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Numerical investigation of transitions in flow states and variation in aerodynamic forces for flow around square cylinders arranged inline

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Chinese Journal of Aeronautics 2018年第11期31卷 2111-2123页

作者： Waqas SARWAR ABBASI Shams ul ISLAM Lubna FAIZ Hamid RAHMAN Mathematics Department Air UniversityIslamabad Mathematics Department COMSATS Institute of Information Technology Mathematics and Statistics Department Bacha Khan University

This study focuses on the transitions in flow states around two-, three-and four-inline square cylinders under the effect of Reynolds numbers at two different gap spacing values using the lattice Boltzmann method. For this purpose, Reynolds number is varied in the range 1–130 while two different values of spacing taken into account are gap spacing =2 and 5. Before going to actual problem, the code is tested for flow around a single square cylinder by comparing the results with experimental and numerical results of other researchers, and good agreement is *** current numerical computations yield that for both spacing values and all combinations of cylinders there exist three different sates of flow depending on Reynolds numbers: steady state, transitional state and unsteady state. It is found that the range of Reynolds numbers for these flow states is different for both spacing values. At gap spacing =2 the range of Reynolds numbers for each flow state decreases by increasing the number of cylinders while at gap spacing =5 opposite trend is observed. The results also show that at gap spacing =2 the reduction in drag force is greater than the corresponding reduction at gap spacing =5. The maximum reduction in drag force is observed at Reynolds numbers =1 at both spacing values. Similarly, at both spacing values and all Reynolds numbers, the maximum reduction in drag force is observed for the case of four-inline square cylinders.

关键词： Drag reduction Flow states Gap spacing Inline cylinders Reynolds number

Trends in species distribution modelling in context of rare and endemic plants:a systematic review

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Ecological Processes 2022年第1期11卷 525-535页

作者： Ammad Waheed Qazi Zafeer Saqib Muhammad Zaman‑ul‑Haq Department of Environmental Science International Islamic University IslamabadIslamabad 46000Pakista

Background:Many research papers have utilized Species Distribution Models to estimate a species’current and future geographic distribution and environmental *** study aims to(a)understand critical features of SDMs used to model endemic and rare species and(b)to identify possible constraints with the collected *** present systematic review examined how SDMs are used on endemic and rare plant species to identify optimal practices for future ***:The evaluated literature(79 articles)was published between January 2010 and December *** number of papers grew considerably over *** studies were primarily conducted in Asia(41%),Europe(24%),and Africa(2%).The bulk of the research evaluated(38%)focused on theoretical ecology,climate change impacts(19%),and conservation policy and planning(22%).Most of the papers were published in publications devoted to biodiversity conservation,ecological or multidisciplinary *** degree of uncertainty was not disclosed in most studies(81%).Conclusion:This systematic review provides a broad overview of the emerging trends and gaps in the SDMs *** majority of studies failed to present uncertainties and error ***,when model performance estimates are given,the model results will be highly effective,allowing for more assurance in the predictions they ***,based on our systematic review,we recommend that in the future rare and endemic SDMs should represent uncertainty levels and estimates of errors in the modelling process.

关键词： Species distribution modelling Endemic Rare Uncertainty measures Model validation

Additive Parameter for Deep Face Recognition

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Communications in Mathematics and Statistics 2020年第2期8卷 203-217页

作者： Jamshaid ul Rahman Qing Chen Zhouwang Yang School of Mathematical Sciences University of Science and Technology of China96 Jinzhai RoadHefei 230026AnhuiPeople’s Republic of China

The performance of feature learning for deep convolutional neural networks(DCNNs)is increasing promptly with significant improvement in numerous *** studies on loss functions clearly describing that better normalization is helpful for improving the performance of face recognition(FR).Several methods based on different loss functions have been proposed for FR to obtain discriminative *** this paper,we propose an additive parameter depending on multiplicative angular margin to improve the discriminative power of feature embedding that can be easily *** additive parameter approach,an automatic adjustment of the seedling element as the result of angular marginal seed is offered in a particular way for the angular softmax to learn angularly discriminative *** train the model on publically available dataset CASIA-WebFace,and our experiments on famous benchmarks YouTube Faces(YTF)and labeled face in the wild(LFW)achieve better performance than the various state-of-the-art approaches.

关键词： Additive parameter Angular margin Deep convolutional neural networks Face recognition Softmax loss

Phytochemicals targeting NF-kB signaling:Potential anti-cancer interventions

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Journal of Pharmaceutical Analysis 2022年第3期12卷 394-405页

作者： Akansha Chauhan Asim ul Islam Hridayesh Prakash Sandhya Singh Amity Institute of Physiology&Allied Sciences Amity UniversityNoidaUttar PradeshIndia Centre for Interdisciplinary Research in Basic Sciences Jamia Millia IslamiaNew DelhiIndia Amity Institute of Virology&Immunology Amity UniversityNoidaUttar PradeshIndia

Nuclear factor kB(NF-kB)is a ubiquitous regulator of the signalome and is indispensable for various biological cell ***-kB consists of five transcription factors that execute both cytoplasmic and nuclear signaling processes in ***-kB is the only signaling molecule that governs both pro-and antiapoptotic,and pro-and anti-inflammatory *** is due to the canonical and non-canonical components of the NF-kB signaling ***,these pathways orchestrate cancer-related inflammation,hyperplasia,neoplasia,and ***-canonical NF-kB pathways are particularly involved in the chemoresistance of cancer *** view of its pivotal role in cancer progression,NF-kB represents a potentially significant therapeutic target for modifying tumor cell *** phytochemicals are known to modulate NF-kB pathways through the stabilization of its inhibitor,IkB,by inhibiting phosphorylation and ubiquitination *** natural pharmacophores are known to inhibit the nuclear translocation of NF-kB and associated pro-inflammatory responses and cell survival *** view of this and the high degree of specificity exhibited by various phytochemicals for the NF-kB component,we herein present an in-depth overview of these phytochemicals and discuss their mode of interaction with the NF-kB signaling pathways for controlling the fate of tumor cells for cancerdirected interventions.

关键词： Cancer Transcription factor Phytochemicals Inflammation Chemoprevention

Morpho-Physiological,Biochemical and Molecular Adaptation of Millets to Abiotic Stresses:A Review

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Phyton-International Journal of Experimental Botany 2021年第5期90卷 1363-1385页

作者： Seerat Saleem Naveed ul Mushtaq Wasifa Hafiz Shah Aadil Rasool Khalid Rehman Hakeem Reiaz ul Rehman Department of Bioresources School of Biological SciencesUniversity of KashmirSrinagar190006India Department of Biological Sciences Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia

Abiotic stresses such as drought,heat,cold,nutrient deficiency,excess salt and hazardous metals can hamper plantgrowth and *** agriculture of only a few major staple food crops that are sensitive and intolerant to environmental stresses has led to an agrarian *** the other hand,nutritionally rich,gluten free and stress tolerant plants like millets are neglected and *** sustain about one-third of the world’s population and show exceptional tolerance to various abiotic and biotic *** are C4 plants that are adapted to marginal and dry lands of arid and semi-arid regions,and survive low rainfall and poor *** stresses significantly affect plant growth which ultimately results in reduced crop ***,various adaptation mechanisms have evolved in millets to withstand different *** review aims at exploring various of these morphophysiological,biochemical and molecular aspects of mechanisms in *** adaptations include short life span,smallplant height and leaf area,dense root system,adjusted flowering time,increased root and decreased shoot lengths,high tillering,and leaf folding.A high accumulation of various osmoprotectants(proline,soluble sugars,proteins)improves hyperosmolarity and enhances the activity of antioxidant enzymes(e.g.,Ascorbate peroxidase,Superoxide dismutase,Catalase,Peroxidase)providing defense against oxidative ***,plants show low photosynthetic and stomatal conductance rates,and root respiration which help them to escape from water *** adaptations include the upregulation of stress-related transcriptional factors,signalling genes,ion transporters,secondary metabolite pathways,receptor kinases,phytohormone biosynthesis and antioxidative *** of genetic resources hampers improvement of ***,several identified and characterized genes for stress tolerance can be exploited for further development of millet resil

关键词： Millets adaptation abiotic stress osmoprotectants antioxidants transcriptomics

Salt Stress Threshold in Millets:Perspective on Cultivation on Marginal Lands for Biomass

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Phyton-International Journal of Experimental Botany 2021年第1期90卷 51-64页

作者： Naveed ul Mushtaq Seerat Saleem Aadil Rasool Wasifa Hafiz Shah Khalid Rehman Hakeem Reiaz ul Rehman Department of Bioresources School of Biological SciencesUniversity of KashmirSrinagar190006India Department of Biological Sciences Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia

Millets hold an immense assurance for food safety and nourishment amid ever-rising agricultural expenses and climate *** are healthful,have supplementary wellbeing profit and need remarkably fewer effort overheads for crop *** characters draw attention to millets as a plant of preference for the humankind in the course of emergent alarm about environmental *** have the prospect to provide biomass and thus bioenergy,reduced carbon emission,carbon footprint and sustainable modern *** the rate of expansion in budding countries is increasing day by day,the scarcity of energy is a big panic and there is a mounting turn in the direction and rehearsal of waste and biomass as an energy ***,at least 20%of total irrigated land has been injured by salt and 1.5 million hectares is taken away of cultivation every ***,in future,we will have a requirement of efficient crops and utilisation of marginal lands for *** is an answer to the efficient *** are subjected to various environmental pressures(high/low temperature,heavy metal,salinity,pesticides,etc.)as well as biotic stresses(virus,bacteria,fungi,etc.)and millets are not an exception to *** are categorised as glycophytes and can tolerate average salt threshold of about 6(ECe)(dS/m)with some variation from specie to *** in the salt concentrations can lead to retarded growth and development,thus need for mitigants arise to reduce such *** mitigants to overcome the stress levels include proline,polyamine and betaines,Na2SeO3,H2S,KNO3,Mg(NO3)2,etc.

关键词： Sustainable development proline salt tolerance biomass food security

Synthesis and Crystal Structure of 2-(4-Oxo-3-o- tolyl-3,4-dihydroquinazolin-2-ylthio)acetohydrazide

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Chinese Journal of Structural Chemistry 2012年第9期31卷 1329-1333页

作者： Aamer Saeed Shams-ul-Mahmood ulrich Flörke Department of Chemistry Quaid-I-Azam UniversityIslamabad 45320Pakistan Department Chemie Fakultät fur NaturwissenschaftenUniversität PaderbornWarburgerstrasse 100D-33098 PaderbornGermany

The title compound was synthesized from 3-（2-methylphenyl）-2-thioxo-2,3-dihy- droquinazolin-4（1H）-one （4） which was prepared from 2-methylaniline in two steps. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes in the orthorhombic space group Pbca with unit cell dimensions a = 6.687（4）, b = 24.788（16）, c = 30.453（19）  V = 5048（5） 3 and Z = 8.

关键词： quinazolinone acetohydrazide synthesis

A Linearized Branch Flow Model Considering Line Shunts for Radial Distribution Systems and Its Application in Volt/VAr Control

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1191-1200页

作者： Hanyang Lin Firdous ul Nazir Bikash C.Pal Ye Guo Tsinghua-Berkeley Shenzhen Institute Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518071China Department of Electrical and Electronic Engineering Glasgow Caledonian UniversityGlasgow Caledonian UniversityGlasgowG4 OBAU.K. Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72AZU.K.

When urban distribution systems are gradually modernized,the overhead lines are replaced by underground cables,whose shunt admittances can not be *** power flow(PF)model withπequivalent circuit shows non-convexity and long computing time,and most recently proposed linear PF models assume zero shunt *** of them are not suitable for fast calculation and optimization problems of modern distribution systems with non-negligible line ***,this paper proposes a linearized branch flow model considering line shunt(LBFS).The strength of LBFS lies in maintaining the linear structure and the convex nature after appropriately modeling theπequivalent circuit for network equipment like *** results show that the calculation accuracy in nodal voltage and branch current magnitudes is improved by considering shunt *** show the application scope of LBFS by controlling the network voltages through a two-stage stochastic Volt/VAr control(VVC)problem with the uncertain active power output from renewable energy sources(RESs).Since LBFS results in a linear VVC program,the global solution is *** study exhibits that VVC framework can optimally dispatch the discrete control devices,*** transformers and shunt capacitors,and also optimize the decision rules for real-time reactive power control of ***,the computing efficiency is significantly improved compared with that of traditional VVC methods.

关键词： Line shunt linear power flow model stochastic optimization Volt/VAr control(VVC)

Structural,electronic,and magnetic properties of Co-doped ZnO

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Chinese Physics B 2012年第9期21卷 414-421页

作者： Bakhtiar ul Haq A. Afaq R. Ahmed S. Naseem Center of Excellence in Solid State Physics University of the Punjab Quid-e-Azam CampusLahore-54590 Pakistan Department of Physics Faculty of Science Universiti Teknologi Malaysia Skudai Johar Malaysia Center of Excellence in Solid State Physics University of the Punjab Quid-e-Azam Campus Lahore-54590 Pakistan

Density functional theory based calculations have been carried out to study structural, electronic, and magnetic properties of Znl-xCoxO （x = 0, 0.25, 0.50, 0.75） in the zinc-blende phase, and the generalized gradient approximation proposed by Wu and Cohen has been used. Our calculated lattice constants decrease while the bulk moduli increase with the increase of Co2＋ concentration. The calculated spin polarized band structures show the metallic behavior of Co-doped ZnO for both the up and the down spin cases with various doping concentrations. Moreover, the electron population is found to shift from the Zn-O bond to the Co-O bond with the increase of Co2~ concentration. The total magnetic moment~ the interstitial magnetic moment, the valence and the conduction band edge spin splitting energies, and the exchange constants decrease, while the local magnetic moments of Zn, Co, O, the exchange spin splitting energies, and crystal field splitting energies increase with the increase of dopant concentration.

关键词： density functional theory magnetic semiconductors generalized gradient approximation