Engineering Commons^™

Structure Analysis Of Pemfc Cathode Catalyst Layer, Rui-Qing Wang, Sheng Sui

Journal of Electrochemistry

The sluggish oxygen reduction reaction (ORR) on the cathode of the proton exchange membrane fuel cell (PEMFC) has always been one of the key factors limiting its commercialization. The optimization of the cathode catalytic layer structure plays an important role in improving fuel cell performance and reducing production costs. In this paper, two different catalysts (platinum nanoparticles (Pt-NPs) and platinum nanowires (Pt-NWs)) were prepared by using catalyst coated substrate (CCS) method. By constructing a double-layer catalytic layer structure, we analyzed the effect of different catalytic layer structures by performing a single cell test. The results showed that the dense platinum …

Machine Learning Based Critical Resource Allocation In Mixed-Traffic Cellular Networks, Mohamed Nomeir

Theses and Dissertations

The proliferation of cellular networks over the past two decades has encouraged the expansion of their use in many modern applications. These applications involve the use of data traffic of different quality of service (QoS) requirements. Some of these requirements are quite stringent such as in the case of critical Internet of Things (IoT) health care, military and homeland security applications. This situation resulted in imposing a variety of resource allocation requirements on the cellular network operation in a simultaneous manner.

In this thesis, we consider the challenging problem of mixed-traffic resource allocation, or scheduling, in cellular networks. We focus …

Imitation Models Of The Railway Organization For Railway Transport Flows, J Usmonov, T Djuraev

Technical science and innovation

Considered the questions of solving the problem of optimization of cargo traffic management in the railway transport throughout the logistics chain, organizing the formation and implementation of cargo loading plans that do not allow exceeding the maximum and reduce the minimum levels of availability of a particular cargo on the destination road. And also the article justifies the solution of the problem of finding the maximum flow in the railway network, it is noted that in any transport network the maximum flow is equal to the minimum capacity. If the flow is maximal, then there is a section whose transmission …

Evaluation Of The Thickness Of Vacuum Metal And Semiconductor Coatings Using Computer Programs, Bahrom Igamov, Ilkhom Bekpulatov, Aleksey Kamardin, Tulkun Kamilov, Ilhom Turapov, D Igamova

Technical science and innovation

Comparative studies of the thickness of coatings of such metals as Cu, Ag, Cr, Co, and also Mn4 Si7 on polished substrates made of Si, Si O2 / Si structure, ST - 50 glass ceramic, mica were carried out. The coatings were deposited in vacuum using thermal evaporation and magnetron sputtering. The thickness and uniformity of deposited coatings on rotating substrates are estimated by optical measurements and computer simulation. Mathematical models for the formation of coatings on flat substrates have been developed. The possibility of the optimal position of the substrate for the formation of functional coatings uniform in thickness …

Uncertainty Of The Ultrasonic Method For Determining The Strength Of Concrete, Ortagoli Sharipovich Hakimov, Zamira Khudoyberdiyevna Ernazarova

Chemical Technology, Control and Management

The issues of measuring the strength of concrete by the method of surface sounding by ultrasound are considered. A measurement model and formulas for estimating the total standard measurement uncertainty, information about the standards used, measurement tools and methods, and environmental parameters are given. Information about the estimation of uncertainty in the form of "eight steps", such as: measurement task; mathematical model of measurement; analysis of input values; observation results; correlations; uncertainty budget; expanded uncertainty; measurement result. It has been established that the uncertainty of type B of the ultrasonic method for determining the strength of concrete is much less …

Algorithm For Calculating The Parameters Of A Multi-Position Electromagnetic Linear Mechatronic Module, Nazarov Khayriddin Nuritdinovich, Matyokubov Nurbek Rustamovich, Temurbek Omonboyevich Rakhimov

Chemical Technology, Control and Management

Currently, in the world in the field of science, engineering and technology, including in mechatronics and robotics, the creation of multi-coordinate mechatronic systems that perform power and control functions is becoming of paramount importance, this is due to a number of important positive qualities of the systems, such as simplicity and compactness of the design, the possibility of obtaining significant efforts, high accuracy and stability of the establishment of fixed positions, ease of control and high reliability. This article presents the calculation of the parameters of multi-position mechatronic modules based on linear execution elements. In the construction of this model, …

Mathematical Modeling Of Processes Of Diagnostics Of Technical And Technological Objects, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev

Chemical Technology, Control and Management

The work is an introduction to the technical diagnostics of technical (or technological) objects. It discloses the basic concepts and definitions of the reliability of dynamic systems as objects of diagnostic reference knowledge and their diagnosis. Structural schemes of diagnosing objects with individual and combined channels of influence are analyzed. Questions of rational construction of base of reference knowledge are stated.

Virtual Analyzers For Increasing The Intelligence Of Industrial Process Control Systems, Umidjon Abdimajotovich Ruziev Phd, Marufjon Kobuljanovich Shodiev

Chemical Technology, Control and Management

It is shown that the development and implementation of virtual analyzers of the quality of the final industrial products is an effective tool for increasing the efficiency of industrial production. The methodology and stages of development of virtual analyzers for predicting the quality of products, monitoring non-measurable or difficult-to-measure parameters of continuous and periodic technological processes are considered, and issues of supporting and adapting a virtual analyzer during its operation without restructuring are also considered.

Design Lifecycle Management Of Technological Processes, Yusuf Shodiyevich Avazov

Chemical Technology, Control and Management

The issues of life cycle management of design processes of complex technological processes are considered. An analysis of works devoted to the automated design of technological processes and industries, product life cycle management, and the use of predominant modeling in design is presented. A structure for the implementation of the design of technological processes is proposed and it’s components are described. An algorithm is proposed to reduce the life cycle of the design of a technological process. The sequence of selection of the most optimal project options with the help of the proposed algorithm is described. It is shown that …

Predictive Analysis And Synthesis, Modeling And Control Of Complex Technological Processes And Systems, Zhahongir Sherboyevich Bekqulov

Chemical Technology, Control and Management

Consider the theoretical underpinnings of practically predictive analysis and synthesis, modeling and automatic control of complex chemical technological processes and systems, and the evolution of advanced (or advanced) APC (Advanced Process Control) control of technological processes and industries. The current state of industrial automation systems and the characteristics of their deployment are highlighted. The features of each stage of the analysis and synthesis of APC - advanced process control for complex dynamic objects are disclosed. The real situation and features of the implementation of industrial automation systems of industrial enterprises are reflected.

New Transformer Changer Static Characteristics Measuring Angle Silences Difference, Sultan Faizullayevich Аmirov, Nurulla Raxmatullayevich Yuldashev

Chemical Technology, Control and Management

Presented the specific features of the new transformer converter, which measures the difference in angular displacement, and examines the nonlinearity levels of static characteristics, sensitivity and static characteristics. Studies have shown that in a new measuring device, where one of the two moving parts consists of a magnetic conductor made in the form of an Archimedean spiral made of ferromagnetic material, the balance of the magnetic bridge changes not only depending on the angle of rotation of it’s shoulder resistances. the current is disturbed by the change in the magnitude of the combined air gap depending on the angle of …

Quality Control Of Combustion Of Gaseous Fuel In Furnaces, Azamat Toirovich Rajabov

Chemical Technology, Control and Management

The issues of research and development of systems for monitoring the availability and quality of the process of fuel combustion in industrial furnaces are interpreted. The perspective of using new elements in control systems - communication sensors for the presence and quality in gas-burning installations and furnaces are shown. A method has been developed to control the optimal aeration coefficient based on the extreme of the total integral amplitude-frequency characteristic of the flame conductivity pulsations, which makes it possible to control the quality characteristics of gas-burner devices and control the ratio of the components of the combustible mixture with high …

Regular Algorithms For Adaptive Identification Of Linear Non-Stationary Systems, H.Z. Igamberdiyev, H.I. Sotvoldiev, U.F Mamirov

Chemical Technology, Control and Management

The article deals with the formation of regular algorithms for adaptive parametric spline identification of linear non-stationary systems. Analyzed the issues of constructing adaptive identification of continuous linear non-stationary systems with monotonic and sign-constant parameters. In this case, in a non-stationary system, the entire observation interval is in some way divided into sub-intervals. Identification is carried out at each of the parameter constancy intervals, while the parameter matrix is re-evaluated for the next interval. The input data of the system are determined with an error depending on the error of approximating the state of the system by splines and approximating …

Developing Advanced Process Control System For Manufacturing Processes Using Virtual Analyzer, Elyor Erkinovich Samadov

Chemical Technology, Control and Management

This research reflects outlines the main potential features of Advanced Process Control (APC) systems for improved control of technological processes and production. It is shown developing APC systems using a virtualized analyzer (VA) is a very effective technique to increase the efficiency of industrial production. This research reflects the main steps of generating VA as part of the APC system and also describes the key features of each step-in terms of analyzer synthesis.

Exciton Delocalization And Scaffold Stability In Bridged Nucleotide-Substituted, Dna Duplex-Templated Cyanine Aggregates, Simon K. Roy, Olga A. Mass, Donald L. Kellis, Christopher K. Wilson, John A. Hall, Bernard Yurke, William B. Knowlton

Electrical and Computer Engineering Faculty Publications and Presentations

Molecular excitons play a foundational role in chromophore aggregates found in light-harvesting systems and offer potential applications in engineered excitonic systems. Controlled aggregation of chromophores to promote exciton delocalization has been achieved by covalently tethering chromophores to deoxyribonucleic acid (DNA) scaffolds. Although many studies have documented changes in the optical properties of chromophores upon aggregation using DNA scaffolds, more limited work has investigated how structural modifications of DNA via bridged nucleotides and chromophore covalent attachment impact scaffold stability as well as the configuration and optical behavior of attached aggregates. Here we investigated the impact of two types of bridged nucleotides, …

Nondestructive Detection Of Codling Moth Infestation In Apples Using Pixel-Based Nir Hyperspectral Imaging With Machine Learning And Feature Selection, Nader Ekramirad, Alfadhl Y. Khaled, Lauren E. Doyle, Julia R. Loeb, Kevin D. Donohue, Raul T. Villanueva, Akinbode A. Adedeji

Electrical and Computer Engineering Faculty Publications

Codling moth (CM) (Cydia pomonella L.), a devastating pest, creates a serious issue for apple production and marketing in apple-producing countries. Therefore, effective nondestructive early detection of external and internal defects in CM-infested apples could remarkably prevent postharvest losses and improve the quality of the final product. In this study, near-infrared (NIR) hyperspectral reflectance imaging in the wavelength range of 900–1700 nm was applied to detect CM infestation at the pixel level for three organic apple cultivars, namely Gala, Fuji and Granny Smith. An effective region of interest (ROI) acquisition procedure along with different machine learning and data processing …

Temperature-Immune Self-Referencing Fabry–Pérot Cavity Sensors, Hengky Chandrahalim, Jonathan W. Smith

AFIT Patents

A passive microscopic Fabry-Pérot Interferometer (FPI) sensor an optical fiber a three-dimensional microscopic optical structure formed on a cleaved tip of an optical fighter that reflects a light signal back through the optical fiber. The reflected light is altered by refractive index changes in the three-dimensional structure that is subject to at least one of: (i) thermal radiation; and (ii) volatile organic compounds.

Comparative Analysis Of Rgb-Based Eye-Tracking For Large-Scale Human-Machine Applications, Brett Thaman, Trung Cao

Posters-at-the-Capitol

Gaze tracking has become an established technology that enables using an individual’s gaze as an input signal to support a variety of applications in the context of Human-Computer Interaction. Gaze tracking primarily relies on sensing devices such as infrared (IR) cameras. Nevertheless, in the recent years, several attempts have been realized at detecting gaze by acquiring and processing images acquired from standard RGB cameras. Nowadays, there are only a few publicly available open-source libraries and they have not been tested extensively. In this paper, we present the result of a comparative analysis that studied a commercial eye-tracking device using IR …

On The Synthesis Of Optimal Control Laws, Meir Pachter, Isaac E. Weintraub

Faculty Publications

In this paper we advocate for Isaacs' method for the solution of differential games to be applied to the solution of optimal control problems. To make the argument, the vehicle employed is Pontryagin's canonical optimal control example, which entails a double integrator plant. However, rather than controlling the state to the origin, we correctly require the end state to reach a terminal set that contains the origin in its interior. Indeed, in practice, it is required to control to a prescribed tolerance rather than reach a desired end state; achieving tight tolerances is expensive, and from a theoretical point of …

Enhanced Security Utilizing Side Channel Data Analysis, Michael Taylor

Computer Science and Engineering Theses and Dissertations

The physical state of a system is affected by the activities and processes in which it is tasked with carrying out. In the past there have been many instances where such physical changes have been exploited by bad actors in order to gain insight into the operational state and even the data being held on a system. This method of side channel exploitation is very often effective due to the relative difficulty of obfuscating activity on a physical level. However, in order to take advantage of side channel data streams one must have a detailed working knowledge of how a …

Synthetic Aperture Optical Imaging Interferometric Microscopy With Improved Image Quality, Preyom K. Dey

Electrical and Computer Engineering ETDs

The resolution limit of optical microscopy can be extended by using Imaging Interferometric Microscopy (IIM), which uses a low numerical aperture (NA) objective lens to achieve resolution equivalent to that of a high-NA objective lens with multiple sub-images. Along with the resolution enhancement challenge, IIM often suffers from poor image quality. In this dissertation, several image quality improvement methods are proposed and verified with simulation and experimental results. Next, techniques to extend the resolution limit of IIM to ≤ 100nm using a low-NA objective lens are demonstrated. An experimental technique of using a grating coupler on …

Intracavity Phase Interferometry Based Fiber Sensors, Luke Jameson Horstman

Optical Science and Engineering ETDs

Intracavity Phase Interferometry (IPI) is a detection technique that exploits the inherent sensitivity of a laser's frequency to the parameters of its cavity. Intracavity interferometry is orders of magnitude more sensitive than its extracavity alternatives. This dissertation improves on previous free-space proof-of-concept designs. By implementing the technique in fiber optics, using optical parametric oscillation, and investigating non-Hermitian quantum mechanics and dispersion tailoring enhancement techniques, IPI has become more applicable and sensitive. Ring and linear IPI configurations were realized in this work, both operating as bidirectional fiber optical parametric oscillators. The benefit of using externally pumped synchronous optical parametric oscillation is …

Short-Term Memory And Olfactory Signal Processing, Lijun Zhang

McKelvey School of Engineering Graduate Student Theses & Dissertations

Modern neural recording methodologies, including multi-electrode and optical recordings, allow us to monitor the large population of neurons with high temporal resolution. Such recordings provide rich datasets that are expected to understand better how information about the external world is internally represented and how these representations are altered over time. Achieving this goal requires the development of novel pattern recognition methods and/or the application of existing statistical methods in novel ways to gain insights into basic neural computational principles. In this dissertation, I will take this data-driven approach to dissect the role of short-term memory in olfactory signal processing in …

Numerical Investigations Of Logic Gates And Transistors In Quantum And Classical Information Processing, Anthony Corbin

McKelvey School of Engineering Graduate Student Theses & Dissertations

The development of numerical analysis techniques for electromagnetics and quantum mechanics problems has dramatically increased the rate of new discoveries. Propelled by the exponential growth of computers over the past decades, numerical software has brought the ability to reliably experiment with new ideas and predict new phenomena, even before the physical realizations of these ideas in the labs. This work will demonstrate the application of this capability by applying numerical analysis techniques to design and analyze new devices. First, a system of optical logic gates using a nonlinear metallodielectric grating is completely designed and simulated using numerical analysis. Second, the …

Inductor Free Methods For Breaking Dc Currents, Sudipta Sen

LSU Doctoral Dissertations

The current interruption in dc circuits is more difficult to achieve compared to the ac circuits because, unlike ac systems, dc circuits do not have the natural current zero-crossing. Presently there are three categories of basic dc breaker models namely mechanical, static, and hybrid dc breakers. As current power systems is moving more towards microgrids, DERs, Electric Vehicles (EVs), and with recent advancements in dc circuits, wide verities of dc power sources, and loads, dc breakers are very important in future system protection.

New alternate methods to break dc currents for low-voltage applications are proposed in this work. The proposed …

Single-Rail Adiabatic Logic For Energy-Efficient And Cpa-Resistant Cryptographic Circuit In Low-Frequency Medical Devices, Amit Degada, Himanshu Thapliyal

Electrical and Computer Engineering Graduate Research

Designing energy-efficient and secure cryptographic circuits in low-frequency medical devices are challenging due to low-energy requirements. Also, the conventional CMOS logic-based cryptographic circuits solutions in medical devices can be vulnerable to side-channel attacks (e.g. correlation power analysis (CPA)). In this article, we explored single-rail Clocked CMOS Adiabatic Logic (CCAL) to design an energy-efficient and secure cryptographic circuit for low-frequency medical devices. The performance of the CCAL logic-based circuits was checked with a power clock generator (2N2P-PCG) integrated into the design for the frequency range of 50 kHz to 250 kHz. The CCAL logic gates show an average of approximately 48% …

Defining And Detecting Toxicity On Social Media: Context And Knowledge Are Key, Amit Sheth, Valerie Shalin, Ugur Kursuncu

Publications

As the role of online platforms has become increasingly prominent for communication, toxic behaviors, such as cyberbullying and harassment, have been rampant in the last decade. On the other hand, online toxicity is multi-dimensional and sensitive in nature, which makes its detection challenging. As the impact of exposure to online toxicity can lead to serious implications for individuals and communities, reliable models and algorithms are required for detecting and understanding such communications. In this paper We define toxicity to provide a foundation drawing social theories. Then, we provide an approach that identifies multiple dimensions of toxicity and incorporates explicit knowledge …

Net-Zero Energy Districts And The Grid: An Energy-Economic Feasibility Case-Study Of The National Western Center In Denver, Co, Usa, Ben Saarloos, Jason C. Quinn

Faculty Work Comprehensive List

Given the enormous impact of buildings on energy consumption, it is important to continue the development of net-zero energy districts. Opportunities exist for energy efficiency and renewable energy on a district level that may not be feasible in individual buildings. Due to the intermittent nature of many renewable energy sources, net-zero energy districts are dependent on the energy grid. The novelty of this work is to quantify and optimize the economic cost and grid independence of a net-zero energy district using the National Western Center (NWC) in Denver, CO, USA as a case study. The NWC is a 100+ ha …

Machine Learning Approach To Stability Analysis Of Semiconductor Memory Element, Ravindra Thanniru, Gautam Kapila, Nibhrat Lohia

SMU Data Science Review

Memory stability analysis traditionally relied heavily on circuit simulation-based approaches that run Monte Carlo (MC) analysis over various manufacturing and use condition parameters. This paper researches application of Machine Learning approaches for memory element failure analysis which could mimic simulation-like accuracy and minimize the need for engineers to rely heavily on simulators for their validations. Both regressor and classifier algorithms are benchmarked for accuracy and recall scores. A high recall score implies fewer escapes of fails to field and is the metric of choice for comparing algorithm. The paper identifies that recall score in excess of 0.97 can be achieved …

Modeling Electric Energy Generation In Ercot During Extreme Weather Events And The Impact Renewable Energy Has On Grid Reliability, Adam R. Ruthford, Bivin Sadler

SMU Data Science Review

This paper shows the inadequacy of current grid backup supplies, their ongoing threat to grid reliability, and the increased risk of customer blackouts. This paper also examines reliability concerns caused by renewable energy sources under more normal operating conditions. This paper seeks to model the impacts of extreme weather on ERCOTs grid. Unusual weather patterns require that the electrical grid operates in conditions outside normal operating parameters. Electrical system demand can spike well above normal levels. At the same time, weather influences can change the operating envelope of electrical generation equipment. The ERCOT grid has changed from its’ traditional mix …