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Full-Text Articles in Physical Sciences and Mathematics

Wave Attenuation Through Submerged Oyster Aquaculture Cages, Liam T. Hanley Aug 2023

Wave Attenuation Through Submerged Oyster Aquaculture Cages, Liam T. Hanley

Electronic Theses and Dissertations

Coastal erosion presents a growing issue to shorelines around the world and is especially harmful to Maine, a region where sea-level rise is higher than the global average. Green and hybrid coastal defense strategies are being implemented around the country to provide sustainable, habitat-friendly solutions to erosion control. Maine is a hotspot for commercial aquaculture, with an estimated $13.6 million economic impact. This study looks to bridge the gap between Maine aquaculture and the living shorelines initiative, by determining the wave attenuating properties of submerged oyster cages. The project will be able to inform local oyster farmers, resource planners, and …


Anthropogenic Effects On Tidal Distortion In A Tidal River, Matthew D. Fischer Dec 2022

Anthropogenic Effects On Tidal Distortion In A Tidal River, Matthew D. Fischer

Electronic Theses and Dissertations

Tidal rivers are landward portions of estuarine systems constituting the union between coastal, tidally controlled settings and rivers, where fluvial processes dominate. In these reaches, river discharge (mean flow) and tides are the two most important mechanisms in controlling geophysical flows. The processes governing water levels and current amplitudes in tidal rivers are highly nonlinear and modulated by external forcings- thus requiring sophisticated techniques for accurate prediction and forecasting. Physical oceanographers and estuarine physicists tend to limit their study area to the maximum extent of the horizontal tide (salinity intrusion), not the most landward point influenced by tidal water levels. …


Comparison Of Land Use And Flowslide Incidence In Palu Valley Following The 2018 Mw 7.5 Palu-Donggala Earthquake, Peta C. Fifield Aug 2021

Comparison Of Land Use And Flowslide Incidence In Palu Valley Following The 2018 Mw 7.5 Palu-Donggala Earthquake, Peta C. Fifield

Electronic Theses and Dissertations

The September 28 Mw 7.5 Palu-Donggala earthquake in Indonesia was the deadliest natural disaster in 2018. Five flowslides on the eastern side of Palu Valley, which were attributed to the substantial majority of deaths and economic losses in the region, occurred due to liquefaction of naturally dry alluvial deposits in gently sloping ground (2 to 6%). The requisite conditions for soil liquefaction are the presence of loose granular sediments and full saturation. Instigation of these catastrophic ground failures were linked to artificial saturation by an unlined agricultural irrigation canal. From a civil engineering perspective, the Palu ground failures on the …


Hydrodynamic Impacts Of Expanding Aquaculture, Zhilong Liu May 2021

Hydrodynamic Impacts Of Expanding Aquaculture, Zhilong Liu

Electronic Theses and Dissertations

Climate change may potentially change aquatic systems and bring certain risks for aquaculture development. Understanding interactions between aquaculture and the environment helps to ensure aquaculture expansion is sustainable in the future. It is critical to determine how farms influence tidal flow patterns, turbulence, mixing and material transport in estuaries. This research aims to determine the flow response of an oyster farm, predict how expanding farms and farm placement will alter estuarine dynamics, and understand how the design of a farm influences material transport.

The hydrodynamic response of a floating oyster aquaculture farm in a low inflow estuary (the Damariscotta River …


Coastal Windstorms Create Unsteady, Unpredictable Storm Surges In A Fluvial Maine Estuary, Preston Spicer, Pascal Matte, Kimberly Huguenard, Laura N. Rickard Apr 2021

Coastal Windstorms Create Unsteady, Unpredictable Storm Surges In A Fluvial Maine Estuary, Preston Spicer, Pascal Matte, Kimberly Huguenard, Laura N. Rickard

Civil Engineering Faculty Scholarship

Storm surges create coastal flooding that can be damaging to life and property. In estuaries with significant river influence (fluvial), it is possible for tides, storm surge, and river discharge to interact and enhance surges relative to the immediate coast. These tide-surge-river interactions were previously identified in a fluvial Maine estuary as higher frequency (>four cycles per day) oscillations to storm surge which were proposed to be incited by enhanced friction and resonance during certain windstorm events (Spicer et al. 2019). The relative contributions to tide-surge-river interaction from atmospheric forcing variables (wind, barometric pressure, and externally generated surge) remains …


Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina Nov 2019

Modeling Response Of Water Quality To Land-Use And Climate Change In Lake Auburn, Me, Nicholas Messina

Electronic Theses and Dissertations

Lake Auburn, Maine, USA, is a historically unproductive lake that has experienced multiple algal blooms since 2011. The lake is the water supply source for a population of ~60,000. We modeled past temperature, and concentrations of dissolved oxygen (DO) and phosphorus (P) in Lake Auburn by considering the watershed and internal contributions of P as well as atmospheric factors, and predicted the change in lake water quality in response to future climate and land-use changes. A stream hydrology and P-loading model (SimplyP) was used to generate input from two major tributaries into a lake model (MyLake) to simulate physical mixing, …


Tide And Storm Surge Dynamics In Estuaries Of Variable Morphology, Preston Spicer May 2019

Tide And Storm Surge Dynamics In Estuaries Of Variable Morphology, Preston Spicer

Electronic Theses and Dissertations

Storm surges are the most destructive component of coastal storms, and climate change is predicted to enhance the frequency of intense storm events in the future. Currently, most storm surge forecasting assumes linear surges and the extent to which this assumption leads to model inaccuracies is currently unknown. The goals of this research are to characterize storm surge in estuaries and determine the contribution of nonlinear tide-surge interaction to total inland surges. A citizen science experiment was conducted in four estuaries in Maine. Results show the estuary shape influences surges through convergence, friction and man-made constrictions. These mechanisms modified total …


Perspectives On Water Resources Risk, Policy, And Stewardship, Anne Marie Lausier May 2019

Perspectives On Water Resources Risk, Policy, And Stewardship, Anne Marie Lausier

Electronic Theses and Dissertations

Water management approaches have historically optimized water for human use and placed lower emphasis on the relationship between ecosystems and humans. Despite efforts to balance human and ecosystem needs, existing management approaches tend to prioritize some needs, knowledges, and values over others. Natural and anthropogenic changes pose challenges to water governance institutions due to policy inflexibility, and may lead to ecosystem degradation, water stress, and conflict among water users. This work seeks to redress these shortcomings through three scholarly contributions. First, a conceptual framework for Water Resources Stewardship is developed in support of equitable and adaptive solutions under changing conditions. …


Controls On Phosphorus Export From An Agricultural Watershed: Amsden Brook, Fort Fairfield, Maine Usa., Gregory J. Mcdonald Dec 2018

Controls On Phosphorus Export From An Agricultural Watershed: Amsden Brook, Fort Fairfield, Maine Usa., Gregory J. Mcdonald

Electronic Theses and Dissertations

This study explores the sources and mechanisms of phosphorus (P) mobilization during base flow within the Amsden Brook watershed, Fort Fairfield, Maine, USA. Amsden Brook is an agriculturally dominated watershed drained by a spring-fed and perennial first- to second-order stream. We characterized the P concentrations within the watershed to investigate connections between soils, stream sediment, surface water, and groundwater. Waters were monitored monthly during the 2017 snow-free period for temperature, pH, dissolved oxygen, conductivity, soluble reactive P (SRP), total P, strong acid anions, strong base cations, dissolved organic carbon (DOC), Al, Fe, and Mn. Phosphorus speciation within soils and sediment …


Three-Dimensional Bedrock Channel Evolution With Smoothed Particle Hydrodynamics, Nick Richmond Dec 2018

Three-Dimensional Bedrock Channel Evolution With Smoothed Particle Hydrodynamics, Nick Richmond

Electronic Theses and Dissertations

Bedrock channels are responsible for balancing and communicating tectonic and climatic signals across landscapes, but it is difficult and dangerous to observe and measure the flows responsible for removing weakly-attached blocks of bedrock from the channel boundary. Consequently, quantitative descriptions of the dynamics of bedrock removal are scarce. Detailed numerical simulation of violent flows in three dimensions has been historically challenging due to technological limitations, but advances in computational fluid dynamics aided by high-performance computing have made it practical to generate approximate solutions to the governing equations of fluid dynamics. From these numerical solutions we gain detailed knowledge of the …


Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner Dec 2017

Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner

Electronic Theses and Dissertations

Vernal pools are small seasonal wetlands that are a common landscape feature that contribute to biodiversity in northeastern North American forests. However, even basic information about their biogeochemical functions, such as carbon cycling, is limited. Dissolved gas concentrations (CH4, CO2) and other water chemistry parameters were monitored weekly at the bottom and surface of four vernal pools in central and eastern Maine, USA, from April to August 2016. The vernal pools were supersaturated with respect to CH4 and CO2 at all sampling dates and locations. Concentrations of dissolved CH4 and CO2 ranged …


Transformation Of Nonlinear Waves In The Presence Of Wind, Current, And Vegetation, Haifei Chen Dec 2017

Transformation Of Nonlinear Waves In The Presence Of Wind, Current, And Vegetation, Haifei Chen

Electronic Theses and Dissertations

Accurate prediction of extreme wave events is crucial for the safe maritime activities and offshore operations. Improved knowledge of wave dissipation mechanisms due to breaking and vegetation leads to accurate wave forecast, protecting life and property along the coast. The scope of the thesis is to examine the wave transformations in the presence of wind, current, and vegetation, using a two-phase flow solver based on the open-source platform OpenFOAM. The Reynolds-Averaged Navier-Stokes (RANS) equations are coupled with a Volume of Fluid (VOF) surface capturing scheme and a turbulence closure model. This RANS-VOF model is adapted to develop a numerical wind-wave-current …


Window Inserts And The People Adopting Them: Building Sustainable Communities In Maine, Daniel Sean Mistro Aug 2017

Window Inserts And The People Adopting Them: Building Sustainable Communities In Maine, Daniel Sean Mistro

Electronic Theses and Dissertations

Residents of Maine face a large monetary expense to heat their homes in the winter. In Maine it takes 540 gallons of heating oil each year to heat a typical home [1]. Interior window inserts may be a practical solution to improve comfort, save money, and consume less environmentally harmful fossil fuels during cold winter months. The window inserts discussed in this paper are custom measured to fit into a window and consist of a wooden frame that is wrapped in two layers of polyolefin film and weather stripped for a snug fit. Commercial inserts cost $20-$36/square foot, or approximately …


Microstructural Analysis Of Thermoelastic Response, Nonlinear Creep, And Pervasive Cracking In Heterogeneous Materials, Alden C. Cook Dec 2016

Microstructural Analysis Of Thermoelastic Response, Nonlinear Creep, And Pervasive Cracking In Heterogeneous Materials, Alden C. Cook

Electronic Theses and Dissertations

This dissertation is concerned with the development of robust numerical solution procedures for the generalized micromechanical analysis of linear and nonlinear constitutive behavior in heterogeneous materials. Although the methods developed are applicable in many engineering, geological, and materials science fields, three main areas are explored in this work. First, a numerical methodology is presented for the thermomechanical analysis of heterogeneous materials with a special focus on real polycrystalline microstructures obtained using electron backscatter diffraction techniques. Asymptotic expansion homogenization and finite element analysis are employed for micromechanical analysis of polycrystalline materials. Effective thermoelastic properties of polycrystalline materials are determined and compared …


Exfoliated Graphite Nanoplatelet-Filled Impact Modified Polypropylene Nanocomposites, Alex Duguay May 2011

Exfoliated Graphite Nanoplatelet-Filled Impact Modified Polypropylene Nanocomposites, Alex Duguay

Electronic Theses and Dissertations

Exfoliated graphite nanoplatelets (xGnP)-filled polymer composites have demonstrated superior electrical, mechanical, physical and thermal properties and are becoming a major focus for both academic and industrial research and development (R&D) activities. The main objective of this study was to characterize the influence of xGnP particle diameter, filler loading and the addition of coupling agents on the mechanical, rheological and thermal properties of xGnP-filled impact modified polypropylene (IMPP) composites. IMPP is currently being used at the AEWC Advanced Structures and Composites Center in polymer impregnated (pre-preg) fiber reinforced polymer (FRP) tapes consisting of an IMPP matrix polymer and E-glass continuous fibers. …


Development In The Gulf Of Maine: Avoiding Geohazards And Embracing Opportunities, Laura L. Brothers, Joseph T. Kelley, Melissa Landon Maynard, Daniel F. Belknap, Stephen M. Dickson Jan 2010

Development In The Gulf Of Maine: Avoiding Geohazards And Embracing Opportunities, Laura L. Brothers, Joseph T. Kelley, Melissa Landon Maynard, Daniel F. Belknap, Stephen M. Dickson

Maine Policy Review

Mapping for marine-spatial planning is crucial if Maine is to safely develop its offshore resources, espe­cially wind and tidal energy. The authors focus on shallow natural gas (methane) deposits, an important and widespread geohazard in Maine’s seafloor. They describe the origin, occur­rence, and identification of natural gas in Maine’s seafloor; explain the hazards associated with these deposits and how to map them; and discuss what Maine can learn from European nations that have already developed their offshore wind resources. Because the U.S. gives states a central role in coastal management, Maine has the chance to be proactive in delineating coastal …


Nirt: Developing A Nanoscale Sensing Device For Measuring The Supply Of Iron To Phytoplankton In Marine Systems, Mark L. Wells, Karen Orcutt, D. Whitney King, Carl Tripp Dec 2007

Nirt: Developing A Nanoscale Sensing Device For Measuring The Supply Of Iron To Phytoplankton In Marine Systems, Mark L. Wells, Karen Orcutt, D. Whitney King, Carl Tripp

University of Maine Office of Research Administration: Grant Reports

There is increasing evidence that Fe has a singularly unique role in marine ecosystems, both regulating total phytoplankton production in high nitrate, low chlorophyll regions of the world, and influencing the predominant composition of the phytoplankton assemblages found in others. It is remarkable then that there is no agreement about how to define biologically available Fe, in contrast to the macronutrients nitrogen, phosphorous or silicon. Current attempts to attain predictive insights to how ocean ecosystems will influence the magnitude of climate change are blocked in large part by this question, along with an extreme shortage of data on Fe distributions …


The Maine Shore And The Army Corps: A Tale Of Two Harbors, Wells And Saco, Maine, Joseph Kelley, Walter Anderson Jan 2000

The Maine Shore And The Army Corps: A Tale Of Two Harbors, Wells And Saco, Maine, Joseph Kelley, Walter Anderson

Maine Policy Review

By discussing the problems of beach erosion and sand movement at Wells and Saco, Maine, Joseph Kelley and Walter Anderson demonstrate how single-minded, engineering approaches to complex, interdisciplinary coastal issues can create bigger problems than previously existed. As Kelley and Anderson explain, at both Wells and Camp Ellis, the Army Corps of Engineers was brought in to construct a harbor at no local cost to the community. This was accomplished by constructing jetties, and the result has been a persistent and serious problem of beach erosion. Over the years, the Army Corps has offered further technical solutions that have served …


Dickey-Lincoln School Lakes Project At Dickey, Maine : Final Environmental Impact Statement, New England Division, United States Army Engineer Division Jan 1981

Dickey-Lincoln School Lakes Project At Dickey, Maine : Final Environmental Impact Statement, New England Division, United States Army Engineer Division

Dickey-Lincoln School Lakes Project

The Final Impact Statement is supported by all appendices from all drafts as well as supplementary information provided in Supplements to those Appendices. It comprises three volumes. Volume I is the statement volume. Volume II consists of two parts. Part I contains the comment and response portion of Section 9 for the 1977 Draft EIS. Part II contains comments and responses on the 1978 Revised Draft EIS, in addition to reproductions of the original comment letters received on the Draft Fish and Wildlife Mitigation Report and responses to these comments. Volume III, Part I contains reproductions of the original comment …


Dickey-Lincoln School Lakes Project At Dickey, Maine : Final Environmental Statement, New England Division, United States Army Engineer Division Jan 1981

Dickey-Lincoln School Lakes Project At Dickey, Maine : Final Environmental Statement, New England Division, United States Army Engineer Division

Dickey-Lincoln School Lakes Project

This document contains those comments and responses on the Revised Draft Environmental Impact Statement. It is a continuation of Volume II published by the Corps in 1978. In addition, it contains reproductions of those letters of comment received on the March 1980 Draft Fish and Wildlife Mitigation Plan, and the responses to these comments.


Dickey-Lincoln School Lakes, Maine, Hydro-Power Decision, October 27, 1978, James B. Longley Jan 1978

Dickey-Lincoln School Lakes, Maine, Hydro-Power Decision, October 27, 1978, James B. Longley

Dickey-Lincoln School Lakes Project

The Dickey-Lincoln School Project would consist of two earthfill structures designed to produce peaking and modest intermediate load power from the St. John River The larger of the two dams, the Dickey Dam, would be located immediately above the confluence of the Allagash and St. John Rivers. The Lincoln School Dam would also be located on the Upper St. John River, eleven miles downstream from the Dickey Dam. The Dickey Dam would have a total length of 10,600 feet and a maximum height of 335 feet. The Lincoln School Dam is considerably smaller and would be 1,600 feet long and …


Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix B: Alternative Power Transmission Corridors, United States Department Of Energy, United States Department Of The Interior Jan 1978

Dickey-Lincoln School Lakes Project Transmission Studies Environmental Impact Statement: Appendix B: Alternative Power Transmission Corridors, United States Department Of Energy, United States Department Of The Interior

Dickey-Lincoln School Lakes Project

This report identifies alternative corridors of land within which transmission lines could be routed and details various impacts on the environment which would be associated with introduction of transmission facilities. Many alternative corridor locations were identified (see Figure 1-1). Identification of these alternative transmission corridors was a complex process, since the number of potential corridors capable of connecting the various substations was myriad; the 'least desirable' potential corridors, i.e., those where transmission facilities might have entailed severest impacts on the environment, had to be eliminated from consideration before alternative corridors could be delineated. Identified alternative corridor locations were subsequently evaluated …


Dickey-Lincoln School Lakes Project At Dickey, Maine : Draft Environmental Impact Statement, New England Division, United States Army Engineer Division Jan 1977

Dickey-Lincoln School Lakes Project At Dickey, Maine : Draft Environmental Impact Statement, New England Division, United States Army Engineer Division

Dickey-Lincoln School Lakes Project

This draft EIS address the impacts of the dams and appurtenant structures. The marketing and transmission of power from Federal projects are the statutory responsibility of the Department of the Interior. Accordingly, they are conducting transmission line studies in the preparation of a draft EIS. The draft EIS for transmission line and marketing is scheduled to be submitted to the Council on Environmental Quality in February 1978. Both drafts will be combined and submitted as a Final Environmental Impact Statement in August 1978.


Dickey-Lincoln School Lakes Project Environmental Impact Statement: Appendix H: Noise Impact Assessment, Stone & Webster Engineering Corporation, New England Division, United States Army Engineer Division Jan 1977

Dickey-Lincoln School Lakes Project Environmental Impact Statement: Appendix H: Noise Impact Assessment, Stone & Webster Engineering Corporation, New England Division, United States Army Engineer Division

Dickey-Lincoln School Lakes Project

The overall project area can be described as a very quiet natural area remote from any major industrial activity, but subject to high traffic noise levels along the main road. Noise sensitive areas consist of low density residential areas in the villages and widely spaced residences along the main road. The estimated yearly average Ldn for all noise sensitive areas 1s 60 dB due to the close proximity of traffic to all residences. The yearly average Ldn decreases to 40 dB at 600 ft from the main road, and to 30 dB 1n the timberland areas.


Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 4a: General Design (Revised), New England Division, United States Corps Of Engineers Jan 1977

Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 4a: General Design (Revised), New England Division, United States Corps Of Engineers

Dickey-Lincoln School Lakes Project

This design memorandum presents for review the revised general plan and data for the Dickey-Lincoln School Lakes project, Maine, U.S.A. and Quebec, Canada to provide the basis for preparation of detailed design memoranda, plans and specifications. This document presents revisions to the basic project plan and related data included in the 1967 General Design Memorandum reflecting current water resource requirements. This memorandum serves as a functional design document and 1s presented 1n Phase II level of detail. However, 1n view of the long period of Inactivity, Phase I features have also been incorporated for continuity of project information.


Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 2: Hydrology And Hydraulic Analysis: Section 3 - Dickey Dam-Spillway Design Flood, Army. Corps Of Engineers. New England Division Jan 1975

Dickey-Lincoln School Lakes, Maine, U.S.A. And Quebec, Canada: Design Memorandum No. 2: Hydrology And Hydraulic Analysis: Section 3 - Dickey Dam-Spillway Design Flood, Army. Corps Of Engineers. New England Division

Dickey-Lincoln School Lakes Project

This report, Section III, is the third of five sections comprising Design Memorandum No. 2. This section, on the development of the spillway design flood (SDF) for the Dickey project, describes the hydrologic criteria used and analysis performed in determining the SDF and the results of routing the flood through the reservoir in order to establish surcharge-length relations for the spillway at Dickey Dam. Also included is a discussion of freeboard requirements, frequency of filling data, an update of climatologic data and daily discharge records of the Saint John and Allagash Rivers.