Mathematics, Statistics & Physics: Recent submissions

Now showing items 441-460 of 781

    • Investigation of NH3 adsorption on noble metal modified MoSe2 

      Ahmad I., Ayesh ( Elsevier , 2022 , Article)
      Gas pollutants represent hazard for the quality of the ambient environment, thus, the development of sensitive and selective gas sensors is essential to monitor and maintain its decent quality. The adsorption of NH3 gas ...

    • Characterizing the effective reproduction number during the COVID-19 pandemic: Insights from Qatar’s experience 

      Bsat, Raghid; Chemaitelly, Hiam; Coyle, Peter; Tang, Patrick; Hasan, Mohammad R; ... more authors ( International Society of Global Health , 2022 , Article)
      Background: The effective reproduction number, Rt, is a tool to track and understand epidemic dynamics. This investigation of Rt estimations was conducted to guide the national COVID-19 response in Qatar, from the onset ...

    • Goodness-of-fit testing based on Gini Index of spacings for progressively Type-II censored data 

      Pakyari, Reza ( Taylor & Francis , 2021 , Article)
      In this article, we propose two new scale invariant test statistics when the available data are subject to progressively Type-II censoring. The proposed tests are based on Gini index of spacings. It is observed thorough ...

    • On goodness-of-fit testing for Burr type X distribution under progressively type-II censoring 

      Pakyari, Reza; Baklizi, Ayman ( Springer , 2022 , Article)
      In this article, we propose two goodness-of-fit test statistics for the Burr Type X distribution when the available data are subject to progressively Type-II censoring. The proposed test statistics are based on the sample ...

    • Relative infectiousness of SARS-CoV-2 vaccine breakthrough infections, reinfections, and primary infections. 

      Abu-Raddad, Laith J; Chemaitelly, Hiam; Ayoub, Houssein H; Tang, Patrick; Coyle, Peter; ... more authors ( Springer , 2022 , Article)
      SARS-CoV-2 breakthrough infections in vaccinated individuals and in those who had a prior infection have been observed globally, but the transmission potential of these infections is unknown. The RT-qPCR cycle threshold ...

    • A novel method to generate key-dependent s-boxes with identical algebraic properties 

      Ahmad Y., Al-Dweik; Hussain, Iqtadar; Saleh, Moutaz; Mustafa, M.T. ( Elsevier , 2022 , Article)
      The s-box plays the vital role of creating confusion between the ciphertext and secret key in any cryptosystem, and is the only nonlinear component in many block ciphers. Dynamic s-boxes, as compared to static, improve ...

    • Detection of DNA Bases via Field Effect Transistor of Graphene Nanoribbon with a Nanopore: Semi-empirical Modeling 

      Wasfi, Asma; Awwad, Falah; Ayesh, Ahmad I. ( Institute of Electrical and Electronics Engineers , 2021 , Article)
      DNA sequencing techniques are critical in order to investigate genes’ functions. Obtaining fast, accurate, and affordable DNA bases detection makes it possible to acquire personalized medicine. In this article, a ...

    • Association of Prior SARS-CoV-2 Infection With Risk of Breakthrough Infection Following mRNA Vaccination in Qatar. 

      Abu-Raddad, Laith J; Chemaitelly, Hiam; Ayoub, Houssein H; Yassine, Hadi M; Benslimane, Fatiha M; ... more authors ( American Medical Association , 2021 , Article)
      The effect of prior SARS-CoV-2 infection on vaccine protection remains poorly understood. To assess protection from SARS-CoV-2 breakthrough infection after mRNA vaccination among persons with vs without prior SARS-CoV-2 ...

    • BNT162b2 and mRNA-1273 COVID-19 vaccine effectiveness against the SARS-CoV-2 Delta variant in Qatar. 

      Tang, Patrick; Hasan, Mohammad R; Chemaitelly, Hiam; Yassine, Hadi M; Benslimane, Fatiha M; ... more authors ( Nature Researc , 2021 , Article)
      With the global expansion of the highly transmissible SARS-CoV-2 Delta (B.1.617.2) variant, we conducted a matched test-negative case-control study to assess the real-world effectiveness of COVID-19 messenger RNA vaccines ...

    • Epidemiological impact of prioritising SARS-CoV-2 vaccination by antibody status: Mathematical modelling analyses 

      Ayoub, H.H.; Ayoub, Houssein H.; Chemaitelly, Hiam; Makhoul, Monia; Al Kanaani, Zaina; ... more authors ( BMJ Publishing Group , 2021 , Article)
      Background Vaccines against SARS-CoV-2 have been developed, but their availability falls far short of global needs. This study aimed to investigate the impact of prioritising available doses on the basis of recipient ...

    • SARS-CoV-2 antibody-positivity protects against reinfection for at least seven months with 95% efficacy 

      Laith J., Abu-Raddad; Chemaitelly, Hiam; Coyle, Peter; Malek, Joel A.; Ahmed, Ayeda A.; ... more authors ( Elsevier , 2021 , Article)
      Background Reinfection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been documented, raising public health concerns. SARS-CoV-2 reinfections were assessed in a cohort of antibody-positive persons ...

    • mRNA-1273 COVID-19 vaccine effectiveness against the B.1.1.7 and B.1.351 variants and severe COVID-19 disease in Qatar 

      Chemaitelly, Hiam; Yassine, Hadi M.; Benslimane, Fatiha M.; Al Khatib, Hebah A.; Tang, Patrick; ... more authors (2021 , Article)
      The SARS-CoV-2 pandemic continues to be a global health concern. The mRNA-1273 (Moderna) vaccine was reported to have an efficacy of 94.1% at preventing symptomatic COVID-19 due to infection with ‘wild-type’ variants in a ...

    • Bayesian inference for Pr ( Y<X ) in the exponential distribution based on records 

      Baklizi, Ayman ( Elsevier , 2014 , Article)
      We consider Bayesian estimation of the stress–strength reliability based on record values. The estimators are derived under the squared error loss function in the one parameter as well as two-parameter exponential ...

    • Multi-soliton solutions of the BBM equation arisen in shallow water 

      Alsayyed, O.; Jaradat, H. M.; Jaradat, M. M.M.; Mustafa, Zead ( International Scientific Research Publications , 2016 , Article)
      In this work, multiple soliton solutions and multiple singular soliton solutions are formally derived for the BBM equation. A novel transformation method combined with the Hirota's bilinear method are used to determine the ...

    • New solitary wave and multiple soliton solutions for the time-space coupled fractional mKdV system with time-dependent coefficients 

      Jaradat, H. M; Al-Shara', Safwan; Jaradat, M. M. M; Mustafa, Zead; Alsayyed, O; ... more authors ( American Scientific Publishers , 2016 , Article)
      In this paper, a simplified bilinear method combined with a fractional transform has been used to obtain new multiple soliton solutions for the Fractional coupled modified KdV systems with variable coefficients. These ...

    • Selective hydrogen gas sensor using CuFe 2 O 4 nanoparticle based thin film 

      Haija, Mohammad Abu; Ayesh, Ahmad I.; Ahmed, Sadiqa; Katsiotis, Marios S. ( Elsevier B.V. , 2016 , Article)
      Hydrogen gas sensors based on CuFe2O4 nanoparticle thin films are presented in this work. Each gas sensor was prepared by depositing CuFe2O4 thin film on a glass substrate by dc sputtering inside a high vacuum chamber. ...

    • A new numerical method for heat equation subject to integral specifications 

      Jaradat, H. M.; Jaradat, M. M. M.; Awawdeh, F.; Mustafa, Z.; Alsayyed, O. ( International Scientific Research Publications , 2016 , Article)
      We develop a numerical technique for solving the one-dimensional heat equation that combine classical and integral boundary conditions. The combined Laplace transform, high-precision quadrature schemes, and Stehfest inversion ...

    • Stagnation point flow study with water based nanoparticles aggregation over a stretching sheet: numerical solution 

      Akbar, Noreen Sher; Mustafa, M. T.; Khan, Zafar Hayat ( American Scientific Publishers , 2016 , Article)
      Intention of the current study is to examined the two dimensional stagnation point flow of waterbased nanofluid towards a stretching sheet. To simplify the problem similarity transformations are smearing on basic boundary ...

    • Some common fixed point results of graphs on b-metric space 

      Mustafa, Zead; Jaradat, Husein M.; Jaradat, M. ( International Scientific Research Publications , 2016 , Article)
      The aim of this paper is to present some coincidence point results and common fixed points for pair of self-mappings satisfying generalized contractive condition in the framework of b-metric spaces endowed with a graph. ...

    • Enhancing passive UHF RFID backscatter energy using chirp spread spectrum signals and channel shortening 

      Ben-Jabeur, Taoufik; Kadri, Abdullah; Hazaa, Khalifa Abdulla ( Institute of Electrical and Electronics Engineers Inc. , 2016 , Conference)
      Performance of passive ultrahigh frequency radio-frequency identification (UHF RFID) systems depends on the energy level of the backscattered signal from the RF tag to the RFID reader. In the indoor environment, the ...