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In previous work as part of ONR grant N000141210139 a unique automatic classifier developed by the PI that uses perceptual signal features features similar to those employed by the human auditory system was employed to successfully classify anthropogenic transients, and vocalizations from five cetacean species. Although this is a significant achievement, successful implementation of this (or any) classifier requires that it be temporally and spatially robust. The primary goal will be to address the question: Will it work on vocalization data from these species collected under different environmental conditions? To examine this, discriminant analysis will be used to rank the aural features in terms of their ability to separate the vocalizations between species. Then, the more highly ranked features will be tested for robustness. This will be done by performing a propagation experiment using cetacean vocalizations and synthetically generated calls as source signals, and testing the received signals with the classifier. The measurements will be complemented by comparing experimental results to propagation model results with the goal of generalizing the results to other ocean environments.

The attenuation of light near the seabed in the coastal ocean is affected by the concentration, size and composition of suspended particulate mass. Our research demonstrated that the effect of size is reduced considerably by the packaging of suspended particles into particle aggregates for which particle mass scales with particle area rather than with particle volume. Reduced sensitivity to size makes light attenuation a useful proxy for suspended particulate mass in many environments. Variation is the attenuation to mass ratio, however, does exist among and between environments, however, and the source of the variation remains unclear. Our research demonstrated that, on average, variable particle composition accounts for a factor of two variation in the beam attenuation to mass ratio, which does not fully explain observed variation. This finding indicated that particle packing geometry determines the light scattering properties of particles. Initial analysis of an optical proxy for particle packing geometry showed some promise.

The goal of the proposed work is to investigate the accuracy of a new method for estimating the bulk density of suspended particles in situ and non-invasively. The new method uses the commercially available LISST-100x particle size analyzer paired with a digital floc camera. It would enable collection of high temporal resolution estimates of particle bulk density.

Long-term Goals: The goal of our research is to improve our ability to assess and predict the distribution of water column optical properties in the coastal region. Objectives: Our research in the New River Tidal Inlet had three primary objectives: 1. Measure the variability of optical properties in-space along a river mouth/inlet and observe the variability in time at a single position over a tidal cycle; 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particle size distribution; 3. Relate the optical properties to the ocean reflectance, so algorithms to invert surface color to in-water constituents can be tested and improved.

Our research in the mouth of the Columbia River has four primary objectives: 1. Measure the variability of optical properties in-space in the mouth of the Columbia River on ebbing and flooding tides during a high flow period; 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particle size distribution; 3. Relate the optical properties to the ocean reflectance, so algorithms to invert surface color to in-water constituents can be tested and improved; 4. Investigate sediment parameters that optimize fit between derived suspended sediment distribution in the Columbia River mouth and the distribution produced by Delft-3D.

Magnetostrictive alloys are novel smart materials that exhibit dynamic coupling of magnetic and mechanical properties. The dynamic magnetic-mechanical coupling phenomenon may make magnetostrictive alloys useful for transforming kinetic energy into magnetic energy to be harvested for electrical energy (and vice versa). This offers the potential for magnetorestrictive alloys to be useful for the development of efficient, cost-effective transducer, actuator, smart structure, vibration dampening, and energy harvesting materials for military applications. Several low-cost processing approaches that produce highly textured thin-form magnetorestrictive Fe-Ga alloys were found to be promising for energy harvesting applications. Dalhousie University was contracted to evaluate several techniques for the production of magnetically active alloys and to evaluate the resultant thermal, magnetic, and crystallographic properties of the alloys. This document summarizes the principal results from the final two years of the project, focusing primarily on the development of Fe-Ga magnetorestrictive alloys. Mechanical alloying (via ball milling) and rapid quenching (ribbon casting) were shown to be cost-effective methods for producing Fe-Ga compositions. The magnetic and crystallographic structures were fully characterized and show unique properties. Fe Mossbauer hyperfine fields were shown to be particularly sensitive to atomic scale clustering (as a precurser to ordering). Highly-oriented feedstock Fe-Ga rods were produced using the cost-effective suction extraction method. Fe-Ga rods provided excellent feedstock material that improved the quality (i.e., 100 texture) of DRDC's fabricated Fe-Ga magnetorestrictive wire., Text in English; Abstract and Executive Summary in English and French.

The goal of this research is to develop greater understanding of how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column., The original document contains color images.

The goal of our research is to improve our ability to assess and predict the distribution of optical properties in the coastal region. Our research in the New River Tidal Inlet had three primary objectives: 1. Measure the variability of optical properties in-space along a river mouth/inlet and observe the variability in time at a single position over a tidal cycle; 2. Relate this variability to the concentration and dynamics of dissolved and particulate materials, including variability in the particle size distribution; 3. Relate the optical properties to the ocean reflectance, so algorithms to invert surface color to inwater constituents can be tested and improved., The original document contains color images.

The goal of our Tidal Flats research is to expand our understanding of the erosional and depositional processes that lead to exchange of mud between tidal channels and tidal flats. We also investigate the effect of sediment texture on sediment strength. Our research on Tidal Flats DRI had three primary objectives: 1. Improve understanding of how turbulence and sediment concentration affect the size-dependent depositional flux of sediment to the seabed on tidal flats. Based on our observations during the project, this objective has been broadened to include the effect of rainfall and runoff. 2. Improve understanding of how sediment texture and sorting in the seabed affect the size dependent erosional flux from the seabed on tidal flats. 3. Link our understanding of erosional and depositional sorting to spatial and temporal patterns of grain size on tidal flats.

The goal of this research is to develop greater understanding of how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. Objectives: 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields., Prepared in cooperation with Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada.

My long-term goal is the development of a data assimilative model system in which optical observations are linked directly and mechanistically to predictions of biological, chemical and physical dynamics of the ocean. The primary objectives are: 1. Continue to develop optical proxies for biological properties and processes in the upper ocean. 2. Establish a framework for modeling the dynamics of optical properties in the ocean, directly and mechanistically. 3. Integrate optical dynamics into state-of-the-art ocean models.

The long-term goal is a quantitative and mechanistic understanding of the response of mud flat sediments to tangential and normal stresses and how these relate to the erosion rates of sediments. The rate of muddy sediment erosion is very difficult to predict, yet it is crucial to know in predicting the evolution of mud flats as a result of natural or anthropogenic perturbations. Our objective is to determine if fracture strength alone or in combination with other geotechnical properties of muddy sediments is a predictor of erodibility., FY10 Annual Reports of S & T efforts sponsored by the Ocean Battlespace Sensing S & T Department of the Office of Naval Research. The original document contains color images.

The analysis and evaluation of the network traffic passing over NATO's communication networks is an important yet daunting task for its operators, analysts and system security officers due to the volume and complexity of the data. The following report presents ongoing work in the development of an extensible suite of network traffic visualization tools, called FloVis, that aims to address these issues. FloVis is a visualization framework designed to incorporate different network visualizations seamlessly, as plugins, under one application. The current iteration of the toolset is described below which uses visualization as a mechanism for capturing different aspects of network traffic. Each tool allows the analyst to understand/interpret/model the data in a different but related way. By combining them under the FloVis framework, the analyst has integrated access to each view to help focus his investigation onto areas of interest. As a demonstration of FloVis' effectiveness and its potential, examples have been provided below which illustrate how it can be used for understanding network traffic and detecting security events., See also ADA564697. Information Assurance and Cyber Defence (Assurance de l'information et cyberdefense). RTO-MP-IST-091

Aspects of visual alerts were explored to determine what type of visual alerts best captured attention, as measured by reaction time (RT) to the alerts. In part 1, flash rate of alerts was explored to determine the most effective detection. The results suggested that flashing at any of the flash rates was no better than a non-flashing alert. In part 2, the cost of moving an alert from one location to another was investigated. The results showed an alert location-switching cost (slower RTs after switch) that was only present for inexperienced and older participants. In part 3, the relationship between eye-location and cursor location was explored. The goal of this research was to determine if cursor-location was a good proxy for eye-location during a multidisplay task that had been used in previous experiments. The results suggested that, for this task, the cursor was in fact an excellent proxy for eye-location with a very high display correspondence between eye and cursor location. Both eye and cursor were found to move from one display to another at the same time. The results have implications for future visual alerting research and the design of automated alerting., The original document contains color images.

The goal of this research was to develop greater understanding of the how the flocculation of finegrained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. OBJECTIVES 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields.

Defence Research and Development Canada (DRDC), a special operating agency of the Department of National Defence, contracted Dalhousie University to support the development of a management accountability framework (MAF) as part of DRDC's EXPEDITION 09 organizational change project. The DRDC MAF used the Treasury Board MAF as a model, with Expectations, Indicators and Measures tiers. The proposed DRDC MAF reflects the DRDC vernacular and utilizes a survey instrument to assess managerial cadre performance directly, rather than using policies and standard operating procedures as proxies for organizational performance. Pilot studies were used to test the survey instrument approach against the six core elements of the DRDC MAF: Policy and Programs; People; Service; Risk Management; Stewardship; and Accountability. The results of the pilot studies confirm the feasibility of the survey-based approach and provide a first assessment of DRDC's organizational performance against indicators for the elements of the proposed DRDC MAF., The original document contains color images.

Defence Research and Development Canada (DRDC), a special operating agency of the Department of National Defence, contracted Dalhousie University to support the development of a management accountability framework (MAF) as part of DRDC's EXPEDITION 09 organizational change project. The DRDC MAF used the Treasury Board Secretariat MAF as a model, with Expectations, Indicators and Measures tiers. In Cycle 2 of the contract, full Indicator and Measures tiers were developed, and the Expectations tier developed in Cycle 1 was refined. In Cycle 2, two pilot studies were conducted using web-based surveys of the DRDC management cadre. The first pilot of Cycle 2 evaluated the Risk Management and Accountability elements. The second pilot of Cycle 2 evaluated Policy and Programs and Service elements, and re-evaluated the Stewardship element from Cycle 1. The results of the pilot studies confirm the feasibility of the survey-based approach and provide a partial first assessment of DRDC's organizational performance against indicators for the elements of the proposed DRDC MAF., The original document contains color images.

ACTIVITY TYPES: Commercial shipping; Commercial fishing; Commercial recreational; Aquaculture; Ferries; Cruise ships; Private recreational., Maritime Domain Awareness and Counter Piracy, 26-29 October 2009, Ottawa, Canada. Document consists entirely of briefing charts. U.S. Government or Federal Rights License. The original document contains color images.

LONG-TERM GOALS: The long-term goal is a quantitative and mechanistic understanding of the response of mud flat sediments to tangential and normal stresses and how these relate to the erosion rates of mud flats. OBJECTIVES: The rate of muddy sediment erosion is very difficult to predict, yet it is crucial to know in predicting the evolution of mud flats as a result of natural or anthropogenic perturbations. Our objective is to determine if fracture strength alone or in combination with other geotechnical properties of muddy sediments is a predictor of erodibility.

Since its independence in 1947, Pakistan has suffered a half-dozen coups d'etat, several armed independence movements, growing extremism and Islamicization within the population, and system-wide corruption and lack of political institutionalization. Yet, the question of its future continues to arise as it once again teeters on the brink of failed statehood. A crucial turning point for Pakistan, the November emergency encompassed multiple areas of state failure, including an out-of-control insurgency, loss of sovereignty within the border areas, and the seizing of both parliament and the judiciary. Despite these events, Pakistan has managed to bounce back from imminent state failure, engaging in elections and forming its current government in February 2008. Despite its claims, this new government is no exception to Pakistan's pattern -- its beginnings marred with decisions surrounding the constitutionality of the president's office and the Supreme Court, its inability to deal with an insurgency that has moved far enough inland to threaten Islamabad, and more recently, its growing economic crisis. These conflicting outcomes are at the heart of this article, where one argument claims that Pakistan is only now emerging from its colonial past, coming to terms with the contest between its Islamic and secular identities. Conversely, others argue that Pakistan is in decline -- a state increasingly incapable of addressing its internal political crises -- and the aftermath of the November 2007 emergency is an example highlighting Pakistan's state failure. What then explains Pakistan's oscillation between state failure and stability? Centered on the time frame after the November emergency, this article introduces the concept of the "stability/instability paradox" to better explain Pakistan's oscillation and persistence as a state. Its conclusion analyzes a number of determinants for Pakistan's future stability and the security of the international system., See also ADA510198. Published in Strategic Studies Quarterly, v3 n4, p22-48, Winter 2009.

The goal of this research is to develop greater understanding of the how the flocculation of fine-grained sediment responds to turbulent stresses and how this packaging of sediment affects optical and acoustical properties in the water column. OBJECTIVES: 1. Quantify the effects of aggregation dynamics on the size distribution of particles in the bottom boundary layer; 2. Quantify how changes in particle packaging affect the optical and acoustical properties of the water column. 3. Develop models describing the associations between particle aggregation, stress, and the acoustical and optical fields., Prepared in cooperation with Bedford Institute of Oceanography, Dartmouth, Nova Scotia.

The long-term goal of this study is a quantitative and mechanistic understanding of the response of mud flat sediments to tangential and normal stresses and how these relate to the erosion rates of mud flats. The rate of muddy sediment erosion is very difficult to predict, yet it is crucial to know in predicting the evolution of mud flats as a result of natural or anthropogenic perturbations. Our objective is to determine if fracture strength of muddy sediments is a predictor of erosion rate. Work was conducted at the Willapa Bay, Washington, study site. The work consisted of the following: (1) measure the values of the primary elastic geotechnical parameters (Young's modulus) as functions of sediment depth, organic matter content, temperature, grain size, and porosity; (2) determine the fracture strength of these sediments using our in situ probe; and (3) establish any correlations between these various parameters using linear elastic theory and LEFM.

The long term goal is a quantitative and mechanistic understanding of the relationship between infaunal ecology and the consequent modification of sediments, including the creation and destruction of heterogeneities and the modes and rates of sediment component mixing., code 1 only.

Our long term goal is a quantitative, mechanistic and predictive understanding of the dynamics of bubbles and bubble populations in marine sediments. We believe that this information can be used to improve and test acoustic backscatter models for gassy sediments and to better understand the ebullitive flux of methane, an important greenhouse gas, to the atmosphere., code 1 only.

The long-term goal is to quantify ripple and ripple field properties in response to wave and current hydrodynamic forcing and grain size variability. The overall objective of the 2007 experiment at the Martha's Vineyard Coastal Observatory (MVCO) is to investigate the relative adjustment of ripples in the coarse and fine sands to forcing events involving a range of different surface gravity wave and mean current forcing conditions, as a function of cross-shore distance (i.e. water depth). Our primary objective is to determine the temporal and spatial evolution of wave-forced seafloor ripple geometry and as a function of both hydrodynamic forcing (as modulated by water depth) and grain size (fine and coarse sand). The observations will be used to validate existing models and to develop new models for ripple geometry as a function of forcing hydrodynamics and seabed characteristics. The observations will also have a smaller focus on small scale sediment transport processes over ripples and larger scale wave field variability over spatially variable ripples. The small scale sediment transport process observations, which combined with realistic transport - morphodynamic models being developed by other investigators, will lead to physics-based models of ripple evolution. Wave models, initiated with the measured wave directional spectrum offshore, will be used to generate predicted wave fields for comparison to co-located observations of wave and ripple properties across the shoaling region, in both fine and coarse sand. These results will provide the basis for extending ripple property predictions based on the modeled waves to the full experimental domain. These predictions will be tested against the sidescan/multibeam survey data.

The central goal of this research is a deeper understanding of bed state adjustment in mobile sandy sediments on the inner continental shelf, and in particular the adjustment(s) to the combined effects of variable fluid forcing and biological reworking of the sediment surface. The work is motivated by the lack of a suitable observational basis for developing and testing models of the temporal evolution of the seabed roughness spectrum resulting from fluid-sediment-biological interactions in environments subjected to transient wave forcing events. Our primary objective in this first phase of the project is to quantify the rates of ripple degradation and seabed roughness change arising from biological activity on and within the seafloor. The second objective is to compare the measured degradation rates to those predicted by analytic and numerical models of bed roughness change by biological organisms, as a function of spatial frequency spanning the ripple band.

The central goal of this research is a deeper understanding of the dynamic adjustment of mobile sandy sediments to the variable fluid forcing the nearshore zone and inner continental shelf at small (1-cm to 10-m) and intermediate (10-m to 100-m) horizontal scales. The effort is motivated by the dual need to develop more realistic models of fluid-sediment interactions in these environments, and for suitable measurement techniques to make the observations necessary to adequately test the models. The objective of the proposed project is to advance the state-of-the-art of acoustic remote sensing systems for sediment and fluid dynamics studies in the wave-current bottom boundary layer. The particular focus of this project is the remote (and routine) measurement of bottom stress in energetic combined flows above mobile beds., Prepared in cooperation with Memorial University of Newfoundland, St. John's.

The development of an individual-based model (computer code) of sediments and organisms that utilizes biologically relevant parameters, such as animal sizes, population density, feeding and locomotion rates and probabilities for observed behavior, to drive the model and produce predictions about sediment composition and fabric. Biologically active sediment is represented on a computer as a regular lattice of quasi-particles with individually assigned chemical, biological or physical properties. Modal benthic organisms are introduced in the form of automatons, i.e., programmable entities, that are capable of moving through the particle lattice by displacing or ingesting-defecating particles. Each automaton obeys a set of rules, both deterministic and stochastic, designed to mimic real organism behavior, with different types of organisms having different sets of rules., The original document contains color images.

Our long term goal is a quantitative, mechanistic and predictive understanding of the dynamics of bubbles and bubble populations in marine sediments. We believe that this information can be used to improve and test acoustic backscatter models for gassy sediments and to better understand the ebullitive flux of methane, an important "greenhouse gas", to the atmosphere., The original document contains color images.

The objective of the proposed project is to advance the state-of-the-art of acoustic remote sensing systems for sediment and fluid dynamics studies in the wave-current bottom boundary layer. The particular focus of this project is the remote (and routine) measurement of bottom stress in energetic combined flows above mobile beds., Prepared in collaboration with the Department of Physics and Physical Oceanography at Memorial University of Newfoundland, St. John s, NF. The original document contains color images.

Our long term goal is a quantitative, mechanistic and predictive understanding of the dynamics of bubbles and bubble populations in marine sediments. We believe that this information can be used to improve and test acoustic backscatter models for sediments and to better understand the ebullitive flux of methane, an important greenhouse gas, to the atmosphere., The original document contains color images.

The goal of this research is to develop greater understanding of the dynamics of fine-grained sediment and its role in the generation of sedimentary facies on the continental shelf. In particular, we seek greater understanding of the environmental processes that influence the degree of packaging of fine-grained sediment within flocs (floc fraction), and the role of boundary shear stress in determining the change in sediment size and sorting that makes the sand-mud transition recognizable acoustically as well as lithologically., Prepared in collaboration with Fisheries and Oceans Canada at the Bedford Institute of Oceanography, Dartmouth, Nova Scotia. The original document contains color images.

The long term goal is a quantitative and mechanistic understanding of the relationship between infaunal ecology and the consequent modification of sediments, including the creation and destruction of heterogeneities and the modes and rates of sediment component mixing., The original document contains color images.

The goal of this research is to develop greater understanding of the dynamics of fine-grained sediment and its role in the generation of sedimentary facies on the continental shelf. In particular, we seek greater understanding of the environmental processes that influence the degree of packaging of fine-grained sediment within flocs (floc fraction), and the role of boundary shear stress in determining the change in sediment size and sorting that makes the sand-mud transition recognizable acoustically as well as lithologically., Prepared in collaboration with Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia.

The central goal of this research is a deeper understanding of the dynamic adjustment of mobile sandy sediments to the variable fluid forcing the nearshore zone and inner continental shelf at small (1cm to 10m) and intermediate (10m to 100m) horizontal scales. The effort is motivated by the dual need to develop more realistic models of fluid-sediment interactions in the nearshore zone and on the continental shelf, and for suitable measurement techniques to make the observations necessary to adequately test the models. The objective of the proposed project is to advance the state-of-the-art of acoustic remote sensing systems for sediment and fluid dynamics studies in the wave-current bottom boundary layer. The particular focus of this project is the remote (and routine) measurement of bottom stress in energetic combined flows above mobile beds., Prepared in collaboration with the Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John s, NF, Canada.

The goal of this research is to develop greater understanding of the dynamics of fine-grained sediment and its role in the generation of sedimentary facies on the continental shelf. In particular, we seek greater understanding of the environmental processes that influence the degree of packaging of fine-grained sediment within flocs (floc fraction), and the role of boundary shear stress in determining the change in sediment size and sorting that makes the sand-mud transition recognizable acoustically as well as lithologically., Prepared in cooperation with Bedford Institute of Oceanography, Dartmouth, Nova Scotia, Canada.

Double-diffusive convection, at first considered an "oceanographic curiosity," has fascinated fluid dynamicists for a generation. This is partly because some early and basic questions have still not been answered. The most practical of these - whether double diffusion is important in the ocean - was raised in the defining paper, when Stern (1960) wrote "future studies of this model ... will determine whether the proposed mechanism is significant in the vertical mixing of the sea." This question of significance has not been answered yet, and may not be until we can answer a host of fundamental questions about mechanisms and interactions, some of which are highlighted here., Original contains color plates: All DTIC reproductions will be in black and white. Presented at the 'Aha Huliko'a Hawaiian Winter Workshop (12th) held in Honolulu, HI on 16-19 Jan 2001, p191-198. This article is from ADA412459 From Stirring to Mixing in a Stratified Ocean. Proceedings Hawaiian Winter Workshop (12th) Held in the University of Hawaii at Manoa on January 16-19, 2001

A two-dimensional biomechanical model of a backpack has been developed which incorporates the primary forces at the shoulder and waistbelt contact points. The model had been validated using instrumented manikins in laboratory experiments. The computer-based formulation allows the user to specify parameters for certain pack features, such as pack mass and volume, and it predicts the resulting contact forces on the bearer. By treating some parameters as decision variables, such as the location of attachment of the shoulder straps to the pack, the model can be used as an optimization tool to achieve a specified objective, such as minimizing the total forces on the bearer. A base case analysis and some van ants illustrate this type of analysis. For the example provided, it is not possible to find a feasible solution within the prescribed shoulder-to-waist load ratio. By freeing up other variables, several alternative solutions are presented. This model can be used to easily examine trade-offs iii certain pack design decisions., The original document contains color images. Pres: RTO Human Factors and Medicine Panel (HFM) Specialists' Meeting, Kingston, Canada, p25-1/25-12, 27-29 Jun 2000. This article is from ADA394945 Soldier Mobility: Innovations in Load Carriage System Design and Evaluation (la Mobilite du combattant: innovations dans la conception et l'evaluation des gilets d'intervention)

This project attempted to determine the physiological and biomechanical effects of varying the centre of gravity of a load in a backpack in a short duration activity. Experienced soldiers (n=22) carried a 36.0 kg modified US Army ALICE backpack on a treadmill at 5.6 km/h for 15 minutes at 0% elevation. The subjects carried the load in three locations in a backpack (a high, middle and low distribution) and employed a load carriage vest as an alternative' distribution. This 'alternative' distribution balanced the load on the front and back of the subject. Oxygen consumption results showed no statistically significant difference between load locations (P= 0.621). Biomechanical analysis of the trunk lean and minimum included hip angles indicated significant differences between all alternative' comparisons as well as between the low and high load locations (P<0.05). Maximum knee flexion angles were also shown to be significantly different between the low and alternate conditions. Cadence, stride length and displacement of the body COG did not show significant differences between conditions. Subjective evaluation indicated a strong preference for the alternative load condition due to the overall increased mobility and decreased feeling of discomfort. under the conditions tested in this study it was concluded that load location does not significantly affect oxygen consumption but had a large impact on the perception of each load trial. A longer duration activity that imposes a larger strain on the subjects would be required to confirm this oxygen cost finding. The effect that trunk lean and the flexion angles will have on fatigue and energy consumption in a long-term exercise scenario has not been determined but should be undertaken in future studies. The subjective impact on the subjects should be considered as highly important and should therefore have an impact on the future design of load carriage systems., The original document contains color images. Pres: RTO Human Factors and Medicine Panel (HFM) Specialists' Meeting, Kingston, Canada, p4-1/4-6, 27-29 Jun 2000. This article is from ADA394945 Soldier Mobility: Innovations in Load Carriage System Design and Evaluation (la Mobilite du combattant: innovations dans la conception et l'evaluation des gilets d'intervention)

The central goal of this project is a deeper understanding of the dynamic adjustment of mobile sandy sediments to fluid forcing in and near the surf zone at small (1cm to 10m) and intermediate (10m to 100m) horizontal scales. The effort is motivated by the dual need to develop more realistic models of fluid-sediment interactions in the nearshore zone, and for suitable in situ measurement techniques to make the observations necessary to adequately test the models. The primary objectives of this project are: (1) to study the role of bedforms of different characteristic spatial pattern and scale in the local sediment flux and momentum balances, and (2) to investigate bedform genesis, growth, migration, and decay in relation to the fluid forcing conditions and predicted sediment transport rates. Of particular interest are the relationships between sediment fluxes, bedform properties, and asymmetries in the fluid motions. A key initial objective was to obtain a comprehensive set of measurements of bed adjustment through time, as a function of cross-shore position, and over a period of several months. This data set was obtained in SandyDuck, and is providing a basis for determining cross-shore differences in response synoptically, and for differences in the response trajectories through time and between forcing events, over a suitably wide range of conditions.

Our long term goal is a quantitative, mechanistic and predictive understanding of the dynamics of bubbles and bubble populations in marine sediments. We believe this information can be used to improve and test acoustic backscatter models for sediments and better understand the ebullitive flux of methane, an important greenhouse gas , to the atmosphere. The immediate objective is a working model for the growth of a single, isolated bubble in a marine sediment, validated with bubble growth data obtained in laboratory studies and with in situ data. We have a strategy of coordinated laboratory and modelling research to achieve our objective. The laboratory work (directed by Bruce Johnson and assisted by Bruce Gardiner and Regine Maass) aims to determine the size that bubbles can attain in sediments, internal variables like pressure, and the dynamic response of sediments to bubble growth. The modelling research (Bernard Boudreau and Bruce Gardiner), guided by the laboratory results, is developing appropriate model(s) for observed bubble growth., Prepared in collaboration with the School of Ocean and Earth Sciences, University of Southampton, Southampton, UK.

We investigated neurotransmitters which play a role in conveying light information to the circadian clock in the suprachiasmatic nucleus (SON). We studied the effects on SON cell responses to light of classic small-molecule transmitters, such as glutamate, serotonin and acetylcholine, as well as a number of peptides. We showed that glutamate can affect SON cell firing rates through both ionotropic and metabotroplc receptors. We found that the peptides GRP and VIP also affect SON in vivo with a pattern of temporal sensitivity similar to that of light. We studied how serotonin and melatonin alter photic responses of SON cells, and showed that serotonin acts via a receptor that resembles the 5-HT7 subtype. We recently demonstrated differences in the responses to light of SON neurons in nocturnal rodents compared to those is degus, a diurnal/crepuscular rodent. In vivo and in vitro studies suggest the possibility that the inhibitory neurotransmitter GABA is found in the retinal entrainment route in both types of mammals, along with the excitatory transmitter glutamate. To facilitate our behavioral studies, we developed a data analysis system for dealing with activity rhythm data collected by computer.

The long-term goal of this study is to examine the vertical structure in bio-optical properties and to classify features that persist at large scales, particularly with a view to application in remote sensing of the underwater light field and of the water-column primary productivity at basin to global scales. In the present proposal, we emphasise issues related to the vertical structure of the water column: (1) the use of coupled models to improve our understanding of the vertical structure of the water column, and (2) the use of information other than just chlorophyll-a to refine optical models. The work will be oriented towards examining the implications of vertical structure for penetration of light underwater and for remote sensing of primary production., See also ADM002252. Prepared in cooperation with Bedford Institute of Oceanography, Dartmouth, Nova Scotia.

The central goal of this project is a deeper understanding of the dynamic adjustment of mobile sandy sediments to fluid forcing in the surf zone at small (1cm to 10m) and intermediate (10cm to 100m) horizontal scales. The effort is motivated by the dual need to develop more realistic models of fluid-sediment interactions in the nearshore zone, and for suitable in situ measurement techniques to make the observations necessary to adequately test the models. Of particular interest is the role of bedforms of different characteristic spatial pattern and scale in the local sediment flux and momentum balances. The overall objective of this project is to study bedform genesis, growth, migration, and decay, together with the associated fluid forcing and sediment suspension, in the natural surf zone. A key initial objective was to obtain a comprehensive set of measurements of bed adjustment through time, as a function of cross-shore position, and over a period of several months. This data set will provide a basis for determining cross-shore differences in response synoptically, and for differences in the response trajectories through time and between forcing events, over a suitably wide range of conditions., See also ADM002252.

The long-term goal of this research is to use remotely sensed ocean optical data for estimates of the regional and global scale significance of photochemistry to dissolved organic carbon (DOC) cycles and optical changes resulting from these processes. The central objective of this research program is to examine quantitatively the links between optical measurements and photochemical carbon transformations in the sea. Our goal is to establish quantitative methods to relate variability in water-leaving radiance to photochemical reactions that lead to direct loss of colored dissolved organic matter (CDOM) and consequent changes in UV optical properties in the photic zone. By examining these quantitative relationships, we also hope to gain both an understanding of the dominant variables controlling UV optics in the mixed layer and the critical parameters influencing DOC photochemical reactions in seawater., See also ADM002252.

The long-term goal of this research is to develop tools to quantitatively predict the effect of fine siliciclastics on water clarity in the coastal ocean. Scattering of light by suspended particles depends on sediment concentration, composition, and size distribution. Particle size distributions in coastal waters are dynamic because high concentrations of suspended sediment in coastal waters favor frequent encounter between particles. These encounters lead to the formation of large macroaggregate particles, or flocs, with diameters greater than 0.5 mm. While aggregation modifies the size distribution by building larger particles, variable and energetic turbulence in coastal waters can modify the size distribution by disrupting aggregates. Predictive knowledge of scattering depends on understanding of the conditions under which aggregation and turbulence-induced disaggregation alter the size distribution and of the form of the size distribution that these processes combine to produce. OBJECTIVES This research has three primary objectives. The first is to observe spatial and temporal variability in macroaggregate size distributions in situ in the bottom boundary layer (BBL) at the Coastal Mixing and Optics field site. The second is to relate observed size distributions to small particle size distributions, turbulent kinetic energy (tke), and optical properties in the BBL. The third is to extend BBL aggregation models to conditions of unsteady flow., See also ADM002252.

The long-term goals of this research are to develop and test a particle aggregation parameterization in turbid, river, discharge plumes. The proposed research has two objectives. The first is to monitor the evolution of in situ and disaggregated particle size distributions in the Eel River plume during major discharge events. The second is to develop and test a simple parameterization of particle aggregation that can be incorporated directly into dynamic plume models., Prepared in collaboration with the Bedford Institute of Oceanography, Dartmouth, Nova Scotia. See also ADM002252.

This program of research identified a number of novel roles for peptides and neurotransmitters found in the suprachiasmatic nuclei (SCN), in the regulation of SCN neuronal activity and behavioral circadian rhythms. Major findings included the observations of changes in SCN cell firing rates and behavioral phase shifts induced by gastrin releasing peptide (GRP) when applied to SCN cells. GRP was demonstrated not to act primarily in concert with other peptides in a manner proposed by an earlier publication. Similar combinations of neurophysiological and behavioral studies have been completed using another peptide, substance P, and are partially completed using VIP. Other studies have investigated the neurophysiological role of metabotropic glutamate receptors, and the behavioral effects of their activation or blockade. Neurophysiological studies investigated the effects of melatonin and of serotonin on photic responses of SCN cells and evaluated putative antagonists for these effects. Antagonists that acted selective on the melatonin and serotonin receptors in the sCN were identified. Additional studies examining the neurophysiological effects of opiatergic drugs, histamine and redox agents were also completed.