Other Mechanical Engineering Commons^™

Economic Assesment Of The Impact Of Climate Factors On Wheat Yield In Samarkand Region, Sh.B. Babakholov

Irrigation and Melioration

Agricultural production is highly vulnerable to climate shocks and predicted climate consequences may pose severe challenges to the resilience of Uzbek agricultural system, especially in terms of food security and income stability of rural producers. In this context, present study proposed to assess the impact of climate factors, such particular changes in mean temperature and rainfalls on total output of wheat-cultivating farmers in Samarkand region. By considering irrigation source and heterogeneous geography of the region, farmers engaged in wheat production were analyzed in two: upstream and downstream zones using Fixed effect panel approach. The empirical findings of study revealed that, …

Change In Level Water In Pumping-Plant Intake, R.R. Ergashev, B.T. Xolbutayev

Irrigation and Melioration

A decrease in the water level in the pump chamber of the pumping stations leads to the formation of whirlpools in front of the suction pipes. As a result of air intake, the pump unit operates in cavitation mode and their intensive wear occurs. As the data obtained from the Karshi machine channel show, mainly a decrease in design water levels in the downstream waters is observed at the first pumping station. Depending on the number of simultaneously operating pumping units, the minimum water level in the head pumping station should be from 4.5 m to 5.7 m. The received …

Modeling The Impact Of Changes In The Ground Water Level On The Stability Of Agricultural Landscapes Using Gis, A.M. Arifjanov, L.N. Samiev, F.K. Babajanov, G.M. Xamdamova, Sh.N. Yusupov

Irrigation and Melioration

The article presents modern GIS methods for determining the stability of changes in irrigated areas and the depth of the ground water level.the most correct solutions are given in modeling this process. To distinguish agricultural landscapes, the classification of agricultural acreage in the lower part of the Amu Darya river region was made using 16-day periodic rasters 2017 of 2018 and the NDIS MOD13Q1 sensor of agricultural acreage, type NDVI. The annual change in the level of underground water in relation to the state of rivers and channels is analyzed. A steady change in agricultural acreage on the right Bank …

Determination And Assessment Of The Spatio-Temporal Changing Dynamics In The Groundwater Level And Mineralization In Irrigated Areas Under Climate Change (As An Example Of Syrdarya Province), S. Khasanov, S. Adilov, R. Kulmatov

Irrigation and Melioration

In the irrigated lands of the Aral Sea Basin, salinization processes are taking place as a result of rising groundwater levels and increasing its mineralization due to the unsustainable use of water and land resources. This, in turn, leads to the withdrawing of arable land and a decrease in crop yields. This is especially the case in the irrigated areas of the lower reaches of the Amudarya and Syrdarya rivers, located in Uzbekistan, southern Kazakhstan, and Turkmenistan. This research was aimed to learn and evaluate the long-term changing behavior of groundwater level and mineralization in the irrigated areas of the …

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

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

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

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

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

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

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. …

Modeling Airflows And Voc Source Strengths For An Occupied School, Brett Stinson

University Honors Theses

Volatile organic compounds (VOCs) are a group of air pollutants that can adversely impact human health, engage in chemistry indoors, and meaningfully degrade indoor and outdoor urban air quality. While extensive research with regard to VOC emission rates from indoor sources has been conducted, it was not until recently that this work began to focus on characterizing emissions from humans and human activity in depth. As buildings are constructed to be increasingly airtight, and the materials utilized are chosen to reduce VOC emissions, it follows that human contributions are poised to become increasingly important indoor sources of VOCs. Utilizing data …

The Effect Of Free-Stream Turbulence On Turbulent Boundary Layers And Convective Heat Transfer From Flat Plates, Ivian Carolina Alfaia De Magalhaes

Electronic Thesis and Dissertation Repository

The present work investigates the effect of free-stream turbulence (FST) on turbulent boundary layers and forced convective heat transfer from flat plates. High resolution, 2-D and 3-D, steady Reynolds-Averaged Navier-Stokes (RANS) simulations using Computational Fluid Dynamics (CFD) techniques were performed to analyze the influence of different free-stream conditions, such as turbulence intensity (TI), integral length scale (L_u) and free-stream velocity (U_o) on local and total skin friction and convective heat transfer coefficients (CHTC), as well as on turbulent boundary layer parameters (boundary layer thickness and momentum thickness). The present study shows that …

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 …

Applying Clustering To Optimize Markovian Models In Human-Machine Interactions, Griffon Mcmahon

The Journal of Purdue Undergraduate Research

No abstract provided.

Feasibility Study On Environmental Protection Reform Of Ship Stern Tube System Based On Water Lubrication, Yang Cui

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.

The Study Of Bubble Growth Hydrodynamics In The Supersaturated Liquids, Raj Kumar Nayak Maloth

Electronic Thesis and Dissertation Repository

Bubble formation and dissolution have a wide range of industrial applications, from the production of beverages to foam manufacturing processes. The rate at which the bubble expands, or contracts has a significant effect on these processes. In the current work, the hydrodynamics of an isolated bubble expanding due to mass transfer in a pool of supersaturated gas-liquid solution is investigated. The complete scalar transportation equation (advection-diffusion) is solved numerically and it has been observed that the present model predicted an accurate bubble growth when compared with existing approximated models and experiments. The effect of gas-liquid solution parameters such as inertia, …

Homogenization Of Composite And Cellular Materials Incorporating Microstructure And Surface Energy Effects, Ahmad Gad

Mechanical Engineering Research Theses and Dissertations

In the last few decades, the popularity of composite and cellular materials has rapidly increased through their widespread applications in multiple engineering fields including aerospace, automotive, civil and biomedical. However, to a large extent, the success of their practical applications depends on our ability to predict their mechanical behavior by using high-fidelity mechanics models.

Micromechanical modeling of composite and cellular materials is a challenging task due to the heterogeneous nature of such materials and the interactions among various constituent phases at the microscopic level, which result in non-homogeneous deformation, strain and stress fields. Therefore, it is necessary to develop simple …

Formula Sae Monocoque Chassis Development, Kc Egger, Brian Ford, Kyle Nagao, Neal Sharma, Donovan Zusalim

Mechanical Engineering

Formula SAE is a collegiate competition hosted by SAE International with the primary goal being to design, manufacture, and race an open wheel race car. The Cal Poly Racing Formula SAE team strives for improvement every race season and has remained competitive as a result. The 2019-2020 management team determined that further research and development towards the chassis would yield the greatest performance benefit for future seasons, as the previous chassis platform limited packaging and mounting options for vehicle subsystems which interfaced with the chassis.

A redesign of the Cal Poly Racing Formula SAE team’s carbon fiber reinforced polymer monocoque …

Aqueous Redox Flow Batteries With Boron Doped Diamond As An Electrode., Alex M. Bates

Electronic Theses and Dissertations

As the interest and implementation of renewable energy accelerates, so does that of grid energy storage. It is widely believed that a cost-effective energy storage technology will bring about the proliferation of renewable energy. Redox flow battery (RFB) technology represents a promising solution to cost-effective grid energy storage. Compared to other technologies, RFBs have a long lifetime, high efficiency, are non-flammable, significantly reduce cost, and separately scale power and energy. The separation of power and energy enables increased energy capacity by simply adding electrolyte volume. Of the challenges facing RFB technology, one readily apparent is the cost of the active …