Open Access. Powered by Scholars. Published by Universities.®

Engineering Science and Materials Commons™

Open Access. Powered by Scholars. Published by Universities.®

5,752 Full-Text Articles 13,421 Authors 3,157,969 Downloads 140 Institutions

All Articles in Engineering Science and Materials

Faceted Search

5,752 full-text articles. Page 100 of 209.

Increasing The Efficiency Of Water Distribution Management When Operating Pumping Stations Of The Irrigation System, O.Y. Glovatsky, R.R. Ergashev, B. Hamdamov, N.M. Ismailov, B.T. Kholbutaev 2020 Research Institute of Irrigation and Water Problems

Increasing The Efficiency Of Water Distribution Management When Operating Pumping Stations Of The Irrigation System, O.Y. Glovatsky, R.R. Ergashev, B. Hamdamov, N.M. Ismailov, B.T. Kholbutaev

Irrigation and Melioration

The article is to control the parameters of the unsteady movement of water in the canals and the pumping station, which ensure the maintenance of the specified operating modes of the pumping stations under non-stationary conditions. To achieve this goal, it is necessary to solve the problems of coordinating the operating modes of the units of the head pumping station (PS) with the operating modes of the partitioning structures in the conditions of emptying and filling the ponds of the main canal with water. The article discusses the implementation of the method of water distribution control on the mathematical model …


Analysis Of Theoretical And Natural Field Studies Of Reservoir Silling, A.M. Arifjanov, F. Gapparov, T.U. Apakhujayeva, S.N. Xoshimov 2020 Tashkent Institute of Irrigation and Agricultural Mechanization Engineers

Analysis Of Theoretical And Natural Field Studies Of Reservoir Silling, A.M. Arifjanov, F. Gapparov, T.U. Apakhujayeva, S.N. Xoshimov

Irrigation and Melioration

The article developed a mathematical model of the processes of siltation of reservoirs, taking into account the energy state of the flow, and proposed a calculation method. In the process of siltation of the reservoir, the dependence of the volume on the change in the water level in the reservoir was estimated. On the basis of studies carried out in full-scale field conditions, the recommended calculation method is comparatively evaluated and analyzed. Field studies were carried out in the Chimkurgan, Tashkent and Yuzhno-Surkhan reservoirs. A relationship is obtained that expresses the dependence of the relative volume of siltation of the …


Planed Dimension Of Flow Deformed By A Single Dam That Is Impermeable To Water From The Body, M.R. Bakiev, K.T. Yakubov, I.J. Asamatdinov 2020 Tashkent Institute of Irrigation and Agricultural Mechanization Engineers

Planed Dimension Of Flow Deformed By A Single Dam That Is Impermeable To Water From The Body, M.R. Bakiev, K.T. Yakubov, I.J. Asamatdinov

Irrigation and Melioration

Coastal erosion is a type of water erosion that causes significant damage to the national economy each year: leaching of overland coastal crops, failure of protective dams, destruction of irrigation canals, dilapidated buildings and structures, among others. To combat leaching, cross-dams are used which are waterproof and water-permeable. The aim of this work was to develop a method for calculating the planned dimension of compressed flow with a transverse dam, which included comparing the lengths of the upper and lower tilt zones, the boundaries of individual zones and the results of research in the laboratory and in nature. According to …


Research Of Energy Indicators Of Electric Drives With Frequency Converters (Frequency Converters) On The Operating Equipment Of Cotton Cleaning Plants, A.J. Isakov, B.K. Tukhtamishev, J.N. Tolipov 2020 Tashkent Institute of Irrigation and Agricultural Mechanization Engineers

Research Of Energy Indicators Of Electric Drives With Frequency Converters (Frequency Converters) On The Operating Equipment Of Cotton Cleaning Plants, A.J. Isakov, B.K. Tukhtamishev, J.N. Tolipov

Irrigation and Melioration

The article deals with the theoretical and practical substantiation of the replacement of an unregulated electric drive of the main technological equipment of cotton refineries with a frequency-controlled electric drive. The influence of a change in the load on the motor shaft on the main parameters of the steady state is considered. In an asynchronous motor, with an increase in the load, slip increases to such a value at which the torque of the motor balances the increased moment of resistance. Considering that when the stator slip resistance is less than the critical one is a small fraction of the …


Stabilization Of Discharge Processes Involved In Electrical Fields Of Electrostatic Precipitators, Sh.M. Muzafarov, B.N. Erkinov, A.I. Pardaev, V.E. Baliskiy, B.К. Tаgaev 2020 Tashkent Institute of Irrigation and Agricultural Mechanization Engineers

Stabilization Of Discharge Processes Involved In Electrical Fields Of Electrostatic Precipitators, Sh.M. Muzafarov, B.N. Erkinov, A.I. Pardaev, V.E. Baliskiy, B.К. Tаgaev

Irrigation and Melioration

The article provides information on achievements in the field of electrical gas cleaning. A critical analysis of the principle of operation of the electrostatic precipitators developed and currently in operation is carried out. The possibility of increasing the efficiency of electrical gas cleaning using unipolar voltage pulses is analyzed. A theoretical analysis of the processes in the discharge gap was carried out using the existing theory of electric discharges in gases. Based on the analysis of the data, the discharge mechanism is established in a sharply inhomogeneous electric field at a pulsed voltage. It is established that when using voltage …


Determination Of The Rational Values Of The Parameters Of The Disc Rollers Of The Combined Unit, A.K. Igamberdiev, D.K. Muqimova 2020 Tashkent Institute of Irrigation and Agricultural Mechanization Engineers

Determination Of The Rational Values Of The Parameters Of The Disc Rollers Of The Combined Unit, A.K. Igamberdiev, D.K. Muqimova

Irrigation and Melioration

In our country, repeated crops are sown in newly plowed lands. In such conditions, the use of combined units that perform several technological operations simultaneously in one pass is considered effective. However, due to the inadequacy and validity of the parameters of the working bodies for the quality of pre-sowing tillage in newly plowed lands, there is an increase in the number of passes, fuel consumption, loss of soil moisture and other costs and, as a result, the possibility of timely sowing and friendly germination of repeated crops is reduced . The rational parameters of the new design of disk …


Autonomous Photovoltaic System For Year-Round Guarantee Supply Of Electricity To Rural Facilities, M.N. Tursunov, Х. Sabirov, U.R. Kholov, Т.Z. Аkhtamov 2020 Physical-technical institute of SPA “Physics-Sun” of the Academy of Science of Uzbekistan

Autonomous Photovoltaic System For Year-Round Guarantee Supply Of Electricity To Rural Facilities, M.N. Tursunov, Х. Sabirov, U.R. Kholov, Т.Z. Аkhtamov

Irrigation and Melioration

The article discusses the physical and technical features of the experimental results of studying the parameters of an autonomous photovoltaic station (AFES) with a power of 2600 W designed and manufactured on the basis of 16 photovoltaic batteries made of polycrystalline silicon with an efficiency of 15.6 %. It is shown that an autonomous photovoltaic efficiently and reliably provides electric energy a lighting system for car parking in the winter season (January and February) and it is planned to lift water from a well with a depth of 70-80 m for irrigation and maintenance of the Heliopoligon from April 2020. …


Enhanced Optical Propulsion And Material Analysis For Multiple Rayleigh Particles, Christopher Alan Jones 2020 Arkansas State University

Enhanced Optical Propulsion And Material Analysis For Multiple Rayleigh Particles, Christopher Alan Jones

Student Theses and Dissertations

Studies have shown that materials exhibiting specific attributes can be propelled forward by photons of varying wavelengths within the visible light spectrum. This is enhanced by a momentum reversal due to the wave scattering of ejected electrons. Research has indicated that these effects are due to a particle's size and shape. Furthermore, these effects can lead to a tunability within cylinders/rods. The present research aims to provide an approximate macroscopic solution using Rayleigh theory to assess single and multiple particle forces for both ideal and causal systems. The forces are acquired through the integration of the Minkowski stress tensor just …


The Concept Of The Mathematical Description Of The Multi-Coordinate Mechatronic Module Of The Robot, Temurbek Omonboyevich Rakhimov 2020 Doctoral student of Tashkent State Technical University named after Islam Karimov

The Concept Of The Mathematical Description Of The Multi-Coordinate Mechatronic Module Of The Robot, Temurbek Omonboyevich Rakhimov

Acta of Turin Polytechnic University in Tashkent

The article deals with the concept of mathematical de- scription of multi-coordinate mahatronic modules of robots. The main results of the work are a generalized structure of a multi- coordinate mechatronic module of motion, a kinematic diagram of an electromagnetic multi-coordinate mechatronic module with three independent coordinate linear and angular movements is proposed, consisting of four electromagnets, controlled couplings designed to transmit the reciprocating motion of the moving parts of electro- magnets to the output rods and a cable, which are associated with the links of work and bringing them into linear and angular mo- tion. A simulation model of …


Preparation Characterization And Tribological Behavior Of Lube Oil With Nanoparticles Additives, Waleed Alghani 2020 Universiti Malaya

Preparation Characterization And Tribological Behavior Of Lube Oil With Nanoparticles Additives, Waleed Alghani

Student Works (2020-2029)

There are many companies worldwide that would like to improve and upgrade the lube oil and enhance its performance. There is a big concern for the enhancement of lube oil by using nanotechnology and more precisely with using nanomaterial additives. Much work has made to explore and develop new sorts of lubricating oil nano-additives to diminish wear and friction in tribological configurations and to enhance surface morphology. It has noted that the use of dual nano-additives should examine the lubricating capacity and durability of lubricant. (TiO2 Anatase + Graphene) and (ZnO + Graphene) nanoparticles have selected to formulate nano-additives that …


An Affordable And Portable Palpable System For Sensing Breast Tissue Abnormalities, Cody J. Clarke 2020 Liberty University

An Affordable And Portable Palpable System For Sensing Breast Tissue Abnormalities, Cody J. Clarke

Montview Journal of Research & Scholarship

Due to the high cost of equipment and lack of trained personnel, manual palpation is a preferred alternative breast examination technique over mammography. The process involves a thorough search pattern using trained fingers and applying adequate pressure, with the objective of identifying solid masses from the surrounding breast tissue. However, palpation requires skills that must be obtained through adequate training in order to ensure proper diagnosis. Consequently, palpation performance and reporting techniques have been inconsistent. Automating the palpation technique would optimize the performance of self-breast examination, optimize clinical breast examinations (CBE), and enable the visualization of breast abnormalities as well …


Me-Em 2019-20 Annual Report, Department of Mechanical Engineering-Engineering Mechanics, Michigan Technological University 2020 Michigan Technological University

Me-Em 2019-20 Annual Report, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering Annual Reports

Table of Contents

  • Element 1
  • Element 2
  • Element 3
  • Element 4
  • Enrollment & Degrees
  • Graduates
  • Department
  • Alumni
  • Donors


Fatigue Of A Sic/Sic Ceramic Composite With An Ytterbium‐Disilicate Environmental Barrier Coating At Elevated Temperature, Marina B. Ruggles-Wrenn, Thaddeus M. Williams 2020 Air Force Institute of Technology

Fatigue Of A Sic/Sic Ceramic Composite With An Ytterbium‐Disilicate Environmental Barrier Coating At Elevated Temperature, Marina B. Ruggles-Wrenn, Thaddeus M. Williams

Faculty Publications

Excerpt: Tension-tension fatigue performance of a SiC/SiC composite with an ytterbium-disilicate environmental barrier coating (EBC) was investigated at 1200°C in air and steam. The composite is reinforced with Hi-Nicalon™ SiC fibers and has a melt-infiltrated matrix processed by chemical vapor infiltration of SiC with subsequent infiltration with SiC particulate slurry and molten silicon. Abtract © American Ceramic Society


Me-Em Enewsbrief, September 2020, Department of Mechanical Engineering-Engineering Mechanics, Michigan Technological University 2020 Michigan Technological University

Me-Em Enewsbrief, September 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.


Effect Of Motor-Assisted Elliptical Training Speed And Body Weight Support On Center Of Pressure Movement Variability, Farahnaz Fallahtafti, Chase M. Pfeifer, Thad W. Buster, Judith M. Burnfield 2020 Madonna Rehabilitation Hospitals and University of Nebraska at Omaha

Effect Of Motor-Assisted Elliptical Training Speed And Body Weight Support On Center Of Pressure Movement Variability, Farahnaz Fallahtafti, Chase M. Pfeifer, Thad W. Buster, Judith M. Burnfield

Department of Mechanical and Materials Engineering: Faculty Publications

Background: A motor-assisted elliptical trainer is being used clinically to help individuals with physical disabilities regain and/or retain walking ability and cardiorespiratory fitness. Unknown is how the device’s training parameters can be used to optimize movement variability and regularity. This study examined the effect of motor-assisted elliptical training speed as well as body weight support (BWS) on center of pressure (CoP) movement variability and regularity during training. Methods: CoP was recorded using in-shoe pressure insoles as participants motor-assisted elliptical trained at three speeds (20, 40, and 60 cycles per minute) each performed at four BWS levels (0%, 20%, 40%, and …


Exploration Of Novel Ferroelectric Systems: Determination Of The Underlying Mechanisms, Sizhan Liu 2020 New Jersey Institute of Technology

Exploration Of Novel Ferroelectric Systems: Determination Of The Underlying Mechanisms, Sizhan Liu

Dissertations

Modern environmental and sustainability issues, as well as the growing demand for applications in sensing and data storage, require the discovery and development of new functional materials. Ferroelectrics and multiferroics are materials that have played a central role in this arena. Because the central function of ferroelectrics is governed by spontaneous polarization response, understanding both the electronic and atomic response to external stimuli is important. In this work, a broad set of model systems were explored to determine the fundamental mechanisms involved in the formation of the ferroelectric phase.

Understanding atomic-level changes in structure is important for improving the properties …


Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-neng XU, Jin-li QIAO 2020 1. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China;2. University of Louisiana at Lafayette, Lafayette, LA 70504, USA;

Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao

Journal of Electrochemistry

Zinc-air battery has attracted great attention from researchers due to its high energy density and power density, which is expected to be widely used in energy conversion and storage. Air electrode as the core area of oxygen catalytic reaction is the focus of the entire zinc-air battery research. Recently, many research achievements have been made in non-noble metal bifunctional catalysts/electrodes with high activity, low cost and abundant species. In this review, we mainly focus on the reaction mechanism and the recent progress in non-noble metal oxide catalyst, carbon-based catalyst, and carbon-based transition metal compound composite and self-supporting electrode. In addition, …


Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia FAN, Na HAN, Yan-guang LI 2020 Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, Jiangsu, China;

Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia Fan, Na Han, Yan-Guang Li

Journal of Electrochemistry

Electrochemical carbon dioxide reduction (CO2RR) is an appealing approach to convert atmospheric CO2 to value-added fuels and industrial chemicals, and may play an important role during the transition to a carbon-neutral economy. In order to make this technology commercially viable, it is essential to pursue CO2RR in flow reactors instead of conventional H-type reactors, and to combine electrocatalyst development with system engineering. In this review, we overview the cell configurations and performance advantages of the two types of flow reactors, analyze their shortcomings, and discuss the effects of their different components including gas diffusion electrode …


Electrochemical Energy Storage And Conversion Based On Organic Electrodes, Jian-hang HUANG, Xiao-li DONG, Zhao-wei GUO, Yuan-yuan MA, Yan-rong WANG, Yong-gang WANG 2020 1. Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Institute of New Energy, Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai 200433, China;2. School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang 330063, Jiangxi, China;

Electrochemical Energy Storage And Conversion Based On Organic Electrodes, Jian-Hang Huang, Xiao-Li Dong, Zhao-Wei Guo, Yuan-Yuan Ma, Yan-Rong Wang, Yong-Gang Wang

Journal of Electrochemistry

Aqueous batteries have been considered to be a competitive candidate for large-scale energy storage. However, most of aqueous batteries adopt inorganic electrode materials with metallic elements, which are based on the reversible insertion of metal ions, making their application being highly hindered by limited cycle life, environmental issue, high cost and low reserves. On the other hand, organic electrode materials offer the advantages of abundant reserves, tunable structures, renewability and environmental benignity. Furthermore, the wide internal space enables these organics to flexibly store various charge carriers. Organics have been investigated as the alternative to inorganic electrode materials. Herein, we review …


Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-ning ZHANG, Dong-fang NIU, Shuo-zhen HU, Xin-sheng ZHANG 2020 State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;

Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

The electrochemical conversion of CO2 to chemical raw material for further utilization shows promising future to alleviate global warming and realize carbon cycle in nature, which is of great significance to the green chemistry and sustainable development. This review briefly introduces the advantages of CO2 electrochemical reduction (CO2ER) and its basic reaction principles, and summarizes the recent progress in a series of activity enhancement strategies based on nanosized metal catalysts. The influences of alloy effect, interface engineering, synergistic effect, surface defect engineering and support effect on the catalytic performance of nanosized metals for CO2ER …


Digital Commons powered by bepress