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Electrostatic Dust Acoustic Solitons in Pair-Ion-Electron Plasmas

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Chinese Physics Letters 2012年第6期29卷 207-210页

作者： hafeez Ur Rehman Theoretical Plasma Physics Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)P.O.NiloreIslamabadPakistan Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied Sciences(PIEAS)P.O.NiloreIslamabadPakistan

Using the reductive perturbation method,a Korteweg-de Vries (KdV) equation is derived to study the nonlinear properties of electrostatic collisionless dust acoustic solitons in pair-ion-electron (p-i-e) *** Buid model is chosen for positive ions,negative ions,and the fraction of electrons and charged (both positive and negative)dynamic dust *** is realized that electrostatic hump structures can be found when the dust particles are positively charged,and electrostatic dip structures can be detected for negatively charged dust *** solutions for these dust acoustic solitous are plotted and their characteristics are *** is found that the amplitude and width of the electrostatic dust acoustic solitons increase when the density of the dust particles and/or the temperature of the negative ions increases,and that the amplitude and width of these solitons decrease when the temperature of the positive ions *** pair-ion plasmas mimic electron-positron plasmas,our results might be helpful in understanding the nonlinear dust acoustic solitary waves in super dense astronomical bodies like neutron stars.

关键词： particles electrostatic solitons

Designing Bayesian Two-Sided group Chain Sampling Plan for gamma Prior Distribution

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Computer Systems Science & Engineering 2023年第2期44卷 1069-1079页

作者： Waqar hafeez Nazrina Aziz School of Quantitative of Sciences Universiti Utara MalaysiaSintok06010Malaysia Institute of Strategic Industrial Decision Modelling(ISIDM) Universiti Utara MalaysiaSintok06010Malaysia

Acceptance sampling is used to decide either the whole lot will be accepted or rejected,based on inspection of randomly sampled items from the same *** an alternative to traditional sampling plans,it is possible to use Baye-sian approaches using previous knowledge on process *** study pre-sents a Bayesian two-sided group chain sampling plan(BTSgChSP)by using various combinations of design *** BTSgChSP,inspection is based on preceding as well as succeeding *** function is used to derive the probability of lot acceptance based on defective and non-defective *** distribution is considered as a suitable prior for Poisson *** quality regions are found,namely:(i)quality decision region(QDR),(ii)probabil-istic quality region(PQR),(iii)limiting quality region(LQR)and(iv)indifference quality region(IQR).Producer’s risk and consumer’s risk are considered to esti-mate the quality regions,where acceptable quality level(AQL)is associated with producer’s risk and limiting quality level(LQL)is associated with consumer’s ***,AQL and LQL are used in the selection of design parameters for *** values based on all possible combinations of design parameters for BTSgChSP are presented and inﬂection points’values are ***ﬁnding exposes that BTSgChSP is a better substitute for the existing plan for industrial practitioners.

关键词： Bayesian acceptance sampling poisson distribution gamma distribution producer’s risk consumer’s risk

Exome sequencing identifies a likely causative variant in 53%of families with ciliopathy-related features on renal ultrasound after excluding NPHP1 deletions

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genes & Diseases 2024年第5期11卷 40-43页

作者： Konstantin Deutsch Verena Klambt Thomas M.Kitzler Tilman Jobst-Schwan Ronen Schneider Florian Buerger Steve Seltzsam Sherif El Desoky Jameela A.Kari Farkhanda hafeez Maria Szczepanska Loai A.Eid Hazem S.Awad Muna Al-Saffar Neveen A.Soliman Velibor Tasic Camille Nicolas-Frank Kirollos Yousef Luca M.Schierbaum Sophia Schneider Abdul Halawi Izzeldin Elmubarak Katharina Lemberg Shirlee Shril Shrikant M.Mane Nancy Rodig Friedhelm Hildebrandt Division of Nephrology Department of PediatricsBoston Children’s HospitalHarvard Medical SchoolBostonMA 02215USA Department of Pediatric gastroenterology Nephrology and Metabolic DiseasesCharite Universitatsmedizin BerlinBerlin 13353Germany Berlin Institute of Health at Charitee Universitatsmedizin Berlin BIH Biomedical Innovation AcademyBIH Charite Clinician Scientist ProgramBerlin 10178Germany Department of Nephrology and Hypertension FriedrichAlexander-Universitat Erlangen-NurnbergErlangen 91054Germany Department of Pediatrics Faculty of Medicine King Abdulaziz UniversityPediatric Nephrology Center of ExcellenceKing Abdulaziz University HospitalJeddah 21589Saudi Arabia Department of Pediatric Nephrology The Children’s Hospital and Institute of Child HealthLahore 54000Pakistan Department of Pediatrics Faculty of Medical Sciences in ZabrzeMedical University of Silesia in KatowiceKatowice 40-752Poland Dubai Hospital and Al-Jalila Children’s Specialty Hospital Kidney Center of ExcellenceDubai 4545United Arab Emirates Department of genetics and genomics UAE UniversityAbu Dhabi 15551United Arab Emirates Department of Pediatrics Division of Genetics and GenomicsBoston Children’s HospitalHarvard Medical SchoolBostonMA 02215USA Department of Pediatrics Center of Pediatric Nephrology and TransplantationKasr Al Ainy School of MedicineCairo UniversityCairo 11562Egypt Egypt Center for Research and Regenerative Medicine(ECRRM) Cairo 11511Egypt Medical Faculty Skopje University Children’s HospitalSkopje 1000North Macedonia Department of genetics Yale University School of MedicineNew HavenCT 06520USA

Nephronophthisis-related ciliopathies(NPHP-RC)represent one of the most common causes of chronic kidney disease in the first three decades of life and are characterized by a broad genetic and clinical heterogeneity.1 To date,more than 90 genes have been identified that cause autosomalrecessive NPHP-RC if mutated,accounting for up to 60%of cases.1 Among these,homozygous deletions of NPHP1 are the most common *** genes localize to primary cilia,basal bodies,or the centrosome and lead to a primary ciliary disruption if mutated,thereby causing a broad phenotypical spectrum.1 Patients that suffer from NPHP-RC can either have an isolated renal phenotype,such as polyuria,polydipsia,decreased urinary concentration ability,and secondary enuresis due to loss of tubular function,or present with extrarenal symptoms including retinal degeneration,cerebellar vermis hypoplasia,or hepatic *** are often diagnosed in early adolescence,reaching end-stage renal disease before 25 years of age,but early onset and rapidly progressive forms of NPHP-RC also exist.1 Renal ultrasound indicates kidneys of normal or reduced renal length with increased echogenicity and corticomedullary cysts.

关键词： degeneration urinary likely

Violence study of healthcare workers and systems in the Caribbean:ViSHWaS-Caribbean study

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World Journal of Methodology 2024年第3期14卷 106-118页

作者： Reshon Hadmon Daniella Myriam Pierre Akshat Banga Jacques W Clerville Hans Mautong Precious Akinsanya Rajat Das gupta Sama Soliman Tolupe M Hunjah Bamidele A Hunjah hafeez Hamza Ruman Khurshid Qasba Faisal A Nawaz Salim Surani Rahul Kashyap Department of Medicine St.George University School of MedicineGrenada FZ818West Indies Department of Research Global Remote Research Scholar ProgramSt PaulMN 55101United States Department of Public Health Cuny Graduate School of Public Health and Health PolicyNew YorkNY 10027United States Department of Internal Medicine Sawai Man Singh Medical CollegeJaipur 302004India School of Public Health Georgia State UniversityAtlantaGA 30302United States Department of Sociology and Demography School of HealthUniversidad de Especialidades Espiritu SantoSamborondon 092301Ecuador Department of Medicine Holy Name Medical CenterTeaneckNJ 07666United States Department of Epidemiology and Biostatistics University of South CarolinaColumbiaSC 29208United States Department of Medicine Pavlov First State Medical University of St PetersburgSankt-Peterburg 197022Russia Department of Medicine University of SuffolkIpswich IP41QJUnited Kingdom Department of Medicine Unicaf University of ZambiaLusaka 20842Zambia Department of Pharmacy School of PharmacyGirne 99428Cyprus Department of Medicine Sher-i-KashmirInstitute of Medical ScienceSrinagar 190011India Department of Psychiatry Al Amal Psychiatric HospitalEmirates Health ServicesDubaiUnited Arab Emirates Department of Medicine and Pharmacology Texas A and M UniversityCollege StationTX 77843United States Anesthesiology and Critical Care Mayo ClinicRochesterMN 55905United States Department of Research Wellspan HealthYorkPA 17403United States

BACKgROUND Violence against healthcare workers(HCWs)in the Caribbean continues to prevail yet remains *** aim is to determine the cause,traits,and consequences of violence on HCWs in the *** To determine the cause,traits,and consequences of violence on HCWs in the *** This research adopted an online cross-sectional survey approach,spanning over eight weeks(between June 6th and August 9th,2022).The survey was generated using Research Electronic Data Capture forms and followed a snowballing strategy to contact individuals using emails,social media,text messages,*** regression analysis was performed to evaluate the variables that influence violence,including gender,age,years of experience,institution type,and night shift *** The survey was completed by 225 *** comprised 61%.Over 51%of respondents belonged to the 21 to 35 age ***(n=61),Haiti(n=50),and grenada(n=31)had the most *** HCWs(49%)worked for government academic institutions,followed by community hospitals(23%).Medical students(32%),followed by attending physicians(22%),and others(16%)comprised the most common cadre of *** 39%of the participants reported experiencing violence themselves,and 18%reported violence against colleague(s).Verbal violence(48%),emotional abuse(24%),and physical misconduct(14%)were the most common types of *** 63%of respondents identified patients or their relatives as the most frequent *** logistic regression analyses demonstrated that female gender(OR=2.08;95%CI:1.16-3.76,P=0.014)and higher frequency of night shifts(OR=2.22;95%CI:1.08-4.58,P=0.030)were associated with significantly higher odds of experiencing *** than 50%of HCWs felt less motivated and had decreased job satisfaction post-violent *** A large proportion of HCWS in the Caribbean are exposed to violence,yet the phenomenon remains *** a result,HCWs’job s

关键词： ViSHWaS Healthcare workers Violence Survey Workplace violence Caribbean Cross-sectional study

Four-axis trochoidal toolpath planning for rough milling of aero-engine blisks

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Chinese Journal of Aeronautics 2019年第8期32卷 2009-2016页

作者： Ming LUO Ce HAH Hafiz M.hafeez Key Laboratory of Contemporary Design and Integrated Manufacturing Technology(Northwestern Polytechnical University) Ministry of EducationXi’an 710072China Beijing Jingdiao group Co. Ltd.Beijing 102308China

The Blade Integrated Disk(Blisk) is one of the key components in the aero-engine, it is generally manufactured by the multi-axis milling and almost 90% raw materials are removed. To avoid the full immersion of a cutter in the rough machining of a blisk channel, the trochoidal milling is a promising strategy since it can keep a small immersion angle in the rough milling process while maintaining the high machining efficiency. However, while toolpaths are being planned for the trochoidal milling process, the conventional methods are mainly for the planar machining area with fixed tool orientations, which cannot be used for complex channels where the multi-axis machining should be employed. To this end, this paper presents a four-axis trochoidal toolpath planning method with a ball-end cutter, and thus the blisk channel can be machined *** this to happen, the trochoidal paths are planned in the parametric domain and then mapped into the physical domain, with tool orientations controlled by the quaternion interpolation method to have smooth tool movement along the toolpaths. Both geometric simulation and physical milling experiments of the proposed method have convincingly demonstrated the validation of the proposed method.

关键词： Aero-engine Blisk Machining Toolpath planning Trochoidal milling

Rotational flow of Oldroyd-B nanofluid subject to Cattaneo-Christov double diffusion theory

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Applied Mathematics and Mechanics(English Edition) 2020年第7期41卷 1083-1094页

作者： A.hafeez M.KHAN A.AHMED J.AHMED Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

A nanofluid is composed of a base fluid component and nanoparticles, in which the nanoparticles are dispersed in the base fluid. The addition of nanoparticles into a base fluid can remarkably improve the thermal conductivity of the nanofluid, and such an increment of thermal conductivity can play an important role in improving the heat transfer rate of the base fluid. Further, the dynamics of non-Newtonian fluids along with nanoparticles is quite interesting with numerous industrial applications. The present predominately predictive modeling studies the flow of the viscoelastic Oldroyd-B fluid over a rotating disk in the presence of nanoparticles. A progressive amendment in the heat and concentration equations is made by exploiting the Cattaneo-Christov heat and mass flux expressions. The characteristic of the Lorentz force due to the magnetic field applied normal to the disk is studied. The Buongiorno model together with the Cattaneo-Christov theory is implemented in the Oldroyd-B nanofluid flow to investigate the heat and mass transport mechanism. This theory predicts the characteristics of the fluid thermal and solutal relaxation time on the boundary layer flow. The von K′arm′an similarity functions are utilized to convert the partial differential equations(PDEs) into ordinary differential equations(ODEs). A homotopic approach for obtaining the analytical solutions to the governing nonlinear problem is carried out. The graphical results are obtained for the velocity field, temperature, and concentration distributions. Comparisons are made for a limiting case between the numerical and analytical solutions, and the results are found in good agreement. The results reveal that the thermal and solutal relaxation time parameters diminish the temperature and concentration distributions, respectively. The axial flow decreases in the downward direction for higher values of the retardation time parameter. The impact of the thermophoresis parameter boosts the temperature di

关键词： Oldroyd-B nanofluid rotating disk magnetohydrodynamic(MHD) Cattaneo-Christov theory analytical solution

High Voltage Direct Current (HVDC) Transmission: Future Expectation for Pakistan

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CSEE Journal of Power and Energy Systems 2019年第1期5卷 82-86页

作者： Kamran hafeez Shahid A.Khan Electrical Engineering Department CIIT Islamabad campus Pakistan

An HVDC transmission system for bulk power transfer over longer distance offers numerous advantages over an alternating current(AC)transmission system,such as direct integration of networks operating at different frequencies,comparatively low line losses on account of constant current and absence of *** paper presents details about HVDC power transmission systems and power converter *** concerning integration of electrical power generated by alternate sources(i.e.,wind,onshore and offshore)into the national grid of Pakistan using HVDC technology are also *** studies revealed that the energy crisis of countries like Pakistan can be mitigated to a larger extent with the use of HVDC transmission systems.

关键词： HVDC renewable energy transmission systems wind Energy

Von Kármán rotating flow of Maxwell nanofluids featuring the Cattaneo-Christov theory with a Buongiorno model

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Applied Mathematics and Mechanics(English Edition) 2020年第8期41卷 1195-1208页

作者： A.AHMED M.KHAN J.AHMED A.hafeez Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan Department of Basic Sciences University of Engineering and TechnologyTaxila 47050Pakistan

This research paper analyzes the transport of thermal and solutal energy in the Maxwell nanofluid flow induced above the disk which is rotating with a constant angular *** significant features of thermal and solutal relaxation times of fluids are studied with a Cattaneo-Christov double diffusion theory rather than the classical Fourier’s and Fick’s laws.A novel idea of a Buongiorno nanofluid model together with the Cattaneo-Christov theory is introduced for the first time for the Maxwell fluid flow over a rotating ***,the thermal and solutal distributions are controlled with the impacts of heat source and chemical *** classical von Karman similarities are used to acquire the non-linear system of ordinary differential equations(ODEs).The analytical series solution to the governing ODEs is obtained with the well-known homotopy analysis method(HAM).The validation of results is provided with the published results by the comparison *** graphically presented outcomes for the physical problem reveal that the higher values of the stretching strength parameter enhance the radial velocity and decline the circumferential *** increasing trend is noted for the axial velocity profile in the downward direction with the higher values of the stretching strength *** higher values of the relaxation time parameters in the Cattaneo-Christov theory decrease the thermal and solutal energy transport in the flow of Maxwell *** higher rate of the heat transport is observed in the case of a larger thermophoretic force.

关键词： Maxwell fluid nanoparticle Cattaneo-Christov theory rotating disk homotopy analysis method(HAM)

Effect of thermomechanical cyclic quenching and tempering treatments on microstructure,mechanical and electrochemical properties of AISI 1345 steel

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 688-698页

作者： Muhammad Arslan hafeez Ameeq Farooq Kaab Bin Tayyab and Muhammad Adnan Arshad School of Civil and Environmental Engineering National University of Sciences and TechnologyIslamabad 44000Pakistan Department of Metallurgy&Materials Engineering University of the Punjab54590 LahorePakistan

Thermomechanical cyclic quenching and tempering(TMCT)can strengthen steels through a grain size reduction *** effect of TMCT on microstructure,mechanical,and electrochemical properties of AISI 1345 steel was *** samples heated to 1050℃,rolled,quenched to room temperature,and subjected to various cyclic quenching and tempering heat treatments were named TMCT-1,TMCT-2,and TMCT-3 samples,*** analysis revealed that microstructures of all the treated samples contained packets and blocks of well-refined lath-shaped martensite and retained austenite phases with varying grain sizes(2.8–7.9μm).Among all the tested samples,TMCT-3 sample offered an optimum combination of properties by showing an improvement of 40%in tensile strength and reduced 34%elongation compared with the non-treated *** results were in good agreement with mechanical tests as the TMCT-3 sample exhibited a 51%improvement in indentation hardness with almost identical reduced elastic modulus compared with the non-treated *** electrochemical properties were analyzed in 0.1 M NaHCO_(3) solution by potentiodynamic polarization and electrochemical impedance *** a result of TMCT,the minimum corrosion rate was 0.272 mm/a,which was twenty times less than that of the nontreated *** impedance results showed the barrier film mechanism,which was confirmed by the polarization results as the current density decreased.

关键词： thermomechanical treatment cyclic heat-treatment nanoindentation potentiodynamic polarization electrochemical impedance spectroscopy