WorldWideScience

Sample records for armour

  1. Innovative transparent armour concepts

    NARCIS (Netherlands)

    Carton, E.P.; Broos, J.P.F.

    2011-01-01

    Ever since WWII transparent armour consists of a multi-layer of glass panels bonded by thin polymer bond-films using an autoclave process. TNO has worked on the development of innovative transparent armour concepts that are lighter and a have better multi-hit capacity. Two new transparent armour con

  2. Stab resistant body armour

    OpenAIRE

    Horsfall, Ian

    2000-01-01

    There is now a widely accepted need for stab resistant body armour for the police in the UK. However, very little research has been done on knife resistant systems and the penetration mechanics of sharp projectiles are poorly understood. This thesis explores the general background to knife attack and defence with a particular emphasis on the penetration mechanics of edged weapons. The energy and velocity that can be achieved in stabbing actions has been determined for a numb...

  3. 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....

  4. 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。

  5. 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...

  6. 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...

  7. 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 ...

  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...

  9. 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...

  10. 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...

  11. 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...... University, Denmark. The model tests showed that Cubipod armour is more stable than cube armour when exposed to longer waves (steepness approx. 0.025) and has equal stability to cubes in shorter waves. The Cubipod armour layer contained due to its high porosity approximately 6-17% less concrete than the cube...

  12. Stability of Roundheads Armoured with Cubes

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Haagensen, Per; Macineira, Enrique

    2003-01-01

      The paper presents the results of a hydraulic model test study of the influence of concrete mass density and placement method on the stability of cube armour in a 1:2 slope cone shaped roundhead exposed to short ? crested seas. Location and development of armour displacements were studied...... for concrete cubes with mass density of 2.4 t/m 3 and 2.8 t/m 3 in random and regular placement. Significant increase in stability for the higher mass density cubes was found showing that the same dimension cubes can be used in roundhead and trunk, if for the top layer of the most exposed part of the roundhead...

  13. Effect of Clamping Rigidity of the Armour on Ballistic Performance

    Directory of Open Access Journals (Sweden)

    S. N. Dikshit

    1992-04-01

    Full Text Available Influence of the manner in which the armour plates are held during their ballistic testing on the armour performance, has been evaluated. One armour plate was clamped rigidly to the test stand while a second plate of identical composition, hardness, and dimensions was hung loosely from the target holder. Both these plates were impacted with the same type of projectiles and over the same impact velocity range. The nature of ballistic damage evaluated indicates that the manner in which the armour is held during ballistic testing has a negligible influence on its performance at least when the mass of the plate is substantially higher than that of the projectile.

  14. Computer Simulation of an Armoured Battalion Swarming

    OpenAIRE

    Radomir Jankovic

    2011-01-01

    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....

  15. 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...

  16. 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...

  17. 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

  18. 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 layer is similar but the dolosse layer is more permeable and fails as a whole. There was no viscous scale effect. These results and earlier tests in oscillating flow suggest a 'reservoir' effect is important in the stability in steep waves....

  19. Behind armour blunt trauma--an emerging problem.

    Science.gov (United States)

    Cannon, L

    2001-02-01

    Behind Armour Blunt Trauma (BABT) is the non-penetrating injury resulting from the rapid deformation of armours covering the body. The deformation of the surface of an armour in contact with the body wall arises from the impact of a bullet or other projectile on its front face. The deformation is part of the retardation and energy absorbing process that captures the projectile. In extreme circumstances, the BABT may result in death, even though the projectile has not perforated the armour. An escalation of the available energy of bullets and the desire of armour designers to minimise the weight and bulk of personal armour systems will increase the risk of BABT in military and security forces personnel. In order to develop materials that can be interposed between the armour and the body wall to attenuate the transfer of energy into the body, it is essential that the mechanism of BABT is known. There is a great deal of activity within UK and NATO to unravel the interactions; the mechanism is likely to be a combination of stress (pressure) waves generated by the rapid initial motion of the rear of the armour, and shear deformation to viscera produced by gross deflection of the body wall. Physical and computer model systems are under development to characterise the biophysical processes and provide performance targets for materials to be placed between armours and the body wall in order to attenuate the injuries (trauma attenuating backings-TABs). The patho-physiological consequences of BABT are being clarified by research, but the injuries will have some of the features of blunt chest trauma observed in road traffic accidents and other forms of civilian blunt impact injury. The injuries also have characteristics of primary blast injury. An overview diagnosis and treatment is described. PMID:11307682

  20. Nanostructured Bainite-Austenite Steel for Armours Construction

    Directory of Open Access Journals (Sweden)

    Burian W.

    2014-10-01

    Full Text Available Nanostructured bainite-austenite steels are applied in the armours construction due to their excellent combination of strength and ductility which enables to lower the armour weight and to improve the protection efficiency. Mechanical properties of the bainite-austenite steels can be controlled in the wide range by chemical composition and heat treatment. In the paper the results of investigation comprising measuring of quasi - static mechanical properties, dynamic yield stress and firing tests of bainite-austenite steel NANOS-BA® are presented. Reported results show that the investigated bainite-austenite steel can be used for constructing add-on armour and that the armour fulfils requirements of protection level 2 of STANAG 4569. Obtained reduction in weight of the tested NANOS-BA® plates in comparison with the present solutions is about 30%.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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

  6. Hydraulic Stability of Single-Layer Dolos and Accropode Armour Layers

    DEFF Research Database (Denmark)

    Christensen, M.; Burcharth, H. F.

    1995-01-01

    A new design for Dolos breakwater armour layers is presented: Dolos armour units are placed in a selected geometric pattern in a single layer. A series of model tests have been performed in order to determine the stability of such single-layer Dolos armour layers. The test results are presented a...

  7. 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

  8. 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...

  9. A technical note on the armour and equipment for jousting

    Directory of Open Access Journals (Sweden)

    Williams, Alan

    2012-12-01

    Full Text Available This paper discusses the metallurgy of some jousting armours, and other aspects of their equipment. Armours for the joust with sharp lances (scharfrennen were found to be sometimes thinner than armour for the joust of peace (gestech but these examples were made of better metal. Appendices discuss the textile padding, which was an integral part of the protection offered by jousting armour, and some of the lances employed in the joust.

    Este artículo analiza la metalurgia de algunos arneses de justa, y otros aspectos del equipo empleado. Las armaduras para la justa con lanzas afiladas (scharfrennen han resultado ser en ocasiones más delgadas que las empleados para la ‘justa de paz’ (gestech, pero en este caso estaban realizadas con un metal mejor. Los apéndices analizan los acolchados textiles que eran parte integral de la protección que proporcionaba la armadura de justa, y también algunas de las lanzas empleadas.

  10. Stability of Cubipod Armoured Roundheads in Short Crested Waves

    DEFF Research Database (Denmark)

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

    The roundhead is generally the most exposed part of the breakwater. Moreover, in case of rubble mound structures the needed armour size is larger than in the adjacent trunk. Typically units of almost double mass are needed in the roundhead if high density stones or concrete are not used in the head....

  11. Linguistic terms describing different types of armour in Persian manuscripts

    Directory of Open Access Journals (Sweden)

    Moshtagh Khorasani, Manouchehr

    2011-12-01

    Full Text Available The present article investigates different terms describing armour and its diverse typology in Persian martial tradition taken from a selected number of 47 dated Persian manuscripts from the 10th to the 19th centuries C.E. Both human and animal armour used in battlefields are described.

    El presente artículo describe, a partir de 47 manuscritos persas datados entre el siglo X y el siglo XIX d.C., los diversos términos que han designado las armaduras y sus diversas tipologías en la tradición marcial persa, tanto en lo que se refiere a armaduras para hombres como aquellas elaboradas para los animales de batalla.

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

    DEFF Research Database (Denmark)

    Hald, Tue; Burcharth, H. F.

    2000-01-01

    be 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......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....... 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...

  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. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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

    Many of the recent dramatic failures of a number of large rubble mound breakwaters armoured with Dolosse and Tetrapods were caused by breakage of the concrete armour units. Breakage took place before the hydraulic stability of intact units in the armour layers expired. Thus there was not a balance...

  19. 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

  20. 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;

    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...

  1. 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.

  2. 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......This paper presents the results from an experimental investigation of the pressure-induced forces in the core material below the main armour layer and shear stresses on the armour layer for a porous breakwater structure. Two parallel experiments were performed which both involved pore pressure...... pressure gradients were found which exerted a lift force up to ≈60% of the submerged weight of the core material. These maximum outward directed pressure gradients were linked to the maximum run-down event and were in general situated at, or slightly below, the maximum run-down level. Detailed velocity...

  3. 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 la...... of layer is similar but the dolosse layer is more permeable and fails as a whole. There was no viscous scale effect. These results and earlier tests in oscillating flow suggest a 'reservoir' effect is important in the stability in steep waves....

  4. 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.

  5. 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.

  6. 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.

  7. 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...

  8. 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.

  9. 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 structu......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...... and 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....

  10. 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 this is the development of a method for full scale impact testing of prototype units. The method which produces repeatable results is applicable also for quality assessment of the concrete, and is widely used today. The theoretical background for the work is the separation of the loads and related stresses into three...... classes: static, pulsating and impact. In principle each type is described independently, and separately scaled by appropriate scaling laws to prototype sizes. The complex stress field is characterized by the maximum principal tensile stress acting in defined critical sections. This one...

  11. 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.

  12. Characterization of impact behaviour of armour plate materials

    Directory of Open Access Journals (Sweden)

    Nazimuddin G.

    2012-08-01

    Full Text Available Three armour plate materials, including two steels, namely HHA and Mars 300, and an aluminium alloy 5083, were studied under impact loading to determine their behaviour and the mechanisms of deformation that lead to failure. The experimental testing was carried out using either a direct impact compression Split Hopkinson Bar or a torsion Hopkinson Bar. The impact properties and stress-strain cures were obtained as a function of the impact momentum in compression and the angle of twist in torsion. It was found that at the high strain rates developed in the specimen during the tests, the deformation occurs by the formation of adiabatic shear bands (ASBs which may lead to the formation of cracks within the bands and the ultimate failure of the specimens. It was also found that below a certain impact momentum, the deformation is more uniform and no ASBs are formed. Also, ASBs are more likely to form in the BCC metals such as the two steels while diffuse ASBs associated with plastic flow are exhibited in the 5083 aluminum alloy. Microstructural techniques ranging from optical microscopy to atomic force microscopy (AFM were used to study the topography of the ASBs. Also, modelling of the formation was performed. The results provide a comprehensive understanding of the role of ASBs in the failure of these materials.

  13. Influence of Polish Arms, Armour and Militaria on Western Europe

    Directory of Open Access Journals (Sweden)

    Lenkiewicz, Z. S.

    1980-12-01

    Full Text Available Up to approximately the 15th century the arms and the armament of a Polish knight were very similar in style to those used in the west: heavy Armour, heavy sword, and heavy horse. However, in the face of the continuous attacks by Tartars, and later on Turks, on Polish territories, the enemy consisting of very light cavalry, on small but very quick and manageable horses, the heavy knights were of little use. Long before the 15th century the armament and the tactics had to be slowly modified and adapted to the enemy's armament and stratagems.

    Hasta antes del siglo XV, las armas y armamento de los caballeros polacos eran muy similares en estilo a los utilizados en Occidente: una pesada armadura, una pesada espada, un pesado caballo. Sin embargo, frente a los contínuos ataques al territorio polaco, primero de los tártaros y posteriormente de los turcos, utilizando una caballería muy ligera montando caballos de pequeño tamaño pero muy rápidos y manejables, los caballeros tan pesadamente armados eran de poca utilidad. Tácticas y armamento hubieron de adaptarse a las del enemigo. [traducido por la redacción

  14. 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...

  15. 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.

  16. Two-material optimization of plate armour for blast mitigation using hybrid cellular automata

    Science.gov (United States)

    Goetz, J.; Tan, H.; Renaud, J.; Tovar, A.

    2012-08-01

    With the increased use of improvised explosive devices in regions at war, the threat to military and civilian life has risen. Cabin penetration and gross acceleration are the primary threats in an explosive event. Cabin penetration crushes occupants, damaging the lower body. Acceleration causes death at high magnitudes. This investigation develops a process of designing armour that simultaneously mitigates cabin penetration and acceleration. The hybrid cellular automaton (HCA) method of topology optimization has proven efficient and robust in problems involving large, plastic deformations such as crash impact. Here HCA is extended to the design of armour under blast loading. The ability to distribute two metallic phases, as opposed to one material and void, is also added. The blast wave energy transforms on impact into internal energy (IE) inside the solid medium. Maximum attenuation occurs with maximized IE. The resulting structures show HCA's potential for designing blast mitigating armour structures.

  17. Influence of Material Properties on the Ballistic Performance of Ceramics for Personal Body Armour

    Directory of Open Access Journals (Sweden)

    Christian Kaufmann

    2003-01-01

    Full Text Available In support of improved personal armour development, depth of penetration tests have been conducted on four different ceramic materials including alumina, modified alumina, silicon carbide and boron carbide. These experiments consisted of impacting ceramic tiles bonded to aluminum cylinders with 0.50 caliber armour piercing projectiles. The results are presented in terms of ballistic efficiency, and the validity of using ballistic efficiency as a measure of ceramic performance was examined. In addition, the correlation between ballistic performance and ceramic material properties, such as elastic modulus, hardness, spall strength and Hugoniot Elastic Limit, has been considered.

  18. 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.

  19. 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...

  20. 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 w...

  1. 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.)

  2. 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

  3. 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...

  4. 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

  5. Feasibility of using damage to body armour as evidence to prove the degree of intent of wounding

    OpenAIRE

    Watson, Celia H.; Parker, Fiona; Horsfall, Ian; Fenne, Paul

    2008-01-01

    It has become standard practice for Police Authorities to issue stab resistant body armour to all officers who are placed at risk of knife assault. Subsequently if the officer is subjected to a knife attack it has been difficult to prove the degree of intent of wounding by a suspect. Arguments that no real harm could be intended, as the officer was protected by armour, are presented in court to mitigate any sentence of intent to wound. Several Police Forces have requested that damaged armour ...

  6. 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.

  7. Application of Artificial Intelligent For Armour Vehicle Detection Using Digital Image Processing For Aerial Application

    Directory of Open Access Journals (Sweden)

    Kamaruddin Abd Ghani

    2011-01-01

    Full Text Available This paper will presents a new automatic target recognition (ATR algorithm to detect targets such as battle tanks and armoured personal carriers especially that been used by Malaysia Armed Forces from air-to- ground scenario. Numerous friendly-fire incidents justify the need for identification of armour vehicle in both command control and weapon systems. Rapid and reliable identification of the targets at maximum surveillance is a challenging problem. In this paper work, the reliable method to segregate the potential target from the background scene such as Fourier Transform is applied before the extracted target will be process in order to get the detail of edges and boundaries using Hough Transform. The edges will provide sufficient information for the system to generate training data for Artificial Neural Network simulation to recognize the potential target image.

  8. 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...

  9. Numerical Simulation on Ceramic/Metal Armours Impacted by Deformable Projectile

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiaoqing; Yao Xiaohu; Yang Guitong

    2004-01-01

    Numerical simulation for the dynamic response of ceramic/metal armours impacted by deformable projectile is carried out with LS-DYNA3D.The simulated penetration processes are shown. The mushrooming of the projectile is displayed. A distinct conoid shaped zone of fragmented ceramic is observed. A significant bending of the backing plate is revealed. Simulation results match fairly well with the experimental values and the theoretical analysis results. The accuracy of the numerical simulation is validated.

  10. 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

    Recent breakwater failures revealed the shortcomings of the traditional design procedures for concrete armour units. This paper deals with one of them, which can be expressed as the "lack of balance between the hydraulic stability of the armour layer and the mechanical strength or integrity...

  11. 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

    1994-01-01

    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 inbalance between the strength (structural integrity) of ...... 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.......) of 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 loads...

  12. Wounding patterns and human performance in knife attacks: optimising the protection provided by knife-resistant body armour

    OpenAIRE

    Bleetman, A; Watson, Celia H.; Horsfall, Ian; Champion, Steve M.

    2016-01-01

    Stab attacks generate high loads,1 and to defeat them, armour needs to be of a certain thickness and stiffness.2,3 Slash attacks produce much lower loads and armour designed to defeat them can be far lighter and more flexible.Methods and subjects: Phase 1: Human performance in slash attacks: 87 randomly selected students at the Royal Military College of Science were asked to make one slash attack with an instrumented blade on a vertically mounted target. No instructions on how to slash the...

  13. 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.

  14. 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)

  15. 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.

  16. 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.

  17. 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.

  18. 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

    ) of 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 loads on...

  19. 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.

  20. 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.

  1. The Allison V. Armour / William Henry Holmes 1895 Expedition to Mexico

    Directory of Open Access Journals (Sweden)

    Warren Haskin

    2001-11-01

    Full Text Available The foundation of the Field Museum's reputation as a place where serious science is practiced was laid by Allison V. Armour and William Henry Holmes in 1895, a little more than a year after the Museum was established. Looking back after a career of almost 60 years as an anthropologist, and having twice been honored as the outstanding practitioner in the field, Holmes described the trip to Mexico (the only expedition he led during his brief tenure as the Museum's first Curator of An­thropology as "one of the most gratifying and important events of my life." It was also one of the most important events in the history of anthropology at the Museum.

  2. The nutrient supplying capabilities of Uzinura, an endosymbiont of armoured scale insects.

    Science.gov (United States)

    Sabree, Zakee L; Huang, Charlie Y; Okusu, Akiko; Moran, Nancy A; Normark, Benjamin B

    2013-07-01

    An emerging common physiological feature of plant sap-feeding insects is the presence of bacterial endosymbionts capable of providing essential nutrients to their host. These microbial partners are inviable outside of specialized host tissues, and therefore a cultivation-independent approach, namely high-throughput next-generation genome sequencing, can be used to characterize their gene content and metabolic potential. To this end, we sequenced the first complete genome of the obligate endosymbiont, Candidatus 'Uzinura diaspidicola', of armoured scale insects. At 263 431 bp, Uzinura has an extremely reduced genome that is composed largely of genes encoding enzymes involved in translation and amino acid biosynthesis. The tiny size of the Uzinura genome parallels that observed in some other insect endosymbionts. Despite this extreme genome reduction, the absence of a known obligate partner bacterial symbiont suggests that Uzinura alone can supply sufficient nutrients to its host.

  3. 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

  4. Ballistic Behaviour of Tempered Steel Armour Plates under Plane Strain Condition .

    Directory of Open Access Journals (Sweden)

    S. N. Dikshit

    1998-04-01

    Full Text Available The present investigation deals with the ballistic behaviour of tempered steel armour plates under plane strain condition at normal angle of attack. A conical-shaped steel projectile of 6.1 mmdiameter was impacted on 20 mm thick steel annour plates of 350, 450 and 550 Hv hardness, in the velocity range 200 -700 m/s at zero obliquity. Ballistic performance measured in terms of the depthof penetration indicates that, under plane strain condition, behavio1Do" f 550 Hv steel plate is better than those of the other two plates. However, front spalling causes damageto the entry side of the high hardness plate, thus affecting its multihit capability in a limited manner.

  5. 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

  6. 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.

  7. 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.

  8. 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

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

    Science.gov (United States)

    Ramadhan, A. A.; Abu Talib, A. R.; Mohd Rafie, A. S.; Zahari, R.

    2012-09-01

    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.

  10. Hydraulic engines in armoured conveyors; Motores hidraulicos en los transportadores blindados

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Fernandez, N.; Fernandez Equibar, J.L. [Hullera Vasco-Leones, S.A., Leon (Spain)

    1994-05-01

    The Sociedad Anonima Hullera Vasco-Leonesa (HVL) coal mining company in Spain is exploiting a deposit of large subvertical seams which are characterised by being highly tectonised. A very important part of the work of exploitation is developed in the depths of the mine with the aid of secondary ventilation. In the near future, which will characterise itself with the opening of the `New Mine`, this type of work will come to have a significant relevance in underground mining technology. The limitations of space and the presence of methane necessitate, as for many years, the use of pneumatic moving shields, with the great inconveniences which derive from them: reduced energy efficiency, and elevated production of dust and noise. For this HVL seek to introduce in a conventional working, at the bottom of the mine, a system of armoured conveyors driven by hydraulic units, which besides reducing and/or eliminating the problems referred to above serve, as in the past, to extend hydraulic energy into other parts of mining activity. In order to initiate the proposed investigation a pilot project will be partially financed by Ocicarbon. 5 figs.

  11. Ti-doped isotropic graphite: A promising armour material for plasma-facing components

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Rosales, C. [CEIT and Tecnun (University of Navarra), Paseo de Manuel Lardizabal, 15, E-20018 San Sebastian (Spain)], E-mail: cgrosales@ceit.es; Lopez-Galilea, I.; Ordas, N. [CEIT and Tecnun (University of Navarra), Paseo de Manuel Lardizabal, 15, E-20018 San Sebastian (Spain); Adelhelm, C.; Balden, M. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); Pintsuk, G. [Forschungszentrum Juelich GmbH, EURATOM Association, D-52425 Juelich (Germany); Grattarola, M.; Gualco, C. [Ansaldo Ricerche S.p.A., I-16152 Genoa (Italy)

    2009-04-30

    Finely dispersed Ti-doped isotropic graphites with 4 at.% Ti have been manufactured using synthetic mesophase pitch 'AR' as raw material. These new materials show a thermal conductivity at room temperature of {approx}200 W/mK and flexural strength close to 100 MPa. Measurement of the total erosion yield by deuterium bombardment at ion energies and sample temperatures for which pure carbon shows maximum values, resulted in a reduction of at least a factor of 4, mainly due to dopant enrichment at the surface caused by preferential erosion of carbon. In addition, ITER relevant thermal shock loads were applied with an energetic electron beam at the JUDITH facility. The results demonstrated a significantly improved performance of Ti-doped graphite compared to pure graphite. Finally, Ti-doped graphite was successfully brazed to a CuCrZr block using a Mo interlayer. These results let assume that Ti-doped graphite can be a promising armour material for divertor plasma-facing components.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Modelling and analysis of material removal rate and surface roughness in wire-cut EDM of armour materials

    Directory of Open Access Journals (Sweden)

    Ravindranadh Bobbili

    2015-12-01

    Full Text Available The current work presents a comparative study of wire electrical discharge machining (WEDM of armour materials such as aluminium alloy 7017 and rolled homogeneous armour (RHA steel using buckingham pi theorem to model the input variables and thermo-physical characteristics of WEDM on material removal rate (MRR and surface roughness (Ra of Al 7017 and RHA steel. The parameters of the model such as pulse-on time, flushing pressure, input power, thermal diffusivity and latent heat of vaporization have been determined through design of experiment methodology. Wear rate of brass wire increases with rise in input energy in machining Al 7017. The dependence of thermo-physical properties and machining variables on mechanism of MRR and Ra has been described by performing scanning electron microscope (SEM study. The rise in pulse-on time from 0.85μs to 1.25μs causes improvement in MRR and deterioration of surface finish. The machined surface has revealed that craters are found on the machined surface. The propensity of formation of craters increases during WEDM with a higher current and larger pulse-on time.

  17. 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.

  18. 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.

  19. 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

    This paper introduces Finite Element Method modelling techniques applied to wire armoured submarine three-core cables, whose nominal voltages range from 36 to 245 kV. The analysis is focused on the implementation of the net voltage cancellation principle in a 2D environment. The model is utilized...

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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...

  6. 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...

  7. 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

  8. Numerical simulation of ballistic impact on composite armours%复合装甲抗侵彻性能的数值分析

    Institute of Scientific and Technical Information of China (English)

    过超强; 赵桂平

    2013-01-01

    用数值分析的方法分别对金属、陶瓷、纤维增强复合材料组成的层合板和由陶瓷球填充的金属四边形蜂窝夹芯结构在冲击载荷作用下的抗侵彻性能进行了模拟计算.其中冲击载荷由12.7mm直径的刚性穿甲弹模拟.研究了不同构型靶板在侵彻过程中对动能量的吸收机理,分析了两种复合靶板各组分材料的吸能特性,并比较了不同靶板的弹道极限速度V50.研究结果表明:在相同面密度条件下,层合复合靶板中具有最强抗弹性能的陶瓷层与纤维层的最佳比例是2.22,其与4340钢均质靶板相比质量减轻了33%;蜂窝填充陶瓷结构的靶板中灌注环氧树脂后其弹道极限速度提高了13%.%Finite element analysis using LS-DYNA has been performed to investigate the penetration-resistance properties of composite armours.A 3-D model consisting of the various discrete layers of the armour has been built and subjected to transient dynamic loading.The projectile is a bullet with 12.7mm diameter.The dynamic responses of the integral armour having two different types of core topology: multi-component layers of 4340 steel,B4C ceramic and FRP core and square honeycomb filled with ceramic ball and epoxy core are simulated and analyzed.Numerical modeling is used to obtain an estimate for the ballistic limit velocity (V50) and simulate penetration processes.The focus is placed on the energy absorption capabilities of different component layers with same density per unit area.Results of the study indicate that the composite armour having thickness ratio of 2.22 between ceramic and FRP layers is an excellent one with highest ballistic limit velocity in all laminated composite armours and its mass is 33% lighter than that of 4340 steel target.Furthermore,it is found that the V50 of composite armour with square honeycomb filled with ceramic ball and epoxy cores is 13% higher than that without epoxy filled.

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

    Institute of Scientific and Technical Information of China (English)

    P. SIVARAJ; D. KANAGARAJAN; V. BALASUBRAMANIAN

    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. The scanning electron microscope is used to characterie the fracture surfaces. The solution treatment followed by ageing heat treatment cycle is found to be marginally beneficial in improving the tensile properties of friction stir welds of AA7075-T651 aluminium alloy.

  10. 安德玛公司与MapMyFitness公司的合并%Mergers and Acquisitions of Under Armour and MapMyFitness

    Institute of Scientific and Technical Information of China (English)

    曹娜娜

    2016-01-01

    在激烈的市场竞争环境中,企业唯有不断发展壮大才可以生存下去,企业取得发展可以通过内部投资,也可以通过并购。近几年,企业并购浪潮愈演愈烈,企业并购已经成为市场经济发展的必然产物。文章选取安德玛并购MapMyFitNess这个案例进行研究,第一部分介绍了安德玛公司和MapMyFitNess的基本情况,以及实现合并的相关信息;第二部分分析了安德玛并购MapMyFitNess的原因,主要从进入壁垒和合并协同效应两个方面进行了分析;第三部分阐述了此次合并给安德玛公司在财务方面产生的影响;第四部分结合安德玛目前的发展证实了此次并购是安德玛公司的明智之举。%In the fierce market competition environment, enterprises need constant development to survive. The internal investment and mergers and acquisitions can make enterprises to develop. In recent years, the merger and acquisition of enterprises are fiercer and fiercer, and mergers and acquisitions have become the inevitable product of the development of the market economy. This paper researches the case of mergers and acquisitions of MapMyFitNess by Under Armour. In this paper, the first part introduces the basic situations of Under Armour and MapMyFitNess and the relevant information of the mergers and acquisitions. The second part analyzes the reasons of the merger and acquisition of MapMyFitNess, mainly from two aspects: entry barriers and merger synergies effect. The third part expounds the influence of the mergers and acquisitions on Under Armour in the financial aspect. The fourth part combines with the current development of Andemar to confirm that this acquisition is wise.

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    P. Sivaraj

    2014-03-01

    Full Text Available 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. The scanning electron microscope is used to characterie the fracture surfaces. The solution treatment followed by ageing heat treatment cycle is found to be marginally beneficial in improving the tensile properties of friction stir welds of AA7075-T651 aluminium alloy.

  13. Experimental Investigation on the Performance of Armour Grade Q&T Steel Joints Fabricated by Flux Cored Arc Welding with Low Hydrogen Ferritic Consumables

    Institute of Scientific and Technical Information of China (English)

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

    2009-01-01

    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) and softening 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 to avoid HIC because of higher solubility for hydrogen in austenitic phase. Recent studies revealed that low hydrogen ferritic (LHF) steel consumables can also be used to weld Q&T steels, which can give very low hydrogen levels in the weld deposits and required resistance against cold cracking. Hence, in this investigation an attempt has been made to study the performance of armour grade Q&T steel joints fabricated by flux cored arc welding with LHF steel consumables. Two different consumables namely (i) austenitic stainless steel and (ii) low hydrogen ferritic steel have been used to fabricate the joints by flux cored arc welding (FCAW) process. The joints fabricated by LHF consumable exhibited superior transverse tensile properties due to the presence of ferrite microstructure in weld metal. The joints fabricated by ASS consumable showed higher impact toughness due to the presence of austenitic phase in weld metal microstructure. The HAZ softening in coarse grain heat affected zone (CGHAZ) is less in the joints fabricated using LHF consumable due to the lower heat input involved during fabrication compared to the joints fabricated using ASS consumables.

  14. Research on Process of Gdouble Gas Sheielded TIG Welding Applied on Sheet Armour Steel%双层气流保护TIG焊接在薄装甲钢上的工艺研究

    Institute of Scientific and Technical Information of China (English)

    李桂华; 杨炙坤; 王宇琪

    2013-01-01

    通过进行金相分析和力学性能检测等试验,开展双层气流保护 TIG 焊接在某薄装甲钢上的工艺研究,确定合理有效的焊接工艺。试验结果表明,可以将该焊接工艺中的双层气流保护 TIG 焊接技术应用于某薄装甲钢的焊接上,从而大幅度提高了焊接效率。%Based on the content of metallographic analysis and mechanics performance test,a technical research on doub-le gas shielded TIG welding used on sheet armour steel was carried out,and a reasonable and effective welding process was defined.The testing results showed that adopting a reasonable and effective process,double gas shielded TIG welding can be used on certain sheet armour steel welding,which highly improved the welding efficiency of that.

  15. Salinity tolerance of non-native suckermouth armoured catfish (Loricariidae: Pterygoplichthys) in south-eastern Mexico: implications for invasion and dispersal

    Science.gov (United States)

    Capps, Krista A.; Nico, Leo G.; Mendoza-Carranza, Manuel; Arevalo-Frias, Wendi; Ropicki, Andrew J.; Heilpern, Sebastian A.; Rodiles-Hernandez, Rocio

    2011-01-01

    1. Salinity tolerance is one of several important physiological attributes that determine invasion success and the pattern of dispersal of introduced aquatic organisms. Introduced freshwater fishes able to tolerate elevated salinities have the potential to invade and exploit brackish-water (mixohaline) environments and use estuaries and coastal waters as 'bridges' for dispersing from one coastal river system to another. 2. Several members of the neotropical suckermouth armoured catfish genus Pterygoplichthys (Siluriformes: Loricariidae) have established non-native populations in inland waters of North and Central America, Asia and islands in the Caribbean, and Pacific and Indian oceans. Loricariids are generally considered to be strictly freshwater; but a few naturally occur in mesohaline habitats. 3.Catch and habitat data from 2004–2005 and 2009–2011 fish surveys in the Grijalva–Usumacinta River delta region (south-eastern Mexico) confirmed that introduced Pterygoplichthys populations established in upstream freshwater sites (where these catfish are abundant) have recently dispersed into downstream oligohaline and mesohaline estuarine habitats. During 2009–2011 surveys, these non-native catfish — tentatively identified as P. pardalis or its hybrids — were found in sites with salinities ranging from 1 to 8 ppt (mean 5.2 ppt). 4.Acute-salinity experiments were conducted with Pterygoplichthys (110–302 mm standard length, N=140) captured in the Grijalva–Usumacinta Basin to determine upper salinity tolerance levels. Tests demonstrated that individuals maintained in salinities of 0.2 ppt were able to survive abrupt (acute) exposure to salinities up to 10 ppt with little mortality over 10 days (240 h experimental endpoint). A few individuals survived abrupt exposure to 11 and 12 ppt for 20 or more hours, although none survived more than a few hours at 16 ppt or greater. 5.These field and experimental results provide quantitative evidence that non

  16. 穿越航道的海底管道堆石保护设计方法研究与探讨%Study on Rock Armour Protection Design Method of Subsea Pipeline in Shipping Lanes

    Institute of Scientific and Technical Information of China (English)

    马坤明; 刘志刚; 李庆; 戚晓明; 李旭

    2012-01-01

    The subsea pipeline will be in danger or be damaged under many conditions, especially the severe risk for anchor drop. Rock armour protection method is adopted in this paper. The key technique for rock armour protection design including such contents as dimension of rock berm, trench slope stability, rock grading design and so on are researched, Some suggestions for optimization are presented. The study of this paper has a remarkable means to keep the subsea pipeline safe and economic, and will provide a good theory instruction for engineering design in the future.%穿越航道的海底管道面临着诸多风险,尤其是船舶落锚和拖锚将给其带来严峻的考验.采用的管道保护方法为堆石覆盖保护法.针对堆石保护设计的关键技术,包括堆石层的尺寸设计、管沟边坡稳定性设计、回填石块的粒径级配设计等内容进行了研究和探讨,并就如何进行优化设计提出了一些建议.研究成果在保证管道安全性和经济性方面意义明显,同时还将为今后的工程设计提供一定的理论指导.

  17. HPLC测定五味子丸中五味子醇甲的含量%HPLC determination of the content of fructus schisandrae alcohol armour in fructus schisandrae pill

    Institute of Scientific and Technical Information of China (English)

    李岩; 王彤; 赵俊华

    2015-01-01

    Objective to establish determination method of the content of fructus schisandrae alcohol armour in fructus schisandrae pill.Methods using HPLC spectrum of Agilent using C18 column, mobile phase:methanol:water (65:35).:detection wavelength 250 nm. Column temperature:30℃, velocity:1.0 ml/min .Results fructus schisandrae alcohol armour, within the scope of 0.1076-1.614 mu g, good linear (r=0.9998).[1]the average sample recovery rate was 99.6%, RSD%=0.2%.Conclusion this method is simple and accurate, and reproducible, can be used to control the quality of the fruit of Chinese magnoliavine pill.%目的:建立五味子丸中五味子醇甲的含量测定方法。方法采用高效液相色谱法谱柱Agilent C18,流动相:甲醇:水(65:35);检测波长:250nm。柱温:30℃,流速:1.0ml/min结果五味子醇甲在0.1076—1.614μg范围内,线性良好(r=0.9998)。【1】平均加样回收率为99.6%,RSD%=0.2%。结论本方法简便准确,重复性好,可用来控制五味子丸的质量。

  18. 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.

  19. 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....

  20. Pakistan: opening chinks in the armour.

    Science.gov (United States)

    Chhabra, R

    1998-01-01

    In Pakistan, a dozen young women attended a "Girl Child Project (GCP) Supervisors Meeting" in a rural home. While this gathering hardly seems revolutionary, the young women had to take the unusual step of travelling unescorted to attend, relying on community recognition of their hard-earned status as Baiji (aunt/elder sister). Later, a effervescent leader conducted a tour of her project ward where girls do needlework, operate nursery schools, attend sewing or literacy classes, and tend a vegetable garden. At the start of her 7-year involvement with the GCP, this leader, who now inspires awe for her ability to call a public meeting, was a newly widowed mother of a baby who resented the workshops that forced her to talk to outsiders. Another role model is a leader who used the project to develop skills that landed her a full-time job as an extension worker in the National Rural Support Program. The recent arrangements for this young woman's marriage included the unprecedented agreement of her fiance to live with her widowed mother so his new bride could continue to help care for her three younger siblings. The GCP began in the early 1990s by training 500 young women who, in turn, trained others, has expanded to 10,000 girls in 200 locations, and is beginning another major expansion. While the GCP has achieved community support, it will require connections to governmental programs and nonexploitative market mechanisms in order to continue its success. This effort may be aided by the networking of the Family Planning Association of Pakistan and by the government's new educational policy that focuses on the needs of girls.

  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

    Throughout several years Gabbro rocks have been used for various coast protective constructions and breakwaters at the North Sea Coast and in inner Danish waters. So far the use of Gabbro has been based solely on calculations from Shore Protection Manuals, i.e without model tests. Compared to ord...

  4. 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...

  5. 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 ...

  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. Performance enhancement of armour steel against blunt projectiles using pre-layers

    NARCIS (Netherlands)

    Wal, R. van der; Carton, E.P.; Parent, J.M.

    2013-01-01

    Damage containment is one of the key factors for optimising operational readiness of warships after an internal warhead detonation. Ship designers currently have no other option than to rely on state of the art solutions applied in vehicle and personal protection; mainly ballistic composites. These

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

    DEFF Research Database (Denmark)

    Nielsen, Anders Wedel; Sumer, B. Mutlu; Fredsøe, Jørgen;

    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...

  9. 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...

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

    Science.gov (United States)

    Pekár, Stano; Šobotník, Jan; Lubin, Yael

    2011-07-01

    In a predator-prey system where both intervenients come from the same taxon, one can expect a strong selection on behavioural and morphological traits involved in prey capture. For example, in specialised snake-eating snakes, the predator is unaffetced by the venom of the prey. We predicted that similar adaptations should have evolved in spider-eating (araneophagous) spiders. We investigated potential and actual prey of two Palpimanus spiders ( P. gibbulus, P. orientalis) to support the prediction that these are araneophagous predators. Specific behavioural adaptations were investigated using a high-speed camera during staged encounters with prey, while morphological adaptations were investigated using electron microscopy. Both Palpimanus species captured a wide assortment of spider species from various guilds but also a few insect species. Analysis of the potential prey suggested that Palpimanus is a retreat-invading predator that actively searches for spiders that hide in a retreat. Behavioural capture adaptations include a slow, stealthy approach to the prey followed by a very fast attack. Morphological capture adaptations include scopulae on forelegs used in grabbing prey body parts, stout forelegs to hold the prey firmly, and an extremely thick cuticle all over the body preventing injury from a counter bite of the prey. Palpimanus overwhelmed prey that was more than 200% larger than itself. In trials with another araneophagous spider, Cyrba algerina (Salticidae), Palpimanus captured C. algerina in more than 90% of cases independent of the size ratio between the spiders. Evidence indicates that both Palpimanus species possesses remarkable adaptations that increase its efficiency in capturing spider prey.

  11. 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

  12. 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)

  13. Suction removal of sediment from between armour blocks. Part 2. Waves

    DEFF Research Database (Denmark)

    Dixen, Figen Hatipoglu; Sumer, B. Mutlu; Fredsøe, Jørgen

    2008-01-01

    When a stone/armor layer on a sand bed is exposed to flow, the sand underneath will be agitated by the flow turbulence. When the flow velocity reaches a critical value, the sand will be sucked (winnowed out) from between the armor blocks. In a previous investigation, we studied suction removal...... of sediment in steady currents. The present study is an extension of our previous investigation to waves. The critical condition for the onset of suction is determined. It is found that the onset of suction is governed by three parameters: (1) the sediment mobility number (based on the sediment size); (2......) the ratio of sediment size to stone size, d/D; and (3) the Keulegan-Carpenter (KC) number, based on the armor block/stone size. The variation of the critical mobility number for suction as a function of d/D and KC is determined for the ranges of the parameters 0.001

  14. 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.

  15. 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,

  16. 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...

  17. Ballistic Impact Response of Ceramic-Faced Aramid Laminated Composites Against 7.62 mm Armour Piercing Projectiles

    Directory of Open Access Journals (Sweden)

    Nityananda Nayak

    2013-07-01

    Full Text Available Ballistic impact response of ceramic- composite armor, consisting of zirconia toughened alumina (ZTA ceramic front and aramid laminated composite as backing, against 7.62 mm armor piercing (AP projectiles has been studied. Two types of backing composite laminates i.e. Twaron-epoxy and Twaron-polypropylene (PP of 10 mm and 15 mm thickness were used with a ceramic face of 4mm thick ZTA. The ceramic- faced and the stand alone composite laminates were subjected to ballistic impact of steel core 7.62 mm AP projectiles with varying impact velocities and their V50 ballistic limit (BL was determined. A sharp rise in BL was observed due to addition of ceramic front layer as compared to stand alone ones. The impact energy was absorbed during penetration primarily by fracture of ceramic, deformation and fracture of projectile and elastic-plastic deformation of flexible backing composite layer. The breaking of ceramic tiles were only limited to impact area and did not spread to whole surface and projectile shattering above BL and blunting on impact below BL was observed. The ceramic- faced composites showed higher BL with Twaron-PP as backing than Twaron-epoxy laminate of same thickness. This combination of ceramic-composite laminates exhibited better multi-hit resistance capability; ideal for light weight armor.Defence Science Journal, 2013, 63(4, pp.369-375, DOI:http://dx.doi.org/10.14429/dsj.63.2616

  18. Testiranje balističke otpornosti zaštitnih prsluka / Ballistic resistance of body armour testing

    Directory of Open Access Journals (Sweden)

    Đuro Jovanić

    2006-04-01

    Full Text Available U radu je predstavljena osnova standarda NIJ 0101.04 (Nacionalni Institut Pravde, namenjenog za utvrđivanje minimuma tehničkih zahteva i propisivanje metoda ispitivanja balističke otpornosti zaštitnih prsluka, koji treba da zaštite gornji deo tela od dejstva streljačkog oružja. Standard jeste revizija standarda NIJ 0101.03 iz aprila 1987. i preciznije definiše zahteve u pogledu obeležavanja, kriterijume za prijem i postupke merenja otiska u materijalu iza prsluka. Područje ovog standarda odnosi se samo na balističku otpornost, ali ne i na pretnje od noža i predmeta sa oštrim vrhom. Takođe, ne odnosi se na zaštitne prsluke koji sadrže dopunske elemente ili varijacije u konstrukciji balističkih panela za malu površinu torza, radi povećanja osnovnog nivoa zaštite na ograničenim površinama (bilo balističke ili povrede od tupog vrha. / This work is a basic presentation of NIJ 0101.04 (National Institute of Justice standard, -whose purpose is to establish minimum performance requirements and methods of testing ballistic resistance of body armor intended to protect the torso against gunfire. This standard is a revision of NIJ Standard 0101.03 dated April 1987 and it clarifies the labeling requirements, acceptance criteria, and backface signature measurement procedure. The scope of this standard is limited only to ballistic resistance; and it does not include threats from knives and sharply pointed instruments. In addition, the standard does not include armor that incorporates inserts, or variations in construction of the ballistic panel over small areas of the torso, used for increasing the basic level of protection of the armor (whether ballistic or blunt trauma on localized areas.

  19. 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.

  20. 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.

  1. 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.

  2. 装甲钢抗弹性能数学模型研究%Research on ballistic performance mathematic model of armour steel

    Institute of Scientific and Technical Information of China (English)

    付勇涛; 刘静; 刘武群; 邱长生

    2007-01-01

    借助7.62 mm穿甲燃烧弹测定了硬度40~53HRC、15 mm厚Si-Mn-B装甲钢临界安全角,作为抗弹性能的表征值,测定对应靶板的力学性能,对抗弹性能与力学性能之间的关系进行研究.以临界安全角为因变量,靶板力学性能为自变量,利用人工神经网络和Turbo-Basic编写的多元逐步回归程序建立了Si-Mn-B装甲钢临界安全角与力学性能之间的数学模型,再通过模型预报,选择出最佳抗弹性能与力学性能之间的数学模型模型θ°=15.318 9+8.103 1x(dHB)-0.004 9x(Rm)-0.044 3x(Akv)+0.121 4x(A),并得出了力学性能对抗弹性能的影响程度依次为dHB>Rm>Akv>A.

  3. 天作之合斯蒂芬·库里与安德玛战靴%Stephen Curry & Under Armour Sneakers

    Institute of Scientific and Technical Information of China (English)

    齿轮

    2014-01-01

    作为一个刚刚才生产篮球鞋不久的运动品牌,对安德玛来说,现在已经是非常成功的了。目前为止有五名NBA球员穿着安德玛球鞋在赛场上打球。加上去年秋天和安德玛签约的金州勇士队的顶级射手斯蒂芬·库里,安德玛向篮球鞋界进军的号角正式吹响。

  4. 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

  5. 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.)

  6. 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....

  7. Stability of Reshaping Breakwaters with Special Reference to Stone Durability

    DEFF Research Database (Denmark)

    Frigaard, Peter; Hald, Tue; Burcharth, H. F.;

    1998-01-01

    Traditionally, conventional rubble mound breakwaters are designed with stable armour units, and consequently, very large stones or even artificial armour units are required. reshaping breakwater designs allow reshaping of the seaward slope thus involving stone movements. Ultimately, dependent...

  8. 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

  9. 上海某三甲医院急诊就诊量的现状调查及应对%The present situation of the "Shanghai 3 armour hospital emergency medical consultations investigation and deal with

    Institute of Scientific and Technical Information of China (English)

    金珊; 胡敏

    2014-01-01

    Objective Understanding in different months in a year, patients distribution characteristics in different departments of emergency, and discusses how to take measures according to the volume of emergency department visits changes, which can im-prove the work efficiency.Methods By retrospective survey method, using computer software system, analyzing the data from Jan-uary 1, 2012 to December 31, 2012 in one hospital emergency department visits quantity.Results There are obvious differences in hospital emergency visits.Conclusion According to the variation of emergency department visits, increase emergency consulting room, registration window, the pharmacy window, doctors and nurses numbers when the number of visits in the peak; according to the quantity of work in emergency ,take the measures of medical staff holiday or rest when in the trough.%目的:了解一年中不同月份及不同科室急诊病人的就诊分布特点,探讨如何根据急诊就诊量变化特点采取应对措施,从而提高工作效率。方法采用回顾性调查法,应用计算机软件系统,对某三甲医院2012年1月1日-2012年12月31日急诊就诊量进行数据分析。结果医院急诊就诊量存在明显月份差异。结论根据急诊就诊变化规律,在高峰期增加急诊诊室、挂号窗口、药房窗口、急诊加强医生、护士人数及出诊时间;在低谷时,可适当增加医务人员补休或轮休等措施调节急诊工作量的变化。

  10. Numerical simulation of failure of armour blocks on slope under wave action%波浪作用下斜坡上护面块体断裂破坏的数值模拟

    Institute of Scientific and Technical Information of China (English)

    崔焱; 姜峰

    2015-01-01

    Based on FEM/DEM method, a prototype numerical model was presented to simulate internal stress distribution, crack formation and fracture process of armor blocks on the slopes under wave action. The wave⁃in⁃duced hydrodynamic loads of the structures were calculated using the theoretical solution of the small amplitude wave. The armor blocks movement and contact between the armor blocks and the deformation of the blocks were simulated using the FEM/DEM method. The contact force between blocks was calculated by the penalty function method based on potential function. The combined single and smeared crack model was used to simulate the crack of concrete block. Numerical solution was calculated using the central difference explicit integration algorithm. By the application of numerical model and ANSYS model, the internal stress of concrete blocks under gravity were com⁃pared and analyzed. Two forms of collision failure of blocks were given. The calculation accuracy of stress and defor⁃mation of the numerical model was verified. The relative movement between armor blocks, the stress distribution within the blocks, crack formation and fracture process on the slopes under different wave loads were obtained from numerical calculation. The stress duration curves of different points were put forward. The properties of stress, crack formation and fracture process were discussed.%基于FEM/DEM方法建立原型尺度数值模型,模拟波浪荷载作用下斜坡上护面块体内部的应力分布和断裂破坏过程。其中结构物所受的波浪力采用微幅波的理论解计算,块体之间的运动、接触以及块体变形采用FEM/DEM方法模拟。采用基于势函数的罚函数法计算块体之间的接触力,采用Single/Smeared破坏模型模拟混凝土块体开裂,采用中心差分法的显式积分算法进行数值求解计算。分别采用文中数值模型与ANSYS模型对自重作用下块体的应力进行比较分析,给出了块体碰撞破坏的两种形式,验证了数值模型应力和变形计算的精度。通过数值模拟给出了不同波浪荷载下斜坡上护面块体的运动、内部应力分布、裂缝形成和断裂过程,给出了不同点的应力历时曲线,探讨了块体的应力变化和断裂破坏的特性。

  11. 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.

  12. Investigation on Analytical Model of Ballistic Impact on Light Ceramic/Metal Lightweight Armours%轻型陶瓷/金属复合装甲抗弹分析模型研究

    Institute of Scientific and Technical Information of China (English)

    侯海量; 仲强; 朱锡

    2015-01-01

    To explore the design method of light ceramic composite armor, an approximate analytical model of ballistic impact on ceramic/metal composite armor focused on thin back plate and dishing-shearing-petal failure was proposed, based on response characteristics experimental investigation and analysis of the response characteristics. The model takes into account projectile’s erosion failure and ceramic fragments out of bullet surface, moving in the direction of lateral and the anti-impacting to get the dynamic impacting response and failure in the ceramic/metal composite armor metal back panel and formula of ballistic limit velocity of the ceramic/metal composite armor and calculation. Model analysis results are in good agreement with those obtained with the test results.%为探讨轻型陶瓷复合装甲结构设计,在弹道冲击响应特性试验研究与分析的基础上,针对薄金属背板支撑的陶瓷复合装甲,以金属背板发生碟型变形-剪切-花瓣型失效为分析对象,建立了陶瓷/金属复合装甲侵彻过程的近似解析模型。模型考虑了弹体的侵蚀失效及陶瓷碎片脱离弹头表面,向侧向和反冲击方向的运动,得到了陶瓷/金属复合装甲中金属背板的动态冲击响应及失效,陶瓷/金属复合装甲的弹道极限速度计算公式和弹体的剩余速度计算方法,模型分析结果与试验结果吻合良好。

  13. An Analytical Model of Ballistic Impact on Light Ceramic/Metal Lightweight Armours%轻型陶瓷/金属复合装甲抗弹分析模型研究

    Institute of Scientific and Technical Information of China (English)

    侯海量; 仲强; 朱锡

    2015-01-01

    To explore the design method of light ceramic composite armor, an approximate analytical model of ballistic impact on ceramic/metal composite armor focused on thin back plate and dishing-shearing-petal failure is proposed, based on response characteristics experimental investigation and analysis of the response characteristics. The model takes the projectile’s erosion failure and ceramic fragments out of bullet surface into account, moving in the direction of lateral and the anti-impacting to get the dynamic impacting response and failure in the ceramic/metal composite armor metal back panel and formula of ballistic limit velocity of the ceramic/metal composite armor and calculation. Model analysis results are in good agreement with those obtained with the test results.%为探讨轻型陶瓷复合装甲结构设计,在弹道冲击响应特性试验研究与分析的基础上,针对薄金属背板支撑的陶瓷复合装甲,以金属背板发生碟型变形—剪切—花瓣型失效为分析对象,建立了陶瓷/金属复合装甲侵彻过程的近似解析模型。模型考虑了弹体的侵蚀失效及陶瓷碎片脱离弹头表面,向侧向和反冲击方向的运动,得到了陶瓷/金属复合装甲中金属背板的动态冲击响应及失效,陶瓷/金属复合装甲的弹道极限速度计算公式和弹体的剩余速度计算方法,模型分析结果与试验结果吻合良好。

  14. 海底电力电缆金属护层及铠装返流效果研究及应用%Research and Application on the Reflux Characteristic of Submarine Power Cable's Sheath and Armour

    Institute of Scientific and Technical Information of China (English)

    龚有军; 黎景辉; 许少淦; 赵世雄

    2015-01-01

    通过建立海底电缆芯线、护层及铠装的电流分布方程,分析了正常运行情况下,接地方式、接地电阻、铠装材质对护层、铠装的返流效果的影响.计算结果表明,海底电力电缆的返流性能与其两端的接地状态密切相关.在平行距离较近、长度较长的情况下,海底电力电缆对临近信号电缆的磁感应影响不可忽略.

  15. 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

    which allows studies of armour unit stresses by means of a load-cell technique. The technique necessitates impact load response calibration of the load-cell mounted model armour units against the equivalent response of prototype or large scale armour units. The procedure followed was presented...... and 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 to study...... armour unit stresses in small scale models. This is partly because the strain in model armour units are too small to be recorded, and partly because the scaling law for impact load generated stresses is nonlinear. The paper discusses the scaling laws related to type of stresses and presents a method...

  16. 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...... underground power cable, 1-phase20 km 10(12) kV XLPE armoured underground power cable, 3-phase....

  17. 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)

  18. 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

  19. 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....

  20. Wave Interaction with Porous Coastal Structures

    DEFF Research Database (Denmark)

    Jensen, Bjarne

    of structures are rubble mound breakwaters and berm breakwaters where common structural elements are core material, filter layers and armour layers. The armour stones serves as the main protection of the filter and core material against wave action. Therefore the armour stones must maintain stable when exposed...... are also applied as part of investigating and designing breakwaters. The models can provide more detailed information on some topics, such as pressure attenuation through the porous core material, while it is more difficult to simulate the direct destabilisation and movements of individual stones...... the contribution to generation of turbulence, and destabilizing shear stresses, from the wave breaking, the armour layer, and the porous core was singled out. In Chapter 3 a similar detailed approach was taken towards experimental investigation of the pressure induced forces in the filter layers below the main...

  1. Note on Armor Steel Design: A proposition

    Directory of Open Access Journals (Sweden)

    S. K. Potay

    1982-07-01

    Full Text Available A theoretical approach to the ballistic penetration and armor development has been made and a single phase material with a computer evaluated optimum hardness has been proposed to give a superior performance as an armour.

  2. 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 structu......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....

  3. 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.

  4. 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...

  5. Danida2

    DEFF Research Database (Denmark)

    Henriksen, Mogens

    1996-01-01

    At the request of Danish Ministry of Foreign Affairs, Department TSA.4, suggestions for electrical test procedures to determine possibly damaged of a 1-phase, 30 kV XLPE insulated armoured submarine power cable, has been further evaluated.......At the request of Danish Ministry of Foreign Affairs, Department TSA.4, suggestions for electrical test procedures to determine possibly damaged of a 1-phase, 30 kV XLPE insulated armoured submarine power cable, has been further evaluated....

  6. Thermo-mechanical tests of a CFC divertor mock-up

    Science.gov (United States)

    Cardella, A.; Akiba, M.; Duwe, R.; Di Pietro, E.; Suzuki, S.; Satoh, K.; Reheis, N.

    1994-04-01

    Thermo-mechanical tests have been performed on a divertor mock-up consisting of a metallic tube armoured with five carbon fibre composite tiles. The tube is inserted inside the tiles and brazed with TiCuSil braze (monoblock concept). The tube material is TZM, a molybdenum alloy, and the armour material is SEP CARB N112, a high conductivity carbon-carbon composite. Using special surface preparation consisting of laser drilling, small (˜- 500 μm) holes in the composite have been made to increase the surface wetted by the braze and the resistance. The mock-up has been tested at the JAERI 400 kW electron beam test facility JEBIS. The aim of the test was to assess the performance of the mock-up in screening and thermal fatigue tests with particular attention to the behaviour of the armour to heat sink joint.

  7. INFLUENCE OF SEDIMENT TRANSPORT ON ARMORED SURFACES

    Institute of Scientific and Technical Information of China (English)

    Katinka KOLL; Andreas DITTRICH

    2001-01-01

    Laboratory experiments have been carried out to study the characteristics of sediment transport in steep streams. The question is discussed wether an armoured surfaces is destroyed due to the transport of material, because additional impulses are acting on it, or the layer is sheltered by the transported material, because a part of the stream power is used to move the material. According to the results of the presented experiments, in which the influence of the feeding rate and the feeding duration have been investigated, transported material reaching an armoured river section from upstream always remobilzes bed material, which is immobile under clear water flow conditions. To decide if a static armour layer is either destroyed or not, two simple criteria were chosen: oneconsidering the grain-size distribution of the eroded bed material, and another, which referes to the amount of eroded bed material.

  8. 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

  9. 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

  10. Use of an image converter camera for analysis of ballistic resistance of lightweight armor materials

    Science.gov (United States)

    van Bree, J. L.; van Riet, E. J.

    1991-04-01

    Experiments to measure the ballistic resistance of light weight armour materials normally comprise the determination of the ballistic limit velocity V50 for a standardized fragment simulating projectile. However, in order to characterize these materials in more detail, it is of great interest to know the dynamic response of armour materials at impact. To this end, high speed photography is used to monitor target behaviour during impact and subsequent perforation in a timeresolved manner. Moreover, in the field of personal protection it is of importance to know the maximum temporary indentation for nonpenetrating projectiles at impact velocities near the critical V50 velocity as a parameter for trauma-effect. Experiments, making use of a Imacon camera, are described in which materials for light weight armour applications were screened.

  11. 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.

  12. 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......-up/down and to the stability of dolos armour is shown. A proposal to establish a set of universal graphs for the stability of dolos blocks (or any other “interlocking” blocks) is made....

  13. 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.

  14. 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.

  15. 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...

  16. Stability of Reshaping Breakwaters with Special Reference to Stone Durability

    DEFF Research Database (Denmark)

    Frigaard, Peter; Hald, Tue; Burcharth, H. F.;

    1996-01-01

    inherently cause some breakage and abrasion of the individual stones and thereby also reduced stability. In order to avoid excessive abrasion a high stone quality is demanded or larger stones must be applied when constructed. To allow the designer to account for abrasion and armour stone breakage due...... movements. Also tensile stresses occur, as a result of stone against stone impact are discussed in order to make a more close connection between wave climate, stone movements and abrasion/breakage. Finally, a comparison to selected prototype structures is made to compare the armour stone movement model...

  17. 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.

  18. 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...

  19. 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 ...

  20. Riprap stability on the inner slopes of medium-height breakwaters

    NARCIS (Netherlands)

    Verhagen, H.J.; Van Dijk, B.; Nederpel, A.

    2003-01-01

    Medium height breakwaters are subjected to a considerable amount of overtopping. This implies the armour on the inner slope has to stable against overtopping waves. Existing equations do lack some basic understanding of the process of starting up movement of rock on the inner slopes. In case one re

  1. Bowthrusters and the stability of a riprap revetment

    NARCIS (Netherlands)

    Verhagen, H.J.

    2001-01-01

    Because of problems with the design guidelines produced by PIANC for armoured slopes under attack by bowthrusters, additional work has been done in the Netherlands. On the basis of this work computational rules have been developed. However, because of the increase of bowthruster power, more detailed

  2. Riprap stability on the inner slopes of medium-height breakwaters

    NARCIS (Netherlands)

    Verhagen, H.J.; Van Dijk, B.; Nederpel, A.

    2003-01-01

    Medium height breakwaters are subjected to a considerable amount of overtopping. This implies the armour on the inner slope has to stable against overtopping waves. Existing equations do lack some basic understanding of the process of starting up movement of rock on the inner slopes. In order to get

  3. 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

  4. 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

  5. Thermal shock behaviour of tungsten after high flux H-plasma loading

    NARCIS (Netherlands)

    Wirtz, M.; Linke, J.; Pintsuk, G.; De Temmerman, G.; Wright, G. M.

    2013-01-01

    Previous studies have shown that transient thermal shock loads induce crack networks on tungsten samples especially at low base temperatures. To achieve test conditions which are more relevant for the performance of tungsten-armoured plasma facing components in next step thermonuclear fusion devices

  6. 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.

  7. 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.

  8. On the use of the fictitious wave steepness and related surf-similarity parameters in methods that describe the hydraulic and structural response to waves

    NARCIS (Netherlands)

    Heineke, D.; Verhagen, H.J.

    2007-01-01

    To assess the hydraulic performance of coastal structures - viz. wave run-up, overtopping and reflection - and to evaluate the stability of the armour layers, use is made of the dimensionless surf similarity parameter, as introduced by Battjes (1974). The front side slope of the structure and the wa

  9. 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...

  10. 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

  11. 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...

  12. Design Formulae for Hydraulic Stability and Structural Integrity of Dolos Breakwater Round-Heads

    DEFF Research Database (Denmark)

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

    1995-01-01

    A rational design of Dolos armour unit should incorporate both the hydraulic stability and the structural integrity. The previous tests performed by Aalborg University (AU) resulted in design formulae for the trunk of a 1:1.5 slope Dolos breakwater without superstructure including both...

  13. 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...

  14. Results of a Round Robin ballistic load sensing headform test series

    NARCIS (Netherlands)

    Philippens, M.A.G.; Anctil, B.; Markwardt, K.C.

    2014-01-01

    The majority of methods to assess the behind armour blunt trauma (BABT) risk for ballistic helmets is based on plastic deformable headforms. An alternative, the Ballistic Load Sensing Headform (BLSH) can record the dynamic contact force between helmet back face and the skull. Helmet BABT methods are

  15. 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.

  16. Structural Stability Of Detached Low Crested Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Kramer, Morten; Lamberti, Alberto;

    2006-01-01

    determining armour stone size in shallow water conditions is given together with a rule of thumb for the required stone size in depth-limited design waves. Rock toe stability is discussed on the basis of prototype experience, hard bottom 2-D tests in depth-limited waves and an existing hydraulic stability...

  17. 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...

  18. 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.

  19. 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.

  20. 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.

  1. On The Use Of High-Density Rock In Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Helgason, Einar; Burcharth, H. F.

    2005-01-01

    Natural rock with high density is widely used in the Scandinavian countries. However, the use of natural rock with density higher than 2:9t=m3 is ordinarily associated with some kind of problem solving, e.g. where normal density stones have to be replaced with heavier stones without increasing th...... on stability from the increased density is overestimated by conventional armour stability formulae in case of steep slopes. The infuence of the density depends on the slope angle and the type of armour units....... the construction volume or layer thickness. Most common design formulae do not give a clear conclusion on the in°uence of the rock density on the stability. The present paper presents results of small and large scale model tests in which is used rock with different densities. It is shown that the positive effect...

  2. 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.

  3. 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

  4. Application of Reliability in Breakwater Design

    DEFF Research Database (Denmark)

    Christiani, Erik

    response, but in one area information has been lacking; bearing capacity has not been treated in depth in a probabilistic manner for breakwaters. Reliability analysis of conventional rubble mound breakwaters and conventional vertical breakwaters is exemplified for the purpose of establishing new ways...... by Bologna University. Thereafter a multiple system of failure for the interaction is established. Relevant stochastic parameters are characterized prior to the reliability evaluation. Application of reliability in crown wall design is illustrated by deriving relevant single foundation failure modes...... methods to design certain types of breakwaters. Reliability analyses of the main armour and toe berm interaction is exemplified to show the effect of a multiple set of failure mechanisms. First the limit state equations of the main armour and toe interaction are derived from laboratory tests performed...

  5. 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.

  6. Reshaping Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Frigaard, Peter

    1987-01-01

    The paper deals with the 3-dimensional stability of the type of rubble mound breakwaters where reshaping of the mound due to wave action is foreseen in the design. Such breakwaters are commonly named sacrificial types and berm types. The latter is due to the relatively large volume of armoure...... stones placed in a seaward berm. However, as also conventional armoured breakwaters sometimes do contain a berm it is assumed that a better and more ambiguous designation would be "reshaping" rubble mound breakwaters. The stability of a reshaping type breakwater was tested in a 3-dimensional model...... at The Hydraulics Laboratory, Department of Civil Engineering, University of Aalborg. The object was to study the stability/erosion of the breakwater head and the trunk, the latter exposed to both head-on and oblique irregular waves. To avoid too many parameters a simple breakwater geometry and only one class...

  7. 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.

  8. 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.

  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. 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.)

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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...

  16. 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...

  17. 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 di...... distributions. We emphasize that the instability should be viewed as a crossover phenomenon rather than a clear-cut transition....

  18. 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...

  19. 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...

  20. Crack growth through low-cycle fatigue loading of material ARMOX 500T

    Directory of Open Access Journals (Sweden)

    V. Pepel

    2016-10-01

    Full Text Available This paper presents microstructure analysis of the creation and growth of cracks in uniaxial load. Analyse were done for steel Armox 500T (armour sheet. Results show that cracks are present quit early in steel lifetime. First micro cracks occur before the 200th cycles, whereby crack growth is progressive during further loading. Also it can be seen that after a certain number of cycles there are more longer cracks then shorter ones.

  1. 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....

  2. 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

  3. 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.

  4. Photogrammetric analysis of rubble mound breakwaters scale model tests

    Directory of Open Access Journals (Sweden)

    João Rodrigues

    2016-09-01

    Full Text Available The main goal of this paper is to develop a photogrammetric method in order to obtain arobust tool for damage assessment and quantification of rubble-mound armour layers during physicalscale model tests. With the present work, an innovative approach based on a reduced number ofdigital photos is proposed to support the identification of affected areas. This work considers twosimple digital photographs recording the instants before and after the completion of the physicaltest. Mathematical techniques were considered in the development of the procedures, enabling thetracking of image differences between photos. The procedures were developed using an open-sourceapplication, Scilab, nevertheless they are not platform dependent. The procedures developed enablethe location and identity of eroded areas in the breakwater armour layer, as well as the possibilityof quantifying them. This ability is confirmed through the calculation of correlation coefficients ineach step of the search for the more damaged area. It is also possible to make an assessment of themovement of armour layer units.

  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. 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

  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. 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.

  9. Ancient DNA from the extinct South American giant glyptodont Doedicurus sp. (Xenarthra: Glyptodontidae) reveals that glyptodonts evolved from Eocene armadillos.

    Science.gov (United States)

    Mitchell, Kieren J; Scanferla, Agustin; Soibelzon, Esteban; Bonini, Ricardo; Ochoa, Javier; Cooper, Alan

    2016-07-01

    Glyptodonts were giant (some of them up to ~2400 kg), heavily armoured relatives of living armadillos, which became extinct during the Late Pleistocene/early Holocene alongside much of the South American megafauna. Although glyptodonts were an important component of Cenozoic South American faunas, their early evolution and phylogenetic affinities within the order Cingulata (armoured New World placental mammals) remain controversial. In this study, we used hybridization enrichment and high-throughput sequencing to obtain a partial mitochondrial genome from Doedicurus sp., the largest (1.5 m tall, and 4 m long) and one of the last surviving glyptodonts. Our molecular phylogenetic analyses revealed that glyptodonts fall within the diversity of living armadillos. Reanalysis of morphological data using a molecular 'backbone constraint' revealed several morphological characters that supported a close relationship between glyptodonts and the tiny extant fairy armadillos (Chlamyphorinae). This is surprising as these taxa are among the most derived cingulates: glyptodonts were generally large-bodied and heavily armoured, while the fairy armadillos are tiny (~9-17 cm) and adapted for burrowing. Calibration of our phylogeny with the first appearance of glyptodonts in the Eocene resulted in a more precise timeline for xenarthran evolution. The osteological novelties of glyptodonts and their specialization for grazing appear to have evolved rapidly during the Late Eocene to Early Miocene, coincident with global temperature decreases and a shift from wet closed forest towards drier open woodland and grassland across much of South America. This environmental change may have driven the evolution of glyptodonts, culminating in the bizarre giant forms of the Pleistocene. PMID:27158910

  10. 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.

  11. Las armaduras romanas en Hispania: protectores corporales para la infantería y la caballería

    Directory of Open Access Journals (Sweden)

    Aurrecoechea, Joaquín

    2010-12-01

    Full Text Available The main subject of this paper is the study of roman armours found in Hispania. After a revision of the archaeological evidence, the article suggests a survey in Iberian Peninsula. In that territory, all the recognizable categories of roman armours are attested. Sites from Hispania offers the most advanced late chronology in the whole Empire, regarding with lorica segmentata and embossed breastplate armours.

    El propósito del presente trabajo es el estudio de las armaduras romanas halladas en Hispania. Tras la revisión de las fuentes arqueológicas, se propone una visión de síntesis sobre estas piezas en la península ibérica, donde se documentan todas las variantes de armaduras conocidas. Los yacimientos hispanos han proporcionado la cronología fi nal más avanzada de todo el Imperio, respecto a las armaduras segmentadas y los pectorales repujados. [fr] Ce travail étudie les armures romaines trouvées en Hispania. Après une révision des sources archéologiques disponibles, il propose un bilan de ce type de pièces pour l’ensemble de la péninsule Ibérique, où toutes les catégories d’armures sont attestées. Les sites hispaniques fournissent notamment les attestations les plus anciennes pour la lorica segmentata et pour les pectoraux décorés au repoussé.

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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.

  17. 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 ...

  18. 好龙?恶龙?

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    This year is the year of the dragon according to the traditional Chinese lunar calendar. Dragons are legendary mythical creatures which feature in the myths of many cultures. They are often described as a huge lizard or a snake with lizard-type legs and breathe fire into their enemies. There are two distinct cultural traditions of dragons: the European dragon the Chinese dragon. European dragons are generally depicted as malevolent. They usually live in rivers or having an underground lair or cave. They are commonly described as having hard or armoured hide, and are rarely described as flying, despite often depicted with wings.

  19. 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...... the 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....

  20. 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...

  1. 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.)

  2. The onset of labour: an alternative theory.

    Science.gov (United States)

    Jones, P

    1996-02-01

    This article, based mainly on the theories and discoveries of Wilhelm Reich (1897-1957), puts forward the bio-energetic theory of the onset of labour, which assumes it to be one of many examples of bio-energetic pulsation in the organism. It suggests that chronic muscular tension ('armouring') interferes with this spontaneous pulsation and may account for many of the difficulties experienced by women in labour. A form of psychotherapy ('orgone-therapy') based on these theories may prove helpful in childbirth education, in the non-intrusive induction of labour, and in labour itself. A research project to test this hypothesis is suggested.

  3. 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...... statistics and structure response. The study comprises the influence of interest rate, service lifetime, downtime costs and damage accumulation. Design limit states and safety classes for breakwaters are discussed. The results indicate that optimum safety levels are somewhat higher than the safety levels...

  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 sensitivity of these quantities to the width of the reservoir is discussed. It is demonstrated that front reservoir solutions are more economical than conventional cross section solutions, such as bermed structures and mild slope structures, in cases where low crests and small overtopping discharges...

  5. 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...

  6. 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...

  7. 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.

  8. 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...

  9. 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...

  10. 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.

  11. 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 reflection....... The reflection coefficient is markedly dependent on the wave angle of incidence. The performance of formulae available in the literature is checked against the new dataset and a significant improvement is proposed by including the wave obliquity factor that appears in the traditional expression...

  12. Effect of Fe ion concentration on fatigue life of carbon steel in aqueous CO2 environment

    DEFF Research Database (Denmark)

    Rogowska, Magdalena; Gudme, J.; Rubin, A.;

    2016-01-01

    In this work, the corrosion fatigue behaviour of steel armours used in the flexible pipes, in aqueous solutions initially containing different concentrations of Fe2+, was investigated by four-point bending testing under saturated 1 bar CO2 condition. Corrosion fatigue results were supported with ex...... of Fe2+ marginally above the solubility limit of FeCO3 compared to the samples tested in highly supersaturated solution of Fe2+. Results revealed that the impact of the alternating stresses on the corrosion behaviour of samples reduces with lowering the applied stresses. At the stress range of 100 MPa...

  13. Espinas dérmicas del dinosaurio anquilosaurio Polacanthus en las facies Weald de Salas de los Infantes (Burgos, España

    Directory of Open Access Journals (Sweden)

    Urién, V.

    1999-12-01

    Full Text Available Ankylosaurian dermal armour elements from the Fuente Espudia locality, near Salas de los Infantes (Burgos Province, are described. These remains have been recovered from red clays of the Urbion Group, which belong to the Weald facies of the western Cameros Basin, of possible Barremian-Aptian age (Lower Cretaceous. Based on their general form, two caudal spines are here assigned to the nodosaurid Polacanthus. This represents the first mention of this genus in the Iberian Peninsula. Previous finds in the same area could also be assigned to this armoured dinosaur.Se describen elementos dermatoesqueléticos de un anquilosaurio procedentes del yacimiento de Fuente Espudia, cerca de Salas de los Infantes (Burgos. Los restos fósiles se localizan en arcillas rojas del Grupo Urbión, que forman parte de las facies Weald del sector occidental de la Cuenca de Cameros, de posible edad Barremiense-Aptiense (Cretácico inferior. Dos espinas proceden de la región caudal y, por su forma general, se atribuyen al nodosáurido Polacanthus. Se trata de la primera cita de este género en la Península Ibérica. Hallazgos previos en el mismo área pueden también asignarse a este dinosaurio acorazado.

  14. 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.

  15. 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......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...... and successively repeated with a porous bed. In this paper the focus is on the impermeable bed. Results are obtained experimentally for flow and turbulence between the roughness elements on the sloping bed. Numerical simulations have reproduced the experimental results with good agreements and can hereby add more...

  16. 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.)

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.)

  2. 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

  3. REQUIEM VIR DIE TENK: AD INITIO AD FINEM

    Directory of Open Access Journals (Sweden)

    C.J. Nöthling

    2012-02-01

    Full Text Available Affective statistics are frequently employed to support arguments for and against the continued operational deployment of the tank on the modern battlefield. In statistical evaluations, which of necessity sometimes are based on inferential techniques, military analysts tend to disregard the influence of such variables as technology. Any 'statistical' projections as to the feasibility of tracked armour with main armament should not only take recent conflicts into account but must in fact be founded on a far broader, historically comparative basis of reference. On this premise the operational deployment of the tank is reviewed, with attention given to such determining factors as availability (with production as initial factor, use and losses during WWI, the intermediate years (1919 - 1939, WW II and the post-war period (1945 - 1980. The general conclusion at which the author arrives is that quantative factors playa decisive role in the course and outcome of conflicts in spite of the relative importance of doctrines, battle skill and tactics. However, quantitive considerations and resolutions have also lead to certain misconceptions as to the role of armour in modern warfare. In this respect acolytes of the tank tend to disregard the decisive role of air superiority. At the same time it appears that new developments in the field of manufacture are inadequate to counter the onslaught of fiscal considerations and the growing arsenal of antitank weapons.

  4. DIE GEALLIEERDE BESTETTING VAN MADAGASKAR IN 1942 (DEEL 4 TAMATAVE, TULEAR EN DIE OORGAWE VAN ANNET

    Directory of Open Access Journals (Sweden)

    J.E.D. Grobler

    2012-02-01

    Full Text Available In September 1942,the third stage in Operation Stream-line-Jane, namely the occupation of the port city of Tamatave on the east coast, was executed by British units. This article briefly deals with that operation, in which no Union troops took part, before turning to what was from the South African viewpoint, the more important Operation Rose. In the execution of that operation South Africans for the first and only time during the Second World War were used in an amphibious attack. Tulear, a small port and town, was captured during that operation, and afterwards garrisoned for more than a month, before the South Africans there started moving towards the interior in search of the Vichy French administrator.Meanwhile the troops which occupied Tananarive, supported by a South African armoured car squadron, moved southwards, also in search of the administrator. A few engagements took place, in which the armoured cars played a minor role, before, after about six weeks, the French called for an armistice. Thus ended the campaign in Madagascar, a campaign in which the Vichy French were reluctant to physically defend their colony, although quite prepared to spare no other trouble in prolonging the date of its surrender as long as possible.

  5. Differences in quality characteristics of normal, PSE and DFD pork.

    Science.gov (United States)

    van der Wal, P G; Bolink, A H; Merkus, G S

    1988-01-01

    Differences in water-holding capacity, colour and tenderness/toughness were studied in 21 pork loins belonging to three quality categories, i.e. dark firm dry (DFD), normal and pale soft exudative (PSE). The division into the three groups was based upon the ultimate pH-values of the loins ( 6·4). The PSE loins were characterized by a poor waterholding capacity, higher cooking loss and paler colour in contrast to the DFD category. The normal loins took an intermediate position. Neither sarcomere length, determined on fresh muscle tissue, nor Armour tenderometer values showed significant differences between the various quality categories. This was in contrast to the Warner-Bratzler (W-B) shear force values, determined on cooked loins, which had the lowest values in the DFD category. A strong relationship between the W-B values and the cooking losses was found. It was concluded that neither sarcomere length nor Armour tenderometer measurements were able to predict the shear force values of cooked pork loins.

  6. Handling performance control for hybrid 8-wheel-drive vehicle and simulation verification

    Science.gov (United States)

    Ni, Jun; Hu, Jibin

    2016-08-01

    In order to improve handling performance of a hybrid 8-Wheel-Drive vehicle, the handling performance control strategy was proposed. For armoured vehicle, besides handling stability in high speed, the minimum steer radius in low speed is also a key tactical and technical index. Based on that, the proposed handling performance control strategy includes 'Handling Stability' and 'Radius Minimization' control modes. In 'Handling Stability' control mode, 'Neutralsteer Radio' is defined to adjust the steering characteristics to satisfy different demand in different speed range. In 'Radius Minimization' control mode, the independent motors are controlled to provide an additional yaw moment to decrease the minimum steer radius. In order to verify the strategy, a simulation platform was built including engine and continuously variable transmission systems, generator and battery systems, independent motors and controllers systems, vehicle dynamic and tyre mechanical systems. The simulation results show that the handling performance of the vehicle can be enhanced significantly, and the minimum steer radius can be decreased by 20% which is significant improvement compared to the common level of main battle armoured vehicle around the world.

  7. Integrated development of light armored vehicles based on wargaming simulators

    Science.gov (United States)

    Palmarini, Marc; Rapanotti, John

    2004-08-01

    Vehicles are evolving into vehicle networks through improved sensors, computers and communications. Unless carefully planned, these complex systems can result in excessive crew workload and difficulty in optimizing the use of the vehicle. To overcome these problems, a war-gaming simulator is being developed as a common platform to integrate contributions from three different groups. The simulator, OneSAF, is used to integrate simplified models of technology and natural phenomena from scientists and engineers with tactics and doctrine from the military and analyzed in detail by operations analysts. This approach ensures the modelling of processes known to be important regardless of the level of information available about the system. Vehicle survivability can be improved as well with better sensors, computers and countermeasures to detect and avoid or destroy threats. To improve threat detection and reliability, Defensive Aids Suite (DAS) designs are based on three complementary sensor technologies including: acoustics, visible and infrared optics and radar. Both active armour and softkill countermeasures are considered. In a typical scenario, a search radar, providing continuous hemispherical coverage, detects and classifies the threat and cues a tracking radar. Data from the tracking radar is processed and an explosive grenade is launched to destroy or deflect the threat. The angle of attack and velocity from the search radar can be used by the soft-kill system to carry out an infrared search and track or an illuminated range-gated scan for the threat platform. Upon detection, obscuration, countermanoeuvres and counterfire can be used against the threat. The sensor suite is completed by acoustic detection of muzzle blast and shock waves. Automation and networking at the platoon level contribute to improved vehicle survivability. Sensor data fusion is essential in avoiding catastrophic failure of the DAS. The modular DAS components can be used with Light Armoured

  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. Study on the Technique of Passive Millimeter Wave Detector

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan-mei

    2005-01-01

    In order to initiate the flight immediately when it reaches the top of the pedrail vehicle, technical parameters of radiometer have been designed and speedy effective signal processing method has been adopted. After analyzing the difference of signal characteristic between the main jam and the target, a method of identifying target in time domain is given. The target distinguishing rules are set up by extracting the magnitude, the slope and the width of the signal, combining with distinguishing the dimension of the target. The result of the theoretic analysis shows that the detecting scheme adopted can ensure the detector to identify and orientate the pedrail vehicle's top armour, as well as control the detonation precisely.

  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

    2015-11-03

    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.

  11. Recreational mountain biking injuries.

    Science.gov (United States)

    Aitken, S A; Biant, L C; Court-Brown, Charles M

    2011-04-01

    Mountain biking is increasing in popularity worldwide. The injury patterns associated with elite level and competitive mountain biking are known. This study analysed the incidence, spectrum and risk factors for injuries sustained during recreational mountain biking. The injury rate was 1.54 injuries per 1000 biker exposures. Men were more commonly injured than women, with those aged 30-39 years at highest risk. The commonest types of injury were wounding, skeletal fracture and musculoskeletal soft tissue injury. Joint dislocations occurred more commonly in older mountain bikers. The limbs were more commonly injured than the axial skeleton. The highest hospital admission rates were observed with head, neck and torso injuries. Protective body armour, clip-in pedals and the use of a full-suspension bicycle may confer a protective effect. PMID:20659880

  12. 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.

  13. 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

  14. Experimental and simulation optimization analysis of the Whipple shields against shaped charge

    Institute of Scientific and Technical Information of China (English)

    G.Hussain; A.Hameed; I.Horsfall; P.Barton; A.Q.Malik

    2012-01-01

    Occasionally,the Whipple shields are used for the protection of a space station and a satellite against the meteoroids and orbital debris.In the Whipple shields each layer of the shield depletes part of high speed projectile energy either by brealing the projectile or absorbing its energy.Similarly,this investigation uses the Whipple shields against the shaped charge to protect the light armour such as infantry fighting vehicles with a little modification in their design.The unsteady multiple interactions of shaped charge jet with the Whipple shield package against the steady homogeneous target is scrutinized to optimize the shield thickness.Simulations indicate that the shield thickness of 0.75 mm offers an optimum configuration against the shaped charge.Experiments also support this evidence.

  15. 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

  16. 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.

  17. 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. "

  18. 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.

  19. 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

  20. 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

  1. 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)

  2. 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.

  3. 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.

  4. Operation Savannah: A Measure of SADF Decline, Resourcefulness and Modernisation

    Directory of Open Access Journals (Sweden)

    Rodney Warwick

    2013-02-01

    Full Text Available SADF conventional warfare capacity exhibited a decline during the 1950s, followed by belated efforts at rearmament and consolidation during the 1960s. However, Operation Savannah, the SADF’s intervention in the Angolan civil war during 1975–1976, as the force’s first involvement in a conventional-type war since 1945, exposed SADF weaknesses, but also strengths. Authorised amidst debilitating secrecy by a miscalculating South African government, Savannah demonstrated significant South African military equipment inadequacies, particularly in terms of artillery, armour and the need for an infantry combat vehicle. Savannah also gave hints of SADF strength residing in the resourcefulness of its personnel and their aptitude for mobile warfare. But rapid and effective Cuban military intervention also showed that SADF conventional warfare reaction and capacity needed urgent attention. This article attempts to address some of these themes while following the course of this “first battle” by the SADF after thirty years of relative peace.

  5. 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...... 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......The present state of knowledge when designing coastal structures has improved in the recent years. However the available design methods concerning especially rubble mound structures are characterized by a number of empirical and semi-empirical formulae making model tests inevitable and even when...

  6. 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

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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

    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......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...... relative to mean wave direction, the critical sector is observed in the sector 10°–55° for short waves and in the sector 100°–145° for long waves. A probabilistic approach is developed to predict for one typical roundhead geometry the damage distribution depending on the incomingwaves and structural...

  13. 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.

  14. An annotated checklist of scale insects (Hemiptera: Coccoidea) of Saint Lucia, Lesser Antilles .

    Science.gov (United States)

    Malumphy, Chris

    2014-07-31

    An annotated list of 83 scale insect species (Hemiptera: Sterorrhyncha: Coccoidea) recorded from Saint Lucia is presented, based on data gathered from UK quarantine interceptions, samples collected in an urban coastal habitat in the North West of the Island in 2013, and published records. Thirty-three species (40%) are recorded for the first time for the country, including Dysmicoccus joannesiae (Costa Lima), a South American mealybug, and Poliaspoides formosana (Takahashi), an Asian armoured scale insect pest of bamboo, which are new for the Caribbean region. The economic, environmental and social impacts caused by introduced exotic species of scale insect are discussed. Two predatory midges Diadiplosis ?coccidivora (Felt) and Diadiplosis multifila (Felt) (Diptera: Cecidomyiidae) are recorded for the first time from Saint Lucia. The latter species was observed causing 90% mortality of a large infestation of passion vine mealybug Planococcus minor (Maskell) on soursop fruit. 

  15. 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

  16. 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.

  17. 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

  18. 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

  19. Frequency Dependent Losses in Transmission Cable Conductors

    DEFF Research Database (Denmark)

    Olsen, Rasmus Schmidt; Holbøll, Joachim; Guðmundsdóttir, Unnur Stella

    2011-01-01

    and economical gain, such severe network changes necessitate correct estimation and optimisation of load conditions in the cable grid. Both IEC and IEEE have published standards for rating transmission cables' current carrying capacity. These standards are based on assumptions of a number of parameters......, such as thermal conditions in and around the cable, as well as the heat generated in conductors, screens, armours etc., taking into account proximity and skin effects. The work performed and presented in this paper is concerned with an improved determination of the losses generated in the conductor, by means...... of better calculation of the AC resistance of transmission cable conductors, in particular regarding higher frequencies. In this way, also losses under harmonics can be covered. Furthermore, the model is suitable for modelling of transient attenuation in high voltage cables. The AC resistance is calculated...

  20. 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.

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

    DEFF Research Database (Denmark)

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

    1999-01-01

    that the diameter of the core material in models is chosen in such a way that the Froude scale law holds for a characteristic pore velocity. The characteristic pore velocity is chosen as the average velocity of a most critical area in the core with respect to porous flow. Finally the method is demonstrated......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 fully...... correct scaling. The paper presents an empirical formula for the estimation of the wave induced pressure gradient in the core, based on measurements in models and a prototype. The formula, together with the Forchheimer equation can be used for the estimation of pore velocities in cores. The paper proposes...

  2. Multi response optimization of wire-EDM process parameters of ballistic grade aluminium alloy

    Directory of Open Access Journals (Sweden)

    Ravindranadh Bobbili

    2015-12-01

    Full Text Available In the current investigation, a multi response optimization technique based on Taguchi method coupled with Grey relational analysis is planned for wire-EDM operations on ballistic grade aluminium alloy for armour applications. Experiments have been performed with four machining variables: pulse-on time, pulse-off time, peak current and spark voltage. Experimentation has been planned as per Taguchi technique. Three performance characteristics namely material removal rate (MRR, surface roughness (SR and gap current (GC have been chosen for this study. Results showed that pulse-on time, peak current and spark voltage were significant variables to Grey relational grade. Variation of performance measures with process variables was modelled by using response surface method. The confirmation tests have also been performed to validate the results obtained by Grey relational analysis and found that great improvement with 6% error is achieved.

  3. Strength Analysis Modelling of Flexible Umbilical Members for Marine Structures

    Directory of Open Access Journals (Sweden)

    S. Sævik

    2012-01-01

    Full Text Available This paper presents a 3-dimensional finite element formulation for predicting the behaviour of complex umbilical cross-sections exposed to loading from tension, torque, internal and external pressure including bending. Helically wound armours and tubes are treated as thin and slender beams formulated within the framework of small strains but large displacements, applying the principle of virtual displacements to obtain finite element equations. Interaction between structural elements is handled by 2- and 3-noded contact elements based on a penalty parameter formulation. The model takes into account a number of features, such as material nonlinearity, gap and friction between individual bodies, and contact with external structures and with a full 3-dimensional description. Numerical studies are presented to validate the model against another model as well as test data.

  4. 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

    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......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...... 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....

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. Immune response of rainbow trout (Oncorhynchus mykiss) larvae to Yersinia ruckeri

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Kania, Per Walter; Raida, Martin Kristian;

    Innate immune factors play a crucial role in survival of young fish especially during early stages of life where adaptive immunity is not fully developed. In the present study, we investigated the immune response of rainbow trout larvae (Onchorhynchus mykiss) at an early stage of development. We...... the experimental period. Expression pattern of different cytokines, complement factors, acute phase proteins, antimicrobial peptides, lysozyme, immunoglobulin genes were analysed by using qPCR. It is interesting to note that neither infected nor stimulated larvae showed any significant up/down regulation...... of immune factors at the transcriptional level. It may be speculated that at this stage of life, larvae may combat invading pathogens by using armour consisting of different immune factors without regulating their expression....

  12. 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.

  13. The mediterranean coast of Andalusia (sw spain): the impacts of human coastal structures

    Science.gov (United States)

    Liguori, Vincenzo; Manno, Giorgio; Messina, Enrica; Anfuso, Giorgio; Suffo, Miguel

    2015-04-01

    Spanish coasts, especially the Andalusia Mediterranean one, were affected over time by progressive urbanization and associated construction of defense structures. Such structures protected small coastal sectors but at places triggered processes of coastal erosion and associated degradation of habitats and ecosystems. A correct management of coastal areas must be based on the monitoring of coastal evolution and human pressure. A useful tool to evaluate the level of human anthropization is the estimation of the "Coastal Armouring", e.g. the quantification of coastal defense structures, infrastructures, ports, etc. In this study, available aerial photographs and satellite images from 1956 to 2011 were scanned and geo-referenced and used for the quantitative assessment of coastal human constructions impact on the studied coastal area. The so called coefficient of technogenous impact (K) was used. It results from the relationship between the total length of all maritime structures (groins, moles, seawalls, dikes, channels, etc.) and the entire length of the study coastal section. For this purpose, the Andalusia coast, about 500 km in length, was divided into sections of 1 km. For each one of such sections the technogenous impact was calculated in the 1956 and 2011 documents. The analysis showed that the degree of anthropization in some areas (for example the Port of Montril) has increased considerably, triggering degradation processes in the nearby coastal areas. Results also evidenced as, in many cases, greatest human impacts are linked to the progressive construction of coastal defense. The lack of a general strategy to combat the erosion problem and the urgency in the short term to protect specific parts of the coast led to a reactive approach based initially in the construction of hard structures. Such interventions locally solved erosion problems but gave rise to drowndrift erosion according to the "domino" effect. A more general management plan is needed

  14. Shoreline type and subsurface oil persistence in the Exon Valdez spill zone of Prince William Sound, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Page, D.S. [Bowdoin College, Brunswick, ME (United States). Dept. of Chemistry; Boehm, P.D. [Exponent Inc., Maynard, MA (United States); Neff, J.M. [Neff and Associates, Duxbury, MA (United States)

    2008-07-01

    The grounding of the Exxon Valdez in Prince William Sound (PWS), Alaska in the spring of 1989 resulted in the release of 258,000 barrels of Alaska North Slope crude oil into the marine environment. Nearly 800 km of shoreline were oiled to some degree. There was an unprecedented oil spill cleanup effort following the spill. The shoreline surveys of the spill zone were synthesized in this paper in an effort to demonstrate the relationship between shoreline type and persistence of subsurface oil (SSO) residues. Shoreline surveys of surface and SSO indicate rapid initial oil loss with a decline from about 800 linear km of PWS shoreline in 1989 to about 10 km of oiled shoreline in 1992. The period of rapid loss was attributed to natural physical process, biodegradation and cleanup activities that removed accessible spill remnants from shorelines. This was followed by a slower natural average loss rate for less accessible surface and SSO deposits of about 22 per cent per year for the period 1992-2001. This paper emphasized that shoreline type plays a key role in determining SSO persistence. The geology of PWS is complex. Many of the shorelines where SSO persists have armouring layers composed of hard, dense clasts, such as the quartzite boulders and cobblestones that can protect SSO deposits. Eighteen years after the spill, persistent SSO deposits in PWS shorelines remain protected from tidal water-washing and biodegradation by a surface boulder/cobble armour and low sediment porosity. The SSO deposits are in a physical/chemical form and location where they do not pose a health risk to intertidal biological communities and animals. The surveys continue to substantiate that remaining SSO deposits in PWS continue to degrade and go away slowly. 37 refs., 5 tabs., 7 figs.

  15. Neural control of left ventricular contractility in the dog heart: synaptic interactions of negative inotropic vagal preganglionic neurons in the nucleus ambiguus with tyrosine hydroxylase immunoreactive terminals.

    Science.gov (United States)

    Massari, V J; Dickerson, L W; Gray, A L; Lauenstein, J M; Blinder, K J; Newsome, J T; Rodak, D J; Fleming, T J; Gatti, P J; Gillis, R A

    1998-08-17

    Recent physiological evidence indicates that vagal postganglionic control of left ventricular contractility is mediated by neurons found in a ventricular epicardial fat pad ganglion. In the dog this region has been referred to as the cranial medial ventricular (CMV) ganglion [J.L. Ardell, Structure and function of mammalian intrinsic cardiac neurons, in: J.A. Armour, J.L. Ardell (Eds.). Neurocardiology, Oxford Univ. Press, New York, 1994, pp. 95-114; B.X. Yuan, J.L. Ardell, D.A. Hopkins, A.M. Losier, J.A. Armour, Gross and microscopic anatomy of the canine intrinsic cardiac nervous system, Anat. Rec., 239 (1994) 75-87]. Since activation of the vagal neuronal input to the CMV ganglion reduces left ventricular contractility without influencing cardiac rate or AV conduction, this ganglion contains a functionally selective pool of negative inotropic parasympathetic postganglionic neurons. In the present report we have defined the light microscopic distribution of preganglionic negative inotropic neurons in the CNS which are retrogradely labeled from the CMV ganglion. Some tissues were also processed for the simultaneous immunocytochemical visualization of tyrosine hydroxylase (TH: a marker for catecholaminergic neurons) and examined with both light microscopic and electron microscopic methods. Histochemically visualized neurons were observed in a long slender column in the ventrolateral nucleus ambiguus (NA-VL). The greatest number of retrogradely labeled neurons were observed just rostral to the level of the area postrema. TH perikarya and dendrites were commonly observed interspersed with vagal motoneurons in the NA-VL. TH nerve terminals formed axo-dendritic synapses upon negative inotropic vagal motoneurons, however the origin of these terminals remains to be determined. We conclude that synaptic interactions exist which would permit the parasympathetic preganglionic vagal control of left ventricular contractility to be modulated monosynaptically by

  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. 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. "

  18. Effect of geometrical configuration of sediment replenishment on the development of bed form patterns in a gravel bed channel

    Science.gov (United States)

    Battisacco, Elena; Franca, Mário J.; Schleiss, Anton J.

    2016-04-01

    Dams interrupt the longitudinal continuity of river reaches since they store water and trap sediment in the upstream reservoir. By the interruption of the sediment continuum, the transport capacity of downstream stretch exceeds the sediment supply, thus the flow becomes "hungry". Sediment replenishment is an increasingly used method for restoring the continuity in rivers and for re-establishing the sediment regime of such disturbed river reaches. This research evaluates the effect of different geometrical configurations of sediment replenishment on the evolution of the bed morphology by systematic laboratory experiments. A typical straight armoured gravel reach is reproduced in a laboratory flume in terms of slope, grain size and cross section. The total amount of replenished sediment is placed in four identical volumes on both channel banks, forming six different geometrical configurations. Both alternated and parallel combinations are studied. Preliminary studies demonstrate that a complete submergence condition of the replenishment deposits is most adequate for obtaining a complete erosion and a high persistence of the replenished material in the channel. The response of the channel bed morphology to replenishment is documented by camera and laser scanners installed on a moveable carriage. The parallel configurations create an initially strong narrowing of the channel section. The transport capacity is thus higher and most of the replenished sediments exit the channel. The parallel configurations result in a more spread distribution of grains but with no clear morphological pattern. Clear bed form patterns can be observed when applying alternated configurations. Furthermore, the wavelength of depositions correspond to the replenishment deposit length. These morphological forms can be assumed as mounds. In order to enhance channel bed morphology on an armoured bed by sediment replenishment, alternated deposit configurations are more favourable and effective. The

  19. Inconsistency in 9 mm bullets: correlation of jacket thickness to post-impact geometry measured with non-destructive X-ray computed tomography.

    Science.gov (United States)

    Thornby, John; Landheer, Dirk; Williams, Tim; Barnes-Warden, Jane; Fenne, Paul; Norman, Daniel; Attridge, Alex; Williams, Mark A

    2014-01-01

    Fundamental to any ballistic armour standard is the reference projectile to be defeated. Typically, for certification purposes, a consistent and symmetrical bullet geometry is assumed, however variations in bullet jacket dimensions can have far reaching consequences. Traditionally, characteristics and internal dimensions have been analysed by physically sectioning bullets--an approach which is of restricted scope and which precludes subsequent ballistic assessment. The use of a non-destructive X-ray computed tomography (CT) method has been demonstrated and validated (Kumar et al., 2011 [15]); the authors now apply this technique to correlate bullet impact response with jacket thickness variations. A set of 20 bullets (9 mm DM11) were selected for comparison and an image-based analysis method was employed to map jacket thickness and determine the centre of gravity of each specimen. Both intra- and inter-bullet variations were investigated, with thickness variations of the order of 200 μm commonly found along the length of all bullets and angular variations of up to 50 μm in some. The bullets were subsequently impacted against a rigid flat plate under controlled conditions (observed on a high-speed video camera) and the resulting deformed projectiles were re-analysed. The results of the experiments demonstrate a marked difference in ballistic performance between bullets from different manufacturers and an asymmetric thinning of the jacket is observed in regions of pre-impact weakness. The conclusions are relevant for future soft armour standards and provide important quantitative data for numerical model correlation and development. The implications of the findings of the work on the reliability and repeatability of the industry standard V50 ballistic test are also discussed.

  20. 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.

  1. Historical geomorphic analysis (1932-2011) of a by-passed river reach in process-based restoration perspectives: The Old Rhine downstream of the Kembs diversion dam (France, Germany)

    Science.gov (United States)

    Arnaud, F.; Piégay, H.; Schmitt, L.; Rollet, A. J.; Ferrier, V.; Béal, D.

    2015-05-01

    The Old Rhine downstream of the Kembs diversion dam is one of the largest by-passed river reaches in the world (50 km). It offers a unique opportunity to study the morphological effects of by-passing and address physical and ecological restoration approaches in regulated rivers. We conduct a space-time analysis of channel adjustment over a period of 80 years (1932 to 2011). We examine planform changes (from aerial photographs), erosional and depositional patterns (from vertical profiles), sediment sizes within the active channel and the new established floodplain, and we date riparian vegetation encroachment. Results show that the Old Rhine exhibited rapid response to the completion of the by-passing scheme in the 1950s, with a 26% narrowing in median active channel width between 1956 and 2008, from vegetation encroachment on dewatered channel margins (mostly groyne fields). The narrowing was accompanied by overbank fine sediment deposition (~ 1.5 cm y- 1 aggradation since 1950) as well as slight bed degradation (~ 0.7 cm y- 1 since 1950). We found no downstream propagation of active channel narrowing over time, nor propagation of bed degradation. The channel was already significantly adjusted prior to the diversion scheme, following the nineteenth century river straightening and groyne construction. By-passing (dewatering) mainly provided new pioneer habitat for synchronous vegetation establishment and promoted channel stability by decreasing sediment transport owing to peak flow reduction. The morphological budget calculated over the past 20 years estimated a downstream output for coarse sediments at 16,000 m3 y- 1, with 80% originating from bed degradation and 20% from bank erosion, without significant inputs from upstream. The present-day morphodynamics remain sensitive to changes because of dynamic bed armouring (strategies for altered rivers. Recommended activities are gravel reintroduction with particle-sizes finer than the armoured river bed to enhance

  2. 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

  3. 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

  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. 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

  6. 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)

  7. 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.

  8. 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.

  9. 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

  10. 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).

  11. 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.

  12. 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.

  13. 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)

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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)

  19. 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.

  20. 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)

  1. 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)

  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. Las armaduras segmentadas (loricae segmentatae en los yacimientos romanos de la provincia de León: un estudio de conjunto

    Directory of Open Access Journals (Sweden)

    Aurrecoechea Fernández, Joaquín

    2007-12-01

    Full Text Available We analyze the unpublished discoveries of loricae segmentatae from León province. In that territory, all the recognizable categories are attested. Sites from León offer the most advanced late chronology in the whole Empire, regarding armours to “Corbridge” and “Newstead” types, fact corroborated in diverse excavations. It will be necessary to consider when we date these loricae segmentatae in the future.Se estudian los abundantes restos inéditos de loricae segmentatae procedentes de la provincia de León, donde se documentan todas las variantes de estas piezas conocidas hasta el momento. Los yacimientos leoneses han proporcionado la cronología final más avanzada de todo el Imperio respecto a las armaduras “Corbridge” y a las corazas “Newstead”, dato corroborado en diversas excavaciones y que deberá ser tenido en cuenta a la hora de fechar estas categorías en el futuro.

  4. 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.

  5. 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)

  6. 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

  7. 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)

  8. [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

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. Taikomosios emblemos Vilniaus bažnyčiose ir jų literatūriniai šaltiniai | Applied emblems in Vilnius churches and their literary sources

    Directory of Open Access Journals (Sweden)

    Veronika Gerliakienė

    2005-01-01

    Full Text Available This article deals with applied emblems found in open Vilnius churches, decorated in the 16th–18th centuries. There are twenty–seven decorative emblems placed on the ceilings and arches of the churches. The verbal part of these emblems, called inscriptio or lemma, is the object of the article.In the 16th century when European literature was enriched with a new genre of emblem, the artists and craftsmen began to use these emblems as a decorative element in their works such as jewelry, armours, carpets, bells, plates, furniture etc. The same phenomenon is seen in the decoration of Vilnius churches.Our research proved that people who worked out the idea of the decoration of the church used two sources for decorative emblems – the Bible (a short quotation from the Bible was used as an inscription and well-known literary emblems. Speaking about the latter source, some decorative emblems are exact copies of the works of famous 16th century writers, where inscription, icon and concept are taken without any changes. Others show variations on popular literary emblems of that time. Modifications could appear both in verbal and in visual part, thus entirely changing the idea of the emblem.

  15. 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)

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

    Energy Technology Data Exchange (ETDEWEB)

    Manes, A., E-mail: andrea.manes@polimi.it; Pagani, M.; Saponara, M.; Mombelli, D.; Mapelli, C.; Giglio, M.

    2014-07-01

    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.

  17. 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

  18. 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.)

  19. 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.

  20. 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

  1. 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

  2. A survey of scale insects (Hemiptera: Coccoidea occurring on olives in Tunisia

    Directory of Open Access Journals (Sweden)

    Rramzi Mansour

    2011-09-01

    Full Text Available A survey performed in 2009 within 52 Tunisian olive groves, located in 17 different olive-growing sites, revealed the occurrence of six scale insects on olives. The identified species were: the armoured scales Aspidiotus nerii Bouché, Lepidosaphes ulmi (L., and Parlatoria oleae (Colvée, the soft scales Saissetia oleae (Olivier and Filippia follicularis (Targioni Tozzetti and the mealybug species Peliococcus cycliger (Leonardi. The soft scale F. follicularis is a new record for the Tunisian insect fauna. A mong these species, S. oleae was the predominant scale insect occurring throughout olive groves of northeastern Tunisia, whereas the mealybug P. cycliger was by far the most abundant species within olives groves of the Northwest region of Tunisia. However, P. oleae was the least abundant species, being present in only one olive-growing site in northeastern Tunisia. L arvae of the noctuid moth Eublemma scitula (Rambur were reported feeding on S. oleae and the coccinellid Chilocorus bipustulatus L . was found feeding on both S. oleae and A. nerii. The two hymenopteran species Scutellista cyanea Motschulsky and Metaphycus spp. were recorded as the main parasitoids of S. oleae.

  3. 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

    2016-05-30

    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.

  4. 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.

  5. 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.

  6. 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

  7. 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...... and regular ping-pong balls the size 3.6cm in the other. The orbital-motion-amplitude-to-roughness ratio at the bed was rather small, in the range a/ks=0.6-3. The mean and turbulence properties of the boundary-layer flow were measured. Various configurations of the roughness elements were used in the ping...... for small values of a/ks. The results further show that the phase lead of the bed friction velocity over the surface elevation does not seem to change radically with a/ks, and found to be in the range 12°-23°. Furthermore the results show that the boundary-layer turbulence also is not extremely sensitive...

  8. 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...

  9. 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

  10. Oxidation behaviour of bulk W-Cr-Ti alloys prepared by mechanical alloying and HIPing

    Energy Technology Data Exchange (ETDEWEB)

    García-Rosales, C., E-mail: cgrosales@ceit.es [CEIT and Tecnun (University of Navarra), E-20018 San Sebastian (Spain); López-Ruiz, P.; Alvarez-Martín, S.; Calvo, A.; Ordás, N. [CEIT and Tecnun (University of Navarra), E-20018 San Sebastian (Spain); Koch, F.; Brinkmann, J. [Max-Planck-Institut für Plasmaphysik (IPP), EURATOM Association, D-85748 Garching (Germany)

    2014-10-15

    Self-passivating tungsten based alloys are expected to provide a major safety advantage compared to pure tungsten when used as first wall armour of future fusion reactors, due to the formation of a protective oxide scale, preventing the formation of volatile and radioactive WO{sub 3} in case of a loss of coolant accident with simultaneous air ingress. In this work results of isothermal oxidations tests at 800 and 1000 °C on bulk alloy WCr12Ti2.5 performed by thermogravimetric analysis (TGA) and by exposure to flowing air in a furnace are presented. In both cases a thin, dense Cr{sub 2}O{sub 3} layer is found at the outer surface, below which a Cr{sub 2}WO{sub 6} scale and Ti{sub 2}CrO{sub 5} layers alternating with WO{sub 3} are formed. The Cr{sub 2}O{sub 3}, Cr{sub 2}WO{sub 6} and Ti{sub 2}CrO{sub 5} scales act as protective barriers against fast inward O{sup 2−} diffusion. The oxidation kinetics seems to be linear for the furnace exposure tests while for the TGA tests at 800 °C the kinetics is first parabolic, transforming into linear after an initial phase. The linear oxidation rates are 2–3 orders of magnitude lower than for pure W.

  11. Initial results from the rebuilt EXTRAP T2R RFP device

    Science.gov (United States)

    Brunsell, P. R.; Bergsåker, H.; Cecconello, M.; Drake, J. R.; Gravestijn, R. M.; Hedqvist\\ad{2 }, A.; Malmberg, J.-A.

    2001-11-01

    The EXTRAP T2R thin shell reversed-field pinch (RFP) device has recently resumed operation after a major rebuild including the replacement of the graphite armour with molybdenum limiters, a fourfold increase of the shell time constant, and the replacement of the helical coil used for the toroidal field with a conventional solenoid-type coil. Wall-conditioning using hydrogen glow discharge cleaning was instrumental for successful RFP operation. Carbon was permanently removed from the walls during the first week of operation. The initial results from RFP operation with relatively low plasma currents in the range Ip = 70-100 kA are reported. RFP discharges are sustained for more than three shell times. Significant improvements in plasma parameters are observed, compared to operation before the rebuild. There is a substantial reduction in the carbon impurity level. The electron density behaviour is more shot-to-shot reproducible. The typical density is ne = 0.5-1×1019 m-3. Monitors of Hα line radiation indicate that the plasma wall interaction is more toroidally symmetric and that there is less transient gas release from the wall. The minimum loop voltage is in the range Vt = 28-35 V, corresponding to a reduction by a factor of two to three compared to the value before the rebuild.

  12. Expression of Wnt signaling skeletal development genes in the cartilaginous fish, elephant shark (Callorhinchus milii).

    Science.gov (United States)

    D'Souza, Damian G; Rana, Kesha; Milley, Kristi M; MacLean, Helen E; Zajac, Jeffrey D; Bell, Justin; Brenner, Sydney; Venkatesh, Byrappa; Richardson, Samantha J; Danks, Janine A

    2013-11-01

    Jawed vertebrates (Gnasthostomes) are broadly separated into cartilaginous fishes (Chondricthyes) and bony vertebrates (Osteichthyes). Cartilaginous fishes are divided into chimaeras (e.g. ratfish, rabbit fish and elephant shark) and elasmobranchs (e.g. sharks, rays and skates). Both cartilaginous fish and bony vertebrates are believed to have a common armoured bony ancestor (Class Placodermi), however cartilaginous fish are believed to have lost bone. This study has identified and investigated genes involved in skeletal development in vertebrates, in the cartilaginous fish, elephant shark (Callorhinchus milii). Ctnnb1 (β-catenin), Sfrp (secreted frizzled protein) and a single Sost or Sostdc1 gene (sclerostin or sclerostin domain-containing protein 1) were identified in the elephant shark genome and found to be expressed in a number of tissues, including cartilage. β-catenin was also localized in several elephant shark tissues. The expression of these genes, which belong to the Wnt/β-catenin pathway, is required for normal bone formation in mammals. These findings in the cartilaginous skeleton of elephant shark support the hypothesis that the common ancestor of cartilaginous fishes and bony vertebrates had the potential for making bone.

  13. 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.

  14. 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.

  15. The ecology of an adaptive radiation of three-spined stickleback from North Uist, Scotland.

    Science.gov (United States)

    Magalhaes, Isabel S; D'Agostino, Daniele; Hohenlohe, Paul A; MacColl, Andrew D C

    2016-09-01

    There has been a large focus on the genetics of traits involved in adaptation, but knowledge of the environmental variables leading to adaptive changes is surprisingly poor. Combined use of environmental data with morphological and genomic data should allow us to understand the extent to which patterns of phenotypic and genetic diversity within a species can be explained by the structure of the environment. Here, we analyse the variation of populations of three-spined stickleback from 27 freshwater lakes on North Uist, Scotland, that vary greatly in their environment, to understand how environmental and genetic constraints contribute to phenotypic divergence. We collected 35 individuals per population and 30 abiotic and biotic environmental parameters to characterize variation across lakes and analyse phenotype-environment associations. Additionally, we used RAD sequencing to estimate the genetic relationships among a subset of these populations. We found a large amount of phenotypic variation among populations, most prominently in armour and spine traits. Despite large variation in the abiotic environment, namely in ion composition, depth and dissolved organic Carbon, more phenotypic variation was explained by the biotic variables (presence of predators and density of predator and competitors), than by associated abiotic variables. Genetic structure among populations was partly geographic, with closer populations being more similar. Altogether, our results suggest that differences in body shape among stickleback populations are the result of both canalized genetic and plastic responses to environmental factors, which shape fish morphology in a predictable direction regardless of their genetic starting point. PMID:27374399

  16. 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。

  17. 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

  18. Сравнительная оценка силовых установок БТР-4 с различными двигателями

    OpenAIRE

    Бобер, А. В.; Зарянов, В. А.; Крот, С. Г.; Кузьминский, В. А.; Федянин, А. В.

    2014-01-01

    В статье представлена сравнительная оценка моторно-трансмиссионных отделений БТР-4, разработанных ГП "ХКБМ им. А. А. Морозова", по мощностным и качественным показателям, основанных на экспериментальных данных. The article shows comparative estimate of power pack of armoured vehicle, designed by SE KMDB, according to power and qualitative indexes. Estimate methods of perfection of power pack are showed in this article too....

  19. 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.

  20. 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.

  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. 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

  3. 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.

  4. 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

  5. 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

  6. Combat Helmets and Blast Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Duncan Wallace

    2012-01-01

    Full Text Available Background: The conflicts in Iraq and Afghanistan and the prominence of traumatic brain injury (TBI, mostly from improvised explosive devices, have focused attention on the effectiveness of combat helmets. Purpose: This paper examines the importance of TBI, the role and history of the development of combat helmets, current helmet designs and effectiveness, helmet design methodology, helmet sensors, future research and recommendations. Method: A literature review was conducted using search terms – combat helmets, traumatic brain injury, concussion, Iraq, Afghanistan and helmet sensors, searching PubMed, MEDLINE, ProQuest and Google Scholar. Conclusions: At present, no existing helmet is able to fully protect against all threats faced on the battlefield. The prominence of traumatic brain injury from improvised explosive devices in the current conflicts in Iraq and Afghanistan has highlighted the limitations in knowledge about blast and how to provide protection from it. As a result, considerable research is currently occurring in how to protect the head from blast over-pressure. Helmet sensors may provide valuable data. Some new combat helmets may be able to protect against rifle rounds, but may result in injuries occurring behind body armour. Optimal combat helmet design requires a balance between the need for protection from trauma and the comfort and practicality of the helmet for the user to ensure the best outcomes.

  7. 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.

  8. 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)

  9. 坦克装甲车辆装甲防护发展研究%Armor Protection Development of Tank & Armored Vehicle

    Institute of Scientific and Technical Information of China (English)

    房凌晖; 郑翔玉; 马丽; 汪伦根

    2014-01-01

    This article first discusses the advances and the applications of main armor materials,including armour steel,aluminum alloys,titanium alloy,ceramic and composite materials. Then,the basical theory and research status of some typical armor protection technologies are introduced in detail,such as explosive reactive armor,composite armor,grille armor,electromagnetic armor and so on. And on this basis,the future development trend of armor protection technology is also discussed,which is important to improve the protection ability and viability of armored vehicle.%阐述了装甲钢、铝合金、钛合金、陶瓷和复合材料等主流装甲防护材料的研究现状和应用情况,并对爆炸反应装甲、复合装甲、格栅装甲和电磁装甲等几种典型装甲防护技术的基本原理和研究现状进行了介绍;分析了未来装甲防护技术的发展方向和趋势,对提高装甲车辆的防护能力和战场生存能力具有重要意义。

  10. 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

  11. 医院绩效管理对员工行为影响的实证分析%An Empirical Analysis of the Inflience of Hospital Performance Management on Employee Behavior

    Institute of Scientific and Technical Information of China (English)

    刘娜; 韩靖; 薛淑红; 高德凤

    2016-01-01

    Objective To explore the hospital performance management affect employee behavior. Methods In November 2015 to December 2015 in more areas of the questionnaire survey to a total of 15 hospitals to the hospital, the questionnaire survey to relevant employees including the clear goal, the goal to participate in the work, support and feedback, performance salary, performance appraisal, reward performance, job satisfaction, organizational commitment, and other related content, depending on the type of hospital, grade, comparing different hospital performance management, to provide Suggestions for hospital performance management. Results The clear degree, the goals of state-owned hospital staff job satisfaction signifi-cantly higher compared with civilian battalion hospital, P < 0.05. Civilian battalion hospital employees job support and feedback, performance salary, performance bonus and significantly higher than the state-owned hospital, P < 0.05). 3 ar-mour hospital specific goals and organizational commitment significantly higher compared with dimethyl hospital, P< 0.05). 3 armour hospital performance evaluation, job satisfaction, organizational commitment significantly higher compared with di-ethyl hospital, P<0.05). Dimethyl hospital organizational commitment significantly higher compared with diethyl hospital, P< 0.05. Conclusion Different types of hospitals, the employee behavior under different grade hospital performance manage-ment is put in bigger difference, can according to the ac-tual situation hospital targeted performance management measures are put forward.%目的:探讨医院绩效管理对员工行为的影响。方法于2015年11月—2015年12月间对多地区共15所医院进行问卷调查,对医院相关员工进行问卷调查,包括目标明确、目标参与、工作支持、工作反馈、绩效工资、绩效考核、绩效奖励、工作满意度、组织承诺等相关内容,根据医院类型、等级状况,对比不同医院绩效管

  12. 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

  13. 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

  14. Coastal changes in the Sendai area from the impact of the 2011 Tōhoku-oki tsunami: Interpretations of time series satellite images, helicopter-borne video footage and field observations

    Science.gov (United States)

    Tappin, David R.; Evans, Hannah M.; Jordan, Colm J.; Richmond, Bruce; Sugawara, Daisuke; Goto, Kazuhisa

    2012-12-01

    A combination of time-series satellite imagery, helicopter-borne video footage and field observation is used to identify the impact of a major tsunami on a low-lying coastal zone located in eastern Japan. A comparison is made between the coast protected by armoured 'engineered' sea walls and the coast without. Changes are mapped from before and after imagery, and sedimentary processes identified from the video footage. The results are validated by field observations. The impact along a 'natural' coast, with minimal defences, is erosion focussed on the back beach. Along coasts with hard engineered protection constructed to defend against erosion, the presence of three to six metre high concrete-faced embankments results in severe erosion on their landward faces. The erosion is due to the tsunami wave accelerating through a hydraulic jump as it passes over the embankment, resulting in the formation of a ditch into which the foundations collapse. Engineered coastal defences are thus found to be small defence against highly energetic tsunami waves that overtop them. There is little erosion (or sedimentation) of the whole beach, and where active, it mainly forms V-shaped channels. These channels are probably initiated during tsunami inflow and then further developed during tsunami backflow. Tsunami backflow on such a low lying area takes place energetically as sheet flow immediately after tsunami flooding has ceased. Subsequently, when the water level landward of the coastal dune ridges falls below their elevation, flow becomes confined to rivers and breaches in the coast formed during tsunami inflow. Enigmatic, short lived, 'strand lines' are attributed to the slow fall of sea level after such a major tsunami. Immediately after the tsunami coastal reconstruction begins, sourced from the sediment recently flushed into the sea by tsunami backflow.

  15. Coupling Landform Evolution and Soil Pedogenesis - Initial Results From the SSSPAM5D Model

    Science.gov (United States)

    Willgoose, G. R.; Welivitiya, W. D. D. P.; Hancock, G. R.; Cohen, S.

    2015-12-01

    Evolution of soil on a dynamic landform is a crucial next step in landscape evolution modelling. Some attempts have been taken such as MILESD by Vanwalleghem et al. to develop a first model which is capable of simultaneously evolving both the soil profile and the landform. In previous work we have presented physically based models for soil pedogenesis, mARM and SSSPAM. In this study we present the results of coupling a landform evolution model with our SSSPAM5D soil pedogenesis model. In previous work the SSSPAM5D soil evolution model was used to identify trends of the soil profile evolution on a static landform. Two pedogenetic processes, namely (1) armouring due to erosion, and (2) physical and chemical weathering were used in those simulations to evolve the soil profile. By incorporating elevation changes (due to erosion and deposition) we have advanced the SSSPAM5D modelling framework into the realm of landscape evolution. Simulations have been run using elevation and soil grading data of the engineered landform (spoil heap) at the Ranger Uranium Mine, Northern Territory, Australia. The results obtained for the coupled landform-soil evolution simulations predict the erosion of high slope areas, development of rudimentary channel networks in the landform and deposition of sediments in lowland areas, and qualitatively consistent with landform evolution models on their own. Examination of the soil profile characteristics revealed that hill crests are weathering dominated and tend to develop a thick soil layer. The steeper hillslopes at the edge of the landform are erosion dominated with shallow soils while the foot slopes are deposition dominated with thick soil layers. The simulation results of our coupled landform and soil evolution model provide qualitatively correct and timely characterization of the soil evolution on a dynamic landscape. Finally we will compare the characteristics of erosion and deposition predicted by the coupled landform-soil SSSPAM

  16. 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.

  17. 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.

  18. 8种杀菌剂对雪莲果褐斑病的室内毒力测定%Toxicity Determination of 8 Fungicides against Brown Spot of Yacon in Laboratory

    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.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. 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)

  8. 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)

  9. 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)

  10. Correction of slight and moderate cup ear malformation by using tumbling cartilage flap%缝卷软骨瓣法矫正轻中度杯状耳畸形

    Institute of Scientific and Technical Information of China (English)

    于晓波; 蒋海越; 庄洪兴; 潘博; 赵延勇; 刘磊

    2011-01-01

    目的 探讨缝卷软骨瓣法矫正轻中度杯状耳畸形的疗效.方法 于耳后上部设计一2.5cm×0.5cm梭形切口.距耳轮0.5cm处纵向切开耳软骨,将耳软骨层潜行向下分离,将分离的耳软骨瓣向后与耳甲腔软骨反卷缝缝合,形成形态正常的对耳轮上脚,维持正常的外耳形态.结果 本组患者12例(14只耳),其中双侧者2例,术后随访3~12个月,效果良好.结论 缝卷软骨瓣法是矫正轻中度杯状耳畸形的一种简单、有效的手术方法.%Objective To explore the curative effect of tumbling cartilage flap on correction of cup ear malformation. Methods A 2. 5 cm × 0. 5 cm fusiform incision was designed on the superior postauricular part.Ear cartilage was cut in the position 0. 5 cm away from the edge of the helix, then the layer of cartilage was dissected downwards , the ear flap with cartilage was reflexed and sutured reversdy with the ear armour cavity cartilage to form the normal upper crus of antihelix to maintain the normal auricle shape. Results After 3 to 12 months follow-up on 12 cases ( 14 ears) , all cases were satisfied with the stable appearance. Conclusion The method is simple and effective for the correction of cup ear malformation.

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

    Energy Technology Data Exchange (ETDEWEB)

    López-Ruiz, P.; Ordás, N.; Iturriza, I. [CEIT and Tecnun (University of Navarra), E-20018 San Sebastian (Spain); Walter, M.; Gaganidze, E. [Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen (Germany); Lindig, S.; Koch, F. [Max-Planck-Institut für Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); García-Rosales, C., E-mail: cgrosales@ceit.es [CEIT and Tecnun (University of Navarra), E-20018 San Sebastian (Spain)

    2013-11-15

    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 WO{sub 3}. 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){sub 5}Si{sub 3}; 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.

  12. 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)

  13. Eco-engineered rock pools: a concrete solution to biodiversity loss and urban sprawl in the marine environment

    Science.gov (United States)

    Firth, Louise B.; Browne, Keith A.; Knights, Antony M.; Hawkins, Stephen J.; Nash, Róisín

    2016-09-01

    In coastal habitats artificial structures typically support lower biodiversity and can support greater numbers of non-native and opportunistic species than natural rocky reefs. Eco-engineering experiments are typically trialed to succeed; but arguably as much is learnt from failure than from success. Our goal was to trial a generic, cost effective, eco-engineering technique that could be incorporated into rock armouring anywhere in the world. Artificial rock pools were created from manipulated concrete between boulders on the exposed and sheltered sides of a causeway. Experimental treatments were installed in locations where they were expected to fail and compared to controls installed in locations in which they were expected to succeed. Control pools were created lower on the structure where they were immersed on every tidal cycle; experimental pools were created above mean high water spring tide which were only immersed on spring tides. We hypothesised that lower and exposed pools would support significantly higher taxon and functional diversity than upper and sheltered pools. The concrete pools survived the severe winter storms of 2013/14. After 12 months, non-destructive sampling revealed significantly higher mean taxon and functional richness in lower pools than upper pools on the exposed side only. After 24 months the sheltered pools had become inundated with sediments, thus failing to function as rock pools as intended. Destructive sampling on the exposed side revealed significantly higher mean functional richness in lower than upper pools. However, a surprisingly high number of taxa colonised the upper pools leading to no significant difference in mean taxon richness among shore heights. A high number of rare taxa in the lower pools led to total taxon richness being almost twice that of upper pools. These findings highlight that even when expected to fail concrete pools supported diverse assemblages, thus representing an affordable, replicable means of

  14. 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

  15. 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)

  16. Мощностные характеристики и показатели качества силовых установок бронетранспортеров, разработанных в КП ХКБМ

    OpenAIRE

    Возгрин, Ю. В.; Герасименко, В. И.; Золотуха, В. Н.; Кузьминский, В. А.; Крот, С. Г.

    2012-01-01

    У статті наведена порівняльна оцінка моторно-трансмісійних відділень БТР, розроблених у КП ХКБМ ім. О. О. Морозова, за показниками потужності та якості що ґрунтуються на експериментальних даних; наведені методи оцінки досконалості моторно-трансмісійних відділень. The article shows comparative estimate of power pack of armoured vehicle, designed by SOE KhMMBDB, according to power and qualitative indexes. Estimate methods of perfection of power pack are showed in this article too....

  17. 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.

  18. 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.

  19. 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.

  20. Children and cycle helmets -- the case against.

    Science.gov (United States)

    McCarthy, M

    1996-03-01

    Much of the literature on child cycling accidents appears to blame the child as a victim, as though children's activities of playing and travelling were somehow wrong and that children are at fault when an adult drives a car over them. This adult-centred approach then leads to the idea that children should protect themselves with helmets, and that they are to blame if they are injured. However, adults who continue to hold the fantasy that helmets might be of value should know that the British Standard for cycle helmets protects only in a vertical fall of 1 m -- certainly not motor vehicle crashes. Thicker motor cycle helmets would give better protection but, of course, are heavier (and therefore unsaleable). Yet even with compulsory wearing helmets, more motor cyclists still die of head injuries than pedal cyclists. In the Newcastle study, five times as many child pedestrians died of road accidents as child cyclists. Convinced helmeteers should recommend all children playing or travelling in the streets to wear helmets (presumably heavy motor-cycle helmets). Slightly more sceptical proponents might prefer half of them -- in a randomized controlled trial. Car driving appears to have as serious health consequences as tobacco, alcohol and drugs, and to be as addictive (McCarthy 1992). Helmets are similar to filters in cigarettes -- they give the illusion of safety to both consumer and producer of the product, but the illusion is fatal. Yet, for their cardiovascular and mental health, children should have the freedom to cycle in safety around where they live. A profound change in the habits of adults is needed, rather than suits of armour for children.

  1. 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

  2. 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

  3. Monitoring the Methane Hydrate Dissociation by the Offshore Methane Hydrate Production Tests using Multi-component Seismic

    Science.gov (United States)

    Asakawa, Eiichi; Hayashi, Tsutomu; Tsukahara, Hitoshi; Takahashi, Hiroo; Saeki, Tatsuo

    2013-04-01

    We developed a new OBC (Ocean Bottom Cable), named as 'DSS' (Deep-sea Seismic System). The sensor has 3-component accelerometer and a hydrophone applicable for four-component (4C) seismic survey. Using the DSS, the methane hydrate dissociation zone will be tried to be monitored at the water depth of around 1000m during JOGMEC offshore methane hydrate production test in early 2013. Before the DSS, we had developed the RSCS (Real-time Seismic Cable System) with 3-component gimbaled geophones, and carried out a reflection seismic survey in the Nankai Trough in 2006. Referring this successful survey, we improved the RSCS to the DSS. The receiver size is reduced to 2/3 and the receiver case has a protective metallic exterior and the cable is protected with steel-screened armouring, allowing burial usage using ROV for sub-seabed deployment at the water depth up to 2000m. It will realize a unique survey style that leaves the system on the seabed between pre-test baseline survey and post-test repeated surveys, which might be up to 6 months. The fixed location of the receiver is very important for time-lapse monitoring survey. The DSS has totally 36 sensors and the sensor spacing is 26.5m. The total length is about 1km. We carried out the pre-test baseline survey between off Atsumi and Shima-peninsula in August, 2012.We located the DSS close to the production test well. The nearest sensor is 63m apart from the well. A newly developed real-time 3-D laying simulation system consisting of ADCP (Acoustic Doppler Current Profiler), transponders attached to the DSS, and real-time 3-D plotting system for transponder locations have been adopted. After we laid the cable, we buried the DSS using ROV (Remotely Operated Vehicle). The baseline survey included 2D/3D seismic surveys with shooting vessel and cable laying/observation ship. The resultant 2D section and 3D volume shows the good quality to delineate the methane hydrate concentrated zone. After the baseline survey, we have left

  4. 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.

  5. The Concept of Cosmic Tree in Armenian and Iranian Cosmologies

    Science.gov (United States)

    Farmanyan, S. V.; Mickaelian, A. M.

    2016-09-01

    Cosmic Tree or Tree of Life is a common motif in various world theologies, mythologies, and philosophies. In the present study we focus on Armenian and Iranian Cosmic Tree. In ancient Armenia, the Tree of Life (Կենաց Ծառ) is a religious symbol and is drawn on walls of fortresses and carved on the armour of warriors. According to ancient Armenians the center of the Universe is located at the crown of the tree or the column, which is the closest to the sky. We explore the idea of cosmic tree in the riddles, prayers, medieval rituals and miniatures. In the riddles, the tree mostly symbolizes the celestial phenomena (Sun, Stars, and Heavens), different units of time (years, months, weeks, days, and seasons), the people, Jerusalem, the apostles and Jesus Christ. The branches of the tree were equally divided on the right and left sides of the stem, with each branch having one leaf, and one leaf on the apex of the tree. Servants stood on each side of the tree with one of their hands up as if they are taking care of the tree. In pre-Islamic Persian mythology, the Gaokerena world tree is a large, sacred Haoma tree which bears all seeds. Ahriman created a frog to invade the tree and destroy it, aiming at preventing all trees from growing on the Earth. As a reaction, God (Ahura Mazda) created two kar fish staring at the frog to guard the tree. The concept of world tree in Persian Mythology is very closely related to the concept of the Tree of Life. Another related issue in ancient mythology of Iran is the myth of Mashya and Mashyane, two trees who were the ancestors of all living beings. This myth can be considered as a prototype for the creation myth where living beings are created by Gods (who have human forms). We come to the conclusion that in both cultures, no matter of the present different religions, the perception of Cosmic Tree is interconnected to the life on our planet and served as a metaphor for common descent in the evolutionary sense.

  6. The dynamics of a coupled soilscape-landscape evolution model

    Science.gov (United States)

    Welivitiya, Dimuth; Willgoose, Garry; Hancock, Greg

    2016-04-01

    In this study we present results obtained from a landform evolution model coupled with SSSPAM5D soilscape evolution model. This presentation will show a number of computer animations with this coupled model using a range of widely accepted soil profile weathering models, and erosion/armouring models. The animations clearly show that subtle changes in process can result in dramatic changes in long-term equilibrium hillslope and soilscape form. We will discuss the reasons for these differences, arguing from the various mathematical and physical assumptions modelled, and infer how observed hillslope form may provide identifiable (and perhaps quantifiable) landform and soilscape signatures of landscape and soilscape process, and in particular the coupling between the landscape and the soilscape. Specifically we have simulated soilscapes using 3 depth dependent weathering functions: 1) Exponential, 2) Humped and 3) Reversed exponential. The Exponential weathering function simulates physical weathering due to thermal effects, and the weathering rate exponentially decreases with depth. The Humped function simulates chemical and/or physical weathering with moisture feedbacks, where the highest weathering rate is at a finite depth below the surface and exponentially declines with depth. The Reversed exponential function simulates chemical weathering, and the highest weathering rate is at the soil-saprolite interface and exponentially decreases both above and below the interface. Both the Humped and Reversed exponential functions can be used as approximations to chemical weathering as they can be derived analytically by solving widely accepted geochemical weathering equations. The Humped function can arise where the weathering fluid is introduced at the top of the soil profile (e.g. rainfall equilibrated with carbon dioxide in the atmosphere), while the Reversed exponential can be derived when carbon dioxide is generated within the profile (e.g. by biodegradation of soil

  7. 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

  8. 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

  9. 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

  10. Cockroaches Allergens Trigger Asthma Prevention Study%蟑螂过敏原引发哮喘的防治研究

    Institute of Scientific and Technical Information of China (English)

    孙金; 张锡平; 赵庆武

    2011-01-01

    目的:了解蟑螂过敏原引发哮喘的作用机制,探寻蟑螂引发哮喘的防治方法.方法:对全市8家医院的呼吸科,儿科的哮喘病例80例进行问卷调奁和蟑螂抗原皮肤点刺试验.结果:哮喘患者对蟑螂抗原的反应性的相关性是显著的,其与阳性也是显著相关的(P<0.001),其阳性比率为40.0%,成人阳性比率为45.0%,儿童阳性比率为35.0%.男性阳性比率为56.25%,女性阳性比率为47.5%.结论:蟑螂是哮喘患者主要变应原之一,一般成人的阳性比率比儿童高,男性比女性高.免疫治疗和灭蟑是蟑螂过敏原引发哮喘主要有效的防治方法.%Objective:Understand cockroach allergens trigger asthma mechanism of action,and explore cockeroach trigger astma and the control.Metheods:the 83 armour hospital,pediatrics and an allergy clinic asthma cases 80 cases of questionnaire and cockroach antigen skin prick test.Results:Asthma patients to cockroach antigen reactive correlation is remarkable, its and positive is also significant(P<0.001),its positive 40.0%,adult positive ratio fot ratio for accounting for 36.0%,children positive 35.0%,male ratio fot positive ratio for 56.25%,women postive ratio for 47.5%.Concusion:Cockroaches are asthma patients main allergens,one of the positive ratio than the average adult children high,high males than females.Immune therapy and destroy Zhang is a cockroach allergens trigger asthma main effective prevention methods.

  11. 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

  12. 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

  13. 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

  14. 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

  15. Heterogeneous microchemistry between CdSO{sub 4} and CaCO{sub 3} particles under humidity and liquid water

    Energy Technology Data Exchange (ETDEWEB)

    Falgayrac, Guillaume, E-mail: guillaume.falgayrac@univ-lille2.fr [Laboratoire de Spectrochimie IR et Raman, UMR-CNRS 8516, Bât. C5 Université de Lille I, F-59655 Villeneuve d’Ascq Cedex (France); UDSL, Physiopathologie des Maladies Osseuses et Inflammatoires EA4490, IMPRT-IFR114, F-59000 Lille (France); Sobanska, Sophie; Brémard, Claude [Laboratoire de Spectrochimie IR et Raman, UMR-CNRS 8516, Bât. C5 Université de Lille I, F-59655 Villeneuve d’Ascq Cedex (France)

    2013-03-15

    Highlights: ► Raman analysis of chemical reactions between CdSO{sub 4} and CaCO{sub 3} particles. ► Under humid air no changes of morphology and chemical composition were observed. ► Condensation of liquid water generates an insoluble CdCO{sub 3} layer on CaCO{sub 3} surface. ► Addition of water previously equilibrated with CaCO{sub 3} generates CdCO{sub 3} and CaSO{sub 4}. -- Abstract: Laboratory experiments using in situ Raman imaging combined with ex situ TOF-S-SIMS demonstrate the behavior of CdSO{sub 4}·8/3H{sub 2}O microparticles in contact with {101"¯4} CaCO{sub 3} (calcite) surface under three different experimental conditions representative of unpolluted atmosphere. The contact of CdSO{sub 4}·8/3H{sub 2}O particles with CaCO{sub 3} surface in humid air (RH ∼ 40–80%) does not induce any chemical reaction. In contrast, the condensation of a water drop on CdSO{sub 4}·8/3H{sub 2}O/CaCO{sub 3} interface causes the free dissolution of CdSO{sub 4}·8/3H{sub 2}O particle in the drop. A CdSO{sub 4}·8/3H{sub 2}O microcrystal is reformed after gentle drying with a CdSO{sub 4}·H{sub 2}O coating of the CaCO{sub 3} surface. The TOF-S-SIMS image of the CaCO{sub 3} surface provides evidence of a thin layer corresponding probably to insoluble coating of CdCO{sub 3} (otavite) or Cd{sub x}Ca{sub 1−x}CO{sub 3} solid solution at the liquid–solid interface. This layer armours the CaCO{sub 3} from further dissolution and stops the reaction. The deposition of CdSO{sub 4}·8/3H{sub 2}O particle in water drop previously in contact with CaCO{sub 3} for a long time generates CdCO{sub 3} small rhombohedral crystals while gentle drying provokes the crystallization of bar shape crystals of CaSO{sub 4}·2H{sub 2}O (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.

  16. Linkages between ocean circulation, heat uptake and transient warming: a sensitivity study

    Science.gov (United States)

    Pfister, Patrik; Stocker, Thomas

    2016-04-01

    . Lett., 41, 7306-7313 Rose, B. E. J., K. C. Armour, D. S. Battisti, N. Feldl, and D. D. B. Koll (2014), The dependence of transient climate sensitivity and radiative feedbacks on the spatial pattern of ocean heat uptake, Geophys. Res. Lett., 41, 1071-1078 Winton M., K. Takahashi and I. M. Held (2010), Importance of ocean heat uptake efficacy to transient climate change, J. Clim., 23, 2333-44 Winton, M., S. M. Griffies, B. Samuels, J. L. Sarmiento and T. L. Frölicher (2013) Connecting changing ocean circulation with changing climate, J. Clim., 26, 2268-78

  17. 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

  18. 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

  19. 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

  20. 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

  1. The need to go beyond analysis in making risk-based decisions

    Energy Technology Data Exchange (ETDEWEB)

    Ahearne, J.F. [The Sigma XI Center, Research Triangle Park, NC (United States)

    1999-12-01

    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 beenall 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

  2. 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.

  3. WIDE-BLAD AXES «BALTA» FROM THE COLLECTION OF THE OMSK STATE HISTORY MUSEUM

    Directory of Open Access Journals (Sweden)

    Leonid Aleksandrovich Bobrov

    2015-01-01

    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.

  4. 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

  5. Application and Effect of Large-scale Inspection on Power Lines by Using Large Unmanned Helicopter in Guangdong Power Grid%广东电网大型无人直升机电力线路规模化巡检应用及效果

    Institute of Scientific and Technical Information of China (English)

    钱金菊; 麦晓明; 王柯; 易琳; 彭向阳; 饶章权

    2016-01-01

    This paper introduces self-developed large unmanned helicopter multi-sensor full automatic inspection system for power lines and states large-scale inspection scheme for parts of typical running lines of Guangdong power grid and corre-sponding results. This system uses combined inspection mode of unmanned helicopter channel inspection and detailed inspec-tion which could carry out multi-sensor and multi-dimensional synchronous detection and united diagnosis on channel envi-ronment,safe distance,abnormal heating and discharge of power transmission lines as well as equipment appearances and structural defects such as conductor and ground wires,insulators,armour clamps,and so on. Diagnosis results are then arti-ficially rechecked by operation and maintenance units of lines and compared with historical defect data which may prove reli-ability of inspection results and be useful to improve operation and maintenance level of power transmission lines.%介绍了自助研发的大型无人直升机多传感器电力线路全自动巡检系统,并对该系统在广东电网部分典型运行线路上开展的规模化巡检方案及结果进行阐述.采取无人直升机通道巡检和精细巡检相结合的巡检方式,对输电线路通道环境、安全距离、异常发热、异常放电以及导地线、绝缘子、金具等线路设备外观、结构缺陷,进行多传感器、多维度同步检测和联合诊断;再将巡检诊断结果经由线路运维单位进行人工复查,并与历史缺陷数据对比,验证了巡检结果的可靠性,有助于提高输电线路运维水平.

  6. 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

  7. 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

  8. 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

  9. EDITORIAL: World Year of Physics 2005 Focus on Photoemission and Electronic Structure

    Science.gov (United States)

    2005-04-01

    , ultra-precise clocks and, at some point, maybe true nanomachines. Focus on Nano-electromechanical Systems Contents Thermomechanical noise limits on parametric sensing with nanomechanical resonators A Cleland Dynamics of a nanomechanical resonator coupled to a superconducting single-electron transistor M Blencowe, J Imbers and A Armour Simple models suffice for the single dot quantum shuttle A Donarini, T Novotny and A-P Jauho Quantum nano-electromechanics with electrons, quasiparticles and Cooper pairs: effective bath descriptions and strong feedback effects A Clerk and S Bennett Nuclear wave function interference in single-molecule electron transport M R Wegewijs and K C Nowack Self-excitation in nanoelectromechanical charge shuttles below the field emission regime F Rüting, A Erbe and C Weiss Formation of micro-tubes from strained SiGe/Si heterostructures H Qin, N Shaji, N E Merrill, H S Kim, R C Toonen, R H Blick, M M Roberts, D Savage, M G Lagally and G Celler Spin-controlled nanoelectromechanics in magnetic NEM-SET systems L Y Gorelik, D Fedorets, R I Shekhter and M Jonson Coupling between electronic transport and longitudinal phonons in suspended nanotubes S Sapmaz, P Jarillo-Herrero, Ya M Blanter and H van der Zant Phonon-assisted tunneling in interacting suspended single wall carbon nanotubes W Izumida and M Grifoni Theoretical and experimental investigations of three-terminal carbon nanotube relays S Axelsson, E E B Campbell, L M Jonsson, J M Kinaret, S W Lee, Y W Park and M Sveningsson Quantum dots in Si/SiGe 2DEGs with Schottky top-gated leads K A Slinker, K L M Lewis, C C Haselby, S Goswami, L J Klein, J O Chu, S N Coppersmith and R Joynt VHF, UHF and microwave frequency nanomechanical resonators X M H Huang, X L Feng, C A Zorman, M Mehregany and M Roukes Robert H Blick, University of Wisconsin at Madison, USA Milena Grifoni, Universität Regensburg, Germany

  10. Thermodynamic and pedogenic differences between desert microsites

    Science.gov (United States)

    Young, Michael; Caldwell, Todd; Lin, Henry

    2014-05-01

    taken along transects radiating from canopies of perennial shrubs into bare interspaces of structured soils. We augmented these measurements with ground-penetrating radar (GPR), laboratory analyses, and (in some cases) soil trenches. The results showed higher saturated conductivity under canopies versus interspaces, regardless of surface age, with the largest differences observed on older, developed soils. Bulk density, soil structure grade, and silt and clay content increased significantly away from the canopy, and organic content decreased toward interspaces. Trends in soil properties, from canopies to interspaces, were found to be predictable to a distance of 1.35 +/- 0.32 times the canopy radius, regardless of the size or genus of the shrub. The microsite environments, which are separated by only 10s of cm, release energy and mass at different rates—the fluxes differ by microsite locations. They exist with different thermodynamic gradients, with larger upward fluxes to support shrubs under canopy microsites and larger downward fluxes in interspaces. Armoured against change in interspaces can explain progressive structural evolution of pedons, a paradoxically reduced water infiltration capacity, and a contraction of canopy volumes and ecosystem production in older soils. We use these gradients to illustrate the importance of microsite location when considering complex feedbacks that result through currently-observed, time-dependent processes of pedogenesis in arid regions of the desert southwest.

  11. Calibration of a pipe hydrophone through bedload traps in a glacierized mountain basin (Saldur river, Eastern Italian Alps)

    Science.gov (United States)

    Dell'Agnese, Andrea; Huincache, Carolina; Mao, Luca; Comiti, Francesco

    2013-04-01

    The quantification of sediment transport in small mountain basins is of great relevance to assess the morphological and ecological dynamics of the entire channel network and as well as to predict flood hazards. Bedload transport in small mountain basins is highly variable in space and time due to the complexity of flow resistance sources, to the marked non-uniformity of bed sediments, to the relevance of bed armouring, as well as to varying activity and connectivity of the different sediment sources at the basin scale. In high-elevation, glaciarized basins, seasonal variability in sediment transport is known to be dramatic, but despite the relevance of such basins in many regions worldwide, very few investigations have tried to quantify it. Unfortunately, the measurement of bedload transport via direct methods is time-consuming and practically challenging at high flows. Therefore, indirect surrogate methods for bedload transport allowing its continuous measurements over time are highly desirable. Nonetheless these have to be calibrated to provide reliable estimations. This study focuses on the calibration of a pipe hydrophone in the recently established (spring 2011) monitoring station in the Saldur basin, a high-elevation glacierized watershed in the Eastern Italian Alps (18.6 km2 drainage area, about 3 km2 covered by the glacier). The hydrophone is a 0.5 m-long steel pipe closed at both ends, air-filled, with one microphone at one end, and it was developed and built in Japan. Sediment particles hitting the pipe induce an acoustic wave which is registered by the microphone. The wave is then amplified and transmitted through 6 channels, each having a different sensitivity, so that small impacts due to little particles and bigger impacts generated by coarser material are both recorded. The hydrophone was installed at about 2100 m a.s.l. within a wood log spanning the 2.9 m wide channel, where a rounded slot had been previously carved to allow half of the pipe

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. FEMALE IMAGES AS THE EKPHRASES OF ICONS IN THE PROSE OF A. PLATONOV

    Directory of Open Access Journals (Sweden)

    Elena Vasil’evna Astaschenko

    2015-11-01

    Full Text Available This article examines some of the details of the three images – a wise maiden Fevronia, who in union with Peter became the symbol of family, love and loyalty, Sofia the God’s Wisdom, Evdokia, the companion of the God’s mother on «The seeking of the Lost» icon, Mary herself. Plots reeled into the ekphrasis have always existed: in the «Iliad», in the «Oath. Viewing from the wall», Helen weaves coming battles, «bright double cover, which depicts battles, the feats of horse Trojans and Danae with copper armour, in which they suffered from Atreus’s hands», in the «Aeneid» the gates of Didon are painted both with the scenes of the Troy fall and the prophecy of the meeting with Aeneas and its fate. There is a version that all Russian literature of critical realism is an ecphrasis of icons. Platonov’s icon painting images of women, in spite their incredible artistic complexity, preserve unshakable moral folk-Christian foundation. Platonov’s prosaic Yaroslavna is a clot of the poetic power of love, accumulated by the «weeping» of a Russian woman for centuries of separation – creates high intensity in the short story «Fro» without events and conversations with her husband (not taking into account the genres of monodrama and prayer. During the revolution and ubiquitous socialist construction, Platonov wrote a story about the heroes of the railway transport, this story, however, persistently refers to the theme of abused nature, family, life, everything what the author called «the substance of existence». In 1936, the writer published this story in the journal «The literary critic» after a number of significant revisions. Platonov named this story after the protagonist – «Fro». The plot and meaning of the story is transmitted both via biographies and the pathos of the builders of a new life, who do not know yet, unlike the wise author that «not only cast faith moves people, but also a quavering doubt» and

  18. Products of steel slags an opportunity to save natural resources.

    Science.gov (United States)

    Motz, H; Geiseler, J

    2001-01-01

    In Germany, and in the most industrial countries, the use of blast furnace and steel slags as an aggregate for civil engineering, for metallurgical use and as fertiliser has a very long tradition. Since the introduction of the basic oxygen steel making furnace (BOF) process and the electric arc furnace (EAF) process the German steel industry started extensive research on the development of fields of application for BOF and EAF slags. These investigations have been mainly performed by Forschungsgemeinschaft Eisenhüttenschlacken e. V. (FEhS), the Research Association for blast furnace and steel slags. Today steel slags are well characterised and long-term experienced materials mainly used as aggregates for road construction (e.g. asphaltic or unbound layers), as armour-stones for hydraulic engineering constructions (e.g. stabilisation of shores), and as fertiliser for agriculture purposes. These multifarious fields of application could only be achieved because the steelworks influence the quality of slags by a careful selection of raw materials and a suitable process route. Furthermore, subsequent procedures like a treatment of the liquid slag, an appropriate heat treatment and a suitable processing have been developed to ensure that the quality of steel slags is always adequate for the end use. Depending on the respective field of application, the suitability of steel slags has to be proven by determining the technical properties, as well as the environmental compatibility. For this reason test methods have been developed to evaluate the technical properties especially the volume stability and the environmental behaviour. To evaluate the volume stability a suitable test (steam test) has been developed and the results from laboratory tests were compared with the behaviour of steel slags under practical conditions, e.g. in a road. To determine the environmental behaviour leaching tests have been developed. In the meanwhile most of these test methods are drafted or

  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. EDITORIAL: Focus on Mechanical Systems at the Quantum Limit FOCUS ON MECHANICAL SYSTEMS AT THE QUANTUM LIMIT

    Science.gov (United States)

    Aspelmeyer, Markus; Schwab, Keith

    2008-09-01

    Mechanical feedback in the high-frequency limit R El Boubsi, O Usmani and Ya M Blanter Back-action evasion and squeezing of a mechanical resonator using a cavity detector A A Clerk, F Marquardt and K Jacobs Simultaneous cooling and entanglement of mechanical modes of a micromirror in an optical cavity Claudiu Genes, David Vitali and Paolo Tombesi Dispersive optomechanics: a membrane inside a cavity A M Jayich, J C Sankey, B M Zwickl, C Yang, J D Thompson, S M Girvin, A A Clerk, F Marquardt and J G E Harris Cavity-assisted backaction cooling of mechanical resonators I Wilson-Rae, N Nooshi, J Dobrindt, T J Kippenberg and W Zwerger Cavity cooling of a nanomechanical resonator by light scattering I Favero and K Karrai Probing the quantum coherence of a nanomechanical resonator using a superconducting qubit: II. Implementation M P Blencowe and A D Armour Probing the quantum coherence of a nanomechanical resonator using a superconducting qubit: I. Echo scheme A D Armour and M P Blencowe Nanoelectromechanics of suspended carbon nanotubes A K Hüttel, M Poot, B Witkamp and H S J van der Zant Prospects for cooling nanomechanical motion by coupling to a superconducting microwave resonator J D Teufel, C A Regal and K W Lehnert

  1. 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

  2. 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.

  3. 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

  4. Corps-dissident, Corps-défendant. Le tatouage, une « peau de résistance »

    Directory of Open Access Journals (Sweden)

    Emma Viguier

    2010-01-01

    scripts which display and come to terms with their transgressive or even activist nature. By means of the tattoo the skin expresses itself ; it revolts, it resists. Paralysed by a situation perceived as hostile, gruelling, disgraceful or in a context of suffering, the individual uses his body as an offensive instrument of enunciation, of refusal, but also of survival. The tattoo thus asserts itself as a skin of resistance, both a weapon and an armour.Las marcas corporales como el tatuaje han sido utilizadas históricamente como una manera de estigmatizar a las personas privadas de sus derechos, marginadas de la sociedad, consideradas infames a causa de sus situaciones, religiones o actos : esclavos, detenidos, criminales, inadaptados, prostitutas, enemigos de la fe, « no-arios » en la ideología nazi. Si en las sociedades llamadas primitivas la marca inscrita en el cuerpo de un individuo acompaña los ritos de paso, en la cultura occidental ese sentido ha evolucionado y se ha convertido en una señal de barbarie, de esclavitud y de desposeimiento de toda identidad, en definitiva una señal de muerte social. Sin embargo, existen escrituras corporales que asumen y hacen alarde de sus caracteres quebrantados o incluso activistas. A través del tatuaje, la piel toma la palabra, se enfrenta, se rebela, resiste. Paralizado por una situación hostil, agotadora, indigna, en un contexto de sufrimiento, el individuo utiliza su cuerpo como un medio de supervivencia, un sistema de defensa para enunciar, para rechazar. El tatuaje se convierte de esta manera en « piel de resistencia », en arma y armadura.

  5. The new media application in elderly patients with children health literacy intervention%新媒体在老年患者子女健康素养干预中的应用

    Institute of Scientific and Technical Information of China (English)

    黄淑芬; 黄彬; 曾瑶池; 王燕

    2014-01-01

    目的:通过微信、微博等新媒体对老年患者子女健康素养进行干预,并分析评价其效果,以探索适应时代的新型健康教育模式。方法采用对照试验研究设计,将某三甲医院2012年10月~12月入住该院的老年患者随机分成新媒体干预组和对照组,利用新媒体对干预组老年患者子女进行健康素养的干预,对比干预前后的效果。结果利用新媒体对干预组老年患者的子女开展健康素养的干预,干预组干预后较干预前健康素养三个维度和五类健康问题的具备率均明显高于对照组,差异有统计学意义( P<0.01);干预后干预组健康素养三个维度和五类健康问题具备率较对照组均明显增高,差异也均有统计学意义( P<0.01);干预组中91.2%老年患者子女阅读过每一条信息,特意阅读信息者为39.2%;对信息内容34.9%的人反映很有帮助,60.2%的反映较有帮助,且77.4%认为该方式应推广。结论新媒体在老年患者子女中的应用,对提高老年健康素养具有一定的效果和优势,同时其效果要不断巩固。%Objective Through micro letter , weibo and other new media literacy intervention for elderly patients with children health, and its effect is analysis and evaluation , to explore to adapt to the era of a new mode of health education.Methods Con-trolled trial study design was used with a 3 armour hospital in October-December 2012, the institute of elderly patients randomly di-vided into intervention group and control group , the new media to take advantage of new media group of children patients'health lit-eracy intervention , the effect of contrast before and after the intervention.Results Use of new media to the intervention group of elderly patients with children health literacy intervention , intervention group after the intervention of health literacy , compared with before three dimensions and 5 kinds of health

  6. 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

  7. Editorial

    Science.gov (United States)

    2003-06-01

    In December 2002 we announced some changes to Journal of Physics B: Atomic, Molecular and Optical Physics: an extended scope to highlight the wide range of articles published in the journal and a new definition of Letters to the Editor. As always, comments and suggestions are welcome and should be sent to jphysb@iop.org. Extended scope of J. Phys. B J. Phys. B covers all aspects of atomic, molecular and optical physics. We publish articles on the study of atoms, ions, molecules, condensates or clusters, from their structure and interactions with particles, photons, fields and surfaces to all aspects of spectroscopy. Quantum optics, non-linear optics, laser physics, astrophysics, plasma physics, chemical physics, optical cooling and trapping and other investigations where the objects of study are the elementary atomic, ionic or molecular properties of processes are also included. With the introduction of the BEC Matters! portal and IOP Select, J. Phys. B, one of the major contributors, offers authors of articles in this research area wider visibility and more flexible publication with the opportunity to display multimedia attachments or web links to key groups and results. The recent papers listed below reflect the wide scope of J. Phys. B: Calculation of cross sections for very low-energy hydrogen-antihydrogen scattering using the Kohn variational method E A G Armour and C W Chamberlain J. Phys. B: At. Mol. Opt. Phys. Vol 35, No 22 (28 November 2002) L489-L494 Imaging the electron transfer reaction of Ne2+ with Ar using position-sensitive coincidence spectroscopy Sarah M Harper, Wan-Ping Hu and Stephen D Price J. Phys. B: At. Mol. Opt. Phys. Vol 35, No 21 (14 November 2002) 4409-4423 Ultraviolet-infrared wavelength scalings for strong field induced L-shell emissions from Kr and Xe clusters Alex B Borisov, Xiangyang Song, Fabrizio Frigeni, Yang Dai, Yevgeniya Koshman, W Andreas Schroeder, Jack Davis, Keith Boyer and Charles K Rhodes J. Phys. B: At. Mol. Opt. Phys

  8. 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

  9. 正规维持疗法预防消化性溃疡穿孔术后复发的疗效观察%Postoperative clinical observation of regular maintenance therapy in preventing the recurrence of peptic ulcer perforation

    Institute of Scientific and Technical Information of China (English)

    占宏静; 陈新; 古晓光; 王志涛

    2011-01-01

    Objective: To study the treatment of peptic ulcer with four drugs on gastric ulcer of perforation after merger pyloric stenosis for regular maintenance treatment, observed the clinical effects in preventing ulcer recurrence. Methods:72 patients diagnosed as gastric ulcer perforation of merger pyloric stenosis were randomly divided into two groups:treatment group with 36 patients who have done ulcer perforation excision with focal diamond, relevant pylori angioplasty drug maintenance therapy was applied after operation (armour cyanogen meters metformin or torre paclobutrazol, pull benzodiazepines). After recovery of gastrointestinal function instead of regular maintenance treatment, patients take ogilvy pull thiazole (20~400) mg/d before bedtime for six months. At the meantime, patients take DE debbi(folic acid bismuth potassium) 240 mg 2 times a day, destroy drops spirit 400 mg 2 times a day, amoxicillin 500mg 2 times a day for 4 weeks.36 patients of the control group were given postoperative drug maintenance therapy, and relevant clinical observation of the two groups was conducted. Results: 36 patients of the treatment group have fully recovered without belch, anti acid,abdominal distension, vomiting or all motality. Conventional: check with gastroscope half a year later shows the healing of ulcer, pyloric unobstructed, and no ulcer symptoms relapses was found in the follow-up period. Postoperative peristalsis recovery time of the treatment group is around 2.15 days plus or minus 0.69 days, and the length of time in hospital is around 5.89 days plus or minus 1.12 days; while that of the control group is around 3.85 days plus or minus 1.06 days and 10.02 days plus or minus 1.26 days respectively. The difference of the two groups is of statistical significance (P<0.01).Conclusion Regular maintenance therapy can effectively improve the cure rate and reduce its ulcer recurrence rate of stomach duodenal ulcer perforation merger pyloric stenosis surgery

  10. 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

  11. 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

  12. 高压交流供电挪威约阿(Gjoa)海洋钻井平台%HV AC Power Transmission to the GjØa Platfrom

    Institute of Scientific and Technical Information of China (English)

    关应涵(译)

    2013-01-01

    The oil and gas industry is constantly reviewing and judging the possibilities of new investments to explore new or upgrade existing oil and gas fields. An example of the exploration of a new oil and gas field is GjØa,which is located app.100km northwest of Bergen,Norway. The water depth in the area is 380m,and a dynamic HV cable rising from the seabed to the floating production facility was needed.The dynamic cable has to withstand the substantial mechanical stresses due to weather conditions and depth.Required fatigue properties are essential.Due to the high voltage of the power transmission,a radial water barrier was needed.No such cable has been developed or been commercially available earlier.A dynamic High Voltage XLPE cable was developed and qualified by ABB and Statoil.The cable has double armouring and a welded copper sheath as a radial water barrier and screen for the cable.Lead is normally used for this purpose but due to the extensive dynamic mechanical loading of the cable lead can not be used in this application. Without the required fatigue properties of the screen it will lose its function both as a water barrier protecting the XLPE insulation and as an electrical conducting sheath.It is the first time welded copper is used as a screen in a high voltage submarine cable.The dynamic part of the cable is about 1.5km long whereas the remaining static part maesures 99.5km This section is designed for a water depth of about 550m.The two parts were spliced in a transition joint.The cable is designed for Um=123kV.A fibre optic cable with 48 fibre elements was integrated in the cable.The fibre optic cable is used for main communication from the platform to shore, temperature monitoring close to the platform as well as regulation of the electrical system onshore.Required safety systems and functions located onshore are connected to the platform via dedicated fibres in the cable.This highly innovative project has resulted in a major step in diminishing