Physical Sciences and Mathematics Commons^™

Exploring A Fly Ash-Based Grouting Material For Toughening Through In Situ Polymerization Of Acrylamide, Zhang Yuehong, Wang Xiaodong, Wang Hai, Wu Boqiang, Ji Zhongkui, Zhu Shibin, Han Le, Feng Longfei

Coal Geology & Exploration

Efficiently controlling the water inflow (loss) of burnt rocks in the roof of coal mining faces requires grouting reinforcement materials with excellent compressive toughness. Silicate cement-based grouting materials, characterized by low costs, have been extensively applied to grouting reinforcement in coal mines. However, their hardened grout is susceptible to deformation, exhibiting poor toughness. By employing the in-situ polymerization of acrylamide (AM) for toughening, this study investigated the effects of AM, cross-linking agent, initiator, and water-cement ratio on the setting time, swelling capacity, compressive strength, and toughness index of the fly ash-based grouting materials. Furthermore, the microstructures of the hardened grout …

Study On Optimum Cultivation Techniques Of Alfalfa On Songnen Plain, Fengjiu Chai, Zedong Liu

IGC Proceedings (1997-2023)

No abstract provided.

Establishment And Optimization Of The Issr‐Pcr Reaction System In Stipa Krylovii, Xiaoqing Sui, Kun Wang, Shuhua Zheng, Li Lin

IGC Proceedings (1997-2023)

No abstract provided.

Investigation And Simutation On The Model And Prevention Technology Of Water Inrush From Roof Bed Separation, Zhang Wenquan, Wang Zaiyong, Wu Xintao, Shao Jianli, Lei Yu, Wu Xunan

Coal Geology & Exploration

In order to prevent water inrush from roof separation, a partial backfill scheme is proposed for simulation study. First of all, based on the existing data, many kinds of separation water inrush accidents occurred in China were summarized and analyzed, and the disaster model of separation water accumulation was studied deeply. Then, taking the separation water accident of 1307 working face in the first mining area of a mine in Shaanxi Province as an example, the hydrogeological conditions and the relationship between upper aquifer and separation water inrush were analyzed, and the development characteristics of roof separation space of working …

Sustainability And Optimization Of Rangeland Uses: Issues Of Perspective And Scale, T. L. Thurow

IGC Proceedings (1997-2023)

No abstract provided.

Calibration Optimization Of A Stream Temperature Model Applied To The Nooksack River, Ian Edgar

Scholars Week

The River Basin Model (RBM) is used to assess how stream temperatures will change in the Nooksack River due to warming climates by tracking heat exchanges along stream segments. Before modeling forecasted climate scenarios, I first calibrated the model to observed historical stream temperatures. The calibration of the RBM to a stream network involves the adjustment of eleven different variables until the simulated temperatures match observed historical stream temperatures. Because the manual process of calibrating the model is extremely time consuming, I developed a Python script to converge on the optimal variables required for the RBM calibration. The script adjusts …

Optimization Of Some Parameters On Desulfurization Process Of Muğla Yatağan Bağyaka Lignite By Ultrasonic Waves, İlkay Ünal Sansar

Bulletin of the Mineral Research and Exploration

In this study, the desulfurization process developed using ultrasonic waves for Muğla Yatağan Bağyaka lignite had the optimum conditions for parameters affecting the ash and sulfur removal potentials determined with the Surface Response Method and a model created. The process parameters to obtain optimum desulfurization and ash removal were chosen as the ultrasonic treatment time, solid content, concentration of chemical reactive (H₂O₂) and reactive volume, and the optimum values were determined. Using this data with the aid of the Design Export 7.0 program, the regression model was found as a second degree polynomial equation. The coefficients …

Designing A Protected Area To Safeguard Imperiled Species From Urbanization, Stephanie S. Romanach, Brad Stith, Fred A. Johnson

United States Geological Survey: Staff Publications

Reserve design is a process that can address ecological, social, and political factors to identify parcels of land needed to sustain wildlife populations and other natural resources. Acquisition of parcels for a large terrestrial reserve is difficult because it typically occurs over a long timeframe and thus invokes consideration of future conditions such as climate and urbanization changes. In central Florida, the U.S. government has authorized a new protected area, the Everglades Headwaters National Wildlife Refuge. The new refuge will host important threatened and endangered species and habitats, and will be located to allow for species adaptation from climate change …

Optimizing Barrier Removal To Restore Connectivity In Utah’S Weber Basin, Maggi Kraft

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

River barriers, such as dams, culverts and diversions are important for water conveyance, but disrupt river ecosystems and hydrologic processes. River barrier removal is increasingly used to restore and improve river habitat and connectivity. Most past barrier removal projects prioritized individual barriers using score-and-rank techniques, neglecting the spatial structure and cumulative change from multiple barrier removals. Similarly, most water demand models satisfy human water uses or, only prioritize aquatic habitat, failing to include both human and environmental water use benefits. In this study, a dual objective optimization model identified in-stream barriers that impede quality-weighted aquatic habitat connectivity for Bonneville cutthroat …

Pso Algorithm For An Optimal Power Controller In A Microgrid, Waleed Al-Saedi, Stefan Lachowicz, Daryoush Habibi, Octavian Bass

Research outputs 2014 to 2021

This paper presents the Particle Swarm Optimization (PSO) algorithm to improve the quality of the power supply in a microgrid. This algorithm is proposed for a real-time selftuning method that used in a power controller for an inverter based Distributed Generation (DG) unit. In such system, the voltage and frequency are the main control objectives, particularly when the microgrid is islanded or during load change. In this work, the PSO algorithm is implemented to find the optimal controller parameters to satisfy the control objectives. The results show high performance of the applied PSO algorithm of regulating the microgrid voltage and …

Improved 2d And 3d Resistivity Surveys Using Buried Electrodes And Optimized Arrays: The Multi-Electrode Resistivity Implant Technique (Merit), Henok Gidey Kiflu

USF Tampa Graduate Theses and Dissertations

This thesis presents a novel resistivity method called Multi-Electrode resistivity technique (MERIT) that is used for high resolution imaging of complex geologic features at depth and near the edges of survey lines. The MERIT electrodes are especially shaped and designed to be self-driven using a robust-direct push technique. Measurements are taken using optimized arrays that are generated using a modified version of the “Compare-R” optimization algorithm. This work focused on both two-dimensional (MERIT2D) and three-dimensional (MERIT3D) applications of the buried array and show the relevance of the additional information gained by the addition of deep electrodes especially in sites with …

Stabilized Least Squares Migration, Graham Ganssle

University of New Orleans Theses and Dissertations

Before raw seismic data records are interpretable by geologists, geophysicists must process these data using a technique called migration. Migration spatially repositions the acoustic energy in a seismic record to its correct location in the subsurface. Traditional migration techniques used a transpose approximation to a true acoustic propagation operator. Conventional least squares migration uses a true inverse operator, but is limited in functionality by the large size of modern seismic datasets. This research uses a new technique, called stabilized least squares migration, to correctly migrate seismic data records using a true inverse operator. Contrary to conventional least squares migration, this …

Improving Processing By Adaption To Conditional Geostatistical Simulation Of Block Compositions, R. Tolosana-Delgado, Ute A. Mueller, K. G. Van Den Boogaart, C. Ward, J. Gutzmer

Research outputs 2014 to 2021

Exploitation of an ore deposit can be optimized by adapting the beneficiation processes to the properties of individual ore blocks. This can involve switching in and out certain treatment steps, or setting their controlling parameters. Optimizing this set of decisions requires the full conditional distribution of all relevant physical parameters and chemical attributes of the feed, including concentration of value elements and abundance of penalty elements. As a first step towards adaptive processing, the mapping of adaptive decisions is explored based on the composition, in value and penalty elements, of the selective mining units. Conditional distributions at block support are …

Optimization Schemes For The Inversion Of Bouguer Gravity Anomalies, Azucena Zamora

Open Access Theses & Dissertations

Data sets obtained from measurable physical properties of the Earth structure have helped advance the understanding of its tectonic and structural processes and constitute key elements for resource prospecting. 2-Dimensional (2-D) and 3-D models obtained from the inversion of geophysical data sets are widely used to represent the structural composition of the Earth based on physical properties such as density, seismic wave velocities, magnetic susceptibility, conductivity, and resistivity. The inversion of each one of these data sets provides structural models whose consistency depends on the data collection process, methodology, and overall assumptions made in their individual mathematical processes. Although sampling …

Economic Growth Assumptions In Climate And Energy Policy, Nir Y. Krakauer

Publications and Research

The assumption that the economic growth seen in recent decades will continue has dominated the discussion of future greenhouse gas emissions and the mitigation of and adaptation to climate change. Given that long-term economic growth is uncertain, the impacts of a wide range of growth trajectories should be considered. In particular, slower economic growth would imply that future generations will be relatively less able to invest in emissions controls or adapt to the detrimental impacts of climate change. Taking into consideration the possibility of economic slowdown therefore heightens the urgency of reducing greenhouse gas emissions now by moving to renewable …

A Numerical Testbed For Remote Sensing Of Aerosols, And Its Demonstration For Evaluating Retrieval Synergy From A Geostationary Satellite Constellation Of Geo-Cape And Goes-R, Jun Wang, Xiaoguang Xu, Shouguo Ding, Jing Zeng, Robert Spurr, Xiong Liu, Kelly Chance, Michael I. Mishchenko

Department of Earth and Atmospheric Sciences: Faculty Publications

We present a numerical testbed for remote sensing of aerosols, together with a demonstration for evaluating retrieval synergy from a geostationary satellite constellation. The testbed combines inverse (optimal-estimation) software with a forward model containing linearized code for computing particle scattering (for both spherical and non-spherical particles). a kernel-based (land and ocean) surface bi-directional reflectance facility, and a linearized radiative transfer model for polarized radiance. Calculation of gas absorption spectra uses the HITRAN (HIgh-resolution TRANsmission molecular absorption) database of spectroscopic line parameters and other trace species cross-sections. The outputs of the testbed include not only the Stokes 4-vector elements and their …

Water Demand And Allocation In The Mara River Basin, Kenya/Tanzania In The Face Of Land Use Dynamics And Climate Variability, Shimelis B. Dessu

FIU Electronic Theses and Dissertations

The Mara River Basin (MRB) is endowed with pristine biodiversity, socio-cultural heritage and natural resources. The purpose of my study is to develop and apply an integrated water resource allocation framework for the MRB based on the hydrological processes, water demand and economic factors. The basin was partitioned into twelve sub-basins and the rainfall runoff processes was modeled using the Soil and Water Assessment Tool (SWAT) after satisfactory Nash-Sutcliff efficiency of 0.68 for calibration and 0.43 for validation at Mara Mines station. The impact and uncertainty of climate change on the hydrology of the MRB was assessed using SWAT and …

Modeling Direct Runoff Hydrographs With The Surge Function, Denis Voytenko

USF Tampa Graduate Theses and Dissertations

A surge function is a mathematical function of the form f(x)=ax^pe^-bx. We simplify the surge function by holding p constant at 1 and investigate the simplified form as a potential model to represent the full peak of a stream discharge hydrograph. The previously studied Weibull and gamma distributions are included for comparison. We develop an analysis algorithm which produces the best-fit parameters for every peak for each model function, and we process the data with a MATLAB script that uses spectral analysis to filter year-long, 15-minute, stream-discharge data sets. The filtering is necessary to locate the …

On Constrained Optimization Schemes For Joint Inversion Of Geophysical Datasets, Uram Anibal Sosa Aguirre

Open Access Theses & Dissertations

In the area of geological sciences, there exist several experimental techniques used to advance in the understanding of the Earth. We implement a joint inversion least-squares (LSQ) algorithm to characterize one dimensional Earth's structure by using seismic shear wave velocities as a model parameter. We use two geophysical datasets sensitive to shear velocities, namely Receiver Function and Surface Wave dispersion velocity observations, with a choice of an optimization method: Truncated Singular Value Decomposition (TSVD) or Primal-Dual Interior-Point (PDIP). The TSVD and the PDIP methods solve a regularized unconstrained and a constrained minimization problem, respectively. Both techniques include bounds into the …

Cleaning Of Rivers Through The Application Of Advanced Technologies, Praveen Jha Dr

Praveen Jha Dr

Despite immense drain on our scarce resources, rivers remain polluted. Waste disposal into rivers on top of meager to absent infrastructural facilities, including treatment facilities, are the most important drivers of pollution. Unscientific development paradigm devoid of adequate environmental safeguards and failure of forestry sector to cope up with the challenge has led to the deteriorated condition of green cover and water. Several state-of-art geo-spatial programs developed by the author would be applied for generating optimum state-of-art plan. Three state-of-art geo-spatial programs - Multi-Algorithm Automation Program (MAAP), Data Automatic Modification Program (DAMP) and Multi-Stage Simulation Program (MUSSIP) - developed primarily …

Optimal Irrigation Management For Sloping, Blocked-End Borders, Jorge Jose Escurra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A robust mathematical model of one-dimensional flow for sloping, blocked-end border irrigation was developed using the four-point implicit method to solve the Saint-Venant equations, the volume-balance solution method, and the implementation of new algorithms to avoid numerical instability and solution divergence. The model has the capability of successfully simulating all surface irrigation phases in blocked-end borders for a range of inflow rates (0.01 - 0.05 m³/s per m), longitudinal slopes (up to 1.00%), and border lengths (100 - 500 m).

To achieve numerical stability over the specified parameter ranges, the model was divided into three parts: (1) advance-phase …

Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis

Technical Reports

Presented are alternative techniques for including conservative solute transport within computer models for optimizing groundwater extraction rates. Unsteady two-dimensional flow and dispersed conservative solute transport are assumed. Comparisons are made of the practicality of including modified forms of implicit and explicit finite difference solute transport equations within optimization models. These equations can be calibrated and subsequently used within a MODCON procedure. The MODCON modelling procedure consists of an integrated series of five optimization or simulation modules. The procedure is applicable for either an entire aquifer system or for a subsystem of a larger system. The first module, A, computes physically …

An Application Of Discrete Optimization For Developing Economically Efficient Multiple-Use Projects, United States Department Of Agriculture, Forest Service

Forestry

A discrete version of the continuous joint production model in economic theory is presented for use in designing multiple-use projects and identifying efficient management prescriptions for forest planning. Data requirements are less demanding than the continuous theoretical model, yet some of the more important features are maintained. Models can be formulated graphically or as mixed-integer programming problems that are easily solved via computerized routines.