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Full-Text Articles in Physical Sciences and Mathematics

Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq Mar 2024

Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq

Faculty Publications

Rainfed agriculture is the mainstay of economies across Southern Africa (SA), where most precipitation is received during the austral summer monsoon. This study aims to further our understanding of monsoon precipitation predictability over SA. We use three natural climate forcings, El Niño–Southern Oscillation, Indian Ocean Dipole (IOD), and the Indian Ocean Precipitation Dipole (IOPD)—the dominant precipitation variability mode—to construct an empirical model that exhibits significant skill over SA during monsoon in explaining precipitation variability and in forecasting it with a five-month lead. While most explained precipitation variance (50%–75%) comes from contemporaneous IOD and IOPD, preconditioning all three forcings is key …


Speciation Of Elements Via A Sequential Extraction Procedure In Municipal Wastewater Biosolids From Three Rural Wwtp In East Texas (Usa), Kefa K. Onchoke Aug 2023

Speciation Of Elements Via A Sequential Extraction Procedure In Municipal Wastewater Biosolids From Three Rural Wwtp In East Texas (Usa), Kefa K. Onchoke

Faculty Publications

In this data article, the bioavailability of elements in municipal wastewater sludge (also known as biosolids) in samples collected from three treatment plants in East Texas, USA was evaluated. Although detailed speciation of the metals were assessed by using inductively coupled plasma optical spectroscopy (ICP-OES), and were discussed in the research article titled “Evaluating bioavailability of elements in municipal wastewater sludge (Biosolids) from three rural wastewater treatment plants in East Texas (USA) by a sequential extraction procedure” [1], this report presents the absolute raw concentrations and fractionations of the 26 metals from the biosolids (Nacogdoches Wastewater Sludge, Lufkin Wastewater Sludge, …


The Traded Water Footprint Of Global Energy From 2010 To 2018, Christopher M. Chini, Rebecca A. M. Peer Jan 2021

The Traded Water Footprint Of Global Energy From 2010 To 2018, Christopher M. Chini, Rebecca A. M. Peer

Faculty Publications

The energy-water nexus describes the requirement of water-for-energy and energy-for-water. The consumption of water in the production and generation of energy resources is also deemed virtual water. Pairing the virtual water estimates for energy with international trade data creates a virtual water trade network, facilitating analysis of global water resources management. In this database, we identify the virtual water footprints for the trade of eleven different energy commodities including fossil fuels, biomass, and electricity. Additionally, we provide the necessary scripts for downloading and pairing trade data with the virtual water footprints to create a virtual water trade network. The resulting …


A Review Of Energy-For-Water Data In Energy-Water Nexus Publications, Christopher M. Chini, Lauren E. Excell, Ashlynn S. Stillwell Jan 2021

A Review Of Energy-For-Water Data In Energy-Water Nexus Publications, Christopher M. Chini, Lauren E. Excell, Ashlynn S. Stillwell

Faculty Publications

Published literature on the energy-water nexus continues to increase, yet much of the supporting data, particularly regarding energy-for-water, remains obscure or inaccessible. We perform a systematic review of literature that describes the primary energy and electricity demands for drinking water and wastewater systems in urban environments. This review provides an analysis of the underlying data and other properties of over 170 published studies by systematically creating metadata on each study. Over 45% of the evaluated studies utilized primary data sources (data collected directly from utilities), potentially enabling large-scale data sharing and a more comprehensive understanding of global water-related energy demand. …


An Integrated Assessment Of The Global Virtual Water Trade Network Of Energy, Rebecca A. M. Peer, Christopher M. Chini Nov 2020

An Integrated Assessment Of The Global Virtual Water Trade Network Of Energy, Rebecca A. M. Peer, Christopher M. Chini

Faculty Publications

The global trade of energy allows for the distribution of the world's collective energy resources and, therefore, an increase in energy access. However, this network of trade also generates a network of virtually traded resources that have been used to produce energy commodities. An integrated database of energy trade water footprints is necessary to capture interrelated energy and water concerns of a globalized economy,and is also motivated by current climate and population trends. Here, we quantify and present the virtual water embedded in energy trade across the globe from 2012 to 2018, building on previous water footprinting and energy virtual …


Decision Agriculture, Abdul Salam, Usman Raza Aug 2020

Decision Agriculture, Abdul Salam, Usman Raza

Faculty Publications

In this chapter, the latest developments in the field of decision agriculture are discussed. The practice of management zones in digital agriculture is described for efficient and smart faming. Accordingly, the methodology for delineating management zones is presented. Modeling of decision support systems is explained along with discussion of the issues and challenges in this area. Moreover, the precision agriculture technology is also considered. Moreover, the chapter surveys the state of the decision agriculture technologies in the countries such as Bulgaria, Denmark, France, Israel, Malaysia, Pakistan, United Kingdom, Ukraine, and Sweden. Finally, different field factors such as GPS accuracy and …


Electromagnetic Characteristics Of The Soil, Abdul Salam, Usman Raza Aug 2020

Electromagnetic Characteristics Of The Soil, Abdul Salam, Usman Raza

Faculty Publications

The electromagnetic characteristics of the soil are discussed in this chapter. The characteristics of porous bedrock, soil medium, and impacts of rain attenuations are also presented. The models of dielectric soil properties are studied with a rigorous focus on the constitutive parameters of subsurface soil medium. Moreover, the permittivity and wavenumber in soil are explained. In addition, the frequency-dependent dielectric properties such as dispersion in soil, absorption characteristic, and penetration depth versus frequency are reviewed. Furthermore, the effective permittivity of soil–water mixture for through-the soil-propagation mechanism is analyzed thoroughly.


Underground Phased Arrays And Beamforming Applications, Abdul Salam, Usman Raza Aug 2020

Underground Phased Arrays And Beamforming Applications, Abdul Salam, Usman Raza

Faculty Publications

This chapter presents a framework for adaptive beamforming in underground communication. The wireless propagation is thoroughly analyzed to develop a model using the soil moisture as an input parameter to provide feedback mechanism while enhancing the system performance. The working of array element in the soil is analyzed. Moreover, the effect of soil texture and soil moisture on the resonant frequency and return loss is studied in detail. The wave refraction from the soil–air interface highly degrades the performance of the system. Furthermore, to beam steering is done to achieve high gain for lateral component improving the UG communication. The …


Signals In The Soil: An Introduction To Wireless Underground Communications, Abdul Salam, Usman Raza Aug 2020

Signals In The Soil: An Introduction To Wireless Underground Communications, Abdul Salam, Usman Raza

Faculty Publications

In this chapter, wireless underground (UG) communications are introduced. A detailed overview of WUC is given. A comprehensive review of research challenges in WUC is presented. The evolution of underground wireless is also discussed. Moreover, different component of UG communications is wireless. The WUC system architecture is explained with a detailed discussion of the anatomy of an underground mote. The examples of UG wireless communication systems are explored. Furthermore, the differences of UG wireless and over-the-air wireless are debated. Different types of wireless underground channel (e.g., In-Soil, Soil-to-Air, and Air-to-Soil) are reported as well.


Modulation Schemes And Connectivity In Wireless Underground Channel, Abdul Salam, Usman Raza Aug 2020

Modulation Schemes And Connectivity In Wireless Underground Channel, Abdul Salam, Usman Raza

Faculty Publications

In this chapter, a thorough treatment of the modulation schemes for UG Wireless is presented. The effects of soil texture and water content on the capacity of multi-carrier modulation in WUC are discussed. The multi-carrier capacity model results are analyzed. Moreover, the underground MIMO design for underground communications is explained thoroughly. An analysis of medium access in wireless underground is done as well. Furthermore, the soil properties are considered for cross-layer communications of UG wireless. The performance analysis of traditional modulation schemes is also considered. The soil moisture-based modulation approach is also explored in this chapter. The connectivity and diversity …


Underground Wireless Channel Bandwidth And Capacity, Abdul Salam, Usman Raza Aug 2020

Underground Wireless Channel Bandwidth And Capacity, Abdul Salam, Usman Raza

Faculty Publications

The UG channel bandwidth and capacity are vital parameters in wireless underground communication system design. In this chapter, a comprehensive analysis of the wireless underground channel capacity is presented. The impact of soil on return loss, bandwidth, and path loss is discussed. The results of underground multi-carrier modulation capacity are also outlined. Moreover, the single user capacity and multi-carrier capacity are also introduced with an in-depth treatment of soil texture, soil moisture, and distance effects on channel capacity. Finally, the chapter is concluded with a discussion of challenges and open research issues.


Signals In The Soil: Underground Antennas, Abdul Salam, Usman Raza Aug 2020

Signals In The Soil: Underground Antennas, Abdul Salam, Usman Raza

Faculty Publications

Antenna is a major design component of Internet of Underground Things (IOUT) communication system. The use of antenna, in IOUT, differs from traditional communication in that it is buried in the soil. Therefore, one of the main challenges, in IOUT applications, is to establish a reliable communication. To that end, there is a need of designing an underground-specific antenna. Three major factors that can impact the performance of a buried antenna are: (1) effect of high soil permittivity changes the wavelength of EM waves, (2) variations in soil moisture with time affecting the permittivity of the soil, and (3) difference …


Soil Moisture And Permittivity Estimation, Abdul Salam, Usman Raza Aug 2020

Soil Moisture And Permittivity Estimation, Abdul Salam, Usman Raza

Faculty Publications

The soil moisture and permittivity estimation is vital for the success of the variable rate approaches in the field of the decision agriculture. In this chapter, the development of a novel permittivity estimation and soil moisture sensing approach is presented. The empirical setup and experimental methodology for the power delay measurements used in model are introduced. Moreover, the performance analysis is explained that includes the model validation and error analysis. The transfer functions are reported as well for soil moisture and permittivity estimation. Furthermore, the potential applications of the developed approach in different disciplines are also examined.


Current Advances In Internet Of Underground Things, Abdul Salam, Usman Raza Aug 2020

Current Advances In Internet Of Underground Things, Abdul Salam, Usman Raza

Faculty Publications

The latest developments in Internet of Underground Things are covered in this chapter. First, the IOUT Architecture is discussed followed by the explanation of the challenges being faced in this paradigm. Moreover, a comprehensive coverage of the different IOUT components is presented that includes communications, sensing, and system integration with the cloud. An in-depth coverage of the applications of the IOUT in various disciplines is also surveyed. These applications include areas such as decision agriculture, pipeline monitoring, border control, and oil wells.


Signals In The Soil: Subsurface Sensing, Abdul Salam, Usman Raza Aug 2020

Signals In The Soil: Subsurface Sensing, Abdul Salam, Usman Raza

Faculty Publications

In this chapter, novel subsurface soil sensing approaches are presented for monitoring and real-time decision support system applications. The methods, materials, and operational feasibility aspects of soil sensors are explored. The soil sensing techniques covered in this chapter include aerial sensing, in-situ, proximal sensing, and remote sensing. The underlying mechanism used for sensing is also examined as well. The sensor selection and calibration techniques are described in detail. The chapter concludes with discussion of soil sensing challenges.


Autonomous Irrigation Management In Decision Agriculture, Abdul Salam, Usman Raza Aug 2020

Autonomous Irrigation Management In Decision Agriculture, Abdul Salam, Usman Raza

Faculty Publications

In this chapter, the important application of autonomous irrigation management in the field decision agriculture is discussed. The different types of sensor-guided irrigation systems are presented that includes center pivot systems and drip irrigation systems. Their sensing and actuator components are with detailed focus on real-time decision-making and integration to the cloud. This chapter also presents irrigation control systems which takes, as an input, soil moisture and temperature from IOUT and weather data from Internet and communicate with center pivot based irrigation systems. Moreover, the system architecture is explored where development of the nodes including sensing and actuators is presented. …


Variable Rate Applications In Decision Agriculture, Abdul Salam, Usman Raza Aug 2020

Variable Rate Applications In Decision Agriculture, Abdul Salam, Usman Raza

Faculty Publications

In this chapter, the variable rate applications (VRA) are presented for the field of decision agriculture. The characteristics of VRA control systems are described along with control hardware. Different types of VRA systems are discussed (e.g., liquid VRA systems and dry VRA systems). A case study is also explored in this regard. Moreover, recent advances and future trends are also outlined. Accordingly, a sustainable variable-rate irrigation scheduling is studied where different hardware and software component of the cyber-physical system are considered. Finally, chapter is concluded with a novel sensor deployment methodology.


Wireless Underground Channel Modeling, Abdul Salam, Usman Raza Aug 2020

Wireless Underground Channel Modeling, Abdul Salam, Usman Raza

Faculty Publications

A comprehensive treatment of wireless underground channel modeling is presented in this chapter. The impacts of the soil on bandwidth and path loss are analyzed. A mechanism for the UG channel sounding and multipath characteristics analysis is discussed. Moreover, novel time-domain impulse response model for WUC is reviewed with the explanation of model parameters and statistics. Furthermore, different types of the through-the-soil wireless communications are surveyed. Finally, the chapter concludes with discussion of the UG wireless statistical model and path loss model for through-the-soil wireless communications in decision agriculture. The model presented in this chapter is also validated with empirical …


Zenneck Waves In Decision Agriculture: An Empirical Verification And Application In Em-Based Underground Wireless Power Transfer, Usman Raza, Abdul Salam May 2020

Zenneck Waves In Decision Agriculture: An Empirical Verification And Application In Em-Based Underground Wireless Power Transfer, Usman Raza, Abdul Salam

Faculty Publications

In this article, the results of experiments for the observation of Zenneck surface waves in sub GHz frequency range using dipole antennas are presented. Experiments are conducted over three different soils for communications distances of up to 1 m. This empirical analysis confirms the existence of Zenneck waves over the soil surface. Through the power delay profile (PDP) analysis, it has been shown that other subsurface components exhibit rapid decay as compared to the Zenneck waves. A potential application of the Zenneck waves for energy transmission in the area of decision agriculture is explored. Accordingly, a novel wireless through-the-soil power …


Wireless Underground Communications In Sewer And Stormwater Overflow Monitoring: Radio Waves Through Soil And Asphalt Medium, Usman Raza, Abdul Salam Feb 2020

Wireless Underground Communications In Sewer And Stormwater Overflow Monitoring: Radio Waves Through Soil And Asphalt Medium, Usman Raza, Abdul Salam

Faculty Publications

Storm drains and sanitary sewers are prone to backups and overflows due to extra amount wastewater entering the pipes. To prevent that, it is imperative to efficiently monitor the urban underground infrastructure. The combination of sensors system and wireless underground communication system can be used to realize urban underground IoT applications, e.g., storm water and wastewater overflow monitoring systems. The aim of this article is to establish a feasibility of the use of wireless underground communications techniques, and wave propagation through the subsurface soil and asphalt layers, in an underground pavement system for storm water and sewer overflow monitoring application. …


Internet Of Things In Agricultural Innovation And Security, Abdul Salam Jan 2020

Internet Of Things In Agricultural Innovation And Security, Abdul Salam

Faculty Publications

The agricultural Internet of Things (Ag-IoT) paradigm has tremendous potential in transparent integration of underground soil sensing, farm machinery, and sensor-guided irrigation systems with the complex social network of growers, agronomists, crop consultants, and advisors. The aim of the IoT in agricultural innovation and security chapter is to present agricultural IoT research and paradigm to promote sustainable production of safe, healthy, and profitable crop and animal agricultural products. This chapter covers the IoT platform to test optimized management strategies, engage farmer and industry groups, and investigate new and traditional technology drivers that will enhance resilience of the farmers to the …


Internet Of Things For Water Sustainability, Abdul Salam Jan 2020

Internet Of Things For Water Sustainability, Abdul Salam

Faculty Publications

The water is a finite resource. The issue of sustainable withdrawal of freshwater is a vital concern being faced by the community. There is a strong connection between the energy, food, and water which is referred to as water-food-energy nexus. The agriculture industry and municipalities are struggling to meet the demand of water supply. This situation is particularly exacerbated in the developing countries. The projected increase in world population requires more fresh water resources. New technologies are being developed to reduce water usage in the field of agriculture (e.g., sensor guided autonomous irrigation management systems). Agricultural water withdrawal is also …


Internet Of Things In Water Management And Treatment, Abdul Salam Jan 2020

Internet Of Things In Water Management And Treatment, Abdul Salam

Faculty Publications

The goal of the water security IoT chapter is to present a comprehensive and integrated IoT based approach to environmental quality and monitoring by generating new knowledge and innovative approaches that focus on sustainable resource management. Mainly, this chapter focuses on IoT applications in wastewater and stormwater, and the human and environmental consequences of water contaminants and their treatment. The IoT applications using sensors for sewer and stormwater monitoring across networked landscapes, water quality assessment, treatment, and sustainable management are introduced. The studies of rate limitations in biophysical and geochemical processes that support the ecosystem services related to water quality …


Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, Abdul Salam, Syed Shah Apr 2019

Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, Abdul Salam, Syed Shah

Faculty Publications

The extra quantities of wastewater entering the pipes can cause backups that result in sanitary sewer overflows. Urban underground infrastructure monitoring is important for controlling the flow of extraneous water into the pipelines. By combining the wireless underground communications and sensor solutions, the urban underground IoT applications such as real time wastewater and storm water overflow monitoring can be developed. In this paper, the path loss analysis of wireless underground communications in urban underground IoT for wastewater monitoring has been presented. It has been shown that the communication range of up to 4 kilometers can be achieved from an underground …


Miss Lonesome: Old Boats Past Their Prime, Garth Woodruff Aug 2016

Miss Lonesome: Old Boats Past Their Prime, Garth Woodruff

Faculty Publications

No abstract provided.


Ecosystem Structure And Function In Two Branches Of An Eastern Minnesota, Usa, Trout Stream, Daniel J. Hornbach, Mark Hove, Maya Agata, Ellen Albright, Emily Cavazos, Clara Friedman, Katja Jay, Emily Johnson, Kari Johnson, Anna Staudenmaier Jul 2016

Ecosystem Structure And Function In Two Branches Of An Eastern Minnesota, Usa, Trout Stream, Daniel J. Hornbach, Mark Hove, Maya Agata, Ellen Albright, Emily Cavazos, Clara Friedman, Katja Jay, Emily Johnson, Kari Johnson, Anna Staudenmaier

Faculty Publications

No abstract provided.


Expansion Of The Manage Database With Forest And Drainage Studies, Daren R. Harmel, Laura E. Christianson, Matthew W. Mcbroom, Douglas R. Smith, Kori D. Higgs Jan 2016

Expansion Of The Manage Database With Forest And Drainage Studies, Daren R. Harmel, Laura E. Christianson, Matthew W. Mcbroom, Douglas R. Smith, Kori D. Higgs

Faculty Publications

The “Measured Annual Nutrient loads from AGricultural Environments” (MANAGE) database was published in 2006 to expand an early 1980s compilation of nutrient export (load) data from cultivated and pasture/range land at the field or farm scale. Then in 2008, MANAGE was updated with 15 additional studies, and nitrogen (N) and phosphorus (P) concentrations in runoff were added. Since then, MANAGE has undergone significant expansion adding N and P water quality along with relevant management and site characteristic data from: (1) 30 runoff studies from forested land uses, (2) 91 drainage water quality studies from drained land, and (3) 12 additional …


Water Soluble Cationic Porphyrin Sensor For Detection Of Hg2+, Pb2+, Cd2+, And Cu2+, Matibur Zamadar, Christopher Orr, Miranda Uherek Jan 2016

Water Soluble Cationic Porphyrin Sensor For Detection Of Hg2+, Pb2+, Cd2+, And Cu2+, Matibur Zamadar, Christopher Orr, Miranda Uherek

Faculty Publications

Here we report the sensing properties of the aqueous solution of meso-tetra(N-methyl-4-pyridyl)porphine tetrachloride (1) for simultaneous detection of toxic metal ions by using UV-vis spectroscopy. Cationic porphyrin 1 displayed different electronic absorptions in UV-vis region upon interacting with Hg2+, Pb2+, Cd2+, and Cu2+ ions in neutral water solution at room temperature. Quite interestingly, the porphyrin 1 showed that it can function as a single optical chemical sensor and/or metal ion receptor capable of detecting two or more toxic metal ions, particularly Hg2+, Pb2+, and Cd2+ ions coexisting in a water sample. Porphyrin 1 in an aqueous solution provides a unique …


Modeling Napl Dissolution From Pendular Rings In Idealized Porous Media, Junqi Huang, John A. Christ, Mark N. Goltz, Avery H. Demond Oct 2015

Modeling Napl Dissolution From Pendular Rings In Idealized Porous Media, Junqi Huang, John A. Christ, Mark N. Goltz, Avery H. Demond

Faculty Publications

The dissolution rate of nonaqueous phase liquid (NAPL) often governs the remediation time frame at subsurface hazardous waste sites. Most formulations for estimating this rate are empirical and assume that the NAPL is the nonwetting fluid. However, field evidence suggests that some waste sites might be organic wet. Thus, formulations that assume the NAPL is nonwetting may be inappropriate for estimating the rates of NAPL dissolution. An exact solution to the Young‐Laplace equation, assuming NAPL resides as pendular rings around the contact points of porous media idealized as spherical particles in a hexagonal close packing arrangement, is presented in this …


Semianalytical Solutions For Transport In Aquifer And Fractured Clay Matrix System, Junqi Huang, Mark N. Goltz Oct 2015

Semianalytical Solutions For Transport In Aquifer And Fractured Clay Matrix System, Junqi Huang, Mark N. Goltz

Faculty Publications

A three‐dimensional mathematical model that describes transport of contaminant in a horizontal aquifer with simultaneous diffusion into a fractured clay formation is proposed. A group of semianalytical solutions is derived based on specific initial and boundary conditions as well as various source functions. The analytical model solutions are evaluated by numerical Laplace inverse transformation and analytical Fourier inverse transformation. The model solutions can be used to study the fate and transport in a three‐dimensional spatial domain in which a nonaqueous phase liquid exists as a pool atop a fractured low‐permeability clay layer. The nonaqueous phase liquid gradually dissolves into the …