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Full-Text Articles in Civil and Environmental Engineering

Prefabricated Timber Living: A Modular Sustainable Solution, Hannah Giang, Justin Huang May 2025

Prefabricated Timber Living: A Modular Sustainable Solution, Hannah Giang, Justin Huang

Architectural Engineering

This senior project is part of the Gateway Decathlon, a two-year, multidisciplinary design-build competition focused on innovative, sustainable housing solutions. Our team designed and constructed a one-story dwelling using cross-laminated timber (CLT) panels to promote low-carbon, industrialized building practices. The structure features a modular layout with sloped roofs and exposed timber interiors, combining environmental responsibility with architectural flexibility. Emphasizing prefabrication and off-site construction, the design supports efficient assembly and disassembly, reduced material waste, and minimal environmental impact. The result is a scalable, adaptable housing prototype aligned with the competition’s goals of creativity, sustainability, and innovation in residential construction.


Development Of Timber Bridge Railing And Approach Guardrail Transition, Aaron Lechtenberger May 2025

Development Of Timber Bridge Railing And Approach Guardrail Transition, Aaron Lechtenberger

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Timber bridges with transverse and longitudinal bridge decks are increasingly utilized across the United States. However, limited research exists to develop bridge railing systems for high-service-level roadways that meet current vehicular impact safety standards. In response to this gap, the United States Department of Agriculture - Forest Service -Forest Products Laboratory (USDA-FS-FPL), in collaboration with the Midwest Roadside Safety Facility (MwRSF), initiated a research program to develop, crash test, and evaluate higher-service-level bridge railings and approach guardrail transitions (AGTs) compliant with the American Association of State Highway and Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH).

This study continued …


Comparative Analysis On Design Error Risks In Design-Bid-Build And Design-Build Construction Approaches, Eradius Edward Rwakarehe Apr 2025

Comparative Analysis On Design Error Risks In Design-Bid-Build And Design-Build Construction Approaches, Eradius Edward Rwakarehe

Tanzania Journal of Engineering and Technology (TJET)

This study was conducted to compare design errors risk in Design-Bid-Build (DBB) (traditional) and Design-Build (DB) methods in building projects. Several construction projects under both DB and DBB method were reviewed. On most of construction projects under DB method, it was found that there were over supply of floor area due to different reasons. Also, it was found that, clients’ requirements were changed during project execution, which resulted into change on schedule, contract value and project quality. It was also revealed that in most cases, designs were in accordance with the clients’ requirements as submitted earlier but during construction clients …


Evaluation Of Chloride Diffusion In Concrete Using Bulk Diffusion Test And Scanning Electron Microscopy, Payton Davis Apr 2025

Evaluation Of Chloride Diffusion In Concrete Using Bulk Diffusion Test And Scanning Electron Microscopy, Payton Davis

Doctoral Dissertations and Master's Theses

Reinforced concrete is one of the most widely used construction materials in the world with many bridges and other major infrastructure consisting of such structural elements. A primary concern impacting the durability of concrete is chloride penetration in aggressive environments such as marine or coastal areas. In such environments, chloride ions can penetrate into the pores of concrete leading to the corrosion of embedded steel reinforcement which compromises the structural integrity of concrete. To investigate the issue, a comprehensive experimental program was designed and implemented which involved the preparation and testing of 31 different concrete mixes, each incorporating varying proportions …


Wind-Resilient Solar: Harnessing Cfd For Enhanced Load Estimation, Aly Mousaad Aly Apr 2025

Wind-Resilient Solar: Harnessing Cfd For Enhanced Load Estimation, Aly Mousaad Aly

Faculty Publications

Solar panels are a cornerstone of renewable energy infrastructure, playing a pivotal role in global sustainability efforts. To ensure their resilience and long-term viability, accurate wind load estimations are essential for designing supporting structures, which account for nearly 50% of their total cost. However, traditional building codes lack comprehensive guidance for solar panels, resulting in inconsistent estimations due to discrepancies in scaled wall-bounded wind tunnel testing methodologies. These inaccuracies pose safety risks, increase costs, and hinder adoption. Emerging technologies like computational fluid dynamics (CFD) simulations offer a promising alternative by enabling full-scale analysis under realistic conditions of complete turbulence. This …


Advancing Solar Farm Resilience: Cfd-Driven Wind Load Optimization, Aly Mousaad Aly Apr 2025

Advancing Solar Farm Resilience: Cfd-Driven Wind Load Optimization, Aly Mousaad Aly

Faculty Publications

This study investigates wind load design methods for ground-mounted solar panels and arrays by comparing Computational Fluid Dynamics (CFD) simulations with design standards. A case study of a solar farm impacted by Hurricane Maria examines the effects of elevation height, tilt angle, and variations in the American Society of Civil Engineers (ASCE) standards on wind loads and structural failure. Turbulence models, including Reynolds Stress Model, k–ε Model, and Large Eddy Simulation (LES), are used to analyze wind pressures, lift, drag, and peak pressures. Results show Phase 1 experienced higher wind loads than Phase 2 due to design differences. A cost-benefit …


Fast Penetration Test As An In-Situ Method For Assessing Buildability In 3d Concrete Printing, Ali Fasihi, Nicolas Ali Libre Apr 2025

Fast Penetration Test As An In-Situ Method For Assessing Buildability In 3d Concrete Printing, Ali Fasihi, Nicolas Ali Libre

Miners Solving for Tomorrow Research Conference

No abstract provided.


Digital Fabrication With Fiber-Reinforced Concrete, Haodao Li, Kamal H. Khayat Apr 2025

Digital Fabrication With Fiber-Reinforced Concrete, Haodao Li, Kamal H. Khayat

Miners Solving for Tomorrow Research Conference

No abstract provided.


Underlying Mechanisms Of The Effect Of Microfines Of Manufactured Sand On Non-Linear Structural Build-Up Of Cement Paste, Jiang Zhu, Jiaping Liu, Kamal H. Khayat, Xin Cheng, Wei Zhao, Zhen Li, Xin Shu, Yongbo Huang Apr 2025

Underlying Mechanisms Of The Effect Of Microfines Of Manufactured Sand On Non-Linear Structural Build-Up Of Cement Paste, Jiang Zhu, Jiaping Liu, Kamal H. Khayat, Xin Cheng, Wei Zhao, Zhen Li, Xin Shu, Yongbo Huang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The rheological properties of cement-based materials made with manufactured sand vary with the content and physio-chemical properties of microfines in the sand. However, the evaluation of rheological properties regarding the structural build-up at early-age hydration remains challenging for the cementitious materials prepared with different manufactured sands, due to complicated underlying structuration mechanisms. This paper studies the effect of disparate microfines of different manufactured sands on the non-linear growth of static yield stress of cement pastes at rest. The paste mixtures were prepared with 0.40 and 0.275 water-to-cement mass ratio (W/C) and had a fixed mini-slump flow of 240 ± 5 …


Quality Assurance Framework For Recovered Binders And Aggregates From Asphalt Mixtures Incorporating Recycled Materials, Eslam Deef-Allah, Magdy Abdelrahman Apr 2025

Quality Assurance Framework For Recovered Binders And Aggregates From Asphalt Mixtures Incorporating Recycled Materials, Eslam Deef-Allah, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study proposes that a proactive quality assurance (QA) framework for asphalt mixes with recycled materials, i.e., reclaimed asphalt pavement and recycled asphalt shingles, should be developed. Quality control (QC) is generally concerned with the contractor's obligation to produce mixes which meet the job mix formula (JMF) targets. However, QA considers the variability in fabrication processes and materials and offers monitoring by evaluating the contractor's performance. Although both aggregate gradations and asphalt contents were within the JMF specifications, the recovered binders revealed significant differences from the contract binders in the JMF. Rheological tests indicated increased stiffness and elasticity but reduced …


Experimental Investigation Of Multi-Cell Column Foun-Dations Under Bending Loads, Mostafa Abdo Abdllah Sharp Mar 2025

Experimental Investigation Of Multi-Cell Column Foun-Dations Under Bending Loads, Mostafa Abdo Abdllah Sharp

Journal of Engineering Research

This study investigates the structural behavior of connections between multi-cell columns and foundations under bending loads. The term "multi-cell" refers to sections with multiple longitudinal hollow cores separated by thin webs. A total of eight specimens were modeled and analyzed using the finite element software ABAQUS/CAE [1], under a single loading line system until failure. To facilitate this study, a control specimen was created as a benchmark, enabling the assessment of various parameters' impact on the connection. These parameters include embedment depth, the number of cells in the column, the presence of shear studs, internal plates, and concrete infill within …


The Performance Of Different Systems In Resisting Seismic Loading For High Rise Concrete Structures, Samy A. Fawzy Mar 2025

The Performance Of Different Systems In Resisting Seismic Loading For High Rise Concrete Structures, Samy A. Fawzy

Journal of Engineering Research

High-rise buildings are subjected to gravity and mostly lateral loading from seismic and wind loads that affect the behavior of such structures. In this study, we will deal with the seismic behavior of different concrete systems. Moment resisting frame, Shear wall, global bracing and dual system are used in this study. A 3D model in static and dynamic analysis was done using ETABS software then a pushover analysis and a parametric study as well for different systems. The study proved that the case of moment resisting frame is the worst in resisting displacements and drift as well. Although the model …


Numerical Analysis Of Cold-Formed Built-Up Battened Steel Columns Under Eccentric Compressive Loading, Mai Mohamed Sheta, Hanan Hussein Eltobgy, Mohamed Massoud El Saadawy, Khaled Abdallah Gharib Mar 2025

Numerical Analysis Of Cold-Formed Built-Up Battened Steel Columns Under Eccentric Compressive Loading, Mai Mohamed Sheta, Hanan Hussein Eltobgy, Mohamed Massoud El Saadawy, Khaled Abdallah Gharib

Journal of Engineering Research

This paper presents a 3D finite element model simulation using ABAQUS finite element software to investigate the behavior of steel battened beam columns under uniaxial loads. The columns consist of double-channel cold-formed slender open sections. The study highlighted the effects of various factors on the ultimate capacity of these beam-column members.

By considering both global and local imperfections, the model focuses on the structural strength and performance of battened cold-formed steel columns made from built-up sections. These cold-formed steel (CFS) columns have a slenderness ratio ranging from 50 to 162. Axial loads are applied at the pin-ended support of the …


Non-Linear Analysis Of Axially Loaded Built-Up Open Section Cold-Formed Columns, Mai Mohamed Sheta, Hanan Hussein Eltobgy, Mohamed Massoud El Saadawy, Khaled Abdallah Gharib Mar 2025

Non-Linear Analysis Of Axially Loaded Built-Up Open Section Cold-Formed Columns, Mai Mohamed Sheta, Hanan Hussein Eltobgy, Mohamed Massoud El Saadawy, Khaled Abdallah Gharib

Journal of Engineering Research

Built-up open cold-formed sections are commonly used in entrances, structural corners, and window frames. These elements exhibit low torsional stiffness and are highly susceptible to cross-sectional deformation. Battened built-up cold-formed steel (CFS) open columns offer enhanced load-carrying capacity when individual profiles cannot withstand applied loads.

Extensive research has focused on understanding the buckling behavior of these structural elements. However, limited studies have explored the impact of spacing between cold-formed C-channel sections. Existing research suggests that battened columns with adequately spaced members exhibit superior structural performance compared to those with closely spaced channels.

A critical factor affecting the performance of battened …


Numerical Study For Strengthening Hexagonal Castellated Steel Beams Using Hexagonal Ring Stiffeners, Amany M. Morad, Omnia F. Kharoub, Nashwa Yossef Mar 2025

Numerical Study For Strengthening Hexagonal Castellated Steel Beams Using Hexagonal Ring Stiffeners, Amany M. Morad, Omnia F. Kharoub, Nashwa Yossef

Journal of Engineering Research

This paper investigates numerically how the castellated steel beams are affected by the addition of hexagonal stiffeners around hexagonal web openings. Increasing the CSBs' load-bearing capacity and improving their overall structural behavior are the main objectives of this strengthening technique. Although there are different failure modes as a result of castellation, the main emphasis of this study is web post-buckling. Using ABAQUS software, a 3D finite element model is created to analyze the beam's behavior. The model's accuracy was validated by comparing its results with those from previous experimental studies. Failure loads, failure modes, and load-deflection curves of CSBs are …


Bell Ford Bridge Reconstruction Project, Daniel Kurdziel, Jim Barker, Matt Lee Mar 2025

Bell Ford Bridge Reconstruction Project, Daniel Kurdziel, Jim Barker, Matt Lee

Purdue Road School

The Bell Ford Bridge was originally constructed in 1869 until it collapsed in the 20th century. The remains were salvaged and stored for 20 years until it was to be rebuilt in Hamilton County, IN. This is the only remaining Combination Post Truss in existence and was rebuilt using 95% of the original iron and 10% of the original timber.


Correlating The Compositional Changes To The Rheological Properties Of Recovered Asphalt Binders From Recycled Asphalt Mixtures: Insights From The Thermogravimetric Measurements, Eslam Deef-Allah, Magdy Abdelrahman Mar 2025

Correlating The Compositional Changes To The Rheological Properties Of Recovered Asphalt Binders From Recycled Asphalt Mixtures: Insights From The Thermogravimetric Measurements, Eslam Deef-Allah, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Assessing the binder performance of thermal characterization is critical for quality control. This is pertinent for recovered binders from mixtures, which may not be in adequate quantities to evaluate their performance, particularly in mixtures containing reclaimed asphalt pavement (RAP). The present study deployed a thermogravimetric analyzer to evaluate compositional changes in recovered binders from RAP-containing mixtures, focusing on thermograph and derivative of thermograph (DTG) characteristics and correlating the results to rheological features. Incorporating RAP in mixtures influenced recovered binders' DTG shapes, reducing low-combusted components (%LCC) and increasing residues (%R). The recovered binder from the zero-RAP-containing mixture showed a 4.36% increase …


Impact Of Aggregate Characteristics On Frictional Performance Of Asphalt-Based High Friction Surface Treatments, Alireza Roshan, Magdy Abdelrahman Mar 2025

Impact Of Aggregate Characteristics On Frictional Performance Of Asphalt-Based High Friction Surface Treatments, Alireza Roshan, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

High Friction Surface Treatments (HFST) are recognized for their effectiveness in enhancing skid resistance and reducing road accidents. While Epoxy-based HFSTs are widely applied, they present limitations such as compatibility issues with existing pavements, high installation and removal costs, and durability concerns tied to substrate quality. As an alternative to traditional Epoxy-based HFSTs, this study investigated the effects of aggregate gradation as designated by agencies on the performance of asphalt-based HFST. Various aggregate types were assessed to evaluate friction performance and the impact of polishing cycles on non-Epoxy HFST. It was found that adjustments in aggregate size and gradation may …


Design Of An Electro-Hydraulic Laboratory Test System For Adjusting The Inclination Angle Of Sowing Machines, Aytac Moralar, Figan Dalmis, Bahattin Akdemir Mar 2025

Design Of An Electro-Hydraulic Laboratory Test System For Adjusting The Inclination Angle Of Sowing Machines, Aytac Moralar, Figan Dalmis, Bahattin Akdemir

The Philippine Agricultural Scientist

Field testing of grain sowing machinery requires favorable field conditions and sufficient time periods, making laboratory tests a preferred alternative for determining performance under controlled conditions. However, a standardized testing system for evaluating sowing machinery has not yet been established. In this study, a test system was designed for laboratory testing of universal grain sowing machines. A movable platform was built on a chassis made using sheet metal with different dimensions and profiles. It operates through a hydraulic system via a programmable logic controller-based control system. The sowing machine placed on this platform allows for inclination adjustments (front, back, right, …


Development Of Planetary Drive System For Formula Sae Electric Race Car, Brian Wong, Bradley Maruoka, Joshua Charles Fine, Madison Kai Mar 2025

Development Of Planetary Drive System For Formula Sae Electric Race Car, Brian Wong, Bradley Maruoka, Joshua Charles Fine, Madison Kai

Mechanical Engineering

Hub motors are compact electric motors mounted directly on each outboard wheel hub. Utilized in Formula SAE and Formula Student vehicles, this configuration offers several advantages over traditional drivetrains, including packaging optimization within the chassis, vehicle traction, and improved efficiency. Although hub motors are not yet common in 4WD vehicles, they are being explored for use in EVs and may become more common in the future. Every year, Cal Poly Racing FSAE designs and builds a formula-style race car. To improve drivetrain performance, the team is investigating the achievability of a hub motor 4WD drivetrain, requiring extensive research, development, and …


Proof Of Concept: Using Uas Technology To Accomplish Aerial Roof Inspections, Madison R. Fanning Mar 2025

Proof Of Concept: Using Uas Technology To Accomplish Aerial Roof Inspections, Madison R. Fanning

Theses and Dissertations

With the growing use of simulation across industries, the digital twin remains an underexplored research area, particularly in emergency management and response. Its real-time updating capability is often overlooked due to the misconception that "digital twin" is merely a complex term for simulation. This paper highlights its distinctiveness through an evasion exercise involving two independent entities in a collocated environment. Using a highly integrated virtual environment (HIVE) and internet of things (IoT) devices, we link the physical system with an analytical simulation, demonstrating the impact of lag times in high-pressure scenarios. The computational model leverages agent-based modeling (ABM) and discrete-event …


Flexural Strengthening Of Reinforced Concrete Beams Using Nsm Gfrp: Assessing Key Parameters, Berlant Arab Feb 2025

Flexural Strengthening Of Reinforced Concrete Beams Using Nsm Gfrp: Assessing Key Parameters, Berlant Arab

Theses and Dissertations

The structural integrity and longevity of Reinforced Concrete (RC) beams are critical to modern construction, influencing safety, usability, and maintenance costs over time. As civil engineering endeavors to meet the challenges posed by aging infrastructure and evolving usage demands, rehabilitating and strengthening RC structures have become essential practices globally. This research focuses on a prevalent yet innovative method of enhancing RC beams: the application of Near Surface Mounted (NSM) Glass Fiber Reinforced Polymer (GFRP) bars.

GFRP is increasingly favored in structural engineering due to its superior properties to traditional materials. These include high tensile strength, resistance to corrosion, lightweight nature, …


Simulation-Based Models For Postearthquake Response: A Survey And Research Directions, Abhijit Gosavi, Lauryn A. Spearing, Lesley H. Sneed Feb 2025

Simulation-Based Models For Postearthquake Response: A Survey And Research Directions, Abhijit Gosavi, Lauryn A. Spearing, Lesley H. Sneed

Engineering Management and Systems Engineering Faculty Research & Creative Works

Computer simulation is increasingly being used by emergency planners as a tool to improve disaster response given that it can model real-world scenarios, such as earthquakes. Although there has been an increase in simulation research focused on disaster response, much of this literature is from disparate fields and across disaster scenarios. To bridge this gap, this paper surveys simulation-based models for post-earthquake response from the year 2000 onward. Advantages of simulation over closed-form statistical models are discussed. Three main subproblems in post-earthquake response models are explored: (1) service distribution (e.g., food, water), (2) infrastructure restoration (at the building and transportation …


Effect Of Shrinkage-Mitigating Materials, Fiber Type, And Repair Thickness On Flexural Behavior Of Beams Repaired With Fiber-Reinforced Self-Consolidating Concrete, Jingjie Wei, Kamal H. Khayat Feb 2025

Effect Of Shrinkage-Mitigating Materials, Fiber Type, And Repair Thickness On Flexural Behavior Of Beams Repaired With Fiber-Reinforced Self-Consolidating Concrete, Jingjie Wei, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While self-consolidating concrete (SCC) has emerged as a highly effective approach for the repair of concrete structures, there have been few investigations regarding the effect of the combination of different fiber and shrinkage-mitigating material types (shrinkage-reducing admixture, SRA; superabsorbent polymer, SAP; and expansive agent, EA) on the flexural behavior of repaired structures. This study aims to explore the influence of three different shrinkage-mitigating materials (1.25%–2.5 % SRA, 4%–8% EA, and 0.2%–0.4 % SAP), four fiber types (two macro synthetic fibers, MSFA and MSFB; 5D hooked steel fibers, 5D; a combination of 80 % 3D hooked steel +20 % short steel …


Optimization Of The Cross-Section Of Generic Flexible Bridges, Manal Kamal Zaki, Mina M. Helmy, Mark M. Tawadros Jan 2025

Optimization Of The Cross-Section Of Generic Flexible Bridges, Manal Kamal Zaki, Mina M. Helmy, Mark M. Tawadros

Journal of Engineering Research

This paper investigates the behavior of flexible bridges prone to aerodynamic instabilities due to wind. Optimal cross-sections that reduce aerodynamic forces are recommended. This is achieved by studying a variety of bridge sections with different widths of upper and lower sloping edges in addition to studying the upper and lower cramps of the deck. The wind velocities are also parameterized. Computations are developed based on the powerful computational fluid dynamics (CFD) method known as FLUENT and embedded in ANSYS software. For parametric study, a design of experiments (DOE) is performed based on the response surface methodology (RSM) combined with the …


Preliminary Spectral Matching Analysis Of The Rod El-Farag Region In Cairo, Egypt, Ahmed F. Youssef, Amr Z. Elkady, Ayman A. Seleemah Jan 2025

Preliminary Spectral Matching Analysis Of The Rod El-Farag Region In Cairo, Egypt, Ahmed F. Youssef, Amr Z. Elkady, Ayman A. Seleemah

Journal of Engineering Research

Abstract: Earthquake engineering assessments are essential for evaluating the seismic response of structures. Nonlinear dynamic analysis is a highly effective method for evaluating seismic re-sponse, considering the complex, three-dimensional, and dynamic behaviour of structures during earthquakes. The complexity of seismic damage assessment arises from ground motion and struc-tural modelling parameters. Spectral matching is a key method in seismic codes and aids in selecting earthquake accelerograms for performance- and force-based designs. Spectrum-matched data is increasingly used to estimate nonlinear structural responses. Spec-tral matching utilizes the wavelet adjustments introduced by Abra-hamson (1992) and refined by Hancock et al. (2006) to adjust earth-quake …


Optimizing And Validation Of Sustainable Uhpc With Waste Glass Powder Utilizing Modified Particle Packing Approach And Response Surface Methodology, Mohamed Taman, Elsaid Maaty, Alaa Mehrez, Ahmed Kamal Isaac Jan 2025

Optimizing And Validation Of Sustainable Uhpc With Waste Glass Powder Utilizing Modified Particle Packing Approach And Response Surface Methodology, Mohamed Taman, Elsaid Maaty, Alaa Mehrez, Ahmed Kamal Isaac

Journal of Engineering Research

The current study explores the potential of utilizing Waste glass powder (WGP) as an alternative to cement in the development of sustainable eco-friendly Ultra-high-performance concrete (UHPC). UHPC mixtures underwent optimization through the application of a Modified Andreasen and Andersen (MAA) particle packing model, resulting in a reduction of cement content from 900 to 800 kg/m3. Six mixes were cast, with varying levels of cement replacement ratios with WGP up to 50%. The evaluation focuses on the flowability, dry density, and mechanical properties of UHPC at different ages using normal curing. A statistical model utilizing response surface methodology (RSM) …


Review On State Of Art Of Smoothed Particle Hydrodynamics Method And Its Advances In Solid Dynamics, Harold J. Mtyana Jan 2025

Review On State Of Art Of Smoothed Particle Hydrodynamics Method And Its Advances In Solid Dynamics, Harold J. Mtyana

Tanzania Journal of Engineering and Technology (TJET)

The world is witnessing continued collapse of both buildings and other structures during earthquakes, which is an example of a dynamic effect. One cause of such disasters may be inadequacies of techniques for modeling of these structures during analysis and design as compared to their actual responses during dynamic events. Also, techniques for numerical modeling and analysis of structures in place are meshed methods which do not accurately capture the actual behavior of structural elements especially under high dynamic actions due to the assumption that mesh geometry is unchanged geometry tend to change with respect to time step of such …


Improved Minimum Variance Channel Estimation Techniques For Ofdm Systems, Kwame S. Ibwe Jan 2025

Improved Minimum Variance Channel Estimation Techniques For Ofdm Systems, Kwame S. Ibwe

Tanzania Journal of Engineering and Technology (TJET)

Orthogonal frequency division multiplexing (OFDM) systems face challenges in channel estimation due to noise, variability, and the doubly dispersive nature of wireless channels, which degrade performance. To address these challenges, a multichannel minimum variance double dispersive channel estimator is proposed. The method employs a hybrid approach that combines subspace and minimum variance techniques, optimizing the filter bank output power under a signal-to-noise ratio (SNR) constraint. This design preserves the desired signal while effectively suppressing disturbances, achieving robust performance with reduced computational complexity compared to existing methods. Simulation results demonstrate that the proposed estimator outperforms subspace and asymptotic methods in terms …


Design And Implementation Of Secured Hybrid Gateway Node For Securing Iot - Enabled Distribution Automation, Ally Bitebo Jan 2025

Design And Implementation Of Secured Hybrid Gateway Node For Securing Iot - Enabled Distribution Automation, Ally Bitebo

Tanzania Journal of Engineering and Technology (TJET)

The integration of smart grid and Internet of Things (IoT) technologies plays a crucial role in enhancing the quality of services provided by traditional electrical grids. This combination has enabled the introduction of new services, such as demand response, automatic meter reading, and IoT-enabled Distribution Automation (IoT-DA), which incorporates sensors, actuators, intelligent electrical devices (IEDs), and information and communication technologies to monitor and control the grid. However, this integration also introduces network security risks, including Denial of Service (DoS) attacks, false data injection, and masquerading attacks, such as system node impersonation that can transmit incorrect readings, trigger false alarms, and …