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The purpose of this project is to develop a highly flexible sub-ischial prosthetic socket with assisted-vacuum suspension for highly active persons with transfemoral amputation. The Specific Aims are to: A1. Develop a highly flexible socket with subischial trim lines; A2. Develop durable liners and sealing sleeves; A3. Develop/identify an appropriate vacuum pump; A4. Evaluate system performance with military amputees; and A5. Develop education materials. During Year 4, we completed the tasks in Aims 1, 2 and 5, completed the original and supplemental tasks in Aim 3, and are working on the tasks in Aim 4. We are ready to disseminate our technique using the plan developed as part of Task 12d. Publications are underway., The original document contains color images.

This report provides a summary of SIGAR s oversight work and an update on developments in the three major sectors of Afghanistan s reconstruction effort from July 1 to September 30, 2014.* It also includes a discussion of U.S. counternarcotics efforts in Afghanistan. During this reporting period, SIGAR published 31 audits, inspections, alert letters, and other products assessing the U.S. efforts to build the Afghan security forces, improve governance, and facilitate economic and social development. These reports identified a number of problems, including a lack of accountability, failures of planning, construction deficiencies, and other threats to health and safety. The monetary results from SIGAR s ongoing investigations totaled over $1 million from criminal fines, restitutions, forfeitures, contract monies protected, and civil settlement agreements. SIGAR investigations also resulted in 14 arrests, three indictments, four criminal informations, two plea agreements, and one sentencing in the United States. In Afghanistan, 24 individuals were barred from access to military installations, and nine employees were terminated. SIGAR s suspension and debarment program referred 44 individuals and 13 companies for suspension or debarment based on allegations that they engaged in fraud and nonperformance in contracts valued at over $398 million., QUARTERLY REPORT TO THE UNITED STATES CONGRESS

In December 2009, a study was conducted to determine how vehicle operations impact snow roads. The snow roads at McMurdo Station are the primary transport corridors to move personnel and material from the airfields servicing intra- and inter-continental flights. Thus, they are a critical transportation component and are also particularly susceptible to deterioration during warm temperatures. This study explored methodology to quantify the impact of various vehicles, tires, driving speeds, and maneuvers on snow-road conditions. The specific impacts of turning, acceleration, braking, and speed were isolated using spirals, circles, and straight-line testing on compacted snow surfaces. Portions of the active snow-road system were also used in a road course involving corners and surface roughness. Measurements included the strength of the snow surface in and between tire tracks, tire-track rut depth and width, and the height and width of the resulting snow piles adjacent to the tire tracks. The experiments yielded valuable guidance regarding what types of testing and measurements could most easily differentiate performance. Results indicate the impacts of driving speed and vehicle type, including the importance of the tire and suspension components, on preserving satisfactory snow-road surfaces through the melt season.

An integrated modeling and simulation capability for intelligent vehicles that can model desired mobility scenarios of interest, on-road or off-road, and is High fidelity Fast Scalable Flexible Adaptable Helps enhance mobility i.e., goes faster and farther

Ride control of military vehicles is challenging due to varied terrain and mission requirements such as operating weight. Achieving top speeds on rough terrain is typically considered a key performance parameter, which is always constrained by ride discomfort. Many military vehicles using passive suspensions suffer with compromised performance due to single tuning solution. To further stretch the performance domain to achieving higher speeds on rough roads, semi-active suspensions may offer a wide range of damping possibilities under varying conditions. In this paper, various semi-active control strategies are examined, and improvements have been made, particularly, to the acceleration-driven damper (ADD) strategy to make the approach more robust for varying operating conditions. A seven degrees of freedom ride model and a quarter-car model were developed that were excited by a random road process input modeled using an auto-regressive time series model. The proposed strategy shows promise as a cost-effective solution to improve the ride of a military vehicle over multiple stochastic terrains considering variation in operating weight., Submitted to SAE World Congress 2014

A complement to the development of new fuels to meet future energy demands of the U.S. Navy is the enhancement of energy density of existing fuels, thus increasing system payloads, ranges, and/or performance. Addition of energetic solid phase materials, such as boron, magnesium, or aluminum, to liquid hydrocarbon-based fuels can potentially increase energy density. Previous studies investigating the effect of energetic metal addition to liquid hydrocarbon-based fuels have produced mixed results. Boron has excellent potential as a liquid fuel additive due to its high volumetric and gravimetric heating value. Boron carbide (B4C) is widely available due to its commercial application as an abrasive. Boron particles were first tested as fuel additives in the 1950s to 1970s during rocket development and found to significantly increase fuel energy density but boron slurry combustion has problems with ignition, flame stability, and burnout. Recent advances in nanotechnology may allow for high-volume production of boron nanoparticles coated with catalysts and organics to enhance and control combustion, promote suspension and dispersion in fuel, and inhibit premature oxidation. Controlled studies on the effect of boron nanoparticle addition on fuel aerosol droplet size during group burning experiments were conducted by the U.S. Naval Research Laboratory (NRL Code 6114) and the Hawaii Natural Energy Institute (HNEI) at the University of Hawaii (UH) from 2009 to 2011. These studies were performed using a benchtop fuel burner assembly system with a Phase-Doppler-Particle Analyzer (PDPA) to investigate the effect of specific nanoparticle addition (boron, CeO2-coated boron, and CeO2) on aerosol droplet size and velocity in a JP-5 carrier fuel. Results of this study showed little to no effect of boron nanoparticle addition (2.5% weight loading) on aerosol droplet size and velocity distribution fields in the wet, or no flame, condition. Results did suggest an effect of b, The original document contains color images. Prepared in cooperation with University of Hawaii, Honolulu, HI.

This report documents the research study conducted on advanced suspension and control algorithms for U.S. Army ground vehicles. It is extremely important to isolate the vehicle body and its contents from terrain-induced vibrations. This enhancement will provide our Warfighters a less-disruptive environment, enabling them to improve their operational effectiveness. Reduced vibration enabled through a well-designed suspension system with an efficient control algorithm will permit higher vehicle speeds as well as better target-aiming accuracy in theater. Military vehicles with a high center of gravity and large variations in gross weights can greatly benefit by using advanced suspension technologies with active, adaptive preview-sensor-based control algorithms. The objective of this research study is to develop a preview-sensor-based control algorithm that can effectively work with advanced semi-active dampers, such as the magnetorheological fluid damper. This report provides a record of the research findings from this research project on advanced suspension and control algorithms for Army ground vehicles., The original document contains color images. Prepared in cooperation with Motile Robotics Inc.

Cancer tissues usually present high interstitial fluid pressures (IFP) which reduce the transport of therapeutic agents by decreasing convection from blood into cancer tissues, increasing the possibility of poor treatment outcome in breast cancer. We have tested the hypothesis that simulated microgravity, applied to mice through hindlimb suspension, would increase capillary pressure and enhance delivery of nanoparticles to tumor tissues. We showed that hindlimb suspension increases delivery of dextrans to tumors located in fat pad #4 (near pelvis, above heart level when suspended) and decrease it in tumors located in fat pad #1 (close to the neck, below heart level when suspended). Suspension increased blood flow to tumors regardless of tumor location and caused a trend (though non-significant) for reduced growth of tumors located in fat pad #4 when mice were treated with doxorubicin. These data indicate that simulated microgravity may enhance delivery of nanodrugs to tumor tissues. Further studies are necessary to better characterize these findings., The original document contains color images.

A current-carrying wire hanging between two suspension points in a transverse magnetic field adopts a shape intermediate between a circle and a hyperbolic cosine. This magnetocatenary can be analytically calculated as a novel extension of the standard hanging chain problem in an intermediate mechanics course., Published in European Journal of Physics v33 p1667-1675, 2012.

This report is required for the U.S. Army Edgewood Chemical Biological Center In-House Laboratory Independent Research project Membrane Vesicles and Extracellular Proteins in Antibiotic Resistance and Virulence . Certain extracellular proteins of pathogenic bacteria have been shown to function in survival mechanisms such as host immune system modulation (Vranakis, et al., July 27, 2011, J. Proteome Res. DOI 10.1021/pr200422f) and biofilm formation (Ostrowski, A., et al., 2011, J. Bacteriol. 193:4043). To begin to address this possibility, we have analyzed Escherichia coli O157:H7 protein fractions by liquid chromatography-tandem mass spectrometry, followed by biochemical pathway mapping using the Kyoto Encyclopedia of Genes and Genomes. The fimbriae-specific subset included proteins involved in carbohydrate metabolism, which are important in providing energy for fimbriae motion. Moreover, inositol monophosphatase (IMP), which has a role in streptomycin synthesis, and a glucose-specific phosphotransferase system (G-PTS), involved in environmental processing, were also identified. IMP, G-PTS, and a putative stress protein, recently identified in the suspension, are expected to function as part of the bacterial survival mechanisms. This research should provide fundamental knowledge regarding extracellular proteins produced by Gram-negative bacteria. The identification of molecular level components important for survival could prove useful in arenas such as vaccine and antibiotic development., The original document contains color images.

The present paper experimentally determined the evaporation characteristics of nanofluid fuels with stable suspension of carbon-based nanostructures under radiation absorption in the ultraviolet-visible range. The results show that the evaporation rates of the ethanol-based nanofluids containing multiwalled carbon nanotubes (MWCNTs) or carbon nanoparticles (CNPs) are both higher than the evaporation rate of pure ethanol. Additionally, ethanol fuel with the addition of MWCNTs has a higher droplet temperature and a higher evaporation rate than the one with the addition of CNPs or aluminum (Al). To determine the optical properties of various nanofluids, which can help to explain the observed evaporation behavior, we measured the transmission spectrum for each nanofluid, and the extinction coefficient was determined accordingly. The optical properties were also modeled using Rayleigh approximation. The importance of radiation absorption and scattering by the suspended nanostructures was identified for various nanofluids. The results show that MWCNTs are more effective than Al and CNPs for radiation absorption in nanofluid because less energy is scattered away., Published in Energy Fuels, v26 p4224-4230, 2012.

Several articles in this issue of the Journal explore opportunities to incorporate technology as a way to bring together individuals in non-traditional formats to enact positive change and develop department-wide best practices. This issue also highlights the need to adapt the best practices of private industry sectors to government operations. Private industry incentivizes streamlining and simplifying business processes do more with less. OIGs and their respective departments can address efficiencies in order to establish leaner business operations. Offices of Inspectors General should not forget the tools already available while looking toward the future. The effective usage of suspension and debarment programs discussed in this issue reiterates the value of administrative actions as well as dispelling common myths. Suspensions and debarments protect government interests by excluding companies and individuals that are not responsible from participating in federal contracts. This issue emphasizes the diverse areas of oversight of the IG community and our shared endeavor to detect and deter fraud, waste, and abuse, and promote economy, efficiency, and effectiveness in the federal government.

The goal of this research is to quantify through observations and modeling how density fronts in shallow estuarine flows impact the mobilization, redistribution, trapping, and deposition of suspended sediment. The objectives of this research program are to - implement a high-resolution, 3-dimensional, finite-volume hydrodynamic model of tidal flats field site including advanced sediment transport algorithms, - integrate and test a set of field instruments to measure density, velocity, and suspended sediment concentration at density fronts in shallow water ( 1 m), - characterize flow and suspended sediment at a density front through the tidal inundation cycle as it travels across the intertidal zone, and - combine the observations and model results to (1) quantify sediment suspension, trapping, and circulation at the front, (2) determine effects of frontal sediment transport on the net sediment fluxes in shallow estuarine settings, and (3) evaluate and improve the sediment transport model.

In this paper an omnidirectional mobile robot that possesses high mobility in rough terrain is presented. The omnidirectional robot has four active split offset caster (ASOC) modules, enabling the robot to move in any planar direction. It also possesses passive suspension articulation, allowing the robot to conform to uneven terrain. The agility of the robot is experimentally evaluated in various configurations. In addition an odometry method that mitigates position estimation error due to wheel slippage is proposed. A key aspect of the proposed method is to utilize sensory data of wheel velocity, and turning rate around each ASOC pivot shaft, along with kinematic constraints of the robot configuration. Experimental odometry tests with different maneuvers in rough terrain are presented that confirm the utility of the proposed method.

Real-time driving simulations are an important tool for verifying vehicle and vehicle component designs with a driver in the loop. They not only provide a cost effective solution but also an ability to verify designs in a safe and controlled operating environment. A real-time driving experiment has been developed for Stryker to compare the ride and handling performance of a baseline passive suspension to that of a Magneto-Rheological (MR) semi-active damper suspension. The Tank Automotive Research Development and Engineering Center (TARDEC) has integrated this new suspension into a real time vehicle dynamics model of the Stryker using the MR suspension model developed by the Original Equipment Manufacturer (OEM). Using this real-time model and the TARDEC Ride Motion Simulator (RMS), TARDEC associates, along with associates from the Stryker Program Management office and the suspension OEM were able to drive and compare the passive and MR Stryker in a virtual environment. This paper describes the simulation model, motion simulator integration, operating scenarios, terrain modeling, model validation, and subjective as well as objective results from this study., Presented at SAE Conference 2012.

Many Army vehicles require tracks in order to meet the tough mobility requirements for the Army mission profile. Modeling and Simulation (M&S) provides a large cost-savings and offers a quick turn-around when addressing vehicle performance issues. Once a baseline model is built for a given system, the model can be changed quickly to address different load or usage profiles and to determine the overall affect on the vehicle and its performance. Tracked vehicles present a number of challenges, however, due to the large number of interactions between all the track and suspension components. Prior methods for analyzing tracked vehicle performance through M&S led to either simplified vehicle models or very long compute times due to the level of detail required to properly model tracked vehicles.

Current maintenance schedules for ground vehicles are determined largely based on reliability predictions of a population of vehicles under anticipated operational loads. This approach leads to unnecessary maintenance and, in some cases, in-field failures depending on differences in the usage of individual vehicles. Condition-based maintenance is scheduled instead according to the condition of each vehicle to reduce the risk of failure and maintenance costs. However, on-board instrumentation for acquiring, processing, and storing operational data is expensive, and this data is also difficult to analyze due to variations in loading. An instrumented diagnostic cleat for diagnosing mechanical faults in ground vehicle wheel ends and suspensions is studied in this paper. The cleat excites the vehicle's dynamic response through an impulse delivered to the vehicle's front and back tires. The response of the instrumented segment of the cleat is then recorded while in contact with the vehicle's tires using accelerometers. The measured dynamic response is compared to a reference response, and anomalies that correspond to vehicle faults are then detected. This paper demonstrates that the measured response spectrum from the instrumented diagnostic cleat can be attributed to vehicle chassis modes of vibration in the frequency range below 10 Hz and natural frequencies in the free dynamic response of the cleat above 10 Hz. Tire and suspension faults are simulated in a high mobility multi-purpose wheeled vehicle and the faults are detected. Tire faults are simulated by decreasing the pressure within each tire below the manufacturer recommended level, whereas suspension faults are simulated by disconnecting each damper to mimic the effects of broken damper. The data indicates that the faults and locations of the faults are identified with 90% confidence in 7 out of 8 fault cases. Errors in the measurements are modeled to compensate for changes in vehicle speed., The original document contains color images.

The U.S. Naval Research Laboratory requested that the U.S. Army Research Laboratory s Human Research and Engineering Directorate compare the HeadGard helmet suspension system with the Marine standard A pad suspension system currently used with the lightweight helmet (LWH). The goal of this effort was to assess the HeadGard helmet suspension s ability to protect the head without compromising the user s comfort and other factors, such as fit and stability. Human factors issues, such as helmet stability, effects of helmet weight on the head, fit, sizing, system comfort, airflow, and others, were assessed. Overall, the HeadGard mounted in the LWH must be compatible with the Marine standard modular tactical vest and not hinder the user s mobility and comfort. HeadGard with the LWH must be compatible with sights and shoulder-fired weapons. The objective of this assessment was to provide the Marine Corps System Command with user feedback information about the HeadGard helmet suspension from U.S. Marines performing generic combat tasks. The results of this study proved that the HeadGard suspension was rated better than the pad suspension on several design factors during dynamic combat-related maneuvers or scenarios. The participants favored the design factors of the HeadGard suspension system, such as perceived airflow, improved design, and comfortable fit. There were no statistical differences between the suspensions during less dynamic scenarios or activities, such as weapon firing, mask and balaclava interface, sand bag filling, and suspension washing and reinstallation., The original document contains color images.

This report documents our evaluation of the effectiveness of active control algorithms in a simulation environment. Each control algorithm was applied to an identical model subjected to the same disturbance input and compared to a baseline passive suspension system and each other algorithm. The control algorithms considered include a Generalized Predictive Controller (GPC) with Implicit Disturbances, GPC with Explicit Disturbances, Linear Quadratic Controller (LQR) and LQR with Preview Control. The suspension model used was a two-degree-of-freedom (2 DOF) quarter car with two sets of vehicle parameters., The original document contains color images. Prepared in collaboration with Motile Robotics, Inc., Joppa, MD.

The original document contains color images.

In still fluid, heavy particles tend to fall and reach, after some time, a terminal velocity determined by the balance between the pull of gravity and the viscosity of the fluid. Often,plankton cells are slightly heavier than sea water, and as a consequence they tend to sink in the water column. This sinking could then take them below the euphotic layer, arresting photosynthesis. To overcome sinking, plankton have devised various types of strategies. One is swimming,that is, an active, energy-consuming self-propulsion than can oppose gravitational sinking. Other phytoplankters can modify their buoyancy, becoming, at least for some time, positively buoyant. Others can exploit the turbulence in the mixed layer, using it to stay suspended for longer times. This latter option was discussed at length by Margalef, who associated the level of turbulence in the surface layer with the type of organisms that are environmentally favoured. The terminal velocity of spherical impurities with the same density grows with the squared radius of the falling impurity. Thus, larger plankton cells tend to sink faster than smaller ones, provided they can be approximated by a somewhat spherical shape. When the turbulence in the euphotic layer is low, Margalef argued, smaller, possibly swimming phytoplankters such as flagellates are favoured as the larger species sink more rapidly out of the euphotic zone. On the other hand, when the level of turbulence is high, larger plankton can benefit from turbulent suspension and become favoured with respect to the small ones (which feel diffusion limitation of nutrients more severely). One potential problem with this view is that it is not clear whether turbulence really favours a prolonged suspension of heavy impurities. For example, the results of an experiment by Ruiz et al apparently indicate that turbulence make heavy particles sink faster than in still fluid., See also ADA544302. The original document contains color images.

This research paper addresses the ground vehicle reliability prediction process based on a new integrated reliability prediction framework. This paper is intended to provide a context for and summary of the 37 page paper published in the proceedings of at the 2010 U.S. Army GVSETS symposium, which discusses the technical details at greater length. The integrated stochastic framework combines the computational physics-based predictions with experimental testing information for assessing vehicle reliability. The integrated reliability prediction approach incorporates several computational steps to achieve reliability prediction at component and system level. The Army can use this framework to improve the reliability of the military ground vehicle fleet, including consideration of all kinds of uncertainty, especially including model uncertainty. The end result will be a tool to use in the design of a new ground vehicle for increased reliability. The paper illustrates the application of the integrated approach to evaluate the reliability of the High-Mobility Multipurpose Wheeled Vehicle (HMMWV) front-left suspension system., Presented at the Army Science Conference (ASC) (27th), held in Orlando, Florida, on 29 Nov-2 Dec 2010. Prepared in cooperation with GP Technologies, Inc., Pittsford, NY, and with University of Wisconsin, Madison, WI. The original document contains color images.

October 2009 marked the fourth anniversary of the European Union's decision to proceed with formal negotiations with Turkey toward full membership in the Union and launched the annual period when all three European Union institutions, the Council, Commission, and Parliament, were required to assess the progress Turkey had made or failed to accomplish in the accession process and to issue recommendations on whether and how the process should continue. Many "Turkey-skeptics" saw the end of 2009 as a deadline for Turkish action that would have marked a critical juncture for the future of Europe's relationship with Turkey. At issue was not only the positive progress Turkey had achieved in meeting the requirements of the EU's acquis communautaire but whether a specific lack of progress by Turkey would force EU member states into a difficult debate pitting loyalty to another member state, being shunned by a candidate for Union membership, versus Europe's long-term strategic interests in Turkey. The principal issues regarding Turkey's accession center around what the EU believes has been too slow of a pace for certain critical reforms within Turkey; a perceived ambivalence toward the EU by the current Turkish leadership; Turkey's failure to live up to its agreement to extend the benefits of its customs union with the EU to Cyprus, including the continued reluctance by Turkey to open its sea and air ports to Cypriot shipping and commerce until a political settlement has been achieved on Cyprus; and a continued skepticism on the part of many Europeans about whether Turkey should be embraced as a member of the European family. Further complicating the attitude toward Turkey was the lack of a settlement of the political stalemate on Cyprus and the ongoing debate within parts of Europe over the implications of the growing Muslim population in Europe and the impact Turkey's admission into the Union would have on Europe's future., CRS Report for Congress

During the last few years, graphene has emerged as a material of choice in various applications due its unique mechanical and electronic properties. Since 2005, Vorbeck Materials Corporation, presently the only company in the world that is manufacturing graphene in greater than ton/yr quantities suitable for industrial applications, has been working to advance the application base of graphene. We have recently demonstrated in laser protection applications, that graphene-based suspensions show non-linear reductions in the transmission of high energy laser light. In this study, methods to improve the suspension dispersion and stability were developed. In addition, parameters that yield the unique NLO characteristics of graphene suspensions and the mechanisms leading to the NLO property in graphene suspensions were investigated., The original document contains color images.

This paper describes the development of a wire suspension system for dynamic testing of missiles in a wind tunnel. The system restrains the missile, permits motion in three rotational degrees of freedom, and measures forces on the model. The apparatus allows testing of missile control systems in the wind tunnel, reducing the cost and risk of a flight test program. Hydraulic actuators control cable tension and model position. Bearings provide free roll and pitch, while yaw motion is created by the cable actuation system and a repetitive learning controller. The paper describes the cable arrangement, force balance, bearings, closed-loop hydraulic control, and the repetitive-learning controller. Two sets of tests were conducted with the BOA missile (a sidewinder variant) in the HIVAS facility at the China Lake Naval Weapons Center. The tests, conducted at M=0.4-0.6, demonstrate functionality of the system in a series of missile pitch and yaw maneuvers. The learning controller is shown to learn an s-maneuver in the yaw plane., Prepared in collaboration with the Weapons Division, Naval Air Warfare Center, China Lake, CA. Accepted for publication in the AIAA Journal of Spacecraft and Rockets; final version published in v46 n3 p624-633, May-Jun 2009.

High life cycle costs coupled with durability and environmental challenges of tracked vehicles in South West Asia (SWA) have focused R&D activities on understanding failure modes of track components as well as understanding the system impacts on track durability. The durability limiters for M1 Abrams (M1, M1A1, and M1A2) T-158LL track systems are the elastomeric components. The focus of this study is to review test methodology utilized to collect preliminary data on the loading distribution of a static vehicle. Proposed design changes and path forward for prediction of durability of elastomers at the systems level from component testing will be presented., Presented at the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), held in Troy, Michigan, on 17-22 August 2009. The original document contains color images.

A distinctive feature of unmanned and conventional terrain vehicles with four or more driving wheels consists of the fact that energy/fuel efficiency and mobility depend markedly not only on the total power applied to all the driving wheels, but also on the distribution of the total power among the wheels. As shown, under given terrain conditions, the same vehicle with a constant total power at all the driving wheels, but with different power distributions among the driving wheels, will demonstrate different fuel consumption, mobility and traction; the vehicle will accelerate differently and turn at different turn radii. This paper explains the nature of mechanical wheel power losses which depend on the power distribution among all the driving wheels and provides mathematical models for evaluating vehicle fuel economy and mobility. The paper also describes in detail analytical technology and computational results of the optimization of wheel power distributions among the driving wheels. The presented math models of a multi-body vehicle with any given number of the driving wheels and type of suspension are built on a novel inverse vehicle dynamics approach and include probabilistic terrain characteristics of rolling resistance and friction, micro- and macro-profiles of surfaces of motion. Computational results illustrate up to 15%-increase in energy efficiency of an 8x8 vehicle that is guaranteed by the optimal power distribution among the driving wheels. This technology can be applied for improving energy/fuel efficiency and mobility of tactical and combat military and unmanned robotic vehicles with mechanical and mechatronic driveline systems, vehicles with individually-driven wheels and vehicles with hybrid driveline systems., Presented at NDIA's Ground Vehicle Systems Engineering and Technology Symposium (GVSETS 2009) held in Troy, MI on 18-20 August 2009. The original document contains color images.

The goal of this project is to develop a microsystem for sorting metastatic breast cancer cells from a heterogeneous suspension of cells circulating in the blood stream. Conceptually, the technique requires the transformation of a distinguishing biochemical characteristic of the target cells, such as up-regulated cadherin phenotype, into a mechanical or electrical that makes it possible to selectively manipulate the cells on the microscale. The project includes developments of a model system of cells to evaluate cadherin-mediated cell sorting and an integrated bio-functional microfluidic system to capture target cells from heterogeneous suspensions of cells. We have succeeded in the transfection of MDA-MB-231 cells with an N-cadherin expression vector deriving a homogeneous population. An anti-N-cad functionalized surface has been shown to capture N-cad expressing prostate cancer cells (PC3N) with high degree of selectivity. An assay to characterize and a technique to control the amount of immobilized anti-N-cad antibodies on surfaces have been developed to maximize the cell capture efficiency. Microchannels with anti-N-cad functionalized surfaces have been fabricated. Under flow conditions, the capture rate is poor; however, after 15min of incubation time, the capture rate is high. Once captured, the cell/surface adhesion bond is strong enough to sustain high flow-induced shears stress., The original document contains color images.

In this research, experiments and simulations were performed to determine the effects of capacitive VS conductive coupling for the electroporation of cells. The experiment is performed with a fast risetime pulser to expose samples of cells to electric fields at peak voltage of 24.4 kV, 0.6 ns risetime, and 1.6 ns FWHM. Experiments performed compare the direct-conductive connection of the cell suspension versus a capacitively coupled cell suspension. The main conclusion of this research is that, for the parameters of this experiment, electroporation does not occur for capacitive coupling (Displacement Current): Conduction current is required for electroporation to occur.

Previous research has shown that listeners wearing the Personnel Armor System for Ground Troops (PASGT) helmet performed worse than those wearing the Advanced Combat Helmet on sound localization tasks. The PASGT has greater coverage over the ears. However, these helmets also differ in their suspension systems and profiles. Three versions of a single helmet design, differing only in the ear coverage, were compared in this study. As ear coverage increased, localization performance decreased. Most of the change was due to increases in large errors (>25-deg). In addition, these effects were tested in both "ideal" laboratory acoustics and in a moderately reverberant environment. Moderate reverberation intensified the effects of ear coverage -- improving localization performance without a helmet and impairing it the most in the greatest ear coverage condition., The original document contains color images.

TARDEC's goal is to be the Army's "Center of Excellence" for technology and engineering expertise for research, development, testing and engineering of ground vehicle power and mobility (GVPM) technologies - today and tomorrow. This briefing discusses the technologies currently being worked on and the research facilities., The original document contains color images.

Combat soldiers operate in diverse environments and face injury threats that place demands on the protective equipment systems they use to provide consistent protection throughout a range of temperatures and threat magnitudes. Protective helmets are one of those systems. In addition to protecting against ballistic threats, Army and Marine Corps ground combat helmets are now designed to absorb energy in order to reduce head injury risk from blunt impacts; previous combat helmets, such as the Personnel Armor System for Ground Troops helmet in use until 2002, were not designed to provide any tested levels of blunt impact protection. The currently used Army Advanced Combat Helmet and Marine Corps Light Weight Helmet are outfitted with a pad suspension system to protect against these threats. These pad suspension systems have been found to offer superior blunt impact protection over the older sling suspension systems. The Explanatory Statement accompanying the Consolidated Security, Disaster Assistance, and Continuing Appropriations Act of 2009 directed GAO to review ground combat helmet pads. In response, this report focuses on two objectives: (1) Who currently provides the pads used in Army and Marine Corps ground combat helmets, and how were they chosen? and (2) What efforts and research have been undertaken by the Army and Marine Corps to improve helmet pad performance and helmet technology? In addition, we have included information on servicemembers' use of helmet pads that are not approved. A timeline of events regarding helmet technology is included in the attached enclosure., Report to Congressional Committees.

The vehicle dynamics module (VEHDYN 4.0) includes many enhancements to the previously documented and released VEHDYN II model and the internally developed, but not released, VEHDYN 3.0 model. The VEHDYN 3.0 model accepted the vehicle in a settled, or equilibrium, configuration instead of the "zero-force" configuration (the force acting on each suspension spring is assumed to be zero) required by VEHDYN II. VEHDYN 3.0 also included a special suspension and a band track model that were required to model the Caterpillar 30/30 engineering vehicle. VEHDYN 3.0 was further enhanced to add several other effects including: (1) a vehicle underside interference model that computes the normal and drag forces that occur when the underside of a vehicle's sprung mass comes in contact with the terrain profile, (2) a wheel damping model which computes an additional normal force component to represent the wheel's resistance to change, (3) a vehicle-terrain interface model to allow the terrain to deform, (4) accelerating and decelerating the vehicle using tractive force-speed relations and the soil-slope resistance, (5) rotational springs for enhanced suspension beam modeling, (6) a water-vehicle buoyancy and drag model to be used when a vehicle crosses a water-filled terrain obstacle, (7) numerous new run-type options including multi-run ride and shock performance sequences, slope climbing, obstacle crossing, etc., and (8) new post processors for animation. This report documents the VEHDYN 4.0 program, including the new enhancements, the input and output files and 12 example problems., The original document contains color images. Prepared in collaboration with RBA Technical Services, 3 Shadow Wood Drive, VIcksburg, MS.

The region of the South China Sea slope and shelf present challenges because of the changing influences of typhoons, non-linear internal waves, internal tidal waves, intrusions of the Kuroshio and water mass fronts and eddies. I want to quantify the dominant spatial and temporal scales for these influences on acoustic propagation, Kuroshio instabilities, and bottom scouring and sediment suspension. It is important to present the results in ways that can be implemented by acousticians conducting simultaneous measurements and modeling., code 1 only. The original document contains color images.

The multi-axis vibration transmission characteristics of selected suspension seats were investigated in the laboratory. Subjects were exposed to a flat acceleration spectrum and two low frequency signals extracted from multi-axis acceleration data recorded at the floor of a passenger locomotive. Triaxial accelerations were measured at the floor of the vibration table and at the interfaces between the subject and mounted seat (seat pan and seat back). The transmission ratios between the overall seat pan and seat back accelerations and floor accelerations provided an effective tool for evaluating the effects of measurement site, vibration direction, and posture among the selected seating systems. The results showed that the system transfer matrix, estimated using a multiple-input/single-output model, would be less than ideal for predicting low frequency operational seat vibration when using suspension seats. The Seat Effective Amplitude Transmissibility (SEAT), estimated for the tested locomotive seats, was used to predict the weighted seat pan accelerations and Vibration Total Values for assessing a one-hour operational exposure in accordance with ISO 2631-1: 1997., Published in International Journal of Industrial Ergonomics, v38 p434-446, 2008. Prepared in collaboration with Advanced Information Engineering Services, Dayton, OH.

The goal of this research program is to develop safe and efficacious osseointegrated implants that can be implanted into our warrior amputees who have limited residual limb length, extensive heterotopic ossification or difficulty with socket suspension type systems, leaving them with a non-functional limb or limbs. The new technology is to assure skin attachment at the percutaneous site, where the implant exits the skin, to prevent infection. Strategies explored in this research are the use of porous coating biomaterials that will allow immediate skeletal and subdermal skin attachment to facilitate a single stage operation for eventual rapid patient rehabilitation. The safe and efficacious introduction of the osseointegrated implant technology for our deserving warriors is the overall goal of our program.

To isolate its acoustic sensor from the large vertical motions of the buoy at the ocean surface, a typical sonobuoy employs a low-pass mechanical filter comprising a bungee cord (spring) and a damper disk (hydrodynamic added mass and damping). If the system were to behave as a driven simple harmonic oscillator, the transfer function of vertical motion would roll off at 40 dB/decade above resonance; however, experimental systems of this sort exhibit a rolloff of approximately 30 dB/decade. Experiments have shown that the inertia coefficient CI and the drag coefficient CD of a circular disk in sinusoidal motion are in fact not constants, but depend on the dimensionless ratio of amplitude of motion to disk diameter, A/d. Incorporating this concept, the simple harmonic oscillator model has been enhanced to produce an iterative model for the transfer function of the bungee/disk system that agrees well with experimental data. Well above resonance, the model simplifies to an expression giving a 27 dB/decade rolloff., Presented at the Technical Cooperation Program, Subgroup G (Undersea Warfare) Technical Panel GTP-10 Sonobuoy Working Party (25th) held in Warminster, PA on 3-5 Dec 1990.

The miniature acoustic vector sensor (AVS) incorporates, along with a hydrophone, 3-axis accelerometers whose output can be integrated to give local fluid particle velocity information. In principle, a single AVS can give unambiguous bearing information, and multiple vector sensors used in arrays of moderate size can improve spatial resolution. The use of AVS on small autonomous vehicles holds great promise for battlespace as well as oceanographic information gathering, but there are fundamental difficulties and compromises involved in the integration with a moving vehicle of an instrument responsive to particle accelerations in the surrounding medium., code 1 only.

Develop phase/depth-resolving numerical models for bottom sediment transport and surf zone hydrodynamics. Validate these models using data measured in CROSSTEX and other field experiments. Identify the role of undertow current, steep waves and breaking wave turbulence on sediment suspension events. Develop simplified phase-resolving formulations for concentrated sediment transport, suspended load transport and its near-bed boundary conditions under breaking waves. A two-phase flow model (Hsu et al 2004; Amoudry et al. 2007) is extended to model sand transport driven by measured random wave-current forcing during CROSSTEX (Scott et al. 2007). Measured near-bed time series of flow velocities are analyzed to extract (approximately) the time series of averaged wave velocities and turbulence quantities (TKE and dissipation rate). These time series are then used to drive the two-phase flow model and to calculate and resulting sand transport from immobile sand bed to the dilute region of about 5 cm above the immobile bed. Physical experiments also provide measured suspended sand concentration in the intermediate to dilute region (volume concentration ~<15%), which can be used to identify the suspension event and to validate the numerical model. On the other hand, two-phase model results for concentrated sediment dynamics can bridge the missing information at the regime of concentration from about 15% to random-close packing (~63%), which is difficult to measure in the physical experiment., Performed in cooperation with the Univeristy of Florida, Gainesville, FL.

In the Advanced Vehicle Architecture for a Net-Enabled Combat Environment Technology Demonstrator Project (ADVANCE TDP), there is a need to define the requirements of the active suspension system and how the resulting motion affects performance and well-being (i.e. incidence and severity of motion sickness). At the request of the Director Armoured Vehicles Program Management (DAVPM), a study to investigate the effects of motion disturbance in the LAV III (light armoured vehicle) was completed. During a two-week mechanized platoon commander course held at Canadian Forces Base (CFB) Gagetown, an anonymous questionnaire concerning the rating of 1) motion sickness symptoms and 2) mood and alertness was distributed daily to all of the course participants. Although the participants were encouraged to complete the questionnaire several times each day, compliance with instructions was adversely affected by the operational and physical demands of the course. In addition, uncontrolled variables such as noise, vibration, adverse weather, stress and fatigue likely affected the scores of diagnostic motion sickness symptoms and mood. The most frequently reported motion sickness symptoms were drowsiness, feeling warm and headaches. The most frequently reported mood parameters were weariness, sleepiness, and physical discomfort. Anecdotal reports suggested that the course participants, who were experienced infantry members, had habituated to the motion of the LAV III and were thus less susceptible to motion disturbance than less experienced members.

A study for validating a time-accurate explicit finite element code for modeling fully-coupled flexible multibody systems carrying liquid-filled tanks is presented. The multibody system includes rigid bodies, flexible bodies, joints, and actuators. Rigid bodies rotational equations of motion are written in a body-fixed frame with the total rigid body rotation matrix updated each time step using incremental rotations. Flexible bodies are modeled using total-Lagrangian spring, truss, beam and hexahedral solid elements. A penalty model is used to impose the joint/contact constraints. An asperity based friction model is used to model joint/contact friction. The fluid governing equations of motion are the incompressible Arbitrary Lagrangian-Eulerian Navier- Stokes equations along with a large-eddy simulation (LES) turbulence model. The fluid's free-surface is modeled using an acceptor-donor volume-of-fluid based algorithm. Coupling between the fluid and solid is achieved by solving Newton's equations of motions at the fluid-solid interface nodes. The validation study is conducted using a multibody system consisting of a rigid baffled tank mounted on suspension springs. The springs are connected to a rigid frame mounted on two linear hydraulic-actuators. Experiments with various input ramp and harmonic excitation from the actuators are performed and the results of the experiments are compared to the results obtained using the model. The system response is measured using linear-displacement transducers at the springs and two cameras showing side and front views of the tank. The results show that the model can predict with reasonably good accuracy the test system's dynamic response., Presented at the 2007 SAE International World Congress, held in Detroit, MI in Apr 2007. The original document contains color images.

The original document contains color images.

The mathematical pendulum is one of the most widely studied problems in engineering physics. This is, however, primarily limited to the classical pendulum with a single bar and mass configuration. Extensions to this include multi-degree of freedom systems, but many of the classical assumptions, such as a single bar per mass, are preserved. Several designs used in practice utilize multiple or trapezoidal configurations to enhance stability. Such designs have not been studied in great detail and there is a need for additional work to fully analyze their response characteristics. The two-string pendulum design characteristics are initially investigated, both in terms of oscillation characteristics and string tension. Analytical and numerical methodologies are applied to predict the response of the two-string pendulum in free and forced oscillations. Validation of the results is performed by comparisons to simulations conducted with a standard commercial software package. A preliminary optimization study is conducted for a driven two-string pendulum. Finally, it is shown how to apply the results of the analysis and optimization studies developed in this work in a typical design case., The original document contains color images.

INTELLIGENT LOAD MONITORING SYSTEM: The Intelligent Load Monitoring System will provide the prime mover crew a higher level of confidence that the trailer/prime mover are not overloaded and that the cargo is properly positioned and secured to the trailer for the environment in which it is being transported. Insure mission safety by providing load information to prime mover crew (weight distribution, cube CG & corrective action) and warning of any overload conditions and (or) potential rollover situations., Document contains briefing charts (only). The original document contains color images.

The broad long-term goal of this research is to extend understanding of wave and current processes over a very rough boundary, specifically that presented by a coral reef. From this understanding we aim to develop models that account for the effects of roughness on wave dissipation, sediment transport and biophysical interactions. The objective of this project is to relate measurements of roughness over a highly irregular bottom to observations of the wave flow at various scales, with the goal of developing a relation between roughness and wave and current energy dissipation and shear stress. The specific objectives include three elements: (1) observations of the small-scale turbulent processes over a wave orbital excursion; (2) a broad scale characterization of the wave field and its response to roughness; (3) high-resolution spatial surveys of the roughness over the study region. These observations will be further extended using a numerical model of the wave field in the nearshore region. Concurrent observations of sediment load and optical properties will explore the connection between shear stress and sediment suspension and transport over the complex reef topology.

The goals of this project were to develop the technologies necessary to implement a new, non-contacting infrared sensing element. As described in our proposal, the sensing element is to be suspended in tension with electrostatic forces within a pixel cavity. The creation of this structure has required the development of a number of MEMS fabrication techniques. We have also developed new circuit topologies to the novel sensing structure., The original document contains color images.

The purpose of this DRDC dynamic biomechanical model research program is to improve the understanding of human load carriage capabilities and to understand the effects of load carriage design features on human health and mobility. This research is directed at creating a method of determining several of the biomechanical factors to be used as inputs to the Load Conditions Limit model as described in DRDC report# W7711-0-7632-01 entitled "Proposed Long Range Plan for a Research and Development Program of Dynamic Load Carriage Modeling." In the current study, a 3D solid model was split into an upper and lower torso coupled with a rigid join located at the location of the spine at the L3/L2 height. Acceleration histories of subjects wearing packs were previously recorded during human trials. Acceleration of a person was numerically integrated and used to drive the motion of the Dynamic Biomechanical Model (DBM) torso. Torso accelerations for a wide range of activities were recorded and can be used to drive these models, creating an excellent data base for many human and pack motions for current and future modeling of human motions. This technique of capturing and generating motions is applicable to many situations where an envelope of human motion and body accelerations needs to be tested to ensure equipment does not cause excessive dynamic loading on the soldier. Piecewise linear dynamic, static and creep material response models were developed for typical backpack materials. In addition, a piecewise linear model of the dynamic stress strain response for the Clothe the Soldier shoulder strap assembly was developed. The model estimates reaction forces and moments on the lumbar spine and the total shoulder reaction force. The model also calculates the distribution of force to the upper and lower torso and the total contact force., Text in English; abstract in French and English. The original document contains color images.

Mobility testing was conducted on two HMMWVs at the U.S. Army Yuma Proving Grounds by the U.S. Army Tank-automotive Research, Development and Engineering Center (TARDEC), and Davis Technologies International, Inc. (DTI) of Addison, Texas during the period of 23-27 September 2002. One of the vehicles tested was a standard HMMWV and the second was a HMMWV with a very low bandwidth active compressible fluid suspension system that was designed and installed on the vehicle by DTI. The purpose of the tests was to evaluate the possible performance benefits of the compressible fluid suspension system. Ride quality performance was quantified over three separate cross-country courses. Each vehicle s driver limited speed was also measured over discrete half-round obstacles of 4, 6, and 8-inch heights. Vehicle maneuverability was also evaluated by testing over a lane-change course and a slalom course at a variety of vehicle speeds. Limited vehicle roll down tests were also conducted to get a comparison of the rolling resistance of the two vehicles., The original document contains color images.