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A trade study for an active shielding concept based on magnetic fields in a solenoid configuration versus mass based shielding was developed. Monte Carlo simulations were used to estimate the radiation exposure for two values of t...
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A trade study for an active shielding concept based on magnetic fields in a solenoid configuration versus mass based shielding was developed. Monte Carlo simulations were used to estimate the radiation exposure for two values of the magnetic field strength and the mass of the magnetic shield configuration. For each field strength, results were reported for the magnetic region shielding (end caps ignored) and total region shielding (end caps included but no magnetic field protection) configurations. A value of 15 cSv was chosen to be the maximum exposure for an astronaut. The radiation dose estimate over the total shield region configuration cannot be used at this time without a better understanding of the material and mass present in the end cap regions through a detailed vehicle design. The magnetic shield region configuration, assuming the end cap regions contribute zero exposure, can be launched on a single Space Launch System rocket and up to a two year mission can be supported. The magnetic shield region configuration results in two versus nine launches for a comparable mass based shielding configuration. The active shielding approach is clearly more mass efficient because of the reduced number of launches than the mass based shielding for long duration missions.
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Wearable technology has the potential to revolutionize the way humans interact with one another, with information, and with the electronic systems that surround them. This change can already be seen in the dramatic increase in the...
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Wearable technology has the potential to revolutionize the way humans interact with one another, with information, and with the electronic systems that surround them. This change can already be seen in the dramatic increase in the availability and use of wearable health and activity monitors. These devices continuously monitor the wearer using on--?body sensors and wireless communication. They provide feedback that can be used to improve physical health and performance. Smart watches and head mounted displays are also receiving a great deal of commercial attention, providing immediate access to information via graphical displays, as well as additional sensing features. For the purposes of the Wearable Technology CLUSTER, wearable technology is broadly defined as any electronic sensing, human interfaces, computing, or communication that is mounted on the body. Current commercially available wearable devices primarily house electronics in rigid packaging to provide protection from flexing, moisture, and other contaminants. NASA mentors are interested in this approach, but are also interested in direct integration of electronics into clothing to enable more comfortable systems. For human spaceflight, wearable technology holds a great deal of promise for significantly improving safety, efficiency, autonomy, and research capacity for the crew in space and support personnel on the ground. Specific capabilities of interest include: Continuous biomedical monitoring for research and detection of health problems. Environmental monitoring for individual exposure assessments and alarms. Activity monitoring for responsive robotics and environments. Multi-modal caution and warning using tactile, auditory, and visual alarms. Wireless, hands-free, on-demand voice communication. Mobile, on-demand access to space vehicle and robotic displays and controls. Many technical challenges must be overcome to realize these wearable technology applications. For example, to make a wearable device that is both functional and comfortable for long duration wear, developers must strive to reduce electronic mass and volume while also addressing constraints imposed by the body attachment method. Depending on the application, the device must be placed in a location that the user can see and reach, and that provides the appropriate access to air and the wearer's skin. Limited power is available from body--?worn batteries and heat must be managed to prevent discomfort. If the clothing is to be washed, there are additional durability and washability hurdles that traditional electronics are not designed to address. Finally, each specific capability has unique technical challenges that will likely require unique solutions. In addition to the technical challenges, development of wearable devices is made more difficult by the diversity of skills required and the historic lack of collaboration across domains. Wearable technology development requires expertise in textiles engineering, apparel design, software and computer engineering, electronic design and manufacturing, human factors engineering, and application--?specific fields such as acoustics, medical devices, and sensing. Knowledge from each of these domains must be integrated to create functional and comfortable devices. For this reason, the diversity of knowledge and experience represented in the Wearable Technology is critical to overcoming the fundamental challenges in the field.
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The research team composed of Arkema, Lion Apparel and University of Cincinnati (UC) successfully identified new barrier materials that exceed current technology for protective garments. These materials are novel semi- permeable m...
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The research team composed of Arkema, Lion Apparel and University of Cincinnati (UC) successfully identified new barrier materials that exceed current technology for protective garments. These materials are novel semi- permeable membranes (SPMs) based on an amphiphilic block copolymers (BCPs) blended in a high-strength host polymer. This innovation was enabled by Arkema's Blocbuilder controlled radical BCP polymerization technology, which generates tailored polymer architectures. The water transport properties and chemical warfare agent (CWA) rejection were measured at Arkema and UC. UC also developed characterization methods and computer simulation models to relate the permeation properties to the composition and nano scale morphology of the membranes.
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Relative price levels for all the U.S. states and metropolitan regions were estimated in Aten, Figueroa and Martin (2011, 2012, forthcoming 2013)1. We use the term RPPs and relative price levels interchangeably since no currency c...
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Relative price levels for all the U.S. states and metropolitan regions were estimated in Aten, Figueroa and Martin (2011, 2012, forthcoming 2013)1. We use the term RPPs and relative price levels interchangeably since no currency conversion is necessary within the U.S. This is similar to the Eurozone, but unlike the International Comparison Program (ICP) where PPPs are in different currencies. The price and expenditure inputs for the RPPs are from two sources: (1) detailed Consumer Price Index (CPI) micro-data and corresponding expenditure weights derived from the Consumer Expenditure survey from the Bureau of Labor Statistics (BLS), and (2) the American Community Survey on Housing from the Census Bureau. We focus first on the former as they cover all consumption goods and services, in addition to rents and owner-equivalent rents. The drawback of the CPI-BLS data is that they are constrained to 38 geographic index areas that correspond to large metropolitan areas and urban regions2. However, there are 207 item strata, for these 38 areas, enabling us to look in detail at the price variation for one year as well as the changes over the 2005-2010 period. In practice, we do not use the 207 item level detail for the computation of the RPPs because of the difference in coverage between the BLS index areas and more commonly used geographies such as states. We first aggregate the items to 16 expenditure classes or headings, then allocate these heading price levels and weights to the counties within the BLS areas based on the country share of money income3 in each area.
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Approximately 1.1 million persons in the United States are living with human immunodeficiency virus (HIV) infection. More than half of those infected are men who have sex with men (MSM). The National HIV Behavioral Surveillance (N...
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Approximately 1.1 million persons in the United States are living with human immunodeficiency virus (HIV) infection. More than half of those infected are men who have sex with men (MSM). The National HIV Behavioral Surveillance (NHBS) System collects risk behavior data from three populations at high risk for HIV infection: MSM, injection-drug users, and heterosexual adults at increased risk for HIV infection. Data for NHBS are collected in rotating cycles. NHBS participants must be aged equal to or greater than 18 years, live in a participating metropolitan statistical area, and be able to complete a behavioral survey in English or Spanish. Men who reported being infected with HIV or who had no male sex partners during the past 12 months were excluded from this analysis. The reporting period is June-December 2008.
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There are currently two major agencies, the Bureau of Labor Statistics (BLS) and the Bureau of Economic Analysis (BEA), that produce estimates of the cost of shelter for renters and for owners on a regular basis. In addition, the ...
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There are currently two major agencies, the Bureau of Labor Statistics (BLS) and the Bureau of Economic Analysis (BEA), that produce estimates of the cost of shelter for renters and for owners on a regular basis. In addition, the Census Bureau is conducting a nation-wide survey, the American Community Survey (ACS) of rents and owner costs on a rolling five-year basis. This paper explores the feasibility of using the public use micro-data of the ACS for a relatively simple imputation of owner-occupied rent expenditures. A larger and more sophisticated effort to obtain owner-occupied rent expenditures using various other sources of housing information is being undertaken at the Census Bureau in collaboration with BLS.
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Inspired by the immense variety of naturally curious explorers (insects, animals, and birds), their wellintegrated biological sensor-processor suites, efficiently packaged in compact but highly dexterous forms, and their complex, ...
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Inspired by the immense variety of naturally curious explorers (insects, animals, and birds), their wellintegrated biological sensor-processor suites, efficiently packaged in compact but highly dexterous forms, and their complex, intriguing, cooperative behavior, this paper focuses on 'Biomorphic Explorers', their defination/classification, their designs, and presents planetary exploration scenarios based on the designs. Judicious blend of bio-inspired concepts and recent advances in micro-air vehicles, microsensors, microinstruments, MEMS, and microprocessors clearly suggests that the time of small, dedicated, low cost explorers that capture some of the key features of biological systems has arrived. Just as even small insects like ants, termites, honey bees etc working cooperatively in colonies can achieve big tasks, the biomorphic explorers hold the potential for obtaining science in-accessible by current large singular exploration platforms.
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The main objectives of the study were to develop a satellite-monitored radio tag for use on right whales; tag up to 10 right whales; periodically relocate, observe and examine tagged whales in order to assess the accuracy of locat...
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The main objectives of the study were to develop a satellite-monitored radio tag for use on right whales; tag up to 10 right whales; periodically relocate, observe and examine tagged whales in order to assess the accuracy of locations and evaluate the performance of the tag and deployment mechanisms; provide photo documentation of the attachment methods and possible effects of the tag on the animal's physical well being and behavior; document right whale movements including residency times, migration pathways, timing and speeds; and relate the location of animals to known habitat characteristics and locations of other tagged whales to identify habitat preferences.
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This Note explains how to prepare the Logistics Decision Model (LDM) for use in subsequent analyses. This Note depends heavily on the LDM Users' Manual, which should be read first. LDM was developed by the Performance-Oriented Log...
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This Note explains how to prepare the Logistics Decision Model (LDM) for use in subsequent analyses. This Note depends heavily on the LDM Users' Manual, which should be read first. LDM was developed by the Performance-Oriented Logistics Assessment (POLA) project as part of a larger methodology. Performance-Oriented Logistics Assessment has developed a prototype methodology to help build the logistics portion of the Army five-year program. When building its program, the Army first estimates a requirement for each resource, but the price of satisfying all requirements always greatly exceeds the amount the Army can spend. Therefore, the Army prioritizes the different requirements; it decides which ones will be funded immediately and which ones will be deferred, perhaps for several years. The POLA methodology attempts to estimate the impact on combat performance of alternative investments in logistics resources. Combat performance measures thus become the common scale on which different resources are rated. If an increment of one resource has relatively little impact on combat performance and an equal-cost increment of a second resource has a large impact, the Army may prefer to satisfy less of the requirement for the first resource and more of the requirement for the second.
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POLA was intended to develop a prototype methodology to help build the logistics portion of the Army five-year program. When building its program, the Army first estimates a requirement for each resource, but the price of satisfyi...
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POLA was intended to develop a prototype methodology to help build the logistics portion of the Army five-year program. When building its program, the Army first estimates a requirement for each resource, but the price of satisfying all requirements always greatly exceeds the amount the Army can spend. Thus, the Army must next decide how much of each requirement not to satisfy. The Army has always made these decisions on somewhat arbitrary grounds, for it has never succeeded in developing tools that would systematically rate different resources, intended to support disparate functions, on common scales. The POLA methodology attempts to rectify this lack of estimating effects on combat performance of alternative investments in logistics resources. Combat performance is measured in terms of forward line of troops (FLOT) movement, Red and Blue weapons engaged and attrited, and Red and Blue resources consumed and personnel lost. Logistics resources considered include stocks of ammunition, petroleum, oil, and lubricants (POL), war reserve equipment, and replacement personnel. Also considered are resources that increase Combat Service Support (CSS), capacities, such as capacities to handle ammunition, transport dry cargo, etc.
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