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Financial Innovation 2020年第1期6卷 757-774页

作者： imran yousaf Shoaib Ali Air University School of Management Air UniversityIslamabadPakistan

Through the application of the VAR-AGARCH model to intra-day data for three cryptocurrencies(Bitcoin,Ethereum,and Litecoin),this study examines the return and volatility spillover between these cryptocurrencies during the pre-COVID-19 period and the COVID-19 *** also estimate the optimal weights,hedge ratios,and hedging effectiveness during both sample *** find that the return spillovers vary across the two periods for the Bitcoin–Ethereum,Bitcoin–Litecoin,and Ethereum–Litecoin ***,the volatility transmissions are found to be different during the two sample periods for the Bitcoin–Ethereum and Bitcoin–Litecoin *** constant conditional correlations between all pairs of cryptocurrencies are observed to be higher during the COVID-19 period compared to the pre-COVID-19 *** on optimal weights,investors are advised to decrease their investments(a)in Bitcoin for the portfolios of Bitcoin/Ethereum and Bitcoin/Litecoin and(b)in Ethereum for the portfolios of Ethereum/Litecoin during the COVID-19 *** hedge ratios are found to be higher during the COVID-19 period,implying a higher hedging cost compared to the pre-COVID-19 ***,the hedging effectiveness is higher during the COVID-19 period compared to the pre-COVID-19 ***,these findings provide useful information to portfolio managers and policymakers regarding portfolio diversification,hedging,forecasting,and risk management.

关键词： Return spillover Volatility spillover Cryptocurrencies Optimal weights Hedge ratios Hedging effectiveness COVID-19

Effect of family control on corporate dividend policy of firms in Pakistan

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Financial Innovation 2019年第1期5卷 711-723页

作者： imran yousaf Shoaib Ali Arshad Hassan Faculty Member Air University School of ManagementAir UniversityIslamabadPakistan Professor/Dean of Management and Social Sciences Department Capital University of Science and TechnologyIslamabadPakistan

This study examines the impact of family control on the dividend policy of firms in Pakistan,covering the period from 2009 to *** also investigates whether family control moderates the impact of firm-specific factors on the dividend *** GMM model for panel data estimation is *** mean difference univariate analysis shows that family firms differ from nonfamily firms based on financial *** multivariate analysis shows that family firms pay lower dividends than nonfamily ***,firm size inversely affects the dividend policy,whereas tangibility positively affects ***,family control does not moderate the impact of all firm-specific factors on the dividend ***,family control,size,and tangibility are found to be the main determinants of the dividend policy in Pakistan.

关键词： Family firm Family ownership Dividend,Minority shareholder Expropriation Agency conflicts

Herding behavior in Ramadan and financial crises: the case of the Pakistani stock market

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Financial Innovation 2018年第1期4卷 242-255页

作者： imran yousaf Shoaib Ali Syed Zulfiqar Ali Shah Management Sciences Capital University of Science and TechnologyIslamabadPakistan Air University School of Management Air UniversityIslamabadPakistan International Islamic University IslamabadPakistan.

This study examines herding behavior in the Pakistani Stock Market under different market conditions,focusing on the Ramadan effect and Crisis period by using data from 2004 to *** regression models of Christie and Huang(Financ Analysts J 51:31-37,1995)and Chang et al.,(J Bank Finance 24:1651-1679,2000)are used for herding *** based on daily stock data reveal that there is an absence of herding behavior during rising(up)and falling(down)market as well as during high and low volatility in *** herding behavior is detected during low trading volume *** analysis shows that herding existed during 2005,2006 and 2007,while it is not evident during rest of the ***,herding behavior is not detected during ***,during financial crisis of 2007-08,Pakistani Stock Market exhibits herding behavior due to higher uncertainty and information asymmetry.

关键词： Herding behavior Financial crisis Ramadan effect Stock markets

Store of value or speculative investment?Market reaction to corporate announcements of cryptocurrency acquisition

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Financial Innovation 2023年第1期9卷 3106-3136页

作者： AndréD.Gimenes Jéfferson A.Colombo imran yousaf Banco Bradesco SA(NYSE:BBD B3:BBDC3)Cidade de DeusS/no Vila YaraOsascoSP 06029‑900Brazil São Paulo School of Economics Getulio Vargas Foundation(FGVEESPBrazil)474 Itapeva St.‑Bela VistaSão PauloSP 01332‑000Brazil College of Business and Public Management Wenzhou-Kean UniversityWenzhouChina Adnan Kassar School of Business Lebanese American UniversityBeirutLebanon

In this study,we analyze the stock market reaction to 35 events associated with 32 publicly traded companies from six countries that have announced cryptocurrency acquisitions,selling,or acceptance as a means of *** analysis focuses on traditional firms whose core business is unrelated to blockchain or *** find that the aggregate market reaction around these events is slightly positive but statistically insignificant for most event ***,when we perform heterogeneity analyses,we observe significant differences in market reaction between events with high(larger CARs)and low cryptocurrency exposure(lower CARs).Multivariate regressions show that the level of exposure to cryptocurrency("skin in the game")is a critical factor underlying abnormal returns around the *** analyses reveal that economically meaningful acquisitions of BTC or ETH(relative to firm’s total assets)drive the observed *** findings have important implications for managers,investors,and analysts as they shed light on the relationship between cryptocurrency adoption and firm value.

关键词： Corporate cryptocurrency acquisition Bitcoin Cryptocurrency Blockchain Market reaction

Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.imran T.ASGHAR Z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

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Ensembling Neural Networks for User’s Indoor Localization Using Magnetic Field Data from Smartphones

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Computers, Materials & Continua 2021年第8期68卷 2597-2620页

作者： imran Ashraf Soojung Hur yousaf Bin Zikria Yongwan Park Department of Information and Communication Engineering Yeungnam UniversityGyeongsan-si38541Korea

Predominantly the localization accuracy of the magnetic field-based localization approaches is severed by two limiting factors:Smartphone heterogeneity and smaller data *** use of multifarioussmartphones cripples the performance of such approaches owing to the variability of the magnetic field *** the same vein,smaller lengths of magnetic field data decrease the localization accuracy *** current study proposes the use of multiple neural networks like deep neural network(DNN),long short term memory network(LSTM),and gated recurrent unit network(GRN)to perform indoor localization based on the embedded magnetic sensor of the smartphone.A voting scheme is introduced that takes predictions from neural networks into consideration to estimate the current location of the *** to conventional magnetic field-based localization approaches that rely on the magnetic field data intensity,this study utilizes the normalized magnetic field data for this *** of neural networks is carried out using Galaxy S8 data while the testing is performed with three devices,i.e.,LG G7,Galaxy S8,and LG *** are performed during different times of the day to analyze the impact of time *** indicate that the proposed approach minimizes the impact of smartphone variability and elevates the localization *** comparison with three approaches reveals that the proposed approach outperforms them in mean,50%,and 75%error even using a lesser amount of magnetic field data than those of other approaches.

关键词： Indoor localization magnetic field data long short term memory network data normalization gated recurrent unit network deep learning

Prediction Models for COVID-19 Integrating Age Groups, Gender, and Underlying Conditions

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Computers, Materials & Continua 2021年第6期67卷 3009-3044页

作者： imran Ashraf Waleed SAlnumay Rashid Ali Soojung Hur Ali Kashif Bashir yousaf Bin Zikria Department of Information and Communication Engineering Yeungnam UniversityGyeongsan-si38541Korea Department of Computer Science King Saud UniversityRiyadhSaudi Arabia School of Intelligent Mechatronics Engineering Sejong UniversityKorea Department of Computing and Mathematics Manchester Metropolitan UniversityManchesterUnited Kingdom

The COVID-19 pandemic has caused hundreds of thousands of deaths,millions of infections worldwide,and the loss of trillions of dollars for many large *** poses a grave threat to the human population with an excessive number of patients constituting an unprecedented challenge with which health systems have to *** from many domains have devised diverse approaches for the timely diagnosis of COVID-19 to facilitate medical *** the same vein,a wide variety of research studies have investigated underlying medical conditions for indicators suggesting the severity and mortality of,and role of age groups and gender on,the probability of COVID-19 *** study aimed to review,analyze,and critically appraise published works that report on various factors to explain their relationship with *** studies span a wide range,including descriptive analyses,ratio analyses,cohort,prospective and retrospective *** studies that describe indicators to determine the probability of infection among the general population,as well as the risk factors associated with severe illness and mortality,are critically analyzed and these ndings are discussed in detail.A comprehensive analysis was conducted on research studies that investigated the perceived differences in vulnerability of different age groups and genders to severe outcomes of *** incorporating important demographic,health,and socioeconomic characteristics are highlighted to emphasize their ***,the lack of an appropriated dataset that contains demographic,personal health,and socioeconomic information implicates the efcacy and efciency of the discussed *** are overstated on the part of both exclusion of quarantined and patients with mild symptoms and inclusion of the data from hospitals where the majority of the cases are potentially ill.

关键词： COVID-19 age&gender vulnerability for COVID-19 machine learning-based prognosis COVID-19 vulnerability psychological factors prediction of COVID-19

Novel LaFe_(2)O_(4)spinel structure with a large oxygen reduction response towards protonic ceramic fuel cell cathode

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Journal of Rare Earths 2023年第3期41卷 413-421,I0004页

作者： Jinping Wang Yuzheng Lu Naveed Mushtaq M.A.K yousaf Shah Sajid Rauf Peter D.Lund Muhammad imran Asghar School of Energy and Power Engineering Nanjing Institute of TechnologyNanjing 211167China School of Electronic Engineering Nanjing Xiao Zhuang UniversityNanjing 211171China Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology/Energy Storage Joint Research Center School of Energy and EnvironmentSoutheast UniversityNanjing 210096China College of Electronics and Information Engineering Shenzhen UniversityShenzhen 518000China New Energy Technologies Group Department of Applied PhysicsAalto University School of ScienceP.O.Box.15100FI00076AaltoEspooFinland Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Faculty of Physics and Electronic ScienceHubei UniversityWuhan 430062China

Highly active and stable electrocatalysts are mandatory for developing high-performance and longlasting fuel *** current study demonstrates a high oxygen reduction reaction(ORR)electrocatalytic activity of a novel spinel-structured LaFe_(2)O_(4)via a self-doping *** LaFe_(2)O_(4)demonstrates excellent ORR activity in a protonic ceramic fuel cell(PCFC)at temperature range of 350-500℃.The high ORR activity of LaFe_(2)O_(4)is mainly attributed to the facile release of oxide and proton ions,and improved synergistic incorporation abilities associated with interplay of multivalent Fe^(3+)/Fe^(2+)and La^(3+)*** LaFe_(2)O_(4)as cathode over proton conducting BaZr_(0.4)Ce_(0.4)Y_(0.2)O_(3)(BZCY)electrolyte,the fuel cell has delivered a high-power density of 806 mW/cm^(2)operating at 500℃.Different spectroscopic and calculations methods such as UV-visible,Raman,X-ray photoelectron spectroscopy and density functional theory(DFT)calculations were performed to screen the potential application of LaFe_(2)O_(4)as *** study would help in developing functional cobalt-free ORR electrocatalysts for low temperature-PCFCs(LT-PCFCs)and solid oxide fuel cells(SOFCs)applications.

关键词： LaFe_(2)O_(4)cathode Facile Fe^(3+/2+)ions resale Oxygen reductionreaction(ORR) Excellent electrocatalyst Protonic ceramicfuel cell(PCFC) Rare earths

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On the Metric Dimension of Barycentric Subdivision of Cayley Graphs

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Acta Mathematicae Applicatae Sinica 2016年第4期32卷 1067-1072页

作者： Muhammad imran Department of Mathematics School of Natural Sciences National University of Sciences and Technology Sector H-12 Islamabad Pakistan

In a connected graph G, the distance d（u, v） denotes the distance between two vertices u and v of G. Let W = {w1, w2,……, wk} be an ordered set of vertices of G and let v be a vertex of G. The representation r（v1W） of v with respect to W is the k-tuple （d（v, w1）, d（v, w2）,…, d（v, wk））. The set W is called a resolving set or a locating set if every vertex of G is uniquely identified by its distances from the vertices of W, or equivalently, if distinct vertices of G have distinct representations with respect to W. A resolving set of minimum cardinality is called a metric basis for G and this cardinality is the metric dimension of G, denoted by β（G）. Metric dimension is a generalization of affine dimension to arbitrary metric spaces （provided a resolving set exists）. In this paper, we study the metric dimension of barycentric subdivision of Cayley graphs Cay （Zn Z2）. We prove that these subdivisions of Cayley graphs have constant metric dimension and only three vertices chosen appropriately suffice to resolve all the vertices of barycentric subdivision of Cayley graphs Cay （Zn Z2）.

关键词： metric dimension basis resolving set barycentric subdivision Cayley graph

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Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： Arshad ASHRAF imran AHMAD Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

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