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Joint Assessment Of Characteristics Of Object Parameters And Statistical Characteristics Of Disturbing Influences, Yulduz Mukhtarkhodzhaevna Abdurakhmanova

Technical science and innovation

The paper considers the problem of joint estimation of object parameters and statistical characteristics of random disturbances based on data from independent experiments. It is indicated that the use of the method of moments for the problem under consideration gives estimates that are not effective in the Rao-Kramer sense and the most common asymptotically effective estimation method, in this sense, is the maximum likelihood method(ML). However, in the case of objects with several disturbances that have distribution densities of a general form, the implementation of the ML method is difficult, since to find the values of the distribution density it …

Qualitative Analysis Of The Circuits Of Autonomous Inverters With Shut-Off Valves, Shukhrat Badreddinovich Umarov

Technical science and innovation

The article presents the results of a qualitative analysis of circuits of autonomous current and voltage inverters with cut-off valves; the influence of the charge value of the switching capacitor in parallel and series equivalent circuits on the restoration of the switching properties of the thyristors of the inverter power circuit is studied. It is shown that due to the energy periodically accumulated in the inductive elements of the load, the voltage on the switching capacitor in the cut-off state is greater than in a conventional parallel autonomous current inverter. This circumstance ensures an increase in the switching stability of …

Determination Of Techno-Economic Indicators Of Pumped Storage Power Plants Under The Operational Conditions Of The Tuyamuyun Hydro Complex, Kurbon Salikhdjanovich Dzhuraev, Abdurauf Abduaziz Uulu, Fotima Tulkunovna Shadibekova

Technical science and innovation

The article presents the results of research on the analysis of the state of the electric power system of the Republic of Uzbekistan, taking into account the operating modes of hydraulic and thermal power plants with the study of the sharp-peak nature of the electric load in the winter and summer periods of the year and the problems of covering daily load schedules due to a lack of maneuverable capacities. The use of pumped storage power plants is proposed to cover and smooth daily load schedules across months and seasons. The necessity of utilizing the capacity of pumped storage power …

Method For Calculating Characteristic Frequency Ab (Rechargeable Batteries), Alisher Ganisher Ugli Bozorov

Technical science and innovation

A method for calculating the characteristic frequency is proposed, based on automatic interpolation of the frequency dependence of the reactance and subsequent calculation of the characteristic frequency as one of the roots of the interpolation function. The developed algorithm allows you to calculate the characteristic frequency from only 4 points of the frequency dependence of the reactance. In this case, the error in calculating the resonant frequency parameter does not exceed ~2 Hz.

Obviously, the values of the coefficients of the equation depend on the number of resistance values X and the corresponding frequencies of the test signal. The indicated …

Enhancing Dynamic Impact Mechanical Properties Of Ultra-High-Performance Concrete With Steel Fiber Reinforcement, Oybek Valijonovich Tuyboyov, Sultonmurod Bekpulatovich Normatov

Technical science and innovation

This study investigates the dynamic impact mechanical properties of Ultra-High-Performance Concrete (UHPC) with high-content and directional reinforced steel fiber. The research explores the influence of directional distributed steel fiber on the dynamic impact properties of UHPC specimens prepared with varying fiber contents. Through experimental analysis using the split-Hopkinson pressure bar (SHPB) method, stress-strain curves, stress peaks, dynamic increase factor (DIF), and ductile energy absorption properties of the specimens at different strain rates were obtained. The results demonstrate that oriented steel fiber significantly enhances the dynamic properties of UHPC, with notable improvements in peak strain, peak stress, and energy absorption capacity. …

Development Of An Effective Container Design That Reliably Provides Isolation Of Water Inflow And Elimination Of Well Flooding, Tolib Olimovich Komilov Suffix, Sherali Hallokovich Umedov, Anvarkhoja Akbarkhodjayevich Rakhimov

Technical science and innovation

Currently, the hydrocarbon extraction industry is one of the most high-tech and rapidly developing sectors globally. The primary priority of this industry is to improve the technical and economic indicators of drilling and well operation. A particularly pressing issue is reducing well waterlogging and effectively isolating water flows, which contributes to optimizing hydrocarbon resource development. The introduction of modern equipment into production processes increases the demand for hydrocarbon resources, further complicating the challenges faced by the industry. This article highlights the relevance of applying innovative technologies to address well complications. Specifically, a new technology for isolating water flows and eliminating …

On Resource Testing Of Straight-Bevel Gears In Drive Mechanisms Of Cotton Machines, Shoraxmat Asqarovich Shaabidov, Umid Mamazokir Ugli Mamasobirov, Azizbek G‘Ulom O‘G‘Li Xusanbayev

Technical science and innovation

This article is dedicated to endurance testing of straight-tooth bevel gear reducers used in various machines, including cotton farming machinery. The choice of the test object is due to the fact that many machines require bevel gear transmissions for spatial arrangement of components. These gears enable the transmission of rotational motion between intersecting shaft axes within compact external dimensions. Additionally, bevel gear transmissions are the most common type of gear mechanisms after cylindrical ones.

For several objective reasons, straight-tooth bevel gears have gained wide use. Unlike cylindrical gears, they are more sensitive to manufacturing and assembly errors as well as …

Electrochemical-Method-Induced Strong Metal-Support Interaction In Pt-Cnt@Sno2 For Co-Tolerant Hydrogen Oxidation Reaction, Shen-Zhou Li, Zi-Jie Lin, Qi-An Chen, Zhao Cai, Qing Li

Journal of Electrochemistry

Inducing the classic strong metal-support interaction (SMSI) is an effective approach to enhance the performance of supported metal catalysts by encapsulating the metal nanoparticles (NPs) with supports. Conventional thermal reduction method for inducing SMSI processes is often accompanied by undesirable structural evolution of metal NPs. In this study, a mild electrochemical method has been developed as a new approach to induce SMSI, using the cable structured core@shell CNT@SnO₂ loaded Pt NPs as a proof of concept. The induced SnO_x encapsulation layer on the surface of Pt NPs can protect Pt NPs from the poisoned of CO impurity in …

Dendrite-Free Strategies For Aqueous Zinc-Ion Batteries: Structure, Electrolyte, And Separator, Gang Wu, Wu-Hai Yang, Yang Yang, Hui-Jun Yang

Journal of Electrochemistry

Continued growth in energy demand and increased environmental pollution constitute major challenges that need to be addressed urgently. The development and utilization of renewable, sustainable, and clean energy sources, such as wind and solar, are crucial. However, the instability of these intermittent energy sources makes the need for energy storage systems increasingly urgent. Aqueous zinc-ion batteries (AZIBs) have received widespread attention due to their unique advantages, such as high energy density, cost-effectiveness, environmental friendliness, and safety. However, AZIBs face significant challenges, mainly the formation of zinc dendrites that seriously affect the stability and lifetime of the batteries, leading to battery …

All-Solid-State Sodium-Ion Batteries: A Leading Contender In The Next-Generation Battery Race, Rui-Jie Zhu, Ze-Chen Li, Wei Zhang, Akira Nasu, Hiroaki Kobayashi, Masaki Matsui

Journal of Electrochemistry

All-solid-state lithium-ion batteries (LIBs) using ceramic electrolytes are considered the ideal form of rechargeable batteries due to their high energy density and safety. However, in the pursuit of all-solid-state LIBs, the issue of lithium resource availability is selectively overlooked. Considering that the amount of lithium required for all-solid-state LIBs is not sustainable with current lithium resources, another system that also offers the dual advantages of high energy density and safety— all-solid-state sodium-ion batteries (SIBs) —holds significant sustainable advantages and is likely to be the strong contender in the competition for developing next-generation high-energy-density batteries. This article briefly introduces the research …

Contributions To Journal Of Electrochemistry, The Flagship Journal Of Chinese Chemical Society Electrochemical Committee, Will Be Listed As A New Recommendation Policy For China Youth Awards Of Electrochemist, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Refinement Of An Algorithm To Detect And Predict Freezing Of Gait In Parkinson Disease Using Wearable Sensors, Allison M Haussler, Lauren E Tueth, David S May, Gammon M Earhart, Pietro Mazzoni

2020-Current year OA Pubs

Freezing of gait (FOG) is a debilitating symptom of Parkinson disease (PD). It is episodic and variable in nature, making assessment difficult. Wearable sensors used in conjunction with specialized algorithms, such as our group's pFOG algorithm, provide objective data to better understand this phenomenon. While these methods are effective at detecting FOG retrospectively, more work is needed. The purpose of this paper is to explore how the existing pFOG algorithm can be refined to improve the detection and prediction of FOG. To accomplish this goal, previously collected data were utilized to assess the prediction ability of the current algorithm, the …

Modeling Heat Flux Effects On Spacecraft At Atmospheric Re-Entry, Khalid Ayoola, Carson Running

Mechanical Engineering Student Publications

Spacecraft re-entry involves complex thermal and fluid dynamic interactions that critically impact vehicle design and survival. This research investigates heat flux dynamics during atmospheric transition, utilizing the Fay-Riddell equation to model heat transfer through spacecraft surfaces under varying conditions of altitude, Mach number, and nose radius. Key findings reveal that heat flux decreases exponentially with altitude, increases with velocity, and varies significantly with geometric configuration. The analysis demonstrates heat flux ranges from 3.21 × 10^4 W/m^2 with a 3m nose radius at Mach 10 and 30km altitude to 8.32 × 10^6 W/m^2 with a 0.1m nose radius at ground level, …

Gravitational Water Vortex Generator, Lance Roadifer, Carson Running

Mechanical Engineering Student Publications

No abstract provided.

Assessment Of Coffee Yields Using Unmanned Aerial Vehicle Techniques, Sawitree Chansing

Journal of Letters

The objective of this research is to study factors related to coffee yields and to develop a model for assessing the productivity of Arabica coffee based on data obtained from unmanned aerial vehicle (UAV) in Ban San Charoen, Tha Wang Pha District, Nan Province, during the 2021-2022 harvest seasons. The researchers used variables which are plant height, canopy size, trunk circumference, and visible atmospherically resistant index (VARI). These variables are related to coffee yields using linear regression analysis and evaluated statistical reliability using the coefficient of determination (R2), and the root mean square error (RMSE) were employed. The research findings …

New York Times V. Sullivan: A Civil Rights Story, Samantha Barbas

Texas A&M Law Review

The 1964 Supreme Court decision in New York Times v. Sullivan established the “actual malice” rule in libel law, requiring that in order to win a libel suit, a public official must show that a defamatory statement was false and that the speaker made the statement knowing that it was false or “with reckless disregard of whether it was false or not.”

Sullivan involved a libel suit brought by segregationist Alabama officials against the New York Times (“Times”) and leaders of the civil rights movement. Sullivan arose from sectional battles over civil rights and integration in the 1960s. An all-white …

Effectives Strategies Leaders Use To Engage Nurses In Safe Work Practices, Madeline Ortiz Gonzalez

Walden Dissertations and Doctoral Studies

Work-related injuries remain a significant challenge in the healthcare sector, leading to reduced productivity and financial losses despite improvements in workplace safety. Healthcare leaders are concerned that unsafe work practices negatively affect organizational performance and service quality. Grounded in Burn’s transformational leadership framework, the purpose of this qualitative pragmatic inquiry study was to explore effective strategies used by six nurse leaders in Southern United States use to encourage nurses to adopt safe work practices and foster a culture of safety. Through thematic analysis, three core themes were identified: implementing comprehensive training programs, establishing effective communication channels, and fostering a safety-first …

A Comparative Analysis Of The County-Level Covid-19 Lockdown’S Impact On Child Sexual Abuse Rates, Aunastasia Fantasia Marie Zsidiewicz

Walden Dissertations and Doctoral Studies

National reported rates of childhood sexual abuse (CSA) during the COVID-19 pandemic lockdown were significantly lower than expected. This quantitative study explored rates of CSA before and after the lockdown for 22 Michigan counties by considering socioeconomic status (SES) demographics to isolate the lockdown’s specific impact on reported CSA rates. The SES of the counties was measured using the Kuppuswamy scale, a numerical compilation of the mean occupation, education, and income of households within a given county. The Social Determinants of Health framework provided a blueprint for understanding the impact of exploring the different socioeconomic variables. This framework also helped …

Enriched Microbial Consortia From Natural Environments Reveal Core Groups Of Microbial Taxa Able To Degrade Terephthalate And Terphthalamide, Laura G. Schaerer, Sulihat Aloba, Emily Wood, Allison Olson, Isabel B. A. Valencia, Rebecca Ong, Stephen Techtmann

Michigan Tech Publications

Millions of tons of polyethylene terephthalate (PET) are produced each year, however only ~30% of PET is currently recycled in the United States. Improvement of PET recycling and upcycling practices is an area of ongoing research. One method for PET upcycling is chemical depolymerization (through hydrolysis or aminolysis) into aromatic monomers and subsequent biodegradation. Hydrolysis depolymerizes PET into terephthalate, while aminolysis yields terephthalamide. Aminolysis, which is catalyzed with strong bases, yields products with high osmolality, which is inhibitory to optimal microbial growth. Additionally, terephthalamide, may be antimicrobial and its biodegradability is presently unknown. In this study, microbial communities were enriched …

Factors Affecting Waiting Times To Enter Opioid Use Disorder Treatment In The United States With A Particular Focus On Potential Biological Sex Disparity, Stanley Nkemjika, Kenneth Oforeh, Connie Olwit, Olaniyi Olayinka, Terence Tumenta

Department of Psychiatry and Human Behavior Faculty Papers

AIM: Opioid use disorder (OUD) is the problematic use of licit or illicit opioids. Thus far, the literature on biological sex differences in accessing treatment is scarce. Hence, we hypothesize that biological sex has a moderating effect on OUD treatment accessibility. We aim to explore biological sex differences in treatment disparities and its role in wait time to enter OUD treatment.

METHOD: Using the 2018 Treatment Episode Data Set Discharge, the national sample representative of OUD patients in the substance use disorder treatment facilities within the 50 states of the United States was 382,547. Univariate and multivariable logistic analysis of …

Effects Of Pollution On The Flow Of The Gowanus Canal, Eleanore Dzija, Carson Running

Mechanical Engineering Student Publications

This paper explores how pollution affects the flow of the Gowanus Canal. Four scenarios are modeled to represent different phases of pollution remediation: no remediation, dredging and capping of the canal bottom, combined sewer overflow capture, and dredging and capping with combined sewer overflow capture. Dredging and capping of the canal bottom resulted in the greatest increase in velocity. Dredging and capping with combined sewer overflow capture resulted in the greatest decrease in pressure. This indicates that dredging and capping of the canal bottom may be the most efficient pollution remediation strategy and should be the focus of the cleanup …

The Effect Of Temperature On Power Output From A Hydroelectric Penstock, Taylor Hartell, Carson Running

Mechanical Engineering Student Publications

Hydroelectric power is a form of renewable energy that uses the power from water to generate electricity. One of the ways this is done is by diverting water from a river with a penstock leading to a turbine. Hydroelectric systems rely on water as the source of power, and the viscosity of water varies with temperature. When temperatures are low, viscosity is high, and when temperatures are high, viscosity is low. Other works have studied the optimal dimensions of penstocks for power generation and the effect of hydroelectric power on river temperatures. In this research, the effect of temperature on …

Comparative Study Of Aerodynamic Characteristics Of Standard And Dimpled Naca 0012 Airfoil, Fahim Shahriyar, Carson Running

Mechanical Engineering Student Publications

This study analyzes the aerodynamic performance of a NACA 0012 airfoil with dimples on its upper surface, comparing it to the standard configuration. Using the Navier-Stokes equations, Blasius solutions, the k-ε turbulence model, and ANSYS Fluent, steady-state incompressible flow was simulated at 25 m/s across angles of attack from -20° to +20°. Results show the standard airfoil performs well at the low Reynolds number and lower angle of attack. The inward dimple airfoil reduces drag at negative angles, while the outward dimple airfoil enhances lift at higher positive angles. Shear stress analysis reveals laminar flow on flat plates and turbulent …

Environmental Assessment Of The Level Of Concentration Of Nickel And Lead In The Soil Of River Basins In The Samawa District, Turki Attia Tayeh, Anwar Sabah Muhammad

Uruk Journal of Human Sciences

The current study concluded by evaluating the level of concentration of nickel (Ni) and lead (Pb) in the soil of the river basins of Samawah District, north of Muthanna Governorate. Soil samples were taken from (12 sites) to two depths (0-30 cm) and (31-60 cm), in addition to the site (CP). (In the soil of the banks of the Euphrates River as a reference area for comparison and analysis purposes, the soil texture, its apparent and real density, and the percentage of porosity were measured. The research aims to determine the reasons for the high values ​​of the elements nickel …

Iraqi Efl College Learners’ Performanceof Adjective Placement Order, Hisham Adnan Almumar, Muhtaram Abdulwahid Al-Owaidi

Uruk Journal of Human Sciences

This paper deals with the preferable order of adjectives as one of the open classes in English grammar where various adjectives describe a following noun or pronoun. It also tends to identify the students' perception of the placement of patterns of adjectives. The problem of this study lies precisely in the sense that this subject may cause difficulty for Iraqi students in ordering multiple successful adjectives in a spoken or written form of the language. For this reason, it accounts for the causes of the dominant errors made by the undergraduates and their sources. To evaluate the student's strengths and …

Effectives Strategies Leaders Use To Engage Nurses In Safe Work Practices, Madeline Ortiz Gonzalez

Walden Dissertations and Doctoral Studies

Work-related injuries remain a significant challenge in the healthcare sector, leading to reduced productivity and financial losses despite improvements in workplace safety. Healthcare leaders are concerned that unsafe work practices negatively affect organizational performance and service quality. Grounded in Burn’s transformational leadership framework, the purpose of this qualitative pragmatic inquiry study was to explore effective strategies used by six nurse leaders in Southern United States use to encourage nurses to adopt safe work practices and foster a culture of safety. Through thematic analysis, three core themes were identified: implementing comprehensive training programs, establishing effective communication channels, and fostering a safety-first …

Shark Skin Riblet Microstructures: An Oceanic Solution To Reduce Shear Wall Stress And Skin Friction, Ashyln Veitz, Carson Running

Mechanical Engineering Student Publications

Minimizing energy consumption and its associated costs is a key priority in engineering. Potential solutions are found in nature, particularly the skin of the shortfin mako shark. The riblet microstructures have been shown to reduce drag, offering a promising method for energy reduction in various industries. This study investigates the effectiveness of riblet microstructures in reducing wall shear stress and skin friction in laminar flow. The flow over a flat plate is compared with flow over a riblet-structured surface, considering the impact of the temperature of the fluid. Results show that as temperature increases, shear wall stress and skin friction …

An Analysis Of Flow Properties Of Shock Tube Boundary Layer, Cheyenne Harrison, Carson Running

Mechanical Engineering Student Publications

Ice crystal behaviors in the upper atmosphere are very unknown and under-researched, leaving them a mystery as to how they might interact with objects traveling through this region. Currently the University of North Dakota Aerosol Engineering Laboratory is creating an experiment to drop an ice crystal through a vale on a shock tube. This project aimed to solve for properties of the air flow traveling through the shock tube to see how it might affect the falling ice crystal. These properties included Reynolds number, boundary layer thickness, wall shear stress, and velocity contours of the boundary layer. Through Excel and …

The Effects Wind Has On Ocean Current Speeds For Marine Renewable Energy Applications, Parkerjay Hoaglund, Carson Running

Mechanical Engineering Student Publications

This paper explores the influence of wind on ocean current speeds at varying depths and its implications for marine renewable energy systems, particularly underwater turbines. By analyzing the fluid mechanics of ocean currents and applying the Navier-Stokes equations under simplified assumptions, velocity and pressure profiles were developed to model the interaction between wind and water. The research highlights the dependence of ocean current velocity on wind speed and depth, demonstrating that maximum current speeds and power generation potential occur near the ocean surface. Using MATLAB simulations, power generation by an underwater turbine was analyzed under varying wind speeds and depths, …

Airflow Over Nasa’S X-59, Quiet Supersonic Technology (Quesst), Laina Behrenbrinker, Carson Running

Mechanical Engineering Student Publications

The X-59 QueSST is an experimental aircraft that will reach supersonic speeds without producing a loud sonic boom. Those on the ground will hear something like distant thunder as the X-59 passes overhead, around 75 dB. This paper studies the pressure distribution over the nose of the X-59 and the Sound Pressure Level (SPL) on the surface of the X-59 nose (1/3 of the total vehicle length) to better understand how sound propagates through the atmosphere. The resulting SPL over the aircraft nose is 180 – 190 dB, and further the SPL on the ground is calculated to be 43-53 …