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Chinese Physics Letters 2016年第1期33卷 132-135页

作者： md.ghulam saber Rakibul Hasan Sagor md.Ruhul Amin Department of Electrical and Electronic Engineering Islamic University of Technology

The linear dispersion relation of a trapezoidally corrugated slow wave structure （TCSWS） is analyzed and presented. The size parameters of the TCSWS are chosen in such a way that they operate in the x-band frequency range. The dispersion relation is solved by utilizing the Rayleigh-Fourier method by expressing the radial function in terms of the Fourier series. A highly accurate synthetic technique is also applied to determine the complete dispersion characteristics from experimentally measured resonances （cold test）. Periodic structures resonate at specific frequencies when the terminals are shorted numerical calculation, synthetic technique and cold appropriately. The dispersion characteristics obtained from test are compared, and an excellent agreement is achieved.

关键词： of on A Comparative Study of Dispersion Characteristics Determination of a Trapezoidally Corrugated Slow Wave Structure Using Different Techniques in been is

Extraction of optimized parameters for Si_(0.6)Ge_(0.4)material and SPP mode propagation through Si_(0.6)Ge_(0.4)/Ag/Si_(0.6)Ge_(0.4)waveguide

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Optoelectronics Letters 2013年第6期9卷 454-457页

作者： md.ghulam saber Rakibul Hasan Sagor Department of Electrical and Electronic Engineering Islamic University of Technology

The Lorentz model and modified Debye model(mdM)parameters for Si0.6Ge0.4are presented.A nonlinear optimization algorithm is *** obtained parameters are used to determine the complex relative permittivity of Si0.6Ge0.4,and compared with the experimental data for *** the obtained parameters are used to analyze the properties of symmetric surface plasmon polariton(SPP)mode propagation in a dielectric-metal-dielectric(Dmd)material constructed with silver(Ag)and Si0.6Ge0.4for further verifying the extracted parameters.

关键词： SPP模式优化参数材料提取传播波导相对介电常数表面等离激元

Propagation of Surface Plasmon Polariton in the Single Interface of Gallium Lanthanum Sulfide and Silver

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Photonic Sensors 2014年第1期4卷 58-62页

作者： Rakibul Hasan Sagor md.ghulam saber md.Ruhul Amin Department of Electrical and Electronic Engineering Islamic University of TechnologyBoard BazarGazipur1704Bangladesh

The propagation characteristics of the surface-plasmon-polariton （SPP） mode in the single interface of silver （Ag） and gallium lanthanum sulfide （GLS） have been studied both analytically and numerically. The obtained numerical results show an excellent agreement with the analytical ones. The locations of the spatial resonance point along the direction of propagation were determined for the dielectric and the metal.

关键词： Surface-plasmon-polariton gallium lanthanum sulfide glass-metal interface

Horizontal borehole azimuth optimization for enhanced stability and coal seam gas production

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Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第1期3卷 115-126页

作者： Erfan saber Qingdong Qu Saiied MAminossadati Yiran Zhu Zhongwei Chen School of Mechanical and Mining Engineering The University of QueenslandQueensland4072Australia Commonwealth Scientific and Industrial Research Organization(CSIRO) Mineral ResourcesQCATQueensland4069Australia

Horizontal boreholes have been widely used to extract natural gas from coal ***,these boreholes can encounter severe instability issues leading to production *** drilling azimuth is a potential solution for enhancing borehole stability while considering gas *** this work,we improved and implemented a dual-porosity,fully coupled geomechanical-hydraulic numerical model into COMSOL Multiphysics to investigate into this *** sophisticated numerical model incorporates various critical factors,including desorption-induced matrix shrinkage,stress-dependent anisotropic fracture permeability,and the interactions of gas flow and reservoir deformation in matrices and fractures.A suite of simulation scenarios(e.g.,varying coal strength)was carried out to quantify the impact of drilling azimuth on coal permeability evolution,cumulative gas production,and the borehole break-out width for Goonyella Middle Seam of Bowen Basin,*** model was calibrated against both theoretical permeability values and field gas production *** to the lack of directly measured matrix permeability data,the actual gas production was used to back calculate the best-matched matrix permeability,which is 0.65μD for this particular ***,based on the breakout shape and induced volumetric strains around the borehole,drilling along the maximum horizontal stress does not necessarily lead to the best stability of the borehole,as generally believed.A drilling azimuth between 0and 60results in similar breakout width,whereas a drilling azimuth between 60and 90achieves the most efficient gas *** considering both gas production efficiency and borehole stability,for this particular reservoir condition,the optimum drilling azimuth is determined to be between 45and 60.This study presents a practical approach for determining the optimum drilling azimuth in coal seam gas extraction through in seam boreholes.

关键词： Coal seam gas Borehole stability Gas desorption Directional fracture permeability Borehole break-out

Exploring dielectric phenomena in sulflower-like nanostructures via Monte Carlo technique

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Communications in Theoretical Physics 2024年第4期76卷 188-198页

作者： N saber Z Fadil Hussein Sabbah A Mhirech B Kabouchi L Bahmad Chaitany Jayprakash Raorane Siva Sankar Sana Hassan Fouad Mohamed Hashem Laboratory of Condensed Matter and Interdisciplinary Sciences(LaMCScI) Research Unit Labelled CNRSTURL-CNRST-17.Faculty of SciencesPO Box 1014Mohammed Ⅴ University in RabatMorocco College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait School of Chemical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Applied Medical Science Department Community CollegeKing Saud UniversityPO Box 11433Riyadh Saudi Arabia Department of Dental Health College of Applied Medical SciencesKing Saud UniversityPO Box 12372RiyadhSaudi Arabia

This research focuses on the electric behavior of a mixed ferrielectric sulflower-like *** structure includes a core with spin S_(i)^(Z)-1 atoms and a shell with spin σ_(j)^(Z)-5/2 *** Blume–Capel model and the Monte Carlo technique(MCt)with the Metropolis algorithm are *** are established for absolute zero,investigating stable spin configurations correlated with various physical *** MCt method explores phase transition behavior and electric hysteresis cycles under different physical parameters.

关键词： sulfower-like nanostructure dielectric characteristics Monte Carlo technique phase transition phase diagrams electric hysteresis

Design of a Simple Integrated Coupler for SPP Excitation in a Dielectric Coated Ag Thin Film

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Chinese Physics Letters 2014年第6期31卷 94-97页

作者： Rakibul Hasan Sagor md. Ruhul Amin md. ghulam saber Department of Electrical and Electronic Engineering Islamic University of Technology Board Bazar Gazipur-1704 Bangladesh

A simple integrated coupler is proposed for the efficient excitation of surface plasmon polariton （SPP） mode in a thin metal film. The SPP mode is generated in a single Ag-dielectric interface by the incident field and coupled with an Ag thin film. The coupling efficiency at different wavelengths using two different dielectrics, gallium lanthanum sulfide （GLS） and aluminum gallium arsenide （AIGaAs） is calculated by analyzing the SPP propagation dynamics with the finite difference time domain method. A maximum coupling efficiency of 70~ is obtained at a wavelength of 46Ohm when GLS is used, whereas the corresponding value obtained for A1GaAs is 60~o at 56Onto. The proposed structure can be used to excite SPPs in a nano-thin film from an external bulky source and is easier to fabricate since a single interface metal-dielectric configuration is used to excite the metal-thin film.

关键词： Efficiency

Bio-inspired optimization algorithms for optical parameter extraction of dielectric materials: A comparative study

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Chinese Physics B 2016年第10期25卷 202-208页

作者： md.ghulam saber Kh Arif Shahriar Ashik Ahmed Rakibul Hasan Sagor Department of Electrical and Electronic Engineering Islamic University of Technology (IUT) Department of Electrical and Electronic Engineering Northern University Bangladesh (NUB)

Particle swarm optimization(PSO) and invasive weed optimization(IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired algorithms are used here for the first time in this particular field to the best of our knowledge. The algorithms are used for modeling graphene oxide and the performances of the two are compared. Two objective functions are used for different boundary values. Root mean square(RMS) deviation is determined and compared.

关键词： optical parameter extraction particle swarm optimization invasive weed optimization graphene oxide optimization

质子束放疗在中枢神经系统肿瘤患者中的应用趋势:美国国家癌症数据库分析(2004—2021年)

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国际肿瘤学杂志 2024年第7期51卷 424-431页

作者： saber Amin Chi Lin 美国内布拉斯加大学医学中心放射肿瘤科奥马哈NE 68198

目的评估分析质子束放疗(PBT)在美国中枢神经系统(CNS)肿瘤患者中的使用趋势以及相关影响因素。方法利用美国国家癌症数据库查询2004-2021年CNS肿瘤患者的资料,根据患者的病理组织学类型、确诊年龄、保险状况、家庭收入水平、受教育水... 详细信息

目的评估分析质子束放疗(PBT)在美国中枢神经系统(CNS)肿瘤患者中的使用趋势以及相关影响因素。方法利用美国国家癌症数据库查询2004-2021年CNS肿瘤患者的资料,根据患者的病理组织学类型、确诊年龄、保险状况、家庭收入水平、受教育水平、就诊医院类型等因素,探讨PBT在CNS肿瘤患者中的使用趋势。采用logistic多因素回归分析进行各种因素与PBT使用的相关性分析。结果共纳入192696例CNS肿瘤患者,接受PBT治疗患者为5901例(3.1%),其中年龄≥18岁患者4109例(69.6%)。PBT在CNS肿瘤中的使用率从2004年的1.0%增加到2021年的11.4%。在接受PBT治疗的患者中,胚胎瘤是最常见的儿童肿瘤,而星形细胞瘤是最常见的成人肿瘤。logistic多因素回归分析显示,近年来胶质母细胞瘤、室管膜瘤、髓母细胞瘤、生殖细胞瘤患者采用PBT治疗较星形细胞瘤患者增长更迅速。年龄<18岁、无其他合并症、有私人保险、家庭收入水平较高和近年来确诊也与PBT的使用呈正相关。结论在美国,儿童及青少年患者、无其他合并症、家庭收入水平较高、有私人保险、近年来确诊和特定肿瘤组织学类型的患者更有可能接受PBT治疗。PBT的使用率从2004年的1.0%增加到2021年的11.4%。然而,应接受PBT的患者数量与实际接受PBT的患者数量之间仍存在明显差距。

关键词：质子疗法中枢神经系统肿瘤美国国家癌症数据库

Novel self assembly behavior for γ-alumina nanoparticles

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Particuology 2012年第6期10卷 744-750页

作者： Osama saber Physics Dept Faculty of ScienceKing Faisal UniversityAl-Hassa 31982P.O.Box 400Saudi Arabia Egyptian Petroleum Research Institute Nasr CityP.O.Box 11727CairoEgypt

In this study, self assembly behavior was induced for γ-alumina nanoparticles by adsorption of dimethyl disulfide. Following this trend, we have developed a chemical process to obtain ＇y-alumina in the nano scale. Scanning electron microscopy images of the prepared γ-alumina showed big and strong agglomeration of the nanoparticles indicating that these nanoparticles have strong surface forces. Transmission electron microscopy images confirmed that the γ-alumina nanoparticles 3-7 nm in size were converted to uniform spherical shape in the size range of 1-2 mm after shaking with dimethyl disulfide in the presence of n-hexane at room temperature. This phenomenon did not appear in the case of alumina in the micro scale. The surface properties of the prepared γ-alumina in the nano scale were characterized and compared with the γ-alumina in the micro scale by using low temperature nitrogen adsorption-desorption system, indicating that the specific surface area of the prepared γ-alumina nanoparticles is larger than that of the γ-alumina in the micro scale. Furthermore, micro- and meso-pores were observed for the if-alumina nanoparticles while only mesoporous structure was detected for the γ-alumina in the micro scale. These experimental results suggested that the self assembly behavior of the γ-alumina nanoparticles may be due to the selective adsorption ofdimethyl disulfide in the micropores of these nanoparticles to act as bridge linking the nanoparticles.

关键词： γ-Alumina nanoparticlesNovel self assembly behaviorScanning and transmission electronmicroscopy

Topology optimization and seismic collapse assessment of shape memory alloy(SMA)-braced frames:Effectiveness of Fe-based SMAs

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Frontiers of Structural and Civil Engineering 2022年第3期16卷 281-301页

作者： Aydin HASSANZADEH saber MORADI Department of Civil Engineering Ryerson UniversityToronto M5B 2K3Canada

This paper presents a seismic topology optimization study of steel braced frames with shape memory alloy(SMA)*** SMA-braced frames(SMA-BFs)with either Fe-based SMA or NiTi braces are determined in a performance-based seismic design *** topology optimization is performed on 5-and 10-story SMA-BFs considering the placement,length,and cross-sectional area of SMA bracing ***,strength,and performance-based design constraints are considered in the *** seismic response and collapse safety of topologically optimal SMA-BFs are assessed according to the FEMA P695 methodology.A comparative study on the optimal SMA-BFs is also presented in terms of total relative cost,collapse capacity,and peak and residual story *** results demonstrate that Fe-based SMA-BFs exhibit higher collapse capacity and more uniform distribution of lateral displacement over the frame height while being more cost-effective than NiTi braced *** addition to a lower unit price compared to NiTi,Fe-based SMAs reduce SMA material *** frames with Fe-based SMA braces,the SMA usage is reduced by up to 80%.The results highlight the need for using SMAs with larger recoverable strains.

关键词： topology optimization shape memory alloy Fe-based SMA steel braced frames performance-based seismic design collapse assessment