WorldWideScience

Sample records for armour

  1. Fatigue of Concrete Armour Units

    DEFF Research Database (Denmark)

    Sørensen, N. B.; Burcharth, H. F.; Liu, Z.

    1995-01-01

    In the present article fatigue as a possible reason for failure of Dolosse armour units made of plain concrete is discussed.......In the present article fatigue as a possible reason for failure of Dolosse armour units made of plain concrete is discussed....

  2. UNDER ARMOUR DOMINA

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    随着足球鞋种类的细分,以ADIDAS PREDATOR、NIKE TOTAL90、PUMA V-KONSTRUCT为代表的力量、功能型球鞋得到了很多球员的喜爱。UNDER ARMOUR DOMINATE PR0也是这种类型的球鞋。不过同样是偏重力量的足球鞋,UNDER ARMOUR却另辟蹊径。

  3. Structural ballistic armour for transport aircraft

    OpenAIRE

    Horsfall, I; Austin, S J; Bishop, W.

    2000-01-01

    This paper describes the structural response of a current ceramic-faced composite armour system and a proposed structural armour system for aircraft use. The proposed structural ballistic armour system is shown to be capable of providing significant structural integrity even after ballistic impact whilst providing ballistic protection equivalent to an existing applique system. The addition of a carbon fibre reinforced plastic front panel to the existing ceramic faced composite armour system i...

  4. Hydraulic Stability of Accropode Armour

    DEFF Research Database (Denmark)

    Jensen, T.; Burcharth, H. F.; Frigaard, Peter

    The present report describes the hydraulic model tests of Accropode armour layers carried out at the Hydraulics Laboratory at Aalborg University from November 1995 through March 1996. The objective of the model tests was to investigate the hydraulic stability of Accropode armour layers......, and to assess the influence of core permeability on the hydraulic stability of Accropodes. Two structures were examined, one with a relatively permeable core and one with a relatively impermeable core. In November/December 1995, Ph.D.-student Marten Christensen carried out the model tests on the structure...... with permeable core (crushed granite with a gradation of 5-8 mm). The outcome of this study is described in "Hydraulic Stability of Single-Layer Dolos and Accropode Armour Layers" by Christensen & Burcharth (1995). In January/February 1996, Research Assistant Thomas Jensen carried out a similar study...

  5. Spatial Damage Distribution over Cube Armoured Roundheads

    DEFF Research Database (Denmark)

    Alonso, Enrique Maciñeira; Burcharth, Hans F.

    2009-01-01

    Different authors have studied and defined the most critical sector of the roundheads with respect to armour stability in order to calculate the mass needed in the units of the armour. This sector has been located between 90° and 135° relative to the orthogonal of the waves. Moreover, from these ...

  6. Future Armoured Troop Carrying Vehicles

    Directory of Open Access Journals (Sweden)

    Sebastian Balos

    2010-08-01

    Full Text Available Present-day reliance on wheeled and tracked armour personnel carriers (APCs and infantry fighting vehicles (IFVs, may be changed in the future. Shaped charge grenades and impovised explosive devices (IEDsrepresent a considerable threat, even to well protected main battle tanks (MBTs. Paradoxically, the crew of wheeled and tracked troop-carrying vehicles is numerically three to four times larger than that of MBTs, however, their protection in all aspects is significantly lower. Therefore, heavier vehicles may get more attention in the future, where sharing the chassis and a number of components with MBTs could provide significant reductions in procurement costs and maintenance, as well as a simplified logistics in relation to the latest tracked. Obviously, the IFVs mobility of heavy vehicles would be lower than that of lighter vehicles. However, by applying various degrees of modular armour protection, a significant rise in strategic, operational, and tactical mobility could be achieved. Such heavy tracked vehicles, built on a common chassis as MBTs, may equip the future heavy brigades, which will be in contrast to the lighter wheeled vehicles included in rapid deployment brigades. As a result, tracked personnel carrying vehicles may extinct in the future.Defence Science Journal, 2010, 60(5, pp.483-490, DOI:http://dx.doi.org/10.14429/dsj.60.550

  7. Fatigue in Breakwater Concrete Armour Units

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    1985-01-01

    The reliability of rubble mound breakwaters depends on the hydraulic stability and the mechanical strength of the armour units. The paper deals with the important aspect of fatigue related to the strength of concrete armour units. Results showing significant fatigue from impact tests with Dolosse...... made of unreinforced and steel fibre reinforced flyash concrete are presented. Moreover universal graphs for fatigue in armour units made of conventional unreinforced concrete exposed to impact load and pulsating load are presented. The effect of fibre reinforcement and the implementation of fatigue in...

  8. Stresses in Dolos Breakwater Armour Units

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Z.

    1991-01-01

    Breakage of slender unreinforced armour unite is the cause of many breakwater failures. Design diagrams to ensure structural integrity of armour unite such as dolosse and tetrapods have not been available. The article presents results of an analysis of the stresses in dolosse based on model tests...... with load-cell instrumented dolosse with masses of 200 kg and 200 g. A preliminary design diagram is presented as well....

  9. Losses in armoured three-phase submarine cables

    DEFF Research Database (Denmark)

    Ebdrup, Thomas; Silva, Filipe Miguel Faria da; Bak, Claus Leth;

    2014-01-01

    The number of offshore wind farms will keep increasing in the future as a part of the shift towards a CO2 free energy production. The energy harvested from the wind farm must be brought to shore, which is often done by using a three-phase armoured submarine power cable. The use of an armour...... increases the losses in armoured cables compared to unarmoured cables. In this paper a thorough state of the art analysis is conducted on armour losses in three-phase armoured submarine power cables. The analysis shows that the IEC 60287-1-1 standard overestimates the armour losses which lead to the...

  10. Stability of Armour Units in Oscillatory Flow

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Thompson, A. C.

    1983-01-01

    As part of a program to study the hydraulics of wave attack on rubble mound breakwaters tests were made on model armour units in a steady flow through a layer laid on a slope. The flow angle has little effect on stability for dolosse or rock layers. The head drop at failure across each type of la...

  11. Stability of Armour Units in Oscillatory Flow

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Thompson, A. C.

    Despite numerous breakwater model tests very little is known today about the various phenomena and parameters that determine the hydraulic stability characteristics of different types of armour. This is because separation of parameters is extremely difficult in traditional tests.With the object of...

  12. New Formula for Stability of Cube Armoured Roundheads

    DEFF Research Database (Denmark)

    Maciñeira, Enrique; Burcharth, Hans F.

    2007-01-01

    Design of armour for rubble mound breakwater roundheads constitutes in many cases a problem due to the limitation of available data and guidelines. The objective of the paper is to present the results of a comprehensive model test study on the stability of cube armoured roundheads, resulting in a...... new stability formula...

  13. Influence of Core Permeability on Accropode Armour Layer Stability

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Christensen, M.; Jensen, T.;

    1998-01-01

    Hedar and van der Meer studied the influence of core permeability on the stability of two layer rock armour. In both cases a significant influence was found. However, it is to be expected that for single layer armour there will be an even larger influence on the core permeability. This is because...

  14. Stability of Cubipod Armoured Roundheads in Short Crested Waves

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke; Medina, Josep R.

    2011-01-01

    The paper presents a comparison of the stability of concrete cube armour and Cubipod armour in a breakwater roundhead with slope 1:1.5, exposed to both 2-D (long-crested) and 3-D (short-crested) waves. The model tests were performed at the Hydraulics and Coastal Engineering Laboratory at Aalborg ...

  15. Thermal effects of runaway electrons in an armoured divertor

    International Nuclear Information System (INIS)

    This report describes the results of a numerical thermal analysis of the heat deposition of runaway electrons accompanying plasma disruptions in a armoured divertor. The divertor concepts studied are carbon on molybdenum and beryllium on copper. The conclusion is that the runaway electrons can cause melting of the armour as well as melting of the structure and can damage the divertor severely. (orig.)

  16. Armour Protection and Affordable Protection for Futuristic Combat Vehicles

    Directory of Open Access Journals (Sweden)

    V. Madhu

    2011-07-01

    Full Text Available Protection creates a shift in the internal paradigm of the soldier and leads to multiplied psychological stamina for moving fearlessly in the battlefield which generates a major force-multiplier effect. Hence, the mechanized forces are still likely to be one of the dominant forces on the futuristic battlefield and would be the primary target of enemy forces capable of engaging from tank guns up to 4-5 km in a direct fire mode and up to 8-10 km in an indirect fire modes. Increased protection is possible only using advanced armour technology. Throughout the history of warfare, materials technologies have had a significant impact on land-combat force capabilities. Armour materials have progressed through improvements in metallic systems and development of advanced, lightweight (low areal density composite materials. The advancements in ceramic systems have further improved the performance. Similarly, the advances in development of explosive reactive armour has generated efficient armour system against all contemporary high explosive antitank (HEAT ammunition and missile threats for armoured vehicles. Yet, to achieve armour performance exceeding that of the current light combat vehicles and main battle tanks for new vehicular systems, weighing significantly less than the present combat vehicles, advances in new armour materials, systems, and survivability technologies are required. This paper describes various approaches and advancements in the metallic, ceramic, and composite armour materials and new dynamic armour systems that are essential to improve the survivability of armoured vehicles in the futurisitic multi-spectral battlefied scenarios.Defence Science Journal, 2011, 61(4, pp.394-402, DOI:http://dx.doi.org/10.14429/dsj.61.365

  17. Study on Basic Mechanism of Reactive Armour

    Directory of Open Access Journals (Sweden)

    H. S. Yadav

    1995-07-01

    Full Text Available Two basic mechanisms which operate in the functioning of reactive armour are presented. Both the explosive effect and cutting of metal plates by a jet have been investigated. The angle of attack and the confinement of the explosive have been found most significant factors in reducing the penetrating power of the jet. The effect of detonating explosives has been investigated with radiography. Some of the significant effects, like detonation of explosive by the impact of the jet, expansion of covering plates, disturbance in coherence and reduction in the penetration of the jet have been observed. It is found that the jet penetration in a stack of mild steel plates is reduced to 30 per cent of its blank penetration in present set-ups. A theoretical model has been conceived to study the interaction of moving plates and the jet. The critical thickness and surface cut in plates have been calculated.

  18. A Design Method for Impact-Loaded Slender Armour Units

    OpenAIRE

    Burcharth, Hans F.

    1981-01-01

    It is well known that the bigger a structural member like a beam, the relatively weaker it is. In the end it cannot even support its own weight. The same problem holds for slender armour units such as Dolosse.

  19. A Design Method for Impact-Loaded Slender Armour Units

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    It is well known that the bigger a structural member like a beam, the relatively weaker it is. In the end it cannot even support its own weight. The same problem holds for slender armour units such as Dolosse....

  20. The Evolution of Splint Armour in Georgia and Byzantium: Lamellar and Scale Armour in the 10th-12th Centuries

    Directory of Open Access Journals (Sweden)

    Mamuka TSURTSUMIA

    2011-10-01

    Full Text Available Byzantine technology was part of the military technology that existed in vast areas of Eurasia; hence study of the armament of its neighbours is important.The purpose of the present paper is to add new data about Byzantium’s Caucasian neighbour (namely, Georgia. Besides that, it also includes certain views about the stages of the evolution and provenance of splint (scale and lamellar armour. This paper also attempts to clarify the difference between banded and linear suits of lamellar armour.There is no doubt that the Byzantine military machine exercised considerable influence on its neighbours, though an opposite phenomenon can also be noticed. The article shows that changes in armour were taking place almost simultaneously in the Byzantine Empire and the Georgian kingdoms and that some of the types of armour that were widespread in Byzantium may have originated in Georgia.

  1. Computer Simulation of an Armoured Battalion Swarming

    Directory of Open Access Journals (Sweden)

    Radomir Jankovic

    2011-01-01

    Full Text Available Swarming is a tactical approach considered in modern armies combat activities conceptualisation. More intensive research of military application of swarming began after 2000, mostly in the areas of unmanned air, underwater, and ground vehicles, as well as in air force, navy and some special ground force units. In spite of relative inconveniences of contemporary main battle tanks to act as swarmers, some of initial results of the armoured mobile platforms swarming research have been presented. The motivation for the research is that adaptation of contemporary tanks for swarming could prolong their working life until the new generation comes, and could be the best investment in medium and smaller countries armies' modernisation. Brief survey of the till date research, description of the simulation model and the results of experiments simulating swarming of the battalion-sized group of armed mobile platforms, defending territory from superior adversary unit, have been considered in the paper.Defence Science Journal, 2011, 61(1, pp.36-43, DOI:http://dx.doi.org/10.14429/dsj.61.49

  2. Ultrasonic Imaging of Ballistically Impacted Composite Armour

    Directory of Open Access Journals (Sweden)

    S.S. Samant

    2013-12-01

    Full Text Available The ability of Kevlar-Polypropylene composite armour to withstand the impact of projectile (calibre 7.62 mm is investigated using immersion type ultrasonic c- scan method. The Kevlar polypropylene composite laminate is made of 36 Kevlar and 74 polypropylene layers having thickness 20 mm and are subjected to bullet impact with different striking velocities. At each location of the probe ultrasonic features peak amplitude and signal amplitude are extracted from digitized data and stored in controlling PC. Using UPGMA clustering technique, c-scan images of impacted zones of Kevlar polypropylene composite plate has been generated. The extent of core damage zone in the laminates correlated to the impact velocities of projectile. It is observed that areas of core damage zone are found to increase with the energy loss of the bullet. The area of core damage zone increases rapidly in case of shot lodging. Also peak amplitude and signal energy features are more reliable and sensitive for evaluation of damage in composite laminates.

  3. Tissue simulant response at projectile impact on flexible fabric armour systems

    NARCIS (Netherlands)

    Bree, J.L.M.J. van; Volker, A.; Heiden, N. van der

    2006-01-01

    Behind Armour Blunt Trauma is a phenomenon which has been studied extensively for rigid personal protective armour systems. These systems used in e.g. bullet proof vests manage to defeat high velocity small arms projectiles. Tissue simulants are used to study behind armour effects. At high velocity

  4. Pressure-induced forces and shear stresses on rubble mound breakwater armour layers in regular waves

    DEFF Research Database (Denmark)

    Jensen, Bjarne; Christensen, Erik Damgaard; Sumer, B. Mutlu

    2014-01-01

    measurements in the core material: (1) core material with an idealized armour layer made out of spherical objects that also allowed for detailed velocity measurements between and above the armour, and (2) core material with real rock armour stones. The same core material was applied through the entire...

  5. New Formula for Stability of Cube Armoured Roundheads

    DEFF Research Database (Denmark)

    Maciñeira, Enrique; Burcharth, Hans F.

    2009-01-01

    The paper presents a new formula for the stability of cube armoured roundheads. The formula is based on physical model tests in Aalborg University which both long crested and short crested waves of different wave steepness were used. The slope of the radius of the head were varied in order to...... explore the influence of the geometry on the armour stability. Besides cubes with mass density 2.4 t/m3, cubes with mass density 2.80 t/m3 were used in order to include the effect of mass density in the formula. The damage predictions given by the formula have been compared with prototype hand...

  6. BERM BREAKWATERS WITH CONCRETE BLOCKS AS ARMOUR UNITS

    OpenAIRE

    Camara Aguilera, Altea

    2013-01-01

    The objective of this thesis is to test the hydraulic stability of berm breakwaters with concrete armour units. To achieve this, five breakwater models were tested with the same wave program. All the models were modifications of the Sirevåg berm breakwater. The modifications consisted in the replacement of the class I stone form the armour layer by two different concrete units, cubes and cubipodsThe design waves were Hs,100=7.0 m, Tz=10.6 s. HoTo=48. The wave program consisted in 7 diffe...

  7. Structural Integrity and Hydraulic Stability of Dolos Armour Layers

    DEFF Research Database (Denmark)

    Burcharth, H. F.

    A method for development of design diagrams to ensure structural integrity of slender unreinforced concrete breakwater armour units is presented. The method is based on experimental data from small scale flume tests as well as impact loading of prototype and small scale units. A prerequisite for ...

  8. Stability of Armour Units in Flow Through a Layer

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; C. Thompson, Alex

    1984-01-01

    As part of a program to study the hydraulics of wave attack on rubble mound breakwaters tests were made on model armour units in a steady flow through a layer laid on a slope. The flow angle has little effect on stability for dolosse or rock layers. The head drop at failure across each type of...

  9. An Alternative Stability Equation For Rock Armoured Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Hald, Tue; Burcharth, H. F.

    straight forward to assume, that a relation between the exerted wave loads and the stability of the armour layer would be of major interest, but the normal approach to the problem has simply been to relate easy accessible wave parameters, e.g. wave height and period, directly to the single unit weight....... Taking a closer look on the stability formulae large differences in the influence of the different parameters are observed although several points of resemblance are observed. Despite the major efforts in obtaining a reliable stability equation a large scatter between damage predicted by the stability......Rubble mound breakwaters are by far the most common type of breakwater, the importance of which is clearly reflected in the vast amount of published research. Especially, the hydraulic stability of the main armour layer has been studied in order to obtain reliable design equations. It should be...

  10. Hypervelocity impact of tungsten cubes on spaced armour

    International Nuclear Information System (INIS)

    The paper summarizes the experimental observations and simulation studies of damage potential of tungsten alloy cubes on relatively thin mild steel spaced armour target plates in the velocity regime 1300 – 4000 ms−1 using Two Stage Light Gas Gun technique. The cubes of size 9.5 mm and 12 mm having mass 15 g and 30 g respectively were made to impact normally on three target plates of size 300 mm × 300 mm of thickness 4, 4 and 10 mm at 100 mm distance apart. Flash radiography has been used to image the projectile-target interaction in the nitrogen environment at 300 mbar vacuum at room temperature. The results reveal clear perforation by 9.5 mm cube in all the three target plates up to impact velocity of about 2000 m/s. While 12 mm cube can perforate the spaced armour upto impact velocity of 4000 m/s. This shows that 9.5mm tungsten alloy cube is not effective beyond 2000 m/s while 12 mm tungsten alloy cube can defeat the spaced armour upto 4000 m/s. The simulation studies have been carried out using Autodyn 3D nonlinear code using Lagrange solver at velocities 1200 – 4000 m/s. The simulation results are in good agreement with the experimental findings.

  11. Investigations on a brass armour: Authentic or forgery?

    International Nuclear Information System (INIS)

    A copper-based armour, supposedly excavated in Eastern Georgia and tentatively dated to the I–II century AD, was investigated with the aim of checking its authenticity. The finding consisted of several pieces, mostly in a good state of conservation: helmet, lorica musculata (i.e. muscled cuirass), forearm guards, pterygies (covering the lower body and thighs), shin greaves and a spear tip. The combination of conventional metallography with in situ and non-destructive investigations (including Time of Flight Neutron Diffraction (ToF-ND)) on the front of the lorica, on one of the pterygies and on the spear tip showed that the composition and microstructure of the armour was not fully homogeneous. However, the results from the muscled cuirass are fairly coherent and raise suspicion about the authenticity of the piece, namely because of the (i) presence of metallic Al in the alloy, in solid solution with Cu, (ii) prevalence of an as-cast microstructure, which lead to a heavy weight as well to the need for a high amount of metal by comparison to hammered sheet and (iii) presence of an artificial patina, combined with earthy deposits which are not explainable if the original patina was removed before artificial patination for aesthetical reasons. - Highlights: • Cu-based armour from Eastern Georgia (I–II century AD?): check authenticity. • Conventional metallography combined with in situ and non-destructive investigations (ToF-ND). • Suspicious points: Al in the alloy, as-cast microstructure, artificial patina

  12. Investigations on a brass armour: Authentic or forgery?

    Energy Technology Data Exchange (ETDEWEB)

    Martini, C., E-mail: carla.martini@unibo.it [Department of Industrial Engineering (DIN), University of Bologna, Via Risorgimento 4, 40136 Bologna (Italy); Chiavari, C., E-mail: cristina.chiavari@unibo.it [C.I.R.I. M.A.M (Advanced Applications in Mechanical Engineering and Materials Technology Interdepartmental Centre for Industrial Research), University of Bologna, Via Risorgimento 2, 40136 Bologna (Italy); Ospitali, F., E-mail: francesca.ospitali@unibo.it [Department of Industrial Chemistry “Toso Montanari”, University of Bologna, Viale Risorgimento 4, 40136 Bologna (Italy); Grazzi, F., E-mail: francesco.grazzi@fi.isc.cnr.it [Consiglio Nazionale delle Ricerche, Istituto dei Sistemi Complessi, Via Madonna del Piano 10, 50019 Sesto Fiorentino, FI (Italy); Scherillo, A., E-mail: antonella.scherillo@stfc.ac.uk [Consiglio Nazionale delle Ricerche, Istituto dei Sistemi Complessi, Via Madonna del Piano 10, 50019 Sesto Fiorentino, FI (Italy); Science and Technology Facility Council, ISIS Neutron Source, OX0QJ Didcot (United Kingdom); Soffritti, C., E-mail: chiara.soffritti@unife.it [TekneHub, Department of Architecture, University of Ferrara, Via Quartieri 8, 44122 Ferrara (Italy); Department of Engineering, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Garagnani, G.L., E-mail: gian.luca.garagnani@unife.it [Department of Engineering, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy)

    2013-10-01

    A copper-based armour, supposedly excavated in Eastern Georgia and tentatively dated to the I–II century AD, was investigated with the aim of checking its authenticity. The finding consisted of several pieces, mostly in a good state of conservation: helmet, lorica musculata (i.e. muscled cuirass), forearm guards, pterygies (covering the lower body and thighs), shin greaves and a spear tip. The combination of conventional metallography with in situ and non-destructive investigations (including Time of Flight Neutron Diffraction (ToF-ND)) on the front of the lorica, on one of the pterygies and on the spear tip showed that the composition and microstructure of the armour was not fully homogeneous. However, the results from the muscled cuirass are fairly coherent and raise suspicion about the authenticity of the piece, namely because of the (i) presence of metallic Al in the alloy, in solid solution with Cu, (ii) prevalence of an as-cast microstructure, which lead to a heavy weight as well to the need for a high amount of metal by comparison to hammered sheet and (iii) presence of an artificial patina, combined with earthy deposits which are not explainable if the original patina was removed before artificial patination for aesthetical reasons. - Highlights: • Cu-based armour from Eastern Georgia (I–II century AD?): check authenticity. • Conventional metallography combined with in situ and non-destructive investigations (ToF-ND). • Suspicious points: Al in the alloy, as-cast microstructure, artificial patina.

  13. Energy Absorption and Dynamic Deformation of Backing Material for Ballistic Evaluation of Body Armour

    OpenAIRE

    Debarati Bhattacharjee; Ajay Kumar; Ipsita Biswas

    2014-01-01

    The measurement of back face signature (BFS) or behind armour blunt trauma (BABT) is a critical aspect of ballistic evaluation of body armour. BFS is the impact experienced by the armour wearing body, when subjected to a non-penetrating projectile. Mineral or polymeric clay is used to measure the BFS. In addition to stopping the projectile, the body armour can be used only when the BFS also falls within permissible limits. The extent of the BFS depends upon the behavior of the backing materia...

  14. Analitical Expression of Equivalent Transverse Magnetic Permeability for three-core Wire Armoured Submarine Cables

    DEFF Research Database (Denmark)

    Viafora, Nicola; Hansen, Chris Skovgaard; Dall, Laurids Bergholdt;

    2016-01-01

    As three-core wire-armoured submarine cables become progressively more relevant, the need for refined modelling techniques grows likewise. IEC Standard 60287 indications though are still widely recognized to be insufficiently accurate, since several effects due to the presence of the collective...... wire armour are ignored. This paper therefore offers an insight into the induced losses mechanism as a function of the armour wires electromagnetic properties. The analysis is focused on the influence of the armour transverse permeability, whose overall resultant value is estimated by means of a...

  15. EXPERIMENTAL DETERMINATION OF LONGITUDINAL COMPONENT OF MAGNETIC FLUX IN FERROMAGNETIC WIRE OF SINGLE-CORE POWER CABLE ARMOUR

    Directory of Open Access Journals (Sweden)

    I.A. Kostiukov

    2014-12-01

    Full Text Available A problem of determination of effective longitudinal magnetic permeability of single core power cable armour is defined. A technique for experimental determination of longitudinal component of magnetic flux in armour spiral ferromagnetic wire is proposed.

  16. Comparison of losses in an armoured and unarmoured three phase cable

    DEFF Research Database (Denmark)

    Ebdrup, Thomas; Silva, Filipe Miguel Faria da; Bak, Claus Leth; Jensen, Christian F.

    2015-01-01

    In this article, measurements of a 245 kV 3x1x630 mm2 armoured and unarmoured cable is presented along with a description of the data processing of the measured quantities. The results of the measurements show that the losses in the armoured cable are larger than the losses in the unarmoured cabl...

  17. Evaluating the protection levels of armoured vehicles for KE, mine and IED threats

    NARCIS (Netherlands)

    Verhoeven, T.A.

    2010-01-01

    Based on providing protection to the occupants of armoured vehicles a NATO standard is under implementation (STANAG 4569). The aim of this agreement is to standardize protection levels for armoured vehicle occupants to ensure that: a. Commanders in the field can select the right equipment to fulfil

  18. Performance of carbon fiber reinforced rubber composite armour against shaped charge jet penetration

    Directory of Open Access Journals (Sweden)

    Yue Lian-yong

    2016-01-01

    Full Text Available Natural rubber is reinforced with carbon fiber; the protective performances of the carbonfiber reinforced rubber composite armour to shaped charge jet have been studied based on the depth of penetration experiments. The craters on the witness blocks, the nature rubber based composite plates’ deformation and the Scanning Electron Microscopy for the hybrid fiber reinforced rubber plate also is analyzed. The results showed that the composite armour can affect the stability of the jet and made part of the jet fracture. The carbon fiber reinforced rubber composite armour has good defence ablity especially when the nature rubber plate hybrid 15% volume percentage carbonfiber and the obliquity angle is 68°. The hybrid fiber reinforced rubber composite armour can be used as a new kind of light protective armour.

  19. User Friendly Explosives Reactive Armour a Long term Reality

    Directory of Open Access Journals (Sweden)

    S. N. Dikshit

    1997-04-01

    Full Text Available Abstract : There is a strong need to develop explosive reactive armour (ERA for protecting battle tanks against an emerging threat of kinetic and chemical energy missiles. In this context, global trends, principle and limitations of ERA and threat perception-based types of ERA have been dwelt upon. User-friendly ERA is a long-term reality. User-friendly ERA system is thus defined to be an efficient and protective system that not only provide full protection to the tank crew, but is also harmless to the supporting infantory. The indigenously-developed ERA system is close to be termed as a user-friendly ERA.

  20. Design, Performance and Fit of Fabrics for Female Body Armour

    OpenAIRE

    Yang, Dan

    2011-01-01

    This thesis focuses on the development of a new technique which enables a novel type of front panel for female body armour to be engineered, providing female contour,high level protection, and therefore comfort in wearing.The traditional cutting and stitching method can be used to form a dome shape toaccommodate the bust area but it gives rise to weakness against projectile impactat the seams.A novel type of fabric with the advantage in mouldability is needed as an alternative to the conventi...

  1. Impulsive Loading of Armour by High Explosive Squash Head Munition

    Directory of Open Access Journals (Sweden)

    P.U. Deshpande

    2003-10-01

    Full Text Available Results obtained by theoretical modelling studies involving classical stress-strain theories, duly validated by experimental investigation in understanding the mechanism of impulsive loading (scabbing and blast under dynamic and static conditions, are discussed. This concept has been used in designing a high explosive squash head ammunition being effective in defeating monolithic armour. Efforts have been made to carry out an in-depth study in understanding the mechanism of scabbing under static and dynamic (live firing conditions. For this purpose, a one-dimensional computer code has been used to predict the spread of explosive against time on the target. The simulations were carried out using a 2-D Lagrangian hydrodynamic code for scabbing effect. The blast effect that follows under static and dynamic conditions has also been studied. Blast parameters have been computed in terms of TNT equivalent and compared with experimental results. The events occurring during impulsive loading of 135 mm monolithic rolled homogenous armour have been illustrated.

  2. Material characterization of a novel new armour steel

    Directory of Open Access Journals (Sweden)

    Stumpf W.E.

    2012-08-01

    Full Text Available The material characterization of a novel new armour steel with comparison to a leading commercial benchmark alloy is presented. Direct ballistic and experimental comparison is drawn. The 5.56 × 45 mm [M193] and 7.62 × 51 mm [NATO Ball] projectiles were used in a cartridge type high pressure barrel configuration to evaluate the superior plugging resistance of the new steel over a range of plate thicknesses. To characterize the dynamic plasticity of the materials, quasi-static, notched and high temperature tensile tests as well as Split Hopkinson Pressure Bar tests in tension and compression were performed. The open source explicit solver, IMPACT (sourceforge.net is used in an ongoing numerical and sensitivity analysis of ballistic impact. A simultaneous multi variable fitting algorithm is planned to evaluate several selected numerical material models and show their relative correlation to experimental data. This study as well as micro-metallurgical investigation of adiabatic shear bands and localized deformation zones should result in new insights in to the underlying metallurgical and physical behavior of armour plate steels during ballistic perforation.

  3. The Influence of Waist Thickness of Dolosse on the Hydraulic Stability of Dolosse Armour

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Brejnegaard-Nielsen, Torben

    1987-01-01

    The paper presents results from experiments with Dolosse having the same mass and volume but with different waist thickness to height ratios. The armour was exposed to irregular waves simulating one storm with increasing wave heights and the effect of waist to height ratio on the hydraulic...... stability was studied. A low packing density of approximately 0.65 was used corresponding to a two-layer armour with high porosity. From the results it is concluded that the hydraulic stability of Dolos armour is not very sensitive to variations in the waist to height ratio. Only for damage levels exceeding...... is concluded that design criteria solely based on movements of armour units as observed in hydraulic models are not adequate for the assessment of structural integrity of the units. The paper also presents the results of each stability test as well as the scatter and the distributions. The large...

  4. Erosion simulation of first wall beryllium armour under ITER transient heat loads

    International Nuclear Information System (INIS)

    The beryllium is foreseen as plasma facing armour for the first wall in the ITER in form of Be-clad blanket modules in macrobrush design with brush size about 8-10 cm. In ITER significant heat loads during transient events (TE) are expected at the main chamber wall that may leads to the essential damage of the Be armour. The main mechanisms of metallic target damage remain surface melting and melt motion erosion, which determines the lifetime of the plasma facing components. Melting thresholds and melt layer depth of the Be armour under transient loads are estimated for different temperatures of the bulk Be and different shapes of transient loads. The melt motion damages of Be macrobrush armour caused by the tangential friction force and the Lorentz force are analyzed for bulk Be and different sizes of Be-brushes. The damage of FW under radiative loads arising during mitigated disruptions is numerically simulated.

  5. On the Determination of Concrete Armour Unit Stress including Specific Results related to Dolosse

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Howell, G.L.; Liu, Z.

    1991-01-01

    Failures of rubble mound breakwaters armoured with complex types of unreinforced concrete armour units are often due to breakage. This happens when the stresses exceed the material strength. Sufficient parametric studies of the stresses are not yet available to produce design diagrams for...... scale effects. Moreover, some results from the Crescent City Prototype Dolosse study are presented and related to results from small-de model tests. A preliminary design diagram for Dolosse ir presented as well....

  6. Ballistic Performance of Coconut Shell Powder/Twaron Fabricagainst Non-armour Piercing Projectiles

    Directory of Open Access Journals (Sweden)

    M.S. Risby

    2008-03-01

    Full Text Available Body armour technologists over the years are seeking to develop protective systems whichare both effective and lightweight. However these hard armour materials are very expensive andhave certain weight constraints. From this point of view, natural fibres and fillers have attractedthe attention of researchers due to their low density with high specific strengths, abundance,availability, renewability and being environmental-friendly. This paper reports the potential useof coconut shell powder-epoxy composite (COEX panel bonded with Twaron CT716 fabric asa hard armour material and the characteristics of its fracture imprints from a specific threat levelwhen subjected to ballistic tests1 (NIJ Standard 0108.01. It was observed that the imprint patternson the particulate composite (COEX could be identified according to effectiveness in impactenergy dissipation. COEX/Twaron test panel was found to withstand impact equivalent to NIJLevel IIIA using 9 mm FMJ ammunition but perforated at NIJ Level III of 7.62 mm FMJ bulletimpacts. Test results showed that COEX panel do possess shock absorbance characteristics andcan be utilised as  an armour component in the hard-body armour system. Dependency onTwaron fabric layers as ballistic reinforcements has been reduced up to 3-time with 170 per centimprovement on energy-absorption capabilities when using COEX composite as the frontalcomponent of the armour.

  7. Vascularised endosteal bone tissue in armoured sauropod dinosaurs

    Science.gov (United States)

    Chinsamy, Anusuya; Cerda, Ignacio; Powell, Jaime

    2016-01-01

    The presence of well-vascularised, endosteal bone in the medullary region of long bones of nonavian dinosaurs has been invoked as being homologous to medullary bone, a specialised bone tissue formed during ovulation in birds. However, similar bone tissues can result as a pathological response in modern birds and in nonavian dinosaurs, and has also been reported in an immature nonavian dinosaur. Here we report on the occurrence of well-vascularised endosteally formed bone tissue in three skeletal elements of armoured titanosaur sauropods from the Upper Cretaceous of Argentina: i) within the medullary cavity of a metatarsal, ii) inside a pneumatic cavity of a posterior caudal vertebra, iii) in intra-trabecular spaces in an osteoderm. We show that considering the criteria of location, origin (or development), and histology, these endosteally derived tissues in the saltasaurine titanosaurs could be described as either medullary bone or pathological bone. Furthermore, we show that similar endosteally formed well-vascularised bone tissue is fairly widely distributed among nondinosaurian Archosauriformes, and are not restricted to long bones, but can occur in the axial, and dermal skeleton. We propose that independent evidence is required to verify whether vascularised endosteal bone tissues in extinct archosaurs are pathological or reproductive in nature. PMID:27112710

  8. Vitund og ímynd Adidas, Nike og Under Armour

    OpenAIRE

    Sara Úlfarsdóttir 1991

    2016-01-01

    Ritgerð þessi fjallar um rannsókn á ímynd og vitund íþróttavörumerkjanna Adidas, Nike og Under Armour. Fyrirtæki sem hanna íþróttafatnað hafa undanfarin ár fært út kvíarnar og hafa nú hafið framleiðslu á íþróttafatnaði til daglegrar notkunar og jafnvel sem tískufatnað. Þetta kemur til af því að fólk er almennt farið að nota íþróttaföt dagsdaglega en ekki einungis við íþróttaiðkun. Markmið rannsóknarinnar byggir á því að kanna hvort íþróttavörumerkin séu að koma þeirri ímynd og vitund á fr...

  9. Erosion simulation of first wall beryllium armour after ITER transient heat loads and runaway electrons action

    International Nuclear Information System (INIS)

    Beryllium is foreseen as plasma facing armour for the first wall (FW) in ITER in form of Be-clad blanket modules in macrobrush design with brush size about 8-10 cm. In ITER significant heat loads during transient events (TE) and runaway electrons impact are expected at the main chamber wall that may leads to the essential damage of the Be armour. The main mechanisms of metallic target damage remain surface melting, evaporation, and melt motion, which determine the life-time of the plasma facing components. The melt motion damages of Be macrobrush armour caused by the tangential friction force and the J x B forces are analyzed for bulk Be and different sizes of Be-brushes. The damage of the FW due to heat loads caused by runaway electrons is numerically simulated.

  10. Ballistic Behaviour of Thick Steel Armour Plate under Oblique Impact : Experimental Investigation II

    Directory of Open Access Journals (Sweden)

    S. N. Dikshit

    1999-07-01

    Full Text Available The ballistic behaviour of thick steel armour plate at different obliquities has been investigated. Ballistic experiments were conducted in the velocity range 300-800 mls at 0°, 15°, 30° and 45° obliquity .A steel, conical projectile or 6.1 mm diameter was impacted on a 10 mm thick steel armour plate. At 30° and 45° obliquity, the plate offers protection up to a striking velocity of 800 mls. At zero obliquity, the plate provides protection below 6~ m/s. The depth of penetration decreases with increasing obliquity. The plate resistance does not decrease at higher obliquity observed in an earlier work.

  11. On modelling of lateral buckling failure in flexible pipe tensile armour layers

    DEFF Research Database (Denmark)

    Østergaard, Niels Højen; Lyckegaard, Anders; Andreasen, Jens H.

    2012-01-01

    In the present paper, a mathematical model which is capable of representing the physics of lateral buckling failure in the tensile armour layers of flexible pipes is introduced. Flexible pipes are unbounded composite steel–polymer structures, which are known to be prone to lateral wire buckling...... when exposed to repeated bending cycles and longitudinal compression, which mainly occurs during pipe laying in ultra-deep waters. On the basis of multiple single wire analyses, the mechanical behaviour of both layers of tensile armour wires can be determined. Since failure in one layer destabilises...

  12. Hybrid S2/Carbon Epoxy Composite Armours Under Blast Loads

    Science.gov (United States)

    Dolce, F.; Meo, Michele; Wright, A.; French, M.; Bernabei, M.

    2012-06-01

    Civil and military structures, such as helicopters, aircrafts, naval ships, tanks or buildings are susceptible to blast loads as terroristic attacks increases, therefore there is the need to design blast resistant structures. During an explosion the peak pressure produced by shock wave is much greater than the static collapse pressure. Metallic structures usually undergo large plastic deformations absorbing blast energy before reaching equilibrium. Due to their high specific properties, fibre-reinforced polymers are being considered for energy absorption applications in blast resistant armours. A deep insight into the relationship between explosion loads, composite architecture and deformation/fracture behaviour will offer the possibility to design structures with significantly enhanced energy absorption and blast resistance performance. This study presents the results of a numerical investigation aimed at understanding the performance of a hybrid composite (glass/carbon fibre) plate subjected to blast loads using commercial LS-DYNA software. In particular, the paper deals with numerical 3D simulations of damages caused by air blast waves generated by C4 charges on two fully clamped rectangular plates made of steel and hybrid (S2/Carbon) composite, respectively. A Multi Materials Arbitrary Lagrangian Eulerian (MMALE) formulation was used to simulate the shock phenomenon. For the steel plates, the Johnson-Cook material model was employed. For the composite plates both in-plane and out-of-plane failure criteria were employed. In particular, a contact tiebreak formulation with a mixed mode failure criteria was employed to simulate delamination failure. As for the steel plates the results showed that excellent correlation with the experimental data for the two blast load conditions in terms of dynamic and residual deflection for two different C4 charges. For the composite plates the numerical results showed that, as expected, a wider delamination damage was observed

  13. Numerical Simulation of Ballistic Impact on Armour Plate with a Simple Plasticity Model

    Directory of Open Access Journals (Sweden)

    Vijayabaskar Narayanamurthy

    2014-01-01

    Full Text Available Ballistic impact of a steel projectile on armour steel plate is examined by numerical simulations using 3-D nonlinear dynamic explicit finite element code ANSYS LS-DYNA. Simulations are attempted using a simple strain rate dependent plasticity model that can capture large strain, strain rate hardening and fracture encountered at high velocity ballistic impacts. Initial simulations are carried out for a cylindrical bullet with a semi-spherical nose shape impacting a military vehicle door at two different velocities as a test problem. This is then extended to simulate a real problem of armour piercing shot impact on a thick armour steel plate at ordnance velocity regime. The former is compared with results reported in published literature while the latter is assessed with the experimental findings. The deformation pattern generated in the deformed armour plate, residual projectile velocity and displacement of the projectile are taken as the necessary parameters for evaluating the results of simulation. The study presented in this paper demonstrates the effectiveness of the adopted simple plasticity model to simulate a highly nonlinear phenomenon to reasonably predict the physically measurable impact parameters.Defence Science Journal, Vol. 64, No. 1, January 2014, DOI:10.14429/dsj.64.4521

  14. Energy Absorption and Dynamic Deformation of Backing Material for Ballistic Evaluation of Body Armour

    Directory of Open Access Journals (Sweden)

    Debarati Bhattacharjee

    2013-09-01

    Full Text Available The measurement of back face signature (BFS or behind armour blunt trauma (BABT is a critical aspect of ballistic evaluation of body armour. BFS is the impact experienced by the armour wearing body, when subjected to a non-penetrating projectile. Mineral or polymeric clay is used to measure the BFS. In addition to stopping the projectile, the body armour can be used only when the BFS also falls within permissible limits. The extent of the BFS depends upon the behavior of the backing material in different loading conditions and prior history. This paper explains some of the studies carried out on the backing material used for ballistic evaluation in Terminal Ballistics Research Laboratory, Chandigarh. It has been observed that the backing material is highly non-linear viscoelastic in nature. The depth of deformation is also linearly proportional to the impact energy and temperature. The effect of time on the depth of deformation is gradual and does not influence the BFS values during a standard ballistic evaluation comprising of 6-8 shots.Defence Science Journal, 2013, 63(5, pp.462-466, DOI:http://dx.doi.org/10.14429/dsj.63.3821

  15. On the use of flat tile armour in high heat flux components

    International Nuclear Information System (INIS)

    The possibility to have a flat tile geometry for those high heat flux components subjected to a convective heat flux (namely the divertor dump target, lower vertical target, and the limiter) has been investigated. Because of the glancing incidence of the power load, if an armour tile falls off an extremely high heat flux hits the leading edge of the adjacent tile. As a result a rapid temperature increase occurs in the armour-heat sink joint. The heat flux to the water coolant also increases rapidly up to a factor of 1.7 and 2.3 for a beryllium and CFC armour, respectively, thus causing possible critical heat flux problems. Thermal stresses in the armour-heat sink joint double in less than 0.4 s and triplicate after 1 s thus leading to a possible cascade failure. Therefore the use of a flat tile geometry for these components does not seem to be appropriate. In this case a monoblock geometry gives a much more robust solution. (orig.)

  16. Biology of two species of Microcera associated with armoured scales on citrus in Australia

    Science.gov (United States)

    Microcera coccophila has been regarded as an entomopathogen of armoured scales in Australia since the late 1800s. We confirmed its identity using morphological and molecular data. In addition, we report the related species M. larvarum for the first time in Australia. The sexual and asexual states of...

  17. Cold Cracking of Flux Cored Arc Welded Armour Grade High Strength Steel Weldments

    Institute of Scientific and Technical Information of China (English)

    G.Magudeeswaran; V.Balasubramanian; G.Madhusudhan Reddy

    2009-01-01

    In this investigation, an attempt has been made to study the influence of welding consumables on the factors that influence cold cracking of armour grade quenched and tempered (Q&T) steel welds. Flux cored arc welding (FCAW) process were used making welds using austenitic stainless steel (ASS) and low hydrogen ferritic steel (LHF) consumables. The diffusible hydrogen levels in the weld metal of the ASS and LHF consumables were determined by mercury method. Residual stresses were evaluated using X-ray stress analyzer and implant test was carried out to study the cold cracking of the welds. Results indicate that ASS welds offer a greater resistance to cold cracking of armour grade Q&T steel welds.

  18. Arc welding of high strength aluminium alloys for armour systems applications

    OpenAIRE

    Pickin, Craig Graeme

    2011-01-01

    The ternary Al-Cu-Mg system 2xxx series aluminium alloys were examined as construction materials for armour system applications based upon comparable ballistic properties to the currently employed Al-7xxx series alloys. Utilising MIG welding solidification cracking was evident when welding constrained Al-2024 candidate base material using Al-2319 filler, the only available consumable wire for this series. A previously developed thermodynamic model suggested that an incompatible...

  19. The Application of Load-cell Technique in the Study of Armour Unit Responses to Impact Loads

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Zhou

    The slender, complex types of armour units, such as Tetrapods and Dolosse are widely used for rubble mound breakwaters. Many of the recent failures of such structures were caused by unforeseen early breakage of the units, thus revealing an inbalance between the strength (structural integrity) of ...... loads on slender armour units can be studied by load-cell technique. Moreover, the paper presents Dolos design diagrams for the prediction of both breakage and hydraulic stability....... the units and the hydraulic stability (resistance to displacements) of the armour layers. Breakage is caused by stresses from static, pulsating and impact loads. Impact load generated stresses are difficult to investigate due to non-linear scaling laws. The paper describes a method by which impact...

  20. Characteristics of martensite as a function of the Ms temperature in low-carbon armour steel plates

    International Nuclear Information System (INIS)

    The microstructure, morphology, crystal structure and surface relief of martensite in a number of experimental armour steel plates with different Ms temperatures were analysed. Atomic force microscopy, thin foil transmission electron microscopy and scanning electron microscopy allowed the identification of three groups of low-carbon martensitic armour steels. The investigation showed that the size of individual martensite products (plates or packets, laths or blocks) increases as the Ms temperature increases. Comparison of ballistic performances suggests that the morphology (plate or lath) and size of the individual martensite products dictate the effective 'grain size' in resisting fracture or perforation due to ballistic impact.

  1. Comparison of armoured laryngeal mask airway with endotracheal tube for adenotonsillectomy

    International Nuclear Information System (INIS)

    To assess the reliability of armoured laryngeal mask airway for adenotonsillectomy and to compare the haemodynamic changes during anaesthesia with those of endotracheal tube. A total of 100 patients undergoing adenotonsillectomy between ages 10-35 years and ASA I status were enrolled for the study. Two groups with 50 patients in each group were formed. Group I patients underwent surgery with armoured laryngeal mask airway while group II underwent surgery with endotracheal intubation. Baseline heart rate, systolic blood pressure and diastolic blood pressure were noted pre-operatively, one minute after insertion and every five minutes after induction in both the groups. A change in all these haemodynamic parameters from the baseline was noted. The effect of Boyle Davis Gag and adequacy of surgical access were also noted. Occurrence of cough, laryngospasm and stridor were noted at the time of recovery in both the groups. Baseline variables in both groups were identical. Surgical access was adequate in 48/50 patients in group I while it was adequate in 49/50 patients in group II. The frequencies of cough, laryngeal spasm and stridor were lower in group I. In group I, there was insignificant change from baseline in heart rate, systolic and diastolic blood pressure at one, five and ten minutes after induction. In group II, significant change from baseline was observed in heart rate (p <0.01), systolic blood pressure (p <0.05) and diastolic blood pressure (p <0.05). (author)

  2. Energy Absorption and Dynamic Deformation of Backing Material for Ballistic Evaluation of Body Armour

    Directory of Open Access Journals (Sweden)

    Debarati\tBhattacharjee

    2014-09-01

    Full Text Available The\tmeasurement\tof back face signature\t(BFS or\tbehind armour\tblunt trauma (BABT is\ta critical\taspect of ballistic evaluation of body\tarmour. BFS is the impact experienced by the\tarmour wearing body,\twhen subjected to\ta non-penetrating\tprojectile. Mineral\tor polymeric\tclay\tis used to measure the\tBFS. In addition to stopping the\tprojectile,\tthe body armour can be used only when the BFS also falls within\tpermissible limits.\tThe\textent of\tthe BFS depends upon the\tbehavior\tof the backing material\tin different loading conditions and prior history.\tThis\tpaper explains some of the\tstudies carried out on the backing\tmaterial used for ballistic evaluation\tin Terminal Ballistics Research\tLaboratory, Chandigarh. It has been observed\tthat\tthe backing material is highly non-linear\tviscoelastic in nature. The depth\tof\tdeformation is also linearly\tproportional to the\timpact\tenergy\tand\ttemperature. The\teffect of time\ton the depth of deformation\tis gradual and does\tnot influence the BFS values during a\tstandard\tballistic evaluation comprising of 6-8\tshots.

  3. Simulation of tungsten armour cracking due to small ELMs in ITER

    International Nuclear Information System (INIS)

    Simulations of tungsten armour cracking under small ELM-like plasma heat load, which does not cause surface melting, have been performed using the PEGASUS-3D code. A dedicated series of experiments have been performed in the QSPA-Kh50 facility for measurements of the unknown tungsten thermophysical properties and for verification of the PEGASUS-3D simulation results. The simulations revealed that a cellular crack network with average mesh size Λ ∼ 0.5 mm formed after first ELMs and the pattern does not change further. With increasing number of repetitive ELMs loads, the average crack width Δ(n) has a maximum value Δm. The ratio of Δm/Λ is equal to the tungsten thermal expansion at the maximum surface temperature. Δ(n) tends to this value exponentially. The number of ELMs nm needed for Δ stabilization depends on the ELMs energy density and time duration, nm ∼ 300 for the simulated ELMs of 0.45 MJ/m2 and 0.25 ms duration. The PEGASUS-3D code is prepared for simulations of tungsten armour damage under action of ELMs of various energy deposition and time duration. These parameters of ELMs depend on ITER regimes of operation and on how successful will be the efforts on ELMs mitigation.

  4. Aspect of use of ultrahigh molecular weight polyethylene (uhmwpe) as biomaterial and as armour material (abstract)

    International Nuclear Information System (INIS)

    Among the known polymeric materials, ultrahigh molecular weight polyethylene (UHMWPE) has unique properties as a biomaterial as well as armour material. Its high strength and very high modulus makes it an alternate candidate as body armour for example bullet proof vest. The drawn fibers from this material are best known for their break strength and compete with the steel and carbon fibers. On the other hand, its extremely high molar mass imparts outstanding wear resistance and impact toughness better than any other polymer which makes it a better choice as biomaterial used in hip and knee transplants. As a biomaterial, when body transplants are gamma sterilized, their shelf life depends upon the number and nature of free radicals produced during sterilization. These long-lived radicals ultimately affect the wear properties of hip and knee transplants. The Electron Spin Resonance (ESR) technique used to determine the concentration and nature of free radicals in about 16 years old powder, fibers and ram-extruded bar samples shows that at low microwave power (0.01 mW), polyenyl radicals become prominent while at high microwave power (160 mW), oxygen-centered radicals show their identity. The ESR study also exhibits that the concentration of free radicals depends upon the crystallinities of different morphologies known i.e powder, extruded bars and drawn fibers. Differential scanning calorimetry shows the order of crystallinity as: fiber > extruded bars > powder. (author)

  5. Finite Element and Experimental Analyses of an Armoured Vehicle Subjected to Landmine Blast

    Directory of Open Access Journals (Sweden)

    Atıl Erdik

    2015-11-01

    Full Text Available Landmines severely threaten the armoured vehicles. The principal objective is to present a methodology for blast simulations of vehicles subjected to landmine explosions. First, free field blast experiment of 2 kg TNT charge in a steel pot is carried out to validate the blast parameters used in the numerical simulation. Overpressure-time history collected in the free field blast experiment is compared to the numerical simulation results. Numerical simulations are performed in LS-DYNA hydrocode that employs Arbitrary Lagrangian Eulerian formulation enabling a fully coupled interaction between the blast wave, the detonation gases, and the vehicle. Second, the full-scale field test of an armoured vehicle exposed to 6 kg of TNT charge in a steel pot underneath the rear end of the vehicle is conducted. Maximum dynamic deformations measured inside the vehicle are compared to the results calculated in the numerical simulation. Results show that the numerical simulation is in good agreement with the full-scale field test.

  6. The Application of Load-cell Technique in the Study of Armour Unit Responses to Impact Loads Tests

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Z.

    1995-01-01

    The slender, complex types of armour units, such as Tetrapods and Dolosse are widely used for rubble mound breakwaters. Many of the recent failures of such structures were caused by unforeseen early breakage of the units, thus revealing an in balance between the strength (structural integrity) of...

  7. Mechanical adaptability of the Bouligand-type structure in natural dermal armour.

    Science.gov (United States)

    Zimmermann, Elizabeth A; Gludovatz, Bernd; Schaible, Eric; Dave, Neil K N; Yang, Wen; Meyers, Marc A; Ritchie, Robert O

    2013-01-01

    Arapaima gigas, a fresh water fish found in the Amazon Basin, resist predation by piranhas through the strength and toughness of their scales, which act as natural dermal armour. Arapaima scales consist of a hard, mineralized outer shell surrounding a more ductile core. This core region is composed of aligned mineralized collagen fibrils arranged in distinct lamellae. Here we show how the Bouligand-type (twisted plywood) arrangement of collagen fibril lamellae has a key role in developing their unique protective properties, by using in situ synchrotron small-angle X-ray scattering during mechanical tensile tests to observe deformation mechanisms in the fibrils. Specifically, the Bouligand-type structure allows the lamellae to reorient in response to the loading environment; remarkably, most lamellae reorient towards the tensile axis and deform in tension through stretching/sliding mechanisms, whereas other lamellae sympathetically rotate away from the tensile axis and compress, thereby enhancing the scale's ductility and toughness to prevent fracture. PMID:24129554

  8. Strain rate effects on mechanical properties in tension of aluminium alloys used in armour applications

    Science.gov (United States)

    Cadoni, E.; Dotta, M.; Forni, D.; Bianchi, S.; Kaufmann, H.

    2012-08-01

    The mechanical properties in tension of two aluminium alloys (AA5059-H131 and AA7039-T651) used in armour applications were determined from tests carried out over a wide range of strain-rates on round specimens. The experimental research was developed in the DynaMat laboratory of the University of Applied Sciences of Southern Switzerland. The target strain rates were set at the following four levels: 10-3, 30, 300 and 1000s-1. The quasi-static tests were performed with a universal electromechanical machine, whereas a hydro-pneumatic machine and a Split Hopkinson Tensile Bar apparatus were used for medium and high strain-rates respectively. The required parameters by the Johnson-Cook constitutive law were also determined.

  9. Strain rate effects on mechanical properties in tension of aluminium alloys used in armour applications

    Directory of Open Access Journals (Sweden)

    Bianchi S.

    2012-08-01

    Full Text Available The mechanical properties in tension of two aluminium alloys (AA5059-H131 and AA7039-T651 used in armour applications were determined from tests carried out over a wide range of strain-rates on round specimens. The experimental research was developed in the DynaMat laboratory of the University of Applied Sciences of Southern Switzerland. The target strain rates were set at the following four levels: 10−3, 30, 300 and 1000s−1. The quasi-static tests were performed with a universal electromechanical machine, whereas a hydro-pneumatic machine and a Split Hopkinson Tensile Bar apparatus were used for medium and high strain-rates respectively. The required parameters by the Johnson-Cook constitutive law were also determined.

  10. In-situ change and repairing method of armour tile made of carbon fiber composite material in divertor

    International Nuclear Information System (INIS)

    A joint portion of a damaged armour tile of a carbon fiber composite material and a divertor substrate is locally heated spontaneously to re-melt the soldering. Then, the damaged tile is removed and the portion where the tile is removed is heated again to melt the soldering, then a tile for exchange is joined. Alternatively, a thermosetting type adhesive is coated on the surface of the damaged armour tile made of carbon fiber composite material on the divertor, and a tile for repairing is adhered thereon then the joint surface is locally heated to cure the adhesive. For local heating, for example, high frequency heating or dielectric heating is used. It is preferably conducted by remote handling by using robot arms under vacuum in an vacuum vessel of the thermonuclear device. The operations of the heating and pressurization for the joint surface are preferably repeated for several times. (N.H.)

  11. Improvement of non destructive infrared test bed SATIR for examination of actively cooled tungsten armour Plasma Facing Components

    International Nuclear Information System (INIS)

    Highlights: • Non destructive infrared techniques for control ITER like PFCs. • Reflective surface such as W induce a measurement temperature error. • Numerical data processing by evaluation of the local emissivity. • SATIR test bed can control metallic surface with low and variable emissivity. -- Abstract: For steady state (magnetic) thermonuclear fusion devices which need large power exhaust capability and have to withstand heat fluxes in the range 10–20 MW m−2, advanced Plasma Facing Components (PFCs) have been developed. The importance of PFCs for operating tokamaks requests to verify their manufacturing quality before mounting. SATIR is an IR test bed validated and recognized as a reliable and suitable tool to detect cooling defaults on PFCs with CFC armour material. Current tokamak developments implement metallic armour materials for first wall and divertor; their low emissivity causes several difficulties for infrared thermography control. We present SATIR infrared thermography test bed improvements for W monoblocks components without defect and with calibrated defects. These results are compared to ultrasonic inspection. This study demonstrates that SATIR method is fully usable for PFCs with low emissivity armour material

  12. Effect of Flyer Plate Velocity and Rate of Crater Expansion on Performance of Explosive Reactive Armour

    Directory of Open Access Journals (Sweden)

    H.S. Yadav

    2002-10-01

    Full Text Available "The reduction in the penetration power of the jet due to its interaction with an obliquely moving plate of explosive reactive armour (ERA sandwich has been studied. It has been assumed that the length of the jet, which gets disturbed due to its interaction with the edge of the hole made by the impact of the tip of the jet when the plate was stationary, does not contribute to penetration in the target. The jet length, which comes out of the hole undisturbed, penetrates the target. This length of the jet has been calculated considering the variation in plate velocity and rate of expansion of the crater in the plate with time. The time taken by the jet to shift its position from the centre to the wall of the hole has been determined for different velocities of the sandwich plate and varying expansion rates of the hole produced by the jet in the plate, corresponding to a constant velocity of the jet. This analysis has been used to obtain the length of undisturbed jet coming out of the hole and its penetration in the target. The present study establishes the effect of the plate velocity and rate of crater expansion on the performance of the ERA. It has been found that both these parameters affect the performance of the ERA, and the metal plates of lower density and higher strength make the ERA more effective.

  13. Transcriptome Analysis of Kiwifruit (Actinidia chinensis) Bark in Response to Armoured Scale Insect (Hemiberlesia lataniae) Feeding.

    Science.gov (United States)

    Hill, M Garry; Wurms, Kirstin V; Davy, Marcus W; Gould, Elaine; Allan, Andrew; Mauchline, Nicola A; Luo, Zhiwei; Ah Chee, Annette; Stannard, Kate; Storey, Roy D; Rikkerink, Erik H

    2015-01-01

    The kiwifruit cultivar Actinidia chinensis 'Hort16A' is resistant to the polyphagous armoured scale insect pest Hemiberlesia lataniae (Hemiptera: Diaspididae). A cDNA microarray consisting of 17,512 unigenes selected from over 132,000 expressed sequence tags (ESTs) was used to measure the transcriptomic profile of the A. chinensis 'Hort16A' canes in response to a controlled infestation of H. lataniae. After 2 days, 272 transcripts were differentially expressed. After 7 days, 5,284 (30%) transcripts were differentially expressed. The transcripts were grouped into 22 major functional categories using MapMan software. After 7 days, transcripts associated with photosynthesis (photosystem II) were significantly down-regulated, while those associated with secondary metabolism were significantly up-regulated. A total of 643 transcripts associated with response to stress were differentially expressed. This included biotic stress-related transcripts orthologous with pathogenesis related proteins, the phenylpropanoid pathway, NBS-LRR (R) genes, and receptor-like kinase-leucine rich repeat signalling proteins. While transcriptional studies are not conclusive in their own right, results were suggestive of a defence response involving both ETI and PTI, with predominance of the SA signalling pathway. Exogenous application of an SA-mimic decreased H. lataniae growth on A. chinensis 'Hort16A' plants in two laboratory experiments. PMID:26571404

  14. Flat tile armour cooled by hypervapotron tube: a possible technology for ITER

    International Nuclear Information System (INIS)

    Carbon fibre composite (CFC) flat tile armours for actively cooled plasma facing components (PFC's) are an important challenge for controlled fusion machine. Flat tile concepts, water cooled by tubes, were studied, developed, tested and finally experienced with success in Tore Supra. The components were designed for 10 MW/m2 and mock-ups were successfully fatigue tested at 15 MW/m2, 1000 cycles. For ITER, a tube-in-tile concept was developed and mock-ups sustained up to 25 MW/m2 for 1000 cycles without failure. Recently flat tile armored mock-ups cooled by Hypervapotron tube successfully sustained a cascade failure test under a mean heat flux of 10 MW/m2 but with a doubling of the heat flux on some tiles to simulate missing tiles (500 cycles). This encouraging results lead to reconsider the limits for flat tile concept when cooled by Hypervapotron tube. New tests are now scheduled to investigate these limits notably in regards to the ITER requirements. The concept could also be experimented in Tore Supra by installing a new limiter into the machine. (authors)

  15. Uncovering three-dimensional gradients in fibrillar orientation in an impact-resistant biological armour

    Science.gov (United States)

    Zhang, Y.; Paris, O.; Terrill, N. J.; Gupta, H. S.

    2016-05-01

    The complex hierarchical structure in biological and synthetic fibrous nanocomposites entails considerable difficulties in the interpretation of the crystallographic texture from diffraction data. Here, we present a novel reconstruction method to obtain the 3D distribution of fibres in such systems. An analytical expression is derived for the diffraction intensity from fibres, explaining the azimuthal intensity distribution in terms of the angles of the three dimensional fibre orientation distributions. The telson of stomatopod (mantis shrimp) serves as an example of natural biological armour whose high impact resistance property is believed to arise from the hierarchical organization of alpha chitin nanofibrils into fibres and twisted plywood (Bouligand) structures at the sub-micron and micron scale. Synchrotron microfocus scanning X-ray diffraction data on stomatopod telson were used as a test case to map the 3D fibre orientation across the entire tissue section. The method is applicable to a range of biological and biomimetic structures with graded 3D fibre texture at the sub-micron and micron length scales.

  16. Ballistic Performance of Alumina and Zirconia-toughened Alumina Against 7.62 Armour Piercing Projectile

    Directory of Open Access Journals (Sweden)

    S G. Savio

    2014-09-01

    Full Text Available A study was carried out to compare the ballistic performance of high purity alumina and zirconia-toughened alumina (ZTA using depth of penetration (DoP test configuration against 7.62 mm armour piercing (AP ammunition. The effect of tile thickness on the differential efficiency factor (DEF was studied for tile thickness in the range of 3 mm to 6 mm for alumina tiles and 3 mm to 5 mm for ZTA tiles. The DEF is found to increase as tile thickness increases. An analysis on the failed shots showed that the residual shot weight does not follow a single linear relationship with ceramic tile thickness unlike the residual DoP for all thicknesses of tiles. Post-ballistic analysis on ceramic powder for particle size distribution was carried out and the results are presented.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.477-483, DOI:http://dx.doi.org/10.14429/dsj.64.6745

  17. Sounds, behaviour, and auditory receptors of the armoured ground cricket, Acanthoplus longipes.

    Science.gov (United States)

    Kowalski, Kerstin; Lakes-Harlan, Reinhard

    2010-01-01

    The auditory sensory system of the taxon Hetrodinae has not been studied previously. Males of the African armoured ground cricket, Acanthoplus longipes (Orthoptera: Tettigoniidae: Hetrodinae) produce a calling song that lasts for minutes and consists of verses with two pulses. About three impulses are in the first pulse and about five impulses are in the second pulse. In contrast, the disturbance stridulation consists of verses with about 14 impulses that are not separated in pulses. Furthermore, the inter-impulse intervals of both types of sounds are different, whereas verses have similar durations. This indicates that the neuronal networks for sound generation are not identical. The frequency spectrum peaks at about 15 kHz in both types of sounds, whereas the hearing threshold has the greatest sensitivity between 4 and 10 kHz. The auditory afferents project into the prothoracic ganglion. The foreleg contains about 27 sensory neurons in the crista acustica; the midleg has 18 sensory neurons, and the hindleg has 14. The auditory system is similar to those of other Tettigoniidae. PMID:20569136

  18. The Influence of impact on Composite Armour System Kevlar-29/polyester-Al2O3

    International Nuclear Information System (INIS)

    An experimental investigation of high velocity impact responses of composite laminated plates using a helium gas gun has been presented in this paper. The aim of this study was to develop the novel composite structure that meets the specific requirements of ballistic resistance which used for body protections, vehicles and other applications. Thus the high velocity impact tests were performed on composite Kevlar-29 fiber/polyester resin with alumina powder (Al2O3). The impact test was conducted by using a cylindrical steel projectile of 7.62mm diameter at a velocity range of 160-400 m/s. The results (shown in this work) are in terms of varying plate thickness and the amount of energy absorbed by the laminated plates meanwhile we obtained that the 12mm thickness of composite plate suitable for impact loading up to 200m/s impact velocity. Therefore this composite structure (it is used to reduce the amount of Kevlar) considered most economical armoure products. We used the ANSYS AUTODYN 3D- v.12 software for our simulations. The results have been obtained a4.1% maximum errors with experimental work of energy absorption.

  19. Body armour: the effect of load, exercise and distraction on landing forces.

    Science.gov (United States)

    Dempsey, Paddy C; Handcock, Phil J; Rehrer, Nancy J

    2014-01-01

    We investigated the effect of added load and intense exercise on jump and landing performance and ground reaction force (GRF) during landings where attentional demand was varied. Fifty-two males (37 ± 9.2 years, 180.7 ± 6.1 cm, 90.2 ± 11.6 kg, maximal aerobic fitness (VO(₂max)) 50 ± 8.5 ml (.) kg(-1 .) min(-1), BMI 27.6 ± 3.1, mean ± s) completed a VO(₂max) test. Experimental sessions were completed (≥4 days in between) in a randomised counterbalanced order, one while wearing body armour and appointments (loaded) and one without load (unloaded). A vertical jump, a drop landing concentrating on safe touchdown, a drop jump and a drop landing with an attentional distraction were performed. These were repeated 1 min after a 5-min treadmill run. Mean jump height decreased by 12% (P task. Peak GRFs were increased by 13-19% with loading (P task demands and a further by 4-9% following intense exercise. The distracted drop landing had significantly higher GRFs compared to all other landings. Results demonstrate that added load impacts on jumping and landing performance, an effect that is amplified by prior intense exercise, and distraction during landing. Such increases in GRF apply to police officer performance in their duties and may increase the risk of injury. PMID:24050682

  20. Simulations of material damage to divertor and first wall armour under ITER transient loads by modelling and experiments

    International Nuclear Information System (INIS)

    Operation of ITER at high fusion gain is assumed to be the H-mode. A characteristic feature of this regime is the transient energy release (TE) from the confined plasma onto plasma facing components (PFCs), which can play a determining role in lifetime of these components. The expected fluxes on the ITER PFCs during transients are: Type I ELM Q = 0.5 - 4 MJ/m2 in timescales t = 0.3 - 0.6 ms, and thermal quench Q = 2 - 13 MJ/m2 with t = 1 - 3 ms. CFC and tungsten macrobrush armour are foreseen as PFCs for ITER divertor and Be - as FW armour. During the intense TE in ITER the evaporation (CFC, W, Be) and surface melting and melt splashing (W and Be) are seen as the main mechanisms of PFC erosion. A noticeable erosion of CFC PAN fibres and rather intense crack formation for the W targets were observed in plasma gun experiments at rather small heat loads at which the melt damage to W armour is not substantial. The expected erosion of the ITER PFCs TE can be properly estimated by numerical simulations validated against erosion experiments at the plasma gun facilities QSPA-T, MK- 200UG and QSPA-Kh50. Within collaboration between EU fusion programme and Russian Federation, CFC and W macrobrush targets manufactured in EU were exposed to multiple ITER TE-like loads with Q = 0.5 - 2.2 MJ/m2 and t = 0 .5 ms at the QSPA-T. The measured erosion was used to validate the modelling codes developed in FZK (PEGASUS, MEMOS, and others), which are then applied to model the erosion of the divertor and main chamber ITER PFCs under expected transient loads in ITER. Numerical simulations performed for the expected ITER-like loads predicted: a significant erosion of the CFC target for Q > 0.5 MJ/m2 was caused by the inhomogeneous structure of the CFC; the W macrobrush structure is effective in preventing gross melt layer displacement. Optimization of macrobrush geometry to minimize melt splashing is done. Different mechanisms of melt splashing are compared with the results obtained in QSPA

  1. Experimental and numerical analysis of the dynamic behaviour in tension of an armour steel for applications in defence industry

    Directory of Open Access Journals (Sweden)

    Cadoni Ezio

    2015-01-01

    Full Text Available The dynamic behaviour of armour steel in tension was investigated over a wide range of strain-rates on round specimens. The experiments were carried out by means of a Split Hopkinson Tensile Bar device and by a Hydro Pneumatic Machine. The target strain rate were set at the following six levels: 10−3, 5, 25, 100, 500 and 1000 s−1. Two material models were calibrated and used to replicate the experiments and to simulate blasting event on steel plate. Finally, the two responses are compared.

  2. Large-scale scour of the sea floor and the effect of natural armouring processes, land reclamation Maasvlakte 2, port of Rotterdam

    Science.gov (United States)

    Boer, S.; Elias, E.; Aarninkhof, S.; Roelvink, D.; Vellinga, T.

    2007-01-01

    Morphological model computations based on uniform (non-graded) sediment revealed an unrealistically strong scour of the sea floor in the immediate vicinity to the west of Maasvlakte 2. By means of a state-of-the-art graded sediment transport model the effect of natural armouring and sorting of bed material on the scour process has been examined. Sensitivity computations confirm that the development of the scour hole is strongly reduced due to the incorporation of armouring processes, suggesting an approximately 30% decrease in terms of erosion area below the -20m depth contour. ?? 2007 ASCE.

  3. Effect of welding processes and consumables on fatigue crack growth behaviour of armour grade quenched and tempered steel joints

    Institute of Scientific and Technical Information of China (English)

    G. MAGUDEESWARAN; V. BALASUBRAMANIAN; G. MADHUSUDHAN REDDY

    2014-01-01

    Quenched and Tempered (Q&T) steels are widely used in the construction of military vehicles due to its high strength to weight ratio and high hardness. These steels are prone to hydrogen induced cracking (HIC) in the heat affected zone (HAZ) after welding. The use of austenitic stainless steel (ASS) consumables to weld the above steel was the only available remedy because of higher solubility for hydrogen in austenitic phase. The use of stainless steel consumables for a non-stainless steel base metal is not economical. Hence, alternate consumables for welding Q&T steels and their vulnerability to HIC need to be explored. Recent studies proved that low hydrogen ferritic steel (LHF) consumables can be used to weld Q&T steels, which can give very low hydrogen levels in the weld deposits. The use of ASS and LHF consumables will lead to distinct microstructures in their respective welds. This microstructural heterogeneity will have a drastic influence in the fatigue crack growth resistance of armour grade Q&T steel welds. Hence, in this investigation an attempt has been made to study the influence of welding con-sumables and welding processes on fatigue crack growth behaviour of armour grade Q&T Steel joints. Shielded metal arc welding (SMAW) and Flux cored arc welding (FCAW) were used for fabrication of joints using ASS and LHF consumables. The joints fabricated by SMAW process using LHF consumable exhibited superior fatigue crack growth resistance than all other joints.

  4. Influence of the vacuum resin process, on the ballistic behaviour of lightweight armouring solutions

    Science.gov (United States)

    Lefebvre, M.; Boussu, F.; Coutellier, D.; Vallee, D.

    2012-08-01

    The armour of vehicles against conventional threats is mainly composed with steel or aluminium panels. Efficient heavy solutions exist, but the involved industries require new lightweight structures. Moreover, unconventional threats as IEDs (Improvised Explosive Devices) may cause severe damages on these structural and protective panel solutions. Thus, combination of aluminium or steel plates with textile composite structures used as a backing, leads to the mass reduction and better performance under delamination behaviour against these new threats. This paper is a part of a study dealing with the impact behaviour of three warp interlocks weaving structures under Fragment Simulating Projectile (FSP) impact. During this research, several parameters has being studied as the influence of the yarns insertions [1-4], the degradation of the yarns during the weaving process [5-7], and the influence of the resin rate on the ballistic behaviour. The resin rate inside composite materials is dependant on the final application. In ballistic protection, we need to control the resin rate in order to have a deformable structure in order to absorb the maximum of energy. However, with the warp interlocks weaving structure, the yarns insertions induce empty spaces between the yarns where the resin takes place without being evacuated. The resin rate inside the warp interlocks structures is in the most of cases less than 50%, which lead to have brittle and hard material during the impact. Contrary to interlocks structures, the existing protection based on prepreg structure have a high fibres ratio around 88% of weight. That leads to have the best ballistic properties during the impact and good deformability of the structure. The aim of this paper is to evaluate the influence of the resin rate on the ballistic results of the composites materials. For that, we have chosen two kinds of warp interlocks fabrics which were infused with epoxy resin following two processes. The first is a

  5. Influence of the vacuum resin process, on the ballistic behaviour of lightweight armouring solutions

    Directory of Open Access Journals (Sweden)

    Coutellier D.

    2012-08-01

    Full Text Available The armour of vehicles against conventional threats is mainly composed with steel or aluminium panels. Efficient heavy solutions exist, but the involved industries require new lightweight structures. Moreover, unconventional threats as IEDs (Improvised Explosive Devices may cause severe damages on these structural and protective panel solutions. Thus, combination of aluminium or steel plates with textile composite structures used as a backing, leads to the mass reduction and better performance under delamination behaviour against these new threats. This paper is a part of a study dealing with the impact behaviour of three warp interlocks weaving structures under Fragment Simulating Projectile (FSP impact. During this research, several parameters has being studied as the influence of the yarns insertions [1–4], the degradation of the yarns during the weaving process [5–7], and the influence of the resin rate on the ballistic behaviour. The resin rate inside composite materials is dependant on the final application. In ballistic protection, we need to control the resin rate in order to have a deformable structure in order to absorb the maximum of energy. However, with the warp interlocks weaving structure, the yarns insertions induce empty spaces between the yarns where the resin takes place without being evacuated. The resin rate inside the warp interlocks structures is in the most of cases less than 50%, which lead to have brittle and hard material during the impact. Contrary to interlocks structures, the existing protection based on prepreg structure have a high fibres ratio around 88% of weight. That leads to have the best ballistic properties during the impact and good deformability of the structure. The aim of this paper is to evaluate the influence of the resin rate on the ballistic results of the composites materials. For that, we have chosen two kinds of warp interlocks fabrics which were infused with epoxy resin following two

  6. A General Discussion of Problems Related to the Determination of Concrete Armour Unit Stresses Including Specific Results related to Static and Dynamic Stresses in Dolosse

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Zhou

    1989-01-01

    units". This problem is related mainly to the slender types of armour units. The paper discusses the various types of loads, and the practical determination of the wave and gravity induced loads and stresses, especially the model test technique and its restrictions. Examples related to Dolosse are...

  7. A study of the German ‘Gothic’ 15th-century equestrian armour (A21 in the Wallace Collection, London

    Directory of Open Access Journals (Sweden)

    Edge, David

    2001-12-01

    Full Text Available The most famous, indeed iconic, armour in the Wallace Collection, London, is the late 15th century German armour for man and horse (inventory number A21. Unfortunately for the historian of armour, it is also one of the most composite, having been assembled in its present form in the 19th century from elements of at least five armours. Archival research in the Wallace Collection has been combined with metallography in the Conservation Department to attempt to cast some further light upon its origins.

    La armadura más famosa y emblemática de la Wallace Collection de Londres es un arnés para hombre y caballo de finales del siglo XV (inv. A.21. Desafortunadamente para la historia del arte de la armadura es también una de las más heterogéneas, compuesta en el siglo XIX con piezas procedentes de al menos otras cinco armaduras. La investigación archivística en la Wallace Collection se ha compaginado con el estudio metalográfico del Departamento de Conservación para intentar arrojar algo más de luz sobre sus orígenes.

  8. Long-term responses of sandy beach crustaceans to the effects of coastal armouring after the 2010 Maule earthquake in South Central Chile

    Science.gov (United States)

    Rodil, Iván F.; Jaramillo, Eduardo; Acuña, Emilio; Manzano, Mario; Velasquez, Carlos

    2016-02-01

    Earthquakes and tsunamis are large physical disturbances frequently striking the coast of Chile with dramatic effects on intertidal habitats. Armouring structures built as societal responses to beach erosion and shoreline retreat are also responsible of coastal squeeze and habitat loss. The ecological implications of interactions between coastal armouring and earthquakes have recently started to be studied for beach ecosystems. How long interactive impacts persist is still unclear because monitoring after disturbance generally extends for a few months. During five years after the Maule earthquake (South Central Chile, February 27th 2010) we monitored the variability in population abundances of the most common crustacean inhabitants of different beach zones (i.e. upper, medium, and lower intertidal) at two armoured (one concrete seawall and one rocky revetment) and one unarmoured sites along the sandy beach of Llico. Beach morphology changed after the earthquake-mediated uplift, restoring upper- and mid-shore armoured levels that were rapidly colonized by typical crustacean species. However, post-earthquake increasing human activities affected the colonization process of sandy beach crustaceans in front of the seawall. Lower-shore crab Emerita analoga was the less affected by armouring structures, and it was the only crustacean species present at the three sites before and after the earthquake. This study shows that field sampling carried out promptly after major disturbances, and monitoring of the affected sites long after the disturbance is gone are effective approaches to increase the knowledge on the interactive effects of large-scale natural phenomena and artificial defences on beach ecology.

  9. Enhancement of wear and ballistic resistance of armour grade AA7075 aluminium alloy using friction stir processing

    Directory of Open Access Journals (Sweden)

    I. Sudhakar

    2015-03-01

    Full Text Available Industrial applications of aluminium and its alloys are restricted because of their poor tribological properties. Thermal spraying, laser surfacing, electron beam welding are the most widely used techniques to alter the surface morphology of base metal. Preliminary studies reveal that the coating and layering of aluminium alloys with ceramic particles enhance the ballistic resistance. Furthermore, among aluminium alloys, 7075 aluminium alloy exhibits high strength which can be compared to that of steels and has profound applications in the designing of lightweight fortification structures and integrated protection systems. Having limitations such as poor bond integrity, formation of detrimental phases and interfacial reaction between reinforcement and substrate using fusion route to deposit hard particles paves the way to adopt friction stir processing for fabricating surface composites using different sizes of boron carbide particles as reinforcement on armour grade 7075 aluminium alloy as matrix in the present investigation. Wear and ballistic tests were carried out to assess the performance of friction stir processed AA7075 alloy. Significant improvement in wear resistance of friction stir processed surface composites is attributed to the change in wear mechanism from abrasion to adhesion. It has also been observed that the surface metal matrix composites have shown better ballistic resistance compared to the substrate AA7075 alloy. Addition of solid lubricant MoS2 has reduced the depth of penetration of the projectile to half that of base metal AA7075 alloy. For the first time, the friction stir processing technique was successfully used to improve the wear and ballistic resistances of armour grade high strength AA7075 alloy.

  10. Enhancement of wear and ballistic resistance of armour grade AA7075 aluminium alloy using friction stir processing

    Institute of Scientific and Technical Information of China (English)

    I. SUDHAKAR; V. MADHU; G. MADHUSUDHAN REDDY; K. SRINIVASA RAO

    2015-01-01

    Industrial applications of aluminium and its alloys are restricted because of their poor tribological properties. Thermal spraying, laser surfacing, electron beam welding are the most widely used techniques to alter the surface morphology of base metal. Preliminary studies reveal that the coating and layering of aluminium alloys with ceramic particles enhance the ballistic resistance. Furthermore, among aluminium alloys, 7075 aluminium alloy exhibits high strength which can be compared to that of steels and has profound applications in the designing of lightweight fortification structures and integrated protection systems. Having limitations such as poor bond integrity, formation of detrimental phases and interfacial reaction between reinforcement and substrate using fusion route to deposit hard particles paves the way to adopt friction stir processing for fabricating surface composites using different sizes of boron carbide particles as reinforcement on armour grade 7075 aluminium alloy as matrix in the present investigation. Wear and ballistic tests were carried out to assess the performance of friction stir processed AA7075 alloy. Significant improvement in wear resistance of friction stir processed surface composites is attributed to the change in wear mechanism from abrasion to adhesion. It has also been observed that the surface metal matrix composites have shown better ballistic resistance compared to the substrate AA7075 alloy. Addition of solid lubricant MoS2 has reduced the depth of penetration of the projectile to half that of base metal AA7075 alloy. For the first time, the friction stir processing technique was successfully used to improve the wear and ballistic resistances of armour grade high strength AA7075 alloy.

  11. Origins of bone repair in the armour of fossil fish: response to a deep wound by cells depositing dentine instead of dermal bone

    OpenAIRE

    Johanson, Zerina; Smith, Moya; Kearsley, Anton; Pilecki, Peter; Mark-Kurik, Elga; Howard, Charles

    2013-01-01

    The outer armour of fossil jawless fishes (Heterostraci) is, predominantly, a bone with a superficial ornament of dentine tubercles surrounded by pores leading to flask-shaped crypts (ampullae). However, despite the extensive bone present in these early dermal skeletons, damage was repaired almost exclusively with dentine. Consolidation of bone, by dentine invading and filling the vascular spaces, was previously recognized in Psammolepis and other heterostracans but was associated with ageing...

  12. Effect of post weld heat treatment on tensile properties and microstructure characteristics of friction stir welded armour grade AA7075-T651 aluminium alloy

    OpenAIRE

    P Sivaraj; KANAGARAJAN D.; Balasubramanian, V.

    2014-01-01

    This paper reports the effects of post weld heat treatments, namely artificial ageing and solution treatment followed by artificial ageing, on microstructure and mechanical properties of 12 mm thick friction stir welded joints of precipitation hardenable high strength armour grade AA7075-T651 aluminium alloy. The tensile properties, such as yield strength, tensile strength, elongation and notch tensile strength, are evaluated and correlated with the microhardness and microstructural features....

  13. The First South African Armoured Battle in Italy during the Second World War: The Battle of Celleno – 10 June 1944

    Directory of Open Access Journals (Sweden)

    Evert Kleynhans

    2013-02-01

    Full Text Available The formation of 6 South African Armoured Division (6 SA Armd Div, during February 1943, afforded the Union Defence Force (UDF the chance to expand its military capabilities to that of armoured warfare.  An armoured division further offered South Africa the opportunity to equip the UDF with modern fighting equipment and to master the art of combined warfare.  Actual deployment in Italy differed vastly from the training which the division received in North Africa, for Italy was arguably, largely “untankable”.  The Division’s first battle occurred at Celleno, on 10 June 1944, where it was able to “prove” itself by securing its first victory.  As far as secondary sources are concerned, the Battle of Celleno is only superficially covered.  Primary sources are however abundant, thus adding to the rich history which is available on the Division.  This article analyses the Battle of Celleno, fought by 11 SA Armoured Brigade, in the context of the notion of “first battles”.[i] Emphasis will be placed on the training received prior to deployment, the Battle of Celleno, the lessons that were learned by the division at Celleno, and the way these influenced future operations in Italy.  The Division’s combined-arms approach is also evaluated, with specific emphasis on changing patterns of leadership, command, and employment of the Division after Celleno. [i] CE Heller & WA Stofft (eds. America’s first battles 1776–1965. Lawrence, KS: University Press of Kansas, 1986, ix–xiii.

  14. Not armour, but biomechanics, ecological opportunity and increased fecundity as keys to the origin and expansion of the mineralized benthic metazoan fauna

    OpenAIRE

    Cohen, B. L.

    2005-01-01

    This paper offers a new biotic interaction hypothesis for the Cambrian 'explosion' of mineralized, benthic, metazoan diversity. It proposes that organic-mineral composite structures (e.g. shells and muscle lever-arms) originated in Proterozoic lineages of primary larva-like, but reproductively competent, pelagic bilaterians because mineralization was both mechanically and energetically favourable, not because it provided armour against predation. Increased strength and rigidity of composite s...

  15. An experimental investigation of the early dynamic impact behaviour of textile armour systems: Decoupling material from system response

    Science.gov (United States)

    Cepus, Elvis

    This work focuses on the early impact response of textile armour systems. A relatively new data acquisition system, the Enhanced Laser Velocity Sensor (ELVS), was refined and used to generate a large database of results for a 5.57 mm diameter, 3 gram, non-deforming projectile impacting single-ply configurations of Ballistic Nylon, two weaves of Kevlar 129, and Zylon (PBO) over a range of velocities from 61 m/s to 248 m/s. In addition, one Kevlar 129 material was tested in configurations of 2, 3, 4, 8 and 16 plies over a range of strike velocities from 90 m/s to 481 m/s. ELVS results consisted of high-resolution timehistories of displacement, velocity and energy for each system tested. The strain wave velocity and ballistic performance of each system was also determined. Results taken from during the impact event were analysed up to just prior to the strain-wave rebounding from the boundary and returning to the impact point---effectively removing boundary influences. Regardless of system type, a constant rate of energy absorption within the pre-rebound timeframe was found to exist, which scales with the strike velocity to approximately the 8/3-power. Well-established single fibre theory was modified and applied to woven materials. It was assumed that three primary energy absorption mechanisms exist; elastic strain, in-plane kinetic and out-of-plane kinetic. This simple model yields the experimentally observed 8/3 exponent and parametrically predicts the difference between the different single-ply material systems, but underpredicts the observed behaviour by a factor of 2 and cannot address the performance reduction with increasing ply count. This combined experimental and analytical work confirms the long-held assumption that single fibre wave physics is applicable to multi-ply woven systems. More significantly, for the first time, it decouples material response from overall system response and provides the experimental tools and methodology required to analyse

  16. Developments toward the use of tungsten as armour material in plasma facing components promoted by Euratom-CEA Association

    International Nuclear Information System (INIS)

    Tungsten is increasingly considered as a prime candidate armour material facing the plasma in fusion experiments (ASDEX, JET, ITER). This material is, however, a challenge for the engineers due to its brittleness at room temperature. Its bonding to structural or cooled substrates is a critical issue. The Euratom-CEA Association promotes the development of evolutionary techniques aiming to produce high performance assemblies between tungsten and various substrates. These are 1) functionally graded tungsten to copper, 2) direct electron beam welding of tungsten to Mo-alloy TZM and 3) the characterisation of tungsten coatings deposited on carbon fibre composite by high energy deposition processes. 1) A functionally graded material eliminates the singular point which weakens the heterogeneous assembly, reducing the stresses and allowing a better behaviour. The sintering of submicronic W-Cu powders is investigated. The green shape is processed from W-CuO powder, which is reduced by a hydrogen flow. The compaction and sintering of layers of various compositions (10 to 30 % Cu) produces an assembly (density of ∼ 94%) with a good cohesion. However, the gradient is not effectively controlled, because of the migration of melt copper during the sintering. Future work aims to improve the process by using spark or microwave assisted sintering. 2) Electron beam welding of Mo-alloy TZM is investigated, to produce high temperature components required by radiation cooled PFCs. They require only mechanical properties and no vacuum sealing. The driving line is to use simple tungsten shapes to reduce the milling cost. In spite of low weldable properties of the refractory alloys, a good bonding up to a depth of 5 mm is obtained. Hardness measurements show that the melt area and the heat affected zone are harder than TZM, the weakest materials at 230 Hv. Quench tests in water from up to 2000oC are done without apparent crack formation. 3) Finally, characterisation techniques are

  17. Localization of 18S ribosomal genes in suckermouth armoured catfishes Loricariidae (Teleostei, Siluriformes with discussion on the Ag-NOR evolution

    Directory of Open Access Journals (Sweden)

    Anderson Alves

    2012-09-01

    Full Text Available The family Loricariidae with about 690 species divided into six subfamilies, is one of the world’s largest fish families. Cytogenetic studies conducted in the family showed that among 90 species analyzed the diploid number ranges from 2n=38 in Ancistrus sp. to 2n=96 in Hemipsilichthys gobio Luetken, 1874. In the present study, fluorescence in situ hybridization (FISH was employed to determine the chromosomal localization of the 18S rDNA gene in four suckermouth armoured catfishes: Kronichthys lacerta (Nichols, 1919, Pareiorhaphis splendens (Bizerril, 1995, Liposarcus multiradiatus (Hancock, 1828 and Hypostomus prope plecostomus (Linnaeus, 1758. All species analyzed showed one chromosome pair with 18S rDNA sequences, as observed in the previous Ag-NORs analyses. The presence of size and numerical polymorphism was observed and discussed, with proposing a hypothesis of the Ag-NOR evolution in Loricariidae.

  18. Armouring of well cement in H2S–CO2 saturated brine by calcite coating – Experiments and numerical modelling

    International Nuclear Information System (INIS)

    The active acid gas (H2S–CO2 mixture) injection operations in North America provide practical experience for the operators in charge of industrial scale CO2 geological storage sites. Potential leakage via wells and their environmental impacts make well construction durability an issue for efficiency/safety of gas geological storage. In such operations, the well cement is in contact with reservoir brines and the injected gas, meaning that gas–water–solid chemical reactions may change the physical properties of the cement and its ability to confine the gas downhole. The cement-forming Calcium silicate hydrates carbonation (by CO2) and ferrite sulfidation (by H2S) reactions are expected. The main objective of this study is to determine their consequences on cement mineralogy and transfer ability. Fifteen and 60 days duration batch experiments were performed in which well cement bars were immersed in brine itself caped by a H2S–CO2 phase at 500 bar–120 °C. Scanning electron microscopy including observations/analyses and elemental mapping, mineralogical mapping by micro-Raman spectroscopy, X-ray diffraction and water porosimetry were used to characterize the aged cement. Speciation by micro-Raman spectroscopy of brine trapped within synthetic fluid inclusions were also performed. The expected calcium silicate hydrates carbonation and ferrite sulfidation reactions were evidenced. Furthermore, armouring of the cement through the fast creation of a non-porous calcite coating, global porosity decrease of the cement (clogging) and mineral assemblage conservation were demonstrated. The low W/R ratio of the experimental system (allowing the cement to buffer the interstitial and external solution pH at basic values) and mixed species diffusion and chemical reactions are proposed to explain these features. This interpretation is confirmed by reactive transport modelling performed with the HYTEC code. The observed cement armouring, clogging and mineral assemblage

  19. Study for Key Technology of Light Kevlar Non-Woof Cloth Body Armour%轻质芳纶无纬布防弹衣关键技术研究

    Institute of Scientific and Technical Information of China (English)

    吴中伟; 刘元坤; 常浩

    2014-01-01

    本研究采用单因素实验设计的方法,以及采用添加压敏胶粘剂及固化剂的方法,研究了一种新型防凹陷芳纶无纬布。该无纬布无需进行二次上胶即可压制成防凹陷材料,并通过对防凹陷材料结构设计、压制工艺的优化,开发出了一种轻薄、穿着舒适的防弹衣产品。与传统的防弹衣产品相比,该结构防弹衣产品防弹性能达到NIJ IIIA级要求,防凹陷材料制备的防弹芯片面密度更低,产品重量降低了20%以上,产品的厚度由12mm减少至5.5mm,可明显减轻作战人员的负荷,芯片结构更加隐形,穿着更加舒适,满足了目前市场的发展需求。%In this study, a novel preventing depression of aramid non-woof cloth was prepared by adding pressure-sensitive adhesives and curing agent based on single factor experimental design methods. This non-woof cloth can be pressed into preventing depression materials without the secondary using adhesive. And a lightweight and comfortable body armour was developed by structural design of preventing depression material and optimization of pressing process. Compared to traditional body armour, the product could reach NIJ IIIA level requirements, and had the lower the density of the bullet-proof chip. The weight of product was decreased by more than 20%, and the thickness of product was reduced from 12mm to 5.5mm. These can significantly reduce the load, meanwhile, chip structure was more invisible and wearing more comfortable, these could meet current market trends.

  20. Material, Structural Design of Armour Units

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    Stone and concrete are two materials generally used for the construction of rubble mound breakwaters. This paper deals with concrete only.......Stone and concrete are two materials generally used for the construction of rubble mound breakwaters. This paper deals with concrete only....

  1. The Armour of Hope and other works

    OpenAIRE

    Just, Kate

    2013-01-01

    The series of work entitled The Skin of Hope was produced during a 2012 Australia Council for the Arts studio residency in Barcelona, where I was accompanied by my partner Paula and our adopted daughter, Hope. Blurring the usual divide between familial life and art practice, the residency inspired a series of hand knitted sculptures and photographs weaving an account of the ways that Hope and I acknowledge, bond and imprint each other at skin level. Materialising our past wounds and present, ...

  2. Armour Protection and Affordable Protection for Futuristic Combat Vehicles

    OpenAIRE

    V. Madhu; T. Balakrishna Bhat

    2011-01-01

    Protection creates a shift in the internal paradigm of the soldier and leads to multiplied psychological stamina for moving fearlessly in the battlefield which generates a major force-multiplier effect. Hence, the mechanized forces are still likely to be one of the dominant forces on the futuristic battlefield and would be the primary target of enemy forces capable of engaging from tank guns up to 4-5 km in a direct fire mode and up to 8-10 km in an indirect fire modes. Increased protection i...

  3. The Use of Gabbro Rock Armour in Rubble Mound Structures

    DEFF Research Database (Denmark)

    Beck, J. Blow; Burcharth, H. F.; Danielsen, S. W.;

    2000-01-01

    offer. In order to exploit the advantages of Gabbro, Franzefoss Bruk, Norway; Havnecon Consulting Aps and the Aalborg University, Denmark have entered a co-operation on the development of a Gabbro rubble mound breakwater. This paper describes the development of the project and explains the savings...

  4. A Silurian armoured aplacophoran and implications for molluscan phylogeny.

    Science.gov (United States)

    Sutton, Mark D; Briggs, Derek E G; Siveter, David J; Siveter, Derek J; Sigwart, Julia D

    2012-10-01

    The Mollusca is one of the most diverse, important and well-studied invertebrate phyla; however, relationships among major molluscan taxa have long been a subject of controversy. In particular, the position of the shell-less vermiform Aplacophora and its relationship to the better-known Polyplacophora (chitons) have been problematic: Aplacophora has been treated as a paraphyletic or monophyletic group at the base of the Mollusca, proximate to other derived clades such as Cephalopoda, or as sister group to the Polyplacophora, forming the clade Aculifera. Resolution of this debate is required to allow the evolutionary origins of Mollusca to be reconstructed with confidence. Recent fossil finds support the Aculifera hypothesis, demonstrating that the Palaeozoic-era palaeoloricate 'chitons' included taxa combining certain polyplacophoran and aplacophoran characteristics. However, fossils combining an unambiguously aplacophoran-like body with chiton-like valves have remained elusive. Here we describe such a fossil, Kulindroplax perissokomos gen. et sp. nov., from the Herefordshire Lagerstätte (about 425 million years bp), a Silurian deposit preserving a marine biota in unusual three-dimensional detail. The specimen is reconstructed three-dimensionally through physical-optical tomography. Phylogenetic analysis indicates that this and many other palaeoloricate chitons are crown-group aplacophorans. PMID:23038472

  5. The design of mosaic armour: The influence of tile size on ballistic performance

    OpenAIRE

    Hazell, P.J.; Roberson, C. J.; Moutinho, M.

    2008-01-01

    Silicon carbide square tiles of different areal geometries and manufactured via two different processing routes have been bonded to polycarbonate layers to evaluate their ballistic performance. Four ceramic tile sizes were tested: 85 mm, 60 mm, 50 mm and 33 mm. In each case the residual depth-of-penetration into a polycarbonate semi-infinite backing was recorded. To elucidate the penetration and failure mechanisms, a computational model using the JH-1 ceramic model [Holmquis...

  6. The hydraulic performance and structural integrity of A-Jack armour layer

    Institute of Scientific and Technical Information of China (English)

    William G.McDougal

    2010-01-01

    A-Jacks are concrete armor units that are used in both open channel and coastal applications.In open channel applications,they are used for bank and toe protection,flow and grade control,bridge pier scour protection,energy dissipation,and habitat.These small units may be fabricated in standard block machines.In coastal applications,A-Jacks are used in breakwaters,jetties,revetments,and habitat development.Coastal units are generally much larger and more robust than the small open channel units.This paper focuses on coastal applications and in particular,combines results on three topics: (1) recent hydraulic model studies, (2) ahemative fabrication methods,and(3) bundle placement construction methods.Hydraulic models studies were conducted that examined the standard random and uniform placement methods, and also the bundle placement method.In bundle placement, 3~20 A-Jacks are banded together,lifted with a spreader bar, and placed as a single crone pick.This significantly decreases installation time during construction.It also provides a more hydraulically stable placement technique.The hydraulic model tests examined the bundle stability fn random waves for cases where the binding remains in tack and is removed.The geometry of A-Jacks enables a variety of fabrication techniques.One option is to fabricate the A-Jacks as two pieces using flat forms and then grout the two pieces together.Flat forms may be used in conventional block machines for A-Jacks sizes up to 1.3 re.Larger sizes may be wet cast in flat forms or gang forms.The A-Jacks geometry has been recently modified to increase grouting efficient and strength.Large A-Jacks may also be east in a single piece using "clam shell" type forms.

  7. Armoured spiderman: morphological and behavioural adaptations of a specialised araneophagous predator (Araneae: Palpimanidae)

    Czech Academy of Sciences Publication Activity Database

    Pekár, S.; Šobotník, Jan; Lubin, Y.

    2011-01-01

    Roč. 98, č. 7 (2011), s. 593-603. ISSN 0028-1042 Institutional research plan: CEZ:AV0Z40550506 Keywords : prey specificity * stenophagy * predatory behaviour * trophic niche * spider Subject RIV: CC - Organic Chemistry Impact factor: 2.278, year: 2011

  8. Armouring facility? Nuclear-weapon and reactor reseach at the Kaiser-Wilhelm Institute for Physics

    International Nuclear Information System (INIS)

    The Kaiser Wilhelm Institute for Physics is best known as the place where Werner Heisenberg worked on nuclear weapons for Hitler. Although this is essentially true, there is more to the story. At the start of World War II this institute was taken over by the German Army Ordnance to be the central, but not exclusive site for a research project into the economic and military applications of nuclear fission. The Army physicist Kurt Diebner was installed in the institute as its commissarial director. Heisenberg was affiliated with the institute as an advisor at first, and became the director in 1942. Heisenberg and his colleagues, including in particular Karl-Heinz Hoecker, Carl Friedrich von Weizsaecker, and Karl Wirtz, worked on nuclear reactors and isotope separation with the clear knowledge that these were two different paths to atomic bombs [Atombomben]. However, they were clearly ambivalent about what they were doing. New documents recently returned from Russian archives shed new light on this work and the scientists' motivations. (orig.)

  9. Core reilforced braided composite armour as a substitute to steel in concrete reinforcement

    OpenAIRE

    Fangueiro, Raúl; Sousa, Guilherme José Miranda de; Araújo, Mário Duarte de; Pereira, C. Gonilho; Jalali, Said

    2006-01-01

    This paper presents the work that is being done at the University of Minho concerning the development of brainded rods concrete reinforcement. Several samples of core reinforced braided fabrics have been produced varying the type of braided fabric (core reinforced and hybrid), the linear density of the core reinforcing yarns and the type of braiding structure (with or without ribs). The tensile properties of braided fabrics has also been analysed. Core reinforced braided composites rods were ...

  10. Plasma Wall Interaction Phenomena on Tungsten Armour Materials for Fusion Applications

    International Nuclear Information System (INIS)

    One of the most attractive future complements to present energy sources is nuclear fusion. A large progress was made throughout the last decade from both the physical as the technological area leading to the construction of the ITER machine. One of the key issues that recently received a large interest at international level is focused on the Plasma Wall Interaction (PWI). One of the promising Plasma Facing Materials (PFM) are Tungsten (W) and Tungsten alloys. However, despite the worldwide use and industrial availability of W, the database of physical and mechanical properties is very limited. Especially after fusion relevant neutron irradiation and PWI phenomena, most of the properties are still unknown. The plasma fuel consists out of deuterium (D) and tritium (T). Tritium is radio-active and therefore an issue from the safety point of view. During steady-state plasma operation of future fusion power plants, the PFM need to extract a power density of ∼10-20 MW/m2. On top of this heat, transient events will deposit an additional non-negligible amount of energy (Disruptions, Vertical Displacement Events, Edge Localized Modes) during short durations. These severe heat loads cause cracking and even melting of the surface resulting in a reduced lifetime and the creation of dust. A contribution to the understanding of cracking phenomena under the severe thermal loads is described as well as the properties degradation under neutron irradiation. Several W grades were irradiated in the BR2 reactor (SCK.CEN) and the thermal loads were simulated with the electron-beam facility JUDITH (FZJ). Since knowledge should be gained about the Tritium retention in the PFM for safety and licensing reasons, a unique test facility at SCK.CEN is being set-up. The plasmatron VISION-I will simulate steady state plasmas for Tritium retention studies. The formation of surface cracks and dust, the initial porosity, neutron induced traps, re-deposited material - change the Tritium retention in the material in a drastic way. Therefore the PWI (heat loads, erosion, deposition) and consequently the Tritium retention for the various damaged W materials are strongly interconnected (mixing of materials, crack formation, melting, etc.). This paper deals with an approach of the study of these complex and interrelated phenomena. (authors)

  11. Sinking of armour layer around a vertical cylinder exposed to waves and current

    DEFF Research Database (Denmark)

    Nielsen, Anders Wedel; Probst, Thomas; Petersen, Thor Ugelvig;

    2015-01-01

    The mechanisms of the sinking of a scour protection adjacent to a monopile are described in this paper, together with the determination of the equilibrium sinking depth in various wave and combined wave and current conditions based on physical model tests.Sinking of the rocks may ultimately lead ...

  12. The manufacture of carbon armoured plasma-facing components for fusion devices

    International Nuclear Information System (INIS)

    Within the last decade Plansee has been active in the development and manufacture of different plasma-facing-components for nuclear fusion experiments consisting in a tungsten or CFC-armor joined onto metallic substrates like TZM, stainless steel or copper-alloys. The manufacture of these components requires unique joining technologies in order to obtain reliable thermo mechanical stable joints able to withstand highest heat fluxes without any deterioration of the joint. In an overview the different techniques will be presented by some examples of components already manufactured and successfully tested under high heat flux conditions. Furthermore an overview will be given on the manufacture of different high heat flux components for TORE SUPRA, Wendelstein 7-X and ITER. (author)

  13. Interspecific competition, predation, and the coexistence of three closely related neotropical armoured catfishes (Siluriformes-Callichthyidae).

    NARCIS (Netherlands)

    Mol, J.H.A.

    1995-01-01

    Tropical ecosystems are renowned for their high biodiversity with many closely related species living together. Alpha diversity of tropical freshwater fishes is also extremely high, as exemplified by the cichlid fauna of the Great African lakes and the neotropical characins. Since Hutchinson in 1959

  14. Plasma Wall Interaction Phenomena on Tungsten Armour Materials for Fusion Applications

    Energy Technology Data Exchange (ETDEWEB)

    Uytdenhouwen, I. [SCK.CEN - The Belgian Nuclear Research Centre, Institute for Nuclear Materials Science, Boeretang 200, 2400 Mol (Belgium); Forschungszentrum Juelich GmbH, EURATOM-association, D-52425 Juelich (Germany); Department of Applied Physics, Ghent University, Rozier 44, 9000 Ghent (Belgium); Massaut, V. [Department of Applied Physics, Ghent University, Rozier 44, 9000 Ghent (Belgium); Linke, J. [Forschungszentrum Juelich GmbH, EURATOM-association, D-52425 Juelich (Germany); Van Oost, G. [Department of Applied Physics, Ghent University, Rozier 44, 9000 Ghent (Belgium)

    2008-07-01

    One of the most attractive future complements to present energy sources is nuclear fusion. A large progress was made throughout the last decade from both the physical as the technological area leading to the construction of the ITER machine. One of the key issues that recently received a large interest at international level is focused on the Plasma Wall Interaction (PWI). One of the promising Plasma Facing Materials (PFM) are Tungsten (W) and Tungsten alloys. However, despite the worldwide use and industrial availability of W, the database of physical and mechanical properties is very limited. Especially after fusion relevant neutron irradiation and PWI phenomena, most of the properties are still unknown. The plasma fuel consists out of deuterium (D) and tritium (T). Tritium is radio-active and therefore an issue from the safety point of view. During steady-state plasma operation of future fusion power plants, the PFM need to extract a power density of {approx}10-20 MW/m{sup 2}. On top of this heat, transient events will deposit an additional non-negligible amount of energy (Disruptions, Vertical Displacement Events, Edge Localized Modes) during short durations. These severe heat loads cause cracking and even melting of the surface resulting in a reduced lifetime and the creation of dust. A contribution to the understanding of cracking phenomena under the severe thermal loads is described as well as the properties degradation under neutron irradiation. Several W grades were irradiated in the BR2 reactor (SCK.CEN) and the thermal loads were simulated with the electron-beam facility JUDITH (FZJ). Since knowledge should be gained about the Tritium retention in the PFM for safety and licensing reasons, a unique test facility at SCK.CEN is being set-up. The plasmatron VISION-I will simulate steady state plasmas for Tritium retention studies. The formation of surface cracks and dust, the initial porosity, neutron induced traps, re-deposited material - change the Tritium retention in the material in a drastic way. Therefore the PWI (heat loads, erosion, deposition) and consequently the Tritium retention for the various damaged W materials are strongly interconnected (mixing of materials, crack formation, melting, etc.). This paper deals with an approach of the study of these complex and interrelated phenomena. (authors)

  15. Strong Cryptography Armoured Computer Viruses Forbidding Code Analysis: the bradley virus

    OpenAIRE

    Filiol, Eric

    2004-01-01

    Imagining what the nature of future viral attacks might look like is the key to successfully protecting against them. This paper discusses how cryptography and key management techniques may definitively checkmate antiviral analysis and mechanisms. We present a generic virus, denoted bradley which protects its code with a very secure, ultra-fast symmetric encryption. Since the main drawback of using encryption in that case lies on the existence of the secret key or information about it within ...

  16. RHINO: armoured plated networking with intelligent high speed wireless ad hoc capability

    Science.gov (United States)

    Markarian, Garik; Singh, Farid

    2008-04-01

    This paper describes the concept of an intelligent high speed wireless ad-hoc network, which is currently being developed. The technology aims at, not replacing any of the existing standards, but aims to complement them in urban, military and hazardous environments. Known as Rhino, the technology is a platform independent, IP based network which will provide adequate bandwidth for real time video, audio and data traffic. The technology and specifications described in this paper are based on initial development of the technology.

  17. Viability Study of Concept of Hybrid Antitank & Air Defence Armoured Vehicle.

    Directory of Open Access Journals (Sweden)

    Mohan Vizhakat

    2000-07-01

    Full Text Available In the past few decades, tanks have been developed into a highly effective weapon system, particularly useful in the shortj intense and highly dynamic scenario of modem warfare. However, with the advent of new jtechnology, tanks would definitely have to undergo improvements to remain cost-effective as well as combat-effective. Such evolutionjis already taking place with new designs being developed 31" well as those still on the drawing board of advanced nations. In the race for technolological domilnation, only those nations with a tradition of indigenous innovations and courage to tread new paths, can hope to remain dominant in the field of military technology.

  18. Flower Power: The Armoured Expert in the CanMEDS Competency Framework?

    Science.gov (United States)

    Whitehead, Cynthia R.; Austin, Zubin; Hodges, Brian D.

    2011-01-01

    Competency frameworks based on roles definitions are currently being used extensively in health professions education internationally. One of the most successful and widely used models is the CanMEDS Roles Framework. The medical literature has raised questions about both the theoretical underpinnings and the practical application of outcomes-based…

  19. Simulation of tokamak armour erosion and plasma contamination at intense transient heat fluxes in ITER

    International Nuclear Information System (INIS)

    For ITER, the potential material damage of plasma facing tungsten-, CFC-, or beryllium components during transient processes such as ELMs or mitigated disruptions are simulated numerically using the MHD code FOREV-2D and the melt motion code MEMOS-1.5D for a heat deposition in the range of 0.5-3 MJ/m2 on the time scale of 0.1-1 ms. Such loads can cause significant evaporation at the target surface and a contamination of the SOL by the ions of evaporated material. Results are presented on carbon plasma dynamics in toroidal geometry and on radiation fluxes from the SOL carbon ions obtained with FOREV-2D. The validation of MEMOS-1.5D against the plasma gun tokamak simulators MK-200UG and QSPA-Kh50, based on the tungsten melting threshold, is described. Simulations with MEMOS-1.5D for a beryllium first wall that provide important details about the melt motion dynamics and typical features of the damage are reported

  20. 下马“微”UNDER ARMOUR MICRO G SERIES

    Institute of Scientific and Technical Information of China (English)

    207ers

    2010-01-01

    创立于1996年的UNDER ARMOUR公司此前给人留下最深印象的就是其运动内衣产品,这种率先在橄榄球领域推广的紧身功能面料内衣不仅令其成为2003年后发展最快的运动品牌,更引领了一场席卷全行业的运动内衣潮流。然而,随着NIKE、ADIDAS等“大鳄”品牌先后推出运动内衣产品,UA如果只是死守其优势市场,势必愈发陷入被动,

  1. Sinking of armour layer around a cylinder exposed to a current

    DEFF Research Database (Denmark)

    Nielsen, Anders Wedel; Sumer, B. Mutlu; Fredsøe, Jørgen; Christensen, Erik Damgaard

    2011-01-01

    The flow processes in a scour protection around a monopile in steady current are described in relation to transport of sediment in the scour protection based on physical model tests. The scour protection consisted of uniformly distributed coarse stones without filter layer. Transport of sediment ...

  2. Enhancement of wear and ballistic resistance of armour grade AA7075 aluminium alloy using friction stir processing

    OpenAIRE

    I. Sudhakar; V. Madhu; G. Madhusudhan Reddy; K. Srinivasa Rao

    2015-01-01

    Industrial applications of aluminium and its alloys are restricted because of their poor tribological properties. Thermal spraying, laser surfacing, electron beam welding are the most widely used techniques to alter the surface morphology of base metal. Preliminary studies reveal that the coating and layering of aluminium alloys with ceramic particles enhance the ballistic resistance. Furthermore, among aluminium alloys, 7075 aluminium alloy exhibits high strength which can be compared to tha...

  3. On Methods of Establishing Design Diagrams for Structural Integrity of Slender Complex Types of Breakwater Armour Units

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Howell, Gary J.

    1988-01-01

    application of the method based on the results obtained from the extensive prototype research program with 42 t Dolosse at Crescent City performed by the U.S. Army Corps of Engineers WES Vicksburg (Howell 1986). The reason for and the object of this early presentation of the method is that, if accepted by...... units to measure bending movements in a cross section of the units and the accelerations (impact speed) were first used by DHL in 1980. Recent developments were presented by Scott et al. 1986. Correct scaling of the most important material properties of concrete in small scale hydraulic model tests was...... because the first mentioned method is related only to impact dominated units and the other methods have been used only for checking specific designs and not yet for the development or support of general design methods.Consequently there is a need for an approach by which more general information and...

  4. Experimental and numerical investigation on under-water friction stir welding of armour grade AA2519-T87 aluminium alloy

    OpenAIRE

    S. Sree Sabari; S. Malarvizhi; V. Balasubramanian; G. Madusudhan Reddy

    2016-01-01

    Friction stir welding (FSW) is a promising welding process that can join age hardenable aluminium alloys with high joint efficiency. However, the thermal cycles experienced by the material to be joined during FSW resulted in the deterioration of mechanical properties due to the coarsening and dissolution of strengthening precipitates in the thermo-mechanical affected zone (TMAZ) and heat affected zone (HAZ). Under water friction stir welding (UWFSW) is a variant of FSW process which can maint...

  5. Experimental and numerical investigation on under-water friction stir welding of armour grade AA2519-T87 aluminium alloy

    Directory of Open Access Journals (Sweden)

    S. Sree Sabari

    2016-08-01

    Full Text Available Friction stir welding (FSW is a promising welding process that can join age hardenable aluminium alloys with high joint efficiency. However, the thermal cycles experienced by the material to be joined during FSW resulted in the deterioration of mechanical properties due to the coarsening and dissolution of strengthening precipitates in the thermo-mechanical affected zone (TMAZ and heat affected zone (HAZ. Under water friction stir welding (UWFSW is a variant of FSW process which can maintain low heat input as well as constant heat input along the weld line. The heat conduction and dissipation during UWFSW controls the width of TMAZ and HAZ and also improves the joint properties. In this investigation, an attempt has been made to evaluate the mechanical properties and microstructural characteristics of AA2519-T87 aluminium alloy joints made by FSW and UWFSW processes. Finite element analysis has been used to estimate the temperature distribution and width of TMAZ region in both the joints and the results have been compared with experimental results and subsequently correlated with mechanical properties.

  6. On the Influence of Fracture Criterion on Perforation of High-Strength Steel Plates Subjected to Armour Piercing Projectile

    Directory of Open Access Journals (Sweden)

    Tria Djalel Eddine

    2015-06-01

    Full Text Available Artykuł przedstawia numeryczne badania wpływu kryterium pekania materiału na perforacje płyt ze stali pancernej 30PM pociskiem przeciwpancernym 7,6251 mm. Dokonano oceny czterech modeli pekania materiałów plastycznych w celu wyboru najbardziej odpowiedniego z nich. W artykule wykorzystano zmodyfikowany model konstytutywny Johnsona-Cooka (MJC sprzezony z jednym czterech kryteriów pekania: kryterium MJC, kryterium Cockrofta-Lathama (CL, kryterium maksymalnego naprezenia stycznego i kryterium stałego granicznego odkształcenia. Zastosowano trójwymiarowy algorytm w opisie Lagrange’a, zawierajacy zarówno skonczone elementy jak i czastki, z automatyczna konwersja zniekształconych elementów w bezsiatkowe czastki. Wyniki symulacji numerycznej oceniono na postawie porównania z wynikami doswiadczen. Model pekania MJC, sformułowany w przestrzeni trójosiowosci naprezenia i równowaznego odkształcenia plastycznego, pozwolił przewidziec realistycznie obraz pekania materiału i wartosci predkosci resztkowych pocisków. Jednakze wyniki badan wykazały, ze równiez jednoparametrowy model CL, dla którego kalibracji wystarczy jeden prosty test materiałowy, daje porównywalne wyniki z kryterium MJC. Stwierdzono, ze kryterium maksymalnego naprezenia stycznego niepoprawnie opisuje proces tworzenia sie korka. Równiez kryterium stałej wartosci odkształcenia granicznego nie moze byc uzyte do scharakteryzowania procesu niszczenia materiału.

  7. Future Operational Scenario for Antitank Guided Missile Systems

    Directory of Open Access Journals (Sweden)

    A.P.J. Abdul Kalam

    1995-07-01

    Full Text Available Discusses latest type of explosive reactive armour (ERA and active armour for defeating ERA that contains a slab of relatively less sensitive explosive sandwiched between two metal plates and attached to the main armour to be protected.

  8. Armouring facility? Nuclear-weapon and reactor reseach at the Kaiser-Wilhelm Institute for Physics; Eine Waffenschmiede? Kernwaffen- und Reaktorforschung am Kaiser-Wilhelm-Institut fuer Physik

    Energy Technology Data Exchange (ETDEWEB)

    Hachtmann, R. (ed.); Walker, M.

    2005-07-01

    The Kaiser Wilhelm Institute for Physics is best known as the place where Werner Heisenberg worked on nuclear weapons for Hitler. Although this is essentially true, there is more to the story. At the start of World War II this institute was taken over by the German Army Ordnance to be the central, but not exclusive site for a research project into the economic and military applications of nuclear fission. The Army physicist Kurt Diebner was installed in the institute as its commissarial director. Heisenberg was affiliated with the institute as an advisor at first, and became the director in 1942. Heisenberg and his colleagues, including in particular Karl-Heinz Hoecker, Carl Friedrich von Weizsaecker, and Karl Wirtz, worked on nuclear reactors and isotope separation with the clear knowledge that these were two different paths to atomic bombs [Atombomben]. However, they were clearly ambivalent about what they were doing. New documents recently returned from Russian archives shed new light on this work and the scientists' motivations. (orig.)

  9. Steady State Modelling of Three-core Wire Armoured Submarine Cables: Power losses and Ampacity Estimation based on FEM and IEC

    DEFF Research Database (Denmark)

    Baù, Matteo; Viafora, Nicola; Hansen, Chris Skovgaard;

    2016-01-01

    in a comparative study with the IEC 60287 Standard, developed in terms of power losses, loss factors and cable ampacity. Despite the model limitations, the estimated loss factors are mainly in compliance with the state of the art, verifying the widely recognized conservatism of the IEC standard...

  10. Seahorses under a changing ocean: the impact of warming and acidification on the behaviour and physiology of a poor-swimming bony-armoured fish.

    Science.gov (United States)

    Faleiro, Filipa; Baptista, Miguel; Santos, Catarina; Aurélio, Maria L; Pimentel, Marta; Pegado, Maria Rita; Paula, José Ricardo; Calado, Ricardo; Repolho, Tiago; Rosa, Rui

    2015-01-01

    Seahorses are currently facing great challenges in the wild, including habitat degradation and overexploitation, and how they will endure additional stress from rapid climate change has yet to be determined. Unlike most fishes, the poor swimming skills of seahorses, along with the ecological and biological constraints of their unique lifestyle, place great weight on their physiological ability to cope with climate changes. In the present study, we evaluate the effects of ocean warming (+4°C) and acidification (ΔpH = -0.5 units) on the physiological and behavioural ecology of adult temperate seahorses, Hippocampus guttulatus. Adult seahorses were found to be relatively well prepared to face future changes in ocean temperature, but not the combined effect of warming and acidification. Seahorse metabolism increased normally with warming, and behavioural and feeding responses were not significantly affected. However, during hypercapnia the seahorses exhibited signs of lethargy (i.e. reduced activity levels) combined with a reduction of feeding and ventilation rates. Nonetheless, metabolic rates were not significantly affected. Future ocean changes, particularly ocean acidification, may further threaten seahorse conservation, turning these charismatic fishes into important flagship species for global climate change issues. PMID:27293694

  11. Stability of Dolos Slopes

    DEFF Research Database (Denmark)

    Brorsen, Michael; Burcharth, Hans F.; Larsen, Torben

    The stability of dolos armour blocks against wave attack has been investigated in wave model studies.......The stability of dolos armour blocks against wave attack has been investigated in wave model studies....

  12. Long bone histology and microanatomy of Placodontia (Diapsida: Sauropterygia)

    NARCIS (Netherlands)

    Klein, N.; Houssaye, A.; Neenan, J.M.; Scheyer, T.M.

    2015-01-01

    Placodontia, an enigmatic group of durophagous and in part heavily armoured animals, were members of Sauropterygia, the most diverse and successful group of Mesozoic marine reptiles. Microanatomy and histology of long bones of several armoured and non-armoured Placodontia were studied, covering most

  13. 枪弹射击致防弹衣后长白猪远达脑组织损伤特点及其机制%Characteristics and mechanism of behind armour blunt trauma in Landrace brain

    Institute of Scientific and Technical Information of China (English)

    苏正林; 许民辉; 赖西南; 张波; 黄艺峰; 王丽丽

    2011-01-01

    Objective To study the characteristics of behind armor blunt trauma extending to the brain and to investigate the biomechanics mechanism of the remote injury. Methods Eighteen male Landraces were randomly divided into a sham injury group (n =4) , a bullet velocity 910 m/s group (re =6), a 740 m/s group (n =4) and a S90 m/s group (n =4). The injury model was anesthetized Landrace in right lateral position and wrapped in a two-layer bullet-proof vest. The outer layer was ceramic hard armor with NIJ Ⅲ protection grade. The inner layer was police grade II ultra-high molecular polyethylene soft body armor. Caliber 5. 8 mm ballistic guns were fired at 25 m range and three different projectile velocities, aimed at the left midclavicular line 4, 5 intercostal (heart window). Air bomb shooting was applied to sham injury group. EEG, ECG, invasive arterial blood pressure, heart rate and respiratory changes before and after injury were continuously monitored. Plasma was collected at 1, 2 and 3 h before and after injury to detect markers of brain injury. Lumbar puncture was taken at 3 h before and after injury to test specific brain injury protein in cerebrospinal fluid. In 3 h after injury the animals were deep anesthetized and bled to death. Their brain blocks were collected for toluidine blue staining and electron microscopy. The other 4 Landrace pigs were used for biomechanical testing. On the basis of the above model pressure sensors were placed in the subcutaneous layer of precordium at the point of impact, pericardial cavity, left chest, left common carotid artery and cranial cavity. Acceleration sensors and force sensors were placed in the sixth rib at precordial midclavicular line. When the target was hit, each parts biomechanical parameters and duration were recorded and analyzed. Results In the 3 groups of different speed, spectrum intensity of low-frequency EEG Delta and Theta wave within 2 minutes after injury was significantly lower than that before injury (P <0. 05) , and the decline was about 10%. In 5 min after injury the amplitude was restored to pre-injury level. There was no significant difference among 3 speed groups (P>0.05). Three hours after injury, acute injury alterations were found in Nissl stained hippocampal under light microscope. The 910 m/s group had hippocampal neurons atrophy and varying sizes of nuclei; the 740 m/s group had neurons atrophy and nucleus deviation; the 590 m/s group had mild neuron swelling, injury scale 910 m/s group>740 m/s group>590 m/s group> sham injury group. When bullets hit precordial vest at three different speed, pressures in pericardial cavity, chest cavity, internal carotid artery and cranial cavity instantly surged, to 23.32 ±4.41 kPa in 590 m/s group, 45.52 ±27.38 kPa in 740 m/s group, and 88.27 ± 8. 81 kPa in 910 m/s group. Each group's pressure was significantly different from that of the other two groups (P<0. 01). Conclusion Under the protection of NIJ Ⅲ grade outer layer and police II grade inner layer, as the bullet speed increases, the Landrace has central nervous EEG suppression, central neuron degeneration and demyelination in hippocampus, which may produce early symptoms and late effects. Biomechanical testing suggests that under hard armor protection, high-speed bullet hitting Landrace precordial bulletproof plate causes a small displacement of the animal and kinetic energy of the bullet instantly decreased from extremely high to 0. The energy passes to the organism through body armor deformation. It could reach remote central nervous system through pulmonary hollow organs, heart impact and bone transfer, and this may be the reason for remote injury.%目的 观察防弹衣后远达脑组织的损伤特点及探讨损伤的生物力学机制.方法 18只雄性长白猪分成假致伤组(n=4),子弹速度910 m/s组(n=6),740 m/s组(n=4)和590 m/s组(n=4).致伤模型为麻醉后长白猪右侧卧位,胸前包裹外层为防护等级NIJⅢ级陶瓷硬式防弹衣,内层为警用Ⅱ级超高分子聚乙烯软式防弹衣,小口径弹道枪以25 m射距、3种不同弹速瞄准左锁骨中线4、5肋间(心脏窗)射击,假致伤组行空爆弹射击.持续监测致伤前后脑电图、心电图、有创动脉血压、心率、呼吸变化.取伤前,伤后1、2、3h血浆进行脑损伤标志物检测,伤前及伤后3h脑脊液进行特异性脑损伤蛋白检测.伤后3h深麻醉后放血处死动物,取脑组织进行病理检查.另取4只雄性长白猪行生物力学测试,在上述模型基础上于弹着点心前区皮下、心包腔、左侧胸腔、左侧颈总动脉及颅内布放压力传感器,心前区锁骨中线第6肋骨布放加速度传感器及力传感器,测试命中时各部位生物力学参数及持续时间,进行分析.结果 3种不同速度组致伤后2 min内脑电图低频Delta、Theta波定量分析频谱强度幅值与致伤前比较明显降低(P<0.05),降幅约10%,伤后5 min后回升恢复到伤前水平,3种速度组间无显著差异(P>0.05).伤后3h光镜下尼氏染色海马存在急性损伤改变,910 m/s组海马神经元胞体萎缩,细胞核大小不等;740 m/s组神经元胞体萎缩,细胞核偏位;590 m/s组神经元轻度肿胀,损伤分级910 m/s组>740 m/s组>590 m/s组>假致伤组.3种速度子弹击中心前区防弹衣时心包腔、胸腔、颈内动脉及颅内压力瞬间急速上升,590 m/s组(23.32±4.41 )kPa,740 m/s组(45.52±27.38) kPa,910 m/s组(88.27±8.81) kPa,两两比较3组压力有显著差异(P<0.01).在外层NIJⅢ内层为警用Ⅱ级防护下,随着子弹速度的增加,长白猪出现中枢神经脑电抑制,在海马区出现中枢神经元变性、脱髓鞘改变,可能产生早期症状及中晚期效应.生物力学检测提示在硬质防弹衣防护下,子弹高速打击长白猪心前区防弹板,使动物产生了较小的位移,瞬间子弹动能由极高降为0.结论子弹制动所释放出的能量通过防弹衣的变形传递给生物体,通过对空腔脏器(肺脏、心脏)冲击及通过骨性传递可以到达远端中枢神经,可能是产生远达损伤的原因.

  14. Danida3

    DEFF Research Database (Denmark)

    Henriksen, Mogens

    1996-01-01

    At the request of Danish Ministry of Foreign Affairs, Department TSA.4, electrical testing of possibly damaged cables has been evaluated. This matter concerns three different types of cable, which are,10 km 30(36) kV XLPE armoured submarine power cable, 1-phase15 km 30(36) kV XLPE armoured underg...... underground power cable, 1-phase20 km 10(12) kV XLPE armoured underground power cable, 3-phase....

  15. Los Robles Breakwater 2D-Tests

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Pedersen, Thomas Schmidt; Andersen, Thomas Lykke

    The present report contains the results of main armour stability and toe stability tests for the Los Robles breakwater in Chile.......The present report contains the results of main armour stability and toe stability tests for the Los Robles breakwater in Chile....

  16. Beryllium assessment and recommendation for application in ITER plasma facing components

    Energy Technology Data Exchange (ETDEWEB)

    Barabash, V.; Tanaka, S.; Matera, R. [ITER Joint Central Team, Muenchen (Germany)

    1998-01-01

    The design status of the ITER Plasma Facing Components (PFC) is presented. The operational conditions of the armour material for the different components are summarized. Beryllium is the reference armour material for the Primary Wall, Baffle and Limiter and the back-up material for the Divertor Dome. The activities on the selection of the Be grades and the joining technologies are reviewed. (author)

  17. Erosion of macrobrush tungsten armor after multiple intense transient events in ITER

    International Nuclear Information System (INIS)

    The tungsten macrobrushes are foreseen as a perspective ITER divertor armour. Macroscopic erosion by melt motion is the dominating damage mechanism for tungsten armour under high heat loads above 1 MJ/m2 slower than 0.1 ms. In the paper further development of the code MEMOS is presented to describe geometric peculiarities of W-macrobrush armour. The modified code MEMOS is validated against experiments on erosion of W-macrobrush armour in the plasma gun QSPA facility for repetitive plasma loads. A rather good agreement in melt layer erosion was demonstrated. For ITER divertor W-macrobrush armour the results of fluid dynamics simulation of the melt motion erosion under giant ELMs are presented. The heat loads as input for MEMOS for particular single ELM are numerically simulated using the two-dimensional MHD code FOREV

  18. Danida1

    DEFF Research Database (Denmark)

    Henriksen, Mogens

    1996-01-01

    At the request of Danish Ministry of Foreign Affairs, Department TSA.4, electrical testing of possibly damaged cables has been evaluated. This matter concerns three different types of cable, which are10 km 30(36) kV XLPE armoured submarine power cable, 1-phase15 km 30(36) kV XLPE armoured...... underground power cable, 1-phase20 km 10(12) kV XLPE armoured underground power cable, 3-phase.The possible damage of said cables took place during shipment from Denmark to Bangladesh....

  19. Design of Linear Wet Clutch Disk of Controlled Soft-start Equipment Used in High Power Armoured Face Conveyor%大功率刮板输送机可控软起动装置线性湿式离合器的设计

    Institute of Scientific and Technical Information of China (English)

    刘伟; 张庚云

    2013-01-01

    分析了CST系统软起动的过程和原理,介绍了线性湿式摩擦离合器的结构组成和工作原理.在此基础上,对线性湿式离合器的各关键参数进行了计算,旨在为大功率刮板输送机可控软起动设备的开发提供理论依据.

  20. Studies on Some Aspects of Propellants for Improving the Performance of Tank Guns

    OpenAIRE

    K. P. Rao; P. K. Umrani; R.G.K. Nair; Venkatesan, K

    1987-01-01

    The main criterion, in the design of propellant charge for a tank gun, is to achieve the highest possible muzzle velocity for fin stabilized armour piercing dicarding sabot (FSAPDS) projectiles. This ensures penetration through the toughest armour plates by the kinetic energy of the projectile. One of the solutions, is to increase the force constant of the propellant. Higher force constant from conventional double and triple base propellant compositions lead to prohibitive linear rates of bur...

  1. Applicability of tungsten/EUROFER blanket module for the DEMO first wall

    International Nuclear Information System (INIS)

    In this paper we analyse a sandwich-type blanket configuration of W/EUROFER for DEMO first wall under steady-state normal operation and off-normal conditions, such as vertical displacements and runaway electrons. The heat deposition and consequent erosion of the tungsten armour is modelled under condition of helium cooling of the first wall blanket module and by taking into account the conversion of the magnetic energy stored in the runaway electron current into heat through the ohmic dissipation of the return current induced in the metallic armour structure. It is shown that under steady-state DEMO operation the first wall sandwich type module will tolerate heat loads up to ∼14 MW/m2. It will also sustain the off-normal events, apart from the hot vertical displacement events, which will melt the tungsten armour surface

  2. Erosion of tungsten armor after multiple intense transient events in ITER

    International Nuclear Information System (INIS)

    Macroscopic erosion by melt motion is the dominating damage mechanism for tungsten armour under high-heat loads with energy deposition W > 1 MJ/m2 and τ > 0.1 ms. For ITER divertor armour the results of a fluid dynamics simulation of the melt motion erosion after repetitive stochastically varying plasma heat loads of consecutive disruptions interspaced by ELMs are presented. The heat loads for particular single transient events are numerically simulated using the two-dimensional MHD code FOREV-2D. The whole melt motion is calculated by the fluid dynamics code MEMOS-1.5D. In addition for the ITER dome melt motion erosion of tungsten armour caused by the lateral radiation impact from the plasma shield at the disruption and ELM heat loads is estimated

  3. An important erosion process on steep burnt hillslopes

    Science.gov (United States)

    Langhans, Christoph; Nyman, Petter; Noske, Philip; Lane, Patrick; Sheridan, Gary

    2016-04-01

    Steep forested hillslopes often display a high degree of armouring where diffusive erosion processes preferentially remove the fine fraction of the surface soil. High infiltration capacities, hydraulic resistance to overland flow and physical anchoring by cover plants and litter mean that even the most extreme rainfall events usually do not erode the armouring substantially. We argue that fire (wild or planned) is essential to the mobilization and transport of the armouring by increasing the rates of overland flow and decreasing trapping opportunities. We present evidence of the types of erosion that lead to the stripping of the surface armouring using post-event surveys and high-rate overland flow experiments. The type of erosion depends on the relative abundance of non-cohesive surface material to overland flow, but we found that a particular type of transport dominates that has no representation in current erosion models: On steep slopes overland flow can lead to incipient motion of individual stones that transfer their momentum to other stones leading to a rapid mobilization of the whole non-cohesive, armoured surface layer. Once in motion, the layer quickly separates out into a granular flow front and liquefied body, akin to debris flows in channels. Depending on the size of the event, these hillslope debris flows (HDF) either get trapped or enter into the channel, stripping the hillslope of most armouring on their way. They provide channels with the material and shear stress needed to erode into the channel bed, increasing the risk of channel debris flows. We present a simple physical model of HDF initiation, movement, and possible re-mobilization on hillslopes that was derived from debris flow theory. Understanding this process, its frequency, and magnitude are important for assessing the role of fire in landscape evolution and risk to humans through debris flow impacts.

  4. Recent Developments in Anti-Tank Ammunition

    Directory of Open Access Journals (Sweden)

    N. S. Venkatesan

    1985-04-01

    Full Text Available Every advance in anti-tank ammunition has been matched by advances in armour material or vice-versa. This applies both to kinetic energy and chemicai energy type of ammunition. Today the kinetic energy ammunition appears to have an upper hand over armour. In t his paper, a brief survey of the modern FSAPDS ammunition, its design aspects and its material technology is made.The capabilities of HEAT type of ammunition are also discussed and the likely trends in ammunition technology are indicated. Some futuristic developments in the field of propulsion are briefly mentioned.

  5. Bitumen Applicator

    OpenAIRE

    Pettersson, Daniel; Lejdeby, Mikael; Zarate, Inigo Oz. de; Delamarliere, Mathieu

    2002-01-01

    This bachelor degree thesis was assigned to us in the fall semester of 2001. The purpose was to redesign a machine for the company Asea Brown Boveri (ABB) in Karlskrona. ABB HVC in Karlskrona is manufacturing high voltage cables. Amongst these the seacables are the largest and most complex. The seacables are heavy naval cables and lies on the bottom of the sea. For these heavy-duty applications the cables need good armouring. The armouring, which is made of steel, needs a corrosion protection...

  6. Gravity-induced encapsulation of liquids by destabilization of granular rafts

    Science.gov (United States)

    Abkarian, Manouk; Protière, Suzie; Aristoff, Jeffrey M.; Stone, Howard A.

    2013-05-01

    Droplets and bubbles coated by a protective armour of particles find numerous applications in encapsulation, stabilization of emulsions and foams, and flotation techniques. Here we study the role of a body force, such as in flotation, as a means of continuous encapsulation by particles. We use dense particles, which self-assemble into rafts, at oil-water interfaces. We show that these rafts can be spontaneously or controllably destabilized into armoured oil-in-water droplets, which highlights a possible role for common granular materials in environmental remediation. We further present a method for continuous production and discuss the generalization of our approach towards colloidal scales.

  7. Armeros milaneses en Navarra: la producción de Eugui

    Directory of Open Access Journals (Sweden)

    Godoy, José A.

    1999-12-01

    Full Text Available In 1595, Philip II summoned a group of Milanese armourers to settle in Eugui (Navarre. Their main work was produced under Philip III. This paper studies these armourers, their trademarks. creations, working conditions and relationships.

    Felipe II ordenó en 1595 el establecimiento en Eugui (Navarra de un grupo de armeros milaneses especializados en el arte de la armadura. Las principales obras se produjeron sin embargo durante el reinado de Felipe III. Se estudia detenidamente la manufactura de Eugui, sus marcas, obras, las circunstancias de sus trabajos y sus relaciones laborales.

  8. L'insémination artificielle intra-utérine, transpéritonéale chez la chèvre: 2. Etude comparative du taux de fécondation après saillie ou insémination artificielle intra-utérine

    OpenAIRE

    Fieni, Francis; Buggin, M.; Tainturier, Daniel; Beckers, Jean-François; Bach-Lijour, B.; Bruyas, J. F.; Daubie, M.

    1990-01-01

    This study was carried out on 570 ovocytes. It shows that goats suprovulated due to FSH treatements of 16 mg Armour given over 3 days (in 8-4-4 mg/day) or 21 mg Armour over 4 days (in 7-6-4-4 mg/day) and undergoing a single intra-uterine transperitoneal insemination under endoscopic control, carried out 46h39 after removing the sponges gives a satisfactory rate of fecondation close to 70%. This rate is a more 15 points lower than that obtained by 2 successive matings 12 hours apart (36 and 24...

  9. Stresses in Dolosse

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Liu, Zhou; Howell, Gary L.;

    1991-01-01

    Failures of rubble mound breakwaters armoured with complex types of unreinforced concrete armour units are often due to breakage. This happens when the stresses exceed the material strength. Sufficient parametric studies of the stresses are not yet available to produce design diagrams for...... structural integrity. The paper presents the results and the analyses of model tests with 200 kg and 200 g load-cell instrumented Dolosse. Static stresses and wave generated stresses were studied as well as model and scale effects. A preliminary design diagram for Dolosse is presented as well....

  10. Preliminary Results of Breakwater Round-Head Tests

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Z.

    1995-01-01

    The rational design diagram for Dolos armour should incorporate both the hydraulic stability and the structural integrity. The previous tests performed by Aalborg University (AU) made available such design diagram for the trunk of Dolos breakwater without superstructures (Burcharth et al. 1992......). Task IBl of rubble mound breakwater failure modes produces such design diagram for the trunk of Dolos breakwater with a superstructure. The objective of the round-head tests is to produce such design diagram for the Dolosse in the round-head. Thus a relatively complete design diagram for Dolos armour...

  11. RETRAINING BY PRIVATE INDUSTRY.

    Science.gov (United States)

    HOOS, IDA R.

    SEVERAL SAN FRANCISCO BAY AREA COMPANIES WERE EXAMINED FOR SPECIFIC PROGRAMS FOR DISPLACED EMPLOYEES. ARMOUR AND COMPANY SOUGHT TO GUIDE DISPLACED EMPLOYEES TO CLASSES OR COURSES OF ACTION OUTSIDE ITS OWN SPHERE OF OPERATION. LOCKHEED HAS PROVIDED UNUSUALLY WELL FOR UPGRADING AND RETRAINING, MAINLY BECAUSE OF INDUSTRY FLUCTUATIONS AND RAPID…

  12. On the defence notion

    CERN Document Server

    Bonfante, Anne

    2007-01-01

    'Trojan horses', 'logic bombs', 'armoured viruses' and 'cryptovirology' are terms recalling war gears. In fact, concepts of attack and defence drive the world of computer virology, which looks like a war universe in an information society. This war has several shapes, from invasions of a network by worms, to military and industrial espionage ...

  13. Millimeter Wave Technology for Armament Applications .

    Directory of Open Access Journals (Sweden)

    A. S. Bains

    1997-10-01

    Full Text Available Use of millimeter wave (MMW technology in armament systems imposes many restrictions on the size, volume and compactness of these systems in addition to ruggedness and reliable functioning in battlefield environment. This paper discusses the related design and technological issues, particularly in, the context of the sensors developed for smart ammunition and active armour protection systems.

  14. Simulation of residual thermostress in tungsten after repetitive ELM-like heat loads

    International Nuclear Information System (INIS)

    Brittle destruction of tungsten armour under action of edge localised modes of plasma instabilities (ELMs) in ITER is an important issue determining the lifetime of the divertor. Besides, cracking of the armour produces tungsten dust with characteristic size of 1-10 μm flying from the armour surface with velocities up to 10 m/s. Influx of the tungsten dust into the ITER confinement decreases the temperature of the plasma, reduces the thermonuclear gain and even may run the confinement into disruption. This paper describes experiments in QSPA-Kh50 plasma gun and modeling, which has been performed for providing more insight into the physics of tungsten cracking under action of ELMs and for confirmation of the important result on stabilization of the crack development at the tungsten armour surface, predicted in our previous paper - the same authors, 2010. The threshold value of energy density deposition for start of tungsten cracking has been measured as 0.3 MJ/m2 after 5-10 shots. From analytical considerations three times smaller threshold value has been predicted with increasing number of shots.

  15. Mutual interactions between P53 and growth factors in cancer

    NARCIS (Netherlands)

    Asschert, JGW; Vellenga, E; De Jong, S; De Vries, EGE

    1998-01-01

    The function of p53 armour suppressor protein is determined by various intrinsic properties of the protein. The effect of p53 DNA-binding, and platein-protein interactions are determined by the conformation of the protein. Thus p53 fulfils its role in cell cycle control and the onset of apoptotic ce

  16. Method to quantify the notional permeability

    NARCIS (Netherlands)

    Verhagen, H.J.; Jumelet, D.; Vilaplana Domingo, A.; Van Broekhoven, P.

    2011-01-01

    In de Van der Meer formulas for armour stability the Notional Permeability is used as a parameter. Unfortunately the physical basis of this parameter is weak. It is therefore suggested to use a relation between the Notional Permeability P and the reduction of wave run-up due to infiltration into the

  17. Design Formula for Breakage of Tetrapods

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Jensen, Jacob Birk; Liu, Z.;

    1995-01-01

    The paper presents a design formula for Tetrapod armour on a 1:1.5 slope exposed to head-on random wave attack. The formula predicts the relative number of broken Tetrapods as function of: the mass of the Tetrapods, the concrete tensile strength and the wave height in front of the structure. Thus...

  18. Stochastic Design of Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Nielsen, Søren R.K.; Burcharth, Hans F.

    The paper presents a level III reliability method from which the armour layer of rubble mound breakwaters can be designed, so that the total costs of construction price and expected maintaince expenses are minimized. Since the physics of the wave-structure interaction are not yet fully understood...

  19. Modelling the Steering Characteristics of Coal Face Conveyors by Random Signal Testing

    OpenAIRE

    Edwards, J. B.; Yazdi, A.M.S.R.

    1983-01-01

    Aquarter scale model of a coal cutting machine and armoured flexible conveyor (a.f.c.) system is subjected to random signal testing in an attempt to fit a continuous elastic beam model to the piecewise rigid a.f.c. structure for vertical steering investigations.

  20. Wave Reflection in 3D Conditions

    DEFF Research Database (Denmark)

    Zanuttigh, Barbara; Andersen, Thomas Lykke

    2010-01-01

    Based on recent experiments carried out in wave basin on breakwaters with armour layer of rocks and cubes, this paper examines the dependence of the reflection coefficient on wave directional spreading and obliquity. Results suggest that long-crested and short-crested waves give similar reflectio...

  1. Behaviour of a Kinetic Energy Projectile on Angular Impact

    Directory of Open Access Journals (Sweden)

    R. A. Goel

    1988-07-01

    Full Text Available Experiments of high velocity impact have been carried out with 30 mm armoured piercing projectiles on 55 mm thick hard steel plate. Angle of impact has been varied from 10" to 90". Damage inflicted on target with varying angle of impact has been reported and discussed in this paper. Comparative behaviour with 20 mm APP shot has also been discussed.

  2. Optimum Safety Levels for Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Sørensen, John Dalsgaard

    2005-01-01

    Optimum design safety levels for rock and cube armoured rubble mound breakwaters without superstructure are investigated by numerical simulations on the basis of minimization of the total costs over the service life of the structure, taking into account typical uncertainties related to wave stati...

  3. Model Testing and Reliability Evalution of the New Deepwater Breakwater at La Coruña, Spain

    DEFF Research Database (Denmark)

    Burcharth, Hans Falk; Maciñeira, Enrique; Canalejo, Pedro

    2003-01-01

    A new deepwater port development at Punta Langosteira near La Coruña is under design. Shelter is provided by a 2 km long rubble mound breakwater fully exposed to Atlantic waves. Max. water depth is 45 m, crownwall crest level is + 25 m and main armour blocks are 150 t cubes. Moorings for oil...

  4. Overtopping of Rubble Mound Breakwaters with Front Reservoir

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke

    2007-01-01

    The design and performance of breakwaters with front reservoir are discussed on the basis of physical 2-D model tests with a number of cross sections, in which vertopping discharge and spatial distribution, wave forces on inner parapet walls, and stability of reservoir armour were studied. The se...

  5. Stability of Hardly Reshaping Berm Breakwaters

    DEFF Research Database (Denmark)

    Andersen, Thomas Lykke; Van der Meer, Jentsje W.; Burcharth, Hans F.;

    2012-01-01

    The present paper deals with stability of berm breakwaters designed to be hardly or sometimes partly reshaping. Burcharth (2008, 2011) showed by comparison to the performance of a prototype berm breakwater that the Van der Meer formulae for stability of conventional rock armour including low cres...

  6. Depleted uranium weapons and international law: A precautionary approach

    NARCIS (Netherlands)

    A. McDonald; J.K. Kleffner; B. Toebes

    2008-01-01

    This books provides an in-depth analysis of the international legal aspects of the use of depleted uranium (DU) ammunition and armour. The military use of DU has been surrounded by considerable controversy, mainly as regards the health and environmental risks that such use entails. The debate about

  7. Impact of the Arundo scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) on the weight of Arundo donax (Poaceae: Arundinoideae) rhizomes in Languedoc southern France and Mediterranean Spain

    Science.gov (United States)

    Arundo donax L. (Poaceae) is native to Mediterranean Europe and invasive in the Rio Grande Basin of North America. Rhizomes from nine sites in France and Spain infested with a candidate control agent, the armoured scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) weighed 50% less than those fro...

  8. Quantum theory of shuttling instability in a movable quantum dot array

    DEFF Research Database (Denmark)

    Donarini, Andrea; Novotny, Tomas; Jauho, Antti-Pekka

    2004-01-01

    We study the shuttling instability in an array of three quantum dots the central one of which is movable. We extend the results by Armour and MacKinnon on this problem to a broader parameter regime. The results obtained by an efficient numerical method are interpreted directly using the Wigner...

  9. Model of rough bed for numerical simulation of saltation

    Czech Academy of Sciences Publication Activity Database

    Kharlamova, Irina; Vlasák, Pavel

    19, 3 (2015), s. 366-385. ISSN 1964-8189 R&D Projects: GA ČR GA103/09/1718; GA ČR GAP105/10/1574 Institutional support: RVO:67985874 Keywords : saltation * bed load transport * rough bed * armoured bed * bed roughness Subject RIV: BK - Fluid Dynamics Impact factor: 0.514, year: 2014

  10. Scaling of Core Material in Rubble Mound Breakwater Model Tests

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Z.; Troch, P.

    1999-01-01

    The permeability of the core material influences armour stability, wave run-up and wave overtopping. The main problem related to the scaling of core materials in models is that the hydraulic gradient and the pore velocity are varying in space and time. This makes it impossible to arrive at a full...

  11. Pre-Brazed Casting and Hot Radial Pressing: A Reliable Process for the Manufacturing of CFC and W Monoblock Mockups

    International Nuclear Information System (INIS)

    ENEA association is involved in the European International Thermonuclear Experimental Reactor (ITER) R-and-D activities and in particular for the manufacturing of high heat flux plasma-facing components (HHFC), such as the divertor targets, the baffles and the limiters: During the last years ENEA has manufactured actively cooled mock-ups by using different technologies, namely brazing, diffusion bonding and hot isostatic pressing (HIPping). A new manufacturing process has been set up and tested. It was successfully applied for the manufacturing of W armoured monoblock mockups. This technique is the HRP (Hot Radial Pressing) based on performing a radial diffusion bonding between the cooling tube and the armour tile by pressurizing only the internal tube and by keeping the joining zone in vacuum and at the required bonding temperature. The heating is obtained by a standard air furnace. The next step was to apply the HRP technique for the manufacturing of CFC armoured monoblock components. For this purpose some issues have to be solved like as the low CFC tensile strength, the pure copper interlayer between the heat sink and the armour necessary to mitigate the stress at the joint interface and the low wettability of the pure copper on the CFC matrix. This paper reports the research path followed to manufacture a medium scale vertical target CFC and W armoured mockup by HRP. An ad hoc rig able to maintain the CFC in a compressive constant condition was also designed and tested. The casting of a soft copper interlayer between the tube and the tile was performed by a new technique: the Pre-Brazed Casting (PBC, ENEA patent). Some mock-ups with three NB31 CFC tiles were successfully manufactured and tested to thermal fatigue using electron beam facilities. They all reached at least 1000 cycles at 20 MW/m2 without suffering any damage. The manufactured medium scale vertical target mock-up is now under testing at the FE2000 (France) facility. (author)

  12. Model test study on rock berms for protection of subsea pipelines against dragging anchors%海管碎石保护结构抵抗拖锚危害的模型试验研究

    Institute of Scientific and Technical Information of China (English)

    闫澍旺; 郭冠群; 任宇晓; 孙立强; 雷震名

    2015-01-01

    船舶走锚时可能对海底管线造成破坏,实际工程中常用碎石保护结构来对海底管道进行保护。为了研究这种结构的保护效果和保护机理,在大型试验槽中对三种尺寸模型锚进行了模型试验。在试验中测量了锚爪尖端位置和锚爪力在保护结构中的变化,得到锚体从细砂进入保护结构时的运动过程和运动规律,据此研究了碎石保护结构对海底管线的保护效果并分析了保护机理。%The submarine pipeline may be damaged by the dragging anchors of ships. The rock armour berms are commonly used for pipeline protection in practical engineering. Little research work has been found in the existing literature for the armour berms. To study the protection mechanism and efficiency of this kind of armour berms, model tests were carried out in a model tank, in which foundation soil and the armour berm were simulated. Three model anchors with different sizes were adopted in the tests. By observing the trajectories of the dragging anchors in foundation soil and in the armour berm, it is possible to obtain the movement process and rule of anchor in sand and rock berms. The protection mechanism of rock berms for submarine pipelines against dragging anchors is discussed.

  13. Use of Quantitative Morphological Analysis Combined with a Large Sample Size for Estimating Morphological Variability in a Case Study of Armoured Mite Carabodes subarcticus Trägårdh, 1902 (Acari: Oribatida: Carabodidae / Carabodes Subarcticus Trägårdh, 1902 (Acari: Oribatida: Carabodidae Bruòçrèu Taksonomijâ Plaðâk Pielietoto Pazîmju Morfoloìijas Mainîbas Kvantitatîva Un Kvalitatîva Analîze Relatîvi Lielâ Paraugkopâ

    Directory of Open Access Journals (Sweden)

    Kagainis Uìis

    2015-12-01

    Full Text Available The morphology of Oribatida and similar little-known groups of organisms varies considerably, which complicates morphological analysis (e.g. species descriptions. Qualitative analyses have been carried out mostly on a small number of individuals (n < 25. There is lack of studies dealing with mechanisms of how that variation can change in relation to sample size and insufficient discussion on whether qualitative or quantitative analysis is more appropriate for description of morphological variability. A total of 500 adult Carabodes subarcticus Trägårdh, 1902 Oribatida were collected from a local population. Six qualitative and six quantitative traits were characterised using light microscopy and scanning electron microscopy. The relationships between the sample size of different subsamples (n < 500 and morphological variation were examined using randomised selection (10 000 replicates and calculation of the percentage of cases in which the sizevalues were within a certain distance (less than 10%, 25%, or 50% from the range of the reference population (n = 500. Qualitative traits were significantly less variable than quantitative due to binomial distribution of the obtained data; thus they were less comparable and interpretive to describe morphological variability. When sample size was small (n < 25, in less than 2 to 15% of cases the observed variability was within 10% distance of the range of the reference population. Larger sample sizes resulted in size-ranges that approached those of the reference population. It is possible that execution of quantitative characterisation and use of relatively larger sample sizes could improve species descriptions by characterising the morphological variability more precisely and objectively.

  14. Studies on Some Aspects of Propellants for Improving the Performance of Tank Guns

    Directory of Open Access Journals (Sweden)

    K. P. Rao

    1987-01-01

    Full Text Available The main criterion, in the design of propellant charge for a tank gun, is to achieve the highest possible muzzle velocity for fin stabilized armour piercing dicarding sabot (FSAPDS projectiles. This ensures penetration through the toughest armour plates by the kinetic energy of the projectile. One of the solutions, is to increase the force constant of the propellant. Higher force constant from conventional double and triple base propellant compositions lead to prohibitive linear rates of burning coefficients. ERDL has developed a high energy propellant based on RDX, with very high force constant and low linear rate of burning coefficient. The objective of the present paper is to discuss various aspects of the interior ballistics of the three types of propellants in question in 105 mm tank gun with FSAPDS ammunition. The study shows that only the solution with RDX base propellant is feasible for an increase of three per cent in muzzle velocity.

  15. Mechanisms of erosion in miocene clays from the Tudela formation (Bardenas Reales, Navarra, Spain)

    International Nuclear Information System (INIS)

    In Bardenas Reales area (located in the central-western part of the Ebro Depression) several erosion rates have been measured along the last years. The mean annual erosion rates are of 32 Tm/Ha/yr. Due to semiarid conditions, precipitation is irregularly distributed along the year with maximums on spring and autumn when the great erosion is produced. There are intensity and quality thresholds below which erosion does not take place. In Bardenas Reales some erosion processes act (mud slides and armoured mud balls among others). Mud slides are mobilised on spring when the sediment have reached its plastic limit and could slide due to heavy rains. Armored mud balls are produced by the enhancement of popcorn cracks that individualize clays cores which are rounded by water. The same kind of strong precipitation that mobilised mud slides is the responsible of armoured mud balls destruction because the conditions to its maintenance are very limited. (Author) 9 refs.

  16. Active Protection System for AFV application – Current trends and future requirement – A study report

    Directory of Open Access Journals (Sweden)

    Vivek.R

    2012-07-01

    Full Text Available A combat vehicle is a self-propelled weaponplatform. Light Weight and high performance arethe key factors for the design of a combat vehicle.Most of the weight is distributed to structuralarmour purposes. Rolled Homogenous Armour(RHA steel and composite armour played adominant role to counter these threats. But thethreat to the combat vehicles has increasedmanifold due to advancement in weapontechnologies and there is a necessity of protectingthe vehicles from these threats. The protections bymeans of RHA steel will lead to increase in weight,which affects the mobility of the vehicle. Hencethere is a need to adopt active protectiontechnologies to effectively counter the incominganti-tank threats/ ammunitions before hitting thevehicle thereby enhancing its survivability. Thispaper highlights the current trends and futurerequirement in the field of Active Protectiontechnologies.

  17. Affordable thermal imaging systems for the UK light-armored vehicle fleet

    Science.gov (United States)

    Cameron, Ian

    2003-01-01

    This paper describes the background to the planned upgrade of the UK Light Armoured Vehicle fleet, focussing specifically on the introduction of Thermal Imaging and Tactical Navigation systems which meet the requirement to conduct 24 hour operations and enhance the situational awareness of the crew. The main bulk of the paper will concentrate on the Battle Group Thermal Imaging (BGTI) system(s) selected by the UK Ministry of Defence (MoD) to be installed on the Warrior Armoured Infantry Fighting Vehicle (AIFV) and Scimitar Close Recce vehicle. In particular the paper will describe the Gunners Sight, the integrated Commanders Crew Station, the Tactical Navigation sub-system and the interfacing of the Thales Optronics BGTI system to the General Dynamics Bowman Radio and Battlefield Management System (BMS). Throughout the paper, the Author will make reference to the need to offer affordable solutions that ensure the total cost to the UK MoD is kept within their budget.

  18. Mechanisms of erosion in miocene clays from the Tudela formation (Bardenas Reales, Navarra, Spain); Mecanismos de erosion en arcillas miocenas de la Formacion Tudela (Bardenas Reales, Navarra, Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Marin, C.; Desir, G.

    2009-07-01

    In Bardenas Reales area (located in the central-western part of the Ebro Depression) several erosion rates have been measured along the last years. The mean annual erosion rates are of 32 Tm/Ha/yr. Due to semiarid conditions, precipitation is irregularly distributed along the year with maximums on spring and autumn when the great erosion is produced. There are intensity and quality thresholds below which erosion does not take place. In Bardenas Reales some erosion processes act (mud slides and armoured mud balls among others). Mud slides are mobilised on spring when the sediment have reached its plastic limit and could slide due to heavy rains. Armored mud balls are produced by the enhancement of popcorn cracks that individualize clays cores which are rounded by water. The same kind of strong precipitation that mobilised mud slides is the responsible of armoured mud balls destruction because the conditions to its maintenance are very limited. (Author) 9 refs.

  19. Wave Induced Loading and Stability of Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Hald, Tue

    conducting model tests very large variability in e.g. the degree of stability is observed. This background motivated the investigations conducted in the present study. The objective was to investigate and clarify which wave parameters are important for the hydraulic stability of the armour layer on typical...... rubble mound breakwaters. Furthermore, it was intended to quantify the influence on the stability of each parameter. Focus was put on the wave induced loading on single armour stones and the relation to the stability. Based on existing literature the state of physical understanding of the processes...... related to the hydraulic stability was discussed. Further, governing parameters influencing the stability were identified and their influence quantified to retrieve the state- of-the-art. Model tests were conducted at SINTEF with scale models of prototype breakwaters and both the wave induced loading and...

  20. On Front Slope Stability of Berm Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    reshaping of a large Norwegian breakwater exposed to the North Sea waves. As a motivation for applying the Van der Meer formula a discussion of design parameters related to berm breakwater stability formulae is given. Comparisons of front erosion predicted by the use of the Van der Meer formula with model......The short communication presents application of the conventional Van der Meer stability formula for low-crested breakwaters for the prediction of front slope erosion of statically stable berm breakwaters with relatively high berms. The method is verified (Burcharth, 2008) by comparison with the......, relative berm width, method of armour stone placement, and hydraulic parameters. The formulae should cover the structure range from statically stable berm breakwaters to conventional double layer armoured breakwaters....

  1. Overview and status of ITER internal components

    International Nuclear Information System (INIS)

    Highlights: • Manufacturing technologies for the ITER internal components have been developed. • The Blanket System successfully went through its Final Design Review in April 2013. • The decision to start operation with a Divertor with a full-W armour has been taken. - Abstract: The internal components of ITER are one of the most design and technically challenging components of the ITER machine, and include the Blanket System and the Divertor. The Blanket System successfully went through its Final Design Review in April 2013 and now it is entering into the procurement phase. The design and qualification of the Divertor with a full-tungsten armour was successfully completed and this enabled the decision in November 2013 to start operation with this material option. This paper summarizes the engineering design, the R and D, the technology qualification and procurement status of the Blanket System and of the Divertor of the ITER machine

  2. Overview and status of ITER internal components

    Energy Technology Data Exchange (ETDEWEB)

    Merola, Mario, E-mail: mario.merola@iter.org; Escourbiac, Frederic; Raffray, René; Chappuis, Philippe; Hirai, Takeshi; Martin, Alex

    2014-10-15

    Highlights: • Manufacturing technologies for the ITER internal components have been developed. • The Blanket System successfully went through its Final Design Review in April 2013. • The decision to start operation with a Divertor with a full-W armour has been taken. - Abstract: The internal components of ITER are one of the most design and technically challenging components of the ITER machine, and include the Blanket System and the Divertor. The Blanket System successfully went through its Final Design Review in April 2013 and now it is entering into the procurement phase. The design and qualification of the Divertor with a full-tungsten armour was successfully completed and this enabled the decision in November 2013 to start operation with this material option. This paper summarizes the engineering design, the R and D, the technology qualification and procurement status of the Blanket System and of the Divertor of the ITER machine.

  3. Investigation of radiation keeping property of barite coated cloth via image processing method

    International Nuclear Information System (INIS)

    Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

  4. THE RAILWAYS AND THE WAR EFFORT, 1939-1945

    Directory of Open Access Journals (Sweden)

    R.J. Bouch

    2012-02-01

    Full Text Available South Africa's armed forces were small, and their material resources meagre, when the country entered the Second World War on 6 September 1939. The Permanent Force was nearly 50% under strength; the shortage of trained infantrymen was estimated at over 39000; ammunition for artillery pieces and anti-aircraft guns was sufficient for one day's shooting, and only two obsolete armoured cars were available. Two experimental armoured cars had been built locally. During the first years of the war it was not possible to obtain much equipment from the United Kingdom or the United States. Local ingenuity was heavily taxed as attention concentrated on preparing the South African armed forces for long campaigns. Gradually regiments were mobilized and equipped, and an extensive munitions production drive was launched

  5. Wave interaction with large roughness elements on an impermeable sloping bed

    DEFF Research Database (Denmark)

    Jensen, Bjarne; Christensen, Erik Damgaard; Sumer, B. Mutlu

    2012-01-01

    The present paper presents the results of an experimental and numerical investigation of the flow between large roughness elements on a steep sloping impermeable bed during wave action. The setup is designed to resemble a breakwater structure. The work is part of a study where the focus is on the...... details in the porous core flow and the armour layer flow i.e. the interaction between the two flow domains and the effect on the armour layer stability. In order to isolate the processes involved with the flow in the porous core the investigations are first carried out with a completely impermeable bed...... hereby add more details to the understanding of the fluid-structure interaction....

  6. Ballistic studies on layered structures

    International Nuclear Information System (INIS)

    This paper presents the ballistic behavior and penetration mechanism of metal-metal and metal-fabric layered structures against 7.62 armour piercing projectiles at a velocity of 840 ± 15 m/s at 30o angle of impact and compares the ballistic results with that of homogeneous metallic steel armour. This study also describes the effect of keeping a gap between the target layers. Experimental results showed that among the investigated materials, the best ballistic performance was attained with metal-fabric layered structures. The improvements in ballistic performance were analyzed in terms of mode of failure and fracture mechanisms of the samples by using optical and electron microscope, X-ray radiography and hardness measurement equipments.

  7. Investigation of radiation keeping property of barite coated cloth via image processing method

    Energy Technology Data Exchange (ETDEWEB)

    Kilincarslan, S.; Akkurt, I.; Molla, T.; Akarslan, F. [Department of Construction Education, Suleyman Demirel University, Isparta (Turkey); Department of Physics, Science Faculty, Suleyman Demirel University, Isparta (Turkey); Department of Construction Education, Suleyman Demirel University, Isparta (Turkey); Textil Engineering, Engineering Faculty, Suleyman Demirel University, Isparta (Turkey)

    2012-09-06

    Preservative clothes which are able to absorb radiation beam are needed not only for saving people working at radioactive environment but also for saving others from natural and man-made radiation sources we are exposed in daily life. Barite is a mineral which can be used for armour plating because of high atomic numbered element barium constituent of barite. In this study, armour plating property of barite was applied to fabrics. Barite coated fabric having characteristic of keeping radiation was obtained by penetrating barite on cloth via coating method. Radiation keeping property of fabrics obtained was determined via image processing. The results of experiments showed that barite coated fabrics have blocked radiation more than normal fabrics have done.

  8. 2-D Model Test of Dolosse Breakwater

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Liu, Zhou

    1994-01-01

    The rational design diagram for Dolos armour should incorporate both the hydraulic stability and the structural integrity. The previous tests performed by Aalborg University (AU) made available such design diagram for the trunk of Dolos breakwater without superstructures (Burcharth et al. 1992). To...... extend the design diagram to cover Dolos breakwaters with superstructure, 2-D model tests of Dolos breakwater with wave wall is included in the project Rubble Mound Breakwater Failure Modes sponsored by the Directorate General XII of the Commission of the European Communities under Contract MAS-CT92......-0042. Furthermore, Task IA will give the design diagram for Tetrapod breakwaters without a superstructure. The more complete research results on Dolosse can certainly give some insight into the behaviour of Tetrapods armour layer of the breakwaters with superstructure. The main part of the experiment was on the...

  9. The Effect of the Propeller Jet on Pile Groups

    Institute of Scientific and Technical Information of China (English)

    Kubilay Cihan

    2014-01-01

    The objective of this study is to determine the effect of jet propeller on the damage of berthing structures combined of armoured slope with pile groups. For this purpose, scour measurements were performed for four types berthing structures, which were armoured slope with tandem arrangements of piles for two and three piles and with side by side arrangements of piles for two and three piles. The effect of gap between piles on damage was investigated. The damage level induced by propeller jet between piles was determined. The gaps were 1, 2, 3, and 4 times the pile diameter. Three different values of Rpm (690, 820, and 950) were chosen for the tests. The diameter of circular piles is 40 mm. The slope ratio was 1/3 and the diameter of propeller was 10 cm.

  10. Controlled assembly of jammed colloidal shells on fluid droplets.

    Science.gov (United States)

    Subramaniam, Anand Bala; Abkarian, Manouk; Stone, Howard A

    2005-07-01

    Assembly of colloidal particles on fluid interfaces is a promising technique for synthesizing two-dimensional microcrystalline materials useful in fields as diverse as biomedicine, materials science, mineral flotation and food processing. Current approaches rely on bulk emulsification methods, require further chemical and thermal treatments, and are restrictive with respect to the materials used. The development of methods that exploit the great potential of interfacial assembly for producing tailored materials have been hampered by the lack of understanding of the assembly process. Here we report a microfluidic method that allows direct visualization and understanding of the dynamics of colloidal crystal growth on curved interfaces. The crystals are periodically ejected to form stable jammed shells, which we refer to as colloidal armour. We propose that the energetic barriers to interfacial crystal growth and organization can be overcome by targeted delivery of colloidal particles through hydrodynamic flows. Our method allows an unprecedented degree of control over armour composition, size and stability. PMID:15937488

  11. Condition-orientated maintenance with the aid of visualisation of wear data and change predictions; Zustandsorientierte Instandhaltung anhand Visualisierung von Verschleissdaten und Wechselprognosen

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Volker [RAG Deutsche Steinkohle AG, Marl (Germany). Bergwerk Auguste Victoria; Piejede, Peter [RAG Deutsche Steinkohle AG, Herne (Germany). Servicebereich Technik und Logistik

    2011-01-15

    Because of the greater concentration of underground workings in the German coal mining industry in a few high-output faces condition-orientated maintenance of conveying equipment is becoming increasingly important. The most diverse methods are used. For example, the abrasive parameters are of special importance for the armoured face conveyors with their high mechanical loads. The contribution explains the individual wear situations are as well as their evaluations on practical examples. (orig.)

  12. Modelling of massive particulates for breakwater engineering using coupled FEMDEM and CFD

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The seaward slope of many breakwaters consists of thousands of interlocking units of rock or concrete comprising a massive granular system of large elements each weighing tens of tonnes.The dumped quarry materials in the core are protected by progressively coarser particulates.The outer armour layer of freely placed units is intended to both dissipate wave energy and remain structurally stable as strong flows are drawn in and out of the particulate core.Design guidance on the mass and shape of these units is based on empirical equations derived from sealed physical model tests.The main failure mode for armour layers exposed to severe storms is hydraulic instability where the armour units of concrete or rock are subjected to uplift and drag forces which can in turn lead to rocking,displacement and collisions sufficient to cause breakage of units.Recently invented armour unit designs making up such granular layered system owe much of their success to the desirable emergent properties of interlock and porosity and how these combine with individual unit structural strength and inertial mass. Fundamental understanding of the forces governing such wave-structure interaction remains poor.We use discrete element and combined finite-discrete element methods to model the granular solid skeleton of randomly packed units coupled to a CFD code which resolves the wave dynamics through an interface tracking technique.The CFD code exploits several methods including a compressive advection scheme, node movement, and general mesh optimization.We provide the engineering context and report progress towards the numerical modelling of instability in these massive granular systems.

  13. Dependence of saltation characteristics on bed organisation in numerical simulation

    Czech Academy of Sciences Publication Activity Database

    Kharlamova, Irina; Vlasák, Pavel

    19, 1 (2015), s. 177-184. ISSN 1226-4806 R&D Projects: GA ČR GA103/09/1718; GA ČR GAP105/10/1574 Institutional support: RVO:67985874 Keywords : saltation parameters * bed roughness * bed structure * bed load transport * armoured bed Subject RIV: BK - Fluid Dynamics Impact factor: 0.519, year: 2013 http://link.springer.com/content/pdf/10.1007%2Fs12303-014-0029-3.pdf

  14. Delamination toughness of ultra high molecular weight polyethylene (UHMWPE) composites

    OpenAIRE

    Casas-Rodriguez J.P.; Tellez J.; Porras A.

    2012-01-01

    Ultra high molecular weight polyethylene (UHMWPE) fibre reinforced composites are an important group of material for armours solutions, where their unique combination of properties could be utilized. A commonly observed failure mode in this kind of unidirectional laminated composites under impact ballistic is delamination between the composite layers. In the present study, an investigation on the delamination toughness behaviour exhibited by UHMWPE composites laminated was made. The interlami...

  15. Team 7: Applying Automated Red Teaming in an Urban Ops Scenario

    OpenAIRE

    Lee, M.; Ang, D; Huee, L. Fung

    2006-01-01

    With rapid urbanisation, troops today will have to operate in an increasingly complex and urbanised environment. Together with a more potent enemy capability, the troops will have to be highly armour protected even at the lowest level (company size) in order to minimise the casualty rate. The fighting force will need to be a combined force to achieve a swift and decisive result in an urbanised terrain. This study explored the Coy level urban fighting force pack...

  16. Alloys and composites of polybenzoxazines properties and applications

    CERN Document Server

    Rimdusit, Sarawut; Tiptipakorn, Sunan

    2013-01-01

    This book provides an introduction to the unique and fascinating properties of alloys and composites from novel commercialized thermosetting resins based on polybenzoxazines. Their outstanding properties such as processability, thermal, mechanical, electrical properties as well as ballistic impact properties of polybenzoxazine alloys and composites make them attractive for various applications in electronic packaging encapsulation, light weight ballistic armour composites and bipolar plate in fuel cells.

  17. Nexans Tracking System. An indoor positioning system using Bluetooth Low Energy

    OpenAIRE

    Holm, Ragnhild Kosmo

    2015-01-01

    Nexans Rognan is a cable manufacturer located in Nordland County. Each new cable order have a set of requirements provided by the customer. The cable specifications change in terms of characteristics of fibre optical elements, type and quality of cable armouring and dimension and amounts of electrical conductors. Due to the variety in different cables produced, they also need a wide array of different cable drums available at the plant. The drums are stored in sporadic locat...

  18. Global- and local-scale characterisation of bed surface structure in coarse-grained alluvial rivers

    Science.gov (United States)

    Powell, Mark; Ockelford, Annie; Nguyen, Thao; Wood, Jo; Rice, Steve; Reid, Ian; Tate, Nick

    2013-04-01

    It is widely recognised that adjustments in bed surface grain size (texture) and grain arrangement (structure) exert significant controls on the stability of coarse-grained alluvial rivers. Modifications to bed surface texture and structure occur during active sediment transport and are mediated by the process of mobile armouring which concentrates coarser-than-average particles on the surface and organises them into a variety of grain- and bedform-scale configurations. Textural aspects of surface armouring are well understood to the extent that sediment transport models can be used to predict the size distribution of armours that develop under different sediment supply regimes and shear stresses. Research has also found that the adjustment of bed surface grain size is often patchy and that the development of finer-grained and coarser-grained areas of the bed has important implications for both the rate and grain size of transported sediment. The structural aspects of stream-bed armouring, however, are less well understood, largely because of the difficulty of recognising and characterising bedforms and bed-structures that have dimensions similar to their constituent particles. Moreover, bed structure is generally parameterised using global scale descriptors of the bed surface such that information on the spatial heterogeneity of the structure is lost. The aim of this poster is to characterise the structural characteristics of water-worked river gravels, paying particular attention to quantifying the spatial heterogeneity of those characteristics using local scale descriptors. Results reported from a number of flume experiments designed to simulate the spatio-temporal evolution of bed configurations (surface texture and structure) as the system adjusts to a condition of equilibrium transport are used to evaluate the spatial variability of bed surface structure and explore its significance for modelling sediment transport rates in gravel-bed rivers. Keywords: bed

  19. Assessment and control of shielding in medical radiology

    International Nuclear Information System (INIS)

    The establishment of adequate shielding is a guarantor of the application of the ALARA principle. This work provides a method for the assessment of the thickness of shields and armouring of a medical radiology control room. An application of this method was performed for the verification of the thicknesses of protective barriers at AMIT (Association Médicale Inter-entreprises de Tananarive) center Behoririka, Antananarivo, Madagascar.

  20. Finite Element Analysis Of Large Deformation Of Articular Cartilage In Upper Ankle Joint Of Occupant In Military Vehicles During Explosion

    OpenAIRE

    Klekiel T.; Będziński R.

    2015-01-01

    The paper presents the analysis of the load of lower limbs of occupants in the armoured military vehicle, which has been destroyed by detonation of the Improvised Explosive Device (IED) charge under the vehicle. A simplified model of the human lower limb focused on upper ankle joint was developed in order to determine the reaction forces in joints and load in particular segments during the blast load. The model of upper ankle joint, include a tibia and an ankle bone with corresponding articul...

  1. Case Hardening of Hardox 450 Steel for Increased Ballistic Strength

    OpenAIRE

    Buberg, Tor Arne

    2011-01-01

    AbstractSteel alloys are the material that is most used in protective constructions today. The reason is the overall good properties of steels, with its high strength and hardness, high ductility, high formability and relatively low cost compared to other materials. Even though armour steels are affordable, work is done to limit expenses from production or come up with new and less expensive alloys.Case hardening is a technique for production of steel with a very hard and durable surface whil...

  2. Note on Modern Trends in Heavy Vehicle Electrical Electronic systems

    Directory of Open Access Journals (Sweden)

    B. S. Sastry

    1982-04-01

    Full Text Available The paper presents an overview of some of the aerospace control systems that are being successfully adopted in the field of Armoured Fighting Vehicles. An automatic electronic transmission controller for an epicyclic gear box with a torque converter to select the forward and reverse speeds in a sequential logic has been developed. Transducers developed for monitoring various engine and transmission parameters are being used for Electronic Fuel Injection (EFI, variable valve timings and electronic governing.

  3. Microcontroller based ground weapon control system(Short Communication)

    OpenAIRE

    M. Sankar Kishore

    2001-01-01

    Armoured vehicles and tanks generally consist of high resolution optical (both infrared and visible) and display systems for recognition and identification of the targets. Different weapons/articles to engage the targets may be present. A fire control system (FCS) controls all the above systems, monitors the status of the articles present and passes the information to the display system. Depending upon the health and availability of the articles, the FCS selects and fires the articles....

  4. Energy deposition and thermal effects of runaway electrons in ITER-FEAT plasma facing components

    International Nuclear Information System (INIS)

    The profile of energy deposited by runaway electrons (RAEs) of 10 or 50 MeV in International Thermonuclear Experimental Reactor-Fusion Energy Advanced Tokamak (ITER-FEAT) plasma facing components (PFCs) and the subsequent temperature pattern have been calculated by using the Monte Carlo code FLUKA and the finite element heat conduction code ANSYS. The RAE energy deposition density was assumed to be 50 MJ/m2 and both 10 and 100 ms deposition times were considered. Five different configurations of PFCs were investigated: primary first wall armoured with Be, with and without protecting CFC poloidal limiters, both port limiter first wall options (Be flat tile and CFC monoblock), divertor baffle first wall, armoured with W. The analysis has outlined that for all the configurations but one (port limiter with Be flat tile) the heat sink and the cooling tube beneath the armour are well protected for both RAE energies and for both energy deposition times. On the other hand large melting (W, Be) or sublimation (C) of the surface layer occurs, eventually affecting the PFCs lifetime

  5. ITER transient consequences for material damage: modelling versus experiments

    International Nuclear Information System (INIS)

    Carbon-fibre composite (CFC) and tungsten macrobrush armours are foreseen as PFC for the ITER divertor. In ITER the main mechanisms of metallic armour damage remain surface melting and melt motion erosion. In the case of CFC armour, due to rather different heat conductivities of CFC fibres a noticeable erosion of the PAN bundles may occur at rather small heat loads. Experiments carried out in the plasma gun facilities QSPA-T for the ITER like edge localized mode (ELM) heat load also demonstrated significant erosion of the frontal and lateral brush edges. Numerical simulations of the CFC and tungsten (W) macrobrush target damage accounting for the heat loads at the face and lateral brush edges were carried out for QSPA-T conditions using the three-dimensional (3D) code PHEMOBRID. The modelling results of CFC damage are in a good qualitative and quantitative agreement with the experiments. Estimation of the droplet splashing caused by the Kelvin-Helmholtz (KH) instability was performed

  6. Simulating three dimensional wave run-up over breakwaters covered by antifer units

    Directory of Open Access Journals (Sweden)

    Najafi-Jilani A.

    2014-06-01

    Full Text Available The paper presents the numerical analysis of wave run-up over rubble-mound breakwaters covered by antifer units using a technique integrating Computer-Aided Design (CAD and Computational Fluid Dynamics (CFD software. Direct application of Navier-Stokes equations within armour blocks, is used to provide a more reliable approach to simulate wave run-up over breakwaters. A well-tested Reynolds-averaged Navier-Stokes (RANS Volume of Fluid (VOF code (Flow-3D was adopted for CFD computations. The computed results were compared with experimental data to check the validity of the model. Numerical results showed that the direct three dimensional (3D simulation method can deliver accurate results for wave run-up over rubble mound breakwaters. The results showed that the placement pattern of antifer units had a great impact on values of wave run-up so that by changing the placement pattern from regular to double pyramid can reduce the wave run-up by approximately 30%. Analysis was done to investigate the influences of surface roughness, energy dissipation in the pores of the armour layer and reduced wave run-up due to inflow into the armour and stone layer.

  7. Feature extraction for ultrasonic sensor based defect detection in ceramic components

    Science.gov (United States)

    Kesharaju, Manasa; Nagarajah, Romesh

    2014-02-01

    High density silicon carbide materials are commonly used as the ceramic element of hard armour inserts used in traditional body armour systems to reduce their weight, while providing improved hardness, strength and elastic response to stress. Currently, armour ceramic tiles are inspected visually offline using an X-ray technique that is time consuming and very expensive. In addition, from X-rays multiple defects are also misinterpreted as single defects. Therefore, to address these problems the ultrasonic non-destructive approach is being investigated. Ultrasound based inspection would be far more cost effective and reliable as the methodology is applicable for on-line quality control including implementation of accept/reject criteria. This paper describes a recently developed methodology to detect, locate and classify various manufacturing defects in ceramic tiles using sub band coding of ultrasonic test signals. The wavelet transform is applied to the ultrasonic signal and wavelet coefficients in the different frequency bands are extracted and used as input features to an artificial neural network (ANN) for purposes of signal classification. Two different classifiers, using artificial neural networks (supervised) and clustering (un-supervised) are supplied with features selected using Principal Component Analysis(PCA) and their classification performance compared. This investigation establishes experimentally that Principal Component Analysis(PCA) can be effectively used as a feature selection method that provides superior results for classifying various defects in the context of ultrasonic inspection in comparison with the X-ray technique.

  8. Effect of joint design on ballistic performance of quenched and tempered steel welded joints

    International Nuclear Information System (INIS)

    Highlights: • Traditional usage of austenitic stainless steel filler for armour steel welding shows poor ballistic performance. • Earlier efforts show dubious success on ballistic resistance of armour steel joints. • Comparative evaluation of equal/unequal joint design on ballistic performance. • Effect of joint design covers the main aspects of successful bullet stoppage. - Abstract: A study was carried out to evaluate the effect of joint design on ballistic performance of armour grade quenched and tempered steel welded joints. Equal double Vee and unequal double Vee joint configuration were considered in this study. Targets were fabricated using 4 mm thick tungsten carbide hardfaced middle layer; above and below which austenitic stainless steel layers were deposited on both sides of the hardfaced interlayer in both joint configurations. Shielded metal arc welding process was used to deposit for all layers. The fabricated targets were evaluated for its ballistic performance and the results were compared in terms of depth of penetration on weld metal. From the ballistic test results, it was observed that both the targets successfully stopped the bullet penetration at weld center line. Of the two targets, the target made with unequal double Vee joint configuration offered maximum resistance to the bullet penetration at weld metal location without any bulge at the rear side. The higher volume of austenitic stainless steel front layer and the presence of hardfaced interlayer after some depth of soft austenitic stainless steel front layer is the primary reason for the superior ballistic performance of this joint

  9. Technologies for the ITER divertor vertical target plasma facing components

    International Nuclear Information System (INIS)

    The ITER divertor vertical target (VT) has to sustain heat fluxes up to 20 MW/m2. The concept developed for this Plasma Facing Component (PFC) working at steady state is based on Carbon Fibre Composite (CFC) armour for the lower straight part and tungsten (W) for the curved upper part. The main challenges of such components are to be able to remove the high deposited heat fluxes and to join mechanically and thermally armour to the metallic heat sink, despite of the mismatch of the thermal expansions. Two solutions based on the use of CuCrZr hardened copper alloy and active metal casting (AMC) process were investigated during the ITER EDA phase: the first one called 'flat tile geometry' was mainly developed for Tore Supra pumped limiter, the second one called 'monoblock geometry' was developed by the EU Participating Team for the ITER project. This paper presents a review of these two solutions and analyses their assets and drawbacks: pressure drop, critical heat flux, surface temperature and expected behaviour during operation, risks during the manufacture, controls of the armour defects during the manufacture and at the reception and possibility to repair defected tiles. (author)

  10. Cube or block. Statistical analysis, historial review, failure mode and behaviour; Cubo o bloque. Ajuste estadistico, analisis historico, modo de fallo y comportamiento

    Energy Technology Data Exchange (ETDEWEB)

    Negro, V.; Varela, O.; Campo, J. M. del; Lopez Gutierrez, J. S.

    2010-07-01

    Many different concrete shapes have been developed as armour units for rubble mound breakwaters. Nearly all are mass concrete construction and can be classified as random placed or regular patterns Placed. the majority of artificial armour unit are placed in two layers and they are massive. they intended to function in a similar way to natural rock (cubes, blocks, antifer cubes,...). More complex armour units were designed to achieve greater stability by obtaining a high degree of interlock (dolosse, accropode, Xbloc, core-loc,...). finally, the third group are the regular pattern placed units with a greater percentage of voids for giving a stronger dissipation of cement hydration (cob, shed, hollow cubes,...), This research deals about the comparison between two massive concrete units, the cubes and the blocks and the analysis of the geometry, the porosity, the construction process and the failure mode. The first stage is the statistical analysis. the scope of it is based on the historical reference of the Spanish Breakwaters with main layer of cubes and blocks (ministry of Public Works, General Directorate of Ports, 1988). (Author) 9 refs.

  11. IRAQ 2003 (PART 2: THE ROAD TO BAGHDAD

    Directory of Open Access Journals (Sweden)

    Leopold Scholtz

    2012-02-01

    Full Text Available The operational plansThe attack on Iraq, or Operation Iraqi Freedom as it was called, would be very different from its predecessor Operation Desert Storm, 12 years before. The main strategic difference was, of course, the fact that Desert Storm encompassed an enormous international military coalition, with ground, air and naval forces being supplied by America, Britain, France, Italy, Australia, Argentina, Saudi Arabia, Egypt and Syria. Iraqi Freedom was shouldered by only two countries, the US and the UK, with Australia supplying a small contingent of SAS troops, the Czech Republic a platoon of chemical warfare troops and Spain a hospital ship.To drive the Iraqi occupying forces out of Kuwait in 1991, an enormous force of 15 divisions had been amassed. These had been organised into 3 American corps (XVIII Airborne Corps, consisting of two airborne divisions, a mechanised infantry division, as well as a French light armoured division; VII Corps, consisting of three US and one UK armoured divisions and one US mechanised infantry division; and a US Marine corps, consisting of two Marine divisions, a Saudi Arabian corps of two divisions, an Egyptian corps of two divisions, and a Syrian division.3 For Iraqi Freedom, only a single army corps (V, consisting of two mechanised infantry divisions and an airborne division, together with a marine division, an understrength composite British armoured division, and some smaller independent units, was available. And because of political wrangling, one mechanised infantry division arrived far too late on the battlefield to participate in the fighting. So, compared to 15 divisions in 1991, the job would now have to be done by only four. Nevertheless, with the new American weapons of precision and the extremely able Abrams tank, a repeat of Gulf War I was not really necessary.

  12. Ecological implications of extreme events: footprints of the 2010 earthquake along the Chilean coast.

    Science.gov (United States)

    Jaramillo, Eduardo; Dugan, Jenifer E; Hubbard, David M; Melnick, Daniel; Manzano, Mario; Duarte, Cristian; Campos, Cesar; Sanchez, Roland

    2012-01-01

    Deciphering ecological effects of major catastrophic events such as earthquakes, tsunamis, volcanic eruptions, storms and fires, requires rapid interdisciplinary efforts often hampered by a lack of pre-event data. Using results of intertidal surveys conducted shortly before and immediately after Chile's 2010 M(w) 8.8 earthquake along the entire rupture zone (ca. 34-38°S), we provide the first quantification of earthquake and tsunami effects on sandy beach ecosystems. Our study incorporated anthropogenic coastal development as a key design factor. Ecological responses of beach ecosystems were strongly affected by the magnitude of land-level change. Subsidence along the northern rupture segment combined with tsunami-associated disturbance and drowned beaches. In contrast, along the co-seismically uplifted southern rupture, beaches widened and flattened increasing habitat availability. Post-event changes in abundance and distribution of mobile intertidal invertebrates were not uniform, varying with land-level change, tsunami height and coastal development. On beaches where subsidence occurred, intertidal zones and their associated species disappeared. On some beaches, uplift of rocky sub-tidal substrate eliminated low intertidal sand beach habitat for ecologically important species. On others, unexpected interactions of uplift with man-made coastal armouring included restoration of upper and mid-intertidal habitat seaward of armouring followed by rapid colonization of mobile crustaceans typical of these zones formerly excluded by constraints imposed by the armouring structures. Responses of coastal ecosystems to major earthquakes appear to vary strongly with land-level change, the mobility of the biota and shore type. Our results show that interactions of extreme events with human-altered shorelines can produce surprising ecological outcomes, and suggest these complex responses to landscape alteration can leave lasting footprints in coastal ecosystems. PMID:22567101

  13. Study on seismic stability of seawall in man-made island. Pt. 5. Deformation of actual seawall during earthquake and estimation of seismic performance

    International Nuclear Information System (INIS)

    In the development of the man-made island siting technology of nuclear power plants, assessing the stability of the seawall against large ocean waves and earthquakes is indispensable. Concerning the seismic stability of the seawall, prediction of the deformation of the seawall during earthquake is important to evaluate the seismic performance of the seawall after the earthquake. In the this report, the deformation of the actual seawall was predicted from the results of the centrifuge model tests and the case studies by the numerical analyses. Furthermore, wave flume model tests of the seawall with the deformed armour embankment by the earthquake shaking were conducted to investigate the effects of the deformation of the armoured embankment to the overtopping discharge by the waves. Obtained results were as follows: (1) It was experimentally confirmed that the slope gentleness and the decrease of the top elevation of the armoured embankment induced by the earthquake did not lead to the increase of the overtopping discharge by the waves after the earthquake. (2) Subsidence and lateral displacement at the top of the parapet of the seawall caused by the S2 scale earthquake were approximately 0.12 m-0.2 m and 0.18 m-0.6 m respectively under the condition that the thickness of the sand seabed was 10 m and relative density was 60%. (3) Even though such displacements were induced at the top of the parapet of the seawall, seismic performance of the seawall against the large waves was kept after the earthquake. (author)

  14. Ecological implications of extreme events: footprints of the 2010 earthquake along the Chilean coast.

    Directory of Open Access Journals (Sweden)

    Eduardo Jaramillo

    Full Text Available Deciphering ecological effects of major catastrophic events such as earthquakes, tsunamis, volcanic eruptions, storms and fires, requires rapid interdisciplinary efforts often hampered by a lack of pre-event data. Using results of intertidal surveys conducted shortly before and immediately after Chile's 2010 M(w 8.8 earthquake along the entire rupture zone (ca. 34-38°S, we provide the first quantification of earthquake and tsunami effects on sandy beach ecosystems. Our study incorporated anthropogenic coastal development as a key design factor. Ecological responses of beach ecosystems were strongly affected by the magnitude of land-level change. Subsidence along the northern rupture segment combined with tsunami-associated disturbance and drowned beaches. In contrast, along the co-seismically uplifted southern rupture, beaches widened and flattened increasing habitat availability. Post-event changes in abundance and distribution of mobile intertidal invertebrates were not uniform, varying with land-level change, tsunami height and coastal development. On beaches where subsidence occurred, intertidal zones and their associated species disappeared. On some beaches, uplift of rocky sub-tidal substrate eliminated low intertidal sand beach habitat for ecologically important species. On others, unexpected interactions of uplift with man-made coastal armouring included restoration of upper and mid-intertidal habitat seaward of armouring followed by rapid colonization of mobile crustaceans typical of these zones formerly excluded by constraints imposed by the armouring structures. Responses of coastal ecosystems to major earthquakes appear to vary strongly with land-level change, the mobility of the biota and shore type. Our results show that interactions of extreme events with human-altered shorelines can produce surprising ecological outcomes, and suggest these complex responses to landscape alteration can leave lasting footprints in coastal

  15. Effects of B4C addition on the micro- structural and thermal properties of hot pressed SiC ceramic matrix composites

    Directory of Open Access Journals (Sweden)

    Z. Keçeli

    2009-12-01

    Full Text Available Purpose: The purpose of paper is to evaluate effects of B4C addition on the microstructural and thermal properties of hot pressed SiC ceramic matrix composites.Design/methodology/approach: The effect of B4C addition on microstructural and thermal properties of the SiC-B4C powder composites were investigated after high energy milling and hot pressing. SiC powders containing 5wt%, 10wt%, 15wt% B4C were mechanically alloyed in a high energy ball mill for 8 h.Findings: Microstructural characterisation investigations (SEM, XRD were carried out on mechanically alloyed SiC powder composites containing 5 wt %, 10 wt %, 15 wt % B4C powders and on these powder composites sintered in vacuum at 50 MPa at 2100ºC. The thermal properties were characterised using DTA, TGA and dilatometer. The results were evaluated.Research limitations/implications: In this study, the effect of B4C addition on microstructural and mechanical properties of the SiC-B4C powder composites was investigated after high energy milling and hot pressing.Originality/value: Ceramic matrix composite (CMC material systems are stimulating a lot of interest to be used and provide unique properties for aircraft and land-based turbine engines, defence applications, rocket motors, aerospace hot structures and industrial applications. Boron carbide (B4C-silicon carbide (SiC ceramic composites are very promising armour materials because they are intrinsically very hard. Advanced SiC-based armour is desired so that the projectile is completely defeated without penetrating the ceramic armour.

  16. Optimization of armored fighting vehicle crew performance in a net-centric battlefield

    Science.gov (United States)

    McKeen, William P.; Espenant, Mark

    2002-08-01

    Traditional display, control and situational awareness technologies may not allow the fighting vehicle commander to take full advantage of the rich data environment made available in the net-centric battle field of the future. Indeed, the sheer complexity and volume of available data, if not properly managed, may actually reduce crew performance by overloading or confusing the commander with irrelevant information. New techniques must be explored to understand how to present battlefield information and provide the commander with continuous high quality situational awareness without significant cognitive overhead. Control of the vehicle's many complex systems must also be addressed the entire Soldier Machine Interface must be optimized if we are to realize the potential performance improvements. Defence Research and Development Canada (DRDC) and General Dynamics Canada Ltd. have embarked on a joint program called Future Armoured Fighting Vehicle Systems Technology Demonstrator, to explore these issues. The project is based on man-in-the-loop experimentation using virtual reality technology on a six degree-of-freedom motion platform that simulates the motion, sights and sounds inside a future armoured vehicle. The vehicle commander is provided with a virtual reality vision system to view a simulated 360 degree multi-spectrum representation of the battlespace, thus providing enhanced situational awareness. Graphic overlays with decision aid information will be added to reduce cognitive loading. Experiments will be conducted to evaluate the effectiveness of virtual control systems. The simulations are carried out in a virtual battlefield created by linking our simulation system with other simulation centers to provide a net-centric battlespace where enemy forces can be engaged in fire fights. Survivability and lethality will be measured in successive test sequences using real armoured fighting vehicle crews to optimize overall system effectiveness.

  17. Erosion processes acting in semi-arid climate zone of the Ebro Basin (Bardenas Reales, NE of Spain); Procesos de erosion actuantes en una zona de clima semiarido de la Depresion del Ebro (Bardenas Reales, NE de Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Marin, C.; Desir, G.

    2009-07-01

    Bardenas Reales is an erosive depression located in the central-western part of the Ebro Depression. May different erosion processes act on this zone: gullying, piping, mud slides and armoured mud balls among others that contribute to export great quantity of material outside the basin. Depending on lithology and physico-chemical properties erosion acting processes differ. The knowledge of that processes help us to understand the great amount of soil loss that take place on the studied zone, bigger than those recommended. (Author) 8 refs.

  18. Damage pattern and damage progression on breakwater roundheads under multidirectional waves

    DEFF Research Database (Denmark)

    Comola, F.; Andersen, Thomas Lykke; Martinelli, L.;

    2014-01-01

    An experimental model test study is carried out to investigate damage pattern and progression on a rock armoured breakwater roundhead subjected to multidirectional waves. Concerning damage pattern, the most critical sector is observed to shift leeward with increasing wave period. Taking angles...... characteristics. The damage progression is observed dependent on significant wave height and peak wave period, but not on the directional spreading and the spectral width of the incident waves. Combining the results of both damage pattern and damage progression, a stability formula for the distribution of damage...

  19. THE SPRINGBOK SIXTH DIVISION

    Directory of Open Access Journals (Sweden)

    Hertzog Biermann

    2012-02-01

    Full Text Available The Springbok Sixth Division was a mighty armoured force Of men whose ancestors made war in ships, on foot and horse They wrote a stirring chapter in Springbok Martial lore When they went to sunny Italy in Nineteen-Forty-Four.   They were in the Springbok First Team and their modest claim to fame Was their response to the clarion call: "Pay up and play the game!" Their duty they did nobly as their fathers did of old They proudly wore the Sixth Div flash of Springbok green and gold.

  20. The laws of software process a new model for the production and management of software

    CERN Document Server

    Armour, Phillip G

    2003-01-01

    The Nature of Software and The Laws of Software ProcessA Brief History of KnowledgeThe Characteristics of Knowledge Storage MediaThe Nature of Software DevelopmentThe Laws of Software Process and the Five Orders of IgnoranceThe Laws of Software ProcessThe First Law of Software ProcessThe Corollary to the First Law of Software ProcessThe Reflexive Creation of Systems and ProcessesThe Lemma of Eternal LatenessThe Second Law of Software ProcessThe Rule of Process BifurcationThe Dual Hypotheses of Knowledge DiscoveryArmour's Observation on Software ProcessThe Third Law of Software Process (also kn

  1. Network based multi-channel digital flash X-ray imaging system

    International Nuclear Information System (INIS)

    A network based multi-channel digital flash X-ray imaging system has been developed. It can be used to acquire and digitize orthogonal flash X-ray images in multi-interval, and to distribute the images on the network. There is no need of films and chemical process, no anxiety of waiting and no trouble of film archiving. This system is useful for testing ballistics, jet, explode, armour-piercing and fast running machines. The system composing and acquired images of terminal ballistics are presented. The software for object separating, profile calculating and 3D cavity reconstruction are described

  2. Environment and Economy: joined at the hip or just strange bedfellows?

    OpenAIRE

    Runnalls, David

    2011-01-01

    In the aftermath of the financial crisis, we have seen a flurry of new books and publications on the need for reform of the international financial system to make it more resilient, transparent and less subject to the “too big to fail” shocks which brought us to the brink of economic ruin. Basel 2 and the increased role of the G-20 come within this ambit. The crack in the armour of economic infallibility has created policy space for a number of other discussions for fundamental reform of the ...

  3. Design of Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, H. F.

    1992-01-01

    Rubble mound breakwaters require availability of often very large quantities of rock materials of various gradings and qualities. Because natural stones are seldom available in sufficient quantities and sizes the materials must in most cases be supplied from quarries. The output from a quarry in...... construction stage. Anyway, it is seldom that a fair amount of rocks of mass larger than 10-15 t can be produced, even in good quality quarries. If heavier blocks are needed concrete armour units or vertical structures must be considered....

  4. Shark skin: a function in feeding.

    OpenAIRE

    Southall, E J; Sims, D.W.

    2003-01-01

    Dermal denticles are unique tooth-like structures embedded in the skin of sharks and rays that protect them from predators and ectoparasites, reduce mechanical abrasion and possibly minimize swimming-induced drag. Here, we show that juvenile lesser spotted dogfish (Scyliorhinus canicula) also use this body armour to anchor food items near their tail so that bite-sized pieces can be torn away by rapid jaw and head movements. This scale-rasp behaviour is novel among fishes and suggests a new ro...

  5. Determining the level of usage of information systems in selected small businesses / Pieter Botha

    OpenAIRE

    Botha, Pieter Andries

    2011-01-01

    When starting a new business, the owner has the vision to grow the business to a large corporate enterprise. In the small business stage, many challenges face the management of such businesses though. The influence of the external environment pushes the business from one side to the other. It is at this point where a true entrepreneur takes control and uses all necessary skills to succeed in generating the expected return on the invested money. One of the skills in the management armour of...

  6. AIR / SEA RESCUE LAUNCHES

    Directory of Open Access Journals (Sweden)

    W.H. Rice

    2012-02-01

    Full Text Available The Motor Boat Wing of the South African Air Force was inaugurated some thirty eight years ago.With its main base at Gordon's Bay, the wing was formed to operate the various marine craft used to provide a service to the flying component of the South African Air Force. Its main function was to be air/sea rescue, but it also had to man and maintain armoured target boats, seaplane tenders, marine tenders and the 'bomb scows', used for recovering practise bombs and missiles and for laying and lifting moorings.

  7. Degradation and defects in plasma facing components for future fusion devices

    OpenAIRE

    Kapustina, Anna

    2004-01-01

    The main function of the first wall and the divertor are to remove the power generated by the plasma and to shield from neutrons. The plasma facing components (PFCs) are optimised the high heat flux energy removal. PFCs are composed of a thick armour joined to an actively cooled heat sink to provide the necessary transfer of the incident power to the cooling system. During normal operation these components have to dissipate a heat flux up to 5 MW/m² in the divertor and 0.5 MW/m² on the first ...

  8. Simulating effectiveness of helicopter evasive manoeuvres to RPG attack

    Science.gov (United States)

    Anderson, D.; Thomson, D. G.

    2010-04-01

    The survivability of helicopters under attack by ground troops using rocket propelled grenades has been amply illustrated over the past decade. Given that an RPG is unguided and it is infeasible to cover helicopters in thick armour, existing optical countermeasures are ineffective - the solution is to compute an evasive manoeuvre. In this paper, an RPG/helicopter engagement model is presented. Manoeuvre profiles are defined in the missile approach warning sensor camera image plane using a local maximum acceleration vector. Required control inputs are then computed using inverse simulation techniques. Assessments of platform survivability to several engagement scenarios are presented.

  9. Parameters Influencing Wave Run-Up on a Rubble Mound Breakwater

    DEFF Research Database (Denmark)

    Walle, Björn Van de; Rouck, Julien De; Damme, Luc Van;

    2002-01-01

    Full scale wave run-up measurements have been performed on the Zebrugge rubble mound breakwater. Wave run-up also has been investigated on various small scale models of the Zeebrugge breakwater. A significant difference between the results has been noticed. Additional small scale model testing has...... been carried out on a slightly modified scale model: a regular armour unit pattern has been applied in stead of an irregular pattern as in full scale. The aim of the additional laboratory tests was to investigate the influence of the spectral width parameter and the influence of the position of the...

  10. Empirical Formulae for Breakage of Dolosse and Tetrapods

    DEFF Research Database (Denmark)

    Burcharth, H. F.; d'Angremond, K.; Meer, W. van der;

    2000-01-01

    the hydraulic stability (resistance to displacements) of the armour layers. Breakage occurs when the stresses from the static, pulsating and impact loads exceeds the tensile strength of the concrete. While the hydraulic stability can be studied in Froude-scale hydraulic model tests, it is not possible....... The paper presents a simple dimensional empirical formula instead of diagrams for the estimation of the number of broken Dolosse and Tetrapods in prototype situations, because probabilistic design of breakwaters requires failure mode formulae with the associated uncertainties....

  11. Bullet dents – “Proof marks” or battle damage

    OpenAIRE

    Williams, Alan; Edge, David; Atkins, Tony

    2006-01-01

    It is well known that the breastplates of many armours from the later 16th century and the 17th century bear the hemispherical dents generally known as proof marks. It has been taken as axiomatic that these marks were made in order to d...

  12. Network based multi-channel digital flash X-ray imaging system

    International Nuclear Information System (INIS)

    A network based multi-channel digital flash X-ray imaging system has been developed. It can be used to acquire and digitize orthogonal flash X-ray images in multi-interval, and to distribute the images on the network. There is no need of films and chemical process, no anxiety of waiting and no trouble of film archiving. This system is useful for testing ballistics, jet, explode, armour-piercing and fast running machines. The system composing and acquired images are presented. The software for object separating, mass calculating, 3D positioning, speed determining and cavity reconstruction are described

  13. Erosion processes acting in semi-arid climate zone of the Ebro Basin (Bardenas Reales, NE of Spain)

    International Nuclear Information System (INIS)

    Bardenas Reales is an erosive depression located in the central-western part of the Ebro Depression. May different erosion processes act on this zone: gullying, piping, mud slides and armoured mud balls among others that contribute to export great quantity of material outside the basin. Depending on lithology and physico-chemical properties erosion acting processes differ. The knowledge of that processes help us to understand the great amount of soil loss that take place on the studied zone, bigger than those recommended. (Author) 8 refs.

  14. Chemical aspects of antiballistic cermets preparation

    Czech Academy of Sciences Publication Activity Database

    Brožek, Vlastimil; Kubatík, Tomáš František; Chráska, Tomáš; Mušálek, Radek; Janata, Marek; Mastný, L.

    Prague: Czech Society of Industrial Chemistry, 2015 - (Kalenda, P.; Lubojacký, J.), s. 218-224. (ICCT). ISBN 978-80-86238-79-1. [International Conference on Chemical Technology-ICCT2015/3./. Mikulov (CZ), 13.04.2015-15.04.2015] R&D Projects: GA MPO FR-TI2/702 Institutional support: RVO:61389021 Keywords : Anti-ballistic ceramics * armour ceramics * plasma spraying * titanium boride * plasma spraying * titanium nitride Subject RIV: CA - Inorganic Chemistry http://www.amca.cz/icct/Full_Papers_ICCT_2015_web.pdf

  15. Problems of building social and production bases for the construction of the Temelin nuclear power plant

    International Nuclear Information System (INIS)

    A survey is given of capital costs of building parts and the concept is presented of the equipment of a building site. The social basis consists of accommodation units, cloakrooms, catering units, utility units, a health care centre and a shopping centre. The production base consists of a central concrete plant, cement plant, central armour unit, forming hall, storage area, buildings for pre-assembly, fleet of trucks and other machines, maintenance and repair shops. The network infrastructure and the mains connections are designed and the procedure of the build up of the site is described. The experience is summed up and recommendations made for future nuclear power plant projects. (E.S.)

  16. Assessment of exposure to scattered radiation in interventional procedures using special protective bismuth; Evaluacion de la exposicion a radiacion dispersa en procedimientos intervencionistas usando protectores especiales de bismuto

    Energy Technology Data Exchange (ETDEWEB)

    Soto Bua, M.; Medina Jimenez, E.; Vazquez Vazquez, R.; Santamaria Vazquez, F.; Otero Martinez, C.; Lobato Busto, R.; Luna Vega, V.; Mosquera Suero, J.; Sanchez Garcia, M.; Pombar Camean, M.

    2011-07-01

    There are currently marketed specific producta aimed at reducing personnel exposure to radiation scattered in cardiac catheterization procedures, interventional radiology or electrophysiology. Our service has been proposed to study the attenuation characteristics of the product Drape Armour manufactured by the company Microtek. Is a flexible devices constructed from an alloy of bismuth and sterility characteristics and infection control and fluid makes them particularly suitable for incorporating into the operative field of the patient. To study their behavior, there have been staff dose measurements representative of the moaL common situations of exposure to scattered radiation in a typical procedure of intervention.

  17. The Effect of Wave Grouping on On-Shore Structures

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    1979-01-01

    generated solely in accordance with an energy spectrum obtained from field data can be used. To investigate the importance of the succession of waves to the impact on coastal structures, run-up/down on permeable and impermeable slopes and stability of dolos armour were investigated in model tests by using...... three different wave patterns. A significant influence of the succession of waves is demonstrated. A jump in wave height seems to be a very important wave pattern which should be included in the analysis of wave grouping. Also the importance of wave period and wave steepness to the relative run...

  18. Simulated Afghan Towns: US Military Training Grounds Germany

    OpenAIRE

    Clonan, Tom

    2010-01-01

    Spin Boldoz is an Afghan town in Kandahar province close to the border with Pakistan. As we approach the town – with the US 2nd Cavalry Stryker Regiment – the town’s market square is teeming with Afghan civilians haggling over stalls of fruit and vegetables. Smoke from cooking fires and braziers mix with the diesel exhaust of the Stryker Brigade’s armoured vehicles. Donkeys, goats and sheep are tethered and ready for sale. The regiment’s radios are humming with chatter and overhead an u...

  19. Chapter 1. General information about uranium. 1.10. Uranium application

    International Nuclear Information System (INIS)

    Full text: Metallic uranium or its compounds are used as nuclear fuel in nuclear reactors. A natural or low-enriched admixture of uranium isotopes is applied in stationery reactors of nuclear power plants, and products of a high enrichment degree are used in nuclear power plants or in reactors that operates with fast neutrons. 235U is a source of nuclear energy in nuclear weapons. Depleted uranium is used as armour-piercing core in bombshells. 238U serves as a source of secondary nuclear fuel - plutonium. (author)

  20. Optimum Safety Levels and Design Rules for the Icelandic-Type Berm Breakwater

    DEFF Research Database (Denmark)

    Sigurdarson, Sigurdur; van der Meer, Jentsje W.; Burcharth, Hans F.;

    2009-01-01

    strategies and possible failure with corresponding downtime have been taken into account, as well as actual market prices (in Iceland and Norway) for rack material and construction. Calculations show that low stability numbers for the largest rock armour layer give the optimal safety level.......This paper gives first an elaboration of berm recession equations for berm breakwaters and then new deterministic design rules for the Icelandic-type berm breakwater. Safety optimization calculations have been performed for a mild depth limited wave climate and for a situation a deep water. Repair...

  1. The good, the bad and the ugly, part II.

    Science.gov (United States)

    Dubin, C S

    1995-04-01

    The author provides a second installment to a previous column in which he wrote about the settlement proposal offered by Baxter and Armour and how it demonstrated industry's lack of respect for the hemophilia/HIV community. The author now argues that the courts have shown a less than exemplary track record in helping those who suffer as a result of government or multinational corporation actions, and this record continues. Despite feelings from some in the hemophiliac community that a concerted effort to obtain justice would backfire and harm the community, The Committee of Ten Thousand (COTT) persevered and has gotten a class action suit before the court. PMID:11362349

  2. Upgrade of Coastal Defence Structures Against Increased Loadings Caused by Climate Change

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke; Lara, Javier L.

    2014-01-01

    The paper presents a design exercise of upgrading a typical rock armoured revetment by modifying the structure profile and adding structure elements. Several concepts of upgrading are examined. A sea level rise corresponding to the mean of the IPCC 2007 predictions is used together with a slight...... increase in long-term wind/wave conditions as predicted for the North Sea by the Danish Coastal Authority. Both conditions of non-acceptable and acceptable increase in structure crest level are considered. Moreover, a scenario for steepening of the foreshore due to morphological changes caused by increased...

  3. Inconsistent Performance of a Tandem-shaped Charge Warhead

    Directory of Open Access Journals (Sweden)

    S. Harikrishnan

    2010-03-01

    Full Text Available Tandem shaped charge warhead is one of the efficient methods to defeat the explosive reactive armour (ERA protected main battle tanks (MBT. In this concept, two shaped charges mounted in the same missile are initiated one after the other with certain time delay. First shaped charge jet would remove the ERA and the second jet would penetrate the bare armour. Both these explosive charges are mounted close to each other most of the time due to severe space constraints in the system. It is necessary to protect the second charge from the blast effects of first charge, during the time delay between the initiations of two charges. Blast effect of precursor charge on main charge is understood to have detrimental effects on the performance of warhead system.This paper presents a case study of an investigation into the inconsistent performance of a tandem warhead for a third generation antitank missile. The warhead generated a crooked jet resulting in inconsistent penetration performance. Typical crater profiles were observed when the penetration performance deteriorated. Systematic analysis was carried out and simulations were performed using Autodyn-3D to reproduce the phenomenon. Experiments were conducted using Flash X-ray which substantiated the assumptions made for simulation studies.Defence Science Journal, 2010, 60(2, pp.164-168, DOI:http://dx.doi.org/10.14429/dsj.60.335

  4. RACLETTE: a model for evaluating the thermal response of plasma facing components to slow high power plasma transients. Pt. II. Analysis of ITER plasma facing components

    International Nuclear Information System (INIS)

    For pt.I see ibid., p.85-100, 1997. The transient thermal model RACLETTE (acronym of Rate Analysis Code for pLasma Energy Transfer Transient Evaluation) described in part I of this paper is applied here to analyse the heat transfer and erosion effects of various slow (100 ms-10 s) high power energy transients on the actively cooled plasma facing components (PFCs) of the International Thermonuclear Experimental Reactor (ITER). These have a strong bearing on the PFC design and need careful analysis. The relevant parameters affecting the heat transfer during the plasma excursions are established. The temperature variation with time and space is evaluated together with the extent of vaporisation and melting (the latter only for metals) for the different candidate armour materials considered for the design (i.e., Be for the primary first wall, Be and CFCs for the limiter, Be, W, and CFCs for the divertor plates) and including for certain cases low-density vapour shielding effects. The critical heat flux, the change of the coolant parameters and the possible severe degradation of the coolant heat removal capability that could result under certain conditions during these transients, for example for the limiter, are also evaluated. Based on the results, the design implications on the heat removal performance and erosion damage of the various ITER PFCs are critically discussed and some recommendations are made for the selection of the most adequate protection materials and optimum armour thickness. (orig.)

  5. RACLETTE: a model for evaluating the thermal response of plasma facing components to slow high power plasma transients. Part II: Analysis of ITER plasma facing components

    Science.gov (United States)

    Federici, Gianfranco; Raffray, A. René

    1997-04-01

    The transient thermal model RACLETTE (acronym of Rate Analysis Code for pLasma Energy Transfer Transient Evaluation) described in part I of this paper is applied here to analyse the heat transfer and erosion effects of various slow (100 ms-10 s) high power energy transients on the actively cooled plasma facing components (PFCs) of the International Thermonuclear Experimental Reactor (ITER). These have a strong bearing on the PFC design and need careful analysis. The relevant parameters affecting the heat transfer during the plasma excursions are established. The temperature variation with time and space is evaluated together with the extent of vaporisation and melting (the latter only for metals) for the different candidate armour materials considered for the design (i.e., Be for the primary first wall, Be and CFCs for the limiter, Be, W, and CFCs for the divertor plates) and including for certain cases low-density vapour shielding effects. The critical heat flux, the change of the coolant parameters and the possible severe degradation of the coolant heat removal capability that could result under certain conditions during these transients, for example for the limiter, are also evaluated. Based on the results, the design implications on the heat removal performance and erosion damage of the variuos ITER PFCs are critically discussed and some recommendations are made for the selection of the most adequate protection materials and optimum armour thickness.

  6. In-vessel tritium retention and removal in ITER-FEAT

    International Nuclear Information System (INIS)

    Erosion of the divertor and first-wall plasma-facing components, tritium uptake in the re-deposited films, and direct implantation in the armour material surfaces surrounding the plasma, represent crucial physical issues that affect the design of future fusion devices. In this paper we present the derivation, and discuss the results, of current predictions of tritium inventory in ITER-FEAT due to co-deposition and implantation and their attendant uncertainties. The current armour materials proposed for ITER-FEAT are beryllium on the first-wall, carbon-fibre-composites on the divertor plate near the separatrix strike points, to withstand the high thermal loads expected during off-normal events, e.g., disruption, and tungsten elsewhere in the divertor. Tritium co-deposition with chemically eroded carbon in the divertor, and possibly with some Be eroded from the first-wall, is expected to represent the dominant mechanism of in-vessel tritium retention in ITER-FEAT. This demands efficient in-situ methods of mitigation and retrieval to avoid frequent outages due to the reaching of precautionary operating limits set by safety considerations (e.g., ∝350 g of in-vessel co-deposited tritium) and for fuel economy reasons. Priority areas where further R and D work is required to narrow the remaining uncertainties are also briefly discussed. (orig.)

  7. Aging the oldest turtles: the placodont affinities of Priscochelys hegnabrunnensis

    Science.gov (United States)

    Scheyer, Torsten M.

    2008-09-01

    Priscochelys hegnabrunnensis, a fragmentary piece of armour shell from the Muschelkalk of Germany (Upper Triassic) with few diagnostic morphological features, was recently proposed to represent the oldest known stem turtle. As such, the specimen is of high importance because it shifts the date of the first appearance of turtles back about 20 Ma, which equals about 10% of the total stratigraphic range of the group. In this paper, I present new morphologic, histologic and neutron tomographic (NT) data that relate to the microstructure of the bone of the specimen itself. In opposition to the previous morphologic descriptions, P. hegnabrunnensis was found to share several distinctive features (i.e. bone sutures congruent with scute sulci, absence of a diploe structure with interior cancellous bone, thin vascular canals radiating outwards from distinct centres in each field and rugose ventral bone surface texture consisting of mineralised fibre bundles) with cyamodontoid placodonts (Diapsida: Sauropterygia) and fewer with stem turtles (i.e. depth of sulci). Two aspects that were previously thought to be relevant for the assignment to the turtle stem (conical scutes and presence of foramina) are argued to be of dubious value. P. hegnabrunnensis is proposed to represent a fragmentary piece of cyamodontoid armour consisting of fused conical plates herein. The specimen is not a part of the turtle stem and thus does not represent the oldest turtle. Accordingly, P. hegnabrunnensis does not shorten the ghost lineage to the potential sister group of turtles.

  8. Damage of actively cooled plasma facing components of magnetic confinement controlled fusion machines

    Energy Technology Data Exchange (ETDEWEB)

    Chevet, G. [Association Euratom-CEA, DSM/DRFC, CEA Cadarache, Saint-Paul-Lez-Durance (France)], E-mail: gaelle.chevet@cea.fr; Schlosser, J. [Association Euratom-CEA, DSM/DRFC, CEA Cadarache, Saint-Paul-Lez-Durance (France); Martin, E.; Herb, V.; Camus, G. [Universite Bordeaux 1, UMR 5801 (CNRS-SAFRAN-CEA-UB1), Laboratoire des Composites Thermostructuraux, F-33600 Pessac (France)

    2009-03-31

    Plasma facing components (PFCs) of magnetic fusion machines have high manufactured residual stresses and have to withstand important stress ranges during operation. These actively cooled PFCs have a carbon fibre composite (CFC) armour and a copper alloy heat sink. Cracks mainly appear in the CFC near the composite/copper interface. In order to analyse damage mechanisms, it is important to well simulate the damage mechanisms both of the CFC and the CFC/Cu interface. This study focuses on the mechanical behaviour of the N11 material for which the scalar ONERA damage model was used. The damage parameters of this model were identified by similarity to a neighbour material, which was extensively analysed, according to the few characterization test results available for the N11. The finite elements calculations predict a high level of damage of the CFC at the interface zone explaining the encountered difficulties in the PFCs fabrication. These results suggest that the damage state of the CFC cells is correlated with a conductivity decrease to explain the temperature increase of the armour surface under fatigue heat load.

  9. Effective Thermal Conductivity of Graphite Materials with Cracks

    International Nuclear Information System (INIS)

    The dependence of effective thermal diffusivity on temperature caused by volumetric cracks is modelled for macroscopic graphite samples using the three-dimensional thermomechanics code Pegasus-3D. At high off-normal heat loads typical of the divertor armour, thermostress due to the anisotropy of graphite grains is much larger than that due to the temperature gradient. Numerical simulation demonstrated that the volumetric crack density both in fine grain graphites and in the CFC matrix depends mainly on the local sample temperature, not on the temperature gradient. This allows to define an effective thermal diffusivity for graphite with cracks. The results obtained are used to explain intense cracking and particle release from carbon based materials under electron beam heat load. Decrease of graphite thermal diffusivity with increase of the crack density explains particle release mechanism in the experiments with CFC where a clear energy threshold for the onset of particle release has been observed. Surface temperature measurement is necessary to calibrate the Pegasus-3D code for simulation of ITER divertor armour brittle destruction

  10. THE INFLUENCE OF GEOLOGY ON THE COURSE AND OUTCOME OF THE THIRD BATTLE OF YPRES (FLANDERS, WW1

    Directory of Open Access Journals (Sweden)

    Marko Zečević

    2016-02-01

    Full Text Available Geological structure of the terrain as a ground for a battlefield could be a significant factor for the success or failure of a military operation. The geology of the Belgian town of Ypres was an important, maybe even crucial factor, of the failure of the WWI Allied Powers offensive military operations against German Axis forces in 1917. The Early Eocene clays found at the ground surface at Ypres, coupled with excess precipitation, turned out to be utterly inappropriate for the fortification, movement, fighting and manoeuvring of all military units, especially the armoured units that were directed towards hardly passable routes. With selecting the unsuitable and hardly passable terrain, that is the direction of the attack, the British army had losses of the available combat potential and armoured forces were ineffective during the battle. The total number of Allied casualties was 448,000 dead, wounded, imprisoned and missing. This paper offers other possible solutions that would, from a military geographic and military geological viewpoint, have made a better solution for achieving the strategic goal required by the Allies on the eve of the Third Battle of Ypres in 1917.

  11. Characterization and damaging law of CFC for high heat flux actively cooled plasma facing components

    Science.gov (United States)

    Chevet, G.; Martin, E.; Boscary, J.; Camus, G.; Herb, V.; Schlosser, J.; Escourbiac, F.; Missirlian, M.

    2011-10-01

    The carbon fiber reinforced carbon composite (CFC) Sepcarb N11 has been used in the Tore Supra (TS) tokamak (Cadarache, France) as armour material for the plasma facing components. For the fabrication of the Wendelstein 7-X (W7-X) divertor (Greifswald, Germany), the NB31 material was chosen. For the fabrication of the ITER divertor, two potential CFC candidates are the NB31 and NB41 materials. In the case of Tore Supra, defects such as microcracks or debonding were found at the interface between CFC tile and copper heat sink. A mechanical characterization of the behaviour of N11 and NB31 was undertaken, allowing the identification of a damage model and finite element calculations both for flat tiles (TS and W7-X) and monoblock (ITER) armours. The mechanical responses of these CFC materials were found almost linear under on-axis tensile tests but highly nonlinear under shear tests or off-axis tensile tests. As a consequence, damage develops within the high shear-stress zones.

  12. Results and analysis of high heat flux tests on a full scale vertical target prototype of ITER divertor

    International Nuclear Information System (INIS)

    After an extensive development program, a Full-Scale Divertor Target prototype (VTFS) manufactured with all the main features of the corresponding ITER divertor, was intensively tested in the high heat flux FE200 facility. The prototype consists of four units having a full mono-block geometry. The lower part (CFC armour) and the upper part (W armour) of each mono-block were joined to the solution annealed, quenched and cold worked CuCrZr tube by HIP technique. The CFC mono-block was successfully tested up to 1000 cycles at 23 MW/m2 without any indication of failure. This value is well beyond the ITER design target of 300 cycles at 20 MW/m2. The W mono-block endured ∼600 cycles at 10 MW/m2. This value of flux is one order of magnitude higher than the ITER design target for the upper part of the vertical target. Fatigue damage is observed when pursuing the cycling up to 15 MW/m2. A first stress analysis seems to predict these factual results. However, macro-graphic examinations should bring a better damage valuation. Meanwhile, the fatigue testing will continue on the W healthy part of the VTFS prototype with castellation located on the heated surface (reducing the stresses close to the W-Cu interface). (authors)

  13. RACLETTE: a model for evaluating the thermal response of plasma facing components to slow high power plasma transients. Part I: Theory and description of model capabilities

    Science.gov (United States)

    Raffray, A. René; Federici, Gianfranco

    1997-04-01

    RACLETTE (Rate Analysis Code for pLasma Energy Transfer Transient Evaluation), a comprehensive but relatively simple and versatile model, was developed to help in the design analysis of plasma facing components (PFCs) under 'slow' high power transients, such as those associated with plasma vertical displacement events. The model includes all the key surface heat transfer processes such as evaporation, melting, and radiation, and their interaction with the PFC block thermal response and the coolant behaviour. This paper represents part I of two sister and complementary papers. It covers the model description, calibration and validation, and presents a number of parametric analyses shedding light on and identifying trends in the PFC armour block response to high plasma energy deposition transients. Parameters investigated include the plasma energy density and deposition time, the armour thickness and the presence of vapour shielding effects. Part II of the paper focuses on specific design analyses of ITER plasma facing components (divertor, limiter, primary first wall and baffle), including improvements in the thermal-hydraulic modeling required for better understanding the consequences of high energy deposition transients in particular for the ITER limiter case.

  14. High velocity impact on different hybrid architectures of 2D laminated and 3D warp interlock fabric composite

    Directory of Open Access Journals (Sweden)

    Vallee D.

    2012-08-01

    Full Text Available For decades, conventional amour shield is mainly oriented on metallic materials which are today well-known. Since the use of non conventional threats as IEDs, performances of those protections are required to be upgraded. The expected improvements that manufacturers are looking for are mainly oriented to the weight reduction which is the key parameter to reduce the fuel consumption, increase the payload, and offer more manoeuvrability to vehicles [1]. However, the difficulty is to reduce as cautiously as possible the total mass of the protection solution while ensuring the safety of the vehicle. One of the possible solutions is to use new combinations of materials, able to be more efficient against new threats and lighter than the traditional steel armour. It is in this context that the combination between some well-known ballistic alloys and textile composite material appear as a high potential solution for armour plated protection. Indeed, used as a backing, textile composite material present some interesting properties such as a very low density compared with steel and good behaviour in term of ballistic efficiency. This study proposes to test and compare the behaviour and efficiency of three different textile composite backings.

  15. Grainsize Patterns and Bed Evolution of the Rhone River (France): A Present-day Snapshot Following a Century and a Half of Human Modifications

    Science.gov (United States)

    Michal, T.; Parrot, E.; Piegay, H.

    2014-12-01

    Over the past 150 years the Rhône River has been heavily altered by human infrastructures. The first wave (1860 - 1930) of modifications consisted of dikes and groynes designed to narrow the channel and promote incision in order to facilitate navigation. A second period (1948 - 1986) involved the construction of a series of canals and dams for hydroelectricity production. These works bypass multiple reaches of the original channel and drastically reduce the discharge and sediment load reaching them. A comprehensive study underway is aimed at describing the present-day morphology of the Rhone along its 512 km length from its source at Lake Geneva to its sink at the Mediterranean Sea and quantifying the role of management works in the evolution to its current state. Grainsize distributions and armour ratios were determined using a combination of Wolman counts on bars and in shallow channels and dredge samples collected from a boat in navigable reaches. Long profiles were constructed from historical bathymetric maps and bathymetric data collected between 1950 - 2010. Differential long profiles highlighting changes in bed elevation due to sediment storage and erosion were analyzed for three different periods: post-channelization, post-dam construction, and a recent period of major floods. Results show a complex discontinuous pattern in grainsize associated with hydraulic discontinuities imposed by dams. The D50 for bypass reaches is 45 mm compared to a D50 of 34 mm in the non-bypass reaches. The lower D50 as well as a finer tailed distribution in non-bypass reaches reflects fining associated with storage upstream of dams. Armour ratios are on average around 2 but are notably higher for reaches in the middle section of the Rhone. The average incision rate was 1.8 cm/yr for the period of post-channelization and 1.2 cm/yr following dam construction, suggesting the post-dam Rhone was already partially armoured due to incision associated with channelization preceding dam

  16. Wave boundary layer over a stone-covered bed

    DEFF Research Database (Denmark)

    Dixen, Martin; Hatipoglu, Figen; Sumer, B. Mutlu;

    2008-01-01

    This paper summarizes the results of an experimental investigation on wave boundary layers over a bed with large roughness, simulating stone/rock/armour block cover on the sea bottom. The roughness elements used in the experiments were stones the size of 1.4cm and 3.85cm in one group of experiments...... ping-pong ball experiments to study the influence of packing pattern, packing density, number of layers and surface roughness of the roughness elements. The results show that the friction factor seems to be not extremely sensitive to these factors. The results also show that the friction factor for...... extremely sensitive to the packing pattern, the packing density, the number of layers and the surface roughness of the roughness elements. There exists a steady streaming near the bed in the direction of wave propagation, in agreement with the existing work. The present data indicate that the steady...

  17. Geant4 calculations for space radiation shielding material Al2O3

    Science.gov (United States)

    Capali, Veli; Acar Yesil, Tolga; Kaya, Gokhan; Kaplan, Abdullah; Yavuz, Mustafa; Tilki, Tahir

    2015-07-01

    Aluminium Oxide, Al2O3 is the most widely used material in the engineering applications. It is significant aluminium metal, because of its hardness and as a refractory material owing to its high melting point. This material has several engineering applications in diverse fields such as, ballistic armour systems, wear components, electrical and electronic substrates, automotive parts, components for electric industry and aero-engine. As well, it is used as a dosimeter for radiation protection and therapy applications for its optically stimulated luminescence properties. In this study, stopping powers and penetrating distances have been calculated for the alpha, proton, electron and gamma particles in space radiation shielding material Al2O3 for incident energies 1 keV - 1 GeV using GEANT4 calculation code.

  18. Beryllium for fusion application - recent results

    Science.gov (United States)

    Khomutov, A.; Barabash, V.; Chakin, V.; Chernov, V.; Davydov, D.; Gorokhov, V.; Kawamura, H.; Kolbasov, B.; Kupriyanov, I.; Longhurst, G.; Scaffidi-Argentina, F.; Shestakov, V.

    2002-12-01

    The main issues for the application of beryllium in fusion reactors are analyzed taking into account the latest results since the ICFRM-9 (Colorado, USA, October 1999) and presented at 5th IEA Be Workshop (10-12 October 2001, Moscow Russia). Considerable progress has been made recently in understanding the problems connected with the selection of the beryllium grades for different applications, characterization of the beryllium at relevant operational conditions (irradiation effects, thermal fatigue, etc.), and development of required manufacturing technologies. The key remaining problems related to the application of beryllium as an armour in near-term fusion reactors (e.g. ITER) are discussed. The features of the application of beryllium and beryllides as a neutron multiplier in the breeder blanket for power reactors (e.g. DEMO) in pebble-bed form are described.

  19. Geant4 calculations for space radiation shielding material Al2O3

    Directory of Open Access Journals (Sweden)

    Capali Veli

    2015-01-01

    Full Text Available Aluminium Oxide, Al2O3 is the most widely used material in the engineering applications. It is significant aluminium metal, because of its hardness and as a refractory material owing to its high melting point. This material has several engineering applications in diverse fields such as, ballistic armour systems, wear components, electrical and electronic substrates, automotive parts, components for electric industry and aero-engine. As well, it is used as a dosimeter for radiation protection and therapy applications for its optically stimulated luminescence properties. In this study, stopping powers and penetrating distances have been calculated for the alpha, proton, electron and gamma particles in space radiation shielding material Al2O3 for incident energies 1 keV – 1 GeV using GEANT4 calculation code.

  20. Damage of target edges in brush-like geometry in the course of ELM-like plasma pulses in QSPA Kh-50

    International Nuclear Information System (INIS)

    Castellated edges of macro-brush armour elements of ITER divertor can be a source of molten/solid dust particles which are injected into the plasma. The targets that combined in brush-like geometry have been irradiated under different inclination angles in QSPA Kh-50. The cubic brushes element has typical size of 1 cm. The titanium was used to investigate dynamics of mountains’ formation. The onset of dust particles ejection from the exposed castellated targets has been studied. Formation of resolidified bridges through the gaps of brush-like targets due to the melt motion is studied in dynamics. With following plasma impacts such resolidified bridges became additional source of dust

  1. Damage of target edges in brush-like geometry in the course of ELM-like plasma pulses in QSPA Kh-50

    Energy Technology Data Exchange (ETDEWEB)

    Makhlaj, V.A., E-mail: makhlay@ipp.kharkov.ua [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine); Garkusha, I.E.; Aksenov, N.N. [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine); Bazylev, B. [Karlsruhe Institute of Technology (KIT), IHM, 76344 Karlsruhe (Germany); Byrka, O.V.; Chebotarev, V.V. [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine); Landman, I. [Karlsruhe Institute of Technology (KIT), IHM, 76344 Karlsruhe (Germany); Herashchenko, S.S.; Staltsov, V.V. [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine)

    2015-08-15

    Castellated edges of macro-brush armour elements of ITER divertor can be a source of molten/solid dust particles which are injected into the plasma. The targets that combined in brush-like geometry have been irradiated under different inclination angles in QSPA Kh-50. The cubic brushes element has typical size of 1 cm. The titanium was used to investigate dynamics of mountains’ formation. The onset of dust particles ejection from the exposed castellated targets has been studied. Formation of resolidified bridges through the gaps of brush-like targets due to the melt motion is studied in dynamics. With following plasma impacts such resolidified bridges became additional source of dust.

  2. Melt damage simulation of W-macrobrush and divertor gaps after multiple transient events in ITER

    International Nuclear Information System (INIS)

    Tungsten in the form of macrobrush structure is foreseen as one of two candidate materials for the ITER divertor and dome. In ITER, even for moderate and weak ELMs when a thin shielding layer does not protect the armour surface from the dumped plasma, the main mechanisms of metallic target damage remain surface melting and melt motion erosion, which determines the lifetime of the plasma facing components. The melt erosion of W-macrobrush targets with different geometry of brush surface under the heat loads caused by weak ELMs is numerically investigated using the modified code MEMOS. The optimal angle of brush surface inclination that provides a minimum of surface roughness is estimated for given inclination angles of impacting plasma stream and given parameters of the macrobrush target. For multiple disruptions the damage of the dome gaps and the gaps between divertor cassettes caused by the radiation impact is estimated

  3. Final case for a stainless steel diagnostic first wall on ITER

    International Nuclear Information System (INIS)

    In 2010 the ITER Organization (IO) proposed to eliminate the beryllium armour on the plasma-facing surface of the diagnostic port plugs and instead to use bare stainless steel (SS), simplifying the design and providing significant cost reduction. Transport simulations at the IO confirmed that charge-exchange sputtering of the SS surfaces would not affect burning plasma operation through core impurity contamination, but a second key issue is the potential melt damage/material loss inflicted by the intense photon radiation flashes expected at the thermal quench of disruptions mitigated by massive gas injection. This paper addresses this second issue through a combination of ITER relevant experimental heat load tests and qualitative theoretical arguments of melt layer stability. It demonstrates that SS can be employed as material for the port plug plasma-facing surface and this has now been adopted into the ITER baseline

  4. Final case for a stainless steel diagnostic first wall on ITER

    Energy Technology Data Exchange (ETDEWEB)

    Pitts, R.A., E-mail: richard.pitts@iter.org [ITER Organization, Route de Vinon-sur-Verdon, CS 90 04, 613067 St. Paul Lez Durance Cedex (France); Bazylev, B. [Karlsruhe Institute of Technology, IHM, P.O. Box 3640, 76021 Karlsruhe (Germany); Linke, J. [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, 52425 Juelich (Germany); Landman, I. [Karlsruhe Institute of Technology, IHM, P.O. Box 3640, 76021 Karlsruhe (Germany); Lehnen, M. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 04, 613067 St. Paul Lez Durance Cedex (France); Loesser, D. [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Loewenhoff, Th. [Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, 52425 Juelich (Germany); Merola, M.; Roccella, R. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 04, 613067 St. Paul Lez Durance Cedex (France); Saibene, G. [Fusion for Energy Joint Undertaking, Josep Pla no. 2 – T B3 7/01, Barcelona 08019 (Spain); Smith, M. [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Udintsev, V.S. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 04, 613067 St. Paul Lez Durance Cedex (France)

    2015-08-15

    In 2010 the ITER Organization (IO) proposed to eliminate the beryllium armour on the plasma-facing surface of the diagnostic port plugs and instead to use bare stainless steel (SS), simplifying the design and providing significant cost reduction. Transport simulations at the IO confirmed that charge-exchange sputtering of the SS surfaces would not affect burning plasma operation through core impurity contamination, but a second key issue is the potential melt damage/material loss inflicted by the intense photon radiation flashes expected at the thermal quench of disruptions mitigated by massive gas injection. This paper addresses this second issue through a combination of ITER relevant experimental heat load tests and qualitative theoretical arguments of melt layer stability. It demonstrates that SS can be employed as material for the port plug plasma-facing surface and this has now been adopted into the ITER baseline.

  5. Modelling of radiation impact on ITER Beryllium wall

    International Nuclear Information System (INIS)

    In the ITER H-Mode confinement regime, edge localized instabilities (ELMs) will perturb the discharge. Plasma lost after each ELM moves along magnetic field lines and impacts on divertor armour, causing plasma contamination by back propagating eroded carbon or tungsten. These impurities produce enhanced radiation flux distributed mainly over the beryllium main chamber wall. The simulation of the complicated processes involved are subject of the integrated tokamak code TOKES that is currently under development. This work describes the new TOKES model for radiation transport through confined plasma. Equations for level populations of the multi-fluid plasma species and the propagation of different kinds of radiation (resonance, recombination and bremsstrahlung photons) are implemented. First simulation results without account of resonance lines are presented.

  6. A Comparative Analysis of Sonic Defences in Bombycoidea Caterpillars.

    Science.gov (United States)

    Bura, Veronica L; Kawahara, Akito Y; Yack, Jayne E

    2016-01-01

    Caterpillars have long been used as models for studying animal defence. Their impressive armour, including flamboyant warning colours, poisonous spines, irritating sprays, and mimicry of plant parts, snakes and bird droppings, has been extensively documented. But research has mainly focused on visual and chemical displays. Here we show that some caterpillars also exhibit sonic displays. During simulated attacks, 45% of 38 genera and 33% of 61 species of silk and hawkmoth caterpillars (Bombycoidea) produced sounds. Sonic caterpillars are found in many distantly-related groups of Bombycoidea, and have evolved four distinct sound types- clicks, chirps, whistles and vocalizations. We propose that different sounds convey different messages, with some designed to warn of a chemical defence and others, to startle predators. This research underscores the importance of exploring acoustic communication in juvenile insects, and provides a model system to explore how different signals have evolved to frighten, warn or even trick predators. PMID:27510510

  7. Qualification, commissioning and in situ monitoring of high heat flux plasma facing components

    International Nuclear Information System (INIS)

    Up-to-date development of actively cooled high heat flux (HHF) plasma facing components (PFC) prototypes only allows reduced margins with regards to the ITER thermal requirements. Additionally, perfect quality cannot be ensured along series manufacturing: the presence of flaws which impair the heat transfer capability of the component, in particular at the interface armour/heat sink appears to be statistically unavoidable. In order to ensure a successful series production, a qualification methodology of actively cooled high heat flux plasma facing components is proposed. Secondly, advanced non-destructive techniques developed for HHF PFC commissioning are detailed with definition of acceptance criteria. Finally, innovative diagnostics for in situ monitoring during plasma operations or tokamak shutdowns are investigated in order to prevent immediate damage (safety monitoring); or evaluate component degradation (health monitoring). This work takes into account the relevance to Tore Supra, and is applied to W7X and ITER Divertor HHF PFC

  8. Wave Run-Up on a Rubble Mound Breakwater

    DEFF Research Database (Denmark)

    Rouck, J. De; Troch, P.; Walle, B. Van de;

    2001-01-01

    found by laboratory testing and reported in literature. The design of the crest height of a breakwater is mainly based on wave run-up values obtained by small scale model tests. Prototype measurements are seen as the big challenge to be addressed to verify small scale model test results. Therefore, a......-o dimensional models (1:30) and on one thr-e dimensional scale model (1:40). For a better determination of wave run-up on the scale models, a novel step gauge is developed. Still, differences between results of prototype measurement and small scale model test results and between the various laboratory results...... rubble mound breakwater protecting the outer harbour of Zeebrugge (Belgium) and armoured with 25 ton grooved cubes is fully instrumented to measure sea state, wave run-up and wave overtopping. Wave run-up is measured by two different measuring devices. Extensive laboratory testing is carried out on two t...

  9. Scale Effects Related to Small Physical Modelling of Overtopping of Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke

    2009-01-01

    By comparison of overtopping discharges recorded in prototype and small scale physical models it was demonstrated in the EU-CLASH project that small scale tests significantly underestimate smaller discharges. Deviations in overtopping are due to model and scale effects. These effects are discussed...... in the paper and it is explained why it is impossible quantitatively to identify model and scale effects by comparison of the performance of prototype and small scale models. For such identification are needed special dedicated tests. The paper presents such a test which identify the scale effect in...... the rubble armour on the upper part of the slope. This effect is believed to be the main reason for the found deviations between overtopping in prototype and small scale tests....

  10. Spray nozzle for fire control

    Science.gov (United States)

    Papavergos, Panayiotis G.

    1990-09-01

    The design of a spray nozzle for fire control is described. It produces a spray of gas and liquid having an oval transverse cross section and it comprises a mixing chamber with an oval transverse cross section adapted to induce a toroidal mixing pattern in pressurized gas and liquid introduced to the mixing chamber through a plurality of inlets. In a preferred embodiment the mixing chamber is toroidal. The spray nozzle produces an oval spray pattern for more efficient wetting of narrow passages and is suitable for fire control systems in vehicles or other confined spaces. Vehicles to which this invention may be applied include trains, armoured vehicles, ships, hovercraft, submarines, oil rigs, and most preferably, aircraft.

  11. Integrating developmental biology and the fossil record of reptiles.

    Science.gov (United States)

    Skawiński, Tomasz; Tałanda, Mateusz

    2014-01-01

    Numerous new discoveries and new research techniques have influenced our understanding of reptile development from a palaeontological perspective. They suggest for example that transition from mineralized to leathery eggshells and from oviparity to viviparity appeared much more often in the evolution of reptiles than was previously thought. Most marine reptiles evolved from viviparous terrestrial ancestors and had probably genetic sex determination. Fossil forms often display developmental traits absent or rare among modern ones such as polydactyly, hyperphalangy, the presence of ribcage armour, reduction of head ornamentation during ontogeny, extreme modifications of vertebral count or a wide range of feather-like structures. Thus, they provide an empirical background for many morphogenetic considerations. PMID:26154335

  12. Adaptación e implementación de un programa de intervención en la escuela a través de la educación física: el Programa de responsabilidad personal y social

    Directory of Open Access Journals (Sweden)

    Diana Marín Suelves

    2014-12-01

    Full Text Available En las últimas décadas ha aumentado en padres y educadores la preocupación por el fracaso y la violencia escolar (Fraser-Thomas, Côté, & Deakin, 2005; Hawkins, Catalano, Kosterman, Abbot, & Hill, 1999. Por ello, han surgido programas para mejorar las competencias personales y sociales de sus participantes (Brustad & Parker, 2005; Gould & Carson, 2008 mediante la actividad física y el deporte (Petitpas, Cornelius, Van Raalte, & Jones, 2005; Sandford, Armour, & Warmington, 2006; Wright & Burton, 2008. Muchos de estos programas se desarrollan en las clases de educación física por ser este un contexto idóneo para el desarrollo positivo (Gould & Carson, 2008, por las horas de permanencia en la escuela (Ward, Saunders, & Pate, 2007 y por las posibilidades para el aprendizaje de valores útiles en la escuela y en la vida (Sandford et al., 2006.

  13. Ballistic evaluationof LOVA propellant in high calibre gun

    Directory of Open Access Journals (Sweden)

    A.G.S. Pillai

    2001-04-01

    Full Text Available 'This paper presents the data obrained on dynamic firing of a cellulose acetate binder-based low vulnerability ammunition (LOV A propellant using 120 mm fin-stabilised armour piercing discarding sabot (FSAPDS kinetic energyammunition. An optimised propellant composition formulated ~sing fine RDX as an energetic ingredient and a mixture of cellulose acetate and nitrocellulose as binder was qualified fit for firing in a high calibre gun by its successful static evaluation for absolute ballistics using high pressure closed vessel technique. Dynamic firing of the propellant processed in heptatubular geometry was undertaken to assess the propellant charge mass. This propellant achieved higher muzzle velocity as compared to the standard NQ/M119 triple-base propellant while meeting the non-vulnerability characteristics convincingly.

  14. 100 Years of British military neurosurgery: on the shoulders of giants.

    Science.gov (United States)

    Roberts, S A G

    2015-01-01

    Death from head injuries has been a feature of conflicts throughout the world for centuries. The burden of mortality has been variously affected by the evolution in weaponry from war-hammers to explosive ordnance, the influence of armour on survivability and the changing likelihood of infection as a complicating factor. Surgery evolved from haphazard trephination to valiant, yet disjointed, neurosurgery by a variety of great historical surgeons until the Crimean War of 1853-1856. However, it was events initiated by the Great War of 1914-1918 that not only marked the development of modern neurosurgical techniques, but our approach to military surgery as a whole. Here the author describes how 100 years of conflict and the input and intertwining relationships between the 20th century's great neurosurgeons established neurosurgery in the United Kingdom and beyond. PMID:26292388

  15. Smart Munitions (Review Paper

    Directory of Open Access Journals (Sweden)

    C. P. Mahajan

    2010-03-01

    Full Text Available In modern land warfare, munitions are considered as highly effective means of the defence against an invading force, especially armoured fighting vehicles. In recent decades, new technologies have transformed the dumb land munitions, into sophisticated smart munitions that can be used for offensive purposes. The evolution in the munitions technology was marked by the introduction of sensored smart munitions. Armament Research and Development Establishment (ARDE has achieved a technological breakthrough by developing world class sensor-based influence land munitions Adrushy MK-I and subsequently Adrushy MK-II. Successful development of these smart influence munitions has made India proud and at par with the world market.Defence Science Journal, 2010, 60(2, pp.159-163, DOI:http://dx.doi.org/10.14429/dsj.60.334

  16. Status of the ITER full-tungsten divertor shaping and heat load distribution analysis

    International Nuclear Information System (INIS)

    In September 2011, the ITER Organization (IO) proposed to begin operation with a full-tungsten (W) armoured divertor, with the objective of taking a decision on the final target material (carbon fibre composite or W) by the end of 2013. This period of 2 years would enable the development of a full-W divertor design compatible with nuclear operations, the investigation of further several physics R and D aspects associated with the use of W targets and the completion of technology qualification. Beginning with a brief overview of the reference heat load specifications which have been defined for the full-W engineering activity, this paper will report on the current status of the ITER divertor shaping and will summarize the results of related three-dimensional heat load distribution analysis performed as part of the design validation. (paper)

  17. Depleted Uranium—Experience of the United Nations Environmental Programme Missions

    Science.gov (United States)

    Åkerblom, Gustav

    2008-08-01

    Depleted Uranium (DU) is used in ammunition designed for armour-piercing. DU was used in the Gulf war 1991, wars in Bosnia 1994-1995, Kosovo 1999 and Iraq 2003. The United Nations Environmental Programme (UNEP) Post-Conflict Branch investigated sites where DU was used and evaluated health and environmental risks during missions to Kosovo, Serbia and Bosnia. During a mission to Lebanon in 2006, UNEP also sampled areas where DU was supposed to have been used but did not find any DU. Due to the grave risks to the lives of UN personnel, no UNEP mission was carried out in Iraq. UNEP has provided training for personnel engaged in decontamination of DU in Bosnia and Iraq.

  18. SOUTH AFRICA'S MILITARY ON THE MOVE

    Directory of Open Access Journals (Sweden)

    J.P. McWilliams

    2012-02-01

    Full Text Available If one looks at the South African Defence Force (SADF, it becomes apparent that it is the strongest defence force in Africa based on trained manpower, organisation, weapons systems, mobilisation capacity and defence budget. The Republic of South Africa has the capability to procure and manufacture the overwhelming majority of its weapons and armaments through its existing parastatal, Armaments Corporation of South Africa Ltd. (Armcscor. According to The Military Balance, 1986-87, published by the International Institute for Strategic Studies, (IISS, South Africa has 250 Centurian/Olifant tanks, 1 600 Eland armoured cars, 1 500 Ratel Infantry combat vehicles, 372 combat aircraft, 16 armed helicopters and 144 other helicopters. The SADF can mobilize over 400 000 personnel. Defence expenditures for 1985/6 were 2,27 billion dollars. The defence budget for 1986/7 indicates allocations of 2,012 billion dollars.

  19. The characterization of artefacts of cultural heritage significance using physical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Creagh, D.C. [Cultural Heritage Research Centre, Division of Science and Design, University of Canberra, Canberra ACT 2601 (Australia)]. E-mail: dcreagh@bigpond.net.eu

    2005-12-15

    All societies attempt to preserve their cultural heritage because it is this that gives them their identity. How artefacts are identified as being of significance to society, and how to preserve these for posterity, depend on the sophistication of those societies, their wealth, and the determination of members of the societies to preserve their past. If conservation or restoration measures are being undertaken complex analytical experiments must be undertaken beforehand to ensure that the work is being undertaken in an appropriate manner. These investigations may employ electromagnetic (IR, VIS, UV, X-ray, {gamma}-ray) or particulate (electron, proton, neutron, and ion beams) radiation. The use of many of these techniques is described in this paper in experiments on Australian Aboriginal bark paintings, a suit of armour belonging to a famous Australian outlaw, and the degradation of colour motion picture film.

  20. Spark plasma sintering of pure and doped tungsten as plasma facing material

    International Nuclear Information System (INIS)

    In the current water cooled divertor concept, tungsten is an armour material and CuCrZr is a structural material. In this work, a fabrication route via a powder metallurgy process such as spark plasma sintering is proposed to fully control the microstructure of W and W composites. The effect of chemical composition (additives) and the powder grain size was investigated. To reduce the sintering temperature, W powders doped with a nano-oxide dispersion of Y2O3 are used. Consequently, the sintering temperature for W-oxide dispersed strengthened (1800 °C) is lower than for pure W powder. Edge localized mode tests were performed on pure W and compared to other preparation techniques and showed promising results. (paper)

  1. Strain Rate Effect on the Tensile Behavior of Fibers and Its Application to Ballistic Perforation of Multi-layered Fabrics

    Institute of Scientific and Technical Information of China (English)

    GU Bo-hong; PAN Xiong-qi

    2002-01-01

    Rate-dependent property of material is very important in analysis of ballistic impact. The tensile property of Twaron(R) filaments at strain rate range from 0.01/s to1 000/s was obtained by MTS materials testing and split Hopkinson tension bar. Rate sensitivity of Twaron(R) filaments is discussed. Application of high strain rate property to ballistic perforation of multi- layered fabrics conforms to the actual situation than that of quasi-static property. The revised analytical model can be used to calculate the process of ballistic penetration and perforation on soft armour, such as fabric target plate,at intuitive approach and simple algorithm with a little computer process time. Predictions of the residual velocities and energy absorbed by the multi- layered fabric show good agreement with experimental data.

  2. On the drop-weight testing of alumina/aluminum laminated composites

    Indian Academy of Sciences (India)

    Mustafa Übeylı; R Orhan Yildirim; Bılgehan Ögel

    2005-10-01

    Laminated composites with ceramic front layers and metallic or composite backing layers have gained attractiveness as lightweight armours, as they exhibit the same ballistic performance with lower areal densities as compared to steels. Drop-weight testing (DWT) has potential for evaluating the low velocity impact behaviour of materials. This testing gives significant ideas and information about failure mechanisms and behaviour of materials under low velocity impact. In this study, DWT of alumina/aluminum laminated composites was done in order to investigate the effects of lamination type, density with respect to area and mechanical property of backing material on the low velocity ballistic performance of these composites. The experimental results showed that the laminated composite with ceramic front layer and aged-aluminum alloy as backing layer was the most effective among different investigated specimens against low velocity impact loads.

  3. PLC based Smart Street Lighting Control

    Directory of Open Access Journals (Sweden)

    D.V.Pushpa Latha

    2013-12-01

    Full Text Available Conventional street lighting systems in most of the areas are Online at regular intervals of time irrespective of the seasonal variations. The street lights are simply switched on at afternoon and turned off in the morning. The consequence is that a large amount of Power is wasted meaninglessly. As energy consumption is an issue of increasing interest, possible energy savings in public street lighting systems are recently discussed from different viewpoints. The purpose of this work is to describe the Smart Street Lighting system, an approach to accomplish the demand for flexible public lighting systems using a Programmable Logic controller (PLC. The main difference from other computers is that PLCs are armoured for severe conditions such as dust, moisture, heat, cold etc., and have the facility for extensive input/output (I/O arrangements. In the proposed paper, street lights are controlled using millennium 3 PLC taking the seasonal variations into consideration.

  4. Performance Improvement of Cooling Systemin T72 Bridge Layer Tank

    Directory of Open Access Journals (Sweden)

    N. Venkateswaran

    2008-01-01

    Full Text Available Modern armoured fighting vehicles (AFVs are provided with compact and efficient coolingsystems. Any increase in volume warrants the protection which, in turn, increases the weightand size of the vehicle. In a combat vehicle, space is at premium. The AFVs (battle tanks usedby the Indian Army were found to be overheating when operated in deserts at very high-ambienttemperatures of 323K (50 oC. This imposes severe restrictions in operating the tanks for prolongedtime in deserts. The various subsystems of the cooling pack were investigated scientifically andan optimised solution was arrived at, implemented and proved successful in the subsequentdesert trials. This paper deals with the details of investigations, modifications, and the resultsof studies on bridge layer tank (BLT–T72.Defence Science Journal, 2008, 58(1, pp.77-85, DOI:http://dx.doi.org/10.14429/dsj.58.1626

  5. Radiometric report for a blast furnace tracing with radioactive isotopes

    International Nuclear Information System (INIS)

    One of the methods to monitor refractory wall of blast furnace is its tracing with radioactive isotopes. The tracer isotope can be detected by two ways: the external dosimetric measurement at the armour of the blast furnace and/or the radiometric measurement of the iron sample charge by charge. Any change in radiometric situation of tracer radioisotope is recorded in a radiometric report. This paper presents an original concept of radiometric report based upon PARADOX and CORELDRAW soft kits. Their advantage are: quick and easy changes, easy recording of current radioactivity of tracer isotope, short history of changes, visual mapping of the tracer isotope and others. In this way we monitored 6 blast furnaces and more than 180 radioactive sources

  6. Analytical and Numerical Modeling for Flexible Pipes

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; CHEN Geng

    2011-01-01

    The unbonded flexible pipe of eight layers,in which all the layers except the carcass layer are assumed to have isotropic properties,has been analyzed.Specifically,the carcass layer shows the orthotropic characteristics.The effective elastic moduli of the carcass layer have been developed in terms of the influence of deformation to stiffness.With consideration of the effective elastic moduli,the structure can be properly analyzed.Also the relative movements of tendons and relative displacements of wires in helical armour layer have been investigated.A three-dimensional nonlinear finite element model has been presented to predict the response of flexible pipes under axial force and torque.Further,the friction and contact of interlayer have been considered.Comparison between the finite element model and experimental results obtained in literature has been given and discussed,which might provide practical and technical support for the application of unbonded flexible pipes.

  7. Static equilibrium analysis for pipeline protection design in Iran LNG port

    Energy Technology Data Exchange (ETDEWEB)

    Abdollahi, A.S.; Vakili, R. [Iran Univ. of Science and Technology, Tehran, (Iran, Islamic Republic of); Alielahi, H. [Islamic Azad Univ., Zanjan (Iran, Islamic Republic of)

    2010-07-01

    This paper discussed the protection design for an intake seawater pipeline that will be built for a liquefied natural gas (LNG) project. The limit equilibrium approach was used to estimate the geometry of the protection layer with respect to the holding capacity of the drag anchors in cohesionless soil, incorporating a more realistic 3-dimensional failure pattern in the soil as well as the force acting on the back of the fluke. The study addressed all technical and executive points related to the pipeline construction, including anchor type, ship load, geotechnical properties of the protected zone and the underlying seabed, and the procedure to calculate the geometry of the protection layer. The protection layer must account for the complexity of interactions among anchor, anchor chain, sea bed, and rock armour. This analytical method provided logical results more quickly and at a lower cost than model testing. 14 refs., 3 tabs., 9 figs.

  8. Development and tests of molybdenum armored copper components for MITICA ion source

    Energy Technology Data Exchange (ETDEWEB)

    Pavei, Mauro, E-mail: mauro.pavei@igi.cnr.it; Marcuzzi, Diego; Rizzolo, Andrea; Valente, Matteo [Consorzio RFX, Corso Stati Uniti, 4, I-35127 Padova (Italy); Böswirth, Bernd; Greuner, Henri [Max-Planck-Institut für Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

    2016-02-15

    In order to prevent detrimental material erosion of components impinged by back-streaming positive D or H ions in the megavolt ITER injector and concept advancement beam source, a solution based on explosion bonding technique has been identified for producing a 1 mm thick molybdenum armour layer on copper substrate, compatible with ITER requirements. Prototypes have been recently manufactured and tested in the high heat flux test facility Garching Large Divertor Sample Test Facility (GLADIS) to check the capability of the molybdenum-copper interface to withstand several thermal shock cycles at high power density. This paper presents both the numerical fluid-dynamic analyses of the prototypes simulating the test conditions in GLADIS as well as the experimental results.

  9. 5. IEA International workshop on beryllium technology for fusion. Book of abstracts

    International Nuclear Information System (INIS)

    The collection includes the abstracts of reports presented to the 5-th IEA international workshop on beryllium technology for fusion. The themes of reports are as follows: status of beryllium technology for fusion in Russia; manufacturing and testing of Be armoured first wall mock-up for ITER; development of the process of diffusion welding of metals stainless steel-copper-beryllium into a single composite; some features of beryllium-laser beam interaction; the effect of irradiation dose on tritium and helium release from neutron irradiated beryllium; thermal properties of neutron irradiated Be12Ti. The results of investigating the mechanical properties variation and swelling of beryllium under high temperature neutron irradiation are presented

  10. Non-Contact Measurement of Thermal Diffusivity in Ion-Implanted Nuclear Materials.

    Science.gov (United States)

    Hofmann, F; Mason, D R; Eliason, J K; Maznev, A A; Nelson, K A; Dudarev, S L

    2015-01-01

    Knowledge of mechanical and physical property evolution due to irradiation damage is essential for the development of future fission and fusion reactors. Ion-irradiation provides an excellent proxy for studying irradiation damage, allowing high damage doses without sample activation. Limited ion-penetration-depth means that only few-micron-thick damaged layers are produced. Substantial effort has been devoted to probing the mechanical properties of these thin implanted layers. Yet, whilst key to reactor design, their thermal transport properties remain largely unexplored due to a lack of suitable measurement techniques. Here we demonstrate non-contact thermal diffusivity measurements in ion-implanted tungsten for nuclear fusion armour. Alloying with transmutation elements and the interaction of retained gas with implantation-induced defects both lead to dramatic reductions in thermal diffusivity. These changes are well captured by our modelling approaches. Our observations have important implications for the design of future fusion power plants. PMID:26527099

  11. Microcontroller based ground weapon control system(Short Communication

    Directory of Open Access Journals (Sweden)

    M. Sankar Kishore

    2001-10-01

    Full Text Available Armoured vehicles and tanks generally consist of high resolution optical (both infrared and visible and display systems for recognition and identification of the targets. Different weapons/articles to engage the targets may be present. A fire control system (FCS controls all the above systems, monitors the status of the articles present and passes the information to the display system. Depending upon the health and availability of the articles, the FCS selects and fires the articles. Design and development of ground control unit which is the heart of the FCS, both in hardware and software, has been emphasised. The system has been developed using microcontroller and software developed in ASM 51 language. The system also has a facility to test all the systems and articles as initial power on condition. From the safety point of view, software and hardware interlocks have been provided in the critical operations, like firing sequence. "

  12. Investigation of slot discharge on a 239 MVA hydro generator stator winding

    Energy Technology Data Exchange (ETDEWEB)

    Li, S.; Hong, W. [BC Hydro and Power Authority, Vancouver, BC (Canada)

    2009-07-01

    This paper discussed a slot discharge investigation conducted on a 239 MVA generator stator winding. The generator in which the winding was located had experienced core split distortion, stator winding phase-to-phase failures, winding failures during Hipot testing, and high partial discharge (PD) activity. The results of on-line PD testing data were evaluated. The stator winding was subjected to visual inspections, bar dissections, and failure mechanism analyses. Eleven winding bars were removed from the stator slots in order to assess groundwall insulation conditions and identify the cause of the slot discharge activity. It was determined that the root cause of the slot discharge was a loose, non-uniform bar in the slot. The vibrating bar caused the semi-conductive coating to wear out and degraded the armour tape. Results of the study demonstrated the importance of on-line PD monitoring for detecting slot PD activity. 4 refs., 3 tabs., 11 figs.

  13. Power Tillers for Demining: Blast Test

    Directory of Open Access Journals (Sweden)

    Emanuela Elisa Cepolina

    2008-11-01

    Full Text Available Power tillers are very simple and versatile machines with large scale diffusion in developing countries, where they are commonly used both for agriculture and for transportation purposes. A new integrated participatory approach that makes use of and improves local end-users knowledge has been used to design a new robotic system for humanitarian demining applications in Sri Lanka, using power tiller as core module. A demining machine composed by a tractor unit, a ground processing tool and a vegetation cutting tool is here presented together with results obtained from the first blast test on the preliminary version of tractor unit armouring. Different breakable connections between wheels and axle have been designed to cause physical detachment and interrupt the transmission of the shock wave released by the explosion of a mine under one wheel. Effects of explosions on different types of wheels and on the chassis have been recorded and commented.

  14. The gravel sand transition in a disturbed catchment

    Science.gov (United States)

    Knighton, A. David

    1999-03-01

    More than 40 million cubic metres of mining waste were supplied to the Ringarooma River between 1875 and 1984, leading to successive phases of aggradation and degradation. The natural bed material is gravel but, given the volume of introduced load and the fact that much of the input was less than 5 mm in diameter, the size composition of the bed changed from gravel to sand during the phase of downstream progressive aggradation. A very sharp gravel-sand transition developed in which median grain size decreased from over 30 mm to under 3 mm in less than 500 m. With upstream supplies of mining debris becoming depleted first, degradation followed the same downstream progressive pattern as aggradation, causing the transition to migrate downstream. By 1984, the river could be regarded as a series of zones, each characterized by a particular bed condition: a natural cobble-gravel bed, unaffected by mining inputs (0-32 km); pre-disturbance bed re-exposed by degradation over 35-40 years (32-53 km); sandy substrate with a gravel armour produced by differential transport during degradation (53-65 km); sand dominated but with developing surface patches of coarser material (65-75 km); sandy bed reflecting the size composition of the original mining input (75-118 km). Although the gravel-sand transition itself is sharp, the transitional zone is lengthy (53-75 km). As degradation continues, the gravel-sand transition is expected to progress downstream but it has remained in a stable position for 12 years. Indeed, two major floods during the period released large quantities of sand from the sub-armour layer and newly-formed banks of mine tailings, causing fining both above and below the transition. Surface grain size is an adjustable component in the transitional zone as the river strives to recover from a major anthropogenic disturbance.

  15. Tritrophic effects on survival and development in a Coccidophagous coccinellid.

    Science.gov (United States)

    Boothe, R A; Ponsonby, D J; Preziosi, R F; Copland, M J W

    2008-01-01

    Chilocorus nigritus is currently considered one of the most successful biological control agents of armoured scale insects. However, establishment of this beetle in crop pest situations has not always been successful and there are still gaps in our knowledge of its ecology and behaviour. The research involved an examination of tritrophic effects on the survival and development of this common diaspid predator. The effect of a forced change in host plant on the developmental time of the juvenile stages was also examined. The prey and host plants used were the armoured scales Aspidiotus nerii Bouché Homoptera: Diaspididae and Abgrallaspis cyanophylli (Signoret) Homoptera: Diaspididae, on potatoes (Solanum tuberosum L.) and Butternut squashes (Cucurbita moschata Duchesne ex Lamarck). C. nigritus eggs were incubated on four treatments of scales on potatoes or squashes for ten days, half the second instar larvae were then switched to the same scales on the other host plant. Daily observations were made during development to adult emergence. C. nigritus larvae survived and completed development on two species of diaspid scales and the two host plants examined with varying levels of success. Larvae were able to switch from feeding on A. nerii on potatoes to A. nerii on squashes or A. cyanophylli on potatoes to A. cyanophylli on squashes and vice versa with little or no deleterious effects when compared to those beetles reared on one prey and host plant throughout. There were significant differences in survival of larvae reared to the adult stage on both A. nerii and A. cyanophylli on potatoes when compared to larvae reared on these scales on squashes. Squash appears to be a less desirable and potato a more favourable host plant for survival and development. The results have implications for rearing programmes, and the release and establishment of C. nigritus, in fields and glasshouses where scale pests may be present on a variety of host plants, or may be on host plants

  16. Bullet dents – “Proof marks” or battle damage

    Directory of Open Access Journals (Sweden)

    Williams, Alan

    2006-12-01

    Full Text Available

    It is well known that the breastplates of many armours from the later 16th century and the 17th century bear the hemispherical dents generally known as proof marks. It has been taken as axiomatic that these marks were made in order to demonstrate the armours’ effectiveness against firearms. If however some of these dents are compared with dents which are the result of battle damage, it appears that they were made by energy levels of a different order of magnitude, and offer little guarantee as to the “proof” of the armour.



    Como es bien sabido, muchos petos de armaduras de finales del siglo XVI y del XVII tienen abolladuras semiesféricas conocidas como pruebas de arcabuz. Se ha considerado axiomático que estas abolladuras fueron hechas para demostrar la efectividad de las armaduras frente a las armas de fuego. Sin embargo, si se comparan con otras debidas a daños en combate, parece que fueron producidas por energías de diferente orden o magnitud, al tiempo que ofrecen pocas garantías como “pruebas” de las armaduras.

  17. Material Surface Damage under High Pulse Loads Typical for ELM Bursts and Disruptions in ITER

    International Nuclear Information System (INIS)

    The divertor armour material for the tokamak ITER will probably be carbon manufactured as fibre composites (CFC) and tungsten as either brush-like structures or thin plates. Disruptive pulse loads where the heat deposition Q may reach 102 MJ/m2 on a time scale τ of 3 ms, or operation in the ELMy H-mode at repetitive loads with Q ∼ 3MJ/m2 and τ∼0.3 ms; deteriorate armour performance. This work surveys recent numerical and experimental investigations of erosion mechanisms at these off-normal regimes carried out at FZK, TRINITI, and IPP-Kharkov. The modelling uses the anisotropic thermomechanics code PEGASUS-3D for the simulation of CFC brittle destruction, the surface melt motion code MEMOS-1.5D for tungsten targets, and the radiation-magnetohydrodynamics code FOREV-2D for calculating the plasma impact and simulating the heat loads for the ITER regime. Experiments aimed at validating these codes are being carried out at the plasma gun facilities MK-200UG, QSPA-T, and QSPA-Kh50 which produce powerful streams of hydrogen plasma with Q=10-30MJ/m2 and τ = 0.03-0.5 ms. Essential results are, for CFC targets, the experiments at high heat loads and the development of a local overheating model incorporated in PEGASUS-3D, and for the tungsten targets the analysis of evaporation- and melt motion erosion on the base of MEMOS-1.5D calculations for repetitive ELMs

  18. Fragmentation and lethality

    Directory of Open Access Journals (Sweden)

    V. R. Thiruvenkatachar

    1958-04-01

    Full Text Available "The lethality of a H.E. shell or bomb depends on its ability to produce high velocity fragments and blast. The relative importance of these two damaging agents depends on the nature of the targets it is proposed to destroy. Small, high-velocity fragments are effective for the attack of personnel in the open, but aircraft targets require larger fragments. The blast effect from shell-burst inside aircraft wings does considerable damage, but blast is of relatively little importance against heavily armoured targets such as tanks. Fragment effect ceases to be of primary importance here and if the HE shell is to be lethal to such targets it must carry a very large charge of explosive, which will either ""scab"" the armour or do extensive structural damage by blast and shock. For assessing the effectiveness of a fragmenting shell or bomb against a given type of target, we have to take into account different characteristics of ammunition and target. The solution of the problem of lethality of ammunition will involve a determination of fragmentation in regard to total number of a design with a specific level of lethality in a given situation, it will be necessary to predict the performance for given design data, a process which demands a theoretical treatment if possible, or at least a sufficient quantity of experimental data which can yield reliable empirical formulae. In this paper an account is given of the various theoretical and empirical aspects and a discussion of these with reference to certain special cases. "

  19. Regional variation of urinary excretion of Uranium in non-exposed subjects

    International Nuclear Information System (INIS)

    Among the naturally occurring radioactive elements, uranium is present quite ubiquitously in the environment. Due to the solubility of many of its compounds, uranium enters the human body mainly by ingestion with food and drink, especially with tap water and mineral water and to a lesser extent by inhalation of breathable uranium-containing dust particles or aerosols. The average daily intake of uranium in different countries has been investigated in several studies. Values were found ranging between 11 and 18 mBq 238U per day, which are equivalent to 0.9 to 1.5 μg of uranium. Uranium is absorbed from the intestine or the lungs into the systemic part of the body and is rapidly deposited in the tissues, predominately in kidney and bone, or excreted in the urine. Only about 2% of the ingested amount actually enters from the gastrointestinal tract into the systemic circulation, while the remainder passes through the gastrointestinal tract without being absorbed and is excreted with the feces within a few days. Besides its use in nuclear industry, uranium is also associated with certain military applications, such as nuclear weapons, armours, and armour-piercing projectiles. As uranium is known both for its chemical and radio-toxicity, the incorporation of uranium may result in significant internal radiation exposure. In order to assess and control the occupational contribution of internal exposure to uranium in workers, it is important to have reliable information on the biokinetic behaviour of uranium in humans, i.e. its natural intake and body content has to be taken into consideration. Monitoring of occupational incorporation of 238U should preferably be carried out by analysis of its urinary excretion since the quantity lost per day via urine is related to the systemic body content. But for a reliable estimation of the occupational uptake of workers, baseline data of daily urinary excretion in subjects non-exposed occupationally is required

  20. Movable scour protection. CFD calculation of flow and scour around foundation

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.

    2002-07-01

    In the design of scour protections a basic parameter is the variation of the bed shear stress around the structure and the potential of the flow for using the stones of the scour protection. This report investigates whether it is: 1. Possible to calculate the correct bed shear stress for various wave and current situations at the base of the foundations, 2. Possible to calculate the scour depths with and without scour protection or in the case of movable scour protection. A number of test runs were made with the Elypsos computer code with the added morphological module (=sediment transport module). It turned out that it is possible to make such calculations but they are extremely time consuming on even a large computer for a simple structure like the circular foundation. It turns out that the computations overpredict the scour depth somewhat. Therefore a more practical approach was made. The morphological model was taken out. Instead the distribution of bottom shear stress distribution around the base of the structure was calculated. This is the important parameter for designing the armour layer of the scour protection. The Shields criterion was used for predicting stable stones and a suitable high value of the shear stress is used. The high bottom shear stress appears for a horizontal bottom. If the sea bottom is allowed to deepen in the areas with maximum shear stress amplification the horseshoe eddy is weakened. This again reduces the shear stress amplification. The computer program was used to perform such calculations and it turned out to be a powerful tool for this. The shear stress amplification can be reduced with a factor 2. Interactively, it is thus possible to calculate the form of a scour hole by trial and error. The scour protection surface shape with the smallest amplification of the shear stress and with the shear stress below the critical Shields Parameter is the optimum scour protection. The program can be used interactively to calculate the extent

  1. Design of the ITER Plasma-Facing Components

    Energy Technology Data Exchange (ETDEWEB)

    Merola, M.

    2009-07-01

    The ITER plasma-facing components cover an area of about 850 m{sup 2} and consist of the Divertor, the Blanket and the Test Blanket Modules (TBMs) with their corresponding frames. The Divertor is located at the bottom of the plasma chamber and is aimed at exhausting the major part of the plasma thermal power (including alpha power) and at minimizing the helium and impurity content in the plasma. It consists of 54 cassette assemblies. Each assembly has 3 plasma-facing components (PFCs), namely the inner and outer target and the dome, which are mounted onto a steel support structure, the cassette body. The targets directly intercept the magnetic field lines and are designed to withstand heat fluxes as high as 20 MW/m{sup 2}. CFC is the reference design solution for the armour of the lower part of the targets. However, the resultant high erosion rate could potentially limit machine operation in the DT phase (due to co-deposition with T). Therefore, prior to the DT phase, the divertor PFCs will be replaced with a new set entirely covered with W armour. The Divertor is a RH Class 1 component, which is planned to be replaced 3 times during the 20 years of the ITER operation. The construction phase of the ITER Divertor is being launched. The Blanket covers the largest fraction of the plasma-facing surface. Each of the 440 Blanket modules consists of a first wall (FW) panel, which is mechanically attached onto a Shield Module (SM). The design heat flux is set up to 1 or 5 MW/m{sup 2}. The FW panels are covered by Be tiles, which are joined onto a copper alloy (CuCrZr) heat sink, which is in turn intimately joined onto a 316L(N) stainless steel part. The SM is a block of 316L(N)-IG steel, where an array of cooling channels are obtained by machining and welding. The TBMs are mock-ups of DEMO breeding blankets. There are three ITER equatorial ports devoted to TBM testing, each of them allocating two TBMs, inserted in a thick steel frame. The frame is a water-cooled 316L

  2. Actively cooled plasma facing components qualification, commissioning and health monitoring

    International Nuclear Information System (INIS)

    In modern steady state magnetic fusion devices, actively cooled plasma facing components (PFC) have to handle heat fluxes in the range of 10-20 MW/m2. This generates a number of engineering constraints: the armour materials must be refractory and compatible with plasma wall interaction requirements (low sputtering and/or low atomic number); the heat sink must offer high thermal conductivity, high mechanical resistance and sufficient ductility; the component cooling system -which is generally based on the circulation of pressurized water in the PFC's heat sink - must offer high thermal heat transfer efficiency. Furthermore, the assembling of the refractory armour material onto the metallic heat sink causes generic difficulties strongly depending on thermo-mechanical properties of materials and design requirements. Life time of the PFC during plasma operation are linked to their manufacturing quality, in particular they are reduced by the possible presence of flaw assembling. The fabrication of PFC in an industrial frame including their qualification and their commissioning - which consists in checking the manufacturing quality during and at the end of manufacture - is a real challenge. From experience gained at Tore Supra on carbon fibre composite flat tiles technology components, it was assessed that a set of qualifications activities must be operated during R(and)D and manufacturing phases. Dedicated Non Destructive Technique (NDT) based on advanced active infrared thermography was developed for this purpose, afterwards, correlations between NDT, high heat flux testing and thermomechanical modelling were performed to analyse damage detection and propagation, and define an acceptance criteria valuable for industrial application. Health monitoring using lock-in technique was also recently operated in-situ of the Tore Supra tokamak for detection of possible defect propagation during operations, presence of acoustic precursor for critical heat flux detection induced

  3. Nuclear radiation monitoring instruments for personnel in nuclear disaster for defence needs

    International Nuclear Information System (INIS)

    Ever since the tragedy of nuclear device exploding over Japan by USA in 1945 awareness exists amongst the armed forces personnel all over the world that a requirement of implementing radiological protection is imminent. Towards this adoption of radiological safety programme is a criterion. In a nuclear war disaster scenario, one encounters initial nuclear radiation (gamma and neutron radiations), gamma radiations from fallout, heat and blast. At certain distances Tanks/ armoured vehicles will survive and 4 R/s radiation level sensing to actuate relays for closing the ports of vehicles is essential, leading to reduction in inhalation, ingestion of fallout radioactivity and reduction in radiation dose received by occupants of the vehicle. Towards this sturdy radiation monitors to indicate gamma dose rate of the order of 1000 R/h, gamma and neutron dosimeters of the order of 1000 cGy with reading instruments are to be developed. These must work in harsh environment and sustain JSS 55555 conditions of army. Defence Laboratory, Jodhpur over past one decade has been involved in developing personnel, area and field monitoring instruments like dosimeters, survey meters, which are useful, acceptable to army personnel, armoured and personnel carrier vehicles, field structures/shelters. Technology transfer after satisfaction of armed forces, product ionisation and supply, maintenance, training has been the endeavor of the DRDO. Herein it is proposed to highlight the techno electronics nuclear radiation monitoring sensors and associated electronics systems developed first time in the country and productionised in bulk for Services for implementing personnel protection. The sensors developed and described are - Radiophotoluminescent Glass (RPLG) for gamma radiation dosimetry , neutron sensitive PIN diode for fast neutron dosimetry, gamma radiation sensitive PIN diode, superheated liquid neutron and gamma sensors. The dosimeter, dose rate meter and field/area instruments are

  4. Simulations of Material Damage and High Energy Fluxes to ITER Divertor and First Wall during Transients and Runaway Electron Loads

    International Nuclear Information System (INIS)

    Full text: The anticipated regime of the tokamak ITER is the H-mode in which the repetitive outbreaks of the edge-localized mode (ELM) produce plasma fluxes which determine the erosion rate and the lifetime of PFCs. The disruptions also reduce the PFC lifetime, despite of mitigation measures such as the massive gas injection (MGI), in particular because of high heat fluxes by runaway electrons and the radiation flush. The lost plasma dumped mainly into the scrape-off layer (SOL) produces surface erosion by sputtering, melting, splashing, cracking and vaporization. The expected transient heat fluxes on the PFCs are: Type I ELM 0.5 - 4 MJ/m2 on the timescale 0.3 - 0.6 ms, thermal quench flux 2 - 13 MJ/m2 in 1 - 3 ms. Mitigated disruption radiative flux 0.1 - 2 MJ/m2 in 2 - 5 ms, and the runaway flux more than 10 MJ/m2 on the timescale 10 - 100 ms. In ITER the CFC and tungsten macrobrush armour as PFCs for the divertor and the dome, and beryllium macrobrushes for the first wall (FW) are foreseen. The fluid motion in a thin molten layer of W and Be during transients may produce melt splashing and thus dust emission by droplets. The expected erosion of ITER PFCs can be properly estimated by numerical simulations validated against erosion experiments at the plasma gun facilities QSPA-T, MK-200UG and QSPA-Kh50. The measured material erosion was used to validate the melt dynamics code MEMOS and the thermomechanic code PEGASUS that were then applied to model the erosion of ITER PFCs under the anticipated transient loads. The results of experiments carried out at QSPA-T allowed validation of numerical model for the melt splashing based on Kelvin-Helmholtz-and Rayleigh-Taylor instabilities. The crack formation at W surface was modeled using the code PEGASUS and validated against the experiments carried out at QSPA-Kh50. The models were applied for simulations of PFCs damage under expected ITER-like scenarios. Numerical simulations under radiation and runaway electron impact

  5. Cascos utilizados por los pueblos de las estepas euroasiáticas en la época de los Escitas y de los Sármatas

    Directory of Open Access Journals (Sweden)

    Brentjes, B.

    2000-12-01

    Full Text Available The helmet appeared in the steppes of Eurasia at the end of the second mill. BC. The helmets were cast and seem to follow Chinese helmets of the Shang-Yin time. This type of helmet reached eastern Europe in the first centuries of the first mill. BC. A new development was the armoured cap of felt with iron casted scales.It was developed by the Skythians under the impression of the Assyrian scale armour which they met during their invasion in Near East. Three Assyrian pointed helmets were found in northern Caucasia and might be booty or bought by the Cimmerians or the Skythians in the Seventh or sixth century BC. During the fifth and fourth centuries the Greeks sold several types of helmets to the Skythians. Thrakian helmets might have been won during wars on the Balkans. Celtic helmets found at several sites might have been imported via Italy -or are left by Celtic mercenaries of the Pontos kings.

    El casco apareció en las estepas de Eurasia hacia el final del II milenio a.C. Los cascos eran forjados y parecen derivar de los cascos chinos del periodo Shang-Yin. Este tipo de casco alcanzó Europa oriental durante los primeros siglos del primer milenio a.C. Un nuevo desarrollo fue el capacete blindado de fieltro con escamas de hierro. Fue creado por los escitas bajo la influencia de las corazas asirias de escamas que encontraron durante sus incursiones en el Próximo Oriente. Tres cascos asirios apuntados han sido hallados en el norte del Cáucaso y podrían ser botín o adquisiciones de los Cimerios o los escitas durante los siglos VII-VI a.C. Durante los siglos V-IV a.C. los griegos vendieron diversos tipos de cascos a los Escitas. Cascos tracios pueden haber sido capturados durante campañas en los Balcanes. Cascos Célticos hallados en diversos yacimientos pudieron importarse via Italia -o haber pertenecido a mercenarios celtas de los reyes del Ponto.

  6. Temporally Dynamic, Spatially Static, Cobble Bedforms In Reversing Subtidal Currents

    Science.gov (United States)

    Abdulkade, Akirat; Carling, Paul; Zong, Quanli; Leyland, Julian; Thompson, Charlie

    2016-04-01

    Cobble bedforms, transverse to the reversing tidal currents, are exposed at extreme low-water Spring tides on an inter-tidal bedrock shelf in the macro-tidal Severn Estuary, UK. Near-bed flow velocities during Spring tides can exceed 1.5m/s, with water depths varying from zero to in excess of 10m. During neap tides the bedforms are not exposed, and sediment is expected to be of limited mobility. When exposed, the bedform geometry tends to be asymmetric; orientated down estuary with the ebb current. During Spring tides, vigorous bedload transport of gravel (including large cobbles) occurs during both flood and ebb over the crests and yet, despite this temporal dynamism, the bedforms remain spatially static over long time periods or show weak down-estuary migration. Stasis implies that the tidal bedload transport vectors are essentially in balance. Near-bed shear stress and bed roughness values vary systematically with the Spring-tide current speeds and the predicted grain-size of the bed load using the Shields criterion is in accord with observed coarser grain-sizes in transport. These hydrodynamic data, delimited by estimates of the threshold of motion, and integrated over either flood or ebb tides are being used to explain the apparent stability of the bedforms. The bulk hydraulic data are supplemented by particle tracer studies and laser-scanning of bed configurations between tides. The high-energy environment results in two forms of armouring. Pronounced steep imbrication of platy-cobbles visible on the exposed up-estuary side of dunes is probably disrupted during flood tides leading to rapid reworking of the toe deposits facing up-estuary. In contrast, some crest and leeside locations have been stable for prolonged periods such that closely-fitted fabrics result; these portions of the bedforms are static and effectively are 'armour-plated'. Ebb-tide deposits of finer, ephemeral sandy-units occur on the down estuary side of the bedforms. Sandy-units (although

  7. Ultrasonic test of carbon composite/copper joints in the ITER divertor

    International Nuclear Information System (INIS)

    Highlights: • ENEA developed and tested a specimen for the simulation of defects at the interface between CFC and copper. • The use of an ultrasonic technique properly set permitted to highlight and size with high accuracy the defects. • The technology developed could be employed successfully in the production of these components for high heat flux applications. -- Abstract: The vertical targets of the ITER divertor consist of high flux units (HFU) actively cooled: CuCrZr tubes armoured by tungsten and carbon/carbon fibre composite (CFC). The armour is obtained with holed parallelepiped blocks, called monoblocks, previously prepared and welded onto the tubes by means diffusion bonding. The monoblock preparation consists in the casting of a layer of copper oxygen free (Cu OFHC) inside the monoblock hole. Each HFU is covered with more than 100 monoblocks that have to be joined simultaneously to the tube. Therefore, it is very important to individuate any defects present in the casting of Cu OFHC or at the interface with the CFC before the monoblocks are installed on the units. This paper discusses the application of non-destructive testing by ultrasound (US) method for the control of the joining interfaces between CFC monoblocks and Cu OFHC, before the brazing on the CrCrZr tube. In ENEA laboratory an ultrasonic technique (UT) suitable for the control of these joints with size and geometry according to the ITER specifications has been developed and widely tested. Real defects in this type of joints are, however, still hardly detected by UT. The CFC surface has to be machined to improve the mechanical strength of the joint. This results in a surface not perpendicular to the ultrasonic wave. Moreover, CFC is characterized by high acoustic attenuation of the ultrasonic wave and then it is not easy to get information regarding the Cu/CFC bonding. Nevertheless, the UT sharpness and simplicity pushes to perform some further study. With this purpose, a sample with

  8. Decontamination of Cape Arza (Montenegro) from depleted Uranium

    International Nuclear Information System (INIS)

    On May 30, 1999, NATO A-10 aircrafts attacked Cape Arza, a very attractive touring area on peninsula Lustica, at the entrance of Boka Kotorska Bay, in Montenegro. They fired anti-armour rounds with penetrators made of depleted uranium. Such an armour-penetrating round has a length of 173 mm and a diameter of 30 mm. The bullet has an aluminium case (jacket) and inside it a conical DU penetrator. The length of the penetrator itself is 95 mm, and the diameter of its base is 16 mm. The penetrator weight is 292 g. According to the data reported by NATO (NATO, 2001), the total number of rounds fired against Cape Arza was 480. As to the data on combat mix of the A-10 aircraft gun, 300 (UNEP, 2001) or 400 (UNEP, 2001; FAS) of these rounds where with DU penetrators, and the rest with a classical charge. This means that Cape Arza was contaminated with 90 or 120 kg of DU, or with a radioactivity of (3.5 - 4.7) · 109 Bq. Depleted uranium is a waste product of the process of uranium enrichment in 235U isotope, for use in nuclear reactors or in nuclear weapons. The isotopic composition of depleted uranium is (Harley et al., 1999): (99.7 - 99.8) % of 238U, (0.2 - 0.3) % of 235U, 0.001 % of 234U, and only traces of 234Th, 234Pa and 231Th. If traces of the isotopes 236U, 239Pu and 240Pu are also present, as it is the case with DU from Cape Arza (UNEP, 2002), the depleted uranium is obtained by reprocessing of spent nuclear reactor fuel. The activity concentration of depleted uranium is 39.42 · 106 Bq/kg. Most of it comes from 238U and its decay products 234Th and 234Pa which are in radioactive equilibrium (12.27 · 106 Bq/kg per each of them), and the less part from 235U and 231Th (0.16 · 106 Bq/kg per each) (UNEP, 1999), while the activity concentration of 236U, 239Pu and 240Pu is below 100 Bq/kg (UNEP, 2001)

  9. Analysis of an ordinary bedload transport event in a mountain torrent (Rio Vanti, Verona, Italy)

    Science.gov (United States)

    Pastorello, Roberta; D'Agostino, Vincenzo

    2016-04-01

    The correct simulation of the sediment-transport response of mountain torrents both for extreme and ordinary flood events is a fundamental step to understand the process, but also to drive proper decisions on the protection works. The objective of this research contribution is to reconstruct the 'ordinary' flood event with the associated sediment-graph of a flood that caused on the 14th of October, 2014 the formation of a little debris cone (about 200-210 m3) at the junction between the 'Rio Vanti' torrent catchment and the 'Selva di Progno' torrent (Veneto Region, Prealps, Verona, Italy). To this purpose, it is important to notice that a great part of equations developed for the computation of the bedload transport capacity, like for example that of Schoklitsch (1962) or Smart and Jaeggi (1983), are focused on extraordinary events heavily affecting the river-bed armour. These formulas do not provide reliable results if used on events, like the one under analysis, not too far from the bankfull conditions. The Rio Vanti event was characterized by a total rainfall depth of 36.2 mm and a back-calculated peak discharge of 6.12 m3/s with a return period of 1-2 years. The classical equations to assess the sediment transport capacity overestimate the total volume of the event of several orders of magnitude. By the consequence, the following experimental bedload transport equation has been applied (D'Agostino and Lenzi, 1999), which is valid for ordinary flood events (q: unit water discharge; qc: unit discharge of bedload transport initiation; qs: unit bedload rate; S: thalweg slope): -qs-˜= 0,04ṡ(q‑ qc) S3/2 In particular, starting from the real rainfall data, the hydrograph and the sediment-graph have been reconstructed. Then, comparing the total volume calculated via the above cited equation to the real volume estimated using DoD techniques on post-event photogrammetric survey, a very satisfactory agreement has been obtained. The result further supports the thesis

  10. High heat flux actively cooled plasma facing components development, realization and first results in Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Grosman, A. [Association Euratom-CEA, Centre d' Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee

    2004-07-01

    The development, design, manufacture and testing of actively cooled high heat flux plasma facing components (PFC) has been an essential stage towards long powerful tokamak operations for Tore-Supra, it lasted about 10 years. This paper deals with the toroidal pumped limiter (TPL) that is able to sustain up to 10 MW/m{sup 2} of nominal heat flux. This device is based on hardened copper alloy heat sink structures covered by a carbon fiber composite armour, it resulted in the manufacturing of 600 elementary components, called finger elements, to achieve the 7.6 m{sup 2} TPL. This assembly has been operating in Tore-Supra since spring 2002. Some difficulties occurred during the manufacturing phase, the valuable industrial experience is summarized in the section 2. The permanent monitoring of PFC surface temperature all along the discharge is performed by a set of 6 actively cooled infrared endoscopes. The heat flux monitoring and control issue but also the progress made in our understanding of the deuterium retention in long discharges are described in the section 3. (A.C.)

  11. Nondestructive methods of analysis applied to oriental swords

    Directory of Open Access Journals (Sweden)

    Edge, David

    2015-12-01

    Full Text Available Various neutron techniques were employed at the Budapest Nuclear Centre in an attempt to find the most useful method for analysing the high-carbon steels found in Oriental arms and armour, such as those in the Wallace Collection, London. Neutron diffraction was found to be the most useful in terms of identifying such steels and also indicating the presence of hidden patternEn el Centro Nuclear de Budapest se han empleado varias técnicas neutrónicas con el fin de encontrar un método adecuado para analizar las armas y armaduras orientales con un alto contenido en carbono, como algunas de las que se encuentran en la Colección Wallace de Londres. El empleo de la difracción de neutrones resultó ser la técnica más útil de cara a identificar ese tipo de aceros y también para encontrar patrones escondidos.

  12. Experimental study of ELM-like heat loading on beryllium under ITER operational conditions

    Science.gov (United States)

    Spilker, B.; Linke, J.; Pintsuk, G.; Wirtz, M.

    2016-02-01

    The experimental fusion reactor ITER, currently under construction in Cadarache, France, is transferring the nuclear fusion research to the power plant scale. ITER’s first wall (FW), armoured by beryllium, is subjected to high steady state and transient power loads. Transient events like edge localized modes not only deposit power densities of up to 1.0 GW m-2 for 0.2-0.5 ms in the divertor of the machine, but also affect the FW to a considerable extent. Therefore, a detailed study was performed, in which transient power loads with absorbed power densities of up to 1.0 GW m-2 were applied by the electron beam facility JUDITH 1 on beryllium specimens at base temperatures of up to 300 °C. The induced damage was evaluated by means of scanning electron microscopy and laser profilometry. As a result, the observed damage was highly dependent on the base temperatures and absorbed power densities. In addition, five different classes of damage, ranging from ‘no damage’ to ‘crack network plus melting’, were defined and used to locate the damage, cracking, and melting thresholds within the tested parameter space.

  13. Dynamic Properties of RHA Steel under Planar Shock Loading using Explosive Driven Plate Impact System

    Directory of Open Access Journals (Sweden)

    B. Venkataramudu

    2015-05-01

    Full Text Available Planar shock loading of rolled homogeneous armour (RHA steel has been studied at high pressures in the range of 20-100 GPa using an explosive-driven plate impact system. Shock velocities and flyer velocities are measured using time of arrival pins embedded in the target at known depths. The shock equation of state of RHA steel has been determined. α → ε phase transition stress and hugoniot elastic limit (HEL of RHA steel have been determined through manganin gauge and found to be 12.2 ±0.6 GPa and 4.1 ± 0.2 GPa, respectively. The experimental stress of phase transition has been compared with the stress calculated using ThermoCalc software. The shock properties have been incorporated in the Autodyn simulation package and simulations were performed to determine flyer velocity, pressures and the results are compared with that of experiments.Defence Science Journal, Vol. 65, No. 3, May 2015, pp.196-202, DOI: http://dx.doi.org/10.14429/dsj.65.7952

  14. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Science.gov (United States)

    Kruszka, L.; Magier, M.

    2012-08-01

    The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity) in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it's particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot) and tungsten alloy (penetrator) are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ṡ 104s-1 (for aluminium alloy) and 6 ṡ 103s-1 (for tungsten alloy).

  15. Influence of Polymer Restraint on Ballistic Performanceof Alumina Ceramic Tiles

    Directory of Open Access Journals (Sweden)

    P.R.S. Reddy

    2008-03-01

    Full Text Available An experimental study has been carried out to evaluate the influence of confinement ofalumina ceramic tiles through polymer restraint, on its ballistic performance. Tiles of 99.5 per centpurity alumina were subjected to ballistic impact against 7.62 mm armour piercing projectiles atvelocities of about 820 m/s. The tiles of size 75 mm x 75 mm x 7 mm were confined on both facesby effectively bonding varying numbers of layers of polymer fabrics. These were then bondedto a 10 mm thick fibre glass laminate as a backing using epoxy resin. High performance polyethyleneand aramid polymer fabrics were used in the current set of experiments for restraining the tiles.Comparative effects of confinement on energy absorption of tiles with varied number of layersof fabrics were evaluated. It was observed that by providing effective confinement to the tile,energy absorption could be doubled with increase in areal density by about 13 per cent.Photographs of the damage and the effects of restraint on improvement in energy absorptionof ceramic tiles are presented and discussed.

  16. Powder metallurgical processing of self-passivating tungsten alloys for fusion first wall application

    International Nuclear Information System (INIS)

    Self-passivating tungsten based alloys are expected to provide a major safety advantage compared to pure tungsten, presently the main candidate material for first wall armour of future fusion reactors. In case of a loss of coolant accident with simultaneous air ingress, a protective oxide scale will be formed on the surface of W avoiding the formation of volatile and radioactive WO3. Bulk WCr12Ti2.5 alloys were manufactured by mechanical alloying (MA) and hot isostatic pressing (HIP), and their properties compared to bulk WCr10Si10 alloys from previous work. The MA parameters were adjusted to obtain the best balance between lowest possible amount of contaminants and effective alloying of the elemental powders. After HIP, a density >99% is achieved for the WCr12Ti2.5 alloy and a very fine and homogeneous microstructure with grains in the submicron range is obtained. Unlike the WCr10Si10 material, no intergranular ODS phase inhibiting grain growth was detected. The thermal and mechanical properties of the WCr10Si10 material are dominated by the silicide (W,Cr)5Si3; it shows a sharp ductile-to brittle transition in the range 1273–1323 K. The thermal conductivity of the WCr12Ti2.5 alloy is close to 50 W/mK in the temperature range of operation; it exhibits significantly higher strength and lower DBTT – around 1170 K – than the WCr10Si10 material

  17. On the imaging of land mines using 3+ - e- pair production

    International Nuclear Information System (INIS)

    The problem of disposing of abandoned land mines is very serious in many countries. Anti-personnel land mines (APM's) contain as little as 50 gram or less of explosive, which is enough to take off an adult's foot, or to kill a child. Anti-tank mines (ATM's), designed to penetrate the armour on the bottom of a tank, are much larger. Current techniques of finding them are not adequate. All practical high explosives contain 20% or more of nitrogen, which has a thermal neutron cross section of 75 mbarn, producing γ's of up to 10.8 MeV. The idea of using this property to detect explosives has been tested by others, but because of backgrounds is unable to find anything less than several hundred grams of explosive. The refinement proposed here is to convert the γs, track the resulting e+ - e- pairs in MWPC's, and use the information to locate the γ source, i.e. the mine. The directional information provided should reduce the backgrounds considerably. Result of an experimental test are presented, and possibilities for the future discussed. (author)

  18. Investigations in the area of thermonuclear structural material science in the Republic of Kazakhstan

    International Nuclear Information System (INIS)

    The investigations in the area of structural materials for fusion program initiated within the framework of ITER project in the Republic of Kazakhstan are devoted basically in the following direction: to studying the behaviour of hydrogen isotopes in structural elements of the first wall and the divertor in conditions simulating real conditions of material operation, accident situations arising during steam interaction with the beryllium armour of the first wall during accidental coolant loss, to establish an experimental facility for study aspects of tritium safety of thermonuclear installations, for example, levels of tritium accumulation and release; efficiency of barrier layers and protective coating; influence of brazing and welding zones on tritium permeation. The work on determination of tritium release from lead/lithium eutectic alloy by mass-spectrometry method and the development of permeation barriers has begun. At present, work has begun to create Kazakhstan's own tokamak type reactor for investigation of the behaviour of various first wall materials and divertor plates during normal and accident conditions. The concept of spherical tokamak will be used in the construction of KTM reactor. (author)

  19. Influences of high-flow events on a stream channel altered by construction of a highway bridge: a case study

    Science.gov (United States)

    Hedrick, Lara B.; Welsh, Stuart A.; Anderson, James T.

    2009-01-01

    Impacts of highway construction on streams in the central Appalachians are a growing concern as new roads are created to promote tourism and economic development in the area. Alterations to the streambed of a first-order stream, Sauerkraut Run, Hardy County, WV, during construction of a highway overpass included placement and removal of a temporary culvert, straightening and regrading of a section of stream channel, and armourment of a bank with a reinforced gravel berm. We surveyed longitudinal profiles and cross sections in a reference reach and the altered reach of Sauerkraut Run from 2003 through 2007 to measure physical changes in the streambed. During the four-year period, three high-flow events changed the streambed downstream of construction including channel widening and aggradation and then degradation of the streambed. Upstream of construction, at a reinforced gravel berm, bank erosion was documented. The reference section remained relatively unchanged. Knowledge gained by documenting channel changes in response to natural and anthropogenic variables can be useful for managers and engineers involved in highway construction projects.

  20. Joining and fabrication techniques for high temperature structures including the first wall in fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ho Jin; Lee, B. S.; Kim, K. B

    2003-09-01

    The materials for PFC's (Plasma Facing Components) in a fusion reactor are severely irradiated with fusion products in facing the high temperature plasma during the operation. The refractory materials can be maintained their excellent properties in severe operating condition by lowering surface temperature by bonding them to the high thermal conducting materials of heat sink. Hence, the joining and bonding techniques between dissimilar materials is considered to be important in case of the fusion reactor or nuclear reactor which is operated at high temperature. The first wall in the fusion reactor is heated to approximately 1000 .deg. C and irradiated severely by the plasma. In ITER, beryllium is expected as the primary armour candidate for the PFC's; other candidates including W, Mo, SiC, B4C, C/C and Si{sub 3}N{sub 4}. Since the heat affected zones in the PFC's processed by conventional welding are reported to have embrittlement and degradation in the sever operation condition, both brazing and diffusion bonding are being considered as prime candidates for the joining technique. In this report, both the materials including ceramics and the fabrication techniques including joining technique between dissimilar materials for PFC's are described. The described joining technique between the refractory materials and the dissimilar materials may be applicable for the fusion reactor and Generation-4 future nuclear reactor which are operated at high temperature and high irradiation.

  1. Apartheid en kapitalisme : Simbiose of disfunksionele verhouding?

    Directory of Open Access Journals (Sweden)

    P. Nel

    1985-03-01

    Full Text Available The author refers to the fact that Marxist analyses have a way of promoting cynicism, and states that if one chooses to go through life armoured in illusion, this type of analysis should be avoided at all costs. He refers to a method of analysis which undertakes a thorough re-evaluation of South African history of the past century which uses, broadly speaking, insights based on Marxism. A discussion of this method forms the theme of this paper. This discussion centres on the Marxist typification of the South African social structure as a capitalist one with specific characteristics, and on the view of this approach which indicates the close relationship between capitalist development and political policies in the country. In the final analysis attention is directed to the need for taking serious note of this approach in terms of the fact that a Marxist approach can provide a valid perspective on South African history. There is also a need to take cognizance of this approach in view of the fact that this approach reflects the experience of a large part of the population. The author points out that the question as to whether apartheid and capitalism can be said to stand in a disfunctional relationship is seriously questioned, and he concludes by maintaining that a precondition for dialogue with all Blacks in South Africa is to be found in the necessity of gaining clarity about the validity of our own preconceptions.

  2. 187-gene phylogeny of protozoan phylum Amoebozoa reveals a new class (Cutosea) of deep-branching, ultrastructurally unique, enveloped marine Lobosa and clarifies amoeba evolution.

    Science.gov (United States)

    Cavalier-Smith, Thomas; Chao, Ema E; Lewis, Rhodri

    2016-06-01

    Monophyly of protozoan phylum Amoebozoa, and subdivision into subphyla Conosa and Lobosa each with different cytoskeletons, are well established. However early diversification of non-ciliate lobose amoebae (Lobosa) is poorly understood. To clarify it we used recently available transcriptomes to construct a 187-gene amoebozoan tree for 30 species, the most comprehensive yet. This robustly places new genus Atrichosa (formerly lumped with Trichosphaerium) within lobosan class Tubulinea, not Discosea as previously supposed. We identified an earliest diverging lobosan clade comprising marine amoebae armoured by porose scaliform cell-envelopes, here made a novel class Cutosea with two pseudopodially distinct new families. Cutosea comprise Sapocribrum, ATCC PRA-29 misidentified as 'Pessonella', plus from other evidence Squamamoeba. We confirm that Acanthamoeba and ATCC 50982 misidentified as Stereomyxa ramosa are closely related. Discosea have a strongly supported major subclade comprising Thecamoebida plus Glycostylida (suborders Dactylopodina, Stygamoebina; Vannellina) phylogenetically distinct from Centramoebida. Stygamoeba is sister to Dactylopodina. Himatismenida are either sister to Centramoebida or deeper branching. Discosea usually appear holophyletic (rarely paraphyletic). Paramoeba transcriptomes include prokinetoplastid Perkinsela-like endosymbiont sequences. Cunea, misidentified as Mayorella, is closer to Paramoeba than Vexillifera within holophyletic Dactylopodina. Taxon-rich site-heterogeneous rDNA trees confirm cutosan distinctiveness, allow improved conosan taxonomy, and reveal previous dictyostelid tree misrooting. PMID:27001604

  3. Data merging of infrared and ultrasonic images for plasma facing components inspection

    International Nuclear Information System (INIS)

    For steady-state magnetic thermonuclear fusion devices which need large power exhaust capability, actively cooled plasma facing components have been developed. In order to guarantee the integrity of these components during the required lifetime, their thermal and mechanical behaviour must be assessed. Before the procurement of the ITER Divertor, the examination of the heat sink to armour joints with non-destructive techniques is an essential topic to be addressed. Defects may be localised at different bonding interfaces. In order to improve the defect detection capability of the SATIR technique, the possibility of merging the infrared thermography test data coming from SATIR results with the ultrasonic test data has been identified. The data merging of SATIR and ultrasonic results has been performed on Carbon Fiber Composite (CFC) monoblocks with calibrated defects, identified by their position and extension. These calibrated defects were realised with machining, with 'stop-off' or by a lack of CFC activation techniques, these last two representing more accurately a real defect. A batch of 56 samples was produced to simulate each possibility of combination with regards to interface location, position and extension and way of realising the defect. The use of a data merging method based on Dempster-Shafer theory improves significantly the detection sensibility and reliability of defect location and size.

  4. Effect of off-normal events on the reactor first wall

    International Nuclear Information System (INIS)

    In this paper, we analyse the energy deposition and erosion of the W/EUROFER blanket module for the first wall (FW) of DEMO due to the runaway electrons (RE) and vertical displacements events (VDEs). The DEMO data for transients were extrapolated from ITER data by using the scaling arguments. The simulations were performed at an RE deposition energy in the range 30-100 MJ m-2 over 0.05-0.3 s. In the case of a 'hot' VDE, all stored plasma energy is deposited on the FW area for ∼1 s. For a VDE following the thermal quench phase the remaining magnetic energy is deposited on the FW for ∼0.3 s. It is shown that the minimum W thickness needed for preventing failure of the W/EUROFER bond (assumed to be the EUROFER creep point) is large enough, causing armour melting. Both RE and VDE in DEMO will pose a major life-time issue depending on their frequency.

  5. The steady-state ECRH-system at Wendelstein7-X

    International Nuclear Information System (INIS)

    Electron Cyclotron Resonance Heating (ECRH) is the main heating system for the Wendelstein7-X (W7-X) stellarator and the only one for CW-operation in the first stage. The mission of W7-X, which is presently under construction at IPP-Greifswald, is to demonstrate the inherent steady state capability of stellarators at reactor relevant plasma parameters. A modular 10 MW ECRH plant at 140 GHz with 1 MW CW-capability power for each module is under construction to meet the scientific objectives. Simulations of different ECRH scenarios, which are foreseen for W7-X operation and base on ray- tracing calculations and confinement studies, will be presented. A steady state ECRH has specific requirements on the stellarator machine itself, on the ECRH-sources, transmissions elements and on the experimental environment. In particular all elements have to be sufficiently cooled, screened and armoured against microwaves. The commissioning of the ECRH plant is well under way, the strategy and status of the project will be reported. First full power, CW integral tests of one ECRH module have been performed. A large microwave stray radiation chamber for integrated in-vessel component tests had been brought into operation. A bi-axially movable, motor driven ECRH antenna mock-up was build and is tested for reliability now. A strategy for the commissioning and the first experimental campaign at W7-X has been developed. (author)

  6. Joining and fabrication techniques for high temperature structures including the first wall in fusion reactor

    International Nuclear Information System (INIS)

    The materials for PFC's (Plasma Facing Components) in a fusion reactor are severely irradiated with fusion products in facing the high temperature plasma during the operation. The refractory materials can be maintained their excellent properties in severe operating condition by lowering surface temperature by bonding them to the high thermal conducting materials of heat sink. Hence, the joining and bonding techniques between dissimilar materials is considered to be important in case of the fusion reactor or nuclear reactor which is operated at high temperature. The first wall in the fusion reactor is heated to approximately 1000 .deg. C and irradiated severely by the plasma. In ITER, beryllium is expected as the primary armour candidate for the PFC's; other candidates including W, Mo, SiC, B4C, C/C and Si3N4. Since the heat affected zones in the PFC's processed by conventional welding are reported to have embrittlement and degradation in the sever operation condition, both brazing and diffusion bonding are being considered as prime candidates for the joining technique. In this report, both the materials including ceramics and the fabrication techniques including joining technique between dissimilar materials for PFC's are described. The described joining technique between the refractory materials and the dissimilar materials may be applicable for the fusion reactor and Generation-4 future nuclear reactor which are operated at high temperature and high irradiation

  7. Integral experiment on effects of large opening in fusion reactor blanket on tritium breeding using annular geometry

    International Nuclear Information System (INIS)

    An experiment involving a simulated blanket with an opening has been performed using the line source and annular blanket system developed under the JAERI/USDOE collaborative programme in order to examine the effects of the opening on neutronics parameters such as the tritium-breeding ratio. The annular test assembly was rectangular in shape and consisted of a lithium oxide blanket covered with graphite and SS304 which simulated the graphite armour plate and first wall in a fusion device. A large opening (376mm x 425.5mm) was made in the middle of the test blanket. This opening simulated a neutral beam injector.Tritium production rates and reaction rates were measured inside the blanket. Neutron spectra and reaction rates were also measured on the surfaces of both sides and without the opening of the inner cavity. The opening decreased the number of low energy neutrons contained in the cavity and especially decreased 6Li tritium production by 10% inside the blanket at the opposite side of the opening. The Monte Carlo code GMVP using the JENDL-3 nuclear data library predicted the measured nuclear parameters in the test blankets, such as the tritium production rate, to within 10% accuracy. (orig.)

  8. Delamination toughness of ultra high molecular weight polyethylene (UHMWPE) composites

    Science.gov (United States)

    Porras, A.; Tellez, J.; Casas-Rodriguez, J. P.

    2012-08-01

    Ultra high molecular weight polyethylene (UHMWPE) fibre reinforced composites are an important group of material for armours solutions, where their unique combination of properties could be utilized. A commonly observed failure mode in this kind of unidirectional laminated composites under impact ballistic is delamination between the composite layers. In the present study, an investigation on the delamination toughness behaviour exhibited by UHMWPE composites laminated was made. The interlaminar Mode II critical strain energy release rates of (UHMWPE) fibre reinforced composites were characterized using the End Notch Flexural (ENF) test. Critical strain energy release rate was obtained from the load - deflection test data using the beam theory expression. It was found that the energy release rate of the composite exhibited a very low value of around 60J/m2 using a moulding pressure of approximately 1200 psi. In order to analyse the delamination resistance of composite, the effects of changing the manufacture process variables and the use of a thermoplastic adhesive film in the composites were investigated. The composite laminates were produced by hot compressing moulding using a film-stacking procedure. It was found that the damage resistance of the UHMWPE composite was influenced by the manufacture method, which affects the Mode II interlaminar fracture toughness and the ballistic response of composites.

  9. Delamination toughness of ultra high molecular weight polyethylene (UHMWPE composites

    Directory of Open Access Journals (Sweden)

    Casas-Rodriguez J.P.

    2012-08-01

    Full Text Available Ultra high molecular weight polyethylene (UHMWPE fibre reinforced composites are an important group of material for armours solutions, where their unique combination of properties could be utilized. A commonly observed failure mode in this kind of unidirectional laminated composites under impact ballistic is delamination between the composite layers. In the present study, an investigation on the delamination toughness behaviour exhibited by UHMWPE composites laminated was made. The interlaminar Mode II critical strain energy release rates of (UHMWPE fibre reinforced composites were characterized using the End Notch Flexural (ENF test. Critical strain energy release rate was obtained from the load – deflection test data using the beam theory expression. It was found that the energy release rate of the composite exhibited a very low value of around 60J/m2 using a moulding pressure of approximately 1200 psi. In order to analyse the delamination resistance of composite, the effects of changing the manufacture process variables and the use of a thermoplastic adhesive film in the composites were investigated. The composite laminates were produced by hot compressing moulding using a film-stacking procedure. It was found that the damage resistance of the UHMWPE composite was influenced by the manufacture method, which affects the Mode II interlaminar fracture toughness and the ballistic response of composites.

  10. Finite element analysis of the high strain rate testing of polymeric materials

    Science.gov (United States)

    Gorwade, C. V.; Alghamdi, A. S.; Ashcroft, I. A.; Silberschmidt, V. V.; Song, M.

    2012-08-01

    Advanced polymer materials are finding an increasing range of industrial and defence applications. Ultra-high molecular weight polymers (UHMWPE) are already used in lightweight body armour because of their good impact resistance with light weight. However, a broader use of such materials is limited by the complexity of the manufacturing processes and the lack of experimental data on their behaviour and failure evolution under high-strain rate loading conditions. The current study deals with an investigation of the internal heat generation during tensile of UHMWPE. A 3D finite element (FE) model of the tensile test is developed and validated the with experimental work. An elastic-plastic material model is used with adiabatic heat generation. The temperature and stresses obtained with FE analysis are found to be in a good agreement with the experimental results. The model can be used as a simple and cost effective tool to predict the thermo-mechanical behaviour of UHMWPE part under various loading conditions.

  11. The Tore Supra toroidal pump limiter: experience feedback of HHF elements series manufacture

    International Nuclear Information System (INIS)

    Since 1992, reliable High Heat Flux PFCs based on copper alloy heat sink structures and a CFC armour, have been developed. The final result is an actively cooled high heat flux element that is capable of removing up to 10 MW.m-2 in stationary operating conditions. About 600 of these high performance individual components have then been manufactured and assembled in order to equip a Toroidal Pump Limiter (TPL). The final deliveries was successfully achieved end of 2001. The paper deals with the experience feedback built-up along the four years duration of the TPL components manufacture. We will show where issues were encountered, how solutions were found to achieve the fabrication of components and will highlight what are the main technical lessons to be learned: acceptance criteria, choice of materials, margins of processes. Finally a proposal of an alternative optimised design is presented, fruit of the experience gained from this up to now, unique series manufacture of actively cooled plasma facing HHF components. We believe that such experience will certainly be of use to ITER as well as to Wendelstein 7-X as far as PFC is concerned. (authors)

  12. 基于KPI在医院行政后勤部门的绩效考核管理体系构建%The Construction of Performance Appraisal Management System in the Hospital based on the KPI Administrative Departments

    Institute of Scientific and Technical Information of China (English)

    范艺馨; 续小霞; 张茹雪; 白靖平

    2015-01-01

    Performance appraisal has become a hot issue. How to carry out the performance appraisal,improve the work efficiency, promote the innovation in health service management,standard administrative behavior in the health functions of the administrative organs and institutions has become a major problem in the development of the hospital. A 3 armour hospital in xinjiang sets up logistics department performance appraisal to the administration management system from the BSC′s financial,customer,internal business and learning growth four aspects based on the KPI,so as to provide reference for other hospitals performance reform.%绩效考核已经成为热点问题。如何在卫生行政机关及事业单位职能部门开展绩效考核,提高工作效率,推进卫生事业管理创新,规范行政行为,已经成为医院发展中的重大难题。新疆某三甲医院主要从BSC的财务、客户、内部运营和学习成长4个方面出发,基于KPI建立针对行政后勤部门绩效考核管理体系,以期为其他医院绩效改革提供参考。

  13. Finite Element Analysis Of Large Deformation Of Articular Cartilage In Upper Ankle Joint Of Occupant In Military Vehicles During Explosion

    Directory of Open Access Journals (Sweden)

    Klekiel T.

    2015-09-01

    Full Text Available The paper presents the analysis of the load of lower limbs of occupants in the armoured military vehicle, which has been destroyed by detonation of the Improvised Explosive Device (IED charge under the vehicle. A simplified model of the human lower limb focused on upper ankle joint was developed in order to determine the reaction forces in joints and load in particular segments during the blast load. The model of upper ankle joint, include a tibia and an ankle bone with corresponding articular cartilage, has been developed. An analysis of the stress distribution under the influence of forces applied at different angles to the biomechanical axis of a limb has been performed. We analyzed the case of the lower limb of a sitting man leaning his feet on the floor. It has been shown that during a foot pronation induced by a knee outward deviation, the axial load on the foot causes significantly greater tension in the tibia. At the same time it has been shown that within the medial malleolus, tensile stresses occur on the surface of the bone which may lead to fracture of the medial malleolus. It is a common case of injuries caused by loads on foot of passengers in armored vehicles during a mine or IED load under the vehicle. It was shown that the outward deviation of the knee increases the risk of the foot injury within the ankle joint.

  14. Influence of environmental parameters and of their interactions on the release of metal(loid)s from a construction material in hydraulic engineering.

    Science.gov (United States)

    Schmukat, A; Duester, L; Goryunova, E; Ecker, D; Heininger, P; Ternes, T A

    2016-03-01

    Besides the leaching behaviour of a construction material under standardised test-specific conditions with laboratory water, for some construction materials it is advisable to test their environmental behaviour also under close to end use conditions. The envisaged end use combined with the product characteristics (e.g. mineral phases) is decisive for the choice of environmental factors that may change the release of substance that potentially cause adverse environmental effects (e.g. fertilisation or ecotoxicity). At the moment an experimental link is missing between mono-factorial standardised test systems and non standardised complex incubation experiments such as mesocosms which are closer to environmental conditions. Multi-factorial batch experiments may have the potential to close the gap. To verify this, batch experiments with copper slag were performed which is used as armour stones in hydraulic engineering. Design of experiments (DoE) was applied to evaluate the impact of pH, ionic strength, temperature and sediment content on the release of As, Cu, Mo, Ni, Pb, Sb and Zn. The study shows that release and sediment-eluent partitioning of metal(loid)s are impacted by interactions between the studied factors. Under the prevalent test conditions sediment acts as a sink enhancing most strongly the release of elements from the material. PMID:26546704

  15. Tritium retention in candidate next-step protection materials: engineering key issues and research requirements

    International Nuclear Information System (INIS)

    Although a considerable volume of valuable data on the behaviour of tritium in beryllium and carbon-based armours exposed to hydrogenic fusion plasmas has been compiled over the past years both from operation of present-day tokamaks and from laboratory simulations, knowledge is far from complete and tritium inventory predictions for these materials remain highly uncertain. In this paper we elucidate the main mechanisms responsible for tritium trapping and release in next-step D-T tokamaks, as well as the applicability of some of the presently known data bases for design purposes. Owing to their strong anticipated implications on tritium uptake and release, attention is focused mainly on the interaction of tritium with neutron damage induced defects, on tritium codeposition with eroded carbon and on the effects of oxide and surface contaminants. Some preliminary quantitative estimates are presented based on most recent experimental findings and latest modelling developments as well. The influence of important working conditions such as target temperature, loading particle fluxes, erosion and redeposition rates, as well as material characteristics such as the type of morphology of the protection material (i.e. amorphous plasma-sprayed beryllium vs. solid forms), and design dependent parameters are discussed in this paper. Remaining issues which require additional effort are identified. (orig.)

  16. A new trigonotarbid arachnid from the Coal Measures of Hagen-Vorhalle, Germany

    Directory of Open Access Journals (Sweden)

    J. A. Dunlop

    2006-02-01

    Full Text Available A new trigonotarbid (Arachnida: Trigonotarbida: Trigonotarbidae is described as Archaeomartus roessleri n. sp. from the Upper Carboniferous (Pennsylvanian; Namurian B, higher Marsdenian of Hagen-Vorhalle, Germany. Originally assigned to Trigonotarbus johnsoni Pocock, 1911, our new fossil has a distinctly lobed carapace and thus resembles more closely the Early Devonian species Archaeomartus levis Størmer, 1970. In carapace morphology Archaeomartus approaches the condition seen in the larger and more heavily-armoured taxa Eophrynidae, Kreischeriidae and Aphantomartidae. Thus we provisionally resolve Archaeomartus as sister-group to this probably monophyletic trio of families and discuss the possibility that Trigonotarbidae may be paraphyletic. Ein neuer Trigonotarbiden-Fund (Arachnida: Trigonotarbida: Trigonotarbidae aus dem Ober-Karbon (Pennsylvanium; Namurium B, höheres Marsdenium von Hagen-Vorhalle, Deutschland, wird als Archaeomartus roessleri n. sp. beschrieben. Bei der Erst-Dokumentation wurde er noch zu Trigonotarbus johnsoni Pocock, 1911 gestellt; er unterscheidet sich hiervon aber durch die deutlichen Loben auf dem Carapax und ähnelt damit eher dem unterdevonischen Archaeomartus levis Størmer, 1970. In der Carapax-Morphologie nähert sich Archaeomartus mehr den größeren und kräftiger skulptierten Eophrynidae, Kreischeriidae und Aphantomartidae. Daher fassen wir Archaeomartus zumindest vorläufig als Schwestergruppe dieser wahrscheinlich monophyletischen Familien-Dreiergruppe auf; die Trigonotarbidae könnten somit paraphyletisch sein. doi:10.1002/mmng.200600004

  17. Shell matrix proteins of the clam, Mya truncata: Roles beyond shell formation through proteomic study.

    Science.gov (United States)

    Arivalagan, Jaison; Marie, Benjamin; Sleight, Victoria A; Clark, Melody S; Berland, Sophie; Marie, Arul

    2016-06-01

    Mya truncata, a soft shell clam, is presented as a new model to study biomineralization through a proteomics approach. In this study, the shell and mantle tissue were analysed in order to retrieve knowledge about the secretion of shell matrix proteins (SMPs). Out of 67 and 127 shell and mantle proteins respectively, 16 were found in both shell and mantle. Bioinformatic analysis of SMP sequences for domain prediction revealed the presence of several new domains such as fucolectin tachylectin-4 pentraxin-1 (FTP), scavenger receptor, alpha-2-macroglobulin (α2 M), lipocalin and myosin tail along with previously reported SMP domains such as chitinase, carbonic anhydrase, tyrosinase, sushi, and chitin binding. Interestingly, these newly predicted domains are attributed with molecular functions other than biomineralization. These findings suggest that shells may not only act as protective armour from predatory action, but could also actively be related to other functions such as immunity. In this context, the roles of SMPs in biomineralization need to be looked in a new perspective. PMID:27068305

  18. High heat flux actively cooled plasma facing components development, realization and first results in Tore Supra

    International Nuclear Information System (INIS)

    The development, design, manufacture and testing of actively cooled high heat flux plasma facing components (PFC) has been an essential stage towards long powerful tokamak operations for Tore-Supra, it lasted about 10 years. This paper deals with the toroidal pumped limiter (TPL) that is able to sustain up to 10 MW/m2 of nominal heat flux. This device is based on hardened copper alloy heat sink structures covered by a carbon fiber composite armour, it resulted in the manufacturing of 600 elementary components, called finger elements, to achieve the 7.6 m2 TPL. This assembly has been operating in Tore-Supra since spring 2002. Some difficulties occurred during the manufacturing phase, the valuable industrial experience is summarized in the section 2. The permanent monitoring of PFC surface temperature all along the discharge is performed by a set of 6 actively cooled infrared endoscopes. The heat flux monitoring and control issue but also the progress made in our understanding of the deuterium retention in long discharges are described in the section 3. (A.C.)

  19. Megatherium, the stabber.

    Science.gov (United States)

    Fariña, R A; Blanco, R E

    1996-12-22

    The traditional point of view that fossil ground sloths (Xenarthra) were a relatively uniform, ecologically little diverse group has been recently challenged. Marine habits have been ascribed to Thalassocnus natans of the Pliocene of Peru. Also, a more diverse diet has been proposed by one of us (R.A.F.) for some Lujanian (late Pleistocene-early Holocene of South America genera of ground sloths. In this paper, an aspect of this latter hypothesis is tested, i.e. that Megatherium americanum had morphological features that are better explained by its having had carnivorous habits rather than by solely herbivorous ones. Specifically, the question of its forearms having been designed for optimizing speed rather than strength of extension is addressed. Such a trait might have been associated with a potentially aggressive use of the animal large claws, whereas a strong extension would be more proper for tearing branches out. On the other hand the high mechanical advantage of the biceps might have made it possible for the animal to have lifted and carried heavy weights. This in turn, suggests the possibility that the animal could have manipulated large prey (for instance, turning dorsally armoured preys or carcasses upside down to expose softer parts and cached large food pieces in a safer place. By this view, Megatherium americanum would be the largest land mammal hunter to have existed. PMID:9025315

  20. Development of tungsten fibre-reinforced tungsten composites towards their use in DEMO—potassium doped tungsten wire

    Science.gov (United States)

    Riesch, J.; Han, Y.; Almanstötter, J.; Coenen, J. W.; Höschen, T.; Jasper, B.; Zhao, P.; Linsmeier, Ch; Neu, R.

    2016-02-01

    For the next step fusion reactor the use of tungsten is inevitable to suppress erosion and allow operation at elevated temperature and high heat loads. Tungsten fibre-reinforced composites overcome the intrinsic brittleness of tungsten and its susceptibility to operation embrittlement and thus allow its use as a structural as well as an armour material. That this concept works in principle has been shown in recent years. In this contribution we present a development approach towards its use in a future fusion reactor. A multilayer approach is needed addressing all composite constituents and manufacturing steps. A huge potential lies in the optimization of the tungsten wire used as fibre. We discuss this aspect and present studies on potassium doped tungsten wire in detail. This wire, utilized in the illumination industry, could be a replacement for the so far used pure tungsten wire due to its superior high temperature properties. In tensile tests the wire showed high strength and ductility up to an annealing temperature of 2200 K. The results show that the use of doped tungsten wire could increase the allowed fabrication temperature and the overall working temperature of the composite itself.

  1. MAST Upgrade - Construction Status

    CERN Document Server

    Milnes, Joe; Dhalla, Fahim; Fishpool, Geoff; Hill, John; Katramados, Ioannis; Martin, Richard; Naylor, Graham; O'Gorman, Tom; Scannell, Rory

    2015-01-01

    The Mega Amp Spherical Tokamak (MAST) is the centre piece of the UK fusion research programme. In 2010, a MAST Upgrade programme was initiated with three primary objectives, to contribute to: 1) Testing reactor concepts (in particular exhaust solutions via a flexible divertor allowing Super-X and other extended leg configurations); 2) Adding to the knowledge base for ITER (by addressing important plasma physics questions and developing predictive models to help optimise ITER performance of ITER) and 3) Exploring the feasibility of using a spherical tokamak as the basis for a fusion Component Test Facility. With the project mid-way through its construction phase, progress will be reported on a number of the critical subsystems. This will include manufacture and assembly of the coils, armour and support structures that make up the new divertors, construction of the new set coils that make up the centre column, installation of the new power supplies for powering the divertor coils and enhanced TF coil set, progr...

  2. The paradoxical marketing of sports equipment brands. [El marketing paradójico de las marcas de material deportivo].

    Directory of Open Access Journals (Sweden)

    José A. Martínez

    2014-01-01

    Full Text Available As Ko (2013 pointed out, the sport industry is a large and fast growing business. The U.S. market accounted for as much as $400-435 billion in 2012. Sports equipment companies provide the products required to practice and enjoy sports: clothing, footwear, and other apparel and gear. Therefore, sports equipment brands surround all the aspects shaping the sports industry. In addition, they extend their arms to also embrace the fashion market. A few equipment brands, such as Nike and Adidas are listed among the most powerful brands in the world (Badenhausen, 2012. Data about some giant brands of this industry reflect the relevance of this business. For example, Nike global sales were to $21 billion in 2011, (Cendrowski, 2012; Under Armour spent $205.4 million on marketing in 2012 (Lambert, 2013 and Nike $2.4 billion in 2011 (Cendrowski, 2012; The football teams Real Madrid and Barcelona get an average of $49 million a year from Adidas and $43 million from Nike, respectively (Ozanian, 2012; and Adidas paid $130 million to become the official sportswear provider of London 2012 summer Olympics (Anderson, 2013.

  3. A subaqueous eruption model for shallow-water, small volume eruptions: Evidence from two Precambrian examples

    Science.gov (United States)

    Mueller, Wulf U.

    Ancient, shallow-water, pyroclastic deposits are identified in the Paleoproterozoic Ketilidian Mobile belt, southeast Greenland at Kangerluluk and in the Neoproterozoic Gariep belt of Namibia in the Schakalsberg Mountains. The 1-30 m-thick tuff and lapilli tuff deposits are interpreted as eruption-fed density current deposits emanating from tephra jets that collapsed under subaqueous conditions due to water ingress. The presence of 1-10 mm diameter armoured lapilli, with a central vesicular lapillus or shard, suggests the existence of high velocity, gas, water vapour, and particle-rich tephra jets. A transition from a gas-steam supported tephra jet to a cold water-laden density current without an intermediate stage of storage and remobilization is inferred. Interpretation of a 5-15 m-thick lapilli tuff breccia further supports explosive subaqueous mechanisms. Pyroclasts in the lapilli tuff breccia are interpreted as bombs emplaced ballistically. Multiple bomb sags produced by the impact of rounded juvenile crystal-rich pyroclasts required a water-exclusion zone formed either by a continuous magma uprush or multiple jet activity occurring concurrently, rather than as isolated tephra jets. Intercalated density current deposits indicate uprush events of limited duration and their recurrence with rapid collapse after each pulse. A new subaqueous Surtseyan-type eruption model is proposed based on observations from these two Precambrian study areas.

  4. Bedload transport in a river confluence

    Science.gov (United States)

    Martín-Vide, J. P.; Plana-Casado, A.; Sambola, A.; Capapé, S.

    2015-12-01

    The confluence of the regulated Toltén River and its tributary the unregulated Allipén (south of Chile) has proved dynamic in the last decade. Daily bedload measurements with a Helley-Smith sampler, bed surveys, and grain-size distributions of the two rivers are obtained from a field campaign that lasts 3 months in high-flow season. The goals are to quantify total bedload and to understand the balance between tributary and main river and the bedload distribution in space and texture. The bedload transport varies 200-fold, with a maximum of 5000 t/day. The discharge varies five-fold, with a maximum of 900 m3/s. Two-thirds of the total bedload volume are transported through the deeper area of the cross section and gravel is predominant (64%). Average bedload volumes in the confluence seem unbalanced in favour of the tributary. Main river bedload transport is predominantly at below-capacity conditions, while the tributary bedload transport is at-capacity conditions. This is deemed the main reason of inaccuracy of the bedload predictors. The roles of entrainment into suspension, helical flow, partial transport, and mobile armour are discussed.

  5. Feature selection for neural network based defect classification of ceramic components using high frequency ultrasound.

    Science.gov (United States)

    Kesharaju, Manasa; Nagarajah, Romesh

    2015-09-01

    The motivation for this research stems from a need for providing a non-destructive testing method capable of detecting and locating any defects and microstructural variations within armour ceramic components before issuing them to the soldiers who rely on them for their survival. The development of an automated ultrasonic inspection based classification system would make possible the checking of each ceramic component and immediately alert the operator about the presence of defects. Generally, in many classification problems a choice of features or dimensionality reduction is significant and simultaneously very difficult, as a substantial computational effort is required to evaluate possible feature subsets. In this research, a combination of artificial neural networks and genetic algorithms are used to optimize the feature subset used in classification of various defects in reaction-sintered silicon carbide ceramic components. Initially wavelet based feature extraction is implemented from the region of interest. An Artificial Neural Network classifier is employed to evaluate the performance of these features. Genetic Algorithm based feature selection is performed. Principal Component Analysis is a popular technique used for feature selection and is compared with the genetic algorithm based technique in terms of classification accuracy and selection of optimal number of features. The experimental results confirm that features identified by Principal Component Analysis lead to improved performance in terms of classification percentage with 96% than Genetic algorithm with 94%. PMID:26081920

  6. Utilizing steel slag in environmental application - An overview

    Science.gov (United States)

    Lim, J. W.; Chew, L. H.; Choong, T. S. Y.; Tezara, C.; Yazdi, M. H.

    2016-06-01

    Steel slags are generated as waste material or byproduct every day from steel making industries.The potential environmental issues which are related with the slag dump or reprocessing for metal recovery are generally being focused in the research. However the chemistry and mineralogy of slag depends on metallurgical process which is able to determine whether the steel slag can be the reusable products or not. Nowadays, steel slag are well characterized by using several methods, such as X-ray Diffraction, ICP-OES, leaching test and many more. About the industrial application, it is mainly reused as aggregate for road construction, as armour stones for hydraulic engineering constructions and as fertilizers for agricultural purposes. To ensure the quality of steel slag for the end usage, several test methods are developed for evaluating the technical properties of steel slag, especially volume stability and environmental behaviour. In order to determine its environmental behaviour, leaching tests have been developed. The focus of this paper however is on those applications that directly affect environmental issues including remediation, and mitigation of activities that negatively impact the environment.

  7. A high selective cataluminescence sensor for the determination of tetrahydrofuran vapor

    International Nuclear Information System (INIS)

    A novel tetrahydrofuran (THF) vapor sensor was designed based on the cataluminescence (CTL) of THF on nanosized γ-Al2O3/MgO (mol ratio = 1.5:1). SEM and XRD were applied for its characterization. We found that the CTL was strongly produced when THF vapor flowed through a nanosized Al–Mg mixed-metal oxide surface, while the CTL was weakly generated when THF vapor flowed through a single nanosized γ-Al2O3 or MgO surface. Quantitative analysis was performed at an optimal temperature of 279 °C, a wavelength of 460 nm and a flow rate of 360 mL min−1. The linear range of the CTL intensity versus concentrations of THF vapor was 1.0–3000 mL m−3 with a detection limit of 0.67 mL m−3. No (or only very low) interference was observed by formaldehyde, methanol, ethanol, benzene, toluene, ethyl acetate, ammonia, cyclohexane, chloroform, glycol armour ether, glycol ether, isopropyl ether and n-butyl ether or acetic acid. Since the response of the sensor was rapid and the system was easy to handle, we believe that the sensor has great potential for real-world use. (paper)

  8. Experience in production works by X-ray radiometric logging to improve the confidence of borehole cross section sampling for zinc and lead

    International Nuclear Information System (INIS)

    An experiment on the application of roentgenoradiometric logging (RRL) for simultaneous determination of lead and zinc in prospecting boreholes is described. The measurements were made with a GKS-IH spectrometer equipped with modernized logging SP-4 probes of 42 mm in diameter with external units and CPM-19 counters. A radioactive armoured cable KRK-2 was used for transmitting information, the diagrams being recorded on an PR-6 photorecorder. The characteristic lines of the K-series of zinc and the L-series of lead, as well as singly scattered source radiation were recorded. The ranges of the recorded energies were 7-10, 10-15, and 18-21 keV. The spectrometer resolution for the zinc line was 20-23%. The portion of the integral spectrum of the working source with an energy of over 40 keV from the 87-keV line of cadmium-109 was used as a gamma reference. As a result of the investigation it was concluded that the sensitivity threshold of RRL is 3-5 times lower than the limiting content for overbalance ores and meets the prospecting requirements. The errors in the estimate of the contents and linear resources from RRL are commensurate with those of qualitative geological testing

  9. Depleted uranium instead of lead in munitions: the lesser evil

    International Nuclear Information System (INIS)

    Uranium has many similarities to lead in its exposure mechanisms, metabolism and target organs. However, lead is more toxic, which is reflected in the threshold limit values. The main potential hazard associated with depleted uranium is inhalation of the aerosols created when a projectile hits an armoured target. A person can be exposed to lead in similar ways. Accidental dangerous exposures can result from contact with both substances. Encountering uranium fragments is of minor significance because of the low penetration depth of alpha particles emitted by uranium: they are unable to penetrate even the superficial keratin layer of human skin. An additional cancer risk attributable to the uranium exposure might be significant only in case of prolonged contact of the contaminant with susceptible tissues. Lead intoxication can be observed in the wounded, in workers manufacturing munitions etc; moreover, lead has been documented to have a negative impact on the intellectual function of children at very low blood concentrations. It is concluded on the basis of the literature overview that replacement of lead by depleted uranium in munitions would be environmentally beneficial or largely insignificant because both lead and uranium are present in the environment. (opinion)

  10. Depleted uranium instead of lead in munitions: the lesser evil.

    Science.gov (United States)

    Jargin, Sergei V

    2014-03-01

    Uranium has many similarities to lead in its exposure mechanisms, metabolism and target organs. However, lead is more toxic, which is reflected in the threshold limit values. The main potential hazard associated with depleted uranium is inhalation of the aerosols created when a projectile hits an armoured target. A person can be exposed to lead in similar ways. Accidental dangerous exposures can result from contact with both substances. Encountering uranium fragments is of minor significance because of the low penetration depth of alpha particles emitted by uranium: they are unable to penetrate even the superficial keratin layer of human skin. An additional cancer risk attributable to the uranium exposure might be significant only in case of prolonged contact of the contaminant with susceptible tissues. Lead intoxication can be observed in the wounded, in workers manufacturing munitions etc; moreover, lead has been documented to have a negative impact on the intellectual function of children at very low blood concentrations. It is concluded on the basis of the literature overview that replacement of lead by depleted uranium in munitions would be environmentally beneficial or largely insignificant because both lead and uranium are present in the environment. PMID:24594921

  11. Health and environmental problems of using antiarmour munitions containing depleted uranium core

    International Nuclear Information System (INIS)

    In the 1970s, core of depleted uranium commenced to be introduced into the breakthrough antitank munitions of various calibers and types in order to considerably enhance their effectiveness due to extremely high density in comparison with steel. The health and environmental threats of using this munitions and other weaponry where depleted uranium has been utilised as counterbalance stem from the pyrophoric character of uranium, burnt due to material deformation and friction when penetrating armour targets creating thus highly respirable aerosol of uranium oxides that are deposited in alveoli after being inhaled or in other tissues after being ingested. Composition and main properties of depleted uranium are presented. Chronic effects of deposited particles of uranium oxides are due to internal irradiation of sensitive organs at proceeding radioactive decay accompanied with alpha irradiation. Long-term internal irradiation by radionuclides producing alpha-rays leads to proved risk of increased incidence of carcinoma and leukaemia not to speak on chronic chemical toxicity of uranium, independent of its isotopic composition. Environmental impact of extensive use of munitions with depleted uranium in the recent armed conflicts is assessed. (authors)

  12. [Cancer incidence in the military: an update].

    Science.gov (United States)

    Peragallo, Mario Stefano; Urbano, Francesco; Sarnicola, Giuseppe; Lista, Florigio; Vecchione, Alfredo

    2011-01-01

    An abnormally elevated rate of Hodgkin's lymphoma was reported in 2001 among Italian soldiers in Bosnia and Kosovo since 1995: a surveillance system was therefore set up for the military community. Preliminary results for a longer period (1996-2007) have shown incidence rates lower than expected for all malignancies. No significant difference was registered between observed and expected cases of Hodkin's lymphoma: the excess of reported cases for this malignancy in 2001-2002 was probably due to a peak occurred in 2000 among the whole military; it is therefore unrelated to deployment in the Balkans, and probably represents a chance event. Moreover, a significant excess of thyroid cancer was reported among the whole military.The estimated number of incident cases, including those missed by the surveillance system, was not significantly higher than expected for all cancers; conversely, the estimated incidence rate of thyroid cancer was significantly increased; this excess, however, is probably due to a selection bias.These data concerning cancer surveillance in the Italian military are consistent with lacking evidence of an increased cancer incidence among troops of other countries deployed in the areas of Iraq, Bosnia, and Kosovo, where armour penetrating depleted uranium shells have been used. However, a comprehensive assessment of cancer morbidity in the military requires a revision of the privacy regulations, in order to link individual records of military personnel and data bases of the National Health Service. PMID:22166781

  13. Recent developments in blast furnace process control within British Steel

    Energy Technology Data Exchange (ETDEWEB)

    Warren, P.W. [British Steel Technical, Middlesbrough (United Kingdom). Teesside Labs.

    1995-12-01

    British Steel generally operates seven blast furnaces on four integrated works. All furnaces have been equipped with comprehensive instrumentation and data logging computers over the past eight years. The four Scunthorpe furnaces practice coal injection up to 170 kg/tHM (340 lb/THM), the remainder injecting oil at up to 100 kg/tHM (200 lb/THM). Distribution control is effected by Paul Wurth Bell-Less Tops on six of the seven furnaces, and Movable Throat Armour with bells on the remaining one. All have at least one sub burden probe. The blast furnace operator has a vast quantity of data and signals to consider and evaluate when attempting to achieve the objective of providing a consistent supply of hot metal. Techniques have been, and are being, developed to assist the operator to interpret large numbers of signals. A simple operator guidance system has been developed to provide advice, based on current operating procedures and interpreted data. Further development will involve the use of a sophisticated Expert System software shell.

  14. Interaction of limestone grains and acidic solutions from the oxidation of pyrite tailings

    Energy Technology Data Exchange (ETDEWEB)

    Simon, M. [Departamento de Edafologia, EPS-CITE IIB, Canada San Urbano, Universidad de Almeria, 04120 Almeria (Spain)]. E-mail: msimon@ual.es; Martin, F. [Departamento de Edafologia, Facultad de Ciencias, Universidad de Granada, 18002 Granada (Spain); Garcia, I. [Departamento de Edafologia, EPS-CITE IIB, Canada San Urbano, Universidad de Almeria, 04120 Almeria (Spain); Bouza, P. [Centro Nacional Patagonico, CONICEF, Boulevard Brown s/n, 9120 Puerto Madryn, Chubut (Argentina); Dorronsoro, C. [Departamento de Edafologia, Facultad de Ciencias, Universidad de Granada, 18002 Granada (Spain); Aguilar, J. [Departamento de Edafologia, Facultad de Ciencias, Universidad de Granada, 18002 Granada (Spain)

    2005-05-01

    To characterise the coatings formed and to analyse element partitioning between the aqueous and solid phase, suspensions were prepared with four grain sizes of limestone and three different amounts of acidic solution from oxidized pyrite tailings. In all cases, red coatings with three different layers covered the grain surface, sealing off the acidic solution. The inner layer was composed mainly of basaluminite, the middle layer of schwertmannite, and the outer layer of gypsum and jarosite. Zn, Cd and Tl were co-precipitated by Fe and Al; As and Pb were co-precipitated almost completely by Fe; and Cu formed mainly Cu sulphates. All trace elements reached almost total precipitation at pH 6.3, but the precipitation of As and Pb tended to decrease as the pH rose. Consequently, liming should be calculated so that the soil pH does not exceed 6.3. This calculation should take into account that the armouring of the limestone grains can cause underestimations in the amount of liming material needed. - Basaluminite, schwertmannite and jarosite armored the limestone grains, and almost all trace elements co-precipitated, but the precipitation of As and Pb tended to decrease as the pH rose.

  15. Microjetting from grooved surfaces in metallic samples subjected to laser driven shocks

    International Nuclear Information System (INIS)

    When a shock wave propagating in a solid sample reflects from a free surface, geometrical effects predominantly governed by the roughness and defects of that surface may lead to the ejection of tiny jets that may breakup into high velocity, approximately micrometer-size fragments. This process referred to as microjetting is a major safety issue for engineering applications such as pyrotechnics or armour design. Thus, it has been widely studied both experimentally, under explosive and impact loading, and theoretically. In this paper, microjetting is investigated in the specific loading conditions associated to laser shocks: very short duration of pressure application, very high strain rates, small spatial scales. Material ejection from triangular grooves in the free surface of various metallic samples is studied by combining transverse optical shadowgraphy and time-resolved velocity measurements. The influences of the main parameters (groove angle, shock pressure, nature of the metal) on jet formation and ejection velocity are quantified, and the results are compared to theoretical estimates

  16. Non-dairy probiotic beverages: the next step into human health.

    Science.gov (United States)

    Gawkowski, D; Chikindas, M L

    2013-06-01

    Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit to the host. The two main genera of microorganisms indicated as sources of probiotic bacteria are Lactobacillus and Bifidobacterium. Historically used to produce fermented dairy products, certain strains of both genera are increasingly utilised to formulate other functional foods. As the consumers' understanding of the role of probiotics in health grows, so does the popularity of food containing them. The result of this phenomenon is an increase in the number of probiotic foods available for public consumption, including a rapidly-emerging variety of probiotic-containing non-dairy beverages, which provide a convenient way to improve and maintain health. However, the composition of non-dairy probiotic beverages can pose specific challenges to the survival of the health conferring microorganisms. To overcome these challenges, strain selection and protection techniques play an integral part in formulating a stable product. This review discusses non-dairy probiotic beverages, characteristics of an optimal beverage, and commonly used probiotic strains, including spore-forming bacteria. It also examines the most recent developments in probiotic encapsulation technology with focus on nano-fibre formation as a means of protecting viable cells. Utilising bacteria's natural armour or creating barrier mechanisms via encapsulation technology will fuel development of stable non-dairy probiotic beverages. PMID:23271064

  17. The banning of sportsmen and women who fail drug tests is unjustifiable.

    Science.gov (United States)

    Shuster, S; Devine, J W

    2013-01-01

    The use of performance enhancing drugs among elite athletes has been in the headlines recently, particularly with Lance Armstrong's fall from grace and his admission about widespread doping. Many argue that the use of drugs confers an unfair advantage and is ultimately dangerous to the health of the athletes. Others, like Professor Shuster, argue that the use of drugs is no different from other techniques employed by athletes to boost their performance: swimmers shaving their body hair; skiers wearing sleek body armour; archers and shooters having laser eye surgery to improve their accuracy. Professor Shuster puts forward the provocative argument that since 'there is no acceptable proof (that) drugs improve competitive performance and their use is no different from accepted sports practice, banning them is wrong and immoral.' JW Devine argues the other side, that the use of performance enhancing drugs poses a 'significant risk to the health of athletes' and perhaps more importantly, 'threatens to undermine the very purpose of sport' by disrupting the 'balance of excellences'. PMID:23516691

  18. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Directory of Open Access Journals (Sweden)

    Magier M.

    2012-08-01

    Full Text Available The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it’s particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot and tungsten alloy (penetrator are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ⋅ 104s−1 (for aluminium alloy and 6 ⋅ 103s−1 (for tungsten alloy.

  19. Metallographic characterisation of Al6061-T6 aluminium plates subjected to ballistic impact

    International Nuclear Information System (INIS)

    Al6061-T6 aluminium single layer plates, of different thickness, impacted by two different 7.62 mm Armour Piercing projectiles are studied from a metallographic point of view. The material behaviour after ballistic impact is investigated by optical and scanning electron microscopy as well as by micro-hardness tests. The study allows one to highlight the physical phenomena that happen during the impact: the formation of adiabatic shear bands (ASB), the evolution of softening and hardening phenomena, the creation of petalling, plugging and the formation of a melted film between the target and the penetrator as well as the localised failure mechanism. The thermo-mechanical effects on the target and the penetrator material have been examined in order to investigate in the physical phenomena ruling the ballistic damage; the differences between the two types of impactors are also highlighted. Among interesting findings, it has been noticed that a complete penetration is less detrimental and tungsten core projectile seems more damaging for the structural integrity of Al6061-T6 plates. A complete penetration allows the material to better dissipate the plastic deformation energy induced by bullet whereas the arrest increases localised material softening effect resulting in the formation of ASB. Although the creation of numerical models is not the aim of the present paper, the findings could be useful for the building of a modelling approach capable of replicating all the involved phenomena in details

  20. Anthropometric assessment of cervical neurovascular structures using CTA to determine zone-specific vulnerability to penetrating fragmentation injuries

    International Nuclear Information System (INIS)

    Aim: To determine military-specific cervical neurovascular and external anthropometric data to scale future numerical injury models of the neck and improve body armour design with a view to prevention or mitigation of combat neck injury. Materials and methods: Contrast-enhanced computed tomography (CT) angiograms of 50 UK servicemen were analysed. Mean diameters and distances from the skin surface were determined for the carotid artery (CA), internal jugular vein (IJV), vertebral artery (VA) and spinal cord (SC) at the three surgical neck zones. Horizontal neck circumference at C6 and three potential vertical cervical anthropometric measurements were analysed to determine which had the least variability between subjects. Results: The diameters of cervical vascular structures are greater and the vessels more superficial as the anatomical plane moves caudally. The SC and VA are better protected than the IJV and CA due to their greater depth and bony coverage, except for the VA in zone 1. Conclusion: Future cervical anthropometric assessments should use the vertical angle of mandible to mid-claviclular distance in combination with the horizontal neck circumference as these demonstrated the least variability. Cervical neurovascular structures are least vulnerable posterosuperiorly and therefore extending the posterior aspect of a ballistic helmet inferiorly or adding a nape protector would appear to be less justified. Cervical vessels are most vulnerable in zone 1 and a circumferential collar of ballistic material at least 75 mm high would cover this area in 95% of this population.

  1. Macroform and microform-induced change in redox-sensitive chemistries of river channel surface sediments

    Science.gov (United States)

    Byrne, P.; Zhang, H.; Heathwaite, A. L.; Binley, A.; Ullah, S.; Kaeser, D.; Heppell, C. M.; Lansdown, K.; Trimmer, M.

    2012-04-01

    In-stream geomorphological features such as riffle-pool sequences (macroforms) can produce steep hydraulic gradients which induce flow in and out of the riverbed - hyporheic exchange flow (HEF). The acceleration of flow over channel obstacles such as large cobbles and boulders (microforms) can create variation in surface-subsurface pressure gradients and generation of HEF. HEF in shallow surface sediments affect the transformation of redox-sensitive chemical forms and, therefore, the attenuation or release of nutrients in river systems. Here, we examine the relationship between stream geomorphological environment (microform and macroform) and concentration profiles of redox-sensitive species (nitrate, sulphate, iron, manganese) in shallow (15cm) subsurface sediments. In-situ passive samplers (diffusive equilibrium in thin films - DET) are used to obtain biogeochemical data from armoured environments at fine scale (cm) depth resolution where there is strong upwelling. The probes were deployed in a 50m reach of the River Eden, Cumbria, UK, during baseflow conditions. The experimental setup allowed for the assessment of differences in redox-sensitive chemistries between a riffle and pool environment and between smooth and rough bed surfaces in the pool. The passive sensing basis of the DET methodology provided a means for investigating how HEF systems generated at two different geomorphological scales influence the concentration and spatial patterns of redox-sensitive species. DET's capability of measuring at high spatial resolution allowed the extent of hyporheic mixing to be targeted, even though it is often limited to the top few centimetres of sediment.

  2. Effect of UV-B radiation on leaf optical properties measured with fibre optics

    International Nuclear Information System (INIS)

    Changes in the internal light microenvironment in leaves of plants of Brassica campestris L. cv. Emma, B. carinata L., and Medicago saliva L. cv. Armour in response to exposure to UV-B (UV-B, 280–320 nm) radiation were measured using a fibreoptic microprobe. Plants were exposed for 2 weeks either to high visible light or to supplemental ultraviolet-B radiation. The spectral regime (400–700 nm; PAR ) was measured either midway through the leaf palisade or the spongy mesophyll. After exposure to UV-B radiation leaves of Brassica campesiris attenuated transmitted light more than the controls. At the same time both forward and back scattered light increased in the palisade and spongy mesophylls. In contrast, UV-treatment of Medicago saliva leaves increased light transmission into the palisade, while the back scattered component showed little change. Leaves of cariiwla showed little change in response to UV. Other responses to UV-B radiation included increases in leaf thickness, decreased total chlorophyll content, and changes in UV-B screening pigments and chlorophyll fluorescence induction kinetics. Brassica campestris was most sensitive to exposure to enhanced levels of UV-B radiation, whereas leaves of B. carinata were the least sensitive. Our data indicate that exposure to UV-B radiation altered the light microenvironment within leaves of the species different ways. These changes appeared to be caused by alterations in pigment content and leaf anatomy. In turn, the altered distribution of PAR within the leaf could influence photosynthesis

  3. Measurements of near-ultimate strength for multiwalled carbon nanotubes and irradiation-induced crosslinking improvements.

    Energy Technology Data Exchange (ETDEWEB)

    Peng, B.; Locascio, M.; Zapol, P.; Li, S.; Mielke, S. L.; Schatz, G. C.; Espinosa, H. D.; Northwestern Univ.

    2008-01-01

    The excellent mechanical properties of carbon nanotubes are being exploited in a growing number of applications from ballistic armour to nanoelectronics. However, measurements of these properties have not achieved the values predicted by theory due to a combination of artifacts introduced during sample preparation and inadequate measurements. Here we report multiwalled carbon nanotubes with a mean fracture strength >100 GPa, which exceeds earlier observations by a factor of approximately three. These results are in excellent agreement with quantum-mechanical estimates for nanotubes containing only an occasional vacancy defect, and are {approx}80% of the values expected for defect-free tubes. This performance is made possible by omitting chemical treatments from the sample preparation process, thus avoiding the formation of defects. High-resolution imaging was used to directly determine the number of fractured shells and the chirality of the outer shell. Electron irradiation at 200 keV for 10, 100 and 1,800 s led to improvements in the maximum sustainable loads by factors of 2.4, 7.9 and 11.6 compared with non-irradiated samples of similar diameter. This effect is attributed to crosslinking between the shells. Computer simulations also illustrate the effects of various irradiation-induced crosslinking defects on load sharing between the shells.

  4. Measurements of near-ultimate strength for multiwalled carbon nanotubes and irradiation-induced crosslinking improvements

    International Nuclear Information System (INIS)

    The excellent mechanical properties of carbon nanotubes are being exploited in a growing number of applications from ballistic armour to nanoelectronics. However, measurements of these properties have not achieved the values predicted by theory due to a combination of artifacts introduced during sample preparation and inadequate measurements. Here we report multiwalled carbon nanotubes with a mean fracture strength >100 GPa, which exceeds earlier observations by a factor of approximately three. These results are in excellent agreement with quantum-mechanical estimates for nanotubes containing only an occasional vacancy defect, and are ∼80% of the values expected for defect-free tubes. This performance is made possible by omitting chemical treatments from the sample preparation process, thus avoiding the formation of defects. High-resolution imaging was used to directly determine the number of fractured shells and the chirality of the outer shell. Electron irradiation at 200 keV for 10, 100 and 1,800 s led to improvements in the maximum sustainable loads by factors of 2.4, 7.9 and 11.6 compared with non-irradiated samples of similar diameter. This effect is attributed to crosslinking between the shells. Computer simulations also illustrate the effects of various irradiation-induced crosslinking defects on load sharing between the shells.

  5. ITER in-vessel system design and performance

    International Nuclear Information System (INIS)

    This paper reviews the design and performance of the in-vessel components of ITER as developed for the EDA Final Design Report (FDR). The double-wall vessel is the first confinement boundary and is designed to maintain its integrity under all normal and off-normal conditions, e.g., the most intense VDE's and seismic events. The shielding blanket consists of modules connected to a toroidal backplate by flexible connectors which allow differential displacements due to temperature differences. Breeding blanket modules replace the shield modules for the Enhanced Performance Phase. The divertor is based on a cassette structure which is convenient for remote installation and removal. High heat flux (HHF) components are mechanically attached and can be removed and replaced in the hot cell. Operation of the divertor is based on achieving partially detached plasma conditions along and near the separatrix. Nominal heat loads of 5-10 MW/m2 are expected and these are accommodated by HHF technology developed during the EDA. Disruptions and VDE's can lead to melting of the first wall armour but no damage to the underlying structure. Stresses in the main structural components remain within allowables for all postulated disruption and seismic events. (author)

  6. The Dynamic Behaviour and Shock Recovery of a Porcine Skeletal Muscle Tissue

    Science.gov (United States)

    Wilgeroth, James; Hazell, Paul; Appleby-Thomas, Gareth

    2011-06-01

    Modern-day ballistic armours provide a high degree of protection to the individual. However, the effects of non-penetrating projectiles, blast, and high-energy blunt impact events may still cause severe tissue trauma/remote injury. The energies corresponding to such events allow for the formation and transmission of shock waves within body tissues. Consequently, the nature of trauma inflicted upon such soft tissues is likely to be intimately linked to their interaction with the shock waves that propagate through them. Notably, relatively little is known about the effect of shock upon the structure of biological materials, such as skeletal muscle tissue. In this study plate-impact experiments have been used to interrogate the dynamic response of a porcine skeletal muscle tissue under one-dimensional shock loading conditions. Additionally, development of a soft-capture system that has allowed recovery of shocked skeletal muscle tissue specimens is discussed and comparison made between experimental diagnostics and hydrocode simulations of the experiment.

  7. Nonlinear behavior of nuclear buildings made of low slenderness ratio under alternate loading. Vol. 1

    International Nuclear Information System (INIS)

    Outside horizontal forces shells of a nuclear building are subjected to traction or compression vertical forces on the horizontal cross section, they are indeed gravity forces (compression) or vertical component of seismic sollicitation (traction). These shells, generally twice more reinforced than ordinary buildings, have a slenderness ratio rarely above 1. Role of shearing stress is more important than flexion. As a result, horizontal reinforcements of low slenderness ratio loose their efficiency in shear resistance, however in some case local resistance to shear is secured. Flexure resistance is obtained by armouring in vertical edges. Resistance, ductility damping and rigidity of plane shells are studied under the action of repeated alternate horizontal forces with or without a perpendicular traction (or compression) force. A computer code CADBANU was realized to study the response of nuclear building made of low slenderness ratio under a dynamic excitation applied to the base. This program gives the horizontal translation and rotation for each floor. The first version of this program was verified and graphic results are given

  8. Optimisation of Kinematics for Tracked Vehicle Hydro Gas Suspension System

    Directory of Open Access Journals (Sweden)

    S. Sridhar

    2006-11-01

    Full Text Available The modern-day armoured fighting vehicles (AFVs are basically tracked vehicles equippedwith hydro gas suspensions, in lieu of conventional mechanical suspensions like torsion barand coil spring bogie suspensions. The uniqueness of hydro gas suspension is that it offersa nonlinear spring rate, which is very much required for the cross-country moveability of atracked vehicle. The AFVs have to negotiate different cross-country terrains like sandy, rocky,riverbed, etc. and the road irregularities provide enumerable problems during dynamic loadingsto the design of hydro gas suspension system. Optimising various design parameters demandsinnovative design methodologies to achieve better ride performance. Hence, a comprehensivekinematic analysis is needed. In this study, a methodology has been derived to optimise thekinematics of the suspension by reorienting the cylinder axis and optimising the loadtransferringleverage factor so that the side thrust on the cylinder is minimised to a greaterextent. The optimisation ultimately increases the life of the high-pressure and high-temperaturepiston seals, resulting in enhanced system life for better dependability.

  9. Mobile and stationary laser weapon demonstrators of Rheinmetall Waffe Munition

    Science.gov (United States)

    Ludewigt, K.; Riesbeck, Th.; Baumgärtel, Th.; Schmitz, J.; Graf, A.; Jung, M.

    2014-10-01

    For some years Rheinmetall Waffe Munition has successfully developed, realised and tested a variety of versatile high energy laser (HEL) weapon systems for air- and ground-defence scenarios like C-RAM, UXO clearing. By employing beam superimposition technology and a modular laser weapon concept, the total optical power has been successively increased. Stationary weapon platforms and now military mobile vehicles were equipped with high energy laser effectors. Our contribution summarises the most recent development stages of Rheinmetalls high energy laser weapon program. We present three different vehicle based HEL demonstrators: the 5 kW class Mobile HEL Effector Track V integrated in an M113 tank, the 20 kW class Mobile HEL Effector Wheel XX integrated in a multirole armoured vehicle GTK Boxer 8x8 and the 50 kW class Mobile HEL Effector Container L integrated in a reinforced container carried by an 8x8 truck. As a highlight, a stationary 30 kW Laser Weapon Demonstrator shows the capability to defeat saturated attacks of RAM targets and unmanned aerial vehicles. 2013 all HEL demonstrators were tested in a firing campaign at the Rheinmetall testing centre in Switzerland. Major results of these tests are presented.

  10. Depleted uranium (DU) mobility in the natural environment

    International Nuclear Information System (INIS)

    In 1999 the Balkan's conflict lead NATO war planes to leave 10x103 kg of depleted uranium (DU) in the environment of Kosovo and neighbouring states (UNEP, 2001). DU behaves in the same manner in the environment as natural uranium and it can be traced with isotopic analysis due to the fact that DU has the isotopic composition of 0.2% 235 U and 99.8% 238 U as opposed to natural uranium which has 0.7% 235 U and 99.3% 238 U. DU is a waste product of the nuclear industry which enrich nuclear fuel by 235 U. Large stock piles of DU therefore exist in countries that produce nuclear energy and/or nuclear weapons. The DU is given to the weapons industry for free (or cheap) and has been a popular choice for armour penetrating arsenal due to the high density of uranium (19 g cm-3 ) and therefore its high penetrating power. Indeed the arsenal used in Kosovo consisted of DU penetrators that were shot from A-10 aeroplanes. They weigh roughly 300 g and have the shape of a fat 9 cm long pencil. (author)

  11. A new pupillarial scale insect (Hemiptera: Coccoidea: Eriococcidae) from Angophora in coastal New South Wales, Australia.

    Science.gov (United States)

    Gullan, Penny J; Williams, Douglas J

    2016-01-01

    A new scale insect, Aolacoccus angophorae gen. nov. and sp. nov. (Eriococcidae), is described from the bark of Angophora (Myrtaceae) growing in the Sydney area of New South Wales, Australia. These insects do not produce honeydew, are not ant-tended and probably feed on cortical parenchyma. The adult female is pupillarial as it is retained within the cuticle of the penultimate (second) instar. The crawlers (mobile first-instar nymphs) emerge via a flap or operculum at the posterior end of the abdomen of the second-instar exuviae. The adult and second-instar females, second-instar male and first-instar nymph, as well as salient features of the apterous adult male, are described and illustrated. The adult female of this new taxon has some morphological similarities to females of the non-pupillarial palm scale Phoenicococcus marlatti Cockerell (Phoenicococcidae), the pupillarial palm scales (Halimococcidae) and some pupillarial genera of armoured scales (Diaspididae), but is related to other Australian Myrtaceae-feeding eriococcids. PMID:27395159

  12. Diverter structure

    International Nuclear Information System (INIS)

    The present invention concerns a vacuum vessel for a tokamak-type nuclear fusion plasma experimental device, and provides a divertor structure capable of reducing a distance of a plasma facing surface of a divertor structure and an inner wall of the vacuum vessel while maintaining cooling and heat removing performance. Namely, in the divertor structure of the present invention, a compulsory cooling channel on the side receiving high temperature load is made of a highly heat conductive material such as copper. The compulsory cooling channel on the side secured to a substrate is made of a material having high mechanical strength, for example, stainless steel. With such a constitution, the compulsory cooling channel on the side receiving high temperature load transfers the heat received by an armour material from plasmas efficiently to coolants. The opposite side can be secured to the inner wall of the vacuum vessel with satisfactory mechanical strength without interposing other additional materials. As a result, the structure of the present invention can reduce the distance of the plasma facing surface of the divertor structure and the inner wall of the vacuum vessel while maintaining the cooling and heat removing performance. (I.S.)

  13. Irradiation effects on C/C composite materials for high temperature nuclear applications

    International Nuclear Information System (INIS)

    Excellent characteristics such as high strength and high thermal shock resistance of C/C composite materials have led us to try to apply them to the high temperature components in nuclear facilities. Such components include the armour tile of the first wall and divertor of fusion reactor and the elements of control rod for the use in HTGR. One of the most important aspects to be clarified about C/C composites for nuclear applications is the effect of neutron irradiation on their properties. At the Japan Atomic Energy Research Institute (JAERI), research on the irradiation effects on various properties of C/C composite materials has been carried out using fission reactors (JRR-3, JMTR), accelerators (TANDEM, TIARA) and the Fusion Neutronics Source (FNS). Additionally, strength tests of some neutron-irradiated elements for the control rod were carried out to investigate the feasibility of C/C composites. The paper summarises the R and D activities on the irradiation effects on C/C composites. (authors)

  14. Early results of studies on the levels of depleted uranium excreted by Balkan residents

    International Nuclear Information System (INIS)

    Urine samples collected from residents of Bosnia and Herzegovina and Kosovo were analysed to determine their natural and depleted uranium content using MC-ICP-MS. All may have been exposed to depleted uranium released as a consequence of the deployment of armour-piercing rounds by the US Air Force. A 236U tracer was employed to determine chemical recovery. Early results suggest that the levels of natural and depleted uranium excretion by the subjects, which ranged in age from 1 to 71 years, ranged from 2.8 - 58.2 ng d-1 and 1.3 - 46.3 ng d-1 , respectively. The results suggest accumulated body burdens of depleted uranium ranging from close to zero to 46 μg. All the body burdens predicted are lower than published values for the uranium content of the body (90μg) and health effects are not predicted. Further studies are underway to check the provenance of the results. (author)

  15. Quality control of FWC during assembly/commissioning on SST-1

    International Nuclear Information System (INIS)

    First Wall components (FWC) of SST-1 tokamak, which are in the immediate vicinity of plasma comprises of limiters, divertors, baffles, passive stabilizers are designed to operate long duration (1000 s) discharges of elongated plasma. All FWC consists of a copper alloy heat sink modules with SS cooling tubes brazed onto it, graphite tiles acting as armour material facing the plasma, and are mounted to the vacuum vessels with suitable Inconel support structures at ring and port locations. The FWC are very recently assembled and commissioned successfully inside the vacuum vessel of SST-1 under going a rigorous quality control and checks at every stage of the assembly process. This paper will present the quality control and checks of FWC from commencement of assembly procedure, namely material test reports, leak testing of high temperature baked components, assembled dimensional tolerances, leak testing of all welded joints, graphite tile tightening torques, electrical continuity of passive stabilizers, and electrical isolation of passive stabilizers from vacuum vessel, baking and cooling hydraulic connections inside vacuum vessel. (author)

  16. Assembly and metrology of first wall components of SST-1

    International Nuclear Information System (INIS)

    First Wall components (FWC) of SST-1 tokamak, which are in the immediate vicinity of plasma comprises of limiters, divertors, baffles, passive stabilizers are designed to operate long duration (1000 s) discharges of elongated plasma. All FWC consists of a copper alloy heat sink modules with SS cooling tubes brazed onto it, graphite tiles acting as armour material facing the plasma, and are mounted to the vacuum vessels with suitable Inconel support structures at ring and port locations. The FWC are very recently assembled and commissioned successfully inside the vacuum vessel of SST-1 under going a meticulous planning of assembly sequence, quality checks at every stage of the assembly process. This paper will present the metrology aspects and procedure of each FWC, both outside the vacuum vessel, and inside the vessel, assembly tolerances, tools, equipment and jig/fixtures, used at each stage of assembly, starting from location of support bases on vessel rings, fixing of copper modules on support structures, around 3800 graphite tile mounting on 136 copper modules with proper tightening torques, till final toroidal and poloidal geometry of the in-vessel components are obtained within acceptable limits, also ensuring electrical continuity of passive stabilizers to form a closed saddle loop, electrical isolation of passive stabilizers from vacuum vessel. (author)

  17. Investigation of Be/Cu joints via HHF tests of small-scale mockups

    Energy Technology Data Exchange (ETDEWEB)

    Giniatulin, R.; Gervash, A.; Komarov, V.L.; Litunovsky, N.; Mazul, I.; Yablokov, N. [Efremov Inst., St. Petersburg (Russian Federation)

    1998-01-01

    Beryllium-copper (Be/Cu) joints in divertor components work under cyclic heat loads. To develop reliable joints small-scale mockups are fabricated by divertor technologies and tested under the divertor conditions. One of the critical damaging factors that exist in the divertor and have to be simulated is thermocyclic heat loads in the range of 1-15 MW/m{sup 2}. This work presents the divertor mockups that have beryllium tiles with different dimensions (5 x 5 - 44 x 44) mm{sup 2} brazed with copper alloy heat sink. The electron beam was used to braze these mockups so as to decrease the formation of brittle intermetallic layers. The description of mockups design, geometry of armour tiles and fabrication techniques are presented in the paper. The results of screening and thermocyclic tests of these mockups in the heat flux range of 2-12 MW/m{sup 2} with a number of cycles {approx}10{sup 3} are presented. The results of metallographic analysis are also presented. The results of fabrication and testing with small-scale mockups for first wall application are also described. (author)

  18. Increased noise levels have different impacts on the anti-predator behaviour of two sympatric fish species.

    Directory of Open Access Journals (Sweden)

    Irene K Voellmy

    Full Text Available Animals must avoid predation to survive and reproduce, and there is increasing evidence that man-made (anthropogenic factors can influence predator-prey relationships. Anthropogenic noise has been shown to have a variety of effects on many species, but work investigating the impact on anti-predator behaviour is rare. In this laboratory study, we examined how additional noise (playback of field recordings of a ship passing through a harbour, compared with control conditions (playback of recordings from the same harbours without ship noise, affected responses to a visual predatory stimulus. We compared the anti-predator behaviour of two sympatric fish species, the three-spined stickleback (Gasterosteus aculeatus and the European minnow (Phoxinus phoxinus, which share similar feeding and predator ecologies, but differ in their body armour. Effects of additional-noise playbacks differed between species: sticklebacks responded significantly more quickly to the visual predatory stimulus during additional-noise playbacks than during control conditions, while minnows exhibited no significant change in their response latency. Our results suggest that elevated noise levels have the potential to affect anti-predator behaviour of different species in different ways. Future field-based experiments are needed to confirm whether this effect and the interspecific difference exist in relation to real-world noise sources, and to determine survival and population consequences.

  19. Development of a new version of the Vehicle Protection Factor Code (VPF3)

    Science.gov (United States)

    Jamieson, Terrance J.

    1990-10-01

    The Vehicle Protection Factor (VPF) Code is an engineering tool for estimating radiation protection afforded by armoured vehicles and other structures exposed to neutron and gamma ray radiation from fission, thermonuclear, and fusion sources. A number of suggestions for modifications have been offered by users of early versions of the code. These include: implementing some of the more advanced features of the air transport rating code, ATR5, used to perform the air over ground radiation transport analyses; allowing the ability to study specific vehicle orientations within the free field; implementing an adjoint transport scheme to reduce the number of transport runs required; investigating the possibility of accelerating the transport scheme; and upgrading the computer automated design (CAD) package used by VPF. The generation of radiation free field fluences for infinite air geometries as required for aircraft analysis can be accomplished by using ATR with the air over ground correction factors disabled. Analysis of the effects of fallout bearing debris clouds on aircraft will require additional modelling of VPF.

  20. The Logistics Of The War In The Sahel

    Directory of Open Access Journals (Sweden)

    Gary K Busch

    2013-06-01

    Full Text Available There are both positive and negative aspects of waging a counter-insurgency war in the Sahel. The impediments are easy to see. The terrain of the Sahel does not lend itself to conventional warfare. There are broad expanses of sand and dunes, broken up by small villages and, occasionally, a town or city. There are no petrol stations, wells, repair shops, water stores, food stocks or fuel reserves in most of the region. Trucks and buses, as well as conventional armour, are difficult to transport in such a terrain. Air bases are usually suited only to small aircraft and lack the fuel and equipment which allow the free flow of cargo. African insurgents are bands and groups of often, irregular soldiers. On the positive side, the lack of ground cover and a tree canopy in the region enables a strategy of using the most modern weapons, the Unmanned Aerial Vehicles (UAV which can seek out, observe and destroy small and mobile enemy forces. This has meant that the logistic demands of the war in the Sahel has generated a strategy of high-tech weaponry deployed by Western forces combined with African troops on the ground as garrison forces for towns and cities.

  1. Evaluation of PAH depletion of subsurface Exxon Valdez oil residues remaining in Prince William Sound in 2007-2008 and their likely bioremediation potential

    International Nuclear Information System (INIS)

    This study examined the extent of oil weathering at the Exxon Valdez oil spill (EVOS) sites and estimated the bioremediation potential for shoreline segments by examining the depletion of total polycyclic aromatic hydrocarbons (PAHs) relative to an estimated applicability threshold of 70 per cent. The distribution of oil was examined by location and current ratios of nitrogen and non-polar oil in order to assess if biodegradation rates were nutrient-limited. The impact of sequestration on the effectiveness of bioremediation was also studied. Results of the study showed that the EVOS residues are patchy and infrequently found on sites that were heavily oiled in 1989. Only 0.4 per cent of the oil originally stranded in 1989 remained. The remaining EVOS residues are sequestered under boulder and cobble armour in areas with limited contact with flowing water. The study also showed that concentrations of nitrogen and dissolved oxygen in pore waters within strata adjacent to the sequestered oil can support biodegradation. Most remaining EVOS residues are highly weathered and biodegraded. It was concluded that nutrients added to the shorelines are unlikely to effectively contact the sequestered oil. 31 refs., 2 tabs., 14 figs

  2. Evaluation of PAH depletion of subsurface Exxon Valdez oil residues remaining in Prince William Sound in 2007-2008 and their likely bioremediation potential

    Energy Technology Data Exchange (ETDEWEB)

    Atlas, R. [Louisville Univ., Louisville, KY (United States); Bragg, J.R. [Creative Petroleum Solutions LLC, Houston, TX (United States)

    2009-07-01

    This study examined the extent of oil weathering at the Exxon Valdez oil spill (EVOS) sites and estimated the bioremediation potential for shoreline segments by examining the depletion of total polycyclic aromatic hydrocarbons (PAHs) relative to an estimated applicability threshold of 70 per cent. The distribution of oil was examined by location and current ratios of nitrogen and non-polar oil in order to assess if biodegradation rates were nutrient-limited. The impact of sequestration on the effectiveness of bioremediation was also studied. Results of the study showed that the EVOS residues are patchy and infrequently found on sites that were heavily oiled in 1989. Only 0.4 per cent of the oil originally stranded in 1989 remained. The remaining EVOS residues are sequestered under boulder and cobble armour in areas with limited contact with flowing water. The study also showed that concentrations of nitrogen and dissolved oxygen in pore waters within strata adjacent to the sequestered oil can support biodegradation. Most remaining EVOS residues are highly weathered and biodegraded. It was concluded that nutrients added to the shorelines are unlikely to effectively contact the sequestered oil. 31 refs., 2 tabs., 14 figs.

  3. Ancient and historic steel in Japan, India and Europe, a non-invasive comparative study using thermal neutron diffraction.

    Science.gov (United States)

    Grazzi, F; Civita, F; Williams, A; Scherillo, A; Barzagli, E; Bartoli, L; Edge, D; Zoppi, M

    2011-05-01

    The production and refinement of steel has followed very different paths in different parts of the Eurasian continent. In aiming to characterize the similarities and differences between various smelting and smithing methods, we have analysed steel samples from four different areas and historic periods: the Kotō Age in Japan (twelfth-sixteenth century), the Moghul Empire in India (seventeenth-nineteenth century), the Ottoman Turkish Empire (seventeenth century) and the late Middle Ages (fifteenth century) in Italy. The best quality steel was employed for forging arms and armour of high quality, so that we have selected samples from Japan, India, the Middle East and Italy belonging to such a category. Traditional methods, such as metallography, used to characterize different steels in terms of their carbon contents, microconstituents and slag inclusions, entailed an invasive approach. Since many of the selected artefacts are in a very good state of conservation, a different and non-invasive approach was desirable. To this aim, we have used time of flight neutron diffraction on the Italian Neutron Experimental Station diffractometer, located at the pulsed neutron source ISIS in the United Kingdom. By this technique, we were able to quantify the phase distribution of the metal phases, the slag inclusion content, and the oxidation state of the samples, both as average concentration on the whole artefact and in selected gauge volumes. The results of the present investigation offer an interesting picture of the steel metallurgy in different areas of the world. PMID:21400072

  4. The WEST project: Current status of the ITER-like tungsten divertor

    International Nuclear Information System (INIS)

    Highlights: • We presented the ITER-like W components occurred for the WEST divertor. • The main features including key elements of the design were detailed. • The main results of studies investigating the integration constraints or issues were reported. • The WEST ITER-like divertor design reached a mature stage to enable the launching of the procurement phase. - Abstract: The WEST (W – for tungsten – Environment in Steady-state Tokamak) project is an upgrade of Tore Supra from a limiter based tokamak with carbon PFCs into an X-point divertor tokamak with full-tungsten armour while keeping its long discharge capability. The WEST project will primarily offer the key capability of testing for the first time the ITER technology in real plasma environment. In particular, the main divertor (i.e. the lower divertor) of the WEST project will be based on actively cooled tungsten monoblock components and will follow as closely as possible the design and the assembling technology, foreseen for the ITER divertor units. The current design of WEST ITER-like tungsten divertor has now reached a mature stage following the 2013 WEST Final Design Review. This paper presents the key elements of the design, reports the technological requirements and reviews the main design and integration issues

  5. Advanced technologies: Trends and implications for security

    International Nuclear Information System (INIS)

    As the world moves towards the close of the twentieth century, three technological trends will strongly influence security. In order of importance they are: first, the increasing globalization of the ability to develop and use high technology, much of which has both civilian and military applications; secondly, the broad dissemination of militarily-relevant technology world-wide; and thirdly, the continued development by the United States and the USSR (and a few other nations) of advanced technology for military applications. The military balance between the super-Powers and their allies has been strongly rooted in advancing military technology. Great changes in technology have resulted in adjustments -mostly in limited aspects such as the armour/ anti-armour balance - but have not caused it to change wildly. This seems likely to remain the case for the foreseeable future. There are arguments that Western technology has been a prime causative factor behind Soviet willingness to engage in negotiations to reduce forces. They claim that fear of the Strategic Defense Initiative is behind progress in the Strategic Arms Reduction Talks, and that perceived Western mastery of the technology for systems combining quick reaction, deep strike and high kill probabilities led the Soviet Union to reassess its potential for a successful land campaign in Europe. If current arms control negotiations are successful, the momentum is maintained, and other political changes take hold, the military balance could be taken to a point where ft would not be very sensitive to technological change. One should be aware that the arms control negotiations are very complex, primarily because of technological issues, and we should not yet bank on it all working out well. If it fails, the military technical competition will heat up again. Even under a strict arms control regime we can expect the competition to continue as each side seeks to develop counters to what ft sees as the other side

  6. Material Challenges For Plasma Facing Components in Future Fusion Reactors

    International Nuclear Information System (INIS)

    Increasing attention is directed towards thermonuclear fusion as a possible future energy source. Major advantages of this energy conversion technology are the almost inexhaustible resources and the option to produce energy without CO2-emissions. However, in the most advanced field of magnetic plasma confinement a number of technological challenges have to be met. In particular high-temperature resistant and plasma compatible materials have to be developed and qualified which are able to withstand the extreme environments in a commercial thermonuclear power reactor. The plasma facing materials (PFMs) and components (PFCs) in such fusion devices, i.e. the first wall (FW), the limiters and the divertor, are strongly affected by the plasma wall interaction processes and the applied intense thermal loads during plasma operation. On the one hand, these mechanisms have a strong influence on the plasma performance; on the other hand, they have major impact on the lifetime of the plasma facing armour. In present-day and next step devices the resulting thermal steady state heat loads to the first wall remain below 1 MWm-2; the limiters and the divertor are expected to be exposed to power densities being at least one order of magnitude above the FW-level, i.e. up to 20 MWm-2 for next step tokamaks such as ITER or DEMO. These requirements are responsible for high demands on the selection of qualified PFMs and heat sink materials as well as reliable fabrication processes for actively cooled plasma facing components. The technical solutions which are considered today are mainly based on the PFMs beryllium, carbon or tungsten joined to copper alloys or stainless steel heat sinks. In addition to the above mentioned quasi-stationary heat loads, short transient thermal pulses with deposited energy densities up to several tens of MJm-2 are a serious concern for next step tokamak devices. The most frequent events are so-called Edge Localized Modes (type I ELMs) and plasma disruptions

  7. Chromium-rich lawsonite in high-Cr eclogites from the Făgăras Massif (South Carpathians)

    Science.gov (United States)

    Negulescu, E.; Săbău, G.

    2012-12-01

    Lawsonite is a relatively rare phase in natural rocks, because of its thermal decomposition during exhumation, and Cr-bearing lawsonite being restricted to only a few occurrences worldwide. Here we report Cr-lawsonite in eclogites hosted in a medium-grade metamorphic complex. Several high-Cr eclogite lenses occur in the Topolog Complex (Făgăras Massif) of dominantly gneissic-amphibolitic composition. High Cr contents are the result of emerald-green mm-sized nodules containing Cr-rich minerals, embedded in a gray-green matrix of kyanite, clinopyroxene, garnet, amphibole, zoisite, and rutile. Garnets occur as porphyroblasts or in coronas around clinopyroxene aggregates probably replacing former magmatic pyroxene. Relict gabbroic textures (sometimes pegmatoid) and whole rock geochemistry indicate a gabbroic cumulate origin. The REE pattern, displaying a slight positive Eu anomaly and a tea spoon-shaped LREE depletion is also indicative of a cumulate origin, as also noted by Pe Piper & Piper (2002) for the Othrys gabbro (as well as others in the Vourinos and Pindos ophiolitic suites) with the same unusual REE-pattern. The emerald-green Cr-rich nodules are unevenly distributed in the rock, and always enclosed in Cr-rich clinopyroxenes (up to 5.46% Cr2O3) which may exhibit Cr-diffusion haloes towards normal Cr-free matrix pyroxene. The nodules consist of diablastic chromite, rutile and Cr-rich kyanite of up to 15.67 wt% Cr2O3, Cr-bearing epidote, to which Cr-rich staurolite (up to 10.45% Cr2O3; XMg up to 0.68) and Cr-rich lawsonite (up to 9.17% Cr2O3) may exceptionally associate. Cr concentrations in kyanite and lawsonite are, to our knowledge, the highest reported so far. Cr-lawsonite was identified in a single sample, as small single phase inclusions armoured in Cr-kyanite. Equilibrium PT-conditions of 2.6 GPa and 610o C were derived from the garnet-mantled clinopyroxene aggregates using multi-equilibria calculation with the PTGIBBS routine of Brandelik & Massonne

  8. Fine Sediment Residency in Streambeds in Southeastern Australia.

    Science.gov (United States)

    Croke, J. C.; Thompson, C. J.; Rhodes, E.

    2007-12-01

    A detailed understanding of channel forming and maintenance processes in streams requires some measurement and/or prediction of bed load transport and sediment mobility. Traditional field based measurements of such processes are often problematic due to the high discharge characteristics of upland streams. In part to compensate for such difficulties, empirical flow competence equations have also been developed to predict armour or bedform stabilising grain mobility. These equations have been applied to individual reaches to predict the entrainment of a threshold grain size and the vertical extent of flushing. In cobble- and boulder-bed channels the threshold grain size relates to the size of the bedform stabilising grains (eg. D84, D90). This then allows some prediction of when transport of the matrix material occurs. The application of Optically Stimulated Luminescence (OSL) dating is considered here as an alternative and innovative way to determine fine sediment residency times in stream beds. Age estimates derived from the technique are used to assist in calibrating sediment entrainment models to specific channel types and hydrological regimes. The results from a one-dimensional HEC-RAS model indicate that recurrence interval floods exceeding bankfull up to 13 years are competent to mobilise the maximum overlying surface grain sizes at the sites. OSL minimum age model results of well bleached quartz in the fine matrix particles are in general agreement with selected competence equation predictions. The apparent long (100-1400y) burial age of most of the mineral quartz suggests that competent flows are not able to flush all subsurface fine-bed material. Maximum bed load exchange (flushing) depth was limited to twice the depth of the overlying D90 grain size. Application of OSL in this study provides important insight into the nature of matrix material storage and flushing in mountain streams.

  9. The health hazards of depleted uranium munitions. Part 1

    International Nuclear Information System (INIS)

    There has been a substantial amount of public discussion on the health effects of the use of depleted uranium (DU), especially on the battlefield. The RoyaI Society therefore convened an independent expert Working Group to review the present state of scientific knowledge about the health and environmental effects of DU, in order to inform public debate. This is the first of two reports. It deals with the amounts of DU to which soldiers could be exposed on the battlefield, the risks from radiation, and what we know from epidemiological studies. We consider past and potential future exposures, the most likely exposures and the 'worst-case' exposures that cannot be excluded. Our second report, to be published later this year, will address the risks from toxic poisoning and environmental issues including risks to civilian populations. The group has consulted widely. It has focused on what is known scientifically about aspects that are relevant to health and has not considered the merits of using DU in munitions. Nor does this report analyse Gulf War syndrome, which has been the subject of other reports. DU is a toxic and weakly radioactive heavy metal that may have adverse consequences to human health, particularly if it enters the body through inhalation, ingestion or wounding. On the battlefield it is used in kinetic energy weapons designed to penetrate the armour of tanks and other vehicles. On impact substantial amounts of DU may be dispersed as particles that can be inhaled and as shrapnel. Our approach has been to estimate the typical levels of exposure on the battlefield over a wide range of scenarios, and the worst-case exposures that individuals are unlikely to exceed. From these we calculate the potential health risks from radiation. We have also considered epidemiological studies of occupational exposures to uranium in other situations as an independent source of information on the risks of inhaling DU particles, although we recognise that the parallels may

  10. Toxicity Determination of 8 Fungicides against Brown Spot of Yacon in Laboratory%8种杀菌剂对雪莲果褐斑病的室内毒力测定

    Institute of Scientific and Technical Information of China (English)

    姚昕; 涂勇

    2014-01-01

    8种杀菌剂对雪莲果褐斑病的室内毒力测定结果表明:供试药剂毒力由高到低依次为325g/L苯甲·嘧菌酯悬浮剂、10%苯醚甲环锉水分散粒剂、206.7g/L噁酮·氟硅唑乳油、125g/L氟环唑悬浮剂、250g/L吡唑嘧菌酯乳油、60%唑醚·代森联水分散粒剂、50%醚菌酯水分散粒剂和46%氢氧化铜水分散粒剂。以325g/L苯甲·嘧菌酯悬浮剂的抑制作用最好,其EC50为0.28mg/L。%Fungal toxicity testing indicated that the inhibition of eight kinds of fungicides against brown spot of yacon were very different and their toxicity from high to low were followed by 325g/L benzoic,azoxystrobin, 10%difenoconazole file, 206.7g/Ldioxanone flusilazole, 125g/L epoxiconazole, 250g/L pyrazole azoxystrobin, 60% ether metiram, 50% water kresoxim and 46% cupric hydroxide respectively,and 325g/L Benzene armour was the best inhibition. Its EC50 was only 0.28mg/L.

  11. Wear resistance of thick diamond like carbon coatings against polymeric materials used in single screw plasticizing technology

    Science.gov (United States)

    Zitzenbacher, G.; Liu, K.; Forsich, C.; Heim, D.

    2015-05-01

    Wear on the screw and barrel surface accompany polymer single screw plasticizing technology from the beginning. In general, wear on screws can be reduced by using nitrided steel surfaces, fused armour alloys on the screw flights and coatings. However, DLC-coatings (Diamond Like Carbon) comprise a number of interesting properties such as a high hardness, a low coefficient of friction and an excellent corrosion resistance due to their amorphous structure. The wear resistance of about 50 µm thick DLC-coatings against polyamide 6.6, polybutylene terephthalate and polypropylene is investigated in this paper. The tribology in the solids conveying zone of a single screw extruder until the beginning of melting is evaluated using a pin on disc tribometer and a so called screw tribometer. The polymeric pins are pressed against coated metal samples using the pin on disc tribometer and the tests are carried out at a defined normal force and sliding velocity. The screw tribometer is used to perform tribological experiments between polymer pellets and rotating coated metal shafts simulating the extruder screw. Long term experiments were performed to evaluate the wear resistance of the DLC-coating. A reduction of the coefficient of friction can be observed after a frictional distance of about 20 kilometers using glass fibre reinforced polymeric materials. This reduction is independent on the polymer and accompanied by a black layer on the wear surface of the polymeric pins. The DLC-coated metal samples show an up to 16 µm deep wear track after the 100 kilometer test period against the glass fiber filled materials only.

  12. Investigation of some cleaning surface treatments for the fabrication of ITER first wall panels by HIP

    International Nuclear Information System (INIS)

    Full text of publication follows: ITER First Wall (FW) panels are the innermost part of the ITER reactor. Metallic materials used for their manufacture are 316L(N)-IG stainless steel, a copper alloy and beryllium. Stainless steel material is a support structure for the copper alloy that serves as a heat sink material and also for the beryllium tiles that are a protective armour against the plasma. All these materials are bonded together by Hot Isostatic Pressing (HIP). Thus, several types of joints (Cu/Cu, Cu/SS, SS/SS or Cu/Be) are present in a FW panels. Their manufacturing requires a very strict and advanced metallic surface preparation in order to eliminate most of the organic or oxide layers that could prevent the diffusion process between the facing materials. In this field, our laboratory practice enables to obtain sufficiently clean metallic surfaces and high strength joints are obtained when small mockups are made. However, the manufacture of a large number of FW panels in the future requires to find a new cleaning process that is industrially relevant without a strong reduction of the joint's mechanical properties. In this paper we present our investigations to find an industrial solution to clean efficiently copper alloy and stainless steel materials in order to manufacture high strength Cu/Cu, SS/SS or Cu/SS joints. Products investigated are mainly acid liquids proposed by chemical Company and a more advanced technique that uses a plasma process. HIP joints are tested mechanically by making impact toughness and tensile measurements. Results obtained with these solutions are compared to those obtained in our Laboratory by using our own cleaning route. Moreover, XPS analyses are performed on small specimens that have been submitted to the same cleaning treatments in order to better understand the mechanical results of our specimens. (authors)

  13. A simple in-vessel/FW component viewing system for SST-1

    International Nuclear Information System (INIS)

    A simple compact system is being proposed for in-situ visual inspection of around 3800 First Wall (FW) graphite (armour) tiles in the vacuum vessel of SST-1 tokamak. The 2 DOF, manual driven system (permanently stationed inside vacuum vessel behind outer passive stabilizer) at top and bottom mid-plane locations consist of a rack and pinion mechanism operating a arm with a CCD camera/LED mounted on it, moving over a cam profile to cover approximately 1/8th of the toroidal span of the vacuum vessel both at interior top/bottom locations with in the FW modules. The camera and LED light should withstand the ultrahigh vacuum conditions, prolonged baking temperatures of around 200°C along with high electromagnetic forces inside the vessel. This system can be operated remotely in-between shots from outside the VV through a linear motion feed through providing linear moment to a rack and pinion mechanism connected to the arm. This mechanism provides a better viewing of the inside FW components and vessel wall surface of tokamak with simple engineering and operational effort. Any information can be acquired from system regarding damages to FWC due to interaction with plasma as well as damage of other support structures inside VV. In comparison to more complicated and complex inspection system used in other tokamaks, this mechanism can be used for frequent in vessel visual inspection, which limits the system to be small, simple, occupying less space and custom made. This system is cheap with a minimum time for realization of the concept. The paper will present the conceptual and engineering design aspect of the in-viewing system, CAD images, its advantages and limitations, camera and LED details, data acquisition and the present status of realization of the project. (author)

  14. Development of radiation shielding materials and NBC pads for infantry combat vehicle and tank

    International Nuclear Information System (INIS)

    Tanks have special lining materials inside, providing a certain degree of radiation protection for operation in nuclear scenario's. At present these special lining materials in the form of sheets are imported and are fitted into armoured vehicles. Three types of polymer compositions; PE(M)SE, PEC-ISE and PEC-IISE were formulated based on polymer matrix, specific fillers and anti-ageing additives. Prototype NBC pads based on polymer composition PEC-ISE was finalized for moulding of NBC pads for use in ICVs and composition PE(M)SE was finalized for T-90 tanks. The physico-mechanical properties for NBC pads have been evaluated. Radiography of test samples was conducted to ensure homogeneity of specific fillers in the polymer matrix. Radiation shielding factors against nuclear radiation sources (60Co, I37Cs and 252Cf) were evaluated at DL Jodhpur and found to be better than imported Russian Pads designed for ICVs and T-90 Tanks. Drawings for twelve types of NBC pads for ICVs and one hundred eighteen types of pads for T-90 tank were generated with the help of design tool, Auto Desk Inventor-II and metallic moulds for moulding of NBC pads were fabricated. Prototype NBC pads were moulded through compression moulding process. Radiation protection factors of prototype NBC pads, after fitment in ICVs, were also evaluated against neutron and gamma (primary and secondary) radiation sources. Prototype NBC pads for ICVs have shown 20% improvement in overall protection level and NBC pads for T-90 tanks have been developed as per design requirements. Manufacturing facility for NBC shielding pads have been established in association with industries. (author)

  15. Disentangled solid state and metastable polymer melt; a solvent free route to high-modulus high-strength tapes and films of UHMWPE

    Science.gov (United States)

    Rastogi, Sanjay

    2013-03-01

    Ultra High Molecular Weight Polyethylene (UHMWPE) having average molar mass greater than a million g/mol is an engineering polymer. Due to its light-weight, high abrasion resistance and biocompatibility it is used for demanding applications such as body armour, prostheses etc. At present, because of its high melt viscosity to achieve the uniaxial/biaxial properties in the form of fibers/films the polymer is processed via solution route where nearly 95wt% of the solvent is used to process 5wt% of the polymer. In past several attempts have been made to process the polymer without using any solvent. However, compared to the solvent processing route the achieved mechanical properties were rather poor. Here we show that by controlled synthesis it is feasible to obtain UHMWPE that could be processed free of solvent to make uniaxial tapes and biaxial films, having unprecedented mechanical properties, exceeding that of the solution spun fibers. We address some of the fundamental aspects of chemistry, physics, rheology and processing for the development of desired morphological features to achieve the ultimate mechanical properties in tapes and films. The paper will also address the metastable melt state obtained on melting of the disentangled crystals and its implication on rheology in linear and nonlinear viscoelastic region. Solid state NMR studies will be applied to establish disentangled state in solid state to the polymerisation conditions. References: Macromolecules 2011, 44(14), 5558-5568; Nature Materials 2005, 4, 635-641; Phys Rev Lett 2006, 96(21), 218303-218205. The authors acknowledge financial support by the Dutch Polymer Institute.

  16. The head and neck anatomy of sea turtles (Cryptodira: Chelonioidea and skull shape in Testudines.

    Directory of Open Access Journals (Sweden)

    Marc E H Jones

    Full Text Available BACKGROUND: Sea turtles (Chelonoidea are a charismatic group of marine reptiles that occupy a range of important ecological roles. However, the diversity and evolution of their feeding anatomy remain incompletely known. METHODOLOGY/PRINCIPAL FINDINGS: Using computed tomography and classical comparative anatomy we describe the cranial anatomy in two sea turtles, the loggerhead (Caretta caretta and Kemp's ridley (Lepidochelys kempii, for a better understanding of sea turtle functional anatomy and morphological variation. In both taxa the temporal region of the skull is enclosed by bone and the jaw joint structure and muscle arrangement indicate that palinal jaw movement is possible. The tongue is relatively small, and the hyoid apparatus is not as conspicuous as in some freshwater aquatic turtles. We find several similarities between the muscles of C. caretta and L. kempii, but comparison with other turtles suggests only one of these characters may be derived: connection of the m. adductor mandibulae internus into the Pars intramandibularis via the Zwischensehne. The large fleshy origin of the m. adductor mandibulae externus Pars superficialis from the jugal seems to be a characteristic feature of sea turtles. CONCLUSIONS/SIGNIFICANCE: In C. caretta and L. kempii the ability to suction feed does not seem to be as well developed as that found in some freshwater aquatic turtles. Instead both have skulls suited to forceful biting. This is consistent with the observation that both taxa tend to feed on relatively slow moving but sometimes armoured prey. The broad fleshy origin of the m. adductor mandibulae externus Pars superficialis may be linked to thecheek region being almost fully enclosed in bone but the relationship is complex.

  17. The Union Defence Force Between the Two World Wars, 1919-1940

    Directory of Open Access Journals (Sweden)

    Ian Van der Waag

    2012-02-01

    Full Text Available South Africa was ill prepared for the Second World War. Her war potential was limited and Hitler is reputed to have laughed when the South African declaration came on 6 September 1939. The Permanent and Active Citizen Forces were under strength: the first comprised only 350 officers and some five thousand men. There were a further 122 000 men in the Commandos, of whom only 18 000 were reasonably equipped, and, being rurally based and overwhelmingly Afrikaans, many of these men did not support the war effort. Furthermore, training and training facilities were inadequate, there was a shortage of uniforms and equipment and, like the rest of the British Commonwealth, much of the doctrine had not kept pace with technological developments. This predicament developed over the preceding twenty years. The mechanisation of ground forces and the application of new technology for war contrasted sharply with developments in Europe. Although South Africa had the industrial capacity for the development of armour and mechanised forces, arguments based upon the nature of potential enemy forces, poor infrastructure and terrain inaccessibility combined with government policy and financial stringency resulted in nothing being done. Southern Africa, the focus of South African defence policy, was also thought to be unfavourable for mechanised warfare. Inadequate roads and multifarious geographic features concentrated energy on the development of the air arm for operations in Africa and a system of coastal defences to repel a sea assault, as well as a mix of British and Boer-type infantry supported by field artillery. As a result, an expeditionary force had to be prepared from scratch and the first South Africans to serve in the Second World War only left the country in July 1940. Yet the close relationship between the projected role of the Union Defence Force (UDF and the low priority given to force maintenance and weapons acquisition has been perceived by few

  18. Safety analysis and evaluation of the next fusion device

    International Nuclear Information System (INIS)

    As a part of safety evaluation, a probabilistic risk assessment (PRA) has been attempted for the Next Fusion Device system. Among the various events related to safety, a number of representative events have been selected for assessment, from the events in normal operation state, repair and maintenance state and accidental state. In the first chapter, in order to conduct the probabilistic risk assessment of the whole Fusion Experimental Reactor (FER), the data base required for the analysis was investigated in 1.1, the results on the failure mode and effects analysis (FMEA), accident sequence, radioactive inventory leakage flow path, event tree analysis (ETA) and fault tree analysis (FTA) were summarized in 1.2 to 1.5, respectively. Based on these results, accident initiating events were evaluated in 1.6, and overall risk was assessed in 1.7 and the tasks for the future were summarized in 1.8. It is important to analyze and evaluate various events during normal operations, repair and maintenance and accidents. However, due to the large uncertainties in the modeling of phenomena or the data base, there are many events for which realistic analyses are difficult. Three such events were selected and studied in chapter two. In 2.1, the temperature rise in the reactor structure after the Loss-of-Coolant-Accident caused by the decay heat under various heat removal conditions were investigated. In 2.2, the radiation dose of personnel during repair and maintenance period caused by the release of activated dust were estimated. Lastly, in 2.3 tritium behavior in the stainless steel first wall and graphite armour were studied. (author)

  19. Non-destructive testing of high heat flux components of fusion devices by infrared thermography: modeling and signal processing; Controle non destructif par thermographie infrarouge des composants face au plasma des machines de fusion controlee

    Energy Technology Data Exchange (ETDEWEB)

    Cismondi, F

    2007-07-01

    In Plasma Facing Components (PFCs) the joint of the CFC armour material onto the metallic CuCrZr heat sink needs to be significant defects free. Detection of material flaws is a major issue of the PFCs acceptance protocol. A Non-Destructive Technique (NDT) based upon active infrared thermography allows testing PFCs on SATIR tests bed in Cadarache. Up to now defect detection was based on the comparison of the surface temperature evolution of the inspected component with that of a supposed 'defect-free' one (used as a reference element). This work deals with improvement of thermal signal processing coming from SATIR. In particular the contributions of the thermal modelling and statistical signal processing converge in this work. As for thermal modelling, the identification of a sensitive parameter to defect presence allows improving the quantitative estimation of defect Otherwise Finite Element (FE) modeling of SATIR allows calculating the so called deterministic numerical tile. Statistical approach via the Monte Carlo technique extends the numerical tile concept to the numerical population concept. As for signal processing, traditional statistical treatments allow a better localization of the bond defect processing thermo-signal by itself, without utilising a reference signal. Moreover the problem of detection and classification of random signals can be solved by maximizing the signal-to-noise ratio. Two filters maximizing the signal-to-noise ratio are optimized: the stochastic matched filter aims at detects detection and the constrained stochastic matched filter aims at defects classification. Performances are quantified and methods are compared via the ROC curves. (author)

  20. Comparison of three types of full‐body compression garments on throwing and repeat‐sprint performance in cricket players

    Science.gov (United States)

    Duffield, Rob; Portus, Marc

    2007-01-01

    Objective To compare the effects of three types of full‐body compression garments (Skins, Adidas and Under Armour) on repeat‐sprint and throwing performance in cricket players. Methods Following familiarisation, 10 male cricket players performed four randomised exercise sessions (3 garments and a control). Each session involved a 30 min repeat‐sprint exercise protocol comprising 20 m sprints every minute, separated by submaximal exercise. Throwing tests included a pre‐exercise and a postexercise maximal distance test and accuracy throwing tests. During each session, measures of heart rate, skin temperature, change in body mass, rate of perceived exertion and perceived muscle soreness were recorded. Capillary blood samples were analysed before and after exercise for lactate, pH, O2 saturation and O2 partial pressure, and 24 h after exercise for creatine kinase (CK). Ratings of perceived muscle soreness were also obtained 24 h after exercise. Results No significant differences (p>0.05) were evident in repeat‐sprint performance (10 m, 20 m time or total submaximal distance covered) or throwing performance (maximum distance or accuracy). No significant differences (p>0.05) were observed in heart rate, body mass change or blood measures during exercise. Significant differences (p0.05). Conclusions No benefit was noted when wearing compression garments for repeat‐sprint or throwing performance; however, the use of the garments as a recovery tool, when worn after exercise, may be beneficial to reduce postexercise trauma and perceived muscle soreness. PMID:17341589

  1. Regarding Troy

    Directory of Open Access Journals (Sweden)

    Eleonora Cavallini

    2004-02-01

    Full Text Available Speaking of “historical mistakes” with reference to “Troy” is nonsense, for the simple reason that the movie is inspired to a myth, and the myth is the result of fantastic amplification and transfiguration of historical events. The Trojan war was very different from its poetical (not only Homeric representations: as historians such as Moses Finley showed, it was not a ten-year-long siege, but probably a series of short raids aiming at plunder. As a matter of fact, the post-Homeric epics describe Achilles as a thug and the Myrmidons as a band of robbers, spoiling temples and abducting daughters of priests. Besides, at the time of the Trojan war the Myceneans were considerably impoverished in comparison with the wealth of the previous centuries, and so they needed new lands to conquer and sack. Also the so-called “unfaithfulness” towards the Iliad is a false problem, if one considers that the myth of the Trojan war was told by many poets and writers in different ways and from different points of view (for instance, the authors of the Roman era, such as Virgilius, Seneca, Dracontius, show a deep sympathy for the Trojans, who were considered the ancestors of the Romans. Historical and archaeologic evedence can help us to understand the big efforts done by the filmamaker, but also by the production designer, in order to reproduce the epic atmosphere, and to appreciate the breathtaking battle sequences (particularly the duel between Hector and Achilles, the magnificent scenery (especially the palaces of Agamenon and Priamus, and the Greek camp, and the accuracy in reproducing weapons and armour, which contribute to personalize the single characters: for instance, just like in Homer, only Ajax fights in the Mycenean way, while Achilles and Hector employ more recent tactics.

  2. The corrosion of depleted uranium in terrestrial and marine environments.

    Science.gov (United States)

    Toque, C; Milodowski, A E; Baker, A C

    2014-02-01

    Depleted Uranium alloyed with titanium is used in armour penetrating munitions that have been fired in a number of conflict zones and testing ranges including the UK ranges at Kirkcudbright and Eskmeals. The study presented here evaluates the corrosion of DU alloy cylinders in soil on these two UK ranges and in the adjacent marine environment of the Solway Firth. The estimated mean initial corrosion rates and times for complete corrosion range from 0.13 to 1.9 g cm(-2) y(-1) and 2.5-48 years respectively depending on the particular physical and geochemical environment. The marine environment at the experimental site was very turbulent. This may have caused the scouring of corrosion products and given rise to a different geochemical environment from that which could be easily duplicated in laboratory experiments. The rate of mass loss was found to vary through time in one soil environment and this is hypothesised to be due to pitting increasing the surface area, followed by a build up of corrosion products inhibiting further corrosion. This indicates that early time measurements of mass loss or corrosion rate may be poor indicators of late time corrosion behaviour, potentially giving rise to incorrect estimates of time to complete corrosion. The DU alloy placed in apparently the same geochemical environment, for the same period of time, can experience very different amounts of corrosion and mass loss, indicating that even small variations in the corrosion environment can have a significant effect. These effects are more significant than other experimental errors and variations in initial surface area. PMID:24315120

  3. Environmental and health consequences of depleted uranium use in the 1991 Gulf War.

    Science.gov (United States)

    Bem, Henryk; Bou-Rabee, Firyal

    2004-03-01

    Depleted uranium (DU) is a by-product of the 235U radionuclide enrichment processes for nuclear reactors or nuclear weapons. DU in the metallic form has high density and hardness as well as pyrophoric properties, which makes it superior to the classical tungsten armour-piercing munitions. Military use of DU has been recently a subject of considerable concern, not only to radioecologists but also public opinion in terms of possible health hazards arising from its radioactivity and chemical toxicity. In this review, the results of uranium content measurements in different environmental samples performed by authors in Kuwait after Gulf War are presented with discussion concerning possible environmental and health effects for the local population. It was found that uranium concentration in the surface soil samples ranged from 0.3 to 2.5 microg g(-1) with an average value of 1.1 microg g(-1), much lower than world average value of 2.8 microg g(-1). The solid fallout samples showed similar concentrations varied from 0.3 to 1.7 microg g(-1) (average 1.47 microg g(-1)). Only the average concentration of U in solid particulate matter in surface air equal to 0.24 ng g(-1) was higher than the usually observed values of approximately 0.1 ng g(-1) but it was caused by the high dust concentration in the air in that region. Calculated on the basis of these measurements, the exposure to uranium for the Kuwait and southern Iraq population does not differ from the world average estimation. Therefore, the widely spread information in newspapers and Internet (see for example: [CADU NEWS, 2003. http://www.cadu.org.uk/news/index.htm (3-13)]) concerning dramatic health deterioration for Iraqi citizens should not be linked directly with their exposure to DU after the Gulf War. PMID:14664872

  4. Time-pickoff techniques for an extramely low-background anticoincidence spectrometer

    International Nuclear Information System (INIS)

    The effects of the time-pickoff techniques on resolving time and of the resolving time on background suppression factor have been examined for a Ge-NaI(Tl) anticoincidence spectrometer. This spectrometer was designed to measure extremely low-level radioactivity. A 14.9 %-relative-efficiency Ge crystal served as the spectroscopy detector and was operated in the slow anticoincidence with the two NaI(Tl) crystals of which sizes were 8'' diam. x 8'' long(annulus type) and 3'' diam. x 3'' long(solid type). The detector system was placed inside a shield consisted of 10 cm-thick lead plates and 5 cm-thick steel armour plates. When the spectrometer was operated in the mode of Constant Fraction-Leading Edge(CF-LE) time-pickoff, the most effective suppression of the secondary cosmic-ray background was achieved with the shortest resolving time of 0.80 μs. In the case of CF-CF time-pickoff, the resolving time of 2.5 μs was necessary to obtain the same suppression effect as in the CF-LE time-pickoff. The count-rate of background continuum of the anticoincidence spectrum was reduced to 7.5 x 10-5 counts/s.keV at 661 keV and to 2.3 x 10-5 counts/s.keV at 1332 keV. These low count-rates resulted in an average reduction of the single-spectrum background of approx. 80 %. Lower limit of detection of the spectrometer for 137Cs activity was evaluated to be 7.4 pCi +- 10 % and 1.5 pCi +- 30 % when the count-time was 40 k seconds. (author)

  5. Characterisation and dissolution of depleted uranium aerosols produced during impacts of kinetic energy penetrators against a tank

    International Nuclear Information System (INIS)

    Aerosols produced during impacts of depleted uranium (DU) penetrators against the glacis (sloping armour) and the turret of a tank were sampled. The concentration and size distribution were determined. Activity median aerodynamic diameters were 1 μm (geometric standard deviation, sg = 3.7) and 2 μm (sg = 2.5), respectively, for glacis and turret. The mean air concentration was 120 Bq m-3, i.e. 8.5 mg m-3 of DU. Filters analysed by scanning electron microscopy (SEM) and X ray diffraction showed two types of particles (fine particles and large molten particles) composed mainly of a mixture of uranium and aluminium. The uranium oxides were mostly U3O8, UO2.25 and probably UO3.01 and a mixed compound of U and Al. The kinetics of dissolution in three media (HCO3-, HCl and Gamble's solution) were determined using in-vitro tests. The slow dissolution rates were respectively slow, and intermediate between slow and moderate, and the rapid dissolution fractions were mostly intermediate between moderate and fast. According to the in-vitro results for Gamble's solution, and based on a hypothetical single acute inhalation of 90 Bq, effective doses integrated up to 1 y after incorporation were 0.54 and 0.56 mSv respectively, for aerosols from glacis and turret. In comparison, the ICRP limits are 20 mSv y-1 for workers and 1 mSv y-1 for members of public. A kidney concentration of approximately 0.1 μg U g-1 was predicted and should not, in this case, lead to kidney damage. (author)

  6. LORICA - A new model for linking landscape and soil profile evolution: Development and sensitivity analysis

    Science.gov (United States)

    Temme, Arnaud J. A. M.; Vanwalleghem, Tom

    2016-05-01

    Soils and landscapes evolve in tandem. Landscape position is a strong determinant of vertical soil development, which has often been formalized in the catena concept. At the same time, soil properties are strong determinants of geomorphic processes such as overland erosion, landsliding and creep. We present a new soilscape evolution model; LORICA, to study these numerous interactions between soil and landscape development. The model is based on the existing landscape evolution model LAPSUS and the soil formation model MILESD. The model includes similar soil formation processes as MILESD, but the main novelties include the consideration of more layers and the dynamic adaption of the number of layers as a function of the soil profile's heterogeneity. New processes in the landscape evolution component include a negative feedback of vegetation and armouring and particle size selectivity of the erosion-deposition process. In order to quantify these different interactions, we present a full sensitivity analysis of the input parameters. First results show that the model successfully simulates various soil-landscape interactions, leading to outputs where the surface changes in the landscape clearly depend on soil development, and soil changes depend on landscape location. Sensitivity analysis of the model confirms that soil and landscape interact: variables controlling amount and position of fine clay have the largest effect on erosion, and erosion variables control among others the amount of chemical weathering. These results show the importance of particle size distribution, and especially processes controlling the presence of finer clay particles that are easily eroded, both for the resulting landscape form as for the resulting soil profiles. Further research will have to show whether this is specific to the boundary conditions of this study or a general phenomenon.

  7. Erosion of organic matter from sandy soils: solving the mass balance

    Science.gov (United States)

    Kuhn, N. J.; Armstrong, E. K.

    2012-04-01

    Globally, soils contain an estimated 1500GT of carbon, over twice that present in the atmosphere (IPCC, 2001). However the role of soils in the global carbon cycle remains highly contentious. Soil erosion redistributes organic matter (OM) within landscapes, and takes place at a range of scales from mass movement to inter-rill erosion. It is known that inter-rill erosion occurring on clay-rich stable soils causes sediment to become enriched in OM by up to a factor of 6.2 (Mora et al., 2007). However, maintenance of mass dictates that such enrichment can only be temporary unless erosion ceases due to armouring. The lack of studies showing a decline in OM erosion is attributed to the well-aggregated, slow-crusting soils used in such research. Thus, this investigation aimed to investigate the erosion of OM from rapid-crusting, sandy soils. Soils from both organically and conventionally farmed land from Shropshire, UK, were exposed to simulated rainfalls differing in both intensity and kinetic energy. The texture and OM content of soil crusts and eroded sediment were analysed. OM was enriched by more than 10% in one test only, but reduced significantly during two soil and rainfall combinations. Analysis of crust and sediment texture showed that the interaction between crust development and rainfall erosivity was responsible for the varying OM enrichment. The results also confirmed that, for practical erosion applications, the maintenance of the mass of OM has to be considered. Accordingly, a key requirement for the correct assessment of OM erosion is the proper assessment of the interaction between surface and rainfall over time in each erosion system.

  8. Engineering activities on the ITER representative diagnostic equatorial port plug

    International Nuclear Information System (INIS)

    Most of ITER diagnostic systems are integrated in port plugs, which are water cooled stainless steel structures inserted into the vacuum vessel ports. The port plug must provide basic functions such as neutron and gamma shielding, supporting the first wall armour (BSM), closing the vacuum vessel ports, while supporting the diagnostic equipments. ITER diagnostic port plug must resist a severe environment like high temperature due to neutron interaction with the structures and high electromechanical loading during disruptions events. CEA has contributed to the design and integration tasks in the frame of the representative equatorial port plug EQ no. 01, in particular on the engineering, structural and thermal finite element analysis. These detailed analyses have highlighted some design issues which were worked out through different solutions. This paper contains a description of the engineering activities performed such as: -The static mechanical calculations of the top plate closure system under disruption load. -The static mechanical calculations of the BSM attachment to the port plug. These two first studies led to design changes proposals which significantly improved the behaviour of the structures but also showed that the safety margin with respect to design limits is quite low. -The design of a Diagnostic Shield Module (DSM) integrated inside the port plug and a proposition of attachment scheme, with respect to disruption loads. The manufacturing of the DSM has been taken into account, as well as diagnostic integration inside the structure and maintenance aspects. -The thermal assessment of the port plug under neutronic load during normal operation, with the optimization of the cooling system. The maximum temperature calculated in normal operation has been reduced from 900 deg. C to less than 400 deg. C in the front plate; and the cooling arrangement at the back of the port plug has been simplified without important temperature increase.

  9. Graves hyperthyroidism 131I treatment the clinical curative effect of observation

    International Nuclear Information System (INIS)

    Objective: to study the clinical treatment of 131I Graves hyperthyroidism curative effect. Methods: the clinical data of Graves hyperthyroidism patients were retrospectively analyzed. Results: 258 cases of patients with hyperthyroidism Graves. 131I treatment 1∼2 times after healed 200 cases, improvement of 38 patients, a low, 10 cases were invalid 10 cases failure; the total effective 96.12%. 1 year after treatment 131I thyroid quality by before treatment 43.6 + 20.9 grams shrinks to 1.98 + 18.5 grams (p131I before treatment with prominent eyes 68 cases (26.4%) 131I after treatment, the prominent eyes healed 24 cases (34.8%), improvement 30 patients (43.5%), invalid in 12 cases (17.4%), aggravating in 2 cases (2.9%), efficient for 79.7%. Concurrent hyperthyroidism 131I before treatment in patients with 31 patients (heart), after the treatment of 131I 12.0% in 25 patients recovered, 6 patients get better, efficient 100%. After the treatment of 131I temporary armor low in 25 patients (9.7%) , permanent armour low 27 cases (10.5%). After the treatment of 131I 15 cases have been reduced to a sex WBC (5.8%), 8 cases of liver function mild damage (3.1%), 13 cases itchy skin (1 case), cholesterol by 5.0% compared appear suspected hyperthyroidism crises (0.4%). 258 patients with thyroid type micronodular 41 cases, treatment cured after 131I in 25 patients (61.0%), improvement in 16 (39.0%), laseris 100%, Diffuse 217 example, cure 175 cases (80.6%), improvement 22 patients (10%), a low 10 (4.6%), invalid 10 (4.6%), laseris 95.4 percent. Conclusion: 131I treatment Graves hyperthyroidism is simple, safe, effective, and can be used as the preferred treatment method outperforms that of anti-thyroid drugs. (authors)

  10. 'Heart-talk:' considering the role of the heart in therapy as evidenced in the Quran and medical research.

    Science.gov (United States)

    Hussain, Feryad

    2013-12-01

    The emphasis on scientific approaches and evidence-based therapy has been a key force in developing and refining existing models of therapy. While this has been unquestioningly invaluable, it has similarly restricted the development and so implementation of those models that do not lend themselves easily to current research methodology, since the lack of evidence-practice research means they are not considered as 'legitimate' therapeutic practice. That the mind and body have an inter-dependent relationship is readily evidenced in numerous religious texts, but the lack of acknowledgement of that relationship in contemporary therapeutic approaches means that patients are not able to benefit from its use in sessions. Ironically, it is current developments in medical research that have discovered the reality around this relationship that have enabled such models to be further explore within an accepted context of evidence-based practice. This paper highlights the relationship between the heart and brain function as evidenced with brief reference to Quranic verses and medical (namely, neurocardiological) research. Further, it raises questions around the implications of this information for therapists working in both physical and mental health. The concept of 'heart talk' is an extension of the term 'heart brain' coined by Dr Armour (Professor of Pharmacology) in 1991 and is suggestive of its use in the world of psychological therapy. It relates to those cognitions which patients suggest come 'from the heart' which though previously dismissed are now suggestive of having some scientific basis and are potentially a legitimate source of information in understanding patients experiences. PMID:22170484

  11. Una nueva pieza de artilleria de galeras del siglo XVI: el esmeril bastardo «matacapitanes»

    Directory of Open Access Journals (Sweden)

    Fondevila Silva, Pedro

    2012-12-01

    Full Text Available This work is aimed at the analysis of an unknown piece of maritime artillery dated at the second half of the XVIth century. This piece, out of any inventory record, was located within one of the Archive-Museum chambers in the Don Álvaro Bazán Palace at El Viso del Marqués, Ciudad Real province, central Spain. The specimen is a bastard esmeril here so-called «matacapitanes» («killer of captains» because it seems precisely designed to be used against the bullet-proof armour of enemy officers. By means of manuscripts and impressed documents, an approach and discussion on the typology and classification of the XVIth century´s maritime artillery is also presented.

    Trabajo de investigación que presenta y analiza una pieza desconocida de artillería naval de la segunda mitad del siglo XVI, localizada sin inventariar en una de las salas del Archivo-Museo «Don Álvaro de Bazán» del Palacio de El Viso del Marqués en Ciudad Real (España. Se trata de un esmeril bastardo que hemos bautizado como «matacapitanes », por ser un modelo diseñado para optimizar su empleo contra los oficiales enemigos protegidos con armaduras a prueba de balas de arcabuz. Además, se realiza una aproximación al estudio de la tipología y clasificación de la artillería naval del siglo XVI a través de los documentos, tanto manuscritos como impresos, de esa época.

  12. Carbon-carbon composite and copper-composite bond damages for high flux component controlled fusion

    International Nuclear Information System (INIS)

    Plasma facing components constitute the first wall in contact with plasma in fusion machines such as Tore Supra and ITER. These components have to sustain high heat flux and consequently elevated temperatures. They are made up of an armour material, the carbon-carbon composite, a heat sink structure material, the copper chromium zirconium, and a material, the OFHC copper, which is used as a compliant layer between the carbon-carbon composite and the copper chromium zirconium. Using different materials leads to the apparition of strong residual stresses during manufacturing, because of the thermal expansion mismatch between the materials, and compromises the lasting operation of fusion machines as damage which appeared during manufacturing may propagate. The objective of this study is to understand the damage mechanisms of the carbon-carbon composite and the composite-copper bond under solicitations that plasma facing components may suffer during their life. The mechanical behaviours of carbon-carbon composite and composite-copper bond were studied in order to define the most suitable models to describe these behaviours. With these models, thermomechanical calculations were performed on plasma facing components with the finite element code Cast3M. The manufacturing of the components induces high stresses which damage the carbon-carbon composite and the composite-copper bond. The damage propagates during the cooling down to room temperature and not under heat flux. Alternative geometries for the plasma facing components were studied to reduce damage. The relation between the damage of the carbon-carbon composite and its thermal conductivity was also demonstrated. (author)

  13. Modelling gastric evacuation in gadoids feeding on crustaceans.

    Science.gov (United States)

    Andersen, N G; Chabot, D; Couturier, C S

    2016-05-01

    A mechanistic, prey surface-dependent model was expanded to describe the course and rate of gastric evacuation in predatory fishes feeding on crustacean prey with robust exoskeletons. This was accomplished by adding a layer of higher resistance to the digestive processes outside the inner softer parts of a prey cylinder abstraction and splitting up the prey evacuation into two stages: an initial stage where the exoskeleton is cracked and a second where the prey remains are digested and evacuated. The model was parameterized for crustaceans with different levels of armour fed to Atlantic cod Gadus morhua or whiting Merlangius merlangus and recovered from the stomachs at different post-prandial times. The prey species were krill Meganyctiphanes norvegica; shrimps and prawns Crangon crangon, Pandalus borealis, Pandalus montagui and Eualus macilentus; crabs Liocarcinus depurator and Chionoecetes opilio. In accordance with the apparent intraspecific isometric relationship between exoskeleton mass and total body mass, the model described stage duration and rate of evacuation of the crustacean prey independently of meal and prey sizes. The duration of the first stage increased (0-33 h) and the evacuation rate of both stages decreased (by a half) with increasing level of the crustacean armament in terms of chitin and ash. A common, interspecific parameterization of the model within each of the categories krill, shrimp and crab can probably be used if the contents of chitin and ash are similar among prey species per prey category. The model offers a simple way for estimating evacuation rates from stomach content data in order to obtain food consumption rates of wild fishes, provided that information about digestion stage of crustacean prey is available. PMID:27170110

  14. IR sensor design insight from missile-plume prediction models

    Science.gov (United States)

    Rapanotti, John L.; Gilbert, Bruno; Richer, Guy; Stowe, Robert

    2002-08-01

    Modern anti-tank missiles and the requirement of rapid deployment have significantly reduced the use of passive armour in protecting land vehicles. Vehicle survivability is becoming more dependent on sensors, computers and countermeasures to detect and avoid threats. An analysis of missile propellants suggests that missile detection based on plume characteristics alone may be more difficult than anticipated. Currently, the passive detection of missiles depends on signatures with a significant ultraviolet component. This approach is effective in detecting anti-aircraft missiles that rely on powerful motors to pursue high-speed aircraft. The high temperature exhaust from these missiles contains significant levels of carbon dioxide, water and, often, metal oxides such as alumina. The plumes emits strongest in the infrared, 1 to 5micrometers , regions with a significant component of the signature extending into the ultraviolet domain. Many anti-tank missiles do not need the same level of propulsion and radiate significantly less. These low velocity missiles, relying on the destructive force of shaped-charge warhead, are more difficult to detect. There is virtually no ultraviolet component and detection based on UV sensors is impractical. The transition in missile detection from UV to IR is reasonable, based on trends in imaging technology, but from the analysis presented in this paper even IR imagers may have difficulty in detecting missile plumes. This suggests that the emphasis should be placed in the detection of the missile hard body in the longer wavelengths of 8 to 12micrometers . The analysis described in this paper is based on solution of the governing equations of plume physics and chemistry. These models will be used to develop better sensors and threat detection algorithms.

  15. On the origin of optics

    Science.gov (United States)

    Parker, Andrew R.

    2011-03-01

    The first optical devices in animals evolved in the Cambrian period. The first reflector known dates from around 508 million years ago (Ma); the first eyes with lenses evolved at around 521 Ma. Consideration of the introduction of vision leads to a hypothesis for the cause of evolution's Big Bang—the Cambrian explosion. Suddenly, and for no obvious reason, the range and variety of life-forms erupted somewhere between 520 and 515 Ma (as limited by of our dating techniques). At no other time in Earth's history there has been such a profusion, such an exuberance, and such an overwhelming diversity in so short time, within one million years. Prior to this Cambrian explosion event, all animals were soft-bodied and mainly worm-like, as they had been for millions of years before that. But during the Cambrian explosion many of the major animal groups on Earth today independently evolved their hard body parts for the first time. Following the appearance of the first trilobites, some animals evolved shells and spines, some with bright colours, to visually warn of their new armour. Others evolved streamlined appearances and swimming oars to advise trilobites that they could not be caught. The Light Switch Theory provides an explanation for what triggered this event—that it was the development of vision (in trilobites); the introduction of optics. Once visual capability arose, it allowed predators to identify prey, triggering an arms race. From here on, vision became a dominant force of evolution and resulted in the eyes and reflecting optics that we have in nature today. This paper provides a summary of the first optical devices to evolve in animals, along with the implications of these in their relevance to the Big Bang of evolution, written for the physical sciences.

  16. Characteristics and Application of Vertical Ring High Gradient Magnetic Separator%LHGC-F型立环高梯度磁选机的特性及其应用

    Institute of Scientific and Technical Information of China (English)

    王兆连; 刘风亮; 贾洪利; 魏黎明; 曾亮亮; 王宝春; 田凌佳; 张金庆

    2013-01-01

    On the basis of LHGC-vertical ring high gradient magnetic separator which has been developed and used successfully, LHGC-F oil-water compound-coolimg vertical ring high gradient magnetic separator is also developed by Shandong Huate Magnet Technology Co., Ltd., and it was appraised at the provincial and ministerial level on July 2012. The coil of the magnetic separator is cooled by transform oil, and the oil is cooled by water, so the coil can reach fine cooling effect. Meantime, the two ends of coil are fitted with armour, it can avoid magnetic leakage, improve the utilization ratio of magnetic energy, the background field of the magnetic separator reachs 1.3T, and the magnetic separator has yet some other advantages, now the magnetic separator has been applied in the separations of nonmetallic minerals effectively.%在成功研制和应用强制油冷立环高梯度磁选机的基础上,华特又研制出第四代油水复合冷却立环高梯度磁选机,并于2012年7月初通过省部级鉴定.该磁选机线圈用油冷却,油又用水冷却,线圈达到良好的降温效果,同时在线圈两端加装铁铠,防止漏磁,提高磁能利用率,背景场强达到1.3T,因诸多优点而在非金属矿选矿成功应用.

  17. Protivoklopni vođeni projektili zapadne Evrope, Izraela i Indije / Anti-tank guided missiles of western Europe, Israel and India

    Directory of Open Access Journals (Sweden)

    Goran M. Lazić

    2010-10-01

    Full Text Available Protivoklopni vođeni projektili namenjeni su za uništavanje teško-oklopljenih tenkova, kao i drugih oklopnih vozila. Ovaj rad nudi istorijsko-tehnički pregled (razvoj projektila kroz generacije i osnovni podaci vezani za borbeno-operativno dejstvo ovih projektila ovog tipa naoružanja koje poseduju zemlje zapadne Evrope, Izraela i Indije. Pored osnovnih podataka navode se i cene nekih projektila ponaosob, kao i tendencije razvoja u ovoj grani naoružanja. / Anti-tank guided missiles are designed to hit and destroy heavily armored tanks and other armored fighting vehicles. This review offers a historical and technical overview (development of missiles throughout generations and basic data about combat and operational actions of this type of weapons in Western Europe, Israel and India. The review also offers prices of some missiles and tendencies of development in this branch. Anti-tank guided missiles are primarily designed to destroy armoured tanks as well as other armoured vehicles. Anti-tank guided systems differ in size, from small ones (shoulder-launched missile weapons carried by a single person to complex weapon systems (crewserved, vehicle-mounted and airborne systems. The first generation of anti-tank guided missiles is a manually guided MCLOS (Manual Command to Line of Sight projectile requiring an operator to guide and steer it to a target by a joystick. Vickers vigilant is a British anti-tank wire-guided missile, produced in 1956. The Bantam (Bofors Anti-Tank Missile or Robot 53 (RB 53 is a Swedish anti-tank wire-guided missile, produced in 1963. Cobra is a German - Swiss product which entered the operational use in 1956. It was replaced by Cobra 2000 and Mamaba systems, which are anti-tank guided missiles of the first generation, but with improved guidance and electronics. ENTAC (Engin téléguidé anti-char or MGM Petronor-32A is a French anti-tank wire-guided missile, widely spread and still in the operational use in many

  18. Evaluation of the Erosion on the CFC tiles of the ITER Divertor by means o f FE calculations

    International Nuclear Information System (INIS)

    Full text of publication follows: The vertical target of the ITER divertor is armoured with Carbon Fibre Composite (CFC) mono-blocks in the lower part. This part is subjected to the maximum power and particles loads and, consequently, has a risk of high erosion and a significant risk of failure. In order to calculate the erosion during operation an original methodology has been developed using the CASTEM CEA finite element code. The calculation is based on a series of steady states the mesh being updated at each step of the iteration taking into account the rate of erosion between two steps. The model was developed thanks to the routines developed 10 years ago for the toroidal pump limiter of Tore Supra and takes into account shadowing effect and possible penetration of power into the gap between two mono-blocks. Both physical and chemical sputtering together with sublimation have been included in the code to describe the loss of material by the thermal and particle loads envisaged for ITER normal operation regime. This model has been validated by comparison with analytical or other code results. As erosion instability in normal operation in case of one faulty mono-block besides good ones due to the balanced rate between the various erosion mechanisms at different temperatures can be expected, coherent plasma parameters, which represent the worse cases of erosion in normal operation, have been taken into account to analyse the erosion behaviour of the mono-blocks. The aim of the study was also to evaluate the influence of a mono-block defect on erosion behaviour and the impact of these phenomena on the mono-block acceptance criteria. The calculations have pointed out the occurrence of some erosion instabilities for the studied cases (neighbour mono-block with reduced conductivity or with 90 deg. defects). Moreover it was shown that, when applying 20 MW/m2 to the erosion model already subjected to the normal condition loads for 10,000 s, the plasma shaping of the

  19. GREEN DIPLOMACY-A NEW TYPE OF INTERNATIONAL COOPERATION (II

    Directory of Open Access Journals (Sweden)

    Elena IFTIME

    2014-07-01

    s natural heritage. The efforts made for creating an institutional structure with international character in which environmental problems had to be debated, took shape and finality on organizing some meetings on this theme that reached its climax by institutionalizing the so-called “green Summits”: Stockholm (1972; Rio de Janeiro (1992; Johannesburg (2002. These meetings remained as milestones in the field, through international documents adopted, which constituted the legal armour to fight for nature’s protection.

  20. Technology Programme

    International Nuclear Information System (INIS)

    The technology activities carried out by the Euratom-ENEA Association in the framework of the European Fusion Development Agreement concern the Next Step (International Thermonuclear Experimental Reactor - ITER), the Long-Term Programme (breeder blanket, materials, International Fusion Materials Irradiation Facility - IFMIF), Power Plant Conceptual Studies and Socio-Economic Studies. The Underlying Technology Programme was set up to complement the fusion activities as well to develop technologies with a wider range of interest. The Technology Programme mainly involves staff from the Frascati laboratories of the Fusion Technical and Scientific Unit and from the Brasimone laboratories of the Advanced Physics Technologies Unit. Other ENEA units also provide valuable contributions to the programme. ENEA is heavily engaged in component development/testing and in design and safety activities for the European Fusion Technology Programme. Although the work documented in the following covers a large range of topics that differ considerably because they concern the development of extremely complex systems, the high level of integration and coordination ensures the capability to cover the fusion system as a whole. In 2004 the most significant testing activities concerned the ITER primary beryllium-coated first wall. In the field of high-heat-flux components, an important achievement was the qualification of the process for depositing a copper liner on carbon fibre composite (CFC) hollow tiles. This new process, pre-brazed casting (PBC), allows the hot radial pressing (HRP) joining procedure to be used also for CFC-based armour monoblock divertor components. The PBC and HRP processes are candidates for the construction of the ITER divertor. In the materials field an important milestone was the commissioning of a new facility for chemical vapour infiltration/deposition, used for optimising silicon carbide composite (SiCf/SiC) components. Eight patents were deposited during 2004

  1. On tungsten technologies and qualification for DEMO

    International Nuclear Information System (INIS)

    Tungsten alloys are considered prime candidates for the in-vessel components directly facing the plasma. For example, in the HEMJ helium cooled divertor design tiles may be operated at temperatures up to 1700 deg. C, supported by a structure partially consisting of tungsten at temperatures from 600 to 1000 deg. C, and connected to a HT steel structure. The tungsten armoured primary wall is operated at 500-900 deg. C. Irradiation doses will be few tens dpa at minimum, but FPR requirements for plants availability will stretch these targets. Recently injection moulding technology was developed for pure tungsten and representative parts were manufactured for ITER monobloc divertors and DEMO HEMJ thimbles. The major advantages for this technology are the efficient use of material feedstock/resources and the intrinsic possibility to produce near-finished product, avoiding machining processes that are costly and may introduce surface defects deteriorating the component in service performance. It is well suited for mass-manufacturing of components as well known in e.g. lighting industries. To further qualify this material technology various specimen types were produced with processing parameters identical to the components, and tested successfully, showing the high potential for implementation in (fusion) devices. Furthermore, the engineering approach can clearly be tailored away from conventional design and manufacturing technologies based on bulk materials. The technology is suitable for shaping of new W-alloys and W-ODS variants as well. Basically this technology allows a particular qualification trajectory. There is no need to produce large batches of material during the material development and optimization stage. For the verification of irradiation behaviour in the specific neutron spectra, there is a further attractive feature to use e.g. isotope tailored powders to adjust to available irradiation facilities like MTR's. In addition the ingrowth of transmutation

  2. Recent morphological changes in the Mekong and Bassac river channels, Mekong delta: The marked impact of river-bed mining and implications for delta destabilisation

    Science.gov (United States)

    Brunier, Guillaume; Anthony, Edward J.; Goichot, Marc; Provansal, Mireille; Dussouillez, Philippe

    2014-11-01

    The Mekong delta, in Vietnam, is the world's third largest delta. Densely populated, the delta has been significantly armoured with engineering works and dykes to protect populations and infrastructure from storms, and shrimp farms from saltwater intrusion. Considerable development pressures in Vietnam and in the upstream countries have resulted in the construction of several dams in China and in important channel-bed aggregate extractions especially in Cambodia. The effects of these developments impact the delta dynamics in various ways. In this study, changes in the channel morphology of the Mekong proper and the Bassac, the two main distributaries in the 250 km-long deltaic reach from the Cambodian border to the coast, were analysed using channel depth data for 1998 and 2008. The channels display important and irregular bed changes over the 10-year comparison period, including significant incision and expansion and deepening of numerous pools. The mean depth of both channels increased by more than 1.3 m. Both channels also showed correlative significant bed material losses: respectively 90 million m3 in the Mekong and 110 million m3 in the Bassac over the 10-year period. These important losses over a relatively short period, and weak correlations between bed incision and hydraulic parameters suggest that the marked morphological changes are not in equilibrium with flow and sediment entrainment conditions, and are therefore not related to changes in river hydrology. We claim that aggregate extraction, currently practised on a very large scale in the Mekong delta channels and upstream of the delta, is the main cause of these recent morphological changes. These changes are deemed to contribute actively to rampant bank erosion in the delta as well as to erosion of the Mekong delta shoreline. Other contributory activities include the numerous dykes and embankments. The role of existing dams in bed losses remains unclear in the absence of reliable data on the Mekong

  3. Evaluation of energy and particle impact on the plasma facing components in DEMO

    International Nuclear Information System (INIS)

    Highlights: ► We analyze the first wall blanket W/EUROFER configuration for DEMO under steady-state normal operation and off-normal conditions, such as vertical displacements events (VDE) and runaway electrons (RE). The main issue is to find the optimal thickness of the W armor which will prevent tungsten surface from evaporation and melting and, on the other hand, will keep EUROFER below the critical thermal stresses. ► The minimum thickness of the tungsten amour about 3 mm for W/EUROFER sandwich structure will keep the maximum EUROFER temperature below the critical limit for EUROFER steel under steady-state operation and ITER like cooling conditions. ► The W surface temperature and the max. EUROFER temperature are increasing with incoming heat flux. For reference conditions (Dw ∼3 mm, DEUROFER ∼4 mm) the maximum tolerable heat flux which does not causes in thermal stresses in structural material is about ∼13.5 MW/m2. ► The RE deposit their energy deeper into W armour and for energies ≥50 MJ/m2 and deposition times ≤0.1 s, the minimum armor thickness required to prevent EUROFER from thermal distraction is ≥1.4 cm. ► However, at this thickness the W surface melts. For higher RE energy deposition rates (≥100 MJ/m2 in 0.1 s), the required armor thickness to prevent thermal destruction is even larger so that the bulk of the armor layer will melt and evaporate. - Abstract: We analyze the first wall blanket W/EUROFER configuration for DEMO under steady-state normal operation and off-normal conditions, such as vertical displacement events (VDE) and runaway electrons (RE). The main issue is to find the optimal thickness of the W armor which will prevent tungsten surface from evaporation and melting and, on the other hand, will keep EUROFER below the critical thermal stresses. Under steady-state operation heat transfer into the coolant must remain below the critical heat flux (CHF) to avoid the possible severe degradation of the coolant heat removal

  4. Evaluation of energy and particle impact on the plasma facing components in DEMO

    Energy Technology Data Exchange (ETDEWEB)

    Igitkhanov, Yuri, E-mail: juri.gitkhanov@ihm.fzk.de [Karlsruhe Institute of Technology, IHM, Karlsruhe (Germany); Bazylev, Boris [Karlsruhe Institute of Technology, IHM, Karlsruhe (Germany)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer We analyze the first wall blanket W/EUROFER configuration for DEMO under steady-state normal operation and off-normal conditions, such as vertical displacements events (VDE) and runaway electrons (RE). The main issue is to find the optimal thickness of the W armor which will prevent tungsten surface from evaporation and melting and, on the other hand, will keep EUROFER below the critical thermal stresses. Black-Right-Pointing-Pointer The minimum thickness of the tungsten amour about 3 mm for W/EUROFER sandwich structure will keep the maximum EUROFER temperature below the critical limit for EUROFER steel under steady-state operation and ITER like cooling conditions. Black-Right-Pointing-Pointer The W surface temperature and the max. EUROFER temperature are increasing with incoming heat flux. For reference conditions (Dw {approx}3 mm, DEUROFER {approx}4 mm) the maximum tolerable heat flux which does not causes in thermal stresses in structural material is about {approx}13.5 MW/m{sup 2}. Black-Right-Pointing-Pointer The RE deposit their energy deeper into W armour and for energies {>=}50 MJ/m{sup 2} and deposition times {<=}0.1 s, the minimum armor thickness required to prevent EUROFER from thermal distraction is {>=}1.4 cm. Black-Right-Pointing-Pointer However, at this thickness the W surface melts. For higher RE energy deposition rates ({>=}100 MJ/m{sup 2} in 0.1 s), the required armor thickness to prevent thermal destruction is even larger so that the bulk of the armor layer will melt and evaporate. - Abstract: We analyze the first wall blanket W/EUROFER configuration for DEMO under steady-state normal operation and off-normal conditions, such as vertical displacement events (VDE) and runaway electrons (RE). The main issue is to find the optimal thickness of the W armor which will prevent tungsten surface from evaporation and melting and, on the other hand, will keep EUROFER below the critical thermal stresses. Under steady

  5. Energy-resolved photoemission studies of Be-containing surfaces for fusion; Energievariierte Photoemissionsstudien an berylliumhaltigen Oberflaechen fuer die Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Koeppen, Martin

    2013-02-04

    Fusion research aims at the exploitation of the deuterium-tritium reaction for energy production. Next step on the roadmap is the construction of the experimental reactor ITER. The three elements beryllium, carbon and tungsten are to be used as armour materials for the vacuum vessel. After erosion due to plasma processes, these materials are transported and redeposited together with plasma impurities like oxygen from surface oxides. This leads to the formation of compounds by chemical reactions and diffusive processes, induced both by elevated temperatures and implantation of energetic particles. Due to the complexity of the induced surface processes, a method is required which is capable of both qualitative and quantitative analysis of the involved chemical species. X-ray photoelectron spectroscopy (XPS) provides the chemical analysis. Since diffusive processes play an important role in solid-state reactions, a depth-resolved method is required. In this work, energy-resolved XPS using synchrotron radiation with variable photon energies is extended towards a quantitative depth-resolved analysis. For the quantitative analysis a new model is derived which calculates the depth-resolved composition and the respective composition-dependent electron inelastic mean free path in a self-consistent way. Input is the XPS data which is normalized with all parameters influencing the photoelectron intensities. This fully quantitative model is applied to describe the interaction of energetic oxygen ions with the beryllium-tungsten alloy Be{sub 2}W. Oxygen ions from the plasma are able to interact with plasma facing materials. Formation of Be{sub 2}W is to be expected at the first wall and in the divertor region of ITER. Irradiation of this alloy leads to its decompositions. After decomposition, formation of beryllium oxide BeO is preferred compared to formation of tungsten oxides. Heating to 600K leads to chemical reduction of tungsten oxides. Metallic Be acts as reduction agent

  6. Depleted uranium: A study of its uses in the UK and disposal issues

    Energy Technology Data Exchange (ETDEWEB)

    Russ, Bob

    2002-03-01

    Full text: The Environment Agency recently published a contract R and D report, by John Jackson of Alan Martin Associates, on depleted uranium (DU). The report documents a scoping study on the uses of DU; the civil non-nuclear applications for DU were a particular focus of the scoping study. The study was commissioned following a series of DU related incidents, including the crash of the Korean Airlines' Boeing 747 at Stansted in late 1999. There had also been an assertion in the Guardian (21 August 2000) that as much as 50 tonnes of DU is lying in UK scrapyards. The report confirms that the quantities referred to in the Guardian are groundless. The report provides information and guidance to the Agency's staff who regulate radioactive substances in England and Wales. The report does not attempt to review the health effects of DU (separate health studies have been carried out by the Royal Society and others). A range of non-nuclear uses of DU are identified in the report: Transportable shielded containers for radioactive sources, Aircraft counterbalance weights, Piling equipment (civil engineering), Radiation shielding (hospitals, universities, etc), Armour piercing ammunition, Uranium catalysts, and Ceramic glazes. The report concludes that there is, in total, less than 50 tonnes of DU in use in the UK outside of military and nuclear applications. The report identifies the aircraft salvage and recycling industry as having a significant risk of DU being lost from regulatory control. (Awareness and vigilance need to be maintained; in February 2001 in Ohio, USA, 53 tonnes of aluminium ingots from an aircraft recycling operation were found to be contaminated with DU from counterweights that had not been segregated prior to smelting.) The report highlights the absence of a UK disposal route for substantial quantities of DU. The BNFL site at Drigg cannot accept DU because in its undiluted state it is categorised as intermediate level waste. Whilst redundant DU

  7. WIDE-BLAD AXES «BALTA» FROM THE COLLECTION OF THE OMSK STATE HISTORY MUSEUM

    Directory of Open Access Journals (Sweden)

    Leonid Aleksandrovich Bobrov

    2015-10-01

    Full Text Available The article describes battle axes, stored in the Omsk State Museum of Regional History. One of them has a blade of oblong-triangular shape, and the other has oblong-trapezoidal shape. The surface of the strikers is decorated with floral and geometric ornament made in the technique of silver notches on metal. Axe handles are reinforced with iron «cuts» and straps.Experts of the Museum identified these types of shockslashing weapons as Kazakh «battle axes aibalta» and suggested possible dates: late XVIII– early XIX century, or the XIX century. The analysis of the structure and system of the decoration helps to clarify the dating and attribution of the weapons. It is stated that the axes were indeed made by Kazakh gunsmiths, however, the shape of the blade and slightly curved blade allows to define them as axes not «aibalta» (the distinctive feature of which was a lunar C-shaped blade, but as battle axes «balta».Their production may be dated back to the XVIII– XIX centuries. In the complex of shock-chopping weapons of Kazakh nomads, battle axes «balta» had an intermediate position between narrow-bladed axes «shakan» and axes «aibalta». Experimental tests show that strikes of the «balta» type axe had a powerful shock-crushing effect. They presented a significant threat for enemy soldiers who did not have protective arms or were dressed in quilted cotton suit armour.Strikes of «balta» could not break metal armor, but could injure a body and crush bones of an enemy warrior. Along with the high functional characteristics of the axes of the Museum, they have bright decorative design. For example, the axe No. 3659 with its decorative patterns can be compared with the best samples of Kazakh shockchopping weapons stored in the Museum collections of the Russian Federation and the Republic of Kazakhstan.

  8. The Early Devonian eurypterid Grossopterus overathi (Gross, 1933 from Overath, Germany

    Directory of Open Access Journals (Sweden)

    J. A. Dunlop

    2002-01-01

    Full Text Available The holotype and only known specimen of the eurypterid (Chelicerata: Eurypterida Grossopterus overathi (Gross, 1933 from the Early Devonian (Siegennian of Overath, north-west Germany is redescribed. Based on comparisons with other eurypterid taxa we interpret G. overathi as having a well-preserved type B genital appendage, which exhibits two apomorphic character states: (1 a furca fused into a single, spatulate plate and (2 marginal serrations near the distal end of the appendage. Grossopterus is assigned to the family Hughmilleriidae, but its carapace resembles that of the larger Slimonia acuminata (Salter, 1856 (Slimoniidae. A provisional phylogenetic analysis resolves Grossopterus as the sister group of (Slimonia + Pterygotoidea. The large pterygotids, in particular, have been suggested as significant predators on early vertebrates and hypotheses about eurypterid-fish co-evolution are reviewed, in particular Romer's proposal that dermal armour in fish evolved in response to eurypterid predation. Der Holotyp – das einzig bekannte Exemplar – des Eurypteriden (Chelicerata: Eurypterida Grossopterus overathi (Gross, 1933 aus dem frühen Devon (Siegennian von Overath im nordwestlichen Deutschland wird wieder beschrieben. Basierend auf Vergleichen mit anderen Eurypteriden-Taxa interpretieren wir G. overathi als Träger eines Typ B-Anhanges, wobei zwei apomorphe Merkmalszustände vorliegen: (1 die Furca ist zu einer einzigen, spatelförmigen Platte verschmolzen, und (2 der Seitenrand nahe des distalen Endes des Genitalanhanges ist gezähnt. Grossopterus wird zur Familie der Hughmilleriidae gestellt, aber der prosomale Dorsalschild ähnelt der größeren Slimonia acuminata (Salter, 1856 (Slimoniidae. Eine vorläufige phylogenetische Analyse zeigt Grossopterus als Schwesteruppe von (Slimonia + Pterygotoidea auf. Besonders die großen Pterygotiden wurden als signifikante Prädatoren von frühen Vertebraten gehandelt, und Hypothesen zur Eurypteriden

  9. A new method of combined techniques for characterization and monitoring of seawater interface in an alluvial aquifer

    Science.gov (United States)

    Folch, Albert; del Val, Laura; Luquot, Linda; Martínez, Laura; Bellmunt, Fabian; Le Lay, Hugo; Rodellas, Valentí; Ferrer, Núria; Fernández, Sheila; Ledo, Juanjo; Pezard, Philippe; Bour, Olivier; Queralt, Pilar; Marcuello, Alex; García-Orellana, Jordi; Saaltink, Maarten; Vázquez-Suñé, Enric; Carrera, Jesús

    2016-04-01

    Understand the dynamics of the fresh-salt water interface in aquifers is a key issue to comprehend mixing process and to quantity the discharge of nutrients in to coastal areas. In order to go beyond the current knowledge in this issue an experimental site has been set up at the alluvial aquifer Riera Argentona (Barcelona - Spain). The site comprises 16 shallow piezometers installed between 30 and 90 m from the seashore, with depths ranging between 15 and 25 meters. The seawater interface is being monitored using several techniques, the combination of which will help us to understand the spatial and temporal behaviour of the mixing zone and the geochemical processes occurring there. Specially the deepest piezometers are equipped with electrodes in order to perform cross-hole electrical resistivity tomography (CHERT). In addition, all piezometers are also equipped with Fiber Optic cable to perform distributed temperature measurements. Two single steel armoured fibre optic cable lines of around 600m length were installed in all boreholes. The objective is to use the cable both as passive and active temperature sensor. The first is being done for the continuous monitoring of temperature whereas; the second provides a higher temperature resolution used to monitor field experiments. Periodic CHERT measurements are carried out between the piezometer equipped with electrodes, resulting in parallel and perpendicular vertical cross sections of the site resistivity. The position of the fresh-salt water interface can be identified due to the resistivity contrast between the saline and fresh water. Preliminary results of periodic distributed temperature measurements will be also be used to monitor the position of the mixing zone thanks to the contrast and seasonal temperature changes. Periodic down-hole EC profiles will be used to validate the method. Acknowledgements This work was funded by the projects CGL2013-48869-C2-1 y CGL2013-48869-C2-2-R of the Spanish Government. We

  10. Burns and military clothing.

    Science.gov (United States)

    McLean, A D

    2001-02-01

    Burn injury is a ubiquitous threat in the military environment. The risks during combat are well recognised, but the handling of fuel, oil, munitions and other hot or flammable materials during peacetime deployment and training also imposes an inherent risk of accidental burn injury. Over the last hundred years, the burn threat in combat has ranged from nuclear weapons to small shoulder-launched missiles. Materials such as napalm and white phosphorus plainly present a risk of burn, but the threat extends to encompass personnel in vehicles attacked by anti-armour weapons, large missiles, fuel-air explosives and detonations/conflagrations on weapons platforms such as ships. Large numbers of burn casualties were caused at Pearl Harbor, in Hiroshima and Nagasaki, Vietnam, during the Arab/Israeli Wars and in the Falkland Islands conflict. The threat from burns is unlikely to diminish, indeed new developments in weapons seek to exploit the vulnerability of the serviceman and servicewoman to burns. Clothing can be a barrier to some types of burn--both inherently in the properties of the material, but also by trapping air between clothing layers. Conversely, ignition of the clothing may exacerbate a burn. There is hearsay that burnt clothing products within a wound may complicate the clinical management, or that materials that melt (thermoplastic materials) should not be worn if there is a burn threat. This paper explores the incidence of burn injury, the mechanisms of heat transfer to bare skin and skin covered by materials, and the published evidence for the complication of wound management by materials. Even light-weight combat clothing can offer significant protection to skin from short duration flash burns; the most vulnerable areas are the parts of the body not covered--face and hands. Multilayered combat clothing can offer significant protection for short periods from engulfment by flames; lightweight tropical wear with few layers offers little protection. Under

  11. The need to go beyond analysis in making risk-based decisions

    International Nuclear Information System (INIS)

    As a physicist, I prefer the R = P x C, with the inclusion of a risk magnifier when appropriate. However, I also accept this is inadequate. For risk-based decisions to be acceptable in a democratic society, there must be widespread agreement on the criteria to be used, the process by which the decision is reached, and the linkage between the criteria and the decision. These demand a transparent process. Armour wrote: 'To date, efforts directed toward facility siting conflicts have focused almost exclusively on the 'public acceptance' factor (and neglected the legitimacy of the process] - the sad reality is that these strategies have not been all that effective. Moreover, given that the underlying motivation is to 'gain public acceptance' such strategies have often worsened the facility siting problems when used by proponents who were unable, in appearance or in fact, to tread the fine line between manipulating public opinion and liberating it ... the issue of the legitimacy of the decision making process had tended to be taken for granted. Generally speaking, policy makers have failed to seriously question and have not responded well to others who have dared to question the established roles and principles of our conventional processes of decision making.' Finally, acceptance also requires agreement that the issues to be decided are the appropriate issues. Often the decision-makers concentrate on issues that are not the ones the public views as the most important. Sometimes it is because the public wants other alternatives examined. Sometimes it is because the public does not accept the necessity to decide now. And sometimes it is because the public does not trust those who have assumed responsibility for making the decision. The analytic community has grown in size and skill over the last 20 years. The science community has produced a better understanding of health effects and exposure pathways. The engineering community has designed safer systems. However, the

  12. The preliminary data on the Aeronian (Silurian) machaerids from Lithuania (Baltic Basin)

    Science.gov (United States)

    Radzevičius, S.; Ekleris, A.

    2012-04-01

    Machaerids are stem-Lophotrochozoans, closely related to the Annelids, and known from the Early Ordovician to Middle Permian. Machaerids is a group of worm-like benthic marine, bilaterally symmetrical, armoured invertebrate. Their body is covered by an external scleritome. The scleritome is imbricated of longitudinally arranged series of plates or sclerites. Completely articulated specimens of machaeridians are very rare, yet the systematic position of machaerids is controversial. Machaeridians had been assigned to different groups, such as barnacles, mollusks, echinoderms and annelids. The latter is prevailing, however their exact place within the annelids still remains unresolved. New findings of disarticulated Silurian machaerids have been recorded in western Lithuania, Geniai-1 core. This well has been drilled with exploration purposes regarding the Cambrian oil reservoir; therefore the biggest part of the Silurian core has not been collected. The exceptions are some parts of the Llandovery and Ludlow, which have partially recovered well core, but the identification of the precise stratigraphical position is complicated. Disarticulated sclerites of machaeridians have been found at the 1756.4 m depth, in the argillite, together with some graptolites and brachiopods. Several rhabdosome fragments of Normalograptus scalaris (Hisinger) were found together with the machaenid sclerites as well. N. scalaris has wide biostratigraphical distribution from the Rhudanian to the lower part of Telychian, which comprises the convolutus - triangulates graptolite biozones, corresponding to the 1756.8 - 1756 m depth. Convolutus - triangulates biozones represent Aeronian, and the machaeridian sclerites come from this interval, together with the Jonsea grayi (Davidson) brachiopod shells, which are very common and correspond to the BA 5-6 benthic assemblage, as well as do the graptolites found together. In previous studies, two orders of machaerids have been recognized: the

  13. Finite Element Based Design Optimization of WENDELSTEIN 7-X Divertor Targets

    International Nuclear Information System (INIS)

    In the fusion experiment WENDELSTEIN 7-X divertor plasma facing components have to withstand severe loading conditions. In general thermally induced mechanical stressing turns out to be most critical with respect to life time predictions of the component. In the specific case flat tiles of CFC grade NB31 are joined to the precipitation hardened CuCrZr heat sink by employing an active metal cast (AMC)-Cu as an interlayer between CFC and CuCrZr. Residual stresses resulting from the manufacturing process act as initial stresses in the subsequent operational heat flux loading. For the latter loading regime these stresses intrinsically are generated due to the large contrast in the CTE for CFC and Cu. Different design variants of those CFC flat tile armoured target elements have been analysed via the finite element package ABAQUS aiming at derivation of an optimized component design. The numerical study comprises variants with different degrees of tessellation of the CFC flat tile section, orientation of the CFC, lamellar design of the AMC-interlayer, and different designs of the cooling channels. The thermo-mechanical material characteristics are accounted for the finite element models with elastic-plastic properties being assigned to the metallic sections CuCrZr and AMC-Cu, respectively, and orthotropic nonlinear-elastic properties being used to the CFC section. The latter has been realized in form of a user-defined material subroutine that is used at the integration point level of the finite element model. In particular, twelve scalar-type damage parameters obeying their own evolution equations with respect to the loading history account for specific stress-strain relationships in the three principal material directions and planes with six damage parameters being used for normal loading under tensile and compressive stress states, respectively, and six parameters being used for shear loading. For the aim of model verification calculated surface temperatures, global

  14. Ballistic behavior of boron carbide reinforced AA7075 aluminium alloy using friction stir processing–An experimental study and analytical approach

    Institute of Scientific and Technical Information of China (English)

    I. SUDHAKAR; G. MADHUSUDHAN REDDY; K. SRINIVASA RAO

    2016-01-01

    High strength-to-weight ratio of non-ferrous alloys, such as aluminium, magnesium and titanium alloys, are considered to be possible replacement of widely accepted steels in transportation and automobile sectors. Among these alloys, magnesium is self explosive and titanium is costlier, and aluminium is most likely to replace steels. Application of aluminium or its alloys is also thought of as an appropriate replacement in defence field, especially to enhance the easiness in mobility of combat vehicles while maintaining the same standard as that of conventional armour grade steels. Hence most of the investigations have been confined to aluminium or its alloys as base material and open an era of developing the newer composite materials to address the major limitation, i.e. tribological properties. The surface composites can be fabricated by incorporating the ceramic carbides like silicon carbide, carbides of transition metals and oxides of aluminium using surface modification techniques, such as high energy laser melt treatment, high energy electron beam irradiation and thermal spray process which are based on fusion route. These techniques yield the fusion related problems, such as interfacial reaction, pin holes, shrinkage cavities or voids and other casting related defects, and pave the way to need of an efficient technique which must be based on solid state. Recently developed friction stir processing technique was used in the present investigation for surface modification of AA7075 aluminum alloy, which is an alternative to steels. In the present investigation, 160μm sized boron carbide powder was procured and was reduced to 60μm and 30μm using high energy ball mill. Subsequently these powders were used to fabricate the surface composites using friction stir processing. Ballistic performance testing as per the military standard (JIS.0108.01) was carried out. In the present work, an analytical method of predicting the ballistic behavior of surface composites

  15. Technology Programme

    Energy Technology Data Exchange (ETDEWEB)

    Batistoni, Paola; De Marco, Francesco; Pieroni, Leonardo (ed.)

    2005-07-01

    The technology activities carried out by the Euratom-ENEA Association in the framework of the European Fusion Development Agreement concern the Next Step (International Thermonuclear Experimental Reactor - ITER), the Long-Term Programme (breeder blanket, materials, International Fusion Materials Irradiation Facility - IFMIF), Power Plant Conceptual Studies and Socio-Economic Studies. The Underlying Technology Programme was set up to complement the fusion activities as well to develop technologies with a wider range of interest. The Technology Programme mainly involves staff from the Frascati laboratories of the Fusion Technical and Scientific Unit and from the Brasimone laboratories of the Advanced Physics Technologies Unit. Other ENEA units also provide valuable contributions to the programme. ENEA is heavily engaged in component development/testing and in design and safety activities for the European Fusion Technology Programme. Although the work documented in the following covers a large range of topics that differ considerably because they concern the development of extremely complex systems, the high level of integration and coordination ensures the capability to cover the fusion system as a whole. In 2004 the most significant testing activities concerned the ITER primary beryllium-coated first wall. In the field of high-heat-flux components, an important achievement was the qualification of the process for depositing a copper liner on carbon fibre composite (CFC) hollow tiles. This new process, pre-brazed casting (PBC), allows the hot radial pressing (HRP) joining procedure to be used also for CFC-based armour monoblock divertor components. The PBC and HRP processes are candidates for the construction of the ITER divertor. In the materials field an important milestone was the commissioning of a new facility for chemical vapour infiltration/deposition, used for optimising silicon carbide composite (SiCf/SiC) components. Eight patents were deposited during 2004

  16. Heterogeneous microchemistry between CdSO4 and CaCO3 particles under humidity and liquid water

    International Nuclear Information System (INIS)

    Highlights: ► Raman analysis of chemical reactions between CdSO4 and CaCO3 particles. ► Under humid air no changes of morphology and chemical composition were observed. ► Condensation of liquid water generates an insoluble CdCO3 layer on CaCO3 surface. ► Addition of water previously equilibrated with CaCO3 generates CdCO3 and CaSO4. -- Abstract: Laboratory experiments using in situ Raman imaging combined with ex situ TOF-S-SIMS demonstrate the behavior of CdSO4·8/3H2O microparticles in contact with {101¯4} CaCO3 (calcite) surface under three different experimental conditions representative of unpolluted atmosphere. The contact of CdSO4·8/3H2O particles with CaCO3 surface in humid air (RH ∼ 40–80%) does not induce any chemical reaction. In contrast, the condensation of a water drop on CdSO4·8/3H2O/CaCO3 interface causes the free dissolution of CdSO4·8/3H2O particle in the drop. A CdSO4·8/3H2O microcrystal is reformed after gentle drying with a CdSO4·H2O coating of the CaCO3 surface. The TOF-S-SIMS image of the CaCO3 surface provides evidence of a thin layer corresponding probably to insoluble coating of CdCO3 (otavite) or CdxCa1−xCO3 solid solution at the liquid–solid interface. This layer armours the CaCO3 from further dissolution and stops the reaction. The deposition of CdSO4·8/3H2O particle in water drop previously in contact with CaCO3 for a long time generates CdCO3 small rhombohedral crystals while gentle drying provokes the crystallization of bar shape crystals of CaSO4·2H2O (gypsum). These laboratory results provide valuable chemical prediction for a possible fate of cadmium rich particles emitted in the atmosphere and thus, can contribute to realistic assessment of human exposure to Cd hazard

  17. Microbial activity in argillite waste storage cells for the deep geological disposal of French bituminous medium activity long lived nuclear waste: Impact on redox reaction kinetics and potential

    Science.gov (United States)

    Albrecht, A.; Leone, L.; Charlet, L.

    2009-04-01

    Micro-organisms are ubiquitous and display remarkable capabilities to adapt and survive in the most extreme environmental conditions. It has been recognized that microorganisms can survive in nuclear waste disposal facilities if the required major (P, N, K) and trace elements, a carbon and energy source as well as water are present. The space constraint is of particular interest as it has been shown that bacteria do not prosper in compacted clay. An evaluation of the different types of French medium and high level waste, in a clay-rich host rock storage environment at a depth between 500 and 600 m, has shown that the bituminous waste is the most likely candidate to accommodate significant microbial activity. The waste consists of a mixture of bitumen (source of bio-available organic matter and H2 as a consequence of its degradation and radiolysis) and nitrates and sulphates kept in a stainless steel container. The assumption, that microbes only have an impact on reaction kinetics needs to be reassessed in the case where nitrates and sulphates are present since both are known not to react at low temperatures without bacterial catalysis. The additional impact of both oxy-anions and their reduced species on redox conditions, radionuclide speciation and mobility gives this evaluation their particular relevance. Storage architecture proposes four primary waste containers positioned into armoured cement over packs and placed with others into the waste storage cell itself composed of a cement mantle enforcing the argillite host rock, the latter being characterized by an excavation damaged zone constricted both in space and in time and a pristine part of 60 m thickness. Bacterial activity within the waste and within the pristine argillite is disregarded because of the low water activity (low mobility of critical RN, • increased retardation of mobile RN in biofilms (i.e. adsorption on microbial cell surfaces and products of possible biomineralization); complexation by

  18. Hydrogen in tungsten as plasma-facing material

    International Nuclear Information System (INIS)

    Materials facing plasmas in fusion experiments and future reactors are loaded with high fluxes (1020-1024 m-2 s-1) of H, D and T fuel particles at energies ranging from a few eV to keV. In this respect, the evolution of the radioactive T inventory in the first wall, the permeation of T through the armour into the coolant and the thermo-mechanical stability after long-term exposure are key parameters determining the applicability of a first wall material. Tungsten exhibits fast hydrogen diffusion, but an extremely low solubility limit. Due to the fast diffusion of hydrogen and the short ion range, most of the incident ions will quickly reach the surface and recycle into the plasma chamber. For steady-state operation the solute hydrogen for the typical fusion reactor geometry and wall conditions can reach an inventory of about 1 kg. However, in short-pulse operation typical of ITER, solute hydrogen will diffuse out after each pulse and the remaining inventory will consist of hydrogen trapped in lattice defects, such as dislocations, grain boundaries and irradiation-induced traps. In high-flux areas the hydrogen energies are too low to create displacement damage. However, under these conditions the solubility limit will be exceeded within the ion range and the formation of gas bubbles and stress-induced damage occurs. In addition, simultaneous neutron fluxes from the nuclear fusion reaction D(T,n)α will lead to damage in the materials and produce trapping sites for diffusing hydrogen atoms throughout the bulk. The formation and diffusive filling of these different traps will determine the evolution of the retained T inventory. This paper will concentrate on experimental evidence for the influence different trapping sites have on the hydrogen inventory in W as studied in ion beam experiments and low-temperature plasmas. Based on the extensive experimental data, models are validated and applied to estimate the contribution of different traps to the tritium inventory in

  19. The tactical development of Achaemenid cavalry

    Directory of Open Access Journals (Sweden)

    Nefedkin, Alexander K.

    2006-12-01

    Full Text Available

    In the 6th and first half of the 5th century BC, Persian horsemen were armed with bows and javelins, and fought as a light cavalry. In the second half of the 5th century in the western regions of the Persian empire there was an increase in heavily-armoured cavalry, armed with the spears (palta for thrusting and throwing. I propose that this evolution is connected with the long wars against the Greeks and the deterioration of the morale quality of Persian warriors. The attempt of the last Persian king Darius III to re-arm his horsemen with lances to fight the Macedonian Companions did not succeed in saving the Achaemenid empire from collapse.



    En el siglo VI y la primera mitad del siglo V A. C. los caballeros persianos fueron armados con arcos y jabalinas y luchaban como caballeria ligera. En la segunda mitad del siglo V A.C. en las regiones occidentales del Imperio Persa se extienden caballeros de armadura pesada, armados con lanzas (palta, aunque la mayor parte de caballeria estaba formada con armados ligeramente. Segun mi opinion, estos cambios en caballeria persiana eston relacionados con la lenta guerra contra los griegos y tambien con empeoramiento de completacion de caballeria local. El intento de Dario III de rearmar a sus caballeros con las lanzas largas para luchar con exito con caballeria macedonica, fracaso por causa de caida del Imperio Aquemenido.

  20. Scour protection for wind turbine foundations on highly erodible sea bottom

    Energy Technology Data Exchange (ETDEWEB)

    Ottesen Hansen, N.E.

    2002-12-01

    Scour around offshore structures is well known. It is caused by the strong eddy formation at the base of the structures protruding from the sea bottom. The strong vortices result in an amplified effective shear stress working on the sea bottom surface adjacent to the structure. When the surrounding sea bottom is lowered the scour protection will end up being a cap on a small hill and when the slopes are getting too steep the scour protection will roll or slide down the sides. It will loose its cohesion and therefore its integrity. This will take place irrespective of the type of scour protection material and the type of scour protection. This report describes scour protections, which can deal with this particular problem. Such a scour protection must be able to sustain the following loads: Be able to follow the lowering of the seabed on its way down; Be resistant to edge scour (scour around the perimeter of the scour protection). The installation of scour protection is not straightforward because the developed scour hole may be very uneven. It will be highly impractical to survey the hole although it can be done. There will be power cables etc. obstructing for ROV's or instrumented backhoe arms. Therefore the recommended method is to assume that the scour hole is developed and to place the scour protection material evenly around the foundation. In practice this is done by fall pipes positioned from a barge or by an instrumented backhoe. The procedure will be as follows: The outline of the scour hole is surveyed by a ROV (eye ball) and the status of the power cables are investigated; If the tie-in of the power cables are hanging as free spans, material shall be dumped on these spans in order to cover them. This material shall have a size, which will not be harmful to the cable during a dumping; Alternatively the tie-in takes place through an armoured flex-pipe that can sustain the impact from the stone dumping. Hence, in this case the stone dumping can commence

  1. Overview of the laser activities at Rheinmetall Waffe Munition

    Science.gov (United States)

    Ludewigt, Klaus; Riesbeck, Thomas; Schünemann, B.; Graf, A.; Jung, Markus; Schreiber, Th.; Eberhardt, Ramona; Tünnermann, A.

    2012-11-01

    The paper will give an overview over the laser weapon activities at RWM (Rheinmetall Waffe Munition) over the last years. Starting from the actual scenarios for laser weapon applications as: CRAM (Counter Rocket Artillery Mortar), Air Defence and UXO (unexploded ordnance) clearing. The basic requirements of a future laser weapon as beam diameter, beam quality, tracking capability, adaptive optics were deduced. For the UXO scenario a mobile directed energy laser demonstrator for humanitarian mine and UXO clearing based on fiber lasers is presented. Based on the parameters the system concept including the cooling system, power supply and the integration into the armoured vehicle TM 170 are explained. The contribution show first experiments of UXO and IED clearing. Different technical approaches to achieve laser power in the 100 kW regime combined with very good beam quality are discussed to fulfil the requirements of the CRAM and Air Defence scenario. Spectral coupling and the beam superimposing both are performed by Rheinmetall Waffe Munition. At the spectral coupling the basic technology parameters for the fiber laser and the dielectric grating as the latest results were put into context with the power levels reached at other groups. For the beam super imposing technology the basic experiments regarding the tracking capability and compensation of the atmosphere on the test range at Unterlüß will be explained. A generic 10 kW Laser Weapon Demonstrator based on 2 Laser Weapon Modules (LWM) from RWM each 5 kW fiber Laser with beam forming and tracking integrate by the team of RWM and RAD (Rheinmetall Air Defense) into a Ground based Air Defend system consisting of Skyguard and Millenium turret are presented. The flight path of the UAV within the valley of the life firing range at Ochsenboden Switzerland is shown. Selected results of the successful tests against UAV's are presented. It shows the capability of the generic 10 kW Laser Weapon Demonstrator to track and

  2. Check dams effects on sediment transport in steep slope flume

    Science.gov (United States)

    Piton, Guillaume; Recking, Alain

    2014-05-01

    Depending on many influences (geology, relief, hydrology, land use, etc.) some mountainous watershed are prone to cause casualties and facilities damages. Large amounts of sediments episodically released by torrents are often the biggest problem in torrent related hazard mitigation. Series of transversal structures as check dams and ground sills are often used in the panel of risk mitigation technics. A large literature exits on check dams and it mainly concerns engineering design, e.g. toe scouring, stability stress diagram, changes in upper and lower reaches equilibrium slopes. Check dams in steep slope rivers constitute fixed points in the bed profile and prevent general bed incision. However their influence on sediment transport once they are filled is not yet clear. Two flume test campaigns, synthetize in Table 1, were performed to investigate this question: Table 1 : experiment plan Run (duration) Ref1 (50h)CD1a (30h)CD1b (30h)Ref2 (92h)CD2 (18h) Solid feeding discharge (g.s^-1) 44 44 44 60 60 Number of check dams none 1 3 none 2 A nearly 5-m-long, 10-cm-wide and 12%-steep flume was used. The water discharge was set to 0,55 l/s in all runs. A mixture of poorly sorted natural sediments with diameters between 0.8 and 40 mm was used. An open solid-discharge-feeding circuit kept the inlet sediment flux constant during all experiments. As both feeding rates did not present variation, changes in outlet solid discharge were assumed to be due to bed variations in the bed storage. We observed strong fluctuations of solid flux and slope in each reaches of all runs between: (i) steep aggradating armoured bed and (ii) less steep and finer bed releasing bedload sheets during erosion events and inducing bedload pulses. All experiments showed consistent results: transported volume associated with erosion event decreased with the length between two subsequent check dams. Solid transversal structures shorten the upstream erosion-propagation and avoid downstream change in the

  3. Energy-resolved photoemission studies of Be-containing surfaces for fusion

    International Nuclear Information System (INIS)

    Fusion research aims at the exploitation of the deuterium-tritium reaction for energy production. Next step on the roadmap is the construction of the experimental reactor ITER. The three elements beryllium, carbon and tungsten are to be used as armour materials for the vacuum vessel. After erosion due to plasma processes, these materials are transported and redeposited together with plasma impurities like oxygen from surface oxides. This leads to the formation of compounds by chemical reactions and diffusive processes, induced both by elevated temperatures and implantation of energetic particles. Due to the complexity of the induced surface processes, a method is required which is capable of both qualitative and quantitative analysis of the involved chemical species. X-ray photoelectron spectroscopy (XPS) provides the chemical analysis. Since diffusive processes play an important role in solid-state reactions, a depth-resolved method is required. In this work, energy-resolved XPS using synchrotron radiation with variable photon energies is extended towards a quantitative depth-resolved analysis. For the quantitative analysis a new model is derived which calculates the depth-resolved composition and the respective composition-dependent electron inelastic mean free path in a self-consistent way. Input is the XPS data which is normalized with all parameters influencing the photoelectron intensities. This fully quantitative model is applied to describe the interaction of energetic oxygen ions with the beryllium-tungsten alloy Be2W. Oxygen ions from the plasma are able to interact with plasma facing materials. Formation of Be2W is to be expected at the first wall and in the divertor region of ITER. Irradiation of this alloy leads to its decompositions. After decomposition, formation of beryllium oxide BeO is preferred compared to formation of tungsten oxides. Heating to 600K leads to chemical reduction of tungsten oxides. Metallic Be acts as reduction agent. Oxygen

  4. Application of tungsten-fibre-reinforced copper matrix composites to a high-heat-flux component: A design study by dual scale finite element analysis

    International Nuclear Information System (INIS)

    According to the European Power Plant Conceptual Study, actively cooled tungsten mono-block is one of the divertor design options for fusion reactors. In this study the coolant tube acts as a heat sink and the tungsten block as plasma-facing armour. A key material issue here is how to achieve high temperature strength and high heat conductivity of the heat sink tube simultaneously. Copper matrix composite reinforced with continuous strong fibres has been considered as a candidate material for heat sink of high-heat-flux components. Refractory tungsten wire is a promising reinforcement material due to its high strength, winding flexibility and good interfacial wetting with copper. We studied the applicability of tungsten-fibre-reinforced copper matrix composite heat sink tubes for the tungsten mono-block divertor by means of dual-scale finite element analysis. Thermo-elasto-plastic micro-mechanics homogenisation technique was applied. A heat flux of 15 MW/m2 with cooling water temperature of 320 oC was considered. Effective stress-free temperature was assumed to be 500 oC. Between the tungsten block and the composite heat sink tube interlayer (1 mm thick) of soft Cu was inserted. The finite element analysis yields the following results: The predicted maximum temperature at steady state is 1223 oC at the surface and 562 oC at the interface between tube and copper layer. On the macroscopic scale, residual stress is generated during fabrication due to differences in thermal expansion coefficients of the materials. Strong compressive stress occurs in the tungsten block around the tube while weak tensile stress is present in the interlayer. The local and global probability of brittle failure of the tungsten block was also estimated using the probabilistic failure theories. The thermal stresses are significantly decreased upon subsequent heat flux loading. Resolving the composite stress on microscopic scale yields a maximum fibre axial stress of 3000 MPa after fabrication

  5. Vegetated Riprap Installation Techniques for Steambank Protection, Fish and Wildlife Habitat Creation

    Science.gov (United States)

    Raymond, Pierre

    2014-05-01

    Vegetated riprap is a cost effective alternative to conventional riprap erosion protection. Terra Erosion Control has experimented with the vegetation of riprap over the past ten years. As a result we have adapted a technique that can successfully establish vegetation during the installation of riprap structures. This presentation will demonstrate innovative ways of installing vegetated riprap for the protection of access roads on industrial sites and urban infrastructure such as storm water outfalls, bridge approaches and pedestrian pathways within public areas. This vegetation will provide additional bank protection, soften the rock appearance and enhance fish, wildlife and urban habitat along the shoreline. Vegetated riprap incorporates a combination of rock and native vegetation in the form of live cuttings. These are planted in conjunction with the placement of rock used to armour the banks of watercourses. Establishment of native vegetation will improve fish habitat by creating shade, cover and an input of small organic debris to stream banks. In most cases it will negate the need for the regulator (Canadian Department of Fisheries and Oceans) to require habitat alteration compensation. It will also provide added bank protection through the development of root mass. Adding vegetation to riprap provides a softer, more natural appearance to the installed rocks. This presentation will detail the processes involved in the installation of vegetated riprap such as the harvesting and soaking of live material, site preparation of the stream bank, placement of riprap in conjunction with live material and the use of burlap/coir fabric and soil amendments. It will also discuss the innovative method of using wooden boards to protect live cuttings during construction and to direct precipitation and/or irrigation water to the root zone during the establishment phase of the vegetation. These boards will eventually biodegrade within the rock. This approach was applied over

  6. Radiological conditions in areas of Kuwait with residues of depleted uranium. Report by an international group of experts

    International Nuclear Information System (INIS)

    Depleted uranium (DU) is one of the by-products of uranium enrichment and, like any other uranium compound, has both chemical and radiological toxicity; it is mildly radioactive, having about 60% of the activity of natural uranium. DU has had a wide range of peaceful applications, such as the provision of radiation shielding for medical sources or as counterweights in aeroplanes. DU is also used for heavy tank armour and, owing to its high density and high melting point and its property of becoming 'sharper' as it penetrates armour plating, in anti-tank munitions and missiles. The 1991 Gulf War was the first conflict in which DU munitions were used extensively. In view of the concerns raised about the possible link between human exposure to ionizing radiation from DU and harmful biological effects, the Government of Kuwait, in February 2001, requested the IAEA to conduct surveys at and assessments of a number of specified locations. The aim of this work was to inform the Government of Kuwait and the public of the possible radiological conditions arising owing to DU residues at these sites. The IAEA accepted the request for a radiological assessment under its unique statutory functions within the United Nations system, namely: (1) to establish standards of safety for protection against radiation exposure; and (2) to provide for the application of these standards. In 1996 the IAEA, in cosponsorship with other relevant organizations in the United Nations system, established the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. These standards are fully applicable to exposure to all forms of ionizing radiation, including exposure to any uranium radionuclides in general and, in particular, to DU. In the past, a number of evaluations of the environmental and health impact of DU munitions have been performed by national and international organizations. This report constitutes the first comprehensive

  7. Isotopes in Australian environmental analysis

    International Nuclear Information System (INIS)

    Full text: ANSTO Environment is playing a pioneering role in developing new methods for monitoring adherence to the Nuclear Non-proliferation Treaty. Working with the IAEA Department of Safeguards, new analytical procedures have been developed to assist with their environmental monitoring programme. Signatures of nuclear activities, in the form of trace amounts of radioisotopes in environmental samples, can be used to identify undeclared nuclear facilities or undeclared activities at declared facilities. At ANSTO we have developed the use of Accelerator Mass Spectrometry (AMS) for analysis of 236U in environmental samples. 236U is a sensitive indicator of irradiated uranium. AMS is also used to detect the long- lived fission product 129I at extremely low levels. The presence of 129I can be a signature of reprocessing. ANSTO performs analyses of these radioisotopes as an accredited member of the IAEA Safeguards network of analytical laboratories. Australian soldiers on duty in the Gulf risk possible exposure to depleted uranium. Depleted uranium is the uranium that is left after most of the radioactive isotopes are removed for nuclear fuel. Due to its high density, it is the ideal material for use in armour-piercing ammunition and in armour for fighting vehicles. However, like any heavy metal, it is toxic in high doses. Depleted uranium enters the body through inhalation of the dust- like particles, ingestion of contaminated food or through wounds. At ANSTO, a sensitive analytical technique based on isotope dilution and inductively coupled plasma mass spectrometry (ICP-MS) was used to detect depleted uranium in urine samples. By addition of known quantities of 236U (isotope dilution) to the urine samples and measuring the relative abundances of different isotopes (236U, 235U and 238U) of uranium by ICP-MS, we are able to quantify (quantification limit of 20 ng/L) and distinguish between natural and depleted uranium. In Australia, there are legislative limits on the

  8. Los hallazgos de armas en los campamentos romanos alrededor de Numancia

    Directory of Open Access Journals (Sweden)

    Luik, Martin

    2010-12-01

    Full Text Available This paper provides an overview of the finds of arms and armour from the Roman camps around Numantia, i.e. the circumvallation surrounding the oppidum of Renieblas. Virtually all of the material presented was recovered during the 1906-1912 excavations led by Adolf Schulten. Since the conclusion of these research campaigns, there have only been isolated surface finds. The entire corpus of finds was drawn and - in part - photographed. The material was furher analysed and published as a monograph (Luik 2002. A particularly interesting result of this analysis is that there are relatively few defensive items such as body-armour or shield bosses. Offensive weaponry, and ranged weapons in particular, on the other hand, are frequent and include spearheads, socketed as well as tanged pila and various types of arrow and bolt heads. Interestingly, there are few swords or daggers, and little associated equipment parts. All in all, the presented fi nds provide a unique insight into the equipment and arms of the Roman Army during the Late Republic. At the same time, the corpus of material discussed and presented provides new information regarding the internal structure of the Roman Army at the time.

    Este artículo pretende ofrecer un panorama general de los hallazgos de armas en los campamentos romanos alrededor de Numancia (línea de circunvalación en torno al oppidum, Renieblas. Los descubrimientos proceden casi en su totalidad de las excavaciones que se realizaron en los años 1906 a 1912 bajo la dirección de Adolf Schulten. Desde entonces, sólo hay que sumar algunos hallazgos aislados. La totalidad de los objetos ha sido documentada y sometida a un nuevo estudio científico y, finalmente, se presentó en forma de monografía en el año 2002 (Luik, 2002 con resumen español: 173-sq. En general, llama la atención la reducida proporción de armas defensivas (corazas de discos, cotas de malla, umbo de escudos. Por el contrario, las armas

  9. Bedload Yield and Sediment Budget In The Instrumented Catchment of The Rio Cordon (northeastern Italy)

    Science.gov (United States)

    Lenzi, M. A.

    Bedload yield may have large seasonal or interannual variations as a result of changes in sediment supply or sediment storage. Sediment supply along mountain rivers is strongly influenced by both drainage basin and channel processes. Drainage basin sediment inputs include hillslope, valley bottom and tributary channel sources that may be gradual (e.g. slope wash, average tributary inflows, soil creep) or abrupt (e.g. debris flow, rockfalls, tributary flash floods). These inputs may be seasonally driven (e.g. Wetzel, 1994) or aperiodic. The paper illustrates the results of 16 years research conducted on the Rio Cordon catchment (5 km2), where an experimental sta- tion has been operating for the integral and continuous automatic recording of water discharge and sediment transport (Lenzi et al., 1999). The device operates by separat- ing bedload from water discharge and fine sediment and subsequently measuring the two solid components. The 15 recorded floods (1986-2001) are grouped in two dis- tinct categories according to the bedload transport rates: SordinaryT and exceptionalT & cedil;floods (with return times exceeding 30-50 years). Supply-limited conditions of sed- iment transport prevail in the period 1986-1994, before the exceptional flash flood of September 14, 1994. During this cycle, bed armouring is the dominant sediment transport response: the amount of material of a given size range in transport is lim- ited by its availability and not by the competence of the flow. During the subsequent cycle 1995-2001, conditions of bedload transport change a lot given an increases of the sediment budget. An abrupt and aperiodic input of fine-medium grain size material occured to the main Rio Cordon stream during the snowmelt-induced flood of May 11, 2001, by means of a tributary mud flow contribution. This input influenced the bed- load transport by altering the proportion of the bed material which can be moved by the competent flow. The injection of these relatively

  10. Mineral displacement and -dissolution processes and their relevance to rock porosity and permeability in Rotliegend sandstones of the Altmark natural gas field (central Germany) - results from CO2 laboratory batch experiments

    Science.gov (United States)

    Pudlo, Dieter; Enzmann, Frieder; Heister, Katja; Werner, Lars; Ganzer, Leonhard; Reitenbach, Viktor; Henkel, Steven; Albrecht, Daniel; Gaupp, Reinhard

    2014-05-01

    The Rotliegend reservoir sandstones of the Altmark area (central Germany) comprise the second largest natural gas field of Europe. These sandstones were deposited on a playa-like continental platform with braided river systems, ephemeral lakes and aeolian dunes under semi-arid conditions. Some of the pristine, red coloured deposits suffered intensive late diagenetic alteration and are now preserved as bleached, high porous and permeable sandstones. To evaluate the relevance of distinct fluids and their fluid-rock alteration reactions on such bleaching processes we performed laboratory static batch experiments on the Altmark sandstones. These 4-6 week lasting runs were conducted with CO2 saturated synthetic brines under typical Altmark reservoir conditions (p= 20 MPa, T= 125°C). Thereby mineralogical, petrophysical and (hydro- and geo-) chemical rock features were maintained prior and after the experiments. Chemical data proved the dissolution of carbonate and sulphate minerals during the runs, whereas the variation in abundance of further elements was within the detection limit of analytical accuracy. However, FE-SEM investigations on used, evaporated brines reveal the presence of illite and chlorite minerals within a matrix of Ca-, Si-, Fe, Al-, Na- and S components (carbonate, anhydrite, albite and Fe-(hydr-) oxides ?). By porosity and relative permeability measurements an increase in both rock features was observed after the runs, indicating that mineral dissolution and/or (clay) fine migration/detachment occurred during the experiments. Mineral dissolution, especially of pore-filling cements (e.g. carbonate-, sulphate minerals) is also deduced by BET analysis, in determining the specific surface of the sandstones. The size of these reactive surfaces increased after the experiments, suggesting that after the dissolution of pore-filling cements, formerly armoured grain rimming clay cutans were exposed to potential migrating fluids. These findings are also

  11. The "Redynamisation of the Old Rhine", an international and interdisciplinary INTERREG project focused on for channel braiding restoration - 2009-2013

    Science.gov (United States)

    Piégay, H.; Béal, D.; Rollet, A.-J.; Arnaud, F.; Schmitt, L.

    2009-04-01

    The Upper Rhine between France and Germany has been heavily impacted by channelization for navigation and then by dams works during the last two centuries. Most of the flows are now conveyed in a canalized section, a minimum discharge been reserved in the old section, so called the "Old Rhine". Between Huningue and Neuf-Breisach (45 km), the longest disconnected section, engineering works induced simplification and stabilization of the channel pattern from a formerly braiding reach to a single incised channel (incision of 7m between 184 and 1920 before Kembs dam construction), hydrological modifications, channel bottom armouring due to bedload decrease, and thus ecological alterations. Within the framework of current research works on river restoration, a new international and interdisciplinary project on the Upper Rhine entitled "INTERREG IV - Redynamisation of the Old Rhine" began in early 2009 running for four years. The purpose of this project is to evaluate the feasibility of an important hydro-morphological and ecological restoration plan on the 45 km reach, expanding and gathering some independent national projects, by a closed partnership between French and German scientists, water management organisations and practitioners. The finality of the project is to provide possible prospective scenarios, in order to partially restore a braiding channel pattern on the Old Rhine channel, by promoting left bank erosion, channel enlargement and/or artificial sediment inputs. The Alsace Region will conduct the project administratively, and the scientific group will be coordinated by the University of Lyon (UMR 5600 CNRS). The study will involve historical, hydro-morphological, ecological and sociological parts. On one hand a historical approach, led by UMR 5600 and Electricité de France (EDF), will be necessary to understand long term channel changes since 1800 and thus to orientate restoration strategies. This task will be based on old maps, aerial photographs and

  12. Kazakhstan participation in International Experimental Reactor ITER Construction project. Work status and prospects

    International Nuclear Information System (INIS)

    Kazakhstan takes part in ITER project in partnership with Russian Federation since the year of 1994. At present the technical stage of the project is completed and ITER Council should take a decision on the site for international reactor. Four countries such as Canada, Japan, Spain and France have offered their territories for being used as site for launching ITER construction. ITER partners started preparing new international agreement that will cover activities on construction, operation and decommissioning of ITER. It will also include the list of research and experimental work that is conducted in support of ITER project. Kazakhstan has already made an important contribution into technical stage realization of ITER project due to scientific and technical researches conducted by National Nuclear Center, by Institute of Experimental and Theoretical Physics and by JSC 'Ulba Metallurgical plant' ('UMP'). Research activity carried out for the support of ITER project is performed in accordance with the following main trends: Tritium safety (permeability and retentin of hydrogen isotopes during in-pile irradiation in various structural materials, co-deposed layers and protective coatings); Verification of computer codes (LOCA type) loss of coolant accidents modeling in ITER reactor; Investigation of liquid metal blanket of thermonuclear reactor (tritium production in lithium containing eutectics Li17Pb83 and ceramics Li2TiO3, study of tritium permeability). At present the working group of ITER project participants started introducing proposals for cost distribution and for placing the orders on reactor construction. Further Kazakhstan participation in ITER project may be in manufacturing high-tech parts and assemblies from commercial grades of beryllium. They will be used for armouring the reactor first wall, for its thermal protection and for protection of superconductor's components for magnetic systems that are at JSC UMP'. Scientific and technical support of these

  13. 地基与海洋建筑物相互作用——以最近西班牙海岸线建筑物内部损坏为例%GROUND-MARITIME STRUCTURE INTERACTION.RECENT FAILURES IN INNER GRAVITY CONSTRUCTIONS ON THE SPANISH COASTLINE

    Institute of Scientific and Technical Information of China (English)

    Carlos Delgado; Dr Civil Engineer.; Professor M.P.U.

    2011-01-01

    海洋工程通常是一个细长的线.我们通常看到的仅仅是建筑物狭长的表面,而不分析支撑他们的大量水下材料.毋庸置疑,海底地基将承受来自于海洋的周期性和交替的静力以及变化的动力.外部和内部的海上工程均在复杂的环境中运行.固态颗粒(防波堤)可以吸入入射水流,并且通过颗粒之间的间距吸收海浪的能量.回流试图从固态颗粒中抽离物质,这样一个遵从太沙基原理的基于有效拉力和中性拉力之间的平衡建立起来.在某些情况下,防护层的液化已经造成了防波堤崩溃(Sines,葡萄牙,1978年2月).在其他情况下,虹吸作用或液化导致巨石(垂直的防波堤)毁坏或崩溃(新巴塞罗那港口,西班牙,2001年11月).结合复合设计工具的地基-作用力--结构相互作用的过程是一个复杂的分析,关于其研究刚刚开始.本文介绍了最近发生在西班牙的、由于地基失效导致的海上工程内部损坏的两个例子(马拉加,2004年7月,巴塞罗那,2007年1月),分析了其成因.%A maritime construction is usually a slender line in the ocean. It is usual to see just its narrow surface strip and not analyse the large amount of submerged material the latter is supporting. Without doubt,it is the ground to which a notable load is transmitted in an environment subjected to periodic, alternating stresses, dynamic forces which the sea's media constitute.Both an outer and inner maritime construction works in a complex fashion. A granular solid(breakwater) breathes with the incident wave flow,dissipating part of the wave energy between its gaps. The backflow tries to extract the different items from the solid block,setting a balance between effective and neutral tensions that follow Terzaghui's principle.On some occasions,fluidification of the armour layer has caused the breakwater to collapse( Sines,Portugal,February 1978 ). On others,siphoning or liquefaction of sand supporting

  14. Hydrogen-management in beyond design accident conditions in NPP Neckar 2

    International Nuclear Information System (INIS)

    Neckar 2 is a 1340 MWE 4-loop pressurized water reactor (PWR) of Siemens KONVOI type, located in the south of Germany. It was first connected to the grid in January 1989. Commercial operation started in April 1989. Task assignment: In Germany it was recommended by the Reactor Safety Commission (RSK) on December 17, 1997, to reequip passive autocatalytic recombiners for the controlling of the hydrogen problem. The removal of the hydrogen is an essential part which guarantees the integrity of the containment. The implementation of the recombiners is a further step for the decrease of the nuclear rest risk. The RSK confirmed, that the implementation of the passive autocatalytic recombiners is a safety measure for the controlled removal of the hydrogen in beyond design accident conditions. Assumption : Failure of the whole residual heat removal system (RHRS) and non sufficient effect of the systems which have been installed for beyond design accident conditions. Effect on the reactor coolant system (RCS): The reactor core will be damaged by non sufficient cooling with the output of hydrogen because all the specified emergency actions have failed. The overheating of the core is responsible for the production of hydrogen by the reaction of zirconium of the fuel-rod cladding with the water vapour. In case of nuclear superheating it would be possible that the reactor vessel would start smelting. The interacting between the core and the concrete, together with the armouring of the biological shield would also produce hydrogen. The hydrogen would escape together with the water vapour out of the leak and would spread out into the whole containment. Results : the number and the position of the different sized recombiners were determined on engineering judgement. the following 4 scenarios are representatively. The 4 scenarios were analyzed for in beyond design accident conditions with the MELCOR-Code: No. 1: Loss of main feedwater supply with primary feed and bleed. No. 2

  15. Health and environmental impact of depleted uranium

    International Nuclear Information System (INIS)

    Depleted Uranium (DU) is 'nuclear waste' produced from the enrichment process and is mostly made up of 238U and is depleted in the fissionable isotope 235U compared to natural uranium (NU). Depleted uranium has about 60% of the radioactivity of natural uranium. Depleted uranium and natural uranium are identical in terms of the chemical toxicity. Uranium's high density gives depleted uranium shells increased range and penetrative power. This density, combined with uranium's pyrophoric nature, results in a high-energy kinetic weapon that can punch and burn through armour plating. Striking a hard target, depleted uranium munitions create extremely high temperatures. The uranium immediately burns and vaporizes into an aerosol, which is easily diffused in the environment. People can inhale the micro-particles of uranium oxide in an aerosol and absorb them mainly from lung. Depleted uranium has both aspects of radiological toxicity and chemical toxicity. The possible synergistic effect of both kinds of toxicities is also pointed out. Animal and cellular studies have been reported the carcinogenic, neurotoxic, immuno-toxic and some other effects of depleted uranium including the damage on reproductive system and foetus. In addition, the health effects of micro/ nano-particles, similar in size of depleted uranium aerosols produced by uranium weapons, have been reported. Aerosolized DU dust can easily spread over the battlefield spreading over civilian areas, sometimes even crossing international borders. Therefore, not only the military personnel but also the civilians can be exposed. The contamination continues after the cessation of hostilities. Taking these aspects into account, DU weapon is illegal under international humanitarian laws and is considered as one of the inhumane weapons of 'indiscriminate destruction'. The international society is now discussing the prohibition of DU weapons based on 'precautionary principle'. The 1991 Gulf War is reportedly the first

  16. The dynamics of coherent flow structures within a submerged permeable bed

    Science.gov (United States)

    Blois, G.; Best, J.; Sambrook Smith, G.; Hardy, R. J.; Lead, J.

    2009-12-01

    The existence of complex 3D coherent vortical structures in turbulent boundary layers has been widely reported from experimental observations (Adrian et al., 2007, Christensen and Adrian, 2001) and investigations of natural open channel flows (e.g. Kostaschuk and Church, 1993; Best, 2005). The interaction between these flow structures and the solid boundary that is responsible for their generation is also receiving increasing attention due to the central role played by turbulence in governing erosion-deposition processes. Yet, for the majority of studies, the bed roughness has been represented using rough impermeable surfaces. While not inherently acknowledged, most research in this area is thus only strictly applicable to those natural river beds composed either of bedrock or clay, or that have armoured, impermeable, surfaces. Recently, many researchers have noted the need to account for the role of bed permeability in order to accurately reproduce the true nature of flow over permeable gravel-bed rivers. For these cases, the near-bed flow is inherently and mutually linked to the interstitial-flow occurring in the porous solid matrix. This interaction is established through turbulence mechanisms occurring across the interface that may be important for influencing the incipient motion of cohesionless sediment. However, the nature of this turbulence and the formation of coherent structures within such permeable beds remain substantially unresolved due to the technical challenges of collecting direct data in this region. In this paper, we detail the existence and dynamic nature of coherent vortical structures within the individual pore spaces of a permeable bed submerged by a free stream flow. Laboratory experiments are reported in which a permeable flume bed was constructed using spheres packed in an offset cubic arrangement. We applied a high resolution E-PIV (Endoscopic Particle Image Velocimetry) approach in order to fully resolve the instantaneous structure of

  17. Tratamento das formas severas de miastenia pelo ACTH por via intravenosa

    Directory of Open Access Journals (Sweden)

    José Lamartine de Assis

    1960-12-01

    Full Text Available O autor inicia o trabalho referindo as bases bioquímicas, fisiopatológicas e anátomo-patológicas do tratamento da miastenia pelo ACTH. Na miastenia grave há diminuição da síntese da acetilcolina no organismo, atuando o ACTH no sentido de aumentar esta síntese seja diretamente, por ativação da colinacetilase, seja indiretamente, mediante a redução da massa dos tecidos linfóides, em particular do timo, responsáveis pela elaboração de substâncias que diminuem a síntese da acetilcolina. O autor empregou o ACTH "Armour" e a Cortrofina "Organon", nas doses de 2,5 a 25 mg, sempre pela via intravenosa, diluídos em 250 a 1.000 ml de soluto glicosado a 5%, administrado gota a gôta, na velocidade média de 20 gôtas por minuto, durante 8 horas. Como medicação associada foi administrada a Prostigmina a todos os pacientes, substituída, depois, em alguns casos, pelo Mestinon ou pela Mytelaze. Como adjuvantes foram empregados o cloreto de potássio (2 a 8 g por dia e o sulfato de efedrina (25 mg 3 vêzes ao dia. Os pacientes foram mantidos em regime hiperprotéico e acloretado, sendo tomados todos os cuidados inerentes ao uso do ACTH. Foram estudados 10 pacientes portadores de miastenia com sintomatologia acentuada (8 casos e média (2 casos. Todos os doentes vinham sendo tratados com drogas anticolinesterásicas em doses adequadas (Prostigmina, Mestinon, Mytelaze e a sua sintomatologia respondia cada vez menos a esta terapêutica. Em alguns casos haviam sido tentados outros tratamentos (timectomia, denervação do seio carotídeo, irradiação da região tímica sem resultado. É de notar que as remissões espontâneas neste grupo de enfermos foram excepcionais e de curta duração. A evolução foi acompanhada do ponto de vista clínico, com a sintomatologia classificada como muito acentuada, acentuada, média e leve. Em todos os casos houve remissão completa ou quase completa da sintomatologia após dosagens variáveis de ACTH; no

  18. Radiation-resistance assessment of IR fibres for ITER thermography diagnostic system

    International Nuclear Information System (INIS)

    The actively cooled target plates in the divertor of ITER will be subjected to high thermal fluxes (∼ 10 MW/m2). These target plates are compound structures of an armour material at the surface - either carbon fibre reinforced carbon (CFC) or tungsten - and a water cooled CuCrZr structure inside or below. The thermal limit of the interface between the two materials must not exceed 550 oC. Therefore, the temperature must be carefully monitored to prevent structural damages of the divertor plates. Non contact measurements of the temperature offer the advantage to avoid weakening of the cooling plate structure which is already quite complex to manufacture. Infrared thermography of the target surface is therefore considered as a possible solution. Recently a diagnostic concept for spectrally resolved ITER divertor thermography using optical fibres has been proposed by CEA-Cadarache. However, the divertor region will have to face high-radiation flux and the radiation-resistance of InfraRed (IR)-fibres must be evaluated. In collaboration with CEA-Cadarache, an irradiation program has been started at SCK-CEN (Mol, Belgium) with the aim to measure the radiation-induced absorption of different IR fibre candidates operating in the 1-5 μm range. We selected various commercially available IR technologies: ZrF4, Hollow-Waveguide, Sapphire and Chalcogenide. For wavelengths below 2 μm we also tested low-OH silica fibres. We carried out a gamma irradiation at a maximum dose-rate of 0.42 Gy/s up to a total dose of about 5000 Gy. We showed that the optical transmission of ZrF4 fibres strongly decreased under gamma radiation, primarily for wavelengths below 2 μm. In this type of fibre typical optical losses can reach 50 % at 5000 Gy around 3 μm. Nevertheless, the optical transmission can be significantly recovered by performing a thermal annealing treatment at a temperature of 100 oC. We also irradiated a Silver-coated hollow waveguide fibre at the same dose-rate but up to 25 k

  19. Foreword

    Science.gov (United States)

    Cirne, José

    2006-08-01

    increase the contacts between university and college researchers and people from industry in particular themes of joint interest. At the moment there are two sub-groups, the Light-Weight Armour Group (LWAG) and the Group of Transport Security (CRASH), developing their activities and organizing regular workshops. But DYMAT is keen on seeing others. I cannot finish this small text without thanking most sincerely the CEA (Commissariat à l'Énergie Atomique) at Valduc, and their collaborators, for having accepted the task of organising the Conference. A particular and very special thank you to Richard Dormeval, not only for the excellent and arduous work that, as chairman of the Conference, developed during the long period of its preparation, but also for his continuous assistance as Vice-President of the DYMAT Association over the last three years. I would equally like to thank the friendly and engaged team of the Administrative Council of the Association for all their work in reading, selecting and re-reading manuscripts, thus assuring our Conference is of a high academic level. Together with my colleagues at the DYMAT Bureau, I hope that this Conference can contribute on the development of the knowledge in the field of the dynamic behaviour of materials. Especially I hope that the participants can profit from these days exchange their experiences and develop contacts and projects. Please, enjoy these days in Dijon. Coimbra, the 11th of May 2006 José Cirne President of Dymat Association

  20. Movable scour protection. Model test report

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, R.

    2002-07-01

    sand to pass between the individual concrete blocks. Based on the tests with general seabed lowering, the following conclusions were reached: 1. The scour protection material placed in the developed scour hole is the most efficient solution to follow seabed subsidence, 2. A local scour in the scour protection itself of up to D/2 can be allowed without endangering the general functioning of the scour protection, 3. During the subsidence the scour material will undergo an armouring increasing the stability. Conclusions for Tripods were, that the maximum scour depth at a leg without any scour protection was found from a strong steady current. The scour was highly unevenly distributed due to inherent hydrodynamic instabilities. The strong scour was at one of the support piles, not underneath the centre column. Tests were made with a scour protection placed in the natural scour hole. The scour protection maintained the cohesion during subsidence of 3 times the pile sleeves, but with the same instabilities as observed in the scour tests without scour protection. Scour developed rapidly on one pile sleeve and it may be concluded that the scour protection does not fulfil its objective unless it is increased. In this case, however, it will be more economical to size the piles and pile sleeves for subsidence and scour. (BA)

  1. Deuterium inventory in tungsten after plasma exposure. A microstructural survey

    International Nuclear Information System (INIS)

    Tungsten is a promising material for armouring the plasma-facing wall of future nuclear fusion experiments and power plants. It has a very high melting point, good thermal conductivity and is highly resistant against physical sputtering by energetic particles from the plasma. It also has a very low solubility for hydrogen isotopes. This is important both for safety and also for economic reasons, in particular with regard to the radioactive fusion fuel tritium. Due to this low solubility, the retention of hydrogen isotopes in tungsten materials after exposure to a plasma is dominated by the trapping of hydrogen isotopes at tungsten lattice defects. Therefore, a strong dependence of the hydrogen isotope retention on the microstructure of the tungsten is to be expected. This work describes a survey study of tungsten with different microstructures exposed to deuterium plasmas under a wide range of different plasma exposure conditions. The isotope deuterium was used because its natural abundance is much smaller than that of hydrogen (i.e., 1H). This allows detecting even very small amounts retained in the tungsten practically without background signal. Furthermore, the use of deuterium allows utilising the nuclear reaction 2D(3He,p)4He for depth-resolved quantification of the deuterium inventory up to depths of several microns. In order to standardise the specimens as far as possible, they were all cut from the same initial material from a single manufacturing batch. After a chemo-mechanical polishing procedure, which produces a well-defined surface, the specimens were annealed at either of four different temperatures in order to modify the grain structure and the dislocation density. These were then characterised by scanning electron microscopy and scanning transmission electron microscopy. The specimens were subsequently exposed in a fully characterised deuterium plasma source at different specimen temperatures, ion energies and deuterium fluences. In addition to

  2. A method for assessing the physical recovery of Antarctic desert pavements following human-induced disturbances: a case study in the Ross Sea region of Antarctica.

    Science.gov (United States)

    O'Neill, Tanya A; Balks, Megan R; López-Martínez, Jerónimo; McWhirter, Judi L

    2012-12-15

    With increasing visitor numbers an understanding of the impacts of human activities in Antarctic terrestrial environments has become important. The objective of this study was to develop a means for assessing recovery of the ground surface desert pavement following physical disturbance. A set of 11 criteria were identified to assess desert pavement recovery. Assessed criteria were: embeddedness of surface clasts; impressions of removed clasts; degree of clast surface weathering; % overturned clasts; salt on underside of clasts; development of salt coatings; armouring per m(2); colour contrast; evidence of subsidence/melt out; accumulation of salt on cut surfaces; and evidence of patterned ground development. Recovery criteria were assigned a severity/extent rating on a scale from zero to four, zero being highly disturbed, and four being undisturbed. A relative % recovery for each criteria was calculated for each site by comparison with a nearby undisturbed control area, and an overall Mean Recovery Index (MRI) was assigned to each pavement surface. To test the method, 54 sites in the Ross Sea region of Antarctica were investigated including areas disturbed by: bulldozer scraping for road-fill, contouring for infrastructure, geotechnical investigations, and experimental treading trial sites. Disturbances had occurred at timescales ranging from one week to 50 years prior to assessment. The extent of desert pavement recovery at the sites investigated in this study was higher than anticipated. Fifty of the 54 sites investigated were in an intermediate, or higher, stage of desert pavement recovery, 30 sites were in an advanced stage of recovery, and four sites were indistinguishable from adjacent control sites (MRI = 100%). It was found that active surfaces, such as the gravel beach deposits at the Greenpeace World Park Base site at Cape Evans, the aeolian sand deposits at Bull Pass, and the alluvial fan deposits of the Loop Moraine field campsite, recovered relatively

  3. Current Issues in Cosmology

    International Nuclear Information System (INIS)

    about the concordance model and cites a paper of his (astro-ph/0009020) that is entertaining and hard hitting. But is it worth buying 278 pages for the sake of at most 20? I welcomed the opportunity to review this book since I have stuck my neck out even further than Narlikar and Disney, and this journal has even published an article by me in which I question whether the universe is actually expanding (Classical and Quantum Gravity 20 1571). I wanted to see if there were any chinks in the armour of the standard model. I have to say that having read this book, three modern books on cosmology and attended the recent Cosmic Frontiers conference in Durham (UK), I have to agree with Blanchard when he says: 'When I try to find what the weaknesses of the standard big bang are, I get rather more convinced of its robustness!' However, I was glad to see that he does not regard inflation as part of the model, and I do think Disney is right to be sceptical about exaggerated claims for the specific concordance model (rather than the basic big-bang idea). However, what I find immensely impressive is how the one simple idea of the expanding universe has proved so fruitful and successful. (book review)

  4. Current Issues in Cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Barbour, J B [Department of Physics and Astronomy, University of Rochester (United States)

    2007-02-07

    the standard model though he has difficulties with X-ray clusters) and the observer Michael Disney, who expresses radical doubts about the concordance model and cites a paper of his (astro-ph/0009020) that is entertaining and hard hitting. But is it worth buying 278 pages for the sake of at most 20? I welcomed the opportunity to review this book since I have stuck my neck out even further than Narlikar and Disney, and this journal has even published an article by me in which I question whether the universe is actually expanding (Classical and Quantum Gravity 20 1571). I wanted to see if there were any chinks in the armour of the standard model. I have to say that having read this book, three modern books on cosmology and attended the recent Cosmic Frontiers conference in Durham (UK), I have to agree with Blanchard when he says: 'When I try to find what the weaknesses of the standard big bang are, I get rather more convinced of its robustness{exclamation_point}' However, I was glad to see that he does not regard inflation as part of the model, and I do think Disney is right to be sceptical about exaggerated claims for the specific concordance model (rather than the basic big-bang idea). However, what I find immensely impressive is how the one simple idea of the expanding universe has proved so fruitful and successful. (book review)

  5. Phytoplankton of the North Sea and its dynamics: A review

    Science.gov (United States)

    Reid, P. C.; Lancelot, C.; Gieskes, W. W. C.; Hagmeier, E.; Weichart, G.

    Phytoplankton is the major contributor to algal biomass and primary production of the North Sea, although crops of macroalgae can locally be up to 2000 g C.m -2 along the coast of the U.K. and Norway, and microphytobenthos dominates production in the shallow tidal flat areas bordering the coasts of England, the Netherlands, Germany and Denmark. Data collected since 1932 during the Continuous Plankton Recorder Survey show consistent patterns of geographical, seasonal and annual variation in the distribution of phytoplankton and its major taxonomic components. There is a trend of increased colouration in Recorder silks in the southern North Sea until approximately 1975 since when Colour levels (assumed to be indicative of algal biomass) have declined. In the eutrophic Dutch Wadden Sea the algal crop continued to increase; in Dutch coastal North Sea waters a trend of biomass increase reversed since 1984, apparently due to a reduction in Rhine river outflow. Long-term observations made at Helgoland since the 60's also show trends of increasing nutrients and phytoplankton biomass only to 1984. Adverse effects such as deoxygenation, foam formation and toxin production have been linked to mass concentrations of algae known as blooms. There is no evidence from existing reports for an increase in their frequency, although some years stand out with larger numbers. Occurrence of blooms can partly be explained by hydrographic conditions. More than 30 taxa are recognised as occurring in bloom proportions in the North Sea, approximately one third of which can be toxic. The crop of Bacillariophyceae (diatoms) is not likely to increase with eutrophication due to silicate limitation. An extensive subsurface maximum of armoured dinoflagellates, its abundance gouverned by hydrographic conditions, is the most characteristic feature of the central and northern North Sea in the summer months. Abundance, sometimes dominance, of picoplankton and of species that are not readily detected by

  6. Why most agricultural terraces in steep slopes in semiarid SE Spain remain well preserved since their abandonment 50 years go?

    Directory of Open Access Journals (Sweden)

    Cantón, F.

    2010-12-01

    Full Text Available A large part of the agricultural terraces in mountain environments are abandoned, like those from the Filabres range in Almería, SE Spain. While many of such terraces show signs of soil erosion (wall disruptions, surface crusts, pipes and gullies, others in steep slopes remain well preserved after 50 years since their abandonment and still seem to play an active role against soil erosion. In order to know both magnitude of soil erosion and controlling factors in different types of abandoned terraces, a rainfall simulation campaign with a portable sprinkler was carried out in 45 representative microsites. Runoff, derived-infiltration and sediment production were measured and their relationships to basic soil parameters (particle size distribution, pH, EC, organic matter content, aggregate stability, geomorphic position, and ground cover, were examined. Under the average applied rainfall intensity (48 mm/h, which represents a precipitation with a return period of 5 years in the area, narrow bench terraces from steep hillslopes, have larger infiltration values and deliver less sediments than large bank terraces in alluvial plains. The presence of stony pavement sieving crusts on narrow-bench terraces and also on un-terraced alluvial fans, play an essential armouring effect against soil erosion while favouring water infiltration. Considerations are made about the evolution of the different types of traditional terraces in the area under both past agricultural and present abandoned status, and also about possible uses under a sustainable land management policy.

    Una gran parte de las terrazas agrícolas en zonas de montaña están abandonadas, como las de la Sierra de los Filabres en Almería, SE de España. Si bien muchas de dichas terrazas muestran señales de erosión hídrica (destrucción de muros, encostramiento superficial, piping y cárcavas, otras en laderas con pendientes acusadas siguen bien conservadas tras 50 años de abandono y

  7. Book Review:

    Science.gov (United States)

    Barbour, J. B.

    2007-02-01

    about the concordance model and cites a paper of his (astro-ph/0009020) that is entertaining and hard hitting. But is it worth buying 278 pages for the sake of at most 20? I welcomed the opportunity to review this book since I have stuck my neck out even further than Narlikar and Disney, and this journal has even published an article by me in which I question whether the universe is actually expanding (Classical and Quantum Gravity 20 1571). I wanted to see if there were any chinks in the armour of the standard model. I have to say that having read this book, three modern books on cosmology and attended the recent Cosmic Frontiers conference in Durham (UK), I have to agree with Blanchard when he says: 'When I try to find what the weaknesses of the standard big bang are, I get rather more convinced of its robustness!' However, I was glad to see that he does not regard inflation as part of the model, and I do think Disney is right to be sceptical about exaggerated claims for the specific concordance model (rather than the basic big-bang idea). However, what I find immensely impressive is how the one simple idea of the expanding universe has proved so fruitful and successful.

  8. Technical Description Lillgrund Wind Power Plant. Lillgrund Pilot Project

    Energy Technology Data Exchange (ETDEWEB)

    Jeppsson, Joakim; Larsen, Poul Erik; Larsson, Aake (Vattenfall Vindkraft AB, Stockholm (Sweden))

    2008-09-15

    construction period and revealed that (i) the insulation level in the main transformer was too low, (ii) surge arresters needed to be installed in all 48 wind turbines and (iii) some large transients occurring when the 130 kV main circuit breaker was switched on. This caused extra costs and the experience shows that it is vital to perform an electrical systems study in good time before the construction period begins. In general, the working conditions at the Lillgrund site have been good. However, late autumn and winter 2006 the combination of harsh winds and inconsistent current directions made it impossible to perform the offshore work. Situations like these need to be taken into consideration when writing the contract to ensure that the appointment of risk between owner and contractor is clearly defined. Many minor problems and disputes with the contractors can be avoided if the owner has a site representative present on-site during the whole project. This must be required both for production sites for the foundations, concrete or steel, as well as for the offshore work. The foundation contractor and designer underestimated the reinforcement needed to fulfil the requirements from the agreed design code. Experience from earlier projects designed after other codes were not valid. Different kinds of cement can be used for the foundations. If a long lifetime is required the choice of cement can be of importance. A Portland cement with a higher amount of alkali can make cracks self heal, which is beneficial. The characteristic is not present in cement with micro silica, which was the cement chosen for the Lillgrund project. It is recommended that anodes be used as cathode protection system on all foundations, including the transformer station foundation. The influence of the cable armouring should also be taken into consideration in the design. Due to corrosion problems, hand railings are preferably made of aluminium as opposed to painted or galvanised carbon steel. Boat

  9. 装甲兵职业倦怠、疲劳状态对军事绩效的影响

    Institute of Scientific and Technical Information of China (English)

    梁学军; 甘景梨; 段惠峰; 高存友

    2015-01-01

    目的:探讨装甲兵职业倦怠和疲劳状态特点及关系,为提高官兵职业热情,改善军事绩效提供科学依据。方法随机抽取某部138名装甲兵为研究对象,采用工作能力指数量表( WAI )、职业倦怠感量表( MBI )、疲劳评定量表( FAI )和一般情况调查表进行测评,并分析影响WAI的相关因素。结果138名装甲兵中军事绩效良好者51.4%,较差者48.5%;军事绩效良好者职业倦怠量表中情感耗竭感、去个性化和自我成就感因子得分明显低于较差者(P<0.05);军事绩效良好者疲劳评定量表中SS因子、PC因子比较差者低,而RTR/S因子比较差者高(P<0.05或0.01);WAI总分与职务、心理卫生知识了解情况显著正相关,与MBI和FAI呈负相关;多元回归分析显示,心理卫生知识了解情况、SS因子、PC因子和个人成就感4个因素进入回归方程。结论装甲兵的军事绩效受职业倦怠、疲劳状态和心理卫生知识了解情况的影响,加强心理卫生知识教育和素质教育,降低职业倦怠感和疲劳程度,有利于提高官兵的军事绩效。%Objective T o investigate the characteristics and relationships between job burnout and fatigue state a-mong armoured troopers so as to provide scientific basis for improving their occupational passion and military perfor-mance.Methods 138 armored soldiers were randomly selected as the research objects,and work ability index scale (WAI),M aslach BurnoutInventory(M BI),Fatigue AssessmentScale(FAI)and the generalquestionnaire were adopted to measure and evaluate,and the relevant factors influencing WAI were analysized .Results Among the 138 armored soldiers,51.4% had good military performance and 48.5% had poor military performance.The scores of emotional ex-haustion ,deindividuation ,sense of self-accomplishment factors in MBI among armored soldiers with good military per-formance were clearly lower than those among armored soldiers

  10. Analysis of nutritional and odor components in muscle of Siam alligator (Crocodylus siamensis) .%暹罗鳄肌肉营养及腥味成分分析

    Institute of Scientific and Technical Information of China (English)

    阙婷婷; 谢妍; 郑家闻; 胡庆兰; 胡亚芹; 罗自生

    2013-01-01

      利用顶空固相微萃取与气质联用技术对暹罗鳄肌肉脱腥前后的挥发性成分及其变化进行测定,并利用常规肌肉营养测试方法对鳄肉营养成分进行分析.结果表明:在暹罗鳄肌肉中共检测出72种挥发性成分,其中,正己醛为鳄肉腥味的主要成分,与其他成分一起构成鳄肉的特有腥味;在鳄鱼肌肉中水分占76.8%,蛋白质占19.8%,脂肪占2.0%,灰分占1.0%;肌肉中含有16种氨基酸,占肌肉干质量的70.44%,其中必需氨基酸7种,且必需氨基酸的构成比例基本符合联合国粮食与农业组织标准,必需氨基酸指数为60.63%;鳄肉中还富含多种不饱和脂肪酸,二十碳五烯酸( eicosapentaenoic acid , EPA)和二十二碳六烯酸( docosahexaenoic acid , DHA)含量丰富,分别为1.44%和2.96%,且矿物质和微量元素含量丰富,尤其以钙含量最多.表明暹罗鳄肉是一种低脂肪、高蛋白、富含多种不饱和脂肪酸以及矿物质的高品质肉类.%Summary Crocodile is covered in treasure . Its leather has a high reputation in the world , and its armour contains a lot of bone collagen , protein , calcium , phosphorus and so on , and its gallbladder contains more than 20 kinds of bile acids and bilichols , which has a great medicine value . Its blood with antibacterial and antitumor activity is getting the attention of researchers both at home and abroad . There has been growing interest in commercial marketing of the crocodiles meat for human consumption in China , Thailand , America and Australia , which are all artificially breeding Siam alligator , Estuarine crocodile and Nile crocodile etc . Siam alligator is also called Siam freshwater crocodile , Singapore small crocodile , and is commonly known as Thai crocodile . It is getting more and more attention in China . With the increased amount of breeding , the deep processing for the meat of Siam alligator will be the focus of future

  11. Radiology in a Trench Coat. Military Radiology on the Western Front During the Great War

    International Nuclear Information System (INIS)

    For more than a decade and with the centennial of the outbreak of hostilities just around the corner countless historians have revisited the myth of the “Great War of 1914-1918”. The vision upon the conflict has in that way definitely been adjusted. In this perspective we understand how and why the First World War, as a modern and industrial war about to thoroughly influence the 20th century, was the result of a constant evolution. Modern indeed, as the 1789 revolution and in particular the 1813 Leipzig battle heralded conflicts between states and/or nations, rather than opposing kings and their armies as was the case during the Ancien Régime. Industrial also, because of the massive production of weapons, ammunition or uniforms, and because industry managed to produce new weapons such as machine-guns or armoured vehicles. Without forgetting the American Civil War however, it is now largely accepted that the “Great War” is the first example in history of a fully-fledged industrial war. The Great War has recently been perceived as the conflict supplying a defining element to the entire 20th century. “Quite a discovery!”, the reader will be inclined to think. After the era of the “Sun King” or that of “Enlightenment” the 20th century in its turn receives a denominator: it becomes the “century of brutalisation”. Both philosophers and historians in that way wish to stress that, from then onwards, the military aspects fundamentally differed from previous situations: fighting was no longer suspended because of cold weather and the state of war became permanent, with – as a consequence – violence as a total, global and constant reality. A few days of leave somewhere behind the front line could not erase the fact that for the first time in history the soldier, if not wounded or killed, had to face long months or even years of questionable hygiene and miserable food supplies. He had to face an interminable separation from family and loved ones

  12. Obituary: Grote Reber, 1911-2002

    Science.gov (United States)

    Kellermann, Kenneth I.

    2003-12-01

    Grote Reber, a pioneer of radio astronomy died in Tasmania, Australia on 20 December 2002, two days before his 91st birthday. Reber was born in Chicago on 22 December 1911 and grew up in the Chicago suburb of Wheaton, IL. His father, Schuyler Colefax Reber, who was a lawyer and part owner of a canning factory, died when Grote was only 21; his mother, Harriet Grote was an elementary school teacher in Wheaton. Among her 7th and 8th grade students at Longfellow School in Wheaton was young Edwin Hubble with whom Grote later exchanged views on cosmology. Grote graduated from the Armour Institute of Technology (now the Illinois Institute of Technology) with a degree in Electrical Engineering. He excelled in electronics courses but did less well in mathematics. After receiving his degree in 1933, Grote held a series of jobs with various Chicago companies including the Stewart-Warner and Belmont Radio Corporations. Grote had a lifelong interest in electronics. At the age of 16, he received his amateur radio license, W9GFZ, signed by then Secretary of the Interior, Herbert Hoover. After contacting over 50 countries, he was looking for new challenges. He had read about Karl Jansky's discovery of cosmic radio emission and tried to interest astronomers at Yerkes Observatory, but except for Jesse Greenstein, they showed little interest. ``So," as he later related, ``I consulted with myself and decided to build a dish." He took astronomy courses from Philip Keenan and others at the University of Chicago. Using $2,000 of his own funds (about his annual salary), he took the summer of 1937 off from his engineering job at the Stewart-Warner Corporation to erect a 32-ft parabolic transit dish in a vacant lot next to his mother's house. Using his experience and skills as an electrical engineer and radio amateur he designed, built and tested a series of sensitive radio receivers, which he placed at the focal point of his parabolic dish. Following a succession of failures, in the spring

  13. APLICACIÓN DE LA LÓGICA DIFUSA COMPENSATORIA EN LA SELECCIÓN DE OFERTAS DE ARMADURAS ÓPTICAS

    Directory of Open Access Journals (Sweden)

    Rafael A. Espín Andrade

    2010-11-01

    del criterio de expertos y de la Norma ISO 12870: 1998, se obtuvo un modelo basado en Lógica Difusa Compensatoria (LDC, que permite evaluar la calidad de las armaduras ópticas e incluso establecer un orden de importancia a partir de cuán cierto es que la armadura X tiene buena calidad.

     

    For making the right decisions when it comes to buying, it is necessary to assess the suppliers, but the organization has not stated a method to do so, causing high levels of rejected products for quality specifications non-fulfilment. The main goal is to build a model to assess the quality of optic armours. From the experts criterion and the Norma ISO 12870: 1998, a CFL-based model was obtained which allows assessing the quality of armours and even to establish an order concerning the quality.