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Full-Text Articles in Engineering

Numerical Simulation Of Losses In Four-Way Pipe Junctions, Simon Barth May 2021

Numerical Simulation Of Losses In Four-Way Pipe Junctions, Simon Barth

All Graduate Theses and Dissertations

To design pipelines, engineers need to know how much energy the fluid in the pipe has at different locations in the pipe network. The energy the fluid has comes in the form of pressure, velocity, and elevation. As fluid travels through a pipe, it loses energy for many different reasons. Some of those reasons include friction between the fluid and the pipe wall, shear forces within the fluid, changes in flow direction, changes in elevation, or various pipe fittings like elbows, tee’s, valves, reducers, and expanders. Many of the causes of energy loss are well researched. One cause of ...


Towards A More Effective Bidirectional Lstm-Based Learning Model For Human-Bacterium Protein-Protein Interactions, Huaming Chen, Jun Shen, Lei Wang, Yaochu Jin Jan 2021

Towards A More Effective Bidirectional Lstm-Based Learning Model For Human-Bacterium Protein-Protein Interactions, Huaming Chen, Jun Shen, Lei Wang, Yaochu Jin

Faculty of Engineering and Information Sciences - Papers: Part B

The identification of protein-protein interaction (PPI) is one of the most important tasks to understand the biological functions and disease mechanisms. Although numerous databases of biological interactions have been published in debt to advanced high-throughput technology, the study of inter-species protein-protein interactions, especially between human and bacterium pathogens, remains an active yet challenging topic to harness computational models tackling the complex analysis and prediction tasks. In this paper, we comprehensively revisit the prediction task of human-bacterium protein-protein interactions (HB-PPI), which is a first ever endeavour to report an empirical evaluation in learning and predicting HB-PPI based on machine learning models ...


Evaluation Of Characteristics Of Wireless Sensor Networks With Analytical Modeling, Halim Khujamatov, Ernazar Reypnazarov, Doston Hasanov, Elaman Nurullaev, Shahzod Sobirov Dec 2020

Evaluation Of Characteristics Of Wireless Sensor Networks With Analytical Modeling, Halim Khujamatov, Ernazar Reypnazarov, Doston Hasanov, Elaman Nurullaev, Shahzod Sobirov

Bulletin of TUIT: Management and Communication Technologies

In this paper, a mathematical model of the operation process of the ZigBee standard wireless network for remote monitoring systems based on the Markov chain apparatus was developed. Using the model was evaluated of the operation process of the CSMA/CA algorithm of the MAC level of the IEEE 802.15.4 ZigBee standard. The peculiarity of this mathematical model is that it takes into account the level of loading of network elements and potential distortions in the transmitted packets as a result of the influence of interference. Using the developed mathematical model, the main characteristics of the network operation ...


Imitation Modeling The Discrete Communication Chanel In Matlab Stateflow On Basis Of Petrovich Model, Sh.Y. Djabborov, Sh.K. Ismailov, I.I. Omonov Nov 2020

Imitation Modeling The Discrete Communication Chanel In Matlab Stateflow On Basis Of Petrovich Model, Sh.Y. Djabborov, Sh.K. Ismailov, I.I. Omonov

Chemical Technology, Control and Management

The article defines the study of a discrete communication channel based on the Petrovich model, amending the faults and its simulation model using MATLAB software. In addition, to reduce the probability of multiple errors in data transmission, coding the discrete channel up to a fault tolerance level, to investigate the distribution of error-free transmission intervals in the discrete channel based on the Petrovich model, to construct the Petrovich model for the discrete channel, The State-flow diagram of Petrovich model is presented for the under research discrete channel. The processes meant by the article save real-time mode of technical engineers in ...


Theoretical Investigations On Electrocaloric Properties Of (111)-Oriented Pbmg1/3Nb2/3O3 Single Crystal, Mahmoud Aly Hamad Oct 2020

Theoretical Investigations On Electrocaloric Properties Of (111)-Oriented Pbmg1/3Nb2/3O3 Single Crystal, Mahmoud Aly Hamad

Journal of Advanced Ceramics

The electrocaloric (EC) effect accompanied with the ferroelectric to paraelectric phase transition in (111)-oriented PbMg1/3Nb2/3O3 (PMN) is investigated. It is shown that the largest change ΔT is 0.37 K in 3 kV/cm electric field shift near the Curie temperature of 221 K; that is, the cooling ΔT per unit field (MV/m) is 1.23×10-6 m·K/V. This value is significantly larger, and comparable with the value of 0.254×10-6 m·K/V for PbZr0.95Ti0.05O3 thin film under ...


Theoretical Work On Magnetocaloric Effect In La0.75Ca0.25Mno3, Mahmoud Aly Hamad Oct 2020

Theoretical Work On Magnetocaloric Effect In La0.75Ca0.25Mno3, Mahmoud Aly Hamad

Journal of Advanced Ceramics

In this work, a phenomenological model is applied to describe the magnetocaloric effect for the La0.75Ca0.25MnO3 system near a second-order phase transition from a ferromagnetic to a paramagnetic state. Based on this model, it can predict the values of the magnetocaloric properties from calculation of magnetization as a function of temperature under different external magnetic fields. The magnetic entropy change reaches a peak of about 5.39 J/(kg·K) at 257 K upon 4 T applied field variation. The ∆SM distribution is much more uniform than that of gadolinium, which is ...


Potential Hydrodynamic Origin Of Frictional Transients In Sliding Mesothelial Tissues, Stephen H. Loring, James P. Butler Oct 2020

Potential Hydrodynamic Origin Of Frictional Transients In Sliding Mesothelial Tissues, Stephen H. Loring, James P. Butler

Friction

Steady-state and transient variations in frictional force observed in tribological experiments of mesothelial tissues sliding in lubricant were analyzed with a mathematical model to test the hypothesis that such phenomena are manifestations of elastohydrodynamic lubrication and, importantly, do not require physical contact between the sliding surfaces. The model incorporates three phenomena characteristic of elastohydrodynamic lubrication: thinning of the liquid layer between sliding surfaces under a normal load (“squeeze-out”), thickening of the liquid layer due to hydrodynamic pumping, and smoothing of the elastic surfaces caused by hydrodynamic pressure gradients. Observations in soft mesothelial tissues sliding in lubricant showed variations in steady ...


A Novel Path Loss Forecast Model To Support Digital Twins For High Frequency Communications Networks, James Marvin Taylor Jr Jul 2020

A Novel Path Loss Forecast Model To Support Digital Twins For High Frequency Communications Networks, James Marvin Taylor Jr

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

The need for long-distance High Frequency (HF) communications in the 3-30 MHz frequency range seemed to diminish at the end of the 20th century with the advent of space-based communications and the spread of fiber optic-connected digital networks. Renewed interest in HF has emerged as an enabler for operations in austere locations and for its ability to serve as a redundant link when space-based and terrestrial communication channels fail. Communications system designers can create a “digital twin” system to explore the operational advantages and constraints of the new capability. Existing wireless channel models can adequately simulate communication channel conditions with ...


Research Properties Of Solving Problems Of Parametric Optimization, Dilnoz Tulkunovna Muhamediyeva Jun 2020

Research Properties Of Solving Problems Of Parametric Optimization, Dilnoz Tulkunovna Muhamediyeva

Chemical Technology, Control and Management

A model of parametric optimization with fuzzy initial information is constructed. The conditions and areas of application of the main methods of the theory of fuzzy sets in studies of parametric optimization are determined. A connection is established between the stability of parametric optimization problems and fuzzy optimization problems. An algorithm for solving problems by the method of parametric programming is developed for fuzzy given initial information. The admissible region of the parametric programming problem and the value of its objective function at each point of this region depend on the parameter t. A description of the method for solving ...


Experimental Research Methodology For The Crack Resistance Of Large-Panel Buildings In Seismic Areas, Nigmat Baxramovich Shaumarov, Ulugbek Xakimovich Abdullayev May 2020

Experimental Research Methodology For The Crack Resistance Of Large-Panel Buildings In Seismic Areas, Nigmat Baxramovich Shaumarov, Ulugbek Xakimovich Abdullayev

Journal of Tashkent Institute of Railway Engineers

The experience of the Tashkent, Spitak, Kyrgyz and Kamchatka earthquakes of recent years has led to the conclusion that there is a sufficient good seismic resistance of large-panel buildings with a narrow step of transverse load-bearing walls. One of the distinguishing structural features of buildings is considered to be the overlapping of individual multi-hollow panels with their support on special cantilevered outlets along the lateral surfaces of the transverse walls. Elements of the outer walls were made of expanded clay concrete with a compressive strength of about 200 kg / cm2. All structures were reinforced with flat welded frames made of ...


Discrete Vortex Modeling Of Aerodynamic Flutter Of A Flat Plate With Damped Oscillations, Emma Chao May 2020

Discrete Vortex Modeling Of Aerodynamic Flutter Of A Flat Plate With Damped Oscillations, Emma Chao

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aerodynamic flutter is the unstable oscillation of a body caused by the interaction of aerodynamic forces, structural elasticity, and inertial effects induced by vortex shedding. Current models of this phenomenon require finite element analysis and extensive computational power and processing time. The purpose of this study was to develop and validate a program that is faster and more efficient than existing approaches by using the discrete vortex method (DVM). By reducing the complexities of flutter to the shedding of vortices in an inviscid model of a two-dimensional flat plate with a torsional spring constant at its center, this phenomenon can ...


Emergency Eye Simulation Model, Gavin L. Warrington, Christopher Forsyth, Lexus Morris, Natalie Ledezma May 2020

Emergency Eye Simulation Model, Gavin L. Warrington, Christopher Forsyth, Lexus Morris, Natalie Ledezma

Chancellor’s Honors Program Projects

No abstract provided.


Thermal Chemical Energy Storage, William Miller, Samuel Swayne, Jonathan West, John Davis, James Mcbroom, Tennessee Bryant May 2020

Thermal Chemical Energy Storage, William Miller, Samuel Swayne, Jonathan West, John Davis, James Mcbroom, Tennessee Bryant

Chancellor’s Honors Program Projects

No abstract provided.


To The Conclusion Of The Variational Equation Of Motion Of Shell Structures Supported By Frames And Stringers, Farkhod Erkinovich Abdukadirov Mar 2020

To The Conclusion Of The Variational Equation Of Motion Of Shell Structures Supported By Frames And Stringers, Farkhod Erkinovich Abdukadirov

Journal of Tashkent Institute of Railway Engineers

In this article is given the construction of the variational equation of motion of the shell structure supported by frames and stringers. Using the Hamilton - Ostrogradsky variational principle, systems of differential equations of motion of shell elements are obtained.


Neuro-Fuzzy Modeling For Predictive Control Systems With Complex Technological Processes And Production, Yusupbekov Nodirbek, Shukhrat Gulyamov, Malika Doshchanova Feb 2020

Neuro-Fuzzy Modeling For Predictive Control Systems With Complex Technological Processes And Production, Yusupbekov Nodirbek, Shukhrat Gulyamov, Malika Doshchanova

Chemical Technology, Control and Management

The paper implements a modification of a fuzzy neural network, which is suitable for predictive control purposes. Adaptation of a multidimensional programmable controller based on a neural algorithm for the back propagation of forecasting errors is proposed, as well as neural parametric identification of a fuzzy mathematical model of complex technological processes and production based on experimental data and expert estimates.


Importance Of Extracellular Dna In The Fate And Transport Of Antibiotic Resistance Genes Downstream Of A Wastewater Treatment Plant, Kaoru Ikuma, Chris R. Rehmann Feb 2020

Importance Of Extracellular Dna In The Fate And Transport Of Antibiotic Resistance Genes Downstream Of A Wastewater Treatment Plant, Kaoru Ikuma, Chris R. Rehmann

Civil, Construction and Environmental Engineering Publications

A model is developed to account for antibiotic resistance genes (ARGs) as both intracellular DNA (iDNA) and extracellular DNA (eDNA) in predicting the fate and transport of ARGs in receiving waters downstream of wastewater treatment plants (WWTPs). eDNA can contribute to iDNA concentrations of ARGs through horizontal gene transfer (i.e., transformation); however, the prevalence of eDNA and its effects have not been addressed in previous field studies and predictive models. The present model tracks eDNA and iDNA in both the water column and the sediment, and it includes physical, chemical, and biological processes. It also provides a framework for ...


Establecimiento De Dos Cultivos Frijol Y Arracacha Como Modelo De Diversificación De La Producción Agrícola Familiar En El Municipio De Guavatá Santander, Brayan Orlando Ariza Velasco Jan 2020

Establecimiento De Dos Cultivos Frijol Y Arracacha Como Modelo De Diversificación De La Producción Agrícola Familiar En El Municipio De Guavatá Santander, Brayan Orlando Ariza Velasco

Ingeniería Agronómica

El proyecto Productivo se llevó a cabo en el municipio de Guavatá Santander mediante el apoyo de Universidad de La Salle proyecto Utopía. El componente de ingeniería agronómica para el cual se establecieron dos cultivos, Fríjol (Phaseolus Vulgaris) y Arracacha (Arracacia xanthorrhiza) como modelo de diversificación de la producción agrícola familiar en el municipio; este componente fue exitoso ya que se realizó un manejo técnico adecuado se dio a conocer esta alternativa en la región y se obtuvieron altos rendimientos. El componente de investigación el cual tuvo como objetivo analizar los sistemas actuales de producción de guayaba del municipio de ...


Hybrid Translation And Language Model For Micro Learning Material Recommendation, Jiayin Lin Jan 2020

Hybrid Translation And Language Model For Micro Learning Material Recommendation, Jiayin Lin

Faculty of Engineering and Information Sciences - Papers: Part A

As an emerging pedagogy, micro learning aims to make use of people’s fragmented spare time and provide personalized online learning service, for example, by pushing fragmented knowledge to specific learners. In the context of big data, the recommender system is the key factor for realizing the online personalization service, which significantly determines what information will be fmally accessed by the target learners. In the education discipline, due to the pedagogical requirements and the domain characteristics, ranking recommended learning materials is essential for maintaining the outcome of the massive learning scenario. However, many widely used recommendation strategies in other domains ...


Fórmula Sintética Para El Cálculo De La Reactancia De Dispersión En Transformadores De Núcleo Arrollado, Darwin Felipe Alcócer Torres, Cristian David Bermúdez Gutiérrez Jan 2020

Fórmula Sintética Para El Cálculo De La Reactancia De Dispersión En Transformadores De Núcleo Arrollado, Darwin Felipe Alcócer Torres, Cristian David Bermúdez Gutiérrez

Ingeniería Eléctrica

En este trabajo se presenta una fórmula sintética para el cálculo de la reactancia de dispersión en transformadores de núcleo arrollado. La fórmula propuesta en esta tesis tomó como base inicial la fórmula obtenida en el trabajo de maestría de Castañeda Hernández (2019). Los resultados calculados con la fórmula sintética mostraron una exactitud promedio superior a los obtenidos con la fórmula propuesta en Castañeda Hernández (2019). La fórmula sintética se obtuvo incluyendo más grados de libertad a la fórmula de Castañeda y realizando una regresión no lineal para determinar el valor de los grados de libertad. La regresión no lineal ...


Deep Sequence Labelling Model For Information Extraction In Micro Learning Service, Jiayin Lin, Zhexuan Zhou, Geng Sun, Jun Shen, David Pritchard, Tingru Cui, Dongming Xu, Li Li, Ghassan Beydoun Jan 2020

Deep Sequence Labelling Model For Information Extraction In Micro Learning Service, Jiayin Lin, Zhexuan Zhou, Geng Sun, Jun Shen, David Pritchard, Tingru Cui, Dongming Xu, Li Li, Ghassan Beydoun

Faculty of Engineering and Information Sciences - Papers: Part B

Micro learning aims to assist users in making good use of smaller chunks of spare time and provides an effective online learning service. However, to provide such personalized online services on the Web, a number of information overload challenges persist. Effectively and precisely mining and extracting valuable information from massive and redundant information is a significant preprocessing procedure for personalizing online services. In this study, we propose a deep sequence labelling model for locating, extracting, and classifying key information for micro learning services. The proposed model is general and combines the advantages of different types of classical neural network. Early ...


A New Data Driven Long-Term Solar Yield Analysis Model Of Photovoltaic Power Plants, Biplob Ray, Rakibuzzaman Shah, Md Rabiul Islam, Syed Islam Jan 2020

A New Data Driven Long-Term Solar Yield Analysis Model Of Photovoltaic Power Plants, Biplob Ray, Rakibuzzaman Shah, Md Rabiul Islam, Syed Islam

Faculty of Engineering and Information Sciences - Papers: Part B

Historical data offers a wealth of knowledge to the users. However, often restrictively mammoth that the information cannot be fully extracted, synthesized, and analyzed efficiently for an application such as the forecasting of variable generator outputs. Moreover, the accuracy of the prediction method is vital. Therefore, a trade-off between accuracy and efficacy is required for the data-driven energy forecasting method. It has been identified that the hybrid approach may outperform the individual technique in minimizing the error while challenging to synthesize. A hybrid deep learning-based method is proposed for the output prediction of the solar photovoltaic systems (i.e. proposed ...


Diseño De Un Modelo Para La Gestión De La Innovación En Wm Wireless & Mobile Sas En Bogotá, Manuel Sebastián Bernal Díaz, Silvana Soto Ocampo Jan 2020

Diseño De Un Modelo Para La Gestión De La Innovación En Wm Wireless & Mobile Sas En Bogotá, Manuel Sebastián Bernal Díaz, Silvana Soto Ocampo

Ingeniería Industrial

En un mercado globalizado, donde las empresas cada vez son más competitivas y productivas, la innovación es una de las herramientas para mantenerse vigente, ya que ofrecer un amplio portafolio de productos y servicios lleva a las organizaciones a competir con base al costo, entorpeciendo él desarrollo normal de la economía, por lo que estas deben salir de los commodities hacia los océanos azules (Mauborgne & Kim, 2016). Es por esto que el Gobierno Nacional promueve nuevas políticas, planes de gobierno, incentivos y manuales de buenas prácticas, entre otros, para que, desde los diferentes organismos, como la Cámara de Comercio de ...


A Novel Monte Carlo-Based Neural Network Model For Electricity Load Forecasting, Binbin Yong, Zijian Xu, Jun Shen, Huaming Chen, Jianqing Wu, Fucun Li, Qingguo Zhou Jan 2020

A Novel Monte Carlo-Based Neural Network Model For Electricity Load Forecasting, Binbin Yong, Zijian Xu, Jun Shen, Huaming Chen, Jianqing Wu, Fucun Li, Qingguo Zhou

Faculty of Engineering and Information Sciences - Papers: Part B

The ongoing rapid growth of electricity over the past few decades greatly promotes the necessity of accurate electricity load forecasting. However, despite a great number of studies, electricity load forecasting is still an enormous challenge for its complexity. Recently, the developments of machine learning technologies in different research areas have demonstrated its great advantages. General Vector Machine (GVM) is a new machine learning model, which has been proven very effective in time series prediction. In this article, we firstly review the basic concepts and implementation of GVM. Then we apply it in electricity load forecasting, which is based on the ...


Model Predictive Control For A New Magnetic Linked Multilevel Inverter To Integrate Solar Photovoltaic Systems With The Power Grids, A M. Mahfuz-Ur-Rahman, Md Rabiul Islam, Kashem M. Muttaqi, Danny Sutanto Jan 2020

Model Predictive Control For A New Magnetic Linked Multilevel Inverter To Integrate Solar Photovoltaic Systems With The Power Grids, A M. Mahfuz-Ur-Rahman, Md Rabiul Islam, Kashem M. Muttaqi, Danny Sutanto

Faculty of Engineering and Information Sciences - Papers: Part B

The multilevel inverters are becoming increasingly popular for use in the grid integration of wind and photovoltaic (PV) power plants due to their higher voltage handling capability and the better output power quality. There are several types of multilevel inverters that have been proposed in the literature; among them the active neutral point clamp (ANPC) multilevel inverters have been drawing significant attention specially for solving the problems with other multilevel inverters. However, with the increase of number of levels, the ANPC requires more electronic switches and flying capacitors, by which the complexity and the cost increases. In this paper, an ...


Miniature Photogrammetry Rig, Alec Geither, Sean Weber Jan 2020

Miniature Photogrammetry Rig, Alec Geither, Sean Weber

Williams Honors College, Honors Research Projects

Photogrammetry is a process that accurately gathers measurements from multiple photographs, capturing all sides and angles of the object. As long as a point is visible in at least three different photographs, its position can be triangulated accurately relative to each other point on the model. This process has a diverse range of applications, from surveying land to developing virtual training systems for professional athletes. One interesting application for photogrammetry is to create highly accurate electronic three-dimensional models from a series of photographs. We intend to build a miniature photogrammetry rig for use at the University of Akron.


Theoretical Study Of The Process Of Issue Of Small Weed Impurities From A Flap Of A Cotton, B.M. Mardonov, X.S. Usmanov, F.N. Sirojiddinov Dec 2019

Theoretical Study Of The Process Of Issue Of Small Weed Impurities From A Flap Of A Cotton, B.M. Mardonov, X.S. Usmanov, F.N. Sirojiddinov

Textile Journal of Uzbekistan

It is known that the process of cleaning weed impurities from cotton is complex and, theoretically, this process has not been adequately studied. The reason for this is that the forces that bind weed impurities and fibers have not been studied. Applied modern power circuits are insufficient to classify this process. Therefore, it is advisable to study this process using other methods. The article presents the patterns obtained as a result of theoretical researches, describing the processes of effective separation of weed impurities from cotton. As a result of the movement of the cotton mass on the outer side of ...


A Kinetic And Thermodynamic Model Of Ethylene Dichloride Pyrolysis., Travis J Czechorski Nov 2019

A Kinetic And Thermodynamic Model Of Ethylene Dichloride Pyrolysis., Travis J Czechorski

Electronic Theses and Dissertations

Ethylene dichloride (EDC) is a precursor for the production of vinyl chloride (VCM) which is subsequently polymerized to form polyvinyl chloride (PVC). To convert EDC to VCM, EDC undergoes a pyrolysis process in the absence of oxygen at temperatures exceeding 500C. However, process yields are limited by the uncontrolled production of side-products that can degrade the quality of PVC and poison the reactor. Thus, tight process controls and costly separations guided by heuristics and plant operator experience are used to optimize EDC pyrolysis. To improve the process, I have programed a kinetic model of EDC pyrolysis based upon estimations of ...


Modelling The Addition Of Limestone In Cement Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer Sep 2019

Modelling The Addition Of Limestone In Cement Using Hydcem, Niall Holmes, Denis Kelliher, Mark Tyrer

Conference papers

Hydration models can aid in the prediction, understanding and description of hydration behaviour over time as the move towards more sustainable cements continues.

HYDCEM is a new model to predict the phase assemblage, degree of hydration and heat release over time for cements undergoing hydration for any w/c ratio and curing temperatures up to 450C. HYDCEM, written in MATLAB, complements more sophisticated thermodynamic models by predicting these properties over time using user-friendly inputs within one code. A number of functions and methods based on up to date cement hydration behaviour from the literature are hard-wired into the code along ...


Model Based Analysis Of The Accuracy And Precision Of Auscultatory Blood Pressure Measurements In Patients With Atrial Fibrillation, Charles F. Babbs Sep 2019

Model Based Analysis Of The Accuracy And Precision Of Auscultatory Blood Pressure Measurements In Patients With Atrial Fibrillation, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

Accurate measurement of blood pressure in the presence of atrial fibrillation remains an open problem. The present study combines the techniques of stochastic mathematical modeling with physiological models of the systemic circulation, cuff, and arm (1) to explore mechanisms underlying both the lack of accuracy and the lack of precision in cuff-based arterial pressure measurements during atrial fibrillation and (2) to develop strategies to correct for errors. Both the cardiovascular system and the measurement technique are described using mathematics, including both numerical techniques and analytical probability theory. Preliminary results with numerical models suggested that, despite variability, average systolic pressures tend ...


On The Construction Of Canonical Systems Of Equations For Cylindrical And Spherical Shell Structures, A. Abdusattarov, F.E. Abduqodirov Aug 2019

On The Construction Of Canonical Systems Of Equations For Cylindrical And Spherical Shell Structures, A. Abdusattarov, F.E. Abduqodirov

Journal of Tashkent Institute of Railway Engineers

In this article is given the construction of canonical systems, the equation of motion for axisymmetric shell structures, as well as for cylindrical and spherical shells