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Journal of Minerals and Materials Characterization and Engineering 2011年第13期10卷 1205-1212页

作者： a.a.s. ghazi K. Chandra P.s. Misra Department of Metallurgical and Materials Engineering Indian Institute of Technology Roorkee India.

This present paper investigates the friction and wear properties of friction material developed by ‘Hot Powder Preform Forging’ technique. The conventional technique to manufacture Metallo-ceramic brake pads was successfully and economically tried to replace the above process. Compacting and sintering technology suffers from certain major limitations such as inadequate joining of friction element with backing plate, poor density levels achieved in friction element owing to limited application of pressure during compacting, poor thermal conductivity due to high levels of porosity in the product, poor strength due to segregation of the impurities along prior particle boundaries (PPB’s) and, wide variations in final characteristics due to large number of variables involved. In contrast to these limitations, the present technique can offer brake pads of much simpler chemistry but with improved performance on account of simultaneous application of pressure and temperature and with better control of variables. Fade and recovery studies were carried out on a Krauss machine tester following the Economic Commission for Europe Regulation for replacement brake linings (ECE R-90). μfade, μrecovery, μperformance, % age fade , % age recovery & temperature rise lie within the range for friction materials used for low duty applications. The mechanical properties of these materials were characterized using AsTM standards.

关键词： Friction material Preform forging Brake pads Fade.

Incense smoke(Is)inhalation exposure system:Physicochemical characterization,Is particle deposition and clearance in human airway using MPPD model

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Particuology 2024年第4期87卷 271-285页

作者： Vyas Kumar Hafsa Hashmi Anshita Nasreen ghazi Ansari Jyotsna singh Inhalation Toxicology Facility Regulatory Toxicology GroupCSR-Indian Institute of Toxicology ResearchLucknow22001UPIndi Academy of scientific and Innovative Research(AcssIR) Ghaziabad201002UPIndia Analytical Chemistry Regulatory Toxicology GroupCSIR-Indian Institute of Toxicology ResearchLucknow226001UPIndia

Incense smoke(Is)is source of indoor air pollution and key risk for diverse human *** in-formation is available regarding controlled Is rodent inhalation exposure system and Is particulate matter(PM)deposition in human *** aimed to demonstrate stable IsPM physicochemical parameters of 10 incense products inside the customized whole body inhalation exposure chamber(without animal)connected to smoke generation unit via aerosol mixing *** analyzed for size segregated PM emission,IsPM in vitro aerodynamics(MMAD and GsD determination),fine and ultrafine particle's sEM,sEM-EDX and PAH *** real life exposure scenario by utilizing MMAD,GsD and PM concentration after Tier 1 exposure assessment as key input parameters,IsPM dosimetry in infant(3 months)and adult(21 years male and female)human airways was calculated using multiple-path particle dosimetry(MPPD 3.04)*** median aerodynamic diameter(MMAD)and geo-metric standard deviation(GsD)ranged between 0.55 and 2.10μm and 1.22 to 1.77(polydisperse)***1.0 and PM0.1 showed multiple morphology and presence of heavy and trace *** like acenaphthylene,anthracene,fluorene,naphthalene and phenanthrene were detected(0.84-143.17μg/g).MPPD results showed higher IsPM deposition in pulmonary region and lowest in trachea bronchial *** deposition in tissue was higher in lower,peripheral lung as compared to upper and central lung *** body inhalation exposure system showed stable Is atmosphere(physi-cochemical parameters)indicating the device suitability in future inhalation *** IsPM deposition fraction and clearance da.a.s.owed deep lung penetrating and retention behavior with higher risk in infant followed by female and then *** modeled particle deposition and clearance data may be useful in risk assessment analysis of Is.

关键词： Inhalation Incense smoke Multiple-path particle dosimetry(MPPD) Particle deposition Particulate matter(PM) Mass median aerodynamic diameter (MMAD) Human airway

Web GIs-Based Temporal Analysis of Climatic Factors Impacting Heat stroke in Karachi

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Journal of Geographic Information system 2024年第1期16卷 61-69页

作者： Ali Atif Mahnoor Rehman Muhammad Butt syed Mahmood shahid ghazi Rashid Mehmood Department of Management Victoria University Sydney Australia Department of Geography Government College University Lahore Pakistan Department of space science University of the Punjab Lahore Pakistan Centre of Geographic Information system University of The Punjab Lahore Pakistan

This study focuses on the impact of climate change, specifically the increasing threat of heatwaves, in Pakistan, with a particular emphasis on the city of Karachi. The Pakistan Meteorological Department (PMD) analysed a century of climatic data to reveal warming trends, attributing them to human-induced factors. The vulnerability of Pakistan to climate change is highlighted, given its warm climate and location in a region where temperature increases are expected to surpass global averages. The study examines the past three decades, noting a significant rise in the frequency of hot days, especially in Karachi, where heatwaves have become more prevalent. The aims and objectives of the study involve identifying temporal changes in temperature, rainfall, humidity, and wind speed from 1984 to 2014 in Karachi. The literature review emphasizes the health implications of heatwaves, citing increased mortality during such events globally. The study incorporates a comprehensive temporal analysis, addressing gaps in previous research by considering multiple climate indicators responsible for heatwaves. The methodology involves statistical analyses, including linear regression and Pearson correlation, applied to temperature data and urbanization parameters. Results indicate an increasing trend in heat index temperature, with heatwave vulnerability peaking in the last three decades. Heat Index Temperature Anomalies show a clear surge, emphasizing the need for new indices to control critical heat stress conditions. The study concludes that tropical climate variability, particularly heat index, is linked to extreme hot days, urging measures to reduce population vulnerability. The findings underscore the importance of policy strategies, such as integrated coastal zone management, to mitigate the adverse health effects of heatwaves in Karachi’s vulnerable population.

关键词： IPCC Heat Wave Heat Index PMD

On some properties of the bibasic Humbert hypergeometric functions Ξ_(1) and Ξ_(2)

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Applied Mathematics(A Journal of Chinese Universities) 2023年第4期38卷 614-630页

作者： CAI Qing-bo ghazi s.Khammash shimaa I.Moustafa Ayman shehata Provincial Key Laboratory of Data-Intensive Computing Key Laboratory of Intelligent Computing and Information ProcessingSchool of Mathematics and Computer ScienceQuanzhou Normal UniversityQuanzhou 362000China Department of Mathematics Al-Aqsa UniversityGazaGaza StripPalestine Department of Mathematics Faculty of ScienceAssiut UniversityAssiut 71516Egypt Department of Mathematics Unaizah College of Science and ArtsUnaizah 56264Qassim UniversityBuraydah 52571QassimSaudi Arabia

The main object of this paper is to deduce the bibasic Humbert functions Ξ_(1) and Ξ_(2)some interesting results and elementary summations technique that was successfully employed,q-recursion,q-derivatives relations,the q-differential recursion relations,the q-integral representations for Ξ_(1) and Ξ_(2)are *** summation formula derives a list of p-analogues of transformation formulas for bibasic Humbert functions that have been studied,also some hypergeometric functions properties of some new interesting special cases have been given.

关键词： q-calculus bibasic Humbert hypergeometric functions q-derivative

Comparison of DsHA-based response spectrum with design response spectrum of building code of Pakistan(BCP-sP-2007)for a site in Muzaffargarh area,Pakistan

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Earthquake science 2022年第4期35卷 280-292页

作者： Naseer Ahmed shahid ghazi Institute of Geology University of PunjabLahore 54000Pakistan Centre for Geographic Information system University of PunjabLahore 54000Pakistan

The building code of any country is considered to be a basic technical guidance document for the seismic design of ***,building codes are typically developed for the whole country,without considering site specific models that incorporate detailed site-specific ***,the adequacy of the design spectrum for building codes may sometimes be *** study the sufficiency of the building codes of Pakistan(BCP-sP-2007),a deterministic seismic hazard analysis(DsHA)based spectrum was developed for a site in the Muzaffargarh area,Pakistan,using an updated earthquake catalogue,seismic source model,and a next generation attenuation model(NGA-WEsT-2).Further,an International Building Code(IBC-2000)spectrum was developed for the study area to compare the *** DsHA-based response spectrum resulted in a peak ground acceleration(PGA)value of 0.21 g for the Chaudwan *** evaluation of BCP-sP-2007 and IBC-2000 spectra provided a critical assessment for analyzing the associated margins.A comparison with the DsHA-based response spectrum showed that the BCP-sP-2007 design spectrum mostly overlapped with the DsHA spectrum unlike ***,special attention is needed for designing buildings in the study area when considering earthquake periods longer than 1 s,and the BCP-sP-2007 spectrum can be enhanced when considering a period range of 0.12-0.64 ***,BCP-sP-2007 is based on a probabilistic approach and its comparison with deterministic results showed the significance of both methods in terms of design.

关键词： deterministic seismic hazard analysis earthquakes probabilistic seismic hazard analysis building code response spectrum

Dynamic evaluation of jack-up platform structure under wave, wind, earthquake and tsunami loads

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Journal of Ocean Engineering and science 2022年第1期7卷 41-57页

作者： Zaid Mohammed ghazi Imad shakir Abbood Farzad Hejazi Department of Civil Engineering Universiti Putra MalaysiaMalaysia Engineering Affairs Department Sunni Endowment DiwanBaghdadIraq

Nowa.a.s.the demand for using jack-up platforms to carry out a large percentage of deep-water oil and gas exploration is steadily *** response of jack-up platforms to the severe dynamic loads that may be encountered during the structure life is not examined ***,this study attempts to investigate the response of jack-up platforms performance under the effect of dynamic loads due to wave,wind,earthquake and tsunami forces using the finite element method for two models with the lowest and highest hull *** jack-up platform is located in the Gulf of *** ac-celerations are applied to the model in high and moderate seismic *** addition,tsunami waves are applied to the platform in three different directions at 0°,45°and 90°.This study utilised Airy’s linear wave approach to assess the surface elevations and wave *** reference wind velocity is 10 knots at 10 m over the mean water *** indicate that the dynamic response of the structure is affected by the height of the platform and by the increase of the platform hull *** combination of the El-Centro earthquake,dead and live loads provides the major impact on the platform at the lowest(70 m)and highest(85 m)hull *** comparison of all result proves that the jack-up platform hull under high earthquake intensity and tsunami waves with 45°has experienced maximum ***,raising the deck will increase the response of the dynamic load and displacements but will negatively affect the platform.

关键词： Offshore structures Earthquake Dynamic excitation Jack-up platform Tsunami seismic zone

spatial regression approach to estimate synthetic unit hydrograph by geomorphic characteristics of watersheds in arid regions

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Journal of Arid Land 2020年第6期12卷 950-963页

作者： Luminda N GUNAWARDHANA ghazi A AL-RAWAs Mahad s BAAWAIN Department of Civil and Architectural Engineering College of EngineeringSultan Qaboos UniversityOman

Rainfall-runoff relationship in arid regions is unique and challenging to *** for bridging the hydro-meteorological knowledge gap for planning,designing and managing water resources is therefore vitally *** objective of this study is to develop a method for estimating unit hydrograph at reasonably finer time resolutions(10-min and 1-h)which can be easily adaptable by practitioners at subcatchment levels,especially when the focus area is *** wadi-flow at 5-min interval and tipping bucket rainfall measurements at 1-min interval were obtained to cover 10 major watersheds in *** deconvolution method was applied to derive the unit hydrographs(UHs)from wadi-flow and excess *** catchment characteristics such as the watershed area,length of the main wadi and the length to the centroid of the catchment area were derived from digital elevation model(DEM)*** whole study area was then divided into 515 sub-catchments with various shapes and sizes.A strong relationship was found between the wadi length and the length to the centroid of the catchment area(R2>0.89).This relationship was then adopted to simplify the classical snyder method to determine ***,several parameters of the snyder method were calibrated to the arid environment by matching the peak-flow,lag-time and three time-widths(75%,50%and 30%of the peak-flow)of 10-min and 1-h UHs with physical characteristics of the *** developed relationships were validated with independent rainfall and wadi-flow *** indicate that the calibrated parameters in these arid watersheds are quite distinct from those suggested for other regions of the world.A marked difference was found between the 10-min UHs estimated by the s-hydrograph method and the deconvolution ***,it is concluded that a method depends on natural hydro-meteorological conditions would be more practical in arid *** proposed methodology can be used for water resources ma

关键词： deconvolution method s-hydrograph method snyder method DEM data river length

Numerical study of Temperature and Electric Field Effects on the Total Optical Absorption Coefficient in the Presence of Optical Inter-Conduction-subband Transitions in InGaN/GaN single Parabolic Quantum Wells

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1253-1261页

作者： Redouane En-nadir Haddou El-ghazi Anouar Jorio Izeddine Zorkani Hassan Abboudi Fath Allah Jabouti LPs Sidi Mohamed Ben Abdullah UniversityFez30000Morocco ENsAM Hassan-II UniversityCasablanca20470Morocco

In this paper,we theoretically investigate the total optical coefficient(TOAC)considering 1s-2P and 2s-2P conduction subband transitions in a single parabolic quantum well(sPQW)with an on-center hydrogen-like *** the framework of the effective-mass approximation,the schrödinger equation is solved numerically to obtain the eigenvalues and their corresponding eigenvectors using the finite difference *** calculations are performed for finite confinement potential height,taking into account the dielectric and effective mass mismatches between GaN and InGaN materials under the considered electric field and temperature *** temperature dependence of the effective mass,dielectric constant and band gap energy are obtained *** the one hand,the results show that a significant shift is produced with the variation of both the temperature and the intensity of the electric *** the other hand,the absorption spectrum is shifted to lower energies with increasing both electric field strength and ***,its amplitude is enhanced with an increase in the intensity of the electric field,and show a slight drop with increasing temperature for the two optical transitions *** results show that such parameters can be used to adjust the optical properties of single parabolic Quantum Well for solar cell applications.

关键词： TOAC optical transitions sPQW electric field intensity temperature hydrogenic-impurity

Power Quality Assessment of Voltage Positive Feedback Based Islanding Detection Algorithm

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Journal of Modern Power systems and Clean Energy 2020年第4期8卷 787-795页

作者： Reza Bakhshi-Jafarabadi Reza ghazi Javad sadeh Electrical Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran

Islanding refers to a condition where distributed generators(DGs)inject power solely to the local load after electrical separation from power *** islanding detection methods(IDMs)categorized into remote,active,and passive groups have been reported to detect this undesirable *** active techniques,a disturbance is injected into the DG’s controller to drift a local yardstick out of the permissible *** this disturbance leads to more effective detections even in well-balanced island,it raises the total harmonic distortion(THD)of the output current under the normal operation *** paper analyzes the power quality aspect of the modified sliding mode controller as a new active IDM for grid-connected photovoltaic system(GCPVs)with a string *** performance is compared with the voltage positive feedback(VPF)method,a well-known active *** evaluation is carried out for a 1 k Wp GCPVs in MATLAB/simulink platform by measuring the output current harmonics and THD as well as the efficiency under various penetration and disturbance *** output results demonstrate that since the proposed disturbance changes the amplitude of the output current,it does not generate harmonics/***,it has a negligible adverse effect on power *** is finally concluded that the performance of the sliding mode-based IDM is reliable from the standpoints of islanding detection and power quality.

关键词： Islanding detection method(IDM) power quality sliding mode controller total harmonic distortion(THD) voltage positive feedback(VPF)

Conduction Band-Edge Non-Parabolicity Effects on Impurity states in(In,Ga)N/GaN Cylindrical QWWs

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Communications in Theoretical Physics 2014年第2期61卷 253-256页

作者： Haddou El ghazi Anouar Jorio LPs Faculty of Science Dhar EL MehrezBP 1796 Fes-Atlas Morocco special Mathematics CPGE My YoussefRabat Morocco

In this paper, the conduction band-edge non-parabolicity(NP) and the circular cross-section radius effects on hydrogenic shallow-donor impurity ground-state binding energy in zinc-blende(ZB) InGaN/GaN cylindrical QWWs are reported. The finite potential barrier between(In,Ga)N well and GaN environment is considered. Two models of the conduction band-edge non-parabolicity are taking into account. The variational approach is used within the framework of single band effective-mass approximation with one-parametric 1s-hydrogenic trial wave-function. It is found that NP effect is more pronounced in the wire of radius equal to effective Bohr radius than in large and narrow wires. Moreover,the binding energy peak shifts to narrow wire under NP effect. A good agreement is shown compared to the findings results.

关键词：施主杂质氮化镓物性导带圆柱 Ga 玻尔半径氮化铟镓