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Dynamics of Particles Around a Regular Black Hole with Nonlinear Electrodynamics

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Communications in Theoretical Physics 2016年第11期65卷 509-516页

作者： Abdul jawad Farhad Ali Mubasher Jamil Ujjal Debnath Department of Mathematics COMSATS Institute of Information Technology Department of Mathematics Kohat University of Science and Technology Department of Mathematics School of Natural Sciences (SNS) National University of Sciences and Technology (NUST) Department of Mathematics Indian Institute of Engineering Science and Technology

We investigate the dynamics of a charged particle being kicked off from its circular orbit around a regular black hole by an incoming massive particle in the presence of magnetic field. The resulting escape velocity, escape energy and the effective potential are analyzed. It is shown that the presence of even a very weak magnetic field helps the charged particles in escaping the gravitational field of the black hole. Moreover the effective force acting on the particle visibly reduces with distance. Thus particle near the black hole will experience higher effective force as compared to when it is far away.

关键词： center of mass energy escape velocity electrodynamics regular black hole

Reinforcement Learning-Based Optimization for Drone Mobility in 5G and Beyond Ultra-Dense Networks

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Computers, Materials & Continua 2021年第9期68卷 3807-3823页

作者： jawad Tanveer Amir Haider Rashid Ali Ajung Kim School of Optical Engineering Sejong UniversitySeoul05006Korea School of Intelligent Mechatronics Engineering Sejong UniversitySeoul05006Korea

Drone applications in 5th generation(5G)networks mainly focus on services and use cases such as providing connectivity during crowded events,human-instigated disasters,unmanned aerial vehicle traffic management,internet of things in the sky,and situation awareness.4G and 5G cellular networks face various challenges to ensure dynamic control and safe mobility of the drone when it is tasked with delivering these *** drone can fly in three-dimensional *** drone connectivity can suffer from increased handover cost due to several reasons,including variations in the received signal strength indicator,co-channel interference offered to the drone by neighboring cells,and abrupt drop in lobe edge signals due to antenna *** baseline greedy handover algorithm only ensures the strongest connection between the drone and small cells so that the drone may experience several *** for fast environment learning,machine learning techniques such as Q-learning help the drone fly with minimum handover cost along with robust *** this study,we propose a Q-learning-based approach evaluated in three different *** handover decision is optimized gradually using Q-learning to provide efficient mobility support with high data rate in time-sensitive applications,tactile internet,and haptics *** results demonstrate that the proposed algorithm can effectively minimize the handover cost in a learning *** work presents a notable contribution to determine the optimal route of drones for researchers who are exploring UAV use cases in cellular networks where a large testing site comprised of several cells with multiple UAVs is under consideration.

关键词： 5G dense network small cells mobility management reinforcement learning performance evaluation handover management

Temporal Correlation-Based Spatial Filtering of Rician Noise for Functional MRIs

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Chinese Physics Letters 2012年第1期29卷 287-290页

作者： Amir.A.Khaliq I.M.Qureshi jawad.A.Shah Department of Electronic Engineering International Islamic UniversityIslamabadPakistan Air University ISSSIslamabadPakistan

A novel correlation-based filter is presented for de-noising functional magnetic resonance imaging (fMRI) *** correlation-based exponential weights are defined for spatial smoothing of the data,with bias reduction using estimated noise *** proposed scheme is tested on simulated and real fMRI ***,the results are compared with conventional *** method is found to be effectively suppressing the Rician noise in fMRI data,while improving the SNR.

关键词： weights smoothing Spatial

Matter accretion onto Einstein-aether black holes via well-known fluids

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Chinese Physics C 2020年第6期44卷 182-196页

作者： M.Umair Shahzad Rafaqat Ali Abdul jawad Shamaila Rani Department of Mathematics University of OkaraOkaraPakistan Department of Mathematics COMSATS University IslamabadLahore-CampusPakistan

We study matter accretion onto Einstein-aether black holes by adopting the Hamiltonian *** general solution of accretion is discussed using the isothermal equation of *** types of fluids are considered,including ultra-relativistic,ultra-stiff,sub-relativistic,and radiation fluids,and the accretion process onto Einstein-aether black holes is *** behavior of the fluid flow and the existence of critical points is investigated for Einstein-aether black *** further discuss the general expression and behavior of polytropic fluid onto Einstein-aether black *** most important feature of this work is the investigation of the mass accretion rate of the above-mentioned fluids and the comparison of our findings with the Schwarzschild black hole,which generates particular ***,the maximum mass accretion rate occurs near the Killing and universal horizons,and the minimum accretion rate lies between them.

关键词： black hole accretion homo-clinic orbits

Transmission dynamics of Hand-Foot-Mouth Disease with partial immunity through non-integer derivative

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生物数学学报:英文版 2023年第6期16卷 149-173页

作者： Rashid Jan Salah Boulaaras Sultan Alyobit Muhammad jawad Department of Mathematics University of Swabi Swabi 23561Khyber PakhtunkhwaPakistan Department of Mathematics College of Sciences and Arts Qassim UniversityAr RassSaudi Arabia Department of Mathematics College of Science 8 Arts King Abdulaziz UniversityRabighSaudi Arabia

In this paper,we formulate the transmission phenomena of Hand-Foot-Mouth Disease(HFMD)through non-integer *** interrogate the biological meaningful results of the recommended system of *** basic reproduction number is determined through next generation method and the impact of different parameters on the reproduction number is examined with the help of partial rank correlation coeficient(PRCC)*** addition,we concentrated on qualitative analysis and dynamical behavior of HFMD ***'s and Schaefer's fixed-point theorems are used to analyze the uniqueness and existence of the solution of the proposed HFMD *** HFMD system's Ulam-Hyers stability has been confirmed to be *** highlight the impact of the parameters on the dynamics of HFMD,we performed several simulations through numerical scheme to conceptualize the transmission route of the *** be more specific,numerical simulations are used to visualize the effect of input parameters on the systems *** have shown the key input parameters of the system for the control of infection in the society.

关键词： Hand-Foot-Mouth Disease fractional derivatives mathematical model threshold parameter numerical scheme dynamical behavior

Performance Enhancement of Praseodymium Doped Fiber Amplifiers

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Computers, Materials & Continua 2022年第12期73卷 5411-5422页

作者： Abdullah G.Alharbi jawad Mirza Mehak Raza Salman Ghafoor Department of Electrical Engineering Faculty of EngineeringJouf UniversitySakaka42421Saudi Arabia SEECS Photonics Research Group Islamabad44000Pakistan Institute of Space Technology Islamabad44000Pakistan School of Electrical Engineering and Computer Science(SEECS) National University of Sciences and Technology(NUST)Islamabad44000Pakistan

In this paper,we report a simulation study on the performance enhancement of Praseodymium doped silica fiber amplifiers(PDFAs)in O-band(1270-1350 nm)in terms of small signal gain,power conversion efficiency(PCE),and output optical power by employing bidirectional *** PDFA performance is examined by optimizing the length of Praseodymium doped silica fiber(PDF),its mode-field diameter(MFD)and the concentration of Pr^(3+).A small-signal peak gain of 56.4 dB,power conversion efficiency(PCE)of 47%,and output optical power of around 1.6 W(32 dBm)is observed at optimized parameters for input signal wavelength of 1310 *** noise figure(NF)of 4.1 dB is observed at input signal wavelength of 1310 ***,the effect of varying the pump wavelength and pump power on output optical power of the amplifier and amplified spontaneous emission(ASE)noise is also investigated,***,the impact of ion-ion interaction(up-conversion effect)on small-signal gain of the amplifier is also studied by considering different values of up-conversion coefficient.

关键词： Praseodymium-doped fiber doped fiber amplifiers optical amplification mode field diameter noise figure

Return and Volatility Connectedness between Stock Markets and Macroeconomic Factors in the G-7 Countries

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Journal of Systems Science and Systems Engineering 2019年第1期28卷 1-36页

作者： Ghulam Abbas Shawkat Hammoudeh Syed jawad Hussain Shahzad Shouyang Wang Yunjie Wei School of Economics and Management University of Chinese Academy of Sciences Beijing 100190 China Sukkur Institute of Business Administration Sukkur Sindh-65200 Pakistan Lebow College of Business Drexel University Philadelphia United States Energy and Sustainable Development (ESD) Montpellier Business School Montpellier France Energy and Sustainable Development (ESD) Montpellier Business School Montpellier France Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Center for Forecasting Science Chinese Academy of Sciences Beijing 100190 China

We examine the relationship between return and volatility of the stock markets and macroeconomic fundamentals for the G-7 countries by using monthly data ranging from July 1985 to June 2015. To meet this end, we apply the spillover index approach based on the generalized VAR framework developed by Diebold and Yilmaz (2012, 2014). The empirical analysis shows strong interactions between the returns and volatilities of the G-7 stock markets and the considered set of corresponding macroeconomic factors including industrial production, money supply, interest rates, inflation, oil prices and exchange rates. The return and volatility spillover transmission/reception dynamics of the relationships between these stock markets and the macroeconomic fundamentals have changed after the global financial crisis of 2008. Our findings provide useful insights for investors and policy makers concerned with the unprecedented swings in the stock markets of G-7 countries.

关键词： G-7 return volatility connectedness macroeconomic factors generalized VAR

Inflammatory response related scoring systems in assessing the prognosis of patients with pancreatic ductal adenocarcinoma:a systematic review

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Hepatobiliary & Pancreatic Diseases International 2014年第5期13卷 474-481页

作者： jawad Ahmad Nathan Grimes Shahid Farid Gareth Morris-Stiff HPB Surgery Mater Hospital Department of Surgery Kettering General Hospital Department of Surgery Belfast City Hospital

BACKGROUND： Various scoring systems based on assessment of the systemic inflammatory response help assessing the prognosis of patients with pancreatic ductal *** the present systematic review we evaluated the validity of four pre-intervention scoring systems： Glasgow prognostic score（GPS） and its modified version（mGPS）, platelet lymphocyte ratio（PLR）, neutrophil lymphocyte ratio（NLR）, and prognostic nutrition index（PNI）.DATA SOURCES： MOOSE guidelines were followed and EMBASE and MEDLINE databases were searched for all published studies until September 2013 using comprehensive text word and MeSH terms. All identified studies were analyzed, and relevant studies were included in the systematic ***： Six studies were identified for GPS/mGPS with3 reporting statistical significance for GPS/mGPS on both univariate analysis（UVA） and multivariate analysis（MVA）.Two studies suggested prognostic significance on UVA but not MVA, and in the final study UVA failed to show *** studies evaluated the prognostic value of NLR. Six of them reported prognostic significance for NLR on UVA that persisted at MVA in 4 studies, and in the remaining 2 studies NLR was the only significant factor on UVA. In the remaining5 studies, all in patients undergoing resection, there was no significance on UVA. Seven studies evaluated PLR, with only one study demonstrated its prognostic significance on both UVAand MVA, the rest did not show the significance on UVA. Of the two studies identified for PNI, one demonstrated a statistically significant difference in survival on both UVA and MVA, and the other reported no significance for PNI on ***： Both GPS/mGPS and NLR may be useful but further better-designed studies are required to confirm their value. PLR might be little useful, and there are at present inadequate data to assess the prognostic value of PNI. At present, no scoring system is reliable enough to be accepted into routine use for the prognosi

关键词： pancreatic ductal adenocarcinoma Glasgow prognostic score modified Glasgow prognostic score platelet lymphocyte ratio neutrophil lymphocyte ratio prognostic nutrition index

Evaluation of microstructure and mechanical properties of squeeze overcast Al7075-Cu composite joints

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China Foundry 2023年第1期20卷 29-39页

作者： Muhammad Waqas Hanif Ahmad Wasim Muhammad Sajid Salman Hussain Muhammad jawad Mirza Jahanzaib Department of Industrial Engineering University of Engineering and Technology TaxilaPunjabPakistan

Al7075-Cu composite joints were prepared by the squeeze overcast *** effects of melt temperature,die temperature,and squeeze pressure on hardness and ultimate tensile strength(UTS)of squeeze overcast Al7075-Cu composite joints were *** experimental results depict that squeeze pressure is the most significant process parameter affecting the hardness and *** optimal values of UTS(48 MPa)and hardness(76 HRB)are achieved at a melt temperature of 800℃,a die temperature of 250℃,and a squeeze pressure of 90 *** electron microscopy(SEM)shows that fractured surfaces show flatfaced morphology at the optimal experimental ***-dispersive spectroscopy(EDS)analysis depicts that the atomic weight percentage of Zn decreases with an increase in melt temperature and squeeze *** optimal mechanical properties of the Al7075-Cu overcast joint were achieved at the Al2Cu eutectic phase due to the large number of copper atoms that dispersed into the aluminum melt during the solidification process and the formation of strong intermetallic *** relational analysis integrated with the Taguchi method was used to develop an optimal set of control variables for multi-response parametric *** tests were performed to validate the effectiveness of the employed *** manufacturing of squeeze overcast Al7075-Cu composite joints at optimal process parameters delivers a great indication to acknowledge a new method for foundry practitioners to manufacture materials with superior mechanical properties.

关键词： squeeze overcast joints Al7075-Cu composite joints mechanical properties gray relational analysis Taguchi method