228 research outputs found
In the Wake of the End of the World: Stories
This collection of short stories came about from my growth as a passionate but imperfect feminist, reflecting on the place I call home—how the South and its politics shape us and how I learned to shape myself
The Use of Dietary Supplements Among Division II Collegiate Athletes
The purpose of the present study was to incorporate the Theory of Reasoned Action into the examination of Division 11 collegiate athletes and the consumption of dietary supplements. The areas that were analyzed consisted of gender differences and sport differences based on the three subscales of behavioral intentions, attitudes toward behavior, and subjective norms in the SPAADSU (Perko, 1999). Results revealed that males scored significantly lower than females on the subscales of attitude towards behavior and subjective norms. Males were more likely to agree with the questions associated with attitude towards behavior and subjective norms. Significant differences among the sports with 10 or more participants in the present study showed that women’s basketball scored higher on behavioral intentions than women’s softball and men’s football. On the subscale of attitude towards behavior, women’s basketball and women’s volleyball both scored higher than men’s baseball. Women’s basketball scored higher than women’s softball and men’s football; and women’s volleyball scored higher than women’s softball. On the subscale of subjective norms, results showed that women’s basketball scored higher compared to women’s softball. Information from the present study may be useful for healthcare professionals and/or practitioners because it will give a better understanding for the thought processes behind an athlete’s use of dietary supplements
ECDIS Development Laboratory and Navigation Technology Demonstration Center
The U.S. Navy is undergoing a major transition from traditional, paper chart navigation to computer-based electronic charting. The Chief of Naval Operations (CNO) has mandated that all Navy ships will navigate strictly through electronic means by FY07. However, due to some recent groundings, the Navy is now striving to accelerate the full implementation of electronic navigation by FY04. The Naval Oceanographic Office (NAVOCEANO) is making a concerted effort to support this transition with upgrades to state-of-the-art survey ships, instrumentation, and data processing equipment. NAVOCEANO is increasing its capability to rapidly collect and process hydrographic survey data, and to quickly produce new electronic navigational charts in co-production with MMA. In addition to ensuring safe navigation, these new products will include tactical digital overlays for bafflespace awareness. At NAVOCEANO, a new program is under development to expand these capabilities in a joint effort with University of Southern Mississippi\u27s new Hydrographic Sciences Research Program. In September 2001, an ECDIS Development Laboratory and Navigation Technology Demonstration Center will be established. This facility will conduct quality assurance (QA) and test and evaluation @&E) of electronic chart products from NAVOCEANO and other hydrographidoceanographic data providers. This facility will also assist Navy ship personnel in gaining a greater understanding of electronic charting, as well as increased technical proficiency in properly using these systems to safely navigate - particularly in the shallow littoral areas of the world. The ECDIS Development Laboratory is envisioned to become an information clearinghouse and demonstration center on electronic charting technological development. In addition to explaining the range of currently available government data products and services, The Navigation Technology Demonstration Center will showcase the use of electronic charts and its capability when used to avoid groundings and collisions at sea. The Center will The U.S. Navy is undergoing a major transition from traditional, paper chart navigation to computer-based electronic charting. The Chief of Naval Operations (CNO) has mandated that all Navy ships will navigate strictly through electronic means by FY07. However, due to some recent groundings, the Navy is now striving to accelerate the full implementation of electronic navigation by FY04. The Naval Oceanographic Office (NAVOCEANO) is making a concerted effort to support this transition with upgrades to state-of-the-art survey ships, instrumentation, and data processing equipment. NAVOCEANO is increasing its capability to rapidly collect and process hydrographic survey data, and to quickly produce new electronic navigational charts in co-production with MMA. In addition to ensuring safe navigation, these new products will include tactical digital overlays for bafflespace awareness. At NAVOCEANO, a new program is under development to expand these capabilities in a joint effort with University of Southern Mississippi\u27s new Hydrographic Sciences Research Program. In September 2001, an ECDIS Development Laboratory and Navigation Technology Demonstration Center will be established. This facility will conduct quality assurance (QA) and test and evaluation @&E) of electronic chart products from NAVOCEANO and other hydrographidoceanographic data providers. This facility will also assist Navy ship personnel in gaining a greater understanding of electronic charting, as well as increased technical proficiency in properly using these systems to safely navigate - particularly in the shallow littoral areas of the world. The ECDIS Development Laboratory is envisioned to become an information clearinghouse and demonstration center on electronic charting technological development. In addition to explaining the range of currently available government data products and services, The Navigation Technology Demonstration Center will showcase the use of electronic charts and its capability when used to avoid groundings and collisions at sea. The Center will The U.S. Navy is undergoing a major transition from traditional, paper chart navigation to computer-based electronic charting. The Chief of Naval Operations (CNO) has mandated that all Navy ships will navigate strictly through electronic means by FY07. However, due to some recent groundings, the Navy is now striving to accelerate the full implementation of electronic navigation by FY04. The Naval Oceanographic Office (NAVOCEANO) is making a concerted effort to support this transition with upgrades to state-of-the-art survey ships, instrumentation, and data processing equipment. NAVOCEANO is increasing its capability to rapidly collect and process hydrographic survey data, and to quickly produce new electronic navigational charts in co-production with MMA. In addition to ensuring safe navigation, these new products will include tactical digital overlays for bafflespace awareness. At NAVOCEANO, a new program is under development to expand these capabilities in a joint effort with University of Southern Mississippi\u27s new Hydrographic Sciences Research Program. In September 2001, an ECDIS Development Laboratory and Navigation Technology Demonstration Center will be established. This facility will conduct quality assurance (QA) and test and evaluation @&E) of electronic chart products from NAVOCEANO and other hydrographidoceanographic data providers. This facility will also assist Navy ship personnel in gaining a greater understanding of electronic charting, as well as increased technical proficiency in properly using these systems to safely navigate - particularly in the shallow littoral areas of the world. The ECDIS Development Laboratory is envisioned to become an information clearinghouse and demonstration center on electronic charting technological development. In addition to explaining the range of currently available government data products and services, The Navigation Technology Demonstration Center will showcase the use of electronic charts and its capability when used to avoid groundings and collisions at sea. The Center will have commercial-off-the-shelf ECDIS and other electronic chartbased systems. A major focus will be to provide a better appreciation of the limitations electronic chart data produced by both the government and private sector that are derived from century-old hydrographic source data. Another important aspect will be to explain the capability and limitations of using very precise electronic navigation positioning systems (e.g., GPS and Differential GPS) with electronic charting systems. The Navigation Technology Center will also demonstrate the use of tactical digital overlays to provide naval vessels with critical military information that contributes to both safe navigation and increased warfrghting mission capability
Earth's first snowball event: Evidence from the early Paleoproterozoic Huronian Supergroup
Ever since it was first proposed that the Earth completely froze during glaciations ∼ 640 million years ago evidence supporting this hypothesis has been increasing, primarily from samples of carbonates directly overlying glacial diamictites, termed cap carbonates. However, this was not the first extensive glacial period that affected planet Earth: ∼1750 million years prior to Neoproterozoic glaciations the Earth went through its first major glacial episode, the early Paleoproterozoic Huronian glaciations. The second Huronian ice advance deposited the Bruce Formation, with its overlying cap carbonate, the Espanola Formation. This up to ∼ 300 m thick succession of limestone, siltstone, dolostone and sandstone overlies diamictite containing a dropstone-bearing layer with δ13Ccarb of −10‰. The 12C-enriched interval also has rare earth element (REE) patterns with negative Eu anomalies, radiogenic Sr isotopes, and negative εNd(0) in the carbonate. The first of these observations is probably due to highly reducing conditions in the sediment, and the possible thawing of methane-rich areas, releasing fluids that mixed with the overlying bottom waters; the last two reflect the diagenetic incorporation into the carbonate of radiogenic Sr, and derivation of REEs, including Nd, from abundant silty loess. This infers a stratified water mass with a relatively stagnant bottom layer during disintegration of an ice shelf. Above this REE patterns through the basal Espanola become increasingly more light depleted upwards, C becomes heavier, Sr is less radiogenic, εNd(0) is near 0 and one area has up to ∼ 1300 ppm Ba incorporated into the carbonate, indicating breakdown of water-mass stratification. Vertically over ∼ 200 m δ13Ccarb increases from −4.5 to −2.5‰ as the environment shallowed incorporating gradually increasing amounts of seawater into the freshwater plume, which initially extended to depths below wave base. Strata deposited in the upper Espanola near the strandline contain layers of Fe-Mn-rich dolomite with positive Eu anomalies reflecting Paleoproterozioc seawater composition dominating even the nearshore by this time. These observations are similar to those from Neoproterozoic cap carbonates, and provide new evidence for the possibly snowball Earth-like nature of the ∼ 2.4 Ga Bruce glaciation
Optical Strain and Crack-Detection Measurements on a Rotating Disk
The development of techniques for the in-situ measurement and structural health monitoring of the rotating components in gas turbine engines is of major interest to NASA. As part of this on-going effort, several experiments have been undertaken to develop methods for detecting cracks and measuring strain on rotating turbine engine like disks. Previous methods investigated have included the use of blade tip clearance sensors to detect the presence of cracks by monitoring the change in measured blade tip clearance and analyzing the combined disk-rotor system's vibration response. More recently, an experiment utilizing a novel optical Moir based concept has been conducted on a subscale turbine engine disk to demonstrate a potential strain measurement and crack detection technique. Moir patterns result from the overlap of two repetitive patterns with slightly different spacing. When this technique is applied to a rotating disk, it has the potential to allow for the detection of very small changes in spacing and radial growth in a rotating disk due to a flaw such as a crack. This investigation was a continuation of previous efforts undertaken in 2011 to 2012 to validate this optical concept. The initial demonstration attempted on a subscale turbine engine disk was inconclusive due to the minimal radial growth experienced by the disk during operation. For the present experiment a new subscale Aluminum disk was fabricated and improvements were made to the experimental setup to better demonstrate the technique. A circular reference pattern was laser etched onto a subscale engine disk and the disk was operated at speeds up to 12 000 rpm as a means of optically monitoring the Moir created by the shift in patterns created by the radial growth due the presence of the simulated crack. Testing was first accomplished on a clean defect free disk as a means of acquiring baseline reference data. A notch was then machined in to the disk to simulate a crack and testing was repeated for the purposes of demonstrating the concept. Displacement data was acquired using external blade tip clearance and shaft displacement sensors as a means of confirming the optical data and for validating other sensor based crack detection techniques
Building a Cleaner, More Resilient Energy System in Cuba: Opportunities and Challenges
Cuba’s energy sector is at a crossroads. The country’s mostly fossil fuel-fired energy system faces a number of longstanding and serious challenges, including breakdowns at aging power plants, decreasing fuel imports and fuel shortages, and the growing threat of climate change-related disruptions. In recent years, Cuba has seen frequent electric blackouts and brownouts that have affected residents, businesses, and government institutions island wide.
Compounding these problems, Cuba is facing a severe economic crisis. In 2022, year-on-year inflation was 39% (down from 77% in 2021). While inflation is estimated to have dropped to 30% in 2023, the price of food increased 78%. Residents of Cuba are expected to experience a new wave of inflation in 2024 following the government’s announcement of a new austerity plan that will include price and tax increases and cuts in subsidies. Further, according to Cuba’s Minister of Economy and Planning, export earnings in 2023 were just 12 billion in 2019), missing the forecasted $9.9 billion.
Overcoming Cuba’s energy challenges amidst the economic crisis will be no small task, requiring substantial investments of capital, which have been hard to come by given real and perceived risks of investing in Cuba under current circumstances and other regulatory and legal obstacles. New policies and systemic changes, and an overall reimagining of the country’s energy system, will be essential to attract the new investment needed to enable a clean energy future.
Over the past 10 years, Cuba has begun to embark on an energy transition. Recent shifts in law and policy create new and promising opportunities and indicate a desire on the part of Cuba’s policymakers to transition to a cleaner, more climate resilient energy system. Cuba committed to generating 24% of its electricity from renewable energy sources by 2030 as part of the country’s Nationally Determined Contribution (NDC) under the Paris Agreement. Policymakers have subsequently announced their intent to increase renewable electricity generation to 37% by 2030. Additionally, in 2019, Cuba updated its constitution to explicitly state that the government must respond to climate change and aims to promote foreign investment for economic development. Cuba’s intention to transition to renewable energy generation is key, as renewables can provide climate change mitigation, reduced local air pollution, and resilience benefits over the current fossil fuel-fired power generation system.
This report provides detailed information on the current state of Cuba’s energy sector and identifies opportunities to accelerate the deployment of renewables and advance climate resilience. The information provided is intended to help support future decisions on planning and policy in Cuba, foreign policy in the United States and other countries, and private and public investment in the country’s clean energy transition
NASA Glenn Research Center Experience with "LENR Phenomenon"
Since 1989 NASA Glenn Research Center (GRC) has performed some small-scale limited experiments that show evidence of effects claimed by some to be evidence of Low Energy Nuclear Reactions (LENR). The research at GRC has involved observations and work on measurement techniques for observing the temperature effects in reactions of isotopes of hydrogen with palladium hydrides. The various experiments performed involved loading Pd with gaseous H2 and D2, and exposing Pd thin films to multi-bubble sonoluminescence in regular and deuterated water. An overview of these experiments and their results will be presented
X ray based displacement measurement for hostile environments
A new method on noncontacting, high temperature extensometry based on the focus and scanning of x rays is currently under development and shows great promise of overcoming limitations associated with available techniques. The chief advantage is the ability to make undisturbed measurements through stratified or flowing gases, smoke, and flame. The system is based on the ability to focus and scan low energy, hard x rays such as those emanating from copper or molybdenum sources. The x rays are focused into a narrow and intense line image which can be scanned onto targets that fluoresce secondary x ray radiation. The final goal of the system is the ability to conduct macroscopic strain measurements in hostile environments by utilizing two or more fluorescing targets. Current work is limited to displacement measurement of a single target with a resolution of 1.25 micro-m and a target temperature of 1200 C, directly through an open flame. The main advantage of the technique lies in the penetrating nature of x rays which are not affected by the presence of refracting gas layers, smoke, flame, or intense thermal radiation, all of which could render conventional extensometry methods inoperative or greatly compromise their performance
Replication of the Apparent Excess Heat Effect in a Light Water-Potassium Carbonate-Nickel Electrolytic Cell
Replication of experiments claiming to demonstrate excess heat production in light water-Ni-K2CO3 electrolytic cells was found to produce an apparent excess heat of 11 W maximum, for 60 W electrical power into the cell. Power gains range from 1.06 to 1.68. The cell was operated at four different dc current levels plus one pulsed current run at 1 Hz, 10% duty cycle. The 28 liter cell used in these verification tests was on loan from a private corporation whose own tests with similar cells are documented to produce 50 W steady excess heat for a continuous period exceeding hundreds of days. The apparent excess heat can not be readily explained either in terms of nonlinearity of the cell's thermal conductance at a low temperature differential or by thermoelectric heat pumping. However, the present data do admit efficient recombination of dissolved hydrogen-oxygen as an ordinary explanation. Calorimetry methods and heat balance calculations for the verification tests are described. Considering the large magnitude of benefit if this effect is found to be a genuine new energy source, a more thorough investigation of evolved heat in the nickel-hydrogen system in both electrolytic and gaseous loading cells remains warranted
Thin Film Ceramic Strain Sensor Development for High Temperature Environments
The need for sensors to operate in harsh environments is illustrated by the need for measurements in the turbine engine hot section. The degradation and damage that develops over time in hot section components can lead to catastrophic failure. At present, the degradation processes that occur in the harsh hot section environment are poorly characterized, which hinders development of more durable components, and since it is so difficult to model turbine blade temperatures, strains, etc, actual measurements are needed. The need to consider ceramic sensing elements is brought about by the temperature limits of metal thin film sensors in harsh environments. The effort at the NASA Glenn Research Center (GRC) to develop high temperature thin film ceramic static strain gauges for application in turbine engines is described, first in the fan and compressor modules, and then in the hot section. The near-term goal of this research effort was to identify candidate thin film ceramic sensor materials and provide a list of possible thin film ceramic sensor materials and corresponding properties to test for viability. A thorough literature search was conducted for ceramics that have the potential for application as high temperature thin film strain gauges chemically and physically compatible with the NASA GRCs microfabrication procedures and substrate materials. Test results are given for tantalum, titanium and zirconium-based nitride and oxynitride ceramic films
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