Engineering Commons^™

Sf6 Gas-Insulated 50-Kva Distribution Transformer Design, Okan Özgönenel, David Thomas, Ünal Kurt

Turkish Journal of Electrical Engineering and Computer Sciences

There are increasing environmental concerns such that governments are pressured to cooperate with international concurrences. One of the most harmful contaminants is mineral oil when it infiltrates the soil. Although it is a good material in the act of insulating in distribution/power transformers, it presents some environmental hazards and safety disadvantages. For this reason, gas-insulated transformers are considered particularly for hazardous locations. An oil-insulated distribution transformer of 50 kVA, 34.5/0.4 kV, and 50 Hz is investigated and converted to SF6 gas-insulated transformer in this study. The suggested distribution transformer model with SF6 insulated has many benefits, such as being explosion-proof …

A Low-Complexity Rare-Based 2-D Doa Estimation Algorithm For A Mixture Of Circular And Strictly Noncircular Sources, Kashif Shabir, Tarek Hasan Al Mahmud, Rui Zheng, Zhongfu Ye

Turkish Journal of Electrical Engineering and Computer Sciences

A new rank reduction (RARE)-based two-dimensional (2-D) direction of arrival (DOA) estimation algorithm is proposed considering a mixture of circular and strictly noncircular sources. To enhance array aperture, a geometry of three uniform linear arrays is considered and then treated as displaced arrays from a virtual array using a simple linear transformation. The received data and the conjugated counterpart are combined together, exploiting the noncircular property. Both sources can be estimated separately by designing and exploiting the distinctive nature of circular and noncircular steering vectors. However, a 2-D spectrum search would lead to a high computational complexity burden. To reduce …

Long-Term Multiobject Tracking Using Alternative Correlation Filters, Kemal Batuhan Başkurt, Refi̇k Samet

Turkish Journal of Electrical Engineering and Computer Sciences

We propose a real-time multiobject-tracking approach that is minimally affected by environmental conditions and target appearance change. The aim of the proposed approach is to track any object in a scene, regardless of object type, since tracking all of the objects in a scene is critical and widely used in surveillance applications. Thus, motion detection results are used to initialize the trackers. The proposed object-tracking approach is realized with two types of independent correlation filters estimating location and scale. Alternative correlation filters representing different appearances of the target are also proposed in order to increase the robustness of the approach …

Image Reconstruction For Frequency-Domain Diffuse Optical Tomography, Vicky Mudeng, Yun Priyanto, Andhika Giyantara

Turkish Journal of Electrical Engineering and Computer Sciences

The image reconstruction algorithm of diffuse optical tomography (DOT) is based on the diffusion equation and involves both the forward problem and inverse solution. The forward problem solves the diffusion equation using the finite element method for calculating the transmitted light distribution under the condition of presumed light source and optical coefficient. The inverse solution reconstructs the optical property coefficient distribution using Newton's method. The work within this study develops an image reconstruction algorithm for frequency-domain DOT. A numerical simulations approach to light propagation in the tissue is conducted, while the optical property is reconstructed employing data around the boundary. …

An Efficient Structure For T-Cntfets With Intrinsic-N-Doped Impurity Distribution Pattern In Drain Region, Ali Naderi, Maryam Ghodrati

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, by using impurity distribution engineering of drain region, an efficient structure is proposed for tunneling carbon nanotube field-effect transistors (T-CNTFETs). The drain region of the proposed structure consists of two parts. The impurity density of the part close to the channel is intrinsic and the other is n-type with constant density of 1 nm$^{-1}$. In conventional T-CNTFETs, heavily doped drain causes a spiky drop of potential energy around the channel to drain junction resulting in a pathway for carriers in the valence band to tunnel to the conduction band which means ambipolar behavior and large leakage current. …

Improved Transient Response Capacitor Less Low Dropout Regulator Employing Adaptive Bias And Bulk Modulation, Suresh Alapati, Sreehari Rao Patri

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a low quiescent current, fast settling time, and adaptively biased capacitor less low-dropout (LDO) regulator. The topology involves a segmented pass transistor with bulk modulation and adaptively biased current control stages to improve the transient performance. The bulk modulation of the pass transistor assists in fast settling of the output voltage. The frequency compensation makes the LDO voltage regulator stable adaptively over load current transitions. In addition, the biasing stage is designed such that it adapts to the load transitions while consuming the quiescent current abstemiously. This arrangement further improves settling time to be within 1 µs …

Design Of An On-Chip Hilbert Fractal Inductor Using An Improved Feed Forward Neural Network For Si Rfics, Akhendra Kumar Padavala, Bheema Rao Nistala

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents an efficient modeling of Hilbert fractal inductors by improved feed forward neural network trained hybrid particle swarm optimization and gravitational search algorithm (FNNPSOGSA). The proposed model computes the effective inductance value (L) and quality factor (Q) of Hilbert fractal inductors with metal trace width, effective fractal length, frequency, and oxide thickness as input parameters. In contrast to the traditional feed forward neural network, the proposed FNNPSOGSA has been designed with fewer hidden neurons with much-enhanced learning and generalization capabilities. As a consequence, the proposed model achieves better speed and is as accurate as electromagnetic simulations. From the …

An Enhanced Grey Wolf Optimization Algorithm With Improved Exploration Ability For Analog Circuit Design Automation, M A Mushahhid Majeed, Sreehari Rao Patri

Turkish Journal of Electrical Engineering and Computer Sciences

A novel circuit sizing technique with improved accuracy and efficiency is proposed to resolve the sizing issues in the analog circuit design. The grey wolf optimization (GWO) algorithm has the total number of iterations divided equally for exploration and exploitation, overlooking the impact of balance between these two phases, aimed for the convergence at a globally optimal solution. An enhanced version of a typical GWO algorithm termed as enhanced grey wolf optimization (EGWO) algorithm is presented with improved exploration ability and is successfully applied in analog circuit design. A set of 23 classical benchmark functions is evaluated and the outcomes …

Design Of A Fractional Order Pid Controller With Application To An Induction Motor Drive, Ashraf Saleem, Hisham Soliman, Serein Al-Ratrout, Mostefa Mesbah

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new method for designing a fractional-order proportional-integral-derivative (FO-PID) controller with an application to an induction motor drive is proposed. In the proposed method, the motor drive is modeled using an autoregressive with exogenous input (ARX) model whose parameters are experimentally identified using real I/O data. A genetic algorithm is then used to find the FO-PID parameters. To guarantee the robustness of the controller against load variations, minimax optimization is adopted. To validate the results, the proposed controller is applied to a real-life motor drive using a hardware-in-the-loop (HIL) simulator. The experimental results show that the proposed …

Human Sleep Scoring Based On K-Nearest Neighbors, Shahnawaz Qureshi, Seppo Karrila, Sirirut Vanichayobon

Turkish Journal of Electrical Engineering and Computer Sciences

Human sleep is one of the essential indicators that gauge the overall health and well-being. Presently, it is common for people to face issues related to sleep. Various biomedical signals including electroencephalogram (EEG), electrooculography (EMG), and electrooculography (EOG) are utilized in the diagnosis and during the treatment of sleep disorder cases. An automatic classification to diagnose sleep problems can help in the analysis of sleep EEG data. In this current study, an effort is made to classify the sleep stages from a single EEG channel (C4-A1) based on K-nearest neighbors (K-NN) with three alternative distance metrics. The Euclidean distance is …

Sign Language Recognition With Multi Feature Fusion And Ann Classifier, Sunitha Ravi, Maloji Suman, Polurie Venkata Vijay Kishore, Kiran Kumar Eepuri

Turkish Journal of Electrical Engineering and Computer Sciences

Extracting and recognizing complex human movements such as sign language gestures from video sequences is a challenging task. In this paper this kind of a difficult problem is approached with Indian sign language (ISL) videos. A new segmentation algorithm is developed by fusion of features from discrete wavelet transform (DWT) and local binary pattern (LBP). A 2D point cloud is formed from fused features, which represent the local hand shapes in consecutive video frames. We validate the proposed feature extraction model with state of the art features such as HOG, SIFT and SURF for each sign video on the same …

Improved Method Of Heuristic Classification Of Vowels From An Acoustic Signal, Josef Krocil, Zdenek Machacek, Jiri Koziorek, Radek Martinek, Jan Nedoma, Marcel Fajkus

Turkish Journal of Electrical Engineering and Computer Sciences

This paper describes research in the field of the improved methodology of the classification of vowels /a, a:/, /$\varepsilon$, $\varepsilon$:/, /ı, i:/, /o, o:/, and /u, u:/ (vowel symbols according to IPA, i.e. International Phonetic Alphabet). The aim is to develop an improved method enabling the automatic allocation of vowel symbols to the corresponding time segments of acoustic recordings of an undisturbed speech signal. The combined classification method is based on finding frequencies of the first two local maxims (formants) in a smoothed linear predictive amplitude spectrum (LPC, linear predictive coding) and zero-crossing values of each speech active voiced short-term …

Fpga Implementation Of A Low-Power And Area-Efficient State-Table-Based Compression Algorithm For Dslr Cameras, Mohd Rafi Lone, Najeeb Ud Din Hakim

Turkish Journal of Electrical Engineering and Computer Sciences

Small image acquisition devices like digital single lens reflex (DSLR) cameras most commonly use Joint Photographic Expects Group (JPEG) coding standard for lossy compression. Although JPEG is a simple coding standard, its compression efficiency is very low as compared to any typical state-of-the-art image coding standards like set partitioning in hierarchical trees (SPIHT). In this paper, a novel state-table-based SPIHT (STS) algorithm and its field programmable gate array (FPGA) implementation is proposed. The STS uses two small state-tables and two extremely small lists. The STS not only provides better compression efficiency than the state-of-the-art JPEG 2000 at high bit rates …

Path Loss Model For Indoor Emergency Stairwell Environment At Millimeter Wave Band For 5g Network, Ahmed Mohammed Alsamman, Tharek Abd Rahman, Mohd Nour Hindia, Jamal Nasir

Turkish Journal of Electrical Engineering and Computer Sciences

The unused millimeter-wave (mmWave) spectrum offers a superb opportunity to increase mobile broadband capacity due to the enormous amount of available bandwidth. Different candidate operating frequencies for 5G wireless networks are available at the mmWave band. For 5G wireless networks, the emergency case is one of the applications. This paper presents the outcome of indoor emergency stairwell measurement campaigns for 5G system at 26 GHz, 28 GHz, 32 GHz, and 38 GHz, which were conducted at the University Technology Malaysia, Kuala Lumpur, Malaysia. To effectively evaluate the performance of 5G wireless systems in these different bands, single- and multifrequency path …

Artificial Immune System Based Wastewater Parameter Estimation, Cengi̇z Sertkaya, Ni̇lüfer Yurtay

Turkish Journal of Electrical Engineering and Computer Sciences

The basis of a wastewater treatment system is to achieve the desired characteristics of the wastewater treatment process. An estimation of the obtained wastewater treatment characteristics provides the information needed to set up the current process steps, and it is important to have an optimum treatment. In this study, an artificial immune system (AIS) structure is developed to estimate important wastewater output parameters such as pH, DBO, DQO, and SS for the first time. The proposed AIS models are based on the clonal selection principle, and the dataset is provided from the University of California Irvine (UCI) Machine Learning Library. …

Horizontal Diversity In Test Generation For High Fault Coverage, Arbab Alamgir, Abu Khari Bin A'Ain, Norlina Paraman, Usman Ullah Sheikh, Ian Grout

Turkish Journal of Electrical Engineering and Computer Sciences

Determination of the most appropriate test set is critical for high fault coverage in testing of digital integrated circuits. Among black-box approaches, random testing is popular due to its simplicity and cost effectiveness. An extension to random testing is antirandom that improves fault detection by maximizing the distance of every subsequent test pattern from the set of previously applied test patterns. Antirandom testing uses total Hamming distance and total cartesian distance as distance metrics to maximize diversity in the testing sequence. However, the algorithm for the antirandom test set generation has two major issues. Firstly, there is no selection criteria …

Reconstructing Insect Pursuit Flight Kinematics In The Wild, Haribabu Boddeeti

Graduate Research Theses & Dissertations

With their agile maneuvers and aerodynamic feats, flying insects continue to inspire the design, sensing, and control of unmanned aerial vehicles. Among the different behaviors that such insects perform, the mating pursuit stands out in terms of the high speeds and quick turns that each insect performs during the chase. Despite their frequent occurrence in nature, pursuit events between mating insects are rarely analyzed. This is because mating events are difficult to film in the wild or elicit in laboratory settings. The long-term goal of this research is to quantify the kinematics of flying insects in pursuit. The specific objective …

Fundamental Studies Of Chemical Stability And Carrier Process In Hybrid Perovskite Materials, Jue Gong

Graduate Research Theses & Dissertations

This dissertation comprehensively studies the optoelectronic properties of organic-inorganic hybrid perovskites to fundamentally answer their foundations of outstanding performance on solar cells, photodetectors, nanowire lasers and other optoelectronic applications. Specifically, a novel type of charge carrier-lattice interaction was discovered in perovskite methylammonium lead iodide (CH3NH3PbI3), where photoluminescence lifetime of photoinduced carriers is strongly dependent on the rotational frequency of CH3NH3+, as modulated via substitution of hydrogens with deuterium atoms in the organic cation. In addition, two-dimensional Ruddlesden-Popper perovskite (CH3NH3)2Pb(SeCN)2I2 was first synthesized and characterized in the field, and its photoluminescence properties were systematically examined. The existence of intensive photoluminescence peak …

Investigating The Effects Of Orientation Control Of Graphene Nanoplatelet Suspensions By A Magnetic Field On The Viscosity Of A Nanofluid System, Radhika Iyer

Graduate Research Theses & Dissertations

In this investigation, the rheological behavior of paraffin oil containing diamagnetic suspensions is characterized under varying magnetic field conditions. The particles suspended in the white paraffin oil at mass concentrations of 0.1, 0.3, 0.5, 0.7 and 1% m/m are two-dimensional graphene nanoplatelets with an average thickness of 2 – 8 nm. Rheological experiments were conducted using a Brookfield DV2T viscometer with a modified cylindrical spindle over the range of shear rates between 192 s-1 to 1928 s-1. A Neodymium N42 ring magnet with a surface strength of 1.32 T generated the magnetic field conditions for the rheological experiments and was …

Driving Under Weather: An Exploration Of The Traveling Salesman Problem With Probabilistic Unfavorable Driving Conditions, Andrew Wright

Graduate Research Theses & Dissertations

Inclement weather has a visceral impact on transportation systems, but it has been made undeniably clear. Reliable ground transportation is absolutely fundamental in global logistics, and the need to deliver goods to customers in a timely manner has never been more important. The field of operations research offers some quality logistics problems with the foresight to provide efficient transportation solutions. One of the most prevalent problems in operations research is the Traveling Salesman Problem (TSP). Although much research has gone into solving the classic TSP and some of its variants, none have been truly dedicated to integrating meteorological sciences.

The …

Development Of A Multi-Robot Testbed For Direct Human-Swarm Interaction, Venkata Satya Kiran Maridi

Graduate Research Theses & Dissertations

Robotic swarms are well suited for missions that involve covering large areas such as environmental monitoring, search-and-rescue operations, as well as those that require fusing information from multiple sources such as target tracking and machine inspection. However, navigating a swarm of robots effectively requires performing higher-level functions that are typically executed by humans such as commanding them to stay close and guiding them along with a preplanned route. In this context, the ability of multiple robots to stay together autonomously significantly reduces the cognitive load on a human operator. The goal of this thesis is to design and build a …

Theoretical Study Of Laser-Assisted Machining On Silicon Nitride Hollow Ceramic Cylinder Using Finite Element Method, Mudassar Hussain Ansari Mohammed

Graduate Research Theses & Dissertations

The most commonly used technique for machining ceramics is diamond grinding. It accounts for up to 75% of the manufacturing costs resulting in high cost of the product. An LED bulb offering increased brightness, energy saving and long life by using ceramic integration to LED chips costs around 10 times to a normal LED bulb. Complex geometries used in electronics, medical surgeries, aerospace, and automobile industries require the use of costly molds or powder metallurgy for low batch production which does not justify the cost. Laser Assisted Machining (LAM) is a process that uses a laser to locally heat the …

Biomechanical Exposures Of Neck And Shoulder In Virtual Reality, Sai Akhil Penumudi

Graduate Research Theses & Dissertations

Virtual Environment pose certain potential postural discomfort or pain of the neck and shoulder that could be different from a real environment. There has been a lack of ergonomic guidelines for the Virtual Reality (VR) usage with the hand gesture interaction. The purpose of this study was to evaluate the effect of the vertical target locations on biomechanical exposures of the neck and shoulder and task performance during VR interactions. Twenty subjects performed standardized pointing and painting tasks with five different target locations (15° upward, neutral, 15° downward, 30° downward, and self-selected). Users’ postures, gravitational moments, muscle activities of the …

Implementation Of Systems-Level Learning In A Community College Mechatronics Program, Margie N. Porter

Graduate Research Theses & Dissertations

This is a qualitative case study of the complete implementation of systems-level learning (SLL) pedagogy throughout a mechatronics engineering department in a community college in the United States. SLL was developed from the German engineering apprenticeship model, resulting in engineering graduates with what our German counterparts call Handlungskompetenz. Graduates of these programs have the flexibility to quickly adapt to new engineering systems and situations in a self-directed way without months of on-the-job training. This skill is related to adaptive expertise and is not the type of skill traditionally taught to engineering students.

Chronological and descriptive analyses were performed on semi-structured …

Evaluating The Role Of Energy Demand Prediction And Renewable Energy Utilization On Energy Dependency Management: A Generic System Dynamics Model, Emad Rabiei Hosseinabad

Graduate Research Theses & Dissertations

Supplying energy has become one of the biggest concerns of developed countries due to the growing energy needs in the last decades. Security of energy supply has forced countries to rely more on energy imports from external sources, and become energy dependent to a greater extent. Utilizing available renewable energy resources has been characterized as a reliable indicator to mitigate energy dependency in countries as well as securing the supplying of energy-based needs in the future. This research explores the impact of renewable energies as trustful resources in mitigating energy imports form external sources with investigation of its viability with …

Surface Engineering And Monomer Design For Light-Mediated Ring Opening Metathesis Polymerization, Ishan A. Fursule

Theses and Dissertations--Chemical and Materials Engineering

Stimuli-responsive materials are changing the landscape of actuated materials, optoelectronics, molecular machines, solar cells, temporary memory storage, and biomedical materials. Specifically, photo-responsive polymers have gained acceleration in research and application since the last two decades in the form of a surface coating and micro-patterns. Light as a stimulus can be coherent, mono or polychromatic, tunable for power (intensity) and energy (wavelength), and has precise spatiotemporal control. Conventional surface coating techniques such as spin coating are unable to impart properties to the coatings in terms of sturdiness, homogeneity, uniformity over the complex surface, post deposition modification, and process efficiency. Also, in …

Understanding Carbohydrate Recognition Mechanisms In Non-Catalytic Proteins Through Molecular Simulations, Abhishek A. Kognole

Theses and Dissertations--Chemical and Materials Engineering

Non-catalytic protein-carbohydrate interactions are an essential element of various biological events. This dissertation presents the work on understanding carbohydrate recognition mechanisms and their physical significance in two groups of non-catalytic proteins, also called lectins, which play key roles in major applications such as cellulosic biofuel production and drug delivery pathways. A computational approach using molecular modeling, molecular dynamic simulations and free energy calculations was used to study molecular-level protein-carbohydrate and protein-protein interactions. Various microorganisms like bacteria and fungi secret multi-modular enzymes to deconstruct cellulosic biomass into fermentable sugars. The carbohydrate binding modules (CBM) are non-catalytic domains of such enzymes that …

Application Of Process Systems Engineering Tools And Methods To Fermentation-Based Biorefineries, Kwabena Darkwah

Theses and Dissertations--Chemical and Materials Engineering

Biofuels produced from lignocellulosic biomass via the fermentation platform are sustainable energy alternatives to fossil fuels. Process Systems Engineering (PSE) uses computer-based tools and methods to design, simulate and optimize processes. Application of PSE tools to the design of economic biorefinery processes requires the development of simulation approaches that can be integrated with existing, mature PSE tools used to optimize traditional refineries, such as Aspen Plus. Current unit operation models lack the ability to describe unsteady state fermentation processes, link unsteady state fermentation with in situ separations, and optimize these processes for competing factors (e.g., yield and productivity). This work …

Design And Analysis Of Curcumin Conjugated Poly(Beta-Amino Ester) Networks For Controlled Release In Oxidative Stress Environments, Carolyn T. Jordan

Theses and Dissertations--Chemical and Materials Engineering

Oxidative stress, the imbalance of free radical generation with antioxidant defenses, leads to cellular inflammation, apoptosis and cell death. This compromised environment results in debilitating diseases, such as oral mucositis (OM), atherosclerosis, and ischemia/reperfusion injury. Antioxidant therapeutics has been a proposed strategy to ameliorate these imbalances and maintain homeostatic environments. However, the success of these approaches, specifically curcumin, has been limited due to characteristics such as hydrophobicity and high reactivity when released as bolus doses to contest to oxidative stress induced diseases. The development of a controlled release system to aid in protection of the antioxidant capacity of curcumin, as …

The Development Of Microfluidic Devices For The Production Of Safe And Effective Non-Viral Gene Delivery Vectors, Jason Matthew Absher

Theses and Dissertations--Chemical and Materials Engineering

Including inherited genetic diseases, like lipoprotein lipase deficiency, and acquired diseases, such as cancer and HIV, gene therapy has the potential to treat or cure afflicted people by driving an affected cell to produce a therapeutic protein. Using primarily viral vectors, gene therapies are involved in a number of ongoing clinical trials and have already been approved by multiple international regulatory drug administrations for several diseases. However, viral vectors suffer from serious disadvantages including poor transduction of many cell types, immunogenicity, direct tissue toxicity and lack of targetability. Non-viral polymeric gene delivery vectors (polyplexes) provide an alternative solution but are …