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Inhomogeneous lens antenna design with fan-beam radiation pattern

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Chinese Optics Letters 2016年第12期14卷 89-93页

作者： mohammad Mahdi Taskhiri mohammad khalaj-amirhosseini School of Electrical Engineering Iran University of Science and Technology

This Letter presents an original technique to design and synthesize an inhomogeneous asymmetrical lens resulting in a special fan-beam radiation pattern in a wide frequency bandwidth. The vertical and horizontal planes of the fan-beam radiation pattern can be determined separately. Wide angle search and detection are achievable by using this type of lens antenna because of its suitable radiation pattern. The proposed relative index profile is validated by the means of commercial CST software and an FDTD scheme.

关键词： antenna inhomogeneous asymmetrical bandwidth validated separately wavefront elliptical matching crossed

Inhomogeneous Perforated Reflect-Array Antennas

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Wireless Engineering and Technology 2011年第2期2卷 80-86页

作者： Mojtaba Moeini-Fard mohammad khalaj-amirhosseini Department of Electrical Engineering Iran University of Science and Technology

A new reflect-array antenna structure is proposed. This structure utilizes a perforated substrate as a reflecting surface with the lattice of different holes. The effective electric permittivity of the dielectric substrate is altered by drilling holes with different diameter and spacing, which provide an in-homogeneous dielectric layer. This in-homogeneous dielectric layer can be controlled by these holes to collimate the reflected waves in the special direction. Absence of resonator elements in this structure will reduce the dielectric and conductor losses, which are the main losses in reflect-array antennas at resonance frequency. In addition, a simple method based on an equivalent circuit model is introduced for designing and analyzing this kind of antennas. Using this method, the suitable values of the diameter and spacing of the holes at each point on the reflecting surface are obtained. Some proposed antennas are designed at millimeter wave frequency and simulated by full-wave analyzer;CST Microwave Studio software to verify theoretical results.

关键词： Perforated Substrate Reflect-Array Antenna

A Closed Form Solution For Longitudinally Inhomogeneous Waveguides

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A Closed Form Solution For Longitudinally Inhomogeneous Wave...

2009 3rd IEEE International Symposium on Microwave,Antenna,Propagation and EMC Technologies for Wireless Communications

作者： mohammad khalaj-amirhosseini College of Electrical Engineering-Iran University of Science and Technology Tehran -Iran

A closed form analytic solution is introduced for arbitrary Longitudinally Inhomogeneous Waveguides （LIWs）. First, the differential equations of LIWs are written as a suitable matrix differential equation. Then, the matrix differential equation is solved to obtain the chain parameter matrix of LIWs. Afterward, the electric and magnetic fields at any point and also the scattering parameters are obtained using the chain parameter matrix. The validation of the introduced solution is studied, finally.

关键词： Longitudinally Inhomogeneous Waveguides Closed Form Analytic Solution Matrix Differential Equations.

Analysis of Nonuniform Transmission Lines Through Analysis of Their Periodic Model

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Analysis of Nonuniform Transmission Lines Through Analysis o...

2006 7th International Symposium on Antennas, Propagation and EM Theory

作者： mohammad khalaj-amirhosseini College of Electrical Engineering-Iran University of Science and Technology

A novel method is introduced for frequency domain analysis of arbitrary nonuniform transmission lines (NTLs).A periodic NTL is made from cascading infinite number of desired NTL with each ***,the ABCD parameters of de... 详细信息

关键词： Fourier Analysis of Nonuniform Transmission Lines Through Analysis of Their Periodic Model

OPTIMUM DESIGN OF S-G-S AND S-O-S INTERCONNECTS USING LEAST MEAN SQUARE METHOD

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OPTIMUM DESIGN OF S-G-S AND S-O-S INTERCONNECTS USING LEAST ...

IEEE 2005 International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications

作者： Habib Ghorbaninezhad-Foumani mohammad khalaj-amirhosseini College of Electrical Engineering Iran University of Science and Technology Tehran I. R. Iran College of Electrical Engineering Iran University of Science and Technology Tehran I. R. Iran

Two new interconnects structure called S-G-S (Signal-Ground-Singal) and S-O-S (Signal-Opened-Signal) interconnects are proposed and a method is presented to optimum desine of them. A frequency domain

关键词： OPTIMUM DESIGN OF S-G-S AND S-O-S INTERCONNECTS USING LEAST MEAN SQUARE METHOD

COPLANAR TRANSMISSION LINE EXPOSED TO ELECTROMAGNETIC FIELD

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COPLANAR TRANSMISSION LINE EXPOSED TO ELECTROMAGNETIC FIELD

IEEE 2005 International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications

作者： Ahmad Cheldavi mohammad khalaj-amirhosseini Shima Abbasi College of Electrical Engineering Iran University of Science and Technology Narmak Tehran I.R. IRAN College of Electrical Engineering Iran University of Science and Technology Narmak Tehran I.R. IRAN College of Electrical Engineering Iran University of Science and Technology Narmak Tehran I.R. IRAN

The concept of this paper is to find the voltages and currents induced by externall plane waves on a coplanar transmission line. This three dimensional problem is subdivided into two simple problems:

关键词： COPLANAR TRANSMISSION LINE EXPOSED TO ELECTROMAGNETIC FIELD

Boron Nitride-Integrated Lithium Batteries: Exploring Innovations in Longevity and Performance

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 13-40页

作者： Angizi, Shayan Alem, Sayed Ali Ahmad Torabian, Mahdi khalaj, Maryam Golberg, Dmitri Pakdel, Amir McMaster Univ Dept Chem Engn 1280 Main St W Hamilton ON L8S 4L7 Canada Montan Univ Leoben Inst Chem Polymer Mat Otto Glockel Str 2 A-8700 Leoben Austria Politecn Milan Dept Chem Mat & Chem Engn Piazza Leonardo Vinci 32 I-20133 Milan Italy Northwestern Univ Dept Mat Sci & Engn Evanston IL 60208 USA Queensland Univ Technol QUT Ctr Mat Sci 2 George Brisbane Qld 4000 Australia Queensland Univ Technol QUT Sch Chem & Phys 2 George Brisbane Qld 4000 Australia Natl Inst Mat Sci NIMS Res Ctr Mat Nanoarchitecton MANA Namiki 1 Ibaraki 3050044 Japan Univ Dublin Trinity Coll Dublin Dept Mech Mfg & Biomed Engn Dublin D02PN40 Ireland

The current global warming, coupled with the growing demand for energy in our daily lives, necessitates the development of more efficient and reliable energy storage devices. Lithium batteries (LBs) are at the forefront of emerging power sources addressing these challenges. Recent studies have shown that integrating hexagonal boron nitride (h-BN) nanomaterials into LBs enhances the safety, longevity, and electrochemical performance of all LB components, including electrodes, electrolytes, and separators, thereby suggesting their potential value in advancing eco-friendly energy solutions. This review provides an overview of the most recent applications of h-BN nanomaterials in LBs. It begins with an informative introduction to h-BN nanomaterials and their relevant properties in the context of LB applications. Subsequently, it addresses the challenges posed by h-BN and discusses existing strategies to overcome these limitations, offering valuable insights into the potential of BN nanomaterials. The review then proceeds to outline the functions of h-BN in LB components, emphasizing the molecular-level mechanisms responsible for performance improvements. Finally, the review concludes by presenting the current challenges and prospects of integrating h-BN nanomaterials into battery research. Integrating h-BN into lithium batteries enhances safety, longevity, and mechanical integrity of battery components by mitigating dendritic growth and side reactions. Its high ionic and thermal conductivities improve lithium transference and heat management, enhancing performance and reliability. image

关键词： electrode electrolyte hexagonal boron nitride lithium battery separator METAL BATTERIES H-BN ION BATTERIES 2-DIMENSIONAL MATERIALS POLYMER ELECTROLYTE HIGH-TEMPERATURE ANODES NANOSHEETS DENDRITE FUNCTIONALIZATION

Auto-tuning PVT data using multi-objective optimization: Application of NSGA-Ⅱ algorithm

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Petroleum 2024年第1期10卷 135-149页

作者： Abdolhadi Zarifi mohammad Madani mohammad Jafarzadegan Reservoir Engineering Systems Petroleum Engineering Department Main Office Building of National Iranian South Oil Company (NISOC) Combined Planning Management National Iranian Oil Company (NIOC) Reservoir Engineering Division Petroleum Engineering Department Petroleum Engineering and Development Company (PEDEC)

Reservoir simulation is known as perhaps the most widely used, accurate, and reliable method for field development in the petroleum industry. An integral part of a reliable reservoir simulation process is to consider robust and rigorous tuned EOS models. Traditionally, EOS models are tuned iteratively through arduous workflows against experimental PVT data. However, this comes with a number of drawbacks such as forcingly using weight factors, which upon alteration adversely affects the optimization *** objective of the current work is thus to introduce an auto-tune PVT matching tool using NSGA-II multi-objective optimization. In order to illustrate the robustness of the presented technique, three different PVT samples are used, including two black-oil and one gas condensate sample. We utilize PengRobinson EOS during all the manual and auto-tuning processes. Comparison of auto-tuned EOS-generated results with those of experimental and computed statistical error values for these samples clearly show that the proposed method is robust. In addition, the proposed method, contrary to the manual matching process, provides the engineer with several matched solutions, which allows them to select a match based on the engineering background to be best amenable to the problem at hand. In addition, the proposed technique is fast, and can output several solutions within less time compared to the traditional manual matching method.

关键词： Auto-tuning PVT Equation of state NSGA-II Multi-objective optimization

Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad M.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SFP was compared to HMA in terms of engineering characteristics and *** to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HMA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt