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Articles 271 - 300 of 11113
Full-Text Articles in Engineering
Numerical Modeling Of Badminton Shuttlecock Trajectories, Lola G. Torres, Cassandra Pumphrey, Jadyn Peterson, Domenic Barsotti
Numerical Modeling Of Badminton Shuttlecock Trajectories, Lola G. Torres, Cassandra Pumphrey, Jadyn Peterson, Domenic Barsotti
Discovery Day - Daytona Beach
The Trajectory of a badminton Shuttlecock can vary significantly when compared to a classic projectile motion, primarily due to aerodynamic drag. This project aims to model the flight of the shuttlecock using Newton's second law for gravitational and drag related forces, resulting in a nonlinear system of a first order differential equation. The given parameters include the shuttlecock mass, cross-sectional area, air density, as well as the drag coefficient, determining the overall magnitude of the drag force. The resulting initial value problem is solved numerically using a multitude of Runge_Kutta methods to compare the accuracy and stability across different computational …
Motion With Air Resistance, Gauge Mccain, Jacob Bealefeld, Francesca Wise
Motion With Air Resistance, Gauge Mccain, Jacob Bealefeld, Francesca Wise
Discovery Day - Daytona Beach
The motion of objects moving through air is influenced not only by gravity but also by air resistance, which affects the speed and acceleration of the object over time. This project examines the motion of a falling object by modeling it with an ordinary differential equation that accounts for both gravitational force and a resistive drag force proportional to velocity. Using Newton’s Second Law, a first-order differential equation is derived to describe how the velocity of the object changes as it falls. The solution of this equation demonstrates how the velocity increases initially and gradually approaches a constant value known …
Engineering Path Trajectories With Gravitational Fields, Eliane Dean, Aidan Hart, Isabel Noot, Nathan Browning, Valeria Villazon Fito
Engineering Path Trajectories With Gravitational Fields, Eliane Dean, Aidan Hart, Isabel Noot, Nathan Browning, Valeria Villazon Fito
Discovery Day - Daytona Beach
This project explores how vector calculus concepts play a role in aerospace engineering though spacecraft trajectory design. In particular, the notion of vector fields is used to model the gravitational force, whose work done is expressed through line integrals. By taking the curl of the gravitational field and showing it is zero, the field is recognised as conservative, implying that the work done by gravity is path independent. This property is conceptually linked to gravitational potential energy and the principle of energy conservation. The results are then applied to spacecraft motion, where engineers use energy-base methods to determine efficient trajectories …
Modelling Quadcopter Thrust And Torque Using Lu-Decomposition, Diya Patil
Modelling Quadcopter Thrust And Torque Using Lu-Decomposition, Diya Patil
Discovery Day - Daytona Beach
3 & 4 motor systems have been in the world of aviation in many different forms as the field grows and evolves. To understand the complexities of an Unmanned Aerial Vehicle (UAV) and its stability, assessing the amount of thrust put into each motor can help generate the torque produced despite factors such as multidirectional movement. While a UAV does this multiple times a second, producing a simplified version of this calculation can aid in simpler models simulating UAV movement. Due to the popularity of the quadcopter drone, a simple algorithm depicting thrust through each spinning motor can aid in …
Simulations Of Phugoid Motion Of Jal 123, Dereth J J. Drake Scheuermann
Simulations Of Phugoid Motion Of Jal 123, Dereth J J. Drake Scheuermann
Georgia Journal of Science
Airplanes rely on a balance between the four forces of flight: lift, weight, thrust, and drag. If these forces are balanced, the airplane will remain stable. However, if structurally or systematically compromised, the motion can rapidly become unstable. In the aviation industry, mistakes in repairs and aircraft design can lead to accidents causing the loss of life in some cases. In this article, we will be analyzing what happened 70 Japan Airlines flight 123 and how the flight’s motion deteriorated due to a defective repair. More specifically, we will discuss the aerodynamic effects of phugoid motion and how it developed …
Feasibility And Performance Of Aerogravity Assists For Ceres Missions, Divinaa E. Burder
Feasibility And Performance Of Aerogravity Assists For Ceres Missions, Divinaa E. Burder
International Journal of Aviation, Aeronautics, and Aerospace
This work investigates the feasibility and performance of aerogravity assist (AGA) maneuvers for missions to Ceres, with emphasis on both interplanetary trajectory design and atmospheric flight dynamics. AGAs provide substantially greater turning capability than pure gravity assists by exploiting aerodynamic lift during atmospheric passes, thereby enabling greater heliocentric energy changes than pure gravity assists. To quantify these benefits, this study integrates a broad interplanetary trajectory search with high-fidelity atmospheric performance modeling. Candidate trajectories for launch years 2030–2050 are generated for multiple inner-planet encounter sequences using vehicles with lift-to-drag ratios (L/D) between 1 and 7. Atmospheric flight segments are simulated using …
Accelerating Rans Cfd Convergence For Bluff Body Flows Using Surface-Vorticity Panel Solver Initialization, Trisha Babu
Accelerating Rans Cfd Convergence For Bluff Body Flows Using Surface-Vorticity Panel Solver Initialization, Trisha Babu
All Graduate Reports and Creative Projects, Fall 2023 to Present
Reynolds-Averaged Navier--Stokes (RANS) simulations are widely used for predicting aerodynamic performance in engineering applications but often require substantial computational time to achieve convergence, particularly for bluff-body flows characterized by large-scale separation and wake formation. Improving the initialization of CFD simulations offers a practical approach for reducing computational cost without modifying the underlying numerical algorithms. This study investigates the use of a surface-vorticity panel solver (FlightStream) to generate physically informed velocity fields for initializing steady RANS simulations in STAR-CCM+.
Two canonical bluff-body geometries are considered: a sphere at a Reynolds number of 5 X 105 and an isolated cube at …
Toward Risk-Informed Design Of Supercooling Heat Exchangers: Statistical Inference And Experimental Investigation Of Heterogeneous Ice Nucleation, Daniel B. Gardner
Toward Risk-Informed Design Of Supercooling Heat Exchangers: Statistical Inference And Experimental Investigation Of Heterogeneous Ice Nucleation, Daniel B. Gardner
All Graduate Theses and Dissertations, Fall 2023 to Present
Ice-based cooling storage systems can reduce electricity costs and grid strain by making ice during off-peak hours and using it for air conditioning during the day. One promising design works by chilling water below its freezing point as it flows through a heat exchanger, then allowing it to freeze in a separate storage tank. The challenge is that the chilled water can freeze prematurely inside the heat exchanger itself, blocking the flow and shutting the system down. Preventing this unwanted freezing requires understanding how and where ice begins to form on surfaces, a process called nucleation.
This dissertation investigates ice …
A Cfd-Dem Framework For Characterizing Nanoparticle Adhesion Effects On Creeping-Flow Permeability In Composite Manufacturing, Gavin Stoker
A Cfd-Dem Framework For Characterizing Nanoparticle Adhesion Effects On Creeping-Flow Permeability In Composite Manufacturing, Gavin Stoker
All Graduate Theses and Dissertations, Fall 2023 to Present
Modern aircraft, spacecraft, and high-performance vehicles are increasingly built from composite materials, engineered combinations of plastics and fibers that are lighter and stronger than traditional metals. Researchers are now pushing these materials further by mixing in microscopic particles thousands of times smaller than a human hair, called nanoparticles, to make them even tougher and more resistant to damage. The challenge is getting those nanoparticles distributed evenly. During manufacturing, liquid plastic resin is pumped through a network of tightly packed fibers, carrying the nanoparticles along with it. But nanoparticles tend to clump together and stick to surfaces as they travel, clogging …
Theory, Implementation, And Practical Applications Of A Modern Parabolized Navier-Stokes Code, Logan B. Freeman
Theory, Implementation, And Practical Applications Of A Modern Parabolized Navier-Stokes Code, Logan B. Freeman
All Graduate Theses and Dissertations, Fall 2023 to Present
The Parabolized Navier-Stokes (PNS) method is a specialized computational approach for solving the equations that govern fluid flowing faster than the speed of sound, known as supersonic flow. By leveraging unique physical properties of supersonic environments—specifically that information cannot travel upstream—this method allows for significantly more efficient calculations than traditional approaches. Supersonic flows are important for many military and civilian applications including hypersonic weapons, high-speed passenger aircraft, and reentry. This thesis provides a comprehensive review of the two-dimensional PNS formulation, detailing the mathematical derivation and its practical implementation for solving flow problems. Through performance analysis and error assessment, this research …
Simulation Of Hypersonic Conditions In A Lab-Scale Environment Using A Hybrid Rocket With Nitrogen Cooling, Joshua R. Sorenson
Simulation Of Hypersonic Conditions In A Lab-Scale Environment Using A Hybrid Rocket With Nitrogen Cooling, Joshua R. Sorenson
All Graduate Theses and Dissertations, Fall 2023 to Present
Developing hypersonic vehicles requires testing under extreme heat, airflow, and pressure. Traditional facilities like shock tunnels and arc-heated wind tunnels are costly and slow to set up. This thesis proposes a simpler, low-cost method using a small-scale hybrid rocket motor as a gas generator. The rocket’s hot exhaust is directed onto the front edge of a scaled-down model that represents the nose of a hypersonic vehicle. This creates a realistic flow that matches both the intense heat energy and the pushing force experienced in high-altitude hypersonic flight. The setup allows easy measurement of motor performance, surface pressures, leading-edge temperatures, and …
Machine Learning For Predictive Energy And Emissions Modeling Of Vehicles And Power Grids In The United States, S M Tanvir Faysal Alam Chowdhoury
Machine Learning For Predictive Energy And Emissions Modeling Of Vehicles And Power Grids In The United States, S M Tanvir Faysal Alam Chowdhoury
Dissertations
The environmental benefits of electric vehicle (EV) adoption depend on more than replacing internal combustion engine vehicles with electric powertrains. EV adoption reshapes electricity demand, interacts with regional generation mixes, and influences travel behavior and congestion, creating a coupled transportation-energy system in which vehicle and power-plant emissions must be evaluated together. This dissertation develops machine-learning frameworks for predicting energy consumption and emissions from vehicles and power grids under rising EV adoption. The first component forecasts grid emissions from EV charging. Using simulation data from NREL's Cambium database, a Prophet-based time-series framework predicts carbon dioxide, nitrous oxide, and methane emission rates …
Powered Parachute Vehicle For Crew Transportation On Mars, Louis J. Spier
Powered Parachute Vehicle For Crew Transportation On Mars, Louis J. Spier
Beyond: Undergraduate Research Journal
To support possible future human presence on Mars where bases are likely to be spread apart, aerial vehicles could be used to transport crew and cargo between them. Designing and operating such a vehicle is very challenging because of the low atmospheric density on Mars compared to Earth, the logistics involved with transporting it to Mars, and the infrastructure necessary to operate it. This study discusses the problems involved with designing, building, and operating fixed-wing and powered parachute aircraft on Mars and presents a concept involving a powered parachute vehicle utilizing an inflatable parachute wing that can be packed together …
Global Time-Resolved Measurements Of Inlet/Isolator Unstart Induced By Mass Injection, Andrew N. Bustard, Benjamin L. Bemis, Aaron Marques, Matthew J. Zahr, Thomas J. Juliano
Global Time-Resolved Measurements Of Inlet/Isolator Unstart Induced By Mass Injection, Andrew N. Bustard, Benjamin L. Bemis, Aaron Marques, Matthew J. Zahr, Thomas J. Juliano
Publications
The inner surface pressure of an axisymmetric inlet/isolator model was measured using anodized-aluminum pressure-sensitive paint (PSP) viewing through cast acrylic. Temperaturesensitive paint was utilized to correct for the PSP’s temperature sensitivity. The model was tested under Mach 5.7 flow at 𝑹𝒆 = 7.1 ×106 /m under conventional noise conditions. Transverse jet injection with jet-to-inlet mass-flow ratios up to 0.8 was used to induce unstart in the inlet/isolator. Background-oriented schlieren visualization of the inlet shocks was collected simultaneously with the PSP to determine when the inlet unstarted. Computational fluid dynamics results were used to determine off-wall flow structures and quantify approach …
Effect Of Solid Particle Size And Density On Incipient Motion In A Turbulent Boundary Layer, Robert Bryan
Effect Of Solid Particle Size And Density On Incipient Motion In A Turbulent Boundary Layer, Robert Bryan
Doctoral Dissertations and Master's Theses
Wind-blown sand and other instances of solid particles mobilized and suspended in gaseous turbulent boundary layers (TBLs) are seen in a wide variety of engineering contexts. An experimental framework was developed to study the incipient particle motion driven by external forcing within a turbulent boundary layer, which is provided by an airfoil section oscillating in the free-steam flow, resulting in a periodic disturbance in the near-wall region through production of synthetic large-scale structures at a fixed frequency. The incoming unsteady carrier-phase eddies were measured with a hot-film sensor upstream of a particle bed, and the particle motion was captured by …
Building China’S Space Station Intellectual Property Protection System: Strategic Demands, International Rule Competition, And Institutional Pathways, Xiao Youdan, Bing Xiao, Yi Zheng, Xianghui Liu
Building China’S Space Station Intellectual Property Protection System: Strategic Demands, International Rule Competition, And Institutional Pathways, Xiao Youdan, Bing Xiao, Yi Zheng, Xianghui Liu
Bulletin of Chinese Academy of Sciences (Chinese Version)
As China’s space station transitions into its application and development phase, on-orbit research outputs are entering a period of concentrated yield. The protection of space station intellectual property (IP) has evolved from a theoretical proposition into a pressing institutional demand. For decades, developed economies, notably the United States and European nations, have dominated the development of international space IP rules. Their core approach extends the traditional principle of territoriality through “legal fiction”, establishing jurisdiction based on the “State of registry’s jurisdiction”—that is, treating space objects as extensions of the registering State’s territory, thereby extending the reach of domestic IP law …
From Resource Mapping To Mechanism Identification: A Lunar Tethered-Satellite Exploration System And China’S Strategic Opportunities, Wei Yong, Zhiping He, Yanchu Yang, Ke Wang, Junqiang Zhu
From Resource Mapping To Mechanism Identification: A Lunar Tethered-Satellite Exploration System And China’S Strategic Opportunities, Wei Yong, Zhiping He, Yanchu Yang, Ke Wang, Junqiang Zhu
Bulletin of Chinese Academy of Sciences (Chinese Version)
Lunar exploration is undergoing a paradigm shift from resource mapping to mechanism identification. Key processes, such as the modulation of volatiles by magnetic anomalies and the contribution of Earth wind to surface hydration, require strictly synchronized observations of magnetic-field gradients, particle fluxes, spectrally detected volatiles, and subsurface hydrogen within the same spatiotemporal window. However, a still-unfilled “near-lunar-surface intermediate layer” gap exists between conventional single-spacecraft orbiters and landed rovers: the capability for multi-altitude, multi-parameter, strictly synchronized process observations. A tethered dual-satellite system, consisting of a main satellite and a subsatellite connected by a 5–10 km short tether, naturally provides a dual-altitude …
Technological Advancements Of Hybrid Rocket Engines For Sustainable And Competitive In-Space Propulsion Applications, Ryan J. Thibaudeau, Stephen A. Whitmore, Jared Coen, Joshua Sorenson, Logan Mecham, Ava Wilkey
Technological Advancements Of Hybrid Rocket Engines For Sustainable And Competitive In-Space Propulsion Applications, Ryan J. Thibaudeau, Stephen A. Whitmore, Jared Coen, Joshua Sorenson, Logan Mecham, Ava Wilkey
Mechanical and Aerospace Engineering Student Publications and Presentations
Hybrid rocket engines (HREs), which pair a fluid oxidizer with a solid fuel, offer safety and handling advantages, can reduce environmental impact relative to selected legacy systems, and are capable of deep throttling and restart, making them strong candidates for “green” in-space propulsion applications. However, until very recently, there has not been any flight heritage of an HRE used in a spaceflight mission. Over the past decade, the Propulsion Research Laboratory at Utah State University (PRL-USU) has matured a portfolio of HRE technologies—low-energy arc ignition, digital throttling, additively manufactured sustainable fuels, the Nytrox green oxidizer, and electroplated thruster assemblies—that together …
Assessing Computer Vision Based Conflict Detection In Uas Traffic Monitoring Under Secure Communication Constraints, Fadjimata Issoufou Anaroua
Assessing Computer Vision Based Conflict Detection In Uas Traffic Monitoring Under Secure Communication Constraints, Fadjimata Issoufou Anaroua
Doctoral Dissertations and Master's Theses
The rapid growth of Unmanned Aircraft Systems (UAS) and Advanced Air Mobility (AAM) is creating a new low-altitude airspace ecosystem where drones, air taxis, service suppliers, communication networks, sensors, and ground-based monitoring systems must work together safely. Within this ecosystem, UAS Traffic Management (UTM) is expected to provide a digital framework for coordinating operations beyond traditional air traffic control. However, reliable integration also requires resilient monitoring methods that can detect non-cooperative aircraft, protect communication links, and maintain timely situational awareness under real-world constraints.
This dissertation examines how computer vision can support cooperative monitoring systems such as Remote ID and ADS-B …
Gust-Induced Aerodynamic Performance In Insects' Forward Flapping Flight, Arash Farsani, Ori Stearns, Gal Ribak, Roi Gurka
Gust-Induced Aerodynamic Performance In Insects' Forward Flapping Flight, Arash Farsani, Ori Stearns, Gal Ribak, Roi Gurka
Physics and Engineering Science
Flapping-wing flight is inherently unsteady, where atmospheric gusts can substantially degrade the aerodynamic performance when their characteristic time scales are comparable to the wingbeat period. This study presents a numerical investigation and time–frequency characterization of gust-induced aerodynamic response of flapping wings of varying size, inspired by the flight of a longhorn beetle, Batocera rufomaculata. Geometrically similar wings spanning the biological range were simulated in forward flight under identical prescribed kinematics and a transient frontal gust with a smoothly ramped profile. Three-dimensional unsteady Reynolds-averaged Navier–Stokes simulations using the shear stress transport k–ω turbulence model were performed to resolve the instantaneous pressure …
3d Semi-Analytical Thermo-Elasto-Plastic Model For Additive Manufacturing, Tao Liu, Ming C. Leu, Edward C. Kinzel, Chinedum Okwudire
3d Semi-Analytical Thermo-Elasto-Plastic Model For Additive Manufacturing, Tao Liu, Ming C. Leu, Edward C. Kinzel, Chinedum Okwudire
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In additive manufacturing (AM), stress field drives distortion and warping and promotes delamination and cracking. Fast, accurate stress prediction is therefore essential for AM process planning and control, including real-time adaptive control, AM digital twins, data-driven and physics-driven workflows. However, spot-wise thermo-elasto-plastic finite element method (FEM) are often too slow for design iteration or real time use. Existing semi-analytical thermo-elasto-plastic approaches achieve high speed but are largely limited to 2D. In this paper, a full 3D semi-analytical thermo-elasto-plastic model for AM is built. The method uses a spot-wise analytical thermal field as the load and computes displacements and stresses via …
Investigation Of Energy Efficiency Of An Autonomous Mobile Photovoltaic-Thermal (Pv/T) System With A Polycarbonate Absorber, Sanjar Kodir Ugli Shoguchkarov, Anvar Rakhmat Ugli Rakhmatov, Rushana Husen Kizi Abdullaeva, Orazbek Maratbay Ugli Temirbaev
Investigation Of Energy Efficiency Of An Autonomous Mobile Photovoltaic-Thermal (Pv/T) System With A Polycarbonate Absorber, Sanjar Kodir Ugli Shoguchkarov, Anvar Rakhmat Ugli Rakhmatov, Rushana Husen Kizi Abdullaeva, Orazbek Maratbay Ugli Temirbaev
Technical science and innovation
This study analyzes the enhancement of energy efficiency in photovoltaic-thermal (PV/T) systems, which enable the simultaneous generation of electrical and thermal energy from solar radiation. The research focus is an autonomous mobile unit based on multi-channel polycarbonate heat collectors with a hydraulic diameter of 8 mm, characterized by their lightweight nature and superior corrosion resistance compared to conventional metal absorbers. Experimental investigations were conducted at the solar testing field of the Physical-Technical Institute of the Academy of Sciences of Uzbekistan under extreme continental climatic conditions to determine the system's stable thermophysical indicators. The results demonstrated that active water cooling using …
Use Of New Improved Methods For Assessing The Engineering-Geological Characteristics Of Deposits By Depth (Using The Example Of The Akba Deposit)., Elboy Shavkatovich Qurbonov Salom, Abduboqib Djalilovich Karimov, Yokub Yarash Ugli Isomiddinov
Use Of New Improved Methods For Assessing The Engineering-Geological Characteristics Of Deposits By Depth (Using The Example Of The Akba Deposit)., Elboy Shavkatovich Qurbonov Salom, Abduboqib Djalilovich Karimov, Yokub Yarash Ugli Isomiddinov
Technical science and innovation
The article examines the fracturing and filtration properties of rocks in boreholes, rock outcrops, and underground mine workings at the Akba gold deposit. Based on the results of hydrogeological and engineering-geological studies, methods that fully meet modern requirements were used, the values of the RMR rating of rocks and the indicators of the qualitative content of RQD rocks, as well as the intervals of their changes, were studied, as a result of which it became possible to quickly and accurately assess the strength state of the rock mass of the deposit territory by depth and area.
Modeling Of Terpolymerization Kinetics And Determination Of Reactivity Ratios In The Tdma–Styrene–Maleic Anhydride System, Shohrux Boboxon Ugli Mavlonov, Sadriddin Fayzullayevich Fozilov
Modeling Of Terpolymerization Kinetics And Determination Of Reactivity Ratios In The Tdma–Styrene–Maleic Anhydride System, Shohrux Boboxon Ugli Mavlonov, Sadriddin Fayzullayevich Fozilov
Technical science and innovation
In this study, the kinetics of terpolymerization, compositional evolution, and monomer reactivity ratios in the TDMA–styrene–maleic anhydride system were comprehensively investigated. Increasing the initiator concentration from 16.8×10⁻⁶ to 51.3×10⁻⁶ mol•L⁻¹ led to an increase in conversion from 6.4% to 15.2% and reaction rate from 4.075×10⁻⁶ to 8.965×10⁻⁶ mol•L⁻¹•s⁻¹. At low conversion (Xw≈0.02–0.09), the terpolymer composition remained close to the initial feed, although deviations due to differences in monomer reactivity were observed. With increasing conversion, some systems exhibited stable composition (±0.02), while others showed compositional drift (increase of MA fraction from 0.50 to 0.70). The determined reactivity ratios (rTDMA/St≈0.99; rSt/TDMA≈1.62; rTDMA/MA≈2.02; …
Development Of An Optimal Composition Of A Composite Solvent For Asphalt–Resin–Paraffin Deposits, Gulmira Abduvaliyevna Tadjiyeva, Xasan Irgashevich Kadirov, Shaxnoza Abduvaliyevna Tadjiyeva, Fazliddin Zokir Ugli Murodullayev, Bekmurodjon Baxtiyorjon Ugli Raximjonov
Development Of An Optimal Composition Of A Composite Solvent For Asphalt–Resin–Paraffin Deposits, Gulmira Abduvaliyevna Tadjiyeva, Xasan Irgashevich Kadirov, Shaxnoza Abduvaliyevna Tadjiyeva, Fazliddin Zokir Ugli Murodullayev, Bekmurodjon Baxtiyorjon Ugli Raximjonov
Technical science and innovation
A solvent formulation composed of aromatic hydrocarbons of the C9 fraction and aliphatic alcohols in a 1:1 ratio, supplemented with 1–3 wt.% of a nonionic surfactant, has been developed. The proposed composition demonstrates more than a twofold increase in dissolving and washing efficiency toward paraffin-type asphaltene–resin deposits. Furthermore, the solvent system exhibits pronounced depressant–dispersant properties with respect to paraffin-containing organic deposits. Although numerous investigations have addressed the development of technologies for removing organic deposits in oilfield equipment—primarily focusing on specific aspects of eliminating or preventing asphaltene–resin–paraffin deposits (ARPD) in wells—limited attention has been given to the design of integrated approaches. …
Technology For Obtaining Aliphatic Amines Based On Liquid By-Products Of Polymerization Processes, Kamila Sabirbaevna Allanazarova, Ulugbek Komiljonovich Urinov
Technology For Obtaining Aliphatic Amines Based On Liquid By-Products Of Polymerization Processes, Kamila Sabirbaevna Allanazarova, Ulugbek Komiljonovich Urinov
Technical science and innovation
Polymerization processes generate considerable amounts of liquid secondary by-products, which are often underutilized despite their significant chemical potential. Addressing the need for sustainable resource use, this study aims to develop a technological method for converting these by-products into valuable aliphatic amines. The experimental approach involved the pre-treatment of liquid polymerization by-products through fractional distillation to isolate C3–C10 fractions, followed by catalytic amination using Raney nickel under controlled temperature (160°C) and pressure (12 atm) conditions. Analytical methods including gas chromatography-mass spectrometry (GC-MS) and Fourier-transform infrared spectroscopy (FTIR) were employed to characterize the reaction products. The results demonstrated the successful formation of …
Optimization Of Aluminum Coating Deposition Parameters To Enhance The Performance Of Automotive Headlamps, Gulirano Saidakhmedova, Giovanni Maizza
Optimization Of Aluminum Coating Deposition Parameters To Enhance The Performance Of Automotive Headlamps, Gulirano Saidakhmedova, Giovanni Maizza
Technical science and innovation
The paper investigates the influence of the optical characteristics of functional coatings applied to automotive reflectors on vehicle active safety parameters, with a focus on the range and intensity of road illumination. The study examines the mathematical relationship between the maximum luminous intensity of a headlamp, the object detection distance, and the reflection coefficient of an aluminium layer deposited via vacuum thermal evaporation. The main factors driving the degradation of surface reflectivity (including oxidation, thermal degradation of the base coat, and surface roughness) are analysed. It is demonstrated that a decrease in the reflection coefficient during operation directly impairs the …
Adaptive – Compositional Method For Coordinating Subsystems At Different Levels In Hierarchical Control Systems, Husan Zakirovich Igamberdiyev, Uktam Farxodovich Mamirov Mr, Inomjon Ilxom Ugli Abdukaxxarov Mr
Adaptive – Compositional Method For Coordinating Subsystems At Different Levels In Hierarchical Control Systems, Husan Zakirovich Igamberdiyev, Uktam Farxodovich Mamirov Mr, Inomjon Ilxom Ugli Abdukaxxarov Mr
Technical science and innovation
This paper examines the problem of synthesizing algorithms for the composition of subsystems at various levels within complex hierarchical control systems under conditions of uncertainty and resource constraints. It is demonstrated that classical composition algorithms, which rely on the intersection of admissible sets and the use of local optimality criteria, suffer from several significant drawbacks. These include a combinatorial increase in complexity, dependence on the expert selection of parameters, and limited applicability in dynamic environments. To overcome these shortcomings, an adaptive-compositional method is proposed. This method is based on the dynamic recalculation of coordination parameters, the integration of model predictive …
Calculation Of The Basic Parameters Of The Hybrid Power Plant (Hpu) On The Spark Car, Rustam Raximovich Tillahodjaev, Jamoliddin Pardaboy Ugli Turdiev
Calculation Of The Basic Parameters Of The Hybrid Power Plant (Hpu) On The Spark Car, Rustam Raximovich Tillahodjaev, Jamoliddin Pardaboy Ugli Turdiev
Technical science and innovation
This article presents one of the effective ways to improve fuel efficiency and reduce emissions of toxic substances, the use of internal combustion engines with the use of an electric drive in their designs. In recent years, two directions in the development of cars with electromechanical drives have been clearly identified, the first is the creation of a pure electric car, the second is the development of an electromechanical drive with a combined (hybrid) power plant. Due to the lack of efficient energy storage available for mass production, pure electric vehicles have relatively low mileage on a single charge. This …
Experimental Study Of An Automotive Cooling System With A Mechatronic Control System, Avaz Israilovich Yangibayev
Experimental Study Of An Automotive Cooling System With A Mechatronic Control System, Avaz Israilovich Yangibayev
Technical science and innovation
This article presents the results of experimental investigations of a passenger car engine cooling system equipped with a mechatronic control system. The experiments were conducted on an intelligent hardware-software laboratory test bench developed using original components of a Chevrolet Gentra vehicle. The study determined the thermodynamic response characteristics and energy performance of the system under varying ambient temperatures (-10 to +50 °C) and engine thermal loads. The experimental results demonstrated that the mechatronic system can maintain coolant temperature with minimal fluctuation amplitude, ensure smooth transient processes, and significantly reduce electrical energy consumption. Based on the obtained results, scientific and practical …