating fluidized bed boiler Computational particle fluid dynamics method Particle sphericity ratios NO_(x)and SO_(2)emissions Energy production efficiency

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 197-216页

作者： C.g.PAVITHRA B.J.gIREESHA M.l.KEERTHI Department of Pg Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTM) trihybrid nanofluid magnetic field

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Mechanical Behavior of Panels Reinforced with Orthogonal Plant Fabrics: Experimental and Numerical Assessment

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Journal of Renewable Materials 2024年第10期12卷 1791-1810页

作者： Martha l.Sánchez g.Capote Universidad Militar Nueva granada Programa de Ingeniería CivilBogotá110111Colombia Facultad de Ciencias Departamento de FísicaUniversidad Nacional de ColombiaBogotá111321Colombia

The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional *** production of cement,steel,and other conventional materials impacts both ecosystems and human health,increasing the demand for ecological and biodegradable *** this paper,we analyze the properties of panels made from a combination of plant fibers and castor oil resin,analyzing the viability of their use as construction *** the research,orthogonal fabrics made with waste plant fibers supplied by a company that deals with the manufacture of furniture and craft products were *** fabrics were made with strips of plant fibers of the Calamus rotang,Bambusa vulgaris,Heteropsis flexuosa,and Salix viminalis *** improve their compatibility with the castor oil resin,a cold argon plasma treatment was *** effect of the treatment on the properties of the fibers and the panels was *** density,water absorption capacity,and swelling percentage were ***,compression,static bending,and linear buckling tests were carried *** study found that panels made with treated fiber fabrics exhibited a reduction of approximately 10%in absorption capacity and up to 35%in swelling percentage *** made with Bambusa vulgaris fabrics exhibited the highest strength and stiffness *** models were constructed using commercial finite element *** comparing the numerical results with the experimental ones,differences of less than 15%were seen,demonstrating that the models allow adequately predicting the analyzed *** comparing the values obtained with the characteristic values of oriented strand board,the results suggest that panels made with unconventional materials could replace commercial panels traditionally made with wood-based fibers and particles and other composite materials in several applications in th

关键词： Unconventional materials nonstructural panels plantﬁbers surface treatment physical properties mechanical properties