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Bifurcation Analysis and Bounded Optical Soliton Solutions of the Biswas-Arshed Model

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 2197-2217页

作者： Fahad Sameer Alshammari md.fazlul Hoque Harun-Or-Roshid Muhammad Nadeem Department of Mathematics College of Science at AlkharjPrince Sattam bin Abdulaziz UniversityAlkharj11942Saudi Arabia Department of Mathematics Pabna University of Science and TechnologyPabna6600Bangladesh Faculty of Science Yibin UniversityYibin644000China

We investigate the bounded travelling wave solutions of the Biswas-Arshed model(BAM)including the low group velocity dispersion and excluding the self-phase *** integrate the nonlinear structure of the model to obtain bounded optical solitons which pass through the optical fibers in the non-Kerr *** bifurcation technique of the dynamical system is used to achieve the parameter bifurcation sets and split the parameter space into various areaswhich correspond to different phase *** bounded optical solitons and bounded periodic wave solutions are identified and derived conforming to each region of these phase *** also apply the extended sinh-Gordon equation expansion and the generalized Kudryashov integral schemes to obtain additional bounded optical soliton solutions of the BAM *** present more bounded optical shock waves,the bright-dark solitary wave,and optical rogue waves for the structure model via these schemes in different aspects.

关键词： The Biswas-Arshed model the extended sinh-Gordon equation expansion the generalized Kudryashov approach shock wave double solitons optical singular double solitons chirp-free bright-dark double solitons

Self-centring segmental retaining walls—A new construction system for retaining walls

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 980-1000页

作者： Mehdi JAVADI Reza HASSANLI md.Mizanur RAHMAN md.Rajibul karim UniSA STEM University of South AustraliaMawson Lakes5095Australia

This paper reports on an experimental study on a new self-centring retaining wall *** post-tensioned segmental retaining walls(PSRWs)were experimentally *** of the walls was constructed using seven T-shaped concrete segments with a dry *** walls were tested under incrementally increasing cyclic lateral *** effect of the wall height,levels of post-tensioning(PT)force,and bonded versus unbonded condition of PT reinforcement on the structural behavior of the PSRWs was *** results showed that such PSRWs are structurally adequate for water retaining *** to the results,increasing the wall height decreases initial strength but increases the deformation capacity of the *** larger deformation capacity and ductility of PSRW make it a suitable structural system for fluctuating loads or deformation,e.g.,*** was also found that increasing the PT force increases the wall’s stiffness;however,reduces its *** residual drift and the extent of damage of the unbonded PSRWs were significantly smaller than those of the bonded *** suggest that this newly developed self-centring retaining wall can be a suitable structural system to retain lateral *** to its unique deformation capacity and self-centring behavior,it can potentially be used for seawall application.

关键词： retaining wall segmental precast concrete unbonded post-tensioning water retaining wall seawall

Behaviour of self-centring shear walls——A state of the art review

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Frontiers of Structural and Civil Engineering 2023年第1期17卷 53-77页

作者： Mehdi JAVADI Reza HASSANLI md.Mizanur RAHMAN md.Rajibul karim UniSA STEM University of South AustraliaAdelaide 5095Australia

The application of unbonded post-tensioning (PT) in structural walls has led to the development of advanced self-centring (rocking) shear wall systems that has significant advantages, including accelerated construction due to the incorporation of prefabricated elements and segmental construction for different materials (e.g., concrete, masonry, and timber), reduced residual drifts, and little damage upon extreme seismic and wind loads. Concrete, masonry, and timber are often used for the construction of unbonded PT structural wall systems. Despite extensive research since the 1980s, there are no well-established design guidelines available on the shear wall configuration with the required energy dissipation system, joint’s locations and acceptance criteria for shear sliding, confinement, seismic performance factors, PT loss, PT force range and residual drifts of shear walls subjected to lateral loads. In this research a comprehensive state-of-the-art literature review was performed on self-centring shear wall system. An extensive study was carried out to collect a database of 100 concrete, masonry, and self-centring shear wall tests from the literature. The established database was then used to review shear walls’ configurations, material, and components to benchmark requirements applicable for design purposes. The behaviour of concrete, masonry and timber shear walls were compared and critically analysed. The general behaviour, force-displacement performance of the walls, ductility, and seismic response factors, were critically reviewed and analysed for different self-centring wall systems to understand the effect of different parameters including configurations of the walls, material used for construction of the wall (concrete, masonry, timber) and axial stress ratio. The outcome of this research can be used to better understand the behaviour of self-centring wall system in order to develop design guidelines for such walls.

关键词： self-centring shear walls rocking walls energy dissipation seismic performance factors PT loss residual drift

Bianchi Type-I Anisotropic Universe with Metric Potential in Saez-Ballester Theory of Gravitation

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Journal of Applied Mathematics and Physics 2022年第10期10卷 3072-3082页

作者： md. Rezaul karim Department of Mathematics University of Creative Technology Chittagong (UCTS) Chittagong Bangladesh

Bianchi Type-I cosmological model in the presence of Saez-Ballester theory gravitation is studied. An exact solution of the field equation is given by considering the cosmological model yield a metric potential included with a real number. The relation between the deceleration parameter and Hubble parameter and average scale factor is used in that cosmological model. The effect of the viscosity on the entropy of the universe is utilized by energy momentum tensor with bulk viscous terms in a conservative manner. We obtained a formula for calculating the entropy of the universe in terms of viscosity and used it to compare to the study. Also, various physical and kinematical properties have been discussed.

关键词： Bianchi Type-I Space Time Saez-Ballester Theory Energy Momentum Tensor Bulk Viscosity Hubble and Deceleration Parameter

A modified gas flow model in the near wellbore region below dew point pressure

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Petroleum 2021年第3期7卷 294-302页

作者： Abed Inan Chowdhury md.Mostafijul karim Department of Petroleum and Mining Engineering Chittagong University of Engineering&TechnologyChittagongBangladesh

When pressure in gas reservoirs fall below the dew point,condensate banking occurs around the wellbore which alters the fluid flow *** state of the knowledge on this flow behavior is yet not fully-developed;which leads to severe problems in *** this study,the Al-Hussainy,Ramey,and Crawford Solution Technique has been modified to accurately resemble the real gas flow behavior for this ***,a primary investigation was conducted to observe the severity of the problem in three condensate banked *** this study involved Constant Composition Expansion tests for determining the dew point,Prode Properties software for modeling the reservoir fluid properties,Flowing Material Balance(or Dynamic P/Z Material Balance)for identifying the pressure distribution of the selected *** real field data along with the determined(analytical,computational,and experimental)data were incorporated to check the validity of the *** modification proposes a Dimensionless Correction Factor(CD)for any condensate banked reservoir and identifies parameters such as the Perforation Factor(Pf)and Heterogeneity Factor(n).It is found that the Modified Al-Hussainy,Ramey,and Crawford Solution Technique successfully models the actual flow characteristics of the stated condition.

关键词： Condensate banking Effective permeability Gas flow modeling Model fitting

Dubin-Johnson syndrome with systemic lupus erythematosus: a case report

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Hepatobiliary & Pancreatic Diseases International 2006年第4期5卷 617-619页

作者： Mamun-Al Mahtab md. Fazal karim Salimur Rahman Abul Barkat Muhammad Adnan Department of Hepatology Bangabandhu Sheikh Mujib Medical University Dhaka Bangladesh

BACKGROUND: Dubin-Johnson syndrome (DJS) is a rare clinical entity. We describe a case of DJS complicated by systemic lupus erythematosus (SLE). METHODS: A case of congenital hyperbilirubinemia with SLE was evaluated systematically including review of history, physical examination for the stigmata of chronic liver disease, and other investigations. RESULT: Liver biopsy revealed a black liver with preserved architecture suggestive of DJS. CONCLUSIONS: SLE may develop in DJS. The relationship between DJS and SLE in this case is most likely a chance occurrence.

关键词： Dubin-Johnson syndrome systemic lupus erythematosus conjugated hyperbilirubinemia autoimmune disorder chance occurrence

Designing a Model to Study Data Mining in Distributed Environment

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Journal of Data Analysis and Information Processing 2021年第1期9卷 23-29页

作者： md. Abadur Rahman Masud karim School of Business & Tourism Southern Cross University Sydney Australia Department of Computer Science & Engineering Daffodil Institute of Science & Technology Dhaka Bangladesh

To make business policy, market analysis, corporate decision, fraud detection, etc., we have to analyze and work with huge amount of data. Generally, such data are taken from different sources. Researchers are using data mining to perform such tasks. Data mining techniques are used to find hidden information from large data source. Data mining is using for various fields: Artificial intelligence, Bank, health and medical, corruption, legal issues, corporate business, marketing, etc. Special interest is given to associate rules, data mining algorithms, decision tree and distributed approach. Data is becoming larger and spreading geographically. So it is difficult to find better result from only a central data source. For knowledge discovery, we have to work with distributed database. On the other hand, security and privacy considerations are also another factor for de-motivation of working with centralized data. For this reason, distributed database is essential for future processing. In this paper, we have proposed a framework to study data mining in distributed environment. The paper presents a framework to bring out actionable knowledge. We have shown some level by which we can generate actionable knowledge. Possible tools and technique for these levels are discussed.

关键词： Data Mining Distributed Database Knowledge Discovery Classification Algorithm

Numerical Study of Unsteady Behavior of Partial Cavitation on Two Dimensional Hydrofoils

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Journal of Shipping and Ocean Engineering 2012年第1期2卷 10-17页

作者： md. Nur-E-Mostafa md. Mashud karim md. Manirul Alam Sarker Department of Environment and System Sciences Graduate School of Environment and Information Science Yokohama National University Yokohama 240-8501 Japan Department of Naval Architecture and Marine Engineering Bangladesh University of Engineering and Technology Dhaka 1000 Bangladesh Department of Mathematics Bangladesh University of Engineering and Technology Dhaka 1000 Bangladesh

This paper deals with time dependent performance characteristics of cavitating hydrofoils, the flow around which has been simulated using pressure-based finite volume method. A bubble dynamics cavitation model was used to investigate the unsteady behavior of cavitating flow and describe the generation and evaporation of vapor phase. For choosing the turbulence model and mesh size a non cavitating study was conducted. Three turbulence models such as Spalart-Allmaras, Shear Stress Turbulence （SST） κ-ω model, Re-Normalization Group （RNG） κ-ε model with enhanced wall treatment are used to capture the turbulent boundary layer along the hydrofoil surface. The cavitating study presents an unsteady behavior of the partial cavity attached to the foil at different time steps for σ = 0.8 and σ = 0.4. Moreover, this study is focused on cavitation inception, the shape and general behavior of sheet cavitation, lift and drag forces for different cavitation numbers.

关键词： Cavitation CAV2003 hydrofoil finite volume method turbulence model unsteady flow.

Dicyclopentamethylenethiuram Disulfide as Precursor of Mononuclear Complexes: Oxidative Cleavage of Metal-Metal Bond in [CpMo(CO)3]2and Molecular Structure of cis-[CpMo(CO)2{S2C-N(CH2)5}]

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Crystal Structure Theory and Applications 2017年第4期6卷 67-72页

作者： md. Manzurul karim Shafikul Islam md. RafikulIslam Mohammad R. karim Tasneem A. Siddiquee Department of Chemistry Jahangirnagar University Savar Bangladesh Department of Chemistry Morning Glory School and College Savar Bangladesh Department of Chemistry Barisal Cadet College Barisal Bangladesh Department of Chemistry Tennessee State University Nashville TN USA

The reaction of [CpMo(CO)3]2 with dicyclopentamethylenethiuram disulfide in refluxing xylene resulted a novel mono nuclear complex, cis-[(CpMo(CO)2{S2C-N(CH2)5}] as red crystals in moderate yield. The compound was formed by the oxidative cleavage of metal-metal bond in [CpMo(CO)3]2 together with a reductive sulfur-sulfur bond scission in the ligand.

关键词： Dicyclopentamethylenethiuram Disulfide (Dcpmtd) Oxidation Number Oxida-tive Cleavage Coordination Number Mononuclear Complex X-Ray Crystal Structure