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感应磁场和变热导率对二级流体驻点流动的影响

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Journal of Central South University 2021年第11期28卷 3381-3390页

作者： A.A.KHAN S.ILYAS T.AbbAS R.ELLAHI Department of Mathematics and Statistics International Islamic UniversityIslamabad 44000Pakistan Departrment of Mathematics Division of Science and TechnologyUniversity of EducationLahore 54770Pakistan Fulbright Fellow Department of Mechanical Engineering University of California RiversideRiverside 92521USA

本文研究变热导率和感应磁场冲击作用下具有线性拉伸特性的二级流体驻点输运问题。通过适当的变换,将非线性粒子微分方程组转化为常微分方程组。用最优同伦分析方法对所得方程进行求解。通过图解研究相关参数对表面摩擦系数、温度、感... 详细信息

本文研究变热导率和感应磁场冲击作用下具有线性拉伸特性的二级流体驻点输运问题。通过适当的变换,将非线性粒子微分方程组转化为常微分方程组。用最优同伦分析方法对所得方程进行求解。通过图解研究相关参数对表面摩擦系数、温度、感应磁场、速度和局部努塞尔数的影响。利用MAtLAB软件中内置的bvp4c技术对得到的级数解进行收敛和残差处理。结果表明:随着磁场参数的增大,表面摩擦系数也随拉伸比的增大而增大。为验证结果的有效性,我们与文献进行对比,发现本研究与现有文献结果非常一致。

关键词：驻点变导热系数感应磁场二级流体

Machine learning enabled identification and real-time prediction of living plants’ stress using terahertz waves

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Defence technology（防务技术） 2022年第8期18卷 1330-1339页

作者： Adnan Zahid Kia Dashtipour Hasan T.AbbAS Ismail Ben Mabrouk Muath Al-Hasan Aifeng Ren Muhammad A.Imran Akram Alomainy Qammer H.abbasi School of Engineering and Physical Science Heriot-Watt UniversityEdinburghEH144ASUK James Watt School of Engineering University of GlasgowGlasgowG128QQUK College of Engineering Al-Ain UniversityAbu DhabiUnited Arab Emirates School of Electronic Engineering Xidian UniversityXi'anShaanxiChina School of Electronic Engineering and Computer Science Queen Mary University of LondonLondonUK

Considering the ongoing climate transformations, the appropriate and reliable phenotyping information of plant leaves is quite significant for early detection of disease, yield improvement. In real-life digital agricultural environment, the real-time prediction and identification of living plants leaves has immensely grown in recent years. Hence, cost-effective and automated and timely detection of plans species is vital for sustainable agriculture. this paper presents a novel, non-invasive method aiming to establish a feasible, and viable technique for the precise identification and observation of altering behaviour of plants species at cellular level for four consecutive days by integrating machine learning (ML) and tHz with a swissto12 materials characterization kit (MCK) in the frequency range of 0.75 to 1.1 tHz. For this purpose, measurements observations data of seven various living plants leaves were determined and incorporate three different ML algorithms such as random forest (RF), support vector machine, (SVM), and K-nearest neighbour (KNN). the results demonstrated that RF exhibited higher accuracy of 98.87% followed by KNN and SVM with an accuracy of 94.64% and 89.67%, respectively, for precise detection of different leaves by observing their morphological features. In addition, RF outperformed other classifiers for determination of water-stressed leaves and having an accuracy of 99.42%. It is envisioned that proposed study can be proven beneficial and vital in digital agriculture technology for the timely detection of plants species to significantly help in mitigate yield and economic losses and improve crops quality.

关键词： terahertz sensing Plants health Machine learning

Biochar Application Improves the Drought tolerance in Maize Seedlings

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 379-388页

作者： A.Sattar A.Sher M.Ijaz M.Irfan M.Butt T.AbbAS S.Hussain A.abbas M.S.Ullah M.A.Cheema College of Agriculture Bahauddin Zakariya University Bahadur Sub-CampusLayyah31200Pakistan Department of Agronomy Faculty of Agriculture Science and Technology Bahauddin Zakariya UniversityMultan60800Pakistan Faculty of Pharmaceutical Sciences Government College UniversityFaisalabad38000Pakistan School of Science and the Environment Grenfell Campus Memorial University of NewfoundlandCorner Brook2000A2H 5G4Canada

Application of biochar to agricultural soils is mostly used to improve soil fertility.Experimental treatments were comprised of two factors:i)drought at two level,i.e.,80%and 40%water holding capacity(WHC)which was maintained on gravimetric basis ii)three levels of biochar i.e.,control,2 t ha^(-1) and 4 t ha^(-1) added to soil.Experimentation was done to examine potential of biochar application to enhance the growth attributes,water relations,photosynthetic pigments and antioxidants activities in maize(Zea mays L.)seedlings.Results of study revealed that biochar application increased the growth qualities(total seedlings biomass,dry weight of shoot and root,shoot length and root length).In addition;contents of photosynthetic pigments(chlorophyll a,b,a+b and a/b),water relation(relative water contents,turgor potential,osmotic potential and water potential)were improved significantly due to addition of biochar.Addition of 4 t ha^(-1) biochar led to significant rise activity of enzymatic antioxidant catalase(CAt),superoxide dismutase(SOD)and peroxidase(POD)in leaf of maize seedling sunder drought as well as well watered circumstances.However,biochar applied at the rate 4 t ha^(-1) improved the all the physiological and biochemical attributes in maize seedlings under drought.From the results it was concluded that biochar application is an efficient way to alleviate adverse effect of drought stress on maize.In drought prone areas,long term impacts of biochar on production of maize and properties of soil could be recommended as upcoming shove.

关键词： Antioxidants biochar drought stress water relations chlorophyll contents

Applying the spectral stochastic finite element method in multiple-random field RC structures

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Frontiers of Structural and Civil Engineering 2022年第4期16卷 434-447页

作者： abbas YAZDANI Civil Engineering Department University of Sistan and BaluchestanZahedan 98167-45845Iran

this paper uses the spectral stochastic finite element method(SSFEM)for analyzing reinforced concrete(RC)beam/slab problems.In doing so,it presents a new framework to study how the correlation length of a random field(RF)with uncertain parameters will affect modeling uncertainties and reliability evaluations.It considers:1)different correlation lengths for uncertainty parameters,and 2)dead and live loads as well as the elasticity moduli of concrete and steel as a multi-dimensional RF in concrete structures.to show the SSFEM’s efficiency in the study of concrete structures and to evaluate the sensitivity of the correlation length effects in evaluating the reliability,two examples of RC beams and slabs have been investigated.According to the results,the RF correlation length is effective in modeling uncertainties and evaluating reliabilities;the longer the correlation length,the greater the dispersion range of the structure response and the higher the failure probability.

关键词： uncertainty spectral stochastic finite element method correlation length reliability assessment reinforced concrete beam/slab

A Model‑Based Battery Charging Optimization Framework for Proper trade‑offs Between time and Degradation

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Automotive Innovation 2023年第2期6卷 204-219页

作者： Sean Appleton abbas Fotouhi Advanced Vehicle Engineering Centre Cranfield UniversityCollege RoadCranfield MK430ALUK

this study aims at developing an optimization framework for electric vehicle charging by considering different trade-offs between battery degradation and charging time.For the first time,the application of practical limitations on charging and cooling power is considered along with more detailed health models.Lithium iron phosphate battery is used as a case study to demonstrate the effectiveness of the proposed optimization framework.A coupled electro-thermal equivalent circuit model is used along with two battery health models to mathematically obtain optimal charging current profiles by considering stress factors of state-of-charge,charging rate,temperature and time.the optimization results demonstrate an improvement over the benchmark constant current–constant voltage(CCCV)charging protocol when considering both the charging time and battery health.A main difference between the optimal and the CCCV charging protocols is found to be an additional ability to apply constraints and adapt to initial conditions in the proposed optimal charging protocol.In a case study,for example,the‘optimal time’charging is found to take 12 min while the‘optimal health’charging profile suggests around 100 min for charging the battery from 25 to 75%state-of-charge.Any other trade-off between those two extreme cases is achievable using the proposed charging protocol as well.

关键词： Charging optimization Battery degradation Electro-thermal equivalent circuit model Electric vehicles Lithium iron phosphate

Different approaches for patent ductus arteriosus in premature infants using acetaminophen

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World Journal of Pediatrics 2022年第4期18卷 243-250页

作者： Aimann Surak Amish Jain abbas Hyderi Northern Alberta Neonatal Program Royal Alexandra Hospital Site NICU DTC 5027Stollery Children HospitalUniversity of Alberta10240 Kingsway NWEdmontonAB T5H 3V9Canada Department of Pediatrics Mount Sinai HospitalUniversity of TorontoTorontoONCanada

Background Acetaminophen use for pharmacological treatment of hemodynamically significant patent ductus arteriosus(hsPDA)in preterm infants is becoming more popular with emerging evidence that it is effective as well as safe alternative for other agents used to close hsPDA.Data sources We performed a narrative review of literature about pharmacological treatment of PDA using acetaminophen.Results Acetaminophen was used as a prophylaxis,symptomatic,targeted,and a rescue approach.Conclusions It appears that acetaminophen could be used in different approaches to close the hsPDA.Long-term outcomes of acetaminophen exposure early in life still lack certainty.

关键词： Acetaminophen Ligation Patent ductus arteriosus Preterm

Entropy generation for mixed convection flow in vertical annulus with two regions hydromagnetic viscous and Cu-Ag water hybrid nanofluid through porous zone: a comparative numerical study

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Propulsion and Power Research 2022年第3期11卷 401-415页

作者： t.Rahim J.Hasnain N.Abid Z.abbas Department of Mathematics The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Computer Sciences Bahria UniversityIslamabad44000Pakistan

the primary determination of this study is a numerical investigation of the entropygeneration (EG) in the steady two-region flow of viscous fluid and hybrid nanofluid (NF) in along-infinite vertical annulus having a clear region as well as porous media. Stoke’s and single-phase NF models are used to study the viscous fluid and hybrid nanofluid (HNF) heat transferdevelopments, respectively. two types of nanoparticles are taken, such as copper (Cu) and sil-ver (Ag) within base fluid water to make it a HNF. Darcy-Brinkman law is also used to examinethe flow through the porous zone in the annulus. Necessary quantities have been used in thesystem of equations to transfer them into non-dimensional forms. For momentum and energytransport, the numerical results are evaluated for various model parameters and are examinedvia the shooting method in MAtHEMAtICA. It is noted that the momentum and energy trans-port are more significant when two immiscible fluids in a clear vertical annulus are taken. thefindings also indicate that two-phase momentum and heat flow are greater when a NF is used in Region-II and lower when a HNF is used. the temperature (in Region-II) falls with a high na-nomaterials volume fraction (see Figure 4) while it is increased when the Hartman number isincreased. Moreover, velocity declines with increment in nanomaterials volume fraction. thus,higher thermal conductivity can be accomplished by using a magnetic field.

关键词： two-phase flow Hybrid nanofluid Viscous fluid Porous zone Vertical annulus Entropy generation

Is there a need for universal double reflex testing of HBsAg-positive individuals for hepatitis D infection?

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World Journal of Hepatology 2024年第3期16卷 300-303页

作者： Zaigham abbas Minaam abbas Department of Hepatogastroenterology and Liver transplantation Dr.Ziauddin University HospitalKarachi 75600SindhPakistan Department of Medicine University of CambridgeCambridge CB20SPUnited Kingdom

Hepatitis D virus(HDV)can infect HBsAg-positive individuals,causing rapid fibrosis progression,early decompensation,increased hepatocellular carcinoma risk,and higher mortality than hepatitis B virus(HBV)mono-infection.Most countries lack high-quality HDV prevalence data,and the collection techniques employed often bias published data.In recent meta-analyses,HDV prevalence in HBsAg-positive patients reaches 5%-15%and is even significantly higher in endemic areas.Since HBV vaccination programs were implemented,HDV prevalence has decreased among younger populations.However,owing to immigrant influx,it has increased in some Western countries.the current practice of HDV screening in HBsAg-positive individuals is stepwise,based on physician’s discretion,and limited to at-risk populations and may require numerous visits.Double reflex testing,which includes anti-HDV testing in all HBsAg-positive individuals and then HDV RNA testing for anti-HDV-positive ones,is uncommon.Reflex testing can identify more HDV infection cases and link identified patients to further care and follow-up.Moreover,laboratory-based double reflex screening is less biased than physician-led testing.therefore,health-care providers should learn about reflex testing,and federal and provincial hepatitis control programs should implement laboratory-based double reflex testing to obtain reliable HDV prevalence estimates.the test’s cost-effectiveness depends on the number of HBV-positive patients screened to identify one HDV-positive patient.Such testing may be viable in areas with low HBsAg but high HDV prevalence.However,its economic impact on areas with low HDV prevalence needs further study.

关键词： Anti-hepatitis D virus antibody HBsAg Hepatitis D virus RNA Hepatitis B Hepatitis D Reflex testing

Characteristics of settling of dilute suspension of particles with different density at high Reynolds numbers

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Particuology 2021年第3期19卷 62-74页

作者： Ali abbas Zaidi Department of Mechanical and Process Engineering ETH Zurich8092 ZurichSwitzerland

Dilute suspension of particles with same density and size develops clusters when settle at high Reynolds number(≥250).It is due to particles entrapment in the wakes produced by upstream particles.In this work,this phenomenon is studied for suspension having particles with different densities by numerical simulations.the particle-fluid interactions are modelled using immersed boundary method and inter-particle collisions are modelled using discrete element method.In simulations,settling Reynolds number is always kept above 250 and the suspension solid volume fraction is nearly 0.1 percent.two particle density ratios(i.***.density of heavy particles to lighter particles)equal to 4:1 and 2:1 and particles with same density are studied.For each density ratio,the percentage volume fraction of each particle density is nearly varied from 0.8 to 0.2.Settling characteristics such as microstructures of settling particle,average settling velocity and velocity fluctuations of settling particles are studied.Simulations show that for different density particles settling characteristics of suspension is largely dominated by heavy particles.At the end of paper,the underlying physics is explained for the anomalies observed in simulation.

关键词： Particle clustering at high reynolds number Suspension with different density particles Particle microstructure due to settling Immersed boundary method