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Gravitational form factors and nucleon spin structure

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Frontiers of physics 2016年第5期11卷 1-8页

作者： o.V. Teryaev Bogoliubov Laboratory of Theoretical Physics JINR 141980 Dubna Moscow Region Russia

Nucleon scattering by the classical gravitational field is described by the gravitational （energy- momentum tensor） form factors （GFFs）, which also control the partition of nucleon spin between the total angular momenta of quarks and gluons. The equivalence principle （EP） for spin dynamics results in the identically zero anomalous gravitomagnetic moment, which is the straightforward analog of its electromagnetic counterpart. The extended EP （ExEP） describes its （approximate） validity separately for quarks and gluons and, in turn, results in equal partition of the momentum and total angular momentum. It is violated in quantum electrodynamics and perturbative quantum chromodynamics （QCD）, but may be restored in nonperturbative QCD because of confinement and spontaneous chiral symmetry breaking, which is supported by models and lattice QCD calculations. It may, in principle, be checked by extracting the generalized parton distributions from hard exclu- sive processes. The EP for spin-1 hadrons is also manifested in inclusive processes （deep inelastic scattering and the Drell-Yan process） in sum rules for tensor structure functions and parton distributions. The ExEP may originate in either gravity-proof confinement or in the closeness of the GFF to its asymptotic values in relation to the mediocrity principle. The GFFs in time-like regions reveal some similarity between inflation and annihilation.

关键词： gravity form factors equivalence principle

Analysis of Sakiadis flow of nanofluids with viscous dissipation and Newtonian heating

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Applied Mathematics and Mechanics(English Edition) 2012年第12期33卷 1545-1554页

作者： o.D.MAKINDE Institute for Advance Research in Mathematical Modelling and Computations Cape Peninsula University of TechnologyP.O.Box 1906Bellville 7535South Africa

The combined effects of viscous dissipation and Newtonian heating on bound- ary layer flow over a moving flat plate are investigated for two types of water-based New- tonian nanofluids containing metallic or nonmetallic nanoparticles such as copper （Cu） and titania （Ti02）. The governing partial differential equations are transformed into ordinary differential equations through a similarity transformation and are solved numer- ically by a Runge-Kutta-Fehlberg method with a shooting technique. The conclusions are that the heat transfer rate at the moving plate surface increases with the increases in the nanoparticle volume fraction and the Newtonian heating, while it decreases with the increase in the Brinkmann number. Moreover, the heat transfer rate at the moving plate surface with Cu-water as the working nanofiuid is higher than that with Tio2-water.

关键词： Sakiadis flow nanofluid viscous dissipation Newtonian heating

Looking Back and Beyond Sendai:25 Years of International Policy Experience on Disaster Risk Reduction

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International Journal of Disaster Risk Science 2015年第1期6卷 1-7页

作者： Sálvano Briceo Science Committee Integrated Research on Disaster Risk(IRDR) Program of International Council for Science (ICSU)/International Social Science Council (ISSC)/United NationsInternational Strategy for Disaster Reduction (UNISDR)

The evolution in knowledge and application of disaster risk reduction in the 25 years of global cooperation on this issue has been uneven. While advances in knowledge have improved our understanding of the full nature of risk—the combination of hazards meeting vulnerability—the application of such knowledge has not been conducive to the development of institutional and technical mechanisms to address the full range of risk elements. Governance of risk(policies, legislation, and organizational arrangements) still focuses largely on preparing to respond to the hazards and planning for recovery. This leaves largely unattended the vulnerability component of risk, which is the only component on which change can be *** arrangements, risk assessments, early warning systems, and other institutional and technical capacities still concentrate on natural hazards and this is the main change that remains to be substantively addressed.

关键词： Climate change adaptation Disaster risk reduction Risk governance Risk management

Element diffusion ability in metasomatic agents and its effect on chemical characteristics of metasomatized peridotites

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Science China Earth Sciences 2006年第9期49卷 926-937页

作者： Y S o’Reilly GEMoC ARC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney N.S.W. 2109 Australia

Detailed in situ LM-ICPMS researches on the composite xenoliths from Yingfengling volcano of Leizhou Peninsula, South China, indicate that most incompatible trace elements of clino- pyroxenes in composite xenoliths decrease spatially from pyroxenites to distal lherzolites, and com- patible elements and HREE increase steeply. The increasing and decreasing rate is distinct for dif- ferent trace elements, which give rise to element chromatographic fractionation within metasomatized lherzolites. The element chromatographic fractionation result actually from the difference in element diffusive rate in melts or fluids percolating through wall-rock lherzolites. Based on element variation profiles in composite xenoliths this study indicates that Sr, Nb, La and Ce have the highest diffusive mobility, MREE-HREE are moderate, and Zr, Hf, Ti, Ga and Sc are very low in most cases. Higher diffusive rates of LREE than HREE would enlarge the REE fractionation of metasomatized peridotites, and lower diffusive rate of Zr, Hf and Ti relative to neighbor REEs with similar incompatibility would cause the relative depletion of these elements in metasomatized peridotites. Trace elements com- monly have a higher diffusive rate in fluid-rich infiltrating melt, which will weaken element chroma- tographic fractionation during the metasomatism. The range of mantle metasomatism caused by sili- cate melt intrusion is very limited, generally within tens of centimeters wide. The width of metasoma- tized wall-rock peridotites near the pyroxenite or horblendite veins was strictly controlled by both melt volume and chemical characteristics.

关键词： composite xenolith, metasomatism, chromatographic fractionation, diffusive rate, Leizhou Peninsula.

Recycling organic waste in managed tropical forest ecosystems:effects of arboreal litter types on soil chemical properties in Abeokuta, southwestern Nigeria

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Journal of Forestry Research 2019年第5期30卷 1903-1911页

作者： J.o.Azeez Department of Soil Science and Land Management Federal University of Agriculture Abeokuta

The aim of this study is to determine the influence of tree litters on soil nutrients in a managed forest in southwestern *** species tree clusters consisted of indigenous species:Gmelina arborea,Tectona grandis,Leucaena leucocephala,Bambusa vulgaris,Treculia africana,Anogeissus leiocarpus were selected and analyzed for their litter and soil chemical properties at 0–5 and 15–30 *** and *** litters have the highest nutrients,while *** and *** are the *** under ***,***,and *** are more acidic due to lower calcium and magnesium contents but have higher manganese and sulphur *** litters improved soil nitrogen,phosphorous,and micro-nutrients but depleted *** lignin and carbon appeared to hinder the release of some ***,potassium and copper are concentrated in the topsoil while others nutrients are not differentiated with soil *** is a positive correlation between litter chemistry and soil chemical *** was concluded that tree litter chemistry differs according to species but determines soil reaction and nutrient *** magnitude of the effect on soil properties is related to the quality of the organic litters.

关键词： Litter chemistry Nutrient stocks Soil chemical properties Tropical trees Biosystems

A Secure Intrusion Detection System in Cyberphysical Systems Using a Parameter-Tuned Deep-Stacked Autoencoder

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Computers, Materials & Continua 2021年第9期68卷 3915-3929页

作者： Nojood o.Aljehane College of Computer Science and Information Technology University of TabukTabukSaudi Arabia

Cyber physical systems(CPSs)are a networked system of cyber(computation,communication)and physical(sensors,actuators)elements that interact in a feedback loop with the assistance of human ***,CPSs authorize critical infrastructures and are considered to be important in the daily lives of humans because they form the basis of future smart *** utilization of CPSs,however,poses many threats,which may be of major significance for *** security issues in CPSs represent a global issue;therefore,developing a robust,secure,and effective CPS is currently a hot research *** resolve this issue,an intrusion detection system(IDS)can be designed to protect *** the IDS detects an anomaly,it instantly takes the necessary actions to avoid harming the *** this study,we introduce a new parameter-tuned deep-stacked autoencoder based on deep learning(DL),called PT-DSAE,for the IDS in *** proposed model involves preprocessing,feature extraction,parameter tuning,and ***,data preprocessing takes place to eliminate the noise present in the ***,a DL-based DSAE model is applied to detect anomalies in the *** addition,hyperparameter tuning of the DSAE takes place using a search-and-rescue optimization algorithm to tune the parameters of the DSAE,such as the number of hidden layers,batch size,epoch count,and learning *** assess the experimental outcomes of the PT-DSAE model,a series of experiments were performed using data from a sensor-based ***,a detailed comparative analysis was performed to ensure the effective detection outcome of the PT-DSAE *** experimental results obtained verified the superior performance on the applied data over the compared methods.

关键词： Cyberphysical system intrusion detection system autoencoder cybersecurity

Benchmark assessment of performance indices of a selection of hybrid nanofluids in a hybrid photovoltaic/thermal system

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Clean Energy 2022年第2期6卷 247-270页

作者： o.M.Amoo R.o.Fagbenle M.o.oyewola Department of Mechanical Engineering University of IbadanIbadanOyo StateNigeria School of Mechanical Engineering Fiji National UniversityFiji

This research is a study assessing the performance of hybrid nanofluids in hybrid photovoltaic(PV)-thermal *** study addresses 10 hybrid nanofluids applied to hybrid PV-thermal *** transition to carbon-free energy can mitigate the worst effects of climate change,ensuring that global sustainability is *** energy is now responsible for one-third of the global capacity,of which 20%is attributed to solar *** continue to be economically viable,with declining costs driving *** study aims to compare the yearly performances of a model hybrid PV-thermal system using 10 different hybrid *** nanofluids constitute two or more dissimilar materials stably suspended in a base fluid(***).MATLAB and CoMSoL Multiphysics®computational fluid dynamics software are employed together for the benchmarking assessment with good agreement *** fluid inlet temperatures(Tin∈[300,360]K),nanofluid volume concentrations(φ∈[0,4]%)and storage-tank volumes(V∈[50,300]L)were *** meteorological data applied were those for Lagos,Nigeria(6°27’55.5192”N,3°24’23.2128”E).The assessment based on analytical-numerical solutions reveals that the thermal enhancement by hybrid nanofluids ranges from 6.7%(graphene oxide[Go]-multiwalled carbon nanotube[MWCNT]/water)to 7%(Zno-Mn-ZnFe2o4/water)forφ=2%and V=300 *** yearly exergy efficiency ranges from 2.8%(Zno-Mn-ZnFe2o4/water)to 2.9%(Go-MWCNT/water),also forφ=2%and V=300 *** findings have implications for a vast range of industrial processes,expanding the knowledge that is critical to a sustainable future.

关键词： energy transformation hybrid photovoltaic-thermal(PV/T)system hybrid nanofluids CoMSoL Multiphysics® MATLAB enhancements

Rice Yield Estimation by Integrating Remote Sensing with Rice Growth Simulation Model

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Pedosphere 2004年第4期14卷 519-526页

作者： o.ABoU-ISMAIL Institute

Since remote sensing can provide information on the actual status of an agricultural crop, the integration between remote sensing data and crop growth simulation models has become an important trend for yield estimation and *** main objective of this research was to combine a rice growth simulation model with remote sensing data to estimate rice grain yield for different growing seasons leading to an assessment of rice yield at regional levels. Integration between NoAA (National oceanic and Atmospheric Administration) AVHRR (Advanced Very High Resolution Radiometer) data and the rice growth simulation model oRYZA1 to develop a new software, which was named as Rice-SRS Model, resulted in accurate estimates for rice yield in Shaoxing, China, with an estimation error reduced to 1.03% and 0.79% over-estimation and 0.79% under-estimation for early, single and late season rice, respectively. Selecting suitable dates for remote sensing images was an important factor which could influence estimation accuracy. Thus, given the different growing periods for each rice season, four images were needed for early and late rice, while five images were preferable for single season *** rice yield using two or three images was possible, however, if images were obtained during the panicle initiation and heading stages.

关键词： remote sensing rice growth simulation model rice yield estimation

Sedimentology and foraminiferal paleoecology of the exposed oligocene-Miocene ogwashi-Asaba Formation in Issele-Uku area,Anambra Basin,southern Nigeria:A paleoenvironmental reconstruction

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Journal of Palaeogeography 2022年第4期11卷 618-628页

作者： J.A.Adeoye V.o.Jolayemi S.o.Akande Department of Geology and Mining Ibrahim Badamasi Babangida UniversityLapai 911101Niger StateNigeria Department of Geology and Mineral Sciences University of IlorinIlorin 240101Kwara StateNigeria

Sedimentological and foraminiferal paleoecological studies were carried out for the oligocene-Miocene ogwashi-Asaba Formation of the Anambra Basin at the Issele-Uku area in southern Nigeria,to reconstruct *** pattern of rock successions and textural characteristics suggest the prevalence of fluvio-deltaic setting during the formation of lignites and clastic rocks of ogwashi-Asaba *** benthic foraminiferal species such as Ammotium sp.,Textularia sp.,Gavelinella sp.,Milliamina sp.,Reophax sp.,Bolivina sp.,Eponides sp.,Pseudobolivina *** Lenticulina *** the shale units whereas the planktonic forms are *** these species have very low population and diversity in the shales,which could be due to the presence of harsh conditions such as low oxygen level and scarcity of food,leading to poor *** assessments of benthic foraminifera's habitat suggest middle-to-inner neritic marine environment for the *** results suggest fluvial environment for the sandstone and deltaic for the *** ogwashi-Asaba Formation in Issele-Uku area of Anambra Basin,southern Nigeria,therefore,have records of shallow marine,and fluvio-deltaic paleoenvironments.

关键词： Foraminiferal Sedimentology ogwashi-Asaba Formation Anambra Basin Paleoecology