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Irrigation Value The Mechanical Composition River Springs, A.M. Arifjanov, L.N. Samiev, F.K. Babajanov Jun 2020

Irrigation Value The Mechanical Composition River Springs, A.M. Arifjanov, L.N. Samiev, F.K. Babajanov

Irrigation and Melioration

The article studies the influence of the fractional composition of river sediments on the soil structure of irrigated lands and on the process of soil formation. According to surveys in the Mirishkor canal, sediments formed in the river are distinguished by the distribution type in the main canal. The fractional composition of sediments mainly consists of particles of fine sand (0.1-0.05 mm) and coarse dust (0.05-0.001 mm).According to the results of surveys, by studying the mechanical composition of sediment in the channel, it will be possible to observe changes in the amount of composition, such as N-NH4, P2O5, K2O chemicals. …


Modeling The Movement Of A Heap In A Dielectric Sorting Device For Alfalfa Seeds, A. Lee, Z. Sharipov, M.N. Sattarov Jun 2020

Modeling The Movement Of A Heap In A Dielectric Sorting Device For Alfalfa Seeds, A. Lee, Z. Sharipov, M.N. Sattarov

Irrigation and Melioration

This article presents a theoretical study of modeling the movement of a mixture in a dielectric sorting plant for alfalfa seeds. Theoretical studies were carried out using the general laws of mechanics and mathematical modeling of alfalfa seeds, taking into account their physical and mechanical properties. The results of a theoretical study on modeling the detachment conditions of alfalfa seed heap particles and particle dynamics along the casing and pitched boards of a dielectric sorting device are presented. The differential equation with the initial conditions was solved by numerical methods of "Runge-Kutta-Felberg" with automatic step selection. The components of a …


Dynamic Response Of Highway Bridge Superstructures Subjected To Wave Action: Experimental Analysis And Numerical Modeling, Alaa Waleed Hameed Jun 2020

Dynamic Response Of Highway Bridge Superstructures Subjected To Wave Action: Experimental Analysis And Numerical Modeling, Alaa Waleed Hameed

Dissertations and Theses

Bridges are critical lifeline components of the infrastructure network, enabling economies to function under normal conditions and disaster response and recovery missions to take place after extreme events. Therefore, ensuring satisfactory performance increases community resilience and minimizes both human and economic losses. Coastal bridges, which are the focus of this PhD dissertation, are vulnerable to coastal storms. High failure rates of these bridges during two major hurricane events in the mid-2000s have spurred research activities to better understand the wave-induced forces of coastal bridges.

This PhD research represents a continuation effort to build, implement, and introduce new fundamental concepts and …


Design Aspects, Energy Consumption Evaluation, And Offset For Drinking Water Treatment Operation, Saria Bukhary, Jacimaria Batista, Sajjad Ahmad Jun 2020

Design Aspects, Energy Consumption Evaluation, And Offset For Drinking Water Treatment Operation, Saria Bukhary, Jacimaria Batista, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Drinking water treatment, wastewater treatment, and water distribution are energy-intensive processes. The goal of this study was to design the unit processes of an existing drinking water treatment plant (DWTP), evaluate the associated energy consumption, and then offset it using solar photovoltaics (PVs) to reduce carbon emissions. The selected DWTP, situated in the southwestern United States, utilizes coagulation, flocculation, sedimentation, filtration, and chlorination to treat 3.94 m3 of local river water per second. Based on the energy consumption determined for each unit process (validated using the plant’s data) and the plant’s available landholding, the DWTP was sized for solar PV …


Automatic Delamination Segmentation For Bridge Deck Based On Encoder-Decoder Deep Learning Through Uav-Based Thermography, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen Jun 2020

Automatic Delamination Segmentation For Bridge Deck Based On Encoder-Decoder Deep Learning Through Uav-Based Thermography, Chongsheng Cheng, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Concrete deck delamination often demonstrates strong variations in size, shape, and temperature distribution under the influences of outdoor weather conditions. The strong variations create challenges for pure analytical solutions in infrared image segmentation of delaminated areas. The recently developed supervised deep learning approach demonstrated the potentials in achieving automatic segmentation of RGB images. However, its effectiveness in segmenting thermal images remains under-explored. The main challenge lies in the development of specific models and the generation of a large range of labeled infrared images for training. To address this challenge, a customized deep learning model based on encoder-decoder architecture is proposed …


Evaluating Cracking Performance Of Polymer Enhanced And Fiber Reinforced Microsurface Mixtures Using Asphalt Laboratory Testing, George Joseph Shackil Jun 2020

Evaluating Cracking Performance Of Polymer Enhanced And Fiber Reinforced Microsurface Mixtures Using Asphalt Laboratory Testing, George Joseph Shackil

Theses and Dissertations

This study presents a method to improve and evaluate the cracking resistance of microsurfacing mixtures using common asphalt laboratory testing. A preliminary optimal timing study and a study to evaluate improvements to cracking performance were conducted. The control mixture was based on NJDOT standard mix design specifications. Three mixtures were tested in this study: a fiber reinforced mixture using one-quarter inch glass fibers, an emulsion with increased SBR (polymer) contents, and a mixture using the one-quarter inch glass fibers combined with the increased polymer contents. Three laboratory tests were used to evaluate three different cracking resistance parameters: crack initiation (Semi-Circular …


Climate Change Impacts The Subsurface Transport Of Atrazine And Estrone Originating From Agricultural Production Activities, Renys Enrique Barrios, Simin Akbariyeh, Chuyang Liu, Khalid Muzamil Gani, Margarita T. Kovalchuk, Xu Li, Yusong Li, Daniel D. Snow, Zhenghong Tang, John Gates, Shannon L. Bartelt-Hunt Jun 2020

Climate Change Impacts The Subsurface Transport Of Atrazine And Estrone Originating From Agricultural Production Activities, Renys Enrique Barrios, Simin Akbariyeh, Chuyang Liu, Khalid Muzamil Gani, Margarita T. Kovalchuk, Xu Li, Yusong Li, Daniel D. Snow, Zhenghong Tang, John Gates, Shannon L. Bartelt-Hunt

Nebraska Water Center: Faculty Publications

Climate change will impact soil properties such as soil moisture, organic carbon and temperature and changes in these properties will influence the sorption, biodegradation and leaching of trace organic contaminants to groundwater. In this study, we conducted a modeling case study to evaluate atrazine and estrone transport in the subsurface under current and future climate conditions at a field site in central Nebraska. According to the modeling results, in the future, enhanced evapotranspiration and increased average air temperature may cause drier soil conditions, which consequently reduces the biodegradation of atrazine and estrone in the water phase. On the other hand, …


Mobile Manipulating Drones, Paul Oh Jun 2020

Mobile Manipulating Drones, Paul Oh

INSPIRE Archived Webinars

In the past few years, robotic limbs have been attached to rotorcraft drones to perform aerial manipulation. Unlike simple object pick-and-place, such mobile-manipulating drones are dexterous to perform tasks like valve-turning, hatch-opening, and tool-handling. This is a paradigm shift where such drones actively interact with their environment rather than just passively surveil. Aerial manipulation is challenging because such interaction yields reaction forces and torques that destabilize the drone. This talk will provide an overview of aerial manipulation and showcase examples that could serve in infrastructure inspection, maintenance, and repair.


Constitutive Model Of Lateral Unloading Creep Of Soft Soil Under Excess Pore Water Pressure, Wei Huang, Kejun Wen, Xiaojia Deng, Junjie Li, Zhijian Jiang, Yang Li, Lin Li, Farshad Amini Jun 2020

Constitutive Model Of Lateral Unloading Creep Of Soft Soil Under Excess Pore Water Pressure, Wei Huang, Kejun Wen, Xiaojia Deng, Junjie Li, Zhijian Jiang, Yang Li, Lin Li, Farshad Amini

Civil and Architectural Engineering Faculty Research

Presented in this paper is a study on the lateral unloading creep tests under different excess pore water pressures. The marine sedimentary soft soil in Shenzhen, China, was selected in this study. The results show that the excess pore water pressure plays a significant role in enhancing the unloading creep of soft soil. Higher excess pore water pressure brings more obvious creep deformation of soft soil and lower ultimate failure load. Meanwhile, the viscoelastic and the viscoplastic modulus of soft soil were found to exponentially decline with creep time. A modified merchant model and a combined model of the modified …


Nonlinear Breaking-Wave Characteristics In Lagrangian Coordinates, Wen-Jer Tseng, Chia-Yan Cheng Jun 2020

Nonlinear Breaking-Wave Characteristics In Lagrangian Coordinates, Wen-Jer Tseng, Chia-Yan Cheng

Journal of Marine Science and Technology–Taiwan

This paper presents a theoretical investigation of nonlinear surface-wave propagation over a sloping bottom. For a problem with nonlinear surface-wave propagation over a sloping bottom, a perturbation method is first used to find the analytical solution in order to derive the third order terms for the bottom slope  and the wave steepness  in the Eulerian system. Then, by transforming the flow field solution from the Eulerian system into the Lagrangian system, a more accurate wave profile is identified. By using the kinematic stability parameter, new theoretical breaking-wave characteristics are derived. The theoretical solutions are then compared with those …


Assessment Of Dynamic Response Of Offshore Jacket Platforms Subjects To Random Waves, Xiaoshuang Han, Weiliang Qiao, Bo Zhou Jun 2020

Assessment Of Dynamic Response Of Offshore Jacket Platforms Subjects To Random Waves, Xiaoshuang Han, Weiliang Qiao, Bo Zhou

Journal of Marine Science and Technology–Taiwan

This paper presents a simplified approach to analyze the dynamic response of offshore jacket platform based on Timoshenko beam theory. In the study, the jacket platform is simulated as a non-uniform cantilever beam structure subjects to random waves. The assessment of dynamic performance is based on the power spectral densities, variances and spectral moments due to wave spectrum. A combination of Pseudo-excitation and Ritz method is proposed and adopted, such as the dynamic characteristics of the jacket platform can be solved more efficiently without a need to examine the modes of vibration. The proposed analytical method also provides a more …


Constraint-Type Fictitious Time Integration Method For Solving Non-Linear Multi-Dimensional Elliptic Partial Differential Equations, Yung-Wei Chen, Chein-Shan Liu, Yen-Shen Chang, Jiang-Ren Chang Jun 2020

Constraint-Type Fictitious Time Integration Method For Solving Non-Linear Multi-Dimensional Elliptic Partial Differential Equations, Yung-Wei Chen, Chein-Shan Liu, Yen-Shen Chang, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

In this paper, we propose a constraint-type fictitious time integration method (FTIM) for solving multi-dimensional non-linear elliptic-type partial differential equations. Based on the variable transformation of FTIM, the original governing equation is transformed into a new parabolic equation of an evolution type by introducing a space-time variable, and a new time integration direction is obtained. However, the space-time variable depends on the governing equation, boundary condition and fictitious time variable, especially due to the nonlinear effect. Previous studies have not discussed the definition of these nonlinear parameter problems, which may result in severe numerical instability and inaccuracy. To completely overcome …


Recent Shrinkage And Fragmentation Of Bluegrass Landscape In Kentucky, Bo Tao, Yanjun Yang, Jia Yang, S. Ray Smith, James F. Fox, Alex C. Ruane, Jinze Liu, Wei Ren Jun 2020

Recent Shrinkage And Fragmentation Of Bluegrass Landscape In Kentucky, Bo Tao, Yanjun Yang, Jia Yang, S. Ray Smith, James F. Fox, Alex C. Ruane, Jinze Liu, Wei Ren

Plant and Soil Sciences Faculty Publications

The Bluegrass Region is an area in north-central Kentucky with unique natural and cultural significance, which possesses some of the most fertile soils in the world. Over recent decades, land use and land cover changes have threatened the protection of the unique natural, scenic, and historic resources in this region. In this study, we applied a fragmentation model and a set of landscape metrics together with the satellite-derived USDA Cropland Data Layer to examine the shrinkage and fragmentation of grassland in the Bluegrass Region, Kentucky during 2008–2018. Our results showed that recent land use change across the Bluegrass Region is …


About Fastening Cargo On The Wagon Under The Influence Of Transverse Forces, Yadgor Ozodovich Ruzmetov, Jamol Shihnazarov Jun 2020

About Fastening Cargo On The Wagon Under The Influence Of Transverse Forces, Yadgor Ozodovich Ruzmetov, Jamol Shihnazarov

Journal of Tashkent Institute of Railway Engineers

The content of the article is devoted to the incorrectness of the existing methodology for calculating freight fastening. Based on the conducted research, the article proved that the strength of freight fasteners subjected to transverse forces is not provided. The existing methodology for calculating freight fastenings, firstly, does not take into account the force of preliminary twists of the fastening wire, which increase the adhesion force of the freight to the car floor, and secondly, it does not take into account freight shifts that occur during transportation. The force in all wire fasteners subjected to transverse forces, depending on the …


Evaluation Of The Efficiency Of Diesel Locomotives On The Section Of Marokand - Kattakurgan Of Uzbek Railway, Oleg Sergeyevich Ablyalimov, Jasur Djura Ug'li Khodjiyev Jun 2020

Evaluation Of The Efficiency Of Diesel Locomotives On The Section Of Marokand - Kattakurgan Of Uzbek Railway, Oleg Sergeyevich Ablyalimov, Jasur Djura Ug'li Khodjiyev

Journal of Tashkent Institute of Railway Engineers

A comparative analysis of the efficiency of using diesel traction locomotives in the Marokand - Kattakurgan section of the Uzbek Railway for freight trains with and without stops at intermediate stations, siding and separate points is given. Mathematical models of conducting freight trains by diesel-powered locomotives were developed, specific resultant forces of the train were calculated and built in the modes of traction, idling and braking, curves of the speed of movement and time of the train on the considered real railway section. The kinematic parameters of the movement of freight trains and the main energy indicators of the transportation …


On The Development Of Mathematical Models Describing The Relationship Between The Parameters Of The Container Depot And Operation Technology, Daurenbek Ixtiyarovich Ilesaliev, Shaxboz Rovshan Ugli Abduvakhitov, Farrukh Kakhramonovich Azimov, Gulshanа Rasulovna Ibragimova Jun 2020

On The Development Of Mathematical Models Describing The Relationship Between The Parameters Of The Container Depot And Operation Technology, Daurenbek Ixtiyarovich Ilesaliev, Shaxboz Rovshan Ugli Abduvakhitov, Farrukh Kakhramonovich Azimov, Gulshanа Rasulovna Ibragimova

Journal of Tashkent Institute of Railway Engineers

Today, due to the increase in rail freight traffic, there is a shortage of containers, and the issue of shortage of containers has not been resolved for a long time. This substantiates the practical relevance of the study of container depots in railway transport. Connections with which the purpose of the article is to develop a methodology for the reliable determination of the most rational values of the parameters of the container terminal, thereby improving and increasing the level of customer service in transport in general.


Study Of The Influence Of An Alternating Magnetic Field On The Operation Of A Current Converter On The Magnetomodulation Effect, Abdurauf Malikovich Safarov, Sarvarbek Khamrayevich Jumaboyev Jun 2020

Study Of The Influence Of An Alternating Magnetic Field On The Operation Of A Current Converter On The Magnetomodulation Effect, Abdurauf Malikovich Safarov, Sarvarbek Khamrayevich Jumaboyev

Journal of Tashkent Institute of Railway Engineers

The paper proposes a design of a device for converting current to voltage with advanced functionality, designed to detect the asymmetry of three-phase currents in both DC and Made AC circuits. theoretical investigations and mathematical model of static characteristics of the Converter from changes in the magnetization curve of the magnetic material under the interaction of two fields generated by modulating current flowing in the modulation coil and an alternating magnetic field with a strength and created during the flow of DC buses DC field strength and shown that the nonlinearity of the dependence really is a principal factor responsible …


The Research Of Various Transient Processes In Current Transformers, Sultan Fayzullayevich Amirov, Shavkat Mukhsimov, Otabek Tashmuhammatovich Boltayev Jun 2020

The Research Of Various Transient Processes In Current Transformers, Sultan Fayzullayevich Amirov, Shavkat Mukhsimov, Otabek Tashmuhammatovich Boltayev

Journal of Tashkent Institute of Railway Engineers

In the article the transients occurring in current transformers are investigated and the values of secondary transient currents are determined using the operator's method with the help of a mathematical model of a wide-range current transformer using various primary sources. Using the obtained results, the regularities of secondary currents change over time are analyzed. It determined that, in the developed the wide-range current transformer, the influence of the aperiodic component of the primary current on the transformer current decreases with increasing the angle and creating a counter magnetomotive force in the core to expand the upper limit of the conversion …


Structural Scheme Of A Formalized Model Of The Process Of Accounting And Control Of Automation And Telemechanics Devices, D.Kh. Baratov, Nazirjhon Mukarramovich Aripov Jun 2020

Structural Scheme Of A Formalized Model Of The Process Of Accounting And Control Of Automation And Telemechanics Devices, D.Kh. Baratov, Nazirjhon Mukarramovich Aripov

Journal of Tashkent Institute of Railway Engineers

The article deals with the issues of functional support for the automated system of accounting and control of railway automation and telemechanics devices: signaling, centralization and blocking; presents the components of the electronic Executive part of the system; offers a conceptual model and describes the design features of the developed automated system.


Application Of The Volterra Tray Model In Solving The Problems Of Optimizing The Supply Of Grain Elevators By Wagons, Nazirjhon Mukarramovich Aripov, Daurenbek Ixtiyarovich Ilesaliev Jun 2020

Application Of The Volterra Tray Model In Solving The Problems Of Optimizing The Supply Of Grain Elevators By Wagons, Nazirjhon Mukarramovich Aripov, Daurenbek Ixtiyarovich Ilesaliev

Journal of Tashkent Institute of Railway Engineers

Ensuring uniform supply of wagons for loading and unloading of goods is one of the main tasks of the transport process. Existing methods for solving the issues of ensuring the rhythmicity of the supply of wagons for loading grain often do not allow us to identify the causes of the technological shortage of wagons. In this regard, in the framework of this work, the aim of the study is to increase the efficiency of the organization of providing grain elevators with wagons using models.


Developing Open Source Software Using Version Control Systems: An Introduction To The Git Language For Documenting Your Computational Research, Jared D. Smith, Jonathan D. Herman Jun 2020

Developing Open Source Software Using Version Control Systems: An Introduction To The Git Language For Documenting Your Computational Research, Jared D. Smith, Jonathan D. Herman

All ECSTATIC Materials

Version control systems track the history of code as it is committed (saved) by any number of developers. Have you made a coding error and cannot debug it? Version control systems allow for resetting code back to when it worked, and show what code has changed since previous commits.

The contents of this lecture provide an introduction to the git version control language, GitHub for cloud hosting open source code repositories, and tutorials that demonstrate common and useful git and GitHub practices. This lecture is intended to be coupled with a discussion on creating reproducible computational research.

The zipped folder …


Surface Modifications Of Reverse Osmosis Membranes For Removal Of Bromide And Reduction Of Fouling, Joseph Seo Jun 2020

Surface Modifications Of Reverse Osmosis Membranes For Removal Of Bromide And Reduction Of Fouling, Joseph Seo

Master's Theses

Reverse osmosis (RO) is widely used for water reuse and desalination. Although RO membranes are known for their high salt rejection and practical permeate flux, their performance can be impaired by fouling, and their removal of some disinfection byproducts and their precursors (e.g., bromide, N-Nitrosodimethylamine [NDMA]) does not meet drinking water standards. RO membrane modifications have been widely studied to overcome these limitations. In this research, RO membranes were grafted with cationic polymers to induce a positive charge on the RO membrane surface. This modification aimed at enhancing the rejection of negatively charged bromide ions by removing them from solution …


Sacrificial Piles As Scour Countermeasures In River Bridges A Numerical Study Using Flow-3d, Mohammad Nazari-Sharabian, Aliasghar Nazari-Sharabian, Moses Karakouzian, Mehrdad Karami Jun 2020

Sacrificial Piles As Scour Countermeasures In River Bridges A Numerical Study Using Flow-3d, Mohammad Nazari-Sharabian, Aliasghar Nazari-Sharabian, Moses Karakouzian, Mehrdad Karami

Civil and Environmental Engineering and Construction Faculty Research

Scour is defined as the erosive action of flowing water, as well as the excavating and carrying away materials from beds and banks of streams, and from the vicinity of bridge foundations, which is one of the main causes of river bridge failures. In the present study, implementing a numerical approach, and using the FLOW-3D model that works based on the finite volume method (FVM), the applicability of using sacrificial piles in different configurations in front of a bridge pier as countermeasures against scouring is investigated. In this regard, the numerical model was calibrated based on an experimental study on …


Rainfall Manipulation Experiments As Simulated By Terrestrial Biosphere Models: Where Do We Stand?, Athanasios Paschalis, Simone Fatichi, Jakob Zscheischler, Philippe Ciais, Michael Bahn, Lena Boysen, Jinfeng Chang, Martin De Kauwe, Marc Estiarte, Daniel Goll, Paul J. Hanson, Anna B. Harper, Enqing Hou, Jaime Kigel, Alan K. Knapp, Klaus S. Larsen, Wei Li, Sebastian Lienert, Yiqi Luo, Patrick Meir, Julia E.M.S. Nabel, Romà Ogaya, Anthony J. Parolari, Changhui Peng, Josep Peñuelas, Julia Pongratz, Serge Rambal, Inger K. Schmidt, Hao Shi, Marcelo Sternberg, Hanqin Tian, Elisabeth Tschumi, Anna Ukkola, Sara Vicca, Nicolas Viovy, Ying-Ping Wang, Zhuonan Wang, Karina Williams, Donghai Wu, Qiuan Zhu Jun 2020

Rainfall Manipulation Experiments As Simulated By Terrestrial Biosphere Models: Where Do We Stand?, Athanasios Paschalis, Simone Fatichi, Jakob Zscheischler, Philippe Ciais, Michael Bahn, Lena Boysen, Jinfeng Chang, Martin De Kauwe, Marc Estiarte, Daniel Goll, Paul J. Hanson, Anna B. Harper, Enqing Hou, Jaime Kigel, Alan K. Knapp, Klaus S. Larsen, Wei Li, Sebastian Lienert, Yiqi Luo, Patrick Meir, Julia E.M.S. Nabel, Romà Ogaya, Anthony J. Parolari, Changhui Peng, Josep Peñuelas, Julia Pongratz, Serge Rambal, Inger K. Schmidt, Hao Shi, Marcelo Sternberg, Hanqin Tian, Elisabeth Tschumi, Anna Ukkola, Sara Vicca, Nicolas Viovy, Ying-Ping Wang, Zhuonan Wang, Karina Williams, Donghai Wu, Qiuan Zhu

Civil and Environmental Engineering Faculty Research and Publications

Changes in rainfall amounts and patterns have been observed and are expected to continue in the near future with potentially significant ecological and societal consequences. Modelling vegetation responses to changes in rainfall is thus crucial to project water and carbon cycles in the future. In this study, we present the results of a new model‐data intercomparison project, where we tested the ability of 10 terrestrial biosphere models to reproduce the observed sensitivity of ecosystem productivity to rainfall changes at 10 sites across the globe, in nine of which, rainfall exclusion and/or irrigation experiments had been performed. The key results are …


Analysis And Optimization Of Colorimetric Nanosensors For Rapid Detection Of Microbes In Water, Ruby A. Lang Jun 2020

Analysis And Optimization Of Colorimetric Nanosensors For Rapid Detection Of Microbes In Water, Ruby A. Lang

Master's Theses

Access to safe water is a basic human right recognized by the United Nations General Assembly in 2010 (WHO, 2020). However, a least 2.2 billion people globally still are without safely managed water services meaning they use a drinking water source that can be contaminated with faeces (WHO, 2020). With such a pressing global health issue, it is clear that improvement to water systems is important and required in the Agenda 2030 Sustainable Development Goals (SDGs). However, to improve water systems and prove they are safe water sources, water quality testing must occur. A solution to this issue is the …


The Effect Of Climate Change On Groundwater Recharge In The United Arab Emirates, Yuliya Fadlallah Saade Jun 2020

The Effect Of Climate Change On Groundwater Recharge In The United Arab Emirates, Yuliya Fadlallah Saade

Civil and Environmental Theses

Climate change is impacting ecosystems and the water resources by causing temperature variation. Evapotranspiration rates are increasing when the temperature is high whereas, precipitation amount and intensity are varying based on geographical locations.

This change in precipitation has an inevitable impact on the groundwater recharge. Quantification of groundwater recharge is a prerequisite for efficient and sustainable groundwater resources management in arid regions.

Although, both surface and groundwater resources in the United Arab Emirates (UAE) are scarce; the anticipated climate change impacts could make these resources even scarcer. As such, the main aim of this thesis is to assess the potential …


Log Truck Value Analysis From Increased Rail Usage, Sangpil Ko, Pasi Lautala, Kuilin Zhang Jun 2020

Log Truck Value Analysis From Increased Rail Usage, Sangpil Ko, Pasi Lautala, Kuilin Zhang

Michigan Tech Publications, Part 1

Over the past several decades, the transportation of raw materials (logs) has increasingly shifted from the railway to trucks. However, the long-term sustainability of this shift is being questioned due to the shortage of truck drivers, fluctuation of fuel prices, and changes in hours of service laws. The industry is interested in the possibility to shift more logs back to the railway but the impact of such a shift on truckers has not been investigated. This study attempted to quantify the impact of such a change on the operations of log truckers by calculating time efficiency (percentage of daily hours …


Design Of Structural Stand For High-Precision Optics Microscopy, Sara T. Novell Jun 2020

Design Of Structural Stand For High-Precision Optics Microscopy, Sara T. Novell

Master's Theses

Lawrence Livermore National Lab (LLNL) is home to the National Ignition Facility (NIF), the world’s largest and most energetic laser. Each of the 192 beamlines contains dozens of large optics, which require offline damage inspection using large, raster-scanning microscopes. The primary microscope used to measure and characterize the optical damage sites has a precision level of 1 µm. Mounted in a class 100 clean room with a raised tile floor, the microscope is supported by a steel stand that structurally connects the microscope to the concrete ground. Due to ambient vibrations experienced in the system, the microscope is only able …


Modeling Artificial Groundwater Recharge In The Santa Rosa Creek Watershed, Alexander J. Murray Jun 2020

Modeling Artificial Groundwater Recharge In The Santa Rosa Creek Watershed, Alexander J. Murray

Master's Theses

The Santa Rosa Creek Watershed is an approximately 48 mi2 large watershed located on the central coast of California. This watershed drains to the Pacific Ocean through Santa Rosa Creek as it passes through agricultural land and the town of Cambria. Historically the groundwater within the Santa Rosa Creek Watershed has been used for irrigation, municipal and domestic uses, and the creek is critical habitat steelhead trout. During dry years, there is less water for all uses. When low groundwater levels occur, water can be drawn out of the creek and into the soil, drying out steelhead habitat. Seven agricultural …


A Comparative Study On Seismic Analysis Methods And The Response Of Systems With Classical And Nonclassical Damping, Noah G. Bleichner Jun 2020

A Comparative Study On Seismic Analysis Methods And The Response Of Systems With Classical And Nonclassical Damping, Noah G. Bleichner

Master's Theses

This thesis investigated the application of seismic analysis methods and the response of idealized shear frames subjected to seismic loading. To complete this research, a Design Basis Earthquake (DBE) for a project site in San Luis Obispo, CA, and five past earthquake records were considered. The DBE was produced per the American Society of Civil Engineers’ Minimum Design Loads for Buildings and Other Structures (ASCE 7-10) and used for application of the Equivalent Lateral Force Procedure (ELFP) and Response Spectrum Analysis (RSA). When applying RSA, the modal peak responses were combined using the Absolute Sum (ABS), Square-Root-of-the-Sum-of-Squares (SRSS), and Complete …