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A Hybrid SIR-Fuzzy Model for Epidemic Dynamics:A Numerical Study

Computer Modeling in Engineering & Sciences 2024年第6期139卷 3417-3434页

作者： Muhammad shoaib Arif Kamaleldin Abodayeh Yasir Nawaz Department of Mathematics and Sciences College of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Mathematics Air UniversityIslamabad44000Pakistan

This study focuses on the urgent requirement for improved accuracy in diseasemodeling by introducing a newcomputational framework called the Hybrid SIR-Fuzzy Model.By integrating the traditional Susceptible-Infectious-Recovered(SIR)modelwith fuzzy logic,ourmethod effectively addresses the complex nature of epidemic dynamics by accurately accounting for uncertainties and imprecisions in both data and model parameters.The main aim of this research is to provide a model for disease transmission using fuzzy theory,which can successfully address uncertainty in mathematical modeling.Our main emphasis is on the imprecise transmission rate parameter,utilizing a three-part description of its membership level.This enhances the representation of disease processes with greater complexity and tackles the difficulties related to quantifying uncertainty in mathematical models.We investigate equilibrium points for three separate scenarios and perform a comprehensive sensitivity analysis,providing insight into the complex correlation betweenmodel parameters and epidemic results.In order to facilitate a quantitative analysis of the fuzzy model,we propose the implementation of a resilient numerical scheme.The convergence study of the scheme demonstrates its trustworthiness,providing a conditionally positive solution,which represents a significant improvement compared to current forward Euler schemes.The numerical findings demonstrate themodel’s effectiveness in accurately representing the dynamics of disease transmission.Significantly,when the mortality coefficient rises,both the susceptible and infected populations decrease,highlighting the model’s sensitivity to important epidemiological factors.Moreover,there is a direct relationship between higher Holling type rate values and a decrease in the number of individuals who are infected,as well as an increase in the number of susceptible individuals.This correlation offers a significant understanding of how many elements affect the consequences of an epidemic.Our objective is to enh

关键词： Fuzzy-based model sensitivity equilibriumpoints proposed numerical scheme convergence and stability analysis

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Construction of a Computational Scheme for the Fuzzy HIV/AIDS Epidemic Model with a Nonlinear Saturated Incidence Rate

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1405-1425页

This work aimed to construct an epidemic model with fuzzy parameters.Since the classical epidemic model doesnot elaborate on the successful interaction of susceptible and infective people,the constructed fuzzy epidemicmodel discusses the more detailed versions of the interactions between infective and susceptible people.Thenext-generation matrix approach is employed to find the reproduction number of a deterministic model.Thesensitivity analysis and local stability analysis of the systemare also provided.For solving the fuzzy epidemic model,a numerical scheme is constructed which consists of three time levels.The numerical scheme has an advantage overthe existing forward Euler scheme for determining the conditions of getting the positive solution.The establishedscheme also has an advantage over existing non-standard finite difference methods in terms of order of accuracy.The stability of the scheme for the considered fuzzy model is also provided.From the plotted results,it can beobserved that susceptible people decay by rising interaction parameters.

关键词： Epidemic model fuzzy rate parameters next generation matrix local stability proposed numerical scheme

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Multi-Elemental Chemostratigraphy,Sequence Development,Depositional History,and Environmental Importance of Early Eocene Red Beds(Kuldana Formation)in NW Himalayas,Pakistan

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Journal of Earth Science 2024年第2期35卷 349-375页

作者： Amir Shahzad George Kontakiotis Thierry Adatte Khawaja shoaib Ahmed Muhammad Tayyib Riaz Hammad Tariq Janjuhah Evangelia Besiou Institute of Geology University of Azad Jammu and KashmirMuzaffarabad13100Pakistan Department of Historical Geology-Paleontology Faculty of Geology and GeoenvironmentSchool of Earth SciencesNational and Kapodistrian University of AthensPanepistimiopolisZografou15784Greece Institute of Earth Sciences(ISTE) University of LausanneLausanneCH-1015Switzerland Department of Geology Shaheed Benazir Bhutto UniversitySheringalPeshawar18050Pakistan

The Eocene Kuldana Formation(KF)in the Yadgar area of Pakistan,comprises a diverse range of sedimentary facies,including variegated red beds of shales,mudstones,and sandstones,as well as interbedded limestone and marl.In this study,we conducted an integrated micropaleontological,sedimentological,mineralogical,and geochemical investigation to determine the depositional setting,biochronology,provenance,and paleoclimate of the KF.The study identified six lithofacies and six microfacies,which indicate a variety of environments ranging from floodplains and channels to the margins and shallow marine settings.The nannofossil biostratigraphy places the KF in the Early Eocene,more precisely the NP10 zone(Ypresian),and the fossil zone of benthic foraminifera classifies the study section as the Shallow Benthic Zone SBZ-8(Middle Ilerdian 2).In terms of petrography,the KF sandstone was classified as litharenite and feldspathic litharenite,while the QtFL diagram suggests a recycled orogen.Geochemical proxies indicate an oxidizing environment,a high-to-low regular sedimentation rate,moderate-to-intense chemical weathering in the source region,and a warm-humid to dry climate during the deposition of KF.Overall,the findings suggest that the deposition of KF marks the end of Neo-Tethys due to the Early Eocene Indian–Kohistan collision and that the uplifting of the Himalayas provided the source for the deposition of KF in the foreland basin.The study provides new insights into the depositional environment,biochronology,provenance,and paleoclimate of KF,and highlights the potential for red beds as reliable indicators of oxygenation levels in proximity to mineral deposits.

关键词： sedimentary microfacies Paleocene–Eocene thermal maximum stratigraphic correlations paleoenvironmental reconstruction nannofossils paleontology

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Discovering interlinkages between major cryptocurrencies using high‑frequency data: new evidence from COVID‑19 pandemic

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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 period.We also estimate the optimal weights,hedge ratios,and hedging effectiveness during both sample periods.We find that the return spillovers vary across the two periods for the Bitcoin–Ethereum,Bitcoin–Litecoin,and Ethereum–Litecoin pairs.However,the volatility transmissions are found to be different during the two sample periods for the Bitcoin–Ethereum and Bitcoin–Litecoin pairs.The constant conditional correlations between all pairs of cryptocurrencies are observed to be higher during the COVID-19 period compared to the pre-COVID-19 period.Based 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 period.All hedge ratios are found to be higher during the COVID-19 period,implying a higher hedging cost compared to the pre-COVID-19 period.Last,the hedging effectiveness is higher during the COVID-19 period compared to the pre-COVID-19 period.Overall,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

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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 2014.Two 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 estimations.Results 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 market.While herding behavior is detected during low trading volume days.Yearly analysis shows that herding existed during 2005,2006 and 2007,while it is not evident during rest of the period.However,herding behavior is not detected during Ramadan.Furthermore,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

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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 2016.It also investigates whether family control moderates the impact of firm-specific factors on the dividend policy.The GMM model for panel data estimation is used.The mean difference univariate analysis shows that family firms differ from nonfamily firms based on financial characteristics.The multivariate analysis shows that family firms pay lower dividends than nonfamily firms.Besides,firm size inversely affects the dividend policy,whereas tangibility positively affects it.Moreover,family control does not moderate the impact of all firm-specific factors on the dividend policy.Overall,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

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National guidelines for the diagnosis and treatment of hilar cholangiocarcinoma

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World Journal of Gastroenterology 2024年第9期30卷 1018-1042页

作者： Faisal Saud Dar Zaigham Abbas Irfan Ahmed Muhammad Atique Usman Iqbal Aujla Muhammad Azeemuddin Zeba Aziz Abu Bakar Hafeez Bhatti Tariq ali Bangash Amna Subhan Butt Osama Tariq Butt Abdul Wahab Dogar Javed Iqbal Farooqi Faisal Hanif Jahanzaib Haider Siraj Haider Syed Mujahid Hassan Adnan Abdul Jabbar Aman Nawaz Khan Muhammad shoaib Khan Muhammad Yasir Khan Amer Latif Nasir Hassan Luck Ahmad Karim Malik Kamran Rashid Sohail Rashid Mohammad Salih Abdullah Saeed Amjad Salamat Ghias-un-Nabi Tayyab Aasim Yusuf Haseeb Haider Zia Ammara Naveed Department of Hepatopancreatic Biliary Surgery&Liver Transplant Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Hepatogastroenterology and Liver Transplantation Dr.Ziauddin University HospitalKarachi 75600SindhPakistan University of Aberdeen Aberdeen B243FXUnited Kingdom Department of Pathology Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Gastroenterology&Hepatology Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Radiology Aga Khan UniversityKarachi 74800Pakistan Department of Oncology Hameed Latif HospitalLahore 54000Pakistan Division of Hepatopancreatic Biliary Surgery&Liver Transplantation Shifa International HospitalIslamabad 44000Pakistan Department of Hepatopancreatic Biliary Surgery&Liver Transplant Shaikh Zayed Hospital and Post Graduate Medical InstituteLahore 54000Pakistan Department of Medicine Aga Khan University HospitalKarachi 74800Pakistan Department of Liver Transplant Pir Abdul Qadir Shah Jeelani Institute of Medical SciencesGambat 66020Pakistan Department of Medicine&Gastroenterology Lifecare Hospital and Research CentrePeshawar 25000Khyber PakhtunkhwaPakistan Department of Hepatopancreatobiliary&Liver Transplant Bahria International HospitalLahore 54000Pakistan Department of Surgery Hepatopancreatobiliary&Liver TransplantDow University of Health SciencesKarachi 74800Pakistan Department of Gastroenterology Hepatology&NutritionPir Abdul Qadir Shah Jeelani Institute of Medical SciencesGambat 66020Pakistan Department of Oncology Dr.Ziauddin HospitalKarachi 74800Pakistan Department of Radiology Rehman Medical InstitutePeshawar 25000Pakistan Army Liver Transplant Unit Pak Emirates Military HospitalRawalpindi 46000Pakistan Department of Gastroenterology Sindh Institute of Urology and TransplantationKarachi 75500Pakistan Rashid Nursing Home and Cancer Clinic Rashid Nursing Home and Cancer ClinicRawalpindi 46000Pakistan Department of Gastroentero

A consensus meeting of national experts from all major national hepatobiliary centres in the country was held on May 26,2023,at the Pakistan Kidney and Liver Institute&Research Centre(PKLI&RC)after initial consultations with the experts.The Pakistan Society for the Study of Liver Diseases(PSSLD)and PKLI&RC jointly organised this meeting.This effort was based on a comprehensive literature review to establish national practice guidelines for hilar cholangiocarcinoma(hCCA).The consensus was that hCCA is a complex disease and requires a multidisciplinary team approach to best manage these patients.This coordinated effort can minimise delays and give patients a chance for curative treatment and effective palliation.The diagnostic and staging workup includes high-quality computed tomography,magnetic resonance imaging,and magnetic resonance cholangiopancreato-graphy.Brush cytology or biopsy utilizing endoscopic retrograde cholangiopancreatography is a mainstay for diagnosis.However,histopathologic confirmation is not always required before resection.Endoscopic ultrasound with fine needle aspiration of regional lymph nodes and positron emission tomography scan are valuable adjuncts for staging.The only curative treatment is the surgical resection of the biliary tree based on the Bismuth-Corlette classification.Selected patients with unresectable hCCA can be considered for liver transplantation.Adjuvant chemotherapy should be offered to patients with a high risk of recurrence.The use of preoperative biliary drainage and the need for portal vein embolisation should be based on local multidisciplinary discussions.Patients with acute cholangitis can be drained with endoscopic or percutaneous biliary drainage.Palliative chemotherapy with cisplatin and gemcitabine has shown improved survival in patients with irresectable and recurrent hCCA.

关键词： Hilar cholangiocarcinoma Bismuth-Corlette classification Memorial Sloan Kettering Cancer Centre Staging Preoperative biliary drainage Portal vein embolisation Surgical resection Hepatectomy

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General Classes of Variance Estimators in Simple Random Sampling Using Multi-auxiliary Variables

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Journal of Mathematics and System Science 2013年第5期3卷 262-269页

作者： Zahoor Ahmad shoaib ali Muhammad Hanif Department of Statistics University of Gujrat Crujrat 50700 Pakisan National College of Business Administration and Economic Lahore 54000 Pakistan

Srivastava and Jhajj [16] proposed a class of estimators for estimating population variance using multi auxiliary variables in simple random sampling and they utilized the means and variances of auxiliary variables. In this paper, we adapted this class and motivated by Searle [13], and we suggested more generalized class of estimators for estimating the population variance in simple random sampling. The expressions for the mean square error of proposed class have been derived in general form. Besides obtaining the minimized MSE of the proposed and adapted class, it is shown that the adapted classis the special case of the proposed class. Moreover, these theoretical findings are supported by an empirical study of original data.

关键词：简单随机抽样方差估计辅助变量最小均方误差通用总体方差一般形式原始数据

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AMC Integrated Multilayer Wearable Antenna for Multiband WBAN Applications

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Computers, Materials & Continua 2022年第5期71卷 3227-3241页

作者： Iqra Aitbar Nosherwan shoaib Akram Alomainy Abdul Quddious Symeon Nikolaou Muhammad ali Imran Qammer H.Abbasi Research Institute for Microwave and Millimeter-Wave Studies(RIMMS)National University of Sciences and Technology(NUST) H-1244000IslamabadPakistan School of Electronic Engineering and Computer Science Queen Mary University of LondonLondonE14NSUK KIOS Research and Innovation Center of Excellence University of Cyprus2109NicosiaCyprus Frederick Research Center(FRC)and Department of Electrical Engineering Frederick University1036NicosiaCyprus James Watt School of Engineering University of GlasgowGlasgowG128QQU.K

In this paper,a compact,efficient and easy to fabricate wearable antenna integrated with Artificial Magnetic Conductor(AMC)is presented.Addition of slots and bevels/cuts in the rectangular monopole patch antenna yield a wide bandwidth along with band notches.The proposed antenna is backed with an AMC metasurface that changes the bidirectional radiation pattern to a unidirectional,thus,considerably reducing the Specific Absorption Ratio(SAR).The demonstrated antenna has a good coverage radiating away from the body and presents reduced radiation towards the body with a front-to-back ratio of 13 dB and maximum gain of 3.54 dB.The proposed design operates over a wide frequency band of 2.9 to 12 GHz(exceeding the designated 3.1−10.6 GHz Ultra-Wideband(UWB)band).The band notches were created using slots on the radiating patch in the sub-bands from 5.50 to 5.67 GHz and 7.16 to 7.74 GHz.The overall dimensions of the structure are 33×33×6.75 mm3.The antenna’s radiation performance increased considerably with the addition of the AMC layer.The SAR values for the antenna are reduced by 85.3%when the AMC is used and are 0.083 W/kg which is well below the FCC SAR limits.The simple design,miniaturized profile,low SAR and wide operating bands with multiple band notches make the presented antenna an appealing choice for several UWB wearable body area network(WBAN)applications.

关键词： Ultra-wideband(UWB) monopole antenna wearable antenna specific absorption ratio(SAR)

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Trustworthy Explainable Recommendation Framework for Relevancy

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Computers, Materials & Continua 2022年第12期73卷 5887-5909页

作者： Saba Sana Mohammad shoaib Department of Computer Science University of Engineering and TechnologyLahore54000Pakistan

Explainable recommendation systems deal with the problem of‘Why’.Besides providing the user with the recommendation,it is also explained why such an object is being recommended.It helps to improve trustworthiness,effectiveness,efficiency,persuasiveness,and user satisfaction towards the system.To recommend the relevant information with an explanation to the user is required.Existing systems provide the top-k recommendation options to the user based on ratings and reviews about the required object but unable to explain the matched-attribute-based recommendation to the user.A framework is proposed to fetch the most specific information that matches the user requirements based on Formal Concept Analysis(FCA).The ranking quality of the recommendation list for the proposed system is evaluated quantitatively with Normalized Discounted Cumulative Gain(NDCG)@k,which is better than the existing systems.Explanation is provided qualitatively by considering trustworthiness criterion i.e.,among the seven explainability evaluation criteria,and its metric satisfies the results of proposed method.This framework can be enhanced to accommodate for more effectiveness and trustworthiness.

关键词： Explainable recommendation data analysis formal concept analysis(FCA)approach

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