Sample records for ballistics

  1. Linking crime guns: the impact of ballistics imaging technology on the productivity of the Boston Police Department's Ballistics Unit.

    PubMed

    Braga, Anthony A; Pierce, Glenn L

    2004-07-01

    Ballistics imaging technology has received national attention as a potent tool for moving the law enforcement response to violent gun criminals forward by linking multiple crime scenes to one firearm. This study examines the impact of ballistics imaging technology on the productivity of the Boston Police Department's Ballistics Unit. Using negative binomial regression models to analyze times series data on ballistics matches, we find that ballistics imaging technology was associated with a more than sixfold increase in the monthly number of ballistics matches made by the Boston Police Department's Ballistics Unit. Cost-effectiveness estimates and qualitative evidence also suggest that ballistics imaging technology allows law enforcement agencies to make hits that would not have been possible using traditional ballistics methods.

  2. Ballistic Missile Intercept from UCAV

    DTIC Science & Technology

    2011-12-01

    aerodynamic forces acting on the ballistic missile , generates a ballistic flight path of the ballistic missile target based on the model developed by...for use against ballistic missile targets) [14] Hutchins, R., ME4703 “ Missile Flight Analysis ” Course Notes, Spring 2005. [15] Stevens, B., and...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release; distribution is unlimited BALLISTIC MISSILE

  3. Ballistics for the neurosurgeon.

    PubMed

    Jandial, Rahul; Reichwage, Brett; Levy, Michael; Duenas, Vincent; Sturdivan, Larry

    2008-02-01

    Craniocerebral injuries from ballistic projectiles are qualitatively different from injuries in unconfined soft tissue with similar impact. Penetrating and nonpenetrating ballistic injuries are influenced not only by the physical properties of the projectile, but also by its ballistics. Ballistics provides information on the motion of projectiles while in the gun barrel, the trajectory of the projectile in air, and the behavior of the projectile on reaching its target. This basic knowledge can be applied to better understand the ultimate craniocerebral consequences of ballistic head injuries.

  4. Ballistic projectile trajectory determining system

    DOEpatents

    Karr, Thomas J.

    1997-01-01

    A computer controlled system determines the three-dimensional trajectory of a ballistic projectile. To initialize the system, predictions of state parameters for a ballistic projectile are received at an estimator. The estimator uses the predictions of the state parameters to estimate first trajectory characteristics of the ballistic projectile. A single stationary monocular sensor then observes the actual first trajectory characteristics of the ballistic projectile. A comparator generates an error value related to the predicted state parameters by comparing the estimated first trajectory characteristics of the ballistic projectile with the observed first trajectory characteristics of the ballistic projectile. If the error value is equal to or greater than a selected limit, the predictions of the state parameters are adjusted. New estimates for the trajectory characteristics of the ballistic projectile are made and are then compared with actual observed trajectory characteristics. This process is repeated until the error value is less than the selected limit. Once the error value is less than the selected limit, a calculator calculates trajectory characteristics such a the origin and destination of the ballistic projectile.

  5. Principles of ballistics applicable to the treatment of gunshot wounds.

    PubMed

    Swan, K G; Swan, R C

    1991-04-01

    Ballistics is the science of the motion of a projectile through the barrel of a firearm (internal ballistics), during its subsequent flight (external ballistics), and during its final complicated motion after it strikes a target (terminal ballistics). Wound ballistics is a special case of terminal ballistics. Although wound ballistics is at best sets of approximations, its principles enter usefully into an evaluation of a gunshot wound and its treatment. A special consideration in these cases is their medicolegal aspects. At a minimum, the medical team receiving the patient should exert care not to destroy the clothing and in particular to cut around and not through bullet holes, to turn over to law enforcement officials any metallic foreign body recovered from the patient, and to describe precisely, or even to photograph, any entrance or exit wounds.

  6. Buildings vs. ballistics: Quantifying the vulnerability of buildings to volcanic ballistic impacts using field studies and pneumatic cannon experiments

    NASA Astrophysics Data System (ADS)

    Williams, G. T.; Kennedy, B. M.; Wilson, T. M.; Fitzgerald, R. H.; Tsunematsu, K.; Teissier, A.

    2017-09-01

    Recent casualties in volcanic eruptions due to trauma from blocks and bombs necessitate more rigorous, ballistic specific risk assessment. Quantitative assessments are limited by a lack of experimental and field data on the vulnerability of buildings to ballistic hazards. An improved, quantitative understanding of building vulnerability to ballistic impacts is required for informing appropriate life safety actions and other risk reduction strategies. We assessed ballistic impacts to buildings from eruptions at Usu Volcano and Mt. Ontake in Japan and compiled available impact data from eruptions elsewhere to identify common damage patterns from ballistic impacts to buildings. We additionally completed a series of cannon experiments which simulate ballistic block impacts to building claddings to investigate their performance over a range of ballistic projectile velocities, masses and energies. Our experiments provide new insights by quantifying (1) the hazard associated with post-impact shrapnel from building and rock fragments; (2) the effect of impact obliquity on damage; and (3) the additional impact resistance buildings possess when claddings are struck in areas directly supported by framing components. This was not well identified in previous work which may have underestimated building vulnerability to ballistic hazards. To improve assessment of building vulnerability to ballistics, we use our experimental and field data to develop quantitative vulnerability models known as fragility functions. Our fragility functions and field studies show that although unreinforced buildings are highly vulnerable to large ballistics (> 20 cm diameter), they can still provide shelter, preventing death during eruptions.

  7. 10. Storage and shipping container, ballistic missile, mounted on ballistic ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Storage and shipping container, ballistic missile, mounted on ballistic missile trailer, view from left front - Ellsworth Air Force Base, Delta Flight, 10 mile radius around Exit 127 off Interstate 90, Interior, Jackson County, SD

  8. 11. Storage and shipping container, ballistic missile, mounted on ballistic ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Storage and shipping container, ballistic missile, mounted on ballistic missile trailer, view from left side - Ellsworth Air Force Base, Delta Flight, 10 mile radius around Exit 127 off Interstate 90, Interior, Jackson County, SD

  9. Ballistic projectile trajectory determining system

    DOEpatents

    Karr, T.J.

    1997-05-20

    A computer controlled system determines the three-dimensional trajectory of a ballistic projectile. To initialize the system, predictions of state parameters for a ballistic projectile are received at an estimator. The estimator uses the predictions of the state parameters to estimate first trajectory characteristics of the ballistic projectile. A single stationary monocular sensor then observes the actual first trajectory characteristics of the ballistic projectile. A comparator generates an error value related to the predicted state parameters by comparing the estimated first trajectory characteristics of the ballistic projectile with the observed first trajectory characteristics of the ballistic projectile. If the error value is equal to or greater than a selected limit, the predictions of the state parameters are adjusted. New estimates for the trajectory characteristics of the ballistic projectile are made and are then compared with actual observed trajectory characteristics. This process is repeated until the error value is less than the selected limit. Once the error value is less than the selected limit, a calculator calculates trajectory characteristics such a the origin and destination of the ballistic projectile. 8 figs.

  10. Ballistic Testing for Interceptor Body Armor Inserts Needs Improvement

    DTIC Science & Technology

    2011-08-01

    030, “Ballistic Testing and Product Quality Surveillance for the Interceptor Body Armor - Vest Components Need Improvement,” January 3, 2011. This...Body Armor Ballistic Inserts Interceptor Body Armor (IBA) is a modular body armor system that consists of an outer tactical vest , ballistic inserts...altitude tests was because the ceramic ballistic inserts are solid structures that are not sensitive to reduced pressure and moisture. PM SEQ offered no

  11. Quantifying Ballistic Armor Performance: A Minimally Invasive Approach

    NASA Astrophysics Data System (ADS)

    Holmes, Gale; Kim, Jaehyun; Blair, William; McDonough, Walter; Snyder, Chad

    2006-03-01

    Theoretical and non-dimensional analyses suggest a critical link between the performance of ballistic resistant armor and the fundamental mechanical properties of the polymeric materials that comprise them. Therefore, a test methodology that quantifies these properties without compromising an armored vest that is exposed to the industry standard V-50 ballistic performance test is needed. Currently, there is considerable speculation about the impact that competing degradation mechanisms (e.g., mechanical, humidity, ultraviolet) may have on ballistic resistant armor. We report on the use of a new test methodology that quantifies the mechanical properties of ballistic fibers and how each proposed degradation mechanism may impact a vest's ballistic performance.

  12. An integrated approach towards future ballistic neck protection materials selection.

    PubMed

    Breeze, John; Helliker, Mark; Carr, Debra J

    2013-05-01

    Ballistic protection for the neck has historically taken the form of collars attached to the ballistic vest (removable or fixed), but other approaches, including the development of prototypes incorporating ballistic material into the collar of an under body armour shirt, are now being investigated. Current neck collars incorporate the same ballistic protective fabrics as the soft armour of the remaining vest, reflecting how ballistic protective performance alone has historically been perceived as the most important property for neck protection. However, the neck has fundamental differences from the thorax in terms of anatomical vulnerability, flexibility and equipment integration, necessitating a separate solution from the thorax in terms of optimal materials selection. An integrated approach towards the selection of the most appropriate combination of materials to be used for each of the two potential designs of future neck protection has been developed. This approach requires evaluation of the properties of each potential material in addition to ballistic performance alone, including flexibility, mass, wear resistance and thermal burden. The aim of this article is to provide readers with an overview of this integrated approach towards ballistic materials selection and an update of its current progress in the development of future ballistic neck protection.

  13. Ballistic missile defense technologies

    NASA Astrophysics Data System (ADS)

    1985-09-01

    A report on Ballistic Missile Technologies includes the following: Executive summary; Introduction; Ballistic missiles then and now; Deterrence, U.S. nuclear strategy, and BMD; BMD capabilities and the strategic balance; Crisis stability, arms race stability, and arms control issues; Ballistic missile defense technologies; Feasibility; Alternative future scenarios; Alternative R&D programs.

  14. 76 FR 14589 - Defense Federal Acquisition Regulation Supplement; Repeal of Restriction on Ballistic Missile...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-17

    ...-AH18 Defense Federal Acquisition Regulation Supplement; Repeal of Restriction on Ballistic Missile...). Section 222 repeals the restriction on purchase of Ballistic Missile Defense research, development, test... Ballistic Missile Defense research, development, test, and evaluation that was required by section 222 of...

  15. Effect of measurement on the ballistic-diffusive transition in turbid media.

    PubMed

    Glasser, Ziv; Yaroshevsky, Andre; Barak, Bavat; Granot, Er'el; Sternklar, Shmuel

    2013-10-01

    The dependence of the transition between the ballistic and the diffusive regimes of turbid media on the experimental solid angle of the detection system is analyzed theoretically and experimentally. A simple model is developed which shows the significance of experimental conditions on the location of the ballistic-diffusive transition. It is demonstrated that decreasing the solid angle expands the ballistic regime; however, this benefit is bounded by the initial Gaussian beam diffraction. In addition, choosing the appropriate wavelength according to the model's principles provides another means of expanding the ballistic regime. Consequently, by optimizing the experimental conditions, it should be possible to extract the ballistic image of a tissue with a thickness of 1 cm.

  16. Hybrid composite laminates reinforced with Kevlar/carbon/glass woven fabrics for ballistic impact testing.

    PubMed

    Randjbaran, Elias; Zahari, Rizal; Jalil, Nawal Aswan Abdul; Majid, Dayang Laila Abang Abdul

    2014-01-01

    Current study reported a facile method to investigate the effects of stacking sequence layers of hybrid composite materials on ballistic energy absorption by running the ballistic test at the high velocity ballistic impact conditions. The velocity and absorbed energy were accordingly calculated as well. The specimens were fabricated from Kevlar, carbon, and glass woven fabrics and resin and were experimentally investigated under impact conditions. All the specimens possessed equal mass, shape, and density; nevertheless, the layers were ordered in different stacking sequence. After running the ballistic test at the same conditions, the final velocities of the cylindrical AISI 4340 Steel pellet showed how much energy was absorbed by the samples. The energy absorption of each sample through the ballistic impact was calculated; accordingly, the proper ballistic impact resistance materials could be found by conducting the test. This paper can be further studied in order to characterise the material properties for the different layers.

  17. Ballistics and anatomical modelling - A review.

    PubMed

    Humphrey, Caitlin; Kumaratilake, Jaliya

    2016-11-01

    Ballistics is the study of a projectiles motion and can be broken down into four stages: internal, intermediate, external and terminal ballistics. The study of the effects a projectile has on a living tissue is referred to as wound ballistics and falls within terminal ballistics. To understand the effects a projectile has on living tissues the mechanisms of wounding need to be understood. These include the permanent and temporary cavities, energy, yawing, tumbling and fragmenting. Much ballistics research has been conducted including using cadavers, animal models and simulants such as ballistics ordnance gelatine. Further research is being conducted into developing anatomical, 3D, experimental and computational models. However, these models need to accurately represent the human body and its heterogeneous nature which involves understanding the biomechanical properties of the different tissues and organs. Further research is needed to accurately represent the human tissues with simulants and is slowly being conducted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. 48 CFR 252.225-7018 - Notice of prohibition of certain contracts with foreign entities for the conduct of ballistic...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... certain contracts with foreign entities for the conduct of ballistic missile defense research, development... foreign entities for the conduct of ballistic missile defense research, development, test, and evaluation... With Foreign Entities for the Conduct of Ballistic Missile Defense Research, Development, Test, and...

  19. Definition of an anti-missile ballistic defense architecture for Europe

    NASA Astrophysics Data System (ADS)

    Deas, M.; Tanter, A.

    1995-01-01

    The end of the Seventies and beginning of the Eighties showed significant technological developments in ballistic missiles, in particular,impact precision. These improvements caused Western strategists to be concerned with use of ballistic missiles equipped with conventional loads against military objectives (the Pact of Varsovie). The concept of ballistic missile tactical had been born. The ballistic vector, which until this time was marked with a 'strategic' label, was then 'standardized' and has interested a number of countries in the process of its development. The world has just entered the era of the ballistic proliferation. From the very start of the Eighties, the United States and, to a lesser degree, NATO lead studies and reflections concerned with defense against tactical ballistic missiles within a East West framework. From these studies the ATBM (Anti Tactical Ballistic Missile) made its appearance. In spite of the attempts at control, missile proliferation has accelerated and led, towards the end of the Eighties and the beginning of the Nineties, to the awakening of a new risk known as proliferating. The 1991 Gulf War was accelerated in this manner. This conflict also clarified the fact that the ballistic weapon constituted a formidable means of pressure for countries which had it, in spite of the PATRIOT, which demonstrated the feasibility of an active defense against ballistic missiles, in spite of their limited performances. This present presentation proposes an overall analysis of the ballistic risk and the possible threat which could result from it and examines the means available for protection against this risk by looking further into all the defensive means. This will constitute the main part of the speech. Lastly, we will endeavor to evaluate the difficulties faced by the architects of the DAMB.

  20. Wound ballistics: theory and practice.

    PubMed

    Ordog, G J; Wasserberger, J; Balasubramanium, S

    1984-12-01

    Ballistics is the study of the natural laws governing projectile missiles and their predictable performances, and wound ballistics is the study of a missile's effect on living tissue. A knowledge of these topics is essential to determine the extent and type of injury from a missile. The type of missile can often be determined by radiography. The caliber can be measured directly if the bullet is close to the x-ray plate and the x-ray tube is at least six feet from the film. Changing these distances can result in a maximum magnification of the bullet image of 20%, and the exact amount can be calculated using a formula provided. Definitions of ballistic and wound ballistic terms are provided, as are examples of wound ballistics in application.

  1. Methods for Analysis and Simulation of Ballistic Impact

    DTIC Science & Technology

    2017-04-01

    ARL-RP-0597 ● Apr 2017 US Army Research Laboratory Methods for Analysis and Simulation of Ballistic Impact by John D Clayton...Laboratory Methods for Analysis and Simulation of Ballistic Impact by John D Clayton Weapons and Materials Research Directorate, ARL...analytical, and numerical methods of ballistics research . Similar lengthy references dealing with pertinent aspects include [8, 9]. In contrast, the

  2. Hybrid Composite Laminates Reinforced with Kevlar/Carbon/Glass Woven Fabrics for Ballistic Impact Testing

    PubMed Central

    Randjbaran, Elias; Zahari, Rizal; Abdul Jalil, Nawal Aswan; Abang Abdul Majid, Dayang Laila

    2014-01-01

    Current study reported a facile method to investigate the effects of stacking sequence layers of hybrid composite materials on ballistic energy absorption by running the ballistic test at the high velocity ballistic impact conditions. The velocity and absorbed energy were accordingly calculated as well. The specimens were fabricated from Kevlar, carbon, and glass woven fabrics and resin and were experimentally investigated under impact conditions. All the specimens possessed equal mass, shape, and density; nevertheless, the layers were ordered in different stacking sequence. After running the ballistic test at the same conditions, the final velocities of the cylindrical AISI 4340 Steel pellet showed how much energy was absorbed by the samples. The energy absorption of each sample through the ballistic impact was calculated; accordingly, the proper ballistic impact resistance materials could be found by conducting the test. This paper can be further studied in order to characterise the material properties for the different layers. PMID:24955400

  3. Tunnel and field effect carrier ballistics

    NASA Technical Reports Server (NTRS)

    Kaiser, William J. (Inventor); Bell, L. Douglas (Inventor)

    1989-01-01

    Methods and apparatus for interacting carriers with a structure of matter employ an electrode for emitting said carriers at a distance from a surface of that structure, and cause such carriers to travel along ballistic trajectories inside that structure by providing along the mentioned distance a gap for performance of a process selected from the group of carrier tunneling and field emission and injecting carriers emitted by the mentioned electrode and that process ballistically into the structure through the gap and the mentioned surface. The carriers are collected or analyzed after their travel along ballistic trajectories in the structure of matter. Pertinent information on the inside of the structure is obtained by conducting inside that structure what conventionally would have been considered external ballistics, while performing the carrier-propelling internal ballistics conversely outside that structure.

  4. Thermodynamic properties of UF sub 6 measured with a ballistic piston compressor

    NASA Technical Reports Server (NTRS)

    Sterritt, D. E.; Lalos, G. T.; Schneider, R. T.

    1973-01-01

    From experiments performed with a ballistic piston compressor, certain thermodynamic properties of uranium hexafluoride were investigated. Difficulties presented by the nonideal processes encountered in ballistic compressors are discussed and a computer code BCCC (Ballistic Compressor Computer Code) is developed to analyze the experimental data. The BCCC unfolds the thermodynamic properties of uranium hexafluoride from the helium-uranium hexafluoride mixture used as the test gas in the ballistic compressor. The thermodynamic properties deduced include the specific heat at constant volume, the ratio of specific heats for UF6, and the viscous coupling constant of helium-uranium hexafluoride mixtures.

  5. The Effects of Multiple Sets of Squats and Jump Squats on Mechanical Variables.

    PubMed

    Rossetti, Michael L; Munford, Shawn N; Snyder, Brandon W; Davis, Shala E; Moir, Gavin L

    2017-07-28

    The mechanical responses to two non-ballistic squat and two ballistic jump squat protocols performed over multiple sets were investigated. One protocol from each of the two non-ballistic and ballistic conditions incorporated a pause between the eccentric and concentric phases of the movements in order to determine the influence of the coupling time on the mechanical variables and post-activation potentiation (PAP). Eleven men (age: 21.9 ± 1.8 years; height: 1.79 ± 0.05 m; mass: 87.0 ± 7.4 kg) attended four sessions where they performed multiple sets of squats and jump squats with a load equivalent to 30% 1-repeititon maximum under one of the following conditions: 1) 3 × 4 repetitions of non-ballistic squats (30N-B); 2) 3 × 4 repetitions of non-ballistic squats with a 3-second pause between the eccentric and concentric phases of each repetition (30PN-B); 3) 3 × 4 repetitions of ballistic jump squats (30B); 4) 3 × 4 repetitions of ballistic jump squats with a 3-second pause between the eccentric and concentric phases of each repetition (30PB). Force plates were used to calculate variables including average vertical velocity, average vertical force (GRF), and average power output (PO). Vertical velocities during the ballistic conditions were significantly greater than those attained during the non-ballistic conditions (mean differences: 0.21 - 0.25 m/s, p<0.001, effect sizes [ES]: 1.70 - 1.89) as were GRFs (mean differences: 478 - 526 N, p<0.001, ES: 1.61 - 1.63), and PO (mean differences: 711 - 869 W, p<0.001, ES: 1.66 - 1.73). Moreover, the increase in PO across the three sets in 30B was significantly greater than the changes observed during 30N-B, 30PN-B, and 30PB (p≤0.015). The pause reduced the mechanical variables during both the non-ballistic and ballistic conditions, although the differences were not statistically significant (p>0.05). Ballistic jump squats may be an effective exercise for developing PO given the high velocities and forces generated in these exercises. Furthermore, the completion of multiple sets of jump squats may induce PAP to enhance PO. The coupling times between the eccentric and concentric phases of the jump squats should be short in order to maximize the GRF and PO across the sets.

  6. Understanding the ballistic event : Methodology and observations relevant to ceramic armour

    NASA Astrophysics Data System (ADS)

    Healey, Adam

    The only widely-accepted method of gauging the ballistic performance of a material is to carry out ballistic testing; due to the large volume of material required for a statistically robust test, this process is very expensive. Therefore a new test, or suite of tests, that employ widely-available and economically viable characterisation methods to screen candidate armour materials is highly desirable; in order to design such a test, more information on the armour/projectile interaction is required. This work presents the design process and results of using an adapted specimen configuration to increase the amount of information obtained from a ballistic test. By using a block of ballistic gel attached to the ceramic, the fragmentation generated during the ballistic event was captured and analysed. In parallel, quasi-static tests were carried out using ring-on-ring biaxial disc testing to investigate relationships between quasi-static and ballistic fragment fracture surfaces. Three contemporary ceramic armour materials were used to design the test and to act as a baseline; Sintox FA alumina, Hexoloy SA silicon carbide and 3M boron carbide. Attempts to analyse the post-test ballistic sample non-destructively using X-ray computed tomography (XCT) were unsuccessful due to the difference in the density of the materials and the compaction of fragments. However, the results of qualitative and quantitative fracture surface analysis using scanning electron microscopy showed similarities between the fracture surfaces of ballistic fragments at the edges of the tile and biaxial fragments; this suggests a relationship between quasi-static and ballistic fragments created away from the centre of impact, although additional research will be required to determine the reason for this. Ballistic event-induced porosity was observed and quantified on the fracture surfaces of silicon carbide samples, which decreased as distance from centre of impact increased; upon further analysis this porosity was linked to the loss of a boron-rich second phase. Investigating why these inclusions are lost and the extent of the effect of this on ballistic behaviour may have important implications for the use of multi-phase ceramic materials as armour.

  7. Modeling terminal ballistics using blending-type spline surfaces

    NASA Astrophysics Data System (ADS)

    Pedersen, Aleksander; Bratlie, Jostein; Dalmo, Rune

    2014-12-01

    We explore using GERBS, a blending-type spline construction, to represent deform able thin-plates and model terminal ballistics. Strategies to construct geometry for different scenarios of terminal ballistics are proposed.

  8. On the influence of particle morphology on the post-impact ballistic response of ceramic armour materials

    NASA Astrophysics Data System (ADS)

    Hameed, Amer; Appleby-Thomas, Gareth; Wood, David; Jaansalu, Kevin

    2015-06-01

    Recent studies have shown evidence that the ballistic-resistance of fragmented (comminuted) ceramics is independent of the original strength of the material. In particular, experimental investigations into the ballistic behaviour of such fragmented ceramics have indicated that this response is correlated to shattered ceramic morphology. This suggests that careful control of ceramic microstructure - and therefore failure paths - might provide a route to optimise post-impact ballistic performance, thereby enhancing multi-hit capability. In this study, building on previous in-house work, ballistic tests were conducted using pre-formed `fragmented-ceramic' analogues based around three morphologically differing (but chemically identical) alumina feedstock materials compacted into target `pucks. In an evolution of previous work, variation of target thickness provided additional insight into an apparent morphology-based contribution to ballistic response.

  9. Temperature dependence of ballistic mobility in a metamorphic InGaAs/InAlAs high electron mobility transistor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, Jongkyong; Gang, Suhyun; Jo, Yongcheol

    We have investigated the temperature dependence of ballistic mobility in a 100 nm-long InGaAs/InAlAs metamorphic high-electron-mobility transistor designed for millimeter-wavelength RF applications. To extract the temperature dependence of quasi-ballistic mobility, our experiment involves measurements of the effective mobility in the low-bias linear region of the transistor and of the collision-dominated Hall mobility using a gated Hall bar of the same epitaxial structure. The data measured from the experiment are consistent with that of modeled ballistic mobility based on ballistic transport theory. These results advance the understanding of ballistic transport in various transistors with a nano-scale channel length that is comparable tomore » the carrier's mean free path in the channel.« less

  10. Emerging national space launch programs: Economics and safeguards

    NASA Astrophysics Data System (ADS)

    Chow, Brian G.

    Most ballistic missile nonproliferation studies have focused on trends in the numbers and performance of missiles and the resulting security threats. This report concentrates on the economic viability of emerging national space launch programs and the prospects for imposing effective safeguards against the use of space launch technology for military missiles. For the convenience of discussion in this report, a reference to ballistic missiles hereafter means surface-to-surface guided ballistic missiles only. Space launch vehicles (SLV's) are surface-to-space ballistic missiles, and they will be referred to explicitly as 'space launch vehicles' or 'space launchers'. Surface-to-surface unguided ballistic missiles will be referred to as 'rockets.'

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peterson, J.F.

    The global proliferation of ballistic missiles and weapons of mass destruction (WMD) has become one of the most immediate and dangerous threats to U.S. national security. Ballistic missiles were used in four of the last six major wars. Some 190 missiles were fired by Iraqis over a six week period at Iranian cities in 1988, during the 'War of the Cities'. Iraq's firing of Scuds against coalition forces and Israel during the Gulf War provided a vivid reminder of the threat these weapons can present to the world community. During the 1980's, many Third World countries assigned a high prioritymore » to the acquisition of ballistic missiles. By 1991, more than 20 of these nations either possessed ballistic missiles or were attempting to obtain them. Today 43 nations possess ballistic missiles. Seventeen of these probably have a nuclear weapon capability, with 20 of them possessing also a chemical or biological capability. This paper seeks to: define the military challenge ballistic missiles represent; review current U.S. counter-proliferation and nonproliferation initiatives and, finally make recommendations on other potential methods or considerations to reduce ballistic missile proliferation.« less

  12. Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues

    DTIC Science & Technology

    2012-02-13

    Ballistic Missiles Congressional Research Service Forward-Based Global Strike ( FBGS ...missiles in the CPGS program. Forward-Based Global Strike ( FBGS ) Analysts have also explored the option of deploying long-range land-based ballistic

  13. Ballistic Missile Early Warning System Clear Air Force Station, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Ballistic Missile Early Warning System - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  14. Missile Defense: Ballistic Missile Defense System Testing Delays Affect Delivery of Capabilities

    DTIC Science & Technology

    2016-04-28

    Page 1 GAO- 16 -339R Ballistic Missile Defense 441 G St. N.W. Washington, DC 20548 April 28, 2016 Congressional Committees Missile Defense...Ballistic Missile Defense System Testing Delays Affect Delivery of Capabilities For over half a century , the Department of Defense (DOD) has been...81, § 232 (a) (2011). 2 GAO- 16 -339R Ballistic Missile Defense baselines, we analyzed the testing goals for selected elements, which are

  15. Integrated Projectile Systems Synthesis Model (IPSSM)

    DTIC Science & Technology

    1976-08-01

    Lethal area effectiveness Batch mode I terior ballistics Trajectory calculations Weapon system modeling ""TRACT (Cenetsmae an revers elds It ecesuy and...Ballistics (AR) 29 E. Terminal Effectiveness Calculations (LA) 31 F. 6-D Trajectory (TR) 32 G. Recoil Mechanism Design (RM) 33 H. Sabot Design (SD) 33 I...Exterior Ballistics Program (AR) 79 Key Variable Input D2 Exterior Ballistics Program (AR) 89 List of Tables E Terminal Effectiveness Program (LA) 93

  16. Cloth Ballistic Vest Alters Response to Blast

    DTIC Science & Technology

    1988-01-01

    Detrick, Frederick, MD 21701-501 ELEMENT NO. NO. NO. jACCESSION NO. 11. TITLE (include Security Classification) CLOTH BALLSISTIC VEST ALTERS RESPONSE...Suppl. ’rintd in USA Cloth Ballistic Vest Alters Response to Blast YANCY Y. PHILLIPS, M.D., THOMAS G. MUNDIE, PH.D., JOHN T. YELVERTON, M.S., AND DONALD R...RICHMOND, PH.D. Ballistic wounds have been and will remain the principal cause of casualties in combat. Cloth ballistic vests (CBV) play an

  17. Non-Impact, Blast-Induced Mild TBI and PTSD: Concepts and Caveats

    DTIC Science & Technology

    2011-07-01

    has been verified by wound ballistics experiments in animals and finite element simulation of blast loads on the torso. Blood surge caused by...ballistic pressure waves in animals An experimental study of wound ballistics demon- strates that a ballistic pressure wave can cause a remote injury to...surge. This hypothesis has been supported by some experimental data. A volumetric surge of blood moved through the thorax and abdomen has been observed

  18. Feasibility of ballistic strengthening exercises in neurologic rehabilitation.

    PubMed

    Williams, Gavin; Clark, Ross A; Hansson, Jessica; Paterson, Kade

    2014-09-01

    Conventional methods for strength training in neurologic rehabilitation are not task specific for walking. Ballistic strength training was developed to improve the functional transfer of strength training; however, no research has investigated this in neurologic populations. The aim of this pilot study was to evaluate the feasibility of applying ballistic principles to conventional leg strengthening exercises in individuals with mobility limitations as a result of neurologic injuries. Eleven individuals with neurologic injuries completed seated and reclined leg press using conventional and ballistic techniques. A 2 × 2 repeated-measures analysis of variance was used to compare power measures (peak movement height and peak velocity) between exercises and conditions. Peak jump velocity and peak jump height were greater when using the ballistic jump technique rather than the conventional concentric technique (P < 0.01). These findings suggest that when compared with conventional strengthening exercises, the incorporation of ballistic principles was associated with increased peak height and peak velocities.

  19. Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues

    DTIC Science & Technology

    2013-01-10

    and Long-Range Ballistic Missiles Congressional Research Service Forward-Based Global Strike ( FBGS ...they may address the nuclear ambiguity issues raised by long-range ballistic missiles in the CPGS program. Forward-Based Global Strike ( FBGS

  20. The Effects of Ballistic and Non-Ballistic Bench Press on Mechanical Variables.

    PubMed

    Moir, Gavin L; Munford, Shawn N; Moroski, Lindsey L; Davis, Shala E

    2017-02-21

    To investigate the effects of ballistic and non-ballistic bench press performed with loads equivalent to 30 and 90% 1-repetition maximum (1-RM) on mechanical variables. Eleven resistance-trained men (age: 23.0 ± 1.4 years; mass: 98.4 ± 14.4 kg) attended four testing sessions where they performed one of the following sessions: 1) three sets of five non-ballistic repetitions performed with a load equivalent to 30% 1-RM (30N-B), 2) three sets of five ballistic repetitions performed with a load equivalent to 30% 1-RM (30B), 3) three sets of four non-ballistic repetitions with a load equivalent to 90% 1-RM (90N-B), 4) three sets of four ballistic repetitions with a load equivalent to 90% 1-RM (90B). Force plates and a 3-D motion analysis system were used to determine the velocity, force, power output (PO) and work during each repetition. The heavier loads resulted in significantly greater forces applied to the barbell (mean differences: 472-783 N, p<0.001), but lower barbell velocities (mean differences: 0.85-1.20 m/s, p<0.001) and PO (mean differences: 118-492 W, p≤0.022). The ballistic conditions enhanced the mechanical variables only at the lower load with 30B producing significantly greater force (mean difference: 263 N, p<0.001), velocity (mean difference: 0.33 m/s, p<0.001), and PO (mean difference: 335 W, p<0.001) compared to 30N-B. Furthermore, the increase in PO across the 3 sets in 30B was significantly different from all other conditions (p=0.013). The total mechanical work performed was significantly greater for the conditions with the heavier loads compared to those with the lighter loads (mean differences: 3,62-5,600 J, p<0.001) and that performed during the ballistic conditions was significantly greater than that performed during the non-ballistic conditions with the same load (mean differences: 945-1,030 J, p<0.001). Ballistic bench press may be an effective exercise for developing power output and multiple sets may elicit post-activation potentiation that enhances force production. However, these benefits may be negated at heavier loads.

  1. Sagnac effect and Ritz ballistic hypothesis (Review)

    NASA Astrophysics Data System (ADS)

    Malykin, G. B.

    2010-12-01

    It is shown that the Ritz ballistic hypothesis, which is based on the vector summation of the speed of light with the velocity of the radiation source, contradicts the fact of existence of the Sagnac effect. Based on a particular example of a three-mirror ring interferometer, it is shown that the application of the Ritz ballistic hypothesis leads to an obvious calculation error, namely, to the appearance of a difference in the propagation times of counterpropagating waves in the absence of rotation. A review is given of experiments and of results of processing of astronomical observations and discussions devoted to testing the Ritz ballistic hypothesis. A number of other physical phenomena that refute the Ritz ballistic hypothesis are considered.

  2. Assessment and monitoring of ballistic and maximal upper-body strength qualities in athletes.

    PubMed

    Young, Kieran P; Haff, G Gregory; Newton, Robert U; Gabbett, Tim J; Sheppard, Jeremy M

    2015-03-01

    To evaluate whether the dynamic strength index (DSI: ballistic peak force/isometric peak force) could be effectively used to guide specific training interventions and detect training-induced changes in maximal and ballistic strength. Twenty-four elite male athletes were assessed in the isometric bench press and a 45% 1-repetition-maximum (1RM) ballistic bench throw using a force plate and linear position transducer. The DSI was calculated using the peak force values obtained during the ballistic bench throw and isometric bench press. Athletes were then allocated into 2 groups as matched pairs based on their DSI and strength in the 1RM bench press. Over the 5 wk of training, athletes performed either high-load (80-100% 1RM) bench press or moderate-load (40-55% 1RM) ballistic bench throws. The DSI was sensitive to disparate training methods, with the bench-press group increasing isometric bench-press peak force (P=.035, 91% likely), and the ballistic-bench-throw group increasing bench-throw peak force to a greater extent (P≤.001, 83% likely). A significant increase (P≤.001, 93% likely) in the DSI was observed for both groups. The DSI can be used to guide specific training interventions and can detect training-induced changes in isometric bench-press and ballistic bench-throw peak force over periods as short as 5 wk.

  3. Room-temperature ballistic transport in III-nitride heterostructures.

    PubMed

    Matioli, Elison; Palacios, Tomás

    2015-02-11

    Room-temperature (RT) ballistic transport of electrons is experimentally observed and theoretically investigated in III-nitrides. This has been largely investigated at low temperatures in low band gap III-V materials due to their high electron mobilities. However, their application to RT ballistic devices is limited by their low optical phonon energies, close to KT at 300 K. In addition, the short electron mean-free-path at RT requires nanoscale devices for which surface effects are a limitation in these materials. We explore the unique properties of wide band-gap III-nitride semiconductors to demonstrate RT ballistic devices. A theoretical model is proposed to corroborate experimentally their optical phonon energy of 92 meV, which is ∼4× larger than in other III-V semiconductors. This allows RT ballistic devices operating at larger voltages and currents. An additional model is described to determine experimentally a characteristic dimension for ballistic transport of 188 nm. Another remarkable property is their short carrier depletion at device sidewalls, down to 13 nm, which allows top-down nanofabrication of very narrow ballistic devices. These results open a wealth of new systems and basic transport studies possible at RT.

  4. Ballistic Deficits for Ionization Chamber Pulses in Pulse Shaping Amplifiers

    NASA Astrophysics Data System (ADS)

    Kumar, G. Anil; Sharma, S. L.; Choudhury, R. K.

    2007-04-01

    In order to understand the dependence of the ballistic deficit on the shape of rising portion of the voltage pulse at the input of a pulse shaping amplifier, we have estimated the ballistic deficits for the pulses from a two-electrode parallel plate ionization chamber as well as for the pulses from a gridded parallel plate ionization chamber. These estimations have been made using numerical integration method when the pulses are processed through the CR-RCn (n=1-6) shaping network as well as when the pulses are processed through the complex shaping network of the ORTEC Model 472 spectroscopic amplifier. Further, we have made simulations to see the effect of ballistic deficit on the pulse-height spectra under different conditions. We have also carried out measurements of the ballistic deficits for the pulses from a two-electrode parallel plate ionization chamber as well as for the pulses from a gridded parallel plate ionization chamber when these pulses are processed through the ORTEC 572 linear amplifier having a simple CR-RC shaping network. The reasonable matching of the simulated ballistic deficits with the experimental ballistic deficits for the CR-RC shaping network clearly establishes the validity of the simulation technique

  5. Aerothermodynamic Testing of Aerocapture and Planetary Probe Geometries in Hypersonic Ballistic-Range Environments

    NASA Technical Reports Server (NTRS)

    Wilder, M. C.; Reda, D. C.; Bogdanoff, D. W.; Olejniczak, J.

    2005-01-01

    A viewgraph presentation on aerothermodynamic testing of aerocapture and planetary probe design methods in hypersonic ballistic range environments is shown. The topics include: 1) Ballistic Range Testing; 2) NASA-Ames Hypervelocity Free Flight Facility; and 3) Representative Results.

  6. Ballistic transport in graphene grown by chemical vapor deposition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Calado, V. E.; Goswami, S.; Xu, Q.

    2014-01-13

    In this letter, we report the observation of ballistic transport on micron length scales in graphene synthesised by chemical vapour deposition (CVD). Transport measurements were done on Hall bar geometries in a liquid He cryostat. Using non-local measurements, we show that electrons can be ballistically directed by a magnetic field (transverse magnetic focussing) over length scales of ∼1 μm. Comparison with atomic force microscope measurements suggests a correlation between the absence of wrinkles and the presence of ballistic transport in CVD graphene.

  7. Quantum transport in d-dimensional lattices

    DOE PAGES

    Manzano, Daniel; Chuang, Chern; Cao, Jianshu

    2016-04-28

    We show that both fermionic and bosonic uniform d-dimensional lattices can be reduced to a set of independent one-dimensional chains. This reduction leads to the expression for ballistic energy fluxes in uniform fermionic and bosonic lattices. By the use of the Jordan–Wigner transformation we can extend our analysis to spin lattices, proving the coexistence of both ballistic and non-ballistic subspaces in any dimension and for any system size. Lastly, we then relate the nature of transport to the number of excitations in the homogeneous spin lattice, indicating that a single excitation always propagates ballistically and that the non-ballistic behaviour ofmore » uniform spin lattices is a consequence of the interaction between different excitations.« less

  8. Ballistic phonon transport in holey silicon.

    PubMed

    Lee, Jaeho; Lim, Jongwoo; Yang, Peidong

    2015-05-13

    When the size of semiconductors is smaller than the phonon mean free path, phonons can carry heat with no internal scattering. Ballistic phonon transport has received attention for both theoretical and practical aspects because Fourier's law of heat conduction breaks down and the heat dissipation in nanoscale transistors becomes unpredictable in the ballistic regime. While recent experiments demonstrate room-temperature evidence of ballistic phonon transport in various nanomaterials, the thermal conductivity data for silicon in the length scale of 10-100 nm is still not available due to experimental challenges. Here we show ballistic phonon transport prevails in the cross-plane direction of holey silicon from 35 to 200 nm. The thermal conductivity scales linearly with the length (thickness) even though the lateral dimension (neck) is as narrow as 20 nm. We assess the impact of long-wavelength phonons and predict a transition from ballistic to diffusive regime using scaling models. Our results support strong persistence of long-wavelength phonons in nanostructures and are useful for controlling phonon transport for thermoelectrics and potential phononic applications.

  9. A Residual Mass Ballistic Testing Method to Compare Armor Materials or Components (Residual Mass Ballistic Testing Method)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Benjamin Langhorst; Thomas M Lillo; Henry S Chu

    2014-05-01

    A statistics based ballistic test method is presented for use when comparing multiple groups of test articles of unknown relative ballistic perforation resistance. The method is intended to be more efficient than many traditional methods for research and development testing. To establish the validity of the method, it is employed in this study to compare test groups of known relative ballistic performance. Multiple groups of test articles were perforated using consistent projectiles and impact conditions. Test groups were made of rolled homogeneous armor (RHA) plates and differed in thickness. After perforation, each residual projectile was captured behind the target andmore » its mass was measured. The residual masses measured for each test group were analyzed to provide ballistic performance rankings with associated confidence levels. When compared to traditional V50 methods, the residual mass (RM) method was found to require fewer test events and be more tolerant of variations in impact conditions.« less

  10. Room-temperature ballistic energy transport in molecules with repeating units

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rubtsova, Natalia I.; Nyby, Clara M.; Zhang, Hong

    2015-06-07

    In materials, energy can propagate by means of two limiting regimes: diffusive and ballistic. Ballistic energy transport can be fast and efficient and often occurs with a constant speed. Using two-dimensional infrared spectroscopy methods, we discovered ballistic energy transport via individual polyethylene chains with a remarkably high speed of 1440 m/s and the mean free path length of 14.6 Å in solution at room temperature. Whereas the transport via the chains occurs ballistically, the mechanism switches to diffusive with the effective transport speed of 130 m/s at the end-groups attached to the chains. A unifying model of the transport inmore » molecules is presented with clear time separation and additivity among the transport along oligomeric fragments, which occurs ballistically, and the transport within the disordered fragments, occurring diffusively. The results open new avenues for making novel elements for molecular electronics, including ultrafast energy transporters, controlled chemical reactors, and sub-wavelength quantum nanoseparators.« less

  11. 48 CFR 225.7016 - Restriction on Ballistic Missile Defense research, development, test, and evaluation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Restriction on Ballistic Missile Defense research, development, test, and evaluation. 225.7016 Section 225.7016 Federal Acquisition... Acquisition 225.7016 Restriction on Ballistic Missile Defense research, development, test, and evaluation. [68...

  12. A ballistic mission to fly by Comet Halley

    NASA Technical Reports Server (NTRS)

    Boain, R. J.; Hastrup, R. C.

    1980-01-01

    The paper describes the available options, ballistic trajectory opportunities, and a preliminary reference trajectory that were selected as a basis for spacecraft design studies and programmatic planning for a Halley ballistic intercept mission in 1986. The paper also presents trajectory, performance, and navigation data which support the preliminary selection.

  13. Ballistic Resistance of Armored Passenger Vehicles: Test Protocols and Quality Methods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeffrey M. Lacy; Robert E. Polk

    2005-07-01

    This guide establishes a test methodology for determining the overall ballistic resistance of the passenger compartment of assembled nontactical armored passenger vehicles (APVs). Because ballistic testing of every piece of every component of an armored vehicle is impractical, if not impossible, this guide describes a testing scheme based on statistical sampling of exposed component surface areas. Results from the test of the sampled points are combined to form a test score that reflects the probability of ballistic penetration into the passenger compartment of the vehicle.

  14. Preservation and storage of prepared ballistic gelatine.

    PubMed

    Mattijssen, E J A T; Alberink, I; Jacobs, B; van den Boogaard, Y

    2016-02-01

    The use of ballistic gelatine, generally accepted as a human muscle tissue simulant in wound ballistic studies, might be improved by adding a preservative (Methyl 4-hydroxybenzoate) which inhibits microbial growth. This study shows that replacing a part of the gelatine powder by the preservative does not significantly alter the penetration depth of projectiles. Storing prepared blocks of ballistic gelatine over time decreased the penetration depth of projectiles. Storage of prepared gelatine for 4 week already showed a significant effect on the penetration depth of projectiles. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Sensor Fusion of Gaussian Mixtures for Ballistic Target Tracking in the Re-Entry Phase

    PubMed Central

    Lu, Kelin; Zhou, Rui

    2016-01-01

    A sensor fusion methodology for the Gaussian mixtures model is proposed for ballistic target tracking with unknown ballistic coefficients. To improve the estimation accuracy, a track-to-track fusion architecture is proposed to fuse tracks provided by the local interacting multiple model filters. During the fusion process, the duplicate information is removed by considering the first order redundant information between the local tracks. With extensive simulations, we show that the proposed algorithm improves the tracking accuracy in ballistic target tracking in the re-entry phase applications. PMID:27537883

  16. Ballistic Transport Exceeding 28 μm in CVD Grown Graphene.

    PubMed

    Banszerus, Luca; Schmitz, Michael; Engels, Stephan; Goldsche, Matthias; Watanabe, Kenji; Taniguchi, Takashi; Beschoten, Bernd; Stampfer, Christoph

    2016-02-10

    We report on ballistic transport over more than 28 μm in graphene grown by chemical vapor deposition (CVD) that is fully encapsulated in hexagonal boron nitride. The structures are fabricated by an advanced dry van-der-Waals transfer method and exhibit carrier mobilities of up to three million cm(2)/(Vs). The ballistic nature of charge transport is probed by measuring the bend resistance in cross- and square-shaped devices. Temperature-dependent measurements furthermore prove that ballistic transport is maintained exceeding 1 μm up to 200 K.

  17. Sensor Fusion of Gaussian Mixtures for Ballistic Target Tracking in the Re-Entry Phase.

    PubMed

    Lu, Kelin; Zhou, Rui

    2016-08-15

    A sensor fusion methodology for the Gaussian mixtures model is proposed for ballistic target tracking with unknown ballistic coefficients. To improve the estimation accuracy, a track-to-track fusion architecture is proposed to fuse tracks provided by the local interacting multiple model filters. During the fusion process, the duplicate information is removed by considering the first order redundant information between the local tracks. With extensive simulations, we show that the proposed algorithm improves the tracking accuracy in ballistic target tracking in the re-entry phase applications.

  18. Radar signal analysis of ballistic missile with micro-motion based on time-frequency distribution

    NASA Astrophysics Data System (ADS)

    Wang, Jianming; Liu, Lihua; Yu, Hua

    2015-12-01

    The micro-motion of ballistic missile targets induces micro-Doppler modulation on the radar return signal, which is a unique feature for the warhead discrimination during flight. In order to extract the micro-Doppler feature of ballistic missile targets, time-frequency analysis is employed to process the micro-Doppler modulated time-varying radar signal. The images of time-frequency distribution (TFD) reveal the micro-Doppler modulation characteristic very well. However, there are many existing time-frequency analysis methods to generate the time-frequency distribution images, including the short-time Fourier transform (STFT), Wigner distribution (WD) and Cohen class distribution, etc. Under the background of ballistic missile defence, the paper aims at working out an effective time-frequency analysis method for ballistic missile warhead discrimination from the decoys.

  19. Localization of small arms fire using acoustic measurements of muzzle blast and/or ballistic shock wave arrivals.

    PubMed

    Lo, Kam W; Ferguson, Brian G

    2012-11-01

    The accurate localization of small arms fire using fixed acoustic sensors is considered. First, the conventional wavefront-curvature passive ranging method, which requires only differential time-of-arrival (DTOA) measurements of the muzzle blast wave to estimate the source position, is modified to account for sensor positions that are not strictly collinear (bowed array). Second, an existing single-sensor-node ballistic model-based localization method, which requires both DTOA and differential angle-of-arrival (DAOA) measurements of the muzzle blast wave and ballistic shock wave, is improved by replacing the basic external ballistics model (which describes the bullet's deceleration along its trajectory) with a more rigorous model and replacing the look-up table ranging procedure with a nonlinear (or polynomial) equation-based ranging procedure. Third, a new multiple-sensor-node ballistic model-based localization method, which requires only DTOA measurements of the ballistic shock wave to localize the point of fire, is formulated. The first method is applicable to situations when only the muzzle blast wave is received, whereas the third method applies when only the ballistic shock wave is received. The effectiveness of each of these methods is verified using an extensive set of real data recorded during a 7 day field experiment.

  20. Civilian casualties of Iranian cities by ballistic missile attacks during the Iraq-Iran war (1980-1988).

    PubMed

    Khaji, Ali; Fallahdoost, Shoaodin; Soroush, Mohammad Reza

    2010-04-01

    To determine the nature and extent of Iranian casualties by ballistic missile attacks during the eight years of the Iraq-Iran war. The data collected about Iraqi missile strikes on Iranian cities included the following: date and time, number and type of missiles, cities targeted, and injuries and deaths resulting from impacts of missiles in civilian areas. The data were extracted from a database that was constructed by the army staff headquarters based on daily reports of Iranian army units during the war. Over a period of eight years (1980-1988), Iraqi army fired 533 ballistic missiles at Iranian territories. From those, 414 missiles (77.7%) landed on Iranian cities. The impacts of these missiles caused the deaths of 2,312 civilians and injured 11,625 others. Three types of ballistic missiles were used: FROG-7, Scud, and Al-Hussein (a modified version of the Scud missile). Twenty-seven cities in Iran were struck by Iraqi ballistic missiles. The highest mortalities from ballistic missiles were in Dezful and Tehran. Iraqi missile attacks continued for 90 months (2,748 days). Our results point to the necessity of investigating the psychological consequences of Iraqi ballistic missile attacks among survivors in 27 Iranian cities during the eight years of the Iraq-Iran war.

  1. Analysis of spacecraft entry into Mars atmosphere

    NASA Astrophysics Data System (ADS)

    Nakajima, Ken; Nagano, Koutarou

    1991-07-01

    The effects on a spacecraft body while entering the Martian atmosphere and the resulting design constraints are analyzed. The analyses are conducted using the Viking entry phase restriction conditions and a Mars atmosphere model. Results from analysis conducted by the Program to Optimize Simulated Trajectories (POST) are described. Results obtained from the analysis are as follows: (1) flight times depend greatly on lift-to-drag ratio and less on ballistic coefficients; (2) terminal landing speeds depend greatly on ballistic coefficients and less on lift-to-drag ratios; (3) the dependence of the flight path angles on ballistic coefficients is slightly larger than their dependence on lift-to-drag ratios; (4) as the ballistic coefficients become smaller and the lift-to-drag ratios become larger, the deceleration at high altitude becomes larger; (5) small ballistic coefficients and low lift-to-drag ratios are required to meet the constraints of Mach number at parachute deployment and deployment altitude; and (6) heating rates at stagnation points are dependent on ballistic coefficients. It is presumed that the aerodynamic characteristics will be 0.2 for the lift-to-drag ratio and 75 kg/sq m for the ballistic coefficient for the case of a Mars landing using capsules similar to those used in the Viking program.

  2. 3-D ballistic transport of ellipsoidal volcanic projectiles considering horizontal wind field and variable shape-dependent drag coefficients

    NASA Astrophysics Data System (ADS)

    Bertin, Daniel

    2017-02-01

    An innovative 3-D numerical model for the dynamics of volcanic ballistic projectiles is presented here. The model focuses on ellipsoidal particles and improves previous approaches by considering horizontal wind field, virtual mass forces, and drag forces subjected to variable shape-dependent drag coefficients. Modeling suggests that the projectile's launch velocity and ejection angle are first-order parameters influencing ballistic trajectories. The projectile's density and minor radius are second-order factors, whereas both intermediate and major radii of the projectile are of third order. Comparing output parameters, assuming different input data, highlights the importance of considering a horizontal wind field and variable shape-dependent drag coefficients in ballistic modeling, which suggests that they should be included in every ballistic model. On the other hand, virtual mass forces should be discarded since they almost do not contribute to ballistic trajectories. Simulation results were used to constrain some crucial input parameters (launch velocity, ejection angle, wind speed, and wind azimuth) of the block that formed the biggest and most distal ballistic impact crater during the 1984-1993 eruptive cycle of Lascar volcano, Northern Chile. Subsequently, up to 106 simulations were performed, whereas nine ejection parameters were defined by a Latin-hypercube sampling approach. Simulation results were summarized as a quantitative probabilistic hazard map for ballistic projectiles. Transects were also done in order to depict aerial hazard zones based on the same probabilistic procedure. Both maps combined can be used as a hazard prevention tool for ground and aerial transits nearby unresting volcanoes.

  3. 3D topography measurements on correlation cells—a new approach to forensic ballistics identifications

    NASA Astrophysics Data System (ADS)

    Song, John; Chu, Wei; Tong, Mingsi; Soons, Johannes

    2014-06-01

    Based on three-dimensional (3D) topography measurements on correlation cells, the National Institute of Standards and Technology (NIST) has developed the ‘NIST Ballistics Identification System (NBIS)’ aimed at accurate ballistics identifications and fast ballistics evidence searches. The 3D topographies are divided into arrays of correlation cells to identify ‘valid correlation areas’ and eliminate ‘invalid correlation areas’ from the matching and identification procedure. A ‘congruent matching cells’ (CMC)’ method using three types of identification parameters of the paired correlation cells (cross correlation function maximum CCFmax, spatial registration position in x-y and registration angle θ) is used for high accuracy ballistics identifications. ‘Synchronous processing’ is proposed for correlating multiple cell pairs at the same time to increase the correlation speed. The proposed NBIS can be used for correlations of both geometrical topographies and optical intensity images. All the correlation parameters and algorithms are in the public domain and subject to open tests. An error rate reporting procedure has been developed that can greatly add to the scientific support for the firearm and toolmark identification specialty, and give confidence to the trier of fact in court proceedings. The NBIS is engineered to employ transparent identification parameters and criteria, statistical models and correlation algorithms. In this way, interoperability between different ballistics identification systems can be more easily achieved. This interoperability will make the NBIS suitable for ballistics identifications and evidence searches with large national databases, such as the National Integrated Ballistic Information Network in the United States.

  4. 75 FR 64714 - Meeting of the Chief of Naval Operations Executive Panel

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

    ... recommendations of the Subcommittee on Navy's Role in Ballistic Missile Defense. The meeting will consist of discussions of Navy's role in ballistic missile defense, development of the global missile defense network and evolution of the growing ballistic missile threat. DATES: The meeting will be held on November 12, 2010...

  5. Whither Ballistic Missile Defense?

    DTIC Science & Technology

    1992-11-30

    Conference on Technical Marketing 2000: Opportunities and Strategies for a Changing World) I intend to discuss the prospects for SDI in a changing...Technical Marketing 2000: Opportunities and Strategies for a Changing World) Descriptors, Keywords: Cooper Speech Ballistic Missile Defense...WHITHER BALLISTIC MISSILE DEFENSE? BY AMBASSADOR HENRY F. COOPER NOVEMBER 30,1992 TECHNICAL MARKETING SOCIETY OF AMERICA WASHINGTON, DC

  6. Optimization of Aimpoints for Coordinate Seeking Weapons

    DTIC Science & Technology

    2015-09-01

    aiming) and independent ( ballistic ) errors are taken into account, before utilizing each of the three damage functions representing the weapon. A Monte...characteristics such as the radius of the circle containing the weapon aimpoint, impact angle, dependent (aiming) and independent ( ballistic ) errors are taken...Dependent (Aiming) Error .................................8 2. Single Weapon Independent ( Ballistic ) Error .............................9 3

  7. Management of civilian ballistic fractures.

    PubMed

    Seng, V S; Masquelet, A C

    2013-12-01

    The management of ballistic fractures, which are open fractures, has often been studied in wartime and has benefited from the principles of military surgery with debridement and lavage, and the use of external fixation for bone stabilization. In civilian practice, bone stabilization of these fractures is different and is not performed by external fixation. Fifteen civilian ballistic fractures, Gustilo II or IIIa, two associated with nerve damage and none with vascular damage, were reviewed. After debridement and lavage, ten internal fixations and five conservative treatments were used. No superficial or deep surgical site infection was noted. Fourteen of the 15 fractures (93%) healed without reoperation. Eleven of the 15 patients (73%) regained normal function. Ballistic fractures have a bad reputation due to their many complications, including infections. In civilian practice, the use of internal fixation is not responsible for excessive morbidity, provided debridement and lavage are performed. Civilian ballistic fractures, when they are caused by low-velocity firearms, differ from military ballistic fractures. Although the principle of surgical debridement and lavage remains the same, bone stabilization is different and is similar to conventional open fractures. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Multiple pole electromagnetic propulsion system with separated ballistic guidance and electrical current contact surfaces

    DOEpatents

    Sims, Jr., James R.

    2008-07-15

    An electromagnetic propulsion system is disclosed having separate rails for ballistic guidance and for carrying current. In this system, one or more pairs of ballistic guidance rails are provided, with each ballistic guidance rail having a pair of current carrying rails joined to it to form a combined rail. Each combined rail is separated electrically from adjacent combined rails by electrically insulating blocks. Each of the current carrying rails in a given combined rail pair have the same electrical polarity, and the polarities alternate between adjacent combined rails. Armatures contact current carrying rails to complete the circuit to generate the accelerating Lorentz force on the armatures. Bore riders on the sabot and/or projectile are in contact with the ballistic guide rails. Separation of the current carrying and ballistic guidance functions increases resistance of the system to rail movement and bending, as well as reduced wear/damage to the rails. In further embodiments, a circumferential over wrap providing compressive force on the rails further increases resistance of the system to rail movement and bending.

  9. A simple Boltzmann transport equation for ballistic to diffusive transient heat transport

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maassen, Jesse, E-mail: jmaassen@purdue.edu; Lundstrom, Mark

    2015-04-07

    Developing simplified, but accurate, theoretical approaches to treat heat transport on all length and time scales is needed to further enable scientific insight and technology innovation. Using a simplified form of the Boltzmann transport equation (BTE), originally developed for electron transport, we demonstrate how ballistic phonon effects and finite-velocity propagation are easily and naturally captured. We show how this approach compares well to the phonon BTE, and readily handles a full phonon dispersion and energy-dependent mean-free-path. This study of transient heat transport shows (i) how fundamental temperature jumps at the contacts depend simply on the ballistic thermal resistance, (ii) thatmore » phonon transport at early times approach the ballistic limit in samples of any length, and (iii) perceived reductions in heat conduction, when ballistic effects are present, originate from reductions in temperature gradient. Importantly, this framework can be recast exactly as the Cattaneo and hyperbolic heat equations, and we discuss how the key to capturing ballistic heat effects is to use the correct physical boundary conditions.« less

  10. Bringing in the Reinforcements

    NASA Technical Reports Server (NTRS)

    2004-01-01

    What do NASA and ballistics have in common? More than the average person may know. Everyday, millions of Americans drive in vehicles, cross over bridges, and fly in airplanes without knowing just how important NASA s role in studying ballistics is in making these actions viable and safe for them. At Glenn Research Center s Ballistic Impact Facility, NASA scientists and engineers study the dynamics of high-speed projectiles and their impact on targets to create materials and structures that are smarter, lighter, and stronger. By applying the science of ballistics to new developments, these researchers are taking major steps in preventing catastrophic events. The Ballistic Impact Facility s main features are a 40-foot-long gas gun that can launch projectiles at speeds over 1,000 miles per hour and highspeed cameras that can capture up to 250 million images per second.

  11. A research study for the preliminary definition of an aerophysics free-flight laboratory facility

    NASA Technical Reports Server (NTRS)

    Canning, Thomas N.

    1988-01-01

    A renewed interest in hypervelocity vehicles requires an increase in the knowledge of aerodynamic phenomena. Tests conducted with ground-based facilities can be used both to better understand the physics of hypervelocity flight, and to calibrate and validate computer codes designed to predict vehicle performance in the hypervelocity environment. This research reviews the requirements for aerothermodynamic testing and discusses the ballistic range and its capabilities. Examples of the kinds of testing performed in typical high performance ballistic ranges are described. We draw heavily on experience obtained in the ballistics facilities at NASA Ames Research Center, Moffett Field, California. Prospects for improving the capabilities of the ballistic range by using advanced instrumentation are discussed. Finally, recent developments in gun technology and their application to extend the capability of the ballistic range are summarized.

  12. Natural Mallow Fiber-Reinforced Epoxy Composite for Ballistic Armor Against Class III-A Ammunition

    NASA Astrophysics Data System (ADS)

    Nascimento, Lucio Fabio Cassiano; Holanda, Luane Isquerdo Ferreira; Louro, Luis Henrique Leme; Monteiro, Sergio Neves; Gomes, Alaelson Vieira; Lima, Édio Pereira

    2017-10-01

    Epoxy matrix composites reinforced with up to 30 vol pct of continuous and aligned natural mallow fibers were for the first time ballistic tested as personal armor against class III-A 9 mm FMJ ammunition. The ballistic efficiency of these composites was assessed by measuring the dissipated energy and residual velocity after the bullet perforation. The results were compared to those in similar tests of aramid fabric (Kevlar™) commonly used in vests for personal protections. Visual inspection and scanning electron microscopy analysis of impact-fractured samples revealed failure mechanisms associated with fiber pullout and rupture as well as epoxy cracking. As compared to Kevlar™, the mallow fiber composite displayed practically the same ballistic efficiency. However, there is a reduction in both weight and cost, which makes the mallow fiber composites a promising material for personal ballistic protection.

  13. Fake ballistics and real explosions: field-scale experiments on the ejection and emplacement of volcanic bombs during vent-clearing explosive activity

    NASA Astrophysics Data System (ADS)

    Taddeucci, J.; Valentine, G.; Gaudin, D.; Graettinger, A. H.; Lube, G.; Kueppers, U.; Sonder, I.; White, J. D.; Ross, P.; Bowman, D. C.

    2013-12-01

    Ballistics - bomb-sized pyroclasts that travel from volcanic source to final emplacement position along ballistic trajectories - represent a prime source of volcanic hazard, but their emplacement range, size, and density is useful to inverse model key eruption parameters related to their initial ejection velocity. Models and theory, however, have so far focused on the trajectory of ballistics after leaving the vent, neglecting the complex dynamics of their initial acceleration phase in the vent/conduit. Here, we use field-scale buried explosion experiments to study the ground-to-ground ballistic emplacement of particles through their entire acceleration-deceleration cycle. Twelve blasts were performed at the University at Buffalo Large Scale Experimental Facility with a range of scaled depths (burial depth divided by the cubic root of the energy of the explosive charge) and crater configurations. In all runs, ballistic analogs were placed on the ground surface at variable distance from the vertical projection of the buried charge, resulting in variable ejection angle. The chosen analogs are tennis and ping-pong balls filled with different materials, covering a limited range of sizes and densities. The analogs are tracked in multiple high-speed and high-definition videos, while Particle Image Velocimetry is used to detail ground motion in response to the buried blasts. In addition, after each blast the emplacement position of all analog ballistics was mapped with respect to the blast location. Preliminary results show the acceleration history of ballistics to be quite variable, from very short and relatively simple acceleration coupled with ground motion, to more complex, multi-stage accelerations possibly affected not only by the initial ground motion but also by variable coupling with the gas-particle mixture generated by the blasts. Further analysis of the experimental results is expected to provide new interpretative tools for ballistic deposits and better hazard assessment, with particular emphasis for the case of vent-opening eruptions driven by explosive gas expansion beneath loose debris.

  14. A Novel Binarization Algorithm for Ballistics Firearm Identification

    NASA Astrophysics Data System (ADS)

    Li, Dongguang

    The identification of ballistics specimens from imaging systems is of paramount importance in criminal investigation. Binarization plays a key role in preprocess of recognizing cartridges in the ballistic imaging systems. Unfortunately, it is very difficult to get the satisfactory binary image using existing binary algorithms. In this paper, we utilize the global and local thresholds to enhance the image binarization. Importantly, we present a novel criterion for effectively detecting edges in the images. Comprehensive experiments have been conducted over sample ballistic images. The empirical results demonstrate the proposed method can provide a better solution than existing binary algorithms.

  15. 15 CFR 744.3 - Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch vehicles and sounding rockets) and Unmanned Air...: END-USER AND END-USE BASED § 744.3 Restrictions on Certain Rocket Systems (including ballistic missile...

  16. 15 CFR 744.3 - Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch vehicles and sounding rockets) and Unmanned Air...: END-USER AND END-USE BASED § 744.3 Restrictions on Certain Rocket Systems (including ballistic missile...

  17. 15 CFR 744.3 - Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 2 2013-01-01 2013-01-01 false Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch vehicles and sounding rockets) and Unmanned Air...: END-USER AND END-USE BASED § 744.3 Restrictions on Certain Rocket Systems (including ballistic missile...

  18. 15 CFR 744.3 - Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 2 2014-01-01 2014-01-01 false Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch vehicles and sounding rockets) and Unmanned Air...: END-USER AND END-USE BASED § 744.3 Restrictions on Certain Rocket Systems (including ballistic missile...

  19. 15 CFR 744.3 - Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Restrictions on Certain Rocket Systems (including ballistic missile systems and space launch vehicles and sounding rockets) and Unmanned Air...: END-USER AND END-USE BASED § 744.3 Restrictions on Certain Rocket Systems (including ballistic missile...

  20. Effects of acute static, ballistic, and PNF stretching exercise on the muscle and tendon tissue properties.

    PubMed

    Konrad, A; Stafilidis, S; Tilp, M

    2017-10-01

    The purpose of this study was to investigate the influence of a single static, ballistic, or proprioceptive neuromuscular facilitation (PNF) stretching exercise on the various muscle-tendon parameters of the lower leg and to detect possible differences in the effects between the methods. Volunteers (n = 122) were randomly divided into static, ballistic, and PNF stretching groups and a control group. Before and after the 4 × 30 s stretching intervention, we determined the maximum dorsiflexion range of motion (RoM) with the corresponding fascicle length and pennation angle of the gastrocnemius medialis. Passive resistive torque (PRT) and maximum voluntary contraction (MVC) were measured with a dynamometer. Observation of muscle-tendon junction (MTJ) displacement with ultrasound allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate stiffness. Although RoM increased (static: +4.3%, ballistic: +4.5%, PNF: +3.5%), PRT (static: -11.4%, ballistic: -11.5%, PNF: -13,7%), muscle stiffness (static: -13.1%, ballistic: -20.3%, PNF: -20.2%), and muscle-tendon stiffness (static: -11.3%, ballistic: -10.5%, PNF: -13.7%) decreased significantly in all the stretching groups. Only in the PNF stretching group, the pennation angle in the stretched position (-4.2%) and plantar flexor MVC (-4.6%) decreased significantly. Multivariate analysis showed no clinically relevant difference between the stretching groups. The increase in RoM and the decrease in PRT and muscle-tendon stiffness could be explained by more compliant muscle tissue following a single static, ballistic, or PNF stretching exercise. © 2017 The Authors Scandinavian Journal of Medicine & Science In Sports Published by John Wiley & Sons Ltd.

  1. Potentiation Effects of Half-Squats Performed in a Ballistic or Nonballistic Manner.

    PubMed

    Suchomel, Timothy J; Sato, Kimitake; DeWeese, Brad H; Ebben, William P; Stone, Michael H

    2016-06-01

    This study examined and compared the acute effects of ballistic and nonballistic concentric-only half-squats (COHSs) on squat jump performance. Fifteen resistance-trained men performed a squat jump 2 minutes after a control protocol or 2 COHSs at 90% of their 1 repetition maximum (1RM) COHS performed in a ballistic or nonballistic manner. Jump height (JH), peak power (PP), and allometrically scaled peak power (PPa) were compared using three 3 × 2 repeated-measures analyses of variance. Statistically significant condition × time interaction effects existed for JH (p = 0.037), PP (p = 0.041), and PPa (p = 0.031). Post hoc analysis revealed that the ballistic condition produced statistically greater JH (p = 0.017 and p = 0.036), PP (p = 0.031 and p = 0.026), and PPa (p = 0.024 and p = 0.023) than the control and nonballistic conditions, respectively. Small effect sizes for JH, PP, and PPa existed during the ballistic condition (d = 0.28-0.44), whereas trivial effect sizes existed during the control (d = 0.0-0.18) and nonballistic (d = 0.0-0.17) conditions. Large statistically significant relationships existed between the JH potentiation response and the subject's relative back squat 1RM (r = 0.520; p = 0.047) and relative COHS 1RM (r = 0.569; p = 0.027) during the ballistic condition. In addition, large statistically significant relationship existed between JH potentiation response and the subject's relative back squat strength (r = 0.633; p = 0.011), whereas the moderate relationship with the subject's relative COHS strength trended toward significance (r = 0.483; p = 0.068). Ballistic COHS produced superior potentiation effects compared with COHS performed in a nonballistic manner. Relative strength may contribute to the elicited potentiation response after ballistic and nonballistic COHS.

  2. Hazard map for volcanic ballistic impacts at El Chichón volcano (Mexico)

    NASA Astrophysics Data System (ADS)

    Alatorre-Ibarguengoitia, Miguel; Ramos-Hernández, Silvia; Jiménez-Aguilar, Julio

    2014-05-01

    The 1982 eruption of El Chichón Volcano in southeastern Mexico had a strong social and environmental impact. The eruption resulted in the worst volcanic disaster in the recorded history of Mexico, causing about 2,000 casualties, displacing thousands, and producing severe economic losses. Even when some villages were relocated after the 1982 eruption, many people still live and work in the vicinities of the volcano and may be affected in the case of a new eruption. The hazard map of El Chichón volcano (Macías et al., 2008) comprises pyroclastic flows, pyroclastic surges, lahars and ash fall but not ballistic projectiles, which represent an important threat to people, infrastructure and vegetation in the case of an eruption. In fact, the fatalities reported in the first stage of the 1982 eruption were caused by roof collapse induced by ashfall and lithic ballistic projectiles. In this study, a general methodology to delimit the hazard zones for volcanic ballistic projectiles during volcanic eruptions is applied to El Chichón volcano. Different scenarios are defined based on the past activity of the volcano and parameterized by considering the maximum kinetic energy associated with ballistic projectiles ejected during previous eruptions. A ballistic model is used to reconstruct the "launching" kinetic energy of the projectiles observed in the field. The maximum ranges expected for the ballistics in the different explosive scenarios defined for El Chichón volcano are presented in a ballistic hazard map which complements the published hazard map. These maps assist the responsible authorities to plan the definition and mitigation of restricted areas during volcanic crises.

  3. Heat guiding and focusing using ballistic phonon transport in phononic nanostructures

    NASA Astrophysics Data System (ADS)

    Anufriev, Roman; Ramiere, Aymeric; Maire, Jeremie; Nomura, Masahiro

    2017-05-01

    Unlike classical heat diffusion at macroscale, nanoscale heat conduction can occur without energy dissipation because phonons can ballistically travel in straight lines for hundreds of nanometres. Nevertheless, despite recent experimental evidence of such ballistic phonon transport, control over its directionality, and thus its practical use, remains a challenge, as the directions of individual phonons are chaotic. Here, we show a method to control the directionality of ballistic phonon transport using silicon membranes with arrays of holes. First, we demonstrate that the arrays of holes form fluxes of phonons oriented in the same direction. Next, we use these nanostructures as directional sources of ballistic phonons and couple the emitted phonons into nanowires. Finally, we introduce thermal lens nanostructures, in which the emitted phonons converge at the focal point, thus focusing heat into a spot of a few hundred nanometres. These results motivate the concept of ray-like heat manipulations at the nanoscale.

  4. Ballistic Jumping Drops on Superhydrophobic Surfaces via Electrostatic Manipulation.

    PubMed

    Li, Ning; Wu, Lei; Yu, Cunlong; Dai, Haoyu; Wang, Ting; Dong, Zhichao; Jiang, Lei

    2018-02-01

    The ballistic ejection of liquid drops by electrostatic manipulating has both fundamental and practical implications, from raindrops in thunderclouds to self-cleaning, anti-icing, condensation, and heat transfer enhancements. In this paper, the ballistic jumping behavior of liquid drops from a superhydrophobic surface is investigated. Powered by the repulsion of the same kind of charges, water drops can jump from the surface. The electrostatic acting time for the jumping of a microliter supercooled drop only takes several milliseconds, even shorter than the time for icing. In addition, one can control the ballistic jumping direction precisely by the relative position above the electrostatic field. The approach offers a facile method that can be used to manipulate the ballistic drop jumping via an electrostatic field, opening the possibility of energy efficient drop detaching techniques in various applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Heat guiding and focusing using ballistic phonon transport in phononic nanostructures.

    PubMed

    Anufriev, Roman; Ramiere, Aymeric; Maire, Jeremie; Nomura, Masahiro

    2017-05-18

    Unlike classical heat diffusion at macroscale, nanoscale heat conduction can occur without energy dissipation because phonons can ballistically travel in straight lines for hundreds of nanometres. Nevertheless, despite recent experimental evidence of such ballistic phonon transport, control over its directionality, and thus its practical use, remains a challenge, as the directions of individual phonons are chaotic. Here, we show a method to control the directionality of ballistic phonon transport using silicon membranes with arrays of holes. First, we demonstrate that the arrays of holes form fluxes of phonons oriented in the same direction. Next, we use these nanostructures as directional sources of ballistic phonons and couple the emitted phonons into nanowires. Finally, we introduce thermal lens nanostructures, in which the emitted phonons converge at the focal point, thus focusing heat into a spot of a few hundred nanometres. These results motivate the concept of ray-like heat manipulations at the nanoscale.

  6. Heat guiding and focusing using ballistic phonon transport in phononic nanostructures

    PubMed Central

    Anufriev, Roman; Ramiere, Aymeric; Maire, Jeremie; Nomura, Masahiro

    2017-01-01

    Unlike classical heat diffusion at macroscale, nanoscale heat conduction can occur without energy dissipation because phonons can ballistically travel in straight lines for hundreds of nanometres. Nevertheless, despite recent experimental evidence of such ballistic phonon transport, control over its directionality, and thus its practical use, remains a challenge, as the directions of individual phonons are chaotic. Here, we show a method to control the directionality of ballistic phonon transport using silicon membranes with arrays of holes. First, we demonstrate that the arrays of holes form fluxes of phonons oriented in the same direction. Next, we use these nanostructures as directional sources of ballistic phonons and couple the emitted phonons into nanowires. Finally, we introduce thermal lens nanostructures, in which the emitted phonons converge at the focal point, thus focusing heat into a spot of a few hundred nanometres. These results motivate the concept of ray-like heat manipulations at the nanoscale. PMID:28516909

  7. Design Guide for Aerodynamics Testing of Earth and Planetary Entry Vehicles in a Ballistic Range

    NASA Technical Reports Server (NTRS)

    Bogdanoff, David W.

    2017-01-01

    The purpose of this manual is to aid in the design of an aerodynamics test of an earth or planetary entry capsule in a ballistic range. In this manual, much use is made of the results and experience gained in 50 years of ballistic range aerodynamics testing at the NASA Ames Research Center, and in particular, that gained in the last 27 years, while the author was working at NASA Ames. The topics treated herein include: Data to be obtained; flight data needed to design test; Reynolds number and dynamic similarity of flight trajectory and ballistic range test; capabilities of various ballistic ranges; Calculations of swerves due to average and oscillating lift and of drag-induced velocity decreases; Model and sabot design; materials, weights and stresses; Sabot separation; Launches at angle of attack and slapping with paper to produce pitch/yaw oscillations.

  8. Schottky barrier height measurements of Cu/Si(001), Ag/Si(001), and Au/Si(001) interfaces utilizing ballistic electron emission microscopy and ballistic hole emission microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balsano, Robert; Matsubayashi, Akitomo; LaBella, Vincent P., E-mail: vlabella@albany.edu

    2013-11-15

    The Schottky barrier heights of both n and p doped Cu/Si(001), Ag/Si(001), and Au/Si(001) diodes were measured using ballistic electron emission microscopy and ballistic hole emission microscopy (BHEM), respectively. Measurements using both forward and reverse ballistic electron emission microscopy (BEEM) and (BHEM) injection conditions were performed. The Schottky barrier heights were found by fitting to a linearization of the power law form of the Bell-Kaiser BEEM model. The sum of the n-type and p-type barrier heights are in good agreement with the band gap of silicon and independent of the metal utilized. The Schottky barrier heights are found to bemore » below the region of best fit for the power law form of the BK model, demonstrating its region of validity.« less

  9. Ballistic Analysis of New Military Grade Magnesium Alloys for Armor Applications

    NASA Astrophysics Data System (ADS)

    Jones, Tyrone L.; Kondoh, Katsuyoshi

    Since 2006, the U.S. Army has been evaluating magnesium (Mg) alloys for ballistic structural applications. While Mg-alloys have been used in military structural applications since WWII, very little research has been done to improve its mediocre ballistic performance. The Army's need for ultra-lightweight armor systems has led to research and development of high strength, high ductility Mg-alloys. The U.S. Army Research Laboratory contracted through International Technology Center-Pacific Contract Number FA-5209-09-P-0158 with the Joining and Welding Research Instituteof Osaka University to develop the next generation of high strength, high ductility Mg-alloys using a novel Spinning Water Atomization Process for rapid solidification. New alloys AMX602 and ZAXE1711 in extruded bar form were characterized for microstructure, mechanical, and ballistic response. Significant increases in ballistic performance were evident when compared to the baseline alloy AZ31B.

  10. Initial Validation of Ballistic Shock Transducers

    DTIC Science & Technology

    2017-06-05

    objective of this TOP is to describe various methods and instrumentation used in the initial validation of accelerometers to be used in both Ballistic...MILITARY STANDARD 810G CHANGE NOTICE 1, METHOD 522.2, SECTION 4.4.2 ....................................... A-1 B. GLOSSARY...Procedure (TOP) is to describe various methods and instrumentation used in the initial validation of accelerometers to be used in both Ballistic

  11. 26th International Symposium on Ballistics

    DTIC Science & Technology

    2011-09-16

    judicious use of analytical predictions correlated with ballistic testing and post - test failure morphology investigations. •Our approach...ballistic predictions. The numerical predictions correlate well with the damage pattern. Post - Test Morphology Simulation Imbedded Steel Plate Removed Post ... Test •Numerical simulation of damage to embedded steel plate compares well with the post - test plate morphology •Multi-strike modeling in work

  12. Airborne ballistic camera tracking systems

    NASA Technical Reports Server (NTRS)

    Redish, W. L.

    1976-01-01

    An operational airborne ballistic camera tracking system was tested for operational and data reduction feasibility. The acquisition and data processing requirements of the system are discussed. Suggestions for future improvements are also noted. A description of the data reduction mathematics is outlined. Results from a successful reentry test mission are tabulated. The test mission indicated that airborne ballistic camera tracking systems are feasible.

  13. Ballistic trauma: lessons learned from iraq and afghanistan.

    PubMed

    Shin, Emily H; Sabino, Jennifer M; Nanos, George P; Valerio, Ian L

    2015-02-01

    Management of upper extremity injuries secondary to ballistic and blast trauma can lead to challenging problems for the reconstructive surgeon. Given the recent conflicts in Iraq and Afghanistan, advancements in combat-casualty care, combined with a high-volume experience in the treatment of ballistic injuries, has led to continued advancements in the treatment of the severely injured upper extremity. There are several lessons learned that are translatable to civilian trauma centers and future conflicts. In this article, the authors provide an overview of the physics of ballistic injuries and principles in the management of such injuries through experience gained from military involvement in Iraq and Afghanistan.

  14. Ballistic anisotropic magnetoresistance in core-shell nanowires and rolled-up nanotubes

    NASA Astrophysics Data System (ADS)

    Chang, Ching-Hao; Ortix, Carmine

    2017-01-01

    In ferromagnetic nanostructures, the ballistic anisotropic magnetoresistance (BAMR) is a change in the ballistic conductance with the direction of magnetization due to spin-orbit interaction. Very recently, a directional dependent ballistic conductance has been predicted to occur in a number of newly synthesized nonmagnetic semiconducting nanostructures subject to externally applied magnetic fields, without necessitating spin-orbit coupling. In this paper, we review past works on the prediction of this BAMR effect in core-shell nanowires (CSN) and rolled-up nanotubes (RUNTs). This is complemented by new results, we establish for the transport properties of tubular nanosystems subject to external magnetic fields.

  15. Ballistic Trauma: Lessons Learned from Iraq and Afghanistan

    PubMed Central

    Shin, Emily H.; Sabino, Jennifer M.; Nanos, George P.; Valerio, Ian L.

    2015-01-01

    Management of upper extremity injuries secondary to ballistic and blast trauma can lead to challenging problems for the reconstructive surgeon. Given the recent conflicts in Iraq and Afghanistan, advancements in combat-casualty care, combined with a high-volume experience in the treatment of ballistic injuries, has led to continued advancements in the treatment of the severely injured upper extremity. There are several lessons learned that are translatable to civilian trauma centers and future conflicts. In this article, the authors provide an overview of the physics of ballistic injuries and principles in the management of such injuries through experience gained from military involvement in Iraq and Afghanistan. PMID:25685099

  16. Comparative Ballistic Performance of 20mm AP M95 and 20mm AP M75 Projectiles against Rolled Homogeneous Steel Armor

    DTIC Science & Technology

    1960-05-01

    Dominic A. Piccione, " Comparative Ballistic Performanceof 20mm AP M95 and 20mm AP M75 Projectiles againstRolled Homogeneous Steel Armor (U)’\\ WAL-TR-160.1/1... COMPARATIVE BALLISTIC PERFORMANCE OF 20MM AP M95 AND 20MM AP M75 PROJECTILES AGAINST ROLLED HOMOGENEOUS STEEL ARMOR (U) TECHNICAL REPORT NO. WAL TR I60.l/I(c...o > -< Abt9sortf bl O *_, o o -o WATERTOWN ARSENAL LABORATORIES co COMPARATIVE BALLISTIC PERFORMANCE OF 20MM AP M95 AND 20MM AP M75

  17. Ballistic Resistance of Honeycomb Sandwich Panels under In-Plane High-Velocity Impact

    PubMed Central

    Yang, Shu; Wang, Dong; Yang, Li-Jun

    2013-01-01

    The dynamic responses of honeycomb sandwich panels (HSPs) subjected to in-plane projectile impact were studied by means of explicit nonlinear finite element simulations using LS-DYNA. The HSPs consisted of two identical aluminum alloy face-sheets and an aluminum honeycomb core featuring three types of unit cell configurations (regular, rectangular-shaped, and reentrant hexagons). The ballistic resistances of HSPs with the three core configurations were first analyzed. It was found that the HSP with the reentrant auxetic honeycomb core has the best ballistic resistance, due to the negative Poisson's ratio effect of the core. Parametric studies were then carried out to clarify the influences of both macroscopic (face-sheet and core thicknesses, core relative density) and mesoscopic (unit cell angle and size) parameters on the ballistic responses of the auxetic HSPs. Numerical results show that the perforation resistant capabilities of the auxetic HSPs increase as the values of the macroscopic parameters increase. However, the mesoscopic parameters show nonmonotonic effects on the panels' ballistic capacities. The empirical equations for projectile residual velocities were formulated in terms of impact velocity and the structural parameters. It was also found that the blunter projectiles result in higher ballistic limits of the auxetic HSPs. PMID:24187526

  18. Nonlinear Ballistic Transport in an Atomically Thin Material.

    PubMed

    Boland, Mathias J; Sundararajan, Abhishek; Farrokhi, M Javad; Strachan, Douglas R

    2016-01-26

    Ultrashort devices that incorporate atomically thin components have the potential to be the smallest electronics. Such extremely scaled atomically thin devices are expected to show ballistic nonlinear behavior that could make them tremendously useful for ultrafast applications. While nonlinear diffusive electron transport has been widely reported, clear evidence for intrinsic nonlinear ballistic transport in the growing array of atomically thin conductors has so far been elusive. Here we report nonlinear electron transport of an ultrashort single-layer graphene channel that shows quantitative agreement with intrinsic ballistic transport. This behavior is shown to be distinctly different than that observed in similarly prepared ultrashort devices consisting, instead, of bilayer graphene channels. These results suggest that the addition of only one extra layer of an atomically thin material can make a significant impact on the nonlinear ballistic behavior of ultrashort devices, which is possibly due to the very different chiral tunneling of their charge carriers. The fact that we observe the nonlinear ballistic response at room temperature, with zero applied magnetic field, in non-ultrahigh vacuum conditions and directly on a readily accessible oxide substrate makes the nanogap technology we utilize of great potential for achieving extremely scaled high-speed atomically thin devices.

  19. Time-gated ballistic imaging using a large aperture switching beam.

    PubMed

    Mathieu, Florian; Reddemann, Manuel A; Palmer, Johannes; Kneer, Reinhold

    2014-03-24

    Ballistic imaging commonly denotes the formation of line-of-sight shadowgraphs through turbid media by suppression of multiply scattered photons. The technique relies on a femtosecond laser acting as light source for the images and as switch for an optical Kerr gate that separates ballistic photons from multiply scattered ones. The achievable image resolution is one major limitation for the investigation of small objects. In this study, practical influences on the optical Kerr gate and image quality are discussed theoretically and experimentally applying a switching beam with large aperture (D = 19 mm). It is shown how switching pulse energy and synchronization of switching and imaging pulse in the Kerr cell influence the gate's transmission. Image quality of ballistic imaging and standard shadowgraphy is evaluated and compared, showing that the present ballistic imaging setup is advantageous for optical densities in the range of 8 < OD < 13. Owing to the spatial transmission characteristics of the optical Kerr gate, a rectangular aperture stop is formed, which leads to different resolution limits for vertical and horizontal structures in the object. Furthermore, it is reported how to convert the ballistic imaging setup into a schlieren-type system with an optical schlieren edge.

  20. Supercurrent and multiple Andreev reflections in micrometer-long ballistic graphene Josephson junctions.

    PubMed

    Zhu, Mengjian; Ben Shalom, Moshe; Mishchsenko, Artem; Fal'ko, Vladimir; Novoselov, Kostya; Geim, Andre

    2018-02-08

    Ballistic Josephson junctions are predicted to support a number of exotic physics processess, providing an ideal system to inject the supercurrent in the quantum Hall regime. Herein, we demonstrate electrical transport measurements on ballistic superconductor-graphene-superconductor junctions by contacting graphene to niobium with a junction length up to 1.5 μm. Hexagonal boron nitride encapsulation and one-dimensional edge contacts guarantee high-quality graphene Josephson junctions with a mean free path of several micrometers and record-low contact resistance. Transports in normal states including the observation of Fabry-Pérot oscillations and Sharvin resistance conclusively witness the ballistic propagation in the junctions. The critical current density J C is over one order of magnitude larger than that of the previously reported junctions. Away from the charge neutrality point, the I C R N product (I C is the critical current and R N the normal state resistance of junction) is nearly a constant, independent of carrier density n, which agrees well with the theory for ballistic Josephson junctions. Multiple Andreev reflections up to the third order are observed for the first time by measuring the differential resistance in the micrometer-long ballistic graphene Josephson junctions.

  1. Ballistic resistance of honeycomb sandwich panels under in-plane high-velocity impact.

    PubMed

    Qi, Chang; Yang, Shu; Wang, Dong; Yang, Li-Jun

    2013-01-01

    The dynamic responses of honeycomb sandwich panels (HSPs) subjected to in-plane projectile impact were studied by means of explicit nonlinear finite element simulations using LS-DYNA. The HSPs consisted of two identical aluminum alloy face-sheets and an aluminum honeycomb core featuring three types of unit cell configurations (regular, rectangular-shaped, and reentrant hexagons). The ballistic resistances of HSPs with the three core configurations were first analyzed. It was found that the HSP with the reentrant auxetic honeycomb core has the best ballistic resistance, due to the negative Poisson's ratio effect of the core. Parametric studies were then carried out to clarify the influences of both macroscopic (face-sheet and core thicknesses, core relative density) and mesoscopic (unit cell angle and size) parameters on the ballistic responses of the auxetic HSPs. Numerical results show that the perforation resistant capabilities of the auxetic HSPs increase as the values of the macroscopic parameters increase. However, the mesoscopic parameters show nonmonotonic effects on the panels' ballistic capacities. The empirical equations for projectile residual velocities were formulated in terms of impact velocity and the structural parameters. It was also found that the blunter projectiles result in higher ballistic limits of the auxetic HSPs.

  2. Estimation of ballistic block landing energy during 2014 Mount Ontake eruption

    NASA Astrophysics Data System (ADS)

    Tsunematsu, Kae; Ishimine, Yasuhiro; Kaneko, Takayuki; Yoshimoto, Mitsuhiro; Fujii, Toshitsugu; Yamaoka, Koshun

    2016-05-01

    The 2014 Mount Ontake eruption started just before noon on September 27, 2014. It killed 58 people, and five are still missing (as of January 1, 2016). The casualties were mainly caused by the impact of ballistic blocks around the summit area. It is necessary to know the magnitude of the block velocity and energy to construct a hazard map of ballistic projectiles and design effective shelters and mountain huts. The ejection velocities of the ballistic projectiles were estimated by comparing the observed distribution of the ballistic impact craters on the ground with simulated distributions of landing positions under various sets of conditions. A three-dimensional numerical multiparticle ballistic model adapted to account for topographic effect was used to estimate the ejection angles. From these simulations, we have obtained an ejection angle of γ = 20° from vertical to horizontal and α = 20° from north to east. With these ejection angle conditions, the ejection speed was estimated to be between 145 and 185 m/s for a previously obtained range of drag coefficients of 0.62-1.01. The order of magnitude of the mean landing energy obtained using our numerical simulation was 104 J.

  3. Analysis of pressure blips in aft-finocyl solid rocket motor

    NASA Astrophysics Data System (ADS)

    Di Giacinto, M.; Favini, B.; Cavallini, E.

    2016-07-01

    Ballistic anomalies have frequently occurred during the firing of several solid rocket motors (SRMs) (Inertial Upper Stage, Space Shuttle Redesigned SRM (RSRM) and Titan IV SRM Upgrade (SRMU)), producing even relevant and unexpected variations of the SRM pressure trace from its nominal profile. This paper has the purpose to provide a numerical analysis of the following possible causes of ballistic anomalies in SRMs: an inert object discharge, a slag ejection, and an unexpected increase in the propellant burning rate or in the combustion surface. The SRM configuration under investigation is an aft-finocyl SRM with a first-stage/small booster design. The numerical simulations are performed with a quasi-one-dimensional (Q1D) unsteady model of the SRM internal ballistics, properly tailored to model each possible cause of the ballistic anomalies. The results have shown that a classification based on the head-end pressure (HEP) signature, relating each other the HEP shape and the ballistic anomaly cause, can be made. For each cause of ballistic anomalies, a deepened discussion of the parameters driving the HEP signatures is provided, as well as qualitative and quantitative assessments of the resultant pressure signals.

  4. Verification of models for ballistic movement time and endpoint variability.

    PubMed

    Lin, Ray F; Drury, Colin G

    2013-01-01

    A hand control movement is composed of several ballistic movements. The time required in performing a ballistic movement and its endpoint variability are two important properties in developing movement models. The purpose of this study was to test potential models for predicting these two properties. Twelve participants conducted ballistic movements of specific amplitudes using a drawing tablet. The measured data of movement time and endpoint variability were then used to verify the models. This study was successful with Hoffmann and Gan's movement time model (Hoffmann, 1981; Gan and Hoffmann 1988) predicting more than 90.7% data variance for 84 individual measurements. A new theoretically developed ballistic movement variability model, proved to be better than Howarth, Beggs, and Bowden's (1971) model, predicting on average 84.8% of stopping-variable error and 88.3% of aiming-variable errors. These two validated models will help build solid theoretical movement models and evaluate input devices. This article provides better models for predicting end accuracy and movement time of ballistic movements that are desirable in rapid aiming tasks, such as keying in numbers on a smart phone. The models allow better design of aiming tasks, for example button sizes on mobile phones for different user populations.

  5. 2005 22nd International Symposium on Ballistics. Volume 3 Thursday - Friday

    DTIC Science & Technology

    2005-11-18

    QinetiQ; Vladimir Titarev, Eleuterio Toro , Umeritek Limited The Mechanism Analysis of Interior Ballistics of Serial Chamber Gun, Dr. Sanjiu Ying, Charge...Elements and Meshless Particles, Gordon R. Johnson and Robert A. Stryk, Network Computing Services, Inc. Experimental and Numerical Study of the...Internal Ballistics Clive R. Woodley, David Finbow, QinetiQ; Vladimir Titarev, Eleuterio Toro , Numeritek Limited 22nd International Symposium on

  6. Conventional Prompt Global Strike and Long Range Ballistic Missiles: Background and Issues

    DTIC Science & Technology

    2017-02-03

    Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues Amy F. Woolf Specialist in Nuclear Weapons Policy...February 3, 2017 Congressional Research Service 7-5700 www.crs.gov R41464 Conventional Prompt Global Strike and Long-Range Ballistic Missiles...Congressional Research Service Summary Conventional prompt global strike (CPGS) weapons would allow the United States to strike targets anywhere

  7. Ballistic Characterization of the Scalability of Magnesium Alloy AMX602

    DTIC Science & Technology

    2015-07-01

    Powder Metallurgy 4 5. Fabrication Procedure 4 6. Mechanical Property Analysis 5 7. Ballistic Experimental Procedures 6 8. Ballistic Experimental...compositions of noncombustive Mg alloy powders 4. Powder Metallurgy The powder was consolidated at room temperature using a 2,000-kN hydraulic press...evaluation of advanced powder metallurgy magnesium alloys for dynamic applications. Aberdeen Proving Ground (MD): Army Research Laboratory (US); 2009 May

  8. Ballistic Graphene Josephson Junctions from the Short to the Long Junction Regimes.

    PubMed

    Borzenets, I V; Amet, F; Ke, C T; Draelos, A W; Wei, M T; Seredinski, A; Watanabe, K; Taniguchi, T; Bomze, Y; Yamamoto, M; Tarucha, S; Finkelstein, G

    2016-12-02

    We investigate the critical current I_{C} of ballistic Josephson junctions made of encapsulated graphene-boron-nitride heterostructures. We observe a crossover from the short to the long junction regimes as the length of the device increases. In long ballistic junctions, I_{C} is found to scale as ∝exp(-k_{B}T/δE). The extracted energies δE are independent of the carrier density and proportional to the level spacing of the ballistic cavity. As T→0 the critical current of a long (or short) junction saturates at a level determined by the product of δE (or Δ) and the number of the junction's transversal modes.

  9. Characteristic extraction and matching algorithms of ballistic missile in near-space by hyperspectral image analysis

    NASA Astrophysics Data System (ADS)

    Lu, Li; Sheng, Wen; Liu, Shihua; Zhang, Xianzhi

    2014-10-01

    The ballistic missile hyperspectral data of imaging spectrometer from the near-space platform are generated by numerical method. The characteristic of the ballistic missile hyperspectral data is extracted and matched based on two different kinds of algorithms, which called transverse counting and quantization coding, respectively. The simulation results show that two algorithms extract the characteristic of ballistic missile adequately and accurately. The algorithm based on the transverse counting has the low complexity and can be implemented easily compared to the algorithm based on the quantization coding does. The transverse counting algorithm also shows the good immunity to the disturbance signals and speed up the matching and recognition of subsequent targets.

  10. High Resolution, High-Speed Photography, an Increasingly Prominent Diagnostic in Ballistic Research Experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shaw, L.; Muelder, S.

    1999-10-22

    High resolution, high-speed photography is becoming a prominent diagnostic in ballistic experimentation. The development of high speed cameras utilizing electro-optics and the use of lasers for illumination now provide the capability to routinely obtain high quality photographic records of ballistic style experiments. The purpose of this presentation is to review in a visual manner the progress of this technology and how it has impacted ballistic experimentation. Within the framework of development at LLNL, we look at the recent history of large format high-speed photography, and present a number of photographic records that represent the state of the art at themore » time they were made. These records are primarily from experiments involving shaped charges. We also present some examples of current photographic technology, developed within the ballistic community, that has application to hydro diagnostic experimentation at large. This paper is designed primarily as an oral-visual presentation. This written portion is to provide general background, a few examples, and a bibliography.« less

  11. Transition from normal to ballistic diffusion in a one-dimensional impact system

    NASA Astrophysics Data System (ADS)

    Livorati, André L. P.; Kroetz, Tiago; Dettmann, Carl P.; Caldas, Iberê L.; Leonel, Edson D.

    2018-03-01

    We characterize a transition from normal to ballistic diffusion in a bouncing ball dynamics. The system is composed of a particle, or an ensemble of noninteracting particles, experiencing elastic collisions with a heavy and periodically moving wall under the influence of a constant gravitational field. The dynamics lead to a mixed phase space where chaotic orbits have a free path to move along the velocity axis, presenting a normal diffusion behavior. Depending on the control parameter, one can observe the presence of featured resonances, known as accelerator modes, that lead to a ballistic growth of velocity. Through statistical and numerical analysis of the velocity of the particle, we are able to characterize a transition between the two regimes, where transport properties were used to characterize the scenario of the ballistic regime. Also, in an analysis of the probability of an orbit to reach an accelerator mode as a function of the velocity, we observe a competition between the normal and ballistic transport in the midrange velocity.

  12. Injuries of the head from backface deformation of ballistic protective helmets under ballistic impact.

    PubMed

    Rafaels, Karin A; Cutcliffe, Hattie C; Salzar, Robert S; Davis, Martin; Boggess, Brian; Bush, Bryan; Harris, Robert; Rountree, Mark Steve; Sanderson, Ellory; Campman, Steven; Koch, Spencer; Dale Bass, Cameron R

    2015-01-01

    Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed "behind armor blunt trauma" (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400-460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear. © 2014 American Academy of Forensic Sciences.

  13. Ballistic One-Dimensional InAs Nanowire Cross-Junction Interconnects.

    PubMed

    Gooth, Johannes; Borg, Mattias; Schmid, Heinz; Schaller, Vanessa; Wirths, Stephan; Moselund, Kirsten; Luisier, Mathieu; Karg, Siegfried; Riel, Heike

    2017-04-12

    Coherent interconnection of quantum bits remains an ongoing challenge in quantum information technology. Envisioned hardware to achieve this goal is based on semiconductor nanowire (NW) circuits, comprising individual NW devices that are linked through ballistic interconnects. However, maintaining the sensitive ballistic conduction and confinement conditions across NW intersections is a nontrivial problem. Here, we go beyond the characterization of a single NW device and demonstrate ballistic one-dimensional (1D) quantum transport in InAs NW cross-junctions, monolithically integrated on Si. Characteristic 1D conductance plateaus are resolved in field-effect measurements across up to four NW-junctions in series. The 1D ballistic transport and sub-band splitting is preserved for both crossing-directions. We show that the 1D modes of a single injection terminal can be distributed into multiple NW branches. We believe that NW cross-junctions are well-suited as cross-directional communication links for the reliable transfer of quantum information as required for quantum computational systems.

  14. Coherent Control of Nanoscale Ballistic Currents in Transition Metal Dichalcogenide ReS2.

    PubMed

    Cui, Qiannan; Zhao, Hui

    2015-04-28

    Transition metal dichalcogenides are predicted to outperform traditional semiconductors in ballistic devices with nanoscale channel lengths. So far, experimental studies on charge transport in transition metal dichalcogenides are limited to the diffusive regime. Here we show, using ReS2 as an example, all-optical injection, detection, and coherent control of ballistic currents. By utilizing quantum interference between one-photon and two-photon interband transition pathways, ballistic currents are injected in ReS2 thin film samples by a pair of femtosecond laser pulses. We find that the current decays on an ultrafast time scale, resulting in an electron transport of only a fraction of one nanometer. Following the relaxation of the initially injected momentum, backward motion of the electrons for about 1 ps is observed, driven by the Coulomb force from the oppositely moved holes. We also show that the injected current can be controlled by the phase of the laser pulses. These results demonstrate a new platform to study ballistic transport of nonequilibrium carriers in transition metal dichalcogenides.

  15. Transition from normal to ballistic diffusion in a one-dimensional impact system.

    PubMed

    Livorati, André L P; Kroetz, Tiago; Dettmann, Carl P; Caldas, Iberê L; Leonel, Edson D

    2018-03-01

    We characterize a transition from normal to ballistic diffusion in a bouncing ball dynamics. The system is composed of a particle, or an ensemble of noninteracting particles, experiencing elastic collisions with a heavy and periodically moving wall under the influence of a constant gravitational field. The dynamics lead to a mixed phase space where chaotic orbits have a free path to move along the velocity axis, presenting a normal diffusion behavior. Depending on the control parameter, one can observe the presence of featured resonances, known as accelerator modes, that lead to a ballistic growth of velocity. Through statistical and numerical analysis of the velocity of the particle, we are able to characterize a transition between the two regimes, where transport properties were used to characterize the scenario of the ballistic regime. Also, in an analysis of the probability of an orbit to reach an accelerator mode as a function of the velocity, we observe a competition between the normal and ballistic transport in the midrange velocity.

  16. Ballistic edge states in Bismuth nanowires revealed by SQUID interferometry.

    PubMed

    Murani, Anil; Kasumov, Alik; Sengupta, Shamashis; Kasumov, Yu A; Volkov, V T; Khodos, I I; Brisset, F; Delagrange, Raphaëlle; Chepelianskii, Alexei; Deblock, Richard; Bouchiat, Hélène; Guéron, Sophie

    2017-07-05

    The protection against backscattering provided by topology is a striking property. In two-dimensional insulators, a consequence of this topological protection is the ballistic nature of the one-dimensional helical edge states. One demonstration of ballisticity is the quantized Hall conductance. Here we provide another demonstration of ballistic transport, in the way the edge states carry a supercurrent. The system we have investigated is a micrometre-long monocrystalline bismuth nanowire with topological surfaces, that we connect to two superconducting electrodes. We have measured the relation between the Josephson current flowing through the nanowire and the superconducting phase difference at its ends, the current-phase relation. The sharp sawtooth-shaped phase-modulated current-phase relation we find demonstrates that transport occurs selectively along two ballistic edges of the nanowire. In addition, we show that a magnetic field induces 0-π transitions and ϕ 0 -junction behaviour, providing a way to manipulate the phase of the supercurrent-carrying edge states and generate spin supercurrents.

  17. Ballistic edge states in Bismuth nanowires revealed by SQUID interferometry

    PubMed Central

    Murani, Anil; Kasumov, Alik; Sengupta, Shamashis; Kasumov, Yu A.; Volkov, V. T.; Khodos, I. I.; Brisset, F.; Delagrange, Raphaëlle; Chepelianskii, Alexei; Deblock, Richard; Bouchiat, Hélène; Guéron, Sophie

    2017-01-01

    The protection against backscattering provided by topology is a striking property. In two-dimensional insulators, a consequence of this topological protection is the ballistic nature of the one-dimensional helical edge states. One demonstration of ballisticity is the quantized Hall conductance. Here we provide another demonstration of ballistic transport, in the way the edge states carry a supercurrent. The system we have investigated is a micrometre-long monocrystalline bismuth nanowire with topological surfaces, that we connect to two superconducting electrodes. We have measured the relation between the Josephson current flowing through the nanowire and the superconducting phase difference at its ends, the current–phase relation. The sharp sawtooth-shaped phase-modulated current–phase relation we find demonstrates that transport occurs selectively along two ballistic edges of the nanowire. In addition, we show that a magnetic field induces 0–π transitions and φ0-junction behaviour, providing a way to manipulate the phase of the supercurrent-carrying edge states and generate spin supercurrents. PMID:28677681

  18. A Ballistics Examination of Firearm Injuries Involving Breast Implants.

    PubMed

    Pannucci, Christopher J; Cyr, Adam J; Moores, Neal G; Young, Jason B; Szegedi, Martin

    2018-03-01

    This ballistics study examines whether saline breast implants can decrease tissue penetration in firearm injuries. We hypothesize that the fluid column within a saline breast implant can alter bullet velocity and/or bullet pattern of mushrooming. The two experimental groups included saline implants with 7.4 cm projection and a no implant group. The experimental design allowed the bullet to pass-through an implant and into ballistics gel (n = 10) or into ballistics gel without passage through an implant (n = 11). Shots that passed through an implant had 20.6% decreased penetration distance when compared to shots that did not pass-through an implant; this difference was statistically significant (31.9 cm vs. 40.2 cm, p < 0.001). Implant group bullets mushroomed prior to gel entry, but the no implant group mushroomed within the gel. Bullet passage through a saline breast implant results in direct bullet velocity reduction and earlier bullet mushrooming; this causes significantly decreased ballistics gel penetration. © 2017 American Academy of Forensic Sciences.

  19. Applications of computational modeling in ballistics

    NASA Technical Reports Server (NTRS)

    Sturek, Walter B.

    1987-01-01

    The development of the technology of ballistics as applied to gun launched Army weapon systems is the main objective of research at the U.S. Army Ballistic Research Laboratory (BRL). The primary research programs at the BRL consist of three major ballistic disciplines: exterior, interior, and terminal. The work done at the BRL in these areas was traditionally highly dependent on experimental testing. A considerable emphasis was placed on the development of computational modeling to augment the experimental testing in the development cycle; however, the impact of the computational modeling to this date is modest. With the availability of supercomputer computational resources recently installed at the BRL, a new emphasis on the application of computational modeling to ballistics technology is taking place. The major application areas are outlined which are receiving considerable attention at the BRL at present and to indicate the modeling approaches involved. An attempt was made to give some information as to the degree of success achieved and indicate the areas of greatest need.

  20. Magneto-ballistic transport in GaN nanowires

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Santoruvo, Giovanni, E-mail: giovanni.santoruvo@epfl.ch; Allain, Adrien; Ovchinnikov, Dmitry

    2016-09-05

    The ballistic filtering property of nanoscale crosses was used to investigate the effect of perpendicular magnetic fields on the ballistic transport of electrons on wide band-gap GaN heterostructures. The straight scattering-less trajectory of electrons was modified by a perpendicular magnetic field which produced a strong non-linear behavior in the measured output voltage of the ballistic filters and allowed the observation of semi-classical and quantum effects, such as quenching of the Hall resistance and manifestation of the last plateau, in excellent agreement with the theoretical predictions. A large measured phase coherence length of 190 nm allowed the observation of universal quantum fluctuationsmore » and weak localization of electrons due to quantum interference up to ∼25 K. This work also reveals the prospect of wide band-gap GaN semiconductors as a platform for basic transport and quantum studies, whose properties allow the investigation of ballistic transport and quantum phenomena at much larger voltages and temperatures than in other semiconductors.« less

  1. External Ballistics. Part 1

    DTIC Science & Technology

    1978-07-11

    trajectories and aEe gAven the concepts cf tke oEtiaua sclticas of the problems of e.termal ballistics. Is estimated the effect c different perturkation... development receimed the d*signed kallistic calculaticns ct scattering trajectoies bith the firiqg icckets and artillery shells. The application/use of...problems, solved in the course of external ballistics, they at* bscught informaticn fzca the histccl of the development of the thecrj of flight and

  2. Quantum Mechanical Modeling of Ballistic MOSFETs

    NASA Technical Reports Server (NTRS)

    Svizhenko, Alexei; Anantram, M. P.; Govindan, T. R.; Biegel, Bryan (Technical Monitor)

    2001-01-01

    The objective of this project was to develop theory, approximations, and computer code to model quasi 1D structures such as nanotubes, DNA, and MOSFETs: (1) Nanotubes: Influence of defects on ballistic transport, electro-mechanical properties, and metal-nanotube coupling; (2) DNA: Model electron transfer (biochemistry) and transport experiments, and sequence dependence of conductance; and (3) MOSFETs: 2D doping profiles, polysilicon depletion, source to drain and gate tunneling, understand ballistic limit.

  3. Investigation of Basalt Woven Fabrics for Military Applications

    DTIC Science & Technology

    2011-11-01

    investigates the use of basalt fibers in a composite along with SC-15 epoxy resin for ballistic protection. Basalt fibers are not known as a ballistic...material but rather as a structural one. Even though basalt fibers are not expected to outperform some of the higher ballistic performing materials...such as the aramid and polyethylene fibers ; however, due to the lower manufacturing costs, basalt fibers are an interesting alternative. The objective

  4. Obscuration Due to Dust of a Laser Beam in a Gun Firing Environment - Preliminary Survey

    DTIC Science & Technology

    1975-10-01

    34 APG- MT-4371, Nov 1973, Aberdeen Proving Ground , MD (AD Number: 915796L). 13. Engineering Design Handbook, Ballistic Series, "Interior Ballistics of...Technical Library Watervliet, NY 12189 Director Ballistic Research Laboratories Aberdeen Proving Ground , MD 21005 Commander US Army Electronics...RHFL Warren, MI 48090 Commander Aberdeen Proving Ground ATTN: Tech Lib., Bldg 313 Aberdeen Proving Ground , MD 22005 Chief of Naval Research

  5. Steering and collimating ballistic electrons with amphoteric refraction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Radu, A.; Dragoman, D.; Iftimie, S.

    2012-07-15

    We show that amphoteric refraction of ballistic electrons, i.e., positive or negative refraction depending on the incidence angle, occurs at an interface between an isotropic and an anisotropic medium and can be employed to steer and collimate electron beams. The steering angle is determined by the materials' parameters, but the degree of collimation can be tuned in a significant range by changing the energy of ballistic electrons.

  6. Bio-inspired Armor Protective Material Systems for Ballistic Shock Mitigation

    DTIC Science & Technology

    2011-01-01

    Coupon testing a b s t r a c t Severe transient ballistic shocks from projectile impacts, mine blasts , or overhead artillery attacks can incapacitate an...past two decades [1]. A ballistic shock results from a significant amount of concentrated energy deposited from caliber projectile impacts, mine blasts ...LS- Dyna , has been predominately utilized to calculate the target shock responses including acceleration histo- ries, shock response spectra

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karp, A.

    Belatedly, Western Nations are trying to staunch the flow of technology that has helped create a number of new ballistic missile forces in the Third World. Ballistic missiles already are being used in one Third World conflict. Since the end of February, Iran and Iraq have fired more than 100 short-range, inaccurate missiles at each other's cities, causing thousands of casualties. These events illustrate that ballistic missiles are becoming an ominous reality in the Third World. Indeed, 20 Third World countries, including Israel and Brazil, currently possess ballistic missiles or are striving to develop them. On one level, these missilesmore » - which are propelled by rockets into the upper atmosphere, travel in a ballistic trajectory, and are pulled by gravity to their targets - are for these nations a logical step in building up their military forces. While the missiles vary in range and accuracy, they can reach many targets in regional conflicts. Unlike manned aircraft, the do not require large, vulnerable bases. They are not as easily intercepted as slow bombers. And they are easier to develop because they are less sophisticated than modern cruise missiles such as the U.S. air-launched cruise missiles. In terms of global security, the most worrisome aspect of Third World ballistic missiles is their potential as nuclear weapons delivery systems.« less

  8. Force-induced desorption of 3-star polymers: a self-avoiding walk model

    NASA Astrophysics Data System (ADS)

    Janse van Rensburg, E. J.; Whittington, S. G.

    2018-05-01

    We consider a simple cubic lattice self-avoiding walk model of 3-star polymers adsorbed at a surface and then desorbed by pulling with an externally applied force. We determine rigorously the free energy of the model in terms of properties of a self-avoiding walk, and show that the phase diagram includes four phases, namely a ballistic phase where the extension normal to the surface is linear in the length, an adsorbed phase and a mixed phase, in addition to the free phase where the model is neither adsorbed nor ballistic. In the adsorbed phase all three branches or arms of the star are adsorbed at the surface. In the ballistic phase two arms of the star are pulled into a ballistic phase, while the remaining arm is in a free phase. In the mixed phase two arms in the star are adsorbed while the third arm is ballistic. The phase boundaries separating the ballistic and mixed phases, and the adsorbed and mixed phases, are both first order phase transitions. The presence of the mixed phase is interesting because it does not occur for pulled, adsorbed self-avoiding walks. In an atomic force microscopy experiment it would appear as an additional phase transition as a function of force.

  9. Are certain fractures at increased risk for compartment syndrome after civilian ballistic injury?

    PubMed

    Meskey, Thomas; Hardcastle, John; O'Toole, Robert V

    2011-11-01

    Compartment syndrome after ballistic fracture is uncommon but potentially devastating. Few data are available to help guide clinicians regarding risk factors for developing compartment syndrome after ballistic fractures. Our primary hypothesis was that ballistic fractures of certain bones would be at higher risk for development of compartment syndrome. A retrospective review at a Level I trauma center from 2001 through 2007 yielded 650 patients with 938 fractures resulting from gunshots. We reviewed all operative notes, clinic notes, discharge summaries, and data from our prospective trauma database. Cases in which the attending orthopedic surgeon diagnosed compartment syndrome and performed fasciotomy were considered cases with compartment syndrome. We excluded all prophylactic fasciotomies. Univariate analyses were conducted to identify risk factors associated with development of compartment syndrome. Twenty-six (2.8%) of the 938 fractures were associated with compartment syndrome. Only fibular (11.6%) and tibial (11.4%) fractures had incidence significantly higher than baseline for all ballistic fractures (p < 0.001). Fractures of the proximal third of the fibula were more likely to result in compartment syndrome than fractures of the middle or distal third (p = 0.03), as were fractures of the proximal third of the tibia (p = 0.01). No other demographic or injury parameters were associated with compartment syndrome. Ballistic fractures of the fibula and tibia are at increased risk for development of compartment syndrome over other ballistic fractures. We recommend increased vigilance when treating these injuries, particularly if the fracture is in the proximal aspect of the bone or is associated with vascular injury.

  10. Cost of space-based laser ballistic missile defense.

    PubMed

    Field, G; Spergel, D

    1986-03-21

    Orbiting platforms carrying infrared lasers have been proposed as weapons forming the first tier of a ballistic missile defense system under the President's Strategic Defense Initiative. As each laser platform can destroy a limited number of missiles, one of several methods of countering such a system is to increase the number of offensive missiles. Hence it is important to know whether the cost-exchange ratio, defined as the ratio of the cost to the defense of destroying a missile to the cost to the offense of deploying an additional missile, is greater or less than 1. Although the technology to be used in a ballistic missile defense system is still extremely uncertain, it is useful to examine methods for calculating the cost-exchange ratio. As an example, the cost of an orbiting infrared laser ballistic missile defense system employed against intercontinental ballistic missiles launched simultaneously from a small area is compared to the cost of additional offensive missiles. If one adopts lower limits to the costs for the defense and upper limits to the costs for the offense, the cost-exchange ratio comes out substantially greater than 1. If these estimates are confirmed, such a ballistic missile defense system would be unable to maintain its effectiveness at less cost than it would take to proliferate the ballistic missiles necessary to overcome it and would therefore not satisfy the President's requirements for an effective strategic defense. Although the method is illustrated by applying it to a space-based infrared laser system, it should be straightforward to apply it to other proposed systems.

  11. Cost of space-based laser ballistic missile defense

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Field, G.; Spergel, D.

    1986-03-21

    Orbiting platforms carrying infrared lasers have been proposed as weapons forming the first tier of a ballistic missile defense system under the President's Strategic Defense Initiative. As each laser platform can destroy a limited number of missiles, one of several methods of countering such a system is to increase the number of offensive missiles. Hence it is important to know whether the cost-exchange ratio, defined as the ratio of the cost to the defense of destroying a missile to the cost to the offense of deploying an additional missile, is greater or less than 1. Although the technology to bemore » used in a ballistic missile defense system is still extremely uncertain, it is useful to examine methods for calculating the cost-exchange ration. As an example, the cost of an orbiting infrared laser ballistic missile defense system employed against intercontinental ballistic missiles launched simultaneously from a small area is compared to the cost of additional offensive missiles. If one adopts lower limits to the costs for the defense and upper limits to the costs for the offense, the cost-exchange ratio comes out substantially greater than 1. If these estimates are confirmed, such a ballistic missile defense system would be unable to maintain its effectiveness at less cost than it would take to proliferate the ballistic missiles necessary to overcome it and would therefore not satisfy the President's requirements for an effective strategic defense. Although the method is illustrated by applying it to a space-based infrared laser system, it should be straightforward to apply it to other proposed systems. 28 references, 2 tables.« less

  12. Acute Effects of Static vs. Ballistic Stretching on Strength and Muscular Fatigue Between Ballet Dancers and Resistance-Trained Women.

    PubMed

    Lima, Camila D; Brown, Lee E; Wong, Megan A; Leyva, Whitney D; Pinto, Ronei S; Cadore, Eduardo L; Ruas, Cassio V

    2016-11-01

    Lima, CD, Brown, LE, Wong, MA, Leyva, WD, Pinto, RS, Cadore, EL, and Ruas, CV. Acute effects of static vs. ballistic stretching on strength and muscular fatigue between ballet dancers and resistance-trained women. J Strength Cond Res 30(11): 3220-3227, 2016-Stretching is used to increase joint range of motion, but the acute effects can decrease muscle strength. However, this may depend on the population or mode of stretching. The purpose of this study was to compare the acute effects of static vs. ballistic stretching on strength and muscular fatigue between ballet dancers and resistance-trained women. Fifteen resistance-trained women (age 23.8 ± 1.80 years, mass 67.47 ± 7.77 kg, height 168.30 ± 5.53 cm) and 12 ballet dancers (age 22.8 ± 3.04 years, mass 58.67 ± 5.65 kg, height 168.00 ± 7.69 cm) performed 5 days of testing. The first day was control (no stretching), whereas the other 4 days were static or ballistic stretching in a counterbalanced order. Range of motion, strength, and fatigue tests were also performed. Both groups demonstrated a significant decrease in hamstrings strength after static (102.71 ± 2.67 N·m) and ballistic stretching (99.49 ± 2.61 N·m) compared with control (113.059 ± 3.25 N·m), with no changes in quadriceps strength. For fatigue, only ballet dancers demonstrated a decrease from control (71.79 ± 4.88%) to ballistic (65.65 ± 8.19%), but no difference with static (65.01 ± 12.29%). These findings suggest that stretching decreases hamstrings strength similarly in ballet dancers and resistance-trained women, with no differences between modes of stretching. However, ballistic stretching only decreased muscular fatigue in ballet dancers, but not in resistance-trained women. Therefore, no stretching should be performed before strength performance. However, ballistic stretching may decrease acute muscular fatigue in ballet dancers.

  13. An Introduction to the Sources of Delivery Error for Direct-Fire Ballistic Projectiles

    DTIC Science & Technology

    2013-07-01

    Ballistic mismatch has also been used to quantify the difference in target impacts using different gun tubes ...the angle between the local “upwards” direction of the gun tube and the vertical direction as defined by gravity. Cant results from the gun tube ...Determining Optimal Tube Shape for Reduction of Jump Error for Tank Fleets Using Fleet Zero. Presented at the 20th International Symposium on Ballistics

  14. Aircraft Pilot Situational Awareness Interface for Airborne Operation of Network Controlled Unmanned Systems (US)

    DTIC Science & Technology

    2008-03-01

    operator, can be operated autonomously or remotely, can be expendable or recoverable, and can carry a lethal or nonlethal payload. Ballistic or semi ...states that vehicles should be recoverable, and that ballistic or semi - ballistic vehicles, cruise missiles, and artillery projectiles are not considered...2007-2032. 32 Nicola Tesla and his telautomatons (robots); Tesla further demonstrated remote control of objects by wireless in an exhibition in 1898

  15. Friction Stir Weld Failure Mechanisms in Aluminum-Armor Structures Under Ballistic Impact Loading Conditions

    DTIC Science & Technology

    2013-01-01

    REPORT Friction Stir Weld Failure Mechanisms in Aluminum -Armor Structures Under Ballistic Impact Loading Conditions 14. ABSTRACT 16. SECURITY...Stir Weld Failure Mechanisms in Aluminum -Armor Structures Under Ballistic Impact Loading Conditions M. Grujicic, B. Pandurangan, A. Arakere, C-F. Yen...K.O. Pedersen, Fracture Mechanisms of Aluminum Alloy AA7075-T651 Under Various Loading Conditions , Int. J. Impact Eng., 2010, 37, p 537–551 24. T

  16. Modeling and Simulation of Ballistic Penetration of Ceramic-Polymer-Metal Layered Systems

    DTIC Science & Technology

    2016-01-01

    ARL-RP-0562 ● JAN 2016 US Army Research Laboratory Modeling and Simulation of Ballistic Penetration of Ceramic-Polymer-Metal...manufacturer’s or trade names does not constitute an official endorsement or approval of the use thereof. Destroy this report when it is no longer needed...Do not return it to the originator. ARL-RP-0562 ● JAN 2016 US Army Research Laboratory Modeling and Simulation of Ballistic

  17. Ballistic damage in hybrid composite laminates

    NASA Astrophysics Data System (ADS)

    Phadnis, Vaibhav A.; Pandya, Kedar S.; Naik, Niranjan K.; Roy, Anish; Silberschmidt, Vadim V.

    2015-07-01

    Ballistic damage of hybrid woven-fabric composites made of plain-weave E-glass- fabric/epoxy and 8H satin-weave T300 carbon-fabric/epoxy is studied using a combination of experimental tests, microstructural studies and finite-element (FE) analysis. Ballistic tests were conducted with a single-stage gas gun. Fibre damage and delamination were observed to be dominating failure modes. A ply-level FE model was developed, with a fabric-reinforced ply modelled as a homogeneous orthotropic material with capacity to sustain progressive stiffness degradation due to fibre/matrix cracking, fibre breaking and plastic deformation under shear loading. Simulated damage patterns on the front and back faces of fabric-reinforced composite plates provided an insight into their damage mechanisms under ballistic loading.

  18. Analysis of entry of additional energy to gunpowder in electrothermal chemical shot

    NASA Astrophysics Data System (ADS)

    Burkin, Viktor; Ishchenko, Alexandr; Kasimov, Vladimir; Samorokova, Nina; Sidorov, Aleksey

    2017-11-01

    In the article two series of ballistic experiments conducted according to the scheme of electrothermal chemical control of ballistic parameters of the shot at the Research Institute of Applied Mathematics and Mechanics of Tomsk State University (RIAMM TSU, Russia) are considered. The experimental part of the work is described. The analysis of the electro physical data of ballistic experiments is carried out. A methodical approach that allows to take into account the entry of an electric discharge plasma in a gunpowder in the mathematical model of internal ballistic processes in barrel systems is proposed and tested. Under the conditions of these experiments, the effects of various characteristics of the plasmatron on the nature of the energy entry are estimated.

  19. Detection technique of targets for missile defense system

    NASA Astrophysics Data System (ADS)

    Guo, Hua-ling; Deng, Jia-hao; Cai, Ke-rong

    2009-11-01

    Ballistic missile defense system (BMDS) is a weapon system for intercepting enemy ballistic missiles. It includes ballistic-missile warning system, target discrimination system, anti-ballistic-missile guidance systems, and command-control communication system. Infrared imaging detection and laser imaging detection are widely used in BMDS for surveillance, target detection, target tracking, and target discrimination. Based on a comprehensive review of the application of target-detection techniques in the missile defense system, including infrared focal plane arrays (IRFPA), ground-based radar detection technology, 3-dimensional imaging laser radar with a photon counting avalanche photodiode (APD) arrays and microchip laser, this paper focuses on the infrared and laser imaging detection techniques in missile defense system, as well as the trends for their future development.

  20. Higher-than-ballistic conduction of viscous electron flows

    PubMed Central

    Guo, Haoyu; Ilseven, Ekin; Falkovich, Gregory; Levitov, Leonid S.

    2017-01-01

    Strongly interacting electrons can move in a neatly coordinated way, reminiscent of the movement of viscous fluids. Here, we show that in viscous flows, interactions facilitate transport, allowing conductance to exceed the fundamental Landauer’s ballistic limit Gball. The effect is particularly striking for the flow through a viscous point contact, a constriction exhibiting the quantum mechanical ballistic transport at T=0 but governed by electron hydrodynamics at elevated temperatures. We develop a theory of the ballistic-to-viscous crossover using an approach based on quasi-hydrodynamic variables. Conductance is found to obey an additive relation G=Gball+Gvis, where the viscous contribution Gvis dominates over Gball in the hydrodynamic limit. The superballistic, low-dissipation transport is a generic feature of viscous electronics. PMID:28265079

  1. Using the spatial distribution and lithology of ballistic blocks to interpret eruption sequence and dynamics: August 6 2012 Upper Te Maari eruption, New Zealand

    NASA Astrophysics Data System (ADS)

    Breard, E. C. P.; Lube, G.; Cronin, S. J.; Fitzgerald, R.; Kennedy, B.; Scheu, B.; Montanaro, C.; White, J. D. L.; Tost, M.; Procter, J. N.; Moebis, A.

    2014-10-01

    The ballistic ejection of blocks during explosive eruptions constitutes a major hazard near active volcanoes. Fields of ballistic clasts can provide important clues towards quantifying the energy, dynamics and directionality of explosive events, but detailed datasets are rare. During the 6 August 2012 hydrothermal eruption of Upper Te Maari (Tongariro), New Zealand, three explosions occurred in rapid succession within less than 20 s. The first two produced laterally-directed pyroclastic density currents (PDC), and the final vertical explosion generated an ash plume. Each of these explosions was associated with the ejection of ballistic blocks. We present detailed maps of the resulting 5.1 km2 block impact field and the distribution of the > 2200 impact craters with diameters > 2.5 m. There are two distinct regions of high crater concentration, where crater densities reach more than six times the average background density. These occur at distances of 500-700 m east and 1000-1350 west of a 430-m-long fissure that was created during the eruption. The high-density fields are characterized by a narrow radial spread of < 45° and are located along the proximal transport direction of the pyroclastic density currents. A provenance analysis of ballistic blocks allowed us to reconstruct two different eruptive vents for the explosions. The first two laterally-directed explosions were sourced from the fissure, while the third explosion occurred through the pre-existing Upper Te Maari Crater, generating a roughly axisymmetric shower of ballistics. Stratigraphic relationships between impact craters, PDC and fall deposits suggest that the ballistic blocks were initially coupled with the rapidly expanding gas-particle mixtures that produced the PDCs. Ballistic trajectory modeling, reproducing the lateral extent and main impact density pattern of the western impact field, allows estimation of the vertical expansion angle of the second and largest explosion. The calculations show that the largest proportion of the explosion energy was strongly focused as a narrow and extremely shallow (from - 3 to 15° from the horizontal) laterally expanding hydrothermal blast. The results presented here constitute an important data set for ballistic hazard assessment at Tongariro volcano and they can provide further clues towards better understanding highly energetic laterally directed volcanic explosions at similar hydrothermal fields.

  2. Ballistic movements of jumping legs implemented as variable components of cricket behaviour.

    PubMed

    Hustert, R; Baldus, M

    2010-12-01

    Ballistic accelerations of a limb or the whole body require special joint mechanisms in many animals. Specialized joints can be moved by stereotypic or variable motor control during motor patterns with and without ballistic components. As a model of variable motor control, the specialized femur-tibia (knee) joints of cricket (Acheta domesticus) hindlegs were studied during ballistic kicking, jumping and swimming and in non-ballistic walking. In this joint the tendons of the antagonistic flexor and the extensor muscles attach at different distances from the pivot and the opposed lever arms form an angle of 120 deg. A 10:1 ratio of their effective lever arms at full knee flexion helps to prepare for most ballistic extensions: the tension of the extensor can reach its peak while it is restrained by flexor co-contraction. In kicks, preparatory flexion is rapid and the co-contraction terminates just before knee extensions. Therefore, mainly the stored tension of the extensor muscle accelerates the small mass of the tibia. Jumps are prepared with slower extensor-flexor co-contractions that flex both knees simultaneously and then halt to rotate both legs outward to a near horizontal level. From there, catapult extension of both knees accelerates the body, supported by continued high frequency motor activity to their tibia extensor muscles during the ongoing push-off from the substrate. Premature extension of one knee instantly takes load from the lagging leg that extends and catches up, which finally results in a straight jump. In swimming, synchronous ballistic power strokes of both hindlegs drive the tibiae on a ventral-to-posterior trajectory through the water, well coordinated with the swimming patterns of all legs. In walking, running and climbing the steps of the hindlegs range between 45 deg flexion and 125 deg extension and use non-ballistic, alternating activity of knee flexor and extensor muscles. Steep climbing requires longer bursts from the extensor tibiae muscles when they support the extended hindlegs against gravity forces when the body hangs over. All ballistic movements of cricket knees are elicited by a basic but variable motor pattern: knee flexions by co-contraction of the antagonists prepare catapult extensions with speeds and forces as required in the different behaviours.

  3. Dual-hemisphere transcranial direct current stimulation over primary motor cortex enhances consolidation of a ballistic thumb movement.

    PubMed

    Koyama, Soichiro; Tanaka, Satoshi; Tanabe, Shigeo; Sadato, Norihiro

    2015-02-19

    Transcranial direct current stimulation (tDCS) is a noninvasive technique that modulates motor performance and learning. Previous studies have shown that tDCS over the primary motor cortex (M1) can facilitate consolidation of various motor skills. However, the effect of tDCS on consolidation of newly learned ballistic movements remains unknown. The present study tested the hypothesis that tDCS over M1 enhances consolidation of ballistic thumb movements in healthy adults. Twenty-eight healthy subjects participated in an experiment with a single-blind, sham-controlled, between-group design. Fourteen subjects practiced a ballistic movement with their left thumb during dual-hemisphere tDCS. Subjects received 1mA anodal tDCS over the contralateral M1 and 1mA cathodal tDCS over the ipsilateral M1 for 25min during the training session. The remaining 14 subjects underwent identical training sessions, except that dual-hemisphere tDCS was applied for only the first 15s (sham group). All subjects performed the task again at 1h and 24h later. Primary measurements examined improvement in peak acceleration of the ballistic thumb movement at 1h and 24h after stimulation. Improved peak acceleration was significantly greater in the tDCS group (144.2±15.1%) than in the sham group (98.7±9.1%) (P<0.05) at 24h, but not 1h, after stimulation. Thus, dual-hemisphere tDCS over M1 enhanced consolidation of ballistic thumb movement in healthy adults. Dual-hemisphere tDCS over M1 may be useful to improve elemental motor behaviors, such as ballistic movements, in patients with subcortical strokes. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  4. Hazard map for volcanic ballistic impacts at Popocatépetl volcano (Mexico)

    NASA Astrophysics Data System (ADS)

    Alatorre-Ibargüengoitia, Miguel A.; Delgado-Granados, Hugo; Dingwell, Donald B.

    2012-11-01

    During volcanic explosions, volcanic ballistic projectiles (VBP) are frequently ejected. These projectiles represent a threat to people, infrastructure, vegetation, and aircraft due to their high temperatures and impact velocities. In order to protect people adequately, it is necessary to delimit the projectiles' maximum range within well-defined explosion scenarios likely to occur in a particular volcano. In this study, a general methodology to delimit the hazard zones for VBP during volcanic eruptions is applied to Popocatépetl volcano. Three explosion scenarios with different intensities have been defined based on the past activity of the volcano and parameterized by considering the maximum kinetic energy associated with VBP ejected during previous eruptions. A ballistic model is used to reconstruct the "launching" kinetic energy of VBP observed in the field. In the case of Vulcanian eruptions, the most common type of activity at Popocatépetl, the ballistic model was used in concert with an eruptive model to correlate ballistic range with initial pressure and gas content, parameters that can be estimated by monitoring techniques. The results are validated with field data and video observations of different Vulcanian eruptions at Popocatépetl. For each scenario, the ballistic model is used to calculate the maximum range of VBP under optimum "launching" conditions: ballistic diameter, ejection angle, topography, and wind velocity. Our results are presented in the form of a VBP hazard map with topographic profiles that depict the likely maximum ranges of VBP under explosion scenarios defined specifically for Popocatépetl volcano. The hazard zones shown on the map allow the responsible authorities to plan the definition and mitigation of restricted areas during volcanic crises.

  5. A Simple Ballistic Material Model for Soda-Lime Glass

    DTIC Science & Technology

    2009-01-01

    Author’s personal copy A simple ballistic material model for soda-lime glass M. Grujicic a,*, B. Pandurangan a, N. Coutris a, B.A. Cheeseman b, C...Transparent armor Material modeling Ballistic performance Soda-lime glass a b s t r a c t Various open-literature experimental findings pertaining...notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not

  6. Precession feature extraction of ballistic missile warhead with high velocity

    NASA Astrophysics Data System (ADS)

    Sun, Huixia

    2018-04-01

    This paper establishes the precession model of ballistic missile warhead, and derives the formulas of micro-Doppler frequency induced by the target with precession. In order to obtain micro-Doppler feature of ballistic missile warhead with precession, micro-Doppler bandwidth estimation algorithm, which avoids velocity compensation, is presented based on high-resolution time-frequency transform. The results of computer simulations confirm the effectiveness of the proposed method even with low signal-to-noise ratio.

  7. Terminal Performance of Lead Free Pistol Bullets in Ballistic Gelatin Using Retarding Force Analysis from High Speed Video

    DTIC Science & Technology

    2016-04-04

    Terminal Performance of Lead-Free Pistol Bullets in Ballistic Gelatin Using Retarding Force Analysis from High Speed Video ELIJAH COURTNEY, AMY...quantified using high speed video . The temporary stretch cavities and permanent wound cavities are also characterized. Two factors tend to re- duce the...Performance of Lead-Free Pistol Bullets in Ballistic Gelatin Using Retarding Force Analysis from High Speed Video cavity. In addition, stretching can also

  8. Navy Ohio Replacement (SSBN[X]) Ballistic Missile Submarine Program: Background and Issues for Congress

    DTIC Science & Technology

    2016-04-05

    Navy Ohio Replacement (SSBN[ X ]) Ballistic Missile Submarine Program: Background and Issues for Congress Ronald O’Rourke Specialist in Naval...Affairs April 5, 2016 Congressional Research Service 7-5700 www.crs.gov R41129 Navy Ohio Replacement (SSBN[ X ]) Ballistic Missile Submarine...as the SSBN( X ) program, as the Navy’s top priority program. The Navy wants to procure the first Ohio replacement boat in FY2021, and the $773.1

  9. Self-Attractive Random Walks: The Case of Critical Drifts

    NASA Astrophysics Data System (ADS)

    Ioffe, Dmitry; Velenik, Yvan

    2012-07-01

    Self-attractive random walks (polymers) undergo a phase transition in terms of the applied drift (force): If the drift is strong enough, then the walk is ballistic, whereas in the case of small drifts self-attraction wins and the walk is sub-ballistic. We show that, in any dimension d ≥ 2, this transition is of first order. In fact, we prove that the walk is already ballistic at critical drifts, and establish the corresponding LLN and CLT.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, Barton; Rajic, Slobodan; Hunter, Scott Robert

    The objective of this work was to demonstrate that a superhydrophobic coating technology developed at Oak Ridge National Laboratory (ORNL) increases the water repellency of ballistic fabric beyond that provided by existing water repellency treatments. This increased water repellency has the potential to provide durable ballistic fabric for body armor without adding significant weight to the armor or significant manufacturing cost. Specimens of greige and scoured ballistic fabric were treated with a superhydrophobic coating and their weights and degree of water repellency were compared to specimens of untreated fabric. Treatment of both greige and scoured ballistic fabrics yielded highly watermore » repellent fabrics. Our measurements of the water droplet contact angles gave values of approximately 150 , near the lower limit of 160 for superhydrophobic surfaces. The coatings increased the fabric weights by approximately 6%, an amount that is many times less than the estimated weight increase in a conventional treatment of ballistic fabric. The treated fabrics retained a significant amount of water repellency following a basic abrasion test, with water droplet contact angles decreasing by 14 to 23 . Microscopic analysis of the coating applied to woven fabrics indicated that the coating adhered equally well to fibers of greige and scoured yarns. Future evaluation of the superhydrophobic water repellent treatment will involve the manufacture of shoot packs of treated fabric for ballistic testing and provide an analysis of manufacturing scale-up and cost-to-benefit considerations.« less

  11. Ballistic heat conduction and mass disorder in one dimension.

    PubMed

    Ong, Zhun-Yong; Zhang, Gang

    2014-08-20

    It is well-known that in the disordered harmonic chain, heat conduction is subballistic and the thermal conductivity (κ) scales asymptotically as lim(L--> ∞) κ ∝ L(0.5) where L is the chain length. However, using the nonequilibrium Green's function (NEGF) method and analytical modelling, we show that there exists a critical crossover length scale (LC) below which ballistic heat conduction (κ ∝ L) can coexist with mass disorder. This ballistic-to-subballistic heat conduction crossover is connected to the exponential attenuation of the phonon transmittance function Ξ i.e. Ξ(ω, L) = exp[-L/λ(ω)], where λ is the frequency-dependent attenuation length. The crossover length can be determined from the minimum attenuation length, which depends on the maximum transmitted frequency. We numerically determine the dependence of the transmittance on frequency and mass composition as well as derive a closed form estimate, which agrees closely with the numerical results. For the length-dependent thermal conductance, we also derive a closed form expression which agrees closely with numerical results and reproduces the ballistic to subballistic thermal conduction crossover. This allows us to characterize the crossover in terms of changes in the length, mass composition and temperature dependence, and also to determine the conditions under which heat conduction enters the ballistic regime. We describe how the mass composition can be modified to increase ballistic heat conduction.

  12. Higher-Than-Ballistic Conduction in Viscous Electron Fluids

    NASA Astrophysics Data System (ADS)

    Levitov, Leonid

    Strongly interacting electrons can move in a neatly coordinated way, reminiscent of the movement of viscous fluids. This talk will argue that in viscous flows interactions facilitate transport, allowing conductance to exceed the fundamental Sharvin-Landauer quantum-ballistic limit. The effect is particularly striking for the flow through a viscous point contact, a constriction exhibiting the quantum-mechanical ballistic transport at T = 0 but governed by electron hydrodynamics at elevated temperatures. Conductance grows as a square of the constriction width, i.e. faster than the linear width dependence for noninteracting fermions. The crossover between the ballistic and viscous regimes occurs when the mean free path for e-e collisions becomes comparable to the constriction width. Further, we will discuss the negative nonlocal response, a signature effect of viscous transport. This response exhibits an interesting nonmonotonic behavior vs. T at the viscous-to-balistic transition. The response is negative but small in the highly viscous regime at elevated temperatures. The value grows as the temperature is lowered and the system becomes less viscous, reaching the most negative values in the crossover region where the mean free path is comparable to the distance between contacts. Subsequently, it reverses sign at even lower temperatures, becoming positive as the system enters the ballistic regime. This peculiar behavior provides a clear signature of the ballistic-to-viscous transition and enables a direct measurement of the electron-electron collision mean free path.

  13. From Snowballs to ICBM's.

    ERIC Educational Resources Information Center

    Scherr, Charles W.

    1979-01-01

    Shows that the elementary ballistic range problem solution, when scaled by the reciprocal of the eccentricity, contains in itself a good description of the more general Keplerian ballistic problem. (Author/GA)

  14. Effect of the Lateral Exospheric Transport on the Horizontal Hydrogen Distribution Near the Exobase of Mars

    NASA Astrophysics Data System (ADS)

    Chaufray, J.-Y.; Yelle, R. V.; Gonzalez-Galindo, F.; Forget, F.; Lopez-Valverde, M.; Leblanc, F.; Modolo, R.

    2018-03-01

    We simulate the hydrogen density near the exobase of Mars, using the 3-D Martian Global Circulation Model of Laboratoire de Météorologie Dynamique, coupled to an exospheric ballistic model to compute the downward ballistic flux. The simulated hydrogen distribution near the exobase obtained at two different seasons—Ls = 180° and Ls = 270°—is close to Zero Net Ballistic Flux equilibrium. In other words, the hydrogen density near the exobase adjusts to have a balance between the local upward ballistic and the downward ballistic flux due to a short lateral migration time in the exosphere compared to the vertical diffusion time. This equilibrium leads to a hydrogen density n near the exobase directly controlled by the exospheric temperature T by the relation nT5/2 = constant. This relation could be used to extend 1-D hydrogen exospheric model of Mars used to derive the hydrogen density and escape flux at Mars from Lyman-α observations to 3-D model based on observed or modeled exospheric temperature near the exobase, without increasing the number of free parameters.

  15. Direct measurement of the ballistic motion of a freely floating colloid in Newtonian and viscoelastic fluids.

    PubMed

    Hammond, Andrew P; Corwin, Eric I

    2017-10-01

    A thermal colloid suspended in a liquid will transition from a short-time ballistic motion to a long-time diffusive motion. However, the transition between ballistic and diffusive motion is highly dependent on the properties and structure of the particular liquid. We directly observe a free floating tracer particle's ballistic motion and its transition to the long-time regime in both a Newtonian fluid and a viscoelastic Maxwell fluid. We examine the motion of the free particle in a Newtonian fluid and demonstrate a high degree of agreement with the accepted Clercx-Schram model for motion in a dense fluid. Measurements of the functional form of the ballistic-to-diffusive transition provide direct measurements of the temperature, viscosity, and tracer radius. We likewise measure the motion in a viscoelastic Maxwell fluid and find a significant disagreement between the theoretical asymptotic behavior and our measured values of the microscopic properties of the fluid. We observe a greatly increased effective mass for a freely moving particle and a decreased plateau modulus.

  16. Comparison of the ballistic contractile responses generated during microstimulation of single human motor axons with brief irregular and regular stimuli.

    PubMed

    Leitch, Michael; Macefield, Vaughan G

    2017-08-01

    Ballistic contractions are induced by brief, high-frequency (60-100 Hz) trains of action potentials in motor axons. During ramp voluntary contractions, human motoneurons exhibit significant discharge variability of ∼20% and have been shown to be advantageous to the neuromuscular system. We hypothesized that ballistic contractions incorporating discharge variability would generate greater isometric forces than regular trains with zero variability. High-impedance tungsten microelectrodes were inserted into human fibular nerve, and single motor axons were stimulated with both irregular and constant-frequency stimuli at mean frequencies ranging from 57.8 to 68.9 Hz. Irregular trains generated significantly greater isometric peak forces than regular trains over identical mean frequencies. The high forces generated by ballistic contractions are not based solely on high frequencies, but rather a combination of high firing rates and discharge irregularity. It appears that irregular ballistic trains take advantage of the "catchlike property" of muscle, allowing augmentation of force. Muscle Nerve 56: 292-297, 2017. © 2016 Wiley Periodicals, Inc.

  17. Immunologic responses of bison to vaccination with Brucella abortus strain RB51: comparison of parenteral to ballistic delivery via compressed pellets or photopolymerized hydrogels.

    PubMed

    Olsen, Steven C; Christie, R J; Grainger, D W; Stoffregen, W S

    2006-02-27

    This study compared responses of bison calves to 10(10)CFU of Brucella abortus strain RB51 (SRB51) delivered by parenteral or ballistic methods. Two types of biobullet payloads were evaluated; compacted SRB51 pellets or SRB51 encapsulated in photopolymerized poly(ethylene glycol) hydrogels. Bison were vaccinated with saline, parenteral SRB51 alone, or in combination with Spirovac, or ballistically with compressed SRB51 or hydrogel biobullets. Bison parenterally vaccinated with SRB51 had greater (P<0.05) immunologic responses when compared to control bison. Co-administration of Spirovac as an adjuvant did not influence immunologic responses. As compared to compressed SRB51 biobullets, ballistic vaccination with hydrogel biobullets increased cellular immune responses at some sampling times. Our data suggest that hydrogel formulations of SRB51 may be a superior alternative to compressed SRB51 tablets for ballistic vaccination of bison. Although preliminary, data suggests that immunologic responses of bison to SRB51 hydrogel bullets are similar to responses after parenteral vaccination with SRB51.

  18. The National Ballistics Imaging Comparison (NBIC) project.

    PubMed

    Song, J; Vorburger, T V; Ballou, S; Thompson, R M; Yen, J; Renegar, T B; Zheng, A; Silver, R M; Ols, M

    2012-03-10

    In response to the guidelines issued by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB-International) to establish traceability and quality assurance in U.S. crime laboratories, a NIST/ATF joint project entitled National Ballistics Imaging Comparison (NBIC) was initialized in 2008. The NBIC project aims to establish a National Traceability and Quality System for ballistics identifications in crime laboratories within the National Integrated Ballistics Information Network (NIBIN) of the U.S. NIST Standard Reference Material (SRM) 2460 bullets and 2461 cartridge cases are used as reference standards. 19 ballistics examiners from 13 U.S. crime laboratories participated in this project. They each performed 24 periodic image acquisitions and correlations of the SRM bullets and cartridge cases over the course of a year, but one examiner only participated in Phase 1 tests of SRM cartridge case. The correlation scores were collected by NIST for statistical analyses, from which control charts and control limits were developed for the proposed Quality System and for promoting future assessments and accreditations for firearm evidence in U.S. forensic laboratories in accordance with the ISO 17025 Standard. Published by Elsevier Ireland Ltd.

  19. Concept and numerical simulations of a reactive anti-fragment armour layer

    NASA Astrophysics Data System (ADS)

    Hušek, Martin; Kala, Jiří; Král, Petr; Hokeš, Filip

    2017-07-01

    The contribution describes the concept and numerical simulation of a ballistic protective layer which is able to actively resist projectiles or smaller colliding fragments flying at high speed. The principle of the layer was designed on the basis of the action/reaction system of reactive armour which is used for the protection of armoured vehicles. As the designed ballistic layer consists of steel plates simultaneously combined with explosive material - primary explosive and secondary explosive - the technique of coupling the Finite Element Method with Smoothed Particle Hydrodynamics was used for the simulations. Certain standard situations which the ballistic layer should resist were simulated. The contribution describes the principles for the successful execution of numerical simulations, their results, and an evaluation of the functionality of the ballistic layer.

  20. Novel formulations of ballistic gelatin. 1. Rheological properties.

    PubMed

    Zecheru, Teodora; Său, Ciprian; Lăzăroaie, Claudiu; Zaharia, Cătălin; Rotariu, Traian; Stănescu, Paul-Octavian

    2016-06-01

    Ballistic gelatin is the simulant of the human body during field tests in forensics and other related fields, due to its physical and mechanical similarities to human trunk and organs. Since the ballistic gelatin used in present has important issues to overcome, an alternative approach is the use of gelatin-polymer composites, where a key factor is the insertion of biocompatible materials, which replicate accurately the human tissues. In order to be able to obtain an improved material in terms of mechanical performances by an easy industrial-scale technology, before the verification of the ballistic parameters by shooting in agreement with military standards, one of the best and cheapest solutions is to perform a thorough check of their rheological properties, in standard conditions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nagler, R.G.

    This report, based solely on information available from unclassified sources, provides a coherent picture of the scope and trends of ballistic missile proliferation. The focus is on countries developing, producing, or owning ballistic missiles capable of threatening the military forces, assets, or populations of neighboring or geographically remote countries. The report also identifies other countries expected to obtain operational ballistic missile capabilities, discusses expected growth in performance, and examines the projected availability of warheads of mass destruction. The emphasis is on ballistic missiles of ranges greater than approximately 300 km, though shorter range battlefield weapons are discussed as forerunners. Themore » assessment excludes principal U.S. allies and countries formerly in the Warsaw Pact, except where these countries have sold missiles, technology; or personnel services to developing nations in support of their missile programs.« less

  2. Solid rocket booster performance evaluation model. Volume 3: Sample case. [propellant combustion simulation/internal ballistics

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The solid rocket booster performance evaluation model (SRB-11) is used to predict internal ballistics in a sample motor. This motor contains a five segmented grain. The first segment has a 14 pointed star configuration with a web which wraps partially around the forward dome. The other segments are circular in cross-section and are tapered along the interior burning surface. Two of the segments are inhibited on the forward face. The nozzle is not assumed to be submerged. The performance prediction is broken into two simulation parts: the delivered end item specific impulse and the propellant properties which are required as inputs for the internal ballistics module are determined; and the internal ballistics for the entire burn duration of the motor are simulated.

  3. Higher-than-ballistic conduction of viscous electron flows.

    PubMed

    Guo, Haoyu; Ilseven, Ekin; Falkovich, Gregory; Levitov, Leonid S

    2017-03-21

    Strongly interacting electrons can move in a neatly coordinated way, reminiscent of the movement of viscous fluids. Here, we show that in viscous flows, interactions facilitate transport, allowing conductance to exceed the fundamental Landauer's ballistic limit [Formula: see text] The effect is particularly striking for the flow through a viscous point contact, a constriction exhibiting the quantum mechanical ballistic transport at [Formula: see text] but governed by electron hydrodynamics at elevated temperatures. We develop a theory of the ballistic-to-viscous crossover using an approach based on quasi-hydrodynamic variables. Conductance is found to obey an additive relation [Formula: see text], where the viscous contribution [Formula: see text] dominates over [Formula: see text] in the hydrodynamic limit. The superballistic, low-dissipation transport is a generic feature of viscous electronics.

  4. Tissue characterization with ballistic photons: counting scattering and/or absorption centres

    NASA Astrophysics Data System (ADS)

    Corral, F.; Strojnik, M.; Paez, G.

    2015-03-01

    We describe a new method to separate ballistic from the scattered photons for optical tissue characterization. It is based on the hypothesis that the scattered photons acquire a phase delay. The photons passing through the sample without scattering or absorption preserve their coherence so they may participate in interference. We implement a Mach-Zehnder experimental setup where the ballistic photons pass through the sample with the delay caused uniquely by the sample indices of refraction. We incorporate a movable mirror on the piezoelectric actuator in the sample arm to detect the amplitude of the modulation term. We present the theory that predicts the path-integrated (or total) concentration of the scattering and absorption centres. The proposed technique may characterize samples with transmission attenuation of ballistic photons by a factor of 10-14.

  5. Reassessing the Representative Heuristic of the Plywood Ballistic Mannequin Used in Live-Fire Testing

    DTIC Science & Technology

    2015-04-01

    currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) April 2015 2. REPORT TYPE Final 3...the materials of construction of the current plywood ballistic mannequin (or manikin) should be more closely controlled and 2) to revise the US Army...Inappropriate 33 Appendix B. The American Plywood Association (APA) Wood Species Grouping 37 Appendix C. US Army Ballistic Research Laboratory (BRL) Plywood

  6. Fiber-Level Modeling of Dynamic Strength of Kevlar (registered trademark) KM2 Ballistic Fabric

    DTIC Science & Technology

    2012-07-01

    Ballistic-Performance Optimization of a Hybrid Carbon - Nanotube /E-glass Reinforced Poly-Vinyl-Ester-Epoxy-Matrix Com- posite Armor, J. Mater. Sci...2007, 42, p 5347–5359 4. M. Grujicic, W.C. Bell, L.L. Thompson, K.L. Koudela, and B.A. Cheeseman, Ballistic-Protection Performance of Carbon - Nanotube ...Armor via the Use of a Carbon - Nanotube Forest-Mat Strike Face, Mater. Des. Appl., 2008, 222, p 15–28 6. Y. Wang and X. Sun, Determining the Geometry

  7. Ballistic Analysis of Firing Table Data for 155MM, M825 Smoke Projectile

    DTIC Science & Technology

    1990-09-01

    PROVING GROUND , MARYLAND I I 4 .i. NOTICES Destroy this report when it is no longer needed. DO NOT return it to the originator. Additional copies of this...ADDRESS(ES) 10. SPONSORING MONITORING U.S. Army Ballistic Research Laboratory AGENCY REPORT NUMBER ATTN: SLCBR-DD-T BRL-R-3865 Aberdeen Proving Ground ...thru September 1988 at Dugway Proving Ground . Such an analysis will consider whether the M825 MOD PIP Base projectile is ballistically matched or

  8. Material Modeling and Ballistic-Resistance Analysis of Armor-Grade Composites Reinforced with High-Performance Fibers

    DTIC Science & Technology

    2009-12-01

    CLASSIFICATION OF: A new ballistic material model for 0/90 cross-plied oriented ultra-high molecular weight (UHMW) polyethylene fiber-based armor...recently developed unit cell-based ballistic material model for the same class of composites (M. Grujicic, G. Arakere, T. 1. REPORT DATE (DD-MM-YYYY) 4...ABSTRACT UU c. THIS PAGE UU 2. REPORT TYPE New Reprint 17. LIMITATION OF ABSTRACT UU 15. NUMBER OF PAGES 5d. PROJECT NUMBER 5e. TASK NUMBER 5f

  9. Ballistic missile defense effectiveness

    NASA Astrophysics Data System (ADS)

    Lewis, George N.

    2017-11-01

    The potential effectiveness of ballistic missile defenses today remains a subject of debate. After a brief discussion of terminal and boost phase defenses, this chapter will focus on long-range midcourse defenses. The problems posed by potential countermeasures to such midcourse defenses are discussed as are the sensor capabilities a defense might have available to attempt to discriminate the actual missile warhead in a countermeasures environment. The role of flight testing in assessing ballistic missile defense effectiveness is discussed. Arguments made about effectiveness by missile defense supporters and critics are summarized.

  10. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of MIL A46100 Armor-Grade Steel: A Computational Investigation

    DTIC Science & Technology

    2014-06-12

    distribution is unlimited. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel : A Computational Investigation The views...Welds of Mil A46100 Armor-Grade Steel : A Computational Investigation Report Title In our recent work, a multi-physics computational model for the...introduction of the sixth module in the present work in recognition of the fact that in thick steel GMAW weldments, the overall ballistic performance

  11. Ballistics: a primer for the surgeon.

    PubMed

    Volgas, David A; Stannard, James P; Alonso, Jorge E

    2005-03-01

    The purpose of this paper is to review the literature on ballistics and to sort through the plethora of myth and popular opinion. The trauma surgeon is increasingly faced with gunshot wounds. Knowledge of ballistics is important to help in assessing the patterns of wounds that are seen. There are many factors that affect the flight of a bullet to its target. Many of these factors also affect the behaviour of the bullet after it strikes the target. It is primarily these factors that interest the surgeon.

  12. Ballistic intercept missions to Comet Encke

    NASA Technical Reports Server (NTRS)

    Mumma, M. (Compiler)

    1975-01-01

    The optimum ballistic intercept of a spacecraft with the comet Encke is determined. The following factors are considered in the analysis: energy requirements, encounter conditions, targeting error, comet activity, spacecraft engineering requirements and restraints, communications, and scientific return of the mission. A baseline model is formulated which includes the basic elements necessary to estimate the scientific return for the different missions considered. Tradeoffs which have major impact on the cost and/or scientific return of a ballistic mission to comet Encke are identified and discussed. Recommendations are included.

  13. Directed Energy Technology Working Group Report (IDA/OSD R&M (Institute for Defense Analyses/Office of the Secretary of Defense Reliability and Maintainability) Study).

    DTIC Science & Technology

    1983-08-01

    Missile (SLBM) Defense Scenario ............................................ B-1 C Space-Based Anti-Ballistic Missile ( ABM ) Defense Scenario...Ballistic Missile (SLBM) Defense Scenario, and at Strategic Space-Based Anti-Ballistic Missile ( ABM ) Defense Scenario. These case studies are provided...of flight. 3.5.3 Spaced-Based ABM Defense Scenario In this scenario, an orbiting battle station is operating as an element of GBMD System, and it is

  14. Geometrical optimization of a local ballistic magnetic sensor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kanda, Yuhsuke; Hara, Masahiro; Nomura, Tatsuya

    2014-04-07

    We have developed a highly sensitive local magnetic sensor by using a ballistic transport property in a two-dimensional conductor. A semiclassical simulation reveals that the sensitivity increases when the geometry of the sensor and the spatial distribution of the local field are optimized. We have also experimentally demonstrated a clear observation of a magnetization process in a permalloy dot whose size is much smaller than the size of an optimized ballistic magnetic sensor fabricated from a GaAs/AlGaAs two-dimensional electron gas.

  15. Relationship between traditional and ballistic squat exercise with vertical jumping and maximal sprinting.

    PubMed

    Requena, Bernardo; García, Inmaculada; Requena, Francisco; de Villarreal, Eduardo Sáez-Sáez; Cronin, John B

    2011-08-01

    The purpose of this study was to quantify the magnitude of the relationship between vertical jumping and maximal sprinting at different distances with performance in the traditional and ballistic concentric squat exercise in well-trained sprinters. Twenty-one men performed 2 types of barbell squats (ballistic and traditional) across different loads with the aim of determining the maximal peak and average power outputs and 1 repetition maximum (1RM) values. Moreover, vertical jumping (countermovement jump test [CMJ]) and maximal sprints over 10, 20, 30, 40, 60, and 80 m were also assessed. In respect to 1RM in traditional squat, (a) no significant correlation was found with CMJ performance; (b) positive strong relationships (p < 0.01) were obtained with all the power measures obtained during both ballistic and traditional squat exercises (r = 0.53-0.90); (c) negative significant correlations (r = -0.49 to -0.59, p < 0.05) were found with sprint times in all the sprint distances measured when squat strength was expressed as a relative value; however, in the absolute mode, no significant relationships were observed with 10- and 20-m sprint times. No significant relationship was found between 10-m sprint time and relative or absolute power outputs using either ballistic or traditional squat exercises. Sprint time at 20 m was only related to ballistic and traditional squat performance when power values were expressed in relative terms. Moderate significant correlations (r = -0.39 to -0.56, p < 0.05) were observed between sprint times at 30 and 40 m and the absolute/relative power measures attained in both ballistic and traditional squat exercises. Sprint times at 60 and 80 m were mainly related to ballistic squat power outputs. Although correlations can only give insights into associations and not into cause and effect, from this investigation, it can be seen that traditional squat strength has little in common with CMJ performance and that relative 1RM and power outputs for both squat exercises are statistically correlated to most sprint distances underlying the importance of strength and power to sprinting.

  16. MRI issues for ballistic objects: information obtained at 1.5-, 3- and 7-Tesla.

    PubMed

    Dedini, Russell D; Karacozoff, Alexandra M; Shellock, Frank G; Xu, Duan; McClellan, R Trigg; Pekmezci, Murat

    2013-07-01

    Few studies exist for magnetic resonance imaging (MRI) issues and ballistics, and there are no studies addressing movement, heating, and artifacts associated with ballistics at 3-tesla (T). Movement because of magnetic field interactions and radiofrequency (RF)-induced heating of retained bullets may injure nearby critical structures. Artifacts may also interfere with the diagnostic use of MRI. To investigate these potential hazards of MRI on a sample of bullets and shotgun pellets. Laboratory investigation, ex vivo. Thirty-two different bullets and seven different shotgun pellets, commonly encountered in criminal trauma, were assessed relative to 1.5-, 3-, and 7-T magnetic resonance systems. Magnetic field interactions, including translational attraction and torque, were measured. A representative sample of five bullets were then tested for magnetic field interactions, RF-induced heating, and the generation of artifacts at 3-T. At all static magnetic field strengths, non-steel-containing bullets and pellets exhibited no movement, whereas one steel core bullet and two steel pellets exhibited movement in excess of what might be considered safe for patients in MRI at 1.5-, 3- and 7-Tesla. At 3-T, the maximum temperature increase of five bullets tested was 1.7°C versus background heating of 1.5°C. Of five bullets tested for artifacts, those without a steel core exhibited small signal voids, whereas a single steel core bullet exhibited a very large signal void. Ballistics made of lead with copper or alloy jackets appear to be safe with respect to MRI-related movement at 1.5-, 3-, and 7-T static magnetic fields, whereas ballistics containing steel may pose a danger if near critical body structures because of strong magnetic field interactions. Temperature increases of selected ballistics during 3-T MRI was not clinically significant, even for the ferromagnetic projectiles. Finally, ballistics containing steel generated larger artifacts when compared with ballistics made of lead with copper and alloy jackets and may impair the diagnostic use of MRI. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. 48 CFR 225.7016-4 - Solicitation provision.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Prohibition of Certain Contracts With Foreign Entities for the Conduct of Ballistic Missile Defense Research... Ballistic Missile Defense Program. [68 FR 15627, Mar. 31, 2003. Redesignated at 74 FR 53413, Oct. 19, 2009] ...

  18. Ballistic Missile Defense: National Security and the High Frontier of Space.

    ERIC Educational Resources Information Center

    Adragna, Steven P.

    1985-01-01

    Ballistic missile defense is discussed, and the rationale behind the proposal to place defensive weapons in space is examined. Strategic defense is a national security, political, and moral imperative. (RM)

  19. Ergonomics assessment of composite ballistic inserts for bullet- and fragment-proof vests.

    PubMed

    Majchrzycka, Katarzyna; Brochocka, Agnieszka; Luczak, Anna; Lężak, Krzysztof

    2013-01-01

    Personal protective equipment worn by uniformed services (e.g., the police and the military) must ensure protection against bodily injuries. However, a high degree of protection is always associated with significant discomfort. This article presents the results of an assessment of the ergonomics parameters of new special purpose products, ballistic inserts with improved ballistic resistance, and an assessment of the impact of the burden related to their use on the psychomotor performance of the subjects. An obstacle course and subjective ergonomics assessment questionnaires were used in tests. Thermal discomfort was also assessed. Psychological testing included tests enabling an assessment of the subjects' cognitive and psychomotor performance, and a subjective assessment of mental load. The tests did not show any decrease in the comfort of use of the new inserts with improved ballistic resistance compared to the inserts currently used.

  20. Ballistic Anisotropic Magnetoresistance of Single-Atom Contacts.

    PubMed

    Schöneberg, J; Otte, F; Néel, N; Weismann, A; Mokrousov, Y; Kröger, J; Berndt, R; Heinze, S

    2016-02-10

    Anisotropic magnetoresistance, that is, the sensitivity of the electrical resistance of magnetic materials on the magnetization direction, is expected to be strongly enhanced in ballistic transport through nanoscale junctions. However, unambiguous experimental evidence of this effect is difficult to achieve. We utilize single-atom junctions to measure this ballistic anisotropic magnetoresistance (AMR). Single Co and Ir atoms are deposited on domains and domain walls of ferromagnetic Fe layers on W(110) to control their magnetization directions. They are contacted with nonmagnetic tips in a low-temperature scanning tunneling microscope to measure the junction conductances. Large changes of the magnetoresistance occur from the tunneling to the ballistic regime due to the competition of localized and delocalized d-orbitals, which are differently affected by spin-orbit coupling. This work shows that engineering the AMR at the single atom level is feasible.

  1. Dynamic Load Measurement of Ballistic Gelatin Impact Using an Instrumented Tube

    NASA Technical Reports Server (NTRS)

    Seidt, J. D.; Periira, J. M.; Hammer, J. T.; Gilat, A.; Ruggeri, C. R.

    2012-01-01

    Bird strikes are a common problem for the aerospace industry and can cause serious damage to an aircraft. Ballistic gelatin is frequently used as a surrogate for actual bird carcasses in bird strike tests. Numerical simulations of these tests are used to supplement experimental data, therefore it is necessary to use numerical modeling techniques that can accurately capture the dynamic response of ballistic gelatin. An experimental technique is introduced to validate these modeling techniques. A ballistic gelatin projectile is fired into a strike plate attached to a 36 in. long sensor tube. Dynamic load is measured at two locations relative to the strike plate using strain gages configured in a full Wheatstone bridge. Data from these experiments are used to validate a gelatin constitutive model. Simulations of the apparatus are analyzed to investigate its performance.

  2. Study of ballistic mode Mercury Orbiter missions. Volume 1: Summary report

    NASA Technical Reports Server (NTRS)

    Hollenbeck, G. R.

    1973-01-01

    A summary is given of the scope, approach, and major results of the study of ballistic mode Mercury orbit missions (the Mariner Venus-Mercury spacecraft). The performance potential of ballistic flight mode is presented along with a study of alternate flight techniques. Orbit selection considerations are discussed in terms of the thermal environment of Mercury. Orbiter science experiments are summarized. Technology assessments were conducted for major subsystems appropriate to spin-stabilized and three-axis-stabilized spacecraft designs. Conclusions from this study are: ballistic mode Mercury orbiter missions offer adequate performance for effective follow-up of the MVM'73 science findings; the existing and programmed technology base is adequate for implementation of Mercury orbit spacecraft design; and when pending MVM flyby has been accomplished and the results analyzed, the data base will be adequate to support detailed orbiter spacecraft design efforts.

  3. The Advantages of Normalizing Electromyography to Ballistic Rather than Isometric or Isokinetic Tasks.

    PubMed

    Suydam, Stephen M; Manal, Kurt; Buchanan, Thomas S

    2017-07-01

    Isometric tasks have been a standard for electromyography (EMG) normalization stemming from anatomic and physiologic stability observed during contraction. Ballistic dynamic tasks have the benefit of eliciting maximum EMG signals for normalization, despite having the potential for greater signal variability. It is the purpose of this study to compare maximum voluntary isometric contraction (MVIC) to nonisometric tasks with increasing degrees of extrinsic variability, ie, joint range of motion, velocity, rate of contraction, etc., to determine if the ballistic tasks, which elicit larger peak EMG signals, are more reliable than the constrained MVIC. Fifteen subjects performed MVIC, isokinetic, maximum countermovement jump, and sprint tasks while EMG was collected from 9 muscles in the quadriceps, hamstrings, and lower leg. The results revealed the unconstrained ballistic tasks were more reliable compared to the constrained MVIC and isokinetic tasks for all triceps surae muscles. The EMG from sprinting was more reliable than the constrained cases for both the hamstrings and vasti. The most reliable EMG signals occurred when the body was permitted its natural, unconstrained motion. These results suggest that EMG is best normalized using ballistic tasks to provide the greatest within-subject reliability, which beneficially yield maximum EMG values.

  4. Steady-state heat transport: Ballistic-to-diffusive with Fourier's law

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maassen, Jesse, E-mail: jmaassen@purdue.edu; Lundstrom, Mark

    2015-01-21

    It is generally understood that Fourier's law does not describe ballistic phonon transport, which is important when the length of a material is similar to the phonon mean-free-path. Using an approach adapted from electron transport, we demonstrate that Fourier's law and the heat equation do capture ballistic effects, including temperature jumps at ideal contacts, and are thus applicable on all length scales. Local thermal equilibrium is not assumed, because allowing the phonon distribution to be out-of-equilibrium is important for ballistic and quasi-ballistic transport. The key to including the non-equilibrium nature of the phonon population is to apply the proper boundarymore » conditions to the heat equation. Simple analytical solutions are derived, showing that (i) the magnitude of the temperature jumps is simply related to the material properties and (ii) the observation of reduced apparent thermal conductivity physically stems from a reduction in the temperature gradient and not from a reduction in actual thermal conductivity. We demonstrate how our approach, equivalent to Fourier's law, easily reproduces results of the Boltzmann transport equation, in all transport regimes, even when using a full phonon dispersion and mean-free-path distribution.« less

  5. The application of computed tomography in wound ballistics research

    NASA Astrophysics Data System (ADS)

    Tsiatis, Nick; Moraitis, Konstantinos; Papadodima, Stavroula; Spiliopoulou, Chara; Kelekis, Alexis; Kelesis, Christos; Efstathopoulos, Efstathios; Kordolaimi, Sofia; Ploussi, Agapi

    2015-09-01

    In wound ballistics research there is a relationship between the data that characterize a bullet and the injury resulted after shooting when it perforates the human body. The bullet path in the human body following skin perforation as well as the damaging effect cannot always be predictable as they depend on various factors such as the bullet's characteristics (velocity, distance, type of firearm and so on) and the tissue types that the bullet passes through. The purpose of this presentation is to highlight the contribution of Computed Tomography (CT) in wound ballistics research. Using CT technology and studying virtual “slices” of specific areas on scanned human bodies, allows the evaluation of density and thickness of the skin, the subcutaneous tissue, the muscles, the vital organs and the bones. Density data taken from Hounsfield units can be converted in g/ml by using the appropriate software. By evaluating the results of this study, the anatomy of the human body utilizing ballistic gel will be reproduced in order to simulate the path that a bullet follows. The biophysical analysis in wound ballistics provides another application of CT technology, which is commonly used for diagnostic and therapeutic purposes in various medical disciplines.

  6. Development of Ballistic Protection Based on Precipitation-Hardened Composite Material

    NASA Astrophysics Data System (ADS)

    Chernyshov, E. A.; Romanov, A. D.; Romanova, E. A.; Myl'nikov, V. V.

    2018-03-01

    The possibility of application of an aluminum-based precipitation-hardened composite material for purposes of ballistic protection is considered. Experimental data on A6 aluminum-based alloy reinforced with alumina particles are presented.

  7. Analysis of Multiple-Impact Ballistic Performance of a Tempered Glass Laminate with a Strike Face Film

    DTIC Science & Technology

    2014-02-01

    a 0.18 in thick polymer interlayer between two layers of 0.5 in tempered silica based “ soda lime ” glass . A 0.08 in shatter resistant film was...AFCEC-CX-TY-TR-2014-0005 ANALYSIS OF MULTIPLE-IMPACT BALLISTIC PERFORMANCE OF A TEMPERED GLASS LAMINATE WITH A STRIKE FACE FILM Michael A. Magrini...Interim Technical Report 3 JAN 2012 to 2 JAN 2013 Analysis of Multiple-Impact Ballistic Performance of A Tempered Glass Laminate with a Strike Face Film

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flax, A.

    The growing number of short- to medium-range ballistic missiles (SMBMs) in the inventories of many smaller states that have had recent or less recent armed conflicts with one another has been a source of concern to many countries. Inevitably this concern over ballistic missiles had been linked to their use as delivery vehicles for {open_quotes}weapons of mass destruction{close_quotes}, a category that now includes nuclear, chemical and biological weapons. But it can be argued that this categorization is not particularly useful as a point of departure for discussions of ballistic missile defense (BMD) against SMBMs.

  9. Space-based infrared sensors of space target imaging effect analysis

    NASA Astrophysics Data System (ADS)

    Dai, Huayu; Zhang, Yasheng; Zhou, Haijun; Zhao, Shuang

    2018-02-01

    Target identification problem is one of the core problem of ballistic missile defense system, infrared imaging simulation is an important means of target detection and recognition. This paper first established the space-based infrared sensors ballistic target imaging model of point source on the planet's atmosphere; then from two aspects of space-based sensors camera parameters and target characteristics simulated atmosphere ballistic target of infrared imaging effect, analyzed the camera line of sight jitter, camera system noise and different imaging effects of wave on the target.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karp, A.

    Observers of Third World security watch for new weapon systems that promise to make the poor the military equals of the rich. Ballistic missiles, which combine the nuclear weapon and precision-guided munition, are a disturbing possibility that warrants regulation of the flow of ballistic missile technology. It is imperative to have a policy delineating the risks involved with ballistic missiles as a basis for action and consistency and for working with other technology suppliers. The US should initiate discussions aimed at establishing a missile technology suppliers' regime before Third World countries actually deploy nuclear missiles.

  11. Compression of helium to high pressures and temperatures using a ballistic piston apparatus

    NASA Technical Reports Server (NTRS)

    Roman, B. P.; Rovel, G. P.; Lewis, M. J.

    1971-01-01

    Some preliminary experiments are described which were carried out in a high enthalpy laboratory to investigate the compression of helium, a typical shock-tube driver gas, to very high pressures and temperatures by means of a ballistic piston. The purpose of these measurements was to identify any problem areas in the compression process, to determine the importance of real gas effects duDC 47355s process, and to establish the feasibility of using a ballistic piston apparatus to achieve temperatures in helium in excess of 10,000 K.

  12. Missiles for Asia The Need for Operational Analysis of U.S. Theater Ballistic Missiles in the Pacific

    DTIC Science & Technology

    2016-01-01

    C O R P O R A T I O N Missiles for Asia? The Need for Operational Analysis of U.S. Theater Ballistic Missiles in the Pacific Jacob L. Heim • The...durability of the Intermediate-Range Nuclear Forces Treaty is in doubt. • China’s rapid military modernization could threaten U.S. forces. • Theater ...conventional land-based theater ballistic missiles (TBMs) could add to the U.S. portfolio of strike capabilities. In particular, the U.S. Army should ana- lyze

  13. A Systems Approach to Finding Cost-Effective Alternatives to European Ballistic Missile Defense

    DTIC Science & Technology

    2013-09-01

    has holes in its ability to cover the entire region as required. What are the existing approaches to ballistic missile defense in Europe? 4. What Are...however, this report focuses on ballistic missiles which use stellar or inertial guidance systems which are not subject to electromagnetic...location as the Baseline system (35.6° N, 32.5° E) while the other was placed north of Turkey in the Black Sea (41.5° N, 38.1° E). Each Aegis ship was

  14. An investigation into the relationship between thermal shock resistance and ballistic performance of ceramic materials

    NASA Astrophysics Data System (ADS)

    Beaumont, Robert

    Currently, there are no reliable methods for screening potential armour materials and hence full-scale ballistic trials are needed. These are both costly and time-consuming in terms of the actual test and also in the materials development that needs to take place to produce sufficient material to give a meaningful result. Whilst it will not be possible to dispense with ballistic trials before material deployment in armour applications, the ability to shorten the development cycle would be advantageous. The thermal shock performance of ceramic armour materials has been highlighted as potential marker for ballistic performance. Hence the purpose of this study was to investigate this further. A new thermal shock technique that reproduced features relevant to ballistic testing was sought. As it would be beneficial to have a simple test that did not use much material, a water-drop method was adopted. This was combined with a variety of characterisation techniques, administered pre- and post-shock. The methods included measurement of the amplitude of ultrasonic wave transmission through the sample alongside residual strength testing using a biaxial ball-on-ball configuration and reflected light and confocal microscopy. Once the protocols had been refined the testing regime was applied to a group of ceramic materials. The materials selected were from two broad groups: alumina and carbide materials. Carbide ceramics show superior performance to alumina ceramics in ballistic applications so it was essential that any screening test would be easily able to differentiate the two groups. Within the alumina family, two commercially available materials, AD995 and Sintox FA, were selected. These were tested alongside three developmental silicon carbide-boron carbide composites, which had identical chemical compositions but different microstructures and thus presented more of a challenge in terms of differentiation. The results from the various tests were used to make predictions about the relative ballistic performances. The tests showed that all of the composites would outperform the alumina materials. Further, all of the tests led to the prediction that AD995 would be better ballistically than Sintox FA, possibly up to a factor of two better. The predictions were in very good agreement with literature values for depth-of-penetration testing. The situation was more complex for the carbide materials, with different tests leading to slightly different predictions. However, the predictions from the ultrasonic tests were consistent with the available ballistic data. Indeed, the ultrasonic data proved to be the most consistent predictor of ballistic performance, supporting the view that the total defect population is more relevant than a ‘critical flaw’ concept. Thus, it can be concluded that with further development, and subject to validation across a wider spread of materials and microstructures, thermal shock testing coupled with ultrasonic measurements could form the basis of a future screening test for ceramics for armour applications.

  15. Feasibility of ballistic strength training in sub-acute stroke: A randomized, controlled, assessor-blinded pilot study.

    PubMed

    Hendrey, Genevieve; Clark, Ross A; Holland, Anne E; Mentiplay, Benjamin F; Davis, Carly; Windfeld-Lund, Cristie; Raymond, Melissa J; Williams, Gavin

    2018-05-30

    To establish the feasibility and effectiveness of a six week ballistic strength training protocol in people with stroke. Randomized, controlled, assessor-blinded study. Sub-acute inpatient rehabilitation. Consecutively admitted inpatients with a primary diagnosis of first ever stroke with lower limb weakness, functional ambulation category score of ≥3, and ability to walk ≥14m were screened for eligibility to recruit 30 participants for randomization. Participants were randomized to standard therapy or ballistic strength training three times per week for six weeks. The primary aim was to evaluate feasibility and outcomes included recruitment rate, participant retention and attrition, feasibility of the exercise protocol, therapist burden and participant safety. Secondary outcomes included measures of mobility, lower limb muscle strength, muscle power and quality of life. Thirty participants (11% of those screened) with mean age of 50 (SD 18) years were randomized. The median number of sessions attended was 15/18 and 17/18 for the ballistic and control groups respectively. Earlier than expected discharge home (n=4) and illness (n=7) were the most common reasons for non-attendance. Participants performed the exercises safely, with no study-related adverse events. There were significant (p<0.05) between-group changes favoring the ballistic group for comfortable gait velocity (mean difference (MD) 0.31m/s, 95% confidence interval CI: 0.08 to 0.52), muscle power, as measured by peak jump height (MD 8cm, 95% CI: 3 to 13) and peak propulsive velocity (MD 64cm/s, 95% CI: 17 to 112). Ballistic training was safe and feasible in select ambulant people with stroke. Similar rates of retention and attrition suggest that ballistic training was acceptable to patients. Secondary outcomes provide promising results that warrant further investigation in a larger trial. Copyright © 2018. Published by Elsevier Inc.

  16. Potentiation Following Ballistic and Nonballistic Complexes: The Effect of Strength Level.

    PubMed

    Suchomel, Timothy J; Sato, Kimitake; DeWeese, Brad H; Ebben, William P; Stone, Michael H

    2016-07-01

    Suchomel, TJ, Sato, K, DeWeese, BH, Ebben, WP, and Stone, MH. Potentiation following ballistic and nonballistic complexes: the effect of strength level. J Strength Cond Res 30(7): 1825-1833, 2016-The purpose of this study was to compare the temporal profile of strong and weak subjects during ballistic and nonballistic potentiation complexes. Eight strong (relative back squat = 2.1 ± 0.1 times body mass) and 8 weak (relative back squat = 1.6 ± 0.2 times body mass) males performed squat jumps immediately and every minute up to 10 minutes following potentiation complexes that included ballistic or nonballistic concentric-only half-squat (COHS) performed at 90% of their 1 repetition maximum COHS. Jump height (JH) and allometrically scaled peak power (PPa) were compared using a series of 2 × 12 repeated measures analyses of variance. No statistically significant strength level main effects for JH (p = 0.442) or PPa (p = 0.078) existed during the ballistic condition. In contrast, statistically significant main effects for time existed for both JH (p = 0.014) and PPa (p < 0.001); however, no statistically significant pairwise comparisons were present (p > 0.05). Statistically significant strength level main effects existed for PPa (p = 0.039) but not for JH (p = 0.137) during the nonballistic condition. Post hoc analysis revealed that the strong subjects produced statistically greater PPa than the weaker subjects (p = 0.039). Statistically significant time main effects existed for time existed for PPa (p = 0.015), but not for JH (p = 0.178). No statistically significant strength level × time interaction effects for JH (p = 0.319) or PPa (p = 0.203) were present for the ballistic or nonballistic conditions. Practical significance indicated by effect sizes and the relationships between maximum potentiation and relative strength suggest that stronger subjects potentiate earlier and to a greater extent than weaker subjects during ballistic and nonballistic potentiation complexes.

  17. Overlapping Ballistic Ejecta Fields: Separating Distinct Blasts at Kings Bowl, Idaho

    NASA Astrophysics Data System (ADS)

    Borg, C.; Kobs-Nawotniak, S. E.; Hughes, S. S.; Sears, D. W. G.; Heldmann, J. L.; Lim, D. S. S.; Haberle, C. W.; Sears, H.; Elphic, R. C.; Kobayashi, L.; Garry, W. B.; Neish, C.; Karunatillake, S.; Button, N.; Purcell, S.; Mallonee, H.; Ostler, B.

    2015-12-01

    Kings Bowl is a ~2200ka pit crater created by a phreatic blast along a volcanic fissure in the eastern Snake River Plain (ESRP), Idaho. The main crater measures approximately 80m in length, 30m in width, and 30m in depth, with smaller pits located nearby on the Great Rift fissure, and has been targeted by the FINESSE team as a possible analogue for Cyane Fossae, Mars. The phreatic eruption is believed to have occurred due to the interaction of groundwater with lava draining back into the fissure following a lava lake high stand, erupting already solidified basalt from this and previous ERSP lava flows. The contemporaneous draw back of the lava with the explosions may conceal some smaller possible blast pits as more lava drained into the newly formed pits. Ballistic ejecta from the blasts occur on both sides of the fissure. To the east, the ballistic blocks are mantled by fine tephra mixed with eolian dust, the result of a westerly wind during the explosions. We use differential GPS to map the distribution of ballistic blocks on the west side of the fissure, recording position, percent vesiculation, and the length of 3 mutually perpendicular axes for each block >20cm along multiple transects parallel to the fissure. From the several hundred blocks recorded, we have been able to separate the ballistic field into several distinct blast deposits on the basis of size distributions and block concentration. The smaller pits identified from the ballistic fields correspond broadly to the northern and southern limits of the tephra/dust field east of the fissure. Soil formation and bioturbation of the tephra by sagebrush have obliterated any tephrostratigraphy that could have been linked to individual blasts. The ballistic block patterns at Kings Bowl may be used to identify distinct ejecta groups in high-resolution imagery of Mars or other planetary bodies.

  18. IMM tracking of a theater ballistic missile during boost phase

    NASA Astrophysics Data System (ADS)

    Hutchins, Robert G.; San Jose, Anthony

    1998-09-01

    Since the SCUD launches in the Gulf War, theater ballistic missile (TBM) systems have become a growing concern for the US military. Detection, tracking and engagement during boost phase or shortly after booster cutoff are goals that grow in importance with the proliferation of weapons of mass destruction. This paper addresses the performance of tracking algorithms for TBMs during boost phase and across the transition to ballistic flight. Three families of tracking algorithms are examined: alpha-beta-gamma trackers, Kalman-based trackers, and the interactive multiple model (IMM) tracker. In addition, a variation on the IMM to include prior knowledge of a booster cutoff parameter is examined. Simulated data is used to compare algorithms. Also, the IMM tracker is run on an actual ballistic missile trajectory. Results indicate that IMM trackers show significant advantage in tracking through the model transition represented by booster cutoff.

  19. A novel navigation method used in a ballistic missile

    NASA Astrophysics Data System (ADS)

    Qian, Hua-ming; Sun, Long; Cai, Jia-nan; Peng, Yu

    2013-10-01

    The traditional strapdown inertial/celestial integrated navigation method used in a ballistic missile cannot accurately estimate the accelerometer bias. It might cause a divergence of navigation errors. To solve this problem, a new navigation method named strapdown inertial/starlight refractive celestial integrated navigation is proposed. To verify the feasibility of the proposed method, a simulated program of a ballistic missile is presented. The simulation results indicated that, when multiple refraction stars are used, the proposed method can accurately estimate the accelerometer bias, and suppress the divergence of navigation errors completely. Specifically, in order to apply this method to a ballistic missile, a novel measurement equation based on stellar refraction was developed. Furthermore a method to calculate the number of refraction stars observed by the stellar sensor was given. Finally, the relationship between the number of refraction stars used and the navigation accuracy is analysed.

  20. Localization and Ballistic Diffusion for the Tempered Fractional Brownian-Langevin Motion

    NASA Astrophysics Data System (ADS)

    Chen, Yao; Wang, Xudong; Deng, Weihua

    2017-10-01

    This paper discusses the tempered fractional Brownian motion (tfBm), its ergodicity, and the derivation of the corresponding Fokker-Planck equation. Then we introduce the generalized Langevin equation with the tempered fractional Gaussian noise for a free particle, called tempered fractional Langevin equation (tfLe). While the tfBm displays localization diffusion for the long time limit and for the short time its mean squared displacement (MSD) has the asymptotic form t^{2H}, we show that the asymptotic form of the MSD of the tfLe transits from t^2 (ballistic diffusion for short time) to t^{2-2H}, and then to t^2 (again ballistic diffusion for long time). On the other hand, the overdamped tfLe has the transition of the diffusion type from t^{2-2H} to t^2 (ballistic diffusion). The tfLe with harmonic potential is also considered.

  1. Microbial arms race: Ballistic "nematocysts" in dinoflagellates represent a new extreme in organelle complexity.

    PubMed

    Gavelis, Gregory S; Wakeman, Kevin C; Tillmann, Urban; Ripken, Christina; Mitarai, Satoshi; Herranz, Maria; Özbek, Suat; Holstein, Thomas; Keeling, Patrick J; Leander, Brian S

    2017-03-01

    We examine the origin of harpoon-like secretory organelles (nematocysts) in dinoflagellate protists. These ballistic organelles have been hypothesized to be homologous to similarly complex structures in animals (cnidarians); but we show, using structural, functional, and phylogenomic data, that nematocysts evolved independently in both lineages. We also recorded the first high-resolution videos of nematocyst discharge in dinoflagellates. Unexpectedly, our data suggest that different types of dinoflagellate nematocysts use two fundamentally different types of ballistic mechanisms: one type relies on a single pressurized capsule for propulsion, whereas the other type launches 11 to 15 projectiles from an arrangement similar to a Gatling gun. Despite their radical structural differences, these nematocysts share a single origin within dinoflagellates and both potentially use a contraction-based mechanism to generate ballistic force. The diversity of traits in dinoflagellate nematocysts demonstrates a stepwise route by which simple secretory structures diversified to yield elaborate subcellular weaponry.

  2. ["Piggyback" shot: ballistic parameters of two simultaneously discharged airgun pellets].

    PubMed

    Frank, Matthias; Schönekess, Holger C; Grossjohann, Rico; Ekkernkamp, Axel; Bockholdt, Britta

    2014-01-01

    Green and Good reported an uncommon case of homicide committed with an air rifle in 1982 (Am. J. Forensic Med. Pathol. 3: 361-365). The fatal wound was unusual in that two airgun pellets were loaded in so-called "piggyback" fashion into a single shot air rifle. Lack of further information on the ballistic characteristics of two airgun pellets as opposed to one conventionally loaded projectile led to this investigation. The mean kinetic energy (E) of the two pellets discharged in "piggyback" fashion was E = 3.6 J and E = 3.4 J, respectively. In comparison, average kinetic energy values of E = 12.5 J were calculated for conventionally discharged single diabolo pellets. Test shots into ballistic soap confirmed the findings of a single entrance wound as reported by Green and Good. While the ballistic background of pellets discharged in "piggyback" fashion could be clarified, the reason behind this mode of shooting remains unclear.

  3. Ballistic aggregation in systems of inelastic particles: Cluster growth, structure, and aging

    NASA Astrophysics Data System (ADS)

    Paul, Subhajit; Das, Subir K.

    2017-07-01

    We study far-from-equilibrium dynamics in models of freely cooling granular gas and ballistically aggregating compact clusters. For both the cases, from event-driven molecular dynamics simulations, we have presented detailed results on structure and dynamics in space dimensions d =1 and 2. Via appropriate analyses it has been confirmed that the ballistic aggregation mechanism applies in d =1 granular gases as well. Aging phenomena for this mechanism, in both the dimensions, have been studied via the two-time density autocorrelation function. This quantity is demonstrated to exhibit scaling property similar to that in the standard phase transition kinetics. The corresponding functional forms have been quantified and the outcomes have been discussed in connection with the structural properties. Our results on aging establish a more complete equivalence between the granular gas and the ballistic aggregation models in d =1 .

  4. Ballistic parameters and trauma potential of pistol crossbows.

    PubMed

    Frank, Matthias; Schikorr, Wolfgang; Tesch, Ralf; Werner, Ronald; Hanisch, Steffen; Peters, Dieter; Ekkernkamp, Axel; Bockholdt, Britta; Seifert, Julia

    2013-07-01

    Hand-held pistol crossbows, which are smaller versions of conventional crossbows, have recently increased in popularity. Similar to conventional crossbows, life threatening injuries due to bolts discharged from pistol crossbows are reported in forensic and traumatological literature. While the ballistic background of conventional crossbows is comprehensively investigated, there are no investigations on the characteristic ballistic parameters (draw force, potential energy, recurve factor, kinetic energy, and efficiency) of pistol crossbows. Two hand-held pistol crossbows (Barnett Commando and Mini Cross Bow, rated draw force 362.9 N or 80 lbs) were tested. The maximum draw force was investigated using a dynamic tensile testing machine (TIRAtest 2705, TIRA GmbH). The potential energy was determined graphically by polynomial regression as area under the force-draw curve. External ballistic parameters of the bolts discharged from pistol crossbows were measured using a redundant ballistic speed measurement system (Dual-BMC 21a and Dual-LS 1000, Werner Mehl Kurzzeitmesstechnik). The average maximum draw force was 190.3 and 175.6 N for the Barnett and Mini Cross Bow, respectively. The corresponding total energy expended was 10.7 and 11 J, respectively. The recurve factor was calculated to be 0.705 and 1.044, respectively. Average bolt velocity was measured 43 up to 52 m/s. The efficiency was calculated up to 0.94. To conclude, this work provides the pending ballistic data on this special subgroup of crossbows which operate on a remarkable low kinetic energy level. Furthermore, it demonstrates that the nominal draw force pretended in the sales brochure is grossly exaggerated.

  5. Deterrence of ballistic missile systems and their effects on today's air operations

    NASA Astrophysics Data System (ADS)

    Durak, Hasan

    2015-05-01

    Lately, the effect-based approach has gained importance in executing air operations. Thus, it makes more successful in obtaining the desired results by breaking the enemy's determination in a short time. Air force is the first option to be chosen in order to defuse the strategic targets. However, the problems such as the defense of targets and country, radars, range…etc. becoming serious problems. At this level ballistic missiles emerge as a strategic weapon. Ultimate emerging technologies guided by the INS and GPS can also be embedded with multiple warheads and reinforced with conventional explosive, ballistic missiles are weapons that can destroy targets with precision. They have the advantage of high speed, being easily launched from every platform and not being easily detected by air defense systems contrary to other air platforms. While these are the advantages, there are also disadvantages of the ballistic missiles. The high cost, unavailability of nuclear, biological and chemical weapons, and its limited effect while using conventional explosives against destroying the fortified targets are the disadvantages. The features mentioned above should be considered as limitation to the impact of the ballistic missiles. The aim is to impose the requests on enemies without starting a war with all components and to ensure better implementation of the operation functions during the air operations. In this study, effects of ballistic missiles in the future on air battle theatre will be discussed in the beginning, during the process and at the end phase of air operations within the scope of an effect-based approach.

  6. Alternatives for Boost-Phase Missile Defense

    DTIC Science & Technology

    2004-07-01

    NFIRE ) to better understand the characteristics of that signature for intercontinental ballistic missiles (ICBMs). The information that NFIRE might...ballistic missile Isp: specific impulse kg: kilogram km: kilometer MDA: Missile Defense Agency NFIRE : Near-Field Infrared Experiment NMD: national missile

  7. Fiber-modified polyurethane foam for ballistic protection

    NASA Technical Reports Server (NTRS)

    Fish, R. H.; Parker, J. A.; Rosser, R. W.

    1975-01-01

    Closed-cell, semirigid, fiber-loaded, self-extinguishing polyurethane foam material fills voids around fuel cells in aircraft. Material prevents leakage of fuel and spreading of fire in case of ballistic incendiary impact. It also protects fuel cell in case of exterior fire.

  8. A study of performance and cost improvement potential of the 120 inch (3.05 m) diameter solid rocket motor. Volume 1: Summary report

    NASA Technical Reports Server (NTRS)

    Backlund, S. J.; Rossen, J. N.

    1971-01-01

    A parametric study of ballistic modifications to the 120 inch diameter solid propellant rocket engine which forms part of the Air Force Titan 3 system is presented. 576 separate designs were defined and 24 were selected for detailed analysis. Detailed design descriptions, ballistic performance, and mass property data were prepared for each design. It was determined that a relatively simple change in design parameters could provide a wide range of solid propellant rocket engine ballistic characteristics for future launch vehicle applications.

  9. Quasiballistic quantum transport through Ge/Si core/shell nanowires

    NASA Astrophysics Data System (ADS)

    Kotekar-Patil, D.; Nguyen, B.-M.; Yoo, J.; Dayeh, S. A.; Frolov, S. M.

    2017-09-01

    We study signatures of ballistic quantum transport of holes through Ge/Si core/shell nanowires at low temperatures. We observe Fabry-Pérot interference patterns as well as conductance plateaus at integer multiples of 2e 2/h at zero magnetic field. Magnetic field evolution of these plateaus reveals relatively large effective Landé g-factors. Ballistic effects are observed in nanowires with silicon shell thickness of 1-3 nm, but not in bare germanium wires. These findings inform the future development of spin and topological quantum devices which rely on ballistic sub-band-resolved transport.

  10. Digital pulse processing for planar TlBr detectors, optimized for ballistic deficit and charge-trapping effect

    NASA Astrophysics Data System (ADS)

    Nakhostin, M.; Hitomi, K.

    2012-05-01

    The energy resolution of thallium bromide (TlBr) detectors is significantly limited by charge-trapping effect and pulse ballistic deficit, caused by the slow charge collection time. A digital pulse processing algorithm has been developed aiming to compensate for charge-trapping effect, while minimizing pulse ballistic deficit. The algorithm is examined using a 1 mm thick TlBr detector and an excellent energy resolution of 3.37% at 662 keV is achieved at room temperature. The pulse processing algorithms are presented in recursive form, suitable for real-time implementations.

  11. Targeting Ballistic Lunar Capture Trajectories Using Periodic Orbits in the Sun-Earth CRTBP

    NASA Technical Reports Server (NTRS)

    Cooley, D.S.; Griesemer, Paul Ricord; Ocampo, Cesar

    2009-01-01

    A particular periodic orbit in the Earth-Sun circular restricted three body problem is shown to have the characteristics needed for a ballistic lunar capture transfer. An injection from a circular parking orbit into the periodic orbit serves as an initial guess for a targeting algorithm. By targeting appropriate parameters incrementally in increasingly complicated force models and using precise derivatives calculated from the state transition matrix, a reliable algorithm is produced. Ballistic lunar capture trajectories in restricted four body systems are shown to be able to be produced in a systematic way.

  12. Early Rockets

    NASA Image and Video Library

    1957-03-01

    The Jupiter rocket was designed and developed by the Army Ballistic Missile Agency (ABMA). ABMA launched the Jupiter-A at Cape Canaveral, Florida, on March 1, 1957. The Jupiter vehicle was a direct derivative of the Redstone. The Army Ballistic Missile Agency (ABMA) at Redstone Arsenal, Alabama, continued Jupiter development into a successful intermediate ballistic missile, even though the Department of Defense directed its operational development to the Air Force. ABMA maintained a role in Jupiter RD, including high-altitude launches that added to ABMA's understanding of rocket vehicle operations in the near-Earth space environment. It was knowledge that paid handsome dividends later.

  13. Mathematical model and software for investigation of internal ballistic processes in high-speed projectile installations

    NASA Astrophysics Data System (ADS)

    Diachkovskii, A. S.; Zykova, A. I.; Ishchenko, A. N.; Kasimov, V. Z.; Rogaev, K. S.; Sidorov, A. D.

    2017-11-01

    This paper describes a software package that allows to explore the interior ballistics processes occurring in a shot scheme with bulk charges using propellant pasty substances at various loading schemes, etc. As a mathematical model, a model of a polydisperse mixture of non-deformable particles and a carrier gas phase is used in the quasi-one-dimensional approximation. Writing the equations of the mathematical model allows to use it to describe a broad class of interior ballistics processes. Features of the using approach are illustrated by calculating the ignition period for the charge of tubular propellant.

  14. Model of ballistic targets' dynamics used for trajectory tracking algorithms

    NASA Astrophysics Data System (ADS)

    Okoń-FÄ fara, Marta; Kawalec, Adam; Witczak, Andrzej

    2017-04-01

    There are known only few ballistic object tracking algorithms. To develop such algorithms and to its further testing, it is necessary to implement possibly simple and reliable objects' dynamics model. The article presents the dynamics' model of a tactical ballistic missile (TBM) including the three stages of flight: the boost stage and two passive stages - the ascending one and the descending one. Additionally, the procedure of transformation from the local coordinate system to the polar-radar oriented and the global is presented. The prepared theoretical data may be used to determine the tracking algorithm parameters and to its further verification.

  15. Surface morphology of a modified ballistic deposition model.

    PubMed

    Banerjee, Kasturi; Shamanna, J; Ray, Subhankar

    2014-08-01

    The surface and bulk properties of a modified ballistic deposition model are investigated. The deposition rule interpolates between nearest- and next-nearest-neighbor ballistic deposition and the random deposition models. The stickiness of the depositing particle is controlled by a parameter and the type of interparticle force. Two such forces are considered: Coulomb and van der Waals type. The interface width shows three distinct growth regions before eventual saturation. The rate of growth depends more strongly on the stickiness parameter than on the type of interparticle force. However, the porosity of the deposits is strongly influenced by the interparticle force.

  16. Ballistic imaging of the near field in a diesel spray

    NASA Astrophysics Data System (ADS)

    Linne, Mark; Paciaroni, Megan; Hall, Tyler; Parker, Terry

    2006-06-01

    We have developed an optical technique called ballistic imaging to view breakup of the near-field of an atomizing spray. In this paper, we describe the successful use of a time-gated ballistic imaging instrument to obtain single-shot images of core region breakup in a transient, single hole atomizing diesel fuel spray issuing into one atmosphere. We present a sequence of images taken at the nozzle for various times after start of injection, and a sequence taken at various positions downstream of the nozzle exit at a fixed time. These images contain signatures of periodic behavior, voids, and entrainment processes.

  17. Quasiballistic quantum transport through Ge/Si core/shell nanowires

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kotekar-Patil, D.; Nguyen, B-M; Yoo, J.

    We study signatures of ballistic quantum transport of holes through Ge/Si core/shell nanowires at low temperatures. We observe Fabry–Pérot interference patterns as well as conductance plateaus at integer multiples of 2e 2/h at zero magnetic field. Magnetic field evolution of these plateaus reveals relatively large effective Landé g-factors. Ballistic effects are observed in nanowires with silicon shell thickness of 1–3 nm, but not in bare germanium wires. These findings inform the future development of spin and topological quantum devices which rely on ballistic sub-band-resolved transport.

  18. Quasiballistic quantum transport through Ge/Si core/shell nanowires

    DOE PAGES

    Kotekar-Patil, D.; Nguyen, B-M; Yoo, J.; ...

    2017-09-04

    We study signatures of ballistic quantum transport of holes through Ge/Si core/shell nanowires at low temperatures. We observe Fabry–Pérot interference patterns as well as conductance plateaus at integer multiples of 2e 2/h at zero magnetic field. Magnetic field evolution of these plateaus reveals relatively large effective Landé g-factors. Ballistic effects are observed in nanowires with silicon shell thickness of 1–3 nm, but not in bare germanium wires. These findings inform the future development of spin and topological quantum devices which rely on ballistic sub-band-resolved transport.

  19. Spin Seebeck effect and ballistic transport of quasi-acoustic magnons in room-temperature yttrium iron garnet films

    NASA Astrophysics Data System (ADS)

    Noack, Timo B.; Musiienko-Shmarova, Halyna Yu; Langner, Thomas; Heussner, Frank; Lauer, Viktor; Heinz, Björn; Bozhko, Dmytro A.; Vasyuchka, Vitaliy I.; Pomyalov, Anna; L’vov, Victor S.; Hillebrands, Burkard; Serga, Alexander A.

    2018-06-01

    We studied the transient behavior of the spin current generated by the longitudinal spin Seebeck effect (LSSE) in a set of platinum-coated yttrium iron garnet (YIG) films of different thicknesses. The LSSE was induced by means of pulsed microwave heating of the Pt layer and the spin currents were measured electrically using the inverse spin Hall effect in the same layer. We demonstrate that the time evolution of the LSSE is determined by the evolution of the thermal gradient triggering the flux of thermal magnons in the vicinity of the YIG/Pt interface. These magnons move ballistically within the YIG film with a constant group velocity, while their number decays exponentially within an effective propagation length. The ballistic flight of the magnons with energies above 20 K is a result of their almost linear dispersion law, similar to that of acoustic phonons. By fitting the time-dependent LSSE signal for different film thicknesses varying by almost an order of magnitude, we found that the effective propagation length is practically independent of the YIG film thickness. We consider this fact as strong support of a ballistic transport scenario—the ballistic propagation of quasi-acoustic magnons in room temperature YIG.

  20. Ballistic impact response of lipid membranes.

    PubMed

    Zhang, Yao; Meng, Zhaoxu; Qin, Xin; Keten, Sinan

    2018-03-08

    Therapeutic agent loaded micro and nanoscale particles as high-velocity projectiles can penetrate cells and tissues, thereby serving as gene and drug delivery vehicles for direct and rapid internalization. Despite recent progress in developing micro/nanoscale ballistic tools, the underlying biophysics of how fast projectiles deform and penetrate cell membranes is still poorly understood. To understand the rate and size-dependent penetration processes, we present coarse-grained molecular dynamics simulations of the ballistic impact of spherical projectiles on lipid membranes. Our simulations reveal that upon impact, the projectile can pursue one of three distinct pathways. At low velocities below the critical penetration velocity, projectiles rebound off the surface. At intermediate velocities, penetration occurs after the projectile deforms the membrane into a tubular thread. At very high velocities, rapid penetration occurs through localized membrane deformation without tubulation. Membrane tension, projectile velocity and size govern which phenomenon occurs, owing to their positive correlation with the reaction force generated between the projectile and the membrane during impact. Two critical membrane tension values dictate the boundaries among the three pathways for a given system, due to the rate dependence of the stress generated in the membrane. Our findings provide broad physical insights into the ballistic impact response of soft viscous membranes and guide design strategies for drug delivery through lipid membranes using micro/nanoscale ballistic tools.

  1. Effect of helmet liner systems and impact directions on severity of head injuries sustained in ballistic impacts: a finite element (FE) study.

    PubMed

    Tse, Kwong Ming; Tan, Long Bin; Yang, Bin; Tan, Vincent Beng Chye; Lee, Heow Pueh

    2017-04-01

    The current study aims to investigate the effectiveness of two different designs of helmet interior cushion, (Helmet 1: strap-netting; Helmet 2: Oregon Aero foam-padding), and the effect of the impact directions on the helmeted head during ballistic impact. Series of ballistic impact simulations (frontal, lateral, rear, and top) of a full-metal-jacketed bullet were performed on a validated finite element head model equipped with the two helmets, to assess the severity of head injuries sustained in ballistic impacts using both head kinematics and biomechanical metrics. Benchmarking with experimental ventricular and intracranial pressures showed that there is good agreement between the simulations and experiments. In terms of extracranial injuries, top impact had the highest skull stress, still without fracturing the skull. In regard to intracranial injuries, both the lateral and rear impacts generally gave the highest principal strains as well as highest shear strains, which exceed the injury thresholds. Off-cushion impacts were found to be at higher risk of intracranial injuries. The study also showed that the Oregon Aero foam pads helped to reduce impact forces. It also suggested that more padding inserts of smaller size may offer better protection. This provides some insights on future's helmet design against ballistic threats.

  2. Promoting Improved Ballistic Resistance of Transparent Armor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wereszczak, Andrew A; Patel, P; Templeton, D W

    2011-01-01

    Transparent armor is a material or system of materials designed to be optically transparent, yet protect from fragmentation or ballistic impacts. Although engineered to defeat specific threats, or a range of threats, there are general requirements common to all of these designs. The primary requirement for a transparent armor system is to not only defeat the designated threat but also provide a multi-hit capability with minimized distortion of surrounding areas. Ground platforms have several parameters that must be optimized, such as weight, space efficiency, and cost versus performance. Glass exhibits tensile failure stress that is very much dependent on themore » amount of material being stressed, the side being tensile-stressed (i.e., air-versus tin-side if a float glass), and where it is being tensile stressed (i.e., in the middle or near an edge). An axiom arising from those effects is a greater amount of allowable deflection (i.e., higher failure stress) of a ballistically impacted transparent armor will result in improved ballistic resistance. Therefore, the interpretation and management of those tensile-failure-stress dependencies shall ultimately improve ballistic resistance and its predictability of transparent armor. Each of those three dependencies (size, side, and location) in a soda-lime silicate glass is described.« less

  3. Wound ballistics of the pig mandibular angle: a preliminary finite element analysis and experimental study.

    PubMed

    Chen, Yubin; Miao, Yingyun; Xu, Chuan; Zhang, Gang; Lei, Tao; Tan, Yinghui

    2010-04-19

    To study wound ballistics of the mandibular angle, a combined hexahedral-tetrahedral finite element (FE) model of the pig mandible was developed to simulate ballistic impact. An experimental study was carried out by measuring impact load parameters from 14 fresh pig mandibles that were shot at the mandibular angle by a standard 7.62 mm M43 bullet. FE analysis was executed through the LS-DYNA code under impact loads similar to those obtained from the experimental study. The resulting residual velocity, the transferred energy from the bullet to the mandible, and the surface area of the entrance wound had no statistical differences between the FE simulation and the experimental study. However, the mean surface area of the exit wounds in the experimental study was significantly larger than that in the simulation. According to the FE analysis, the stress concentrated zones were mainly located at the region of impact, condylar neck, coronoid process and mandibular body. The simulation results also indicated that trabecular bone had less stress concentration and a lower speed of stress propagation compared with cortical bone. The FE model is appropriate and conforms to the basic principles of wound ballistics. This modeling system will be helpful for further investigations of the biomechanical mechanisms of wound ballistics. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. Attacking the Theater Mobile Ballistic Missile Threat

    DTIC Science & Technology

    1993-06-01

    theater ballistic missile. The development of a long-range rocket dates back at least to 1923 when the German scientist Herman Oberth conceived of...Jeschonnek could no longer tolerate the verbal abuse he received from Reichsmarschall Hermann Goering and Field Marshal Erhard Milch. Jeschonnek

  5. The National Research Council study: "Making sense of ballistic missile defense"

    NASA Astrophysics Data System (ADS)

    Wilkening, Dean A.

    2014-05-01

    This chapter explains and summarizes the main findings of a recent National Research Council study entitled Making Sense of Ballistic Missile Defense: An Assessment of Concepts and Systems for U.S. Boost-Phase Missile Defense in Comparison to Other Alternatives.

  6. Trismus in Face Transplantation Following Ballistic Trauma.

    PubMed

    Krezdorn, Nicco; Alhefzi, Muayyad; Perry, Bridget; Aycart, Mario A; Tasigiorgos, Sotirios; Bueno, Ericka M; Green, Jordan R; Pribaz, Julian J; Pomahac, Bohdan; Caterson, Edward J

    2018-06-01

    Trismus can be a challenging consequence of ballistic trauma to the face, and has rarely been described in the setting of face transplantation. Almost half of all current face transplant recipients in the world received transplantation to restore form and function after a ballistic injury. Here we report our experience and challenges with long standing trismus after face transplantation. We reviewed the medical records of our face transplant recipients whose indication was ballistic injury. We focused our review on trismus and assessed the pre-, peri- and postoperative planning, surgery and functional outcomes. Two patients received partial face transplantation, including the midface for ballistic trauma. Both patients suffered from impaired mouth opening, speech intelligibility, and oral competence. Severe scarring of the temporomandibular joint (TMJ) required intraoperative release in both patients, and additional total condylectomy on the left side 6 months posttransplant for 1 patient. Posttransplant, both patients achieved an improvement in mouth opening; however, there was persistent trismus. One year after transplantation, range of motion of the jaw had improved for both patients. Independent oral food intake was possible 1 year after surgery, although spillage of liquids and mixed consistency solids persisted. Speech intelligibility testing showed impairments in the immediate postoperative period, with improvement to over 85% for both patients at 1 year posttransplant. Ballistic trauma to the face and subsequent reconstructive measures can cause significant scarring and covert injuries to structures such as the TMJ, resulting in long standing trismus. Meticulous individual planning prior to interventions such as face transplantation must take these into account. We encourage intraoperative evaluation of these structures as well as peri- and postoperative treatment when necessary. Due to the nature of the primary injury, functional outcomes after face transplantation in these patients may differ substantially from those of other indications.

  7. Preceding muscle activity influences motor unit discharge and rate of torque development during ballistic contractions in humans

    PubMed Central

    Van Cutsem, Michaël; Duchateau, Jacques

    2005-01-01

    To investigate the effect of initial conditions on the modulation of motor unit discharge during fast voluntary contractions, we compared ballistic isometric contractions of the ankle dorsiflexor muscles that were produced from either a resting state or superimposed on a sustained contraction. The torque of the dorsiflexors and the surface and intramuscular EMGs from the tibialis anterior were recorded. The results showed that the performance of a ballistic contraction from a sustained contraction (∼25% maximal voluntary contraction (MVC)) had a negative effect on the maximal rate of torque development. Although the electromechanical delay was shortened, the EMG activity during the ballistic contraction was less synchronized. These observations were associated with a significant decline in the average discharge rate of single motor units (89.8 ± 3.8 versus 115 ± 5.8 Hz) and in the percentage of units (6.2 versus 15.5% of the whole sample) that exhibited double discharges at brief intervals (= 5 ms). High-threshold units that were not recruited during the sustained contraction displayed the same activation pattern, which indicates that the mechanisms responsible for the decline in discharge rate were not restricted to previously activated units, but appear to influence the entire motor unit pool. When a premotor silent period (SP) was observed at the transition from the sustained muscular activity to the ballistic contraction (19% of the trials), these adjustments in motor unit activity were not present, and the ballistic contractions were similar to those performed from a resting state. Together, these results indicate that initial conditions can influence the capacity for motor unit discharge rate and hence the performance of a fast voluntary contraction. PMID:15539402

  8. Muscle activity during leg strengthening exercise using free weights and elastic resistance: effects of ballistic vs controlled contractions.

    PubMed

    Jakobsen, Markus Due; Sundstrup, Emil; Andersen, Christoffer H; Aagaard, Per; Andersen, Lars L

    2013-02-01

    The present study's aim was to evaluate muscle activity during leg exercises using elastic vs. isoinertial resistance at different exertion and loading levels, respectively. Twenty-four women and eighteen men aged 26-67 years volunteered to participate in the experiment. Electromyographic (EMG) activity was recorded in nine muscles during a standardized forward lunge movement performed with dumbbells and elastic bands during (1) ballistic vs. controlled exertion, and (2) at low, medium and high loads (33%, 66% and 100% of 10 RM, respectively). The recorded EMG signals were normalized to MVC EMG. Knee joint angle was measured using electronic inclinometers. The following results were obtained. Loading intensity affected EMG amplitude in the order: low

  9. The effects of a single bout of exercise on motor memory interference in the trained and untrained hemisphere.

    PubMed

    Lauber, Benedikt; Franke, Steffen; Taube, Wolfgang; Gollhofer, Albert

    2017-04-07

    Increasing evidence suggests that cardiovascular exercise has positive effects on motor memory consolidation. In this study, we investigated whether a single session of high-intensity interval training (HIIT) mitigates the effects of practicing an interfering motor task. Furthermore, learning and interference effects were assessed in the actively trained and untrained limb as it is known that unilateral motor learning can cause bilateral adaptations. Subjects performed a ballistic training and then the HIIT either before (HIIT_before) or after (HIIT_after) practicing an interfering accuracy task (AT). The control group (No_HIIT) did not participate in the HIIT but rested instead. Performance in the ballistic task (BT) was tested before and after the ballistic training, after the exercise and practice of the AT and 24h later. After ballistic training, all groups showed comparable increases in performance in the trained and untrained limb. Despite the practice of the AT, HIIT_before maintained their BT performance after the high-intensity interval training whereas HIIT_after (trend) & No_HIIT showed prominent interference effects. After 24h, HIIT_before still did not show any interference effects but further improved ballistic motor performance. HIIT_after counteracted the interference resulting in a comparable BT performance after 24h than directly after the ballistic training while No_HIIT had a significantly lower BT performance in the retention test. The results were similar in the trained and untrained limb. The current results imply that a single session of cardiovascular exercise can prevent motor interference in the trained and untrained hemisphere. Overall learning was best, and interference least, when HIIT was performed before the interfering motor task. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Ballistics and the management of ureteral injuries from high velocity missiles.

    PubMed

    Stutzman, R E

    1977-12-01

    The management of 21 patients with 22 ureteral injuries from high velocity missiles is described and 6 cases are reported in detail. Ballistics should be considered in all wounds of violence. Débridement, internal stents, proximal diversion and thorough drainage are advocated.

  11. Solid propellant grain design and internal ballistics

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The ballistic aspects of grain design were studied to outline the steps necessary to achieve a successful grain design. The relationships of the grain design to steady-state mass balance and erosive burning are considered. Grain design criteria is reviewed, and recommended design criteria are included.

  12. Live RB51 vaccine lyophilized hydrogel formulations with increased shelf life for practical ballistic delivery

    USDA-ARS?s Scientific Manuscript database

    Ballistic delivery capability is essential to delivering vaccines and other therapeutics effectively to both livestock and wildlife in many global scenarios. Here, lyophilized poly(ethylene glycol) (PEG)-glycolide dimethacrylate crosslinked but degradable hydrogels were assessed as payload vehicles ...

  13. 48 CFR 611.602 - General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... involving the security of overseas posts. The DOSESPP includes a wide range of elements of both physical and... security upgrade. This includes installation of forced entry/ballistic resistant (FE/BR) windows and doors...) Forced entry/ballistic resistant (FE/BR) components. This includes doors, windows, and related facilities...

  14. Considerations on Dop (Depth Of Penetration) Test for Evaluation of Ceramics Materials Used in Ballistic Protection

    NASA Astrophysics Data System (ADS)

    Popa, Ioan-Dan; Dobriţa, Florin

    2017-12-01

    Tremendous amount of funds and other resorces were invested in studying the response of ceramic materials under ballistic impact, the main goal being to find a way to increase the protection of soldiers and the vehicles used in the modern battlespace. Using of ceramic materials especially carbon based (carbides), nitrogen based (nitrides) and oxygen based (oxides) ceramics in order to increase the protection level of ballistic equipment could be, sometimes, a big challenge when trying to use the proper test in order to evaluate and compare their performances. The role of the tests is to provide a better understanding of their response in different situations and, as a consequence, to make them more efficient as armour components through future improvements. The paper presents shortly the main tests which are used and eventually standardised for evaluating the ballistic behaviour of the ceramics and other armour components, with a special focus to DOP (Depth of Penetration) Tests.

  15. The Second National Ballistics Imaging Comparison (NBIC-2)

    PubMed Central

    Vorburger, TV; Yen, J; Song, JF; Thompson, RM; Renegar, TB; Zheng, A; Tong, M; Ols, M

    2014-01-01

    In response to the guidelines issued by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB-International) to establish traceability and quality assurance in U.S. crime laboratories, NIST and the ATF initiated a joint project, entitled the National Ballistics Imaging Comparison (NBIC). The NBIC project aims to establish a national traceability and quality system for ballistics identifications in crime laboratories utilizing ATF’s National Integrated Ballistics Information Network (NIBIN). The original NBIC was completed in 2010. In the second NBIC, NIST Standard Reference Material (SRM) 2461 Cartridge Cases were used as reference standards, and 14 experts from 11 U.S. crime laboratories each performed 17 image acquisitions and correlations of the SRM cartridge cases over the course of about half a year. Resulting correlation scores were collected by NIST for statistical analyses, from which control charts and control limits were developed for the proposed quality system and for promoting future assessments and accreditations for firearm evidence in U.S. forensic laboratories in accordance with the ISO 17025 Standard. PMID:26601051

  16. Forensic Evidence and Criminal Investigations: The Impact of Ballistics Information on the Investigation of Violent Crime in Nine Cities.

    PubMed

    King, William R; Campbell, Bradley A; Matusiak, Matthew C; Katz, Charles M

    2017-07-01

    We explore the impact of information from ballistics imaging hit reports on the investigation into violent crimes. Ballistics imaging hits link two crimes involving the same firearm by forensically matching tool marks on the fired bullets or cartridge cases. Interview data collected from detectives who received a hit report were used to explore the relationship between the presence of a hit report and outcomes in 65 gun-related violent crime investigations in nine U.S. police agencies. Findings indicate hit reports rarely contribute to identification, arrest, charging, or sentencing of suspects, because of delays in producing hit reports. On average, hit reports were completed 181.4 days after the focal crime. This delay forces investigations to proceed without the benefit of information from ballistics analysis. Additionally, hit reports rarely contained detailed information that was immediately useful to investigators. Instead, hit reports required additional research by the investigator to unlock useful information. © 2017 American Academy of Forensic Sciences.

  17. Reduction of lunar landing fuel requirements by utilizing lunar ballistic capture.

    PubMed

    Johnson, Michael D; Belbruno, Edward A

    2005-12-01

    Ballistic lunar capture trajectories have been successfully utilized for lunar orbital missions since 1991. Recent interest in lunar landing trajectories has occurred due to a directive from President Bush to return humans to the Moon by 2015. NASA requirements for humans to return to the lunar surface include separation of crew and cargo missions, all lunar surface access, and anytime-abort to return to Earth. Such requirements are very demanding from a propellant standpoint. The subject of this paper is the application of lunar ballistic capture for the reduction of lunar landing propellant requirements. Preliminary studies of the application of weak stability boundary (WSB) trajectories and ballistic capture have shown that considerable savings in low Earth orbit (LEO) mission mass may be realized, on the order of 36% less than conventional Hohmann transfer orbit missions. Other advantages, such as reduction in launch window constraints and reduction of lunar orbit maintenance propellant requirements, have also surfaced from this study.

  18. The method of neutron imaging as a tool for the study of the dynamics of water movement in wet aramid-based ballistic body armour panels

    NASA Astrophysics Data System (ADS)

    Reifler, Felix A.; Lehmann, Eberhard H.; Frei, Gabriel; May, Hans; Rossi, René

    2006-07-01

    A new non-destructive method based on neutron imaging (neutron radiography) to determine the exact water content in aramid-based soft body armour panels is presented. While investigating the ballistic resistance of aramid-based body armour panels under a wet condition, it is important to precisely determine their water content and its chronological development. Using the presented method, the influence of water amount and location on impact testing as well as its time dependence was shown. In the ballistic panels used, spreading of water strongly depended on the kind of quilting. Very fast water migration could be observed when the panels were held vertically. Some first results regarding the water distribution in wet panels immediately after the impact are presented. On the basis of the presented results, requirements for a standard for testing the performance of ballistic panels in the wet state are deduced.

  19. Characteristics of ballistic and blast injuries.

    PubMed

    Powers, David B; Delo, Robert I

    2013-03-01

    Ballistic injury wounds are formed by variable interrelated factors, such as the nature of the tissue, the compositional makeup of the bullet, distance to the target, and the velocity, shape, and mass of the of the projectile. This complex arrangement, with the ultimate outcome dependent on each other, makes the prediction of wounding potential difficult to assess. As the facial features are the component of the body most involved in a patient's personality and interaction with society, preservation of form, cosmesis, and functional outcome should remain the primary goals in the management of ballistic injury. A logical, sequential analysis of the injury patterns to the facial complex is an absolutely necessary component for the treatment of craniomaxillofacial ballistic injuries. Fortunately, these skill sets should be well honed in all craniomaxillofacial surgeons through their exposure to generalized trauma, orthognathic, oncologic, and cosmetic surgery patients. Identification of injured tissues, understanding the functional limitations of these injuries, and preservation of both hard and soft tissues minimizing the need for tissue replacement are paramount.

  20. The Second National Ballistics Imaging Comparison (NBIC-2).

    PubMed

    Vorburger, T V; Yen, J; Song, J F; Thompson, R M; Renegar, T B; Zheng, A; Tong, M; Ols, M

    2014-01-01

    In response to the guidelines issued by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB-International) to establish traceability and quality assurance in U.S. crime laboratories, NIST and the ATF initiated a joint project, entitled the National Ballistics Imaging Comparison (NBIC). The NBIC project aims to establish a national traceability and quality system for ballistics identifications in crime laboratories utilizing ATF's National Integrated Ballistics Information Network (NIBIN). The original NBIC was completed in 2010. In the second NBIC, NIST Standard Reference Material (SRM) 2461 Cartridge Cases were used as reference standards, and 14 experts from 11 U.S. crime laboratories each performed 17 image acquisitions and correlations of the SRM cartridge cases over the course of about half a year. Resulting correlation scores were collected by NIST for statistical analyses, from which control charts and control limits were developed for the proposed quality system and for promoting future assessments and accreditations for firearm evidence in U.S. forensic laboratories in accordance with the ISO 17025 Standard.

  1. Interior and exterior ballistics coupled optimization with constraints of attitude control and mechanical-thermal conditions

    NASA Astrophysics Data System (ADS)

    Liang, Xin-xin; Zhang, Nai-min; Zhang, Yan

    2016-07-01

    For solid launch vehicle performance promotion, a modeling method of interior and exterior ballistics associated optimization with constraints of attitude control and mechanical-thermal condition is proposed. Firstly, the interior and external ballistic models of the solid launch vehicle are established, and the attitude control model of the high wind area and the stage of the separation is presented, and the load calculation model of the drag reduction device is presented, and thermal condition calculation model of flight is presented. Secondly, the optimization model is established to optimize the range, which has internal and external ballistic design parameters as variables selected by sensitivity analysis, and has attitude control and mechanical-thermal conditions as constraints. Finally, the method is applied to the optimal design of a three stage solid launch vehicle simulation with differential evolution algorithm. Simulation results are shown that range capability is improved by 10.8%, and both attitude control and mechanical-thermal conditions are satisfied.

  2. Impulse-variability theory: implications for ballistic, multijoint motor skill performance.

    PubMed

    Urbin, M A; Stodden, David F; Fischman, Mark G; Weimar, Wendi H

    2011-01-01

    Impulse-variability theory (R. A. Schmidt, H. N. Zelaznik, B. Hawkins, J. S. Frank, & J. T. Quinn, 1979) accounts for the curvilinear relationship between the magnitude and resulting variability of the muscular forces that influence the success of goal-directed limb movements. The historical roots of impulse-variability theory are reviewed in the 1st part of this article, including the relationship between movement speed and spatial error. The authors then address the relevance of impulse-variability theory for the control of ballistic, multijoint skills, such as throwing, striking, and kicking. These types of skills provide a stark contrast to the relatively simple, minimal degrees of freedom movements that characterized early research. However, the inherent demand for ballistic force generation is a strong parallel between these simple laboratory tasks and multijoint motor skills. Therefore, the authors conclude by recommending experimental procedures for evaluating the adequacy of impulse variability as a theoretical model within the context of ballistic, multijoint motor skill performance. Copyright © Taylor & Francis Group, LLC

  3. Potential Use in Forensics of a Novel Hybrid Gelatin-Dynamic Impact Assessment.

    PubMed

    Zecheru, Teodora; Dena, Alexandru; Cîrmaci, Marius; Său, Ciprian; Zaharia, Cătălin; Lăzăroaie, Claudiu

    2018-05-01

    Ballistic gelatin as simulant of the human body and organs is a support in forensics. After having obtained very good results for a new gelatin-based composite in terms of physicochemical and rheological properties, this study focused on this material's mechanical behavior during stabbing and shooting versus bovine and porcine organs and standard ballistic gelatin. The hybrid gelatin has a predominantly elastic behavior at 23°C, whereas the elastic modulus becomes practically constant in the 10-0.1 Hz frequency range. In terms of stabbing behavior, the small variations obtained between porcine organs and surrogate are below 5%, the perforation indicating a good similarity. From the ballistic test results using 10 × 28T rubber balls, it has been seen that the hybrid ballistic gelatin conducts to more reliable and reproducible values of perforation/penetration versus standard gelatin, making from it a real candidate for use in forensic tests. © 2017 American Academy of Forensic Sciences.

  4. Current Testing Capabilities at the NASA Ames Ballistic Ranges

    NASA Technical Reports Server (NTRS)

    Ramsey, Alvin; Tam, Tim; Bogdanoff, David; Gage, Peter

    1999-01-01

    Capabilities for designing and performing ballistic range tests at the NASA Ames Research Center are presented. Computational tools to assist in designing and developing ballistic range models and to predict the flight characteristics of these models are described. A CFD code modeling two-stage gun performance is available, allowing muzzle velocity, maximum projectile base pressure, and gun erosion to be predicted. Aerodynamic characteristics such as drag and stability can be obtained at speeds ranging from 0.2 km/s to 8 km/s. The composition and density of the test gas can be controlled, which allows for an assessment of Reynolds number and specific heat ratio effects under conditions that closely match those encountered during planetary entry. Pressure transducers have been installed in the gun breech to record the time history of the pressure during launch, and pressure transducers have also been installed in the walls of the range to measure sonic boom effects. To illustrate the testing capabilities of the Ames ballistic ranges, an overview of some of the recent tests is given.

  5. The impact of defect scattering on the quasi-ballistic transport of nanoscale conductors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Esqueda, I. S., E-mail: isanchez@isi.edu; Fritze, M.; Cress, C. D.

    2015-02-28

    Using the Landauer approach for carrier transport, we analyze the impact of defects induced by ion irradiation on the transport properties of nanoscale conductors that operate in the quasi-ballistic regime. Degradation of conductance results from a reduction of carrier mean free path due to the introduction of defects in the conducting channel. We incorporate scattering mechanisms from radiation-induced defects into calculations of the transmission coefficient and present a technique for extracting modeling parameters from near-equilibrium transport measurements. These parameters are used to describe degradation in the transport properties of nanoscale devices using a formalism that is valid under quasi-ballistic operation.more » The analysis includes the effects of bandstructure and dimensionality on the impact of defect scattering and discusses transport properties of nanoscale devices from the diffusive to the ballistic limit. We compare calculations with recently published measurements of irradiated nanoscale devices such as single-walled carbon nanotubes, graphene, and deep-submicron Si metal-oxide-semiconductor field-effect transistors.« less

  6. Mallow Fiber-Reinforced Epoxy Composites in Multilayered Armor for Personal Ballistic Protection

    NASA Astrophysics Data System (ADS)

    Nascimento, Lucio Fábio Cassiano; Louro, Luis Henrique Leme; Monteiro, Sergio Neves; Lima, Édio Pereira; da Luz, Fernanda Santos

    2017-10-01

    Lighter and less expensive polymer composites reinforced with natural fibers have been investigated as possible components of a multilayered armor system (MAS) for personal protection against high-velocity ammunition. Their ballistic performance was consistently found comparable with that of conventional Kevlar® synthetic aramid fiber. Among the numerous existing natural fibers with the potential for reinforcing polymer composites to replace Kevlar® in MAS, mallow fiber has not been fully investigated. Thus, the objective of this work is to evaluate the ballistic performance of epoxy composites reinforced with 30 vol.% of aligned mallow fibers as a second MAS layer backing a front ceramic plate. The results using high-velocity 7.62 ammunition show a similar indentation to a Kevlar® layer with the same thickness. An impedance matching calculation supports the similar ballistic performance of mallow fiber composite and Kevlar®. Reduced MAS costs associated with the mallow fiber composite are practical advantages over Kevlar®.

  7. Exact harmonic solutions to Guyer-Krumhansl-type equation and application to heat transport in thin films

    NASA Astrophysics Data System (ADS)

    Zhukovsky, K.; Oskolkov, D.

    2018-03-01

    A system of hyperbolic-type inhomogeneous differential equations (DE) is considered for non-Fourier heat transfer in thin films. Exact harmonic solutions to Guyer-Krumhansl-type heat equation and to the system of inhomogeneous DE are obtained in Cauchy- and Dirichlet-type conditions. The contribution of the ballistic-type heat transport, of the Cattaneo heat waves and of the Fourier heat diffusion is discussed and compared with each other in various conditions. The application of the study to the ballistic heat transport in thin films is performed. Rapid evolution of the ballistic quasi-temperature component in low-dimensional systems is elucidated and compared with slow evolution of its diffusive counterpart. The effect of the ballistic quasi-temperature component on the evolution of the complete quasi-temperature is explored. In this context, the influence of the Knudsen number and of Cauchy- and Dirichlet-type conditions on the evolution of the temperature distribution is explored. The comparative analysis of the obtained solutions is performed.

  8. Effects of Strength vs. Ballistic-Power Training on Throwing Performance

    PubMed Central

    Zaras, Nikolaos; Spengos, Konstantinos; Methenitis, Spyridon; Papadopoulos, Constantinos; Karampatsos, Giorgos; Georgiadis, Giorgos; Stasinaki, Aggeliki; Manta, Panagiota; Terzis, Gerasimos

    2013-01-01

    The purpose of the present study was to investigate the effects of 6 weeks strength vs. ballistic-power (Power) training on shot put throwing performance in novice throwers. Seventeen novice male shot-put throwers were divided into Strength (N = 9) and Power (n = 8) groups. The following measurements were performed before and after the training period: shot put throws, jumping performance (CMJ), Wingate anaerobic performance, 1RM strength, ballistic throws and evaluation of architectural and morphological characteristics of vastus lateralis. Throwing performance increased significantly but similarly after Strength and Power training (7.0-13.5% vs. 6.0-11.5%, respectively). Muscular strength in leg press increased more after Strength than after Power training (43% vs. 21%, respectively), while Power training induced an 8.5% increase in CMJ performance and 9.0 - 25.8% in ballistic throws. Peak power during the Wingate test increased similarly after Strength and Power training. Muscle thickness increased only after Strength training (10%, p < 0.05). Muscle fibre Cross Sectional Area (fCSA) increased in all fibre types after Strength training by 19-26% (p < 0.05), while only type IIx fibres hypertrophied significantly after Power training. Type IIx fibres (%) decreased after Strength but not after Power training. These results suggest that shot put throwing performance can be increased similarly after six weeks of either strength or ballistic power training in novice throwers, but with dissimilar muscular adaptations. Key points Ballistic-power training with 30% of 1RM is equally effective in increasing shot put performance as strength training, in novice throwers, during a short training cycle of six weeks. In novice shot putters with relatively low initial muscle strength/mass, short-term strength training might be more important since it can increase both muscle strength and shot put performance. The ballistic type of power training resulted in a significant increase of the mass of type IIx muscle fibres and no change in their proportion. Thus, this type of training might be used effectively during the last weeks before competition, when the strength training load is usually reduced, in order to increase muscle power and shot put performance in novice shot putters. PMID:24149736

  9. Effects of Different Relative Loads on Power Performance During the Ballistic Push-up.

    PubMed

    Wang, Ran; Hoffman, Jay R; Sadres, Eliahu; Bartolomei, Sandro; Muddle, Tyler W D; Fukuda, David H; Stout, Jeffrey R

    2017-12-01

    Wang, R, Hoffman, JR, Sadres, E, Bartolomei, S, Muddle, TWD, Fukuda, DH, and Stout, JR. Effects of different relative loads on power performance during the ballistic push-up. J Strength Cond Res 31(12): 3411-3416, 2017-The purpose of this investigation was to examine the effect of load on force and power performance during a ballistic push-up. Sixty (24.5 ± 4.3 years, 1.75 ± 0.07 m, and 80.8 ± 13.5 kg) recreationally active men who participated in this investigation completed all testing and were included in the data analysis. All participants were required to perform a 1 repetition maximum bench press, and ballistic push-ups without external load (T1), with 10% (T2) and 20% (T3) of their body mass. Ballistic push-ups during T2 and T3 were performed using a weight loaded vest. Peak and mean force, power, as well as net impulse and flight time were determined for each ballistic push-up. Peak and mean force were both significantly greater (p < 0.01) during T3 (1,062 ± 202 and 901 ± 154 N, respectively), than both T2 (1,017 ± 202 and 842 ± 151 N, respectively) and T1 (960 ± 188 and 792 ± 140 N, respectively). Peak and mean power were significantly greater (p < 0.01) during T1 (950 ± 257 and 521 ± 148 W, respectively), than both T2 (872 ± 246 and 485 ± 143 W, respectively) and T3 (814 ± 275 and 485 ± 162 W, respectively). Peak and mean power were greatest during T1, regardless of participants' strength levels. Significant (p < 0.01) greater net impulse and smaller peak velocity and flight time were also noted from T1 to T3. Results of this investigation indicated that maximal power outputs were achieved without the use of an external load when performing the ballistic push-up, regardless of the participants' level of strength.

  10. Effects of Strength vs. Ballistic-Power Training on Throwing Performance.

    PubMed

    Zaras, Nikolaos; Spengos, Konstantinos; Methenitis, Spyridon; Papadopoulos, Constantinos; Karampatsos, Giorgos; Georgiadis, Giorgos; Stasinaki, Aggeliki; Manta, Panagiota; Terzis, Gerasimos

    2013-01-01

    The purpose of the present study was to investigate the effects of 6 weeks strength vs. ballistic-power (Power) training on shot put throwing performance in novice throwers. Seventeen novice male shot-put throwers were divided into Strength (N = 9) and Power (n = 8) groups. The following measurements were performed before and after the training period: shot put throws, jumping performance (CMJ), Wingate anaerobic performance, 1RM strength, ballistic throws and evaluation of architectural and morphological characteristics of vastus lateralis. Throwing performance increased significantly but similarly after Strength and Power training (7.0-13.5% vs. 6.0-11.5%, respectively). Muscular strength in leg press increased more after Strength than after Power training (43% vs. 21%, respectively), while Power training induced an 8.5% increase in CMJ performance and 9.0 - 25.8% in ballistic throws. Peak power during the Wingate test increased similarly after Strength and Power training. Muscle thickness increased only after Strength training (10%, p < 0.05). Muscle fibre Cross Sectional Area (fCSA) increased in all fibre types after Strength training by 19-26% (p < 0.05), while only type IIx fibres hypertrophied significantly after Power training. Type IIx fibres (%) decreased after Strength but not after Power training. These results suggest that shot put throwing performance can be increased similarly after six weeks of either strength or ballistic power training in novice throwers, but with dissimilar muscular adaptations. Key pointsBallistic-power training with 30% of 1RM is equally effective in increasing shot put performance as strength training, in novice throwers, during a short training cycle of six weeks.In novice shot putters with relatively low initial muscle strength/mass, short-term strength training might be more important since it can increase both muscle strength and shot put performance.The ballistic type of power training resulted in a significant increase of the mass of type IIx muscle fibres and no change in their proportion. Thus, this type of training might be used effectively during the last weeks before competition, when the strength training load is usually reduced, in order to increase muscle power and shot put performance in novice shot putters.

  11. Orion Parachute Riser Cutter Development

    NASA Technical Reports Server (NTRS)

    Oguz, Sirri; Salazar, Frank

    2011-01-01

    This paper presents the tests and analytical approach used on the development of a steel riser cutter for the CEV Parachute Assembly System (CPAS) used on the Orion crew module. Figure 1 shows the riser cutter and the steel riser bundle which consists of six individual cables. Due to the highly compressed schedule, initial unavailability of the riser material and the Orion Forward Bay mechanical constraints, JSC primarily relied on a combination of internal ballistics analysis and LS-DYNA simulation for this project. Various one dimensional internal ballistics codes that use standard equation of state and conservation of energy have commonly used in the development of CAD devices for initial first order estimates and as an enhancement to the test program. While these codes are very accurate for propellant performance prediction, they usually lack a fully defined kinematic model for dynamic predictions. A simple piston device can easily and accurately be modeled using an equation of motion. However, the accuracy of analytical models is greatly reduced on more complicated devices with complex external loads, nonlinear trajectories or unique unlocking features. A 3D finite element model of CAD device with all critical features included can vastly improve the analytical ballistic predictions when it is used as a supplement to the ballistic code. During this project, LS-DYNA structural 3D model was used to predict the riser resisting load that was needed for the ballistic code. A Lagrangian model with eroding elements shown in Figure 2 was used for the blade, steel riser and the anvil. The riser material failure strain was fine tuned by matching the dent depth on the anvil with the actual test data. LS-DYNA model was also utilized to optimize the blade tip design for the most efficient cut. In parallel, the propellant type and the amount were determined by using CADPROG internal ballistics code. Initial test results showed a good match with LS-DYNA and CADPROG simulations. Final paper will present a detailed roadmap from initial ballistic modeling and LS-DYNA simulation to the performance testing. Blade shape optimization study will also be presented.

  12. Examples of the nonlinear dynamics of ballistic capture and escape in the earth-moon system

    NASA Technical Reports Server (NTRS)

    Belbruno, Edward A.

    1990-01-01

    An example of a trajectory is given which is initially captured in an elliptic resonant orbit about the earth and then ballistically escapes the earth-moon system. This is demonstrated by a numerical example in three-dimensions using a planetary ephemeris. Another example shows a mechanism of how an elliptic orbit about the earth can increase its energy by performing a complex nonlinear transition to an elliptic orbit of a larger semi-major axis. Capture is also considered. An application of ballistic capture at the moon via an unstable periodic orbit using the four-body sun-earth-moon-S/C interaction is described.

  13. Low-Energy Ballistic Transfers to Lunar Halo Orbits

    NASA Technical Reports Server (NTRS)

    Parker, Jeffrey S.

    2009-01-01

    Recent lunar missions have begun to take advantage of the benefits of low-energy ballistic transfers between the Earth and the Moon rather than implementing conventional Hohmann-like lunar transfers. Both Artemis and GRAIL plan to implement low-energy lunar transfers in the next few years. This paper explores the characteristics and potential applications of many different families of low-energy ballistic lunar transfers. The transfers presented here begin from a wide variety of different orbits at the Earth and follow several different distinct pathways to the Moon. This paper characterizes these pathways to identify desirable low-energy lunar transfers for future lunar missions.

  14. An experimental study of the self-healing behavior of ionomeric systems under ballistic impact tests

    NASA Astrophysics Data System (ADS)

    Grande, A. M.; Coppi, S.; Di Landro, L.; Sala, G.; Giacomuzzo, C.; Francesconi, A.; Rahman, M. A.

    2012-04-01

    This research deals with the investigation of the self-healing behavior after ballistic damage of ethylene-methacrylic acid ionomers and theirs blends with epoxidized natural rubber (ENR). The self-healing capability was studied by ballistic puncture tests under different experimental conditions as sample thickness, bullet speed, diameter and shape. Bullet speed ranging from few hundreds meters per second to few km/s were employed. The healing efficiency was evaluated by applying a pressure gradient trough the plates and by checking for possible flow at the damage zone. A morphology analysis of the impact area was made observing all samples by scanning electron microscope.

  15. Fabrication and testing of prestressed composite rotor blade spar specimens

    NASA Technical Reports Server (NTRS)

    Gleich, D.

    1974-01-01

    Prestressed composite spar specimens were fabricated and evaluated by crack propagation and ballistic penetration tests. The crack propagation tests on flawed specimens showed that the prestressed composite spar construction significantly suppresses crack growth. Damage from three high velocity 30 caliber projectile hits was confined to three small holes in the ballistic test specimen. No fragmentation or crack propagation was observed indicating good ballistic damage resistance. Rotor attachment approaches and improved structural performance configurations were identified. Design theory was verified by tests. The prestressed composite spar configuration consisted of a compressively prestressed high strength ARDEFORM 301 stainless steel liner overwrapped with pretensioned S-994 fiberglass.

  16. Solution of internal ballistic problem for SRM with grain of complex shape during main firing phase

    NASA Astrophysics Data System (ADS)

    Kiryushkin, A. E.; Minkov, L. L.

    2017-10-01

    Solid rocket motor (SRM) internal ballistics problems are related to the problems with moving boundaries. The algorithm able to solve similar problems in axisymmetric formulation on Cartesian mesh with an arbitrary order of accuracy is considered in this paper. The base of this algorithm is the ghost point extrapolation using inverse Lax-Wendroff procedure. Level set method is used as an implicit representation of the domain boundary. As an example, the internal ballistics problem for SRM with umbrella type grain was solved during the main firing phase. In addition, flow parameters distribution in the combustion chamber was obtained for different time moments.

  17. Field surgery on a future conventional battlefield: strategy and wound management.

    PubMed Central

    Ryan, J. M.; Cooper, G. J.; Haywood, I. R.; Milner, S. M.

    1991-01-01

    Most papers appearing in the surgical literature dealing with wound ballistics concern themselves with wound management in the civilian setting. The pathophysiology of modern war wounds is contrasted with ballistic wounds commonly encountered in peacetime, but it should be noted that even in peacetime the modern terrorist may have access to sophisticated military weaponry, and that patients injured by them may fall within the catchment area of any civilian hospital. Management problems associated with both wound types are highlighted; areas of controversy are discussed. The orthodox military surgical approach to ballistic wounds is expounded and defended. Images Figure 2 Figure Figure 4 PMID:1996857

  18. Ballistic missile precession frequency extraction by spectrogram's texture

    NASA Astrophysics Data System (ADS)

    Wu, Longlong; Xu, Shiyou; Li, Gang; Chen, Zengping

    2013-10-01

    In order to extract precession frequency, an crucial parameter in ballistic target recognition, which reflected the kinematical characteristics as well as structural and mass distribution features, we developed a dynamic RCS signal model for a conical ballistic missile warhead, with a log-norm multiplicative noise, substituting the familiar additive noise, derived formulas of micro-Doppler induced by precession motion, and analyzed time-varying micro-Doppler features utilizing time-frequency transforms, extracted precession frequency by measuring the spectrogram's texture, verified them by computer simulation studies. Simulation demonstrates the excellent performance of the method proposed in extracting the precession frequency, especially in the case of low SNR.

  19. Evolution of Structure and Composition in Saturn's Rings Due to Ballistic Transport of Micrometeoroid Impact Ejecta

    NASA Astrophysics Data System (ADS)

    Estrada, P. R.; Durisen, R. H.; Cuzzi, J. N.

    2014-04-01

    We introduce improved numerical techniques for simulating the structural and compositional evolution of planetary rings due to micrometeoroid bombardment and subsequent ballistic transport of impact ejecta. Our current, robust code, which is based on the original structural code of [1] and on the pollution transport code of [3], is capable of modeling structural changes and pollution transport simultaneously over long times on both local and global scales. We provide demonstrative simulations to compare with, and extend upon previous work, as well as examples of how ballistic transport can maintain the observed structure in Saturn's rings using available Cassini occultation optical depth data.

  20. Multi-Fiber Composites

    NASA Technical Reports Server (NTRS)

    Novak, R. C.

    1976-01-01

    Resin matrix composites having improved resistance to foreign object damage in gas turbine engine fan blade applications were developed. Materials evaluated include epoxy matrix graphite/glass and boron/glass hybrids, thermoplastic matrix boron/glass hybrids, and superhybrids consisting of graphite/epoxy, boron/aluminum, and titanium alloy sheets. Static, pendulum impact, and ballistic impact test results are reported for all materials. Superhybrid blade like specimens are shown to be capable of withstanding relatively severe ballistic impacts from gelatin spheres without fracture. The effects of ply configuration and projectile angle of incidence on impact behavior are described. Predictions of surface strains during ballistic impact are presented and shown to be in reasonable agreement with experimental measurements.

  1. Acoustic ranging of small arms fire using a single sensor node collocated with the target.

    PubMed

    Lo, Kam W; Ferguson, Brian G

    2015-06-01

    A ballistic model-based method, which builds upon previous work by Lo and Ferguson [J. Acoust. Soc. Am. 132, 2997-3017 (2012)], is described for ranging small arms fire using a single acoustic sensor node collocated with the target, without a priori knowledge of the muzzle speed and ballistic constant of the bullet except that they belong to a known two-dimensional parameter space. The method requires measurements of the differential time of arrival and differential angle of arrival of the muzzle blast and ballistic shock wave at the sensor node. Its performance is evaluated using both simulated and real data.

  2. Ballistic phonon transmission in quasiperiodic acoustic nanocavities

    NASA Astrophysics Data System (ADS)

    Mo, Yuan; Huang, Wei-Qing; Huang, Gui-Fang; Chen, Yuan; Hu, Wangyu; Wang, Ling-Ling; Pan, Anlian

    2011-04-01

    Ballistic phonon transport is investigated in acoustic nanocavities modulated in a quasiperiodic manner at low temperatures. Two different types of quasiperiodic acoustic nanocavities are considered: the lengths of nanocavities (QPL) and the lengths of the bridges (QPD) connecting two successive nanocavities are modulated according to the Fibonacci rule. We demonstrate that the transmission spectra and thermal conductance in both systems are similar, which is more prominent in QPD than in QPL. The transmission and thermal conductance of QPD are larger than those of QPL due to the fact that constant nanocavity length in QPD would strengthen ballistic phonon resonant transport, while varying nanocavity length in QPL lead to strong phonon scattering.

  3. The Ballistic Cart on an Incline Revisited.

    ERIC Educational Resources Information Center

    Serway, Raymond A.; And Others

    1995-01-01

    Presents the theory behind the mechanics demonstration that involves projecting a ball vertically upward from a ballistic cart moving along an inclined plane. The measured overshoot is believed to be due, in part, to the presence of rolling friction and the inertial properties of the cart wheels. (JRH)

  4. 76 FR 27355 - 2011 National Institute of Justice Body Armor Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-11

    ... Institute of Justice Body Armor Workshop AGENCY: National Institute of Justice, DOJ. ACTION: Notice of Meeting of the 2011 NIJ Body Armor Workshop. SUMMARY: The National Institute of Justice invites manufacturers of ballistic-resistant body armor, ballistic laboratory testing facilities and other interested...

  5. The quantified evaluation of the wounding potential of a ricochet projectile of a handgun cartridge calibre 9 mm (type 82) in a ballistic experiment.

    PubMed

    Moravanský, Norbert; Rekeň, Viktor; Juříček, Ludvík; Zummerová, Anežka; Kováč, Peter

    2013-01-01

    The question of handgun use in a city or densely populated aglomerations requires a highly practical level of solution to this issue, though with the knowledge of theoretical presumptions of wound ballistics of ricochet projectiles. The application of wound ballistics into the practice of a forensic pathologist, as well as a surgeon or a traumatologist, enables a good understanding of the dynamics of projectile penetration through anatomic structures of the human body. In forensic assessment, gunshot wounds of limbs are relatively frequent cases. By the integration of wound ballistics principles into the research of gunshot wounds, it is also possible to establish, whether the projectile entered into the anatomic structures under direct trajectory steadily or whether through the course of its trajectory, before reaching the human body, it firstly contacted a particular object in the space, i. e. whether the injury could have been caused by a ricochet projectile. In connection with unclear gunshot wounds and their morphological image, it is necessary to consider the possibility of the effects of a ricochet projectile, especially when persons are injured accidentally. The daily practice of the officers of the Police Corps of the Slovak Republic essentially enhances the necessity of being informed about the behaviour of parametrically designated ricochet projectiles in a ballistic experiment with the use of a model of a built-up area in a town, with typical materials and surfaces of objects in between and a model of a human limb part as a potential target of an uncontrolled ricochet projectile. The proposed design of the situation is undoubtedly of an enormous significance, even when forensically evaluating the morphological consequences of ricochet projectiles. By the application of results of such experiments and their final comparison, when different types of projectiles are used, it is also possible to contribute to the experts groundwork in the process of rearmament of the official armed forces. The main aim of our work is to point out the high potential of the wounding effect of ricochet bullets of a particular calibre cartridge with focus on injuries of the femurs of the lower limbs. The carried out ballistic experiment was designed for the needs of the experimental part of a diploma thesis of a student from the Faculty of Medicine of Comenius University in Bratislava and his results point out at the possibilities for civilian safety strategies during the intervention of the armed forces as well. Terminal ballistics - Ballistic experiment - Ricochet projectile - Gunshot wounds.

  6. Medical Provider Ballistic Protection at Active Shooter Events.

    PubMed

    Stopyra, Jason P; Bozeman, William P; Callaway, David W; Winslow, James; McGinnis, Henderson D; Sempsrott, Justin; Evans-Taylor, Lisa; Alson, Roy L

    2016-01-01

    There is some controversy about whether ballistic protective equipment (body armor) is required for medical responders who may be called to respond to active shooter mass casualty incidents. In this article, we describe the ongoing evolution of recommendations to optimize medical care to injured victims at such an incident. We propose that body armor is not mandatory for medical responders participating in a rapid-response capacity, in keeping with the Hartford Consensus and Arlington Rescue Task Force models. However, we acknowledge that the development and implementation of these programs may benefit from the availability of such equipment as one component of risk mitigation. Many police agencies regularly retire body armor on a defined time schedule before the end of its effective service life. Coordination with law enforcement may allow such retired body armor to be available to other public safety agencies, such as fire and emergency medical services, providing some degree of ballistic protection to medical responders at little or no cost during the rare mass casualty incident. To provide visual demonstration of this concept, we tested three "retired" ballistic vests with ages ranging from 6 to 27 years. The vests were shot at close range using police-issue 9mm, .40 caliber, .45 caliber, and 12-gauge shotgun rounds. Photographs demonstrate that the vests maintained their ballistic protection and defeated all of these rounds. 2016.

  7. Ballistic tongue projection in a miniaturized salamander.

    PubMed

    Deban, Stephen M; Bloom, Segall V

    2018-05-20

    Miniaturization of body size is often accompanied by peculiarities in morphology that can have functional consequences. We examined the feeding behavior and morphology of the miniaturized plethodontid salamander Thorius, one of the smallest vertebrates, to determine if its performance and biomechanics differ from those of its larger relatives. High-speed imaging and dynamics analysis of feeding at a range of temperatures show that tongue projection in Thorius macdougalli is ballistic and achieves accelerations of up to 600 G with low thermal sensitivity, indicating that tongue projection is powered by an elastic-recoil mechanism. Preceding ballistic projection is an unusual preparatory phase of tongue protrusion, which, like tongue retraction, shows lower performance and higher thermal sensitivity that are indicative of movement being powered directly by muscle shortening. The variability of tongue-projection kinematics and dynamics is comparable to larger ballistic-tongued plethodontids and reveals that Thorius is capable of modulating its tongue movements in response to prey distance. Morphological examination revealed that T. macdougalli possesses a reduced number of myofibers in the tongue muscles, a large projector muscle mass relative to tongue mass, and an unusual folding of the tongue skeleton, compared with larger relatives. Nonetheless, T. macdougalli retains the elaborated collagen aponeuroses in the projector muscle that store elastic energy and a tongue skeleton that is free of direct myofiber insertion, two features that appear to be essential for ballistic tongue projection in salamanders. © 2018 Wiley Periodicals, Inc.

  8. Comparison of ballistic impact effects between biological tissue and gelatin.

    PubMed

    Jin, Yongxi; Mai, Ruimin; Wu, Cheng; Han, Ruiguo; Li, Bingcang

    2018-02-01

    Gelatin is commonly used in ballistic testing as substitute for biological tissue. Comparison of ballistic impact effects produced in the gelatin and living tissue is lacking. The work in this paper was aimed to compare the typical ballistic impact effects (penetration trajectory, energy transfer, temporary cavity) caused by 4.8mm steel ball penetrating the 60kg porcine hind limbs and 10wt% gelatin. The impact event in the biological tissue was recorded by high speed flash X-ray machine at different delay time, while the event in the gelatin continuously recorded by high speed video was compared to that in the biological tissue. The collected results clearly displayed that the ballistic impact effects in the muscle and gelatin were similar for the steel ball test; as for instance, the projectile trajectory in the two targets was basically similar, the process of energy transfer was highly coincident, and the expansion of temporary cavity followed the same pattern. This study fully demonstrated that choosing gelatin as muscle simulant was reasonable. However, the maximum temporary cavity diameter in the gelatin was a little larger than that in the muscle, and the expansion period of temporary cavity was longer in the gelatin. Additionally, the temporary cavity collapse process in the two targets followed different patterns, and the collapse period in the gelatin was two times as long as that in the muscle. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Determine ISS Soyuz Orbital Module Ballistic Limits for Steel Projectiles Hypervelocity Impact Testing

    NASA Technical Reports Server (NTRS)

    Lyons, Frankel

    2013-01-01

    A new orbital debris environment model (ORDEM 3.0) defines the density distribution of the debris environment in terms of the fraction of debris that are low-density (plastic), medium-density (aluminum) or high-density (steel) particles. This hypervelocity impact (HVI) program focused on assessing ballistic limits (BLs) for steel projectiles impacting the enhanced Soyuz Orbital Module (OM) micrometeoroid and orbital debris (MMOD) shield configuration. The ballistic limit was defined as the projectile size on the threshold of failure of the OM pressure shell as a function of impact speeds and angle. The enhanced OM shield configuration was first introduced with Soyuz 30S (launched in May 2012) to improve the MMOD protection of Soyuz vehicles docked to the International Space Station (ISS). This test program provides HVI data on U.S. materials similar in composition and density to the Russian materials for the enhanced Soyuz OM shield configuration of the vehicle. Data from this test program was used to update ballistic limit equations used in Soyuz OM penetration risk assessments. The objective of this hypervelocity impact test program was to determine the ballistic limit particle size for 440C stainless steel spherical projectiles on the Soyuz OM shielding at several impact conditions (velocity and angle combinations). This test report was prepared by NASA-JSC/ HVIT, upon completion of tests.

  10. The Effect of Ballistic Impacts on the High Cycle Fatigue Properties of Ti-48Al-2Nb-2Cr (at.%)

    NASA Technical Reports Server (NTRS)

    Draper, S. L.; Lerch, B. A.; Pereira, J. M.; Nathal, M. V.; Austin, C. M.; Erdman, O.

    2000-01-01

    The ability of gamma - TiAl to withstand potential foreign and/or domestic object damage is a technical risk to the implementation of gamma - TiAl in low pressure turbine (LPT) blade applications. The overall purpose of the present study was to determine the influence of ballistic impact damage on the high cycle fatigue strength of gamma - TiAl simulated LPT blades. Impact and specimen variables included ballistic impact energy, projectile hardness, impact temperature, impact location, and leading edge thickness. The level of damage induced by the ballistic impacting was studied and quantified on both the impact (front) and backside of the specimens. Multiple linear regression was used to model the cracking and fatigue response as a function of the impact variables. Of the impact variables studied, impact energy had the largest influence on the response of gamma - TiAl to ballistic impacting. Backside crack length was the best predictor of remnant fatigue strength for low energy impacts (<0.74J) whereas Hertzian crack length (impact side damage) was the best predictor for higher energy impacts. The impacted gamma - TiAl samples displayed a classical mean stress dependence on the fatigue strength. For the fatigue design stresses of a 6th stage LPT blade in a GE90 engine, a Ti-48Al-2Nb-2Cr LPT blade would survive an impact of normal service conditions.

  11. U.S. Air Force Aircrew Flight Protective Eyewear Program

    DTIC Science & Technology

    2013-02-01

    MIL-DTL-32000), fire - resistant hydraulic fluid (MIL-PRF-46170), petroleum-based hydraulic fluid (MIL-PRF-6083), gasoline (87% octane), motor oil...UPLC installed. ABRASION FPE spectacles and goggles shall maximize resistance to scratching/ abrasion to minimize interference with vision...Visual Area ................................................................................. 2 3.0 BALLISTIC AND IMPACT RESISTANCE : BALLISTIC

  12. The mechanism for explosive seed dispersal in Cardamine hirsuta (Brassicceae)

    USDA-ARS?s Scientific Manuscript database

    Many highly successful weed species have the ability to disperse their propagules through the ballistic discharge of their seeds either at ripening or when disturbed by an herbivore. However, very little is known of how ballistic seed dispersal is achieved. Bittercress (Cardamine hirsuta L.) is a we...

  13. Pointing and Voicing in Deictic Expressions.

    ERIC Educational Resources Information Center

    Levelt, Willem J. M.; And Others

    1985-01-01

    Describes a study of how the interdependence of speech and gesture is realized in the course of motor planning and execution. Do the two systems operate interactively or do they operate in a ballistic or independent fashion? Four experiments showed that, for deictic expressions, the ballistic view is very nearly correct. (SED)

  14. 76 FR 30986 - Bureau of International Security and Nonproliferation; Imposition of Nonproliferation Measures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-27

    ... control lists (Missile Technology Control Regime, Australia Group, Chemical Weapons Convention, Nuclear... the development of weapons of mass destruction (WMD) or cruise or ballistic missile systems. The... contribution to WMD or cruise or ballistic missile systems, (b) other items with the potential of making such a...

  15. 75 FR 40862 - Bureau of Verification, Compliance, and Implementation; Imposition of Sanctions Against Foreign...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ... (Missile Technology Control Regime, Australia Group, Chemical Weapons Convention, Nuclear Suppliers Group... of weapons of mass destruction (WMD) or cruise or ballistic missile systems. The latter category... or cruise or ballistic missile systems, (b) other items with the potential of making such a material...

  16. 78 FR 6765 - Amendment to the International Traffic in Arms Regulations: Revision of U.S. Munitions List...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-31

    ... revise Category IV (launch vehicles, guided missiles, ballistic missiles, rockets, torpedoes, bombs, and... revises USML Category IV (launch vehicles, guided missiles, ballistic missiles, rockets, torpedoes, bombs... missiles, rockets, torpedoes, bombs, and mines whose jurisdiction would be in doubt based on this revision...

  17. Science aspects of 1980 ballistic missions to comet Encke, using Mariner and Pioneer spacecraft

    NASA Technical Reports Server (NTRS)

    Jaffe, L. D.; Elachi, C.; Giffin, C. E.; Huntress, W.; Newburn, R. L., Jr.; Parker, R. H.; Taylor, F. W.; Thorpe, T. E.

    1976-01-01

    Science aspects of a 1980 spacecraft reconnaissance of Comet Encke are considered. The mission discussed is a ballistic flyby (more exactly, a fly-through) of P/Encke, using either a spin stabilized spacecraft, without despin of instruments, or a 3-axis stabilized spacecraft.

  18. 28 CFR 16.98 - Exemption of the Drug Enforcement Administration (DEA)-limited access.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (Justice/DEA-013) (7) System to Retrieve Information from Drug Evidence (STRIDE/Ballistics) (Justice/DEA... Retrieve Information from Drug Evidence (STRIDE/Ballistics) (Justice/DEA-014) only to the extent that..., implemented internal quality assurance procedures to ensure that ESS data is as thorough, accurate, and...

  19. 28 CFR 16.98 - Exemption of the Drug Enforcement Administration (DEA)-limited access.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (Justice/DEA-013) (7) System to Retrieve Information from Drug Evidence (STRIDE/Ballistics) (Justice/DEA... Retrieve Information from Drug Evidence (STRIDE/Ballistics) (Justice/DEA-014) only to the extent that..., implemented internal quality assurance procedures to ensure that ESS data is as thorough, accurate, and...

  20. Expected scientific results on ballistic spacecraft missions to comet Encke during the 1980 apparition

    NASA Technical Reports Server (NTRS)

    Mumma, M. J.

    1976-01-01

    Summarized are three proposed ballistic spacecraft missions to intercept P/Encke during the 1980 apparition. A baseline physical activity model for P/Encke is established and the performances of the neutral mass spectrometer and of the imaging experiment on each intercept mission are assessed.

  1. 77 FR 6548 - Notice of Availability of Ballistic Survivability, Lethality and Vulnerability Analyses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-08

    ..., Lethality and Vulnerability Analyses AGENCY: Department of the Army, DoD. ACTION: Notice of availability...) is a leader in ballistic survivability, lethality and vulnerability (SLV) analyses. ARL/SLAD conducts SLV analyses, using the MUVES-S2 vulnerability model, to quantify system, subsystem and/or component...

  2. Dynamic CFD Simulations of the Supersonic Inflatable Aerodynamic Decelerator (SIAD) Ballistic Range Tests

    NASA Technical Reports Server (NTRS)

    Brock, Joseph M; Stern, Eric

    2016-01-01

    Dynamic CFD simulations of the SIAD ballistic test model were performed using US3D flow solver. Motivation for performing these simulations is for the purpose of validation and verification of the US3D flow solver as a viable computational tool for predicting dynamic coefficients.

  3. Space shuttle system program definition. Volume 4: Cost and schedule report

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The supporting cost and schedule data for the second half of the Space Shuttle System Phase B Extension Study is summarized. The major objective for this period was to address the cost/schedule differences affecting final selection of the HO orbiter space shuttle system. The contending options under study included the following booster launch configurations: (1) series burn ballistic recoverable booster (BRB), (2) parallel burn ballistic recoverable booster (BRB), (3) series burn solid rocket motors (SRM's), and (4) parallel burn solid rocket motors (SRM's). The implications of varying payload bay sizes for the orbiter, engine type for the ballistics recoverable booster, and SRM motors for the solid booster were examined.

  4. Non-Ballistic Vapor-Driven Ejecta

    NASA Technical Reports Server (NTRS)

    Wrobel, K. E.; Schultz, P. H.; Heineck, J. T.

    2004-01-01

    Impact-induced vaporization is a key component of early-time cratering mechanics. Previous experimental [1,2] and computational [e.g., 3] studies focused on the generation and expansion of vapor clouds in an attempt to better understand vaporization in hypervelocity impacts. Presented here is a new experimental approach to the study of impact-induced vaporization. The three-dimensional particle image velocimetry (3D PIV) system captures interactions between expanding vapor phases and fine particulates. Particles ejected early in the cratering process may be entrained in expanding gas phases generated at impact, altering their otherwise ballistic path of flight. 3D PIV allows identifying the presence of such non-ballistic ejecta from very early times in the cratering process.

  5. [Wound Ballistics – a Brief Overview].

    PubMed

    Bolliger, Stephan A; Eggert, Sebastian; Thali, Michael J

    2016-02-03

    Wound ballistics examines the specific effect, namely the wound profile, of bullets on the body by firing at synthetic models made of ordnance gelatine, glycerin soap and synthetic bones, validated with real cases from (battlefield) surgery and forensic pathology. Wound profile refers to the penetration depth, the bullet deformation/ fragmentation, the diameter of the permanent and the temporary wound cavity. Knowing these features and the used ammunition a surgeon can rapidly assess the amount damage within a patient. The forensic pathologist can draw conclusions as to the used ammunition based on the wound profile. By measuring of the destructive capability of different ammunition types, wound ballistics lays the foundation for guidelines concerning the maximum effect of military ammunition.

  6. One-Dimensional Modelling of Internal Ballistics

    NASA Astrophysics Data System (ADS)

    Monreal-González, G.; Otón-Martínez, R. A.; Velasco, F. J. S.; García-Cascáles, J. R.; Ramírez-Fernández, F. J.

    2017-10-01

    A one-dimensional model is introduced in this paper for problems of internal ballistics involving solid propellant combustion. First, the work presents the physical approach and equations adopted. Closure relationships accounting for the physical phenomena taking place during combustion (interfacial friction, interfacial heat transfer, combustion) are deeply discussed. Secondly, the numerical method proposed is presented. Finally, numerical results provided by this code (UXGun) are compared with results of experimental tests and with the outcome from a well-known zero-dimensional code. The model provides successful results in firing tests of artillery guns, predicting with good accuracy the maximum pressure in the chamber and muzzle velocity what highlights its capabilities as prediction/design tool for internal ballistics.

  7. The effect of hydrogen content on ballistic transport behaviors in the Ni-Nb-Zr-H glassy alloys.

    PubMed

    Fukuhara, Mikio; Umemori, Yoshimasa

    2012-01-01

    The electronic transport behaviors of (Ni(0.39)Nb(0.25)Zr(0.35))(100-) (x)H(x) (0 ≤ x < 23.5) glassy alloys with subnanostructural icosahedral Zr(5)Nb(5)Ni(3) clusters have been studied as a function of hydrogen content. These alloys show semiconducting, electric current-induced voltage (Coulomb) oscillation and ballistic transport behaviors. Coulomb oscillation and ballistic transport occur at hydrogen contents between 6.7 and 13.5 at% and between 13.5 and 21.2 at%, respectively. These results suggest that the localization effect of hydrogen in the clusters plays an important role in various electron transport phenomena.

  8. Numerical modelling of physical processes in a ballistic laboratory setup with a tapered adapter and plastic piston used for obtaining high muzzle velocities

    NASA Astrophysics Data System (ADS)

    Bykov, N. V.

    2014-12-01

    Numerical modelling of a ballistic setup with a tapered adapter and plastic piston is considered. The processes in the firing chamber are described within the framework of quasi- one-dimensional gas dynamics and a geometrical law of propellant burn by means of Lagrangian mass coordinates. The deformable piston is considered to be an ideal liquid with specific equations of state. The numerical solution is obtained by means of a modified explicit von Neumann scheme. The calculation results given show that the ballistic setup with a tapered adapter and plastic piston produces increased shell muzzle velocities by a factor of more than 1.5-2.

  9. The Effect of Hydrogen Content on Ballistic Transport Behaviors in the Ni-Nb-Zr-H Glassy Alloys

    PubMed Central

    Fukuhara, Mikio; Umemori, Yoshimasa

    2012-01-01

    The electronic transport behaviors of (Ni0.39Nb0.25Zr0.35)100−xHx (0 ≤ x < 23.5) glassy alloys with subnanostructural icosahedral Zr5Nb5Ni3 clusters have been studied as a function of hydrogen content. These alloys show semiconducting, electric current-induced voltage (Coulomb) oscillation and ballistic transport behaviors. Coulomb oscillation and ballistic transport occur at hydrogen contents between 6.7 and 13.5 at% and between 13.5 and 21.2 at%, respectively. These results suggest that the localization effect of hydrogen in the clusters plays an important role in various electron transport phenomena. PMID:22312246

  10. Missile injuries in head - neck and maxillo-facial region - an experience in eastern nepal.

    PubMed

    Wakode, P T; Ghimire, Anand; Acharya, Roshan

    2008-06-01

    Ballistic injuries to head-neck and maxillofacial region is quite common problem nowadays. Most of the time the injuries seem to be dreadful but the mechanism of the injuries caused by ballistics and the anatomical conditions of maxillofacial and head-neck region mitigate the severity of the injuries. Proper primary management followed by reconstruction and management of associated injuries decreases the mortality and morbidity of missile injuries in head-neck and maxillofacial region. Eleven cases of missile injuries in head-neck and maxillofacial region are included in the present study. The mechanism of the injury and the ideal management strategy for the ballistics injuries in the region has been discussed in the article.

  11. The Internal Ballistics of an Air Gun

    ERIC Educational Resources Information Center

    Denny, Mark

    2011-01-01

    The internal ballistics of a firearm or artillery piece considers the pellet, bullet, or shell motion while it is still inside the barrel. In general, deriving the muzzle speed of a gunpowder firearm from first principles is difficult because powder combustion is fast and it very rapidly raises the temperature of gas (generated by gunpowder…

  12. Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues

    DTIC Science & Technology

    2016-02-24

    13 The FALCON Study...range strike capabilities. These include bombers, cruise missiles, ballistic missiles, and boost-glide technologies that would mate a rocket booster...Command, Hearing, April 4, 2005. 23 Grossman, Elaine M., “U.S. General: Precise Long-Range Missiles may Enable Big Nuclear Cuts,” Inside the Pentagon

  13. 8 CFR 204.10 - Petitions by, or for, certain scientists of the Commonwealth of Independent States or the Baltic...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... ballistic missiles, nuclear, biological, chemical, or other high-technology weapons of mass destruction, or who are working on nuclear, chemical, biological, or other high-technology defense projects, as... production of ballistic missiles, nuclear, biological, chemical, or other high-technology weapons of mass...

  14. 8 CFR 204.10 - Petitions by, or for, certain scientists of the Commonwealth of Independent States or the Baltic...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ballistic missiles, nuclear, biological, chemical, or other high-technology weapons of mass destruction, or who are working on nuclear, chemical, biological, or other high-technology defense projects, as... production of ballistic missiles, nuclear, biological, chemical, or other high-technology weapons of mass...

  15. Advanced Ceramic Armor Materials

    DTIC Science & Technology

    1990-05-11

    materials, toughened alumina, fiber -reinforced glass matrix composites, and multilayer-gradient materials for ballistic testing. Fabrication and...material systems: Multilayer advanced armor materials consisting of a hard ceramic faceplate bonded to a graphite fiber -reinforced glass matrix...toughened alumina, and fiber - applied studies of advanced reinforced ceramic matrix glass and glass -ceramic composites for ballistic testing. technologies

  16. The Simplest Complete Model of Choice Response Time: Linear Ballistic Accumulation

    ERIC Educational Resources Information Center

    Brown, Scott D.; Heathcote, Andrew

    2008-01-01

    We propose a linear ballistic accumulator (LBA) model of decision making and reaction time. The LBA is simpler than other models of choice response time, with independent accumulators that race towards a common response threshold. Activity in the accumulators increases in a linear and deterministic manner. The simplicity of the model allows…

  17. 76 FR 81004 - Imposition of Nonproliferation Measures Against Foreign Persons, Including a Ban on U.S...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-27

    ... control lists (Missile Technology Control Regime, Australia Group, Chemical Weapons Convention, Nuclear... the development of weapons of mass destruction (WMD) or cruise or ballistic missile systems. The... contribution to WMD or cruise or ballistic missile systems, (b) other items with the potential of making such a...

  18. 78 FR 9768 - Bureau of International Security and Nonproliferation Imposition of Nonproliferation Measures...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... technology controlled under multilateral control lists (Missile Technology Control Regime, Australia Group... or ballistic missile sytems. The latter category includes (a) items of the same kind as those on... potential of making a material contribution to WMD or cruise or ballistic missile systems, (b) items on U.S...

  19. Interaction of Rate of Force Development and Duration of Rate in Isometric Force.

    ERIC Educational Resources Information Center

    Siegel, Donald

    A study attempted to determine whether force and duration parameters are programmed in an interactive or independent fashion prior to executing ballistic type isometric contractions of graded intensities. Four adult females each performed 360 trials of producing ballistic type forces representing 25, 40, 55, and 75 percent of their maximal…

  20. Development of a Ballistic Specification for Magnesium Alloy AZ31B

    DTIC Science & Technology

    2008-12-01

    REPORT TYPE Final 3. DATES COVERED (From - To) June 2007– July 2008 4. TITLE AND SUBTITLE Development of a Ballistic Specification for Magnesium Alloy...SEAMAN D SHOCKEY 333 RAVENSWOOD AVE MENLO PARK CA 94025 6 RMI TITANIUM CO J BENNETT E CHRIST F JANOWSKI W PALLANTE S ROBERTSON

  1. [Abdominal gunshot wounds. Ballistic data and practical management].

    PubMed

    Vicq, P; Jourdan, P; Chapuis, O; Baranger, B

    1996-01-01

    The mortality from abdominal gunshot wounds remains high, either in civilian or military cases. The severity factors of these wounds include bullet calibre and energy transfer of the missile. This paper studies some of the ballistics features of abdominal gunshot wounds. Practical guidelines are inferred concerning diagnosis and treatment of these wounds.

  2. Fortran Programs for Weapon Systems Analysis

    DTIC Science & Technology

    1990-06-01

    interested in ballistics and related work. The programs include skeletal combat models , a set of discrete-event timing routines, mathematical and...32 4.3 LinEqs: Solve Linear Equations Like a Textbook ........................................................................... 34...military applications as it is of computer science. This crisis occurs in all fields, including the modeling of logistics, mobility, ballistics, and combat

  3. The relationship between mechanical properties and ballistic penetration depth in a viscoelastic gel.

    PubMed

    Mrozek, Randy A; Leighliter, Brad; Gold, Christopher S; Beringer, Ian R; Yu, Jian H; VanLandingham, Mark R; Moy, Paul; Foster, Mark H; Lenhart, Joseph L

    2015-04-01

    The fundamental material response of a viscoelastic material when impacted by a ballistic projectile has important implication for the defense, law enforcement, and medical communities particularly for the evaluation of protective systems. In this paper, we systematically vary the modulus and toughness of a synthetic polymer gel to determine their respective influence on the velocity-dependent penetration of a spherical projectile. The polymer gels were characterized using tensile, compression, and rheological testing taking special care to address the unique challenges associated with obtaining high fidelity mechanical data on highly conformal materials. The depth of penetration data was accurately described using the elastic Froude number for viscoelastic gels ranging in Young's modulus from ~60 to 630 kPa. The minimum velocity of penetration was determined to scale with the gel toughness divided by the gel modulus, a qualitative estimate for the zone of deformation size scale upon impact. We anticipate that this work will provide insight into the critical material factors that control ballistic penetration behavior in soft materials and aid in the design and development of new ballistic testing media. Published by Elsevier Ltd.

  4. Wound ballistic evaluation of the Taser® XREP ammunition.

    PubMed

    Kunz, Sebastian N; Adamec, Jiri; Zinka, Bettina; Münzel, Daniela; Noël, Peter B; Eichner, Simon; Manthei, Axel; Grove, Nico; Graw, M; Peschel, Oliver

    2013-01-01

    The Taser® eXtended Range Electronic Projectile (XREP®) is a wireless conducted electrical weapon (CEW) designed to incapacitate a person from a larger distance. The aim of this study was to analyze the ballistic injury potential of the XREP. Twenty rounds were fired from the Taser®X12 TM shotgun into ballistic soap covered with artificial skin and clothing at different shooting distances (1-25 m). One shot was fired at pig skin at a shooting distance of 10 m. The average projectile velocity was 67.0 m/s. The kinetic energy levels on impact varied from 28-52 J. Depending on the intermediate target, the projectiles penetrated up to 4.2 cm into the ballistic soap. On impact the nose assembly did not separate from the chassis, and no electrical activation was registered. Upon impact, a skin penetration of the XREP cannot be excluded. However, it is very unlikely at shooting distances of 10 m or more. Clothing and a high elasticity limit of the target body area can significantly reduce the penetration risk on impact.

  5. Targeting Low-Energy Ballistic Lunar Transfers

    NASA Technical Reports Server (NTRS)

    Parker, Jeffrey S.

    2010-01-01

    Numerous low-energy ballistic transfers exist between the Earth and Moon that require less fuel than conventional transfers, but require three or more months of transfer time. An entirely ballistic lunar transfer departs the Earth from a particular declination at some time in order to arrive at the Moon at a given time along a desirable approach. Maneuvers may be added to the trajectory in order to adjust the Earth departure to meet mission requirements. In this paper, we characterize the (Delta)V cost required to adjust a low-energy ballistic lunar transfer such that a spacecraft may depart the Earth at a desirable declination, e.g., 28.5(white bullet), on a designated date. This study identifies the optimal locations to place one or two maneuvers along a transfer to minimize the (Delta)V cost of the transfer. One practical application of this study is to characterize the launch period for a mission that aims to launch from a particular launch site, such as Cape Canaveral, Florida, and arrive at a particular orbit at the Moon on a given date using a three-month low-energy transfer.

  6. Coherent Charge Transport in Ballistic InSb Nanowire Josephson Junctions

    PubMed Central

    Li, S.; Kang, N.; Fan, D. X.; Wang, L. B.; Huang, Y. Q.; Caroff, P.; Xu, H. Q.

    2016-01-01

    Hybrid InSb nanowire-superconductor devices are promising for investigating Majorana modes and topological quantum computation in solid-state devices. An experimental realisation of ballistic, phase-coherent superconductor-nanowire hybrid devices is a necessary step towards engineering topological superconducting electronics. Here, we report on a low-temperature transport study of Josephson junction devices fabricated from InSb nanowires grown by molecular-beam epitaxy and provide a clear evidence for phase-coherent, ballistic charge transport through the nanowires in the junctions. We demonstrate that our devices show gate-tunable proximity-induced supercurrent and clear signatures of multiple Andreev reflections in the differential conductance, indicating phase-coherent transport within the junctions. We also observe periodic modulations of the critical current that can be associated with the Fabry-Pérot interference in the nanowires in the ballistic transport regime. Our work shows that the InSb nanowires grown by molecular-beam epitaxy are of excellent material quality and hybrid superconducting devices made from these nanowires are highly desirable for investigation of the novel physics in topological states of matter and for applications in topological quantum electronics. PMID:27102689

  7. Local and distant trauma after hypervelocity ballistic impact to the pig hind limb.

    PubMed

    Chen, Jin; Zhang, Bo; Chen, Wei; Kang, Jian-Yi; Chen, Kui-Jun; Wang, Ai-Min; Wang, Jian-Min

    2016-01-01

    The development of high-energy weapons could increase the velocity of projectiles to well over 1000 m/s. The nature of the injuries caused by the ballistic impact of projectiles at velocities much faster than 1000 m/s is unclear. This study characterizes the mechanical and biochemical alterations caused by high-speed ballistic impact generated by spherical steel ball to the hind limbs of the pig. That the local and distal injuries caused by hypervelocity ballistic impact to the living body are also identified. It is showed that the severity of the injury was positively correlated with the velocity of the projectile. And 4000 m/s seems to be the critical velocity for the 5.6 mm spherical steel ball, which would cause severe damage to either local or distal organs, as below that speed the projectile penetrated the body while above that speed it caused severe damage to the body. In addition, vaporization prevented the projectile from penetrating the body and the consequent pressure wave seems to be the causal factor for the distant damage.

  8. Investigation of thermal effects on FinFETs in the quasi-ballistic regime

    NASA Astrophysics Data System (ADS)

    Yin, Longxiang; Shen, Lei; Di, Shaoyan; Du, Gang; Liu, Xiaoyan

    2018-04-01

    In this work, the thermal effects of FinFETs in the quasi-ballistic regime are investigated using the Monte Carlo method. Bulk Si nFinFETs with the same fin structure and two different gate lengths L g = 20 and 80 nm are investigated and compared to evaluate the thermal effects on the performance of FinFETs in the quasi-ballistic regime. The on current of the 20 nm FinFET with V gs = 0.7 V does not decrease with increasing lattice temperature (T L) at a high V ds. The electrostatic properties in the 20 nm FinFET are more affected by T L than those in the 80 nm FinFET. However, the electron transport in the 20 nm FinFET is less affected by T L than that in the 80 nm FinFET. The electrostatic properties being more sensitive and the electron transport being less sensitive to thermal effects in the quasi-ballistic regime than in the diffusive regime should be considered for effective device modeling and design.

  9. Ballistic food transport in toucans.

    PubMed

    Baussart, Sabine; Korsoun, Leonid; Libourel, Paul-Antoine; Bels, Vincent

    2009-08-01

    The basic mechanism of food transport in tetrapods is lingual-based. Neognathous birds use this mechanism for exploiting a large diversity of food resources, whereas paleognathous birds use cranioinertial mechanism with or without tongue involvement. Food transport in two neognathous species of toucans (Ramphastos toco and R. vitellinus) is defined as ballistic transport mechanism. Only one transport cycle is used for moving the food from the tip of the beak to the pharynx. The food is projected between jaws with similar initial velocity in both species. At the time of release, the angle between trajectory of food position and horizontal is higher in R. vitellinus with a shorter beak than in R. toco. The tongue never makes contact with the food nor is it used to expand the buccal cavity. Tongue movement is associated with throat expansion, permitting the food to reach the entrance of the esophagus at the end of the ballistic trajectory. Selection of large food items in the diet may explain the evolutionary trend of using ballistic transport in the feeding behavior of toucans, which plays a key role in ecology of tropical forest. 2009 Wiley-Liss, Inc.

  10. The use of gelatine in wound ballistics research.

    PubMed

    Carr, D J; Stevenson, T; Mahoney, P F

    2018-04-25

    Blocks of gelatine are used in both lethality and survivability studies for broadly the same reason, i.e. comparison of ammunition effects using a material that it is assumed represents (some part of) the human body. The gelatine is used to visualise the temporary and permanent wound profiles; elements of which are recognised as providing a reasonable approximation to wounding in humans. One set of researchers aim to improve the lethality of the projectile, and the other to understand the effects of the projectile on the body to improve survivability. Research areas that use gelatine blocks are diverse and include ammunition designers, the medical and forensics communities and designers of ballistic protective equipment (including body armour). This paper aims to provide an overarching review of the use of gelatine for wound ballistics studies; it is not intended to provide an extensive review of wound ballistics as that already exists, e.g. Legal Med 23:21-29, 2016. Key messages are that test variables, projectile type (bullet, fragmentation), impact site on the body and intermediate layers (e.g. clothing, personal protective equipment (PPE)) can affect the resulting wound profiles.

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harvey, J.R.; Rubin, U.

    Missiles themselves are not weapons of mass destruction; they do not give states the ability to wreak unimaginable destruction, or to radically shift the balance of power, as nuclear weapons do. Hence, the primary focus of nonproliferation efforts should remain on weapons of mass destruction, particularly nuclear weapons, rather than on one of the many possible means of delivering them. Moreover, as discussed in more detail below, advanced strike aircraft can also be effective in delivering nuclear weapons, and are generally more effective than ballistic missiles for delivering conventional or chemical ordnance. Ultimately, if the industrialized nations seriously desire tomore » control the spread of delivery means for weapons of mass destruction, they need to consider bringing controls over ballistic missiles and advanced strike aircraft more into balance. At the same time, while efforts to control ballistic missile proliferation - centered on the Missile Technology Control Regime (MTCR) - have had some successes and could be strengthened, US policy will be most effective if it recognizes two key realities: the spread of ballistic missiles cannot be as comprehensively controlled as the spread of nuclear weapons, nor need it be as comprehensively controlled.« less

  12. Historical overview of wound ballistics research.

    PubMed

    Maiden, Nick

    2009-01-01

    Ballistics involves the study of the scientific properties of projectiles, their behavior and their terminal effects on biological tissues and other materials. Wound ballistics deals with the analysis of injuries caused by projectiles and the behavior of projectiles within human or other biological tissues. The nineteenth century witnessed the development of both of these areas with Kocher's hydrodynamic theory and the understanding of the significance of bullet deformation in causing tissue injury. The degree of traumatic disruption of tissues and organs was also related to direct energy transfer from projectiles. While subsequent research has concentrated on elucidating further mechanisms of injury, the exact cause of remote tissue damage from high energy projectiles is still the subject of ongoing research. Much of the contemporary literature regarding wound ballistics concentrates on the forensic aspects and their application for legal purposes, in particular the investigation of shooting scenes. There have been many advances in this area, particularly in relation to the identification of various types of gunshot wounds and how their appearance can be used to establish if a shooting was accidental, deliberate (homicidal) or self inflicted (suicidal).

  13. Charging conditions research to increase the initial projected velocity at different initial charge temperatures

    NASA Astrophysics Data System (ADS)

    Ishchenko, Aleksandr; Burkin, Viktor; Kasimov, Vladimir; Samorokova, Nina; Zykova, Angelica; Diachkovskii, Alexei

    2017-11-01

    The problems of the defense industry occupy the most important place in the constantly developing modern world. The daily development of defense technology does not stop, nor do studies on internal ballistics. The scientists of the whole world are faced with the task of managing the main characteristics of a ballistic experiment. The main characteristics of the ballistic experiment are the maximum pressure in the combustion chamber Pmax and the projected velocity at the time of barrel leaving UM. During the work the combustion law of the new high-energy fuel was determined in a ballistic experiment for different initial temperatures. This combustion law was used for a parametric study of depending Pmax and UM from a powder charge mass and a traveling charge was carried out. The optimal conditions for loading were obtained for improving the initial velocity at pressures up to 600 MPa for different initial temperatures. In this paper, one of the most promising schemes of throwing is considered, as well as a method for increasing the muzzle velocity of a projected element to 3317 m/s.

  14. Thermo-Electron Ballistic Coolers or Heaters

    NASA Technical Reports Server (NTRS)

    Choi, Sang H.

    2003-01-01

    Electronic heat-transfer devices of a proposed type would exploit some of the quantum-wire-like, pseudo-superconducting properties of single-wall carbon nanotubes or, optionally, room-temperature-superconducting polymers (RTSPs). The devices are denoted thermo-electron ballistic (TEB) coolers or heaters because one of the properties that they exploit is the totally or nearly ballistic (dissipation or scattering free) transport of electrons. This property is observed in RTSPs and carbon nanotubes that are free of material and geometric defects, except under conditions in which oscillatory electron motions become coupled with vibrations of the nanotubes. Another relevant property is the high number density of electrons passing through carbon nanotubes -- sufficient to sustain electron current densities as large as 100 MA/square cm. The combination of ballistic motion and large current density should make it possible for TEB devices to operate at low applied potentials while pumping heat at rates several orders of magnitude greater than those of thermoelectric devices. It may also enable them to operate with efficiency close to the Carnot limit. In addition, the proposed TEB devices are expected to operate over a wider temperature range

  15. Optimal ballistically captured Earth-Moon transfers

    NASA Astrophysics Data System (ADS)

    Ricord Griesemer, Paul; Ocampo, Cesar; Cooley, D. S.

    2012-07-01

    The optimality of a low-energy Earth-Moon transfer terminating in ballistic capture is examined for the first time using primer vector theory. An optimal control problem is formed with the following free variables: the location, time, and magnitude of the transfer insertion burn, and the transfer time. A constraint is placed on the initial state of the spacecraft to bind it to a given initial orbit around a first body, and on the final state of the spacecraft to limit its Keplerian energy with respect to a second body. Optimal transfers in the system are shown to meet certain conditions placed on the primer vector and its time derivative. A two point boundary value problem containing these necessary conditions is created for use in targeting optimal transfers. The two point boundary value problem is then applied to the ballistic lunar capture problem, and an optimal trajectory is shown. Additionally, the problem is then modified to fix the time of transfer, allowing for optimal multi-impulse transfers. The tradeoff between transfer time and fuel cost is shown for Earth-Moon ballistic lunar capture transfers.

  16. Drag of ballistic electrons by an ion beam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gurevich, V. L.; Muradov, M. I., E-mail: mag.muradov@mail.ioffe.ru

    2015-12-15

    Drag of electrons of a one-dimensional ballistic nanowire by a nearby one-dimensional beam of ions is considered. We assume that the ion beam is represented by an ensemble of heavy ions of the same velocity V. The ratio of the drag current to the primary current carried by the ion beam is calculated. The drag current turns out to be a nonmonotonic function of velocity V. It has a sharp maximum for V near v{sub nF}/2, where n is the number of the uppermost electron miniband (channel) taking part in conduction and v{sub nF} is the corresponding Fermi velocity. Thismore » means that the phenomenon of ion beam drag can be used for investigation of the electron spectra of ballistic nanostructures. We note that whereas observation of the Coulomb drag between two parallel quantum wires may in general be complicated by phenomena such as tunneling and phonon drag, the Coulomb drag of electrons of a one-dimensional ballistic nanowire by an ion beam is free of such spurious effects.« less

  17. Diffusive and inelastic scattering in ballistic-electron-emission spectroscopy and ballistic-electron-emission microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, E.Y.; Turner, B.R.; Schowalter, L.J.

    1993-07-01

    Ballistic-electron-emission microscopy (BEEM) of Au/Si(001) n type was done to study whether elastic scattering in the Au overlayer is dominant. It was found that there is no dependence of the BEEM current on the relative gradient of the Au surface with respect to the Si interface, and this demonstrates that significant elastic scattering must occur in the Au overlayer. Ballistic-electron-emission spectroscopy (BEES) was also done, and, rather than using the conventional direct-current BEES, alternating-current (ac) BEES was done on Au/Si and also on Au/PtSi/Si(001) n type. The technique of ac BEES was found to give linear threshold for the Schottkymore » barrier, and it also clearly showed the onset of electron-hole pair creation and other inelastic scattering events. The study of device quality PtSi in Au/PtSi/Si(001) yielded an attenuation length of 4 nm for electrons of energy 1 eV above the PtSi Fermi energy. 20 refs., 5 figs.« less

  18. Computational Investigation of Effects of Grain Size on Ballistic Performance of Copper

    NASA Astrophysics Data System (ADS)

    He, Ge; Dou, Yangqing; Guo, Xiang; Liu, Yucheng

    2018-01-01

    Numerical simulations were conducted to compare ballistic performance and penetration mechanism of copper (Cu) with four representative grain sizes. Ballistic limit velocities for coarse-grained (CG) copper (grain size ≈ 90 µm), regular copper (grain size ≈ 30 µm), fine-grained (FG) copper (grain size ≈ 890 nm), and ultrafine-grained (UG) copper (grain size ≈ 200 nm) were determined for the first time through the simulations. It was found that the copper with reduced grain size would offer higher strength and better ductility, and therefore renders improved ballistic performance than the CG and regular copper. High speed impact and penetration behavior of the FG and UG copper was also compared with the CG coppers strengthened by nanotwinned (NT) regions. The comparison results showed the impact and penetration resistance of UG copper is comparable to the CG copper strengthened by NT regions with the minimum twin spacing. Therefore, besides the NT-strengthened copper, the single phase copper with nanoscale grain size could also be a strong candidate material for better ballistic protection. A computational modeling and simulation framework was proposed for this study, in which Johnson-Cook (JC) constitutive model is used to predict the plastic deformation of Cu; the JC damage model is to capture the penetration and fragmentation behavior of Cu; Bao-Wierzbicki (B-W) failure criterion defines the material's failure mechanisms; and temperature increase during this adiabatic penetration process is given by the Taylor-Quinney method.

  19. Ballistic parameters and trauma potential of direct-acting, powder-actuated fastening tools (nail guns).

    PubMed

    Frank, Matthias; Franke, Ernst; Schönekess, Holger C; Jorczyk, Jörn; Bockholdt, Britta; Ekkernkamp, Axel

    2012-03-01

    Since their introduction in the 1950s in the construction and building trade, powder-actuated fastening tools (nail guns) are of forensic and traumatological importance. There are countless reports on both accidental and intentional injuries and fatalities caused by these tools in medical literature. While the ballistic parameters of so-called low-velocity fastening tools, where the expanding gases act on a captive piston that drives the fastener into the material, are well known, ballistic parameters of "high-velocity" tools, which operate like a firearm and release the energy of the propellant directly on the fastener, are unknown. Therefore, it was the aim of this work to investigate external ballistic parameters of cal. 9 and 6-mm fastening bolts discharged from four different direct-acting nail guns (Type Ideal, Record Piccolo S, Rapid Hammer R300, Titan Type 1). Average muzzle velocity ranged from 400 to 580 m/s, while average kinetic energy of the projectiles ranged from 385 to 547 J. Mean energy density of the projectiles ranged from 9 to 18 J/mm(2). To conclude, this work demonstrates that the muzzle velocity of direct-acting high-velocity tools is approximately five times higher than the muzzle velocity of piston-type tools. Hence, the much-cited comparison to the ballistic parameters of a cal. 22 handgun might be understated and a comparison to the widespread and well-known cal. 9 mm Luger might be more appropriate.

  20. Evaluation of bone surrogates for indirect and direct ballistic fractures.

    PubMed

    Bir, Cynthia; Andrecovich, Chris; DeMaio, Marlene; Dougherty, Paul J

    2016-04-01

    The mechanism of injury for fractures to long bones has been studied for both direct ballistic loading as well as indirect. However, the majority of these studies have been conducted on both post-mortem human subjects (PMHS) and animal surrogates which have constraints in terms of storage, preparation and testing. The identification of a validated bone surrogate for use in forensic, medical and engineering testing would provide the ability to investigate ballistic loading without these constraints. Two specific bone surrogates, Sawbones and Synbone, were evaluated in comparison to PMHS for both direct and indirect ballistic loading. For the direct loading, the mean velocity to produce fracture was 121 ± 19 m/s for the PMHS, which was statistically different from the Sawbones (140 ± 7 m/s) and Synbone (146 ± 3 m/s). The average distance to fracture in the indirect loading was .70 cm for the PMHS. The Synbone had a statistically similar average distance to fracture (.61 cm, p=0.54) however the Sawbones average distance to fracture was statistically different (.41 cm, p<0.05). Fractures patterns were found to be comparable to the PMHS for tests conducted with Synbones, however the input parameters were slightly varied to produce similar results. The fractures patterns with the Sawbones were not found to be as comparable to the PMHS. An ideal bone surrogate for ballistic testing was not identified and future work is warranted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Task-dependent activation of distinct fast and slow(er) motor pathways during motor imagery.

    PubMed

    Keller, Martin; Taube, Wolfgang; Lauber, Benedikt

    2018-02-22

    Motor imagery and actual movements share overlapping activation of brain areas but little is known about task-specific activation of distinct motor pathways during mental simulation of movements. For real contractions, it was demonstrated that the slow(er) motor pathways are activated differently in ballistic compared to tonic contractions but it is unknown if this also holds true for imagined contractions. The aim of the present study was to assess the activity of fast and slow(er) motor pathways during mentally simulated movements of ballistic and tonic contractions. H-reflexes were conditioned with transcranial magnetic stimulation at different interstimulus intervals to assess the excitability of fast and slow(er) motor pathways during a) the execution of tonic and ballistic contractions, b) motor imagery of these contraction types, and c) at rest. In contrast to the fast motor pathways, the slow(er) pathways displayed a task-specific activation: for imagined ballistic as well as real ballistic contractions, the activation was reduced compared to rest whereas enhanced activation was found for imagined tonic and real tonic contractions. This study provides evidence that the excitability of fast and slow(er) motor pathways during motor imagery resembles the activation pattern observed during real contractions. The findings indicate that motor imagery results in task- and pathway-specific subliminal activation of distinct subsets of neurons in the primary motor cortex. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  2. Stability analyses of the mass abrasive projectile high-speed penetrating into a concrete target Part III: Terminal ballistic trajectory analyses

    NASA Astrophysics Data System (ADS)

    Wu, H.; Chen, X. W.; Fang, Q.; Kong, X. Z.; He, L. L.

    2015-08-01

    During the high-speed penetration of projectiles into concrete targets (the impact velocity ranges from 1.0 to 1.5 km/s), important factors such as the incident oblique and attacking angles, as well as the asymmetric abrasions of the projectile nose induced by the target-projectile interactions, may lead to obvious deviation of the terminal ballistic trajectory and reduction of the penetration efficiency. Based on the engineering model for the mass loss and nose-blunting of ogive-nosed projectiles established, by using the Differential Area Force Law (DAFL) method and semi-empirical resistance function, a finite differential approach was programmed (PENTRA2D) for predicting the terminal ballistic trajectory of mass abrasive high-speed projectiles penetrating into concrete targets. It accounts for the free-surface effects on the drag force acting on the projectile, which are attributed to the oblique and attacking angles, as well as the asymmetric nose abrasion of the projectile. Its validation on the prediction of curvilinear trajectories of non-normal high-speed penetrators into concrete targets is verified by comparison with available test data. Relevant parametric influential analyses show that the most influential factor for the stability of terminal ballistic trajectories is the attacking angle, followed by the oblique angle, the discrepancy of asymmetric nose abrasion, and the location of mass center of projectile. The terminal ballistic trajectory deviations are aggravated as the above four parameters increase.

  3. Effects of plyometric and isometric training on muscle and tendon stiffness in vivo.

    PubMed

    Kubo, Keitaro; Ishigaki, Tomonobu; Ikebukuro, Toshihiro

    2017-08-01

    The purpose of this study was to compare the effects of plyometric and isometric training on tendon properties during ramp and ballistic contractions and muscle stiffness under passive and active conditions. Eleven subjects completed 12 weeks (3 days/week) of a unilateral training program for the plantar flexors. They performed plyometric training on one side (PLY) and isometric training on the other side (ISO). Active muscle stiffness in the medial gastrocnemius muscle was calculated according to changes in estimated muscle force and fascicle length during fast stretching after submaximal isometric contractions. Passive muscle stiffness was also calculated from estimated passive muscle force and fascicle length during slow passive stretching. Stiffness and hysteresis of tendon structures were measured using ultrasonography during ramp and ballistic contractions. Passive muscle stiffness and tendon hysteresis did not change for PLY or ISO Active muscle stiffness significantly increased for PLY, but not for ISO Tendon stiffness during ramp and ballistic contractions increased significantly for ISO, but not for PLY In addition, tendon elongation values at force production levels beyond 100 N during ballistic contractions increased for PLY These results suggest that plyometric training (but not isometric training) enhances the extensibility of tendon structures during ballistic contractions and active muscle stiffness during fast stretching, and these changes may be related to improved performances during stretch-shortening cycle exercises. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  4. Image-guided percutaneous removal of ballistic foreign bodies secondary to air gun injuries.

    PubMed

    Rothermund, Jacob L; Rabe, Andrew J; Zumberge, Nicholas A; Murakami, James W; Warren, Patrick S; Hogan, Mark J

    2018-01-01

    Ballistic injuries with retained foreign bodies from air guns is a relatively common problem, particularly in children and adolescents. If not removed in a timely fashion, the foreign bodies can result in complications, including pain and infection. Diagnostic methods to identify the presence of the foreign body run the entire gamut of radiology, particularly radiography, ultrasound (US) and computed tomography (CT). Removal of the foreign bodies can be performed by primary care, emergency, surgical, and radiologic clinicians, with or without imaging guidance. To evaluate the modalities of radiologic detection and the experience of image-guided ballistic foreign body removal related to air gun injuries within the interventional radiology department of a large pediatric hospital. A database of more than 1,000 foreign bodies that were removed with imaging guidance by the interventional radiologists at our institution was searched for ballistic foreign bodies from air guns. The location, dimensions, diagnostic modality, duration, complications and imaging modality used for removal were recorded. In addition, the use of sedation and anesthesia required for the procedures was also recorded. Sixty-one patients with ballistic foreign bodies were identified. All foreign bodies were metallic BBs or pellets. The age of the patients ranged from 5 to 20 years. The initial diagnostic modality to detect the foreign bodies was primarily radiography. The primary modality to assist in removal was US, closely followed by fluoroscopy. For the procedure, 32.7% of the patients required some level of sedation. Only two patients had an active infection at the time of the removal. The foreign bodies were primarily in the soft tissues; however, successful removal was also performed from intraosseous, intraglandular and intratendinous locations. All cases resulted in successful removal without complications. Image-guided removal of ballistic foreign bodies secondary to air guns is a very effective procedure that can obviate the need for open surgical procedures in children.

  5. Voluntary Control of Residual Antagonistic Muscles in Transtibial Amputees: Feedforward Ballistic Contractions and Implications for Direct Neural Control of Powered Lower Limb Prostheses.

    PubMed

    Huang, Stephanie; Huang, He

    2018-04-01

    Discrete, rapid (i.e., ballistic like) muscle activation patterns have been observed in ankle muscles (i.e., plantar flexors and dorsiflexors) of able-bodied individuals during voluntary posture control. This observation motivated us to investigate whether transtibial amputees are capable of generating such a ballistic-like activation pattern accurately using their residual ankle muscles in order to assess whether the volitional postural control of a powered ankle prosthesis using proportional myoelectric control via residual muscles could be feasible. In this paper, we asked ten transtibial amputees to generate ballistic-like activation patterns using their residual lateral gastrocnemius and residual tibialis anterior to control a computer cursor via proportional myoelectric control to hit targets positioned at 20% and 40% of maximum voluntary contraction of the corresponding residual muscle. During practice conditions, we asked amputees to hit a single target repeatedly. During testing conditions, we asked amputees to hit a random sequence of targets. We compared movement time to target and end-point accuracy. We also examined motor recruitment synchronization via time-frequency representations of residual muscle activation. The result showed that median end-point error ranged from -0.6% to 1% maximum voluntary contraction across subjects during practice, which was significantly lower compared to testing ( ). Average movement time for all amputees was 242 ms during practice and 272 ms during testing. Motor recruitment synchronization varied across subjects, and amputees with the highest synchronization achieved the fastest movement times. End-point accuracy was independent of movement time. Results suggest that it is feasible for transtibial amputees to generate ballistic control signals using their residual muscles. Future work on volitional control of powered power ankle prostheses might consider anticipatory postural control based on ballistic-like residual muscle activation patterns and direct continuous proportional myoelectric control.

  6. Lead-Free Double-Base Propellant for the 2.75 Inch Rocket Motor

    NASA Technical Reports Server (NTRS)

    Magill, B. T.; Nauflett, G. W.; Furrow, K. W.

    2000-01-01

    The current MK 66 2.75 inch Rocket Motor double-base propellant contains the lead-based ballistic modifier LC-12-15 to achieve the desired plateau and mesa burning rate characteristics. The use of lead compounds poses a concern for the environment and for personal safety due to the metal's toxic nature when introduced into the atmosphere by propellant manufacture, rocket motor firing, and disposal. Copper beta-resorcylate (copper 2,4-di-hydroxy-benzoate) was successfully used in propellant as a simple modifier in the mid 1970's. This and other compounds have also been mixed with lead salts to obtain more beneficial ballistic results. Synthesized complexes of lead and copper compounds soon replaced the mixtures. The complexes incorporate the lead, copper lack of organic liquids, which allows for easier propellant processing. About ten years ago, the Indian Head Division, Naval Surface Warfare Center (NSWC), initiated an effort to develop a lead-free propellant for use in missile systems. Several lead-free propellant candidate formulations were developed. About five years ago, NSWC, in conjunction with Alliant Techsystems, Radford Army Ammunition Plant, continued ballistic modifier investigations. A four component ballistic modifier system without lead for double-base propellants that provide adequate plateau and mesa burn rate characteristics was developed and patented. The ballistic modifier's system contains bismuth subsalicylate, 1.5 percent; copper salicylate, 1.0 percent, copper stannate, 0.77 percent; and carbon black, 0.1 percent. Action time and impulse data obtained through multiple static firings indicate that the new lead-free double-base propellant, while not a match for NOSIH-AA-2, will be a very suitable replacement in the 2.75 inch Rocket Motor. Accelerated aging of the double-base propellant containing the lead-free ballistic modifier showed that it had a much higher rate of stabilizer depletion than the AA-2. A comprehensive study showed that an increased rate of stabilizer depletion occurred in propellants containing monobasic copper salicylate. The study also showed that propellants containing a mixture of bismuth subsalicylate and copper salicylate, had only about one-half the stabilizer depletion rate than those with copper salicylate alone. The copper salicylate catalyzes the decomposition of nitroglycerin, which triggers a chain of events leading to the increased rate of stabilizer depletion. A program has been initiated to coat the ballistic modifier, thus isolating it from the nitroglycerin.

  7. Optimal control of the ballistic motion of Airy beams.

    PubMed

    Hu, Yi; Zhang, Peng; Lou, Cibo; Huang, Simon; Xu, Jingjun; Chen, Zhigang

    2010-07-01

    We demonstrate the projectile motion of two-dimensional truncated Airy beams in a general ballistic trajectory with controllable range and height. We show that the peak beam intensity can be delivered to any desired location along the trajectory as well as repositioned to a given target after displacement due to propagation through disordered or turbulent media.

  8. On the Trajectories of Projectiles Depicted in Early Ballistic Woodcuts

    ERIC Educational Resources Information Center

    Stewart, Sean M.

    2012-01-01

    Motivated by quaint woodcut depictions often found in many late 16th and 17th century ballistic manuals of cannonballs fired in air, a comparison of their shapes with those calculated for the classic case of a projectile moving in a linear resisting medium is made. In considering the asymmetrical nature of such trajectories, the initial launch…

  9. Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues

    DTIC Science & Technology

    2014-05-05

    13 The FALCON Study...bombers, cruise missiles, ballistic missiles, and boost-glide technologies that would mate a rocket booster with a hypersonic glide vehicle. Congress has...Strategic Command, Hearing, April 4, 2005. 23 Grossman, Elaine M., “U.S. General: Precise Long-Range Missiles may Enable Big Nuclear Cuts,” Inside the

  10. Multifunctional Nanocomposites for Improved Sustainability and Protection of Facilities

    DTIC Science & Technology

    2015-05-01

    ballistic panels. In addition, the team’s work tested various options for adding self - healing , CNT reinforcement, EMI shielding, and self ...and functional- ization methods; introducing a self - healing agent directly to the matrix or contained in embedded hollow glass fibers; using layers...using CNT sheet reinforcement ...................... 23 5 Ballistic Testing of Self - Healing GFRP Panel

  11. Complex Burn Region Module (CBRM) update

    NASA Technical Reports Server (NTRS)

    Adams, Carl L.; Jenkins, Billy

    1991-01-01

    Presented here is a Complex Burn Region Module (CBRM) update for the Solid Rocket Internal Ballistics Module (SRIBM) Program for the Advanced Solid Rocket Motor (ASRM) design/performance assessments. The goal was to develop an improved version of the solid rocket internal ballistics module program that contains a diversified complex region model for motor grain design, performance prediction, and evaluation.

  12. Soviet Concepts of Ballistic Missile Defense

    DTIC Science & Technology

    1988-06-01

    manned space operations, ABM Treaty, SDI 19 Abstract (continue on reverse if necessary and identify by block number The purpose of this thesis is to...THE EARLY YEARS OF SOVIET BMD ................................................ 6 B. SOVIET BMD AND THE ABM TREATY OF 1972...10 C. SOVIET BMD SINCE THE ABM TREATY .......................................... 14 III. BALLISTIC MISSILE DEFENSE IN SOVIET MILITARY THOUGHT

  13. Early Rockets

    NASA Image and Video Library

    1958-01-31

    Jupiter-C Missile No. 27 assembly at the Army Ballistic Missile Agency (ABMA), Redstone Arsenal, in Huntsville, Aalabama. The Jupiter-C was a modification of the Redstone Missile, and originally developed as a nose cone re-entry test vehicle for the Jupiter Intermediate Range Ballistic Missile (IRBM). Jupiter-C successfully launched the first American Satellite, Explorer 1, in orbit on January 31, 1958.

  14. Quantized magnetoresistance in atomic-size contacts.

    PubMed

    Sokolov, Andrei; Zhang, Chunjuan; Tsymbal, Evgeny Y; Redepenning, Jody; Doudin, Bernard

    2007-03-01

    When the dimensions of a metallic conductor are reduced so that they become comparable to the de Broglie wavelengths of the conduction electrons, the absence of scattering results in ballistic electron transport and the conductance becomes quantized. In ferromagnetic metals, the spin angular momentum of the electrons results in spin-dependent conductance quantization and various unusual magnetoresistive phenomena. Theorists have predicted a related phenomenon known as ballistic anisotropic magnetoresistance (BAMR). Here we report the first experimental evidence for BAMR by observing a stepwise variation in the ballistic conductance of cobalt nanocontacts as the direction of an applied magnetic field is varied. Our results show that BAMR can be positive and negative, and exhibits symmetric and asymmetric angular dependences, consistent with theoretical predictions.

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kennedy, W.S.; Kovacic, S.M.; Rea, E.C.

    The development of ballistic missiles and particularly intercontinental ballistic missiles (ICBMs) by the U.S. space technology manufacturer is examined. Collaboration by the company with the U.S. Air Force is described which began in the 1950s and combined systems engineering and technical assistance. Missile products reviewed in this paper include Atlas, Thor, Titans I and II, Minuteman I, II, III, the Peacekeeper, and the small ICBM. The company developed facilities and programs to support the R and D activities for the missile products, and descriptions are given of the Space Technologies Laboratory and the Ballistic Missiles Division. Contributions to ICBM technologiesmore » by the concern include carbon-carbon nozzle materials, propellant formulation data, movable nozzles, casting techniques for large volumes of propellants, and studies of fracture mechanics. 41 refs.« less

  16. A Klein-tunneling transistor with ballistic graphene

    NASA Astrophysics Data System (ADS)

    Wilmart, Quentin; Berrada, Salim; Torrin, David; Nguyen, V. Hung; Fève, Gwendal; Berroir, Jean-Marc; Dollfus, Philippe; Plaçais, Bernard

    2014-06-01

    Today, the availability of high mobility graphene up to room temperature makes ballistic transport in nanodevices achievable. In particular, p-n-p transistors in the ballistic regime give access to Klein tunneling physics and allow the realization of devices exploiting the optics-like behavior of Dirac Fermions (DFs) as in the Veselago lens or the Fabry-Pérot cavity. Here we propose a Klein tunneling transistor based on the geometrical optics of DFs. We consider the case of a prismatic active region delimited by a triangular gate, where total internal reflection may occur, which leads to the tunable suppression of transistor transmission. We calculate the transmission and the current by means of scattering theory and the finite bias properties using non-equilibrium Green's function (NEGF) simulation.

  17. Opportunities for ballistic missions to Halley's comet

    NASA Technical Reports Server (NTRS)

    Farquhar, R. W.; Wooden, W. H., II

    1977-01-01

    Alternative strategies for ballistic missions to Halley's comet in 1985-86 are described. A large scientific return would be acquired from a ballistic Halley intercept in spite of the high flyby speeds that are associated with this mission mode. The possibility of retargeting the cometary spacecraft to additional comets after the Halley intercept also exists. Two cometary spacecraft of identical design would be used to carry out four separate cometary encounters over a 3 year period. One spacecraft would intercept Halley's comet before its perihelion passage in December 1985 and then go on to comet Borrelly with an encounter in January 1988. The other spacecraft would be targeted for a postperihelion Halley intercept in March 1986 before proceeding toward an encounter with comet Tempel 2 in September 1988.

  18. Unified semiclassical approach to electronic transport from diffusive to ballistic regimes

    NASA Astrophysics Data System (ADS)

    Geng, Hao; Deng, Wei-Yin; Ren, Yue-Jiao; Sheng, Li; Xing, Ding-Yu

    2016-09-01

    We show that by integrating out the electric field and incorporating proper boundary conditions, a Boltzmann equation can describe electron transport properties, continuously from the diffusive to ballistic regimes. General analytical formulas of the conductance in D = 1,2,3 dimensions are obtained, which recover the Boltzmann-Drude formula and Landauer-Büttiker formula in the diffusive and ballistic limits, respectively. This intuitive and efficient approach can be applied to investigate the interplay of system size and impurity scattering in various charge and spin transport phenomena, when the quantum interference effect is not important. Project supported by the National Basic Research Program of China (Grant Nos. 2015CB921202 and 2014CB921103) and the National Natural Science Foundation of China (Grant No. 11225420).

  19. Planetary Moon Cycler Trajectories

    NASA Technical Reports Server (NTRS)

    Russell, Ryan P.; Strange, Nathan J.

    2007-01-01

    Free-return cycler trajectories repeatedly shuttle a spacecraft between two bodies using little or no fuel. Here, the cycler architecture is proposed as a complementary and alternative method for designing planetary moon tours. Previously applied enumerative cycler search and optimization techniques are generalized and specifically implemented in the Jovian and Saturnian moon systems. In addition, the algorithms are tested for general use to find non-Earth heliocentric cyclers. Overall, hundreds of ideal model ballistic cycler geometries are found and several representative cases are documented and discussed. Many of the ideal model solutions are found to remain ballistic in a zero radius sphere of influence patched conic ephemeris model, and preliminary work in a high-fidelity fully integrated model demonstrates near-ballistic cycles for several example cases.

  20. Determination of the propellant combustion law under ballistic experiment conditions

    NASA Astrophysics Data System (ADS)

    Ishchenko, A. N.; Diachkovskii, A. S.; Zykova, A. I.; Kasimov, VZ; Samorokova, N. M.

    2017-11-01

    The main characteristics of ballistic experiment are the maximum pressure in the combustion chamber P max and the projectile velocity at the time of barrel leaving U M. During the work the burning law of the new high-energy fuel was determined in a ballistic experiment. This burning law was used for a parametric study of depending P max and U M from a powder charge mass and a traveling charge at initial temperature of + 20 °C was carried out. The optimal conditions for loading were obtained for improving the muzzle velocity by 14.9 %. Under optimal loading, there is defined the conditions, which is possible to get the greatest value muzzle velocity projectile at pressures up to 600 MPa.

  1. HVI Ballistic Limit Charaterization of Fused Silica Thermal Pane

    NASA Technical Reports Server (NTRS)

    Bohl, William E.; Miller, Joshua E.; Christiansen, Eric L.; Deighton, Kevin.; Davis, Bruce

    2015-01-01

    The Orion spacecraft's windows are exposed to the micrometeroid and orbital debris (MMOD) space environments while in space as well as the Earth entry environment at the mission's conclusion. The need for a low-mass spacecraft window design drives the need to reduce conservatism when assessing the design for loss of crew due to MMOD impact and subsequent Earth entry. Therefore, work is underway at NASA and Lockheed Martin to improve characterization of the complete penetration ballistic limit of an outer fused silica thermal pane. Hypervelocity impact tests of the window configuration at up to 10 km/s and hydrocode modeling have been performed with a variety of projectile materials to enable refinement of the fused silica ballistic limit equation.

  2. Mechanical properties of silicone based composites as a temperature insensitive ballistic backing material for quantifying back face deformation.

    PubMed

    Edwards, Tara D; Bain, Erich D; Cole, Shawn T; Freeney, Reygan M; Halls, Virginia A; Ivancik, Juliana; Lenhart, Joseph L; Napadensky, Eugene; Yu, Jian H; Zheng, James Q; Mrozek, Randy A

    2018-04-01

    This paper describes a new witness material for quantifying the back face deformation (BFD) resulting from high rate impact of ballistic protective equipment. Accurate BFD quantification is critical for the assessment and certification of personal protective equipment, such as body armor and helmets, and ballistic evaluation. A common witness material is ballistic clay, specifically, Roma Plastilina No. 1 (RP1). RP1 must be heated to nearly 38°C to pass calibration, and used within a limited time frame to remain in calibration. RP1 also exhibits lot-to-lot variability and is sensitive to time, temperature, and handling procedures, which limits the BFD accuracy and reproducibility. A new silicone composite backing material (SCBM) was developed and tested side-by-side with heated RP1 using quasi-static indentation and compression, low velocity impact, spherical projectile penetration, and both soft and hard armor ballistic BFD measurements to compare their response over a broad range of strain rates and temperatures. The results demonstrate that SCBM mimics the heated RP1 response at room temperature and exhibits minimal temperature sensitivity. With additional optimization of the composition and processing, SCBM could be a drop-in replacement for RP1 that is used at room temperature during BFD quantification with minimal changes to the current RP1 handling protocols and infrastructure. It is anticipated that removing the heating requirement, and temperature-dependence, associated with RP1 will reduce test variability, simplify testing logistics, and enhance test range productivity. Published by Elsevier B.V.

  3. Effect of ageing on the calibration of ballistic gelatin.

    PubMed

    Guey, Jason; Rodrigues, S; Pullen, A; Shaw, B; Kieser, D C

    2018-02-27

    Ballistic gelatin is commonly used as a validated surrogate for soft tissue during terminal ballistic testing. However, the effect of a delay between production and testing of a gelatin mould remains unknown. The aim of this study was to determine any potential effects of ageing on ballistic gelatin. Depth of penetration (DoP) of 4.5 mm spherical fragment simulating projectiles was ascertained using mixtures of 10%, 11.25% and 20% Type A 250 Bloom ballistic gelatin. Testing was performed daily for 5 days using velocities between 75 and 210 m/s. DoP at day 5 was statistically compared with day 1, and net mass change was recorded daily. No significant difference was found for DoP observed with time in any of the samples (P>0.05). Spearman correlation was excellent in all moulds. The moulds with known standard calibrations remained in calibration throughout the study period. Mass loss of less than 1% was noted in all samples. Mass loss was the only quantifiable measure of changes in the blocks with time, but did not correlate with any changes in DoP. This may provide reassurance when undertaking such testing that an inadvertent delay will not significantly alter the penetration properties of the mould. Future research is recommended to determine any potential effect on the mechanical properties of gelatin at higher velocity impacts and whether the calibration corresponds to an adequate simulation under such conditions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  4. Myths and Misinformation About Gunshot Wounds may Adversely Affect Proper Treatment.

    PubMed

    Hafertepen, Stephen C; Davis, James W; Townsend, Ricard N; Sue, Lawrence P; Kaups, Krista L; Cagle, Kathleen M

    2015-07-01

    Poorly designed experiments and popular media have led to multiple myths about wound ballistics. Some of these myths have been incorporated into the trauma literature as fact and are included in Advanced Trauma Life Support (ATLS). We hypothesized that these erroneous beliefs would be prevalent, even among those providing care for patients with gunshot wounds (GSWs), but could be addressed through education. ATLS course content was reviewed. Several myths involving wound ballistics were identified. Clinically relevant myths were chosen including wounding mechanism, lead poisoning, debridement, and antibiotic use. Subsequently, surgery and emergency medicine services at three different trauma centers were studied. All three sites were busy, urban trauma centers with a significant amount of penetrating trauma. A pre-test was administered prior to a lecture on wound ballistics followed by a post-test. Pre- and post-test scores were compared and correlated with demographic data including ATLS course completion, firearm/ballistics experience, and years of post-graduate medical experience (PGME). One-hundred and fifteen clinicians participated in the study. A mean pre-test score of 34 % improved to 78 % on the post-test with associated improvements in all areas of knowledge (p < 0.001). Years of PGME correlated with higher pre-test score (p = 0.021); however, ATLS status did not (p = 0.774). Erroneous beliefs involving wound ballistics are prevalent even among clinicians who frequently treat victims of GSWs and could lead to inappropriate treatment. Focused education markedly improved knowledge. The ATLS course and manual promulgate some of these myths and should be revised.

  5. Computational and experimental models of the human torso for non-penetrating ballistic impact.

    PubMed

    Roberts, J C; Merkle, A C; Biermann, P J; Ward, E E; Carkhuff, B G; Cain, R P; O'Connor, J V

    2007-01-01

    Both computational finite element and experimental models of the human torso have been developed for ballistic impact testing. The human torso finite element model (HTFEM), including the thoracic skeletal structure and organs, was created in the finite element code LS-DYNA. The skeletal structure was assumed to be linear-elastic while all internal organs were modeled as viscoelastic. A physical human surrogate torso model (HSTM) was developed using biosimulant materials and the same anthropometry as the HTFEM. The HSTM response to impact was recorded with piezoresistive pressure sensors molded into the heart, liver and stomach and an accelerometer attached to the sternum. For experimentation, the HSTM was outfitted with National Institute of Justice (NIJ) Level I, IIa, II and IIIa soft armor vests. Twenty-six ballistic tests targeting the HSTM heart and liver were conducted with 22 caliber ammunition at a velocity of 329 m/s and 9 mm ammunition at velocities of 332, 358 and 430 m/s. The HSTM pressure response repeatability was found to vary by less than 10% for similar impact conditions. A comparison of the HSTM and HTFEM response showed similar pressure profiles and less than 35% peak pressure difference for organs near the ballistic impact point. Furthermore, the peak sternum accelerations of the HSTM and HTFEM varied by less than 10% for impacts over the sternum. These models provide comparative tools for determining the thoracic response to ballistic impact and could be used to evaluate soft body armor design and efficacy, determine thoracic injury mechanisms and assist with injury prevention.

  6. Solid-propellant rocket motor internal ballistics performance variation analysis, phase 5

    NASA Technical Reports Server (NTRS)

    Sforzini, R. H.; Murph, J. E.

    1980-01-01

    The results of research aimed at improving the predictability of internal ballistics performance of solid-propellant rocket motors (SRM's) including thrust imbalance between two SRM's firing in parallel are presented. Static test data from the first six Space Shuttle SRM's is analyzed using a computer program previously developed for this purpose. The program permits intentional minor design biases affecting the imbalance between any two SMR's to be removed. Results for the last four of the six SRM's, with only the propellant bulk temperature as a non-random variable, are generally within limits predicted by theory. Extended studies of internal ballistic performance of single SRM's are presented based on an earlier developed mathematical model which includes an assessment of grain deformation. The erosive burning rate law used in the model is upgraded and made more general. Excellent results are obtained in predictions of the performances of five different SRM's of quite different sizes and configurations. These SRM's all employ PBAN type propellants with ammonium perchlorate oxidizer and 16 to 20% aluminum except one which uses carboxyl terminated butadiene binder. The only non-calculated parameters in the burning rate equations that are changed for the different SRM's are the zero crossflow velocity burning rate coefficients and exponents. The results, in general, confirm the importance of grain deformation. The improved internal ballistic model makes practical development of an effective computer program for application of an optimization technique to SRM design which is also demonstrated. The program uses a pattern search technique to minimize the difference between a desired thrust-time trace and one calculated based on the internal ballistic model.

  7. Wound Ballistics Modeling for Blast Loading Blunt Force Impact and Projectile Penetration.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Taylor, Paul A.

    Light body armor development for the warfighter is based on trial-and-error testing of prototype designs against ballistic projectiles. Torso armor testing against blast is nonexistent but necessary to protect the heart and lungs. In tests against ballistic projectiles, protective apparel is placed over ballistic clay and the projectiles are fired into the armor/clay target. The clay represents the human torso and its behind-armor, permanent deflection is the principal metric used to assess armor protection. Although this approach provides relative merit assessment of protection, it does not examine the behind-armor blunt trauma to crucial torso organs. We propose a modeling andmore » simulation (M&S) capability for wound injury scenarios to the head, neck, and torso of the warfighter. We will use this toolset to investigate the consequences of, and mitigation against, blast exposure, blunt force impact, and ballistic projectile penetration leading to damage of critical organs comprising the central nervous, cardiovascular, and respiratory systems. We will leverage Sandia codes and our M&S expertise on traumatic brain injury to develop virtual anatomical models of the head, neck, and torso and the simulation methodology to capture the physics of wound mechanics. Specifically, we will investigate virtual wound injuries to the head, neck, and torso without and with protective armor to demonstrate the advantages of performing injury simulations for the development of body armor. The proposed toolset constitutes a significant advance over current methods by providing a virtual simulation capability to investigate wound injury and optimize armor design without the need for extensive field testing.« less

  8. Examining the Relationship Between Ballistic and Structural Properties of Lightweight Thermoplastic Unidirectional Composite Laminates

    DTIC Science & Technology

    2011-08-01

    Kevlar KM2® Style 705 PVB phenolic woven aramid composite was included. A developmental unidirectional thermoplastic aramid fiber, Honeywell...Examining the Relationship Between Ballistic and Structural Properties of Lightweight Thermoplastic Unidirectional Composite Laminates by...Unidirectional Composite Laminates Lionel R. Vargas-Gonzalez, Shawn M. Walsh, and James C. Gurganus Weapons and Materials Research Directorate, ARL

  9. Ballistic Missile Defense. Past and Future

    DTIC Science & Technology

    2010-04-01

    the Author” at the end of this book . x • Jacques S. Gansler even nuclear) are more likely than ballistic missile attacks, we should not waste ...Portions of this book may be quoted or reprinted without permission, provided that a standard source credit line is included...This book was published by the Center for Technology and National Security Policy, National Defense University, Fort Lesley J

  10. Conformable Self-Healing Ballistic Armor

    DTIC Science & Technology

    2011-06-28

    providing additional ballistic resistance . A closable filler opening 16 comprising a threaded wide mouth aperture with 50 a threaded stopper would be...quality of abrasive , high resistance to projectiles at a relatively light weight; thus, they represent a preferred particle composition for a filler...in resisting a plurality of projectiles 60 impacting on the same general area. SUMMARY OF THE INVENTION The present invention comprises a

  11. Australian DefenceScience. Volume 15, Number 3, Spring

    DTIC Science & Technology

    2007-01-01

    ignition, high pressure sealing, ignitor and propellent design, and ballistics instrumentation . Validation of simulation models of internal ballistics...supplementing visual information obtained by sources such as radiography and scanning electron microscopy, revealing details about features that are not...otherwise visible. Hence, it can assist with the inspection of vital component parts that are subject to high stresses, like aircraft engine turbine

  12. Stationarity conditions for physicochemical processes in the interior ballistics of a gun

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lipanov, A.M.

    1995-09-01

    An original method is proposed for ensuring time-invariant (stationary) interior ballistic parameters in the postprojectile space of a gun barrel. Stationarity of the parameters is achieved by investing the solid-propellant charge with highly original structures that produce the required pressure condition and linear growth of the projectile velocity. Simple relations are obtained for calculating the principal characteristics.

  13. Time-reversed, flow-reversed ballistics simulations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zernow, L.; Chapyak, E. J.; Scheffler, D. R.

    2001-01-01

    Two-dimensional simulations of planar sheet jet formation are studied to examine the hydrodynamic issues involved when simulations are carried out in the inverse direction, that is, with reversed time and flow. Both a realistic copper equation of state and a shockless equation of state were used. These studies are an initial step in evaluating this technique as a ballistics design tool.

  14. Early Rockets

    NASA Image and Video Library

    1953-08-30

    U.S. Army Redstone Rocket: The Redstone ballistic missile was a high-accuracy, liquid-propelled, surface-to-surface missile developed by the Army Ballistic Missile Agency, Redstone Arsenal, in Huntsville, Alabama, under the direction of Dr. von Braun. The Redstone rocket was also known as "Old Reliable" because of its many diverse missions. The first Redstone Missile was launched from Cape Canaveral, Florida on August 30, 1953.

  15. Fire Support Team Experiment.

    DTIC Science & Technology

    1984-12-01

    December 1984 APPROVED FOR PUBUC RELEASE; DISTRIBUTION UNLIMITED. U_ US ARMY *’ HUMAN ENGINEERING LABORATORY US ARMY BALLISTIC RESEARCH LABORATORY ABERDEEN...INTRODUCTION A. Background In March 1982, the HELBAT ( Human Engineering Laboratory Battalion Artillery Test) Executive Committee agreed that the Ballistic...tactical equipment and its -. human operators. FOSCE mimicked the actions of the platoon forward observers that work for the FIST HQ while the FDS

  16. Penaid Nonproliferation: Hindering the Spread of Countermeasures Against Ballistic Missile Defenses

    DTIC Science & Technology

    2014-01-01

    50 Penaid Nonproliferation: Hindering the Spread of Countermeasures Against Ballistic Missile Defenses 42 /2010! Plume Signature Control...and Richard Speier, “Penaid Nonproliferation: Analysis and Recommendations,” briefing, Veridian Corp., Arlington, Va., June 29, 2000. “ Missile ...is a nonprofit institution that helps improve policy and decisionmaking through research and analysis . This electronic document was made available

  17. Optimized digital filtering techniques for radiation detection with HPGe detectors

    NASA Astrophysics Data System (ADS)

    Salathe, Marco; Kihm, Thomas

    2016-02-01

    This paper describes state-of-the-art digital filtering techniques that are part of GEANA, an automatic data analysis software used for the GERDA experiment. The discussed filters include a novel, nonlinear correction method for ballistic deficits, which is combined with one of three shaping filters: a pseudo-Gaussian, a modified trapezoidal, or a modified cusp filter. The performance of the filters is demonstrated with a 762 g Broad Energy Germanium (BEGe) detector, produced by Canberra, that measures γ-ray lines from radioactive sources in an energy range between 59.5 and 2614.5 keV. At 1332.5 keV, together with the ballistic deficit correction method, all filters produce a comparable energy resolution of 1.61 keV FWHM. This value is superior to those measured by the manufacturer and those found in publications with detectors of a similar design and mass. At 59.5 keV, the modified cusp filter without a ballistic deficit correction produced the best result, with an energy resolution of 0.46 keV. It is observed that the loss in resolution by using a constant shaping time over the entire energy range is small when using the ballistic deficit correction method.

  18. On the suitability of Synbone® as a tissue simulant

    NASA Astrophysics Data System (ADS)

    Appleby-Thomas, Gareth; Fitzmaurice, Brianna; Hameed, Amer; Wood, David; Gibson, Mike; Painter, Jonathan

    2015-06-01

    The applicability of various materials as human tissue analogues has been a topic of increasing interest in recent years. It allows for more cost-effective experiments to be carried out, but also avoids ethical issues that would arise from using real human tissue. Synbone® , a porous polyurethane material, is commonly used in ballistic experiments as a bone simulant, but until now has not been characterised in terms of its dynamic behaviour. Here, the Hugoniot equation-of-state (EOS) for Synbone® has been derived via a series of plate-impact experiments; highlighting the importance of the underlying material structure in terms of material collapse under high strain-rates. A series of ballistic tests were also undertaken to provide further insight into the ballistic response of Synbone® and its potential role as a tissue simulant. This work - following on from previous in-house studies of other tissue analogues - has provided useful data for future simulation of this material. In addition, comparison to dynamic data for other tissue and simulant materials has highlighted the importance of considering tissue as non-monolithic; each layer of tissue should ideally be represented by its own simulant in ballistic experiments.

  19. Experimental observation of ballistic nanofriction on graphene

    NASA Astrophysics Data System (ADS)

    Blue, Brandon; Lodge, Michael; Tang, Chun; Hubbard, William; Martini, Ashlie; Dawson, Ben; Ishigami, Masa

    Recent calculations have predicted that gold nanocrystals slide on graphite with two radically different friction coefficients depending on their speeds. At high sliding speeds in the range of 100?m/s, nanocrystals are expected to behave radically differently in what is known as the ballistic nanofriction regime. In this work, we present a direct measurement of ballistic nanofriction for gold nanocrystals on graphene. Nanocrystals are deposited onto an oscillating graphene-coated quartz crystal microbalance (QCM) in-situ under UHV and allowed to periodically ring down. After deposition, frictional parameters are measured as a function of oscillatory velocity to investigate the predicted velocity dependence of friction. Lubricity beyond even the predictions of ballistic nanofriction is observed at much lower surface velocities than expected, with drag coefficients approaching 8.65*10-14 kg/s. In comparison to the theoretically-predicted value of 2.0*10-13 kg/s, our results suggest a much lower interaction strength than proposed in contemporary models of nanoscopic sliding contacts even at relatively low speeds. This work is based on research supported by the National Science Foundation, Grant No. 0955625 (MLS, BTB, BDD and MI) and Grant No. CMMI-1265594 (CT and AM). BDD and MI were also supported by the Intelligence Community Postdoctoral Fellowship.

  20. [Ballistic concepts and management of gunshot wounds at members].

    PubMed

    Fabeck, L; Hock, N; Goffin, J; Ngatchou, W

    2017-01-01

    Ballistic trauma is not the prerogative of battlefields and currently extends to civil environments. Any surgeon or emergency room can be faced with such trauma whose management requires an understanding of wound ballistics. The aim of this retrospective is reviewing the management of ballistic trauma within the C.H.U. Saint-Pierre hospital over a period of ten years. Data recorded included demographics data, lesions, clinical parameters, imaging, treatment and outcome. It appears that the wounds of the members have a low mortality rate but a significant rate of complications. Patients should be managed according to the ATLS protocol and according hemodynamic stability and location of the injury, benefit from imaging. Unstable patients will be operated in emergency, stable patients will be treated according to the extent of damage and the type of fracture either conservatively or by external fixator and intramedullary centromedullary. Debridement and antibiotics are recommended as a nerve exploration if there is a peripheral paralysis. The management of trauma in our sample appear not optimal in light of the literature especially in terms of setting the vascular point of debridement, antibiotic and nerve repair resulting in significant consequences. Two management protocols according to patients' hemodynamic status are offered.

  1. Valley-symmetric quasi-1D transport in ballistic graphene

    NASA Astrophysics Data System (ADS)

    Lee, Hu-Jong

    We present our recent studies on gate-defined valley-symmetric one-dimensional (1D) carrier guiding in ballistic monolayer graphene and valley-symmetry-protected topological 1D transport in ballistic bilayer graphene. Successful carrier guiding was realized in ballistic monolayer graphene even in the absence of a band gap by inducing a high distinction ( more than two orders of magnitude) in the carrier density between the region of a quasi-1D channel and the rest of the top-gated regions. Conductance of a channel shows quantized values in units of 4e2/ h, suggesting that the valley symmetry is preserved. For the latter, the topological 1D conduction was realized between two closely arranged insulating regions with inverted band gaps, induced under a pair of split dual gating with polarities opposite to each other. The maximum conductance along the boundary channel showed 4e2/ h, again with the preserved valley symmetry. The 1D topological carrier guiding demonstrated in this study affords a promising route to robust valleytronic applications and sophisticated valley-associated functionalities based on 2D materials. This work was funded by the National Research Foundation of Korea.

  2. Impact Resistance of Lightweight Hybrid Structures for Gas Turbine Engine Fan Containment Applications

    NASA Technical Reports Server (NTRS)

    Hebsur, Mohan G.; Noebe, Ronald D.; Revilock, Duane M.

    2003-01-01

    The ballistic impact resistance of hybrid composite sandwich structures was evaluated with the ultimate goal of developing new materials or structures for potential gas turbine engine fan containment applications. The sandwich structures investigated consisted of GLARE-5 laminates as face sheets with lightweight cellular metallic materials such as honeycomb, foam, and lattice block as a core material. The impact resistance of these hybrid sandwich structures was compared to GLARE-5 laminates and 2024-T3 Al sheet, which were tested as a function of areal weight (material thickness). The GLARE-5 laminates exhibited comparable impact properties to that of 2024-T3 Al at low areal weights, even though there were significant differences in the static tensile properties of these materials. The GLARE-5, however, did have a greater ballistic limit than straight aluminum sheet at higher areal weights. Furthermore, there is up to a 25% advantage in ballistic limit for the GLARE-5/foam sandwich structures compared to straight 2024-T3 Al. But no advantage in ballistic limit was observed between any of the hybrid sandwich structures and thicker versions of GLARE-5. Recommendations for future work are provided, based on these preliminary data.

  3. Quantum ballistic transport in strained epitaxial germanium

    NASA Astrophysics Data System (ADS)

    Gul, Y.; Holmes, S. N.; Newton, P. J.; Ellis, D. J. P.; Morrison, C.; Pepper, M.; Barnes, C. H. W.; Myronov, M.

    2017-12-01

    Large scale fabrication using Complementary Metal Oxide Semiconductor compatible technology of semiconductor nanostructures that operate on the principles of quantum transport is an exciting possibility now due to the recent development of ultra-high mobility hole gases in epitaxial germanium grown on standard silicon substrates. We present here a ballistic transport study of patterned surface gates on strained Ge quantum wells with SiGe barriers, which confirms the quantum characteristics of the Ge heavy hole valence band structure in 1-dimension. Quantised conductance at multiples of 2e2/h is a universal feature of hole transport in Ge up to 10 × (2e2/h). The behaviour of ballistic plateaus with finite source-drain bias and applied magnetic field is elucidated. In addition, a reordering of the ground state is observed.

  4. Ballistic mode Mercury orbiter missions.

    NASA Technical Reports Server (NTRS)

    Hollenbeck, G. R.

    1973-01-01

    The MVM'73 Mercury flyby mission will initiate exploration of this unique planet. No firm plans for follow-on investigations have materialized due to the difficult performance requirements of the next logical step, an orbiter mission. Previous investigations of ballistic mode flight opportunities have indicated requirements for a Saturn V class launch vehicle. Consequently, most recent effort has been oriented to use of solar electric propulsion. More comprehensive study of the ballistic flight mode utilizing Venus gravity-assist has resulted in identification of timely high-performance mission opportunities compatible with programmed launch vehicles and conventional spacecraft propulsion technologies. A likely candidate for an initial orbiter mission is a 1980 opportunity which offers net orbiter spacecraft mass of about 435 kg with the Titan IIIE/Centaur launch vehicle and single stage solid propulsion for orbit insertion.

  5. Analytic theory of orbit contraction and ballistic entry into planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Longuski, J. M.; Vinh, N. X.

    1980-01-01

    A space object traveling through an atmosphere is governed by two forces: aerodynamic and gravitational. On this premise, equations of motion are derived to provide a set of universal entry equations applicable to all regimes of atmospheric flight from orbital motion under the dissipate force of drag through the dynamic phase of reentry, and finally to the point of contact with the planetary surface. Rigorous mathematical techniques such as averaging, Poincare's method of small parameters, and Lagrange's expansion, applied to obtain a highly accurate, purely analytic theory for orbit contraction and ballistic entry into planetary atmospheres. The theory has a wide range of applications to modern problems including orbit decay of artificial satellites, atmospheric capture of planetary probes, atmospheric grazing, and ballistic reentry of manned and unmanned space vehicles.

  6. Tests of protective clothing for the safe handling of pressurized lamps

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.

    1975-01-01

    Tests were made to find a clothing material combination for use in handling high-pressure lamps. Monofilament nylon, ballistic nylon, and ballistic felt grouped into various multilayer combinations and chromed leather were positioned around and 30 cm (12 in.) away from exploding high-pressure lamps of different manufacturers and wattages. The results are: (1) 5024 nylon/ballistic felt/5024 nylon in a layered configuration was not penetrated by fragments of lamps as large as 6.5 kW; (2) this layered combination is lightweight and pliable and offers greater mobility and comfort to the user than previous protective clothing; and (3) Lexan plastic 1.6 mm (1/6 in.) thick to be used for face shield material showed no penetration for lamps as large as 20 kW.

  7. A model for wind-extension of the Copernicus ejecta blanket

    NASA Technical Reports Server (NTRS)

    Rehfuss, D. E.; Michael, D.; Anselmo, J. C.; Kincheloe, N. K.

    1977-01-01

    The interaction between crater ejecta and the transient wind from impact-shock vaporization is discussed. Based partly on Shoemaker's (1962) ballistic model of the Copernicus ejecta and partly on Rehfuss' (1972) treatment of lunar winds, a simple model is developed which indicates that if Copernicus were formed by a basaltic meteorite impacting at 20 km/s, then 3% of the ejecta mass would be sent beyond the maximum range expected from purely ballistic trajectories. That 3% mass would, however, shift the position of the outer edge of the ejecta blanket more than 400% beyond the edge of the ballistic blanket. For planetary bodies lacking an intrinsic atmosphere, the present model indicates that this form of hyperballistic transport can be very significant for small (no more than about 1 kg) ejecta fragments.

  8. The Clinton plan for theater missile defenses: Costs and alternatives

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mosher, D.; Hall, R.

    1994-09-01

    Since the Gulf War, the Department of Defense has placed a high priority on developing defenses against theater ballistic missiles (TBMs). Over the past two years the Clinton administration has redirected the focus of the Ballistic Missile Organization (BMDO, formerly the Strategic Defense Initiative Organization) away from a national missile defense system and toward the development of theater missile defenses (TMDs). But the plan put forward by the administration is expensive - as much as $50 billion through the year 2010 - and it also raises several important issues about compliance with the Anti-Ballistic Missile (ABM) Treaty. But other approachesmore » to TMD would address some of these cost and compliance concerns, so it is worthwhile to look at several alternatives and analyze their costs and effects on capability.« less

  9. Multi-hierarchical movements in self-avoiding walks

    NASA Astrophysics Data System (ADS)

    Sakiyama, Tomoko; Gunji, Yukio-Pegio

    2017-07-01

    A self-avoiding walk (SAW) is a series of moves on a lattice that visit the same place only once. Several studies reported that repellent reactions of foragers to previously visited sites induced power-law tailed SAWs in animals. In this paper, we show that modelling the agent's multi-avoidance reactions to its trails enables it to show ballistic movements which result in heavy-tailed movements. There is no literature showing emergent ballistic movements in SAWs. While following SAWs, the agent in my model changed its reactions to marked patches (visited sites) by considering global trail patterns based on local trail patterns when the agent was surrounded by previously visited sites. As a result, we succeeded in producing ballistic walks by the agents which exhibited emergent power-law tailed movements.

  10. A ballistic two-dimensional-electron-gas Andreev interferometer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Amado, M., E-mail: mario.amadomontero@sns.it; Fornieri, A.; Sorba, L.

    2014-06-16

    We report the realization and investigation of a ballistic Andreev interferometer based on an InAs two dimensional electron gas coupled to a superconducting Nb loop. We observe strong magnetic modulations in the voltage drop across the device due to quasiparticle interference within the weak-link. The interferometer exhibits flux noise down to ∼80 μΦ{sub 0}/√(Hz) and a robust behavior in temperature with voltage oscillations surviving up to ∼7 K. Besides this remarkable performance, the device represents a crucial first step for the realization of a fully-tunable ballistic superconducting magnetometer and embodies a potential advanced platform for the investigation of Majorana bound states, non-localmore » entanglement of Cooper pairs, as well as the manipulation and control of spin triplet correlations.« less

  11. Contemporary body armor: technical data, injuries, and limits.

    PubMed

    Prat, N; Rongieras, F; Sarron, J-C; Miras, A; Voiglio, E

    2012-04-01

    The introduction of firearms in the fifteenth century led to the continuous development of bulletproof personal protection. Due to recent industrial progress and the emergence of a new generation of ballistic fibers in the 1960s, the ability of individual ballistic protections to stop projectiles greatly increased. While protective equipment is able to stop increasingly powerful missiles, deformation during the impact can cause potentially lethal nonpenetrating injuries that are grouped under the generic term of behind armor blunt trauma, and the scope and consequences of these are still unclear. This review first summarizes current technical data for modern bulletproof vests, the materials used in them, and the stopping mechanisms they employ. Then it describes recent research into the specific ballistic injury patterns of soldiers wearing body armor, focusing on behind-armor blunt trauma.

  12. Innovative 3D Textile Structures for Soft Body Armor Protection: The EPIDARM Project

    NASA Astrophysics Data System (ADS)

    Maillet, Jérôme; Lefebvre, Marie; Boussu, François; Pirlot, Marc

    There is a real need for battlefield soldiers to be protected from ­ballistic and CBRNE threats and also to be in permanent contact and localization with the logistic support of the commander. Ballistic, CBRNE and tactical jackets are currently three different components, developed separately and worn on top of each other. One of the EPIDARM project's targets is to propose a personal protection demonstration for the optimal system configuration in order to reduce the cost and weight while improving protection. The systems approach used for the EPIDARM program considers the protective system inside its environment (threat, the wearer - generic soldier, task and climates). The latest emergent technologies in ballistic and CBRN protection, ergonomic effectiveness and financial cost are considered and help to select final solutions.

  13. Military Power of the People’s Republic of China, 2009

    DTIC Science & Technology

    2009-01-01

    executed for taking bribes to approve fake drugs. Environment . China’s economic development has come at a significant environmental cost...Satellite ASEAN : Association of Southeast Asian Nations ASEM: Asia-Europe Meeting ASBM: Anti-Ship Ballistic Missile ASCM: Anti-Ship Cruise Missile ASM...Operational Capability IRBM: Intermediate-Range Ballistic Missile LACM: Land Attack Cruise Missile LEO: Low Earth Orbit MaRV: Maneuvering Re- entry Vehicle

  14. Navy Columbia Class (Ohio Replacement) Ballistic Missile Submarine (SSBN[X]) Program: Background and Issues for Congress

    DTIC Science & Technology

    2016-10-25

    program, a program to design and build a new class of 12 ballistic missile submarines (SSBNs) to replace the Navy’s current force of 14 Ohio-class SSBNs...billion in detailed design and nonrecurring engineering (DD/NRE) costs for the entire class, and $8.8 billion in construction costs for the ship... Design ................................................................................................................. 8 Program Cost

  15. Heterojunction Solid-State Devices for Millimeter-Wave Sources.

    DTIC Science & Technology

    1983-10-01

    technology such as MBE and/or OK-CVD will be required. Our large-signal, numerical WATT device simulations are the first to predict from basic transport...results are due to an improved method for determining semiconductor material parameters. We use a theoretical Monte Carlo materials simulation ... simulations . These calculations have helped provide insight into velocity overshoot and ballistic transport phenomena. We find that ballistic or near

  16. Novel Methods in Terminal Ballistics and Mechanochemistry of Damage 2. Phenomenological Mechanochemistry of Damage in Solid Brittle Dielectrics

    DTIC Science & Technology

    2015-09-01

    Phenomenological Mechanochemistry of Damage in Solid Brittle Dielectrics by MA Grinfeld Approved for public release...Army Research Laboratory Novel Methods in Terminal Ballistics and Mechanochemistry of Damage 2. Phenomenological Mechanochemistry of Damage...2. Phenomenological Mechanochemistry of Damage in Solid Brittle Dielectrics 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER

  17. Cost Effective Regional Ballistic Missile Defense

    DTIC Science & Technology

    2016-02-16

    deploying advanced air defense systems18, such as the Russian S-300 and S-500, and concealing them in hardened, camouflaged sites, such as extensive... Russian objections to the European Phased Adaptive Approach (EPAA) and fund homeland defense priorities.39 Furthermore, the PTSS system was also... Theatre Ballistic Missile Defence Capability Becomes Operational,” Jane’s Missiles & Rockets, 1 February 2011. 55 Joseph W. Kirschbaum, REGIONAL MISSILE

  18. The Full Costs of Ballistic Missile Defense

    DTIC Science & Technology

    2003-01-01

    following words: “We assess that countries developing ballistic missiles would also develop various responses to US theater and national defenses. Russia...and China each have developed numerous countermeasures and probably are willing to sell the requisite technologies. • Many countries , such as North...penetration aids and countermeasures. • These countries could develop countermeasures based on these technologies by the time they flight test their missiles

  19. Effect of concentric and eccentric velocity during heavy-load non-ballistic elbow flexion resistance exercise.

    PubMed

    Sampson, John A; Donohoe, Alison; Groeller, Herbert

    2014-05-01

    Mechanical and neuromuscular benefits arise during ballistic stretch-shortening cycle muscle activation, yet resistance training regimens are typically non-ballistic, and in contrast to ballistic movement, require a concentric deceleration phase. Twelve healthy males performed a unilateral, six repetition maximum non-ballistic elbow flexion-extension task during; (i) rapid shortening (RS), (ii) stretch-shortening cycle (SSC) and (iii) a 2-s eccentric and 2-s concentric control (C). A load cell and shaft encoder recorded respectively force and velocity. Surface electromyographic root mean square amplitude (EMGRMS) was recorded in the biceps and triceps brachii, and is reported as the relative (%) difference, normalised to control (C). The average lengthening and shortening velocity of SSC (0.57 ± 0.03 ms(-1); 0.43 ± 0.02 ms(-1)) was significantly greater than RS (0.22 ± 0.01 ms(-1); 0.35 ± 0.01 ms(-1)), and C (0.17 ± 0.00 ms(-1), 0.20 ± 0.00 ms(-1)). Peak eccentric force was increased (P<0.0001) and in the first 5% of concentric movement during SSC, in the first and last repetitions respectively (194.7 ± 8.4N, 164.1 ± 7.5 N) when compared to RS (163.3 ± 8.9 N, 152.4 ± 7.5 N) and C (155.9 ± 8.5 N, 152.2 ± 8.7 N). Eccentric EMGRMS in the biceps brachii was significantly increased during the first three and final repetitions of SSC (31.9 ± 10.9%, 46.7 ± 12.4, 69.3 ± 13.6%, 92.0 ± 16.4%), and the third and last repetitions of RS (35.9 ± 7.4%, 50.3 ± 10.9%), compared to C (0.00%, 15.8 ± 4.0%, 23.7 ± 4.1%, 39.2 ± 8.6%). In the current study, eccentric limb velocity potentiated eccentric and concentric force, concentric velocity, and eccentric EMG amplitude during non-ballistic exercise. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  20. Hybrid carbon-glass fiber/toughened epoxy thick composites subject to drop-weight and ballistic impacts

    NASA Astrophysics Data System (ADS)

    Sevkat, Ercan

    The goals of this study are to investigate the low velocity and ballistic impact response of thick-section hybrid fiber composites at room temperature. Plain-woven S2-Glass and IM7 Graphite fabrics are chosen as fiber materials reinforcing the SC-79 epoxy. Four different types of composites consisting of alternating layers of glass and graphite woven fabric sheets are considered. Tensile tests are conducted using 98 KN (22 kip) MTS testing machine equipped with environmental chamber. Low-velocity impact tests are conducted using an Instron-Dynatup 8250 impact test machine equipped with an environmental chamber. Ballistic impact tests are performed using helium pressured high-speed gas-gun. Tensile tests results were used to define the material behavior of the hybrid and non-hybrid composites in Finite Element modeling. The low velocity and ballistic impact tests showed that hybrid composites performance was somewhere between non-hybrid woven composites. Using woven glass fabrics as outer skin improved the impact performance of woven graphite composite. However hybrid composites are prone to delamination especially between dissimilar layers. The ballistic limit velocity V50 hybrid composites were higher that of woven graphite composite and lower than that of woven glass composite. Both destructive cross-sectional micrographs and nondestructive ultrasonic techniques are used to evaluate the damage created by impact. The Finite Element code LS-DYNA is chosen to perform numerical simulations of low velocity and ballistic impact on thick-section hybrid composites. The damage progression in these composites shows anisotropic nonlinearity. The material model to describe this behavior is not available in LS-DYNA material library. Initially, linear orthotropic material with damage (Chan-Chan Model) is employed to simulate some of the experimental results. Then, user-defined material subroutine is incorporated into LS-DYNA to simulate the nonlinear behavior. The experimentally obtained force-time histories, strain-time histories and damage patterns of impacted composites are compared with Finite element results. The results indicate that LS-DYNA could simulate the impact responses with sufficient accuracy once proper material models and boundary conditions are defined.

  1. Force-velocity properties' contribution to bilateral deficit during ballistic push-off.

    PubMed

    Samozino, Pierre; Rejc, Enrico; di Prampero, Pietro Enrico; Belli, Alain; Morin, Jean-Benoît

    2014-01-01

    The objective of this study is to quantify the contribution of the force-velocity (F-v) properties to bilateral force deficit (BLD) in ballistic lower limb push-off and to relate it to individual F-v mechanical properties of the lower limbs. The F-v relation was individually assessed from mechanical measurements for 14 subjects during maximal ballistic lower limb push-offs; its contribution to BLD was then investigated using a theoretical macroscopic approach, considering both the mechanical constraints of movement dynamics and the maximal external capabilities of the lower limb neuromuscular system. During ballistic lower limb push-off, the maximum force each lower limb can produce was lower during bilateral than unilateral actions, thus leading to a BLD of 36.7% ± 5.7%. The decrease in force due to the F-v mechanical properties amounted to 19.9% ± 3.6% of the force developed during BL push-offs, which represents a nonneural contribution to BLD of 43.5% ± 9.1%. This contribution to BLD that cannot be attributed to changes in neural features was negatively correlated to the maximum unloaded extension velocity of the lower limb (r = -0.977, P < 0.001). During ballistic lower limb push-off, BLD is due to both neural alterations and F-v mechanical properties, the latter being associated with the change in movement velocity between bilateral and unilateral actions. The level of the contribution of the F-v properties depends on the individual F-v mechanical profile of the entire lower limb neuromuscular system: the more the F-v profile is oriented toward velocity capabilities, the lower the loss of force from unilateral to bilateral push-offs due to changes in movement velocity.

  2. Influence of ballistic bench press on upper body power output in professional rugby players.

    PubMed

    West, Daniel J; Cunningham, Daniel J; Crewther, Blair T; Cook, Christian J; Kilduff, Liam P

    2013-08-01

    The use of heavy resistance exercise provides an effective preload stimulus for inducing postactivation potentiation (PAP) and increasing peak power output (PPO). However, this approach has limited application in many sporting situations (e.g., incorporation in a precompetition warm-up); and therefore, more practical strategies for inducing PAP need to be investigated. The aim of the present study was to compare the PPO changes after performing a preload stimulus of either a ballistic exercise or a traditional heavy resistance exercise. Twenty professional rugby union players completed 3 testing sessions, each separated by 48 hours. On the first occasion, subjects underwent a 3 repetition maximum (3RM)-bench press testing session. On the next 2 occasions, subjects performed a ballistic bench throw at baseline (30% of 1RM), followed by a preload stimulus of either heavy resistance training (HRT) (heavy bench press: 3 sets of 3 repetitions at 87% 1RM) or BBP (3 sets of 3 repetitions at 30% on 1RM) followed by ballistic bench throw after 8 minutes recovery. The trials were randomized and counterbalanced. Both preload stimuli protocols increased PPO compared with baseline (BBP baseline 892 ± 108 vs. 8 minutes 924 ± 119 W, p < 0.001; HRT baseline 893 ± 104 vs. 8 minutes 931 ± 116 W; p < 0.001). There were no conditional differences between PPO at 8 minutes (p = 0.141); moreover, the change in PPO from baseline was also similar between conditions (BBP Δ + 33 ± 18; HRT Δ + 38 ± 21 W; p = 0.112). In conclusion, a ballistic exercise provided an effective method of inducing PAP and increasing upper-body PPO; moreover, this elicited similar increases in PPO as a traditional heavy resistance exercise preloading stimulus.

  3. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel: A Computational Investigation

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Snipes, J. S.; Galgalikar, R.; Ramaswami, S.; Yavari, R.; Yen, C.-F.; Cheeseman, B. A.

    2014-09-01

    In our recent work, a multi-physics computational model for the conventional gas metal arc welding (GMAW) joining process was introduced. The model is of a modular type and comprises five modules, each designed to handle a specific aspect of the GMAW process, i.e.: (i) electro-dynamics of the welding-gun; (ii) radiation-/convection-controlled heat transfer from the electric-arc to the workpiece and mass transfer from the filler-metal consumable electrode to the weld; (iii) prediction of the temporal evolution and the spatial distribution of thermal and mechanical fields within the weld region during the GMAW joining process; (iv) the resulting temporal evolution and spatial distribution of the material microstructure throughout the weld region; and (v) spatial distribution of the as-welded material mechanical properties. In the present work, the GMAW process model has been upgraded with respect to its predictive capabilities regarding the spatial distribution of the mechanical properties controlling the ballistic-limit (i.e., penetration-resistance) of the weld. The model is upgraded through the introduction of the sixth module in the present work in recognition of the fact that in thick steel GMAW weldments, the overall ballistic performance of the armor may become controlled by the (often inferior) ballistic limits of its weld (fusion and heat-affected) zones. To demonstrate the utility of the upgraded GMAW process model, it is next applied to the case of butt-welding of a prototypical high-hardness armor-grade martensitic steel, MIL A46100. The model predictions concerning the spatial distribution of the material microstructure and ballistic-limit-controlling mechanical properties within the MIL A46100 butt-weld are found to be consistent with prior observations and general expectations.

  4. Optimization of Gas Metal Arc Welding (GMAW) Process for Maximum Ballistic Limit in MIL A46100 Steel Welded All-Metal Armor

    NASA Astrophysics Data System (ADS)

    Grujicic, M.; Ramaswami, S.; Snipes, J. S.; Yavari, R.; Yen, C.-F.; Cheeseman, B. A.

    2015-01-01

    Our recently developed multi-physics computational model for the conventional gas metal arc welding (GMAW) joining process has been upgraded with respect to its predictive capabilities regarding the process optimization for the attainment of maximum ballistic limit within the weld. The original model consists of six modules, each dedicated to handling a specific aspect of the GMAW process, i.e., (a) electro-dynamics of the welding gun; (b) radiation-/convection-controlled heat transfer from the electric arc to the workpiece and mass transfer from the filler metal consumable electrode to the weld; (c) prediction of the temporal evolution and the spatial distribution of thermal and mechanical fields within the weld region during the GMAW joining process; (d) the resulting temporal evolution and spatial distribution of the material microstructure throughout the weld region; (e) spatial distribution of the as-welded material mechanical properties; and (f) spatial distribution of the material ballistic limit. In the present work, the model is upgraded through the introduction of the seventh module in recognition of the fact that identification of the optimum GMAW process parameters relative to the attainment of the maximum ballistic limit within the weld region entails the use of advanced optimization and statistical sensitivity analysis methods and tools. The upgraded GMAW process model is next applied to the case of butt welding of MIL A46100 (a prototypical high-hardness armor-grade martensitic steel) workpieces using filler metal electrodes made of the same material. The predictions of the upgraded GMAW process model pertaining to the spatial distribution of the material microstructure and ballistic limit-controlling mechanical properties within the MIL A46100 butt weld are found to be consistent with general expectations and prior observations.

  5. Bullet fragmentation preceding a contour shot: case study and experimental simulation.

    PubMed

    Sterzik, V; Kneubuehl, B P; Bohnert, M; Riva, F; Glardon, M

    2017-01-01

    In medico-legal literature, only a small number of publications deal with lethal injuries caused by shots with modified guns. This might lead to the conclusion that such cases are extremely rare. However, there are cases again and yet again. During the investigation process, the modified gun is of particular importance since it can show an unusual ballistic behaviour. The present paper reports on a suicide of a 60-year-old man, committed with a modified revolver and a lead bullet. The man had a single gunshot wound with entrance at the right temporal bone. Autopsy revealed that the bullet had fragmented into two major parts. The smaller one stood outside the cranial cavity and pushed its way alongside between the cranial bone and scalp to its end position in the left temporal area. The bigger part entered the cranial cavity and ended in the left parietal lobe. In shots on ballistic soap and on a head-model, the ballistics of the weapon and lead bullet were characterized. The angle necessary for bullet fragmentation was determined by shots on ballistic soap and turned out to be 55°-60° at a velocity of around 200 m/s. This knowledge was transferred to contact shots on a head-model consisting of a layered polyurethane sphere filled with 10 % ballistic gelatine and covered with a skin-like cap almost all around. The resulting injury pattern corresponded to the one of the suicide person. The bigger bullet part entered the skull while the smaller part pushed its way alongside between skin and skull causing an outer contour shot. Furthermore, the revolver was documented firing off two bullets by one trigger pull-a phenomenon of importance for forensic casework the authors have not found reported in forensic literature.

  6. Modelling of dispersal and deposition of impact glass spherules from the Cretaceous-Tertiary boundary deposit

    NASA Technical Reports Server (NTRS)

    Espindola, J. M.; Carey, S.; Sigurdsson, H.

    1993-01-01

    The dispersal of glass spherules or tektites from a bolide impact with the Earth is modelled as ballistic trajectories in standard atmosphere. Ballistic dispersal of Cretaceous-Tertiary boundary impact glass spherules found in Haiti and Mimbral, Mexico requires a fireball radius in excess of 50 km but less than 100 km to account for the observed distribution. Glass spherules from 1 and up to 8 mm in diameter have been found at the KT boundary at Beloc in Haiti, at Mimbral, Mexico, and at DSDP Sites 536 and 540 in the Gulf of Mexico corresponding to paleodistances of 600 to 1000 km from the Chicxulub crater. In Haiti the basal and major glass-bearing unit at the KT boundary is attributed to fallout on basis of sedimentologic features. When compared with theoretical and observed dispersal of volcanic ejecta, the grain size versus distance relationship of the KT boundary tektite fallout is extreme, and rules out a volcanic fallout origin. At a comparable distance from source, the KT impact glass spherules are more than an order of mangitude coarser than ejecta of the largest known volcanic events. We model the dispersal of KT boundary impact glass spherules as ballistic ejecta from a fireball generated by the impact of a 10 km diameter bolide. Mass of ejecta in the fireball is taken as twice the bolide mass. Melt droplets are accelerated by gas flow in the fireball cloud, and leave the fireball on ballistic trajectories within the atmosphere, subject to drag, depending on angle of ejection and altitude. The model for ballistic dispersal is based on equations of motion, drag and ablation for silicate spheres in standard atmosphere.

  7. Modeling internal ballistics of gas combustion guns.

    PubMed

    Schorge, Volker; Grossjohann, Rico; Schönekess, Holger C; Herbst, Jörg; Bockholdt, Britta; Ekkernkamp, Axel; Frank, Matthias

    2016-05-01

    Potato guns are popular homemade guns which work on the principle of gas combustion. They are usually constructed for recreational rather than criminal purposes. Yet some serious injuries and fatalities due to these guns are reported. As information on the internal ballistics of homemade gas combustion-powered guns is scarce, it is the aim of this work to provide an experimental model of the internal ballistics of these devices and to investigate their basic physical parameters. A gas combustion gun was constructed with a steel tube as the main component. Gas/air mixtures of acetylene, hydrogen, and ethylene were used as propellants for discharging a 46-mm caliber test projectile. Gas pressure in the combustion chamber was captured with a piezoelectric pressure sensor. Projectile velocity was measured with a ballistic speed measurement system. The maximum gas pressure, the maximum rate of pressure rise, the time parameters of the pressure curve, and the velocity and path of the projectile through the barrel as a function of time were determined according to the pressure-time curve. The maximum gas pressure was measured to be between 1.4 bar (ethylene) and 4.5 bar (acetylene). The highest maximum rate of pressure rise was determined for hydrogen at (dp/dt)max = 607 bar/s. The muzzle energy was calculated to be between 67 J (ethylene) and 204 J (acetylene). To conclude, this work provides basic information on the internal ballistics of homemade gas combustion guns. The risk of injury to the operator or bystanders is high, because accidental explosions of the gun due to the high-pressure rise during combustion of the gas/air mixture may occur.

  8. Balancing ballistic protection against physiological strain: evidence from laboratory and field trials.

    PubMed

    Taylor, Nigel A S; Burdon, Catriona A; van den Heuvel, Anne M J; Fogarty, Alison L; Notley, Sean R; Hunt, Andrew P; Billing, Daniel C; Drain, Jace R; Silk, Aaron J; Patterson, Mark J; Peoples, Gregory E

    2016-02-01

    This project was based on the premise that decisions concerning the ballistic protection provided to defence personnel should derive from an evaluation of the balance between protection level and its impact on physiological function, mobility, and operational capability. Civilians and soldiers participated in laboratory- and field-based studies in which ensembles providing five levels of ballistic protection were evaluated, each with progressive increases in protection, mass (3.4-11.0 kg), and surface-area coverage (0.25-0.52 m(2)). Physiological trials were conducted on volunteers (N = 8) in a laboratory, under hot-dry conditions simulating an urban patrol: walking at 4 km·h(-1) (90 min) and 6 km·h(-1) (30 min or to fatigue). Field-based trials were used to evaluate tactical battlefield movements (mobility) of soldiers (N = 31) under tropical conditions, and across functional tests of power, speed, agility, endurance, and balance. Finally, trials were conducted at a jungle training centre, with soldiers (N = 32) patrolling under tropical conditions (averaging 5 h). In the laboratory, work tolerance was reduced as protection increased, with deep-body temperature climbing relentlessly. However, the protective ensembles could be grouped into two equally stressful categories, each providing a different level of ballistic protection. This outcome was supported during the mobility trials, with the greatest performance decrement evident during fire and movement simulations, as the ensemble mass was increased (-2.12%·kg(-1)). The jungle patrol trials similarly supported this outcome. Therefore, although ballistic protection does increase physiological strain, this research has provided a basis on which to determine how that strain can be balanced against the mission-specific level of required personal protection.

  9. Partitioning of pyroclasts between ballistic transport and a convective plume: Kīlauea volcano, 19 March 2008

    NASA Astrophysics Data System (ADS)

    Houghton, B. F.; Swanson, D. A.; Biass, S.; Fagents, S. A.; Orr, T. R.

    2017-05-01

    We describe the discrete ballistic and wind-advected products of a small, but exceptionally well-characterized, explosive eruption of wall-rock-derived pyroclasts from Kīlauea volcano on 19 March 2008 and, for the first time, integrate the size distribution of the two subpopulations to reconstruct the true size distribution of a population of pyroclasts as it exited from the vent. Based on thinning and fining relationships, the wind-advected fraction had a mass of 6.1 × 105 kg and a thickness half distance of 110 m, placing it at the bottom end of the magnitude and intensity spectra of pyroclastic falls. The ballistic population was mapped, in the field and by using structure-from-motion techniques, to a diameter of > 10-20 cm over an area of 0.1 km2, with an estimated mass of 1 × 105 kg. Initial ejection velocities of 50-80 m/s were estimated from inversion of isopleths. The total grain size distribution was estimated by using a mass partitioning of 98% of wind-advected material and 2% of ballistics, resulting in median and sorting values of -1.7ϕ and 3.1ϕ. It is markedly broader than those calculated for the products of magmatic explosive eruptions, because the grain size of 19 March 2008 clast population is unrelated to a volcanic fragmentation event and instead was "inherited" from a population of talus clasts that temporary blocked the vent prior to the eruption. Despite a conspicuous near-field presence, the ballistic subpopulation has only a minor influence on the grain size distribution because of its rapid thinning and fining away from source.

  10. Ballistic stretching increases flexibility and acute vertical jump height when combined with basketball activity.

    PubMed

    Woolstenhulme, Mandy T; Griffiths, Christine M; Woolstenhulme, Emily M; Parcell, Allen C

    2006-11-01

    Stretching is often included as part of a warm-up procedure for basketball activity. However, the efficacy of stretching with respect to sport performance has come into question. We determined the effects of 4 different warm-up protocols followed by 20 minutes of basketball activity on flexibility and vertical jump height. Subjects participated in 6 weeks (2 times per week) of warm-up and basketball activity. The warm-up groups participated in ballistic stretching, static stretching, sprinting, or basketball shooting (control group). We asked 3 questions. First, what effect does 6 weeks of warm-up exercise and basketball play have on both flexibility and vertical jump height? We measured sit and reach and vertical jump height before (week -1) and after (week 7) the 6 weeks. Flexibility increased for the ballistic, static, and sprint groups compared to the control group (p < 0.0001), while vertical jump height did not change for any of the groups. Our second question was what is the acute effect of each warm-up on vertical jump height? We measured vertical jump immediately after the warm-up on 4 separate occasions during the 6 weeks (at weeks 0, 2, 4, and 6). Vertical jump height was not different for any group. Finally, our third question was what is the acute effect of each warm-up on vertical jump height following 20 minutes of basketball play? We measured vertical jump height immediately following 20 minutes of basketball play at weeks 0, 2, 4, and 6. Only the ballistic stretching group demonstrated an acute increase in vertical jump 20 minutes after basketball play (p < 0.05). Coaches should consider using ballistic stretching as a warm-up for basketball play, as it is beneficial to vertical jump performance.

  11. Imaging ballistic carrier trajectories in graphene using scanning gate microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morikawa, Sei; Masubuchi, Satoru; Dou, Ziwei

    2015-12-14

    We use scanning gate microscopy to map out the trajectories of ballistic carriers in high-mobility graphene encapsulated by hexagonal boron nitride and subject to a weak magnetic field. We employ a magnetic focusing geometry to image carriers that emerge ballistically from an injector, follow a cyclotron path due to the Lorentz force from an applied magnetic field, and land on an adjacent collector probe. The local electric field generated by the scanning tip in the vicinity of the carriers deflects their trajectories, modifying the proportion of carriers focused into the collector. By measuring the voltage at the collector while scanningmore » the tip, we are able to obtain images with arcs that are consistent with the expected cyclotron motion. We also demonstrate that the tip can be used to redirect misaligned carriers back to the collector.« less

  12. BALLIST: A computer program to empirically predict the bumper thickness required to prevent perforation of the Space Station by orbital debris

    NASA Technical Reports Server (NTRS)

    Rule, William Keith

    1991-01-01

    A computer program called BALLIST that is intended to be a design tool for engineers is described. BALLlST empirically predicts the bumper thickness required to prevent perforation of the Space Station pressure wall by a projectile (such as orbital debris) as a function of the projectile's velocity. 'Ballistic' limit curves (bumper thickness vs. projectile velocity) are calculated and are displayed on the screen as well as being stored in an ASCII file. A Whipple style of spacecraft wall configuration is assumed. The predictions are based on a database of impact test results. NASA/Marshall Space Flight Center currently has the capability to generate such test results. Numerical simulation results of impact conditions that can not be tested (high velocities or large particles) can also be used for predictions.

  13. Room-Temperature Quantum Ballistic Transport in Monolithic Ultrascaled Al-Ge-Al Nanowire Heterostructures.

    PubMed

    Sistani, Masiar; Staudinger, Philipp; Greil, Johannes; Holzbauer, Martin; Detz, Hermann; Bertagnolli, Emmerich; Lugstein, Alois

    2017-08-09

    Conductance quantization at room temperature is a key requirement for the utilizing of ballistic transport for, e.g., high-performance, low-power dissipating transistors operating at the upper limit of "on"-state conductance or multivalued logic gates. So far, studying conductance quantization has been restricted to high-mobility materials at ultralow temperatures and requires sophisticated nanostructure formation techniques and precise lithography for contact formation. Utilizing a thermally induced exchange reaction between single-crystalline Ge nanowires and Al pads, we achieved monolithic Al-Ge-Al NW heterostructures with ultrasmall Ge segments contacted by self-aligned quasi one-dimensional crystalline Al leads. By integration in electrostatically modulated back-gated field-effect transistors, we demonstrate the first experimental observation of room temperature quantum ballistic transport in Ge, favorable for integration in complementary metal-oxide-semiconductor platform technology.

  14. Ballistic delivery of dyes for structural and functional studies of the nervous system

    PubMed Central

    Gan, Wen-Biao; Grutzendler, Jaime; Wong, Rachel O.; Lichtman, Jeff W.

    2010-01-01

    This chapter describes a detail protocol for rapid labeling of cells in a variety of preparations by means of particle-mediated ballistic (gene gun) delivery of fluorescent dyes. This method has been used for rapid labeling of cells with either lipid or water-soluble dyes in a variety of preparations. In particular, carbocyanine lipophilic dyes such as DiI have been used to obtain Golgi-like labeling of neurons and glia in fixed and live cell cultures, brain slices, as well as fixed post-mortem human brain. Water-soluble calcium indicators such as calcium green-1 dextran have been used to image calcium dynamics in living brain slices and retinal explants. This ballistic labeling technique is thus useful for studying the structure and function of neurons and glia in both living and fixed specimens. PMID:20147144

  15. Absorptive pinhole collimators for ballistic Dirac fermions in graphene

    PubMed Central

    Barnard, Arthur W.; Hughes, Alex; Sharpe, Aaron L.; Watanabe, Kenji; Taniguchi, Takashi; Goldhaber-Gordon, David

    2017-01-01

    Ballistic electrons in solids can have mean free paths far larger than the smallest features patterned by lithography. This has allowed development and study of solid-state electron-optical devices such as beam splitters and quantum point contacts, which have informed our understanding of electron flow and interactions. Recently, high-mobility graphene has emerged as an ideal two-dimensional semimetal that hosts unique chiral electron-optical effects due to its honeycomb crystalline lattice. However, this chiral transport prevents the simple use of electrostatic gates to define electron-optical devices in graphene. Here we present a method of creating highly collimated electron beams in graphene based on collinear pairs of slits, with absorptive sidewalls between the slits. By this method, we achieve beams with angular width 18° or narrower, and transmission matching classical ballistic predictions. PMID:28504264

  16. The proliferation of aerospace weapons technology: Ballistic missiles and the case of Brazil

    NASA Astrophysics Data System (ADS)

    Vossen, Terrence John

    1993-04-01

    The rationale behind the development of ballistic missile production in Brazil is examined by exploring the political, military, and economic determinants of ballistic missile demand in that country. To ascertain how Brazil developed missile production capabilities, the contributions of aerospace industries in industrialized states, the Brazilian space program, trade between less-developed countries, and illicit trade in missile technology are assessed. It is argued that missile development increasingly became a function of economic as opposed to security considerations, and that technologies transferred from developed country aerospace firms and Brazil's space program were primarily responsible for the creation of production capabilities. It is also contended that the proliferation of missile technology to Brazil was consistent with the workings of a system evident in the aerospace weapons technology market that sustains the horizontal spread of weapons production capabilities.

  17. Short Ballistic Josephson Coupling in Planar Graphene Junctions with Inhomogeneous Carrier Doping

    NASA Astrophysics Data System (ADS)

    Park, Jinho; Lee, Jae Hyeong; Lee, Gil-Ho; Takane, Yositake; Imura, Ken-Ichiro; Taniguchi, Takashi; Watanabe, Kenji; Lee, Hu-Jong

    2018-02-01

    We report on short ballistic (SB) Josephson coupling in junctions embedded in a planar heterostructure of graphene. Ballistic Josephson coupling is confirmed by the Fabry-Perot-type interference of the junction critical current Ic . The product of Ic and the normal-state junction resistance RN , normalized by the zero-temperature gap energy Δ0 of the superconducting electrodes, turns out to be exceptionally large close to 2, an indication of strong Josephson coupling in the SB junction limit. However, Ic shows a temperature dependence that is inconsistent with the conventional short-junction-like behavior based on the standard Kulik-Omel'yanchuk prediction. We argue that this feature stems from the effects of inhomogeneous carrier doping in graphene near the superconducting contacts, although the junction is in fact in the short-junction limit.

  18. A ballistic investigation of the aerodynamic characteristics of a blunt vehicle at hypersonic speeds in carbon dioxide and air

    NASA Technical Reports Server (NTRS)

    Packard, James D.; Griffith, Wayland C.; Yates, Leslie A.; Strawa, Anthony W.

    1992-01-01

    Missions to Mars require the successful development of aerobraking technology, and therefore a blunt cone representative of aerobrake shapes is investigated. Ballistic tests of the Pioneer Venus configuration are conducted in carbon dioxide and air at Mach numbers from 7 to 20 and Reynolds numbers from 0.1 x 10 exp 5 to 4 x 10 exp 6. Experimental results show that for defined conditions aerodynamic research can be conducted in air rather than carbon dioxide, providing savings in time and money. In addition, the results offer a prediction of flight aerodynamics during entry into the Martian atmosphere. Also discussed is a comparison of results from two data-reduction techniques showing that a five-degree-of-freedom routine employing weighted least-squares with differential corrections analyzes ballistic data more accurately.

  19. Correlation of nosetip boundary-layer transition data measured in ballistics-range experiments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reda, D.C.

    1980-01-01

    Preablated nosetips of various carbonaceous materials were tested in a ballistics range. Surface-temperature contours, measured with image-converter cameras, were used to define boundary-layer transition-front contours. Measurements of surface roughness, surface temperature, average transition-front location, and freestream environment were combined with calculations of nosetip flowfields, and with calculations of laminar boundary-layer development in these flowfields, to transform all data into various dimensionless parameters. These parameters were defined by previous attempts to correlate existing wind-tunnel data for transition on rough/blunt bodies. Of the available correlating techniques, only one, based on the concept of a constant (critical) roughness Reynolds number for transition, wasmore » found to successfully describe both the wind-tunnel and ballistics-range data, thereby validating the extrapolation of this concept to actual reentry-vehicle materials and environments.« less

  20. Depth-resolved ballistic imaging in a low-depth-of-field optical Kerr gated imaging system

    NASA Astrophysics Data System (ADS)

    Zheng, Yipeng; Tan, Wenjiang; Si, Jinhai; Ren, YuHu; Xu, Shichao; Tong, Junyi; Hou, Xun

    2016-09-01

    We demonstrate depth-resolved imaging in a ballistic imaging system, in which a heterodyned femtosecond optical Kerr gate is introduced to extract useful imaging photons for detecting an object hidden in turbid media and a compound lens is proposed to ensure both the depth-resolved imaging capability and the long working distance. Two objects of about 15-μm widths hidden in a polystyrene-sphere suspension have been successfully imaged with approximately 600-μm depth resolution. Modulation-transfer-function curves with the object in and away from the object plane have also been measured to confirm the depth-resolved imaging capability of the low-depth-of-field (low-DOF) ballistic imaging system. This imaging approach shows potential for application in research of the internal structure of highly scattering fuel spray.

  1. Current nuclear threats and possible responses

    NASA Astrophysics Data System (ADS)

    Lamb, Frederick K.

    2005-04-01

    Over the last 50 years, the United States has spent more than 100 billion developing and building a variety of systems intended to defend its territory against intercontinental-range ballistic missiles. Most of these systems never became operational and ultimately all were judged ineffective. The United States is currently spending about 10 billion per year developing technologies and systems intended to defend against missiles that might be acquired in the future by North Korea or Iran. This presentation will discuss these efforts ad whether they are likely to be more effective than those of the past. It will also discuss the proper role of anti-ballistic programs at a time when the threat of a nuclear attack on the U.S. by terrorists armed with nuclear weapons is thought to be much higher than the threat of an attack by nuclear-armed ballistic missles.

  2. Compressed exponential relaxation in liquid silicon: Universal feature of the crossover from ballistic to diffusive behavior in single-particle dynamics

    NASA Astrophysics Data System (ADS)

    Morishita, Tetsuya

    2012-07-01

    We report a first-principles molecular-dynamics study of the relaxation dynamics in liquid silicon (l-Si) over a wide temperature range (1000-2200 K). We find that the intermediate scattering function for l-Si exhibits a compressed exponential decay above 1200 K including the supercooled regime, which is in stark contrast to that for normal "dense" liquids which typically show stretched exponential decay in the supercooled regime. The coexistence of particles having ballistic-like motion and those having diffusive-like motion is demonstrated, which accounts for the compressed exponential decay in l-Si. An attempt to elucidate the crossover from the ballistic to the diffusive regime in the "time-dependent" diffusion coefficient is made and the temperature-independent universal feature of the crossover is disclosed.

  3. A numerical study of the nanoribbon field-effect transistors under the ballistic and dissipative transport

    NASA Astrophysics Data System (ADS)

    Ghoreishi, Seyed Saleh; Yousefi, Reza; Saghafi, Kamyar; Aderang, Habib

    2017-08-01

    In this article, a detailed performance comparison is made between ballistic and dissipative quantum transport of metal oxide semicondutor-like graphene nanoribbon field-effect transistor, in ON and OFF-state conditions. By the self-consistent mode-space non-equilibrium Green's function approach, inter- and intraband scattering is accounted and the role of acoustic and optical phonon scattering on the performance of the devices is evaluated. We found that in this structure the dominant mechanism of scattering changes according to the ranges of voltage bias. Under large biasing conditions, the influence of optical phonon scattering becomes important. Also, the ambipolar and OFF-current are impressed by the phonon-assisted band-to-band tunneling and increased considerably compared to the ballistic conditions, although sub-threshold swing degrades due to optical phonon scattering.

  4. Depth-resolved ballistic imaging in a low-depth-of-field optical Kerr gated imaging system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zheng, Yipeng; Tan, Wenjiang, E-mail: tanwenjiang@mail.xjtu.edu.cn; Si, Jinhai

    2016-09-07

    We demonstrate depth-resolved imaging in a ballistic imaging system, in which a heterodyned femtosecond optical Kerr gate is introduced to extract useful imaging photons for detecting an object hidden in turbid media and a compound lens is proposed to ensure both the depth-resolved imaging capability and the long working distance. Two objects of about 15-μm widths hidden in a polystyrene-sphere suspension have been successfully imaged with approximately 600-μm depth resolution. Modulation-transfer-function curves with the object in and away from the object plane have also been measured to confirm the depth-resolved imaging capability of the low-depth-of-field (low-DOF) ballistic imaging system. Thismore » imaging approach shows potential for application in research of the internal structure of highly scattering fuel spray.« less

  5. Randomization Procedures Applied to Analysis of Ballistic Data

    DTIC Science & Technology

    1991-06-01

    test,;;15. NUMBER OF PAGES data analysis; computationally intensive statistics ; randomization tests; permutation tests; 16 nonparametric statistics ...be 0.13. 8 Any reasonable statistical procedure would fail to support the notion of improvement of dynamic over standard indexing based on this data ...AD-A238 389 TECHNICAL REPORT BRL-TR-3245 iBRL RANDOMIZATION PROCEDURES APPLIED TO ANALYSIS OF BALLISTIC DATA MALCOLM S. TAYLOR BARRY A. BODT - JUNE

  6. 2005 22nd International Symposium on Ballistics Volume 2 Wednesday

    DTIC Science & Technology

    2005-11-18

    Information 1 Experimental and Numerical Study of the Penetration of Tungsten Carbide Into Steel Targets During High Rates of Strain John F . Moxnes...QinetiQ; Vladimir Titarev, Eleuterio Toro , Umeritek Limited The Mechanism Analysis of Interior Ballistics of Serial Chamber Gun, Dr. Sanjiu Ying, Charge...Elements and Meshless Particles, Gordon R. Johnson and Robert A. Stryk, Network Computing Services, Inc. Experimental and Numerical Study of the

  7. Military Power of the People’s Republic of China

    DTIC Science & Technology

    2009-01-01

    executed for taking bribes to approve fake drugs. Environment . China’s economic development has come at a significant environmental cost. Acceptable air... ASEAN : Association of Southeast Asian Nations ASEM: Asia-Europe Meeting ASBM: Anti-Ship Ballistic Missile ASCM: Anti-Ship Cruise Missile ASM: Air-to...Capability IRBM: Intermediate-Range Ballistic Missile LACM: Land Attack Cruise Missile LEO: Low Earth Orbit MaRV: Maneuvering Re- entry Vehicle MINUSTAH

  8. Navy Aegis Ballistic Missile Defense (BMD) Program: Background and Issues for Congress

    DTIC Science & Technology

    2013-10-17

    and Gettysburg (CG-64), Chosin (CG-65), and Hue City (CG-66), which were proposed for retirement in FY2014. These ships entered service between 1991...continued) IOT &E With A Bang, Full-Rate Production Review,” Inside the Navy, October 7, 2013. 85...upgraded and rearchitectured SMART -L D-band volume search radar that will give the ships a ballistic missile defence (BMD) early warning capability

  9. Measuring the Blast and Ballistic Performance of Armor

    DTIC Science & Technology

    2015-10-15

    Typical ballistic test instrumentation is depicted in Fig. 1. The gun system employs a Mann barrel , available in a range of calibers1 (e.g., .22 cal...setup. (A) Mann barrel gun system; (B) computer and data acquisition interface; (C) remote, manual trigger; (D) velocity screens; (E) high speed video...1 Caliber corresponds to the diameter of the gun barrel , usually expressed in inches; e.g., .30 cal

  10. Quantum logic gates based on ballistic transport in graphene

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dragoman, Daniela; Academy of Romanian Scientists, Splaiul Independentei 54, 050094 Bucharest; Dragoman, Mircea, E-mail: mircea.dragoman@imt.ro

    2016-03-07

    The paper presents various configurations for the implementation of graphene-based Hadamard, C-phase, controlled-NOT, and Toffoli gates working at room temperature. These logic gates, essential for any quantum computing algorithm, involve ballistic graphene devices for qubit generation and processing and can be fabricated using existing nanolithographical techniques. All quantum gate configurations are based on the very large mean-free-paths of carriers in graphene at room temperature.

  11. Ballistic Testing of Australian Bisalloy Steel for Armor Applications

    DTIC Science & Technology

    2007-06-01

    CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON Dwight D. Showalter a . REPORT UNCLASSIFIED b. ABSTRACT UNCLASSIFIED c . THIS PAGE UNCLASSIFIED 17...WASHINGTON PA 15301 A ND 2 SOUTHWEST RSCH INST C ANDERSON J WALKER 6220 CULEB SAN ANTONIO TX 7 DEPT OF APPL MECH & SVC R011 S NEMAT...Ballistic Testing of Australian Bisalloy Steel for Armor Applications by Dwight D. Showalter, William A . Gooch, Matt S. Burkins, Victoria

  12. Charge Design Considerations and Their Effect on Pressure Waves in Guns

    DTIC Science & Technology

    1980-12-01

    Interior Ballistic Analysis of Guns", "Interior Ballistics of Guns Ed, M. Summerfield and H. Krier, Progress in Astro - nautics and Aeronautics, Vol. 66...8217 • - -O.8 - Fx " • 0.48 S0.2 U G 00 2 4 64_ . -APi (kpsi) Figure 28. Distribution of Pressure-Wave Amplitudes f r the 175-mm, M107 Gun (M86A2, Zone 3

  13. USSR Report, Military Affairs Foreign Military Review No 6, June 1986

    DTIC Science & Technology

    1986-11-20

    computers used for an objective accounting of the difference in current firing conditions from standard hold an important place in integrated fire...control systems of modern tanks of capitalist countries. Mechanical ballistic computers gave way in the early 1970’s to electronic computers , initially...made with analog components. Then digital ballistic computers were created, installed in particular in the Ml Abrams and Leopard-2 tanks. The basic

  14. Tolerance of the skull to blunt ballistic temporo-parietal impact.

    PubMed

    Raymond, David; Van Ee, Chris; Crawford, Gregory; Bir, Cynthia

    2009-11-13

    Less-lethal ballistic projectiles are used by police personnel to temporarily incapacitate suspects. While the frequency of these impacts to the head is low, they account for more serious injuries than impacts to any other body region. As a result, there is an urgent need to assess the tolerance of the head to such impacts. The focus of this study was to investigate the tolerance of the temporo-parietal skull to blunt ballistic impact and establish injury criteria for risk assessment. Seven unembalmed isolated cadaver heads were subjected to fourteen impacts. Specimens were instrumented with a nine-accelerometer array as well as strain gages surrounding the impact site. Impacts were performed with a 38 mm instrumented projectile at velocities ranging from 18 to 37 m/s. CT images and autopsies were performed to document resulting fractures. Peak fracture force for the seven resulting fractures was 5633+/-2095 N. Peak deformation for fracture-producing impacts was 7.8+/-3.2 mm. The blunt criterion (BC), peak force and principal strain were determined to be the best predictors of depressed comminuted fractures. Temporo-parietal tolerance levels were consistent with previous studies. An initial force tolerance level of 2346 N is established for the temporo-parietal region for blunt ballistic impact with a 38 mm diameter impactor.

  15. Is muscle coordination affected by loading condition in ballistic movements?

    PubMed

    Giroux, Caroline; Guilhem, Gaël; Couturier, Antoine; Chollet, Didier; Rabita, Giuseppe

    2015-02-01

    This study aimed to investigate the effect of loading on lower limb muscle coordination involved during ballistic squat jumps. Twenty athletes performed ballistic squat jumps on a force platform. Vertical force, velocity, power and electromyographic (EMG) activity of lower limb muscles were recorded during the push-off phase and compared between seven loading conditions (0-60% of the concentric-only maximal repetition). The increase in external load increased vertical force (from 1962 N to 2559 N; P=0.0001), while movement velocity decreased (from 2.5 to 1.6 ms(-1); P=0.0001). EMG activity of tibialis anterior first peaked at 5% of the push-off phase, followed by gluteus maximus (35%), vastus lateralis and soleus (45%), rectus femoris (55%), gastrocnemius lateralis (65%) and semitendinosus (75%). This sequence of activation (P=0.67) and the amplitude of muscle activity (P=0.41) of each muscle were not affected by loading condition. However, a main effect of muscle was observed on these parameters (peak value: P<0.001; peak occurrence: P=0.02) illustrating the specific role of each muscle during the push-off phase. Our findings suggest that muscle coordination is not influenced by external load during a ballistic squat jump. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Comparison of impact results for several polymeric composites over a wide range of low impact velocities

    NASA Technical Reports Server (NTRS)

    Poe, C. C., Jr.; Portanova, M. A.; Masters, J. E.; Sankar, B. V.; Jackson, Wade C.

    1991-01-01

    Static indentation, falling weight, and ballistic impact tests were conducted in clamped plates made of AS4/3501-6 and IM7/8551-7 prepreg tape. The transversely isotropic plates were nominally 7-mm thick. Pendulum and ballistic tests were also conducted on simply supported plates braided with Celion 12000 fibers and 3501-6 epoxy. The 20 degree braided plates were about 5-mm thick. The impactors had spherical or hemispherical shapes with a 12.7 mm diameter. Residual compression strength and damage size were measured. For a given kinetic energy, damage size was least for IM7/8551-7 and greatest for the braided material. Strengths varied inversely with damage size. For a given damage size, strength loss as a fraction of original strength was least for the braided material and greatest for AS4/3501-6 and IM7/8551-7. Strength loss for IM7/8551-7 and AS4/3501-6 was nearly equal. No significant differences were noticed between damage sizes and residual compression strengths for the static indentation, falling weight, and ballistic tests of AS4/3501-6 and IM7/8551-7. For the braided material, sizes of damage were significantly less and compression strengths were significantly more for the falling weight tests than for the ballistic tests.

  17. Viscoelastic shock wave in ballistic gelatin behind soft body armor.

    PubMed

    Liu, Li; Fan, Yurun; Li, Wei

    2014-06-01

    Ballistic gelatins are widely used as a surrogate of biological tissue in blunt trauma tests. Non-penetration impact tests of handgun bullets on the 10wt% ballistic gelatin block behind soft armor were carried out in which a high-speed camera recorded the crater׳s movement and pressure sensors imbedded in the gelatin block recorded the pressure waves at different locations. The observed shock wave attenuation indicates the necessity of considering the gelatin׳s viscoelasticity. A three-element viscoelastic constitutive model was adopted, in which the relevant parameters were obtained via fitting the damping free oscillations at the beginning of the creep-mode of rheological measurement, and by examining the data of published split Hopkinson pressure bar (SHPB) experiments. The viscoelastic model is determined by a retardation time of 5.5×10(-5)s for high oscillation frequencies and a stress relaxation time of 2.0-4.5×10(-7)s for shock wave attenuation. Using the characteristic-line method and the spherical wave assumption, the propagation of impact pressure wave front and the subsequent unloading profile can be simulated using the experimental velocity boundary condition. The established viscoelastic model considerably improves the prediction of shock wave attenuation in the ballistic gelatin. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Ballistic Phonon Penetration Depth in Amorphous Silicon Dioxide.

    PubMed

    Yang, Lin; Zhang, Qian; Cui, Zhiguang; Gerboth, Matthew; Zhao, Yang; Xu, Terry T; Walker, D Greg; Li, Deyu

    2017-12-13

    Thermal transport in amorphous silicon dioxide (a-SiO 2 ) is traditionally treated as random walks of vibrations owing to its greatly disordered structure, which results in a mean free path (MFP) approximately the same as the interatomic distance. However, this picture has been debated constantly and in view of the ubiquitous existence of thin a-SiO 2 layers in nanoelectronic devices, it is imperative to better understand this issue for precise thermal management of electronic devices. Different from the commonly used cross-plane measurement approaches, here we report on a study that explores the in-plane thermal conductivity of double silicon nanoribbons with a layer of a-SiO 2 sandwiched in-between. Through comparing the thermal conductivity of the double ribbon samples with that of corresponding single ribbons, we show that thermal phonons can ballistically penetrate through a-SiO 2 of up to 5 nm thick even at room temperature. Comprehensive examination of double ribbon samples with various oxide layer thicknesses and van der Waals bonding strengths allows for extraction of the average ballistic phonon penetration depth in a-SiO 2 . With solid experimental data demonstrating ballistic phonon transport through a-SiO 2 , this work should provide important insight into thermal management of electronic devices.

  19. Development of a skull/brain model for military wound ballistics studies.

    PubMed

    Carr, Debra; Lindstrom, Anne-Christine; Jareborg, Andreas; Champion, Stephen; Waddell, Neil; Miller, David; Teagle, Michael; Horsfall, Ian; Kieser, Jules

    2015-05-01

    Reports on penetrating ballistic head injuries in the literature are dominated by case studies of suicides; the penetrating ammunition usually being .22 rimfire or shotgun. The dominating cause of injuries in modern warfare is fragmentation and hence, this is the primary threat that military helmets protect the brain from. When helmets are perforated, this is usually by bullets. In combat, 20% of penetrating injuries occur to the head and its wounding accounts for 50% of combat deaths. A number of head simulants are described in the academic literature, in ballistic test methods for helmets (including measurement of behind helmet blunt trauma, BHBT) and in the 'open' and 'closed' government literature of several nations. The majority of these models are not anatomically correct and are not assessed with high-velocity rifle ammunition. In this article, an anatomically correct 'skull' (manufactured from polyurethane) and 'brain' (manufactured from 10%, by mass, gelatine) model for use in military wound ballistic studies is described. Filling the cranium completely with gelatine resulted in a similar 'skull' fracture pattern as an anatomically correct 'brain' combined with a representation of cerebrospinal fluid. In particular, posterior cranial fossa and occipital fractures and brain ejection were observed. This pattern of injury compared favourably to reported case studies of actual incidents in the literature.

  20. Terminal ballistics of the 9mm with Action Safety bullet or Blitz-Action-Trauma (BAT) ammunition.

    PubMed

    Lantz, P E; Stone, R S; Broudy, D; Morgan, T M

    1994-05-01

    Specialty ammunition creating atypical gunshot wounds of entrance can create confusion and may be misinterpreted by pathologists unfamiliar with the terminal ballistics of these projectiles. The previously unreported wound ballistics caused by the 9mm with Action Safety bullet described in a homicide highlights the atypical entrance wound(s) and wounding capacity of this novel ammunition. Manufactured by Geco division of Dynamit Nobel, the bullet consists of a nonjacketed solid copper alloy bullet body without a conventional lead core. The large deformation well and part of the smaller central channel is filled with a hard plastic core and post that creates a round nose bullet. The internal ballistics and unique design allow the plastic nose cap and post to separate from the copper alloy base while still in the barrel. The radiolucent nose cap leaves the bullet's path but can still penetrate tissue giving the appearance of a separate but smaller entrance wound. The sharp leading edge of the deformation well and relative high velocity of the bullet body creates a punched out entrance wound with minimal marginal abrasion. When the plastic nose cap or fragments of the plastic post impact the subject, test firings may allow an inference to the muzzle-target distance even in the absence of soot deposition or stippling.

  1. Estimates of point defect production in α-quartz using molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Cowen, Benjamin J.; El-Genk, Mohamed S.

    2017-07-01

    Molecular dynamics (MD) simulations are performed to investigate the production of point defects in α-quartz by oxygen and silicon primary knock-on atoms (PKAs) of 0.25-2 keV. The Wigner-Seitz (WS) defect analysis is used to identify the produced vacancies, interstitials, and antisites, and the coordination defect analysis is used to identify the under and over-coordinated oxygen and silicon atoms. The defects at the end of the ballistic phase and the residual defects, after annealing, increase with increased PKA energy, and are statistically the same for the oxygen and silicon PKAs. The WS defect analysis results show that the numbers of the oxygen vacancies and interstitials (VO, Oi) at the end of the ballistic phase is the highest, followed closely by those of the silicon vacancies and interstitials (VSi, Sii). The number of the residual oxygen and silicon vacancies and interstitials are statistically the same. In addition, the under-coordinated OI and SiIII, which are the primary defects during the ballistic phase, have high annealing efficiencies (>89%). The over-coordinated defects of OIII and SiV, which are not nearly as abundant in the ballistic phase, have much lower annealing efficiencies (<63%) that decrease with increased PKA energy.

  2. Atmospheric Entry Studies for Venus Missions: 45 Sphere-Cone Rigid Aeroshells and Ballistic Entries

    NASA Technical Reports Server (NTRS)

    Prabhu, Dinesh K.; Spilker, Thomas R.; Allen, Gary A., Jr.; Hwang, Helen H.; Cappuccio, Gelsomina; Moses, Robert W.

    2013-01-01

    The present study considers direct ballistic entries into the atmosphere of Venus using a 45deg sphere-cone rigid aeroshell, a legacy shape that has been used successfully in the past in the Pioneer Venus Multiprobe Mission. For a number of entry mass and heatshield diameter combinations (i.e., various ballistic coefficients) and entry velocities, the trajectory space in terms of entry flight path angles between skip out and -30deg is explored with a 3DoF trajectory code, TRAJ. From these trajectories, the viable entry flight path angle space is determined through the use of mechanical and thermal performance limits on the thermal protection material and science payload; the thermal protection material of choice is entry-grade carbon phenolic, for which a material thermal response model is available. For mechanical performance, a 200 g limit is placed on the peak deceleration load experienced by the science instruments, and 10 bar is assumed as the pressure limit for entry-grade carbon-phenolic material. For thermal performance, inflection points in the total heat load distribution are used as cut off criteria. Analysis of the results shows the existence of a range of critical ballistic coefficients beyond which the steepest possible entries are determined by the pressure limit of the material rather than the deceleration load limit.

  3. Dynamics of correlations in long-range quantum systems follwing a quantum quench

    NASA Astrophysics Data System (ADS)

    Cevolani, Lorenzo; Carleo, Giuseppe; Sanchez-Palencia, Laurent

    We study how and how fast correlations can spread in a quantum system abruptly driven out of equilibrium by a quantum quench. This protocol can be experimentally realized and it allow to address fundamental questions concerning the quasi-locality principle in isolated quantum systems with both short- and long-range interactions. We focus on two different models describing, respectively, lattice bosons, and spins. Our study is based on a combined approach, based on one hand on accurate many-body numerical calculations and on the other hand on a quasi-particle microscopic theory. We find that, for sufficiently fast decaying interaction potential the propagation is ballistic and the Lieb-Robinson bounds for long-range interactions are never attained. When the interactions are really long-range, the scenario is completely different in the two cases. In the bosonic system the locality is preserved and a ballistic propagation is still present while in the spin system an instantaneous propagation of correlations completely destroys locality. Using the microscopic point of view we can quantitatively describe all the different regimes, from instantaneous to ballistic, found in the spin model and we explain how locality is protected in the bosonic model leading to a ballistic propagation. ERC (FP7/2007-2013 No. 256294), QUIC (H2020 No. 641122).

  4. Ballistic Testing and Product Quality Surveillance for the Interceptor Body Armor - Vest Components Need Improvement

    DTIC Science & Technology

    2011-01-03

    six contracts. Interceptor Body Armor – Vest Components IBA is a modular body armor system that consists of an OTV, ceramic plates , and components...Armor - Vest Components Need Improvement Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the...Ballistic Testing and Product Quality Surveillance for the Interceptor Body Armor - Vest Components Need Improvement 5a. CONTRACT NUMBER 5b. GRANT

  5. The Effects of Propellant Burn on the Surface Composition of Gun Steel

    DTIC Science & Technology

    1981-11-01

    ion beam analysis method has been used to characterize the depths and compositions of the outer, sub-micron layers of gun steel surfaces that have...STEEL A. Niiler R. Birkmire S. E. Caldwell November 1981 US ARMY ARMAMENT RESEARCH AND DEVELOPMENT COMMAND BALLISTIC RESEARCH LABORATORY...1L162618AH80 11. CONTROLLING OFFICE NAME AND ADDRESS US Army Armament Research § Development Command Ballistic Research Laboratory ATTN: DRDAR-BL. APG

  6. Evaluation of a Belt-Cast Austenitic Steel Alloy from Salzgitter Mannesmann Forschung: Effect of Hardness on the Ballistic Resistance against Two 0.30-cal. Projectile Types

    DTIC Science & Technology

    2017-08-01

    obtained from Salzgitter Mannesmann Forschung, a German steel manufacturing concern. The steel samples were subjected to microstructural and quasi ... Experimental Procedures 4 4. Results and Discussion 7 4.1 Microstructural and Mechanical Properties 7 4.2 Ballistic Testing 14 5. Summary and Conclusions...austenitic steels. Reprinted with permission. ................................................................... 2 Fig. 2 Experimental setup. A

  7. International Infantry and Joint Services Small Arms Systems Symposium: Exhibition and Firing Demonstration

    DTIC Science & Technology

    2008-05-22

    operation of weapon system) Phit Weapon System (e.g. dispersion) Most important influence ● Operator ● Distance to target together with ballistic...Suitable for a variety of weapons where ballistical correction to improve range performance and PHit /PKill is essential ● Prepare system for additional...status ● Prototypes have been delivered to FMV (Swedish Defence Materiel Administration) ● Demonstrated for NATO in Toledo 2007-02-15: > 65% PHit

  8. A Method of Evaluating Laplace Transforms with Series of Complete or Incomplete Beta Functions,

    DTIC Science & Technology

    1982-12-01

    DEVELOPMENT COMMAND BALLISTIC RESEARCH LABORATORY ABERDEEN PROVING GROUND , MARYLAND A i ’:-Approved for public rlease; distribution unlimited. c...BLI Aberden Provin Ground 100161102.143 I. CONTROLLING OFFICE NAME AND ADDRESS Q?. REPORT DATE US Army Armament Research & Development Command...December 1982 US Arm), Ballistic Research Laboratory (DRDAR-BL 13. ’NUMBER OF PAGES Aberdeen Proving Ground , NMD 21005 33 14 MC5NiTORING AGENCY NAME

  9. Human Factors Engineering Program for Intercontinental Ballistic Missile Systems, (MIL-STD-1794(USAF))

    DTIC Science & Technology

    1986-10-01

    opeational test and evaluation (OT&R). The OT&B Is comprised of Initial operational test and evaluation ( IOT &R) and follow-on test and evaluation (FOT&R). OT&I...BP HYL FVAC beating, ventilation and air conditioning am. ICBM Intercntinental ballistic missile an. IOT &R Initial operational test and *valuation so...and maintenance vehicles (stop- B pod, engine idle-exterior), facility equipment utility rooms, heating, ventilation and air conditioning ( HVAC

  10. Navy Columbia Class (Ohio Replacement) Ballistic Missile Submarine (SSBN[X]) Program: Background and Issues for Congress

    DTIC Science & Technology

    2016-08-18

    of UK design and manufacture . 12 For more on the arrangement for jointly building Virginia- class boats, see CRS Report RL32418, Navy Virginia (SSN...schedule reduction in Missile Tube Module manufacturing for the OR Class . This schedule reduction, on a potential critical path assembly, would reduce...Navy Columbia Class (Ohio Replacement) Ballistic Missile Submarine (SSBN[X]) Program: Background and Issues for Congress Ronald O’Rourke

  11. Land Based Anti-Ship Missiles: A Complementary Capability for Maintaining Access in an Anti-Access/Area Denial Environment

    DTIC Science & Technology

    2014-12-01

    while underway. From S. Chandrashekar, N. Genesh, C.R. Raghunath , Rajaram Nagappa, N. Ramani and Lalitha Sundaresan, China’s Anti-Ship Ballistic...Chandrashekar, Genesh, Raghunath , Nagappa, Ramani and Sundaresan, China’s Anti- Ship Ballistic Missile Game Changer in the Pacific Ocean. International Strategic...Complete, ebscohost (accessed august 15, 2014). Chandrashekar, S., N. Genesh, C.R. Raghunath , Rajaram Nagappa, N. Ramani, and Lalitha Sundaresan

  12. Auditory Localization Performance with Gamma Integrated Eye and Ear Protection

    DTIC Science & Technology

    2016-12-01

    is unlimited. v List of Figures Fig. 1 IEEP device under test: shown with clear ballistic lens and Comply foam earphone tips...conducted with the system active. Fig. 1 IEEP device under test: shown with clear ballistic lens and Comply foam earphone tips. 1.2 Auditory...controlled acoustic facilities with large loudspeaker arrays. Method 1 has 2 listener orientations (0° and 45°) and specifies the use of 8

  13. System Requirements Analysis and Technological Support for the Ballistic Missile Defense System (BMDS) - FY07 Progress Report

    DTIC Science & Technology

    2007-07-01

    Systems , Boeing-led Airborne Laser Team Actively Tracks Airborne Target, Compensates for Atmospheric Turbulence and Fires Sur- rogate High-Energy Laser...7100 System Requirements Analysis and Technological Support for the Ballistic Missile Defense System (BMDS) FY07 Progress Report By...Office of Management and Budget , Paperwork Reduction Project (0704-0188) Washington DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE July

  14. Ballistic and snake photon imaging for locating optical endomicroscopy fibres

    PubMed Central

    Tanner, M. G.; Choudhary, T. R.; Craven, T. H.; Mills, B.; Bradley, M.; Henderson, R. K.; Dhaliwal, K.; Thomson, R. R.

    2017-01-01

    We demonstrate determination of the location of the distal-end of a fibre-optic device deep in tissue through the imaging of ballistic and snake photons using a time resolved single-photon detector array. The fibre was imaged with centimetre resolution, within clinically relevant settings and models. This technique can overcome the limitations imposed by tissue scattering in optically determining the in vivo location of fibre-optic medical instruments. PMID:28966848

  15. Defense Science Board Task Force on Defense Strategies for Advanced Ballistic and Cruise Missile Threats

    DTIC Science & Technology

    2017-01-01

    annual investment of about $2.5 billion. The study also recommended that the Department of Defense enhance its ab ility to perform the kinds of broad...homeland fundamentally change the nature of the problem to one of strategic deterrence and that the spirit of the terms of reference was more...adversary investments in regional, precision attack cruise and ballistic threaten that foundation, investments that have dramatically increased both

  16. Ballistics Modeling for Non-Axisymmetric Hypervelocity Smart Bullets

    DTIC Science & Technology

    2014-06-03

    can in principle come from experiments or computational fluid dynamics ( CFD ) calculations. CFD calculations are carried out for a standard bullet...come from experiments or com- putational fluid dynamics ( CFD ) calculations. CFD calculations are carried out for a standard bullet (0.308” 168 grain...11 2. Spin and Pitch Damping 11 3. Magnus Moment 12 IV. CFD Simulations and Ballistic Trajectories 12 A. CFD Modeling of a Standard Bullet 12 B

  17. An Extensive X-ray Computed Tomography Evaluation of a Fully Penetrated Encapsulated SiC MMC Ballistic Panel

    DTIC Science & Technology

    2009-04-01

    An Extensive X-ray Computed Tomography Evaluation of a Fully Penetrated Encapsulated SiC MMC Ballistic Panel by William H. Green and Robert H...Panel William H. Green and Robert H. Carter Weapons and Materials Research Directorate, ARL...PROGRAM ELEMENT NUMBER 2182040 6. AUTHOR(S) William H. Green and Robert H. Carter 5d. PROJECT NUMBER AH80 5e. TASK NUMBER 5f. WORK UNIT

  18. DESIGN NOTE: A modified Nanosurf scanning tunnelling microscope for ballistic electron emission microscopy and spectroscopy

    NASA Astrophysics Data System (ADS)

    Appelbaum, Ian; Thompson, Pete; van Schendel, P. J. A.

    2006-04-01

    We describe the design and implementation of modifications to an ambient STM with a slip stick approach mechanism to create a system capable of ballistic electron emission microscopy (BEEM) and spectroscopy (BEES). These modifications require building a custom sample holder which operates as a high gain transimpedance preamplifier. Results of microscopy and spectroscopy using a Au/n-GaAs Schottky device demonstrate the effectiveness of our design.

  19. Regional Power Ballistic Missiles. An Emerging Threat to Deployed US forces?

    DTIC Science & Technology

    1990-05-01

    packaging and dispensing submunitions are straightforward: the MLRS submunitions are simply nestled in polyurethane foam ; and cluster munitions such as the...several U.S. mobile ballistic missile systems, both ground-launched and air-launched. The Army Tactical Missile System ( ATACMS ), a mobile TBM...weight class have also been presented. (99:185-187) Warheads with "light" submunitions are used on the US LANCE and Army Tactical Missile System ( ATACMS

  20. Compact modeling of nanoscale triple-gate junctionless transistors covering drift-diffusion to quasi-ballistic carrier transport

    NASA Astrophysics Data System (ADS)

    Oproglidis, T. A.; Karatsori, T. A.; Barraud, S.; Ghibaudo, G.; Dimitriadis, C. A.

    2018-04-01

    In this work, we extend our analytical compact model for nanoscale junctionless triple-gate (JL TG) MOSFETs, capturing carrier transport from drift-diffusion to quasi-ballistic regime. This is based on a simple formulation of the low-field mobility extracted from experimental data using the Y-function method, taking into account the ballistic carrier motion and an increased carrier scattering in process-induced defects near the source/drain regions. The case of a Schottky junction in non-ideal ohmic contact at the drain side was also taken into account by modifying the threshold voltage and ideality factor of the JL transistor. The model is validated with experimental data for n-channel JL TG MOSFETs with channel length varying from 95 down to 25 nm. It can be easily implemented as a compact model for use in Spice circuit simulators.

  1. Reviews Toy: Air swimmers Book: Their Arrows will Darken the Sun: The Evolution and Science of Ballistics Book: Physics Experiments for your Bag Book: Quantum Physics for Poets Equipment: SEP colour wheel kit Equipment: SEP colour mixing kit Software: USB DrDAQ App: iHandy Level Equipment: Photonics Explorer kit Web Watch

    NASA Astrophysics Data System (ADS)

    2012-01-01

    WE RECOMMEND Air swimmers Helium balloon swims like a fish Their Arrows will Darken the Sun: The Evolution and Science of Ballistics Ballistics book hits the spot Physics Experiments for your Bag Handy experiments for your lessons Quantum Physics for Poets Book shows the economic importance of physics SEP colour wheel kit Wheels investigate colour theory SEP colour mixing kit Cheap colour mixing kit uses red, green and blue LEDs iHandy Level iPhone app superbly measures angles Photonics Explorer kit Free optics kit given to schools WORTH A LOOK DrDAQ DrDAQ software gets an upgrade WEB WATCH Websites show range of physics

  2. Ballistic performance of a Kevlar-29 woven fibre composite under varied temperatures

    NASA Astrophysics Data System (ADS)

    Soykasap, O.; Colakoglu, M.

    2010-05-01

    Armours are usually manufactured from polymer matrix composites and used for both military and non-military purposes in different seasons, climates, and regions. The mechanical properties of the composites depend on temperature, which also affects their ballistic characteristics. The armour is used to absorb the kinetic energy of a projectile without any major injury to a person. Therefore, besides a high strength and lightness, a high damping capacity is required to absorb the impact energy transferred by the projectile. The ballistic properties of a Kevlar 29/polyvinyl butyral composite are investigated under varied temperatures in this study. The elastic modulus of the composite is determined from the natural frequency of composite specimens at different temperatures by using a damping monitoring method. Then, the backside deformation of composite plates is analysed experimentally and numerically employing the finite-element program Abaqus. The experimental and numeric results obtained are in good agreement.

  3. Physics, ballistics, and psychology: a history of the chronoscope in/as context, 1845-1890.

    PubMed

    Schmidgen, Henning

    2005-02-01

    In Wilhelm Wundt's (1832-1920) Leipzig laboratory and at numerous other research sites, the chronoscope was used to conduct reaction time experiments. The author argues that the history of the chronoscope is the history not of an instrument but of an experimental setup. This setup was initially devised by the English physicist and instrument maker Charles Wheatstone (1802-1875) in the early 1840s. Shortly thereafter, it was improved by the German clockmaker and mechanic Matthäus Hipp (1813-1893). In the 1850s, the chronoscope was introduced to ballistic research. In the early 1860s, Neuchâtel astronomer Adolphe Hirsch (1830-1901) applied it to the problem of physiological time. The extensions and variations of chronoscope use within the contexts of ballistics, physiology, and psychology presented special challenges. These challenges were met with specific attempts to reduce the errors in chronoscopic experiments on shooting stands and in the psychological laboratory.

  4. Possible influences on bullet trajectory deflection in ballistic gelatine.

    PubMed

    Riva, Fabiano; Kerkhoff, Wim; Bolck, Annabel; Mattijssen, Erwin J A T

    2017-02-01

    The influence of the distance to the top and bottom of a gelatine block and to bullet tracks from previously fired shots on a bullet's trajectory, when passing through ballistic gelatine, was studied. No significant difference in deflection was found when trajectories of 9mm Luger bullets, fired at a 3.5cm distance to the top and bottom of a gelatine block and to bullet tracks from previously fired shots, were compared to trajectories of bullets fired 7cm or more away from any of the aforementioned aspects. A surprisingly consistent 6.5° absolute deflection angle was found when these bullets passed through 22.5 to 23.5cm of ballistic gelatine. The projection angle, determined by the direction of the deflection, appeared to be random. The consistent absolute angle, in combination with the random projection angle, resulted in a cone-like deflection pattern. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  5. Study on Ballistic Absorbing Energy Character of High Performance Polyethylene Needle Felt

    NASA Astrophysics Data System (ADS)

    Kailiang, Zhu; Jianqiao, Fu

    2017-11-01

    The ballistic performance of polyethylene needle felt is tested and the failure morphology after test is also observed. The results showed that when the non-dimensionally non-stressed fibers in polyethylene needles are subjected to high-speed projectile, secondary movement such as stretching and twisting occurs first. This secondary movement is very full, it is the main way of ballistic absorbing energy of the polyethylene needle felt which can avoid the polyethylene fiber short-term rapid heating-up and destroyed. Analysis results show that under normal temperature and humidity conditions, the V50 of 6-layer forded polyethylene needle felt sample is 250m/s. At (450 ± 50) m/s speed range of the target missile, the mean value of the penetrative specific energy absorption for 3-layer forded polyethylene needle felt anti-1.1g simulated projectiles (tapered column) reaches 24.1J·m2/kg.

  6. Ballistic superconductivity in semiconductor nanowires.

    PubMed

    Zhang, Hao; Gül, Önder; Conesa-Boj, Sonia; Nowak, Michał P; Wimmer, Michael; Zuo, Kun; Mourik, Vincent; de Vries, Folkert K; van Veen, Jasper; de Moor, Michiel W A; Bommer, Jouri D S; van Woerkom, David J; Car, Diana; Plissard, Sébastien R; Bakkers, Erik P A M; Quintero-Pérez, Marina; Cassidy, Maja C; Koelling, Sebastian; Goswami, Srijit; Watanabe, Kenji; Taniguchi, Takashi; Kouwenhoven, Leo P

    2017-07-06

    Semiconductor nanowires have opened new research avenues in quantum transport owing to their confined geometry and electrostatic tunability. They have offered an exceptional testbed for superconductivity, leading to the realization of hybrid systems combining the macroscopic quantum properties of superconductors with the possibility to control charges down to a single electron. These advances brought semiconductor nanowires to the forefront of efforts to realize topological superconductivity and Majorana modes. A prime challenge to benefit from the topological properties of Majoranas is to reduce the disorder in hybrid nanowire devices. Here we show ballistic superconductivity in InSb semiconductor nanowires. Our structural and chemical analyses demonstrate a high-quality interface between the nanowire and a NbTiN superconductor that enables ballistic transport. This is manifested by a quantized conductance for normal carriers, a strongly enhanced conductance for Andreev-reflecting carriers, and an induced hard gap with a significantly reduced density of states. These results pave the way for disorder-free Majorana devices.

  7. Ignition of a granular propellant bed

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wildegger-Gaissmaier, A.E.; Johnston, I.R.

    1996-08-01

    An experimental and theoretical study is reported on the ignition process of a low vulnerability ammunition (LOVA) propellant bed in a 127-mm (5-in) bore gun charge. The theoretical investigation was with a two-phase flow interior ballistics code and the model predictions showed the marked influence the igniter system can have on pressure wave development, flame spreading, and the overall interior ballistics performance. A number of different igniter systems were investigated in an empty and propellant-filled gun simulator. Pressure, flame spreading, and high-speed film records were used to analyze the ignition/combustion event. The model predictions for flame spreading were confirmed qualitativelymore » by the experimental data. Full-scale instrumented gun firings were conducted with the optimized igniter design. Pressure waves were not detected in the charge during the firings. Model predictions on overall interior ballistics performance agreed well with the firing data.« less

  8. Opportunities for ballistic missions to Halley's comet

    NASA Technical Reports Server (NTRS)

    Farquhar, R. W.; Wooden, W. H., II

    1977-01-01

    Alternative strategies for ballistic missions to Halley's comet in 1985-86 are described. It is shown that a large science return would be acquired from a ballistic Halley intercept in spite of the high flyby speeds of almost 60 km/sec that are associated with this mission mode. The possibility of retargeting the cometary spacecraft to additional comets after the Halley intercept also exists. In one scenario two cometary spacecraft of identical design would be used to carry out four separate cometary encounters over a three-year period. One spacecraft would intercept Halley before its perihelion passage in December 1985 and then go on to comet Borrelly witn an encounter in January 1988. The other spacecraft would be targeted for a post-perihelion Halley intercept in March 1986 before proceeding towards an encounter with comet Tempel-2 in September 1988. The flyby speeds for the Borrelly and Tempel-2 intercepts are 21 and 13 km/sec, respectively.

  9. Comparative microstructures and cytotoxicity assays for ballistic aerosols composed of micrometals and nanometals: respiratory health implications

    PubMed Central

    Machado, Brenda I; Suro, Raquel M; Garza, Kristine M; Murr, Lawrence E

    2011-01-01

    Aerosol particulates collected on filters from ballistic penetration and erosion events for W–Ni–Co and W–Ni–Fe kinetic energy rod projectiles penetrating steel target plates were observed to be highly cytotoxic to human epithelial A549 lung cells in culture after 48 hours of exposure. The aerosol consisted of micron-sized Fe particulates and nanoparticulate aggregates consisting of W, Ni or W, Co, and some Fe, characterized by scanning electron microscopy and transmission electron microscopy, and using energy-dispersive (X-ray) spectrometry for elemental analysis and mapping. Cytotoxic assays of manufactured micron-sized and nanosized metal particulates of W, Ni, Fe, and Co demonstrated that, consistent with many studies in the literature, only the nanoparticulate elements demonstrated measurable cytotoxicity. These results suggest the potential for very severe, short-term, human toxicity, in particular to the respiratory system on inhaling ballistic aerosols. PMID:21499416

  10. A new nonpenetrating ballistic injury.

    PubMed

    Carroll, A W; Soderstrom, C A

    1978-12-01

    A new, nonpenetrating ballistic injury mechanism involving individuals protected by soft body armor is described. Experimental studies using laboratory animals have demonstrated that despite stopping missile penetration, the heart, liver, spleen, and spinal cord are vulnerable to injury. The rapid jolting force of an impacting bullet is contrasted with the usually encountered mechanisms producing blunt trauma injury. The experimental methodology used to assess a 20% increase in survival probability and an 80% decrease in the need for surgical intervention with a new soft body armor is reviewed. Five cases of ballistic assaults on law enforcement personnel protected by soft body armor are presented. Four emphasize the potentially lifesaving qualities of the armor, while the fifth indicates the need for torso encircling design. Hospitalization should follow all assaults, regardless of the innocuous appearance of the skin lesion and the apparent well being on the assaulted individual. Therapeutic guidelines for patient management are suggested.

  11. Analysis of ballistic transport in nanoscale devices by using an accelerated finite element contact block reduction approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, H.; Li, G., E-mail: gli@clemson.edu

    2014-08-28

    An accelerated Finite Element Contact Block Reduction (FECBR) approach is presented for computational analysis of ballistic transport in nanoscale electronic devices with arbitrary geometry and unstructured mesh. Finite element formulation is developed for the theoretical CBR/Poisson model. The FECBR approach is accelerated through eigen-pair reduction, lead mode space projection, and component mode synthesis techniques. The accelerated FECBR is applied to perform quantum mechanical ballistic transport analysis of a DG-MOSFET with taper-shaped extensions and a DG-MOSFET with Si/SiO{sub 2} interface roughness. The computed electrical transport properties of the devices obtained from the accelerated FECBR approach and associated computational cost as amore » function of system degrees of freedom are compared with those obtained from the original CBR and direct inversion methods. The performance of the accelerated FECBR in both its accuracy and efficiency is demonstrated.« less

  12. Observation of strong reflection of electron waves exiting a ballistic channel at low energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vaz, Canute I.; Campbell, Jason P.; Ryan, Jason T.

    2016-06-15

    Wave scattering by a potential step is a ubiquitous concept. Thus, it is surprising that theoretical treatments of ballistic transport in nanoscale devices, from quantum point contacts to ballistic transistors, assume no reflection even when the potential step is encountered upon exiting the device. Experiments so far seem to support this even if it is not clear why. Here we report clear evidence of coherent reflection when electron wave exits the channel of a nanoscale transistor and when the electron energy is low. The observed behavior is well described by a simple rectangular potential barrier model which the Schrodinger’s equationmore » can be solved exactly. We can explain why reflection is not observed in most situations but cannot be ignored in some important situations. Our experiment also represents a direct measurement of electron injection velocity - a critical quantity in nanoscale transistors that is widely considered not measurable.« less

  13. Spin diffusion from an inhomogeneous quench in an integrable system.

    PubMed

    Ljubotina, Marko; Žnidarič, Marko; Prosen, Tomaž

    2017-07-13

    Generalized hydrodynamics predicts universal ballistic transport in integrable lattice systems when prepared in generic inhomogeneous initial states. However, the ballistic contribution to transport can vanish in systems with additional discrete symmetries. Here we perform large scale numerical simulations of spin dynamics in the anisotropic Heisenberg XXZ spin 1/2 chain starting from an inhomogeneous mixed initial state which is symmetric with respect to a combination of spin reversal and spatial reflection. In the isotropic and easy-axis regimes we find non-ballistic spin transport which we analyse in detail in terms of scaling exponents of the transported magnetization and scaling profiles of the spin density. While in the easy-axis regime we find accurate evidence of normal diffusion, the spin transport in the isotropic case is clearly super-diffusive, with the scaling exponent very close to 2/3, but with universal scaling dynamics which obeys the diffusion equation in nonlinearly scaled time.

  14. A new nonpenetrating ballistic injury.

    PubMed Central

    Carroll, A W; Soderstrom, C A

    1978-01-01

    A new, nonpenetrating ballistic injury mechanism involving individuals protected by soft body armor is described. Experimental studies using laboratory animals have demonstrated that despite stopping missile penetration, the heart, liver, spleen, and spinal cord are vulnerable to injury. The rapid jolting force of an impacting bullet is contrasted with the usually encountered mechanisms producing blunt trauma injury. The experimental methodology used to assess a 20% increase in survival probability and an 80% decrease in the need for surgical intervention with a new soft body armor is reviewed. Five cases of ballistic assaults on law enforcement personnel protected by soft body armor are presented. Four emphasize the potentially lifesaving qualities of the armor, while the fifth indicates the need for torso encircling design. Hospitalization should follow all assaults, regardless of the innocuous appearance of the skin lesion and the apparent well being on the assaulted individual. Therapeutic guidelines for patient management are suggested. Images Fig. 1. Fig. 2. Fig. 3. PMID:736653

  15. Micrometer-Scale Ballistic Transport of Electron Pairs in LaAlO_{3}/SrTiO_{3} Nanowires.

    PubMed

    Tomczyk, Michelle; Cheng, Guanglei; Lee, Hyungwoo; Lu, Shicheng; Annadi, Anil; Veazey, Joshua P; Huang, Mengchen; Irvin, Patrick; Ryu, Sangwoo; Eom, Chang-Beom; Levy, Jeremy

    2016-08-26

    High-mobility complex-oxide heterostructures and nanostructures offer new opportunities for extending the paradigm of quantum transport beyond the realm of traditional III-V or carbon-based materials. Recent quantum transport investigations with LaAlO_{3}/SrTiO_{3}-based quantum dots reveal the existence of a strongly correlated phase in which electrons form spin-singlet pairs without becoming superconducting. Here, we report evidence for the micrometer-scale ballistic transport of electron pairs in quasi-1D LaAlO_{3}/SrTiO_{3} nanowire cavities. In the paired phase, Fabry-Perot-like quantum interference is observed, in sync with conductance oscillations observed in the superconducting regime (at a zero magnetic field). Above a critical magnetic field B_{p}, the electron pairs unbind and the conductance oscillations shift with the magnetic field. These experimental observations extend the regime of ballistic electronic transport to strongly correlated phases.

  16. Finite element analysis for the evaluation of protective functions of helmets against ballistic impact.

    PubMed

    Lee, H P; Gong, S W

    2010-10-01

    The ballistic impact of a human head model protected by a Personnel Armor System Ground Troops Kevlar® helmet is analysed using the finite element method. The emphasis is to examine the effect of the interior cushioning system as a shock absorber in mitigating ballistic impact to the head. The simulations of the frontal and side impacts of the full metal jacket (FMJ) and fragment-simulating projectile (FSP) were carried out using LS-DYNA. It was found that the Kevlar® helmet with its interior nylon and leather strap was able to defeat both the FMJ and FSP without the projectiles penetrating the helmet. However, the head injuries caused by the FMJ impact can be fatal due to the high stiffness of the interior strap. The bulge section at the side of the Kevlar® helmet had more room for deformation that resulted in less serious head injuries.

  17. Propellant development for the Advanced Solid Rocket Motor

    NASA Technical Reports Server (NTRS)

    Landers, L. C.; Stanley, C. B.; Ricks, D. W.

    1991-01-01

    The properties of a propellant developed for the NASA Advanced Solid Rocket Motor (ASRM) are described in terms of its composition, performance, and compliance to NASA specifications. The class 1.3 HTPB/AP/A1 propellant employs an ester plasticizer and the content of ballistic solids is set at 88 percent. Ammonia evolution is prevented by the utilization of a neutral bonding agent which allows continuous mixing. The propellant also comprises a bimodal AP blend with one ground fraction, ground AP of at least 20 microns, and ferric oxide to control the burning rate. The propellant's characteristics are discussed in terms of tradeoffs in AP particle size and the types of Al powder, bonding agent, and HTPB polymer. The size and shape of the ballistic solids affect the processability, ballistic properties, and structural properties of the propellant. The revised baseline composition is based on maximizing the robustness of in-process viscosity, structural integrity, and burning-rate tailoring range.

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

    NASA Astrophysics Data System (ADS)

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

    2012-08-01

    The armour of vehicles against conventional threats is mainly composed with steel or aluminium panels. Efficient heavy solutions exist, but the involved industries require new lightweight structures. Moreover, unconventional threats as IEDs (Improvised Explosive Devices) may cause severe damages on these structural and protective panel solutions. Thus, combination of aluminium or steel plates with textile composite structures used as a backing, leads to the mass reduction and better performance under delamination behaviour against these new threats. This paper is a part of a study dealing with the impact behaviour of three warp interlocks weaving structures under Fragment Simulating Projectile (FSP) impact. During this research, several parameters has being studied as the influence of the yarns insertions [1-4], the degradation of the yarns during the weaving process [5-7], and the influence of the resin rate on the ballistic behaviour. The resin rate inside composite materials is dependant on the final application. In ballistic protection, we need to control the resin rate in order to have a deformable structure in order to absorb the maximum of energy. However, with the warp interlocks weaving structure, the yarns insertions induce empty spaces between the yarns where the resin takes place without being evacuated. The resin rate inside the warp interlocks structures is in the most of cases less than 50%, which lead to have brittle and hard material during the impact. Contrary to interlocks structures, the existing protection based on prepreg structure have a high fibres ratio around 88% of weight. That leads to have the best ballistic properties during the impact and good deformability of the structure. The aim of this paper is to evaluate the influence of the resin rate on the ballistic results of the composites materials. For that, we have chosen two kinds of warp interlocks fabrics which were infused with epoxy resin following two processes. The first is a classical vacuum resin infusion; the second used a press in order to reach a resin ratio near to the existing protection. The existing protection is a prepreg structure with a fibre content of 88%. It has been revealed that a resin rate less than 35% inside the warp interlocks composite material leads to have equivalent ballistics performances than existing protection.

  19. Experimental evaluation of ballistic hazards in imaging diagnostic center.

    PubMed

    Karpowicz, Jolanta; Gryz, Krzysztof

    2013-04-01

    Serious hazards for human health and life and devices in close proximity to the magnetic resonance scanners (MRI scanners) include the effects of being hit by ferromagnetic objects attracted by static magnetic field (SMF) produced by scanner magnet - the so-called ballistic hazards classified among indirect electromagnetic hazards. International safety guidelines and technical literature specify different SMF threshold values regarding ballistic hazards - e.g. 3 mT (directive 2004/40/EC, EN 60601-2-33), and 30 mT (BMAS 2009, directive proposal 2011). Investigations presented in this article were performed in order to experimentally verify SMF threshold for ballistic hazards near MRI scanners used in Poland. Investigations were performed with the use of a laboratory source of SMF (0-30 mT) and MRI scanners of various types. The levels of SMF in which metal objects of various shapes and 0.4-500 g mass are moved by the field influence were investigated. The distance from the MRI scanners (0.2-3T) where hazards may occur were also investigated. Objects investigated under laboratory conditions were moved by SMF of 2.2-15 mT magnetic flux density when they were freely suspended, but were moved by the SMF of 5.6-22 mT when they were placed on a smooth surface. Investigated objects were moved in fields of 3.5-40 mT by MRI scanners. Distances from scanner magnet cover, where ballistic hazards might occur are: up to 0.5 m for 0.2-0.3T scanners; up to 1.3 m for 0.5T scanners; up to 2.0 m for 1.5T scanners and up to 2.5 m for 3T scanners (at the front and back of the magnet). It was shown that SMF of 3 mT magnetic flux density should be taken as the threshold for ballistic hazards. Such level is compatible with SMF limit value regarding occupational safety and health-protected areas/zones, where according to the Polish labor law the procedures of work environment inspection and prevention measures regarding indirect electromagnetic hazards should be applied. Presented results do not support the increase up to 30 mT of the SMF limit for protected area.

  20. Early Rockets

    NASA Image and Video Library

    2004-04-15

    Engine for the Jupiter rocket. The Jupiter vehicle was a direct derivative of the Redstone. The Army Ballistic Missile Agency (ABMA) at Redstone Arsenal, Alabama, continued Jupiter development into a successful intermediate ballistic missile, even though the Department of Defense directed its operational development to the Air Force. ABMA maintained a role in Jupiter RD, including high-altitude launches that added to ABMA's understanding of rocket vehicle operations in the near-Earth space environment. It was knowledge that paid handsome dividends later.

  1. Inroads in the Non-Invasive Diagnostics of Ballistic Impact Damage

    DTIC Science & Technology

    2006-11-01

    2004; Wells, et al., 2002), Ti - 6Al - 4V metallic armor materials (Wells, et al., 2004) and, most recently, on a ballistic gelatin target (Wells, 2006...spiral cracking outside of the penetration cavity in a Ti - 6Al - 4V sample disk. This type of volumetric damage characterization information, otherwise...visualization of the penetration cavity and spiral cracking in a Ti - 6Al - 4V sample. 4 Figure 8. Quantitative 3-D unit damage fraction

  2. Tables of Calculated Transition Probabilities for the A-X System of OH

    DTIC Science & Technology

    1981-06-01

    June 1981 US ARMY ARMAMENT RESEARCH AND DEVELOPMENT COMMAND BALLISTIC RESEARCH LABORATORY ABERDEEN PROVING GROUND , MARYLAND Approved for public release...Laboratory ATTN: DRDAR-BLP Aberdeen Proving Ground , MD 21005 1L16112AH43 II. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE USA Armament Research and...Development Command /I JUNE. 1981 USA Ballistic Research Laboratory 4 ATTN: DRDAR-BL 1/1) S 2P’GE Aberden Provine Ground . MD 21001 56 Pazes 14

  3. Theoretical Prediction of Vibrational Circular Dichroism Spectra

    DTIC Science & Technology

    1990-01-01

    Chabalowski U.S. ARMY BALLISTIC RESEARCH LABORATORY January 1990 DTIC ELECTESMAR 6U99 CHEMICAL COMMAN4D Aberden Proving Ground . MeMand 21010-5423 IDWPM...TASK [WORK UNIT ELEMENT NO. NO.11 46 2 6 2 2 NO. A5531 ACCESSION NO. Aberdeen Proving Ground , MD 21010-5423 IC4648061 D020 1 11. TITLE (Include...Engineering Center ATITN: SDCCR-RSP-C Aberdeen Proving Ground , MD 21010-5423 U.S. Army Ballistic Research Laboratory Aberdeen Proving Ground , MD

  4. Orbital Debris Shape and Orientation Effects on Ballistic Limits

    NASA Technical Reports Server (NTRS)

    Evans, Steven W.; Williamsen, Joel E.

    2005-01-01

    The SPHC hydrodynamic code was used to evaluate the effects of orbital debris particle shape and orientation on penetration of a typical spacecraft dual-wall shield. Impacts were simulated at near-normal obliquity at 12 km/sec. Debris cloud characteristics and damage potential are compared with those from impacts by spherical projectiles. Results of these simulations indicate the uncertainties in the predicted ballistic limits due to modeling uncertainty and to uncertainty in the impactor orientation.

  5. Navy Columbia Class (Ohio Replacement) Ballistic Missile Submarine (SSBN[X]) Program: Background and Issues for Congress

    DTIC Science & Technology

    2016-10-03

    of UK design and manufacture . 12 For more on the arrangement for jointly building Virginia- class boats, see CRS Report RL32418, Navy Virginia (SSN...lines would result in a cumulative one year schedule reduction in Missile Tube Module manufacturing for the OR Class . This schedule reduction, on a...Navy Columbia Class (Ohio Replacement) Ballistic Missile Submarine (SSBN[X]) Program: Background and Issues for Congress Ronald O’Rourke

  6. Direct determination of energy level alignment and charge transport at metal-Alq3 interfaces via ballistic-electron-emission spectroscopy.

    PubMed

    Jiang, J S; Pearson, J E; Bader, S D

    2011-04-15

    Using ballistic-electron-emission spectroscopy (BEES), we directly determined the energy barrier for electron injection at clean interfaces of Alq(3) with Al and Fe to be 2.1 and 2.2 eV, respectively. We quantitatively modeled the sub-barrier BEES spectra with an accumulated space charge layer, and found that the transport of nonballistic electrons is consistent with random hopping over the injection barrier.

  7. Air Force Intercontinental Ballistic Missile Fuze Modernization (ICBM Fuze Mod)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report ( SAR ) RCS: DD-A&T(Q&A)823-498 Air Force Intercontinental Ballistic Missile Fuze Modernization (ICBM Fuze Mod) As of FY...2015 SAR March 17, 2016 09:03:03 UNCLASSIFIED 2 Table of Contents Common Acronyms and Abbreviations for MDAP Programs 3 Program Information...Acquisition Unit Cost ICBM Fuze Mod December 2015 SAR March 17, 2016 09:03:03 UNCLASSIFIED 3 PB - President’s Budget PE - Program Element PEO - Program

  8. Strategic Stability Through the Strategic Defense Initiative

    DTIC Science & Technology

    1989-03-09

    Alliance, pp. 35-36. 23. Ibid. 24. Ibid., p. 37. 25. Steven P. Adragna , On Guard for Victory: Military Doctrine and Ballistic Missile Defense in the USSR...their fundamental policy of survival of the motherland. ENDNOTES 1. Steven P. Adragna , On Guard for Victory: Military Doctrine and Ballistic Missile...Approach to Nuclear Arms Control," Survival, Nov/Dee 1987, p. 494. 5. Adragna , p. 59. 6. Rivkin, p. 495. 7. Johnson, p. 184. 8. Senator Malcomb Wallop

  9. The Aegis BMD Global Enterprise: A High End Maritime Partnership

    DTIC Science & Technology

    2016-04-13

    have been dealing with ballistic-missile defense through the alliance’s Active Layered Theatre Ballistic Missile Defence (ALTBMD) program and, since...Defense Agency (MDA) budgets.18 The twenty-fifth test— designated Flight Test Mission (FTM) 15—occurred on 15 April 2011, when the MDA conducted the...original design , which focused on short- and medium-range threats. The LV-2 had flown in two previous BMD live-fire tests but had not been hit—until FTM

  10. Conventional Prompt Global Strike and Long-Range Ballistic Missiles: Background and Issues

    DTIC Science & Technology

    2013-04-26

    developing scramjet — supersonic combustion ramjet—technologies that may contribute to the long-range strike mission in the future. In this type of vehicle ... vehicle that could deploy on a modified Peacekeeper land- based ballistic missile—a system known as the Conventional Strike Missile (CSM). In FY2008...into the Air Force CSM and two possible hypersonic glide vehicles . Congress appropriated $174.8 million for CPGS capability development in FY2012. DOD

  11. Microwave Semiconductor Research - Materials, Devices and Circuits and Gallium Arsenide Ballistic Electron Transistors.

    DTIC Science & Technology

    1985-04-01

    activation energies than previously possible. Electron traps and hole traps with energies less than 50 meV were observed for the first time in GaAs...developed in our laboratory to photoexcite electrons in a given energy range in the conduction band and then measure the relaxation of these carriers...limitations on the electron energy may be required. CURRENT AND FUTURE EFFORTS The possibility of ballistic electron transport in gallium arsenide has been

  12. Design of a Combined Ballistic Simulator and Primer Force Experimental Fixture

    DTIC Science & Technology

    2015-08-01

    preload bolt and breech, and between the breech and chamber, were found to be too loose. When heavy grease or Teflon tape was used to tighten the...increase the difficulty of removing and tightening the breech. The preload bolt does not have to be removed between firing and in future designs could use... tightened it could loosen the primer plate, so left-handed threads were machined on the primer plate. The ballistic simulator fixture was occasionally

  13. The Mechanical Metallurgy of Armour Steels

    DTIC Science & Technology

    2016-10-01

    Group -TR-3305 UNCLASSIFIED 7 Figure 5: Linear relationship between quasi -static tensile yield stress and ballistic limit...te d Ba lli st ic L im it (m /s ) Experimental Ballistic Limit (m/s) UNCLASSIFIED DST- Group -TR-3305 UNCLASSIFIED 9 flow stress with strain...1000 1500 2000 2500 3000 0 0.2 0.4 0.6 0.8 Tr ue S tr es s (M Pa ) True Strain Quasi -static Dynamic RHA HHA UHHA UNCLASSIFIED DST- Group

  14. Axial-Compressive Behavior, Including Kink-Band Formation and Propagation, of Single p-Phenylene Terephthalamide (PPTA) Fibers

    DTIC Science & Technology

    2013-01-01

    material models to describe the behavior of fibers and structures under high -rate loading conditions. With the utility of the CAE methods and tools largely...phenylene terephthalamide (PPTA), available commercially as Kevlar, Twaron, Technora, and so forth, are characterized by high specific axial stiffness...and high specific tensile strength. These fibers are often referred to as “ballistic fibers” since they are commonly used in different ballistic- and

  15. Direct determination of energy level alignment and charge transport at metal/Alq{sub 3} interfaces via ballistic-electron-emission spectroscopy.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jiang, J. S.; Pearson, J. E.; Bader, S. D.

    2011-04-15

    Using ballistic-electron-emission spectroscopy (BEES), we directly determined the energy barrier for electron injection at clean interfaces of Alq{sub 3} with Al and Fe to be 2.1 and 2.2 eV, respectively. We quantitatively modeled the sub-barrier BEES spectra with an accumulated space charge layer, and found that the transport of nonballistic electrons is consistent with random hopping over the injection barrier.

  16. Electrothermal-Chemical Modeling and Diagnostics Workshop. Volume 1

    DTIC Science & Technology

    1991-10-01

    z ox IOX OLVox 110~ Table 2: Summary of the theorctical rcsuilts (J Powell and Zielinski (ideal plasma) Shot VTr T P.’ 4 Volts (cV) (.Pa) (. m) 2 1221...Gloria P. Wren Ballistic Research Laboratory ATTN: SLCBR-IB-B Aberdeen Proving Ground, MD 21005-5066 (301) 278-6199 Mr. Alex Zielinski Ballistic Research...Park Road, SE Warren, MI 48090-2074 Albuquerque, NM 87106 General Dynamics Land Systems Division 1 Teledyne Brown Engineering ATTN: Dave Toepler ATTN

  17. Another Brick in the Wall: The Israeli Experience in Missile Defense

    DTIC Science & Technology

    2015-04-01

    region. In particular, the way the Is- raelis decapitated the Egyptian Air Force on June 5 in only 3 hours engendered tremendous awe among the Arab...in a memo, “Iraq has the most aggressive and advanced ballistic missile development program in the Arab World.”8 Like the Egyptians , the Iraqis...range ballistic missile (SRBM) delivered in 1973 shortly be- fore the war with Israel. Like the Egyptians , the Syr- ians also used their missiles

  18. Upgrades and Modifications of the NASA Ames HFFAF Ballistic Range

    NASA Technical Reports Server (NTRS)

    Bogdanoff, David W.; Wilder, Michael C.; Cornelison, Charles J.; Perez, Alfredo J.

    2017-01-01

    The NASA Ames Hypervelocity Free Flight Aerodynamics Facility ballistic range is described. The various configurations of the shadowgraph stations are presented. This includes the original stations with film and configurations with two different types of digital cameras. Resolution tests for the 3 shadowgraph station configurations are described. The advantages of the digital cameras are discussed, including the immediate availability of the shadowgraphs. The final shadowgraph station configuration is a mix of 26 Nikon cameras and 6 PI-MAX2 cameras. Two types of trigger light sheet stations are described visible and IR. The two gunpowders used for the NASA Ames 6.251.50 light gas guns are presented. These are the Hercules HC-33-FS powder (no longer available) and the St. Marks Powder WC 886 powder. The results from eight proof shots for the two powders are presented. Both muzzle velocities and piston velocities are 5 9 lower for the new St. Marks WC 886 powder than for the old Hercules HC-33-FS powder (no longer available). The experimental and CFD (computational) piston and muzzle velocities are in good agreement. Shadowgraph-reading software that employs template-matching pattern recognition to locate the ballistic-range model is described. Templates are generated from a 3D solid model of the ballistic-range model. The accuracy of the approach is assessed using a set of computer-generated test images.

  19. The mechanics of explosive seed dispersal in orange jewelweed (Impatiens capensis)

    PubMed Central

    Hayashi, Marika; Feilich, Kara L.; Ellerby, David J.

    2009-01-01

    Explosive dehiscence ballistically disperses seeds in a number of plant species. During dehiscence, mechanical energy stored in specialized tissues is transferred to the seeds to increase their kinetic and potential energies. The resulting seed dispersal patterns have been investigated in some ballistic dispersers, but the mechanical performance of a launch mechanism of this type has not been measured. The properties of the energy storage tissue and the energy transfer efficiency of the launch mechanism were quantified in Impatiens capensis. In this species the valves forming the seed pod wall store mechanical energy. Their mass specific energy storage capacity (124 J kg−1) was comparable with that of elastin and spring steel. The energy storage capacity of the pod tissues was determined by their level of hydration, suggesting a role for turgor pressure in the energy storage mechanism. During dehiscence the valves coiled inwards, collapsing the pod and ejecting the seeds. Dehiscence took 4.2±0.4 ms (mean ±SEM, n=13). The estimated efficiency with which energy was transferred to the seeds was low (0.51±0.26%, mean ±SEM, n=13). The mean seed launch angle (17.4±5.2, mean ±SEM, n=45) fell within the range predicted by a ballistic model to maximize dispersal distance. Low ballistic dispersal efficiency or effectiveness may be characteristic of species that also utilize secondary seed dispersal mechanisms. PMID:19321647

  20. The mechanics of explosive seed dispersal in orange jewelweed (Impatiens capensis).

    PubMed

    Hayashi, Marika; Feilich, Kara L; Ellerby, David J

    2009-01-01

    Explosive dehiscence ballistically disperses seeds in a number of plant species. During dehiscence, mechanical energy stored in specialized tissues is transferred to the seeds to increase their kinetic and potential energies. The resulting seed dispersal patterns have been investigated in some ballistic dispersers, but the mechanical performance of a launch mechanism of this type has not been measured. The properties of the energy storage tissue and the energy transfer efficiency of the launch mechanism were quantified in Impatiens capensis. In this species the valves forming the seed pod wall store mechanical energy. Their mass specific energy storage capacity (124 J kg(-1)) was comparable with that of elastin and spring steel. The energy storage capacity of the pod tissues was determined by their level of hydration, suggesting a role for turgor pressure in the energy storage mechanism. During dehiscence the valves coiled inwards, collapsing the pod and ejecting the seeds. Dehiscence took 4.2+/-0.4 ms (mean +/-SEM, n=13). The estimated efficiency with which energy was transferred to the seeds was low (0.51+/-0.26%, mean +/-SEM, n=13). The mean seed launch angle (17.4+/-5.2, mean +/-SEM, n=45) fell within the range predicted by a ballistic model to maximize dispersal distance. Low ballistic dispersal efficiency or effectiveness may be characteristic of species that also utilize secondary seed dispersal mechanisms.

  1. Management of High-energy Avulsive Ballistic Facial Injury: A Review of the Literature and Algorithmic Approach.

    PubMed

    Vaca, Elbert E; Bellamy, Justin L; Sinno, Sammy; Rodriguez, Eduardo D

    2018-03-01

    High-energy avulsive ballistic facial injuries pose one of the most significant reconstructive challenges. We conducted a systematic review of the literature to evaluate management trends and outcomes for the treatment of devastating ballistic facial trauma. Furthermore, we describe the senior author's early and definitive staged reconstructive approach to these challenging patients. A Medline search was conducted to include studies that described timing of treatment, interventions, complications, and/or aesthetic outcomes. Initial query revealed 41 articles, of which 17 articles met inclusion criteria. A single comparative study revealed that early versus delayed management resulted in a decreased incidence of soft-tissue contracture, required fewer total procedures, and resulted in shorter hospitalizations (level 3 evidence). Seven of the 9 studies (78%) that advocated delayed reconstruction were from the Middle East, whereas 5 of the 6 studies (83%) advocating immediate or early definitive reconstruction were from the United States. No study compared debridement timing directly in a head-to-head fashion, nor described flap selection based on defect characteristics. Existing literature suggests that early and aggressive intervention improves outcomes following avulsive ballistic injuries. Further comparative studies are needed; however, although evidence is limited, the senior author presents a 3-stage reconstructive algorithm advocating early and definitive reconstruction with aesthetic free tissue transfer in an attempt to optimize reconstructive outcomes of these complex injuries.

  2. A fully synthetic lung model for wound-ballistic experiments-First results.

    PubMed

    Bolliger, S A; Poschmann, S A; Thali, M J; Eggert, S

    2017-06-01

    Today, synthetic models have all but replaced animal and corpse models in examining damage to soft-tissues and skeletal structures by ballistic trauma. As, however, non-solid organs such as the lungs, have not been able to be replaced by a fully synthetic model we attempted to create such a model. 20% ordnance gelatine was frothed with a household mixer and cooled to stable foam. Several of these foam blocks were then stuck together with liquid gelatine and placed between 10% gelatine blocks. As controls, we embedded pig lungs in gelatine and compared the wound channels seen in computed tomography created upon shooting with 9mm Luger. The fully synthetic models displayed radiological and physical densities comparable to real lungs. The wound profile characteristics of the fully synthetic lung models were very similar to the semisynthetic swine-gelatine models regarding the permanent wound cavity. Furthermore, in both semi- and fully synthetic models we detected a ring surrounding the permanent wound channel, most likely representing the remnants of the temporary wound cavity. Our results indicate that this fully synthetic lung model is a viable substitute for ballistic experiments on lungs. We believe that further research on the temporary wound channel in lungs is possible with this model in order to provide more insight into the effect of ballistic trauma to the lungs not seen otherwise. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Management of High-energy Avulsive Ballistic Facial Injury: A Review of the Literature and Algorithmic Approach

    PubMed Central

    Vaca, Elbert E.; Bellamy, Justin L.; Sinno, Sammy

    2018-01-01

    Background: High-energy avulsive ballistic facial injuries pose one of the most significant reconstructive challenges. We conducted a systematic review of the literature to evaluate management trends and outcomes for the treatment of devastating ballistic facial trauma. Furthermore, we describe the senior author’s early and definitive staged reconstructive approach to these challenging patients. Methods: A Medline search was conducted to include studies that described timing of treatment, interventions, complications, and/or aesthetic outcomes. Results: Initial query revealed 41 articles, of which 17 articles met inclusion criteria. A single comparative study revealed that early versus delayed management resulted in a decreased incidence of soft-tissue contracture, required fewer total procedures, and resulted in shorter hospitalizations (level 3 evidence). Seven of the 9 studies (78%) that advocated delayed reconstruction were from the Middle East, whereas 5 of the 6 studies (83%) advocating immediate or early definitive reconstruction were from the United States. No study compared debridement timing directly in a head-to-head fashion, nor described flap selection based on defect characteristics. Conclusions: Existing literature suggests that early and aggressive intervention improves outcomes following avulsive ballistic injuries. Further comparative studies are needed; however, although evidence is limited, the senior author presents a 3-stage reconstructive algorithm advocating early and definitive reconstruction with aesthetic free tissue transfer in an attempt to optimize reconstructive outcomes of these complex injuries. PMID:29707453

  4. Autonomic self-healing in epoxidized natural rubber.

    PubMed

    Rahman, Arifur; Sartore, Luciana; Bignotti, Fabio; Di Landro, Luca

    2013-02-01

    The development of polymers that can repair damage autonomously would be useful to improve the lifetime of polymeric materials. To date, limited attention has been dedicated to developing elastomers with autonomic self-healing ability, which can recover damages without need for an external or internal source of healing agents. This work investigates the self-healing behavior of epoxidized natural rubber (ENR) with two different epoxidation levels (25 and 50 mol % epoxidation) and of the corresponding unfunctionalized rubber, cis-1,4-polyisoprene (PISP). A self-adhesion assisted self-healing behavior was revealed by T-peel tests on slightly vulcanized rubbers. A higher epoxidation level was found to enhance self-healing. Self-healing of rubbers following ballistic damages was also investigated. A pressurized air flow test setup was used to evaluate the self-healing of ballistic damages in rubbers. Microscope (OM, SEM, and TEM) analyses were carried out to provide further evidence of healing in the impact zones. Self-healing of ballistic damages was observed only in ENR with 50 mol % epoxidation and it was found to be influenced significantly by the cross-link density. Finally, self-healing of ballistic damages was also observed in ENR50/PISP blends only when the content of the healing component (i.e., ENR50) was at least 25 wt %. From an analysis of the results, it was concluded that a synergistic effect between interdiffusion and interaction among polar groups leads to self-healing in ENR.

  5. Effect of low-velocity or ballistic impact damage on the strength of thin composite and aluminum shear panels

    NASA Technical Reports Server (NTRS)

    Farley, G. L.

    1985-01-01

    Impact tests were conducted on shear panels fabricated from 6061-T6 aluminum and from woven fabric prepreg of Du Pont Kevlara fiber/epoxy resin and graphite fiber/epoxy resin. The shear panels consisted of three different composite laminates and one aluminum material configuration. Three panel aspect ratios were evaluated for each material configuration. Composite panels were impacted with a 1.27-cm (0.05-in) diameter aluminum sphere at low velocities of 46 m/sec (150 ft/sec) and 67 m/sec (220 ft/sec). Ballistic impact conditions consisted of a tumbled 0.50-caliber projectile impacting loaded composite and aluminum shear panels. The results of these tests indicate that ballistic threshold load (the lowest load which will result in immediate failure upon penetration by the projectile) varied between 0.44 and 0.61 of the average failure load of undamaged panels. The residual strengths of the panels after ballistic impact varied between 0.55 and 0.75 of the average failure strength of the undamaged panels. The low velocity impacts at 67 m/sec (220 ft/sec) caused a 15 to 20 percent reduction in strength, whereas the impacts at 46 m/sec (150 ft/sec) resulted in negligible strength loss. Good agreement was obtained between the experimental failure strengths and the predicted strength with the point stress failure criterion.

  6. Relationships Between Potentiation Effects After Ballistic Half-Squats and Bilateral Symmetry.

    PubMed

    Suchomel, Timothy J; Sato, Kimitake; DeWeese, Brad H; Ebben, William P; Stone, Michael H

    2016-05-01

    The purposes of this study were to examine the effect of ballistic concentric-only half-squats (COHS) on subsequent squat-jump (SJ) performances at various rest intervals and to examine the relationships between changes in SJ performance and bilateral symmetry at peak performance. Thirteen resistance-trained men performed an SJ immediately and every minute up to 10 min on dual force plates after 2 ballistic COHS repetitions at 90% of their 1-repetition-maximum COHS. SJ peak force, peak power, net impulse, and rate of force development (RFD) were compared using a series of 1-way repeated-measures ANOVAs. The percent change in performance at which peak performance occurred for each variable was correlated with the symmetry index scores at the corresponding time point using Pearson correlation coefficients. Statistical differences in peak power (P = .031) existed between rest intervals; however, no statistically significant pairwise comparisons were present (P > .05). No statistical differences in peak force (P = .201), net impulse (P = .064), and RFD (P = .477) were present between rest intervals. The relationships between changes in SJ performance and bilateral symmetry after the rest interval that produced the greatest performance for peak force (r = .300, P = .319), peak power (r = -.041, P = .894), net impulse (r = -.028, P = .927), and RFD (r = -.434, P = .138) were not statistically significant. Ballistic COHS may enhance SJ performance; however, the changes in performance were not related to bilateral symmetry.

  7. Signature analysis of ballistic missile warhead with micro-nutation in terahertz band

    NASA Astrophysics Data System (ADS)

    Li, Ming; Jiang, Yue-song

    2013-08-01

    In recent years, the micro-Doppler effect has been proposed as a new technique for signature analysis and extraction of radar targets. The ballistic missile is known as a typical radar target and has been paid many attentions for the complexities of its motions in current researches. The trajectory of a ballistic missile can be generally divided into three stages: boost phase, midcourse phase and terminal phase. The midcourse phase is the most important phase for radar target recognition and interception. In this stage, the warhead forms a typical micro-motion called micro-nutation which consists of three basic micro-motions: spinning, coning and wiggle. This paper addresses the issue of signature analysis of ballistic missile warhead in terahertz band via discussing the micro-Doppler effect. We establish a simplified model (cone-shaped) for the missile warhead followed by the micro-motion models including of spinning, coning and wiggle. Based on the basic formulas of these typical micro-motions, we first derive the theoretical formula of micro-nutation which is the main micro-motion of the missile warhead. Then, we calculate the micro-Doppler frequency in both X band and terahertz band via these micro-Doppler formulas. The simulations are given to show the superiority of our proposed method for the recognition and detection of radar micro targets in terahertz band.

  8. Wound ballistics 101: the mechanisms of soft tissue wounding by bullets.

    PubMed

    Stefanopoulos, P K; Pinialidis, D E; Hadjigeorgiou, G F; Filippakis, K N

    2017-10-01

    The mechanisms of soft tissue injury by bullets are reviewed, in the belief that the current incidence of firearm injuries in many urban areas necessitates an understanding of wound ballistics on the part of trauma surgeons who may not be familiar with the wounding factors involved. Review of the literature, with technical information obtained from appropriate non-medical texts. Despite numerous publications concerning the treatment of gunshot wounds, relatively few papers contain details on the mechanisms of ballistic trauma, with the main body of evidence derived from previous laboratory and animal studies which have only recently been systematically appraised. These studies have shown that in rifle injuries the main wound tract is surrounded by an area of damaged tissue as a result of the temporary cavitation induced once the bullet becomes destabilized or deformed. On the other hand, the more commonly encountered non-deforming handgun bullets cause damage limited to the bullet's path, mainly as a result of localized crush injury. The bullet's construction and ballistic behavior within tissue determine to what extent the previously overestimated velocity factor may influence wound severity. The damage produced from temporary cavitation depends on the tensile properties of the tissues involved, and in high-energy injuries may lead to progressive muscle tissue necrosis. Therefore, the term "high-energy" should be reserved for those injuries with substantial tissue damage extending beyond the visible wound tract.

  9. Force-Velocity Relationship of Upper Body Muscles: Traditional Versus Ballistic Bench Press.

    PubMed

    García-Ramos, Amador; Jaric, Slobodan; Padial, Paulino; Feriche, Belén

    2016-04-01

    This study aimed to (1) evaluate the linearity of the force-velocity relationship, as well as the reliability of maximum force (F0), maximum velocity (V0), slope (a), and maximum power (P0); (2) compare these parameters between the traditional and ballistic bench press (BP); and (3) determine the correlation of F0 with the directly measured BP 1-repetition maximum (1RM). Thirty-two men randomly performed 2 sessions of traditional BP and 2 sessions of ballistic BP during 2 consecutive weeks. Both the maximum and mean values of force and velocity were recorded when loaded by 20-70% of 1RM. All force-velocity relationships were strongly linear (r > .99). While F0 and P0 were highly reliable (ICC: 0.91-0.96, CV: 3.8-5.1%), lower reliability was observed for V0 and a (ICC: 0.49-0.81, CV: 6.6-11.8%). Trivial differences between exercises were found for F0 (ES: < 0.2), however the a was higher for the traditional BP (ES: 0.68-0.94), and V0 (ES: 1.04-1.48) and P0 (ES: 0.65-0.72) for the ballistic BP. The F0 strongly correlated with BP 1RM (r: 0.915-0.938). The force-velocity relationship is useful to assess the upper body maximal capabilities to generate force, velocity, and power.

  10. Remote ballistic fractures in a gelatine model - aetiology and surgical implications

    PubMed Central

    2013-01-01

    Background Remote ballistic femoral fractures are rare fractures reported in the literature but still debated as to their existence and, indeed, their treatment. This study aimed to prove their existence, understand how they occur and determine which ammunition provides the greatest threat. In addition, fracture patterns, soft tissue disruption and contamination were assessed to aid in treatment planning. Method We filmed 42 deer femora embedded in ballistic gelatine and shot with four different military (5.56 × 45 mm, 7.62 × 39 mm) and civilian (9 × 19 mm, .44 in.) bullets, at varying distances off the bone (0–10 cm). Results Two remote ballistic fractures occurred, both with .44 in. hollow-point bullets shot 3 cm off the bone. These fractures occurred when the leading edge of the expanding temporary cavity impacted the femur's supracondylar region, producing a wedge-shaped fracture with an undisplaced limb, deceivingly giving the appearance of a spiral fracture. No communication was seen between the fracture and permanent cavity, despite the temporary cavity encasing the fracture and stripping periosteum from its base. Conclusion These fractures occur with civilian ammunition, but cannot prove their existence with military rounds. They result from the expanding temporary cavity affecting the weakest part of the bone, creating a potentially contaminated wedge-shaped fracture, important for surgeons considering operative intervention. PMID:23721113

  11. The effect of high-pressure devitrification and densification on ballistic-penetration resistance of fused silica

    NASA Astrophysics Data System (ADS)

    Avuthu, Vasudeva Reddy

    Despite the clear benefits offered by more advanced transparent materials, (e.g. transparent ceramics offer a very attractive combination of high stiffness and high hardness levels, highly-ductile transparent polymers provide superior fragment-containing capabilities, etc.), ballistic ceramic-glass like fused-silica remains an important constituent material in a majority of transparent impact-resistant structures (e.g. windshields and windows of military vehicles, portholes in ships, ground vehicles and spacecraft) used today. Among the main reasons for the wide-scale use of glass, the following three are most frequently cited: (i) glass-structure fabrication technologies enable the production of curved, large surface-area, transparent structures with thickness approaching several inches; (ii) relatively low material and manufacturing costs; and (iii) compositional modifications, chemical strengthening, and controlled crystallization have been demonstrated to be capable of significantly improving the ballistic properties of glass. In the present work, the potential of high-pressure devitrification and densification of fused-silica as a ballistic-resistance-enhancement mechanism is investigated computationally. In the first part of the present work, all-atom molecular-level computations are carried out to infer the dynamic response and material microstructure/topology changes of fused silica subjected to ballistic impact by a nanometer-sized hard projectile. The analysis was focused on the investigation of specific aspects of the dynamic response and of the microstructural changes such as the deformation of highly sheared and densified regions, and the conversion of amorphous fused silica to SiO2 crystalline allotropic modifications (in particular, alpha-quartz and stishovite). The microstructural changes in question were determined by carrying out a post-processing atom-coordination procedure. This procedure suggested the formation of high-density stishovite (and perhaps alpha-quartz) within fused silica during ballistic impact. To rationalize the findings obtained, the all-atom molecular-level computational analysis is complemented by a series of quantum-mechanics density functional theory (DFT) computations. The latter computations enable determination of the relative potential energies of the fused silica, alpha-quartz and stishovite under ambient pressure (i.e. under their natural densities) as well as under imposed (as high as 50 GPa) pressures (i.e. under higher densities) and shear strains. In addition, the transition states associated with various fused-silica devitrification processes were identified. In the second part of the present work, the molecular-level computational results obtained in the first portion of the work are used to enrich a continuum-type constitutive model (that is, the so-called Johnson-Holmquist-2, JH2, model) for fused silica. Since the aforementioned devitrification and permanent-densification processes modify the response of fused silica to the pressure as well as to the deviatoric part of the stress, changes had to be made in both the JH2 equation of state and the strength model. To assess the potential improvements with respect to the ballistic-penetration resistance of this material brought about by the fused-silica devitrification and permanent-densification processes, a series of transient non-linear dynamics finite element analyses of the transverse impact of a fused-silica test plate with a solid right-circular cylindrical steel projectile was conducted. The results obtained revealed that, provided the projectile incident velocity and, hence, the attendant pressure, is sufficiently high, fused silica can undergo impact-induced energy-consuming devitrification, which improves its ballistic-penetration resistance.

  12. Ballistic Blocks Surrounding Kilauea's Caldera

    NASA Astrophysics Data System (ADS)

    Swanson, D.; Zolkos, S.; Haravitch, B.

    2010-12-01

    Thousands of lithic blocks dot the surface around Kilauea’s caldera, erupted ballistically at the end of the 1790 eruption or soon thereafter. Most of the blocks occur in the western and southern sectors, probably reflecting the proximity of vents on the caldera floor. We mapped the ejecta field, measuring most of the blocks with nominal diameters ((a+b+c)/3) more than 75 cm and many of the smaller ones, noting distinctive lithologies. The distributions, sizes, and lithologies suggest 7-8 different ballistic bursts from 3-4 generalized vent areas. We measured 15 blocks with nominal diameters (ND) of 150-201 cm, 169 blocks with ND 100-149 cm, 308 blocks with ND 75-99 cm, 684 blocks with ND 50-74 cm, and 545 blocks with ND 25-49 cm. The smaller blocks were measured only in outlying areas, where they were the largest in the neighborhood, but they occur throughout the field. Twelve blocks with ND >150 cm lie within 1.7 km west and south of the center of Halema`uma`u; a vent near this location likely erupted the blocks. Three of the largest blocks, however, are 2.2-2.7 km north of Halema`uma`u and probably came from a more northerly vent. This interpretation is supported by the distributions of all blocks with ND >100 cm, which define at least 4, and possibly 5, different dispersal lobes; three cluster near Halema`uma`u, one is slightly north, and the one with the three large blocks is still farther north. The blocks have typical lithologies for Kilauea’s summit, including coarse basalt or fine gabbro derived from the centers of thick flows, solidified lakes, or small intrusions. Three lithologies are distinctive and help define 3, possibly 4, discrete bursts. Blocks of fine-grained basalt riddled with segregation veins occur only in a lobe 1.3 km wide reaching as far as 1.8 km southwest of Halema`uma`u; this lobe overlaps slightly with one defined by block size but is mostly distinct and probably indicates a separate burst. A cluster of blocks with puffy, somewhat fluidal rinds forms a distinct lobe 800 m wide out to 1.8 km southeast of Halema`uma`u. The cluster also contains many cored bombs and a few juvenile bombs and lapilli without cores. This is the only ballistic lobe that contains much juvenile material, though older fall and surge deposits of 1790 and pre1790 vintage also carry cored bombs and juvenile lapilli. This lobe is coextensive with one defined by block size. The largest ballistic lobe has abundant, commonly oxidized blocks of olivine-rich basalt, some verging on picrite. The main lobe, about 900 m wide, extends 0.9-3.6 km southeast of Halema`uma`u; three olivine-rich blocks between 100 and 150 cm ND occur 2.4 to 3.3 km out. A possible second lobe of olivine-rich blocks occurs out to 1.6 km due south of Halema`uma`u. The lobes indicate a directionality and inclined ejection angle for at least some of the ballistic eruptions, as was true for the observed, but much smaller, ballistic eruptions in 1924. The scarcity of juvenile ejecta argues for phreatic eruptions that were likely initiated at or below the water table, today about 600 m below the caldera rim. If so, some ballistic blocks weighing a few tonnes were thrown at least 600 m above the vent. The dynamics of these explosive eruptions are under study.

  13. Performance of lead-free versus lead-based hunting ammunition in ballistic soap.

    PubMed

    Gremse, Felix; Krone, Oliver; Thamm, Mirko; Kiessling, Fabian; Tolba, René Hany; Rieger, Siegfried; Gremse, Carl

    2014-01-01

    Lead-free hunting bullets are an alternative to lead-containing bullets which cause health risks for humans and endangered scavenging raptors through lead ingestion. However, doubts concerning the effectiveness of lead-free hunting bullets hinder the wide-spread acceptance in the hunting and wildlife management community. We performed terminal ballistic experiments under standardized conditions with ballistic soap as surrogate for game animal tissue to characterize dimensionally stable, partially fragmenting, and deforming lead-free bullets and one commonly used lead-containing bullet. The permanent cavities created in soap blocks are used as a measure for the potential wound damage. The soap blocks were imaged using computed tomography to assess the volume and shape of the cavity and the number of fragments. Shots were performed at different impact speeds, covering a realistic shooting range. Using 3D image segmentation, cavity volume, metal fragment count, deflection angle, and depth of maximum damage were determined. Shots were repeated to investigate the reproducibility of ballistic soap experiments. All bullets showed an increasing cavity volume with increasing deposited energy. The dimensionally stable and fragmenting lead-free bullets achieved a constant conversion ratio while the deforming copper and lead-containing bullets showed a ratio, which increases linearly with the total deposited energy. The lead-containing bullet created hundreds of fragments and significantly more fragments than the lead-free bullets. The deflection angle was significantly higher for the dimensionally stable bullet due to its tumbling behavior and was similarly low for the other bullets. The deforming bullets achieved higher reproducibility than the fragmenting and dimensionally stable bullets. The deforming lead-free bullet closely resembled the deforming lead-containing bullet in terms of energy conversion, deflection angle, cavity shape, and reproducibility, showing that similar terminal ballistic behavior can be achieved. Furthermore, the volumetric image processing allowed superior analysis compared to methods that involve cutting of the soap blocks.

  14. Dynamic knee stability and ballistic knee movement after ACL reconstruction: an application on instep soccer kick.

    PubMed

    Cordeiro, Nuno; Cortes, Nelson; Fernandes, Orlando; Diniz, Ana; Pezarat-Correia, Pedro

    2015-04-01

    The instep soccer kick is a pre-programmed ballistic movement with a typical agonist-antagonist coordination pattern. The coordination pattern of the kick can provide insight into deficient neuromuscular control. The purpose of this study was to investigate knee kinematics and hamstrings/quadriceps coordination pattern during the knee ballistic extension phase of the instep kick in soccer players after anterior cruciate ligament reconstruction (ACL reconstruction). Seventeen players from the Portuguese Soccer League participated in this study. Eight ACL-reconstructed athletes (experimental group) and 9 healthy individuals (control group) performed three instep kicks. Knee kinematics (flexion and extension angles at football contact and maximum velocity instants) were calculated during the kicks. Rectus femoris (RF), vastus lateralis, vastus medialis, biceps femoralis, and semitendinosus muscle activations were quantified during the knee extension phase. The ACL-reconstructed group had significantly lower knee extension angle (-1.2 ± 1.6, p < 0.021) and increased variability (1.1 ± 1.2, p < 0.012) when compared with the control group. Within the EMG variables, the RF had a significantly greater activity in the ACL-reconstructed group than in the control group (79.9 ± 27.7 % MVC vs. 49.2 ± 20.8 % MVC, respectively, p < 0.034). No other statistically significant differences were found. The findings of this study demonstrate that changes in ACL-reconstructed individuals were observed on knee extension angle and RF muscle activation while performing an instep kick. These findings are in accordance with the knee stability recovery process after ACL reconstruction. No differences were observed in the ballistic control movement pattern between normal and ACL-reconstructed subjects. Performing open kinetic chain exercises using ballistic movements can be beneficial when recovering from ACL reconstruction. The exercises should focus on achieving multi-joint coordination and full knee extension (range of motion). III.

  15. Performance of Lead-Free versus Lead-Based Hunting Ammunition in Ballistic Soap

    PubMed Central

    Gremse, Felix; Krone, Oliver; Thamm, Mirko; Kiessling, Fabian; Tolba, René Hany; Rieger, Siegfried; Gremse, Carl

    2014-01-01

    Background Lead-free hunting bullets are an alternative to lead-containing bullets which cause health risks for humans and endangered scavenging raptors through lead ingestion. However, doubts concerning the effectiveness of lead-free hunting bullets hinder the wide-spread acceptance in the hunting and wildlife management community. Methods We performed terminal ballistic experiments under standardized conditions with ballistic soap as surrogate for game animal tissue to characterize dimensionally stable, partially fragmenting, and deforming lead-free bullets and one commonly used lead-containing bullet. The permanent cavities created in soap blocks are used as a measure for the potential wound damage. The soap blocks were imaged using computed tomography to assess the volume and shape of the cavity and the number of fragments. Shots were performed at different impact speeds, covering a realistic shooting range. Using 3D image segmentation, cavity volume, metal fragment count, deflection angle, and depth of maximum damage were determined. Shots were repeated to investigate the reproducibility of ballistic soap experiments. Results All bullets showed an increasing cavity volume with increasing deposited energy. The dimensionally stable and fragmenting lead-free bullets achieved a constant conversion ratio while the deforming copper and lead-containing bullets showed a ratio, which increases linearly with the total deposited energy. The lead-containing bullet created hundreds of fragments and significantly more fragments than the lead-free bullets. The deflection angle was significantly higher for the dimensionally stable bullet due to its tumbling behavior and was similarly low for the other bullets. The deforming bullets achieved higher reproducibility than the fragmenting and dimensionally stable bullets. Conclusion The deforming lead-free bullet closely resembled the deforming lead-containing bullet in terms of energy conversion, deflection angle, cavity shape, and reproducibility, showing that similar terminal ballistic behavior can be achieved. Furthermore, the volumetric image processing allowed superior analysis compared to methods that involve cutting of the soap blocks. PMID:25029572

  16. 2014 Mount Ontake eruption: characteristics of the phreatic eruption as inferred from aerial observations

    NASA Astrophysics Data System (ADS)

    Kaneko, Takayuki; Maeno, Fukashi; Nakada, Setsuya

    2016-05-01

    The sudden eruption of Mount Ontake on September 27, 2014, led to a tragedy that caused more than 60 fatalities including missing persons. In order to mitigate the potential risks posed by similar volcano-related disasters, it is vital to have a clear understanding of the activity status and progression of eruptions. Because the erupted material was largely disturbed while access was strictly prohibited for a month, we analyzed the aerial photographs taken on September 28. The results showed that there were three large vents in the bottom of the Jigokudani valley on September 28. The vent in the center was considered to have been the main vent involved in the eruption, and the vents on either side were considered to have been formed by non-explosive processes. The pyroclastic flows extended approximately 2.5 km along the valley at an average speed of 32 km/h. The absence of burned or fallen trees in this area indicated that the temperatures and destructive forces associated with the pyroclastic flow were both low. The distribution of ballistics was categorized into four zones based on the number of impact craters per unit area, and the furthest impact crater was located 950 m from the vents. Based on ballistic models, the maximum initial velocity of the ejecta was estimated to be 111 m/s. Just after the beginning of the eruption, very few ballistic ejecta had arrived at the summit, even though the eruption plume had risen above the summit, which suggested that a large amount of ballistic ejecta was expelled from the volcano several tens-of-seconds after the beginning of the eruption. This initial period was characterized by the escape of a vapor phase from the vents, which then caused the explosive eruption phase that generated large amounts of ballistic ejecta via sudden decompression of a hydrothermal reservoir.

  17. Combined Structural and Compositional Evolution of Planetary Rings Due to Micrometeoroid Impacts and Ballistic Transport

    NASA Technical Reports Server (NTRS)

    Estrada, Paul R.; Durisen, Richard H.; Cuzzi, Jeffrey N.; Morgan, Demitri A.

    2015-01-01

    We introduce improved numerical techniques for simulating the structural and compositional evolution of planetary rings due to micrometeoroid bombardment and subsequent ballistic transport of impact ejecta. Our current, robust code is capable of modeling structural changes and pollution transport simultaneously over long times on both local and global scales. In this paper, we describe the methodology based on the original structural code of Durisen et al. (1989, Icarus 80, 136-166) and on the pollution transport code of Cuzzi and Estrada (1998, Icarus 132, 1-35). We provide demonstrative simulations to compare with, and extend upon previous work, as well as examples of how ballistic transport can maintain the observed structure in Saturn's rings using available Cassini occultation optical depth data. In particular, we explicitly verify the claim that the inner B (and presumably A) ring edge can be maintained over long periods of time due to an ejecta distribution that is heavily biased in the prograde direction through a balance between the sharpening effects of ballistic transport and the broadening effects of viscosity. We also see that a "ramp"-like feature forms over time just inside that edge. However, it does not remain linear for the duration of the runs presented here unless a less steep ejecta velocity distribution is adopted. We also model the C ring plateaus and find that their outer edges can be maintained at their observed sharpness for long periods due to ballistic transport. We hypothesize that the addition of a significant component of a retrograde-biased ejecta distribution may help explain the linearity of the ramp and is probably essential for maintaining the sharpness of C ring plateau inner edges. This component would arise for the subset of micrometeoroid impacts which are destructive rather than merely cratering. Such a distribution will be introduced in future work.

  18. Combined structural and compositional evolution of planetary rings due to micrometeoroid impacts and ballistic transport

    NASA Astrophysics Data System (ADS)

    Estrada, Paul R.; Durisen, Richard H.; Cuzzi, Jeffrey N.; Morgan, Demitri A.

    2015-05-01

    We introduce improved numerical techniques for simulating the structural and compositional evolution of planetary rings due to micrometeoroid bombardment and subsequent ballistic transport of impact ejecta. Our current, robust code is capable of modeling structural changes and pollution transport simultaneously over long times on both local and global scales. In this paper, we describe the methodology based on the original structural code of Durisen et al. (Durisen, R.H. et al. [1989]. Icarus 80, 136-166) and on the pollution transport code of Cuzzi and Estrada (Cuzzi, J.N., Estrada, P.R. [1998]. Icarus 132, 1-35). We provide demonstrative simulations to compare with, and extend upon previous work, as well as examples of how ballistic transport can maintain the observed structure in Saturn's rings using available Cassini occultation optical depth data. In particular, we explicitly verify the claim that the inner B (and presumably A) ring edge can be maintained over long periods of time due to an ejecta distribution that is heavily biased in the prograde direction through a balance between the sharpening effects of ballistic transport and the broadening effects of viscosity. We also see that a "ramp"-like feature forms over time just inside that edge. However, it does not remain linear for the duration of the runs presented here unless a less steep ejecta velocity distribution is adopted. We also model the C ring plateaus and find that their outer edges can be maintained at their observed sharpness for long periods due to ballistic transport. We hypothesize that the addition of a significant component of a retrograde-biased ejecta distribution may help explain the linearity of the ramp and could provide a mechanism for maintaining the sharpness of C ring plateau inner edges. This component would arise for the subset of micrometeoroid impacts which are destructive rather than merely cratering. Such a distribution will be introduced in future work.

  19. Using Computer Simulations to Model Scoria Cone Growth

    NASA Astrophysics Data System (ADS)

    Bemis, K. G.; Mehta, R. D.

    2016-12-01

    Scoria cones form from the accumulation of scoria delivered by either bursting lava bubbles (Strombolian style eruptions) or the gas thrust of an eruption column (Hawaiian to sub-Plinian style eruption). In this study, we focus on connecting the distribution of scoria delivery to the eventual cone shape rather than the specifics of the mechanism of delivery. For simplicity, we choose to model ballistic paths, that follow the scoria from ejection from crater to landing on the surface and then avalanching down slope. The first stage corresponds to Strombolian-like bursts of the bubble. The second stage only occurs if the angle of repose is greater than 30 degrees. After this condition is met, the scoria particles grain flow downwards until a stable slope is formed. These two stages of the volcanic eruption repeat themselves in the number of phases. We hypothesize that the horizontal travel distance of the ballistic paths, and as a result the width of the volcano, is primarily dependent of the velocity of the particles bursting from the bubble in the crater. Other parameters that may affect the shape of cinder cones are air resistance on ballistic paths, ranges in particle size, ballistic ejection angles, and the total number of particles. Ejection velocity, ejection angle, particle size and air resistance control the delivery distribution of scoria; a similar distribution of scoria can be obtained by sedimentation from columns and the controlling parameters of such (gas thrust velocity, particle density, etc.) can be related to the ballistic delivery in terms of eruption energy and particle characteristics. We present a series of numerical experiments that test our hypotheses by varying different parameters one or more at a time in sets each designed to test a specific hypothesis. Volcano width increases as ejection velocity, ejection angle (measured from surface), or the total number of scoria particles increases. Ongoing investigations seek the controls on crater width.

  20. Ballistic Performance of Alimina/S-2 Glass-Reinforced Polymer-Matrix Composite Hybrid Lightweight Armor Against Armor Piercing (AP) and Non-AP Projectiles

    DTIC Science & Technology

    2007-01-01

    and a phenolic -resin based polymeric matrix. Such armor panels offer superior protection against fragmented ballistic threats when compared to...database does not contain a material model for the HJ1 composite but provides a model for a Kevlar Fiber Reinforced Polymer (KFRP) containing 53 vol... phenolic resin and epoxy yield stresses and then with a ratio of the S-2 glass and aramid fibers volume fractions. To test the validity of the

Some links on this page may take you to non-federal websites. Their policies may differ from this site.
Top