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Articles 421 - 450 of 1203

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot Jul 2022

Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot

LSU Master's Theses

Coastal wetlands provide an abundance of ecosystem services that benefit society, such as essential habitat for commercial species, storm protection, nutrient cycling, and carbon storage. Louisiana faces rapid rates of relative sea level rise (natural subsidence and eustatic sea levels) that threaten wetland survival, which are amplified by a reduction of riverine sediment input. An important determining factor of marsh survival is the formation of wetland platform elevation, known as vertical accretion, which is determined by several processes including sediment deposition & erosion, below ground biomass (BGB) productivity, decomposition of organic matter, shallow & deep subsidence, and soil compaction. Feldspar …

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Tracing Geochemical Sources And Health Risk Assessment Of Uranium In Groundwater Of Arid Zone Of India, P. Pandit, Atul Saini, Sabarathinam Chidambaram, Vinod Kumar, Banjarani Panda, A. L. Ramanathan, Netrananda Sahu, A. K. Singh, Rohit Mehra Jun 2022

Tracing Geochemical Sources And Health Risk Assessment Of Uranium In Groundwater Of Arid Zone Of India, P. Pandit, Atul Saini, Sabarathinam Chidambaram, Vinod Kumar, Banjarani Panda, A. L. Ramanathan, Netrananda Sahu, A. K. Singh, Rohit Mehra

Nebraska Water Center: Faculty Publications

Water quality degradation and metal contamination in groundwater are serious concerns in an arid region with scanty water resources. This study aimed at evaluating the source of uranium (U) and potential health risk assessment in groundwater of the arid region of western Rajasthan and northern Gujarat. The probable source of vanadium (V) and fluorine (F) was also identified. U and trace metal concentration, along with physicochemical characteristics were determined for 265 groundwater samples collected from groundwater of duricrusts and palaeochannels of western Rajasthan and northern Gujarat. The U concentration ranged between 0.6 and 260 μg L−1 with a mean …

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Developing A Miniature Smart Boat For Marine Research, Michael Isaac Eirinberg Jun 2022

Developing A Miniature Smart Boat For Marine Research, Michael Isaac Eirinberg

Computer Engineering

This project examines the development of a smart boat which could serve as a possible marine research apparatus. The smart boat consists of a miniature vessel containing a low-cost microcontroller to live stream a camera feed, GPS telemetry, and compass data through its own WiFi access point. The smart boat also has the potential for autonomous navigation. My project captivated the interest of several members of California Polytechnic State University, San Luis Obispo’s (Cal Poly SLO) Marine Science Department faculty, who proposed a variety of fascinating and valuable smart boat applications.

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In Situ Observations Of Fish Attraction To Light-Emitting Diodes On An Undersea Observation Deck, Makoto Tomiyasu, Yoko Tanouchi, Yasuzumi Fujimori, Minato Kaji, Takuma Hayashi, Naoto Matsubara, Hiroki Yasuma, Susumu Shimizu, Seiji Katakura May 2022

In Situ Observations Of Fish Attraction To Light-Emitting Diodes On An Undersea Observation Deck, Makoto Tomiyasu, Yoko Tanouchi, Yasuzumi Fujimori, Minato Kaji, Takuma Hayashi, Naoto Matsubara, Hiroki Yasuma, Susumu Shimizu, Seiji Katakura

Journal of Marine Science and Technology–Taiwan

Many fisheries employ fishing lights to manipulate the behaviors of target fish and to attract them toward the light; however, relatively few long-time observations of fish attraction have been performed in the field. Here, an underwater observation deck was used to examine the differences in the fish-attracting effect of light-emitting diode (LED) lights on the number of attracted fish and on their behavior in the field, using white-edged rockfish as the target species. A total of 604 ± 324, 307 ± 203 and 171 ± 106 white-edged rockfish individuals were attracted to the observation window when it was illuminated with …

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Inter-Annual Variability In Growth And Maturation Of The Swordtip Squid Uroteuthis Edulis In Yilan Bay Off Northeastern Taiwan, Jing-Yu Chen, Tzu-Yun Ching, Chih-Shin Chen May 2022

Inter-Annual Variability In Growth And Maturation Of The Swordtip Squid Uroteuthis Edulis In Yilan Bay Off Northeastern Taiwan, Jing-Yu Chen, Tzu-Yun Ching, Chih-Shin Chen

Journal of Marine Science and Technology–Taiwan

The swordtip squid Uroteuthis edulis, distributed in the temperate and tropical neritic waters in the Indo-Pacific region, is a crucial component of marine ecosystems and is a target species of fisheries in the Northwest Pacific. Although studies have elucidated the growth and maturation of the squid in the southern East China Sea (ECS) shelf, few have assessed the population biology of the squid in waters in the vicinity of the southern ECS. We collected samples of swordtip squid from a trawler in Yilan Bay (YLB) between January 2011 and December 2012 to examine the growth and maturation of the squid …

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Study On The Improved Radiation Boundary Conditions Based On The Quadratic B-Spline Rankine Panel Method, Ming-Chung Fang, Chun-Hsien Wu May 2022

Study On The Improved Radiation Boundary Conditions Based On The Quadratic B-Spline Rankine Panel Method, Ming-Chung Fang, Chun-Hsien Wu

Journal of Marine Science and Technology–Taiwan

This study presents a higher-order Rankine source method that is based on a biquadratic B-spline scheme with an improved radiation boundary condition. This method solves flow problems under all conditions, where , including the undercritical condition ( < 0.25); this condition is present when a ship undergoes slow translational motion. The proposed method is thus more flexible than the many Rankine-source models in the literature that are applicable only to the overcritical condition ( > 0.25). Specifically, the improved radiation boundary condition is derived from upstream Seto radiation boundary conditions and by incorporating the Rayleigh damping distribution over a free surface; the improved condition is explicit and efficient for solving flow problems. In evaluations, the proposed method yields accurate solutions for unsteady flows, which are produced by an oscillating, translationally moving submerged singularity. The method is also compared …

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Sensitive Analysis Of The Static Response Of Compliant Vertical Access Risers, Fuheng Li, Haiyan Guo, Xiaomin Li, Honglu Gu May 2022

Sensitive Analysis Of The Static Response Of Compliant Vertical Access Risers, Fuheng Li, Haiyan Guo, Xiaomin Li, Honglu Gu

Journal of Marine Science and Technology–Taiwan

Compliant vertical access risers (CVARs) are considered as efficient and robust alternative options to achieve cost efficiency and safety. Design uncertainties emerge owing to the limited understanding of the effects of various parameters related to the structural properties and marine loads. In this paper, a reasonable three-dimensional (3D) numerical model of CVAR with internal flow is presented based on the slender rod theory. Accordingly, the finite element method combined with a Newton-Raphson scheme is employed to discretize and solve the equations. A sensitivity analysis is performed to investigate the influence of the structural and external load parameters on the static …

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Influence Of Boundary Conditions And Internal Fluid Types On Dynamic Characteristics Of A Deepwater Riser, Lei Guo, Zong-Ming Zhu, Zhong-Jian Pan, Zhi-Ming Guo May 2022

Influence Of Boundary Conditions And Internal Fluid Types On Dynamic Characteristics Of A Deepwater Riser, Lei Guo, Zong-Ming Zhu, Zhong-Jian Pan, Zhi-Ming Guo

Journal of Marine Science and Technology–Taiwan

Deepwater Steel Catenary Riser (DSCR) is the key structure of oil and gas production system in the ocean. To design an optimized DSCR system, the dynamic characteristics of the DSCR are analyzed by setting some different boundary condi-tions and internal fluid types. The main vibration mode of the DSCR is found orthogonal to both mass and stiffness according to the normalization condition of the main mode, and then the regular mode function and the jth order principal stiffness Kpj are obtained. Under different initial conditions, the transverse responses of DSCR represented by regular coordinates under arbitrary excitation are obtained. Then, …

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Variance Of Td-Mosaic Dual-Vortex Interactions Between In-Fa And Cempaka (2021) In The North Pacific, Tsorng-Lin Chia, Guang-Yang Pan, Ji-Chyun Liu May 2022

Variance Of Td-Mosaic Dual-Vortex Interactions Between In-Fa And Cempaka (2021) In The North Pacific, Tsorng-Lin Chia, Guang-Yang Pan, Ji-Chyun Liu

Journal of Marine Science and Technology–Taiwan

A study of the different types of dual-vortex interactions or “Fujiwara effects” between two storms is crucial for considerably improving weather forecasts. This study combined remote sensing images, empirical formulas based on the possibility of storm interaction (Liou–Liu formula), and vector addition techniques to accurately analyze In-Fa and Cempaka typhoons and the surrounding weather patterns during the 2021 typhoon season in the North Pacific. Although the distance separating the typhoons In-Fa and Cempaka was 1,800–2,040 km, the influence of middle air flow and a tropical depression (TD) caused a "vector superposition TD-mosaic double-vortex" interaction between the two typhoons. Therefore, this …

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Optimal Deployment Of Flood Emergency Response Materials Under Stochastic Demands, Shangyao Yan, Jenn-Rong Lin, Chia-Fu Ku May 2022

Optimal Deployment Of Flood Emergency Response Materials Under Stochastic Demands, Shangyao Yan, Jenn-Rong Lin, Chia-Fu Ku

Journal of Marine Science and Technology–Taiwan

This study aims to develop a planning model for the deployment of flood emergency response materials under stochastic demands. For ease of modeling, a deterministic demand model is first proposed, from which the stochastic model is further extended. These models are used to determine the allocation of materials the transport truck routes and distribution of the stockpiled materials to emergency sites. The models are formulated as multiple integer network flow problems with special side constraints which are characterized as NP-hard in terms of optimization. To solve the complicated stochastic model efficiently, we also develop a solution algorithm based on a …

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Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju May 2022

Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju

Theses and Dissertations

The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis …

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Exploring The Effects Of Varied Land Use On Elemental Concentrations Within Streams, Logan Jennings May 2022

Exploring The Effects Of Varied Land Use On Elemental Concentrations Within Streams, Logan Jennings

Biological and Agricultural Engineering Undergraduate Honors Theses

It is well documented that human activity influences the chemistry of surrounding waters. As such, it is possible that there is a link between land use within a watershed and the chemical composition of the stream. The objectives of this study are to determine if varied land use does affect the concentrations of macronutrients and trace elements present in the streams of Northwest Arkansas, and if so, to determine what extent urban and agricultural development are responsible for these changes. Water samples were collected across 19 streams in the Northwest Arkansas region between January and March of 2022. Water samples …

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Simulation, Optimization, And Economic Assessment Of Pelamis Wave Energy Converter, Hana Ghaneei, Mohammadreza Mahmoudi Apr 2022

Simulation, Optimization, And Economic Assessment Of Pelamis Wave Energy Converter, Hana Ghaneei, Mohammadreza Mahmoudi

Faculty Articles, Papers, and Other Scholarship

Wave energy and power is accessible on almost any body of water. One of the most widely known floating structures to generate renewable energy from the seas and the ocean is wave energy converter Pelamis. In this study, an attempt was made to simulate the dynamic behaviour of Pelamis P2 in the software AQWA under the influence of a nonlinear second-order Stokes wave. Pelamis P2 was simulated in different marine conditions including different water depths, wave heights, periods, and angles to assess its optimal operation. With the results in mind, it can be argued that with an increase in water …

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Using Remote Sensing Technologies In Relocating Lubrak Village And Visualizing Flood Damages, Ronan Wallace Apr 2022

Using Remote Sensing Technologies In Relocating Lubrak Village And Visualizing Flood Damages, Ronan Wallace

Independent Study Project (ISP) Collection

As weather patterns change across the world, there are communities impacted by climate change that are left unnoticed. In the Himalayan mountain range, communities have suffered, experiencing an increase in flash flooding and droughts. For Lubrak Village in Lower Mustang, the community faces the threats of flash flooding. Over the last ten years, the amount of flash flooding has increased, occurring more than once each monsoon season. After every flood, concrete-like sediment is left behind, hardening across the riverbed and increasing its elevation. As the riverbed elevation increases, this sediment encroaches on Lu-brak Village’s agricultural fields and ancient mud buildings, …

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Evaluating Climatic Influences On The Technical Performance Of Built Infrastructure Assets, Sarah L. Brown, Steven J. Schuldt, Michael N. Grussing, Michael A. Johnson, Justin D. Delorit Apr 2022

Evaluating Climatic Influences On The Technical Performance Of Built Infrastructure Assets, Sarah L. Brown, Steven J. Schuldt, Michael N. Grussing, Michael A. Johnson, Justin D. Delorit

Faculty Publications

Asset performance evaluations serve as a benchmark that can be used to make asset manufacturer selection decisions, i.e., choosing the brand of manufacturer that provides the highest performance among all brand competitors. Understanding the environmental conditions to which assets are subjected provides facility managers another data point to understand asset performance. This research builds upon a previously published performance-based manufacturer selection metric by investigating the linkage between asset performance and exposure to local climate, using chiller and air handler data from 20 United States Air Force installations. The link between environmental factors such as Heating Degree Days (HDD); Cooling Degree …

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A Non-Iteration Solution For Solving The Backward-In-Time Two-Dimensional Burgers’ Equation With A Large Reynolds Number, Yen-Shen Chang, Yung-Wei Chen, Chein-Shan Liu, Jiang-Ren Chang Mar 2022

A Non-Iteration Solution For Solving The Backward-In-Time Two-Dimensional Burgers’ Equation With A Large Reynolds Number, Yen-Shen Chang, Yung-Wei Chen, Chein-Shan Liu, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

This article proposes a noniteration solution based on the Lie-group shooting method (LGSM) to solve the backward-in-time two-dimensional Burgers’ equation with a large Reynolds number. The backward problem is famous for seriously ill-posed cases because the solution is generally unstable and highly dependent on the input data. Small perturbations in the input data, such as random errors inherent to the measurements in the analysis, can cause large oscillations in the solution. To handle a large Reynolds number under long time spans, it is very difficult to integrate towards the time direction. To avoid time integration and numerical iteration, the noniteration …

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Polyketides And Terpenes In Marine Microalgae: Ecological Roles And Mechanisms Of Biosynthesis, Yunxuan Xie, Mohammad Elsheikh Mar 2022

Polyketides And Terpenes In Marine Microalgae: Ecological Roles And Mechanisms Of Biosynthesis, Yunxuan Xie, Mohammad Elsheikh

Journal of Marine Science and Technology–Taiwan

Marine microalgae comprise a large number of polyketides and terpenes identified to date with highly diverse molecular scaffolds and the biological activities (Kalaitzis et al., 2010). These compounds play significant roles in marine food web and nutraceutical supplementation in marine animals. Compounds of this class are often synthesized by gene clusters with dedicated domains responsible for carbon chain extension and modification. The unique molecular structure of these compounds encourages people to investigate their biosynthetic mechanisms in-depth. In this review, we summarize relevant articles to unravel the shared mechanisms of these compounds to further understand the variety of domain organizations and …

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Unbaited Light-Emitting Diode Traps Performance For Catching Orange Mud Crabs, Muhamad Naimullah, Kuo-Wei Lan, Mhd Ikhwanuddin, Adnan Amin-Safwan, Wei-Yu Lee Mar 2022

Unbaited Light-Emitting Diode Traps Performance For Catching Orange Mud Crabs, Muhamad Naimullah, Kuo-Wei Lan, Mhd Ikhwanuddin, Adnan Amin-Safwan, Wei-Yu Lee

Journal of Marine Science and Technology–Taiwan

Mud crabs (Scylla spp.) are a vital fishery resource and targeted for a valuable source of income for coastal communities throughout the Indo-Pacific region. Baited traps are a considerable expense in crustacean fishing. Hence, the present study was performed to investigate the catchability of Scylla olivacea in response to light-emitting diodes (LEDs) in captivity and field conditions. We used a new experimental setup in the captivity condition that revealed most S. olivacea were attracted to green, blue, and white LED lights and no attractive effect by red LED lights similar to the controls. Field studies have shown that the catch …

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Catch And Effort Standardization For Taiwanese Swordtip Squid Uroteuthis Edulis Fisheries In The Southern East China Sea, Ke-Yang Chang, Yu-Jie Hsu, Tzu-Yun Ching, Cheng-Hsin Liao, Chih-Shin Chen Mar 2022

Catch And Effort Standardization For Taiwanese Swordtip Squid Uroteuthis Edulis Fisheries In The Southern East China Sea, Ke-Yang Chang, Yu-Jie Hsu, Tzu-Yun Ching, Cheng-Hsin Liao, Chih-Shin Chen

Journal of Marine Science and Technology–Taiwan

The swordtip squid Uroteuthis edulis is a neritic squid species that is widely distributed within the coastal waters of subtropical and tropical Indo-western Pacific regions. This squid is a commercially important species throughout its distribution range and plays a critical role in marine ecosystems. Stock assessments of the squid in the East China Sea (ECS) are scarce, although it is crucial information for the sustainability of the squid and relevant fisheries. The squid was harvested by various fisheries in the southern ECS, which could restrict methods for catch-effort standardization. In this study, catch-effort data of Taiwanese swordtip squid fisheries in …

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Uniform Torsion Analysis Of Composite Shafts Using Point Collocation Method Based On Pascal Polynomials, Chih-Wen Chang, Jyh-Hong Wu, Ying-Ru Lin, Yu-Feng Lin, Nan-Nong Huang Mar 2022

Uniform Torsion Analysis Of Composite Shafts Using Point Collocation Method Based On Pascal Polynomials, Chih-Wen Chang, Jyh-Hong Wu, Ying-Ru Lin, Yu-Feng Lin, Nan-Nong Huang

Journal of Marine Science and Technology–Taiwan

Torsion bars are important elements in the marine structure applications. The usage of the composite torsion bars has increased recently because it takes advantage of the different material property of each constituent. The current research focuses mainly on the uniform warping analysis of composite torsion shafts by using the point collocation method (PCM). The PCM is based on Pascal's triangle polynomial expansion and coupled with subdomain technique that is indispensable for the analysis of composite bars. In addition to satisfying the field equation (Laplace equation for warping function) and traction-free boundary condition for each component, the continuity conditions in both …

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Local Reinforcement Design And Safety Factor Evaluation Of Elliptical Hatch Of Pressure Hull, Guang-Min Luo, Jun-Wei Chen Mar 2022

Local Reinforcement Design And Safety Factor Evaluation Of Elliptical Hatch Of Pressure Hull, Guang-Min Luo, Jun-Wei Chen

Journal of Marine Science and Technology–Taiwan

A pressure hull is the primary pressure-resistant structure of a submarine. To safeguard the compressive strength of such a hull, local structural reinforcement is required for various hatches on the hull. Hatches are commonly reinforced through increasing the thickness of the hull regions around them; alternatively, hatch nozzle walls are connected with stiffened frames to maintain the continuity of reinforced structures. This study focused on a pressure hull with an elliptical hatch. A PD-5500 cylindrical pressure hull was used to design a cylindrical pressure hull structure, and a model of hatch nozzle reinforcement was designed using the Boiler and Pressure …

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Effects Of Dietary Lipid, L-Carnitine And L-Lysine Supplementation On The Growth Performance And Body Composition Of Epinephelus Lanceolatus Larvae, Jen-Hong Chu, Yu-Cong Hong, Angela Chien, Shyn-Shin Sheen Mar 2022

Effects Of Dietary Lipid, L-Carnitine And L-Lysine Supplementation On The Growth Performance And Body Composition Of Epinephelus Lanceolatus Larvae, Jen-Hong Chu, Yu-Cong Hong, Angela Chien, Shyn-Shin Sheen

Journal of Marine Science and Technology–Taiwan

The effects of different combinations of dietary lipid, L-carnitine and L-lysine on the growth performance and fatty acid profiles of larval grouper Epinephalus lanceolatus were evaluated. Eight treatment diets were formulated based on a 2x2x2 factorial design, namely 5 and 14% dietary oil mixture (3:1 fish oil/soybean oil), 0 and 0.5% L-carnitine and 0 and 2.83% L-lysine. Each diet was randomly assigned to triplicate groups of ten 0.08g E. lanceolatus larvae for 42 days. The grouper larvae fed with diets containing 14% lipid had significantly higher weight gain percentages than those fed with diets containing 5% lipid. The weight gain …

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Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson Mar 2022

Burn Probability And Climate Change: A Quantitative Evaluation Of The Temporal Alterations Of Wildfire, David N. Robinson

Theses and Dissertations

The intensity of extreme weather events, specifically wildfires, along the West Coast has slowly grown overtime due to atmospheric changes caused by climate change. The Air Force, though aware of the threat that is wildfire, does not currently have a quantitative way to assess the hazard to base locations. In this paper, burn probability is quantitatively calculated through the geospatial analysis programs to provide a means of assessing wildfire vulnerability. The FlamMap fire simulator generated burn probabilities for Vandenberg Air Force Base using climate data generated by the remote automated weather station on the base to highlight how the burn …

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Applications Of A Lightning Proxy To Generate Synthetic Lightning For Use In Physics-Based Image-Chain Models, Bryan G. Castro Mar 2022

Applications Of A Lightning Proxy To Generate Synthetic Lightning For Use In Physics-Based Image-Chain Models, Bryan G. Castro

Theses and Dissertations

A method of generating synthetic lightning through the use of a convective available potential energy (CAPE) times precipitation rate (P) proxy is applied over three distinct climatological zones of the world for a single warm season: central and southern AZ of the United States, central Cuba, and North Korea. Global Forecast System (GFS) 0.25° by 0.25° forecast data for June, July, and August of 2019 is used to provide 6-hourly CAPE and precipitation rate, while Global Lightning Dataset (GLD360) data for the period 2016 to 2020 is used to provide observed lightning strokes. A five-year lightning climatology study is conducted …

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Global Sporadic-E Climatological Analysis Using Gps Radio Occultation And Ionosonde Data, Travis J. Hodos Mar 2022

Global Sporadic-E Climatological Analysis Using Gps Radio Occultation And Ionosonde Data, Travis J. Hodos

Theses and Dissertations

A climatology of sporadic-E (Es) derived from a combined data set of GPS radio occultation (GPS-RO) and ground-based ionosonde soundings is presented for the period from September 2006 to February 2019. The ionosonde soundings were measured using the Lowell Digisonde International (LDI) Global Ionosphere Radio Observatory (GIRO) network consisting of 65 sites and 13,141,060 total soundings. The GPS-RO observations were taken aboard the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites and processed using two binary Es detection algorithms, totaling 9,072,922 occultations. The first algorithm is an S4 amplitude threshold calibrated to the occurrence of any blanketing Es …

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Carbon Estimation And Decision Making In Usaf Acquisition, Robert F. Gray Mar 2022

Carbon Estimation And Decision Making In Usaf Acquisition, Robert F. Gray

Theses and Dissertations

Recent executive orders and international agreements require the United States to significantly reduce its carbon and greenhouse gas emissions. The DoD is a significant contributor to the carbon emissions of the USA and will be required to reduce the emissions. Therefore, in order to make appropriate programmatic decisions the DoD needs to develop an appropriate method for estimating carbon and making programmatic decisions; trading-off carbon emissions with the traditional cost-schedule-performance metrics. This thesis examines the possibility of developing a model that can be used to estimate the carbon footprint of producing a system before detailed engineering designed have been complete.

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Feasibility Of Fireball Trail Detection Using Ground-Based Gps Receivers, Ian R. Moffett Mar 2022

Feasibility Of Fireball Trail Detection Using Ground-Based Gps Receivers, Ian R. Moffett

Theses and Dissertations

The feasibility of using GPS data to detect fireballs is analyzed by first modeling the fireball’s trail diffusion and plasma chemistry to get a resulting ion density profile of the trail over time. The signal perturbation caused by the fireball trail is simulated for a ground receiver using an analytic solution for diffraction from a Gaussian lens. Five cases were modeled with varying initial peak ion densities and altitudes taken from fireball and reentry vehicle data. This paper shows that it is feasible to detect a fireball trail using GPS if the fireball has a sufficiently high initial ion density, …

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A Critical Review Of Climate Change On Coastal Infrastructure Systems, Gregory J. Howland Jr. Mar 2022

A Critical Review Of Climate Change On Coastal Infrastructure Systems, Gregory J. Howland Jr.

Theses and Dissertations

This thesis is a response to climate threats identified by DoD report on Climate Change in 2019. A critical review of climate change literature related to coastal infrastructure was conducted to synthesize past research and to inform future research. This review intends to inform how climate change may impact infrastructure systems, how those impacts are evaluated, can the investigation be improved, and what can stakeholders learn from the outcomes. The end goal is to find climate change mitigation strategies and adaptation measures, or identify the easiest path to get to that end. The compiled information will inform civilian and military …

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A Framework For Assessing Facility-Level Vulnerability And Risk To Extreme Weather Events, Blake A. Gawlik Mar 2022

A Framework For Assessing Facility-Level Vulnerability And Risk To Extreme Weather Events, Blake A. Gawlik

Theses and Dissertations

Intensifying extreme weather events, tied to the rise in the global average temperature, put global built infrastructure at risk. This presents a daunting challenge for organizational leaders who are tasked to determine how best to adapt current infrastructure to uncertain future events. To develop adaptation plans and policies, vulnerability and risk must be downscaled to an actionable scale, such that planners, designers, and engineers can make adaptation recommendations. However, previous research has largely assessed risk at coarser scales, e.g., regional, national, or global. These assessments are informative, but do not help those tasked to lead adaptation to make detailed, actionable …

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Climate Change Risk To Coastal Airfield Stormwater Systems, Jedidiah R. Langlois Mar 2022

Climate Change Risk To Coastal Airfield Stormwater Systems, Jedidiah R. Langlois

Theses and Dissertations

Climate change is resulting in rising sea levels and increased rainfall, posing new challenges to stormwater management, particularly along coastlines. The airfield stormwater systems of Tyndall Air Force Base discharge directly into an interior bay of the Gulf of Mexico through tidal canals and ditches, creating a risk of system inundation from high tidewater conditions from sea-level rise (SLR). This study explores the performance and consequences of an inundated stormwater system from SLR during rainfall events using the EPA’s Stormwater Management Model (SWMM). One hundred and fifty-three combinations of SLR and return year storms were applied to a model of …

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