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Plasma environments constitute powerful tools in materials science due to their operation as thermal and chemical reactors. A microwave, atmospheric argon plasma driven by surface waves has been used for synthesizing carbon nanostructures by passing vaporized ethanol through the plasma. Graphene sheets and carbon nanoparticles have been selectively synthesized through the control of the outlet plasma stream temperature., See also ADA594770. International Conference on Phenomena in Ionized Gases (31st) (ICPIG) Held in Granada, Spain on 14-19 July 2013

Since 2003, the Portuguese Ministry of Defense (MoD) has been using the MACBETH multicriteria approach in several evaluation processes for the acquisition of military equipment. This paper describes the first application case: the acquisition of 8x8 Armored Wheeled Vehicles to equip the Army and the Navy Marines, which contract was recently signed. This Tender was conducted by the National Armaments Directorate in cooperation with the Army and the Navy. The process last almost two years and involved: on a first stage, the revision and harmonization of the Services' requirements, and the issuing of the Tender Program and of the Technical Specifications; the process proceeded with the initial proposals' analysis, the performance of tests in Portugal and abroad, and the negotiation meetings; the final stage of the Tender comprehended the admission and evaluation of the Best and Final Offers, and finally the award of the contract to the globally most attractive proposal. Tender's Evaluation Regulation was based on the MACBETH (Measuring Attractiveness by a Categorical Based Evaluation Technique) methodology, previously adopted on large national and international tender procedures, that proved to be a flexible, consistent and robust decision support tool., See also ADA562565. RTO-MP-SAS-080 Decision Support Methodologies for Acquisition of Military Equipment (Methodologies d'aide a la decision pour l'acquisition d' equipements militaires). Meeting Proceedings of Systems Analysis and Studies Panel (SAS) Specialists Meeting held in Brussels, Belgium on 22 and 23 October 2009., The original document contains color images.

In this paper, we analyse the radiation on a step discontinuity of a grounded chiral slab, and we show that it can be enhanced due to the effect of chirality. In addition to the surface modes, the continuous spectrum of radiation modes is also taken into account. In fact, it is the coupling between these two types of modes that is responsible for the radiation occurring on the step. We show that chirality may increase such coupling and, therefore, improve radiation. The complete spectral representation includes two subsets of continuous hybrid modes: Incident Transverse Electric (ITE) and Incident Transverse Magnetic (ITM) radiation modes. The scattering matrix of the step is determined by minimizing the boundary residual error in the sense of the least squares. The influence of chirality on the characterization of the step is demonstrated and we show that some control on the radiation pattern is achieved, mainly in the angle and width of the radiation beam., Presented at Intl. Conference on Electromagnetics of Complex Media (8th), Lisbon, PT, 27-29 Sep 2000, p325-328. This article is from ADA398724 International Conference on Electromagnetics of Complex Media (8th), Held in Lisbon, Portugal on 27-29 September 2000. Bianisotropics 2000

This paper presents results of two-dimensional LDA measurements performed in the near wake of an airfoil undergoing stepwise motions and saw-tooth periodic motions with incidence variations from -1 deg to 25 deg, revealing dynamic stall features. The driving mechanism used here is a new one, based on an automatic apparatus, which allows the airfoil to be put into a wide range of periodic or transient pitching and/or heaving motions. Time-dependent velocity traces for the two components, streamwise velocity profiles, evolution of the semi wake thickness and vector velocity field are discussed. These results, obtained at a Reynolds number of 267000, are compared to those corresponding to steady flow. (Author)

In this paper, we will be dealing with the quality of the air/fuel mixture, in particular its dependence upon injection timing regarding the valve opening law, injector position and orientation within the manifold. Valve movement spray interaction is obtained from this experimental study. (Author)

A new type of anemometer based on low coherence interferometry is examined, In the proposed scheme, a fluctuation of an interference output formed with a light component scattered at a chosen depth in a fluid is detected and is fourier-processed. Consequently, a distributed sensing of the flow velocity along the depth can be achieved. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p14.5.1-14.5.4.

A Laser Doppler Velocimetry was developed to measure the full-scale propeller inflow distribution as a basis of calculating propeller vibratory forces. The present development is featured by (1) wide range of measurement as far as 8m away from the hull and (2) improving signal to noise ratio to measure the long distance within a relatively short period of measurement. In this paper is presented the description of this measurement system, together with some results of full-scale measurement and discussion on them., This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p16.6.1-16.6.5.

Diesel fuel spray from a single hole injection nozzle was investigated under steady-state and atmospheric conditions to understand the characteristics of unsteady Diesel spray. Spray velocity and particle diameter were measured by a laser Doppler anemometer (LDA) and a phase Doppler anemometer (PDA) respectively. Distributions of mean velocity and fluctuation (turbulence) characteristics in the spray flow were analyzed and compared with gas jets and other experiments. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p37.5.1-37.5.6.

Laser-Doppler measurements of the mean and turbulent velocity characteristics of coaxial jets stabilized downstream of a model prefilming airblast atomizer with a conical shape are presented and discussed together with visualization of the flow. The results include the analysis of the effect of swirling the outer jet on the mixing performance of the injector and consider the use of two different swirl generators. Flat vanes upstream of the present conical nozzle promotes the instability and rolling up of the shear layer and leads to some asymmetric flow with a spiral pattern associated with increased turbulence levels far downstream of the nozzle exit. The use of a swirl chamber with tangential slots gives rise to the occurrence of a recirculation zone in the vicinity of the nozzle, which is penetrated by the inner jet and is associated with increased turbulence levels. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p17.1.1-17.1.8.

The application of high-frequency pulsed diode lasers in a two-component backscattering laser Doppler anemometer is explored. Basically, each component is a standard fringe type dual beam LDA, but instead of operating the lasers in cw-mode, a high frequency pulse-mode is used. The benefits are a multi-component measuring technique using the same wavelength, a multiple energy-density in the measuring volume at time of interest and a single receiving system and data acquisition system. Aspects on pulsing the diodes, optical wavelength spectra as well as the receiving system and electronic data reduction methods will be outlined. (Author) Experimental results of a two component pulsed LDA will be presented. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p11.2.1-11.2.5.

This paper is devoted to the description of the interaction between a spherical particle and a laser sheet beam (Gaussian beam focussed by a cylindrical lens) by using the generalized Lorenz-Mie theory (GLMT). Comparisons between the scattering properties of laser sheet, Gaussian beam, and plane wave are carried out. (Author)

Traditionally, the P. T. V techniques use a camera to record the displacement of the particles. Then, it is necessary to develop the negative film in order to digitize the images. In this paper, we present a now P.T.V method which is based on colored pulses and a color video camera (3 CCD camera). The particles images are digitizing in real time with a resolution of 24 bits and an image processing software allows to obtain the velocities field. After describing the experimental procedure, some results are presented on a water sock-up. (Author)

A fiber-optic laser-Doppler anemometer microscope (FLDAM) was developed to measure the red cell velocity in microvessels with diameters ranging from 5 micrometers to 100 micrometers. The temporal resolution of the FLDAM is sufficiently high to measure the pulsatile velocity in microlevels synchronous with the heart beat. The FDLAM also exhibits sufficient spatial resolution to obtain the velocity distribution in microvessels. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p4.5.1-4.5.6.

The velocity field generated by thermal convection in a model porous medium is experimentally determined by means of both PIV and LDA techniques. Details of matching refraction index under non isothermal conditions and some preliminary results are given. (Author)

The experimental aerodynamic characterization of a coaxial jet through LDA and hot-wire measurements is described. It is shown that, in the flow regions where the local level of turbulence is not excessive, the two techniques give similar results as regards the mean velocity and the statistical description of the turbulent components. Conversely, the time variations and spectra may be comparable only if adequate procedures are used for the acquisition and processing of the LDA signals. (Author)

The combustion in a turboreactor generates submicronic solid particles. In order to determine the size repartition of these unburned particles we realised an prototype which uses a laser radiation scattering. The system was tested on supersonic flows., This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p18.1.1-18.1.4.

Using diffraction gratings as beam splitters in LDA systems the resulting fringe spacing becomes achromatic. Thus employing unstabilized laser diodes of different wavelengths, distinguishable fringe systems with identical fringe spacings int he measuring volume can be generated. The evaluation of at least two LDA burst signals and their signal phase corresponding to the different fringe systems locally parallel shifted and/or tilted against each other allows the directional measurement of lateral and axial velocity components without using frequency shift techniques. Based upon the new techniques inexpensive and compact multicomponent LDA sensors for the directional measurement of lateral and axial velocity components can be realized. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p2.1.1-2.1.5.

Fuel droplet velocity and size measurements have been obtained in a combusting Diesel spray inside a single-cylinder direct injection Diesel engine. The measurements were made in the near nozzle region by phase Doppler anemometry with high spatial and temporal resolution. An analysis of the data describes the fuel spray breakup and atomization based on a liquid jet and model and identifies three distinct zones in the developing spray. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p25.1.1-25.1.7.

LDV measurements of the mean and turbulent velocity characteristics are presented for turbulent flow over a cavity. Three different shapes for the impingement cavity edge, sharp, round and nose, were employed. The reported measurements covered two particular regimes: low Reynolds number flow (Re sub b = 2400 x 10 3) fully turbulent flow (Re sub = 48000 x 10 4). The former regime displayed self-sustained flow oscillations but, in the latter regime, organized oscillations were not observed. The investigated geometries did not change neither the Strouhal number nor the flow structure immediately after the cavity. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p7.2.1-7.2.6.

The purpose of this work was to investigate the possible advantages of continuously traversing an LDV to obtain velocity profiles in unsteady pipe flows. Two cases were considered, the successful and efficient measurement of which has supported the soundness of the method: an impulsively started pipe flow showing the evolution from 'top hat' to parabolic velocity profiles, and the occurrence of transition in the same type of flow subjected to finite disturbances. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p2.3.1-2.3.4.

The application of a PIV system to a flotation apparatus is described. The aim of the experiments is to explore the general flow pattern in the cell and to measure the velocities and the distribution of the solid and gaseous phases. Preliminary results on the flow in the cell as caused by the through flowing fluids end by the stirrer system are presented. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p9.4.1-9.4.4.

Particle image velocimetry (PIV) is used for measuring the velocity of suspended solid and gaseous particles in the model of a three phase reactor. The mean size of the solid and the gaseous particles (bubbles) differes by more than one order in magnitude. The measuring system can distinguish between small and big particles, and it can therefore provide information ont he concentration of the solid and the gaseous phase. The ambiguity in the sign of the measured velocity vectors is resolved by moving, the recording camera at constant speed. Regimes of recirculating flow are visualized by a chemical time reaction. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p9.1.1-9.1.3.

The use of a laser-Doppler velocimeter has been extended to the analysis of turbulent heat transfer in a strongly sheared disc-stabilized propane-air flame through its combination with either laser Rayleigh scattering or digitally-compensated fine-wire thermocouples. The laser velocimeter was based on a conventional forward scattering system from the green light of a 5W Argon-Ion gas laser, while the Rayleigh signals used the blue line of the same laser. The procedure for the numeric compensation of the thermocouple signals included analysis of the effect of velocity and temperature on the time constant of the thermocouple and was optimized to allow combined velocity-temperature samples acquired by a purpose-built digital interface with a frequency up to 2000 Hz without deterioration of the thermocouple by particle accretion. The maximum effective data rate for the combined Rayleigh/LDV system is shown to be around 130 Hz, which corresponds to a data rae of valid Doppler signals around 400 Hz. The results obtained with the two systems agree qualitatively, although the use of thermocouples attenuates the measured velocity-temperature correlations. The results are used to assess the extent to which turbulent mixing in flames is altered by the accompanying heat release and quantify the processes of non-gradient diffusion in a strongly recirculating premixed flame., This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p34.1.1-34.1.9.

This report presents an utilization of laser measurement technique in the specific domain of sodium aerosols. More especially aerosols velocities and sizes were studied using Laser Doppler Velocimetry and Phase Doppler method. The difficulties encountered and synthesis of the experimental results obtained are detailed.

A water-cooled jacket enclosing a small fiber-optics LDA probe has been designed to perform laser velocimetry measurements in semi-industrial scale flames. The paper presents details of the probe design for front optics cooling and prevention of window contamination. Experiments in natural gas, heavy fuel oil and coal flames have demonstrated fast and reliable operation. Laser velocimetry measurements are performed with the same speed as standard suction pyrometry. Operation for long periods in high temperature flames with high particle loading showed no heating of the LDV optics and no fouling of the front window. The effects of the probe intrusiveness and probe purge flow on the measurements accuracy were assessed and shown to be minor, provided that the measurement volume is located at least one and a half probe diameter from the probe tip. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p22.3.1-22.3.6.

A laser-Doppler velocimeter has been used to quantify the velocity characteristics of an unconfined recirculating flame with an heat load around 150 kW formed downstream of an annular jet propane gas surrounded by a co-axial swirling air flow, which was set at Re = 58000. The results characterize the aerodynamics of disc-stabilized non-premixed flames within a swirling air flow and include the analysis of the rate of heat transfer in these flames. To achieve these objectives, the laser velocimeter was combined with digitally-compensated fine-wire thermocouples, which have also allowed to quantify the extent of the degree of internal mixing obtained in annular swirling flames. The results were obtained for fuel-lean conditions (AFR = 44.7) and identify an annular swirling flow associated with a double vortical structure established in the wake of the baffle with maximum negative velocities around 0.20 U sub 9 at r/D sub 9 = 0.45 and positive centerline velocities up to +0.1 U sub 9. The diffussion of heat in the radial direction is shown to follow conventional scalar-viscosity concepts, but there are large zones of the reacting shear layer where the results show axial counter-gradient diffusion of heat

The paper describes the improvements int he enhanced Burst Spectrum Analyzer. Besides a general description of the improvements, the paper contains results from measurements close to solid surfaces, where the present burst detection principle is compared to the burst detector previously used. (Author), This article is from 'International Symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements (6th) Held in Lisbon, Portugal on July 20-23, 1992', AD-A258 510, p21.2.1-21.2.4.

This volume contains the papers to be presented at the Sixth International symposium on Applications of Laser Techniques to Fluid Mechanics and Workshop on Computers in Flow Measurements held in Lisbon, in the period July 20-23, 1992. the aim of the Symposium is to provide a forum for the presentation of new research o laser techniques for flow measurements and results of significance to fluid mechanics. The application of laser techniques to scientific and engineering investigations of fluid flow is emphasized, but contributions to the theory and practice of laser methods are considered where they facilitate new improved fluid mechanic investigations. Attention is focused on laser-Doppler anemometry, particle sizing and other methods for the measurement of velocity and scalars, such as particle image velocimetry and laser induced fluorescence., For sales information of individual items, see AD-P008 901 thru AD-P009 059.

This volume features contributions by forerunners in the fields of solid-state ionics and battery technology, from universities, research organizations and industry. In providing a balance between a thorough state-of-the-art review and broadly-based insights into likely future developments in the field, the volume covers the following subjects: a review of the fundamental materials' and experimental aspects of solid-state electro-chemistry; an introduction to and review of battery technology, and detailed accounts of solid-state systems. These include descriptions of battery performance, fabrication techniques and applications. Also provided is a review of related technologies, including solid-state sensors. The publication will be of primary interest to workers in the fields of solid state electro-chemistry, battery science and technology, and ionically-conducting materials.

A mathematical programming formulation is presented for the elastic synthesis of truss structures with specified topographic and mechanical properties, undergoing finite displacements. The description for Statics and kinematics, valid for arbitrarily large displacements and deformations, is expressed in either mesh or nodal formats, according to the connectivity properties of the fundamental substructures selected to describe the assembled structure., This article is from Proceedings of the International Symposium on Optimum Structural Design, AD-A119 989.