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Control of Wave Propagation and Effect of Kerr Nonlinearity on Group Index

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Communications in Theoretical Physics 2013年第7期60卷 87-92页

作者： Hazrat ali Ziauddin Iftikhar ahmed Department of Physics University of Malakand Department of Physics COMSATS Institute of Information Technology

We use four-level atomic system and control the wave propagation via forbidden decay rate. The Raman gain process becomes dominant on electromagnetically induced transparency (EIT) medium by increasing the forbidden decay rate via increasing the number of atoms [G.S. Agarwal and T.N. Dey, Phys. Rev. A 74 (2005) 043805 and K. Harada, T. Kanbashi, and M. Mitsunaga, Phys. Rev. A 73 (2006) 013803]. The behavior of wave propagation is dramatically changed from normal (subluminal) to anomalous (superluminal) dispersion by increasing the forbidden decay rate. The system can also give a control over the group velocity of the light propagating through the medium via Kerr field.

关键词： normal and anomalous dispersion Kerr field group index

Comprehensive evaluation and sensitivity analysis of regeneration energy for acid gas removal plant using single and activated-methyl diethanolamine solvents

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1684-1693页

作者： Ammar ali Abd Samah Zaki Naji ahmed Barifcani Water Resources Engineering College Al-Qasim Green UniversityBabylonIraq Petroleum Engineering Department Kerbala UniversityKerbalaIraq Chemical Engineering Department Curtin University of TechnologyPerthAustralia.

The absorption of acid gas using reactive amines is among the most widely used types of capturing ***,the absorption process requires intensive energy expenditure majorly in the solvent regeneration *** study simultaneously evaluated the regeneration energy of MDEA and PZ/MDEA solvents in terms of heat of absorption,sensible heat,and vaporization *** Hysys version 8.8 simulation tool is applied to model the full acid gas removal plant for the chemical absorption *** new energy balance technique presents around the absorption and desorption columns to bring a new perspective of energy distribution in the capturing of acid gas *** analysis of regeneration energy and its three contributors is performed at several operation parameters such as absorber and stripper pressures,lean amine circulation rate,solvent concentration,reflux ratio,and CO2 and H2 S *** results show that the heat of absorption of PZ/MDEA system is higher than that for MDEA system for the same operating *** sensible heat is the main contributor in the required regeneration energy of MDEA solvent *** simulation results have been validated against data taken from real plant and *** product specifications of our simulation corroborate with real plant data in an excellent approach;additionally,the profile temperature of the absorber and the stripper columns are in good agreement with *** overall results highlight the direction of the effects of each parameter on the heat of absorption,sensible heat,and vaporization heat.

关键词： Heat of absorption Sensible heat Vaporization heat Regeneration energy Acid gases capturing Piperazine Activated-Methyl diethanolamine

Evaluation of the Neurodevelopmental Outcome of Toddlers with Spinal Dysraphism after Surgical Repair Using ASQ-3™ Scores

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Anti-wear properties evaluation of frictional sliding interfaces in automobile engines lubricated by copper/graphene nanolubricants

Open Journal of Modern Neurosurgery（现代神经外科学进展） 2024年第1期

作者： Mujahid Imam Fawaz Eljili Marhoom Sawsan Aldeaf ali awad ahmed Zidan Mohamed Mustafa ahmed Sanna Taha

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Friction 2020年第5期8卷 905-916页

作者： Mohamed Kamal ahmed ali Xianjun HOU Mohamed AAABDELKAREEM Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Automotive and Tractors Engineering Department Faculty of EngineeringMinia UniversityEl-Minia 61111Egypt Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China

Owing to the significance of improving fuel economy, reducing emissions, and extending the durability of engine components, this study focused on the tribological performance of nano-additives. In this study, copper (Cu) and graphene (Gr) nanomaterials were dispersed in a fully formulated engine oil (5W-30) with different concentrations. The tribological trials were investigated under various speeds and loads, utilizing a reciprocating tribometer to mimic the ring/liner interfaces in the engine. The frictional surface morphologies were com-prehensively analyzed using electron probe X-ray microanalysis (EPMA), field emission scanning electron microscopy (FESEM), energy dispersive spectrometer (EDS), and three dimensional (3D) surface profilometry to explore the mechanisms responsible for improving the tribological performance of the frictional sliding parts in the engine. The tribological test results illustrated that lubrication by nano-additives reduced the wear rate (WR) and friction coefficient (COF) by 25%–30% and 26.5%–32.6%, respectively, as compared with 5W-30. The results showed that this is a promising approach for increasing the durability and lifespan of frictional sliding components and fuel economy in automobile engines.

关键词： engine tribology nanomaterial nanolubricant friction wear tribofilm

Quantification of Urban Sprawl for Past-To-Future in Abha City,Saudi Arabia

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Computer Modeling in Engineering & Sciences 2021年第11期129卷 755-786页

作者： Saeed AlQadhi Javed Mallick Swapan Talukdar ahmed ali Bindajam ahmed ali A.Shohan Shahfahad Department of Civil Engineering College of EngineeringKing Khalid UniversityAbha61411Saudi Arabia Department of Geography University of Gour BangaMalda732103India Department of Architecture and Planning College of EngineeringKing Khalid UniversityAbha61411Saudi Arabia Department of Geography Faculty of Natural SciencesJamia Millia IslamiaNew Delhi110025India

Given that many cities in Saudi Arabia have been observing rapid urbanization since the 1990s,scarce studies on the spatial pattern of urban expansion in Saudi Arabia have been ***,the present study investigates the evidence of land use and land cover(LULC)dynamics and urban sprawl in Abha City of Saudi Arabia,which has been experiencing rapid urbanization,from the past to the future using novel and sophisticated *** SVM classifier was used in this study to classify the LULC maps for 1990,2000,and *** LULC dynamics between 1990–2000,2000–2018,and 1990–2018 have been analyzed using delta()change and the Markovian transitional probability *** sprawl or urban expansion was modeled using two approaches,such as landscape fragmentation and presence frequency for the first *** future LULC map for 2028 was predicted using the artificial neural network-cellular automata model(ANN-CA).Future LULC was analyzed using landscape fragmentation and frequency *** results of LULC maps showed that urban areas increased by 334.4%between 1990 and *** Delta change rate showed that 16.34%in urban areas has increased since ***,the transitional probability matrix between 1990 and 2018 reported that the built-up area is the largest stable LULC,having an 83.6%transitional probability *** 17.9%,21.8%,12.4%,and 10.5%of agricultural land,scrubland,exposed rocks,and water bodies were transformed into built-up *** sprawl models showed that 139 km^(2)of new urban areas had been set up in 2018,49 and 69 km^(2)in 1990 and ***,in 2018,more than 200%of urban areas were stabilized or became core urban *** future LULC map(2028)showed that the built-up area would be 343.72 km^(2),followed by scrubland(342.98 km^(2))and sparse vegetation(89.96 km^(2)).The new urban area in 2028 would be 169 km^(2).The authorities and planners should focus more on the sustainable development of urban areas;otherwise,it would

关键词： Urban sprawl LULC landscape fragmentation cellular automata SVM frequency approach

Ding w-Flat Modules and Dimensions

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Algebra Colloquium 2018年第2期25卷 203-216页

作者： Fuad ali ahmed Almahdi Mohammed Tamekkante Department of Mathematics Faculty of Sciences King Khalid University P. O. Box. 9004 Abha Saudi Arabia Laboratory MACS Faculty of Sciences University Moulay Ismail 5000 P.B. 11201 Zitoune Meknes Morocco

The introduction of w-operation in the class of flat modules has been successful. Let R be a ring. An R-module M is called a w-fiat module if Tor1r（M, N） is GV-torsion for all R-modules N. In this paper, we introduce the w-operation in Gorenstein homological algebra. An R-module M is called Ding w-flat if there exists an exact sequence of projective R-modules ... → P1 → P0 → p0 → p1 → ... such that M Im（P0 → p0） and such that the functor HomR （-,F） leaves the sequence exact whenever F is w-flat. Several well- known classes of rings are characterized in terms of Ding w-flat modules. Some examples are given to show that Ding w-flat modules lie strictly between projective modules and Gorenstein projective modules. The Ding w-flat dimension （of modules and rings） and the existence of Ding w-flat precovers are also studied.

关键词： w-fiat module and dimension Gorenstein projective module and dimension,strongly Gorenstein flat module

Multi-Objective Vendor Selection Problem of Supply Chain Management Under Fuzzy Environment

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Journal of the Operations Research Society of China 2021年第1期9卷 33-62页

作者： Srikant Gupta Irfan ali Aquil ahmed Department of Statistics and Operations Research Aligarh Muslim UniversityAligarhUPIndia

Survival of a company in today's competitive business environment depends mainly on its supply *** adequate supply chain gives a competitive edge to a ***,which is the initial stage of a supply chain,can be made efficient by making an appropriate selection of *** vendor selection results not only in reduced purchasing costs,decreased production lead time,increased customer satisfaction but also in improved corporate *** general,the vendor selection problem is a multi-objective decision-making problem that involves some quantitative and qualitative ***,we have considered a multi-objective ven-dor selection problem(MOV SP)with three multiple objective goals:minimization of net ordering price,minimization of rejected units and minimization of late delivered *** most of the cases,information about the price of a unit,percentage of rejected units,percentage of late delivered units,vendor rating value and vendor quota flexibil-ity may not be known precisely due to some *** this paper,imprecision in input information is handled by the concept of a simulation technique,where the parameter follows the uniform ***,stochastic,a-cut and ranking function approaches are used to get the crisp value of the simulated data *** four differ-ent algorithms,namely-fuzzy programming,goal programming,lexicographic goal programming and D1-distance algorithm,have been used for solving the *** last,three different types of simulated data sets have been used to illustrate the work.

关键词： Vendor selection problem Trapezoidal fuzzy number α-Cut and ranking function Fuzzy programming Goal programming Lexicographic goal programming

The Research And Development of Sunlite Yarn Fabric Used as Thermal Underwear And The Study of Its Wear Performance

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The Research And Development of Sunlite Yarn Fabric Used as ...

作者： ahmed awad ABDELMaliK ABDELTAM 东华大学

学位级别：硕士

There is an amount of fibers used for thermal fabrics in textile market nowadays, such as wool, kapok and some types of synthetic fibers. A polydihydricals alcohol terephthalate, its trademark is Sunlite, was introduced into the market. It has a hollow space in the center of the fiber. In this paper, it was studied to see if its properties meet the criteria of warm underwear. Two types of yarn number SunLite yarn are used to produce plain stitch fabric with single jersey-knitting machine. Then the fabrics are treated with scoring, dyeing and softening. The fabrics are undergone with an optimal softening plan according to orthogonal design. HDP softener with concentration of 3% shows the best result. After that the properties of the produced fabrics are tested of all the performance required for thermal underwear, including pilling, Thermal resistance, Humidity resistance, Appearance and appearance retention, vertical wicking, Wash and color Fastness, Abrasion Fastness, fiber surface morphology by SEM and Permeability. Then the relevant wear performance of Sunlite fabrics is compared with kapok/cotton blended yarn fabrics. The results showed that. Sunlite fabrics have superior properties of anti-pilling, dimensional stability, wash and abrasion fastness than that of Kapok-cotton blended yarn fabric. While on thermal resistance and humidity resistance, vertical wicking, Sunlite fabrics showed inferior performance than that of kapok/cotton blended yarn fabric.

关键词： SunLite fiber knitted fabric orthogonal design wear performance warm underwear

Fingerprint matching,spoof and liveness detection:classification and literature review

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Frontiers of Computer Science 2021年第1期15卷 179-196页

作者： Syed Farooq ali Muhammad Aamir KHAN ahmed Sohail ASLAM Department of Software Engineering University of Management and TechnologyLahore 54770Pakistan Department of Informatics and Systems University of Management and TechnologyLahore 54770Pakistan Department of Computer Science University of Management and TechnologyLahore 54770Pakistan

Fingerprint matching,spoof mitigation and liveness detection are the trendiest biometric techniques,mostly because of their stability through life,uniqueness and their least risk of *** recent decade,several techniques are presented to address these challenges over well-known *** study provides a comprehensive review on the fingerprint algorithms and techniques which have been published in the last few *** divides the research on fingerprint into nine different approaches including feature based,fuzzy logic,holistic,image enhancement,latent,conventional machine learning,deep learning,template matching and miscellaneous *** these,deep learning approach has outperformed other approaches and gained significant attention for future *** reviewing fingerprint literature,it is historically divided into four eras based on 106 referred papers and their cumulative citations.

关键词： computer society template matching fingerprint recognition survey deep learning machine learning