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Bats colliding with spinning wind turbine blades result in bat mortality. Carcass surveys at individual wind turbines vary from daily to once a week and from large cleared plots to only the road and pad area. A physics‐based model is proposed to guide carcass surveys, for designing curtailment studies to detect treatment fatalities and for improving fatality estimates by accounting for unsearched areas. The model considers the effects of carcass size, weight, and drag, and it accounts for the turbine rotor size and rotation rate to simulate the trajectory of a carcass after it is struck by a wind turbine blade. A carcass parameter is defined as the ratio of drag force to body weight, which accounts for the relative effect of bat biophysical and aerodynamic characteristics. By applying restrictions on carcass survey and turbine yaw data, a limited sample of bat fatalities was obtained, and the analysis revealed that bats fall downwind of wind turbines, indicating wind drift significantly influences carcass fall trajectories. The new ballistics model includes the effect of wind drift on fall trajectory of a carcass. The model was used to investigate the sensitivity of carcass fall trajectories to variability of the input parameters. The tests showed that larger values of the carcass parameter, that is, when drag dominates, such as for small carcasses, resulted in larger downwind drift, whereas large carcasses with smaller carcass parameter values resulted in larger distances within the rotor plane. The relationship of wind speed and RPM was found to influence the carcass downwind distance more compared to the within rotor plane distance. Using carcass survey data, turbine operation data, and wind speed records, for seven bats surveyed the day after colliding with a wind turbine, modelled back‐trajectories were used to identify the likely strike location on the rotor. The model can be improved by validating the modelled trajectories with the recorded bat‐blade strikes in thermal videos. It should be noted that the findings of the present study are based on the bat fatalities that met strict criteria leading to small sample size and hence requires further evaluation for testing the robustness of the model.

Because of its excellent insulation capability, the usage of a silica-phenolic charring ablator as a nozzle liner is a common practice in the solid rocket motor industry. During the design of a solid rocket motor employing a silica-phenolic nozzle liner, it is desired to conduct an accurate analysis yielding in-depth thermal response and recession characteristics. As the interior ballistics and nozzle recession rate mutually interact, the best practice is to perform a coupled solution to both. Commonly used one-dimensional analysis tools with empirical approaches for estimation of convective heat transfer rate and blowing effect generally lack sought accuracy and do not model the transient shape-change phenomenon, which affects the nozzle performance. This Paper considers governing equations for charring, including pyrolysis gas injection and surface energy balance for melting ablation, along with a boundary condition governed by interior ballistics, and demonstrates a framework in which these equations are solved with governing equations for the nozzle flowfield in a coupled manner. Development and validation of a one-dimensional material response solver based on the same governing equations is also demonstrated. Also, results from a static firing test conducted with a small-scale ballistic evaluation motor employing a silica-phenolic nozzle insert are provided. Results from both investigations are compared and discussed.

Supersonic accelerators use sabots to suppress bore balloting. However, sabot separation induces flight deviation in projectiles owing to their interactions with fluids and shock waves. A seamless ...

Purpose. The article analyzes assessment methods of existing fire extinguishing agent (FEA) jet ballistics. FEA discharge velocity from the nozzle effect on FEA drops in the air motion and trajectory has been investigated. Applying a new method for calculating FEA jets ballistics has been grounded. With the help of mathematical modeling, calculations have been carried out for FEA flow rate indicators depending on the pressure and flow rate for a universal nozzle, which forms different jet discharge angles from solid to spray. A model has been developed that describes FEA jet ballistics for both universal and conical or conoid fire nozzles. Methods. A logical method based on forces influence on a water drop in a medium has been used, as well as an empirical method, i.e. experiment. Findings. To confirm the developed jet ballistics theory, a series of field tests has been carried out. A fire monitor with a universal nozzle has been used as a test unit under the following conditions: equivalent diameter 29 mm; pressure in front of the nozzle 0.6 MPa; flow rate at the outlet 35 m/s (calculated by numerical simulation); nozzle inclination angle in relation to horizon 30°; nozzle cutting height from the horizon 1 m. The discrepancy in the indices of calculated and experimental jet range did not exceed 3 %. An insignificant effect of medium density change on jet range capability has been revealed, that is, under the same initial conditions, but at different ambient temperatures, fire extinguishing agent jet range capability will differ. This should be taken into account when using fire extinguishing installations based on monitors in different climatic regions. Research application field. The research results will simplify nozzle fire equipment development and design process, algorithm construction for robotic fire extinguishing installations operation based on fire monitors. Conclusions. The developed method for calculating jet ballistics is fully correlated with in-situ indicators. Jet ballistics is highly effected by fire extinguishing agents nozzle discharge velocity and medium density in which the fire extinguishing agent is flowing. In the future, it is required to conduct a number of scientific studies to determine extinguishing agent discharge velocity from various nozzles dependences on pressure and consumption.

The software for support of external ballistics calculation for weapons of 7.62 mm caliber is described taking into account external factors for the optical-electronic tactical exercise machine for small arms "Inhibitor" developed at the Institute of Mechanics UdmFRC UB RAS and at Computer facilities department of Kalashnikov ISTU jointly with JSC «Kalashnikov» Concern». A tactical and technical task is given for ballistic calculation of the trajectory up to 2 km of range of weapon simulators with a laser emitter of the targeting point taking into account external factors: types of sights, especially optical, ballistic scattering of bullets, deflection of the bullet from the side wind and derivation, which have a significant impact on the ballistic trajectory. The implemented differential mathematical model of external ballistics relying on the aiming angle of the weapon simulator depending on the sight readings, the initial speed and ballistic coefficient of various types of ammunition in real time builds a ballistic trajectory with adjustments for the air temperature and pressure and dependence on lateral wind and random dispersion of bullets to further solve the "problem of meeting" with obstacles. The given results of software tests for the error in calculating the coordinates of the ballistic trajectory showed full compliance with the requirements and adequacy of mathematical models. It was concluded that further research and development of electronic shooting simulators were promising thanks to the improvement of computing tools and the development of software libraries in order to increase the accuracy of simulating external ballistics of simulators taking into account many external factors, expand functional networks and reduce cost and, therefore, increase competitiveness.

In our previous work, we developed a new terminal-ballistics model developed for artillery high explosive projectiles with natural fragmentation. Lethal radius is here defined as the distance from the detonation point where the effective fragment (80 J) density is 1 frag/m2. In the model, the vertical position of the projectile upon impact is assumed, which means that the lethal radius defines a circular lethal zone (maximum lethal zone of the projectile on the ground). In the research, presented in this paper, we have applied the model to mortar projectiles and rocket warheads, which have different designs compared with classic artillery projectiles. The results from the model, compared to the available experimental results from the quarter-circular arena (used in our country), showed satisfactory accuracy for these types of munitions.

In this research, there was considered a challenge of constructing a system of scientific knowledge of the shot conditions in judicial ballistics. It was observed that there are underlying factors that are intended to ensureits [scientific knowledge] consistency: identification of the list of shot conditions, which require consideration when solving expert-level research tasks on weapons, cartridges and traces of their action; determination of the communication systems in the course of objects’ interaction, which present the result of exposure to the conditions of the shot; classification of the shot conditions based on the grounds significant for solving scientific and practical problems. The article contains the characteristics of a constructive, functional factor (condition) of weapons and cartridges influence, environmental and fire factors, the structure of the target and its physical properties, situational and spatial factors, and projectile energy characteristics. Highlighted are the forms of connections formed in the course of objects’ interaction, proposed are the author’s classifications of forensically significant shooting conditions with them being divided on the basis of the following criteria: production from the object of interaction, production from a natural phenomenon, production method, results weapon operation and utilization, duration of exposure, type of structural connections between interaction objects, number of conditions that apply when firing and the forming traces.

At this time, a scientific approach has developed in ballistics, in which the topic of the conditions of the shot is addressed only within solving its individual issues. This causes fragmentation and incompleteness of information about the conditions of a shot in judicial ballistics, hinders its development, reduces the possibility of a forensic ballistic examination in providing disclosure and investigation of crimes. In order to solve the problem, the authors examined the nature of scientific knowledge about the conditions of a shot in judicial ballistics, assessed their place in the system of judicial ballistics, identified areas of scientific knowledge that determine their content. It is established that scientific knowledge about the conditions of the shot is derived from judicial ballistics and is of a theoretical and applied nature, reflecting the principle of building knowledge, their focus on taking into account the influence of these conditions in displaying the properties and attributes of weapons, cartridges and traces of their action in solving expert problems. The process of generating information about the conditions of the shot, in addition to the scientific and methodological apparatus of forensic ballistics, determines the integration of the scientific knowledge of forensics, forensics, military equipment and forensic medicine. An element of the development of judicial ballistics is the structural isolation in it of a section containing a system of scientific knowledge about the conditions of the shot. This will allow focusing on the theoretical, methodological and organizational side of the problem, create conditions for increasing the scientific and methodological support of forensic ballistic expert studies.

In the work, a review of scientific articles on the behavior of tissues and organs of the human body under local mechanical effects on it, as well as a description of the physico-mechanical properties of biological materials. The selection of mechanical behavior for each biological material as part of a mathematical model of the human torso was carried out, its finite element model was created, validation experiments were modeled using data presented in the literature. An original calculation model of a human torso with a tuned interaction of organs with each other was developed. Contact interaction parameters are determined. The developed computational model of a human torso was verified based on data from open sources for an experiment with mechanical action by a cylindrical impactor. An algorithm for processing pressure and acceleration graphs has been implemented in order to obtain tolerance curves. A specialized modular program has been created for the automated processing of calculation results and the output of the main results. 42 numerical tests were carried out simulating the entry of a steel ball into each of 21 zones for power engineers of 40 and 80 J. According to the results of the tests for each organ, pressure and acceleration tolerance curves were obtained, animations of the behavior of organs under shock were created, visualization of the pressure field propagation in organs was obtained torso.

Few firearms have attracted as much attention, curiosity, and mythical attributes as the blunderbuss. Indeed, it often seems that fiction has overwhelmed the facts. To add to the mystery, the liter...

Modern system accuracy studies require high fidelity representations of environmental phenomena in order to accurately predict the down range performance of a gun system. One component of the atmosphere that has not been studied in great detail within the ballistic domain is turbulence. The current portrayal of wind leveraged by system analysis efforts ignores this element of atmospheric motion completely and thus its effects on down range dispersion have not been quantified. As a first step in addressing this deficiency, this study develops a methodology for generating synthetic turbulent wind signals along the flight path of a projectile. This goal is accomplished by integrating the work of several authors, developing techniques to fill knowledge gaps, and tailoring the solution to the direct fire domain. The significant contributions of the presented effort include mean flow direction agnostic spectral functions, provisions to account for the non-homogeneity of turbulence parameters along a trajectory, and a higher fidelity signal generation method than was used in previous work. The new information is applied to a sample engagement scenario in order to demonstrate the realization of the given techniques within the small caliber direct fire domain.

The identification of firearms from forensic ballistics specimens is an exacting and intensive activity performed by specialists with extensive experience. The introduction of imaging technology to assist the identification process of firearms has enhanced the ability of forensic ballisticians to conduct analyses of these specimens for identification. The positive identification of ballistics specimens from imaging systems are important applications of technology in criminal investigation [1] [2] [3] [4]. While the image capture methodology for persons and forensic ballistics specimens is similar, the process of identification for each is dependent upon the level of certainty required for the identification. The forensic identification of ballistics specimens relies on the detection, recognition and ultimate matching of markings on the surfaces of cartridges and projectiles made by the firearms [5]. Traditional methods for the comparison of these marks are based on incident light microscopy. The image formed from the oblique illumination of the mark gives a representation of the surface of the specimen in the region of the mark [6]. This representation is critically dependent on the material of the surface on which the marks have been made, and the geometry and intensity of the illumination system. The assessment by the ballistician of the similarity between comparable marks on respective ballistics specimens from crime scenes and test firings will be based on the expertise and experience of the technologist. Thus the traditional method of matching markings has inherent difficulties, and entails an element of subjectivity [7]. The need for firearm identification systems by police services continues to increase with greater accessibility to weapons in the international contexts. The characteristic markings on the cartridge and projectile of a bullet fired from a gun can be recognized as a fingerprint for identification of the firearm [8]. Forensic ballistics imaging has the capacity to produce highresolution digital images of cartridge cases and projectiles for matching to a library of ballistics images [9]. However, the reliance upon imaging technologies makes identification of ballistics specimens both a demanding and exacting task, where the control of the error of

Booming technological advances and turbulent military reforms have promoted the continuous advancement of weapons and equipment. High-power microwave (HPM) weapons have changed the damage modes of traditional guns, missiles and other kinetic energy weapons, as well as having the huge advantage of "changing the rules of the game." The study of exterior ballistics of high-power microwave weapons has theoretical support for the design and development of weapons and the verification of performance indicators, and is also an important basis in the firing application of high-power microwave weapons. By studying the coupling mechanism between HPM weapons and targets, an exterior ballistics description of HPM weapons is given According to the description of exterior ballistics, the differences between HPM and traditional weapons in definitions, accuracies, space trajectories, space descriptions and "end points" are summarized and the exterior ballistics space transmission is established. This study reveals the nine major transmission laws of the exterior ballistics of HPM weapons. The constructed model and related theories of the transmission laws for exterior ballistics lay a theoretical foundation for the in-depth study of key technologies of HPM weapons, such as fire control and damage assessment.

In order to better simulate the vertical ejection process of a certain type of surface-to-air missile, this article establishes a certain type of surface-to-air missile ejection device high-pressure indoor ballistic equation, low-pressure indoor ballistic equation, missile motion equation and pressure relief hole exhaust equation, and use MATLAB software to program. The pressure curves of the high and low pressure chambers with time, the gunpowder combustion curve and the missile movement curve are obtained. Comparing the data simulation results with the research results of other scholars, the results show that the algorithm can better reflect the change trend of each key parameter in the missile ejection process, and the obtained data can be used as the experimental basis for missile launch dynamics simulation.

Ballistic traumas are defined by a projectile entering the body. Such projectiles include bullets, birdshot, and metal fragments from the covering or the contents of an explosive device. They frequently cause severe wounds characterized by a range of clinical pictures and a large spectrum of concomitant wounds. The major aims of imaging are to define the path of the projectile or projectiles, to evaluate which tissues have been injured, to estimate the severity of injury, and to determine what additional studies are needed. A routine radiograph is performed in patients with gunshot wounds. The diagnostic approach has been changed by the use of multidetector row computed tomography (MDCT) due to its technical developments particularly faster data acquisition and advanced image reconstructions. In the evaluation of patients with gunshot injuries, MDCT is considered the method of choice to identify hemorrhage, bullet, bone fragments, air, hemothorax, nerve lesions, musculoskeletal lesions, and vessel injuries. Moreover, MDCT technology and multiplanar reformation postprocessing allow meticulous trajectory analysis that potentially benefits the clinical outcomes of patients aiding time-saving triage and correct image-based diagnosis of organ and vessel damage. Familiarity of ballistics and forensic sciences will therefore help the radiologist in assessment and localization of the damage caused by projectiles.

The development of the interior ballistics general model of gun propellant systems by taking into account the specificity of the recoilless propellant system is presented in this paper. The presented expanded physical and mathematical model makes possible the simulation of classical and nonclassical gun systems: two-chamber, mortar, and the considered recoilless one. To solve the system of equations associated with the mathematical model, a computer programme was developed. An analysis was made for two configurations of a recoilless system, differing in the way of arrangement of a propellant charge, i.e., with the propellant charge moving together with a projectile and with the propellant charge burning in a cartridge chamber. The obtained calculation results showed that the system, in which the propellant charge moves together with a projectile, has the maximum pressure and the muzzle velocity higher in comparison with the system with the propellant charge burning in a cartridge chamber. Influence of a way of placement of the propellant charge is the stronger, the higher is the ratio of its mass to the projectile mass. The results of the accomplished calculations, especially the pressure inside the barrel as well as motion parameters of the projectile make the grounds for projecting and construction optimization of the recoilless gun systems.

Computational fluid dynamics is becoming a key tool for reducing the hybrid rocket operation uncertainties and development cost, but numerous challenges, due to the complexity of modeling the solid fuel consumption mechanism and the interaction with the reacting flowfield, have still to be addressed. These latter features are further complicated with paraffins for the melted-fuel entrainment phenomenon. This paper presents a computational thermo-fluid-dynamic model of the internal ballistics of hybrid rockets burning gaseous oxygen and paraffin-based fuel. With the purpose of predicting the local fuel regression rate, the model is coupled with an improved gas/fuel-surface interface treatment based on local mass, energy and mean mixture fraction balances, combined to an additional analytical equation for the calculation of the entrainment fraction of the fuel consumption rate. Parametric analyses are carried out to assess the effect of fuel properties on the regression rate. Several experimental test cases, obtained from static firing of a laboratory-scale rocket, are simulated. Calculated regression rates show an error with respect to the measured data around 10% in the worst case. Chamber pressure is predicted with lower accuracy, with errors less than 20%; the main factor of deviation is shown to be the estimation of the combustion efficiency.

Projectile injuries to the face deserve particular attention to evaluate for involvement of critical structures and functional elements and treat the devastating effects on facial aesthetics. Ballistic trauma to the maxillofacial region often has significant soft tissue and bony defects, creating a greater challenge to the reconstructive surgeon. The main goals of treatment of projectile injuries to the face are decreasing the amount of contaminants and nonviable tissue at the site, ensuring functionality, and restoring aesthetic appearance. There exists a lack of robust research on the subject. Soft tissue injuries from high-velocity projectiles have changed the perspective on treating acute injuries to the face and neck. Injuries encountered during both Operation Iraqi Freedom and Operation Enduring Freedom give the author pause to reflect upon a different wounding pattern than that encountered in stateside trauma centers. Given the dissemination of high-velocity weaponry by enemy combatants such as the improvised explosive device, mortar round, and high-velocity rifles, a higher incidence of facial wounds has been reported. The mechanism of injury and a stepwise approach for surgical repair are discussed incorporating advanced trauma life support principles and a reconstructive ladder of repair.

Hybrid rockets are considered a promising future propulsion alternative for specific applications to solid or liquid rockets. In order to raise their technology readiness level, it is important to perform predictive numerical simulations of their internal ballistics. The objective of this work is to describe and validate a numerical approach based on Reynolds-averaged Navier–Stokes simulations with sub-models for fluid–surface interaction, radiation, chemistry, and turbulence. Particular attention is given to scale effects by considering two different paraffin–oxygen hybrid rocket engines and a simplified grain evolution approach from the initial to the final port diameter. Moreover, a mild sensitivity of the computed regression rate to paraffin’s melting temperature, surface radiation emissivity, and Schmidt numbers is observed. Results highlight the increasing importance of radiation effects at larger scales and pressures. A numerical rebuilding of regression rate and pressure is obtained with simulations at the time-space-averaged port diameter, producing a reasonable agreement with the available experimental data, but a noticeable improvement is obtained by considering the grain evolution in time.

Terminal ballistics is my favourite subject. I started my career teaching this as a young lecturer at the Royal Military College of Science at Shrivenham.

An atlatl or spearthrower is perhaps humanity’s oldest technology for accelerating projectiles. The dynamics prior to launch of the dart projectile have been much discussed in the literature. In this article we present a simple new model of launch dynamics and show that dart flex is not an important factor in determining launch speed, but it increases accuracy. The atlatl is a lever but only indirectly; the significant parameters for increasing launch speed are applied energy, and angular difference between force direction and dart direction. This study exhibits some instructive elements of Newtonian mechanics.

“RT-400” rocket aerial target system is described in the paper; research method of its simplified external ballistics characteristics is presented and the obtained results are discussed. This system was designed, tested, and produced by a research team of the Institute of Defence Technologies at Kaunas University of Technology and successfully implemented in practice. One of main aims of this paper was to develop external ballistics’ model of a rocket propelled aerial target which would enable obtaining various ballistic parameters of the investigated vehicle such as its acceleration, velocity, flight angle, flight range and trajectory using as input the internal ballistics data obtained at earlier experimental research of the “RV-12K” rocket motor in a static horizontal test stand for thrust measurements and determination of other internal ballistics’ characteristics such as combustion chamber temperature and pressure. During the experimental research process of the vehicle, under test site conditions, the main aim was to compare accuracy of the obtained external ballistics simulation data with the data obtained during experimental approaches using additional measurement techniques such as radar tracking and crash site and launch site GPS coordinates marking.

The article is focused on the development of the underwater ballistic model of a supercavitating projectile fired from an underwater firearm. The supercavitating flows and their influences on the ballistic characteristics of the projectile are studied. The presented mathematical model is validated and experimentally verified for the supercavitating projectile of 5.7 mm in diameter fired from a smooth bore underwater rifle.

A 28-year-old male presented to the emergency department with an isolated ulnar shaft fracture secondary to a ballistic injury with a wooden pellet gun. This injury is also known as a “nightstick fracture,” which is a common eponym in orthopedic surgery used to describe a fracture of the ulnar shaft. The eponym gained its title for the injury commonly seen when in a defensive position while being attacked with a wooden club. It is widely accepted that this infamous injury was popularized in the 1960s as a sequela of the many race-related riots across the United States. This case details how the nightstick fracture is still prevalent as a result of political protesting today, despite modern-day methods of non-lethal riot control.

The ballistics equations for spherical pellets in free flight are simplified through appropriate scaling of the pellet velocity and pellet distance. Two different drag coefficient curves are averaged to yield a single curve applicable to shot pellets and round balls. The resulting S-shaped drag coefficient curve is approximated by three straight-line segments. The scaled ballistics equations are then solved exactly and simple formulas are found for the velocity and flight time with respect to trajectory distance. The formulas are applicable to spherical shot pellets and round balls of any composition under any atmospheric conditions. The formulas are amenable to quick and easy computation and may also serve as an aid in understanding and comparing black-box ballistics calculators. For shotshell ballistics, an important assumption in the present investigation is that the pellets are moving as single, free spheres and not as a dense cloud or in a shot column, in particular, the pellets are not interacting during flight. Therefore, the formulas are most appropriate for single round balls, for large shot sizes, and for pellets of small shot size fired from open chokes. The formulas are clear and accessible, and can be implemented by military or law enforcement personnel as well as hunters and shooters. This work differs from previous investigations in that accurate ballistics formulas are derived for spherical projectiles of shotguns and muzzleloaders using realistic drag coefficients.

Wounds due to gunshot and explosions, while usually observed during battlefield combat, are no longer an exceptional occurrence in civilian practice in France. The principles of wound ballistics are based on the interaction between the projectile and the human body as well as the transfer of energy from the projectile to tissues. The treatment of ballistic wounds relies on several principles: extremity wound debridement and absence of initial closure, complementary medical treatment, routine immobilization, revision surgery and secondary closure. Victims of explosions usually present with a complex clinical picture since injuries are directly or indirectly related to the shock wave (blast) originating from the explosion. These injuries depend on the type of explosive device, the environment and the situation of the victim at the time of the explosion, and are classed as primary, secondary, tertiary or quaternary. Secondary injuries due to flying debris and bomb fragments are generally the predominant presenting symptoms while isolated primary injuries (blast) are rare. The resulting complexity of the clinical picture explains why triage of these victims is particularly difficult. Certain myths, such as inevitable necrosis of the soft tissues that are displaced by the formation of the temporary cavitation by the projectile, or sterilization of the wounds by heat generated by the projectile should be forgotten. Ballistic-protective body armor and helmets are not infallible, even when they are not perforated, and can even be at the origin of injuries, either due to missile impact, or to the blast.

This study employs a structural contingency theory framework to assess the influence of the formal organizational structure of crime laboratories and their environments, on the productivity of labs’ ballistics imaging systems. We contribute to the nascent evolution of organizational focus in forensics while exploring different ways in which overall lab performance can be conceptualized. We analyze data provided by the Bureau of Alcohol, Tobacco, Firearms and Explosives’ (ATF) National Integrated Ballistics Information Network (NIBIN), and data from the Bureau of Justice Statistics, Census of Publicly Funded Forensic Crime Laboratories, 2009. Three Negative Binomial models regressed the organizational and environmental variables on the productivity of crime labs, operationalized as their ability to produce bullet, brass, and total hits. Results indicate that in addition to the number of bullet and brass inputs, local labs are more productive in identifying ballistics imaging hits. Additionally, lar...

Compared to computed tomography (CT), magnetic resonance imaging (MRI) provides superior visualization of the soft tissue. Recently, the first 7 Tesla (7 T) MRI scanner was approved for clinical use, which will facilitate access to these ultra-high-field MRI scanners for noninvasive examinations and scientific studies on decedents. 7 T MRI has the potential to provide a higher signal-to-noise ratio (SNR), a characteristic that can be directly exploited to improve image quality and invest in attempts to increase resolution. Therefore, evaluating the diagnostic potential of 7 T MRI for forensic purposes, such as assessments of fatal gunshot wounds, was deemed essential. In this article, we present radiologic findings obtained for craniocerebral gunshot wounds in three decedents. The decedents were submitted to MRI examinations using a 7 T MRI scanner that has been approved for clinical use and a clinical 3 T MRI scanner for comparison. We focused on detecting tiny injuries beyond the wound tract caused by temporary cavitation, such as microbleeds. Additionally, 7 T T2-weighted MRI highlighted a dark (hypo intense) zone beyond the permanent wound tract, which was attributed to increased amounts of paramagnetic blood components in damaged tissue. Microbleeds were also detected adjacent to the wound tract in the white matter on 7 T MRI. Based on the findings of radiologic assessments, the advantages and disadvantages of postmortem 7 T MRI compared to 3 T MRI are discussed with regard to investigations of craniocerebral gunshot wounds as well as the potential role of 7 T MRI in the future of forensic science.

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.

The Directorate of Forensic Science Laboratories, Mumbai-India, has been receiving and examining homemade/desi-katta/improvised firearms for a long time. In all these cases, our work is always focu...

Exterior ballistics performance evaluation plays a critical role in the design and development of the electromagnetic railgun system. The ballistics performance evaluation can be regarded as a multicriteria decision-making problem, for the reason that various characteristics, also termed criteria, have effects on the overall performance. A sophisticated simulation model, including six-DOF mechanics, railgun configuration, environment, and aerodynamics models are established to compute the exterior ballistics profile. Then a comprehensive framework based on cloud model and analytic hierarchy process method are proposed to evaluate ballistics performance. Eight criteria including ballistics velocity, energy efficiency, flight time, flight range, overload, attack angle, and sideslip angle stability are selected to determine exterior ballistics performance. The proposed approach yields the certainty degree of each criterion and integrates multicriteria into the whole performance. Two scenarios including 32-MJ launch energy and 200-km strike range are taken to generate alternatives for assessing ballistics performance, which demonstrate the proposed approach is feasible. Results show that in the same launch energy 32 MJ, the performance levels of 12- and 16-kg projectiles are I (excellent) and III (medium), respectively. Besides, gaining the projectile’s mass can improve performance in the same strike range 200 km.

The incidence of civilian gunshot injuries is on the rise worldwide.Unfortunately, there is a lack of high-level evidence guiding management. The treatment of orthopaedic injuries from gunshots is complex and requires consideration of multiple aspects, including energy transfer to the tissue, severity of the wound, possible contamination, presence of fractures and associated injuries. With this narrative review we aim to discuss some of the relevant ballistics, current concepts, and controversies in the general management of civilian gunshot-related orthopaedic injuries based on the available evidence and personal experience. Important points which will be highlighted are the initial management in the emergency room, the assessment and management of soft tissue injuries, associated injuries, use of antibiotics, indication and techniques for fracture fixation, and gunshot injuries to joints.

The wound ballistics literature contains several misconceptions about the physical effects of penetrating projectiles in tissue and tissue simulants. These can adversely affect the proper management of gunshot injuries, particularly in view of the ongoing threat of terrorist and criminal acts using assault rifles against civilians. The understanding of the wounding effects by military rifle bullets can be founded on the concept of energy transfer to the wound as applied to high-energy missile trauma. A substantial component of high-energy transfer in assault rifle injuries is manifested by the dynamic phenomenon of temporary cavitation, which is extensively reviewed with respect to its impact on the wound production and the associated controversy surrounding its consequences in soft tissue wounds. Part of this controversy emanates from misinterpretation of experimental data regarding the magnitude of the temporary cavity induced by high-velocity projectiles and the different conceptions of the tissue response to cavitation. The interaction between the projectile and tissue can lead to tumbling and possibly to deformation and fragmentation of the bullet, all of which strongly influence the energy transfer characteristics affecting both the temporary cavitation and the size of the permanent wound channel. Awareness of these effects can enhance perception of clinical and radiological findings suggestive of the wounding mechanism by various projectiles. LEVEL OF EVIDENCE: Review/therapeutic, level V.

Описывается программное обеспечение поддержки расчета внешней баллистики для оружия калибра 5,45 мм с учетом внешних факторов тактического тренажера оптико-электронного для стрелкового оружия «Ингибитор», разработанного в Институте механики УдмФИЦ УрО РАН и на кафедре «Вычислительная техника» ИжГТУ имени М. Т. Калашникова совместно с АО «Концерн «Калашников». Приводится тактико-техническое задание для баллистического расчета траектории до 2 км дальности имитаторов оружия с лазерным излучателем точки прицеливания с учетом внешних факторов: положения прицельной планки всех видов прицелов, температуры и давления воздуха, которые оказывают существенное влияние на сопротивление воздуха. Реализованная дифференциальная математическая модель внешней баллистики, опираясь на угол прицеливания имитатора оружия, начальную скорость и баллистический коэффициент боеприпаса в реальном времени, строит баллистическую траекторию с поправками на температуру и давление воздуха. Приводятся результаты испытаний программного обеспечения на погрешность расчета координат баллистической траектории. Сделан вывод о перспективности дальнейших исследований и разработке электронных стрелковых тренажеров благодаря совершенствованию и удешевлению элементной базы и развитию программных библиотек с целью повышения точности имитации внешней баллистики тренажеров с учетом многих внешних факторов, расширения функциональных возможностей и снижения себестоимости и, значит, повышения конкурентоспособности.

According to the characteristics of small caliber grenade, this paper establishes its internal and external ballistic model, and studies the characteristics and basic rules of internal and external ballistic of grenade. The key factors affecting the accuracy of the distance model are analyzed, and the techniques and methods for determining the parameters of the distance model are studied. The measuring system and wireless setting system for the precise control of small caliber grenade blast point are designed. The theoretical method of controlling the blast point of projectile by DSP chip and improving the accuracy of distance determination is described. Finally, a wireless setting system is constructed based on related theories and sensors.

The computational fluid dynamics of hybrid rocket internal ballistics is becoming a key tool for reducing the engine operation uncertainties and development cost as well as for improving experimental data analysis. Nevertheless, its application still presents numerous challenges for the complexity of modeling the phenomena involved in the fuel consumption mechanism and its coupling with the chemically reacting flowfield. This paper presents a review of the computational thermo-fluid-dynamic models developed for the internal ballistics of hybrid rockets burning gaseous oxygen with classical polymeric or paraffin-based fuels, with a special focus on the interaction between the fluid and the solid fuel surface. With the purpose of predicting the local fuel regression rate, which is the main parameter needed for the hybrid rocket design, the model is coupled with an improved gas/surface interface treatment based on local mass, energy and mean mixture-fraction balances, combined to either a pyrolysis-rate equation in the case of classical polymers, or to an additional equation for the liquid paraffin entrainment fraction of the total fuel consumption rate. A number of experimental test cases obtained from the static firing of two different laboratory-scale rockets are simulated to determine the models’ capabilities, showing very good agreement between the calculated and measured fuel regression rates with both standard pyrolyzing and liquefying fuels. The prediction of the chamber pressure measured with paraffin fuel resulted in it being more cumbersome for the single-phase flow assumption. The advantages and limitations of the models are discussed.

The tremendous improvement made over the last ten years in radiotherapy has been achieved mainly by developing particle acceleration techniques. Three-dimensional conformal radiation therapy [3D-CRT] is crucially applied for decreasing the shape of advanced rectal tumors yet has several side consequences. Our investigation examined the dose distribution in planning target volumes (PTV), the protection of healthy organs at risk (OAR), and the quality of therapy for the two strategies based on the three fields and four fields ballistic used in treating rectal cancers. Using the Varian Linear Accelerator system (Varian Medical Systems, Inc., Palo Alto, CA, USA) integrated with an Eclipse MLC 2100 planning system including Pencil Beam Convolution PBC dose calculation algorithm. Two different treatments of rectal cancer based on the two approaches are performed. A dosimetric comparison of the parameters is made to evaluate the feasibility of each ballistic. These parameters, including the target volume coverage indicators, included average dose, conformity index (CI), and homogeneity index (HI) of planning tumor volume; OAR included the bladder and bilateral proximal femurs. The results achieved in this dosimetric comparative study advocate for the clinical application of three fields ballistic in all specialties already compared, except for the planning target volume PTV dose distribution. The study has shown that the three-field technique (an anterior and two opposing lateral fields with the portals orientation 0°, 90°, 270°) and applied energy photons of 18 MV and 6 MV provides the best bladder protection. According to the dose distribution in the target (PTV), all evaluated plans have not indicated any significant differences. The risk of morbidity in the femoral heads for all the applied methods, in a dose up to 56.396 Gy, was not a therapeutic problem. However, the three-field approach with beams orientation 0°, 120°, 240°gave the best sparing effect for femoral heads.

A mathematical-physical model of the hypersonic anti-tank kinetic subcalibre projectile for 120 mm munition was built. Computer simulations of the projectile flight were performed for any angle of shooting, from 0° to 90°. Trajectories of projectile flights were determined considering all angles of shooting. Theoretical calculations were verified by experimental measurement of the projectile velocity in time while shooting on a test range. Some conclusions with regard to safety during hypersonic projectile shooting on the test range were formulated.