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Background: Ballistics deals with the study of projectile propulsion, flight, and impact in any medium. Different garment materials can have varying effects when it comes to the penetration of pellets into the body. Body armor has been around for a long time. Dhal, a curving strip of rhino hide, was possibly the first armor in India, used for sword fighting or defense against arrows and spears. It gave way to steel armor, which protected the body's essential organs from spear and arrow strikes. The current study is primarily concerned with how jeans material, when employed as body armor, contributes to the inquiry. The present study also examines how airgun pellets fired at various ranges affect jeans clothing wrapped around gel blocks. Results: The study concluded that when fired at varied ranges, there was no significant variation in the diameters of the entry holes on clothing material. The gel block covered with jeans clothing was not found to be more damaged. Conclusions: The findings also indicate that pellets had larger track lengths regardless of the range from which they were fired. [ABSTRACT FROM AUTHOR]

Traumatic injuries from civilian gunshot injuries represent a significant clinical burden to orthopaedic surgeons worldwide. Furthermore, the incidence of such injuries is increasing. Having a sound understanding of the pathophysiology associated with gunshot injuries and the appropriate management algorithm is vital. This chapter aims to review the current evidence regarding the incidence and prevalence of civilian ballistic trauma, the pathophysiological processes associated with these injuries, and the recommended management from emergent care at the time of injury to definitive surgery and rehabilitation. [ABSTRACT FROM AUTHOR]

This manuscript deals with life saving aspects of the pilot for escape aid explosive (EAX) system applications under emergency situation. During the ejection from the aircraft, the pilot is subjected to the various forces such as linear, angular and transverse accelerations, decelerations, wind drag accelerations, wind blast, dynamic forces, aerodynamic forces, spinning and tumbling. Linear accelerations (decelerations) of major interest in aviation are those of a high magnitude and a short duration that occur in emergency ejection from the aircraft or occasionally in a high altitude at high-speed parachute opening, as they tend to exceed the strength limitations of the skeletal structure of the pilot body. The human body is a heterogeneous mass that is made up of solid, liquid and visco elastic components. The effects of these forces on the pilot's body are crucial in nature and significant pertains to an injury. This article is described with some considerations of ballistics, kinematics with different forces and their effects on the pilot body for aircraft applications during an entire flight trajectory. In conclusion, this kind of study is very essential considering the pilots safety and its performance at low and high altitudes during an emergency. [ABSTRACT FROM AUTHOR]

The mortality rate from firearm injuries in the United States has decreased from 30.3 per 100,000 people in 1990 to 20.6 in 2010, likely because of improvement in treatments. However, the incidence of gunshot wounds continues to increase, including the number of mass shootings, even though the definition of which is still unclear. According to Gun Violence Archives, there were 346 mass shootings in the United States, defined as 4 or more injuries in a single incident, in 2017, with 437 deaths and 1803 injured. This article briefly reviews the ballistics of firearms pertinent for maxillofacial surgeons and summarizes the lessons learned from caring for patients with ballistic injuries to the craniofacial region based on the available peer-reviewed publications and the authors' combined experience of more than six decades. Specifically, we discuss in details the roles of plastic surgeons as a member of the multidisciplinary trauma team in the following three phases: damage control, definitive treatment, and long-term rehabilitation. [ABSTRACT FROM AUTHOR]

Background: In forensic ballistics, the phenomenon of tandem bullets occurs when two or more bullets are ejected from the barrel of a firearm in a single shot. The injuries caused by these bullets have been described in the literature and include several possibilities, whose severity seems to be especially related to the mass increase of the exploded cartridges and to the distance at which the shots are fired, as a result of the sudden drop in kinetic energy that occurs. Case presentation: We report the case of a subject hit by a tandem bullet, during an attempted robbery, describing the injury reported in relation to the ballistic analysis of the case and examining the dynamics in which this circumstance occurred. Conclusions: The ballistic analysis conducted in our case confirmed that the harmful potential of “tandem bullets” is inversely correlated to the mass of the fired bullets. In our case, the exploded shot, consisting of two 38 Special caliber bullets fused together, hit the body of the subject involved with minimal kinetic energy and penetrating potential. We believe that further ballistic studies should be conducted on a cadaveric model by exploiting cadaveric donation programs for scientific research purposes, in order to investigate the wide spectrum of possible injuries that can occur, also simulating the effects of unjacketed tandem bullets. [ABSTRACT FROM AUTHOR]

• Forensic casework often requires sieving through soil to search for human remains and other items. • The only soil search methods more commonly available are wet and dry sieving. • This study explored the use of X-ray baggage scanners to search for items in soil. • The baggage scanner provided a quick and easy way to detect items within soil. The need to forensically search soil for small artefacts at a burial site or traces of evidence in a deposition site is a common task shared by investigators and forensic archaeologists. In forensic casework, the importance of finding small pieces of evidence, such as personal effects or ballistic fragments, cannot be overstated as it can assist in the positive identification of the deceased, give an insight into the manner and cause of death, and identify any perpetrators. The soil search methods known as wet and dry sieving, are cumbersome, time-consuming and have limited success for some soil types. This often leads to the decision not to search, resulting in missed opportunities to identify potential evidence. The primary aim of this study was to investigate if a dual energy X-ray baggage scanner could be used to search for items of potential forensic interest in soil. A trial was conducted using a Smiths Detection ScanTrailer 100100 V-2is mobile X-ray inspection system to establish if it could be used to detect organic, inorganic, and metallic items located within soil. The soil type and natural variables such as water and organic content were adjusted to simulate different environments. The baggage scanner was found to provide a quick and easy way to detect items contained within various soil types, particularly in a sand rich matrix. It is estimated that using this method to search 1 m3 of soil, when broken down into samples that are < 13 cm in depth, would take around one hour to complete, compared with 100 to 150 person-hours by manual sieving. This is believed to be the first use of dual energy X-ray technology for this purpose and shows the potential for further research and use of this method in forensic archaeology. [ABSTRACT FROM AUTHOR]

• Fingermark enhancement processes deposit constituents on the target substrate. • Ammunition casings require ballistics examination to identify firing impressions. • The headstamp area of the casing is the most important area that needs preserving. • A polymer mask protects ammunition headstamp areas during fingermark processing. • The mask does not appear to leave a residue or interfere with fingermark/ballistic examinations. Forensic recovery from fired ammunition casings remains one of the most challenging tasks during high-profile investigations. Often, the decision must be made between screening for DNA or fingerprints, and, in doing so, the impact these processes will have on the examination of ballistic markings imparted on the ammunition from the firearm itself. Traditionally, fingermark enhancement processes have yielded low success rates in their efforts to identify suspects by enhancing friction ridge detail left on the cartridge casings. Moreover, the enhancement methods utilised may often induce detrimental physical changes to the casing(s), rendering them unsuitable for subsequent ballistics (marking) examination. Recently, new technology has been shown to increase the success rate of fingermark recovery from fired ammunition, and the growing adoption of such innovation means that new challenges are encountered to maximise evidence recovery and streamline forensic workflows. One such example arises from the potential obscuration of the ammunition headstamp area during such treatments. Accordingly, this study outlines the preliminary investigations and developments of a polymer mask substrate that serves to protect the headstamp of fired ammunition casings during relevant fingermark enhancement processes. The technique also has the capacity to be used as a surface protection device to eliminate unwanted chemical deposition across other areas of interest and evidence types. [ABSTRACT FROM AUTHOR]

Understanding the heat transfer phenomenon during interior ballistics and consequently presenting a realistic model is very important to predict the temperature distribution inside the cannon barrel, which influences the gun wear and the cook-off. The objective of this work is to present a new detailed numerical model for the prediction of thermal behaviour of a cannon barrel by combining PRODAS interior ballistics simulation with COMSOL simulation. In this study, a numerical model has been proposed for the heating behaviour of a 120 mm smoothbore cannon barrel, taking into account the combustion equation of the JA-2 propellant. Temperature dependent thermophysical properties of product gases were used for the calculation of the convective heat transfer coefficient inside the barrel. Projectile position, velocity of the projectile, gas temperature inside the barrel, volume behind the projectile and mass fraction during interior ballistics have been obtained by PRODAS software and used in the numerical model performed by COMSOL multiphysics finite element modelling and simulation software. Temperature simulations show that maximum wall temperature inside the cannon barrel is observed after 3 ms from fire, when maximum value of the convective heat transfer coefficient inside the barrel is observed. The results reveal that the convective heat transfer coefficient of burned gases inside the gun has major effect than the burned gas temperature on the heat transfer phenomenon. [ABSTRACT FROM AUTHOR]

In this work, the finite element software (ABAQUS) was used to build a single-cell model based on three-dimensional woven reinforced composite and investigate the propagation of stress waves in the composite. The experimental results of the edge part of the bullet after impact with the results of simulations were compared, and the final damage pattern of three-dimensional woven reinforced composite with commonly used laminates were also comparatively studied. The results indicated that the peak stress of the bullet in the three-dimensional woven reinforced composite increased with increasing incident velocity and was reflected back and forth. The fracture of the reinforcement yarn was rougher after the bullet was ejected from the lower surface of the three-dimensional woven reinforced composite than from the incident upper surface. Delamination did not occur within the three-dimensional woven reinforced composite, and the observed damage holes were generally consistent with the graphs simulated using finite element software. The research in this paper provides a design method for the application of three-dimensional orthogonal hybrid woven reinforced composites in ballistic protection. The experimental results and corresponding calculation methods can guide the design of high-performance protective armor. [ABSTRACT FROM AUTHOR]

A chronological synopsis of the history of the technology used in experimental and testing work relating to artillery pieces is presented. The period covered is from the mid-seventeenth century up to the Cold War era of the mid-twentieth century. Although the focus is on the development of ballistics measurement in Britain, there are important links to related work in continental Europe. The locus for much of what is described is the Royal Artillery proof and experimental range at Shoeburyness and the key individuals and groups of men and women who worked there. There are longitudinal connections between the very earliest technologies of mechanical chronometry, with paper screens and paper-based calculations, and the later technology where timings, screens and calculations had all become electronic. [ABSTRACT FROM AUTHOR]

This paper deal with the comparison of relative wounding potential of guns, which we know from childhood, specifically blowpipe and slingshot. Many people played with these guns in childhood without knowing how dangerous these guns are. Because this area has not been examined enough, this paper focuses on it. The relative wounding potential is examined through an experimental method. This method is indirect and includes shooting to the replacement material, which was gelatine with a concentration of 20 %. Using a high-speed camera, the course of missiles in the target, from penetration to stopping, is recorded. The volume of the temporary cavity is determined by image analysis, and subsequently, the relative wounding potential is calculated. Other monitored parameters are the depth of penetration of the projectile and the impact velocity of the projectile. Then, it is possible to determine the transmitted kinetic energy of the projectile. The results should help to assess the dangers of these "children's" weapons and alert society to their risks. They can also serve to experts in the field of ballistics and forensic expertise. [ABSTRACT FROM AUTHOR]

• Ballistic tramatology in the upper humerus extremity region presents challenging management difficulties. • Resurfacing shoulder hemi arthroplasty in ballistic injuries is not commonly reported. • The indication of resurfacing shoulder hemi arthroplasty was appropriate regarding good functional outcome. Ballistic traumatology of the shoulder joint is uncommon. Usually, it is associated to comminuted fractures of the upper humerus. Total shoulder arthroplasty has been proposed to restore a good function. The indication of resurfacing hemi arthroplasty still controversial and is not commonly reported after ballistic traumatology. We report the case of a 26-year-old soldier victim of a gunshot of the left shoulder entailing a comminuted complex fracture of the upper extremity of the humerus. After shoulder immobilization of 3 months joint mobility was very limited. Radiographs showed bone malunion with a total loss of the hemispherical form of the humeral head. Patient has undergone a resurfacing hemi arthroplasty. Surgery outcome was good. At five years of follow-up, there were no major functional complaints. Clinical and radiological result was satisfactory with a good shoulder mobility. Shoulder arthroplasty provided good functional outcome in case of post fracture sequelae. Difficulty was to choose between total arthroplasty and hemi arthroplasty. In young and active patients, authors disapproved total arthroplasty in post traumatic gleno-humeral arthrosis to prevent revision difficulties especially after glenoid erosion. Although follow-up still be limited, the indication of shoulder hemi arthroplasty was appropriate regarding functional outcome and patient satisfaction. Further clinical and radiological supervision still necessary to detect glenoid erosion. [ABSTRACT FROM AUTHOR]

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 4.8 mm steel ball penetrating the 60 kg porcine hind limbs and 10 wt% 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. [ABSTRACT FROM AUTHOR]

Protective shields are used to protect the technical devices from the impacts of high-speed objects, for example, the space systems from orbital garbage. This problem is so important that special spacecrafts are designed to clean up the trash. Ceramic-polymer composite panels have some advantages. However, the characteristics of such panel components have not been studied sufficiently yet. The finite element analysis is an efficient method for the composite characteristics improvement. Obviously, such improvement necessitates searching for a rich variety of composites characteristic. Each option requires creating a brick elements mesh. Adequate FE models have to be developed for penetrators (metal cones, for example) as well as for panels. Voxel based micro modeling makes it possible to develop a composite structure parametrical model. Further on, it is easy to transform this model to FE one. Developing a material model is an important problem of the impact simulation. To study the ceramic-polymer composite behavior using a traditional Johnson-Holmquist model and the most recent Toughened Adhesive Polymer model is suggested. The calculations using LS-DYNA give initial adequate results for impact modeling and thus the suggested approaches of geometrical and of FE modeling are rather effective. [ABSTRACT FROM AUTHOR]

One of the primary design considerations of earth-orbiting spacecraft is the mitigation of the damage that might occur from an on-orbit MMOD impact. Traditional damage-resistant design consists of a ‘bumper’ that is placed a small distance away from a spacecraft component or from the wall of the element in which it is housed. The performance of such a multi-wall structural element is typically characterized by its ballistic limit equation (BLE), which defines the threshold particle size that results in a failure of the spacecraft element. BLEs are also key components of any micro-meteoroid/orbital debris (MMOD) risk assessment calculations. However, these assessments often call for BLEs to predict impact response for projectiles made of materials not used in the development of those BLEs. The question naturally arises regarding how close are the predictions of such BLEs when used in impact scenarios involving projectiles made of materials not necessarily considered in their development. In an effort to address this issue, a study was performed with the objective of assessing the validity of the NNO BLE for non-aluminum particles. Particle materials considered included steel, copper, and Al 2 O 3 (i.e. particles that are made of materials that are more dense than aluminum). Comparisons are made between actual test results involving these non-aluminum projectiles and the predictions of the NNO BLE. In nearly all cases, the NNO BLE was found not to work very well in the predicting failure / no failure response of these non-aluminum projectiles. A new NNO-type BLE is then developed that can be used to more reliably predict the response of dual-wall systems under the hypervelocity impact of such “heavier” non-aluminum projectiles. [ABSTRACT FROM AUTHOR]

Ballistic maxillofacial trauma in the UK is fortunately relatively rare, and generally involves low velocity handguns and shotguns. Civilian terrorist events have, however, shown that all maxillofacial surgeons need to understand how to treat injuries from improvised explosive devices. Maxillofacial surgeons in the UK have also been responsible for the management of soldiers evacuated from Iraq and Afghanistan, and in this review we describe the newer types of treatment that have evolved from these conflicts, particularly that of damage-control maxillofacial surgery. [ABSTRACT FROM AUTHOR]

Cold Metal Transfer (CMT) is a proven type of welding method using Metal Inert Gas (MIG). It is a welding technique which can be employed for marine fabrications too. Plates of AA5086-H111 and AA6061-T6 with AA4043 filler is welded by CMT. Parameters like current, voltage, arc length, shield gas pressure etc. are varied to obtain a continuous weld without any crack. Welded thin plates are subjected to a tensile test as per American Welding Society (AWS B4.0:2007) and thereafter impact loads are applied. The plates subjected to impact loads in the range of sub-ordinance level velocities, the feasibility of ordinance and ultra-ordinance can be scaled and compared. Responses and terminal ballistics limit are determined for plate thickness of 1.2 mm and 3 mm. Present work consists of simulation using Abaqus Software and experiments using Laboratory prepared gun. It was observed that, there was petaling in very thin plates and in some plates it was perforated by plugging for lower ballistic loads and thinner plates. The work gives new insights into the application of CMT in joining plates of different materials with varied thickness values. The material property of plates joined by this welding method was found to be new resource information to the permanent literature of material technology. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ballistic optimization of the L1-L2 and L2-L1 missions in the Earth-Moon system using electric propulsion is considered. The motion control is studied using the Fedorenko's successful linearization method to estimate the derivatives and the gradient method to optimize the control laws. The transfers are designed in frames of the restricted circular three-body problem. The mathematical model of the missions is described within the barycentric system of coordinates. The perturbation from the Earth, the Moon and the Sun are taking into account. The impact factor of the shaded areas, produced by the Earth and the Moon, is also accounted for. As for the results, the optimization of the optimal control laws and corresponding trajectories were obtained. [ABSTRACT FROM AUTHOR]

The problem of the choice of optimal ballistic schemes for a transfer to a geostationary orbit (GEO) with low and high thrust propulsion is considered. A bi-criteria optimization problem is solved by outputting a set of Pareto-optimal solutions. Results of the numerical modeling of combined insertion schemes, their ballistic optimization, and calculations of design parameters for a spacecraft with a combined propulsion unit are given. To insert a satellite into a given orbital plane, semi-major axis and eccentricity deviations are reduced by solving a terminal control problem. An approximately-optimal control and an expression for characteristic velocity expense as a function of initial boundary conditions with insertion of an electric propulsion (EP) powered spacecraft into a given station with the control are obtained. [ABSTRACT FROM AUTHOR]

Energy absorption behavior of flexible armour materials treated with Shear Thickening Fluids (STF) was studied. Five different structures were prepared with varying thread densities of p-aramid yarns, followed by treatment with 60% w/w STF. In untreated condition, plain woven fabrics show highest impact resistance in low velocity impacts, followed by 3/1 twill, 2/2 twill, 5-end satin and 2/2 matt weaves. Ballistic impact mitigation behavior improves with increase in thread density in case of plain woven fabrics. Addition of STF significantly improves both low and high velocity impact behavior of the panels. Low velocity behavior of STF treated fabrics have been published previously [12]. This paper brings together both low and high velocity impact behavior of various geometries of fabrics. It was seen that both primary and secondary yarns are engaged during impact which improves impact mitigation behavior of STF treated fabrics. However, fabrics get jammed at thread densities beyond 32×32 per inch. As was observed earlier in low velocity impact conditions, addition of STF did not enhance performance of fabrics with high thread density in high velocity impact as well. [ABSTRACT FROM AUTHOR]

Effect of heat treatment on mechanical properties and ballistic resistance of AA-7017 aluminium alloy plates has been investigated. The stress-strain behaviour of AA-7017 plates subjected to different heat treatment schedules namely under-aging, peak aging and over-aging, is evaluated from quasi-static tension tests. The heat-treated plates display large differences in static mechanical properties in terms of strength and ductility. The peak-aged plate shows the highest strength and hardness followed by the under-aged and over-aged materials. The ballistic resistance of these plates are evaluated by impacting deformable projectiles at a velocity of 830±10 m/s at a normal angle of attack. The peak-aged plate exhibits the best ballistic penetration resistance. The changes in the mechanical properties with different heat treatments have been correlated with ballistic performance of the AA-7017 alloy. Both the post ballistic micro-structural observations and micro-hardness measurements adjacent to the impacted crater walls have been carried out to understand the change in material deformation behaviour with heat treatment. [ABSTRACT FROM AUTHOR]

Numerical investigations were carried out on 1.27, 3.18, 6.35, 12.7and 19.05 mm thick 2024-O aluminum target against blunt nose steel projectiles of 12.7 mm diameter and 37.7 gram mass. Three-dimensional numerical simulations of the problem are carried out using finite element code ABAQUS. The ABAQUS/Explicit finite element code in conjunction with Johnson-Cook elasto-viscoplastic material model proposed by Leuser[1] was employed to perform the simulations. The present studyis concerned with the measurement of ballistic limit of deformable projectiles. The results obtained were compared with the experimental results conducted by [3,4] and a close correlation between the two was found. The failure mode of the target was also found in good agreement. The results obtained showed a consistent increase in the ballistic resistance of target with an increase in the target thickness. [ABSTRACT FROM AUTHOR]

Steel containing 0.65 wt % nitrogen has been investigated for armour applications by subjecting it to different percentages of hot rolling. The effect of percentage reduction during hot rolling on microstructures, mechanical properties and ballistic performance has been studied. The ballistic performance of 6.5 mm, 7.5 mm thick plates against 7.62 ball and 16 mm, 17 mm thickness against 7.62AP projectiles were assessed. The nature of damage has been studied by varying percentage reduction during hot rolling of these plates for providing full protection. [ABSTRACT FROM AUTHOR]

The ballistic resistance of 12 mm thick mild steel plates has been studied against 7.62 API projectiles through numerical simulations carried out using ABAQUS/Explicit finite element code. The incidence angle was varied as 0°, 15°, 30°, 45°, 57° and 59°. The material parameters for the JC model proposed by the Authors were employed to predict the material behavior of the target, while the material behavior of the projectile was incorporated from the available literature. The numerical results thus obtained have been compared with the experiments reported in earlier study, wherein the incidence velocities of the projectile were considered close to 820 m/s. The experimental and numerical results with respect to failure mechanism, residual projectile velocity and critical angle of ricochet have been compared. A close correlation between the experimental findings and the predicted results has been found. In general, the resistance of the target has been found to increase with increase in target obliquity. [ABSTRACT FROM AUTHOR]

In this study, bubbled- armour forms are assessed for ballistic penetration resistance. A key component is optimization of the bubble shape to maximize its fundamental modal frequency. A ‘large- plastic- regime’ automotive steel alloy is adopted for the bubble and the penetration process simulated by LS- DYNA for a ‘rigid’ projectile. Three forms: - a flat-, spherical and the shape- optimized one, of identical planform dimensions and mass, are studied for their penetration resistance characteristics under a common impact speed. The optimum form is found to be the most superior, causing a momentum loss of as much as 140%, implying a total reversal of the projectile, post- impact. This is more than the 111% for the spherical form and far above the 30% for the flat form. Modal response also correlates well with impact- induced bubble- response acceleration in wavelet decomposition. We conclude that with the fundamental modal frequency maximized, shape- optimized bubbled- armour forms can have much higher penetration resistance than a traditional plate armour's. [ABSTRACT FROM AUTHOR]

Conical aluminium projectiles of apex angle 34 degrees were made to impact thin aluminium targets inclined at an angle of 60 degrees at low subordnance velocities where material strength effects are still valid. Thin targets of thickness 1.5 mm and 2 mm underwent failure by reverse petalling as the projectiles penetrated the targets. Projectiles underwent ricochet while impacting 2.5 mm targets causing severe dents and visible contact marks on the target. While the projectile nose tips were separated in the 1.5 mm and 2 mm cases, the projectiles impacting 2.5 mm targets underwent substantial nose deformation. Numerical simulation performed using ABAQUS/Explicit was able to capture the projectile deformation and target deformation quite well phenomenologically. [ABSTRACT FROM AUTHOR]

The suitability of agar/glycerol/water and agar/glycerol mixtures as brain simulants was investigated. Test specimens (n=15) (50x27×37mm) were fabricated for these different mixtures and conditioned to 12 °C, 22 °C, and 26 °C prior to testing. For comparison, fresh deer brain specimens (n=20) were sourced and prepared to the same dimensions as the agar/glycerol(/water) mixtures and conditioned to 12 °C and 37 °C. High impact tests were carried out with a 0.22-caliber air rifle pellet and a high-speed camera was used to record the projectile as it passed through the specimens, allowing for energy loss and vertical displacement velocity calculation. Although the agar/glycerol/water mixture presented with similar vertical expansion and contraction of the specimens to the warm and cold deer brains, a two-fold decrease of the vertical expansion and contraction was noticed with the agar/glycerol specimens. Also considerably less extrusion of this mixture out of the exit and entry sides after specimen penetration was observed. Of the simulants tested, agar/glycerol/water was the most suitable brain simulant for ballistic testing and impact studies. [ABSTRACT FROM AUTHOR]

For the first time, a classification system for organic gunshot residue (OGSR) compounds with respect to the confirmation of OGSR materials is presented. There are 136 compounds considered to be associated with OGSR that have been highlighted in the literature. Many of these compounds could be classified as being ubiquitous in the environment and thus their detection as characteristic components of OGSR could cause issues with the interpretation of chemical ballistic evidence. The proposed system aims to address this problem by classifying OGSR compounds based on their forensic relevance with respect to the confirmation of GSR materials. To increase the forensic relevance of such a system, the large number of OGSR compounds reported in the literature has been decreased to 20 OGSR compounds based on the organic chemical composition of over 200 propellant powders. Occupational and environmental materials also associated with OGSR compounds have been considered. [ABSTRACT FROM AUTHOR]

We report a case of a Tunisian footballer who was found dead abroad under suspicious circumstances. The cause of death was, originally, attributed to a lightning strike. The corpse was buried without/autopsy. Over thirty years later, the family requested the exhumation to verify the identity and the cause of death. The exhumation was performed in 2011. DNA profiling from teeth and femur bone samples confirmed the identity of the deceased. The dry bone study revealed defects in the skull and the pelvis evoking firearm injuries. Post-mortem CT with three-dimensional (3-D) reconstruction allowed to confirm the characteristics of firearms injuries and to speculate about the number and the trajectories of potential shots. Nevertheless, the vitality of these injuries as well as the eventual fatal shot and the shooting distance could not be determined. Likewise, the type of the eventual weapon could not be clarified as there were no bullets or any metallic projectile fragments. Despite all doubts, the forensic explorations have allowed to verify the identity of the deceased, to evoke firearms injuries and, mainly, to deny the proposed cause of death after more than thirty years of burial. Moreover, the loss of soft tissues and bone fragility were the major obstacles. [ABSTRACT FROM AUTHOR]

Error analysis of spin measurement using synchro-ballistic method is presented in this paper. Error in the spin measurement varies as the projections of marker move away from axis of symmetry, and the reason for variation of error is explained. An improvement to synchro-ballistic method is proposed for spin measurement, which reduces the error in measured spin, and an algorithm for implementation of same is provided. Results of improved synchroballistic method are compared with the theoretical estimation of spin from muzzle velocity. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the terminal ballistics of police shootings in which the bullets went through any motor vehicle structure before fatally wounding the occupants. 6 cases that occurred in Porto district between 1998 and 2013 were studied. The firearms used were 7.65 mm (n = 1) or 9 mm (n = 3) calibre semi-automatic pistols and 9 mm calibre submachine guns (n = 2); the bullets were full metal jacket type. The metal jacket of the collected projectiles was totally or partially destroyed in 3 cases. It exhibited a deformed structure in all cases. The trajectories of the bullets in the vehicles were always more or less linear, even when initial impact was at an oblique angle. The entry holes in the victims' bodies were larger or much larger in size than the calibre of the bullets. They were located, with the exception of one of the cases, in the left half of the body. The trajectories in the victims' bodies were from front to back, in one case, and from back to front in all others. Exit wounds were only found in two cases. Death occurred immediately after the victim was shot only in one case, despite a vital structure has been hit in all cases. The cases studied support the idea that the use of firearms against vehicles with the sole intention of immobilisation entails uncontrollable danger to the lives of the occupants, and especially when done by police forces not specifically trained for that purpose. Therefore, such use of firearms should be avoided. [ABSTRACT FROM AUTHOR]

Drag coefficient is an important parameter in exterior ballistic which is used to evaluate the shape of projectile trajectory. The purpose of this study was to create a simple instrument for drag coefficient preliminary evaluation using the existing drag laws: 1943 law, 1930 law or Siaccis's law and his geometrical dimensions important for ballistics. The instrument mentioned before is represented by a software module which is based on an existing theoretical model, properly ajusted, for drag coefficient evaluation. This software module has the ability to evaluate also the influences for some geometrical dimension tolerances of projectile's shape against drag coefficient. [ABSTRACT FROM AUTHOR]

Copyright of Llull: Revista de la Sociedad Espanola de Historia de las Ciencias y de las Tecnicas is the property of Sociedad Espanola de Historia de las Ciencias y de las Tecnicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Authors study ballistic properties of the material which has never been used for impact protection and the presented results prove that synthetic mineral alloys belong to the field of bulletproof ballistic protection and particularly to the means of objects' protection from kinetic threats. Although the material has been described in connection with such specific embodiments as SVD and a cumulative jet, it is evident that many alternatives and modifications of their application for various protective articles are possible. [ABSTRACT FROM AUTHOR]

The article discusses a study that developed a longitudinal dynamic model of an aircraft with gravity extracted packages to estimate optimal aerial release points for improving high-altitude ballistic airdrop precision. Lagrangian methods were used to provide accurate estimates of initial conditions for a three-degree of freedom (3-DOF) parachute descent model. Optimization of individual discrete control events was used to reduce impact dispersion.

The objective of this study is to investigate the effect of multi walled carbon nanotube (MWCNT) inclusion on the fracture toughness and the ballistic resistance properties in terms of energy absorption. The determination of fracture toughness of the epoxy/MWCNT matrix was carried out by using a single edge notch bending (SENB) method according to the ASTM D5045-99. Four different weight percentage (wt %) of multi-walled carbon nanotubes (MWCNTs) contents were used, which were 0 wt.%, 0.1 wt.%, 0.55 wt.% and 1.0 wt.%. Epoxy binder and MWCNTs were mixed by using a mechanical stirrer for 10 minutes at 1500 rpm speed and was further sonicated for 30 minutes at 30 Hz amplitude in order to enhance the homogeneity of MWCNTs in the matrix. The compositepanel comprised of Twaron fabrics with epoxy resin filled with MWCNTs was fabricated using hand layup and vacuum bagging assist method. The Twaron/epoxy/MWCNT composite panels weresubjected toa ballistic test using 9 mm Full Metal Jacket bullet at different impacting velocities. From the SENB results, it can be reported that MWCNT inclusion up to 1.0% w.t content shows significantinfluence towards increment of fracture toughness value.MWCNT also improves the ballistic resistance capability of the composite panel where it was found that the impact energy absorption value was proportionally increasewith theepoxy/MWCNT matrix's fracture toughness properties. [ABSTRACT FROM AUTHOR]

This paper intends to develop a target trajectory estimation algorithm with application to the ballistic target estimation in the terminal phase. The proposed design is based on the application of a second-order extended state observer (ESO) technique using target information acquired from the seeker to estimate the trajectory of manoeuverable ballistic targets. Satisfactory results have been received while applying the design in estimation of either two-dimenional or threedimentional target evasive acceleration via computer simulation. [ABSTRACT FROM AUTHOR]

In the search of a new weapon for combat in short range, it is proposed the use of a new experimentally designed 7.62 mm calibre ammunition with a lighter weight (caseless-coreless). This can be used in carbine assault rifles with short barrel or pistols. In this work, the compressible gases flowing through the gun barrel caused by the proposed ammunition were experimentally and numerically analysed. The Large Eddy Simulation was used for the numerical simulation, considering a compressible and turbulent flow, with the chemical species transport model and a complete conversion of the propellant reaction. Variations in pressure and temperature were compared with the results obtained from a conventional 7.62 mm full metal jacket (FMJ) ammunition. Results of ballistic experimental tests and numerical simulations were similar than those of the 9 mm x 19 mm FMJ ammunitions, showing feasibility for the development of new weapons intended for operations of short range shots. [ABSTRACT FROM AUTHOR]

A computer code has been developed for internal ballistic performance evaluation of solid rocket motors, using minimum distance function (MDF) approach for prediction of geometry evolution. This method can handle any complex geometry without the need to define different geometrical shapes and their evolution as used in several existing analytical geometry evolution-based methodologies. The code is validated with both experimental results published in literature, as well as for solid rocket motors of tactical and strategic missiles and a very good match is obtained with static test results. The output of the code gives pressure-time (p-t) curve as well as the detailed parameters of the flow along the axial direction, and geometries in the form of mesh file, which can be further used as input to codes for CFD analysis. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Closed vessel firing of gun propellant at different loading densities is conducted for evaluation of its ballistic parameters. Although in actual gun applications, loading densities are higher, but for closed vessel evaluation standard loading density is taken as 0.2 g/cc for interior ballistic calculations of guns. Closed vessel evaluation of standard triple-base propellant in hepta-tubular configuration with loading density varying in the range of 0.2 g/cc to 0.3 g/cc is conducted for the evaluation of salient ballistic parameters. It is observed that maximum pressure increases with increase in loading density of propellants. As loading density increases, rate of rise of pressure also increases. Accordingly, a rise in burning rate is also observed. However, the burning rate index (α) and coefficient (β) of the power law of burning (r = βPα) is found independent of loading density. The average values of these burning rate parameters are calculated as (α =) 0.78 and (β =) 0.45 for the studied propellant. [ABSTRACT FROM AUTHOR]

The closed-form analytical solution to the equations of motion for ballistic entry developed by Allen and Eggers is presented using modern nomenclature and is extended and enhanced through several new developments. A method of choosing an appropriate constant flight-path angle is identified. Analytical limits are proposed that bound the domain of applicability of the approximation. Closed-form expressions for range and time are developed that are consistent with the assumptions in the Allen-Eggers approximation. Collectively, the improvements address key weaknesses in the original approximate solution. Assessment of the accuracy of the approximate solution relative to the planar equations of motion shows that the extended and enhanced Allen-Eggers solution provides good accuracy across a wide range of ballistic coefficients at Earth with initial flight-path angles steeper than about -7 deg. In some instances, the expression developed for range-to-go may be accurate enough for use in onboard real-time guidance and targeting systems. [ABSTRACT FROM AUTHOR]

The asymmetric radial crack patterns that occur in brittle targets when impacted by high velocity projectiles are explained using a Phenomenological Mechanochemistry of Damage (PMD) engineering model. The developed model, which constitutes a simplification of the generalized PMD framework, reveals an energy instability during failure of brittle materials configured in a purely symmetric geometry and impact configuration. The underlying cause of the instability is due to the competition between stored elastic energy and the energy associated with new surface creation through broken chemical bonds. The instability manifests itself in the form of asymmetric radial cracking in the brittle target. The model is built upon the general PMD framework and assumes the target material is sufficiently brittle that strains are small and linear elasticity is applicable. Furthermore, the impact geometry is assumed to be purely symmetric, which leads to a reduction of the geometry to a one-dimensional radial configuration. The model is not restricted to any ballistic impact speed regime, provided the target material remains in the solid phase. [ABSTRACT FROM AUTHOR]

The article presents the problem of protection against 5.7 x 28 mm SS190 projectiles with increased penetration capabilities. Due to the hybrid structure of the projectile, SS190 ammunition is a considerable danger to traditional, commonly used bulletproof vests based only on soft textile materials. A composite ballistic armour system based on small-size ceramics and fibre composites is presented as an answer to this threat. The construction of modern armour systems, the materials used and sample preparation is described. Ballistic test results of composite samples are presented by X-ray photographs. The authors also propose the possible use of these composite armour systems in personal body armour. [ABSTRACT FROM AUTHOR]