摘要 :
This document summarizes the research performed under AFOSR contract FA9550-08-1-0480, entitled ''Complex network information exchange in random wireless environments.'' The objective of this project was to develop novel technique...
展开
This document summarizes the research performed under AFOSR contract FA9550-08-1-0480, entitled ''Complex network information exchange in random wireless environments.'' The objective of this project was to develop novel techniques, structures, and algorithms for optimization of complex wireless networks where channels change dynamically and randomly, effecting network performance and reliability. These random dynamics, while challenging for ensuring robust high-performance network operation, also create opportunities that adaptive network control policies can exploit. This is particularly important for advanced military networks operating in rapidly changing, heterogeneous and sometimes hostile environments. A main focus of this research was to develop the new technique of Wireless Network Utility Maximization (WNUM), extending NUM ideas to include network and traffic dynamics. The research also explore optimization of network security protocols that exploit random wireless environments. Finally, compressed sensing and matrix completion ideas were explored to develop low-complexity network control.
收起
摘要 :
This project addresses the need for research on service delivery approaches for Service Members with combat-related physical or psychiatric symptoms, including Posttraumatic Stress Disorder (PTSD) and/or post-concussive symptoms. ...
展开
This project addresses the need for research on service delivery approaches for Service Members with combat-related physical or psychiatric symptoms, including Posttraumatic Stress Disorder (PTSD) and/or post-concussive symptoms. As a primary care encounter, the post-deployment health reassessment (PDHRA) process is critical to force health protection efforts. The project will develop and test the effectiveness of a sharply focused training and feedback intervention designed to increase Service member reports of behavioral health concerns and Service member acceptance of a referral for further assessment. The project has two aims. (1) Determine key elements of and short term impact of training programs for deployment related assessments. (2) Evaluate the effectiveness of a targeted training and feedback program on primary care provider s interview and clinical communication patterns related to Service member behavioral health condition identification and referrals. To accomplish these aims, a training workshop that incorporates experiential learning strategies and evidence-supported characteristics of high quality communication training programs will be piloted at 3 sites with an estimated total of 20 providers.
收起
摘要 :
Liquid resins used for molding composite structures are a significant source of hazardous air pollutant (HAP) emissions. One method of reducing styrene emissions from vinyl ester (VE) resins is to replace some or all of the styren...
展开
Liquid resins used for molding composite structures are a significant source of hazardous air pollutant (HAP) emissions. One method of reducing styrene emissions from vinyl ester (VE) resins is to replace some or all of the styrene with fatty acid-based monomers. Fatty acid monomers are ideal candidates because they are inexpensive, have low volatilities, and promote global sustainability because they are derived from renewable resources. This patented technology allows for the formulation of high performance composite resins with no more than 25 wt% styrene, which is a 25- 50% reduction in HAP emissions vs. commercial VE resins. This work validated the commercially produced low HAP vinyl ester resins from Applied Poleramics, Inc. for use in DoD composite structures. Tests have shown that the established resin formulations met the property requirements, including viscosity, glass transition temperature, modulus, strength, short beam shear strength, and fracture toughness. Furthermore the low HAP fatty acid composites have improved weatherability relative to the baseline vinyl ester composites. The Army has demonstrated and validated the use of these HMMWV transmission container, M35A3 hood, and M939 hood under laboratory testing and field conditions. The Air Force has demonstrated the production of an F-22 canopy cover, T-38 dorsal cover, and rapid prototyping splash molds. The F-22 canopy cover and splash molds were completely validated, but the T-38 dorsal cover was only validated at the laboratory level. MCM rudders were successfully demonstrated and were demonstrated at production level and validated at the laboratory level. An economic analysis has shown that these resins will cost an additional $0.1- 1.20/lb (depending on manufacturing scale) more than baseline resins. However, these resins they reduce life cycle cost by more than $1.20/lb making them economically feasible.
收起
摘要 :
We build on our earlier results (DE-FC52-06NA27324, Dreger et al., 2008; Ford et al., 2010; Ford et al., 2009a, b Ford et al., 2008) in which it has been demonstrated that regional distance moment tensor analysis can discriminate ...
展开
We build on our earlier results (DE-FC52-06NA27324, Dreger et al., 2008; Ford et al., 2010; Ford et al., 2009a, b Ford et al., 2008) in which it has been demonstrated that regional distance moment tensor analysis can discriminate explosions from naturally occurring earthquakes and mine collapses. In this project, as an effort to refine procedures for implementation we develop a more complete understanding of uncertainties, and define robust methods for their characterization. In Ford et al., 2008, it was found that populations of explosions, earthquakes and collapses in the Western U.S. separated on a Hudson et al. (1989) diagram enabling source-type discrimination. A question the current research addresses is whether these populations remain separated for other regions of the world. We have compiled a database of naturally occurring, and induced seismicity to examine the distribution of non-double-couple seismic moment tensors in a Hudson source- type diagram to be used as an a priori constraint. The results indicate the region of tradeoff between a pure explosion monopole and a compressional major vector dipole (CLVD) is relatively devoid of natural and induced seismicity, which is favorable for seismic moment tensor source-type discrimination. In addition, we present new results for the North Korean test combining regional and teleseismic observations to further restrict tradeoff between pure explosion and pure CLVD solutions for nuclear explosions. We are investigating the velocity model dependence of vanishing free-surface traction effects on seismic moment tensor inversion of shallow sources, and are working on developing a damped inversion to suppress these effects and reduce bias in scalar moment estimates for shallow sources. Finally, we are working toward extending the regional seismic moment tensor database for nuclear explosions and natural seismicity for the Korean Peninsula and Kazakhstan.
收起
摘要 :
Progress in completing planned Year 1 SOW activities has been delayed due to several factors, including: (1) delays in completing an agreed upon data use agreement for data required by Vanderbilt and Purdue to complete analyses re...
展开
Progress in completing planned Year 1 SOW activities has been delayed due to several factors, including: (1) delays in completing an agreed upon data use agreement for data required by Vanderbilt and Purdue to complete analyses relevant to the training and feedback intervention design; and (2) the 2010 NDAA Sec. 708 levied additional requirements that were not anticipated at the outset of the study, which directly impacted the study design. Despite these delays, substantial work has been completed in literature review, in psychometric analysis of materials to be used in the study, in staffing and approval processes completed, in completion of data use agreements with the Army, Navy, and Air Force, in formation and receipt of guidance by the Expert Panel, and in development of a strong working relationship among FHP&R, Vanderbilt, and Purdue. Year 2 is expected to be highly productive. Early in Year 2, it is expected that data will be received and the training and feedback intervention design will be finalized. Implementation of the pilot is expected by May, 2011 with data collection to continue for four months. This will be followed by analysis and manuscript preparation. Vanderbilt expects these activities to extend beyond the current period of performance and plans to request a one-year extension to allow adequate time to complete the SOW.
收起
摘要 :
Volatile Organic Compounds, or VOCs, are ubiquitous subsurface contaminants at industrial as well as DOE sites. At the Savannah River Plant, the principles VOCs contaminating the subsurface below A-Area and M-Area are Trichloroeth...
展开
Volatile Organic Compounds, or VOCs, are ubiquitous subsurface contaminants at industrial as well as DOE sites. At the Savannah River Plant, the principles VOCs contaminating the subsurface below A-Area and M-Area are Trichloroethylene (C(sub 2)HCl(sub 3), or TCE) and Tetrachloroethylene (C(sub 2)Cl(sub 4), or PCE). These compounds were used extensively as degreasing solvents from 1952 until 1979, and the waste solvent which did not evaporate (on the order of 2(times)10(sup 6) pounds) was discharged to a process sewer line leading to the M-Area Seepage Basin. These compounds infiltrated into the soil and underlying sediments from leaks in the sewer line and elsewhere thereby contaminating the vadose zone between the surface and the water table as well as the aquifer.
收起
摘要 :
Interconversion of various measures of zooplankton biomass have great utility in studies requiring nondestructive techniques, or for interpretation of past data. In establishing predictive relationships between such measures, the ...
展开
Interconversion of various measures of zooplankton biomass have great utility in studies requiring nondestructive techniques, or for interpretation of past data. In establishing predictive relationships between such measures, the appropriate regression to use is the geometric mean estimate, which provides a regression line in which the regressions of X on Y and Y on X are identical. The writers have employed this type of analysis in determinations on samples from diverse sea areas in different seasons and have determined that statistically significant relationships exist between carbon, wet weight, displacement volume, and dry weight when a constant technique is used. The slope of the regression line for log transformed values for carbon vs. dry weight and wet weight vs. displacement volume was sufficiently close to unity to assume a straight percentage conversion between these values. Carbon was 31-33% of dry weight and wet weight was 72-73% of displacement volume, according to these techniques. Comparability of different techniques for a biomass measurement may be poor, especially in the case of displacement volume and wet weight measurements due to variations in the interstitial water content. Moreover, interstitial water content varies inversely with total biomass density, which accounts for the absence of a simple percentage relationship between wet weight or displacement volume and other measures of zooplankton biomass.
收起
