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发育迟滞的一种少见病因:迟发性的原发性胃出口阻塞

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世界核心医学期刊文摘（儿科学分册） 2006年第1期2卷 34-34页

作者： nazir z. Arshad M. 贺文龙 Section of Pediatric Surgery Department of Surg ery Aga Khan University Hospital Karachi 74800 Pakistan

We describe our experience of 2 children and review 6 previously reported case s of late-onset primary gastric outlet obstruction. The patients presented with abdominal pain, recurrent nonbilious vomiting, and growth retardation after a v ariable period of normal food intake. There was no history of peptic ulceration and corrosive ingestion. Barium meal showed dilated stomach with delayed gastric emptying. Exploration demonstrated dilated stomach with no intrinsic or extrins ic mechanical obstruction at the pylorus. Heineke-Mikulicz.pyloroplasty was cur ative. Patients improved postoperatively and started thriving. We propose etiolo gy and the term pyloric achalasia for this late-onset functional gastric outlet obstruction.

关键词：少见病因胃膨胀患儿症状胆汁性呕吐消化性溃疡胃排空延迟钡餐检查正常进食机械性阻塞外源

Optimiz.tion Based on Convergence Velocity and Reliability for Hydraulic Servo System

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Chinese Journal of Aeronautics 2009年第4期22卷 407-412页

作者： Muhammad Babar nazir School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics

This article presents an optimal hybrid fuz.y proportion integral derivative （HFPID） controller based on combination of proportion integral derivative （PID） and fuz.y controllers, by which the parameters could be evaluated by global optimiz.tion either in convergence velocity or in convergence reliability. Focusing on the nonlinear factors of hydraulic servo system, this article takes advantage of PID and fuz.y logic controller integrated with scaling factors to acquire precise tracking performances. To further improve the performances, it provides new developed optimiz.tion with rapid convergence to attain reliable approach probability. Focusing on the performance indictors of evolutionary algorithm, this article presents a new technique to predict reliability of the optimiz.tion algorithm. Statistics authenticates the effectiveness and robustness of the optimiz.tion. Further, many simulation and experimental results indicate that the optimal HFPID could acquire perfect immunity against parametric uncertainties with external disturbance.

关键词： adaptive control system novel evolutionary algorithm hydraulic control equipment convergence velocity convergencereliability optimiz.tion

Weighted ebyev-Ostrowski type inequalities

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Applied Mathematics and Mechanics(English Edition) 2007年第7期28卷 901-906页

作者： Arif Rafiq nazir Ahmad Mir Farooq Ahmad Mathematics Department COMSATS Institute of Information TechnologyIslamabad 44000Pakistan Centre for Advanced Studies in Pure and Applied Mathematics Bahanddin Zakariya UniversityMultan 60800Pakistan

In account of the famous Cebysev inequality, a rich theory has appeared in the literature. We establish some new weighted Cebysev type integral inequalities. Our proofs are of independent interest and provide new esti... 详细信息

关键词： Cebysev type inequalities L∞ (a b) spaces absolutely continuous functions weight functions

A one-step,tunable method of selective reactive sputter deposition as a wrinkling approach for silver/polydimethylsiloxane for electrically conductive pliable surfaces

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Microsystems & Nanoengineering 2022年第4期8卷 221-231页

作者： Joel Y.Y.Loh Ali z.ineddine Moein Shayegannia Robyn McNeil Liam McRae nazir P.Kherani Department of Electrical and Computing Engineering University of TorontoTorontoON M5S 3G4Canada Department of Material Science and Engineering University of TorontoTorontoON M5S 3E4Canada

The wrinkle period and morphology of a metal thin film on an elastic substrate is typically controlled by modifying the substrate before carrying out additional metal deposition ***,we show that a simultaneously selective and reactive sputtering plasma that modifies the surface of a polydimethylsiloxane(PDMS)substrate while not reacting with the metal during the deposition process decreases the wrinkle wavelength and induces additional wrinkling components and features such as ripples or *** selective reaction of the nitrogen plasma with PDMS functionaliz.s the siloxane surface into silicon *** hardens the immediate surface of PDMS,with a quadratic increase in the Young’s modulus as a function of the sputtering flow *** increase in the critical strain mismatch and the corresponding presence of folds in the nitrogen-modified wrinkled silver film form a suitable plasmonic platform for surface-enhanced Raman spectroscopy(SERS),yielding an enhancement factor of 4.8×105 for detecting *** enhancement is linked to the emergence of electromagnetic hotspots from surface plasmon polariton coupling between the folds/wrinkles,which in turn enables the detection of low concentrations of organics using ***,when strained,the nitrogen-modified wrinkles enhance electrical conductivity by a factor of 12 compared with unmodified ***,the optical properties of the substrate can be tuned by altering the N2 *** simple addition of nonreactive nitrogen to silver sputtering enables simultaneous PDMS hardening and growth of the silver film and together provide a new avenue for tuning wrinkling parameters and enhancing the electrical conductivity of pliable surfaces.

关键词： silver reactive film

Photocatalysis vs adsorption by metal oxide nanoparticles

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Journal of Materials Science & Technology 2022年第36期131卷 122-166页

作者： Usman Qumar Jahan z.b Hassan Rukhsar Ahmad Bhatti Ali Raz. Ghaz.nfar nazir Walid Nabgan Muhammad Ikram Solar Cell Applications Research Lab Department of PhysicsGovernment College University Lahore54000 PunjabPakistan Department of Physics University of Lahore(Chenab Campus)Adjacent Chenab BridgeGujrat50700 PunjabPakistan Department of Physics University of Sialkot(USKT)1-Km Main Daska RoadSialkot51040 PunjabPakistan Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 05006Republic of Korea Departament d’Enginyeria Química Universitat Rovira i VirgiliAv Països Catalans 2643007 TarragonaSpain.

Background:Metal oxide(MO)nanomaterials and related nanocomposites have been extensively studied for their potential use in water *** of their controlled morphologies,texture qualities,variable surface chemistry,distinct crystalline nature,high stability,and tunable band edges,MO nanostructured materials are highly selective towards deleting organic contaminants and heavy metal ions via adsorption and semiconductor ***-enhanced photocatalysis has recently received increasing interest,mainly due to the ability of the metal to directly or indirectly degrade pollutants.A diverse selection of MOs,with titanium dioxide(Ti O2),z.nc oxide(z. O),iron oxides(IO),and tungsten(W),as well as graphene-MOs nanocomposites with variable structure,crystalline,and morphological properties,offers a powerful platform for the growth of effective ***:The current work discusses novel advancements and potential for the removal of adsorptive and photocatalytic degradation of organic compounds(phenolic,pesticide molecules,dyes,and so on)as well as heavy metal ions using semiconductor materials.A photocatalyst based on a MO-scheme heterostructure can manage the appropriate conduction band(CB)and valence band(VB)locations,securing considerable redox *** review should be of interest to the broad readership dealing with applied and fundamental aspects of water treatments and material *** strategies including surface modification,plasmonic enhancement,and metal cocatalysts have been introduced to enhance photocatalytic *** findings:The current article discussed the significantly utiliz.d synthesis strategies and mechanism of heterojunction photocatalysts using a ***,adsorption sections guarantee that mercury,chromium,cadmium,arsenic,and lead-based ions are successfully removed from polluted water via the adsorption *** characteristics,such as concentration,coexisting ions,p H,and ki

关键词： Photocatalyst Adsorbate Metal Oxides z.scheme Surface Modification Heterojunction Semiconductor heterostructures Nanoparticles

LR(K) Parser Construction Using Bottom-up Formal Analysis

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Journal of Software Engineering and Applications 2012年第1期5卷 21-28页

作者： nazir Ahmad z.far 不详

Design and construction of an error-free compiler is a difficult and challenging process. The main functionality of a compiler is to translate a source code to an executable machine code correctly and efficiently. In formal verification of software, semantics of a language has more meanings than the syntax. It means source program verification does not give guarantee the generated code is correct. This is because the compiler may lead to an incorrect target program due to bugs in itself. It means verification of a compiler is much more important than verification of a source program. In this paper, we present a new approach by linking context-free grammar and z.notation to construct LR(K) parser. This has several advantages because correctness of the compiler depends on describing rules that must be written in formal languages. First, we have defined grammar then language derivation procedure is given using right-most derivations. Verification of a given language is done by recursive procedures based on the words. Ambiguity of a language is checked and verified. The specification is analyz.d and validated using z.Eves tool. Formal proofs are presented using powerful techniques of reduction and rewriting available in z.Eves.

关键词： Compiler Construction LR(K) Parser Context-Free Grammar z Specification Correctness Verification

Breaking the symmetry of colloidal 2D nanoplatelets:Twist induced quantum coupling

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Nano Research 2023年第7期16卷 10522-10529页

作者： z.hid nazir Yingz.uo Lun Jialu Li Gaoling Yang Mingrui Liu Shuqi Li Gang Tang Guofeng z.ang Jiawang Hong Liantuan Xiao Haiz.eng z.ong MIIT Key Laboratory for Low-dimensional Quantum Structure and Devices School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China MIIT Key Laboratory for Low-dimensional Quantum Structure and Devices School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyCollaborative Innovation Center of Extreme OpticsShanxi UniversityTaiyuan 030006China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China

Twist provides a new degree of freedom for nanomaterial modifications,which can provide novel physical ***,colloidal two-dimensional(2D)twisted CdSe nanoplatelets(NPLs)are successfully fabricated and their morphology can change from totally flat to edge-twisted,and then to middle-twisted with prolonged reaction *** combining experiments and corresponding theoretical analyses,we have established the length-dependent relationships between the surface energy and twist,with a critical lateral dimension of 30 *** found that the defects formed during the synthesis process play a vital role in generating intense stress that develops a strong torsion tensor around the edges,resulting in edge-twisted and final middletwisted ***,due to the geometric asymmetry of twisted NPLs,the dissymmetry factor of single particle NPLs can reach up to ***,quantum coupling occurs in middle-twisted NPLs by twisting one parent NPL into two daughter NPLs,which are structurally and electronically *** work not only further deepens our understanding of the twist mechanism of 2D NPLs during colloidal synthesis,but also opens a pathway for applications using twistronics and quantum technology.

关键词： nanoplatelets CdSe twist circular dichroism quantum coupling

Model Analysis of Equivalence Classes in UML Events Relations

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Journal of Software Engineering and Applications 2013年第12期6卷 653-661页

作者： nazir Ahmad z.far Department of Computer Science King Faisal University Hofuf KSA

Unified Modeling Language (UML) has become a de facto standard for design, specification and modeling of object oriented software systems. UML structures being graphical in nature lack defining semantics of the systems and are prone to causing errors. Formal methods are proved to be a powerful tool for requirement analysis, design and specification of software systems. Hence, linking UML with formal approaches will enhance modeling power of software systems. In this paper, an approach is developed by integrating UML and z.notation focusing on equivalence relation of the state diagrams. The z.is used because it is based on the first order predicate logic having rigorous computer tool support. The reflexivity, symmetry and transitivity properties, being important at design level, are identified and described. It is believed that this approach will be effective and useful at both academics and industrial level. The need, reasoning and benefits of the integrated approach are discussed. The resultant formal models are analyz.d and validated using z.Eves tool.

关键词： UML State Diagrams Equivalence Relations Formal Methods z notation Validation and Verification

Syntax-Tree Regular Expression Based DFA FormalConstruction

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Intelligent Information Management 2012年第4期4卷 138-146页

作者： nazir Ahmad z.far Fawaz.Alsaade Department of Computer Science King Faisal University Hofuf KSA

Compiler is a program whose functionality is to translate a computer program written in source language into an equivalent machine code. Compiler construction is an advanced research area because of its siz. and complexity. The source codes are in higher level languages which are usually complex and, consequently, increase the level of abstraction. Due to such reasons, design and construction of error free compiler is a challenge of the twenty first century. Verification of a source program does not guarantee about correctness of code generated because the bugs in compiler may lead to an incorrect target program. Therefore, verification of compiler is more important than verifying the source programs. Lexical analyz.r is a main phase of compiler used for scanning input and grouping into sequence of tokens. In this paper, formal construction of deterministic finite automata (DFA) based on regular expression is presented as a part of lexical analyz.r. At first, syntax tree is described based on the augmented regular expression. Then formal description of important operators, checking nullability and computing first and last positions of internal nodes of the tree is described. In next, the transition diagram is described from the follow positions and converted into deterministic finite automata by defining a relationship among syntax tree, transition diagram and DFA. Formal specification of the procedure is described using z.notation and model analysis is provided using z.Eves toolset.

关键词： Automata Theory Compiler Verification Lexical Analyz.r Automated Tools z Specification