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Articles 29611 - 29640 of 196033

Full-Text Articles in Engineering

A Multistep Fusion Matcher Approach For Large Scale Latent Fingerprint/Palmprint Recognition, İsmai̇l Kilinç, Yusuf Oğuzhan Artan, Emre Başeski̇ Mar 2023

A Multistep Fusion Matcher Approach For Large Scale Latent Fingerprint/Palmprint Recognition, İsmai̇l Kilinç, Yusuf Oğuzhan Artan, Emre Başeski̇

Turkish Journal of Electrical Engineering and Computer Sciences

Latent fingerprints are ubiquitously used as forensic evidence by law enforcement agencies in solving crimes. However, due to deformations and artifacts within latent fingerprint images, performance of the automated latent recognition systems are far from desired levels. A basic matcher specifically designed for clean fingerprints using a minutiae-based matching algorithm can have high speed and accuracy in a sensor-to-sensor matching task, but low accuracy in matching latent prints, due to scale, rotation and quality differences between latent and sensor images. In this study, we propose a unique multistep fusion matcher (FM) on top of a base matcher that would utilize …


Reconstructing Dynamic Human Shapes From Sparse Silhouettes Via Latent Space Optimization Of Parametric Shape Models, Kanika Singla, Parma Nand Mar 2023

Reconstructing Dynamic Human Shapes From Sparse Silhouettes Via Latent Space Optimization Of Parametric Shape Models, Kanika Singla, Parma Nand

Turkish Journal of Electrical Engineering and Computer Sciences

The problem of dynamic 3D reconstruction has gained popularity over the last few years with most approaches relying on data driven learning and optimization methods. However this is quite a challenging task because of the need for tracking different features in both space and time?that too of deformable objects-where such robust tracking may not always be possible. A common way to better ground the problem is by using some forms of regularizations primarily on the shape representations. Over the years, mesh-based linear blend skinning models have been the standard for fitting templates of humans to the observed time series data …


Analysis And Usage Of Natural Language Features In Success Prediction Of Legislative Testimonies, Marine Cossoul Mar 2023

Analysis And Usage Of Natural Language Features In Success Prediction Of Legislative Testimonies, Marine Cossoul

Master's Theses

Committee meetings are a fundamental part of the legislative process in which
constituents, lobbyists, and legislators alike can speak on proposed bills at the
local and state level. Oftentimes, unspoken “rules” or standards are at play in
political processes that can influence the trajectory of a bill, leaving constituents
without a political background at an inherent disadvantage when engaging with
the legislative process. The work done in this thesis aims to explore the extent to
which the language and phraseology of a general public testimony can influence a
vote, and examine how this information can be used to promote civic …


Highway To The Comfort Zone: History Of The Psychrometric Chart, Eric Teitelbaum, Clayton Miller, Forrest Meggers Mar 2023

Highway To The Comfort Zone: History Of The Psychrometric Chart, Eric Teitelbaum, Clayton Miller, Forrest Meggers

Research Collection College of Integrative Studies

The psychrometric chart is the most common data visualization technique for the designers of thermal comfort systems worldwide. From its humble roots as means of expressing the characteristics of air in building systems design, the use of the chart has grown to include the representation of the zones of human thermal comfort according to both conventional and adaptive models. In this paper, we present an extensive history of this development and the fallacies with representing comfort simply as a box that sometimes moves on the chart. The origins of the link between refrigeration control and comfort control are examined through …


Reinforcement Learning Framework For The Unreal Engine, Justin B. Wheeler Mar 2023

Reinforcement Learning Framework For The Unreal Engine, Justin B. Wheeler

Master's Theses

This dissertation addresses the need for using machine learning-based methods rather than traditional rule-based methods for controlling non-playable characters (NPCs). The goal of the Reinforcement Learning Framework for the Unreal Engine is to enable game development studios to create, train, and more easily implement smarter, more compelling AI characters in major video game releases. The framework contains three distinct software libraries: an Unreal Engine reinforcement learning library whose purpose is to enable Unreal Engine levels to act as reinforcement learning environments, a python library which provides convenient abstractions and implementations to the reinforcement learning process, and a flexible connection system …


Using Switchable Solvents For Enhanced Biodiesel Production, Eyad Abdel Rahman Sowan Mar 2023

Using Switchable Solvents For Enhanced Biodiesel Production, Eyad Abdel Rahman Sowan

Theses

This thesis presents a sustainable approach to biodiesel production using in-situ technology for direct conversion of microalgae-to-biodiesel. The proposed method operates on wet, untreated microalgae, thereby eliminating the cost/energy intensive drying and cell disruption steps. Owing to their favorable properties, the use of enzymes, specifically lipase, as a catalyst for the process was suggested over acid/base catalysts. However, the high cost of the enzyme necessitates its reuse at sustained activity for the process to be economically feasible. The use of non-toxic green solvents, such as switchable solvents, as an alternative to conventional organic solvents was a significant challenge for the …


A Modified Space Vector Modulation Based Rotor Flux Oriented Control Of Six-Phase Asymmetrical Induction Motor Drive, Krunal Shah, Rakesh Maurya Mar 2023

A Modified Space Vector Modulation Based Rotor Flux Oriented Control Of Six-Phase Asymmetrical Induction Motor Drive, Krunal Shah, Rakesh Maurya

Turkish Journal of Electrical Engineering and Computer Sciences

In view of the attractive features like improved torque density, reduction torque pulsation, superior fault tolerance, reduced power rating of voltage source converter, and sterling noise characteristics of six-phase asymmetrical induction motor (SPAIM) as compared to its three-phase counterpart, the SPAIM is considered for the study. In this paper, mathematical modelling of SPAIM is carried out in the synchronous reference frame and then indirect rotor field-oriented control (IRFOC) of SPAIM using a modified carrier wave-based space vector modulation (SVM) scheme is developed. A Simulink model of the proposed system configuration is developed and a simulation study is carried out. In …


Spayk: An Environment For Spiking Neural Network Simulation, Aykut Görkem Gelen, Ayten Atasoy Mar 2023

Spayk: An Environment For Spiking Neural Network Simulation, Aykut Görkem Gelen, Ayten Atasoy

Turkish Journal of Electrical Engineering and Computer Sciences

In research areas such as mobile robotics and computer vision, energy and computational efficiency have become critical. This has greatly increased interest in high-efficiency neuromorphic hardware and spiking neural networks. Because neuromorphic hardware is not yet widely available, spiking neural network studies are conducted by simulations. There are numerous simulators available today, each designed for a specific purpose. In this paper, a novel and open source package (SPAYK) for simulating spiking neural networks is presented. SPAYK has been proposed to speed up spiking neural network research. In the majority of simulators, networks are expressed with differential equations and require advanced …


Defense Industrial Base Mergers And Acquisitions In The Post-Cold War Era, Corey D. Mack Mar 2023

Defense Industrial Base Mergers And Acquisitions In The Post-Cold War Era, Corey D. Mack

Theses and Dissertations

The United States Department of Defense (DoD) relies on prime contractors for weapon system development, acquisition, and sustainability, but the increased consolidation of the Defense Industrial Base (DIB) through mergers and acquisitions (M&A) has raised concerns over reduced competition. This research consists of two studies. The first reviews existing literature to identify factors behind the DIB's increased M&A activity since the 1990s, such as DoD budget cuts and market structure. The second study examines the relationship between a prime contractor's financial health and M&A spending, finding a significant relationship between efficiency and M&A spending. Policymakers can use this information to …


Optimization Of Co2 Huff-N-Puff In Unconventional Reservoirs With A Focus On Pore Confinement Effects, Fluid Types, And Completion Parameters, Aaditya Khanal, Md Fahim Shahriar Feb 2023

Optimization Of Co2 Huff-N-Puff In Unconventional Reservoirs With A Focus On Pore Confinement Effects, Fluid Types, And Completion Parameters, Aaditya Khanal, Md Fahim Shahriar

Jasper Department of Chemical Engineering Faculty Publications and Presentations

The cyclic injection of CO2, referred to as the huff-n-puff (HnP) method, is an attractive option to improve oil recovery from unconventional reservoirs. This study evaluates the optimization of the CO2 HnP method and provides insight into the aspects of CO2 sequestration for unconventional reservoirs. Furthermore, this study also examines the impact of nanopore confinement, fluid composition, injection solvent, diffusivity parameters, and fracture properties on the long-term recovery factor. The results from over 500 independent simulations showed that the optimal recovery is obtained for the puff-to-huff ratio of around 2.73 with a soak period of fewer than 2.7 days. After …


Separation Axioms In Neutrosophic Topological Spaces, Sudeep Dey, Gautam Chandra Ray Feb 2023

Separation Axioms In Neutrosophic Topological Spaces, Sudeep Dey, Gautam Chandra Ray

Neutrosophic Systems with Applications

In this article, we first establish some results based on single-valued neutrosophic sets. Next, we define a subspace topology in a neutrosophic topological space and investigate some properties. We then define the neutrosophic T0, T1, T2-spaces and study their various properties, offering adequate examples.


Recent Advances In Anode Materials Of Solid Oxide Electrolysis Cells, Geng Zou, Wei-Cheng Feng, Yue-Feng Song, Guo-Xiong Wang Feb 2023

Recent Advances In Anode Materials Of Solid Oxide Electrolysis Cells, Geng Zou, Wei-Cheng Feng, Yue-Feng Song, Guo-Xiong Wang

Journal of Electrochemistry

Solid oxide electrolysis cell (SOEC) as an electrochemical energy conversion device has attracted increasing attention due to its large current density, high Faradaic efficiency and energy efficiency. Oxygen evolution reaction at the anode, a four-electron transfer process, is an important half-reaction for SOEC, which contributes to the main polarization resistance and consumes most electric energy during the electrolysis process. Hence, designing anode materials with high activity and stability is crucial for the performance improvement and practical application of SOEC. Recently, some advances have been made in the development of high-performance anode. In the current review, the mechanisms for CO2 …


Anodic Electrocatalysis Of Glycerol Oxidation For Hybrid Alkali/Acid Electrolytic Hydrogen Generation, Xin Feng, Bo-Wen Liu, Ke-Xin Guo, Lin-Feng Fan, Gen-Xiang Wang, Su-Qin Ci, Zhen-Hai Wen Feb 2023

Anodic Electrocatalysis Of Glycerol Oxidation For Hybrid Alkali/Acid Electrolytic Hydrogen Generation, Xin Feng, Bo-Wen Liu, Ke-Xin Guo, Lin-Feng Fan, Gen-Xiang Wang, Su-Qin Ci, Zhen-Hai Wen

Journal of Electrochemistry

Electrolytic hydrogen production is heavily restricted by high-energy consumption majorly due to the relatively high potential of anodic oxygen evolution reaction (OER). Development of OER-alternative reaction at the anode has been recently proposed as a promising pathway to address the associated issues. In this work, we report a hybrid acid/alkali dual-electrolyte electrolyzer by coupling acidic hydrogen evolution reaction (HER) using commercial Pt/C cathode with alkaline Electrocatalytic glycerol oxidation (GOR) which is implemented by developing a nickel foam (NF) supporting Co3O4 nanosheets anode that shows low overpotential and high selectivity toward GOR for formate production. The hybrid acid/alkali …


Procedural Model Of The Monitoring System, Fayzullajon Botirov Feb 2023

Procedural Model Of The Monitoring System, Fayzullajon Botirov

Chemical Technology, Control and Management

This article discusses the process of monitoring information security incidents and factors affecting the effectiveness of monitoring. A procedural model of the functioning of the information security incident monitoring system is constructed, based on the study of its structure, the principles of operation of individual components and literature data, the analysis of individual stages.


Synchronization Of The Training Of Specialists In The Automation Of Technological Processes In Accordance With The Dynamics Of The Taxonomy Of Learning Goals, Yusuf Shodievich Avazov, Kamola Abdullaeva Feb 2023

Synchronization Of The Training Of Specialists In The Automation Of Technological Processes In Accordance With The Dynamics Of The Taxonomy Of Learning Goals, Yusuf Shodievich Avazov, Kamola Abdullaeva

Chemical Technology, Control and Management

Changes in the characteristics of modern ones, reflecting them as the "digital generation", inevitably necessitate electronic interactive, mobile and mixed, machine learning, especially in the field of automation and control of technological processes and production. As a consequence of reflecting these realities, there have been parallel changes in the taxonomy of learning objectives - from the classical to the revised rethought and digital.

In order to study the problem of synchronizing the training of future specialists in the field of automation and control of technological processes and production and funny knowledge in accordance with the dynamics of the taxonomy of …


Algorithmic Methods For Developing The Structure Of A Thyristor Electric Drive For Mining Machines, N.R Yusupbekov, O.A. Jumaev, S.S. Turaev Feb 2023

Algorithmic Methods For Developing The Structure Of A Thyristor Electric Drive For Mining Machines, N.R Yusupbekov, O.A. Jumaev, S.S. Turaev

Chemical Technology, Control and Management

The article discusses the creation of algorithmic structures and the development of digital control systems for electric drives of mine-lifting machines, provides some concepts for creating digital control systems using thyristor converters. The analysis of the static volt-ampere characteristics of the thyristor is given, some calculations of the circuits and circuits of the thyristor converter (TP) corresponding to the different modes of operation of the TP are given, and also, based on the synthesis of the dynamic properties and characteristics of the thyristor, an algorithmic structure of the model of the thyristor converter is proposed.


Method For Solving The Kinematics Inverse Problem For Moving Along A Trajectory Objects (As An Example Of Assembly Industrial Robots), Oripjon Olimovich Zaripov, Dildora Usmonovna Sevinova Feb 2023

Method For Solving The Kinematics Inverse Problem For Moving Along A Trajectory Objects (As An Example Of Assembly Industrial Robots), Oripjon Olimovich Zaripov, Dildora Usmonovna Sevinova

Chemical Technology, Control and Management

The task of performing a technological operation in kinematic calculation of industrial robots and determining various kinematic parameters describing the efficiency of robots is solved. Among them, one of the urgent problems based on the analysis of the entire kinematics of the assembly industrial robot is the problem of solving the inverse problem of the kinematics of the manipulator positions, that is, the problem of determining the relative parameters that change the coordinates of the gripper according to the given position. The article presents a scheme that allows solving the inverse kinematics problem of an industrial robot manipulator moving in …


Research Of Three-Phases Current’S Transducers Of Filter-Compensation Devices For Control Reactive Power’S Consumption Of Asynchronous Motor, Ilkhomjon Khakimovich Siddikov, Dilyorbek Karimjonov Doniyorbek O'G'Li -, Abdumutal Abdikarimovich Abdigapirov Feb 2023

Research Of Three-Phases Current’S Transducers Of Filter-Compensation Devices For Control Reactive Power’S Consumption Of Asynchronous Motor, Ilkhomjon Khakimovich Siddikov, Dilyorbek Karimjonov Doniyorbek O'G'Li -, Abdumutal Abdikarimovich Abdigapirov

Chemical Technology, Control and Management

In the article given materials of developing of three-phase electromagnetic current transducers of reactive power, using with asynchronous motor, methods connecting of two sensing element, series, parallel and differential and loops suitable for each phase, dynamic characteristics of output signals of three-phase electromagnetic current transducers asynchronous motor.

On the basis of modern calculation and design complexes are of great importance in the research variable sizes of three-phase current electromagnetic transducers of filter-compensation devices of reactive power of asynchronous motors. Presented mathematical model of research of electrical, electromagnetic and magnetic elements of electromagnetic current transducers in the …


Modeling Of The Process Of Measuring Conversion Of The Flow Of Liquid And Gaseous Media By The Method Of Variable Pressure Drop, Shukhrat Manapovich Gulyamov, Elbek Elmirza O'G'Li Ortiqov Feb 2023

Modeling Of The Process Of Measuring Conversion Of The Flow Of Liquid And Gaseous Media By The Method Of Variable Pressure Drop, Shukhrat Manapovich Gulyamov, Elbek Elmirza O'G'Li Ortiqov

Chemical Technology, Control and Management

On the basis of material and heat balances, taking into account the initial and boundary conditions, a mathematical model of the process of measuring the transformation of liquid and gaseous technological media by the method of variable pressure drop is constructed. The analysis of the results of studying the influence of non-stationary flows of a controlled medium on the uncertainty of the results of measuring the flow rate of liquids and gaseous mixtures with a changing hydrodynamic structure of the flow of a controlled medium is performed. A comparative analysis of the calculated and experimental transient processes in the measuring …


Virtual Potassium Chloride Analyzer In The System Of Advanced Control Of Potash Fertilizer Production Processes, Umidjon Ruziev, Jahongir Sherboyevich Bekqulov Feb 2023

Virtual Potassium Chloride Analyzer In The System Of Advanced Control Of Potash Fertilizer Production Processes, Umidjon Ruziev, Jahongir Sherboyevich Bekqulov

Chemical Technology, Control and Management

It is proposed to include virtual instrumental quality analyzers of potash fertilizers in the composition of the advanced (advanced) management system. The structure of the virtual analyzer is substantiated using mathematical models of the technological process of drying potassium chloride in its composition. Based on the results of fuzzy clustering, the parameters of the modes of the technological process of drying potassium chloride are determined.


Model For Calculating The Static Characteristics Of Hydraulic Systems Of Hydro Technical Buildings, Mirkhalil Ismailov, Dong Zhang, Farkhod Kasimov Feb 2023

Model For Calculating The Static Characteristics Of Hydraulic Systems Of Hydro Technical Buildings, Mirkhalil Ismailov, Dong Zhang, Farkhod Kasimov

Chemical Technology, Control and Management

Hydraulic mechanisms that actuate flat gates, widely used in hydraulic structures, are studied as hydraulic actuators of the system. Their static mathematical models are developed using an integrated methodology with a hydraulic pump, inlet and suction pipes, and internal and external resistance factors. Unlike existing mathematical models, the model developed in this paper allows a detailed description of the characteristics of hydraulic drives due to the fact that pressure losses in the throttle, regulator, and power amplifier, as well as local resistances in hydraulic pipelines, are taken into account.


Towards Lean Manufacturing In Developing Countries: Research Gaps And Directions In Tanzania, Francis D. Sinkamba Feb 2023

Towards Lean Manufacturing In Developing Countries: Research Gaps And Directions In Tanzania, Francis D. Sinkamba

Tanzania Journal of Engineering and Technology (TJET)

In the current knowledge-driven economy, many industries across the globe are forced to adopt manufacturing technologies such as lean manufacturing to remain competitive in the globalized world. Despite the increase in lean manufacturing implementations, the adoption rate in Tanzania is very low and estimated to be 8 percent. Likewise, the sustainability of lean manufacturing tools and practices is still questionable, which shows the need to develop lean maturity models. To date, several lean maturity models have been developed but there is ARTICLE INFO Submitted: July 5, 2022 Revised: Sept. 28, 2022 Presented: Oct. 20, 2022 a lack of maturity models …


Design Of International Airport Hybrid Renewable Energy System, Aviti Thadei Mushi Feb 2023

Design Of International Airport Hybrid Renewable Energy System, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

This paper presents the design and simulation of a hybrid renewable energy system utilizing solar and wind energy sources with a backup generator. The demand for reliable electric energy in support of investments in large social and economic development activities such as airport operations has been an agenda worldwide. In Tanzania, Mwanza International Airport (MIA) expects to consume about 18 MVA of electric power annually to support its operations for the next 25 years. About 78-80% of the world's commercial energy comes from fossil fuels. Non-renewable fuels and other negative effects contribute to global warming through greenhouse gas emissions and …


Extraction And Characterization Of Collagen From Cattle Horns For Potential Wound Healing, Yeriko Halson Feb 2023

Extraction And Characterization Of Collagen From Cattle Horns For Potential Wound Healing, Yeriko Halson

Tanzania Journal of Engineering and Technology (TJET)

The need for bandages and gauze for wound dressing and healing is inevitable due to the high increase in accidents. Most of the material used for the production of bandages and gauzes for wound healing are from non-renewable synthetic material. The sustainability of non renewable resources is at jeopardy due to the health and associated environmental impact. Consequently, the use of naturally occurring and biodegradable material is a promising solution to the sustainability challenges of synthetic material. In this paper, the extraction of collagen films from cattle horns for potential wound healing is reported. Collagen was extracted from cattle horns …


Current And Future Trends Of Construction Project Performance Models: A Review, Method Mtana Feb 2023

Current And Future Trends Of Construction Project Performance Models: A Review, Method Mtana

Tanzania Journal of Engineering and Technology (TJET)

The construction industry (CI) has experienced outstanding growth and contributed to economic growth for many countries, with enormous foreign investments that require quality projects. High pressure to reduce the construction cost and time commonly put the industry at risk of lower quality and safety of the construction facilities. Like many other developing countries, Tanzania needs more stringent quality control measures in the construction sector to contribute positively to sustainable growth. This study thus reviews current and future trends in construction industry performance in Tanzania. The literature review on construction projects (CPs) performance is based on information on time overruns from …


Studying Dielectric Losses Of Serially Combined Silicone Rubber And Epoxy Resin, Aviti Thadei Mushi Feb 2023

Studying Dielectric Losses Of Serially Combined Silicone Rubber And Epoxy Resin, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

High voltage outdoor insulation systems are conventionally ceramics and glass with several advantages, such as proven in the field, excellent dielectric properties, durability, and long life. However, they are heavy, attract vandals and break easily, and they can lose their dielectric properties easily when subjected to high voltage transients, arcing, and surges. To curb this, polymer insulators are used because they have excellent dielectric properties, such as those of ceramics and glass, with the added advantages that they do not break easily and recover their lost dielectric properties after any electrical transients. Therefore, this paper investigates the dielectric properties of …


Factors Influencing Total Productive Maintenance Implementation For Thermal Generation Plants, Ismail W. R. Taifa Dr Feb 2023

Factors Influencing Total Productive Maintenance Implementation For Thermal Generation Plants, Ismail W. R. Taifa Dr

Tanzania Journal of Engineering and Technology (TJET)

This study accepts that the technical and administrative factors can amplify effective total productive maintenance (TPM) implementation at thermal generation plants. It is noted that there is a limited number of studies that have attempted to understand the subject of TPM implementation in the energy sector. Noting this shortcoming, the authors thought it crucial to generate empirical evidence on the factors influencing effective TPM implementation for thermal generation plants, with evidence from gas-fired plants. A sample of 88 respondents was selected and consulted. Data were collected through questionnaires and analyzed quantitatively by inferential statistics and qualitatively through thematic analysis using …


Towards The Development Of A Framework For Assessing Organizational Governance Maturity For Technical Audit Of Public Works, George Haule Feb 2023

Towards The Development Of A Framework For Assessing Organizational Governance Maturity For Technical Audit Of Public Works, George Haule

Tanzania Journal of Engineering and Technology (TJET)

The quality of the audit work and its products is often associated with the organizational maturity of the audit function. The absence of a well-defined organizational maturity for an audit function leads to poor quality of audit work or products and ineffective audit function. The lack of a framework for measuring governance maturity was identified as a major deterrent factor to the attainment of quality audit work. Measuring the governance maturity of the technical audit of public works is challenging due to the absence of a maturity framework that fits its needs. The noted shortcomings include: (a) existing maturity frameworks …


Crack Detection In An Aluminium Oxide Grinding Wheel By Impact Hammer Tests, Yubin Lee, David Turcic, Dan Danks, Chien Wern Feb 2023

Crack Detection In An Aluminium Oxide Grinding Wheel By Impact Hammer Tests, Yubin Lee, David Turcic, Dan Danks, Chien Wern

Mechanical and Materials Engineering Faculty Publications and Presentations

Grinding is widely used as the last step of the manufacturing process when a good surface finish and precise dimensional tolerances are required. However, if the grinding wheels have cracks, they may lead to a hazardous working environment and produce poor tolerance in machined products. Therefore, grinding wheels should be inspected for cracks before being mounted onto the machine. In this study, a novel method of finding possible internal cracks in the aluminium oxide grinding wheel will be explored by examining the natural frequency and displacement of wheels using an impact hammer testing method. Grinding wheels were cracked into two …


Analysis Of Vegetable Oil Refining Technology, Elyor Samadov Feb 2023

Analysis Of Vegetable Oil Refining Technology, Elyor Samadov

Chemical Technology, Control and Management

Innovative technologies for refining vegetable oils are presented, as well as the qualitative characteristics of raw vegetable oils obtained by extraction and mechanical methods. A general review of the chemical composition and impurities of vegetable oils resulting from the reaction between glycerol and fatty acids is carried out, and a brief review of the study to determine the effect of refining on biologically active components.

The analytical review is devoted to a comparative comparison of two types of refining - chemical and physical refining.