Digital Commons Network^™

Wave Climate Associated With Changing Water Level And Ice Cover In Lake Michigan, Chenfu Huang, Longhuan Zhu, Gangfeng Ma, Guy A. Meadows, Pengfei Xue

Civil & Environmental Engineering Faculty Publications

Detailed knowledge of wave climate change is essential for understanding coastal geomorphological processes, ecosystem resilience, the design of offshore and coastal engineering structures and aquaculture systems. In Lake Michigan, the in-situ wave observations suitable for long-term analysis are limited to two offshore MetOcean buoys. Since this distribution is inadequate to fully represent spatial patterns of wave climate across the lake, a series of high-resolution SWAN model simulations were performed for the analysis of long-term wave climate change for the entirety of Lake Michigan from 1979 to 2020. Model results were validated against observations from two offshore buoys and 16 coastal …

Characterizing Seagrass Effects On Hydrodynamics Of Waves And Currents Through Field Measurements And Computational Modelling, Ramin Familkhalili, Navid Tahvildari

Civil & Environmental Engineering Faculty Publications

Low-lying coastal and estuarine areas are among the most populated regions globally, have high economic significance, and are increasingly threatened by climate change, sea level rise, nuisance flooding, and extreme storms. Nature-based coastal protections are sustainable and sea-level resilient alternatives compared to traditional solutions such as dikes and seawalls. Submerged aquatic vegetation (SAV) or seagrasses can provide coastal flood and erosion protection by attenuating storm wave and current energy and stabilizing seabed sediments. However, more research is needed to understand the interactions between flow, SAVs, and sediments. These dynamic interactions affect flow at different scales and seagrass productivity. In this …

Effects Of Hydrological And Climatic Variables On Cyanobacterial Blooms In Four Large Shallow Lakes Fed By The Yangtze River, Jian Huang, Qiujin Xu, Xixi Wang, Hao Ji, Edward J. Quigley, Mohamadali Sharbatmaleki, Simeng Li, Beidou Xi, Biao Sun, Caole Li

Civil & Environmental Engineering Faculty Publications

Shallow lakes, one of the most widespread water bodies in the world, are easily shifted to a new trophic state due to external interferences. Shifting hydrologic conditions and climate change can cause cyanobacterial harmful algal blooms (CyanoHABs) in shallow lakes, which pose serious threats to ecological integrity and human health. This study analyzed the effects of hydrologic and meteorological variables on cyanobacterial blooms in Yangtze-connected lakes (Lake Dongting and Poyang) and isolated lakes (Lake Chao and Tai). The results show that (i) chlorophyll-a (Chl-a) concentration tends to decrease exponentially with increasing relative lake level fluctuations (RLLF) and precipitation, but to …

Applications Of Membranes For Sustainability, Veeriah Jegatheesan, Chettiyappan Visvanathan, Li Shu, Faisal I. Hai, Ludovic F. Dumée

Research outputs 2014 to 2021

Applications of membranes in water and wastewater treatment, desalination, as well as other purification processes, have become more widespread over the past few decades. However, we continue to ponder on (i) how well do we get maximum benefits from membrane applications? (ii) In what areas of membranes do we need to further our fundamental understanding? (iii) Which membrane technologies find difficulties in scale-up? (iv) How good are we in integrating membrane technologies? (v) How can we improve the reliability of membranes and reduce the cost? (vi) Where are we in disseminating the needs if we are to use membranes all …

Neutron Scattering: A Subsurface Application Review, Mirhasan Hosseini, Muhammad Arif, Alireza Keshavarz, Stefan Iglauer

Research outputs 2014 to 2021

Geomaterials and filling fluids properties that are pertinent to a geologic porous media can be characterized using a range of methods, such as nuclear magnetic resonance, X-rays, infrared spectroscopy, and neutron scattering (NS). In this context, NS features as an important tool elucidate key properties of a porous medium, which has recently gained significant attention. Key rock properties that can be measured by NS include: rock texture (i.e. crystallographic preferred orientation), mechanical properties (i.e. stress and strain) as well as porous medium properties (pore porosity, pore size and connectivity). In addition, NS imaging can help elucidate the phase behaviour of …

Online Bus Speed Prediction With Spatiotemporal Interaction: A Laplace Approximation-Based Bayesian Approach, Haipeng Cui, Kun Xie, Bin Hu, Hangfei Lin

Civil & Environmental Engineering Faculty Publications

This study proposes a novel Bayesian hierarchical approach for online bus speed prediction by explicitly accounting for the spatiotemporal interaction (STI) of speed observations. The use of Laplace approximation can expedite the estimation of Bayesian models and enable the implementation of online prediction. Large numbers of trials are carried out to identify significant predictors and the optimal length of the look-back time window to achieve the highest prediction accuracy. The spatiotemporal interacting patterns are also explored, and results show that the Type IV model assuming the structured spatial effect interacts with the structured temporal effect can best accommodate the bus …

Exploring And Visualizing Spatial Effects And Patterns In Ride-Sourcing Trip Demand And Characteristics, Bishoy Kelleny, Sherif Ishak

Civil & Environmental Engineering Faculty Publications

The complex demand pattern of ride-sourcing remains to be a challenge to transportation modeling practitioners due to the infancy and the inherently dynamic nature of the ride-sourcing system. Spatial effects exploration and analysis protocols can provide informative insights on the underlying structure of demand and trip characteristics. Those protocols can be thought of as an opportunistic strategy to alleviate the complexity and help specifying the appropriate econometric models for the system. Spatial effects exploration is comparable to point pattern analysis, in which, signals from spatial entities, like census tracts, can be analyzed statistically to reveal whether a specific phenomenon respective …

Workshop Outcomes Report: 1st International Workshop On Seismic Resilience Of Arctic Infrastructure And Social Systems, Majid Ghayoomi, Katharine Duderstadt, Alexander Kholodov, Alexander Shiklomanov, Matthew Turner, Elham Ajorlou

Faculty Publications

No abstract provided.

Assessment Of Cu(In, Ga)Se₂ Solar Cells Degradation Due To Water Ingress Effect On The Cds Buffer Layer, Deewakar Poudel, Benjamin Belfore, Shankar Karki, Grace Rajan, Sina Soltanmohammad, Angus Rockett, Sylvain Marsillac

Electrical & Computer Engineering Faculty Publications

The effect of water ingress on the surface of the buffer layer of a Cu(In, Ga)Se2 (CIGS) solar cell was studied. Such degradation can occur either during the fabrication process, if it involves a chemical bath as is often the case for CdS, or while the modules are in the field and encapsulants degrade. To simulate the impact of this moisture ingress, devices with a structure sodalime glass/Mo/CIGS/CdS were immersed in deionized water. The thin films were then analyzed both pre and post water soaking. Dynamic secondary ion mass spectroscopy (SIMS) was performed on completed devices to analyze impurity diffusion …

Mapping Michigan's Historic Coastlines, Ryan A. Williams

Dissertations, Master's Theses and Master's Reports

This five-year project, sponsored by the Michigan Department of Environment, Great Lakes, and Energy, is working to map how Michigan’s Great Lakes shorelines have changed over the past 80+ years. Products of this project include publicly available digital, georeferenced, historic aerial photography datasets, as well as map layers depicting the locations of historic shorelines and bluff lines from 1938, 1980, 2009, 2016, 2018, and 2020. Additional products include bluff retreat risk areas, shoreline rate of change map layers, and tools to assist in the development of future Coastal Vulnerability Index projects for the Great Lakes. All products are available as …

Analytical Assessment Of Project Complexity: A Guide To Managing Projects Through Reduction Of Complexity, Christopher Vanarsdale

Dissertations, Master's Theses and Master's Reports

This research discusses the characteristics that make projects difficult to manage. Project inefficiencies and failures can be attributed to the structure of a system. Developing a measurement for complexity based on the number and nature of interactions in the system can allow project complexity to be reduced while still meeting project objectives. Previous research has identified characteristics or markers of complex systems but does not address how to measure or how to reduce a system’s complexity.

The objective of this dissertation is to develop a metric for complexity that assists project and emergency managers in reducing project complexity either by …

Predicting The Impacts Of Climate Change On The Great Lakes Water Levels Using A Fully Coupled 3d Regional Modeling System, Miraj Kayastha

Dissertations, Master's Theses and Master's Reports

The Great Lakes of North America are the largest surface freshwater system in the world and many ecosystems, industries, and coastal processes are sensitive to the changes in their water levels. The recent changes in the Great Lakes climate and water levels have particularly highlighted the importance of water level prediction. The water levels of the Great Lakes are primarily governed by the net basin supplies (NBS) of each lake which are the sum of over-lake precipitation and basin runoff minus lake evaporation. Recent studies have utilized Regional Climate Models (RCMs) with a fully coupled one-dimensional (1D) lake model to …

Case Study Of Gravity-Fed Mountain Spring Tap System In Ha Leronti, Lesotho, Africa, Sarah Peterson

Dissertations, Master's Theses and Master's Reports

Water security has been declining rapidly in Lesotho, Africa in recent years. Lack of water has led to food insecurity, livestock deaths, and the spread of disease. Rural Basotho depend on rainfall to sustain their livelihoods; however, precipitation variability has recently increased due to climate change. For those who reside in the highlands of Lesotho, mountain springs can be a clean source of water. The tap system in the village of Ha Leronti relies on gravity to distribute water from two mountain springs to the ten village taps and nearby school campus. However, it is incapable of transporting the basic …

A Deep Machine Learning Approach For Predicting Freeway Work Zone Delay Using Big Data, Abdullah Shabarek

Dissertations

The introduction of deep learning and big data analytics may significantly elevate the performance of traffic speed prediction. Work zones become one of the most critical factors causing congestion impact, which reduces the mobility as well as traffic safety. A comprehensive literature review on existing work zone delay prediction models (i.e., parametric, simulation and non-parametric models) is conducted in this research. The research shows the limitations of each model. Moreover, most previous modeling approaches did not consider user delay for connected freeways when predicting traffic speed under work zone conditions. This research proposes Deep Artificial Neural Network (Deep ANN) and …

High-Speed Rail Safety Analysis Based On Dual-Weighted Complex Network, Liu Lv

Dissertations

This study uses a complex network model to analyze the causes of accidents in high-speed railway operations. By identifying the key factors that led to high-speed railway accidents, hidden safety hazards were discovered. This will help improve the operational safety of the U.S. high-speed rail line under construction.

The analysis uses the regional high-speed railway network in Guangzhou, China as a case study, including the railway (including high-speed railway) accidents that occurred in the company's jurisdiction from 2013 to 2017. With comparative analysis between general railways and high-speed railways, the changes of high-speed railway safety factors are explored. Data analysis …

Characterizing Reactive Iron Mineral Coatings And Their Roles In Natural Attenuation At A Site With Historical Contamination, Han Hua

Dissertations

Reactive iron mineral coatings in redox transition zones play an important role in contaminant attenuation. These mineral coatings include poorly crystalline to crystalline iron sulfides, carbonates, and oxyhydroxides, and are a signature of the biogeochemical processes occurring. To better understand these processes, reactive iron mineral coatings are characterized in an 18-m Anaerobic Core collected from a contaminated industrial site. This study targets redox transition zones uncovered in the core. A suite of complementary analyses is applied to distinguish the surface coating mineralogy using X-ray Diffraction, X-ray fluorescence, and field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray analyzer (EDX). In …

Direct Predictive Speed Control Of Salient Pmsm Drives In Constant Torque And Constant Power Regimes For Electric Vehicles Applications, Francis Mwasilu

Tanzania Journal of Engineering and Technology (TJET)

A direct speed control of salient permanent magnet synchronous motor (PMSM) drives in constant torque and constant power regimes for electric vehicles applications is presented. The proposed speed control scheme is derived from model predictive control approach where both rotor speed and stator current are formulated in a single objective function that is periodically computed to attain the PMSM drive optimum switching states. The dynamic model of the PMSM intrinsically encompasses the unknown disturbance, which should be rejected for high-performance speed control especially in transient conditions. Consequently, the extended modified augmented state Kalman filter (ASKF) is incorporated in the proposed …

Nebraska Rail Crossing Safety Research, Aemal Khattak, Yashu Kang, Huiyuan Liu

Nebraska Department of Transportation: Research Reports

The research objectives of this project were to update Nebraska Department of Transportation (NDOT) 1999 Nebraska Accident Prediction Model for Highway-Rail Grade Crossings (HRGCs) and to develop guidelines using Lancaster County Nebraska HRGCs for improving safety at urban gated HRGCs that are not designated quiet zones but are in the vicinity of quiet zone crossings.

FRA crash and HRGC inventory data were utilized for estimation of the new model after inventory information on 742 HRGCs was updated. HRGC crashes for 2008-2018 period were used for model estimation while 2019 HRGC crashes were used for model prediction validation. After consideration of …

2020 Scholarly Productivity Report, Missouri University Of Science And Technology

Civil, Architectural and Environmental Engineering Scholarly Productivity Reports

No abstract provided.

Results Of A Numerical Study Of Currents In The Vicinity Of A Damless Water Intake, D.R. Bazarov, O.F. Vokhidov, M. Tashkhanova, F. Uljayev

Irrigation and Melioration

The problem of sustainable water intake in the conditions of significant fluctuations of flow rates and water level is significantly exacerbated by erosion of river beds. A typical example of such conditions is the damless water intake into the Karshi Main Canal (KMC) where the main flow of the Amudarya river continuously moves along a wide floodplain, changing the direction of currents. As a result, it is very difficult to withdraw the required volume of water from the river to the canal especially during dry years due to the high instability of currents at the entrance to the canal. Within …

Experimental Bases Of Determining The Hydraulic Friction Coefficient In Preasure Systems Fo Sediment Flow, A.M. Arifjanov, Q.Т. Rahimov, A.D. Abduraimova, S.N. Xoshimov

Irrigation and Melioration

When the fluid moves in pressure pipelines, the determination of the coefficient of hydraulic friction is very important. To determine the coefficient of hydraulic friction during the movement of a homogeneous fluid, there are formulas that have a theoretical basis and experimental confirmation. Determination of the coefficient of hydraulic friction is much more complicated when there is a turbid flow in the pipeline, in such cases laboratory experiments are necessary. The article deals with the issue of experimental determination of the coefficient of hydraulic friction during the movement of slurry in pressure systems. The experimental results are processed based on …

Forecasting The Dynamics Of Cotton Yield In The Ferghana Region, V. Vakhobov, А.А. Faiziev

Irrigation and Melioration

Observations of a certain phenomenon, the nature of which changes over time, give rise to an ordered sequence, which is called a time series. In the article, using the method of statistical time series analysis, statistical pattern of time series Y₁ – average yield of cotton in Fergana region of the Republic of Uzbekistan(on materials of CSB of the Republic of Uzbekistan for 1991-2018 years). Point and interval estimates for the average cotton yield were constructed with a 95% guarantee, explicit types of trends were determined, and the yield in the region was predicted for subsequent years. Using statistical …

Hydraulic Elevator For Purification Of Water Supply Facilities Of The Reservoir, R.R. Ergashev, F. Atrikbekova, H. Khusanboeva, B.T. Kholbutaev, N.A. Babazhanov

Irrigation and Melioration

The purpose of the research is to increase the efficiency of pumping stations operation by improving the methods of uniform flow spreading in the front chamber and inlet of the pumping station and developing constructive measures to improve the hydraulic conditions for supplying the flow to the pumps. The improvement of the method of hydraulic calculation of the flow in the front chamber and the water intake chamber is given on the example of the head pumping station of the Jizzakh cascade. In the process of research, standard methods of full-scale and bench tests of pumps, methods of mathematical and …

Traction Control Of The Friction Drive Of The Vertical Spindle, M. Shoumarova, T. Abdillaev, Sh.A. Yusupov, Ch.A. Shermatova

Irrigation and Melioration

The main indicator in assessing the quality of the work of cotton pickers is its completeness of picking cotton, among the factors that predetermine the completeness of picking a special place is occupied by the direction and magnitude of the absolute speed of the spindle tooth. Among the factors affecting the absolute speed of the tooth, the main place is occupied by the angular speed of rotation of the spindle around its own axis, which depends on the quality of functioning of the friction drive of the spindle. This drive does not always provide its required traction capacity, since due …

Theoretical Research On Determining The Length Of The Shovels Of A Wheel Of Centrifugal Fans, V.A. Arkhipov, D. Dzhuraev, I.Zh. Toirov, A.E. Urishev

Irrigation and Melioration

Presents the results of theoretical research by scientists, carried out scientific work to determine the length of the shovel of a centrifugal fan wheel. A technological scheme for installing a shovel on a fan wheel disk has been developed Analyzes of these works are carried out, which show that the length of the wheel shovel has a significant dependence on the parameters of the wheel (R, R₁), the angle of installation α and the radius of the arc R₃ of the shovel. An analytical dependence is derived for determining the length of the shovel of a …

An Assessment Of Research Trends On Fiscal Policy, Shabir Hussain Khahro, Shoail Farooq, Tauha Hussain Ali Dr, Nafees Ahmed Memon Dr, Qasim Hussain Khahro

Library Philosophy and Practice (e-journal)

Fiscal policy has been a topic of research interest for researchers. It plays a very important role in the economic growth of any country. Fiscal policy does not only achieve economic development, but eliminates the hindrances that assist economic stability. Based on the significance of the term. This paper evaluates the research output of the term fiscal policy since 1970 in different fields using the Scopus database. The data was collected from the Scopus database and were analyzed using Microsoft Excel to analyze the research trends on fiscal policy. It is concluded that fiscal policy has been a topic of …

The Impact Of Grinding Time On Properties Of Cement Mortar Incorporated High Volume Waste Paper Sludge Ash, Ali A. Shubbar, Monower Sadique, Mohammed S. Nasr, Zainab S. Al-Khafaji, Khalid S. Hashim

Karbala International Journal of Modern Science

Cement is considered a base material in preparing blending mixtures that applying in various projects in the civil engineering field. Nevertheless, the cement production process cause indubitable negative environmental influences such as emitting CO₂. The production of cement produces around 7% of the global CO₂ emissions. Thus, searching for alternate binders in building processes to minimise or substitute cement has been one of the social problems. A by-product or waste products are among the potential alternatives to the mentioned problem. The present investigation involves the consumption of paper sludge ash (PSA) waste as cement replacement to produce …

Laboratory Testing And Mechanistic Analysis Of Treated Subgrade Soils, Hari Kumar Reddy Yarrapureddi

Civil Engineering Theses

Calcium-based stabilizing agents such as cement and lime have been extensively used to improve the engineering properties of base and subgrade layers of pavement systems. Recently, polymers and chemical stabilizers have become popular due to cost efficiency, ease of application, and fast curing times. In this study, California Bearing Ratio (CBR) values of polymer and chemical treated soils were compared with the CBR values of soils treated with conventional stabilizers. Parametric sensitivity analyses was carried out on key parameters including the type of subgrade soil, stabilizing agent, stabilizing agent treatment levels, and moisture conditioning. Additionally, numerical analyses was performed to …

Policy Changes Impact In Deforestation Of The Brazilian Amazon, Iara Silva Jaques

Master's Projects and Capstones

Since discovered and inhabited, the Brazilian Amazon has been explored and impacted negatively by human activities. The conversion of forest to pastureland and farmland, as well as mining activities, road opening, wood and ore extraction and fire are historically the main causes of environmental damages and forest loss in the region. This project overviewed the latest changes in environmental policy and practices towards environmental protection conducted by the Brazilian president Jair Bolsonaro, since he took office in 2019, and analyzed the progress of deforestation in the recent years under the new federal administration. Geographic Information System analysis were used to …

Relationships Between In-Situ Tests And Soil Cyclic Strength For Earthquake Hazard Characterization In The Pacific Northwest, Tanner Scott Bryantt

Dissertations and Theses

Strong earthquake shaking is a natural hazard threat in the Pacific Northwest. Soil failure due to strong earthquake shaking -- known as cyclic soil failure or liquefaction -- is expected to cause large ground deformations and damage to roads, bridges, and other civil infrastructure. Cyclic soil strength (CRR) is often characterized with in-situ geotechnical tests including the cone penetration test (CPT). Relationships between CRR and in-situ test data are not well established for soils in the Pacific Northwest. Portland State University, in partnership with New Albion Geotechnical has compiled a database of cyclic lab tests for Pacific Northwest soils to …